xref: /freebsd/lib/libc/net/sctp_sys_calls.c (revision db0ac6ded61105caab4700aeac255328d4238dc4)

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * a) Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * b) Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the distribution.
 *
 * c) Neither the name of Cisco Systems, Inc. nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/syscall.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netinet/sctp_uio.h>
#include <netinet/sctp.h>

#ifndef IN6_IS_ADDR_V4MAPPED
#define IN6_IS_ADDR_V4MAPPED(a)		      \
	((*(const uint32_t *)(const void *)(&(a)->s6_addr[0]) == 0) &&	\
	 (*(const uint32_t *)(const void *)(&(a)->s6_addr[4]) == 0) &&	\
	 (*(const uint32_t *)(const void *)(&(a)->s6_addr[8]) == ntohl(0x0000ffff)))
#endif

#define SCTP_CONTROL_VEC_SIZE_RCV  16384


static void
in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
{
	bzero(sin, sizeof(*sin));
	sin->sin_len = sizeof(struct sockaddr_in);
	sin->sin_family = AF_INET;
	sin->sin_port = sin6->sin6_port;
	sin->sin_addr.s_addr = sin6->sin6_addr.__u6_addr.__u6_addr32[3];
}

int
sctp_getaddrlen(sa_family_t family)
{
	int ret, sd;
	socklen_t siz;
	struct sctp_assoc_value av;

	av.assoc_value = family;
	siz = sizeof(av);
#if defined(AF_INET)
	sd = socket(AF_INET, SOCK_SEQPACKET, IPPROTO_SCTP);
#elif defined(AF_INET6)
	sd = socket(AF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP);
#else
	sd = -1;
#endif
	if (sd == -1) {
		return (-1);
	}
	ret = getsockopt(sd, IPPROTO_SCTP, SCTP_GET_ADDR_LEN, &av, &siz);
	close(sd);
	if (ret == 0) {
		return ((int)av.assoc_value);
	} else {
		return (-1);
	}
}

int
sctp_connectx(int sd, const struct sockaddr *addrs, int addrcnt,
    sctp_assoc_t *id)
{
	char *buf;
	int i, ret, *aa;
	char *cpto;
	const struct sockaddr *at;
	size_t len;

	/* validate the address count and list */
	if ((addrs == NULL) || (addrcnt <= 0)) {
		errno = EINVAL;
		return (-1);
	}
	if ((buf = malloc(sizeof(int) + (size_t)addrcnt * sizeof(struct sockaddr_in6))) == NULL) {
		errno = E2BIG;
		return (-1);
	}
	len = sizeof(int);
	at = addrs;
	cpto = buf + sizeof(int);
	/* validate all the addresses and get the size */
	for (i = 0; i < addrcnt; i++) {
		switch (at->sa_family) {
		case AF_INET:
			if (at->sa_len != sizeof(struct sockaddr_in)) {
				free(buf);
				errno = EINVAL;
				return (-1);
			}
			memcpy(cpto, at, sizeof(struct sockaddr_in));
			cpto = ((caddr_t)cpto + sizeof(struct sockaddr_in));
			len += sizeof(struct sockaddr_in);
			break;
		case AF_INET6:
			if (at->sa_len != sizeof(struct sockaddr_in6)) {
				free(buf);
				errno = EINVAL;
				return (-1);
			}
			if (IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)at)->sin6_addr)) {
				in6_sin6_2_sin((struct sockaddr_in *)cpto, (struct sockaddr_in6 *)at);
				cpto = ((caddr_t)cpto + sizeof(struct sockaddr_in));
				len += sizeof(struct sockaddr_in);
			} else {
				memcpy(cpto, at, sizeof(struct sockaddr_in6));
				cpto = ((caddr_t)cpto + sizeof(struct sockaddr_in6));
				len += sizeof(struct sockaddr_in6);
			}
			break;
		default:
			free(buf);
			errno = EINVAL;
			return (-1);
		}
		at = (struct sockaddr *)((caddr_t)at + at->sa_len);
	}
	aa = (int *)buf;
	*aa = addrcnt;
	ret = setsockopt(sd, IPPROTO_SCTP, SCTP_CONNECT_X, (void *)buf,
	    (socklen_t)len);
	if ((ret == 0) && (id != NULL)) {
		*id = *(sctp_assoc_t *)buf;
	}
	free(buf);
	return (ret);
}

int
sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt, int flags)
{
	struct sockaddr *sa;
	struct sockaddr_in *sin;
	struct sockaddr_in6 *sin6;
	int i;
	uint16_t sport;
	bool fix_port;

	/* validate the flags */
	if ((flags != SCTP_BINDX_ADD_ADDR) &&
	    (flags != SCTP_BINDX_REM_ADDR)) {
		errno = EFAULT;
		return (-1);
	}
	/* validate the address count and list */
	if ((addrcnt <= 0) || (addrs == NULL)) {
		errno = EINVAL;
		return (-1);
	}
	sport = 0;
	fix_port = false;
	/* First pre-screen the addresses */
	sa = addrs;
	for (i = 0; i < addrcnt; i++) {
		switch (sa->sa_family) {
		case AF_INET:
			if (sa->sa_len != sizeof(struct sockaddr_in)) {
				errno = EINVAL;
				return (-1);
			}
			sin = (struct sockaddr_in *)sa;
			if (sin->sin_port) {
				/* non-zero port, check or save */
				if (sport) {
					/* Check against our port */
					if (sport != sin->sin_port) {
						errno = EINVAL;
						return (-1);
					}
				} else {
					/* save off the port */
					sport = sin->sin_port;
					fix_port = (i > 0);
				}
			}
			break;
		case AF_INET6:
			if (sa->sa_len != sizeof(struct sockaddr_in6)) {
				errno = EINVAL;
				return (-1);
			}
			sin6 = (struct sockaddr_in6 *)sa;
			if (sin6->sin6_port) {
				/* non-zero port, check or save */
				if (sport) {
					/* Check against our port */
					if (sport != sin6->sin6_port) {
						errno = EINVAL;
						return (-1);
					}
				} else {
					/* save off the port */
					sport = sin6->sin6_port;
					fix_port = (i > 0);
				}
			}
			break;
		default:
			/* Invalid address family specified. */
			errno = EAFNOSUPPORT;
			return (-1);
		}
		sa = (struct sockaddr *)((caddr_t)sa + sa->sa_len);
	}
	sa = addrs;
	for (i = 0; i < addrcnt; i++) {
		/*
		 * Now, if there was a port mentioned, assure that the first
		 * address has that port to make sure it fails or succeeds
		 * correctly.
		 */
		if (fix_port) {
			switch (sa->sa_family) {
			case AF_INET:
				((struct sockaddr_in *)sa)->sin_port = sport;
				break;
			case AF_INET6:
				((struct sockaddr_in6 *)sa)->sin6_port = sport;
				break;
			}
			fix_port = false;
		}
		if (setsockopt(sd, IPPROTO_SCTP, flags, sa, sa->sa_len) != 0) {
			return (-1);
		}
		sa = (struct sockaddr *)((caddr_t)sa + sa->sa_len);
	}
	return (0);
}

int
sctp_opt_info(int sd, sctp_assoc_t id, int opt, void *arg, socklen_t *size)
{
	if (arg == NULL) {
		errno = EINVAL;
		return (-1);
	}
	if ((id == SCTP_CURRENT_ASSOC) ||
	    (id == SCTP_ALL_ASSOC)) {
		errno = EINVAL;
		return (-1);
	}
	switch (opt) {
	case SCTP_RTOINFO:
		((struct sctp_rtoinfo *)arg)->srto_assoc_id = id;
		break;
	case SCTP_ASSOCINFO:
		((struct sctp_assocparams *)arg)->sasoc_assoc_id = id;
		break;
	case SCTP_DEFAULT_SEND_PARAM:
		((struct sctp_assocparams *)arg)->sasoc_assoc_id = id;
		break;
	case SCTP_PRIMARY_ADDR:
		((struct sctp_setprim *)arg)->ssp_assoc_id = id;
		break;
	case SCTP_PEER_ADDR_PARAMS:
		((struct sctp_paddrparams *)arg)->spp_assoc_id = id;
		break;
	case SCTP_MAXSEG:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_AUTH_KEY:
		((struct sctp_authkey *)arg)->sca_assoc_id = id;
		break;
	case SCTP_AUTH_ACTIVE_KEY:
		((struct sctp_authkeyid *)arg)->scact_assoc_id = id;
		break;
	case SCTP_DELAYED_SACK:
		((struct sctp_sack_info *)arg)->sack_assoc_id = id;
		break;
	case SCTP_CONTEXT:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_STATUS:
		((struct sctp_status *)arg)->sstat_assoc_id = id;
		break;
	case SCTP_GET_PEER_ADDR_INFO:
		((struct sctp_paddrinfo *)arg)->spinfo_assoc_id = id;
		break;
	case SCTP_PEER_AUTH_CHUNKS:
		((struct sctp_authchunks *)arg)->gauth_assoc_id = id;
		break;
	case SCTP_LOCAL_AUTH_CHUNKS:
		((struct sctp_authchunks *)arg)->gauth_assoc_id = id;
		break;
	case SCTP_TIMEOUTS:
		((struct sctp_timeouts *)arg)->stimo_assoc_id = id;
		break;
	case SCTP_EVENT:
		((struct sctp_event *)arg)->se_assoc_id = id;
		break;
	case SCTP_DEFAULT_SNDINFO:
		((struct sctp_sndinfo *)arg)->snd_assoc_id = id;
		break;
	case SCTP_DEFAULT_PRINFO:
		((struct sctp_default_prinfo *)arg)->pr_assoc_id = id;
		break;
	case SCTP_PEER_ADDR_THLDS:
		((struct sctp_paddrthlds *)arg)->spt_assoc_id = id;
		break;
	case SCTP_REMOTE_UDP_ENCAPS_PORT:
		((struct sctp_udpencaps *)arg)->sue_assoc_id = id;
		break;
	case SCTP_ECN_SUPPORTED:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_PR_SUPPORTED:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_AUTH_SUPPORTED:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_ASCONF_SUPPORTED:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_RECONFIG_SUPPORTED:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_NRSACK_SUPPORTED:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_PKTDROP_SUPPORTED:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_MAX_BURST:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_ENABLE_STREAM_RESET:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	case SCTP_PR_STREAM_STATUS:
		((struct sctp_prstatus *)arg)->sprstat_assoc_id = id;
		break;
	case SCTP_PR_ASSOC_STATUS:
		((struct sctp_prstatus *)arg)->sprstat_assoc_id = id;
		break;
	case SCTP_MAX_CWND:
		((struct sctp_assoc_value *)arg)->assoc_id = id;
		break;
	default:
		break;
	}
	return (getsockopt(sd, IPPROTO_SCTP, opt, arg, size));
}

int
sctp_getpaddrs(int sd, sctp_assoc_t id, struct sockaddr **raddrs)
{
	struct sctp_getaddresses *addrs;
	struct sockaddr *sa;
	caddr_t lim;
	socklen_t opt_len;
	uint32_t size_of_addresses;
	int cnt;

	if (raddrs == NULL) {
		errno = EFAULT;
		return (-1);
	}
	/* When calling getsockopt(), the value contains the assoc_id. */
	size_of_addresses = (uint32_t)id;
	opt_len = (socklen_t)sizeof(uint32_t);
	if (getsockopt(sd, IPPROTO_SCTP, SCTP_GET_REMOTE_ADDR_SIZE,
	    &size_of_addresses, &opt_len) != 0) {
		if (errno == ENOENT) {
			return (0);
		} else {
			return (-1);
		}
	}
	opt_len = (socklen_t)((size_t)size_of_addresses + sizeof(struct sctp_getaddresses));
	addrs = calloc(1, (size_t)opt_len);
	if (addrs == NULL) {
		errno = ENOMEM;
		return (-1);
	}
	addrs->sget_assoc_id = id;
	/* Now lets get the array of addresses */
	if (getsockopt(sd, IPPROTO_SCTP, SCTP_GET_PEER_ADDRESSES,
	    addrs, &opt_len) != 0) {
		free(addrs);
		return (-1);
	}
	*raddrs = &addrs->addr[0].sa;
	cnt = 0;
	sa = &addrs->addr[0].sa;
	lim = (caddr_t)addrs + opt_len;
	while (((caddr_t)sa < lim) && (sa->sa_len > 0)) {
		sa = (struct sockaddr *)((caddr_t)sa + sa->sa_len);
		cnt++;
	}
	return (cnt);
}

void
sctp_freepaddrs(struct sockaddr *addrs)
{
	void *fr_addr;

	/* Take away the hidden association id */
	fr_addr = (void *)((caddr_t)addrs - offsetof(struct sctp_getaddresses, addr));
	/* Now free it */
	free(fr_addr);
}

int
sctp_getladdrs(int sd, sctp_assoc_t id, struct sockaddr **raddrs)
{
	struct sctp_getaddresses *addrs;
	struct sockaddr *sa;
	caddr_t lim;
	socklen_t opt_len;
	uint32_t size_of_addresses;
	int cnt;

	if (raddrs == NULL) {
		errno = EFAULT;
		return (-1);
	}
	size_of_addresses = 0;
	opt_len = (socklen_t)sizeof(uint32_t);
	if (getsockopt(sd, IPPROTO_SCTP, SCTP_GET_LOCAL_ADDR_SIZE,
	    &size_of_addresses, &opt_len) != 0) {
		return (-1);
	}
	opt_len = (socklen_t)((size_t)size_of_addresses + sizeof(struct sctp_getaddresses));
	addrs = calloc(1, (size_t)opt_len);
	if (addrs == NULL) {
		errno = ENOMEM;
		return (-1);
	}
	addrs->sget_assoc_id = id;
	/* Now lets get the array of addresses */
	if (getsockopt(sd, IPPROTO_SCTP, SCTP_GET_LOCAL_ADDRESSES, addrs,
	    &opt_len) != 0) {
		free(addrs);
		return (-1);
	}
	if (size_of_addresses == 0) {
		free(addrs);
		return (0);
	}
	*raddrs = &addrs->addr[0].sa;
	cnt = 0;
	sa = &addrs->addr[0].sa;
	lim = (caddr_t)addrs + opt_len;
	while (((caddr_t)sa < lim) && (sa->sa_len > 0)) {
		sa = (struct sockaddr *)((caddr_t)sa + sa->sa_len);
		cnt++;
	}
	return (cnt);
}

void
sctp_freeladdrs(struct sockaddr *addrs)
{
	void *fr_addr;

	/* Take away the hidden association id */
	fr_addr = (void *)((caddr_t)addrs - offsetof(struct sctp_getaddresses, addr));
	/* Now free it */
	free(fr_addr);
}

ssize_t
sctp_sendmsg(int s,
    const void *data,
    size_t len,
    const struct sockaddr *to,
    socklen_t tolen,
    uint32_t ppid,
    uint32_t flags,
    uint16_t stream_no,
    uint32_t timetolive,
    uint32_t context)
{
#ifdef SYS_sctp_generic_sendmsg
	struct sctp_sndrcvinfo sinfo;

	memset(&sinfo, 0, sizeof(struct sctp_sndrcvinfo));
	sinfo.sinfo_ppid = ppid;
	sinfo.sinfo_flags = flags;
	sinfo.sinfo_stream = stream_no;
	sinfo.sinfo_timetolive = timetolive;
	sinfo.sinfo_context = context;
	sinfo.sinfo_assoc_id = 0;
	return (syscall(SYS_sctp_generic_sendmsg, s,
	    data, len, to, tolen, &sinfo, 0));
#else
	struct msghdr msg;
	struct sctp_sndrcvinfo *sinfo;
	struct iovec iov;
	char cmsgbuf[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
	struct cmsghdr *cmsg;
	struct sockaddr *who = NULL;
	union {
		struct sockaddr_in in;
		struct sockaddr_in6 in6;
	}     addr;

	if ((tolen > 0) &&
	    ((to == NULL) || (tolen < sizeof(struct sockaddr)))) {
		errno = EINVAL;
		return (-1);
	}
	if ((to != NULL) && (tolen > 0)) {
		switch (to->sa_family) {
		case AF_INET:
			if (tolen != sizeof(struct sockaddr_in)) {
				errno = EINVAL;
				return (-1);
			}
			if ((to->sa_len > 0) &&
			    (to->sa_len != sizeof(struct sockaddr_in))) {
				errno = EINVAL;
				return (-1);
			}
			memcpy(&addr, to, sizeof(struct sockaddr_in));
			addr.in.sin_len = sizeof(struct sockaddr_in);
			break;
		case AF_INET6:
			if (tolen != sizeof(struct sockaddr_in6)) {
				errno = EINVAL;
				return (-1);
			}
			if ((to->sa_len > 0) &&
			    (to->sa_len != sizeof(struct sockaddr_in6))) {
				errno = EINVAL;
				return (-1);
			}
			memcpy(&addr, to, sizeof(struct sockaddr_in6));
			addr.in6.sin6_len = sizeof(struct sockaddr_in6);
			break;
		default:
			errno = EAFNOSUPPORT;
			return (-1);
		}
		who = (struct sockaddr *)&addr;
	}

	iov.iov_base = (char *)data;
	iov.iov_len = len;

	if (who) {
		msg.msg_name = (caddr_t)who;
		msg.msg_namelen = who->sa_len;
	} else {
		msg.msg_name = (caddr_t)NULL;
		msg.msg_namelen = 0;
	}
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_control = cmsgbuf;
	msg.msg_controllen = CMSG_SPACE(sizeof(struct sctp_sndrcvinfo));
	msg.msg_flags = 0;
	cmsg = (struct cmsghdr *)cmsgbuf;
	cmsg->cmsg_level = IPPROTO_SCTP;
	cmsg->cmsg_type = SCTP_SNDRCV;
	cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
	sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
	memset(sinfo, 0, sizeof(struct sctp_sndrcvinfo));
	sinfo->sinfo_stream = stream_no;
	sinfo->sinfo_ssn = 0;
	sinfo->sinfo_flags = flags;
	sinfo->sinfo_ppid = ppid;
	sinfo->sinfo_context = context;
	sinfo->sinfo_assoc_id = 0;
	sinfo->sinfo_timetolive = timetolive;
	return (sendmsg(s, &msg, 0));
#endif
}


sctp_assoc_t
sctp_getassocid(int sd, struct sockaddr *sa)
{
	struct sctp_paddrinfo sp;
	socklen_t siz;

	/* First get the assoc id */
	siz = sizeof(sp);
	memset(&sp, 0, sizeof(sp));
	memcpy((caddr_t)&sp.spinfo_address, sa, sa->sa_len);
	if (getsockopt(sd, IPPROTO_SCTP,
	    SCTP_GET_PEER_ADDR_INFO, &sp, &siz) != 0) {
		/* We depend on the fact that 0 can never be returned */
		return ((sctp_assoc_t)0);
	}
	return (sp.spinfo_assoc_id);
}

ssize_t
sctp_send(int sd, const void *data, size_t len,
    const struct sctp_sndrcvinfo *sinfo,
    int flags)
{

#ifdef SYS_sctp_generic_sendmsg
	struct sockaddr *to = NULL;

	return (syscall(SYS_sctp_generic_sendmsg, sd,
	    data, len, to, 0, sinfo, flags));
#else
	struct msghdr msg;
	struct iovec iov;
	char cmsgbuf[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
	struct cmsghdr *cmsg;

	if (sinfo == NULL) {
		errno = EINVAL;
		return (-1);
	}
	iov.iov_base = (char *)data;
	iov.iov_len = len;

	msg.msg_name = NULL;
	msg.msg_namelen = 0;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_control = cmsgbuf;
	msg.msg_controllen = CMSG_SPACE(sizeof(struct sctp_sndrcvinfo));
	msg.msg_flags = 0;
	cmsg = (struct cmsghdr *)cmsgbuf;
	cmsg->cmsg_level = IPPROTO_SCTP;
	cmsg->cmsg_type = SCTP_SNDRCV;
	cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
	memcpy(CMSG_DATA(cmsg), sinfo, sizeof(struct sctp_sndrcvinfo));
	return (sendmsg(sd, &msg, flags));
#endif
}



ssize_t
sctp_sendx(int sd, const void *msg, size_t msg_len,
    struct sockaddr *addrs, int addrcnt,
    struct sctp_sndrcvinfo *sinfo,
    int flags)
{
	struct sctp_sndrcvinfo __sinfo;
	ssize_t ret;
	int i, cnt, *aa, saved_errno;
	char *buf;
	int no_end_cx = 0;
	size_t len, add_len;
	struct sockaddr *at;

	if (addrs == NULL) {
		errno = EINVAL;
		return (-1);
	}
#ifdef SYS_sctp_generic_sendmsg
	if (addrcnt == 1) {
		socklen_t l;
		ssize_t ret;

		/*
		 * Quick way, we don't need to do a connectx so lets use the
		 * syscall directly.
		 */
		l = addrs->sa_len;
		ret = syscall(SYS_sctp_generic_sendmsg, sd,
		    msg, msg_len, addrs, l, sinfo, flags);
		if ((ret >= 0) && (sinfo != NULL)) {
			sinfo->sinfo_assoc_id = sctp_getassocid(sd, addrs);
		}
		return (ret);
	}
#endif

	len = sizeof(int);
	at = addrs;
	cnt = 0;
	/* validate all the addresses and get the size */
	for (i = 0; i < addrcnt; i++) {
		if (at->sa_family == AF_INET) {
			add_len = sizeof(struct sockaddr_in);
		} else if (at->sa_family == AF_INET6) {
			add_len = sizeof(struct sockaddr_in6);
		} else {
			errno = EINVAL;
			return (-1);
		}
		len += add_len;
		at = (struct sockaddr *)((caddr_t)at + add_len);
		cnt++;
	}
	/* do we have any? */
	if (cnt == 0) {
		errno = EINVAL;
		return (-1);
	}
	buf = malloc(len);
	if (buf == NULL) {
		errno = ENOMEM;
		return (-1);
	}
	aa = (int *)buf;
	*aa = cnt;
	aa++;
	memcpy((caddr_t)aa, addrs, (size_t)(len - sizeof(int)));
	ret = setsockopt(sd, IPPROTO_SCTP, SCTP_CONNECT_X_DELAYED, (void *)buf,
	    (socklen_t)len);

	free(buf);
	if (ret != 0) {
		if (errno == EALREADY) {
			no_end_cx = 1;
			goto continue_send;
		}
		return (ret);
	}
continue_send:
	if (sinfo == NULL) {
		sinfo = &__sinfo;
		memset(&__sinfo, 0, sizeof(__sinfo));
	}
	sinfo->sinfo_assoc_id = sctp_getassocid(sd, addrs);
	if (sinfo->sinfo_assoc_id == 0) {
		(void)setsockopt(sd, IPPROTO_SCTP, SCTP_CONNECT_X_COMPLETE, (void *)addrs,
		    (socklen_t)addrs->sa_len);
		errno = ENOENT;
		return (-1);
	}
	ret = sctp_send(sd, msg, msg_len, sinfo, flags);
	saved_errno = errno;
	if (no_end_cx == 0)
		(void)setsockopt(sd, IPPROTO_SCTP, SCTP_CONNECT_X_COMPLETE, (void *)addrs,
		    (socklen_t)addrs->sa_len);

	errno = saved_errno;
	return (ret);
}

ssize_t
sctp_sendmsgx(int sd,
    const void *msg,
    size_t len,
    struct sockaddr *addrs,
    int addrcnt,
    uint32_t ppid,
    uint32_t flags,
    uint16_t stream_no,
    uint32_t timetolive,
    uint32_t context)
{
	struct sctp_sndrcvinfo sinfo;

	memset((void *)&sinfo, 0, sizeof(struct sctp_sndrcvinfo));
	sinfo.sinfo_ppid = ppid;
	sinfo.sinfo_flags = flags;
	sinfo.sinfo_stream = stream_no;
	sinfo.sinfo_timetolive = timetolive;
	sinfo.sinfo_context = context;
	return (sctp_sendx(sd, msg, len, addrs, addrcnt, &sinfo, 0));
}

ssize_t
sctp_recvmsg(int s,
    void *dbuf,
    size_t len,
    struct sockaddr *from,
    socklen_t *fromlen,
    struct sctp_sndrcvinfo *sinfo,
    int *msg_flags)
{
#ifdef SYS_sctp_generic_recvmsg
	struct iovec iov;

	iov.iov_base = dbuf;
	iov.iov_len = len;
	return (syscall(SYS_sctp_generic_recvmsg, s,
	    &iov, 1, from, fromlen, sinfo, msg_flags));
#else
	ssize_t sz;
	struct msghdr msg;
	struct iovec iov;
	char cmsgbuf[SCTP_CONTROL_VEC_SIZE_RCV];
	struct cmsghdr *cmsg;

	if (msg_flags == NULL) {
		errno = EINVAL;
		return (-1);
	}
	iov.iov_base = dbuf;
	iov.iov_len = len;
	msg.msg_name = (caddr_t)from;
	if (fromlen == NULL)
		msg.msg_namelen = 0;
	else
		msg.msg_namelen = *fromlen;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_control = cmsgbuf;
	msg.msg_controllen = sizeof(cmsgbuf);
	msg.msg_flags = 0;
	sz = recvmsg(s, &msg, *msg_flags);
	*msg_flags = msg.msg_flags;
	if (sz <= 0) {
		return (sz);
	}
	if (sinfo) {
		sinfo->sinfo_assoc_id = 0;
	}
	if ((msg.msg_controllen > 0) && (sinfo != NULL)) {
		/*
		 * parse through and see if we find the sctp_sndrcvinfo (if
		 * the user wants it).
		 */
		for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
			if (cmsg->cmsg_level != IPPROTO_SCTP) {
				continue;
			}
			if (cmsg->cmsg_type == SCTP_SNDRCV) {
				memcpy(sinfo, CMSG_DATA(cmsg), sizeof(struct sctp_sndrcvinfo));
				break;
			}
			if (cmsg->cmsg_type == SCTP_EXTRCV) {
				/*
				 * Let's hope that the user provided enough
				 * enough memory. At least he asked for more
				 * information.
				 */
				memcpy(sinfo, CMSG_DATA(cmsg), sizeof(struct sctp_extrcvinfo));
				break;
			}
		}
	}
	return (sz);
#endif
}

ssize_t
sctp_recvv(int sd,
    const struct iovec *iov,
    int iovlen,
    struct sockaddr *from,
    socklen_t *fromlen,
    void *info,
    socklen_t *infolen,
    unsigned int *infotype,
    int *flags)
{
	char cmsgbuf[SCTP_CONTROL_VEC_SIZE_RCV];
	struct msghdr msg;
	struct cmsghdr *cmsg;
	ssize_t ret;
	struct sctp_rcvinfo *rcvinfo;
	struct sctp_nxtinfo *nxtinfo;

	if (((info != NULL) && (infolen == NULL)) ||
	    ((info == NULL) && (infolen != NULL) && (*infolen != 0)) ||
	    ((info != NULL) && (infotype == NULL))) {
		errno = EINVAL;
		return (-1);
	}
	if (infotype) {
		*infotype = SCTP_RECVV_NOINFO;
	}
	msg.msg_name = from;
	if (fromlen == NULL) {
		msg.msg_namelen = 0;
	} else {
		msg.msg_namelen = *fromlen;
	}
	msg.msg_iov = (struct iovec *)iov;
	msg.msg_iovlen = iovlen;
	msg.msg_control = cmsgbuf;
	msg.msg_controllen = sizeof(cmsgbuf);
	msg.msg_flags = 0;
	ret = recvmsg(sd, &msg, *flags);
	*flags = msg.msg_flags;
	if ((ret > 0) &&
	    (msg.msg_controllen > 0) &&
	    (infotype != NULL) &&
	    (infolen != NULL) &&
	    (*infolen > 0)) {
		rcvinfo = NULL;
		nxtinfo = NULL;
		for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
			if (cmsg->cmsg_level != IPPROTO_SCTP) {
				continue;
			}
			if (cmsg->cmsg_type == SCTP_RCVINFO) {
				rcvinfo = (struct sctp_rcvinfo *)CMSG_DATA(cmsg);
				if (nxtinfo != NULL) {
					break;
				} else {
					continue;
				}
			}
			if (cmsg->cmsg_type == SCTP_NXTINFO) {
				nxtinfo = (struct sctp_nxtinfo *)CMSG_DATA(cmsg);
				if (rcvinfo != NULL) {
					break;
				} else {
					continue;
				}
			}
		}
		if (rcvinfo != NULL) {
			if ((nxtinfo != NULL) && (*infolen >= sizeof(struct sctp_recvv_rn))) {
				struct sctp_recvv_rn *rn_info;

				rn_info = (struct sctp_recvv_rn *)info;
				rn_info->recvv_rcvinfo = *rcvinfo;
				rn_info->recvv_nxtinfo = *nxtinfo;
				*infolen = (socklen_t)sizeof(struct sctp_recvv_rn);
				*infotype = SCTP_RECVV_RN;
			} else if (*infolen >= sizeof(struct sctp_rcvinfo)) {
				memcpy(info, rcvinfo, sizeof(struct sctp_rcvinfo));
				*infolen = (socklen_t)sizeof(struct sctp_rcvinfo);
				*infotype = SCTP_RECVV_RCVINFO;
			}
		} else if (nxtinfo != NULL) {
			if (*infolen >= sizeof(struct sctp_nxtinfo)) {
				memcpy(info, nxtinfo, sizeof(struct sctp_nxtinfo));
				*infolen = (socklen_t)sizeof(struct sctp_nxtinfo);
				*infotype = SCTP_RECVV_NXTINFO;
			}
		}
	}
	return (ret);
}

ssize_t
sctp_sendv(int sd,
    const struct iovec *iov, int iovcnt,
    struct sockaddr *addrs, int addrcnt,
    void *info, socklen_t infolen, unsigned int infotype,
    int flags)
{
	ssize_t ret;
	int i;
	socklen_t addr_len;
	struct msghdr msg;
	in_port_t port;
	struct sctp_sendv_spa *spa_info;
	struct cmsghdr *cmsg;
	char *cmsgbuf;
	struct sockaddr *addr;
	struct sockaddr_in *addr_in;
	struct sockaddr_in6 *addr_in6;
	sctp_assoc_t *assoc_id;

	if ((addrcnt < 0) ||
	    (iovcnt < 0) ||
	    ((addrs == NULL) && (addrcnt > 0)) ||
	    ((addrs != NULL) && (addrcnt == 0)) ||
	    ((iov == NULL) && (iovcnt > 0)) ||
	    ((iov != NULL) && (iovcnt == 0))) {
		errno = EINVAL;
		return (-1);
	}
	cmsgbuf = malloc(CMSG_SPACE(sizeof(struct sctp_sndinfo)) +
	    CMSG_SPACE(sizeof(struct sctp_prinfo)) +
	    CMSG_SPACE(sizeof(struct sctp_authinfo)) +
	    (size_t)addrcnt * CMSG_SPACE(sizeof(struct in6_addr)));
	if (cmsgbuf == NULL) {
		errno = ENOMEM;
		return (-1);
	}
	assoc_id = NULL;
	msg.msg_control = cmsgbuf;
	msg.msg_controllen = 0;
	cmsg = (struct cmsghdr *)cmsgbuf;
	switch (infotype) {
	case SCTP_SENDV_NOINFO:
		if ((infolen != 0) || (info != NULL)) {
			free(cmsgbuf);
			errno = EINVAL;
			return (-1);
		}
		break;
	case SCTP_SENDV_SNDINFO:
		if ((info == NULL) || (infolen < sizeof(struct sctp_sndinfo))) {
			free(cmsgbuf);
			errno = EINVAL;
			return (-1);
		}
		cmsg->cmsg_level = IPPROTO_SCTP;
		cmsg->cmsg_type = SCTP_SNDINFO;
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndinfo));
		memcpy(CMSG_DATA(cmsg), info, sizeof(struct sctp_sndinfo));
		msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_sndinfo));
		cmsg = (struct cmsghdr *)((caddr_t)cmsg + CMSG_SPACE(sizeof(struct sctp_sndinfo)));
		assoc_id = &(((struct sctp_sndinfo *)info)->snd_assoc_id);
		break;
	case SCTP_SENDV_PRINFO:
		if ((info == NULL) || (infolen < sizeof(struct sctp_prinfo))) {
			free(cmsgbuf);
			errno = EINVAL;
			return (-1);
		}
		cmsg->cmsg_level = IPPROTO_SCTP;
		cmsg->cmsg_type = SCTP_PRINFO;
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_prinfo));
		memcpy(CMSG_DATA(cmsg), info, sizeof(struct sctp_prinfo));
		msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_prinfo));
		cmsg = (struct cmsghdr *)((caddr_t)cmsg + CMSG_SPACE(sizeof(struct sctp_prinfo)));
		break;
	case SCTP_SENDV_AUTHINFO:
		if ((info == NULL) || (infolen < sizeof(struct sctp_authinfo))) {
			free(cmsgbuf);
			errno = EINVAL;
			return (-1);
		}
		cmsg->cmsg_level = IPPROTO_SCTP;
		cmsg->cmsg_type = SCTP_AUTHINFO;
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_authinfo));
		memcpy(CMSG_DATA(cmsg), info, sizeof(struct sctp_authinfo));
		msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_authinfo));
		cmsg = (struct cmsghdr *)((caddr_t)cmsg + CMSG_SPACE(sizeof(struct sctp_authinfo)));
		break;
	case SCTP_SENDV_SPA:
		if ((info == NULL) || (infolen < sizeof(struct sctp_sendv_spa))) {
			free(cmsgbuf);
			errno = EINVAL;
			return (-1);
		}
		spa_info = (struct sctp_sendv_spa *)info;
		if (spa_info->sendv_flags & SCTP_SEND_SNDINFO_VALID) {
			cmsg->cmsg_level = IPPROTO_SCTP;
			cmsg->cmsg_type = SCTP_SNDINFO;
			cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndinfo));
			memcpy(CMSG_DATA(cmsg), &spa_info->sendv_sndinfo, sizeof(struct sctp_sndinfo));
			msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_sndinfo));
			cmsg = (struct cmsghdr *)((caddr_t)cmsg + CMSG_SPACE(sizeof(struct sctp_sndinfo)));
			assoc_id = &(spa_info->sendv_sndinfo.snd_assoc_id);
		}
		if (spa_info->sendv_flags & SCTP_SEND_PRINFO_VALID) {
			cmsg->cmsg_level = IPPROTO_SCTP;
			cmsg->cmsg_type = SCTP_PRINFO;
			cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_prinfo));
			memcpy(CMSG_DATA(cmsg), &spa_info->sendv_prinfo, sizeof(struct sctp_prinfo));
			msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_prinfo));
			cmsg = (struct cmsghdr *)((caddr_t)cmsg + CMSG_SPACE(sizeof(struct sctp_prinfo)));
		}
		if (spa_info->sendv_flags & SCTP_SEND_AUTHINFO_VALID) {
			cmsg->cmsg_level = IPPROTO_SCTP;
			cmsg->cmsg_type = SCTP_AUTHINFO;
			cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_authinfo));
			memcpy(CMSG_DATA(cmsg), &spa_info->sendv_authinfo, sizeof(struct sctp_authinfo));
			msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_authinfo));
			cmsg = (struct cmsghdr *)((caddr_t)cmsg + CMSG_SPACE(sizeof(struct sctp_authinfo)));
		}
		break;
	default:
		free(cmsgbuf);
		errno = EINVAL;
		return (-1);
	}
	addr = addrs;
	msg.msg_name = NULL;
	msg.msg_namelen = 0;

	for (i = 0; i < addrcnt; i++) {
		switch (addr->sa_family) {
		case AF_INET:
			addr_len = (socklen_t)sizeof(struct sockaddr_in);
			addr_in = (struct sockaddr_in *)addr;
			if (addr_in->sin_len != addr_len) {
				free(cmsgbuf);
				errno = EINVAL;
				return (-1);
			}
			if (i == 0) {
				port = addr_in->sin_port;
			} else {
				if (port == addr_in->sin_port) {
					cmsg->cmsg_level = IPPROTO_SCTP;
					cmsg->cmsg_type = SCTP_DSTADDRV4;
					cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
					memcpy(CMSG_DATA(cmsg), &addr_in->sin_addr, sizeof(struct in_addr));
					msg.msg_controllen += CMSG_SPACE(sizeof(struct in_addr));
					cmsg = (struct cmsghdr *)((caddr_t)cmsg + CMSG_SPACE(sizeof(struct in_addr)));
				} else {
					free(cmsgbuf);
					errno = EINVAL;
					return (-1);
				}
			}
			break;
		case AF_INET6:
			addr_len = (socklen_t)sizeof(struct sockaddr_in6);
			addr_in6 = (struct sockaddr_in6 *)addr;
			if (addr_in6->sin6_len != addr_len) {
				free(cmsgbuf);
				errno = EINVAL;
				return (-1);
			}
			if (i == 0) {
				port = addr_in6->sin6_port;
			} else {
				if (port == addr_in6->sin6_port) {
					cmsg->cmsg_level = IPPROTO_SCTP;
					cmsg->cmsg_type = SCTP_DSTADDRV6;
					cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_addr));
					memcpy(CMSG_DATA(cmsg), &addr_in6->sin6_addr, sizeof(struct in6_addr));
					msg.msg_controllen += CMSG_SPACE(sizeof(struct in6_addr));
					cmsg = (struct cmsghdr *)((caddr_t)cmsg + CMSG_SPACE(sizeof(struct in6_addr)));
				} else {
					free(cmsgbuf);
					errno = EINVAL;
					return (-1);
				}
			}
			break;
		default:
			free(cmsgbuf);
			errno = EINVAL;
			return (-1);
		}
		if (i == 0) {
			msg.msg_name = addr;
			msg.msg_namelen = addr_len;
		}
		addr = (struct sockaddr *)((caddr_t)addr + addr_len);
	}
	if (msg.msg_controllen == 0) {
		msg.msg_control = NULL;
	}
	msg.msg_iov = (struct iovec *)iov;
	msg.msg_iovlen = iovcnt;
	msg.msg_flags = 0;
	ret = sendmsg(sd, &msg, flags);
	free(cmsgbuf);
	if ((ret >= 0) && (addrs != NULL) && (assoc_id != NULL)) {
		*assoc_id = sctp_getassocid(sd, addrs);
	}
	return (ret);
}


#if !defined(SYS_sctp_peeloff) && !defined(HAVE_SCTP_PEELOFF_SOCKOPT)

int
sctp_peeloff(int sd, sctp_assoc_t assoc_id)
{
	/* NOT supported, return invalid sd */
	errno = ENOTSUP;
	return (-1);
}

#endif
#if defined(SYS_sctp_peeloff) && !defined(HAVE_SCTP_PEELOFF_SOCKOPT)
int
sctp_peeloff(int sd, sctp_assoc_t assoc_id)
{
	return (syscall(SYS_sctp_peeloff, sd, assoc_id));
}

#endif

#undef SCTP_CONTROL_VEC_SIZE_RCV