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path: root/pimd/pim_rp.c
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/*
 * PIM for Quagga
 * Copyright (C) 2015 Cumulus Networks, Inc.
 * Donald Sharp
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */
#include <zebra.h>

#include "lib/json.h"
#include "log.h"
#include "network.h"
#include "if.h"
#include "linklist.h"
#include "prefix.h"
#include "memory.h"
#include "vty.h"
#include "vrf.h"
#include "plist.h"
#include "nexthop.h"

#include "pimd.h"
#include "pim_vty.h"
#include "pim_str.h"
#include "pim_iface.h"
#include "pim_rp.h"
#include "pim_str.h"
#include "pim_rpf.h"
#include "pim_sock.h"
#include "pim_memory.h"
#include "pim_iface.h"
#include "pim_msdp.h"
#include "pim_nht.h"


static struct list *qpim_rp_list = NULL;
static struct rp_info *tail = NULL;

static void
pim_rp_info_free (struct rp_info *rp_info)
{
  XFREE (MTYPE_PIM_RP, rp_info);
}

int
pim_rp_list_cmp (void *v1, void *v2)
{
  struct rp_info *rp1 = (struct rp_info *)v1;
  struct rp_info *rp2 = (struct rp_info *)v2;

  /*
   * Sort by RP IP address
   */
  if (rp1->rp.rpf_addr.u.prefix4.s_addr < rp2->rp.rpf_addr.u.prefix4.s_addr)
    return -1;

  if (rp1->rp.rpf_addr.u.prefix4.s_addr > rp2->rp.rpf_addr.u.prefix4.s_addr)
    return 1;

  /*
   * Sort by group IP address
   */
  if (rp1->group.u.prefix4.s_addr < rp2->group.u.prefix4.s_addr)
    return -1;

  if (rp1->group.u.prefix4.s_addr > rp2->group.u.prefix4.s_addr)
    return 1;

  return 0;
}

void
pim_rp_init (void)
{
  struct rp_info *rp_info;

  qpim_rp_list = list_new ();
  qpim_rp_list->del = (void (*)(void *))pim_rp_info_free;
  qpim_rp_list->cmp = pim_rp_list_cmp;

  rp_info = XCALLOC (MTYPE_PIM_RP, sizeof (*rp_info));

  if (!rp_info)
    return;

  str2prefix ("224.0.0.0/4", &rp_info->group);
  rp_info->group.family = AF_INET;
  rp_info->rp.rpf_addr.family = AF_INET;
  rp_info->rp.rpf_addr.u.prefix4.s_addr = INADDR_NONE;
  tail = rp_info;

  listnode_add (qpim_rp_list, rp_info);
}

void
pim_rp_free (void)
{
  if (qpim_rp_list)
    list_delete (qpim_rp_list);
  qpim_rp_list = NULL;
}

/*
 * Given an RP's prefix-list, return the RP's rp_info for that prefix-list
 */
static struct rp_info *
pim_rp_find_prefix_list (struct in_addr rp, const char *plist)
{
  struct listnode *node;
  struct rp_info *rp_info;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (rp.s_addr == rp_info->rp.rpf_addr.u.prefix4.s_addr &&
          rp_info->plist && strcmp(rp_info->plist, plist) == 0)
        {
          return rp_info;
        }
    }

  return NULL;
}

/*
 * Return true if plist is used by any rp_info
 */
static int
pim_rp_prefix_list_used (const char *plist)
{
  struct listnode *node;
  struct rp_info *rp_info;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (rp_info->plist && strcmp(rp_info->plist, plist) == 0)
        {
          return 1;
        }
    }

  return 0;
}

/*
 * Given an RP's address, return the RP's rp_info that is an exact match for 'group'
 */
static struct rp_info *
pim_rp_find_exact (struct in_addr rp, struct prefix *group)
{
  struct listnode *node;
  struct rp_info *rp_info;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (rp.s_addr == rp_info->rp.rpf_addr.u.prefix4.s_addr &&
	  prefix_same (&rp_info->group, group))
       return rp_info;
    }

  return NULL;
}

/*
 * Given a group, return the rp_info for that group
 */
static struct rp_info *
pim_rp_find_match_group (struct prefix *group)
{
  struct listnode *node;
  struct rp_info *rp_info;
  struct prefix_list *plist;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (rp_info->plist)
        {
          plist = prefix_list_lookup (AFI_IP, rp_info->plist);

          if (plist && prefix_list_apply (plist, group) == PREFIX_PERMIT)
            return rp_info;
        }
      else
        {
          if (prefix_match (&rp_info->group, group))
            return rp_info;
        }
    }

  return NULL;
}

/*
 * When the user makes "ip pim rp" configuration changes or if they change the
 * prefix-list(s) used by these statements we must tickle the upstream state
 * for each group to make them re-lookup who their RP should be.
 *
 * This is a placeholder function for now.
 */
static void
pim_rp_refresh_group_to_rp_mapping()
{
  pim_msdp_i_am_rp_changed();
}

void
pim_rp_prefix_list_update (struct prefix_list *plist)
{
  struct listnode *node;
  struct rp_info *rp_info;
  int refresh_needed = 0;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (rp_info->plist && strcmp(rp_info->plist, prefix_list_name (plist)) == 0)
        {
          refresh_needed = 1;
          break;
        }
    }

  if (refresh_needed)
    pim_rp_refresh_group_to_rp_mapping();
}

static int
pim_rp_check_interface_addrs(struct rp_info *rp_info,
                             struct pim_interface *pim_ifp)
{
  struct listnode *node;
  struct pim_secondary_addr *sec_addr;

  if (pim_ifp->primary_address.s_addr == rp_info->rp.rpf_addr.u.prefix4.s_addr)
    return 1;

  if (!pim_ifp->sec_addr_list) {
    return 0;
  }

  for (ALL_LIST_ELEMENTS_RO(pim_ifp->sec_addr_list, node, sec_addr)) {
    if (prefix_same(&sec_addr->addr, &rp_info->rp.rpf_addr)) {
      return 1;
    }
  }

  return 0;
}

static void
pim_rp_check_interfaces (struct rp_info *rp_info)
{
  struct listnode *node;
  struct interface *ifp;

  rp_info->i_am_rp = 0;
  for (ALL_LIST_ELEMENTS_RO (vrf_iflist (VRF_DEFAULT), node, ifp))
    {
      struct pim_interface *pim_ifp = ifp->info;

      if (!pim_ifp)
        continue;

      if (pim_rp_check_interface_addrs(rp_info, pim_ifp)) {
        rp_info->i_am_rp = 1;
      }
    }
}

int
pim_rp_new (const char *rp, const char *group_range, const char *plist)
{
  int result = 0;
  struct rp_info *rp_info;
  struct rp_info *rp_all;
  struct prefix group_all;
  struct listnode *node, *nnode;
  struct rp_info *tmp_rp_info;
  char buffer[BUFSIZ];
  struct prefix nht_p;
  struct pim_nexthop_cache pnc;

  rp_info = XCALLOC (MTYPE_PIM_RP, sizeof (*rp_info));
  if (!rp_info)
    return PIM_MALLOC_FAIL;

  if (group_range == NULL)
    result = str2prefix ("224.0.0.0/4", &rp_info->group);
  else
    result = str2prefix (group_range, &rp_info->group);

  if (!result)
    {
      XFREE (MTYPE_PIM_RP, rp_info);
      return PIM_GROUP_BAD_ADDRESS;
    }

  rp_info->rp.rpf_addr.family = AF_INET;
  result = inet_pton (rp_info->rp.rpf_addr.family, rp, &rp_info->rp.rpf_addr.u.prefix4);

  if (result <= 0)
    {
      XFREE (MTYPE_PIM_RP, rp_info);
      return PIM_RP_BAD_ADDRESS;
    }

  if (plist)
    {
      /*
       * Return if the prefix-list is already configured for this RP
       */
      if (pim_rp_find_prefix_list (rp_info->rp.rpf_addr.u.prefix4, plist))
        {
          XFREE (MTYPE_PIM_RP, rp_info);
          return PIM_SUCCESS;
        }

      /*
       * Barf if the prefix-list is already configured for an RP
       */
      if (pim_rp_prefix_list_used (plist))
        {
          XFREE (MTYPE_PIM_RP, rp_info);
          return PIM_RP_PFXLIST_IN_USE;
        }

      /*
       * Free any existing rp_info entries for this RP
       */
      for (ALL_LIST_ELEMENTS (qpim_rp_list, node, nnode, tmp_rp_info))
        {
          if (rp_info->rp.rpf_addr.u.prefix4.s_addr == tmp_rp_info->rp.rpf_addr.u.prefix4.s_addr)
            {
              if (tmp_rp_info->plist)
                pim_rp_del (rp, NULL, tmp_rp_info->plist);
              else
                pim_rp_del (rp, prefix2str(&tmp_rp_info->group, buffer, BUFSIZ), NULL);
            }
        }

      rp_info->plist = XSTRDUP(MTYPE_PIM_FILTER_NAME, plist);
    }
  else
    {
      str2prefix ("224.0.0.0/4", &group_all);
      rp_all = pim_rp_find_match_group(&group_all);

      /*
       * Barf if group is a non-multicast subnet
       */
      if (! prefix_match (&rp_all->group, &rp_info->group))
        {
          XFREE (MTYPE_PIM_RP, rp_info);
          return PIM_GROUP_BAD_ADDRESS;
        }

      /*
       * Remove any prefix-list rp_info entries for this RP
       */
      for (ALL_LIST_ELEMENTS (qpim_rp_list, node, nnode, tmp_rp_info))
        {
          if (tmp_rp_info->plist &&
              rp_info->rp.rpf_addr.u.prefix4.s_addr == tmp_rp_info->rp.rpf_addr.u.prefix4.s_addr)
            {
              pim_rp_del (rp, NULL, tmp_rp_info->plist);
            }
        }

      /*
       * Take over the 224.0.0.0/4 group if the rp is INADDR_NONE
       */
      if (prefix_same (&rp_all->group, &rp_info->group) &&
          pim_rpf_addr_is_inaddr_none (&rp_all->rp))
        {
          rp_all->rp.rpf_addr = rp_info->rp.rpf_addr;
          XFREE (MTYPE_PIM_RP, rp_info);

          /* Register addr with Zebra NHT */
          nht_p.family = AF_INET;
          nht_p.prefixlen = IPV4_MAX_BITLEN;
          nht_p.u.prefix4 = rp_all->rp.rpf_addr.u.prefix4;      //RP address
          if (PIM_DEBUG_PIM_TRACE)
            {
              char buf[PREFIX2STR_BUFFER];
              char buf1[PREFIX2STR_BUFFER];
              prefix2str (&nht_p, buf, sizeof (buf));
              prefix2str (&rp_all->group, buf1, sizeof (buf1));
              zlog_debug ("%s: NHT Register rp_all addr %s grp %s ",
                          __PRETTY_FUNCTION__, buf, buf1);
            }
          memset (&pnc, 0, sizeof (struct pim_nexthop_cache));
          if ((pim_find_or_track_nexthop (&nht_p, NULL, rp_all, &pnc)) == 1)
            {
              //Compute PIM RPF using Cached nexthop
              if ((pim_ecmp_nexthop_search (&pnc, &rp_all->rp.source_nexthop,
                                       &nht_p, &rp_all->group, 1)) != 0)
                return PIM_RP_NO_PATH;
            }
          else
            {
              if (pim_nexthop_lookup (&rp_all->rp.source_nexthop, rp_all->rp.rpf_addr.u.prefix4, 1) != 0)
                return PIM_RP_NO_PATH;
            }
          pim_rp_check_interfaces (rp_all);
          pim_rp_refresh_group_to_rp_mapping ();
          return PIM_SUCCESS;
        }

      /*
       * Return if the group is already configured for this RP
       */
      if (pim_rp_find_exact (rp_info->rp.rpf_addr.u.prefix4, &rp_info->group))
        {
          XFREE (MTYPE_PIM_RP, rp_info);
          return PIM_SUCCESS;
        }

      /*
       * Barf if this group is already covered by some other RP
       */
      tmp_rp_info = pim_rp_find_match_group (&rp_info->group);

      if (tmp_rp_info)
        {
          if (tmp_rp_info->plist)
            {
                XFREE (MTYPE_PIM_RP, rp_info);
                return PIM_GROUP_PFXLIST_OVERLAP;
            }
          else
            {
              /*
               * If the only RP that covers this group is an RP configured for
               * 224.0.0.0/4 that is fine, ignore that one.  For all others
               * though we must return PIM_GROUP_OVERLAP
               */
              if (! prefix_same (&group_all, &tmp_rp_info->group))
                {
                  XFREE (MTYPE_PIM_RP, rp_info);
                  return PIM_GROUP_OVERLAP;
                }
            }
        }
    }

  listnode_add_sort (qpim_rp_list, rp_info);

  /* Register addr with Zebra NHT */
  nht_p.family = AF_INET;
  nht_p.prefixlen = IPV4_MAX_BITLEN;
  nht_p.u.prefix4 = rp_info->rp.rpf_addr.u.prefix4;
  if (PIM_DEBUG_PIM_TRACE)
    {
      char buf[PREFIX2STR_BUFFER];
      char buf1[PREFIX2STR_BUFFER];
      prefix2str (&nht_p, buf, sizeof (buf));
      prefix2str (&rp_info->group, buf1, sizeof (buf1));
      zlog_debug ("%s: NHT Register RP addr %s grp %s with Zebra ",
                  __PRETTY_FUNCTION__, buf, buf1);
    }

  memset (&pnc, 0, sizeof (struct pim_nexthop_cache));
  if ((pim_find_or_track_nexthop (&nht_p, NULL, rp_info, &pnc)) == 1)
    {
      //Compute PIM RPF using Cached nexthop
      if (pim_ecmp_nexthop_search (&pnc, &rp_info->rp.source_nexthop,
                               &nht_p, &rp_info->group, 1) != 0)
        return PIM_RP_NO_PATH;
    }
  else
    {
      if (pim_nexthop_lookup (&rp_info->rp.source_nexthop, rp_info->rp.rpf_addr.u.prefix4, 1) != 0)
        return PIM_RP_NO_PATH;
    }

  pim_rp_check_interfaces (rp_info);
  pim_rp_refresh_group_to_rp_mapping ();
  return PIM_SUCCESS;
}

int
pim_rp_del (const char *rp, const char *group_range, const char *plist)
{
  struct prefix group;
  struct in_addr rp_addr;
  struct prefix g_all;
  struct rp_info *rp_info;
  struct rp_info *rp_all;
  int result;
  struct prefix nht_p;

  if (group_range == NULL)
    result = str2prefix ("224.0.0.0/4", &group);
  else
    result = str2prefix (group_range, &group);

  if (!result)
    return PIM_GROUP_BAD_ADDRESS;

  result = inet_pton (AF_INET, rp, &rp_addr);
  if (result <= 0)
    return PIM_RP_BAD_ADDRESS;

  if (plist)
    rp_info = pim_rp_find_prefix_list (rp_addr, plist);
  else
    rp_info = pim_rp_find_exact (rp_addr, &group);

  if (!rp_info)
    return PIM_RP_NOT_FOUND;

  if (rp_info->plist)
    {
      XFREE(MTYPE_PIM_FILTER_NAME, rp_info->plist);
      rp_info->plist = NULL;
    }

  /* Deregister addr with Zebra NHT */
  nht_p.family = AF_INET;
  nht_p.prefixlen = IPV4_MAX_BITLEN;
  nht_p.u.prefix4 = rp_info->rp.rpf_addr.u.prefix4;
  if (PIM_DEBUG_PIM_TRACE)
    {
      char buf[PREFIX2STR_BUFFER];
      prefix2str (&nht_p, buf, sizeof (buf));
      zlog_debug ("%s: Deregister RP addr %s with Zebra ", __PRETTY_FUNCTION__,
                  buf);
    }
  pim_delete_tracked_nexthop (&nht_p, NULL, rp_info);

  str2prefix ("224.0.0.0/4", &g_all);
  rp_all = pim_rp_find_match_group (&g_all);

  if (rp_all == rp_info)
    {
      rp_all->rp.rpf_addr.family = AF_INET;
      rp_all->rp.rpf_addr.u.prefix4.s_addr = INADDR_NONE;
      rp_all->i_am_rp = 0;
      return PIM_SUCCESS;
    }

  listnode_delete (qpim_rp_list, rp_info);
  pim_rp_refresh_group_to_rp_mapping ();
  return PIM_SUCCESS;
}

int
pim_rp_setup (void)
{
  struct listnode *node;
  struct rp_info *rp_info;
  int ret = 0;
  struct prefix nht_p;
  struct pim_nexthop_cache pnc;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (rp_info->rp.rpf_addr.u.prefix4.s_addr == INADDR_NONE)
        continue;

      nht_p.family = AF_INET;
      nht_p.prefixlen = IPV4_MAX_BITLEN;
      nht_p.u.prefix4 = rp_info->rp.rpf_addr.u.prefix4;
      memset (&pnc, 0, sizeof (struct pim_nexthop_cache));
      if ((pim_find_or_track_nexthop (&nht_p, NULL, rp_info, &pnc)) == 1)
        {
          //Compute PIM RPF using Cached nexthop
          if ((pim_ecmp_nexthop_search (&pnc, &rp_info->rp.source_nexthop,
                                   &nht_p, &rp_info->group, 1)) != 0)
            ret++;
        }
      else
        {
          if (PIM_DEBUG_ZEBRA)
            {
              char buf[PREFIX2STR_BUFFER];
              prefix2str (&nht_p, buf, sizeof (buf));
              zlog_debug ("%s: NHT Local Nexthop not found for RP %s ",
                          __PRETTY_FUNCTION__, buf);
            }
          if (pim_nexthop_lookup (&rp_info->rp.source_nexthop, rp_info->rp.rpf_addr.u.prefix4, 1) != 0)
            {
              if (PIM_DEBUG_PIM_TRACE)
                zlog_debug ("Unable to lookup nexthop for rp specified");
              ret++;
            }
        }
    }

  if (ret)
    return 0;

  return 1;
}

/*
 * Checks to see if we should elect ourself the actual RP when new if
 * addresses are added against an interface.
 */
void
pim_rp_check_on_if_add(struct pim_interface *pim_ifp)
{
  struct listnode *node;
  struct rp_info *rp_info;
  bool i_am_rp_changed = false;

  if (qpim_rp_list == NULL)
    return;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info)) {
    if (pim_rpf_addr_is_inaddr_none (&rp_info->rp))
      continue;

    /* if i_am_rp is already set nothing to be done (adding new addresses
     * is not going to make a difference). */
    if (rp_info->i_am_rp) {
      continue;
    }

    if (pim_rp_check_interface_addrs(rp_info, pim_ifp)) {
      i_am_rp_changed = true;
      rp_info->i_am_rp = 1;
      if (PIM_DEBUG_ZEBRA) {
        char rp[PREFIX_STRLEN];
        pim_addr_dump("<rp?>", &rp_info->rp.rpf_addr, rp, sizeof(rp));
        zlog_debug("%s: %s: i am rp", __func__, rp);
      }
    }
  }

  if (i_am_rp_changed) {
    pim_msdp_i_am_rp_changed();
  }
}

/* up-optimized re-evaluation of "i_am_rp". this is used when ifaddresses
 * are removed. Removing numbers is an uncommon event in an active network
 * so I have made no attempt to optimize it. */
void
pim_i_am_rp_re_evaluate(void)
{
  struct listnode *node;
  struct rp_info *rp_info;
  bool i_am_rp_changed = false;
  int old_i_am_rp;

  if (qpim_rp_list == NULL)
    return;

  for (ALL_LIST_ELEMENTS_RO(qpim_rp_list, node, rp_info)) {
    if (pim_rpf_addr_is_inaddr_none(&rp_info->rp))
      continue;

    old_i_am_rp = rp_info->i_am_rp;
    pim_rp_check_interfaces(rp_info);

    if (old_i_am_rp != rp_info->i_am_rp) {
      i_am_rp_changed = true;
      if (PIM_DEBUG_ZEBRA) {
        char rp[PREFIX_STRLEN];
        pim_addr_dump("<rp?>", &rp_info->rp.rpf_addr, rp, sizeof(rp));
        if (rp_info->i_am_rp) {
          zlog_debug("%s: %s: i am rp", __func__, rp);
        } else {
          zlog_debug("%s: %s: i am no longer rp", __func__, rp);
        }
      }
    }
  }

  if (i_am_rp_changed) {
    pim_msdp_i_am_rp_changed();
  }
}

/*
 * I_am_RP(G) is true if the group-to-RP mapping indicates that
 * this router is the RP for the group.
 *
 * Since we only have static RP, all groups are part of this RP
 */
int
pim_rp_i_am_rp (struct in_addr group)
{
  struct prefix g;
  struct rp_info *rp_info;

  memset (&g, 0, sizeof (g));
  g.family = AF_INET;
  g.prefixlen = 32;
  g.u.prefix4 = group;

  rp_info = pim_rp_find_match_group (&g);

  if (rp_info)
    return rp_info->i_am_rp;

  return 0;
}

/*
 * RP(G)
 *
 * Return the RP that the Group belongs too.
 */
struct pim_rpf *
pim_rp_g (struct in_addr group)
{
  struct prefix g;
  struct rp_info *rp_info;

  memset (&g, 0, sizeof (g));
  g.family = AF_INET;
  g.prefixlen = 32;
  g.u.prefix4 = group;

  rp_info = pim_rp_find_match_group (&g);

  if (rp_info)
    {
      struct prefix nht_p;
      struct pim_nexthop_cache pnc;
      /* Register addr with Zebra NHT */
      nht_p.family = AF_INET;
      nht_p.prefixlen = IPV4_MAX_BITLEN;
      nht_p.u.prefix4 = rp_info->rp.rpf_addr.u.prefix4;
      if (PIM_DEBUG_PIM_TRACE)
        {
          char buf[PREFIX2STR_BUFFER];
          char buf1[PREFIX2STR_BUFFER];
          prefix2str (&nht_p, buf, sizeof (buf));
          prefix2str (&rp_info->group, buf1, sizeof (buf1));
          zlog_debug ("%s: NHT Register RP addr %s grp %s with Zebra",
                      __PRETTY_FUNCTION__, buf, buf1);
        }
      memset (&pnc, 0, sizeof (struct pim_nexthop_cache));
      if ((pim_find_or_track_nexthop (&nht_p, NULL, rp_info, &pnc)) == 1)
        {
          //Compute PIM RPF using Cached nexthop
          pim_ecmp_nexthop_search (&pnc, &rp_info->rp.source_nexthop,
                                   &nht_p, &rp_info->group, 1);
        }
      else
        {
          if (PIM_DEBUG_ZEBRA)
            {
              char buf[PREFIX2STR_BUFFER];
              char buf1[PREFIX2STR_BUFFER];
              prefix2str (&nht_p, buf, sizeof (buf));
              prefix2str (&g, buf1, sizeof (buf1));
              zlog_debug ("%s: Nexthop cache not found for RP %s grp %s register with Zebra",
                          __PRETTY_FUNCTION__, buf, buf1);
            }
          pim_rpf_set_refresh_time ();
          pim_nexthop_lookup (&rp_info->rp.source_nexthop, rp_info->rp.rpf_addr.u.prefix4, 1);
        }
      return (&rp_info->rp);
    }

  // About to Go Down
  return NULL;
}

/*
 * Set the upstream IP address we want to talk to based upon
 * the rp configured and the source address
 *
 * If we have don't have a RP configured and the source address is *
 * then return failure.
 *
 */
int
pim_rp_set_upstream_addr (struct in_addr *up, struct in_addr source, struct in_addr group)
{
  struct rp_info *rp_info;
  struct prefix g;

  memset (&g, 0, sizeof (g));
  g.family = AF_INET;
  g.prefixlen = 32;
  g.u.prefix4 = group;

  rp_info = pim_rp_find_match_group (&g);

  if ((pim_rpf_addr_is_inaddr_none (&rp_info->rp)) && (source.s_addr == INADDR_ANY))
    {
      if (PIM_DEBUG_PIM_TRACE)
	zlog_debug("%s: Received a (*,G) with no RP configured", __PRETTY_FUNCTION__);
      return 0;
    }

  *up = (source.s_addr == INADDR_ANY) ? rp_info->rp.rpf_addr.u.prefix4 : source;

  return 1;
}

int
pim_rp_config_write (struct vty *vty)
{
  struct listnode *node;
  struct rp_info *rp_info;
  char rp_buffer[32];
  char group_buffer[32];
  int count = 0;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (pim_rpf_addr_is_inaddr_none (&rp_info->rp))
        continue;

      if (rp_info->plist)
        vty_out(vty, "ip pim rp %s prefix-list %s%s",
                inet_ntop(AF_INET, &rp_info->rp.rpf_addr.u.prefix4, rp_buffer, 32),
                rp_info->plist, VTY_NEWLINE);
      else
        vty_out(vty, "ip pim rp %s %s%s",
                inet_ntop(AF_INET, &rp_info->rp.rpf_addr.u.prefix4, rp_buffer, 32),
                prefix2str(&rp_info->group, group_buffer, 32), VTY_NEWLINE);
      count++;
    }

  return count;
}

int
pim_rp_check_is_my_ip_address (struct in_addr group, struct in_addr dest_addr)
{
  struct rp_info *rp_info;
  struct prefix g;

  memset (&g, 0, sizeof (g));
  g.family = AF_INET;
  g.prefixlen = 32;
  g.u.prefix4 = group;

  rp_info = pim_rp_find_match_group (&g);
  /*
   * See if we can short-cut some?
   * This might not make sense if we ever leave a static RP
   * type of configuration.
   * Note - Premature optimization might bite our patooeys' here.
   */
  if (I_am_RP(group))
    {
     if (dest_addr.s_addr == rp_info->rp.rpf_addr.u.prefix4.s_addr)
       return 1;
    }

  if (if_lookup_exact_address (&dest_addr, AF_INET, VRF_DEFAULT))
    return 1;

  return 0;
}

void
pim_rp_show_information (struct vty *vty, u_char uj)
{
  struct rp_info *rp_info;
  struct rp_info *prev_rp_info = NULL;
  struct listnode *node;

  json_object *json = NULL;
  json_object *json_rp_rows = NULL;
  json_object *json_row = NULL;

  if (uj)
    json = json_object_new_object();
  else
    vty_out (vty, "RP address       group/prefix-list   OIF         I am RP%s", VTY_NEWLINE);

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (!pim_rpf_addr_is_inaddr_none (&rp_info->rp))
        {
          char buf[48];

          if (uj)
            {
              /*
               * If we have moved on to a new RP then add the entry for the previous RP
               */
              if (prev_rp_info &&
                  prev_rp_info->rp.rpf_addr.u.prefix4.s_addr != rp_info->rp.rpf_addr.u.prefix4.s_addr)
                {
                  json_object_object_add(json, inet_ntoa (prev_rp_info->rp.rpf_addr.u.prefix4), json_rp_rows);
                  json_rp_rows = NULL;
                }

              if (!json_rp_rows)
                  json_rp_rows = json_object_new_array();

              json_row = json_object_new_object();
	      if (rp_info->rp.source_nexthop.interface)
		json_object_string_add(json_row, "outboundInterface", rp_info->rp.source_nexthop.interface->name);

              if (rp_info->i_am_rp)
                json_object_boolean_true_add(json_row, "iAmRP");

              if (rp_info->plist)
                json_object_string_add(json_row, "prefixList", rp_info->plist);
              else
                json_object_string_add(json_row, "group", prefix2str(&rp_info->group, buf, 48));

              json_object_array_add(json_rp_rows, json_row);
            }
          else
            {
              vty_out (vty, "%-15s  ", inet_ntoa (rp_info->rp.rpf_addr.u.prefix4));

              if (rp_info->plist)
                vty_out (vty, "%-18s  ", rp_info->plist);
              else
                vty_out (vty, "%-18s  ", prefix2str(&rp_info->group, buf, 48));

	      if (rp_info->rp.source_nexthop.interface)
		vty_out (vty, "%-10s  ", rp_info->rp.source_nexthop.interface->name);
	      else
		vty_out (vty, "%-10s  ", "(Unknown)");

              if (rp_info->i_am_rp)
                vty_out (vty, "yes%s", VTY_NEWLINE);
              else
                vty_out (vty, "no%s", VTY_NEWLINE);
            }

          prev_rp_info = rp_info;
        }
    }

  if (uj) {
    if (prev_rp_info && json_rp_rows)
      json_object_object_add(json, inet_ntoa (prev_rp_info->rp.rpf_addr.u.prefix4), json_rp_rows);

    vty_out (vty, "%s%s", json_object_to_json_string_ext(json, JSON_C_TO_STRING_PRETTY), VTY_NEWLINE);
    json_object_free(json);
  }
}

void
pim_resolve_rp_nh (void)
{
  struct listnode *node = NULL;
  struct rp_info *rp_info = NULL;
  struct nexthop *nh_node = NULL;
  struct prefix nht_p;
  struct pim_nexthop_cache pnc;
  struct pim_neighbor *nbr = NULL;

  for (ALL_LIST_ELEMENTS_RO (qpim_rp_list, node, rp_info))
    {
      if (rp_info->rp.rpf_addr.u.prefix4.s_addr == INADDR_NONE)
        continue;

      nht_p.family = AF_INET;
      nht_p.prefixlen = IPV4_MAX_BITLEN;
      nht_p.u.prefix4 = rp_info->rp.rpf_addr.u.prefix4;
      memset (&pnc, 0, sizeof (struct pim_nexthop_cache));
      if ((pim_find_or_track_nexthop (&nht_p, NULL, rp_info, &pnc)) == 1)
        {
          for (nh_node = pnc.nexthop; nh_node; nh_node = nh_node->next)
            {
              if (nh_node->gate.ipv4.s_addr == 0)
                {
                  nbr = pim_neighbor_find_if (if_lookup_by_index
                                          (nh_node->ifindex, VRF_DEFAULT));
                  if (nbr)
                    {
                      nh_node->gate.ipv4 = nbr->source_addr;
                      if (PIM_DEBUG_TRACE)
                        {
                          char str[PREFIX_STRLEN];
                          char str1[INET_ADDRSTRLEN];
                          struct interface *ifp1 = if_lookup_by_index(nh_node->ifindex,
                                                                              VRF_DEFAULT);
                          pim_inet4_dump ("<nht_nbr?>", nbr->source_addr,
                                          str1, sizeof (str1));
                          pim_addr_dump ("<nht_addr?>", &nht_p, str,
                                         sizeof (str));
                          zlog_debug ("%s: addr %s new nexthop addr %s interface %s",
                             __PRETTY_FUNCTION__, str, str1,
                             ifp1->name);
                        }
                    }
                }
            }
        }
    }
}