1/*
2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
3 *		operating system.  INET  is implemented using the  BSD Socket
4 *		interface as the means of communication with the user level.
5 *
6 *		Definitions for the Forwarding Information Base.
7 *
8 * Authors:	A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
9 *
10 *		This program is free software; you can redistribute it and/or
11 *		modify it under the terms of the GNU General Public License
12 *		as published by the Free Software Foundation; either version
13 *		2 of the License, or (at your option) any later version.
14 */
15
16#ifndef _NET_IP_FIB_H
17#define _NET_IP_FIB_H
18
19#include <net/flow.h>
20#include <linux/seq_file.h>
21#include <net/fib_rules.h>
22
23struct fib_config {
24	u8			fc_dst_len;
25	u8			fc_tos;
26	u8			fc_protocol;
27	u8			fc_scope;
28	u8			fc_type;
29	/* 3 bytes unused */
30	u32			fc_table;
31	__be32			fc_dst;
32	__be32			fc_gw;
33	int			fc_oif;
34	u32			fc_flags;
35	u32			fc_priority;
36	__be32			fc_prefsrc;
37	struct nlattr		*fc_mx;
38	struct rtnexthop	*fc_mp;
39	int			fc_mx_len;
40	int			fc_mp_len;
41	u32			fc_flow;
42	u32			fc_mp_alg;
43	u32			fc_nlflags;
44	struct nl_info		fc_nlinfo;
45 };
46
47struct fib_info;
48
49struct fib_nh {
50	struct net_device	*nh_dev;
51	struct hlist_node	nh_hash;
52	struct fib_info		*nh_parent;
53	unsigned		nh_flags;
54	unsigned char		nh_scope;
55#ifdef CONFIG_IP_ROUTE_MULTIPATH
56	int			nh_weight;
57	int			nh_power;
58#endif
59#ifdef CONFIG_NET_CLS_ROUTE
60	__u32			nh_tclassid;
61#endif
62	int			nh_oif;
63	__be32			nh_gw;
64};
65
66/*
67 * This structure contains data shared by many of routes.
68 */
69
70struct fib_info {
71	struct hlist_node	fib_hash;
72	struct hlist_node	fib_lhash;
73	int			fib_treeref;
74	atomic_t		fib_clntref;
75	int			fib_dead;
76	unsigned		fib_flags;
77	int			fib_protocol;
78	__be32			fib_prefsrc;
79	u32			fib_priority;
80	u32			fib_metrics[RTAX_MAX];
81#define fib_mtu fib_metrics[RTAX_MTU-1]
82#define fib_window fib_metrics[RTAX_WINDOW-1]
83#define fib_rtt fib_metrics[RTAX_RTT-1]
84#define fib_advmss fib_metrics[RTAX_ADVMSS-1]
85	int			fib_nhs;
86#ifdef CONFIG_IP_ROUTE_MULTIPATH
87	int			fib_power;
88#endif
89#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
90	u32			fib_mp_alg;
91#endif
92	struct fib_nh		fib_nh[0];
93#define fib_dev		fib_nh[0].nh_dev
94};
95
96
97#ifdef CONFIG_IP_MULTIPLE_TABLES
98struct fib_rule;
99#endif
100
101struct fib_result {
102	unsigned char	prefixlen;
103	unsigned char	nh_sel;
104	unsigned char	type;
105	unsigned char	scope;
106#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
107	__be32          network;
108	__be32          netmask;
109#endif
110	struct fib_info *fi;
111#ifdef CONFIG_IP_MULTIPLE_TABLES
112	struct fib_rule	*r;
113#endif
114};
115
116struct fib_result_nl {
117	__be32		fl_addr;   /* To be looked up*/
118	u32		fl_mark;
119	unsigned char	fl_tos;
120	unsigned char   fl_scope;
121	unsigned char   tb_id_in;
122
123	unsigned char   tb_id;      /* Results */
124	unsigned char	prefixlen;
125	unsigned char	nh_sel;
126	unsigned char	type;
127	unsigned char	scope;
128	int             err;
129};
130
131#ifdef CONFIG_IP_ROUTE_MULTIPATH
132
133#define FIB_RES_NH(res)		((res).fi->fib_nh[(res).nh_sel])
134#define FIB_RES_RESET(res)	((res).nh_sel = 0)
135
136#else /* CONFIG_IP_ROUTE_MULTIPATH */
137
138#define FIB_RES_NH(res)		((res).fi->fib_nh[0])
139#define FIB_RES_RESET(res)
140
141#endif /* CONFIG_IP_ROUTE_MULTIPATH */
142
143#define FIB_RES_PREFSRC(res)		((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res))
144#define FIB_RES_GW(res)			(FIB_RES_NH(res).nh_gw)
145#define FIB_RES_DEV(res)		(FIB_RES_NH(res).nh_dev)
146#define FIB_RES_OIF(res)		(FIB_RES_NH(res).nh_oif)
147
148#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
149#define FIB_RES_NETWORK(res)		((res).network)
150#define FIB_RES_NETMASK(res)	        ((res).netmask)
151#else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */
152#define FIB_RES_NETWORK(res)		(0)
153#define FIB_RES_NETMASK(res)	        (0)
154#endif /* CONFIG_IP_ROUTE_MULTIPATH_WRANDOM */
155
156struct fib_table {
157	struct hlist_node tb_hlist;
158	u32		tb_id;
159	unsigned	tb_stamp;
160	int		(*tb_lookup)(struct fib_table *tb, const struct flowi *flp, struct fib_result *res);
161	int		(*tb_insert)(struct fib_table *, struct fib_config *);
162	int		(*tb_delete)(struct fib_table *, struct fib_config *);
163	int		(*tb_dump)(struct fib_table *table, struct sk_buff *skb,
164				     struct netlink_callback *cb);
165	int		(*tb_flush)(struct fib_table *table);
166	void		(*tb_select_default)(struct fib_table *table,
167					     const struct flowi *flp, struct fib_result *res);
168
169	unsigned char	tb_data[0];
170};
171
172#ifndef CONFIG_IP_MULTIPLE_TABLES
173
174extern struct fib_table *ip_fib_local_table;
175extern struct fib_table *ip_fib_main_table;
176
177static inline struct fib_table *fib_get_table(u32 id)
178{
179	if (id != RT_TABLE_LOCAL)
180		return ip_fib_main_table;
181	return ip_fib_local_table;
182}
183
184static inline struct fib_table *fib_new_table(u32 id)
185{
186	return fib_get_table(id);
187}
188
189static inline int fib_lookup(const struct flowi *flp, struct fib_result *res)
190{
191	if (ip_fib_local_table->tb_lookup(ip_fib_local_table, flp, res) &&
192	    ip_fib_main_table->tb_lookup(ip_fib_main_table, flp, res))
193		return -ENETUNREACH;
194	return 0;
195}
196
197static inline void fib_select_default(const struct flowi *flp, struct fib_result *res)
198{
199	if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
200		ip_fib_main_table->tb_select_default(ip_fib_main_table, flp, res);
201}
202
203#else /* CONFIG_IP_MULTIPLE_TABLES */
204#define ip_fib_local_table fib_get_table(RT_TABLE_LOCAL)
205#define ip_fib_main_table fib_get_table(RT_TABLE_MAIN)
206
207extern int fib_lookup(struct flowi *flp, struct fib_result *res);
208
209extern struct fib_table *fib_new_table(u32 id);
210extern struct fib_table *fib_get_table(u32 id);
211extern void fib_select_default(const struct flowi *flp, struct fib_result *res);
212
213#endif /* CONFIG_IP_MULTIPLE_TABLES */
214
215/* Exported by fib_frontend.c */
216extern const struct nla_policy rtm_ipv4_policy[];
217extern void		ip_fib_init(void);
218extern int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
219			       struct net_device *dev, __be32 *spec_dst, u32 *itag);
220extern void fib_select_multipath(const struct flowi *flp, struct fib_result *res);
221
222struct rtentry;
223
224/* Exported by fib_semantics.c */
225extern int ip_fib_check_default(__be32 gw, struct net_device *dev);
226extern int fib_sync_down(__be32 local, struct net_device *dev, int force);
227extern int fib_sync_up(struct net_device *dev);
228extern __be32  __fib_res_prefsrc(struct fib_result *res);
229
230/* Exported by fib_hash.c */
231extern struct fib_table *fib_hash_init(u32 id);
232
233#ifdef CONFIG_IP_MULTIPLE_TABLES
234extern void __init fib4_rules_init(void);
235
236#ifdef CONFIG_NET_CLS_ROUTE
237extern u32 fib_rules_tclass(struct fib_result *res);
238#endif
239
240#endif
241
242static inline void fib_combine_itag(u32 *itag, struct fib_result *res)
243{
244#ifdef CONFIG_NET_CLS_ROUTE
245#ifdef CONFIG_IP_MULTIPLE_TABLES
246	u32 rtag;
247#endif
248	*itag = FIB_RES_NH(*res).nh_tclassid<<16;
249#ifdef CONFIG_IP_MULTIPLE_TABLES
250	rtag = fib_rules_tclass(res);
251	if (*itag == 0)
252		*itag = (rtag<<16);
253	*itag |= (rtag>>16);
254#endif
255#endif
256}
257
258extern void free_fib_info(struct fib_info *fi);
259
260static inline void fib_info_put(struct fib_info *fi)
261{
262	if (atomic_dec_and_test(&fi->fib_clntref))
263		free_fib_info(fi);
264}
265
266static inline void fib_res_put(struct fib_result *res)
267{
268	if (res->fi)
269		fib_info_put(res->fi);
270#ifdef CONFIG_IP_MULTIPLE_TABLES
271	if (res->r)
272		fib_rule_put(res->r);
273#endif
274}
275
276#ifdef CONFIG_PROC_FS
277extern int  fib_proc_init(void);
278extern void fib_proc_exit(void);
279#endif
280
281#endif  /* _NET_FIB_H */
282