mirror_frr/pimd/pim_jp_agg.c

/*
 * PIM for FRR - J/P Aggregation
 * Copyright (C) 2017 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 "linklist.h"
#include "log.h"
#include "vrf.h"
#include "if.h"

#include "pimd.h"
#include "pim_msg.h"
#include "pim_jp_agg.h"
#include "pim_join.h"
#include "pim_iface.h"

void
pim_jp_agg_group_list_free (struct pim_jp_agg_group *jag)
{
  list_delete(jag->sources);

  XFREE (MTYPE_PIM_JP_AGG_GROUP, jag);
}

static void
pim_jp_agg_src_free (struct pim_jp_sources *js)
{
  struct pim_upstream *up = js->up;

  /*
   * When we are being called here, we know
   * that the neighbor is going away start
   * the normal j/p timer so that it can
   * pick this shit back up when the
   * nbr comes back alive
   */
  if (up)
    join_timer_start(js->up);
  XFREE (MTYPE_PIM_JP_AGG_SOURCE, js);
}

int
pim_jp_agg_group_list_cmp (void *arg1, void *arg2)
{
  const struct pim_jp_agg_group *jag1 = (const struct pim_jp_agg_group *)arg1;
  const struct pim_jp_agg_group *jag2 = (const struct pim_jp_agg_group *)arg2;

  if (jag1->group.s_addr < jag2->group.s_addr)
    return -1;

  if (jag1->group.s_addr > jag2->group.s_addr)
    return 1;

  return 0;
}

static int
pim_jp_agg_src_cmp (void *arg1, void *arg2)
{
  const struct pim_jp_sources *js1 = (const struct pim_jp_sources *)arg1;
  const struct pim_jp_sources *js2 = (const struct pim_jp_sources *)arg2;

  if (js1->is_join && !js2->is_join)
    return -1;

  if (!js1->is_join && js2->is_join)
    return 1;

  if (js1->up->sg.src.s_addr < js2->up->sg.src.s_addr)
    return -1;

  if (js1->up->sg.src.s_addr > js2->up->sg.src.s_addr)
    return 1;

  return 0;
}

/*
 * This function is used by scan_oil to clear
 * the created jp_agg_group created when
 * figuring out where to send prunes
 * and joins.
 */
void
pim_jp_agg_clear_group (struct list *group)
{
  struct listnode *gnode, *gnnode;
  struct listnode *snode, *snnode;
  struct pim_jp_agg_group *jag;
  struct pim_jp_sources *js;

  for (ALL_LIST_ELEMENTS(group, gnode, gnnode, jag))
    {
      for (ALL_LIST_ELEMENTS(jag->sources, snode, snnode, js))
        {
          listnode_delete(jag->sources, js);
          js->up = NULL;
          XFREE(MTYPE_PIM_JP_AGG_SOURCE, js);
        }
      jag->sources = NULL;
      listnode_delete(group, jag);
      XFREE(MTYPE_PIM_JP_AGG_GROUP, jag);
    }
}

static struct pim_iface_upstream_switch *
pim_jp_agg_get_interface_upstream_switch_list (struct pim_rpf *rpf)
{
  struct pim_interface *pim_ifp = rpf->source_nexthop.interface->info;
  struct pim_iface_upstream_switch *pius;
  struct listnode *node, *nnode;

  for (ALL_LIST_ELEMENTS(pim_ifp->upstream_switch_list, node, nnode, pius))
    {
      if (pius->address.s_addr == rpf->rpf_addr.u.prefix4.s_addr)
        break;
    }

  if (!pius)
    {
      pius = XCALLOC(MTYPE_PIM_JP_AGG_GROUP, sizeof (struct pim_iface_upstream_switch));
      pius->address.s_addr = rpf->rpf_addr.u.prefix4.s_addr;
      pius->us = list_new();
      listnode_add_sort (pim_ifp->upstream_switch_list, pius);
    }

  return pius;
}

void
pim_jp_agg_remove_group (struct list *group, struct pim_upstream *up)
{
  struct listnode *node, *nnode;
  struct pim_jp_agg_group *jag = NULL;
  struct pim_jp_sources *js = NULL;

  for (ALL_LIST_ELEMENTS(group, node, nnode, jag))
    {
      if (jag->group.s_addr == up->sg.grp.s_addr)
        break;
    }

  if (!jag)
    return;

  for (ALL_LIST_ELEMENTS(jag->sources, node, nnode, js))
    {
      if (js->up == up)
        break;
    }

  if (js)
    {
      js->up = NULL;
      listnode_delete(jag->sources, js);
      XFREE(MTYPE_PIM_JP_AGG_SOURCE, js);
    }

  if (jag->sources->count == 0)
    {
      list_delete(jag->sources);
      jag->sources = NULL;
      listnode_delete(group, jag);
      XFREE(MTYPE_PIM_JP_AGG_GROUP, jag);
    }

}

int
pim_jp_agg_is_in_list (struct list *group, struct pim_upstream *up)
{
  struct listnode *node, *nnode;
  struct pim_jp_agg_group *jag = NULL;
  struct pim_jp_sources *js = NULL;

  for (ALL_LIST_ELEMENTS (group, node, nnode, jag))
    {
      if (jag->group.s_addr == up->sg.grp.s_addr)
        break;
    }

  if (!jag)
    return 0;

  for (ALL_LIST_ELEMENTS(jag->sources, node, nnode, js))
    {
      if (js->up == up)
        return 1;
    }

  return 0;
 }

//#define PIM_JP_AGG_DEBUG 1
/*
 * For the given upstream, check all the neighbor
 * jp_agg lists and ensure that it is not
 * in another list
 *
 * *IF* ignore is true we can skip
 * up->rpf.source_nexthop.interface particular interface for checking
 *
 * This is a debugging function, Probably
 * can be safely compiled out in real
 * builds
 */
void
pim_jp_agg_upstream_verification (struct pim_upstream *up, bool ignore)
{
#ifdef PIM_JP_AGG_DEBUG
  struct listnode *node;
  struct interface *ifp;

  for (ALL_LIST_ELEMENTS_RO (vrf_iflist (VRF_DEFAULT), node, ifp))
    {
      struct pim_interface *pim_ifp = ifp->info;
      struct listnode *nnode;

      if (ignore && ifp == up->rpf.source_nexthop.interface)
        continue;

      if (pim_ifp)
        {
          struct pim_neighbor *neigh;
          for (ALL_LIST_ELEMENTS_RO(pim_ifp->pim_neighbor_list, nnode, neigh))
            {
              assert (!pim_jp_agg_is_in_list(neigh->upstream_jp_agg, up));
            }
        }
    }
#else
  return;
#endif
}

void
pim_jp_agg_add_group (struct list *group, struct pim_upstream *up, bool is_join)
{
  struct listnode *node, *nnode;
  struct pim_jp_agg_group *jag = NULL;
  struct pim_jp_sources *js = NULL;

  for (ALL_LIST_ELEMENTS(group, node, nnode, jag))
    {
      if (jag->group.s_addr == up->sg.grp.s_addr)
        break;
    }

  if (!jag)
    {
      jag = XCALLOC(MTYPE_PIM_JP_AGG_GROUP, sizeof (struct pim_jp_agg_group));
      jag->group.s_addr = up->sg.grp.s_addr;
      jag->sources = list_new();
      jag->sources->cmp = pim_jp_agg_src_cmp;
      jag->sources->del = (void (*)(void *))pim_jp_agg_src_free;
      listnode_add_sort (group, jag);
    }

  for (ALL_LIST_ELEMENTS(jag->sources, node, nnode, js))
    {
      if (js->up == up)
        break;
    }

  if (!js)
    {
      js = XCALLOC(MTYPE_PIM_JP_AGG_SOURCE, sizeof (struct pim_jp_sources));
      js->up = up;
      js->is_join = is_join;
      listnode_add_sort (jag->sources, js);
    }
  else
    {
      if (js->is_join != is_join)
        {
          listnode_delete(jag->sources, js);
          js->is_join = is_join;
          listnode_add_sort (jag->sources, js);
        }
    }
}

void
pim_jp_agg_switch_interface (struct pim_rpf *orpf,
                             struct pim_rpf *nrpf,
                             struct pim_upstream *up)
{
  struct pim_iface_upstream_switch *opius;
  struct pim_iface_upstream_switch *npius;

  opius = pim_jp_agg_get_interface_upstream_switch_list(orpf);
  npius = pim_jp_agg_get_interface_upstream_switch_list(nrpf);

  /*
   * RFC 4601: 4.5.7.  Sending (S,G) Join/Prune Messages
   *
   * Transitions from Joined State
   *
   * RPF'(S,G) changes not due to an Assert
   *
   * The upstream (S,G) state machine remains in Joined
   * state. Send Join(S,G) to the new upstream neighbor, which is
   * the new value of RPF'(S,G).  Send Prune(S,G) to the old
   * upstream neighbor, which is the old value of RPF'(S,G).  Set
   * the Join Timer (JT) to expire after t_periodic seconds.
   */

  /* send Prune(S,G) to the old upstream neighbor */
  pim_jp_agg_add_group (opius->us, up, false);

  /* send Join(S,G) to the current upstream neighbor */
  pim_jp_agg_add_group (npius->us, up, true);

}


void
pim_jp_agg_single_upstream_send (struct pim_rpf *rpf,
                                 struct pim_upstream *up,
                                 bool is_join)
{
  static struct list *groups = NULL;
  static struct pim_jp_agg_group jag;
  static struct pim_jp_sources js;

  static bool first = true;

  /* skip JP upstream messages if source is directly connected */
  if (pim_if_connected_to_source (rpf->source_nexthop.interface, up->sg.src))
      return;

  if (first)
    {
      groups = list_new();

      jag.sources = list_new();

      listnode_add(groups, &jag);
      listnode_add(jag.sources, &js);

      first = false;
    }

  jag.group.s_addr = up->sg.grp.s_addr;
  js.up = up;
  js.is_join = is_join;

  pim_joinprune_send(rpf, groups);
}