[linux-block.git] / include / net / ip6_fib.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 *	Linux INET6 implementation 
 *
 *	Authors:
 *	Pedro Roque		<roque@di.fc.ul.pt>	
 */

#ifndef _IP6_FIB_H
#define _IP6_FIB_H

#include <linux/ipv6_route.h>
#include <linux/rtnetlink.h>
#include <linux/spinlock.h>
#include <linux/notifier.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/ip_fib.h>
#include <net/netlink.h>
#include <net/inetpeer.h>
#include <net/fib_notifier.h>
#include <linux/indirect_call_wrapper.h>
#include <uapi/linux/bpf.h>

#ifdef CONFIG_IPV6_MULTIPLE_TABLES
#define FIB6_TABLE_HASHSZ 256
#else
#define FIB6_TABLE_HASHSZ 1
#endif

#define RT6_DEBUG 2

#if RT6_DEBUG >= 3
#define RT6_TRACE(x...) pr_debug(x)
#else
#define RT6_TRACE(x...) do { ; } while (0)
#endif

struct rt6_info;
struct fib6_info;

struct fib6_config {
	u32		fc_table;
	u32		fc_metric;
	int		fc_dst_len;
	int		fc_src_len;
	int		fc_ifindex;
	u32		fc_flags;
	u32		fc_protocol;
	u16		fc_type;        /* only 8 bits are used */
	u16		fc_delete_all_nh : 1,
			fc_ignore_dev_down:1,
			__unused : 14;
	u32		fc_nh_id;

	struct in6_addr	fc_dst;
	struct in6_addr	fc_src;
	struct in6_addr	fc_prefsrc;
	struct in6_addr	fc_gateway;

	unsigned long	fc_expires;
	struct nlattr	*fc_mx;
	int		fc_mx_len;
	int		fc_mp_len;
	struct nlattr	*fc_mp;

	struct nl_info	fc_nlinfo;
	struct nlattr	*fc_encap;
	u16		fc_encap_type;
	bool		fc_is_fdb;
};

struct fib6_node {
	struct fib6_node __rcu	*parent;
	struct fib6_node __rcu	*left;
	struct fib6_node __rcu	*right;
#ifdef CONFIG_IPV6_SUBTREES
	struct fib6_node __rcu	*subtree;
#endif
	struct fib6_info __rcu	*leaf;

	__u16			fn_bit;		/* bit key */
	__u16			fn_flags;
	int			fn_sernum;
	struct fib6_info __rcu	*rr_ptr;
	struct rcu_head		rcu;
};

struct fib6_gc_args {
	int			timeout;
	int			more;
};

#ifndef CONFIG_IPV6_SUBTREES
#define FIB6_SUBTREE(fn)	NULL

static inline bool fib6_routes_require_src(const struct net *net)
{
	return false;
}

static inline void fib6_routes_require_src_inc(struct net *net) {}
static inline void fib6_routes_require_src_dec(struct net *net) {}

#else

static inline bool fib6_routes_require_src(const struct net *net)
{
	return net->ipv6.fib6_routes_require_src > 0;
}

static inline void fib6_routes_require_src_inc(struct net *net)
{
	net->ipv6.fib6_routes_require_src++;
}

static inline void fib6_routes_require_src_dec(struct net *net)
{
	net->ipv6.fib6_routes_require_src--;
}

#define FIB6_SUBTREE(fn)	(rcu_dereference_protected((fn)->subtree, 1))
#endif

/*
 *	routing information
 *
 */

struct rt6key {
	struct in6_addr	addr;
	int		plen;
};

struct fib6_table;

struct rt6_exception_bucket {
	struct hlist_head	chain;
	int			depth;
};

struct rt6_exception {
	struct hlist_node	hlist;
	struct rt6_info		*rt6i;
	unsigned long		stamp;
	struct rcu_head		rcu;
};

#define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
#define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
#define FIB6_MAX_DEPTH 5

struct fib6_nh {
	struct fib_nh_common	nh_common;

#ifdef CONFIG_IPV6_ROUTER_PREF
	unsigned long		last_probe;
#endif

	struct rt6_info * __percpu *rt6i_pcpu;
	struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
};

struct fib6_info {
	struct fib6_table		*fib6_table;
	struct fib6_info __rcu		*fib6_next;
	struct fib6_node __rcu		*fib6_node;

	/* Multipath routes:
	 * siblings is a list of fib6_info that have the same metric/weight,
	 * destination, but not the same gateway. nsiblings is just a cache
	 * to speed up lookup.
	 */
	union {
		struct list_head	fib6_siblings;
		struct list_head	nh_list;
	};
	unsigned int			fib6_nsiblings;

	refcount_t			fib6_ref;
	unsigned long			expires;
	struct dst_metrics		*fib6_metrics;
#define fib6_pmtu		fib6_metrics->metrics[RTAX_MTU-1]

	struct rt6key			fib6_dst;
	u32				fib6_flags;
	struct rt6key			fib6_src;
	struct rt6key			fib6_prefsrc;

	u32				fib6_metric;
	u8				fib6_protocol;
	u8				fib6_type;

	u8				offload;
	u8				trap;
	u8				offload_failed;

	u8				should_flush:1,
					dst_nocount:1,
					dst_nopolicy:1,
					fib6_destroying:1,
					unused:4;

	struct rcu_head			rcu;
	struct nexthop			*nh;
	struct fib6_nh			fib6_nh[];
};

struct rt6_info {
	struct dst_entry		dst;
	struct fib6_info __rcu		*from;
	int				sernum;

	struct rt6key			rt6i_dst;
	struct rt6key			rt6i_src;
	struct in6_addr			rt6i_gateway;
	struct inet6_dev		*rt6i_idev;
	u32				rt6i_flags;

	/* more non-fragment space at head required */
	unsigned short			rt6i_nfheader_len;
};

struct fib6_result {
	struct fib6_nh		*nh;
	struct fib6_info	*f6i;
	u32			fib6_flags;
	u8			fib6_type;
	struct rt6_info		*rt6;
};

#define for_each_fib6_node_rt_rcu(fn)					\
	for (rt = rcu_dereference((fn)->leaf); rt;			\
	     rt = rcu_dereference(rt->fib6_next))

#define for_each_fib6_walker_rt(w)					\
	for (rt = (w)->leaf; rt;					\
	     rt = rcu_dereference_protected(rt->fib6_next, 1))

static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
{
	return ((struct rt6_info *)dst)->rt6i_idev;
}

static inline bool fib6_requires_src(const struct fib6_info *rt)
{
	return rt->fib6_src.plen > 0;
}

static inline void fib6_clean_expires(struct fib6_info *f6i)
{
	f6i->fib6_flags &= ~RTF_EXPIRES;
	f6i->expires = 0;
}

static inline void fib6_set_expires(struct fib6_info *f6i,
				    unsigned long expires)
{
	f6i->expires = expires;
	f6i->fib6_flags |= RTF_EXPIRES;
}

static inline bool fib6_check_expired(const struct fib6_info *f6i)
{
	if (f6i->fib6_flags & RTF_EXPIRES)
		return time_after(jiffies, f6i->expires);
	return false;
}

/* Function to safely get fn->fn_sernum for passed in rt
 * and store result in passed in cookie.
 * Return true if we can get cookie safely
 * Return false if not
 */
static inline bool fib6_get_cookie_safe(const struct fib6_info *f6i,
					u32 *cookie)
{
	struct fib6_node *fn;
	bool status = false;

	fn = rcu_dereference(f6i->fib6_node);

	if (fn) {
		*cookie = READ_ONCE(fn->fn_sernum);
		/* pairs with smp_wmb() in __fib6_update_sernum_upto_root() */
		smp_rmb();
		status = true;
	}

	return status;
}

static inline u32 rt6_get_cookie(const struct rt6_info *rt)
{
	struct fib6_info *from;
	u32 cookie = 0;

	if (rt->sernum)
		return rt->sernum;

	rcu_read_lock();

	from = rcu_dereference(rt->from);
	if (from)
		fib6_get_cookie_safe(from, &cookie);

	rcu_read_unlock();

	return cookie;
}

static inline void ip6_rt_put(struct rt6_info *rt)
{
	/* dst_release() accepts a NULL parameter.
	 * We rely on dst being first structure in struct rt6_info
	 */
	BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
	dst_release(&rt->dst);
}

struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh);
void fib6_info_destroy_rcu(struct rcu_head *head);

static inline void fib6_info_hold(struct fib6_info *f6i)
{
	refcount_inc(&f6i->fib6_ref);
}

static inline bool fib6_info_hold_safe(struct fib6_info *f6i)
{
	return refcount_inc_not_zero(&f6i->fib6_ref);
}

static inline void fib6_info_release(struct fib6_info *f6i)
{
	if (f6i && refcount_dec_and_test(&f6i->fib6_ref))
		call_rcu(&f6i->rcu, fib6_info_destroy_rcu);
}

enum fib6_walk_state {
#ifdef CONFIG_IPV6_SUBTREES
	FWS_S,
#endif
	FWS_L,
	FWS_R,
	FWS_C,
	FWS_U
};

struct fib6_walker {
	struct list_head lh;
	struct fib6_node *root, *node;
	struct fib6_info *leaf;
	enum fib6_walk_state state;
	unsigned int skip;
	unsigned int count;
	unsigned int skip_in_node;
	int (*func)(struct fib6_walker *);
	void *args;
};

struct rt6_statistics {
	__u32		fib_nodes;		/* all fib6 nodes */
	__u32		fib_route_nodes;	/* intermediate nodes */
	__u32		fib_rt_entries;		/* rt entries in fib table */
	__u32		fib_rt_cache;		/* cached rt entries in exception table */
	__u32		fib_discarded_routes;	/* total number of routes delete */

	/* The following stat is not protected by any lock */
	atomic_t	fib_rt_alloc;		/* total number of routes alloced */
};

#define RTN_TL_ROOT	0x0001
#define RTN_ROOT	0x0002		/* tree root node		*/
#define RTN_RTINFO	0x0004		/* node with valid routing info	*/

/*
 *	priority levels (or metrics)
 *
 */


struct fib6_table {
	struct hlist_node	tb6_hlist;
	u32			tb6_id;
	spinlock_t		tb6_lock;
	struct fib6_node	tb6_root;
	struct inet_peer_base	tb6_peers;
	unsigned int		flags;
	unsigned int		fib_seq;
#define RT6_TABLE_HAS_DFLT_ROUTER	BIT(0)
};

#define RT6_TABLE_UNSPEC	RT_TABLE_UNSPEC
#define RT6_TABLE_MAIN		RT_TABLE_MAIN
#define RT6_TABLE_DFLT		RT6_TABLE_MAIN
#define RT6_TABLE_INFO		RT6_TABLE_MAIN
#define RT6_TABLE_PREFIX	RT6_TABLE_MAIN

#ifdef CONFIG_IPV6_MULTIPLE_TABLES
#define FIB6_TABLE_MIN		1
#define FIB6_TABLE_MAX		RT_TABLE_MAX
#define RT6_TABLE_LOCAL		RT_TABLE_LOCAL
#else
#define FIB6_TABLE_MIN		RT_TABLE_MAIN
#define FIB6_TABLE_MAX		FIB6_TABLE_MIN
#define RT6_TABLE_LOCAL		RT6_TABLE_MAIN
#endif

typedef struct rt6_info *(*pol_lookup_t)(struct net *,
					 struct fib6_table *,
					 struct flowi6 *,
					 const struct sk_buff *, int);

struct fib6_entry_notifier_info {
	struct fib_notifier_info info; /* must be first */
	struct fib6_info *rt;
	unsigned int nsiblings;
};

/*
 *	exported functions
 */

struct fib6_table *fib6_get_table(struct net *net, u32 id);
struct fib6_table *fib6_new_table(struct net *net, u32 id);
struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
				   const struct sk_buff *skb,
				   int flags, pol_lookup_t lookup);

/* called with rcu lock held; can return error pointer
 * caller needs to select path
 */
int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
		struct fib6_result *res, int flags);

/* called with rcu lock held; caller needs to select path */
int fib6_table_lookup(struct net *net, struct fib6_table *table,
		      int oif, struct flowi6 *fl6, struct fib6_result *res,
		      int strict);

void fib6_select_path(const struct net *net, struct fib6_result *res,
		      struct flowi6 *fl6, int oif, bool have_oif_match,
		      const struct sk_buff *skb, int strict);
struct fib6_node *fib6_node_lookup(struct fib6_node *root,
				   const struct in6_addr *daddr,
				   const struct in6_addr *saddr);

struct fib6_node *fib6_locate(struct fib6_node *root,
			      const struct in6_addr *daddr, int dst_len,
			      const struct in6_addr *saddr, int src_len,
			      bool exact_match);

void fib6_clean_all(struct net *net, int (*func)(struct fib6_info *, void *arg),
		    void *arg);
void fib6_clean_all_skip_notify(struct net *net,
				int (*func)(struct fib6_info *, void *arg),
				void *arg);

int fib6_add(struct fib6_node *root, struct fib6_info *rt,
	     struct nl_info *info, struct netlink_ext_ack *extack);
int fib6_del(struct fib6_info *rt, struct nl_info *info);

static inline
void rt6_get_prefsrc(const struct rt6_info *rt, struct in6_addr *addr)
{
	const struct fib6_info *from;

	rcu_read_lock();

	from = rcu_dereference(rt->from);
	if (from)
		*addr = from->fib6_prefsrc.addr;
	else
		*addr = in6addr_any;

	rcu_read_unlock();
}

int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
		 struct fib6_config *cfg, gfp_t gfp_flags,
		 struct netlink_ext_ack *extack);
void fib6_nh_release(struct fib6_nh *fib6_nh);
void fib6_nh_release_dsts(struct fib6_nh *fib6_nh);

int call_fib6_entry_notifiers(struct net *net,
			      enum fib_event_type event_type,
			      struct fib6_info *rt,
			      struct netlink_ext_ack *extack);
int call_fib6_multipath_entry_notifiers(struct net *net,
					enum fib_event_type event_type,
					struct fib6_info *rt,
					unsigned int nsiblings,
					struct netlink_ext_ack *extack);
int call_fib6_entry_notifiers_replace(struct net *net, struct fib6_info *rt);
void fib6_rt_update(struct net *net, struct fib6_info *rt,
		    struct nl_info *info);
void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
		     unsigned int flags);

void fib6_run_gc(unsigned long expires, struct net *net, bool force);

void fib6_gc_cleanup(void);

int fib6_init(void);

struct ipv6_route_iter {
	struct seq_net_private p;
	struct fib6_walker w;
	loff_t skip;
	struct fib6_table *tbl;
	int sernum;
};

extern const struct seq_operations ipv6_route_seq_ops;

int call_fib6_notifier(struct notifier_block *nb,
		       enum fib_event_type event_type,
		       struct fib_notifier_info *info);
int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
			struct fib_notifier_info *info);

int __net_init fib6_notifier_init(struct net *net);
void __net_exit fib6_notifier_exit(struct net *net);

unsigned int fib6_tables_seq_read(struct net *net);
int fib6_tables_dump(struct net *net, struct notifier_block *nb,
		     struct netlink_ext_ack *extack);

void fib6_update_sernum(struct net *net, struct fib6_info *rt);
void fib6_update_sernum_upto_root(struct net *net, struct fib6_info *rt);
void fib6_update_sernum_stub(struct net *net, struct fib6_info *f6i);

void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
{
	return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
}
void fib6_info_hw_flags_set(struct net *net, struct fib6_info *f6i,
			    bool offload, bool trap, bool offload_failed);

#if IS_BUILTIN(CONFIG_IPV6) && defined(CONFIG_BPF_SYSCALL)
struct bpf_iter__ipv6_route {
	__bpf_md_ptr(struct bpf_iter_meta *, meta);
	__bpf_md_ptr(struct fib6_info *, rt);
};
#endif

INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_output(struct net *net,
					     struct fib6_table *table,
					     struct flowi6 *fl6,
					     const struct sk_buff *skb,
					     int flags));
INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_input(struct net *net,
					     struct fib6_table *table,
					     struct flowi6 *fl6,
					     const struct sk_buff *skb,
					     int flags));
INDIRECT_CALLABLE_DECLARE(struct rt6_info *__ip6_route_redirect(struct net *net,
					     struct fib6_table *table,
					     struct flowi6 *fl6,
					     const struct sk_buff *skb,
					     int flags));
INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_lookup(struct net *net,
					     struct fib6_table *table,
					     struct flowi6 *fl6,
					     const struct sk_buff *skb,
					     int flags));
static inline struct rt6_info *pol_lookup_func(pol_lookup_t lookup,
						struct net *net,
						struct fib6_table *table,
						struct flowi6 *fl6,
						const struct sk_buff *skb,
						int flags)
{
	return INDIRECT_CALL_4(lookup,
			       ip6_pol_route_output,
			       ip6_pol_route_input,
			       ip6_pol_route_lookup,
			       __ip6_route_redirect,
			       net, table, fl6, skb, flags);
}

#ifdef CONFIG_IPV6_MULTIPLE_TABLES
static inline bool fib6_has_custom_rules(const struct net *net)
{
	return net->ipv6.fib6_has_custom_rules;
}

int fib6_rules_init(void);
void fib6_rules_cleanup(void);
bool fib6_rule_default(const struct fib_rule *rule);
int fib6_rules_dump(struct net *net, struct notifier_block *nb,
		    struct netlink_ext_ack *extack);
unsigned int fib6_rules_seq_read(struct net *net);

static inline bool fib6_rules_early_flow_dissect(struct net *net,
						 struct sk_buff *skb,
						 struct flowi6 *fl6,
						 struct flow_keys *flkeys)
{
	unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;

	if (!net->ipv6.fib6_rules_require_fldissect)
		return false;

	skb_flow_dissect_flow_keys(skb, flkeys, flag);
	fl6->fl6_sport = flkeys->ports.src;
	fl6->fl6_dport = flkeys->ports.dst;
	fl6->flowi6_proto = flkeys->basic.ip_proto;

	return true;
}
#else
static inline bool fib6_has_custom_rules(const struct net *net)
{
	return false;
}
static inline int               fib6_rules_init(void)
{
	return 0;
}
static inline void              fib6_rules_cleanup(void)
{
	return ;
}
static inline bool fib6_rule_default(const struct fib_rule *rule)
{
	return true;
}
static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb,
				  struct netlink_ext_ack *extack)
{
	return 0;
}
static inline unsigned int fib6_rules_seq_read(struct net *net)
{
	return 0;
}
static inline bool fib6_rules_early_flow_dissect(struct net *net,
						 struct sk_buff *skb,
						 struct flowi6 *fl6,
						 struct flow_keys *flkeys)
{
	return false;
}
#endif
#endif
Commit	Line	Data
2874c5fd	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
1da177e4 LT	2	/*
	3	* Linux INET6 implementation
	4	*
	5	* Authors:
	6	* Pedro Roque <roque@di.fc.ul.pt>
1da177e4 LT	7	*/
	8
	9	#ifndef _IP6_FIB_H
	10	#define _IP6_FIB_H
	11
1da177e4	12	#include <linux/ipv6_route.h>
1da177e4 LT	13	#include <linux/rtnetlink.h>
1da177e4 LT	14	#include <linux/spinlock.h>
16ab6d7d	15	#include <linux/notifier.h>
86872cb5 TG	16	#include <net/dst.h>
86872cb5 TG	17	#include <net/flow.h>
f1741730	18	#include <net/ip_fib.h>
86872cb5	19	#include <net/netlink.h>
b3419363	20	#include <net/inetpeer.h>
16ab6d7d	21	#include <net/fib_notifier.h>
55cced4f	22	#include <linux/indirect_call_wrapper.h>
3b80b73a	23	#include <uapi/linux/bpf.h>
1da177e4	24
a33bc5c1 NH	25	#ifdef CONFIG_IPV6_MULTIPLE_TABLES
	26	#define FIB6_TABLE_HASHSZ 256
	27	#else
	28	#define FIB6_TABLE_HASHSZ 1
	29	#endif
	30
c757faa8 WW	31	#define RT6_DEBUG 2
	32
	33	#if RT6_DEBUG >= 3
	34	#define RT6_TRACE(x...) pr_debug(x)
	35	#else
	36	#define RT6_TRACE(x...) do { ; } while (0)
	37	#endif
	38
1da177e4	39	struct rt6_info;
a64efe14	40	struct fib6_info;
1da177e4	41
fd2c3ef7	42	struct fib6_config {
86872cb5 TG	43	u32 fc_table;
	44	u32 fc_metric;
	45	int fc_dst_len;
	46	int fc_src_len;
	47	int fc_ifindex;
	48	u32 fc_flags;
	49	u32 fc_protocol;
0ae81335 DA	50	u16 fc_type; /* only 8 bits are used */
0ae81335 DA	51	u16 fc_delete_all_nh : 1,
c7a1ce39 DA	52	fc_ignore_dev_down:1,
c7a1ce39 DA	53	__unused : 14;
5b98324e	54	u32 fc_nh_id;
86872cb5 TG	55
	56	struct in6_addr fc_dst;
	57	struct in6_addr fc_src;
c3968a85	58	struct in6_addr fc_prefsrc;
86872cb5 TG	59	struct in6_addr fc_gateway;
	60
	61	unsigned long fc_expires;
	62	struct nlattr *fc_mx;
	63	int fc_mx_len;
51ebd318 ND	64	int fc_mp_len;
51ebd318 ND	65	struct nlattr *fc_mp;
86872cb5 TG	66
86872cb5 TG	67	struct nl_info fc_nlinfo;
19e42e45 RP	68	struct nlattr *fc_encap;
19e42e45 RP	69	u16 fc_encap_type;
38428d68	70	bool fc_is_fdb;
86872cb5 TG	71	};
86872cb5 TG	72
fd2c3ef7	73	struct fib6_node {
66f5d6ce WW	74	struct fib6_node __rcu *parent;
	75	struct fib6_node __rcu *left;
	76	struct fib6_node __rcu *right;
8bce65b9	77	#ifdef CONFIG_IPV6_SUBTREES
66f5d6ce	78	struct fib6_node __rcu *subtree;
8bce65b9	79	#endif
8d1c802b	80	struct fib6_info __rcu *leaf;
1da177e4 LT	81
	82	__u16 fn_bit; /* bit key */
	83	__u16 fn_flags;
42b18706	84	int fn_sernum;
8d1c802b	85	struct fib6_info __rcu *rr_ptr;
c5cff856	86	struct rcu_head rcu;
1da177e4 LT	87	};
1da177e4 LT	88
c757faa8 WW	89	struct fib6_gc_args {
	90	int timeout;
	91	int more;
	92	};
	93
7fc33165 YH	94	#ifndef CONFIG_IPV6_SUBTREES
7fc33165 YH	95	#define FIB6_SUBTREE(fn) NULL
b9b33e7c PA	96
	97	static inline bool fib6_routes_require_src(const struct net *net)
	98	{
	99	return false;
	100	}
	101
	102	static inline void fib6_routes_require_src_inc(struct net *net) {}
	103	static inline void fib6_routes_require_src_dec(struct net *net) {}
	104
7fc33165	105	#else
b9b33e7c PA	106
	107	static inline bool fib6_routes_require_src(const struct net *net)
	108	{
	109	return net->ipv6.fib6_routes_require_src > 0;
	110	}
	111
	112	static inline void fib6_routes_require_src_inc(struct net *net)
	113	{
	114	net->ipv6.fib6_routes_require_src++;
	115	}
	116
	117	static inline void fib6_routes_require_src_dec(struct net *net)
	118	{
	119	net->ipv6.fib6_routes_require_src--;
	120	}
	121
66f5d6ce	122	#define FIB6_SUBTREE(fn) (rcu_dereference_protected((fn)->subtree, 1))
7fc33165	123	#endif
1da177e4 LT	124
	125	/*
	126	* routing information
	127	*
	128	*/
	129
fd2c3ef7	130	struct rt6key {
1da177e4 LT	131	struct in6_addr addr;
	132	int plen;
	133	};
	134
c71099ac TG	135	struct fib6_table;
c71099ac TG	136
35732d01 WW	137	struct rt6_exception_bucket {
	138	struct hlist_head chain;
	139	int depth;
	140	};
	141
	142	struct rt6_exception {
	143	struct hlist_node hlist;
	144	struct rt6_info *rt6i;
	145	unsigned long stamp;
	146	struct rcu_head rcu;
	147	};
	148
	149	#define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
	150	#define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
	151	#define FIB6_MAX_DEPTH 5
	152
5e670d84	153	struct fib6_nh {
f1741730	154	struct fib_nh_common nh_common;
cc3a86c8 DA	155
	156	#ifdef CONFIG_IPV6_ROUTER_PREF
	157	unsigned long last_probe;
	158	#endif
f40b6ae2 DA	159
f40b6ae2 DA	160	struct rt6_info * __percpu *rt6i_pcpu;
cc5c073a	161	struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
5e670d84	162	};
1da177e4	163
a64efe14	164	struct fib6_info {
93c2fb25	165	struct fib6_table *fib6_table;
8fb11a9a	166	struct fib6_info __rcu *fib6_next;
93c2fb25	167	struct fib6_node __rcu *fib6_node;
1da177e4	168
51ebd318	169	/* Multipath routes:
4b48b0a3	170	* siblings is a list of fib6_info that have the same metric/weight,
51ebd318 ND	171	* destination, but not the same gateway. nsiblings is just a cache
	172	* to speed up lookup.
	173	*/
f88d8ea6 DA	174	union {
	175	struct list_head fib6_siblings;
	176	struct list_head nh_list;
	177	};
93c2fb25	178	unsigned int fib6_nsiblings;
51ebd318	179
f05713e0	180	refcount_t fib6_ref;
a64efe14 DA	181	unsigned long expires;
	182	struct dst_metrics *fib6_metrics;
	183	#define fib6_pmtu fib6_metrics->metrics[RTAX_MTU-1]
a47ed4cd	184
93c2fb25 DA	185	struct rt6key fib6_dst;
	186	u32 fib6_flags;
	187	struct rt6key fib6_src;
	188	struct rt6key fib6_prefsrc;
fe400799	189
93c2fb25 DA	190	u32 fib6_metric;
93c2fb25 DA	191	u8 fib6_protocol;
a64efe14	192	u8 fib6_type;
d95d6320 ED	193
	194	u8 offload;
	195	u8 trap;
	196	u8 offload_failed;
	197
cc5c073a	198	u8 should_flush:1,
a64efe14 DA	199	dst_nocount:1,
a64efe14 DA	200	dst_nopolicy:1,
61fb0d01	201	fib6_destroying:1,
d95d6320	202	unused:4;
a64efe14	203
9b0a8da8	204	struct rcu_head rcu;
f88d8ea6	205	struct nexthop *nh;
6e68f499	206	struct fib6_nh fib6_nh[];
a64efe14 DA	207	};
a64efe14 DA	208
fd2c3ef7	209	struct rt6_info {
d8d1f30b	210	struct dst_entry dst;
a68886a6	211	struct fib6_info __rcu *from;
8f34e53b	212	int sernum;
1da177e4	213
77634cc6	214	struct rt6key rt6i_dst;
bd2c77a0	215	struct rt6key rt6i_src;
1da177e4	216	struct in6_addr rt6i_gateway;
77634cc6	217	struct inet6_dev *rt6i_idev;
bd2c77a0	218	u32 rt6i_flags;
b4ce9277	219
bd2c77a0 YH	220	/* more non-fragment space at head required */
bd2c77a0 YH	221	unsigned short rt6i_nfheader_len;
1da177e4 LT	222	};
1da177e4 LT	223
b1d40991 DA	224	struct fib6_result {
	225	struct fib6_nh *nh;
	226	struct fib6_info *f6i;
7d21fec9 DA	227	u32 fib6_flags;
7d21fec9 DA	228	u8 fib6_type;
a65120ba	229	struct rt6_info *rt6;
b1d40991 DA	230	};
b1d40991 DA	231
66f5d6ce WW	232	#define for_each_fib6_node_rt_rcu(fn) \
66f5d6ce WW	233	for (rt = rcu_dereference((fn)->leaf); rt; \
8fb11a9a	234	rt = rcu_dereference(rt->fib6_next))
66f5d6ce WW	235
	236	#define for_each_fib6_walker_rt(w) \
	237	for (rt = (w)->leaf; rt; \
8fb11a9a	238	rt = rcu_dereference_protected(rt->fib6_next, 1))
66f5d6ce	239
7a3025b1 YH	240	static inline struct inet6_dev ip6_dst_idev(struct dst_entry dst)
	241	{
	242	return ((struct rt6_info *)dst)->rt6i_idev;
	243	}
	244
b9b33e7c PA	245	static inline bool fib6_requires_src(const struct fib6_info *rt)
	246	{
	247	return rt->fib6_src.plen > 0;
	248	}
	249
8d1c802b	250	static inline void fib6_clean_expires(struct fib6_info *f6i)
1716a961	251	{
93c2fb25	252	f6i->fib6_flags &= ~RTF_EXPIRES;
14895687	253	f6i->expires = 0;
1716a961 G	254	}
1716a961 G	255
8d1c802b	256	static inline void fib6_set_expires(struct fib6_info *f6i,
14895687	257	unsigned long expires)
1716a961	258	{
14895687	259	f6i->expires = expires;
93c2fb25	260	f6i->fib6_flags \|= RTF_EXPIRES;
1716a961 G	261	}
1716a961 G	262
8d1c802b	263	static inline bool fib6_check_expired(const struct fib6_info *f6i)
1716a961	264	{
93c2fb25	265	if (f6i->fib6_flags & RTF_EXPIRES)
14895687 DA	266	return time_after(jiffies, f6i->expires);
14895687 DA	267	return false;
1716a961	268	}
b197df4f	269
446e7f21	270	/* Function to safely get fn->fn_sernum for passed in rt
c5cff856 WW	271	* and store result in passed in cookie.
	272	* Return true if we can get cookie safely
	273	* Return false if not
	274	*/
a269f1a7 DA	275	static inline bool fib6_get_cookie_safe(const struct fib6_info *f6i,
a269f1a7 DA	276	u32 *cookie)
c5cff856 WW	277	{
	278	struct fib6_node *fn;
	279	bool status = false;
	280
93c2fb25	281	fn = rcu_dereference(f6i->fib6_node);
c5cff856 WW	282
c5cff856 WW	283	if (fn) {
aafc2e32	284	*cookie = READ_ONCE(fn->fn_sernum);
446e7f21	285	/* pairs with smp_wmb() in __fib6_update_sernum_upto_root() */
bbd63f06	286	smp_rmb();
c5cff856 WW	287	status = true;
	288	}
	289
c5cff856 WW	290	return status;
	291	}
	292
b197df4f MKL	293	static inline u32 rt6_get_cookie(const struct rt6_info *rt)
b197df4f MKL	294	{
a68886a6	295	struct fib6_info *from;
c5cff856 WW	296	u32 cookie = 0;
c5cff856 WW	297
8f34e53b DA	298	if (rt->sernum)
	299	return rt->sernum;
	300
a87b7dc9 DA	301	rcu_read_lock();
a87b7dc9 DA	302
a68886a6	303	from = rcu_dereference(rt->from);
b7999b07	304	if (from)
a68886a6	305	fib6_get_cookie_safe(from, &cookie);
3da59bd9	306
a87b7dc9	307	rcu_read_unlock();
c5cff856 WW	308
c5cff856 WW	309	return cookie;
b197df4f	310	}
1716a961	311
94e187c0 AW	312	static inline void ip6_rt_put(struct rt6_info *rt)
	313	{
	314	/* dst_release() accepts a NULL parameter.
	315	* We rely on dst being first structure in struct rt6_info
	316	*/
	317	BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
	318	dst_release(&rt->dst);
	319	}
	320
1cf844c7	321	struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh);
9b0a8da8	322	void fib6_info_destroy_rcu(struct rcu_head *head);
a460aa83	323
8d1c802b	324	static inline void fib6_info_hold(struct fib6_info *f6i)
a460aa83	325	{
f05713e0	326	refcount_inc(&f6i->fib6_ref);
a460aa83 IS	327	}
a460aa83 IS	328
e873e4b9 WW	329	static inline bool fib6_info_hold_safe(struct fib6_info *f6i)
e873e4b9 WW	330	{
f05713e0	331	return refcount_inc_not_zero(&f6i->fib6_ref);
e873e4b9 WW	332	}
e873e4b9 WW	333
8d1c802b	334	static inline void fib6_info_release(struct fib6_info *f6i)
a460aa83	335	{
f05713e0	336	if (f6i && refcount_dec_and_test(&f6i->fib6_ref))
9b0a8da8	337	call_rcu(&f6i->rcu, fib6_info_destroy_rcu);
a460aa83 IS	338	}
a460aa83 IS	339
94b2cfe0 HFS	340	enum fib6_walk_state {
	341	#ifdef CONFIG_IPV6_SUBTREES
	342	FWS_S,
	343	#endif
	344	FWS_L,
	345	FWS_R,
	346	FWS_C,
	347	FWS_U
	348	};
	349
	350	struct fib6_walker {
bbef49da	351	struct list_head lh;
1da177e4	352	struct fib6_node root, node;
8d1c802b	353	struct fib6_info *leaf;
94b2cfe0	354	enum fib6_walk_state state;
2bec5a36 PM	355	unsigned int skip;
2bec5a36 PM	356	unsigned int count;
1e47b483	357	unsigned int skip_in_node;
94b2cfe0	358	int (func)(struct fib6_walker );
1da177e4 LT	359	void *args;
	360	};
	361
1da177e4	362	struct rt6_statistics {
81eb8447 WW	363	__u32 fib_nodes; /* all fib6 nodes */
	364	__u32 fib_route_nodes; /* intermediate nodes */
	365	__u32 fib_rt_entries; /* rt entries in fib table */
	366	__u32 fib_rt_cache; /* cached rt entries in exception table */
	367	__u32 fib_discarded_routes; /* total number of routes delete */
	368
2d4feb2c	369	/* The following stat is not protected by any lock */
81eb8447	370	atomic_t fib_rt_alloc; /* total number of routes alloced */
1da177e4 LT	371	};
	372
	373	#define RTN_TL_ROOT 0x0001
	374	#define RTN_ROOT 0x0002 /* tree root node */
	375	#define RTN_RTINFO 0x0004 /* node with valid routing info */
	376
	377	/*
	378	* priority levels (or metrics)
	379	*
	380	*/
	381
1da177e4	382
c71099ac TG	383	struct fib6_table {
	384	struct hlist_node tb6_hlist;
	385	u32 tb6_id;
66f5d6ce	386	spinlock_t tb6_lock;
c71099ac	387	struct fib6_node tb6_root;
8e773277	388	struct inet_peer_base tb6_peers;
830218c1	389	unsigned int flags;
e1ee0a5b	390	unsigned int fib_seq;
830218c1	391	#define RT6_TABLE_HAS_DFLT_ROUTER BIT(0)
c71099ac TG	392	};
	393
	394	#define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC
	395	#define RT6_TABLE_MAIN RT_TABLE_MAIN
c71099ac TG	396	#define RT6_TABLE_DFLT RT6_TABLE_MAIN
	397	#define RT6_TABLE_INFO RT6_TABLE_MAIN
	398	#define RT6_TABLE_PREFIX RT6_TABLE_MAIN
	399
	400	#ifdef CONFIG_IPV6_MULTIPLE_TABLES
	401	#define FIB6_TABLE_MIN 1
	402	#define FIB6_TABLE_MAX RT_TABLE_MAX
101367c2	403	#define RT6_TABLE_LOCAL RT_TABLE_LOCAL
c71099ac TG	404	#else
	405	#define FIB6_TABLE_MIN RT_TABLE_MAIN
	406	#define FIB6_TABLE_MAX FIB6_TABLE_MIN
101367c2	407	#define RT6_TABLE_LOCAL RT6_TABLE_MAIN
c71099ac TG	408	#endif
c71099ac TG	409
8ed67789 DL	410	typedef struct rt6_info (pol_lookup_t)(struct net *,
8ed67789 DL	411	struct fib6_table *,
b75cc8f9 DA	412	struct flowi6 *,
b75cc8f9 DA	413	const struct sk_buff *, int);
1da177e4	414
df77fe4d IS	415	struct fib6_entry_notifier_info {
df77fe4d IS	416	struct fib_notifier_info info; /* must be first */
8d1c802b	417	struct fib6_info *rt;
d4b96c7b	418	unsigned int nsiblings;
df77fe4d IS	419	};
df77fe4d IS	420
1da177e4 LT	421	/*
	422	* exported functions
	423	*/
	424
5c3a0fd7 JP	425	struct fib6_table fib6_get_table(struct net net, u32 id);
	426	struct fib6_table fib6_new_table(struct net net, u32 id);
	427	struct dst_entry fib6_rule_lookup(struct net net, struct flowi6 *fl6,
b75cc8f9	428	const struct sk_buff *skb,
5c3a0fd7	429	int flags, pol_lookup_t lookup);
c71099ac	430
138118ec DA	431	/* called with rcu lock held; can return error pointer
	432	* caller needs to select path
	433	*/
effda4dd DA	434	int fib6_lookup(struct net net, int oif, struct flowi6 fl6,
effda4dd DA	435	struct fib6_result *res, int flags);
138118ec	436
1d053da9	437	/* called with rcu lock held; caller needs to select path */
effda4dd DA	438	int fib6_table_lookup(struct net net, struct fib6_table table,
	439	int oif, struct flowi6 fl6, struct fib6_result res,
	440	int strict);
1d053da9	441
b1d40991 DA	442	void fib6_select_path(const struct net net, struct fib6_result res,
	443	struct flowi6 *fl6, int oif, bool have_oif_match,
	444	const struct sk_buff *skb, int strict);
6454743b DA	445	struct fib6_node fib6_node_lookup(struct fib6_node root,
	446	const struct in6_addr *daddr,
	447	const struct in6_addr *saddr);
1da177e4	448
5c3a0fd7 JP	449	struct fib6_node fib6_locate(struct fib6_node root,
5c3a0fd7 JP	450	const struct in6_addr *daddr, int dst_len,
38fbeeee WW	451	const struct in6_addr *saddr, int src_len,
38fbeeee WW	452	bool exact_match);
1da177e4	453
8d1c802b	454	void fib6_clean_all(struct net net, int (func)(struct fib6_info , void arg),
0c3584d5	455	void *arg);
7c6bb7d2 DA	456	void fib6_clean_all_skip_notify(struct net *net,
	457	int (func)(struct fib6_info , void *arg),
	458	void *arg);
c71099ac	459
8d1c802b	460	int fib6_add(struct fib6_node root, struct fib6_info rt,
d4ead6b3	461	struct nl_info info, struct netlink_ext_ack extack);
8d1c802b	462	int fib6_del(struct fib6_info rt, struct nl_info info);
1da177e4	463
67edf21e DA	464	static inline
	465	void rt6_get_prefsrc(const struct rt6_info rt, struct in6_addr addr)
	466	{
	467	const struct fib6_info *from;
	468
	469	rcu_read_lock();
	470
	471	from = rcu_dereference(rt->from);
8cdc3223	472	if (from)
67edf21e	473	*addr = from->fib6_prefsrc.addr;
8cdc3223 KI	474	else
8cdc3223 KI	475	*addr = in6addr_any;
67edf21e DA	476
	477	rcu_read_unlock();
	478	}
9ee8cbb2	479
83c44251 DA	480	int fib6_nh_init(struct net net, struct fib6_nh fib6_nh,
	481	struct fib6_config *cfg, gfp_t gfp_flags,
	482	struct netlink_ext_ack *extack);
dac7d0f2	483	void fib6_nh_release(struct fib6_nh *fib6_nh);
8837cbbf	484	void fib6_nh_release_dsts(struct fib6_nh *fib6_nh);
83c44251	485
19a3b7ee DA	486	int call_fib6_entry_notifiers(struct net *net,
	487	enum fib_event_type event_type,
	488	struct fib6_info *rt,
	489	struct netlink_ext_ack *extack);
d4b96c7b IS	490	int call_fib6_multipath_entry_notifiers(struct net *net,
	491	enum fib_event_type event_type,
	492	struct fib6_info *rt,
	493	unsigned int nsiblings,
	494	struct netlink_ext_ack *extack);
d2f0c9b1	495	int call_fib6_entry_notifiers_replace(struct net net, struct fib6_info rt);
19a3b7ee DA	496	void fib6_rt_update(struct net net, struct fib6_info rt,
19a3b7ee DA	497	struct nl_info *info);
8d1c802b	498	void inet6_rt_notify(int event, struct fib6_info rt, struct nl_info info,
37a1d361	499	unsigned int flags);
1da177e4	500
5c3a0fd7	501	void fib6_run_gc(unsigned long expires, struct net *net, bool force);
1da177e4	502
5c3a0fd7	503	void fib6_gc_cleanup(void);
1da177e4	504
5c3a0fd7	505	int fib6_init(void);
101367c2	506
c3506372 CH	507	struct ipv6_route_iter {
	508	struct seq_net_private p;
	509	struct fib6_walker w;
	510	loff_t skip;
	511	struct fib6_table *tbl;
	512	int sernum;
	513	};
	514
	515	extern const struct seq_operations ipv6_route_seq_ops;
8d2ca1d7	516
7c550daf	517	int call_fib6_notifier(struct notifier_block *nb,
16ab6d7d IS	518	enum fib_event_type event_type,
	519	struct fib_notifier_info *info);
	520	int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
	521	struct fib_notifier_info *info);
	522
	523	int __net_init fib6_notifier_init(struct net *net);
	524	void __net_exit fib6_notifier_exit(struct net *net);
	525
e1ee0a5b	526	unsigned int fib6_tables_seq_read(struct net *net);
b7a59557 JP	527	int fib6_tables_dump(struct net net, struct notifier_block nb,
b7a59557 JP	528	struct netlink_ext_ack *extack);
e1ee0a5b	529
8d1c802b DA	530	void fib6_update_sernum(struct net net, struct fib6_info rt);
8d1c802b DA	531	void fib6_update_sernum_upto_root(struct net net, struct fib6_info rt);
cdaa16a4	532	void fib6_update_sernum_stub(struct net net, struct fib6_info f6i);
180ca444	533
8d1c802b DA	534	void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
8d1c802b DA	535	static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
d4ead6b3 DA	536	{
	537	return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
	538	}
907eea48	539	void fib6_info_hw_flags_set(struct net net, struct fib6_info f6i,
0c5fcf9e	540	bool offload, bool trap, bool offload_failed);
180ca444	541
3c32cc1b YS	542	#if IS_BUILTIN(CONFIG_IPV6) && defined(CONFIG_BPF_SYSCALL)
	543	struct bpf_iter__ipv6_route {
	544	__bpf_md_ptr(struct bpf_iter_meta *, meta);
	545	__bpf_md_ptr(struct fib6_info *, rt);
	546	};
	547	#endif
	548
55cced4f BV	549	INDIRECT_CALLABLE_DECLARE(struct rt6_info ip6_pol_route_output(struct net net,
	550	struct fib6_table *table,
	551	struct flowi6 *fl6,
	552	const struct sk_buff *skb,
	553	int flags));
	554	INDIRECT_CALLABLE_DECLARE(struct rt6_info ip6_pol_route_input(struct net net,
	555	struct fib6_table *table,
	556	struct flowi6 *fl6,
	557	const struct sk_buff *skb,
	558	int flags));
	559	INDIRECT_CALLABLE_DECLARE(struct rt6_info __ip6_route_redirect(struct net net,
	560	struct fib6_table *table,
	561	struct flowi6 *fl6,
	562	const struct sk_buff *skb,
	563	int flags));
	564	INDIRECT_CALLABLE_DECLARE(struct rt6_info ip6_pol_route_lookup(struct net net,
	565	struct fib6_table *table,
	566	struct flowi6 *fl6,
	567	const struct sk_buff *skb,
	568	int flags));
	569	static inline struct rt6_info *pol_lookup_func(pol_lookup_t lookup,
	570	struct net *net,
	571	struct fib6_table *table,
	572	struct flowi6 *fl6,
	573	const struct sk_buff *skb,
	574	int flags)
	575	{
	576	return INDIRECT_CALL_4(lookup,
	577	ip6_pol_route_output,
	578	ip6_pol_route_input,
	579	ip6_pol_route_lookup,
	580	__ip6_route_redirect,
	581	net, table, fl6, skb, flags);
	582	}
	583
7e5449c2	584	#ifdef CONFIG_IPV6_MULTIPLE_TABLES
1f8ac570 PA	585	static inline bool fib6_has_custom_rules(const struct net *net)
	586	{
	587	return net->ipv6.fib6_has_custom_rules;
	588	}
	589
5c3a0fd7 JP	590	int fib6_rules_init(void);
5c3a0fd7 JP	591	void fib6_rules_cleanup(void);
e3ea9731	592	bool fib6_rule_default(const struct fib_rule *rule);
b7a59557 JP	593	int fib6_rules_dump(struct net net, struct notifier_block nb,
b7a59557 JP	594	struct netlink_ext_ack *extack);
dcb18f76	595	unsigned int fib6_rules_seq_read(struct net *net);
5e5d6fed RP	596
	597	static inline bool fib6_rules_early_flow_dissect(struct net *net,
	598	struct sk_buff *skb,
	599	struct flowi6 *fl6,
	600	struct flow_keys *flkeys)
	601	{
	602	unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
	603
	604	if (!net->ipv6.fib6_rules_require_fldissect)
	605	return false;
	606
	607	skb_flow_dissect_flow_keys(skb, flkeys, flag);
	608	fl6->fl6_sport = flkeys->ports.src;
	609	fl6->fl6_dport = flkeys->ports.dst;
	610	fl6->flowi6_proto = flkeys->basic.ip_proto;
	611
	612	return true;
	613	}
7e5449c2	614	#else
1f8ac570 PA	615	static inline bool fib6_has_custom_rules(const struct net *net)
	616	{
	617	return false;
	618	}
7e5449c2 DL	619	static inline int fib6_rules_init(void)
	620	{
	621	return 0;
	622	}
	623	static inline void fib6_rules_cleanup(void)
	624	{
	625	return ;
	626	}
e3ea9731 IS	627	static inline bool fib6_rule_default(const struct fib_rule *rule)
	628	{
	629	return true;
	630	}
b7a59557 JP	631	static inline int fib6_rules_dump(struct net net, struct notifier_block nb,
b7a59557 JP	632	struct netlink_ext_ack *extack)
dcb18f76 IS	633	{
	634	return 0;
	635	}
	636	static inline unsigned int fib6_rules_seq_read(struct net *net)
	637	{
	638	return 0;
	639	}
5e5d6fed RP	640	static inline bool fib6_rules_early_flow_dissect(struct net *net,
	641	struct sk_buff *skb,
	642	struct flowi6 *fl6,
	643	struct flow_keys *flkeys)
	644	{
	645	return false;
	646	}
7e5449c2	647	#endif
1da177e4	648	#endif