lib/nexthop.h

   1 /*
   2  * Nexthop structure definition.
   3  * Copyright (C) 1997, 98, 99, 2001 Kunihiro Ishiguro
   4  * Copyright (C) 2013 Cumulus Networks, Inc.
   5  *
   6  * This file is part of Quagga.
   7  *
   8  * Quagga is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2, or (at your option) any
  11  * later version.
  12  *
  13  * Quagga is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; see the file COPYING; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #ifndef _LIB_NEXTHOP_H
  24 #define _LIB_NEXTHOP_H
  25
  26 #include "prefix.h"
  27 #include "mpls.h"
  28 #include "vxlan.h"
  29 #include "srv6.h"
  30
  31 #ifdef __cplusplus
  32 extern "C" {
  33 #endif
  34
  35 /* Maximum next hop string length - gateway + ifindex */
  36 #define NEXTHOP_STRLEN (INET6_ADDRSTRLEN + 30)
  37
  38 union g_addr {
  39         struct in_addr ipv4;
  40         struct in6_addr ipv6;
  41 };
  42
  43 enum nexthop_types_t {
  44         NEXTHOP_TYPE_IFINDEX = 1,  /* Directly connected.  */
  45         NEXTHOP_TYPE_IPV4,       /* IPv4 nexthop.  */
  46         NEXTHOP_TYPE_IPV4_IFINDEX, /* IPv4 nexthop with ifindex.  */
  47         NEXTHOP_TYPE_IPV6,       /* IPv6 nexthop.  */
  48         NEXTHOP_TYPE_IPV6_IFINDEX, /* IPv6 nexthop with ifindex.  */
  49         NEXTHOP_TYPE_BLACKHOLE,    /* Null0 nexthop.  */
  50 };
  51
  52 enum blackhole_type {
  53         BLACKHOLE_UNSPEC = 0,
  54         BLACKHOLE_NULL,
  55         BLACKHOLE_REJECT,
  56         BLACKHOLE_ADMINPROHIB,
  57 };
  58
  59 enum nh_encap_type {
  60         NET_VXLAN = 100, /* value copied from FPM_NH_ENCAP_VXLAN. */
  61 };
  62
  63 /* Fixed limit on the number of backup nexthops per primary nexthop */
  64 #define NEXTHOP_MAX_BACKUPS  8
  65
  66 /* Backup index value is limited */
  67 #define NEXTHOP_BACKUP_IDX_MAX 255
  68
  69 /* Nexthop structure. */
  70 struct nexthop {
  71         struct nexthop *next;
  72         struct nexthop *prev;
  73
  74         /*
  75          * What vrf is this nexthop associated with?
  76          */
  77         vrf_id_t vrf_id;
  78
  79         /* Interface index. */
  80         ifindex_t ifindex;
  81
  82         enum nexthop_types_t type;
  83
  84         uint16_t flags;
  85 #define NEXTHOP_FLAG_ACTIVE     (1 << 0) /* This nexthop is alive. */
  86 #define NEXTHOP_FLAG_FIB        (1 << 1) /* FIB nexthop. */
  87 #define NEXTHOP_FLAG_RECURSIVE  (1 << 2) /* Recursive nexthop. */
  88 #define NEXTHOP_FLAG_ONLINK     (1 << 3) /* Nexthop should be installed
  89                                           * onlink.
  90                                           */
  91 #define NEXTHOP_FLAG_DUPLICATE  (1 << 4) /* nexthop duplicates another
  92                                           * active one
  93                                           */
  94 #define NEXTHOP_FLAG_RNH_FILTERED  (1 << 5) /* rmap filtered, used by rnh */
  95 #define NEXTHOP_FLAG_HAS_BACKUP (1 << 6)    /* Backup nexthop index is set */
  96 #define NEXTHOP_FLAG_SRTE       (1 << 7) /* SR-TE color used for BGP traffic */
  97 #define NEXTHOP_FLAG_EVPN       (1 << 8) /* nexthop is EVPN */
  98 #define NEXTHOP_FLAG_LINKDOWN   (1 << 9) /* is not removed on link down */
  99
 100 #define NEXTHOP_IS_ACTIVE(flags)                                               \
 101         (CHECK_FLAG(flags, NEXTHOP_FLAG_ACTIVE)                                \
 102          && !CHECK_FLAG(flags, NEXTHOP_FLAG_DUPLICATE))
 103
 104         /* Nexthop address */
 105         union {
 106                 union g_addr gate;
 107                 enum blackhole_type bh_type;
 108         };
 109         union g_addr src;
 110         union g_addr rmap_src; /* Src is set via routemap */
 111
 112         /* Nexthops obtained by recursive resolution.
 113          *
 114          * If the nexthop struct needs to be resolved recursively,
 115          * NEXTHOP_FLAG_RECURSIVE will be set in flags and the nexthops
 116          * obtained by recursive resolution will be added to `resolved'.
 117          */
 118         struct nexthop *resolved;
 119         /* Recursive parent */
 120         struct nexthop *rparent;
 121
 122         /* Type of label(s), if any */
 123         enum lsp_types_t nh_label_type;
 124
 125         /* Label(s) associated with this nexthop. */
 126         struct mpls_label_stack *nh_label;
 127
 128         /* Weight of the nexthop ( for unequal cost ECMP ) */
 129         uint8_t weight;
 130
 131         /* Count and index of corresponding backup nexthop(s) in a backup list;
 132          * only meaningful if the HAS_BACKUP flag is set.
 133          */
 134         uint8_t backup_num;
 135         uint8_t backup_idx[NEXTHOP_MAX_BACKUPS];
 136
 137         /* Encapsulation information. */
 138         enum nh_encap_type nh_encap_type;
 139         union {
 140                 vni_t vni;
 141         } nh_encap;
 142
 143         /* SR-TE color used for matching SR-TE policies */
 144         uint32_t srte_color;
 145
 146         /* SRv6 information */
 147         struct nexthop_srv6 *nh_srv6;
 148 };
 149
 150 /* Utility to append one nexthop to another. */
 151 #define NEXTHOP_APPEND(to, new)           \
 152         do {                              \
 153                 (to)->next = (new);       \
 154                 (new)->prev = (to);       \
 155                 (new)->next = NULL;       \
 156         } while (0)
 157
 158 struct nexthop *nexthop_new(void);
 159
 160 void nexthop_free(struct nexthop *nexthop);
 161 void nexthops_free(struct nexthop *nexthop);
 162
 163 void nexthop_add_labels(struct nexthop *nexthop, enum lsp_types_t ltype,
 164                         uint8_t num_labels, const mpls_label_t *labels);
 165 void nexthop_del_labels(struct nexthop *);
 166 void nexthop_add_srv6_seg6local(struct nexthop *nexthop, uint32_t action,
 167                                 const struct seg6local_context *ctx);
 168 void nexthop_del_srv6_seg6local(struct nexthop *nexthop);
 169 void nexthop_add_srv6_seg6(struct nexthop *nexthop,
 170                            const struct in6_addr *segs);
 171 void nexthop_del_srv6_seg6(struct nexthop *nexthop);
 172
 173 /*
 174  * Allocate a new nexthop object and initialize it from various args.
 175  */
 176 struct nexthop *nexthop_from_ifindex(ifindex_t ifindex, vrf_id_t vrf_id);
 177 struct nexthop *nexthop_from_ipv4(const struct in_addr *ipv4,
 178                                   const struct in_addr *src,
 179                                   vrf_id_t vrf_id);
 180 struct nexthop *nexthop_from_ipv4_ifindex(const struct in_addr *ipv4,
 181                                           const struct in_addr *src,
 182                                           ifindex_t ifindex, vrf_id_t vrf_id);
 183 struct nexthop *nexthop_from_ipv6(const struct in6_addr *ipv6,
 184                                   vrf_id_t vrf_id);
 185 struct nexthop *nexthop_from_ipv6_ifindex(const struct in6_addr *ipv6,
 186                                           ifindex_t ifindex, vrf_id_t vrf_id);
 187 struct nexthop *nexthop_from_blackhole(enum blackhole_type bh_type,
 188                                        vrf_id_t nh_vrf_id);
 189
 190 /*
 191  * Hash a nexthop. Suitable for use with hash tables.
 192  *
 193  * This function uses the following values when computing the hash:
 194  * - vrf_id
 195  * - ifindex
 196  * - type
 197  * - gate
 198  *
 199  * nexthop
 200  *    The nexthop to hash
 201  *
 202  * Returns:
 203  *    32-bit hash of nexthop
 204  */
 205 uint32_t nexthop_hash(const struct nexthop *nexthop);
 206 /*
 207  * Hash a nexthop only on word-sized attributes:
 208  * - vrf_id
 209  * - ifindex
 210  * - type
 211  * - (some) flags
 212  */
 213 uint32_t nexthop_hash_quick(const struct nexthop *nexthop);
 214
 215 extern bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2);
 216 extern bool nexthop_same_no_labels(const struct nexthop *nh1,
 217                                    const struct nexthop *nh2);
 218 extern int nexthop_cmp(const struct nexthop *nh1, const struct nexthop *nh2);
 219 extern int nexthop_g_addr_cmp(enum nexthop_types_t type,
 220                               const union g_addr *addr1,
 221                               const union g_addr *addr2);
 222
 223 /* More-limited comparison function used to detect duplicate nexthops.
 224  * Returns -1, 0, 1
 225  */
 226 int nexthop_cmp_basic(const struct nexthop *nh1, const struct nexthop *nh2);
 227
 228 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 229 extern bool nexthop_labels_match(const struct nexthop *nh1,
 230                                  const struct nexthop *nh2);
 231
 232 extern const char *nexthop2str(const struct nexthop *nexthop,
 233                                char *str, int size);
 234 extern struct nexthop *nexthop_next(const struct nexthop *nexthop);
 235 extern struct nexthop *
 236 nexthop_next_active_resolved(const struct nexthop *nexthop);
 237 extern unsigned int nexthop_level(const struct nexthop *nexthop);
 238 /* Copies to an already allocated nexthop struct */
 239 extern void nexthop_copy(struct nexthop *copy, const struct nexthop *nexthop,
 240                          struct nexthop *rparent);
 241 /* Copies to an already allocated nexthop struct, not including recurse info */
 242 extern void nexthop_copy_no_recurse(struct nexthop *copy,
 243                                     const struct nexthop *nexthop,
 244                                     struct nexthop *rparent);
 245 /* Duplicates a nexthop and returns the newly allocated nexthop */
 246 extern struct nexthop *nexthop_dup(const struct nexthop *nexthop,
 247                                    struct nexthop *rparent);
 248 /* Duplicates a nexthop and returns the newly allocated nexthop */
 249 extern struct nexthop *nexthop_dup_no_recurse(const struct nexthop *nexthop,
 250                                               struct nexthop *rparent);
 251
 252 /*
 253  * Parse one or more backup index values, as comma-separated numbers,
 254  * into caller's array of uint8_ts. The array must be NEXTHOP_MAX_BACKUPS
 255  * in size. Mails back the number of values converted, and returns 0 on
 256  * success, <0 if an error in parsing.
 257  */
 258 int nexthop_str2backups(const char *str, int *num_backups,
 259                         uint8_t *backups);
 260
 261 #ifdef _FRR_ATTRIBUTE_PRINTFRR
 262 #pragma FRR printfrr_ext "%pNH"  (struct nexthop *)
 263 #endif
 264
 265 ssize_t printfrr_nhs(struct fbuf *buf, const struct nexthop *nh);
 266 #ifdef __cplusplus
 267 }
 268 #endif
 269
 270 #endif /*_LIB_NEXTHOP_H */