pimd/pim_rp.c

   1 /*
   2  * PIM for Quagga
   3  * Copyright (C) 2015 Cumulus Networks, Inc.
   4  * Donald Sharp
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; see the file COPYING; if not, write to the
  18  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  19  * MA 02110-1301 USA
  20  */
  21 #include <zebra.h>
  22
  23 #include "log.h"
  24 #include "network.h"
  25
  26 #include "pimd.h"
  27 #include "pim_str.h"
  28 #include "pim_rp.h"
  29 #include "pim_str.h"
  30 #include "pim_rpf.h"
  31
  32 static int i_am_rp = 0;
  33
  34 /*
  35  * Checks to see if we should elect ourself the actual RP
  36  */
  37 void
  38 pim_rp_check_rp (struct in_addr old, struct in_addr new)
  39 {
  40   if (PIM_DEBUG_ZEBRA) {
  41     char sold[100];
  42     char snew[100];
  43     char rp[100];
  44     pim_inet4_dump("<rp?>", qpim_rp.rpf_addr, rp, sizeof(rp));
  45     pim_inet4_dump("<old?>", old, sold, sizeof(sold));
  46     pim_inet4_dump("<new?>", new, snew, sizeof(snew));
  47     zlog_debug("%s: %s for old %s new %s", __func__, rp, sold, snew );
  48   }
  49
  50   if (qpim_rp.rpf_addr.s_addr == INADDR_NONE)
  51     return;
  52
  53   if (new.s_addr == qpim_rp.rpf_addr.s_addr)
  54     {
  55       i_am_rp = 1;
  56       return;
  57     }
  58
  59   if (old.s_addr == qpim_rp.rpf_addr.s_addr)
  60     {
  61       i_am_rp = 0;
  62       return;
  63     }
  64 }
  65
  66 /*
  67  * I_am_RP(G) is true if the group-to-RP mapping indicates that
  68  * this router is the RP for the group.
  69  *
  70  * Since we only have static RP, all groups are part of this RP
  71  */
  72 int
  73 pim_rp_i_am_rp (struct in_addr group)
  74 {
  75   return i_am_rp;
  76 }
  77
  78 /*
  79  * RP(G)
  80  *
  81  * Return the RP that the Group belongs too.
  82  */
  83 struct pim_rpf *
  84 pim_rp_g (struct in_addr group)
  85 {
  86   /*
  87    * For staticly configured RP, it is always the qpim_rp
  88    */
  89   pim_nexthop_lookup(&qpim_rp.source_nexthop, qpim_rp.rpf_addr);
  90   return(&qpim_rp);
  91 }
  92
  93 /*
  94  * Set the upstream IP address we want to talk to based upon
  95  * the rp configured and the source address
  96  *
  97  * If we have don't have a RP configured and the source address is *
  98  * then return failure.
  99  *
 100  */
 101 int
 102 pim_rp_set_upstream_addr (struct in_addr *up, struct in_addr source)
 103 {
 104   if ((qpim_rp.rpf_addr.s_addr == INADDR_NONE) && (source.s_addr == INADDR_ANY))
 105     {
 106       if (PIM_DEBUG_PIM_TRACE)
 107         zlog_debug("%s: Received a (*,G) with no RP configured", __PRETTY_FUNCTION__);
 108       return 0;
 109     }
 110
 111   *up = (source.s_addr == INADDR_ANY) ? qpim_rp.rpf_addr : source;
 112
 113   return 1;
 114 }