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 __s16 hlimit; 298 __s16 tclass; 299 __s8 dontfrag; 300 struct ipv6_txoptions *opt; 301 }; 302 303 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np) 304 { 305 struct ipv6_txoptions *opt; 306 307 rcu_read_lock(); 308 opt = rcu_dereference(np->opt); 309 if (opt) { 310 if (!refcount_inc_not_zero(&opt->refcnt)) 311 opt = NULL; 312 else 313 opt = rcu_pointer_handoff(opt); 314 } 315 rcu_read_unlock(); 316 return opt; 317 } 318 319 static inline void txopt_put(struct ipv6_txoptions *opt) 320 { 321 if (opt && refcount_dec_and_test(&opt->refcnt)) 322 kfree_rcu(opt, rcu); 323 } 324 325 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label); 326 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 327 struct ip6_flowlabel *fl, 328 struct ipv6_txoptions *fopt); 329 void fl6_free_socklist(struct sock *sk); 330 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen); 331 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 332 int flags); 333 int ip6_flowlabel_init(void); 334 void ip6_flowlabel_cleanup(void); 335 336 static inline void fl6_sock_release(struct ip6_flowlabel *fl) 337 { 338 if (fl) 339 atomic_dec(&fl->users); 340 } 341 342 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info); 343 344 void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, 345 struct icmp6hdr *thdr, int len); 346 347 int ip6_ra_control(struct sock *sk, int sel); 348 349 int ipv6_parse_hopopts(struct sk_buff *skb); 350 351 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk, 352 struct ipv6_txoptions *opt); 353 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk, 354 struct ipv6_txoptions *opt, 355 int newtype, 356 struct ipv6_opt_hdr __user *newopt, 357 int newoptlen); 358 struct ipv6_txoptions * 359 ipv6_renew_options_kern(struct sock *sk, 360 struct ipv6_txoptions *opt, 361 int newtype, 362 struct ipv6_opt_hdr *newopt, 363 int newoptlen); 364 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, 365 struct ipv6_txoptions *opt); 366 367 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb, 368 const struct inet6_skb_parm *opt); 369 struct ipv6_txoptions *ipv6_update_options(struct sock *sk, 370 struct ipv6_txoptions *opt); 371 372 static inline bool ipv6_accept_ra(struct inet6_dev *idev) 373 { 374 /* If forwarding is enabled, RA are not accepted unless the special 375 * hybrid mode (accept_ra=2) is enabled. 376 */ 377 return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 : 378 idev->cnf.accept_ra; 379 } 380 381 #if IS_ENABLED(CONFIG_IPV6) 382 static inline int ip6_frag_mem(struct net *net) 383 { 384 return sum_frag_mem_limit(&net->ipv6.frags); 385 } 386 #endif 387 388 #define IPV6_FRAG_HIGH_THRESH (4 * 1024*1024) /* 4194304 */ 389 #define IPV6_FRAG_LOW_THRESH (3 * 1024*1024) /* 3145728 */ 390 #define IPV6_FRAG_TIMEOUT (60 * HZ) /* 60 seconds */ 391 392 int __ipv6_addr_type(const struct in6_addr *addr); 393 static inline int ipv6_addr_type(const struct in6_addr *addr) 394 { 395 return __ipv6_addr_type(addr) & 0xffff; 396 } 397 398 static inline int ipv6_addr_scope(const struct in6_addr *addr) 399 { 400 return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK; 401 } 402 403 static inline int __ipv6_addr_src_scope(int type) 404 { 405 return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16); 406 } 407 408 static inline int ipv6_addr_src_scope(const struct in6_addr *addr) 409 { 410 return __ipv6_addr_src_scope(__ipv6_addr_type(addr)); 411 } 412 413 static inline bool __ipv6_addr_needs_scope_id(int type) 414 { 415 return type & IPV6_ADDR_LINKLOCAL || 416 (type & IPV6_ADDR_MULTICAST && 417 (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL))); 418 } 419 420 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface) 421 { 422 return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0; 423 } 424 425 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2) 426 { 427 return memcmp(a1, a2, sizeof(struct in6_addr)); 428 } 429 430 static inline bool 431 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m, 432 const struct in6_addr *a2) 433 { 434 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 435 const unsigned long *ul1 = (const unsigned long *)a1; 436 const unsigned long *ulm = (const unsigned long *)m; 437 const unsigned long *ul2 = (const unsigned long *)a2; 438 439 return !!(((ul1[0] ^ ul2[0]) & ulm[0]) | 440 ((ul1[1] ^ ul2[1]) & ulm[1])); 441 #else 442 return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) | 443 ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) | 444 ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) | 445 ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3])); 446 #endif 447 } 448 449 static inline void ipv6_addr_prefix(struct in6_addr *pfx, 450 const struct in6_addr *addr, 451 int plen) 452 { 453 /* caller must guarantee 0 <= plen <= 128 */ 454 int o = plen >> 3, 455 b = plen & 0x7; 456 457 memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr)); 458 memcpy(pfx->s6_addr, addr, o); 459 if (b != 0) 460 pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b); 461 } 462 463 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr, 464 const struct in6_addr *pfx, 465 int plen) 466 { 467 /* caller must guarantee 0 <= plen <= 128 */ 468 int o = plen >> 3, 469 b = plen & 0x7; 470 471 memcpy(addr->s6_addr, pfx, o); 472 if (b != 0) { 473 addr->s6_addr[o] &= ~(0xff00 >> b); 474 addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b)); 475 } 476 } 477 478 static inline void __ipv6_addr_set_half(__be32 *addr, 479 __be32 wh, __be32 wl) 480 { 481 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 482 #if defined(__BIG_ENDIAN) 483 if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) { 484 *(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl)); 485 return; 486 } 487 #elif defined(__LITTLE_ENDIAN) 488 if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) { 489 *(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh)); 490 return; 491 } 492 #endif 493 #endif 494 addr[0] = wh; 495 addr[1] = wl; 496 } 497 498 static inline void ipv6_addr_set(struct in6_addr *addr, 499 __be32 w1, __be32 w2, 500 __be32 w3, __be32 w4) 501 { 502 __ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2); 503 __ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4); 504 } 505 506 static inline bool ipv6_addr_equal(const struct in6_addr *a1, 507 const struct in6_addr *a2) 508 { 509 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 510 const unsigned long *ul1 = (const unsigned long *)a1; 511 const unsigned long *ul2 = (const unsigned long *)a2; 512 513 return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL; 514 #else 515 return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) | 516 (a1->s6_addr32[1] ^ a2->s6_addr32[1]) | 517 (a1->s6_addr32[2] ^ a2->s6_addr32[2]) | 518 (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0; 519 #endif 520 } 521 522 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 523 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1, 524 const __be64 *a2, 525 unsigned int len) 526 { 527 if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len)))) 528 return false; 529 return true; 530 } 531 532 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1, 533 const struct in6_addr *addr2, 534 unsigned int prefixlen) 535 { 536 const __be64 *a1 = (const __be64 *)addr1; 537 const __be64 *a2 = (const __be64 *)addr2; 538 539 if (prefixlen >= 64) { 540 if (a1[0] ^ a2[0]) 541 return false; 542 return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64); 543 } 544 return __ipv6_prefix_equal64_half(a1, a2, prefixlen); 545 } 546 #else 547 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1, 548 const struct in6_addr *addr2, 549 unsigned int prefixlen) 550 { 551 const __be32 *a1 = addr1->s6_addr32; 552 const __be32 *a2 = addr2->s6_addr32; 553 unsigned int pdw, pbi; 554 555 /* check complete u32 in prefix */ 556 pdw = prefixlen >> 5; 557 if (pdw && memcmp(a1, a2, pdw << 2)) 558 return false; 559 560 /* check incomplete u32 in prefix */ 561 pbi = prefixlen & 0x1f; 562 if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi)))) 563 return false; 564 565 return true; 566 } 567 #endif 568 569 struct inet_frag_queue; 570 571 enum ip6_defrag_users { 572 IP6_DEFRAG_LOCAL_DELIVER, 573 IP6_DEFRAG_CONNTRACK_IN, 574 __IP6_DEFRAG_CONNTRACK_IN = IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX, 575 IP6_DEFRAG_CONNTRACK_OUT, 576 __IP6_DEFRAG_CONNTRACK_OUT = IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX, 577 IP6_DEFRAG_CONNTRACK_BRIDGE_IN, 578 __IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX, 579 }; 580 581 struct ip6_create_arg { 582 __be32 id; 583 u32 user; 584 const struct in6_addr *src; 585 const struct in6_addr *dst; 586 int iif; 587 u8 ecn; 588 }; 589 590 void ip6_frag_init(struct inet_frag_queue *q, const void *a); 591 bool ip6_frag_match(const struct inet_frag_queue *q, const void *a); 592 593 /* 594 * Equivalent of ipv4 struct ip 595 */ 596 struct frag_queue { 597 struct inet_frag_queue q; 598 599 __be32 id; /* fragment id */ 600 u32 user; 601 struct in6_addr saddr; 602 struct in6_addr daddr; 603 604 int iif; 605 unsigned int csum; 606 __u16 nhoffset; 607 u8 ecn; 608 }; 609 610 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq, 611 struct inet_frags *frags); 612 613 static inline bool ipv6_addr_any(const struct in6_addr *a) 614 { 615 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 616 const unsigned long *ul = (const unsigned long *)a; 617 618 return (ul[0] | ul[1]) == 0UL; 619 #else 620 return (a->s6_addr32[0] | a->s6_addr32[1] | 621 a->s6_addr32[2] | a->s6_addr32[3]) == 0; 622 #endif 623 } 624 625 static inline u32 ipv6_addr_hash(const struct in6_addr *a) 626 { 627 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 628 const unsigned long *ul = (const unsigned long *)a; 629 unsigned long x = ul[0] ^ ul[1]; 630 631 return (u32)(x ^ (x >> 32)); 632 #else 633 return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^ 634 a->s6_addr32[2] ^ a->s6_addr32[3]); 635 #endif 636 } 637 638 /* more secured version of ipv6_addr_hash() */ 639 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval) 640 { 641 u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1]; 642 643 return jhash_3words(v, 644 (__force u32)a->s6_addr32[2], 645 (__force u32)a->s6_addr32[3], 646 initval); 647 } 648 649 static inline bool ipv6_addr_loopback(const struct in6_addr *a) 650 { 651 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 652 const __be64 *be = (const __be64 *)a; 653 654 return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL; 655 #else 656 return (a->s6_addr32[0] | a->s6_addr32[1] | 657 a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0; 658 #endif 659 } 660 661 /* 662 * Note that we must __force cast these to unsigned long to make sparse happy, 663 * since all of the endian-annotated types are fixed size regardless of arch. 664 */ 665 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a) 666 { 667 return ( 668 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 669 *(unsigned long *)a | 670 #else 671 (__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) | 672 #endif 673 (__force unsigned long)(a->s6_addr32[2] ^ 674 cpu_to_be32(0x0000ffff))) == 0UL; 675 } 676 677 static inline u32 ipv6_portaddr_hash(const struct net *net, 678 const struct in6_addr *addr6, 679 unsigned int port) 680 { 681 unsigned int hash, mix = net_hash_mix(net); 682 683 if (ipv6_addr_any(addr6)) 684 hash = jhash_1word(0, mix); 685 else if (ipv6_addr_v4mapped(addr6)) 686 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix); 687 else 688 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix); 689 690 return hash ^ port; 691 } 692 693 /* 694 * Check for a RFC 4843 ORCHID address 695 * (Overlay Routable Cryptographic Hash Identifiers) 696 */ 697 static inline bool ipv6_addr_orchid(const struct in6_addr *a) 698 { 699 return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010); 700 } 701 702 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr) 703 { 704 return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000); 705 } 706 707 static inline void ipv6_addr_set_v4mapped(const __be32 addr, 708 struct in6_addr *v4mapped) 709 { 710 ipv6_addr_set(v4mapped, 711 0, 0, 712 htonl(0x0000FFFF), 713 addr); 714 } 715 716 /* 717 * find the first different bit between two addresses 718 * length of address must be a multiple of 32bits 719 */ 720 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen) 721 { 722 const __be32 *a1 = token1, *a2 = token2; 723 int i; 724 725 addrlen >>= 2; 726 727 for (i = 0; i < addrlen; i++) { 728 __be32 xb = a1[i] ^ a2[i]; 729 if (xb) 730 return i * 32 + 31 - __fls(ntohl(xb)); 731 } 732 733 /* 734 * we should *never* get to this point since that 735 * would mean the addrs are equal 736 * 737 * However, we do get to it 8) And exacly, when 738 * addresses are equal 8) 739 * 740 * ip route add 1111::/128 via ... 741 * ip route add 1111::/64 via ... 742 * and we are here. 743 * 744 * Ideally, this function should stop comparison 745 * at prefix length. It does not, but it is still OK, 746 * if returned value is greater than prefix length. 747 * --ANK (980803) 748 */ 749 return addrlen << 5; 750 } 751 752 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 753 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen) 754 { 755 const __be64 *a1 = token1, *a2 = token2; 756 int i; 757 758 addrlen >>= 3; 759 760 for (i = 0; i < addrlen; i++) { 761 __be64 xb = a1[i] ^ a2[i]; 762 if (xb) 763 return i * 64 + 63 - __fls(be64_to_cpu(xb)); 764 } 765 766 return addrlen << 6; 767 } 768 #endif 769 770 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen) 771 { 772 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 773 if (__builtin_constant_p(addrlen) && !(addrlen & 7)) 774 return __ipv6_addr_diff64(token1, token2, addrlen); 775 #endif 776 return __ipv6_addr_diff32(token1, token2, addrlen); 777 } 778 779 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2) 780 { 781 return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr)); 782 } 783 784 __be32 ipv6_select_ident(struct net *net, 785 const struct in6_addr *daddr, 786 const struct in6_addr *saddr); 787 __be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb); 788 789 int ip6_dst_hoplimit(struct dst_entry *dst); 790 791 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6, 792 struct dst_entry *dst) 793 { 794 int hlimit; 795 796 if (ipv6_addr_is_multicast(&fl6->daddr)) 797 hlimit = np->mcast_hops; 798 else 799 hlimit = np->hop_limit; 800 if (hlimit < 0) 801 hlimit = ip6_dst_hoplimit(dst); 802 return hlimit; 803 } 804 805 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store 806 * Equivalent to : flow->v6addrs.src = iph->saddr; 807 * flow->v6addrs.dst = iph->daddr; 808 */ 809 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow, 810 const struct ipv6hdr *iph) 811 { 812 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) != 813 offsetof(typeof(flow->addrs), v6addrs.src) + 814 sizeof(flow->addrs.v6addrs.src)); 815 memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs)); 816 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; 817 } 818 819 #if IS_ENABLED(CONFIG_IPV6) 820 821 /* Sysctl settings for net ipv6.auto_flowlabels */ 822 #define IP6_AUTO_FLOW_LABEL_OFF 0 823 #define IP6_AUTO_FLOW_LABEL_OPTOUT 1 824 #define IP6_AUTO_FLOW_LABEL_OPTIN 2 825 #define IP6_AUTO_FLOW_LABEL_FORCED 3 826 827 #define IP6_AUTO_FLOW_LABEL_MAX IP6_AUTO_FLOW_LABEL_FORCED 828 829 #define IP6_DEFAULT_AUTO_FLOW_LABELS IP6_AUTO_FLOW_LABEL_OPTOUT 830 831 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, 832 __be32 flowlabel, bool autolabel, 833 struct flowi6 *fl6) 834 { 835 u32 hash; 836 837 /* @flowlabel may include more than a flow label, eg, the traffic class. 838 * Here we want only the flow label value. 839 */ 840 flowlabel &= IPV6_FLOWLABEL_MASK; 841 842 if (flowlabel || 843 net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF || 844 (!autolabel && 845 net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED)) 846 return flowlabel; 847 848 hash = skb_get_hash_flowi6(skb, fl6); 849 850 /* Since this is being sent on the wire obfuscate hash a bit 851 * to minimize possbility that any useful information to an 852 * attacker is leaked. Only lower 20 bits are relevant. 853 */ 854 rol32(hash, 16); 855 856 flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK; 857 858 if (net->ipv6.sysctl.flowlabel_state_ranges) 859 flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG; 860 861 return flowlabel; 862 } 863 864 static inline int ip6_default_np_autolabel(struct net *net) 865 { 866 switch (net->ipv6.sysctl.auto_flowlabels) { 867 case IP6_AUTO_FLOW_LABEL_OFF: 868 case IP6_AUTO_FLOW_LABEL_OPTIN: 869 default: 870 return 0; 871 case IP6_AUTO_FLOW_LABEL_OPTOUT: 872 case IP6_AUTO_FLOW_LABEL_FORCED: 873 return 1; 874 } 875 } 876 #else 877 static inline void ip6_set_txhash(struct sock *sk) { } 878 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, 879 __be32 flowlabel, bool autolabel, 880 struct flowi6 *fl6) 881 { 882 return flowlabel; 883 } 884 static inline int ip6_default_np_autolabel(struct net *net) 885 { 886 return 0; 887 } 888 #endif 889 890 891 /* 892 * Header manipulation 893 */ 894 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass, 895 __be32 flowlabel) 896 { 897 *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel; 898 } 899 900 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr) 901 { 902 return *(__be32 *)hdr & IPV6_FLOWINFO_MASK; 903 } 904 905 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr) 906 { 907 return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK; 908 } 909 910 static inline u8 ip6_tclass(__be32 flowinfo) 911 { 912 return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT; 913 } 914 915 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel) 916 { 917 return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel; 918 } 919 920 /* 921 * Prototypes exported by ipv6 922 */ 923 924 /* 925 * rcv function (called from netdevice level) 926 */ 927 928 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, 929 struct packet_type *pt, struct net_device *orig_dev); 930 931 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb); 932 933 /* 934 * upper-layer output functions 935 */ 936 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, 937 __u32 mark, struct ipv6_txoptions *opt, int tclass); 938 939 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr); 940 941 int ip6_append_data(struct sock *sk, 942 int getfrag(void *from, char *to, int offset, int len, 943 int odd, struct sk_buff *skb), 944 void *from, int length, int transhdrlen, 945 struct ipcm6_cookie *ipc6, struct flowi6 *fl6, 946 struct rt6_info *rt, unsigned int flags, 947 const struct sockcm_cookie *sockc); 948 949 int ip6_push_pending_frames(struct sock *sk); 950 951 void ip6_flush_pending_frames(struct sock *sk); 952 953 int ip6_send_skb(struct sk_buff *skb); 954 955 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue, 956 struct inet_cork_full *cork, 957 struct inet6_cork *v6_cork); 958 struct sk_buff *ip6_make_skb(struct sock *sk, 959 int getfrag(void *from, char *to, int offset, 960 int len, int odd, struct sk_buff *skb), 961 void *from, int length, int transhdrlen, 962 struct ipcm6_cookie *ipc6, struct flowi6 *fl6, 963 struct rt6_info *rt, unsigned int flags, 964 const struct sockcm_cookie *sockc); 965 966 static inline struct sk_buff *ip6_finish_skb(struct sock *sk) 967 { 968 return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork, 969 &inet6_sk(sk)->cork); 970 } 971 972 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst, 973 struct flowi6 *fl6); 974 struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6, 975 const struct in6_addr *final_dst); 976 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6, 977 const struct in6_addr *final_dst); 978 struct dst_entry *ip6_blackhole_route(struct net *net, 979 struct dst_entry *orig_dst); 980 981 /* 982 * skb processing functions 983 */ 984 985 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb); 986 int ip6_forward(struct sk_buff *skb); 987 int ip6_input(struct sk_buff *skb); 988 int ip6_mc_input(struct sk_buff *skb); 989 990 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 991 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 992 993 /* 994 * Extension header (options) processing 995 */ 996 997 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, 998 u8 *proto, struct in6_addr **daddr_p, 999 struct in6_addr *saddr); 1000 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, 1001 u8 *proto); 1002 1003 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp, 1004 __be16 *frag_offp); 1005 1006 bool ipv6_ext_hdr(u8 nexthdr); 1007 1008 enum { 1009 IP6_FH_F_FRAG = (1 << 0), 1010 IP6_FH_F_AUTH = (1 << 1), 1011 IP6_FH_F_SKIP_RH = (1 << 2), 1012 }; 1013 1014 /* find specified header and get offset to it */ 1015 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target, 1016 unsigned short *fragoff, int *fragflg); 1017 1018 int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type); 1019 1020 struct in6_addr *fl6_update_dst(struct flowi6 *fl6, 1021 const struct ipv6_txoptions *opt, 1022 struct in6_addr *orig); 1023 1024 /* 1025 * socket options (ipv6_sockglue.c) 1026 */ 1027 1028 int ipv6_setsockopt(struct sock *sk, int level, int optname, 1029 char __user *optval, unsigned int optlen); 1030 int ipv6_getsockopt(struct sock *sk, int level, int optname, 1031 char __user *optval, int __user *optlen); 1032 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname, 1033 char __user *optval, unsigned int optlen); 1034 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname, 1035 char __user *optval, int __user *optlen); 1036 1037 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, 1038 int addr_len); 1039 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len); 1040 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr, 1041 int addr_len); 1042 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr); 1043 void ip6_datagram_release_cb(struct sock *sk); 1044 1045 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, 1046 int *addr_len); 1047 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len, 1048 int *addr_len); 1049 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 1050 u32 info, u8 *payload); 1051 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info); 1052 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu); 1053 1054 int inet6_release(struct socket *sock); 1055 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len); 1056 int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, 1057 int peer); 1058 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg); 1059 1060 int inet6_hash_connect(struct inet_timewait_death_row *death_row, 1061 struct sock *sk); 1062 1063 /* 1064 * reassembly.c 1065 */ 1066 extern const struct proto_ops inet6_stream_ops; 1067 extern const struct proto_ops inet6_dgram_ops; 1068 extern const struct proto_ops inet6_sockraw_ops; 1069 1070 struct group_source_req; 1071 struct group_filter; 1072 1073 int ip6_mc_source(int add, int omode, struct sock *sk, 1074 struct group_source_req *pgsr); 1075 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf); 1076 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, 1077 struct group_filter __user *optval, int __user *optlen); 1078 1079 #ifdef CONFIG_PROC_FS 1080 int ac6_proc_init(struct net *net); 1081 void ac6_proc_exit(struct net *net); 1082 int raw6_proc_init(void); 1083 void raw6_proc_exit(void); 1084 int tcp6_proc_init(struct net *net); 1085 void tcp6_proc_exit(struct net *net); 1086 int udp6_proc_init(struct net *net); 1087 void udp6_proc_exit(struct net *net); 1088 int udplite6_proc_init(void); 1089 void udplite6_proc_exit(void); 1090 int ipv6_misc_proc_init(void); 1091 void ipv6_misc_proc_exit(void); 1092 int snmp6_register_dev(struct inet6_dev *idev); 1093 int snmp6_unregister_dev(struct inet6_dev *idev); 1094 1095 #else 1096 static inline int ac6_proc_init(struct net *net) { return 0; } 1097 static inline void ac6_proc_exit(struct net *net) { } 1098 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; } 1099 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; } 1100 #endif 1101 1102 #ifdef CONFIG_SYSCTL 1103 extern struct ctl_table ipv6_route_table_template[]; 1104 1105 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net); 1106 struct ctl_table *ipv6_route_sysctl_init(struct net *net); 1107 int ipv6_sysctl_register(void); 1108 void ipv6_sysctl_unregister(void); 1109 #endif 1110 1111 int ipv6_sock_mc_join(struct sock *sk, int ifindex, 1112 const struct in6_addr *addr); 1113 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, 1114 const struct in6_addr *addr); 1115 #endif /* _NET_IPV6_H */ 1116