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/flow_keys.h>
  23 #include <net/snmp.h>
  24
  25 #define SIN6_LEN_RFC2133        24
  26
  27 #define IPV6_MAXPLEN            65535
  28
  29 /*
  30  *      NextHeader field of IPv6 header
  31  */
  32
  33 #define NEXTHDR_HOP             0       /* Hop-by-hop option header. */
  34 #define NEXTHDR_TCP             6       /* TCP segment. */
  35 #define NEXTHDR_UDP             17      /* UDP message. */
  36 #define NEXTHDR_IPV6            41      /* IPv6 in IPv6 */
  37 #define NEXTHDR_ROUTING         43      /* Routing header. */
  38 #define NEXTHDR_FRAGMENT        44      /* Fragmentation/reassembly header. */
  39 #define NEXTHDR_GRE             47      /* GRE header. */
  40 #define NEXTHDR_ESP             50      /* Encapsulating security payload. */
  41 #define NEXTHDR_AUTH            51      /* Authentication header. */
  42 #define NEXTHDR_ICMP            58      /* ICMP for IPv6. */
  43 #define NEXTHDR_NONE            59      /* No next header */
  44 #define NEXTHDR_DEST            60      /* Destination options header. */
  45 #define NEXTHDR_SCTP            132     /* SCTP message. */
  46 #define NEXTHDR_MOBILITY        135     /* Mobility header. */
  47
  48 #define NEXTHDR_MAX             255
  49
  50
  51
  52 #define IPV6_DEFAULT_HOPLIMIT   64
  53 #define IPV6_DEFAULT_MCASTHOPS  1
  54
  55 /*
  56  *      Addr type
  57  *
  58  *      type    -       unicast | multicast
  59  *      scope   -       local   | site      | global
  60  *      v4      -       compat
  61  *      v4mapped
  62  *      any
  63  *      loopback
  64  */
  65
  66 #define IPV6_ADDR_ANY           0x0000U
  67
  68 #define IPV6_ADDR_UNICAST       0x0001U
  69 #define IPV6_ADDR_MULTICAST     0x0002U
  70
  71 #define IPV6_ADDR_LOOPBACK      0x0010U
  72 #define IPV6_ADDR_LINKLOCAL     0x0020U
  73 #define IPV6_ADDR_SITELOCAL     0x0040U
  74
  75 #define IPV6_ADDR_COMPATv4      0x0080U
  76
  77 #define IPV6_ADDR_SCOPE_MASK    0x00f0U
  78
  79 #define IPV6_ADDR_MAPPED        0x1000U
  80
  81 /*
  82  *      Addr scopes
  83  */
  84 #define IPV6_ADDR_MC_SCOPE(a)   \
  85         ((a)->s6_addr[1] & 0x0f)        /* nonstandard */
  86 #define __IPV6_ADDR_SCOPE_INVALID       -1
  87 #define IPV6_ADDR_SCOPE_NODELOCAL       0x01
  88 #define IPV6_ADDR_SCOPE_LINKLOCAL       0x02
  89 #define IPV6_ADDR_SCOPE_SITELOCAL       0x05
  90 #define IPV6_ADDR_SCOPE_ORGLOCAL        0x08
  91 #define IPV6_ADDR_SCOPE_GLOBAL          0x0e
  92
  93 /*
  94  *      Addr flags
  95  */
  96 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a)  \
  97         ((a)->s6_addr[1] & 0x10)
  98 #define IPV6_ADDR_MC_FLAG_PREFIX(a)     \
  99         ((a)->s6_addr[1] & 0x20)
 100 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a) \
 101         ((a)->s6_addr[1] & 0x40)
 102
 103 /*
 104  *      fragmentation header
 105  */
 106
 107 struct frag_hdr {
 108         __u8    nexthdr;
 109         __u8    reserved;
 110         __be16  frag_off;
 111         __be32  identification;
 112 };
 113
 114 #define IP6_MF          0x0001
 115 #define IP6_OFFSET      0xFFF8
 116
 117 #define IP6_REPLY_MARK(net, mark) \
 118         ((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
 119
 120 #include <net/sock.h>
 121
 122 /* sysctls */
 123 extern int sysctl_mld_max_msf;
 124 extern int sysctl_mld_qrv;
 125
 126 #define _DEVINC(net, statname, modifier, idev, field)                   \
 127 ({                                                                      \
 128         struct inet6_dev *_idev = (idev);                               \
 129         if (likely(_idev != NULL))                                      \
 130                 SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \
 131         SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
 132 })
 133
 134 /* per device counters are atomic_long_t */
 135 #define _DEVINCATOMIC(net, statname, modifier, idev, field)             \
 136 ({                                                                      \
 137         struct inet6_dev *_idev = (idev);                               \
 138         if (likely(_idev != NULL))                                      \
 139                 SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 140         SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
 141 })
 142
 143 /* per device and per net counters are atomic_long_t */
 144 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)               \
 145 ({                                                                      \
 146         struct inet6_dev *_idev = (idev);                               \
 147         if (likely(_idev != NULL))                                      \
 148                 SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 149         SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
 150 })
 151
 152 #define _DEVADD(net, statname, modifier, idev, field, val)              \
 153 ({                                                                      \
 154         struct inet6_dev *_idev = (idev);                               \
 155         if (likely(_idev != NULL))                                      \
 156                 SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \
 157         SNMP_ADD_STATS##modifier((net)->mib.statname##_statistics, (field), (val));\
 158 })
 159
 160 #define _DEVUPD(net, statname, modifier, idev, field, val)              \
 161 ({                                                                      \
 162         struct inet6_dev *_idev = (idev);                               \
 163         if (likely(_idev != NULL))                                      \
 164                 SNMP_UPD_PO_STATS##modifier((_idev)->stats.statname, field, (val)); \
 165         SNMP_UPD_PO_STATS##modifier((net)->mib.statname##_statistics, field, (val));\
 166 })
 167
 168 /* MIBs */
 169
 170 #define IP6_INC_STATS(net, idev,field)          \
 171                 _DEVINC(net, ipv6, 64, idev, field)
 172 #define IP6_INC_STATS_BH(net, idev,field)       \
 173                 _DEVINC(net, ipv6, 64_BH, idev, field)
 174 #define IP6_ADD_STATS(net, idev,field,val)      \
 175                 _DEVADD(net, ipv6, 64, idev, field, val)
 176 #define IP6_ADD_STATS_BH(net, idev,field,val)   \
 177                 _DEVADD(net, ipv6, 64_BH, idev, field, val)
 178 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
 179                 _DEVUPD(net, ipv6, 64, idev, field, val)
 180 #define IP6_UPD_PO_STATS_BH(net, idev,field,val)   \
 181                 _DEVUPD(net, ipv6, 64_BH, idev, field, val)
 182 #define ICMP6_INC_STATS(net, idev, field)       \
 183                 _DEVINCATOMIC(net, icmpv6, , idev, field)
 184 #define ICMP6_INC_STATS_BH(net, idev, field)    \
 185                 _DEVINCATOMIC(net, icmpv6, _BH, idev, field)
 186
 187 #define ICMP6MSGOUT_INC_STATS(net, idev, field)         \
 188         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 189 #define ICMP6MSGOUT_INC_STATS_BH(net, idev, field)      \
 190         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 191 #define ICMP6MSGIN_INC_STATS_BH(net, idev, field)       \
 192         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
 193
 194 struct ip6_ra_chain {
 195         struct ip6_ra_chain     *next;
 196         struct sock             *sk;
 197         int                     sel;
 198         void                    (*destructor)(struct sock *);
 199 };
 200
 201 extern struct ip6_ra_chain      *ip6_ra_chain;
 202 extern rwlock_t ip6_ra_lock;
 203
 204 /*
 205    This structure is prepared by protocol, when parsing
 206    ancillary data and passed to IPv6.
 207  */
 208
 209 struct ipv6_txoptions {
 210         atomic_t                refcnt;
 211         /* Length of this structure */
 212         int                     tot_len;
 213
 214         /* length of extension headers   */
 215
 216         __u16                   opt_flen;       /* after fragment hdr */
 217         __u16                   opt_nflen;      /* before fragment hdr */
 218
 219         struct ipv6_opt_hdr     *hopopt;
 220         struct ipv6_opt_hdr     *dst0opt;
 221         struct ipv6_rt_hdr      *srcrt; /* Routing Header */
 222         struct ipv6_opt_hdr     *dst1opt;
 223         struct rcu_head         rcu;
 224         /* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
 225 };
 226
 227 struct ip6_flowlabel {
 228         struct ip6_flowlabel __rcu *next;
 229         __be32                  label;
 230         atomic_t                users;
 231         struct in6_addr         dst;
 232         struct ipv6_txoptions   *opt;
 233         unsigned long           linger;
 234         struct rcu_head         rcu;
 235         u8                      share;
 236         union {
 237                 struct pid *pid;
 238                 kuid_t uid;
 239         } owner;
 240         unsigned long           lastuse;
 241         unsigned long           expires;
 242         struct net              *fl_net;
 243 };
 244
 245 #define IPV6_FLOWINFO_MASK      cpu_to_be32(0x0FFFFFFF)
 246 #define IPV6_FLOWLABEL_MASK     cpu_to_be32(0x000FFFFF)
 247 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
 248 #define IPV6_TCLASS_SHIFT       20
 249
 250 struct ipv6_fl_socklist {
 251         struct ipv6_fl_socklist __rcu   *next;
 252         struct ip6_flowlabel            *fl;
 253         struct rcu_head                 rcu;
 254 };
 255
 256 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
 257 {
 258         struct ipv6_txoptions *opt;
 259
 260         rcu_read_lock();
 261         opt = rcu_dereference(np->opt);
 262         if (opt && !atomic_inc_not_zero(&opt->refcnt))
 263                 opt = NULL;
 264         rcu_read_unlock();
 265         return opt;
 266 }
 267
 268 static inline void txopt_put(struct ipv6_txoptions *opt)
 269 {
 270         if (opt && atomic_dec_and_test(&opt->refcnt))
 271                 kfree_rcu(opt, rcu);
 272 }
 273
 274 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
 275 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
 276                                          struct ip6_flowlabel *fl,
 277                                          struct ipv6_txoptions *fopt);
 278 void fl6_free_socklist(struct sock *sk);
 279 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
 280 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
 281                            int flags);
 282 int ip6_flowlabel_init(void);
 283 void ip6_flowlabel_cleanup(void);
 284
 285 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
 286 {
 287         if (fl)
 288                 atomic_dec(&fl->users);
 289 }
 290
 291 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
 292
 293 int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
 294                                struct icmp6hdr *thdr, int len);
 295
 296 int ip6_ra_control(struct sock *sk, int sel);
 297
 298 int ipv6_parse_hopopts(struct sk_buff *skb);
 299
 300 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
 301                                         struct ipv6_txoptions *opt);
 302 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
 303                                           struct ipv6_txoptions *opt,
 304                                           int newtype,
 305                                           struct ipv6_opt_hdr __user *newopt,
 306                                           int newoptlen);
 307 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
 308                                           struct ipv6_txoptions *opt);
 309
 310 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
 311                        const struct inet6_skb_parm *opt);
 312
 313 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 314 {
 315         /* If forwarding is enabled, RA are not accepted unless the special
 316          * hybrid mode (accept_ra=2) is enabled.
 317          */
 318         return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
 319             idev->cnf.accept_ra;
 320 }
 321
 322 #if IS_ENABLED(CONFIG_IPV6)
 323 static inline int ip6_frag_mem(struct net *net)
 324 {
 325         return sum_frag_mem_limit(&net->ipv6.frags);
 326 }
 327 #endif
 328
 329 #define IPV6_FRAG_HIGH_THRESH   (4 * 1024*1024) /* 4194304 */
 330 #define IPV6_FRAG_LOW_THRESH    (3 * 1024*1024) /* 3145728 */
 331 #define IPV6_FRAG_TIMEOUT       (60 * HZ)       /* 60 seconds */
 332
 333 int __ipv6_addr_type(const struct in6_addr *addr);
 334 static inline int ipv6_addr_type(const struct in6_addr *addr)
 335 {
 336         return __ipv6_addr_type(addr) & 0xffff;
 337 }
 338
 339 static inline int ipv6_addr_scope(const struct in6_addr *addr)
 340 {
 341         return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
 342 }
 343
 344 static inline int __ipv6_addr_src_scope(int type)
 345 {
 346         return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
 347 }
 348
 349 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
 350 {
 351         return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
 352 }
 353
 354 static inline bool __ipv6_addr_needs_scope_id(int type)
 355 {
 356         return type & IPV6_ADDR_LINKLOCAL ||
 357                (type & IPV6_ADDR_MULTICAST &&
 358                 (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
 359 }
 360
 361 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
 362 {
 363         return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
 364 }
 365
 366 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
 367 {
 368         return memcmp(a1, a2, sizeof(struct in6_addr));
 369 }
 370
 371 static inline bool
 372 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
 373                      const struct in6_addr *a2)
 374 {
 375 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 376         const unsigned long *ul1 = (const unsigned long *)a1;
 377         const unsigned long *ulm = (const unsigned long *)m;
 378         const unsigned long *ul2 = (const unsigned long *)a2;
 379
 380         return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
 381                   ((ul1[1] ^ ul2[1]) & ulm[1]));
 382 #else
 383         return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
 384                   ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
 385                   ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
 386                   ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
 387 #endif
 388 }
 389
 390 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
 391                                     const struct in6_addr *addr,
 392                                     int plen)
 393 {
 394         /* caller must guarantee 0 <= plen <= 128 */
 395         int o = plen >> 3,
 396             b = plen & 0x7;
 397
 398         memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
 399         memcpy(pfx->s6_addr, addr, o);
 400         if (b != 0)
 401                 pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
 402 }
 403
 404 static inline void __ipv6_addr_set_half(__be32 *addr,
 405                                         __be32 wh, __be32 wl)
 406 {
 407 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 408 #if defined(__BIG_ENDIAN)
 409         if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
 410                 *(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
 411                 return;
 412         }
 413 #elif defined(__LITTLE_ENDIAN)
 414         if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
 415                 *(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
 416                 return;
 417         }
 418 #endif
 419 #endif
 420         addr[0] = wh;
 421         addr[1] = wl;
 422 }
 423
 424 static inline void ipv6_addr_set(struct in6_addr *addr,
 425                                      __be32 w1, __be32 w2,
 426                                      __be32 w3, __be32 w4)
 427 {
 428         __ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
 429         __ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
 430 }
 431
 432 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
 433                                    const struct in6_addr *a2)
 434 {
 435 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 436         const unsigned long *ul1 = (const unsigned long *)a1;
 437         const unsigned long *ul2 = (const unsigned long *)a2;
 438
 439         return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
 440 #else
 441         return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
 442                 (a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
 443                 (a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
 444                 (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
 445 #endif
 446 }
 447
 448 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 449 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
 450                                               const __be64 *a2,
 451                                               unsigned int len)
 452 {
 453         if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
 454                 return false;
 455         return true;
 456 }
 457
 458 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 459                                      const struct in6_addr *addr2,
 460                                      unsigned int prefixlen)
 461 {
 462         const __be64 *a1 = (const __be64 *)addr1;
 463         const __be64 *a2 = (const __be64 *)addr2;
 464
 465         if (prefixlen >= 64) {
 466                 if (a1[0] ^ a2[0])
 467                         return false;
 468                 return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
 469         }
 470         return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
 471 }
 472 #else
 473 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 474                                      const struct in6_addr *addr2,
 475                                      unsigned int prefixlen)
 476 {
 477         const __be32 *a1 = addr1->s6_addr32;
 478         const __be32 *a2 = addr2->s6_addr32;
 479         unsigned int pdw, pbi;
 480
 481         /* check complete u32 in prefix */
 482         pdw = prefixlen >> 5;
 483         if (pdw && memcmp(a1, a2, pdw << 2))
 484                 return false;
 485
 486         /* check incomplete u32 in prefix */
 487         pbi = prefixlen & 0x1f;
 488         if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
 489                 return false;
 490
 491         return true;
 492 }
 493 #endif
 494
 495 struct inet_frag_queue;
 496
 497 enum ip6_defrag_users {
 498         IP6_DEFRAG_LOCAL_DELIVER,
 499         IP6_DEFRAG_CONNTRACK_IN,
 500         __IP6_DEFRAG_CONNTRACK_IN       = IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
 501         IP6_DEFRAG_CONNTRACK_OUT,
 502         __IP6_DEFRAG_CONNTRACK_OUT      = IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
 503         IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
 504         __IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
 505 };
 506
 507 struct ip6_create_arg {
 508         __be32 id;
 509         u32 user;
 510         const struct in6_addr *src;
 511         const struct in6_addr *dst;
 512         int iif;
 513         u8 ecn;
 514 };
 515
 516 void ip6_frag_init(struct inet_frag_queue *q, const void *a);
 517 bool ip6_frag_match(const struct inet_frag_queue *q, const void *a);
 518
 519 /*
 520  *      Equivalent of ipv4 struct ip
 521  */
 522 struct frag_queue {
 523         struct inet_frag_queue  q;
 524
 525         __be32                  id;             /* fragment id          */
 526         u32                     user;
 527         struct in6_addr         saddr;
 528         struct in6_addr         daddr;
 529
 530         int                     iif;
 531         unsigned int            csum;
 532         __u16                   nhoffset;
 533         u8                      ecn;
 534 };
 535
 536 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
 537                            struct inet_frags *frags);
 538
 539 static inline bool ipv6_addr_any(const struct in6_addr *a)
 540 {
 541 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 542         const unsigned long *ul = (const unsigned long *)a;
 543
 544         return (ul[0] | ul[1]) == 0UL;
 545 #else
 546         return (a->s6_addr32[0] | a->s6_addr32[1] |
 547                 a->s6_addr32[2] | a->s6_addr32[3]) == 0;
 548 #endif
 549 }
 550
 551 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
 552 {
 553 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 554         const unsigned long *ul = (const unsigned long *)a;
 555         unsigned long x = ul[0] ^ ul[1];
 556
 557         return (u32)(x ^ (x >> 32));
 558 #else
 559         return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
 560                              a->s6_addr32[2] ^ a->s6_addr32[3]);
 561 #endif
 562 }
 563
 564 /* more secured version of ipv6_addr_hash() */
 565 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
 566 {
 567         u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
 568
 569         return jhash_3words(v,
 570                             (__force u32)a->s6_addr32[2],
 571                             (__force u32)a->s6_addr32[3],
 572                             initval);
 573 }
 574
 575 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
 576 {
 577 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 578         const __be64 *be = (const __be64 *)a;
 579
 580         return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
 581 #else
 582         return (a->s6_addr32[0] | a->s6_addr32[1] |
 583                 a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
 584 #endif
 585 }
 586
 587 /*
 588  * Note that we must __force cast these to unsigned long to make sparse happy,
 589  * since all of the endian-annotated types are fixed size regardless of arch.
 590  */
 591 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
 592 {
 593         return (
 594 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 595                 *(unsigned long *)a |
 596 #else
 597                 (__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
 598 #endif
 599                 (__force unsigned long)(a->s6_addr32[2] ^
 600                                         cpu_to_be32(0x0000ffff))) == 0UL;
 601 }
 602
 603 /*
 604  * Check for a RFC 4843 ORCHID address
 605  * (Overlay Routable Cryptographic Hash Identifiers)
 606  */
 607 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
 608 {
 609         return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
 610 }
 611
 612 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
 613 {
 614         return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
 615 }
 616
 617 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
 618                                           struct in6_addr *v4mapped)
 619 {
 620         ipv6_addr_set(v4mapped,
 621                         0, 0,
 622                         htonl(0x0000FFFF),
 623                         addr);
 624 }
 625
 626 /*
 627  * find the first different bit between two addresses
 628  * length of address must be a multiple of 32bits
 629  */
 630 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
 631 {
 632         const __be32 *a1 = token1, *a2 = token2;
 633         int i;
 634
 635         addrlen >>= 2;
 636
 637         for (i = 0; i < addrlen; i++) {
 638                 __be32 xb = a1[i] ^ a2[i];
 639                 if (xb)
 640                         return i * 32 + 31 - __fls(ntohl(xb));
 641         }
 642
 643         /*
 644          *      we should *never* get to this point since that
 645          *      would mean the addrs are equal
 646          *
 647          *      However, we do get to it 8) And exacly, when
 648          *      addresses are equal 8)
 649          *
 650          *      ip route add 1111::/128 via ...
 651          *      ip route add 1111::/64 via ...
 652          *      and we are here.
 653          *
 654          *      Ideally, this function should stop comparison
 655          *      at prefix length. It does not, but it is still OK,
 656          *      if returned value is greater than prefix length.
 657          *                                      --ANK (980803)
 658          */
 659         return addrlen << 5;
 660 }
 661
 662 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 663 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
 664 {
 665         const __be64 *a1 = token1, *a2 = token2;
 666         int i;
 667
 668         addrlen >>= 3;
 669
 670         for (i = 0; i < addrlen; i++) {
 671                 __be64 xb = a1[i] ^ a2[i];
 672                 if (xb)
 673                         return i * 64 + 63 - __fls(be64_to_cpu(xb));
 674         }
 675
 676         return addrlen << 6;
 677 }
 678 #endif
 679
 680 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
 681 {
 682 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 683         if (__builtin_constant_p(addrlen) && !(addrlen & 7))
 684                 return __ipv6_addr_diff64(token1, token2, addrlen);
 685 #endif
 686         return __ipv6_addr_diff32(token1, token2, addrlen);
 687 }
 688
 689 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
 690 {
 691         return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
 692 }
 693
 694 void ipv6_proxy_select_ident(struct sk_buff *skb);
 695
 696 int ip6_dst_hoplimit(struct dst_entry *dst);
 697
 698 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
 699                                       struct dst_entry *dst)
 700 {
 701         int hlimit;
 702
 703         if (ipv6_addr_is_multicast(&fl6->daddr))
 704                 hlimit = np->mcast_hops;
 705         else
 706                 hlimit = np->hop_limit;
 707         if (hlimit < 0)
 708                 hlimit = ip6_dst_hoplimit(dst);
 709         return hlimit;
 710 }
 711
 712 #if IS_ENABLED(CONFIG_IPV6)
 713 static inline void ip6_set_txhash(struct sock *sk)
 714 {
 715         struct inet_sock *inet = inet_sk(sk);
 716         struct ipv6_pinfo *np = inet6_sk(sk);
 717         struct flow_keys keys;
 718
 719         keys.src = (__force __be32)ipv6_addr_hash(&np->saddr);
 720         keys.dst = (__force __be32)ipv6_addr_hash(&sk->sk_v6_daddr);
 721         keys.port16[0] = inet->inet_sport;
 722         keys.port16[1] = inet->inet_dport;
 723
 724         sk->sk_txhash = flow_hash_from_keys(&keys);
 725 }
 726
 727 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 728                                         __be32 flowlabel, bool autolabel)
 729 {
 730         if (!flowlabel && (autolabel || net->ipv6.sysctl.auto_flowlabels)) {
 731                 __be32 hash;
 732
 733                 hash = skb_get_hash(skb);
 734
 735                 /* Since this is being sent on the wire obfuscate hash a bit
 736                  * to minimize possbility that any useful information to an
 737                  * attacker is leaked. Only lower 20 bits are relevant.
 738                  */
 739                 hash ^= hash >> 12;
 740
 741                 flowlabel = hash & IPV6_FLOWLABEL_MASK;
 742         }
 743
 744         return flowlabel;
 745 }
 746 #else
 747 static inline void ip6_set_txhash(struct sock *sk) { }
 748 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 749                                         __be32 flowlabel, bool autolabel)
 750 {
 751         return flowlabel;
 752 }
 753 #endif
 754
 755
 756 /*
 757  *      Header manipulation
 758  */
 759 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
 760                                 __be32 flowlabel)
 761 {
 762         *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
 763 }
 764
 765 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
 766 {
 767         return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
 768 }
 769
 770 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
 771 {
 772         return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
 773 }
 774
 775 static inline u8 ip6_tclass(__be32 flowinfo)
 776 {
 777         return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
 778 }
 779 /*
 780  *      Prototypes exported by ipv6
 781  */
 782
 783 /*
 784  *      rcv function (called from netdevice level)
 785  */
 786
 787 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
 788              struct packet_type *pt, struct net_device *orig_dev);
 789
 790 int ip6_rcv_finish(struct sk_buff *skb);
 791
 792 /*
 793  *      upper-layer output functions
 794  */
 795 int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
 796              struct ipv6_txoptions *opt, int tclass);
 797
 798 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
 799
 800 int ip6_append_data(struct sock *sk,
 801                     int getfrag(void *from, char *to, int offset, int len,
 802                                 int odd, struct sk_buff *skb),
 803                     void *from, int length, int transhdrlen, int hlimit,
 804                     int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6,
 805                     struct rt6_info *rt, unsigned int flags, int dontfrag);
 806
 807 int ip6_push_pending_frames(struct sock *sk);
 808
 809 void ip6_flush_pending_frames(struct sock *sk);
 810
 811 int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6);
 812 struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 813                                       const struct in6_addr *final_dst);
 814 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 815                                          const struct in6_addr *final_dst);
 816 struct dst_entry *ip6_blackhole_route(struct net *net,
 817                                       struct dst_entry *orig_dst);
 818
 819 /*
 820  *      skb processing functions
 821  */
 822
 823 int ip6_output(struct sock *sk, struct sk_buff *skb);
 824 int ip6_forward(struct sk_buff *skb);
 825 int ip6_input(struct sk_buff *skb);
 826 int ip6_mc_input(struct sk_buff *skb);
 827
 828 int __ip6_local_out(struct sk_buff *skb);
 829 int ip6_local_out(struct sk_buff *skb);
 830
 831 /*
 832  *      Extension header (options) processing
 833  */
 834
 835 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
 836                           u8 *proto, struct in6_addr **daddr_p);
 837 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
 838                          u8 *proto);
 839
 840 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
 841                      __be16 *frag_offp);
 842
 843 bool ipv6_ext_hdr(u8 nexthdr);
 844
 845 enum {
 846         IP6_FH_F_FRAG           = (1 << 0),
 847         IP6_FH_F_AUTH           = (1 << 1),
 848         IP6_FH_F_SKIP_RH        = (1 << 2),
 849 };
 850
 851 /* find specified header and get offset to it */
 852 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
 853                   unsigned short *fragoff, int *fragflg);
 854
 855 int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);
 856
 857 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
 858                                 const struct ipv6_txoptions *opt,
 859                                 struct in6_addr *orig);
 860
 861 /*
 862  *      socket options (ipv6_sockglue.c)
 863  */
 864
 865 int ipv6_setsockopt(struct sock *sk, int level, int optname,
 866                     char __user *optval, unsigned int optlen);
 867 int ipv6_getsockopt(struct sock *sk, int level, int optname,
 868                     char __user *optval, int __user *optlen);
 869 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
 870                            char __user *optval, unsigned int optlen);
 871 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
 872                            char __user *optval, int __user *optlen);
 873
 874 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
 875 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
 876                                  int addr_len);
 877
 878 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
 879                     int *addr_len);
 880 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
 881                      int *addr_len);
 882 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
 883                      u32 info, u8 *payload);
 884 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
 885 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
 886
 887 int inet6_release(struct socket *sock);
 888 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
 889 int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
 890                   int peer);
 891 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
 892
 893 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
 894                               struct sock *sk);
 895
 896 /*
 897  * reassembly.c
 898  */
 899 extern const struct proto_ops inet6_stream_ops;
 900 extern const struct proto_ops inet6_dgram_ops;
 901
 902 struct group_source_req;
 903 struct group_filter;
 904
 905 int ip6_mc_source(int add, int omode, struct sock *sk,
 906                   struct group_source_req *pgsr);
 907 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
 908 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
 909                   struct group_filter __user *optval, int __user *optlen);
 910
 911 #ifdef CONFIG_PROC_FS
 912 int ac6_proc_init(struct net *net);
 913 void ac6_proc_exit(struct net *net);
 914 int raw6_proc_init(void);
 915 void raw6_proc_exit(void);
 916 int tcp6_proc_init(struct net *net);
 917 void tcp6_proc_exit(struct net *net);
 918 int udp6_proc_init(struct net *net);
 919 void udp6_proc_exit(struct net *net);
 920 int udplite6_proc_init(void);
 921 void udplite6_proc_exit(void);
 922 int ipv6_misc_proc_init(void);
 923 void ipv6_misc_proc_exit(void);
 924 int snmp6_register_dev(struct inet6_dev *idev);
 925 int snmp6_unregister_dev(struct inet6_dev *idev);
 926
 927 #else
 928 static inline int ac6_proc_init(struct net *net) { return 0; }
 929 static inline void ac6_proc_exit(struct net *net) { }
 930 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
 931 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
 932 #endif
 933
 934 #ifdef CONFIG_SYSCTL
 935 extern struct ctl_table ipv6_route_table_template[];
 936
 937 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
 938 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
 939 int ipv6_sysctl_register(void);
 940 void ipv6_sysctl_unregister(void);
 941 #endif
 942
 943 #endif /* _NET_IPV6_H */