lib/srv6.h

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * SRv6 definitions
   4  * Copyright (C) 2020  Hiroki Shirokura, LINE Corporation
   5  */
   6
   7 #ifndef _FRR_SRV6_H
   8 #define _FRR_SRV6_H
   9
  10 #include <zebra.h>
  11 #include "prefix.h"
  12 #include "json.h"
  13
  14 #include <arpa/inet.h>
  15 #include <netinet/in.h>
  16
  17 #define SRV6_MAX_SIDS 16
  18 #define SRV6_LOCNAME_SIZE 256
  19
  20 #ifdef __cplusplus
  21 extern "C" {
  22 #endif
  23
  24 #define sid2str(sid, str, size) \
  25         inet_ntop(AF_INET6, sid, str, size)
  26
  27 enum seg6_mode_t {
  28         INLINE,
  29         ENCAP,
  30         L2ENCAP,
  31 };
  32
  33 enum seg6local_action_t {
  34         ZEBRA_SEG6_LOCAL_ACTION_UNSPEC       = 0,
  35         ZEBRA_SEG6_LOCAL_ACTION_END          = 1,
  36         ZEBRA_SEG6_LOCAL_ACTION_END_X        = 2,
  37         ZEBRA_SEG6_LOCAL_ACTION_END_T        = 3,
  38         ZEBRA_SEG6_LOCAL_ACTION_END_DX2      = 4,
  39         ZEBRA_SEG6_LOCAL_ACTION_END_DX6      = 5,
  40         ZEBRA_SEG6_LOCAL_ACTION_END_DX4      = 6,
  41         ZEBRA_SEG6_LOCAL_ACTION_END_DT6      = 7,
  42         ZEBRA_SEG6_LOCAL_ACTION_END_DT4      = 8,
  43         ZEBRA_SEG6_LOCAL_ACTION_END_B6       = 9,
  44         ZEBRA_SEG6_LOCAL_ACTION_END_B6_ENCAP = 10,
  45         ZEBRA_SEG6_LOCAL_ACTION_END_BM       = 11,
  46         ZEBRA_SEG6_LOCAL_ACTION_END_S        = 12,
  47         ZEBRA_SEG6_LOCAL_ACTION_END_AS       = 13,
  48         ZEBRA_SEG6_LOCAL_ACTION_END_AM       = 14,
  49         ZEBRA_SEG6_LOCAL_ACTION_END_BPF      = 15,
  50         ZEBRA_SEG6_LOCAL_ACTION_END_DT46     = 16,
  51 };
  52
  53 struct seg6_segs {
  54         size_t num_segs;
  55         struct in6_addr segs[256];
  56 };
  57
  58 struct seg6local_context {
  59         struct in_addr nh4;
  60         struct in6_addr nh6;
  61         uint32_t table;
  62 };
  63
  64 struct srv6_locator {
  65         char name[SRV6_LOCNAME_SIZE];
  66         struct prefix_ipv6 prefix;
  67
  68         /*
  69          * Bit length of SRv6 locator described in
  70          * draft-ietf-bess-srv6-services-05#section-3.2.1
  71          */
  72         uint8_t block_bits_length;
  73         uint8_t node_bits_length;
  74         uint8_t function_bits_length;
  75         uint8_t argument_bits_length;
  76
  77         int algonum;
  78         uint64_t current;
  79         bool status_up;
  80         struct list *chunks;
  81
  82         uint8_t flags;
  83 #define SRV6_LOCATOR_USID (1 << 0) /* The SRv6 Locator is a uSID Locator */
  84
  85         QOBJ_FIELDS;
  86 };
  87 DECLARE_QOBJ_TYPE(srv6_locator);
  88
  89 struct srv6_locator_chunk {
  90         char locator_name[SRV6_LOCNAME_SIZE];
  91         struct prefix_ipv6 prefix;
  92
  93         /*
  94          * Bit length of SRv6 locator described in
  95          * draft-ietf-bess-srv6-services-05#section-3.2.1
  96          */
  97         uint8_t block_bits_length;
  98         uint8_t node_bits_length;
  99         uint8_t function_bits_length;
 100         uint8_t argument_bits_length;
 101
 102         /*
 103          * For Zclient communication values
 104          */
 105         uint8_t keep;
 106         uint8_t proto;
 107         uint16_t instance;
 108         uint32_t session_id;
 109
 110         uint8_t flags;
 111 };
 112
 113 /*
 114  * SRv6 Endpoint Behavior codepoints, as defined by IANA in
 115  * https://www.iana.org/assignments/segment-routing/segment-routing.xhtml
 116  */
 117 enum srv6_endpoint_behavior_codepoint {
 118         SRV6_ENDPOINT_BEHAVIOR_RESERVED       = 0x0000,
 119         SRV6_ENDPOINT_BEHAVIOR_END_DT6        = 0x0012,
 120         SRV6_ENDPOINT_BEHAVIOR_END_DT4        = 0x0013,
 121         SRV6_ENDPOINT_BEHAVIOR_END_DT46       = 0x0014,
 122         SRV6_ENDPOINT_BEHAVIOR_END_DT6_USID   = 0x003E,
 123         SRV6_ENDPOINT_BEHAVIOR_END_DT4_USID   = 0x003F,
 124         SRV6_ENDPOINT_BEHAVIOR_END_DT46_USID  = 0x0040,
 125         SRV6_ENDPOINT_BEHAVIOR_OPAQUE         = 0xFFFF,
 126 };
 127
 128 struct nexthop_srv6 {
 129         /* SRv6 localsid info for Endpoint-behaviour */
 130         enum seg6local_action_t seg6local_action;
 131         struct seg6local_context seg6local_ctx;
 132
 133         /* SRv6 Headend-behaviour */
 134         struct in6_addr seg6_segs;
 135 };
 136
 137 static inline const char *seg6_mode2str(enum seg6_mode_t mode)
 138 {
 139         switch (mode) {
 140         case INLINE:
 141                 return "INLINE";
 142         case ENCAP:
 143                 return "ENCAP";
 144         case L2ENCAP:
 145                 return "L2ENCAP";
 146         default:
 147                 return "unknown";
 148         }
 149 }
 150
 151 static inline bool sid_same(
 152                 const struct in6_addr *a,
 153                 const struct in6_addr *b)
 154 {
 155         if (!a && !b)
 156                 return true;
 157         else if (!(a && b))
 158                 return false;
 159         else
 160                 return memcmp(a, b, sizeof(struct in6_addr)) == 0;
 161 }
 162
 163 static inline bool sid_diff(
 164                 const struct in6_addr *a,
 165                 const struct in6_addr *b)
 166 {
 167         return !sid_same(a, b);
 168 }
 169
 170 static inline bool sid_zero(
 171                 const struct in6_addr *a)
 172 {
 173         struct in6_addr zero = {};
 174
 175         return sid_same(a, &zero);
 176 }
 177
 178 static inline void *sid_copy(struct in6_addr *dst,
 179                 const struct in6_addr *src)
 180 {
 181         return memcpy(dst, src, sizeof(struct in6_addr));
 182 }
 183
 184 const char *
 185 seg6local_action2str(uint32_t action);
 186
 187 const char *seg6local_context2str(char *str, size_t size,
 188                                   const struct seg6local_context *ctx,
 189                                   uint32_t action);
 190
 191 int snprintf_seg6_segs(char *str,
 192                 size_t size, const struct seg6_segs *segs);
 193
 194 extern struct srv6_locator *srv6_locator_alloc(const char *name);
 195 extern struct srv6_locator_chunk *srv6_locator_chunk_alloc(void);
 196 extern void srv6_locator_free(struct srv6_locator *locator);
 197 extern void srv6_locator_chunk_free(struct srv6_locator_chunk **chunk);
 198 json_object *srv6_locator_chunk_json(const struct srv6_locator_chunk *chunk);
 199 json_object *srv6_locator_json(const struct srv6_locator *loc);
 200 json_object *srv6_locator_detailed_json(const struct srv6_locator *loc);
 201 json_object *
 202 srv6_locator_chunk_detailed_json(const struct srv6_locator_chunk *chunk);
 203
 204 #ifdef __cplusplus
 205 }
 206 #endif
 207
 208 #endif