lib/srv6.h

   1 /*
   2  * SRv6 definitions
   3  * Copyright (C) 2020  Hiroki Shirokura, LINE Corporation
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the Free
   7  * Software Foundation; either version 2 of the License, or (at your option)
   8  * any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * 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 #ifndef _FRR_SRV6_H
  21 #define _FRR_SRV6_H
  22
  23 #include <zebra.h>
  24 #include "prefix.h"
  25 #include "json.h"
  26
  27 #include <arpa/inet.h>
  28 #include <netinet/in.h>
  29
  30 #define SRV6_MAX_SIDS 16
  31 #define SRV6_LOCNAME_SIZE 256
  32
  33 #ifdef __cplusplus
  34 extern "C" {
  35 #endif
  36
  37 #define sid2str(sid, str, size) \
  38         inet_ntop(AF_INET6, sid, str, size)
  39
  40 enum seg6_mode_t {
  41         INLINE,
  42         ENCAP,
  43         L2ENCAP,
  44 };
  45
  46 enum seg6local_action_t {
  47         ZEBRA_SEG6_LOCAL_ACTION_UNSPEC       = 0,
  48         ZEBRA_SEG6_LOCAL_ACTION_END          = 1,
  49         ZEBRA_SEG6_LOCAL_ACTION_END_X        = 2,
  50         ZEBRA_SEG6_LOCAL_ACTION_END_T        = 3,
  51         ZEBRA_SEG6_LOCAL_ACTION_END_DX2      = 4,
  52         ZEBRA_SEG6_LOCAL_ACTION_END_DX6      = 5,
  53         ZEBRA_SEG6_LOCAL_ACTION_END_DX4      = 6,
  54         ZEBRA_SEG6_LOCAL_ACTION_END_DT6      = 7,
  55         ZEBRA_SEG6_LOCAL_ACTION_END_DT4      = 8,
  56         ZEBRA_SEG6_LOCAL_ACTION_END_B6       = 9,
  57         ZEBRA_SEG6_LOCAL_ACTION_END_B6_ENCAP = 10,
  58         ZEBRA_SEG6_LOCAL_ACTION_END_BM       = 11,
  59         ZEBRA_SEG6_LOCAL_ACTION_END_S        = 12,
  60         ZEBRA_SEG6_LOCAL_ACTION_END_AS       = 13,
  61         ZEBRA_SEG6_LOCAL_ACTION_END_AM       = 14,
  62         ZEBRA_SEG6_LOCAL_ACTION_END_BPF      = 15,
  63         ZEBRA_SEG6_LOCAL_ACTION_END_DT46     = 16,
  64 };
  65
  66 struct seg6_segs {
  67         size_t num_segs;
  68         struct in6_addr segs[256];
  69 };
  70
  71 struct seg6local_context {
  72         struct in_addr nh4;
  73         struct in6_addr nh6;
  74         uint32_t table;
  75 };
  76
  77 struct srv6_locator {
  78         char name[SRV6_LOCNAME_SIZE];
  79         struct prefix_ipv6 prefix;
  80
  81         /*
  82          * Bit length of SRv6 locator described in
  83          * draft-ietf-bess-srv6-services-05#section-3.2.1
  84          */
  85         uint8_t block_bits_length;
  86         uint8_t node_bits_length;
  87         uint8_t function_bits_length;
  88         uint8_t argument_bits_length;
  89
  90         int algonum;
  91         uint64_t current;
  92         bool status_up;
  93         struct list *chunks;
  94
  95         uint8_t flags;
  96 #define SRV6_LOCATOR_USID (1 << 0) /* The SRv6 Locator is a uSID Locator */
  97
  98         QOBJ_FIELDS;
  99 };
 100 DECLARE_QOBJ_TYPE(srv6_locator);
 101
 102 struct srv6_locator_chunk {
 103         char locator_name[SRV6_LOCNAME_SIZE];
 104         struct prefix_ipv6 prefix;
 105
 106         /*
 107          * Bit length of SRv6 locator described in
 108          * draft-ietf-bess-srv6-services-05#section-3.2.1
 109          */
 110         uint8_t block_bits_length;
 111         uint8_t node_bits_length;
 112         uint8_t function_bits_length;
 113         uint8_t argument_bits_length;
 114
 115         /*
 116          * For Zclient communication values
 117          */
 118         uint8_t keep;
 119         uint8_t proto;
 120         uint16_t instance;
 121         uint32_t session_id;
 122
 123         uint8_t flags;
 124 };
 125
 126 /*
 127  * SRv6 Endpoint Behavior codepoints, as defined by IANA in
 128  * https://www.iana.org/assignments/segment-routing/segment-routing.xhtml
 129  */
 130 enum srv6_endpoint_behavior_codepoint {
 131         SRV6_ENDPOINT_BEHAVIOR_RESERVED       = 0x0000,
 132         SRV6_ENDPOINT_BEHAVIOR_END_DT6        = 0x0012,
 133         SRV6_ENDPOINT_BEHAVIOR_END_DT4        = 0x0013,
 134         SRV6_ENDPOINT_BEHAVIOR_END_DT46       = 0x0014,
 135         SRV6_ENDPOINT_BEHAVIOR_END_DT6_USID   = 0x003E,
 136         SRV6_ENDPOINT_BEHAVIOR_END_DT4_USID   = 0x003F,
 137         SRV6_ENDPOINT_BEHAVIOR_END_DT46_USID  = 0x0040,
 138         SRV6_ENDPOINT_BEHAVIOR_OPAQUE         = 0xFFFF,
 139 };
 140
 141 struct nexthop_srv6 {
 142         /* SRv6 localsid info for Endpoint-behaviour */
 143         enum seg6local_action_t seg6local_action;
 144         struct seg6local_context seg6local_ctx;
 145
 146         /* SRv6 Headend-behaviour */
 147         struct in6_addr seg6_segs;
 148 };
 149
 150 static inline const char *seg6_mode2str(enum seg6_mode_t mode)
 151 {
 152         switch (mode) {
 153         case INLINE:
 154                 return "INLINE";
 155         case ENCAP:
 156                 return "ENCAP";
 157         case L2ENCAP:
 158                 return "L2ENCAP";
 159         default:
 160                 return "unknown";
 161         }
 162 }
 163
 164 static inline bool sid_same(
 165                 const struct in6_addr *a,
 166                 const struct in6_addr *b)
 167 {
 168         if (!a && !b)
 169                 return true;
 170         else if (!(a && b))
 171                 return false;
 172         else
 173                 return memcmp(a, b, sizeof(struct in6_addr)) == 0;
 174 }
 175
 176 static inline bool sid_diff(
 177                 const struct in6_addr *a,
 178                 const struct in6_addr *b)
 179 {
 180         return !sid_same(a, b);
 181 }
 182
 183 static inline bool sid_zero(
 184                 const struct in6_addr *a)
 185 {
 186         struct in6_addr zero = {};
 187
 188         return sid_same(a, &zero);
 189 }
 190
 191 static inline void *sid_copy(struct in6_addr *dst,
 192                 const struct in6_addr *src)
 193 {
 194         return memcpy(dst, src, sizeof(struct in6_addr));
 195 }
 196
 197 const char *
 198 seg6local_action2str(uint32_t action);
 199
 200 const char *seg6local_context2str(char *str, size_t size,
 201                                   const struct seg6local_context *ctx,
 202                                   uint32_t action);
 203
 204 int snprintf_seg6_segs(char *str,
 205                 size_t size, const struct seg6_segs *segs);
 206
 207 extern struct srv6_locator *srv6_locator_alloc(const char *name);
 208 extern struct srv6_locator_chunk *srv6_locator_chunk_alloc(void);
 209 extern void srv6_locator_free(struct srv6_locator *locator);
 210 extern void srv6_locator_chunk_free(struct srv6_locator_chunk **chunk);
 211 json_object *srv6_locator_chunk_json(const struct srv6_locator_chunk *chunk);
 212 json_object *srv6_locator_json(const struct srv6_locator *loc);
 213 json_object *srv6_locator_detailed_json(const struct srv6_locator *loc);
 214 json_object *
 215 srv6_locator_chunk_detailed_json(const struct srv6_locator_chunk *chunk);
 216
 217 #ifdef __cplusplus
 218 }
 219 #endif
 220
 221 #endif