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1/* SCTP kernel 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 implementation
10 *
11 * This abstraction represents an SCTP endpoint.
12 *
13 * The SCTP implementation is free software;
14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
18 *
19 * The SCTP implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
29 *
30 * Please send any bug reports or fixes you make to the
31 * email address(es):
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 *
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
36 *
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * Jon Grimm <jgrimm@austin.ibm.com>
41 * Daisy Chang <daisyc@us.ibm.com>
42 * Dajiang Zhang <dajiang.zhang@nokia.com>
43 *
44 * Any bugs reported given to us we will try to fix... any fixes shared will
45 * be incorporated into the next SCTP release.
46 */
47
48#include <linux/types.h>
49#include <linux/slab.h>
50#include <linux/in.h>
51#include <linux/random.h> /* get_random_bytes() */
52#include <linux/crypto.h>
53#include <net/sock.h>
54#include <net/ipv6.h>
55#include <net/sctp/sctp.h>
56#include <net/sctp/sm.h>
57
58/* Forward declarations for internal helpers. */
59static void sctp_endpoint_bh_rcv(struct work_struct *work);
60
61/*
62 * Initialize the base fields of the endpoint structure.
63 */
64static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
65 struct sock *sk,
66 gfp_t gfp)
67{
68 struct sctp_hmac_algo_param *auth_hmacs = NULL;
69 struct sctp_chunks_param *auth_chunks = NULL;
70 struct sctp_shared_key *null_key;
71 int err;
72
73 ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp);
74 if (!ep->digest)
75 return NULL;
76
77 if (sctp_auth_enable) {
78 /* Allocate space for HMACS and CHUNKS authentication
79 * variables. There are arrays that we encode directly
80 * into parameters to make the rest of the operations easier.
81 */
82 auth_hmacs = kzalloc(sizeof(sctp_hmac_algo_param_t) +
83 sizeof(__u16) * SCTP_AUTH_NUM_HMACS, gfp);
84 if (!auth_hmacs)
85 goto nomem;
86
87 auth_chunks = kzalloc(sizeof(sctp_chunks_param_t) +
88 SCTP_NUM_CHUNK_TYPES, gfp);
89 if (!auth_chunks)
90 goto nomem;
91
92 /* Initialize the HMACS parameter.
93 * SCTP-AUTH: Section 3.3
94 * Every endpoint supporting SCTP chunk authentication MUST
95 * support the HMAC based on the SHA-1 algorithm.
96 */
97 auth_hmacs->param_hdr.type = SCTP_PARAM_HMAC_ALGO;
98 auth_hmacs->param_hdr.length =
99 htons(sizeof(sctp_paramhdr_t) + 2);
100 auth_hmacs->hmac_ids[0] = htons(SCTP_AUTH_HMAC_ID_SHA1);
101
102 /* Initialize the CHUNKS parameter */
103 auth_chunks->param_hdr.type = SCTP_PARAM_CHUNKS;
104 auth_chunks->param_hdr.length = htons(sizeof(sctp_paramhdr_t));
105
106 /* If the Add-IP functionality is enabled, we must
107 * authenticate, ASCONF and ASCONF-ACK chunks
108 */
109 if (sctp_addip_enable) {
110 auth_chunks->chunks[0] = SCTP_CID_ASCONF;
111 auth_chunks->chunks[1] = SCTP_CID_ASCONF_ACK;
112 auth_chunks->param_hdr.length =
113 htons(sizeof(sctp_paramhdr_t) + 2);
114 }
115 }
116
117 /* Initialize the base structure. */
118 /* What type of endpoint are we? */
119 ep->base.type = SCTP_EP_TYPE_SOCKET;
120
121 /* Initialize the basic object fields. */
122 atomic_set(&ep->base.refcnt, 1);
123 ep->base.dead = 0;
124 ep->base.malloced = 1;
125
126 /* Create an input queue. */
127 sctp_inq_init(&ep->base.inqueue);
128
129 /* Set its top-half handler */
130 sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);
131
132 /* Initialize the bind addr area */
133 sctp_bind_addr_init(&ep->base.bind_addr, 0);
134
135 /* Remember who we are attached to. */
136 ep->base.sk = sk;
137 sock_hold(ep->base.sk);
138
139 /* Create the lists of associations. */
140 INIT_LIST_HEAD(&ep->asocs);
141
142 /* Use SCTP specific send buffer space queues. */
143 ep->sndbuf_policy = sctp_sndbuf_policy;
144
145 sk->sk_data_ready = sctp_data_ready;
146 sk->sk_write_space = sctp_write_space;
147 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
148
149 /* Get the receive buffer policy for this endpoint */
150 ep->rcvbuf_policy = sctp_rcvbuf_policy;
151
152 /* Initialize the secret key used with cookie. */
153 get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
154 ep->last_key = ep->current_key = 0;
155 ep->key_changed_at = jiffies;
156
157 /* SCTP-AUTH extensions*/
158 INIT_LIST_HEAD(&ep->endpoint_shared_keys);
159 null_key = sctp_auth_shkey_create(0, GFP_KERNEL);
160 if (!null_key)
161 goto nomem;
162
163 list_add(&null_key->key_list, &ep->endpoint_shared_keys);
164
165 /* Allocate and initialize transorms arrays for suported HMACs. */
166 err = sctp_auth_init_hmacs(ep, gfp);
167 if (err)
168 goto nomem_hmacs;
169
170 /* Add the null key to the endpoint shared keys list and
171 * set the hmcas and chunks pointers.
172 */
173 ep->auth_hmacs_list = auth_hmacs;
174 ep->auth_chunk_list = auth_chunks;
175
176 return ep;
177
178nomem_hmacs:
179 sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
180nomem:
181 /* Free all allocations */
182 kfree(auth_hmacs);
183 kfree(auth_chunks);
184 kfree(ep->digest);
185 return NULL;
186
187}
188
189/* Create a sctp_endpoint with all that boring stuff initialized.
190 * Returns NULL if there isn't enough memory.
191 */
192struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp)
193{
194 struct sctp_endpoint *ep;
195
196 /* Build a local endpoint. */
197 ep = t_new(struct sctp_endpoint, gfp);
198 if (!ep)
199 goto fail;
200 if (!sctp_endpoint_init(ep, sk, gfp))
201 goto fail_init;
202 ep->base.malloced = 1;
203 SCTP_DBG_OBJCNT_INC(ep);
204 return ep;
205
206fail_init:
207 kfree(ep);
208fail:
209 return NULL;
210}
211
212/* Add an association to an endpoint. */
213void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
214 struct sctp_association *asoc)
215{
216 struct sock *sk = ep->base.sk;
217
218 /* If this is a temporary association, don't bother
219 * since we'll be removing it shortly and don't
220 * want anyone to find it anyway.
221 */
222 if (asoc->temp)
223 return;
224
225 /* Now just add it to our list of asocs */
226 list_add_tail(&asoc->asocs, &ep->asocs);
227
228 /* Increment the backlog value for a TCP-style listening socket. */
229 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
230 sk->sk_ack_backlog++;
231}
232
233/* Free the endpoint structure. Delay cleanup until
234 * all users have released their reference count on this structure.
235 */
236void sctp_endpoint_free(struct sctp_endpoint *ep)
237{
238 ep->base.dead = 1;
239
240 ep->base.sk->sk_state = SCTP_SS_CLOSED;
241
242 /* Unlink this endpoint, so we can't find it again! */
243 sctp_unhash_endpoint(ep);
244
245 sctp_endpoint_put(ep);
246}
247
248/* Final destructor for endpoint. */
249static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
250{
251 SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
252
253 /* Free up the HMAC transform. */
254 crypto_free_hash(sctp_sk(ep->base.sk)->hmac);
255
256 /* Free the digest buffer */
257 kfree(ep->digest);
258
259 /* SCTP-AUTH: Free up AUTH releated data such as shared keys
260 * chunks and hmacs arrays that were allocated
261 */
262 sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
263 kfree(ep->auth_hmacs_list);
264 kfree(ep->auth_chunk_list);
265
266 /* AUTH - Free any allocated HMAC transform containers */
267 sctp_auth_destroy_hmacs(ep->auth_hmacs);
268
269 /* Cleanup. */
270 sctp_inq_free(&ep->base.inqueue);
271 sctp_bind_addr_free(&ep->base.bind_addr);
272
273 /* Remove and free the port */
274 if (sctp_sk(ep->base.sk)->bind_hash)
275 sctp_put_port(ep->base.sk);
276
277 /* Give up our hold on the sock. */
278 if (ep->base.sk)
279 sock_put(ep->base.sk);
280
281 /* Finally, free up our memory. */
282 if (ep->base.malloced) {
283 kfree(ep);
284 SCTP_DBG_OBJCNT_DEC(ep);
285 }
286}
287
288/* Hold a reference to an endpoint. */
289void sctp_endpoint_hold(struct sctp_endpoint *ep)
290{
291 atomic_inc(&ep->base.refcnt);
292}
293
294/* Release a reference to an endpoint and clean up if there are
295 * no more references.
296 */
297void sctp_endpoint_put(struct sctp_endpoint *ep)
298{
299 if (atomic_dec_and_test(&ep->base.refcnt))
300 sctp_endpoint_destroy(ep);
301}
302
303/* Is this the endpoint we are looking for? */
304struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
305 const union sctp_addr *laddr)
306{
307 struct sctp_endpoint *retval = NULL;
308
309 if (htons(ep->base.bind_addr.port) == laddr->v4.sin_port) {
310 if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
311 sctp_sk(ep->base.sk)))
312 retval = ep;
313 }
314
315 return retval;
316}
317
318/* Find the association that goes with this chunk.
319 * We do a linear search of the associations for this endpoint.
320 * We return the matching transport address too.
321 */
322static struct sctp_association *__sctp_endpoint_lookup_assoc(
323 const struct sctp_endpoint *ep,
324 const union sctp_addr *paddr,
325 struct sctp_transport **transport)
326{
327 struct sctp_association *asoc = NULL;
328 struct sctp_association *tmp;
329 struct sctp_transport *t = NULL;
330 struct sctp_hashbucket *head;
331 struct sctp_ep_common *epb;
332 struct hlist_node *node;
333 int hash;
334 int rport;
335
336 *transport = NULL;
337
338 /* If the local port is not set, there can't be any associations
339 * on this endpoint.
340 */
341 if (!ep->base.bind_addr.port)
342 goto out;
343
344 rport = ntohs(paddr->v4.sin_port);
345
346 hash = sctp_assoc_hashfn(ep->base.bind_addr.port, rport);
347 head = &sctp_assoc_hashtable[hash];
348 read_lock(&head->lock);
349 sctp_for_each_hentry(epb, node, &head->chain) {
350 tmp = sctp_assoc(epb);
351 if (tmp->ep != ep || rport != tmp->peer.port)
352 continue;
353
354 t = sctp_assoc_lookup_paddr(tmp, paddr);
355 if (t) {
356 asoc = tmp;
357 *transport = t;
358 break;
359 }
360 }
361 read_unlock(&head->lock);
362out:
363 return asoc;
364}
365
366/* Lookup association on an endpoint based on a peer address. BH-safe. */
367struct sctp_association *sctp_endpoint_lookup_assoc(
368 const struct sctp_endpoint *ep,
369 const union sctp_addr *paddr,
370 struct sctp_transport **transport)
371{
372 struct sctp_association *asoc;
373
374 sctp_local_bh_disable();
375 asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
376 sctp_local_bh_enable();
377
378 return asoc;
379}
380
381/* Look for any peeled off association from the endpoint that matches the
382 * given peer address.
383 */
384int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
385 const union sctp_addr *paddr)
386{
387 struct sctp_sockaddr_entry *addr;
388 struct sctp_bind_addr *bp;
389
390 bp = &ep->base.bind_addr;
391 /* This function is called with the socket lock held,
392 * so the address_list can not change.
393 */
394 list_for_each_entry(addr, &bp->address_list, list) {
395 if (sctp_has_association(&addr->a, paddr))
396 return 1;
397 }
398
399 return 0;
400}
401
402/* Do delayed input processing. This is scheduled by sctp_rcv().
403 * This may be called on BH or task time.
404 */
405static void sctp_endpoint_bh_rcv(struct work_struct *work)
406{
407 struct sctp_endpoint *ep =
408 container_of(work, struct sctp_endpoint,
409 base.inqueue.immediate);
410 struct sctp_association *asoc;
411 struct sock *sk;
412 struct sctp_transport *transport;
413 struct sctp_chunk *chunk;
414 struct sctp_inq *inqueue;
415 sctp_subtype_t subtype;
416 sctp_state_t state;
417 int error = 0;
418 int first_time = 1; /* is this the first time through the looop */
419
420 if (ep->base.dead)
421 return;
422
423 asoc = NULL;
424 inqueue = &ep->base.inqueue;
425 sk = ep->base.sk;
426
427 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
428 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
429
430 /* If the first chunk in the packet is AUTH, do special
431 * processing specified in Section 6.3 of SCTP-AUTH spec
432 */
433 if (first_time && (subtype.chunk == SCTP_CID_AUTH)) {
434 struct sctp_chunkhdr *next_hdr;
435
436 next_hdr = sctp_inq_peek(inqueue);
437 if (!next_hdr)
438 goto normal;
439
440 /* If the next chunk is COOKIE-ECHO, skip the AUTH
441 * chunk while saving a pointer to it so we can do
442 * Authentication later (during cookie-echo
443 * processing).
444 */
445 if (next_hdr->type == SCTP_CID_COOKIE_ECHO) {
446 chunk->auth_chunk = skb_clone(chunk->skb,
447 GFP_ATOMIC);
448 chunk->auth = 1;
449 continue;
450 }
451 }
452normal:
453 /* We might have grown an association since last we
454 * looked, so try again.
455 *
456 * This happens when we've just processed our
457 * COOKIE-ECHO chunk.
458 */
459 if (NULL == chunk->asoc) {
460 asoc = sctp_endpoint_lookup_assoc(ep,
461 sctp_source(chunk),
462 &transport);
463 chunk->asoc = asoc;
464 chunk->transport = transport;
465 }
466
467 state = asoc ? asoc->state : SCTP_STATE_CLOSED;
468 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
469 continue;
470
471 /* Remember where the last DATA chunk came from so we
472 * know where to send the SACK.
473 */
474 if (asoc && sctp_chunk_is_data(chunk))
475 asoc->peer.last_data_from = chunk->transport;
476 else
477 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);
478
479 if (chunk->transport)
480 chunk->transport->last_time_heard = jiffies;
481
482 error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, state,
483 ep, asoc, chunk, GFP_ATOMIC);
484
485 if (error && chunk)
486 chunk->pdiscard = 1;
487
488 /* Check to see if the endpoint is freed in response to
489 * the incoming chunk. If so, get out of the while loop.
490 */
491 if (!sctp_sk(sk)->ep)
492 break;
493
494 if (first_time)
495 first_time = 0;
496 }
497}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* SCTP kernel implementation
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 International Business Machines, Corp.
6 * Copyright (c) 2001 Intel Corp.
7 * Copyright (c) 2001 Nokia, Inc.
8 * Copyright (c) 2001 La Monte H.P. Yarroll
9 *
10 * This file is part of the SCTP kernel implementation
11 *
12 * This abstraction represents an SCTP endpoint.
13 *
14 * Please send any bug reports or fixes you make to the
15 * email address(es):
16 * lksctp developers <linux-sctp@vger.kernel.org>
17 *
18 * Written or modified by:
19 * La Monte H.P. Yarroll <piggy@acm.org>
20 * Karl Knutson <karl@athena.chicago.il.us>
21 * Jon Grimm <jgrimm@austin.ibm.com>
22 * Daisy Chang <daisyc@us.ibm.com>
23 * Dajiang Zhang <dajiang.zhang@nokia.com>
24 */
25
26#include <linux/types.h>
27#include <linux/slab.h>
28#include <linux/in.h>
29#include <linux/random.h> /* get_random_bytes() */
30#include <net/sock.h>
31#include <net/ipv6.h>
32#include <net/sctp/sctp.h>
33#include <net/sctp/sm.h>
34
35/* Forward declarations for internal helpers. */
36static void sctp_endpoint_bh_rcv(struct work_struct *work);
37
38/*
39 * Initialize the base fields of the endpoint structure.
40 */
41static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
42 struct sock *sk,
43 gfp_t gfp)
44{
45 struct net *net = sock_net(sk);
46 struct sctp_shared_key *null_key;
47
48 ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp);
49 if (!ep->digest)
50 return NULL;
51
52 ep->asconf_enable = net->sctp.addip_enable;
53 ep->auth_enable = net->sctp.auth_enable;
54 if (ep->auth_enable) {
55 if (sctp_auth_init(ep, gfp))
56 goto nomem;
57 if (ep->asconf_enable) {
58 sctp_auth_ep_add_chunkid(ep, SCTP_CID_ASCONF);
59 sctp_auth_ep_add_chunkid(ep, SCTP_CID_ASCONF_ACK);
60 }
61 }
62
63 /* Initialize the base structure. */
64 /* What type of endpoint are we? */
65 ep->base.type = SCTP_EP_TYPE_SOCKET;
66
67 /* Initialize the basic object fields. */
68 refcount_set(&ep->base.refcnt, 1);
69 ep->base.dead = false;
70
71 /* Create an input queue. */
72 sctp_inq_init(&ep->base.inqueue);
73
74 /* Set its top-half handler */
75 sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);
76
77 /* Initialize the bind addr area */
78 sctp_bind_addr_init(&ep->base.bind_addr, 0);
79
80 /* Create the lists of associations. */
81 INIT_LIST_HEAD(&ep->asocs);
82
83 /* Use SCTP specific send buffer space queues. */
84 ep->sndbuf_policy = net->sctp.sndbuf_policy;
85
86 sk->sk_data_ready = sctp_data_ready;
87 sk->sk_write_space = sctp_write_space;
88 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
89
90 /* Get the receive buffer policy for this endpoint */
91 ep->rcvbuf_policy = net->sctp.rcvbuf_policy;
92
93 /* Initialize the secret key used with cookie. */
94 get_random_bytes(ep->secret_key, sizeof(ep->secret_key));
95
96 /* SCTP-AUTH extensions*/
97 INIT_LIST_HEAD(&ep->endpoint_shared_keys);
98 null_key = sctp_auth_shkey_create(0, gfp);
99 if (!null_key)
100 goto nomem_shkey;
101
102 list_add(&null_key->key_list, &ep->endpoint_shared_keys);
103
104 /* Add the null key to the endpoint shared keys list and
105 * set the hmcas and chunks pointers.
106 */
107 ep->prsctp_enable = net->sctp.prsctp_enable;
108 ep->reconf_enable = net->sctp.reconf_enable;
109 ep->ecn_enable = net->sctp.ecn_enable;
110
111 /* Remember who we are attached to. */
112 ep->base.sk = sk;
113 ep->base.net = sock_net(sk);
114 sock_hold(ep->base.sk);
115
116 return ep;
117
118nomem_shkey:
119 sctp_auth_free(ep);
120nomem:
121 kfree(ep->digest);
122 return NULL;
123
124}
125
126/* Create a sctp_endpoint with all that boring stuff initialized.
127 * Returns NULL if there isn't enough memory.
128 */
129struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp)
130{
131 struct sctp_endpoint *ep;
132
133 /* Build a local endpoint. */
134 ep = kzalloc(sizeof(*ep), gfp);
135 if (!ep)
136 goto fail;
137
138 if (!sctp_endpoint_init(ep, sk, gfp))
139 goto fail_init;
140
141 SCTP_DBG_OBJCNT_INC(ep);
142 return ep;
143
144fail_init:
145 kfree(ep);
146fail:
147 return NULL;
148}
149
150/* Add an association to an endpoint. */
151void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
152 struct sctp_association *asoc)
153{
154 struct sock *sk = ep->base.sk;
155
156 /* If this is a temporary association, don't bother
157 * since we'll be removing it shortly and don't
158 * want anyone to find it anyway.
159 */
160 if (asoc->temp)
161 return;
162
163 /* Now just add it to our list of asocs */
164 list_add_tail(&asoc->asocs, &ep->asocs);
165
166 /* Increment the backlog value for a TCP-style listening socket. */
167 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
168 sk_acceptq_added(sk);
169}
170
171/* Free the endpoint structure. Delay cleanup until
172 * all users have released their reference count on this structure.
173 */
174void sctp_endpoint_free(struct sctp_endpoint *ep)
175{
176 ep->base.dead = true;
177
178 inet_sk_set_state(ep->base.sk, SCTP_SS_CLOSED);
179
180 /* Unlink this endpoint, so we can't find it again! */
181 sctp_unhash_endpoint(ep);
182
183 sctp_endpoint_put(ep);
184}
185
186/* Final destructor for endpoint. */
187static void sctp_endpoint_destroy_rcu(struct rcu_head *head)
188{
189 struct sctp_endpoint *ep = container_of(head, struct sctp_endpoint, rcu);
190 struct sock *sk = ep->base.sk;
191
192 sctp_sk(sk)->ep = NULL;
193 sock_put(sk);
194
195 kfree(ep);
196 SCTP_DBG_OBJCNT_DEC(ep);
197}
198
199static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
200{
201 struct sock *sk;
202
203 if (unlikely(!ep->base.dead)) {
204 WARN(1, "Attempt to destroy undead endpoint %p!\n", ep);
205 return;
206 }
207
208 /* Free the digest buffer */
209 kfree(ep->digest);
210
211 /* SCTP-AUTH: Free up AUTH releated data such as shared keys
212 * chunks and hmacs arrays that were allocated
213 */
214 sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
215 sctp_auth_free(ep);
216
217 /* Cleanup. */
218 sctp_inq_free(&ep->base.inqueue);
219 sctp_bind_addr_free(&ep->base.bind_addr);
220
221 memset(ep->secret_key, 0, sizeof(ep->secret_key));
222
223 sk = ep->base.sk;
224 /* Remove and free the port */
225 if (sctp_sk(sk)->bind_hash)
226 sctp_put_port(sk);
227
228 call_rcu(&ep->rcu, sctp_endpoint_destroy_rcu);
229}
230
231/* Hold a reference to an endpoint. */
232int sctp_endpoint_hold(struct sctp_endpoint *ep)
233{
234 return refcount_inc_not_zero(&ep->base.refcnt);
235}
236
237/* Release a reference to an endpoint and clean up if there are
238 * no more references.
239 */
240void sctp_endpoint_put(struct sctp_endpoint *ep)
241{
242 if (refcount_dec_and_test(&ep->base.refcnt))
243 sctp_endpoint_destroy(ep);
244}
245
246/* Is this the endpoint we are looking for? */
247struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
248 struct net *net,
249 const union sctp_addr *laddr,
250 int dif, int sdif)
251{
252 int bound_dev_if = READ_ONCE(ep->base.sk->sk_bound_dev_if);
253 struct sctp_endpoint *retval = NULL;
254
255 if (net_eq(ep->base.net, net) &&
256 sctp_sk_bound_dev_eq(net, bound_dev_if, dif, sdif) &&
257 (htons(ep->base.bind_addr.port) == laddr->v4.sin_port)) {
258 if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
259 sctp_sk(ep->base.sk)))
260 retval = ep;
261 }
262
263 return retval;
264}
265
266/* Find the association that goes with this chunk.
267 * We lookup the transport from hashtable at first, then get association
268 * through t->assoc.
269 */
270struct sctp_association *sctp_endpoint_lookup_assoc(
271 const struct sctp_endpoint *ep,
272 const union sctp_addr *paddr,
273 struct sctp_transport **transport)
274{
275 struct sctp_association *asoc = NULL;
276 struct sctp_transport *t;
277
278 *transport = NULL;
279
280 /* If the local port is not set, there can't be any associations
281 * on this endpoint.
282 */
283 if (!ep->base.bind_addr.port)
284 return NULL;
285
286 rcu_read_lock();
287 t = sctp_epaddr_lookup_transport(ep, paddr);
288 if (!t)
289 goto out;
290
291 *transport = t;
292 asoc = t->asoc;
293out:
294 rcu_read_unlock();
295 return asoc;
296}
297
298/* Look for any peeled off association from the endpoint that matches the
299 * given peer address.
300 */
301bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
302 const union sctp_addr *paddr)
303{
304 int bound_dev_if = READ_ONCE(ep->base.sk->sk_bound_dev_if);
305 struct sctp_sockaddr_entry *addr;
306 struct net *net = ep->base.net;
307 struct sctp_bind_addr *bp;
308
309 bp = &ep->base.bind_addr;
310 /* This function is called with the socket lock held,
311 * so the address_list can not change.
312 */
313 list_for_each_entry(addr, &bp->address_list, list) {
314 if (sctp_has_association(net, &addr->a, paddr,
315 bound_dev_if, bound_dev_if))
316 return true;
317 }
318
319 return false;
320}
321
322/* Do delayed input processing. This is scheduled by sctp_rcv().
323 * This may be called on BH or task time.
324 */
325static void sctp_endpoint_bh_rcv(struct work_struct *work)
326{
327 struct sctp_endpoint *ep =
328 container_of(work, struct sctp_endpoint,
329 base.inqueue.immediate);
330 struct sctp_association *asoc;
331 struct sock *sk;
332 struct net *net;
333 struct sctp_transport *transport;
334 struct sctp_chunk *chunk;
335 struct sctp_inq *inqueue;
336 union sctp_subtype subtype;
337 enum sctp_state state;
338 int error = 0;
339 int first_time = 1; /* is this the first time through the loop */
340
341 if (ep->base.dead)
342 return;
343
344 asoc = NULL;
345 inqueue = &ep->base.inqueue;
346 sk = ep->base.sk;
347 net = sock_net(sk);
348
349 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
350 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
351
352 /* If the first chunk in the packet is AUTH, do special
353 * processing specified in Section 6.3 of SCTP-AUTH spec
354 */
355 if (first_time && (subtype.chunk == SCTP_CID_AUTH)) {
356 struct sctp_chunkhdr *next_hdr;
357
358 next_hdr = sctp_inq_peek(inqueue);
359 if (!next_hdr)
360 goto normal;
361
362 /* If the next chunk is COOKIE-ECHO, skip the AUTH
363 * chunk while saving a pointer to it so we can do
364 * Authentication later (during cookie-echo
365 * processing).
366 */
367 if (next_hdr->type == SCTP_CID_COOKIE_ECHO) {
368 chunk->auth_chunk = skb_clone(chunk->skb,
369 GFP_ATOMIC);
370 chunk->auth = 1;
371 continue;
372 }
373 }
374normal:
375 /* We might have grown an association since last we
376 * looked, so try again.
377 *
378 * This happens when we've just processed our
379 * COOKIE-ECHO chunk.
380 */
381 if (NULL == chunk->asoc) {
382 asoc = sctp_endpoint_lookup_assoc(ep,
383 sctp_source(chunk),
384 &transport);
385 chunk->asoc = asoc;
386 chunk->transport = transport;
387 }
388
389 state = asoc ? asoc->state : SCTP_STATE_CLOSED;
390 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
391 continue;
392
393 /* Remember where the last DATA chunk came from so we
394 * know where to send the SACK.
395 */
396 if (asoc && sctp_chunk_is_data(chunk))
397 asoc->peer.last_data_from = chunk->transport;
398 else {
399 SCTP_INC_STATS(ep->base.net, SCTP_MIB_INCTRLCHUNKS);
400 if (asoc)
401 asoc->stats.ictrlchunks++;
402 }
403
404 if (chunk->transport)
405 chunk->transport->last_time_heard = ktime_get();
406
407 error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype, state,
408 ep, asoc, chunk, GFP_ATOMIC);
409
410 if (error && chunk)
411 chunk->pdiscard = 1;
412
413 /* Check to see if the endpoint is freed in response to
414 * the incoming chunk. If so, get out of the while loop.
415 */
416 if (!sctp_sk(sk)->ep)
417 break;
418
419 if (first_time)
420 first_time = 0;
421 }
422}