bgpd/bgp_community_alias.c

   1 /* BGP community, large-community aliasing.
   2  *
   3  * Copyright (C) 2021 Donatas Abraitis <donatas.abraitis@gmail.com>
   4  *
   5  * This file is part of FRRouting (FRR).
   6  *
   7  * FRR is free software; you can redistribute it and/or modify it under the
   8  * terms of the GNU General Public License as published by the Free Software
   9  * Foundation; either version 2, or (at your option) any later version.
  10  *
  11  * FRR is distributed in the hope that it will be useful, but WITHOUT ANY
  12  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  13  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  14  * details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include "memory.h"
  22 #include "lib/jhash.h"
  23 #include "frrstr.h"
  24
  25 #include "bgpd/bgpd.h"
  26 #include "bgpd/bgp_community_alias.h"
  27
  28 static struct hash *bgp_ca_alias_hash;
  29 static struct hash *bgp_ca_community_hash;
  30
  31 static unsigned int bgp_ca_community_hash_key(const void *p)
  32 {
  33         const struct community_alias *ca = p;
  34
  35         return jhash(ca->community, sizeof(ca->community), 0);
  36 }
  37
  38 static bool bgp_ca_community_hash_cmp(const void *p1, const void *p2)
  39 {
  40         const struct community_alias *ca1 = p1;
  41         const struct community_alias *ca2 = p2;
  42
  43         return (strncmp(ca1->community, ca2->community,
  44                         sizeof(struct community_alias))
  45                 == 0);
  46 }
  47
  48 static unsigned int bgp_ca_alias_hash_key(const void *p)
  49 {
  50         const struct community_alias *ca = p;
  51
  52         return jhash(ca->alias, sizeof(ca->alias), 0);
  53 }
  54
  55 static bool bgp_ca_alias_hash_cmp(const void *p1, const void *p2)
  56 {
  57         const struct community_alias *ca1 = p1;
  58         const struct community_alias *ca2 = p2;
  59
  60         return (strncmp(ca1->alias, ca2->alias, sizeof(struct community_alias))
  61                 == 0);
  62 }
  63
  64 static void *bgp_community_alias_alloc(void *p)
  65 {
  66         const struct community_alias *ca = p;
  67         struct communtiy_alias *new;
  68
  69         new = XCALLOC(MTYPE_COMMUNITY_ALIAS, sizeof(struct community_alias));
  70         memcpy(new, ca, sizeof(struct community_alias));
  71
  72         return new;
  73 }
  74
  75 void bgp_community_alias_init(void)
  76 {
  77         bgp_ca_community_hash = hash_create(bgp_ca_community_hash_key,
  78                                                bgp_ca_community_hash_cmp,
  79                                                "BGP community alias (community)");
  80         bgp_ca_alias_hash =
  81                 hash_create(bgp_ca_alias_hash_key, bgp_ca_alias_hash_cmp,
  82                             "BGP community alias (alias)");
  83 }
  84
  85 void bgp_community_alias_finish(void)
  86 {
  87         hash_free(bgp_ca_community_hash);
  88         hash_free(bgp_ca_alias_hash);
  89 }
  90
  91 static void bgp_community_alias_show_iterator(struct hash_bucket *hb,
  92                                               struct vty *vty)
  93 {
  94         struct community_alias *ca = hb->data;
  95
  96         vty_out(vty, "bgp community alias %s %s\n", ca->community, ca->alias);
  97 }
  98
  99 int bgp_community_alias_write(struct vty *vty)
 100 {
 101         hash_iterate(bgp_ca_community_hash,
 102                      (void (*)(struct hash_bucket *,
 103                                void *))bgp_community_alias_show_iterator,
 104                      vty);
 105         return 1;
 106 }
 107
 108 void bgp_ca_community_insert(struct community_alias *ca)
 109 {
 110         hash_get(bgp_ca_community_hash, ca, bgp_community_alias_alloc);
 111 }
 112
 113 void bgp_ca_alias_insert(struct community_alias *ca)
 114 {
 115         hash_get(bgp_ca_alias_hash, ca, bgp_community_alias_alloc);
 116 }
 117
 118 void bgp_ca_community_delete(struct community_alias *ca)
 119 {
 120         struct community_alias *data = hash_release(bgp_ca_community_hash, ca);
 121
 122         XFREE(MTYPE_COMMUNITY_ALIAS, data);
 123 }
 124
 125 void bgp_ca_alias_delete(struct community_alias *ca)
 126 {
 127         struct community_alias *data = hash_release(bgp_ca_alias_hash, ca);
 128
 129         XFREE(MTYPE_COMMUNITY_ALIAS, data);
 130 }
 131
 132 struct community_alias *bgp_ca_community_lookup(struct community_alias *ca)
 133 {
 134         return hash_lookup(bgp_ca_community_hash, ca);
 135 }
 136
 137 struct community_alias *bgp_ca_alias_lookup(struct community_alias *ca)
 138 {
 139         return hash_lookup(bgp_ca_alias_hash, ca);
 140 }
 141
 142 const char *bgp_community2alias(char *community)
 143 {
 144         struct community_alias ca;
 145         struct community_alias *find;
 146
 147         memset(&ca, 0, sizeof(ca));
 148         strlcpy(ca.community, community, sizeof(ca.community));
 149
 150         find = bgp_ca_community_lookup(&ca);
 151         if (find)
 152                 return find->alias;
 153
 154         return community;
 155 }
 156
 157 const char *bgp_alias2community(char *alias)
 158 {
 159         struct community_alias ca;
 160         struct community_alias *find;
 161
 162         memset(&ca, 0, sizeof(ca));
 163         strlcpy(ca.alias, alias, sizeof(ca.alias));
 164
 165         find = bgp_ca_alias_lookup(&ca);
 166         if (find)
 167                 return find->community;
 168
 169         return alias;
 170 }
 171
 172 /* Communities structs have `->str` which is used
 173  * for vty outputs and extended BGP community lists
 174  * with regexp.
 175  * This is a helper to convert already aliased version
 176  * of communities into numerical-only format.
 177  */
 178 char *bgp_alias2community_str(const char *str)
 179 {
 180         char **aliases;
 181         char *comstr;
 182         int num, i;
 183
 184         frrstr_split(str, " ", &aliases, &num);
 185         const char *communities[num];
 186
 187         for (i = 0; i < num; i++)
 188                 communities[i] = bgp_alias2community(aliases[i]);
 189
 190         comstr = frrstr_join(communities, num, " ");
 191
 192         for (i = 0; i < num; i++)
 193                 XFREE(MTYPE_TMP, aliases[i]);
 194         XFREE(MTYPE_TMP, aliases);
 195
 196         return comstr;
 197 }
 198
 199 static int bgp_community_alias_vector_walker(struct hash_bucket *bucket,
 200                                              void *data)
 201 {
 202         vector *comps = data;
 203         struct community_alias *alias = bucket->data;
 204
 205         vector_set(*comps, XSTRDUP(MTYPE_COMPLETION, alias->alias));
 206
 207         return 1;
 208 }
 209
 210 static void bgp_community_alias_cmd_completion(vector comps,
 211                                                struct cmd_token *token)
 212 {
 213         hash_walk(bgp_ca_alias_hash, bgp_community_alias_vector_walker, &comps);
 214 }
 215
 216 static const struct cmd_variable_handler community_alias_handlers[] = {
 217         {.varname = "alias_name",
 218          .completions = bgp_community_alias_cmd_completion},
 219         {.tokenname = "ALIAS_NAME",
 220          .completions = bgp_community_alias_cmd_completion},
 221         {.completions = NULL}};
 222
 223 void bgp_community_alias_command_completion_setup(void)
 224 {
 225         cmd_variable_handler_register(community_alias_handlers);
 226 }