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

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diff -urN linux-2.4.22/net/sctp/socket.c linux-2.4.23/net/sctp/socket.c
@@ -0,0 +1,3639 @@
+/* Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001-2003 International Business Machines, Corp.
+ * Copyright (c) 2001-2003 Intel Corp.
+ * Copyright (c) 2001-2002 Nokia, Inc.
+ * Copyright (c) 2001 La Monte H.P. Yarroll
+ *
+ * This file is part of the SCTP kernel reference Implementation
+ *
+ * These functions interface with the sockets layer to implement the
+ * SCTP Extensions for the Sockets API.
+ *
+ * Note that the descriptions from the specification are USER level
+ * functions--this file is the functions which populate the struct proto
+ * for SCTP which is the BOTTOM of the sockets interface.
+ *
+ * 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>
+ *    Narasimha Budihal     <narsi@refcode.org>
+ *    Karl Knutson          <karl@athena.chicago.il.us>
+ *    Jon Grimm             <jgrimm@us.ibm.com>
+ *    Xingang Guo           <xingang.guo@intel.com>
+ *    Daisy Chang           <daisyc@us.ibm.com>
+ *    Sridhar Samudrala     <samudrala@us.ibm.com>
+ *    Inaky Perez-Gonzalez  <inaky.gonzalez@intel.com>
+ *    Ardelle Fan	    <ardelle.fan@intel.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/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/wait.h>
+#include <linux/time.h>
+#include <linux/ip.h>
+#include <linux/fcntl.h>
+#include <linux/poll.h>
+#include <linux/init.h>
+
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/route.h>
+#include <net/ipv6.h>
+#include <net/inet_common.h>
+
+#include <linux/socket.h> /* for sa_family_t */
+#include <net/sock.h>
+#include <net/sctp/sctp.h>
+
+/* WARNING:  Please do not remove the SCTP_STATIC attribute to
+ * any of the functions below as they are used to export functions
+ * used by a project regression testsuite.
+ */
+
+/* Forward declarations for internal helper functions. */
+static int sctp_writeable(struct sock *sk);
+static inline int sctp_wspace(struct sctp_association *asoc);
+static inline void sctp_set_owner_w(sctp_chunk_t *chunk);
+static void sctp_wfree(struct sk_buff *skb);
+static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
+				int msg_len);
+static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p);
+static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
+static int sctp_wait_for_accept(struct sock *sk, long timeo);
+static inline int sctp_verify_addr(struct sock *, union sctp_addr *, int);
+static int sctp_bindx_add(struct sock *, struct sockaddr_storage *, int);
+static int sctp_bindx_rem(struct sock *, struct sockaddr_storage *, int);
+static int sctp_do_bind(struct sock *, union sctp_addr *, int);
+static int sctp_autobind(struct sock *sk);
+static void sctp_sock_migrate(struct sock *, struct sock *,
+			      struct sctp_association *, sctp_socket_type_t);
+static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG;
+
+/* Look up the association by its id.  If this is not a UDP-style
+ * socket, the ID field is always ignored.
+ */
+struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
+{
+	struct sctp_association *asoc = NULL;
+
+	/* If this is not a UDP-style socket, assoc id should be
+	 * ignored.
+	 */
+	if (SCTP_SOCKET_UDP != sctp_sk(sk)->type) {
+		if (!list_empty(&sctp_sk(sk)->ep->asocs))
+			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
+					  struct sctp_association, asocs);
+		return asoc;
+	}
+
+	/* First, verify that this is a kernel address. */
+	if (sctp_is_valid_kaddr((unsigned long) id)) {
+		struct sctp_association *temp;
+
+		/* Verify that this _is_ an sctp_association
+		 * data structure and if so, that the socket matches.
+		 */
+		temp = (struct sctp_association *)id;
+		if ((SCTP_ASSOC_EYECATCHER == temp->eyecatcher) &&
+		    (temp->base.sk == sk))
+			asoc = temp;
+	}
+
+	return asoc;
+}
+
+/* API 3.1.2 bind() - UDP Style Syntax
+ * The syntax of bind() is,
+ *
+ *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
+ *
+ *   sd      - the socket descriptor returned by socket().
+ *   addr    - the address structure (struct sockaddr_in or struct
+ *             sockaddr_in6 [RFC 2553]),
+ *   addrlen - the size of the address structure.
+ *
+ * The caller should use struct sockaddr_storage described in RFC 2553
+ * to represent addr for portability reason.
+ */
+int sctp_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
+{
+	int retval = 0;
+
+	sctp_lock_sock(sk);
+
+	SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, uaddr: %p, addr_len: %d)\n",
+			  sk, uaddr, addr_len);
+
+	/* Disallow binding twice. */
+	if (!sctp_sk(sk)->ep->base.bind_addr.port)
+		retval = sctp_do_bind(sk, (union sctp_addr *)uaddr,
+				      addr_len);
+	else
+		retval = -EINVAL;
+
+	sctp_release_sock(sk);
+
+	return retval;
+}
+
+static long sctp_get_port_local(struct sock *, union sctp_addr *);
+
+/* Verify this is a valid sockaddr. */
+static struct sctp_af *sctp_sockaddr_af(struct sctp_opt *opt,
+					union sctp_addr *addr, int len)
+{
+	struct sctp_af *af;
+
+	/* Check minimum size.  */
+	if (len < sizeof (struct sockaddr))
+		return NULL;
+
+	/* Does this PF support this AF? */
+	if (!opt->pf->af_supported(addr->sa.sa_family))
+		return NULL;
+
+	/* If we get this far, af is valid. */
+	af = sctp_get_af_specific(addr->sa.sa_family);
+
+	if (len < af->sockaddr_len)
+		return NULL;
+
+	return af;
+}
+
+/* Bind a local address either to an endpoint or to an association.  */
+SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
+{
+	struct sctp_opt *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
+	sctp_bind_addr_t *bp = &ep->base.bind_addr;
+	struct sctp_af *af;
+	unsigned short snum;
+	int ret = 0;
+
+	SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d)\n",
+			  sk, addr, len);
+
+	/* Common sockaddr verification. */
+	af = sctp_sockaddr_af(sp, addr, len);
+	if (!af)
+		return -EINVAL;
+
+	/* PF specific bind() address verification. */
+	if (!sp->pf->bind_verify(sp, addr))
+		return -EADDRNOTAVAIL;
+
+	snum= ntohs(addr->v4.sin_port);
+
+	SCTP_DEBUG_PRINTK("sctp_do_bind: port: %d, new port: %d\n",
+			  bp->port, snum);
+
+	/* We must either be unbound, or bind to the same port.  */
+	if (bp->port && (snum != bp->port)) {
+		SCTP_DEBUG_PRINTK("sctp_do_bind:"
+				  " New port %d does not match existing port "
+				  "%d.\n", snum, bp->port);
+		return -EINVAL;
+	}
+
+	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
+		return -EACCES;
+
+	/* Make sure we are allowed to bind here.
+	 * The function sctp_get_port_local() does duplicate address
+	 * detection.
+	 */
+	if ((ret = sctp_get_port_local(sk, addr))) {
+		if (ret == (long) sk) {
+			/* This endpoint has a conflicting address. */
+			return -EINVAL;
+		} else {
+			return -EADDRINUSE;
+		}
+	}
+
+	/* Refresh ephemeral port.  */
+	if (!snum)
+		snum = (sk)->num;
+
+	/* Add the address to the bind address list.  */
+	sctp_local_bh_disable();
+	sctp_write_lock(&ep->base.addr_lock);
+
+	/* Use GFP_ATOMIC since BHs are disabled.  */
+	addr->v4.sin_port = ntohs(addr->v4.sin_port);
+	ret = sctp_add_bind_addr(bp, addr, GFP_ATOMIC);
+	addr->v4.sin_port = htons(addr->v4.sin_port);
+	if (!ret && !bp->port)
+		bp->port = snum;
+	sctp_write_unlock(&ep->base.addr_lock);
+	sctp_local_bh_enable();
+
+	/* Copy back into socket for getsockname() use. */
+	if (!ret) {
+		(sk)->sport = htons((sk)->num);
+		af->to_sk_saddr(addr, sk);
+	}
+
+	return ret;
+}
+
+/* API 8.1 sctp_bindx()
+ *
+ * The syntax of sctp_bindx() is,
+ *
+ *   ret = sctp_bindx(int sd,
+ *                    struct sockaddr_storage *addrs,
+ * 		      int addrcnt,
+ * 		      int flags);
+ *
+ * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
+ * If the sd is an IPv6 socket, the addresses passed can either be IPv4
+ * or IPv6 addresses.
+ *
+ * A single address may be specified as INADDR_ANY or IPV6_ADDR_ANY, see
+ * section 3.1.2 for this usage.
+ *
+ * addrs is a pointer to an array of one or more socket addresses.  Each
+ * address is contained in a struct sockaddr_storage, so each address is
+ * fixed length. The caller specifies the number of addresses in the
+ * array with addrcnt.
+ *
+ * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns -1,
+ * and sets errno to the appropriate error code. [ Editor's note: need
+ * to fill in all error code? ]
+ *
+ * For SCTP, the port given in each socket address must be the same, or
+ * sctp_bindx() will fail, setting errno to EINVAL .
+ *
+ * The flags parameter is formed from the bitwise OR of zero or
+ * more of the following currently defined flags:
+ *
+ *     SCTP_BINDX_ADD_ADDR
+ *     SCTP_BINDX_REM_ADDR
+ *
+ * SCTP_BIND_ADD_ADDR directs SCTP to add the given addresses to the
+ * association, and SCTP_BIND_REM_ADDR directs SCTP to remove the given
+ * addresses from the association. The two flags are mutually exclusive;
+ * if both are given, sctp_bindx() will fail with EINVAL.  A caller may not
+ * remove all addresses from an association; sctp_bindx() will reject such
+ * an attempt with EINVAL.
+ *
+ * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
+ * additional addresses with an endpoint after calling bind().  Or use
+ * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
+ * socket is associated with so that no new association accepted will be
+ * associated with those addresses.
+ *
+ * SCTP_BIND_ADD_ADDR is defined as 0, so that it becomes the default
+ * behavior for sctp_bindx() when no flags are given.
+ *
+ * Adding and removing addresses from a connected association is optional
+ * functionality. Implementations that do not support this functionality
+ * should return EOPNOTSUPP.
+ *
+ * NOTE: This could be integrated into sctp_setsockopt_bindx(),
+ * but keeping it this way makes it easier if sometime sys_bindx is
+ * added.
+ */
+
+/* Unprotected by locks. Call only with socket lock sk->lock held! See
+ * sctp_bindx() for a lock-protected call.
+ */
+
+static int __sctp_bindx(struct sock *sk, struct sockaddr_storage *addrs,
+			int addrcnt, int flags)
+{
+	int retval = 0;
+
+	SCTP_DEBUG_PRINTK("__sctp_bindx(sk: %p, addrs: %p, addrcnt: %d, "
+			  "flags: %s)\n", sk, addrs, addrcnt,
+			  (BINDX_ADD_ADDR == flags) ? "ADD" :
+			  ((BINDX_REM_ADDR == flags) ? "REM" : "BOGUS"));
+
+	switch (flags) {
+	case BINDX_ADD_ADDR:
+		retval = sctp_bindx_add(sk, addrs, addrcnt);
+		break;
+
+	case BINDX_REM_ADDR:
+		retval = sctp_bindx_rem(sk, addrs, addrcnt);
+		break;
+
+	default:
+		retval = -EINVAL;
+		break;
+        };
+
+	return retval;
+}
+
+/* BINDX with locks.
+ *
+ * NOTE: Currently unused at all ...
+ */
+int sctp_bindx(struct sock *sk, struct sockaddr_storage *addrs, int addrcnt,
+	       int flags)
+{
+	int retval;
+
+	sctp_lock_sock(sk);
+	retval = __sctp_bindx(sk, addrs, addrcnt, flags);
+	sctp_release_sock(sk);
+
+	return retval;
+}
+
+/* Add a list of addresses as bind addresses to local endpoint or
+ * association.
+ *
+ * Basically run through each address specified in the addrs/addrcnt
+ * array/length pair, determine if it is IPv6 or IPv4 and call
+ * sctp_do_bind() on it.
+ *
+ * If any of them fails, then the operation will be reversed and the
+ * ones that were added will be removed.
+ *
+ * Only __sctp_bindx() is supposed to call this function.
+ */
+int sctp_bindx_add(struct sock *sk, struct sockaddr_storage *addrs, int addrcnt)
+{
+	int cnt;
+	int retval = 0;
+	int addr_len;
+
+	SCTP_DEBUG_PRINTK("sctp_bindx_add (sk: %p, addrs: %p, addrcnt: %d)\n",
+			  sk, addrs, addrcnt);
+
+	for (cnt = 0; cnt < addrcnt; cnt++) {
+		/* The list may contain either IPv4 or IPv6 address;
+		 * determine the address length for walking thru the list.
+		 */
+		switch (((struct sockaddr *)&addrs[cnt])->sa_family) {
+		case AF_INET:
+			addr_len = sizeof(struct sockaddr_in);
+			break;
+
+		case AF_INET6:
+			addr_len = sizeof(struct sockaddr_in6);
+			break;
+
+		default:
+			retval = -EINVAL;
+			goto err_bindx_add;
+		};
+
+		retval = sctp_do_bind(sk, (union sctp_addr *)&addrs[cnt],
+				      addr_len);
+
+err_bindx_add:
+		if (retval < 0) {
+			/* Failed. Cleanup the ones that has been added */
+			if (cnt > 0)
+				sctp_bindx_rem(sk, addrs, cnt);
+			return retval;
+		}
+	}
+
+	/* Notify the peer(s), assuming we have (an) association(s).
+	 * FIXME: for UDP, we have a 1-1-many mapping amongst sk, ep and asoc,
+	 *        so we don't have to do much work on locating associations.
+	 *
+	 * However, when the separation of ep and asoc kicks in, especially
+	 * for TCP style connection, it becomes n-1-n mapping.  We will need
+	 * to do more fine work.  Until then, hold my peace.
+	 *							--xguo
+	 *
+	 * Really, I don't think that will be a problem.  The bind()
+	 * call on a socket will either know the endpoint
+	 * (e.g. TCP-style listen()ing socket, or UDP-style socket),
+	 * or exactly one association.  The former case is EXACTLY
+	 * what we have now.  In the former case we know the
+	 * association already.					--piggy
+	 *
+	 * This code will be working on either a UDP style or a TCP style
+	 * socket, or say either an endpoint or an association. The socket
+	 * type verification code need to be added later before calling the
+	 * ADDIP code.
+	 * 							--daisy
+	 */
+
+#if CONFIG_IP_SCTP_ADDIP
+	/* Add these addresses to all associations on this endpoint.  */
+	if (retval >= 0) {
+		struct list_head *pos;
+		struct sctp_endpoint *ep;
+		struct sctp_association *asoc;
+		ep = sctp_sk(sk)->ep;
+
+		list_for_each(pos, &ep->asocs) {
+			asoc = list_entry(pos, struct sctp_association, asocs);
+
+			sctp_addip_addr_config(asoc,
+					       SCTP_PARAM_ADD_IP,
+					       addrs, addrcnt);
+		}
+	}
+#endif
+
+	return retval;
+}
+
+/* Remove a list of addresses from bind addresses list.  Do not remove the
+ * last address.
+ *
+ * Basically run through each address specified in the addrs/addrcnt
+ * array/length pair, determine if it is IPv6 or IPv4 and call
+ * sctp_del_bind() on it.
+ *
+ * If any of them fails, then the operation will be reversed and the
+ * ones that were removed will be added back.
+ *
+ * At least one address has to be left; if only one address is
+ * available, the operation will return -EBUSY.
+ *
+ * Only __sctp_bindx() is supposed to call this function.
+ */
+int sctp_bindx_rem(struct sock *sk, struct sockaddr_storage *addrs, int addrcnt)
+{
+	struct sctp_opt *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
+	int cnt;
+	sctp_bind_addr_t *bp = &ep->base.bind_addr;
+	int retval = 0;
+	union sctp_addr saveaddr;
+
+	SCTP_DEBUG_PRINTK("sctp_bindx_rem (sk: %p, addrs: %p, addrcnt: %d)\n",
+			  sk, addrs, addrcnt);
+
+	for (cnt = 0; cnt < addrcnt; cnt++) {
+		/* If there is only one bind address, there is nothing more
+		 * to be removed (we need at least one address here).
+		 */
+		if (list_empty(&bp->address_list)) {
+			retval = -EBUSY;
+			goto err_bindx_rem;
+		}
+
+		/* The list may contain either IPv4 or IPv6 address;
+		 * determine the address length for walking thru the list.
+		 */
+		switch (((struct sockaddr *)&addrs[cnt])->sa_family) {
+		case AF_INET:
+			saveaddr = *((union sctp_addr *)
+				     &addrs[cnt]);
+			saveaddr.v4.sin_port = ntohs(saveaddr.v4.sin_port);
+			/* Verify the port.  */
+			if (saveaddr.v4.sin_port != bp->port) {
+				retval = -EINVAL;
+				goto err_bindx_rem;
+			}
+			break;
+
+		case AF_INET6:
+			saveaddr = *((union sctp_addr *)
+				     &addrs[cnt]);
+			saveaddr.v6.sin6_port =
+				ntohs(saveaddr.v6.sin6_port);
+			/* verify the port */
+			if (saveaddr.v6.sin6_port != bp->port) {
+				retval = -EINVAL;
+				goto err_bindx_rem;
+			}
+			break;
+
+		default:
+			retval = -EINVAL;
+			goto err_bindx_rem;
+		};
+
+		/* FIXME - There is probably a need to check if sk->saddr and
+		 * sk->rcv_addr are currently set to one of the addresses to
+		 * be removed. This is something which needs to be looked into
+		 * when we are fixing the outstanding issues with multi-homing
+		 * socket routing and failover schemes. Refer to comments in
+		 * sctp_do_bind(). -daisy
+		 */
+		sctp_local_bh_disable();
+		sctp_write_lock(&ep->base.addr_lock);
+
+		retval = sctp_del_bind_addr(bp, &saveaddr);
+
+		sctp_write_unlock(&ep->base.addr_lock);
+		sctp_local_bh_enable();
+
+err_bindx_rem:
+		if (retval < 0) {
+			/* Failed. Add the ones that has been removed back */
+			if (cnt > 0)
+				sctp_bindx_add(sk, addrs, cnt);
+			return retval;
+		}
+	}
+
+	/*
+	 * This code will be working on either a UDP style or a TCP style
+	 * socket, * or say either an endpoint or an association. The socket
+	 * type verification code need to be added later before calling the
+	 * ADDIP code.
+	 * 							--daisy
+	 */
+#if CONFIG_IP_SCTP_ADDIP
+	/* Remove these addresses from all associations on this endpoint.  */
+	if (retval >= 0) {
+		struct list_head *pos;
+		struct sctp_endpoint *ep;
+		struct sctp_association *asoc;
+
+		ep = sctp_sk(sk)->ep;
+		list_for_each(pos, &ep->asocs) {
+			asoc = list_entry(pos, struct sctp_association, asocs);
+			sctp_addip_addr_config(asoc, SCTP_PARAM_DEL_IP,
+					       addrs, addrcnt);
+		}
+	}
+#endif
+	return retval;
+}
+
+/* Helper for tunneling sys_bindx() requests through sctp_setsockopt()
+ *
+ * Basically do nothing but copying the addresses from user to kernel
+ * land and invoking sctp_bindx on the sk. This is used for tunneling
+ * the sctp_bindx() [sys_bindx()] request through sctp_setsockopt()
+ * from userspace.
+ *
+ * Note I don't use move_addr_to_kernel(): the reason is we would be
+ * iterating over an array of struct sockaddr_storage passing always
+ * what we know is a good size (sizeof (struct sock...)), so it is
+ * pointless. Instead check the whole area for read access and copy
+ * it.
+ *
+ * We don't use copy_from_user() for optimization: we first do the
+ * sanity checks (buffer size -fast- and access check-healthy
+ * pointer); if all of those succeed, then we can alloc the memory
+ * (expensive operation) needed to copy the data to kernel. Then we do
+ * the copying without checking the user space area
+ * (__copy_from_user()).
+ *
+ * On exit there is no need to do sockfd_put(), sys_setsockopt() does
+ * it.
+ *
+ * sk        The sk of the socket
+ * addrs     The pointer to the addresses in user land
+ * addrssize Size of the addrs buffer
+ * op        Operation to perform (add or remove, see the flags of
+ *           sctp_bindx)
+ *
+ * Returns 0 if ok, <0 errno code on error.
+ */
+SCTP_STATIC int sctp_setsockopt_bindx(struct sock* sk,
+				      struct sockaddr_storage *addrs,
+				      int addrssize, int op)
+{
+	struct sockaddr_storage *kaddrs;
+	int err;
+	size_t addrcnt;
+
+	SCTP_DEBUG_PRINTK("sctp_do_setsocktopt_bindx: sk %p addrs %p"
+			  " addrssize %d opt %d\n", sk, addrs, addrssize, op);
+
+	/* Do we have an integer number of structs sockaddr_storage?  */
+	if (unlikely(addrssize <= 0 ||
+		     addrssize % sizeof(struct sockaddr_storage) != 0))
+		return -EINVAL;
+
+	/* Check the user passed a healthy pointer.  */
+	if (unlikely(!access_ok(VERIFY_READ, addrs, addrssize)))
+		return -EFAULT;
+
+	/* Alloc space for the address array in kernel memory.  */
+	kaddrs = (struct sockaddr_storage *) kmalloc(addrssize, GFP_KERNEL);
+	if (unlikely(!kaddrs))
+		return -ENOMEM;
+
+	if (copy_from_user(kaddrs, addrs, addrssize)) {
+		kfree(kaddrs);
+		return -EFAULT;
+	}
+
+	addrcnt = addrssize / sizeof(struct sockaddr_storage);
+	err = __sctp_bindx(sk, kaddrs, addrcnt, op);   /* Do the work. */
+	kfree(kaddrs);
+
+	return err;
+}
+
+/* API 3.1.4 close() - UDP Style Syntax
+ * Applications use close() to perform graceful shutdown (as described in
+ * Section 10.1 of [SCTP]) on ALL the associations currently represented
+ * by a UDP-style socket.
+ *
+ * The syntax is
+ *
+ *   ret = close(int sd);
+ *
+ *   sd      - the socket descriptor of the associations to be closed.
+ *
+ * To gracefully shutdown a specific association represented by the
+ * UDP-style socket, an application should use the sendmsg() call,
+ * passing no user data, but including the appropriate flag in the
+ * ancillary data (see Section xxxx).
+ *
+ * If sd in the close() call is a branched-off socket representing only
+ * one association, the shutdown is performed on that association only.
+ */
+SCTP_STATIC void sctp_close(struct sock *sk, long timeout)
+{
+	struct sctp_endpoint *ep;
+	struct sctp_association *asoc;
+	struct list_head *pos, *temp;
+
+	SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p...)\n", sk);
+
+	sctp_lock_sock(sk);
+	sk->shutdown = SHUTDOWN_MASK;
+
+	ep = sctp_sk(sk)->ep;
+
+	/* Walk all associations on a socket, not on an endpoint.  */
+	list_for_each_safe(pos, temp, &ep->asocs) {
+		asoc = list_entry(pos, struct sctp_association, asocs);
+
+		/* A closed association can still be in the list if it
+		 * belongs to a TCP-style listening socket that is not
+		 * yet accepted.
+		 */
+		if ((SCTP_SOCKET_TCP == sctp_sk(sk)->type) &&
+		    (SCTP_STATE_CLOSED == asoc->state)) {
+			sctp_unhash_established(asoc);
+			sctp_association_free(asoc);
+		} else
+			sctp_primitive_SHUTDOWN(asoc, NULL);
+	}
+
+	/* Clean up any skbs sitting on the receive queue.  */
+	skb_queue_purge(&sk->receive_queue);
+	skb_queue_purge(&sctp_sk(sk)->pd_lobby);
+
+	/* This will run the backlog queue.  */
+	sctp_release_sock(sk);
+
+	/* Supposedly, no process has access to the socket, but
+	 * the net layers still may.
+	 */
+	sctp_local_bh_disable();
+	sctp_bh_lock_sock(sk);
+
+	/* Hold the sock, since inet_sock_release() will put sock_put()
+	 * and we have just a little more cleanup.
+	 */
+	sock_hold(sk);
+	inet_sock_release(sk);
+
+	sctp_bh_unlock_sock(sk);
+	sctp_local_bh_enable();
+
+	sock_put(sk);
+
+	SCTP_DBG_OBJCNT_DEC(sock);
+}
+
+/* Handle EPIPE error. */
+static int sctp_error(struct sock *sk, int flags, int err)
+{
+	if (err == -EPIPE)
+		err = sock_error(sk) ? : -EPIPE;
+	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
+		send_sig(SIGPIPE, current, 0);
+	return err;
+}
+
+/* API 3.1.3 sendmsg() - UDP Style Syntax
+ *
+ * An application uses sendmsg() and recvmsg() calls to transmit data to
+ * and receive data from its peer.
+ *
+ *  ssize_t sendmsg(int socket, const struct msghdr *message,
+ *                  int flags);
+ *
+ *  socket  - the socket descriptor of the endpoint.
+ *  message - pointer to the msghdr structure which contains a single
+ *            user message and possibly some ancillary data.
+ *
+ *            See Section 5 for complete description of the data
+ *            structures.
+ *
+ *  flags   - flags sent or received with the user message, see Section
+ *            5 for complete description of the flags.
+ *
+ * Note:  This function could use a rewrite especially when explicit
+ * connect support comes in.
+ */
+/* BUG:  We do not implement the equivalent of wait_for_tcp_memory(). */
+
+SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
+
+SCTP_STATIC int sctp_sendmsg(struct sock *sk, struct msghdr *msg, int msg_len)
+{
+	struct sctp_opt *sp;
+	struct sctp_endpoint *ep;
+	struct sctp_association *new_asoc=NULL, *asoc=NULL;
+	struct sctp_transport *transport;
+	sctp_chunk_t *chunk = NULL;
+	union sctp_addr to;
+	struct sockaddr *msg_name = NULL;
+	struct sctp_sndrcvinfo default_sinfo = { 0 };
+	struct sctp_sndrcvinfo *sinfo;
+	struct sctp_initmsg *sinit;
+	sctp_assoc_t associd = NULL;
+	sctp_cmsgs_t cmsgs = { 0 };
+	int err;
+	sctp_scope_t scope;
+	long timeo;
+	__u16 sinfo_flags = 0;
+	struct sk_buff_head chunks;
+	int msg_flags = msg->msg_flags;
+
+	SCTP_DEBUG_PRINTK("sctp_sendmsg(sk: %p, msg: %p, msg_len: %d)\n",
+			  sk, msg, msg_len);
+
+	err = 0;
+	sp = sctp_sk(sk);
+	ep = sp->ep;
+
+	SCTP_DEBUG_PRINTK("Using endpoint: %s.\n", ep->debug_name);
+
+	if ((SCTP_SOCKET_TCP == sp->type) &&
+	    (SCTP_SS_ESTABLISHED != sk->state)) {
+		err = -EPIPE;
+		goto out_nounlock;
+	}
+
+	/* Parse out the SCTP CMSGs.  */
+	err = sctp_msghdr_parse(msg, &cmsgs);
+
+	if (err) {
+		SCTP_DEBUG_PRINTK("msghdr parse err = %x\n", err);
+		goto out_nounlock;
+	}
+
+	/* Fetch the destination address for this packet.  This
+	 * address only selects the association--it is not necessarily
+	 * the address we will send to.
+	 * For a peeled-off socket, msg_name is ignored.
+	 */
+	if ((SCTP_SOCKET_UDP_HIGH_BANDWIDTH != sp->type) && msg->msg_name) {
+		int msg_namelen = msg->msg_namelen;
+
+		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
+				       msg_namelen);
+		if (err)
+			return err;
+
+		if (msg_namelen > sizeof(to))
+			msg_namelen = sizeof(to);
+		memcpy(&to, msg->msg_name, msg_namelen);
+		SCTP_DEBUG_PRINTK("Just memcpy'd. msg_name is "
+				  "0x%x:%u.\n",
+				  to.v4.sin_addr.s_addr, to.v4.sin_port);
+
+		to.v4.sin_port = ntohs(to.v4.sin_port);
+		msg_name = msg->msg_name;
+	}
+
+	sinfo = cmsgs.info;
+	sinit = cmsgs.init;
+
+	/* Did the user specify SNDRCVINFO?  */
+	if (sinfo) {
+		sinfo_flags = sinfo->sinfo_flags;
+		associd = sinfo->sinfo_assoc_id;
+	}
+
+	SCTP_DEBUG_PRINTK("msg_len: %Zd, sinfo_flags: 0x%x\n",
+			  msg_len, sinfo_flags);
+
+	/* If MSG_EOF is set, no data can be sent. Disallow sending zero
+	 * length messages when MSG_EOF|MSG_ABORT is not set.
+	 * If MSG_ABORT is set, the message length could be non zero with
+	 * the msg_iov set to the user abort reason.
+ 	 */
+	if (((sinfo_flags & MSG_EOF) && (msg_len > 0)) ||
+	    (!(sinfo_flags & (MSG_EOF|MSG_ABORT)) && (msg_len == 0))) {
+		err = -EINVAL;
+		goto out_nounlock;
+	}
+
+	sctp_lock_sock(sk);
+
+	transport = NULL;
+
+	SCTP_DEBUG_PRINTK("About to look up association.\n");
+
+	/* If a msg_name has been specified, assume this is to be used.  */
+	if (msg_name) {
+		/* Look for a matching association on the endpoint. */
+		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
+		if (!asoc) {
+			/* If we could not find a matching association on the
+			 * endpoint, make sure that there is no peeled-off
+			 * association on another socket.
+			 */
+			if (sctp_endpoint_is_peeled_off(ep, &to)) {
+				err = -EADDRNOTAVAIL;
+				goto out_unlock;
+			}
+		}
+	} else {
+		asoc = sctp_id2assoc(sk, associd);
+		if (!asoc) {
+			err = -EINVAL;
+			goto out_unlock;
+		}
+	}
+
+	if (asoc) {
+		SCTP_DEBUG_PRINTK("Just looked up association: "
+				  "%s. \n", asoc->debug_name);
+
+		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED 
+		 * socket that has an association in CLOSED state. This can
+		 * happen when an accepted socket has an association that is
+		 * already CLOSED. 
+		 */
+		if ((SCTP_STATE_CLOSED == asoc->state) &&
+		    (SCTP_SOCKET_TCP == sp->type)) {
+			err = -EPIPE;
+			goto out_unlock;
+		}
+
+		if (sinfo_flags & MSG_EOF) {
+			SCTP_DEBUG_PRINTK("Shutting down association: %p\n",
+					  asoc);
+			sctp_primitive_SHUTDOWN(asoc, NULL);
+			err = 0;
+			goto out_unlock;
+		}
+		if (sinfo_flags & MSG_ABORT) {
+			SCTP_DEBUG_PRINTK("Aborting association: %p\n", asoc);
+			sctp_primitive_ABORT(asoc, msg);
+			err = 0;
+			goto out_unlock;
+		}
+	}
+
+	/* Do we need to create the association?  */
+	if (!asoc) {
+		SCTP_DEBUG_PRINTK("There is no association yet.\n");
+
+		/* Check for invalid stream against the stream counts,
+		 * either the default or the user specified stream counts.
+		 */
+		if (sinfo) {
+			if (!sinit || (sinit && !sinit->sinit_num_ostreams)) {
+				/* Check against the defaults. */
+				if (sinfo->sinfo_stream >=
+				    sp->initmsg.sinit_num_ostreams) {
+					err = -EINVAL;
+					goto out_unlock;
+				}
+			} else {
+				/* Check against the requested.  */
+				if (sinfo->sinfo_stream >=
+				    sinit->sinit_num_ostreams) {
+					err = -EINVAL;
+					goto out_unlock;
+				}
+			}
+		}
+
+		/*
+		 * API 3.1.2 bind() - UDP Style Syntax
+		 * If a bind() or sctp_bindx() is not called prior to a
+		 * sendmsg() call that initiates a new association, the
+		 * system picks an ephemeral port and will choose an address
+		 * set equivalent to binding with a wildcard address.
+		 */
+		if (!ep->base.bind_addr.port) {
+			if (sctp_autobind(sk)) {
+				err = -EAGAIN;
+				goto out_unlock;
+			}
+		}
+
+		scope = sctp_scope(&to);
+		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
+		if (!new_asoc) {
+			err = -ENOMEM;
+			goto out_unlock;
+		}
+		asoc = new_asoc;
+
+		/* If the SCTP_INIT ancillary data is specified, set all
+		 * the association init values accordingly.
+		 */
+		if (sinit) {
+			if (sinit->sinit_num_ostreams) {
+				asoc->c.sinit_num_ostreams =
+					sinit->sinit_num_ostreams;
+			}
+			if (sinit->sinit_max_instreams) {
+				asoc->c.sinit_max_instreams =
+					sinit->sinit_max_instreams;
+			}
+			if (sinit->sinit_max_attempts) {
+				asoc->max_init_attempts
+					= sinit->sinit_max_attempts;
+			}
+			if (sinit->sinit_max_init_timeo) {
+				asoc->max_init_timeo
+					= sinit->sinit_max_init_timeo * HZ;
+			}
+		}
+
+		/* Prime the peer's transport structures.  */
+		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL);
+		if (!transport) {
+			err = -ENOMEM;
+			goto out_free;
+		}
+		err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
+		if (err < 0) {
+			err = -ENOMEM;
+			goto out_free;
+		}
+	}
+
+	/* ASSERT: we have a valid association at this point.  */
+	SCTP_DEBUG_PRINTK("We have a valid association.\n");
+
+	if (!sinfo) {
+		/* If the user didn't specify SNDRCVINFO, make up one with
+		 * some defaults.
+		 */
+		default_sinfo.sinfo_stream = asoc->defaults.stream;
+		default_sinfo.sinfo_flags = asoc->defaults.flags;
+		default_sinfo.sinfo_ppid = asoc->defaults.ppid;
+		default_sinfo.sinfo_context = asoc->defaults.context;
+		default_sinfo.sinfo_timetolive = asoc->defaults.timetolive;
+		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
+		sinfo = &default_sinfo;
+	}
+
+	/* API 7.1.7, the sndbuf size per association bounds the
+	 * maximum size of data that can be sent in a single send call.
+	 */
+	if (msg_len > sk->sndbuf) {
+		err = -EMSGSIZE;
+		goto out_free;
+	}
+
+	/* If fragmentation is disabled and the message length exceeds the
+	 * association fragmentation point, return EMSGSIZE.  The I-D
+	 * does not specify what this error is, but this looks like
+	 * a great fit.
+	 */
+	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
+		err = -EMSGSIZE;
+		goto out_free;
+	}
+
+	if (sinfo) {
+		/* Check for invalid stream. */
+		if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
+			err = -EINVAL;
+			goto out_free;
+		}
+	}
+
+	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
+	if (!sctp_wspace(asoc)) {
+		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
+		if (err)
+			goto out_free;
+	}
+
+	/* Break the message into multiple chunks of maximum size. */
+	skb_queue_head_init(&chunks);
+	err = sctp_datachunks_from_user(asoc, sinfo, msg, msg_len, &chunks);
+	if (err)
+		goto out_free;
+
+	/* Auto-connect, if we aren't connected already. */
+	if (SCTP_STATE_CLOSED == asoc->state) {
+		err = sctp_primitive_ASSOCIATE(asoc, NULL);
+		if (err < 0)
+			goto out_free;
+		SCTP_DEBUG_PRINTK("We associated primitively.\n");
+	}
+
+	/* Now send the (possibly) fragmented message. */
+	while ((chunk = (sctp_chunk_t *)__skb_dequeue(&chunks))) {
+
+		/* Do accounting for the write space.  */
+		sctp_set_owner_w(chunk);
+
+		/* This flag, in the UDP model, requests the SCTP stack to
+		 * override the primary destination address with the
+		 * address found with the sendto/sendmsg call.
+		 */
+		if (sinfo_flags & MSG_ADDR_OVER) {
+			if (!msg->msg_name) {
+				err = -EINVAL;
+				goto out_free;
+			}
+			chunk->transport = sctp_assoc_lookup_paddr(asoc, &to);
+			if (!chunk->transport) {
+				err = -EINVAL;
+				goto out_free;
+			}
+		}
+
+		/* Send it to the lower layers.  */
+		sctp_primitive_SEND(asoc, chunk);
+		SCTP_DEBUG_PRINTK("We sent primitively.\n");
+	}
+
+	if (!err) {
+		err = msg_len;
+		goto out_unlock;
+	}
+	/* If we are already past ASSOCIATE, the lower
+	 * layers are responsible for association cleanup.
+	 */
+	goto out_free_chunk;
+
+out_free:
+	if (new_asoc)
+		sctp_association_free(asoc);
+
+out_free_chunk:
+	if (chunk)
+		sctp_free_chunk(chunk);
+
+out_unlock:
+	sctp_release_sock(sk);
+
+out_nounlock:
+	return sctp_error(sk, msg_flags, err);
+
+#if 0
+do_sock_err:
+	if (msg_len)
+		err = msg_len;
+	else
+		err = sock_error(sk);
+	goto out;
+
+do_interrupted:
+	if (msg_len)
+		err = msg_len;
+	goto out;
+#endif /* 0 */
+}
+
+/* This is an extended version of skb_pull() that removes the data from the
+ * start of a skb even when data is spread across the list of skb's in the
+ * frag_list. len specifies the total amount of data that needs to be removed.
+ * when 'len' bytes could be removed from the skb, it returns 0.
+ * If 'len' exceeds the total skb length,  it returns the no. of bytes that
+ * could not be removed.
+ */
+static int sctp_skb_pull(struct sk_buff *skb, int len)
+{
+	struct sk_buff *list;
+	int skb_len = skb_headlen(skb);
+	int rlen;
+
+	if (len <= skb_len) {
+		__skb_pull(skb, len);
+		return 0;
+	}
+	len -= skb_len;
+	__skb_pull(skb, skb_len);
+
+	for (list = skb_shinfo(skb)->frag_list; list; list = list->next) {
+		rlen = sctp_skb_pull(list, len);
+		skb->len -= (len-rlen);
+		skb->data_len -= (len-rlen);
+
+		if (!rlen)
+			return 0;
+
+		len = rlen;
+	}
+
+	return len;
+}
+
+/* API 3.1.3  recvmsg() - UDP Style Syntax
+ *
+ *  ssize_t recvmsg(int socket, struct msghdr *message,
+ *                    int flags);
+ *
+ *  socket  - the socket descriptor of the endpoint.
+ *  message - pointer to the msghdr structure which contains a single
+ *            user message and possibly some ancillary data.
+ *
+ *            See Section 5 for complete description of the data
+ *            structures.
+ *
+ *  flags   - flags sent or received with the user message, see Section
+ *            5 for complete description of the flags.
+ */
+static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
+
+SCTP_STATIC int sctp_recvmsg(struct sock *sk, struct msghdr *msg, int len,
+			     int noblock, int flags, int *addr_len)
+{
+	struct sctp_ulpevent *event = NULL;
+	struct sctp_opt *sp = sctp_sk(sk);
+	struct sk_buff *skb;
+	int copied;
+	int err = 0;
+	int skb_len;
+
+	SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %d, %s: %d, %s: "
+			  "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg,
+			  "len", len, "knoblauch", noblock,
+			  "flags", flags, "addr_len", addr_len);
+
+	sctp_lock_sock(sk);
+
+	if ((SCTP_SOCKET_TCP == sp->type) &&
+	    (SCTP_SS_ESTABLISHED != sk->state)) {
+		err = -ENOTCONN;
+		goto out;
+	}
+
+	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
+	if (!skb)
+		goto out;
+
+	/* Get the total length of the skb including any skb's in the
+	 * frag_list.
+	 */
+	skb_len = skb->len;
+
+	copied = skb_len;
+	if (copied > len)
+		copied = len;
+
+	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
+
+	event = sctp_skb2event(skb);
+
+	if (err)
+		goto out_free;
+
+	sock_recv_timestamp(msg, sk, skb);
+	if (sctp_ulpevent_is_notification(event)) {
+		msg->msg_flags |= MSG_NOTIFICATION;
+		sp->pf->event_msgname(event, msg->msg_name, addr_len);
+	} else {
+		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
+	}
+
+	/* Check if we allow SCTP_SNDRCVINFO. */
+	if (sp->subscribe.sctp_data_io_event)
+		sctp_ulpevent_read_sndrcvinfo(event, msg);
+#if 0
+	/* FIXME: we should be calling IP/IPv6 layers.  */
+	if (sk->protinfo.af_inet.cmsg_flags)
+		ip_cmsg_recv(msg, skb);
+#endif
+
+	err = copied;
+
+	/* If skb's length exceeds the user's buffer, update the skb and
+	 * push it back to the receive_queue so that the next call to
+	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
+	 */
+	if (skb_len > copied) {
+		msg->msg_flags &= ~MSG_EOR;
+		if (flags & MSG_PEEK)
+			goto out_free;
+		sctp_skb_pull(skb, copied);
+		skb_queue_head(&sk->receive_queue, skb);
+
+		/* When only partial message is copied to the user, increase
+		 * rwnd by that amount. If all the data in the skb is read,
+		 * rwnd is updated when the skb's destructor is called via
+		 * sctp_ulpevent_free().
+		 */
+		sctp_assoc_rwnd_increase(event->event_asoc, copied);
+		goto out;
+	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
+		   (event->msg_flags & MSG_EOR))
+		msg->msg_flags |= MSG_EOR;
+	else
+		msg->msg_flags &= ~MSG_EOR;
+
+out_free:
+	sctp_ulpevent_free(event); /* Free the skb. */
+out:
+	sctp_release_sock(sk);
+	return err;
+}
+
+static int sctp_setsockopt_disable_fragments(struct sock *sk,
+						    char *optval, int optlen)
+{
+	int val;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+
+	if (get_user(val, (int *)optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
+
+	return 0;
+}
+
+static int sctp_setsockopt_events(struct sock *sk, char *optval,
+					int optlen)
+{
+	if (optlen != sizeof(struct sctp_event_subscribe))
+		return -EINVAL;
+	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
+		return -EFAULT;
+	return 0;
+}
+
+static int sctp_setsockopt_autoclose(struct sock *sk, char *optval,
+					    int optlen)
+{
+	struct sctp_opt *sp = sctp_sk(sk);
+
+	/* Applicable to UDP-style socket only */
+	if (SCTP_SOCKET_TCP == sp->type)
+		return -EOPNOTSUPP;
+	if (optlen != sizeof(int))
+		return -EINVAL;
+	if (copy_from_user(&sp->autoclose, optval, optlen))
+		return -EFAULT;
+
+	sp->ep->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sp->autoclose * HZ;
+	return 0;
+}
+
+static int sctp_setsockopt_peer_addr_params(struct sock *sk,
+					    char *optval, int optlen)
+{
+	struct sctp_paddrparams params;
+	struct sctp_association *asoc;
+	union sctp_addr *addr;
+	struct sctp_transport *trans;
+	int error;
+
+	if (optlen != sizeof(struct sctp_paddrparams))
+		return -EINVAL;
+	if (copy_from_user(&params, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	addr = (union sctp_addr *) &(params.spp_address);
+
+	trans = sctp_assoc_lookup_paddr(asoc, addr);
+	if (!trans)
+		return -ENOENT;
+
+	/* Applications can enable or disable heartbeats for any peer address
+	 * of an association, modify an address's heartbeat interval, force a
+	 * heartbeat to be sent immediately, and adjust the address's maximum
+	 * number of retransmissions sent before an address is considered
+	 * unreachable.
+	 *
+	 * The value of the heartbeat interval, in milliseconds. A value of
+	 * UINT32_MAX (4294967295), when modifying the parameter, specifies
+	 * that a heartbeat should be sent immediately to the peer address,
+	 * and the current interval should remain unchanged.
+	 */
+	if (0xffffffff == params.spp_hbinterval) {
+		error = sctp_primitive_REQUESTHEARTBEAT (asoc, trans);
+		if (error)
+			return error;
+	} else {
+	/* The value of the heartbeat interval, in milliseconds. A value of 0,
+	 * when modifying the parameter, specifies that the heartbeat on this
+	 * address should be disabled.
+	 */
+		if (params.spp_hbinterval) {
+			trans->hb_allowed = 1;
+			trans->hb_interval = params.spp_hbinterval * HZ / 1000;
+		} else
+			trans->hb_allowed = 0;
+	}
+
+	/* spp_pathmaxrxt contains the maximum number of retransmissions
+	 * before this address shall be considered unreachable.
+	 */
+	trans->error_threshold = params.spp_pathmaxrxt;
+
+	return 0;
+}
+
+static int sctp_setsockopt_initmsg(struct sock *sk, char *optval, int optlen)
+{
+	if (optlen != sizeof(struct sctp_initmsg))
+		return -EINVAL;
+	if (copy_from_user(&sctp_sk(sk)->initmsg, optval, optlen))
+		return -EFAULT;
+	return 0;
+}
+
+/*
+ * 7.1.15 Set default send parameters (SET_DEFAULT_SEND_PARAM)
+ *
+ *   Applications that wish to use the sendto() system call may wish to
+ *   specify a default set of parameters that would normally be supplied
+ *   through the inclusion of ancillary data.  This socket option allows
+ *   such an application to set the default sctp_sndrcvinfo structure.
+ *   The application that wishes to use this socket option simply passes
+ *   in to this call the sctp_sndrcvinfo structure defined in Section
+ *   5.2.2) The input parameters accepted by this call include
+ *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
+ *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
+ *   to this call if the caller is using the UDP model.
+ */
+static int sctp_setsockopt_default_send_param(struct sock *sk,
+						char *optval, int optlen)
+{
+	struct sctp_sndrcvinfo info;
+	struct sctp_association *asoc;
+
+	if (optlen != sizeof(struct sctp_sndrcvinfo))
+		return -EINVAL;
+	if (copy_from_user(&info, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	asoc->defaults.stream = info.sinfo_stream;
+	asoc->defaults.flags = info.sinfo_flags;
+	asoc->defaults.ppid = info.sinfo_ppid;
+	asoc->defaults.context = info.sinfo_context;
+	asoc->defaults.timetolive = info.sinfo_timetolive;
+	return 0;
+}
+
+/* 7.1.10 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
+ *
+ * Requests that the local SCTP stack use the enclosed peer address as
+ * the association primary.  The enclosed address must be one of the
+ * association peer's addresses.
+ */
+static int sctp_setsockopt_peer_prim(struct sock *sk, char *optval, int optlen)
+{
+	struct sctp_setpeerprim prim;
+	struct sctp_association *asoc;
+	union sctp_addr *addr;
+	struct sctp_transport *trans;
+
+	if (optlen != sizeof(struct sctp_setpeerprim))
+		return -EINVAL;
+
+	if (copy_from_user(&prim, optval, sizeof(struct sctp_setpeerprim)))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	/* Find the requested address. */
+	addr = (union sctp_addr *) &(prim.sspp_addr);
+
+	trans = sctp_assoc_lookup_paddr(asoc, addr);
+	if (!trans)
+		return -ENOENT;
+
+	sctp_assoc_set_primary(asoc, trans);
+
+	return 0;
+}
+
+/*
+ *
+ * 7.1.5 SCTP_NODELAY
+ *
+ * Turn on/off any Nagle-like algorithm.  This means that packets are
+ * generally sent as soon as possible and no unnecessary delays are
+ * introduced, at the cost of more packets in the network.  Expects an
+ *  integer boolean flag.
+ */
+static int sctp_setsockopt_nodelay(struct sock *sk, char *optval,
+					int optlen)
+{
+	__u8 val;
+
+	if (optlen < sizeof(__u8))
+		return -EINVAL;
+	if (get_user(val, (__u8 *)optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
+	return 0;
+}
+
+/* API 6.2 setsockopt(), getsockopt()
+ *
+ * Applications use setsockopt() and getsockopt() to set or retrieve
+ * socket options.  Socket options are used to change the default
+ * behavior of sockets calls.  They are described in Section 7.
+ *
+ * The syntax is:
+ *
+ *   ret = getsockopt(int sd, int level, int optname, void *optval,
+ *                    int *optlen);
+ *   ret = setsockopt(int sd, int level, int optname, const void *optval,
+ *                    int optlen);
+ *
+ *   sd      - the socket descript.
+ *   level   - set to IPPROTO_SCTP for all SCTP options.
+ *   optname - the option name.
+ *   optval  - the buffer to store the value of the option.
+ *   optlen  - the size of the buffer.
+ */
+SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
+				char *optval, int optlen)
+{
+	int retval = 0;
+	char *tmp;
+
+	SCTP_DEBUG_PRINTK("sctp_setsockopt(sk: %p... optname: %d)\n",
+			  sk, optname);
+
+	/* I can hardly begin to describe how wrong this is.  This is
+	 * so broken as to be worse than useless.  The API draft
+	 * REALLY is NOT helpful here...  I am not convinced that the
+	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
+	 * are at all well-founded.
+	 */
+	if (level != SOL_SCTP) {
+		struct sctp_af *af = sctp_sk(sk)->pf->af;
+		retval = af->setsockopt(sk, level, optname, optval, optlen);
+		goto out_nounlock;
+	}
+
+	sctp_lock_sock(sk);
+
+	switch (optname) {
+	case SCTP_SOCKOPT_DEBUG_NAME:
+		/* BUG! we don't ever seem to free this memory. --jgrimm */
+		if (NULL == (tmp = kmalloc(optlen + 1, GFP_KERNEL))) {
+			retval = -ENOMEM;
+			goto out_unlock;
+		}
+
+		if (copy_from_user(tmp, optval, optlen)) {
+			retval = -EFAULT;
+			goto out_unlock;
+		}
+		tmp[optlen] = '\000';
+		sctp_sk(sk)->ep->debug_name = tmp;
+		break;
+
+	case SCTP_SOCKOPT_BINDX_ADD:
+		/* 'optlen' is the size of the addresses buffer. */
+		retval = sctp_setsockopt_bindx(sk, (struct sockaddr_storage *)
+					       optval, optlen, BINDX_ADD_ADDR);
+		break;
+
+	case SCTP_SOCKOPT_BINDX_REM:
+		/* 'optlen' is the size of the addresses buffer. */
+		retval = sctp_setsockopt_bindx(sk, (struct sockaddr_storage *)
+					       optval, optlen, BINDX_REM_ADDR);
+		break;
+
+	case SCTP_DISABLE_FRAGMENTS:
+		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
+		break;
+
+	case SCTP_SET_EVENTS:
+		retval = sctp_setsockopt_events(sk, optval, optlen);
+		break;
+
+	case SCTP_AUTOCLOSE:
+		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
+		break;
+
+	case SCTP_SET_PEER_ADDR_PARAMS:
+		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
+		break;
+
+	case SCTP_INITMSG:
+		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
+		break;
+
+	case SCTP_SET_DEFAULT_SEND_PARAM:
+		retval = sctp_setsockopt_default_send_param(sk, optval,
+							    optlen);
+		break;
+
+	case SCTP_SET_PEER_PRIMARY_ADDR:
+		retval = sctp_setsockopt_peer_prim(sk, optval, optlen);
+		break;
+
+	case SCTP_NODELAY:
+		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
+		break;
+
+	default:
+		retval = -ENOPROTOOPT;
+		break;
+	};
+
+out_unlock:
+	sctp_release_sock(sk);
+
+out_nounlock:
+	return retval;
+}
+
+/* API 3.1.6 connect() - UDP Style Syntax
+ *
+ * An application may use the connect() call in the UDP model to initiate an
+ * association without sending data.
+ *
+ * The syntax is:
+ *
+ * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
+ *
+ * sd: the socket descriptor to have a new association added to.
+ *
+ * nam: the address structure (either struct sockaddr_in or struct
+ *    sockaddr_in6 defined in RFC2553 [7]).
+ *
+ * len: the size of the address.
+ */
+SCTP_STATIC int sctp_connect(struct sock *sk, struct sockaddr *uaddr,
+			     int addr_len)
+{
+	struct sctp_opt *sp;
+	struct sctp_endpoint *ep;
+	struct sctp_association *asoc;
+	struct sctp_transport *transport;
+	union sctp_addr to;
+	struct sctp_af *af;
+	sctp_scope_t scope;
+	long timeo;
+	int err = 0;
+
+	sctp_lock_sock(sk);
+
+	SCTP_DEBUG_PRINTK("%s - sk: %p, sockaddr: %p, addr_len: %d)\n",
+			  __FUNCTION__, sk, uaddr, addr_len);
+
+	sp = sctp_sk(sk);
+	ep = sp->ep;
+
+	/* connect() cannot be done on a socket that is already in ESTABLISHED
+	 * state - UDP-style peeled off socket or a TCP-style socket that
+	 * is already connected.
+	 * It cannot be done even on a TCP-style listening socket.
+	 */
+	if ((SCTP_SS_ESTABLISHED == sk->state) ||
+	    ((SCTP_SOCKET_TCP == sp->type) &&
+	     (SCTP_SS_LISTENING == sk->state))) {
+		err = -EISCONN;
+		goto out_unlock;
+	}
+
+	err = sctp_verify_addr(sk, (union sctp_addr *)uaddr, addr_len);
+	if (err)
+		goto out_unlock;
+
+	if (addr_len > sizeof(to))
+		addr_len = sizeof(to);
+	memcpy(&to, uaddr, addr_len);
+	to.v4.sin_port = ntohs(to.v4.sin_port);
+
+	asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
+	if (asoc) {
+		if (asoc->state >= SCTP_STATE_ESTABLISHED)
+			err = -EISCONN;
+		else
+			err = -EALREADY;
+		goto out_unlock;
+	}
+
+	/* If we could not find a matching association on the endpoint,
+	 * make sure that there is no peeled-off association matching the
+	 * peer address even on another socket.
+	 */
+	if (sctp_endpoint_is_peeled_off(ep, &to)) {
+		err = -EADDRNOTAVAIL;
+		goto out_unlock;
+	}
+
+	/* If a bind() or sctp_bindx() is not called prior to a connect()
+	 * call, the system picks an ephemeral port and will choose an address
+	 * set equivalent to binding with a wildcard address.
+	 */
+	if (!ep->base.bind_addr.port) {
+		if (sctp_autobind(sk)) {
+			err = -EAGAIN;
+			goto out_unlock;
+		}
+	}
+
+	scope = sctp_scope(&to);
+	asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
+	if (!asoc) {
+		err = -ENOMEM;
+		goto out_unlock;
+  	}
+
+	/* Prime the peer's transport structures.  */
+	transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL);
+	if (!transport) {
+		sctp_association_free(asoc);
+		goto out_unlock;
+	}
+	err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
+	if (err < 0) {
+		sctp_association_free(asoc);
+		goto out_unlock;
+	}
+
+	err = sctp_primitive_ASSOCIATE(asoc, NULL);
+	if (err < 0) {
+		sctp_association_free(asoc);
+		goto out_unlock;
+	}
+
+	/* Initialize sk's dport and daddr for getpeername() */
+	(sk)->dport = htons(asoc->peer.port);
+	af = sctp_get_af_specific(to.sa.sa_family);
+	af->to_sk_daddr(&to, sk); 
+
+	timeo = sock_sndtimeo(sk, sk->socket->file->f_flags & O_NONBLOCK);
+	err = sctp_wait_for_connect(asoc, &timeo);
+
+out_unlock:
+	sctp_release_sock(sk);
+
+	return err;
+}
+
+/* FIXME: Write comments. */
+SCTP_STATIC int sctp_disconnect(struct sock *sk, int flags)
+{
+	return -EOPNOTSUPP; /* STUB */
+}
+
+/* 4.1.4 accept() - TCP Style Syntax
+ *
+ * Applications use accept() call to remove an established SCTP
+ * association from the accept queue of the endpoint.  A new socket
+ * descriptor will be returned from accept() to represent the newly
+ * formed association.
+ */
+SCTP_STATIC struct sock *sctp_accept(struct sock *sk, int flags, int *err)
+{
+	struct sctp_opt *sp;
+	struct sctp_endpoint *ep;
+	struct sock *newsk = NULL;
+	struct sctp_association *asoc;
+	long timeo;
+	int error = 0;
+
+	sctp_lock_sock(sk);
+
+	sp = sctp_sk(sk);
+	ep = sp->ep;
+
+	if (SCTP_SOCKET_TCP != sp->type) {
+		error = -EOPNOTSUPP;
+		goto out;
+	}
+
+	if (SCTP_SS_LISTENING != sk->state) {
+		error = -EINVAL;
+		goto out;
+	}
+
+	timeo = sock_rcvtimeo(sk, sk->socket->file->f_flags & O_NONBLOCK);
+
+	error = sctp_wait_for_accept(sk, timeo);
+	if (error)
+		goto out;
+
+	/* We treat the list of associations on the endpoint as the accept
+	 * queue and pick the first association on the list.
+	 */
+	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
+
+	newsk = sp->pf->create_accept_sk(sk, asoc);
+	if (!newsk) {
+		error = -ENOMEM;
+		goto out;
+	}
+
+	/* Populate the fields of the newsk from the oldsk and migrate the
+	 * asoc to the newsk.
+	 */
+	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
+
+out:
+	sctp_release_sock(sk);
+ 	*err = error;
+	return newsk;
+}
+
+/* The SCTP ioctl handler. */
+SCTP_STATIC int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
+{
+	return -ENOIOCTLCMD;
+}
+
+/* This is the function which gets called during socket creation to
+ * initialized the SCTP-specific portion of the sock.
+ * The sock structure should already be zero-filled memory.
+ */
+SCTP_STATIC int sctp_init_sock(struct sock *sk)
+{
+	struct sctp_endpoint *ep;
+	struct sctp_protocol *proto;
+	struct sctp_opt *sp;
+
+	SCTP_DEBUG_PRINTK("sctp_init_sock(sk: %p)\n", sk);
+
+	proto = sctp_get_protocol();
+
+	sp = sctp_sk(sk);
+
+	/* Initialize the SCTP per socket area.  */
+	switch (sk->type) {
+	case SOCK_SEQPACKET:
+		sp->type = SCTP_SOCKET_UDP;
+		break;
+	case SOCK_STREAM:
+		sp->type = SCTP_SOCKET_TCP;
+		break;
+	default:
+		return -ESOCKTNOSUPPORT;
+	}
+
+	/* FIXME:  The next draft (04) of the SCTP Sockets Extensions
+	 * should include a socket option for manipulating these
+	 * message parameters (and a few others).
+	 */
+	sp->default_stream = 0;
+	sp->default_ppid = 0;
+
+	/* Initialize default setup parameters. These parameters
+	 * can be modified with the SCTP_INITMSG socket option or
+	 * overridden by the SCTP_INIT CMSG.
+	 */
+	sp->initmsg.sinit_num_ostreams   = proto->max_outstreams;
+	sp->initmsg.sinit_max_instreams  = proto->max_instreams;
+	sp->initmsg.sinit_max_attempts   = proto->max_retrans_init;
+	sp->initmsg.sinit_max_init_timeo = proto->rto_max / HZ;
+
+	/* Initialize default RTO related parameters.  These parameters can
+	 * be modified for with the SCTP_RTOINFO socket option.
+	 * FIXME: These are not used yet.
+	 */
+	sp->rtoinfo.srto_initial = proto->rto_initial;
+	sp->rtoinfo.srto_max     = proto->rto_max;
+	sp->rtoinfo.srto_min     = proto->rto_min;
+
+	/* Initialize default event subscriptions.
+	 * the struct sock is initialized to zero, so only
+	 * enable the events needed.  By default, UDP-style
+	 * sockets enable io and association change notifications.
+	 */
+	if (SCTP_SOCKET_UDP == sp->type) {
+		sp->subscribe.sctp_data_io_event     = 1;
+		sp->subscribe.sctp_association_event = 1;
+	}
+
+	/* Default Peer Address Parameters.  These defaults can
+	 * be modified via SCTP_SET_PEER_ADDR_PARAMS
+	 */
+	sp->paddrparam.spp_hbinterval = proto->hb_interval / HZ;
+	sp->paddrparam.spp_pathmaxrxt = proto->max_retrans_path;
+
+	/* If enabled no SCTP message fragmentation will be performed.
+	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
+	 */
+	sp->disable_fragments = 0;
+
+	/* Turn on/off any Nagle-like algorithm.  */
+	sp->nodelay           = 1;
+
+	/* Auto-close idle associations after the configured
+	 * number of seconds.  A value of 0 disables this
+	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
+	 * for UDP-style sockets only.
+	 */
+	sp->autoclose         = 0;
+	sp->pf = sctp_get_pf_specific(sk->family);
+
+	/* Control variables for partial data delivery. */
+	sp->pd_mode           = 0;
+	skb_queue_head_init(&sp->pd_lobby);
+
+	/* Create a per socket endpoint structure.  Even if we
+	 * change the data structure relationships, this may still
+	 * be useful for storing pre-connect address information.
+	 */
+	ep = sctp_endpoint_new(sk, GFP_KERNEL);
+	if (!ep)
+		return -ENOMEM;
+
+	sp->ep = ep;
+	sp->hmac = NULL;
+
+	SCTP_DBG_OBJCNT_INC(sock);
+	return 0;
+}
+
+/* Cleanup any SCTP per socket resources.  */
+SCTP_STATIC int sctp_destroy_sock(struct sock *sk)
+{
+	struct sctp_endpoint *ep;
+
+	SCTP_DEBUG_PRINTK("sctp_destroy_sock(sk: %p)\n", sk);
+
+	/* Release our hold on the endpoint. */
+	ep = sctp_sk(sk)->ep;
+	sctp_endpoint_free(ep);
+
+	return 0;
+}
+
+/* API 4.1.7 shutdown() - TCP Style Syntax
+ *     int shutdown(int socket, int how);
+ *
+ *     sd      - the socket descriptor of the association to be closed.
+ *     how     - Specifies the type of shutdown.  The  values  are
+ *               as follows:
+ *               SHUT_RD
+ *                     Disables further receive operations. No SCTP
+ *                     protocol action is taken.
+ *               SHUT_WR
+ *                     Disables further send operations, and initiates
+ *                     the SCTP shutdown sequence.
+ *               SHUT_RDWR
+ *                     Disables further send  and  receive  operations
+ *                     and initiates the SCTP shutdown sequence.
+ */
+SCTP_STATIC void sctp_shutdown(struct sock *sk, int how)
+{
+	struct sctp_endpoint *ep;
+	struct sctp_association *asoc;
+
+	if (SCTP_SOCKET_TCP != sctp_sk(sk)->type)
+		return;
+
+	if (how & SEND_SHUTDOWN) {
+		ep = sctp_sk(sk)->ep;
+		if (!list_empty(&ep->asocs)) {
+			asoc = list_entry(ep->asocs.next,
+					  struct sctp_association, asocs);
+			sctp_primitive_SHUTDOWN(asoc, NULL);
+		}
+	}
+}
+
+/* 7.2.1 Association Status (SCTP_STATUS)
+
+ * Applications can retrieve current status information about an
+ * association, including association state, peer receiver window size,
+ * number of unacked data chunks, and number of data chunks pending
+ * receipt.  This information is read-only.
+ */
+static int sctp_getsockopt_sctp_status(struct sock *sk, int len, char *optval,
+				       int *optlen)
+{
+	struct sctp_status status;
+	struct sctp_association *asoc = NULL;
+	struct sctp_transport *transport;
+	sctp_assoc_t associd;
+	int retval = 0;
+
+	if (len != sizeof(status)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	if (copy_from_user(&status, optval, sizeof(status))) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	associd = status.sstat_assoc_id;
+	asoc = sctp_id2assoc(sk, associd);
+	if (!asoc) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	transport = asoc->peer.primary_path;
+
+	status.sstat_assoc_id = sctp_assoc2id(asoc);
+	status.sstat_state = asoc->state;
+	status.sstat_rwnd =  asoc->peer.rwnd;
+	status.sstat_unackdata = asoc->unack_data;
+	status.sstat_penddata = asoc->peer.tsn_map.pending_data;
+	status.sstat_instrms = asoc->c.sinit_max_instreams;
+	status.sstat_outstrms = asoc->c.sinit_num_ostreams;
+	status.sstat_fragmentation_point = asoc->frag_point;
+	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
+	memcpy(&status.sstat_primary.spinfo_address,
+	       &(transport->ipaddr), sizeof(union sctp_addr));
+	status.sstat_primary.spinfo_state = transport->active;
+	status.sstat_primary.spinfo_cwnd = transport->cwnd;
+	status.sstat_primary.spinfo_srtt = transport->srtt;
+	status.sstat_primary.spinfo_rto = transport->rto;
+	status.sstat_primary.spinfo_mtu = transport->pmtu;
+
+	if (put_user(len, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	SCTP_DEBUG_PRINTK("sctp_getsockopt_sctp_status(%d): %d %d %p\n",
+			  len, status.sstat_state, status.sstat_rwnd,
+			  status.sstat_assoc_id);
+
+	if (copy_to_user(optval, &status, len)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+out:
+	return (retval);
+}
+
+static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
+						    char *optval, int *optlen)
+{
+	int val;
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+	val = (sctp_sk(sk)->disable_fragments == 1);
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+	return 0;
+}
+
+static int sctp_getsockopt_set_events(struct sock *sk, int len, char *optval, int *optlen)
+{
+	if (len != sizeof(struct sctp_event_subscribe))
+		return -EINVAL;
+	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
+		return -EFAULT;
+	return 0;
+}
+
+static int sctp_getsockopt_autoclose(struct sock *sk, int len, char *optval, int *optlen)
+{
+	/* Applicable to UDP-style socket only */
+	if (SCTP_SOCKET_TCP == sctp_sk(sk)->type)
+		return -EOPNOTSUPP;
+	if (len != sizeof(int))
+		return -EINVAL;
+	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, len))
+		return -EFAULT;
+	return 0;
+}
+
+/* Helper routine to branch off an association to a new socket.  */
+SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
+				struct socket **sockp)
+{
+	struct sock *sk = asoc->base.sk;
+	struct socket *sock;
+	int err = 0;
+
+	/* An association cannot be branched off from an already peeled-off
+	 * socket, nor is this supported for tcp style sockets.
+	 */
+	if (SCTP_SOCKET_UDP != sctp_sk(sk)->type)
+		return -EINVAL;
+
+	/* Create a new socket.  */
+	err = sock_create(sk->family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
+	if (err < 0)
+		return err;
+
+	/* Populate the fields of the newsk from the oldsk and migrate the
+	 * asoc to the newsk.
+	 */
+	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
+	*sockp = sock;
+
+	return err;
+}
+
+static int sctp_getsockopt_peeloff(struct sock *sk, int len, char *optval, int *optlen)
+{
+	sctp_peeloff_arg_t peeloff;
+	struct socket *newsock;
+	int retval = 0;
+	struct sctp_association *asoc;
+
+	if (len != sizeof(sctp_peeloff_arg_t))
+		return -EINVAL;
+	if (copy_from_user(&peeloff, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, peeloff.associd);
+	if (!asoc) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p\n", __FUNCTION__, sk, asoc);
+
+	retval = sctp_do_peeloff(asoc, &newsock);
+	if (retval < 0)
+		goto out;
+
+	/* Map the socket to an unused fd that can be returned to the user.  */
+	retval = sock_map_fd(newsock);
+	if (retval < 0) {
+		sock_release(newsock);
+		goto out;
+	}
+
+	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p newsk: %p sd: %d\n",
+			  __FUNCTION__, sk, asoc, newsock->sk, retval);
+
+	/* Return the fd mapped to the new socket.  */
+	peeloff.sd = retval;
+	if (copy_to_user(optval, &peeloff, len))
+		retval = -EFAULT;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
+						char *optval, int *optlen)
+{
+	struct sctp_paddrparams params;
+	struct sctp_association *asoc;
+	union sctp_addr *addr;
+	struct sctp_transport *trans;
+
+	if (len != sizeof(struct sctp_paddrparams))
+		return -EINVAL;
+	if (copy_from_user(&params, optval, *optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	addr = (union sctp_addr *) &(params.spp_address);
+
+	trans = sctp_assoc_lookup_paddr(asoc, addr);
+	if (!trans)
+		return -ENOENT;
+
+	/* The value of the heartbeat interval, in milliseconds. A value of 0,
+	 * when modifying the parameter, specifies that the heartbeat on this
+	 * address should be disabled.
+	 */
+	if (!trans->hb_allowed)
+		params.spp_hbinterval = 0;
+	else
+		params.spp_hbinterval = trans->hb_interval * 1000 / HZ;
+
+	/* spp_pathmaxrxt contains the maximum number of retransmissions
+	 * before this address shall be considered unreachable.
+	 */
+	params.spp_pathmaxrxt = trans->error_threshold;
+
+	if (copy_to_user(optval, &params, len))
+		return -EFAULT;
+	*optlen = len;
+
+	return 0;
+}
+
+static int sctp_getsockopt_initmsg(struct sock *sk, int len, char *optval, int *optlen)
+{
+	if (len != sizeof(struct sctp_initmsg))
+		return -EINVAL;
+	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
+		return -EFAULT;
+	return 0;
+}
+
+static int sctp_getsockopt_peer_addrs_num(struct sock *sk, int len,
+					char *optval, int *optlen)
+{
+	sctp_assoc_t id;
+	struct sctp_association *asoc;
+	struct list_head *pos;
+	int cnt = 0;
+
+	if (len != sizeof(sctp_assoc_t))
+		return -EINVAL;
+
+	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
+		return -EFAULT;
+
+	/*
+	 *  For UDP-style sockets, id specifies the association to query.
+	 */
+	asoc = sctp_id2assoc(sk, id);
+	if (!asoc)
+		return -EINVAL;
+
+	list_for_each(pos, &asoc->peer.transport_addr_list) {
+		cnt ++;
+	}
+	if (copy_to_user(optval, &cnt, sizeof(int)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
+				char *optval, int *optlen)
+{
+	struct sctp_association *asoc;
+	struct list_head *pos;
+	int cnt = 0;
+	struct sctp_getaddrs getaddrs;
+	struct sctp_transport *from;
+	struct sockaddr_storage *to;
+
+	if (len != sizeof(struct sctp_getaddrs))
+		return -EINVAL;
+
+	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
+		return -EFAULT;
+
+	if (getaddrs.addr_num <= 0) return -EINVAL;
+	/*
+	 *  For UDP-style sockets, id specifies the association to query.
+	 */
+	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	to = getaddrs.addrs;
+	list_for_each(pos, &asoc->peer.transport_addr_list) {
+		from = list_entry(pos, struct sctp_transport, transports);
+		if (copy_to_user(to, &from->ipaddr, sizeof(from->ipaddr)))
+			return -EFAULT;
+		to ++;
+		cnt ++;
+		if (cnt >= getaddrs.addr_num) break;
+	}
+	getaddrs.addr_num = cnt;
+	if (copy_to_user(optval, &getaddrs, sizeof(struct sctp_getaddrs)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_getsockopt_local_addrs_num(struct sock *sk, int len,
+						char *optval, int *optlen)
+{
+	sctp_assoc_t id;
+	sctp_bind_addr_t *bp;
+	struct sctp_association *asoc;
+	struct list_head *pos;
+	int cnt = 0;
+
+	if (len != sizeof(sctp_assoc_t))
+		return -EINVAL;
+
+	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
+		return -EFAULT;
+
+	/*
+	 *  For UDP-style sockets, id specifies the association to query.
+	 *  If the id field is set to the value '0' then the locally bound
+	 *  addresses are returned without regard to any particular
+	 *  association.
+	 */
+	if (0 == id) {
+		bp = &sctp_sk(sk)->ep->base.bind_addr;
+	} else {
+		asoc = sctp_id2assoc(sk, id);
+		if (!asoc)
+			return -EINVAL;
+		bp = &asoc->base.bind_addr;
+	}
+
+	list_for_each(pos, &bp->address_list) {
+		cnt ++;
+	}
+	if (copy_to_user(optval, &cnt, sizeof(int)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
+					char *optval, int *optlen)
+{
+	sctp_bind_addr_t *bp;
+	struct sctp_association *asoc;
+	struct list_head *pos;
+	int cnt = 0;
+	struct sctp_getaddrs getaddrs;
+	struct sockaddr_storage_list *from;
+	struct sockaddr_storage *to;
+
+	if (len != sizeof(struct sctp_getaddrs))
+		return -EINVAL;
+
+	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
+		return -EFAULT;
+
+	if (getaddrs.addr_num <= 0) return -EINVAL;
+	/*
+	 *  For UDP-style sockets, id specifies the association to query.
+	 *  If the id field is set to the value '0' then the locally bound
+	 *  addresses are returned without regard to any particular
+	 *  association.
+	 */
+	if (0 == getaddrs.assoc_id) {
+		bp = &sctp_sk(sk)->ep->base.bind_addr;
+	} else {
+		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
+		if (!asoc)
+			return -EINVAL;
+		bp = &asoc->base.bind_addr;
+	}
+
+	to = getaddrs.addrs;
+	list_for_each(pos, &bp->address_list) {
+		from = list_entry(pos,
+				struct sockaddr_storage_list,
+				list);
+		if (copy_to_user(to, &from->a, sizeof(from->a)))
+			return -EFAULT;
+		to ++;
+		cnt ++;
+		if (cnt >= getaddrs.addr_num) break;
+	}
+	getaddrs.addr_num = cnt;
+	if (copy_to_user(optval, &getaddrs, sizeof(struct sctp_getaddrs)))
+		return -EFAULT;
+
+	return 0;
+}
+
+/* 7.1.10 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
+ *
+ * Requests that the local SCTP stack use the enclosed peer address as
+ * the association primary.  The enclosed address must be one of the
+ * association peer's addresses.
+ */
+static int sctp_getsockopt_peer_prim(struct sock *sk, int len,
+				char *optval, int *optlen)
+{
+	struct sctp_setpeerprim prim;
+	struct sctp_association *asoc;
+
+	if (len != sizeof(struct sctp_setpeerprim))
+		return -EINVAL;
+
+	if (copy_from_user(&prim, optval, sizeof(struct sctp_setpeerprim)))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	if (!asoc->peer.primary_path)
+		return -ENOTCONN;
+
+	memcpy(&prim.sspp_addr, &asoc->peer.primary_path->ipaddr,
+	       sizeof(union sctp_addr));
+
+	if (copy_to_user(optval, &prim, sizeof(struct sctp_setpeerprim)))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ *
+ * 7.1.15 Set default send parameters (SET_DEFAULT_SEND_PARAM)
+ *
+ *   Applications that wish to use the sendto() system call may wish to
+ *   specify a default set of parameters that would normally be supplied
+ *   through the inclusion of ancillary data.  This socket option allows
+ *   such an application to set the default sctp_sndrcvinfo structure.
+ *   The application that wishes to use this socket option simply passes
+ *   in to this call the sctp_sndrcvinfo structure defined in Section
+ *   5.2.2) The input parameters accepted by this call include
+ *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
+ *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
+ *   to this call if the caller is using the UDP model.
+ *
+ *   For getsockopt, it get the default sctp_sndrcvinfo structure.
+ */
+static int sctp_getsockopt_default_send_param(struct sock *sk,
+					int len, char *optval, int *optlen)
+{
+	struct sctp_sndrcvinfo info;
+	struct sctp_association *asoc;
+
+	if (len != sizeof(struct sctp_sndrcvinfo))
+		return -EINVAL;
+	if (copy_from_user(&info, optval, sizeof(struct sctp_sndrcvinfo)))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	info.sinfo_stream = asoc->defaults.stream;
+	info.sinfo_flags = asoc->defaults.flags;
+	info.sinfo_ppid = asoc->defaults.ppid;
+	info.sinfo_context = asoc->defaults.context;
+	info.sinfo_timetolive = asoc->defaults.timetolive;
+
+	if (copy_to_user(optval, &info, sizeof(struct sctp_sndrcvinfo)))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ *
+ * 7.1.5 SCTP_NODELAY
+ *
+ * Turn on/off any Nagle-like algorithm.  This means that packets are
+ * generally sent as soon as possible and no unnecessary delays are
+ * introduced, at the cost of more packets in the network.  Expects an
+ * integer boolean flag.
+ */
+
+static int sctp_getsockopt_nodelay(struct sock *sk, int len,
+					char *optval, int *optlen)
+{
+	__u8 val;
+
+	if (len < sizeof(__u8))
+		return -EINVAL;
+
+	len = sizeof(__u8);
+	val = (sctp_sk(sk)->nodelay == 1);
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+	return 0;
+}
+
+SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
+				char *optval, int *optlen)
+{
+	int retval = 0;
+	int len;
+
+	SCTP_DEBUG_PRINTK("sctp_getsockopt(sk: %p, ...)\n", sk);
+
+	/* I can hardly begin to describe how wrong this is.  This is
+	 * so broken as to be worse than useless.  The API draft
+	 * REALLY is NOT helpful here...  I am not convinced that the
+	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
+	 * are at all well-founded.
+	 */
+	if (level != SOL_SCTP) {
+		struct sctp_af *af = sctp_sk(sk)->pf->af;
+
+		retval = af->getsockopt(sk, level, optname, optval, optlen);
+		return retval;
+	}
+
+	if (get_user(len, optlen))
+		return -EFAULT;
+
+	sctp_lock_sock(sk);
+
+	switch (optname) {
+	case SCTP_STATUS:
+		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
+		break;
+	case SCTP_DISABLE_FRAGMENTS:
+		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
+							   optlen);
+		break;
+	case SCTP_SET_EVENTS:
+		retval = sctp_getsockopt_set_events(sk, len, optval, optlen);
+		break;
+	case SCTP_AUTOCLOSE:
+		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
+		break;
+	case SCTP_SOCKOPT_PEELOFF:
+		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
+		break;
+	case SCTP_GET_PEER_ADDR_PARAMS:
+		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
+							  optlen);
+		break;
+	case SCTP_INITMSG:
+		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
+		break;
+	case SCTP_GET_PEER_ADDRS_NUM:
+		retval = sctp_getsockopt_peer_addrs_num(sk, len, optval,
+							optlen);
+		break;
+	case SCTP_GET_LOCAL_ADDRS_NUM:
+		retval = sctp_getsockopt_local_addrs_num(sk, len, optval,
+							 optlen);
+		break;
+	case SCTP_GET_PEER_ADDRS:
+		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
+						    optlen);
+		break;
+	case SCTP_GET_LOCAL_ADDRS:
+		retval = sctp_getsockopt_local_addrs(sk, len, optval,
+						     optlen);
+		break;
+	case SCTP_SET_DEFAULT_SEND_PARAM:
+		retval = sctp_getsockopt_default_send_param(sk, len,
+							    optval, optlen);
+		break;
+	case SCTP_SET_PEER_PRIMARY_ADDR:
+		retval = sctp_getsockopt_peer_prim(sk, len, optval, optlen);
+		break;
+	case SCTP_NODELAY:
+		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
+		break;
+	default:
+		retval = -ENOPROTOOPT;
+		break;
+	};
+
+	sctp_release_sock(sk);
+	return retval;
+}
+
+static void sctp_hash(struct sock *sk)
+{
+	/* STUB */
+}
+
+static void sctp_unhash(struct sock *sk)
+{
+	/* STUB */
+}
+
+/* Check if port is acceptable.  Possibly find first available port.
+ *
+ * The port hash table (contained in the 'global' SCTP protocol storage
+ * returned by struct sctp_protocol *sctp_get_protocol()). The hash
+ * table is an array of 4096 lists (sctp_bind_hashbucket_t). Each
+ * list (the list number is the port number hashed out, so as you
+ * would expect from a hash function, all the ports in a given list have
+ * such a number that hashes out to the same list number; you were
+ * expecting that, right?); so each list has a set of ports, with a
+ * link to the socket (struct sock) that uses it, the port number and
+ * a fastreuse flag (FIXME: NPI ipg).
+ */
+static sctp_bind_bucket_t *sctp_bucket_create(sctp_bind_hashbucket_t *head,
+					      unsigned short snum);
+static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
+{
+	sctp_bind_hashbucket_t *head; /* hash list */
+	sctp_bind_bucket_t *pp; /* hash list port iterator */
+	struct sctp_protocol *sctp = sctp_get_protocol();
+	unsigned short snum;
+	int ret;
+
+	/* NOTE:  Remember to put this back to net order. */
+	addr->v4.sin_port = ntohs(addr->v4.sin_port);
+	snum = addr->v4.sin_port;
+
+	SCTP_DEBUG_PRINTK("sctp_get_port() begins, snum=%d\n", snum);
+
+	sctp_local_bh_disable();
+
+	if (snum == 0) {
+		/* Search for an available port.
+		 *
+		 * 'sctp->port_rover' was the last port assigned, so
+		 * we start to search from 'sctp->port_rover +
+		 * 1'. What we do is first check if port 'rover' is
+		 * already in the hash table; if not, we use that; if
+		 * it is, we try next.
+		 */
+		int low = sysctl_local_port_range[0];
+		int high = sysctl_local_port_range[1];
+		int remaining = (high - low) + 1;
+		int rover;
+		int index;
+
+		sctp_spin_lock(&sctp->port_alloc_lock);
+		rover = sctp->port_rover;
+		do {
+			rover++;
+			if ((rover < low) || (rover > high))
+				rover = low;
+			index = sctp_phashfn(rover);
+			head = &sctp->port_hashtable[index];
+			sctp_spin_lock(&head->lock);
+			for (pp = head->chain; pp; pp = pp->next)
+				if (pp->port == rover)
+					goto next;
+			break;
+		next:
+			sctp_spin_unlock(&head->lock);
+		} while (--remaining > 0);
+		sctp->port_rover = rover;
+		sctp_spin_unlock(&sctp->port_alloc_lock);
+
+		/* Exhausted local port range during search? */
+		ret = 1;
+		if (remaining <= 0)
+			goto fail;
+
+		/* OK, here is the one we will use.  HEAD (the port
+		 * hash table list entry) is non-NULL and we hold it's
+		 * mutex.
+		 */
+		snum = rover;
+		pp = NULL;
+	} else {
+		/* We are given an specific port number; we verify
+		 * that it is not being used. If it is used, we will
+		 * exahust the search in the hash list corresponding
+		 * to the port number (snum) - we detect that with the
+		 * port iterator, pp being NULL.
+		 */
+		head = &sctp->port_hashtable[sctp_phashfn(snum)];
+		sctp_spin_lock(&head->lock);
+		for (pp = head->chain; pp; pp = pp->next) {
+			if (pp->port == snum)
+				break;
+		}
+	}
+
+
+	if (pp && pp->sk) {
+		/* We had a port hash table hit - there is an
+		 * available port (pp != NULL) and it is being
+		 * used by other socket (pp->sk != NULL); that other
+		 * socket is going to be sk2.
+		 */
+		int sk_reuse = sk->reuse;
+		struct sock *sk2 = pp->sk;
+
+		SCTP_DEBUG_PRINTK("sctp_get_port() found a "
+				  "possible match\n");
+		if (pp->fastreuse != 0 && sk->reuse != 0)
+			goto success;
+
+		/* Run through the list of sockets bound to the port
+		 * (pp->port) [via the pointers bind_next and
+		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
+		 * we get the endpoint they describe and run through
+		 * the endpoint's list of IP (v4 or v6) addresses,
+		 * comparing each of the addresses with the address of
+		 * the socket sk. If we find a match, then that means
+		 * that this port/socket (sk) combination are already
+		 * in an endpoint.
+		 */
+		for ( ; sk2 != NULL; sk2 = sk2->bind_next) {
+			struct sctp_endpoint *ep2;
+			ep2 = sctp_sk(sk2)->ep;
+
+			if (sk_reuse && sk2->reuse)
+				continue;
+
+			if (sctp_bind_addr_match(&ep2->base.bind_addr, addr,
+						 sctp_sk(sk)))
+				goto found;
+		}
+
+	found:
+		/* If we found a conflict, fail.  */
+		if (sk2 != NULL) {
+			ret = (long) sk2;
+			goto fail_unlock;
+		}
+		SCTP_DEBUG_PRINTK("sctp_get_port(): Found a match\n");
+	}
+
+	/* If there was a hash table miss, create a new port.  */
+	ret = 1;
+
+	if (!pp && !(pp = sctp_bucket_create(head, snum)))
+		goto fail_unlock;
+
+	/* In either case (hit or miss), make sure fastreuse is 1 only
+	 * if sk->reuse is too (that is, if the caller requested
+	 * SO_REUSEADDR on this socket -sk-).
+	 */
+	if (!pp->sk)
+		pp->fastreuse = sk->reuse ? 1 : 0;
+	else if (pp->fastreuse && sk->reuse == 0)
+		pp->fastreuse = 0;
+
+	/* We are set, so fill up all the data in the hash table
+	 * entry, tie the socket list information with the rest of the
+	 * sockets FIXME: Blurry, NPI (ipg).
+	 */
+success:
+	(sk)->num = snum;
+	if (sk->prev == NULL) {
+		if ((sk->bind_next = pp->sk) != NULL)
+			pp->sk->bind_pprev = &sk->bind_next;
+		pp->sk = sk;
+		sk->bind_pprev = &pp->sk;
+		sk->prev = (struct sock *) pp;
+	}
+	ret = 0;
+
+fail_unlock:
+	sctp_spin_unlock(&head->lock);
+
+fail:
+	sctp_local_bh_enable();
+
+	SCTP_DEBUG_PRINTK("sctp_get_port() ends, ret=%d\n", ret);
+	addr->v4.sin_port = htons(addr->v4.sin_port);
+	return ret;
+}
+
+/* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
+ * port is requested.
+ */
+static int sctp_get_port(struct sock *sk, unsigned short snum)
+{
+	long ret;
+	union sctp_addr addr;
+	struct sctp_af *af = sctp_sk(sk)->pf->af;
+
+	/* Set up a dummy address struct from the sk. */
+	af->from_sk(&addr, sk);
+	addr.v4.sin_port = htons(snum);
+
+	/* Note: sk->num gets filled in if ephemeral port request. */
+	ret = sctp_get_port_local(sk, &addr);
+
+	return (ret ? 1 : 0);
+}
+
+/*
+ * 3.1.3 listen() - UDP Style Syntax
+ *
+ *   By default, new associations are not accepted for UDP style sockets.
+ *   An application uses listen() to mark a socket as being able to
+ *   accept new associations.
+ */
+SCTP_STATIC int sctp_seqpacket_listen(struct sock *sk, int backlog)
+{
+	struct sctp_opt *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
+
+	/* Only UDP style sockets that are not peeled off are allowed to
+	 * listen().
+	 */
+	if (SCTP_SOCKET_UDP != sp->type)
+		return -EINVAL;
+
+	if (sk->state == SCTP_SS_LISTENING)
+		return 0;
+
+	/*
+	 * If a bind() or sctp_bindx() is not called prior to a listen()
+	 * call that allows new associations to be accepted, the system
+	 * picks an ephemeral port and will choose an address set equivalent
+	 * to binding with a wildcard address.
+	 *
+	 * This is not currently spelled out in the SCTP sockets
+	 * extensions draft, but follows the practice as seen in TCP
+	 * sockets.
+	 */
+	if (!ep->base.bind_addr.port) {
+		if (sctp_autobind(sk))
+			return -EAGAIN;
+	}
+	sk->state = SCTP_SS_LISTENING;
+	sctp_hash_endpoint(ep);
+	return 0;
+}
+
+/*
+ * 4.1.3 listen() - TCP Style Syntax
+ *
+ *   Applications uses listen() to ready the SCTP endpoint for accepting
+ *   inbound associations.
+ */
+SCTP_STATIC int sctp_stream_listen(struct sock *sk, int backlog)
+{
+	struct sctp_opt *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
+
+	if (sk->state == SCTP_SS_LISTENING)
+		return 0;
+
+	/*
+	 * If a bind() or sctp_bindx() is not called prior to a listen()
+	 * call that allows new associations to be accepted, the system
+	 * picks an ephemeral port and will choose an address set equivalent
+	 * to binding with a wildcard address.
+	 *
+	 * This is not currently spelled out in the SCTP sockets
+	 * extensions draft, but follows the practice as seen in TCP
+	 * sockets.
+	 */
+	if (!ep->base.bind_addr.port) {
+		if (sctp_autobind(sk))
+			return -EAGAIN;
+	}
+	sk->state = SCTP_SS_LISTENING;
+	sk->max_ack_backlog = backlog;
+	sctp_hash_endpoint(ep);
+	return 0;
+}
+
+/*
+ *  Move a socket to LISTENING state.
+ */
+int sctp_inet_listen(struct socket *sock, int backlog)
+{
+	struct sock *sk = sock->sk;
+	struct crypto_tfm *tfm=NULL;
+	int err = -EINVAL;
+
+	if (unlikely(backlog < 0))
+		goto out;
+
+	sctp_lock_sock(sk);
+
+	if (sock->state != SS_UNCONNECTED)
+		goto out;
+
+	/* Allocate HMAC for generating cookie. */
+	if (sctp_hmac_alg) {
+		tfm = sctp_crypto_alloc_tfm(sctp_hmac_alg, 0);
+		if (!tfm) {
+			err = -ENOSYS;
+			goto out;
+		}
+	}
+
+	switch (sock->type) {
+	case SOCK_SEQPACKET:
+		err = sctp_seqpacket_listen(sk, backlog);
+		break;
+	case SOCK_STREAM:
+		err = sctp_stream_listen(sk, backlog);
+		break;
+	default:
+		break;
+	};
+	if (err)
+		goto cleanup;
+
+	/* Store away the transform reference. */
+	sctp_sk(sk)->hmac = tfm;
+out:
+	sctp_release_sock(sk);
+	return err;
+cleanup:
+	if (tfm)
+		sctp_crypto_free_tfm(tfm);
+	goto out;
+}
+
+/*
+ * This function is done by modeling the current datagram_poll() and the
+ * tcp_poll().  Note that, based on these implementations, we don't
+ * lock the socket in this function, even though it seems that,
+ * ideally, locking or some other mechanisms can be used to ensure
+ * the integrity of the counters (sndbuf and wmem_queued) used
+ * in this place.  We assume that we don't need locks either until proven
+ * otherwise.
+ *
+ * Another thing to note is that we include the Async I/O support
+ * here, again, by modeling the current TCP/UDP code.  We don't have
+ * a good way to test with it yet.
+ */
+unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	unsigned int mask;
+
+	poll_wait(file, sk->sleep, wait);
+	mask = 0;
+
+	/* Is there any exceptional events?  */
+	if (sk->err || !skb_queue_empty(&sk->error_queue))
+		mask |= POLLERR;
+	if (sk->shutdown == SHUTDOWN_MASK)
+		mask |= POLLHUP;
+
+	/* Is it readable?  Reconsider this code with TCP-style support.  */
+	if (!skb_queue_empty(&sk->receive_queue) ||
+	    (sk->shutdown & RCV_SHUTDOWN))
+		mask |= POLLIN | POLLRDNORM;
+
+	/*
+	 * FIXME: We need to set SCTP_SS_DISCONNECTING for TCP-style and
+	 * peeled off sockets.  Additionally, TCP-style needs to consider
+	 * other establishment conditions.
+	 */
+	if (SCTP_SOCKET_UDP != sctp_sk(sk)->type) {
+		/* The association is going away.  */
+		if (SCTP_SS_DISCONNECTING == sk->state)
+			mask |= POLLHUP;
+		/* The association is either gone or not ready.  */
+		if (SCTP_SS_CLOSED == sk->state)
+			return mask;
+	}
+
+	/* Is it writable?  */
+	if (sctp_writeable(sk)) {
+		mask |= POLLOUT | POLLWRNORM;
+	} else {
+		set_bit(SOCK_ASYNC_NOSPACE, &sk->socket->flags);
+		/*
+		 * Since the socket is not locked, the buffer
+		 * might be made available after the writeable check and
+		 * before the bit is set.  This could cause a lost I/O
+		 * signal.  tcp_poll() has a race breaker for this race
+		 * condition.  Based on their implementation, we put
+		 * in the following code to cover it as well.
+		 */
+		if (sctp_writeable(sk))
+			mask |= POLLOUT | POLLWRNORM;
+	}
+	return mask;
+}
+
+/********************************************************************
+ * 2nd Level Abstractions
+ ********************************************************************/
+
+static sctp_bind_bucket_t *sctp_bucket_create(sctp_bind_hashbucket_t *head, unsigned short snum)
+{
+	sctp_bind_bucket_t *pp;
+
+	SCTP_DEBUG_PRINTK( "sctp_bucket_create() begins, snum=%d\n", snum);
+	pp = kmalloc(sizeof(sctp_bind_bucket_t), GFP_ATOMIC);
+	if (pp) {
+		pp->port = snum;
+		pp->fastreuse = 0;
+		pp->sk = NULL;
+		if ((pp->next = head->chain) != NULL)
+			pp->next->pprev = &pp->next;
+		head->chain = pp;
+		pp->pprev = &head->chain;
+	}
+	SCTP_DEBUG_PRINTK("sctp_bucket_create() ends, pp=%p\n", pp);
+	return pp;
+}
+
+/* FIXME: Comments! */
+static __inline__ void __sctp_put_port(struct sock *sk)
+{
+	struct sctp_protocol *sctp_proto = sctp_get_protocol();
+	sctp_bind_hashbucket_t *head =
+		&sctp_proto->port_hashtable[sctp_phashfn((sk)->num)];
+	sctp_bind_bucket_t *pp;
+
+	sctp_spin_lock(&head->lock);
+	pp = (sctp_bind_bucket_t *) sk->prev;
+	if (sk->bind_next)
+		sk->bind_next->bind_pprev = sk->bind_pprev;
+	*(sk->bind_pprev) = sk->bind_next;
+	sk->prev = NULL;
+	(sk)->num = 0;
+	if (pp->sk) {
+		if (pp->next)
+			pp->next->pprev = pp->pprev;
+		*(pp->pprev) = pp->next;
+		kfree(pp);
+	}
+	sctp_spin_unlock(&head->lock);
+}
+
+void sctp_put_port(struct sock *sk)
+{
+	sctp_local_bh_disable();
+	__sctp_put_port(sk);
+	sctp_local_bh_enable();
+}
+
+/*
+ * The system picks an ephemeral port and choose an address set equivalent
+ * to binding with a wildcard address.
+ * One of those addresses will be the primary address for the association.
+ * This automatically enables the multihoming capability of SCTP.
+ */
+static int sctp_autobind(struct sock *sk)
+{
+	union sctp_addr autoaddr;
+	struct sctp_af *af;
+	unsigned short port;
+
+	/* Initialize a local sockaddr structure to INADDR_ANY. */
+	af = sctp_sk(sk)->pf->af;
+
+	port = htons((sk)->num);
+	af->inaddr_any(&autoaddr, port);
+
+	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
+}
+
+/* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
+ *
+ * From RFC 2292
+ * 4.2 The cmsghdr Structure *
+ *
+ * When ancillary data is sent or received, any number of ancillary data
+ * objects can be specified by the msg_control and msg_controllen members of
+ * the msghdr structure, because each object is preceded by
+ * a cmsghdr structure defining the object's length (the cmsg_len member).
+ * Historically Berkeley-derived implementations have passed only one object
+ * at a time, but this API allows multiple objects to be
+ * passed in a single call to sendmsg() or recvmsg(). The following example
+ * shows two ancillary data objects in a control buffer.
+ *
+ *   |<--------------------------- msg_controllen -------------------------->|
+ *   |                                                                       |
+ *
+ *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
+ *
+ *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
+ *   |                                   |                                   |
+ *
+ *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
+ *
+ *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
+ *   |                                |  |                                |  |
+ *
+ *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
+ *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
+ *
+ *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
+ *
+ *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
+ *    ^
+ *    |
+ *
+ * msg_control
+ * points here
+ */
+SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *msg,
+				  sctp_cmsgs_t *cmsgs)
+{
+	struct cmsghdr *cmsg;
+
+	for (cmsg = CMSG_FIRSTHDR(msg);
+	     cmsg != NULL;
+	     cmsg = CMSG_NXTHDR((struct msghdr*)msg, cmsg)) {
+		/* Check for minimum length.  The SCM code has this check.  */
+		if (cmsg->cmsg_len < sizeof(struct cmsghdr) ||
+		    (unsigned long)(((char*)cmsg - (char*)msg->msg_control)
+				    + cmsg->cmsg_len) > msg->msg_controllen) {
+			return -EINVAL;
+		}
+
+		/* Should we parse this header or ignore?  */
+		if (cmsg->cmsg_level != IPPROTO_SCTP)
+			continue;
+
+		/* Strictly check lengths following example in SCM code.  */
+		switch (cmsg->cmsg_type) {
+		case SCTP_INIT:
+			/* SCTP Socket API Extension
+			 * 5.2.1 SCTP Initiation Structure (SCTP_INIT)
+			 *
+			 * This cmsghdr structure provides information for
+			 * initializing new SCTP associations with sendmsg().
+			 * The SCTP_INITMSG socket option uses this same data
+			 * structure.  This structure is not used for
+			 * recvmsg().
+			 *
+			 * cmsg_level    cmsg_type      cmsg_data[]
+			 * ------------  ------------   ----------------------
+			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
+			 */
+			if (cmsg->cmsg_len !=
+			    CMSG_LEN(sizeof(struct sctp_initmsg)))
+				return -EINVAL;
+			cmsgs->init = (struct sctp_initmsg *)CMSG_DATA(cmsg);
+			break;
+
+		case SCTP_SNDRCV:
+			/* SCTP Socket API Extension
+			 * 5.2.2 SCTP Header Information Structure(SCTP_SNDRCV)
+			 *
+			 * This cmsghdr structure specifies SCTP options for
+			 * sendmsg() and describes SCTP header information
+			 * about a received message through recvmsg().
+			 *
+			 * cmsg_level    cmsg_type      cmsg_data[]
+			 * ------------  ------------   ----------------------
+			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
+			 */
+			if (cmsg->cmsg_len !=
+			    CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
+				return -EINVAL;
+
+			cmsgs->info =
+				(struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
+
+			/* Minimally, validate the sinfo_flags. */
+			if (cmsgs->info->sinfo_flags &
+			    ~(MSG_UNORDERED | MSG_ADDR_OVER |
+			      MSG_ABORT | MSG_EOF))
+				return -EINVAL;
+			break;
+
+		default:
+			return -EINVAL;
+		};
+	}
+	return 0;
+}
+
+/*
+ * Wait for a packet..
+ * Note: This function is the same function as in core/datagram.c
+ * with a few modifications to make lksctp work.
+ */
+static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p)
+{
+	int error;
+	DECLARE_WAITQUEUE(wait, current);
+
+	__set_current_state(TASK_INTERRUPTIBLE);
+	add_wait_queue_exclusive(sk->sleep, &wait);
+
+	/* Socket errors? */
+	error = sock_error(sk);
+	if (error)
+		goto out;
+
+	if (!skb_queue_empty(&sk->receive_queue))
+		goto ready;
+
+	/* Socket shut down?  */
+	if (sk->shutdown & RCV_SHUTDOWN)
+		goto out;
+
+	/* Sequenced packets can come disconnected.  If so we report the
+	 * problem.
+	 */
+	error = -ENOTCONN;
+
+	/* Is there a good reason to think that we may receive some data?  */
+	if ((list_empty(&sctp_sk(sk)->ep->asocs)) &&
+	    (sk->state != SCTP_SS_LISTENING))
+		goto out;
+
+	/* Handle signals.  */
+	if (signal_pending(current))
+		goto interrupted;
+
+	/* Let another process have a go.  Since we are going to sleep
+	 * anyway.  Note: This may cause odd behaviors if the message
+	 * does not fit in the user's buffer, but this seems to be the
+	 * only way to honor MSG_DONTWAIT realistically.
+	 */
+	sctp_release_sock(sk);
+	*timeo_p = schedule_timeout(*timeo_p);
+	sctp_lock_sock(sk);
+
+ready:
+	remove_wait_queue(sk->sleep, &wait);
+	__set_current_state(TASK_RUNNING);
+	return 0;
+
+interrupted:
+	error = sock_intr_errno(*timeo_p);
+
+out:
+	remove_wait_queue(sk->sleep, &wait);
+	__set_current_state(TASK_RUNNING);
+	*err = error;
+	return error;
+}
+
+/* Receive a datagram.
+ * Note: This is pretty much the same routine as in core/datagram.c
+ * with a few changes to make lksctp work.
+ */
+static struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
+					      int noblock, int *err)
+{
+	int error;
+	struct sk_buff *skb;
+	long timeo;
+
+	/* Caller is allowed not to check sk->err before calling.  */
+	error = sock_error(sk);
+	if (error)
+		goto no_packet;
+
+	timeo = sock_rcvtimeo(sk, noblock);
+
+	SCTP_DEBUG_PRINTK("Timeout: timeo: %ld, MAX: %ld.\n",
+			  timeo, MAX_SCHEDULE_TIMEOUT);
+
+	do {
+		/* Again only user level code calls this function,
+		 * so nothing interrupt level
+		 * will suddenly eat the receive_queue.
+		 *
+		 *  Look at current nfs client by the way...
+		 *  However, this function was corrent in any case. 8)
+		 */
+		if (flags & MSG_PEEK) {
+			unsigned long cpu_flags;
+
+			sctp_spin_lock_irqsave(&sk->receive_queue.lock,
+					       cpu_flags);
+			skb = skb_peek(&sk->receive_queue);
+			if (skb)
+				atomic_inc(&skb->users);
+			sctp_spin_unlock_irqrestore(&sk->receive_queue.lock,
+						    cpu_flags);
+		} else {
+			skb = skb_dequeue(&sk->receive_queue);
+		}
+
+		if (skb)
+			return skb;
+
+		if (sk->shutdown & RCV_SHUTDOWN)
+			break;
+
+		/* User doesn't want to wait.  */
+		error = -EAGAIN;
+		if (!timeo)
+			goto no_packet;
+	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
+
+	return NULL;
+
+no_packet:
+	*err = error;
+	return NULL;
+}
+
+/* Verify that this is a valid address. */
+static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
+				   int len)
+{
+	struct sctp_af *af;
+
+	/* Verify basic sockaddr. */
+	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
+	if (!af)
+		return -EINVAL;
+
+	/* Is this a valid SCTP address?  */
+	if (!af->addr_valid(addr))
+		return -EINVAL;
+
+	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
+		return -EINVAL;
+
+	return 0;
+}
+
+/* Get the sndbuf space available at the time on the association.  */
+static inline int sctp_wspace(struct sctp_association *asoc)
+{
+	struct sock *sk = asoc->base.sk;
+	int amt = 0;
+
+	amt = sk->sndbuf - asoc->sndbuf_used;
+	if (amt < 0)
+		amt = 0;
+	return amt;
+}
+
+/* Increment the used sndbuf space count of the corresponding association by
+ * the size of the outgoing data chunk.
+ * Also, set the skb destructor for sndbuf accounting later.
+ *
+ * Since it is always 1-1 between chunk and skb, and also a new skb is always
+ * allocated for chunk bundling in sctp_packet_transmit(), we can use the
+ * destructor in the data chunk skb for the purpose of the sndbuf space
+ * tracking.
+ */
+static inline void sctp_set_owner_w(sctp_chunk_t *chunk)
+{
+	struct sctp_association *asoc = chunk->asoc;
+	struct sock *sk = asoc->base.sk;
+
+	/* The sndbuf space is tracked per association.  */
+	sctp_association_hold(asoc);
+
+	chunk->skb->destructor = sctp_wfree;
+	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
+	*((sctp_chunk_t **)(chunk->skb->cb)) = chunk;
+
+	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk);
+	sk->wmem_queued += SCTP_DATA_SNDSIZE(chunk);
+}
+
+/* If sndbuf has changed, wake up per association sndbuf waiters.  */
+static void __sctp_write_space(struct sctp_association *asoc)
+{
+	struct sock *sk = asoc->base.sk;
+	struct socket *sock = sk->socket;
+
+	if ((sctp_wspace(asoc) > 0) && sock) {
+		if (waitqueue_active(&asoc->wait))
+			wake_up_interruptible(&asoc->wait);
+
+		if (sctp_writeable(sk)) {
+			if (sk->sleep && waitqueue_active(sk->sleep))
+				wake_up_interruptible(sk->sleep);
+
+			/* Note that we try to include the Async I/O support
+			 * here by modeling from the current TCP/UDP code.
+			 * We have not tested with it yet.
+			 */
+			if (sock->fasync_list &&
+			    !(sk->shutdown & SEND_SHUTDOWN))
+				sock_wake_async(sock, 2, POLL_OUT);
+		}
+	}
+}
+
+/* Do accounting for the sndbuf space.
+ * Decrement the used sndbuf space of the corresponding association by the
+ * data size which was just transmitted(freed).
+ */
+static void sctp_wfree(struct sk_buff *skb)
+{
+	struct sctp_association *asoc;
+	sctp_chunk_t *chunk;
+	struct sock *sk;
+
+	/* Get the saved chunk pointer.  */
+	chunk = *((sctp_chunk_t **)(skb->cb));
+	asoc = chunk->asoc;
+	sk = asoc->base.sk;
+	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk);
+	sk->wmem_queued -= SCTP_DATA_SNDSIZE(chunk);
+	__sctp_write_space(asoc);
+
+	sctp_association_put(asoc);
+}
+
+/* Helper function to wait for space in the sndbuf.  */
+static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
+				int msg_len)
+{
+	struct sock *sk = asoc->base.sk;
+	int err = 0;
+	long current_timeo = *timeo_p;
+	DECLARE_WAITQUEUE(wait, current);
+
+	SCTP_DEBUG_PRINTK("wait_for_sndbuf: asoc=%p, timeo=%ld, msg_len=%d\n",
+	                  asoc, (long)(*timeo_p), msg_len);
+
+	/* Wait on the association specific sndbuf space. */
+	add_wait_queue_exclusive(&asoc->wait, &wait);
+
+	/* Increment the association's refcnt.  */
+	sctp_association_hold(asoc);
+	for (;;) {
+		set_current_state(TASK_INTERRUPTIBLE);
+		if (!*timeo_p)
+			goto do_nonblock;
+		if (sk->err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
+		    asoc->base.dead)
+			goto do_error;
+		if (signal_pending(current))
+			goto do_interrupted;
+		if (msg_len <= sctp_wspace(asoc))
+			break;
+
+		/* Let another process have a go.  Since we are going
+		 * to sleep anyway.
+		 */
+		sctp_release_sock(sk);
+		current_timeo = schedule_timeout(current_timeo);
+		sctp_lock_sock(sk);
+
+		*timeo_p = current_timeo;
+	}
+
+out:
+	remove_wait_queue(&asoc->wait, &wait);
+
+	/* Release the association's refcnt.  */
+	sctp_association_put(asoc);
+
+	__set_current_state(TASK_RUNNING);
+	return err;
+
+do_error:
+	err = -EPIPE;
+	goto out;
+
+do_interrupted:
+	err = sock_intr_errno(*timeo_p);
+	goto out;
+
+do_nonblock:
+	err = -EAGAIN;
+	goto out;
+}
+
+/* If socket sndbuf has changed, wake up all per association waiters.  */
+void sctp_write_space(struct sock *sk)
+{
+	struct sctp_association *asoc;
+	struct list_head *pos;
+
+	/* Wake up the tasks in each wait queue.  */
+	list_for_each(pos, &((sctp_sk(sk))->ep->asocs)) {
+		asoc = list_entry(pos, struct sctp_association, asocs);
+		__sctp_write_space(asoc);
+	}
+}
+
+/* Is there any sndbuf space available on the socket?
+ *
+ * Note that wmem_queued is the sum of the send buffers on all of the
+ * associations on the same socket.  For a UDP-style socket with
+ * multiple associations, it is possible for it to be "unwriteable"
+ * prematurely.  I assume that this is acceptable because
+ * a premature "unwriteable" is better than an accidental "writeable" which
+ * would cause an unwanted block under certain circumstances.  For the 1-1
+ * UDP-style sockets or TCP-style sockets, this code should work.
+ *  - Daisy
+ */
+static int sctp_writeable(struct sock *sk)
+{
+	int amt = 0;
+
+	amt = sk->sndbuf - sk->wmem_queued;
+	if (amt < 0)
+		amt = 0;
+	return amt;
+}
+
+/* Wait for an association to go into ESTABLISHED state. If timeout is 0,
+ * returns immediately with EINPROGRESS.
+ */
+static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
+{
+	struct sock *sk = asoc->base.sk;
+	int err = 0;
+	long current_timeo = *timeo_p;
+	DECLARE_WAITQUEUE(wait, current);
+
+	SCTP_DEBUG_PRINTK("%s: asoc=%p, timeo=%ld\n", __FUNCTION__, asoc,
+			  (long)(*timeo_p));
+
+	add_wait_queue_exclusive(&asoc->wait, &wait);
+
+	/* Increment the association's refcnt.  */
+	sctp_association_hold(asoc);
+
+	for (;;) {
+		__set_current_state(TASK_INTERRUPTIBLE);
+		if (!*timeo_p)
+			goto do_nonblock;
+		if (sk->shutdown & RCV_SHUTDOWN)
+			break;
+		if (sk->err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
+		    asoc->base.dead)
+			goto do_error;
+		if (signal_pending(current))
+			goto do_interrupted;
+
+		if (asoc->state == SCTP_STATE_ESTABLISHED)
+			break;
+
+		/* Let another process have a go.  Since we are going
+		 * to sleep anyway.
+		 */
+		sctp_release_sock(sk);
+		current_timeo = schedule_timeout(current_timeo);
+		sctp_lock_sock(sk);
+
+		*timeo_p = current_timeo;
+	}
+
+out:
+	remove_wait_queue(&asoc->wait, &wait);
+
+	/* Release the association's refcnt.  */
+	sctp_association_put(asoc);
+
+	__set_current_state(TASK_RUNNING);
+
+	return err;
+
+do_error:
+	err = -ECONNREFUSED;
+	goto out;
+
+do_interrupted:
+	err = sock_intr_errno(*timeo_p);
+	goto out;
+
+do_nonblock:
+	err = -EINPROGRESS;
+	goto out;
+}
+
+static int sctp_wait_for_accept(struct sock *sk, long timeo)
+{
+	struct sctp_endpoint *ep;
+	int err = 0;
+	DECLARE_WAITQUEUE(wait, current);
+
+	ep = sctp_sk(sk)->ep;
+
+	add_wait_queue_exclusive(sk->sleep, &wait);
+
+	for (;;) {
+		__set_current_state(TASK_INTERRUPTIBLE);
+		if (list_empty(&ep->asocs)) {
+			sctp_release_sock(sk);
+			timeo = schedule_timeout(timeo);
+			sctp_lock_sock(sk);
+		}
+
+		err = -EINVAL;
+		if (sk->state != SCTP_SS_LISTENING)
+			break;
+
+		err = 0;
+		if (!list_empty(&ep->asocs))
+			break;
+
+		err = sock_intr_errno(timeo);
+		if (signal_pending(current))
+			break;
+
+		err = -EAGAIN;
+		if (!timeo)
+			break;
+	}
+
+	remove_wait_queue(sk->sleep, &wait);
+	__set_current_state(TASK_RUNNING);
+
+	return err;
+}
+
+/* Populate the fields of the newsk from the oldsk and migrate the assoc
+ * and its messages to the newsk.
+ */
+static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
+			      struct sctp_association *assoc,
+			      sctp_socket_type_t type)
+{
+	struct sctp_opt *oldsp = sctp_sk(oldsk);
+	struct sctp_opt *newsp = sctp_sk(newsk);
+	struct sctp_endpoint *newep = newsp->ep;
+	struct sk_buff *skb, *tmp;
+	struct sctp_ulpevent *event;
+
+	/* Migrate socket buffer sizes and all the socket level options to the
+	 * new socket.
+	 */
+	newsk->sndbuf = oldsk->sndbuf;
+	newsk->rcvbuf = oldsk->rcvbuf;
+	*newsp = *oldsp;
+
+	/* Restore the ep value that was overwritten with the above structure
+	 * copy.
+	 */
+	newsp->ep = newep;
+	newsp->hmac = NULL;
+
+	/* Move any messages in the old socket's receive queue that are for the
+	 * peeled off association to the new socket's receive queue.
+	 */
+	sctp_skb_for_each(skb, &oldsk->receive_queue, tmp) {
+		event = sctp_skb2event(skb);
+		if (event->event_asoc == assoc) {
+			__skb_unlink(skb, skb->list);
+			__skb_queue_tail(&newsk->receive_queue, skb);
+		}
+	}
+
+	/* Clean up any messages pending delivery due to partial
+	 * delivery.   Three cases:
+	 * 1) No partial deliver;  no work.
+	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
+	 * 3) Peeling off non-partial delivery; move pd_lobby to recieve_queue.
+	 */
+	skb_queue_head_init(&newsp->pd_lobby);
+	sctp_sk(newsk)->pd_mode = assoc->ulpq.pd_mode;;
+
+	if (sctp_sk(oldsk)->pd_mode) {
+		struct sk_buff_head *queue;
+
+		/* Decide which queue to move pd_lobby skbs to. */
+		if (assoc->ulpq.pd_mode) {
+			queue = &newsp->pd_lobby;
+		} else
+			queue = &newsk->receive_queue;
+
+		/* Walk through the pd_lobby, looking for skbs that
+		 * need moved to the new socket.
+		 */
+		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
+			event = sctp_skb2event(skb);
+			if (event->event_asoc == assoc) {
+				__skb_unlink(skb, skb->list);
+				__skb_queue_tail(queue, skb);
+			}
+		}
+
+		/* Clear up any skbs waiting for the partial
+		 * delivery to finish.
+		 */
+		if (assoc->ulpq.pd_mode)
+			sctp_clear_pd(oldsk);
+
+	}
+
+	/* Set the type of socket to indicate that it is peeled off from the
+	 * original UDP-style socket or created with the accept() call on a
+	 * TCP-style socket..
+	 */
+	newsp->type = type;
+
+	/* Migrate the association to the new socket. */
+	sctp_assoc_migrate(assoc, newsk);
+
+	newsk->state = SCTP_SS_ESTABLISHED;
+}
+
+/* This proto struct describes the ULP interface for SCTP.  */
+struct proto sctp_prot = {
+	.name        =	"SCTP",
+	.close       =	sctp_close,
+	.connect     =	sctp_connect,
+	.disconnect  =	sctp_disconnect,
+	.accept      =	sctp_accept,
+	.ioctl       =	sctp_ioctl,
+	.init        =	sctp_init_sock,
+	.destroy     =	sctp_destroy_sock,
+	.shutdown    =	sctp_shutdown,
+	.setsockopt  =	sctp_setsockopt,
+	.getsockopt  =	sctp_getsockopt,
+	.sendmsg     =	sctp_sendmsg,
+	.recvmsg     =	sctp_recvmsg,
+	.bind        =	sctp_bind,
+	.backlog_rcv =	sctp_backlog_rcv,
+	.hash        =	sctp_hash,
+	.unhash      =	sctp_unhash,
+	.get_port    =	sctp_get_port,
+};

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)