Commit | Line | Data |
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9641458d RDC |
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/socket.h> | |
27 | #include <net/sock.h> | |
28 | #include <net/tcp_states.h> | |
29 | #include <asm/ioctls.h> | |
30 | ||
31 | #include <linux/phonet.h> | |
32 | #include <net/phonet/phonet.h> | |
33 | #include <net/phonet/pep.h> | |
34 | ||
35 | /* sk_state values: | |
36 | * TCP_CLOSE sock not in use yet | |
37 | * TCP_CLOSE_WAIT disconnected pipe | |
38 | * TCP_LISTEN listening pipe endpoint | |
39 | * TCP_SYN_RECV connected pipe in disabled state | |
40 | * TCP_ESTABLISHED connected pipe in enabled state | |
41 | * | |
42 | * pep_sock locking: | |
43 | * - sk_state, ackq, hlist: sock lock needed | |
44 | * - listener: read only | |
45 | * - pipe_handle: read only | |
46 | */ | |
47 | ||
48 | #define CREDITS_MAX 10 | |
49 | #define CREDITS_THR 7 | |
50 | ||
51 | static const struct sockaddr_pn pipe_srv = { | |
52 | .spn_family = AF_PHONET, | |
53 | .spn_resource = 0xD9, /* pipe service */ | |
54 | }; | |
55 | ||
56 | #define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */ | |
57 | ||
58 | /* Get the next TLV sub-block. */ | |
59 | static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen, | |
60 | void *buf) | |
61 | { | |
62 | void *data = NULL; | |
63 | struct { | |
64 | u8 sb_type; | |
65 | u8 sb_len; | |
66 | } *ph, h; | |
67 | int buflen = *plen; | |
68 | ||
69 | ph = skb_header_pointer(skb, 0, 2, &h); | |
70 | if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len)) | |
71 | return NULL; | |
72 | ph->sb_len -= 2; | |
73 | *ptype = ph->sb_type; | |
74 | *plen = ph->sb_len; | |
75 | ||
76 | if (buflen > ph->sb_len) | |
77 | buflen = ph->sb_len; | |
78 | data = skb_header_pointer(skb, 2, buflen, buf); | |
79 | __skb_pull(skb, 2 + ph->sb_len); | |
80 | return data; | |
81 | } | |
82 | ||
83 | static int pep_reply(struct sock *sk, struct sk_buff *oskb, | |
84 | u8 code, const void *data, int len, gfp_t priority) | |
85 | { | |
86 | const struct pnpipehdr *oph = pnp_hdr(oskb); | |
87 | struct pnpipehdr *ph; | |
88 | struct sk_buff *skb; | |
89 | ||
90 | skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority); | |
91 | if (!skb) | |
92 | return -ENOMEM; | |
93 | skb_set_owner_w(skb, sk); | |
94 | ||
95 | skb_reserve(skb, MAX_PNPIPE_HEADER); | |
96 | __skb_put(skb, len); | |
97 | skb_copy_to_linear_data(skb, data, len); | |
98 | __skb_push(skb, sizeof(*ph)); | |
99 | skb_reset_transport_header(skb); | |
100 | ph = pnp_hdr(skb); | |
101 | ph->utid = oph->utid; | |
102 | ph->message_id = oph->message_id + 1; /* REQ -> RESP */ | |
103 | ph->pipe_handle = oph->pipe_handle; | |
104 | ph->error_code = code; | |
105 | ||
106 | return pn_skb_send(sk, skb, &pipe_srv); | |
107 | } | |
108 | ||
109 | #define PAD 0x00 | |
110 | static int pep_accept_conn(struct sock *sk, struct sk_buff *skb) | |
111 | { | |
112 | static const u8 data[20] = { | |
113 | PAD, PAD, PAD, 2 /* sub-blocks */, | |
114 | PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD, | |
115 | PN_MULTI_CREDIT_FLOW_CONTROL, | |
116 | PN_ONE_CREDIT_FLOW_CONTROL, | |
117 | PN_LEGACY_FLOW_CONTROL, | |
118 | PAD, | |
119 | PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD, | |
120 | PN_MULTI_CREDIT_FLOW_CONTROL, | |
121 | PN_ONE_CREDIT_FLOW_CONTROL, | |
122 | PN_LEGACY_FLOW_CONTROL, | |
123 | PAD, | |
124 | }; | |
125 | ||
126 | might_sleep(); | |
127 | return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data), | |
128 | GFP_KERNEL); | |
129 | } | |
130 | ||
131 | static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code) | |
132 | { | |
133 | static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ }; | |
134 | WARN_ON(code == PN_PIPE_NO_ERROR); | |
135 | return pep_reply(sk, skb, code, data, sizeof(data), GFP_ATOMIC); | |
136 | } | |
137 | ||
138 | /* Control requests are not sent by the pipe service and have a specific | |
139 | * message format. */ | |
c41bd97f RDC |
140 | static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code, |
141 | gfp_t priority) | |
9641458d RDC |
142 | { |
143 | const struct pnpipehdr *oph = pnp_hdr(oskb); | |
144 | struct sk_buff *skb; | |
145 | struct pnpipehdr *ph; | |
146 | struct sockaddr_pn dst; | |
147 | ||
c41bd97f | 148 | skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority); |
9641458d RDC |
149 | if (!skb) |
150 | return -ENOMEM; | |
151 | skb_set_owner_w(skb, sk); | |
152 | ||
153 | skb_reserve(skb, MAX_PHONET_HEADER); | |
154 | ph = (struct pnpipehdr *)skb_put(skb, sizeof(*ph) + 4); | |
155 | ||
156 | ph->utid = oph->utid; | |
157 | ph->message_id = PNS_PEP_CTRL_RESP; | |
158 | ph->pipe_handle = oph->pipe_handle; | |
159 | ph->data[0] = oph->data[1]; /* CTRL id */ | |
160 | ph->data[1] = oph->data[0]; /* PEP type */ | |
161 | ph->data[2] = code; /* error code, at an usual offset */ | |
162 | ph->data[3] = PAD; | |
163 | ph->data[4] = PAD; | |
164 | ||
165 | pn_skb_get_src_sockaddr(oskb, &dst); | |
166 | return pn_skb_send(sk, skb, &dst); | |
167 | } | |
168 | ||
169 | static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority) | |
170 | { | |
171 | struct pep_sock *pn = pep_sk(sk); | |
172 | struct pnpipehdr *ph; | |
173 | struct sk_buff *skb; | |
174 | ||
175 | skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority); | |
176 | if (!skb) | |
177 | return -ENOMEM; | |
178 | skb_set_owner_w(skb, sk); | |
179 | ||
180 | skb_reserve(skb, MAX_PNPIPE_HEADER + 4); | |
181 | __skb_push(skb, sizeof(*ph) + 4); | |
182 | skb_reset_transport_header(skb); | |
183 | ph = pnp_hdr(skb); | |
184 | ph->utid = 0; | |
185 | ph->message_id = PNS_PEP_STATUS_IND; | |
186 | ph->pipe_handle = pn->pipe_handle; | |
187 | ph->pep_type = PN_PEP_TYPE_COMMON; | |
188 | ph->data[1] = type; | |
189 | ph->data[2] = PAD; | |
190 | ph->data[3] = PAD; | |
191 | ph->data[4] = status; | |
192 | ||
193 | return pn_skb_send(sk, skb, &pipe_srv); | |
194 | } | |
195 | ||
196 | /* Send our RX flow control information to the sender. | |
197 | * Socket must be locked. */ | |
198 | static void pipe_grant_credits(struct sock *sk) | |
199 | { | |
200 | struct pep_sock *pn = pep_sk(sk); | |
201 | ||
202 | BUG_ON(sk->sk_state != TCP_ESTABLISHED); | |
203 | ||
204 | switch (pn->rx_fc) { | |
205 | case PN_LEGACY_FLOW_CONTROL: /* TODO */ | |
206 | break; | |
207 | case PN_ONE_CREDIT_FLOW_CONTROL: | |
208 | pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL, | |
209 | PEP_IND_READY, GFP_ATOMIC); | |
210 | pn->rx_credits = 1; | |
211 | break; | |
212 | case PN_MULTI_CREDIT_FLOW_CONTROL: | |
213 | if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX) | |
214 | break; | |
215 | if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS, | |
216 | CREDITS_MAX - pn->rx_credits, | |
217 | GFP_ATOMIC) == 0) | |
218 | pn->rx_credits = CREDITS_MAX; | |
219 | break; | |
220 | } | |
221 | } | |
222 | ||
223 | static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb) | |
224 | { | |
225 | struct pep_sock *pn = pep_sk(sk); | |
226 | struct pnpipehdr *hdr = pnp_hdr(skb); | |
227 | ||
228 | if (!pskb_may_pull(skb, sizeof(*hdr) + 4)) | |
229 | return -EINVAL; | |
230 | ||
231 | if (hdr->data[0] != PN_PEP_TYPE_COMMON) { | |
232 | LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n", | |
233 | (unsigned)hdr->data[0]); | |
234 | return -EOPNOTSUPP; | |
235 | } | |
236 | ||
237 | switch (hdr->data[1]) { | |
238 | case PN_PEP_IND_FLOW_CONTROL: | |
239 | switch (pn->tx_fc) { | |
240 | case PN_LEGACY_FLOW_CONTROL: | |
241 | switch (hdr->data[4]) { | |
242 | case PEP_IND_BUSY: | |
243 | pn->tx_credits = 0; | |
244 | break; | |
245 | case PEP_IND_READY: | |
246 | pn->tx_credits = 1; | |
247 | break; | |
248 | } | |
249 | break; | |
250 | case PN_ONE_CREDIT_FLOW_CONTROL: | |
251 | if (hdr->data[4] == PEP_IND_READY) | |
252 | pn->tx_credits = 1; | |
253 | break; | |
254 | } | |
255 | break; | |
256 | ||
257 | case PN_PEP_IND_ID_MCFC_GRANT_CREDITS: | |
258 | if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL) | |
259 | break; | |
260 | if (pn->tx_credits + hdr->data[4] > 0xff) | |
261 | pn->tx_credits = 0xff; | |
262 | else | |
263 | pn->tx_credits += hdr->data[4]; | |
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 (pn->tx_credits) | |
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); | |
c41bd97f | 309 | struct sk_buff_head *queue; |
9641458d RDC |
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 | 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: | |
c41bd97f RDC |
350 | if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) |
351 | break; | |
352 | __skb_pull(skb, 4); | |
353 | queue = &pn->ctrlreq_queue; | |
354 | goto queue; | |
9641458d RDC |
355 | |
356 | case PNS_PIPE_DATA: | |
357 | __skb_pull(skb, 3); /* Pipe data header */ | |
358 | if (!pn_flow_safe(pn->rx_fc)) { | |
359 | err = sock_queue_rcv_skb(sk, skb); | |
360 | if (!err) | |
361 | return 0; | |
362 | break; | |
363 | } | |
364 | ||
365 | if (pn->rx_credits == 0) { | |
366 | err = -ENOBUFS; | |
367 | break; | |
368 | } | |
369 | pn->rx_credits--; | |
c41bd97f RDC |
370 | queue = &sk->sk_receive_queue; |
371 | goto queue; | |
9641458d RDC |
372 | |
373 | case PNS_PEP_STATUS_IND: | |
374 | pipe_rcv_status(sk, skb); | |
375 | break; | |
376 | ||
377 | case PNS_PIPE_REDIRECTED_IND: | |
378 | err = pipe_rcv_created(sk, skb); | |
379 | break; | |
380 | ||
381 | case PNS_PIPE_CREATED_IND: | |
382 | err = pipe_rcv_created(sk, skb); | |
383 | if (err) | |
384 | break; | |
385 | /* fall through */ | |
386 | case PNS_PIPE_RESET_IND: | |
387 | if (!pn->init_enable) | |
388 | break; | |
389 | /* fall through */ | |
390 | case PNS_PIPE_ENABLED_IND: | |
391 | if (!pn_flow_safe(pn->tx_fc)) { | |
392 | pn->tx_credits = 1; | |
393 | sk->sk_write_space(sk); | |
394 | } | |
395 | if (sk->sk_state == TCP_ESTABLISHED) | |
396 | break; /* Nothing to do */ | |
397 | sk->sk_state = TCP_ESTABLISHED; | |
398 | pipe_grant_credits(sk); | |
399 | break; | |
400 | ||
401 | case PNS_PIPE_DISABLED_IND: | |
402 | sk->sk_state = TCP_SYN_RECV; | |
403 | pn->rx_credits = 0; | |
404 | break; | |
405 | ||
406 | default: | |
407 | LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n", | |
408 | hdr->message_id); | |
409 | err = -EINVAL; | |
410 | } | |
411 | out: | |
412 | kfree_skb(skb); | |
413 | return err; | |
c41bd97f RDC |
414 | |
415 | queue: | |
416 | skb->dev = NULL; | |
417 | skb_set_owner_r(skb, sk); | |
418 | err = skb->len; | |
419 | skb_queue_tail(queue, skb); | |
420 | if (!sock_flag(sk, SOCK_DEAD)) | |
421 | sk->sk_data_ready(sk, err); | |
422 | return 0; | |
9641458d RDC |
423 | } |
424 | ||
425 | /* Destroy connected sock. */ | |
426 | static void pipe_destruct(struct sock *sk) | |
427 | { | |
c41bd97f RDC |
428 | struct pep_sock *pn = pep_sk(sk); |
429 | ||
9641458d | 430 | skb_queue_purge(&sk->sk_receive_queue); |
c41bd97f | 431 | skb_queue_purge(&pn->ctrlreq_queue); |
9641458d RDC |
432 | } |
433 | ||
434 | static int pep_connreq_rcv(struct sock *sk, struct sk_buff *skb) | |
435 | { | |
436 | struct sock *newsk; | |
437 | struct pep_sock *newpn, *pn = pep_sk(sk); | |
438 | struct pnpipehdr *hdr; | |
439 | struct sockaddr_pn dst; | |
440 | u16 peer_type; | |
441 | u8 pipe_handle, enabled, n_sb; | |
442 | ||
443 | if (!pskb_pull(skb, sizeof(*hdr) + 4)) | |
444 | return -EINVAL; | |
445 | ||
446 | hdr = pnp_hdr(skb); | |
447 | pipe_handle = hdr->pipe_handle; | |
448 | switch (hdr->state_after_connect) { | |
449 | case PN_PIPE_DISABLE: | |
450 | enabled = 0; | |
451 | break; | |
452 | case PN_PIPE_ENABLE: | |
453 | enabled = 1; | |
454 | break; | |
455 | default: | |
456 | pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM); | |
457 | return -EINVAL; | |
458 | } | |
459 | peer_type = hdr->other_pep_type << 8; | |
460 | ||
461 | if (unlikely(sk->sk_state != TCP_LISTEN) || sk_acceptq_is_full(sk)) { | |
462 | pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE); | |
463 | return -ENOBUFS; | |
464 | } | |
465 | ||
466 | /* Parse sub-blocks (options) */ | |
467 | n_sb = hdr->data[4]; | |
468 | while (n_sb > 0) { | |
469 | u8 type, buf[1], len = sizeof(buf); | |
470 | const u8 *data = pep_get_sb(skb, &type, &len, buf); | |
471 | ||
472 | if (data == NULL) | |
473 | return -EINVAL; | |
474 | switch (type) { | |
475 | case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE: | |
476 | if (len < 1) | |
477 | return -EINVAL; | |
478 | peer_type = (peer_type & 0xff00) | data[0]; | |
479 | break; | |
480 | } | |
481 | n_sb--; | |
482 | } | |
483 | ||
484 | skb = skb_clone(skb, GFP_ATOMIC); | |
485 | if (!skb) | |
486 | return -ENOMEM; | |
487 | ||
488 | /* Create a new to-be-accepted sock */ | |
489 | newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_ATOMIC, sk->sk_prot); | |
490 | if (!newsk) { | |
491 | kfree_skb(skb); | |
492 | return -ENOMEM; | |
493 | } | |
494 | sock_init_data(NULL, newsk); | |
495 | newsk->sk_state = TCP_SYN_RECV; | |
496 | newsk->sk_backlog_rcv = pipe_do_rcv; | |
497 | newsk->sk_protocol = sk->sk_protocol; | |
498 | newsk->sk_destruct = pipe_destruct; | |
499 | ||
500 | newpn = pep_sk(newsk); | |
501 | pn_skb_get_dst_sockaddr(skb, &dst); | |
502 | newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst); | |
503 | newpn->pn_sk.resource = pn->pn_sk.resource; | |
c41bd97f | 504 | skb_queue_head_init(&newpn->ctrlreq_queue); |
9641458d RDC |
505 | newpn->pipe_handle = pipe_handle; |
506 | newpn->peer_type = peer_type; | |
507 | newpn->rx_credits = newpn->tx_credits = 0; | |
508 | newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL; | |
509 | newpn->init_enable = enabled; | |
510 | ||
511 | BUG_ON(!skb_queue_empty(&newsk->sk_receive_queue)); | |
512 | skb_queue_head(&newsk->sk_receive_queue, skb); | |
513 | if (!sock_flag(sk, SOCK_DEAD)) | |
514 | sk->sk_data_ready(sk, 0); | |
515 | ||
516 | sk_acceptq_added(sk); | |
517 | sk_add_node(newsk, &pn->ackq); | |
518 | return 0; | |
519 | } | |
520 | ||
521 | /* Listening sock must be locked */ | |
522 | static struct sock *pep_find_pipe(const struct hlist_head *hlist, | |
523 | const struct sockaddr_pn *dst, | |
524 | u8 pipe_handle) | |
525 | { | |
526 | struct hlist_node *node; | |
527 | struct sock *sknode; | |
528 | u16 dobj = pn_sockaddr_get_object(dst); | |
529 | ||
530 | sk_for_each(sknode, node, hlist) { | |
531 | struct pep_sock *pnnode = pep_sk(sknode); | |
532 | ||
533 | /* Ports match, but addresses might not: */ | |
534 | if (pnnode->pn_sk.sobject != dobj) | |
535 | continue; | |
536 | if (pnnode->pipe_handle != pipe_handle) | |
537 | continue; | |
538 | if (sknode->sk_state == TCP_CLOSE_WAIT) | |
539 | continue; | |
540 | ||
541 | sock_hold(sknode); | |
542 | return sknode; | |
543 | } | |
544 | return NULL; | |
545 | } | |
546 | ||
547 | /* | |
548 | * Deliver an skb to a listening sock. | |
549 | * Socket lock must be held. | |
550 | * We then queue the skb to the right connected sock (if any). | |
551 | */ | |
552 | static int pep_do_rcv(struct sock *sk, struct sk_buff *skb) | |
553 | { | |
554 | struct pep_sock *pn = pep_sk(sk); | |
555 | struct sock *sknode; | |
556 | struct pnpipehdr *hdr = pnp_hdr(skb); | |
557 | struct sockaddr_pn dst; | |
558 | int err = NET_RX_SUCCESS; | |
559 | u8 pipe_handle; | |
560 | ||
561 | if (!pskb_may_pull(skb, sizeof(*hdr))) | |
562 | goto drop; | |
563 | ||
564 | hdr = pnp_hdr(skb); | |
565 | pipe_handle = hdr->pipe_handle; | |
566 | if (pipe_handle == PN_PIPE_INVALID_HANDLE) | |
567 | goto drop; | |
568 | ||
569 | pn_skb_get_dst_sockaddr(skb, &dst); | |
570 | ||
571 | /* Look for an existing pipe handle */ | |
572 | sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle); | |
573 | if (sknode) | |
574 | return sk_receive_skb(sknode, skb, 1); | |
575 | ||
576 | /* Look for a pipe handle pending accept */ | |
577 | sknode = pep_find_pipe(&pn->ackq, &dst, pipe_handle); | |
578 | if (sknode) { | |
579 | sock_put(sknode); | |
580 | if (net_ratelimit()) | |
581 | printk(KERN_WARNING"Phonet unconnected PEP ignored"); | |
582 | err = NET_RX_DROP; | |
583 | goto drop; | |
584 | } | |
585 | ||
586 | switch (hdr->message_id) { | |
587 | case PNS_PEP_CONNECT_REQ: | |
588 | err = pep_connreq_rcv(sk, skb); | |
589 | break; | |
590 | ||
591 | case PNS_PEP_DISCONNECT_REQ: | |
592 | pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); | |
593 | break; | |
594 | ||
595 | case PNS_PEP_CTRL_REQ: | |
c41bd97f | 596 | pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC); |
9641458d RDC |
597 | break; |
598 | ||
599 | case PNS_PEP_RESET_REQ: | |
600 | case PNS_PEP_ENABLE_REQ: | |
601 | case PNS_PEP_DISABLE_REQ: | |
602 | /* invalid handle is not even allowed here! */ | |
603 | default: | |
604 | err = NET_RX_DROP; | |
605 | } | |
606 | drop: | |
607 | kfree_skb(skb); | |
608 | return err; | |
609 | } | |
610 | ||
611 | /* associated socket ceases to exist */ | |
612 | static void pep_sock_close(struct sock *sk, long timeout) | |
613 | { | |
614 | struct pep_sock *pn = pep_sk(sk); | |
615 | ||
616 | sk_common_release(sk); | |
617 | ||
618 | lock_sock(sk); | |
619 | if (sk->sk_state == TCP_LISTEN) { | |
620 | /* Destroy the listen queue */ | |
621 | struct sock *sknode; | |
622 | struct hlist_node *p, *n; | |
623 | ||
624 | sk_for_each_safe(sknode, p, n, &pn->ackq) | |
625 | sk_del_node_init(sknode); | |
626 | sk->sk_state = TCP_CLOSE; | |
627 | } | |
628 | release_sock(sk); | |
629 | } | |
630 | ||
631 | static int pep_wait_connreq(struct sock *sk, int noblock) | |
632 | { | |
633 | struct task_struct *tsk = current; | |
634 | struct pep_sock *pn = pep_sk(sk); | |
635 | long timeo = sock_rcvtimeo(sk, noblock); | |
636 | ||
637 | for (;;) { | |
638 | DEFINE_WAIT(wait); | |
639 | ||
640 | if (sk->sk_state != TCP_LISTEN) | |
641 | return -EINVAL; | |
642 | if (!hlist_empty(&pn->ackq)) | |
643 | break; | |
644 | if (!timeo) | |
645 | return -EWOULDBLOCK; | |
646 | if (signal_pending(tsk)) | |
647 | return sock_intr_errno(timeo); | |
648 | ||
649 | prepare_to_wait_exclusive(&sk->sk_socket->wait, &wait, | |
650 | TASK_INTERRUPTIBLE); | |
651 | release_sock(sk); | |
652 | timeo = schedule_timeout(timeo); | |
653 | lock_sock(sk); | |
654 | finish_wait(&sk->sk_socket->wait, &wait); | |
655 | } | |
656 | ||
657 | return 0; | |
658 | } | |
659 | ||
660 | static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp) | |
661 | { | |
662 | struct pep_sock *pn = pep_sk(sk); | |
663 | struct sock *newsk = NULL; | |
664 | struct sk_buff *oskb; | |
665 | int err; | |
666 | ||
667 | lock_sock(sk); | |
668 | err = pep_wait_connreq(sk, flags & O_NONBLOCK); | |
669 | if (err) | |
670 | goto out; | |
671 | ||
672 | newsk = __sk_head(&pn->ackq); | |
673 | ||
674 | oskb = skb_dequeue(&newsk->sk_receive_queue); | |
675 | err = pep_accept_conn(newsk, oskb); | |
676 | if (err) { | |
677 | skb_queue_head(&newsk->sk_receive_queue, oskb); | |
678 | newsk = NULL; | |
679 | goto out; | |
680 | } | |
681 | ||
682 | sock_hold(sk); | |
683 | pep_sk(newsk)->listener = sk; | |
684 | ||
685 | sock_hold(newsk); | |
686 | sk_del_node_init(newsk); | |
687 | sk_acceptq_removed(sk); | |
688 | sk_add_node(newsk, &pn->hlist); | |
689 | __sock_put(newsk); | |
690 | ||
691 | out: | |
692 | release_sock(sk); | |
693 | *errp = err; | |
694 | return newsk; | |
695 | } | |
696 | ||
697 | static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg) | |
698 | { | |
c41bd97f | 699 | struct pep_sock *pn = pep_sk(sk); |
9641458d RDC |
700 | int answ; |
701 | ||
702 | switch (cmd) { | |
703 | case SIOCINQ: | |
704 | if (sk->sk_state == TCP_LISTEN) | |
705 | return -EINVAL; | |
706 | ||
707 | lock_sock(sk); | |
c41bd97f RDC |
708 | if (sock_flag(sk, SOCK_URGINLINE) |
709 | && !skb_queue_empty(&pn->ctrlreq_queue)) | |
710 | answ = skb_peek(&pn->ctrlreq_queue)->len; | |
711 | else if (!skb_queue_empty(&sk->sk_receive_queue)) | |
9641458d RDC |
712 | answ = skb_peek(&sk->sk_receive_queue)->len; |
713 | else | |
714 | answ = 0; | |
715 | release_sock(sk); | |
716 | return put_user(answ, (int __user *)arg); | |
717 | } | |
718 | ||
719 | return -ENOIOCTLCMD; | |
720 | } | |
721 | ||
722 | static int pep_init(struct sock *sk) | |
723 | { | |
724 | struct pep_sock *pn = pep_sk(sk); | |
725 | ||
726 | INIT_HLIST_HEAD(&pn->ackq); | |
727 | INIT_HLIST_HEAD(&pn->hlist); | |
c41bd97f | 728 | skb_queue_head_init(&pn->ctrlreq_queue); |
9641458d RDC |
729 | pn->pipe_handle = PN_PIPE_INVALID_HANDLE; |
730 | return 0; | |
731 | } | |
732 | ||
733 | static int pep_sendmsg(struct kiocb *iocb, struct sock *sk, | |
734 | struct msghdr *msg, size_t len) | |
735 | { | |
736 | struct pep_sock *pn = pep_sk(sk); | |
737 | struct sk_buff *skb = NULL; | |
738 | struct pnpipehdr *ph; | |
739 | long timeo; | |
740 | int flags = msg->msg_flags; | |
741 | int err, done; | |
742 | ||
743 | if (msg->msg_flags & MSG_OOB || !(msg->msg_flags & MSG_EOR)) | |
744 | return -EOPNOTSUPP; | |
745 | ||
746 | lock_sock(sk); | |
747 | timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); | |
748 | if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) { | |
749 | err = -ENOTCONN; | |
750 | goto out; | |
751 | } | |
752 | if (sk->sk_state != TCP_ESTABLISHED) { | |
753 | /* Wait until the pipe gets to enabled state */ | |
754 | disabled: | |
755 | err = sk_stream_wait_connect(sk, &timeo); | |
756 | if (err) | |
757 | goto out; | |
758 | ||
759 | if (sk->sk_state == TCP_CLOSE_WAIT) { | |
760 | err = -ECONNRESET; | |
761 | goto out; | |
762 | } | |
763 | } | |
764 | BUG_ON(sk->sk_state != TCP_ESTABLISHED); | |
765 | ||
766 | /* Wait until flow control allows TX */ | |
767 | done = pn->tx_credits > 0; | |
768 | while (!done) { | |
769 | DEFINE_WAIT(wait); | |
770 | ||
771 | if (!timeo) { | |
772 | err = -EAGAIN; | |
773 | goto out; | |
774 | } | |
775 | if (signal_pending(current)) { | |
776 | err = sock_intr_errno(timeo); | |
777 | goto out; | |
778 | } | |
779 | ||
780 | prepare_to_wait(&sk->sk_socket->wait, &wait, | |
781 | TASK_INTERRUPTIBLE); | |
782 | done = sk_wait_event(sk, &timeo, pn->tx_credits > 0); | |
783 | finish_wait(&sk->sk_socket->wait, &wait); | |
784 | ||
785 | if (sk->sk_state != TCP_ESTABLISHED) | |
786 | goto disabled; | |
787 | } | |
788 | ||
789 | if (!skb) { | |
790 | skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len, | |
791 | flags & MSG_DONTWAIT, &err); | |
792 | if (skb == NULL) | |
793 | goto out; | |
794 | skb_reserve(skb, MAX_PHONET_HEADER + 3); | |
795 | ||
796 | if (sk->sk_state != TCP_ESTABLISHED || !pn->tx_credits) | |
797 | goto disabled; /* sock_alloc_send_skb might sleep */ | |
798 | } | |
799 | ||
800 | err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); | |
801 | if (err < 0) | |
802 | goto out; | |
803 | ||
804 | __skb_push(skb, 3); | |
805 | skb_reset_transport_header(skb); | |
806 | ph = pnp_hdr(skb); | |
807 | ph->utid = 0; | |
808 | ph->message_id = PNS_PIPE_DATA; | |
809 | ph->pipe_handle = pn->pipe_handle; | |
810 | if (pn_flow_safe(pn->tx_fc)) /* credit-based flow control */ | |
811 | pn->tx_credits--; | |
812 | ||
813 | err = pn_skb_send(sk, skb, &pipe_srv); | |
814 | if (err >= 0) | |
815 | err = len; /* success! */ | |
816 | skb = NULL; | |
817 | out: | |
818 | release_sock(sk); | |
819 | kfree_skb(skb); | |
820 | return err; | |
821 | } | |
822 | ||
823 | static int pep_recvmsg(struct kiocb *iocb, struct sock *sk, | |
824 | struct msghdr *msg, size_t len, int noblock, | |
825 | int flags, int *addr_len) | |
826 | { | |
827 | struct sk_buff *skb; | |
828 | int err; | |
829 | ||
9641458d RDC |
830 | if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE))) |
831 | return -ENOTCONN; | |
832 | ||
c41bd97f RDC |
833 | if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) { |
834 | /* Dequeue and acknowledge control request */ | |
835 | struct pep_sock *pn = pep_sk(sk); | |
836 | ||
837 | skb = skb_dequeue(&pn->ctrlreq_queue); | |
838 | if (skb) { | |
839 | pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR, | |
840 | GFP_KERNEL); | |
841 | msg->msg_flags |= MSG_OOB; | |
842 | goto copy; | |
843 | } | |
844 | if (flags & MSG_OOB) | |
845 | return -EINVAL; | |
846 | } | |
847 | ||
9641458d RDC |
848 | skb = skb_recv_datagram(sk, flags, noblock, &err); |
849 | lock_sock(sk); | |
850 | if (skb == NULL) { | |
851 | if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT) | |
852 | err = -ECONNRESET; | |
853 | release_sock(sk); | |
854 | return err; | |
855 | } | |
856 | ||
857 | if (sk->sk_state == TCP_ESTABLISHED) | |
858 | pipe_grant_credits(sk); | |
859 | release_sock(sk); | |
c41bd97f | 860 | copy: |
9641458d | 861 | msg->msg_flags |= MSG_EOR; |
9641458d RDC |
862 | if (skb->len > len) |
863 | msg->msg_flags |= MSG_TRUNC; | |
864 | else | |
865 | len = skb->len; | |
866 | ||
867 | err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len); | |
868 | if (!err) | |
869 | err = (flags & MSG_TRUNC) ? skb->len : len; | |
870 | ||
871 | skb_free_datagram(sk, skb); | |
872 | return err; | |
873 | } | |
874 | ||
875 | static void pep_sock_unhash(struct sock *sk) | |
876 | { | |
877 | struct pep_sock *pn = pep_sk(sk); | |
878 | struct sock *skparent = NULL; | |
879 | ||
880 | lock_sock(sk); | |
881 | if ((1 << sk->sk_state) & ~(TCPF_CLOSE|TCPF_LISTEN)) { | |
882 | skparent = pn->listener; | |
883 | sk_del_node_init(sk); | |
884 | release_sock(sk); | |
885 | ||
886 | sk = skparent; | |
887 | pn = pep_sk(skparent); | |
888 | lock_sock(sk); | |
889 | } | |
890 | /* Unhash a listening sock only when it is closed | |
891 | * and all of its active connected pipes are closed. */ | |
892 | if (hlist_empty(&pn->hlist)) | |
893 | pn_sock_unhash(&pn->pn_sk.sk); | |
894 | release_sock(sk); | |
895 | ||
896 | if (skparent) | |
897 | sock_put(skparent); | |
898 | } | |
899 | ||
900 | static struct proto pep_proto = { | |
901 | .close = pep_sock_close, | |
902 | .accept = pep_sock_accept, | |
903 | .ioctl = pep_ioctl, | |
904 | .init = pep_init, | |
905 | .sendmsg = pep_sendmsg, | |
906 | .recvmsg = pep_recvmsg, | |
907 | .backlog_rcv = pep_do_rcv, | |
908 | .hash = pn_sock_hash, | |
909 | .unhash = pep_sock_unhash, | |
910 | .get_port = pn_sock_get_port, | |
911 | .obj_size = sizeof(struct pep_sock), | |
912 | .owner = THIS_MODULE, | |
913 | .name = "PNPIPE", | |
914 | }; | |
915 | ||
916 | static struct phonet_protocol pep_pn_proto = { | |
917 | .ops = &phonet_stream_ops, | |
918 | .prot = &pep_proto, | |
919 | .sock_type = SOCK_SEQPACKET, | |
920 | }; | |
921 | ||
922 | static int __init pep_register(void) | |
923 | { | |
924 | return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto); | |
925 | } | |
926 | ||
927 | static void __exit pep_unregister(void) | |
928 | { | |
929 | phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto); | |
930 | } | |
931 | ||
932 | module_init(pep_register); | |
933 | module_exit(pep_unregister); | |
934 | MODULE_AUTHOR("Remi Denis-Courmont, Nokia"); | |
935 | MODULE_DESCRIPTION("Phonet pipe protocol"); | |
936 | MODULE_LICENSE("GPL"); | |
937 | MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE); |