include/net/ipv6.h

   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 <net/if_inet6.h>
  20 #include <net/ndisc.h>
  21 #include <net/flow.h>
  22 #include <net/snmp.h>
  23
  24 #define SIN6_LEN_RFC2133        24
  25
  26 #define IPV6_MAXPLEN            65535
  27
  28 /*
  29  *      NextHeader field of IPv6 header
  30  */
  31
  32 #define NEXTHDR_HOP             0       /* Hop-by-hop option header. */
  33 #define NEXTHDR_TCP             6       /* TCP segment. */
  34 #define NEXTHDR_UDP             17      /* UDP message. */
  35 #define NEXTHDR_IPV6            41      /* IPv6 in IPv6 */
  36 #define NEXTHDR_ROUTING         43      /* Routing header. */
  37 #define NEXTHDR_FRAGMENT        44      /* Fragmentation/reassembly header. */
  38 #define NEXTHDR_GRE             47      /* GRE header. */
  39 #define NEXTHDR_ESP             50      /* Encapsulating security payload. */
  40 #define NEXTHDR_AUTH            51      /* Authentication header. */
  41 #define NEXTHDR_ICMP            58      /* ICMP for IPv6. */
  42 #define NEXTHDR_NONE            59      /* No next header */
  43 #define NEXTHDR_DEST            60      /* Destination options header. */
  44 #define NEXTHDR_SCTP            132     /* SCTP message. */
  45 #define NEXTHDR_MOBILITY        135     /* Mobility header. */
  46
  47 #define NEXTHDR_MAX             255
  48
  49
  50
  51 #define IPV6_DEFAULT_HOPLIMIT   64
  52 #define IPV6_DEFAULT_MCASTHOPS  1
  53
  54 /*
  55  *      Addr type
  56  *
  57  *      type    -       unicast | multicast
  58  *      scope   -       local   | site      | global
  59  *      v4      -       compat
  60  *      v4mapped
  61  *      any
  62  *      loopback
  63  */
  64
  65 #define IPV6_ADDR_ANY           0x0000U
  66
  67 #define IPV6_ADDR_UNICAST       0x0001U
  68 #define IPV6_ADDR_MULTICAST     0x0002U
  69
  70 #define IPV6_ADDR_LOOPBACK      0x0010U
  71 #define IPV6_ADDR_LINKLOCAL     0x0020U
  72 #define IPV6_ADDR_SITELOCAL     0x0040U
  73
  74 #define IPV6_ADDR_COMPATv4      0x0080U
  75
  76 #define IPV6_ADDR_SCOPE_MASK    0x00f0U
  77
  78 #define IPV6_ADDR_MAPPED        0x1000U
  79
  80 /*
  81  *      Addr scopes
  82  */
  83 #define IPV6_ADDR_MC_SCOPE(a)   \
  84         ((a)->s6_addr[1] & 0x0f)        /* nonstandard */
  85 #define __IPV6_ADDR_SCOPE_INVALID       -1
  86 #define IPV6_ADDR_SCOPE_NODELOCAL       0x01
  87 #define IPV6_ADDR_SCOPE_LINKLOCAL       0x02
  88 #define IPV6_ADDR_SCOPE_SITELOCAL       0x05
  89 #define IPV6_ADDR_SCOPE_ORGLOCAL        0x08
  90 #define IPV6_ADDR_SCOPE_GLOBAL          0x0e
  91
  92 /*
  93  *      Addr flags
  94  */
  95 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a)  \
  96         ((a)->s6_addr[1] & 0x10)
  97 #define IPV6_ADDR_MC_FLAG_PREFIX(a)     \
  98         ((a)->s6_addr[1] & 0x20)
  99 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a) \
 100         ((a)->s6_addr[1] & 0x40)
 101
 102 /*
 103  *      fragmentation header
 104  */
 105
 106 struct frag_hdr {
 107         __u8    nexthdr;
 108         __u8    reserved;
 109         __be16  frag_off;
 110         __be32  identification;
 111 };
 112
 113 #define IP6_MF  0x0001
 114
 115 #include <net/sock.h>
 116
 117 /* sysctls */
 118 extern int sysctl_mld_max_msf;
 119
 120 #define _DEVINC(net, statname, modifier, idev, field)                   \
 121 ({                                                                      \
 122         struct inet6_dev *_idev = (idev);                               \
 123         if (likely(_idev != NULL))                                      \
 124                 SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \
 125         SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
 126 })
 127
 128 /* per device counters are atomic_long_t */
 129 #define _DEVINCATOMIC(net, statname, modifier, idev, field)             \
 130 ({                                                                      \
 131         struct inet6_dev *_idev = (idev);                               \
 132         if (likely(_idev != NULL))                                      \
 133                 SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 134         SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
 135 })
 136
 137 /* per device and per net counters are atomic_long_t */
 138 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)               \
 139 ({                                                                      \
 140         struct inet6_dev *_idev = (idev);                               \
 141         if (likely(_idev != NULL))                                      \
 142                 SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 143         SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
 144 })
 145
 146 #define _DEVADD(net, statname, modifier, idev, field, val)              \
 147 ({                                                                      \
 148         struct inet6_dev *_idev = (idev);                               \
 149         if (likely(_idev != NULL))                                      \
 150                 SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \
 151         SNMP_ADD_STATS##modifier((net)->mib.statname##_statistics, (field), (val));\
 152 })
 153
 154 #define _DEVUPD(net, statname, modifier, idev, field, val)              \
 155 ({                                                                      \
 156         struct inet6_dev *_idev = (idev);                               \
 157         if (likely(_idev != NULL))                                      \
 158                 SNMP_UPD_PO_STATS##modifier((_idev)->stats.statname, field, (val)); \
 159         SNMP_UPD_PO_STATS##modifier((net)->mib.statname##_statistics, field, (val));\
 160 })
 161
 162 /* MIBs */
 163
 164 #define IP6_INC_STATS(net, idev,field)          \
 165                 _DEVINC(net, ipv6, 64, idev, field)
 166 #define IP6_INC_STATS_BH(net, idev,field)       \
 167                 _DEVINC(net, ipv6, 64_BH, idev, field)
 168 #define IP6_ADD_STATS(net, idev,field,val)      \
 169                 _DEVADD(net, ipv6, 64, idev, field, val)
 170 #define IP6_ADD_STATS_BH(net, idev,field,val)   \
 171                 _DEVADD(net, ipv6, 64_BH, idev, field, val)
 172 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
 173                 _DEVUPD(net, ipv6, 64, idev, field, val)
 174 #define IP6_UPD_PO_STATS_BH(net, idev,field,val)   \
 175                 _DEVUPD(net, ipv6, 64_BH, idev, field, val)
 176 #define ICMP6_INC_STATS(net, idev, field)       \
 177                 _DEVINCATOMIC(net, icmpv6, , idev, field)
 178 #define ICMP6_INC_STATS_BH(net, idev, field)    \
 179                 _DEVINCATOMIC(net, icmpv6, _BH, idev, field)
 180
 181 #define ICMP6MSGOUT_INC_STATS(net, idev, field)         \
 182         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 183 #define ICMP6MSGOUT_INC_STATS_BH(net, idev, field)      \
 184         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 185 #define ICMP6MSGIN_INC_STATS_BH(net, idev, field)       \
 186         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
 187
 188 struct ip6_ra_chain {
 189         struct ip6_ra_chain     *next;
 190         struct sock             *sk;
 191         int                     sel;
 192         void                    (*destructor)(struct sock *);
 193 };
 194
 195 extern struct ip6_ra_chain      *ip6_ra_chain;
 196 extern rwlock_t ip6_ra_lock;
 197
 198 /*
 199    This structure is prepared by protocol, when parsing
 200    ancillary data and passed to IPv6.
 201  */
 202
 203 struct ipv6_txoptions {
 204         /* Length of this structure */
 205         int                     tot_len;
 206
 207         /* length of extension headers   */
 208
 209         __u16                   opt_flen;       /* after fragment hdr */
 210         __u16                   opt_nflen;      /* before fragment hdr */
 211
 212         struct ipv6_opt_hdr     *hopopt;
 213         struct ipv6_opt_hdr     *dst0opt;
 214         struct ipv6_rt_hdr      *srcrt; /* Routing Header */
 215         struct ipv6_opt_hdr     *dst1opt;
 216
 217         /* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
 218 };
 219
 220 struct ip6_flowlabel {
 221         struct ip6_flowlabel __rcu *next;
 222         __be32                  label;
 223         atomic_t                users;
 224         struct in6_addr         dst;
 225         struct ipv6_txoptions   *opt;
 226         unsigned long           linger;
 227         struct rcu_head         rcu;
 228         u8                      share;
 229         union {
 230                 struct pid *pid;
 231                 kuid_t uid;
 232         } owner;
 233         unsigned long           lastuse;
 234         unsigned long           expires;
 235         struct net              *fl_net;
 236 };
 237
 238 #define IPV6_FLOWINFO_MASK      cpu_to_be32(0x0FFFFFFF)
 239 #define IPV6_FLOWLABEL_MASK     cpu_to_be32(0x000FFFFF)
 240
 241 struct ipv6_fl_socklist {
 242         struct ipv6_fl_socklist __rcu   *next;
 243         struct ip6_flowlabel            *fl;
 244         struct rcu_head                 rcu;
 245 };
 246
 247 extern struct ip6_flowlabel     *fl6_sock_lookup(struct sock *sk, __be32 label);
 248 extern struct ipv6_txoptions    *fl6_merge_options(struct ipv6_txoptions * opt_space,
 249                                                    struct ip6_flowlabel * fl,
 250                                                    struct ipv6_txoptions * fopt);
 251 extern void                     fl6_free_socklist(struct sock *sk);
 252 extern int                      ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
 253 extern int                      ip6_flowlabel_init(void);
 254 extern void                     ip6_flowlabel_cleanup(void);
 255
 256 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
 257 {
 258         if (fl)
 259                 atomic_dec(&fl->users);
 260 }
 261
 262 extern void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
 263
 264 int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
 265                                struct icmp6hdr *thdr, int len);
 266
 267 struct dst_entry *icmpv6_route_lookup(struct net *net, struct sk_buff *skb,
 268                                       struct sock *sk, struct flowi6 *fl6);
 269
 270 extern int                      ip6_ra_control(struct sock *sk, int sel);
 271
 272 extern int                      ipv6_parse_hopopts(struct sk_buff *skb);
 273
 274 extern struct ipv6_txoptions *  ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt);
 275 extern struct ipv6_txoptions *  ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
 276                                                    int newtype,
 277                                                    struct ipv6_opt_hdr __user *newopt,
 278                                                    int newoptlen);
 279 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
 280                                           struct ipv6_txoptions *opt);
 281
 282 extern bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb);
 283
 284 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 285 {
 286         /* If forwarding is enabled, RA are not accepted unless the special
 287          * hybrid mode (accept_ra=2) is enabled.
 288          */
 289         return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
 290             idev->cnf.accept_ra;
 291 }
 292
 293 #if IS_ENABLED(CONFIG_IPV6)
 294 static inline int ip6_frag_nqueues(struct net *net)
 295 {
 296         return net->ipv6.frags.nqueues;
 297 }
 298
 299 static inline int ip6_frag_mem(struct net *net)
 300 {
 301         return sum_frag_mem_limit(&net->ipv6.frags);
 302 }
 303 #endif
 304
 305 #define IPV6_FRAG_HIGH_THRESH   (4 * 1024*1024) /* 4194304 */
 306 #define IPV6_FRAG_LOW_THRESH    (3 * 1024*1024) /* 3145728 */
 307 #define IPV6_FRAG_TIMEOUT       (60 * HZ)       /* 60 seconds */
 308
 309 extern int __ipv6_addr_type(const struct in6_addr *addr);
 310 static inline int ipv6_addr_type(const struct in6_addr *addr)
 311 {
 312         return __ipv6_addr_type(addr) & 0xffff;
 313 }
 314
 315 static inline int ipv6_addr_scope(const struct in6_addr *addr)
 316 {
 317         return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
 318 }
 319
 320 static inline int __ipv6_addr_src_scope(int type)
 321 {
 322         return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
 323 }
 324
 325 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
 326 {
 327         return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
 328 }
 329
 330 static inline bool __ipv6_addr_needs_scope_id(int type)
 331 {
 332         return type & IPV6_ADDR_LINKLOCAL ||
 333                (type & IPV6_ADDR_MULTICAST &&
 334                 (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
 335 }
 336
 337 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
 338 {
 339         return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
 340 }
 341
 342 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
 343 {
 344         return memcmp(a1, a2, sizeof(struct in6_addr));
 345 }
 346
 347 static inline bool
 348 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
 349                      const struct in6_addr *a2)
 350 {
 351 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 352         const unsigned long *ul1 = (const unsigned long *)a1;
 353         const unsigned long *ulm = (const unsigned long *)m;
 354         const unsigned long *ul2 = (const unsigned long *)a2;
 355
 356         return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
 357                   ((ul1[1] ^ ul2[1]) & ulm[1]));
 358 #else
 359         return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
 360                   ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
 361                   ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
 362                   ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
 363 #endif
 364 }
 365
 366 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
 367                                     const struct in6_addr *addr,
 368                                     int plen)
 369 {
 370         /* caller must guarantee 0 <= plen <= 128 */
 371         int o = plen >> 3,
 372             b = plen & 0x7;
 373
 374         memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
 375         memcpy(pfx->s6_addr, addr, o);
 376         if (b != 0)
 377                 pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
 378 }
 379
 380 static inline void __ipv6_addr_set_half(__be32 *addr,
 381                                         __be32 wh, __be32 wl)
 382 {
 383 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 384 #if defined(__BIG_ENDIAN)
 385         if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
 386                 *(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
 387                 return;
 388         }
 389 #elif defined(__LITTLE_ENDIAN)
 390         if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
 391                 *(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
 392                 return;
 393         }
 394 #endif
 395 #endif
 396         addr[0] = wh;
 397         addr[1] = wl;
 398 }
 399
 400 static inline void ipv6_addr_set(struct in6_addr *addr,
 401                                      __be32 w1, __be32 w2,
 402                                      __be32 w3, __be32 w4)
 403 {
 404         __ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
 405         __ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
 406 }
 407
 408 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
 409                                    const struct in6_addr *a2)
 410 {
 411 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 412         const unsigned long *ul1 = (const unsigned long *)a1;
 413         const unsigned long *ul2 = (const unsigned long *)a2;
 414
 415         return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
 416 #else
 417         return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
 418                 (a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
 419                 (a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
 420                 (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
 421 #endif
 422 }
 423
 424 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 425 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
 426                                               const __be64 *a2,
 427                                               unsigned int len)
 428 {
 429         if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
 430                 return false;
 431         return true;
 432 }
 433
 434 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 435                                      const struct in6_addr *addr2,
 436                                      unsigned int prefixlen)
 437 {
 438         const __be64 *a1 = (const __be64 *)addr1;
 439         const __be64 *a2 = (const __be64 *)addr2;
 440
 441         if (prefixlen >= 64) {
 442                 if (a1[0] ^ a2[0])
 443                         return false;
 444                 return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
 445         }
 446         return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
 447 }
 448 #else
 449 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 450                                      const struct in6_addr *addr2,
 451                                      unsigned int prefixlen)
 452 {
 453         const __be32 *a1 = addr1->s6_addr32;
 454         const __be32 *a2 = addr2->s6_addr32;
 455         unsigned int pdw, pbi;
 456
 457         /* check complete u32 in prefix */
 458         pdw = prefixlen >> 5;
 459         if (pdw && memcmp(a1, a2, pdw << 2))
 460                 return false;
 461
 462         /* check incomplete u32 in prefix */
 463         pbi = prefixlen & 0x1f;
 464         if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
 465                 return false;
 466
 467         return true;
 468 }
 469 #endif
 470
 471 struct inet_frag_queue;
 472
 473 enum ip6_defrag_users {
 474         IP6_DEFRAG_LOCAL_DELIVER,
 475         IP6_DEFRAG_CONNTRACK_IN,
 476         __IP6_DEFRAG_CONNTRACK_IN       = IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
 477         IP6_DEFRAG_CONNTRACK_OUT,
 478         __IP6_DEFRAG_CONNTRACK_OUT      = IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
 479         IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
 480         __IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
 481 };
 482
 483 struct ip6_create_arg {
 484         __be32 id;
 485         u32 user;
 486         const struct in6_addr *src;
 487         const struct in6_addr *dst;
 488         u8 ecn;
 489 };
 490
 491 void ip6_frag_init(struct inet_frag_queue *q, void *a);
 492 bool ip6_frag_match(struct inet_frag_queue *q, void *a);
 493
 494 /*
 495  *      Equivalent of ipv4 struct ip
 496  */
 497 struct frag_queue {
 498         struct inet_frag_queue  q;
 499
 500         __be32                  id;             /* fragment id          */
 501         u32                     user;
 502         struct in6_addr         saddr;
 503         struct in6_addr         daddr;
 504
 505         int                     iif;
 506         unsigned int            csum;
 507         __u16                   nhoffset;
 508         u8                      ecn;
 509 };
 510
 511 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
 512                            struct inet_frags *frags);
 513
 514 static inline bool ipv6_addr_any(const struct in6_addr *a)
 515 {
 516 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 517         const unsigned long *ul = (const unsigned long *)a;
 518
 519         return (ul[0] | ul[1]) == 0UL;
 520 #else
 521         return (a->s6_addr32[0] | a->s6_addr32[1] |
 522                 a->s6_addr32[2] | a->s6_addr32[3]) == 0;
 523 #endif
 524 }
 525
 526 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
 527 {
 528 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 529         const unsigned long *ul = (const unsigned long *)a;
 530         unsigned long x = ul[0] ^ ul[1];
 531
 532         return (u32)(x ^ (x >> 32));
 533 #else
 534         return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
 535                              a->s6_addr32[2] ^ a->s6_addr32[3]);
 536 #endif
 537 }
 538
 539 /* more secured version of ipv6_addr_hash() */
 540 static inline u32 ipv6_addr_jhash(const struct in6_addr *a)
 541 {
 542         u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
 543
 544         return jhash_3words(v,
 545                             (__force u32)a->s6_addr32[2],
 546                             (__force u32)a->s6_addr32[3],
 547                             ipv6_hash_secret);
 548 }
 549
 550 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
 551 {
 552 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 553         const unsigned long *ul = (const unsigned long *)a;
 554
 555         return (ul[0] | (ul[1] ^ cpu_to_be64(1))) == 0UL;
 556 #else
 557         return (a->s6_addr32[0] | a->s6_addr32[1] |
 558                 a->s6_addr32[2] | (a->s6_addr32[3] ^ htonl(1))) == 0;
 559 #endif
 560 }
 561
 562 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
 563 {
 564         return (
 565 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 566                 *(__be64 *)a |
 567 #else
 568                 (a->s6_addr32[0] | a->s6_addr32[1]) |
 569 #endif
 570                 (a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0UL;
 571 }
 572
 573 /*
 574  * Check for a RFC 4843 ORCHID address
 575  * (Overlay Routable Cryptographic Hash Identifiers)
 576  */
 577 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
 578 {
 579         return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
 580 }
 581
 582 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
 583                                           struct in6_addr *v4mapped)
 584 {
 585         ipv6_addr_set(v4mapped,
 586                         0, 0,
 587                         htonl(0x0000FFFF),
 588                         addr);
 589 }
 590
 591 /*
 592  * find the first different bit between two addresses
 593  * length of address must be a multiple of 32bits
 594  */
 595 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
 596 {
 597         const __be32 *a1 = token1, *a2 = token2;
 598         int i;
 599
 600         addrlen >>= 2;
 601
 602         for (i = 0; i < addrlen; i++) {
 603                 __be32 xb = a1[i] ^ a2[i];
 604                 if (xb)
 605                         return i * 32 + 31 - __fls(ntohl(xb));
 606         }
 607
 608         /*
 609          *      we should *never* get to this point since that
 610          *      would mean the addrs are equal
 611          *
 612          *      However, we do get to it 8) And exacly, when
 613          *      addresses are equal 8)
 614          *
 615          *      ip route add 1111::/128 via ...
 616          *      ip route add 1111::/64 via ...
 617          *      and we are here.
 618          *
 619          *      Ideally, this function should stop comparison
 620          *      at prefix length. It does not, but it is still OK,
 621          *      if returned value is greater than prefix length.
 622          *                                      --ANK (980803)
 623          */
 624         return addrlen << 5;
 625 }
 626
 627 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 628 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
 629 {
 630         const __be64 *a1 = token1, *a2 = token2;
 631         int i;
 632
 633         addrlen >>= 3;
 634
 635         for (i = 0; i < addrlen; i++) {
 636                 __be64 xb = a1[i] ^ a2[i];
 637                 if (xb)
 638                         return i * 64 + 63 - __fls(be64_to_cpu(xb));
 639         }
 640
 641         return addrlen << 6;
 642 }
 643 #endif
 644
 645 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
 646 {
 647 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 648         if (__builtin_constant_p(addrlen) && !(addrlen & 7))
 649                 return __ipv6_addr_diff64(token1, token2, addrlen);
 650 #endif
 651         return __ipv6_addr_diff32(token1, token2, addrlen);
 652 }
 653
 654 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
 655 {
 656         return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
 657 }
 658
 659 extern void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt);
 660
 661 extern int ip6_dst_hoplimit(struct dst_entry *dst);
 662
 663 /*
 664  *      Header manipulation
 665  */
 666 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
 667                                 __be32 flowlabel)
 668 {
 669         *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
 670 }
 671
 672 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
 673 {
 674         return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
 675 }
 676
 677 /*
 678  *      Prototypes exported by ipv6
 679  */
 680
 681 /*
 682  *      rcv function (called from netdevice level)
 683  */
 684
 685 extern int                      ipv6_rcv(struct sk_buff *skb,
 686                                          struct net_device *dev,
 687                                          struct packet_type *pt,
 688                                          struct net_device *orig_dev);
 689
 690 extern int                      ip6_rcv_finish(struct sk_buff *skb);
 691
 692 /*
 693  *      upper-layer output functions
 694  */
 695 extern int                      ip6_xmit(struct sock *sk,
 696                                          struct sk_buff *skb,
 697                                          struct flowi6 *fl6,
 698                                          struct ipv6_txoptions *opt,
 699                                          int tclass);
 700
 701 extern int                      ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
 702
 703 extern int                      ip6_append_data(struct sock *sk,
 704                                                 int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb),
 705                                                 void *from,
 706                                                 int length,
 707                                                 int transhdrlen,
 708                                                 int hlimit,
 709                                                 int tclass,
 710                                                 struct ipv6_txoptions *opt,
 711                                                 struct flowi6 *fl6,
 712                                                 struct rt6_info *rt,
 713                                                 unsigned int flags,
 714                                                 int dontfrag);
 715
 716 extern int                      ip6_push_pending_frames(struct sock *sk);
 717
 718 extern void                     ip6_flush_pending_frames(struct sock *sk);
 719
 720 extern int                      ip6_dst_lookup(struct sock *sk,
 721                                                struct dst_entry **dst,
 722                                                struct flowi6 *fl6);
 723 extern struct dst_entry *       ip6_dst_lookup_flow(struct sock *sk,
 724                                                     struct flowi6 *fl6,
 725                                                     const struct in6_addr *final_dst,
 726                                                     bool can_sleep);
 727 extern struct dst_entry *       ip6_sk_dst_lookup_flow(struct sock *sk,
 728                                                        struct flowi6 *fl6,
 729                                                        const struct in6_addr *final_dst,
 730                                                        bool can_sleep);
 731 extern struct dst_entry *       ip6_blackhole_route(struct net *net,
 732                                                     struct dst_entry *orig_dst);
 733
 734 /*
 735  *      skb processing functions
 736  */
 737
 738 extern int                      ip6_output(struct sk_buff *skb);
 739 extern int                      ip6_forward(struct sk_buff *skb);
 740 extern int                      ip6_input(struct sk_buff *skb);
 741 extern int                      ip6_mc_input(struct sk_buff *skb);
 742
 743 extern int                      __ip6_local_out(struct sk_buff *skb);
 744 extern int                      ip6_local_out(struct sk_buff *skb);
 745
 746 /*
 747  *      Extension header (options) processing
 748  */
 749
 750 extern void                     ipv6_push_nfrag_opts(struct sk_buff *skb,
 751                                                      struct ipv6_txoptions *opt,
 752                                                      u8 *proto,
 753                                                      struct in6_addr **daddr_p);
 754 extern void                     ipv6_push_frag_opts(struct sk_buff *skb,
 755                                                     struct ipv6_txoptions *opt,
 756                                                     u8 *proto);
 757
 758 extern int                      ipv6_skip_exthdr(const struct sk_buff *, int start,
 759                                                  u8 *nexthdrp, __be16 *frag_offp);
 760
 761 extern bool                     ipv6_ext_hdr(u8 nexthdr);
 762
 763 enum {
 764         IP6_FH_F_FRAG           = (1 << 0),
 765         IP6_FH_F_AUTH           = (1 << 1),
 766         IP6_FH_F_SKIP_RH        = (1 << 2),
 767 };
 768
 769 /* find specified header and get offset to it */
 770 extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
 771                          int target, unsigned short *fragoff, int *fragflg);
 772
 773 extern int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);
 774
 775 extern struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
 776                                        const struct ipv6_txoptions *opt,
 777                                        struct in6_addr *orig);
 778
 779 /*
 780  *      socket options (ipv6_sockglue.c)
 781  */
 782
 783 extern int                      ipv6_setsockopt(struct sock *sk, int level,
 784                                                 int optname,
 785                                                 char __user *optval,
 786                                                 unsigned int optlen);
 787 extern int                      ipv6_getsockopt(struct sock *sk, int level,
 788                                                 int optname,
 789                                                 char __user *optval,
 790                                                 int __user *optlen);
 791 extern int                      compat_ipv6_setsockopt(struct sock *sk,
 792                                                 int level,
 793                                                 int optname,
 794                                                 char __user *optval,
 795                                                 unsigned int optlen);
 796 extern int                      compat_ipv6_getsockopt(struct sock *sk,
 797                                                 int level,
 798                                                 int optname,
 799                                                 char __user *optval,
 800                                                 int __user *optlen);
 801
 802 extern int                      ip6_datagram_connect(struct sock *sk,
 803                                                      struct sockaddr *addr, int addr_len);
 804
 805 extern int                      ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len);
 806 extern int                      ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len);
 807 extern void                     ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
 808                                                 u32 info, u8 *payload);
 809 extern void                     ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
 810 extern void                     ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
 811
 812 extern int inet6_release(struct socket *sock);
 813 extern int inet6_bind(struct socket *sock, struct sockaddr *uaddr,
 814                       int addr_len);
 815 extern int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 816                          int *uaddr_len, int peer);
 817 extern int inet6_ioctl(struct socket *sock, unsigned int cmd,
 818                        unsigned long arg);
 819
 820 extern int inet6_hash_connect(struct inet_timewait_death_row *death_row,
 821                               struct sock *sk);
 822
 823 /*
 824  * reassembly.c
 825  */
 826 extern const struct proto_ops inet6_stream_ops;
 827 extern const struct proto_ops inet6_dgram_ops;
 828
 829 struct group_source_req;
 830 struct group_filter;
 831
 832 extern int ip6_mc_source(int add, int omode, struct sock *sk,
 833                          struct group_source_req *pgsr);
 834 extern int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
 835 extern int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
 836                          struct group_filter __user *optval,
 837                          int __user *optlen);
 838 extern unsigned int inet6_hash_frag(__be32 id, const struct in6_addr *saddr,
 839                                     const struct in6_addr *daddr, u32 rnd);
 840
 841 #ifdef CONFIG_PROC_FS
 842 extern int  ac6_proc_init(struct net *net);
 843 extern void ac6_proc_exit(struct net *net);
 844 extern int  raw6_proc_init(void);
 845 extern void raw6_proc_exit(void);
 846 extern int  tcp6_proc_init(struct net *net);
 847 extern void tcp6_proc_exit(struct net *net);
 848 extern int  udp6_proc_init(struct net *net);
 849 extern void udp6_proc_exit(struct net *net);
 850 extern int  udplite6_proc_init(void);
 851 extern void udplite6_proc_exit(void);
 852 extern int  ipv6_misc_proc_init(void);
 853 extern void ipv6_misc_proc_exit(void);
 854 extern int snmp6_register_dev(struct inet6_dev *idev);
 855 extern int snmp6_unregister_dev(struct inet6_dev *idev);
 856
 857 #else
 858 static inline int ac6_proc_init(struct net *net) { return 0; }
 859 static inline void ac6_proc_exit(struct net *net) { }
 860 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
 861 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
 862 #endif
 863
 864 #ifdef CONFIG_SYSCTL
 865 extern struct ctl_table ipv6_route_table_template[];
 866 extern struct ctl_table ipv6_icmp_table_template[];
 867
 868 extern struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
 869 extern struct ctl_table *ipv6_route_sysctl_init(struct net *net);
 870 extern int ipv6_sysctl_register(void);
 871 extern void ipv6_sysctl_unregister(void);
 872 #endif
 873
 874 #endif /* _NET_IPV6_H */