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
  28 struct bgp_node;
  29 struct bgp_info;
  30 struct peer;
  31
  32 extern void bgp_reg_dereg_for_label (struct bgp_node *rn, struct bgp_info *ri,
  33                                      int reg);
  34 extern int bgp_parse_fec_update(void);
  35 extern u_char * bgp_adv_label(struct bgp_node *rn, struct bgp_info *ri,
  36                               struct peer *to, afi_t afi, safi_t safi);
  37
  38 extern int bgp_nlri_parse_label (struct peer *peer, struct attr *attr,
  39                                  struct bgp_nlri *packet);
  40
  41 static inline int
  42 bgp_labeled_safi (safi_t safi)
  43 {
  44   if ((safi == SAFI_LABELED_UNICAST) || (safi == SAFI_MPLS_VPN) ||
  45       (safi == SAFI_EVPN))
  46     return 1;
  47   return 0;
  48 }
  49
  50 static inline int
  51 bgp_is_withdraw_label (u_char *pkt)
  52 {
  53   if ((pkt[0] == 0x80) && (pkt[1] == 0x00) && (pkt[2] == 0x00))
  54       return 1;
  55   return 0;
  56 }
  57
  58 static inline u_char *
  59 bgp_encode_withdraw_label (u_char *pkt)
  60 {
  61   *pkt++ = 0x80; *pkt++ = 0x00; *pkt++ = 0x00;
  62   return pkt;
  63 }
  64
  65 static inline int
  66 bgp_is_valid_label (u_char *t)
  67 {
  68   if (!t)
  69     return 0;
  70   return (t[2] & 0x02);
  71 }
  72
  73 static inline void
  74 bgp_set_valid_label (u_char *t)
  75 {
  76   if (t)
  77     t[2] |= 0x02;
  78 }
  79
  80 static inline void
  81 bgp_unset_valid_label (u_char *t)
  82 {
  83   if (t)
  84     t[2] &= ~0x02;
  85 }
  86
  87 static inline void
  88 bgp_register_for_label (struct bgp_node *rn, struct bgp_info *ri)
  89 {
  90   bgp_reg_dereg_for_label (rn, ri, 1);
  91 }
  92
  93 static inline void
  94 bgp_unregister_for_label (struct bgp_node *rn)
  95 {
  96   bgp_reg_dereg_for_label (rn, NULL, 0);
  97 }
  98
  99 /* Label stream to value */
 100 static inline u_int32_t
 101 label_pton (u_char t[])
 102 {
 103   return ((((unsigned int) t[0]) << 12) | (((unsigned int) t[1]) << 4) |
 104          ((unsigned int) ((t[2] & 0xF0) >> 4)));
 105 }
 106
 107 /* Encode label values */
 108 static inline void
 109 label_ntop (u_int32_t l, int bos, u_char t[])
 110 {
 111   t[0] = ((l & 0x000FF000) >> 12);
 112   t[1] = ((l & 0x00000FF0) >> 4);
 113   t[2] = ((l & 0x0000000F) << 4);
 114   if (bos)
 115     t[2] |= 0x01;
 116 }
 117
 118 /* Return BOS value of label stream */
 119 static inline u_char
 120 label_bos (u_char t[])
 121 {
 122   return (t[2] & 0x01);
 123 };
 124
 125 #endif /* _BGP_LABEL_H */