include/net/addrconf.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ADDRCONF_H
   3 #define _ADDRCONF_H
   4
   5 #define MAX_RTR_SOLICITATIONS           -1              /* unlimited */
   6 #define RTR_SOLICITATION_INTERVAL       (4*HZ)
   7 #define RTR_SOLICITATION_MAX_INTERVAL   (3600*HZ)       /* 1 hour */
   8
   9 #define MIN_VALID_LIFETIME              (2*3600)        /* 2 hours */
  10
  11 #define TEMP_VALID_LIFETIME             (7*86400)       /* 1 week */
  12 #define TEMP_PREFERRED_LIFETIME         (86400)         /* 24 hours */
  13 #define REGEN_MIN_ADVANCE               (2)             /* 2 seconds */
  14 #define REGEN_MAX_RETRY                 (3)
  15 #define MAX_DESYNC_FACTOR               (600)
  16
  17 #define ADDR_CHECK_FREQUENCY            (120*HZ)
  18
  19 #define IPV6_MAX_ADDRESSES              16
  20
  21 #define ADDRCONF_TIMER_FUZZ_MINUS       (HZ > 50 ? HZ / 50 : 1)
  22 #define ADDRCONF_TIMER_FUZZ             (HZ / 4)
  23 #define ADDRCONF_TIMER_FUZZ_MAX         (HZ)
  24
  25 #define ADDRCONF_NOTIFY_PRIORITY        0
  26
  27 #include <linux/in.h>
  28 #include <linux/in6.h>
  29
  30 struct prefix_info {
  31         __u8                    type;
  32         __u8                    length;
  33         __u8                    prefix_len;
  34
  35         union __packed {
  36                 __u8            flags;
  37                 struct __packed {
  38 #if defined(__BIG_ENDIAN_BITFIELD)
  39                         __u8    onlink : 1,
  40                                 autoconf : 1,
  41                                 routeraddr : 1,
  42                                 preferpd : 1,
  43                                 reserved : 4;
  44 #elif defined(__LITTLE_ENDIAN_BITFIELD)
  45                         __u8    reserved : 4,
  46                                 preferpd : 1,
  47                                 routeraddr : 1,
  48                                 autoconf : 1,
  49                                 onlink : 1;
  50 #else
  51 #error "Please fix <asm/byteorder.h>"
  52 #endif
  53                 };
  54         };
  55         __be32                  valid;
  56         __be32                  prefered;
  57         __be32                  reserved2;
  58
  59         struct in6_addr         prefix;
  60 };
  61
  62 /* rfc4861 4.6.2: IPv6 PIO is 32 bytes in size */
  63 static_assert(sizeof(struct prefix_info) == 32);
  64
  65 #include <linux/ipv6.h>
  66 #include <linux/netdevice.h>
  67 #include <net/if_inet6.h>
  68 #include <net/ipv6.h>
  69
  70 struct in6_validator_info {
  71         struct in6_addr         i6vi_addr;
  72         struct inet6_dev        *i6vi_dev;
  73         struct netlink_ext_ack  *extack;
  74 };
  75
  76 struct ifa6_config {
  77         const struct in6_addr   *pfx;
  78         unsigned int            plen;
  79
  80         u8                      ifa_proto;
  81
  82         const struct in6_addr   *peer_pfx;
  83
  84         u32                     rt_priority;
  85         u32                     ifa_flags;
  86         u32                     preferred_lft;
  87         u32                     valid_lft;
  88         u16                     scope;
  89 };
  90
  91 int addrconf_init(void);
  92 void addrconf_cleanup(void);
  93
  94 int addrconf_add_ifaddr(struct net *net, void __user *arg);
  95 int addrconf_del_ifaddr(struct net *net, void __user *arg);
  96 int addrconf_set_dstaddr(struct net *net, void __user *arg);
  97
  98 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  99                   const struct net_device *dev, int strict);
 100 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
 101                             const struct net_device *dev, bool skip_dev_check,
 102                             int strict, u32 banned_flags);
 103
 104 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
 105 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr);
 106 #endif
 107
 108 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
 109                           unsigned char nsegs);
 110
 111 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
 112                                    const unsigned int prefix_len,
 113                                    struct net_device *dev);
 114
 115 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
 116
 117 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
 118                                  struct net_device *dev);
 119
 120 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
 121                                      const struct in6_addr *addr,
 122                                      struct net_device *dev, int strict);
 123
 124 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dev,
 125                        const struct in6_addr *daddr, unsigned int srcprefs,
 126                        struct in6_addr *saddr);
 127 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
 128                     u32 banned_flags);
 129 bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
 130                           bool match_wildcard);
 131 bool inet_rcv_saddr_any(const struct sock *sk);
 132 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr);
 133 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr);
 134
 135 void addrconf_add_linklocal(struct inet6_dev *idev,
 136                             const struct in6_addr *addr, u32 flags);
 137
 138 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
 139                                  const struct prefix_info *pinfo,
 140                                  struct inet6_dev *in6_dev,
 141                                  const struct in6_addr *addr, int addr_type,
 142                                  u32 addr_flags, bool sllao, bool tokenized,
 143                                  __u32 valid_lft, u32 prefered_lft);
 144
 145 static inline void addrconf_addr_eui48_base(u8 *eui, const char *const addr)
 146 {
 147         memcpy(eui, addr, 3);
 148         eui[3] = 0xFF;
 149         eui[4] = 0xFE;
 150         memcpy(eui + 5, addr + 3, 3);
 151 }
 152
 153 static inline void addrconf_addr_eui48(u8 *eui, const char *const addr)
 154 {
 155         addrconf_addr_eui48_base(eui, addr);
 156         eui[0] ^= 2;
 157 }
 158
 159 static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
 160 {
 161         if (dev->addr_len != ETH_ALEN)
 162                 return -1;
 163
 164         /*
 165          * The zSeries OSA network cards can be shared among various
 166          * OS instances, but the OSA cards have only one MAC address.
 167          * This leads to duplicate address conflicts in conjunction
 168          * with IPv6 if more than one instance uses the same card.
 169          *
 170          * The driver for these cards can deliver a unique 16-bit
 171          * identifier for each instance sharing the same card.  It is
 172          * placed instead of 0xFFFE in the interface identifier.  The
 173          * "u" bit of the interface identifier is not inverted in this
 174          * case.  Hence the resulting interface identifier has local
 175          * scope according to RFC2373.
 176          */
 177
 178         addrconf_addr_eui48_base(eui, dev->dev_addr);
 179
 180         if (dev->dev_id) {
 181                 eui[3] = (dev->dev_id >> 8) & 0xFF;
 182                 eui[4] = dev->dev_id & 0xFF;
 183         } else {
 184                 eui[0] ^= 2;
 185         }
 186
 187         return 0;
 188 }
 189
 190 #define INFINITY_LIFE_TIME 0xFFFFFFFF
 191
 192 static inline unsigned long addrconf_timeout_fixup(u32 timeout,
 193                                                    unsigned int unit)
 194 {
 195         if (timeout == INFINITY_LIFE_TIME)
 196                 return ~0UL;
 197
 198         /*
 199          * Avoid arithmetic overflow.
 200          * Assuming unit is constant and non-zero, this "if" statement
 201          * will go away on 64bit archs.
 202          */
 203         if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
 204                 return LONG_MAX / unit;
 205
 206         return timeout;
 207 }
 208
 209 static inline int addrconf_finite_timeout(unsigned long timeout)
 210 {
 211         return ~timeout;
 212 }
 213
 214 /*
 215  *      IPv6 Address Label subsystem (addrlabel.c)
 216  */
 217 int ipv6_addr_label_init(void);
 218 void ipv6_addr_label_cleanup(void);
 219 int ipv6_addr_label_rtnl_register(void);
 220 u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr,
 221                     int type, int ifindex);
 222
 223 /*
 224  *      multicast prototypes (mcast.c)
 225  */
 226 static inline bool ipv6_mc_may_pull(struct sk_buff *skb,
 227                                     unsigned int len)
 228 {
 229         if (skb_transport_offset(skb) + ipv6_transport_len(skb) < len)
 230                 return false;
 231
 232         return pskb_may_pull(skb, len);
 233 }
 234
 235 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
 236                       const struct in6_addr *addr);
 237 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
 238                       const struct in6_addr *addr);
 239 void __ipv6_sock_mc_close(struct sock *sk);
 240 void ipv6_sock_mc_close(struct sock *sk);
 241 bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
 242                     const struct in6_addr *src_addr);
 243
 244 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
 245 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
 246 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
 247 void ipv6_mc_up(struct inet6_dev *idev);
 248 void ipv6_mc_down(struct inet6_dev *idev);
 249 void ipv6_mc_unmap(struct inet6_dev *idev);
 250 void ipv6_mc_remap(struct inet6_dev *idev);
 251 void ipv6_mc_init_dev(struct inet6_dev *idev);
 252 void ipv6_mc_destroy_dev(struct inet6_dev *idev);
 253 int ipv6_mc_check_mld(struct sk_buff *skb);
 254 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp);
 255
 256 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
 257                          const struct in6_addr *src_addr);
 258
 259 void ipv6_mc_dad_complete(struct inet6_dev *idev);
 260
 261 /*
 262  * identify MLD packets for MLD filter exceptions
 263  */
 264 static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
 265 {
 266         struct icmp6hdr *hdr;
 267
 268         if (nexthdr != IPPROTO_ICMPV6 ||
 269             !pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
 270                 return false;
 271
 272         hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
 273
 274         switch (hdr->icmp6_type) {
 275         case ICMPV6_MGM_QUERY:
 276         case ICMPV6_MGM_REPORT:
 277         case ICMPV6_MGM_REDUCTION:
 278         case ICMPV6_MLD2_REPORT:
 279                 return true;
 280         default:
 281                 break;
 282         }
 283         return false;
 284 }
 285
 286 void addrconf_prefix_rcv(struct net_device *dev,
 287                          u8 *opt, int len, bool sllao);
 288
 289 /*
 290  *      anycast prototypes (anycast.c)
 291  */
 292 int ipv6_sock_ac_join(struct sock *sk, int ifindex,
 293                       const struct in6_addr *addr);
 294 int ipv6_sock_ac_drop(struct sock *sk, int ifindex,
 295                       const struct in6_addr *addr);
 296 void __ipv6_sock_ac_close(struct sock *sk);
 297 void ipv6_sock_ac_close(struct sock *sk);
 298
 299 int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr);
 300 int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
 301 void ipv6_ac_destroy_dev(struct inet6_dev *idev);
 302 bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
 303                          const struct in6_addr *addr);
 304 bool ipv6_chk_acast_addr_src(struct net *net, struct net_device *dev,
 305                              const struct in6_addr *addr);
 306 int ipv6_anycast_init(void);
 307 void ipv6_anycast_cleanup(void);
 308
 309 /* Device notifier */
 310 int register_inet6addr_notifier(struct notifier_block *nb);
 311 int unregister_inet6addr_notifier(struct notifier_block *nb);
 312 int inet6addr_notifier_call_chain(unsigned long val, void *v);
 313
 314 int register_inet6addr_validator_notifier(struct notifier_block *nb);
 315 int unregister_inet6addr_validator_notifier(struct notifier_block *nb);
 316 int inet6addr_validator_notifier_call_chain(unsigned long val, void *v);
 317
 318 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
 319                                   int ifindex, struct ipv6_devconf *devconf);
 320
 321 /**
 322  * __in6_dev_get - get inet6_dev pointer from netdevice
 323  * @dev: network device
 324  *
 325  * Caller must hold rcu_read_lock or RTNL, because this function
 326  * does not take a reference on the inet6_dev.
 327  */
 328 static inline struct inet6_dev *__in6_dev_get(const struct net_device *dev)
 329 {
 330         return rcu_dereference_rtnl(dev->ip6_ptr);
 331 }
 332
 333 /**
 334  * __in6_dev_stats_get - get inet6_dev pointer for stats
 335  * @dev: network device
 336  * @skb: skb for original incoming interface if needed
 337  *
 338  * Caller must hold rcu_read_lock or RTNL, because this function
 339  * does not take a reference on the inet6_dev.
 340  */
 341 static inline struct inet6_dev *__in6_dev_stats_get(const struct net_device *dev,
 342                                                     const struct sk_buff *skb)
 343 {
 344         if (netif_is_l3_master(dev))
 345                 dev = dev_get_by_index_rcu(dev_net(dev), inet6_iif(skb));
 346         return __in6_dev_get(dev);
 347 }
 348
 349 /**
 350  * __in6_dev_get_safely - get inet6_dev pointer from netdevice
 351  * @dev: network device
 352  *
 353  * This is a safer version of __in6_dev_get
 354  */
 355 static inline struct inet6_dev *__in6_dev_get_safely(const struct net_device *dev)
 356 {
 357         if (likely(dev))
 358                 return rcu_dereference_rtnl(dev->ip6_ptr);
 359         else
 360                 return NULL;
 361 }
 362
 363 /**
 364  * in6_dev_get - get inet6_dev pointer from netdevice
 365  * @dev: network device
 366  *
 367  * This version can be used in any context, and takes a reference
 368  * on the inet6_dev. Callers must use in6_dev_put() later to
 369  * release this reference.
 370  */
 371 static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
 372 {
 373         struct inet6_dev *idev;
 374
 375         rcu_read_lock();
 376         idev = rcu_dereference(dev->ip6_ptr);
 377         if (idev)
 378                 refcount_inc(&idev->refcnt);
 379         rcu_read_unlock();
 380         return idev;
 381 }
 382
 383 static inline struct neigh_parms *__in6_dev_nd_parms_get_rcu(const struct net_device *dev)
 384 {
 385         struct inet6_dev *idev = __in6_dev_get(dev);
 386
 387         return idev ? idev->nd_parms : NULL;
 388 }
 389
 390 void in6_dev_finish_destroy(struct inet6_dev *idev);
 391
 392 static inline void in6_dev_put(struct inet6_dev *idev)
 393 {
 394         if (refcount_dec_and_test(&idev->refcnt))
 395                 in6_dev_finish_destroy(idev);
 396 }
 397
 398 static inline void in6_dev_put_clear(struct inet6_dev **pidev)
 399 {
 400         struct inet6_dev *idev = *pidev;
 401
 402         if (idev) {
 403                 in6_dev_put(idev);
 404                 *pidev = NULL;
 405         }
 406 }
 407
 408 static inline void __in6_dev_put(struct inet6_dev *idev)
 409 {
 410         refcount_dec(&idev->refcnt);
 411 }
 412
 413 static inline void in6_dev_hold(struct inet6_dev *idev)
 414 {
 415         refcount_inc(&idev->refcnt);
 416 }
 417
 418 /* called with rcu_read_lock held */
 419 static inline bool ip6_ignore_linkdown(const struct net_device *dev)
 420 {
 421         const struct inet6_dev *idev = __in6_dev_get(dev);
 422
 423         if (unlikely(!idev))
 424                 return true;
 425
 426         return !!READ_ONCE(idev->cnf.ignore_routes_with_linkdown);
 427 }
 428
 429 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
 430
 431 static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
 432 {
 433         if (refcount_dec_and_test(&ifp->refcnt))
 434                 inet6_ifa_finish_destroy(ifp);
 435 }
 436
 437 static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
 438 {
 439         refcount_dec(&ifp->refcnt);
 440 }
 441
 442 static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
 443 {
 444         refcount_inc(&ifp->refcnt);
 445 }
 446
 447 static inline bool in6_ifa_hold_safe(struct inet6_ifaddr *ifp)
 448 {
 449         return refcount_inc_not_zero(&ifp->refcnt);
 450 }
 451
 452 /*
 453  *      compute link-local solicited-node multicast address
 454  */
 455
 456 static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
 457                                              struct in6_addr *solicited)
 458 {
 459         ipv6_addr_set(solicited,
 460                       htonl(0xFF020000), 0,
 461                       htonl(0x1),
 462                       htonl(0xFF000000) | addr->s6_addr32[3]);
 463 }
 464
 465 static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
 466 {
 467 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 468         __be64 *p = (__force __be64 *)addr;
 469         return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
 470 #else
 471         return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
 472                 addr->s6_addr32[1] | addr->s6_addr32[2] |
 473                 (addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
 474 #endif
 475 }
 476
 477 static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
 478 {
 479 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 480         __be64 *p = (__force __be64 *)addr;
 481         return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 0UL;
 482 #else
 483         return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
 484                 addr->s6_addr32[1] | addr->s6_addr32[2] |
 485                 (addr->s6_addr32[3] ^ htonl(0x00000002))) == 0;
 486 #endif
 487 }
 488
 489 static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
 490 {
 491         return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
 492 }
 493
 494 static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
 495 {
 496 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 497         __be64 *p = (__force __be64 *)addr;
 498         return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
 499                 ((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
 500                  cpu_to_be64(0xffffffffff000000UL))) == 0UL;
 501 #else
 502         return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
 503                 addr->s6_addr32[1] |
 504                 (addr->s6_addr32[2] ^ htonl(0x00000001)) |
 505                 (addr->s6_addr[12] ^ 0xff)) == 0;
 506 #endif
 507 }
 508
 509 static inline bool ipv6_addr_is_all_snoopers(const struct in6_addr *addr)
 510 {
 511 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 512         __be64 *p = (__force __be64 *)addr;
 513
 514         return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
 515                 (p[1] ^ cpu_to_be64(0x6a))) == 0UL;
 516 #else
 517         return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
 518                 addr->s6_addr32[1] | addr->s6_addr32[2] |
 519                 (addr->s6_addr32[3] ^ htonl(0x0000006a))) == 0;
 520 #endif
 521 }
 522
 523 #ifdef CONFIG_PROC_FS
 524 int if6_proc_init(void);
 525 void if6_proc_exit(void);
 526 #endif
 527
 528 #endif