?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
writeback: split writeback_inodes_wb
[linux-2.6/next.git] / net / phonet / pep.c
blob94d72e85a475ae094d14f8df5f4f54a936f0db15
1 /*
2 * File: pep.c
3 *
4 * Phonet pipe protocol end point socket
5 *
6 * Copyright (C) 2008 Nokia Corporation.
7 *
8 * Author: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
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 <net/phonet/phonet.h>
34 #include <net/phonet/pep.h>
35 #include <net/phonet/gprs.h>
36
37 /* sk_state values:
38 * TCP_CLOSE sock not in use yet
39 * TCP_CLOSE_WAIT disconnected pipe
40 * TCP_LISTEN listening pipe endpoint
41 * TCP_SYN_RECV connected pipe in disabled state
42 * TCP_ESTABLISHED connected pipe in enabled state
43 *
44 * pep_sock locking:
45 * - sk_state, ackq, hlist: sock lock needed
46 * - listener: read only
47 * - pipe_handle: read only
48 */
49
50 #define CREDITS_MAX 10
51 #define CREDITS_THR 7
52
53 static const struct sockaddr_pn pipe_srv = {
54 .spn_family = AF_PHONET,
55 .spn_resource = 0xD9, /* pipe service */
56 };
57
58 #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */
59
60 /* Get the next TLV sub-block. */
61 static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen,
62 void *buf)
63 {
64 void *data = NULL;
65 struct {
66 u8 sb_type;
67 u8 sb_len;
68 } *ph, h;
69 int buflen = *plen;
70
71 ph = skb_header_pointer(skb, 0, 2, &h);
72 if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len))
73 return NULL;
74 ph->sb_len -= 2;
75 *ptype = ph->sb_type;
76 *plen = ph->sb_len;
77
78 if (buflen > ph->sb_len)
79 buflen = ph->sb_len;
80 data = skb_header_pointer(skb, 2, buflen, buf);
81 __skb_pull(skb, 2 + ph->sb_len);
82 return data;
83 }
84
85 static int pep_reply(struct sock *sk, struct sk_buff *oskb,
86 u8 code, 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
92 skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority);
93 if (!skb)
94 return -ENOMEM;
95 skb_set_owner_w(skb, sk);
96
97 skb_reserve(skb, MAX_PNPIPE_HEADER);
98 __skb_put(skb, len);
99 skb_copy_to_linear_data(skb, data, len);
100 __skb_push(skb, sizeof(*ph));
101 skb_reset_transport_header(skb);
102 ph = pnp_hdr(skb);
103 ph->utid = oph->utid;
104 ph->message_id = oph->message_id + 1; /* REQ -> RESP */
105 ph->pipe_handle = oph->pipe_handle;
106 ph->error_code = code;
107
108 return pn_skb_send(sk, skb, &pipe_srv);
109 }
110
111 #define PAD 0x00
112 static int pep_accept_conn(struct sock *sk, struct sk_buff *skb)
113 {
114 static const u8 data[20] = {
115 PAD, PAD, PAD, 2 /* sub-blocks */,
116 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD,
117 PN_MULTI_CREDIT_FLOW_CONTROL,
118 PN_ONE_CREDIT_FLOW_CONTROL,
119 PN_LEGACY_FLOW_CONTROL,
120 PAD,
121 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD,
122 PN_MULTI_CREDIT_FLOW_CONTROL,
123 PN_ONE_CREDIT_FLOW_CONTROL,
124 PN_LEGACY_FLOW_CONTROL,
125 PAD,
126 };
127
128 might_sleep();
129 return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data),
130 GFP_KERNEL);
131 }
132
133 static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code)
134 {
135 static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ };
136 WARN_ON(code == PN_PIPE_NO_ERROR);
137 return pep_reply(sk, skb, code, data, sizeof(data), GFP_ATOMIC);
138 }
139
140 /* Control requests are not sent by the pipe service and have a specific
141 * message format. */
142 static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
143 gfp_t priority)
144 {
145 const struct pnpipehdr *oph = pnp_hdr(oskb);
146 struct sk_buff *skb;
147 struct pnpipehdr *ph;
148 struct sockaddr_pn dst;
149
150 skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority);
151 if (!skb)
152 return -ENOMEM;
153 skb_set_owner_w(skb, sk);
154
155 skb_reserve(skb, MAX_PHONET_HEADER);
156 ph = (struct pnpipehdr *)skb_put(skb, sizeof(*ph) + 4);
157
158 ph->utid = oph->utid;
159 ph->message_id = PNS_PEP_CTRL_RESP;
160 ph->pipe_handle = oph->pipe_handle;
161 ph->data[0] = oph->data[1]; /* CTRL id */
162 ph->data[1] = oph->data[0]; /* PEP type */
163 ph->data[2] = code; /* error code, at an usual offset */
164 ph->data[3] = PAD;
165 ph->data[4] = PAD;
166
167 pn_skb_get_src_sockaddr(oskb, &dst);
168 return pn_skb_send(sk, skb, &dst);
169 }
170
171 static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority)
172 {
173 struct pep_sock *pn = pep_sk(sk);
174 struct pnpipehdr *ph;
175 struct sk_buff *skb;
176
177 skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority);
178 if (!skb)
179 return -ENOMEM;
180 skb_set_owner_w(skb, sk);
181
182 skb_reserve(skb, MAX_PNPIPE_HEADER + 4);
183 __skb_push(skb, sizeof(*ph) + 4);
184 skb_reset_transport_header(skb);
185 ph = pnp_hdr(skb);
186 ph->utid = 0;
187 ph->message_id = PNS_PEP_STATUS_IND;
188 ph->pipe_handle = pn->pipe_handle;
189 ph->pep_type = PN_PEP_TYPE_COMMON;
190 ph->data[1] = type;
191 ph->data[2] = PAD;
192 ph->data[3] = PAD;
193 ph->data[4] = status;
194
195 return pn_skb_send(sk, skb, &pipe_srv);
196 }
197
198 /* Send our RX flow control information to the sender.
199 * Socket must be locked. */
200 static void pipe_grant_credits(struct sock *sk)
201 {
202 struct pep_sock *pn = pep_sk(sk);
203
204 BUG_ON(sk->sk_state != TCP_ESTABLISHED);
205
206 switch (pn->rx_fc) {
207 case PN_LEGACY_FLOW_CONTROL: /* TODO */
208 break;
209 case PN_ONE_CREDIT_FLOW_CONTROL:
210 pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL,
211 PEP_IND_READY, GFP_ATOMIC);
212 pn->rx_credits = 1;
213 break;
214 case PN_MULTI_CREDIT_FLOW_CONTROL:
215 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX)
216 break;
217 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
218 CREDITS_MAX - pn->rx_credits,
219 GFP_ATOMIC) == 0)
220 pn->rx_credits = CREDITS_MAX;
221 break;
222 }
223 }
224
225 static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
226 {
227 struct pep_sock *pn = pep_sk(sk);
228 struct pnpipehdr *hdr = pnp_hdr(skb);
229 int wake = 0;
230
231 if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
232 return -EINVAL;
233
234 if (hdr->data[0] != PN_PEP_TYPE_COMMON) {
235 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n",
236 (unsigned)hdr->data[0]);
237 return -EOPNOTSUPP;
238 }
239
240 switch (hdr->data[1]) {
241 case PN_PEP_IND_FLOW_CONTROL:
242 switch (pn->tx_fc) {
243 case PN_LEGACY_FLOW_CONTROL:
244 switch (hdr->data[4]) {
245 case PEP_IND_BUSY:
246 atomic_set(&pn->tx_credits, 0);
247 break;
248 case PEP_IND_READY:
249 atomic_set(&pn->tx_credits, wake = 1);
250 break;
251 }
252 break;
253 case PN_ONE_CREDIT_FLOW_CONTROL:
254 if (hdr->data[4] == PEP_IND_READY)
255 atomic_set(&pn->tx_credits, wake = 1);
256 break;
257 }
258 break;
259
260 case PN_PEP_IND_ID_MCFC_GRANT_CREDITS:
261 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL)
262 break;
263 atomic_add(wake = hdr->data[4], &pn->tx_credits);
264 break;
265
266 default:
267 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n",
268 (unsigned)hdr->data[1]);
269 return -EOPNOTSUPP;
270 }
271 if (wake)
272 sk->sk_write_space(sk);
273 return 0;
274 }
275
276 static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb)
277 {
278 struct pep_sock *pn = pep_sk(sk);
279 struct pnpipehdr *hdr = pnp_hdr(skb);
280 u8 n_sb = hdr->data[0];
281
282 pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
283 __skb_pull(skb, sizeof(*hdr));
284 while (n_sb > 0) {
285 u8 type, buf[2], len = sizeof(buf);
286 u8 *data = pep_get_sb(skb, &type, &len, buf);
287
288 if (data == NULL)
289 return -EINVAL;
290 switch (type) {
291 case PN_PIPE_SB_NEGOTIATED_FC:
292 if (len < 2 || (data[0] | data[1]) > 3)
293 break;
294 pn->tx_fc = data[0] & 3;
295 pn->rx_fc = data[1] & 3;
296 break;
297 }
298 n_sb--;
299 }
300 return 0;
301 }
302
303 /* Queue an skb to a connected sock.
304 * Socket lock must be held. */
305 static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
306 {
307 struct pep_sock *pn = pep_sk(sk);
308 struct pnpipehdr *hdr = pnp_hdr(skb);
309 struct sk_buff_head *queue;
310 int err = 0;
311
312 BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
313
314 switch (hdr->message_id) {
315 case PNS_PEP_CONNECT_REQ:
316 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE);
317 break;
318
319 case PNS_PEP_DISCONNECT_REQ:
320 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
321 sk->sk_state = TCP_CLOSE_WAIT;
322 if (!sock_flag(sk, SOCK_DEAD))
323 sk->sk_state_change(sk);
324 break;
325
326 case PNS_PEP_ENABLE_REQ:
327 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */
328 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
329 break;
330
331 case PNS_PEP_RESET_REQ:
332 switch (hdr->state_after_reset) {
333 case PN_PIPE_DISABLE:
334 pn->init_enable = 0;
335 break;
336 case PN_PIPE_ENABLE:
337 pn->init_enable = 1;
338 break;
339 default: /* not allowed to send an error here!? */
340 err = -EINVAL;
341 goto out;
342 }
343 /* fall through */
344 case PNS_PEP_DISABLE_REQ:
345 atomic_set(&pn->tx_credits, 0);
346 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
347 break;
348
349 case PNS_PEP_CTRL_REQ:
350 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) {
351 atomic_inc(&sk->sk_drops);
352 break;
353 }
354 __skb_pull(skb, 4);
355 queue = &pn->ctrlreq_queue;
356 goto queue;
357
358 case PNS_PIPE_ALIGNED_DATA:
359 __skb_pull(skb, 1);
360 /* fall through */
361 case PNS_PIPE_DATA:
362 __skb_pull(skb, 3); /* Pipe data header */
363 if (!pn_flow_safe(pn->rx_fc)) {
364 err = sock_queue_rcv_skb(sk, skb);
365 if (!err)
366 return 0;
367 break;
368 }
369
370 if (pn->rx_credits == 0) {
371 atomic_inc(&sk->sk_drops);
372 err = -ENOBUFS;
373 break;
374 }
375 pn->rx_credits--;
376 queue = &sk->sk_receive_queue;
377 goto queue;
378
379 case PNS_PEP_STATUS_IND:
380 pipe_rcv_status(sk, skb);
381 break;
382
383 case PNS_PIPE_REDIRECTED_IND:
384 err = pipe_rcv_created(sk, skb);
385 break;
386
387 case PNS_PIPE_CREATED_IND:
388 err = pipe_rcv_created(sk, skb);
389 if (err)
390 break;
391 /* fall through */
392 case PNS_PIPE_RESET_IND:
393 if (!pn->init_enable)
394 break;
395 /* fall through */
396 case PNS_PIPE_ENABLED_IND:
397 if (!pn_flow_safe(pn->tx_fc)) {
398 atomic_set(&pn->tx_credits, 1);
399 sk->sk_write_space(sk);
400 }
401 if (sk->sk_state == TCP_ESTABLISHED)
402 break; /* Nothing to do */
403 sk->sk_state = TCP_ESTABLISHED;
404 pipe_grant_credits(sk);
405 break;
406
407 case PNS_PIPE_DISABLED_IND:
408 sk->sk_state = TCP_SYN_RECV;
409 pn->rx_credits = 0;
410 break;
411
412 default:
413 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n",
414 hdr->message_id);
415 err = -EINVAL;
416 }
417 out:
418 kfree_skb(skb);
419 return err;
420
421 queue:
422 skb->dev = NULL;
423 skb_set_owner_r(skb, sk);
424 err = skb->len;
425 skb_queue_tail(queue, skb);
426 if (!sock_flag(sk, SOCK_DEAD))
427 sk->sk_data_ready(sk, err);
428 return 0;
429 }
430
431 /* Destroy connected sock. */
432 static void pipe_destruct(struct sock *sk)
433 {
434 struct pep_sock *pn = pep_sk(sk);
435
436 skb_queue_purge(&sk->sk_receive_queue);
437 skb_queue_purge(&pn->ctrlreq_queue);
438 }
439
440 static int pep_connreq_rcv(struct sock *sk, struct sk_buff *skb)
441 {
442 struct sock *newsk;
443 struct pep_sock *newpn, *pn = pep_sk(sk);
444 struct pnpipehdr *hdr;
445 struct sockaddr_pn dst;
446 u16 peer_type;
447 u8 pipe_handle, enabled, n_sb;
448 u8 aligned = 0;
449
450 if (!pskb_pull(skb, sizeof(*hdr) + 4))
451 return -EINVAL;
452
453 hdr = pnp_hdr(skb);
454 pipe_handle = hdr->pipe_handle;
455 switch (hdr->state_after_connect) {
456 case PN_PIPE_DISABLE:
457 enabled = 0;
458 break;
459 case PN_PIPE_ENABLE:
460 enabled = 1;
461 break;
462 default:
463 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM);
464 return -EINVAL;
465 }
466 peer_type = hdr->other_pep_type << 8;
467
468 if (unlikely(sk->sk_state != TCP_LISTEN) || sk_acceptq_is_full(sk)) {
469 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE);
470 return -ENOBUFS;
471 }
472
473 /* Parse sub-blocks (options) */
474 n_sb = hdr->data[4];
475 while (n_sb > 0) {
476 u8 type, buf[1], len = sizeof(buf);
477 const u8 *data = pep_get_sb(skb, &type, &len, buf);
478
479 if (data == NULL)
480 return -EINVAL;
481 switch (type) {
482 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
483 if (len < 1)
484 return -EINVAL;
485 peer_type = (peer_type & 0xff00) | data[0];
486 break;
487 case PN_PIPE_SB_ALIGNED_DATA:
488 aligned = data[0] != 0;
489 break;
490 }
491 n_sb--;
492 }
493
494 skb = skb_clone(skb, GFP_ATOMIC);
495 if (!skb)
496 return -ENOMEM;
497
498 /* Create a new to-be-accepted sock */
499 newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_ATOMIC, sk->sk_prot);
500 if (!newsk) {
501 kfree_skb(skb);
502 return -ENOMEM;
503 }
504 sock_init_data(NULL, newsk);
505 newsk->sk_state = TCP_SYN_RECV;
506 newsk->sk_backlog_rcv = pipe_do_rcv;
507 newsk->sk_protocol = sk->sk_protocol;
508 newsk->sk_destruct = pipe_destruct;
509
510 newpn = pep_sk(newsk);
511 pn_skb_get_dst_sockaddr(skb, &dst);
512 newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
513 newpn->pn_sk.resource = pn->pn_sk.resource;
514 skb_queue_head_init(&newpn->ctrlreq_queue);
515 newpn->pipe_handle = pipe_handle;
516 atomic_set(&newpn->tx_credits, 0);
517 newpn->peer_type = peer_type;
518 newpn->rx_credits = 0;
519 newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
520 newpn->init_enable = enabled;
521 newpn->aligned = aligned;
522
523 BUG_ON(!skb_queue_empty(&newsk->sk_receive_queue));
524 skb_queue_head(&newsk->sk_receive_queue, skb);
525 if (!sock_flag(sk, SOCK_DEAD))
526 sk->sk_data_ready(sk, 0);
527
528 sk_acceptq_added(sk);
529 sk_add_node(newsk, &pn->ackq);
530 return 0;
531 }
532
533 /* Listening sock must be locked */
534 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
535 const struct sockaddr_pn *dst,
536 u8 pipe_handle)
537 {
538 struct hlist_node *node;
539 struct sock *sknode;
540 u16 dobj = pn_sockaddr_get_object(dst);
541
542 sk_for_each(sknode, node, hlist) {
543 struct pep_sock *pnnode = pep_sk(sknode);
544
545 /* Ports match, but addresses might not: */
546 if (pnnode->pn_sk.sobject != dobj)
547 continue;
548 if (pnnode->pipe_handle != pipe_handle)
549 continue;
550 if (sknode->sk_state == TCP_CLOSE_WAIT)
551 continue;
552
553 sock_hold(sknode);
554 return sknode;
555 }
556 return NULL;
557 }
558
559 /*
560 * Deliver an skb to a listening sock.
561 * Socket lock must be held.
562 * We then queue the skb to the right connected sock (if any).
563 */
564 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
565 {
566 struct pep_sock *pn = pep_sk(sk);
567 struct sock *sknode;
568 struct pnpipehdr *hdr;
569 struct sockaddr_pn dst;
570 int err = NET_RX_SUCCESS;
571 u8 pipe_handle;
572
573 if (!pskb_may_pull(skb, sizeof(*hdr)))
574 goto drop;
575
576 hdr = pnp_hdr(skb);
577 pipe_handle = hdr->pipe_handle;
578 if (pipe_handle == PN_PIPE_INVALID_HANDLE)
579 goto drop;
580
581 pn_skb_get_dst_sockaddr(skb, &dst);
582
583 /* Look for an existing pipe handle */
584 sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
585 if (sknode)
586 return sk_receive_skb(sknode, skb, 1);
587
588 /* Look for a pipe handle pending accept */
589 sknode = pep_find_pipe(&pn->ackq, &dst, pipe_handle);
590 if (sknode) {
591 sock_put(sknode);
592 if (net_ratelimit())
593 printk(KERN_WARNING"Phonet unconnected PEP ignored");
594 err = NET_RX_DROP;
595 goto drop;
596 }
597
598 switch (hdr->message_id) {
599 case PNS_PEP_CONNECT_REQ:
600 err = pep_connreq_rcv(sk, skb);
601 break;
602
603 case PNS_PEP_DISCONNECT_REQ:
604 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
605 break;
606
607 case PNS_PEP_CTRL_REQ:
608 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
609 break;
610
611 case PNS_PEP_RESET_REQ:
612 case PNS_PEP_ENABLE_REQ:
613 case PNS_PEP_DISABLE_REQ:
614 /* invalid handle is not even allowed here! */
615 default:
616 err = NET_RX_DROP;
617 }
618 drop:
619 kfree_skb(skb);
620 return err;
621 }
622
623 /* associated socket ceases to exist */
624 static void pep_sock_close(struct sock *sk, long timeout)
625 {
626 struct pep_sock *pn = pep_sk(sk);
627 int ifindex = 0;
628
629 sock_hold(sk); /* keep a reference after sk_common_release() */
630 sk_common_release(sk);
631
632 lock_sock(sk);
633 if (sk->sk_state == TCP_LISTEN) {
634 /* Destroy the listen queue */
635 struct sock *sknode;
636 struct hlist_node *p, *n;
637
638 sk_for_each_safe(sknode, p, n, &pn->ackq)
639 sk_del_node_init(sknode);
640 sk->sk_state = TCP_CLOSE;
641 }
642 ifindex = pn->ifindex;
643 pn->ifindex = 0;
644 release_sock(sk);
645
646 if (ifindex)
647 gprs_detach(sk);
648 sock_put(sk);
649 }
650
651 static int pep_wait_connreq(struct sock *sk, int noblock)
652 {
653 struct task_struct *tsk = current;
654 struct pep_sock *pn = pep_sk(sk);
655 long timeo = sock_rcvtimeo(sk, noblock);
656
657 for (;;) {
658 DEFINE_WAIT(wait);
659
660 if (sk->sk_state != TCP_LISTEN)
661 return -EINVAL;
662 if (!hlist_empty(&pn->ackq))
663 break;
664 if (!timeo)
665 return -EWOULDBLOCK;
666 if (signal_pending(tsk))
667 return sock_intr_errno(timeo);
668
669 prepare_to_wait_exclusive(sk_sleep(sk), &wait,
670 TASK_INTERRUPTIBLE);
671 release_sock(sk);
672 timeo = schedule_timeout(timeo);
673 lock_sock(sk);
674 finish_wait(sk_sleep(sk), &wait);
675 }
676
677 return 0;
678 }
679
680 static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp)
681 {
682 struct pep_sock *pn = pep_sk(sk);
683 struct sock *newsk = NULL;
684 struct sk_buff *oskb;
685 int err;
686
687 lock_sock(sk);
688 err = pep_wait_connreq(sk, flags & O_NONBLOCK);
689 if (err)
690 goto out;
691
692 newsk = __sk_head(&pn->ackq);
693
694 oskb = skb_dequeue(&newsk->sk_receive_queue);
695 err = pep_accept_conn(newsk, oskb);
696 if (err) {
697 skb_queue_head(&newsk->sk_receive_queue, oskb);
698 newsk = NULL;
699 goto out;
700 }
701
702 sock_hold(sk);
703 pep_sk(newsk)->listener = sk;
704
705 sock_hold(newsk);
706 sk_del_node_init(newsk);
707 sk_acceptq_removed(sk);
708 sk_add_node(newsk, &pn->hlist);
709 __sock_put(newsk);
710
711 out:
712 release_sock(sk);
713 *errp = err;
714 return newsk;
715 }
716
717 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
718 {
719 struct pep_sock *pn = pep_sk(sk);
720 int answ;
721
722 switch (cmd) {
723 case SIOCINQ:
724 if (sk->sk_state == TCP_LISTEN)
725 return -EINVAL;
726
727 lock_sock(sk);
728 if (sock_flag(sk, SOCK_URGINLINE) &&
729 !skb_queue_empty(&pn->ctrlreq_queue))
730 answ = skb_peek(&pn->ctrlreq_queue)->len;
731 else if (!skb_queue_empty(&sk->sk_receive_queue))
732 answ = skb_peek(&sk->sk_receive_queue)->len;
733 else
734 answ = 0;
735 release_sock(sk);
736 return put_user(answ, (int __user *)arg);
737 }
738
739 return -ENOIOCTLCMD;
740 }
741
742 static int pep_init(struct sock *sk)
743 {
744 struct pep_sock *pn = pep_sk(sk);
745
746 INIT_HLIST_HEAD(&pn->ackq);
747 INIT_HLIST_HEAD(&pn->hlist);
748 skb_queue_head_init(&pn->ctrlreq_queue);
749 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
750 return 0;
751 }
752
753 static int pep_setsockopt(struct sock *sk, int level, int optname,
754 char __user *optval, unsigned int optlen)
755 {
756 struct pep_sock *pn = pep_sk(sk);
757 int val = 0, err = 0;
758
759 if (level != SOL_PNPIPE)
760 return -ENOPROTOOPT;
761 if (optlen >= sizeof(int)) {
762 if (get_user(val, (int __user *) optval))
763 return -EFAULT;
764 }
765
766 lock_sock(sk);
767 switch (optname) {
768 case PNPIPE_ENCAP:
769 if (val && val != PNPIPE_ENCAP_IP) {
770 err = -EINVAL;
771 break;
772 }
773 if (!pn->ifindex == !val)
774 break; /* Nothing to do! */
775 if (!capable(CAP_NET_ADMIN)) {
776 err = -EPERM;
777 break;
778 }
779 if (val) {
780 release_sock(sk);
781 err = gprs_attach(sk);
782 if (err > 0) {
783 pn->ifindex = err;
784 err = 0;
785 }
786 } else {
787 pn->ifindex = 0;
788 release_sock(sk);
789 gprs_detach(sk);
790 err = 0;
791 }
792 goto out_norel;
793 default:
794 err = -ENOPROTOOPT;
795 }
796 release_sock(sk);
797
798 out_norel:
799 return err;
800 }
801
802 static int pep_getsockopt(struct sock *sk, int level, int optname,
803 char __user *optval, int __user *optlen)
804 {
805 struct pep_sock *pn = pep_sk(sk);
806 int len, val;
807
808 if (level != SOL_PNPIPE)
809 return -ENOPROTOOPT;
810 if (get_user(len, optlen))
811 return -EFAULT;
812
813 switch (optname) {
814 case PNPIPE_ENCAP:
815 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
816 break;
817 case PNPIPE_IFINDEX:
818 val = pn->ifindex;
819 break;
820 default:
821 return -ENOPROTOOPT;
822 }
823
824 len = min_t(unsigned int, sizeof(int), len);
825 if (put_user(len, optlen))
826 return -EFAULT;
827 if (put_user(val, (int __user *) optval))
828 return -EFAULT;
829 return 0;
830 }
831
832 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
833 {
834 struct pep_sock *pn = pep_sk(sk);
835 struct pnpipehdr *ph;
836
837 if (pn_flow_safe(pn->tx_fc) &&
838 !atomic_add_unless(&pn->tx_credits, -1, 0)) {
839 kfree_skb(skb);
840 return -ENOBUFS;
841 }
842
843 skb_push(skb, 3 + pn->aligned);
844 skb_reset_transport_header(skb);
845 ph = pnp_hdr(skb);
846 ph->utid = 0;
847 if (pn->aligned) {
848 ph->message_id = PNS_PIPE_ALIGNED_DATA;
849 ph->data[0] = 0; /* padding */
850 } else
851 ph->message_id = PNS_PIPE_DATA;
852 ph->pipe_handle = pn->pipe_handle;
853
854 return pn_skb_send(sk, skb, &pipe_srv);
855 }
856
857 static int pep_sendmsg(struct kiocb *iocb, struct sock *sk,
858 struct msghdr *msg, size_t len)
859 {
860 struct pep_sock *pn = pep_sk(sk);
861 struct sk_buff *skb;
862 long timeo;
863 int flags = msg->msg_flags;
864 int err, done;
865
866 if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
867 MSG_CMSG_COMPAT)) ||
868 !(msg->msg_flags & MSG_EOR))
869 return -EOPNOTSUPP;
870
871 skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
872 flags & MSG_DONTWAIT, &err);
873 if (!skb)
874 return -ENOBUFS;
875
876 skb_reserve(skb, MAX_PHONET_HEADER + 3);
877 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
878 if (err < 0)
879 goto outfree;
880
881 lock_sock(sk);
882 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
883 if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
884 err = -ENOTCONN;
885 goto out;
886 }
887 if (sk->sk_state != TCP_ESTABLISHED) {
888 /* Wait until the pipe gets to enabled state */
889 disabled:
890 err = sk_stream_wait_connect(sk, &timeo);
891 if (err)
892 goto out;
893
894 if (sk->sk_state == TCP_CLOSE_WAIT) {
895 err = -ECONNRESET;
896 goto out;
897 }
898 }
899 BUG_ON(sk->sk_state != TCP_ESTABLISHED);
900
901 /* Wait until flow control allows TX */
902 done = atomic_read(&pn->tx_credits);
903 while (!done) {
904 DEFINE_WAIT(wait);
905
906 if (!timeo) {
907 err = -EAGAIN;
908 goto out;
909 }
910 if (signal_pending(current)) {
911 err = sock_intr_errno(timeo);
912 goto out;
913 }
914
915 prepare_to_wait(sk_sleep(sk), &wait,
916 TASK_INTERRUPTIBLE);
917 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits));
918 finish_wait(sk_sleep(sk), &wait);
919
920 if (sk->sk_state != TCP_ESTABLISHED)
921 goto disabled;
922 }
923
924 err = pipe_skb_send(sk, skb);
925 if (err >= 0)
926 err = len; /* success! */
927 skb = NULL;
928 out:
929 release_sock(sk);
930 outfree:
931 kfree_skb(skb);
932 return err;
933 }
934
935 int pep_writeable(struct sock *sk)
936 {
937 struct pep_sock *pn = pep_sk(sk);
938
939 return atomic_read(&pn->tx_credits);
940 }
941
942 int pep_write(struct sock *sk, struct sk_buff *skb)
943 {
944 struct sk_buff *rskb, *fs;
945 int flen = 0;
946
947 if (pep_sk(sk)->aligned)
948 return pipe_skb_send(sk, skb);
949
950 rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
951 if (!rskb) {
952 kfree_skb(skb);
953 return -ENOMEM;
954 }
955 skb_shinfo(rskb)->frag_list = skb;
956 rskb->len += skb->len;
957 rskb->data_len += rskb->len;
958 rskb->truesize += rskb->len;
959
960 /* Avoid nested fragments */
961 skb_walk_frags(skb, fs)
962 flen += fs->len;
963 skb->next = skb_shinfo(skb)->frag_list;
964 skb_frag_list_init(skb);
965 skb->len -= flen;
966 skb->data_len -= flen;
967 skb->truesize -= flen;
968
969 skb_reserve(rskb, MAX_PHONET_HEADER + 3);
970 return pipe_skb_send(sk, rskb);
971 }
972
973 struct sk_buff *pep_read(struct sock *sk)
974 {
975 struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
976
977 if (sk->sk_state == TCP_ESTABLISHED)
978 pipe_grant_credits(sk);
979 return skb;
980 }
981
982 static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
983 struct msghdr *msg, size_t len, int noblock,
984 int flags, int *addr_len)
985 {
986 struct sk_buff *skb;
987 int err;
988
989 if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
990 MSG_NOSIGNAL|MSG_CMSG_COMPAT))
991 return -EOPNOTSUPP;
992
993 if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
994 return -ENOTCONN;
995
996 if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
997 /* Dequeue and acknowledge control request */
998 struct pep_sock *pn = pep_sk(sk);
999
1000 if (flags & MSG_PEEK)
1001 return -EOPNOTSUPP;
1002 skb = skb_dequeue(&pn->ctrlreq_queue);
1003 if (skb) {
1004 pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1005 GFP_KERNEL);
1006 msg->msg_flags |= MSG_OOB;
1007 goto copy;
1008 }
1009 if (flags & MSG_OOB)
1010 return -EINVAL;
1011 }
1012
1013 skb = skb_recv_datagram(sk, flags, noblock, &err);
1014 lock_sock(sk);
1015 if (skb == NULL) {
1016 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1017 err = -ECONNRESET;
1018 release_sock(sk);
1019 return err;
1020 }
1021
1022 if (sk->sk_state == TCP_ESTABLISHED)
1023 pipe_grant_credits(sk);
1024 release_sock(sk);
1025 copy:
1026 msg->msg_flags |= MSG_EOR;
1027 if (skb->len > len)
1028 msg->msg_flags |= MSG_TRUNC;
1029 else
1030 len = skb->len;
1031
1032 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
1033 if (!err)
1034 err = (flags & MSG_TRUNC) ? skb->len : len;
1035
1036 skb_free_datagram(sk, skb);
1037 return err;
1038 }
1039
1040 static void pep_sock_unhash(struct sock *sk)
1041 {
1042 struct pep_sock *pn = pep_sk(sk);
1043 struct sock *skparent = NULL;
1044
1045 lock_sock(sk);
1046 if ((1 << sk->sk_state) & ~(TCPF_CLOSE|TCPF_LISTEN)) {
1047 skparent = pn->listener;
1048 release_sock(sk);
1049
1050 pn = pep_sk(skparent);
1051 lock_sock(skparent);
1052 sk_del_node_init(sk);
1053 sk = skparent;
1054 }
1055 /* Unhash a listening sock only when it is closed
1056 * and all of its active connected pipes are closed. */
1057 if (hlist_empty(&pn->hlist))
1058 pn_sock_unhash(&pn->pn_sk.sk);
1059 release_sock(sk);
1060
1061 if (skparent)
1062 sock_put(skparent);
1063 }
1064
1065 static struct proto pep_proto = {
1066 .close = pep_sock_close,
1067 .accept = pep_sock_accept,
1068 .ioctl = pep_ioctl,
1069 .init = pep_init,
1070 .setsockopt = pep_setsockopt,
1071 .getsockopt = pep_getsockopt,
1072 .sendmsg = pep_sendmsg,
1073 .recvmsg = pep_recvmsg,
1074 .backlog_rcv = pep_do_rcv,
1075 .hash = pn_sock_hash,
1076 .unhash = pep_sock_unhash,
1077 .get_port = pn_sock_get_port,
1078 .obj_size = sizeof(struct pep_sock),
1079 .owner = THIS_MODULE,
1080 .name = "PNPIPE",
1081 };
1082
1083 static struct phonet_protocol pep_pn_proto = {
1084 .ops = &phonet_stream_ops,
1085 .prot = &pep_proto,
1086 .sock_type = SOCK_SEQPACKET,
1087 };
1088
1089 static int __init pep_register(void)
1090 {
1091 return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1092 }
1093
1094 static void __exit pep_unregister(void)
1095 {
1096 phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1097 }
1098
1099 module_init(pep_register);
1100 module_exit(pep_unregister);
1101 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1102 MODULE_DESCRIPTION("Phonet pipe protocol");
1103 MODULE_LICENSE("GPL");
1104 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);
linux-next