Magellan Linux

Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/net/sctp/endpointola.c

Parent Directory Parent Directory | Revision Log Revision Log


Revision 630 - (show annotations) (download)
Wed Mar 4 11:03:09 2009 UTC (15 years, 3 months ago) by niro
File MIME type: text/plain
File size: 10820 byte(s)
Tag kernel26-2.6.12-alx-r9
1 /* SCTP kernel reference Implementation
2 * Copyright (c) 1999-2000 Cisco, Inc.
3 * Copyright (c) 1999-2001 Motorola, Inc.
4 * Copyright (c) 2001-2002 International Business Machines, Corp.
5 * Copyright (c) 2001 Intel Corp.
6 * Copyright (c) 2001 Nokia, Inc.
7 * Copyright (c) 2001 La Monte H.P. Yarroll
8 *
9 * This file is part of the SCTP kernel reference Implementation
10 *
11 * This abstraction represents an SCTP endpoint.
12 *
13 * This file is part of the implementation of the add-IP extension,
14 * based on <draft-ietf-tsvwg-addip-sctp-02.txt> June 29, 2001,
15 * for the SCTP kernel reference Implementation.
16 *
17 * The SCTP reference implementation is free software;
18 * you can redistribute it and/or modify it under the terms of
19 * the GNU General Public License as published by
20 * the Free Software Foundation; either version 2, or (at your option)
21 * any later version.
22 *
23 * The SCTP reference implementation is distributed in the hope that it
24 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
25 * ************************
26 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
27 * See the GNU General Public License for more details.
28 *
29 * You should have received a copy of the GNU General Public License
30 * along with GNU CC; see the file COPYING. If not, write to
31 * the Free Software Foundation, 59 Temple Place - Suite 330,
32 * Boston, MA 02111-1307, USA.
33 *
34 * Please send any bug reports or fixes you make to the
35 * email address(es):
36 * lksctp developers <lksctp-developers@lists.sourceforge.net>
37 *
38 * Or submit a bug report through the following website:
39 * http://www.sf.net/projects/lksctp
40 *
41 * Written or modified by:
42 * La Monte H.P. Yarroll <piggy@acm.org>
43 * Karl Knutson <karl@athena.chicago.il.us>
44 * Jon Grimm <jgrimm@austin.ibm.com>
45 * Daisy Chang <daisyc@us.ibm.com>
46 * Dajiang Zhang <dajiang.zhang@nokia.com>
47 *
48 * Any bugs reported given to us we will try to fix... any fixes shared will
49 * be incorporated into the next SCTP release.
50 */
51
52 #include <linux/types.h>
53 #include <linux/sched.h>
54 #include <linux/slab.h>
55 #include <linux/in.h>
56 #include <linux/random.h> /* get_random_bytes() */
57 #include <linux/crypto.h>
58 #include <net/sock.h>
59 #include <net/ipv6.h>
60 #include <net/sctp/sctp.h>
61 #include <net/sctp/sm.h>
62
63 /* Forward declarations for internal helpers. */
64 static void sctp_endpoint_bh_rcv(struct sctp_endpoint *ep);
65
66 /*
67 * Initialize the base fields of the endpoint structure.
68 */
69 static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
70 struct sock *sk, int gfp)
71 {
72 struct sctp_sock *sp = sctp_sk(sk);
73 memset(ep, 0, sizeof(struct sctp_endpoint));
74
75 /* Initialize the base structure. */
76 /* What type of endpoint are we? */
77 ep->base.type = SCTP_EP_TYPE_SOCKET;
78
79 /* Initialize the basic object fields. */
80 atomic_set(&ep->base.refcnt, 1);
81 ep->base.dead = 0;
82 ep->base.malloced = 1;
83
84 /* Create an input queue. */
85 sctp_inq_init(&ep->base.inqueue);
86
87 /* Set its top-half handler */
88 sctp_inq_set_th_handler(&ep->base.inqueue,
89 (void (*)(void *))sctp_endpoint_bh_rcv, ep);
90
91 /* Initialize the bind addr area */
92 sctp_bind_addr_init(&ep->base.bind_addr, 0);
93 rwlock_init(&ep->base.addr_lock);
94
95 /* Remember who we are attached to. */
96 ep->base.sk = sk;
97 sock_hold(ep->base.sk);
98
99 /* Create the lists of associations. */
100 INIT_LIST_HEAD(&ep->asocs);
101
102 /* Set up the base timeout information. */
103 ep->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
104 ep->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
105 SCTP_DEFAULT_TIMEOUT_T1_COOKIE;
106 ep->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
107 SCTP_DEFAULT_TIMEOUT_T1_INIT;
108 ep->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] =
109 msecs_to_jiffies(sp->rtoinfo.srto_initial);
110 ep->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
111 ep->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0;
112
113 /* sctpimpguide-05 Section 2.12.2
114 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
115 * recommended value of 5 times 'RTO.Max'.
116 */
117 ep->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
118 = 5 * msecs_to_jiffies(sp->rtoinfo.srto_max);
119
120 ep->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] =
121 SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
122 ep->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
123 SCTP_DEFAULT_TIMEOUT_SACK;
124 ep->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
125 sp->autoclose * HZ;
126
127 /* Use SCTP specific send buffer space queues. */
128 ep->sndbuf_policy = sctp_sndbuf_policy;
129 sk->sk_write_space = sctp_write_space;
130 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
131
132 /* Initialize the secret key used with cookie. */
133 get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
134 ep->last_key = ep->current_key = 0;
135 ep->key_changed_at = jiffies;
136
137 ep->debug_name = "unnamedEndpoint";
138 return ep;
139 }
140
141 /* Create a sctp_endpoint with all that boring stuff initialized.
142 * Returns NULL if there isn't enough memory.
143 */
144 struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, int gfp)
145 {
146 struct sctp_endpoint *ep;
147
148 /* Build a local endpoint. */
149 ep = t_new(struct sctp_endpoint, gfp);
150 if (!ep)
151 goto fail;
152 if (!sctp_endpoint_init(ep, sk, gfp))
153 goto fail_init;
154 ep->base.malloced = 1;
155 SCTP_DBG_OBJCNT_INC(ep);
156 return ep;
157
158 fail_init:
159 kfree(ep);
160 fail:
161 return NULL;
162 }
163
164 /* Add an association to an endpoint. */
165 void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
166 struct sctp_association *asoc)
167 {
168 struct sock *sk = ep->base.sk;
169
170 /* Now just add it to our list of asocs */
171 list_add_tail(&asoc->asocs, &ep->asocs);
172
173 /* Increment the backlog value for a TCP-style listening socket. */
174 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
175 sk->sk_ack_backlog++;
176 }
177
178 /* Free the endpoint structure. Delay cleanup until
179 * all users have released their reference count on this structure.
180 */
181 void sctp_endpoint_free(struct sctp_endpoint *ep)
182 {
183 ep->base.dead = 1;
184 sctp_endpoint_put(ep);
185 }
186
187 /* Final destructor for endpoint. */
188 static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
189 {
190 SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
191
192 ep->base.sk->sk_state = SCTP_SS_CLOSED;
193
194 /* Unlink this endpoint, so we can't find it again! */
195 sctp_unhash_endpoint(ep);
196
197 /* Free up the HMAC transform. */
198 if (sctp_sk(ep->base.sk)->hmac)
199 sctp_crypto_free_tfm(sctp_sk(ep->base.sk)->hmac);
200
201 /* Cleanup. */
202 sctp_inq_free(&ep->base.inqueue);
203 sctp_bind_addr_free(&ep->base.bind_addr);
204
205 /* Remove and free the port */
206 if (sctp_sk(ep->base.sk)->bind_hash)
207 sctp_put_port(ep->base.sk);
208
209 /* Give up our hold on the sock. */
210 if (ep->base.sk)
211 sock_put(ep->base.sk);
212
213 /* Finally, free up our memory. */
214 if (ep->base.malloced) {
215 kfree(ep);
216 SCTP_DBG_OBJCNT_DEC(ep);
217 }
218 }
219
220 /* Hold a reference to an endpoint. */
221 void sctp_endpoint_hold(struct sctp_endpoint *ep)
222 {
223 atomic_inc(&ep->base.refcnt);
224 }
225
226 /* Release a reference to an endpoint and clean up if there are
227 * no more references.
228 */
229 void sctp_endpoint_put(struct sctp_endpoint *ep)
230 {
231 if (atomic_dec_and_test(&ep->base.refcnt))
232 sctp_endpoint_destroy(ep);
233 }
234
235 /* Is this the endpoint we are looking for? */
236 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
237 const union sctp_addr *laddr)
238 {
239 struct sctp_endpoint *retval;
240
241 sctp_read_lock(&ep->base.addr_lock);
242 if (ep->base.bind_addr.port == laddr->v4.sin_port) {
243 if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
244 sctp_sk(ep->base.sk))) {
245 retval = ep;
246 goto out;
247 }
248 }
249
250 retval = NULL;
251
252 out:
253 sctp_read_unlock(&ep->base.addr_lock);
254 return retval;
255 }
256
257 /* Find the association that goes with this chunk.
258 * We do a linear search of the associations for this endpoint.
259 * We return the matching transport address too.
260 */
261 static struct sctp_association *__sctp_endpoint_lookup_assoc(
262 const struct sctp_endpoint *ep,
263 const union sctp_addr *paddr,
264 struct sctp_transport **transport)
265 {
266 int rport;
267 struct sctp_association *asoc;
268 struct list_head *pos;
269
270 rport = paddr->v4.sin_port;
271
272 list_for_each(pos, &ep->asocs) {
273 asoc = list_entry(pos, struct sctp_association, asocs);
274 if (rport == asoc->peer.port) {
275 sctp_read_lock(&asoc->base.addr_lock);
276 *transport = sctp_assoc_lookup_paddr(asoc, paddr);
277 sctp_read_unlock(&asoc->base.addr_lock);
278
279 if (*transport)
280 return asoc;
281 }
282 }
283
284 *transport = NULL;
285 return NULL;
286 }
287
288 /* Lookup association on an endpoint based on a peer address. BH-safe. */
289 struct sctp_association *sctp_endpoint_lookup_assoc(
290 const struct sctp_endpoint *ep,
291 const union sctp_addr *paddr,
292 struct sctp_transport **transport)
293 {
294 struct sctp_association *asoc;
295
296 sctp_local_bh_disable();
297 asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
298 sctp_local_bh_enable();
299
300 return asoc;
301 }
302
303 /* Look for any peeled off association from the endpoint that matches the
304 * given peer address.
305 */
306 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
307 const union sctp_addr *paddr)
308 {
309 struct list_head *pos;
310 struct sctp_sockaddr_entry *addr;
311 struct sctp_bind_addr *bp;
312
313 sctp_read_lock(&ep->base.addr_lock);
314 bp = &ep->base.bind_addr;
315 list_for_each(pos, &bp->address_list) {
316 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
317 if (sctp_has_association(&addr->a, paddr)) {
318 sctp_read_unlock(&ep->base.addr_lock);
319 return 1;
320 }
321 }
322 sctp_read_unlock(&ep->base.addr_lock);
323
324 return 0;
325 }
326
327 /* Do delayed input processing. This is scheduled by sctp_rcv().
328 * This may be called on BH or task time.
329 */
330 static void sctp_endpoint_bh_rcv(struct sctp_endpoint *ep)
331 {
332 struct sctp_association *asoc;
333 struct sock *sk;
334 struct sctp_transport *transport;
335 struct sctp_chunk *chunk;
336 struct sctp_inq *inqueue;
337 sctp_subtype_t subtype;
338 sctp_state_t state;
339 int error = 0;
340
341 if (ep->base.dead)
342 return;
343
344 asoc = NULL;
345 inqueue = &ep->base.inqueue;
346 sk = ep->base.sk;
347
348 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
349 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
350
351 /* We might have grown an association since last we
352 * looked, so try again.
353 *
354 * This happens when we've just processed our
355 * COOKIE-ECHO chunk.
356 */
357 if (NULL == chunk->asoc) {
358 asoc = sctp_endpoint_lookup_assoc(ep,
359 sctp_source(chunk),
360 &transport);
361 chunk->asoc = asoc;
362 chunk->transport = transport;
363 }
364
365 state = asoc ? asoc->state : SCTP_STATE_CLOSED;
366
367 /* Remember where the last DATA chunk came from so we
368 * know where to send the SACK.
369 */
370 if (asoc && sctp_chunk_is_data(chunk))
371 asoc->peer.last_data_from = chunk->transport;
372 else
373 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);
374
375 if (chunk->transport)
376 chunk->transport->last_time_heard = jiffies;
377
378 error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, state,
379 ep, asoc, chunk, GFP_ATOMIC);
380
381 if (error && chunk)
382 chunk->pdiscard = 1;
383
384 /* Check to see if the endpoint is freed in response to
385 * the incoming chunk. If so, get out of the while loop.
386 */
387 if (!sctp_sk(sk)->ep)
388 break;
389 }
390 }