When a device is unregistered, we have to purge all of the references to it that may exist in the entire system. If a route is uncached, we currently have no way of accomplishing this. So create a global list that is scanned when a network device goes down. This mirrors the logic in net/core/dst.c's dst_ifdown(). Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			316 lines
		
	
	
	
		
			8.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			316 lines
		
	
	
	
		
			8.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * 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>
 | 
						|
 | 
						|
#define RTO_ONLINK	0x01
 | 
						|
 | 
						|
#define RT_CONN_FLAGS(sk)   (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))
 | 
						|
 | 
						|
struct fib_nh;
 | 
						|
struct fib_info;
 | 
						|
struct rtable {
 | 
						|
	struct dst_entry	dst;
 | 
						|
 | 
						|
	int			rt_genid;
 | 
						|
	unsigned int		rt_flags;
 | 
						|
	__u16			rt_type;
 | 
						|
	__u16			rt_is_input;
 | 
						|
 | 
						|
	int			rt_iif;
 | 
						|
 | 
						|
	/* Info on neighbour */
 | 
						|
	__be32			rt_gateway;
 | 
						|
 | 
						|
	/* Miscellaneous cached information */
 | 
						|
	u32			rt_pmtu;
 | 
						|
 | 
						|
	struct list_head	rt_uncached;
 | 
						|
};
 | 
						|
 | 
						|
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_hit;
 | 
						|
        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_hit;
 | 
						|
        unsigned int out_slow_tot;
 | 
						|
        unsigned int out_slow_mc;
 | 
						|
        unsigned int gc_total;
 | 
						|
        unsigned int gc_ignored;
 | 
						|
        unsigned int gc_goal_miss;
 | 
						|
        unsigned int gc_dst_overflow;
 | 
						|
        unsigned int in_hlist_search;
 | 
						|
        unsigned int out_hlist_search;
 | 
						|
};
 | 
						|
 | 
						|
extern struct ip_rt_acct __percpu *ip_rt_acct;
 | 
						|
 | 
						|
struct in_device;
 | 
						|
extern int		ip_rt_init(void);
 | 
						|
extern void		rt_cache_flush(struct net *net, int how);
 | 
						|
extern void		rt_flush_dev(struct net_device *dev);
 | 
						|
extern struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp);
 | 
						|
extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
 | 
						|
					   struct sock *sk);
 | 
						|
extern 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);
 | 
						|
}
 | 
						|
 | 
						|
extern 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;
 | 
						|
}
 | 
						|
 | 
						|
extern void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
 | 
						|
			     int oif, u32 mark, u8 protocol, int flow_flags);
 | 
						|
extern void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu);
 | 
						|
extern void ipv4_redirect(struct sk_buff *skb, struct net *net,
 | 
						|
			  int oif, u32 mark, u8 protocol, int flow_flags);
 | 
						|
extern void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk);
 | 
						|
extern void ip_rt_send_redirect(struct sk_buff *skb);
 | 
						|
 | 
						|
extern unsigned int		inet_addr_type(struct net *net, __be32 addr);
 | 
						|
extern unsigned int		inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr);
 | 
						|
extern void		ip_rt_multicast_event(struct in_device *);
 | 
						|
extern int		ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg);
 | 
						|
extern void		ip_rt_get_source(u8 *src, struct sk_buff *skb, struct rtable *rt);
 | 
						|
extern int		ip_rt_dump(struct sk_buff *skb,  struct netlink_callback *cb);
 | 
						|
 | 
						|
struct in_ifaddr;
 | 
						|
extern void fib_add_ifaddr(struct in_ifaddr *);
 | 
						|
extern void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *);
 | 
						|
 | 
						|
static inline void ip_rt_put(struct rtable * rt)
 | 
						|
{
 | 
						|
	if (rt)
 | 
						|
		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, bool can_sleep)
 | 
						|
{
 | 
						|
	__u8 flow_flags = 0;
 | 
						|
 | 
						|
	if (inet_sk(sk)->transparent)
 | 
						|
		flow_flags |= FLOWI_FLAG_ANYSRC;
 | 
						|
	if (can_sleep)
 | 
						|
		flow_flags |= FLOWI_FLAG_CAN_SLEEP;
 | 
						|
 | 
						|
	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, bool can_sleep)
 | 
						|
{
 | 
						|
	struct net *net = sock_net(sk);
 | 
						|
	struct rtable *rt;
 | 
						|
 | 
						|
	ip_route_connect_init(fl4, dst, src, tos, oif, protocol,
 | 
						|
			      sport, dport, sk, can_sleep);
 | 
						|
 | 
						|
	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 */
 |