linux/include/net/ip_fib.h

/* 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
 *		interface as the means of communication with the user level.
 *
 *		Definitions for the Forwarding Information Base.
 *
 * Authors:	A.N.Kuznetsov, <[email protected]>
 */

#ifndef _NET_IP_FIB_H
#define _NET_IP_FIB_H

#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>

struct fib_config {};

struct fib_info;
struct rtable;

struct fib_nh_exception {};

struct fnhe_hash_bucket {};

#define FNHE_HASH_SHIFT
#define FNHE_HASH_SIZE
#define FNHE_RECLAIM_DEPTH

struct fib_nh_common {};

struct fib_nh {};

/*
 * This structure contains data shared by many of routes.
 */

struct nexthop;

struct fib_info {};


#ifdef CONFIG_IP_MULTIPLE_TABLES
struct fib_rule;
#endif

struct fib_table;
struct fib_result {};

struct fib_result_nl {};

#ifdef CONFIG_IP_MULTIPLE_TABLES
#define FIB_TABLE_HASHSZ
#else
#define FIB_TABLE_HASHSZ
#endif

__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)
#define FIB_RES_DEV(res)
#define FIB_RES_OIF(res)

struct fib_rt_info {};

struct fib_entry_notifier_info {};

struct fib_nh_notifier_info {};

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);

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 fib_dump_filter {};

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
#define TABLE_MAIN_INDEX

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];

	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)
{
	return fib_get_table(net, id);
}

static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
			     struct fib_result *res, unsigned int flags)
{
	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;

	rcu_read_unlock();

	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(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 */
int __net_init fib4_rules_init(struct net *net);
void __net_exit fib4_rules_exit(struct net *net);

struct fib_table *fib_new_table(struct net *net, u32 id);
struct fib_table *fib_get_table(struct net *net, u32 id);

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, unsigned int flags)
{}

static inline bool fib4_has_custom_rules(const struct net *net)
{}

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(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)
{}

#endif /* CONFIG_IP_MULTIPLE_TABLES */

/* Exported by fib_frontend.c */
extern const struct nla_policy rtm_ipv4_policy[];
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,
			u8 tos, int oif, struct net_device *dev,
			struct in_device *idev, u32 *itag);
#ifdef CONFIG_IP_ROUTE_CLASSID
static inline int fib_num_tclassid_users(struct net *net)
{}
#else
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)
{}

/* Exported by fib_semantics.c */
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
#define FIB_MULTIPATH_HASH_FIELD_DST_IP
#define FIB_MULTIPATH_HASH_FIELD_IP_PROTO
#define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL
#define FIB_MULTIPATH_HASH_FIELD_SRC_PORT
#define FIB_MULTIPATH_HASH_FIELD_DST_PORT
#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP
#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP
#define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO
#define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL
#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT
#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT

#define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK

#define FIB_MULTIPATH_HASH_FIELD_INNER_MASK

#define FIB_MULTIPATH_HASH_FIELD_ALL_MASK

#define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK

#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)
{}

static inline u32 fib_multipath_hash_from_keys(const struct net *net,
					       struct flow_keys *keys)
{}
#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);
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 */
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)
{}

void fib_flush(struct net *net);
void free_fib_info(struct fib_info *fi);

static inline void fib_info_hold(struct fib_info *fi)
{}

static inline void fib_info_put(struct fib_info *fi)
{}

#ifdef CONFIG_PROC_FS
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)
{
	return 0;
}
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 */