[mirror_ubuntu-artful-kernel.git] / net / sctp / endpointola.c

/* SCTP kernel implementation
 * Copyright (c) 1999-2000 Cisco, Inc.
 * Copyright (c) 1999-2001 Motorola, Inc.
 * Copyright (c) 2001-2002 International Business Machines, Corp.
 * Copyright (c) 2001 Intel Corp.
 * Copyright (c) 2001 Nokia, Inc.
 * Copyright (c) 2001 La Monte H.P. Yarroll
 *
 * This file is part of the SCTP kernel implementation
 *
 * This abstraction represents an SCTP endpoint.
 *
 * The SCTP implementation is free software;
 * you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * The SCTP implementation is distributed in the hope that it
 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 *                 ************************
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU CC; see the file COPYING.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
 *    lksctp developers <linux-sctp@vger.kernel.org>
 *
 * Written or modified by:
 *    La Monte H.P. Yarroll <piggy@acm.org>
 *    Karl Knutson <karl@athena.chicago.il.us>
 *    Jon Grimm <jgrimm@austin.ibm.com>
 *    Daisy Chang <daisyc@us.ibm.com>
 *    Dajiang Zhang <dajiang.zhang@nokia.com>
 */

#include <linux/types.h>
#include <linux/slab.h>
#include <linux/in.h>
#include <linux/random.h>	/* get_random_bytes() */
#include <net/sock.h>
#include <net/ipv6.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>

/* Forward declarations for internal helpers. */
static void sctp_endpoint_bh_rcv(struct work_struct *work);

/*
 * Initialize the base fields of the endpoint structure.
 */
static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
						struct sock *sk,
						gfp_t gfp)
{
	struct net *net = sock_net(sk);
	struct sctp_hmac_algo_param *auth_hmacs = NULL;
	struct sctp_chunks_param *auth_chunks = NULL;
	struct sctp_shared_key *null_key;
	int err;

	ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp);
	if (!ep->digest)
		return NULL;

	ep->auth_enable = net->sctp.auth_enable;
	if (ep->auth_enable) {
		/* Allocate space for HMACS and CHUNKS authentication
		 * variables.  There are arrays that we encode directly
		 * into parameters to make the rest of the operations easier.
		 */
		auth_hmacs = kzalloc(sizeof(sctp_hmac_algo_param_t) +
				sizeof(__u16) * SCTP_AUTH_NUM_HMACS, gfp);
		if (!auth_hmacs)
			goto nomem;

		auth_chunks = kzalloc(sizeof(sctp_chunks_param_t) +
					SCTP_NUM_CHUNK_TYPES, gfp);
		if (!auth_chunks)
			goto nomem;

		/* Initialize the HMACS parameter.
		 * SCTP-AUTH: Section 3.3
		 *    Every endpoint supporting SCTP chunk authentication MUST
		 *    support the HMAC based on the SHA-1 algorithm.
		 */
		auth_hmacs->param_hdr.type = SCTP_PARAM_HMAC_ALGO;
		auth_hmacs->param_hdr.length =
					htons(sizeof(sctp_paramhdr_t) + 2);
		auth_hmacs->hmac_ids[0] = htons(SCTP_AUTH_HMAC_ID_SHA1);

		/* Initialize the CHUNKS parameter */
		auth_chunks->param_hdr.type = SCTP_PARAM_CHUNKS;
		auth_chunks->param_hdr.length = htons(sizeof(sctp_paramhdr_t));

		/* If the Add-IP functionality is enabled, we must
		 * authenticate, ASCONF and ASCONF-ACK chunks
		 */
		if (net->sctp.addip_enable) {
			auth_chunks->chunks[0] = SCTP_CID_ASCONF;
			auth_chunks->chunks[1] = SCTP_CID_ASCONF_ACK;
			auth_chunks->param_hdr.length =
					htons(sizeof(sctp_paramhdr_t) + 2);
		}
	}

	/* Initialize the base structure. */
	/* What type of endpoint are we?  */
	ep->base.type = SCTP_EP_TYPE_SOCKET;

	/* Initialize the basic object fields. */
	atomic_set(&ep->base.refcnt, 1);
	ep->base.dead = false;

	/* Create an input queue.  */
	sctp_inq_init(&ep->base.inqueue);

	/* Set its top-half handler */
	sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);

	/* Initialize the bind addr area */
	sctp_bind_addr_init(&ep->base.bind_addr, 0);

	/* Remember who we are attached to.  */
	ep->base.sk = sk;
	sock_hold(ep->base.sk);

	/* Create the lists of associations.  */
	INIT_LIST_HEAD(&ep->asocs);

	/* Use SCTP specific send buffer space queues.  */
	ep->sndbuf_policy = net->sctp.sndbuf_policy;

	sk->sk_data_ready = sctp_data_ready;
	sk->sk_write_space = sctp_write_space;
	sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);

	/* Get the receive buffer policy for this endpoint */
	ep->rcvbuf_policy = net->sctp.rcvbuf_policy;

	/* Initialize the secret key used with cookie. */
	get_random_bytes(ep->secret_key, sizeof(ep->secret_key));

	/* SCTP-AUTH extensions*/
	INIT_LIST_HEAD(&ep->endpoint_shared_keys);
	null_key = sctp_auth_shkey_create(0, gfp);
	if (!null_key)
		goto nomem;

	list_add(&null_key->key_list, &ep->endpoint_shared_keys);

	/* Allocate and initialize transorms arrays for supported HMACs. */
	err = sctp_auth_init_hmacs(ep, gfp);
	if (err)
		goto nomem_hmacs;

	/* Add the null key to the endpoint shared keys list and
	 * set the hmcas and chunks pointers.
	 */
	ep->auth_hmacs_list = auth_hmacs;
	ep->auth_chunk_list = auth_chunks;
	ep->prsctp_enable = net->sctp.prsctp_enable;

	return ep;

nomem_hmacs:
	sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
nomem:
	/* Free all allocations */
	kfree(auth_hmacs);
	kfree(auth_chunks);
	kfree(ep->digest);
	return NULL;

}

/* Create a sctp_endpoint with all that boring stuff initialized.
 * Returns NULL if there isn't enough memory.
 */
struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp)
{
	struct sctp_endpoint *ep;

	/* Build a local endpoint. */
	ep = kzalloc(sizeof(*ep), gfp);
	if (!ep)
		goto fail;

	if (!sctp_endpoint_init(ep, sk, gfp))
		goto fail_init;

	SCTP_DBG_OBJCNT_INC(ep);
	return ep;

fail_init:
	kfree(ep);
fail:
	return NULL;
}

/* Add an association to an endpoint.  */
void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
			    struct sctp_association *asoc)
{
	struct sock *sk = ep->base.sk;

	/* If this is a temporary association, don't bother
	 * since we'll be removing it shortly and don't
	 * want anyone to find it anyway.
	 */
	if (asoc->temp)
		return;

	/* Now just add it to our list of asocs */
	list_add_tail(&asoc->asocs, &ep->asocs);

	/* Increment the backlog value for a TCP-style listening socket. */
	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
		sk->sk_ack_backlog++;
}

/* Free the endpoint structure.  Delay cleanup until
 * all users have released their reference count on this structure.
 */
void sctp_endpoint_free(struct sctp_endpoint *ep)
{
	ep->base.dead = true;

	ep->base.sk->sk_state = SCTP_SS_CLOSED;

	/* Unlink this endpoint, so we can't find it again! */
	sctp_unhash_endpoint(ep);

	sctp_endpoint_put(ep);
}

/* Final destructor for endpoint.  */
static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
{
	struct sock *sk;

	if (unlikely(!ep->base.dead)) {
		WARN(1, "Attempt to destroy undead endpoint %p!\n", ep);
		return;
	}

	/* Free the digest buffer */
	kfree(ep->digest);

	/* SCTP-AUTH: Free up AUTH releated data such as shared keys
	 * chunks and hmacs arrays that were allocated
	 */
	sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
	kfree(ep->auth_hmacs_list);
	kfree(ep->auth_chunk_list);

	/* AUTH - Free any allocated HMAC transform containers */
	sctp_auth_destroy_hmacs(ep->auth_hmacs);

	/* Cleanup. */
	sctp_inq_free(&ep->base.inqueue);
	sctp_bind_addr_free(&ep->base.bind_addr);

	memset(ep->secret_key, 0, sizeof(ep->secret_key));

	/* Give up our hold on the sock. */
	sk = ep->base.sk;
	if (sk != NULL) {
		/* Remove and free the port */
		if (sctp_sk(sk)->bind_hash)
			sctp_put_port(sk);

		sock_put(sk);
	}

	kfree(ep);
	SCTP_DBG_OBJCNT_DEC(ep);
}

/* Hold a reference to an endpoint. */
void sctp_endpoint_hold(struct sctp_endpoint *ep)
{
	atomic_inc(&ep->base.refcnt);
}

/* Release a reference to an endpoint and clean up if there are
 * no more references.
 */
void sctp_endpoint_put(struct sctp_endpoint *ep)
{
	if (atomic_dec_and_test(&ep->base.refcnt))
		sctp_endpoint_destroy(ep);
}

/* Is this the endpoint we are looking for?  */
struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
					       struct net *net,
					       const union sctp_addr *laddr)
{
	struct sctp_endpoint *retval = NULL;

	if ((htons(ep->base.bind_addr.port) == laddr->v4.sin_port) &&
	    net_eq(sock_net(ep->base.sk), net)) {
		if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
					 sctp_sk(ep->base.sk)))
			retval = ep;
	}

	return retval;
}

/* Find the association that goes with this chunk.
 * We lookup the transport from hashtable at first, then get association
 * through t->assoc.
 */
struct sctp_association *sctp_endpoint_lookup_assoc(
	const struct sctp_endpoint *ep,
	const union sctp_addr *paddr,
	struct sctp_transport **transport)
{
	struct sctp_association *asoc = NULL;
	struct sctp_transport *t;

	*transport = NULL;

	/* If the local port is not set, there can't be any associations
	 * on this endpoint.
	 */
	if (!ep->base.bind_addr.port)
		return NULL;

	rcu_read_lock();
	t = sctp_epaddr_lookup_transport(ep, paddr);
	if (!t)
		goto out;

	*transport = t;
	asoc = t->asoc;
out:
	rcu_read_unlock();
	return asoc;
}

/* Look for any peeled off association from the endpoint that matches the
 * given peer address.
 */
int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
				const union sctp_addr *paddr)
{
	struct sctp_sockaddr_entry *addr;
	struct sctp_bind_addr *bp;
	struct net *net = sock_net(ep->base.sk);

	bp = &ep->base.bind_addr;
	/* This function is called with the socket lock held,
	 * so the address_list can not change.
	 */
	list_for_each_entry(addr, &bp->address_list, list) {
		if (sctp_has_association(net, &addr->a, paddr))
			return 1;
	}

	return 0;
}

/* Do delayed input processing.  This is scheduled by sctp_rcv().
 * This may be called on BH or task time.
 */
static void sctp_endpoint_bh_rcv(struct work_struct *work)
{
	struct sctp_endpoint *ep =
		container_of(work, struct sctp_endpoint,
			     base.inqueue.immediate);
	struct sctp_association *asoc;
	struct sock *sk;
	struct net *net;
	struct sctp_transport *transport;
	struct sctp_chunk *chunk;
	struct sctp_inq *inqueue;
	sctp_subtype_t subtype;
	sctp_state_t state;
	int error = 0;
	int first_time = 1;	/* is this the first time through the loop */

	if (ep->base.dead)
		return;

	asoc = NULL;
	inqueue = &ep->base.inqueue;
	sk = ep->base.sk;
	net = sock_net(sk);

	while (NULL != (chunk = sctp_inq_pop(inqueue))) {
		subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);

		/* If the first chunk in the packet is AUTH, do special
		 * processing specified in Section 6.3 of SCTP-AUTH spec
		 */
		if (first_time && (subtype.chunk == SCTP_CID_AUTH)) {
			struct sctp_chunkhdr *next_hdr;

			next_hdr = sctp_inq_peek(inqueue);
			if (!next_hdr)
				goto normal;

			/* If the next chunk is COOKIE-ECHO, skip the AUTH
			 * chunk while saving a pointer to it so we can do
			 * Authentication later (during cookie-echo
			 * processing).
			 */
			if (next_hdr->type == SCTP_CID_COOKIE_ECHO) {
				chunk->auth_chunk = skb_clone(chunk->skb,
								GFP_ATOMIC);
				chunk->auth = 1;
				continue;
			}
		}
normal:
		/* We might have grown an association since last we
		 * looked, so try again.
		 *
		 * This happens when we've just processed our
		 * COOKIE-ECHO chunk.
		 */
		if (NULL == chunk->asoc) {
			asoc = sctp_endpoint_lookup_assoc(ep,
							  sctp_source(chunk),
							  &transport);
			chunk->asoc = asoc;
			chunk->transport = transport;
		}

		state = asoc ? asoc->state : SCTP_STATE_CLOSED;
		if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
			continue;

		/* Remember where the last DATA chunk came from so we
		 * know where to send the SACK.
		 */
		if (asoc && sctp_chunk_is_data(chunk))
			asoc->peer.last_data_from = chunk->transport;
		else {
			SCTP_INC_STATS(sock_net(ep->base.sk), SCTP_MIB_INCTRLCHUNKS);
			if (asoc)
				asoc->stats.ictrlchunks++;
		}

		if (chunk->transport)
			chunk->transport->last_time_heard = ktime_get();

		error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype, state,
				   ep, asoc, chunk, GFP_ATOMIC);

		if (error && chunk)
			chunk->pdiscard = 1;

		/* Check to see if the endpoint is freed in response to
		 * the incoming chunk. If so, get out of the while loop.
		 */
		if (!sctp_sk(sk)->ep)
			break;

		if (first_time)
			first_time = 0;
	}
}
Commit	Line	Data
60c778b2	1	/* SCTP kernel implementation
1da177e4 LT	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	*
60c778b2	9	* This file is part of the SCTP kernel implementation
1da177e4 LT	10	*
	11	* This abstraction represents an SCTP endpoint.
	12	*
60c778b2	13	* The SCTP implementation is free software;
1da177e4 LT	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	*
60c778b2	19	* The SCTP implementation is distributed in the hope that it
1da177e4 LT	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
4b2f13a2 JK	26	* along with GNU CC; see the file COPYING. If not, see
4b2f13a2 JK	27	* <http://www.gnu.org/licenses/>.
1da177e4 LT	28	*
	29	* Please send any bug reports or fixes you make to the
	30	* email address(es):
91705c61	31	* lksctp developers <linux-sctp@vger.kernel.org>
1da177e4	32	*
1da177e4 LT	33	* Written or modified by:
	34	* La Monte H.P. Yarroll <piggy@acm.org>
	35	* Karl Knutson <karl@athena.chicago.il.us>
	36	* Jon Grimm <jgrimm@austin.ibm.com>
	37	* Daisy Chang <daisyc@us.ibm.com>
	38	* Dajiang Zhang <dajiang.zhang@nokia.com>
1da177e4 LT	39	*/
	40
	41	#include <linux/types.h>
1da177e4 LT	42	#include <linux/slab.h>
	43	#include <linux/in.h>
	44	#include <linux/random.h> /* get_random_bytes() */
1da177e4 LT	45	#include <net/sock.h>
	46	#include <net/ipv6.h>
	47	#include <net/sctp/sctp.h>
	48	#include <net/sctp/sm.h>
	49
	50	/* Forward declarations for internal helpers. */
c4028958	51	static void sctp_endpoint_bh_rcv(struct work_struct *work);
1da177e4 LT	52
	53	/*
	54	* Initialize the base fields of the endpoint structure.
	55	*/
	56	static struct sctp_endpoint sctp_endpoint_init(struct sctp_endpoint ep,
3182cd84	57	struct sock *sk,
dd0fc66f	58	gfp_t gfp)
1da177e4	59	{
e1fc3b14	60	struct net *net = sock_net(sk);
a29a5bd4 VY	61	struct sctp_hmac_algo_param *auth_hmacs = NULL;
	62	struct sctp_chunks_param *auth_chunks = NULL;
	63	struct sctp_shared_key *null_key;
	64	int err;
	65
b68dbcab VY	66	ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp);
	67	if (!ep->digest)
	68	return NULL;
	69
b14878cc VY	70	ep->auth_enable = net->sctp.auth_enable;
b14878cc VY	71	if (ep->auth_enable) {
a29a5bd4 VY	72	/* Allocate space for HMACS and CHUNKS authentication
	73	* variables. There are arrays that we encode directly
	74	* into parameters to make the rest of the operations easier.
	75	*/
	76	auth_hmacs = kzalloc(sizeof(sctp_hmac_algo_param_t) +
	77	sizeof(__u16) * SCTP_AUTH_NUM_HMACS, gfp);
	78	if (!auth_hmacs)
	79	goto nomem;
	80
	81	auth_chunks = kzalloc(sizeof(sctp_chunks_param_t) +
	82	SCTP_NUM_CHUNK_TYPES, gfp);
	83	if (!auth_chunks)
	84	goto nomem;
	85
	86	/* Initialize the HMACS parameter.
	87	* SCTP-AUTH: Section 3.3
	88	* Every endpoint supporting SCTP chunk authentication MUST
	89	* support the HMAC based on the SHA-1 algorithm.
	90	*/
	91	auth_hmacs->param_hdr.type = SCTP_PARAM_HMAC_ALGO;
	92	auth_hmacs->param_hdr.length =
	93	htons(sizeof(sctp_paramhdr_t) + 2);
	94	auth_hmacs->hmac_ids[0] = htons(SCTP_AUTH_HMAC_ID_SHA1);
	95
	96	/* Initialize the CHUNKS parameter */
	97	auth_chunks->param_hdr.type = SCTP_PARAM_CHUNKS;
5e739d17	98	auth_chunks->param_hdr.length = htons(sizeof(sctp_paramhdr_t));
a29a5bd4 VY	99
	100	/* If the Add-IP functionality is enabled, we must
	101	* authenticate, ASCONF and ASCONF-ACK chunks
	102	*/
e1fc3b14	103	if (net->sctp.addip_enable) {
a29a5bd4 VY	104	auth_chunks->chunks[0] = SCTP_CID_ASCONF;
a29a5bd4 VY	105	auth_chunks->chunks[1] = SCTP_CID_ASCONF_ACK;
cb0dc77d AV	106	auth_chunks->param_hdr.length =
cb0dc77d AV	107	htons(sizeof(sctp_paramhdr_t) + 2);
a29a5bd4 VY	108	}
	109	}
	110
1da177e4 LT	111	/* Initialize the base structure. */
	112	/* What type of endpoint are we? */
	113	ep->base.type = SCTP_EP_TYPE_SOCKET;
	114
	115	/* Initialize the basic object fields. */
	116	atomic_set(&ep->base.refcnt, 1);
0022d2dd	117	ep->base.dead = false;
1da177e4 LT	118
	119	/* Create an input queue. */
	120	sctp_inq_init(&ep->base.inqueue);
	121
	122	/* Set its top-half handler */
c4028958	123	sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);
1da177e4 LT	124
	125	/* Initialize the bind addr area */
	126	sctp_bind_addr_init(&ep->base.bind_addr, 0);
1da177e4 LT	127
	128	/* Remember who we are attached to. */
	129	ep->base.sk = sk;
	130	sock_hold(ep->base.sk);
	131
	132	/* Create the lists of associations. */
	133	INIT_LIST_HEAD(&ep->asocs);
	134
1da177e4	135	/* Use SCTP specific send buffer space queues. */
e1fc3b14	136	ep->sndbuf_policy = net->sctp.sndbuf_policy;
4d93df0a	137
561b1733	138	sk->sk_data_ready = sctp_data_ready;
1da177e4 LT	139	sk->sk_write_space = sctp_write_space;
	140	sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
	141
049b3ff5	142	/* Get the receive buffer policy for this endpoint */
e1fc3b14	143	ep->rcvbuf_policy = net->sctp.rcvbuf_policy;
049b3ff5	144
1da177e4	145	/* Initialize the secret key used with cookie. */
570617e7	146	get_random_bytes(ep->secret_key, sizeof(ep->secret_key));
1da177e4	147
a29a5bd4 VY	148	/* SCTP-AUTH extensions*/
a29a5bd4 VY	149	INIT_LIST_HEAD(&ep->endpoint_shared_keys);
81ce0dbc	150	null_key = sctp_auth_shkey_create(0, gfp);
a29a5bd4 VY	151	if (!null_key)
	152	goto nomem;
	153
	154	list_add(&null_key->key_list, &ep->endpoint_shared_keys);
	155
02582e9b	156	/* Allocate and initialize transorms arrays for supported HMACs. */
a29a5bd4 VY	157	err = sctp_auth_init_hmacs(ep, gfp);
	158	if (err)
	159	goto nomem_hmacs;
	160
	161	/* Add the null key to the endpoint shared keys list and
	162	* set the hmcas and chunks pointers.
	163	*/
	164	ep->auth_hmacs_list = auth_hmacs;
	165	ep->auth_chunk_list = auth_chunks;
28aa4c26	166	ep->prsctp_enable = net->sctp.prsctp_enable;
a29a5bd4	167
1da177e4	168	return ep;
a29a5bd4 VY	169
	170	nomem_hmacs:
	171	sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
	172	nomem:
	173	/* Free all allocations */
	174	kfree(auth_hmacs);
	175	kfree(auth_chunks);
	176	kfree(ep->digest);
	177	return NULL;
	178
1da177e4 LT	179	}
	180
	181	/* Create a sctp_endpoint with all that boring stuff initialized.
	182	* Returns NULL if there isn't enough memory.
	183	*/
dd0fc66f	184	struct sctp_endpoint sctp_endpoint_new(struct sock sk, gfp_t gfp)
1da177e4 LT	185	{
	186	struct sctp_endpoint *ep;
	187
	188	/* Build a local endpoint. */
939cfa75	189	ep = kzalloc(sizeof(*ep), gfp);
1da177e4 LT	190	if (!ep)
1da177e4 LT	191	goto fail;
939cfa75	192
1da177e4 LT	193	if (!sctp_endpoint_init(ep, sk, gfp))
1da177e4 LT	194	goto fail_init;
ff2266cd	195
1da177e4 LT	196	SCTP_DBG_OBJCNT_INC(ep);
	197	return ep;
	198
	199	fail_init:
	200	kfree(ep);
	201	fail:
	202	return NULL;
	203	}
	204
	205	/* Add an association to an endpoint. */
	206	void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
	207	struct sctp_association *asoc)
	208	{
	209	struct sock *sk = ep->base.sk;
	210
de76e695 VY	211	/* If this is a temporary association, don't bother
	212	* since we'll be removing it shortly and don't
	213	* want anyone to find it anyway.
	214	*/
	215	if (asoc->temp)
	216	return;
	217
1da177e4 LT	218	/* Now just add it to our list of asocs */
	219	list_add_tail(&asoc->asocs, &ep->asocs);
	220
	221	/* Increment the backlog value for a TCP-style listening socket. */
	222	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
	223	sk->sk_ack_backlog++;
	224	}
	225
	226	/* Free the endpoint structure. Delay cleanup until
	227	* all users have released their reference count on this structure.
	228	*/
	229	void sctp_endpoint_free(struct sctp_endpoint *ep)
	230	{
0022d2dd	231	ep->base.dead = true;
cfdeef32 VY	232
	233	ep->base.sk->sk_state = SCTP_SS_CLOSED;
	234
	235	/* Unlink this endpoint, so we can't find it again! */
	236	sctp_unhash_endpoint(ep);
	237
1da177e4 LT	238	sctp_endpoint_put(ep);
	239	}
	240
	241	/* Final destructor for endpoint. */
	242	static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
	243	{
0a2fbac1	244	struct sock *sk;
1da177e4	245
bb33381d DB	246	if (unlikely(!ep->base.dead)) {
	247	WARN(1, "Attempt to destroy undead endpoint %p!\n", ep);
	248	return;
	249	}
1da177e4	250
b68dbcab VY	251	/* Free the digest buffer */
	252	kfree(ep->digest);
	253
a29a5bd4 VY	254	/* SCTP-AUTH: Free up AUTH releated data such as shared keys
	255	* chunks and hmacs arrays that were allocated
	256	*/
	257	sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
	258	kfree(ep->auth_hmacs_list);
	259	kfree(ep->auth_chunk_list);
	260
	261	/* AUTH - Free any allocated HMAC transform containers */
	262	sctp_auth_destroy_hmacs(ep->auth_hmacs);
	263
1da177e4 LT	264	/* Cleanup. */
	265	sctp_inq_free(&ep->base.inqueue);
	266	sctp_bind_addr_free(&ep->base.bind_addr);
	267
570617e7	268	memset(ep->secret_key, 0, sizeof(ep->secret_key));
b5c37fe6	269
1da177e4	270	/* Give up our hold on the sock. */
0a2fbac1 DB	271	sk = ep->base.sk;
	272	if (sk != NULL) {
	273	/* Remove and free the port */
	274	if (sctp_sk(sk)->bind_hash)
	275	sctp_put_port(sk);
	276
	277	sock_put(sk);
	278	}
1da177e4	279
ff2266cd DB	280	kfree(ep);
ff2266cd DB	281	SCTP_DBG_OBJCNT_DEC(ep);
1da177e4 LT	282	}
	283
	284	/* Hold a reference to an endpoint. */
	285	void sctp_endpoint_hold(struct sctp_endpoint *ep)
	286	{
	287	atomic_inc(&ep->base.refcnt);
	288	}
	289
	290	/* Release a reference to an endpoint and clean up if there are
	291	* no more references.
	292	*/
	293	void sctp_endpoint_put(struct sctp_endpoint *ep)
	294	{
	295	if (atomic_dec_and_test(&ep->base.refcnt))
	296	sctp_endpoint_destroy(ep);
	297	}
	298
	299	/* Is this the endpoint we are looking for? */
	300	struct sctp_endpoint sctp_endpoint_is_match(struct sctp_endpoint ep,
4cdadcbc	301	struct net *net,
1da177e4 LT	302	const union sctp_addr *laddr)
1da177e4 LT	303	{
559cf710	304	struct sctp_endpoint *retval = NULL;
1da177e4	305
4cdadcbc EB	306	if ((htons(ep->base.bind_addr.port) == laddr->v4.sin_port) &&
4cdadcbc EB	307	net_eq(sock_net(ep->base.sk), net)) {
1da177e4	308	if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
559cf710	309	sctp_sk(ep->base.sk)))
1da177e4	310	retval = ep;
1da177e4 LT	311	}
1da177e4 LT	312
1da177e4 LT	313	return retval;
	314	}
	315
	316	/* Find the association that goes with this chunk.
4f008781 XL	317	* We lookup the transport from hashtable at first, then get association
4f008781 XL	318	* through t->assoc.
1da177e4	319	*/
c79c0666	320	struct sctp_association *sctp_endpoint_lookup_assoc(
1da177e4 LT	321	const struct sctp_endpoint *ep,
	322	const union sctp_addr *paddr,
	323	struct sctp_transport **transport)
	324	{
123ed979	325	struct sctp_association *asoc = NULL;
4f008781	326	struct sctp_transport *t;
1da177e4	327
123ed979	328	*transport = NULL;
deb85a6e VY	329
	330	/* If the local port is not set, there can't be any associations
	331	* on this endpoint.
	332	*/
	333	if (!ep->base.bind_addr.port)
5cb2cd68 XL	334	return NULL;
	335
	336	rcu_read_lock();
4f008781	337	t = sctp_epaddr_lookup_transport(ep, paddr);
dd7445ad	338	if (!t)
4f008781	339	goto out;
deb85a6e	340
4f008781 XL	341	*transport = t;
4f008781 XL	342	asoc = t->asoc;
deb85a6e	343	out:
5cb2cd68	344	rcu_read_unlock();
123ed979	345	return asoc;
1da177e4 LT	346	}
1da177e4 LT	347
1da177e4 LT	348	/* Look for any peeled off association from the endpoint that matches the
	349	* given peer address.
	350	*/
	351	int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
	352	const union sctp_addr *paddr)
	353	{
1da177e4 LT	354	struct sctp_sockaddr_entry *addr;
1da177e4 LT	355	struct sctp_bind_addr *bp;
4110cc25	356	struct net *net = sock_net(ep->base.sk);
1da177e4	357
1da177e4	358	bp = &ep->base.bind_addr;
559cf710 VY	359	/* This function is called with the socket lock held,
	360	* so the address_list can not change.
	361	*/
	362	list_for_each_entry(addr, &bp->address_list, list) {
4110cc25	363	if (sctp_has_association(net, &addr->a, paddr))
1da177e4	364	return 1;
1da177e4	365	}
1da177e4 LT	366
	367	return 0;
	368	}
	369
	370	/* Do delayed input processing. This is scheduled by sctp_rcv().
	371	* This may be called on BH or task time.
	372	*/
c4028958	373	static void sctp_endpoint_bh_rcv(struct work_struct *work)
1da177e4	374	{
c4028958 DH	375	struct sctp_endpoint *ep =
	376	container_of(work, struct sctp_endpoint,
	377	base.inqueue.immediate);
1da177e4 LT	378	struct sctp_association *asoc;
1da177e4 LT	379	struct sock *sk;
55e26eb9	380	struct net *net;
1da177e4 LT	381	struct sctp_transport *transport;
	382	struct sctp_chunk *chunk;
	383	struct sctp_inq *inqueue;
	384	sctp_subtype_t subtype;
	385	sctp_state_t state;
	386	int error = 0;
42b2aa86	387	int first_time = 1; /* is this the first time through the loop */
1da177e4 LT	388
	389	if (ep->base.dead)
	390	return;
	391
	392	asoc = NULL;
	393	inqueue = &ep->base.inqueue;
	394	sk = ep->base.sk;
55e26eb9	395	net = sock_net(sk);
1da177e4 LT	396
	397	while (NULL != (chunk = sctp_inq_pop(inqueue))) {
	398	subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
	399
bbd0d598 VY	400	/* If the first chunk in the packet is AUTH, do special
	401	* processing specified in Section 6.3 of SCTP-AUTH spec
	402	*/
	403	if (first_time && (subtype.chunk == SCTP_CID_AUTH)) {
	404	struct sctp_chunkhdr *next_hdr;
	405
	406	next_hdr = sctp_inq_peek(inqueue);
	407	if (!next_hdr)
	408	goto normal;
	409
	410	/* If the next chunk is COOKIE-ECHO, skip the AUTH
	411	* chunk while saving a pointer to it so we can do
	412	* Authentication later (during cookie-echo
	413	* processing).
	414	*/
	415	if (next_hdr->type == SCTP_CID_COOKIE_ECHO) {
	416	chunk->auth_chunk = skb_clone(chunk->skb,
	417	GFP_ATOMIC);
	418	chunk->auth = 1;
	419	continue;
	420	}
	421	}
	422	normal:
1da177e4 LT	423	/* We might have grown an association since last we
	424	* looked, so try again.
	425	*
	426	* This happens when we've just processed our
	427	* COOKIE-ECHO chunk.
	428	*/
	429	if (NULL == chunk->asoc) {
	430	asoc = sctp_endpoint_lookup_assoc(ep,
	431	sctp_source(chunk),
	432	&transport);
	433	chunk->asoc = asoc;
	434	chunk->transport = transport;
	435	}
	436
	437	state = asoc ? asoc->state : SCTP_STATE_CLOSED;
bbd0d598 VY	438	if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
bbd0d598 VY	439	continue;
1da177e4 LT	440
	441	/* Remember where the last DATA chunk came from so we
	442	* know where to send the SACK.
	443	*/
	444	if (asoc && sctp_chunk_is_data(chunk))
	445	asoc->peer.last_data_from = chunk->transport;
196d6759	446	else {
b01a2407	447	SCTP_INC_STATS(sock_net(ep->base.sk), SCTP_MIB_INCTRLCHUNKS);
196d6759 MB	448	if (asoc)
	449	asoc->stats.ictrlchunks++;
	450	}
1da177e4 LT	451
1da177e4 LT	452	if (chunk->transport)
e575235f	453	chunk->transport->last_time_heard = ktime_get();
1da177e4	454
55e26eb9	455	error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype, state,
d808ad9a	456	ep, asoc, chunk, GFP_ATOMIC);
1da177e4 LT	457
	458	if (error && chunk)
	459	chunk->pdiscard = 1;
	460
	461	/* Check to see if the endpoint is freed in response to
	462	* the incoming chunk. If so, get out of the while loop.
	463	*/
	464	if (!sctp_sk(sk)->ep)
	465	break;
bbd0d598 VY	466
	467	if (first_time)
	468	first_time = 0;
1da177e4 LT	469	}
1da177e4 LT	470	}