pimd: Join/Prune Aggregation

[mirror_frr.git] / pimd / pim_msg.c

/*
  PIM for Quagga
  Copyright (C) 2008  Everton da Silva Marques

  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 "if.h"
#include "log.h"
#include "prefix.h"
#include "vty.h"
#include "plist.h"

#include "pimd.h"
#include "pim_vty.h"
#include "pim_pim.h"
#include "pim_msg.h"
#include "pim_util.h"
#include "pim_str.h"
#include "pim_iface.h"
#include "pim_rp.h"
#include "pim_rpf.h"
#include "pim_register.h"
#include "pim_jp_agg.h"

void pim_msg_build_header(uint8_t *pim_msg, size_t pim_msg_size, uint8_t pim_msg_type)
{
  struct pim_msg_header *header = (struct pim_msg_header *)pim_msg;

  /*
   * Write header
   */
  header->ver = PIM_PROTO_VERSION;
  header->type = pim_msg_type;
  header->reserved = 0;


  header->checksum = 0;
  /*
   * The checksum for Registers is done only on the first 8 bytes of the packet,
   * including the PIM header and the next 4 bytes, excluding the data packet portion
   */
  if (pim_msg_type == PIM_MSG_TYPE_REGISTER)
    header->checksum = in_cksum (pim_msg, PIM_MSG_REGISTER_LEN);
  else
    header->checksum = in_cksum (pim_msg, pim_msg_size);
}

uint8_t *pim_msg_addr_encode_ipv4_ucast(uint8_t *buf, struct in_addr addr)
{
  buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  buf[1] = '\0';    /* native encoding */
  memcpy(buf+2, &addr, sizeof(struct in_addr));

  return buf + PIM_ENCODED_IPV4_UCAST_SIZE;
}

uint8_t *pim_msg_addr_encode_ipv4_group(uint8_t *buf, struct in_addr addr)
{
  buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  buf[1] = '\0';    /* native encoding */
  buf[2] = '\0';    /* reserved */
  buf[3] = 32;      /* mask len */
  memcpy(buf+4, &addr, sizeof(struct in_addr));

  return buf + PIM_ENCODED_IPV4_GROUP_SIZE;
}

uint8_t *
pim_msg_addr_encode_ipv4_source(uint8_t *buf,
                                struct in_addr addr, uint8_t bits)
{
  buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  buf[1] = '\0';    /* native encoding */
  buf[2] = bits;
  buf[3] = 32;      /* mask len */
  memcpy(buf+4, &addr, sizeof(struct in_addr));

  return buf + PIM_ENCODED_IPV4_SOURCE_SIZE;
}

/*
 * For the given 'struct pim_jp_sources' list
 * determine the size_t it would take up.
 */
size_t
pim_msg_get_jp_group_size (struct list *sources)
{
  size_t size = 0;

  size += sizeof (struct pim_encoded_group_ipv4);
  size += 4;  // Joined sources (2) + Pruned Sources (2)

  size += sizeof (struct pim_encoded_source_ipv4) * sources->count;

  return size;
}

size_t
pim_msg_build_jp_groups (struct pim_jp_groups *grp, struct pim_jp_agg_group *sgs)
{
  struct listnode *node, *nnode;
  struct pim_jp_sources *source;
  struct in_addr stosend;
  uint8_t bits;
  size_t size = pim_msg_get_jp_group_size (sgs->sources);
  uint8_t tgroups = 0;

  memset (grp, 0, size);
  pim_msg_addr_encode_ipv4_group ((uint8_t *)&grp->g, sgs->group);

  for (ALL_LIST_ELEMENTS(sgs->sources, node, nnode, source))
    {
      /* number of joined/pruned sources */
      if (source->is_join)
        grp->joins++;
      else
        grp->prunes++;

      if (source->up->sg.src.s_addr == INADDR_ANY)
        {
          struct pim_rpf *rpf = pim_rp_g (source->up->sg.grp);
          bits = PIM_ENCODE_SPARSE_BIT | PIM_ENCODE_WC_BIT | PIM_ENCODE_RPT_BIT;
          stosend = rpf->rpf_addr.u.prefix4;
        }
      else
        {
          bits = PIM_ENCODE_SPARSE_BIT;
          stosend = source->up->sg.src;
        }

      pim_msg_addr_encode_ipv4_source ((uint8_t *)&grp->s[tgroups], stosend, bits);
      tgroups++;
    }

  grp->joins = htons(grp->joins);
  grp->prunes = htons(grp->prunes);
  /*
   * This is not implemented correctly at this point in time
   * Make it stop.
   */
#if 0
  if (up->sg.src.s_addr == INADDR_ANY)
    {
      struct pim_upstream *child;
      struct listnode *up_node;
      int send_prune = 0;

      zlog_debug ("%s: Considering (%s) children for (S,G,rpt) prune",
                  __PRETTY_FUNCTION__, up->sg_str);
      for (ALL_LIST_ELEMENTS_RO (up->sources, up_node, child))
        {
          if (child->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
            {
              if (!pim_rpf_is_same(&up->rpf, &child->rpf))
                {
                  send_prune = 1;
                  if (PIM_DEBUG_PIM_PACKETS)
                    zlog_debug ("%s: SPT Bit and RPF'(%s) != RPF'(S,G): Add Prune (%s,rpt) to compound message",
                                __PRETTY_FUNCTION__, up->sg_str, child->sg_str);
                }
              else
                if (PIM_DEBUG_PIM_PACKETS)
                  zlog_debug ("%s: SPT Bit and RPF'(%s) == RPF'(S,G): Not adding Prune for (%s,rpt)",
                              __PRETTY_FUNCTION__, up->sg_str, child->sg_str);
            }
          else if (pim_upstream_is_sg_rpt (child))
            {
              if (pim_upstream_empty_inherited_olist (child))
                {
                  send_prune = 1;
                  if (PIM_DEBUG_PIM_PACKETS)
                    zlog_debug ("%s: inherited_olist(%s,rpt) is NULL, Add Prune to compound message",
                                __PRETTY_FUNCTION__, child->sg_str);
                }
              else if (!pim_rpf_is_same (&up->rpf, &child->rpf))
                {
                  send_prune = 1;
                  if (PIM_DEBUG_PIM_PACKETS)
                    zlog_debug ("%s: RPF'(%s) != RPF'(%s,rpt), Add Prune to compound message",
                                __PRETTY_FUNCTION__, up->sg_str, child->sg_str);
                }
              else
                if (PIM_DEBUG_PIM_PACKETS)
                  zlog_debug ("%s: RPF'(%s) == RPF'(%s,rpt), Do not add Prune to compound message",
                              __PRETTY_FUNCTION__, up->sg_str, child->sg_str);
            }
          else
            if (PIM_DEBUG_PIM_PACKETS)
              zlog_debug ("%s: SPT bit is not set for (%s)",
                          __PRETTY_FUNCTION__, child->sg_str);
          if (send_prune)
            {
              pim_msg_curr = pim_msg_addr_encode_ipv4_source (pim_msg_curr, remain,
                                                              child->sg.src,
                                                              PIM_ENCODE_SPARSE_BIT | PIM_ENCODE_RPT_BIT);
              remain = pim_msg_curr - pim_msg;
              *prunes = htons(ntohs(*prunes) + 1);
              send_prune = 0;
            }
        }
    }
#endif

  return size;
}