[SCTP]: Remove temporary associations from backlog and hash.
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / sctp / endpointola.c
CommitLineData
1da177e4
LT
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. */
64static void sctp_endpoint_bh_rcv(struct sctp_endpoint *ep);
65
66/*
67 * Initialize the base fields of the endpoint structure.
68 */
69static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
3182cd84 70 struct sock *sk,
dd0fc66f 71 gfp_t gfp)
1da177e4 72{
1da177e4
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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
1da177e4 102 /* Use SCTP specific send buffer space queues. */
4eb701df 103 ep->sndbuf_policy = sctp_sndbuf_policy;
1da177e4
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104 sk->sk_write_space = sctp_write_space;
105 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
106
049b3ff5
NH
107 /* Get the receive buffer policy for this endpoint */
108 ep->rcvbuf_policy = sctp_rcvbuf_policy;
109
1da177e4
LT
110 /* Initialize the secret key used with cookie. */
111 get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
112 ep->last_key = ep->current_key = 0;
113 ep->key_changed_at = jiffies;
114
1da177e4
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115 return ep;
116}
117
118/* Create a sctp_endpoint with all that boring stuff initialized.
119 * Returns NULL if there isn't enough memory.
120 */
dd0fc66f 121struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp)
1da177e4
LT
122{
123 struct sctp_endpoint *ep;
124
125 /* Build a local endpoint. */
126 ep = t_new(struct sctp_endpoint, gfp);
127 if (!ep)
128 goto fail;
129 if (!sctp_endpoint_init(ep, sk, gfp))
130 goto fail_init;
131 ep->base.malloced = 1;
132 SCTP_DBG_OBJCNT_INC(ep);
133 return ep;
134
135fail_init:
136 kfree(ep);
137fail:
138 return NULL;
139}
140
141/* Add an association to an endpoint. */
142void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
143 struct sctp_association *asoc)
144{
145 struct sock *sk = ep->base.sk;
146
de76e695
VY
147 /* If this is a temporary association, don't bother
148 * since we'll be removing it shortly and don't
149 * want anyone to find it anyway.
150 */
151 if (asoc->temp)
152 return;
153
1da177e4
LT
154 /* Now just add it to our list of asocs */
155 list_add_tail(&asoc->asocs, &ep->asocs);
156
157 /* Increment the backlog value for a TCP-style listening socket. */
158 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
159 sk->sk_ack_backlog++;
160}
161
162/* Free the endpoint structure. Delay cleanup until
163 * all users have released their reference count on this structure.
164 */
165void sctp_endpoint_free(struct sctp_endpoint *ep)
166{
167 ep->base.dead = 1;
cfdeef32
VY
168
169 ep->base.sk->sk_state = SCTP_SS_CLOSED;
170
171 /* Unlink this endpoint, so we can't find it again! */
172 sctp_unhash_endpoint(ep);
173
1da177e4
LT
174 sctp_endpoint_put(ep);
175}
176
177/* Final destructor for endpoint. */
178static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
179{
180 SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
181
1da177e4 182 /* Free up the HMAC transform. */
1b489e11 183 crypto_free_hash(sctp_sk(ep->base.sk)->hmac);
1da177e4
LT
184
185 /* Cleanup. */
186 sctp_inq_free(&ep->base.inqueue);
187 sctp_bind_addr_free(&ep->base.bind_addr);
188
189 /* Remove and free the port */
190 if (sctp_sk(ep->base.sk)->bind_hash)
191 sctp_put_port(ep->base.sk);
192
193 /* Give up our hold on the sock. */
194 if (ep->base.sk)
195 sock_put(ep->base.sk);
196
197 /* Finally, free up our memory. */
198 if (ep->base.malloced) {
199 kfree(ep);
200 SCTP_DBG_OBJCNT_DEC(ep);
201 }
202}
203
204/* Hold a reference to an endpoint. */
205void sctp_endpoint_hold(struct sctp_endpoint *ep)
206{
207 atomic_inc(&ep->base.refcnt);
208}
209
210/* Release a reference to an endpoint and clean up if there are
211 * no more references.
212 */
213void sctp_endpoint_put(struct sctp_endpoint *ep)
214{
215 if (atomic_dec_and_test(&ep->base.refcnt))
216 sctp_endpoint_destroy(ep);
217}
218
219/* Is this the endpoint we are looking for? */
220struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
221 const union sctp_addr *laddr)
222{
223 struct sctp_endpoint *retval;
224
225 sctp_read_lock(&ep->base.addr_lock);
226 if (ep->base.bind_addr.port == laddr->v4.sin_port) {
227 if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
228 sctp_sk(ep->base.sk))) {
229 retval = ep;
230 goto out;
231 }
232 }
233
234 retval = NULL;
235
236out:
237 sctp_read_unlock(&ep->base.addr_lock);
238 return retval;
239}
240
241/* Find the association that goes with this chunk.
242 * We do a linear search of the associations for this endpoint.
243 * We return the matching transport address too.
244 */
245static struct sctp_association *__sctp_endpoint_lookup_assoc(
246 const struct sctp_endpoint *ep,
247 const union sctp_addr *paddr,
248 struct sctp_transport **transport)
249{
250 int rport;
251 struct sctp_association *asoc;
252 struct list_head *pos;
253
254 rport = paddr->v4.sin_port;
255
256 list_for_each(pos, &ep->asocs) {
257 asoc = list_entry(pos, struct sctp_association, asocs);
258 if (rport == asoc->peer.port) {
259 sctp_read_lock(&asoc->base.addr_lock);
260 *transport = sctp_assoc_lookup_paddr(asoc, paddr);
261 sctp_read_unlock(&asoc->base.addr_lock);
262
263 if (*transport)
264 return asoc;
265 }
266 }
267
268 *transport = NULL;
269 return NULL;
270}
271
272/* Lookup association on an endpoint based on a peer address. BH-safe. */
273struct sctp_association *sctp_endpoint_lookup_assoc(
274 const struct sctp_endpoint *ep,
275 const union sctp_addr *paddr,
276 struct sctp_transport **transport)
277{
278 struct sctp_association *asoc;
279
280 sctp_local_bh_disable();
281 asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
282 sctp_local_bh_enable();
283
284 return asoc;
285}
286
287/* Look for any peeled off association from the endpoint that matches the
288 * given peer address.
289 */
290int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
291 const union sctp_addr *paddr)
292{
293 struct list_head *pos;
294 struct sctp_sockaddr_entry *addr;
295 struct sctp_bind_addr *bp;
296
297 sctp_read_lock(&ep->base.addr_lock);
298 bp = &ep->base.bind_addr;
299 list_for_each(pos, &bp->address_list) {
300 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
301 if (sctp_has_association(&addr->a, paddr)) {
302 sctp_read_unlock(&ep->base.addr_lock);
303 return 1;
304 }
305 }
306 sctp_read_unlock(&ep->base.addr_lock);
307
308 return 0;
309}
310
311/* Do delayed input processing. This is scheduled by sctp_rcv().
312 * This may be called on BH or task time.
313 */
314static void sctp_endpoint_bh_rcv(struct sctp_endpoint *ep)
315{
316 struct sctp_association *asoc;
317 struct sock *sk;
318 struct sctp_transport *transport;
319 struct sctp_chunk *chunk;
320 struct sctp_inq *inqueue;
321 sctp_subtype_t subtype;
322 sctp_state_t state;
323 int error = 0;
324
325 if (ep->base.dead)
326 return;
327
328 asoc = NULL;
329 inqueue = &ep->base.inqueue;
330 sk = ep->base.sk;
331
332 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
333 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
334
335 /* We might have grown an association since last we
336 * looked, so try again.
337 *
338 * This happens when we've just processed our
339 * COOKIE-ECHO chunk.
340 */
341 if (NULL == chunk->asoc) {
342 asoc = sctp_endpoint_lookup_assoc(ep,
343 sctp_source(chunk),
344 &transport);
345 chunk->asoc = asoc;
346 chunk->transport = transport;
347 }
348
349 state = asoc ? asoc->state : SCTP_STATE_CLOSED;
350
351 /* Remember where the last DATA chunk came from so we
352 * know where to send the SACK.
353 */
354 if (asoc && sctp_chunk_is_data(chunk))
355 asoc->peer.last_data_from = chunk->transport;
356 else
357 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);
358
359 if (chunk->transport)
360 chunk->transport->last_time_heard = jiffies;
361
362 error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, state,
363 ep, asoc, chunk, GFP_ATOMIC);
364
365 if (error && chunk)
366 chunk->pdiscard = 1;
367
368 /* Check to see if the endpoint is freed in response to
369 * the incoming chunk. If so, get out of the while loop.
370 */
371 if (!sctp_sk(sk)->ep)
372 break;
373 }
374}