zebra/rtadv.h

   1 /* Router advertisement
   2  * Copyright (C) 2005 6WIND <jean-mickael.guerin@6wind.com>
   3  * Copyright (C) 1999 Kunihiro Ishiguro
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef _ZEBRA_RTADV_H
  23 #define _ZEBRA_RTADV_H
  24
  25 #include "zebra.h"
  26 #include "vty.h"
  27 #include "typesafe.h"
  28
  29 #include "zebra/zserv.h"
  30
  31 #ifdef __cplusplus
  32 extern "C" {
  33 #endif
  34
  35 struct interface;
  36 struct zebra_if;
  37
  38 #if defined(HAVE_RTADV)
  39
  40 PREDECL_SORTLIST_UNIQ(adv_if_list);
  41 /* Structure which hold status of router advertisement. */
  42 struct rtadv {
  43         int sock;
  44
  45         struct adv_if_list_head adv_if;
  46         struct adv_if_list_head adv_msec_if;
  47
  48         struct thread *ra_read;
  49         struct thread *ra_timer;
  50 };
  51
  52 PREDECL_RBTREE_UNIQ(rtadv_prefixes);
  53
  54 /* Router advertisement parameter.  From RFC4861, RFC6275 and RFC4191. */
  55 struct rtadvconf {
  56         /* A flag indicating whether or not the router sends periodic Router
  57            Advertisements and responds to Router Solicitations.
  58            Default: false */
  59         int AdvSendAdvertisements;
  60
  61         /* The maximum time allowed between sending unsolicited multicast
  62            Router Advertisements from the interface, in milliseconds.
  63            MUST be no less than 70 ms [RFC6275 7.5] and no greater
  64            than 1800000 ms [RFC4861 6.2.1].
  65
  66            Default: 600000 milliseconds */
  67         int MaxRtrAdvInterval;
  68 #define RTADV_MAX_RTR_ADV_INTERVAL 600000
  69
  70         /* The minimum time allowed between sending unsolicited multicast
  71            Router Advertisements from the interface, in milliseconds.
  72            MUST be no less than 30 ms [RFC6275 7.5].
  73            MUST be no greater than .75 * MaxRtrAdvInterval.
  74
  75            Default: 0.33 * MaxRtrAdvInterval */
  76         int MinRtrAdvInterval; /* This field is currently unused. */
  77 #define RTADV_MIN_RTR_ADV_INTERVAL (0.33 * RTADV_MAX_RTR_ADV_INTERVAL)
  78
  79         /* Unsolicited Router Advertisements' interval timer. */
  80         int AdvIntervalTimer;
  81
  82         /* The true/false value to be placed in the "Managed address
  83            configuration" flag field in the Router Advertisement.  See
  84            [ADDRCONF].
  85
  86            Default: false */
  87         int AdvManagedFlag;
  88         struct timeval lastadvmanagedflag;
  89
  90
  91         /* The true/false value to be placed in the "Other stateful
  92            configuration" flag field in the Router Advertisement.  See
  93            [ADDRCONF].
  94
  95            Default: false */
  96         int AdvOtherConfigFlag;
  97         struct timeval lastadvotherconfigflag;
  98
  99         /* The value to be placed in MTU options sent by the router.  A
 100            value of zero indicates that no MTU options are sent.
 101
 102            Default: 0 */
 103         int AdvLinkMTU;
 104
 105
 106         /* The value to be placed in the Reachable Time field in the Router
 107            Advertisement messages sent by the router.  The value zero means
 108            unspecified (by this router).  MUST be no greater than 3,600,000
 109            milliseconds (1 hour).
 110
 111            Default: 0 */
 112         uint32_t AdvReachableTime;
 113 #define RTADV_MAX_REACHABLE_TIME 3600000
 114         struct timeval lastadvreachabletime;
 115
 116         /* The value to be placed in the Retrans Timer field in the Router
 117            Advertisement messages sent by the router.  The value zero means
 118            unspecified (by this router).
 119
 120            Default: 0 */
 121         int AdvRetransTimer;
 122         struct timeval lastadvretranstimer;
 123
 124         /* The default value to be placed in the Cur Hop Limit field in the
 125            Router Advertisement messages sent by the router.  The value
 126            should be set to that current diameter of the Internet.  The
 127            value zero means unspecified (by this router).
 128
 129            Default: The value specified in the "Assigned Numbers" RFC
 130            [ASSIGNED] that was in effect at the time of implementation. */
 131         int AdvCurHopLimit;
 132         struct timeval lastadvcurhoplimit;
 133
 134 #define RTADV_DEFAULT_HOPLIMIT 64 /* 64 hops */
 135
 136         /* The value to be placed in the Router Lifetime field of Router
 137            Advertisements sent from the interface, in seconds.  MUST be
 138            either zero or between MaxRtrAdvInterval and 9000 seconds.  A
 139            value of zero indicates that the router is not to be used as a
 140            default router.
 141
 142            Default: 3 * MaxRtrAdvInterval */
 143         int AdvDefaultLifetime;
 144 #define RTADV_MAX_RTRLIFETIME 9000 /* 2.5 hours */
 145
 146         /* A list of prefixes to be placed in Prefix Information options in
 147            Router Advertisement messages sent from the interface.
 148
 149            Default: all prefixes that the router advertises via routing
 150            protocols as being on-link for the interface from which the
 151            advertisement is sent. The link-local prefix SHOULD NOT be
 152            included in the list of advertised prefixes. */
 153         struct rtadv_prefixes_head prefixes[1];
 154
 155         /* The true/false value to be placed in the "Home agent"
 156            flag field in the Router Advertisement.  See [RFC6275 7.1].
 157
 158            Default: false */
 159         int AdvHomeAgentFlag;
 160 #ifndef ND_RA_FLAG_HOME_AGENT
 161 #define ND_RA_FLAG_HOME_AGENT 0x20
 162 #endif
 163
 164         /* The value to be placed in Home Agent Information option if Home
 165            Flag is set.
 166            Default: 0 */
 167         int HomeAgentPreference;
 168
 169         /* The value to be placed in Home Agent Information option if Home
 170            Flag is set. Lifetime (seconds) MUST not be greater than 18.2
 171            hours.
 172            The value 0 has special meaning: use of AdvDefaultLifetime value.
 173
 174            Default: 0 */
 175         int HomeAgentLifetime;
 176 #define RTADV_MAX_HALIFETIME 65520 /* 18.2 hours */
 177
 178         /* The true/false value to insert or not an Advertisement Interval
 179            option. See [RFC 6275 7.3]
 180
 181            Default: false */
 182         int AdvIntervalOption;
 183
 184         /* The value to be placed in the Default Router Preference field of
 185            a router advertisement. See [RFC 4191 2.1 & 2.2]
 186
 187            Default: 0 (medium) */
 188         int DefaultPreference;
 189 #define RTADV_PREF_MEDIUM 0x0 /* Per RFC4191. */
 190
 191         /*
 192          * List of recursive DNS servers to include in the RDNSS option.
 193          * See [RFC8106 5.1]
 194          *
 195          * Default: empty list; do not emit RDNSS option
 196          */
 197         struct list *AdvRDNSSList;
 198
 199         /*
 200          * List of DNS search domains to include in the DNSSL option.
 201          * See [RFC8106 5.2]
 202          *
 203          * Default: empty list; do not emit DNSSL option
 204          */
 205         struct list *AdvDNSSLList;
 206
 207         /*
 208          * rfc4861 states RAs must be sent at least 3 seconds apart.
 209          * We allow faster retransmits to speed up convergence but can
 210          * turn that capability off to meet the rfc if needed.
 211          */
 212         bool UseFastRexmit; /* True if fast rexmits are enabled */
 213
 214         uint8_t inFastRexmit; /* True if we're rexmits faster than usual */
 215
 216         /* Track if RA was configured by BGP or by the Operator or both */
 217         uint8_t ra_configured;     /* Was RA configured? */
 218 #define BGP_RA_CONFIGURED (1 << 0) /* BGP configured RA? */
 219 #define VTY_RA_CONFIGURED (1 << 1) /* Operator configured RA? */
 220 #define VTY_RA_INTERVAL_CONFIGURED                                             \
 221         (1 << 2)                  /* Operator configured RA interval */
 222         int NumFastReXmitsRemain; /* Loaded first with number of fast
 223                                      rexmits to do */
 224
 225 #define RTADV_FAST_REXMIT_PERIOD 1 /* 1 sec */
 226 #define RTADV_NUM_FAST_REXMITS 4   /* Fast Rexmit RA 4 times on certain events \
 227                                     */
 228 };
 229
 230 struct rtadv_rdnss {
 231         /* Address of recursive DNS server to advertise */
 232         struct in6_addr addr;
 233
 234         /*
 235          * Lifetime in seconds; all-ones means infinity, zero
 236          * stop using it.
 237          */
 238         uint32_t lifetime;
 239
 240         /* If lifetime not set, use a default of 3*MaxRtrAdvInterval */
 241         int lifetime_set;
 242 };
 243
 244 /*
 245  * [RFC1035 2.3.4] sets the maximum length of a domain name (a sequence of
 246  * labels, each prefixed by a length octet) at 255 octets.
 247  */
 248 #define RTADV_MAX_ENCODED_DOMAIN_NAME 255
 249
 250 struct rtadv_dnssl {
 251         /* Domain name without trailing root zone dot (NUL-terminated) */
 252         char name[RTADV_MAX_ENCODED_DOMAIN_NAME - 1];
 253
 254         /* Name encoded as in [RFC1035 3.1] */
 255         uint8_t encoded_name[RTADV_MAX_ENCODED_DOMAIN_NAME];
 256
 257         /* Actual length of encoded_name */
 258         size_t encoded_len;
 259
 260         /* Lifetime as for RDNSS */
 261         uint32_t lifetime;
 262         int lifetime_set;
 263 };
 264
 265 /* Router advertisement prefix. */
 266 struct rtadv_prefix {
 267         struct rtadv_prefixes_item item;
 268
 269         /* Prefix to be advertised. */
 270         struct prefix_ipv6 prefix;
 271
 272         /* The prefix was manually/automatically defined. */
 273         int AdvPrefixCreate;
 274
 275         /* The value to be placed in the Valid Lifetime in the Prefix */
 276         uint32_t AdvValidLifetime;
 277 #define RTADV_VALID_LIFETIME 2592000
 278
 279         /* The value to be placed in the on-link flag */
 280         int AdvOnLinkFlag;
 281
 282         /* The value to be placed in the Preferred Lifetime in the Prefix
 283            Information option, in seconds.*/
 284         uint32_t AdvPreferredLifetime;
 285 #define RTADV_PREFERRED_LIFETIME 604800
 286
 287         /* The value to be placed in the Autonomous Flag. */
 288         int AdvAutonomousFlag;
 289
 290         /* The value to be placed in the Router Address Flag [RFC6275 7.2]. */
 291         int AdvRouterAddressFlag;
 292 #ifndef ND_OPT_PI_FLAG_RADDR
 293 #define ND_OPT_PI_FLAG_RADDR         0x20
 294 #endif
 295 };
 296
 297 /* RFC4861 minimum delay between RAs  */
 298 #ifndef MIN_DELAY_BETWEEN_RAS
 299 #define MIN_DELAY_BETWEEN_RAS        3000
 300 #endif
 301
 302 /* RFC4584 Extension to Sockets API for Mobile IPv6 */
 303
 304 #ifndef ND_OPT_ADV_INTERVAL
 305 #define ND_OPT_ADV_INTERVAL     7   /* Adv Interval Option */
 306 #endif
 307 #ifndef ND_OPT_HA_INFORMATION
 308 #define ND_OPT_HA_INFORMATION   8   /* HA Information Option */
 309 #endif
 310
 311 #ifndef HAVE_STRUCT_ND_OPT_ADV_INTERVAL
 312 struct nd_opt_adv_interval { /* Advertisement interval option */
 313         uint8_t nd_opt_ai_type;
 314         uint8_t nd_opt_ai_len;
 315         uint16_t nd_opt_ai_reserved;
 316         uint32_t nd_opt_ai_interval;
 317 } __attribute__((__packed__));
 318 #else
 319 #ifndef HAVE_STRUCT_ND_OPT_ADV_INTERVAL_ND_OPT_AI_TYPE
 320 /* fields may have to be renamed */
 321 #define nd_opt_ai_type          nd_opt_adv_interval_type
 322 #define nd_opt_ai_len           nd_opt_adv_interval_len
 323 #define nd_opt_ai_reserved      nd_opt_adv_interval_reserved
 324 #define nd_opt_ai_interval      nd_opt_adv_interval_ival
 325 #endif
 326 #endif
 327
 328 #ifndef HAVE_STRUCT_ND_OPT_HOMEAGENT_INFO
 329 struct nd_opt_homeagent_info { /* Home Agent info */
 330         uint8_t nd_opt_hai_type;
 331         uint8_t nd_opt_hai_len;
 332         uint16_t nd_opt_hai_reserved;
 333         uint16_t nd_opt_hai_preference;
 334         uint16_t nd_opt_hai_lifetime;
 335 } __attribute__((__packed__));
 336 #endif
 337
 338 #ifndef ND_OPT_RDNSS
 339 #define ND_OPT_RDNSS 25
 340 #endif
 341 #ifndef ND_OPT_DNSSL
 342 #define ND_OPT_DNSSL 31
 343 #endif
 344
 345 #ifndef HAVE_STRUCT_ND_OPT_RDNSS
 346 struct nd_opt_rdnss { /* Recursive DNS server option [RFC8106 5.1] */
 347         uint8_t nd_opt_rdnss_type;
 348         uint8_t nd_opt_rdnss_len;
 349         uint16_t nd_opt_rdnss_reserved;
 350         uint32_t nd_opt_rdnss_lifetime;
 351         /* Followed by one or more IPv6 addresses */
 352 } __attribute__((__packed__));
 353 #endif
 354
 355 #ifndef HAVE_STRUCT_ND_OPT_DNSSL
 356 struct nd_opt_dnssl { /* DNS search list option [RFC8106 5.2] */
 357         uint8_t nd_opt_dnssl_type;
 358         uint8_t nd_opt_dnssl_len;
 359         uint16_t nd_opt_dnssl_reserved;
 360         uint32_t nd_opt_dnssl_lifetime;
 361         /*
 362          * Followed by one or more domain names encoded as in [RFC1035 3.1].
 363          * Multiple domain names are concatenated after encoding. In any case,
 364          * the result is zero-padded to a multiple of 8 octets.
 365          */
 366 } __attribute__((__packed__));
 367 #endif
 368
 369 /*
 370  * ipv6 nd prefixes can be manually defined, derived from the kernel interface
 371  * configs or both.  If both, manual flag/timer settings are used.
 372  */
 373 enum ipv6_nd_prefix_source {
 374         PREFIX_SRC_NONE = 0,
 375         PREFIX_SRC_MANUAL,
 376         PREFIX_SRC_AUTO,
 377         PREFIX_SRC_BOTH,
 378 };
 379
 380 enum ipv6_nd_suppress_ra_status {
 381         RA_ENABLE = 0,
 382         RA_SUPPRESS,
 383 };
 384
 385 extern void rtadv_vrf_init(struct zebra_vrf *zvrf);
 386 extern void rtadv_vrf_terminate(struct zebra_vrf *zvrf);
 387 extern void rtadv_stop_ra(struct interface *ifp);
 388 extern void rtadv_stop_ra_all(void);
 389 extern void rtadv_cmd_init(void);
 390 extern void rtadv_if_init(struct zebra_if *zif);
 391 extern void rtadv_if_up(struct zebra_if *zif);
 392 extern void rtadv_if_fini(struct zebra_if *zif);
 393 extern void rtadv_add_prefix(struct zebra_if *zif, const struct prefix_ipv6 *p);
 394 extern void rtadv_delete_prefix(struct zebra_if *zif, const struct prefix *p);
 395
 396 #else /* !HAVE_RTADV */
 397 struct rtadv {
 398         /* empty structs aren't valid ISO C */
 399         char dummy;
 400 };
 401
 402 struct rtadvconf {
 403         /* same again, empty structs aren't valid ISO C */
 404         char dummy;
 405 };
 406
 407 static inline void rtadv_vrf_init(struct zebra_vrf *zvrf)
 408 {
 409 }
 410 static inline void rtadv_vrf_terminate(struct zebra_vrf *zvrf)
 411 {
 412 }
 413 static inline void rtadv_cmd_init(void)
 414 {
 415 }
 416 static inline void rtadv_if_init(struct zebra_if *zif)
 417 {
 418 }
 419 static inline void rtadv_if_up(struct zebra_if *zif)
 420 {
 421 }
 422 static inline void rtadv_if_fini(struct zebra_if *zif)
 423 {
 424 }
 425 static inline void rtadv_add_prefix(struct zebra_if *zif,
 426                                     const struct prefix_ipv6 *p)
 427 {
 428 }
 429 static inline void rtadv_delete_prefix(struct zebra_if *zif,
 430                                        const struct prefix *p)
 431 {
 432 }
 433 static inline void rtadv_stop_ra(struct interface *ifp)
 434 {
 435 }
 436 static inline void rtadv_stop_ra_all(void)
 437 {
 438 }
 439 #endif
 440
 441 extern void zebra_interface_radv_disable(ZAPI_HANDLER_ARGS);
 442 extern void zebra_interface_radv_enable(ZAPI_HANDLER_ARGS);
 443
 444 extern uint32_t rtadv_get_interfaces_configured_from_bgp(void);
 445 extern bool rtadv_compiled_in(void);
 446
 447 #ifdef __cplusplus
 448 }
 449 #endif
 450
 451 #endif /* _ZEBRA_RTADV_H */