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ARM: 7409/1: Do not call flush_cache_user_range with mmap_sem held
[linux/fpc-iii.git] / net / phonet / pep.c
blobd29a7fb3f61db0302f8789f14b9d645fd8aaa10e
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, 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 #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */
54
55 /* Get the next TLV sub-block. */
56 static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen,
57 void *buf)
58 {
59 void *data = NULL;
60 struct {
61 u8 sb_type;
62 u8 sb_len;
63 } *ph, h;
64 int buflen = *plen;
65
66 ph = skb_header_pointer(skb, 0, 2, &h);
67 if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len))
68 return NULL;
69 ph->sb_len -= 2;
70 *ptype = ph->sb_type;
71 *plen = ph->sb_len;
72
73 if (buflen > ph->sb_len)
74 buflen = ph->sb_len;
75 data = skb_header_pointer(skb, 2, buflen, buf);
76 __skb_pull(skb, 2 + ph->sb_len);
77 return data;
78 }
79
80 static struct sk_buff *pep_alloc_skb(struct sock *sk, const void *payload,
81 int len, gfp_t priority)
82 {
83 struct sk_buff *skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority);
84 if (!skb)
85 return NULL;
86 skb_set_owner_w(skb, sk);
87
88 skb_reserve(skb, MAX_PNPIPE_HEADER);
89 __skb_put(skb, len);
90 skb_copy_to_linear_data(skb, payload, len);
91 __skb_push(skb, sizeof(struct pnpipehdr));
92 skb_reset_transport_header(skb);
93 return skb;
94 }
95
96 static int pep_reply(struct sock *sk, struct sk_buff *oskb, u8 code,
97 const void *data, int len, gfp_t priority)
98 {
99 const struct pnpipehdr *oph = pnp_hdr(oskb);
100 struct pnpipehdr *ph;
101 struct sk_buff *skb;
102 struct sockaddr_pn peer;
103
104 skb = pep_alloc_skb(sk, data, len, priority);
105 if (!skb)
106 return -ENOMEM;
107
108 ph = pnp_hdr(skb);
109 ph->utid = oph->utid;
110 ph->message_id = oph->message_id + 1; /* REQ -> RESP */
111 ph->pipe_handle = oph->pipe_handle;
112 ph->error_code = code;
113
114 pn_skb_get_src_sockaddr(oskb, &peer);
115 return pn_skb_send(sk, skb, &peer);
116 }
117
118 static int pep_indicate(struct sock *sk, u8 id, u8 code,
119 const void *data, int len, gfp_t priority)
120 {
121 struct pep_sock *pn = pep_sk(sk);
122 struct pnpipehdr *ph;
123 struct sk_buff *skb;
124
125 skb = pep_alloc_skb(sk, data, len, priority);
126 if (!skb)
127 return -ENOMEM;
128
129 ph = pnp_hdr(skb);
130 ph->utid = 0;
131 ph->message_id = id;
132 ph->pipe_handle = pn->pipe_handle;
133 ph->data[0] = code;
134 return pn_skb_send(sk, skb, NULL);
135 }
136
137 #define PAD 0x00
138
139 static int pipe_handler_request(struct sock *sk, u8 id, u8 code,
140 const void *data, int len)
141 {
142 struct pep_sock *pn = pep_sk(sk);
143 struct pnpipehdr *ph;
144 struct sk_buff *skb;
145
146 skb = pep_alloc_skb(sk, data, len, GFP_KERNEL);
147 if (!skb)
148 return -ENOMEM;
149
150 ph = pnp_hdr(skb);
151 ph->utid = id; /* whatever */
152 ph->message_id = id;
153 ph->pipe_handle = pn->pipe_handle;
154 ph->data[0] = code;
155 return pn_skb_send(sk, skb, NULL);
156 }
157
158 static int pipe_handler_send_created_ind(struct sock *sk)
159 {
160 struct pep_sock *pn = pep_sk(sk);
161 u8 data[4] = {
162 PN_PIPE_SB_NEGOTIATED_FC, pep_sb_size(2),
163 pn->tx_fc, pn->rx_fc,
164 };
165
166 return pep_indicate(sk, PNS_PIPE_CREATED_IND, 1 /* sub-blocks */,
167 data, 4, GFP_ATOMIC);
168 }
169
170 static int pep_accept_conn(struct sock *sk, struct sk_buff *skb)
171 {
172 static const u8 data[20] = {
173 PAD, PAD, PAD, 2 /* sub-blocks */,
174 PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD,
175 PN_MULTI_CREDIT_FLOW_CONTROL,
176 PN_ONE_CREDIT_FLOW_CONTROL,
177 PN_LEGACY_FLOW_CONTROL,
178 PAD,
179 PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD,
180 PN_MULTI_CREDIT_FLOW_CONTROL,
181 PN_ONE_CREDIT_FLOW_CONTROL,
182 PN_LEGACY_FLOW_CONTROL,
183 PAD,
184 };
185
186 might_sleep();
187 return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data),
188 GFP_KERNEL);
189 }
190
191 static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code,
192 gfp_t priority)
193 {
194 static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ };
195 WARN_ON(code == PN_PIPE_NO_ERROR);
196 return pep_reply(sk, skb, code, data, sizeof(data), priority);
197 }
198
199 /* Control requests are not sent by the pipe service and have a specific
200 * message format. */
201 static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
202 gfp_t priority)
203 {
204 const struct pnpipehdr *oph = pnp_hdr(oskb);
205 struct sk_buff *skb;
206 struct pnpipehdr *ph;
207 struct sockaddr_pn dst;
208 u8 data[4] = {
209 oph->data[0], /* PEP type */
210 code, /* error code, at an unusual offset */
211 PAD, PAD,
212 };
213
214 skb = pep_alloc_skb(sk, data, 4, priority);
215 if (!skb)
216 return -ENOMEM;
217
218 ph = pnp_hdr(skb);
219 ph->utid = oph->utid;
220 ph->message_id = PNS_PEP_CTRL_RESP;
221 ph->pipe_handle = oph->pipe_handle;
222 ph->data[0] = oph->data[1]; /* CTRL id */
223
224 pn_skb_get_src_sockaddr(oskb, &dst);
225 return pn_skb_send(sk, skb, &dst);
226 }
227
228 static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority)
229 {
230 u8 data[4] = { type, PAD, PAD, status };
231
232 return pep_indicate(sk, PNS_PEP_STATUS_IND, PN_PEP_TYPE_COMMON,
233 data, 4, priority);
234 }
235
236 /* Send our RX flow control information to the sender.
237 * Socket must be locked. */
238 static void pipe_grant_credits(struct sock *sk, gfp_t priority)
239 {
240 struct pep_sock *pn = pep_sk(sk);
241
242 BUG_ON(sk->sk_state != TCP_ESTABLISHED);
243
244 switch (pn->rx_fc) {
245 case PN_LEGACY_FLOW_CONTROL: /* TODO */
246 break;
247 case PN_ONE_CREDIT_FLOW_CONTROL:
248 if (pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL,
249 PEP_IND_READY, priority) == 0)
250 pn->rx_credits = 1;
251 break;
252 case PN_MULTI_CREDIT_FLOW_CONTROL:
253 if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX)
254 break;
255 if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
256 CREDITS_MAX - pn->rx_credits,
257 priority) == 0)
258 pn->rx_credits = CREDITS_MAX;
259 break;
260 }
261 }
262
263 static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb)
264 {
265 struct pep_sock *pn = pep_sk(sk);
266 struct pnpipehdr *hdr;
267 int wake = 0;
268
269 if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
270 return -EINVAL;
271
272 hdr = pnp_hdr(skb);
273 if (hdr->data[0] != PN_PEP_TYPE_COMMON) {
274 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n",
275 (unsigned)hdr->data[0]);
276 return -EOPNOTSUPP;
277 }
278
279 switch (hdr->data[1]) {
280 case PN_PEP_IND_FLOW_CONTROL:
281 switch (pn->tx_fc) {
282 case PN_LEGACY_FLOW_CONTROL:
283 switch (hdr->data[4]) {
284 case PEP_IND_BUSY:
285 atomic_set(&pn->tx_credits, 0);
286 break;
287 case PEP_IND_READY:
288 atomic_set(&pn->tx_credits, wake = 1);
289 break;
290 }
291 break;
292 case PN_ONE_CREDIT_FLOW_CONTROL:
293 if (hdr->data[4] == PEP_IND_READY)
294 atomic_set(&pn->tx_credits, wake = 1);
295 break;
296 }
297 break;
298
299 case PN_PEP_IND_ID_MCFC_GRANT_CREDITS:
300 if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL)
301 break;
302 atomic_add(wake = hdr->data[4], &pn->tx_credits);
303 break;
304
305 default:
306 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n",
307 (unsigned)hdr->data[1]);
308 return -EOPNOTSUPP;
309 }
310 if (wake)
311 sk->sk_write_space(sk);
312 return 0;
313 }
314
315 static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb)
316 {
317 struct pep_sock *pn = pep_sk(sk);
318 struct pnpipehdr *hdr = pnp_hdr(skb);
319 u8 n_sb = hdr->data[0];
320
321 pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
322 __skb_pull(skb, sizeof(*hdr));
323 while (n_sb > 0) {
324 u8 type, buf[2], len = sizeof(buf);
325 u8 *data = pep_get_sb(skb, &type, &len, buf);
326
327 if (data == NULL)
328 return -EINVAL;
329 switch (type) {
330 case PN_PIPE_SB_NEGOTIATED_FC:
331 if (len < 2 || (data[0] | data[1]) > 3)
332 break;
333 pn->tx_fc = data[0] & 3;
334 pn->rx_fc = data[1] & 3;
335 break;
336 }
337 n_sb--;
338 }
339 return 0;
340 }
341
342 /* Queue an skb to a connected sock.
343 * Socket lock must be held. */
344 static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
345 {
346 struct pep_sock *pn = pep_sk(sk);
347 struct pnpipehdr *hdr = pnp_hdr(skb);
348 struct sk_buff_head *queue;
349 int err = 0;
350
351 BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
352
353 switch (hdr->message_id) {
354 case PNS_PEP_CONNECT_REQ:
355 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_ATOMIC);
356 break;
357
358 case PNS_PEP_DISCONNECT_REQ:
359 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
360 sk->sk_state = TCP_CLOSE_WAIT;
361 if (!sock_flag(sk, SOCK_DEAD))
362 sk->sk_state_change(sk);
363 break;
364
365 case PNS_PEP_ENABLE_REQ:
366 /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */
367 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
368 break;
369
370 case PNS_PEP_RESET_REQ:
371 switch (hdr->state_after_reset) {
372 case PN_PIPE_DISABLE:
373 pn->init_enable = 0;
374 break;
375 case PN_PIPE_ENABLE:
376 pn->init_enable = 1;
377 break;
378 default: /* not allowed to send an error here!? */
379 err = -EINVAL;
380 goto out;
381 }
382 /* fall through */
383 case PNS_PEP_DISABLE_REQ:
384 atomic_set(&pn->tx_credits, 0);
385 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
386 break;
387
388 case PNS_PEP_CTRL_REQ:
389 if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) {
390 atomic_inc(&sk->sk_drops);
391 break;
392 }
393 __skb_pull(skb, 4);
394 queue = &pn->ctrlreq_queue;
395 goto queue;
396
397 case PNS_PIPE_ALIGNED_DATA:
398 __skb_pull(skb, 1);
399 /* fall through */
400 case PNS_PIPE_DATA:
401 __skb_pull(skb, 3); /* Pipe data header */
402 if (!pn_flow_safe(pn->rx_fc)) {
403 err = sock_queue_rcv_skb(sk, skb);
404 if (!err)
405 return NET_RX_SUCCESS;
406 err = -ENOBUFS;
407 break;
408 }
409
410 if (pn->rx_credits == 0) {
411 atomic_inc(&sk->sk_drops);
412 err = -ENOBUFS;
413 break;
414 }
415 pn->rx_credits--;
416 queue = &sk->sk_receive_queue;
417 goto queue;
418
419 case PNS_PEP_STATUS_IND:
420 pipe_rcv_status(sk, skb);
421 break;
422
423 case PNS_PIPE_REDIRECTED_IND:
424 err = pipe_rcv_created(sk, skb);
425 break;
426
427 case PNS_PIPE_CREATED_IND:
428 err = pipe_rcv_created(sk, skb);
429 if (err)
430 break;
431 /* fall through */
432 case PNS_PIPE_RESET_IND:
433 if (!pn->init_enable)
434 break;
435 /* fall through */
436 case PNS_PIPE_ENABLED_IND:
437 if (!pn_flow_safe(pn->tx_fc)) {
438 atomic_set(&pn->tx_credits, 1);
439 sk->sk_write_space(sk);
440 }
441 if (sk->sk_state == TCP_ESTABLISHED)
442 break; /* Nothing to do */
443 sk->sk_state = TCP_ESTABLISHED;
444 pipe_grant_credits(sk, GFP_ATOMIC);
445 break;
446
447 case PNS_PIPE_DISABLED_IND:
448 sk->sk_state = TCP_SYN_RECV;
449 pn->rx_credits = 0;
450 break;
451
452 default:
453 LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n",
454 hdr->message_id);
455 err = -EINVAL;
456 }
457 out:
458 kfree_skb(skb);
459 return (err == -ENOBUFS) ? NET_RX_DROP : NET_RX_SUCCESS;
460
461 queue:
462 skb->dev = NULL;
463 skb_set_owner_r(skb, sk);
464 err = skb->len;
465 skb_queue_tail(queue, skb);
466 if (!sock_flag(sk, SOCK_DEAD))
467 sk->sk_data_ready(sk, err);
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 n)
481 {
482 unsigned 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 /* Queue an skb to an actively connected sock.
537 * Socket lock must be held. */
538 static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb)
539 {
540 struct pep_sock *pn = pep_sk(sk);
541 struct pnpipehdr *hdr = pnp_hdr(skb);
542 int err = NET_RX_SUCCESS;
543
544 switch (hdr->message_id) {
545 case PNS_PIPE_ALIGNED_DATA:
546 __skb_pull(skb, 1);
547 /* fall through */
548 case PNS_PIPE_DATA:
549 __skb_pull(skb, 3); /* Pipe data header */
550 if (!pn_flow_safe(pn->rx_fc)) {
551 err = sock_queue_rcv_skb(sk, skb);
552 if (!err)
553 return NET_RX_SUCCESS;
554 err = NET_RX_DROP;
555 break;
556 }
557
558 if (pn->rx_credits == 0) {
559 atomic_inc(&sk->sk_drops);
560 err = NET_RX_DROP;
561 break;
562 }
563 pn->rx_credits--;
564 skb->dev = NULL;
565 skb_set_owner_r(skb, sk);
566 err = skb->len;
567 skb_queue_tail(&sk->sk_receive_queue, skb);
568 if (!sock_flag(sk, SOCK_DEAD))
569 sk->sk_data_ready(sk, err);
570 return NET_RX_SUCCESS;
571
572 case PNS_PEP_CONNECT_RESP:
573 if (sk->sk_state != TCP_SYN_SENT)
574 break;
575 if (!sock_flag(sk, SOCK_DEAD))
576 sk->sk_state_change(sk);
577 if (pep_connresp_rcv(sk, skb)) {
578 sk->sk_state = TCP_CLOSE_WAIT;
579 break;
580 }
581
582 sk->sk_state = TCP_ESTABLISHED;
583 if (!pn_flow_safe(pn->tx_fc)) {
584 atomic_set(&pn->tx_credits, 1);
585 sk->sk_write_space(sk);
586 }
587 pipe_grant_credits(sk, GFP_ATOMIC);
588 break;
589
590 case PNS_PEP_DISCONNECT_RESP:
591 /* sock should already be dead, nothing to do */
592 break;
593
594 case PNS_PEP_STATUS_IND:
595 pipe_rcv_status(sk, skb);
596 break;
597 }
598 kfree_skb(skb);
599 return err;
600 }
601
602 /* Listening sock must be locked */
603 static struct sock *pep_find_pipe(const struct hlist_head *hlist,
604 const struct sockaddr_pn *dst,
605 u8 pipe_handle)
606 {
607 struct hlist_node *node;
608 struct sock *sknode;
609 u16 dobj = pn_sockaddr_get_object(dst);
610
611 sk_for_each(sknode, node, hlist) {
612 struct pep_sock *pnnode = pep_sk(sknode);
613
614 /* Ports match, but addresses might not: */
615 if (pnnode->pn_sk.sobject != dobj)
616 continue;
617 if (pnnode->pipe_handle != pipe_handle)
618 continue;
619 if (sknode->sk_state == TCP_CLOSE_WAIT)
620 continue;
621
622 sock_hold(sknode);
623 return sknode;
624 }
625 return NULL;
626 }
627
628 /*
629 * Deliver an skb to a listening sock.
630 * Socket lock must be held.
631 * We then queue the skb to the right connected sock (if any).
632 */
633 static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
634 {
635 struct pep_sock *pn = pep_sk(sk);
636 struct sock *sknode;
637 struct pnpipehdr *hdr;
638 struct sockaddr_pn dst;
639 u8 pipe_handle;
640
641 if (!pskb_may_pull(skb, sizeof(*hdr)))
642 goto drop;
643
644 hdr = pnp_hdr(skb);
645 pipe_handle = hdr->pipe_handle;
646 if (pipe_handle == PN_PIPE_INVALID_HANDLE)
647 goto drop;
648
649 pn_skb_get_dst_sockaddr(skb, &dst);
650
651 /* Look for an existing pipe handle */
652 sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
653 if (sknode)
654 return sk_receive_skb(sknode, skb, 1);
655
656 switch (hdr->message_id) {
657 case PNS_PEP_CONNECT_REQ:
658 if (sk->sk_state != TCP_LISTEN || sk_acceptq_is_full(sk)) {
659 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE,
660 GFP_ATOMIC);
661 break;
662 }
663 skb_queue_head(&sk->sk_receive_queue, skb);
664 sk_acceptq_added(sk);
665 if (!sock_flag(sk, SOCK_DEAD))
666 sk->sk_data_ready(sk, 0);
667 return NET_RX_SUCCESS;
668
669 case PNS_PEP_DISCONNECT_REQ:
670 pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC);
671 break;
672
673 case PNS_PEP_CTRL_REQ:
674 pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
675 break;
676
677 case PNS_PEP_RESET_REQ:
678 case PNS_PEP_ENABLE_REQ:
679 case PNS_PEP_DISABLE_REQ:
680 /* invalid handle is not even allowed here! */
681 break;
682
683 default:
684 if ((1 << sk->sk_state)
685 & ~(TCPF_CLOSE|TCPF_LISTEN|TCPF_CLOSE_WAIT))
686 /* actively connected socket */
687 return pipe_handler_do_rcv(sk, skb);
688 }
689 drop:
690 kfree_skb(skb);
691 return NET_RX_SUCCESS;
692 }
693
694 static int pipe_do_remove(struct sock *sk)
695 {
696 struct pep_sock *pn = pep_sk(sk);
697 struct pnpipehdr *ph;
698 struct sk_buff *skb;
699
700 skb = pep_alloc_skb(sk, NULL, 0, GFP_KERNEL);
701 if (!skb)
702 return -ENOMEM;
703
704 ph = pnp_hdr(skb);
705 ph->utid = 0;
706 ph->message_id = PNS_PIPE_REMOVE_REQ;
707 ph->pipe_handle = pn->pipe_handle;
708 ph->data[0] = PAD;
709 return pn_skb_send(sk, skb, NULL);
710 }
711
712 /* associated socket ceases to exist */
713 static void pep_sock_close(struct sock *sk, long timeout)
714 {
715 struct pep_sock *pn = pep_sk(sk);
716 int ifindex = 0;
717
718 sock_hold(sk); /* keep a reference after sk_common_release() */
719 sk_common_release(sk);
720
721 lock_sock(sk);
722 if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) {
723 if (sk->sk_backlog_rcv == pipe_do_rcv)
724 /* Forcefully remove dangling Phonet pipe */
725 pipe_do_remove(sk);
726 else
727 pipe_handler_request(sk, PNS_PEP_DISCONNECT_REQ, PAD,
728 NULL, 0);
729 }
730 sk->sk_state = TCP_CLOSE;
731
732 ifindex = pn->ifindex;
733 pn->ifindex = 0;
734 release_sock(sk);
735
736 if (ifindex)
737 gprs_detach(sk);
738 sock_put(sk);
739 }
740
741 static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp)
742 {
743 struct pep_sock *pn = pep_sk(sk), *newpn;
744 struct sock *newsk = NULL;
745 struct sk_buff *skb;
746 struct pnpipehdr *hdr;
747 struct sockaddr_pn dst, src;
748 int err;
749 u16 peer_type;
750 u8 pipe_handle, enabled, n_sb;
751 u8 aligned = 0;
752
753 skb = skb_recv_datagram(sk, 0, flags & O_NONBLOCK, errp);
754 if (!skb)
755 return NULL;
756
757 lock_sock(sk);
758 if (sk->sk_state != TCP_LISTEN) {
759 err = -EINVAL;
760 goto drop;
761 }
762 sk_acceptq_removed(sk);
763
764 err = -EPROTO;
765 if (!pskb_may_pull(skb, sizeof(*hdr) + 4))
766 goto drop;
767
768 hdr = pnp_hdr(skb);
769 pipe_handle = hdr->pipe_handle;
770 switch (hdr->state_after_connect) {
771 case PN_PIPE_DISABLE:
772 enabled = 0;
773 break;
774 case PN_PIPE_ENABLE:
775 enabled = 1;
776 break;
777 default:
778 pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM,
779 GFP_KERNEL);
780 goto drop;
781 }
782 peer_type = hdr->other_pep_type << 8;
783
784 /* Parse sub-blocks (options) */
785 n_sb = hdr->data[4];
786 while (n_sb > 0) {
787 u8 type, buf[1], len = sizeof(buf);
788 const u8 *data = pep_get_sb(skb, &type, &len, buf);
789
790 if (data == NULL)
791 goto drop;
792 switch (type) {
793 case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE:
794 if (len < 1)
795 goto drop;
796 peer_type = (peer_type & 0xff00) | data[0];
797 break;
798 case PN_PIPE_SB_ALIGNED_DATA:
799 aligned = data[0] != 0;
800 break;
801 }
802 n_sb--;
803 }
804
805 /* Check for duplicate pipe handle */
806 newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle);
807 if (unlikely(newsk)) {
808 __sock_put(newsk);
809 newsk = NULL;
810 pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_KERNEL);
811 goto drop;
812 }
813
814 /* Create a new to-be-accepted sock */
815 newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_KERNEL, sk->sk_prot);
816 if (!newsk) {
817 pep_reject_conn(sk, skb, PN_PIPE_ERR_OVERLOAD, GFP_KERNEL);
818 err = -ENOBUFS;
819 goto drop;
820 }
821
822 sock_init_data(NULL, newsk);
823 newsk->sk_state = TCP_SYN_RECV;
824 newsk->sk_backlog_rcv = pipe_do_rcv;
825 newsk->sk_protocol = sk->sk_protocol;
826 newsk->sk_destruct = pipe_destruct;
827
828 newpn = pep_sk(newsk);
829 pn_skb_get_dst_sockaddr(skb, &dst);
830 pn_skb_get_src_sockaddr(skb, &src);
831 newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
832 newpn->pn_sk.dobject = pn_sockaddr_get_object(&src);
833 newpn->pn_sk.resource = pn_sockaddr_get_resource(&dst);
834 sock_hold(sk);
835 newpn->listener = sk;
836 skb_queue_head_init(&newpn->ctrlreq_queue);
837 newpn->pipe_handle = pipe_handle;
838 atomic_set(&newpn->tx_credits, 0);
839 newpn->ifindex = 0;
840 newpn->peer_type = peer_type;
841 newpn->rx_credits = 0;
842 newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL;
843 newpn->init_enable = enabled;
844 newpn->aligned = aligned;
845
846 err = pep_accept_conn(newsk, skb);
847 if (err) {
848 sock_put(newsk);
849 newsk = NULL;
850 goto drop;
851 }
852 sk_add_node(newsk, &pn->hlist);
853 drop:
854 release_sock(sk);
855 kfree_skb(skb);
856 *errp = err;
857 return newsk;
858 }
859
860 static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len)
861 {
862 struct pep_sock *pn = pep_sk(sk);
863 int err;
864 u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD };
865
866 pn->pipe_handle = 1; /* anything but INVALID_HANDLE */
867 err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ,
868 PN_PIPE_ENABLE, data, 4);
869 if (err) {
870 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
871 return err;
872 }
873 sk->sk_state = TCP_SYN_SENT;
874 return 0;
875 }
876
877 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
878 {
879 struct pep_sock *pn = pep_sk(sk);
880 int answ;
881
882 switch (cmd) {
883 case SIOCINQ:
884 if (sk->sk_state == TCP_LISTEN)
885 return -EINVAL;
886
887 lock_sock(sk);
888 if (sock_flag(sk, SOCK_URGINLINE) &&
889 !skb_queue_empty(&pn->ctrlreq_queue))
890 answ = skb_peek(&pn->ctrlreq_queue)->len;
891 else if (!skb_queue_empty(&sk->sk_receive_queue))
892 answ = skb_peek(&sk->sk_receive_queue)->len;
893 else
894 answ = 0;
895 release_sock(sk);
896 return put_user(answ, (int __user *)arg);
897 }
898
899 return -ENOIOCTLCMD;
900 }
901
902 static int pep_init(struct sock *sk)
903 {
904 struct pep_sock *pn = pep_sk(sk);
905
906 sk->sk_destruct = pipe_destruct;
907 INIT_HLIST_HEAD(&pn->hlist);
908 pn->listener = NULL;
909 skb_queue_head_init(&pn->ctrlreq_queue);
910 atomic_set(&pn->tx_credits, 0);
911 pn->ifindex = 0;
912 pn->peer_type = 0;
913 pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
914 pn->rx_credits = 0;
915 pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL;
916 pn->init_enable = 1;
917 pn->aligned = 0;
918 return 0;
919 }
920
921 static int pep_setsockopt(struct sock *sk, int level, int optname,
922 char __user *optval, unsigned int optlen)
923 {
924 struct pep_sock *pn = pep_sk(sk);
925 int val = 0, err = 0;
926
927 if (level != SOL_PNPIPE)
928 return -ENOPROTOOPT;
929 if (optlen >= sizeof(int)) {
930 if (get_user(val, (int __user *) optval))
931 return -EFAULT;
932 }
933
934 lock_sock(sk);
935 switch (optname) {
936 case PNPIPE_ENCAP:
937 if (val && val != PNPIPE_ENCAP_IP) {
938 err = -EINVAL;
939 break;
940 }
941 if (!pn->ifindex == !val)
942 break; /* Nothing to do! */
943 if (!capable(CAP_NET_ADMIN)) {
944 err = -EPERM;
945 break;
946 }
947 if (val) {
948 release_sock(sk);
949 err = gprs_attach(sk);
950 if (err > 0) {
951 pn->ifindex = err;
952 err = 0;
953 }
954 } else {
955 pn->ifindex = 0;
956 release_sock(sk);
957 gprs_detach(sk);
958 err = 0;
959 }
960 goto out_norel;
961
962 default:
963 err = -ENOPROTOOPT;
964 }
965 release_sock(sk);
966
967 out_norel:
968 return err;
969 }
970
971 static int pep_getsockopt(struct sock *sk, int level, int optname,
972 char __user *optval, int __user *optlen)
973 {
974 struct pep_sock *pn = pep_sk(sk);
975 int len, val;
976
977 if (level != SOL_PNPIPE)
978 return -ENOPROTOOPT;
979 if (get_user(len, optlen))
980 return -EFAULT;
981
982 switch (optname) {
983 case PNPIPE_ENCAP:
984 val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE;
985 break;
986
987 case PNPIPE_IFINDEX:
988 val = pn->ifindex;
989 break;
990
991 case PNPIPE_HANDLE:
992 val = pn->pipe_handle;
993 if (val == PN_PIPE_INVALID_HANDLE)
994 return -EINVAL;
995 break;
996
997 default:
998 return -ENOPROTOOPT;
999 }
1000
1001 len = min_t(unsigned int, sizeof(int), len);
1002 if (put_user(len, optlen))
1003 return -EFAULT;
1004 if (put_user(val, (int __user *) optval))
1005 return -EFAULT;
1006 return 0;
1007 }
1008
1009 static int pipe_skb_send(struct sock *sk, struct sk_buff *skb)
1010 {
1011 struct pep_sock *pn = pep_sk(sk);
1012 struct pnpipehdr *ph;
1013 int err;
1014
1015 if (pn_flow_safe(pn->tx_fc) &&
1016 !atomic_add_unless(&pn->tx_credits, -1, 0)) {
1017 kfree_skb(skb);
1018 return -ENOBUFS;
1019 }
1020
1021 skb_push(skb, 3 + pn->aligned);
1022 skb_reset_transport_header(skb);
1023 ph = pnp_hdr(skb);
1024 ph->utid = 0;
1025 if (pn->aligned) {
1026 ph->message_id = PNS_PIPE_ALIGNED_DATA;
1027 ph->data[0] = 0; /* padding */
1028 } else
1029 ph->message_id = PNS_PIPE_DATA;
1030 ph->pipe_handle = pn->pipe_handle;
1031 err = pn_skb_send(sk, skb, NULL);
1032
1033 if (err && pn_flow_safe(pn->tx_fc))
1034 atomic_inc(&pn->tx_credits);
1035 return err;
1036
1037 }
1038
1039 static int pep_sendmsg(struct kiocb *iocb, struct sock *sk,
1040 struct msghdr *msg, size_t len)
1041 {
1042 struct pep_sock *pn = pep_sk(sk);
1043 struct sk_buff *skb;
1044 long timeo;
1045 int flags = msg->msg_flags;
1046 int err, done;
1047
1048 if (len > USHRT_MAX)
1049 return -EMSGSIZE;
1050
1051 if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
1052 MSG_CMSG_COMPAT)) ||
1053 !(msg->msg_flags & MSG_EOR))
1054 return -EOPNOTSUPP;
1055
1056 skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
1057 flags & MSG_DONTWAIT, &err);
1058 if (!skb)
1059 return err;
1060
1061 skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned);
1062 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1063 if (err < 0)
1064 goto outfree;
1065
1066 lock_sock(sk);
1067 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1068 if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
1069 err = -ENOTCONN;
1070 goto out;
1071 }
1072 if (sk->sk_state != TCP_ESTABLISHED) {
1073 /* Wait until the pipe gets to enabled state */
1074 disabled:
1075 err = sk_stream_wait_connect(sk, &timeo);
1076 if (err)
1077 goto out;
1078
1079 if (sk->sk_state == TCP_CLOSE_WAIT) {
1080 err = -ECONNRESET;
1081 goto out;
1082 }
1083 }
1084 BUG_ON(sk->sk_state != TCP_ESTABLISHED);
1085
1086 /* Wait until flow control allows TX */
1087 done = atomic_read(&pn->tx_credits);
1088 while (!done) {
1089 DEFINE_WAIT(wait);
1090
1091 if (!timeo) {
1092 err = -EAGAIN;
1093 goto out;
1094 }
1095 if (signal_pending(current)) {
1096 err = sock_intr_errno(timeo);
1097 goto out;
1098 }
1099
1100 prepare_to_wait(sk_sleep(sk), &wait,
1101 TASK_INTERRUPTIBLE);
1102 done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits));
1103 finish_wait(sk_sleep(sk), &wait);
1104
1105 if (sk->sk_state != TCP_ESTABLISHED)
1106 goto disabled;
1107 }
1108
1109 err = pipe_skb_send(sk, skb);
1110 if (err >= 0)
1111 err = len; /* success! */
1112 skb = NULL;
1113 out:
1114 release_sock(sk);
1115 outfree:
1116 kfree_skb(skb);
1117 return err;
1118 }
1119
1120 int pep_writeable(struct sock *sk)
1121 {
1122 struct pep_sock *pn = pep_sk(sk);
1123
1124 return atomic_read(&pn->tx_credits);
1125 }
1126
1127 int pep_write(struct sock *sk, struct sk_buff *skb)
1128 {
1129 struct sk_buff *rskb, *fs;
1130 int flen = 0;
1131
1132 if (pep_sk(sk)->aligned)
1133 return pipe_skb_send(sk, skb);
1134
1135 rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC);
1136 if (!rskb) {
1137 kfree_skb(skb);
1138 return -ENOMEM;
1139 }
1140 skb_shinfo(rskb)->frag_list = skb;
1141 rskb->len += skb->len;
1142 rskb->data_len += rskb->len;
1143 rskb->truesize += rskb->len;
1144
1145 /* Avoid nested fragments */
1146 skb_walk_frags(skb, fs)
1147 flen += fs->len;
1148 skb->next = skb_shinfo(skb)->frag_list;
1149 skb_frag_list_init(skb);
1150 skb->len -= flen;
1151 skb->data_len -= flen;
1152 skb->truesize -= flen;
1153
1154 skb_reserve(rskb, MAX_PHONET_HEADER + 3);
1155 return pipe_skb_send(sk, rskb);
1156 }
1157
1158 struct sk_buff *pep_read(struct sock *sk)
1159 {
1160 struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue);
1161
1162 if (sk->sk_state == TCP_ESTABLISHED)
1163 pipe_grant_credits(sk, GFP_ATOMIC);
1164 return skb;
1165 }
1166
1167 static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
1168 struct msghdr *msg, size_t len, int noblock,
1169 int flags, int *addr_len)
1170 {
1171 struct sk_buff *skb;
1172 int err;
1173
1174 if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
1175 MSG_NOSIGNAL|MSG_CMSG_COMPAT))
1176 return -EOPNOTSUPP;
1177
1178 if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
1179 return -ENOTCONN;
1180
1181 if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
1182 /* Dequeue and acknowledge control request */
1183 struct pep_sock *pn = pep_sk(sk);
1184
1185 if (flags & MSG_PEEK)
1186 return -EOPNOTSUPP;
1187 skb = skb_dequeue(&pn->ctrlreq_queue);
1188 if (skb) {
1189 pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
1190 GFP_KERNEL);
1191 msg->msg_flags |= MSG_OOB;
1192 goto copy;
1193 }
1194 if (flags & MSG_OOB)
1195 return -EINVAL;
1196 }
1197
1198 skb = skb_recv_datagram(sk, flags, noblock, &err);
1199 lock_sock(sk);
1200 if (skb == NULL) {
1201 if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
1202 err = -ECONNRESET;
1203 release_sock(sk);
1204 return err;
1205 }
1206
1207 if (sk->sk_state == TCP_ESTABLISHED)
1208 pipe_grant_credits(sk, GFP_KERNEL);
1209 release_sock(sk);
1210 copy:
1211 msg->msg_flags |= MSG_EOR;
1212 if (skb->len > len)
1213 msg->msg_flags |= MSG_TRUNC;
1214 else
1215 len = skb->len;
1216
1217 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
1218 if (!err)
1219 err = (flags & MSG_TRUNC) ? skb->len : len;
1220
1221 skb_free_datagram(sk, skb);
1222 return err;
1223 }
1224
1225 static void pep_sock_unhash(struct sock *sk)
1226 {
1227 struct pep_sock *pn = pep_sk(sk);
1228 struct sock *skparent = NULL;
1229
1230 lock_sock(sk);
1231
1232 if (pn->listener != NULL) {
1233 skparent = pn->listener;
1234 pn->listener = NULL;
1235 release_sock(sk);
1236
1237 pn = pep_sk(skparent);
1238 lock_sock(skparent);
1239 sk_del_node_init(sk);
1240 sk = skparent;
1241 }
1242
1243 /* Unhash a listening sock only when it is closed
1244 * and all of its active connected pipes are closed. */
1245 if (hlist_empty(&pn->hlist))
1246 pn_sock_unhash(&pn->pn_sk.sk);
1247 release_sock(sk);
1248
1249 if (skparent)
1250 sock_put(skparent);
1251 }
1252
1253 static struct proto pep_proto = {
1254 .close = pep_sock_close,
1255 .accept = pep_sock_accept,
1256 .connect = pep_sock_connect,
1257 .ioctl = pep_ioctl,
1258 .init = pep_init,
1259 .setsockopt = pep_setsockopt,
1260 .getsockopt = pep_getsockopt,
1261 .sendmsg = pep_sendmsg,
1262 .recvmsg = pep_recvmsg,
1263 .backlog_rcv = pep_do_rcv,
1264 .hash = pn_sock_hash,
1265 .unhash = pep_sock_unhash,
1266 .get_port = pn_sock_get_port,
1267 .obj_size = sizeof(struct pep_sock),
1268 .owner = THIS_MODULE,
1269 .name = "PNPIPE",
1270 };
1271
1272 static struct phonet_protocol pep_pn_proto = {
1273 .ops = &phonet_stream_ops,
1274 .prot = &pep_proto,
1275 .sock_type = SOCK_SEQPACKET,
1276 };
1277
1278 static int __init pep_register(void)
1279 {
1280 return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto);
1281 }
1282
1283 static void __exit pep_unregister(void)
1284 {
1285 phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto);
1286 }
1287
1288 module_init(pep_register);
1289 module_exit(pep_unregister);
1290 MODULE_AUTHOR("Remi Denis-Courmont, Nokia");
1291 MODULE_DESCRIPTION("Phonet pipe protocol");
1292 MODULE_LICENSE("GPL");
1293 MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE);
Linux with added FPC-III support