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