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

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  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                 net_dbg_ratelimited("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                 net_dbg_ratelimited("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                 net_dbg_ratelimited("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         skb_queue_tail(queue, skb);
466         if (!sock_flag(sk, SOCK_DEAD))
467                 sk->sk_data_ready(sk);
468         return NET_RX_SUCCESS;
469 }
470 
471 /* Destroy connected sock. */
472 static void pipe_destruct(struct sock *sk)
473 {
474         struct pep_sock *pn = pep_sk(sk);
475 
476         skb_queue_purge(&sk->sk_receive_queue);
477         skb_queue_purge(&pn->ctrlreq_queue);
478 }
479 
480 static u8 pipe_negotiate_fc(const u8 *fcs, unsigned int n)
481 {
482         unsigned int i;
483         u8 final_fc = PN_NO_FLOW_CONTROL;
484 
485         for (i = 0; i < n; i++) {
486                 u8 fc = fcs[i];
487 
488                 if (fc > final_fc && fc < PN_MAX_FLOW_CONTROL)
489                         final_fc = fc;
490         }
491         return final_fc;
492 }
493 
494 static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb)
495 {
496         struct pep_sock *pn = pep_sk(sk);
497         struct pnpipehdr *hdr;
498         u8 n_sb;
499 
500         if (!pskb_pull(skb, sizeof(*hdr) + 4))
501                 return -EINVAL;
502 
503         hdr = pnp_hdr(skb);
504         if (hdr->error_code != PN_PIPE_NO_ERROR)
505                 return -ECONNREFUSED;
506 
507         /* Parse sub-blocks */
508         n_sb = hdr->data[4];
509         while (n_sb > 0) {
510                 u8 type, buf[6], len = sizeof(buf);
511                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
512 
513                 if (data == NULL)
514                         return -EINVAL;
515 
516                 switch (type) {
517                 case PN_PIPE_SB_REQUIRED_FC_TX:
518                         if (len < 2 || len < data[0])
519                                 break;
520                         pn->tx_fc = pipe_negotiate_fc(data + 2, len - 2);
521                         break;
522 
523                 case PN_PIPE_SB_PREFERRED_FC_RX:
524                         if (len < 2 || len < data[0])
525                                 break;
526                         pn->rx_fc = pipe_negotiate_fc(data + 2, len - 2);
527                         break;
528 
529                 }
530                 n_sb--;
531         }
532 
533         return pipe_handler_send_created_ind(sk);
534 }
535 
536 static int pep_enableresp_rcv(struct sock *sk, struct sk_buff *skb)
537 {
538         struct pnpipehdr *hdr = pnp_hdr(skb);
539 
540         if (hdr->error_code != PN_PIPE_NO_ERROR)
541                 return -ECONNREFUSED;
542 
543         return pep_indicate(sk, PNS_PIPE_ENABLED_IND, 0 /* sub-blocks */,
544                 NULL, 0, GFP_ATOMIC);
545 
546 }
547 
548 static void pipe_start_flow_control(struct sock *sk)
549 {
550         struct pep_sock *pn = pep_sk(sk);
551 
552         if (!pn_flow_safe(pn->tx_fc)) {
553                 atomic_set(&pn->tx_credits, 1);
554                 sk->sk_write_space(sk);
555         }
556         pipe_grant_credits(sk, GFP_ATOMIC);
557 }
558 
559 /* Queue an skb to an actively connected sock.
560  * Socket lock must be held. */
561 static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb)
562 {
563         struct pep_sock *pn = pep_sk(sk);
564         struct pnpipehdr *hdr = pnp_hdr(skb);
565         int err = NET_RX_SUCCESS;
566 
567         switch (hdr->message_id) {
568         case PNS_PIPE_ALIGNED_DATA:
569                 __skb_pull(skb, 1);
570                 /* fall through */
571         case PNS_PIPE_DATA:
572                 __skb_pull(skb, 3); /* Pipe data header */
573                 if (!pn_flow_safe(pn->rx_fc)) {
574                         err = sock_queue_rcv_skb(sk, skb);
575                         if (!err)
576                                 return NET_RX_SUCCESS;
577                         err = NET_RX_DROP;
578                         break;
579                 }
580 
581                 if (pn->rx_credits == 0) {
582                         atomic_inc(&sk->sk_drops);
583                         err = NET_RX_DROP;
584                         break;
585                 }
586                 pn->rx_credits--;
587                 skb->dev = NULL;
588                 skb_set_owner_r(skb, sk);
589                 skb_queue_tail(&sk->sk_receive_queue, skb);
590                 if (!sock_flag(sk, SOCK_DEAD))
591                         sk->sk_data_ready(sk);
592                 return NET_RX_SUCCESS;
593 
594         case PNS_PEP_CONNECT_RESP:
595                 if (sk->sk_state != TCP_SYN_SENT)
596                         break;
597                 if (!sock_flag(sk, SOCK_DEAD))
598                         sk->sk_state_change(sk);
599                 if (pep_connresp_rcv(sk, skb)) {
600                         sk->sk_state = TCP_CLOSE_WAIT;
601                         break;
602                 }
603                 if (pn->init_enable == PN_PIPE_DISABLE)
604                         sk->sk_state = TCP_SYN_RECV;
605                 else {
606                         sk->sk_state = TCP_ESTABLISHED;
607                         pipe_start_flow_control(sk);
608                 }
609                 break;
610 
611         case PNS_PEP_ENABLE_RESP:
612                 if (sk->sk_state != TCP_SYN_SENT)
613                         break;
614 
615                 if (pep_enableresp_rcv(sk, skb)) {
616                         sk->sk_state = TCP_CLOSE_WAIT;
617                         break;
618                 }
619 
620                 sk->sk_state = TCP_ESTABLISHED;
621                 pipe_start_flow_control(sk);
622                 break;
623 
624         case PNS_PEP_DISCONNECT_RESP:
625                 /* sock should already be dead, nothing to do */
626                 break;
627 
628         case PNS_PEP_STATUS_IND:
629                 pipe_rcv_status(sk, skb);
630                 break;
631         }
632         kfree_skb(skb);
633         return err;
634 }
635 
636 /* Listening sock must be locked */
637 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
638                                         const struct sockaddr_pn *dst,
639                                         u8 pipe_handle)
640 {
641         struct sock *sknode;
642         u16 dobj = pn_sockaddr_get_object(dst);
643 
644         sk_for_each(sknode, hlist) {
645                 struct pep_sock *pnnode = pep_sk(sknode);
646 
647                 /* Ports match, but addresses might not: */
648                 if (pnnode->pn_sk.sobject != dobj)
649                         continue;
650                 if (pnnode->pipe_handle != pipe_handle)
651                         continue;
652                 if (sknode->sk_state == TCP_CLOSE_WAIT)
653                         continue;
654 
655                 sock_hold(sknode);
656                 return sknode;
657         }
658         return NULL;
659 }
660 
661 /*
662  * Deliver an skb to a listening sock.
663  * Socket lock must be held.
664  * We then queue the skb to the right connected sock (if any).
665  */
666 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
667 {
668         struct pep_sock *pn = pep_sk(sk);
669         struct sock *sknode;
670         struct pnpipehdr *hdr;
671         struct sockaddr_pn dst;
672         u8 pipe_handle;
673 
674         if (!pskb_may_pull(skb, sizeof(*hdr)))
675                 goto drop;
676 
677         hdr = pnp_hdr(skb);
678         pipe_handle = hdr->pipe_handle;
679         if (pipe_handle == PN_PIPE_INVALID_HANDLE)
680                 goto drop;
681 
682         pn_skb_get_dst_sockaddr(skb, &dst);
683 
684         /* Look for an existing pipe handle */
685         sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
686         if (sknode)
687                 return sk_receive_skb(sknode, skb, 1);
688 
689         switch (hdr->message_id) {
690         case PNS_PEP_CONNECT_REQ:
691                 if (sk->sk_state != TCP_LISTEN || sk_acceptq_is_full(sk)) {
692                         pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE,
693                                         GFP_ATOMIC);
694                         break;
695                 }
696                 skb_queue_head(&sk->sk_receive_queue, skb);
697                 sk_acceptq_added(sk);
698                 if (!sock_flag(sk, SOCK_DEAD))
699                         sk->sk_data_ready(sk);
700                 return NET_RX_SUCCESS;
701 
702         case PNS_PEP_DISCONNECT_REQ:
703                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
704                 break;
705 
706         case PNS_PEP_CTRL_REQ:
707                 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
708                 break;
709 
710         case PNS_PEP_RESET_REQ:
711         case PNS_PEP_ENABLE_REQ:
712         case PNS_PEP_DISABLE_REQ:
713                 /* invalid handle is not even allowed here! */
714                 break;
715 
716         default:
717                 if ((1 << sk->sk_state)
718                                 & ~(TCPF_CLOSE|TCPF_LISTEN|TCPF_CLOSE_WAIT))
719                         /* actively connected socket */
720                         return pipe_handler_do_rcv(sk, skb);
721         }
722 drop:
723         kfree_skb(skb);
724         return NET_RX_SUCCESS;
725 }
726 
727 static int pipe_do_remove(struct sock *sk)
728 {
729         struct pep_sock *pn = pep_sk(sk);
730         struct pnpipehdr *ph;
731         struct sk_buff *skb;
732 
733         skb = pep_alloc_skb(sk, NULL, 0, GFP_KERNEL);
734         if (!skb)
735                 return -ENOMEM;
736 
737         ph = pnp_hdr(skb);
738         ph->utid = 0;
739         ph->message_id = PNS_PIPE_REMOVE_REQ;
740         ph->pipe_handle = pn->pipe_handle;
741         ph->data[0] = PAD;
742         return pn_skb_send(sk, skb, NULL);
743 }
744 
745 /* associated socket ceases to exist */
746 static void pep_sock_close(struct sock *sk, long timeout)
747 {
748         struct pep_sock *pn = pep_sk(sk);
749         int ifindex = 0;
750 
751         sock_hold(sk); /* keep a reference after sk_common_release() */
752         sk_common_release(sk);
753 
754         lock_sock(sk);
755         if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) {
756                 if (sk->sk_backlog_rcv == pipe_do_rcv)
757                         /* Forcefully remove dangling Phonet pipe */
758                         pipe_do_remove(sk);
759                 else
760                         pipe_handler_request(sk, PNS_PEP_DISCONNECT_REQ, PAD,
761                                                 NULL, 0);
762         }
763         sk->sk_state = TCP_CLOSE;
764 
765         ifindex = pn->ifindex;
766         pn->ifindex = 0;
767         release_sock(sk);
768 
769         if (ifindex)
770                 gprs_detach(sk);
771         sock_put(sk);
772 }
773 
774 static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp)
775 {
776         struct pep_sock *pn = pep_sk(sk), *newpn;
777         struct sock *newsk = NULL;
778         struct sk_buff *skb;
779         struct pnpipehdr *hdr;
780         struct sockaddr_pn dst, src;
781         int err;
782         u16 peer_type;
783         u8 pipe_handle, enabled, n_sb;
784         u8 aligned = 0;
785 
786         skb = skb_recv_datagram(sk, 0, flags & O_NONBLOCK, errp);
787         if (!skb)
788                 return NULL;
789 
790         lock_sock(sk);
791         if (sk->sk_state != TCP_LISTEN) {
792                 err = -EINVAL;
793                 goto drop;
794         }
795         sk_acceptq_removed(sk);
796 
797         err = -EPROTO;
798         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
799                 goto drop;
800 
801         hdr = pnp_hdr(skb);
802         pipe_handle = hdr->pipe_handle;
803         switch (hdr->state_after_connect) {
804         case PN_PIPE_DISABLE:
805                 enabled = 0;
806                 break;
807         case PN_PIPE_ENABLE:
808                 enabled = 1;
809                 break;
810         default:
811                 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM,
812                                 GFP_KERNEL);
813                 goto drop;
814         }
815         peer_type = hdr->other_pep_type << 8;
816 
817         /* Parse sub-blocks (options) */
818         n_sb = hdr->data[4];
819         while (n_sb > 0) {
820                 u8 type, buf[1], len = sizeof(buf);
821                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
822 
823                 if (data == NULL)
824                         goto drop;
825                 switch (type) {
826                 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
827                         if (len < 1)
828                                 goto drop;
829                         peer_type = (peer_type & 0xff00) | data[0];
830                         break;
831                 case PN_PIPE_SB_ALIGNED_DATA:
832                         aligned = data[0] != 0;
833                         break;
834                 }
835                 n_sb--;
836         }
837 
838         /* Check for duplicate pipe handle */
839         newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
840         if (unlikely(newsk)) {
841                 __sock_put(newsk);
842                 newsk = NULL;
843                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_KERNEL);
844                 goto drop;
845         }
846 
847         /* Create a new to-be-accepted sock */
848         newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_KERNEL, sk->sk_prot, 0);
849         if (!newsk) {
850                 pep_reject_conn(sk, skb, PN_PIPE_ERR_OVERLOAD, GFP_KERNEL);
851                 err = -ENOBUFS;
852                 goto drop;
853         }
854 
855         sock_init_data(NULL, newsk);
856         newsk->sk_state = TCP_SYN_RECV;
857         newsk->sk_backlog_rcv = pipe_do_rcv;
858         newsk->sk_protocol = sk->sk_protocol;
859         newsk->sk_destruct = pipe_destruct;
860 
861         newpn = pep_sk(newsk);
862         pn_skb_get_dst_sockaddr(skb, &dst);
863         pn_skb_get_src_sockaddr(skb, &src);
864         newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
865         newpn->pn_sk.dobject = pn_sockaddr_get_object(&src);
866         newpn->pn_sk.resource = pn_sockaddr_get_resource(&dst);
867         sock_hold(sk);
868         newpn->listener = sk;
869         skb_queue_head_init(&newpn->ctrlreq_queue);
870         newpn->pipe_handle = pipe_handle;
871         atomic_set(&newpn->tx_credits, 0);
872         newpn->ifindex = 0;
873         newpn->peer_type = peer_type;
874         newpn->rx_credits = 0;
875         newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
876         newpn->init_enable = enabled;
877         newpn->aligned = aligned;
878 
879         err = pep_accept_conn(newsk, skb);
880         if (err) {
881                 sock_put(newsk);
882                 newsk = NULL;
883                 goto drop;
884         }
885         sk_add_node(newsk, &pn->hlist);
886 drop:
887         release_sock(sk);
888         kfree_skb(skb);
889         *errp = err;
890         return newsk;
891 }
892 
893 static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len)
894 {
895         struct pep_sock *pn = pep_sk(sk);
896         int err;
897         u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD };
898 
899         if (pn->pipe_handle == PN_PIPE_INVALID_HANDLE)
900                 pn->pipe_handle = 1; /* anything but INVALID_HANDLE */
901 
902         err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ,
903                                 pn->init_enable, data, 4);
904         if (err) {
905                 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
906                 return err;
907         }
908 
909         sk->sk_state = TCP_SYN_SENT;
910 
911         return 0;
912 }
913 
914 static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len)
915 {
916         int err;
917 
918         err = pipe_handler_request(sk, PNS_PEP_ENABLE_REQ, PAD,
919                                 NULL, 0);
920         if (err)
921                 return err;
922 
923         sk->sk_state = TCP_SYN_SENT;
924 
925         return 0;
926 }
927 
928 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
929 {
930         struct pep_sock *pn = pep_sk(sk);
931         int answ;
932         int ret = -ENOIOCTLCMD;
933 
934         switch (cmd) {
935         case SIOCINQ:
936                 if (sk->sk_state == TCP_LISTEN) {
937                         ret = -EINVAL;
938                         break;
939                 }
940 
941                 lock_sock(sk);
942                 if (sock_flag(sk, SOCK_URGINLINE) &&
943                     !skb_queue_empty(&pn->ctrlreq_queue))
944                         answ = skb_peek(&pn->ctrlreq_queue)->len;
945                 else if (!skb_queue_empty(&sk->sk_receive_queue))
946                         answ = skb_peek(&sk->sk_receive_queue)->len;
947                 else
948                         answ = 0;
949                 release_sock(sk);
950                 ret = put_user(answ, (int __user *)arg);
951                 break;
952 
953         case SIOCPNENABLEPIPE:
954                 lock_sock(sk);
955                 if (sk->sk_state == TCP_SYN_SENT)
956                         ret =  -EBUSY;
957                 else if (sk->sk_state == TCP_ESTABLISHED)
958                         ret = -EISCONN;
959                 else
960                         ret = pep_sock_enable(sk, NULL, 0);
961                 release_sock(sk);
962                 break;
963         }
964 
965         return ret;
966 }
967 
968 static int pep_init(struct sock *sk)
969 {
970         struct pep_sock *pn = pep_sk(sk);
971 
972         sk->sk_destruct = pipe_destruct;
973         INIT_HLIST_HEAD(&pn->hlist);
974         pn->listener = NULL;
975         skb_queue_head_init(&pn->ctrlreq_queue);
976         atomic_set(&pn->tx_credits, 0);
977         pn->ifindex = 0;
978         pn->peer_type = 0;
979         pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
980         pn->rx_credits = 0;
981         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
982         pn->init_enable = 1;
983         pn->aligned = 0;
984         return 0;
985 }
986 
987 static int pep_setsockopt(struct sock *sk, int level, int optname,
988                                 char __user *optval, unsigned int optlen)
989 {
990         struct pep_sock *pn = pep_sk(sk);
991         int val = 0, err = 0;
992 
993         if (level != SOL_PNPIPE)
994                 return -ENOPROTOOPT;
995         if (optlen >= sizeof(int)) {
996                 if (get_user(val, (int __user *) optval))
997                         return -EFAULT;
998         }
999 
1000         lock_sock(sk);
1001         switch (optname) {
1002         case PNPIPE_ENCAP:
1003                 if (val && val != PNPIPE_ENCAP_IP) {
1004                         err = -EINVAL;
1005                         break;
1006                 }
1007                 if (!pn->ifindex == !val)
1008                         break; /* Nothing to do! */
1009                 if (!capable(CAP_NET_ADMIN)) {
1010                         err = -EPERM;
1011                         break;
1012                 }
1013                 if (val) {
1014                         release_sock(sk);
1015                         err = gprs_attach(sk);
1016                         if (err > 0) {
1017                                 pn->ifindex = err;
1018                                 err = 0;
1019                         }
1020                 } else {
1021                         pn->ifindex = 0;
1022                         release_sock(sk);
1023                         gprs_detach(sk);
1024                         err = 0;
1025                 }
1026                 goto out_norel;
1027 
1028         case PNPIPE_HANDLE:
1029                 if ((sk->sk_state == TCP_CLOSE) &&
1030                         (val >= 0) && (val < PN_PIPE_INVALID_HANDLE))
1031                         pn->pipe_handle = val;
1032                 else
1033                         err = -EINVAL;
1034                 break;
1035 
1036         case PNPIPE_INITSTATE:
1037                 pn->init_enable = !!val;
1038                 break;
1039 
1040         default:
1041                 err = -ENOPROTOOPT;
1042         }
1043         release_sock(sk);
1044 
1045 out_norel:
1046         return err;
1047 }
1048 
1049 static int pep_getsockopt(struct sock *sk, int level, int optname,
1050                                 char __user *optval, int __user *optlen)
1051 {
1052         struct pep_sock *pn = pep_sk(sk);
1053         int len, val;
1054 
1055         if (level != SOL_PNPIPE)
1056                 return -ENOPROTOOPT;
1057         if (get_user(len, optlen))
1058                 return -EFAULT;
1059 
1060         switch (optname) {
1061         case PNPIPE_ENCAP:
1062                 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
1063                 break;
1064 
1065         case PNPIPE_IFINDEX:
1066                 val = pn->ifindex;
1067                 break;
1068 
1069         case PNPIPE_HANDLE:
1070                 val = pn->pipe_handle;
1071                 if (val == PN_PIPE_INVALID_HANDLE)
1072                         return -EINVAL;
1073                 break;
1074 
1075         case PNPIPE_INITSTATE:
1076                 val = pn->init_enable;
1077                 break;
1078 
1079         default:
1080                 return -ENOPROTOOPT;
1081         }
1082 
1083         len = min_t(unsigned int, sizeof(int), len);
1084         if (put_user(len, optlen))
1085                 return -EFAULT;
1086         if (put_user(val, (int __user *) optval))
1087                 return -EFAULT;
1088         return 0;
1089 }
1090 
1091 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
1092 {
1093         struct pep_sock *pn = pep_sk(sk);
1094         struct pnpipehdr *ph;
1095         int err;
1096 
1097         if (pn_flow_safe(pn->tx_fc) &&
1098             !atomic_add_unless(&pn->tx_credits, -1, 0)) {
1099                 kfree_skb(skb);
1100                 return -ENOBUFS;
1101         }
1102 
1103         skb_push(skb, 3 + pn->aligned);
1104         skb_reset_transport_header(skb);
1105         ph = pnp_hdr(skb);
1106         ph->utid = 0;
1107         if (pn->aligned) {
1108                 ph->message_id = PNS_PIPE_ALIGNED_DATA;
1109                 ph->data[0] = 0; /* padding */
1110         } else
1111                 ph->message_id = PNS_PIPE_DATA;
1112         ph->pipe_handle = pn->pipe_handle;
1113         err = pn_skb_send(sk, skb, NULL);
1114 
1115         if (err && pn_flow_safe(pn->tx_fc))
1116                 atomic_inc(&pn->tx_credits);
1117         return err;
1118 
1119 }
1120 
1121 static int pep_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1122 {
1123         struct pep_sock *pn = pep_sk(sk);
1124         struct sk_buff *skb;
1125         long timeo;
1126         int flags = msg->msg_flags;
1127         int err, done;
1128 
1129         if (len > USHRT_MAX)
1130                 return -EMSGSIZE;
1131 
1132         if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
1133                                 MSG_CMSG_COMPAT)) ||
1134                         !(msg->msg_flags & MSG_EOR))
1135                 return -EOPNOTSUPP;
1136 
1137         skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
1138                                         flags & MSG_DONTWAIT, &err);
1139         if (!skb)
1140                 return err;
1141 
1142         skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned);
1143         err = memcpy_from_msg(skb_put(skb, len), msg, len);
1144         if (err < 0)
1145                 goto outfree;
1146 
1147         lock_sock(sk);
1148         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1149         if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
1150                 err = -ENOTCONN;
1151                 goto out;
1152         }
1153         if (sk->sk_state != TCP_ESTABLISHED) {
1154                 /* Wait until the pipe gets to enabled state */
1155 disabled:
1156                 err = sk_stream_wait_connect(sk, &timeo);
1157                 if (err)
1158                         goto out;
1159 
1160                 if (sk->sk_state == TCP_CLOSE_WAIT) {
1161                         err = -ECONNRESET;
1162                         goto out;
1163                 }
1164         }
1165         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
1166 
1167         /* Wait until flow control allows TX */
1168         done = atomic_read(&pn->tx_credits);
1169         while (!done) {
1170                 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1171 
1172                 if (!timeo) {
1173                         err = -EAGAIN;
1174                         goto out;
1175                 }
1176                 if (signal_pending(current)) {
1177                         err = sock_intr_errno(timeo);
1178                         goto out;
1179                 }
1180 
1181                 add_wait_queue(sk_sleep(sk), &wait);
1182                 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits), &wait);
1183                 remove_wait_queue(sk_sleep(sk), &wait);
1184 
1185                 if (sk->sk_state != TCP_ESTABLISHED)
1186                         goto disabled;
1187         }
1188 
1189         err = pipe_skb_send(sk, skb);
1190         if (err >= 0)
1191                 err = len; /* success! */
1192         skb = NULL;
1193 out:
1194         release_sock(sk);
1195 outfree:
1196         kfree_skb(skb);
1197         return err;
1198 }
1199 
1200 int pep_writeable(struct sock *sk)
1201 {
1202         struct pep_sock *pn = pep_sk(sk);
1203 
1204         return atomic_read(&pn->tx_credits);
1205 }
1206 
1207 int pep_write(struct sock *sk, struct sk_buff *skb)
1208 {
1209         struct sk_buff *rskb, *fs;
1210         int flen = 0;
1211 
1212         if (pep_sk(sk)->aligned)
1213                 return pipe_skb_send(sk, skb);
1214 
1215         rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
1216         if (!rskb) {
1217                 kfree_skb(skb);
1218                 return -ENOMEM;
1219         }
1220         skb_shinfo(rskb)->frag_list = skb;
1221         rskb->len += skb->len;
1222         rskb->data_len += rskb->len;
1223         rskb->truesize += rskb->len;
1224 
1225         /* Avoid nested fragments */
1226         skb_walk_frags(skb, fs)
1227                 flen += fs->len;
1228         skb->next = skb_shinfo(skb)->frag_list;
1229         skb_frag_list_init(skb);
1230         skb->len -= flen;
1231         skb->data_len -= flen;
1232         skb->truesize -= flen;
1233 
1234         skb_reserve(rskb, MAX_PHONET_HEADER + 3);
1235         return pipe_skb_send(sk, rskb);
1236 }
1237 
1238 struct sk_buff *pep_read(struct sock *sk)
1239 {
1240         struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
1241 
1242         if (sk->sk_state == TCP_ESTABLISHED)
1243                 pipe_grant_credits(sk, GFP_ATOMIC);
1244         return skb;
1245 }
1246 
1247 static int pep_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
1248                        int noblock, int flags, int *addr_len)
1249 {
1250         struct sk_buff *skb;
1251         int err;
1252 
1253         if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
1254                         MSG_NOSIGNAL|MSG_CMSG_COMPAT))
1255                 return -EOPNOTSUPP;
1256 
1257         if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
1258                 return -ENOTCONN;
1259 
1260         if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
1261                 /* Dequeue and acknowledge control request */
1262                 struct pep_sock *pn = pep_sk(sk);
1263 
1264                 if (flags & MSG_PEEK)
1265                         return -EOPNOTSUPP;
1266                 skb = skb_dequeue(&pn->ctrlreq_queue);
1267                 if (skb) {
1268                         pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1269                                                 GFP_KERNEL);
1270                         msg->msg_flags |= MSG_OOB;
1271                         goto copy;
1272                 }
1273                 if (flags & MSG_OOB)
1274                         return -EINVAL;
1275         }
1276 
1277         skb = skb_recv_datagram(sk, flags, noblock, &err);
1278         lock_sock(sk);
1279         if (skb == NULL) {
1280                 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1281                         err = -ECONNRESET;
1282                 release_sock(sk);
1283                 return err;
1284         }
1285 
1286         if (sk->sk_state == TCP_ESTABLISHED)
1287                 pipe_grant_credits(sk, GFP_KERNEL);
1288         release_sock(sk);
1289 copy:
1290         msg->msg_flags |= MSG_EOR;
1291         if (skb->len > len)
1292                 msg->msg_flags |= MSG_TRUNC;
1293         else
1294                 len = skb->len;
1295 
1296         err = skb_copy_datagram_msg(skb, 0, msg, len);
1297         if (!err)
1298                 err = (flags & MSG_TRUNC) ? skb->len : len;
1299 
1300         skb_free_datagram(sk, skb);
1301         return err;
1302 }
1303 
1304 static void pep_sock_unhash(struct sock *sk)
1305 {
1306         struct pep_sock *pn = pep_sk(sk);
1307         struct sock *skparent = NULL;
1308 
1309         lock_sock(sk);
1310 
1311         if (pn->listener != NULL) {
1312                 skparent = pn->listener;
1313                 pn->listener = NULL;
1314                 release_sock(sk);
1315 
1316                 pn = pep_sk(skparent);
1317                 lock_sock(skparent);
1318                 sk_del_node_init(sk);
1319                 sk = skparent;
1320         }
1321 
1322         /* Unhash a listening sock only when it is closed
1323          * and all of its active connected pipes are closed. */
1324         if (hlist_empty(&pn->hlist))
1325                 pn_sock_unhash(&pn->pn_sk.sk);
1326         release_sock(sk);
1327 
1328         if (skparent)
1329                 sock_put(skparent);
1330 }
1331 
1332 static struct proto pep_proto = {
1333         .close          = pep_sock_close,
1334         .accept         = pep_sock_accept,
1335         .connect        = pep_sock_connect,
1336         .ioctl          = pep_ioctl,
1337         .init           = pep_init,
1338         .setsockopt     = pep_setsockopt,
1339         .getsockopt     = pep_getsockopt,
1340         .sendmsg        = pep_sendmsg,
1341         .recvmsg        = pep_recvmsg,
1342         .backlog_rcv    = pep_do_rcv,
1343         .hash           = pn_sock_hash,
1344         .unhash         = pep_sock_unhash,
1345         .get_port       = pn_sock_get_port,
1346         .obj_size       = sizeof(struct pep_sock),
1347         .owner          = THIS_MODULE,
1348         .name           = "PNPIPE",
1349 };
1350 
1351 static struct phonet_protocol pep_pn_proto = {
1352         .ops            = &phonet_stream_ops,
1353         .prot           = &pep_proto,
1354         .sock_type      = SOCK_SEQPACKET,
1355 };
1356 
1357 static int __init pep_register(void)
1358 {
1359         return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1360 }
1361 
1362 static void __exit pep_unregister(void)
1363 {
1364         phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1365 }
1366 
1367 module_init(pep_register);
1368 module_exit(pep_unregister);
1369 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1370 MODULE_DESCRIPTION("Phonet pipe protocol");
1371 MODULE_LICENSE("GPL");
1372 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);
1373 

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