1 files changed, 449 insertions, 126 deletions

diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index cbf2be37c91a..b4495c38e0a0 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
  * INET		An implementation of the TCP/IP protocol suite for the LINUX
  *		operating system.  INET  is implemented using the  BSD Socket
@@ -6,11 +7,6 @@
  *		Definitions for the Forwarding Information Base.
  *
  * Authors:	A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
- *
- *		This program is free software; you can redistribute it and/or
- *		modify it under the terms of the GNU General Public License
- *		as published by the Free Software Foundation; either version
- *		2 of the License, or (at your option) any later version.
  */
 
 #ifndef _NET_IP_FIB_H
@@ -19,24 +15,35 @@
 #include <net/flow.h>
 #include <linux/seq_file.h>
 #include <linux/rcupdate.h>
+#include <net/fib_notifier.h>
 #include <net/fib_rules.h>
+#include <net/inet_dscp.h>
 #include <net/inetpeer.h>
 #include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/refcount.h>
+#include <linux/ip.h>
+#include <linux/in_route.h>
 
 struct fib_config {
 	u8			fc_dst_len;
-	u8			fc_tos;
+	dscp_t			fc_dscp;
 	u8			fc_protocol;
 	u8			fc_scope;
 	u8			fc_type;
-	/* 3 bytes unused */
+	u8			fc_gw_family;
+	/* 2 bytes unused */
 	u32			fc_table;
 	__be32			fc_dst;
-	__be32			fc_gw;
+	union {
+		__be32		fc_gw4;
+		struct in6_addr	fc_gw6;
+	};
 	int			fc_oif;
 	u32			fc_flags;
 	u32			fc_priority;
 	__be32			fc_prefsrc;
+	u32			fc_nh_id;
 	struct nlattr		*fc_mx;
 	struct rtnexthop	*fc_mp;
 	int			fc_mx_len;
@@ -44,7 +51,9 @@ struct fib_config {
 	u32			fc_flow;
 	u32			fc_nlflags;
 	struct nl_info		fc_nlinfo;
- };
+	struct nlattr		*fc_encap;
+	u16			fc_encap_type;
+};
 
 struct fib_info;
 struct rtable;
@@ -54,73 +63,107 @@ struct fib_nh_exception {
 	int				fnhe_genid;
 	__be32				fnhe_daddr;
 	u32				fnhe_pmtu;
+	bool				fnhe_mtu_locked;
 	__be32				fnhe_gw;
 	unsigned long			fnhe_expires;
 	struct rtable __rcu		*fnhe_rth_input;
 	struct rtable __rcu		*fnhe_rth_output;
 	unsigned long			fnhe_stamp;
+	struct rcu_head			rcu;
 };
 
 struct fnhe_hash_bucket {
 	struct fib_nh_exception __rcu	*chain;
 };
 
-#define FNHE_HASH_SIZE		2048
+#define FNHE_HASH_SHIFT		11
+#define FNHE_HASH_SIZE		(1 << FNHE_HASH_SHIFT)
 #define FNHE_RECLAIM_DEPTH	5
 
+struct fib_nh_common {
+	struct net_device	*nhc_dev;
+	netdevice_tracker	nhc_dev_tracker;
+	int			nhc_oif;
+	unsigned char		nhc_scope;
+	u8			nhc_family;
+	u8			nhc_gw_family;
+	unsigned char		nhc_flags;
+	struct lwtunnel_state	*nhc_lwtstate;
+
+	union {
+		__be32          ipv4;
+		struct in6_addr ipv6;
+	} nhc_gw;
+
+	int			nhc_weight;
+	atomic_t		nhc_upper_bound;
+
+	/* v4 specific, but allows fib6_nh with v4 routes */
+	struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
+	struct rtable __rcu     *nhc_rth_input;
+	struct fnhe_hash_bucket	__rcu *nhc_exceptions;
+};
+
 struct fib_nh {
-	struct net_device	*nh_dev;
+	struct fib_nh_common	nh_common;
 	struct hlist_node	nh_hash;
 	struct fib_info		*nh_parent;
-	unsigned int		nh_flags;
-	unsigned char		nh_scope;
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
-	int			nh_weight;
-	int			nh_power;
-#endif
 #ifdef CONFIG_IP_ROUTE_CLASSID
 	__u32			nh_tclassid;
 #endif
-	int			nh_oif;
-	__be32			nh_gw;
 	__be32			nh_saddr;
 	int			nh_saddr_genid;
-	struct rtable __rcu * __percpu *nh_pcpu_rth_output;
-	struct rtable __rcu	*nh_rth_input;
-	struct fnhe_hash_bucket	*nh_exceptions;
+#define fib_nh_family		nh_common.nhc_family
+#define fib_nh_dev		nh_common.nhc_dev
+#define fib_nh_dev_tracker	nh_common.nhc_dev_tracker
+#define fib_nh_oif		nh_common.nhc_oif
+#define fib_nh_flags		nh_common.nhc_flags
+#define fib_nh_lws		nh_common.nhc_lwtstate
+#define fib_nh_scope		nh_common.nhc_scope
+#define fib_nh_gw_family	nh_common.nhc_gw_family
+#define fib_nh_gw4		nh_common.nhc_gw.ipv4
+#define fib_nh_gw6		nh_common.nhc_gw.ipv6
+#define fib_nh_weight		nh_common.nhc_weight
+#define fib_nh_upper_bound	nh_common.nhc_upper_bound
 };
 
 /*
  * This structure contains data shared by many of routes.
  */
 
+struct nexthop;
+
 struct fib_info {
 	struct hlist_node	fib_hash;
 	struct hlist_node	fib_lhash;
+	struct list_head	nh_list;
 	struct net		*fib_net;
-	int			fib_treeref;
-	atomic_t		fib_clntref;
+	refcount_t		fib_treeref;
+	refcount_t		fib_clntref;
 	unsigned int		fib_flags;
 	unsigned char		fib_dead;
 	unsigned char		fib_protocol;
 	unsigned char		fib_scope;
 	unsigned char		fib_type;
 	__be32			fib_prefsrc;
+	u32			fib_tb_id;
 	u32			fib_priority;
-	u32			*fib_metrics;
-#define fib_mtu fib_metrics[RTAX_MTU-1]
-#define fib_window fib_metrics[RTAX_WINDOW-1]
-#define fib_rtt fib_metrics[RTAX_RTT-1]
-#define fib_advmss fib_metrics[RTAX_ADVMSS-1]
+	struct dst_metrics	*fib_metrics;
+#define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
+#define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
+#define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
+#define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
 	int			fib_nhs;
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
-	int			fib_power;
-#endif
+	bool			fib_nh_is_v6;
+	bool			nh_updated;
+	bool			pfsrc_removed;
+	struct nexthop		*nh;
 	struct rcu_head		rcu;
-	struct fib_nh		fib_nh[0];
-#define fib_dev		fib_nh[0].nh_dev
+	struct fib_nh		fib_nh[] __counted_by(fib_nhs);
 };
 
+int __net_init fib4_semantics_init(struct net *net);
+void __net_exit fib4_semantics_exit(struct net *net);
 
 #ifdef CONFIG_IP_MULTIPLE_TABLES
 struct fib_rule;
@@ -128,14 +171,17 @@ struct fib_rule;
 
 struct fib_table;
 struct fib_result {
-	unsigned char	prefixlen;
-	unsigned char	nh_sel;
-	unsigned char	type;
-	unsigned char	scope;
-	u32		tclassid;
-	struct fib_info *fi;
-	struct fib_table *table;
-	struct list_head *fa_head;
+	__be32			prefix;
+	unsigned char		prefixlen;
+	unsigned char		nh_sel;
+	unsigned char		type;
+	unsigned char		scope;
+	u32			tclassid;
+	dscp_t			dscp;
+	struct fib_nh_common	*nhc;
+	struct fib_info		*fi;
+	struct fib_table	*table;
+	struct hlist_head	*fa_head;
 };
 
 struct fib_result_nl {
@@ -150,67 +196,116 @@ struct fib_result_nl {
 	unsigned char	nh_sel;
 	unsigned char	type;
 	unsigned char	scope;
-	int             err;      
+	int             err;
 };
 
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
-#define FIB_RES_NH(res)		((res).fi->fib_nh[(res).nh_sel])
-#else /* CONFIG_IP_ROUTE_MULTIPATH */
-#define FIB_RES_NH(res)		((res).fi->fib_nh[0])
-#endif /* CONFIG_IP_ROUTE_MULTIPATH */
-
 #ifdef CONFIG_IP_MULTIPLE_TABLES
 #define FIB_TABLE_HASHSZ 256
 #else
 #define FIB_TABLE_HASHSZ 2
 #endif
 
-extern __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
+__be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
+				 unsigned char scope);
+__be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
+
+#define FIB_RES_NHC(res)		((res).nhc)
+#define FIB_RES_DEV(res)	(FIB_RES_NHC(res)->nhc_dev)
+#define FIB_RES_OIF(res)	(FIB_RES_NHC(res)->nhc_oif)
+
+struct fib_rt_info {
+	struct fib_info		*fi;
+	u32			tb_id;
+	__be32			dst;
+	int			dst_len;
+	dscp_t			dscp;
+	u8			type;
+	u8			offload:1,
+				trap:1,
+				offload_failed:1,
+				unused:5;
+};
+
+struct fib_entry_notifier_info {
+	struct fib_notifier_info info; /* must be first */
+	u32 dst;
+	int dst_len;
+	struct fib_info *fi;
+	dscp_t dscp;
+	u8 type;
+	u32 tb_id;
+};
+
+struct fib_nh_notifier_info {
+	struct fib_notifier_info info; /* must be first */
+	struct fib_nh *fib_nh;
+};
 
-#define FIB_RES_SADDR(net, res)				\
-	((FIB_RES_NH(res).nh_saddr_genid ==		\
-	  atomic_read(&(net)->ipv4.dev_addr_genid)) ?	\
-	 FIB_RES_NH(res).nh_saddr :			\
-	 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
-#define FIB_RES_GW(res)			(FIB_RES_NH(res).nh_gw)
-#define FIB_RES_DEV(res)		(FIB_RES_NH(res).nh_dev)
-#define FIB_RES_OIF(res)		(FIB_RES_NH(res).nh_oif)
+int call_fib4_notifier(struct notifier_block *nb,
+		       enum fib_event_type event_type,
+		       struct fib_notifier_info *info);
+int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
+			struct fib_notifier_info *info);
 
-#define FIB_RES_PREFSRC(net, res)	((res).fi->fib_prefsrc ? : \
-					 FIB_RES_SADDR(net, res))
+int __net_init fib4_notifier_init(struct net *net);
+void __net_exit fib4_notifier_exit(struct net *net);
+
+void fib_info_notify_update(struct net *net, struct nl_info *info);
+int fib_notify(struct net *net, struct notifier_block *nb,
+	       struct netlink_ext_ack *extack);
 
 struct fib_table {
 	struct hlist_node	tb_hlist;
 	u32			tb_id;
-	int			tb_default;
 	int			tb_num_default;
-	unsigned long		tb_data[0];
+	struct rcu_head		rcu;
+	unsigned long 		*tb_data;
+	unsigned long		__data[];
 };
 
-extern int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
-			    struct fib_result *res, int fib_flags);
-extern int fib_table_insert(struct fib_table *, struct fib_config *);
-extern int fib_table_delete(struct fib_table *, struct fib_config *);
-extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
-			  struct netlink_callback *cb);
-extern int fib_table_flush(struct fib_table *table);
-extern void fib_free_table(struct fib_table *tb);
-
+struct fib_dump_filter {
+	u32			table_id;
+	/* filter_set is an optimization that an entry is set */
+	bool			filter_set;
+	bool			dump_routes;
+	bool			dump_exceptions;
+	bool			rtnl_held;
+	unsigned char		protocol;
+	unsigned char		rt_type;
+	unsigned int		flags;
+	struct net_device	*dev;
+};
 
+int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
+		     struct fib_result *res, int fib_flags);
+int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
+		     struct netlink_ext_ack *extack);
+int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
+		     struct netlink_ext_ack *extack);
+int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
+		   struct netlink_callback *cb, struct fib_dump_filter *filter);
+int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
+struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
+void fib_table_flush_external(struct fib_table *table);
+void fib_free_table(struct fib_table *tb);
 
 #ifndef CONFIG_IP_MULTIPLE_TABLES
 
-#define TABLE_LOCAL_INDEX	0
-#define TABLE_MAIN_INDEX	1
+#define TABLE_LOCAL_INDEX	(RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
+#define TABLE_MAIN_INDEX	(RT_TABLE_MAIN  & (FIB_TABLE_HASHSZ - 1))
 
 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
 {
+	struct hlist_node *tb_hlist;
 	struct hlist_head *ptr;
 
 	ptr = id == RT_TABLE_LOCAL ?
 		&net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
 		&net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
-	return hlist_entry(ptr->first, struct fib_table, tb_hlist);
+
+	tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
+
+	return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
 }
 
 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
@@ -219,66 +314,162 @@ static inline struct fib_table *fib_new_table(struct net *net, u32 id)
 }
 
 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
-			     struct fib_result *res)
+			     struct fib_result *res, unsigned int flags)
 {
-	struct fib_table *table;
+	struct fib_table *tb;
+	int err = -ENETUNREACH;
+
+	rcu_read_lock();
+
+	tb = fib_get_table(net, RT_TABLE_MAIN);
+	if (tb)
+		err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
+
+	if (err == -EAGAIN)
+		err = -ENETUNREACH;
 
-	table = fib_get_table(net, RT_TABLE_LOCAL);
-	if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF))
-		return 0;
+	rcu_read_unlock();
 
-	table = fib_get_table(net, RT_TABLE_MAIN);
-	if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF))
-		return 0;
-	return -ENETUNREACH;
+	return err;
 }
 
+static inline bool fib4_has_custom_rules(const struct net *net)
+{
+	return false;
+}
+
+static inline bool fib4_rule_default(const struct fib_rule *rule)
+{
+	return true;
+}
+
+static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb,
+				  struct netlink_ext_ack *extack)
+{
+	return 0;
+}
+
+static inline unsigned int fib4_rules_seq_read(const struct net *net)
+{
+	return 0;
+}
+
+static inline bool fib4_rules_early_flow_dissect(struct net *net,
+						 struct sk_buff *skb,
+						 struct flowi4 *fl4,
+						 struct flow_keys *flkeys)
+{
+	return false;
+}
 #else /* CONFIG_IP_MULTIPLE_TABLES */
-extern int __net_init fib4_rules_init(struct net *net);
-extern void __net_exit fib4_rules_exit(struct net *net);
+int __net_init fib4_rules_init(struct net *net);
+void __net_exit fib4_rules_exit(struct net *net);
 
-extern struct fib_table *fib_new_table(struct net *net, u32 id);
-extern struct fib_table *fib_get_table(struct net *net, u32 id);
+struct fib_table *fib_new_table(struct net *net, u32 id);
+struct fib_table *fib_get_table(struct net *net, u32 id);
 
-extern int __fib_lookup(struct net *net, struct flowi4 *flp,
-			struct fib_result *res);
+int __fib_lookup(struct net *net, struct flowi4 *flp,
+		 struct fib_result *res, unsigned int flags);
 
 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
-			     struct fib_result *res)
+			     struct fib_result *res, unsigned int flags)
 {
-	if (!net->ipv4.fib_has_custom_rules) {
-		res->tclassid = 0;
-		if (net->ipv4.fib_local &&
-		    !fib_table_lookup(net->ipv4.fib_local, flp, res,
-				      FIB_LOOKUP_NOREF))
-			return 0;
-		if (net->ipv4.fib_main &&
-		    !fib_table_lookup(net->ipv4.fib_main, flp, res,
-				      FIB_LOOKUP_NOREF))
-			return 0;
-		if (net->ipv4.fib_default &&
-		    !fib_table_lookup(net->ipv4.fib_default, flp, res,
-				      FIB_LOOKUP_NOREF))
-			return 0;
-		return -ENETUNREACH;
-	}
-	return __fib_lookup(net, flp, res);
+	struct fib_table *tb;
+	int err = -ENETUNREACH;
+
+	flags |= FIB_LOOKUP_NOREF;
+	if (net->ipv4.fib_has_custom_rules)
+		return __fib_lookup(net, flp, res, flags);
+
+	rcu_read_lock();
+
+	res->tclassid = 0;
+
+	tb = rcu_dereference_rtnl(net->ipv4.fib_main);
+	if (tb)
+		err = fib_table_lookup(tb, flp, res, flags);
+
+	if (!err)
+		goto out;
+
+	tb = rcu_dereference_rtnl(net->ipv4.fib_default);
+	if (tb)
+		err = fib_table_lookup(tb, flp, res, flags);
+
+out:
+	if (err == -EAGAIN)
+		err = -ENETUNREACH;
+
+	rcu_read_unlock();
+
+	return err;
+}
+
+static inline bool fib4_has_custom_rules(const struct net *net)
+{
+	return net->ipv4.fib_has_custom_rules;
+}
+
+bool fib4_rule_default(const struct fib_rule *rule);
+int fib4_rules_dump(struct net *net, struct notifier_block *nb,
+		    struct netlink_ext_ack *extack);
+unsigned int fib4_rules_seq_read(const struct net *net);
+
+static inline bool fib4_rules_early_flow_dissect(struct net *net,
+						 struct sk_buff *skb,
+						 struct flowi4 *fl4,
+						 struct flow_keys *flkeys)
+{
+	unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
+
+	if (!net->ipv4.fib_rules_require_fldissect)
+		return false;
+
+	memset(flkeys, 0, sizeof(*flkeys));
+	__skb_flow_dissect(net, skb, &flow_keys_dissector,
+			   flkeys, NULL, 0, 0, 0, flag);
+
+	fl4->fl4_sport = flkeys->ports.src;
+	fl4->fl4_dport = flkeys->ports.dst;
+	fl4->flowi4_proto = flkeys->basic.ip_proto;
+
+	return true;
 }
 
 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 
+static inline bool fib_dscp_masked_match(dscp_t dscp, const struct flowi4 *fl4)
+{
+	return dscp == (fl4->flowi4_dscp & INET_DSCP_LEGACY_TOS_MASK);
+}
+
 /* Exported by fib_frontend.c */
 extern const struct nla_policy rtm_ipv4_policy[];
-extern void		ip_fib_init(void);
-extern __be32 fib_compute_spec_dst(struct sk_buff *skb);
-extern int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
-			       u8 tos, int oif, struct net_device *dev,
-			       struct in_device *idev, u32 *itag);
-extern void fib_select_default(struct fib_result *res);
+void ip_fib_init(void);
+int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
+		    struct netlink_ext_ack *extack);
+__be32 fib_compute_spec_dst(struct sk_buff *skb);
+bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
+int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
+			dscp_t dscp, int oif, struct net_device *dev,
+			struct in_device *idev, u32 *itag);
+
+static inline enum skb_drop_reason
+fib_validate_source_reason(struct sk_buff *skb, __be32 src, __be32 dst,
+			   dscp_t dscp, int oif, struct net_device *dev,
+			   struct in_device *idev, u32 *itag)
+{
+	int err = fib_validate_source(skb, src, dst, dscp, oif, dev, idev,
+				      itag);
+	if (err < 0)
+		return -err;
+	return SKB_NOT_DROPPED_YET;
+}
+
 #ifdef CONFIG_IP_ROUTE_CLASSID
 static inline int fib_num_tclassid_users(struct net *net)
 {
-	return net->ipv4.fib_num_tclassid_users;
+	return atomic_read(&net->ipv4.fib_num_tclassid_users);
 }
 #else
 static inline int fib_num_tclassid_users(struct net *net)
@@ -286,25 +477,141 @@ static inline int fib_num_tclassid_users(struct net *net)
 	return 0;
 }
 #endif
+int fib_unmerge(struct net *net);
+
+static inline bool nhc_l3mdev_matches_dev(const struct fib_nh_common *nhc,
+const struct net_device *dev)
+{
+	if (nhc->nhc_dev == dev ||
+	    l3mdev_master_ifindex_rcu(nhc->nhc_dev) == dev->ifindex)
+		return true;
+
+	return false;
+}
 
 /* Exported by fib_semantics.c */
-extern int ip_fib_check_default(__be32 gw, struct net_device *dev);
-extern int fib_sync_down_dev(struct net_device *dev, int force);
-extern int fib_sync_down_addr(struct net *net, __be32 local);
-extern int fib_sync_up(struct net_device *dev);
-extern void fib_select_multipath(struct fib_result *res);
+int ip_fib_check_default(__be32 gw, struct net_device *dev);
+int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
+int fib_sync_down_addr(struct net_device *dev, __be32 local);
+int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
+void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
+void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
+
+/* Fields used for sysctl_fib_multipath_hash_fields.
+ * Common to IPv4 and IPv6.
+ *
+ * Add new fields at the end. This is user API.
+ */
+#define FIB_MULTIPATH_HASH_FIELD_SRC_IP			BIT(0)
+#define FIB_MULTIPATH_HASH_FIELD_DST_IP			BIT(1)
+#define FIB_MULTIPATH_HASH_FIELD_IP_PROTO		BIT(2)
+#define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL		BIT(3)
+#define FIB_MULTIPATH_HASH_FIELD_SRC_PORT		BIT(4)
+#define FIB_MULTIPATH_HASH_FIELD_DST_PORT		BIT(5)
+#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP		BIT(6)
+#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP		BIT(7)
+#define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO		BIT(8)
+#define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL	BIT(9)
+#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT		BIT(10)
+#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT		BIT(11)
+
+#define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK		\
+	(FIB_MULTIPATH_HASH_FIELD_SRC_IP |		\
+	 FIB_MULTIPATH_HASH_FIELD_DST_IP |		\
+	 FIB_MULTIPATH_HASH_FIELD_IP_PROTO |		\
+	 FIB_MULTIPATH_HASH_FIELD_FLOWLABEL |		\
+	 FIB_MULTIPATH_HASH_FIELD_SRC_PORT |		\
+	 FIB_MULTIPATH_HASH_FIELD_DST_PORT)
+
+#define FIB_MULTIPATH_HASH_FIELD_INNER_MASK		\
+	(FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP |	\
+	 FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP |	\
+	 FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO |	\
+	 FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL |	\
+	 FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT |	\
+	 FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)
+
+#define FIB_MULTIPATH_HASH_FIELD_ALL_MASK		\
+	(FIB_MULTIPATH_HASH_FIELD_OUTER_MASK |		\
+	 FIB_MULTIPATH_HASH_FIELD_INNER_MASK)
+
+#define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK		\
+	(FIB_MULTIPATH_HASH_FIELD_SRC_IP |		\
+	 FIB_MULTIPATH_HASH_FIELD_DST_IP |		\
+	 FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
+		       const struct sk_buff *skb, struct flow_keys *flkeys);
+
+static void
+fib_multipath_hash_construct_key(siphash_key_t *key, u32 mp_seed)
+{
+	u64 mp_seed_64 = mp_seed;
+
+	key->key[0] = (mp_seed_64 << 32) | mp_seed_64;
+	key->key[1] = key->key[0];
+}
+
+static inline u32 fib_multipath_hash_from_keys(const struct net *net,
+					       struct flow_keys *keys)
+{
+	siphash_aligned_key_t hash_key;
+	u32 mp_seed;
+
+	mp_seed = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_seed).mp_seed;
+	fib_multipath_hash_construct_key(&hash_key, mp_seed);
+
+	return flow_hash_from_keys_seed(keys, &hash_key);
+}
+#else
+static inline u32 fib_multipath_hash_from_keys(const struct net *net,
+					       struct flow_keys *keys)
+{
+	return flow_hash_from_keys(keys);
+}
+#endif
+
+int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
+		 struct netlink_ext_ack *extack);
+void fib_select_multipath(struct fib_result *res, int hash,
+			  const struct flowi4 *fl4);
+void fib_select_path(struct net *net, struct fib_result *res,
+		     struct flowi4 *fl4, const struct sk_buff *skb);
+
+int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
+		struct fib_config *cfg, int nh_weight,
+		struct netlink_ext_ack *extack);
+void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
+int fib_nh_common_init(struct net *net, struct fib_nh_common *nhc,
+		       struct nlattr *fc_encap, u16 fc_encap_type,
+		       void *cfg, gfp_t gfp_flags,
+		       struct netlink_ext_ack *extack);
+void fib_nh_common_release(struct fib_nh_common *nhc);
 
 /* Exported by fib_trie.c */
-extern void fib_trie_init(void);
-extern struct fib_table *fib_trie_table(u32 id);
+void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri);
+void fib_trie_init(void);
+struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
+bool fib_lookup_good_nhc(const struct fib_nh_common *nhc, int fib_flags,
+			 const struct flowi4 *flp);
 
 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
 {
 #ifdef CONFIG_IP_ROUTE_CLASSID
+	struct fib_nh_common *nhc = res->nhc;
 #ifdef CONFIG_IP_MULTIPLE_TABLES
 	u32 rtag;
 #endif
-	*itag = FIB_RES_NH(*res).nh_tclassid<<16;
+	if (nhc->nhc_family == AF_INET) {
+		struct fib_nh *nh;
+
+		nh = container_of(nhc, struct fib_nh, nh_common);
+		*itag = nh->nh_tclassid << 16;
+	} else {
+		*itag = 0;
+	}
+
 #ifdef CONFIG_IP_MULTIPLE_TABLES
 	rtag = res->tclassid;
 	if (*itag == 0)
@@ -314,17 +621,23 @@ static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
 #endif
 }
 
-extern void free_fib_info(struct fib_info *fi);
+void fib_flush(struct net *net);
+void free_fib_info(struct fib_info *fi);
+
+static inline void fib_info_hold(struct fib_info *fi)
+{
+	refcount_inc(&fi->fib_clntref);
+}
 
 static inline void fib_info_put(struct fib_info *fi)
 {
-	if (atomic_dec_and_test(&fi->fib_clntref))
+	if (refcount_dec_and_test(&fi->fib_clntref))
 		free_fib_info(fi);
 }
 
 #ifdef CONFIG_PROC_FS
-extern int __net_init  fib_proc_init(struct net *net);
-extern void __net_exit fib_proc_exit(struct net *net);
+int __net_init fib_proc_init(struct net *net);
+void __net_exit fib_proc_exit(struct net *net);
 #else
 static inline int fib_proc_init(struct net *net)
 {
@@ -335,4 +648,14 @@ static inline void fib_proc_exit(struct net *net)
 }
 #endif
 
+u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
+
+int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
+			  struct fib_dump_filter *filter,
+			  struct netlink_callback *cb);
+
+int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
+		     u8 rt_family, unsigned char *flags, bool skip_oif);
+int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
+		    int nh_weight, u8 rt_family, u32 nh_tclassid);
 #endif  /* _NET_FIB_H */