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