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 #define IPV6_DEFAULT_HOPLIMIT   64
  51 #define IPV6_DEFAULT_MCASTHOPS  1
  52
  53 /*
  54  *      Addr type
  55  *
  56  *      type    -       unicast | multicast
  57  *      scope   -       local   | site      | global
  58  *      v4      -       compat
  59  *      v4mapped
  60  *      any
  61  *      loopback
  62  */
  63
  64 #define IPV6_ADDR_ANY           0x0000U
  65
  66 #define IPV6_ADDR_UNICAST       0x0001U
  67 #define IPV6_ADDR_MULTICAST     0x0002U
  68
  69 #define IPV6_ADDR_LOOPBACK      0x0010U
  70 #define IPV6_ADDR_LINKLOCAL     0x0020U
  71 #define IPV6_ADDR_SITELOCAL     0x0040U
  72
  73 #define IPV6_ADDR_COMPATv4      0x0080U
  74
  75 #define IPV6_ADDR_SCOPE_MASK    0x00f0U
  76
  77 #define IPV6_ADDR_MAPPED        0x1000U
  78
  79 /*
  80  *      Addr scopes
  81  */
  82 #define IPV6_ADDR_MC_SCOPE(a)   \
  83         ((a)->s6_addr[1] & 0x0f)        /* nonstandard */
  84 #define __IPV6_ADDR_SCOPE_INVALID       -1
  85 #define IPV6_ADDR_SCOPE_NODELOCAL       0x01
  86 #define IPV6_ADDR_SCOPE_LINKLOCAL       0x02
  87 #define IPV6_ADDR_SCOPE_SITELOCAL       0x05
  88 #define IPV6_ADDR_SCOPE_ORGLOCAL        0x08
  89 #define IPV6_ADDR_SCOPE_GLOBAL          0x0e
  90
  91 /*
  92  *      Addr flags
  93  */
  94 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a)  \
  95         ((a)->s6_addr[1] & 0x10)
  96 #define IPV6_ADDR_MC_FLAG_PREFIX(a)     \
  97         ((a)->s6_addr[1] & 0x20)
  98 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a) \
  99         ((a)->s6_addr[1] & 0x40)
 100
 101 /*
 102  *      fragmentation header
 103  */
 104
 105 struct frag_hdr {
 106         __u8    nexthdr;
 107         __u8    reserved;
 108         __be16  frag_off;
 109         __be32  identification;
 110 };
 111
 112 #define IP6_MF          0x0001
 113 #define IP6_OFFSET      0xFFF8
 114
 115 #define IP6_REPLY_MARK(net, mark) \
 116         ((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
 117
 118 #include <net/sock.h>
 119
 120 /* sysctls */
 121 extern int sysctl_mld_max_msf;
 122 extern int sysctl_mld_qrv;
 123
 124 #define _DEVINC(net, statname, modifier, idev, field)                   \
 125 ({                                                                      \
 126         struct inet6_dev *_idev = (idev);                               \
 127         if (likely(_idev != NULL))                                      \
 128                 SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \
 129         SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
 130 })
 131
 132 /* per device counters are atomic_long_t */
 133 #define _DEVINCATOMIC(net, statname, modifier, idev, field)             \
 134 ({                                                                      \
 135         struct inet6_dev *_idev = (idev);                               \
 136         if (likely(_idev != NULL))                                      \
 137                 SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 138         SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
 139 })
 140
 141 /* per device and per net counters are atomic_long_t */
 142 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)               \
 143 ({                                                                      \
 144         struct inet6_dev *_idev = (idev);                               \
 145         if (likely(_idev != NULL))                                      \
 146                 SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 147         SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
 148 })
 149
 150 #define _DEVADD(net, statname, modifier, idev, field, val)              \
 151 ({                                                                      \
 152         struct inet6_dev *_idev = (idev);                               \
 153         if (likely(_idev != NULL))                                      \
 154                 SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \
 155         SNMP_ADD_STATS##modifier((net)->mib.statname##_statistics, (field), (val));\
 156 })
 157
 158 #define _DEVUPD(net, statname, modifier, idev, field, val)              \
 159 ({                                                                      \
 160         struct inet6_dev *_idev = (idev);                               \
 161         if (likely(_idev != NULL))                                      \
 162                 SNMP_UPD_PO_STATS##modifier((_idev)->stats.statname, field, (val)); \
 163         SNMP_UPD_PO_STATS##modifier((net)->mib.statname##_statistics, field, (val));\
 164 })
 165
 166 /* MIBs */
 167
 168 #define IP6_INC_STATS(net, idev,field)          \
 169                 _DEVINC(net, ipv6, 64, idev, field)
 170 #define IP6_INC_STATS_BH(net, idev,field)       \
 171                 _DEVINC(net, ipv6, 64_BH, idev, field)
 172 #define IP6_ADD_STATS(net, idev,field,val)      \
 173                 _DEVADD(net, ipv6, 64, idev, field, val)
 174 #define IP6_ADD_STATS_BH(net, idev,field,val)   \
 175                 _DEVADD(net, ipv6, 64_BH, idev, field, val)
 176 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
 177                 _DEVUPD(net, ipv6, 64, idev, field, val)
 178 #define IP6_UPD_PO_STATS_BH(net, idev,field,val)   \
 179                 _DEVUPD(net, ipv6, 64_BH, idev, field, val)
 180 #define ICMP6_INC_STATS(net, idev, field)       \
 181                 _DEVINCATOMIC(net, icmpv6, , idev, field)
 182 #define ICMP6_INC_STATS_BH(net, idev, field)    \
 183                 _DEVINCATOMIC(net, icmpv6, _BH, idev, field)
 184
 185 #define ICMP6MSGOUT_INC_STATS(net, idev, field)         \
 186         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 187 #define ICMP6MSGOUT_INC_STATS_BH(net, idev, field)      \
 188         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 189 #define ICMP6MSGIN_INC_STATS_BH(net, idev, field)       \
 190         _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
 191
 192 struct ip6_ra_chain {
 193         struct ip6_ra_chain     *next;
 194         struct sock             *sk;
 195         int                     sel;
 196         void                    (*destructor)(struct sock *);
 197 };
 198
 199 extern struct ip6_ra_chain      *ip6_ra_chain;
 200 extern rwlock_t ip6_ra_lock;
 201
 202 /*
 203    This structure is prepared by protocol, when parsing
 204    ancillary data and passed to IPv6.
 205  */
 206
 207 struct ipv6_txoptions {
 208         atomic_t                refcnt;
 209         /* Length of this structure */
 210         int                     tot_len;
 211
 212         /* length of extension headers   */
 213
 214         __u16                   opt_flen;       /* after fragment hdr */
 215         __u16                   opt_nflen;      /* before fragment hdr */
 216
 217         struct ipv6_opt_hdr     *hopopt;
 218         struct ipv6_opt_hdr     *dst0opt;
 219         struct ipv6_rt_hdr      *srcrt; /* Routing Header */
 220         struct ipv6_opt_hdr     *dst1opt;
 221         struct rcu_head         rcu;
 222         /* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
 223 };
 224
 225 struct ip6_flowlabel {
 226         struct ip6_flowlabel __rcu *next;
 227         __be32                  label;
 228         atomic_t                users;
 229         struct in6_addr         dst;
 230         struct ipv6_txoptions   *opt;
 231         unsigned long           linger;
 232         struct rcu_head         rcu;
 233         u8                      share;
 234         union {
 235                 struct pid *pid;
 236                 kuid_t uid;
 237         } owner;
 238         unsigned long           lastuse;
 239         unsigned long           expires;
 240         struct net              *fl_net;
 241 };
 242
 243 #define IPV6_FLOWINFO_MASK      cpu_to_be32(0x0FFFFFFF)
 244 #define IPV6_FLOWLABEL_MASK     cpu_to_be32(0x000FFFFF)
 245 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
 246 #define IPV6_TCLASS_SHIFT       20
 247
 248 struct ipv6_fl_socklist {
 249         struct ipv6_fl_socklist __rcu   *next;
 250         struct ip6_flowlabel            *fl;
 251         struct rcu_head                 rcu;
 252 };
 253
 254 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
 255 {
 256         struct ipv6_txoptions *opt;
 257
 258         rcu_read_lock();
 259         opt = rcu_dereference(np->opt);
 260         if (opt && !atomic_inc_not_zero(&opt->refcnt))
 261                 opt = NULL;
 262         rcu_read_unlock();
 263         return opt;
 264 }
 265
 266 static inline void txopt_put(struct ipv6_txoptions *opt)
 267 {
 268         if (opt && atomic_dec_and_test(&opt->refcnt))
 269                 kfree_rcu(opt, rcu);
 270 }
 271
 272 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
 273 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
 274                                          struct ip6_flowlabel *fl,
 275                                          struct ipv6_txoptions *fopt);
 276 void fl6_free_socklist(struct sock *sk);
 277 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
 278 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
 279                            int flags);
 280 int ip6_flowlabel_init(void);
 281 void ip6_flowlabel_cleanup(void);
 282
 283 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
 284 {
 285         if (fl)
 286                 atomic_dec(&fl->users);
 287 }
 288
 289 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
 290
 291 int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
 292                                struct icmp6hdr *thdr, int len);
 293
 294 int ip6_ra_control(struct sock *sk, int sel);
 295
 296 int ipv6_parse_hopopts(struct sk_buff *skb);
 297
 298 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
 299                                         struct ipv6_txoptions *opt);
 300 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
 301                                           struct ipv6_txoptions *opt,
 302                                           int newtype,
 303                                           struct ipv6_opt_hdr __user *newopt,
 304                                           int newoptlen);
 305 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
 306                                           struct ipv6_txoptions *opt);
 307
 308 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
 309                        const struct inet6_skb_parm *opt);
 310
 311 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 312 {
 313         /* If forwarding is enabled, RA are not accepted unless the special
 314          * hybrid mode (accept_ra=2) is enabled.
 315          */
 316         return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
 317             idev->cnf.accept_ra;
 318 }
 319
 320 #if IS_ENABLED(CONFIG_IPV6)
 321 static inline int ip6_frag_mem(struct net *net)
 322 {
 323         return sum_frag_mem_limit(&net->ipv6.frags);
 324 }
 325 #endif
 326
 327 #define IPV6_FRAG_HIGH_THRESH   (4 * 1024*1024) /* 4194304 */
 328 #define IPV6_FRAG_LOW_THRESH    (3 * 1024*1024) /* 3145728 */
 329 #define IPV6_FRAG_TIMEOUT       (60 * HZ)       /* 60 seconds */
 330
 331 int __ipv6_addr_type(const struct in6_addr *addr);
 332 static inline int ipv6_addr_type(const struct in6_addr *addr)
 333 {
 334         return __ipv6_addr_type(addr) & 0xffff;
 335 }
 336
 337 static inline int ipv6_addr_scope(const struct in6_addr *addr)
 338 {
 339         return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
 340 }
 341
 342 static inline int __ipv6_addr_src_scope(int type)
 343 {
 344         return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
 345 }
 346
 347 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
 348 {
 349         return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
 350 }
 351
 352 static inline bool __ipv6_addr_needs_scope_id(int type)
 353 {
 354         return type & IPV6_ADDR_LINKLOCAL ||
 355                (type & IPV6_ADDR_MULTICAST &&
 356                 (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
 357 }
 358
 359 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
 360 {
 361         return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
 362 }
 363
 364 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
 365 {
 366         return memcmp(a1, a2, sizeof(struct in6_addr));
 367 }
 368
 369 static inline bool
 370 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
 371                      const struct in6_addr *a2)
 372 {
 373 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 374         const unsigned long *ul1 = (const unsigned long *)a1;
 375         const unsigned long *ulm = (const unsigned long *)m;
 376         const unsigned long *ul2 = (const unsigned long *)a2;
 377
 378         return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
 379                   ((ul1[1] ^ ul2[1]) & ulm[1]));
 380 #else
 381         return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
 382                   ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
 383                   ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
 384                   ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
 385 #endif
 386 }
 387
 388 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
 389                                     const struct in6_addr *addr,
 390                                     int plen)
 391 {
 392         /* caller must guarantee 0 <= plen <= 128 */
 393         int o = plen >> 3,
 394             b = plen & 0x7;
 395
 396         memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
 397         memcpy(pfx->s6_addr, addr, o);
 398         if (b != 0)
 399                 pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
 400 }
 401
 402 static inline void __ipv6_addr_set_half(__be32 *addr,
 403                                         __be32 wh, __be32 wl)
 404 {
 405 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 406 #if defined(__BIG_ENDIAN)
 407         if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
 408                 *(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
 409                 return;
 410         }
 411 #elif defined(__LITTLE_ENDIAN)
 412         if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
 413                 *(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
 414                 return;
 415         }
 416 #endif
 417 #endif
 418         addr[0] = wh;
 419         addr[1] = wl;
 420 }
 421
 422 static inline void ipv6_addr_set(struct in6_addr *addr,
 423                                      __be32 w1, __be32 w2,
 424                                      __be32 w3, __be32 w4)
 425 {
 426         __ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
 427         __ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
 428 }
 429
 430 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
 431                                    const struct in6_addr *a2)
 432 {
 433 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 434         const unsigned long *ul1 = (const unsigned long *)a1;
 435         const unsigned long *ul2 = (const unsigned long *)a2;
 436
 437         return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
 438 #else
 439         return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
 440                 (a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
 441                 (a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
 442                 (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
 443 #endif
 444 }
 445
 446 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 447 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
 448                                               const __be64 *a2,
 449                                               unsigned int len)
 450 {
 451         if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
 452                 return false;
 453         return true;
 454 }
 455
 456 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 457                                      const struct in6_addr *addr2,
 458                                      unsigned int prefixlen)
 459 {
 460         const __be64 *a1 = (const __be64 *)addr1;
 461         const __be64 *a2 = (const __be64 *)addr2;
 462
 463         if (prefixlen >= 64) {
 464                 if (a1[0] ^ a2[0])
 465                         return false;
 466                 return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
 467         }
 468         return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
 469 }
 470 #else
 471 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 472                                      const struct in6_addr *addr2,
 473                                      unsigned int prefixlen)
 474 {
 475         const __be32 *a1 = addr1->s6_addr32;
 476         const __be32 *a2 = addr2->s6_addr32;
 477         unsigned int pdw, pbi;
 478
 479         /* check complete u32 in prefix */
 480         pdw = prefixlen >> 5;
 481         if (pdw && memcmp(a1, a2, pdw << 2))
 482                 return false;
 483
 484         /* check incomplete u32 in prefix */
 485         pbi = prefixlen & 0x1f;
 486         if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
 487                 return false;
 488
 489         return true;
 490 }
 491 #endif
 492
 493 struct inet_frag_queue;
 494
 495 enum ip6_defrag_users {
 496         IP6_DEFRAG_LOCAL_DELIVER,
 497         IP6_DEFRAG_CONNTRACK_IN,
 498         __IP6_DEFRAG_CONNTRACK_IN       = IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
 499         IP6_DEFRAG_CONNTRACK_OUT,
 500         __IP6_DEFRAG_CONNTRACK_OUT      = IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
 501         IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
 502         __IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
 503 };
 504
 505 struct ip6_create_arg {
 506         __be32 id;
 507         u32 user;
 508         const struct in6_addr *src;
 509         const struct in6_addr *dst;
 510         int iif;
 511         u8 ecn;
 512 };
 513
 514 void ip6_frag_init(struct inet_frag_queue *q, const void *a);
 515 bool ip6_frag_match(const struct inet_frag_queue *q, const void *a);
 516
 517 /*
 518  *      Equivalent of ipv4 struct ip
 519  */
 520 struct frag_queue {
 521         struct inet_frag_queue  q;
 522
 523         __be32                  id;             /* fragment id          */
 524         u32                     user;
 525         struct in6_addr         saddr;
 526         struct in6_addr         daddr;
 527
 528         int                     iif;
 529         unsigned int            csum;
 530         __u16                   nhoffset;
 531         u8                      ecn;
 532 };
 533
 534 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
 535                            struct inet_frags *frags);
 536
 537 static inline bool ipv6_addr_any(const struct in6_addr *a)
 538 {
 539 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 540         const unsigned long *ul = (const unsigned long *)a;
 541
 542         return (ul[0] | ul[1]) == 0UL;
 543 #else
 544         return (a->s6_addr32[0] | a->s6_addr32[1] |
 545                 a->s6_addr32[2] | a->s6_addr32[3]) == 0;
 546 #endif
 547 }
 548
 549 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
 550 {
 551 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 552         const unsigned long *ul = (const unsigned long *)a;
 553         unsigned long x = ul[0] ^ ul[1];
 554
 555         return (u32)(x ^ (x >> 32));
 556 #else
 557         return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
 558                              a->s6_addr32[2] ^ a->s6_addr32[3]);
 559 #endif
 560 }
 561
 562 /* more secured version of ipv6_addr_hash() */
 563 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
 564 {
 565         u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
 566
 567         return jhash_3words(v,
 568                             (__force u32)a->s6_addr32[2],
 569                             (__force u32)a->s6_addr32[3],
 570                             initval);
 571 }
 572
 573 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
 574 {
 575 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 576         const __be64 *be = (const __be64 *)a;
 577
 578         return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
 579 #else
 580         return (a->s6_addr32[0] | a->s6_addr32[1] |
 581                 a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
 582 #endif
 583 }
 584
 585 /*
 586  * Note that we must __force cast these to unsigned long to make sparse happy,
 587  * since all of the endian-annotated types are fixed size regardless of arch.
 588  */
 589 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
 590 {
 591         return (
 592 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 593                 *(unsigned long *)a |
 594 #else
 595                 (__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
 596 #endif
 597                 (__force unsigned long)(a->s6_addr32[2] ^
 598                                         cpu_to_be32(0x0000ffff))) == 0UL;
 599 }
 600
 601 /*
 602  * Check for a RFC 4843 ORCHID address
 603  * (Overlay Routable Cryptographic Hash Identifiers)
 604  */
 605 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
 606 {
 607         return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
 608 }
 609
 610 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
 611 {
 612         return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
 613 }
 614
 615 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
 616                                           struct in6_addr *v4mapped)
 617 {
 618         ipv6_addr_set(v4mapped,
 619                         0, 0,
 620                         htonl(0x0000FFFF),
 621                         addr);
 622 }
 623
 624 /*
 625  * find the first different bit between two addresses
 626  * length of address must be a multiple of 32bits
 627  */
 628 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
 629 {
 630         const __be32 *a1 = token1, *a2 = token2;
 631         int i;
 632
 633         addrlen >>= 2;
 634
 635         for (i = 0; i < addrlen; i++) {
 636                 __be32 xb = a1[i] ^ a2[i];
 637                 if (xb)
 638                         return i * 32 + 31 - __fls(ntohl(xb));
 639         }
 640
 641         /*
 642          *      we should *never* get to this point since that
 643          *      would mean the addrs are equal
 644          *
 645          *      However, we do get to it 8) And exacly, when
 646          *      addresses are equal 8)
 647          *
 648          *      ip route add 1111::/128 via ...
 649          *      ip route add 1111::/64 via ...
 650          *      and we are here.
 651          *
 652          *      Ideally, this function should stop comparison
 653          *      at prefix length. It does not, but it is still OK,
 654          *      if returned value is greater than prefix length.
 655          *                                      --ANK (980803)
 656          */
 657         return addrlen << 5;
 658 }
 659
 660 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 661 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
 662 {
 663         const __be64 *a1 = token1, *a2 = token2;
 664         int i;
 665
 666         addrlen >>= 3;
 667
 668         for (i = 0; i < addrlen; i++) {
 669                 __be64 xb = a1[i] ^ a2[i];
 670                 if (xb)
 671                         return i * 64 + 63 - __fls(be64_to_cpu(xb));
 672         }
 673
 674         return addrlen << 6;
 675 }
 676 #endif
 677
 678 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
 679 {
 680 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 681         if (__builtin_constant_p(addrlen) && !(addrlen & 7))
 682                 return __ipv6_addr_diff64(token1, token2, addrlen);
 683 #endif
 684         return __ipv6_addr_diff32(token1, token2, addrlen);
 685 }
 686
 687 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
 688 {
 689         return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
 690 }
 691
 692 void ipv6_select_ident(struct net *net, struct frag_hdr *fhdr,
 693                        struct rt6_info *rt);
 694 void ipv6_proxy_select_ident(struct net *net, 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                 u32 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 = (__force __be32)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 sock *sk, 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_send_skb(struct sk_buff *skb);
 812
 813 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
 814                                struct inet_cork_full *cork,
 815                                struct inet6_cork *v6_cork);
 816 struct sk_buff *ip6_make_skb(struct sock *sk,
 817                              int getfrag(void *from, char *to, int offset,
 818                                          int len, int odd, struct sk_buff *skb),
 819                              void *from, int length, int transhdrlen,
 820                              int hlimit, int tclass, struct ipv6_txoptions *opt,
 821                              struct flowi6 *fl6, struct rt6_info *rt,
 822                              unsigned int flags, int dontfrag);
 823
 824 static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
 825 {
 826         return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
 827                               &inet6_sk(sk)->cork);
 828 }
 829
 830 int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6);
 831 struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 832                                       const struct in6_addr *final_dst);
 833 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 834                                          const struct in6_addr *final_dst);
 835 struct dst_entry *ip6_blackhole_route(struct net *net,
 836                                       struct dst_entry *orig_dst);
 837
 838 /*
 839  *      skb processing functions
 840  */
 841
 842 int ip6_output(struct sock *sk, struct sk_buff *skb);
 843 int ip6_forward(struct sk_buff *skb);
 844 int ip6_input(struct sk_buff *skb);
 845 int ip6_mc_input(struct sk_buff *skb);
 846
 847 int __ip6_local_out(struct sk_buff *skb);
 848 int ip6_local_out_sk(struct sock *sk, struct sk_buff *skb);
 849 int ip6_local_out(struct sk_buff *skb);
 850
 851 /*
 852  *      Extension header (options) processing
 853  */
 854
 855 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
 856                           u8 *proto, struct in6_addr **daddr_p);
 857 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
 858                          u8 *proto);
 859
 860 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
 861                      __be16 *frag_offp);
 862
 863 bool ipv6_ext_hdr(u8 nexthdr);
 864
 865 enum {
 866         IP6_FH_F_FRAG           = (1 << 0),
 867         IP6_FH_F_AUTH           = (1 << 1),
 868         IP6_FH_F_SKIP_RH        = (1 << 2),
 869 };
 870
 871 /* find specified header and get offset to it */
 872 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
 873                   unsigned short *fragoff, int *fragflg);
 874
 875 int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);
 876
 877 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
 878                                 const struct ipv6_txoptions *opt,
 879                                 struct in6_addr *orig);
 880
 881 /*
 882  *      socket options (ipv6_sockglue.c)
 883  */
 884
 885 int ipv6_setsockopt(struct sock *sk, int level, int optname,
 886                     char __user *optval, unsigned int optlen);
 887 int ipv6_getsockopt(struct sock *sk, int level, int optname,
 888                     char __user *optval, int __user *optlen);
 889 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
 890                            char __user *optval, unsigned int optlen);
 891 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
 892                            char __user *optval, int __user *optlen);
 893
 894 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
 895 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
 896                                  int addr_len);
 897
 898 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
 899                     int *addr_len);
 900 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
 901                      int *addr_len);
 902 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
 903                      u32 info, u8 *payload);
 904 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
 905 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
 906
 907 int inet6_release(struct socket *sock);
 908 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
 909 int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
 910                   int peer);
 911 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
 912
 913 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
 914                               struct sock *sk);
 915
 916 /*
 917  * reassembly.c
 918  */
 919 extern const struct proto_ops inet6_stream_ops;
 920 extern const struct proto_ops inet6_dgram_ops;
 921
 922 struct group_source_req;
 923 struct group_filter;
 924
 925 int ip6_mc_source(int add, int omode, struct sock *sk,
 926                   struct group_source_req *pgsr);
 927 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
 928 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
 929                   struct group_filter __user *optval, int __user *optlen);
 930
 931 #ifdef CONFIG_PROC_FS
 932 int ac6_proc_init(struct net *net);
 933 void ac6_proc_exit(struct net *net);
 934 int raw6_proc_init(void);
 935 void raw6_proc_exit(void);
 936 int tcp6_proc_init(struct net *net);
 937 void tcp6_proc_exit(struct net *net);
 938 int udp6_proc_init(struct net *net);
 939 void udp6_proc_exit(struct net *net);
 940 int udplite6_proc_init(void);
 941 void udplite6_proc_exit(void);
 942 int ipv6_misc_proc_init(void);
 943 void ipv6_misc_proc_exit(void);
 944 int snmp6_register_dev(struct inet6_dev *idev);
 945 int snmp6_unregister_dev(struct inet6_dev *idev);
 946
 947 #else
 948 static inline int ac6_proc_init(struct net *net) { return 0; }
 949 static inline void ac6_proc_exit(struct net *net) { }
 950 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
 951 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
 952 #endif
 953
 954 #ifdef CONFIG_SYSCTL
 955 extern struct ctl_table ipv6_route_table_template[];
 956
 957 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
 958 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
 959 int ipv6_sysctl_register(void);
 960 void ipv6_sysctl_unregister(void);
 961 #endif
 962
 963 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
 964                       const struct in6_addr *addr);
 965 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
 966                       const struct in6_addr *addr);
 967 #endif /* _NET_IPV6_H */