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/slab.h>
55 #include <linux/random.h> /* get_random_bytes() */
56 #include <linux/crypto.h>
59 #include <net/sctp/sctp.h>
60 #include <net/sctp/sm.h>
62 /* Forward declarations for internal helpers. */
63 static void sctp_endpoint_bh_rcv(struct work_struct *work);
66 * Initialize the base fields of the endpoint structure.
68 static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
72 memset(ep, 0, sizeof(struct sctp_endpoint));
74 ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp);
78 /* Initialize the base structure. */
79 /* What type of endpoint are we? */
80 ep->base.type = SCTP_EP_TYPE_SOCKET;
82 /* Initialize the basic object fields. */
83 atomic_set(&ep->base.refcnt, 1);
85 ep->base.malloced = 1;
87 /* Create an input queue. */
88 sctp_inq_init(&ep->base.inqueue);
90 /* Set its top-half handler */
91 sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);
93 /* Initialize the bind addr area */
94 sctp_bind_addr_init(&ep->base.bind_addr, 0);
96 /* Remember who we are attached to. */
98 sock_hold(ep->base.sk);
100 /* Create the lists of associations. */
101 INIT_LIST_HEAD(&ep->asocs);
103 /* Use SCTP specific send buffer space queues. */
104 ep->sndbuf_policy = sctp_sndbuf_policy;
105 sk->sk_write_space = sctp_write_space;
106 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
108 /* Get the receive buffer policy for this endpoint */
109 ep->rcvbuf_policy = sctp_rcvbuf_policy;
111 /* Initialize the secret key used with cookie. */
112 get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
113 ep->last_key = ep->current_key = 0;
114 ep->key_changed_at = jiffies;
119 /* Create a sctp_endpoint with all that boring stuff initialized.
120 * Returns NULL if there isn't enough memory.
122 struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp)
124 struct sctp_endpoint *ep;
126 /* Build a local endpoint. */
127 ep = t_new(struct sctp_endpoint, gfp);
130 if (!sctp_endpoint_init(ep, sk, gfp))
132 ep->base.malloced = 1;
133 SCTP_DBG_OBJCNT_INC(ep);
142 /* Add an association to an endpoint. */
143 void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
144 struct sctp_association *asoc)
146 struct sock *sk = ep->base.sk;
148 /* If this is a temporary association, don't bother
149 * since we'll be removing it shortly and don't
150 * want anyone to find it anyway.
155 /* Now just add it to our list of asocs */
156 list_add_tail(&asoc->asocs, &ep->asocs);
158 /* Increment the backlog value for a TCP-style listening socket. */
159 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
160 sk->sk_ack_backlog++;
163 /* Free the endpoint structure. Delay cleanup until
164 * all users have released their reference count on this structure.
166 void sctp_endpoint_free(struct sctp_endpoint *ep)
170 ep->base.sk->sk_state = SCTP_SS_CLOSED;
172 /* Unlink this endpoint, so we can't find it again! */
173 sctp_unhash_endpoint(ep);
175 sctp_endpoint_put(ep);
178 /* Final destructor for endpoint. */
179 static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
181 SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
183 /* Free up the HMAC transform. */
184 crypto_free_hash(sctp_sk(ep->base.sk)->hmac);
186 /* Free the digest buffer */
190 sctp_inq_free(&ep->base.inqueue);
191 sctp_bind_addr_free(&ep->base.bind_addr);
193 /* Remove and free the port */
194 if (sctp_sk(ep->base.sk)->bind_hash)
195 sctp_put_port(ep->base.sk);
197 /* Give up our hold on the sock. */
199 sock_put(ep->base.sk);
201 /* Finally, free up our memory. */
202 if (ep->base.malloced) {
204 SCTP_DBG_OBJCNT_DEC(ep);
208 /* Hold a reference to an endpoint. */
209 void sctp_endpoint_hold(struct sctp_endpoint *ep)
211 atomic_inc(&ep->base.refcnt);
214 /* Release a reference to an endpoint and clean up if there are
215 * no more references.
217 void sctp_endpoint_put(struct sctp_endpoint *ep)
219 if (atomic_dec_and_test(&ep->base.refcnt))
220 sctp_endpoint_destroy(ep);
223 /* Is this the endpoint we are looking for? */
224 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
225 const union sctp_addr *laddr)
227 struct sctp_endpoint *retval = NULL;
229 if (htons(ep->base.bind_addr.port) == laddr->v4.sin_port) {
230 if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
231 sctp_sk(ep->base.sk)))
238 /* Find the association that goes with this chunk.
239 * We do a linear search of the associations for this endpoint.
240 * We return the matching transport address too.
242 static struct sctp_association *__sctp_endpoint_lookup_assoc(
243 const struct sctp_endpoint *ep,
244 const union sctp_addr *paddr,
245 struct sctp_transport **transport)
248 struct sctp_association *asoc;
249 struct list_head *pos;
251 rport = ntohs(paddr->v4.sin_port);
253 list_for_each(pos, &ep->asocs) {
254 asoc = list_entry(pos, struct sctp_association, asocs);
255 if (rport == asoc->peer.port) {
256 *transport = sctp_assoc_lookup_paddr(asoc, paddr);
267 /* Lookup association on an endpoint based on a peer address. BH-safe. */
268 struct sctp_association *sctp_endpoint_lookup_assoc(
269 const struct sctp_endpoint *ep,
270 const union sctp_addr *paddr,
271 struct sctp_transport **transport)
273 struct sctp_association *asoc;
275 sctp_local_bh_disable();
276 asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
277 sctp_local_bh_enable();
282 /* Look for any peeled off association from the endpoint that matches the
283 * given peer address.
285 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
286 const union sctp_addr *paddr)
288 struct sctp_sockaddr_entry *addr;
289 struct sctp_bind_addr *bp;
291 bp = &ep->base.bind_addr;
292 /* This function is called with the socket lock held,
293 * so the address_list can not change.
295 list_for_each_entry(addr, &bp->address_list, list) {
296 if (sctp_has_association(&addr->a, paddr))
303 /* Do delayed input processing. This is scheduled by sctp_rcv().
304 * This may be called on BH or task time.
306 static void sctp_endpoint_bh_rcv(struct work_struct *work)
308 struct sctp_endpoint *ep =
309 container_of(work, struct sctp_endpoint,
310 base.inqueue.immediate);
311 struct sctp_association *asoc;
313 struct sctp_transport *transport;
314 struct sctp_chunk *chunk;
315 struct sctp_inq *inqueue;
316 sctp_subtype_t subtype;
324 inqueue = &ep->base.inqueue;
327 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
328 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
330 /* We might have grown an association since last we
331 * looked, so try again.
333 * This happens when we've just processed our
336 if (NULL == chunk->asoc) {
337 asoc = sctp_endpoint_lookup_assoc(ep,
341 chunk->transport = transport;
344 state = asoc ? asoc->state : SCTP_STATE_CLOSED;
346 /* Remember where the last DATA chunk came from so we
347 * know where to send the SACK.
349 if (asoc && sctp_chunk_is_data(chunk))
350 asoc->peer.last_data_from = chunk->transport;
352 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);
354 if (chunk->transport)
355 chunk->transport->last_time_heard = jiffies;
357 error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, state,
358 ep, asoc, chunk, GFP_ATOMIC);
363 /* Check to see if the endpoint is freed in response to
364 * the incoming chunk. If so, get out of the while loop.
366 if (!sctp_sk(sk)->ep)