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Diffstat (limited to 'include/net/route.h')
| -rw-r--r-- | include/net/route.h | 318 |
1 files changed, 318 insertions, 0 deletions
diff --git a/include/net/route.h b/include/net/route.h new file mode 100644 index 000000000..fe22d03af --- /dev/null +++ b/include/net/route.h @@ -0,0 +1,318 @@ +/* + * 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 IP router. + * + * Version: @(#)route.h 1.0.4 05/27/93 + * + * Authors: Ross Biro + * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> + * Fixes: + * Alan Cox : Reformatted. Added ip_rt_local() + * Alan Cox : Support for TCP parameters. + * Alexey Kuznetsov: Major changes for new routing code. + * Mike McLagan : Routing by source + * Robert Olsson : Added rt_cache statistics + * + * 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 _ROUTE_H +#define _ROUTE_H + +#include <net/dst.h> +#include <net/inetpeer.h> +#include <net/flow.h> +#include <net/inet_sock.h> +#include <linux/in_route.h> +#include <linux/rtnetlink.h> +#include <linux/rcupdate.h> +#include <linux/route.h> +#include <linux/ip.h> +#include <linux/cache.h> +#include <linux/security.h> + +/* IPv4 datagram length is stored into 16bit field (tot_len) */ +#define IP_MAX_MTU 0xFFFFU + +#define RTO_ONLINK 0x01 + +#define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE)) +#define RT_CONN_FLAGS_TOS(sk,tos) (RT_TOS(tos) | sock_flag(sk, SOCK_LOCALROUTE)) + +struct fib_nh; +struct fib_info; +struct uncached_list; +struct rtable { + struct dst_entry dst; + + int rt_genid; + unsigned int rt_flags; + __u16 rt_type; + __u8 rt_is_input; + __u8 rt_uses_gateway; + + int rt_iif; + + /* Info on neighbour */ + __be32 rt_gateway; + + /* Miscellaneous cached information */ + u32 rt_pmtu; + + struct list_head rt_uncached; + struct uncached_list *rt_uncached_list; +}; + +static inline bool rt_is_input_route(const struct rtable *rt) +{ + return rt->rt_is_input != 0; +} + +static inline bool rt_is_output_route(const struct rtable *rt) +{ + return rt->rt_is_input == 0; +} + +static inline __be32 rt_nexthop(const struct rtable *rt, __be32 daddr) +{ + if (rt->rt_gateway) + return rt->rt_gateway; + return daddr; +} + +struct ip_rt_acct { + __u32 o_bytes; + __u32 o_packets; + __u32 i_bytes; + __u32 i_packets; +}; + +struct rt_cache_stat { + unsigned int in_slow_tot; + unsigned int in_slow_mc; + unsigned int in_no_route; + unsigned int in_brd; + unsigned int in_martian_dst; + unsigned int in_martian_src; + unsigned int out_slow_tot; + unsigned int out_slow_mc; +}; + +extern struct ip_rt_acct __percpu *ip_rt_acct; + +struct in_device; + +int ip_rt_init(void); +void rt_cache_flush(struct net *net); +void rt_flush_dev(struct net_device *dev); +struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp); +struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp, + struct sock *sk); +struct dst_entry *ipv4_blackhole_route(struct net *net, + struct dst_entry *dst_orig); + +static inline struct rtable *ip_route_output_key(struct net *net, struct flowi4 *flp) +{ + return ip_route_output_flow(net, flp, NULL); +} + +static inline struct rtable *ip_route_output(struct net *net, __be32 daddr, + __be32 saddr, u8 tos, int oif) +{ + struct flowi4 fl4 = { + .flowi4_oif = oif, + .flowi4_tos = tos, + .daddr = daddr, + .saddr = saddr, + }; + return ip_route_output_key(net, &fl4); +} + +static inline struct rtable *ip_route_output_ports(struct net *net, struct flowi4 *fl4, + struct sock *sk, + __be32 daddr, __be32 saddr, + __be16 dport, __be16 sport, + __u8 proto, __u8 tos, int oif) +{ + flowi4_init_output(fl4, oif, sk ? sk->sk_mark : 0, tos, + RT_SCOPE_UNIVERSE, proto, + sk ? inet_sk_flowi_flags(sk) : 0, + daddr, saddr, dport, sport); + if (sk) + security_sk_classify_flow(sk, flowi4_to_flowi(fl4)); + return ip_route_output_flow(net, fl4, sk); +} + +static inline struct rtable *ip_route_output_gre(struct net *net, struct flowi4 *fl4, + __be32 daddr, __be32 saddr, + __be32 gre_key, __u8 tos, int oif) +{ + memset(fl4, 0, sizeof(*fl4)); + fl4->flowi4_oif = oif; + fl4->daddr = daddr; + fl4->saddr = saddr; + fl4->flowi4_tos = tos; + fl4->flowi4_proto = IPPROTO_GRE; + fl4->fl4_gre_key = gre_key; + return ip_route_output_key(net, fl4); +} + +int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src, + u8 tos, struct net_device *devin); + +static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src, + u8 tos, struct net_device *devin) +{ + int err; + + rcu_read_lock(); + err = ip_route_input_noref(skb, dst, src, tos, devin); + if (!err) + skb_dst_force(skb); + rcu_read_unlock(); + + return err; +} + +void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, int oif, + u32 mark, u8 protocol, int flow_flags); +void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu); +void ipv4_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, + u8 protocol, int flow_flags); +void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk); +void ip_rt_send_redirect(struct sk_buff *skb); + +unsigned int inet_addr_type(struct net *net, __be32 addr); +unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, + __be32 addr); +void ip_rt_multicast_event(struct in_device *); +int ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg); +void ip_rt_get_source(u8 *src, struct sk_buff *skb, struct rtable *rt); + +struct in_ifaddr; +void fib_add_ifaddr(struct in_ifaddr *); +void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *); + +static inline void ip_rt_put(struct rtable *rt) +{ + /* dst_release() accepts a NULL parameter. + * We rely on dst being first structure in struct rtable + */ + BUILD_BUG_ON(offsetof(struct rtable, dst) != 0); + dst_release(&rt->dst); +} + +#define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3) + +extern const __u8 ip_tos2prio[16]; + +static inline char rt_tos2priority(u8 tos) +{ + return ip_tos2prio[IPTOS_TOS(tos)>>1]; +} + +/* ip_route_connect() and ip_route_newports() work in tandem whilst + * binding a socket for a new outgoing connection. + * + * In order to use IPSEC properly, we must, in the end, have a + * route that was looked up using all available keys including source + * and destination ports. + * + * However, if a source port needs to be allocated (the user specified + * a wildcard source port) we need to obtain addressing information + * in order to perform that allocation. + * + * So ip_route_connect() looks up a route using wildcarded source and + * destination ports in the key, simply so that we can get a pair of + * addresses to use for port allocation. + * + * Later, once the ports are allocated, ip_route_newports() will make + * another route lookup if needed to make sure we catch any IPSEC + * rules keyed on the port information. + * + * The callers allocate the flow key on their stack, and must pass in + * the same flowi4 object to both the ip_route_connect() and the + * ip_route_newports() calls. + */ + +static inline void ip_route_connect_init(struct flowi4 *fl4, __be32 dst, __be32 src, + u32 tos, int oif, u8 protocol, + __be16 sport, __be16 dport, + struct sock *sk) +{ + __u8 flow_flags = 0; + + if (inet_sk(sk)->transparent) + flow_flags |= FLOWI_FLAG_ANYSRC; + + flowi4_init_output(fl4, oif, sk->sk_mark, tos, RT_SCOPE_UNIVERSE, + protocol, flow_flags, dst, src, dport, sport); +} + +static inline struct rtable *ip_route_connect(struct flowi4 *fl4, + __be32 dst, __be32 src, u32 tos, + int oif, u8 protocol, + __be16 sport, __be16 dport, + struct sock *sk) +{ + struct net *net = sock_net(sk); + struct rtable *rt; + + ip_route_connect_init(fl4, dst, src, tos, oif, protocol, + sport, dport, sk); + + if (!dst || !src) { + rt = __ip_route_output_key(net, fl4); + if (IS_ERR(rt)) + return rt; + ip_rt_put(rt); + flowi4_update_output(fl4, oif, tos, fl4->daddr, fl4->saddr); + } + security_sk_classify_flow(sk, flowi4_to_flowi(fl4)); + return ip_route_output_flow(net, fl4, sk); +} + +static inline struct rtable *ip_route_newports(struct flowi4 *fl4, struct rtable *rt, + __be16 orig_sport, __be16 orig_dport, + __be16 sport, __be16 dport, + struct sock *sk) +{ + if (sport != orig_sport || dport != orig_dport) { + fl4->fl4_dport = dport; + fl4->fl4_sport = sport; + ip_rt_put(rt); + flowi4_update_output(fl4, sk->sk_bound_dev_if, + RT_CONN_FLAGS(sk), fl4->daddr, + fl4->saddr); + security_sk_classify_flow(sk, flowi4_to_flowi(fl4)); + return ip_route_output_flow(sock_net(sk), fl4, sk); + } + return rt; +} + +static inline int inet_iif(const struct sk_buff *skb) +{ + int iif = skb_rtable(skb)->rt_iif; + + if (iif) + return iif; + return skb->skb_iif; +} + +extern int sysctl_ip_default_ttl; + +static inline int ip4_dst_hoplimit(const struct dst_entry *dst) +{ + int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); + + if (hoplimit == 0) + hoplimit = sysctl_ip_default_ttl; + return hoplimit; +} + +#endif /* _ROUTE_H */ |