1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _NDISC_H 3 #define _NDISC_H 4 5 #include <net/ipv6_stubs.h> 6 7 /* 8 * ICMP codes for neighbour discovery messages 9 */ 10 11 #define NDISC_ROUTER_SOLICITATION 133 12 #define NDISC_ROUTER_ADVERTISEMENT 134 13 #define NDISC_NEIGHBOUR_SOLICITATION 135 14 #define NDISC_NEIGHBOUR_ADVERTISEMENT 136 15 #define NDISC_REDIRECT 137 16 17 /* 18 * Router type: cross-layer information from link-layer to 19 * IPv6 layer reported by certain link types (e.g., RFC4214). 20 */ 21 #define NDISC_NODETYPE_UNSPEC 0 /* unspecified (default) */ 22 #define NDISC_NODETYPE_HOST 1 /* host or unauthorized router */ 23 #define NDISC_NODETYPE_NODEFAULT 2 /* non-default router */ 24 #define NDISC_NODETYPE_DEFAULT 3 /* default router */ 25 26 /* 27 * ndisc options 28 */ 29 30 enum { 31 __ND_OPT_PREFIX_INFO_END = 0, 32 ND_OPT_SOURCE_LL_ADDR = 1, /* RFC2461 */ 33 ND_OPT_TARGET_LL_ADDR = 2, /* RFC2461 */ 34 ND_OPT_PREFIX_INFO = 3, /* RFC2461 */ 35 ND_OPT_REDIRECT_HDR = 4, /* RFC2461 */ 36 ND_OPT_MTU = 5, /* RFC2461 */ 37 ND_OPT_NONCE = 14, /* RFC7527 */ 38 __ND_OPT_ARRAY_MAX, 39 ND_OPT_ROUTE_INFO = 24, /* RFC4191 */ 40 ND_OPT_RDNSS = 25, /* RFC5006 */ 41 ND_OPT_DNSSL = 31, /* RFC6106 */ 42 ND_OPT_6CO = 34, /* RFC6775 */ 43 ND_OPT_CAPTIVE_PORTAL = 37, /* RFC7710 */ 44 ND_OPT_PREF64 = 38, /* RFC8781 */ 45 __ND_OPT_MAX 46 }; 47 48 #define MAX_RTR_SOLICITATION_DELAY HZ 49 50 #define ND_REACHABLE_TIME (30*HZ) 51 #define ND_RETRANS_TIMER HZ 52 53 #include <linux/compiler.h> 54 #include <linux/icmpv6.h> 55 #include <linux/in6.h> 56 #include <linux/types.h> 57 #include <linux/if_arp.h> 58 #include <linux/netdevice.h> 59 #include <linux/hash.h> 60 61 #include <net/neighbour.h> 62 63 struct ctl_table; 64 struct inet6_dev; 65 struct net_device; 66 struct net_proto_family; 67 struct sk_buff; 68 struct prefix_info; 69 70 extern struct neigh_table nd_tbl; 71 72 struct nd_msg { 73 struct icmp6hdr icmph; 74 struct in6_addr target; 75 __u8 opt[]; 76 }; 77 78 struct rs_msg { 79 struct icmp6hdr icmph; 80 __u8 opt[]; 81 }; 82 83 struct ra_msg { 84 struct icmp6hdr icmph; 85 __be32 reachable_time; 86 __be32 retrans_timer; 87 }; 88 89 struct rd_msg { 90 struct icmp6hdr icmph; 91 struct in6_addr target; 92 struct in6_addr dest; 93 __u8 opt[]; 94 }; 95 96 struct nd_opt_hdr { 97 __u8 nd_opt_type; 98 __u8 nd_opt_len; 99 } __packed; 100 101 /* ND options */ 102 struct ndisc_options { 103 struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX]; 104 #ifdef CONFIG_IPV6_ROUTE_INFO 105 struct nd_opt_hdr *nd_opts_ri; 106 struct nd_opt_hdr *nd_opts_ri_end; 107 #endif 108 struct nd_opt_hdr *nd_useropts; 109 struct nd_opt_hdr *nd_useropts_end; 110 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) 111 struct nd_opt_hdr *nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR + 1]; 112 #endif 113 }; 114 115 #define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR] 116 #define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR] 117 #define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO] 118 #define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END] 119 #define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR] 120 #define nd_opts_mtu nd_opt_array[ND_OPT_MTU] 121 #define nd_opts_nonce nd_opt_array[ND_OPT_NONCE] 122 #define nd_802154_opts_src_lladdr nd_802154_opt_array[ND_OPT_SOURCE_LL_ADDR] 123 #define nd_802154_opts_tgt_lladdr nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR] 124 125 #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7) 126 127 struct ndisc_options *ndisc_parse_options(const struct net_device *dev, 128 u8 *opt, int opt_len, 129 struct ndisc_options *ndopts); 130 131 void __ndisc_fill_addr_option(struct sk_buff *skb, int type, const void *data, 132 int data_len, int pad); 133 134 #define NDISC_OPS_REDIRECT_DATA_SPACE 2 135 136 /* 137 * This structure defines the hooks for IPv6 neighbour discovery. 138 * The following hooks can be defined; unless noted otherwise, they are 139 * optional and can be filled with a null pointer. 140 * 141 * int (*parse_options)(const struct net_device *dev, 142 * struct nd_opt_hdr *nd_opt, 143 * struct ndisc_options *ndopts): 144 * This function is called while parsing ndisc ops and put each position 145 * as pointer into ndopts. If this function return unequal 0, then this 146 * function took care about the ndisc option, if 0 then the IPv6 ndisc 147 * option parser will take care about that option. 148 * 149 * void (*update)(const struct net_device *dev, struct neighbour *n, 150 * u32 flags, u8 icmp6_type, 151 * const struct ndisc_options *ndopts): 152 * This function is called when IPv6 ndisc updates the neighbour cache 153 * entry. Additional options which can be updated may be previously 154 * parsed by parse_opts callback and accessible over ndopts parameter. 155 * 156 * int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type, 157 * struct neighbour *neigh, u8 *ha_buf, 158 * u8 **ha): 159 * This function is called when the necessary option space will be 160 * calculated before allocating a skb. The parameters neigh, ha_buf 161 * abd ha are available on NDISC_REDIRECT messages only. 162 * 163 * void (*fill_addr_option)(const struct net_device *dev, 164 * struct sk_buff *skb, u8 icmp6_type, 165 * const u8 *ha): 166 * This function is called when the skb will finally fill the option 167 * fields inside skb. NOTE: this callback should fill the option 168 * fields to the skb which are previously indicated by opt_space 169 * parameter. That means the decision to add such option should 170 * not lost between these two callbacks, e.g. protected by interface 171 * up state. 172 * 173 * void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev, 174 * const struct prefix_info *pinfo, 175 * struct inet6_dev *in6_dev, 176 * struct in6_addr *addr, 177 * int addr_type, u32 addr_flags, 178 * bool sllao, bool tokenized, 179 * __u32 valid_lft, u32 prefered_lft, 180 * bool dev_addr_generated): 181 * This function is called when a RA messages is received with valid 182 * PIO option fields and an IPv6 address will be added to the interface 183 * for autoconfiguration. The parameter dev_addr_generated reports about 184 * if the address was based on dev->dev_addr or not. This can be used 185 * to add a second address if link-layer operates with two link layer 186 * addresses. E.g. 802.15.4 6LoWPAN. 187 */ 188 struct ndisc_ops { 189 int (*parse_options)(const struct net_device *dev, 190 struct nd_opt_hdr *nd_opt, 191 struct ndisc_options *ndopts); 192 void (*update)(const struct net_device *dev, struct neighbour *n, 193 u32 flags, u8 icmp6_type, 194 const struct ndisc_options *ndopts); 195 int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type, 196 struct neighbour *neigh, u8 *ha_buf, 197 u8 **ha); 198 void (*fill_addr_option)(const struct net_device *dev, 199 struct sk_buff *skb, u8 icmp6_type, 200 const u8 *ha); 201 void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev, 202 const struct prefix_info *pinfo, 203 struct inet6_dev *in6_dev, 204 struct in6_addr *addr, 205 int addr_type, u32 addr_flags, 206 bool sllao, bool tokenized, 207 __u32 valid_lft, u32 prefered_lft, 208 bool dev_addr_generated); 209 }; 210 211 #if IS_ENABLED(CONFIG_IPV6) 212 static inline int ndisc_ops_parse_options(const struct net_device *dev, 213 struct nd_opt_hdr *nd_opt, 214 struct ndisc_options *ndopts) 215 { 216 if (dev->ndisc_ops && dev->ndisc_ops->parse_options) 217 return dev->ndisc_ops->parse_options(dev, nd_opt, ndopts); 218 else 219 return 0; 220 } 221 222 static inline void ndisc_ops_update(const struct net_device *dev, 223 struct neighbour *n, u32 flags, 224 u8 icmp6_type, 225 const struct ndisc_options *ndopts) 226 { 227 if (dev->ndisc_ops && dev->ndisc_ops->update) 228 dev->ndisc_ops->update(dev, n, flags, icmp6_type, ndopts); 229 } 230 231 static inline int ndisc_ops_opt_addr_space(const struct net_device *dev, 232 u8 icmp6_type) 233 { 234 if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space && 235 icmp6_type != NDISC_REDIRECT) 236 return dev->ndisc_ops->opt_addr_space(dev, icmp6_type, NULL, 237 NULL, NULL); 238 else 239 return 0; 240 } 241 242 static inline int ndisc_ops_redirect_opt_addr_space(const struct net_device *dev, 243 struct neighbour *neigh, 244 u8 *ha_buf, u8 **ha) 245 { 246 if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space) 247 return dev->ndisc_ops->opt_addr_space(dev, NDISC_REDIRECT, 248 neigh, ha_buf, ha); 249 else 250 return 0; 251 } 252 253 static inline void ndisc_ops_fill_addr_option(const struct net_device *dev, 254 struct sk_buff *skb, 255 u8 icmp6_type) 256 { 257 if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option && 258 icmp6_type != NDISC_REDIRECT) 259 dev->ndisc_ops->fill_addr_option(dev, skb, icmp6_type, NULL); 260 } 261 262 static inline void ndisc_ops_fill_redirect_addr_option(const struct net_device *dev, 263 struct sk_buff *skb, 264 const u8 *ha) 265 { 266 if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option) 267 dev->ndisc_ops->fill_addr_option(dev, skb, NDISC_REDIRECT, ha); 268 } 269 270 static inline void ndisc_ops_prefix_rcv_add_addr(struct net *net, 271 struct net_device *dev, 272 const struct prefix_info *pinfo, 273 struct inet6_dev *in6_dev, 274 struct in6_addr *addr, 275 int addr_type, u32 addr_flags, 276 bool sllao, bool tokenized, 277 __u32 valid_lft, 278 u32 prefered_lft, 279 bool dev_addr_generated) 280 { 281 if (dev->ndisc_ops && dev->ndisc_ops->prefix_rcv_add_addr) 282 dev->ndisc_ops->prefix_rcv_add_addr(net, dev, pinfo, in6_dev, 283 addr, addr_type, 284 addr_flags, sllao, 285 tokenized, valid_lft, 286 prefered_lft, 287 dev_addr_generated); 288 } 289 #endif 290 291 /* 292 * Return the padding between the option length and the start of the 293 * link addr. Currently only IP-over-InfiniBand needs this, although 294 * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may 295 * also need a pad of 2. 296 */ 297 static inline int ndisc_addr_option_pad(unsigned short type) 298 { 299 switch (type) { 300 case ARPHRD_INFINIBAND: return 2; 301 default: return 0; 302 } 303 } 304 305 static inline int __ndisc_opt_addr_space(unsigned char addr_len, int pad) 306 { 307 return NDISC_OPT_SPACE(addr_len + pad); 308 } 309 310 #if IS_ENABLED(CONFIG_IPV6) 311 static inline int ndisc_opt_addr_space(struct net_device *dev, u8 icmp6_type) 312 { 313 return __ndisc_opt_addr_space(dev->addr_len, 314 ndisc_addr_option_pad(dev->type)) + 315 ndisc_ops_opt_addr_space(dev, icmp6_type); 316 } 317 318 static inline int ndisc_redirect_opt_addr_space(struct net_device *dev, 319 struct neighbour *neigh, 320 u8 *ops_data_buf, 321 u8 **ops_data) 322 { 323 return __ndisc_opt_addr_space(dev->addr_len, 324 ndisc_addr_option_pad(dev->type)) + 325 ndisc_ops_redirect_opt_addr_space(dev, neigh, ops_data_buf, 326 ops_data); 327 } 328 #endif 329 330 static inline u8 *__ndisc_opt_addr_data(struct nd_opt_hdr *p, 331 unsigned char addr_len, int prepad) 332 { 333 u8 *lladdr = (u8 *)(p + 1); 334 int lladdrlen = p->nd_opt_len << 3; 335 if (lladdrlen != __ndisc_opt_addr_space(addr_len, prepad)) 336 return NULL; 337 return lladdr + prepad; 338 } 339 340 static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p, 341 struct net_device *dev) 342 { 343 return __ndisc_opt_addr_data(p, dev->addr_len, 344 ndisc_addr_option_pad(dev->type)); 345 } 346 347 static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd) 348 { 349 const u32 *p32 = pkey; 350 351 return (((p32[0] ^ hash32_ptr(dev)) * hash_rnd[0]) + 352 (p32[1] * hash_rnd[1]) + 353 (p32[2] * hash_rnd[2]) + 354 (p32[3] * hash_rnd[3])); 355 } 356 357 static inline struct neighbour *__ipv6_neigh_lookup_noref(struct net_device *dev, const void *pkey) 358 { 359 return ___neigh_lookup_noref(&nd_tbl, neigh_key_eq128, ndisc_hashfn, pkey, dev); 360 } 361 362 static inline 363 struct neighbour *__ipv6_neigh_lookup_noref_stub(struct net_device *dev, 364 const void *pkey) 365 { 366 return ___neigh_lookup_noref(ipv6_stub->nd_tbl, neigh_key_eq128, 367 ndisc_hashfn, pkey, dev); 368 } 369 370 static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey) 371 { 372 struct neighbour *n; 373 374 rcu_read_lock(); 375 n = __ipv6_neigh_lookup_noref(dev, pkey); 376 if (n && !refcount_inc_not_zero(&n->refcnt)) 377 n = NULL; 378 rcu_read_unlock(); 379 380 return n; 381 } 382 383 static inline void __ipv6_confirm_neigh(struct net_device *dev, 384 const void *pkey) 385 { 386 struct neighbour *n; 387 388 rcu_read_lock(); 389 n = __ipv6_neigh_lookup_noref(dev, pkey); 390 neigh_confirm(n); 391 rcu_read_unlock(); 392 } 393 394 static inline void __ipv6_confirm_neigh_stub(struct net_device *dev, 395 const void *pkey) 396 { 397 struct neighbour *n; 398 399 rcu_read_lock(); 400 n = __ipv6_neigh_lookup_noref_stub(dev, pkey); 401 neigh_confirm(n); 402 rcu_read_unlock(); 403 } 404 405 /* uses ipv6_stub and is meant for use outside of IPv6 core */ 406 static inline struct neighbour *ip_neigh_gw6(struct net_device *dev, 407 const void *addr) 408 { 409 struct neighbour *neigh; 410 411 neigh = __ipv6_neigh_lookup_noref_stub(dev, addr); 412 if (unlikely(!neigh)) 413 neigh = __neigh_create(ipv6_stub->nd_tbl, addr, dev, false); 414 415 return neigh; 416 } 417 418 int ndisc_init(void); 419 int ndisc_late_init(void); 420 421 void ndisc_late_cleanup(void); 422 void ndisc_cleanup(void); 423 424 enum skb_drop_reason ndisc_rcv(struct sk_buff *skb); 425 426 struct sk_buff *ndisc_ns_create(struct net_device *dev, const struct in6_addr *solicit, 427 const struct in6_addr *saddr, u64 nonce); 428 void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit, 429 const struct in6_addr *daddr, const struct in6_addr *saddr, 430 u64 nonce); 431 432 void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr, 433 const struct in6_addr *saddr); 434 435 void ndisc_send_rs(struct net_device *dev, 436 const struct in6_addr *saddr, const struct in6_addr *daddr); 437 void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr, 438 const struct in6_addr *solicited_addr, 439 bool router, bool solicited, bool override, bool inc_opt); 440 441 void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target); 442 443 int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, 444 int dir); 445 446 void ndisc_update(const struct net_device *dev, struct neighbour *neigh, 447 const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type, 448 struct ndisc_options *ndopts); 449 450 /* 451 * IGMP 452 */ 453 int igmp6_init(void); 454 int igmp6_late_init(void); 455 456 void igmp6_cleanup(void); 457 void igmp6_late_cleanup(void); 458 459 void igmp6_event_query(struct sk_buff *skb); 460 461 void igmp6_event_report(struct sk_buff *skb); 462 463 464 #ifdef CONFIG_SYSCTL 465 int ndisc_ifinfo_sysctl_change(const struct ctl_table *ctl, int write, 466 void *buffer, size_t *lenp, loff_t *ppos); 467 #endif 468 469 void inet6_ifinfo_notify(int event, struct inet6_dev *idev); 470 471 #endif 472