/*-
 * 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 <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