11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * INET An implementation of the TCP/IP protocol suite for the LINUX 31da177e4SLinus Torvalds * operating system. INET is implemented using the BSD Socket 41da177e4SLinus Torvalds * interface as the means of communication with the user level. 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * Definitions for the IP router. 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * Version: @(#)route.h 1.0.4 05/27/93 91da177e4SLinus Torvalds * 1002c30a84SJesper Juhl * Authors: Ross Biro 111da177e4SLinus Torvalds * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 121da177e4SLinus Torvalds * Fixes: 131da177e4SLinus Torvalds * Alan Cox : Reformatted. Added ip_rt_local() 141da177e4SLinus Torvalds * Alan Cox : Support for TCP parameters. 151da177e4SLinus Torvalds * Alexey Kuznetsov: Major changes for new routing code. 161da177e4SLinus Torvalds * Mike McLagan : Routing by source 171da177e4SLinus Torvalds * Robert Olsson : Added rt_cache statistics 181da177e4SLinus Torvalds * 191da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or 201da177e4SLinus Torvalds * modify it under the terms of the GNU General Public License 211da177e4SLinus Torvalds * as published by the Free Software Foundation; either version 221da177e4SLinus Torvalds * 2 of the License, or (at your option) any later version. 231da177e4SLinus Torvalds */ 241da177e4SLinus Torvalds #ifndef _ROUTE_H 251da177e4SLinus Torvalds #define _ROUTE_H 261da177e4SLinus Torvalds 271da177e4SLinus Torvalds #include <net/dst.h> 281da177e4SLinus Torvalds #include <net/inetpeer.h> 291da177e4SLinus Torvalds #include <net/flow.h> 3079876874SKOVACS Krisztian #include <net/inet_sock.h> 311da177e4SLinus Torvalds #include <linux/in_route.h> 321da177e4SLinus Torvalds #include <linux/rtnetlink.h> 33c6cffba4SDavid S. Miller #include <linux/rcupdate.h> 341da177e4SLinus Torvalds #include <linux/route.h> 351da177e4SLinus Torvalds #include <linux/ip.h> 361da177e4SLinus Torvalds #include <linux/cache.h> 37beb8d13bSVenkat Yekkirala #include <linux/security.h> 381da177e4SLinus Torvalds 391da177e4SLinus Torvalds #define RTO_ONLINK 0x01 401da177e4SLinus Torvalds 411da177e4SLinus Torvalds #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE)) 421da177e4SLinus Torvalds 431da177e4SLinus Torvalds struct fib_nh; 4462fa8a84SDavid S. Miller struct fib_info; 45fd2c3ef7SEric Dumazet struct rtable { 461da177e4SLinus Torvalds struct dst_entry dst; 471da177e4SLinus Torvalds 4829e75252SEric Dumazet int rt_genid; 4995c96174SEric Dumazet unsigned int rt_flags; 501da177e4SLinus Torvalds __u16 rt_type; 51155e8336SJulian Anastasov __u8 rt_is_input; 52155e8336SJulian Anastasov __u8 rt_uses_gateway; 531da177e4SLinus Torvalds 541da177e4SLinus Torvalds int rt_iif; 551da177e4SLinus Torvalds 561da177e4SLinus Torvalds /* Info on neighbour */ 57f2c3fe24SAl Viro __be32 rt_gateway; 581da177e4SLinus Torvalds 591da177e4SLinus Torvalds /* Miscellaneous cached information */ 605943634fSDavid S. Miller u32 rt_pmtu; 61caacf05eSDavid S. Miller 62caacf05eSDavid S. Miller struct list_head rt_uncached; 631da177e4SLinus Torvalds }; 641da177e4SLinus Torvalds 65b8400f37SSteffen Klassert static inline bool rt_is_input_route(const struct rtable *rt) 66c7537967SDavid S. Miller { 679917e1e8SDavid S. Miller return rt->rt_is_input != 0; 68c7537967SDavid S. Miller } 69c7537967SDavid S. Miller 70b8400f37SSteffen Klassert static inline bool rt_is_output_route(const struct rtable *rt) 71c7537967SDavid S. Miller { 729917e1e8SDavid S. Miller return rt->rt_is_input == 0; 73c7537967SDavid S. Miller } 74c7537967SDavid S. Miller 75f8126f1dSDavid S. Miller static inline __be32 rt_nexthop(const struct rtable *rt, __be32 daddr) 76f8126f1dSDavid S. Miller { 77f8126f1dSDavid S. Miller if (rt->rt_gateway) 78f8126f1dSDavid S. Miller return rt->rt_gateway; 79f8126f1dSDavid S. Miller return daddr; 80f8126f1dSDavid S. Miller } 81f8126f1dSDavid S. Miller 82fd2c3ef7SEric Dumazet struct ip_rt_acct { 831da177e4SLinus Torvalds __u32 o_bytes; 841da177e4SLinus Torvalds __u32 o_packets; 851da177e4SLinus Torvalds __u32 i_bytes; 861da177e4SLinus Torvalds __u32 i_packets; 871da177e4SLinus Torvalds }; 881da177e4SLinus Torvalds 89fd2c3ef7SEric Dumazet struct rt_cache_stat { 901da177e4SLinus Torvalds unsigned int in_hit; 911da177e4SLinus Torvalds unsigned int in_slow_tot; 921da177e4SLinus Torvalds unsigned int in_slow_mc; 931da177e4SLinus Torvalds unsigned int in_no_route; 941da177e4SLinus Torvalds unsigned int in_brd; 951da177e4SLinus Torvalds unsigned int in_martian_dst; 961da177e4SLinus Torvalds unsigned int in_martian_src; 971da177e4SLinus Torvalds unsigned int out_hit; 981da177e4SLinus Torvalds unsigned int out_slow_tot; 991da177e4SLinus Torvalds unsigned int out_slow_mc; 1001da177e4SLinus Torvalds unsigned int gc_total; 1011da177e4SLinus Torvalds unsigned int gc_ignored; 1021da177e4SLinus Torvalds unsigned int gc_goal_miss; 1031da177e4SLinus Torvalds unsigned int gc_dst_overflow; 1041da177e4SLinus Torvalds unsigned int in_hlist_search; 1051da177e4SLinus Torvalds unsigned int out_hlist_search; 1061da177e4SLinus Torvalds }; 1071da177e4SLinus Torvalds 1087d720c3eSTejun Heo extern struct ip_rt_acct __percpu *ip_rt_acct; 1091da177e4SLinus Torvalds 1101da177e4SLinus Torvalds struct in_device; 1111da177e4SLinus Torvalds extern int ip_rt_init(void); 112bafa6d9dSNicolas Dichtel extern void rt_cache_flush(struct net *net); 113caacf05eSDavid S. Miller extern void rt_flush_dev(struct net_device *dev); 114813b3b5dSDavid S. Miller extern struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp); 1159d6ec938SDavid S. Miller extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp, 116b23dd4feSDavid S. Miller struct sock *sk); 1172774c131SDavid S. Miller extern struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig); 118407eadd9SEric Dumazet 1199d6ec938SDavid S. Miller static inline struct rtable *ip_route_output_key(struct net *net, struct flowi4 *flp) 1205bfa787fSDavid S. Miller { 1215bfa787fSDavid S. Miller return ip_route_output_flow(net, flp, NULL); 1225bfa787fSDavid S. Miller } 1235bfa787fSDavid S. Miller 12478fbfd8aSDavid S. Miller static inline struct rtable *ip_route_output(struct net *net, __be32 daddr, 12578fbfd8aSDavid S. Miller __be32 saddr, u8 tos, int oif) 12678fbfd8aSDavid S. Miller { 1279d6ec938SDavid S. Miller struct flowi4 fl4 = { 1289d6ec938SDavid S. Miller .flowi4_oif = oif, 129c5d21c4bSRoland Dreier .flowi4_tos = tos, 1309d6ec938SDavid S. Miller .daddr = daddr, 1319d6ec938SDavid S. Miller .saddr = saddr, 13278fbfd8aSDavid S. Miller }; 1339d6ec938SDavid S. Miller return ip_route_output_key(net, &fl4); 13478fbfd8aSDavid S. Miller } 13578fbfd8aSDavid S. Miller 13631e4543dSDavid S. Miller static inline struct rtable *ip_route_output_ports(struct net *net, struct flowi4 *fl4, 13731e4543dSDavid S. Miller struct sock *sk, 13878fbfd8aSDavid S. Miller __be32 daddr, __be32 saddr, 13978fbfd8aSDavid S. Miller __be16 dport, __be16 sport, 14078fbfd8aSDavid S. Miller __u8 proto, __u8 tos, int oif) 14178fbfd8aSDavid S. Miller { 14231e4543dSDavid S. Miller flowi4_init_output(fl4, oif, sk ? sk->sk_mark : 0, tos, 14394b92b88SDavid S. Miller RT_SCOPE_UNIVERSE, proto, 14494b92b88SDavid S. Miller sk ? inet_sk_flowi_flags(sk) : 0, 14594b92b88SDavid S. Miller daddr, saddr, dport, sport); 14678fbfd8aSDavid S. Miller if (sk) 14731e4543dSDavid S. Miller security_sk_classify_flow(sk, flowi4_to_flowi(fl4)); 14831e4543dSDavid S. Miller return ip_route_output_flow(net, fl4, sk); 14978fbfd8aSDavid S. Miller } 15078fbfd8aSDavid S. Miller 151cbb1e85fSDavid S. Miller static inline struct rtable *ip_route_output_gre(struct net *net, struct flowi4 *fl4, 15278fbfd8aSDavid S. Miller __be32 daddr, __be32 saddr, 15378fbfd8aSDavid S. Miller __be32 gre_key, __u8 tos, int oif) 15478fbfd8aSDavid S. Miller { 155cbb1e85fSDavid S. Miller memset(fl4, 0, sizeof(*fl4)); 156cbb1e85fSDavid S. Miller fl4->flowi4_oif = oif; 157cbb1e85fSDavid S. Miller fl4->daddr = daddr; 158cbb1e85fSDavid S. Miller fl4->saddr = saddr; 159cbb1e85fSDavid S. Miller fl4->flowi4_tos = tos; 160cbb1e85fSDavid S. Miller fl4->flowi4_proto = IPPROTO_GRE; 161cbb1e85fSDavid S. Miller fl4->fl4_gre_key = gre_key; 162cbb1e85fSDavid S. Miller return ip_route_output_key(net, fl4); 16378fbfd8aSDavid S. Miller } 16478fbfd8aSDavid S. Miller 165c6cffba4SDavid S. Miller extern int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src, 16638a424e4SDavid Miller u8 tos, struct net_device *devin); 167407eadd9SEric Dumazet 168c6cffba4SDavid S. Miller static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src, 169c6cffba4SDavid S. Miller u8 tos, struct net_device *devin) 170c6cffba4SDavid S. Miller { 171c6cffba4SDavid S. Miller int err; 172c6cffba4SDavid S. Miller 173c6cffba4SDavid S. Miller rcu_read_lock(); 174c6cffba4SDavid S. Miller err = ip_route_input_noref(skb, dst, src, tos, devin); 175c6cffba4SDavid S. Miller if (!err) 176c6cffba4SDavid S. Miller skb_dst_force(skb); 177c6cffba4SDavid S. Miller rcu_read_unlock(); 178c6cffba4SDavid S. Miller 179c6cffba4SDavid S. Miller return err; 180c6cffba4SDavid S. Miller } 181c6cffba4SDavid S. Miller 18236393395SDavid S. Miller extern void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, 18336393395SDavid S. Miller int oif, u32 mark, u8 protocol, int flow_flags); 18436393395SDavid S. Miller extern void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu); 185b42597e2SDavid S. Miller extern void ipv4_redirect(struct sk_buff *skb, struct net *net, 186b42597e2SDavid S. Miller int oif, u32 mark, u8 protocol, int flow_flags); 187b42597e2SDavid S. Miller extern void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk); 1881da177e4SLinus Torvalds extern void ip_rt_send_redirect(struct sk_buff *skb); 1891da177e4SLinus Torvalds 19095c96174SEric Dumazet extern unsigned int inet_addr_type(struct net *net, __be32 addr); 19195c96174SEric Dumazet extern unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr); 1921da177e4SLinus Torvalds extern void ip_rt_multicast_event(struct in_device *); 1931bad118aSDenis V. Lunev extern int ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg); 1948e36360aSDavid S. Miller extern void ip_rt_get_source(u8 *src, struct sk_buff *skb, struct rtable *rt); 1951da177e4SLinus Torvalds extern int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb); 1961da177e4SLinus Torvalds 1970ff60a45SJamal Hadi Salim struct in_ifaddr; 1980ff60a45SJamal Hadi Salim extern void fib_add_ifaddr(struct in_ifaddr *); 199e6abbaa2SJulian Anastasov extern void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *); 2000ff60a45SJamal Hadi Salim 2011da177e4SLinus Torvalds static inline void ip_rt_put(struct rtable *rt) 2021da177e4SLinus Torvalds { 2036da025faSEric Dumazet /* dst_release() accepts a NULL parameter. 2046da025faSEric Dumazet * We rely on dst being first structure in struct rtable 2056da025faSEric Dumazet */ 2066da025faSEric Dumazet BUILD_BUG_ON(offsetof(struct rtable, dst) != 0); 207d8d1f30bSChangli Gao dst_release(&rt->dst); 2081da177e4SLinus Torvalds } 2091da177e4SLinus Torvalds 2101da177e4SLinus Torvalds #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3) 2111da177e4SLinus Torvalds 2124839c52bSPhilippe De Muyter extern const __u8 ip_tos2prio[16]; 2131da177e4SLinus Torvalds 2141da177e4SLinus Torvalds static inline char rt_tos2priority(u8 tos) 2151da177e4SLinus Torvalds { 2161da177e4SLinus Torvalds return ip_tos2prio[IPTOS_TOS(tos)>>1]; 2171da177e4SLinus Torvalds } 2181da177e4SLinus Torvalds 2192d7192d6SDavid S. Miller /* ip_route_connect() and ip_route_newports() work in tandem whilst 2202d7192d6SDavid S. Miller * binding a socket for a new outgoing connection. 2212d7192d6SDavid S. Miller * 2222d7192d6SDavid S. Miller * In order to use IPSEC properly, we must, in the end, have a 2232d7192d6SDavid S. Miller * route that was looked up using all available keys including source 2242d7192d6SDavid S. Miller * and destination ports. 2252d7192d6SDavid S. Miller * 2262d7192d6SDavid S. Miller * However, if a source port needs to be allocated (the user specified 2272d7192d6SDavid S. Miller * a wildcard source port) we need to obtain addressing information 2282d7192d6SDavid S. Miller * in order to perform that allocation. 2292d7192d6SDavid S. Miller * 2302d7192d6SDavid S. Miller * So ip_route_connect() looks up a route using wildcarded source and 2312d7192d6SDavid S. Miller * destination ports in the key, simply so that we can get a pair of 2322d7192d6SDavid S. Miller * addresses to use for port allocation. 2332d7192d6SDavid S. Miller * 2342d7192d6SDavid S. Miller * Later, once the ports are allocated, ip_route_newports() will make 2352d7192d6SDavid S. Miller * another route lookup if needed to make sure we catch any IPSEC 2362d7192d6SDavid S. Miller * rules keyed on the port information. 2372d7192d6SDavid S. Miller * 2382d7192d6SDavid S. Miller * The callers allocate the flow key on their stack, and must pass in 2392d7192d6SDavid S. Miller * the same flowi4 object to both the ip_route_connect() and the 2402d7192d6SDavid S. Miller * ip_route_newports() calls. 2412d7192d6SDavid S. Miller */ 2422d7192d6SDavid S. Miller 2432d7192d6SDavid S. Miller static inline void ip_route_connect_init(struct flowi4 *fl4, __be32 dst, __be32 src, 2442d7192d6SDavid S. Miller u32 tos, int oif, u8 protocol, 245b23dd4feSDavid S. Miller __be16 sport, __be16 dport, 246b23dd4feSDavid S. Miller struct sock *sk, bool can_sleep) 2471da177e4SLinus Torvalds { 2482d7192d6SDavid S. Miller __u8 flow_flags = 0; 24979876874SKOVACS Krisztian 25079876874SKOVACS Krisztian if (inet_sk(sk)->transparent) 25194b92b88SDavid S. Miller flow_flags |= FLOWI_FLAG_ANYSRC; 2525df65e55SDavid S. Miller if (can_sleep) 25394b92b88SDavid S. Miller flow_flags |= FLOWI_FLAG_CAN_SLEEP; 25494b92b88SDavid S. Miller 2552d7192d6SDavid S. Miller flowi4_init_output(fl4, oif, sk->sk_mark, tos, RT_SCOPE_UNIVERSE, 25694b92b88SDavid S. Miller protocol, flow_flags, dst, src, dport, sport); 2572d7192d6SDavid S. Miller } 2582d7192d6SDavid S. Miller 2592d7192d6SDavid S. Miller static inline struct rtable *ip_route_connect(struct flowi4 *fl4, 2602d7192d6SDavid S. Miller __be32 dst, __be32 src, u32 tos, 2612d7192d6SDavid S. Miller int oif, u8 protocol, 2622d7192d6SDavid S. Miller __be16 sport, __be16 dport, 2632d7192d6SDavid S. Miller struct sock *sk, bool can_sleep) 2642d7192d6SDavid S. Miller { 2652d7192d6SDavid S. Miller struct net *net = sock_net(sk); 2662d7192d6SDavid S. Miller struct rtable *rt; 2672d7192d6SDavid S. Miller 2682d7192d6SDavid S. Miller ip_route_connect_init(fl4, dst, src, tos, oif, protocol, 2692d7192d6SDavid S. Miller sport, dport, sk, can_sleep); 27079876874SKOVACS Krisztian 2711da177e4SLinus Torvalds if (!dst || !src) { 2722d7192d6SDavid S. Miller rt = __ip_route_output_key(net, fl4); 273b23dd4feSDavid S. Miller if (IS_ERR(rt)) 274b23dd4feSDavid S. Miller return rt; 275b23dd4feSDavid S. Miller ip_rt_put(rt); 276e6b45241SJulian Anastasov flowi4_update_output(fl4, oif, tos, fl4->daddr, fl4->saddr); 2771da177e4SLinus Torvalds } 2782d7192d6SDavid S. Miller security_sk_classify_flow(sk, flowi4_to_flowi(fl4)); 2792d7192d6SDavid S. Miller return ip_route_output_flow(net, fl4, sk); 2801da177e4SLinus Torvalds } 2811da177e4SLinus Torvalds 2822d7192d6SDavid S. Miller static inline struct rtable *ip_route_newports(struct flowi4 *fl4, struct rtable *rt, 2832d7192d6SDavid S. Miller __be16 orig_sport, __be16 orig_dport, 2842d7192d6SDavid S. Miller __be16 sport, __be16 dport, 2852d7192d6SDavid S. Miller struct sock *sk) 2861da177e4SLinus Torvalds { 287dca8b089SDavid S. Miller if (sport != orig_sport || dport != orig_dport) { 2882d7192d6SDavid S. Miller fl4->fl4_dport = dport; 2892d7192d6SDavid S. Miller fl4->fl4_sport = sport; 290b23dd4feSDavid S. Miller ip_rt_put(rt); 291e6b45241SJulian Anastasov flowi4_update_output(fl4, sk->sk_bound_dev_if, 292e6b45241SJulian Anastasov RT_CONN_FLAGS(sk), fl4->daddr, 293e6b45241SJulian Anastasov fl4->saddr); 2942d7192d6SDavid S. Miller security_sk_classify_flow(sk, flowi4_to_flowi(fl4)); 2952d7192d6SDavid S. Miller return ip_route_output_flow(sock_net(sk), fl4, sk); 2961da177e4SLinus Torvalds } 297b23dd4feSDavid S. Miller return rt; 2981da177e4SLinus Torvalds } 2991da177e4SLinus Torvalds 3001668e010SKOVACS Krisztian static inline int inet_iif(const struct sk_buff *skb) 3011668e010SKOVACS Krisztian { 30213378cadSDavid S. Miller int iif = skb_rtable(skb)->rt_iif; 30313378cadSDavid S. Miller 30413378cadSDavid S. Miller if (iif) 30513378cadSDavid S. Miller return iif; 30613378cadSDavid S. Miller return skb->skb_iif; 3071668e010SKOVACS Krisztian } 3081668e010SKOVACS Krisztian 309323e126fSDavid S. Miller extern int sysctl_ip_default_ttl; 310323e126fSDavid S. Miller 311323e126fSDavid S. Miller static inline int ip4_dst_hoplimit(const struct dst_entry *dst) 312323e126fSDavid S. Miller { 313323e126fSDavid S. Miller int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); 314323e126fSDavid S. Miller 315323e126fSDavid S. Miller if (hoplimit == 0) 316323e126fSDavid S. Miller hoplimit = sysctl_ip_default_ttl; 317323e126fSDavid S. Miller return hoplimit; 318323e126fSDavid S. Miller } 319323e126fSDavid S. Miller 3201da177e4SLinus Torvalds #endif /* _ROUTE_H */ 321