include/net/ip_fib.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   4  *              operating system.  INET  is implemented using the  BSD Socket
   5  *              interface as the means of communication with the user level.
   6  *
   7  *              Definitions for the Forwarding Information Base.
   8  *
   9  * Authors:     A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  */
  11
  12 #ifndef _NET_IP_FIB_H
  13 #define _NET_IP_FIB_H
  14
  15 #include <net/flow.h>
  16 #include <linux/seq_file.h>
  17 #include <linux/rcupdate.h>
  18 #include <net/fib_notifier.h>
  19 #include <net/fib_rules.h>
  20 #include <net/inet_dscp.h>
  21 #include <net/inetpeer.h>
  22 #include <linux/percpu.h>
  23 #include <linux/notifier.h>
  24 #include <linux/refcount.h>
  25 #include <linux/ip.h>
  26 #include <linux/in_route.h>
  27
  28 struct fib_config {
  29         u8                      fc_dst_len;
  30         dscp_t                  fc_dscp;
  31         u8                      fc_protocol;
  32         u8                      fc_scope;
  33         u8                      fc_type;
  34         u8                      fc_gw_family;
  35         /* 2 bytes unused */
  36         u32                     fc_table;
  37         __be32                  fc_dst;
  38         union {
  39                 __be32          fc_gw4;
  40                 struct in6_addr fc_gw6;
  41         };
  42         int                     fc_oif;
  43         u32                     fc_flags;
  44         u32                     fc_priority;
  45         __be32                  fc_prefsrc;
  46         u32                     fc_nh_id;
  47         struct nlattr           *fc_mx;
  48         struct rtnexthop        *fc_mp;
  49         int                     fc_mx_len;
  50         int                     fc_mp_len;
  51         u32                     fc_flow;
  52         u32                     fc_nlflags;
  53         struct nl_info          fc_nlinfo;
  54         struct nlattr           *fc_encap;
  55         u16                     fc_encap_type;
  56 };
  57
  58 struct fib_info;
  59 struct rtable;
  60
  61 struct fib_nh_exception {
  62         struct fib_nh_exception __rcu   *fnhe_next;
  63         int                             fnhe_genid;
  64         __be32                          fnhe_daddr;
  65         u32                             fnhe_pmtu;
  66         bool                            fnhe_mtu_locked;
  67         __be32                          fnhe_gw;
  68         unsigned long                   fnhe_expires;
  69         struct rtable __rcu             *fnhe_rth_input;
  70         struct rtable __rcu             *fnhe_rth_output;
  71         unsigned long                   fnhe_stamp;
  72         struct rcu_head                 rcu;
  73 };
  74
  75 struct fnhe_hash_bucket {
  76         struct fib_nh_exception __rcu   *chain;
  77 };
  78
  79 #define FNHE_HASH_SHIFT         11
  80 #define FNHE_HASH_SIZE          (1 << FNHE_HASH_SHIFT)
  81 #define FNHE_RECLAIM_DEPTH      5
  82
  83 struct fib_nh_common {
  84         struct net_device       *nhc_dev;
  85         netdevice_tracker       nhc_dev_tracker;
  86         int                     nhc_oif;
  87         unsigned char           nhc_scope;
  88         u8                      nhc_family;
  89         u8                      nhc_gw_family;
  90         unsigned char           nhc_flags;
  91         struct lwtunnel_state   *nhc_lwtstate;
  92
  93         union {
  94                 __be32          ipv4;
  95                 struct in6_addr ipv6;
  96         } nhc_gw;
  97
  98         int                     nhc_weight;
  99         atomic_t                nhc_upper_bound;
 100
 101         /* v4 specific, but allows fib6_nh with v4 routes */
 102         struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
 103         struct rtable __rcu     *nhc_rth_input;
 104         struct fnhe_hash_bucket __rcu *nhc_exceptions;
 105 };
 106
 107 struct fib_nh {
 108         struct fib_nh_common    nh_common;
 109         struct hlist_node       nh_hash;
 110         struct fib_info         *nh_parent;
 111 #ifdef CONFIG_IP_ROUTE_CLASSID
 112         __u32                   nh_tclassid;
 113 #endif
 114         __be32                  nh_saddr;
 115         int                     nh_saddr_genid;
 116 #define fib_nh_family           nh_common.nhc_family
 117 #define fib_nh_dev              nh_common.nhc_dev
 118 #define fib_nh_dev_tracker      nh_common.nhc_dev_tracker
 119 #define fib_nh_oif              nh_common.nhc_oif
 120 #define fib_nh_flags            nh_common.nhc_flags
 121 #define fib_nh_lws              nh_common.nhc_lwtstate
 122 #define fib_nh_scope            nh_common.nhc_scope
 123 #define fib_nh_gw_family        nh_common.nhc_gw_family
 124 #define fib_nh_gw4              nh_common.nhc_gw.ipv4
 125 #define fib_nh_gw6              nh_common.nhc_gw.ipv6
 126 #define fib_nh_weight           nh_common.nhc_weight
 127 #define fib_nh_upper_bound      nh_common.nhc_upper_bound
 128 };
 129
 130 /*
 131  * This structure contains data shared by many of routes.
 132  */
 133
 134 struct nexthop;
 135
 136 struct fib_info {
 137         struct hlist_node       fib_hash;
 138         struct hlist_node       fib_lhash;
 139         struct list_head        nh_list;
 140         struct net              *fib_net;
 141         refcount_t              fib_treeref;
 142         refcount_t              fib_clntref;
 143         unsigned int            fib_flags;
 144         unsigned char           fib_dead;
 145         unsigned char           fib_protocol;
 146         unsigned char           fib_scope;
 147         unsigned char           fib_type;
 148         __be32                  fib_prefsrc;
 149         u32                     fib_tb_id;
 150         u32                     fib_priority;
 151         struct dst_metrics      *fib_metrics;
 152 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
 153 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
 154 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
 155 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
 156         int                     fib_nhs;
 157         bool                    fib_nh_is_v6;
 158         bool                    nh_updated;
 159         bool                    pfsrc_removed;
 160         struct nexthop          *nh;
 161         struct rcu_head         rcu;
 162         struct fib_nh           fib_nh[] __counted_by(fib_nhs);
 163 };
 164
 165
 166 #ifdef CONFIG_IP_MULTIPLE_TABLES
 167 struct fib_rule;
 168 #endif
 169
 170 struct fib_table;
 171 struct fib_result {
 172         __be32                  prefix;
 173         unsigned char           prefixlen;
 174         unsigned char           nh_sel;
 175         unsigned char           type;
 176         unsigned char           scope;
 177         u32                     tclassid;
 178         dscp_t                  dscp;
 179         struct fib_nh_common    *nhc;
 180         struct fib_info         *fi;
 181         struct fib_table        *table;
 182         struct hlist_head       *fa_head;
 183 };
 184
 185 struct fib_result_nl {
 186         __be32          fl_addr;   /* To be looked up*/
 187         u32             fl_mark;
 188         unsigned char   fl_tos;
 189         unsigned char   fl_scope;
 190         unsigned char   tb_id_in;
 191
 192         unsigned char   tb_id;      /* Results */
 193         unsigned char   prefixlen;
 194         unsigned char   nh_sel;
 195         unsigned char   type;
 196         unsigned char   scope;
 197         int             err;
 198 };
 199
 200 #ifdef CONFIG_IP_MULTIPLE_TABLES
 201 #define FIB_TABLE_HASHSZ 256
 202 #else
 203 #define FIB_TABLE_HASHSZ 2
 204 #endif
 205
 206 __be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
 207                                  unsigned char scope);
 208 __be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
 209
 210 #define FIB_RES_NHC(res)                ((res).nhc)
 211 #define FIB_RES_DEV(res)        (FIB_RES_NHC(res)->nhc_dev)
 212 #define FIB_RES_OIF(res)        (FIB_RES_NHC(res)->nhc_oif)
 213
 214 struct fib_rt_info {
 215         struct fib_info         *fi;
 216         u32                     tb_id;
 217         __be32                  dst;
 218         int                     dst_len;
 219         dscp_t                  dscp;
 220         u8                      type;
 221         u8                      offload:1,
 222                                 trap:1,
 223                                 offload_failed:1,
 224                                 unused:5;
 225 };
 226
 227 struct fib_entry_notifier_info {
 228         struct fib_notifier_info info; /* must be first */
 229         u32 dst;
 230         int dst_len;
 231         struct fib_info *fi;
 232         dscp_t dscp;
 233         u8 type;
 234         u32 tb_id;
 235 };
 236
 237 struct fib_nh_notifier_info {
 238         struct fib_notifier_info info; /* must be first */
 239         struct fib_nh *fib_nh;
 240 };
 241
 242 int call_fib4_notifier(struct notifier_block *nb,
 243                        enum fib_event_type event_type,
 244                        struct fib_notifier_info *info);
 245 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
 246                         struct fib_notifier_info *info);
 247
 248 int __net_init fib4_notifier_init(struct net *net);
 249 void __net_exit fib4_notifier_exit(struct net *net);
 250
 251 void fib_info_notify_update(struct net *net, struct nl_info *info);
 252 int fib_notify(struct net *net, struct notifier_block *nb,
 253                struct netlink_ext_ack *extack);
 254
 255 struct fib_table {
 256         struct hlist_node       tb_hlist;
 257         u32                     tb_id;
 258         int                     tb_num_default;
 259         struct rcu_head         rcu;
 260         unsigned long           *tb_data;
 261         unsigned long           __data[];
 262 };
 263
 264 struct fib_dump_filter {
 265         u32                     table_id;
 266         /* filter_set is an optimization that an entry is set */
 267         bool                    filter_set;
 268         bool                    dump_routes;
 269         bool                    dump_exceptions;
 270         bool                    rtnl_held;
 271         unsigned char           protocol;
 272         unsigned char           rt_type;
 273         unsigned int            flags;
 274         struct net_device       *dev;
 275 };
 276
 277 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
 278                      struct fib_result *res, int fib_flags);
 279 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
 280                      struct netlink_ext_ack *extack);
 281 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
 282                      struct netlink_ext_ack *extack);
 283 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
 284                    struct netlink_callback *cb, struct fib_dump_filter *filter);
 285 int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
 286 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
 287 void fib_table_flush_external(struct fib_table *table);
 288 void fib_free_table(struct fib_table *tb);
 289
 290 #ifndef CONFIG_IP_MULTIPLE_TABLES
 291
 292 #define TABLE_LOCAL_INDEX       (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
 293 #define TABLE_MAIN_INDEX        (RT_TABLE_MAIN  & (FIB_TABLE_HASHSZ - 1))
 294
 295 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
 296 {
 297         struct hlist_node *tb_hlist;
 298         struct hlist_head *ptr;
 299
 300         ptr = id == RT_TABLE_LOCAL ?
 301                 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
 302                 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
 303
 304         tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
 305
 306         return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
 307 }
 308
 309 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
 310 {
 311         return fib_get_table(net, id);
 312 }
 313
 314 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
 315                              struct fib_result *res, unsigned int flags)
 316 {
 317         struct fib_table *tb;
 318         int err = -ENETUNREACH;
 319
 320         rcu_read_lock();
 321
 322         tb = fib_get_table(net, RT_TABLE_MAIN);
 323         if (tb)
 324                 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
 325
 326         if (err == -EAGAIN)
 327                 err = -ENETUNREACH;
 328
 329         rcu_read_unlock();
 330
 331         return err;
 332 }
 333
 334 static inline bool fib4_has_custom_rules(const struct net *net)
 335 {
 336         return false;
 337 }
 338
 339 static inline bool fib4_rule_default(const struct fib_rule *rule)
 340 {
 341         return true;
 342 }
 343
 344 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb,
 345                                   struct netlink_ext_ack *extack)
 346 {
 347         return 0;
 348 }
 349
 350 static inline unsigned int fib4_rules_seq_read(const struct net *net)
 351 {
 352         return 0;
 353 }
 354
 355 static inline bool fib4_rules_early_flow_dissect(struct net *net,
 356                                                  struct sk_buff *skb,
 357                                                  struct flowi4 *fl4,
 358                                                  struct flow_keys *flkeys)
 359 {
 360         return false;
 361 }
 362 #else /* CONFIG_IP_MULTIPLE_TABLES */
 363 int __net_init fib4_rules_init(struct net *net);
 364 void __net_exit fib4_rules_exit(struct net *net);
 365
 366 struct fib_table *fib_new_table(struct net *net, u32 id);
 367 struct fib_table *fib_get_table(struct net *net, u32 id);
 368
 369 int __fib_lookup(struct net *net, struct flowi4 *flp,
 370                  struct fib_result *res, unsigned int flags);
 371
 372 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
 373                              struct fib_result *res, unsigned int flags)
 374 {
 375         struct fib_table *tb;
 376         int err = -ENETUNREACH;
 377
 378         flags |= FIB_LOOKUP_NOREF;
 379         if (net->ipv4.fib_has_custom_rules)
 380                 return __fib_lookup(net, flp, res, flags);
 381
 382         rcu_read_lock();
 383
 384         res->tclassid = 0;
 385
 386         tb = rcu_dereference_rtnl(net->ipv4.fib_main);
 387         if (tb)
 388                 err = fib_table_lookup(tb, flp, res, flags);
 389
 390         if (!err)
 391                 goto out;
 392
 393         tb = rcu_dereference_rtnl(net->ipv4.fib_default);
 394         if (tb)
 395                 err = fib_table_lookup(tb, flp, res, flags);
 396
 397 out:
 398         if (err == -EAGAIN)
 399                 err = -ENETUNREACH;
 400
 401         rcu_read_unlock();
 402
 403         return err;
 404 }
 405
 406 static inline bool fib4_has_custom_rules(const struct net *net)
 407 {
 408         return net->ipv4.fib_has_custom_rules;
 409 }
 410
 411 bool fib4_rule_default(const struct fib_rule *rule);
 412 int fib4_rules_dump(struct net *net, struct notifier_block *nb,
 413                     struct netlink_ext_ack *extack);
 414 unsigned int fib4_rules_seq_read(const struct net *net);
 415
 416 static inline bool fib4_rules_early_flow_dissect(struct net *net,
 417                                                  struct sk_buff *skb,
 418                                                  struct flowi4 *fl4,
 419                                                  struct flow_keys *flkeys)
 420 {
 421         unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
 422
 423         if (!net->ipv4.fib_rules_require_fldissect)
 424                 return false;
 425
 426         memset(flkeys, 0, sizeof(*flkeys));
 427         __skb_flow_dissect(net, skb, &flow_keys_dissector,
 428                            flkeys, NULL, 0, 0, 0, flag);
 429
 430         fl4->fl4_sport = flkeys->ports.src;
 431         fl4->fl4_dport = flkeys->ports.dst;
 432         fl4->flowi4_proto = flkeys->basic.ip_proto;
 433
 434         return true;
 435 }
 436
 437 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 438
 439 static inline bool fib_dscp_masked_match(dscp_t dscp, const struct flowi4 *fl4)
 440 {
 441         return dscp == inet_dsfield_to_dscp(RT_TOS(fl4->flowi4_tos));
 442 }
 443
 444 /* Exported by fib_frontend.c */
 445 extern const struct nla_policy rtm_ipv4_policy[];
 446 void ip_fib_init(void);
 447 int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
 448                     struct netlink_ext_ack *extack);
 449 __be32 fib_compute_spec_dst(struct sk_buff *skb);
 450 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
 451 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
 452                         dscp_t dscp, int oif, struct net_device *dev,
 453                         struct in_device *idev, u32 *itag);
 454
 455 static inline enum skb_drop_reason
 456 fib_validate_source_reason(struct sk_buff *skb, __be32 src, __be32 dst,
 457                            dscp_t dscp, int oif, struct net_device *dev,
 458                            struct in_device *idev, u32 *itag)
 459 {
 460         int err = fib_validate_source(skb, src, dst, dscp, oif, dev, idev,
 461                                       itag);
 462         if (err < 0)
 463                 return -err;
 464         return SKB_NOT_DROPPED_YET;
 465 }
 466
 467 #ifdef CONFIG_IP_ROUTE_CLASSID
 468 static inline int fib_num_tclassid_users(struct net *net)
 469 {
 470         return atomic_read(&net->ipv4.fib_num_tclassid_users);
 471 }
 472 #else
 473 static inline int fib_num_tclassid_users(struct net *net)
 474 {
 475         return 0;
 476 }
 477 #endif
 478 int fib_unmerge(struct net *net);
 479
 480 static inline bool nhc_l3mdev_matches_dev(const struct fib_nh_common *nhc,
 481 const struct net_device *dev)
 482 {
 483         if (nhc->nhc_dev == dev ||
 484             l3mdev_master_ifindex_rcu(nhc->nhc_dev) == dev->ifindex)
 485                 return true;
 486
 487         return false;
 488 }
 489
 490 /* Exported by fib_semantics.c */
 491 int ip_fib_check_default(__be32 gw, struct net_device *dev);
 492 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
 493 int fib_sync_down_addr(struct net_device *dev, __be32 local);
 494 int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
 495 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
 496 void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
 497
 498 /* Fields used for sysctl_fib_multipath_hash_fields.
 499  * Common to IPv4 and IPv6.
 500  *
 501  * Add new fields at the end. This is user API.
 502  */
 503 #define FIB_MULTIPATH_HASH_FIELD_SRC_IP                 BIT(0)
 504 #define FIB_MULTIPATH_HASH_FIELD_DST_IP                 BIT(1)
 505 #define FIB_MULTIPATH_HASH_FIELD_IP_PROTO               BIT(2)
 506 #define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL              BIT(3)
 507 #define FIB_MULTIPATH_HASH_FIELD_SRC_PORT               BIT(4)
 508 #define FIB_MULTIPATH_HASH_FIELD_DST_PORT               BIT(5)
 509 #define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP           BIT(6)
 510 #define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP           BIT(7)
 511 #define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO         BIT(8)
 512 #define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL        BIT(9)
 513 #define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT         BIT(10)
 514 #define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT         BIT(11)
 515
 516 #define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK             \
 517         (FIB_MULTIPATH_HASH_FIELD_SRC_IP |              \
 518          FIB_MULTIPATH_HASH_FIELD_DST_IP |              \
 519          FIB_MULTIPATH_HASH_FIELD_IP_PROTO |            \
 520          FIB_MULTIPATH_HASH_FIELD_FLOWLABEL |           \
 521          FIB_MULTIPATH_HASH_FIELD_SRC_PORT |            \
 522          FIB_MULTIPATH_HASH_FIELD_DST_PORT)
 523
 524 #define FIB_MULTIPATH_HASH_FIELD_INNER_MASK             \
 525         (FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP |        \
 526          FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP |        \
 527          FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO |      \
 528          FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL |     \
 529          FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT |      \
 530          FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)
 531
 532 #define FIB_MULTIPATH_HASH_FIELD_ALL_MASK               \
 533         (FIB_MULTIPATH_HASH_FIELD_OUTER_MASK |          \
 534          FIB_MULTIPATH_HASH_FIELD_INNER_MASK)
 535
 536 #define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK           \
 537         (FIB_MULTIPATH_HASH_FIELD_SRC_IP |              \
 538          FIB_MULTIPATH_HASH_FIELD_DST_IP |              \
 539          FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
 540
 541 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 542 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
 543                        const struct sk_buff *skb, struct flow_keys *flkeys);
 544
 545 static void
 546 fib_multipath_hash_construct_key(siphash_key_t *key, u32 mp_seed)
 547 {
 548         u64 mp_seed_64 = mp_seed;
 549
 550         key->key[0] = (mp_seed_64 << 32) | mp_seed_64;
 551         key->key[1] = key->key[0];
 552 }
 553
 554 static inline u32 fib_multipath_hash_from_keys(const struct net *net,
 555                                                struct flow_keys *keys)
 556 {
 557         siphash_aligned_key_t hash_key;
 558         u32 mp_seed;
 559
 560         mp_seed = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_seed).mp_seed;
 561         fib_multipath_hash_construct_key(&hash_key, mp_seed);
 562
 563         return flow_hash_from_keys_seed(keys, &hash_key);
 564 }
 565 #else
 566 static inline u32 fib_multipath_hash_from_keys(const struct net *net,
 567                                                struct flow_keys *keys)
 568 {
 569         return flow_hash_from_keys(keys);
 570 }
 571 #endif
 572
 573 int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
 574                  struct netlink_ext_ack *extack);
 575 void fib_select_multipath(struct fib_result *res, int hash);
 576 void fib_select_path(struct net *net, struct fib_result *res,
 577                      struct flowi4 *fl4, const struct sk_buff *skb);
 578
 579 int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
 580                 struct fib_config *cfg, int nh_weight,
 581                 struct netlink_ext_ack *extack);
 582 void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
 583 int fib_nh_common_init(struct net *net, struct fib_nh_common *nhc,
 584                        struct nlattr *fc_encap, u16 fc_encap_type,
 585                        void *cfg, gfp_t gfp_flags,
 586                        struct netlink_ext_ack *extack);
 587 void fib_nh_common_release(struct fib_nh_common *nhc);
 588
 589 /* Exported by fib_trie.c */
 590 void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri);
 591 void fib_trie_init(void);
 592 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
 593 bool fib_lookup_good_nhc(const struct fib_nh_common *nhc, int fib_flags,
 594                          const struct flowi4 *flp);
 595
 596 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
 597 {
 598 #ifdef CONFIG_IP_ROUTE_CLASSID
 599         struct fib_nh_common *nhc = res->nhc;
 600 #ifdef CONFIG_IP_MULTIPLE_TABLES
 601         u32 rtag;
 602 #endif
 603         if (nhc->nhc_family == AF_INET) {
 604                 struct fib_nh *nh;
 605
 606                 nh = container_of(nhc, struct fib_nh, nh_common);
 607                 *itag = nh->nh_tclassid << 16;
 608         } else {
 609                 *itag = 0;
 610         }
 611
 612 #ifdef CONFIG_IP_MULTIPLE_TABLES
 613         rtag = res->tclassid;
 614         if (*itag == 0)
 615                 *itag = (rtag<<16);
 616         *itag |= (rtag>>16);
 617 #endif
 618 #endif
 619 }
 620
 621 void fib_flush(struct net *net);
 622 void free_fib_info(struct fib_info *fi);
 623
 624 static inline void fib_info_hold(struct fib_info *fi)
 625 {
 626         refcount_inc(&fi->fib_clntref);
 627 }
 628
 629 static inline void fib_info_put(struct fib_info *fi)
 630 {
 631         if (refcount_dec_and_test(&fi->fib_clntref))
 632                 free_fib_info(fi);
 633 }
 634
 635 #ifdef CONFIG_PROC_FS
 636 int __net_init fib_proc_init(struct net *net);
 637 void __net_exit fib_proc_exit(struct net *net);
 638 #else
 639 static inline int fib_proc_init(struct net *net)
 640 {
 641         return 0;
 642 }
 643 static inline void fib_proc_exit(struct net *net)
 644 {
 645 }
 646 #endif
 647
 648 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
 649
 650 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
 651                           struct fib_dump_filter *filter,
 652                           struct netlink_callback *cb);
 653
 654 int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
 655                      u8 rt_family, unsigned char *flags, bool skip_oif);
 656 int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
 657                     int nh_weight, u8 rt_family, u32 nh_tclassid);
 658 #endif  /* _NET_FIB_H */