zebra/rtadv.h

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* Router advertisement
   3  * Copyright (C) 2005 6WIND <jean-mickael.guerin@6wind.com>
   4  * Copyright (C) 1999 Kunihiro Ishiguro
   5  */
   6
   7 #ifndef _ZEBRA_RTADV_H
   8 #define _ZEBRA_RTADV_H
   9
  10 #include "zebra.h"
  11 #include "vty.h"
  12 #include "typesafe.h"
  13
  14 #include "zebra/zserv.h"
  15
  16 #ifdef __cplusplus
  17 extern "C" {
  18 #endif
  19
  20 struct interface;
  21 struct zebra_if;
  22
  23 #if defined(HAVE_RTADV)
  24
  25 PREDECL_SORTLIST_UNIQ(adv_if_list);
  26 /* Structure which hold status of router advertisement. */
  27 struct rtadv {
  28         int sock;
  29
  30         struct adv_if_list_head adv_if;
  31         struct adv_if_list_head adv_msec_if;
  32
  33         struct event *ra_read;
  34         struct event *ra_timer;
  35 };
  36
  37 PREDECL_RBTREE_UNIQ(rtadv_prefixes);
  38
  39 /* Router advertisement parameter.  From RFC4861, RFC6275 and RFC4191. */
  40 struct rtadvconf {
  41         /* A flag indicating whether or not the router sends periodic Router
  42            Advertisements and responds to Router Solicitations.
  43            Default: false */
  44         int AdvSendAdvertisements;
  45
  46         /* The maximum time allowed between sending unsolicited multicast
  47            Router Advertisements from the interface, in milliseconds.
  48            MUST be no less than 70 ms [RFC6275 7.5] and no greater
  49            than 1800000 ms [RFC4861 6.2.1].
  50
  51            Default: 600000 milliseconds */
  52         int MaxRtrAdvInterval;
  53 #define RTADV_MAX_RTR_ADV_INTERVAL 600000
  54
  55         /* The minimum time allowed between sending unsolicited multicast
  56            Router Advertisements from the interface, in milliseconds.
  57            MUST be no less than 30 ms [RFC6275 7.5].
  58            MUST be no greater than .75 * MaxRtrAdvInterval.
  59
  60            Default: 0.33 * MaxRtrAdvInterval */
  61         int MinRtrAdvInterval; /* This field is currently unused. */
  62 #define RTADV_MIN_RTR_ADV_INTERVAL (0.33 * RTADV_MAX_RTR_ADV_INTERVAL)
  63
  64         /* Unsolicited Router Advertisements' interval timer. */
  65         int AdvIntervalTimer;
  66
  67         /* The true/false value to be placed in the "Managed address
  68            configuration" flag field in the Router Advertisement.  See
  69            [ADDRCONF].
  70
  71            Default: false */
  72         int AdvManagedFlag;
  73         struct timeval lastadvmanagedflag;
  74
  75
  76         /* The true/false value to be placed in the "Other stateful
  77            configuration" flag field in the Router Advertisement.  See
  78            [ADDRCONF].
  79
  80            Default: false */
  81         int AdvOtherConfigFlag;
  82         struct timeval lastadvotherconfigflag;
  83
  84         /* The value to be placed in MTU options sent by the router.  A
  85            value of zero indicates that no MTU options are sent.
  86
  87            Default: 0 */
  88         int AdvLinkMTU;
  89
  90
  91         /* The value to be placed in the Reachable Time field in the Router
  92            Advertisement messages sent by the router.  The value zero means
  93            unspecified (by this router).  MUST be no greater than 3,600,000
  94            milliseconds (1 hour).
  95
  96            Default: 0 */
  97         uint32_t AdvReachableTime;
  98 #define RTADV_MAX_REACHABLE_TIME 3600000
  99         struct timeval lastadvreachabletime;
 100
 101         /* The value to be placed in the Retrans Timer field in the Router
 102            Advertisement messages sent by the router.  The value zero means
 103            unspecified (by this router).
 104
 105            Default: 0 */
 106         int AdvRetransTimer;
 107         struct timeval lastadvretranstimer;
 108
 109         /* The default value to be placed in the Cur Hop Limit field in the
 110            Router Advertisement messages sent by the router.  The value
 111            should be set to that current diameter of the Internet.  The
 112            value zero means unspecified (by this router).
 113
 114            Default: The value specified in the "Assigned Numbers" RFC
 115            [ASSIGNED] that was in effect at the time of implementation. */
 116         int AdvCurHopLimit;
 117         struct timeval lastadvcurhoplimit;
 118
 119 #define RTADV_DEFAULT_HOPLIMIT 64 /* 64 hops */
 120
 121         /* The value to be placed in the Router Lifetime field of Router
 122            Advertisements sent from the interface, in seconds.  MUST be
 123            either zero or between MaxRtrAdvInterval and 9000 seconds.  A
 124            value of zero indicates that the router is not to be used as a
 125            default router.
 126
 127            Default: 3 * MaxRtrAdvInterval */
 128         int AdvDefaultLifetime;
 129 #define RTADV_MAX_RTRLIFETIME 9000 /* 2.5 hours */
 130
 131         /* A list of prefixes to be placed in Prefix Information options in
 132            Router Advertisement messages sent from the interface.
 133
 134            Default: all prefixes that the router advertises via routing
 135            protocols as being on-link for the interface from which the
 136            advertisement is sent. The link-local prefix SHOULD NOT be
 137            included in the list of advertised prefixes. */
 138         struct rtadv_prefixes_head prefixes[1];
 139
 140         /* The true/false value to be placed in the "Home agent"
 141            flag field in the Router Advertisement.  See [RFC6275 7.1].
 142
 143            Default: false */
 144         int AdvHomeAgentFlag;
 145 #ifndef ND_RA_FLAG_HOME_AGENT
 146 #define ND_RA_FLAG_HOME_AGENT 0x20
 147 #endif
 148
 149         /* The value to be placed in Home Agent Information option if Home
 150            Flag is set.
 151            Default: 0 */
 152         int HomeAgentPreference;
 153
 154         /* The value to be placed in Home Agent Information option if Home
 155            Flag is set. Lifetime (seconds) MUST not be greater than 18.2
 156            hours.
 157            The value 0 has special meaning: use of AdvDefaultLifetime value.
 158
 159            Default: 0 */
 160         int HomeAgentLifetime;
 161 #define RTADV_MAX_HALIFETIME 65520 /* 18.2 hours */
 162
 163         /* The true/false value to insert or not an Advertisement Interval
 164            option. See [RFC 6275 7.3]
 165
 166            Default: false */
 167         int AdvIntervalOption;
 168
 169         /* The value to be placed in the Default Router Preference field of
 170            a router advertisement. See [RFC 4191 2.1 & 2.2]
 171
 172            Default: 0 (medium) */
 173         int DefaultPreference;
 174 #define RTADV_PREF_MEDIUM 0x0 /* Per RFC4191. */
 175
 176         /*
 177          * List of recursive DNS servers to include in the RDNSS option.
 178          * See [RFC8106 5.1]
 179          *
 180          * Default: empty list; do not emit RDNSS option
 181          */
 182         struct list *AdvRDNSSList;
 183
 184         /*
 185          * List of DNS search domains to include in the DNSSL option.
 186          * See [RFC8106 5.2]
 187          *
 188          * Default: empty list; do not emit DNSSL option
 189          */
 190         struct list *AdvDNSSLList;
 191
 192         /*
 193          * rfc4861 states RAs must be sent at least 3 seconds apart.
 194          * We allow faster retransmits to speed up convergence but can
 195          * turn that capability off to meet the rfc if needed.
 196          */
 197         bool UseFastRexmit; /* True if fast rexmits are enabled */
 198
 199         uint8_t inFastRexmit; /* True if we're rexmits faster than usual */
 200
 201         /* Track if RA was configured by BGP or by the Operator or both */
 202         uint8_t ra_configured;     /* Was RA configured? */
 203 #define BGP_RA_CONFIGURED (1 << 0) /* BGP configured RA? */
 204 #define VTY_RA_CONFIGURED (1 << 1) /* Operator configured RA? */
 205 #define VTY_RA_INTERVAL_CONFIGURED                                             \
 206         (1 << 2)                  /* Operator configured RA interval */
 207         int NumFastReXmitsRemain; /* Loaded first with number of fast
 208                                      rexmits to do */
 209
 210 #define RTADV_FAST_REXMIT_PERIOD 1 /* 1 sec */
 211 #define RTADV_NUM_FAST_REXMITS 4   /* Fast Rexmit RA 4 times on certain events \
 212                                     */
 213 };
 214
 215 struct rtadv_rdnss {
 216         /* Address of recursive DNS server to advertise */
 217         struct in6_addr addr;
 218
 219         /*
 220          * Lifetime in seconds; all-ones means infinity, zero
 221          * stop using it.
 222          */
 223         uint32_t lifetime;
 224
 225         /* If lifetime not set, use a default of 3*MaxRtrAdvInterval */
 226         int lifetime_set;
 227 };
 228
 229 /*
 230  * [RFC1035 2.3.4] sets the maximum length of a domain name (a sequence of
 231  * labels, each prefixed by a length octet) at 255 octets.
 232  */
 233 #define RTADV_MAX_ENCODED_DOMAIN_NAME 255
 234
 235 struct rtadv_dnssl {
 236         /* Domain name without trailing root zone dot (NUL-terminated) */
 237         char name[RTADV_MAX_ENCODED_DOMAIN_NAME - 1];
 238
 239         /* Name encoded as in [RFC1035 3.1] */
 240         uint8_t encoded_name[RTADV_MAX_ENCODED_DOMAIN_NAME];
 241
 242         /* Actual length of encoded_name */
 243         size_t encoded_len;
 244
 245         /* Lifetime as for RDNSS */
 246         uint32_t lifetime;
 247         int lifetime_set;
 248 };
 249
 250 /* Router advertisement prefix. */
 251 struct rtadv_prefix {
 252         struct rtadv_prefixes_item item;
 253
 254         /* Prefix to be advertised. */
 255         struct prefix_ipv6 prefix;
 256
 257         /* The prefix was manually/automatically defined. */
 258         int AdvPrefixCreate;
 259
 260         /* The value to be placed in the Valid Lifetime in the Prefix */
 261         uint32_t AdvValidLifetime;
 262 #define RTADV_VALID_LIFETIME 2592000
 263
 264         /* The value to be placed in the on-link flag */
 265         int AdvOnLinkFlag;
 266
 267         /* The value to be placed in the Preferred Lifetime in the Prefix
 268            Information option, in seconds.*/
 269         uint32_t AdvPreferredLifetime;
 270 #define RTADV_PREFERRED_LIFETIME 604800
 271
 272         /* The value to be placed in the Autonomous Flag. */
 273         int AdvAutonomousFlag;
 274
 275         /* The value to be placed in the Router Address Flag [RFC6275 7.2]. */
 276         int AdvRouterAddressFlag;
 277 #ifndef ND_OPT_PI_FLAG_RADDR
 278 #define ND_OPT_PI_FLAG_RADDR         0x20
 279 #endif
 280 };
 281
 282 /* RFC4861 minimum delay between RAs  */
 283 #ifndef MIN_DELAY_BETWEEN_RAS
 284 #define MIN_DELAY_BETWEEN_RAS        3000
 285 #endif
 286
 287 /* RFC4584 Extension to Sockets API for Mobile IPv6 */
 288
 289 #ifndef ND_OPT_ADV_INTERVAL
 290 #define ND_OPT_ADV_INTERVAL     7   /* Adv Interval Option */
 291 #endif
 292 #ifndef ND_OPT_HA_INFORMATION
 293 #define ND_OPT_HA_INFORMATION   8   /* HA Information Option */
 294 #endif
 295
 296
 297 #ifndef HAVE_STRUCT_ND_OPT_ADV_INTERVAL
 298 struct nd_opt_adv_interval { /* Advertisement interval option */
 299         uint8_t nd_opt_ai_type;
 300         uint8_t nd_opt_ai_len;
 301         uint16_t nd_opt_ai_reserved;
 302         uint32_t nd_opt_ai_interval;
 303 } __attribute__((__packed__));
 304 #else
 305 #ifndef HAVE_STRUCT_ND_OPT_ADV_INTERVAL_ND_OPT_AI_TYPE
 306 /* fields may have to be renamed */
 307 #define nd_opt_ai_type          nd_opt_adv_interval_type
 308 #define nd_opt_ai_len           nd_opt_adv_interval_len
 309 #define nd_opt_ai_reserved      nd_opt_adv_interval_reserved
 310 #define nd_opt_ai_interval      nd_opt_adv_interval_ival
 311 #endif
 312 #endif
 313 #ifndef ND_OPT_RTR_ADV_INTERVAL
 314 #define ND_OPT_RTR_ADV_INTERVAL 7
 315 #endif
 316 #ifndef ND_OPT_HOME_AGENT_INFO
 317 #define ND_OPT_HOME_AGENT_INFO 8
 318 #endif
 319
 320 #ifndef HAVE_STRUCT_ND_OPT_HOMEAGENT_INFO
 321 struct nd_opt_homeagent_info { /* Home Agent info */
 322         uint8_t nd_opt_hai_type;
 323         uint8_t nd_opt_hai_len;
 324         uint16_t nd_opt_hai_reserved;
 325         uint16_t nd_opt_hai_preference;
 326         uint16_t nd_opt_hai_lifetime;
 327 } __attribute__((__packed__));
 328 #endif
 329
 330 #ifndef ND_OPT_RDNSS
 331 #define ND_OPT_RDNSS 25
 332 #endif
 333 #ifndef ND_OPT_DNSSL
 334 #define ND_OPT_DNSSL 31
 335 #endif
 336
 337 #ifndef HAVE_STRUCT_ND_OPT_RDNSS
 338 struct nd_opt_rdnss { /* Recursive DNS server option [RFC8106 5.1] */
 339         uint8_t nd_opt_rdnss_type;
 340         uint8_t nd_opt_rdnss_len;
 341         uint16_t nd_opt_rdnss_reserved;
 342         uint32_t nd_opt_rdnss_lifetime;
 343         /* Followed by one or more IPv6 addresses */
 344 } __attribute__((__packed__));
 345 #endif
 346
 347 #ifndef HAVE_STRUCT_ND_OPT_DNSSL
 348 struct nd_opt_dnssl { /* DNS search list option [RFC8106 5.2] */
 349         uint8_t nd_opt_dnssl_type;
 350         uint8_t nd_opt_dnssl_len;
 351         uint16_t nd_opt_dnssl_reserved;
 352         uint32_t nd_opt_dnssl_lifetime;
 353         /*
 354          * Followed by one or more domain names encoded as in [RFC1035 3.1].
 355          * Multiple domain names are concatenated after encoding. In any case,
 356          * the result is zero-padded to a multiple of 8 octets.
 357          */
 358 } __attribute__((__packed__));
 359 #endif
 360
 361 /*
 362  * ipv6 nd prefixes can be manually defined, derived from the kernel interface
 363  * configs or both.  If both, manual flag/timer settings are used.
 364  */
 365 enum ipv6_nd_prefix_source {
 366         PREFIX_SRC_NONE = 0,
 367         PREFIX_SRC_MANUAL,
 368         PREFIX_SRC_AUTO,
 369         PREFIX_SRC_BOTH,
 370 };
 371
 372 enum ipv6_nd_suppress_ra_status {
 373         RA_ENABLE = 0,
 374         RA_SUPPRESS,
 375 };
 376
 377 extern void rtadv_vrf_init(struct zebra_vrf *zvrf);
 378 extern void rtadv_vrf_terminate(struct zebra_vrf *zvrf);
 379 extern void rtadv_stop_ra(struct interface *ifp);
 380 extern void rtadv_stop_ra_all(void);
 381 extern void rtadv_cmd_init(void);
 382 extern void rtadv_if_init(struct zebra_if *zif);
 383 extern void rtadv_if_up(struct zebra_if *zif);
 384 extern void rtadv_if_fini(struct zebra_if *zif);
 385 extern void rtadv_add_prefix(struct zebra_if *zif, const struct prefix_ipv6 *p);
 386 extern void rtadv_delete_prefix(struct zebra_if *zif, const struct prefix *p);
 387
 388 #else /* !HAVE_RTADV */
 389 struct rtadv {
 390         /* empty structs aren't valid ISO C */
 391         char dummy;
 392 };
 393
 394 struct rtadvconf {
 395         /* same again, empty structs aren't valid ISO C */
 396         char dummy;
 397 };
 398
 399 static inline void rtadv_vrf_init(struct zebra_vrf *zvrf)
 400 {
 401 }
 402 static inline void rtadv_vrf_terminate(struct zebra_vrf *zvrf)
 403 {
 404 }
 405 static inline void rtadv_cmd_init(void)
 406 {
 407 }
 408 static inline void rtadv_if_init(struct zebra_if *zif)
 409 {
 410 }
 411 static inline void rtadv_if_up(struct zebra_if *zif)
 412 {
 413 }
 414 static inline void rtadv_if_fini(struct zebra_if *zif)
 415 {
 416 }
 417 static inline void rtadv_add_prefix(struct zebra_if *zif,
 418                                     const struct prefix_ipv6 *p)
 419 {
 420 }
 421 static inline void rtadv_delete_prefix(struct zebra_if *zif,
 422                                        const struct prefix *p)
 423 {
 424 }
 425 static inline void rtadv_stop_ra(struct interface *ifp)
 426 {
 427 }
 428 static inline void rtadv_stop_ra_all(void)
 429 {
 430 }
 431 #endif
 432
 433 extern void zebra_interface_radv_disable(ZAPI_HANDLER_ARGS);
 434 extern void zebra_interface_radv_enable(ZAPI_HANDLER_ARGS);
 435
 436 extern uint32_t rtadv_get_interfaces_configured_from_bgp(void);
 437 extern bool rtadv_compiled_in(void);
 438
 439 #ifdef __cplusplus
 440 }
 441 #endif
 442
 443 #endif /* _ZEBRA_RTADV_H */