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Linux/net/sctp/socket.c

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  1 /* SCTP kernel implementation
  2  * (C) Copyright IBM Corp. 2001, 2004
  3  * Copyright (c) 1999-2000 Cisco, Inc.
  4  * Copyright (c) 1999-2001 Motorola, Inc.
  5  * Copyright (c) 2001-2003 Intel Corp.
  6  * Copyright (c) 2001-2002 Nokia, Inc.
  7  * Copyright (c) 2001 La Monte H.P. Yarroll
  8  *
  9  * This file is part of the SCTP kernel implementation
 10  *
 11  * These functions interface with the sockets layer to implement the
 12  * SCTP Extensions for the Sockets API.
 13  *
 14  * Note that the descriptions from the specification are USER level
 15  * functions--this file is the functions which populate the struct proto
 16  * for SCTP which is the BOTTOM of the sockets interface.
 17  *
 18  * This SCTP implementation is free software;
 19  * you can redistribute it and/or modify it under the terms of
 20  * the GNU General Public License as published by
 21  * the Free Software Foundation; either version 2, or (at your option)
 22  * any later version.
 23  *
 24  * This SCTP implementation is distributed in the hope that it
 25  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 26  *                 ************************
 27  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 28  * See the GNU General Public License for more details.
 29  *
 30  * You should have received a copy of the GNU General Public License
 31  * along with GNU CC; see the file COPYING.  If not, see
 32  * <http://www.gnu.org/licenses/>.
 33  *
 34  * Please send any bug reports or fixes you make to the
 35  * email address(es):
 36  *    lksctp developers <linux-sctp@vger.kernel.org>
 37  *
 38  * Written or modified by:
 39  *    La Monte H.P. Yarroll <piggy@acm.org>
 40  *    Narasimha Budihal     <narsi@refcode.org>
 41  *    Karl Knutson          <karl@athena.chicago.il.us>
 42  *    Jon Grimm             <jgrimm@us.ibm.com>
 43  *    Xingang Guo           <xingang.guo@intel.com>
 44  *    Daisy Chang           <daisyc@us.ibm.com>
 45  *    Sridhar Samudrala     <samudrala@us.ibm.com>
 46  *    Inaky Perez-Gonzalez  <inaky.gonzalez@intel.com>
 47  *    Ardelle Fan           <ardelle.fan@intel.com>
 48  *    Ryan Layer            <rmlayer@us.ibm.com>
 49  *    Anup Pemmaiah         <pemmaiah@cc.usu.edu>
 50  *    Kevin Gao             <kevin.gao@intel.com>
 51  */
 52 
 53 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 54 
 55 #include <linux/types.h>
 56 #include <linux/kernel.h>
 57 #include <linux/wait.h>
 58 #include <linux/time.h>
 59 #include <linux/ip.h>
 60 #include <linux/capability.h>
 61 #include <linux/fcntl.h>
 62 #include <linux/poll.h>
 63 #include <linux/init.h>
 64 #include <linux/crypto.h>
 65 #include <linux/slab.h>
 66 #include <linux/file.h>
 67 #include <linux/compat.h>
 68 
 69 #include <net/ip.h>
 70 #include <net/icmp.h>
 71 #include <net/route.h>
 72 #include <net/ipv6.h>
 73 #include <net/inet_common.h>
 74 #include <net/busy_poll.h>
 75 
 76 #include <linux/socket.h> /* for sa_family_t */
 77 #include <linux/export.h>
 78 #include <net/sock.h>
 79 #include <net/sctp/sctp.h>
 80 #include <net/sctp/sm.h>
 81 
 82 /* Forward declarations for internal helper functions. */
 83 static int sctp_writeable(struct sock *sk);
 84 static void sctp_wfree(struct sk_buff *skb);
 85 static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
 86                                 size_t msg_len);
 87 static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);
 88 static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
 89 static int sctp_wait_for_accept(struct sock *sk, long timeo);
 90 static void sctp_wait_for_close(struct sock *sk, long timeo);
 91 static void sctp_destruct_sock(struct sock *sk);
 92 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
 93                                         union sctp_addr *addr, int len);
 94 static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
 95 static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);
 96 static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);
 97 static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);
 98 static int sctp_send_asconf(struct sctp_association *asoc,
 99                             struct sctp_chunk *chunk);
100 static int sctp_do_bind(struct sock *, union sctp_addr *, int);
101 static int sctp_autobind(struct sock *sk);
102 static void sctp_sock_migrate(struct sock *, struct sock *,
103                               struct sctp_association *, sctp_socket_type_t);
104 
105 static int sctp_memory_pressure;
106 static atomic_long_t sctp_memory_allocated;
107 struct percpu_counter sctp_sockets_allocated;
108 
109 static void sctp_enter_memory_pressure(struct sock *sk)
110 {
111         sctp_memory_pressure = 1;
112 }
113 
114 
115 /* Get the sndbuf space available at the time on the association.  */
116 static inline int sctp_wspace(struct sctp_association *asoc)
117 {
118         int amt;
119 
120         if (asoc->ep->sndbuf_policy)
121                 amt = asoc->sndbuf_used;
122         else
123                 amt = sk_wmem_alloc_get(asoc->base.sk);
124 
125         if (amt >= asoc->base.sk->sk_sndbuf) {
126                 if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
127                         amt = 0;
128                 else {
129                         amt = sk_stream_wspace(asoc->base.sk);
130                         if (amt < 0)
131                                 amt = 0;
132                 }
133         } else {
134                 amt = asoc->base.sk->sk_sndbuf - amt;
135         }
136         return amt;
137 }
138 
139 /* Increment the used sndbuf space count of the corresponding association by
140  * the size of the outgoing data chunk.
141  * Also, set the skb destructor for sndbuf accounting later.
142  *
143  * Since it is always 1-1 between chunk and skb, and also a new skb is always
144  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
145  * destructor in the data chunk skb for the purpose of the sndbuf space
146  * tracking.
147  */
148 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
149 {
150         struct sctp_association *asoc = chunk->asoc;
151         struct sock *sk = asoc->base.sk;
152 
153         /* The sndbuf space is tracked per association.  */
154         sctp_association_hold(asoc);
155 
156         skb_set_owner_w(chunk->skb, sk);
157 
158         chunk->skb->destructor = sctp_wfree;
159         /* Save the chunk pointer in skb for sctp_wfree to use later.  */
160         skb_shinfo(chunk->skb)->destructor_arg = chunk;
161 
162         asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
163                                 sizeof(struct sk_buff) +
164                                 sizeof(struct sctp_chunk);
165 
166         atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
167         sk->sk_wmem_queued += chunk->skb->truesize;
168         sk_mem_charge(sk, chunk->skb->truesize);
169 }
170 
171 /* Verify that this is a valid address. */
172 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
173                                    int len)
174 {
175         struct sctp_af *af;
176 
177         /* Verify basic sockaddr. */
178         af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
179         if (!af)
180                 return -EINVAL;
181 
182         /* Is this a valid SCTP address?  */
183         if (!af->addr_valid(addr, sctp_sk(sk), NULL))
184                 return -EINVAL;
185 
186         if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
187                 return -EINVAL;
188 
189         return 0;
190 }
191 
192 /* Look up the association by its id.  If this is not a UDP-style
193  * socket, the ID field is always ignored.
194  */
195 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
196 {
197         struct sctp_association *asoc = NULL;
198 
199         /* If this is not a UDP-style socket, assoc id should be ignored. */
200         if (!sctp_style(sk, UDP)) {
201                 /* Return NULL if the socket state is not ESTABLISHED. It
202                  * could be a TCP-style listening socket or a socket which
203                  * hasn't yet called connect() to establish an association.
204                  */
205                 if (!sctp_sstate(sk, ESTABLISHED))
206                         return NULL;
207 
208                 /* Get the first and the only association from the list. */
209                 if (!list_empty(&sctp_sk(sk)->ep->asocs))
210                         asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
211                                           struct sctp_association, asocs);
212                 return asoc;
213         }
214 
215         /* Otherwise this is a UDP-style socket. */
216         if (!id || (id == (sctp_assoc_t)-1))
217                 return NULL;
218 
219         spin_lock_bh(&sctp_assocs_id_lock);
220         asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
221         spin_unlock_bh(&sctp_assocs_id_lock);
222 
223         if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
224                 return NULL;
225 
226         return asoc;
227 }
228 
229 /* Look up the transport from an address and an assoc id. If both address and
230  * id are specified, the associations matching the address and the id should be
231  * the same.
232  */
233 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
234                                               struct sockaddr_storage *addr,
235                                               sctp_assoc_t id)
236 {
237         struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
238         struct sctp_transport *transport;
239         union sctp_addr *laddr = (union sctp_addr *)addr;
240 
241         addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
242                                                laddr,
243                                                &transport);
244 
245         if (!addr_asoc)
246                 return NULL;
247 
248         id_asoc = sctp_id2assoc(sk, id);
249         if (id_asoc && (id_asoc != addr_asoc))
250                 return NULL;
251 
252         sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
253                                                 (union sctp_addr *)addr);
254 
255         return transport;
256 }
257 
258 /* API 3.1.2 bind() - UDP Style Syntax
259  * The syntax of bind() is,
260  *
261  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
262  *
263  *   sd      - the socket descriptor returned by socket().
264  *   addr    - the address structure (struct sockaddr_in or struct
265  *             sockaddr_in6 [RFC 2553]),
266  *   addr_len - the size of the address structure.
267  */
268 static int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
269 {
270         int retval = 0;
271 
272         lock_sock(sk);
273 
274         pr_debug("%s: sk:%p, addr:%p, addr_len:%d\n", __func__, sk,
275                  addr, addr_len);
276 
277         /* Disallow binding twice. */
278         if (!sctp_sk(sk)->ep->base.bind_addr.port)
279                 retval = sctp_do_bind(sk, (union sctp_addr *)addr,
280                                       addr_len);
281         else
282                 retval = -EINVAL;
283 
284         release_sock(sk);
285 
286         return retval;
287 }
288 
289 static long sctp_get_port_local(struct sock *, union sctp_addr *);
290 
291 /* Verify this is a valid sockaddr. */
292 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
293                                         union sctp_addr *addr, int len)
294 {
295         struct sctp_af *af;
296 
297         /* Check minimum size.  */
298         if (len < sizeof (struct sockaddr))
299                 return NULL;
300 
301         /* V4 mapped address are really of AF_INET family */
302         if (addr->sa.sa_family == AF_INET6 &&
303             ipv6_addr_v4mapped(&addr->v6.sin6_addr)) {
304                 if (!opt->pf->af_supported(AF_INET, opt))
305                         return NULL;
306         } else {
307                 /* Does this PF support this AF? */
308                 if (!opt->pf->af_supported(addr->sa.sa_family, opt))
309                         return NULL;
310         }
311 
312         /* If we get this far, af is valid. */
313         af = sctp_get_af_specific(addr->sa.sa_family);
314 
315         if (len < af->sockaddr_len)
316                 return NULL;
317 
318         return af;
319 }
320 
321 /* Bind a local address either to an endpoint or to an association.  */
322 static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
323 {
324         struct net *net = sock_net(sk);
325         struct sctp_sock *sp = sctp_sk(sk);
326         struct sctp_endpoint *ep = sp->ep;
327         struct sctp_bind_addr *bp = &ep->base.bind_addr;
328         struct sctp_af *af;
329         unsigned short snum;
330         int ret = 0;
331 
332         /* Common sockaddr verification. */
333         af = sctp_sockaddr_af(sp, addr, len);
334         if (!af) {
335                 pr_debug("%s: sk:%p, newaddr:%p, len:%d EINVAL\n",
336                          __func__, sk, addr, len);
337                 return -EINVAL;
338         }
339 
340         snum = ntohs(addr->v4.sin_port);
341 
342         pr_debug("%s: sk:%p, new addr:%pISc, port:%d, new port:%d, len:%d\n",
343                  __func__, sk, &addr->sa, bp->port, snum, len);
344 
345         /* PF specific bind() address verification. */
346         if (!sp->pf->bind_verify(sp, addr))
347                 return -EADDRNOTAVAIL;
348 
349         /* We must either be unbound, or bind to the same port.
350          * It's OK to allow 0 ports if we are already bound.
351          * We'll just inhert an already bound port in this case
352          */
353         if (bp->port) {
354                 if (!snum)
355                         snum = bp->port;
356                 else if (snum != bp->port) {
357                         pr_debug("%s: new port %d doesn't match existing port "
358                                  "%d\n", __func__, snum, bp->port);
359                         return -EINVAL;
360                 }
361         }
362 
363         if (snum && snum < PROT_SOCK &&
364             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
365                 return -EACCES;
366 
367         /* See if the address matches any of the addresses we may have
368          * already bound before checking against other endpoints.
369          */
370         if (sctp_bind_addr_match(bp, addr, sp))
371                 return -EINVAL;
372 
373         /* Make sure we are allowed to bind here.
374          * The function sctp_get_port_local() does duplicate address
375          * detection.
376          */
377         addr->v4.sin_port = htons(snum);
378         if ((ret = sctp_get_port_local(sk, addr))) {
379                 return -EADDRINUSE;
380         }
381 
382         /* Refresh ephemeral port.  */
383         if (!bp->port)
384                 bp->port = inet_sk(sk)->inet_num;
385 
386         /* Add the address to the bind address list.
387          * Use GFP_ATOMIC since BHs will be disabled.
388          */
389         ret = sctp_add_bind_addr(bp, addr, SCTP_ADDR_SRC, GFP_ATOMIC);
390 
391         /* Copy back into socket for getsockname() use. */
392         if (!ret) {
393                 inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num);
394                 sp->pf->to_sk_saddr(addr, sk);
395         }
396 
397         return ret;
398 }
399 
400  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
401  *
402  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
403  * at any one time.  If a sender, after sending an ASCONF chunk, decides
404  * it needs to transfer another ASCONF Chunk, it MUST wait until the
405  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
406  * subsequent ASCONF. Note this restriction binds each side, so at any
407  * time two ASCONF may be in-transit on any given association (one sent
408  * from each endpoint).
409  */
410 static int sctp_send_asconf(struct sctp_association *asoc,
411                             struct sctp_chunk *chunk)
412 {
413         struct net      *net = sock_net(asoc->base.sk);
414         int             retval = 0;
415 
416         /* If there is an outstanding ASCONF chunk, queue it for later
417          * transmission.
418          */
419         if (asoc->addip_last_asconf) {
420                 list_add_tail(&chunk->list, &asoc->addip_chunk_list);
421                 goto out;
422         }
423 
424         /* Hold the chunk until an ASCONF_ACK is received. */
425         sctp_chunk_hold(chunk);
426         retval = sctp_primitive_ASCONF(net, asoc, chunk);
427         if (retval)
428                 sctp_chunk_free(chunk);
429         else
430                 asoc->addip_last_asconf = chunk;
431 
432 out:
433         return retval;
434 }
435 
436 /* Add a list of addresses as bind addresses to local endpoint or
437  * association.
438  *
439  * Basically run through each address specified in the addrs/addrcnt
440  * array/length pair, determine if it is IPv6 or IPv4 and call
441  * sctp_do_bind() on it.
442  *
443  * If any of them fails, then the operation will be reversed and the
444  * ones that were added will be removed.
445  *
446  * Only sctp_setsockopt_bindx() is supposed to call this function.
447  */
448 static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
449 {
450         int cnt;
451         int retval = 0;
452         void *addr_buf;
453         struct sockaddr *sa_addr;
454         struct sctp_af *af;
455 
456         pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n", __func__, sk,
457                  addrs, addrcnt);
458 
459         addr_buf = addrs;
460         for (cnt = 0; cnt < addrcnt; cnt++) {
461                 /* The list may contain either IPv4 or IPv6 address;
462                  * determine the address length for walking thru the list.
463                  */
464                 sa_addr = addr_buf;
465                 af = sctp_get_af_specific(sa_addr->sa_family);
466                 if (!af) {
467                         retval = -EINVAL;
468                         goto err_bindx_add;
469                 }
470 
471                 retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
472                                       af->sockaddr_len);
473 
474                 addr_buf += af->sockaddr_len;
475 
476 err_bindx_add:
477                 if (retval < 0) {
478                         /* Failed. Cleanup the ones that have been added */
479                         if (cnt > 0)
480                                 sctp_bindx_rem(sk, addrs, cnt);
481                         return retval;
482                 }
483         }
484 
485         return retval;
486 }
487 
488 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
489  * associations that are part of the endpoint indicating that a list of local
490  * addresses are added to the endpoint.
491  *
492  * If any of the addresses is already in the bind address list of the
493  * association, we do not send the chunk for that association.  But it will not
494  * affect other associations.
495  *
496  * Only sctp_setsockopt_bindx() is supposed to call this function.
497  */
498 static int sctp_send_asconf_add_ip(struct sock          *sk,
499                                    struct sockaddr      *addrs,
500                                    int                  addrcnt)
501 {
502         struct net *net = sock_net(sk);
503         struct sctp_sock                *sp;
504         struct sctp_endpoint            *ep;
505         struct sctp_association         *asoc;
506         struct sctp_bind_addr           *bp;
507         struct sctp_chunk               *chunk;
508         struct sctp_sockaddr_entry      *laddr;
509         union sctp_addr                 *addr;
510         union sctp_addr                 saveaddr;
511         void                            *addr_buf;
512         struct sctp_af                  *af;
513         struct list_head                *p;
514         int                             i;
515         int                             retval = 0;
516 
517         if (!net->sctp.addip_enable)
518                 return retval;
519 
520         sp = sctp_sk(sk);
521         ep = sp->ep;
522 
523         pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
524                  __func__, sk, addrs, addrcnt);
525 
526         list_for_each_entry(asoc, &ep->asocs, asocs) {
527                 if (!asoc->peer.asconf_capable)
528                         continue;
529 
530                 if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
531                         continue;
532 
533                 if (!sctp_state(asoc, ESTABLISHED))
534                         continue;
535 
536                 /* Check if any address in the packed array of addresses is
537                  * in the bind address list of the association. If so,
538                  * do not send the asconf chunk to its peer, but continue with
539                  * other associations.
540                  */
541                 addr_buf = addrs;
542                 for (i = 0; i < addrcnt; i++) {
543                         addr = addr_buf;
544                         af = sctp_get_af_specific(addr->v4.sin_family);
545                         if (!af) {
546                                 retval = -EINVAL;
547                                 goto out;
548                         }
549 
550                         if (sctp_assoc_lookup_laddr(asoc, addr))
551                                 break;
552 
553                         addr_buf += af->sockaddr_len;
554                 }
555                 if (i < addrcnt)
556                         continue;
557 
558                 /* Use the first valid address in bind addr list of
559                  * association as Address Parameter of ASCONF CHUNK.
560                  */
561                 bp = &asoc->base.bind_addr;
562                 p = bp->address_list.next;
563                 laddr = list_entry(p, struct sctp_sockaddr_entry, list);
564                 chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
565                                                    addrcnt, SCTP_PARAM_ADD_IP);
566                 if (!chunk) {
567                         retval = -ENOMEM;
568                         goto out;
569                 }
570 
571                 /* Add the new addresses to the bind address list with
572                  * use_as_src set to 0.
573                  */
574                 addr_buf = addrs;
575                 for (i = 0; i < addrcnt; i++) {
576                         addr = addr_buf;
577                         af = sctp_get_af_specific(addr->v4.sin_family);
578                         memcpy(&saveaddr, addr, af->sockaddr_len);
579                         retval = sctp_add_bind_addr(bp, &saveaddr,
580                                                     SCTP_ADDR_NEW, GFP_ATOMIC);
581                         addr_buf += af->sockaddr_len;
582                 }
583                 if (asoc->src_out_of_asoc_ok) {
584                         struct sctp_transport *trans;
585 
586                         list_for_each_entry(trans,
587                             &asoc->peer.transport_addr_list, transports) {
588                                 /* Clear the source and route cache */
589                                 dst_release(trans->dst);
590                                 trans->cwnd = min(4*asoc->pathmtu, max_t(__u32,
591                                     2*asoc->pathmtu, 4380));
592                                 trans->ssthresh = asoc->peer.i.a_rwnd;
593                                 trans->rto = asoc->rto_initial;
594                                 sctp_max_rto(asoc, trans);
595                                 trans->rtt = trans->srtt = trans->rttvar = 0;
596                                 sctp_transport_route(trans, NULL,
597                                     sctp_sk(asoc->base.sk));
598                         }
599                 }
600                 retval = sctp_send_asconf(asoc, chunk);
601         }
602 
603 out:
604         return retval;
605 }
606 
607 /* Remove a list of addresses from bind addresses list.  Do not remove the
608  * last address.
609  *
610  * Basically run through each address specified in the addrs/addrcnt
611  * array/length pair, determine if it is IPv6 or IPv4 and call
612  * sctp_del_bind() on it.
613  *
614  * If any of them fails, then the operation will be reversed and the
615  * ones that were removed will be added back.
616  *
617  * At least one address has to be left; if only one address is
618  * available, the operation will return -EBUSY.
619  *
620  * Only sctp_setsockopt_bindx() is supposed to call this function.
621  */
622 static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
623 {
624         struct sctp_sock *sp = sctp_sk(sk);
625         struct sctp_endpoint *ep = sp->ep;
626         int cnt;
627         struct sctp_bind_addr *bp = &ep->base.bind_addr;
628         int retval = 0;
629         void *addr_buf;
630         union sctp_addr *sa_addr;
631         struct sctp_af *af;
632 
633         pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
634                  __func__, sk, addrs, addrcnt);
635 
636         addr_buf = addrs;
637         for (cnt = 0; cnt < addrcnt; cnt++) {
638                 /* If the bind address list is empty or if there is only one
639                  * bind address, there is nothing more to be removed (we need
640                  * at least one address here).
641                  */
642                 if (list_empty(&bp->address_list) ||
643                     (sctp_list_single_entry(&bp->address_list))) {
644                         retval = -EBUSY;
645                         goto err_bindx_rem;
646                 }
647 
648                 sa_addr = addr_buf;
649                 af = sctp_get_af_specific(sa_addr->sa.sa_family);
650                 if (!af) {
651                         retval = -EINVAL;
652                         goto err_bindx_rem;
653                 }
654 
655                 if (!af->addr_valid(sa_addr, sp, NULL)) {
656                         retval = -EADDRNOTAVAIL;
657                         goto err_bindx_rem;
658                 }
659 
660                 if (sa_addr->v4.sin_port &&
661                     sa_addr->v4.sin_port != htons(bp->port)) {
662                         retval = -EINVAL;
663                         goto err_bindx_rem;
664                 }
665 
666                 if (!sa_addr->v4.sin_port)
667                         sa_addr->v4.sin_port = htons(bp->port);
668 
669                 /* FIXME - There is probably a need to check if sk->sk_saddr and
670                  * sk->sk_rcv_addr are currently set to one of the addresses to
671                  * be removed. This is something which needs to be looked into
672                  * when we are fixing the outstanding issues with multi-homing
673                  * socket routing and failover schemes. Refer to comments in
674                  * sctp_do_bind(). -daisy
675                  */
676                 retval = sctp_del_bind_addr(bp, sa_addr);
677 
678                 addr_buf += af->sockaddr_len;
679 err_bindx_rem:
680                 if (retval < 0) {
681                         /* Failed. Add the ones that has been removed back */
682                         if (cnt > 0)
683                                 sctp_bindx_add(sk, addrs, cnt);
684                         return retval;
685                 }
686         }
687 
688         return retval;
689 }
690 
691 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
692  * the associations that are part of the endpoint indicating that a list of
693  * local addresses are removed from the endpoint.
694  *
695  * If any of the addresses is already in the bind address list of the
696  * association, we do not send the chunk for that association.  But it will not
697  * affect other associations.
698  *
699  * Only sctp_setsockopt_bindx() is supposed to call this function.
700  */
701 static int sctp_send_asconf_del_ip(struct sock          *sk,
702                                    struct sockaddr      *addrs,
703                                    int                  addrcnt)
704 {
705         struct net *net = sock_net(sk);
706         struct sctp_sock        *sp;
707         struct sctp_endpoint    *ep;
708         struct sctp_association *asoc;
709         struct sctp_transport   *transport;
710         struct sctp_bind_addr   *bp;
711         struct sctp_chunk       *chunk;
712         union sctp_addr         *laddr;
713         void                    *addr_buf;
714         struct sctp_af          *af;
715         struct sctp_sockaddr_entry *saddr;
716         int                     i;
717         int                     retval = 0;
718         int                     stored = 0;
719 
720         chunk = NULL;
721         if (!net->sctp.addip_enable)
722                 return retval;
723 
724         sp = sctp_sk(sk);
725         ep = sp->ep;
726 
727         pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
728                  __func__, sk, addrs, addrcnt);
729 
730         list_for_each_entry(asoc, &ep->asocs, asocs) {
731 
732                 if (!asoc->peer.asconf_capable)
733                         continue;
734 
735                 if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
736                         continue;
737 
738                 if (!sctp_state(asoc, ESTABLISHED))
739                         continue;
740 
741                 /* Check if any address in the packed array of addresses is
742                  * not present in the bind address list of the association.
743                  * If so, do not send the asconf chunk to its peer, but
744                  * continue with other associations.
745                  */
746                 addr_buf = addrs;
747                 for (i = 0; i < addrcnt; i++) {
748                         laddr = addr_buf;
749                         af = sctp_get_af_specific(laddr->v4.sin_family);
750                         if (!af) {
751                                 retval = -EINVAL;
752                                 goto out;
753                         }
754 
755                         if (!sctp_assoc_lookup_laddr(asoc, laddr))
756                                 break;
757 
758                         addr_buf += af->sockaddr_len;
759                 }
760                 if (i < addrcnt)
761                         continue;
762 
763                 /* Find one address in the association's bind address list
764                  * that is not in the packed array of addresses. This is to
765                  * make sure that we do not delete all the addresses in the
766                  * association.
767                  */
768                 bp = &asoc->base.bind_addr;
769                 laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
770                                                addrcnt, sp);
771                 if ((laddr == NULL) && (addrcnt == 1)) {
772                         if (asoc->asconf_addr_del_pending)
773                                 continue;
774                         asoc->asconf_addr_del_pending =
775                             kzalloc(sizeof(union sctp_addr), GFP_ATOMIC);
776                         if (asoc->asconf_addr_del_pending == NULL) {
777                                 retval = -ENOMEM;
778                                 goto out;
779                         }
780                         asoc->asconf_addr_del_pending->sa.sa_family =
781                                     addrs->sa_family;
782                         asoc->asconf_addr_del_pending->v4.sin_port =
783                                     htons(bp->port);
784                         if (addrs->sa_family == AF_INET) {
785                                 struct sockaddr_in *sin;
786 
787                                 sin = (struct sockaddr_in *)addrs;
788                                 asoc->asconf_addr_del_pending->v4.sin_addr.s_addr = sin->sin_addr.s_addr;
789                         } else if (addrs->sa_family == AF_INET6) {
790                                 struct sockaddr_in6 *sin6;
791 
792                                 sin6 = (struct sockaddr_in6 *)addrs;
793                                 asoc->asconf_addr_del_pending->v6.sin6_addr = sin6->sin6_addr;
794                         }
795 
796                         pr_debug("%s: keep the last address asoc:%p %pISc at %p\n",
797                                  __func__, asoc, &asoc->asconf_addr_del_pending->sa,
798                                  asoc->asconf_addr_del_pending);
799 
800                         asoc->src_out_of_asoc_ok = 1;
801                         stored = 1;
802                         goto skip_mkasconf;
803                 }
804 
805                 if (laddr == NULL)
806                         return -EINVAL;
807 
808                 /* We do not need RCU protection throughout this loop
809                  * because this is done under a socket lock from the
810                  * setsockopt call.
811                  */
812                 chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
813                                                    SCTP_PARAM_DEL_IP);
814                 if (!chunk) {
815                         retval = -ENOMEM;
816                         goto out;
817                 }
818 
819 skip_mkasconf:
820                 /* Reset use_as_src flag for the addresses in the bind address
821                  * list that are to be deleted.
822                  */
823                 addr_buf = addrs;
824                 for (i = 0; i < addrcnt; i++) {
825                         laddr = addr_buf;
826                         af = sctp_get_af_specific(laddr->v4.sin_family);
827                         list_for_each_entry(saddr, &bp->address_list, list) {
828                                 if (sctp_cmp_addr_exact(&saddr->a, laddr))
829                                         saddr->state = SCTP_ADDR_DEL;
830                         }
831                         addr_buf += af->sockaddr_len;
832                 }
833 
834                 /* Update the route and saddr entries for all the transports
835                  * as some of the addresses in the bind address list are
836                  * about to be deleted and cannot be used as source addresses.
837                  */
838                 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
839                                         transports) {
840                         dst_release(transport->dst);
841                         sctp_transport_route(transport, NULL,
842                                              sctp_sk(asoc->base.sk));
843                 }
844 
845                 if (stored)
846                         /* We don't need to transmit ASCONF */
847                         continue;
848                 retval = sctp_send_asconf(asoc, chunk);
849         }
850 out:
851         return retval;
852 }
853 
854 /* set addr events to assocs in the endpoint.  ep and addr_wq must be locked */
855 int sctp_asconf_mgmt(struct sctp_sock *sp, struct sctp_sockaddr_entry *addrw)
856 {
857         struct sock *sk = sctp_opt2sk(sp);
858         union sctp_addr *addr;
859         struct sctp_af *af;
860 
861         /* It is safe to write port space in caller. */
862         addr = &addrw->a;
863         addr->v4.sin_port = htons(sp->ep->base.bind_addr.port);
864         af = sctp_get_af_specific(addr->sa.sa_family);
865         if (!af)
866                 return -EINVAL;
867         if (sctp_verify_addr(sk, addr, af->sockaddr_len))
868                 return -EINVAL;
869 
870         if (addrw->state == SCTP_ADDR_NEW)
871                 return sctp_send_asconf_add_ip(sk, (struct sockaddr *)addr, 1);
872         else
873                 return sctp_send_asconf_del_ip(sk, (struct sockaddr *)addr, 1);
874 }
875 
876 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
877  *
878  * API 8.1
879  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
880  *                int flags);
881  *
882  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
883  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
884  * or IPv6 addresses.
885  *
886  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
887  * Section 3.1.2 for this usage.
888  *
889  * addrs is a pointer to an array of one or more socket addresses. Each
890  * address is contained in its appropriate structure (i.e. struct
891  * sockaddr_in or struct sockaddr_in6) the family of the address type
892  * must be used to distinguish the address length (note that this
893  * representation is termed a "packed array" of addresses). The caller
894  * specifies the number of addresses in the array with addrcnt.
895  *
896  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
897  * -1, and sets errno to the appropriate error code.
898  *
899  * For SCTP, the port given in each socket address must be the same, or
900  * sctp_bindx() will fail, setting errno to EINVAL.
901  *
902  * The flags parameter is formed from the bitwise OR of zero or more of
903  * the following currently defined flags:
904  *
905  * SCTP_BINDX_ADD_ADDR
906  *
907  * SCTP_BINDX_REM_ADDR
908  *
909  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
910  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
911  * addresses from the association. The two flags are mutually exclusive;
912  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
913  * not remove all addresses from an association; sctp_bindx() will
914  * reject such an attempt with EINVAL.
915  *
916  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
917  * additional addresses with an endpoint after calling bind().  Or use
918  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
919  * socket is associated with so that no new association accepted will be
920  * associated with those addresses. If the endpoint supports dynamic
921  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
922  * endpoint to send the appropriate message to the peer to change the
923  * peers address lists.
924  *
925  * Adding and removing addresses from a connected association is
926  * optional functionality. Implementations that do not support this
927  * functionality should return EOPNOTSUPP.
928  *
929  * Basically do nothing but copying the addresses from user to kernel
930  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
931  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
932  * from userspace.
933  *
934  * We don't use copy_from_user() for optimization: we first do the
935  * sanity checks (buffer size -fast- and access check-healthy
936  * pointer); if all of those succeed, then we can alloc the memory
937  * (expensive operation) needed to copy the data to kernel. Then we do
938  * the copying without checking the user space area
939  * (__copy_from_user()).
940  *
941  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
942  * it.
943  *
944  * sk        The sk of the socket
945  * addrs     The pointer to the addresses in user land
946  * addrssize Size of the addrs buffer
947  * op        Operation to perform (add or remove, see the flags of
948  *           sctp_bindx)
949  *
950  * Returns 0 if ok, <0 errno code on error.
951  */
952 static int sctp_setsockopt_bindx(struct sock *sk,
953                                  struct sockaddr __user *addrs,
954                                  int addrs_size, int op)
955 {
956         struct sockaddr *kaddrs;
957         int err;
958         int addrcnt = 0;
959         int walk_size = 0;
960         struct sockaddr *sa_addr;
961         void *addr_buf;
962         struct sctp_af *af;
963 
964         pr_debug("%s: sk:%p addrs:%p addrs_size:%d opt:%d\n",
965                  __func__, sk, addrs, addrs_size, op);
966 
967         if (unlikely(addrs_size <= 0))
968                 return -EINVAL;
969 
970         /* Check the user passed a healthy pointer.  */
971         if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
972                 return -EFAULT;
973 
974         /* Alloc space for the address array in kernel memory.  */
975         kaddrs = kmalloc(addrs_size, GFP_KERNEL);
976         if (unlikely(!kaddrs))
977                 return -ENOMEM;
978 
979         if (__copy_from_user(kaddrs, addrs, addrs_size)) {
980                 kfree(kaddrs);
981                 return -EFAULT;
982         }
983 
984         /* Walk through the addrs buffer and count the number of addresses. */
985         addr_buf = kaddrs;
986         while (walk_size < addrs_size) {
987                 if (walk_size + sizeof(sa_family_t) > addrs_size) {
988                         kfree(kaddrs);
989                         return -EINVAL;
990                 }
991 
992                 sa_addr = addr_buf;
993                 af = sctp_get_af_specific(sa_addr->sa_family);
994 
995                 /* If the address family is not supported or if this address
996                  * causes the address buffer to overflow return EINVAL.
997                  */
998                 if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
999                         kfree(kaddrs);
1000                         return -EINVAL;
1001                 }
1002                 addrcnt++;
1003                 addr_buf += af->sockaddr_len;
1004                 walk_size += af->sockaddr_len;
1005         }
1006 
1007         /* Do the work. */
1008         switch (op) {
1009         case SCTP_BINDX_ADD_ADDR:
1010                 err = sctp_bindx_add(sk, kaddrs, addrcnt);
1011                 if (err)
1012                         goto out;
1013                 err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
1014                 break;
1015 
1016         case SCTP_BINDX_REM_ADDR:
1017                 err = sctp_bindx_rem(sk, kaddrs, addrcnt);
1018                 if (err)
1019                         goto out;
1020                 err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
1021                 break;
1022 
1023         default:
1024                 err = -EINVAL;
1025                 break;
1026         }
1027 
1028 out:
1029         kfree(kaddrs);
1030 
1031         return err;
1032 }
1033 
1034 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
1035  *
1036  * Common routine for handling connect() and sctp_connectx().
1037  * Connect will come in with just a single address.
1038  */
1039 static int __sctp_connect(struct sock *sk,
1040                           struct sockaddr *kaddrs,
1041                           int addrs_size,
1042                           sctp_assoc_t *assoc_id)
1043 {
1044         struct net *net = sock_net(sk);
1045         struct sctp_sock *sp;
1046         struct sctp_endpoint *ep;
1047         struct sctp_association *asoc = NULL;
1048         struct sctp_association *asoc2;
1049         struct sctp_transport *transport;
1050         union sctp_addr to;
1051         sctp_scope_t scope;
1052         long timeo;
1053         int err = 0;
1054         int addrcnt = 0;
1055         int walk_size = 0;
1056         union sctp_addr *sa_addr = NULL;
1057         void *addr_buf;
1058         unsigned short port;
1059         unsigned int f_flags = 0;
1060 
1061         sp = sctp_sk(sk);
1062         ep = sp->ep;
1063 
1064         /* connect() cannot be done on a socket that is already in ESTABLISHED
1065          * state - UDP-style peeled off socket or a TCP-style socket that
1066          * is already connected.
1067          * It cannot be done even on a TCP-style listening socket.
1068          */
1069         if (sctp_sstate(sk, ESTABLISHED) ||
1070             (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
1071                 err = -EISCONN;
1072                 goto out_free;
1073         }
1074 
1075         /* Walk through the addrs buffer and count the number of addresses. */
1076         addr_buf = kaddrs;
1077         while (walk_size < addrs_size) {
1078                 struct sctp_af *af;
1079 
1080                 if (walk_size + sizeof(sa_family_t) > addrs_size) {
1081                         err = -EINVAL;
1082                         goto out_free;
1083                 }
1084 
1085                 sa_addr = addr_buf;
1086                 af = sctp_get_af_specific(sa_addr->sa.sa_family);
1087 
1088                 /* If the address family is not supported or if this address
1089                  * causes the address buffer to overflow return EINVAL.
1090                  */
1091                 if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1092                         err = -EINVAL;
1093                         goto out_free;
1094                 }
1095 
1096                 port = ntohs(sa_addr->v4.sin_port);
1097 
1098                 /* Save current address so we can work with it */
1099                 memcpy(&to, sa_addr, af->sockaddr_len);
1100 
1101                 err = sctp_verify_addr(sk, &to, af->sockaddr_len);
1102                 if (err)
1103                         goto out_free;
1104 
1105                 /* Make sure the destination port is correctly set
1106                  * in all addresses.
1107                  */
1108                 if (asoc && asoc->peer.port && asoc->peer.port != port) {
1109                         err = -EINVAL;
1110                         goto out_free;
1111                 }
1112 
1113                 /* Check if there already is a matching association on the
1114                  * endpoint (other than the one created here).
1115                  */
1116                 asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1117                 if (asoc2 && asoc2 != asoc) {
1118                         if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1119                                 err = -EISCONN;
1120                         else
1121                                 err = -EALREADY;
1122                         goto out_free;
1123                 }
1124 
1125                 /* If we could not find a matching association on the endpoint,
1126                  * make sure that there is no peeled-off association matching
1127                  * the peer address even on another socket.
1128                  */
1129                 if (sctp_endpoint_is_peeled_off(ep, &to)) {
1130                         err = -EADDRNOTAVAIL;
1131                         goto out_free;
1132                 }
1133 
1134                 if (!asoc) {
1135                         /* If a bind() or sctp_bindx() is not called prior to
1136                          * an sctp_connectx() call, the system picks an
1137                          * ephemeral port and will choose an address set
1138                          * equivalent to binding with a wildcard address.
1139                          */
1140                         if (!ep->base.bind_addr.port) {
1141                                 if (sctp_autobind(sk)) {
1142                                         err = -EAGAIN;
1143                                         goto out_free;
1144                                 }
1145                         } else {
1146                                 /*
1147                                  * If an unprivileged user inherits a 1-many
1148                                  * style socket with open associations on a
1149                                  * privileged port, it MAY be permitted to
1150                                  * accept new associations, but it SHOULD NOT
1151                                  * be permitted to open new associations.
1152                                  */
1153                                 if (ep->base.bind_addr.port < PROT_SOCK &&
1154                                     !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) {
1155                                         err = -EACCES;
1156                                         goto out_free;
1157                                 }
1158                         }
1159 
1160                         scope = sctp_scope(&to);
1161                         asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1162                         if (!asoc) {
1163                                 err = -ENOMEM;
1164                                 goto out_free;
1165                         }
1166 
1167                         err = sctp_assoc_set_bind_addr_from_ep(asoc, scope,
1168                                                               GFP_KERNEL);
1169                         if (err < 0) {
1170                                 goto out_free;
1171                         }
1172 
1173                 }
1174 
1175                 /* Prime the peer's transport structures.  */
1176                 transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
1177                                                 SCTP_UNKNOWN);
1178                 if (!transport) {
1179                         err = -ENOMEM;
1180                         goto out_free;
1181                 }
1182 
1183                 addrcnt++;
1184                 addr_buf += af->sockaddr_len;
1185                 walk_size += af->sockaddr_len;
1186         }
1187 
1188         /* In case the user of sctp_connectx() wants an association
1189          * id back, assign one now.
1190          */
1191         if (assoc_id) {
1192                 err = sctp_assoc_set_id(asoc, GFP_KERNEL);
1193                 if (err < 0)
1194                         goto out_free;
1195         }
1196 
1197         err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
1198         if (err < 0) {
1199                 goto out_free;
1200         }
1201 
1202         /* Initialize sk's dport and daddr for getpeername() */
1203         inet_sk(sk)->inet_dport = htons(asoc->peer.port);
1204         sp->pf->to_sk_daddr(sa_addr, sk);
1205         sk->sk_err = 0;
1206 
1207         /* in-kernel sockets don't generally have a file allocated to them
1208          * if all they do is call sock_create_kern().
1209          */
1210         if (sk->sk_socket->file)
1211                 f_flags = sk->sk_socket->file->f_flags;
1212 
1213         timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
1214 
1215         err = sctp_wait_for_connect(asoc, &timeo);
1216         if ((err == 0 || err == -EINPROGRESS) && assoc_id)
1217                 *assoc_id = asoc->assoc_id;
1218 
1219         /* Don't free association on exit. */
1220         asoc = NULL;
1221 
1222 out_free:
1223         pr_debug("%s: took out_free path with asoc:%p kaddrs:%p err:%d\n",
1224                  __func__, asoc, kaddrs, err);
1225 
1226         if (asoc) {
1227                 /* sctp_primitive_ASSOCIATE may have added this association
1228                  * To the hash table, try to unhash it, just in case, its a noop
1229                  * if it wasn't hashed so we're safe
1230                  */
1231                 sctp_unhash_established(asoc);
1232                 sctp_association_free(asoc);
1233         }
1234         return err;
1235 }
1236 
1237 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1238  *
1239  * API 8.9
1240  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt,
1241  *                      sctp_assoc_t *asoc);
1242  *
1243  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1244  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1245  * or IPv6 addresses.
1246  *
1247  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1248  * Section 3.1.2 for this usage.
1249  *
1250  * addrs is a pointer to an array of one or more socket addresses. Each
1251  * address is contained in its appropriate structure (i.e. struct
1252  * sockaddr_in or struct sockaddr_in6) the family of the address type
1253  * must be used to distengish the address length (note that this
1254  * representation is termed a "packed array" of addresses). The caller
1255  * specifies the number of addresses in the array with addrcnt.
1256  *
1257  * On success, sctp_connectx() returns 0. It also sets the assoc_id to
1258  * the association id of the new association.  On failure, sctp_connectx()
1259  * returns -1, and sets errno to the appropriate error code.  The assoc_id
1260  * is not touched by the kernel.
1261  *
1262  * For SCTP, the port given in each socket address must be the same, or
1263  * sctp_connectx() will fail, setting errno to EINVAL.
1264  *
1265  * An application can use sctp_connectx to initiate an association with
1266  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1267  * allows a caller to specify multiple addresses at which a peer can be
1268  * reached.  The way the SCTP stack uses the list of addresses to set up
1269  * the association is implementation dependent.  This function only
1270  * specifies that the stack will try to make use of all the addresses in
1271  * the list when needed.
1272  *
1273  * Note that the list of addresses passed in is only used for setting up
1274  * the association.  It does not necessarily equal the set of addresses
1275  * the peer uses for the resulting association.  If the caller wants to
1276  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1277  * retrieve them after the association has been set up.
1278  *
1279  * Basically do nothing but copying the addresses from user to kernel
1280  * land and invoking either sctp_connectx(). This is used for tunneling
1281  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1282  *
1283  * We don't use copy_from_user() for optimization: we first do the
1284  * sanity checks (buffer size -fast- and access check-healthy
1285  * pointer); if all of those succeed, then we can alloc the memory
1286  * (expensive operation) needed to copy the data to kernel. Then we do
1287  * the copying without checking the user space area
1288  * (__copy_from_user()).
1289  *
1290  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1291  * it.
1292  *
1293  * sk        The sk of the socket
1294  * addrs     The pointer to the addresses in user land
1295  * addrssize Size of the addrs buffer
1296  *
1297  * Returns >=0 if ok, <0 errno code on error.
1298  */
1299 static int __sctp_setsockopt_connectx(struct sock *sk,
1300                                       struct sockaddr __user *addrs,
1301                                       int addrs_size,
1302                                       sctp_assoc_t *assoc_id)
1303 {
1304         int err = 0;
1305         struct sockaddr *kaddrs;
1306 
1307         pr_debug("%s: sk:%p addrs:%p addrs_size:%d\n",
1308                  __func__, sk, addrs, addrs_size);
1309 
1310         if (unlikely(addrs_size <= 0))
1311                 return -EINVAL;
1312 
1313         /* Check the user passed a healthy pointer.  */
1314         if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1315                 return -EFAULT;
1316 
1317         /* Alloc space for the address array in kernel memory.  */
1318         kaddrs = kmalloc(addrs_size, GFP_KERNEL);
1319         if (unlikely(!kaddrs))
1320                 return -ENOMEM;
1321 
1322         if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1323                 err = -EFAULT;
1324         } else {
1325                 err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
1326         }
1327 
1328         kfree(kaddrs);
1329 
1330         return err;
1331 }
1332 
1333 /*
1334  * This is an older interface.  It's kept for backward compatibility
1335  * to the option that doesn't provide association id.
1336  */
1337 static int sctp_setsockopt_connectx_old(struct sock *sk,
1338                                         struct sockaddr __user *addrs,
1339                                         int addrs_size)
1340 {
1341         return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL);
1342 }
1343 
1344 /*
1345  * New interface for the API.  The since the API is done with a socket
1346  * option, to make it simple we feed back the association id is as a return
1347  * indication to the call.  Error is always negative and association id is
1348  * always positive.
1349  */
1350 static int sctp_setsockopt_connectx(struct sock *sk,
1351                                     struct sockaddr __user *addrs,
1352                                     int addrs_size)
1353 {
1354         sctp_assoc_t assoc_id = 0;
1355         int err = 0;
1356 
1357         err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id);
1358 
1359         if (err)
1360                 return err;
1361         else
1362                 return assoc_id;
1363 }
1364 
1365 /*
1366  * New (hopefully final) interface for the API.
1367  * We use the sctp_getaddrs_old structure so that use-space library
1368  * can avoid any unnecessary allocations. The only different part
1369  * is that we store the actual length of the address buffer into the
1370  * addrs_num structure member. That way we can re-use the existing
1371  * code.
1372  */
1373 #ifdef CONFIG_COMPAT
1374 struct compat_sctp_getaddrs_old {
1375         sctp_assoc_t    assoc_id;
1376         s32             addr_num;
1377         compat_uptr_t   addrs;          /* struct sockaddr * */
1378 };
1379 #endif
1380 
1381 static int sctp_getsockopt_connectx3(struct sock *sk, int len,
1382                                      char __user *optval,
1383                                      int __user *optlen)
1384 {
1385         struct sctp_getaddrs_old param;
1386         sctp_assoc_t assoc_id = 0;
1387         int err = 0;
1388 
1389 #ifdef CONFIG_COMPAT
1390         if (is_compat_task()) {
1391                 struct compat_sctp_getaddrs_old param32;
1392 
1393                 if (len < sizeof(param32))
1394                         return -EINVAL;
1395                 if (copy_from_user(&param32, optval, sizeof(param32)))
1396                         return -EFAULT;
1397 
1398                 param.assoc_id = param32.assoc_id;
1399                 param.addr_num = param32.addr_num;
1400                 param.addrs = compat_ptr(param32.addrs);
1401         } else
1402 #endif
1403         {
1404                 if (len < sizeof(param))
1405                         return -EINVAL;
1406                 if (copy_from_user(&param, optval, sizeof(param)))
1407                         return -EFAULT;
1408         }
1409 
1410         err = __sctp_setsockopt_connectx(sk, (struct sockaddr __user *)
1411                                          param.addrs, param.addr_num,
1412                                          &assoc_id);
1413         if (err == 0 || err == -EINPROGRESS) {
1414                 if (copy_to_user(optval, &assoc_id, sizeof(assoc_id)))
1415                         return -EFAULT;
1416                 if (put_user(sizeof(assoc_id), optlen))
1417                         return -EFAULT;
1418         }
1419 
1420         return err;
1421 }
1422 
1423 /* API 3.1.4 close() - UDP Style Syntax
1424  * Applications use close() to perform graceful shutdown (as described in
1425  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1426  * by a UDP-style socket.
1427  *
1428  * The syntax is
1429  *
1430  *   ret = close(int sd);
1431  *
1432  *   sd      - the socket descriptor of the associations to be closed.
1433  *
1434  * To gracefully shutdown a specific association represented by the
1435  * UDP-style socket, an application should use the sendmsg() call,
1436  * passing no user data, but including the appropriate flag in the
1437  * ancillary data (see Section xxxx).
1438  *
1439  * If sd in the close() call is a branched-off socket representing only
1440  * one association, the shutdown is performed on that association only.
1441  *
1442  * 4.1.6 close() - TCP Style Syntax
1443  *
1444  * Applications use close() to gracefully close down an association.
1445  *
1446  * The syntax is:
1447  *
1448  *    int close(int sd);
1449  *
1450  *      sd      - the socket descriptor of the association to be closed.
1451  *
1452  * After an application calls close() on a socket descriptor, no further
1453  * socket operations will succeed on that descriptor.
1454  *
1455  * API 7.1.4 SO_LINGER
1456  *
1457  * An application using the TCP-style socket can use this option to
1458  * perform the SCTP ABORT primitive.  The linger option structure is:
1459  *
1460  *  struct  linger {
1461  *     int     l_onoff;                // option on/off
1462  *     int     l_linger;               // linger time
1463  * };
1464  *
1465  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1466  * to 0, calling close() is the same as the ABORT primitive.  If the
1467  * value is set to a negative value, the setsockopt() call will return
1468  * an error.  If the value is set to a positive value linger_time, the
1469  * close() can be blocked for at most linger_time ms.  If the graceful
1470  * shutdown phase does not finish during this period, close() will
1471  * return but the graceful shutdown phase continues in the system.
1472  */
1473 static void sctp_close(struct sock *sk, long timeout)
1474 {
1475         struct net *net = sock_net(sk);
1476         struct sctp_endpoint *ep;
1477         struct sctp_association *asoc;
1478         struct list_head *pos, *temp;
1479         unsigned int data_was_unread;
1480 
1481         pr_debug("%s: sk:%p, timeout:%ld\n", __func__, sk, timeout);
1482 
1483         lock_sock(sk);
1484         sk->sk_shutdown = SHUTDOWN_MASK;
1485         sk->sk_state = SCTP_SS_CLOSING;
1486 
1487         ep = sctp_sk(sk)->ep;
1488 
1489         /* Clean up any skbs sitting on the receive queue.  */
1490         data_was_unread = sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1491         data_was_unread += sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1492 
1493         /* Walk all associations on an endpoint.  */
1494         list_for_each_safe(pos, temp, &ep->asocs) {
1495                 asoc = list_entry(pos, struct sctp_association, asocs);
1496 
1497                 if (sctp_style(sk, TCP)) {
1498                         /* A closed association can still be in the list if
1499                          * it belongs to a TCP-style listening socket that is
1500                          * not yet accepted. If so, free it. If not, send an
1501                          * ABORT or SHUTDOWN based on the linger options.
1502                          */
1503                         if (sctp_state(asoc, CLOSED)) {
1504                                 sctp_unhash_established(asoc);
1505                                 sctp_association_free(asoc);
1506                                 continue;
1507                         }
1508                 }
1509 
1510                 if (data_was_unread || !skb_queue_empty(&asoc->ulpq.lobby) ||
1511                     !skb_queue_empty(&asoc->ulpq.reasm) ||
1512                     (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime)) {
1513                         struct sctp_chunk *chunk;
1514 
1515                         chunk = sctp_make_abort_user(asoc, NULL, 0);
1516                         if (chunk)
1517                                 sctp_primitive_ABORT(net, asoc, chunk);
1518                 } else
1519                         sctp_primitive_SHUTDOWN(net, asoc, NULL);
1520         }
1521 
1522         /* On a TCP-style socket, block for at most linger_time if set. */
1523         if (sctp_style(sk, TCP) && timeout)
1524                 sctp_wait_for_close(sk, timeout);
1525 
1526         /* This will run the backlog queue.  */
1527         release_sock(sk);
1528 
1529         /* Supposedly, no process has access to the socket, but
1530          * the net layers still may.
1531          * Also, sctp_destroy_sock() needs to be called with addr_wq_lock
1532          * held and that should be grabbed before socket lock.
1533          */
1534         spin_lock_bh(&net->sctp.addr_wq_lock);
1535         bh_lock_sock(sk);
1536 
1537         /* Hold the sock, since sk_common_release() will put sock_put()
1538          * and we have just a little more cleanup.
1539          */
1540         sock_hold(sk);
1541         sk_common_release(sk);
1542 
1543         bh_unlock_sock(sk);
1544         spin_unlock_bh(&net->sctp.addr_wq_lock);
1545 
1546         sock_put(sk);
1547 
1548         SCTP_DBG_OBJCNT_DEC(sock);
1549 }
1550 
1551 /* Handle EPIPE error. */
1552 static int sctp_error(struct sock *sk, int flags, int err)
1553 {
1554         if (err == -EPIPE)
1555                 err = sock_error(sk) ? : -EPIPE;
1556         if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1557                 send_sig(SIGPIPE, current, 0);
1558         return err;
1559 }
1560 
1561 /* API 3.1.3 sendmsg() - UDP Style Syntax
1562  *
1563  * An application uses sendmsg() and recvmsg() calls to transmit data to
1564  * and receive data from its peer.
1565  *
1566  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1567  *                  int flags);
1568  *
1569  *  socket  - the socket descriptor of the endpoint.
1570  *  message - pointer to the msghdr structure which contains a single
1571  *            user message and possibly some ancillary data.
1572  *
1573  *            See Section 5 for complete description of the data
1574  *            structures.
1575  *
1576  *  flags   - flags sent or received with the user message, see Section
1577  *            5 for complete description of the flags.
1578  *
1579  * Note:  This function could use a rewrite especially when explicit
1580  * connect support comes in.
1581  */
1582 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1583 
1584 static int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1585 
1586 static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
1587 {
1588         struct net *net = sock_net(sk);
1589         struct sctp_sock *sp;
1590         struct sctp_endpoint *ep;
1591         struct sctp_association *new_asoc = NULL, *asoc = NULL;
1592         struct sctp_transport *transport, *chunk_tp;
1593         struct sctp_chunk *chunk;
1594         union sctp_addr to;
1595         struct sockaddr *msg_name = NULL;
1596         struct sctp_sndrcvinfo default_sinfo;
1597         struct sctp_sndrcvinfo *sinfo;
1598         struct sctp_initmsg *sinit;
1599         sctp_assoc_t associd = 0;
1600         sctp_cmsgs_t cmsgs = { NULL };
1601         sctp_scope_t scope;
1602         bool fill_sinfo_ttl = false, wait_connect = false;
1603         struct sctp_datamsg *datamsg;
1604         int msg_flags = msg->msg_flags;
1605         __u16 sinfo_flags = 0;
1606         long timeo;
1607         int err;
1608 
1609         err = 0;
1610         sp = sctp_sk(sk);
1611         ep = sp->ep;
1612 
1613         pr_debug("%s: sk:%p, msg:%p, msg_len:%zu ep:%p\n", __func__, sk,
1614                  msg, msg_len, ep);
1615 
1616         /* We cannot send a message over a TCP-style listening socket. */
1617         if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1618                 err = -EPIPE;
1619                 goto out_nounlock;
1620         }
1621 
1622         /* Parse out the SCTP CMSGs.  */
1623         err = sctp_msghdr_parse(msg, &cmsgs);
1624         if (err) {
1625                 pr_debug("%s: msghdr parse err:%x\n", __func__, err);
1626                 goto out_nounlock;
1627         }
1628 
1629         /* Fetch the destination address for this packet.  This
1630          * address only selects the association--it is not necessarily
1631          * the address we will send to.
1632          * For a peeled-off socket, msg_name is ignored.
1633          */
1634         if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1635                 int msg_namelen = msg->msg_namelen;
1636 
1637                 err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1638                                        msg_namelen);
1639                 if (err)
1640                         return err;
1641 
1642                 if (msg_namelen > sizeof(to))
1643                         msg_namelen = sizeof(to);
1644                 memcpy(&to, msg->msg_name, msg_namelen);
1645                 msg_name = msg->msg_name;
1646         }
1647 
1648         sinit = cmsgs.init;
1649         if (cmsgs.sinfo != NULL) {
1650                 memset(&default_sinfo, 0, sizeof(default_sinfo));
1651                 default_sinfo.sinfo_stream = cmsgs.sinfo->snd_sid;
1652                 default_sinfo.sinfo_flags = cmsgs.sinfo->snd_flags;
1653                 default_sinfo.sinfo_ppid = cmsgs.sinfo->snd_ppid;
1654                 default_sinfo.sinfo_context = cmsgs.sinfo->snd_context;
1655                 default_sinfo.sinfo_assoc_id = cmsgs.sinfo->snd_assoc_id;
1656 
1657                 sinfo = &default_sinfo;
1658                 fill_sinfo_ttl = true;
1659         } else {
1660                 sinfo = cmsgs.srinfo;
1661         }
1662         /* Did the user specify SNDINFO/SNDRCVINFO? */
1663         if (sinfo) {
1664                 sinfo_flags = sinfo->sinfo_flags;
1665                 associd = sinfo->sinfo_assoc_id;
1666         }
1667 
1668         pr_debug("%s: msg_len:%zu, sinfo_flags:0x%x\n", __func__,
1669                  msg_len, sinfo_flags);
1670 
1671         /* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1672         if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1673                 err = -EINVAL;
1674                 goto out_nounlock;
1675         }
1676 
1677         /* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1678          * length messages when SCTP_EOF|SCTP_ABORT is not set.
1679          * If SCTP_ABORT is set, the message length could be non zero with
1680          * the msg_iov set to the user abort reason.
1681          */
1682         if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1683             (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1684                 err = -EINVAL;
1685                 goto out_nounlock;
1686         }
1687 
1688         /* If SCTP_ADDR_OVER is set, there must be an address
1689          * specified in msg_name.
1690          */
1691         if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1692                 err = -EINVAL;
1693                 goto out_nounlock;
1694         }
1695 
1696         transport = NULL;
1697 
1698         pr_debug("%s: about to look up association\n", __func__);
1699 
1700         lock_sock(sk);
1701 
1702         /* If a msg_name has been specified, assume this is to be used.  */
1703         if (msg_name) {
1704                 /* Look for a matching association on the endpoint. */
1705                 asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1706                 if (!asoc) {
1707                         /* If we could not find a matching association on the
1708                          * endpoint, make sure that it is not a TCP-style
1709                          * socket that already has an association or there is
1710                          * no peeled-off association on another socket.
1711                          */
1712                         if ((sctp_style(sk, TCP) &&
1713                              sctp_sstate(sk, ESTABLISHED)) ||
1714                             sctp_endpoint_is_peeled_off(ep, &to)) {
1715                                 err = -EADDRNOTAVAIL;
1716                                 goto out_unlock;
1717                         }
1718                 }
1719         } else {
1720                 asoc = sctp_id2assoc(sk, associd);
1721                 if (!asoc) {
1722                         err = -EPIPE;
1723                         goto out_unlock;
1724                 }
1725         }
1726 
1727         if (asoc) {
1728                 pr_debug("%s: just looked up association:%p\n", __func__, asoc);
1729 
1730                 /* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1731                  * socket that has an association in CLOSED state. This can
1732                  * happen when an accepted socket has an association that is
1733                  * already CLOSED.
1734                  */
1735                 if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1736                         err = -EPIPE;
1737                         goto out_unlock;
1738                 }
1739 
1740                 if (sinfo_flags & SCTP_EOF) {
1741                         pr_debug("%s: shutting down association:%p\n",
1742                                  __func__, asoc);
1743 
1744                         sctp_primitive_SHUTDOWN(net, asoc, NULL);
1745                         err = 0;
1746                         goto out_unlock;
1747                 }
1748                 if (sinfo_flags & SCTP_ABORT) {
1749 
1750                         chunk = sctp_make_abort_user(asoc, msg, msg_len);
1751                         if (!chunk) {
1752                                 err = -ENOMEM;
1753                                 goto out_unlock;
1754                         }
1755 
1756                         pr_debug("%s: aborting association:%p\n",
1757                                  __func__, asoc);
1758 
1759                         sctp_primitive_ABORT(net, asoc, chunk);
1760                         err = 0;
1761                         goto out_unlock;
1762                 }
1763         }
1764 
1765         /* Do we need to create the association?  */
1766         if (!asoc) {
1767                 pr_debug("%s: there is no association yet\n", __func__);
1768 
1769                 if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1770                         err = -EINVAL;
1771                         goto out_unlock;
1772                 }
1773 
1774                 /* Check for invalid stream against the stream counts,
1775                  * either the default or the user specified stream counts.
1776                  */
1777                 if (sinfo) {
1778                         if (!sinit || !sinit->sinit_num_ostreams) {
1779                                 /* Check against the defaults. */
1780                                 if (sinfo->sinfo_stream >=
1781                                     sp->initmsg.sinit_num_ostreams) {
1782                                         err = -EINVAL;
1783                                         goto out_unlock;
1784                                 }
1785                         } else {
1786                                 /* Check against the requested.  */
1787                                 if (sinfo->sinfo_stream >=
1788                                     sinit->sinit_num_ostreams) {
1789                                         err = -EINVAL;
1790                                         goto out_unlock;
1791                                 }
1792                         }
1793                 }
1794 
1795                 /*
1796                  * API 3.1.2 bind() - UDP Style Syntax
1797                  * If a bind() or sctp_bindx() is not called prior to a
1798                  * sendmsg() call that initiates a new association, the
1799                  * system picks an ephemeral port and will choose an address
1800                  * set equivalent to binding with a wildcard address.
1801                  */
1802                 if (!ep->base.bind_addr.port) {
1803                         if (sctp_autobind(sk)) {
1804                                 err = -EAGAIN;
1805                                 goto out_unlock;
1806                         }
1807                 } else {
1808                         /*
1809                          * If an unprivileged user inherits a one-to-many
1810                          * style socket with open associations on a privileged
1811                          * port, it MAY be permitted to accept new associations,
1812                          * but it SHOULD NOT be permitted to open new
1813                          * associations.
1814                          */
1815                         if (ep->base.bind_addr.port < PROT_SOCK &&
1816                             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) {
1817                                 err = -EACCES;
1818                                 goto out_unlock;
1819                         }
1820                 }
1821 
1822                 scope = sctp_scope(&to);
1823                 new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1824                 if (!new_asoc) {
1825                         err = -ENOMEM;
1826                         goto out_unlock;
1827                 }
1828                 asoc = new_asoc;
1829                 err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL);
1830                 if (err < 0) {
1831                         err = -ENOMEM;
1832                         goto out_free;
1833                 }
1834 
1835                 /* If the SCTP_INIT ancillary data is specified, set all
1836                  * the association init values accordingly.
1837                  */
1838                 if (sinit) {
1839                         if (sinit->sinit_num_ostreams) {
1840                                 asoc->c.sinit_num_ostreams =
1841                                         sinit->sinit_num_ostreams;
1842                         }
1843                         if (sinit->sinit_max_instreams) {
1844                                 asoc->c.sinit_max_instreams =
1845                                         sinit->sinit_max_instreams;
1846                         }
1847                         if (sinit->sinit_max_attempts) {
1848                                 asoc->max_init_attempts
1849                                         = sinit->sinit_max_attempts;
1850                         }
1851                         if (sinit->sinit_max_init_timeo) {
1852                                 asoc->max_init_timeo =
1853                                  msecs_to_jiffies(sinit->sinit_max_init_timeo);
1854                         }
1855                 }
1856 
1857                 /* Prime the peer's transport structures.  */
1858                 transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1859                 if (!transport) {
1860                         err = -ENOMEM;
1861                         goto out_free;
1862                 }
1863         }
1864 
1865         /* ASSERT: we have a valid association at this point.  */
1866         pr_debug("%s: we have a valid association\n", __func__);
1867 
1868         if (!sinfo) {
1869                 /* If the user didn't specify SNDINFO/SNDRCVINFO, make up
1870                  * one with some defaults.
1871                  */
1872                 memset(&default_sinfo, 0, sizeof(default_sinfo));
1873                 default_sinfo.sinfo_stream = asoc->default_stream;
1874                 default_sinfo.sinfo_flags = asoc->default_flags;
1875                 default_sinfo.sinfo_ppid = asoc->default_ppid;
1876                 default_sinfo.sinfo_context = asoc->default_context;
1877                 default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1878                 default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1879 
1880                 sinfo = &default_sinfo;
1881         } else if (fill_sinfo_ttl) {
1882                 /* In case SNDINFO was specified, we still need to fill
1883                  * it with a default ttl from the assoc here.
1884                  */
1885                 sinfo->sinfo_timetolive = asoc->default_timetolive;
1886         }
1887 
1888         /* API 7.1.7, the sndbuf size per association bounds the
1889          * maximum size of data that can be sent in a single send call.
1890          */
1891         if (msg_len > sk->sk_sndbuf) {
1892                 err = -EMSGSIZE;
1893                 goto out_free;
1894         }
1895 
1896         if (asoc->pmtu_pending)
1897                 sctp_assoc_pending_pmtu(sk, asoc);
1898 
1899         /* If fragmentation is disabled and the message length exceeds the
1900          * association fragmentation point, return EMSGSIZE.  The I-D
1901          * does not specify what this error is, but this looks like
1902          * a great fit.
1903          */
1904         if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1905                 err = -EMSGSIZE;
1906                 goto out_free;
1907         }
1908 
1909         /* Check for invalid stream. */
1910         if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
1911                 err = -EINVAL;
1912                 goto out_free;
1913         }
1914 
1915         timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1916         if (!sctp_wspace(asoc)) {
1917                 err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1918                 if (err)
1919                         goto out_free;
1920         }
1921 
1922         /* If an address is passed with the sendto/sendmsg call, it is used
1923          * to override the primary destination address in the TCP model, or
1924          * when SCTP_ADDR_OVER flag is set in the UDP model.
1925          */
1926         if ((sctp_style(sk, TCP) && msg_name) ||
1927             (sinfo_flags & SCTP_ADDR_OVER)) {
1928                 chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1929                 if (!chunk_tp) {
1930                         err = -EINVAL;
1931                         goto out_free;
1932                 }
1933         } else
1934                 chunk_tp = NULL;
1935 
1936         /* Auto-connect, if we aren't connected already. */
1937         if (sctp_state(asoc, CLOSED)) {
1938                 err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
1939                 if (err < 0)
1940                         goto out_free;
1941 
1942                 wait_connect = true;
1943                 pr_debug("%s: we associated primitively\n", __func__);
1944         }
1945 
1946         /* Break the message into multiple chunks of maximum size. */
1947         datamsg = sctp_datamsg_from_user(asoc, sinfo, &msg->msg_iter);
1948         if (IS_ERR(datamsg)) {
1949                 err = PTR_ERR(datamsg);
1950                 goto out_free;
1951         }
1952 
1953         /* Now send the (possibly) fragmented message. */
1954         list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
1955                 sctp_chunk_hold(chunk);
1956 
1957                 /* Do accounting for the write space.  */
1958                 sctp_set_owner_w(chunk);
1959 
1960                 chunk->transport = chunk_tp;
1961         }
1962 
1963         /* Send it to the lower layers.  Note:  all chunks
1964          * must either fail or succeed.   The lower layer
1965          * works that way today.  Keep it that way or this
1966          * breaks.
1967          */
1968         err = sctp_primitive_SEND(net, asoc, datamsg);
1969         /* Did the lower layer accept the chunk? */
1970         if (err) {
1971                 sctp_datamsg_free(datamsg);
1972                 goto out_free;
1973         }
1974 
1975         pr_debug("%s: we sent primitively\n", __func__);
1976 
1977         sctp_datamsg_put(datamsg);
1978         err = msg_len;
1979 
1980         if (unlikely(wait_connect)) {
1981                 timeo = sock_sndtimeo(sk, msg_flags & MSG_DONTWAIT);
1982                 sctp_wait_for_connect(asoc, &timeo);
1983         }
1984 
1985         /* If we are already past ASSOCIATE, the lower
1986          * layers are responsible for association cleanup.
1987          */
1988         goto out_unlock;
1989 
1990 out_free:
1991         if (new_asoc) {
1992                 sctp_unhash_established(asoc);
1993                 sctp_association_free(asoc);
1994         }
1995 out_unlock:
1996         release_sock(sk);
1997 
1998 out_nounlock:
1999         return sctp_error(sk, msg_flags, err);
2000 
2001 #if 0
2002 do_sock_err:
2003         if (msg_len)
2004                 err = msg_len;
2005         else
2006                 err = sock_error(sk);
2007         goto out;
2008 
2009 do_interrupted:
2010         if (msg_len)
2011                 err = msg_len;
2012         goto out;
2013 #endif /* 0 */
2014 }
2015 
2016 /* This is an extended version of skb_pull() that removes the data from the
2017  * start of a skb even when data is spread across the list of skb's in the
2018  * frag_list. len specifies the total amount of data that needs to be removed.
2019  * when 'len' bytes could be removed from the skb, it returns 0.
2020  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
2021  * could not be removed.
2022  */
2023 static int sctp_skb_pull(struct sk_buff *skb, int len)
2024 {
2025         struct sk_buff *list;
2026         int skb_len = skb_headlen(skb);
2027         int rlen;
2028 
2029         if (len <= skb_len) {
2030                 __skb_pull(skb, len);
2031                 return 0;
2032         }
2033         len -= skb_len;
2034         __skb_pull(skb, skb_len);
2035 
2036         skb_walk_frags(skb, list) {
2037                 rlen = sctp_skb_pull(list, len);
2038                 skb->len -= (len-rlen);
2039                 skb->data_len -= (len-rlen);
2040 
2041                 if (!rlen)
2042                         return 0;
2043 
2044                 len = rlen;
2045         }
2046 
2047         return len;
2048 }
2049 
2050 /* API 3.1.3  recvmsg() - UDP Style Syntax
2051  *
2052  *  ssize_t recvmsg(int socket, struct msghdr *message,
2053  *                    int flags);
2054  *
2055  *  socket  - the socket descriptor of the endpoint.
2056  *  message - pointer to the msghdr structure which contains a single
2057  *            user message and possibly some ancillary data.
2058  *
2059  *            See Section 5 for complete description of the data
2060  *            structures.
2061  *
2062  *  flags   - flags sent or received with the user message, see Section
2063  *            5 for complete description of the flags.
2064  */
2065 static int sctp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
2066                         int noblock, int flags, int *addr_len)
2067 {
2068         struct sctp_ulpevent *event = NULL;
2069         struct sctp_sock *sp = sctp_sk(sk);
2070         struct sk_buff *skb;
2071         int copied;
2072         int err = 0;
2073         int skb_len;
2074 
2075         pr_debug("%s: sk:%p, msghdr:%p, len:%zd, noblock:%d, flags:0x%x, "
2076                  "addr_len:%p)\n", __func__, sk, msg, len, noblock, flags,
2077                  addr_len);
2078 
2079         lock_sock(sk);
2080 
2081         if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) {
2082                 err = -ENOTCONN;
2083                 goto out;
2084         }
2085 
2086         skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
2087         if (!skb)
2088                 goto out;
2089 
2090         /* Get the total length of the skb including any skb's in the
2091          * frag_list.
2092          */
2093         skb_len = skb->len;
2094 
2095         copied = skb_len;
2096         if (copied > len)
2097                 copied = len;
2098 
2099         err = skb_copy_datagram_msg(skb, 0, msg, copied);
2100 
2101         event = sctp_skb2event(skb);
2102 
2103         if (err)
2104                 goto out_free;
2105 
2106         sock_recv_ts_and_drops(msg, sk, skb);
2107         if (sctp_ulpevent_is_notification(event)) {
2108                 msg->msg_flags |= MSG_NOTIFICATION;
2109                 sp->pf->event_msgname(event, msg->msg_name, addr_len);
2110         } else {
2111                 sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
2112         }
2113 
2114         /* Check if we allow SCTP_NXTINFO. */
2115         if (sp->recvnxtinfo)
2116                 sctp_ulpevent_read_nxtinfo(event, msg, sk);
2117         /* Check if we allow SCTP_RCVINFO. */
2118         if (sp->recvrcvinfo)
2119                 sctp_ulpevent_read_rcvinfo(event, msg);
2120         /* Check if we allow SCTP_SNDRCVINFO. */
2121         if (sp->subscribe.sctp_data_io_event)
2122                 sctp_ulpevent_read_sndrcvinfo(event, msg);
2123 
2124         err = copied;
2125 
2126         /* If skb's length exceeds the user's buffer, update the skb and
2127          * push it back to the receive_queue so that the next call to
2128          * recvmsg() will return the remaining data. Don't set MSG_EOR.
2129          */
2130         if (skb_len > copied) {
2131                 msg->msg_flags &= ~MSG_EOR;
2132                 if (flags & MSG_PEEK)
2133                         goto out_free;
2134                 sctp_skb_pull(skb, copied);
2135                 skb_queue_head(&sk->sk_receive_queue, skb);
2136 
2137                 /* When only partial message is copied to the user, increase
2138                  * rwnd by that amount. If all the data in the skb is read,
2139                  * rwnd is updated when the event is freed.
2140                  */
2141                 if (!sctp_ulpevent_is_notification(event))
2142                         sctp_assoc_rwnd_increase(event->asoc, copied);
2143                 goto out;
2144         } else if ((event->msg_flags & MSG_NOTIFICATION) ||
2145                    (event->msg_flags & MSG_EOR))
2146                 msg->msg_flags |= MSG_EOR;
2147         else
2148                 msg->msg_flags &= ~MSG_EOR;
2149 
2150 out_free:
2151         if (flags & MSG_PEEK) {
2152                 /* Release the skb reference acquired after peeking the skb in
2153                  * sctp_skb_recv_datagram().
2154                  */
2155                 kfree_skb(skb);
2156         } else {
2157                 /* Free the event which includes releasing the reference to
2158                  * the owner of the skb, freeing the skb and updating the
2159                  * rwnd.
2160                  */
2161                 sctp_ulpevent_free(event);
2162         }
2163 out:
2164         release_sock(sk);
2165         return err;
2166 }
2167 
2168 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
2169  *
2170  * This option is a on/off flag.  If enabled no SCTP message
2171  * fragmentation will be performed.  Instead if a message being sent
2172  * exceeds the current PMTU size, the message will NOT be sent and
2173  * instead a error will be indicated to the user.
2174  */
2175 static int sctp_setsockopt_disable_fragments(struct sock *sk,
2176                                              char __user *optval,
2177                                              unsigned int optlen)
2178 {
2179         int val;
2180 
2181         if (optlen < sizeof(int))
2182                 return -EINVAL;
2183 
2184         if (get_user(val, (int __user *)optval))
2185                 return -EFAULT;
2186 
2187         sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
2188 
2189         return 0;
2190 }
2191 
2192 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
2193                                   unsigned int optlen)
2194 {
2195         struct sctp_association *asoc;
2196         struct sctp_ulpevent *event;
2197 
2198         if (optlen > sizeof(struct sctp_event_subscribe))
2199                 return -EINVAL;
2200         if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
2201                 return -EFAULT;
2202 
2203         /* At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
2204          * if there is no data to be sent or retransmit, the stack will
2205          * immediately send up this notification.
2206          */
2207         if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT,
2208                                        &sctp_sk(sk)->subscribe)) {
2209                 asoc = sctp_id2assoc(sk, 0);
2210 
2211                 if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
2212                         event = sctp_ulpevent_make_sender_dry_event(asoc,
2213                                         GFP_ATOMIC);
2214                         if (!event)
2215                                 return -ENOMEM;
2216 
2217                         sctp_ulpq_tail_event(&asoc->ulpq, event);
2218                 }
2219         }
2220 
2221         return 0;
2222 }
2223 
2224 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
2225  *
2226  * This socket option is applicable to the UDP-style socket only.  When
2227  * set it will cause associations that are idle for more than the
2228  * specified number of seconds to automatically close.  An association
2229  * being idle is defined an association that has NOT sent or received
2230  * user data.  The special value of '' indicates that no automatic
2231  * close of any associations should be performed.  The option expects an
2232  * integer defining the number of seconds of idle time before an
2233  * association is closed.
2234  */
2235 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
2236                                      unsigned int optlen)
2237 {
2238         struct sctp_sock *sp = sctp_sk(sk);
2239         struct net *net = sock_net(sk);
2240 
2241         /* Applicable to UDP-style socket only */
2242         if (sctp_style(sk, TCP))
2243                 return -EOPNOTSUPP;
2244         if (optlen != sizeof(int))
2245                 return -EINVAL;
2246         if (copy_from_user(&sp->autoclose, optval, optlen))
2247                 return -EFAULT;
2248 
2249         if (sp->autoclose > net->sctp.max_autoclose)
2250                 sp->autoclose = net->sctp.max_autoclose;
2251 
2252         return 0;
2253 }
2254 
2255 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
2256  *
2257  * Applications can enable or disable heartbeats for any peer address of
2258  * an association, modify an address's heartbeat interval, force a
2259  * heartbeat to be sent immediately, and adjust the address's maximum
2260  * number of retransmissions sent before an address is considered
2261  * unreachable.  The following structure is used to access and modify an
2262  * address's parameters:
2263  *
2264  *  struct sctp_paddrparams {
2265  *     sctp_assoc_t            spp_assoc_id;
2266  *     struct sockaddr_storage spp_address;
2267  *     uint32_t                spp_hbinterval;
2268  *     uint16_t                spp_pathmaxrxt;
2269  *     uint32_t                spp_pathmtu;
2270  *     uint32_t                spp_sackdelay;
2271  *     uint32_t                spp_flags;
2272  * };
2273  *
2274  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2275  *                     application, and identifies the association for
2276  *                     this query.
2277  *   spp_address     - This specifies which address is of interest.
2278  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2279  *                     in milliseconds.  If a  value of zero
2280  *                     is present in this field then no changes are to
2281  *                     be made to this parameter.
2282  *   spp_pathmaxrxt  - This contains the maximum number of
2283  *                     retransmissions before this address shall be
2284  *                     considered unreachable. If a  value of zero
2285  *                     is present in this field then no changes are to
2286  *                     be made to this parameter.
2287  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2288  *                     specified here will be the "fixed" path mtu.
2289  *                     Note that if the spp_address field is empty
2290  *                     then all associations on this address will
2291  *                     have this fixed path mtu set upon them.
2292  *
2293  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2294  *                     the number of milliseconds that sacks will be delayed
2295  *                     for. This value will apply to all addresses of an
2296  *                     association if the spp_address field is empty. Note
2297  *                     also, that if delayed sack is enabled and this
2298  *                     value is set to 0, no change is made to the last
2299  *                     recorded delayed sack timer value.
2300  *
2301  *   spp_flags       - These flags are used to control various features
2302  *                     on an association. The flag field may contain
2303  *                     zero or more of the following options.
2304  *
2305  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2306  *                     specified address. Note that if the address
2307  *                     field is empty all addresses for the association
2308  *                     have heartbeats enabled upon them.
2309  *
2310  *                     SPP_HB_DISABLE - Disable heartbeats on the
2311  *                     speicifed address. Note that if the address
2312  *                     field is empty all addresses for the association
2313  *                     will have their heartbeats disabled. Note also
2314  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2315  *                     mutually exclusive, only one of these two should
2316  *                     be specified. Enabling both fields will have
2317  *                     undetermined results.
2318  *
2319  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2320  *                     to be made immediately.
2321  *
2322  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2323  *                     heartbeat delayis to be set to the value of 0
2324  *                     milliseconds.
2325  *
2326  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2327  *                     discovery upon the specified address. Note that
2328  *                     if the address feild is empty then all addresses
2329  *                     on the association are effected.
2330  *
2331  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2332  *                     discovery upon the specified address. Note that
2333  *                     if the address feild is empty then all addresses
2334  *                     on the association are effected. Not also that
2335  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2336  *                     exclusive. Enabling both will have undetermined
2337  *                     results.
2338  *
2339  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2340  *                     on delayed sack. The time specified in spp_sackdelay
2341  *                     is used to specify the sack delay for this address. Note
2342  *                     that if spp_address is empty then all addresses will
2343  *                     enable delayed sack and take on the sack delay
2344  *                     value specified in spp_sackdelay.
2345  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2346  *                     off delayed sack. If the spp_address field is blank then
2347  *                     delayed sack is disabled for the entire association. Note
2348  *                     also that this field is mutually exclusive to
2349  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2350  *                     results.
2351  */
2352 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2353                                        struct sctp_transport   *trans,
2354                                        struct sctp_association *asoc,
2355                                        struct sctp_sock        *sp,
2356                                        int                      hb_change,
2357                                        int                      pmtud_change,
2358                                        int                      sackdelay_change)
2359 {
2360         int error;
2361 
2362         if (params->spp_flags & SPP_HB_DEMAND && trans) {
2363                 struct net *net = sock_net(trans->asoc->base.sk);
2364 
2365                 error = sctp_primitive_REQUESTHEARTBEAT(net, trans->asoc, trans);
2366                 if (error)
2367                         return error;
2368         }
2369 
2370         /* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2371          * this field is ignored.  Note also that a value of zero indicates
2372          * the current setting should be left unchanged.
2373          */
2374         if (params->spp_flags & SPP_HB_ENABLE) {
2375 
2376                 /* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2377                  * set.  This lets us use 0 value when this flag
2378                  * is set.
2379                  */
2380                 if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2381                         params->spp_hbinterval = 0;
2382 
2383                 if (params->spp_hbinterval ||
2384                     (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2385                         if (trans) {
2386                                 trans->hbinterval =
2387                                     msecs_to_jiffies(params->spp_hbinterval);
2388                         } else if (asoc) {
2389                                 asoc->hbinterval =
2390                                     msecs_to_jiffies(params->spp_hbinterval);
2391                         } else {
2392                                 sp->hbinterval = params->spp_hbinterval;
2393                         }
2394                 }
2395         }
2396 
2397         if (hb_change) {
2398                 if (trans) {
2399                         trans->param_flags =
2400                                 (trans->param_flags & ~SPP_HB) | hb_change;
2401                 } else if (asoc) {
2402                         asoc->param_flags =
2403                                 (asoc->param_flags & ~SPP_HB) | hb_change;
2404                 } else {
2405                         sp->param_flags =
2406                                 (sp->param_flags & ~SPP_HB) | hb_change;
2407                 }
2408         }
2409 
2410         /* When Path MTU discovery is disabled the value specified here will
2411          * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2412          * include the flag SPP_PMTUD_DISABLE for this field to have any
2413          * effect).
2414          */
2415         if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2416                 if (trans) {
2417                         trans->pathmtu = params->spp_pathmtu;
2418                         sctp_assoc_sync_pmtu(sctp_opt2sk(sp), asoc);
2419                 } else if (asoc) {
2420                         asoc->pathmtu = params->spp_pathmtu;
2421                         sctp_frag_point(asoc, params->spp_pathmtu);
2422                 } else {
2423                         sp->pathmtu = params->spp_pathmtu;
2424                 }
2425         }
2426 
2427         if (pmtud_change) {
2428                 if (trans) {
2429                         int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2430                                 (params->spp_flags & SPP_PMTUD_ENABLE);
2431                         trans->param_flags =
2432                                 (trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2433                         if (update) {
2434                                 sctp_transport_pmtu(trans, sctp_opt2sk(sp));
2435                                 sctp_assoc_sync_pmtu(sctp_opt2sk(sp), asoc);
2436                         }
2437                 } else if (asoc) {
2438                         asoc->param_flags =
2439                                 (asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2440                 } else {
2441                         sp->param_flags =
2442                                 (sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2443                 }
2444         }
2445 
2446         /* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2447          * value of this field is ignored.  Note also that a value of zero
2448          * indicates the current setting should be left unchanged.
2449          */
2450         if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2451                 if (trans) {
2452                         trans->sackdelay =
2453                                 msecs_to_jiffies(params->spp_sackdelay);
2454                 } else if (asoc) {
2455                         asoc->sackdelay =
2456                                 msecs_to_jiffies(params->spp_sackdelay);
2457                 } else {
2458                         sp->sackdelay = params->spp_sackdelay;
2459                 }
2460         }
2461 
2462         if (sackdelay_change) {
2463                 if (trans) {
2464                         trans->param_flags =
2465                                 (trans->param_flags & ~SPP_SACKDELAY) |
2466                                 sackdelay_change;
2467                 } else if (asoc) {
2468                         asoc->param_flags =
2469                                 (asoc->param_flags & ~SPP_SACKDELAY) |
2470                                 sackdelay_change;
2471                 } else {
2472                         sp->param_flags =
2473                                 (sp->param_flags & ~SPP_SACKDELAY) |
2474                                 sackdelay_change;
2475                 }
2476         }
2477 
2478         /* Note that a value of zero indicates the current setting should be
2479            left unchanged.
2480          */
2481         if (params->spp_pathmaxrxt) {
2482                 if (trans) {
2483                         trans->pathmaxrxt = params->spp_pathmaxrxt;
2484                 } else if (asoc) {
2485                         asoc->pathmaxrxt = params->spp_pathmaxrxt;
2486                 } else {
2487                         sp->pathmaxrxt = params->spp_pathmaxrxt;
2488                 }
2489         }
2490 
2491         return 0;
2492 }
2493 
2494 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2495                                             char __user *optval,
2496                                             unsigned int optlen)
2497 {
2498         struct sctp_paddrparams  params;
2499         struct sctp_transport   *trans = NULL;
2500         struct sctp_association *asoc = NULL;
2501         struct sctp_sock        *sp = sctp_sk(sk);
2502         int error;
2503         int hb_change, pmtud_change, sackdelay_change;
2504 
2505         if (optlen != sizeof(struct sctp_paddrparams))
2506                 return -EINVAL;
2507 
2508         if (copy_from_user(&params, optval, optlen))
2509                 return -EFAULT;
2510 
2511         /* Validate flags and value parameters. */
2512         hb_change        = params.spp_flags & SPP_HB;
2513         pmtud_change     = params.spp_flags & SPP_PMTUD;
2514         sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2515 
2516         if (hb_change        == SPP_HB ||
2517             pmtud_change     == SPP_PMTUD ||
2518             sackdelay_change == SPP_SACKDELAY ||
2519             params.spp_sackdelay > 500 ||
2520             (params.spp_pathmtu &&
2521              params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2522                 return -EINVAL;
2523 
2524         /* If an address other than INADDR_ANY is specified, and
2525          * no transport is found, then the request is invalid.
2526          */
2527         if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
2528                 trans = sctp_addr_id2transport(sk, &params.spp_address,
2529                                                params.spp_assoc_id);
2530                 if (!trans)
2531                         return -EINVAL;
2532         }
2533 
2534         /* Get association, if assoc_id != 0 and the socket is a one
2535          * to many style socket, and an association was not found, then
2536          * the id was invalid.
2537          */
2538         asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2539         if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2540                 return -EINVAL;
2541 
2542         /* Heartbeat demand can only be sent on a transport or
2543          * association, but not a socket.
2544          */
2545         if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2546                 return -EINVAL;
2547 
2548         /* Process parameters. */
2549         error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2550                                             hb_change, pmtud_change,
2551                                             sackdelay_change);
2552 
2553         if (error)
2554                 return error;
2555 
2556         /* If changes are for association, also apply parameters to each
2557          * transport.
2558          */
2559         if (!trans && asoc) {
2560                 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2561                                 transports) {
2562                         sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2563                                                     hb_change, pmtud_change,
2564                                                     sackdelay_change);
2565                 }
2566         }
2567 
2568         return 0;
2569 }
2570 
2571 static inline __u32 sctp_spp_sackdelay_enable(__u32 param_flags)
2572 {
2573         return (param_flags & ~SPP_SACKDELAY) | SPP_SACKDELAY_ENABLE;
2574 }
2575 
2576 static inline __u32 sctp_spp_sackdelay_disable(__u32 param_flags)
2577 {
2578         return (param_flags & ~SPP_SACKDELAY) | SPP_SACKDELAY_DISABLE;
2579 }
2580 
2581 /*
2582  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
2583  *
2584  * This option will effect the way delayed acks are performed.  This
2585  * option allows you to get or set the delayed ack time, in
2586  * milliseconds.  It also allows changing the delayed ack frequency.
2587  * Changing the frequency to 1 disables the delayed sack algorithm.  If
2588  * the assoc_id is 0, then this sets or gets the endpoints default
2589  * values.  If the assoc_id field is non-zero, then the set or get
2590  * effects the specified association for the one to many model (the
2591  * assoc_id field is ignored by the one to one model).  Note that if
2592  * sack_delay or sack_freq are 0 when setting this option, then the
2593  * current values will remain unchanged.
2594  *
2595  * struct sctp_sack_info {
2596  *     sctp_assoc_t            sack_assoc_id;
2597  *     uint32_t                sack_delay;
2598  *     uint32_t                sack_freq;
2599  * };
2600  *
2601  * sack_assoc_id -  This parameter, indicates which association the user
2602  *    is performing an action upon.  Note that if this field's value is
2603  *    zero then the endpoints default value is changed (effecting future
2604  *    associations only).
2605  *
2606  * sack_delay -  This parameter contains the number of milliseconds that
2607  *    the user is requesting the delayed ACK timer be set to.  Note that
2608  *    this value is defined in the standard to be between 200 and 500
2609  *    milliseconds.
2610  *
2611  * sack_freq -  This parameter contains the number of packets that must
2612  *    be received before a sack is sent without waiting for the delay
2613  *    timer to expire.  The default value for this is 2, setting this
2614  *    value to 1 will disable the delayed sack algorithm.
2615  */
2616 
2617 static int sctp_setsockopt_delayed_ack(struct sock *sk,
2618                                        char __user *optval, unsigned int optlen)
2619 {
2620         struct sctp_sack_info    params;
2621         struct sctp_transport   *trans = NULL;
2622         struct sctp_association *asoc = NULL;
2623         struct sctp_sock        *sp = sctp_sk(sk);
2624 
2625         if (optlen == sizeof(struct sctp_sack_info)) {
2626                 if (copy_from_user(&params, optval, optlen))
2627                         return -EFAULT;
2628 
2629                 if (params.sack_delay == 0 && params.sack_freq == 0)
2630                         return 0;
2631         } else if (optlen == sizeof(struct sctp_assoc_value)) {
2632                 pr_warn_ratelimited(DEPRECATED
2633                                     "%s (pid %d) "
2634                                     "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
2635                                     "Use struct sctp_sack_info instead\n",
2636                                     current->comm, task_pid_nr(current));
2637                 if (copy_from_user(&params, optval, optlen))
2638                         return -EFAULT;
2639 
2640                 if (params.sack_delay == 0)
2641                         params.sack_freq = 1;
2642                 else
2643                         params.sack_freq = 0;
2644         } else
2645                 return -EINVAL;
2646 
2647         /* Validate value parameter. */
2648         if (params.sack_delay > 500)
2649                 return -EINVAL;
2650 
2651         /* Get association, if sack_assoc_id != 0 and the socket is a one
2652          * to many style socket, and an association was not found, then
2653          * the id was invalid.
2654          */
2655         asoc = sctp_id2assoc(sk, params.sack_assoc_id);
2656         if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
2657                 return -EINVAL;
2658 
2659         if (params.sack_delay) {
2660                 if (asoc) {
2661                         asoc->sackdelay =
2662                                 msecs_to_jiffies(params.sack_delay);
2663                         asoc->param_flags =
2664                                 sctp_spp_sackdelay_enable(asoc->param_flags);
2665                 } else {
2666                         sp->sackdelay = params.sack_delay;
2667                         sp->param_flags =
2668                                 sctp_spp_sackdelay_enable(sp->param_flags);
2669                 }
2670         }
2671 
2672         if (params.sack_freq == 1) {
2673                 if (asoc) {
2674                         asoc->param_flags =
2675                                 sctp_spp_sackdelay_disable(asoc->param_flags);
2676                 } else {
2677                         sp->param_flags =
2678                                 sctp_spp_sackdelay_disable(sp->param_flags);
2679                 }
2680         } else if (params.sack_freq > 1) {
2681                 if (asoc) {
2682                         asoc->sackfreq = params.sack_freq;
2683                         asoc->param_flags =
2684                                 sctp_spp_sackdelay_enable(asoc->param_flags);
2685                 } else {
2686                         sp->sackfreq = params.sack_freq;
2687                         sp->param_flags =
2688                                 sctp_spp_sackdelay_enable(sp->param_flags);
2689                 }
2690         }
2691 
2692         /* If change is for association, also apply to each transport. */
2693         if (asoc) {
2694                 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2695                                 transports) {
2696                         if (params.sack_delay) {
2697                                 trans->sackdelay =
2698                                         msecs_to_jiffies(params.sack_delay);
2699                                 trans->param_flags =
2700                                         sctp_spp_sackdelay_enable(trans->param_flags);
2701                         }
2702                         if (params.sack_freq == 1) {
2703                                 trans->param_flags =
2704                                         sctp_spp_sackdelay_disable(trans->param_flags);
2705                         } else if (params.sack_freq > 1) {
2706                                 trans->sackfreq = params.sack_freq;
2707                                 trans->param_flags =
2708                                         sctp_spp_sackdelay_enable(trans->param_flags);
2709                         }
2710                 }
2711         }
2712 
2713         return 0;
2714 }
2715 
2716 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2717  *
2718  * Applications can specify protocol parameters for the default association
2719  * initialization.  The option name argument to setsockopt() and getsockopt()
2720  * is SCTP_INITMSG.
2721  *
2722  * Setting initialization parameters is effective only on an unconnected
2723  * socket (for UDP-style sockets only future associations are effected
2724  * by the change).  With TCP-style sockets, this option is inherited by
2725  * sockets derived from a listener socket.
2726  */
2727 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, unsigned int optlen)
2728 {
2729         struct sctp_initmsg sinit;
2730         struct sctp_sock *sp = sctp_sk(sk);
2731 
2732         if (optlen != sizeof(struct sctp_initmsg))
2733                 return -EINVAL;
2734         if (copy_from_user(&sinit, optval, optlen))
2735                 return -EFAULT;
2736 
2737         if (sinit.sinit_num_ostreams)
2738                 sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2739         if (sinit.sinit_max_instreams)
2740                 sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2741         if (sinit.sinit_max_attempts)
2742                 sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2743         if (sinit.sinit_max_init_timeo)
2744                 sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2745 
2746         return 0;
2747 }
2748 
2749 /*
2750  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2751  *
2752  *   Applications that wish to use the sendto() system call may wish to
2753  *   specify a default set of parameters that would normally be supplied
2754  *   through the inclusion of ancillary data.  This socket option allows
2755  *   such an application to set the default sctp_sndrcvinfo structure.
2756  *   The application that wishes to use this socket option simply passes
2757  *   in to this call the sctp_sndrcvinfo structure defined in Section
2758  *   5.2.2) The input parameters accepted by this call include
2759  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2760  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2761  *   to this call if the caller is using the UDP model.
2762  */
2763 static int sctp_setsockopt_default_send_param(struct sock *sk,
2764                                               char __user *optval,
2765                                               unsigned int optlen)
2766 {
2767         struct sctp_sock *sp = sctp_sk(sk);
2768         struct sctp_association *asoc;
2769         struct sctp_sndrcvinfo info;
2770 
2771         if (optlen != sizeof(info))
2772                 return -EINVAL;
2773         if (copy_from_user(&info, optval, optlen))
2774                 return -EFAULT;
2775         if (info.sinfo_flags &
2776             ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
2777               SCTP_ABORT | SCTP_EOF))
2778                 return -EINVAL;
2779 
2780         asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2781         if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2782                 return -EINVAL;
2783         if (asoc) {
2784                 asoc->default_stream = info.sinfo_stream;
2785                 asoc->default_flags = info.sinfo_flags;
2786                 asoc->default_ppid = info.sinfo_ppid;
2787                 asoc->default_context = info.sinfo_context;
2788                 asoc->default_timetolive = info.sinfo_timetolive;
2789         } else {
2790                 sp->default_stream = info.sinfo_stream;
2791                 sp->default_flags = info.sinfo_flags;
2792                 sp->default_ppid = info.sinfo_ppid;
2793                 sp->default_context = info.sinfo_context;
2794                 sp->default_timetolive = info.sinfo_timetolive;
2795         }
2796 
2797         return 0;
2798 }
2799 
2800 /* RFC6458, Section 8.1.31. Set/get Default Send Parameters
2801  * (SCTP_DEFAULT_SNDINFO)
2802  */
2803 static int sctp_setsockopt_default_sndinfo(struct sock *sk,
2804                                            char __user *optval,
2805                                            unsigned int optlen)
2806 {
2807         struct sctp_sock *sp = sctp_sk(sk);
2808         struct sctp_association *asoc;
2809         struct sctp_sndinfo info;
2810 
2811         if (optlen != sizeof(info))
2812                 return -EINVAL;
2813         if (copy_from_user(&info, optval, optlen))
2814                 return -EFAULT;
2815         if (info.snd_flags &
2816             ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
2817               SCTP_ABORT | SCTP_EOF))
2818                 return -EINVAL;
2819 
2820         asoc = sctp_id2assoc(sk, info.snd_assoc_id);
2821         if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
2822                 return -EINVAL;
2823         if (asoc) {
2824                 asoc->default_stream = info.snd_sid;
2825                 asoc->default_flags = info.snd_flags;
2826                 asoc->default_ppid = info.snd_ppid;
2827                 asoc->default_context = info.snd_context;
2828         } else {
2829                 sp->default_stream = info.snd_sid;
2830                 sp->default_flags = info.snd_flags;
2831                 sp->default_ppid = info.snd_ppid;
2832                 sp->default_context = info.snd_context;
2833         }
2834 
2835         return 0;
2836 }
2837 
2838 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2839  *
2840  * Requests that the local SCTP stack use the enclosed peer address as
2841  * the association primary.  The enclosed address must be one of the
2842  * association peer's addresses.
2843  */
2844 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2845                                         unsigned int optlen)
2846 {
2847         struct sctp_prim prim;
2848         struct sctp_transport *trans;
2849 
2850         if (optlen != sizeof(struct sctp_prim))
2851                 return -EINVAL;
2852 
2853         if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2854                 return -EFAULT;
2855 
2856         trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2857         if (!trans)
2858                 return -EINVAL;
2859 
2860         sctp_assoc_set_primary(trans->asoc, trans);
2861 
2862         return 0;
2863 }
2864 
2865 /*
2866  * 7.1.5 SCTP_NODELAY
2867  *
2868  * Turn on/off any Nagle-like algorithm.  This means that packets are
2869  * generally sent as soon as possible and no unnecessary delays are
2870  * introduced, at the cost of more packets in the network.  Expects an
2871  *  integer boolean flag.
2872  */
2873 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2874                                    unsigned int optlen)
2875 {
2876         int val;
2877 
2878         if (optlen < sizeof(int))
2879                 return -EINVAL;
2880         if (get_user(val, (int __user *)optval))
2881                 return -EFAULT;
2882 
2883         sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2884         return 0;
2885 }
2886 
2887 /*
2888  *
2889  * 7.1.1 SCTP_RTOINFO
2890  *
2891  * The protocol parameters used to initialize and bound retransmission
2892  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2893  * and modify these parameters.
2894  * All parameters are time values, in milliseconds.  A value of 0, when
2895  * modifying the parameters, indicates that the current value should not
2896  * be changed.
2897  *
2898  */
2899 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, unsigned int optlen)
2900 {
2901         struct sctp_rtoinfo rtoinfo;
2902         struct sctp_association *asoc;
2903         unsigned long rto_min, rto_max;
2904         struct sctp_sock *sp = sctp_sk(sk);
2905 
2906         if (optlen != sizeof (struct sctp_rtoinfo))
2907                 return -EINVAL;
2908 
2909         if (copy_from_user(&rtoinfo, optval, optlen))
2910                 return -EFAULT;
2911 
2912         asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2913 
2914         /* Set the values to the specific association */
2915         if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2916                 return -EINVAL;
2917 
2918         rto_max = rtoinfo.srto_max;
2919         rto_min = rtoinfo.srto_min;
2920 
2921         if (rto_max)
2922                 rto_max = asoc ? msecs_to_jiffies(rto_max) : rto_max;
2923         else
2924                 rto_max = asoc ? asoc->rto_max : sp->rtoinfo.srto_max;
2925 
2926         if (rto_min)
2927                 rto_min = asoc ? msecs_to_jiffies(rto_min) : rto_min;
2928         else
2929                 rto_min = asoc ? asoc->rto_min : sp->rtoinfo.srto_min;
2930 
2931         if (rto_min > rto_max)
2932                 return -EINVAL;
2933 
2934         if (asoc) {
2935                 if (rtoinfo.srto_initial != 0)
2936                         asoc->rto_initial =
2937                                 msecs_to_jiffies(rtoinfo.srto_initial);
2938                 asoc->rto_max = rto_max;
2939                 asoc->rto_min = rto_min;
2940         } else {
2941                 /* If there is no association or the association-id = 0
2942                  * set the values to the endpoint.
2943                  */
2944                 if (rtoinfo.srto_initial != 0)
2945                         sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2946                 sp->rtoinfo.srto_max = rto_max;
2947                 sp->rtoinfo.srto_min = rto_min;
2948         }
2949 
2950         return 0;
2951 }
2952 
2953 /*
2954  *
2955  * 7.1.2 SCTP_ASSOCINFO
2956  *
2957  * This option is used to tune the maximum retransmission attempts
2958  * of the association.
2959  * Returns an error if the new association retransmission value is
2960  * greater than the sum of the retransmission value  of the peer.
2961  * See [SCTP] for more information.
2962  *
2963  */
2964 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, unsigned int optlen)
2965 {
2966 
2967         struct sctp_assocparams assocparams;
2968         struct sctp_association *asoc;
2969 
2970         if (optlen != sizeof(struct sctp_assocparams))
2971                 return -EINVAL;
2972         if (copy_from_user(&assocparams, optval, optlen))
2973                 return -EFAULT;
2974 
2975         asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2976 
2977         if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2978                 return -EINVAL;
2979 
2980         /* Set the values to the specific association */
2981         if (asoc) {
2982                 if (assocparams.sasoc_asocmaxrxt != 0) {
2983                         __u32 path_sum = 0;
2984                         int   paths = 0;
2985                         struct sctp_transport *peer_addr;
2986 
2987                         list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
2988                                         transports) {
2989                                 path_sum += peer_addr->pathmaxrxt;
2990                                 paths++;
2991                         }
2992 
2993                         /* Only validate asocmaxrxt if we have more than
2994                          * one path/transport.  We do this because path
2995                          * retransmissions are only counted when we have more
2996                          * then one path.
2997                          */
2998                         if (paths > 1 &&
2999                             assocparams.sasoc_asocmaxrxt > path_sum)
3000                                 return -EINVAL;
3001 
3002                         asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
3003                 }
3004 
3005                 if (assocparams.sasoc_cookie_life != 0)
3006                         asoc->cookie_life = ms_to_ktime(assocparams.sasoc_cookie_life);
3007         } else {
3008                 /* Set the values to the endpoint */
3009                 struct sctp_sock *sp = sctp_sk(sk);
3010 
3011                 if (assocparams.sasoc_asocmaxrxt != 0)
3012                         sp->assocparams.sasoc_asocmaxrxt =
3013                                                 assocparams.sasoc_asocmaxrxt;
3014                 if (assocparams.sasoc_cookie_life != 0)
3015                         sp->assocparams.sasoc_cookie_life =
3016                                                 assocparams.sasoc_cookie_life;
3017         }
3018         return 0;
3019 }
3020 
3021 /*
3022  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
3023  *
3024  * This socket option is a boolean flag which turns on or off mapped V4
3025  * addresses.  If this option is turned on and the socket is type
3026  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
3027  * If this option is turned off, then no mapping will be done of V4
3028  * addresses and a user will receive both PF_INET6 and PF_INET type
3029  * addresses on the socket.
3030  */
3031 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsigned int optlen)
3032 {
3033         int val;
3034         struct sctp_sock *sp = sctp_sk(sk);
3035 
3036         if (optlen < sizeof(int))
3037                 return -EINVAL;
3038         if (get_user(val, (int __user *)optval))
3039                 return -EFAULT;
3040         if (val)
3041                 sp->v4mapped = 1;
3042         else
3043                 sp->v4mapped = 0;
3044 
3045         return 0;
3046 }
3047 
3048 /*
3049  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
3050  * This option will get or set the maximum size to put in any outgoing
3051  * SCTP DATA chunk.  If a message is larger than this size it will be
3052  * fragmented by SCTP into the specified size.  Note that the underlying
3053  * SCTP implementation may fragment into smaller sized chunks when the
3054  * PMTU of the underlying association is smaller than the value set by
3055  * the user.  The default value for this option is '' which indicates
3056  * the user is NOT limiting fragmentation and only the PMTU will effect
3057  * SCTP's choice of DATA chunk size.  Note also that values set larger
3058  * than the maximum size of an IP datagram will effectively let SCTP
3059  * control fragmentation (i.e. the same as setting this option to 0).
3060  *
3061  * The following structure is used to access and modify this parameter:
3062  *
3063  * struct sctp_assoc_value {
3064  *   sctp_assoc_t assoc_id;
3065  *   uint32_t assoc_value;
3066  * };
3067  *
3068  * assoc_id:  This parameter is ignored for one-to-one style sockets.
3069  *    For one-to-many style sockets this parameter indicates which
3070  *    association the user is performing an action upon.  Note that if
3071  *    this field's value is zero then the endpoints default value is
3072  *    changed (effecting future associations only).
3073  * assoc_value:  This parameter specifies the maximum size in bytes.
3074  */
3075 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
3076 {
3077         struct sctp_assoc_value params;
3078         struct sctp_association *asoc;
3079         struct sctp_sock *sp = sctp_sk(sk);
3080         int val;
3081 
3082         if (optlen == sizeof(int)) {
3083                 pr_warn_ratelimited(DEPRECATED
3084                                     "%s (pid %d) "
3085                                     "Use of int in maxseg socket option.\n"
3086                                     "Use struct sctp_assoc_value instead\n",
3087                                     current->comm, task_pid_nr(current));
3088                 if (copy_from_user(&val, optval, optlen))
3089                         return -EFAULT;
3090                 params.assoc_id = 0;
3091         } else if (optlen == sizeof(struct sctp_assoc_value)) {
3092                 if (copy_from_user(&params, optval, optlen))
3093                         return -EFAULT;
3094                 val = params.assoc_value;
3095         } else
3096                 return -EINVAL;
3097 
3098         if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
3099                 return -EINVAL;
3100 
3101         asoc = sctp_id2assoc(sk, params.assoc_id);
3102         if (!asoc && params.assoc_id && sctp_style(sk, UDP))
3103                 return -EINVAL;
3104 
3105         if (asoc) {
3106                 if (val == 0) {
3107                         val = asoc->pathmtu;
3108                         val -= sp->pf->af->net_header_len;
3109                         val -= sizeof(struct sctphdr) +
3110                                         sizeof(struct sctp_data_chunk);
3111                 }
3112                 asoc->user_frag = val;
3113                 asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
3114         } else {
3115                 sp->user_frag = val;
3116         }
3117 
3118         return 0;
3119 }
3120 
3121 
3122 /*
3123  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
3124  *
3125  *   Requests that the peer mark the enclosed address as the association
3126  *   primary. The enclosed address must be one of the association's
3127  *   locally bound addresses. The following structure is used to make a
3128  *   set primary request:
3129  */
3130 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
3131                                              unsigned int optlen)
3132 {
3133         struct net *net = sock_net(sk);
3134         struct sctp_sock        *sp;
3135         struct sctp_association *asoc = NULL;
3136         struct sctp_setpeerprim prim;
3137         struct sctp_chunk       *chunk;
3138         struct sctp_af          *af;
3139         int                     err;
3140 
3141         sp = sctp_sk(sk);
3142 
3143         if (!net->sctp.addip_enable)
3144                 return -EPERM;
3145 
3146         if (optlen != sizeof(struct sctp_setpeerprim))
3147                 return -EINVAL;
3148 
3149         if (copy_from_user(&prim, optval, optlen))
3150                 return -EFAULT;
3151 
3152         asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
3153         if (!asoc)
3154                 return -EINVAL;
3155 
3156         if (!asoc->peer.asconf_capable)
3157                 return -EPERM;
3158 
3159         if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
3160                 return -EPERM;
3161 
3162         if (!sctp_state(asoc, ESTABLISHED))
3163                 return -ENOTCONN;
3164 
3165         af = sctp_get_af_specific(prim.sspp_addr.ss_family);
3166         if (!af)
3167                 return -EINVAL;
3168 
3169         if (!af->addr_valid((union sctp_addr *)&prim.sspp_addr, sp, NULL))
3170                 return -EADDRNOTAVAIL;
3171 
3172         if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
3173                 return -EADDRNOTAVAIL;
3174 
3175         /* Create an ASCONF chunk with SET_PRIMARY parameter    */
3176         chunk = sctp_make_asconf_set_prim(asoc,
3177                                           (union sctp_addr *)&prim.sspp_addr);
3178         if (!chunk)
3179                 return -ENOMEM;
3180 
3181         err = sctp_send_asconf(asoc, chunk);
3182 
3183         pr_debug("%s: we set peer primary addr primitively\n", __func__);
3184 
3185         return err;
3186 }
3187 
3188 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
3189                                             unsigned int optlen)
3190 {
3191         struct sctp_setadaptation adaptation;
3192 
3193         if (optlen != sizeof(struct sctp_setadaptation))
3194                 return -EINVAL;
3195         if (copy_from_user(&adaptation, optval, optlen))
3196                 return -EFAULT;
3197 
3198         sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
3199 
3200         return 0;
3201 }
3202 
3203 /*
3204  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
3205  *
3206  * The context field in the sctp_sndrcvinfo structure is normally only
3207  * used when a failed message is retrieved holding the value that was
3208  * sent down on the actual send call.  This option allows the setting of
3209  * a default context on an association basis that will be received on
3210  * reading messages from the peer.  This is especially helpful in the
3211  * one-2-many model for an application to keep some reference to an
3212  * internal state machine that is processing messages on the
3213  * association.  Note that the setting of this value only effects
3214  * received messages from the peer and does not effect the value that is
3215  * saved with outbound messages.
3216  */
3217 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
3218                                    unsigned int optlen)
3219 {
3220         struct sctp_assoc_value params;
3221         struct sctp_sock *sp;
3222         struct sctp_association *asoc;
3223 
3224         if (optlen != sizeof(struct sctp_assoc_value))
3225                 return -EINVAL;
3226         if (copy_from_user(&params, optval, optlen))
3227                 return -EFAULT;
3228 
3229         sp = sctp_sk(sk);
3230 
3231         if (params.assoc_id != 0) {
3232                 asoc = sctp_id2assoc(sk, params.assoc_id);
3233                 if (!asoc)
3234                         return -EINVAL;
3235                 asoc->default_rcv_context = params.assoc_value;
3236         } else {
3237                 sp->default_rcv_context = params.assoc_value;
3238         }
3239 
3240         return 0;
3241 }
3242 
3243 /*
3244  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
3245  *
3246  * This options will at a minimum specify if the implementation is doing
3247  * fragmented interleave.  Fragmented interleave, for a one to many
3248  * socket, is when subsequent calls to receive a message may return
3249  * parts of messages from different associations.  Some implementations
3250  * may allow you to turn this value on or off.  If so, when turned off,
3251  * no fragment interleave will occur (which will cause a head of line
3252  * blocking amongst multiple associations sharing the same one to many
3253  * socket).  When this option is turned on, then each receive call may
3254  * come from a different association (thus the user must receive data
3255  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
3256  * association each receive belongs to.
3257  *
3258  * This option takes a boolean value.  A non-zero value indicates that
3259  * fragmented interleave is on.  A value of zero indicates that
3260  * fragmented interleave is off.
3261  *
3262  * Note that it is important that an implementation that allows this
3263  * option to be turned on, have it off by default.  Otherwise an unaware
3264  * application using the one to many model may become confused and act
3265  * incorrectly.
3266  */
3267 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
3268                                                char __user *optval,
3269                                                unsigned int optlen)
3270 {
3271         int val;
3272 
3273         if (optlen != sizeof(int))
3274                 return -EINVAL;
3275         if (get_user(val, (int __user *)optval))
3276                 return -EFAULT;
3277 
3278         sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
3279 
3280         return 0;
3281 }
3282 
3283 /*
3284  * 8.1.21.  Set or Get the SCTP Partial Delivery Point
3285  *       (SCTP_PARTIAL_DELIVERY_POINT)
3286  *
3287  * This option will set or get the SCTP partial delivery point.  This
3288  * point is the size of a message where the partial delivery API will be
3289  * invoked to help free up rwnd space for the peer.  Setting this to a
3290  * lower value will cause partial deliveries to happen more often.  The
3291  * calls argument is an integer that sets or gets the partial delivery
3292  * point.  Note also that the call will fail if the user attempts to set
3293  * this value larger than the socket receive buffer size.
3294  *
3295  * Note that any single message having a length smaller than or equal to
3296  * the SCTP partial delivery point will be delivered in one single read
3297  * call as long as the user provided buffer is large enough to hold the
3298  * message.
3299  */
3300 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
3301                                                   char __user *optval,
3302                                                   unsigned int optlen)
3303 {
3304         u32 val;
3305 
3306         if (optlen != sizeof(u32))
3307                 return -EINVAL;
3308         if (get_user(val, (int __user *)optval))
3309                 return -EFAULT;
3310 
3311         /* Note: We double the receive buffer from what the user sets
3312          * it to be, also initial rwnd is based on rcvbuf/2.
3313          */
3314         if (val > (sk->sk_rcvbuf >> 1))
3315                 return -EINVAL;
3316 
3317         sctp_sk(sk)->pd_point = val;
3318 
3319         return 0; /* is this the right error code? */
3320 }
3321 
3322 /*
3323  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
3324  *
3325  * This option will allow a user to change the maximum burst of packets
3326  * that can be emitted by this association.  Note that the default value
3327  * is 4, and some implementations may restrict this setting so that it
3328  * can only be lowered.
3329  *
3330  * NOTE: This text doesn't seem right.  Do this on a socket basis with
3331  * future associations inheriting the socket value.
3332  */
3333 static int sctp_setsockopt_maxburst(struct sock *sk,
3334                                     char __user *optval,
3335                                     unsigned int optlen)
3336 {
3337         struct sctp_assoc_value params;
3338         struct sctp_sock *sp;
3339         struct sctp_association *asoc;
3340         int val;
3341         int assoc_id = 0;
3342 
3343         if (optlen == sizeof(int)) {
3344                 pr_warn_ratelimited(DEPRECATED
3345                                     "%s (pid %d) "
3346                                     "Use of int in max_burst socket option deprecated.\n"
3347                                     "Use struct sctp_assoc_value instead\n",
3348                                     current->comm, task_pid_nr(current));
3349                 if (copy_from_user(&val, optval, optlen))
3350                         return -EFAULT;
3351         } else if (optlen == sizeof(struct sctp_assoc_value)) {
3352                 if (copy_from_user(&params, optval, optlen))
3353                         return -EFAULT;
3354                 val = params.assoc_value;
3355                 assoc_id = params.assoc_id;
3356         } else
3357                 return -EINVAL;
3358 
3359         sp = sctp_sk(sk);
3360 
3361         if (assoc_id != 0) {
3362                 asoc = sctp_id2assoc(sk, assoc_id);
3363                 if (!asoc)
3364                         return -EINVAL;
3365                 asoc->max_burst = val;
3366         } else
3367                 sp->max_burst = val;
3368 
3369         return 0;
3370 }
3371 
3372 /*
3373  * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
3374  *
3375  * This set option adds a chunk type that the user is requesting to be
3376  * received only in an authenticated way.  Changes to the list of chunks
3377  * will only effect future associations on the socket.
3378  */
3379 static int sctp_setsockopt_auth_chunk(struct sock *sk,
3380                                       char __user *optval,
3381                                       unsigned int optlen)
3382 {
3383         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3384         struct sctp_authchunk val;
3385 
3386         if (!ep->auth_enable)
3387                 return -EACCES;
3388 
3389         if (optlen != sizeof(struct sctp_authchunk))
3390                 return -EINVAL;
3391         if (copy_from_user(&val, optval, optlen))
3392                 return -EFAULT;
3393 
3394         switch (val.sauth_chunk) {
3395         case SCTP_CID_INIT:
3396         case SCTP_CID_INIT_ACK:
3397         case SCTP_CID_SHUTDOWN_COMPLETE:
3398         case SCTP_CID_AUTH:
3399                 return -EINVAL;
3400         }
3401 
3402         /* add this chunk id to the endpoint */
3403         return sctp_auth_ep_add_chunkid(ep, val.sauth_chunk);
3404 }
3405 
3406 /*
3407  * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
3408  *
3409  * This option gets or sets the list of HMAC algorithms that the local
3410  * endpoint requires the peer to use.
3411  */
3412 static int sctp_setsockopt_hmac_ident(struct sock *sk,
3413                                       char __user *optval,
3414                                       unsigned int optlen)
3415 {
3416         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3417         struct sctp_hmacalgo *hmacs;
3418         u32 idents;
3419         int err;
3420 
3421         if (!ep->auth_enable)
3422                 return -EACCES;
3423 
3424         if (optlen < sizeof(struct sctp_hmacalgo))
3425                 return -EINVAL;
3426 
3427         hmacs = memdup_user(optval, optlen);
3428         if (IS_ERR(hmacs))
3429                 return PTR_ERR(hmacs);
3430 
3431         idents = hmacs->shmac_num_idents;
3432         if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
3433             (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) {
3434                 err = -EINVAL;
3435                 goto out;
3436         }
3437 
3438         err = sctp_auth_ep_set_hmacs(ep, hmacs);
3439 out:
3440         kfree(hmacs);
3441         return err;
3442 }
3443 
3444 /*
3445  * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
3446  *
3447  * This option will set a shared secret key which is used to build an
3448  * association shared key.
3449  */
3450 static int sctp_setsockopt_auth_key(struct sock *sk,
3451                                     char __user *optval,
3452                                     unsigned int optlen)
3453 {
3454         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3455         struct sctp_authkey *authkey;
3456         struct sctp_association *asoc;
3457         int ret;
3458 
3459         if (!ep->auth_enable)
3460                 return -EACCES;
3461 
3462         if (optlen <= sizeof(struct sctp_authkey))
3463                 return -EINVAL;
3464 
3465         authkey = memdup_user(optval, optlen);
3466         if (IS_ERR(authkey))
3467                 return PTR_ERR(authkey);
3468 
3469         if (authkey->sca_keylength > optlen - sizeof(struct sctp_authkey)) {
3470                 ret = -EINVAL;
3471                 goto out;
3472         }
3473 
3474         asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
3475         if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
3476                 ret = -EINVAL;
3477                 goto out;
3478         }
3479 
3480         ret = sctp_auth_set_key(ep, asoc, authkey);
3481 out:
3482         kzfree(authkey);
3483         return ret;
3484 }
3485 
3486 /*
3487  * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
3488  *
3489  * This option will get or set the active shared key to be used to build
3490  * the association shared key.
3491  */
3492 static int sctp_setsockopt_active_key(struct sock *sk,
3493                                       char __user *optval,
3494                                       unsigned int optlen)
3495 {
3496         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3497         struct sctp_authkeyid val;
3498         struct sctp_association *asoc;
3499 
3500         if (!ep->auth_enable)
3501                 return -EACCES;
3502 
3503         if (optlen != sizeof(struct sctp_authkeyid))
3504                 return -EINVAL;
3505         if (copy_from_user(&val, optval, optlen))
3506                 return -EFAULT;
3507 
3508         asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3509         if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3510                 return -EINVAL;
3511 
3512         return sctp_auth_set_active_key(ep, asoc, val.scact_keynumber);
3513 }
3514 
3515 /*
3516  * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
3517  *
3518  * This set option will delete a shared secret key from use.
3519  */
3520 static int sctp_setsockopt_del_key(struct sock *sk,
3521                                    char __user *optval,
3522                                    unsigned int optlen)
3523 {
3524         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3525         struct sctp_authkeyid val;
3526         struct sctp_association *asoc;
3527 
3528         if (!ep->auth_enable)
3529                 return -EACCES;
3530 
3531         if (optlen != sizeof(struct sctp_authkeyid))
3532                 return -EINVAL;
3533         if (copy_from_user(&val, optval, optlen))
3534                 return -EFAULT;
3535 
3536         asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3537         if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3538                 return -EINVAL;
3539 
3540         return sctp_auth_del_key_id(ep, asoc, val.scact_keynumber);
3541 
3542 }
3543 
3544 /*
3545  * 8.1.23 SCTP_AUTO_ASCONF
3546  *
3547  * This option will enable or disable the use of the automatic generation of
3548  * ASCONF chunks to add and delete addresses to an existing association.  Note
3549  * that this option has two caveats namely: a) it only affects sockets that
3550  * are bound to all addresses available to the SCTP stack, and b) the system
3551  * administrator may have an overriding control that turns the ASCONF feature
3552  * off no matter what setting the socket option may have.
3553  * This option expects an integer boolean flag, where a non-zero value turns on
3554  * the option, and a zero value turns off the option.
3555  * Note. In this implementation, socket operation overrides default parameter
3556  * being set by sysctl as well as FreeBSD implementation
3557  */
3558 static int sctp_setsockopt_auto_asconf(struct sock *sk, char __user *optval,
3559                                         unsigned int optlen)
3560 {
3561         int val;
3562         struct sctp_sock *sp = sctp_sk(sk);
3563 
3564         if (optlen < sizeof(int))
3565                 return -EINVAL;
3566         if (get_user(val, (int __user *)optval))
3567                 return -EFAULT;
3568         if (!sctp_is_ep_boundall(sk) && val)
3569                 return -EINVAL;
3570         if ((val && sp->do_auto_asconf) || (!val && !sp->do_auto_asconf))
3571                 return 0;
3572 
3573         spin_lock_bh(&sock_net(sk)->sctp.addr_wq_lock);
3574         if (val == 0 && sp->do_auto_asconf) {
3575                 list_del(&sp->auto_asconf_list);
3576                 sp->do_auto_asconf = 0;
3577         } else if (val && !sp->do_auto_asconf) {
3578                 list_add_tail(&sp->auto_asconf_list,
3579                     &sock_net(sk)->sctp.auto_asconf_splist);
3580                 sp->do_auto_asconf = 1;
3581         }
3582         spin_unlock_bh(&sock_net(sk)->sctp.addr_wq_lock);
3583         return 0;
3584 }
3585 
3586 /*
3587  * SCTP_PEER_ADDR_THLDS
3588  *
3589  * This option allows us to alter the partially failed threshold for one or all
3590  * transports in an association.  See Section 6.1 of:
3591  * http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt
3592  */
3593 static int sctp_setsockopt_paddr_thresholds(struct sock *sk,
3594                                             char __user *optval,
3595                                             unsigned int optlen)
3596 {
3597         struct sctp_paddrthlds val;
3598         struct sctp_transport *trans;
3599         struct sctp_association *asoc;
3600 
3601         if (optlen < sizeof(struct sctp_paddrthlds))
3602                 return -EINVAL;
3603         if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval,
3604                            sizeof(struct sctp_paddrthlds)))
3605                 return -EFAULT;
3606 
3607 
3608         if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
3609                 asoc = sctp_id2assoc(sk, val.spt_assoc_id);
3610                 if (!asoc)
3611                         return -ENOENT;
3612                 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
3613                                     transports) {
3614                         if (val.spt_pathmaxrxt)
3615                                 trans->pathmaxrxt = val.spt_pathmaxrxt;
3616                         trans->pf_retrans = val.spt_pathpfthld;
3617                 }
3618 
3619                 if (val.spt_pathmaxrxt)
3620                         asoc->pathmaxrxt = val.spt_pathmaxrxt;
3621                 asoc->pf_retrans = val.spt_pathpfthld;
3622         } else {
3623                 trans = sctp_addr_id2transport(sk, &val.spt_address,
3624                                                val.spt_assoc_id);
3625                 if (!trans)
3626                         return -ENOENT;
3627 
3628                 if (val.spt_pathmaxrxt)
3629                         trans->pathmaxrxt = val.spt_pathmaxrxt;
3630                 trans->pf_retrans = val.spt_pathpfthld;
3631         }
3632 
3633         return 0;
3634 }
3635 
3636 static int sctp_setsockopt_recvrcvinfo(struct sock *sk,
3637                                        char __user *optval,
3638                                        unsigned int optlen)
3639 {
3640         int val;
3641 
3642         if (optlen < sizeof(int))
3643                 return -EINVAL;
3644         if (get_user(val, (int __user *) optval))
3645                 return -EFAULT;
3646 
3647         sctp_sk(sk)->recvrcvinfo = (val == 0) ? 0 : 1;
3648 
3649         return 0;
3650 }
3651 
3652 static int sctp_setsockopt_recvnxtinfo(struct sock *sk,
3653                                        char __user *optval,
3654                                        unsigned int optlen)
3655 {
3656         int val;
3657 
3658         if (optlen < sizeof(int))
3659                 return -EINVAL;
3660         if (get_user(val, (int __user *) optval))
3661                 return -EFAULT;
3662 
3663         sctp_sk(sk)->recvnxtinfo = (val == 0) ? 0 : 1;
3664 
3665         return 0;
3666 }
3667 
3668 /* API 6.2 setsockopt(), getsockopt()
3669  *
3670  * Applications use setsockopt() and getsockopt() to set or retrieve
3671  * socket options.  Socket options are used to change the default
3672  * behavior of sockets calls.  They are described in Section 7.
3673  *
3674  * The syntax is:
3675  *
3676  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
3677  *                    int __user *optlen);
3678  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
3679  *                    int optlen);
3680  *
3681  *   sd      - the socket descript.
3682  *   level   - set to IPPROTO_SCTP for all SCTP options.
3683  *   optname - the option name.
3684  *   optval  - the buffer to store the value of the option.
3685  *   optlen  - the size of the buffer.
3686  */
3687 static int sctp_setsockopt(struct sock *sk, int level, int optname,
3688                            char __user *optval, unsigned int optlen)
3689 {
3690         int retval = 0;
3691 
3692         pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname);
3693 
3694         /* I can hardly begin to describe how wrong this is.  This is
3695          * so broken as to be worse than useless.  The API draft
3696          * REALLY is NOT helpful here...  I am not convinced that the
3697          * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
3698          * are at all well-founded.
3699          */
3700         if (level != SOL_SCTP) {
3701                 struct sctp_af *af = sctp_sk(sk)->pf->af;
3702                 retval = af->setsockopt(sk, level, optname, optval, optlen);
3703                 goto out_nounlock;
3704         }
3705 
3706         lock_sock(sk);
3707 
3708         switch (optname) {
3709         case SCTP_SOCKOPT_BINDX_ADD:
3710                 /* 'optlen' is the size of the addresses buffer. */
3711                 retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3712                                                optlen, SCTP_BINDX_ADD_ADDR);
3713                 break;
3714 
3715         case SCTP_SOCKOPT_BINDX_REM:
3716                 /* 'optlen' is the size of the addresses buffer. */
3717                 retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3718                                                optlen, SCTP_BINDX_REM_ADDR);
3719                 break;
3720 
3721         case SCTP_SOCKOPT_CONNECTX_OLD:
3722                 /* 'optlen' is the size of the addresses buffer. */
3723                 retval = sctp_setsockopt_connectx_old(sk,
3724                                             (struct sockaddr __user *)optval,
3725                                             optlen);
3726                 break;
3727 
3728         case SCTP_SOCKOPT_CONNECTX:
3729                 /* 'optlen' is the size of the addresses buffer. */
3730                 retval = sctp_setsockopt_connectx(sk,
3731                                             (struct sockaddr __user *)optval,
3732                                             optlen);
3733                 break;
3734 
3735         case SCTP_DISABLE_FRAGMENTS:
3736                 retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
3737                 break;
3738 
3739         case SCTP_EVENTS:
3740                 retval = sctp_setsockopt_events(sk, optval, optlen);
3741                 break;
3742 
3743         case SCTP_AUTOCLOSE:
3744                 retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3745                 break;
3746 
3747         case SCTP_PEER_ADDR_PARAMS:
3748                 retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3749                 break;
3750 
3751         case SCTP_DELAYED_SACK:
3752                 retval = sctp_setsockopt_delayed_ack(sk, optval, optlen);
3753                 break;
3754         case SCTP_PARTIAL_DELIVERY_POINT:
3755                 retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3756                 break;
3757 
3758         case SCTP_INITMSG:
3759                 retval = sctp_setsockopt_initmsg(sk, optval, optlen);
3760                 break;
3761         case SCTP_DEFAULT_SEND_PARAM:
3762                 retval = sctp_setsockopt_default_send_param(sk, optval,
3763                                                             optlen);
3764                 break;
3765         case SCTP_DEFAULT_SNDINFO:
3766                 retval = sctp_setsockopt_default_sndinfo(sk, optval, optlen);
3767                 break;
3768         case SCTP_PRIMARY_ADDR:
3769                 retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
3770                 break;
3771         case SCTP_SET_PEER_PRIMARY_ADDR:
3772                 retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
3773                 break;
3774         case SCTP_NODELAY:
3775                 retval = sctp_setsockopt_nodelay(sk, optval, optlen);
3776                 break;
3777         case SCTP_RTOINFO:
3778                 retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
3779                 break;
3780         case SCTP_ASSOCINFO:
3781                 retval = sctp_setsockopt_associnfo(sk, optval, optlen);
3782                 break;
3783         case SCTP_I_WANT_MAPPED_V4_ADDR:
3784                 retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
3785                 break;
3786         case SCTP_MAXSEG:
3787                 retval = sctp_setsockopt_maxseg(sk, optval, optlen);
3788                 break;
3789         case SCTP_ADAPTATION_LAYER:
3790                 retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
3791                 break;
3792         case SCTP_CONTEXT:
3793                 retval = sctp_setsockopt_context(sk, optval, optlen);
3794                 break;
3795         case SCTP_FRAGMENT_INTERLEAVE:
3796                 retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
3797                 break;
3798         case SCTP_MAX_BURST:
3799                 retval = sctp_setsockopt_maxburst(sk, optval, optlen);
3800                 break;
3801         case SCTP_AUTH_CHUNK:
3802                 retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
3803                 break;
3804         case SCTP_HMAC_IDENT:
3805                 retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
3806                 break;
3807         case SCTP_AUTH_KEY:
3808                 retval = sctp_setsockopt_auth_key(sk, optval, optlen);
3809                 break;
3810         case SCTP_AUTH_ACTIVE_KEY:
3811                 retval = sctp_setsockopt_active_key(sk, optval, optlen);
3812                 break;
3813         case SCTP_AUTH_DELETE_KEY:
3814                 retval = sctp_setsockopt_del_key(sk, optval, optlen);
3815                 break;
3816         case SCTP_AUTO_ASCONF:
3817                 retval = sctp_setsockopt_auto_asconf(sk, optval, optlen);
3818                 break;
3819         case SCTP_PEER_ADDR_THLDS:
3820                 retval = sctp_setsockopt_paddr_thresholds(sk, optval, optlen);
3821                 break;
3822         case SCTP_RECVRCVINFO:
3823                 retval = sctp_setsockopt_recvrcvinfo(sk, optval, optlen);
3824                 break;
3825         case SCTP_RECVNXTINFO:
3826                 retval = sctp_setsockopt_recvnxtinfo(sk, optval, optlen);
3827                 break;
3828         default:
3829                 retval = -ENOPROTOOPT;
3830                 break;
3831         }
3832 
3833         release_sock(sk);
3834 
3835 out_nounlock:
3836         return retval;
3837 }
3838 
3839 /* API 3.1.6 connect() - UDP Style Syntax
3840  *
3841  * An application may use the connect() call in the UDP model to initiate an
3842  * association without sending data.
3843  *
3844  * The syntax is:
3845  *
3846  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
3847  *
3848  * sd: the socket descriptor to have a new association added to.
3849  *
3850  * nam: the address structure (either struct sockaddr_in or struct
3851  *    sockaddr_in6 defined in RFC2553 [7]).
3852  *
3853  * len: the size of the address.
3854  */
3855 static int sctp_connect(struct sock *sk, struct sockaddr *addr,
3856                         int addr_len)
3857 {
3858         int err = 0;
3859         struct sctp_af *af;
3860 
3861         lock_sock(sk);
3862 
3863         pr_debug("%s: sk:%p, sockaddr:%p, addr_len:%d\n", __func__, sk,
3864                  addr, addr_len);
3865 
3866         /* Validate addr_len before calling common connect/connectx routine. */
3867         af = sctp_get_af_specific(addr->sa_family);
3868         if (!af || addr_len < af->sockaddr_len) {
3869                 err = -EINVAL;
3870         } else {
3871                 /* Pass correct addr len to common routine (so it knows there
3872                  * is only one address being passed.
3873                  */
3874                 err = __sctp_connect(sk, addr, af->sockaddr_len, NULL);
3875         }
3876 
3877         release_sock(sk);
3878         return err;
3879 }
3880 
3881 /* FIXME: Write comments. */
3882 static int sctp_disconnect(struct sock *sk, int flags)
3883 {
3884         return -EOPNOTSUPP; /* STUB */
3885 }
3886 
3887 /* 4.1.4 accept() - TCP Style Syntax
3888  *
3889  * Applications use accept() call to remove an established SCTP
3890  * association from the accept queue of the endpoint.  A new socket
3891  * descriptor will be returned from accept() to represent the newly
3892  * formed association.
3893  */
3894 static struct sock *sctp_accept(struct sock *sk, int flags, int *err)
3895 {
3896         struct sctp_sock *sp;
3897         struct sctp_endpoint *ep;
3898         struct sock *newsk = NULL;
3899         struct sctp_association *asoc;
3900         long timeo;
3901         int error = 0;
3902 
3903         lock_sock(sk);
3904 
3905         sp = sctp_sk(sk);
3906         ep = sp->ep;
3907 
3908         if (!sctp_style(sk, TCP)) {
3909                 error = -EOPNOTSUPP;
3910                 goto out;
3911         }
3912 
3913         if (!sctp_sstate(sk, LISTENING)) {
3914                 error = -EINVAL;
3915                 goto out;
3916         }
3917 
3918         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
3919 
3920         error = sctp_wait_for_accept(sk, timeo);
3921         if (error)
3922                 goto out;
3923 
3924         /* We treat the list of associations on the endpoint as the accept
3925          * queue and pick the first association on the list.
3926          */
3927         asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
3928 
3929         newsk = sp->pf->create_accept_sk(sk, asoc);
3930         if (!newsk) {
3931                 error = -ENOMEM;
3932                 goto out;
3933         }
3934 
3935         /* Populate the fields of the newsk from the oldsk and migrate the
3936          * asoc to the newsk.
3937          */
3938         sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
3939 
3940 out:
3941         release_sock(sk);
3942         *err = error;
3943         return newsk;
3944 }
3945 
3946 /* The SCTP ioctl handler. */
3947 static int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
3948 {
3949         int rc = -ENOTCONN;
3950 
3951         lock_sock(sk);
3952 
3953         /*
3954          * SEQPACKET-style sockets in LISTENING state are valid, for
3955          * SCTP, so only discard TCP-style sockets in LISTENING state.
3956          */
3957         if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
3958                 goto out;
3959 
3960         switch (cmd) {
3961         case SIOCINQ: {
3962                 struct sk_buff *skb;
3963                 unsigned int amount = 0;
3964 
3965                 skb = skb_peek(&sk->sk_receive_queue);
3966                 if (skb != NULL) {
3967                         /*
3968                          * We will only return the amount of this packet since
3969                          * that is all that will be read.
3970                          */
3971                         amount = skb->len;
3972                 }
3973                 rc = put_user(amount, (int __user *)arg);
3974                 break;
3975         }
3976         default:
3977                 rc = -ENOIOCTLCMD;
3978                 break;
3979         }
3980 out:
3981         release_sock(sk);
3982         return rc;
3983 }
3984 
3985 /* This is the function which gets called during socket creation to
3986  * initialized the SCTP-specific portion of the sock.
3987  * The sock structure should already be zero-filled memory.
3988  */
3989 static int sctp_init_sock(struct sock *sk)
3990 {
3991         struct net *net = sock_net(sk);
3992         struct sctp_sock *sp;
3993 
3994         pr_debug("%s: sk:%p\n", __func__, sk);
3995 
3996         sp = sctp_sk(sk);
3997 
3998         /* Initialize the SCTP per socket area.  */
3999         switch (sk->sk_type) {
4000         case SOCK_SEQPACKET:
4001                 sp->type = SCTP_SOCKET_UDP;
4002                 break;
4003         case SOCK_STREAM:
4004                 sp->type = SCTP_SOCKET_TCP;
4005                 break;
4006         default:
4007                 return -ESOCKTNOSUPPORT;
4008         }
4009 
4010         /* Initialize default send parameters. These parameters can be
4011          * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
4012          */
4013         sp->default_stream = 0;
4014         sp->default_ppid = 0;
4015         sp->default_flags = 0;
4016         sp->default_context = 0;
4017         sp->default_timetolive = 0;
4018 
4019         sp->default_rcv_context = 0;
4020         sp->max_burst = net->sctp.max_burst;
4021 
4022         sp->sctp_hmac_alg = net->sctp.sctp_hmac_alg;
4023 
4024         /* Initialize default setup parameters. These parameters
4025          * can be modified with the SCTP_INITMSG socket option or
4026          * overridden by the SCTP_INIT CMSG.
4027          */
4028         sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
4029         sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
4030         sp->initmsg.sinit_max_attempts   = net->sctp.max_retrans_init;
4031         sp->initmsg.sinit_max_init_timeo = net->sctp.rto_max;
4032 
4033         /* Initialize default RTO related parameters.  These parameters can
4034          * be modified for with the SCTP_RTOINFO socket option.
4035          */
4036         sp->rtoinfo.srto_initial = net->sctp.rto_initial;
4037         sp->rtoinfo.srto_max     = net->sctp.rto_max;
4038         sp->rtoinfo.srto_min     = net->sctp.rto_min;
4039 
4040         /* Initialize default association related parameters. These parameters
4041          * can be modified with the SCTP_ASSOCINFO socket option.
4042          */
4043         sp->assocparams.sasoc_asocmaxrxt = net->sctp.max_retrans_association;
4044         sp->assocparams.sasoc_number_peer_destinations = 0;
4045         sp->assocparams.sasoc_peer_rwnd = 0;
4046         sp->assocparams.sasoc_local_rwnd = 0;
4047         sp->assocparams.sasoc_cookie_life = net->sctp.valid_cookie_life;
4048 
4049         /* Initialize default event subscriptions. By default, all the
4050          * options are off.
4051          */
4052         memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
4053 
4054         /* Default Peer Address Parameters.  These defaults can
4055          * be modified via SCTP_PEER_ADDR_PARAMS
4056          */
4057         sp->hbinterval  = net->sctp.hb_interval;
4058         sp->pathmaxrxt  = net->sctp.max_retrans_path;
4059         sp->pathmtu     = 0; /* allow default discovery */
4060         sp->sackdelay   = net->sctp.sack_timeout;
4061         sp->sackfreq    = 2;
4062         sp->param_flags = SPP_HB_ENABLE |
4063                           SPP_PMTUD_ENABLE |
4064                           SPP_SACKDELAY_ENABLE;
4065 
4066         /* If enabled no SCTP message fragmentation will be performed.
4067          * Configure through SCTP_DISABLE_FRAGMENTS socket option.
4068          */
4069         sp->disable_fragments = 0;
4070 
4071         /* Enable Nagle algorithm by default.  */
4072         sp->nodelay           = 0;
4073 
4074         sp->recvrcvinfo = 0;
4075         sp->recvnxtinfo = 0;
4076 
4077         /* Enable by default. */
4078         sp->v4mapped          = 1;
4079 
4080         /* Auto-close idle associations after the configured
4081          * number of seconds.  A value of 0 disables this
4082          * feature.  Configure through the SCTP_AUTOCLOSE socket option,
4083          * for UDP-style sockets only.
4084          */
4085         sp->autoclose         = 0;
4086 
4087         /* User specified fragmentation limit. */
4088         sp->user_frag         = 0;
4089 
4090         sp->adaptation_ind = 0;
4091 
4092         sp->pf = sctp_get_pf_specific(sk->sk_family);
4093 
4094         /* Control variables for partial data delivery. */
4095         atomic_set(&sp->pd_mode, 0);
4096         skb_queue_head_init(&sp->pd_lobby);
4097         sp->frag_interleave = 0;
4098 
4099         /* Create a per socket endpoint structure.  Even if we
4100          * change the data structure relationships, this may still
4101          * be useful for storing pre-connect address information.
4102          */
4103         sp->ep = sctp_endpoint_new(sk, GFP_KERNEL);
4104         if (!sp->ep)
4105                 return -ENOMEM;
4106 
4107         sp->hmac = NULL;
4108 
4109         sk->sk_destruct = sctp_destruct_sock;
4110 
4111         SCTP_DBG_OBJCNT_INC(sock);
4112 
4113         local_bh_disable();
4114         percpu_counter_inc(&sctp_sockets_allocated);
4115         sock_prot_inuse_add(net, sk->sk_prot, 1);
4116 
4117         /* Nothing can fail after this block, otherwise
4118          * sctp_destroy_sock() will be called without addr_wq_lock held
4119          */
4120         if (net->sctp.default_auto_asconf) {
4121                 spin_lock(&sock_net(sk)->sctp.addr_wq_lock);
4122                 list_add_tail(&sp->auto_asconf_list,
4123                     &net->sctp.auto_asconf_splist);
4124                 sp->do_auto_asconf = 1;
4125                 spin_unlock(&sock_net(sk)->sctp.addr_wq_lock);
4126         } else {
4127                 sp->do_auto_asconf = 0;
4128         }
4129 
4130         local_bh_enable();
4131 
4132         return 0;
4133 }
4134 
4135 /* Cleanup any SCTP per socket resources. Must be called with
4136  * sock_net(sk)->sctp.addr_wq_lock held if sp->do_auto_asconf is true
4137  */
4138 static void sctp_destroy_sock(struct sock *sk)
4139 {
4140         struct sctp_sock *sp;
4141 
4142         pr_debug("%s: sk:%p\n", __func__, sk);
4143 
4144         /* Release our hold on the endpoint. */
4145         sp = sctp_sk(sk);
4146         /* This could happen during socket init, thus we bail out
4147          * early, since the rest of the below is not setup either.
4148          */
4149         if (sp->ep == NULL)
4150                 return;
4151 
4152         if (sp->do_auto_asconf) {
4153                 sp->do_auto_asconf = 0;
4154                 list_del(&sp->auto_asconf_list);
4155         }
4156         sctp_endpoint_free(sp->ep);
4157         local_bh_disable();
4158         percpu_counter_dec(&sctp_sockets_allocated);
4159         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
4160         local_bh_enable();
4161 }
4162 
4163 /* Triggered when there are no references on the socket anymore */
4164 static void sctp_destruct_sock(struct sock *sk)
4165 {
4166         struct sctp_sock *sp = sctp_sk(sk);
4167 
4168         /* Free up the HMAC transform. */
4169         crypto_free_hash(sp->hmac);
4170 
4171         inet_sock_destruct(sk);
4172 }
4173 
4174 /* API 4.1.7 shutdown() - TCP Style Syntax
4175  *     int shutdown(int socket, int how);
4176  *
4177  *     sd      - the socket descriptor of the association to be closed.
4178  *     how     - Specifies the type of shutdown.  The  values  are
4179  *               as follows:
4180  *               SHUT_RD
4181  *                     Disables further receive operations. No SCTP
4182  *                     protocol action is taken.
4183  *               SHUT_WR
4184  *                     Disables further send operations, and initiates
4185  *                     the SCTP shutdown sequence.
4186  *               SHUT_RDWR
4187  *                     Disables further send  and  receive  operations
4188  *                     and initiates the SCTP shutdown sequence.
4189  */
4190 static void sctp_shutdown(struct sock *sk, int how)
4191 {
4192         struct net *net = sock_net(sk);
4193         struct sctp_endpoint *ep;
4194         struct sctp_association *asoc;
4195 
4196         if (!sctp_style(sk, TCP))
4197                 return;
4198 
4199         if (how & SEND_SHUTDOWN) {
4200                 ep = sctp_sk(sk)->ep;
4201                 if (!list_empty(&ep->asocs)) {
4202                         asoc = list_entry(ep->asocs.next,
4203                                           struct sctp_association, asocs);
4204                         sctp_primitive_SHUTDOWN(net, asoc, NULL);
4205                 }
4206         }
4207 }
4208 
4209 /* 7.2.1 Association Status (SCTP_STATUS)
4210 
4211  * Applications can retrieve current status information about an
4212  * association, including association state, peer receiver window size,
4213  * number of unacked data chunks, and number of data chunks pending
4214  * receipt.  This information is read-only.
4215  */
4216 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
4217                                        char __user *optval,
4218                                        int __user *optlen)
4219 {
4220         struct sctp_status status;
4221         struct sctp_association *asoc = NULL;
4222         struct sctp_transport *transport;
4223         sctp_assoc_t associd;
4224         int retval = 0;
4225 
4226         if (len < sizeof(status)) {
4227                 retval = -EINVAL;
4228                 goto out;
4229         }
4230 
4231         len = sizeof(status);
4232         if (copy_from_user(&status, optval, len)) {
4233                 retval = -EFAULT;
4234                 goto out;
4235         }
4236 
4237         associd = status.sstat_assoc_id;
4238         asoc = sctp_id2assoc(sk, associd);
4239         if (!asoc) {
4240                 retval = -EINVAL;
4241                 goto out;
4242         }
4243 
4244         transport = asoc->peer.primary_path;
4245 
4246         status.sstat_assoc_id = sctp_assoc2id(asoc);
4247         status.sstat_state = sctp_assoc_to_state(asoc);
4248         status.sstat_rwnd =  asoc->peer.rwnd;
4249         status.sstat_unackdata = asoc->unack_data;
4250 
4251         status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
4252         status.sstat_instrms = asoc->c.sinit_max_instreams;
4253         status.sstat_outstrms = asoc->c.sinit_num_ostreams;
4254         status.sstat_fragmentation_point = asoc->frag_point;
4255         status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
4256         memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
4257                         transport->af_specific->sockaddr_len);
4258         /* Map ipv4 address into v4-mapped-on-v6 address.  */
4259         sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
4260                 (union sctp_addr *)&status.sstat_primary.spinfo_address);
4261         status.sstat_primary.spinfo_state = transport->state;
4262         status.sstat_primary.spinfo_cwnd = transport->cwnd;
4263         status.sstat_primary.spinfo_srtt = transport->srtt;
4264         status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
4265         status.sstat_primary.spinfo_mtu = transport->pathmtu;
4266 
4267         if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
4268                 status.sstat_primary.spinfo_state = SCTP_ACTIVE;
4269 
4270         if (put_user(len, optlen)) {
4271                 retval = -EFAULT;
4272                 goto out;
4273         }
4274 
4275         pr_debug("%s: len:%d, state:%d, rwnd:%d, assoc_id:%d\n",
4276                  __func__, len, status.sstat_state, status.sstat_rwnd,
4277                  status.sstat_assoc_id);
4278 
4279         if (copy_to_user(optval, &status, len)) {
4280                 retval = -EFAULT;
4281                 goto out;
4282         }
4283 
4284 out:
4285         return retval;
4286 }
4287 
4288 
4289 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
4290  *
4291  * Applications can retrieve information about a specific peer address
4292  * of an association, including its reachability state, congestion
4293  * window, and retransmission timer values.  This information is
4294  * read-only.
4295  */
4296 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
4297                                           char __user *optval,
4298                                           int __user *optlen)
4299 {
4300         struct sctp_paddrinfo pinfo;
4301         struct sctp_transport *transport;
4302         int retval = 0;
4303 
4304         if (len < sizeof(pinfo)) {
4305                 retval = -EINVAL;
4306                 goto out;
4307         }
4308 
4309         len = sizeof(pinfo);
4310         if (copy_from_user(&pinfo, optval, len)) {
4311                 retval = -EFAULT;
4312                 goto out;
4313         }
4314 
4315         transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
4316                                            pinfo.spinfo_assoc_id);
4317         if (!transport)
4318                 return -EINVAL;
4319 
4320         pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
4321         pinfo.spinfo_state = transport->state;
4322         pinfo.spinfo_cwnd = transport->cwnd;
4323         pinfo.spinfo_srtt = transport->srtt;
4324         pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
4325         pinfo.spinfo_mtu = transport->pathmtu;
4326 
4327         if (pinfo.spinfo_state == SCTP_UNKNOWN)
4328                 pinfo.spinfo_state = SCTP_ACTIVE;
4329 
4330         if (put_user(len, optlen)) {
4331                 retval = -EFAULT;
4332                 goto out;
4333         }
4334 
4335         if (copy_to_user(optval, &pinfo, len)) {
4336                 retval = -EFAULT;
4337                 goto out;
4338         }
4339 
4340 out:
4341         return retval;
4342 }
4343 
4344 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
4345  *
4346  * This option is a on/off flag.  If enabled no SCTP message
4347  * fragmentation will be performed.  Instead if a message being sent
4348  * exceeds the current PMTU size, the message will NOT be sent and
4349  * instead a error will be indicated to the user.
4350  */
4351 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
4352                                         char __user *optval, int __user *optlen)
4353 {
4354         int val;
4355 
4356         if (len < sizeof(int))
4357                 return -EINVAL;
4358 
4359         len = sizeof(int);
4360         val = (sctp_sk(sk)->disable_fragments == 1);
4361         if (put_user(len, optlen))
4362                 return -EFAULT;
4363         if (copy_to_user(optval, &val, len))
4364                 return -EFAULT;
4365         return 0;
4366 }
4367 
4368 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
4369  *
4370  * This socket option is used to specify various notifications and
4371  * ancillary data the user wishes to receive.
4372  */
4373 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
4374                                   int __user *optlen)
4375 {
4376         if (len <= 0)
4377                 return -EINVAL;
4378         if (len > sizeof(struct sctp_event_subscribe))
4379                 len = sizeof(struct sctp_event_subscribe);
4380         if (put_user(len, optlen))
4381                 return -EFAULT;
4382         if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
4383                 return -EFAULT;
4384         return 0;
4385 }
4386 
4387 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
4388  *
4389  * This socket option is applicable to the UDP-style socket only.  When
4390  * set it will cause associations that are idle for more than the
4391  * specified number of seconds to automatically close.  An association
4392  * being idle is defined an association that has NOT sent or received
4393  * user data.  The special value of '' indicates that no automatic
4394  * close of any associations should be performed.  The option expects an
4395  * integer defining the number of seconds of idle time before an
4396  * association is closed.
4397  */
4398 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
4399 {
4400         /* Applicable to UDP-style socket only */
4401         if (sctp_style(sk, TCP))
4402                 return -EOPNOTSUPP;
4403         if (len < sizeof(int))
4404                 return -EINVAL;
4405         len = sizeof(int);
4406         if (put_user(len, optlen))
4407                 return -EFAULT;
4408         if (copy_to_user(optval, &sctp_sk(sk)->autoclose, sizeof(int)))
4409                 return -EFAULT;
4410         return 0;
4411 }
4412 
4413 /* Helper routine to branch off an association to a new socket.  */
4414 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp)
4415 {
4416         struct sctp_association *asoc = sctp_id2assoc(sk, id);
4417         struct sctp_sock *sp = sctp_sk(sk);
4418         struct socket *sock;
4419         int err = 0;
4420 
4421         if (!asoc)
4422                 return -EINVAL;
4423 
4424         /* An association cannot be branched off from an already peeled-off
4425          * socket, nor is this supported for tcp style sockets.
4426          */
4427         if (!sctp_style(sk, UDP))
4428                 return -EINVAL;
4429 
4430         /* Create a new socket.  */
4431         err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
4432         if (err < 0)
4433                 return err;
4434 
4435         sctp_copy_sock(sock->sk, sk, asoc);
4436 
4437         /* Make peeled-off sockets more like 1-1 accepted sockets.
4438          * Set the daddr and initialize id to something more random
4439          */
4440         sp->pf->to_sk_daddr(&asoc->peer.primary_addr, sk);
4441 
4442         /* Populate the fields of the newsk from the oldsk and migrate the
4443          * asoc to the newsk.
4444          */
4445         sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
4446 
4447         *sockp = sock;
4448 
4449         return err;
4450 }
4451 EXPORT_SYMBOL(sctp_do_peeloff);
4452 
4453 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
4454 {
4455         sctp_peeloff_arg_t peeloff;
4456         struct socket *newsock;
4457         struct file *newfile;
4458         int retval = 0;
4459 
4460         if (len < sizeof(sctp_peeloff_arg_t))
4461                 return -EINVAL;
4462         len = sizeof(sctp_peeloff_arg_t);
4463         if (copy_from_user(&peeloff, optval, len))
4464                 return -EFAULT;
4465 
4466         retval = sctp_do_peeloff(sk, peeloff.associd, &newsock);
4467         if (retval < 0)
4468                 goto out;
4469 
4470         /* Map the socket to an unused fd that can be returned to the user.  */
4471         retval = get_unused_fd_flags(0);
4472         if (retval < 0) {
4473                 sock_release(newsock);
4474                 goto out;
4475         }
4476 
4477         newfile = sock_alloc_file(newsock, 0, NULL);
4478         if (unlikely(IS_ERR(newfile))) {
4479                 put_unused_fd(retval);
4480                 sock_release(newsock);
4481                 return PTR_ERR(newfile);
4482         }
4483 
4484         pr_debug("%s: sk:%p, newsk:%p, sd:%d\n", __func__, sk, newsock->sk,
4485                  retval);
4486 
4487         /* Return the fd mapped to the new socket.  */
4488         if (put_user(len, optlen)) {
4489                 fput(newfile);
4490                 put_unused_fd(retval);
4491                 return -EFAULT;
4492         }
4493         peeloff.sd = retval;
4494         if (copy_to_user(optval, &peeloff, len)) {
4495                 fput(newfile);
4496                 put_unused_fd(retval);
4497                 return -EFAULT;
4498         }
4499         fd_install(retval, newfile);
4500 out:
4501         return retval;
4502 }
4503 
4504 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
4505  *
4506  * Applications can enable or disable heartbeats for any peer address of
4507  * an association, modify an address's heartbeat interval, force a
4508  * heartbeat to be sent immediately, and adjust the address's maximum
4509  * number of retransmissions sent before an address is considered
4510  * unreachable.  The following structure is used to access and modify an
4511  * address's parameters:
4512  *
4513  *  struct sctp_paddrparams {
4514  *     sctp_assoc_t            spp_assoc_id;
4515  *     struct sockaddr_storage spp_address;
4516  *     uint32_t                spp_hbinterval;
4517  *     uint16_t                spp_pathmaxrxt;
4518  *     uint32_t                spp_pathmtu;
4519  *     uint32_t                spp_sackdelay;
4520  *     uint32_t                spp_flags;
4521  * };
4522  *
4523  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
4524  *                     application, and identifies the association for
4525  *                     this query.
4526  *   spp_address     - This specifies which address is of interest.
4527  *   spp_hbinterval  - This contains the value of the heartbeat interval,
4528  *                     in milliseconds.  If a  value of zero
4529  *                     is present in this field then no changes are to
4530  *                     be made to this parameter.
4531  *   spp_pathmaxrxt  - This contains the maximum number of
4532  *                     retransmissions before this address shall be
4533  *                     considered unreachable. If a  value of zero
4534  *                     is present in this field then no changes are to
4535  *                     be made to this parameter.
4536  *   spp_pathmtu     - When Path MTU discovery is disabled the value
4537  *                     specified here will be the "fixed" path mtu.
4538  *                     Note that if the spp_address field is empty
4539  *                     then all associations on this address will
4540  *                     have this fixed path mtu set upon them.
4541  *
4542  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
4543  *                     the number of milliseconds that sacks will be delayed
4544  *                     for. This value will apply to all addresses of an
4545  *                     association if the spp_address field is empty. Note
4546  *                     also, that if delayed sack is enabled and this
4547  *                     value is set to 0, no change is made to the last
4548  *                     recorded delayed sack timer value.
4549  *
4550  *   spp_flags       - These flags are used to control various features
4551  *                     on an association. The flag field may contain
4552  *                     zero or more of the following options.
4553  *
4554  *                     SPP_HB_ENABLE  - Enable heartbeats on the
4555  *                     specified address. Note that if the address
4556  *                     field is empty all addresses for the association
4557  *                     have heartbeats enabled upon them.
4558  *
4559  *                     SPP_HB_DISABLE - Disable heartbeats on the
4560  *                     speicifed address. Note that if the address
4561  *                     field is empty all addresses for the association
4562  *                     will have their heartbeats disabled. Note also
4563  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
4564  *                     mutually exclusive, only one of these two should
4565  *                     be specified. Enabling both fields will have
4566  *                     undetermined results.
4567  *
4568  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
4569  *                     to be made immediately.
4570  *
4571  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
4572  *                     discovery upon the specified address. Note that
4573  *                     if the address feild is empty then all addresses
4574  *                     on the association are effected.
4575  *
4576  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
4577  *                     discovery upon the specified address. Note that
4578  *                     if the address feild is empty then all addresses
4579  *                     on the association are effected. Not also that
4580  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
4581  *                     exclusive. Enabling both will have undetermined
4582  *                     results.
4583  *
4584  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
4585  *                     on delayed sack. The time specified in spp_sackdelay
4586  *                     is used to specify the sack delay for this address. Note
4587  *                     that if spp_address is empty then all addresses will
4588  *                     enable delayed sack and take on the sack delay
4589  *                     value specified in spp_sackdelay.
4590  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
4591  *                     off delayed sack. If the spp_address field is blank then
4592  *                     delayed sack is disabled for the entire association. Note
4593  *                     also that this field is mutually exclusive to
4594  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
4595  *                     results.
4596  */
4597 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
4598                                             char __user *optval, int __user *optlen)
4599 {
4600         struct sctp_paddrparams  params;
4601         struct sctp_transport   *trans = NULL;
4602         struct sctp_association *asoc = NULL;
4603         struct sctp_sock        *sp = sctp_sk(sk);
4604 
4605         if (len < sizeof(struct sctp_paddrparams))
4606                 return -EINVAL;
4607         len = sizeof(struct sctp_paddrparams);
4608         if (copy_from_user(&params, optval, len))
4609                 return -EFAULT;
4610 
4611         /* If an address other than INADDR_ANY is specified, and
4612          * no transport is found, then the request is invalid.
4613          */
4614         if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
4615                 trans = sctp_addr_id2transport(sk, &params.spp_address,
4616                                                params.spp_assoc_id);
4617                 if (!trans) {
4618                         pr_debug("%s: failed no transport\n", __func__);
4619                         return -EINVAL;
4620                 }
4621         }
4622 
4623         /* Get association, if assoc_id != 0 and the socket is a one
4624          * to many style socket, and an association was not found, then
4625          * the id was invalid.
4626          */
4627         asoc = sctp_id2assoc(sk, params.spp_assoc_id);
4628         if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
4629                 pr_debug("%s: failed no association\n", __func__);
4630                 return -EINVAL;
4631         }
4632 
4633         if (trans) {
4634                 /* Fetch transport values. */
4635                 params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
4636                 params.spp_pathmtu    = trans->pathmtu;
4637                 params.spp_pathmaxrxt = trans->pathmaxrxt;
4638                 params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
4639 
4640                 /*draft-11 doesn't say what to return in spp_flags*/
4641                 params.spp_flags      = trans->param_flags;
4642         } else if (asoc) {
4643                 /* Fetch association values. */
4644                 params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
4645                 params.spp_pathmtu    = asoc->pathmtu;
4646                 params.spp_pathmaxrxt = asoc->pathmaxrxt;
4647                 params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
4648 
4649                 /*draft-11 doesn't say what to return in spp_flags*/
4650                 params.spp_flags      = asoc->param_flags;
4651         } else {
4652                 /* Fetch socket values. */
4653                 params.spp_hbinterval = sp->hbinterval;
4654                 params.spp_pathmtu    = sp->pathmtu;
4655                 params.spp_sackdelay  = sp->sackdelay;
4656                 params.spp_pathmaxrxt = sp->pathmaxrxt;
4657 
4658                 /*draft-11 doesn't say what to return in spp_flags*/
4659                 params.spp_flags      = sp->param_flags;
4660         }
4661 
4662         if (copy_to_user(optval, &params, len))
4663                 return -EFAULT;
4664 
4665         if (put_user(len, optlen))
4666                 return -EFAULT;
4667 
4668         return 0;
4669 }
4670 
4671 /*
4672  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
4673  *
4674  * This option will effect the way delayed acks are performed.  This
4675  * option allows you to get or set the delayed ack time, in
4676  * milliseconds.  It also allows changing the delayed ack frequency.
4677  * Changing the frequency to 1 disables the delayed sack algorithm.  If
4678  * the assoc_id is 0, then this sets or gets the endpoints default
4679  * values.  If the assoc_id field is non-zero, then the set or get
4680  * effects the specified association for the one to many model (the
4681  * assoc_id field is ignored by the one to one model).  Note that if
4682  * sack_delay or sack_freq are 0 when setting this option, then the
4683  * current values will remain unchanged.
4684  *
4685  * struct sctp_sack_info {
4686  *     sctp_assoc_t            sack_assoc_id;
4687  *     uint32_t                sack_delay;
4688  *     uint32_t                sack_freq;
4689  * };
4690  *
4691  * sack_assoc_id -  This parameter, indicates which association the user
4692  *    is performing an action upon.  Note that if this field's value is
4693  *    zero then the endpoints default value is changed (effecting future
4694  *    associations only).
4695  *
4696  * sack_delay -  This parameter contains the number of milliseconds that
4697  *    the user is requesting the delayed ACK timer be set to.  Note that
4698  *    this value is defined in the standard to be between 200 and 500
4699  *    milliseconds.
4700  *
4701  * sack_freq -  This parameter contains the number of packets that must
4702  *    be received before a sack is sent without waiting for the delay
4703  *    timer to expire.  The default value for this is 2, setting this
4704  *    value to 1 will disable the delayed sack algorithm.
4705  */
4706 static int sctp_getsockopt_delayed_ack(struct sock *sk, int len,
4707                                             char __user *optval,
4708                                             int __user *optlen)
4709 {
4710         struct sctp_sack_info    params;
4711         struct sctp_association *asoc = NULL;
4712         struct sctp_sock        *sp = sctp_sk(sk);
4713 
4714         if (len >= sizeof(struct sctp_sack_info)) {
4715                 len = sizeof(struct sctp_sack_info);
4716 
4717                 if (copy_from_user(&params, optval, len))
4718                         return -EFAULT;
4719         } else if (len == sizeof(struct sctp_assoc_value)) {
4720                 pr_warn_ratelimited(DEPRECATED
4721                                     "%s (pid %d) "
4722                                     "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
4723                                     "Use struct sctp_sack_info instead\n",
4724                                     current->comm, task_pid_nr(current));
4725                 if (copy_from_user(&params, optval, len))
4726                         return -EFAULT;
4727         } else
4728                 return -EINVAL;
4729 
4730         /* Get association, if sack_assoc_id != 0 and the socket is a one
4731          * to many style socket, and an association was not found, then
4732          * the id was invalid.
4733          */
4734         asoc = sctp_id2assoc(sk, params.sack_assoc_id);
4735         if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
4736                 return -EINVAL;
4737 
4738         if (asoc) {
4739                 /* Fetch association values. */
4740                 if (asoc->param_flags & SPP_SACKDELAY_ENABLE) {
4741                         params.sack_delay = jiffies_to_msecs(
4742                                 asoc->sackdelay);
4743                         params.sack_freq = asoc->sackfreq;
4744 
4745                 } else {
4746                         params.sack_delay = 0;
4747                         params.sack_freq = 1;
4748                 }
4749         } else {
4750                 /* Fetch socket values. */
4751                 if (sp->param_flags & SPP_SACKDELAY_ENABLE) {
4752                         params.sack_delay  = sp->sackdelay;
4753                         params.sack_freq = sp->sackfreq;
4754                 } else {
4755                         params.sack_delay  = 0;
4756                         params.sack_freq = 1;
4757                 }
4758         }
4759 
4760         if (copy_to_user(optval, &params, len))
4761                 return -EFAULT;
4762 
4763         if (put_user(len, optlen))
4764                 return -EFAULT;
4765 
4766         return 0;
4767 }
4768 
4769 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
4770  *
4771  * Applications can specify protocol parameters for the default association
4772  * initialization.  The option name argument to setsockopt() and getsockopt()
4773  * is SCTP_INITMSG.
4774  *
4775  * Setting initialization parameters is effective only on an unconnected
4776  * socket (for UDP-style sockets only future associations are effected
4777  * by the change).  With TCP-style sockets, this option is inherited by
4778  * sockets derived from a listener socket.
4779  */
4780 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
4781 {
4782         if (len < sizeof(struct sctp_initmsg))
4783                 return -EINVAL;
4784         len = sizeof(struct sctp_initmsg);
4785         if (put_user(len, optlen))
4786                 return -EFAULT;
4787         if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
4788                 return -EFAULT;
4789         return 0;
4790 }
4791 
4792 
4793 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
4794                                       char __user *optval, int __user *optlen)
4795 {
4796         struct sctp_association *asoc;
4797         int cnt = 0;
4798         struct sctp_getaddrs getaddrs;
4799         struct sctp_transport *from;
4800         void __user *to;
4801         union sctp_addr temp;
4802         struct sctp_sock *sp = sctp_sk(sk);
4803         int addrlen;
4804         size_t space_left;
4805         int bytes_copied;
4806 
4807         if (len < sizeof(struct sctp_getaddrs))
4808                 return -EINVAL;
4809 
4810         if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4811                 return -EFAULT;
4812 
4813         /* For UDP-style sockets, id specifies the association to query.  */
4814         asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4815         if (!asoc)
4816                 return -EINVAL;
4817 
4818         to = optval + offsetof(struct sctp_getaddrs, addrs);
4819         space_left = len - offsetof(struct sctp_getaddrs, addrs);
4820 
4821         list_for_each_entry(from, &asoc->peer.transport_addr_list,
4822                                 transports) {
4823                 memcpy(&temp, &from->ipaddr, sizeof(temp));
4824                 addrlen = sctp_get_pf_specific(sk->sk_family)
4825                               ->addr_to_user(sp, &temp);
4826                 if (space_left < addrlen)
4827                         return -ENOMEM;
4828                 if (copy_to_user(to, &temp, addrlen))
4829                         return -EFAULT;
4830                 to += addrlen;
4831                 cnt++;
4832                 space_left -= addrlen;
4833         }
4834 
4835         if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
4836                 return -EFAULT;
4837         bytes_copied = ((char __user *)to) - optval;
4838         if (put_user(bytes_copied, optlen))
4839                 return -EFAULT;
4840 
4841         return 0;
4842 }
4843 
4844 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
4845                             size_t space_left, int *bytes_copied)
4846 {
4847         struct sctp_sockaddr_entry *addr;
4848         union sctp_addr temp;
4849         int cnt = 0;
4850         int addrlen;
4851         struct net *net = sock_net(sk);
4852 
4853         rcu_read_lock();
4854         list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
4855                 if (!addr->valid)
4856                         continue;
4857 
4858                 if ((PF_INET == sk->sk_family) &&
4859                     (AF_INET6 == addr->a.sa.sa_family))
4860                         continue;
4861                 if ((PF_INET6 == sk->sk_family) &&
4862                     inet_v6_ipv6only(sk) &&
4863                     (AF_INET == addr->a.sa.sa_family))
4864                         continue;
4865                 memcpy(&temp, &addr->a, sizeof(temp));
4866                 if (!temp.v4.sin_port)
4867                         temp.v4.sin_port = htons(port);
4868 
4869                 addrlen = sctp_get_pf_specific(sk->sk_family)
4870                               ->addr_to_user(sctp_sk(sk), &temp);
4871 
4872                 if (space_left < addrlen) {
4873                         cnt =  -ENOMEM;
4874                         break;
4875                 }
4876                 memcpy(to, &temp, addrlen);
4877 
4878                 to += addrlen;
4879                 cnt++;
4880                 space_left -= addrlen;
4881                 *bytes_copied += addrlen;
4882         }
4883         rcu_read_unlock();
4884 
4885         return cnt;
4886 }
4887 
4888 
4889 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
4890                                        char __user *optval, int __user *optlen)
4891 {
4892         struct sctp_bind_addr *bp;
4893         struct sctp_association *asoc;
4894         int cnt = 0;
4895         struct sctp_getaddrs getaddrs;
4896         struct sctp_sockaddr_entry *addr;
4897         void __user *to;
4898         union sctp_addr temp;
4899         struct sctp_sock *sp = sctp_sk(sk);
4900         int addrlen;
4901         int err = 0;
4902         size_t space_left;
4903         int bytes_copied = 0;
4904         void *addrs;
4905         void *buf;
4906 
4907         if (len < sizeof(struct sctp_getaddrs))
4908                 return -EINVAL;
4909 
4910         if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4911                 return -EFAULT;
4912 
4913         /*
4914          *  For UDP-style sockets, id specifies the association to query.
4915          *  If the id field is set to the value '' then the locally bound
4916          *  addresses are returned without regard to any particular
4917          *  association.
4918          */
4919         if (0 == getaddrs.assoc_id) {
4920                 bp = &sctp_sk(sk)->ep->base.bind_addr;
4921         } else {
4922                 asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4923                 if (!asoc)
4924                         return -EINVAL;
4925                 bp = &asoc->base.bind_addr;
4926         }
4927 
4928         to = optval + offsetof(struct sctp_getaddrs, addrs);
4929         space_left = len - offsetof(struct sctp_getaddrs, addrs);
4930 
4931         addrs = kmalloc(space_left, GFP_KERNEL);
4932         if (!addrs)
4933                 return -ENOMEM;
4934 
4935         /* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4936          * addresses from the global local address list.
4937          */
4938         if (sctp_list_single_entry(&bp->address_list)) {
4939                 addr = list_entry(bp->address_list.next,
4940                                   struct sctp_sockaddr_entry, list);
4941                 if (sctp_is_any(sk, &addr->a)) {
4942                         cnt = sctp_copy_laddrs(sk, bp->port, addrs,
4943                                                 space_left, &bytes_copied);
4944                         if (cnt < 0) {
4945                                 err = cnt;
4946                                 goto out;
4947                         }
4948                         goto copy_getaddrs;
4949                 }
4950         }
4951 
4952         buf = addrs;
4953         /* Protection on the bound address list is not needed since
4954          * in the socket option context we hold a socket lock and
4955          * thus the bound address list can't change.
4956          */
4957         list_for_each_entry(addr, &bp->address_list, list) {
4958                 memcpy(&temp, &addr->a, sizeof(temp));
4959                 addrlen = sctp_get_pf_specific(sk->sk_family)
4960                               ->addr_to_user(sp, &temp);
4961                 if (space_left < addrlen) {
4962                         err =  -ENOMEM; /*fixme: right error?*/
4963                         goto out;
4964                 }
4965                 memcpy(buf, &temp, addrlen);
4966                 buf += addrlen;
4967                 bytes_copied += addrlen;
4968                 cnt++;
4969                 space_left -= addrlen;
4970         }
4971 
4972 copy_getaddrs:
4973         if (copy_to_user(to, addrs, bytes_copied)) {
4974                 err = -EFAULT;
4975                 goto out;
4976         }
4977         if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
4978                 err = -EFAULT;
4979                 goto out;
4980         }
4981         if (put_user(bytes_copied, optlen))
4982                 err = -EFAULT;
4983 out:
4984         kfree(addrs);
4985         return err;
4986 }
4987 
4988 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
4989  *
4990  * Requests that the local SCTP stack use the enclosed peer address as
4991  * the association primary.  The enclosed address must be one of the
4992  * association peer's addresses.
4993  */
4994 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
4995                                         char __user *optval, int __user *optlen)
4996 {
4997         struct sctp_prim prim;
4998         struct sctp_association *asoc;
4999         struct sctp_sock *sp = sctp_sk(sk);
5000 
5001         if (len < sizeof(struct sctp_prim))
5002                 return -EINVAL;
5003 
5004         len = sizeof(struct sctp_prim);
5005 
5006         if (copy_from_user(&prim, optval, len))
5007                 return -EFAULT;
5008 
5009         asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
5010         if (!asoc)
5011                 return -EINVAL;
5012 
5013         if (!asoc->peer.primary_path)
5014                 return -ENOTCONN;
5015 
5016         memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
5017                 asoc->peer.primary_path->af_specific->sockaddr_len);
5018 
5019         sctp_get_pf_specific(sk->sk_family)->addr_to_user(sp,
5020                         (union sctp_addr *)&prim.ssp_addr);
5021 
5022         if (put_user(len, optlen))
5023                 return -EFAULT;
5024         if (copy_to_user(optval, &prim, len))
5025                 return -EFAULT;
5026 
5027         return 0;
5028 }
5029 
5030 /*
5031  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
5032  *
5033  * Requests that the local endpoint set the specified Adaptation Layer
5034  * Indication parameter for all future INIT and INIT-ACK exchanges.
5035  */
5036 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
5037                                   char __user *optval, int __user *optlen)
5038 {
5039         struct sctp_setadaptation adaptation;
5040 
5041         if (len < sizeof(struct sctp_setadaptation))
5042                 return -EINVAL;
5043 
5044         len = sizeof(struct sctp_setadaptation);
5045 
5046         adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
5047 
5048         if (put_user(len, optlen))
5049                 return -EFAULT;
5050         if (copy_to_user(optval, &adaptation, len))
5051                 return -EFAULT;
5052 
5053         return 0;
5054 }
5055 
5056 /*
5057  *
5058  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
5059  *
5060  *   Applications that wish to use the sendto() system call may wish to
5061  *   specify a default set of parameters that would normally be supplied
5062  *   through the inclusion of ancillary data.  This socket option allows
5063  *   such an application to set the default sctp_sndrcvinfo structure.
5064 
5065 
5066  *   The application that wishes to use this socket option simply passes
5067  *   in to this call the sctp_sndrcvinfo structure defined in Section
5068  *   5.2.2) The input parameters accepted by this call include
5069  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
5070  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
5071  *   to this call if the caller is using the UDP model.
5072  *
5073  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
5074  */
5075 static int sctp_getsockopt_default_send_param(struct sock *sk,
5076                                         int len, char __user *optval,
5077                                         int __user *optlen)
5078 {
5079         struct sctp_sock *sp = sctp_sk(sk);
5080         struct sctp_association *asoc;
5081         struct sctp_sndrcvinfo info;
5082 
5083         if (len < sizeof(info))
5084                 return -EINVAL;
5085 
5086         len = sizeof(info);
5087 
5088         if (copy_from_user(&info, optval, len))
5089                 return -EFAULT;
5090 
5091         asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
5092         if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
5093                 return -EINVAL;
5094         if (asoc) {
5095                 info.sinfo_stream = asoc->default_stream;
5096                 info.sinfo_flags = asoc->default_flags;
5097                 info.sinfo_ppid = asoc->default_ppid;
5098                 info.sinfo_context = asoc->default_context;
5099                 info.sinfo_timetolive = asoc->default_timetolive;
5100         } else {
5101                 info.sinfo_stream = sp->default_stream;
5102                 info.sinfo_flags = sp->default_flags;
5103                 info.sinfo_ppid = sp->default_ppid;
5104                 info.sinfo_context = sp->default_context;
5105                 info.sinfo_timetolive = sp->default_timetolive;
5106         }
5107 
5108         if (put_user(len, optlen))
5109                 return -EFAULT;
5110         if (copy_to_user(optval, &info, len))
5111                 return -EFAULT;
5112 
5113         return 0;
5114 }
5115 
5116 /* RFC6458, Section 8.1.31. Set/get Default Send Parameters
5117  * (SCTP_DEFAULT_SNDINFO)
5118  */
5119 static int sctp_getsockopt_default_sndinfo(struct sock *sk, int len,
5120                                            char __user *optval,
5121                                            int __user *optlen)
5122 {
5123         struct sctp_sock *sp = sctp_sk(sk);
5124         struct sctp_association *asoc;
5125         struct sctp_sndinfo info;
5126 
5127         if (len < sizeof(info))
5128                 return -EINVAL;
5129 
5130         len = sizeof(info);
5131 
5132         if (copy_from_user(&info, optval, len))
5133                 return -EFAULT;
5134 
5135         asoc = sctp_id2assoc(sk, info.snd_assoc_id);
5136         if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
5137                 return -EINVAL;
5138         if (asoc) {
5139                 info.snd_sid = asoc->default_stream;
5140                 info.snd_flags = asoc->default_flags;
5141                 info.snd_ppid = asoc->default_ppid;
5142                 info.snd_context = asoc->default_context;
5143         } else {
5144                 info.snd_sid = sp->default_stream;
5145                 info.snd_flags = sp->default_flags;
5146                 info.snd_ppid = sp->default_ppid;
5147                 info.snd_context = sp->default_context;
5148         }
5149 
5150         if (put_user(len, optlen))
5151                 return -EFAULT;
5152         if (copy_to_user(optval, &info, len))
5153                 return -EFAULT;
5154 
5155         return 0;
5156 }
5157 
5158 /*
5159  *
5160  * 7.1.5 SCTP_NODELAY
5161  *
5162  * Turn on/off any Nagle-like algorithm.  This means that packets are
5163  * generally sent as soon as possible and no unnecessary delays are
5164  * introduced, at the cost of more packets in the network.  Expects an
5165  * integer boolean flag.
5166  */
5167 
5168 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
5169                                    char __user *optval, int __user *optlen)
5170 {
5171         int val;
5172 
5173         if (len < sizeof(int))
5174                 return -EINVAL;
5175 
5176         len = sizeof(int);
5177         val = (sctp_sk(sk)->nodelay == 1);
5178         if (put_user(len, optlen))
5179                 return -EFAULT;
5180         if (copy_to_user(optval, &val, len))
5181                 return -EFAULT;
5182         return 0;
5183 }
5184 
5185 /*
5186  *
5187  * 7.1.1 SCTP_RTOINFO
5188  *
5189  * The protocol parameters used to initialize and bound retransmission
5190  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
5191  * and modify these parameters.
5192  * All parameters are time values, in milliseconds.  A value of 0, when
5193  * modifying the parameters, indicates that the current value should not
5194  * be changed.
5195  *
5196  */
5197 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
5198                                 char __user *optval,
5199                                 int __user *optlen) {
5200         struct sctp_rtoinfo rtoinfo;
5201         struct sctp_association *asoc;
5202 
5203         if (len < sizeof (struct sctp_rtoinfo))
5204                 return -EINVAL;
5205 
5206         len = sizeof(struct sctp_rtoinfo);
5207 
5208         if (copy_from_user(&rtoinfo, optval, len))
5209                 return -EFAULT;
5210 
5211         asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
5212 
5213         if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
5214                 return -EINVAL;
5215 
5216         /* Values corresponding to the specific association. */
5217         if (asoc) {
5218                 rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
5219                 rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
5220                 rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
5221         } else {
5222                 /* Values corresponding to the endpoint. */
5223                 struct sctp_sock *sp = sctp_sk(sk);
5224 
5225                 rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
5226                 rtoinfo.srto_max = sp->rtoinfo.srto_max;
5227                 rtoinfo.srto_min = sp->rtoinfo.srto_min;
5228         }
5229 
5230         if (put_user(len, optlen))
5231                 return -EFAULT;
5232 
5233         if (copy_to_user(optval, &rtoinfo, len))
5234                 return -EFAULT;
5235 
5236         return 0;
5237 }
5238 
5239 /*
5240  *
5241  * 7.1.2 SCTP_ASSOCINFO
5242  *
5243  * This option is used to tune the maximum retransmission attempts
5244  * of the association.
5245  * Returns an error if the new association retransmission value is
5246  * greater than the sum of the retransmission value  of the peer.
5247  * See [SCTP] for more information.
5248  *
5249  */
5250 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
5251                                      char __user *optval,
5252                                      int __user *optlen)
5253 {
5254 
5255         struct sctp_assocparams assocparams;
5256         struct sctp_association *asoc;
5257         struct list_head *pos;
5258         int cnt = 0;
5259 
5260         if (len < sizeof (struct sctp_assocparams))
5261                 return -EINVAL;
5262 
5263         len = sizeof(struct sctp_assocparams);
5264 
5265         if (copy_from_user(&assocparams, optval, len))
5266                 return -EFAULT;
5267 
5268         asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
5269 
5270         if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
5271                 return -EINVAL;
5272 
5273         /* Values correspoinding to the specific association */
5274         if (asoc) {
5275                 assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
5276                 assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
5277                 assocparams.sasoc_local_rwnd = asoc->a_rwnd;
5278                 assocparams.sasoc_cookie_life = ktime_to_ms(asoc->cookie_life);
5279 
5280                 list_for_each(pos, &asoc->peer.transport_addr_list) {
5281                         cnt++;
5282                 }
5283 
5284                 assocparams.sasoc_number_peer_destinations = cnt;
5285         } else {
5286                 /* Values corresponding to the endpoint */
5287                 struct sctp_sock *sp = sctp_sk(sk);
5288 
5289                 assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
5290                 assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
5291                 assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
5292                 assocparams.sasoc_cookie_life =
5293                                         sp->assocparams.sasoc_cookie_life;
5294                 assocparams.sasoc_number_peer_destinations =
5295                                         sp->assocparams.
5296                                         sasoc_number_peer_destinations;
5297         }
5298 
5299         if (put_user(len, optlen))
5300                 return -EFAULT;
5301 
5302         if (copy_to_user(optval, &assocparams, len))
5303                 return -EFAULT;
5304 
5305         return 0;
5306 }
5307 
5308 /*
5309  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
5310  *
5311  * This socket option is a boolean flag which turns on or off mapped V4
5312  * addresses.  If this option is turned on and the socket is type
5313  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
5314  * If this option is turned off, then no mapping will be done of V4
5315  * addresses and a user will receive both PF_INET6 and PF_INET type
5316  * addresses on the socket.
5317  */
5318 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
5319                                     char __user *optval, int __user *optlen)
5320 {
5321         int val;
5322         struct sctp_sock *sp = sctp_sk(sk);
5323 
5324         if (len < sizeof(int))
5325                 return -EINVAL;
5326 
5327         len = sizeof(int);
5328         val = sp->v4mapped;
5329         if (put_user(len, optlen))
5330                 return -EFAULT;
5331         if (copy_to_user(optval, &val, len))
5332                 return -EFAULT;
5333 
5334         return 0;
5335 }
5336 
5337 /*
5338  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
5339  * (chapter and verse is quoted at sctp_setsockopt_context())
5340  */
5341 static int sctp_getsockopt_context(struct sock *sk, int len,
5342                                    char __user *optval, int __user *optlen)
5343 {
5344         struct sctp_assoc_value params;
5345         struct sctp_sock *sp;
5346         struct sctp_association *asoc;
5347 
5348         if (len < sizeof(struct sctp_assoc_value))
5349                 return -EINVAL;
5350 
5351         len = sizeof(struct sctp_assoc_value);
5352 
5353         if (copy_from_user(&params, optval, len))
5354                 return -EFAULT;
5355 
5356         sp = sctp_sk(sk);
5357 
5358         if (params.assoc_id != 0) {
5359                 asoc = sctp_id2assoc(sk, params.assoc_id);
5360                 if (!asoc)
5361                         return -EINVAL;
5362                 params.assoc_value = asoc->default_rcv_context;
5363         } else {
5364                 params.assoc_value = sp->default_rcv_context;
5365         }
5366 
5367         if (put_user(len, optlen))
5368                 return -EFAULT;
5369         if (copy_to_user(optval, &params, len))
5370                 return -EFAULT;
5371 
5372         return 0;
5373 }
5374 
5375 /*
5376  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
5377  * This option will get or set the maximum size to put in any outgoing
5378  * SCTP DATA chunk.  If a message is larger than this size it will be
5379  * fragmented by SCTP into the specified size.  Note that the underlying
5380  * SCTP implementation may fragment into smaller sized chunks when the
5381  * PMTU of the underlying association is smaller than the value set by
5382  * the user.  The default value for this option is '' which indicates
5383  * the user is NOT limiting fragmentation and only the PMTU will effect
5384  * SCTP's choice of DATA chunk size.  Note also that values set larger
5385  * than the maximum size of an IP datagram will effectively let SCTP
5386  * control fragmentation (i.e. the same as setting this option to 0).
5387  *
5388  * The following structure is used to access and modify this parameter:
5389  *
5390  * struct sctp_assoc_value {
5391  *   sctp_assoc_t assoc_id;
5392  *   uint32_t assoc_value;
5393  * };
5394  *
5395  * assoc_id:  This parameter is ignored for one-to-one style sockets.
5396  *    For one-to-many style sockets this parameter indicates which
5397  *    association the user is performing an action upon.  Note that if
5398  *    this field's value is zero then the endpoints default value is
5399  *    changed (effecting future associations only).
5400  * assoc_value:  This parameter specifies the maximum size in bytes.
5401  */
5402 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
5403                                   char __user *optval, int __user *optlen)
5404 {
5405         struct sctp_assoc_value params;
5406         struct sctp_association *asoc;
5407 
5408         if (len == sizeof(int)) {
5409                 pr_warn_ratelimited(DEPRECATED
5410                                     "%s (pid %d) "
5411                                     "Use of int in maxseg socket option.\n"
5412                                     "Use struct sctp_assoc_value instead\n",
5413                                     current->comm, task_pid_nr(current));
5414                 params.assoc_id = 0;
5415         } else if (len >= sizeof(struct sctp_assoc_value)) {
5416                 len = sizeof(struct sctp_assoc_value);
5417                 if (copy_from_user(&params, optval, sizeof(params)))
5418                         return -EFAULT;
5419         } else
5420                 return -EINVAL;
5421 
5422         asoc = sctp_id2assoc(sk, params.assoc_id);
5423         if (!asoc && params.assoc_id && sctp_style(sk, UDP))
5424                 return -EINVAL;
5425 
5426         if (asoc)
5427                 params.assoc_value = asoc->frag_point;
5428         else
5429                 params.assoc_value = sctp_sk(sk)->user_frag;
5430 
5431         if (put_user(len, optlen))
5432                 return -EFAULT;
5433         if (len == sizeof(int)) {
5434                 if (copy_to_user(optval, &params.assoc_value, len))
5435                         return -EFAULT;
5436         } else {
5437                 if (copy_to_user(optval, &params, len))
5438                         return -EFAULT;
5439         }
5440 
5441         return 0;
5442 }
5443 
5444 /*
5445  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
5446  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
5447  */
5448 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
5449                                                char __user *optval, int __user *optlen)
5450 {
5451         int val;
5452 
5453         if (len < sizeof(int))
5454                 return -EINVAL;
5455 
5456         len = sizeof(int);
5457 
5458         val = sctp_sk(sk)->frag_interleave;
5459         if (put_user(len, optlen))
5460                 return -EFAULT;
5461         if (copy_to_user(optval, &val, len))
5462                 return -EFAULT;
5463 
5464         return 0;
5465 }
5466 
5467 /*
5468  * 7.1.25.  Set or Get the sctp partial delivery point
5469  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
5470  */
5471 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
5472                                                   char __user *optval,
5473                                                   int __user *optlen)
5474 {
5475         u32 val;
5476 
5477         if (len < sizeof(u32))
5478                 return -EINVAL;
5479 
5480         len = sizeof(u32);
5481 
5482         val = sctp_sk(sk)->pd_point;
5483         if (put_user(len, optlen))
5484                 return -EFAULT;
5485         if (copy_to_user(optval, &val, len))
5486                 return -EFAULT;
5487 
5488         return 0;
5489 }
5490 
5491 /*
5492  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
5493  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
5494  */
5495 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
5496                                     char __user *optval,
5497                                     int __user *optlen)
5498 {
5499         struct sctp_assoc_value params;
5500         struct sctp_sock *sp;
5501         struct sctp_association *asoc;
5502 
5503         if (len == sizeof(int)) {
5504                 pr_warn_ratelimited(DEPRECATED
5505                                     "%s (pid %d) "
5506                                     "Use of int in max_burst socket option.\n"
5507                                     "Use struct sctp_assoc_value instead\n",
5508                                     current->comm, task_pid_nr(current));
5509                 params.assoc_id = 0;
5510         } else if (len >= sizeof(struct sctp_assoc_value)) {
5511                 len = sizeof(struct sctp_assoc_value);
5512                 if (copy_from_user(&params, optval, len))
5513                         return -EFAULT;
5514         } else
5515                 return -EINVAL;
5516 
5517         sp = sctp_sk(sk);
5518 
5519         if (params.assoc_id != 0) {
5520                 asoc = sctp_id2assoc(sk, params.assoc_id);
5521                 if (!asoc)
5522                         return -EINVAL;
5523                 params.assoc_value = asoc->max_burst;
5524         } else
5525                 params.assoc_value = sp->max_burst;
5526 
5527         if (len == sizeof(int)) {
5528                 if (copy_to_user(optval, &params.assoc_value, len))
5529                         return -EFAULT;
5530         } else {
5531                 if (copy_to_user(optval, &params, len))
5532                         return -EFAULT;
5533         }
5534 
5535         return 0;
5536 
5537 }
5538 
5539 static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
5540                                     char __user *optval, int __user *optlen)
5541 {
5542         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5543         struct sctp_hmacalgo  __user *p = (void __user *)optval;
5544         struct sctp_hmac_algo_param *hmacs;
5545         __u16 data_len = 0;
5546         u32 num_idents;
5547 
5548         if (!ep->auth_enable)
5549                 return -EACCES;
5550 
5551         hmacs = ep->auth_hmacs_list;
5552         data_len = ntohs(hmacs->param_hdr.length) - sizeof(sctp_paramhdr_t);
5553 
5554         if (len < sizeof(struct sctp_hmacalgo) + data_len)
5555                 return -EINVAL;
5556 
5557         len = sizeof(struct sctp_hmacalgo) + data_len;
5558         num_idents = data_len / sizeof(u16);
5559 
5560         if (put_user(len, optlen))
5561                 return -EFAULT;
5562         if (put_user(num_idents, &p->shmac_num_idents))
5563                 return -EFAULT;
5564         if (copy_to_user(p->shmac_idents, hmacs->hmac_ids, data_len))
5565                 return -EFAULT;
5566         return 0;
5567 }
5568 
5569 static int sctp_getsockopt_active_key(struct sock *sk, int len,
5570                                     char __user *optval, int __user *optlen)
5571 {
5572         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5573         struct sctp_authkeyid val;
5574         struct sctp_association *asoc;
5575 
5576         if (!ep->auth_enable)
5577                 return -EACCES;
5578 
5579         if (len < sizeof(struct sctp_authkeyid))
5580                 return -EINVAL;
5581         if (copy_from_user(&val, optval, sizeof(struct sctp_authkeyid)))
5582                 return -EFAULT;
5583 
5584         asoc = sctp_id2assoc(sk, val.scact_assoc_id);
5585         if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
5586                 return -EINVAL;
5587 
5588         if (asoc)
5589                 val.scact_keynumber = asoc->active_key_id;
5590         else
5591                 val.scact_keynumber = ep->active_key_id;
5592 
5593         len = sizeof(struct sctp_authkeyid);
5594         if (put_user(len, optlen))
5595                 return -EFAULT;
5596         if (copy_to_user(optval, &val, len))
5597                 return -EFAULT;
5598 
5599         return 0;
5600 }
5601 
5602 static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
5603                                     char __user *optval, int __user *optlen)
5604 {
5605         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5606         struct sctp_authchunks __user *p = (void __user *)optval;
5607         struct sctp_authchunks val;
5608         struct sctp_association *asoc;
5609         struct sctp_chunks_param *ch;
5610         u32    num_chunks = 0;
5611         char __user *to;
5612 
5613         if (!ep->auth_enable)
5614                 return -EACCES;
5615 
5616         if (len < sizeof(struct sctp_authchunks))
5617                 return -EINVAL;
5618 
5619         if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5620                 return -EFAULT;
5621 
5622         to = p->gauth_chunks;
5623         asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5624         if (!asoc)
5625                 return -EINVAL;
5626 
5627         ch = asoc->peer.peer_chunks;
5628         if (!ch)
5629                 goto num;
5630 
5631         /* See if the user provided enough room for all the data */
5632         num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5633         if (len < num_chunks)
5634                 return -EINVAL;
5635 
5636         if (copy_to_user(to, ch->chunks, num_chunks))
5637                 return -EFAULT;
5638 num:
5639         len = sizeof(struct sctp_authchunks) + num_chunks;
5640         if (put_user(len, optlen))
5641                 return -EFAULT;
5642         if (put_user(num_chunks, &p->gauth_number_of_chunks))
5643                 return -EFAULT;
5644         return 0;
5645 }
5646 
5647 static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
5648                                     char __user *optval, int __user *optlen)
5649 {
5650         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5651         struct sctp_authchunks __user *p = (void __user *)optval;
5652         struct sctp_authchunks val;
5653         struct sctp_association *asoc;
5654         struct sctp_chunks_param *ch;
5655         u32    num_chunks = 0;
5656         char __user *to;
5657 
5658         if (!ep->auth_enable)
5659                 return -EACCES;
5660 
5661         if (len < sizeof(struct sctp_authchunks))
5662                 return -EINVAL;
5663 
5664         if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5665                 return -EFAULT;
5666 
5667         to = p->gauth_chunks;
5668         asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5669         if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
5670                 return -EINVAL;
5671 
5672         if (asoc)
5673                 ch = (struct sctp_chunks_param *)asoc->c.auth_chunks;
5674         else
5675                 ch = ep->auth_chunk_list;
5676 
5677         if (!ch)
5678                 goto num;
5679 
5680         num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5681         if (len < sizeof(struct sctp_authchunks) + num_chunks)
5682                 return -EINVAL;
5683 
5684         if (copy_to_user(to, ch->chunks, num_chunks))
5685                 return -EFAULT;
5686 num:
5687         len = sizeof(struct sctp_authchunks) + num_chunks;
5688         if (put_user(len, optlen))
5689                 return -EFAULT;
5690         if (put_user(num_chunks, &p->gauth_number_of_chunks))
5691                 return -EFAULT;
5692 
5693         return 0;
5694 }
5695 
5696 /*
5697  * 8.2.5.  Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)
5698  * This option gets the current number of associations that are attached
5699  * to a one-to-many style socket.  The option value is an uint32_t.
5700  */
5701 static int sctp_getsockopt_assoc_number(struct sock *sk, int len,
5702                                     char __user *optval, int __user *optlen)
5703 {
5704         struct sctp_sock *sp = sctp_sk(sk);
5705         struct sctp_association *asoc;
5706         u32 val = 0;
5707 
5708         if (sctp_style(sk, TCP))
5709                 return -EOPNOTSUPP;
5710 
5711         if (len < sizeof(u32))
5712                 return -EINVAL;
5713 
5714         len = sizeof(u32);
5715 
5716         list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
5717                 val++;
5718         }
5719 
5720         if (put_user(len, optlen))
5721                 return -EFAULT;
5722         if (copy_to_user(optval, &val, len))
5723                 return -EFAULT;
5724 
5725         return 0;
5726 }
5727 
5728 /*
5729  * 8.1.23 SCTP_AUTO_ASCONF
5730  * See the corresponding setsockopt entry as description
5731  */
5732 static int sctp_getsockopt_auto_asconf(struct sock *sk, int len,
5733                                    char __user *optval, int __user *optlen)
5734 {
5735         int val = 0;
5736 
5737         if (len < sizeof(int))
5738                 return -EINVAL;
5739 
5740         len = sizeof(int);
5741         if (sctp_sk(sk)->do_auto_asconf && sctp_is_ep_boundall(sk))
5742                 val = 1;
5743         if (put_user(len, optlen))
5744                 return -EFAULT;
5745         if (copy_to_user(optval, &val, len))
5746                 return -EFAULT;
5747         return 0;
5748 }
5749 
5750 /*
5751  * 8.2.6. Get the Current Identifiers of Associations
5752  *        (SCTP_GET_ASSOC_ID_LIST)
5753  *
5754  * This option gets the current list of SCTP association identifiers of
5755  * the SCTP associations handled by a one-to-many style socket.
5756  */
5757 static int sctp_getsockopt_assoc_ids(struct sock *sk, int len,
5758                                     char __user *optval, int __user *optlen)
5759 {
5760         struct sctp_sock *sp = sctp_sk(sk);
5761         struct sctp_association *asoc;
5762         struct sctp_assoc_ids *ids;
5763         u32 num = 0;
5764 
5765         if (sctp_style(sk, TCP))
5766                 return -EOPNOTSUPP;
5767 
5768         if (len < sizeof(struct sctp_assoc_ids))
5769                 return -EINVAL;
5770 
5771         list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
5772                 num++;
5773         }
5774 
5775         if (len < sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num)
5776                 return -EINVAL;
5777 
5778         len = sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num;
5779 
5780         ids = kmalloc(len, GFP_KERNEL);
5781         if (unlikely(!ids))
5782                 return -ENOMEM;
5783 
5784         ids->gaids_number_of_ids = num;
5785         num = 0;
5786         list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
5787                 ids->gaids_assoc_id[num++] = asoc->assoc_id;
5788         }
5789 
5790         if (put_user(len, optlen) || copy_to_user(optval, ids, len)) {
5791                 kfree(ids);
5792                 return -EFAULT;
5793         }
5794 
5795         kfree(ids);
5796         return 0;
5797 }
5798 
5799 /*
5800  * SCTP_PEER_ADDR_THLDS
5801  *
5802  * This option allows us to fetch the partially failed threshold for one or all
5803  * transports in an association.  See Section 6.1 of:
5804  * http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt
5805  */
5806 static int sctp_getsockopt_paddr_thresholds(struct sock *sk,
5807                                             char __user *optval,
5808                                             int len,
5809                                             int __user *optlen)
5810 {
5811         struct sctp_paddrthlds val;
5812         struct sctp_transport *trans;
5813         struct sctp_association *asoc;
5814 
5815         if (len < sizeof(struct sctp_paddrthlds))
5816                 return -EINVAL;
5817         len = sizeof(struct sctp_paddrthlds);
5818         if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval, len))
5819                 return -EFAULT;
5820 
5821         if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
5822                 asoc = sctp_id2assoc(sk, val.spt_assoc_id);
5823                 if (!asoc)
5824                         return -ENOENT;
5825 
5826                 val.spt_pathpfthld = asoc->pf_retrans;
5827                 val.spt_pathmaxrxt = asoc->pathmaxrxt;
5828         } else {
5829                 trans = sctp_addr_id2transport(sk, &val.spt_address,
5830                                                val.spt_assoc_id);
5831                 if (!trans)
5832                         return -ENOENT;
5833 
5834                 val.spt_pathmaxrxt = trans->pathmaxrxt;
5835                 val.spt_pathpfthld = trans->pf_retrans;
5836         }
5837 
5838         if (put_user(len, optlen) || copy_to_user(optval, &val, len))
5839                 return -EFAULT;
5840 
5841         return 0;
5842 }
5843 
5844 /*
5845  * SCTP_GET_ASSOC_STATS
5846  *
5847  * This option retrieves local per endpoint statistics. It is modeled
5848  * after OpenSolaris' implementation
5849  */
5850 static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
5851                                        char __user *optval,
5852                                        int __user *optlen)
5853 {
5854         struct sctp_assoc_stats sas;
5855         struct sctp_association *asoc = NULL;
5856 
5857         /* User must provide at least the assoc id */
5858         if (len < sizeof(sctp_assoc_t))
5859                 return -EINVAL;
5860 
5861         /* Allow the struct to grow and fill in as much as possible */
5862         len = min_t(size_t, len, sizeof(sas));
5863 
5864         if (copy_from_user(&sas, optval, len))
5865                 return -EFAULT;
5866 
5867         asoc = sctp_id2assoc(sk, sas.sas_assoc_id);
5868         if (!asoc)
5869                 return -EINVAL;
5870 
5871         sas.sas_rtxchunks = asoc->stats.rtxchunks;
5872         sas.sas_gapcnt = asoc->stats.gapcnt;
5873         sas.sas_outofseqtsns = asoc->stats.outofseqtsns;
5874         sas.sas_osacks = asoc->stats.osacks;
5875         sas.sas_isacks = asoc->stats.isacks;
5876         sas.sas_octrlchunks = asoc->stats.octrlchunks;
5877         sas.sas_ictrlchunks = asoc->stats.ictrlchunks;
5878         sas.sas_oodchunks = asoc->stats.oodchunks;
5879         sas.sas_iodchunks = asoc->stats.iodchunks;
5880         sas.sas_ouodchunks = asoc->stats.ouodchunks;
5881         sas.sas_iuodchunks = asoc->stats.iuodchunks;
5882         sas.sas_idupchunks = asoc->stats.idupchunks;
5883         sas.sas_opackets = asoc->stats.opackets;
5884         sas.sas_ipackets = asoc->stats.ipackets;
5885 
5886         /* New high max rto observed, will return 0 if not a single
5887          * RTO update took place. obs_rto_ipaddr will be bogus
5888          * in such a case
5889          */
5890         sas.sas_maxrto = asoc->stats.max_obs_rto;
5891         memcpy(&sas.sas_obs_rto_ipaddr, &asoc->stats.obs_rto_ipaddr,
5892                 sizeof(struct sockaddr_storage));
5893 
5894         /* Mark beginning of a new observation period */
5895         asoc->stats.max_obs_rto = asoc->rto_min;
5896 
5897         if (put_user(len, optlen))
5898                 return -EFAULT;
5899 
5900         pr_debug("%s: len:%d, assoc_id:%d\n", __func__, len, sas.sas_assoc_id);
5901 
5902         if (copy_to_user(optval, &sas, len))
5903                 return -EFAULT;
5904 
5905         return 0;
5906 }
5907 
5908 static int sctp_getsockopt_recvrcvinfo(struct sock *sk, int len,
5909                                        char __user *optval,
5910                                        int __user *optlen)
5911 {
5912         int val = 0;
5913 
5914         if (len < sizeof(int))
5915                 return -EINVAL;
5916 
5917         len = sizeof(int);
5918         if (sctp_sk(sk)->recvrcvinfo)
5919                 val = 1;
5920         if (put_user(len, optlen))
5921                 return -EFAULT;
5922         if (copy_to_user(optval, &val, len))
5923                 return -EFAULT;
5924 
5925         return 0;
5926 }
5927 
5928 static int sctp_getsockopt_recvnxtinfo(struct sock *sk, int len,
5929                                        char __user *optval,
5930                                        int __user *optlen)
5931 {
5932         int val = 0;
5933 
5934         if (len < sizeof(int))
5935                 return -EINVAL;
5936 
5937         len = sizeof(int);
5938         if (sctp_sk(sk)->recvnxtinfo)
5939                 val = 1;
5940         if (put_user(len, optlen))
5941                 return -EFAULT;
5942         if (copy_to_user(optval, &val, len))
5943                 return -EFAULT;
5944 
5945         return 0;
5946 }
5947 
5948 static int sctp_getsockopt(struct sock *sk, int level, int optname,
5949                            char __user *optval, int __user *optlen)
5950 {
5951         int retval = 0;
5952         int len;
5953 
5954         pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname);
5955 
5956         /* I can hardly begin to describe how wrong this is.  This is
5957          * so broken as to be worse than useless.  The API draft
5958          * REALLY is NOT helpful here...  I am not convinced that the
5959          * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
5960          * are at all well-founded.
5961          */
5962         if (level != SOL_SCTP) {
5963                 struct sctp_af *af = sctp_sk(sk)->pf->af;
5964 
5965                 retval = af->getsockopt(sk, level, optname, optval, optlen);
5966                 return retval;
5967         }
5968 
5969         if (get_user(len, optlen))
5970                 return -EFAULT;
5971 
5972         lock_sock(sk);
5973 
5974         switch (optname) {
5975         case SCTP_STATUS:
5976                 retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
5977                 break;
5978         case SCTP_DISABLE_FRAGMENTS:
5979                 retval = sctp_getsockopt_disable_fragments(sk, len, optval,
5980                                                            optlen);
5981                 break;
5982         case SCTP_EVENTS:
5983                 retval = sctp_getsockopt_events(sk, len, optval, optlen);
5984                 break;
5985         case SCTP_AUTOCLOSE:
5986                 retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
5987                 break;
5988         case SCTP_SOCKOPT_PEELOFF:
5989                 retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
5990                 break;
5991         case SCTP_PEER_ADDR_PARAMS:
5992                 retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
5993                                                           optlen);
5994                 break;
5995         case SCTP_DELAYED_SACK:
5996                 retval = sctp_getsockopt_delayed_ack(sk, len, optval,
5997                                                           optlen);
5998                 break;
5999         case SCTP_INITMSG:
6000                 retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
6001                 break;
6002         case SCTP_GET_PEER_ADDRS:
6003                 retval = sctp_getsockopt_peer_addrs(sk, len, optval,
6004                                                     optlen);
6005                 break;
6006         case SCTP_GET_LOCAL_ADDRS:
6007                 retval = sctp_getsockopt_local_addrs(sk, len, optval,
6008                                                      optlen);
6009                 break;
6010         case SCTP_SOCKOPT_CONNECTX3:
6011                 retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
6012                 break;
6013         case SCTP_DEFAULT_SEND_PARAM:
6014                 retval = sctp_getsockopt_default_send_param(sk, len,
6015                                                             optval, optlen);
6016                 break;
6017         case SCTP_DEFAULT_SNDINFO:
6018                 retval = sctp_getsockopt_default_sndinfo(sk, len,
6019                                                          optval, optlen);
6020                 break;
6021         case SCTP_PRIMARY_ADDR:
6022                 retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
6023                 break;
6024         case SCTP_NODELAY:
6025                 retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
6026                 break;
6027         case SCTP_RTOINFO:
6028                 retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
6029                 break;
6030         case SCTP_ASSOCINFO:
6031                 retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
6032                 break;
6033         case SCTP_I_WANT_MAPPED_V4_ADDR:
6034                 retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
6035                 break;
6036         case SCTP_MAXSEG:
6037                 retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
6038                 break;
6039         case SCTP_GET_PEER_ADDR_INFO:
6040                 retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
6041                                                         optlen);
6042                 break;
6043         case SCTP_ADAPTATION_LAYER:
6044                 retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
6045                                                         optlen);
6046                 break;
6047         case SCTP_CONTEXT:
6048                 retval = sctp_getsockopt_context(sk, len, optval, optlen);
6049                 break;
6050         case SCTP_FRAGMENT_INTERLEAVE:
6051                 retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
6052                                                              optlen);
6053                 break;
6054         case SCTP_PARTIAL_DELIVERY_POINT:
6055                 retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
6056                                                                 optlen);
6057                 break;
6058         case SCTP_MAX_BURST:
6059                 retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
6060                 break;
6061         case SCTP_AUTH_KEY:
6062         case SCTP_AUTH_CHUNK:
6063         case SCTP_AUTH_DELETE_KEY:
6064                 retval = -EOPNOTSUPP;
6065                 break;
6066         case SCTP_HMAC_IDENT:
6067                 retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
6068                 break;
6069         case SCTP_AUTH_ACTIVE_KEY:
6070                 retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
6071                 break;
6072         case SCTP_PEER_AUTH_CHUNKS:
6073                 retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
6074                                                         optlen);
6075                 break;
6076         case SCTP_LOCAL_AUTH_CHUNKS:
6077                 retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
6078                                                         optlen);
6079                 break;
6080         case SCTP_GET_ASSOC_NUMBER:
6081                 retval = sctp_getsockopt_assoc_number(sk, len, optval, optlen);
6082                 break;
6083         case SCTP_GET_ASSOC_ID_LIST:
6084                 retval = sctp_getsockopt_assoc_ids(sk, len, optval, optlen);
6085                 break;
6086         case SCTP_AUTO_ASCONF:
6087                 retval = sctp_getsockopt_auto_asconf(sk, len, optval, optlen);
6088                 break;
6089         case SCTP_PEER_ADDR_THLDS:
6090                 retval = sctp_getsockopt_paddr_thresholds(sk, optval, len, optlen);
6091                 break;
6092         case SCTP_GET_ASSOC_STATS:
6093                 retval = sctp_getsockopt_assoc_stats(sk, len, optval, optlen);
6094                 break;
6095         case SCTP_RECVRCVINFO:
6096                 retval = sctp_getsockopt_recvrcvinfo(sk, len, optval, optlen);
6097                 break;
6098         case SCTP_RECVNXTINFO:
6099                 retval = sctp_getsockopt_recvnxtinfo(sk, len, optval, optlen);
6100                 break;
6101         default:
6102                 retval = -ENOPROTOOPT;
6103                 break;
6104         }
6105 
6106         release_sock(sk);
6107         return retval;
6108 }
6109 
6110 static void sctp_hash(struct sock *sk)
6111 {
6112         /* STUB */
6113 }
6114 
6115 static void sctp_unhash(struct sock *sk)
6116 {
6117         /* STUB */
6118 }
6119 
6120 /* Check if port is acceptable.  Possibly find first available port.
6121  *
6122  * The port hash table (contained in the 'global' SCTP protocol storage
6123  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
6124  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
6125  * list (the list number is the port number hashed out, so as you
6126  * would expect from a hash function, all the ports in a given list have
6127  * such a number that hashes out to the same list number; you were
6128  * expecting that, right?); so each list has a set of ports, with a
6129  * link to the socket (struct sock) that uses it, the port number and
6130  * a fastreuse flag (FIXME: NPI ipg).
6131  */
6132 static struct sctp_bind_bucket *sctp_bucket_create(
6133         struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);
6134 
6135 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
6136 {
6137         struct sctp_bind_hashbucket *head; /* hash list */
6138         struct sctp_bind_bucket *pp;
6139         unsigned short snum;
6140         int ret;
6141 
6142         snum = ntohs(addr->v4.sin_port);
6143 
6144         pr_debug("%s: begins, snum:%d\n", __func__, snum);
6145 
6146         local_bh_disable();
6147 
6148         if (snum == 0) {
6149                 /* Search for an available port. */
6150                 int low, high, remaining, index;
6151                 unsigned int rover;
6152                 struct net *net = sock_net(sk);
6153 
6154                 inet_get_local_port_range(net, &low, &high);
6155                 remaining = (high - low) + 1;
6156                 rover = prandom_u32() % remaining + low;
6157 
6158                 do {
6159                         rover++;
6160                         if ((rover < low) || (rover > high))
6161                                 rover = low;
6162                         if (inet_is_local_reserved_port(net, rover))
6163                                 continue;
6164                         index = sctp_phashfn(sock_net(sk), rover);
6165                         head = &sctp_port_hashtable[index];
6166                         spin_lock(&head->lock);
6167                         sctp_for_each_hentry(pp, &head->chain)
6168                                 if ((pp->port == rover) &&
6169                                     net_eq(sock_net(sk), pp->net))
6170                                         goto next;
6171                         break;
6172                 next:
6173                         spin_unlock(&head->lock);
6174                 } while (--remaining > 0);
6175 
6176                 /* Exhausted local port range during search? */
6177                 ret = 1;
6178                 if (remaining <= 0)
6179                         goto fail;
6180 
6181                 /* OK, here is the one we will use.  HEAD (the port
6182                  * hash table list entry) is non-NULL and we hold it's
6183                  * mutex.
6184                  */
6185                 snum = rover;
6186         } else {
6187                 /* We are given an specific port number; we verify
6188                  * that it is not being used. If it is used, we will
6189                  * exahust the search in the hash list corresponding
6190                  * to the port number (snum) - we detect that with the
6191                  * port iterator, pp being NULL.
6192                  */
6193                 head = &sctp_port_hashtable[sctp_phashfn(sock_net(sk), snum)];
6194                 spin_lock(&head->lock);
6195                 sctp_for_each_hentry(pp, &head->chain) {
6196                         if ((pp->port == snum) && net_eq(pp->net, sock_net(sk)))
6197                                 goto pp_found;
6198                 }
6199         }
6200         pp = NULL;
6201         goto pp_not_found;
6202 pp_found:
6203         if (!hlist_empty(&pp->owner)) {
6204                 /* We had a port hash table hit - there is an
6205                  * available port (pp != NULL) and it is being
6206                  * used by other socket (pp->owner not empty); that other
6207                  * socket is going to be sk2.
6208                  */
6209                 int reuse = sk->sk_reuse;
6210                 struct sock *sk2;
6211 
6212                 pr_debug("%s: found a possible match\n", __func__);
6213 
6214                 if (pp->fastreuse && sk->sk_reuse &&
6215                         sk->sk_state != SCTP_SS_LISTENING)
6216                         goto success;
6217 
6218                 /* Run through the list of sockets bound to the port
6219                  * (pp->port) [via the pointers bind_next and
6220                  * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
6221                  * we get the endpoint they describe and run through
6222                  * the endpoint's list of IP (v4 or v6) addresses,
6223                  * comparing each of the addresses with the address of
6224                  * the socket sk. If we find a match, then that means
6225                  * that this port/socket (sk) combination are already
6226                  * in an endpoint.
6227                  */
6228                 sk_for_each_bound(sk2, &pp->owner) {
6229                         struct sctp_endpoint *ep2;
6230                         ep2 = sctp_sk(sk2)->ep;
6231 
6232                         if (sk == sk2 ||
6233                             (reuse && sk2->sk_reuse &&
6234                              sk2->sk_state != SCTP_SS_LISTENING))
6235                                 continue;
6236 
6237                         if (sctp_bind_addr_conflict(&ep2->base.bind_addr, addr,
6238                                                  sctp_sk(sk2), sctp_sk(sk))) {
6239                                 ret = (long)sk2;
6240                                 goto fail_unlock;
6241                         }
6242                 }
6243 
6244                 pr_debug("%s: found a match\n", __func__);
6245         }
6246 pp_not_found:
6247         /* If there was a hash table miss, create a new port.  */
6248         ret = 1;
6249         if (!pp && !(pp = sctp_bucket_create(head, sock_net(sk), snum)))
6250                 goto fail_unlock;
6251 
6252         /* In either case (hit or miss), make sure fastreuse is 1 only
6253          * if sk->sk_reuse is too (that is, if the caller requested
6254          * SO_REUSEADDR on this socket -sk-).
6255          */
6256         if (hlist_empty(&pp->owner)) {
6257                 if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
6258                         pp->fastreuse = 1;
6259                 else
6260                         pp->fastreuse = 0;
6261         } else if (pp->fastreuse &&
6262                 (!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
6263                 pp->fastreuse = 0;
6264 
6265         /* We are set, so fill up all the data in the hash table
6266          * entry, tie the socket list information with the rest of the
6267          * sockets FIXME: Blurry, NPI (ipg).
6268          */
6269 success:
6270         if (!sctp_sk(sk)->bind_hash) {
6271                 inet_sk(sk)->inet_num = snum;
6272                 sk_add_bind_node(sk, &pp->owner);
6273                 sctp_sk(sk)->bind_hash = pp;
6274         }
6275         ret = 0;
6276 
6277 fail_unlock:
6278         spin_unlock(&head->lock);
6279 
6280 fail:
6281         local_bh_enable();
6282         return ret;
6283 }
6284 
6285 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
6286  * port is requested.
6287  */
6288 static int sctp_get_port(struct sock *sk, unsigned short snum)
6289 {
6290         union sctp_addr addr;
6291         struct sctp_af *af = sctp_sk(sk)->pf->af;
6292 
6293         /* Set up a dummy address struct from the sk. */
6294         af->from_sk(&addr, sk);
6295         addr.v4.sin_port = htons(snum);
6296 
6297         /* Note: sk->sk_num gets filled in if ephemeral port request. */
6298         return !!sctp_get_port_local(sk, &addr);
6299 }
6300 
6301 /*
6302  *  Move a socket to LISTENING state.
6303  */
6304 static int sctp_listen_start(struct sock *sk, int backlog)
6305 {
6306         struct sctp_sock *sp = sctp_sk(sk);
6307         struct sctp_endpoint *ep = sp->ep;
6308         struct crypto_hash *tfm = NULL;
6309         char alg[32];
6310 
6311         /* Allocate HMAC for generating cookie. */
6312         if (!sp->hmac && sp->sctp_hmac_alg) {
6313                 sprintf(alg, "hmac(%s)", sp->sctp_hmac_alg);
6314                 tfm = crypto_alloc_hash(alg, 0, CRYPTO_ALG_ASYNC);
6315                 if (IS_ERR(tfm)) {
6316                         net_info_ratelimited("failed to load transform for %s: %ld\n",
6317                                              sp->sctp_hmac_alg, PTR_ERR(tfm));
6318                         return -ENOSYS;
6319                 }
6320                 sctp_sk(sk)->hmac = tfm;
6321         }
6322 
6323         /*
6324          * If a bind() or sctp_bindx() is not called prior to a listen()
6325          * call that allows new associations to be accepted, the system
6326          * picks an ephemeral port and will choose an address set equivalent
6327          * to binding with a wildcard address.
6328          *
6329          * This is not currently spelled out in the SCTP sockets
6330          * extensions draft, but follows the practice as seen in TCP
6331          * sockets.
6332          *
6333          */
6334         sk->sk_state = SCTP_SS_LISTENING;
6335         if (!ep->base.bind_addr.port) {
6336                 if (sctp_autobind(sk))
6337                         return -EAGAIN;
6338         } else {
6339                 if (sctp_get_port(sk, inet_sk(sk)->inet_num)) {
6340                         sk->sk_state = SCTP_SS_CLOSED;
6341                         return -EADDRINUSE;
6342                 }
6343         }
6344 
6345         sk->sk_max_ack_backlog = backlog;
6346         sctp_hash_endpoint(ep);
6347         return 0;
6348 }
6349 
6350 /*
6351  * 4.1.3 / 5.1.3 listen()
6352  *
6353  *   By default, new associations are not accepted for UDP style sockets.
6354  *   An application uses listen() to mark a socket as being able to
6355  *   accept new associations.
6356  *
6357  *   On TCP style sockets, applications use listen() to ready the SCTP
6358  *   endpoint for accepting inbound associations.
6359  *
6360  *   On both types of endpoints a backlog of '' disables listening.
6361  *
6362  *  Move a socket to LISTENING state.
6363  */
6364 int sctp_inet_listen(struct socket *sock, int backlog)
6365 {
6366         struct sock *sk = sock->sk;
6367         struct sctp_endpoint *ep = sctp_sk(sk)->ep;
6368         int err = -EINVAL;
6369 
6370         if (unlikely(backlog < 0))
6371                 return err;
6372 
6373         lock_sock(sk);
6374 
6375         /* Peeled-off sockets are not allowed to listen().  */
6376         if (sctp_style(sk, UDP_HIGH_BANDWIDTH))
6377                 goto out;
6378 
6379         if (sock->state != SS_UNCONNECTED)
6380                 goto out;
6381 
6382         /* If backlog is zero, disable listening. */
6383         if (!backlog) {
6384                 if (sctp_sstate(sk, CLOSED))
6385                         goto out;
6386 
6387                 err = 0;
6388                 sctp_unhash_endpoint(ep);
6389                 sk->sk_state = SCTP_SS_CLOSED;
6390                 if (sk->sk_reuse)
6391                         sctp_sk(sk)->bind_hash->fastreuse = 1;
6392                 goto out;
6393         }
6394 
6395         /* If we are already listening, just update the backlog */
6396         if (sctp_sstate(sk, LISTENING))
6397                 sk->sk_max_ack_backlog = backlog;
6398         else {
6399                 err = sctp_listen_start(sk, backlog);
6400                 if (err)
6401                         goto out;
6402         }
6403 
6404         err = 0;
6405 out:
6406         release_sock(sk);
6407         return err;
6408 }
6409 
6410 /*
6411  * This function is done by modeling the current datagram_poll() and the
6412  * tcp_poll().  Note that, based on these implementations, we don't
6413  * lock the socket in this function, even though it seems that,
6414  * ideally, locking or some other mechanisms can be used to ensure
6415  * the integrity of the counters (sndbuf and wmem_alloc) used
6416  * in this place.  We assume that we don't need locks either until proven
6417  * otherwise.
6418  *
6419  * Another thing to note is that we include the Async I/O support
6420  * here, again, by modeling the current TCP/UDP code.  We don't have
6421  * a good way to test with it yet.
6422  */
6423 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
6424 {
6425         struct sock *sk = sock->sk;
6426         struct sctp_sock *sp = sctp_sk(sk);
6427         unsigned int mask;
6428 
6429         poll_wait(file, sk_sleep(sk), wait);
6430 
6431         /* A TCP-style listening socket becomes readable when the accept queue
6432          * is not empty.
6433          */
6434         if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
6435                 return (!list_empty(&sp->ep->asocs)) ?
6436                         (POLLIN | POLLRDNORM) : 0;
6437 
6438         mask = 0;
6439 
6440         /* Is there any exceptional events?  */
6441         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
6442                 mask |= POLLERR |
6443                         (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0);
6444         if (sk->sk_shutdown & RCV_SHUTDOWN)
6445                 mask |= POLLRDHUP | POLLIN | POLLRDNORM;
6446         if (sk->sk_shutdown == SHUTDOWN_MASK)
6447                 mask |= POLLHUP;
6448 
6449         /* Is it readable?  Reconsider this code with TCP-style support.  */
6450         if (!skb_queue_empty(&sk->sk_receive_queue))
6451                 mask |= POLLIN | POLLRDNORM;
6452 
6453         /* The association is either gone or not ready.  */
6454         if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
6455                 return mask;
6456 
6457         /* Is it writable?  */
6458         if (sctp_writeable(sk)) {
6459                 mask |= POLLOUT | POLLWRNORM;
6460         } else {
6461                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
6462                 /*
6463                  * Since the socket is not locked, the buffer
6464                  * might be made available after the writeable check and
6465                  * before the bit is set.  This could cause a lost I/O
6466                  * signal.  tcp_poll() has a race breaker for this race
6467                  * condition.  Based on their implementation, we put
6468                  * in the following code to cover it as well.
6469                  */
6470                 if (sctp_writeable(sk))
6471                         mask |= POLLOUT | POLLWRNORM;
6472         }
6473         return mask;
6474 }
6475 
6476 /********************************************************************
6477  * 2nd Level Abstractions
6478  ********************************************************************/
6479 
6480 static struct sctp_bind_bucket *sctp_bucket_create(
6481         struct sctp_bind_hashbucket *head, struct net *net, unsigned short snum)
6482 {
6483         struct sctp_bind_bucket *pp;
6484 
6485         pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
6486         if (pp) {
6487                 SCTP_DBG_OBJCNT_INC(bind_bucket);
6488                 pp->port = snum;
6489                 pp->fastreuse = 0;
6490                 INIT_HLIST_HEAD(&pp->owner);
6491                 pp->net = net;
6492                 hlist_add_head(&pp->node, &head->chain);
6493         }
6494         return pp;
6495 }
6496 
6497 /* Caller must hold hashbucket lock for this tb with local BH disabled */
6498 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
6499 {
6500         if (pp && hlist_empty(&pp->owner)) {
6501                 __hlist_del(&pp->node);
6502                 kmem_cache_free(sctp_bucket_cachep, pp);
6503                 SCTP_DBG_OBJCNT_DEC(bind_bucket);
6504         }
6505 }
6506 
6507 /* Release this socket's reference to a local port.  */
6508 static inline void __sctp_put_port(struct sock *sk)
6509 {
6510         struct sctp_bind_hashbucket *head =
6511                 &sctp_port_hashtable[sctp_phashfn(sock_net(sk),
6512                                                   inet_sk(sk)->inet_num)];
6513         struct sctp_bind_bucket *pp;
6514 
6515         spin_lock(&head->lock);
6516         pp = sctp_sk(sk)->bind_hash;
6517         __sk_del_bind_node(sk);
6518         sctp_sk(sk)->bind_hash = NULL;
6519         inet_sk(sk)->inet_num = 0;
6520         sctp_bucket_destroy(pp);
6521         spin_unlock(&head->lock);
6522 }
6523 
6524 void sctp_put_port(struct sock *sk)
6525 {
6526         local_bh_disable();
6527         __sctp_put_port(sk);
6528         local_bh_enable();
6529 }
6530 
6531 /*
6532  * The system picks an ephemeral port and choose an address set equivalent
6533  * to binding with a wildcard address.
6534  * One of those addresses will be the primary address for the association.
6535  * This automatically enables the multihoming capability of SCTP.
6536  */
6537 static int sctp_autobind(struct sock *sk)
6538 {
6539         union sctp_addr autoaddr;
6540         struct sctp_af *af;
6541         __be16 port;
6542 
6543         /* Initialize a local sockaddr structure to INADDR_ANY. */
6544         af = sctp_sk(sk)->pf->af;
6545 
6546         port = htons(inet_sk(sk)->inet_num);
6547         af->inaddr_any(&autoaddr, port);
6548 
6549         return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
6550 }
6551 
6552 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
6553  *
6554  * From RFC 2292
6555  * 4.2 The cmsghdr Structure *
6556  *
6557  * When ancillary data is sent or received, any number of ancillary data
6558  * objects can be specified by the msg_control and msg_controllen members of
6559  * the msghdr structure, because each object is preceded by
6560  * a cmsghdr structure defining the object's length (the cmsg_len member).
6561  * Historically Berkeley-derived implementations have passed only one object
6562  * at a time, but this API allows multiple objects to be
6563  * passed in a single call to sendmsg() or recvmsg(). The following example
6564  * shows two ancillary data objects in a control buffer.
6565  *
6566  *   |<--------------------------- msg_controllen -------------------------->|
6567  *   |                                                                       |
6568  *
6569  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
6570  *
6571  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
6572  *   |                                   |                                   |
6573  *
6574  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
6575  *
6576  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
6577  *   |                                |  |                                |  |
6578  *
6579  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
6580  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
6581  *
6582  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
6583  *
6584  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
6585  *    ^
6586  *    |
6587  *
6588  * msg_control
6589  * points here
6590  */
6591 static int sctp_msghdr_parse(const struct msghdr *msg, sctp_cmsgs_t *cmsgs)
6592 {
6593         struct cmsghdr *cmsg;
6594         struct msghdr *my_msg = (struct msghdr *)msg;
6595 
6596         for_each_cmsghdr(cmsg, my_msg) {
6597                 if (!CMSG_OK(my_msg, cmsg))
6598                         return -EINVAL;
6599 
6600                 /* Should we parse this header or ignore?  */
6601                 if (cmsg->cmsg_level != IPPROTO_SCTP)
6602                         continue;
6603 
6604                 /* Strictly check lengths following example in SCM code.  */
6605                 switch (cmsg->cmsg_type) {
6606                 case SCTP_INIT:
6607                         /* SCTP Socket API Extension
6608                          * 5.3.1 SCTP Initiation Structure (SCTP_INIT)
6609                          *
6610                          * This cmsghdr structure provides information for
6611                          * initializing new SCTP associations with sendmsg().
6612                          * The SCTP_INITMSG socket option uses this same data
6613                          * structure.  This structure is not used for
6614                          * recvmsg().
6615                          *
6616                          * cmsg_level    cmsg_type      cmsg_data[]
6617                          * ------------  ------------   ----------------------
6618                          * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
6619                          */
6620                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_initmsg)))
6621                                 return -EINVAL;
6622 
6623                         cmsgs->init = CMSG_DATA(cmsg);
6624                         break;
6625 
6626                 case SCTP_SNDRCV:
6627                         /* SCTP Socket API Extension
6628                          * 5.3.2 SCTP Header Information Structure(SCTP_SNDRCV)
6629                          *
6630                          * This cmsghdr structure specifies SCTP options for
6631                          * sendmsg() and describes SCTP header information
6632                          * about a received message through recvmsg().
6633                          *
6634                          * cmsg_level    cmsg_type      cmsg_data[]
6635                          * ------------  ------------   ----------------------
6636                          * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
6637                          */
6638                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
6639                                 return -EINVAL;
6640 
6641                         cmsgs->srinfo = CMSG_DATA(cmsg);
6642 
6643                         if (cmsgs->srinfo->sinfo_flags &
6644                             ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
6645                               SCTP_ABORT | SCTP_EOF))
6646                                 return -EINVAL;
6647                         break;
6648 
6649                 case SCTP_SNDINFO:
6650                         /* SCTP Socket API Extension
6651                          * 5.3.4 SCTP Send Information Structure (SCTP_SNDINFO)
6652                          *
6653                          * This cmsghdr structure specifies SCTP options for
6654                          * sendmsg(). This structure and SCTP_RCVINFO replaces
6655                          * SCTP_SNDRCV which has been deprecated.
6656                          *
6657                          * cmsg_level    cmsg_type      cmsg_data[]
6658                          * ------------  ------------   ---------------------
6659                          * IPPROTO_SCTP  SCTP_SNDINFO    struct sctp_sndinfo
6660                          */
6661                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_sndinfo)))
6662                                 return -EINVAL;
6663 
6664                         cmsgs->sinfo = CMSG_DATA(cmsg);
6665 
6666                         if (cmsgs->sinfo->snd_flags &
6667                             ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
6668                               SCTP_ABORT | SCTP_EOF))
6669                                 return -EINVAL;
6670                         break;
6671                 default:
6672                         return -EINVAL;
6673                 }
6674         }
6675 
6676         return 0;
6677 }
6678 
6679 /*
6680  * Wait for a packet..
6681  * Note: This function is the same function as in core/datagram.c
6682  * with a few modifications to make lksctp work.
6683  */
6684 static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p)
6685 {
6686         int error;
6687         DEFINE_WAIT(wait);
6688 
6689         prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
6690 
6691         /* Socket errors? */
6692         error = sock_error(sk);
6693         if (error)
6694                 goto out;
6695 
6696         if (!skb_queue_empty(&sk->sk_receive_queue))
6697                 goto ready;
6698 
6699         /* Socket shut down?  */
6700         if (sk->sk_shutdown & RCV_SHUTDOWN)
6701                 goto out;
6702 
6703         /* Sequenced packets can come disconnected.  If so we report the
6704          * problem.
6705          */
6706         error = -ENOTCONN;
6707 
6708         /* Is there a good reason to think that we may receive some data?  */
6709         if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
6710                 goto out;
6711 
6712         /* Handle signals.  */
6713         if (signal_pending(current))
6714                 goto interrupted;
6715 
6716         /* Let another process have a go.  Since we are going to sleep
6717          * anyway.  Note: This may cause odd behaviors if the message
6718          * does not fit in the user's buffer, but this seems to be the
6719          * only way to honor MSG_DONTWAIT realistically.
6720          */
6721         release_sock(sk);
6722         *timeo_p = schedule_timeout(*timeo_p);
6723         lock_sock(sk);
6724 
6725 ready:
6726         finish_wait(sk_sleep(sk), &wait);
6727         return 0;
6728 
6729 interrupted:
6730         error = sock_intr_errno(*timeo_p);
6731 
6732 out:
6733         finish_wait(sk_sleep(sk), &wait);
6734         *err = error;
6735         return error;
6736 }
6737 
6738 /* Receive a datagram.
6739  * Note: This is pretty much the same routine as in core/datagram.c
6740  * with a few changes to make lksctp work.
6741  */
6742 struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
6743                                        int noblock, int *err)
6744 {
6745         int error;
6746         struct sk_buff *skb;
6747         long timeo;
6748 
6749         timeo = sock_rcvtimeo(sk, noblock);
6750 
6751         pr_debug("%s: timeo:%ld, max:%ld\n", __func__, timeo,
6752                  MAX_SCHEDULE_TIMEOUT);
6753 
6754         do {
6755                 /* Again only user level code calls this function,
6756                  * so nothing interrupt level
6757                  * will suddenly eat the receive_queue.
6758                  *
6759                  *  Look at current nfs client by the way...
6760                  *  However, this function was correct in any case. 8)
6761                  */
6762                 if (flags & MSG_PEEK) {
6763                         spin_lock_bh(&sk->sk_receive_queue.lock);
6764                         skb = skb_peek(&sk->sk_receive_queue);
6765                         if (skb)
6766                                 atomic_inc(&skb->users);
6767                         spin_unlock_bh(&sk->sk_receive_queue.lock);
6768                 } else {
6769                         skb = skb_dequeue(&sk->sk_receive_queue);
6770                 }
6771 
6772                 if (skb)
6773                         return skb;
6774 
6775                 /* Caller is allowed not to check sk->sk_err before calling. */
6776                 error = sock_error(sk);
6777                 if (error)
6778                         goto no_packet;
6779 
6780                 if (sk->sk_shutdown & RCV_SHUTDOWN)
6781                         break;
6782 
6783                 if (sk_can_busy_loop(sk) &&
6784                     sk_busy_loop(sk, noblock))
6785                         continue;
6786 
6787                 /* User doesn't want to wait.  */
6788                 error = -EAGAIN;
6789                 if (!timeo)
6790                         goto no_packet;
6791         } while (sctp_wait_for_packet(sk, err, &timeo) == 0);
6792 
6793         return NULL;
6794 
6795 no_packet:
6796         *err = error;
6797         return NULL;
6798 }
6799 
6800 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
6801 static void __sctp_write_space(struct sctp_association *asoc)
6802 {
6803         struct sock *sk = asoc->base.sk;
6804         struct socket *sock = sk->sk_socket;
6805 
6806         if ((sctp_wspace(asoc) > 0) && sock) {
6807                 if (waitqueue_active(&asoc->wait))
6808                         wake_up_interruptible(&asoc->wait);
6809 
6810                 if (sctp_writeable(sk)) {
6811                         wait_queue_head_t *wq = sk_sleep(sk);
6812 
6813                         if (wq && waitqueue_active(wq))
6814                                 wake_up_interruptible(wq);
6815 
6816                         /* Note that we try to include the Async I/O support
6817                          * here by modeling from the current TCP/UDP code.
6818                          * We have not tested with it yet.
6819                          */
6820                         if (!(sk->sk_shutdown & SEND_SHUTDOWN))
6821                                 sock_wake_async(sock,
6822                                                 SOCK_WAKE_SPACE, POLL_OUT);
6823                 }
6824         }
6825 }
6826 
6827 static void sctp_wake_up_waiters(struct sock *sk,
6828                                  struct sctp_association *asoc)
6829 {
6830         struct sctp_association *tmp = asoc;
6831 
6832         /* We do accounting for the sndbuf space per association,
6833          * so we only need to wake our own association.
6834          */
6835         if (asoc->ep->sndbuf_policy)
6836                 return __sctp_write_space(asoc);
6837 
6838         /* If association goes down and is just flushing its
6839          * outq, then just normally notify others.
6840          */
6841         if (asoc->base.dead)
6842                 return sctp_write_space(sk);
6843 
6844         /* Accounting for the sndbuf space is per socket, so we
6845          * need to wake up others, try to be fair and in case of
6846          * other associations, let them have a go first instead
6847          * of just doing a sctp_write_space() call.
6848          *
6849          * Note that we reach sctp_wake_up_waiters() only when
6850          * associations free up queued chunks, thus we are under
6851          * lock and the list of associations on a socket is
6852          * guaranteed not to change.
6853          */
6854         for (tmp = list_next_entry(tmp, asocs); 1;
6855              tmp = list_next_entry(tmp, asocs)) {
6856                 /* Manually skip the head element. */
6857                 if (&tmp->asocs == &((sctp_sk(sk))->ep->asocs))
6858                         continue;
6859                 /* Wake up association. */
6860                 __sctp_write_space(tmp);
6861                 /* We've reached the end. */
6862                 if (tmp == asoc)
6863                         break;
6864         }
6865 }
6866 
6867 /* Do accounting for the sndbuf space.
6868  * Decrement the used sndbuf space of the corresponding association by the
6869  * data size which was just transmitted(freed).
6870  */
6871 static void sctp_wfree(struct sk_buff *skb)
6872 {
6873         struct sctp_chunk *chunk = skb_shinfo(skb)->destructor_arg;
6874         struct sctp_association *asoc = chunk->asoc;
6875         struct sock *sk = asoc->base.sk;
6876 
6877         asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
6878                                 sizeof(struct sk_buff) +
6879                                 sizeof(struct sctp_chunk);
6880 
6881         atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
6882 
6883         /*
6884          * This undoes what is done via sctp_set_owner_w and sk_mem_charge
6885          */
6886         sk->sk_wmem_queued   -= skb->truesize;
6887         sk_mem_uncharge(sk, skb->truesize);
6888 
6889         sock_wfree(skb);
6890         sctp_wake_up_waiters(sk, asoc);
6891 
6892         sctp_association_put(asoc);
6893 }
6894 
6895 /* Do accounting for the receive space on the socket.
6896  * Accounting for the association is done in ulpevent.c
6897  * We set this as a destructor for the cloned data skbs so that
6898  * accounting is done at the correct time.
6899  */
6900 void sctp_sock_rfree(struct sk_buff *skb)
6901 {
6902         struct sock *sk = skb->sk;
6903         struct sctp_ulpevent *event = sctp_skb2event(skb);
6904 
6905         atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
6906 
6907         /*
6908          * Mimic the behavior of sock_rfree
6909          */
6910         sk_mem_uncharge(sk, event->rmem_len);
6911 }
6912 
6913 
6914 /* Helper function to wait for space in the sndbuf.  */
6915 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
6916                                 size_t msg_len)
6917 {
6918         struct sock *sk = asoc->base.sk;
6919         int err = 0;
6920         long current_timeo = *timeo_p;
6921         DEFINE_WAIT(wait);
6922 
6923         pr_debug("%s: asoc:%p, timeo:%ld, msg_len:%zu\n", __func__, asoc,
6924                  *timeo_p, msg_len);
6925 
6926         /* Increment the association's refcnt.  */
6927         sctp_association_hold(asoc);
6928 
6929         /* Wait on the association specific sndbuf space. */
6930         for (;;) {
6931                 prepare_to_wait_exclusive(&asoc->wait, &wait,
6932                                           TASK_INTERRUPTIBLE);
6933                 if (!*timeo_p)
6934                         goto do_nonblock;
6935                 if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6936                     asoc->base.dead)
6937                         goto do_error;
6938                 if (signal_pending(current))
6939                         goto do_interrupted;
6940                 if (msg_len <= sctp_wspace(asoc))
6941                         break;
6942 
6943                 /* Let another process have a go.  Since we are going
6944                  * to sleep anyway.
6945                  */
6946                 release_sock(sk);
6947                 current_timeo = schedule_timeout(current_timeo);
6948                 BUG_ON(sk != asoc->base.sk);
6949                 lock_sock(sk);
6950 
6951                 *timeo_p = current_timeo;
6952         }
6953 
6954 out:
6955         finish_wait(&asoc->wait, &wait);
6956 
6957         /* Release the association's refcnt.  */
6958         sctp_association_put(asoc);
6959 
6960         return err;
6961 
6962 do_error:
6963         err = -EPIPE;
6964         goto out;
6965 
6966 do_interrupted:
6967         err = sock_intr_errno(*timeo_p);
6968         goto out;
6969 
6970 do_nonblock:
6971         err = -EAGAIN;
6972         goto out;
6973 }
6974 
6975 void sctp_data_ready(struct sock *sk)
6976 {
6977         struct socket_wq *wq;
6978 
6979         rcu_read_lock();
6980         wq = rcu_dereference(sk->sk_wq);
6981         if (wq_has_sleeper(wq))
6982                 wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
6983                                                 POLLRDNORM | POLLRDBAND);
6984         sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
6985         rcu_read_unlock();
6986 }
6987 
6988 /* If socket sndbuf has changed, wake up all per association waiters.  */
6989 void sctp_write_space(struct sock *sk)
6990 {
6991         struct sctp_association *asoc;
6992 
6993         /* Wake up the tasks in each wait queue.  */
6994         list_for_each_entry(asoc, &((sctp_sk(sk))->ep->asocs), asocs) {
6995                 __sctp_write_space(asoc);
6996         }
6997 }
6998 
6999 /* Is there any sndbuf space available on the socket?
7000  *
7001  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
7002  * associations on the same socket.  For a UDP-style socket with
7003  * multiple associations, it is possible for it to be "unwriteable"
7004  * prematurely.  I assume that this is acceptable because
7005  * a premature "unwriteable" is better than an accidental "writeable" which
7006  * would cause an unwanted block under certain circumstances.  For the 1-1
7007  * UDP-style sockets or TCP-style sockets, this code should work.
7008  *  - Daisy
7009  */
7010 static int sctp_writeable(struct sock *sk)
7011 {
7012         int amt = 0;
7013 
7014         amt = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
7015         if (amt < 0)
7016                 amt = 0;
7017         return amt;
7018 }
7019 
7020 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
7021  * returns immediately with EINPROGRESS.
7022  */
7023 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
7024 {
7025         struct sock *sk = asoc->base.sk;
7026         int err = 0;
7027         long current_timeo = *timeo_p;
7028         DEFINE_WAIT(wait);
7029 
7030         pr_debug("%s: asoc:%p, timeo:%ld\n", __func__, asoc, *timeo_p);
7031 
7032         /* Increment the association's refcnt.  */
7033         sctp_association_hold(asoc);
7034 
7035         for (;;) {
7036                 prepare_to_wait_exclusive(&asoc->wait, &wait,
7037                                           TASK_INTERRUPTIBLE);
7038                 if (!*timeo_p)
7039                         goto do_nonblock;
7040                 if (sk->sk_shutdown & RCV_SHUTDOWN)
7041                         break;
7042                 if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
7043                     asoc->base.dead)
7044                         goto do_error;
7045                 if (signal_pending(current))
7046                         goto do_interrupted;
7047 
7048                 if (sctp_state(asoc, ESTABLISHED))
7049                         break;
7050 
7051                 /* Let another process have a go.  Since we are going
7052                  * to sleep anyway.
7053                  */
7054                 release_sock(sk);
7055                 current_timeo = schedule_timeout(current_timeo);
7056                 lock_sock(sk);
7057 
7058                 *timeo_p = current_timeo;
7059         }
7060 
7061 out:
7062         finish_wait(&asoc->wait, &wait);