aboutsummaryrefslogtreecommitdiff
path: root/include/net/route.h
blob: b1c0d5b564c2c1936455086cbf37dbbc761de0dd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
/*
 * 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/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 inet_peer;
struct fib_info;
struct rtable {
	struct dst_entry	dst;

	/* Lookup key. */
	__be32			rt_key_dst;
	__be32			rt_key_src;

	int			rt_genid;
	unsigned		rt_flags;
	__u16			rt_type;
	__u8			rt_key_tos;

	__be32			rt_dst;	/* Path destination	*/
	__be32			rt_src;	/* Path source		*/
	int			rt_route_iif;
	int			rt_iif;
	int			rt_oif;
	__u32			rt_mark;

	/* Info on neighbour */
	__be32			rt_gateway;

	/* Miscellaneous cached information */
	__be32			rt_spec_dst; /* RFC1122 specific destination */
	u32			rt_peer_genid;
	struct inet_peer	*peer; /* long-living peer info */
	struct fib_info		*fi; /* for client ref to shared metrics */
};

static inline bool rt_is_input_route(const struct rtable *rt)
{
	return rt->rt_route_iif != 0;
}

static inline bool rt_is_output_route(const struct rtable *rt)
{
	return rt->rt_route_iif == 0;
}

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		ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw,
				       __be32 src, struct net_device *dev);
extern void		rt_cache_flush(struct net *net, int how);
extern void		rt_cache_flush_batch(struct net *net);
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,
		.daddr = daddr,
		.saddr = saddr,
		.flowi4_tos = tos,
	};
	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_common(struct sk_buff *skb, __be32 dst, __be32 src,
				 u8 tos, struct net_device *devin, bool noref);

static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src,
				 u8 tos, struct net_device *devin)
{
	return ip_route_input_common(skb, dst, src, tos, devin, false);
}

static inline int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src,
				       u8 tos, struct net_device *devin)
{
	return ip_route_input_common(skb, dst, src, tos, devin, true);
}

extern unsigned short	ip_rt_frag_needed(struct net *net, const struct iphdr *iph,
					  unsigned short new_mtu, struct net_device *dev);
extern void		ip_rt_send_redirect(struct sk_buff *skb);

extern unsigned		inet_addr_type(struct net *net, __be32 addr);
extern unsigned		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 (protocol == IPPROTO_TCP)
		flow_flags |= FLOWI_FLAG_PRECOW_METRICS;
	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;
}

extern void rt_bind_peer(struct rtable *rt, __be32 daddr, int create);

static inline struct inet_peer *rt_get_peer(struct rtable *rt, __be32 daddr)
{
	if (rt->peer)
		return rt->peer;

	rt_bind_peer(rt, daddr, 0);
	return rt->peer;
}

static inline int inet_iif(const struct sk_buff *skb)
{
	return skb_rtable(skb)->rt_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 */