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