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
9 * This file is part of the SCTP kernel reference Implementation
11 * This abstraction represents an SCTP endpoint.
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.
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)
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.
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.
34 * Please send any bug reports or fixes you make to the
36 * lksctp developers <lksctp-developers@lists.sourceforge.net>
38 * Or submit a bug report through the following website:
39 * http://www.sf.net/projects/lksctp
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>
48 * Any bugs reported given to us we will try to fix... any fixes shared will
49 * be incorporated into the next SCTP release.
52 #include <linux/types.h>
53 #include <linux/sched.h>
54 #include <linux/slab.h>
56 #include <linux/random.h> /* get_random_bytes() */
57 #include <linux/crypto.h>
60 #include <net/sctp/sctp.h>
61 #include <net/sctp/sm.h>
63 /* Forward declarations for internal helpers. */
64 static void sctp_endpoint_bh_rcv(struct work_struct *work);
67 * Initialize the base fields of the endpoint structure.
69 static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
73 memset(ep, 0, sizeof(struct sctp_endpoint));
75 /* Initialize the base structure. */
76 /* What type of endpoint are we? */
77 ep->base.type = SCTP_EP_TYPE_SOCKET;
79 /* Initialize the basic object fields. */
80 atomic_set(&ep->base.refcnt, 1);
82 ep->base.malloced = 1;
84 /* Create an input queue. */
85 sctp_inq_init(&ep->base.inqueue);
87 /* Set its top-half handler */
88 sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);
90 /* Initialize the bind addr area */
91 sctp_bind_addr_init(&ep->base.bind_addr, 0);
92 rwlock_init(&ep->base.addr_lock);
94 /* Remember who we are attached to. */
96 sock_hold(ep->base.sk);
98 /* Create the lists of associations. */
99 INIT_LIST_HEAD(&ep->asocs);
101 /* Use SCTP specific send buffer space queues. */
102 ep->sndbuf_policy = sctp_sndbuf_policy;
103 sk->sk_write_space = sctp_write_space;
104 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
106 /* Get the receive buffer policy for this endpoint */
107 ep->rcvbuf_policy = sctp_rcvbuf_policy;
109 /* Initialize the secret key used with cookie. */
110 get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
111 ep->last_key = ep->current_key = 0;
112 ep->key_changed_at = jiffies;
117 /* Create a sctp_endpoint with all that boring stuff initialized.
118 * Returns NULL if there isn't enough memory.
120 struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp)
122 struct sctp_endpoint *ep;
124 /* Build a local endpoint. */
125 ep = t_new(struct sctp_endpoint, gfp);
128 if (!sctp_endpoint_init(ep, sk, gfp))
130 ep->base.malloced = 1;
131 SCTP_DBG_OBJCNT_INC(ep);
140 /* Add an association to an endpoint. */
141 void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
142 struct sctp_association *asoc)
144 struct sock *sk = ep->base.sk;
146 /* If this is a temporary association, don't bother
147 * since we'll be removing it shortly and don't
148 * want anyone to find it anyway.
153 /* Now just add it to our list of asocs */
154 list_add_tail(&asoc->asocs, &ep->asocs);
156 /* Increment the backlog value for a TCP-style listening socket. */
157 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
158 sk->sk_ack_backlog++;
161 /* Free the endpoint structure. Delay cleanup until
162 * all users have released their reference count on this structure.
164 void sctp_endpoint_free(struct sctp_endpoint *ep)
168 ep->base.sk->sk_state = SCTP_SS_CLOSED;
170 /* Unlink this endpoint, so we can't find it again! */
171 sctp_unhash_endpoint(ep);
173 sctp_endpoint_put(ep);
176 /* Final destructor for endpoint. */
177 static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
179 SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
181 /* Free up the HMAC transform. */
182 crypto_free_hash(sctp_sk(ep->base.sk)->hmac);
185 sctp_inq_free(&ep->base.inqueue);
186 sctp_bind_addr_free(&ep->base.bind_addr);
188 /* Remove and free the port */
189 if (sctp_sk(ep->base.sk)->bind_hash)
190 sctp_put_port(ep->base.sk);
192 /* Give up our hold on the sock. */
194 sock_put(ep->base.sk);
196 /* Finally, free up our memory. */
197 if (ep->base.malloced) {
199 SCTP_DBG_OBJCNT_DEC(ep);
203 /* Hold a reference to an endpoint. */
204 void sctp_endpoint_hold(struct sctp_endpoint *ep)
206 atomic_inc(&ep->base.refcnt);
209 /* Release a reference to an endpoint and clean up if there are
210 * no more references.
212 void sctp_endpoint_put(struct sctp_endpoint *ep)
214 if (atomic_dec_and_test(&ep->base.refcnt))
215 sctp_endpoint_destroy(ep);
218 /* Is this the endpoint we are looking for? */
219 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
220 const union sctp_addr *laddr)
222 struct sctp_endpoint *retval;
224 sctp_read_lock(&ep->base.addr_lock);
225 if (ep->base.bind_addr.port == laddr->v4.sin_port) {
226 if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
227 sctp_sk(ep->base.sk))) {
236 sctp_read_unlock(&ep->base.addr_lock);
240 /* Find the association that goes with this chunk.
241 * We do a linear search of the associations for this endpoint.
242 * We return the matching transport address too.
244 static struct sctp_association *__sctp_endpoint_lookup_assoc(
245 const struct sctp_endpoint *ep,
246 const union sctp_addr *paddr,
247 struct sctp_transport **transport)
250 struct sctp_association *asoc;
251 struct list_head *pos;
253 rport = paddr->v4.sin_port;
255 list_for_each(pos, &ep->asocs) {
256 asoc = list_entry(pos, struct sctp_association, asocs);
257 if (rport == asoc->peer.port) {
258 sctp_read_lock(&asoc->base.addr_lock);
259 *transport = sctp_assoc_lookup_paddr(asoc, paddr);
260 sctp_read_unlock(&asoc->base.addr_lock);
271 /* Lookup association on an endpoint based on a peer address. BH-safe. */
272 struct sctp_association *sctp_endpoint_lookup_assoc(
273 const struct sctp_endpoint *ep,
274 const union sctp_addr *paddr,
275 struct sctp_transport **transport)
277 struct sctp_association *asoc;
279 sctp_local_bh_disable();
280 asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
281 sctp_local_bh_enable();
286 /* Look for any peeled off association from the endpoint that matches the
287 * given peer address.
289 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
290 const union sctp_addr *paddr)
292 struct list_head *pos;
293 struct sctp_sockaddr_entry *addr;
294 struct sctp_bind_addr *bp;
296 sctp_read_lock(&ep->base.addr_lock);
297 bp = &ep->base.bind_addr;
298 list_for_each(pos, &bp->address_list) {
299 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
300 if (sctp_has_association(&addr->a, paddr)) {
301 sctp_read_unlock(&ep->base.addr_lock);
305 sctp_read_unlock(&ep->base.addr_lock);
310 /* Do delayed input processing. This is scheduled by sctp_rcv().
311 * This may be called on BH or task time.
313 static void sctp_endpoint_bh_rcv(struct work_struct *work)
315 struct sctp_endpoint *ep =
316 container_of(work, struct sctp_endpoint,
317 base.inqueue.immediate);
318 struct sctp_association *asoc;
320 struct sctp_transport *transport;
321 struct sctp_chunk *chunk;
322 struct sctp_inq *inqueue;
323 sctp_subtype_t subtype;
331 inqueue = &ep->base.inqueue;
334 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
335 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
337 /* We might have grown an association since last we
338 * looked, so try again.
340 * This happens when we've just processed our
343 if (NULL == chunk->asoc) {
344 asoc = sctp_endpoint_lookup_assoc(ep,
348 chunk->transport = transport;
351 state = asoc ? asoc->state : SCTP_STATE_CLOSED;
353 /* Remember where the last DATA chunk came from so we
354 * know where to send the SACK.
356 if (asoc && sctp_chunk_is_data(chunk))
357 asoc->peer.last_data_from = chunk->transport;
359 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);
361 if (chunk->transport)
362 chunk->transport->last_time_heard = jiffies;
364 error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, state,
365 ep, asoc, chunk, GFP_ATOMIC);
370 /* Check to see if the endpoint is freed in response to
371 * the incoming chunk. If so, get out of the while loop.
373 if (!sctp_sk(sk)->ep)