bgpd/bgp_attr_evpn.c

   1 /* Ethernet-VPN Attribute handling file
   2  * Copyright (C) 2016 6WIND
   3  *
   4  * This file is part of FRRouting.
   5  *
   6  * FRRouting is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2, or (at your option) any
   9  * later version.
  10  *
  11  * FRRouting 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 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 <zebra.h>
  22
  23 #include "command.h"
  24 #include "filter.h"
  25 #include "prefix.h"
  26 #include "log.h"
  27 #include "memory.h"
  28 #include "stream.h"
  29
  30 #include "bgpd/bgpd.h"
  31 #include "bgpd/bgp_attr.h"
  32 #include "bgpd/bgp_route.h"
  33 #include "bgpd/bgp_attr_evpn.h"
  34 #include "bgpd/bgp_ecommunity.h"
  35 #include "bgpd/bgp_evpn.h"
  36 #include "bgpd/bgp_evpn_private.h"
  37
  38 void bgp_add_routermac_ecom(struct attr *attr, struct ethaddr *routermac)
  39 {
  40         struct ecommunity_val routermac_ecom;
  41
  42         memset(&routermac_ecom, 0, sizeof(struct ecommunity_val));
  43         routermac_ecom.val[0] = ECOMMUNITY_ENCODE_EVPN;
  44         routermac_ecom.val[1] = ECOMMUNITY_EVPN_SUBTYPE_ROUTERMAC;
  45         memcpy(&routermac_ecom.val[2], routermac->octet, ETH_ALEN);
  46         if (!attr->ecommunity)
  47                 attr->ecommunity = ecommunity_new();
  48         ecommunity_add_val(attr->ecommunity, &routermac_ecom);
  49         ecommunity_str(attr->ecommunity);
  50 }
  51
  52 /* converts to an esi
  53  * returns 1 on success, 0 otherwise
  54  * format accepted: AA:BB:CC:DD:EE:FF:GG:HH:II:JJ
  55  * if id is null, check only is done
  56  */
  57 int str2esi(const char *str, struct eth_segment_id *id)
  58 {
  59         unsigned int a[ESI_LEN];
  60         int i;
  61
  62         if (!str)
  63                 return 0;
  64         if (sscanf(str, "%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x", a + 0, a + 1,
  65                    a + 2, a + 3, a + 4, a + 5, a + 6, a + 7, a + 8, a + 9)
  66             != ESI_LEN) {
  67                 /* error in incoming str length */
  68                 return 0;
  69         }
  70         /* valid mac address */
  71         if (!id)
  72                 return 1;
  73         for (i = 0; i < ESI_LEN; ++i)
  74                 id->val[i] = a[i] & 0xff;
  75         return 1;
  76 }
  77
  78 char *esi2str(struct eth_segment_id *id)
  79 {
  80         char *ptr;
  81         u_char *val;
  82
  83         if (!id)
  84                 return NULL;
  85
  86         val = id->val;
  87         ptr = (char *)XMALLOC(MTYPE_TMP,
  88                               (ESI_LEN * 2 + ESI_LEN - 1 + 1) * sizeof(char));
  89
  90         snprintf(ptr, (ESI_LEN * 2 + ESI_LEN - 1 + 1),
  91                  "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x", val[0],
  92                  val[1], val[2], val[3], val[4], val[5], val[6], val[7], val[8],
  93                  val[9]);
  94
  95         return ptr;
  96 }
  97
  98 char *ecom_mac2str(char *ecom_mac)
  99 {
 100         char *en;
 101
 102         en = ecom_mac;
 103         en += 2;
 104
 105         return prefix_mac2str((struct ethaddr *)en, NULL, 0);
 106 }
 107
 108 /* Fetch router-mac from extended community */
 109 void bgp_attr_rmac(struct attr *attr,
 110                    struct ethaddr *rmac)
 111 {
 112         int i = 0;
 113         struct ecommunity *ecom;
 114
 115         ecom = attr->ecommunity;
 116         if (!ecom || !ecom->size)
 117                 return;
 118
 119         /* If there is a router mac extended community, set RMAC in attr */
 120         for (i = 0; i < ecom->size; i++) {
 121                 u_char *pnt = NULL;
 122                 u_char type = 0;
 123                 u_char sub_type = 0;
 124
 125                 pnt = (ecom->val + (i * ECOMMUNITY_SIZE));
 126                 type = *pnt++;
 127                 sub_type = *pnt++;
 128
 129                 if (!(type == ECOMMUNITY_ENCODE_EVPN &&
 130                      sub_type == ECOMMUNITY_EVPN_SUBTYPE_ROUTERMAC))
 131                         continue;
 132
 133                 memcpy(rmac, pnt, ETH_ALEN);
 134         }
 135 }
 136
 137 /*
 138  * return true if attr contains default gw extended community
 139  */
 140 uint8_t bgp_attr_default_gw(struct attr *attr)
 141 {
 142         struct ecommunity       *ecom;
 143         int                     i;
 144
 145         ecom = attr->ecommunity;
 146         if (!ecom || !ecom->size)
 147                 return 0;
 148
 149         /* If there is a default gw extendd community return true otherwise
 150          * return 0 */
 151         for (i = 0; i < ecom->size; i++) {
 152                 u_char          *pnt;
 153                 u_char          type, sub_type;
 154
 155                 pnt = (ecom->val + (i * ECOMMUNITY_SIZE));
 156                 type = *pnt++;
 157                 sub_type = *pnt++;
 158
 159                 if ((type == ECOMMUNITY_ENCODE_OPAQUE
 160                       && sub_type == ECOMMUNITY_EVPN_SUBTYPE_DEF_GW))
 161                         return 1;
 162         }
 163
 164         return 0;
 165 }
 166
 167 /*
 168  * Fetch and return the sequence number from MAC Mobility extended
 169  * community, if present, else 0.
 170  */
 171 u_int32_t bgp_attr_mac_mobility_seqnum(struct attr *attr, u_char *sticky)
 172 {
 173         struct ecommunity *ecom;
 174         int i;
 175         u_char flags = 0;
 176
 177         ecom = attr->ecommunity;
 178         if (!ecom || !ecom->size)
 179                 return 0;
 180
 181         /* If there is a MAC Mobility extended community, return its
 182          * sequence number.
 183          * TODO: RFC is silent on handling of multiple MAC mobility extended
 184          * communities for the same route. We will bail out upon the first
 185          * one.
 186          */
 187         for (i = 0; i < ecom->size; i++) {
 188                 u_char *pnt;
 189                 u_char type, sub_type;
 190                 u_int32_t seq_num;
 191
 192                 pnt = (ecom->val + (i * ECOMMUNITY_SIZE));
 193                 type = *pnt++;
 194                 sub_type = *pnt++;
 195                 if (!(type == ECOMMUNITY_ENCODE_EVPN
 196                       && sub_type == ECOMMUNITY_EVPN_SUBTYPE_MACMOBILITY))
 197                         continue;
 198                 flags = *pnt++;
 199
 200                 if (flags & ECOMMUNITY_EVPN_SUBTYPE_MACMOBILITY_FLAG_STICKY)
 201                         *sticky = 1;
 202                 else
 203                         *sticky = 0;
 204
 205                 pnt++;
 206                 pnt = ptr_get_be32(pnt, &seq_num);
 207                 (void)pnt; /* consume value */
 208                 return seq_num;
 209         }
 210
 211         return 0;
 212 }
 213
 214 /* dst prefix must be AF_INET or AF_INET6 prefix, to forge EVPN prefix */
 215 extern int bgp_build_evpn_prefix(int evpn_type, uint32_t eth_tag,
 216                                  struct prefix *dst)
 217 {
 218         struct evpn_addr *p_evpn_p;
 219         struct prefix p2;
 220         struct prefix *src = &p2;
 221
 222         if (!dst || dst->family == 0)
 223                 return -1;
 224         /* store initial prefix in src */
 225         prefix_copy(src, dst);
 226         memset(dst, 0, sizeof(struct prefix));
 227         p_evpn_p = &(dst->u.prefix_evpn);
 228         dst->family = AF_EVPN;
 229         p_evpn_p->route_type = evpn_type;
 230         if (evpn_type == BGP_EVPN_IP_PREFIX_ROUTE) {
 231                 p_evpn_p->eth_tag = eth_tag;
 232                 p_evpn_p->ip_prefix_length = p2.prefixlen;
 233                 if (src->family == AF_INET) {
 234                         SET_IPADDR_V4(&p_evpn_p->ip);
 235                         memcpy(&p_evpn_p->ip.ipaddr_v4, &src->u.prefix4,
 236                                sizeof(struct in_addr));
 237                         dst->prefixlen = (u_char)PREFIX_LEN_ROUTE_TYPE_5_IPV4;
 238                 } else {
 239                         SET_IPADDR_V6(&p_evpn_p->ip);
 240                         memcpy(&p_evpn_p->ip.ipaddr_v6, &src->u.prefix6,
 241                                sizeof(struct in6_addr));
 242                         dst->prefixlen = (u_char)PREFIX_LEN_ROUTE_TYPE_5_IPV6;
 243                 }
 244         } else
 245                 return -1;
 246         return 0;
 247 }