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Diffstat (limited to '')
-rw-r--r-- | include/net/ip_fib.h | 558 |
1 files changed, 558 insertions, 0 deletions
diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h new file mode 100644 index 000000000..0d3cb34c7 --- /dev/null +++ b/include/net/ip_fib.h @@ -0,0 +1,558 @@ +/* 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, <kuznet@ms2.inr.ac.ru> + */ + +#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/inetpeer.h> +#include <linux/percpu.h> +#include <linux/notifier.h> +#include <linux/refcount.h> + +struct fib_config { + u8 fc_dst_len; + u8 fc_tos; + u8 fc_protocol; + u8 fc_scope; + u8 fc_type; + u8 fc_gw_family; + /* 2 bytes unused */ + u32 fc_table; + __be32 fc_dst; + 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; + int fc_mp_len; + u32 fc_flow; + u32 fc_nlflags; + struct nl_info fc_nlinfo; + struct nlattr *fc_encap; + u16 fc_encap_type; +}; + +struct fib_info; +struct rtable; + +struct fib_nh_exception { + struct fib_nh_exception __rcu *fnhe_next; + 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_SHIFT 11 +#define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT) +#define FNHE_RECLAIM_DEPTH 5 + +struct fib_nh_common { + struct net_device *nhc_dev; + 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 fib_nh_common nh_common; + struct hlist_node nh_hash; + struct fib_info *nh_parent; +#ifdef CONFIG_IP_ROUTE_CLASSID + __u32 nh_tclassid; +#endif + __be32 nh_saddr; + int nh_saddr_genid; +#define fib_nh_family nh_common.nhc_family +#define fib_nh_dev nh_common.nhc_dev +#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; + 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; + 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; + bool fib_nh_is_v6; + bool nh_updated; + bool pfsrc_removed; + struct nexthop *nh; + struct rcu_head rcu; + struct fib_nh fib_nh[]; +}; + + +#ifdef CONFIG_IP_MULTIPLE_TABLES +struct fib_rule; +#endif + +struct fib_table; +struct fib_result { + __be32 prefix; + unsigned char prefixlen; + unsigned char nh_sel; + unsigned char type; + unsigned char scope; + u32 tclassid; + struct fib_nh_common *nhc; + struct fib_info *fi; + struct fib_table *table; + struct hlist_head *fa_head; +}; + +struct fib_result_nl { + __be32 fl_addr; /* To be looked up*/ + u32 fl_mark; + unsigned char fl_tos; + unsigned char fl_scope; + unsigned char tb_id_in; + + unsigned char tb_id; /* Results */ + unsigned char prefixlen; + unsigned char nh_sel; + unsigned char type; + unsigned char scope; + int err; +}; + +#ifdef CONFIG_IP_MULTIPLE_TABLES +#define FIB_TABLE_HASHSZ 256 +#else +#define FIB_TABLE_HASHSZ 2 +#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) ((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; + u8 tos; + u8 type; + u8 offload:1, + trap:1, + unused:6; +}; + +struct fib_entry_notifier_info { + struct fib_notifier_info info; /* must be first */ + u32 dst; + int dst_len; + struct fib_info *fi; + u8 tos; + u8 type; + u32 tb_id; +}; + +struct fib_nh_notifier_info { + struct fib_notifier_info info; /* must be first */ + struct fib_nh *fib_nh; +}; + +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 hlist_node tb_hlist; + u32 tb_id; + int tb_num_default; + struct rcu_head rcu; + unsigned long *tb_data; + unsigned long __data[]; +}; + +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; + 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 (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]; + + 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) +{ + 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(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; + + skb_flow_dissect_flow_keys(skb, flkeys, 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 */ + +/* 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) +{ + return atomic_read(&net->ipv4.fib_num_tclassid_users); +} +#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) +{ + if (nhc->nhc_dev == dev || + l3mdev_master_ifindex_rcu(nhc->nhc_dev) == dev->ifindex) + return true; + + return false; +} + +/* 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); + +#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); +#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) +{ +#ifdef CONFIG_IP_ROUTE_CLASSID + struct fib_nh_common *nhc = res->nhc; +#ifdef CONFIG_IP_MULTIPLE_TABLES + u32 rtag; +#endif + 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) + *itag = (rtag<<16); + *itag |= (rtag>>16); +#endif +#endif +} + +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 (refcount_dec_and_test(&fi->fib_clntref)) + free_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 */ |