pimd/pim_msg.c

   1 /*
   2   PIM for Quagga
   3   Copyright (C) 2008  Everton da Silva Marques
   4
   5   This program is free software; you can redistribute it and/or modify
   6   it under the terms of the GNU General Public License as published by
   7   the Free Software Foundation; either version 2 of the License, or
   8   (at your option) any later version.
   9
  10   This program is distributed in the hope that it will be useful, but
  11   WITHOUT ANY WARRANTY; without even the implied warranty of
  12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13   General Public License for more details.
  14
  15   You should have received a copy of the GNU General Public License
  16   along with this program; see the file COPYING; if not, write to the
  17   Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  18   MA 02110-1301 USA
  19 */
  20
  21 #include <zebra.h>
  22
  23 #include "if.h"
  24 #include "log.h"
  25 #include "prefix.h"
  26 #include "vty.h"
  27 #include "plist.h"
  28
  29 #include "pimd.h"
  30 #include "pim_vty.h"
  31 #include "pim_pim.h"
  32 #include "pim_msg.h"
  33 #include "pim_util.h"
  34 #include "pim_str.h"
  35 #include "pim_iface.h"
  36 #include "pim_rp.h"
  37 #include "pim_rpf.h"
  38 #include "pim_register.h"
  39 #include "pim_jp_agg.h"
  40
  41 void pim_msg_build_header(uint8_t *pim_msg, size_t pim_msg_size, uint8_t pim_msg_type)
  42 {
  43   struct pim_msg_header *header = (struct pim_msg_header *)pim_msg;
  44
  45   /*
  46    * Write header
  47    */
  48   header->ver = PIM_PROTO_VERSION;
  49   header->type = pim_msg_type;
  50   header->reserved = 0;
  51
  52
  53   header->checksum = 0;
  54   /*
  55    * The checksum for Registers is done only on the first 8 bytes of the packet,
  56    * including the PIM header and the next 4 bytes, excluding the data packet portion
  57    */
  58   if (pim_msg_type == PIM_MSG_TYPE_REGISTER)
  59     header->checksum = in_cksum (pim_msg, PIM_MSG_REGISTER_LEN);
  60   else
  61     header->checksum = in_cksum (pim_msg, pim_msg_size);
  62 }
  63
  64 uint8_t *pim_msg_addr_encode_ipv4_ucast(uint8_t *buf, struct in_addr addr)
  65 {
  66   buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  67   buf[1] = '\0';    /* native encoding */
  68   memcpy(buf+2, &addr, sizeof(struct in_addr));
  69
  70   return buf + PIM_ENCODED_IPV4_UCAST_SIZE;
  71 }
  72
  73 uint8_t *pim_msg_addr_encode_ipv4_group(uint8_t *buf, struct in_addr addr)
  74 {
  75   buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  76   buf[1] = '\0';    /* native encoding */
  77   buf[2] = '\0';    /* reserved */
  78   buf[3] = 32;      /* mask len */
  79   memcpy(buf+4, &addr, sizeof(struct in_addr));
  80
  81   return buf + PIM_ENCODED_IPV4_GROUP_SIZE;
  82 }
  83
  84 uint8_t *
  85 pim_msg_addr_encode_ipv4_source(uint8_t *buf,
  86                                 struct in_addr addr, uint8_t bits)
  87 {
  88   buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  89   buf[1] = '\0';    /* native encoding */
  90   buf[2] = bits;
  91   buf[3] = 32;      /* mask len */
  92   memcpy(buf+4, &addr, sizeof(struct in_addr));
  93
  94   return buf + PIM_ENCODED_IPV4_SOURCE_SIZE;
  95 }
  96
  97 /*
  98  * For the given 'struct pim_jp_sources' list
  99  * determine the size_t it would take up.
 100  */
 101 size_t
 102 pim_msg_get_jp_group_size (struct list *sources)
 103 {
 104   struct pim_jp_sources *js;
 105   size_t size = 0;
 106
 107   size += sizeof (struct pim_encoded_group_ipv4);
 108   size += 4;  // Joined sources (2) + Pruned Sources (2)
 109
 110   size += sizeof (struct pim_encoded_source_ipv4) * sources->count;
 111
 112   js = listgetdata(listhead(sources));
 113   if (js && js->up->sg.src.s_addr == INADDR_ANY)
 114     {
 115       struct pim_upstream *child, *up;
 116       struct listnode *up_node;
 117
 118       up = js->up;
 119       if (PIM_DEBUG_PIM_PACKETS)
 120         zlog_debug ("%s: Considering (%s) children for (S,G,rpt) prune",
 121                     __PRETTY_FUNCTION__, up->sg_str);
 122
 123       for (ALL_LIST_ELEMENTS_RO (up->sources, up_node, child))
 124         {
 125           if (child->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
 126             {
 127               if (!pim_rpf_is_same(&up->rpf, &child->rpf))
 128                 {
 129                   size += sizeof (struct pim_encoded_source_ipv4);
 130                   PIM_UPSTREAM_FLAG_SET_SEND_SG_RPT_PRUNE(child->flags);
 131                   if (PIM_DEBUG_PIM_PACKETS)
 132                     zlog_debug ("%s: SPT Bit and RPF'(%s) != RPF'(S,G): Add Prune (%s,rpt) to compound message",
 133                                 __PRETTY_FUNCTION__, up->sg_str, child->sg_str);
 134                 }
 135               else
 136                 if (PIM_DEBUG_PIM_PACKETS)
 137                   zlog_debug ("%s: SPT Bit and RPF'(%s) == RPF'(S,G): Not adding Prune for (%s,rpt)",
 138                               __PRETTY_FUNCTION__, up->sg_str, child->sg_str);
 139             }
 140           else if (pim_upstream_is_sg_rpt (child))
 141             {
 142               if (pim_upstream_empty_inherited_olist (child))
 143                 {
 144                   size += sizeof (struct pim_encoded_source_ipv4);
 145                   PIM_UPSTREAM_FLAG_SET_SEND_SG_RPT_PRUNE(child->flags);
 146                   if (PIM_DEBUG_PIM_PACKETS)
 147                     zlog_debug ("%s: inherited_olist(%s,rpt) is NULL, Add Prune to compound message",
 148                                 __PRETTY_FUNCTION__, child->sg_str);
 149                 }
 150               else if (!pim_rpf_is_same (&up->rpf, &child->rpf))
 151                 {
 152                   size += sizeof (struct pim_encoded_source_ipv4);
 153                   PIM_UPSTREAM_FLAG_SET_SEND_SG_RPT_PRUNE(child->flags);
 154                   if (PIM_DEBUG_PIM_PACKETS)
 155                     zlog_debug ("%s: RPF'(%s) != RPF'(%s,rpt), Add Prune to compound message",
 156                                 __PRETTY_FUNCTION__, up->sg_str, child->sg_str);
 157                 }
 158               else
 159                 if (PIM_DEBUG_PIM_PACKETS)
 160                   zlog_debug ("%s: RPF'(%s) == RPF'(%s,rpt), Do not add Prune to compound message",
 161                               __PRETTY_FUNCTION__, up->sg_str, child->sg_str);
 162             }
 163           else
 164             if (PIM_DEBUG_PIM_PACKETS)
 165               zlog_debug ("%s: SPT bit is not set for (%s)",
 166                           __PRETTY_FUNCTION__, child->sg_str);
 167         }
 168     }
 169   return size;
 170 }
 171
 172 size_t
 173 pim_msg_build_jp_groups (struct pim_jp_groups *grp, struct pim_jp_agg_group *sgs, size_t size)
 174 {
 175   struct listnode *node, *nnode;
 176   struct pim_jp_sources *source;
 177   struct pim_upstream *up = NULL;
 178   struct in_addr stosend;
 179   uint8_t bits;
 180   uint8_t tgroups = 0;
 181
 182   memset (grp, 0, size);
 183   pim_msg_addr_encode_ipv4_group ((uint8_t *)&grp->g, sgs->group);
 184
 185   for (ALL_LIST_ELEMENTS(sgs->sources, node, nnode, source))
 186     {
 187       /* number of joined/pruned sources */
 188       if (source->is_join)
 189         grp->joins++;
 190       else
 191         grp->prunes++;
 192
 193       if (source->up->sg.src.s_addr == INADDR_ANY)
 194         {
 195           struct pim_rpf *rpf = pim_rp_g (source->up->sg.grp);
 196           bits = PIM_ENCODE_SPARSE_BIT | PIM_ENCODE_WC_BIT | PIM_ENCODE_RPT_BIT;
 197           stosend = rpf->rpf_addr.u.prefix4;
 198           /* Only Send SGRpt in case of *,G Join */
 199           if (source->is_join)
 200             up = source->up;
 201         }
 202       else
 203         {
 204           bits = PIM_ENCODE_SPARSE_BIT;
 205           stosend = source->up->sg.src;
 206         }
 207
 208       pim_msg_addr_encode_ipv4_source ((uint8_t *)&grp->s[tgroups], stosend, bits);
 209       tgroups++;
 210     }
 211
 212   if (up)
 213     {
 214       struct pim_upstream *child;
 215
 216       for (ALL_LIST_ELEMENTS(up->sources, node, nnode, child))
 217         {
 218           if (PIM_UPSTREAM_FLAG_TEST_SEND_SG_RPT_PRUNE(child->flags))
 219             {
 220               pim_msg_addr_encode_ipv4_source ((uint8_t *)&grp->s[tgroups],
 221                                                child->sg.src,
 222                                                PIM_ENCODE_SPARSE_BIT | PIM_ENCODE_RPT_BIT);
 223               tgroups++;
 224               PIM_UPSTREAM_FLAG_UNSET_SEND_SG_RPT_PRUNE(child->flags);
 225               grp->prunes++;
 226             }
 227         }
 228     }
 229
 230   grp->joins = htons(grp->joins);
 231   grp->prunes = htons(grp->prunes);
 232
 233   return size;
 234 }