// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * PIM for Quagga

 * Copyright (C) 2015 Cumulus Networks, Inc.

 * Donald Sharp

 */

#include <zebra.h>

#include "log.h"

#include "if.h"

#include "frrevent.h"

#include "prefix.h"

#include "vty.h"

#include "plist.h"

#include "pimd.h"

#include "pim_mroute.h"

#include "pim_iface.h"

#include "pim_msg.h"

#include "pim_pim.h"

#include "pim_str.h"

#include "pim_rp.h"

#include "pim_register.h"

#include "pim_upstream.h"

#include "pim_rpf.h"

#include "pim_oil.h"

#include "pim_zebra.h"

#include "pim_join.h"

#include "pim_util.h"

#include "pim_ssm.h"

#include "pim_vxlan.h"

#include "pim_addr.h"

struct event *send_test_packet_timer = NULL;

void pim_register_join(struct pim_upstream *up)

{

  struct pim_instance *pim = up->channel_oil->pim;

  if (pim_is_grp_ssm(pim, up->sg.grp)) {

    if (PIM_DEBUG_PIM_EVENTS)

      zlog_debug("%s register setup skipped as group is SSM",

           up->sg_str);

    return;

  }

  pim_channel_add_oif(up->channel_oil, pim->regiface,

          PIM_OIF_FLAG_PROTO_PIM, __func__);

  up->reg_state = PIM_REG_JOIN;

  pim_vxlan_update_sg_reg_state(pim, up, true);

}

void pim_register_stop_send(struct interface *ifp, pim_sgaddr *sg, pim_addr src,

          pim_addr originator)

{

  struct pim_interface *pinfo;

  unsigned char buffer[10000];

  unsigned int b1length = 0;

  unsigned int length;

  uint8_t *b1;

  if (PIM_DEBUG_PIM_REG) {

    zlog_debug("Sending Register stop for %pSG to %pPA on %s", sg,

         &originator, ifp->name);

  }

  memset(buffer, 0, 10000);

  b1 = (uint8_t *)buffer + PIM_MSG_REGISTER_STOP_LEN;

  length = pim_encode_addr_group(b1, AFI_IP, 0, 0, sg->grp);

  b1length += length;

  b1 += length;

  length = pim_encode_addr_ucast(b1, sg->src);

  b1length += length;

  pim_msg_build_header(src, originator, buffer,

           b1length + PIM_MSG_REGISTER_STOP_LEN,

           PIM_MSG_TYPE_REG_STOP, false);

  pinfo = (struct pim_interface *)ifp->info;

  if (!pinfo) {

    if (PIM_DEBUG_PIM_TRACE)

      zlog_debug("%s: No pinfo!", __func__);

    return;

  }

  if (pim_msg_send(pinfo->pim_sock_fd, src, originator, buffer,

       b1length + PIM_MSG_REGISTER_STOP_LEN, ifp)) {

    if (PIM_DEBUG_PIM_TRACE) {

      zlog_debug(

        "%s: could not send PIM register stop message on interface %s",

        __func__, ifp->name);

    }

  }

  if (!pinfo->pim_passive_enable)

    ++pinfo->pim_ifstat_reg_stop_send;

}

static void pim_reg_stop_upstream(struct pim_instance *pim,

          struct pim_upstream *up)

{

  switch (up->reg_state) {

  case PIM_REG_NOINFO:

  case PIM_REG_PRUNE:

    return;

  case PIM_REG_JOIN:

    up->reg_state = PIM_REG_PRUNE;

    pim_channel_del_oif(up->channel_oil, pim->regiface,

            PIM_OIF_FLAG_PROTO_PIM, __func__);

    pim_upstream_start_register_stop_timer(up, 0);

    pim_vxlan_update_sg_reg_state(pim, up, false);

    break;

  case PIM_REG_JOIN_PENDING:

    up->reg_state = PIM_REG_PRUNE;

    pim_upstream_start_register_stop_timer(up, 0);

    return;

  }

}

int pim_register_stop_recv(struct interface *ifp, uint8_t *buf, int buf_size)

{

  struct pim_interface *pim_ifp = ifp->info;

  struct pim_instance *pim = pim_ifp->pim;

  struct pim_upstream *up = NULL;

  struct pim_rpf *rp;

  pim_sgaddr sg;

  struct listnode *up_node;

  struct pim_upstream *child;

  bool wrong_af = false;

  bool handling_star = false;

  int l;

  if (pim_ifp->pim_passive_enable) {

    if (PIM_DEBUG_PIM_PACKETS)

      zlog_debug(

        "skip receiving PIM message on passive interface %s",

        ifp->name);

    return 0;

  }

  ++pim_ifp->pim_ifstat_reg_stop_recv;

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

  l = pim_parse_addr_group(&sg, buf, buf_size);

  buf += l;

  buf_size -= l;

  pim_parse_addr_ucast(&sg.src, buf, buf_size, &wrong_af);

  if (wrong_af) {

    zlog_err("invalid AF in Register-Stop on %s", ifp->name);

    return -1;

  }

  if (PIM_DEBUG_PIM_REG)

    zlog_debug("Received Register stop for %pSG", &sg);

  rp = RP(pim_ifp->pim, sg.grp);

  if (rp) {

    /* As per RFC 7761, Section 4.9.4:

     * A special wildcard value consisting of an address field of

     * all zeros can be used to indicate any source.

     */

    if ((pim_addr_cmp(sg.src, rp->rpf_addr) == 0) ||

        pim_addr_is_any(sg.src)) {

      handling_star = true;

      sg.src = PIMADDR_ANY;

    }

  }

  /*

   * RFC 7761 Sec 4.4.1

   * Handling Register-Stop(*,G) Messages at the DR:

   *   A Register-Stop(*,G) should be treated as a

   *   Register-Stop(S,G) for all (S,G) Register state

   *   machines that are not in the NoInfo state.

   */

  up = pim_upstream_find(pim, &sg);

  if (up) {

    /*

     * If the upstream find actually found a particular

     * S,G then we *know* that the following for loop

     * is not going to execute and this is ok

     */

    for (ALL_LIST_ELEMENTS_RO(up->sources, up_node, child)) {

      if (PIM_DEBUG_PIM_REG)

        zlog_debug("Executing Reg stop for %s",

             child->sg_str);

      pim_reg_stop_upstream(pim, child);

    }

    if (PIM_DEBUG_PIM_REG)

      zlog_debug("Executing Reg stop for %s", up->sg_str);

    pim_reg_stop_upstream(pim, up);

  } else {

    if (!handling_star)

      return 0;

    /*

     * Unfortunately pim was unable to find a *,G

     * but pim may still actually have individual

     * S,G's that need to be processed.  In that

     * case pim must do the expensive walk to find

     * and stop

     */

    frr_each (rb_pim_upstream, &pim->upstream_head, up) {

      if (pim_addr_cmp(up->sg.grp, sg.grp) == 0) {

        if (PIM_DEBUG_PIM_REG)

          zlog_debug("Executing Reg stop for %s",

               up->sg_str);

        pim_reg_stop_upstream(pim, up);

      }

    }

  }

  return 0;

}

#if PIM_IPV == 6

struct in6_addr pim_register_get_unicast_v6_addr(struct pim_interface *p_ifp)

{

  struct listnode *node;

  struct listnode *nextnode;

  struct pim_secondary_addr *sec_addr;

  struct pim_interface *pim_ifp;

  struct interface *ifp;

  struct pim_instance *pim = p_ifp->pim;

  /* Trying to get the unicast address from the RPF interface first */

  for (ALL_LIST_ELEMENTS(p_ifp->sec_addr_list, node, nextnode,

             sec_addr)) {

    if (!is_ipv6_global_unicast(&sec_addr->addr.u.prefix6))

      continue;

    return sec_addr->addr.u.prefix6;

  }

  /* Loop through all the pim interface and try to return a global

   * unicast ipv6 address

   */

  FOR_ALL_INTERFACES (pim->vrf, ifp) {

    pim_ifp = ifp->info;

    if (!pim_ifp)

      continue;

    for (ALL_LIST_ELEMENTS(pim_ifp->sec_addr_list, node, nextnode,

               sec_addr)) {

      if (!is_ipv6_global_unicast(&sec_addr->addr.u.prefix6))

        continue;

      return sec_addr->addr.u.prefix6;

    }

  }

  zlog_warn("No global address found for use to send register message");

  return PIMADDR_ANY;

}

#endif

void pim_register_send(const uint8_t *buf, int buf_size, pim_addr src,

           struct pim_rpf *rpg, int null_register,

           struct pim_upstream *up)

{

  unsigned char buffer[10000];

  unsigned char *b1;

  struct pim_interface *pinfo;

  struct interface *ifp;

  if (PIM_DEBUG_PIM_REG) {

    zlog_debug("Sending %s %sRegister Packet to %pPA", up->sg_str,

         null_register ? "NULL " : "", &rpg->rpf_addr);

  }

  ifp = rpg->source_nexthop.interface;

  if (!ifp) {

    if (PIM_DEBUG_PIM_REG)

      zlog_debug("%s: No interface to transmit register on",

           __func__);

    return;

  }

  pinfo = (struct pim_interface *)ifp->info;

  if (!pinfo) {

    if (PIM_DEBUG_PIM_REG)

      zlog_debug(

        "%s: Interface: %s not configured for pim to transmit on!",

        __func__, ifp->name);

    return;

  }

  if (PIM_DEBUG_PIM_REG) {

    zlog_debug("%s: Sending %s %sRegister Packet to %pPA on %s",

         __func__, up->sg_str, null_register ? "NULL " : "",

         &rpg->rpf_addr, ifp->name);

  }

  memset(buffer, 0, 10000);

  b1 = buffer + PIM_MSG_HEADER_LEN;

  *b1 |= null_register << 6;

  b1 = buffer + PIM_MSG_REGISTER_LEN;

  memcpy(b1, (const unsigned char *)buf, buf_size);

#if PIM_IPV == 6

  /* While sending Register message to RP, we cannot use link-local

   * address therefore using unicast ipv6 address here, choosing it

   * from the RPF Interface

   */

  src = pim_register_get_unicast_v6_addr(pinfo);

#endif

  pim_msg_build_header(src, rpg->rpf_addr, buffer,

           buf_size + PIM_MSG_REGISTER_LEN,

           PIM_MSG_TYPE_REGISTER, false);

  if (!pinfo->pim_passive_enable)

    ++pinfo->pim_ifstat_reg_send;

  if (pim_msg_send(pinfo->pim->reg_sock, src, rpg->rpf_addr, buffer,

       buf_size + PIM_MSG_REGISTER_LEN, ifp)) {

    if (PIM_DEBUG_PIM_TRACE) {

      zlog_debug(

        "%s: could not send PIM register message on interface %s",

        __func__, ifp->name);

    }

    return;

  }

}

#if PIM_IPV == 4

void pim_null_register_send(struct pim_upstream *up)

{

  struct ip ip_hdr;

  struct pim_interface *pim_ifp;

  struct pim_rpf *rpg;

  pim_addr src;

  pim_ifp = up->rpf.source_nexthop.interface->info;

  if (!pim_ifp) {

    if (PIM_DEBUG_PIM_TRACE)

      zlog_debug(

        "%s: Cannot send null-register for %s no valid iif",

        __func__, up->sg_str);

    return;

  }

  rpg = RP(pim_ifp->pim, up->sg.grp);

  if (!rpg) {

    if (PIM_DEBUG_PIM_TRACE)

      zlog_debug(

        "%s: Cannot send null-register for %s no RPF to the RP",

        __func__, up->sg_str);

    return;

  }

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

  ip_hdr.ip_p = PIM_IP_PROTO_PIM;

  ip_hdr.ip_hl = 5;

  ip_hdr.ip_v = 4;

  ip_hdr.ip_src = up->sg.src;

  ip_hdr.ip_dst = up->sg.grp;

  ip_hdr.ip_len = htons(20);

  /* checksum is broken */

  src = pim_ifp->primary_address;

  if (PIM_UPSTREAM_FLAG_TEST_SRC_VXLAN_ORIG(up->flags)) {

    if (!pim_vxlan_get_register_src(pim_ifp->pim, up, &src)) {

      if (PIM_DEBUG_PIM_TRACE)

        zlog_debug(

          "%s: Cannot send null-register for %s vxlan-aa PIP unavailable",

          __func__, up->sg_str);

      return;

    }

  }

  pim_register_send((uint8_t *)&ip_hdr, sizeof(struct ip), src, rpg, 1,

        up);

}

#else

void pim_null_register_send(struct pim_upstream *up)

{

  struct ip6_hdr ip6_hdr;

  struct pim_msg_header pim_msg_header;

  struct pim_interface *pim_ifp;

  struct pim_rpf *rpg;

  pim_addr src;

  unsigned char buffer[sizeof(ip6_hdr) + sizeof(pim_msg_header)];

  struct ipv6_ph ph;

  pim_ifp = up->rpf.source_nexthop.interface->info;

  if (!pim_ifp) {

    if (PIM_DEBUG_PIM_TRACE)

      zlog_debug(

        "Cannot send null-register for %s no valid iif",

        up->sg_str);

    return;

  }

  rpg = RP(pim_ifp->pim, up->sg.grp);

  if (!rpg) {

    if (PIM_DEBUG_PIM_TRACE)

      zlog_debug(

        "Cannot send null-register for %s no RPF to the RP",

        up->sg_str);

    return;

  }

  memset(&ip6_hdr, 0, sizeof(ip6_hdr));

  ip6_hdr.ip6_nxt = PIM_IP_PROTO_PIM;

  ip6_hdr.ip6_plen = PIM_MSG_HEADER_LEN;

  ip6_hdr.ip6_vfc = 6 << 4;

  ip6_hdr.ip6_hlim = MAXTTL;

  ip6_hdr.ip6_src = up->sg.src;

  ip6_hdr.ip6_dst = up->sg.grp;

  memset(buffer, 0, (sizeof(ip6_hdr) + sizeof(pim_msg_header)));

  memcpy(buffer, &ip6_hdr, sizeof(ip6_hdr));

  pim_msg_header.ver = 0;

  pim_msg_header.type = 0;

  pim_msg_header.reserved = 0;

  pim_msg_header.checksum = 0;

  ph.src = up->sg.src;

  ph.dst = up->sg.grp;

  ph.ulpl = htonl(PIM_MSG_HEADER_LEN);

  ph.next_hdr = IPPROTO_PIM;

  pim_msg_header.checksum =

    in_cksum_with_ph6(&ph, &pim_msg_header, PIM_MSG_HEADER_LEN);

  memcpy(buffer + sizeof(ip6_hdr), &pim_msg_header, PIM_MSG_HEADER_LEN);

  src = pim_ifp->primary_address;

  pim_register_send((uint8_t *)buffer,

        sizeof(ip6_hdr) + PIM_MSG_HEADER_LEN, src, rpg, 1,

        up);

}

#endif

/*

 * 4.4.2 Receiving Register Messages at the RP

 *

 *   When an RP receives a Register message, the course of action is

 *  decided according to the following pseudocode:

 *

 *  packet_arrives_on_rp_tunnel( pkt ) {

 *      if( outer.dst is not one of my addresses ) {

 *          drop the packet silently.

 *          # Note: this may be a spoofing attempt

 *      }

 *      if( I_am_RP(G) AND outer.dst == RP(G) ) {

 *            sentRegisterStop = false;

 *            if ( register.borderbit == true ) {

 *                 if ( PMBR(S,G) == unknown ) {

 *                      PMBR(S,G) = outer.src

 *                 } else if ( outer.src != PMBR(S,G) ) {

 *                      send Register-Stop(S,G) to outer.src

 *                      drop the packet silently.

 *                 }

 *            }

 *            if ( SPTbit(S,G) OR

 *             ( SwitchToSptDesired(S,G) AND

 *               ( inherited_olist(S,G) == NULL ))) {

 *              send Register-Stop(S,G) to outer.src

 *              sentRegisterStop = true;

 *            }

 *            if ( SPTbit(S,G) OR SwitchToSptDesired(S,G) ) {

 *                 if ( sentRegisterStop == true ) {

 *                      set KeepaliveTimer(S,G) to RP_Keepalive_Period;

 *                 } else {

 *                      set KeepaliveTimer(S,G) to Keepalive_Period;

 *                 }

 *            }

 *            if( !SPTbit(S,G) AND ! pkt.NullRegisterBit ) {

 *                 decapsulate and forward the inner packet to

 *                 inherited_olist(S,G,rpt) # Note (+)

 *            }

 *      } else {

 *          send Register-Stop(S,G) to outer.src

 *          # Note (*)

 *      }

 *  }

 */

int pim_register_recv(struct interface *ifp, pim_addr dest_addr,

          pim_addr src_addr, uint8_t *tlv_buf, int tlv_buf_size)

{

  int sentRegisterStop = 0;

  const void *ip_hdr;

  pim_sgaddr sg;

  uint32_t *bits;

  int i_am_rp = 0;

  struct pim_interface *pim_ifp = ifp->info;

  struct pim_instance *pim = pim_ifp->pim;

  pim_addr rp_addr;

  struct pim_rpf *rpg;

  if (pim_ifp->pim_passive_enable) {

    if (PIM_DEBUG_PIM_PACKETS)

      zlog_debug(

        "skip receiving PIM message on passive interface %s",

        ifp->name);

    return 0;

  }

#define PIM_MSG_REGISTER_BIT_RESERVED_LEN 4

  if (tlv_buf_size

      < (int)(PIM_MSG_REGISTER_BIT_RESERVED_LEN + sizeof(struct ip))) {

    return 0;

  }

  ip_hdr = (tlv_buf + PIM_MSG_REGISTER_BIT_RESERVED_LEN);

  if (!if_address_is_local(&dest_addr, PIM_AF, pim->vrf->vrf_id)) {

    if (PIM_DEBUG_PIM_REG)

      zlog_debug(

        "%s: Received Register message for destination address: %pPA that I do not own",

        __func__, &dest_addr);

    return 0;

  }

  ++pim_ifp->pim_ifstat_reg_recv;

  /*

   * Please note this is not drawn to get the correct bit/data size

   *

   * The entirety of the REGISTER packet looks like this:

   * -------------------------------------------------------------

   * | Ver  | Type | Reserved     |       Checksum               |

   * |-----------------------------------------------------------|

   * |B|N|     Reserved 2                                        |

   * |-----------------------------------------------------------|

   * | Encap  |                IP HDR                            |

   * | Mcast  |                                                  |

   * | Packet |--------------------------------------------------|

   * |        |               Mcast Data                         |

   * |        |                                                  |

   * ...

   *

   * tlv_buf when received from the caller points at the B bit

   * We need to know the inner source and dest

   */

  bits = (uint32_t *)tlv_buf;

  /*

   * tlv_buf points to the start of the |B|N|... Reserved

   * Line above.  So we need to add 4 bytes to get to the

   * start of the actual Encapsulated data.

   */

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

  sg = pim_sgaddr_from_iphdr(ip_hdr);

#if PIM_IPV == 6

  /*

   * According to RFC section 4.9.3, If Dummy PIM Header is included

   * in NULL Register as a payload there would be two PIM headers.

   * The inner PIM Header's checksum field should also be validated

   * in addition to the outer PIM Header's checksum. Validation of

   * inner PIM header checksum is done here.

   */

  if ((*bits & PIM_REGISTER_NR_BIT) &&

      ((tlv_buf_size - PIM_MSG_REGISTER_BIT_RESERVED_LEN) >

       (int)sizeof(struct ip6_hdr))) {

    uint16_t computed_checksum;

    uint16_t received_checksum;

    struct ipv6_ph ph;

    struct pim_msg_header *header;

    header = (struct pim_msg_header

          *)(tlv_buf +

             PIM_MSG_REGISTER_BIT_RESERVED_LEN +

             sizeof(struct ip6_hdr));

    ph.src = sg.src;

    ph.dst = sg.grp;

    ph.ulpl = htonl(PIM_MSG_HEADER_LEN);

    ph.next_hdr = IPPROTO_PIM;

    received_checksum = header->checksum;

    header->checksum = 0;

    computed_checksum = in_cksum_with_ph6(

      &ph, header, htonl(PIM_MSG_HEADER_LEN));

    if (computed_checksum != received_checksum) {

      if (PIM_DEBUG_PIM_PACKETS)

        zlog_debug(

          "Ignoring Null Register message%pSG from %pPA due to bad checksum in Encapsulated dummy PIM header",

          &sg, &src_addr);

      return 0;

    }

  }

#endif

  i_am_rp = I_am_RP(pim, sg.grp);

  if (PIM_DEBUG_PIM_REG)

    zlog_debug(

      "Received Register message%pSG from %pPA on %s, rp: %d",

      &sg, &src_addr, ifp->name, i_am_rp);

  if (pim_is_grp_ssm(pim_ifp->pim, sg.grp)) {

    if (pim_addr_is_any(sg.src)) {

      zlog_warn(

        "%s: Received Register message for Group(%pPA) is now in SSM, dropping the packet",

        __func__, &sg.grp);

      /* Drop Packet Silently */

      return 0;

    }

  }

  rpg = RP(pim, sg.grp);

  if (!rpg) {

    zlog_warn("%s: Received Register Message %pSG from %pPA on %s where the RP could not be looked up",

        __func__, &sg, &src_addr, ifp->name);

    return 0;

  }

  rp_addr = rpg->rpf_addr;

  if (i_am_rp && (!pim_addr_cmp(dest_addr, rp_addr))) {

    sentRegisterStop = 0;

    if (pim->register_plist) {

      struct prefix_list *plist;

      struct prefix src;

      plist = prefix_list_lookup(PIM_AFI,

               pim->register_plist);

      pim_addr_to_prefix(&src, sg.src);

      if (prefix_list_apply_ext(plist, NULL, &src, true) ==

          PREFIX_DENY) {

        pim_register_stop_send(ifp, &sg, dest_addr,

                   src_addr);

        if (PIM_DEBUG_PIM_PACKETS)

          zlog_debug(

            "%s: Sending register-stop to %pPA for %pSG due to prefix-list denial, dropping packet",

            __func__, &src_addr, &sg);

        return 0;

      }

    }

    if (*bits & PIM_REGISTER_BORDER_BIT) {

      if (PIM_DEBUG_PIM_PACKETS)

        zlog_debug(

          "%s: Received Register message with Border bit set, ignoring",

          __func__);

        /* Drop Packet Silently */

      return 0;

    }

    struct pim_upstream *upstream = pim_upstream_find(pim, &sg);

    /*

     * If we don't have a place to send ignore the packet

     */

    if (!upstream) {

      upstream = pim_upstream_add(

        pim, &sg, ifp,

        PIM_UPSTREAM_FLAG_MASK_SRC_STREAM, __func__,

        NULL);

      if (!upstream) {

        zlog_warn("Failure to create upstream state");

        return 1;

      }

      upstream->upstream_register = src_addr;

    } else {

      /*

       * If the FHR has set a very very fast register timer

       * there exists a possibility that the incoming NULL

       * register

       * is happening before we set the spt bit.  If so

       * Do a quick check to update the counters and

       * then set the spt bit as appropriate

       */

      if (upstream->sptbit != PIM_UPSTREAM_SPTBIT_TRUE) {

        pim_mroute_update_counters(

          upstream->channel_oil);

        /*

         * Have we seen packets?

         */

        if (upstream->channel_oil->cc.oldpktcnt

            < upstream->channel_oil->cc.pktcnt)

          pim_upstream_set_sptbit(

            upstream,

            upstream->rpf.source_nexthop

              .interface);

      }

    }

    if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)

        || ((SwitchToSptDesiredOnRp(pim, &sg))

      && pim_upstream_inherited_olist(pim, upstream) == 0)) {

      pim_register_stop_send(ifp, &sg, dest_addr, src_addr);

      sentRegisterStop = 1;

    } else {

      if (PIM_DEBUG_PIM_REG)

        zlog_debug("(%s) sptbit: %d", upstream->sg_str,

             upstream->sptbit);

    }

    if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)

        || (SwitchToSptDesiredOnRp(pim, &sg))) {

      if (sentRegisterStop) {

        pim_upstream_keep_alive_timer_start(

          upstream, pim->rp_keep_alive_time);

      } else {

        pim_upstream_keep_alive_timer_start(

          upstream, pim->keep_alive_time);

      }

    }

    if (!(upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)

        && !(*bits & PIM_REGISTER_NR_BIT)) {

      // decapsulate and forward the iner packet to

      // inherited_olist(S,G,rpt)

      // This is taken care of by the kernel for us

    }

    pim_upstream_msdp_reg_timer_start(upstream);

  } else {

    if (PIM_DEBUG_PIM_REG) {

      if (!i_am_rp)

        zlog_debug("Received Register packet for %pSG, Rejecting packet because I am not the RP configured for group",

             &sg);

      else

        zlog_debug("Received Register packet for %pSG, Rejecting packet because the dst ip address is not the actual RP",

             &sg);

    }

    pim_register_stop_send(ifp, &sg, dest_addr, src_addr);

  }

  return 0;

}

/*

 * This routine scan all upstream and update register state and remove pimreg

 * when couldreg becomes false.

 */

void pim_reg_del_on_couldreg_fail(struct interface *ifp)

{

  struct pim_interface *pim_ifp = ifp->info;

  struct pim_instance *pim;

  struct pim_upstream *up;

  if (!pim_ifp)

    return;

  pim = pim_ifp->pim;

  frr_each (rb_pim_upstream, &pim->upstream_head, up) {

    if (ifp != up->rpf.source_nexthop.interface)

      continue;

    if (!pim_upstream_could_register(up)

        && (up->reg_state != PIM_REG_NOINFO)) {

      pim_channel_del_oif(up->channel_oil, pim->regiface,

              PIM_OIF_FLAG_PROTO_PIM, __func__);

      EVENT_OFF(up->t_rs_timer);

      up->reg_state = PIM_REG_NOINFO;

    }

  }

}