pimd/pim_ssm.c

   1 /*
   2  * IP SSM ranges for FRR
   3  * Copyright (C) 2017 Cumulus Networks, Inc.
   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 <lib/linklist.h>
  23 #include <lib/prefix.h>
  24 #include <lib/vty.h>
  25 #include <lib/vrf.h>
  26 #include <lib/plist.h>
  27 #include <lib/lib_errors.h>
  28
  29 #include "pimd.h"
  30 #include "pim_ssm.h"
  31 #include "pim_zebra.h"
  32
  33 static void pim_ssm_range_reevaluate(struct pim_instance *pim)
  34 {
  35         /* 1. Setup register state for (S,G) entries if G has changed from SSM
  36          * to
  37          *    ASM.
  38          * 2. check existing (*,G) IGMP registrations to see if they are
  39          * still ASM. if they are now SSM delete them.
  40          * 3. Allow channel setup for IGMP (*,G) members if G is now ASM
  41          * 4. I could tear down all (*,G), (S,G,rpt) states. But that is an
  42          * unnecessary sladge hammer and may not be particularly useful as it is
  43          * likely the SPT switchover has already happened for flows along such
  44          * RPTs.
  45          * As for the RPT states it seems that the best thing to do is let them
  46          * age
  47          * out gracefully. As long as the FHR and LHR do the right thing RPTs
  48          * will
  49          * disappear in time for SSM groups.
  50          */
  51         pim_upstream_register_reevaluate(pim);
  52         igmp_source_forward_reevaluate_all(pim);
  53 }
  54
  55 void pim_ssm_prefix_list_update(struct pim_instance *pim,
  56                                 struct prefix_list *plist)
  57 {
  58         struct pim_ssm *ssm = pim->ssm_info;
  59
  60         if (!ssm->plist_name
  61             || strcmp(ssm->plist_name, prefix_list_name(plist))) {
  62                 /* not ours */
  63                 return;
  64         }
  65
  66         pim_ssm_range_reevaluate(pim);
  67 }
  68
  69 static int pim_is_grp_standard_ssm(struct prefix *group)
  70 {
  71         static int first = 1;
  72         static struct prefix group_ssm;
  73
  74         if (first) {
  75                 if (!str2prefix(PIM_SSM_STANDARD_RANGE, &group_ssm))
  76                         flog_err(EC_LIB_DEVELOPMENT,
  77                                  "%s: Failure to Read Group Address: %s",
  78                                  __PRETTY_FUNCTION__, PIM_SSM_STANDARD_RANGE);
  79
  80                 first = 0;
  81         }
  82
  83         return prefix_match(&group_ssm, group);
  84 }
  85
  86 int pim_is_grp_ssm(struct pim_instance *pim, struct in_addr group_addr)
  87 {
  88         struct pim_ssm *ssm;
  89         struct prefix group;
  90         struct prefix_list *plist;
  91
  92         memset(&group, 0, sizeof(group));
  93         group.family = AF_INET;
  94         group.u.prefix4 = group_addr;
  95         group.prefixlen = 32;
  96
  97         ssm = pim->ssm_info;
  98         if (!ssm->plist_name) {
  99                 return pim_is_grp_standard_ssm(&group);
 100         }
 101
 102         plist = prefix_list_lookup(AFI_IP, ssm->plist_name);
 103         if (!plist)
 104                 return 0;
 105
 106         return (prefix_list_apply(plist, &group) == PREFIX_PERMIT);
 107 }
 108
 109 int pim_ssm_range_set(struct pim_instance *pim, vrf_id_t vrf_id,
 110                       const char *plist_name)
 111 {
 112         struct pim_ssm *ssm;
 113         int change = 0;
 114
 115         if (vrf_id != pim->vrf_id)
 116                 return PIM_SSM_ERR_NO_VRF;
 117
 118         ssm = pim->ssm_info;
 119         if (plist_name) {
 120                 if (ssm->plist_name) {
 121                         if (!strcmp(ssm->plist_name, plist_name))
 122                                 return PIM_SSM_ERR_DUP;
 123                         XFREE(MTYPE_PIM_FILTER_NAME, ssm->plist_name);
 124                 }
 125                 ssm->plist_name = XSTRDUP(MTYPE_PIM_FILTER_NAME, plist_name);
 126                 change = 1;
 127         } else {
 128                 if (ssm->plist_name) {
 129                         change = 1;
 130                         XFREE(MTYPE_PIM_FILTER_NAME, ssm->plist_name);
 131                 }
 132         }
 133
 134         if (change)
 135                 pim_ssm_range_reevaluate(pim);
 136
 137         return PIM_SSM_ERR_NONE;
 138 }
 139
 140 void *pim_ssm_init(void)
 141 {
 142         struct pim_ssm *ssm;
 143
 144         ssm = XCALLOC(MTYPE_PIM_SSM_INFO, sizeof(*ssm));
 145
 146         return ssm;
 147 }
 148
 149 void pim_ssm_terminate(struct pim_ssm *ssm)
 150 {
 151         if (!ssm)
 152                 return;
 153
 154         if (ssm->plist_name)
 155                 XFREE(MTYPE_PIM_FILTER_NAME, ssm->plist_name);
 156
 157         XFREE(MTYPE_PIM_SSM_INFO, ssm);
 158 }