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 along
  16  * with this program; see the file COPYING; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  18  */
  19
  20 #include <zebra.h>
  21
  22 #include "if.h"
  23 #include "log.h"
  24 #include "prefix.h"
  25 #include "vty.h"
  26 #include "plist.h"
  27
  28 #include "pimd.h"
  29 #include "pim_vty.h"
  30 #include "pim_pim.h"
  31 #include "pim_msg.h"
  32 #include "pim_util.h"
  33 #include "pim_str.h"
  34 #include "pim_iface.h"
  35 #include "pim_rp.h"
  36 #include "pim_rpf.h"
  37 #include "pim_register.h"
  38 #include "pim_jp_agg.h"
  39
  40 void pim_msg_build_header(uint8_t *pim_msg, size_t pim_msg_size,
  41                           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
  56          * packet,
  57          * including the PIM header and the next 4 bytes, excluding the data
  58          * packet portion
  59          */
  60         if (pim_msg_type == PIM_MSG_TYPE_REGISTER)
  61                 header->checksum = in_cksum(pim_msg, PIM_MSG_REGISTER_LEN);
  62         else
  63                 header->checksum = in_cksum(pim_msg, pim_msg_size);
  64 }
  65
  66 uint8_t *pim_msg_addr_encode_ipv4_ucast(uint8_t *buf, struct in_addr addr)
  67 {
  68         buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  69         buf[1] = '\0';                        /* native encoding */
  70         memcpy(buf + 2, &addr, sizeof(struct in_addr));
  71
  72         return buf + PIM_ENCODED_IPV4_UCAST_SIZE;
  73 }
  74
  75 uint8_t *pim_msg_addr_encode_ipv4_group(uint8_t *buf, struct in_addr addr)
  76 {
  77         buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  78         buf[1] = '\0';                        /* native encoding */
  79         buf[2] = '\0';                        /* reserved */
  80         buf[3] = 32;                          /* mask len */
  81         memcpy(buf + 4, &addr, sizeof(struct in_addr));
  82
  83         return buf + PIM_ENCODED_IPV4_GROUP_SIZE;
  84 }
  85
  86 uint8_t *pim_msg_addr_encode_ipv4_source(uint8_t *buf, struct in_addr addr,
  87                                          uint8_t bits)
  88 {
  89         buf[0] = PIM_MSG_ADDRESS_FAMILY_IPV4; /* addr family */
  90         buf[1] = '\0';                        /* native encoding */
  91         buf[2] = bits;
  92         buf[3] = 32; /* mask len */
  93         memcpy(buf + 4, &addr, sizeof(struct in_addr));
  94
  95         return buf + PIM_ENCODED_IPV4_SOURCE_SIZE;
  96 }
  97
  98 /*
  99  * For the given 'struct pim_jp_sources' list
 100  * determine the size_t it would take up.
 101  */
 102 size_t 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                 struct pim_upstream *child, *up;
 115                 struct listnode *up_node;
 116
 117                 up = js->up;
 118                 if (PIM_DEBUG_PIM_PACKETS)
 119                         zlog_debug(
 120                                 "%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                         if (child->sptbit == PIM_UPSTREAM_SPTBIT_TRUE) {
 125                                 if (!pim_rpf_is_same(&up->rpf, &child->rpf)) {
 126                                         size += sizeof(
 127                                                 struct pim_encoded_source_ipv4);
 128                                         PIM_UPSTREAM_FLAG_SET_SEND_SG_RPT_PRUNE(
 129                                                 child->flags);
 130                                         if (PIM_DEBUG_PIM_PACKETS)
 131                                                 zlog_debug(
 132                                                         "%s: SPT Bit and RPF'(%s) != RPF'(S,G): Add Prune (%s,rpt) to compound message",
 133                                                         __PRETTY_FUNCTION__,
 134                                                         up->sg_str,
 135                                                         child->sg_str);
 136                                 } else if (PIM_DEBUG_PIM_PACKETS)
 137                                         zlog_debug(
 138                                                 "%s: SPT Bit and RPF'(%s) == RPF'(S,G): Not adding Prune for (%s,rpt)",
 139                                                 __PRETTY_FUNCTION__, up->sg_str,
 140                                                 child->sg_str);
 141                         } else if (pim_upstream_is_sg_rpt(child)) {
 142                                 if (pim_upstream_empty_inherited_olist(child)) {
 143                                         size += sizeof(
 144                                                 struct pim_encoded_source_ipv4);
 145                                         PIM_UPSTREAM_FLAG_SET_SEND_SG_RPT_PRUNE(
 146                                                 child->flags);
 147                                         if (PIM_DEBUG_PIM_PACKETS)
 148                                                 zlog_debug(
 149                                                         "%s: inherited_olist(%s,rpt) is NULL, Add Prune to compound message",
 150                                                         __PRETTY_FUNCTION__,
 151                                                         child->sg_str);
 152                                 } else if (!pim_rpf_is_same(&up->rpf,
 153                                                             &child->rpf)) {
 154                                         size += sizeof(
 155                                                 struct pim_encoded_source_ipv4);
 156                                         PIM_UPSTREAM_FLAG_SET_SEND_SG_RPT_PRUNE(
 157                                                 child->flags);
 158                                         if (PIM_DEBUG_PIM_PACKETS)
 159                                                 zlog_debug(
 160                                                         "%s: RPF'(%s) != RPF'(%s,rpt), Add Prune to compound message",
 161                                                         __PRETTY_FUNCTION__,
 162                                                         up->sg_str,
 163                                                         child->sg_str);
 164                                 } else if (PIM_DEBUG_PIM_PACKETS)
 165                                         zlog_debug(
 166                                                 "%s: RPF'(%s) == RPF'(%s,rpt), Do not add Prune to compound message",
 167                                                 __PRETTY_FUNCTION__, up->sg_str,
 168                                                 child->sg_str);
 169                         } else if (PIM_DEBUG_PIM_PACKETS)
 170                                 zlog_debug("%s: SPT bit is not set for (%s)",
 171                                            __PRETTY_FUNCTION__, child->sg_str);
 172                 }
 173         }
 174         return size;
 175 }
 176
 177 size_t pim_msg_build_jp_groups(struct pim_jp_groups *grp,
 178                                struct pim_jp_agg_group *sgs, size_t size)
 179 {
 180         struct listnode *node, *nnode;
 181         struct pim_jp_sources *source;
 182         struct pim_upstream *up = NULL;
 183         struct in_addr stosend;
 184         uint8_t bits;
 185         uint8_t tgroups = 0;
 186
 187         memset(grp, 0, size);
 188         pim_msg_addr_encode_ipv4_group((uint8_t *)&grp->g, sgs->group);
 189
 190         for (ALL_LIST_ELEMENTS(sgs->sources, node, nnode, source)) {
 191                 /* number of joined/pruned sources */
 192                 if (source->is_join)
 193                         grp->joins++;
 194                 else
 195                         grp->prunes++;
 196
 197                 if (source->up->sg.src.s_addr == INADDR_ANY) {
 198                         struct pim_rpf *rpf = pim_rp_g(source->up->sg.grp);
 199                         bits = PIM_ENCODE_SPARSE_BIT | PIM_ENCODE_WC_BIT
 200                                | PIM_ENCODE_RPT_BIT;
 201                         stosend = rpf->rpf_addr.u.prefix4;
 202                         /* Only Send SGRpt in case of *,G Join */
 203                         if (source->is_join)
 204                                 up = source->up;
 205                 } else {
 206                         bits = PIM_ENCODE_SPARSE_BIT;
 207                         stosend = source->up->sg.src;
 208                 }
 209
 210                 pim_msg_addr_encode_ipv4_source((uint8_t *)&grp->s[tgroups],
 211                                                 stosend, bits);
 212                 tgroups++;
 213         }
 214
 215         if (up) {
 216                 struct pim_upstream *child;
 217
 218                 for (ALL_LIST_ELEMENTS(up->sources, node, nnode, child)) {
 219                         if (PIM_UPSTREAM_FLAG_TEST_SEND_SG_RPT_PRUNE(
 220                                     child->flags)) {
 221                                 pim_msg_addr_encode_ipv4_source(
 222                                         (uint8_t *)&grp->s[tgroups],
 223                                         child->sg.src,
 224                                         PIM_ENCODE_SPARSE_BIT
 225                                                 | PIM_ENCODE_RPT_BIT);
 226                                 tgroups++;
 227                                 PIM_UPSTREAM_FLAG_UNSET_SEND_SG_RPT_PRUNE(
 228                                         child->flags);
 229                                 grp->prunes++;
 230                         }
 231                 }
 232         }
 233
 234         grp->joins = htons(grp->joins);
 235         grp->prunes = htons(grp->prunes);
 236
 237         return size;
 238 }