patch-2.4.23 linux-2.4.23/net/sctp/endpointola.c

• Lines: 397
• Date: 2003-11-28 10:26:21.000000000 -0800
• Orig file: linux-2.4.22/net/sctp/endpointola.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.22/net/sctp/endpointola.c linux-2.4.23/net/sctp/endpointola.c
@@ -0,0 +1,396 @@
+/* SCTP kernel reference 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 reference Implementation
+ *
+ * This abstraction represents an SCTP endpoint.
+ *
+ * This file is part of the implementation of the add-IP extension,
+ * based on <draft-ietf-tsvwg-addip-sctp-02.txt> June 29, 2001,
+ * for the SCTP kernel reference Implementation.
+ *
+ * The SCTP reference 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 reference 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, write to
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <lksctp-developers@lists.sourceforge.net>
+ *
+ * Or submit a bug report through the following website:
+ *    http://www.sf.net/projects/lksctp
+ *
+ * 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>
+ *
+ * Any bugs reported given to us we will try to fix... any fixes shared will
+ * be incorporated into the next SCTP release.
+ */
+
+#include <linux/types.h>
+#include <linux/sched.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 sctp_endpoint *ep);
+
+/* 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, int gfp)
+{
+	struct sctp_endpoint *ep;
+
+	/* Build a local endpoint. */
+	ep = t_new(struct sctp_endpoint, gfp);
+	if (!ep)
+		goto fail;
+	if (!sctp_endpoint_init(ep, sk, gfp))
+		goto fail_init;
+	ep->base.malloced = 1;
+	SCTP_DBG_OBJCNT_INC(ep);
+	return ep;
+
+fail_init:
+	kfree(ep);
+fail:
+	return NULL;
+}
+
+/*
+ * Initialize the base fields of the endpoint structure.
+ */
+struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
+					 struct sock *sk, int gfp)
+{
+	struct sctp_opt *sp = sctp_sk(sk);
+	memset(ep, 0, sizeof(struct sctp_endpoint));
+
+	/* 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 = 0;
+	ep->base.malloced = 1;
+
+	/* Create an input queue.  */
+	sctp_inq_init(&ep->base.inqueue);
+
+	/* Set its top-half handler */
+	sctp_inq_set_th_handler(&ep->base.inqueue,
+				(void (*)(void *))sctp_endpoint_bh_rcv, ep);
+
+	/* Initialize the bind addr area */
+	sctp_bind_addr_init(&ep->base.bind_addr, 0);
+	ep->base.addr_lock = RW_LOCK_UNLOCKED;
+
+	/* 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);
+
+	/* Set up the base timeout information.  */
+	ep->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
+	ep->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
+		SCTP_DEFAULT_TIMEOUT_T1_COOKIE;
+	ep->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
+		SCTP_DEFAULT_TIMEOUT_T1_INIT;
+	ep->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] =
+		sp->rtoinfo.srto_initial;
+	ep->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
+
+	/* sctpimpguide-05 Section 2.12.2
+	 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
+	 * recommended value of 5 times 'RTO.Max'.
+	 */
+        ep->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
+		= 5 * sp->rtoinfo.srto_max;
+
+	ep->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] =
+		SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
+	ep->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
+		SCTP_DEFAULT_TIMEOUT_SACK;
+	ep->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
+		sp->autoclose * HZ;
+
+	/* Set up the default send/receive buffer space.  */
+
+	/* FIXME - Should the min and max window size be configurable
+	 * sysctl parameters as opposed to be constants?
+	 */
+	sk->rcvbuf = SCTP_DEFAULT_MAXWINDOW;
+	sk->sndbuf = SCTP_DEFAULT_MAXWINDOW * 2;
+
+	/* Use SCTP specific send buffer space queues.  */
+	sk->write_space = sctp_write_space;
+	sk->use_write_queue = 1;
+
+	/* Initialize the secret key used with cookie. */
+	get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
+	ep->last_key = ep->current_key = 0;
+	ep->key_changed_at = jiffies;
+
+	ep->debug_name = "unnamedEndpoint";
+	return ep;
+}
+
+/* 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;
+
+	/* 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_SOCKET_TCP == sctp_sk(sk)->type) &&
+	    (SCTP_SS_LISTENING == sk->state))
+		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 = 1;
+	sctp_endpoint_put(ep);
+}
+
+/* Final destructor for endpoint.  */
+void sctp_endpoint_destroy(struct sctp_endpoint *ep)
+{
+	SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
+
+	ep->base.sk->state = SCTP_SS_CLOSED;
+
+	/* Unlink this endpoint, so we can't find it again! */
+	sctp_unhash_endpoint(ep);
+
+	/* Free up the HMAC transform. */
+	if (sctp_sk(ep->base.sk)->hmac)
+		sctp_crypto_free_tfm(sctp_sk(ep->base.sk)->hmac);
+
+	/* Cleanup. */
+	sctp_inq_free(&ep->base.inqueue);
+	sctp_bind_addr_free(&ep->base.bind_addr);
+
+	/* Remove and free the port */
+	if (ep->base.sk->prev != NULL)
+		sctp_put_port(ep->base.sk);
+
+	/* Give up our hold on the sock. */
+	if (ep->base.sk)
+		sock_put(ep->base.sk);
+
+	/* Finally, free up our memory. */
+	if (ep->base.malloced) {
+		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,
+					       const union sctp_addr *laddr)
+{
+	struct sctp_endpoint *retval;
+
+	sctp_read_lock(&ep->base.addr_lock);
+	if (ep->base.bind_addr.port == laddr->v4.sin_port) {
+		if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
+					 sctp_sk(ep->base.sk))) {
+			retval = ep;
+			goto out;
+		}
+	}
+
+	retval = NULL;
+
+out:
+	sctp_read_unlock(&ep->base.addr_lock);
+	return retval;
+}
+
+/* Find the association that goes with this chunk.
+ * We do a linear search of the associations for this endpoint.
+ * We return the matching transport address too.
+ */
+struct sctp_association *__sctp_endpoint_lookup_assoc(
+	const struct sctp_endpoint *ep,
+	const union sctp_addr *paddr,
+	struct sctp_transport **transport)
+{
+	int rport;
+	struct sctp_association *asoc;
+	struct list_head *pos;
+
+	rport = paddr->v4.sin_port;
+
+	list_for_each(pos, &ep->asocs) {
+		asoc = list_entry(pos, struct sctp_association, asocs);
+		if (rport == asoc->peer.port) {
+			sctp_read_lock(&asoc->base.addr_lock);
+			*transport = sctp_assoc_lookup_paddr(asoc, paddr);
+			sctp_read_unlock(&asoc->base.addr_lock);
+
+			if (*transport)
+				return asoc;
+		}
+	}
+
+	*transport = NULL;
+	return NULL;
+}
+
+/* Lookup association on an endpoint based on a peer address.  BH-safe.  */
+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;
+
+	sctp_local_bh_disable();
+	asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
+	sctp_local_bh_enable();
+
+	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 list_head *pos;
+	struct sockaddr_storage_list *addr;
+	sctp_bind_addr_t *bp;
+
+	sctp_read_lock(&ep->base.addr_lock);
+	bp = &ep->base.bind_addr;
+	list_for_each(pos, &bp->address_list) {
+		addr = list_entry(pos, struct sockaddr_storage_list, list);
+		if (sctp_has_association(&addr->a, paddr)) {
+			sctp_read_unlock(&ep->base.addr_lock);
+			return 1;
+		}
+	}
+	sctp_read_unlock(&ep->base.addr_lock);
+
+	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 sctp_endpoint *ep)
+{
+	struct sctp_association *asoc;
+	struct sock *sk;
+	struct sctp_transport *transport;
+	sctp_chunk_t *chunk;
+	struct sctp_inq *inqueue;
+	sctp_subtype_t subtype;
+	sctp_state_t state;
+	int error = 0;
+
+	if (ep->base.dead)
+		return;
+
+	asoc = NULL;
+	inqueue = &ep->base.inqueue;
+	sk = ep->base.sk;
+
+	while (NULL != (chunk = sctp_inq_pop(inqueue))) {
+		subtype.chunk = chunk->chunk_hdr->type;
+
+		/* 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;
+
+		/* 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(SctpInCtrlChunks);
+
+		if (chunk->transport)
+			chunk->transport->last_time_heard = jiffies;
+
+		error = sctp_do_sm(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;
+	}
+}