1 /* 2 * Linux INET6 implementation 3 * 4 * Authors: 5 * Pedro Roque <roque@di.fc.ul.pt> 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 */ 12 13 #ifndef _NET_IPV6_H 14 #define _NET_IPV6_H 15 16 #include <linux/ipv6.h> 17 #include <linux/hardirq.h> 18 #include <linux/jhash.h> 19 #include <linux/refcount.h> 20 #include <net/if_inet6.h> 21 #include <net/ndisc.h> 22 #include <net/flow.h> 23 #include <net/flow_dissector.h> 24 #include <net/snmp.h> 25 #include <net/netns/hash.h> 26 27 #define SIN6_LEN_RFC2133 24 28 29 #define IPV6_MAXPLEN 65535 30 31 /* 32 * NextHeader field of IPv6 header 33 */ 34 35 #define NEXTHDR_HOP 0 /* Hop-by-hop option header. */ 36 #define NEXTHDR_TCP 6 /* TCP segment. */ 37 #define NEXTHDR_UDP 17 /* UDP message. */ 38 #define NEXTHDR_IPV6 41 /* IPv6 in IPv6 */ 39 #define NEXTHDR_ROUTING 43 /* Routing header. */ 40 #define NEXTHDR_FRAGMENT 44 /* Fragmentation/reassembly header. */ 41 #define NEXTHDR_GRE 47 /* GRE header. */ 42 #define NEXTHDR_ESP 50 /* Encapsulating security payload. */ 43 #define NEXTHDR_AUTH 51 /* Authentication header. */ 44 #define NEXTHDR_ICMP 58 /* ICMP for IPv6. */ 45 #define NEXTHDR_NONE 59 /* No next header */ 46 #define NEXTHDR_DEST 60 /* Destination options header. */ 47 #define NEXTHDR_SCTP 132 /* SCTP message. */ 48 #define NEXTHDR_MOBILITY 135 /* Mobility header. */ 49 50 #define NEXTHDR_MAX 255 51 52 #define IPV6_DEFAULT_HOPLIMIT 64 53 #define IPV6_DEFAULT_MCASTHOPS 1 54 55 /* Limits on Hop-by-Hop and Destination options. 56 * 57 * Per RFC8200 there is no limit on the maximum number or lengths of options in 58 * Hop-by-Hop or Destination options other then the packet must fit in an MTU. 59 * We allow configurable limits in order to mitigate potential denial of 60 * service attacks. 61 * 62 * There are three limits that may be set: 63 * - Limit the number of options in a Hop-by-Hop or Destination options 64 * extension header 65 * - Limit the byte length of a Hop-by-Hop or Destination options extension 66 * header 67 * - Disallow unknown options 68 * 69 * The limits are expressed in corresponding sysctls: 70 * 71 * ipv6.sysctl.max_dst_opts_cnt 72 * ipv6.sysctl.max_hbh_opts_cnt 73 * ipv6.sysctl.max_dst_opts_len 74 * ipv6.sysctl.max_hbh_opts_len 75 * 76 * max_*_opts_cnt is the number of TLVs that are allowed for Destination 77 * options or Hop-by-Hop options. If the number is less than zero then unknown 78 * TLVs are disallowed and the number of known options that are allowed is the 79 * absolute value. Setting the value to INT_MAX indicates no limit. 80 * 81 * max_*_opts_len is the length limit in bytes of a Destination or 82 * Hop-by-Hop options extension header. Setting the value to INT_MAX 83 * indicates no length limit. 84 * 85 * If a limit is exceeded when processing an extension header the packet is 86 * silently discarded. 87 */ 88 89 /* Default limits for Hop-by-Hop and Destination options */ 90 #define IP6_DEFAULT_MAX_DST_OPTS_CNT 8 91 #define IP6_DEFAULT_MAX_HBH_OPTS_CNT 8 92 #define IP6_DEFAULT_MAX_DST_OPTS_LEN INT_MAX /* No limit */ 93 #define IP6_DEFAULT_MAX_HBH_OPTS_LEN INT_MAX /* No limit */ 94 95 /* 96 * Addr type 97 * 98 * type - unicast | multicast 99 * scope - local | site | global 100 * v4 - compat 101 * v4mapped 102 * any 103 * loopback 104 */ 105 106 #define IPV6_ADDR_ANY 0x0000U 107 108 #define IPV6_ADDR_UNICAST 0x0001U 109 #define IPV6_ADDR_MULTICAST 0x0002U 110 111 #define IPV6_ADDR_LOOPBACK 0x0010U 112 #define IPV6_ADDR_LINKLOCAL 0x0020U 113 #define IPV6_ADDR_SITELOCAL 0x0040U 114 115 #define IPV6_ADDR_COMPATv4 0x0080U 116 117 #define IPV6_ADDR_SCOPE_MASK 0x00f0U 118 119 #define IPV6_ADDR_MAPPED 0x1000U 120 121 /* 122 * Addr scopes 123 */ 124 #define IPV6_ADDR_MC_SCOPE(a) \ 125 ((a)->s6_addr[1] & 0x0f) /* nonstandard */ 126 #define __IPV6_ADDR_SCOPE_INVALID -1 127 #define IPV6_ADDR_SCOPE_NODELOCAL 0x01 128 #define IPV6_ADDR_SCOPE_LINKLOCAL 0x02 129 #define IPV6_ADDR_SCOPE_SITELOCAL 0x05 130 #define IPV6_ADDR_SCOPE_ORGLOCAL 0x08 131 #define IPV6_ADDR_SCOPE_GLOBAL 0x0e 132 133 /* 134 * Addr flags 135 */ 136 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a) \ 137 ((a)->s6_addr[1] & 0x10) 138 #define IPV6_ADDR_MC_FLAG_PREFIX(a) \ 139 ((a)->s6_addr[1] & 0x20) 140 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a) \ 141 ((a)->s6_addr[1] & 0x40) 142 143 /* 144 * fragmentation header 145 */ 146 147 struct frag_hdr { 148 __u8 nexthdr; 149 __u8 reserved; 150 __be16 frag_off; 151 __be32 identification; 152 }; 153 154 #define IP6_MF 0x0001 155 #define IP6_OFFSET 0xFFF8 156 157 #define IP6_REPLY_MARK(net, mark) \ 158 ((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0) 159 160 #include <net/sock.h> 161 162 /* sysctls */ 163 extern int sysctl_mld_max_msf; 164 extern int sysctl_mld_qrv; 165 166 #define _DEVINC(net, statname, mod, idev, field) \ 167 ({ \ 168 struct inet6_dev *_idev = (idev); \ 169 if (likely(_idev != NULL)) \ 170 mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\ 171 mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\ 172 }) 173 174 /* per device counters are atomic_long_t */ 175 #define _DEVINCATOMIC(net, statname, mod, idev, field) \ 176 ({ \ 177 struct inet6_dev *_idev = (idev); \ 178 if (likely(_idev != NULL)) \ 179 SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \ 180 mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\ 181 }) 182 183 /* per device and per net counters are atomic_long_t */ 184 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field) \ 185 ({ \ 186 struct inet6_dev *_idev = (idev); \ 187 if (likely(_idev != NULL)) \ 188 SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \ 189 SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\ 190 }) 191 192 #define _DEVADD(net, statname, mod, idev, field, val) \ 193 ({ \ 194 struct inet6_dev *_idev = (idev); \ 195 if (likely(_idev != NULL)) \ 196 mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \ 197 mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\ 198 }) 199 200 #define _DEVUPD(net, statname, mod, idev, field, val) \ 201 ({ \ 202 struct inet6_dev *_idev = (idev); \ 203 if (likely(_idev != NULL)) \ 204 mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \ 205 mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\ 206 }) 207 208 /* MIBs */ 209 210 #define IP6_INC_STATS(net, idev,field) \ 211 _DEVINC(net, ipv6, , idev, field) 212 #define __IP6_INC_STATS(net, idev,field) \ 213 _DEVINC(net, ipv6, __, idev, field) 214 #define IP6_ADD_STATS(net, idev,field,val) \ 215 _DEVADD(net, ipv6, , idev, field, val) 216 #define __IP6_ADD_STATS(net, idev,field,val) \ 217 _DEVADD(net, ipv6, __, idev, field, val) 218 #define IP6_UPD_PO_STATS(net, idev,field,val) \ 219 _DEVUPD(net, ipv6, , idev, field, val) 220 #define __IP6_UPD_PO_STATS(net, idev,field,val) \ 221 _DEVUPD(net, ipv6, __, idev, field, val) 222 #define ICMP6_INC_STATS(net, idev, field) \ 223 _DEVINCATOMIC(net, icmpv6, , idev, field) 224 #define __ICMP6_INC_STATS(net, idev, field) \ 225 _DEVINCATOMIC(net, icmpv6, __, idev, field) 226 227 #define ICMP6MSGOUT_INC_STATS(net, idev, field) \ 228 _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256) 229 #define ICMP6MSGIN_INC_STATS(net, idev, field) \ 230 _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field) 231 232 struct ip6_ra_chain { 233 struct ip6_ra_chain *next; 234 struct sock *sk; 235 int sel; 236 void (*destructor)(struct sock *); 237 }; 238 239 extern struct ip6_ra_chain *ip6_ra_chain; 240 extern rwlock_t ip6_ra_lock; 241 242 /* 243 This structure is prepared by protocol, when parsing 244 ancillary data and passed to IPv6. 245 */ 246 247 struct ipv6_txoptions { 248 refcount_t refcnt; 249 /* Length of this structure */ 250 int tot_len; 251 252 /* length of extension headers */ 253 254 __u16 opt_flen; /* after fragment hdr */ 255 __u16 opt_nflen; /* before fragment hdr */ 256 257 struct ipv6_opt_hdr *hopopt; 258 struct ipv6_opt_hdr *dst0opt; 259 struct ipv6_rt_hdr *srcrt; /* Routing Header */ 260 struct ipv6_opt_hdr *dst1opt; 261 struct rcu_head rcu; 262 /* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */ 263 }; 264 265 struct ip6_flowlabel { 266 struct ip6_flowlabel __rcu *next; 267 __be32 label; 268 atomic_t users; 269 struct in6_addr dst; 270 struct ipv6_txoptions *opt; 271 unsigned long linger; 272 struct rcu_head rcu; 273 u8 share; 274 union { 275 struct pid *pid; 276 kuid_t uid; 277 } owner; 278 unsigned long lastuse; 279 unsigned long expires; 280 struct net *fl_net; 281 }; 282 283 #define IPV6_FLOWINFO_MASK cpu_to_be32(0x0FFFFFFF) 284 #define IPV6_FLOWLABEL_MASK cpu_to_be32(0x000FFFFF) 285 #define IPV6_FLOWLABEL_STATELESS_FLAG cpu_to_be32(0x00080000) 286 287 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK) 288 #define IPV6_TCLASS_SHIFT 20 289 290 struct ipv6_fl_socklist { 291 struct ipv6_fl_socklist __rcu *next; 292 struct ip6_flowlabel *fl; 293 struct rcu_head rcu; 294 }; 295 296 struct ipcm6_cookie { 297 struct sockcm_cookie sockc; 298 __s16 hlimit; 299 __s16 tclass; 300 __s8 dontfrag; 301 struct ipv6_txoptions *opt; 302 __u16 gso_size; 303 }; 304 305 static inline void ipcm6_init(struct ipcm6_cookie *ipc6) 306 { 307 *ipc6 = (struct ipcm6_cookie) { 308 .hlimit = -1, 309 .tclass = -1, 310 .dontfrag = -1, 311 }; 312 } 313 314 static inline void ipcm6_init_sk(struct ipcm6_cookie *ipc6, 315 const struct ipv6_pinfo *np) 316 { 317 *ipc6 = (struct ipcm6_cookie) { 318 .hlimit = -1, 319 .tclass = np->tclass, 320 .dontfrag = np->dontfrag, 321 }; 322 } 323 324 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np) 325 { 326 struct ipv6_txoptions *opt; 327 328 rcu_read_lock(); 329 opt = rcu_dereference(np->opt); 330 if (opt) { 331 if (!refcount_inc_not_zero(&opt->refcnt)) 332 opt = NULL; 333 else 334 opt = rcu_pointer_handoff(opt); 335 } 336 rcu_read_unlock(); 337 return opt; 338 } 339 340 static inline void txopt_put(struct ipv6_txoptions *opt) 341 { 342 if (opt && refcount_dec_and_test(&opt->refcnt)) 343 kfree_rcu(opt, rcu); 344 } 345 346 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label); 347 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 348 struct ip6_flowlabel *fl, 349 struct ipv6_txoptions *fopt); 350 void fl6_free_socklist(struct sock *sk); 351 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen); 352 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 353 int flags); 354 int ip6_flowlabel_init(void); 355 void ip6_flowlabel_cleanup(void); 356 bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np); 357 358 static inline void fl6_sock_release(struct ip6_flowlabel *fl) 359 { 360 if (fl) 361 atomic_dec(&fl->users); 362 } 363 364 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info); 365 366 void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, 367 struct icmp6hdr *thdr, int len); 368 369 int ip6_ra_control(struct sock *sk, int sel); 370 371 int ipv6_parse_hopopts(struct sk_buff *skb); 372 373 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk, 374 struct ipv6_txoptions *opt); 375 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk, 376 struct ipv6_txoptions *opt, 377 int newtype, 378 struct ipv6_opt_hdr *newopt); 379 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, 380 struct ipv6_txoptions *opt); 381 382 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb, 383 const struct inet6_skb_parm *opt); 384 struct ipv6_txoptions *ipv6_update_options(struct sock *sk, 385 struct ipv6_txoptions *opt); 386 387 static inline bool ipv6_accept_ra(struct inet6_dev *idev) 388 { 389 /* If forwarding is enabled, RA are not accepted unless the special 390 * hybrid mode (accept_ra=2) is enabled. 391 */ 392 return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 : 393 idev->cnf.accept_ra; 394 } 395 396 #define IPV6_FRAG_HIGH_THRESH (4 * 1024*1024) /* 4194304 */ 397 #define IPV6_FRAG_LOW_THRESH (3 * 1024*1024) /* 3145728 */ 398 #define IPV6_FRAG_TIMEOUT (60 * HZ) /* 60 seconds */ 399 400 int __ipv6_addr_type(const struct in6_addr *addr); 401 static inline int ipv6_addr_type(const struct in6_addr *addr) 402 { 403 return __ipv6_addr_type(addr) & 0xffff; 404 } 405 406 static inline int ipv6_addr_scope(const struct in6_addr *addr) 407 { 408 return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK; 409 } 410 411 static inline int __ipv6_addr_src_scope(int type) 412 { 413 return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16); 414 } 415 416 static inline int ipv6_addr_src_scope(const struct in6_addr *addr) 417 { 418 return __ipv6_addr_src_scope(__ipv6_addr_type(addr)); 419 } 420 421 static inline bool __ipv6_addr_needs_scope_id(int type) 422 { 423 return type & IPV6_ADDR_LINKLOCAL || 424 (type & IPV6_ADDR_MULTICAST && 425 (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL))); 426 } 427 428 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface) 429 { 430 return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0; 431 } 432 433 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2) 434 { 435 return memcmp(a1, a2, sizeof(struct in6_addr)); 436 } 437 438 static inline bool 439 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m, 440 const struct in6_addr *a2) 441 { 442 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 443 const unsigned long *ul1 = (const unsigned long *)a1; 444 const unsigned long *ulm = (const unsigned long *)m; 445 const unsigned long *ul2 = (const unsigned long *)a2; 446 447 return !!(((ul1[0] ^ ul2[0]) & ulm[0]) | 448 ((ul1[1] ^ ul2[1]) & ulm[1])); 449 #else 450 return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) | 451 ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) | 452 ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) | 453 ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3])); 454 #endif 455 } 456 457 static inline void ipv6_addr_prefix(struct in6_addr *pfx, 458 const struct in6_addr *addr, 459 int plen) 460 { 461 /* caller must guarantee 0 <= plen <= 128 */ 462 int o = plen >> 3, 463 b = plen & 0x7; 464 465 memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr)); 466 memcpy(pfx->s6_addr, addr, o); 467 if (b != 0) 468 pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b); 469 } 470 471 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr, 472 const struct in6_addr *pfx, 473 int plen) 474 { 475 /* caller must guarantee 0 <= plen <= 128 */ 476 int o = plen >> 3, 477 b = plen & 0x7; 478 479 memcpy(addr->s6_addr, pfx, o); 480 if (b != 0) { 481 addr->s6_addr[o] &= ~(0xff00 >> b); 482 addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b)); 483 } 484 } 485 486 static inline void __ipv6_addr_set_half(__be32 *addr, 487 __be32 wh, __be32 wl) 488 { 489 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 490 #if defined(__BIG_ENDIAN) 491 if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) { 492 *(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl)); 493 return; 494 } 495 #elif defined(__LITTLE_ENDIAN) 496 if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) { 497 *(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh)); 498 return; 499 } 500 #endif 501 #endif 502 addr[0] = wh; 503 addr[1] = wl; 504 } 505 506 static inline void ipv6_addr_set(struct in6_addr *addr, 507 __be32 w1, __be32 w2, 508 __be32 w3, __be32 w4) 509 { 510 __ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2); 511 __ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4); 512 } 513 514 static inline bool ipv6_addr_equal(const struct in6_addr *a1, 515 const struct in6_addr *a2) 516 { 517 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 518 const unsigned long *ul1 = (const unsigned long *)a1; 519 const unsigned long *ul2 = (const unsigned long *)a2; 520 521 return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL; 522 #else 523 return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) | 524 (a1->s6_addr32[1] ^ a2->s6_addr32[1]) | 525 (a1->s6_addr32[2] ^ a2->s6_addr32[2]) | 526 (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0; 527 #endif 528 } 529 530 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 531 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1, 532 const __be64 *a2, 533 unsigned int len) 534 { 535 if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len)))) 536 return false; 537 return true; 538 } 539 540 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1, 541 const struct in6_addr *addr2, 542 unsigned int prefixlen) 543 { 544 const __be64 *a1 = (const __be64 *)addr1; 545 const __be64 *a2 = (const __be64 *)addr2; 546 547 if (prefixlen >= 64) { 548 if (a1[0] ^ a2[0]) 549 return false; 550 return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64); 551 } 552 return __ipv6_prefix_equal64_half(a1, a2, prefixlen); 553 } 554 #else 555 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1, 556 const struct in6_addr *addr2, 557 unsigned int prefixlen) 558 { 559 const __be32 *a1 = addr1->s6_addr32; 560 const __be32 *a2 = addr2->s6_addr32; 561 unsigned int pdw, pbi; 562 563 /* check complete u32 in prefix */ 564 pdw = prefixlen >> 5; 565 if (pdw && memcmp(a1, a2, pdw << 2)) 566 return false; 567 568 /* check incomplete u32 in prefix */ 569 pbi = prefixlen & 0x1f; 570 if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi)))) 571 return false; 572 573 return true; 574 } 575 #endif 576 577 static inline bool ipv6_addr_any(const struct in6_addr *a) 578 { 579 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 580 const unsigned long *ul = (const unsigned long *)a; 581 582 return (ul[0] | ul[1]) == 0UL; 583 #else 584 return (a->s6_addr32[0] | a->s6_addr32[1] | 585 a->s6_addr32[2] | a->s6_addr32[3]) == 0; 586 #endif 587 } 588 589 static inline u32 ipv6_addr_hash(const struct in6_addr *a) 590 { 591 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 592 const unsigned long *ul = (const unsigned long *)a; 593 unsigned long x = ul[0] ^ ul[1]; 594 595 return (u32)(x ^ (x >> 32)); 596 #else 597 return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^ 598 a->s6_addr32[2] ^ a->s6_addr32[3]); 599 #endif 600 } 601 602 /* more secured version of ipv6_addr_hash() */ 603 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval) 604 { 605 u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1]; 606 607 return jhash_3words(v, 608 (__force u32)a->s6_addr32[2], 609 (__force u32)a->s6_addr32[3], 610 initval); 611 } 612 613 static inline bool ipv6_addr_loopback(const struct in6_addr *a) 614 { 615 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 616 const __be64 *be = (const __be64 *)a; 617 618 return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL; 619 #else 620 return (a->s6_addr32[0] | a->s6_addr32[1] | 621 a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0; 622 #endif 623 } 624 625 /* 626 * Note that we must __force cast these to unsigned long to make sparse happy, 627 * since all of the endian-annotated types are fixed size regardless of arch. 628 */ 629 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a) 630 { 631 return ( 632 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 633 *(unsigned long *)a | 634 #else 635 (__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) | 636 #endif 637 (__force unsigned long)(a->s6_addr32[2] ^ 638 cpu_to_be32(0x0000ffff))) == 0UL; 639 } 640 641 static inline u32 ipv6_portaddr_hash(const struct net *net, 642 const struct in6_addr *addr6, 643 unsigned int port) 644 { 645 unsigned int hash, mix = net_hash_mix(net); 646 647 if (ipv6_addr_any(addr6)) 648 hash = jhash_1word(0, mix); 649 else if (ipv6_addr_v4mapped(addr6)) 650 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix); 651 else 652 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix); 653 654 return hash ^ port; 655 } 656 657 /* 658 * Check for a RFC 4843 ORCHID address 659 * (Overlay Routable Cryptographic Hash Identifiers) 660 */ 661 static inline bool ipv6_addr_orchid(const struct in6_addr *a) 662 { 663 return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010); 664 } 665 666 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr) 667 { 668 return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000); 669 } 670 671 static inline void ipv6_addr_set_v4mapped(const __be32 addr, 672 struct in6_addr *v4mapped) 673 { 674 ipv6_addr_set(v4mapped, 675 0, 0, 676 htonl(0x0000FFFF), 677 addr); 678 } 679 680 /* 681 * find the first different bit between two addresses 682 * length of address must be a multiple of 32bits 683 */ 684 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen) 685 { 686 const __be32 *a1 = token1, *a2 = token2; 687 int i; 688 689 addrlen >>= 2; 690 691 for (i = 0; i < addrlen; i++) { 692 __be32 xb = a1[i] ^ a2[i]; 693 if (xb) 694 return i * 32 + 31 - __fls(ntohl(xb)); 695 } 696 697 /* 698 * we should *never* get to this point since that 699 * would mean the addrs are equal 700 * 701 * However, we do get to it 8) And exacly, when 702 * addresses are equal 8) 703 * 704 * ip route add 1111::/128 via ... 705 * ip route add 1111::/64 via ... 706 * and we are here. 707 * 708 * Ideally, this function should stop comparison 709 * at prefix length. It does not, but it is still OK, 710 * if returned value is greater than prefix length. 711 * --ANK (980803) 712 */ 713 return addrlen << 5; 714 } 715 716 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 717 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen) 718 { 719 const __be64 *a1 = token1, *a2 = token2; 720 int i; 721 722 addrlen >>= 3; 723 724 for (i = 0; i < addrlen; i++) { 725 __be64 xb = a1[i] ^ a2[i]; 726 if (xb) 727 return i * 64 + 63 - __fls(be64_to_cpu(xb)); 728 } 729 730 return addrlen << 6; 731 } 732 #endif 733 734 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen) 735 { 736 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 737 if (__builtin_constant_p(addrlen) && !(addrlen & 7)) 738 return __ipv6_addr_diff64(token1, token2, addrlen); 739 #endif 740 return __ipv6_addr_diff32(token1, token2, addrlen); 741 } 742 743 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2) 744 { 745 return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr)); 746 } 747 748 __be32 ipv6_select_ident(struct net *net, 749 const struct in6_addr *daddr, 750 const struct in6_addr *saddr); 751 __be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb); 752 753 int ip6_dst_hoplimit(struct dst_entry *dst); 754 755 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6, 756 struct dst_entry *dst) 757 { 758 int hlimit; 759 760 if (ipv6_addr_is_multicast(&fl6->daddr)) 761 hlimit = np->mcast_hops; 762 else 763 hlimit = np->hop_limit; 764 if (hlimit < 0) 765 hlimit = ip6_dst_hoplimit(dst); 766 return hlimit; 767 } 768 769 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store 770 * Equivalent to : flow->v6addrs.src = iph->saddr; 771 * flow->v6addrs.dst = iph->daddr; 772 */ 773 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow, 774 const struct ipv6hdr *iph) 775 { 776 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) != 777 offsetof(typeof(flow->addrs), v6addrs.src) + 778 sizeof(flow->addrs.v6addrs.src)); 779 memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs)); 780 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; 781 } 782 783 #if IS_ENABLED(CONFIG_IPV6) 784 785 static inline bool ipv6_can_nonlocal_bind(struct net *net, 786 struct inet_sock *inet) 787 { 788 return net->ipv6.sysctl.ip_nonlocal_bind || 789 inet->freebind || inet->transparent; 790 } 791 792 /* Sysctl settings for net ipv6.auto_flowlabels */ 793 #define IP6_AUTO_FLOW_LABEL_OFF 0 794 #define IP6_AUTO_FLOW_LABEL_OPTOUT 1 795 #define IP6_AUTO_FLOW_LABEL_OPTIN 2 796 #define IP6_AUTO_FLOW_LABEL_FORCED 3 797 798 #define IP6_AUTO_FLOW_LABEL_MAX IP6_AUTO_FLOW_LABEL_FORCED 799 800 #define IP6_DEFAULT_AUTO_FLOW_LABELS IP6_AUTO_FLOW_LABEL_OPTOUT 801 802 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, 803 __be32 flowlabel, bool autolabel, 804 struct flowi6 *fl6) 805 { 806 u32 hash; 807 808 /* @flowlabel may include more than a flow label, eg, the traffic class. 809 * Here we want only the flow label value. 810 */ 811 flowlabel &= IPV6_FLOWLABEL_MASK; 812 813 if (flowlabel || 814 net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF || 815 (!autolabel && 816 net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED)) 817 return flowlabel; 818 819 hash = skb_get_hash_flowi6(skb, fl6); 820 821 /* Since this is being sent on the wire obfuscate hash a bit 822 * to minimize possbility that any useful information to an 823 * attacker is leaked. Only lower 20 bits are relevant. 824 */ 825 hash = rol32(hash, 16); 826 827 flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK; 828 829 if (net->ipv6.sysctl.flowlabel_state_ranges) 830 flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG; 831 832 return flowlabel; 833 } 834 835 static inline int ip6_default_np_autolabel(struct net *net) 836 { 837 switch (net->ipv6.sysctl.auto_flowlabels) { 838 case IP6_AUTO_FLOW_LABEL_OFF: 839 case IP6_AUTO_FLOW_LABEL_OPTIN: 840 default: 841 return 0; 842 case IP6_AUTO_FLOW_LABEL_OPTOUT: 843 case IP6_AUTO_FLOW_LABEL_FORCED: 844 return 1; 845 } 846 } 847 #else 848 static inline void ip6_set_txhash(struct sock *sk) { } 849 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, 850 __be32 flowlabel, bool autolabel, 851 struct flowi6 *fl6) 852 { 853 return flowlabel; 854 } 855 static inline int ip6_default_np_autolabel(struct net *net) 856 { 857 return 0; 858 } 859 #endif 860 861 #if IS_ENABLED(CONFIG_IPV6) 862 static inline int ip6_multipath_hash_policy(const struct net *net) 863 { 864 return net->ipv6.sysctl.multipath_hash_policy; 865 } 866 #else 867 static inline int ip6_multipath_hash_policy(const struct net *net) 868 { 869 return 0; 870 } 871 #endif 872 873 /* 874 * Header manipulation 875 */ 876 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass, 877 __be32 flowlabel) 878 { 879 *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel; 880 } 881 882 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr) 883 { 884 return *(__be32 *)hdr & IPV6_FLOWINFO_MASK; 885 } 886 887 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr) 888 { 889 return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK; 890 } 891 892 static inline u8 ip6_tclass(__be32 flowinfo) 893 { 894 return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT; 895 } 896 897 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel) 898 { 899 return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel; 900 } 901 902 static inline __be32 flowi6_get_flowlabel(const struct flowi6 *fl6) 903 { 904 return fl6->flowlabel & IPV6_FLOWLABEL_MASK; 905 } 906 907 /* 908 * Prototypes exported by ipv6 909 */ 910 911 /* 912 * rcv function (called from netdevice level) 913 */ 914 915 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, 916 struct packet_type *pt, struct net_device *orig_dev); 917 void ipv6_list_rcv(struct list_head *head, struct packet_type *pt, 918 struct net_device *orig_dev); 919 920 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb); 921 922 /* 923 * upper-layer output functions 924 */ 925 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, 926 __u32 mark, struct ipv6_txoptions *opt, int tclass); 927 928 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr); 929 930 int ip6_append_data(struct sock *sk, 931 int getfrag(void *from, char *to, int offset, int len, 932 int odd, struct sk_buff *skb), 933 void *from, int length, int transhdrlen, 934 struct ipcm6_cookie *ipc6, struct flowi6 *fl6, 935 struct rt6_info *rt, unsigned int flags); 936 937 int ip6_push_pending_frames(struct sock *sk); 938 939 void ip6_flush_pending_frames(struct sock *sk); 940 941 int ip6_send_skb(struct sk_buff *skb); 942 943 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue, 944 struct inet_cork_full *cork, 945 struct inet6_cork *v6_cork); 946 struct sk_buff *ip6_make_skb(struct sock *sk, 947 int getfrag(void *from, char *to, int offset, 948 int len, int odd, struct sk_buff *skb), 949 void *from, int length, int transhdrlen, 950 struct ipcm6_cookie *ipc6, struct flowi6 *fl6, 951 struct rt6_info *rt, unsigned int flags, 952 struct inet_cork_full *cork); 953 954 static inline struct sk_buff *ip6_finish_skb(struct sock *sk) 955 { 956 return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork, 957 &inet6_sk(sk)->cork); 958 } 959 960 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst, 961 struct flowi6 *fl6); 962 struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6, 963 const struct in6_addr *final_dst); 964 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6, 965 const struct in6_addr *final_dst, 966 bool connected); 967 struct dst_entry *ip6_blackhole_route(struct net *net, 968 struct dst_entry *orig_dst); 969 970 /* 971 * skb processing functions 972 */ 973 974 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb); 975 int ip6_forward(struct sk_buff *skb); 976 int ip6_input(struct sk_buff *skb); 977 int ip6_mc_input(struct sk_buff *skb); 978 979 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 980 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 981 982 /* 983 * Extension header (options) processing 984 */ 985 986 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, 987 u8 *proto, struct in6_addr **daddr_p, 988 struct in6_addr *saddr); 989 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, 990 u8 *proto); 991 992 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp, 993 __be16 *frag_offp); 994 995 bool ipv6_ext_hdr(u8 nexthdr); 996 997 enum { 998 IP6_FH_F_FRAG = (1 << 0), 999 IP6_FH_F_AUTH = (1 << 1), 1000 IP6_FH_F_SKIP_RH = (1 << 2), 1001 }; 1002 1003 /* find specified header and get offset to it */ 1004 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target, 1005 unsigned short *fragoff, int *fragflg); 1006 1007 int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type); 1008 1009 struct in6_addr *fl6_update_dst(struct flowi6 *fl6, 1010 const struct ipv6_txoptions *opt, 1011 struct in6_addr *orig); 1012 1013 /* 1014 * socket options (ipv6_sockglue.c) 1015 */ 1016 1017 int ipv6_setsockopt(struct sock *sk, int level, int optname, 1018 char __user *optval, unsigned int optlen); 1019 int ipv6_getsockopt(struct sock *sk, int level, int optname, 1020 char __user *optval, int __user *optlen); 1021 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname, 1022 char __user *optval, unsigned int optlen); 1023 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname, 1024 char __user *optval, int __user *optlen); 1025 1026 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, 1027 int addr_len); 1028 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len); 1029 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr, 1030 int addr_len); 1031 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr); 1032 void ip6_datagram_release_cb(struct sock *sk); 1033 1034 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, 1035 int *addr_len); 1036 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len, 1037 int *addr_len); 1038 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 1039 u32 info, u8 *payload); 1040 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info); 1041 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu); 1042 1043 int inet6_release(struct socket *sock); 1044 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len); 1045 int inet6_getname(struct socket *sock, struct sockaddr *uaddr, 1046 int peer); 1047 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg); 1048 1049 int inet6_hash_connect(struct inet_timewait_death_row *death_row, 1050 struct sock *sk); 1051 1052 /* 1053 * reassembly.c 1054 */ 1055 extern const struct proto_ops inet6_stream_ops; 1056 extern const struct proto_ops inet6_dgram_ops; 1057 extern const struct proto_ops inet6_sockraw_ops; 1058 1059 struct group_source_req; 1060 struct group_filter; 1061 1062 int ip6_mc_source(int add, int omode, struct sock *sk, 1063 struct group_source_req *pgsr); 1064 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf); 1065 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, 1066 struct group_filter __user *optval, int __user *optlen); 1067 1068 #ifdef CONFIG_PROC_FS 1069 int ac6_proc_init(struct net *net); 1070 void ac6_proc_exit(struct net *net); 1071 int raw6_proc_init(void); 1072 void raw6_proc_exit(void); 1073 int tcp6_proc_init(struct net *net); 1074 void tcp6_proc_exit(struct net *net); 1075 int udp6_proc_init(struct net *net); 1076 void udp6_proc_exit(struct net *net); 1077 int udplite6_proc_init(void); 1078 void udplite6_proc_exit(void); 1079 int ipv6_misc_proc_init(void); 1080 void ipv6_misc_proc_exit(void); 1081 int snmp6_register_dev(struct inet6_dev *idev); 1082 int snmp6_unregister_dev(struct inet6_dev *idev); 1083 1084 #else 1085 static inline int ac6_proc_init(struct net *net) { return 0; } 1086 static inline void ac6_proc_exit(struct net *net) { } 1087 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; } 1088 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; } 1089 #endif 1090 1091 #ifdef CONFIG_SYSCTL 1092 extern struct ctl_table ipv6_route_table_template[]; 1093 1094 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net); 1095 struct ctl_table *ipv6_route_sysctl_init(struct net *net); 1096 int ipv6_sysctl_register(void); 1097 void ipv6_sysctl_unregister(void); 1098 #endif 1099 1100 int ipv6_sock_mc_join(struct sock *sk, int ifindex, 1101 const struct in6_addr *addr); 1102 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex, 1103 const struct in6_addr *addr, unsigned int mode); 1104 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, 1105 const struct in6_addr *addr); 1106 #endif /* _NET_IPV6_H */ 1107