linux/include/net/ipv6.h
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   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_dissector.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
 105struct 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 */
 121extern int sysctl_mld_max_msf;
 122extern int sysctl_mld_qrv;
 123
 124#define _DEVINC(net, statname, mod, idev, field)                        \
 125({                                                                      \
 126        struct inet6_dev *_idev = (idev);                               \
 127        if (likely(_idev != NULL))                                      \
 128                mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\
 129        mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\
 130})
 131
 132/* per device counters are atomic_long_t */
 133#define _DEVINCATOMIC(net, statname, mod, 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        mod##SNMP_INC_STATS((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, mod, idev, field, val)                   \
 151({                                                                      \
 152        struct inet6_dev *_idev = (idev);                               \
 153        if (likely(_idev != NULL))                                      \
 154                mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \
 155        mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\
 156})
 157
 158#define _DEVUPD(net, statname, mod, idev, field, val)                   \
 159({                                                                      \
 160        struct inet6_dev *_idev = (idev);                               \
 161        if (likely(_idev != NULL))                                      \
 162                mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \
 163        mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\
 164})
 165
 166/* MIBs */
 167
 168#define IP6_INC_STATS(net, idev,field)          \
 169                _DEVINC(net, ipv6, , idev, field)
 170#define __IP6_INC_STATS(net, idev,field)        \
 171                _DEVINC(net, ipv6, __, idev, field)
 172#define IP6_ADD_STATS(net, idev,field,val)      \
 173                _DEVADD(net, ipv6, , idev, field, val)
 174#define __IP6_ADD_STATS(net, idev,field,val)    \
 175                _DEVADD(net, ipv6, __, idev, field, val)
 176#define IP6_UPD_PO_STATS(net, idev,field,val)   \
 177                _DEVUPD(net, ipv6, , idev, field, val)
 178#define __IP6_UPD_PO_STATS(net, idev,field,val)   \
 179                _DEVUPD(net, ipv6, __, idev, field, val)
 180#define ICMP6_INC_STATS(net, idev, field)       \
 181                _DEVINCATOMIC(net, icmpv6, , idev, field)
 182#define __ICMP6_INC_STATS(net, idev, field)     \
 183                _DEVINCATOMIC(net, icmpv6, __, idev, field)
 184
 185#define ICMP6MSGOUT_INC_STATS(net, idev, field)         \
 186        _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 187#define ICMP6MSGIN_INC_STATS(net, idev, field)  \
 188        _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
 189
 190struct ip6_ra_chain {
 191        struct ip6_ra_chain     *next;
 192        struct sock             *sk;
 193        int                     sel;
 194        void                    (*destructor)(struct sock *);
 195};
 196
 197extern struct ip6_ra_chain      *ip6_ra_chain;
 198extern rwlock_t ip6_ra_lock;
 199
 200/*
 201   This structure is prepared by protocol, when parsing
 202   ancillary data and passed to IPv6.
 203 */
 204
 205struct ipv6_txoptions {
 206        atomic_t                refcnt;
 207        /* Length of this structure */
 208        int                     tot_len;
 209
 210        /* length of extension headers   */
 211
 212        __u16                   opt_flen;       /* after fragment hdr */
 213        __u16                   opt_nflen;      /* before fragment hdr */
 214
 215        struct ipv6_opt_hdr     *hopopt;
 216        struct ipv6_opt_hdr     *dst0opt;
 217        struct ipv6_rt_hdr      *srcrt; /* Routing Header */
 218        struct ipv6_opt_hdr     *dst1opt;
 219        struct rcu_head         rcu;
 220        /* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
 221};
 222
 223struct ip6_flowlabel {
 224        struct ip6_flowlabel __rcu *next;
 225        __be32                  label;
 226        atomic_t                users;
 227        struct in6_addr         dst;
 228        struct ipv6_txoptions   *opt;
 229        unsigned long           linger;
 230        struct rcu_head         rcu;
 231        u8                      share;
 232        union {
 233                struct pid *pid;
 234                kuid_t uid;
 235        } owner;
 236        unsigned long           lastuse;
 237        unsigned long           expires;
 238        struct net              *fl_net;
 239};
 240
 241#define IPV6_FLOWINFO_MASK              cpu_to_be32(0x0FFFFFFF)
 242#define IPV6_FLOWLABEL_MASK             cpu_to_be32(0x000FFFFF)
 243#define IPV6_FLOWLABEL_STATELESS_FLAG   cpu_to_be32(0x00080000)
 244
 245#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
 246#define IPV6_TCLASS_SHIFT       20
 247
 248struct ipv6_fl_socklist {
 249        struct ipv6_fl_socklist __rcu   *next;
 250        struct ip6_flowlabel            *fl;
 251        struct rcu_head                 rcu;
 252};
 253
 254struct ipcm6_cookie {
 255        __s16 hlimit;
 256        __s16 tclass;
 257        __s8  dontfrag;
 258        struct ipv6_txoptions *opt;
 259};
 260
 261static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
 262{
 263        struct ipv6_txoptions *opt;
 264
 265        rcu_read_lock();
 266        opt = rcu_dereference(np->opt);
 267        if (opt) {
 268                if (!atomic_inc_not_zero(&opt->refcnt))
 269                        opt = NULL;
 270                else
 271                        opt = rcu_pointer_handoff(opt);
 272        }
 273        rcu_read_unlock();
 274        return opt;
 275}
 276
 277static inline void txopt_put(struct ipv6_txoptions *opt)
 278{
 279        if (opt && atomic_dec_and_test(&opt->refcnt))
 280                kfree_rcu(opt, rcu);
 281}
 282
 283struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
 284struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
 285                                         struct ip6_flowlabel *fl,
 286                                         struct ipv6_txoptions *fopt);
 287void fl6_free_socklist(struct sock *sk);
 288int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
 289int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
 290                           int flags);
 291int ip6_flowlabel_init(void);
 292void ip6_flowlabel_cleanup(void);
 293
 294static inline void fl6_sock_release(struct ip6_flowlabel *fl)
 295{
 296        if (fl)
 297                atomic_dec(&fl->users);
 298}
 299
 300void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
 301
 302int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
 303                               struct icmp6hdr *thdr, int len);
 304
 305int ip6_ra_control(struct sock *sk, int sel);
 306
 307int ipv6_parse_hopopts(struct sk_buff *skb);
 308
 309struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
 310                                        struct ipv6_txoptions *opt);
 311struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
 312                                          struct ipv6_txoptions *opt,
 313                                          int newtype,
 314                                          struct ipv6_opt_hdr __user *newopt,
 315                                          int newoptlen);
 316struct ipv6_txoptions *
 317ipv6_renew_options_kern(struct sock *sk,
 318                        struct ipv6_txoptions *opt,
 319                        int newtype,
 320                        struct ipv6_opt_hdr *newopt,
 321                        int newoptlen);
 322struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
 323                                          struct ipv6_txoptions *opt);
 324
 325bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
 326                       const struct inet6_skb_parm *opt);
 327struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
 328                                           struct ipv6_txoptions *opt);
 329
 330static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 331{
 332        /* If forwarding is enabled, RA are not accepted unless the special
 333         * hybrid mode (accept_ra=2) is enabled.
 334         */
 335        return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
 336            idev->cnf.accept_ra;
 337}
 338
 339#if IS_ENABLED(CONFIG_IPV6)
 340static inline int ip6_frag_mem(struct net *net)
 341{
 342        return sum_frag_mem_limit(&net->ipv6.frags);
 343}
 344#endif
 345
 346#define IPV6_FRAG_HIGH_THRESH   (4 * 1024*1024) /* 4194304 */
 347#define IPV6_FRAG_LOW_THRESH    (3 * 1024*1024) /* 3145728 */
 348#define IPV6_FRAG_TIMEOUT       (60 * HZ)       /* 60 seconds */
 349
 350int __ipv6_addr_type(const struct in6_addr *addr);
 351static inline int ipv6_addr_type(const struct in6_addr *addr)
 352{
 353        return __ipv6_addr_type(addr) & 0xffff;
 354}
 355
 356static inline int ipv6_addr_scope(const struct in6_addr *addr)
 357{
 358        return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
 359}
 360
 361static inline int __ipv6_addr_src_scope(int type)
 362{
 363        return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
 364}
 365
 366static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
 367{
 368        return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
 369}
 370
 371static inline bool __ipv6_addr_needs_scope_id(int type)
 372{
 373        return type & IPV6_ADDR_LINKLOCAL ||
 374               (type & IPV6_ADDR_MULTICAST &&
 375                (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
 376}
 377
 378static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
 379{
 380        return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
 381}
 382
 383static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
 384{
 385        return memcmp(a1, a2, sizeof(struct in6_addr));
 386}
 387
 388static inline bool
 389ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
 390                     const struct in6_addr *a2)
 391{
 392#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 393        const unsigned long *ul1 = (const unsigned long *)a1;
 394        const unsigned long *ulm = (const unsigned long *)m;
 395        const unsigned long *ul2 = (const unsigned long *)a2;
 396
 397        return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
 398                  ((ul1[1] ^ ul2[1]) & ulm[1]));
 399#else
 400        return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
 401                  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
 402                  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
 403                  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
 404#endif
 405}
 406
 407static inline void ipv6_addr_prefix(struct in6_addr *pfx, 
 408                                    const struct in6_addr *addr,
 409                                    int plen)
 410{
 411        /* caller must guarantee 0 <= plen <= 128 */
 412        int o = plen >> 3,
 413            b = plen & 0x7;
 414
 415        memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
 416        memcpy(pfx->s6_addr, addr, o);
 417        if (b != 0)
 418                pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
 419}
 420
 421static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
 422                                         const struct in6_addr *pfx,
 423                                         int plen)
 424{
 425        /* caller must guarantee 0 <= plen <= 128 */
 426        int o = plen >> 3,
 427            b = plen & 0x7;
 428
 429        memcpy(addr->s6_addr, pfx, o);
 430        if (b != 0) {
 431                addr->s6_addr[o] &= ~(0xff00 >> b);
 432                addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
 433        }
 434}
 435
 436static inline void __ipv6_addr_set_half(__be32 *addr,
 437                                        __be32 wh, __be32 wl)
 438{
 439#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 440#if defined(__BIG_ENDIAN)
 441        if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
 442                *(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
 443                return;
 444        }
 445#elif defined(__LITTLE_ENDIAN)
 446        if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
 447                *(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
 448                return;
 449        }
 450#endif
 451#endif
 452        addr[0] = wh;
 453        addr[1] = wl;
 454}
 455
 456static inline void ipv6_addr_set(struct in6_addr *addr, 
 457                                     __be32 w1, __be32 w2,
 458                                     __be32 w3, __be32 w4)
 459{
 460        __ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
 461        __ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
 462}
 463
 464static inline bool ipv6_addr_equal(const struct in6_addr *a1,
 465                                   const struct in6_addr *a2)
 466{
 467#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 468        const unsigned long *ul1 = (const unsigned long *)a1;
 469        const unsigned long *ul2 = (const unsigned long *)a2;
 470
 471        return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
 472#else
 473        return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
 474                (a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
 475                (a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
 476                (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
 477#endif
 478}
 479
 480#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 481static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
 482                                              const __be64 *a2,
 483                                              unsigned int len)
 484{
 485        if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
 486                return false;
 487        return true;
 488}
 489
 490static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 491                                     const struct in6_addr *addr2,
 492                                     unsigned int prefixlen)
 493{
 494        const __be64 *a1 = (const __be64 *)addr1;
 495        const __be64 *a2 = (const __be64 *)addr2;
 496
 497        if (prefixlen >= 64) {
 498                if (a1[0] ^ a2[0])
 499                        return false;
 500                return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
 501        }
 502        return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
 503}
 504#else
 505static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 506                                     const struct in6_addr *addr2,
 507                                     unsigned int prefixlen)
 508{
 509        const __be32 *a1 = addr1->s6_addr32;
 510        const __be32 *a2 = addr2->s6_addr32;
 511        unsigned int pdw, pbi;
 512
 513        /* check complete u32 in prefix */
 514        pdw = prefixlen >> 5;
 515        if (pdw && memcmp(a1, a2, pdw << 2))
 516                return false;
 517
 518        /* check incomplete u32 in prefix */
 519        pbi = prefixlen & 0x1f;
 520        if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
 521                return false;
 522
 523        return true;
 524}
 525#endif
 526
 527struct inet_frag_queue;
 528
 529enum ip6_defrag_users {
 530        IP6_DEFRAG_LOCAL_DELIVER,
 531        IP6_DEFRAG_CONNTRACK_IN,
 532        __IP6_DEFRAG_CONNTRACK_IN       = IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
 533        IP6_DEFRAG_CONNTRACK_OUT,
 534        __IP6_DEFRAG_CONNTRACK_OUT      = IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
 535        IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
 536        __IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
 537};
 538
 539struct ip6_create_arg {
 540        __be32 id;
 541        u32 user;
 542        const struct in6_addr *src;
 543        const struct in6_addr *dst;
 544        int iif;
 545        u8 ecn;
 546};
 547
 548void ip6_frag_init(struct inet_frag_queue *q, const void *a);
 549bool ip6_frag_match(const struct inet_frag_queue *q, const void *a);
 550
 551/*
 552 *      Equivalent of ipv4 struct ip
 553 */
 554struct frag_queue {
 555        struct inet_frag_queue  q;
 556
 557        __be32                  id;             /* fragment id          */
 558        u32                     user;
 559        struct in6_addr         saddr;
 560        struct in6_addr         daddr;
 561
 562        int                     iif;
 563        unsigned int            csum;
 564        __u16                   nhoffset;
 565        u8                      ecn;
 566};
 567
 568void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
 569                           struct inet_frags *frags);
 570
 571static inline bool ipv6_addr_any(const struct in6_addr *a)
 572{
 573#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 574        const unsigned long *ul = (const unsigned long *)a;
 575
 576        return (ul[0] | ul[1]) == 0UL;
 577#else
 578        return (a->s6_addr32[0] | a->s6_addr32[1] |
 579                a->s6_addr32[2] | a->s6_addr32[3]) == 0;
 580#endif
 581}
 582
 583static inline u32 ipv6_addr_hash(const struct in6_addr *a)
 584{
 585#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 586        const unsigned long *ul = (const unsigned long *)a;
 587        unsigned long x = ul[0] ^ ul[1];
 588
 589        return (u32)(x ^ (x >> 32));
 590#else
 591        return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
 592                             a->s6_addr32[2] ^ a->s6_addr32[3]);
 593#endif
 594}
 595
 596/* more secured version of ipv6_addr_hash() */
 597static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
 598{
 599        u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
 600
 601        return jhash_3words(v,
 602                            (__force u32)a->s6_addr32[2],
 603                            (__force u32)a->s6_addr32[3],
 604                            initval);
 605}
 606
 607static inline bool ipv6_addr_loopback(const struct in6_addr *a)
 608{
 609#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 610        const __be64 *be = (const __be64 *)a;
 611
 612        return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
 613#else
 614        return (a->s6_addr32[0] | a->s6_addr32[1] |
 615                a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
 616#endif
 617}
 618
 619/*
 620 * Note that we must __force cast these to unsigned long to make sparse happy,
 621 * since all of the endian-annotated types are fixed size regardless of arch.
 622 */
 623static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
 624{
 625        return (
 626#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 627                *(unsigned long *)a |
 628#else
 629                (__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
 630#endif
 631                (__force unsigned long)(a->s6_addr32[2] ^
 632                                        cpu_to_be32(0x0000ffff))) == 0UL;
 633}
 634
 635/*
 636 * Check for a RFC 4843 ORCHID address
 637 * (Overlay Routable Cryptographic Hash Identifiers)
 638 */
 639static inline bool ipv6_addr_orchid(const struct in6_addr *a)
 640{
 641        return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
 642}
 643
 644static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
 645{
 646        return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
 647}
 648
 649static inline void ipv6_addr_set_v4mapped(const __be32 addr,
 650                                          struct in6_addr *v4mapped)
 651{
 652        ipv6_addr_set(v4mapped,
 653                        0, 0,
 654                        htonl(0x0000FFFF),
 655                        addr);
 656}
 657
 658/*
 659 * find the first different bit between two addresses
 660 * length of address must be a multiple of 32bits
 661 */
 662static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
 663{
 664        const __be32 *a1 = token1, *a2 = token2;
 665        int i;
 666
 667        addrlen >>= 2;
 668
 669        for (i = 0; i < addrlen; i++) {
 670                __be32 xb = a1[i] ^ a2[i];
 671                if (xb)
 672                        return i * 32 + 31 - __fls(ntohl(xb));
 673        }
 674
 675        /*
 676         *      we should *never* get to this point since that 
 677         *      would mean the addrs are equal
 678         *
 679         *      However, we do get to it 8) And exacly, when
 680         *      addresses are equal 8)
 681         *
 682         *      ip route add 1111::/128 via ...
 683         *      ip route add 1111::/64 via ...
 684         *      and we are here.
 685         *
 686         *      Ideally, this function should stop comparison
 687         *      at prefix length. It does not, but it is still OK,
 688         *      if returned value is greater than prefix length.
 689         *                                      --ANK (980803)
 690         */
 691        return addrlen << 5;
 692}
 693
 694#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 695static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
 696{
 697        const __be64 *a1 = token1, *a2 = token2;
 698        int i;
 699
 700        addrlen >>= 3;
 701
 702        for (i = 0; i < addrlen; i++) {
 703                __be64 xb = a1[i] ^ a2[i];
 704                if (xb)
 705                        return i * 64 + 63 - __fls(be64_to_cpu(xb));
 706        }
 707
 708        return addrlen << 6;
 709}
 710#endif
 711
 712static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
 713{
 714#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 715        if (__builtin_constant_p(addrlen) && !(addrlen & 7))
 716                return __ipv6_addr_diff64(token1, token2, addrlen);
 717#endif
 718        return __ipv6_addr_diff32(token1, token2, addrlen);
 719}
 720
 721static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
 722{
 723        return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
 724}
 725
 726__be32 ipv6_select_ident(struct net *net,
 727                         const struct in6_addr *daddr,
 728                         const struct in6_addr *saddr);
 729void ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
 730
 731int ip6_dst_hoplimit(struct dst_entry *dst);
 732
 733static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
 734                                      struct dst_entry *dst)
 735{
 736        int hlimit;
 737
 738        if (ipv6_addr_is_multicast(&fl6->daddr))
 739                hlimit = np->mcast_hops;
 740        else
 741                hlimit = np->hop_limit;
 742        if (hlimit < 0)
 743                hlimit = ip6_dst_hoplimit(dst);
 744        return hlimit;
 745}
 746
 747/* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
 748 * Equivalent to :      flow->v6addrs.src = iph->saddr;
 749 *                      flow->v6addrs.dst = iph->daddr;
 750 */
 751static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
 752                                            const struct ipv6hdr *iph)
 753{
 754        BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
 755                     offsetof(typeof(flow->addrs), v6addrs.src) +
 756                     sizeof(flow->addrs.v6addrs.src));
 757        memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs));
 758        flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 759}
 760
 761#if IS_ENABLED(CONFIG_IPV6)
 762
 763/* Sysctl settings for net ipv6.auto_flowlabels */
 764#define IP6_AUTO_FLOW_LABEL_OFF         0
 765#define IP6_AUTO_FLOW_LABEL_OPTOUT      1
 766#define IP6_AUTO_FLOW_LABEL_OPTIN       2
 767#define IP6_AUTO_FLOW_LABEL_FORCED      3
 768
 769#define IP6_AUTO_FLOW_LABEL_MAX         IP6_AUTO_FLOW_LABEL_FORCED
 770
 771#define IP6_DEFAULT_AUTO_FLOW_LABELS    IP6_AUTO_FLOW_LABEL_OPTOUT
 772
 773static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 774                                        __be32 flowlabel, bool autolabel,
 775                                        struct flowi6 *fl6)
 776{
 777        u32 hash;
 778
 779        /* @flowlabel may include more than a flow label, eg, the traffic class.
 780         * Here we want only the flow label value.
 781         */
 782        flowlabel &= IPV6_FLOWLABEL_MASK;
 783
 784        if (flowlabel ||
 785            net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
 786            (!autolabel &&
 787             net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
 788                return flowlabel;
 789
 790        hash = skb_get_hash_flowi6(skb, fl6);
 791
 792        /* Since this is being sent on the wire obfuscate hash a bit
 793         * to minimize possbility that any useful information to an
 794         * attacker is leaked. Only lower 20 bits are relevant.
 795         */
 796        rol32(hash, 16);
 797
 798        flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
 799
 800        if (net->ipv6.sysctl.flowlabel_state_ranges)
 801                flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
 802
 803        return flowlabel;
 804}
 805
 806static inline int ip6_default_np_autolabel(struct net *net)
 807{
 808        switch (net->ipv6.sysctl.auto_flowlabels) {
 809        case IP6_AUTO_FLOW_LABEL_OFF:
 810        case IP6_AUTO_FLOW_LABEL_OPTIN:
 811        default:
 812                return 0;
 813        case IP6_AUTO_FLOW_LABEL_OPTOUT:
 814        case IP6_AUTO_FLOW_LABEL_FORCED:
 815                return 1;
 816        }
 817}
 818#else
 819static inline void ip6_set_txhash(struct sock *sk) { }
 820static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 821                                        __be32 flowlabel, bool autolabel,
 822                                        struct flowi6 *fl6)
 823{
 824        return flowlabel;
 825}
 826static inline int ip6_default_np_autolabel(struct net *net)
 827{
 828        return 0;
 829}
 830#endif
 831
 832
 833/*
 834 *      Header manipulation
 835 */
 836static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
 837                                __be32 flowlabel)
 838{
 839        *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
 840}
 841
 842static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
 843{
 844        return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
 845}
 846
 847static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
 848{
 849        return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
 850}
 851
 852static inline u8 ip6_tclass(__be32 flowinfo)
 853{
 854        return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
 855}
 856
 857static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
 858{
 859        return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
 860}
 861
 862/*
 863 *      Prototypes exported by ipv6
 864 */
 865
 866/*
 867 *      rcv function (called from netdevice level)
 868 */
 869
 870int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
 871             struct packet_type *pt, struct net_device *orig_dev);
 872
 873int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
 874
 875/*
 876 *      upper-layer output functions
 877 */
 878int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
 879             __u32 mark, struct ipv6_txoptions *opt, int tclass);
 880
 881int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
 882
 883int ip6_append_data(struct sock *sk,
 884                    int getfrag(void *from, char *to, int offset, int len,
 885                                int odd, struct sk_buff *skb),
 886                    void *from, int length, int transhdrlen,
 887                    struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
 888                    struct rt6_info *rt, unsigned int flags,
 889                    const struct sockcm_cookie *sockc);
 890
 891int ip6_push_pending_frames(struct sock *sk);
 892
 893void ip6_flush_pending_frames(struct sock *sk);
 894
 895int ip6_send_skb(struct sk_buff *skb);
 896
 897struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
 898                               struct inet_cork_full *cork,
 899                               struct inet6_cork *v6_cork);
 900struct sk_buff *ip6_make_skb(struct sock *sk,
 901                             int getfrag(void *from, char *to, int offset,
 902                                         int len, int odd, struct sk_buff *skb),
 903                             void *from, int length, int transhdrlen,
 904                             struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
 905                             struct rt6_info *rt, unsigned int flags,
 906                             const struct sockcm_cookie *sockc);
 907
 908static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
 909{
 910        return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
 911                              &inet6_sk(sk)->cork);
 912}
 913
 914int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
 915                   struct flowi6 *fl6);
 916struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
 917                                      const struct in6_addr *final_dst);
 918struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 919                                         const struct in6_addr *final_dst);
 920struct dst_entry *ip6_blackhole_route(struct net *net,
 921                                      struct dst_entry *orig_dst);
 922
 923/*
 924 *      skb processing functions
 925 */
 926
 927int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
 928int ip6_forward(struct sk_buff *skb);
 929int ip6_input(struct sk_buff *skb);
 930int ip6_mc_input(struct sk_buff *skb);
 931
 932int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
 933int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
 934
 935/*
 936 *      Extension header (options) processing
 937 */
 938
 939void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
 940                          u8 *proto, struct in6_addr **daddr_p,
 941                          struct in6_addr *saddr);
 942void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
 943                         u8 *proto);
 944
 945int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
 946                     __be16 *frag_offp);
 947
 948bool ipv6_ext_hdr(u8 nexthdr);
 949
 950enum {
 951        IP6_FH_F_FRAG           = (1 << 0),
 952        IP6_FH_F_AUTH           = (1 << 1),
 953        IP6_FH_F_SKIP_RH        = (1 << 2),
 954};
 955
 956/* find specified header and get offset to it */
 957int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
 958                  unsigned short *fragoff, int *fragflg);
 959
 960int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type);
 961
 962struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
 963                                const struct ipv6_txoptions *opt,
 964                                struct in6_addr *orig);
 965
 966/*
 967 *      socket options (ipv6_sockglue.c)
 968 */
 969
 970int ipv6_setsockopt(struct sock *sk, int level, int optname,
 971                    char __user *optval, unsigned int optlen);
 972int ipv6_getsockopt(struct sock *sk, int level, int optname,
 973                    char __user *optval, int __user *optlen);
 974int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
 975                           char __user *optval, unsigned int optlen);
 976int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
 977                           char __user *optval, int __user *optlen);
 978
 979int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr,
 980                           int addr_len);
 981int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
 982int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
 983                                 int addr_len);
 984int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
 985void ip6_datagram_release_cb(struct sock *sk);
 986
 987int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
 988                    int *addr_len);
 989int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
 990                     int *addr_len);
 991void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
 992                     u32 info, u8 *payload);
 993void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
 994void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
 995
 996int inet6_release(struct socket *sock);
 997int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
 998int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
 999                  int peer);
1000int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
1001
1002int inet6_hash_connect(struct inet_timewait_death_row *death_row,
1003                              struct sock *sk);
1004
1005/*
1006 * reassembly.c
1007 */
1008extern const struct proto_ops inet6_stream_ops;
1009extern const struct proto_ops inet6_dgram_ops;
1010
1011struct group_source_req;
1012struct group_filter;
1013
1014int ip6_mc_source(int add, int omode, struct sock *sk,
1015                  struct group_source_req *pgsr);
1016int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
1017int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1018                  struct group_filter __user *optval, int __user *optlen);
1019
1020#ifdef CONFIG_PROC_FS
1021int ac6_proc_init(struct net *net);
1022void ac6_proc_exit(struct net *net);
1023int raw6_proc_init(void);
1024void raw6_proc_exit(void);
1025int tcp6_proc_init(struct net *net);
1026void tcp6_proc_exit(struct net *net);
1027int udp6_proc_init(struct net *net);
1028void udp6_proc_exit(struct net *net);
1029int udplite6_proc_init(void);
1030void udplite6_proc_exit(void);
1031int ipv6_misc_proc_init(void);
1032void ipv6_misc_proc_exit(void);
1033int snmp6_register_dev(struct inet6_dev *idev);
1034int snmp6_unregister_dev(struct inet6_dev *idev);
1035
1036#else
1037static inline int ac6_proc_init(struct net *net) { return 0; }
1038static inline void ac6_proc_exit(struct net *net) { }
1039static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1040static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1041#endif
1042
1043#ifdef CONFIG_SYSCTL
1044extern struct ctl_table ipv6_route_table_template[];
1045
1046struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1047struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1048int ipv6_sysctl_register(void);
1049void ipv6_sysctl_unregister(void);
1050#endif
1051
1052int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1053                      const struct in6_addr *addr);
1054int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1055                      const struct in6_addr *addr);
1056#endif /* _NET_IPV6_H */
1057