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Linux/net/phonet/pep.c

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  1 // SPDX-License-Identifier: GPL-2.0-only
  2 /*
  3  * File: pep.c
  4  *
  5  * Phonet pipe protocol end point socket
  6  *
  7  * Copyright (C) 2008 Nokia Corporation.
  8  *
  9  * Author: RĂ©mi Denis-Courmont
 10  */
 11 
 12 #include <linux/kernel.h>
 13 #include <linux/sched/signal.h>
 14 #include <linux/slab.h>
 15 #include <linux/socket.h>
 16 #include <net/sock.h>
 17 #include <net/tcp_states.h>
 18 #include <asm/ioctls.h>
 19 
 20 #include <linux/phonet.h>
 21 #include <linux/module.h>
 22 #include <net/phonet/phonet.h>
 23 #include <net/phonet/pep.h>
 24 #include <net/phonet/gprs.h>
 25 
 26 /* sk_state values:
 27  * TCP_CLOSE            sock not in use yet
 28  * TCP_CLOSE_WAIT       disconnected pipe
 29  * TCP_LISTEN           listening pipe endpoint
 30  * TCP_SYN_RECV         connected pipe in disabled state
 31  * TCP_ESTABLISHED      connected pipe in enabled state
 32  *
 33  * pep_sock locking:
 34  *  - sk_state, hlist: sock lock needed
 35  *  - listener: read only
 36  *  - pipe_handle: read only
 37  */
 38 
 39 #define CREDITS_MAX     10
 40 #define CREDITS_THR     7
 41 
 42 #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */
 43 
 44 /* Get the next TLV sub-block. */
 45 static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen,
 46                                         void *buf)
 47 {
 48         void *data = NULL;
 49         struct {
 50                 u8 sb_type;
 51                 u8 sb_len;
 52         } *ph, h;
 53         int buflen = *plen;
 54 
 55         ph = skb_header_pointer(skb, 0, 2, &h);
 56         if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len))
 57                 return NULL;
 58         ph->sb_len -= 2;
 59         *ptype = ph->sb_type;
 60         *plen = ph->sb_len;
 61 
 62         if (buflen > ph->sb_len)
 63                 buflen = ph->sb_len;
 64         data = skb_header_pointer(skb, 2, buflen, buf);
 65         __skb_pull(skb, 2 + ph->sb_len);
 66         return data;
 67 }
 68 
 69 static struct sk_buff *pep_alloc_skb(struct sock *sk, const void *payload,
 70                                         int len, gfp_t priority)
 71 {
 72         struct sk_buff *skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority);
 73         if (!skb)
 74                 return NULL;
 75         skb_set_owner_w(skb, sk);
 76 
 77         skb_reserve(skb, MAX_PNPIPE_HEADER);
 78         __skb_put(skb, len);
 79         skb_copy_to_linear_data(skb, payload, len);
 80         __skb_push(skb, sizeof(struct pnpipehdr));
 81         skb_reset_transport_header(skb);
 82         return skb;
 83 }
 84 
 85 static int pep_reply(struct sock *sk, struct sk_buff *oskb, u8 code,
 86                         const void *data, int len, gfp_t priority)
 87 {
 88         const struct pnpipehdr *oph = pnp_hdr(oskb);
 89         struct pnpipehdr *ph;
 90         struct sk_buff *skb;
 91         struct sockaddr_pn peer;
 92 
 93         skb = pep_alloc_skb(sk, data, len, priority);
 94         if (!skb)
 95                 return -ENOMEM;
 96 
 97         ph = pnp_hdr(skb);
 98         ph->utid = oph->utid;
 99         ph->message_id = oph->message_id + 1; /* REQ -> RESP */
100         ph->pipe_handle = oph->pipe_handle;
101         ph->error_code = code;
102 
103         pn_skb_get_src_sockaddr(oskb, &peer);
104         return pn_skb_send(sk, skb, &peer);
105 }
106 
107 static int pep_indicate(struct sock *sk, u8 id, u8 code,
108                         const void *data, int len, gfp_t priority)
109 {
110         struct pep_sock *pn = pep_sk(sk);
111         struct pnpipehdr *ph;
112         struct sk_buff *skb;
113 
114         skb = pep_alloc_skb(sk, data, len, priority);
115         if (!skb)
116                 return -ENOMEM;
117 
118         ph = pnp_hdr(skb);
119         ph->utid = 0;
120         ph->message_id = id;
121         ph->pipe_handle = pn->pipe_handle;
122         ph->error_code = code;
123         return pn_skb_send(sk, skb, NULL);
124 }
125 
126 #define PAD 0x00
127 
128 static int pipe_handler_request(struct sock *sk, u8 id, u8 code,
129                                 const void *data, int len)
130 {
131         struct pep_sock *pn = pep_sk(sk);
132         struct pnpipehdr *ph;
133         struct sk_buff *skb;
134 
135         skb = pep_alloc_skb(sk, data, len, GFP_KERNEL);
136         if (!skb)
137                 return -ENOMEM;
138 
139         ph = pnp_hdr(skb);
140         ph->utid = id; /* whatever */
141         ph->message_id = id;
142         ph->pipe_handle = pn->pipe_handle;
143         ph->error_code = code;
144         return pn_skb_send(sk, skb, NULL);
145 }
146 
147 static int pipe_handler_send_created_ind(struct sock *sk)
148 {
149         struct pep_sock *pn = pep_sk(sk);
150         u8 data[4] = {
151                 PN_PIPE_SB_NEGOTIATED_FC, pep_sb_size(2),
152                 pn->tx_fc, pn->rx_fc,
153         };
154 
155         return pep_indicate(sk, PNS_PIPE_CREATED_IND, 1 /* sub-blocks */,
156                                 data, 4, GFP_ATOMIC);
157 }
158 
159 static int pep_accept_conn(struct sock *sk, struct sk_buff *skb)
160 {
161         static const u8 data[20] = {
162                 PAD, PAD, PAD, 2 /* sub-blocks */,
163                 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD,
164                         PN_MULTI_CREDIT_FLOW_CONTROL,
165                         PN_ONE_CREDIT_FLOW_CONTROL,
166                         PN_LEGACY_FLOW_CONTROL,
167                         PAD,
168                 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD,
169                         PN_MULTI_CREDIT_FLOW_CONTROL,
170                         PN_ONE_CREDIT_FLOW_CONTROL,
171                         PN_LEGACY_FLOW_CONTROL,
172                         PAD,
173         };
174 
175         might_sleep();
176         return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data),
177                                 GFP_KERNEL);
178 }
179 
180 static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code,
181                                 gfp_t priority)
182 {
183         static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ };
184         WARN_ON(code == PN_PIPE_NO_ERROR);
185         return pep_reply(sk, skb, code, data, sizeof(data), priority);
186 }
187 
188 /* Control requests are not sent by the pipe service and have a specific
189  * message format. */
190 static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
191                                 gfp_t priority)
192 {
193         const struct pnpipehdr *oph = pnp_hdr(oskb);
194         struct sk_buff *skb;
195         struct pnpipehdr *ph;
196         struct sockaddr_pn dst;
197         u8 data[4] = {
198                 oph->pep_type, /* PEP type */
199                 code, /* error code, at an unusual offset */
200                 PAD, PAD,
201         };
202 
203         skb = pep_alloc_skb(sk, data, 4, priority);
204         if (!skb)
205                 return -ENOMEM;
206 
207         ph = pnp_hdr(skb);
208         ph->utid = oph->utid;
209         ph->message_id = PNS_PEP_CTRL_RESP;
210         ph->pipe_handle = oph->pipe_handle;
211         ph->data0 = oph->data[0]; /* CTRL id */
212 
213         pn_skb_get_src_sockaddr(oskb, &dst);
214         return pn_skb_send(sk, skb, &dst);
215 }
216 
217 static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority)
218 {
219         u8 data[4] = { type, PAD, PAD, status };
220 
221         return pep_indicate(sk, PNS_PEP_STATUS_IND, PN_PEP_TYPE_COMMON,
222                                 data, 4, priority);
223 }
224 
225 /* Send our RX flow control information to the sender.
226  * Socket must be locked. */
227 static void pipe_grant_credits(struct sock *sk, gfp_t priority)
228 {
229         struct pep_sock *pn = pep_sk(sk);
230 
231         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
232 
233         switch (pn->rx_fc) {
234         case PN_LEGACY_FLOW_CONTROL: /* TODO */
235                 break;
236         case PN_ONE_CREDIT_FLOW_CONTROL:
237                 if (pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL,
238                                         PEP_IND_READY, priority) == 0)
239                         pn->rx_credits = 1;
240                 break;
241         case PN_MULTI_CREDIT_FLOW_CONTROL:
242                 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX)
243                         break;
244                 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
245                                         CREDITS_MAX - pn->rx_credits,
246                                         priority) == 0)
247                         pn->rx_credits = CREDITS_MAX;
248                 break;
249         }
250 }
251 
252 static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
253 {
254         struct pep_sock *pn = pep_sk(sk);
255         struct pnpipehdr *hdr;
256         int wake = 0;
257 
258         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
259                 return -EINVAL;
260 
261         hdr = pnp_hdr(skb);
262         if (hdr->pep_type != PN_PEP_TYPE_COMMON) {
263                 net_dbg_ratelimited("Phonet unknown PEP type: %u\n",
264                                     (unsigned int)hdr->pep_type);
265                 return -EOPNOTSUPP;
266         }
267 
268         switch (hdr->data[0]) {
269         case PN_PEP_IND_FLOW_CONTROL:
270                 switch (pn->tx_fc) {
271                 case PN_LEGACY_FLOW_CONTROL:
272                         switch (hdr->data[3]) {
273                         case PEP_IND_BUSY:
274                                 atomic_set(&pn->tx_credits, 0);
275                                 break;
276                         case PEP_IND_READY:
277                                 atomic_set(&pn->tx_credits, wake = 1);
278                                 break;
279                         }
280                         break;
281                 case PN_ONE_CREDIT_FLOW_CONTROL:
282                         if (hdr->data[3] == PEP_IND_READY)
283                                 atomic_set(&pn->tx_credits, wake = 1);
284                         break;
285                 }
286                 break;
287 
288         case PN_PEP_IND_ID_MCFC_GRANT_CREDITS:
289                 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL)
290                         break;
291                 atomic_add(wake = hdr->data[3], &pn->tx_credits);
292                 break;
293 
294         default:
295                 net_dbg_ratelimited("Phonet unknown PEP indication: %u\n",
296                                     (unsigned int)hdr->data[0]);
297                 return -EOPNOTSUPP;
298         }
299         if (wake)
300                 sk->sk_write_space(sk);
301         return 0;
302 }
303 
304 static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb)
305 {
306         struct pep_sock *pn = pep_sk(sk);
307         struct pnpipehdr *hdr = pnp_hdr(skb);
308         u8 n_sb = hdr->data0;
309 
310         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
311         __skb_pull(skb, sizeof(*hdr));
312         while (n_sb > 0) {
313                 u8 type, buf[2], len = sizeof(buf);
314                 u8 *data = pep_get_sb(skb, &type, &len, buf);
315 
316                 if (data == NULL)
317                         return -EINVAL;
318                 switch (type) {
319                 case PN_PIPE_SB_NEGOTIATED_FC:
320                         if (len < 2 || (data[0] | data[1]) > 3)
321                                 break;
322                         pn->tx_fc = data[0] & 3;
323                         pn->rx_fc = data[1] & 3;
324                         break;
325                 }
326                 n_sb--;
327         }
328         return 0;
329 }
330 
331 /* Queue an skb to a connected sock.
332  * Socket lock must be held. */
333 static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
334 {
335         struct pep_sock *pn = pep_sk(sk);
336         struct pnpipehdr *hdr = pnp_hdr(skb);
337         struct sk_buff_head *queue;
338         int err = 0;
339 
340         BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
341 
342         switch (hdr->message_id) {
343         case PNS_PEP_CONNECT_REQ:
344                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_ATOMIC);
345                 break;
346 
347         case PNS_PEP_DISCONNECT_REQ:
348                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
349                 sk->sk_state = TCP_CLOSE_WAIT;
350                 if (!sock_flag(sk, SOCK_DEAD))
351                         sk->sk_state_change(sk);
352                 break;
353 
354         case PNS_PEP_ENABLE_REQ:
355                 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */
356                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
357                 break;
358 
359         case PNS_PEP_RESET_REQ:
360                 switch (hdr->state_after_reset) {
361                 case PN_PIPE_DISABLE:
362                         pn->init_enable = 0;
363                         break;
364                 case PN_PIPE_ENABLE:
365                         pn->init_enable = 1;
366                         break;
367                 default: /* not allowed to send an error here!? */
368                         err = -EINVAL;
369                         goto out;
370                 }
371                 /* fall through */
372         case PNS_PEP_DISABLE_REQ:
373                 atomic_set(&pn->tx_credits, 0);
374                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
375                 break;
376 
377         case PNS_PEP_CTRL_REQ:
378                 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) {
379                         atomic_inc(&sk->sk_drops);
380                         break;
381                 }
382                 __skb_pull(skb, 4);
383                 queue = &pn->ctrlreq_queue;
384                 goto queue;
385 
386         case PNS_PIPE_ALIGNED_DATA:
387                 __skb_pull(skb, 1);
388                 /* fall through */
389         case PNS_PIPE_DATA:
390                 __skb_pull(skb, 3); /* Pipe data header */
391                 if (!pn_flow_safe(pn->rx_fc)) {
392                         err = sock_queue_rcv_skb(sk, skb);
393                         if (!err)
394                                 return NET_RX_SUCCESS;
395                         err = -ENOBUFS;
396                         break;
397                 }
398 
399                 if (pn->rx_credits == 0) {
400                         atomic_inc(&sk->sk_drops);
401                         err = -ENOBUFS;
402                         break;
403                 }
404                 pn->rx_credits--;
405                 queue = &sk->sk_receive_queue;
406                 goto queue;
407 
408         case PNS_PEP_STATUS_IND:
409                 pipe_rcv_status(sk, skb);
410                 break;
411 
412         case PNS_PIPE_REDIRECTED_IND:
413                 err = pipe_rcv_created(sk, skb);
414                 break;
415 
416         case PNS_PIPE_CREATED_IND:
417                 err = pipe_rcv_created(sk, skb);
418                 if (err)
419                         break;
420                 /* fall through */
421         case PNS_PIPE_RESET_IND:
422                 if (!pn->init_enable)
423                         break;
424                 /* fall through */
425         case PNS_PIPE_ENABLED_IND:
426                 if (!pn_flow_safe(pn->tx_fc)) {
427                         atomic_set(&pn->tx_credits, 1);
428                         sk->sk_write_space(sk);
429                 }
430                 if (sk->sk_state == TCP_ESTABLISHED)
431                         break; /* Nothing to do */
432                 sk->sk_state = TCP_ESTABLISHED;
433                 pipe_grant_credits(sk, GFP_ATOMIC);
434                 break;
435 
436         case PNS_PIPE_DISABLED_IND:
437                 sk->sk_state = TCP_SYN_RECV;
438                 pn->rx_credits = 0;
439                 break;
440 
441         default:
442                 net_dbg_ratelimited("Phonet unknown PEP message: %u\n",
443                                     hdr->message_id);
444                 err = -EINVAL;
445         }
446 out:
447         kfree_skb(skb);
448         return (err == -ENOBUFS) ? NET_RX_DROP : NET_RX_SUCCESS;
449 
450 queue:
451         skb->dev = NULL;
452         skb_set_owner_r(skb, sk);
453         skb_queue_tail(queue, skb);
454         if (!sock_flag(sk, SOCK_DEAD))
455                 sk->sk_data_ready(sk);
456         return NET_RX_SUCCESS;
457 }
458 
459 /* Destroy connected sock. */
460 static void pipe_destruct(struct sock *sk)
461 {
462         struct pep_sock *pn = pep_sk(sk);
463 
464         skb_queue_purge(&sk->sk_receive_queue);
465         skb_queue_purge(&pn->ctrlreq_queue);
466 }
467 
468 static u8 pipe_negotiate_fc(const u8 *fcs, unsigned int n)
469 {
470         unsigned int i;
471         u8 final_fc = PN_NO_FLOW_CONTROL;
472 
473         for (i = 0; i < n; i++) {
474                 u8 fc = fcs[i];
475 
476                 if (fc > final_fc && fc < PN_MAX_FLOW_CONTROL)
477                         final_fc = fc;
478         }
479         return final_fc;
480 }
481 
482 static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb)
483 {
484         struct pep_sock *pn = pep_sk(sk);
485         struct pnpipehdr *hdr;
486         u8 n_sb;
487 
488         if (!pskb_pull(skb, sizeof(*hdr) + 4))
489                 return -EINVAL;
490 
491         hdr = pnp_hdr(skb);
492         if (hdr->error_code != PN_PIPE_NO_ERROR)
493                 return -ECONNREFUSED;
494 
495         /* Parse sub-blocks */
496         n_sb = hdr->data[3];
497         while (n_sb > 0) {
498                 u8 type, buf[6], len = sizeof(buf);
499                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
500 
501                 if (data == NULL)
502                         return -EINVAL;
503 
504                 switch (type) {
505                 case PN_PIPE_SB_REQUIRED_FC_TX:
506                         if (len < 2 || len < data[0])
507                                 break;
508                         pn->tx_fc = pipe_negotiate_fc(data + 2, len - 2);
509                         break;
510 
511                 case PN_PIPE_SB_PREFERRED_FC_RX:
512                         if (len < 2 || len < data[0])
513                                 break;
514                         pn->rx_fc = pipe_negotiate_fc(data + 2, len - 2);
515                         break;
516 
517                 }
518                 n_sb--;
519         }
520 
521         return pipe_handler_send_created_ind(sk);
522 }
523 
524 static int pep_enableresp_rcv(struct sock *sk, struct sk_buff *skb)
525 {
526         struct pnpipehdr *hdr = pnp_hdr(skb);
527 
528         if (hdr->error_code != PN_PIPE_NO_ERROR)
529                 return -ECONNREFUSED;
530 
531         return pep_indicate(sk, PNS_PIPE_ENABLED_IND, 0 /* sub-blocks */,
532                 NULL, 0, GFP_ATOMIC);
533 
534 }
535 
536 static void pipe_start_flow_control(struct sock *sk)
537 {
538         struct pep_sock *pn = pep_sk(sk);
539 
540         if (!pn_flow_safe(pn->tx_fc)) {
541                 atomic_set(&pn->tx_credits, 1);
542                 sk->sk_write_space(sk);
543         }
544         pipe_grant_credits(sk, GFP_ATOMIC);
545 }
546 
547 /* Queue an skb to an actively connected sock.
548  * Socket lock must be held. */
549 static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb)
550 {
551         struct pep_sock *pn = pep_sk(sk);
552         struct pnpipehdr *hdr = pnp_hdr(skb);
553         int err = NET_RX_SUCCESS;
554 
555         switch (hdr->message_id) {
556         case PNS_PIPE_ALIGNED_DATA:
557                 __skb_pull(skb, 1);
558                 /* fall through */
559         case PNS_PIPE_DATA:
560                 __skb_pull(skb, 3); /* Pipe data header */
561                 if (!pn_flow_safe(pn->rx_fc)) {
562                         err = sock_queue_rcv_skb(sk, skb);
563                         if (!err)
564                                 return NET_RX_SUCCESS;
565                         err = NET_RX_DROP;
566                         break;
567                 }
568 
569                 if (pn->rx_credits == 0) {
570                         atomic_inc(&sk->sk_drops);
571                         err = NET_RX_DROP;
572                         break;
573                 }
574                 pn->rx_credits--;
575                 skb->dev = NULL;
576                 skb_set_owner_r(skb, sk);
577                 skb_queue_tail(&sk->sk_receive_queue, skb);
578                 if (!sock_flag(sk, SOCK_DEAD))
579                         sk->sk_data_ready(sk);
580                 return NET_RX_SUCCESS;
581 
582         case PNS_PEP_CONNECT_RESP:
583                 if (sk->sk_state != TCP_SYN_SENT)
584                         break;
585                 if (!sock_flag(sk, SOCK_DEAD))
586                         sk->sk_state_change(sk);
587                 if (pep_connresp_rcv(sk, skb)) {
588                         sk->sk_state = TCP_CLOSE_WAIT;
589                         break;
590                 }
591                 if (pn->init_enable == PN_PIPE_DISABLE)
592                         sk->sk_state = TCP_SYN_RECV;
593                 else {
594                         sk->sk_state = TCP_ESTABLISHED;
595                         pipe_start_flow_control(sk);
596                 }
597                 break;
598 
599         case PNS_PEP_ENABLE_RESP:
600                 if (sk->sk_state != TCP_SYN_SENT)
601                         break;
602 
603                 if (pep_enableresp_rcv(sk, skb)) {
604                         sk->sk_state = TCP_CLOSE_WAIT;
605                         break;
606                 }
607 
608                 sk->sk_state = TCP_ESTABLISHED;
609                 pipe_start_flow_control(sk);
610                 break;
611 
612         case PNS_PEP_DISCONNECT_RESP:
613                 /* sock should already be dead, nothing to do */
614                 break;
615 
616         case PNS_PEP_STATUS_IND:
617                 pipe_rcv_status(sk, skb);
618                 break;
619         }
620         kfree_skb(skb);
621         return err;
622 }
623 
624 /* Listening sock must be locked */
625 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
626                                         const struct sockaddr_pn *dst,
627                                         u8 pipe_handle)
628 {
629         struct sock *sknode;
630         u16 dobj = pn_sockaddr_get_object(dst);
631 
632         sk_for_each(sknode, hlist) {
633                 struct pep_sock *pnnode = pep_sk(sknode);
634 
635                 /* Ports match, but addresses might not: */
636                 if (pnnode->pn_sk.sobject != dobj)
637                         continue;
638                 if (pnnode->pipe_handle != pipe_handle)
639                         continue;
640                 if (sknode->sk_state == TCP_CLOSE_WAIT)
641                         continue;
642 
643                 sock_hold(sknode);
644                 return sknode;
645         }
646         return NULL;
647 }
648 
649 /*
650  * Deliver an skb to a listening sock.
651  * Socket lock must be held.
652  * We then queue the skb to the right connected sock (if any).
653  */
654 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
655 {
656         struct pep_sock *pn = pep_sk(sk);
657         struct sock *sknode;
658         struct pnpipehdr *hdr;
659         struct sockaddr_pn dst;
660         u8 pipe_handle;
661 
662         if (!pskb_may_pull(skb, sizeof(*hdr)))
663                 goto drop;
664 
665         hdr = pnp_hdr(skb);
666         pipe_handle = hdr->pipe_handle;
667         if (pipe_handle == PN_PIPE_INVALID_HANDLE)
668                 goto drop;
669 
670         pn_skb_get_dst_sockaddr(skb, &dst);
671 
672         /* Look for an existing pipe handle */
673         sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
674         if (sknode)
675                 return sk_receive_skb(sknode, skb, 1);
676 
677         switch (hdr->message_id) {
678         case PNS_PEP_CONNECT_REQ:
679                 if (sk->sk_state != TCP_LISTEN || sk_acceptq_is_full(sk)) {
680                         pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE,
681                                         GFP_ATOMIC);
682                         break;
683                 }
684                 skb_queue_head(&sk->sk_receive_queue, skb);
685                 sk_acceptq_added(sk);
686                 if (!sock_flag(sk, SOCK_DEAD))
687                         sk->sk_data_ready(sk);
688                 return NET_RX_SUCCESS;
689 
690         case PNS_PEP_DISCONNECT_REQ:
691                 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
692                 break;
693 
694         case PNS_PEP_CTRL_REQ:
695                 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
696                 break;
697 
698         case PNS_PEP_RESET_REQ:
699         case PNS_PEP_ENABLE_REQ:
700         case PNS_PEP_DISABLE_REQ:
701                 /* invalid handle is not even allowed here! */
702                 break;
703 
704         default:
705                 if ((1 << sk->sk_state)
706                                 & ~(TCPF_CLOSE|TCPF_LISTEN|TCPF_CLOSE_WAIT))
707                         /* actively connected socket */
708                         return pipe_handler_do_rcv(sk, skb);
709         }
710 drop:
711         kfree_skb(skb);
712         return NET_RX_SUCCESS;
713 }
714 
715 static int pipe_do_remove(struct sock *sk)
716 {
717         struct pep_sock *pn = pep_sk(sk);
718         struct pnpipehdr *ph;
719         struct sk_buff *skb;
720 
721         skb = pep_alloc_skb(sk, NULL, 0, GFP_KERNEL);
722         if (!skb)
723                 return -ENOMEM;
724 
725         ph = pnp_hdr(skb);
726         ph->utid = 0;
727         ph->message_id = PNS_PIPE_REMOVE_REQ;
728         ph->pipe_handle = pn->pipe_handle;
729         ph->data0 = PAD;
730         return pn_skb_send(sk, skb, NULL);
731 }
732 
733 /* associated socket ceases to exist */
734 static void pep_sock_close(struct sock *sk, long timeout)
735 {
736         struct pep_sock *pn = pep_sk(sk);
737         int ifindex = 0;
738 
739         sock_hold(sk); /* keep a reference after sk_common_release() */
740         sk_common_release(sk);
741 
742         lock_sock(sk);
743         if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) {
744                 if (sk->sk_backlog_rcv == pipe_do_rcv)
745                         /* Forcefully remove dangling Phonet pipe */
746                         pipe_do_remove(sk);
747                 else
748                         pipe_handler_request(sk, PNS_PEP_DISCONNECT_REQ, PAD,
749                                                 NULL, 0);
750         }
751         sk->sk_state = TCP_CLOSE;
752 
753         ifindex = pn->ifindex;
754         pn->ifindex = 0;
755         release_sock(sk);
756 
757         if (ifindex)
758                 gprs_detach(sk);
759         sock_put(sk);
760 }
761 
762 static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp,
763                                     bool kern)
764 {
765         struct pep_sock *pn = pep_sk(sk), *newpn;
766         struct sock *newsk = NULL;
767         struct sk_buff *skb;
768         struct pnpipehdr *hdr;
769         struct sockaddr_pn dst, src;
770         int err;
771         u16 peer_type;
772         u8 pipe_handle, enabled, n_sb;
773         u8 aligned = 0;
774 
775         skb = skb_recv_datagram(sk, 0, flags & O_NONBLOCK, errp);
776         if (!skb)
777                 return NULL;
778 
779         lock_sock(sk);
780         if (sk->sk_state != TCP_LISTEN) {
781                 err = -EINVAL;
782                 goto drop;
783         }
784         sk_acceptq_removed(sk);
785 
786         err = -EPROTO;
787         if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
788                 goto drop;
789 
790         hdr = pnp_hdr(skb);
791         pipe_handle = hdr->pipe_handle;
792         switch (hdr->state_after_connect) {
793         case PN_PIPE_DISABLE:
794                 enabled = 0;
795                 break;
796         case PN_PIPE_ENABLE:
797                 enabled = 1;
798                 break;
799         default:
800                 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM,
801                                 GFP_KERNEL);
802                 goto drop;
803         }
804         peer_type = hdr->other_pep_type << 8;
805 
806         /* Parse sub-blocks (options) */
807         n_sb = hdr->data[3];
808         while (n_sb > 0) {
809                 u8 type, buf[1], len = sizeof(buf);
810                 const u8 *data = pep_get_sb(skb, &type, &len, buf);
811 
812                 if (data == NULL)
813                         goto drop;
814                 switch (type) {
815                 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
816                         if (len < 1)
817                                 goto drop;
818                         peer_type = (peer_type & 0xff00) | data[0];
819                         break;
820                 case PN_PIPE_SB_ALIGNED_DATA:
821                         aligned = data[0] != 0;
822                         break;
823                 }
824                 n_sb--;
825         }
826 
827         /* Check for duplicate pipe handle */
828         newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
829         if (unlikely(newsk)) {
830                 __sock_put(newsk);
831                 newsk = NULL;
832                 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_KERNEL);
833                 goto drop;
834         }
835 
836         /* Create a new to-be-accepted sock */
837         newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_KERNEL, sk->sk_prot,
838                          kern);
839         if (!newsk) {
840                 pep_reject_conn(sk, skb, PN_PIPE_ERR_OVERLOAD, GFP_KERNEL);
841                 err = -ENOBUFS;
842                 goto drop;
843         }
844 
845         sock_init_data(NULL, newsk);
846         newsk->sk_state = TCP_SYN_RECV;
847         newsk->sk_backlog_rcv = pipe_do_rcv;
848         newsk->sk_protocol = sk->sk_protocol;
849         newsk->sk_destruct = pipe_destruct;
850 
851         newpn = pep_sk(newsk);
852         pn_skb_get_dst_sockaddr(skb, &dst);
853         pn_skb_get_src_sockaddr(skb, &src);
854         newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
855         newpn->pn_sk.dobject = pn_sockaddr_get_object(&src);
856         newpn->pn_sk.resource = pn_sockaddr_get_resource(&dst);
857         sock_hold(sk);
858         newpn->listener = sk;
859         skb_queue_head_init(&newpn->ctrlreq_queue);
860         newpn->pipe_handle = pipe_handle;
861         atomic_set(&newpn->tx_credits, 0);
862         newpn->ifindex = 0;
863         newpn->peer_type = peer_type;
864         newpn->rx_credits = 0;
865         newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
866         newpn->init_enable = enabled;
867         newpn->aligned = aligned;
868 
869         err = pep_accept_conn(newsk, skb);
870         if (err) {
871                 sock_put(newsk);
872                 newsk = NULL;
873                 goto drop;
874         }
875         sk_add_node(newsk, &pn->hlist);
876 drop:
877         release_sock(sk);
878         kfree_skb(skb);
879         *errp = err;
880         return newsk;
881 }
882 
883 static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len)
884 {
885         struct pep_sock *pn = pep_sk(sk);
886         int err;
887         u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD };
888 
889         if (pn->pipe_handle == PN_PIPE_INVALID_HANDLE)
890                 pn->pipe_handle = 1; /* anything but INVALID_HANDLE */
891 
892         err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ,
893                                 pn->init_enable, data, 4);
894         if (err) {
895                 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
896                 return err;
897         }
898 
899         sk->sk_state = TCP_SYN_SENT;
900 
901         return 0;
902 }
903 
904 static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len)
905 {
906         int err;
907 
908         err = pipe_handler_request(sk, PNS_PEP_ENABLE_REQ, PAD,
909                                 NULL, 0);
910         if (err)
911                 return err;
912 
913         sk->sk_state = TCP_SYN_SENT;
914 
915         return 0;
916 }
917 
918 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
919 {
920         struct pep_sock *pn = pep_sk(sk);
921         int answ;
922         int ret = -ENOIOCTLCMD;
923 
924         switch (cmd) {
925         case SIOCINQ:
926                 if (sk->sk_state == TCP_LISTEN) {
927                         ret = -EINVAL;
928                         break;
929                 }
930 
931                 lock_sock(sk);
932                 if (sock_flag(sk, SOCK_URGINLINE) &&
933                     !skb_queue_empty(&pn->ctrlreq_queue))
934                         answ = skb_peek(&pn->ctrlreq_queue)->len;
935                 else if (!skb_queue_empty(&sk->sk_receive_queue))
936                         answ = skb_peek(&sk->sk_receive_queue)->len;
937                 else
938                         answ = 0;
939                 release_sock(sk);
940                 ret = put_user(answ, (int __user *)arg);
941                 break;
942 
943         case SIOCPNENABLEPIPE:
944                 lock_sock(sk);
945                 if (sk->sk_state == TCP_SYN_SENT)
946                         ret =  -EBUSY;
947                 else if (sk->sk_state == TCP_ESTABLISHED)
948                         ret = -EISCONN;
949                 else
950                         ret = pep_sock_enable(sk, NULL, 0);
951                 release_sock(sk);
952                 break;
953         }
954 
955         return ret;
956 }
957 
958 static int pep_init(struct sock *sk)
959 {
960         struct pep_sock *pn = pep_sk(sk);
961 
962         sk->sk_destruct = pipe_destruct;
963         INIT_HLIST_HEAD(&pn->hlist);
964         pn->listener = NULL;
965         skb_queue_head_init(&pn->ctrlreq_queue);
966         atomic_set(&pn->tx_credits, 0);
967         pn->ifindex = 0;
968         pn->peer_type = 0;
969         pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
970         pn->rx_credits = 0;
971         pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
972         pn->init_enable = 1;
973         pn->aligned = 0;
974         return 0;
975 }
976 
977 static int pep_setsockopt(struct sock *sk, int level, int optname,
978                                 char __user *optval, unsigned int optlen)
979 {
980         struct pep_sock *pn = pep_sk(sk);
981         int val = 0, err = 0;
982 
983         if (level != SOL_PNPIPE)
984                 return -ENOPROTOOPT;
985         if (optlen >= sizeof(int)) {
986                 if (get_user(val, (int __user *) optval))
987                         return -EFAULT;
988         }
989 
990         lock_sock(sk);
991         switch (optname) {
992         case PNPIPE_ENCAP:
993                 if (val && val != PNPIPE_ENCAP_IP) {
994                         err = -EINVAL;
995                         break;
996                 }
997                 if (!pn->ifindex == !val)
998                         break; /* Nothing to do! */
999                 if (!capable(CAP_NET_ADMIN)) {
1000                         err = -EPERM;
1001                         break;
1002                 }
1003                 if (val) {
1004                         release_sock(sk);
1005                         err = gprs_attach(sk);
1006                         if (err > 0) {
1007                                 pn->ifindex = err;
1008                                 err = 0;
1009                         }
1010                 } else {
1011                         pn->ifindex = 0;
1012                         release_sock(sk);
1013                         gprs_detach(sk);
1014                         err = 0;
1015                 }
1016                 goto out_norel;
1017 
1018         case PNPIPE_HANDLE:
1019                 if ((sk->sk_state == TCP_CLOSE) &&
1020                         (val >= 0) && (val < PN_PIPE_INVALID_HANDLE))
1021                         pn->pipe_handle = val;
1022                 else
1023                         err = -EINVAL;
1024                 break;
1025 
1026         case PNPIPE_INITSTATE:
1027                 pn->init_enable = !!val;
1028                 break;
1029 
1030         default:
1031                 err = -ENOPROTOOPT;
1032         }
1033         release_sock(sk);
1034 
1035 out_norel:
1036         return err;
1037 }
1038 
1039 static int pep_getsockopt(struct sock *sk, int level, int optname,
1040                                 char __user *optval, int __user *optlen)
1041 {
1042         struct pep_sock *pn = pep_sk(sk);
1043         int len, val;
1044 
1045         if (level != SOL_PNPIPE)
1046                 return -ENOPROTOOPT;
1047         if (get_user(len, optlen))
1048                 return -EFAULT;
1049 
1050         switch (optname) {
1051         case PNPIPE_ENCAP:
1052                 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
1053                 break;
1054 
1055         case PNPIPE_IFINDEX:
1056                 val = pn->ifindex;
1057                 break;
1058 
1059         case PNPIPE_HANDLE:
1060                 val = pn->pipe_handle;
1061                 if (val == PN_PIPE_INVALID_HANDLE)
1062                         return -EINVAL;
1063                 break;
1064 
1065         case PNPIPE_INITSTATE:
1066                 val = pn->init_enable;
1067                 break;
1068 
1069         default:
1070                 return -ENOPROTOOPT;
1071         }
1072 
1073         len = min_t(unsigned int, sizeof(int), len);
1074         if (put_user(len, optlen))
1075                 return -EFAULT;
1076         if (put_user(val, (int __user *) optval))
1077                 return -EFAULT;
1078         return 0;
1079 }
1080 
1081 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
1082 {
1083         struct pep_sock *pn = pep_sk(sk);
1084         struct pnpipehdr *ph;
1085         int err;
1086 
1087         if (pn_flow_safe(pn->tx_fc) &&
1088             !atomic_add_unless(&pn->tx_credits, -1, 0)) {
1089                 kfree_skb(skb);
1090                 return -ENOBUFS;
1091         }
1092 
1093         skb_push(skb, 3 + pn->aligned);
1094         skb_reset_transport_header(skb);
1095         ph = pnp_hdr(skb);
1096         ph->utid = 0;
1097         if (pn->aligned) {
1098                 ph->message_id = PNS_PIPE_ALIGNED_DATA;
1099                 ph->data0 = 0; /* padding */
1100         } else
1101                 ph->message_id = PNS_PIPE_DATA;
1102         ph->pipe_handle = pn->pipe_handle;
1103         err = pn_skb_send(sk, skb, NULL);
1104 
1105         if (err && pn_flow_safe(pn->tx_fc))
1106                 atomic_inc(&pn->tx_credits);
1107         return err;
1108 
1109 }
1110 
1111 static int pep_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1112 {
1113         struct pep_sock *pn = pep_sk(sk);
1114         struct sk_buff *skb;
1115         long timeo;
1116         int flags = msg->msg_flags;
1117         int err, done;
1118 
1119         if (len > USHRT_MAX)
1120                 return -EMSGSIZE;
1121 
1122         if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
1123                                 MSG_CMSG_COMPAT)) ||
1124                         !(msg->msg_flags & MSG_EOR))
1125                 return -EOPNOTSUPP;
1126 
1127         skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
1128                                         flags & MSG_DONTWAIT, &err);
1129         if (!skb)
1130                 return err;
1131 
1132         skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned);
1133         err = memcpy_from_msg(skb_put(skb, len), msg, len);
1134         if (err < 0)
1135                 goto outfree;
1136 
1137         lock_sock(sk);
1138         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1139         if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
1140                 err = -ENOTCONN;
1141                 goto out;
1142         }
1143         if (sk->sk_state != TCP_ESTABLISHED) {
1144                 /* Wait until the pipe gets to enabled state */
1145 disabled:
1146                 err = sk_stream_wait_connect(sk, &timeo);
1147                 if (err)
1148                         goto out;
1149 
1150                 if (sk->sk_state == TCP_CLOSE_WAIT) {
1151                         err = -ECONNRESET;
1152                         goto out;
1153                 }
1154         }
1155         BUG_ON(sk->sk_state != TCP_ESTABLISHED);
1156 
1157         /* Wait until flow control allows TX */
1158         done = atomic_read(&pn->tx_credits);
1159         while (!done) {
1160                 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1161 
1162                 if (!timeo) {
1163                         err = -EAGAIN;
1164                         goto out;
1165                 }
1166                 if (signal_pending(current)) {
1167                         err = sock_intr_errno(timeo);
1168                         goto out;
1169                 }
1170 
1171                 add_wait_queue(sk_sleep(sk), &wait);
1172                 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits), &wait);
1173                 remove_wait_queue(sk_sleep(sk), &wait);
1174 
1175                 if (sk->sk_state != TCP_ESTABLISHED)
1176                         goto disabled;
1177         }
1178 
1179         err = pipe_skb_send(sk, skb);
1180         if (err >= 0)
1181                 err = len; /* success! */
1182         skb = NULL;
1183 out:
1184         release_sock(sk);
1185 outfree:
1186         kfree_skb(skb);
1187         return err;
1188 }
1189 
1190 int pep_writeable(struct sock *sk)
1191 {
1192         struct pep_sock *pn = pep_sk(sk);
1193 
1194         return atomic_read(&pn->tx_credits);
1195 }
1196 
1197 int pep_write(struct sock *sk, struct sk_buff *skb)
1198 {
1199         struct sk_buff *rskb, *fs;
1200         int flen = 0;
1201 
1202         if (pep_sk(sk)->aligned)
1203                 return pipe_skb_send(sk, skb);
1204 
1205         rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
1206         if (!rskb) {
1207                 kfree_skb(skb);
1208                 return -ENOMEM;
1209         }
1210         skb_shinfo(rskb)->frag_list = skb;
1211         rskb->len += skb->len;
1212         rskb->data_len += rskb->len;
1213         rskb->truesize += rskb->len;
1214 
1215         /* Avoid nested fragments */
1216         skb_walk_frags(skb, fs)
1217                 flen += fs->len;
1218         skb->next = skb_shinfo(skb)->frag_list;
1219         skb_frag_list_init(skb);
1220         skb->len -= flen;
1221         skb->data_len -= flen;
1222         skb->truesize -= flen;
1223 
1224         skb_reserve(rskb, MAX_PHONET_HEADER + 3);
1225         return pipe_skb_send(sk, rskb);
1226 }
1227 
1228 struct sk_buff *pep_read(struct sock *sk)
1229 {
1230         struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
1231 
1232         if (sk->sk_state == TCP_ESTABLISHED)
1233                 pipe_grant_credits(sk, GFP_ATOMIC);
1234         return skb;
1235 }
1236 
1237 static int pep_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
1238                        int noblock, int flags, int *addr_len)
1239 {
1240         struct sk_buff *skb;
1241         int err;
1242 
1243         if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
1244                         MSG_NOSIGNAL|MSG_CMSG_COMPAT))
1245                 return -EOPNOTSUPP;
1246 
1247         if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
1248                 return -ENOTCONN;
1249 
1250         if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
1251                 /* Dequeue and acknowledge control request */
1252                 struct pep_sock *pn = pep_sk(sk);
1253 
1254                 if (flags & MSG_PEEK)
1255                         return -EOPNOTSUPP;
1256                 skb = skb_dequeue(&pn->ctrlreq_queue);
1257                 if (skb) {
1258                         pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1259                                                 GFP_KERNEL);
1260                         msg->msg_flags |= MSG_OOB;
1261                         goto copy;
1262                 }
1263                 if (flags & MSG_OOB)
1264                         return -EINVAL;
1265         }
1266 
1267         skb = skb_recv_datagram(sk, flags, noblock, &err);
1268         lock_sock(sk);
1269         if (skb == NULL) {
1270                 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1271                         err = -ECONNRESET;
1272                 release_sock(sk);
1273                 return err;
1274         }
1275 
1276         if (sk->sk_state == TCP_ESTABLISHED)
1277                 pipe_grant_credits(sk, GFP_KERNEL);
1278         release_sock(sk);
1279 copy:
1280         msg->msg_flags |= MSG_EOR;
1281         if (skb->len > len)
1282                 msg->msg_flags |= MSG_TRUNC;
1283         else
1284                 len = skb->len;
1285 
1286         err = skb_copy_datagram_msg(skb, 0, msg, len);
1287         if (!err)
1288                 err = (flags & MSG_TRUNC) ? skb->len : len;
1289 
1290         skb_free_datagram(sk, skb);
1291         return err;
1292 }
1293 
1294 static void pep_sock_unhash(struct sock *sk)
1295 {
1296         struct pep_sock *pn = pep_sk(sk);
1297         struct sock *skparent = NULL;
1298 
1299         lock_sock(sk);
1300 
1301         if (pn->listener != NULL) {
1302                 skparent = pn->listener;
1303                 pn->listener = NULL;
1304                 release_sock(sk);
1305 
1306                 pn = pep_sk(skparent);
1307                 lock_sock(skparent);
1308                 sk_del_node_init(sk);
1309                 sk = skparent;
1310         }
1311 
1312         /* Unhash a listening sock only when it is closed
1313          * and all of its active connected pipes are closed. */
1314         if (hlist_empty(&pn->hlist))
1315                 pn_sock_unhash(&pn->pn_sk.sk);
1316         release_sock(sk);
1317 
1318         if (skparent)
1319                 sock_put(skparent);
1320 }
1321 
1322 static struct proto pep_proto = {
1323         .close          = pep_sock_close,
1324         .accept         = pep_sock_accept,
1325         .connect        = pep_sock_connect,
1326         .ioctl          = pep_ioctl,
1327         .init           = pep_init,
1328         .setsockopt     = pep_setsockopt,
1329         .getsockopt     = pep_getsockopt,
1330         .sendmsg        = pep_sendmsg,
1331         .recvmsg        = pep_recvmsg,
1332         .backlog_rcv    = pep_do_rcv,
1333         .hash           = pn_sock_hash,
1334         .unhash         = pep_sock_unhash,
1335         .get_port       = pn_sock_get_port,
1336         .obj_size       = sizeof(struct pep_sock),
1337         .owner          = THIS_MODULE,
1338         .name           = "PNPIPE",
1339 };
1340 
1341 static const struct phonet_protocol pep_pn_proto = {
1342         .ops            = &phonet_stream_ops,
1343         .prot           = &pep_proto,
1344         .sock_type      = SOCK_SEQPACKET,
1345 };
1346 
1347 static int __init pep_register(void)
1348 {
1349         return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1350 }
1351 
1352 static void __exit pep_unregister(void)
1353 {
1354         phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1355 }
1356 
1357 module_init(pep_register);
1358 module_exit(pep_unregister);
1359 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1360 MODULE_DESCRIPTION("Phonet pipe protocol");
1361 MODULE_LICENSE("GPL");
1362 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);
1363 

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