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 __u16 gso_size; 302 }; 303 304 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np) 305 { 306 struct ipv6_txoptions *opt; 307 308 rcu_read_lock(); 309 opt = rcu_dereference(np->opt); 310 if (opt) { 311 if (!refcount_inc_not_zero(&opt->refcnt)) 312 opt = NULL; 313 else 314 opt = rcu_pointer_handoff(opt); 315 } 316 rcu_read_unlock(); 317 return opt; 318 } 319 320 static inline void txopt_put(struct ipv6_txoptions *opt) 321 { 322 if (opt && refcount_dec_and_test(&opt->refcnt)) 323 kfree_rcu(opt, rcu); 324 } 325 326 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label); 327 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 328 struct ip6_flowlabel *fl, 329 struct ipv6_txoptions *fopt); 330 void fl6_free_socklist(struct sock *sk); 331 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen); 332 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 333 int flags); 334 int ip6_flowlabel_init(void); 335 void ip6_flowlabel_cleanup(void); 336 bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np); 337 338 static inline void fl6_sock_release(struct ip6_flowlabel *fl) 339 { 340 if (fl) 341 atomic_dec(&fl->users); 342 } 343 344 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info); 345 346 void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, 347 struct icmp6hdr *thdr, int len); 348 349 int ip6_ra_control(struct sock *sk, int sel); 350 351 int ipv6_parse_hopopts(struct sk_buff *skb); 352 353 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk, 354 struct ipv6_txoptions *opt); 355 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk, 356 struct ipv6_txoptions *opt, 357 int newtype, 358 struct ipv6_opt_hdr __user *newopt, 359 int newoptlen); 360 struct ipv6_txoptions * 361 ipv6_renew_options_kern(struct sock *sk, 362 struct ipv6_txoptions *opt, 363 int newtype, 364 struct ipv6_opt_hdr *newopt, 365 int newoptlen); 366 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, 367 struct ipv6_txoptions *opt); 368 369 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb, 370 const struct inet6_skb_parm *opt); 371 struct ipv6_txoptions *ipv6_update_options(struct sock *sk, 372 struct ipv6_txoptions *opt); 373 374 static inline bool ipv6_accept_ra(struct inet6_dev *idev) 375 { 376 /* If forwarding is enabled, RA are not accepted unless the special 377 * hybrid mode (accept_ra=2) is enabled. 378 */ 379 return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 : 380 idev->cnf.accept_ra; 381 } 382 383 #define IPV6_FRAG_HIGH_THRESH (4 * 1024*1024) /* 4194304 */ 384 #define IPV6_FRAG_LOW_THRESH (3 * 1024*1024) /* 3145728 */ 385 #define IPV6_FRAG_TIMEOUT (60 * HZ) /* 60 seconds */ 386 387 int __ipv6_addr_type(const struct in6_addr *addr); 388 static inline int ipv6_addr_type(const struct in6_addr *addr) 389 { 390 return __ipv6_addr_type(addr) & 0xffff; 391 } 392 393 static inline int ipv6_addr_scope(const struct in6_addr *addr) 394 { 395 return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK; 396 } 397 398 static inline int __ipv6_addr_src_scope(int type) 399 { 400 return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16); 401 } 402 403 static inline int ipv6_addr_src_scope(const struct in6_addr *addr) 404 { 405 return __ipv6_addr_src_scope(__ipv6_addr_type(addr)); 406 } 407 408 static inline bool __ipv6_addr_needs_scope_id(int type) 409 { 410 return type & IPV6_ADDR_LINKLOCAL || 411 (type & IPV6_ADDR_MULTICAST && 412 (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL))); 413 } 414 415 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface) 416 { 417 return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0; 418 } 419 420 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2) 421 { 422 return memcmp(a1, a2, sizeof(struct in6_addr)); 423 } 424 425 static inline bool 426 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m, 427 const struct in6_addr *a2) 428 { 429 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 430 const unsigned long *ul1 = (const unsigned long *)a1; 431 const unsigned long *ulm = (const unsigned long *)m; 432 const unsigned long *ul2 = (const unsigned long *)a2; 433 434 return !!(((ul1[0] ^ ul2[0]) & ulm[0]) | 435 ((ul1[1] ^ ul2[1]) & ulm[1])); 436 #else 437 return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) | 438 ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) | 439 ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) | 440 ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3])); 441 #endif 442 } 443 444 static inline void ipv6_addr_prefix(struct in6_addr *pfx, 445 const struct in6_addr *addr, 446 int plen) 447 { 448 /* caller must guarantee 0 <= plen <= 128 */ 449 int o = plen >> 3, 450 b = plen & 0x7; 451 452 memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr)); 453 memcpy(pfx->s6_addr, addr, o); 454 if (b != 0) 455 pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b); 456 } 457 458 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr, 459 const struct in6_addr *pfx, 460 int plen) 461 { 462 /* caller must guarantee 0 <= plen <= 128 */ 463 int o = plen >> 3, 464 b = plen & 0x7; 465 466 memcpy(addr->s6_addr, pfx, o); 467 if (b != 0) { 468 addr->s6_addr[o] &= ~(0xff00 >> b); 469 addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b)); 470 } 471 } 472 473 static inline void __ipv6_addr_set_half(__be32 *addr, 474 __be32 wh, __be32 wl) 475 { 476 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 477 #if defined(__BIG_ENDIAN) 478 if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) { 479 *(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl)); 480 return; 481 } 482 #elif defined(__LITTLE_ENDIAN) 483 if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) { 484 *(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh)); 485 return; 486 } 487 #endif 488 #endif 489 addr[0] = wh; 490 addr[1] = wl; 491 } 492 493 static inline void ipv6_addr_set(struct in6_addr *addr, 494 __be32 w1, __be32 w2, 495 __be32 w3, __be32 w4) 496 { 497 __ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2); 498 __ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4); 499 } 500 501 static inline bool ipv6_addr_equal(const struct in6_addr *a1, 502 const struct in6_addr *a2) 503 { 504 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 505 const unsigned long *ul1 = (const unsigned long *)a1; 506 const unsigned long *ul2 = (const unsigned long *)a2; 507 508 return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL; 509 #else 510 return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) | 511 (a1->s6_addr32[1] ^ a2->s6_addr32[1]) | 512 (a1->s6_addr32[2] ^ a2->s6_addr32[2]) | 513 (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0; 514 #endif 515 } 516 517 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 518 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1, 519 const __be64 *a2, 520 unsigned int len) 521 { 522 if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len)))) 523 return false; 524 return true; 525 } 526 527 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1, 528 const struct in6_addr *addr2, 529 unsigned int prefixlen) 530 { 531 const __be64 *a1 = (const __be64 *)addr1; 532 const __be64 *a2 = (const __be64 *)addr2; 533 534 if (prefixlen >= 64) { 535 if (a1[0] ^ a2[0]) 536 return false; 537 return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64); 538 } 539 return __ipv6_prefix_equal64_half(a1, a2, prefixlen); 540 } 541 #else 542 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1, 543 const struct in6_addr *addr2, 544 unsigned int prefixlen) 545 { 546 const __be32 *a1 = addr1->s6_addr32; 547 const __be32 *a2 = addr2->s6_addr32; 548 unsigned int pdw, pbi; 549 550 /* check complete u32 in prefix */ 551 pdw = prefixlen >> 5; 552 if (pdw && memcmp(a1, a2, pdw << 2)) 553 return false; 554 555 /* check incomplete u32 in prefix */ 556 pbi = prefixlen & 0x1f; 557 if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi)))) 558 return false; 559 560 return true; 561 } 562 #endif 563 564 struct inet_frag_queue; 565 566 enum ip6_defrag_users { 567 IP6_DEFRAG_LOCAL_DELIVER, 568 IP6_DEFRAG_CONNTRACK_IN, 569 __IP6_DEFRAG_CONNTRACK_IN = IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX, 570 IP6_DEFRAG_CONNTRACK_OUT, 571 __IP6_DEFRAG_CONNTRACK_OUT = IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX, 572 IP6_DEFRAG_CONNTRACK_BRIDGE_IN, 573 __IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX, 574 }; 575 576 void ip6_frag_init(struct inet_frag_queue *q, const void *a); 577 extern const struct rhashtable_params ip6_rhash_params; 578 579 /* 580 * Equivalent of ipv4 struct ip 581 */ 582 struct frag_queue { 583 struct inet_frag_queue q; 584 585 int iif; 586 __u16 nhoffset; 587 u8 ecn; 588 }; 589 590 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq); 591 592 static inline bool ipv6_addr_any(const struct in6_addr *a) 593 { 594 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 595 const unsigned long *ul = (const unsigned long *)a; 596 597 return (ul[0] | ul[1]) == 0UL; 598 #else 599 return (a->s6_addr32[0] | a->s6_addr32[1] | 600 a->s6_addr32[2] | a->s6_addr32[3]) == 0; 601 #endif 602 } 603 604 static inline u32 ipv6_addr_hash(const struct in6_addr *a) 605 { 606 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 607 const unsigned long *ul = (const unsigned long *)a; 608 unsigned long x = ul[0] ^ ul[1]; 609 610 return (u32)(x ^ (x >> 32)); 611 #else 612 return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^ 613 a->s6_addr32[2] ^ a->s6_addr32[3]); 614 #endif 615 } 616 617 /* more secured version of ipv6_addr_hash() */ 618 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval) 619 { 620 u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1]; 621 622 return jhash_3words(v, 623 (__force u32)a->s6_addr32[2], 624 (__force u32)a->s6_addr32[3], 625 initval); 626 } 627 628 static inline bool ipv6_addr_loopback(const struct in6_addr *a) 629 { 630 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 631 const __be64 *be = (const __be64 *)a; 632 633 return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL; 634 #else 635 return (a->s6_addr32[0] | a->s6_addr32[1] | 636 a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0; 637 #endif 638 } 639 640 /* 641 * Note that we must __force cast these to unsigned long to make sparse happy, 642 * since all of the endian-annotated types are fixed size regardless of arch. 643 */ 644 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a) 645 { 646 return ( 647 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 648 *(unsigned long *)a | 649 #else 650 (__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) | 651 #endif 652 (__force unsigned long)(a->s6_addr32[2] ^ 653 cpu_to_be32(0x0000ffff))) == 0UL; 654 } 655 656 static inline u32 ipv6_portaddr_hash(const struct net *net, 657 const struct in6_addr *addr6, 658 unsigned int port) 659 { 660 unsigned int hash, mix = net_hash_mix(net); 661 662 if (ipv6_addr_any(addr6)) 663 hash = jhash_1word(0, mix); 664 else if (ipv6_addr_v4mapped(addr6)) 665 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix); 666 else 667 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix); 668 669 return hash ^ port; 670 } 671 672 /* 673 * Check for a RFC 4843 ORCHID address 674 * (Overlay Routable Cryptographic Hash Identifiers) 675 */ 676 static inline bool ipv6_addr_orchid(const struct in6_addr *a) 677 { 678 return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010); 679 } 680 681 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr) 682 { 683 return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000); 684 } 685 686 static inline void ipv6_addr_set_v4mapped(const __be32 addr, 687 struct in6_addr *v4mapped) 688 { 689 ipv6_addr_set(v4mapped, 690 0, 0, 691 htonl(0x0000FFFF), 692 addr); 693 } 694 695 /* 696 * find the first different bit between two addresses 697 * length of address must be a multiple of 32bits 698 */ 699 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen) 700 { 701 const __be32 *a1 = token1, *a2 = token2; 702 int i; 703 704 addrlen >>= 2; 705 706 for (i = 0; i < addrlen; i++) { 707 __be32 xb = a1[i] ^ a2[i]; 708 if (xb) 709 return i * 32 + 31 - __fls(ntohl(xb)); 710 } 711 712 /* 713 * we should *never* get to this point since that 714 * would mean the addrs are equal 715 * 716 * However, we do get to it 8) And exacly, when 717 * addresses are equal 8) 718 * 719 * ip route add 1111::/128 via ... 720 * ip route add 1111::/64 via ... 721 * and we are here. 722 * 723 * Ideally, this function should stop comparison 724 * at prefix length. It does not, but it is still OK, 725 * if returned value is greater than prefix length. 726 * --ANK (980803) 727 */ 728 return addrlen << 5; 729 } 730 731 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 732 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen) 733 { 734 const __be64 *a1 = token1, *a2 = token2; 735 int i; 736 737 addrlen >>= 3; 738 739 for (i = 0; i < addrlen; i++) { 740 __be64 xb = a1[i] ^ a2[i]; 741 if (xb) 742 return i * 64 + 63 - __fls(be64_to_cpu(xb)); 743 } 744 745 return addrlen << 6; 746 } 747 #endif 748 749 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen) 750 { 751 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 752 if (__builtin_constant_p(addrlen) && !(addrlen & 7)) 753 return __ipv6_addr_diff64(token1, token2, addrlen); 754 #endif 755 return __ipv6_addr_diff32(token1, token2, addrlen); 756 } 757 758 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2) 759 { 760 return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr)); 761 } 762 763 __be32 ipv6_select_ident(struct net *net, 764 const struct in6_addr *daddr, 765 const struct in6_addr *saddr); 766 __be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb); 767 768 int ip6_dst_hoplimit(struct dst_entry *dst); 769 770 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6, 771 struct dst_entry *dst) 772 { 773 int hlimit; 774 775 if (ipv6_addr_is_multicast(&fl6->daddr)) 776 hlimit = np->mcast_hops; 777 else 778 hlimit = np->hop_limit; 779 if (hlimit < 0) 780 hlimit = ip6_dst_hoplimit(dst); 781 return hlimit; 782 } 783 784 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store 785 * Equivalent to : flow->v6addrs.src = iph->saddr; 786 * flow->v6addrs.dst = iph->daddr; 787 */ 788 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow, 789 const struct ipv6hdr *iph) 790 { 791 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) != 792 offsetof(typeof(flow->addrs), v6addrs.src) + 793 sizeof(flow->addrs.v6addrs.src)); 794 memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs)); 795 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; 796 } 797 798 #if IS_ENABLED(CONFIG_IPV6) 799 800 /* Sysctl settings for net ipv6.auto_flowlabels */ 801 #define IP6_AUTO_FLOW_LABEL_OFF 0 802 #define IP6_AUTO_FLOW_LABEL_OPTOUT 1 803 #define IP6_AUTO_FLOW_LABEL_OPTIN 2 804 #define IP6_AUTO_FLOW_LABEL_FORCED 3 805 806 #define IP6_AUTO_FLOW_LABEL_MAX IP6_AUTO_FLOW_LABEL_FORCED 807 808 #define IP6_DEFAULT_AUTO_FLOW_LABELS IP6_AUTO_FLOW_LABEL_OPTOUT 809 810 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, 811 __be32 flowlabel, bool autolabel, 812 struct flowi6 *fl6) 813 { 814 u32 hash; 815 816 /* @flowlabel may include more than a flow label, eg, the traffic class. 817 * Here we want only the flow label value. 818 */ 819 flowlabel &= IPV6_FLOWLABEL_MASK; 820 821 if (flowlabel || 822 net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF || 823 (!autolabel && 824 net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED)) 825 return flowlabel; 826 827 hash = skb_get_hash_flowi6(skb, fl6); 828 829 /* Since this is being sent on the wire obfuscate hash a bit 830 * to minimize possbility that any useful information to an 831 * attacker is leaked. Only lower 20 bits are relevant. 832 */ 833 rol32(hash, 16); 834 835 flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK; 836 837 if (net->ipv6.sysctl.flowlabel_state_ranges) 838 flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG; 839 840 return flowlabel; 841 } 842 843 static inline int ip6_default_np_autolabel(struct net *net) 844 { 845 switch (net->ipv6.sysctl.auto_flowlabels) { 846 case IP6_AUTO_FLOW_LABEL_OFF: 847 case IP6_AUTO_FLOW_LABEL_OPTIN: 848 default: 849 return 0; 850 case IP6_AUTO_FLOW_LABEL_OPTOUT: 851 case IP6_AUTO_FLOW_LABEL_FORCED: 852 return 1; 853 } 854 } 855 #else 856 static inline void ip6_set_txhash(struct sock *sk) { } 857 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, 858 __be32 flowlabel, bool autolabel, 859 struct flowi6 *fl6) 860 { 861 return flowlabel; 862 } 863 static inline int ip6_default_np_autolabel(struct net *net) 864 { 865 return 0; 866 } 867 #endif 868 869 #if IS_ENABLED(CONFIG_IPV6) 870 static inline int ip6_multipath_hash_policy(const struct net *net) 871 { 872 return net->ipv6.sysctl.multipath_hash_policy; 873 } 874 #else 875 static inline int ip6_multipath_hash_policy(const struct net *net) 876 { 877 return 0; 878 } 879 #endif 880 881 /* 882 * Header manipulation 883 */ 884 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass, 885 __be32 flowlabel) 886 { 887 *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel; 888 } 889 890 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr) 891 { 892 return *(__be32 *)hdr & IPV6_FLOWINFO_MASK; 893 } 894 895 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr) 896 { 897 return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK; 898 } 899 900 static inline u8 ip6_tclass(__be32 flowinfo) 901 { 902 return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT; 903 } 904 905 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel) 906 { 907 return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel; 908 } 909 910 static inline __be32 flowi6_get_flowlabel(const struct flowi6 *fl6) 911 { 912 return fl6->flowlabel & IPV6_FLOWLABEL_MASK; 913 } 914 915 /* 916 * Prototypes exported by ipv6 917 */ 918 919 /* 920 * rcv function (called from netdevice level) 921 */ 922 923 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, 924 struct packet_type *pt, struct net_device *orig_dev); 925 926 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb); 927 928 /* 929 * upper-layer output functions 930 */ 931 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, 932 __u32 mark, struct ipv6_txoptions *opt, int tclass); 933 934 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr); 935 936 int ip6_append_data(struct sock *sk, 937 int getfrag(void *from, char *to, int offset, int len, 938 int odd, struct sk_buff *skb), 939 void *from, int length, int transhdrlen, 940 struct ipcm6_cookie *ipc6, struct flowi6 *fl6, 941 struct rt6_info *rt, unsigned int flags, 942 const struct sockcm_cookie *sockc); 943 944 int ip6_push_pending_frames(struct sock *sk); 945 946 void ip6_flush_pending_frames(struct sock *sk); 947 948 int ip6_send_skb(struct sk_buff *skb); 949 950 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue, 951 struct inet_cork_full *cork, 952 struct inet6_cork *v6_cork); 953 struct sk_buff *ip6_make_skb(struct sock *sk, 954 int getfrag(void *from, char *to, int offset, 955 int len, int odd, struct sk_buff *skb), 956 void *from, int length, int transhdrlen, 957 struct ipcm6_cookie *ipc6, struct flowi6 *fl6, 958 struct rt6_info *rt, unsigned int flags, 959 struct inet_cork_full *cork, 960 const struct sockcm_cookie *sockc); 961 962 static inline struct sk_buff *ip6_finish_skb(struct sock *sk) 963 { 964 return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork, 965 &inet6_sk(sk)->cork); 966 } 967 968 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst, 969 struct flowi6 *fl6); 970 struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6, 971 const struct in6_addr *final_dst); 972 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6, 973 const struct in6_addr *final_dst, 974 bool connected); 975 struct dst_entry *ip6_blackhole_route(struct net *net, 976 struct dst_entry *orig_dst); 977 978 /* 979 * skb processing functions 980 */ 981 982 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb); 983 int ip6_forward(struct sk_buff *skb); 984 int ip6_input(struct sk_buff *skb); 985 int ip6_mc_input(struct sk_buff *skb); 986 987 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 988 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 989 990 /* 991 * Extension header (options) processing 992 */ 993 994 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, 995 u8 *proto, struct in6_addr **daddr_p, 996 struct in6_addr *saddr); 997 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, 998 u8 *proto); 999 1000 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp, 1001 __be16 *frag_offp); 1002 1003 bool ipv6_ext_hdr(u8 nexthdr); 1004 1005 enum { 1006 IP6_FH_F_FRAG = (1 << 0), 1007 IP6_FH_F_AUTH = (1 << 1), 1008 IP6_FH_F_SKIP_RH = (1 << 2), 1009 }; 1010 1011 /* find specified header and get offset to it */ 1012 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target, 1013 unsigned short *fragoff, int *fragflg); 1014 1015 int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type); 1016 1017 struct in6_addr *fl6_update_dst(struct flowi6 *fl6, 1018 const struct ipv6_txoptions *opt, 1019 struct in6_addr *orig); 1020 1021 /* 1022 * socket options (ipv6_sockglue.c) 1023 */ 1024 1025 int ipv6_setsockopt(struct sock *sk, int level, int optname, 1026 char __user *optval, unsigned int optlen); 1027 int ipv6_getsockopt(struct sock *sk, int level, int optname, 1028 char __user *optval, int __user *optlen); 1029 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname, 1030 char __user *optval, unsigned int optlen); 1031 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname, 1032 char __user *optval, int __user *optlen); 1033 1034 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, 1035 int addr_len); 1036 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len); 1037 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr, 1038 int addr_len); 1039 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr); 1040 void ip6_datagram_release_cb(struct sock *sk); 1041 1042 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, 1043 int *addr_len); 1044 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len, 1045 int *addr_len); 1046 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 1047 u32 info, u8 *payload); 1048 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info); 1049 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu); 1050 1051 int inet6_release(struct socket *sock); 1052 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len); 1053 int inet6_getname(struct socket *sock, struct sockaddr *uaddr, 1054 int peer); 1055 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg); 1056 1057 int inet6_hash_connect(struct inet_timewait_death_row *death_row, 1058 struct sock *sk); 1059 1060 /* 1061 * reassembly.c 1062 */ 1063 extern const struct proto_ops inet6_stream_ops; 1064 extern const struct proto_ops inet6_dgram_ops; 1065 extern const struct proto_ops inet6_sockraw_ops; 1066 1067 struct group_source_req; 1068 struct group_filter; 1069 1070 int ip6_mc_source(int add, int omode, struct sock *sk, 1071 struct group_source_req *pgsr); 1072 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf); 1073 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, 1074 struct group_filter __user *optval, int __user *optlen); 1075 1076 #ifdef CONFIG_PROC_FS 1077 int ac6_proc_init(struct net *net); 1078 void ac6_proc_exit(struct net *net); 1079 int raw6_proc_init(void); 1080 void raw6_proc_exit(void); 1081 int tcp6_proc_init(struct net *net); 1082 void tcp6_proc_exit(struct net *net); 1083 int udp6_proc_init(struct net *net); 1084 void udp6_proc_exit(struct net *net); 1085 int udplite6_proc_init(void); 1086 void udplite6_proc_exit(void); 1087 int ipv6_misc_proc_init(void); 1088 void ipv6_misc_proc_exit(void); 1089 int snmp6_register_dev(struct inet6_dev *idev); 1090 int snmp6_unregister_dev(struct inet6_dev *idev); 1091 1092 #else 1093 static inline int ac6_proc_init(struct net *net) { return 0; } 1094 static inline void ac6_proc_exit(struct net *net) { } 1095 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; } 1096 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; } 1097 #endif 1098 1099 #ifdef CONFIG_SYSCTL 1100 extern struct ctl_table ipv6_route_table_template[]; 1101 1102 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net); 1103 struct ctl_table *ipv6_route_sysctl_init(struct net *net); 1104 int ipv6_sysctl_register(void); 1105 void ipv6_sysctl_unregister(void); 1106 #endif 1107 1108 int ipv6_sock_mc_join(struct sock *sk, int ifindex, 1109 const struct in6_addr *addr); 1110 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, 1111 const struct in6_addr *addr); 1112 #endif /* _NET_IPV6_H */ 1113