xref: /openbmc/linux/include/net/ip_fib.h (revision 7e24a55b2122746c2eef192296fc84624354f895)
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  
26  struct fib_config {
27  	u8			fc_dst_len;
28  	dscp_t			fc_dscp;
29  	u8			fc_protocol;
30  	u8			fc_scope;
31  	u8			fc_type;
32  	u8			fc_gw_family;
33  	/* 2 bytes unused */
34  	u32			fc_table;
35  	__be32			fc_dst;
36  	union {
37  		__be32		fc_gw4;
38  		struct in6_addr	fc_gw6;
39  	};
40  	int			fc_oif;
41  	u32			fc_flags;
42  	u32			fc_priority;
43  	__be32			fc_prefsrc;
44  	u32			fc_nh_id;
45  	struct nlattr		*fc_mx;
46  	struct rtnexthop	*fc_mp;
47  	int			fc_mx_len;
48  	int			fc_mp_len;
49  	u32			fc_flow;
50  	u32			fc_nlflags;
51  	struct nl_info		fc_nlinfo;
52  	struct nlattr		*fc_encap;
53  	u16			fc_encap_type;
54  };
55  
56  struct fib_info;
57  struct rtable;
58  
59  struct fib_nh_exception {
60  	struct fib_nh_exception __rcu	*fnhe_next;
61  	int				fnhe_genid;
62  	__be32				fnhe_daddr;
63  	u32				fnhe_pmtu;
64  	bool				fnhe_mtu_locked;
65  	__be32				fnhe_gw;
66  	unsigned long			fnhe_expires;
67  	struct rtable __rcu		*fnhe_rth_input;
68  	struct rtable __rcu		*fnhe_rth_output;
69  	unsigned long			fnhe_stamp;
70  	struct rcu_head			rcu;
71  };
72  
73  struct fnhe_hash_bucket {
74  	struct fib_nh_exception __rcu	*chain;
75  };
76  
77  #define FNHE_HASH_SHIFT		11
78  #define FNHE_HASH_SIZE		(1 << FNHE_HASH_SHIFT)
79  #define FNHE_RECLAIM_DEPTH	5
80  
81  struct fib_nh_common {
82  	struct net_device	*nhc_dev;
83  	netdevice_tracker	nhc_dev_tracker;
84  	int			nhc_oif;
85  	unsigned char		nhc_scope;
86  	u8			nhc_family;
87  	u8			nhc_gw_family;
88  	unsigned char		nhc_flags;
89  	struct lwtunnel_state	*nhc_lwtstate;
90  
91  	union {
92  		__be32          ipv4;
93  		struct in6_addr ipv6;
94  	} nhc_gw;
95  
96  	int			nhc_weight;
97  	atomic_t		nhc_upper_bound;
98  
99  	/* v4 specific, but allows fib6_nh with v4 routes */
100  	struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
101  	struct rtable __rcu     *nhc_rth_input;
102  	struct fnhe_hash_bucket	__rcu *nhc_exceptions;
103  };
104  
105  struct fib_nh {
106  	struct fib_nh_common	nh_common;
107  	struct hlist_node	nh_hash;
108  	struct fib_info		*nh_parent;
109  #ifdef CONFIG_IP_ROUTE_CLASSID
110  	__u32			nh_tclassid;
111  #endif
112  	__be32			nh_saddr;
113  	int			nh_saddr_genid;
114  #define fib_nh_family		nh_common.nhc_family
115  #define fib_nh_dev		nh_common.nhc_dev
116  #define fib_nh_dev_tracker	nh_common.nhc_dev_tracker
117  #define fib_nh_oif		nh_common.nhc_oif
118  #define fib_nh_flags		nh_common.nhc_flags
119  #define fib_nh_lws		nh_common.nhc_lwtstate
120  #define fib_nh_scope		nh_common.nhc_scope
121  #define fib_nh_gw_family	nh_common.nhc_gw_family
122  #define fib_nh_gw4		nh_common.nhc_gw.ipv4
123  #define fib_nh_gw6		nh_common.nhc_gw.ipv6
124  #define fib_nh_weight		nh_common.nhc_weight
125  #define fib_nh_upper_bound	nh_common.nhc_upper_bound
126  };
127  
128  /*
129   * This structure contains data shared by many of routes.
130   */
131  
132  struct nexthop;
133  
134  struct fib_info {
135  	struct hlist_node	fib_hash;
136  	struct hlist_node	fib_lhash;
137  	struct list_head	nh_list;
138  	struct net		*fib_net;
139  	refcount_t		fib_treeref;
140  	refcount_t		fib_clntref;
141  	unsigned int		fib_flags;
142  	unsigned char		fib_dead;
143  	unsigned char		fib_protocol;
144  	unsigned char		fib_scope;
145  	unsigned char		fib_type;
146  	__be32			fib_prefsrc;
147  	u32			fib_tb_id;
148  	u32			fib_priority;
149  	struct dst_metrics	*fib_metrics;
150  #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
151  #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
152  #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
153  #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
154  	int			fib_nhs;
155  	bool			fib_nh_is_v6;
156  	bool			nh_updated;
157  	bool			pfsrc_removed;
158  	struct nexthop		*nh;
159  	struct rcu_head		rcu;
160  	struct fib_nh		fib_nh[];
161  };
162  
163  
164  #ifdef CONFIG_IP_MULTIPLE_TABLES
165  struct fib_rule;
166  #endif
167  
168  struct fib_table;
169  struct fib_result {
170  	__be32			prefix;
171  	unsigned char		prefixlen;
172  	unsigned char		nh_sel;
173  	unsigned char		type;
174  	unsigned char		scope;
175  	u32			tclassid;
176  	dscp_t			dscp;
177  	struct fib_nh_common	*nhc;
178  	struct fib_info		*fi;
179  	struct fib_table	*table;
180  	struct hlist_head	*fa_head;
181  };
182  
183  struct fib_result_nl {
184  	__be32		fl_addr;   /* To be looked up*/
185  	u32		fl_mark;
186  	unsigned char	fl_tos;
187  	unsigned char   fl_scope;
188  	unsigned char   tb_id_in;
189  
190  	unsigned char   tb_id;      /* Results */
191  	unsigned char	prefixlen;
192  	unsigned char	nh_sel;
193  	unsigned char	type;
194  	unsigned char	scope;
195  	int             err;
196  };
197  
198  #ifdef CONFIG_IP_MULTIPLE_TABLES
199  #define FIB_TABLE_HASHSZ 256
200  #else
201  #define FIB_TABLE_HASHSZ 2
202  #endif
203  
204  __be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
205  				 unsigned char scope);
206  __be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
207  
208  #define FIB_RES_NHC(res)		((res).nhc)
209  #define FIB_RES_DEV(res)	(FIB_RES_NHC(res)->nhc_dev)
210  #define FIB_RES_OIF(res)	(FIB_RES_NHC(res)->nhc_oif)
211  
212  struct fib_rt_info {
213  	struct fib_info		*fi;
214  	u32			tb_id;
215  	__be32			dst;
216  	int			dst_len;
217  	dscp_t			dscp;
218  	u8			type;
219  	u8			offload:1,
220  				trap:1,
221  				offload_failed:1,
222  				unused:5;
223  };
224  
225  struct fib_entry_notifier_info {
226  	struct fib_notifier_info info; /* must be first */
227  	u32 dst;
228  	int dst_len;
229  	struct fib_info *fi;
230  	dscp_t dscp;
231  	u8 type;
232  	u32 tb_id;
233  };
234  
235  struct fib_nh_notifier_info {
236  	struct fib_notifier_info info; /* must be first */
237  	struct fib_nh *fib_nh;
238  };
239  
240  int call_fib4_notifier(struct notifier_block *nb,
241  		       enum fib_event_type event_type,
242  		       struct fib_notifier_info *info);
243  int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
244  			struct fib_notifier_info *info);
245  
246  int __net_init fib4_notifier_init(struct net *net);
247  void __net_exit fib4_notifier_exit(struct net *net);
248  
249  void fib_info_notify_update(struct net *net, struct nl_info *info);
250  int fib_notify(struct net *net, struct notifier_block *nb,
251  	       struct netlink_ext_ack *extack);
252  
253  struct fib_table {
254  	struct hlist_node	tb_hlist;
255  	u32			tb_id;
256  	int			tb_num_default;
257  	struct rcu_head		rcu;
258  	unsigned long 		*tb_data;
259  	unsigned long		__data[];
260  };
261  
262  struct fib_dump_filter {
263  	u32			table_id;
264  	/* filter_set is an optimization that an entry is set */
265  	bool			filter_set;
266  	bool			dump_routes;
267  	bool			dump_exceptions;
268  	unsigned char		protocol;
269  	unsigned char		rt_type;
270  	unsigned int		flags;
271  	struct net_device	*dev;
272  };
273  
274  int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
275  		     struct fib_result *res, int fib_flags);
276  int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
277  		     struct netlink_ext_ack *extack);
278  int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
279  		     struct netlink_ext_ack *extack);
280  int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
281  		   struct netlink_callback *cb, struct fib_dump_filter *filter);
282  int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
283  struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
284  void fib_table_flush_external(struct fib_table *table);
285  void fib_free_table(struct fib_table *tb);
286  
287  #ifndef CONFIG_IP_MULTIPLE_TABLES
288  
289  #define TABLE_LOCAL_INDEX	(RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
290  #define TABLE_MAIN_INDEX	(RT_TABLE_MAIN  & (FIB_TABLE_HASHSZ - 1))
291  
fib_get_table(struct net * net,u32 id)292  static inline struct fib_table *fib_get_table(struct net *net, u32 id)
293  {
294  	struct hlist_node *tb_hlist;
295  	struct hlist_head *ptr;
296  
297  	ptr = id == RT_TABLE_LOCAL ?
298  		&net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
299  		&net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
300  
301  	tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
302  
303  	return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
304  }
305  
fib_new_table(struct net * net,u32 id)306  static inline struct fib_table *fib_new_table(struct net *net, u32 id)
307  {
308  	return fib_get_table(net, id);
309  }
310  
fib_lookup(struct net * net,const struct flowi4 * flp,struct fib_result * res,unsigned int flags)311  static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
312  			     struct fib_result *res, unsigned int flags)
313  {
314  	struct fib_table *tb;
315  	int err = -ENETUNREACH;
316  
317  	rcu_read_lock();
318  
319  	tb = fib_get_table(net, RT_TABLE_MAIN);
320  	if (tb)
321  		err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
322  
323  	if (err == -EAGAIN)
324  		err = -ENETUNREACH;
325  
326  	rcu_read_unlock();
327  
328  	return err;
329  }
330  
fib4_has_custom_rules(const struct net * net)331  static inline bool fib4_has_custom_rules(const struct net *net)
332  {
333  	return false;
334  }
335  
fib4_rule_default(const struct fib_rule * rule)336  static inline bool fib4_rule_default(const struct fib_rule *rule)
337  {
338  	return true;
339  }
340  
fib4_rules_dump(struct net * net,struct notifier_block * nb,struct netlink_ext_ack * extack)341  static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb,
342  				  struct netlink_ext_ack *extack)
343  {
344  	return 0;
345  }
346  
fib4_rules_seq_read(struct net * net)347  static inline unsigned int fib4_rules_seq_read(struct net *net)
348  {
349  	return 0;
350  }
351  
fib4_rules_early_flow_dissect(struct net * net,struct sk_buff * skb,struct flowi4 * fl4,struct flow_keys * flkeys)352  static inline bool fib4_rules_early_flow_dissect(struct net *net,
353  						 struct sk_buff *skb,
354  						 struct flowi4 *fl4,
355  						 struct flow_keys *flkeys)
356  {
357  	return false;
358  }
359  #else /* CONFIG_IP_MULTIPLE_TABLES */
360  int __net_init fib4_rules_init(struct net *net);
361  void __net_exit fib4_rules_exit(struct net *net);
362  
363  struct fib_table *fib_new_table(struct net *net, u32 id);
364  struct fib_table *fib_get_table(struct net *net, u32 id);
365  
366  int __fib_lookup(struct net *net, struct flowi4 *flp,
367  		 struct fib_result *res, unsigned int flags);
368  
fib_lookup(struct net * net,struct flowi4 * flp,struct fib_result * res,unsigned int flags)369  static inline int fib_lookup(struct net *net, struct flowi4 *flp,
370  			     struct fib_result *res, unsigned int flags)
371  {
372  	struct fib_table *tb;
373  	int err = -ENETUNREACH;
374  
375  	flags |= FIB_LOOKUP_NOREF;
376  	if (net->ipv4.fib_has_custom_rules)
377  		return __fib_lookup(net, flp, res, flags);
378  
379  	rcu_read_lock();
380  
381  	res->tclassid = 0;
382  
383  	tb = rcu_dereference_rtnl(net->ipv4.fib_main);
384  	if (tb)
385  		err = fib_table_lookup(tb, flp, res, flags);
386  
387  	if (!err)
388  		goto out;
389  
390  	tb = rcu_dereference_rtnl(net->ipv4.fib_default);
391  	if (tb)
392  		err = fib_table_lookup(tb, flp, res, flags);
393  
394  out:
395  	if (err == -EAGAIN)
396  		err = -ENETUNREACH;
397  
398  	rcu_read_unlock();
399  
400  	return err;
401  }
402  
fib4_has_custom_rules(const struct net * net)403  static inline bool fib4_has_custom_rules(const struct net *net)
404  {
405  	return net->ipv4.fib_has_custom_rules;
406  }
407  
408  bool fib4_rule_default(const struct fib_rule *rule);
409  int fib4_rules_dump(struct net *net, struct notifier_block *nb,
410  		    struct netlink_ext_ack *extack);
411  unsigned int fib4_rules_seq_read(struct net *net);
412  
fib4_rules_early_flow_dissect(struct net * net,struct sk_buff * skb,struct flowi4 * fl4,struct flow_keys * flkeys)413  static inline bool fib4_rules_early_flow_dissect(struct net *net,
414  						 struct sk_buff *skb,
415  						 struct flowi4 *fl4,
416  						 struct flow_keys *flkeys)
417  {
418  	unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
419  
420  	if (!net->ipv4.fib_rules_require_fldissect)
421  		return false;
422  
423  	memset(flkeys, 0, sizeof(*flkeys));
424  	__skb_flow_dissect(net, skb, &flow_keys_dissector,
425  			   flkeys, NULL, 0, 0, 0, flag);
426  
427  	fl4->fl4_sport = flkeys->ports.src;
428  	fl4->fl4_dport = flkeys->ports.dst;
429  	fl4->flowi4_proto = flkeys->basic.ip_proto;
430  
431  	return true;
432  }
433  
434  #endif /* CONFIG_IP_MULTIPLE_TABLES */
435  
436  /* Exported by fib_frontend.c */
437  extern const struct nla_policy rtm_ipv4_policy[];
438  void ip_fib_init(void);
439  int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
440  		    struct netlink_ext_ack *extack);
441  __be32 fib_compute_spec_dst(struct sk_buff *skb);
442  bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
443  int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
444  			u8 tos, int oif, struct net_device *dev,
445  			struct in_device *idev, u32 *itag);
446  #ifdef CONFIG_IP_ROUTE_CLASSID
fib_num_tclassid_users(struct net * net)447  static inline int fib_num_tclassid_users(struct net *net)
448  {
449  	return atomic_read(&net->ipv4.fib_num_tclassid_users);
450  }
451  #else
fib_num_tclassid_users(struct net * net)452  static inline int fib_num_tclassid_users(struct net *net)
453  {
454  	return 0;
455  }
456  #endif
457  int fib_unmerge(struct net *net);
458  
nhc_l3mdev_matches_dev(const struct fib_nh_common * nhc,const struct net_device * dev)459  static inline bool nhc_l3mdev_matches_dev(const struct fib_nh_common *nhc,
460  const struct net_device *dev)
461  {
462  	if (nhc->nhc_dev == dev ||
463  	    l3mdev_master_ifindex_rcu(nhc->nhc_dev) == dev->ifindex)
464  		return true;
465  
466  	return false;
467  }
468  
469  /* Exported by fib_semantics.c */
470  int ip_fib_check_default(__be32 gw, struct net_device *dev);
471  int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
472  int fib_sync_down_addr(struct net_device *dev, __be32 local);
473  int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
474  void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
475  void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
476  
477  /* Fields used for sysctl_fib_multipath_hash_fields.
478   * Common to IPv4 and IPv6.
479   *
480   * Add new fields at the end. This is user API.
481   */
482  #define FIB_MULTIPATH_HASH_FIELD_SRC_IP			BIT(0)
483  #define FIB_MULTIPATH_HASH_FIELD_DST_IP			BIT(1)
484  #define FIB_MULTIPATH_HASH_FIELD_IP_PROTO		BIT(2)
485  #define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL		BIT(3)
486  #define FIB_MULTIPATH_HASH_FIELD_SRC_PORT		BIT(4)
487  #define FIB_MULTIPATH_HASH_FIELD_DST_PORT		BIT(5)
488  #define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP		BIT(6)
489  #define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP		BIT(7)
490  #define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO		BIT(8)
491  #define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL	BIT(9)
492  #define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT		BIT(10)
493  #define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT		BIT(11)
494  
495  #define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK		\
496  	(FIB_MULTIPATH_HASH_FIELD_SRC_IP |		\
497  	 FIB_MULTIPATH_HASH_FIELD_DST_IP |		\
498  	 FIB_MULTIPATH_HASH_FIELD_IP_PROTO |		\
499  	 FIB_MULTIPATH_HASH_FIELD_FLOWLABEL |		\
500  	 FIB_MULTIPATH_HASH_FIELD_SRC_PORT |		\
501  	 FIB_MULTIPATH_HASH_FIELD_DST_PORT)
502  
503  #define FIB_MULTIPATH_HASH_FIELD_INNER_MASK		\
504  	(FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP |	\
505  	 FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP |	\
506  	 FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO |	\
507  	 FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL |	\
508  	 FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT |	\
509  	 FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)
510  
511  #define FIB_MULTIPATH_HASH_FIELD_ALL_MASK		\
512  	(FIB_MULTIPATH_HASH_FIELD_OUTER_MASK |		\
513  	 FIB_MULTIPATH_HASH_FIELD_INNER_MASK)
514  
515  #define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK		\
516  	(FIB_MULTIPATH_HASH_FIELD_SRC_IP |		\
517  	 FIB_MULTIPATH_HASH_FIELD_DST_IP |		\
518  	 FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
519  
520  #ifdef CONFIG_IP_ROUTE_MULTIPATH
521  int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
522  		       const struct sk_buff *skb, struct flow_keys *flkeys);
523  #endif
524  int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
525  		 struct netlink_ext_ack *extack);
526  void fib_select_multipath(struct fib_result *res, int hash);
527  void fib_select_path(struct net *net, struct fib_result *res,
528  		     struct flowi4 *fl4, const struct sk_buff *skb);
529  
530  int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
531  		struct fib_config *cfg, int nh_weight,
532  		struct netlink_ext_ack *extack);
533  void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
534  int fib_nh_common_init(struct net *net, struct fib_nh_common *nhc,
535  		       struct nlattr *fc_encap, u16 fc_encap_type,
536  		       void *cfg, gfp_t gfp_flags,
537  		       struct netlink_ext_ack *extack);
538  void fib_nh_common_release(struct fib_nh_common *nhc);
539  
540  /* Exported by fib_trie.c */
541  void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri);
542  void fib_trie_init(void);
543  struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
544  bool fib_lookup_good_nhc(const struct fib_nh_common *nhc, int fib_flags,
545  			 const struct flowi4 *flp);
546  
fib_combine_itag(u32 * itag,const struct fib_result * res)547  static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
548  {
549  #ifdef CONFIG_IP_ROUTE_CLASSID
550  	struct fib_nh_common *nhc = res->nhc;
551  #ifdef CONFIG_IP_MULTIPLE_TABLES
552  	u32 rtag;
553  #endif
554  	if (nhc->nhc_family == AF_INET) {
555  		struct fib_nh *nh;
556  
557  		nh = container_of(nhc, struct fib_nh, nh_common);
558  		*itag = nh->nh_tclassid << 16;
559  	} else {
560  		*itag = 0;
561  	}
562  
563  #ifdef CONFIG_IP_MULTIPLE_TABLES
564  	rtag = res->tclassid;
565  	if (*itag == 0)
566  		*itag = (rtag<<16);
567  	*itag |= (rtag>>16);
568  #endif
569  #endif
570  }
571  
572  void fib_flush(struct net *net);
573  void free_fib_info(struct fib_info *fi);
574  
fib_info_hold(struct fib_info * fi)575  static inline void fib_info_hold(struct fib_info *fi)
576  {
577  	refcount_inc(&fi->fib_clntref);
578  }
579  
fib_info_put(struct fib_info * fi)580  static inline void fib_info_put(struct fib_info *fi)
581  {
582  	if (refcount_dec_and_test(&fi->fib_clntref))
583  		free_fib_info(fi);
584  }
585  
586  #ifdef CONFIG_PROC_FS
587  int __net_init fib_proc_init(struct net *net);
588  void __net_exit fib_proc_exit(struct net *net);
589  #else
fib_proc_init(struct net * net)590  static inline int fib_proc_init(struct net *net)
591  {
592  	return 0;
593  }
fib_proc_exit(struct net * net)594  static inline void fib_proc_exit(struct net *net)
595  {
596  }
597  #endif
598  
599  u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
600  
601  int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
602  			  struct fib_dump_filter *filter,
603  			  struct netlink_callback *cb);
604  
605  int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
606  		     u8 rt_family, unsigned char *flags, bool skip_oif);
607  int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
608  		    int nh_weight, u8 rt_family, u32 nh_tclassid);
609  #endif  /* _NET_FIB_H */
610