Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 9022 insertions, 0 deletions

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
new file mode 100644
index 000000000..8901bb7af
--- /dev/null
+++ b/net/sctp/socket.c
@@ -0,0 +1,9022 @@
+/* SCTP kernel implementation
+ * (C) Copyright IBM Corp. 2001, 2004
+ * Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * 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 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.
+ *
+ * This SCTP implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This SCTP implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ *    La Monte H.P. Yarroll <piggy@acm.org>
+ *    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>
+ *    Ryan Layer	    <rmlayer@us.ibm.com>
+ *    Anup Pemmaiah         <pemmaiah@cc.usu.edu>
+ *    Kevin Gao             <kevin.gao@intel.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <crypto/hash.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/wait.h>
+#include <linux/time.h>
+#include <linux/sched/signal.h>
+#include <linux/ip.h>
+#include <linux/capability.h>
+#include <linux/fcntl.h>
+#include <linux/poll.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/compat.h>
+#include <linux/rhashtable.h>
+
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/route.h>
+#include <net/ipv6.h>
+#include <net/inet_common.h>
+#include <net/busy_poll.h>
+
+#include <linux/socket.h> /* for sa_family_t */
+#include <linux/export.h>
+#include <net/sock.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+#include <net/sctp/stream_sched.h>
+
+/* Forward declarations for internal helper functions. */
+static bool sctp_writeable(struct sock *sk);
+static void sctp_wfree(struct sk_buff *skb);
+static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
+				size_t 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 void sctp_wait_for_close(struct sock *sk, long timeo);
+static void sctp_destruct_sock(struct sock *sk);
+static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
+					union sctp_addr *addr, int len);
+static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
+static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);
+static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);
+static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);
+static int sctp_send_asconf(struct sctp_association *asoc,
+			    struct sctp_chunk *chunk);
+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 *oldsk, struct sock *newsk,
+			      struct sctp_association *assoc,
+			      enum sctp_socket_type type);
+
+static unsigned long sctp_memory_pressure;
+static atomic_long_t sctp_memory_allocated;
+struct percpu_counter sctp_sockets_allocated;
+
+static void sctp_enter_memory_pressure(struct sock *sk)
+{
+	sctp_memory_pressure = 1;
+}
+
+
+/* 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;
+
+	return asoc->ep->sndbuf_policy ? sk->sk_sndbuf - asoc->sndbuf_used
+				       : sk_stream_wspace(sk);
+}
+
+/* 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(struct sctp_chunk *chunk)
+{
+	struct sctp_association *asoc = chunk->asoc;
+	struct sock *sk = asoc->base.sk;
+
+	/* The sndbuf space is tracked per association.  */
+	sctp_association_hold(asoc);
+
+	if (chunk->shkey)
+		sctp_auth_shkey_hold(chunk->shkey);
+
+	skb_set_owner_w(chunk->skb, sk);
+
+	chunk->skb->destructor = sctp_wfree;
+	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
+	skb_shinfo(chunk->skb)->destructor_arg = chunk;
+
+	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
+				sizeof(struct sk_buff) +
+				sizeof(struct sctp_chunk);
+
+	refcount_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
+	sk->sk_wmem_queued += chunk->skb->truesize;
+	sk_mem_charge(sk, chunk->skb->truesize);
+}
+
+static void sctp_clear_owner_w(struct sctp_chunk *chunk)
+{
+	skb_orphan(chunk->skb);
+}
+
+#define traverse_and_process()	\
+do {				\
+	msg = chunk->msg;	\
+	if (msg == prev_msg)	\
+		continue;	\
+	list_for_each_entry(c, &msg->chunks, frag_list) {	\
+		if ((clear && asoc->base.sk == c->skb->sk) ||	\
+		    (!clear && asoc->base.sk != c->skb->sk))	\
+			cb(c);	\
+	}			\
+	prev_msg = msg;		\
+} while (0)
+
+static void sctp_for_each_tx_datachunk(struct sctp_association *asoc,
+				       bool clear,
+				       void (*cb)(struct sctp_chunk *))
+
+{
+	struct sctp_datamsg *msg, *prev_msg = NULL;
+	struct sctp_outq *q = &asoc->outqueue;
+	struct sctp_chunk *chunk, *c;
+	struct sctp_transport *t;
+
+	list_for_each_entry(t, &asoc->peer.transport_addr_list, transports)
+		list_for_each_entry(chunk, &t->transmitted, transmitted_list)
+			traverse_and_process();
+
+	list_for_each_entry(chunk, &q->retransmit, transmitted_list)
+		traverse_and_process();
+
+	list_for_each_entry(chunk, &q->sacked, transmitted_list)
+		traverse_and_process();
+
+	list_for_each_entry(chunk, &q->abandoned, transmitted_list)
+		traverse_and_process();
+
+	list_for_each_entry(chunk, &q->out_chunk_list, list)
+		traverse_and_process();
+}
+
+static void sctp_for_each_rx_skb(struct sctp_association *asoc, struct sock *sk,
+				 void (*cb)(struct sk_buff *, struct sock *))
+
+{
+	struct sk_buff *skb, *tmp;
+
+	sctp_skb_for_each(skb, &asoc->ulpq.lobby, tmp)
+		cb(skb, sk);
+
+	sctp_skb_for_each(skb, &asoc->ulpq.reasm, tmp)
+		cb(skb, sk);
+
+	sctp_skb_for_each(skb, &asoc->ulpq.reasm_uo, tmp)
+		cb(skb, sk);
+}
+
+/* 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, sctp_sk(sk), NULL))
+		return -EINVAL;
+
+	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
+		return -EINVAL;
+
+	return 0;
+}
+
+/* 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_style(sk, UDP)) {
+		/* Return NULL if the socket state is not ESTABLISHED. It
+		 * could be a TCP-style listening socket or a socket which
+		 * hasn't yet called connect() to establish an association.
+		 */
+		if (!sctp_sstate(sk, ESTABLISHED) && !sctp_sstate(sk, CLOSING))
+			return NULL;
+
+		/* Get the first and the only association from the list. */
+		if (!list_empty(&sctp_sk(sk)->ep->asocs))
+			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
+					  struct sctp_association, asocs);
+		return asoc;
+	}
+
+	/* Otherwise this is a UDP-style socket. */
+	if (!id || (id == (sctp_assoc_t)-1))
+		return NULL;
+
+	spin_lock_bh(&sctp_assocs_id_lock);
+	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
+	if (asoc && (asoc->base.sk != sk || asoc->base.dead))
+		asoc = NULL;
+	spin_unlock_bh(&sctp_assocs_id_lock);
+
+	return asoc;
+}
+
+/* Look up the transport from an address and an assoc id. If both address and
+ * id are specified, the associations matching the address and the id should be
+ * the same.
+ */
+static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
+					      struct sockaddr_storage *addr,
+					      sctp_assoc_t id)
+{
+	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
+	struct sctp_af *af = sctp_get_af_specific(addr->ss_family);
+	union sctp_addr *laddr = (union sctp_addr *)addr;
+	struct sctp_transport *transport;
+
+	if (!af || sctp_verify_addr(sk, laddr, af->sockaddr_len))
+		return NULL;
+
+	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
+					       laddr,
+					       &transport);
+
+	if (!addr_asoc)
+		return NULL;
+
+	id_asoc = sctp_id2assoc(sk, id);
+	if (id_asoc && (id_asoc != addr_asoc))
+		return NULL;
+
+	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
+						(union sctp_addr *)addr);
+
+	return transport;
+}
+
+/* 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]),
+ *   addr_len - the size of the address structure.
+ */
+static int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
+{
+	int retval = 0;
+
+	lock_sock(sk);
+
+	pr_debug("%s: sk:%p, addr:%p, addr_len:%d\n", __func__, sk,
+		 addr, addr_len);
+
+	/* Disallow binding twice. */
+	if (!sctp_sk(sk)->ep->base.bind_addr.port)
+		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
+				      addr_len);
+	else
+		retval = -EINVAL;
+
+	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_sock *opt,
+					union sctp_addr *addr, int len)
+{
+	struct sctp_af *af;
+
+	/* Check minimum size.  */
+	if (len < sizeof (struct sockaddr))
+		return NULL;
+
+	if (!opt->pf->af_supported(addr->sa.sa_family, opt))
+		return NULL;
+
+	if (addr->sa.sa_family == AF_INET6) {
+		if (len < SIN6_LEN_RFC2133)
+			return NULL;
+		/* V4 mapped address are really of AF_INET family */
+		if (ipv6_addr_v4mapped(&addr->v6.sin6_addr) &&
+		    !opt->pf->af_supported(AF_INET, opt))
+			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;
+}
+
+static void sctp_auto_asconf_init(struct sctp_sock *sp)
+{
+	struct net *net = sock_net(&sp->inet.sk);
+
+	if (net->sctp.default_auto_asconf) {
+		spin_lock(&net->sctp.addr_wq_lock);
+		list_add_tail(&sp->auto_asconf_list, &net->sctp.auto_asconf_splist);
+		spin_unlock(&net->sctp.addr_wq_lock);
+		sp->do_auto_asconf = 1;
+	}
+}
+
+/* Bind a local address either to an endpoint or to an association.  */
+static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
+{
+	struct net *net = sock_net(sk);
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
+	struct sctp_bind_addr *bp = &ep->base.bind_addr;
+	struct sctp_af *af;
+	unsigned short snum;
+	int ret = 0;
+
+	/* Common sockaddr verification. */
+	af = sctp_sockaddr_af(sp, addr, len);
+	if (!af) {
+		pr_debug("%s: sk:%p, newaddr:%p, len:%d EINVAL\n",
+			 __func__, sk, addr, len);
+		return -EINVAL;
+	}
+
+	snum = ntohs(addr->v4.sin_port);
+
+	pr_debug("%s: sk:%p, new addr:%pISc, port:%d, new port:%d, len:%d\n",
+		 __func__, sk, &addr->sa, bp->port, snum, len);
+
+	/* PF specific bind() address verification. */
+	if (!sp->pf->bind_verify(sp, addr))
+		return -EADDRNOTAVAIL;
+
+	/* We must either be unbound, or bind to the same port.
+	 * It's OK to allow 0 ports if we are already bound.
+	 * We'll just inhert an already bound port in this case
+	 */
+	if (bp->port) {
+		if (!snum)
+			snum = bp->port;
+		else if (snum != bp->port) {
+			pr_debug("%s: new port %d doesn't match existing port "
+				 "%d\n", __func__, snum, bp->port);
+			return -EINVAL;
+		}
+	}
+
+	if (snum && snum < inet_prot_sock(net) &&
+	    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
+		return -EACCES;
+
+	/* See if the address matches any of the addresses we may have
+	 * already bound before checking against other endpoints.
+	 */
+	if (sctp_bind_addr_match(bp, addr, sp))
+		return -EINVAL;
+
+	/* Make sure we are allowed to bind here.
+	 * The function sctp_get_port_local() does duplicate address
+	 * detection.
+	 */
+	addr->v4.sin_port = htons(snum);
+	if ((ret = sctp_get_port_local(sk, addr))) {
+		return -EADDRINUSE;
+	}
+
+	/* Refresh ephemeral port.  */
+	if (!bp->port) {
+		bp->port = inet_sk(sk)->inet_num;
+		sctp_auto_asconf_init(sp);
+	}
+
+	/* Add the address to the bind address list.
+	 * Use GFP_ATOMIC since BHs will be disabled.
+	 */
+	ret = sctp_add_bind_addr(bp, addr, af->sockaddr_len,
+				 SCTP_ADDR_SRC, GFP_ATOMIC);
+
+	/* Copy back into socket for getsockname() use. */
+	if (!ret) {
+		inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num);
+		sp->pf->to_sk_saddr(addr, sk);
+	}
+
+	return ret;
+}
+
+ /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
+ *
+ * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
+ * at any one time.  If a sender, after sending an ASCONF chunk, decides
+ * it needs to transfer another ASCONF Chunk, it MUST wait until the
+ * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
+ * subsequent ASCONF. Note this restriction binds each side, so at any
+ * time two ASCONF may be in-transit on any given association (one sent
+ * from each endpoint).
+ */
+static int sctp_send_asconf(struct sctp_association *asoc,
+			    struct sctp_chunk *chunk)
+{
+	struct net 	*net = sock_net(asoc->base.sk);
+	int		retval = 0;
+
+	/* If there is an outstanding ASCONF chunk, queue it for later
+	 * transmission.
+	 */
+	if (asoc->addip_last_asconf) {
+		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
+		goto out;
+	}
+
+	/* Hold the chunk until an ASCONF_ACK is received. */
+	sctp_chunk_hold(chunk);
+	retval = sctp_primitive_ASCONF(net, asoc, chunk);
+	if (retval)
+		sctp_chunk_free(chunk);
+	else
+		asoc->addip_last_asconf = chunk;
+
+out:
+	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_setsockopt_bindx() is supposed to call this function.
+ */
+static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
+{
+	int cnt;
+	int retval = 0;
+	void *addr_buf;
+	struct sockaddr *sa_addr;
+	struct sctp_af *af;
+
+	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n", __func__, sk,
+		 addrs, addrcnt);
+
+	addr_buf = addrs;
+	for (cnt = 0; cnt < addrcnt; cnt++) {
+		/* The list may contain either IPv4 or IPv6 address;
+		 * determine the address length for walking thru the list.
+		 */
+		sa_addr = addr_buf;
+		af = sctp_get_af_specific(sa_addr->sa_family);
+		if (!af) {
+			retval = -EINVAL;
+			goto err_bindx_add;
+		}
+
+		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
+				      af->sockaddr_len);
+
+		addr_buf += af->sockaddr_len;
+
+err_bindx_add:
+		if (retval < 0) {
+			/* Failed. Cleanup the ones that have been added */
+			if (cnt > 0)
+				sctp_bindx_rem(sk, addrs, cnt);
+			return retval;
+		}
+	}
+
+	return retval;
+}
+
+/* Send an ASCONF chunk with Add IP address parameters to all the peers of the
+ * associations that are part of the endpoint indicating that a list of local
+ * addresses are added to the endpoint.
+ *
+ * If any of the addresses is already in the bind address list of the
+ * association, we do not send the chunk for that association.  But it will not
+ * affect other associations.
+ *
+ * Only sctp_setsockopt_bindx() is supposed to call this function.
+ */
+static int sctp_send_asconf_add_ip(struct sock		*sk,
+				   struct sockaddr	*addrs,
+				   int 			addrcnt)
+{
+	struct net *net = sock_net(sk);
+	struct sctp_sock		*sp;
+	struct sctp_endpoint		*ep;
+	struct sctp_association		*asoc;
+	struct sctp_bind_addr		*bp;
+	struct sctp_chunk		*chunk;
+	struct sctp_sockaddr_entry	*laddr;
+	union sctp_addr			*addr;
+	union sctp_addr			saveaddr;
+	void				*addr_buf;
+	struct sctp_af			*af;
+	struct list_head		*p;
+	int 				i;
+	int 				retval = 0;
+
+	if (!net->sctp.addip_enable)
+		return retval;
+
+	sp = sctp_sk(sk);
+	ep = sp->ep;
+
+	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
+		 __func__, sk, addrs, addrcnt);
+
+	list_for_each_entry(asoc, &ep->asocs, asocs) {
+		if (!asoc->peer.asconf_capable)
+			continue;
+
+		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
+			continue;
+
+		if (!sctp_state(asoc, ESTABLISHED))
+			continue;
+
+		/* Check if any address in the packed array of addresses is
+		 * in the bind address list of the association. If so,
+		 * do not send the asconf chunk to its peer, but continue with
+		 * other associations.
+		 */
+		addr_buf = addrs;
+		for (i = 0; i < addrcnt; i++) {
+			addr = addr_buf;
+			af = sctp_get_af_specific(addr->v4.sin_family);
+			if (!af) {
+				retval = -EINVAL;
+				goto out;
+			}
+
+			if (sctp_assoc_lookup_laddr(asoc, addr))
+				break;
+
+			addr_buf += af->sockaddr_len;
+		}
+		if (i < addrcnt)
+			continue;
+
+		/* Use the first valid address in bind addr list of
+		 * association as Address Parameter of ASCONF CHUNK.
+		 */
+		bp = &asoc->base.bind_addr;
+		p = bp->address_list.next;
+		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
+		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
+						   addrcnt, SCTP_PARAM_ADD_IP);
+		if (!chunk) {
+			retval = -ENOMEM;
+			goto out;
+		}
+
+		/* Add the new addresses to the bind address list with
+		 * use_as_src set to 0.
+		 */
+		addr_buf = addrs;
+		for (i = 0; i < addrcnt; i++) {
+			addr = addr_buf;
+			af = sctp_get_af_specific(addr->v4.sin_family);
+			memcpy(&saveaddr, addr, af->sockaddr_len);
+			retval = sctp_add_bind_addr(bp, &saveaddr,
+						    sizeof(saveaddr),
+						    SCTP_ADDR_NEW, GFP_ATOMIC);
+			addr_buf += af->sockaddr_len;
+		}
+		if (asoc->src_out_of_asoc_ok) {
+			struct sctp_transport *trans;
+
+			list_for_each_entry(trans,
+			    &asoc->peer.transport_addr_list, transports) {
+				trans->cwnd = min(4*asoc->pathmtu, max_t(__u32,
+				    2*asoc->pathmtu, 4380));
+				trans->ssthresh = asoc->peer.i.a_rwnd;
+				trans->rto = asoc->rto_initial;
+				sctp_max_rto(asoc, trans);
+				trans->rtt = trans->srtt = trans->rttvar = 0;
+				/* Clear the source and route cache */
+				sctp_transport_route(trans, NULL,
+						     sctp_sk(asoc->base.sk));
+			}
+		}
+		retval = sctp_send_asconf(asoc, chunk);
+	}
+
+out:
+	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_setsockopt_bindx() is supposed to call this function.
+ */
+static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
+	int cnt;
+	struct sctp_bind_addr *bp = &ep->base.bind_addr;
+	int retval = 0;
+	void *addr_buf;
+	union sctp_addr *sa_addr;
+	struct sctp_af *af;
+
+	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
+		 __func__, sk, addrs, addrcnt);
+
+	addr_buf = addrs;
+	for (cnt = 0; cnt < addrcnt; cnt++) {
+		/* If the bind address list is empty or 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) ||
+		    (sctp_list_single_entry(&bp->address_list))) {
+			retval = -EBUSY;
+			goto err_bindx_rem;
+		}
+
+		sa_addr = addr_buf;
+		af = sctp_get_af_specific(sa_addr->sa.sa_family);
+		if (!af) {
+			retval = -EINVAL;
+			goto err_bindx_rem;
+		}
+
+		if (!af->addr_valid(sa_addr, sp, NULL)) {
+			retval = -EADDRNOTAVAIL;
+			goto err_bindx_rem;
+		}
+
+		if (sa_addr->v4.sin_port &&
+		    sa_addr->v4.sin_port != htons(bp->port)) {
+			retval = -EINVAL;
+			goto err_bindx_rem;
+		}
+
+		if (!sa_addr->v4.sin_port)
+			sa_addr->v4.sin_port = htons(bp->port);
+
+		/* FIXME - There is probably a need to check if sk->sk_saddr and
+		 * sk->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
+		 */
+		retval = sctp_del_bind_addr(bp, sa_addr);
+
+		addr_buf += af->sockaddr_len;
+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;
+		}
+	}
+
+	return retval;
+}
+
+/* Send an ASCONF chunk with Delete IP address parameters to all the peers of
+ * the associations that are part of the endpoint indicating that a list of
+ * local addresses are removed from the endpoint.
+ *
+ * If any of the addresses is already in the bind address list of the
+ * association, we do not send the chunk for that association.  But it will not
+ * affect other associations.
+ *
+ * Only sctp_setsockopt_bindx() is supposed to call this function.
+ */
+static int sctp_send_asconf_del_ip(struct sock		*sk,
+				   struct sockaddr	*addrs,
+				   int			addrcnt)
+{
+	struct net *net = sock_net(sk);
+	struct sctp_sock	*sp;
+	struct sctp_endpoint	*ep;
+	struct sctp_association	*asoc;
+	struct sctp_transport	*transport;
+	struct sctp_bind_addr	*bp;
+	struct sctp_chunk	*chunk;
+	union sctp_addr		*laddr;
+	void			*addr_buf;
+	struct sctp_af		*af;
+	struct sctp_sockaddr_entry *saddr;
+	int 			i;
+	int 			retval = 0;
+	int			stored = 0;
+
+	chunk = NULL;
+	if (!net->sctp.addip_enable)
+		return retval;
+
+	sp = sctp_sk(sk);
+	ep = sp->ep;
+
+	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
+		 __func__, sk, addrs, addrcnt);
+
+	list_for_each_entry(asoc, &ep->asocs, asocs) {
+
+		if (!asoc->peer.asconf_capable)
+			continue;
+
+		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
+			continue;
+
+		if (!sctp_state(asoc, ESTABLISHED))
+			continue;
+
+		/* Check if any address in the packed array of addresses is
+		 * not present in the bind address list of the association.
+		 * If so, do not send the asconf chunk to its peer, but
+		 * continue with other associations.
+		 */
+		addr_buf = addrs;
+		for (i = 0; i < addrcnt; i++) {
+			laddr = addr_buf;
+			af = sctp_get_af_specific(laddr->v4.sin_family);
+			if (!af) {
+				retval = -EINVAL;
+				goto out;
+			}
+
+			if (!sctp_assoc_lookup_laddr(asoc, laddr))
+				break;
+
+			addr_buf += af->sockaddr_len;
+		}
+		if (i < addrcnt)
+			continue;
+
+		/* Find one address in the association's bind address list
+		 * that is not in the packed array of addresses. This is to
+		 * make sure that we do not delete all the addresses in the
+		 * association.
+		 */
+		bp = &asoc->base.bind_addr;
+		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
+					       addrcnt, sp);
+		if ((laddr == NULL) && (addrcnt == 1)) {
+			if (asoc->asconf_addr_del_pending)
+				continue;
+			asoc->asconf_addr_del_pending =
+			    kzalloc(sizeof(union sctp_addr), GFP_ATOMIC);
+			if (asoc->asconf_addr_del_pending == NULL) {
+				retval = -ENOMEM;
+				goto out;
+			}
+			asoc->asconf_addr_del_pending->sa.sa_family =
+				    addrs->sa_family;
+			asoc->asconf_addr_del_pending->v4.sin_port =
+				    htons(bp->port);
+			if (addrs->sa_family == AF_INET) {
+				struct sockaddr_in *sin;
+
+				sin = (struct sockaddr_in *)addrs;
+				asoc->asconf_addr_del_pending->v4.sin_addr.s_addr = sin->sin_addr.s_addr;
+			} else if (addrs->sa_family == AF_INET6) {
+				struct sockaddr_in6 *sin6;
+
+				sin6 = (struct sockaddr_in6 *)addrs;
+				asoc->asconf_addr_del_pending->v6.sin6_addr = sin6->sin6_addr;
+			}
+
+			pr_debug("%s: keep the last address asoc:%p %pISc at %p\n",
+				 __func__, asoc, &asoc->asconf_addr_del_pending->sa,
+				 asoc->asconf_addr_del_pending);
+
+			asoc->src_out_of_asoc_ok = 1;
+			stored = 1;
+			goto skip_mkasconf;
+		}
+
+		if (laddr == NULL)
+			return -EINVAL;
+
+		/* We do not need RCU protection throughout this loop
+		 * because this is done under a socket lock from the
+		 * setsockopt call.
+		 */
+		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
+						   SCTP_PARAM_DEL_IP);
+		if (!chunk) {
+			retval = -ENOMEM;
+			goto out;
+		}
+
+skip_mkasconf:
+		/* Reset use_as_src flag for the addresses in the bind address
+		 * list that are to be deleted.
+		 */
+		addr_buf = addrs;
+		for (i = 0; i < addrcnt; i++) {
+			laddr = addr_buf;
+			af = sctp_get_af_specific(laddr->v4.sin_family);
+			list_for_each_entry(saddr, &bp->address_list, list) {
+				if (sctp_cmp_addr_exact(&saddr->a, laddr))
+					saddr->state = SCTP_ADDR_DEL;
+			}
+			addr_buf += af->sockaddr_len;
+		}
+
+		/* Update the route and saddr entries for all the transports
+		 * as some of the addresses in the bind address list are
+		 * about to be deleted and cannot be used as source addresses.
+		 */
+		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
+					transports) {
+			sctp_transport_route(transport, NULL,
+					     sctp_sk(asoc->base.sk));
+		}
+
+		if (stored)
+			/* We don't need to transmit ASCONF */
+			continue;
+		retval = sctp_send_asconf(asoc, chunk);
+	}
+out:
+	return retval;
+}
+
+/* set addr events to assocs in the endpoint.  ep and addr_wq must be locked */
+int sctp_asconf_mgmt(struct sctp_sock *sp, struct sctp_sockaddr_entry *addrw)
+{
+	struct sock *sk = sctp_opt2sk(sp);
+	union sctp_addr *addr;
+	struct sctp_af *af;
+
+	/* It is safe to write port space in caller. */
+	addr = &addrw->a;
+	addr->v4.sin_port = htons(sp->ep->base.bind_addr.port);
+	af = sctp_get_af_specific(addr->sa.sa_family);
+	if (!af)
+		return -EINVAL;
+	if (sctp_verify_addr(sk, addr, af->sockaddr_len))
+		return -EINVAL;
+
+	if (addrw->state == SCTP_ADDR_NEW)
+		return sctp_send_asconf_add_ip(sk, (struct sockaddr *)addr, 1);
+	else
+		return sctp_send_asconf_del_ip(sk, (struct sockaddr *)addr, 1);
+}
+
+/* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
+ *
+ * API 8.1
+ * int sctp_bindx(int sd, struct sockaddr *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 IN6ADDR_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 its appropriate structure (i.e. struct
+ * sockaddr_in or struct sockaddr_in6) the family of the address type
+ * must be used to distinguish the address length (note that this
+ * representation is termed a "packed array" of addresses). 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.
+ *
+ * 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_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
+ * association, and SCTP_BINDX_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. If the endpoint supports dynamic
+ * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
+ * endpoint to send the appropriate message to the peer to change the
+ * peers address lists.
+ *
+ * Adding and removing addresses from a connected association is
+ * optional functionality. Implementations that do not support this
+ * functionality should return EOPNOTSUPP.
+ *
+ * Basically do nothing but copying the addresses from user to kernel
+ * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
+ * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
+ * from userspace.
+ *
+ * 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.
+ */
+static int sctp_setsockopt_bindx(struct sock *sk,
+				 struct sockaddr __user *addrs,
+				 int addrs_size, int op)
+{
+	struct sockaddr *kaddrs;
+	int err;
+	int addrcnt = 0;
+	int walk_size = 0;
+	struct sockaddr *sa_addr;
+	void *addr_buf;
+	struct sctp_af *af;
+
+	pr_debug("%s: sk:%p addrs:%p addrs_size:%d opt:%d\n",
+		 __func__, sk, addrs, addrs_size, op);
+
+	if (unlikely(addrs_size <= 0))
+		return -EINVAL;
+
+	kaddrs = memdup_user(addrs, addrs_size);
+	if (unlikely(IS_ERR(kaddrs)))
+		return PTR_ERR(kaddrs);
+
+	/* Walk through the addrs buffer and count the number of addresses. */
+	addr_buf = kaddrs;
+	while (walk_size < addrs_size) {
+		if (walk_size + sizeof(sa_family_t) > addrs_size) {
+			kfree(kaddrs);
+			return -EINVAL;
+		}
+
+		sa_addr = addr_buf;
+		af = sctp_get_af_specific(sa_addr->sa_family);
+
+		/* If the address family is not supported or if this address
+		 * causes the address buffer to overflow return EINVAL.
+		 */
+		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
+			kfree(kaddrs);
+			return -EINVAL;
+		}
+		addrcnt++;
+		addr_buf += af->sockaddr_len;
+		walk_size += af->sockaddr_len;
+	}
+
+	/* Do the work. */
+	switch (op) {
+	case SCTP_BINDX_ADD_ADDR:
+		/* Allow security module to validate bindx addresses. */
+		err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_BINDX_ADD,
+						 (struct sockaddr *)kaddrs,
+						 addrs_size);
+		if (err)
+			goto out;
+		err = sctp_bindx_add(sk, kaddrs, addrcnt);
+		if (err)
+			goto out;
+		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
+		break;
+
+	case SCTP_BINDX_REM_ADDR:
+		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
+		if (err)
+			goto out;
+		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
+		break;
+
+	default:
+		err = -EINVAL;
+		break;
+	}
+
+out:
+	kfree(kaddrs);
+
+	return err;
+}
+
+/* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
+ *
+ * Common routine for handling connect() and sctp_connectx().
+ * Connect will come in with just a single address.
+ */
+static int __sctp_connect(struct sock *sk,
+			  struct sockaddr *kaddrs,
+			  int addrs_size, int flags,
+			  sctp_assoc_t *assoc_id)
+{
+	struct net *net = sock_net(sk);
+	struct sctp_sock *sp;
+	struct sctp_endpoint *ep;
+	struct sctp_association *asoc = NULL;
+	struct sctp_association *asoc2;
+	struct sctp_transport *transport;
+	union sctp_addr to;
+	enum sctp_scope scope;
+	long timeo;
+	int err = 0;
+	int addrcnt = 0;
+	int walk_size = 0;
+	union sctp_addr *sa_addr = NULL;
+	void *addr_buf;
+	unsigned short port;
+
+	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_sstate(sk, ESTABLISHED) || sctp_sstate(sk, CLOSING) ||
+	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
+		err = -EISCONN;
+		goto out_free;
+	}
+
+	/* Walk through the addrs buffer and count the number of addresses. */
+	addr_buf = kaddrs;
+	while (walk_size < addrs_size) {
+		struct sctp_af *af;
+
+		if (walk_size + sizeof(sa_family_t) > addrs_size) {
+			err = -EINVAL;
+			goto out_free;
+		}
+
+		sa_addr = addr_buf;
+		af = sctp_get_af_specific(sa_addr->sa.sa_family);
+
+		/* If the address family is not supported or if this address
+		 * causes the address buffer to overflow return EINVAL.
+		 */
+		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
+			err = -EINVAL;
+			goto out_free;
+		}
+
+		port = ntohs(sa_addr->v4.sin_port);
+
+		/* Save current address so we can work with it */
+		memcpy(&to, sa_addr, af->sockaddr_len);
+
+		err = sctp_verify_addr(sk, &to, af->sockaddr_len);
+		if (err)
+			goto out_free;
+
+		/* Make sure the destination port is correctly set
+		 * in all addresses.
+		 */
+		if (asoc && asoc->peer.port && asoc->peer.port != port) {
+			err = -EINVAL;
+			goto out_free;
+		}
+
+		/* Check if there already is a matching association on the
+		 * endpoint (other than the one created here).
+		 */
+		asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
+		if (asoc2 && asoc2 != asoc) {
+			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
+				err = -EISCONN;
+			else
+				err = -EALREADY;
+			goto out_free;
+		}
+
+		/* 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_free;
+		}
+
+		if (!asoc) {
+			/* If a bind() or sctp_bindx() is not called prior to
+			 * an sctp_connectx() 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_free;
+				}
+			} else {
+				/*
+				 * If an unprivileged user inherits a 1-many
+				 * style socket with open associations on a
+				 * privileged port, it MAY be permitted to
+				 * accept new associations, but it SHOULD NOT
+				 * be permitted to open new associations.
+				 */
+				if (ep->base.bind_addr.port <
+				    inet_prot_sock(net) &&
+				    !ns_capable(net->user_ns,
+				    CAP_NET_BIND_SERVICE)) {
+					err = -EACCES;
+					goto out_free;
+				}
+			}
+
+			scope = sctp_scope(&to);
+			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
+			if (!asoc) {
+				err = -ENOMEM;
+				goto out_free;
+			}
+
+			err = sctp_assoc_set_bind_addr_from_ep(asoc, scope,
+							      GFP_KERNEL);
+			if (err < 0) {
+				goto out_free;
+			}
+
+		}
+
+		/* Prime the peer's transport structures.  */
+		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
+						SCTP_UNKNOWN);
+		if (!transport) {
+			err = -ENOMEM;
+			goto out_free;
+		}
+
+		addrcnt++;
+		addr_buf += af->sockaddr_len;
+		walk_size += af->sockaddr_len;
+	}
+
+	/* In case the user of sctp_connectx() wants an association
+	 * id back, assign one now.
+	 */
+	if (assoc_id) {
+		err = sctp_assoc_set_id(asoc, GFP_KERNEL);
+		if (err < 0)
+			goto out_free;
+	}
+
+	err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
+	if (err < 0) {
+		goto out_free;
+	}
+
+	/* Initialize sk's dport and daddr for getpeername() */
+	inet_sk(sk)->inet_dport = htons(asoc->peer.port);
+	sp->pf->to_sk_daddr(sa_addr, sk);
+	sk->sk_err = 0;
+
+	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
+
+	if (assoc_id)
+		*assoc_id = asoc->assoc_id;
+
+	err = sctp_wait_for_connect(asoc, &timeo);
+	/* Note: the asoc may be freed after the return of
+	 * sctp_wait_for_connect.
+	 */
+
+	/* Don't free association on exit. */
+	asoc = NULL;
+
+out_free:
+	pr_debug("%s: took out_free path with asoc:%p kaddrs:%p err:%d\n",
+		 __func__, asoc, kaddrs, err);
+
+	if (asoc) {
+		/* sctp_primitive_ASSOCIATE may have added this association
+		 * To the hash table, try to unhash it, just in case, its a noop
+		 * if it wasn't hashed so we're safe
+		 */
+		sctp_association_free(asoc);
+	}
+	return err;
+}
+
+/* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
+ *
+ * API 8.9
+ * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt,
+ * 			sctp_assoc_t *asoc);
+ *
+ * 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 IN6ADDR_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 its appropriate structure (i.e. struct
+ * sockaddr_in or struct sockaddr_in6) the family of the address type
+ * must be used to distengish the address length (note that this
+ * representation is termed a "packed array" of addresses). The caller
+ * specifies the number of addresses in the array with addrcnt.
+ *
+ * On success, sctp_connectx() returns 0. It also sets the assoc_id to
+ * the association id of the new association.  On failure, sctp_connectx()
+ * returns -1, and sets errno to the appropriate error code.  The assoc_id
+ * is not touched by the kernel.
+ *
+ * For SCTP, the port given in each socket address must be the same, or
+ * sctp_connectx() will fail, setting errno to EINVAL.
+ *
+ * An application can use sctp_connectx to initiate an association with
+ * an endpoint that is multi-homed.  Much like sctp_bindx() this call
+ * allows a caller to specify multiple addresses at which a peer can be
+ * reached.  The way the SCTP stack uses the list of addresses to set up
+ * the association is implementation dependent.  This function only
+ * specifies that the stack will try to make use of all the addresses in
+ * the list when needed.
+ *
+ * Note that the list of addresses passed in is only used for setting up
+ * the association.  It does not necessarily equal the set of addresses
+ * the peer uses for the resulting association.  If the caller wants to
+ * find out the set of peer addresses, it must use sctp_getpaddrs() to
+ * retrieve them after the association has been set up.
+ *
+ * Basically do nothing but copying the addresses from user to kernel
+ * land and invoking either sctp_connectx(). This is used for tunneling
+ * the sctp_connectx() request through sctp_setsockopt() from userspace.
+ *
+ * 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
+ *
+ * Returns >=0 if ok, <0 errno code on error.
+ */
+static int __sctp_setsockopt_connectx(struct sock *sk,
+				      struct sockaddr __user *addrs,
+				      int addrs_size,
+				      sctp_assoc_t *assoc_id)
+{
+	struct sockaddr *kaddrs;
+	int err = 0, flags = 0;
+
+	pr_debug("%s: sk:%p addrs:%p addrs_size:%d\n",
+		 __func__, sk, addrs, addrs_size);
+
+	if (unlikely(addrs_size <= 0))
+		return -EINVAL;
+
+	kaddrs = memdup_user(addrs, addrs_size);
+	if (unlikely(IS_ERR(kaddrs)))
+		return PTR_ERR(kaddrs);
+
+	/* Allow security module to validate connectx addresses. */
+	err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_CONNECTX,
+					 (struct sockaddr *)kaddrs,
+					  addrs_size);
+	if (err)
+		goto out_free;
+
+	/* in-kernel sockets don't generally have a file allocated to them
+	 * if all they do is call sock_create_kern().
+	 */
+	if (sk->sk_socket->file)
+		flags = sk->sk_socket->file->f_flags;
+
+	err = __sctp_connect(sk, kaddrs, addrs_size, flags, assoc_id);
+
+out_free:
+	kfree(kaddrs);
+
+	return err;
+}
+
+/*
+ * This is an older interface.  It's kept for backward compatibility
+ * to the option that doesn't provide association id.
+ */
+static int sctp_setsockopt_connectx_old(struct sock *sk,
+					struct sockaddr __user *addrs,
+					int addrs_size)
+{
+	return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL);
+}
+
+/*
+ * New interface for the API.  The since the API is done with a socket
+ * option, to make it simple we feed back the association id is as a return
+ * indication to the call.  Error is always negative and association id is
+ * always positive.
+ */
+static int sctp_setsockopt_connectx(struct sock *sk,
+				    struct sockaddr __user *addrs,
+				    int addrs_size)
+{
+	sctp_assoc_t assoc_id = 0;
+	int err = 0;
+
+	err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id);
+
+	if (err)
+		return err;
+	else
+		return assoc_id;
+}
+
+/*
+ * New (hopefully final) interface for the API.
+ * We use the sctp_getaddrs_old structure so that use-space library
+ * can avoid any unnecessary allocations. The only different part
+ * is that we store the actual length of the address buffer into the
+ * addrs_num structure member. That way we can re-use the existing
+ * code.
+ */
+#ifdef CONFIG_COMPAT
+struct compat_sctp_getaddrs_old {
+	sctp_assoc_t	assoc_id;
+	s32		addr_num;
+	compat_uptr_t	addrs;		/* struct sockaddr * */
+};
+#endif
+
+static int sctp_getsockopt_connectx3(struct sock *sk, int len,
+				     char __user *optval,
+				     int __user *optlen)
+{
+	struct sctp_getaddrs_old param;
+	sctp_assoc_t assoc_id = 0;
+	int err = 0;
+
+#ifdef CONFIG_COMPAT
+	if (in_compat_syscall()) {
+		struct compat_sctp_getaddrs_old param32;
+
+		if (len < sizeof(param32))
+			return -EINVAL;
+		if (copy_from_user(&param32, optval, sizeof(param32)))
+			return -EFAULT;
+
+		param.assoc_id = param32.assoc_id;
+		param.addr_num = param32.addr_num;
+		param.addrs = compat_ptr(param32.addrs);
+	} else
+#endif
+	{
+		if (len < sizeof(param))
+			return -EINVAL;
+		if (copy_from_user(&param, optval, sizeof(param)))
+			return -EFAULT;
+	}
+
+	err = __sctp_setsockopt_connectx(sk, (struct sockaddr __user *)
+					 param.addrs, param.addr_num,
+					 &assoc_id);
+	if (err == 0 || err == -EINPROGRESS) {
+		if (copy_to_user(optval, &assoc_id, sizeof(assoc_id)))
+			return -EFAULT;
+		if (put_user(sizeof(assoc_id), optlen))
+			return -EFAULT;
+	}
+
+	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.
+ *
+ * 4.1.6 close() - TCP Style Syntax
+ *
+ * Applications use close() to gracefully close down an association.
+ *
+ * The syntax is:
+ *
+ *    int close(int sd);
+ *
+ *      sd      - the socket descriptor of the association to be closed.
+ *
+ * After an application calls close() on a socket descriptor, no further
+ * socket operations will succeed on that descriptor.
+ *
+ * API 7.1.4 SO_LINGER
+ *
+ * An application using the TCP-style socket can use this option to
+ * perform the SCTP ABORT primitive.  The linger option structure is:
+ *
+ *  struct  linger {
+ *     int     l_onoff;                // option on/off
+ *     int     l_linger;               // linger time
+ * };
+ *
+ * To enable the option, set l_onoff to 1.  If the l_linger value is set
+ * to 0, calling close() is the same as the ABORT primitive.  If the
+ * value is set to a negative value, the setsockopt() call will return
+ * an error.  If the value is set to a positive value linger_time, the
+ * close() can be blocked for at most linger_time ms.  If the graceful
+ * shutdown phase does not finish during this period, close() will
+ * return but the graceful shutdown phase continues in the system.
+ */
+static void sctp_close(struct sock *sk, long timeout)
+{
+	struct net *net = sock_net(sk);
+	struct sctp_endpoint *ep;
+	struct sctp_association *asoc;
+	struct list_head *pos, *temp;
+	unsigned int data_was_unread;
+
+	pr_debug("%s: sk:%p, timeout:%ld\n", __func__, sk, timeout);
+
+	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
+	sk->sk_shutdown = SHUTDOWN_MASK;
+	inet_sk_set_state(sk, SCTP_SS_CLOSING);
+
+	ep = sctp_sk(sk)->ep;
+
+	/* Clean up any skbs sitting on the receive queue.  */
+	data_was_unread = sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
+	data_was_unread += sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
+
+	/* Walk all associations on an endpoint.  */
+	list_for_each_safe(pos, temp, &ep->asocs) {
+		asoc = list_entry(pos, struct sctp_association, asocs);
+
+		if (sctp_style(sk, TCP)) {
+			/* A closed association can still be in the list if
+			 * it belongs to a TCP-style listening socket that is
+			 * not yet accepted. If so, free it. If not, send an
+			 * ABORT or SHUTDOWN based on the linger options.
+			 */
+			if (sctp_state(asoc, CLOSED)) {
+				sctp_association_free(asoc);
+				continue;
+			}
+		}
+
+		if (data_was_unread || !skb_queue_empty(&asoc->ulpq.lobby) ||
+		    !skb_queue_empty(&asoc->ulpq.reasm) ||
+		    !skb_queue_empty(&asoc->ulpq.reasm_uo) ||
+		    (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime)) {
+			struct sctp_chunk *chunk;
+
+			chunk = sctp_make_abort_user(asoc, NULL, 0);
+			sctp_primitive_ABORT(net, asoc, chunk);
+		} else
+			sctp_primitive_SHUTDOWN(net, asoc, NULL);
+	}
+
+	/* On a TCP-style socket, block for at most linger_time if set. */
+	if (sctp_style(sk, TCP) && timeout)
+		sctp_wait_for_close(sk, timeout);
+
+	/* This will run the backlog queue.  */
+	release_sock(sk);
+
+	/* Supposedly, no process has access to the socket, but
+	 * the net layers still may.
+	 * Also, sctp_destroy_sock() needs to be called with addr_wq_lock
+	 * held and that should be grabbed before socket lock.
+	 */
+	spin_lock_bh(&net->sctp.addr_wq_lock);
+	bh_lock_sock_nested(sk);
+
+	/* Hold the sock, since sk_common_release() will put sock_put()
+	 * and we have just a little more cleanup.
+	 */
+	sock_hold(sk);
+	sk_common_release(sk);
+
+	bh_unlock_sock(sk);
+	spin_unlock_bh(&net->sctp.addr_wq_lock);
+
+	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 sk_stream_wait_memory(). */
+
+static int sctp_msghdr_parse(const struct msghdr *msg,
+			     struct sctp_cmsgs *cmsgs);
+
+static int sctp_sendmsg_parse(struct sock *sk, struct sctp_cmsgs *cmsgs,
+			      struct sctp_sndrcvinfo *srinfo,
+			      const struct msghdr *msg, size_t msg_len)
+{
+	__u16 sflags;
+	int err;
+
+	if (sctp_sstate(sk, LISTENING) && sctp_style(sk, TCP))
+		return -EPIPE;
+
+	if (msg_len > sk->sk_sndbuf)
+		return -EMSGSIZE;
+
+	memset(cmsgs, 0, sizeof(*cmsgs));
+	err = sctp_msghdr_parse(msg, cmsgs);
+	if (err) {
+		pr_debug("%s: msghdr parse err:%x\n", __func__, err);
+		return err;
+	}
+
+	memset(srinfo, 0, sizeof(*srinfo));
+	if (cmsgs->srinfo) {
+		srinfo->sinfo_stream = cmsgs->srinfo->sinfo_stream;
+		srinfo->sinfo_flags = cmsgs->srinfo->sinfo_flags;
+		srinfo->sinfo_ppid = cmsgs->srinfo->sinfo_ppid;
+		srinfo->sinfo_context = cmsgs->srinfo->sinfo_context;
+		srinfo->sinfo_assoc_id = cmsgs->srinfo->sinfo_assoc_id;
+		srinfo->sinfo_timetolive = cmsgs->srinfo->sinfo_timetolive;
+	}
+
+	if (cmsgs->sinfo) {
+		srinfo->sinfo_stream = cmsgs->sinfo->snd_sid;
+		srinfo->sinfo_flags = cmsgs->sinfo->snd_flags;
+		srinfo->sinfo_ppid = cmsgs->sinfo->snd_ppid;
+		srinfo->sinfo_context = cmsgs->sinfo->snd_context;
+		srinfo->sinfo_assoc_id = cmsgs->sinfo->snd_assoc_id;
+	}
+
+	if (cmsgs->prinfo) {
+		srinfo->sinfo_timetolive = cmsgs->prinfo->pr_value;
+		SCTP_PR_SET_POLICY(srinfo->sinfo_flags,
+				   cmsgs->prinfo->pr_policy);
+	}
+
+	sflags = srinfo->sinfo_flags;
+	if (!sflags && msg_len)
+		return 0;
+
+	if (sctp_style(sk, TCP) && (sflags & (SCTP_EOF | SCTP_ABORT)))
+		return -EINVAL;
+
+	if (((sflags & SCTP_EOF) && msg_len > 0) ||
+	    (!(sflags & (SCTP_EOF | SCTP_ABORT)) && msg_len == 0))
+		return -EINVAL;
+
+	if ((sflags & SCTP_ADDR_OVER) && !msg->msg_name)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int sctp_sendmsg_new_asoc(struct sock *sk, __u16 sflags,
+				 struct sctp_cmsgs *cmsgs,
+				 union sctp_addr *daddr,
+				 struct sctp_transport **tp)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct net *net = sock_net(sk);
+	struct sctp_association *asoc;
+	enum sctp_scope scope;
+	struct cmsghdr *cmsg;
+	__be32 flowinfo = 0;
+	struct sctp_af *af;
+	int err;
+
+	*tp = NULL;
+
+	if (sflags & (SCTP_EOF | SCTP_ABORT))
+		return -EINVAL;
+
+	if (sctp_style(sk, TCP) && (sctp_sstate(sk, ESTABLISHED) ||
+				    sctp_sstate(sk, CLOSING)))
+		return -EADDRNOTAVAIL;
+
+	if (sctp_endpoint_is_peeled_off(ep, daddr))
+		return -EADDRNOTAVAIL;
+
+	if (!ep->base.bind_addr.port) {
+		if (sctp_autobind(sk))
+			return -EAGAIN;
+	} else {
+		if (ep->base.bind_addr.port < inet_prot_sock(net) &&
+		    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
+			return -EACCES;
+	}
+
+	scope = sctp_scope(daddr);
+
+	/* Label connection socket for first association 1-to-many
+	 * style for client sequence socket()->sendmsg(). This
+	 * needs to be done before sctp_assoc_add_peer() as that will
+	 * set up the initial packet that needs to account for any
+	 * security ip options (CIPSO/CALIPSO) added to the packet.
+	 */
+	af = sctp_get_af_specific(daddr->sa.sa_family);
+	if (!af)
+		return -EINVAL;
+	err = security_sctp_bind_connect(sk, SCTP_SENDMSG_CONNECT,
+					 (struct sockaddr *)daddr,
+					 af->sockaddr_len);
+	if (err < 0)
+		return err;
+
+	asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
+	if (!asoc)
+		return -ENOMEM;
+
+	if (sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL) < 0) {
+		err = -ENOMEM;
+		goto free;
+	}
+
+	if (cmsgs->init) {
+		struct sctp_initmsg *init = cmsgs->init;
+
+		if (init->sinit_num_ostreams) {
+			__u16 outcnt = init->sinit_num_ostreams;
+
+			asoc->c.sinit_num_ostreams = outcnt;
+			/* outcnt has been changed, need to re-init stream */
+			err = sctp_stream_init(&asoc->stream, outcnt, 0,
+					       GFP_KERNEL);
+			if (err)
+				goto free;
+		}
+
+		if (init->sinit_max_instreams)
+			asoc->c.sinit_max_instreams = init->sinit_max_instreams;
+
+		if (init->sinit_max_attempts)
+			asoc->max_init_attempts = init->sinit_max_attempts;
+
+		if (init->sinit_max_init_timeo)
+			asoc->max_init_timeo =
+				msecs_to_jiffies(init->sinit_max_init_timeo);
+	}
+
+	*tp = sctp_assoc_add_peer(asoc, daddr, GFP_KERNEL, SCTP_UNKNOWN);
+	if (!*tp) {
+		err = -ENOMEM;
+		goto free;
+	}
+
+	if (!cmsgs->addrs_msg)
+		return 0;
+
+	if (daddr->sa.sa_family == AF_INET6)
+		flowinfo = daddr->v6.sin6_flowinfo;
+
+	/* sendv addr list parse */
+	for_each_cmsghdr(cmsg, cmsgs->addrs_msg) {
+		struct sctp_transport *transport;
+		struct sctp_association *old;
+		union sctp_addr _daddr;
+		int dlen;
+
+		if (cmsg->cmsg_level != IPPROTO_SCTP ||
+		    (cmsg->cmsg_type != SCTP_DSTADDRV4 &&
+		     cmsg->cmsg_type != SCTP_DSTADDRV6))
+			continue;
+
+		daddr = &_daddr;
+		memset(daddr, 0, sizeof(*daddr));
+		dlen = cmsg->cmsg_len - sizeof(struct cmsghdr);
+		if (cmsg->cmsg_type == SCTP_DSTADDRV4) {
+			if (dlen < sizeof(struct in_addr)) {
+				err = -EINVAL;
+				goto free;
+			}
+
+			dlen = sizeof(struct in_addr);
+			daddr->v4.sin_family = AF_INET;
+			daddr->v4.sin_port = htons(asoc->peer.port);
+			memcpy(&daddr->v4.sin_addr, CMSG_DATA(cmsg), dlen);
+		} else {
+			if (dlen < sizeof(struct in6_addr)) {
+				err = -EINVAL;
+				goto free;
+			}
+
+			dlen = sizeof(struct in6_addr);
+			daddr->v6.sin6_flowinfo = flowinfo;
+			daddr->v6.sin6_family = AF_INET6;
+			daddr->v6.sin6_port = htons(asoc->peer.port);
+			memcpy(&daddr->v6.sin6_addr, CMSG_DATA(cmsg), dlen);
+		}
+		err = sctp_verify_addr(sk, daddr, sizeof(*daddr));
+		if (err)
+			goto free;
+
+		old = sctp_endpoint_lookup_assoc(ep, daddr, &transport);
+		if (old && old != asoc) {
+			if (old->state >= SCTP_STATE_ESTABLISHED)
+				err = -EISCONN;
+			else
+				err = -EALREADY;
+			goto free;
+		}
+
+		if (sctp_endpoint_is_peeled_off(ep, daddr)) {
+			err = -EADDRNOTAVAIL;
+			goto free;
+		}
+
+		transport = sctp_assoc_add_peer(asoc, daddr, GFP_KERNEL,
+						SCTP_UNKNOWN);
+		if (!transport) {
+			err = -ENOMEM;
+			goto free;
+		}
+	}
+
+	return 0;
+
+free:
+	sctp_association_free(asoc);
+	return err;
+}
+
+static int sctp_sendmsg_check_sflags(struct sctp_association *asoc,
+				     __u16 sflags, struct msghdr *msg,
+				     size_t msg_len)
+{
+	struct sock *sk = asoc->base.sk;
+	struct net *net = sock_net(sk);
+
+	if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP))
+		return -EPIPE;
+
+	if ((sflags & SCTP_SENDALL) && sctp_style(sk, UDP) &&
+	    !sctp_state(asoc, ESTABLISHED))
+		return 0;
+
+	if (sflags & SCTP_EOF) {
+		pr_debug("%s: shutting down association:%p\n", __func__, asoc);
+		sctp_primitive_SHUTDOWN(net, asoc, NULL);
+
+		return 0;
+	}
+
+	if (sflags & SCTP_ABORT) {
+		struct sctp_chunk *chunk;
+
+		chunk = sctp_make_abort_user(asoc, msg, msg_len);
+		if (!chunk)
+			return -ENOMEM;
+
+		pr_debug("%s: aborting association:%p\n", __func__, asoc);
+		sctp_primitive_ABORT(net, asoc, chunk);
+		iov_iter_revert(&msg->msg_iter, msg_len);
+
+		return 0;
+	}
+
+	return 1;
+}
+
+static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
+				struct msghdr *msg, size_t msg_len,
+				struct sctp_transport *transport,
+				struct sctp_sndrcvinfo *sinfo)
+{
+	struct sock *sk = asoc->base.sk;
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct net *net = sock_net(sk);
+	struct sctp_datamsg *datamsg;
+	bool wait_connect = false;
+	struct sctp_chunk *chunk;
+	long timeo;
+	int err;
+
+	if (sinfo->sinfo_stream >= asoc->stream.outcnt) {
+		err = -EINVAL;
+		goto err;
+	}
+
+	if (unlikely(!SCTP_SO(&asoc->stream, sinfo->sinfo_stream)->ext)) {
+		err = sctp_stream_init_ext(&asoc->stream, sinfo->sinfo_stream);
+		if (err)
+			goto err;
+	}
+
+	if (sp->disable_fragments && msg_len > asoc->frag_point) {
+		err = -EMSGSIZE;
+		goto err;
+	}
+
+	if (asoc->pmtu_pending) {
+		if (sp->param_flags & SPP_PMTUD_ENABLE)
+			sctp_assoc_sync_pmtu(asoc);
+		asoc->pmtu_pending = 0;
+	}
+
+	if (sctp_wspace(asoc) < (int)msg_len)
+		sctp_prsctp_prune(asoc, sinfo, msg_len - sctp_wspace(asoc));
+
+	if (sk_under_memory_pressure(sk))
+		sk_mem_reclaim(sk);
+
+	if (sctp_wspace(asoc) <= 0 || !sk_wmem_schedule(sk, msg_len)) {
+		timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
+		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
+		if (err)
+			goto err;
+	}
+
+	if (sctp_state(asoc, CLOSED)) {
+		err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
+		if (err)
+			goto err;
+
+		if (sp->strm_interleave) {
+			timeo = sock_sndtimeo(sk, 0);
+			err = sctp_wait_for_connect(asoc, &timeo);
+			if (err) {
+				err = -ESRCH;
+				goto err;
+			}
+		} else {
+			wait_connect = true;
+		}
+
+		pr_debug("%s: we associated primitively\n", __func__);
+	}
+
+	datamsg = sctp_datamsg_from_user(asoc, sinfo, &msg->msg_iter);
+	if (IS_ERR(datamsg)) {
+		err = PTR_ERR(datamsg);
+		goto err;
+	}
+
+	asoc->force_delay = !!(msg->msg_flags & MSG_MORE);
+
+	list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
+		sctp_chunk_hold(chunk);
+		sctp_set_owner_w(chunk);
+		chunk->transport = transport;
+	}
+
+	err = sctp_primitive_SEND(net, asoc, datamsg);
+	if (err) {
+		sctp_datamsg_free(datamsg);
+		goto err;
+	}
+
+	pr_debug("%s: we sent primitively\n", __func__);
+
+	sctp_datamsg_put(datamsg);
+
+	if (unlikely(wait_connect)) {
+		timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
+		sctp_wait_for_connect(asoc, &timeo);
+	}
+
+	err = msg_len;
+
+err:
+	return err;
+}
+
+static union sctp_addr *sctp_sendmsg_get_daddr(struct sock *sk,
+					       const struct msghdr *msg,
+					       struct sctp_cmsgs *cmsgs)
+{
+	union sctp_addr *daddr = NULL;
+	int err;
+
+	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
+		int len = msg->msg_namelen;
+
+		if (len > sizeof(*daddr))
+			len = sizeof(*daddr);
+
+		daddr = (union sctp_addr *)msg->msg_name;
+
+		err = sctp_verify_addr(sk, daddr, len);
+		if (err)
+			return ERR_PTR(err);
+	}
+
+	return daddr;
+}
+
+static void sctp_sendmsg_update_sinfo(struct sctp_association *asoc,
+				      struct sctp_sndrcvinfo *sinfo,
+				      struct sctp_cmsgs *cmsgs)
+{
+	if (!cmsgs->srinfo && !cmsgs->sinfo) {
+		sinfo->sinfo_stream = asoc->default_stream;
+		sinfo->sinfo_ppid = asoc->default_ppid;
+		sinfo->sinfo_context = asoc->default_context;
+		sinfo->sinfo_assoc_id = sctp_assoc2id(asoc);
+
+		if (!cmsgs->prinfo)
+			sinfo->sinfo_flags = asoc->default_flags;
+	}
+
+	if (!cmsgs->srinfo && !cmsgs->prinfo)
+		sinfo->sinfo_timetolive = asoc->default_timetolive;
+
+	if (cmsgs->authinfo) {
+		/* Reuse sinfo_tsn to indicate that authinfo was set and
+		 * sinfo_ssn to save the keyid on tx path.
+		 */
+		sinfo->sinfo_tsn = 1;
+		sinfo->sinfo_ssn = cmsgs->authinfo->auth_keynumber;
+	}
+}
+
+static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_transport *transport = NULL;
+	struct sctp_sndrcvinfo _sinfo, *sinfo;
+	struct sctp_association *asoc, *tmp;
+	struct sctp_cmsgs cmsgs;
+	union sctp_addr *daddr;
+	bool new = false;
+	__u16 sflags;
+	int err;
+
+	/* Parse and get snd_info */
+	err = sctp_sendmsg_parse(sk, &cmsgs, &_sinfo, msg, msg_len);
+	if (err)
+		goto out;
+
+	sinfo  = &_sinfo;
+	sflags = sinfo->sinfo_flags;
+
+	/* Get daddr from msg */
+	daddr = sctp_sendmsg_get_daddr(sk, msg, &cmsgs);
+	if (IS_ERR(daddr)) {
+		err = PTR_ERR(daddr);
+		goto out;
+	}
+
+	lock_sock(sk);
+
+	/* SCTP_SENDALL process */
+	if ((sflags & SCTP_SENDALL) && sctp_style(sk, UDP)) {
+		list_for_each_entry_safe(asoc, tmp, &ep->asocs, asocs) {
+			err = sctp_sendmsg_check_sflags(asoc, sflags, msg,
+							msg_len);
+			if (err == 0)
+				continue;
+			if (err < 0)
+				goto out_unlock;
+
+			sctp_sendmsg_update_sinfo(asoc, sinfo, &cmsgs);
+
+			err = sctp_sendmsg_to_asoc(asoc, msg, msg_len,
+						   NULL, sinfo);
+			if (err < 0)
+				goto out_unlock;
+
+			iov_iter_revert(&msg->msg_iter, err);
+		}
+
+		goto out_unlock;
+	}
+
+	/* Get and check or create asoc */
+	if (daddr) {
+		asoc = sctp_endpoint_lookup_assoc(ep, daddr, &transport);
+		if (asoc) {
+			err = sctp_sendmsg_check_sflags(asoc, sflags, msg,
+							msg_len);
+			if (err <= 0)
+				goto out_unlock;
+		} else {
+			err = sctp_sendmsg_new_asoc(sk, sflags, &cmsgs, daddr,
+						    &transport);
+			if (err)
+				goto out_unlock;
+
+			asoc = transport->asoc;
+			new = true;
+		}
+
+		if (!sctp_style(sk, TCP) && !(sflags & SCTP_ADDR_OVER))
+			transport = NULL;
+	} else {
+		asoc = sctp_id2assoc(sk, sinfo->sinfo_assoc_id);
+		if (!asoc) {
+			err = -EPIPE;
+			goto out_unlock;
+		}
+
+		err = sctp_sendmsg_check_sflags(asoc, sflags, msg, msg_len);
+		if (err <= 0)
+			goto out_unlock;
+	}
+
+	/* Update snd_info with the asoc */
+	sctp_sendmsg_update_sinfo(asoc, sinfo, &cmsgs);
+
+	/* Send msg to the asoc */
+	err = sctp_sendmsg_to_asoc(asoc, msg, msg_len, transport, sinfo);
+	if (err < 0 && err != -ESRCH && new)
+		sctp_association_free(asoc);
+
+out_unlock:
+	release_sock(sk);
+out:
+	return sctp_error(sk, msg->msg_flags, err);
+}
+
+/* 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);
+
+	skb_walk_frags(skb, list) {
+		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 int sctp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
+			int noblock, int flags, int *addr_len)
+{
+	struct sctp_ulpevent *event = NULL;
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sk_buff *skb, *head_skb;
+	int copied;
+	int err = 0;
+	int skb_len;
+
+	pr_debug("%s: sk:%p, msghdr:%p, len:%zd, noblock:%d, flags:0x%x, "
+		 "addr_len:%p)\n", __func__, sk, msg, len, noblock, flags,
+		 addr_len);
+
+	lock_sock(sk);
+
+	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED) &&
+	    !sctp_sstate(sk, CLOSING) && !sctp_sstate(sk, CLOSED)) {
+		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_msg(skb, 0, msg, copied);
+
+	event = sctp_skb2event(skb);
+
+	if (err)
+		goto out_free;
+
+	if (event->chunk && event->chunk->head_skb)
+		head_skb = event->chunk->head_skb;
+	else
+		head_skb = skb;
+	sock_recv_ts_and_drops(msg, sk, head_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(head_skb, msg->msg_name, addr_len);
+	}
+
+	/* Check if we allow SCTP_NXTINFO. */
+	if (sp->recvnxtinfo)
+		sctp_ulpevent_read_nxtinfo(event, msg, sk);
+	/* Check if we allow SCTP_RCVINFO. */
+	if (sp->recvrcvinfo)
+		sctp_ulpevent_read_rcvinfo(event, msg);
+	/* Check if we allow SCTP_SNDRCVINFO. */
+	if (sp->subscribe.sctp_data_io_event)
+		sctp_ulpevent_read_sndrcvinfo(event, msg);
+
+	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->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 event is freed.
+		 */
+		if (!sctp_ulpevent_is_notification(event))
+			sctp_assoc_rwnd_increase(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:
+	if (flags & MSG_PEEK) {
+		/* Release the skb reference acquired after peeking the skb in
+		 * sctp_skb_recv_datagram().
+		 */
+		kfree_skb(skb);
+	} else {
+		/* Free the event which includes releasing the reference to
+		 * the owner of the skb, freeing the skb and updating the
+		 * rwnd.
+		 */
+		sctp_ulpevent_free(event);
+	}
+out:
+	release_sock(sk);
+	return err;
+}
+
+/* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
+ *
+ * This option is a on/off flag.  If enabled no SCTP message
+ * fragmentation will be performed.  Instead if a message being sent
+ * exceeds the current PMTU size, the message will NOT be sent and
+ * instead a error will be indicated to the user.
+ */
+static int sctp_setsockopt_disable_fragments(struct sock *sk,
+					     char __user *optval,
+					     unsigned int optlen)
+{
+	int val;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
+
+	return 0;
+}
+
+static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
+				  unsigned int optlen)
+{
+	struct sctp_association *asoc;
+	struct sctp_ulpevent *event;
+
+	if (optlen > sizeof(struct sctp_event_subscribe))
+		return -EINVAL;
+	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
+		return -EFAULT;
+
+	/* At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
+	 * if there is no data to be sent or retransmit, the stack will
+	 * immediately send up this notification.
+	 */
+	if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT,
+				       &sctp_sk(sk)->subscribe)) {
+		asoc = sctp_id2assoc(sk, 0);
+
+		if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
+			event = sctp_ulpevent_make_sender_dry_event(asoc,
+					GFP_USER | __GFP_NOWARN);
+			if (!event)
+				return -ENOMEM;
+
+			asoc->stream.si->enqueue_event(&asoc->ulpq, event);
+		}
+	}
+
+	return 0;
+}
+
+/* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
+ *
+ * This socket option is applicable to the UDP-style socket only.  When
+ * set it will cause associations that are idle for more than the
+ * specified number of seconds to automatically close.  An association
+ * being idle is defined an association that has NOT sent or received
+ * user data.  The special value of '0' indicates that no automatic
+ * close of any associations should be performed.  The option expects an
+ * integer defining the number of seconds of idle time before an
+ * association is closed.
+ */
+static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
+				     unsigned int optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct net *net = sock_net(sk);
+
+	/* Applicable to UDP-style socket only */
+	if (sctp_style(sk, TCP))
+		return -EOPNOTSUPP;
+	if (optlen != sizeof(int))
+		return -EINVAL;
+	if (copy_from_user(&sp->autoclose, optval, optlen))
+		return -EFAULT;
+
+	if (sp->autoclose > net->sctp.max_autoclose)
+		sp->autoclose = net->sctp.max_autoclose;
+
+	return 0;
+}
+
+/* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
+ *
+ * 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 following structure is used to access and modify an
+ * address's parameters:
+ *
+ *  struct sctp_paddrparams {
+ *     sctp_assoc_t            spp_assoc_id;
+ *     struct sockaddr_storage spp_address;
+ *     uint32_t                spp_hbinterval;
+ *     uint16_t                spp_pathmaxrxt;
+ *     uint32_t                spp_pathmtu;
+ *     uint32_t                spp_sackdelay;
+ *     uint32_t                spp_flags;
+ *     uint32_t                spp_ipv6_flowlabel;
+ *     uint8_t                 spp_dscp;
+ * };
+ *
+ *   spp_assoc_id    - (one-to-many style socket) This is filled in the
+ *                     application, and identifies the association for
+ *                     this query.
+ *   spp_address     - This specifies which address is of interest.
+ *   spp_hbinterval  - This contains the value of the heartbeat interval,
+ *                     in milliseconds.  If a  value of zero
+ *                     is present in this field then no changes are to
+ *                     be made to this parameter.
+ *   spp_pathmaxrxt  - This contains the maximum number of
+ *                     retransmissions before this address shall be
+ *                     considered unreachable. If a  value of zero
+ *                     is present in this field then no changes are to
+ *                     be made to this parameter.
+ *   spp_pathmtu     - When Path MTU discovery is disabled the value
+ *                     specified here will be the "fixed" path mtu.
+ *                     Note that if the spp_address field is empty
+ *                     then all associations on this address will
+ *                     have this fixed path mtu set upon them.
+ *
+ *   spp_sackdelay   - When delayed sack is enabled, this value specifies
+ *                     the number of milliseconds that sacks will be delayed
+ *                     for. This value will apply to all addresses of an
+ *                     association if the spp_address field is empty. Note
+ *                     also, that if delayed sack is enabled and this
+ *                     value is set to 0, no change is made to the last
+ *                     recorded delayed sack timer value.
+ *
+ *   spp_flags       - These flags are used to control various features
+ *                     on an association. The flag field may contain
+ *                     zero or more of the following options.
+ *
+ *                     SPP_HB_ENABLE  - Enable heartbeats on the
+ *                     specified address. Note that if the address
+ *                     field is empty all addresses for the association
+ *                     have heartbeats enabled upon them.
+ *
+ *                     SPP_HB_DISABLE - Disable heartbeats on the
+ *                     speicifed address. Note that if the address
+ *                     field is empty all addresses for the association
+ *                     will have their heartbeats disabled. Note also
+ *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
+ *                     mutually exclusive, only one of these two should
+ *                     be specified. Enabling both fields will have
+ *                     undetermined results.
+ *
+ *                     SPP_HB_DEMAND - Request a user initiated heartbeat
+ *                     to be made immediately.
+ *
+ *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
+ *                     heartbeat delayis to be set to the value of 0
+ *                     milliseconds.
+ *
+ *                     SPP_PMTUD_ENABLE - This field will enable PMTU
+ *                     discovery upon the specified address. Note that
+ *                     if the address feild is empty then all addresses
+ *                     on the association are effected.
+ *
+ *                     SPP_PMTUD_DISABLE - This field will disable PMTU
+ *                     discovery upon the specified address. Note that
+ *                     if the address feild is empty then all addresses
+ *                     on the association are effected. Not also that
+ *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
+ *                     exclusive. Enabling both will have undetermined
+ *                     results.
+ *
+ *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
+ *                     on delayed sack. The time specified in spp_sackdelay
+ *                     is used to specify the sack delay for this address. Note
+ *                     that if spp_address is empty then all addresses will
+ *                     enable delayed sack and take on the sack delay
+ *                     value specified in spp_sackdelay.
+ *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
+ *                     off delayed sack. If the spp_address field is blank then
+ *                     delayed sack is disabled for the entire association. Note
+ *                     also that this field is mutually exclusive to
+ *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
+ *                     results.
+ *
+ *                     SPP_IPV6_FLOWLABEL:  Setting this flag enables the
+ *                     setting of the IPV6 flow label value.  The value is
+ *                     contained in the spp_ipv6_flowlabel field.
+ *                     Upon retrieval, this flag will be set to indicate that
+ *                     the spp_ipv6_flowlabel field has a valid value returned.
+ *                     If a specific destination address is set (in the
+ *                     spp_address field), then the value returned is that of
+ *                     the address.  If just an association is specified (and
+ *                     no address), then the association's default flow label
+ *                     is returned.  If neither an association nor a destination
+ *                     is specified, then the socket's default flow label is
+ *                     returned.  For non-IPv6 sockets, this flag will be left
+ *                     cleared.
+ *
+ *                     SPP_DSCP:  Setting this flag enables the setting of the
+ *                     Differentiated Services Code Point (DSCP) value
+ *                     associated with either the association or a specific
+ *                     address.  The value is obtained in the spp_dscp field.
+ *                     Upon retrieval, this flag will be set to indicate that
+ *                     the spp_dscp field has a valid value returned.  If a
+ *                     specific destination address is set when called (in the
+ *                     spp_address field), then that specific destination
+ *                     address's DSCP value is returned.  If just an association
+ *                     is specified, then the association's default DSCP is
+ *                     returned.  If neither an association nor a destination is
+ *                     specified, then the socket's default DSCP is returned.
+ *
+ *   spp_ipv6_flowlabel
+ *                   - This field is used in conjunction with the
+ *                     SPP_IPV6_FLOWLABEL flag and contains the IPv6 flow label.
+ *                     The 20 least significant bits are used for the flow
+ *                     label.  This setting has precedence over any IPv6-layer
+ *                     setting.
+ *
+ *   spp_dscp        - This field is used in conjunction with the SPP_DSCP flag
+ *                     and contains the DSCP.  The 6 most significant bits are
+ *                     used for the DSCP.  This setting has precedence over any
+ *                     IPv4- or IPv6- layer setting.
+ */
+static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
+				       struct sctp_transport   *trans,
+				       struct sctp_association *asoc,
+				       struct sctp_sock        *sp,
+				       int                      hb_change,
+				       int                      pmtud_change,
+				       int                      sackdelay_change)
+{
+	int error;
+
+	if (params->spp_flags & SPP_HB_DEMAND && trans) {
+		struct net *net = sock_net(trans->asoc->base.sk);
+
+		error = sctp_primitive_REQUESTHEARTBEAT(net, trans->asoc, trans);
+		if (error)
+			return error;
+	}
+
+	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
+	 * this field is ignored.  Note also that a value of zero indicates
+	 * the current setting should be left unchanged.
+	 */
+	if (params->spp_flags & SPP_HB_ENABLE) {
+
+		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
+		 * set.  This lets us use 0 value when this flag
+		 * is set.
+		 */
+		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
+			params->spp_hbinterval = 0;
+
+		if (params->spp_hbinterval ||
+		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
+			if (trans) {
+				trans->hbinterval =
+				    msecs_to_jiffies(params->spp_hbinterval);
+			} else if (asoc) {
+				asoc->hbinterval =
+				    msecs_to_jiffies(params->spp_hbinterval);
+			} else {
+				sp->hbinterval = params->spp_hbinterval;
+			}
+		}
+	}
+
+	if (hb_change) {
+		if (trans) {
+			trans->param_flags =
+				(trans->param_flags & ~SPP_HB) | hb_change;
+		} else if (asoc) {
+			asoc->param_flags =
+				(asoc->param_flags & ~SPP_HB) | hb_change;
+		} else {
+			sp->param_flags =
+				(sp->param_flags & ~SPP_HB) | hb_change;
+		}
+	}
+
+	/* When Path MTU discovery is disabled the value specified here will
+	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
+	 * include the flag SPP_PMTUD_DISABLE for this field to have any
+	 * effect).
+	 */
+	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
+		if (trans) {
+			trans->pathmtu = params->spp_pathmtu;
+			sctp_assoc_sync_pmtu(asoc);
+		} else if (asoc) {
+			sctp_assoc_set_pmtu(asoc, params->spp_pathmtu);
+		} else {
+			sp->pathmtu = params->spp_pathmtu;
+		}
+	}
+
+	if (pmtud_change) {
+		if (trans) {
+			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
+				(params->spp_flags & SPP_PMTUD_ENABLE);
+			trans->param_flags =
+				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
+			if (update) {
+				sctp_transport_pmtu(trans, sctp_opt2sk(sp));
+				sctp_assoc_sync_pmtu(asoc);
+			}
+		} else if (asoc) {
+			asoc->param_flags =
+				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
+		} else {
+			sp->param_flags =
+				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
+		}
+	}
+
+	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
+	 * value of this field is ignored.  Note also that a value of zero
+	 * indicates the current setting should be left unchanged.
+	 */
+	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
+		if (trans) {
+			trans->sackdelay =
+				msecs_to_jiffies(params->spp_sackdelay);
+		} else if (asoc) {
+			asoc->sackdelay =
+				msecs_to_jiffies(params->spp_sackdelay);
+		} else {
+			sp->sackdelay = params->spp_sackdelay;
+		}
+	}
+
+	if (sackdelay_change) {
+		if (trans) {
+			trans->param_flags =
+				(trans->param_flags & ~SPP_SACKDELAY) |
+				sackdelay_change;
+		} else if (asoc) {
+			asoc->param_flags =
+				(asoc->param_flags & ~SPP_SACKDELAY) |
+				sackdelay_change;
+		} else {
+			sp->param_flags =
+				(sp->param_flags & ~SPP_SACKDELAY) |
+				sackdelay_change;
+		}
+	}
+
+	/* Note that a value of zero indicates the current setting should be
+	   left unchanged.
+	 */
+	if (params->spp_pathmaxrxt) {
+		if (trans) {
+			trans->pathmaxrxt = params->spp_pathmaxrxt;
+		} else if (asoc) {
+			asoc->pathmaxrxt = params->spp_pathmaxrxt;
+		} else {
+			sp->pathmaxrxt = params->spp_pathmaxrxt;
+		}
+	}
+
+	if (params->spp_flags & SPP_IPV6_FLOWLABEL) {
+		if (trans) {
+			if (trans->ipaddr.sa.sa_family == AF_INET6) {
+				trans->flowlabel = params->spp_ipv6_flowlabel &
+						   SCTP_FLOWLABEL_VAL_MASK;
+				trans->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
+			}
+		} else if (asoc) {
+			struct sctp_transport *t;
+
+			list_for_each_entry(t, &asoc->peer.transport_addr_list,
+					    transports) {
+				if (t->ipaddr.sa.sa_family != AF_INET6)
+					continue;
+				t->flowlabel = params->spp_ipv6_flowlabel &
+					       SCTP_FLOWLABEL_VAL_MASK;
+				t->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
+			}
+			asoc->flowlabel = params->spp_ipv6_flowlabel &
+					  SCTP_FLOWLABEL_VAL_MASK;
+			asoc->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
+		} else if (sctp_opt2sk(sp)->sk_family == AF_INET6) {
+			sp->flowlabel = params->spp_ipv6_flowlabel &
+					SCTP_FLOWLABEL_VAL_MASK;
+			sp->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
+		}
+	}
+
+	if (params->spp_flags & SPP_DSCP) {
+		if (trans) {
+			trans->dscp = params->spp_dscp & SCTP_DSCP_VAL_MASK;
+			trans->dscp |= SCTP_DSCP_SET_MASK;
+		} else if (asoc) {
+			struct sctp_transport *t;
+
+			list_for_each_entry(t, &asoc->peer.transport_addr_list,
+					    transports) {
+				t->dscp = params->spp_dscp &
+					  SCTP_DSCP_VAL_MASK;
+				t->dscp |= SCTP_DSCP_SET_MASK;
+			}
+			asoc->dscp = params->spp_dscp & SCTP_DSCP_VAL_MASK;
+			asoc->dscp |= SCTP_DSCP_SET_MASK;
+		} else {
+			sp->dscp = params->spp_dscp & SCTP_DSCP_VAL_MASK;
+			sp->dscp |= SCTP_DSCP_SET_MASK;
+		}
+	}
+
+	return 0;
+}
+
+static int sctp_setsockopt_peer_addr_params(struct sock *sk,
+					    char __user *optval,
+					    unsigned int optlen)
+{
+	struct sctp_paddrparams  params;
+	struct sctp_transport   *trans = NULL;
+	struct sctp_association *asoc = NULL;
+	struct sctp_sock        *sp = sctp_sk(sk);
+	int error;
+	int hb_change, pmtud_change, sackdelay_change;
+
+	if (optlen == sizeof(params)) {
+		if (copy_from_user(&params, optval, optlen))
+			return -EFAULT;
+	} else if (optlen == ALIGN(offsetof(struct sctp_paddrparams,
+					    spp_ipv6_flowlabel), 4)) {
+		if (copy_from_user(&params, optval, optlen))
+			return -EFAULT;
+		if (params.spp_flags & (SPP_DSCP | SPP_IPV6_FLOWLABEL))
+			return -EINVAL;
+	} else {
+		return -EINVAL;
+	}
+
+	/* Validate flags and value parameters. */
+	hb_change        = params.spp_flags & SPP_HB;
+	pmtud_change     = params.spp_flags & SPP_PMTUD;
+	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
+
+	if (hb_change        == SPP_HB ||
+	    pmtud_change     == SPP_PMTUD ||
+	    sackdelay_change == SPP_SACKDELAY ||
+	    params.spp_sackdelay > 500 ||
+	    (params.spp_pathmtu &&
+	     params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
+		return -EINVAL;
+
+	/* If an address other than INADDR_ANY is specified, and
+	 * no transport is found, then the request is invalid.
+	 */
+	if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
+		trans = sctp_addr_id2transport(sk, &params.spp_address,
+					       params.spp_assoc_id);
+		if (!trans)
+			return -EINVAL;
+	}
+
+	/* Get association, if assoc_id != 0 and the socket is a one
+	 * to many style socket, and an association was not found, then
+	 * the id was invalid.
+	 */
+	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
+	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	/* Heartbeat demand can only be sent on a transport or
+	 * association, but not a socket.
+	 */
+	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
+		return -EINVAL;
+
+	/* Process parameters. */
+	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
+					    hb_change, pmtud_change,
+					    sackdelay_change);
+
+	if (error)
+		return error;
+
+	/* If changes are for association, also apply parameters to each
+	 * transport.
+	 */
+	if (!trans && asoc) {
+		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
+				transports) {
+			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
+						    hb_change, pmtud_change,
+						    sackdelay_change);
+		}
+	}
+
+	return 0;
+}
+
+static inline __u32 sctp_spp_sackdelay_enable(__u32 param_flags)
+{
+	return (param_flags & ~SPP_SACKDELAY) | SPP_SACKDELAY_ENABLE;
+}
+
+static inline __u32 sctp_spp_sackdelay_disable(__u32 param_flags)
+{
+	return (param_flags & ~SPP_SACKDELAY) | SPP_SACKDELAY_DISABLE;
+}
+
+/*
+ * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
+ *
+ * This option will effect the way delayed acks are performed.  This
+ * option allows you to get or set the delayed ack time, in
+ * milliseconds.  It also allows changing the delayed ack frequency.
+ * Changing the frequency to 1 disables the delayed sack algorithm.  If
+ * the assoc_id is 0, then this sets or gets the endpoints default
+ * values.  If the assoc_id field is non-zero, then the set or get
+ * effects the specified association for the one to many model (the
+ * assoc_id field is ignored by the one to one model).  Note that if
+ * sack_delay or sack_freq are 0 when setting this option, then the
+ * current values will remain unchanged.
+ *
+ * struct sctp_sack_info {
+ *     sctp_assoc_t            sack_assoc_id;
+ *     uint32_t                sack_delay;
+ *     uint32_t                sack_freq;
+ * };
+ *
+ * sack_assoc_id -  This parameter, indicates which association the user
+ *    is performing an action upon.  Note that if this field's value is
+ *    zero then the endpoints default value is changed (effecting future
+ *    associations only).
+ *
+ * sack_delay -  This parameter contains the number of milliseconds that
+ *    the user is requesting the delayed ACK timer be set to.  Note that
+ *    this value is defined in the standard to be between 200 and 500
+ *    milliseconds.
+ *
+ * sack_freq -  This parameter contains the number of packets that must
+ *    be received before a sack is sent without waiting for the delay
+ *    timer to expire.  The default value for this is 2, setting this
+ *    value to 1 will disable the delayed sack algorithm.
+ */
+
+static int sctp_setsockopt_delayed_ack(struct sock *sk,
+				       char __user *optval, unsigned int optlen)
+{
+	struct sctp_sack_info    params;
+	struct sctp_transport   *trans = NULL;
+	struct sctp_association *asoc = NULL;
+	struct sctp_sock        *sp = sctp_sk(sk);
+
+	if (optlen == sizeof(struct sctp_sack_info)) {
+		if (copy_from_user(&params, optval, optlen))
+			return -EFAULT;
+
+		if (params.sack_delay == 0 && params.sack_freq == 0)
+			return 0;
+	} else if (optlen == sizeof(struct sctp_assoc_value)) {
+		pr_warn_ratelimited(DEPRECATED
+				    "%s (pid %d) "
+				    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
+				    "Use struct sctp_sack_info instead\n",
+				    current->comm, task_pid_nr(current));
+		if (copy_from_user(&params, optval, optlen))
+			return -EFAULT;
+
+		if (params.sack_delay == 0)
+			params.sack_freq = 1;
+		else
+			params.sack_freq = 0;
+	} else
+		return -EINVAL;
+
+	/* Validate value parameter. */
+	if (params.sack_delay > 500)
+		return -EINVAL;
+
+	/* Get association, if sack_assoc_id != 0 and the socket is a one
+	 * to many style socket, and an association was not found, then
+	 * the id was invalid.
+	 */
+	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
+	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	if (params.sack_delay) {
+		if (asoc) {
+			asoc->sackdelay =
+				msecs_to_jiffies(params.sack_delay);
+			asoc->param_flags =
+				sctp_spp_sackdelay_enable(asoc->param_flags);
+		} else {
+			sp->sackdelay = params.sack_delay;
+			sp->param_flags =
+				sctp_spp_sackdelay_enable(sp->param_flags);
+		}
+	}
+
+	if (params.sack_freq == 1) {
+		if (asoc) {
+			asoc->param_flags =
+				sctp_spp_sackdelay_disable(asoc->param_flags);
+		} else {
+			sp->param_flags =
+				sctp_spp_sackdelay_disable(sp->param_flags);
+		}
+	} else if (params.sack_freq > 1) {
+		if (asoc) {
+			asoc->sackfreq = params.sack_freq;
+			asoc->param_flags =
+				sctp_spp_sackdelay_enable(asoc->param_flags);
+		} else {
+			sp->sackfreq = params.sack_freq;
+			sp->param_flags =
+				sctp_spp_sackdelay_enable(sp->param_flags);
+		}
+	}
+
+	/* If change is for association, also apply to each transport. */
+	if (asoc) {
+		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
+				transports) {
+			if (params.sack_delay) {
+				trans->sackdelay =
+					msecs_to_jiffies(params.sack_delay);
+				trans->param_flags =
+					sctp_spp_sackdelay_enable(trans->param_flags);
+			}
+			if (params.sack_freq == 1) {
+				trans->param_flags =
+					sctp_spp_sackdelay_disable(trans->param_flags);
+			} else if (params.sack_freq > 1) {
+				trans->sackfreq = params.sack_freq;
+				trans->param_flags =
+					sctp_spp_sackdelay_enable(trans->param_flags);
+			}
+		}
+	}
+
+	return 0;
+}
+
+/* 7.1.3 Initialization Parameters (SCTP_INITMSG)
+ *
+ * Applications can specify protocol parameters for the default association
+ * initialization.  The option name argument to setsockopt() and getsockopt()
+ * is SCTP_INITMSG.
+ *
+ * Setting initialization parameters is effective only on an unconnected
+ * socket (for UDP-style sockets only future associations are effected
+ * by the change).  With TCP-style sockets, this option is inherited by
+ * sockets derived from a listener socket.
+ */
+static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, unsigned int optlen)
+{
+	struct sctp_initmsg sinit;
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	if (optlen != sizeof(struct sctp_initmsg))
+		return -EINVAL;
+	if (copy_from_user(&sinit, optval, optlen))
+		return -EFAULT;
+
+	if (sinit.sinit_num_ostreams)
+		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
+	if (sinit.sinit_max_instreams)
+		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
+	if (sinit.sinit_max_attempts)
+		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
+	if (sinit.sinit_max_init_timeo)
+		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
+
+	return 0;
+}
+
+/*
+ * 7.1.14 Set default send parameters (SCTP_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 __user *optval,
+					      unsigned int optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_association *asoc;
+	struct sctp_sndrcvinfo info;
+
+	if (optlen != sizeof(info))
+		return -EINVAL;
+	if (copy_from_user(&info, optval, optlen))
+		return -EFAULT;
+	if (info.sinfo_flags &
+	    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
+	      SCTP_ABORT | SCTP_EOF))
+		return -EINVAL;
+
+	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
+	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+	if (asoc) {
+		asoc->default_stream = info.sinfo_stream;
+		asoc->default_flags = info.sinfo_flags;
+		asoc->default_ppid = info.sinfo_ppid;
+		asoc->default_context = info.sinfo_context;
+		asoc->default_timetolive = info.sinfo_timetolive;
+	} else {
+		sp->default_stream = info.sinfo_stream;
+		sp->default_flags = info.sinfo_flags;
+		sp->default_ppid = info.sinfo_ppid;
+		sp->default_context = info.sinfo_context;
+		sp->default_timetolive = info.sinfo_timetolive;
+	}
+
+	return 0;
+}
+
+/* RFC6458, Section 8.1.31. Set/get Default Send Parameters
+ * (SCTP_DEFAULT_SNDINFO)
+ */
+static int sctp_setsockopt_default_sndinfo(struct sock *sk,
+					   char __user *optval,
+					   unsigned int optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_association *asoc;
+	struct sctp_sndinfo info;
+
+	if (optlen != sizeof(info))
+		return -EINVAL;
+	if (copy_from_user(&info, optval, optlen))
+		return -EFAULT;
+	if (info.snd_flags &
+	    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
+	      SCTP_ABORT | SCTP_EOF))
+		return -EINVAL;
+
+	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
+	if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+	if (asoc) {
+		asoc->default_stream = info.snd_sid;
+		asoc->default_flags = info.snd_flags;
+		asoc->default_ppid = info.snd_ppid;
+		asoc->default_context = info.snd_context;
+	} else {
+		sp->default_stream = info.snd_sid;
+		sp->default_flags = info.snd_flags;
+		sp->default_ppid = info.snd_ppid;
+		sp->default_context = info.snd_context;
+	}
+
+	return 0;
+}
+
+/* 7.1.10 Set Primary Address (SCTP_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_primary_addr(struct sock *sk, char __user *optval,
+					unsigned int optlen)
+{
+	struct sctp_prim prim;
+	struct sctp_transport *trans;
+	struct sctp_af *af;
+	int err;
+
+	if (optlen != sizeof(struct sctp_prim))
+		return -EINVAL;
+
+	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
+		return -EFAULT;
+
+	/* Allow security module to validate address but need address len. */
+	af = sctp_get_af_specific(prim.ssp_addr.ss_family);
+	if (!af)
+		return -EINVAL;
+
+	err = security_sctp_bind_connect(sk, SCTP_PRIMARY_ADDR,
+					 (struct sockaddr *)&prim.ssp_addr,
+					 af->sockaddr_len);
+	if (err)
+		return err;
+
+	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
+	if (!trans)
+		return -EINVAL;
+
+	sctp_assoc_set_primary(trans->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 __user *optval,
+				   unsigned int optlen)
+{
+	int val;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
+	return 0;
+}
+
+/*
+ *
+ * 7.1.1 SCTP_RTOINFO
+ *
+ * The protocol parameters used to initialize and bound retransmission
+ * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
+ * and modify these parameters.
+ * All parameters are time values, in milliseconds.  A value of 0, when
+ * modifying the parameters, indicates that the current value should not
+ * be changed.
+ *
+ */
+static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, unsigned int optlen)
+{
+	struct sctp_rtoinfo rtoinfo;
+	struct sctp_association *asoc;
+	unsigned long rto_min, rto_max;
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	if (optlen != sizeof (struct sctp_rtoinfo))
+		return -EINVAL;
+
+	if (copy_from_user(&rtoinfo, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
+
+	/* Set the values to the specific association */
+	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	rto_max = rtoinfo.srto_max;
+	rto_min = rtoinfo.srto_min;
+
+	if (rto_max)
+		rto_max = asoc ? msecs_to_jiffies(rto_max) : rto_max;
+	else
+		rto_max = asoc ? asoc->rto_max : sp->rtoinfo.srto_max;
+
+	if (rto_min)
+		rto_min = asoc ? msecs_to_jiffies(rto_min) : rto_min;
+	else
+		rto_min = asoc ? asoc->rto_min : sp->rtoinfo.srto_min;
+
+	if (rto_min > rto_max)
+		return -EINVAL;
+
+	if (asoc) {
+		if (rtoinfo.srto_initial != 0)
+			asoc->rto_initial =
+				msecs_to_jiffies(rtoinfo.srto_initial);
+		asoc->rto_max = rto_max;
+		asoc->rto_min = rto_min;
+	} else {
+		/* If there is no association or the association-id = 0
+		 * set the values to the endpoint.
+		 */
+		if (rtoinfo.srto_initial != 0)
+			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
+		sp->rtoinfo.srto_max = rto_max;
+		sp->rtoinfo.srto_min = rto_min;
+	}
+
+	return 0;
+}
+
+/*
+ *
+ * 7.1.2 SCTP_ASSOCINFO
+ *
+ * This option is used to tune the maximum retransmission attempts
+ * of the association.
+ * Returns an error if the new association retransmission value is
+ * greater than the sum of the retransmission value  of the peer.
+ * See [SCTP] for more information.
+ *
+ */
+static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, unsigned int optlen)
+{
+
+	struct sctp_assocparams assocparams;
+	struct sctp_association *asoc;
+
+	if (optlen != sizeof(struct sctp_assocparams))
+		return -EINVAL;
+	if (copy_from_user(&assocparams, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
+
+	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	/* Set the values to the specific association */
+	if (asoc) {
+		if (assocparams.sasoc_asocmaxrxt != 0) {
+			__u32 path_sum = 0;
+			int   paths = 0;
+			struct sctp_transport *peer_addr;
+
+			list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
+					transports) {
+				path_sum += peer_addr->pathmaxrxt;
+				paths++;
+			}
+
+			/* Only validate asocmaxrxt if we have more than
+			 * one path/transport.  We do this because path
+			 * retransmissions are only counted when we have more
+			 * then one path.
+			 */
+			if (paths > 1 &&
+			    assocparams.sasoc_asocmaxrxt > path_sum)
+				return -EINVAL;
+
+			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
+		}
+
+		if (assocparams.sasoc_cookie_life != 0)
+			asoc->cookie_life = ms_to_ktime(assocparams.sasoc_cookie_life);
+	} else {
+		/* Set the values to the endpoint */
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		if (assocparams.sasoc_asocmaxrxt != 0)
+			sp->assocparams.sasoc_asocmaxrxt =
+						assocparams.sasoc_asocmaxrxt;
+		if (assocparams.sasoc_cookie_life != 0)
+			sp->assocparams.sasoc_cookie_life =
+						assocparams.sasoc_cookie_life;
+	}
+	return 0;
+}
+
+/*
+ * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
+ *
+ * This socket option is a boolean flag which turns on or off mapped V4
+ * addresses.  If this option is turned on and the socket is type
+ * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
+ * If this option is turned off, then no mapping will be done of V4
+ * addresses and a user will receive both PF_INET6 and PF_INET type
+ * addresses on the socket.
+ */
+static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsigned int optlen)
+{
+	int val;
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+	if (val)
+		sp->v4mapped = 1;
+	else
+		sp->v4mapped = 0;
+
+	return 0;
+}
+
+/*
+ * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
+ * This option will get or set the maximum size to put in any outgoing
+ * SCTP DATA chunk.  If a message is larger than this size it will be
+ * fragmented by SCTP into the specified size.  Note that the underlying
+ * SCTP implementation may fragment into smaller sized chunks when the
+ * PMTU of the underlying association is smaller than the value set by
+ * the user.  The default value for this option is '0' which indicates
+ * the user is NOT limiting fragmentation and only the PMTU will effect
+ * SCTP's choice of DATA chunk size.  Note also that values set larger
+ * than the maximum size of an IP datagram will effectively let SCTP
+ * control fragmentation (i.e. the same as setting this option to 0).
+ *
+ * The following structure is used to access and modify this parameter:
+ *
+ * struct sctp_assoc_value {
+ *   sctp_assoc_t assoc_id;
+ *   uint32_t assoc_value;
+ * };
+ *
+ * assoc_id:  This parameter is ignored for one-to-one style sockets.
+ *    For one-to-many style sockets this parameter indicates which
+ *    association the user is performing an action upon.  Note that if
+ *    this field's value is zero then the endpoints default value is
+ *    changed (effecting future associations only).
+ * assoc_value:  This parameter specifies the maximum size in bytes.
+ */
+static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int val;
+
+	if (optlen == sizeof(int)) {
+		pr_warn_ratelimited(DEPRECATED
+				    "%s (pid %d) "
+				    "Use of int in maxseg socket option.\n"
+				    "Use struct sctp_assoc_value instead\n",
+				    current->comm, task_pid_nr(current));
+		if (copy_from_user(&val, optval, optlen))
+			return -EFAULT;
+		params.assoc_id = 0;
+	} else if (optlen == sizeof(struct sctp_assoc_value)) {
+		if (copy_from_user(&params, optval, optlen))
+			return -EFAULT;
+		val = params.assoc_value;
+	} else {
+		return -EINVAL;
+	}
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+
+	if (val) {
+		int min_len, max_len;
+		__u16 datasize = asoc ? sctp_datachk_len(&asoc->stream) :
+				 sizeof(struct sctp_data_chunk);
+
+		min_len = sctp_min_frag_point(sp, datasize);
+		max_len = SCTP_MAX_CHUNK_LEN - datasize;
+
+		if (val < min_len || val > max_len)
+			return -EINVAL;
+	}
+
+	if (asoc) {
+		asoc->user_frag = val;
+		sctp_assoc_update_frag_point(asoc);
+	} else {
+		if (params.assoc_id && sctp_style(sk, UDP))
+			return -EINVAL;
+		sp->user_frag = val;
+	}
+
+	return 0;
+}
+
+
+/*
+ *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
+ *
+ *   Requests that the peer mark the enclosed address as the association
+ *   primary. The enclosed address must be one of the association's
+ *   locally bound addresses. The following structure is used to make a
+ *   set primary request:
+ */
+static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
+					     unsigned int optlen)
+{
+	struct net *net = sock_net(sk);
+	struct sctp_sock	*sp;
+	struct sctp_association	*asoc = NULL;
+	struct sctp_setpeerprim	prim;
+	struct sctp_chunk	*chunk;
+	struct sctp_af		*af;
+	int 			err;
+
+	sp = sctp_sk(sk);
+
+	if (!net->sctp.addip_enable)
+		return -EPERM;
+
+	if (optlen != sizeof(struct sctp_setpeerprim))
+		return -EINVAL;
+
+	if (copy_from_user(&prim, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	if (!asoc->peer.asconf_capable)
+		return -EPERM;
+
+	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
+		return -EPERM;
+
+	if (!sctp_state(asoc, ESTABLISHED))
+		return -ENOTCONN;
+
+	af = sctp_get_af_specific(prim.sspp_addr.ss_family);
+	if (!af)
+		return -EINVAL;
+
+	if (!af->addr_valid((union sctp_addr *)&prim.sspp_addr, sp, NULL))
+		return -EADDRNOTAVAIL;
+
+	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
+		return -EADDRNOTAVAIL;
+
+	/* Allow security module to validate address. */
+	err = security_sctp_bind_connect(sk, SCTP_SET_PEER_PRIMARY_ADDR,
+					 (struct sockaddr *)&prim.sspp_addr,
+					 af->sockaddr_len);
+	if (err)
+		return err;
+
+	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
+	chunk = sctp_make_asconf_set_prim(asoc,
+					  (union sctp_addr *)&prim.sspp_addr);
+	if (!chunk)
+		return -ENOMEM;
+
+	err = sctp_send_asconf(asoc, chunk);
+
+	pr_debug("%s: we set peer primary addr primitively\n", __func__);
+
+	return err;
+}
+
+static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
+					    unsigned int optlen)
+{
+	struct sctp_setadaptation adaptation;
+
+	if (optlen != sizeof(struct sctp_setadaptation))
+		return -EINVAL;
+	if (copy_from_user(&adaptation, optval, optlen))
+		return -EFAULT;
+
+	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
+
+	return 0;
+}
+
+/*
+ * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
+ *
+ * The context field in the sctp_sndrcvinfo structure is normally only
+ * used when a failed message is retrieved holding the value that was
+ * sent down on the actual send call.  This option allows the setting of
+ * a default context on an association basis that will be received on
+ * reading messages from the peer.  This is especially helpful in the
+ * one-2-many model for an application to keep some reference to an
+ * internal state machine that is processing messages on the
+ * association.  Note that the setting of this value only effects
+ * received messages from the peer and does not effect the value that is
+ * saved with outbound messages.
+ */
+static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
+				   unsigned int optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_sock *sp;
+	struct sctp_association *asoc;
+
+	if (optlen != sizeof(struct sctp_assoc_value))
+		return -EINVAL;
+	if (copy_from_user(&params, optval, optlen))
+		return -EFAULT;
+
+	sp = sctp_sk(sk);
+
+	if (params.assoc_id != 0) {
+		asoc = sctp_id2assoc(sk, params.assoc_id);
+		if (!asoc)
+			return -EINVAL;
+		asoc->default_rcv_context = params.assoc_value;
+	} else {
+		sp->default_rcv_context = params.assoc_value;
+	}
+
+	return 0;
+}
+
+/*
+ * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
+ *
+ * This options will at a minimum specify if the implementation is doing
+ * fragmented interleave.  Fragmented interleave, for a one to many
+ * socket, is when subsequent calls to receive a message may return
+ * parts of messages from different associations.  Some implementations
+ * may allow you to turn this value on or off.  If so, when turned off,
+ * no fragment interleave will occur (which will cause a head of line
+ * blocking amongst multiple associations sharing the same one to many
+ * socket).  When this option is turned on, then each receive call may
+ * come from a different association (thus the user must receive data
+ * with the extended calls (e.g. sctp_recvmsg) to keep track of which
+ * association each receive belongs to.
+ *
+ * This option takes a boolean value.  A non-zero value indicates that
+ * fragmented interleave is on.  A value of zero indicates that
+ * fragmented interleave is off.
+ *
+ * Note that it is important that an implementation that allows this
+ * option to be turned on, have it off by default.  Otherwise an unaware
+ * application using the one to many model may become confused and act
+ * incorrectly.
+ */
+static int sctp_setsockopt_fragment_interleave(struct sock *sk,
+					       char __user *optval,
+					       unsigned int optlen)
+{
+	int val;
+
+	if (optlen != sizeof(int))
+		return -EINVAL;
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->frag_interleave = !!val;
+
+	if (!sctp_sk(sk)->frag_interleave)
+		sctp_sk(sk)->strm_interleave = 0;
+
+	return 0;
+}
+
+/*
+ * 8.1.21.  Set or Get the SCTP Partial Delivery Point
+ *       (SCTP_PARTIAL_DELIVERY_POINT)
+ *
+ * This option will set or get the SCTP partial delivery point.  This
+ * point is the size of a message where the partial delivery API will be
+ * invoked to help free up rwnd space for the peer.  Setting this to a
+ * lower value will cause partial deliveries to happen more often.  The
+ * calls argument is an integer that sets or gets the partial delivery
+ * point.  Note also that the call will fail if the user attempts to set
+ * this value larger than the socket receive buffer size.
+ *
+ * Note that any single message having a length smaller than or equal to
+ * the SCTP partial delivery point will be delivered in one single read
+ * call as long as the user provided buffer is large enough to hold the
+ * message.
+ */
+static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
+						  char __user *optval,
+						  unsigned int optlen)
+{
+	u32 val;
+
+	if (optlen != sizeof(u32))
+		return -EINVAL;
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+
+	/* Note: We double the receive buffer from what the user sets
+	 * it to be, also initial rwnd is based on rcvbuf/2.
+	 */
+	if (val > (sk->sk_rcvbuf >> 1))
+		return -EINVAL;
+
+	sctp_sk(sk)->pd_point = val;
+
+	return 0; /* is this the right error code? */
+}
+
+/*
+ * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
+ *
+ * This option will allow a user to change the maximum burst of packets
+ * that can be emitted by this association.  Note that the default value
+ * is 4, and some implementations may restrict this setting so that it
+ * can only be lowered.
+ *
+ * NOTE: This text doesn't seem right.  Do this on a socket basis with
+ * future associations inheriting the socket value.
+ */
+static int sctp_setsockopt_maxburst(struct sock *sk,
+				    char __user *optval,
+				    unsigned int optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_sock *sp;
+	struct sctp_association *asoc;
+	int val;
+	int assoc_id = 0;
+
+	if (optlen == sizeof(int)) {
+		pr_warn_ratelimited(DEPRECATED
+				    "%s (pid %d) "
+				    "Use of int in max_burst socket option deprecated.\n"
+				    "Use struct sctp_assoc_value instead\n",
+				    current->comm, task_pid_nr(current));
+		if (copy_from_user(&val, optval, optlen))
+			return -EFAULT;
+	} else if (optlen == sizeof(struct sctp_assoc_value)) {
+		if (copy_from_user(&params, optval, optlen))
+			return -EFAULT;
+		val = params.assoc_value;
+		assoc_id = params.assoc_id;
+	} else
+		return -EINVAL;
+
+	sp = sctp_sk(sk);
+
+	if (assoc_id != 0) {
+		asoc = sctp_id2assoc(sk, assoc_id);
+		if (!asoc)
+			return -EINVAL;
+		asoc->max_burst = val;
+	} else
+		sp->max_burst = val;
+
+	return 0;
+}
+
+/*
+ * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
+ *
+ * This set option adds a chunk type that the user is requesting to be
+ * received only in an authenticated way.  Changes to the list of chunks
+ * will only effect future associations on the socket.
+ */
+static int sctp_setsockopt_auth_chunk(struct sock *sk,
+				      char __user *optval,
+				      unsigned int optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_authchunk val;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (optlen != sizeof(struct sctp_authchunk))
+		return -EINVAL;
+	if (copy_from_user(&val, optval, optlen))
+		return -EFAULT;
+
+	switch (val.sauth_chunk) {
+	case SCTP_CID_INIT:
+	case SCTP_CID_INIT_ACK:
+	case SCTP_CID_SHUTDOWN_COMPLETE:
+	case SCTP_CID_AUTH:
+		return -EINVAL;
+	}
+
+	/* add this chunk id to the endpoint */
+	return sctp_auth_ep_add_chunkid(ep, val.sauth_chunk);
+}
+
+/*
+ * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
+ *
+ * This option gets or sets the list of HMAC algorithms that the local
+ * endpoint requires the peer to use.
+ */
+static int sctp_setsockopt_hmac_ident(struct sock *sk,
+				      char __user *optval,
+				      unsigned int optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_hmacalgo *hmacs;
+	u32 idents;
+	int err;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (optlen < sizeof(struct sctp_hmacalgo))
+		return -EINVAL;
+	optlen = min_t(unsigned int, optlen, sizeof(struct sctp_hmacalgo) +
+					     SCTP_AUTH_NUM_HMACS * sizeof(u16));
+
+	hmacs = memdup_user(optval, optlen);
+	if (IS_ERR(hmacs))
+		return PTR_ERR(hmacs);
+
+	idents = hmacs->shmac_num_idents;
+	if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
+	    (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	err = sctp_auth_ep_set_hmacs(ep, hmacs);
+out:
+	kfree(hmacs);
+	return err;
+}
+
+/*
+ * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
+ *
+ * This option will set a shared secret key which is used to build an
+ * association shared key.
+ */
+static int sctp_setsockopt_auth_key(struct sock *sk,
+				    char __user *optval,
+				    unsigned int optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_authkey *authkey;
+	struct sctp_association *asoc;
+	int ret;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (optlen <= sizeof(struct sctp_authkey))
+		return -EINVAL;
+	/* authkey->sca_keylength is u16, so optlen can't be bigger than
+	 * this.
+	 */
+	optlen = min_t(unsigned int, optlen, USHRT_MAX +
+					     sizeof(struct sctp_authkey));
+
+	authkey = memdup_user(optval, optlen);
+	if (IS_ERR(authkey))
+		return PTR_ERR(authkey);
+
+	if (authkey->sca_keylength > optlen - sizeof(struct sctp_authkey)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
+	if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = sctp_auth_set_key(ep, asoc, authkey);
+out:
+	kzfree(authkey);
+	return ret;
+}
+
+/*
+ * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
+ *
+ * This option will get or set the active shared key to be used to build
+ * the association shared key.
+ */
+static int sctp_setsockopt_active_key(struct sock *sk,
+				      char __user *optval,
+				      unsigned int optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_authkeyid val;
+	struct sctp_association *asoc;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (optlen != sizeof(struct sctp_authkeyid))
+		return -EINVAL;
+	if (copy_from_user(&val, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
+	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	return sctp_auth_set_active_key(ep, asoc, val.scact_keynumber);
+}
+
+/*
+ * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
+ *
+ * This set option will delete a shared secret key from use.
+ */
+static int sctp_setsockopt_del_key(struct sock *sk,
+				   char __user *optval,
+				   unsigned int optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_authkeyid val;
+	struct sctp_association *asoc;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (optlen != sizeof(struct sctp_authkeyid))
+		return -EINVAL;
+	if (copy_from_user(&val, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
+	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	return sctp_auth_del_key_id(ep, asoc, val.scact_keynumber);
+
+}
+
+/*
+ * 8.3.4  Deactivate a Shared Key (SCTP_AUTH_DEACTIVATE_KEY)
+ *
+ * This set option will deactivate a shared secret key.
+ */
+static int sctp_setsockopt_deactivate_key(struct sock *sk, char __user *optval,
+					  unsigned int optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_authkeyid val;
+	struct sctp_association *asoc;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (optlen != sizeof(struct sctp_authkeyid))
+		return -EINVAL;
+	if (copy_from_user(&val, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
+	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	return sctp_auth_deact_key_id(ep, asoc, val.scact_keynumber);
+}
+
+/*
+ * 8.1.23 SCTP_AUTO_ASCONF
+ *
+ * This option will enable or disable the use of the automatic generation of
+ * ASCONF chunks to add and delete addresses to an existing association.  Note
+ * that this option has two caveats namely: a) it only affects sockets that
+ * are bound to all addresses available to the SCTP stack, and b) the system
+ * administrator may have an overriding control that turns the ASCONF feature
+ * off no matter what setting the socket option may have.
+ * This option expects an integer boolean flag, where a non-zero value turns on
+ * the option, and a zero value turns off the option.
+ * Note. In this implementation, socket operation overrides default parameter
+ * being set by sysctl as well as FreeBSD implementation
+ */
+static int sctp_setsockopt_auto_asconf(struct sock *sk, char __user *optval,
+					unsigned int optlen)
+{
+	int val;
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+	if (!sctp_is_ep_boundall(sk) && val)
+		return -EINVAL;
+	if ((val && sp->do_auto_asconf) || (!val && !sp->do_auto_asconf))
+		return 0;
+
+	spin_lock_bh(&sock_net(sk)->sctp.addr_wq_lock);
+	if (val == 0 && sp->do_auto_asconf) {
+		list_del(&sp->auto_asconf_list);
+		sp->do_auto_asconf = 0;
+	} else if (val && !sp->do_auto_asconf) {
+		list_add_tail(&sp->auto_asconf_list,
+		    &sock_net(sk)->sctp.auto_asconf_splist);
+		sp->do_auto_asconf = 1;
+	}
+	spin_unlock_bh(&sock_net(sk)->sctp.addr_wq_lock);
+	return 0;
+}
+
+/*
+ * SCTP_PEER_ADDR_THLDS
+ *
+ * This option allows us to alter the partially failed threshold for one or all
+ * transports in an association.  See Section 6.1 of:
+ * http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt
+ */
+static int sctp_setsockopt_paddr_thresholds(struct sock *sk,
+					    char __user *optval,
+					    unsigned int optlen)
+{
+	struct sctp_paddrthlds val;
+	struct sctp_transport *trans;
+	struct sctp_association *asoc;
+
+	if (optlen < sizeof(struct sctp_paddrthlds))
+		return -EINVAL;
+	if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval,
+			   sizeof(struct sctp_paddrthlds)))
+		return -EFAULT;
+
+
+	if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
+		asoc = sctp_id2assoc(sk, val.spt_assoc_id);
+		if (!asoc)
+			return -ENOENT;
+		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
+				    transports) {
+			if (val.spt_pathmaxrxt)
+				trans->pathmaxrxt = val.spt_pathmaxrxt;
+			trans->pf_retrans = val.spt_pathpfthld;
+		}
+
+		if (val.spt_pathmaxrxt)
+			asoc->pathmaxrxt = val.spt_pathmaxrxt;
+		asoc->pf_retrans = val.spt_pathpfthld;
+	} else {
+		trans = sctp_addr_id2transport(sk, &val.spt_address,
+					       val.spt_assoc_id);
+		if (!trans)
+			return -ENOENT;
+
+		if (val.spt_pathmaxrxt)
+			trans->pathmaxrxt = val.spt_pathmaxrxt;
+		trans->pf_retrans = val.spt_pathpfthld;
+	}
+
+	return 0;
+}
+
+static int sctp_setsockopt_recvrcvinfo(struct sock *sk,
+				       char __user *optval,
+				       unsigned int optlen)
+{
+	int val;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+	if (get_user(val, (int __user *) optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->recvrcvinfo = (val == 0) ? 0 : 1;
+
+	return 0;
+}
+
+static int sctp_setsockopt_recvnxtinfo(struct sock *sk,
+				       char __user *optval,
+				       unsigned int optlen)
+{
+	int val;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+	if (get_user(val, (int __user *) optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->recvnxtinfo = (val == 0) ? 0 : 1;
+
+	return 0;
+}
+
+static int sctp_setsockopt_pr_supported(struct sock *sk,
+					char __user *optval,
+					unsigned int optlen)
+{
+	struct sctp_assoc_value params;
+
+	if (optlen != sizeof(params))
+		return -EINVAL;
+
+	if (copy_from_user(&params, optval, optlen))
+		return -EFAULT;
+
+	sctp_sk(sk)->ep->prsctp_enable = !!params.assoc_value;
+
+	return 0;
+}
+
+static int sctp_setsockopt_default_prinfo(struct sock *sk,
+					  char __user *optval,
+					  unsigned int optlen)
+{
+	struct sctp_default_prinfo info;
+	struct sctp_association *asoc;
+	int retval = -EINVAL;
+
+	if (optlen != sizeof(info))
+		goto out;
+
+	if (copy_from_user(&info, optval, sizeof(info))) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (info.pr_policy & ~SCTP_PR_SCTP_MASK)
+		goto out;
+
+	if (info.pr_policy == SCTP_PR_SCTP_NONE)
+		info.pr_value = 0;
+
+	asoc = sctp_id2assoc(sk, info.pr_assoc_id);
+	if (asoc) {
+		SCTP_PR_SET_POLICY(asoc->default_flags, info.pr_policy);
+		asoc->default_timetolive = info.pr_value;
+	} else if (!info.pr_assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		SCTP_PR_SET_POLICY(sp->default_flags, info.pr_policy);
+		sp->default_timetolive = info.pr_value;
+	} else {
+		goto out;
+	}
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_setsockopt_reconfig_supported(struct sock *sk,
+					      char __user *optval,
+					      unsigned int optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EINVAL;
+
+	if (optlen != sizeof(params))
+		goto out;
+
+	if (copy_from_user(&params, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (asoc) {
+		asoc->reconf_enable = !!params.assoc_value;
+	} else if (!params.assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		sp->ep->reconf_enable = !!params.assoc_value;
+	} else {
+		goto out;
+	}
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_setsockopt_enable_strreset(struct sock *sk,
+					   char __user *optval,
+					   unsigned int optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EINVAL;
+
+	if (optlen != sizeof(params))
+		goto out;
+
+	if (copy_from_user(&params, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (params.assoc_value & (~SCTP_ENABLE_STRRESET_MASK))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (asoc) {
+		asoc->strreset_enable = params.assoc_value;
+	} else if (!params.assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		sp->ep->strreset_enable = params.assoc_value;
+	} else {
+		goto out;
+	}
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_setsockopt_reset_streams(struct sock *sk,
+					 char __user *optval,
+					 unsigned int optlen)
+{
+	struct sctp_reset_streams *params;
+	struct sctp_association *asoc;
+	int retval = -EINVAL;
+
+	if (optlen < sizeof(*params))
+		return -EINVAL;
+	/* srs_number_streams is u16, so optlen can't be bigger than this. */
+	optlen = min_t(unsigned int, optlen, USHRT_MAX +
+					     sizeof(__u16) * sizeof(*params));
+
+	params = memdup_user(optval, optlen);
+	if (IS_ERR(params))
+		return PTR_ERR(params);
+
+	if (params->srs_number_streams * sizeof(__u16) >
+	    optlen - sizeof(*params))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params->srs_assoc_id);
+	if (!asoc)
+		goto out;
+
+	retval = sctp_send_reset_streams(asoc, params);
+
+out:
+	kfree(params);
+	return retval;
+}
+
+static int sctp_setsockopt_reset_assoc(struct sock *sk,
+				       char __user *optval,
+				       unsigned int optlen)
+{
+	struct sctp_association *asoc;
+	sctp_assoc_t associd;
+	int retval = -EINVAL;
+
+	if (optlen != sizeof(associd))
+		goto out;
+
+	if (copy_from_user(&associd, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	asoc = sctp_id2assoc(sk, associd);
+	if (!asoc)
+		goto out;
+
+	retval = sctp_send_reset_assoc(asoc);
+
+out:
+	return retval;
+}
+
+static int sctp_setsockopt_add_streams(struct sock *sk,
+				       char __user *optval,
+				       unsigned int optlen)
+{
+	struct sctp_association *asoc;
+	struct sctp_add_streams params;
+	int retval = -EINVAL;
+
+	if (optlen != sizeof(params))
+		goto out;
+
+	if (copy_from_user(&params, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	asoc = sctp_id2assoc(sk, params.sas_assoc_id);
+	if (!asoc)
+		goto out;
+
+	retval = sctp_send_add_streams(asoc, &params);
+
+out:
+	return retval;
+}
+
+static int sctp_setsockopt_scheduler(struct sock *sk,
+				     char __user *optval,
+				     unsigned int optlen)
+{
+	struct sctp_association *asoc;
+	struct sctp_assoc_value params;
+	int retval = -EINVAL;
+
+	if (optlen < sizeof(params))
+		goto out;
+
+	optlen = sizeof(params);
+	if (copy_from_user(&params, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (params.assoc_value > SCTP_SS_MAX)
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (!asoc)
+		goto out;
+
+	retval = sctp_sched_set_sched(asoc, params.assoc_value);
+
+out:
+	return retval;
+}
+
+static int sctp_setsockopt_scheduler_value(struct sock *sk,
+					   char __user *optval,
+					   unsigned int optlen)
+{
+	struct sctp_association *asoc;
+	struct sctp_stream_value params;
+	int retval = -EINVAL;
+
+	if (optlen < sizeof(params))
+		goto out;
+
+	optlen = sizeof(params);
+	if (copy_from_user(&params, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (!asoc)
+		goto out;
+
+	retval = sctp_sched_set_value(asoc, params.stream_id,
+				      params.stream_value, GFP_KERNEL);
+
+out:
+	return retval;
+}
+
+static int sctp_setsockopt_interleaving_supported(struct sock *sk,
+						  char __user *optval,
+						  unsigned int optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct net *net = sock_net(sk);
+	struct sctp_assoc_value params;
+	int retval = -EINVAL;
+
+	if (optlen < sizeof(params))
+		goto out;
+
+	optlen = sizeof(params);
+	if (copy_from_user(&params, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (params.assoc_id)
+		goto out;
+
+	if (!net->sctp.intl_enable || !sp->frag_interleave) {
+		retval = -EPERM;
+		goto out;
+	}
+
+	sp->strm_interleave = !!params.assoc_value;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_setsockopt_reuse_port(struct sock *sk, char __user *optval,
+				      unsigned int optlen)
+{
+	int val;
+
+	if (!sctp_style(sk, TCP))
+		return -EOPNOTSUPP;
+
+	if (sctp_sk(sk)->ep->base.bind_addr.port)
+		return -EFAULT;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->reuse = !!val;
+
+	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 __user *optval,
+ *                    int __user *optlen);
+ *   ret = setsockopt(int sd, int level, int optname, const void __user *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.
+ */
+static int sctp_setsockopt(struct sock *sk, int level, int optname,
+			   char __user *optval, unsigned int optlen)
+{
+	int retval = 0;
+
+	pr_debug("%s: sk:%p, optname:%d\n", __func__, 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;
+	}
+
+	lock_sock(sk);
+
+	switch (optname) {
+	case SCTP_SOCKOPT_BINDX_ADD:
+		/* 'optlen' is the size of the addresses buffer. */
+		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
+					       optlen, SCTP_BINDX_ADD_ADDR);
+		break;
+
+	case SCTP_SOCKOPT_BINDX_REM:
+		/* 'optlen' is the size of the addresses buffer. */
+		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
+					       optlen, SCTP_BINDX_REM_ADDR);
+		break;
+
+	case SCTP_SOCKOPT_CONNECTX_OLD:
+		/* 'optlen' is the size of the addresses buffer. */
+		retval = sctp_setsockopt_connectx_old(sk,
+					    (struct sockaddr __user *)optval,
+					    optlen);
+		break;
+
+	case SCTP_SOCKOPT_CONNECTX:
+		/* 'optlen' is the size of the addresses buffer. */
+		retval = sctp_setsockopt_connectx(sk,
+					    (struct sockaddr __user *)optval,
+					    optlen);
+		break;
+
+	case SCTP_DISABLE_FRAGMENTS:
+		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
+		break;
+
+	case SCTP_EVENTS:
+		retval = sctp_setsockopt_events(sk, optval, optlen);
+		break;
+
+	case SCTP_AUTOCLOSE:
+		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
+		break;
+
+	case SCTP_PEER_ADDR_PARAMS:
+		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
+		break;
+
+	case SCTP_DELAYED_SACK:
+		retval = sctp_setsockopt_delayed_ack(sk, optval, optlen);
+		break;
+	case SCTP_PARTIAL_DELIVERY_POINT:
+		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
+		break;
+
+	case SCTP_INITMSG:
+		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
+		break;
+	case SCTP_DEFAULT_SEND_PARAM:
+		retval = sctp_setsockopt_default_send_param(sk, optval,
+							    optlen);
+		break;
+	case SCTP_DEFAULT_SNDINFO:
+		retval = sctp_setsockopt_default_sndinfo(sk, optval, optlen);
+		break;
+	case SCTP_PRIMARY_ADDR:
+		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
+		break;
+	case SCTP_SET_PEER_PRIMARY_ADDR:
+		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
+		break;
+	case SCTP_NODELAY:
+		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
+		break;
+	case SCTP_RTOINFO:
+		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
+		break;
+	case SCTP_ASSOCINFO:
+		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
+		break;
+	case SCTP_I_WANT_MAPPED_V4_ADDR:
+		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
+		break;
+	case SCTP_MAXSEG:
+		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
+		break;
+	case SCTP_ADAPTATION_LAYER:
+		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
+		break;
+	case SCTP_CONTEXT:
+		retval = sctp_setsockopt_context(sk, optval, optlen);
+		break;
+	case SCTP_FRAGMENT_INTERLEAVE:
+		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
+		break;
+	case SCTP_MAX_BURST:
+		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
+		break;
+	case SCTP_AUTH_CHUNK:
+		retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
+		break;
+	case SCTP_HMAC_IDENT:
+		retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
+		break;
+	case SCTP_AUTH_KEY:
+		retval = sctp_setsockopt_auth_key(sk, optval, optlen);
+		break;
+	case SCTP_AUTH_ACTIVE_KEY:
+		retval = sctp_setsockopt_active_key(sk, optval, optlen);
+		break;
+	case SCTP_AUTH_DELETE_KEY:
+		retval = sctp_setsockopt_del_key(sk, optval, optlen);
+		break;
+	case SCTP_AUTH_DEACTIVATE_KEY:
+		retval = sctp_setsockopt_deactivate_key(sk, optval, optlen);
+		break;
+	case SCTP_AUTO_ASCONF:
+		retval = sctp_setsockopt_auto_asconf(sk, optval, optlen);
+		break;
+	case SCTP_PEER_ADDR_THLDS:
+		retval = sctp_setsockopt_paddr_thresholds(sk, optval, optlen);
+		break;
+	case SCTP_RECVRCVINFO:
+		retval = sctp_setsockopt_recvrcvinfo(sk, optval, optlen);
+		break;
+	case SCTP_RECVNXTINFO:
+		retval = sctp_setsockopt_recvnxtinfo(sk, optval, optlen);
+		break;
+	case SCTP_PR_SUPPORTED:
+		retval = sctp_setsockopt_pr_supported(sk, optval, optlen);
+		break;
+	case SCTP_DEFAULT_PRINFO:
+		retval = sctp_setsockopt_default_prinfo(sk, optval, optlen);
+		break;
+	case SCTP_RECONFIG_SUPPORTED:
+		retval = sctp_setsockopt_reconfig_supported(sk, optval, optlen);
+		break;
+	case SCTP_ENABLE_STREAM_RESET:
+		retval = sctp_setsockopt_enable_strreset(sk, optval, optlen);
+		break;
+	case SCTP_RESET_STREAMS:
+		retval = sctp_setsockopt_reset_streams(sk, optval, optlen);
+		break;
+	case SCTP_RESET_ASSOC:
+		retval = sctp_setsockopt_reset_assoc(sk, optval, optlen);
+		break;
+	case SCTP_ADD_STREAMS:
+		retval = sctp_setsockopt_add_streams(sk, optval, optlen);
+		break;
+	case SCTP_STREAM_SCHEDULER:
+		retval = sctp_setsockopt_scheduler(sk, optval, optlen);
+		break;
+	case SCTP_STREAM_SCHEDULER_VALUE:
+		retval = sctp_setsockopt_scheduler_value(sk, optval, optlen);
+		break;
+	case SCTP_INTERLEAVING_SUPPORTED:
+		retval = sctp_setsockopt_interleaving_supported(sk, optval,
+								optlen);
+		break;
+	case SCTP_REUSE_PORT:
+		retval = sctp_setsockopt_reuse_port(sk, optval, optlen);
+		break;
+	default:
+		retval = -ENOPROTOOPT;
+		break;
+	}
+
+	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.
+ */
+static int sctp_connect(struct sock *sk, struct sockaddr *addr,
+			int addr_len, int flags)
+{
+	struct sctp_af *af;
+	int err = -EINVAL;
+
+	lock_sock(sk);
+
+	pr_debug("%s: sk:%p, sockaddr:%p, addr_len:%d\n", __func__, sk,
+		 addr, addr_len);
+
+	/* Validate addr_len before calling common connect/connectx routine. */
+	af = sctp_get_af_specific(addr->sa_family);
+	if (af && addr_len >= af->sockaddr_len)
+		err = __sctp_connect(sk, addr, af->sockaddr_len, flags, NULL);
+
+	release_sock(sk);
+	return err;
+}
+
+int sctp_inet_connect(struct socket *sock, struct sockaddr *uaddr,
+		      int addr_len, int flags)
+{
+	if (addr_len < sizeof(uaddr->sa_family))
+		return -EINVAL;
+
+	if (uaddr->sa_family == AF_UNSPEC)
+		return -EOPNOTSUPP;
+
+	return sctp_connect(sock->sk, uaddr, addr_len, flags);
+}
+
+/* FIXME: Write comments. */
+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.
+ */
+static struct sock *sctp_accept(struct sock *sk, int flags, int *err, bool kern)
+{
+	struct sctp_sock *sp;
+	struct sctp_endpoint *ep;
+	struct sock *newsk = NULL;
+	struct sctp_association *asoc;
+	long timeo;
+	int error = 0;
+
+	lock_sock(sk);
+
+	sp = sctp_sk(sk);
+	ep = sp->ep;
+
+	if (!sctp_style(sk, TCP)) {
+		error = -EOPNOTSUPP;
+		goto out;
+	}
+
+	if (!sctp_sstate(sk, LISTENING)) {
+		error = -EINVAL;
+		goto out;
+	}
+
+	timeo = sock_rcvtimeo(sk, 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, kern);
+	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:
+	release_sock(sk);
+	*err = error;
+	return newsk;
+}
+
+/* The SCTP ioctl handler. */
+static int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
+{
+	int rc = -ENOTCONN;
+
+	lock_sock(sk);
+
+	/*
+	 * SEQPACKET-style sockets in LISTENING state are valid, for
+	 * SCTP, so only discard TCP-style sockets in LISTENING state.
+	 */
+	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
+		goto out;
+
+	switch (cmd) {
+	case SIOCINQ: {
+		struct sk_buff *skb;
+		unsigned int amount = 0;
+
+		skb = skb_peek(&sk->sk_receive_queue);
+		if (skb != NULL) {
+			/*
+			 * We will only return the amount of this packet since
+			 * that is all that will be read.
+			 */
+			amount = skb->len;
+		}
+		rc = put_user(amount, (int __user *)arg);
+		break;
+	}
+	default:
+		rc = -ENOIOCTLCMD;
+		break;
+	}
+out:
+	release_sock(sk);
+	return rc;
+}
+
+/* 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.
+ */
+static int sctp_init_sock(struct sock *sk)
+{
+	struct net *net = sock_net(sk);
+	struct sctp_sock *sp;
+
+	pr_debug("%s: sk:%p\n", __func__, sk);
+
+	sp = sctp_sk(sk);
+
+	/* Initialize the SCTP per socket area.  */
+	switch (sk->sk_type) {
+	case SOCK_SEQPACKET:
+		sp->type = SCTP_SOCKET_UDP;
+		break;
+	case SOCK_STREAM:
+		sp->type = SCTP_SOCKET_TCP;
+		break;
+	default:
+		return -ESOCKTNOSUPPORT;
+	}
+
+	sk->sk_gso_type = SKB_GSO_SCTP;
+
+	/* Initialize default send parameters. These parameters can be
+	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
+	 */
+	sp->default_stream = 0;
+	sp->default_ppid = 0;
+	sp->default_flags = 0;
+	sp->default_context = 0;
+	sp->default_timetolive = 0;
+
+	sp->default_rcv_context = 0;
+	sp->max_burst = net->sctp.max_burst;
+
+	sp->sctp_hmac_alg = net->sctp.sctp_hmac_alg;
+
+	/* 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   = sctp_max_outstreams;
+	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
+	sp->initmsg.sinit_max_attempts   = net->sctp.max_retrans_init;
+	sp->initmsg.sinit_max_init_timeo = net->sctp.rto_max;
+
+	/* Initialize default RTO related parameters.  These parameters can
+	 * be modified for with the SCTP_RTOINFO socket option.
+	 */
+	sp->rtoinfo.srto_initial = net->sctp.rto_initial;
+	sp->rtoinfo.srto_max     = net->sctp.rto_max;
+	sp->rtoinfo.srto_min     = net->sctp.rto_min;
+
+	/* Initialize default association related parameters. These parameters
+	 * can be modified with the SCTP_ASSOCINFO socket option.
+	 */
+	sp->assocparams.sasoc_asocmaxrxt = net->sctp.max_retrans_association;
+	sp->assocparams.sasoc_number_peer_destinations = 0;
+	sp->assocparams.sasoc_peer_rwnd = 0;
+	sp->assocparams.sasoc_local_rwnd = 0;
+	sp->assocparams.sasoc_cookie_life = net->sctp.valid_cookie_life;
+
+	/* Initialize default event subscriptions. By default, all the
+	 * options are off.
+	 */
+	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
+
+	/* Default Peer Address Parameters.  These defaults can
+	 * be modified via SCTP_PEER_ADDR_PARAMS
+	 */
+	sp->hbinterval  = net->sctp.hb_interval;
+	sp->pathmaxrxt  = net->sctp.max_retrans_path;
+	sp->pathmtu     = 0; /* allow default discovery */
+	sp->sackdelay   = net->sctp.sack_timeout;
+	sp->sackfreq	= 2;
+	sp->param_flags = SPP_HB_ENABLE |
+			  SPP_PMTUD_ENABLE |
+			  SPP_SACKDELAY_ENABLE;
+
+	/* If enabled no SCTP message fragmentation will be performed.
+	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
+	 */
+	sp->disable_fragments = 0;
+
+	/* Enable Nagle algorithm by default.  */
+	sp->nodelay           = 0;
+
+	sp->recvrcvinfo = 0;
+	sp->recvnxtinfo = 0;
+
+	/* Enable by default. */
+	sp->v4mapped          = 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;
+
+	/* User specified fragmentation limit. */
+	sp->user_frag         = 0;
+
+	sp->adaptation_ind = 0;
+
+	sp->pf = sctp_get_pf_specific(sk->sk_family);
+
+	/* Control variables for partial data delivery. */
+	atomic_set(&sp->pd_mode, 0);
+	skb_queue_head_init(&sp->pd_lobby);
+	sp->frag_interleave = 0;
+
+	/* 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.
+	 */
+	sp->ep = sctp_endpoint_new(sk, GFP_KERNEL);
+	if (!sp->ep)
+		return -ENOMEM;
+
+	sp->hmac = NULL;
+
+	sk->sk_destruct = sctp_destruct_sock;
+
+	SCTP_DBG_OBJCNT_INC(sock);
+
+	local_bh_disable();
+	sk_sockets_allocated_inc(sk);
+	sock_prot_inuse_add(net, sk->sk_prot, 1);
+
+	local_bh_enable();
+
+	return 0;
+}
+
+/* Cleanup any SCTP per socket resources. Must be called with
+ * sock_net(sk)->sctp.addr_wq_lock held if sp->do_auto_asconf is true
+ */
+static void sctp_destroy_sock(struct sock *sk)
+{
+	struct sctp_sock *sp;
+
+	pr_debug("%s: sk:%p\n", __func__, sk);
+
+	/* Release our hold on the endpoint. */
+	sp = sctp_sk(sk);
+	/* This could happen during socket init, thus we bail out
+	 * early, since the rest of the below is not setup either.
+	 */
+	if (sp->ep == NULL)
+		return;
+
+	if (sp->do_auto_asconf) {
+		sp->do_auto_asconf = 0;
+		list_del(&sp->auto_asconf_list);
+	}
+	sctp_endpoint_free(sp->ep);
+	local_bh_disable();
+	sk_sockets_allocated_dec(sk);
+	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
+	local_bh_enable();
+}
+
+/* Triggered when there are no references on the socket anymore */
+static void sctp_destruct_sock(struct sock *sk)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	/* Free up the HMAC transform. */
+	crypto_free_shash(sp->hmac);
+
+	inet_sock_destruct(sk);
+}
+
+/* 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.
+ */
+static void sctp_shutdown(struct sock *sk, int how)
+{
+	struct net *net = sock_net(sk);
+	struct sctp_endpoint *ep;
+
+	if (!sctp_style(sk, TCP))
+		return;
+
+	ep = sctp_sk(sk)->ep;
+	if (how & SEND_SHUTDOWN && !list_empty(&ep->asocs)) {
+		struct sctp_association *asoc;
+
+		inet_sk_set_state(sk, SCTP_SS_CLOSING);
+		asoc = list_entry(ep->asocs.next,
+				  struct sctp_association, asocs);
+		sctp_primitive_SHUTDOWN(net, asoc, NULL);
+	}
+}
+
+int sctp_get_sctp_info(struct sock *sk, struct sctp_association *asoc,
+		       struct sctp_info *info)
+{
+	struct sctp_transport *prim;
+	struct list_head *pos;
+	int mask;
+
+	memset(info, 0, sizeof(*info));
+	if (!asoc) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		info->sctpi_s_autoclose = sp->autoclose;
+		info->sctpi_s_adaptation_ind = sp->adaptation_ind;
+		info->sctpi_s_pd_point = sp->pd_point;
+		info->sctpi_s_nodelay = sp->nodelay;
+		info->sctpi_s_disable_fragments = sp->disable_fragments;
+		info->sctpi_s_v4mapped = sp->v4mapped;
+		info->sctpi_s_frag_interleave = sp->frag_interleave;
+		info->sctpi_s_type = sp->type;
+
+		return 0;
+	}
+
+	info->sctpi_tag = asoc->c.my_vtag;
+	info->sctpi_state = asoc->state;
+	info->sctpi_rwnd = asoc->a_rwnd;
+	info->sctpi_unackdata = asoc->unack_data;
+	info->sctpi_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
+	info->sctpi_instrms = asoc->stream.incnt;
+	info->sctpi_outstrms = asoc->stream.outcnt;
+	list_for_each(pos, &asoc->base.inqueue.in_chunk_list)
+		info->sctpi_inqueue++;
+	list_for_each(pos, &asoc->outqueue.out_chunk_list)
+		info->sctpi_outqueue++;
+	info->sctpi_overall_error = asoc->overall_error_count;
+	info->sctpi_max_burst = asoc->max_burst;
+	info->sctpi_maxseg = asoc->frag_point;
+	info->sctpi_peer_rwnd = asoc->peer.rwnd;
+	info->sctpi_peer_tag = asoc->c.peer_vtag;
+
+	mask = asoc->peer.ecn_capable << 1;
+	mask = (mask | asoc->peer.ipv4_address) << 1;
+	mask = (mask | asoc->peer.ipv6_address) << 1;
+	mask = (mask | asoc->peer.hostname_address) << 1;
+	mask = (mask | asoc->peer.asconf_capable) << 1;
+	mask = (mask | asoc->peer.prsctp_capable) << 1;
+	mask = (mask | asoc->peer.auth_capable);
+	info->sctpi_peer_capable = mask;
+	mask = asoc->peer.sack_needed << 1;
+	mask = (mask | asoc->peer.sack_generation) << 1;
+	mask = (mask | asoc->peer.zero_window_announced);
+	info->sctpi_peer_sack = mask;
+
+	info->sctpi_isacks = asoc->stats.isacks;
+	info->sctpi_osacks = asoc->stats.osacks;
+	info->sctpi_opackets = asoc->stats.opackets;
+	info->sctpi_ipackets = asoc->stats.ipackets;
+	info->sctpi_rtxchunks = asoc->stats.rtxchunks;
+	info->sctpi_outofseqtsns = asoc->stats.outofseqtsns;
+	info->sctpi_idupchunks = asoc->stats.idupchunks;
+	info->sctpi_gapcnt = asoc->stats.gapcnt;
+	info->sctpi_ouodchunks = asoc->stats.ouodchunks;
+	info->sctpi_iuodchunks = asoc->stats.iuodchunks;
+	info->sctpi_oodchunks = asoc->stats.oodchunks;
+	info->sctpi_iodchunks = asoc->stats.iodchunks;
+	info->sctpi_octrlchunks = asoc->stats.octrlchunks;
+	info->sctpi_ictrlchunks = asoc->stats.ictrlchunks;
+
+	prim = asoc->peer.primary_path;
+	memcpy(&info->sctpi_p_address, &prim->ipaddr, sizeof(prim->ipaddr));
+	info->sctpi_p_state = prim->state;
+	info->sctpi_p_cwnd = prim->cwnd;
+	info->sctpi_p_srtt = prim->srtt;
+	info->sctpi_p_rto = jiffies_to_msecs(prim->rto);
+	info->sctpi_p_hbinterval = prim->hbinterval;
+	info->sctpi_p_pathmaxrxt = prim->pathmaxrxt;
+	info->sctpi_p_sackdelay = jiffies_to_msecs(prim->sackdelay);
+	info->sctpi_p_ssthresh = prim->ssthresh;
+	info->sctpi_p_partial_bytes_acked = prim->partial_bytes_acked;
+	info->sctpi_p_flight_size = prim->flight_size;
+	info->sctpi_p_error = prim->error_count;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sctp_get_sctp_info);
+
+/* use callback to avoid exporting the core structure */
+void sctp_transport_walk_start(struct rhashtable_iter *iter)
+{
+	rhltable_walk_enter(&sctp_transport_hashtable, iter);
+
+	rhashtable_walk_start(iter);
+}
+
+void sctp_transport_walk_stop(struct rhashtable_iter *iter)
+{
+	rhashtable_walk_stop(iter);
+	rhashtable_walk_exit(iter);
+}
+
+struct sctp_transport *sctp_transport_get_next(struct net *net,
+					       struct rhashtable_iter *iter)
+{
+	struct sctp_transport *t;
+
+	t = rhashtable_walk_next(iter);
+	for (; t; t = rhashtable_walk_next(iter)) {
+		if (IS_ERR(t)) {
+			if (PTR_ERR(t) == -EAGAIN)
+				continue;
+			break;
+		}
+
+		if (!sctp_transport_hold(t))
+			continue;
+
+		if (net_eq(sock_net(t->asoc->base.sk), net) &&
+		    t->asoc->peer.primary_path == t)
+			break;
+
+		sctp_transport_put(t);
+	}
+
+	return t;
+}
+
+struct sctp_transport *sctp_transport_get_idx(struct net *net,
+					      struct rhashtable_iter *iter,
+					      int pos)
+{
+	struct sctp_transport *t;
+
+	if (!pos)
+		return SEQ_START_TOKEN;
+
+	while ((t = sctp_transport_get_next(net, iter)) && !IS_ERR(t)) {
+		if (!--pos)
+			break;
+		sctp_transport_put(t);
+	}
+
+	return t;
+}
+
+int sctp_for_each_endpoint(int (*cb)(struct sctp_endpoint *, void *),
+			   void *p) {
+	int err = 0;
+	int hash = 0;
+	struct sctp_ep_common *epb;
+	struct sctp_hashbucket *head;
+
+	for (head = sctp_ep_hashtable; hash < sctp_ep_hashsize;
+	     hash++, head++) {
+		read_lock_bh(&head->lock);
+		sctp_for_each_hentry(epb, &head->chain) {
+			err = cb(sctp_ep(epb), p);
+			if (err)
+				break;
+		}
+		read_unlock_bh(&head->lock);
+	}
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(sctp_for_each_endpoint);
+
+int sctp_transport_lookup_process(int (*cb)(struct sctp_transport *, void *),
+				  struct net *net,
+				  const union sctp_addr *laddr,
+				  const union sctp_addr *paddr, void *p)
+{
+	struct sctp_transport *transport;
+	int err;
+
+	rcu_read_lock();
+	transport = sctp_addrs_lookup_transport(net, laddr, paddr);
+	rcu_read_unlock();
+	if (!transport)
+		return -ENOENT;
+
+	err = cb(transport, p);
+	sctp_transport_put(transport);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(sctp_transport_lookup_process);
+
+int sctp_transport_traverse_process(sctp_callback_t cb, sctp_callback_t cb_done,
+				    struct net *net, int *pos, void *p)
+{
+	struct rhashtable_iter hti;
+	struct sctp_transport *tsp;
+	struct sctp_endpoint *ep;
+	int ret;
+
+again:
+	ret = 0;
+	sctp_transport_walk_start(&hti);
+
+	tsp = sctp_transport_get_idx(net, &hti, *pos + 1);
+	for (; !IS_ERR_OR_NULL(tsp); tsp = sctp_transport_get_next(net, &hti)) {
+		ep = tsp->asoc->ep;
+		if (sctp_endpoint_hold(ep)) { /* asoc can be peeled off */
+			ret = cb(ep, tsp, p);
+			if (ret)
+				break;
+			sctp_endpoint_put(ep);
+		}
+		(*pos)++;
+		sctp_transport_put(tsp);
+	}
+	sctp_transport_walk_stop(&hti);
+
+	if (ret) {
+		if (cb_done && !cb_done(ep, tsp, p)) {
+			(*pos)++;
+			sctp_endpoint_put(ep);
+			sctp_transport_put(tsp);
+			goto again;
+		}
+		sctp_endpoint_put(ep);
+		sctp_transport_put(tsp);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sctp_transport_traverse_process);
+
+/* 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 __user *optval,
+				       int __user *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;
+	}
+
+	len = sizeof(status);
+	if (copy_from_user(&status, optval, len)) {
+		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 = sctp_assoc_to_state(asoc);
+	status.sstat_rwnd =  asoc->peer.rwnd;
+	status.sstat_unackdata = asoc->unack_data;
+
+	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
+	status.sstat_instrms = asoc->stream.incnt;
+	status.sstat_outstrms = asoc->stream.outcnt;
+	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,
+			transport->af_specific->sockaddr_len);
+	/* Map ipv4 address into v4-mapped-on-v6 address.  */
+	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
+		(union sctp_addr *)&status.sstat_primary.spinfo_address);
+	status.sstat_primary.spinfo_state = transport->state;
+	status.sstat_primary.spinfo_cwnd = transport->cwnd;
+	status.sstat_primary.spinfo_srtt = transport->srtt;
+	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
+	status.sstat_primary.spinfo_mtu = transport->pathmtu;
+
+	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
+		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
+
+	if (put_user(len, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	pr_debug("%s: len:%d, state:%d, rwnd:%d, assoc_id:%d\n",
+		 __func__, 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;
+}
+
+
+/* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
+ *
+ * Applications can retrieve information about a specific peer address
+ * of an association, including its reachability state, congestion
+ * window, and retransmission timer values.  This information is
+ * read-only.
+ */
+static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
+					  char __user *optval,
+					  int __user *optlen)
+{
+	struct sctp_paddrinfo pinfo;
+	struct sctp_transport *transport;
+	int retval = 0;
+
+	if (len < sizeof(pinfo)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(pinfo);
+	if (copy_from_user(&pinfo, optval, len)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
+					   pinfo.spinfo_assoc_id);
+	if (!transport)
+		return -EINVAL;
+
+	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
+	pinfo.spinfo_state = transport->state;
+	pinfo.spinfo_cwnd = transport->cwnd;
+	pinfo.spinfo_srtt = transport->srtt;
+	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
+	pinfo.spinfo_mtu = transport->pathmtu;
+
+	if (pinfo.spinfo_state == SCTP_UNKNOWN)
+		pinfo.spinfo_state = SCTP_ACTIVE;
+
+	if (put_user(len, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (copy_to_user(optval, &pinfo, len)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+out:
+	return retval;
+}
+
+/* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
+ *
+ * This option is a on/off flag.  If enabled no SCTP message
+ * fragmentation will be performed.  Instead if a message being sent
+ * exceeds the current PMTU size, the message will NOT be sent and
+ * instead a error will be indicated to the user.
+ */
+static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
+					char __user *optval, int __user *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;
+}
+
+/* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
+ *
+ * This socket option is used to specify various notifications and
+ * ancillary data the user wishes to receive.
+ */
+static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
+				  int __user *optlen)
+{
+	if (len == 0)
+		return -EINVAL;
+	if (len > sizeof(struct sctp_event_subscribe))
+		len = sizeof(struct sctp_event_subscribe);
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
+		return -EFAULT;
+	return 0;
+}
+
+/* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
+ *
+ * This socket option is applicable to the UDP-style socket only.  When
+ * set it will cause associations that are idle for more than the
+ * specified number of seconds to automatically close.  An association
+ * being idle is defined an association that has NOT sent or received
+ * user data.  The special value of '0' indicates that no automatic
+ * close of any associations should be performed.  The option expects an
+ * integer defining the number of seconds of idle time before an
+ * association is closed.
+ */
+static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
+{
+	/* Applicable to UDP-style socket only */
+	if (sctp_style(sk, TCP))
+		return -EOPNOTSUPP;
+	if (len < sizeof(int))
+		return -EINVAL;
+	len = sizeof(int);
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (put_user(sctp_sk(sk)->autoclose, (int __user *)optval))
+		return -EFAULT;
+	return 0;
+}
+
+/* Helper routine to branch off an association to a new socket.  */
+int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp)
+{
+	struct sctp_association *asoc = sctp_id2assoc(sk, id);
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct socket *sock;
+	int err = 0;
+
+	/* Do not peel off from one netns to another one. */
+	if (!net_eq(current->nsproxy->net_ns, sock_net(sk)))
+		return -EINVAL;
+
+	if (!asoc)
+		return -EINVAL;
+
+	/* An association cannot be branched off from an already peeled-off
+	 * socket, nor is this supported for tcp style sockets.
+	 */
+	if (!sctp_style(sk, UDP))
+		return -EINVAL;
+
+	/* Create a new socket.  */
+	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
+	if (err < 0)
+		return err;
+
+	sctp_copy_sock(sock->sk, sk, asoc);
+
+	/* Make peeled-off sockets more like 1-1 accepted sockets.
+	 * Set the daddr and initialize id to something more random and also
+	 * copy over any ip options.
+	 */
+	sp->pf->to_sk_daddr(&asoc->peer.primary_addr, sock->sk);
+	sp->pf->copy_ip_options(sk, sock->sk);
+
+	/* 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;
+}
+EXPORT_SYMBOL(sctp_do_peeloff);
+
+static int sctp_getsockopt_peeloff_common(struct sock *sk, sctp_peeloff_arg_t *peeloff,
+					  struct file **newfile, unsigned flags)
+{
+	struct socket *newsock;
+	int retval;
+
+	retval = sctp_do_peeloff(sk, peeloff->associd, &newsock);
+	if (retval < 0)
+		goto out;
+
+	/* Map the socket to an unused fd that can be returned to the user.  */
+	retval = get_unused_fd_flags(flags & SOCK_CLOEXEC);
+	if (retval < 0) {
+		sock_release(newsock);
+		goto out;
+	}
+
+	*newfile = sock_alloc_file(newsock, 0, NULL);
+	if (IS_ERR(*newfile)) {
+		put_unused_fd(retval);
+		retval = PTR_ERR(*newfile);
+		*newfile = NULL;
+		return retval;
+	}
+
+	pr_debug("%s: sk:%p, newsk:%p, sd:%d\n", __func__, sk, newsock->sk,
+		 retval);
+
+	peeloff->sd = retval;
+
+	if (flags & SOCK_NONBLOCK)
+		(*newfile)->f_flags |= O_NONBLOCK;
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
+{
+	sctp_peeloff_arg_t peeloff;
+	struct file *newfile = NULL;
+	int retval = 0;
+
+	if (len < sizeof(sctp_peeloff_arg_t))
+		return -EINVAL;
+	len = sizeof(sctp_peeloff_arg_t);
+	if (copy_from_user(&peeloff, optval, len))
+		return -EFAULT;
+
+	retval = sctp_getsockopt_peeloff_common(sk, &peeloff, &newfile, 0);
+	if (retval < 0)
+		goto out;
+
+	/* Return the fd mapped to the new socket.  */
+	if (put_user(len, optlen)) {
+		fput(newfile);
+		put_unused_fd(retval);
+		return -EFAULT;
+	}
+
+	if (copy_to_user(optval, &peeloff, len)) {
+		fput(newfile);
+		put_unused_fd(retval);
+		return -EFAULT;
+	}
+	fd_install(retval, newfile);
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_peeloff_flags(struct sock *sk, int len,
+					 char __user *optval, int __user *optlen)
+{
+	sctp_peeloff_flags_arg_t peeloff;
+	struct file *newfile = NULL;
+	int retval = 0;
+
+	if (len < sizeof(sctp_peeloff_flags_arg_t))
+		return -EINVAL;
+	len = sizeof(sctp_peeloff_flags_arg_t);
+	if (copy_from_user(&peeloff, optval, len))
+		return -EFAULT;
+
+	retval = sctp_getsockopt_peeloff_common(sk, &peeloff.p_arg,
+						&newfile, peeloff.flags);
+	if (retval < 0)
+		goto out;
+
+	/* Return the fd mapped to the new socket.  */
+	if (put_user(len, optlen)) {
+		fput(newfile);
+		put_unused_fd(retval);
+		return -EFAULT;
+	}
+
+	if (copy_to_user(optval, &peeloff, len)) {
+		fput(newfile);
+		put_unused_fd(retval);
+		return -EFAULT;
+	}
+	fd_install(retval, newfile);
+out:
+	return retval;
+}
+
+/* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
+ *
+ * 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 following structure is used to access and modify an
+ * address's parameters:
+ *
+ *  struct sctp_paddrparams {
+ *     sctp_assoc_t            spp_assoc_id;
+ *     struct sockaddr_storage spp_address;
+ *     uint32_t                spp_hbinterval;
+ *     uint16_t                spp_pathmaxrxt;
+ *     uint32_t                spp_pathmtu;
+ *     uint32_t                spp_sackdelay;
+ *     uint32_t                spp_flags;
+ * };
+ *
+ *   spp_assoc_id    - (one-to-many style socket) This is filled in the
+ *                     application, and identifies the association for
+ *                     this query.
+ *   spp_address     - This specifies which address is of interest.
+ *   spp_hbinterval  - This contains the value of the heartbeat interval,
+ *                     in milliseconds.  If a  value of zero
+ *                     is present in this field then no changes are to
+ *                     be made to this parameter.
+ *   spp_pathmaxrxt  - This contains the maximum number of
+ *                     retransmissions before this address shall be
+ *                     considered unreachable. If a  value of zero
+ *                     is present in this field then no changes are to
+ *                     be made to this parameter.
+ *   spp_pathmtu     - When Path MTU discovery is disabled the value
+ *                     specified here will be the "fixed" path mtu.
+ *                     Note that if the spp_address field is empty
+ *                     then all associations on this address will
+ *                     have this fixed path mtu set upon them.
+ *
+ *   spp_sackdelay   - When delayed sack is enabled, this value specifies
+ *                     the number of milliseconds that sacks will be delayed
+ *                     for. This value will apply to all addresses of an
+ *                     association if the spp_address field is empty. Note
+ *                     also, that if delayed sack is enabled and this
+ *                     value is set to 0, no change is made to the last
+ *                     recorded delayed sack timer value.
+ *
+ *   spp_flags       - These flags are used to control various features
+ *                     on an association. The flag field may contain
+ *                     zero or more of the following options.
+ *
+ *                     SPP_HB_ENABLE  - Enable heartbeats on the
+ *                     specified address. Note that if the address
+ *                     field is empty all addresses for the association
+ *                     have heartbeats enabled upon them.
+ *
+ *                     SPP_HB_DISABLE - Disable heartbeats on the
+ *                     speicifed address. Note that if the address
+ *                     field is empty all addresses for the association
+ *                     will have their heartbeats disabled. Note also
+ *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
+ *                     mutually exclusive, only one of these two should
+ *                     be specified. Enabling both fields will have
+ *                     undetermined results.
+ *
+ *                     SPP_HB_DEMAND - Request a user initiated heartbeat
+ *                     to be made immediately.
+ *
+ *                     SPP_PMTUD_ENABLE - This field will enable PMTU
+ *                     discovery upon the specified address. Note that
+ *                     if the address feild is empty then all addresses
+ *                     on the association are effected.
+ *
+ *                     SPP_PMTUD_DISABLE - This field will disable PMTU
+ *                     discovery upon the specified address. Note that
+ *                     if the address feild is empty then all addresses
+ *                     on the association are effected. Not also that
+ *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
+ *                     exclusive. Enabling both will have undetermined
+ *                     results.
+ *
+ *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
+ *                     on delayed sack. The time specified in spp_sackdelay
+ *                     is used to specify the sack delay for this address. Note
+ *                     that if spp_address is empty then all addresses will
+ *                     enable delayed sack and take on the sack delay
+ *                     value specified in spp_sackdelay.
+ *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
+ *                     off delayed sack. If the spp_address field is blank then
+ *                     delayed sack is disabled for the entire association. Note
+ *                     also that this field is mutually exclusive to
+ *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
+ *                     results.
+ *
+ *                     SPP_IPV6_FLOWLABEL:  Setting this flag enables the
+ *                     setting of the IPV6 flow label value.  The value is
+ *                     contained in the spp_ipv6_flowlabel field.
+ *                     Upon retrieval, this flag will be set to indicate that
+ *                     the spp_ipv6_flowlabel field has a valid value returned.
+ *                     If a specific destination address is set (in the
+ *                     spp_address field), then the value returned is that of
+ *                     the address.  If just an association is specified (and
+ *                     no address), then the association's default flow label
+ *                     is returned.  If neither an association nor a destination
+ *                     is specified, then the socket's default flow label is
+ *                     returned.  For non-IPv6 sockets, this flag will be left
+ *                     cleared.
+ *
+ *                     SPP_DSCP:  Setting this flag enables the setting of the
+ *                     Differentiated Services Code Point (DSCP) value
+ *                     associated with either the association or a specific
+ *                     address.  The value is obtained in the spp_dscp field.
+ *                     Upon retrieval, this flag will be set to indicate that
+ *                     the spp_dscp field has a valid value returned.  If a
+ *                     specific destination address is set when called (in the
+ *                     spp_address field), then that specific destination
+ *                     address's DSCP value is returned.  If just an association
+ *                     is specified, then the association's default DSCP is
+ *                     returned.  If neither an association nor a destination is
+ *                     specified, then the socket's default DSCP is returned.
+ *
+ *   spp_ipv6_flowlabel
+ *                   - This field is used in conjunction with the
+ *                     SPP_IPV6_FLOWLABEL flag and contains the IPv6 flow label.
+ *                     The 20 least significant bits are used for the flow
+ *                     label.  This setting has precedence over any IPv6-layer
+ *                     setting.
+ *
+ *   spp_dscp        - This field is used in conjunction with the SPP_DSCP flag
+ *                     and contains the DSCP.  The 6 most significant bits are
+ *                     used for the DSCP.  This setting has precedence over any
+ *                     IPv4- or IPv6- layer setting.
+ */
+static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
+					    char __user *optval, int __user *optlen)
+{
+	struct sctp_paddrparams  params;
+	struct sctp_transport   *trans = NULL;
+	struct sctp_association *asoc = NULL;
+	struct sctp_sock        *sp = sctp_sk(sk);
+
+	if (len >= sizeof(params))
+		len = sizeof(params);
+	else if (len >= ALIGN(offsetof(struct sctp_paddrparams,
+				       spp_ipv6_flowlabel), 4))
+		len = ALIGN(offsetof(struct sctp_paddrparams,
+				     spp_ipv6_flowlabel), 4);
+	else
+		return -EINVAL;
+
+	if (copy_from_user(&params, optval, len))
+		return -EFAULT;
+
+	/* If an address other than INADDR_ANY is specified, and
+	 * no transport is found, then the request is invalid.
+	 */
+	if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
+		trans = sctp_addr_id2transport(sk, &params.spp_address,
+					       params.spp_assoc_id);
+		if (!trans) {
+			pr_debug("%s: failed no transport\n", __func__);
+			return -EINVAL;
+		}
+	}
+
+	/* Get association, if assoc_id != 0 and the socket is a one
+	 * to many style socket, and an association was not found, then
+	 * the id was invalid.
+	 */
+	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
+	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
+		pr_debug("%s: failed no association\n", __func__);
+		return -EINVAL;
+	}
+
+	if (trans) {
+		/* Fetch transport values. */
+		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
+		params.spp_pathmtu    = trans->pathmtu;
+		params.spp_pathmaxrxt = trans->pathmaxrxt;
+		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
+
+		/*draft-11 doesn't say what to return in spp_flags*/
+		params.spp_flags      = trans->param_flags;
+		if (trans->flowlabel & SCTP_FLOWLABEL_SET_MASK) {
+			params.spp_ipv6_flowlabel = trans->flowlabel &
+						    SCTP_FLOWLABEL_VAL_MASK;
+			params.spp_flags |= SPP_IPV6_FLOWLABEL;
+		}
+		if (trans->dscp & SCTP_DSCP_SET_MASK) {
+			params.spp_dscp	= trans->dscp & SCTP_DSCP_VAL_MASK;
+			params.spp_flags |= SPP_DSCP;
+		}
+	} else if (asoc) {
+		/* Fetch association values. */
+		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
+		params.spp_pathmtu    = asoc->pathmtu;
+		params.spp_pathmaxrxt = asoc->pathmaxrxt;
+		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
+
+		/*draft-11 doesn't say what to return in spp_flags*/
+		params.spp_flags      = asoc->param_flags;
+		if (asoc->flowlabel & SCTP_FLOWLABEL_SET_MASK) {
+			params.spp_ipv6_flowlabel = asoc->flowlabel &
+						    SCTP_FLOWLABEL_VAL_MASK;
+			params.spp_flags |= SPP_IPV6_FLOWLABEL;
+		}
+		if (asoc->dscp & SCTP_DSCP_SET_MASK) {
+			params.spp_dscp	= asoc->dscp & SCTP_DSCP_VAL_MASK;
+			params.spp_flags |= SPP_DSCP;
+		}
+	} else {
+		/* Fetch socket values. */
+		params.spp_hbinterval = sp->hbinterval;
+		params.spp_pathmtu    = sp->pathmtu;
+		params.spp_sackdelay  = sp->sackdelay;
+		params.spp_pathmaxrxt = sp->pathmaxrxt;
+
+		/*draft-11 doesn't say what to return in spp_flags*/
+		params.spp_flags      = sp->param_flags;
+		if (sp->flowlabel & SCTP_FLOWLABEL_SET_MASK) {
+			params.spp_ipv6_flowlabel = sp->flowlabel &
+						    SCTP_FLOWLABEL_VAL_MASK;
+			params.spp_flags |= SPP_IPV6_FLOWLABEL;
+		}
+		if (sp->dscp & SCTP_DSCP_SET_MASK) {
+			params.spp_dscp	= sp->dscp & SCTP_DSCP_VAL_MASK;
+			params.spp_flags |= SPP_DSCP;
+		}
+	}
+
+	if (copy_to_user(optval, &params, len))
+		return -EFAULT;
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
+ *
+ * This option will effect the way delayed acks are performed.  This
+ * option allows you to get or set the delayed ack time, in
+ * milliseconds.  It also allows changing the delayed ack frequency.
+ * Changing the frequency to 1 disables the delayed sack algorithm.  If
+ * the assoc_id is 0, then this sets or gets the endpoints default
+ * values.  If the assoc_id field is non-zero, then the set or get
+ * effects the specified association for the one to many model (the
+ * assoc_id field is ignored by the one to one model).  Note that if
+ * sack_delay or sack_freq are 0 when setting this option, then the
+ * current values will remain unchanged.
+ *
+ * struct sctp_sack_info {
+ *     sctp_assoc_t            sack_assoc_id;
+ *     uint32_t                sack_delay;
+ *     uint32_t                sack_freq;
+ * };
+ *
+ * sack_assoc_id -  This parameter, indicates which association the user
+ *    is performing an action upon.  Note that if this field's value is
+ *    zero then the endpoints default value is changed (effecting future
+ *    associations only).
+ *
+ * sack_delay -  This parameter contains the number of milliseconds that
+ *    the user is requesting the delayed ACK timer be set to.  Note that
+ *    this value is defined in the standard to be between 200 and 500
+ *    milliseconds.
+ *
+ * sack_freq -  This parameter contains the number of packets that must
+ *    be received before a sack is sent without waiting for the delay
+ *    timer to expire.  The default value for this is 2, setting this
+ *    value to 1 will disable the delayed sack algorithm.
+ */
+static int sctp_getsockopt_delayed_ack(struct sock *sk, int len,
+					    char __user *optval,
+					    int __user *optlen)
+{
+	struct sctp_sack_info    params;
+	struct sctp_association *asoc = NULL;
+	struct sctp_sock        *sp = sctp_sk(sk);
+
+	if (len >= sizeof(struct sctp_sack_info)) {
+		len = sizeof(struct sctp_sack_info);
+
+		if (copy_from_user(&params, optval, len))
+			return -EFAULT;
+	} else if (len == sizeof(struct sctp_assoc_value)) {
+		pr_warn_ratelimited(DEPRECATED
+				    "%s (pid %d) "
+				    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
+				    "Use struct sctp_sack_info instead\n",
+				    current->comm, task_pid_nr(current));
+		if (copy_from_user(&params, optval, len))
+			return -EFAULT;
+	} else
+		return -EINVAL;
+
+	/* Get association, if sack_assoc_id != 0 and the socket is a one
+	 * to many style socket, and an association was not found, then
+	 * the id was invalid.
+	 */
+	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
+	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	if (asoc) {
+		/* Fetch association values. */
+		if (asoc->param_flags & SPP_SACKDELAY_ENABLE) {
+			params.sack_delay = jiffies_to_msecs(
+				asoc->sackdelay);
+			params.sack_freq = asoc->sackfreq;
+
+		} else {
+			params.sack_delay = 0;
+			params.sack_freq = 1;
+		}
+	} else {
+		/* Fetch socket values. */
+		if (sp->param_flags & SPP_SACKDELAY_ENABLE) {
+			params.sack_delay  = sp->sackdelay;
+			params.sack_freq = sp->sackfreq;
+		} else {
+			params.sack_delay  = 0;
+			params.sack_freq = 1;
+		}
+	}
+
+	if (copy_to_user(optval, &params, len))
+		return -EFAULT;
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+
+	return 0;
+}
+
+/* 7.1.3 Initialization Parameters (SCTP_INITMSG)
+ *
+ * Applications can specify protocol parameters for the default association
+ * initialization.  The option name argument to setsockopt() and getsockopt()
+ * is SCTP_INITMSG.
+ *
+ * Setting initialization parameters is effective only on an unconnected
+ * socket (for UDP-style sockets only future associations are effected
+ * by the change).  With TCP-style sockets, this option is inherited by
+ * sockets derived from a listener socket.
+ */
+static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
+{
+	if (len < sizeof(struct sctp_initmsg))
+		return -EINVAL;
+	len = sizeof(struct sctp_initmsg);
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
+		return -EFAULT;
+	return 0;
+}
+
+
+static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
+				      char __user *optval, int __user *optlen)
+{
+	struct sctp_association *asoc;
+	int cnt = 0;
+	struct sctp_getaddrs getaddrs;
+	struct sctp_transport *from;
+	void __user *to;
+	union sctp_addr temp;
+	struct sctp_sock *sp = sctp_sk(sk);
+	int addrlen;
+	size_t space_left;
+	int bytes_copied;
+
+	if (len < sizeof(struct sctp_getaddrs))
+		return -EINVAL;
+
+	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
+		return -EFAULT;
+
+	/* For UDP-style sockets, id specifies the association to query.  */
+	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	to = optval + offsetof(struct sctp_getaddrs, addrs);
+	space_left = len - offsetof(struct sctp_getaddrs, addrs);
+
+	list_for_each_entry(from, &asoc->peer.transport_addr_list,
+				transports) {
+		memcpy(&temp, &from->ipaddr, sizeof(temp));
+		addrlen = sctp_get_pf_specific(sk->sk_family)
+			      ->addr_to_user(sp, &temp);
+		if (space_left < addrlen)
+			return -ENOMEM;
+		if (copy_to_user(to, &temp, addrlen))
+			return -EFAULT;
+		to += addrlen;
+		cnt++;
+		space_left -= addrlen;
+	}
+
+	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
+		return -EFAULT;
+	bytes_copied = ((char __user *)to) - optval;
+	if (put_user(bytes_copied, optlen))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
+			    size_t space_left, int *bytes_copied)
+{
+	struct sctp_sockaddr_entry *addr;
+	union sctp_addr temp;
+	int cnt = 0;
+	int addrlen;
+	struct net *net = sock_net(sk);
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
+		if (!addr->valid)
+			continue;
+
+		if ((PF_INET == sk->sk_family) &&
+		    (AF_INET6 == addr->a.sa.sa_family))
+			continue;
+		if ((PF_INET6 == sk->sk_family) &&
+		    inet_v6_ipv6only(sk) &&
+		    (AF_INET == addr->a.sa.sa_family))
+			continue;
+		memcpy(&temp, &addr->a, sizeof(temp));
+		if (!temp.v4.sin_port)
+			temp.v4.sin_port = htons(port);
+
+		addrlen = sctp_get_pf_specific(sk->sk_family)
+			      ->addr_to_user(sctp_sk(sk), &temp);
+
+		if (space_left < addrlen) {
+			cnt =  -ENOMEM;
+			break;
+		}
+		memcpy(to, &temp, addrlen);
+
+		to += addrlen;
+		cnt++;
+		space_left -= addrlen;
+		*bytes_copied += addrlen;
+	}
+	rcu_read_unlock();
+
+	return cnt;
+}
+
+
+static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
+				       char __user *optval, int __user *optlen)
+{
+	struct sctp_bind_addr *bp;
+	struct sctp_association *asoc;
+	int cnt = 0;
+	struct sctp_getaddrs getaddrs;
+	struct sctp_sockaddr_entry *addr;
+	void __user *to;
+	union sctp_addr temp;
+	struct sctp_sock *sp = sctp_sk(sk);
+	int addrlen;
+	int err = 0;
+	size_t space_left;
+	int bytes_copied = 0;
+	void *addrs;
+	void *buf;
+
+	if (len < sizeof(struct sctp_getaddrs))
+		return -EINVAL;
+
+	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
+		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 == 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 = optval + offsetof(struct sctp_getaddrs, addrs);
+	space_left = len - offsetof(struct sctp_getaddrs, addrs);
+
+	addrs = kmalloc(space_left, GFP_USER | __GFP_NOWARN);
+	if (!addrs)
+		return -ENOMEM;
+
+	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
+	 * addresses from the global local address list.
+	 */
+	if (sctp_list_single_entry(&bp->address_list)) {
+		addr = list_entry(bp->address_list.next,
+				  struct sctp_sockaddr_entry, list);
+		if (sctp_is_any(sk, &addr->a)) {
+			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
+						space_left, &bytes_copied);
+			if (cnt < 0) {
+				err = cnt;
+				goto out;
+			}
+			goto copy_getaddrs;
+		}
+	}
+
+	buf = addrs;
+	/* Protection on the bound address list is not needed since
+	 * in the socket option context we hold a socket lock and
+	 * thus the bound address list can't change.
+	 */
+	list_for_each_entry(addr, &bp->address_list, list) {
+		memcpy(&temp, &addr->a, sizeof(temp));
+		addrlen = sctp_get_pf_specific(sk->sk_family)
+			      ->addr_to_user(sp, &temp);
+		if (space_left < addrlen) {
+			err =  -ENOMEM; /*fixme: right error?*/
+			goto out;
+		}
+		memcpy(buf, &temp, addrlen);
+		buf += addrlen;
+		bytes_copied += addrlen;
+		cnt++;
+		space_left -= addrlen;
+	}
+
+copy_getaddrs:
+	if (copy_to_user(to, addrs, bytes_copied)) {
+		err = -EFAULT;
+		goto out;
+	}
+	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
+		err = -EFAULT;
+		goto out;
+	}
+	/* XXX: We should have accounted for sizeof(struct sctp_getaddrs) too,
+	 * but we can't change it anymore.
+	 */
+	if (put_user(bytes_copied, optlen))
+		err = -EFAULT;
+out:
+	kfree(addrs);
+	return err;
+}
+
+/* 7.1.10 Set Primary Address (SCTP_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_primary_addr(struct sock *sk, int len,
+					char __user *optval, int __user *optlen)
+{
+	struct sctp_prim prim;
+	struct sctp_association *asoc;
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	if (len < sizeof(struct sctp_prim))
+		return -EINVAL;
+
+	len = sizeof(struct sctp_prim);
+
+	if (copy_from_user(&prim, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	if (!asoc->peer.primary_path)
+		return -ENOTCONN;
+
+	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
+		asoc->peer.primary_path->af_specific->sockaddr_len);
+
+	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sp,
+			(union sctp_addr *)&prim.ssp_addr);
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &prim, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
+ *
+ * Requests that the local endpoint set the specified Adaptation Layer
+ * Indication parameter for all future INIT and INIT-ACK exchanges.
+ */
+static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
+				  char __user *optval, int __user *optlen)
+{
+	struct sctp_setadaptation adaptation;
+
+	if (len < sizeof(struct sctp_setadaptation))
+		return -EINVAL;
+
+	len = sizeof(struct sctp_setadaptation);
+
+	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &adaptation, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ *
+ * 7.1.14 Set default send parameters (SCTP_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 __user *optval,
+					int __user *optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_association *asoc;
+	struct sctp_sndrcvinfo info;
+
+	if (len < sizeof(info))
+		return -EINVAL;
+
+	len = sizeof(info);
+
+	if (copy_from_user(&info, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
+	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+	if (asoc) {
+		info.sinfo_stream = asoc->default_stream;
+		info.sinfo_flags = asoc->default_flags;
+		info.sinfo_ppid = asoc->default_ppid;
+		info.sinfo_context = asoc->default_context;
+		info.sinfo_timetolive = asoc->default_timetolive;
+	} else {
+		info.sinfo_stream = sp->default_stream;
+		info.sinfo_flags = sp->default_flags;
+		info.sinfo_ppid = sp->default_ppid;
+		info.sinfo_context = sp->default_context;
+		info.sinfo_timetolive = sp->default_timetolive;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &info, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/* RFC6458, Section 8.1.31. Set/get Default Send Parameters
+ * (SCTP_DEFAULT_SNDINFO)
+ */
+static int sctp_getsockopt_default_sndinfo(struct sock *sk, int len,
+					   char __user *optval,
+					   int __user *optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_association *asoc;
+	struct sctp_sndinfo info;
+
+	if (len < sizeof(info))
+		return -EINVAL;
+
+	len = sizeof(info);
+
+	if (copy_from_user(&info, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
+	if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+	if (asoc) {
+		info.snd_sid = asoc->default_stream;
+		info.snd_flags = asoc->default_flags;
+		info.snd_ppid = asoc->default_ppid;
+		info.snd_context = asoc->default_context;
+	} else {
+		info.snd_sid = sp->default_stream;
+		info.snd_flags = sp->default_flags;
+		info.snd_ppid = sp->default_ppid;
+		info.snd_context = sp->default_context;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &info, len))
+		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 __user *optval, int __user *optlen)
+{
+	int val;
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+	val = (sctp_sk(sk)->nodelay == 1);
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+	return 0;
+}
+
+/*
+ *
+ * 7.1.1 SCTP_RTOINFO
+ *
+ * The protocol parameters used to initialize and bound retransmission
+ * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
+ * and modify these parameters.
+ * All parameters are time values, in milliseconds.  A value of 0, when
+ * modifying the parameters, indicates that the current value should not
+ * be changed.
+ *
+ */
+static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
+				char __user *optval,
+				int __user *optlen) {
+	struct sctp_rtoinfo rtoinfo;
+	struct sctp_association *asoc;
+
+	if (len < sizeof (struct sctp_rtoinfo))
+		return -EINVAL;
+
+	len = sizeof(struct sctp_rtoinfo);
+
+	if (copy_from_user(&rtoinfo, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
+
+	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	/* Values corresponding to the specific association. */
+	if (asoc) {
+		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
+		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
+		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
+	} else {
+		/* Values corresponding to the endpoint. */
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
+		rtoinfo.srto_max = sp->rtoinfo.srto_max;
+		rtoinfo.srto_min = sp->rtoinfo.srto_min;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+
+	if (copy_to_user(optval, &rtoinfo, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ *
+ * 7.1.2 SCTP_ASSOCINFO
+ *
+ * This option is used to tune the maximum retransmission attempts
+ * of the association.
+ * Returns an error if the new association retransmission value is
+ * greater than the sum of the retransmission value  of the peer.
+ * See [SCTP] for more information.
+ *
+ */
+static int sctp_getsockopt_associnfo(struct sock *sk, int len,
+				     char __user *optval,
+				     int __user *optlen)
+{
+
+	struct sctp_assocparams assocparams;
+	struct sctp_association *asoc;
+	struct list_head *pos;
+	int cnt = 0;
+
+	if (len < sizeof (struct sctp_assocparams))
+		return -EINVAL;
+
+	len = sizeof(struct sctp_assocparams);
+
+	if (copy_from_user(&assocparams, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
+
+	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	/* Values correspoinding to the specific association */
+	if (asoc) {
+		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
+		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
+		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
+		assocparams.sasoc_cookie_life = ktime_to_ms(asoc->cookie_life);
+
+		list_for_each(pos, &asoc->peer.transport_addr_list) {
+			cnt++;
+		}
+
+		assocparams.sasoc_number_peer_destinations = cnt;
+	} else {
+		/* Values corresponding to the endpoint */
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
+		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
+		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
+		assocparams.sasoc_cookie_life =
+					sp->assocparams.sasoc_cookie_life;
+		assocparams.sasoc_number_peer_destinations =
+					sp->assocparams.
+					sasoc_number_peer_destinations;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+
+	if (copy_to_user(optval, &assocparams, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
+ *
+ * This socket option is a boolean flag which turns on or off mapped V4
+ * addresses.  If this option is turned on and the socket is type
+ * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
+ * If this option is turned off, then no mapping will be done of V4
+ * addresses and a user will receive both PF_INET6 and PF_INET type
+ * addresses on the socket.
+ */
+static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
+				    char __user *optval, int __user *optlen)
+{
+	int val;
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+	val = sp->v4mapped;
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
+ * (chapter and verse is quoted at sctp_setsockopt_context())
+ */
+static int sctp_getsockopt_context(struct sock *sk, int len,
+				   char __user *optval, int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_sock *sp;
+	struct sctp_association *asoc;
+
+	if (len < sizeof(struct sctp_assoc_value))
+		return -EINVAL;
+
+	len = sizeof(struct sctp_assoc_value);
+
+	if (copy_from_user(&params, optval, len))
+		return -EFAULT;
+
+	sp = sctp_sk(sk);
+
+	if (params.assoc_id != 0) {
+		asoc = sctp_id2assoc(sk, params.assoc_id);
+		if (!asoc)
+			return -EINVAL;
+		params.assoc_value = asoc->default_rcv_context;
+	} else {
+		params.assoc_value = sp->default_rcv_context;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &params, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
+ * This option will get or set the maximum size to put in any outgoing
+ * SCTP DATA chunk.  If a message is larger than this size it will be
+ * fragmented by SCTP into the specified size.  Note that the underlying
+ * SCTP implementation may fragment into smaller sized chunks when the
+ * PMTU of the underlying association is smaller than the value set by
+ * the user.  The default value for this option is '0' which indicates
+ * the user is NOT limiting fragmentation and only the PMTU will effect
+ * SCTP's choice of DATA chunk size.  Note also that values set larger
+ * than the maximum size of an IP datagram will effectively let SCTP
+ * control fragmentation (i.e. the same as setting this option to 0).
+ *
+ * The following structure is used to access and modify this parameter:
+ *
+ * struct sctp_assoc_value {
+ *   sctp_assoc_t assoc_id;
+ *   uint32_t assoc_value;
+ * };
+ *
+ * assoc_id:  This parameter is ignored for one-to-one style sockets.
+ *    For one-to-many style sockets this parameter indicates which
+ *    association the user is performing an action upon.  Note that if
+ *    this field's value is zero then the endpoints default value is
+ *    changed (effecting future associations only).
+ * assoc_value:  This parameter specifies the maximum size in bytes.
+ */
+static int sctp_getsockopt_maxseg(struct sock *sk, int len,
+				  char __user *optval, int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+
+	if (len == sizeof(int)) {
+		pr_warn_ratelimited(DEPRECATED
+				    "%s (pid %d) "
+				    "Use of int in maxseg socket option.\n"
+				    "Use struct sctp_assoc_value instead\n",
+				    current->comm, task_pid_nr(current));
+		params.assoc_id = 0;
+	} else if (len >= sizeof(struct sctp_assoc_value)) {
+		len = sizeof(struct sctp_assoc_value);
+		if (copy_from_user(&params, optval, len))
+			return -EFAULT;
+	} else
+		return -EINVAL;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	if (asoc)
+		params.assoc_value = asoc->frag_point;
+	else
+		params.assoc_value = sctp_sk(sk)->user_frag;
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (len == sizeof(int)) {
+		if (copy_to_user(optval, &params.assoc_value, len))
+			return -EFAULT;
+	} else {
+		if (copy_to_user(optval, &params, len))
+			return -EFAULT;
+	}
+
+	return 0;
+}
+
+/*
+ * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
+ * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
+ */
+static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
+					       char __user *optval, int __user *optlen)
+{
+	int val;
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+
+	val = sctp_sk(sk)->frag_interleave;
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 7.1.25.  Set or Get the sctp partial delivery point
+ * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
+ */
+static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
+						  char __user *optval,
+						  int __user *optlen)
+{
+	u32 val;
+
+	if (len < sizeof(u32))
+		return -EINVAL;
+
+	len = sizeof(u32);
+
+	val = sctp_sk(sk)->pd_point;
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
+ * (chapter and verse is quoted at sctp_setsockopt_maxburst())
+ */
+static int sctp_getsockopt_maxburst(struct sock *sk, int len,
+				    char __user *optval,
+				    int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_sock *sp;
+	struct sctp_association *asoc;
+
+	if (len == sizeof(int)) {
+		pr_warn_ratelimited(DEPRECATED
+				    "%s (pid %d) "
+				    "Use of int in max_burst socket option.\n"
+				    "Use struct sctp_assoc_value instead\n",
+				    current->comm, task_pid_nr(current));
+		params.assoc_id = 0;
+	} else if (len >= sizeof(struct sctp_assoc_value)) {
+		len = sizeof(struct sctp_assoc_value);
+		if (copy_from_user(&params, optval, len))
+			return -EFAULT;
+	} else
+		return -EINVAL;
+
+	sp = sctp_sk(sk);
+
+	if (params.assoc_id != 0) {
+		asoc = sctp_id2assoc(sk, params.assoc_id);
+		if (!asoc)
+			return -EINVAL;
+		params.assoc_value = asoc->max_burst;
+	} else
+		params.assoc_value = sp->max_burst;
+
+	if (len == sizeof(int)) {
+		if (copy_to_user(optval, &params.assoc_value, len))
+			return -EFAULT;
+	} else {
+		if (copy_to_user(optval, &params, len))
+			return -EFAULT;
+	}
+
+	return 0;
+
+}
+
+static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
+				    char __user *optval, int __user *optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_hmacalgo  __user *p = (void __user *)optval;
+	struct sctp_hmac_algo_param *hmacs;
+	__u16 data_len = 0;
+	u32 num_idents;
+	int i;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	hmacs = ep->auth_hmacs_list;
+	data_len = ntohs(hmacs->param_hdr.length) -
+		   sizeof(struct sctp_paramhdr);
+
+	if (len < sizeof(struct sctp_hmacalgo) + data_len)
+		return -EINVAL;
+
+	len = sizeof(struct sctp_hmacalgo) + data_len;
+	num_idents = data_len / sizeof(u16);
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (put_user(num_idents, &p->shmac_num_idents))
+		return -EFAULT;
+	for (i = 0; i < num_idents; i++) {
+		__u16 hmacid = ntohs(hmacs->hmac_ids[i]);
+
+		if (copy_to_user(&p->shmac_idents[i], &hmacid, sizeof(__u16)))
+			return -EFAULT;
+	}
+	return 0;
+}
+
+static int sctp_getsockopt_active_key(struct sock *sk, int len,
+				    char __user *optval, int __user *optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_authkeyid val;
+	struct sctp_association *asoc;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (len < sizeof(struct sctp_authkeyid))
+		return -EINVAL;
+
+	len = sizeof(struct sctp_authkeyid);
+	if (copy_from_user(&val, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
+	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	if (asoc)
+		val.scact_keynumber = asoc->active_key_id;
+	else
+		val.scact_keynumber = ep->active_key_id;
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
+				    char __user *optval, int __user *optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_authchunks __user *p = (void __user *)optval;
+	struct sctp_authchunks val;
+	struct sctp_association *asoc;
+	struct sctp_chunks_param *ch;
+	u32    num_chunks = 0;
+	char __user *to;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (len < sizeof(struct sctp_authchunks))
+		return -EINVAL;
+
+	if (copy_from_user(&val, optval, sizeof(val)))
+		return -EFAULT;
+
+	to = p->gauth_chunks;
+	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	ch = asoc->peer.peer_chunks;
+	if (!ch)
+		goto num;
+
+	/* See if the user provided enough room for all the data */
+	num_chunks = ntohs(ch->param_hdr.length) - sizeof(struct sctp_paramhdr);
+	if (len < num_chunks)
+		return -EINVAL;
+
+	if (copy_to_user(to, ch->chunks, num_chunks))
+		return -EFAULT;
+num:
+	len = sizeof(struct sctp_authchunks) + num_chunks;
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (put_user(num_chunks, &p->gauth_number_of_chunks))
+		return -EFAULT;
+	return 0;
+}
+
+static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
+				    char __user *optval, int __user *optlen)
+{
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	struct sctp_authchunks __user *p = (void __user *)optval;
+	struct sctp_authchunks val;
+	struct sctp_association *asoc;
+	struct sctp_chunks_param *ch;
+	u32    num_chunks = 0;
+	char __user *to;
+
+	if (!ep->auth_enable)
+		return -EACCES;
+
+	if (len < sizeof(struct sctp_authchunks))
+		return -EINVAL;
+
+	if (copy_from_user(&val, optval, sizeof(val)))
+		return -EFAULT;
+
+	to = p->gauth_chunks;
+	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
+	if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	if (asoc)
+		ch = (struct sctp_chunks_param *)asoc->c.auth_chunks;
+	else
+		ch = ep->auth_chunk_list;
+
+	if (!ch)
+		goto num;
+
+	num_chunks = ntohs(ch->param_hdr.length) - sizeof(struct sctp_paramhdr);
+	if (len < sizeof(struct sctp_authchunks) + num_chunks)
+		return -EINVAL;
+
+	if (copy_to_user(to, ch->chunks, num_chunks))
+		return -EFAULT;
+num:
+	len = sizeof(struct sctp_authchunks) + num_chunks;
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (put_user(num_chunks, &p->gauth_number_of_chunks))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 8.2.5.  Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)
+ * This option gets the current number of associations that are attached
+ * to a one-to-many style socket.  The option value is an uint32_t.
+ */
+static int sctp_getsockopt_assoc_number(struct sock *sk, int len,
+				    char __user *optval, int __user *optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_association *asoc;
+	u32 val = 0;
+
+	if (sctp_style(sk, TCP))
+		return -EOPNOTSUPP;
+
+	if (len < sizeof(u32))
+		return -EINVAL;
+
+	len = sizeof(u32);
+
+	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
+		val++;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * 8.1.23 SCTP_AUTO_ASCONF
+ * See the corresponding setsockopt entry as description
+ */
+static int sctp_getsockopt_auto_asconf(struct sock *sk, int len,
+				   char __user *optval, int __user *optlen)
+{
+	int val = 0;
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+	if (sctp_sk(sk)->do_auto_asconf && sctp_is_ep_boundall(sk))
+		val = 1;
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+	return 0;
+}
+
+/*
+ * 8.2.6. Get the Current Identifiers of Associations
+ *        (SCTP_GET_ASSOC_ID_LIST)
+ *
+ * This option gets the current list of SCTP association identifiers of
+ * the SCTP associations handled by a one-to-many style socket.
+ */
+static int sctp_getsockopt_assoc_ids(struct sock *sk, int len,
+				    char __user *optval, int __user *optlen)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_association *asoc;
+	struct sctp_assoc_ids *ids;
+	u32 num = 0;
+
+	if (sctp_style(sk, TCP))
+		return -EOPNOTSUPP;
+
+	if (len < sizeof(struct sctp_assoc_ids))
+		return -EINVAL;
+
+	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
+		num++;
+	}
+
+	if (len < sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num)
+		return -EINVAL;
+
+	len = sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num;
+
+	ids = kmalloc(len, GFP_USER | __GFP_NOWARN);
+	if (unlikely(!ids))
+		return -ENOMEM;
+
+	ids->gaids_number_of_ids = num;
+	num = 0;
+	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
+		ids->gaids_assoc_id[num++] = asoc->assoc_id;
+	}
+
+	if (put_user(len, optlen) || copy_to_user(optval, ids, len)) {
+		kfree(ids);
+		return -EFAULT;
+	}
+
+	kfree(ids);
+	return 0;
+}
+
+/*
+ * SCTP_PEER_ADDR_THLDS
+ *
+ * This option allows us to fetch the partially failed threshold for one or all
+ * transports in an association.  See Section 6.1 of:
+ * http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt
+ */
+static int sctp_getsockopt_paddr_thresholds(struct sock *sk,
+					    char __user *optval,
+					    int len,
+					    int __user *optlen)
+{
+	struct sctp_paddrthlds val;
+	struct sctp_transport *trans;
+	struct sctp_association *asoc;
+
+	if (len < sizeof(struct sctp_paddrthlds))
+		return -EINVAL;
+	len = sizeof(struct sctp_paddrthlds);
+	if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval, len))
+		return -EFAULT;
+
+	if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
+		asoc = sctp_id2assoc(sk, val.spt_assoc_id);
+		if (!asoc)
+			return -ENOENT;
+
+		val.spt_pathpfthld = asoc->pf_retrans;
+		val.spt_pathmaxrxt = asoc->pathmaxrxt;
+	} else {
+		trans = sctp_addr_id2transport(sk, &val.spt_address,
+					       val.spt_assoc_id);
+		if (!trans)
+			return -ENOENT;
+
+		val.spt_pathmaxrxt = trans->pathmaxrxt;
+		val.spt_pathpfthld = trans->pf_retrans;
+	}
+
+	if (put_user(len, optlen) || copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * SCTP_GET_ASSOC_STATS
+ *
+ * This option retrieves local per endpoint statistics. It is modeled
+ * after OpenSolaris' implementation
+ */
+static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
+				       char __user *optval,
+				       int __user *optlen)
+{
+	struct sctp_assoc_stats sas;
+	struct sctp_association *asoc = NULL;
+
+	/* User must provide at least the assoc id */
+	if (len < sizeof(sctp_assoc_t))
+		return -EINVAL;
+
+	/* Allow the struct to grow and fill in as much as possible */
+	len = min_t(size_t, len, sizeof(sas));
+
+	if (copy_from_user(&sas, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, sas.sas_assoc_id);
+	if (!asoc)
+		return -EINVAL;
+
+	sas.sas_rtxchunks = asoc->stats.rtxchunks;
+	sas.sas_gapcnt = asoc->stats.gapcnt;
+	sas.sas_outofseqtsns = asoc->stats.outofseqtsns;
+	sas.sas_osacks = asoc->stats.osacks;
+	sas.sas_isacks = asoc->stats.isacks;
+	sas.sas_octrlchunks = asoc->stats.octrlchunks;
+	sas.sas_ictrlchunks = asoc->stats.ictrlchunks;
+	sas.sas_oodchunks = asoc->stats.oodchunks;
+	sas.sas_iodchunks = asoc->stats.iodchunks;
+	sas.sas_ouodchunks = asoc->stats.ouodchunks;
+	sas.sas_iuodchunks = asoc->stats.iuodchunks;
+	sas.sas_idupchunks = asoc->stats.idupchunks;
+	sas.sas_opackets = asoc->stats.opackets;
+	sas.sas_ipackets = asoc->stats.ipackets;
+
+	/* New high max rto observed, will return 0 if not a single
+	 * RTO update took place. obs_rto_ipaddr will be bogus
+	 * in such a case
+	 */
+	sas.sas_maxrto = asoc->stats.max_obs_rto;
+	memcpy(&sas.sas_obs_rto_ipaddr, &asoc->stats.obs_rto_ipaddr,
+		sizeof(struct sockaddr_storage));
+
+	/* Mark beginning of a new observation period */
+	asoc->stats.max_obs_rto = asoc->rto_min;
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+
+	pr_debug("%s: len:%d, assoc_id:%d\n", __func__, len, sas.sas_assoc_id);
+
+	if (copy_to_user(optval, &sas, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_getsockopt_recvrcvinfo(struct sock *sk,	int len,
+				       char __user *optval,
+				       int __user *optlen)
+{
+	int val = 0;
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+	if (sctp_sk(sk)->recvrcvinfo)
+		val = 1;
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_getsockopt_recvnxtinfo(struct sock *sk,	int len,
+				       char __user *optval,
+				       int __user *optlen)
+{
+	int val = 0;
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+	if (sctp_sk(sk)->recvnxtinfo)
+		val = 1;
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_getsockopt_pr_supported(struct sock *sk, int len,
+					char __user *optval,
+					int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(params)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (asoc) {
+		params.assoc_value = asoc->prsctp_enable;
+	} else if (!params.assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		params.assoc_value = sp->ep->prsctp_enable;
+	} else {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	if (put_user(len, optlen))
+		goto out;
+
+	if (copy_to_user(optval, &params, len))
+		goto out;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_default_prinfo(struct sock *sk, int len,
+					  char __user *optval,
+					  int __user *optlen)
+{
+	struct sctp_default_prinfo info;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(info)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(info);
+	if (copy_from_user(&info, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, info.pr_assoc_id);
+	if (asoc) {
+		info.pr_policy = SCTP_PR_POLICY(asoc->default_flags);
+		info.pr_value = asoc->default_timetolive;
+	} else if (!info.pr_assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		info.pr_policy = SCTP_PR_POLICY(sp->default_flags);
+		info.pr_value = sp->default_timetolive;
+	} else {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	if (put_user(len, optlen))
+		goto out;
+
+	if (copy_to_user(optval, &info, len))
+		goto out;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_pr_assocstatus(struct sock *sk, int len,
+					  char __user *optval,
+					  int __user *optlen)
+{
+	struct sctp_prstatus params;
+	struct sctp_association *asoc;
+	int policy;
+	int retval = -EINVAL;
+
+	if (len < sizeof(params))
+		goto out;
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	policy = params.sprstat_policy;
+	if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL)) ||
+	    ((policy & SCTP_PR_SCTP_ALL) && (policy & SCTP_PR_SCTP_MASK)))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.sprstat_assoc_id);
+	if (!asoc)
+		goto out;
+
+	if (policy == SCTP_PR_SCTP_ALL) {
+		params.sprstat_abandoned_unsent = 0;
+		params.sprstat_abandoned_sent = 0;
+		for (policy = 0; policy <= SCTP_PR_INDEX(MAX); policy++) {
+			params.sprstat_abandoned_unsent +=
+				asoc->abandoned_unsent[policy];
+			params.sprstat_abandoned_sent +=
+				asoc->abandoned_sent[policy];
+		}
+	} else {
+		params.sprstat_abandoned_unsent =
+			asoc->abandoned_unsent[__SCTP_PR_INDEX(policy)];
+		params.sprstat_abandoned_sent =
+			asoc->abandoned_sent[__SCTP_PR_INDEX(policy)];
+	}
+
+	if (put_user(len, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (copy_to_user(optval, &params, len)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_pr_streamstatus(struct sock *sk, int len,
+					   char __user *optval,
+					   int __user *optlen)
+{
+	struct sctp_stream_out_ext *streamoute;
+	struct sctp_association *asoc;
+	struct sctp_prstatus params;
+	int retval = -EINVAL;
+	int policy;
+
+	if (len < sizeof(params))
+		goto out;
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	policy = params.sprstat_policy;
+	if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL)) ||
+	    ((policy & SCTP_PR_SCTP_ALL) && (policy & SCTP_PR_SCTP_MASK)))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.sprstat_assoc_id);
+	if (!asoc || params.sprstat_sid >= asoc->stream.outcnt)
+		goto out;
+
+	streamoute = SCTP_SO(&asoc->stream, params.sprstat_sid)->ext;
+	if (!streamoute) {
+		/* Not allocated yet, means all stats are 0 */
+		params.sprstat_abandoned_unsent = 0;
+		params.sprstat_abandoned_sent = 0;
+		retval = 0;
+		goto out;
+	}
+
+	if (policy == SCTP_PR_SCTP_ALL) {
+		params.sprstat_abandoned_unsent = 0;
+		params.sprstat_abandoned_sent = 0;
+		for (policy = 0; policy <= SCTP_PR_INDEX(MAX); policy++) {
+			params.sprstat_abandoned_unsent +=
+				streamoute->abandoned_unsent[policy];
+			params.sprstat_abandoned_sent +=
+				streamoute->abandoned_sent[policy];
+		}
+	} else {
+		params.sprstat_abandoned_unsent =
+			streamoute->abandoned_unsent[__SCTP_PR_INDEX(policy)];
+		params.sprstat_abandoned_sent =
+			streamoute->abandoned_sent[__SCTP_PR_INDEX(policy)];
+	}
+
+	if (put_user(len, optlen) || copy_to_user(optval, &params, len)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_reconfig_supported(struct sock *sk, int len,
+					      char __user *optval,
+					      int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(params)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (asoc) {
+		params.assoc_value = asoc->reconf_enable;
+	} else if (!params.assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		params.assoc_value = sp->ep->reconf_enable;
+	} else {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	if (put_user(len, optlen))
+		goto out;
+
+	if (copy_to_user(optval, &params, len))
+		goto out;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_enable_strreset(struct sock *sk, int len,
+					   char __user *optval,
+					   int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(params)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (asoc) {
+		params.assoc_value = asoc->strreset_enable;
+	} else if (!params.assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		params.assoc_value = sp->ep->strreset_enable;
+	} else {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	if (put_user(len, optlen))
+		goto out;
+
+	if (copy_to_user(optval, &params, len))
+		goto out;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_scheduler(struct sock *sk, int len,
+				     char __user *optval,
+				     int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(params)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (!asoc) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	params.assoc_value = sctp_sched_get_sched(asoc);
+
+	if (put_user(len, optlen))
+		goto out;
+
+	if (copy_to_user(optval, &params, len))
+		goto out;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_scheduler_value(struct sock *sk, int len,
+					   char __user *optval,
+					   int __user *optlen)
+{
+	struct sctp_stream_value params;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(params)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (!asoc) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	retval = sctp_sched_get_value(asoc, params.stream_id,
+				      &params.stream_value);
+	if (retval)
+		goto out;
+
+	if (put_user(len, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (copy_to_user(optval, &params, len)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_interleaving_supported(struct sock *sk, int len,
+						  char __user *optval,
+						  int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(params)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (asoc) {
+		params.assoc_value = asoc->intl_enable;
+	} else if (!params.assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		params.assoc_value = sp->strm_interleave;
+	} else {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	if (put_user(len, optlen))
+		goto out;
+
+	if (copy_to_user(optval, &params, len))
+		goto out;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
+static int sctp_getsockopt_reuse_port(struct sock *sk, int len,
+				      char __user *optval,
+				      int __user *optlen)
+{
+	int val;
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+	val = sctp_sk(sk)->reuse;
+	if (put_user(len, optlen))
+		return -EFAULT;
+
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int sctp_getsockopt(struct sock *sk, int level, int optname,
+			   char __user *optval, int __user *optlen)
+{
+	int retval = 0;
+	int len;
+
+	pr_debug("%s: sk:%p, optname:%d\n", __func__, 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 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;
+
+	if (len < 0)
+		return -EINVAL;
+
+	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_EVENTS:
+		retval = sctp_getsockopt_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_SOCKOPT_PEELOFF_FLAGS:
+		retval = sctp_getsockopt_peeloff_flags(sk, len, optval, optlen);
+		break;
+	case SCTP_PEER_ADDR_PARAMS:
+		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
+							  optlen);
+		break;
+	case SCTP_DELAYED_SACK:
+		retval = sctp_getsockopt_delayed_ack(sk, len, optval,
+							  optlen);
+		break;
+	case SCTP_INITMSG:
+		retval = sctp_getsockopt_initmsg(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_SOCKOPT_CONNECTX3:
+		retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
+		break;
+	case SCTP_DEFAULT_SEND_PARAM:
+		retval = sctp_getsockopt_default_send_param(sk, len,
+							    optval, optlen);
+		break;
+	case SCTP_DEFAULT_SNDINFO:
+		retval = sctp_getsockopt_default_sndinfo(sk, len,
+							 optval, optlen);
+		break;
+	case SCTP_PRIMARY_ADDR:
+		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
+		break;
+	case SCTP_NODELAY:
+		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
+		break;
+	case SCTP_RTOINFO:
+		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
+		break;
+	case SCTP_ASSOCINFO:
+		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
+		break;
+	case SCTP_I_WANT_MAPPED_V4_ADDR:
+		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
+		break;
+	case SCTP_MAXSEG:
+		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
+		break;
+	case SCTP_GET_PEER_ADDR_INFO:
+		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
+							optlen);
+		break;
+	case SCTP_ADAPTATION_LAYER:
+		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
+							optlen);
+		break;
+	case SCTP_CONTEXT:
+		retval = sctp_getsockopt_context(sk, len, optval, optlen);
+		break;
+	case SCTP_FRAGMENT_INTERLEAVE:
+		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
+							     optlen);
+		break;
+	case SCTP_PARTIAL_DELIVERY_POINT:
+		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
+								optlen);
+		break;
+	case SCTP_MAX_BURST:
+		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
+		break;
+	case SCTP_AUTH_KEY:
+	case SCTP_AUTH_CHUNK:
+	case SCTP_AUTH_DELETE_KEY:
+	case SCTP_AUTH_DEACTIVATE_KEY:
+		retval = -EOPNOTSUPP;
+		break;
+	case SCTP_HMAC_IDENT:
+		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
+		break;
+	case SCTP_AUTH_ACTIVE_KEY:
+		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
+		break;
+	case SCTP_PEER_AUTH_CHUNKS:
+		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
+							optlen);
+		break;
+	case SCTP_LOCAL_AUTH_CHUNKS:
+		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
+							optlen);
+		break;
+	case SCTP_GET_ASSOC_NUMBER:
+		retval = sctp_getsockopt_assoc_number(sk, len, optval, optlen);
+		break;
+	case SCTP_GET_ASSOC_ID_LIST:
+		retval = sctp_getsockopt_assoc_ids(sk, len, optval, optlen);
+		break;
+	case SCTP_AUTO_ASCONF:
+		retval = sctp_getsockopt_auto_asconf(sk, len, optval, optlen);
+		break;
+	case SCTP_PEER_ADDR_THLDS:
+		retval = sctp_getsockopt_paddr_thresholds(sk, optval, len, optlen);
+		break;
+	case SCTP_GET_ASSOC_STATS:
+		retval = sctp_getsockopt_assoc_stats(sk, len, optval, optlen);
+		break;
+	case SCTP_RECVRCVINFO:
+		retval = sctp_getsockopt_recvrcvinfo(sk, len, optval, optlen);
+		break;
+	case SCTP_RECVNXTINFO:
+		retval = sctp_getsockopt_recvnxtinfo(sk, len, optval, optlen);
+		break;
+	case SCTP_PR_SUPPORTED:
+		retval = sctp_getsockopt_pr_supported(sk, len, optval, optlen);
+		break;
+	case SCTP_DEFAULT_PRINFO:
+		retval = sctp_getsockopt_default_prinfo(sk, len, optval,
+							optlen);
+		break;
+	case SCTP_PR_ASSOC_STATUS:
+		retval = sctp_getsockopt_pr_assocstatus(sk, len, optval,
+							optlen);
+		break;
+	case SCTP_PR_STREAM_STATUS:
+		retval = sctp_getsockopt_pr_streamstatus(sk, len, optval,
+							 optlen);
+		break;
+	case SCTP_RECONFIG_SUPPORTED:
+		retval = sctp_getsockopt_reconfig_supported(sk, len, optval,
+							    optlen);
+		break;
+	case SCTP_ENABLE_STREAM_RESET:
+		retval = sctp_getsockopt_enable_strreset(sk, len, optval,
+							 optlen);
+		break;
+	case SCTP_STREAM_SCHEDULER:
+		retval = sctp_getsockopt_scheduler(sk, len, optval,
+						   optlen);
+		break;
+	case SCTP_STREAM_SCHEDULER_VALUE:
+		retval = sctp_getsockopt_scheduler_value(sk, len, optval,
+							 optlen);
+		break;
+	case SCTP_INTERLEAVING_SUPPORTED:
+		retval = sctp_getsockopt_interleaving_supported(sk, len, optval,
+								optlen);
+		break;
+	case SCTP_REUSE_PORT:
+		retval = sctp_getsockopt_reuse_port(sk, len, optval, optlen);
+		break;
+	default:
+		retval = -ENOPROTOOPT;
+		break;
+	}
+
+	release_sock(sk);
+	return retval;
+}
+
+static int sctp_hash(struct sock *sk)
+{
+	/* STUB */
+	return 0;
+}
+
+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). 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 struct sctp_bind_bucket *sctp_bucket_create(
+	struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);
+
+static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
+{
+	bool reuse = (sk->sk_reuse || sctp_sk(sk)->reuse);
+	struct sctp_bind_hashbucket *head; /* hash list */
+	struct sctp_bind_bucket *pp;
+	unsigned short snum;
+	int ret;
+
+	snum = ntohs(addr->v4.sin_port);
+
+	pr_debug("%s: begins, snum:%d\n", __func__, snum);
+
+	if (snum == 0) {
+		/* Search for an available port. */
+		int low, high, remaining, index;
+		unsigned int rover;
+		struct net *net = sock_net(sk);
+
+		inet_get_local_port_range(net, &low, &high);
+		remaining = (high - low) + 1;
+		rover = prandom_u32() % remaining + low;
+
+		do {
+			rover++;
+			if ((rover < low) || (rover > high))
+				rover = low;
+			if (inet_is_local_reserved_port(net, rover))
+				continue;
+			index = sctp_phashfn(sock_net(sk), rover);
+			head = &sctp_port_hashtable[index];
+			spin_lock_bh(&head->lock);
+			sctp_for_each_hentry(pp, &head->chain)
+				if ((pp->port == rover) &&
+				    net_eq(sock_net(sk), pp->net))
+					goto next;
+			break;
+		next:
+			spin_unlock_bh(&head->lock);
+			cond_resched();
+		} while (--remaining > 0);
+
+		/* Exhausted local port range during search? */
+		ret = 1;
+		if (remaining <= 0)
+			return ret;
+
+		/* 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;
+	} 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(sock_net(sk), snum)];
+		spin_lock_bh(&head->lock);
+		sctp_for_each_hentry(pp, &head->chain) {
+			if ((pp->port == snum) && net_eq(pp->net, sock_net(sk)))
+				goto pp_found;
+		}
+	}
+	pp = NULL;
+	goto pp_not_found;
+pp_found:
+	if (!hlist_empty(&pp->owner)) {
+		/* We had a port hash table hit - there is an
+		 * available port (pp != NULL) and it is being
+		 * used by other socket (pp->owner not empty); that other
+		 * socket is going to be sk2.
+		 */
+		struct sock *sk2;
+
+		pr_debug("%s: found a possible match\n", __func__);
+
+		if (pp->fastreuse && reuse && sk->sk_state != SCTP_SS_LISTENING)
+			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.
+		 */
+		sk_for_each_bound(sk2, &pp->owner) {
+			struct sctp_endpoint *ep2;
+			ep2 = sctp_sk(sk2)->ep;
+
+			if (sk == sk2 ||
+			    (reuse && (sk2->sk_reuse || sctp_sk(sk2)->reuse) &&
+			     sk2->sk_state != SCTP_SS_LISTENING))
+				continue;
+
+			if (sctp_bind_addr_conflict(&ep2->base.bind_addr, addr,
+						 sctp_sk(sk2), sctp_sk(sk))) {
+				ret = (long)sk2;
+				goto fail_unlock;
+			}
+		}
+
+		pr_debug("%s: found a match\n", __func__);
+	}
+pp_not_found:
+	/* If there was a hash table miss, create a new port.  */
+	ret = 1;
+	if (!pp && !(pp = sctp_bucket_create(head, sock_net(sk), snum)))
+		goto fail_unlock;
+
+	/* In either case (hit or miss), make sure fastreuse is 1 only
+	 * if sk->sk_reuse is too (that is, if the caller requested
+	 * SO_REUSEADDR on this socket -sk-).
+	 */
+	if (hlist_empty(&pp->owner)) {
+		if (reuse && sk->sk_state != SCTP_SS_LISTENING)
+			pp->fastreuse = 1;
+		else
+			pp->fastreuse = 0;
+	} else if (pp->fastreuse &&
+		   (!reuse || sk->sk_state == SCTP_SS_LISTENING))
+		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:
+	if (!sctp_sk(sk)->bind_hash) {
+		inet_sk(sk)->inet_num = snum;
+		sk_add_bind_node(sk, &pp->owner);
+		sctp_sk(sk)->bind_hash = pp;
+	}
+	ret = 0;
+
+fail_unlock:
+	spin_unlock_bh(&head->lock);
+	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)
+{
+	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->sk_num gets filled in if ephemeral port request. */
+	return !!sctp_get_port_local(sk, &addr);
+}
+
+/*
+ *  Move a socket to LISTENING state.
+ */
+static int sctp_listen_start(struct sock *sk, int backlog)
+{
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
+	struct crypto_shash *tfm = NULL;
+	char alg[32];
+
+	/* Allocate HMAC for generating cookie. */
+	if (!sp->hmac && sp->sctp_hmac_alg) {
+		sprintf(alg, "hmac(%s)", sp->sctp_hmac_alg);
+		tfm = crypto_alloc_shash(alg, 0, 0);
+		if (IS_ERR(tfm)) {
+			net_info_ratelimited("failed to load transform for %s: %ld\n",
+					     sp->sctp_hmac_alg, PTR_ERR(tfm));
+			return -ENOSYS;
+		}
+		sctp_sk(sk)->hmac = tfm;
+	}
+
+	/*
+	 * 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.
+	 *
+	 */
+	inet_sk_set_state(sk, SCTP_SS_LISTENING);
+	if (!ep->base.bind_addr.port) {
+		if (sctp_autobind(sk))
+			return -EAGAIN;
+	} else {
+		if (sctp_get_port(sk, inet_sk(sk)->inet_num)) {
+			inet_sk_set_state(sk, SCTP_SS_CLOSED);
+			return -EADDRINUSE;
+		}
+	}
+
+	sk->sk_max_ack_backlog = backlog;
+	sctp_hash_endpoint(ep);
+	return 0;
+}
+
+/*
+ * 4.1.3 / 5.1.3 listen()
+ *
+ *   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.
+ *
+ *   On TCP style sockets, applications use listen() to ready the SCTP
+ *   endpoint for accepting inbound associations.
+ *
+ *   On both types of endpoints a backlog of '0' disables listening.
+ *
+ *  Move a socket to LISTENING state.
+ */
+int sctp_inet_listen(struct socket *sock, int backlog)
+{
+	struct sock *sk = sock->sk;
+	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
+	int err = -EINVAL;
+
+	if (unlikely(backlog < 0))
+		return err;
+
+	lock_sock(sk);
+
+	/* Peeled-off sockets are not allowed to listen().  */
+	if (sctp_style(sk, UDP_HIGH_BANDWIDTH))
+		goto out;
+
+	if (sock->state != SS_UNCONNECTED)
+		goto out;
+
+	if (!sctp_sstate(sk, LISTENING) && !sctp_sstate(sk, CLOSED))
+		goto out;
+
+	/* If backlog is zero, disable listening. */
+	if (!backlog) {
+		if (sctp_sstate(sk, CLOSED))
+			goto out;
+
+		err = 0;
+		sctp_unhash_endpoint(ep);
+		sk->sk_state = SCTP_SS_CLOSED;
+		if (sk->sk_reuse || sctp_sk(sk)->reuse)
+			sctp_sk(sk)->bind_hash->fastreuse = 1;
+		goto out;
+	}
+
+	/* If we are already listening, just update the backlog */
+	if (sctp_sstate(sk, LISTENING))
+		sk->sk_max_ack_backlog = backlog;
+	else {
+		err = sctp_listen_start(sk, backlog);
+		if (err)
+			goto out;
+	}
+
+	err = 0;
+out:
+	release_sock(sk);
+	return err;
+}
+
+/*
+ * 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_alloc) 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.
+ */
+__poll_t sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	struct sctp_sock *sp = sctp_sk(sk);
+	__poll_t mask;
+
+	poll_wait(file, sk_sleep(sk), wait);
+
+	sock_rps_record_flow(sk);
+
+	/* A TCP-style listening socket becomes readable when the accept queue
+	 * is not empty.
+	 */
+	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
+		return (!list_empty(&sp->ep->asocs)) ?
+			(EPOLLIN | EPOLLRDNORM) : 0;
+
+	mask = 0;
+
+	/* Is there any exceptional events?  */
+	if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
+		mask |= EPOLLERR |
+			(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
+	if (sk->sk_shutdown & RCV_SHUTDOWN)
+		mask |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
+	if (sk->sk_shutdown == SHUTDOWN_MASK)
+		mask |= EPOLLHUP;
+
+	/* Is it readable?  Reconsider this code with TCP-style support.  */
+	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
+		mask |= EPOLLIN | EPOLLRDNORM;
+
+	/* The association is either gone or not ready.  */
+	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
+		return mask;
+
+	/* Is it writable?  */
+	if (sctp_writeable(sk)) {
+		mask |= EPOLLOUT | EPOLLWRNORM;
+	} else {
+		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
+		/*
+		 * 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 |= EPOLLOUT | EPOLLWRNORM;
+	}
+	return mask;
+}
+
+/********************************************************************
+ * 2nd Level Abstractions
+ ********************************************************************/
+
+static struct sctp_bind_bucket *sctp_bucket_create(
+	struct sctp_bind_hashbucket *head, struct net *net, unsigned short snum)
+{
+	struct sctp_bind_bucket *pp;
+
+	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
+	if (pp) {
+		SCTP_DBG_OBJCNT_INC(bind_bucket);
+		pp->port = snum;
+		pp->fastreuse = 0;
+		INIT_HLIST_HEAD(&pp->owner);
+		pp->net = net;
+		hlist_add_head(&pp->node, &head->chain);
+	}
+	return pp;
+}
+
+/* Caller must hold hashbucket lock for this tb with local BH disabled */
+static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
+{
+	if (pp && hlist_empty(&pp->owner)) {
+		__hlist_del(&pp->node);
+		kmem_cache_free(sctp_bucket_cachep, pp);
+		SCTP_DBG_OBJCNT_DEC(bind_bucket);
+	}
+}
+
+/* Release this socket's reference to a local port.  */
+static inline void __sctp_put_port(struct sock *sk)
+{
+	struct sctp_bind_hashbucket *head =
+		&sctp_port_hashtable[sctp_phashfn(sock_net(sk),
+						  inet_sk(sk)->inet_num)];
+	struct sctp_bind_bucket *pp;
+
+	spin_lock(&head->lock);
+	pp = sctp_sk(sk)->bind_hash;
+	__sk_del_bind_node(sk);
+	sctp_sk(sk)->bind_hash = NULL;
+	inet_sk(sk)->inet_num = 0;
+	sctp_bucket_destroy(pp);
+	spin_unlock(&head->lock);
+}
+
+void sctp_put_port(struct sock *sk)
+{
+	local_bh_disable();
+	__sctp_put_port(sk);
+	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;
+	__be16 port;
+
+	/* Initialize a local sockaddr structure to INADDR_ANY. */
+	af = sctp_sk(sk)->pf->af;
+
+	port = htons(inet_sk(sk)->inet_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
+ */
+static int sctp_msghdr_parse(const struct msghdr *msg, struct sctp_cmsgs *cmsgs)
+{
+	struct msghdr *my_msg = (struct msghdr *)msg;
+	struct cmsghdr *cmsg;
+
+	for_each_cmsghdr(cmsg, my_msg) {
+		if (!CMSG_OK(my_msg, cmsg))
+			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
+			 * 5.3.1 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 = CMSG_DATA(cmsg);
+			break;
+
+		case SCTP_SNDRCV:
+			/* SCTP Socket API Extension
+			 * 5.3.2 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->srinfo = CMSG_DATA(cmsg);
+
+			if (cmsgs->srinfo->sinfo_flags &
+			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
+			      SCTP_SACK_IMMEDIATELY | SCTP_SENDALL |
+			      SCTP_PR_SCTP_MASK | SCTP_ABORT | SCTP_EOF))
+				return -EINVAL;
+			break;
+
+		case SCTP_SNDINFO:
+			/* SCTP Socket API Extension
+			 * 5.3.4 SCTP Send Information Structure (SCTP_SNDINFO)
+			 *
+			 * This cmsghdr structure specifies SCTP options for
+			 * sendmsg(). This structure and SCTP_RCVINFO replaces
+			 * SCTP_SNDRCV which has been deprecated.
+			 *
+			 * cmsg_level    cmsg_type      cmsg_data[]
+			 * ------------  ------------   ---------------------
+			 * IPPROTO_SCTP  SCTP_SNDINFO    struct sctp_sndinfo
+			 */
+			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_sndinfo)))
+				return -EINVAL;
+
+			cmsgs->sinfo = CMSG_DATA(cmsg);
+
+			if (cmsgs->sinfo->snd_flags &
+			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
+			      SCTP_SACK_IMMEDIATELY | SCTP_SENDALL |
+			      SCTP_PR_SCTP_MASK | SCTP_ABORT | SCTP_EOF))
+				return -EINVAL;
+			break;
+		case SCTP_PRINFO:
+			/* SCTP Socket API Extension
+			 * 5.3.7 SCTP PR-SCTP Information Structure (SCTP_PRINFO)
+			 *
+			 * This cmsghdr structure specifies SCTP options for sendmsg().
+			 *
+			 * cmsg_level    cmsg_type      cmsg_data[]
+			 * ------------  ------------   ---------------------
+			 * IPPROTO_SCTP  SCTP_PRINFO    struct sctp_prinfo
+			 */
+			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_prinfo)))
+				return -EINVAL;
+
+			cmsgs->prinfo = CMSG_DATA(cmsg);
+			if (cmsgs->prinfo->pr_policy & ~SCTP_PR_SCTP_MASK)
+				return -EINVAL;
+
+			if (cmsgs->prinfo->pr_policy == SCTP_PR_SCTP_NONE)
+				cmsgs->prinfo->pr_value = 0;
+			break;
+		case SCTP_AUTHINFO:
+			/* SCTP Socket API Extension
+			 * 5.3.8 SCTP AUTH Information Structure (SCTP_AUTHINFO)
+			 *
+			 * This cmsghdr structure specifies SCTP options for sendmsg().
+			 *
+			 * cmsg_level    cmsg_type      cmsg_data[]
+			 * ------------  ------------   ---------------------
+			 * IPPROTO_SCTP  SCTP_AUTHINFO  struct sctp_authinfo
+			 */
+			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_authinfo)))
+				return -EINVAL;
+
+			cmsgs->authinfo = CMSG_DATA(cmsg);
+			break;
+		case SCTP_DSTADDRV4:
+		case SCTP_DSTADDRV6:
+			/* SCTP Socket API Extension
+			 * 5.3.9/10 SCTP Destination IPv4/6 Address Structure (SCTP_DSTADDRV4/6)
+			 *
+			 * This cmsghdr structure specifies SCTP options for sendmsg().
+			 *
+			 * cmsg_level    cmsg_type         cmsg_data[]
+			 * ------------  ------------   ---------------------
+			 * IPPROTO_SCTP  SCTP_DSTADDRV4 struct in_addr
+			 * ------------  ------------   ---------------------
+			 * IPPROTO_SCTP  SCTP_DSTADDRV6 struct in6_addr
+			 */
+			cmsgs->addrs_msg = my_msg;
+			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;
+	DEFINE_WAIT(wait);
+
+	prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+
+	/* Socket errors? */
+	error = sock_error(sk);
+	if (error)
+		goto out;
+
+	if (!skb_queue_empty(&sk->sk_receive_queue))
+		goto ready;
+
+	/* Socket shut down?  */
+	if (sk->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) && !sctp_sstate(sk, 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.
+	 */
+	release_sock(sk);
+	*timeo_p = schedule_timeout(*timeo_p);
+	lock_sock(sk);
+
+ready:
+	finish_wait(sk_sleep(sk), &wait);
+	return 0;
+
+interrupted:
+	error = sock_intr_errno(*timeo_p);
+
+out:
+	finish_wait(sk_sleep(sk), &wait);
+	*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.
+ */
+struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
+				       int noblock, int *err)
+{
+	int error;
+	struct sk_buff *skb;
+	long timeo;
+
+	timeo = sock_rcvtimeo(sk, noblock);
+
+	pr_debug("%s: timeo:%ld, max:%ld\n", __func__, 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 correct in any case. 8)
+		 */
+		if (flags & MSG_PEEK) {
+			skb = skb_peek(&sk->sk_receive_queue);
+			if (skb)
+				refcount_inc(&skb->users);
+		} else {
+			skb = __skb_dequeue(&sk->sk_receive_queue);
+		}
+
+		if (skb)
+			return skb;
+
+		/* Caller is allowed not to check sk->sk_err before calling. */
+		error = sock_error(sk);
+		if (error)
+			goto no_packet;
+
+		if (sk->sk_shutdown & RCV_SHUTDOWN)
+			break;
+
+		if (sk_can_busy_loop(sk)) {
+			sk_busy_loop(sk, noblock);
+
+			if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
+				continue;
+		}
+
+		/* 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;
+}
+
+/* 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;
+
+	if (sctp_wspace(asoc) <= 0)
+		return;
+
+	if (waitqueue_active(&asoc->wait))
+		wake_up_interruptible(&asoc->wait);
+
+	if (sctp_writeable(sk)) {
+		struct socket_wq *wq;
+
+		rcu_read_lock();
+		wq = rcu_dereference(sk->sk_wq);
+		if (wq) {
+			if (waitqueue_active(&wq->wait))
+				wake_up_interruptible(&wq->wait);
+
+			/* 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 (!(sk->sk_shutdown & SEND_SHUTDOWN))
+				sock_wake_async(wq, SOCK_WAKE_SPACE, POLL_OUT);
+		}
+		rcu_read_unlock();
+	}
+}
+
+static void sctp_wake_up_waiters(struct sock *sk,
+				 struct sctp_association *asoc)
+{
+	struct sctp_association *tmp = asoc;
+
+	/* We do accounting for the sndbuf space per association,
+	 * so we only need to wake our own association.
+	 */
+	if (asoc->ep->sndbuf_policy)
+		return __sctp_write_space(asoc);
+
+	/* If association goes down and is just flushing its
+	 * outq, then just normally notify others.
+	 */
+	if (asoc->base.dead)
+		return sctp_write_space(sk);
+
+	/* Accounting for the sndbuf space is per socket, so we
+	 * need to wake up others, try to be fair and in case of
+	 * other associations, let them have a go first instead
+	 * of just doing a sctp_write_space() call.
+	 *
+	 * Note that we reach sctp_wake_up_waiters() only when
+	 * associations free up queued chunks, thus we are under
+	 * lock and the list of associations on a socket is
+	 * guaranteed not to change.
+	 */
+	for (tmp = list_next_entry(tmp, asocs); 1;
+	     tmp = list_next_entry(tmp, asocs)) {
+		/* Manually skip the head element. */
+		if (&tmp->asocs == &((sctp_sk(sk))->ep->asocs))
+			continue;
+		/* Wake up association. */
+		__sctp_write_space(tmp);
+		/* We've reached the end. */
+		if (tmp == asoc)
+			break;
+	}
+}
+
+/* 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_chunk *chunk = skb_shinfo(skb)->destructor_arg;
+	struct sctp_association *asoc = chunk->asoc;
+	struct sock *sk = asoc->base.sk;
+
+	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
+				sizeof(struct sk_buff) +
+				sizeof(struct sctp_chunk);
+
+	WARN_ON(refcount_sub_and_test(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc));
+
+	/*
+	 * This undoes what is done via sctp_set_owner_w and sk_mem_charge
+	 */
+	sk->sk_wmem_queued   -= skb->truesize;
+	sk_mem_uncharge(sk, skb->truesize);
+
+	if (chunk->shkey) {
+		struct sctp_shared_key *shkey = chunk->shkey;
+
+		/* refcnt == 2 and !list_empty mean after this release, it's
+		 * not being used anywhere, and it's time to notify userland
+		 * that this shkey can be freed if it's been deactivated.
+		 */
+		if (shkey->deactivated && !list_empty(&shkey->key_list) &&
+		    refcount_read(&shkey->refcnt) == 2) {
+			struct sctp_ulpevent *ev;
+
+			ev = sctp_ulpevent_make_authkey(asoc, shkey->key_id,
+							SCTP_AUTH_FREE_KEY,
+							GFP_KERNEL);
+			if (ev)
+				asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
+		}
+		sctp_auth_shkey_release(chunk->shkey);
+	}
+
+	sock_wfree(skb);
+	sctp_wake_up_waiters(sk, asoc);
+
+	sctp_association_put(asoc);
+}
+
+/* Do accounting for the receive space on the socket.
+ * Accounting for the association is done in ulpevent.c
+ * We set this as a destructor for the cloned data skbs so that
+ * accounting is done at the correct time.
+ */
+void sctp_sock_rfree(struct sk_buff *skb)
+{
+	struct sock *sk = skb->sk;
+	struct sctp_ulpevent *event = sctp_skb2event(skb);
+
+	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
+
+	/*
+	 * Mimic the behavior of sock_rfree
+	 */
+	sk_mem_uncharge(sk, event->rmem_len);
+}
+
+
+/* Helper function to wait for space in the sndbuf.  */
+static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
+				size_t msg_len)
+{
+	struct sock *sk = asoc->base.sk;
+	long current_timeo = *timeo_p;
+	DEFINE_WAIT(wait);
+	int err = 0;
+
+	pr_debug("%s: asoc:%p, timeo:%ld, msg_len:%zu\n", __func__, asoc,
+		 *timeo_p, msg_len);
+
+	/* Increment the association's refcnt.  */
+	sctp_association_hold(asoc);
+
+	/* Wait on the association specific sndbuf space. */
+	for (;;) {
+		prepare_to_wait_exclusive(&asoc->wait, &wait,
+					  TASK_INTERRUPTIBLE);
+		if (asoc->base.dead)
+			goto do_dead;
+		if (!*timeo_p)
+			goto do_nonblock;
+		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING)
+			goto do_error;
+		if (signal_pending(current))
+			goto do_interrupted;
+		if (sk_under_memory_pressure(sk))
+			sk_mem_reclaim(sk);
+		if ((int)msg_len <= sctp_wspace(asoc) &&
+		    sk_wmem_schedule(sk, msg_len))
+			break;
+
+		/* Let another process have a go.  Since we are going
+		 * to sleep anyway.
+		 */
+		release_sock(sk);
+		current_timeo = schedule_timeout(current_timeo);
+		lock_sock(sk);
+		if (sk != asoc->base.sk)
+			goto do_error;
+
+		*timeo_p = current_timeo;
+	}
+
+out:
+	finish_wait(&asoc->wait, &wait);
+
+	/* Release the association's refcnt.  */
+	sctp_association_put(asoc);
+
+	return err;
+
+do_dead:
+	err = -ESRCH;
+	goto out;
+
+do_error:
+	err = -EPIPE;
+	goto out;
+
+do_interrupted:
+	err = sock_intr_errno(*timeo_p);
+	goto out;
+
+do_nonblock:
+	err = -EAGAIN;
+	goto out;
+}
+
+void sctp_data_ready(struct sock *sk)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+	wq = rcu_dereference(sk->sk_wq);
+	if (skwq_has_sleeper(wq))
+		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN |
+						EPOLLRDNORM | EPOLLRDBAND);
+	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
+	rcu_read_unlock();
+}
+
+/* If socket sndbuf has changed, wake up all per association waiters.  */
+void sctp_write_space(struct sock *sk)
+{
+	struct sctp_association *asoc;
+
+	/* Wake up the tasks in each wait queue.  */
+	list_for_each_entry(asoc, &((sctp_sk(sk))->ep->asocs), asocs) {
+		__sctp_write_space(asoc);
+	}
+}
+
+/* Is there any sndbuf space available on the socket?
+ *
+ * Note that sk_wmem_alloc 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 bool sctp_writeable(struct sock *sk)
+{
+	return sk->sk_sndbuf > sk->sk_wmem_queued;
+}
+
+/* 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;
+	DEFINE_WAIT(wait);
+
+	pr_debug("%s: asoc:%p, timeo:%ld\n", __func__, asoc, *timeo_p);
+
+	/* Increment the association's refcnt.  */
+	sctp_association_hold(asoc);
+
+	for (;;) {
+		prepare_to_wait_exclusive(&asoc->wait, &wait,
+					  TASK_INTERRUPTIBLE);
+		if (!*timeo_p)
+			goto do_nonblock;
+		if (sk->sk_shutdown & RCV_SHUTDOWN)
+			break;
+		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
+		    asoc->base.dead)
+			goto do_error;
+		if (signal_pending(current))
+			goto do_interrupted;
+
+		if (sctp_state(asoc, ESTABLISHED))
+			break;
+
+		/* Let another process have a go.  Since we are going
+		 * to sleep anyway.
+		 */
+		release_sock(sk);
+		current_timeo = schedule_timeout(current_timeo);
+		lock_sock(sk);
+
+		*timeo_p = current_timeo;
+	}
+
+out:
+	finish_wait(&asoc->wait, &wait);
+
+	/* Release the association's refcnt.  */
+	sctp_association_put(asoc);
+
+	return err;
+
+do_error:
+	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
+		err = -ETIMEDOUT;
+	else
+		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;
+	DEFINE_WAIT(wait);
+
+	ep = sctp_sk(sk)->ep;
+
+
+	for (;;) {
+		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
+					  TASK_INTERRUPTIBLE);
+
+		if (list_empty(&ep->asocs)) {
+			release_sock(sk);
+			timeo = schedule_timeout(timeo);
+			lock_sock(sk);
+		}
+
+		err = -EINVAL;
+		if (!sctp_sstate(sk, 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;
+	}
+
+	finish_wait(sk_sleep(sk), &wait);
+
+	return err;
+}
+
+static void sctp_wait_for_close(struct sock *sk, long timeout)
+{
+	DEFINE_WAIT(wait);
+
+	do {
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+		if (list_empty(&sctp_sk(sk)->ep->asocs))
+			break;
+		release_sock(sk);
+		timeout = schedule_timeout(timeout);
+		lock_sock(sk);
+	} while (!signal_pending(current) && timeout);
+
+	finish_wait(sk_sleep(sk), &wait);
+}
+
+static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
+{
+	struct sk_buff *frag;
+
+	if (!skb->data_len)
+		goto done;
+
+	/* Don't forget the fragments. */
+	skb_walk_frags(skb, frag)
+		sctp_skb_set_owner_r_frag(frag, sk);
+
+done:
+	sctp_skb_set_owner_r(skb, sk);
+}
+
+void sctp_copy_sock(struct sock *newsk, struct sock *sk,
+		    struct sctp_association *asoc)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct inet_sock *newinet;
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
+
+	newsk->sk_type = sk->sk_type;
+	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
+	newsk->sk_flags = sk->sk_flags;
+	newsk->sk_tsflags = sk->sk_tsflags;
+	newsk->sk_no_check_tx = sk->sk_no_check_tx;
+	newsk->sk_no_check_rx = sk->sk_no_check_rx;
+	newsk->sk_reuse = sk->sk_reuse;
+	sctp_sk(newsk)->reuse = sp->reuse;
+
+	newsk->sk_shutdown = sk->sk_shutdown;
+	newsk->sk_destruct = sctp_destruct_sock;
+	newsk->sk_family = sk->sk_family;
+	newsk->sk_protocol = IPPROTO_SCTP;
+	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
+	newsk->sk_sndbuf = sk->sk_sndbuf;
+	newsk->sk_rcvbuf = sk->sk_rcvbuf;
+	newsk->sk_lingertime = sk->sk_lingertime;
+	newsk->sk_rcvtimeo = sk->sk_rcvtimeo;
+	newsk->sk_sndtimeo = sk->sk_sndtimeo;
+	newsk->sk_rxhash = sk->sk_rxhash;
+
+	newinet = inet_sk(newsk);
+
+	/* Initialize sk's sport, dport, rcv_saddr and daddr for
+	 * getsockname() and getpeername()
+	 */
+	newinet->inet_sport = inet->inet_sport;
+	newinet->inet_saddr = inet->inet_saddr;
+	newinet->inet_rcv_saddr = inet->inet_rcv_saddr;
+	newinet->inet_dport = htons(asoc->peer.port);
+	newinet->pmtudisc = inet->pmtudisc;
+	newinet->inet_id = prandom_u32();
+
+	newinet->uc_ttl = inet->uc_ttl;
+	newinet->mc_loop = 1;
+	newinet->mc_ttl = 1;
+	newinet->mc_index = 0;
+	newinet->mc_list = NULL;
+
+	if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
+		net_enable_timestamp();
+
+	/* Set newsk security attributes from orginal sk and connection
+	 * security attribute from ep.
+	 */
+	security_sctp_sk_clone(ep, sk, newsk);
+}
+
+static inline void sctp_copy_descendant(struct sock *sk_to,
+					const struct sock *sk_from)
+{
+	int ancestor_size = sizeof(struct inet_sock) +
+			    sizeof(struct sctp_sock) -
+			    offsetof(struct sctp_sock, auto_asconf_list);
+
+	if (sk_from->sk_family == PF_INET6)
+		ancestor_size += sizeof(struct ipv6_pinfo);
+
+	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
+}
+
+/* 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,
+			      enum sctp_socket_type type)
+{
+	struct sctp_sock *oldsp = sctp_sk(oldsk);
+	struct sctp_sock *newsp = sctp_sk(newsk);
+	struct sctp_bind_bucket *pp; /* hash list port iterator */
+	struct sctp_endpoint *newep = newsp->ep;
+	struct sk_buff *skb, *tmp;
+	struct sctp_ulpevent *event;
+	struct sctp_bind_hashbucket *head;
+
+	/* Migrate socket buffer sizes and all the socket level options to the
+	 * new socket.
+	 */
+	newsk->sk_sndbuf = oldsk->sk_sndbuf;
+	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
+	/* Brute force copy old sctp opt. */
+	sctp_copy_descendant(newsk, oldsk);
+
+	/* Restore the ep value that was overwritten with the above structure
+	 * copy.
+	 */
+	newsp->ep = newep;
+	newsp->hmac = NULL;
+
+	/* Hook this new socket in to the bind_hash list. */
+	head = &sctp_port_hashtable[sctp_phashfn(sock_net(oldsk),
+						 inet_sk(oldsk)->inet_num)];
+	spin_lock_bh(&head->lock);
+	pp = sctp_sk(oldsk)->bind_hash;
+	sk_add_bind_node(newsk, &pp->owner);
+	sctp_sk(newsk)->bind_hash = pp;
+	inet_sk(newsk)->inet_num = inet_sk(oldsk)->inet_num;
+	spin_unlock_bh(&head->lock);
+
+	/* Copy the bind_addr list from the original endpoint to the new
+	 * endpoint so that we can handle restarts properly
+	 */
+	sctp_bind_addr_dup(&newsp->ep->base.bind_addr,
+				&oldsp->ep->base.bind_addr, GFP_KERNEL);
+
+	sctp_auto_asconf_init(newsp);
+
+	/* 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->sk_receive_queue, tmp) {
+		event = sctp_skb2event(skb);
+		if (event->asoc == assoc) {
+			__skb_unlink(skb, &oldsk->sk_receive_queue);
+			__skb_queue_tail(&newsk->sk_receive_queue, skb);
+			sctp_skb_set_owner_r_frag(skb, newsk);
+		}
+	}
+
+	/* 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 receive_queue.
+	 */
+	skb_queue_head_init(&newsp->pd_lobby);
+	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
+
+	if (atomic_read(&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->sk_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->asoc == assoc) {
+				__skb_unlink(skb, &oldsp->pd_lobby);
+				__skb_queue_tail(queue, skb);
+				sctp_skb_set_owner_r_frag(skb, newsk);
+			}
+		}
+
+		/* Clear up any skbs waiting for the partial
+		 * delivery to finish.
+		 */
+		if (assoc->ulpq.pd_mode)
+			sctp_clear_pd(oldsk, NULL);
+
+	}
+
+	sctp_for_each_rx_skb(assoc, newsk, sctp_skb_set_owner_r_frag);
+
+	/* 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;
+
+	/* Mark the new socket "in-use" by the user so that any packets
+	 * that may arrive on the association after we've moved it are
+	 * queued to the backlog.  This prevents a potential race between
+	 * backlog processing on the old socket and new-packet processing
+	 * on the new socket.
+	 *
+	 * The caller has just allocated newsk so we can guarantee that other
+	 * paths won't try to lock it and then oldsk.
+	 */
+	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
+	sctp_for_each_tx_datachunk(assoc, true, sctp_clear_owner_w);
+	sctp_assoc_migrate(assoc, newsk);
+	sctp_for_each_tx_datachunk(assoc, false, sctp_set_owner_w);
+
+	/* If the association on the newsk is already closed before accept()
+	 * is called, set RCV_SHUTDOWN flag.
+	 */
+	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP)) {
+		inet_sk_set_state(newsk, SCTP_SS_CLOSED);
+		newsk->sk_shutdown |= RCV_SHUTDOWN;
+	} else {
+		inet_sk_set_state(newsk, SCTP_SS_ESTABLISHED);
+	}
+
+	release_sock(newsk);
+}
+
+
+/* This proto struct describes the ULP interface for SCTP.  */
+struct proto sctp_prot = {
+	.name        =	"SCTP",
+	.owner       =	THIS_MODULE,
+	.close       =	sctp_close,
+	.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,
+	.no_autobind =	true,
+	.obj_size    =  sizeof(struct sctp_sock),
+	.useroffset  =  offsetof(struct sctp_sock, subscribe),
+	.usersize    =  offsetof(struct sctp_sock, initmsg) -
+				offsetof(struct sctp_sock, subscribe) +
+				sizeof_field(struct sctp_sock, initmsg),
+	.sysctl_mem  =  sysctl_sctp_mem,
+	.sysctl_rmem =  sysctl_sctp_rmem,
+	.sysctl_wmem =  sysctl_sctp_wmem,
+	.memory_pressure = &sctp_memory_pressure,
+	.enter_memory_pressure = sctp_enter_memory_pressure,
+	.memory_allocated = &sctp_memory_allocated,
+	.sockets_allocated = &sctp_sockets_allocated,
+};
+
+#if IS_ENABLED(CONFIG_IPV6)
+
+#include <net/transp_v6.h>
+static void sctp_v6_destroy_sock(struct sock *sk)
+{
+	sctp_destroy_sock(sk);
+	inet6_destroy_sock(sk);
+}
+
+struct proto sctpv6_prot = {
+	.name		= "SCTPv6",
+	.owner		= THIS_MODULE,
+	.close		= sctp_close,
+	.disconnect	= sctp_disconnect,
+	.accept		= sctp_accept,
+	.ioctl		= sctp_ioctl,
+	.init		= sctp_init_sock,
+	.destroy	= sctp_v6_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,
+	.no_autobind	= true,
+	.obj_size	= sizeof(struct sctp6_sock),
+	.useroffset	= offsetof(struct sctp6_sock, sctp.subscribe),
+	.usersize	= offsetof(struct sctp6_sock, sctp.initmsg) -
+				offsetof(struct sctp6_sock, sctp.subscribe) +
+				sizeof_field(struct sctp6_sock, sctp.initmsg),
+	.sysctl_mem	= sysctl_sctp_mem,
+	.sysctl_rmem	= sysctl_sctp_rmem,
+	.sysctl_wmem	= sysctl_sctp_wmem,
+	.memory_pressure = &sctp_memory_pressure,
+	.enter_memory_pressure = sctp_enter_memory_pressure,
+	.memory_allocated = &sctp_memory_allocated,
+	.sockets_allocated = &sctp_sockets_allocated,
+};
+#endif /* IS_ENABLED(CONFIG_IPV6) */