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TOMOYO Linux Cross Reference
Linux/net/phonet/pep.c

Version: ~ [ linux-5.6-rc1 ] ~ [ linux-5.5.2 ] ~ [ linux-5.4.17 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.102 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.170 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.213 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.213 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.81 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * File: pep.c
  3  *
  4  * Phonet pipe protocol end point socket
  5  *
  6  * Copyright (C) 2008 Nokia Corporation.
  7  *
  8  * Author: RĂ©mi Denis-Courmont
  9  *
 10  * This program is free software; you can redistribute it and/or
 11  * modify it under the terms of the GNU General Public License
 12  * version 2 as published by the Free Software Foundation.
 13  *
 14  * This program is distributed in the hope that it will be useful, but
 15  * WITHOUT ANY WARRANTY; without even the implied warranty of
 16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 17  * General Public License for more details.
 18  *
 19  * You should have received a copy of the GNU General Public License
 20  * along with this program; if not, write to the Free Software
 21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 22  * 02110-1301 USA
 23  */
 24 
 25 #include <linux/kernel.h>
 26 #include <linux/slab.h>
 27 #include <linux/socket.h>
 28 #include <net/sock.h>
 29 #include <net/tcp_states.h>
 30 #include <asm/ioctls.h>
 31 
 32 #include <linux/phonet.h>
 33 #include <linux/module.h>
 34 #include <net/phonet/phonet.h>
 35 #include <net/phonet/pep.h>
 36 #include <net/phonet/gprs.h>
 37 
 38 /* sk_state values:
 39  * TCP_CLOSE            sock not in use yet
 40  * TCP_CLOSE_WAIT       disconnected pipe
 41  * TCP_LISTEN           listening pipe endpoint
 42  * TCP_SYN_RECV         connected pipe in disabled state
 43  * TCP_ESTABLISHED      connected pipe in enabled state
 44  *
 45  * pep_sock locking:
 46  *  - sk_state, hlist: sock lock needed
 47  *  - listener: read only
 48  *  - pipe_handle: read only
 49  */
 50 
 51 #define CREDITS_MAX     10
 52 #define CREDITS_THR     7
 53 
 54 #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */
 55 
 56 /* Get the next TLV sub-block. */
 57 static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen,
 58                                         void *buf)
 59 {
 60         void *data = NULL;
 61         struct {
 62                 u8 sb_type;
 63                 u8 sb_len;
 64         } *ph, h;
 65         int buflen = *plen;
 66 
 67         ph = skb_header_pointer(skb, 0, 2, &h);
 68         if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len))
 69                 return NULL;
 70         ph->sb_len -= 2;
 71         *ptype = ph->sb_type;
 72         *plen = ph->sb_len;
 73 
 74         if (buflen > ph->sb_len)
 75                 buflen = ph->sb_len;
 76         data = skb_header_pointer(skb, 2, buflen, buf);
 77         __skb_pull(skb, 2 + ph->sb_len);
 78         return data;
 79 }
 80 
 81 static struct sk_buff *pep_alloc_skb(struct sock *sk, const void *payload,
 82                                         int len, gfp_t priority)
 83 {
 84         struct sk_buff *skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority);
 85         if (!skb)
 86                 return NULL;
 87         skb_set_owner_w(skb, sk);
 88 
 89         skb_reserve(skb, MAX_PNPIPE_HEADER);
 90         __skb_put(skb, len);
 91         skb_copy_to_linear_data(skb, payload, len);
 92         __skb_push(skb, sizeof(struct pnpipehdr));
 93         skb_reset_transport_header(skb);
 94         return skb;
 95 }
 96 
 97 static int pep_reply(struct sock *sk, struct sk_buff *oskb, u8 code,
 98                         const void *data, int len, gfp_t priority)
 99 {
100         const struct pnpipehdr *oph = pnp_hdr(oskb);
101         struct pnpipehdr *ph;
102         struct sk_buff *skb;
103         struct sockaddr_pn peer;
104 
105         skb = pep_alloc_skb(sk, data, len, priority);
106         if (!skb)
107                 return -ENOMEM;
108 
109         ph = pnp_hdr(skb);
110         ph->utid = oph->utid;
111         ph->message_id = oph->message_id + 1; /* REQ -> RESP */
112         ph->pipe_handle = oph->pipe_handle;
113         ph->error_code = code;
114 
115         pn_skb_get_src_sockaddr(oskb, &peer);
116         return pn_skb_send(sk, skb, &peer);
117 }
118 
119 static int pep_indicate(struct sock *sk, u8 id, u8 code,
120                         const void *data, int len, gfp_t priority)
121 {
122         struct pep_sock *pn = pep_sk(sk);
123         struct pnpipehdr *ph;
124         struct sk_buff *skb;
125 
126         skb = pep_alloc_skb(sk, data, len, priority);
127         if (!skb)
128                 return -ENOMEM;
129 
130         ph = pnp_hdr(skb);
131         ph->utid = 0;
132         ph->message_id = id;
133         ph->pipe_handle = pn->pipe_handle;
134         ph->data[0] = code;
135         return pn_skb_send(sk, skb, NULL);
136 }
137 
138 #define PAD 0x00
139 
140 static int pipe_handler_request(struct sock *sk, u8 id, u8 code,
141                                 const void *data, int len)
142 {
143         struct pep_sock *pn = pep_sk(sk);
144         struct pnpipehdr *ph;
145         struct sk_buff *skb;
146 
147         skb = pep_alloc_skb(sk, data, len, GFP_KERNEL);
148         if (!skb)
149                 return -ENOMEM;
150 
151         ph = pnp_hdr(skb);
152         ph->utid = id; /* whatever */
153         ph->message_id = id;
154         ph->pipe_handle = pn->pipe_handle;
155         ph->data[0] = code;
156         return pn_skb_send(sk, skb, NULL);
157 }
158 
159 static int pipe_handler_send_created_ind(struct sock *sk)
160 {
161         struct pep_sock *pn = pep_sk(sk);
162         u8 data[4] = {
163                 PN_PIPE_SB_NEGOTIATED_FC, pep_sb_size(2),
164                 pn->tx_fc, pn->rx_fc,
165         };
166 
167         return pep_indicate(sk, PNS_PIPE_CREATED_IND, 1 /* sub-blocks */,
168                                 data, 4, GFP_ATOMIC);
169 }
170 
171 static int pep_accept_conn(struct sock *sk, struct sk_buff *skb)
172 {
173         static const u8 data[20] = {
174                 PAD, PAD, PAD, 2 /* sub-blocks */,
175                 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD,
176                         PN_MULTI_CREDIT_FLOW_CONTROL,
177                         PN_ONE_CREDIT_FLOW_CONTROL,
178                         PN_LEGACY_FLOW_CONTROL,
179                         PAD,
180                 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD,
181                         PN_MULTI_CREDIT_FLOW_CONTROL,
182                         PN_ONE_CREDIT_FLOW_CONTROL,
183                         PN_LEGACY_FLOW_CONTROL,
184                         PAD,
185         };
186 
187         might_sleep();
188         return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data),
189                                 GFP_KERNEL);
190 }
191 
192 static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code,
193                                 gfp_t priority)
194 {
195         static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ };
196         WARN_ON(code == PN_PIPE_NO_ERROR);
197         return pep_reply(sk, skb, code, data, sizeof(data), priority);
198 }
199 
200 /* Control requests are not sent by the pipe service and have a specific
201  * message format. */
202 static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
203                                 gfp_t priority)
204 {
205         const struct pnpipehdr *oph = pnp_hdr(oskb);
206         struct sk_buff *skb;
207         struct pnpipehdr *ph;
208         struct sockaddr_pn dst;
209         u8 data[4] = {
210                 oph->data[0], /* PEP type */
211                 code, /* error code, at an unusual offset */
212                 PAD, PAD,
213         };
214 
215         skb = pep_alloc_skb(sk, data, 4, priority);
216         if (!skb)
217                 return -ENOMEM;
218 
219         ph = pnp_hdr(skb);
220         ph->utid = oph->utid;
221         ph->message_id = PNS_PEP_CTRL_RESP;
222         ph->pipe_handle = oph->pipe_handle;
223         ph->data[0] = oph->data[1]; /* CTRL id */
224 
225         pn_skb_get_src_sockaddr(oskb, &dst);
226         return pn_skb_send(sk, skb, &dst);
227 }
228 
229 static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority)
230 {
231         u8 data[4] = { type, PAD, PAD, status };
232 
233         return pep_indicate(sk, PNS_PEP_STATUS_IND, PN_PEP_TYPE_COMMON,
234                                 data, 4, priority);
235 }
236 
237 /* Send our RX flow control information to the sender.
238  * Socket must be locked. */
239 static void pipe_grant_credits(struct sock *sk, gfp_t priority)
240 {
241         struct pep_sock *pn = pep_sk(sk);
242 
243         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
244 
245         switch (pn->rx_fc) {
246         case PN_LEGACY_FLOW_CONTROL: /* TODO */
247                 break;
248         case PN_ONE_CREDIT_FLOW_CONTROL:
249                 if (pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL,
250                                         PEP_IND_READY, priority) == 0)
251                         pn->rx_credits = 1;
252                 break;
253         case PN_MULTI_CREDIT_FLOW_CONTROL:
254                 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX)
255                         break;
256                 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
257                                         CREDITS_MAX - pn->rx_credits,
258                                         priority) == 0)
259                         pn->rx_credits = CREDITS_MAX;
260                 break;
261         }
262 }
263 
264 static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
265 {
266         struct pep_sock *pn = pep_sk(sk);
267         struct pnpipehdr *hdr;
268         int wake = 0;
269 
270         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
271                 return -EINVAL;
272 
273         hdr = pnp_hdr(skb);
274         if (hdr->data[0] != PN_PEP_TYPE_COMMON) {
275                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n",
276                                 (unsigned int)hdr->data[0]);
277                 return -EOPNOTSUPP;
278         }
279 
280         switch (hdr->data[1]) {
281         case PN_PEP_IND_FLOW_CONTROL:
282                 switch (pn->tx_fc) {
283                 case PN_LEGACY_FLOW_CONTROL:
284                         switch (hdr->data[4]) {
285                         case PEP_IND_BUSY:
286                                 atomic_set(&pn->tx_credits, 0);
287                                 break;
288                         case PEP_IND_READY:
289                                 atomic_set(&pn->tx_credits, wake = 1);
290                                 break;
291                         }
292                         break;
293                 case PN_ONE_CREDIT_FLOW_CONTROL:
294                         if (hdr->data[4] == PEP_IND_READY)
295                                 atomic_set(&pn->tx_credits, wake = 1);
296                         break;
297                 }
298                 break;
299 
300         case PN_PEP_IND_ID_MCFC_GRANT_CREDITS:
301                 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL)
302                         break;
303                 atomic_add(wake = hdr->data[4], &pn->tx_credits);
304                 break;
305 
306         default:
307                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n",
308                                 (unsigned int)hdr->data[1]);
309                 return -EOPNOTSUPP;
310         }
311         if (wake)
312                 sk->sk_write_space(sk);
313         return 0;
314 }
315 
316 static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb)
317 {
318         struct pep_sock *pn = pep_sk(sk);
319         struct pnpipehdr *hdr = pnp_hdr(skb);
320         u8 n_sb = hdr->data[0];
321 
322         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
323         __skb_pull(skb, sizeof(*hdr));
324         while (n_sb > 0) {
325                 u8 type, buf[2], len = sizeof(buf);
326                 u8 *data = pep_get_sb(skb, &type, &len, buf);
327 
328                 if (data == NULL)
329                         return -EINVAL;
330                 switch (type) {
331                 case PN_PIPE_SB_NEGOTIATED_FC:
332                         if (len < 2 || (data[0] | data[1]) > 3)
333                                 break;
334                         pn->tx_fc = data[0] & 3;
335                         pn->rx_fc = data[1] & 3;
336                         break;
337                 }
338                 n_sb--;
339         }
340         return 0;
341 }
342 
343 /* Queue an skb to a connected sock.
344  * Socket lock must be held. */
345 static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
346 {
347         struct pep_sock *pn = pep_sk(sk);
348         struct pnpipehdr *hdr = pnp_hdr(skb);
349         struct sk_buff_head *queue;
350         int err = 0;
351 
352         BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
353 
354         switch (hdr->message_id) {
355         case PNS_PEP_CONNECT_REQ:
356                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_ATOMIC);
357                 break;
358 
359         case PNS_PEP_DISCONNECT_REQ:
360                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
361                 sk->sk_state = TCP_CLOSE_WAIT;
362                 if (!sock_flag(sk, SOCK_DEAD))
363                         sk->sk_state_change(sk);
364                 break;
365 
366         case PNS_PEP_ENABLE_REQ:
367                 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */
368                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
369                 break;
370 
371         case PNS_PEP_RESET_REQ:
372                 switch (hdr->state_after_reset) {
373                 case PN_PIPE_DISABLE:
374                         pn->init_enable = 0;
375                         break;
376                 case PN_PIPE_ENABLE:
377                         pn->init_enable = 1;
378                         break;
379                 default: /* not allowed to send an error here!? */
380                         err = -EINVAL;
381                         goto out;
382                 }
383                 /* fall through */
384         case PNS_PEP_DISABLE_REQ:
385                 atomic_set(&pn->tx_credits, 0);
386                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
387                 break;
388 
389         case PNS_PEP_CTRL_REQ:
390                 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) {
391                         atomic_inc(&sk->sk_drops);
392                         break;
393                 }
394                 __skb_pull(skb, 4);
395                 queue = &pn->ctrlreq_queue;
396                 goto queue;
397 
398         case PNS_PIPE_ALIGNED_DATA:
399                 __skb_pull(skb, 1);
400                 /* fall through */
401         case PNS_PIPE_DATA:
402                 __skb_pull(skb, 3); /* Pipe data header */
403                 if (!pn_flow_safe(pn->rx_fc)) {
404                         err = sock_queue_rcv_skb(sk, skb);
405                         if (!err)
406                                 return NET_RX_SUCCESS;
407                         err = -ENOBUFS;
408                         break;
409                 }
410 
411                 if (pn->rx_credits == 0) {
412                         atomic_inc(&sk->sk_drops);
413                         err = -ENOBUFS;
414                         break;
415                 }
416                 pn->rx_credits--;
417                 queue = &sk->sk_receive_queue;
418                 goto queue;
419 
420         case PNS_PEP_STATUS_IND:
421                 pipe_rcv_status(sk, skb);
422                 break;
423 
424         case PNS_PIPE_REDIRECTED_IND:
425                 err = pipe_rcv_created(sk, skb);
426                 break;
427 
428         case PNS_PIPE_CREATED_IND:
429                 err = pipe_rcv_created(sk, skb);
430                 if (err)
431                         break;
432                 /* fall through */
433         case PNS_PIPE_RESET_IND:
434                 if (!pn->init_enable)
435                         break;
436                 /* fall through */
437         case PNS_PIPE_ENABLED_IND:
438                 if (!pn_flow_safe(pn->tx_fc)) {
439                         atomic_set(&pn->tx_credits, 1);
440                         sk->sk_write_space(sk);
441                 }
442                 if (sk->sk_state == TCP_ESTABLISHED)
443                         break; /* Nothing to do */
444                 sk->sk_state = TCP_ESTABLISHED;
445                 pipe_grant_credits(sk, GFP_ATOMIC);
446                 break;
447 
448         case PNS_PIPE_DISABLED_IND:
449                 sk->sk_state = TCP_SYN_RECV;
450                 pn->rx_credits = 0;
451                 break;
452 
453         default:
454                 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n",
455                                 hdr->message_id);
456                 err = -EINVAL;
457         }
458 out:
459         kfree_skb(skb);
460         return (err == -ENOBUFS) ? NET_RX_DROP : NET_RX_SUCCESS;
461 
462 queue:
463         skb->dev = NULL;
464         skb_set_owner_r(skb, sk);
465         err = skb->len;
466         skb_queue_tail(queue, skb);
467         if (!sock_flag(sk, SOCK_DEAD))
468                 sk->sk_data_ready(sk, err);
469         return NET_RX_SUCCESS;
470 }
471 
472 /* Destroy connected sock. */
473 static void pipe_destruct(struct sock *sk)
474 {
475         struct pep_sock *pn = pep_sk(sk);
476 
477         skb_queue_purge(&sk->sk_receive_queue);
478         skb_queue_purge(&pn->ctrlreq_queue);
479 }
480 
481 static u8 pipe_negotiate_fc(const u8 *fcs, unsigned int n)
482 {
483         unsigned int i;
484         u8 final_fc = PN_NO_FLOW_CONTROL;
485 
486         for (i = 0; i < n; i++) {
487                 u8 fc = fcs[i];
488 
489                 if (fc > final_fc && fc < PN_MAX_FLOW_CONTROL)
490                         final_fc = fc;
491         }
492         return final_fc;
493 }
494 
495 static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb)
496 {
497         struct pep_sock *pn = pep_sk(sk);
498         struct pnpipehdr *hdr;
499         u8 n_sb;
500 
501         if (!pskb_pull(skb, sizeof(*hdr) + 4))
502                 return -EINVAL;
503 
504         hdr = pnp_hdr(skb);
505         if (hdr->error_code != PN_PIPE_NO_ERROR)
506                 return -ECONNREFUSED;
507 
508         /* Parse sub-blocks */
509         n_sb = hdr->data[4];
510         while (n_sb > 0) {
511                 u8 type, buf[6], len = sizeof(buf);
512                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
513 
514                 if (data == NULL)
515                         return -EINVAL;
516 
517                 switch (type) {
518                 case PN_PIPE_SB_REQUIRED_FC_TX:
519                         if (len < 2 || len < data[0])
520                                 break;
521                         pn->tx_fc = pipe_negotiate_fc(data + 2, len - 2);
522                         break;
523 
524                 case PN_PIPE_SB_PREFERRED_FC_RX:
525                         if (len < 2 || len < data[0])
526                                 break;
527                         pn->rx_fc = pipe_negotiate_fc(data + 2, len - 2);
528                         break;
529 
530                 }
531                 n_sb--;
532         }
533 
534         return pipe_handler_send_created_ind(sk);
535 }
536 
537 static int pep_enableresp_rcv(struct sock *sk, struct sk_buff *skb)
538 {
539         struct pnpipehdr *hdr = pnp_hdr(skb);
540 
541         if (hdr->error_code != PN_PIPE_NO_ERROR)
542                 return -ECONNREFUSED;
543 
544         return pep_indicate(sk, PNS_PIPE_ENABLED_IND, 0 /* sub-blocks */,
545                 NULL, 0, GFP_ATOMIC);
546 
547 }
548 
549 static void pipe_start_flow_control(struct sock *sk)
550 {
551         struct pep_sock *pn = pep_sk(sk);
552 
553         if (!pn_flow_safe(pn->tx_fc)) {
554                 atomic_set(&pn->tx_credits, 1);
555                 sk->sk_write_space(sk);
556         }
557         pipe_grant_credits(sk, GFP_ATOMIC);
558 }
559 
560 /* Queue an skb to an actively connected sock.
561  * Socket lock must be held. */
562 static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb)
563 {
564         struct pep_sock *pn = pep_sk(sk);
565         struct pnpipehdr *hdr = pnp_hdr(skb);
566         int err = NET_RX_SUCCESS;
567 
568         switch (hdr->message_id) {
569         case PNS_PIPE_ALIGNED_DATA:
570                 __skb_pull(skb, 1);
571                 /* fall through */
572         case PNS_PIPE_DATA:
573                 __skb_pull(skb, 3); /* Pipe data header */
574                 if (!pn_flow_safe(pn->rx_fc)) {
575                         err = sock_queue_rcv_skb(sk, skb);
576                         if (!err)
577                                 return NET_RX_SUCCESS;
578                         err = NET_RX_DROP;
579                         break;
580                 }
581 
582                 if (pn->rx_credits == 0) {
583                         atomic_inc(&sk->sk_drops);
584                         err = NET_RX_DROP;
585                         break;
586                 }
587                 pn->rx_credits--;
588                 skb->dev = NULL;
589                 skb_set_owner_r(skb, sk);
590                 err = skb->len;
591                 skb_queue_tail(&sk->sk_receive_queue, skb);
592                 if (!sock_flag(sk, SOCK_DEAD))
593                         sk->sk_data_ready(sk, err);
594                 return NET_RX_SUCCESS;
595 
596         case PNS_PEP_CONNECT_RESP:
597                 if (sk->sk_state != TCP_SYN_SENT)
598                         break;
599                 if (!sock_flag(sk, SOCK_DEAD))
600                         sk->sk_state_change(sk);
601                 if (pep_connresp_rcv(sk, skb)) {
602                         sk->sk_state = TCP_CLOSE_WAIT;
603                         break;
604                 }
605                 if (pn->init_enable == PN_PIPE_DISABLE)
606                         sk->sk_state = TCP_SYN_RECV;
607                 else {
608                         sk->sk_state = TCP_ESTABLISHED;
609                         pipe_start_flow_control(sk);
610                 }
611                 break;
612 
613         case PNS_PEP_ENABLE_RESP:
614                 if (sk->sk_state != TCP_SYN_SENT)
615                         break;
616 
617                 if (pep_enableresp_rcv(sk, skb)) {
618                         sk->sk_state = TCP_CLOSE_WAIT;
619                         break;
620                 }
621 
622                 sk->sk_state = TCP_ESTABLISHED;
623                 pipe_start_flow_control(sk);
624                 break;
625 
626         case PNS_PEP_DISCONNECT_RESP:
627                 /* sock should already be dead, nothing to do */
628                 break;
629 
630         case PNS_PEP_STATUS_IND:
631                 pipe_rcv_status(sk, skb);
632                 break;
633         }
634         kfree_skb(skb);
635         return err;
636 }
637 
638 /* Listening sock must be locked */
639 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
640                                         const struct sockaddr_pn *dst,
641                                         u8 pipe_handle)
642 {
643         struct sock *sknode;
644         u16 dobj = pn_sockaddr_get_object(dst);
645 
646         sk_for_each(sknode, hlist) {
647                 struct pep_sock *pnnode = pep_sk(sknode);
648 
649                 /* Ports match, but addresses might not: */
650                 if (pnnode->pn_sk.sobject != dobj)
651                         continue;
652                 if (pnnode->pipe_handle != pipe_handle)
653                         continue;
654                 if (sknode->sk_state == TCP_CLOSE_WAIT)
655                         continue;
656 
657                 sock_hold(sknode);
658                 return sknode;
659         }
660         return NULL;
661 }
662 
663 /*
664  * Deliver an skb to a listening sock.
665  * Socket lock must be held.
666  * We then queue the skb to the right connected sock (if any).
667  */
668 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
669 {
670         struct pep_sock *pn = pep_sk(sk);
671         struct sock *sknode;
672         struct pnpipehdr *hdr;
673         struct sockaddr_pn dst;
674         u8 pipe_handle;
675 
676         if (!pskb_may_pull(skb, sizeof(*hdr)))
677                 goto drop;
678 
679         hdr = pnp_hdr(skb);
680         pipe_handle = hdr->pipe_handle;
681         if (pipe_handle == PN_PIPE_INVALID_HANDLE)
682                 goto drop;
683 
684         pn_skb_get_dst_sockaddr(skb, &dst);
685 
686         /* Look for an existing pipe handle */
687         sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
688         if (sknode)
689                 return sk_receive_skb(sknode, skb, 1);
690 
691         switch (hdr->message_id) {
692         case PNS_PEP_CONNECT_REQ:
693                 if (sk->sk_state != TCP_LISTEN || sk_acceptq_is_full(sk)) {
694                         pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE,
695                                         GFP_ATOMIC);
696                         break;
697                 }
698                 skb_queue_head(&sk->sk_receive_queue, skb);
699                 sk_acceptq_added(sk);
700                 if (!sock_flag(sk, SOCK_DEAD))
701                         sk->sk_data_ready(sk, 0);
702                 return NET_RX_SUCCESS;
703 
704         case PNS_PEP_DISCONNECT_REQ:
705                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
706                 break;
707 
708         case PNS_PEP_CTRL_REQ:
709                 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
710                 break;
711 
712         case PNS_PEP_RESET_REQ:
713         case PNS_PEP_ENABLE_REQ:
714         case PNS_PEP_DISABLE_REQ:
715                 /* invalid handle is not even allowed here! */
716                 break;
717 
718         default:
719                 if ((1 << sk->sk_state)
720                                 & ~(TCPF_CLOSE|TCPF_LISTEN|TCPF_CLOSE_WAIT))
721                         /* actively connected socket */
722                         return pipe_handler_do_rcv(sk, skb);
723         }
724 drop:
725         kfree_skb(skb);
726         return NET_RX_SUCCESS;
727 }
728 
729 static int pipe_do_remove(struct sock *sk)
730 {
731         struct pep_sock *pn = pep_sk(sk);
732         struct pnpipehdr *ph;
733         struct sk_buff *skb;
734 
735         skb = pep_alloc_skb(sk, NULL, 0, GFP_KERNEL);
736         if (!skb)
737                 return -ENOMEM;
738 
739         ph = pnp_hdr(skb);
740         ph->utid = 0;
741         ph->message_id = PNS_PIPE_REMOVE_REQ;
742         ph->pipe_handle = pn->pipe_handle;
743         ph->data[0] = PAD;
744         return pn_skb_send(sk, skb, NULL);
745 }
746 
747 /* associated socket ceases to exist */
748 static void pep_sock_close(struct sock *sk, long timeout)
749 {
750         struct pep_sock *pn = pep_sk(sk);
751         int ifindex = 0;
752 
753         sock_hold(sk); /* keep a reference after sk_common_release() */
754         sk_common_release(sk);
755 
756         lock_sock(sk);
757         if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) {
758                 if (sk->sk_backlog_rcv == pipe_do_rcv)
759                         /* Forcefully remove dangling Phonet pipe */
760                         pipe_do_remove(sk);
761                 else
762                         pipe_handler_request(sk, PNS_PEP_DISCONNECT_REQ, PAD,
763                                                 NULL, 0);
764         }
765         sk->sk_state = TCP_CLOSE;
766 
767         ifindex = pn->ifindex;
768         pn->ifindex = 0;
769         release_sock(sk);
770 
771         if (ifindex)
772                 gprs_detach(sk);
773         sock_put(sk);
774 }
775 
776 static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp)
777 {
778         struct pep_sock *pn = pep_sk(sk), *newpn;
779         struct sock *newsk = NULL;
780         struct sk_buff *skb;
781         struct pnpipehdr *hdr;
782         struct sockaddr_pn dst, src;
783         int err;
784         u16 peer_type;
785         u8 pipe_handle, enabled, n_sb;
786         u8 aligned = 0;
787 
788         skb = skb_recv_datagram(sk, 0, flags & O_NONBLOCK, errp);
789         if (!skb)
790                 return NULL;
791 
792         lock_sock(sk);
793         if (sk->sk_state != TCP_LISTEN) {
794                 err = -EINVAL;
795                 goto drop;
796         }
797         sk_acceptq_removed(sk);
798 
799         err = -EPROTO;
800         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
801                 goto drop;
802 
803         hdr = pnp_hdr(skb);
804         pipe_handle = hdr->pipe_handle;
805         switch (hdr->state_after_connect) {
806         case PN_PIPE_DISABLE:
807                 enabled = 0;
808                 break;
809         case PN_PIPE_ENABLE:
810                 enabled = 1;
811                 break;
812         default:
813                 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM,
814                                 GFP_KERNEL);
815                 goto drop;
816         }
817         peer_type = hdr->other_pep_type << 8;
818 
819         /* Parse sub-blocks (options) */
820         n_sb = hdr->data[4];
821         while (n_sb > 0) {
822                 u8 type, buf[1], len = sizeof(buf);
823                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
824 
825                 if (data == NULL)
826                         goto drop;
827                 switch (type) {
828                 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
829                         if (len < 1)
830                                 goto drop;
831                         peer_type = (peer_type & 0xff00) | data[0];
832                         break;
833                 case PN_PIPE_SB_ALIGNED_DATA:
834                         aligned = data[0] != 0;
835                         break;
836                 }
837                 n_sb--;
838         }
839 
840         /* Check for duplicate pipe handle */
841         newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
842         if (unlikely(newsk)) {
843                 __sock_put(newsk);
844                 newsk = NULL;
845                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_KERNEL);
846                 goto drop;
847         }
848 
849         /* Create a new to-be-accepted sock */
850         newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_KERNEL, sk->sk_prot);
851         if (!newsk) {
852                 pep_reject_conn(sk, skb, PN_PIPE_ERR_OVERLOAD, GFP_KERNEL);
853                 err = -ENOBUFS;
854                 goto drop;
855         }
856 
857         sock_init_data(NULL, newsk);
858         newsk->sk_state = TCP_SYN_RECV;
859         newsk->sk_backlog_rcv = pipe_do_rcv;
860         newsk->sk_protocol = sk->sk_protocol;
861         newsk->sk_destruct = pipe_destruct;
862 
863         newpn = pep_sk(newsk);
864         pn_skb_get_dst_sockaddr(skb, &dst);
865         pn_skb_get_src_sockaddr(skb, &src);
866         newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
867         newpn->pn_sk.dobject = pn_sockaddr_get_object(&src);
868         newpn->pn_sk.resource = pn_sockaddr_get_resource(&dst);
869         sock_hold(sk);
870         newpn->listener = sk;
871         skb_queue_head_init(&newpn->ctrlreq_queue);
872         newpn->pipe_handle = pipe_handle;
873         atomic_set(&newpn->tx_credits, 0);
874         newpn->ifindex = 0;
875         newpn->peer_type = peer_type;
876         newpn->rx_credits = 0;
877         newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
878         newpn->init_enable = enabled;
879         newpn->aligned = aligned;
880 
881         err = pep_accept_conn(newsk, skb);
882         if (err) {
883                 sock_put(newsk);
884                 newsk = NULL;
885                 goto drop;
886         }
887         sk_add_node(newsk, &pn->hlist);
888 drop:
889         release_sock(sk);
890         kfree_skb(skb);
891         *errp = err;
892         return newsk;
893 }
894 
895 static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len)
896 {
897         struct pep_sock *pn = pep_sk(sk);
898         int err;
899         u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD };
900 
901         if (pn->pipe_handle == PN_PIPE_INVALID_HANDLE)
902                 pn->pipe_handle = 1; /* anything but INVALID_HANDLE */
903 
904         err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ,
905                                 pn->init_enable, data, 4);
906         if (err) {
907                 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
908                 return err;
909         }
910 
911         sk->sk_state = TCP_SYN_SENT;
912 
913         return 0;
914 }
915 
916 static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len)
917 {
918         int err;
919 
920         err = pipe_handler_request(sk, PNS_PEP_ENABLE_REQ, PAD,
921                                 NULL, 0);
922         if (err)
923                 return err;
924 
925         sk->sk_state = TCP_SYN_SENT;
926 
927         return 0;
928 }
929 
930 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
931 {
932         struct pep_sock *pn = pep_sk(sk);
933         int answ;
934         int ret = -ENOIOCTLCMD;
935 
936         switch (cmd) {
937         case SIOCINQ:
938                 if (sk->sk_state == TCP_LISTEN) {
939                         ret = -EINVAL;
940                         break;
941                 }
942 
943                 lock_sock(sk);
944                 if (sock_flag(sk, SOCK_URGINLINE) &&
945                     !skb_queue_empty(&pn->ctrlreq_queue))
946                         answ = skb_peek(&pn->ctrlreq_queue)->len;
947                 else if (!skb_queue_empty(&sk->sk_receive_queue))
948                         answ = skb_peek(&sk->sk_receive_queue)->len;
949                 else
950                         answ = 0;
951                 release_sock(sk);
952                 ret = put_user(answ, (int __user *)arg);
953                 break;
954 
955         case SIOCPNENABLEPIPE:
956                 lock_sock(sk);
957                 if (sk->sk_state == TCP_SYN_SENT)
958                         ret =  -EBUSY;
959                 else if (sk->sk_state == TCP_ESTABLISHED)
960                         ret = -EISCONN;
961                 else
962                         ret = pep_sock_enable(sk, NULL, 0);
963                 release_sock(sk);
964                 break;
965         }
966 
967         return ret;
968 }
969 
970 static int pep_init(struct sock *sk)
971 {
972         struct pep_sock *pn = pep_sk(sk);
973 
974         sk->sk_destruct = pipe_destruct;
975         INIT_HLIST_HEAD(&pn->hlist);
976         pn->listener = NULL;
977         skb_queue_head_init(&pn->ctrlreq_queue);
978         atomic_set(&pn->tx_credits, 0);
979         pn->ifindex = 0;
980         pn->peer_type = 0;
981         pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
982         pn->rx_credits = 0;
983         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
984         pn->init_enable = 1;
985         pn->aligned = 0;
986         return 0;
987 }
988 
989 static int pep_setsockopt(struct sock *sk, int level, int optname,
990                                 char __user *optval, unsigned int optlen)
991 {
992         struct pep_sock *pn = pep_sk(sk);
993         int val = 0, err = 0;
994 
995         if (level != SOL_PNPIPE)
996                 return -ENOPROTOOPT;
997         if (optlen >= sizeof(int)) {
998                 if (get_user(val, (int __user *) optval))
999                         return -EFAULT;
1000         }
1001 
1002         lock_sock(sk);
1003         switch (optname) {
1004         case PNPIPE_ENCAP:
1005                 if (val && val != PNPIPE_ENCAP_IP) {
1006                         err = -EINVAL;
1007                         break;
1008                 }
1009                 if (!pn->ifindex == !val)
1010                         break; /* Nothing to do! */
1011                 if (!capable(CAP_NET_ADMIN)) {
1012                         err = -EPERM;
1013                         break;
1014                 }
1015                 if (val) {
1016                         release_sock(sk);
1017                         err = gprs_attach(sk);
1018                         if (err > 0) {
1019                                 pn->ifindex = err;
1020                                 err = 0;
1021                         }
1022                 } else {
1023                         pn->ifindex = 0;
1024                         release_sock(sk);
1025                         gprs_detach(sk);
1026                         err = 0;
1027                 }
1028                 goto out_norel;
1029 
1030         case PNPIPE_HANDLE:
1031                 if ((sk->sk_state == TCP_CLOSE) &&
1032                         (val >= 0) && (val < PN_PIPE_INVALID_HANDLE))
1033                         pn->pipe_handle = val;
1034                 else
1035                         err = -EINVAL;
1036                 break;
1037 
1038         case PNPIPE_INITSTATE:
1039                 pn->init_enable = !!val;
1040                 break;
1041 
1042         default:
1043                 err = -ENOPROTOOPT;
1044         }
1045         release_sock(sk);
1046 
1047 out_norel:
1048         return err;
1049 }
1050 
1051 static int pep_getsockopt(struct sock *sk, int level, int optname,
1052                                 char __user *optval, int __user *optlen)
1053 {
1054         struct pep_sock *pn = pep_sk(sk);
1055         int len, val;
1056 
1057         if (level != SOL_PNPIPE)
1058                 return -ENOPROTOOPT;
1059         if (get_user(len, optlen))
1060                 return -EFAULT;
1061 
1062         switch (optname) {
1063         case PNPIPE_ENCAP:
1064                 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
1065                 break;
1066 
1067         case PNPIPE_IFINDEX:
1068                 val = pn->ifindex;
1069                 break;
1070 
1071         case PNPIPE_HANDLE:
1072                 val = pn->pipe_handle;
1073                 if (val == PN_PIPE_INVALID_HANDLE)
1074                         return -EINVAL;
1075                 break;
1076 
1077         case PNPIPE_INITSTATE:
1078                 val = pn->init_enable;
1079                 break;
1080 
1081         default:
1082                 return -ENOPROTOOPT;
1083         }
1084 
1085         len = min_t(unsigned int, sizeof(int), len);
1086         if (put_user(len, optlen))
1087                 return -EFAULT;
1088         if (put_user(val, (int __user *) optval))
1089                 return -EFAULT;
1090         return 0;
1091 }
1092 
1093 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
1094 {
1095         struct pep_sock *pn = pep_sk(sk);
1096         struct pnpipehdr *ph;
1097         int err;
1098 
1099         if (pn_flow_safe(pn->tx_fc) &&
1100             !atomic_add_unless(&pn->tx_credits, -1, 0)) {
1101                 kfree_skb(skb);
1102                 return -ENOBUFS;
1103         }
1104 
1105         skb_push(skb, 3 + pn->aligned);
1106         skb_reset_transport_header(skb);
1107         ph = pnp_hdr(skb);
1108         ph->utid = 0;
1109         if (pn->aligned) {
1110                 ph->message_id = PNS_PIPE_ALIGNED_DATA;
1111                 ph->data[0] = 0; /* padding */
1112         } else
1113                 ph->message_id = PNS_PIPE_DATA;
1114         ph->pipe_handle = pn->pipe_handle;
1115         err = pn_skb_send(sk, skb, NULL);
1116 
1117         if (err && pn_flow_safe(pn->tx_fc))
1118                 atomic_inc(&pn->tx_credits);
1119         return err;
1120 
1121 }
1122 
1123 static int pep_sendmsg(struct kiocb *iocb, struct sock *sk,
1124                         struct msghdr *msg, size_t len)
1125 {
1126         struct pep_sock *pn = pep_sk(sk);
1127         struct sk_buff *skb;
1128         long timeo;
1129         int flags = msg->msg_flags;
1130         int err, done;
1131 
1132         if (len > USHRT_MAX)
1133                 return -EMSGSIZE;
1134 
1135         if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
1136                                 MSG_CMSG_COMPAT)) ||
1137                         !(msg->msg_flags & MSG_EOR))
1138                 return -EOPNOTSUPP;
1139 
1140         skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
1141                                         flags & MSG_DONTWAIT, &err);
1142         if (!skb)
1143                 return err;
1144 
1145         skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned);
1146         err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1147         if (err < 0)
1148                 goto outfree;
1149 
1150         lock_sock(sk);
1151         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1152         if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
1153                 err = -ENOTCONN;
1154                 goto out;
1155         }
1156         if (sk->sk_state != TCP_ESTABLISHED) {
1157                 /* Wait until the pipe gets to enabled state */
1158 disabled:
1159                 err = sk_stream_wait_connect(sk, &timeo);
1160                 if (err)
1161                         goto out;
1162 
1163                 if (sk->sk_state == TCP_CLOSE_WAIT) {
1164                         err = -ECONNRESET;
1165                         goto out;
1166                 }
1167         }
1168         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
1169 
1170         /* Wait until flow control allows TX */
1171         done = atomic_read(&pn->tx_credits);
1172         while (!done) {
1173                 DEFINE_WAIT(wait);
1174 
1175                 if (!timeo) {
1176                         err = -EAGAIN;
1177                         goto out;
1178                 }
1179                 if (signal_pending(current)) {
1180                         err = sock_intr_errno(timeo);
1181                         goto out;
1182                 }
1183 
1184                 prepare_to_wait(sk_sleep(sk), &wait,
1185                                 TASK_INTERRUPTIBLE);
1186                 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits));
1187                 finish_wait(sk_sleep(sk), &wait);
1188 
1189                 if (sk->sk_state != TCP_ESTABLISHED)
1190                         goto disabled;
1191         }
1192 
1193         err = pipe_skb_send(sk, skb);
1194         if (err >= 0)
1195                 err = len; /* success! */
1196         skb = NULL;
1197 out:
1198         release_sock(sk);
1199 outfree:
1200         kfree_skb(skb);
1201         return err;
1202 }
1203 
1204 int pep_writeable(struct sock *sk)
1205 {
1206         struct pep_sock *pn = pep_sk(sk);
1207 
1208         return atomic_read(&pn->tx_credits);
1209 }
1210 
1211 int pep_write(struct sock *sk, struct sk_buff *skb)
1212 {
1213         struct sk_buff *rskb, *fs;
1214         int flen = 0;
1215 
1216         if (pep_sk(sk)->aligned)
1217                 return pipe_skb_send(sk, skb);
1218 
1219         rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
1220         if (!rskb) {
1221                 kfree_skb(skb);
1222                 return -ENOMEM;
1223         }
1224         skb_shinfo(rskb)->frag_list = skb;
1225         rskb->len += skb->len;
1226         rskb->data_len += rskb->len;
1227         rskb->truesize += rskb->len;
1228 
1229         /* Avoid nested fragments */
1230         skb_walk_frags(skb, fs)
1231                 flen += fs->len;
1232         skb->next = skb_shinfo(skb)->frag_list;
1233         skb_frag_list_init(skb);
1234         skb->len -= flen;
1235         skb->data_len -= flen;
1236         skb->truesize -= flen;
1237 
1238         skb_reserve(rskb, MAX_PHONET_HEADER + 3);
1239         return pipe_skb_send(sk, rskb);
1240 }
1241 
1242 struct sk_buff *pep_read(struct sock *sk)
1243 {
1244         struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
1245 
1246         if (sk->sk_state == TCP_ESTABLISHED)
1247                 pipe_grant_credits(sk, GFP_ATOMIC);
1248         return skb;
1249 }
1250 
1251 static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
1252                         struct msghdr *msg, size_t len, int noblock,
1253                         int flags, int *addr_len)
1254 {
1255         struct sk_buff *skb;
1256         int err;
1257 
1258         if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
1259                         MSG_NOSIGNAL|MSG_CMSG_COMPAT))
1260                 return -EOPNOTSUPP;
1261 
1262         if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
1263                 return -ENOTCONN;
1264 
1265         if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
1266                 /* Dequeue and acknowledge control request */
1267                 struct pep_sock *pn = pep_sk(sk);
1268 
1269                 if (flags & MSG_PEEK)
1270                         return -EOPNOTSUPP;
1271                 skb = skb_dequeue(&pn->ctrlreq_queue);
1272                 if (skb) {
1273                         pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1274                                                 GFP_KERNEL);
1275                         msg->msg_flags |= MSG_OOB;
1276                         goto copy;
1277                 }
1278                 if (flags & MSG_OOB)
1279                         return -EINVAL;
1280         }
1281 
1282         skb = skb_recv_datagram(sk, flags, noblock, &err);
1283         lock_sock(sk);
1284         if (skb == NULL) {
1285                 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1286                         err = -ECONNRESET;
1287                 release_sock(sk);
1288                 return err;
1289         }
1290 
1291         if (sk->sk_state == TCP_ESTABLISHED)
1292                 pipe_grant_credits(sk, GFP_KERNEL);
1293         release_sock(sk);
1294 copy:
1295         msg->msg_flags |= MSG_EOR;
1296         if (skb->len > len)
1297                 msg->msg_flags |= MSG_TRUNC;
1298         else
1299                 len = skb->len;
1300 
1301         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
1302         if (!err)
1303                 err = (flags & MSG_TRUNC) ? skb->len : len;
1304 
1305         skb_free_datagram(sk, skb);
1306         return err;
1307 }
1308 
1309 static void pep_sock_unhash(struct sock *sk)
1310 {
1311         struct pep_sock *pn = pep_sk(sk);
1312         struct sock *skparent = NULL;
1313 
1314         lock_sock(sk);
1315 
1316         if (pn->listener != NULL) {
1317                 skparent = pn->listener;
1318                 pn->listener = NULL;
1319                 release_sock(sk);
1320 
1321                 pn = pep_sk(skparent);
1322                 lock_sock(skparent);
1323                 sk_del_node_init(sk);
1324                 sk = skparent;
1325         }
1326 
1327         /* Unhash a listening sock only when it is closed
1328          * and all of its active connected pipes are closed. */
1329         if (hlist_empty(&pn->hlist))
1330                 pn_sock_unhash(&pn->pn_sk.sk);
1331         release_sock(sk);
1332 
1333         if (skparent)
1334                 sock_put(skparent);
1335 }
1336 
1337 static struct proto pep_proto = {
1338         .close          = pep_sock_close,
1339         .accept         = pep_sock_accept,
1340         .connect        = pep_sock_connect,
1341         .ioctl          = pep_ioctl,
1342         .init           = pep_init,
1343         .setsockopt     = pep_setsockopt,
1344         .getsockopt     = pep_getsockopt,
1345         .sendmsg        = pep_sendmsg,
1346         .recvmsg        = pep_recvmsg,
1347         .backlog_rcv    = pep_do_rcv,
1348         .hash           = pn_sock_hash,
1349         .unhash         = pep_sock_unhash,
1350         .get_port       = pn_sock_get_port,
1351         .obj_size       = sizeof(struct pep_sock),
1352         .owner          = THIS_MODULE,
1353         .name           = "PNPIPE",
1354 };
1355 
1356 static struct phonet_protocol pep_pn_proto = {
1357         .ops            = &phonet_stream_ops,
1358         .prot           = &pep_proto,
1359         .sock_type      = SOCK_SEQPACKET,
1360 };
1361 
1362 static int __init pep_register(void)
1363 {
1364         return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1365 }
1366 
1367 static void __exit pep_unregister(void)
1368 {
1369         phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1370 }
1371 
1372 module_init(pep_register);
1373 module_exit(pep_unregister);
1374 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1375 MODULE_DESCRIPTION("Phonet pipe protocol");
1376 MODULE_LICENSE("GPL");
1377 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);
1378 

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