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 <net/if_inet6.h> 19 #include <net/ndisc.h> 20 #include <net/flow.h> 21 #include <net/snmp.h> 22 23 #define SIN6_LEN_RFC2133 24 24 25 #define IPV6_MAXPLEN 65535 26 27 /* 28 * NextHeader field of IPv6 header 29 */ 30 31 #define NEXTHDR_HOP 0 /* Hop-by-hop option header. */ 32 #define NEXTHDR_TCP 6 /* TCP segment. */ 33 #define NEXTHDR_UDP 17 /* UDP message. */ 34 #define NEXTHDR_IPV6 41 /* IPv6 in IPv6 */ 35 #define NEXTHDR_ROUTING 43 /* Routing header. */ 36 #define NEXTHDR_FRAGMENT 44 /* Fragmentation/reassembly header. */ 37 #define NEXTHDR_ESP 50 /* Encapsulating security payload. */ 38 #define NEXTHDR_AUTH 51 /* Authentication header. */ 39 #define NEXTHDR_ICMP 58 /* ICMP for IPv6. */ 40 #define NEXTHDR_NONE 59 /* No next header */ 41 #define NEXTHDR_DEST 60 /* Destination options header. */ 42 #define NEXTHDR_MOBILITY 135 /* Mobility header. */ 43 44 #define NEXTHDR_MAX 255 45 46 47 48 #define IPV6_DEFAULT_HOPLIMIT 64 49 #define IPV6_DEFAULT_MCASTHOPS 1 50 51 /* 52 * Addr type 53 * 54 * type - unicast | multicast 55 * scope - local | site | global 56 * v4 - compat 57 * v4mapped 58 * any 59 * loopback 60 */ 61 62 #define IPV6_ADDR_ANY 0x0000U 63 64 #define IPV6_ADDR_UNICAST 0x0001U 65 #define IPV6_ADDR_MULTICAST 0x0002U 66 67 #define IPV6_ADDR_LOOPBACK 0x0010U 68 #define IPV6_ADDR_LINKLOCAL 0x0020U 69 #define IPV6_ADDR_SITELOCAL 0x0040U 70 71 #define IPV6_ADDR_COMPATv4 0x0080U 72 73 #define IPV6_ADDR_SCOPE_MASK 0x00f0U 74 75 #define IPV6_ADDR_MAPPED 0x1000U 76 #define IPV6_ADDR_RESERVED 0x2000U /* reserved address space */ 77 78 /* 79 * Addr scopes 80 */ 81 #ifdef __KERNEL__ 82 #define IPV6_ADDR_MC_SCOPE(a) \ 83 ((a)->s6_addr[1] & 0x0f) /* nonstandard */ 84 #define __IPV6_ADDR_SCOPE_INVALID -1 85 #endif 86 #define IPV6_ADDR_SCOPE_NODELOCAL 0x01 87 #define IPV6_ADDR_SCOPE_LINKLOCAL 0x02 88 #define IPV6_ADDR_SCOPE_SITELOCAL 0x05 89 #define IPV6_ADDR_SCOPE_ORGLOCAL 0x08 90 #define IPV6_ADDR_SCOPE_GLOBAL 0x0e 91 92 /* 93 * fragmentation header 94 */ 95 96 struct frag_hdr { 97 __u8 nexthdr; 98 __u8 reserved; 99 __be16 frag_off; 100 __be32 identification; 101 }; 102 103 #define IP6_MF 0x0001 104 105 #ifdef __KERNEL__ 106 107 #include <net/sock.h> 108 109 /* sysctls */ 110 extern int sysctl_mld_max_msf; 111 extern struct ctl_path net_ipv6_ctl_path[]; 112 113 #define _DEVINC(net, statname, modifier, idev, field) \ 114 ({ \ 115 struct inet6_dev *_idev = (idev); \ 116 if (likely(_idev != NULL)) \ 117 SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \ 118 SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\ 119 }) 120 121 #define _DEVADD(net, statname, modifier, idev, field, val) \ 122 ({ \ 123 struct inet6_dev *_idev = (idev); \ 124 if (likely(_idev != NULL)) \ 125 SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \ 126 SNMP_ADD_STATS##modifier((net)->mib.statname##_statistics, (field), (val));\ 127 }) 128 129 #define _DEVUPD(net, statname, modifier, idev, field, val) \ 130 ({ \ 131 struct inet6_dev *_idev = (idev); \ 132 if (likely(_idev != NULL)) \ 133 SNMP_UPD_PO_STATS##modifier((_idev)->stats.statname, field, (val)); \ 134 SNMP_UPD_PO_STATS##modifier((net)->mib.statname##_statistics, field, (val));\ 135 }) 136 137 /* MIBs */ 138 139 #define IP6_INC_STATS(net, idev,field) \ 140 _DEVINC(net, ipv6, , idev, field) 141 #define IP6_INC_STATS_BH(net, idev,field) \ 142 _DEVINC(net, ipv6, _BH, idev, field) 143 #define IP6_ADD_STATS(net, idev,field,val) \ 144 _DEVADD(net, ipv6, , idev, field, val) 145 #define IP6_ADD_STATS_BH(net, idev,field,val) \ 146 _DEVADD(net, ipv6, _BH, idev, field, val) 147 #define IP6_UPD_PO_STATS(net, idev,field,val) \ 148 _DEVUPD(net, ipv6, , idev, field, val) 149 #define IP6_UPD_PO_STATS_BH(net, idev,field,val) \ 150 _DEVUPD(net, ipv6, _BH, idev, field, val) 151 #define ICMP6_INC_STATS(net, idev, field) \ 152 _DEVINC(net, icmpv6, , idev, field) 153 #define ICMP6_INC_STATS_BH(net, idev, field) \ 154 _DEVINC(net, icmpv6, _BH, idev, field) 155 156 #define ICMP6MSGOUT_INC_STATS(net, idev, field) \ 157 _DEVINC(net, icmpv6msg, , idev, field +256) 158 #define ICMP6MSGOUT_INC_STATS_BH(net, idev, field) \ 159 _DEVINC(net, icmpv6msg, _BH, idev, field +256) 160 #define ICMP6MSGIN_INC_STATS_BH(net, idev, field) \ 161 _DEVINC(net, icmpv6msg, _BH, idev, field) 162 163 struct ip6_ra_chain 164 { 165 struct ip6_ra_chain *next; 166 struct sock *sk; 167 int sel; 168 void (*destructor)(struct sock *); 169 }; 170 171 extern struct ip6_ra_chain *ip6_ra_chain; 172 extern rwlock_t ip6_ra_lock; 173 174 /* 175 This structure is prepared by protocol, when parsing 176 ancillary data and passed to IPv6. 177 */ 178 179 struct ipv6_txoptions 180 { 181 /* Length of this structure */ 182 int tot_len; 183 184 /* length of extension headers */ 185 186 __u16 opt_flen; /* after fragment hdr */ 187 __u16 opt_nflen; /* before fragment hdr */ 188 189 struct ipv6_opt_hdr *hopopt; 190 struct ipv6_opt_hdr *dst0opt; 191 struct ipv6_rt_hdr *srcrt; /* Routing Header */ 192 struct ipv6_opt_hdr *dst1opt; 193 194 /* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */ 195 }; 196 197 struct ip6_flowlabel 198 { 199 struct ip6_flowlabel *next; 200 __be32 label; 201 atomic_t users; 202 struct in6_addr dst; 203 struct ipv6_txoptions *opt; 204 unsigned long linger; 205 u8 share; 206 u32 owner; 207 unsigned long lastuse; 208 unsigned long expires; 209 struct net *fl_net; 210 }; 211 212 #define IPV6_FLOWINFO_MASK cpu_to_be32(0x0FFFFFFF) 213 #define IPV6_FLOWLABEL_MASK cpu_to_be32(0x000FFFFF) 214 215 struct ipv6_fl_socklist 216 { 217 struct ipv6_fl_socklist *next; 218 struct ip6_flowlabel *fl; 219 }; 220 221 extern struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label); 222 extern struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space, 223 struct ip6_flowlabel * fl, 224 struct ipv6_txoptions * fopt); 225 extern void fl6_free_socklist(struct sock *sk); 226 extern int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen); 227 extern int ip6_flowlabel_init(void); 228 extern void ip6_flowlabel_cleanup(void); 229 230 static inline void fl6_sock_release(struct ip6_flowlabel *fl) 231 { 232 if (fl) 233 atomic_dec(&fl->users); 234 } 235 236 extern int ip6_ra_control(struct sock *sk, int sel); 237 238 extern int ipv6_parse_hopopts(struct sk_buff *skb); 239 240 extern struct ipv6_txoptions * ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt); 241 extern struct ipv6_txoptions * ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, 242 int newtype, 243 struct ipv6_opt_hdr __user *newopt, 244 int newoptlen); 245 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, 246 struct ipv6_txoptions *opt); 247 248 extern int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb); 249 250 int ip6_frag_nqueues(struct net *net); 251 int ip6_frag_mem(struct net *net); 252 253 #define IPV6_FRAG_TIMEOUT (60*HZ) /* 60 seconds */ 254 255 extern int __ipv6_addr_type(const struct in6_addr *addr); 256 static inline int ipv6_addr_type(const struct in6_addr *addr) 257 { 258 return __ipv6_addr_type(addr) & 0xffff; 259 } 260 261 static inline int ipv6_addr_scope(const struct in6_addr *addr) 262 { 263 return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK; 264 } 265 266 static inline int __ipv6_addr_src_scope(int type) 267 { 268 return (type == IPV6_ADDR_ANY ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16)); 269 } 270 271 static inline int ipv6_addr_src_scope(const struct in6_addr *addr) 272 { 273 return __ipv6_addr_src_scope(__ipv6_addr_type(addr)); 274 } 275 276 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2) 277 { 278 return memcmp(a1, a2, sizeof(struct in6_addr)); 279 } 280 281 static inline int 282 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m, 283 const struct in6_addr *a2) 284 { 285 return (!!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) | 286 ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) | 287 ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) | 288 ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]))); 289 } 290 291 static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2) 292 { 293 memcpy(a1, a2, sizeof(struct in6_addr)); 294 } 295 296 static inline void ipv6_addr_prefix(struct in6_addr *pfx, 297 const struct in6_addr *addr, 298 int plen) 299 { 300 /* caller must guarantee 0 <= plen <= 128 */ 301 int o = plen >> 3, 302 b = plen & 0x7; 303 304 memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr)); 305 memcpy(pfx->s6_addr, addr, o); 306 if (b != 0) 307 pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b); 308 } 309 310 static inline void ipv6_addr_set(struct in6_addr *addr, 311 __be32 w1, __be32 w2, 312 __be32 w3, __be32 w4) 313 { 314 addr->s6_addr32[0] = w1; 315 addr->s6_addr32[1] = w2; 316 addr->s6_addr32[2] = w3; 317 addr->s6_addr32[3] = w4; 318 } 319 320 static inline int ipv6_addr_equal(const struct in6_addr *a1, 321 const struct in6_addr *a2) 322 { 323 return (((a1->s6_addr32[0] ^ a2->s6_addr32[0]) | 324 (a1->s6_addr32[1] ^ a2->s6_addr32[1]) | 325 (a1->s6_addr32[2] ^ a2->s6_addr32[2]) | 326 (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0); 327 } 328 329 static inline int __ipv6_prefix_equal(const __be32 *a1, const __be32 *a2, 330 unsigned int prefixlen) 331 { 332 unsigned pdw, pbi; 333 334 /* check complete u32 in prefix */ 335 pdw = prefixlen >> 5; 336 if (pdw && memcmp(a1, a2, pdw << 2)) 337 return 0; 338 339 /* check incomplete u32 in prefix */ 340 pbi = prefixlen & 0x1f; 341 if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi)))) 342 return 0; 343 344 return 1; 345 } 346 347 static inline int ipv6_prefix_equal(const struct in6_addr *a1, 348 const struct in6_addr *a2, 349 unsigned int prefixlen) 350 { 351 return __ipv6_prefix_equal(a1->s6_addr32, a2->s6_addr32, 352 prefixlen); 353 } 354 355 struct inet_frag_queue; 356 357 struct ip6_create_arg { 358 __be32 id; 359 struct in6_addr *src; 360 struct in6_addr *dst; 361 }; 362 363 void ip6_frag_init(struct inet_frag_queue *q, void *a); 364 int ip6_frag_match(struct inet_frag_queue *q, void *a); 365 366 static inline int ipv6_addr_any(const struct in6_addr *a) 367 { 368 return ((a->s6_addr32[0] | a->s6_addr32[1] | 369 a->s6_addr32[2] | a->s6_addr32[3] ) == 0); 370 } 371 372 static inline int ipv6_addr_loopback(const struct in6_addr *a) 373 { 374 return ((a->s6_addr32[0] | a->s6_addr32[1] | 375 a->s6_addr32[2] | (a->s6_addr32[3] ^ htonl(1))) == 0); 376 } 377 378 static inline int ipv6_addr_v4mapped(const struct in6_addr *a) 379 { 380 return ((a->s6_addr32[0] | a->s6_addr32[1] | 381 (a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0); 382 } 383 384 /* 385 * Check for a RFC 4843 ORCHID address 386 * (Overlay Routable Cryptographic Hash Identifiers) 387 */ 388 static inline int ipv6_addr_orchid(const struct in6_addr *a) 389 { 390 return ((a->s6_addr32[0] & htonl(0xfffffff0)) 391 == htonl(0x20010010)); 392 } 393 394 static inline void ipv6_addr_set_v4mapped(const __be32 addr, 395 struct in6_addr *v4mapped) 396 { 397 ipv6_addr_set(v4mapped, 398 0, 0, 399 htonl(0x0000FFFF), 400 addr); 401 } 402 403 /* 404 * find the first different bit between two addresses 405 * length of address must be a multiple of 32bits 406 */ 407 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen) 408 { 409 const __be32 *a1 = token1, *a2 = token2; 410 int i; 411 412 addrlen >>= 2; 413 414 for (i = 0; i < addrlen; i++) { 415 __be32 xb = a1[i] ^ a2[i]; 416 if (xb) 417 return i * 32 + 32 - fls(ntohl(xb)); 418 } 419 420 /* 421 * we should *never* get to this point since that 422 * would mean the addrs are equal 423 * 424 * However, we do get to it 8) And exacly, when 425 * addresses are equal 8) 426 * 427 * ip route add 1111::/128 via ... 428 * ip route add 1111::/64 via ... 429 * and we are here. 430 * 431 * Ideally, this function should stop comparison 432 * at prefix length. It does not, but it is still OK, 433 * if returned value is greater than prefix length. 434 * --ANK (980803) 435 */ 436 return (addrlen << 5); 437 } 438 439 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2) 440 { 441 return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr)); 442 } 443 444 static __inline__ void ipv6_select_ident(struct frag_hdr *fhdr) 445 { 446 static u32 ipv6_fragmentation_id = 1; 447 static DEFINE_SPINLOCK(ip6_id_lock); 448 449 spin_lock_bh(&ip6_id_lock); 450 fhdr->identification = htonl(ipv6_fragmentation_id); 451 if (++ipv6_fragmentation_id == 0) 452 ipv6_fragmentation_id = 1; 453 spin_unlock_bh(&ip6_id_lock); 454 } 455 456 /* 457 * Prototypes exported by ipv6 458 */ 459 460 /* 461 * rcv function (called from netdevice level) 462 */ 463 464 extern int ipv6_rcv(struct sk_buff *skb, 465 struct net_device *dev, 466 struct packet_type *pt, 467 struct net_device *orig_dev); 468 469 extern int ip6_rcv_finish(struct sk_buff *skb); 470 471 /* 472 * upper-layer output functions 473 */ 474 extern int ip6_xmit(struct sock *sk, 475 struct sk_buff *skb, 476 struct flowi *fl, 477 struct ipv6_txoptions *opt, 478 int ipfragok); 479 480 extern int ip6_nd_hdr(struct sock *sk, 481 struct sk_buff *skb, 482 struct net_device *dev, 483 const struct in6_addr *saddr, 484 const struct in6_addr *daddr, 485 int proto, int len); 486 487 extern int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr); 488 489 extern int ip6_append_data(struct sock *sk, 490 int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), 491 void *from, 492 int length, 493 int transhdrlen, 494 int hlimit, 495 int tclass, 496 struct ipv6_txoptions *opt, 497 struct flowi *fl, 498 struct rt6_info *rt, 499 unsigned int flags); 500 501 extern int ip6_push_pending_frames(struct sock *sk); 502 503 extern void ip6_flush_pending_frames(struct sock *sk); 504 505 extern int ip6_dst_lookup(struct sock *sk, 506 struct dst_entry **dst, 507 struct flowi *fl); 508 extern int ip6_dst_blackhole(struct sock *sk, 509 struct dst_entry **dst, 510 struct flowi *fl); 511 extern int ip6_sk_dst_lookup(struct sock *sk, 512 struct dst_entry **dst, 513 struct flowi *fl); 514 515 /* 516 * skb processing functions 517 */ 518 519 extern int ip6_output(struct sk_buff *skb); 520 extern int ip6_forward(struct sk_buff *skb); 521 extern int ip6_input(struct sk_buff *skb); 522 extern int ip6_mc_input(struct sk_buff *skb); 523 524 extern int __ip6_local_out(struct sk_buff *skb); 525 extern int ip6_local_out(struct sk_buff *skb); 526 527 /* 528 * Extension header (options) processing 529 */ 530 531 extern void ipv6_push_nfrag_opts(struct sk_buff *skb, 532 struct ipv6_txoptions *opt, 533 u8 *proto, 534 struct in6_addr **daddr_p); 535 extern void ipv6_push_frag_opts(struct sk_buff *skb, 536 struct ipv6_txoptions *opt, 537 u8 *proto); 538 539 extern int ipv6_skip_exthdr(const struct sk_buff *, int start, 540 u8 *nexthdrp); 541 542 extern int ipv6_ext_hdr(u8 nexthdr); 543 544 extern int ipv6_find_tlv(struct sk_buff *skb, int offset, int type); 545 546 /* 547 * socket options (ipv6_sockglue.c) 548 */ 549 550 extern int ipv6_setsockopt(struct sock *sk, int level, 551 int optname, 552 char __user *optval, 553 int optlen); 554 extern int ipv6_getsockopt(struct sock *sk, int level, 555 int optname, 556 char __user *optval, 557 int __user *optlen); 558 extern int compat_ipv6_setsockopt(struct sock *sk, 559 int level, 560 int optname, 561 char __user *optval, 562 int optlen); 563 extern int compat_ipv6_getsockopt(struct sock *sk, 564 int level, 565 int optname, 566 char __user *optval, 567 int __user *optlen); 568 569 extern int ip6_datagram_connect(struct sock *sk, 570 struct sockaddr *addr, int addr_len); 571 572 extern int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len); 573 extern void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 574 u32 info, u8 *payload); 575 extern void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info); 576 577 extern int inet6_release(struct socket *sock); 578 extern int inet6_bind(struct socket *sock, struct sockaddr *uaddr, 579 int addr_len); 580 extern int inet6_getname(struct socket *sock, struct sockaddr *uaddr, 581 int *uaddr_len, int peer); 582 extern int inet6_ioctl(struct socket *sock, unsigned int cmd, 583 unsigned long arg); 584 585 extern int inet6_hash_connect(struct inet_timewait_death_row *death_row, 586 struct sock *sk); 587 588 /* 589 * reassembly.c 590 */ 591 extern const struct proto_ops inet6_stream_ops; 592 extern const struct proto_ops inet6_dgram_ops; 593 594 struct group_source_req; 595 struct group_filter; 596 597 extern int ip6_mc_source(int add, int omode, struct sock *sk, 598 struct group_source_req *pgsr); 599 extern int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf); 600 extern int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, 601 struct group_filter __user *optval, 602 int __user *optlen); 603 extern unsigned int inet6_hash_frag(__be32 id, const struct in6_addr *saddr, 604 const struct in6_addr *daddr, u32 rnd); 605 606 #ifdef CONFIG_PROC_FS 607 extern int ac6_proc_init(struct net *net); 608 extern void ac6_proc_exit(struct net *net); 609 extern int raw6_proc_init(void); 610 extern void raw6_proc_exit(void); 611 extern int tcp6_proc_init(struct net *net); 612 extern void tcp6_proc_exit(struct net *net); 613 extern int udp6_proc_init(struct net *net); 614 extern void udp6_proc_exit(struct net *net); 615 extern int udplite6_proc_init(void); 616 extern void udplite6_proc_exit(void); 617 extern int ipv6_misc_proc_init(void); 618 extern void ipv6_misc_proc_exit(void); 619 extern int snmp6_register_dev(struct inet6_dev *idev); 620 extern int snmp6_unregister_dev(struct inet6_dev *idev); 621 622 #else 623 static inline int ac6_proc_init(struct net *net) { return 0; } 624 static inline void ac6_proc_exit(struct net *net) { } 625 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; } 626 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; } 627 #endif 628 629 #ifdef CONFIG_SYSCTL 630 extern ctl_table ipv6_route_table_template[]; 631 extern ctl_table ipv6_icmp_table_template[]; 632 633 extern struct ctl_table *ipv6_icmp_sysctl_init(struct net *net); 634 extern struct ctl_table *ipv6_route_sysctl_init(struct net *net); 635 extern int ipv6_sysctl_register(void); 636 extern void ipv6_sysctl_unregister(void); 637 extern int ipv6_static_sysctl_register(void); 638 extern void ipv6_static_sysctl_unregister(void); 639 #endif 640 641 #endif /* __KERNEL__ */ 642 #endif /* _NET_IPV6_H */ 643