bgpd/bgp_label.h

   1 /* BGP carrying Label information
   2  * Copyright (C) 2013 Cumulus Networks, Inc.
   3  *
   4  * This file is part of GNU Zebra.
   5  *
   6  * GNU Zebra 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  * GNU Zebra 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 #ifndef _BGP_LABEL_H
  22 #define _BGP_LABEL_H
  23
  24 #define BGP_LABEL_BYTES 3
  25 #define BGP_LABEL_BITS 24
  26 #define BGP_WITHDRAW_LABEL 0x800000
  27 #define BGP_PREVENT_VRF_2_VRF_LEAK 0xFFFFFFFE
  28
  29 struct bgp_dest;
  30 struct bgp_path_info;
  31 struct peer;
  32
  33 extern int bgp_reg_for_label_callback(mpls_label_t new_label, void *labelid,
  34                                     bool allocated);
  35 extern void bgp_reg_dereg_for_label(struct bgp_dest *dest,
  36                                     struct bgp_path_info *pi, bool reg);
  37 extern int bgp_parse_fec_update(void);
  38 extern mpls_label_t bgp_adv_label(struct bgp_dest *dest,
  39                                   struct bgp_path_info *pi, struct peer *to,
  40                                   afi_t afi, safi_t safi);
  41
  42 extern int bgp_nlri_parse_label(struct peer *peer, struct attr *attr,
  43                                 struct bgp_nlri *packet);
  44
  45 static inline int bgp_labeled_safi(safi_t safi)
  46 {
  47         /* NOTE: This API really says a label (tag) MAY be present. Not all EVPN
  48          * routes will have a label.
  49          */
  50         if ((safi == SAFI_LABELED_UNICAST) || (safi == SAFI_MPLS_VPN)
  51             || (safi == SAFI_EVPN))
  52                 return 1;
  53         return 0;
  54 }
  55
  56 static inline int bgp_is_withdraw_label(mpls_label_t *label)
  57 {
  58         uint8_t *pkt = (uint8_t *)label;
  59
  60         /* The check on pkt[2] for 0x00 or 0x02 is in case bgp_set_valid_label()
  61          * was called on the withdraw label */
  62         if (((pkt[0] == 0x80) || (pkt[0] == 0x00)) && (pkt[1] == 0x00)
  63             && ((pkt[2] == 0x00) || (pkt[2] == 0x02)))
  64                 return 1;
  65         return 0;
  66 }
  67
  68 static inline int bgp_is_valid_label(const mpls_label_t *label)
  69 {
  70         uint8_t *t = (uint8_t *)label;
  71         if (!t)
  72                 return 0;
  73         return (t[2] & 0x02);
  74 }
  75
  76 static inline void bgp_set_valid_label(mpls_label_t *label)
  77 {
  78         uint8_t *t = (uint8_t *)label;
  79         if (t)
  80                 t[2] |= 0x02;
  81 }
  82
  83 static inline void bgp_unset_valid_label(mpls_label_t *label)
  84 {
  85         uint8_t *t = (uint8_t *)label;
  86         if (t)
  87                 t[2] &= ~0x02;
  88 }
  89
  90 static inline void bgp_register_for_label(struct bgp_dest *dest,
  91                                           struct bgp_path_info *pi)
  92 {
  93         bgp_reg_dereg_for_label(dest, pi, true);
  94 }
  95
  96 static inline void bgp_unregister_for_label(struct bgp_dest *dest)
  97 {
  98         bgp_reg_dereg_for_label(dest, NULL, false);
  99 }
 100
 101 /* Return BOS value of label stream */
 102 static inline uint8_t label_bos(mpls_label_t *label)
 103 {
 104         uint8_t *t = (uint8_t *)label;
 105         return (t[2] & 0x01);
 106 };
 107
 108 #endif /* _BGP_LABEL_H */