/*-

 * 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 <netinet/sctp_os.h>

#ifdef INET6

#if defined(__FreeBSD__) && !defined(__Userspace__)

#include <sys/proc.h>

#endif

#include <netinet/sctp_pcb.h>

#include <netinet/sctp_header.h>

#include <netinet/sctp_var.h>

#include <netinet6/sctp6_var.h>

#include <netinet/sctp_sysctl.h>

#include <netinet/sctp_output.h>

#include <netinet/sctp_uio.h>

#include <netinet/sctp_asconf.h>

#include <netinet/sctputil.h>

#include <netinet/sctp_indata.h>

#include <netinet/sctp_timer.h>

#include <netinet/sctp_auth.h>

#include <netinet/sctp_input.h>

#include <netinet/sctp_output.h>

#include <netinet/sctp_bsd_addr.h>

#include <netinet/sctp_crc32.h>

#if !defined(_WIN32)

#include <netinet/icmp6.h>

#include <netinet/udp.h>

#endif

#if defined(__Userspace__)

int ip6_v6only=0;

#endif

#if defined(__Userspace__)

#ifdef INET

void

in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)

{

#if defined(_WIN32)

  uint32_t temp;

#endif

  memset(sin, 0, sizeof(*sin));

#ifdef HAVE_SIN_LEN

  sin->sin_len = sizeof(struct sockaddr_in);

#endif

  sin->sin_family = AF_INET;

  sin->sin_port = sin6->sin6_port;

#if defined(_WIN32)

  temp = sin6->sin6_addr.s6_addr16[7];

  temp = temp << 16;

  temp = temp | sin6->sin6_addr.s6_addr16[6];

  sin->sin_addr.s_addr = temp;

#else

  sin->sin_addr.s_addr = sin6->sin6_addr.s6_addr32[3];

#endif

}

void

in6_sin6_2_sin_in_sock(struct sockaddr *nam)

{

  struct sockaddr_in *sin_p;

  struct sockaddr_in6 sin6;

  /* save original sockaddr_in6 addr and convert it to sockaddr_in  */

  sin6 = *(struct sockaddr_in6 *)nam;

  sin_p = (struct sockaddr_in *)nam;

  in6_sin6_2_sin(sin_p, &sin6);

}

void

in6_sin_2_v4mapsin6(const struct sockaddr_in *sin, struct sockaddr_in6 *sin6)

{

  memset(sin6, 0, sizeof(struct sockaddr_in6));

  sin6->sin6_family = AF_INET6;

#ifdef HAVE_SIN6_LEN

  sin6->sin6_len = sizeof(struct sockaddr_in6);

#endif

  sin6->sin6_port = sin->sin_port;

#if defined(_WIN32)

  ((uint32_t *)&sin6->sin6_addr)[0] = 0;

  ((uint32_t *)&sin6->sin6_addr)[1] = 0;

  ((uint32_t *)&sin6->sin6_addr)[2] = htonl(0xffff);

  ((uint32_t *)&sin6->sin6_addr)[3] = sin->sin_addr.s_addr;

#else

  sin6->sin6_addr.s6_addr32[0] = 0;

  sin6->sin6_addr.s6_addr32[1] = 0;

  sin6->sin6_addr.s6_addr32[2] = htonl(0xffff);

  sin6->sin6_addr.s6_addr32[3] = sin->sin_addr.s_addr;

#endif

}

#endif

#endif

#if !defined(__Userspace__)

int

#if defined(__APPLE__) || defined(__FreeBSD__)

sctp6_input_with_port(struct mbuf **i_pak, int *offp, uint16_t port)

#else

sctp6_input(struct mbuf **i_pak, int *offp, int proto)

#endif

{

  struct mbuf *m;

  int iphlen;

  uint32_t vrf_id;

  uint8_t ecn_bits;

  struct sockaddr_in6 src, dst;

  struct ip6_hdr *ip6;

  struct sctphdr *sh;

  struct sctp_chunkhdr *ch;

  int length, offset;

  uint8_t compute_crc;

#if defined(__FreeBSD__)

  uint32_t mflowid;

  uint8_t mflowtype;

  uint16_t fibnum;

#endif

#if !(defined(__APPLE__) || defined(__FreeBSD__))

  uint16_t port = 0;

#endif

  iphlen = *offp;

  if (SCTP_GET_PKT_VRFID(*i_pak, vrf_id)) {

    SCTP_RELEASE_PKT(*i_pak);

    return (IPPROTO_DONE);

  }

  m = SCTP_HEADER_TO_CHAIN(*i_pak);

#ifdef SCTP_MBUF_LOGGING

  /* Log in any input mbufs */

  if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MBUF_LOGGING_ENABLE) {

    sctp_log_mbc(m, SCTP_MBUF_INPUT);

  }

#endif

#ifdef SCTP_PACKET_LOGGING

  if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LAST_PACKET_TRACING) {

    sctp_packet_log(m);

  }

#endif

#if defined(__FreeBSD__)

  SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,

          "sctp6_input(): Packet of length %d received on %s with csum_flags 0x%b.\n",

          m->m_pkthdr.len,

          if_name(m->m_pkthdr.rcvif),

          (int)m->m_pkthdr.csum_flags, CSUM_BITS);

#endif

#if defined(__APPLE__)

  SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,

          "sctp6_input(): Packet of length %d received on %s%d with csum_flags 0x%x.\n",

          m->m_pkthdr.len,

          m->m_pkthdr.rcvif->if_name,

          m->m_pkthdr.rcvif->if_unit,

          m->m_pkthdr.csum_flags);

#endif

#if defined(_WIN32) && !defined(__Userspace__)

  SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,

          "sctp6_input(): Packet of length %d received on %s with csum_flags 0x%x.\n",

          m->m_pkthdr.len,

          m->m_pkthdr.rcvif->if_xname,

          m->m_pkthdr.csum_flags);

#endif

#if defined(__FreeBSD__)

  mflowid = m->m_pkthdr.flowid;

  mflowtype = M_HASHTYPE_GET(m);

  fibnum = M_GETFIB(m);

#endif

  SCTP_STAT_INCR(sctps_recvpackets);

  SCTP_STAT_INCR_COUNTER64(sctps_inpackets);

  /* Get IP, SCTP, and first chunk header together in the first mbuf. */

  offset = iphlen + sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr);

  if (m->m_len < offset) {

    m = m_pullup(m, offset);

    if (m == NULL) {

      SCTP_STAT_INCR(sctps_hdrops);

      return (IPPROTO_DONE);

    }

  }

  ip6 = mtod(m, struct ip6_hdr *);

  sh = (struct sctphdr *)(mtod(m, caddr_t) + iphlen);

  ch = (struct sctp_chunkhdr *)((caddr_t)sh + sizeof(struct sctphdr));

  offset -= sizeof(struct sctp_chunkhdr);

  memset(&src, 0, sizeof(struct sockaddr_in6));

  src.sin6_family = AF_INET6;

#ifdef HAVE_SIN6_LEN

  src.sin6_len = sizeof(struct sockaddr_in6);

#endif

  src.sin6_port = sh->src_port;

  src.sin6_addr = ip6->ip6_src;

#if defined(__FreeBSD__)

#if defined(__APPLE__)

  /* XXX: This code should also be used on Apple */

#endif

  if (in6_setscope(&src.sin6_addr, m->m_pkthdr.rcvif, NULL) != 0) {

    goto out;

  }

#endif

  memset(&dst, 0, sizeof(struct sockaddr_in6));

  dst.sin6_family = AF_INET6;

#ifdef HAVE_SIN6_LEN

  dst.sin6_len = sizeof(struct sockaddr_in6);

#endif

  dst.sin6_port = sh->dest_port;

  dst.sin6_addr = ip6->ip6_dst;

#if defined(__FreeBSD__)

#if defined(__APPLE__)

  /* XXX: This code should also be used on Apple */

#endif

  if (in6_setscope(&dst.sin6_addr, m->m_pkthdr.rcvif, NULL) != 0) {

    goto out;

  }

#endif

#if defined(__APPLE__)

#if defined(NFAITH) && 0 < NFAITH

  if (faithprefix(&dst.sin6_addr)) {

    goto out;

  }

#endif

#endif

  length = ntohs(ip6->ip6_plen) + iphlen;

  /* Validate mbuf chain length with IP payload length. */

  if (SCTP_HEADER_LEN(m) != length) {

    SCTPDBG(SCTP_DEBUG_INPUT1,

            "sctp6_input() length:%d reported length:%d\n", length, SCTP_HEADER_LEN(m));

    SCTP_STAT_INCR(sctps_hdrops);

    goto out;

  }

  if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {

    goto out;

  }

#if defined(__FreeBSD__)

  ecn_bits = IPV6_TRAFFIC_CLASS(ip6);

  if (m->m_pkthdr.csum_flags & CSUM_SCTP_VALID) {

    SCTP_STAT_INCR(sctps_recvhwcrc);

    compute_crc = 0;

  } else {

#else

  ecn_bits = ((ntohl(ip6->ip6_flow) >> 20) & 0x000000ff);

  if (SCTP_BASE_SYSCTL(sctp_no_csum_on_loopback) &&

      (IN6_ARE_ADDR_EQUAL(&src.sin6_addr, &dst.sin6_addr))) {

    SCTP_STAT_INCR(sctps_recvhwcrc);

    compute_crc = 0;

  } else {

#endif

    SCTP_STAT_INCR(sctps_recvswcrc);

    compute_crc = 1;

  }

  sctp_common_input_processing(&m, iphlen, offset, length,

                               (struct sockaddr *)&src,

                               (struct sockaddr *)&dst,

                               sh, ch,

                               compute_crc,

                               ecn_bits,

#if defined(__FreeBSD__)

                               mflowtype, mflowid, fibnum,

#endif

                               vrf_id, port);

 out:

  if (m) {

    sctp_m_freem(m);

  }

  return (IPPROTO_DONE);

}

#if defined(__APPLE__)

int

sctp6_input(struct mbuf **i_pak, int *offp)

{

  return (sctp6_input_with_port(i_pak, offp, 0));

}

#endif

#if defined(__FreeBSD__)

int

sctp6_input(struct mbuf **i_pak, int *offp, int proto SCTP_UNUSED)

{

  return (sctp6_input_with_port(i_pak, offp, 0));

}

#endif

void

sctp6_notify(struct sctp_inpcb *inp,

             struct sctp_tcb *stcb,

             struct sctp_nets *net,

             uint8_t icmp6_type,

             uint8_t icmp6_code,

             uint32_t next_mtu)

{

#if defined(__APPLE__)

  struct socket *so;

#endif

  int timer_stopped;

  switch (icmp6_type) {

  case ICMP6_DST_UNREACH:

    if ((icmp6_code == ICMP6_DST_UNREACH_NOROUTE) ||

        (icmp6_code == ICMP6_DST_UNREACH_ADMIN) ||

        (icmp6_code == ICMP6_DST_UNREACH_BEYONDSCOPE) ||

        (icmp6_code == ICMP6_DST_UNREACH_ADDR)) {

      /* Mark the net unreachable. */

      if (net->dest_state & SCTP_ADDR_REACHABLE) {

        /* Ok that destination is not reachable */

        net->dest_state &= ~SCTP_ADDR_REACHABLE;

        net->dest_state &= ~SCTP_ADDR_PF;

        sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_DOWN,

                        stcb, 0, (void *)net, SCTP_SO_NOT_LOCKED);

      }

    }

    SCTP_TCB_UNLOCK(stcb);

    break;

  case ICMP6_PARAM_PROB:

    /* Treat it like an ABORT. */

    if (icmp6_code == ICMP6_PARAMPROB_NEXTHEADER) {

      sctp_abort_notification(stcb, true, false, 0, NULL, SCTP_SO_NOT_LOCKED);

#if defined(__APPLE__)

      so = SCTP_INP_SO(inp);

      atomic_add_int(&stcb->asoc.refcnt, 1);

      SCTP_TCB_UNLOCK(stcb);

      SCTP_SOCKET_LOCK(so, 1);

      SCTP_TCB_LOCK(stcb);

      atomic_subtract_int(&stcb->asoc.refcnt, 1);

#endif

      (void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,

                SCTP_FROM_SCTP_USRREQ + SCTP_LOC_2);

#if defined(__APPLE__)

      SCTP_SOCKET_UNLOCK(so, 1);

#endif

    } else {

      SCTP_TCB_UNLOCK(stcb);

    }

    break;

  case ICMP6_PACKET_TOO_BIG:

    if (net->dest_state & SCTP_ADDR_NO_PMTUD) {

      SCTP_TCB_UNLOCK(stcb);

      break;

    }

    if (SCTP_OS_TIMER_PENDING(&net->pmtu_timer.timer)) {

      timer_stopped = 1;

      sctp_timer_stop(SCTP_TIMER_TYPE_PATHMTURAISE, inp, stcb, net,

                      SCTP_FROM_SCTP_USRREQ + SCTP_LOC_1);

    } else {

      timer_stopped = 0;

    }

    /* Update the path MTU. */

    if (net->port) {

      next_mtu -= sizeof(struct udphdr);

    }

    if (net->mtu > next_mtu) {

      net->mtu = next_mtu;

#if defined(__FreeBSD__)

      if (net->port) {

        sctp_hc_set_mtu(&net->ro._l_addr, inp->fibnum, next_mtu + sizeof(struct udphdr));

      } else {

        sctp_hc_set_mtu(&net->ro._l_addr, inp->fibnum, next_mtu);

      }

#endif

    }

    /* Update the association MTU */

    if (stcb->asoc.smallest_mtu > next_mtu) {

      sctp_pathmtu_adjustment(stcb, next_mtu, true);

    }

    /* Finally, start the PMTU timer if it was running before. */

    if (timer_stopped) {

      sctp_timer_start(SCTP_TIMER_TYPE_PATHMTURAISE, inp, stcb, net);

    }

    SCTP_TCB_UNLOCK(stcb);

    break;

  default:

    SCTP_TCB_UNLOCK(stcb);

    break;

  }

}

#if defined(__FreeBSD__) && !defined(__Userspace__)

void

sctp6_ctlinput(struct ip6ctlparam *ip6cp)

{

  struct sctp_inpcb *inp;

  struct sctp_tcb *stcb;

  struct sctp_nets *net;

  struct sctphdr sh;

  struct sockaddr_in6 src, dst;

  if (icmp6_errmap(ip6cp->ip6c_icmp6) == 0) {

    return;

  }

  /*

   * Check if we can safely examine the ports and the

   * verification tag of the SCTP common header.

   */

  if (ip6cp->ip6c_m->m_pkthdr.len <

      (int32_t)(ip6cp->ip6c_off + offsetof(struct sctphdr, checksum))) {

    return;

  }

  /* Copy out the port numbers and the verification tag. */

  memset(&sh, 0, sizeof(sh));

  m_copydata(ip6cp->ip6c_m,

             ip6cp->ip6c_off,

             sizeof(uint16_t) + sizeof(uint16_t) + sizeof(uint32_t),

             (caddr_t)&sh);

  memset(&src, 0, sizeof(struct sockaddr_in6));

  src.sin6_family = AF_INET6;

  src.sin6_len = sizeof(struct sockaddr_in6);

  src.sin6_port = sh.src_port;

  src.sin6_addr = ip6cp->ip6c_ip6->ip6_src;

  if (in6_setscope(&src.sin6_addr, ip6cp->ip6c_m->m_pkthdr.rcvif, NULL) != 0) {

    return;

  }

  memset(&dst, 0, sizeof(struct sockaddr_in6));

  dst.sin6_family = AF_INET6;

  dst.sin6_len = sizeof(struct sockaddr_in6);

  dst.sin6_port = sh.dest_port;

  dst.sin6_addr = ip6cp->ip6c_ip6->ip6_dst;

  if (in6_setscope(&dst.sin6_addr, ip6cp->ip6c_m->m_pkthdr.rcvif, NULL) != 0) {

    return;

  }

  inp = NULL;

  net = NULL;

  stcb = sctp_findassociation_addr_sa((struct sockaddr *)&dst,

                                      (struct sockaddr *)&src,

                                      &inp, &net, 1, SCTP_DEFAULT_VRFID);

  if ((stcb != NULL) &&

      (net != NULL) &&

      (inp != NULL)) {

    /* Check the verification tag */

    if (ntohl(sh.v_tag) != 0) {

      /*

       * This must be the verification tag used for

       * sending out packets. We don't consider

       * packets reflecting the verification tag.

       */

      if (ntohl(sh.v_tag) != stcb->asoc.peer_vtag) {

        SCTP_TCB_UNLOCK(stcb);

        return;

      }

    } else {

      if (ip6cp->ip6c_m->m_pkthdr.len >=

          ip6cp->ip6c_off + sizeof(struct sctphdr) +

                            sizeof(struct sctp_chunkhdr) +

                            offsetof(struct sctp_init, a_rwnd)) {

        /*

         * In this case we can check if we

         * got an INIT chunk and if the

         * initiate tag matches.

         */

        uint32_t initiate_tag;

        uint8_t chunk_type;

        m_copydata(ip6cp->ip6c_m,

                   ip6cp->ip6c_off +

                   sizeof(struct sctphdr),

                   sizeof(uint8_t),

                   (caddr_t)&chunk_type);

        m_copydata(ip6cp->ip6c_m,

                   ip6cp->ip6c_off +

                   sizeof(struct sctphdr) +

                   sizeof(struct sctp_chunkhdr),

                   sizeof(uint32_t),

                   (caddr_t)&initiate_tag);

        if ((chunk_type != SCTP_INITIATION) ||

            (ntohl(initiate_tag) != stcb->asoc.my_vtag)) {

          SCTP_TCB_UNLOCK(stcb);

          return;

        }

      } else {

        SCTP_TCB_UNLOCK(stcb);

        return;

      }

    }

    sctp6_notify(inp, stcb, net,

                 ip6cp->ip6c_icmp6->icmp6_type,

                 ip6cp->ip6c_icmp6->icmp6_code,

                 ntohl(ip6cp->ip6c_icmp6->icmp6_mtu));

  } else {

    if ((stcb == NULL) && (inp != NULL)) {

      /* reduce inp's ref-count */

      SCTP_INP_WLOCK(inp);

      SCTP_INP_DECR_REF(inp);

      SCTP_INP_WUNLOCK(inp);

    }

    if (stcb) {

      SCTP_TCB_UNLOCK(stcb);

    }

  }

}

#else

void

#if defined(__APPLE__) && !defined(APPLE_LEOPARD) && !defined(APPLE_SNOWLEOPARD) && !defined(APPLE_LION) && !defined(APPLE_MOUNTAINLION) && !defined(APPLE_ELCAPITAN)

sctp6_ctlinput(int cmd, struct sockaddr *pktdst, void *d, struct ifnet *ifp SCTP_UNUSED)

#else

sctp6_ctlinput(int cmd, struct sockaddr *pktdst, void *d)

#endif

{

  struct ip6ctlparam *ip6cp;

  struct sctp_inpcb *inp;

  struct sctp_tcb *stcb;

  struct sctp_nets *net;

  struct sctphdr sh;

  struct sockaddr_in6 src, dst;

#ifdef HAVE_SA_LEN

  if (pktdst->sa_family != AF_INET6 ||

      pktdst->sa_len != sizeof(struct sockaddr_in6)) {

#else

  if (pktdst->sa_family != AF_INET6) {

#endif

    return;

  }

  if ((unsigned)cmd >= PRC_NCMDS) {

    return;

  }

  if (PRC_IS_REDIRECT(cmd)) {

    d = NULL;

  } else if (inet6ctlerrmap[cmd] == 0) {

    return;

  }

  /* If the parameter is from icmp6, decode it. */

  if (d != NULL) {

    ip6cp = (struct ip6ctlparam *)d;

  } else {

    ip6cp = (struct ip6ctlparam *)NULL;

  }

  if (ip6cp != NULL) {

    /*

     * XXX: We assume that when IPV6 is non NULL, M and OFF are

     * valid.

     */

    if (ip6cp->ip6c_m == NULL) {

      return;

    }

    /* Check if we can safely examine the ports and the

     * verification tag of the SCTP common header.

     */

    if (ip6cp->ip6c_m->m_pkthdr.len <

        (int32_t)(ip6cp->ip6c_off + offsetof(struct sctphdr, checksum))) {

      return;

    }

    /* Copy out the port numbers and the verification tag. */

    memset(&sh, 0, sizeof(sh));

    m_copydata(ip6cp->ip6c_m,

               ip6cp->ip6c_off,

               sizeof(uint16_t) + sizeof(uint16_t) + sizeof(uint32_t),

               (caddr_t)&sh);

    memset(&src, 0, sizeof(struct sockaddr_in6));

    src.sin6_family = AF_INET6;

#ifdef HAVE_SIN6_LEN

    src.sin6_len = sizeof(struct sockaddr_in6);

#endif

    src.sin6_port = sh.src_port;

    src.sin6_addr = ip6cp->ip6c_ip6->ip6_src;

    memset(&dst, 0, sizeof(struct sockaddr_in6));

    dst.sin6_family = AF_INET6;

#ifdef HAVE_SIN6_LEN

    dst.sin6_len = sizeof(struct sockaddr_in6);

#endif

    dst.sin6_port = sh.dest_port;

    dst.sin6_addr = ip6cp->ip6c_ip6->ip6_dst;

    inp = NULL;

    net = NULL;

    stcb = sctp_findassociation_addr_sa((struct sockaddr *)&dst,

                                        (struct sockaddr *)&src,

                                        &inp, &net, 1, SCTP_DEFAULT_VRFID);

    if ((stcb != NULL) &&

        (net != NULL) &&

        (inp != NULL)) {

      /* Check the verification tag */

      if (ntohl(sh.v_tag) != 0) {

        /*

         * This must be the verification tag used for

         * sending out packets. We don't consider

         * packets reflecting the verification tag.

         */

        if (ntohl(sh.v_tag) != stcb->asoc.peer_vtag) {

          SCTP_TCB_UNLOCK(stcb);

          return;

        }

      } else {

        SCTP_TCB_UNLOCK(stcb);

        return;

      }

      sctp6_notify(inp, stcb, net,

                   ip6cp->ip6c_icmp6->icmp6_type,

                   ip6cp->ip6c_icmp6->icmp6_code,

                   ntohl(ip6cp->ip6c_icmp6->icmp6_mtu));

#if defined(__Userspace__)

      if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) == 0) &&

          (stcb->sctp_socket != NULL)) {

        struct socket *upcall_socket;

        upcall_socket = stcb->sctp_socket;

        SOCK_LOCK(upcall_socket);

        soref(upcall_socket);

        SOCK_UNLOCK(upcall_socket);

        if ((upcall_socket->so_upcall != NULL) &&

            (upcall_socket->so_error != 0)) {

          (*upcall_socket->so_upcall)(upcall_socket, upcall_socket->so_upcallarg, M_NOWAIT);

        }

        ACCEPT_LOCK();

        SOCK_LOCK(upcall_socket);

        sorele(upcall_socket);

      }

#endif

    } else {

      if ((stcb == NULL) && (inp != NULL)) {

        /* reduce inp's ref-count */

        SCTP_INP_WLOCK(inp);

        SCTP_INP_DECR_REF(inp);

        SCTP_INP_WUNLOCK(inp);

      }

      if (stcb) {

        SCTP_TCB_UNLOCK(stcb);

      }

    }

  }

}

#endif

#endif

/*

 * this routine can probably be collapsed into the one in sctp_userreq.c

 * since they do the same thing and now we lookup with a sockaddr

 */

#if defined(__FreeBSD__) && !defined(__Userspace__)

static int

sctp6_getcred(SYSCTL_HANDLER_ARGS)

{

  struct xucred xuc;

  struct sockaddr_in6 addrs[2];

  struct sctp_inpcb *inp;

  struct sctp_nets *net;

  struct sctp_tcb *stcb;

  int error;

  uint32_t vrf_id;

  vrf_id = SCTP_DEFAULT_VRFID;

#if defined(__FreeBSD__) && !defined(__Userspace__)

  error = priv_check(req->td, PRIV_NETINET_GETCRED);

#else

  error = suser(req->p);

#endif

  if (error)

    return (error);

  if (req->newlen != sizeof(addrs)) {

    SCTP_LTRACE_ERR_RET(NULL, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

    return (EINVAL);

  }

  if (req->oldlen != sizeof(struct ucred)) {

    SCTP_LTRACE_ERR_RET(NULL, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

    return (EINVAL);

  }

  error = SYSCTL_IN(req, addrs, sizeof(addrs));

  if (error)

    return (error);

  stcb = sctp_findassociation_addr_sa(sin6tosa(&addrs[1]),

      sin6tosa(&addrs[0]),

      &inp, &net, 1, vrf_id);

  if (stcb == NULL || inp == NULL || inp->sctp_socket == NULL) {

    if ((inp != NULL) && (stcb == NULL)) {

      /* reduce ref-count */

      SCTP_INP_WLOCK(inp);

      SCTP_INP_DECR_REF(inp);

      goto cred_can_cont;

    }

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, ENOENT);

    error = ENOENT;

    goto out;

  }

  SCTP_TCB_UNLOCK(stcb);

  /* We use the write lock here, only

   * since in the error leg we need it.

   * If we used RLOCK, then we would have

   * to wlock/decr/unlock/rlock. Which

   * in theory could create a hole. Better

   * to use higher wlock.

   */

  SCTP_INP_WLOCK(inp);

 cred_can_cont:

  error = cr_canseesocket(req->td->td_ucred, inp->sctp_socket);

  if (error) {

    SCTP_INP_WUNLOCK(inp);

    goto out;

  }

  cru2x(inp->sctp_socket->so_cred, &xuc);

  SCTP_INP_WUNLOCK(inp);

  error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));

out:

  return (error);

}

SYSCTL_PROC(_net_inet6_sctp6, OID_AUTO, getcred,

    CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_NEEDGIANT,

    0, 0, sctp6_getcred, "S,ucred",

    "Get the ucred of a SCTP6 connection");

#endif

#if defined(__Userspace__)

int

sctp6_attach(struct socket *so, int proto SCTP_UNUSED, uint32_t vrf_id)

#elif defined(__FreeBSD__)

static int

sctp6_attach(struct socket *so, int proto SCTP_UNUSED, struct thread *p SCTP_UNUSED)

#elif defined(_WIN32)

static int

sctp6_attach(struct socket *so, int proto SCTP_UNUSED, PKTHREAD p SCTP_UNUSED)

#else

static int

sctp6_attach(struct socket *so, int proto SCTP_UNUSED, struct proc *p SCTP_UNUSED)

#endif

{

  int error;

  struct sctp_inpcb *inp;

#if !defined(__Userspace__)

  uint32_t vrf_id = SCTP_DEFAULT_VRFID;

#endif

  inp = (struct sctp_inpcb *)so->so_pcb;

  if (inp != NULL) {

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

    return (EINVAL);

  }

  if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {

    error = SCTP_SORESERVE(so, SCTP_BASE_SYSCTL(sctp_sendspace), SCTP_BASE_SYSCTL(sctp_recvspace));

    if (error)

      return (error);

  }

  error = sctp_inpcb_alloc(so, vrf_id);

  if (error)

    return (error);

  inp = (struct sctp_inpcb *)so->so_pcb;

  SCTP_INP_WLOCK(inp);

  inp->sctp_flags |= SCTP_PCB_FLAGS_BOUND_V6; /* I'm v6! */

  inp->ip_inp.inp.inp_vflag |= INP_IPV6;

  inp->ip_inp.inp.in6p_hops = -1;  /* use kernel default */

  inp->ip_inp.inp.in6p_cksum = -1;  /* just to be sure */

#ifdef INET

  /*

   * XXX: ugly!! IPv4 TTL initialization is necessary for an IPv6

   * socket as well, because the socket may be bound to an IPv6

   * wildcard address, which may match an IPv4-mapped IPv6 address.

   */

  inp->ip_inp.inp.inp_ip_ttl = MODULE_GLOBAL(ip_defttl);

#endif

  SCTP_INP_WUNLOCK(inp);

  return (0);

}

#if defined(__Userspace__)

int

sctp6_bind(struct socket *so, struct sockaddr *addr, void * p)

{

#elif defined(__FreeBSD__)

static int

sctp6_bind(struct socket *so, struct sockaddr *addr, struct thread *p)

{

#elif defined(__APPLE__)

static int

sctp6_bind(struct socket *so, struct sockaddr *addr, struct proc *p)

{

#elif defined(_WIN32)

static int

sctp6_bind(struct socket *so, struct sockaddr *addr, PKTHREAD p)

{

#else

static int

sctp6_bind(struct socket *so, struct mbuf *nam, struct proc *p)

{

  struct sockaddr *addr = nam ? mtod(nam, struct sockaddr *): NULL;

#endif

  struct sctp_inpcb *inp;

  int error;

  u_char vflagsav;

  inp = (struct sctp_inpcb *)so->so_pcb;

  if (inp == NULL) {

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

    return (EINVAL);

  }

#if !(defined(_WIN32) && !defined(__Userspace__))

  if (addr) {

    switch (addr->sa_family) {

#ifdef INET

    case AF_INET:

#ifdef HAVE_SA_LEN

      if (addr->sa_len != sizeof(struct sockaddr_in)) {

        SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

        return (EINVAL);

      }

#endif

      break;

#endif

#ifdef INET6

    case AF_INET6:

#ifdef HAVE_SA_LEN

      if (addr->sa_len != sizeof(struct sockaddr_in6)) {

        SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

        return (EINVAL);

      }

#endif

      break;

#endif

    default:

      SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

      return (EINVAL);

    }

  }

#endif

  vflagsav = inp->ip_inp.inp.inp_vflag;

  inp->ip_inp.inp.inp_vflag &= ~INP_IPV4;

  inp->ip_inp.inp.inp_vflag |= INP_IPV6;

  if ((addr != NULL) && (SCTP_IPV6_V6ONLY(inp) == 0)) {

    switch (addr->sa_family) {

#ifdef INET

    case AF_INET:

      /* binding v4 addr to v6 socket, so reset flags */

      inp->ip_inp.inp.inp_vflag |= INP_IPV4;

      inp->ip_inp.inp.inp_vflag &= ~INP_IPV6;

      break;

#endif

#ifdef INET6

    case AF_INET6:

    {

      struct sockaddr_in6 *sin6_p;

      sin6_p = (struct sockaddr_in6 *)addr;

      if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr)) {

        inp->ip_inp.inp.inp_vflag |= INP_IPV4;

      }

#ifdef INET

      if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {

        struct sockaddr_in sin;

        in6_sin6_2_sin(&sin, sin6_p);

        inp->ip_inp.inp.inp_vflag |= INP_IPV4;

        inp->ip_inp.inp.inp_vflag &= ~INP_IPV6;

        error = sctp_inpcb_bind(so, (struct sockaddr *)&sin, NULL, p);

        goto out;

      }

#endif

      break;

    }

#endif

    default:

      break;

    }

  } else if (addr != NULL) {

    struct sockaddr_in6 *sin6_p;

    /* IPV6_V6ONLY socket */

#ifdef INET

    if (addr->sa_family == AF_INET) {

      /* can't bind v4 addr to v6 only socket! */

      SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

      error = EINVAL;

      goto out;

    }

#endif

    sin6_p = (struct sockaddr_in6 *)addr;

    if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {

      /* can't bind v4-mapped addrs either! */

      /* NOTE: we don't support SIIT */

      SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

      error = EINVAL;

      goto out;

    }

  }

  error = sctp_inpcb_bind(so, addr, NULL, p);

out:

  if (error != 0)

    inp->ip_inp.inp.inp_vflag = vflagsav;

  return (error);

}

#if defined(__FreeBSD__) || defined(_WIN32) || defined(__Userspace__)

#if !defined(__Userspace__)

static void

#else

void

#endif

sctp6_close(struct socket *so)

{

  sctp_close(so);

}

/* This could be made common with sctp_detach() since they are identical */

#else

static

int

sctp6_detach(struct socket *so)

{

#if defined(__Userspace__)

  sctp_close(so);

  return (0);

#else

  return (sctp_detach(so));

#endif

}

#endif

int

#if defined(__FreeBSD__) && !defined(__Userspace__)

sctp_sendm(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,

    struct mbuf *control, struct thread *p);

#else

sctp_sendm(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,

    struct mbuf *control, struct proc *p);

#endif

#if !defined(_WIN32) && !defined(__Userspace__)

#if defined(__FreeBSD__)

static int

sctp6_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,

    struct mbuf *control, struct thread *p)

{

#elif defined(__APPLE__)

static int

sctp6_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,

    struct mbuf *control, struct proc *p)

{

#else

static int

sctp6_send(struct socket *so, int flags, struct mbuf *m, struct mbuf *nam,

    struct mbuf *control, struct proc *p)

{

  struct sockaddr *addr = nam ? mtod(nam, struct sockaddr *): NULL;

#endif

  struct sctp_inpcb *inp;

#ifdef INET

  struct sockaddr_in6 *sin6;

#endif /* INET */

  /* No SPL needed since sctp_output does this */

  inp = (struct sctp_inpcb *)so->so_pcb;

  if (inp == NULL) {

    if (control) {

      SCTP_RELEASE_PKT(control);

      control = NULL;

    }

    SCTP_RELEASE_PKT(m);

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

    return (EINVAL);

  }

  /*

   * For the TCP model we may get a NULL addr, if we are a connected

   * socket thats ok.

   */

  if ((inp->sctp_flags & SCTP_PCB_FLAGS_CONNECTED) &&

      (addr == NULL)) {

    goto connected_type;

  }

  if (addr == NULL) {

    SCTP_RELEASE_PKT(m);

    if (control) {

      SCTP_RELEASE_PKT(control);

      control = NULL;

    }

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EDESTADDRREQ);

    return (EDESTADDRREQ);

  }

  switch (addr->sa_family) {

#ifdef INET

  case AF_INET:

#if defined(HAVE_SA_LEN)

    if (addr->sa_len != sizeof(struct sockaddr_in)) {

      if (control) {

        SCTP_RELEASE_PKT(control);

        control = NULL;

      }

      SCTP_RELEASE_PKT(m);

      SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

      return (EINVAL);

    }

#endif

    break;

#endif

#ifdef INET6

  case AF_INET6:

#if defined(HAVE_SA_LEN)

    if (addr->sa_len != sizeof(struct sockaddr_in6)) {

      if (control) {

        SCTP_RELEASE_PKT(control);

        control = NULL;

      }

      SCTP_RELEASE_PKT(m);

      SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

      return (EINVAL);

    }

#endif

    break;

#endif

  default:

    if (control) {

      SCTP_RELEASE_PKT(control);

      control = NULL;

    }

    SCTP_RELEASE_PKT(m);

    SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

    return (EINVAL);

  }

#ifdef INET

  sin6 = (struct sockaddr_in6 *)addr;

  if (SCTP_IPV6_V6ONLY(inp)) {

    /*

     * if IPV6_V6ONLY flag, we discard datagrams destined to a

     * v4 addr or v4-mapped addr

     */

    if (addr->sa_family == AF_INET) {

      if (control) {

        SCTP_RELEASE_PKT(control);

        control = NULL;

      }

      SCTP_RELEASE_PKT(m);

      SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

      return (EINVAL);

    }

    if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {

      if (control) {

        SCTP_RELEASE_PKT(control);

        control = NULL;

      }

      SCTP_RELEASE_PKT(m);

      SCTP_LTRACE_ERR_RET(inp, NULL, NULL, SCTP_FROM_SCTP6_USRREQ, EINVAL);

      return (EINVAL);

    }

  }

  if ((addr->sa_family == AF_INET6) &&

      IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {

    struct sockaddr_in sin;

    /* convert v4-mapped into v4 addr and send */

    in6_sin6_2_sin(&sin, sin6);

    return (sctp_sendm(so, flags, m, (struct sockaddr *)&sin, control, p));

  }

#endif        /* INET */

connected_type:

  /* now what about control */

  if (control) {

    if (inp->control) {

      SCTP_PRINTF("huh? control set?\n");

      SCTP_RELEASE_PKT(inp->control);

      inp->control = NULL;

    }

    inp->control = control;