Commit | Line | Data |
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1da177e4 LT |
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 | * IPv4 Forwarding Information Base: policy rules. | |
7 | * | |
1da177e4 | 8 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> |
6a31d2a9 | 9 | * Thomas Graf <tgraf@suug.ch> |
1da177e4 LT |
10 | * |
11 | * This program is free software; you can redistribute it and/or | |
12 | * modify it under the terms of the GNU General Public License | |
13 | * as published by the Free Software Foundation; either version | |
14 | * 2 of the License, or (at your option) any later version. | |
15 | * | |
16 | * Fixes: | |
6a31d2a9 | 17 | * Rani Assaf : local_rule cannot be deleted |
1da177e4 LT |
18 | * Marc Boucher : routing by fwmark |
19 | */ | |
20 | ||
1da177e4 LT |
21 | #include <linux/types.h> |
22 | #include <linux/kernel.h> | |
1da177e4 | 23 | #include <linux/netdevice.h> |
1da177e4 | 24 | #include <linux/netlink.h> |
e1ef4bf2 | 25 | #include <linux/inetdevice.h> |
1da177e4 | 26 | #include <linux/init.h> |
7b204afd RO |
27 | #include <linux/list.h> |
28 | #include <linux/rcupdate.h> | |
1da177e4 | 29 | #include <net/ip.h> |
1da177e4 LT |
30 | #include <net/route.h> |
31 | #include <net/tcp.h> | |
1da177e4 | 32 | #include <net/ip_fib.h> |
e1ef4bf2 | 33 | #include <net/fib_rules.h> |
1da177e4 | 34 | |
6a31d2a9 | 35 | struct fib4_rule { |
e1ef4bf2 TG |
36 | struct fib_rule common; |
37 | u8 dst_len; | |
38 | u8 src_len; | |
39 | u8 tos; | |
81f7bf6c AV |
40 | __be32 src; |
41 | __be32 srcmask; | |
42 | __be32 dst; | |
43 | __be32 dstmask; | |
1da177e4 | 44 | #ifdef CONFIG_NET_CLS_ROUTE |
e1ef4bf2 | 45 | u32 tclassid; |
1da177e4 | 46 | #endif |
1da177e4 LT |
47 | }; |
48 | ||
e1ef4bf2 TG |
49 | #ifdef CONFIG_NET_CLS_ROUTE |
50 | u32 fib_rules_tclass(struct fib_result *res) | |
51 | { | |
52 | return res->r ? ((struct fib4_rule *) res->r)->tclassid : 0; | |
53 | } | |
54 | #endif | |
7b204afd | 55 | |
da0e28cb | 56 | int fib_lookup(struct net *net, struct flowi *flp, struct fib_result *res) |
e1ef4bf2 TG |
57 | { |
58 | struct fib_lookup_arg arg = { | |
59 | .result = res, | |
ebc0ffae | 60 | .flags = FIB_LOOKUP_NOREF, |
e1ef4bf2 TG |
61 | }; |
62 | int err; | |
1da177e4 | 63 | |
da0e28cb | 64 | err = fib_rules_lookup(net->ipv4.rules_ops, flp, 0, &arg); |
e1ef4bf2 | 65 | res->r = arg.rule; |
a5cdc030 | 66 | |
e1ef4bf2 TG |
67 | return err; |
68 | } | |
69 | ||
8ce11e6a AB |
70 | static int fib4_rule_action(struct fib_rule *rule, struct flowi *flp, |
71 | int flags, struct fib_lookup_arg *arg) | |
1da177e4 | 72 | { |
e1ef4bf2 TG |
73 | int err = -EAGAIN; |
74 | struct fib_table *tbl; | |
75 | ||
76 | switch (rule->action) { | |
77 | case FR_ACT_TO_TBL: | |
78 | break; | |
79 | ||
80 | case FR_ACT_UNREACHABLE: | |
81 | err = -ENETUNREACH; | |
82 | goto errout; | |
83 | ||
84 | case FR_ACT_PROHIBIT: | |
85 | err = -EACCES; | |
86 | goto errout; | |
87 | ||
88 | case FR_ACT_BLACKHOLE: | |
89 | default: | |
90 | err = -EINVAL; | |
91 | goto errout; | |
1da177e4 | 92 | } |
e1ef4bf2 | 93 | |
6a31d2a9 ED |
94 | tbl = fib_get_table(rule->fr_net, rule->table); |
95 | if (!tbl) | |
e1ef4bf2 TG |
96 | goto errout; |
97 | ||
ebc0ffae | 98 | err = fib_table_lookup(tbl, flp, (struct fib_result *) arg->result, arg->flags); |
e1ef4bf2 TG |
99 | if (err > 0) |
100 | err = -EAGAIN; | |
101 | errout: | |
1da177e4 LT |
102 | return err; |
103 | } | |
104 | ||
e1ef4bf2 | 105 | |
e1ef4bf2 TG |
106 | static int fib4_rule_match(struct fib_rule *rule, struct flowi *fl, int flags) |
107 | { | |
108 | struct fib4_rule *r = (struct fib4_rule *) rule; | |
81f7bf6c AV |
109 | __be32 daddr = fl->fl4_dst; |
110 | __be32 saddr = fl->fl4_src; | |
e1ef4bf2 TG |
111 | |
112 | if (((saddr ^ r->src) & r->srcmask) || | |
113 | ((daddr ^ r->dst) & r->dstmask)) | |
114 | return 0; | |
115 | ||
116 | if (r->tos && (r->tos != fl->fl4_tos)) | |
117 | return 0; | |
118 | ||
e1ef4bf2 TG |
119 | return 1; |
120 | } | |
1da177e4 | 121 | |
8ad4942c | 122 | static struct fib_table *fib_empty_table(struct net *net) |
1da177e4 | 123 | { |
2dfe55b4 | 124 | u32 id; |
1da177e4 LT |
125 | |
126 | for (id = 1; id <= RT_TABLE_MAX; id++) | |
8ad4942c DL |
127 | if (fib_get_table(net, id) == NULL) |
128 | return fib_new_table(net, id); | |
1da177e4 LT |
129 | return NULL; |
130 | } | |
131 | ||
ef7c79ed | 132 | static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = { |
1f6c9557 | 133 | FRA_GENERIC_POLICY, |
e1ef4bf2 TG |
134 | [FRA_FLOW] = { .type = NLA_U32 }, |
135 | }; | |
7b204afd | 136 | |
e1ef4bf2 | 137 | static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb, |
8b3521ee | 138 | struct fib_rule_hdr *frh, |
e1ef4bf2 | 139 | struct nlattr **tb) |
1da177e4 | 140 | { |
3b1e0a65 | 141 | struct net *net = sock_net(skb->sk); |
e1ef4bf2 TG |
142 | int err = -EINVAL; |
143 | struct fib4_rule *rule4 = (struct fib4_rule *) rule; | |
1da177e4 | 144 | |
e1701c68 | 145 | if (frh->tos & ~IPTOS_TOS_MASK) |
e1ef4bf2 | 146 | goto errout; |
7b204afd | 147 | |
e1ef4bf2 TG |
148 | if (rule->table == RT_TABLE_UNSPEC) { |
149 | if (rule->action == FR_ACT_TO_TBL) { | |
150 | struct fib_table *table; | |
1da177e4 | 151 | |
e4e4971c | 152 | table = fib_empty_table(net); |
e1ef4bf2 TG |
153 | if (table == NULL) { |
154 | err = -ENOBUFS; | |
155 | goto errout; | |
156 | } | |
1da177e4 | 157 | |
e1ef4bf2 | 158 | rule->table = table->tb_id; |
1da177e4 LT |
159 | } |
160 | } | |
161 | ||
e1701c68 | 162 | if (frh->src_len) |
45d60b9e | 163 | rule4->src = nla_get_be32(tb[FRA_SRC]); |
7b204afd | 164 | |
e1701c68 | 165 | if (frh->dst_len) |
45d60b9e | 166 | rule4->dst = nla_get_be32(tb[FRA_DST]); |
7b204afd | 167 | |
1da177e4 | 168 | #ifdef CONFIG_NET_CLS_ROUTE |
e1ef4bf2 TG |
169 | if (tb[FRA_FLOW]) |
170 | rule4->tclassid = nla_get_u32(tb[FRA_FLOW]); | |
1da177e4 LT |
171 | #endif |
172 | ||
e1ef4bf2 TG |
173 | rule4->src_len = frh->src_len; |
174 | rule4->srcmask = inet_make_mask(rule4->src_len); | |
175 | rule4->dst_len = frh->dst_len; | |
176 | rule4->dstmask = inet_make_mask(rule4->dst_len); | |
177 | rule4->tos = frh->tos; | |
7b204afd | 178 | |
e1ef4bf2 TG |
179 | err = 0; |
180 | errout: | |
181 | return err; | |
1da177e4 LT |
182 | } |
183 | ||
e1ef4bf2 TG |
184 | static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, |
185 | struct nlattr **tb) | |
1da177e4 | 186 | { |
e1ef4bf2 | 187 | struct fib4_rule *rule4 = (struct fib4_rule *) rule; |
1da177e4 | 188 | |
e1ef4bf2 TG |
189 | if (frh->src_len && (rule4->src_len != frh->src_len)) |
190 | return 0; | |
1da177e4 | 191 | |
e1ef4bf2 TG |
192 | if (frh->dst_len && (rule4->dst_len != frh->dst_len)) |
193 | return 0; | |
7b204afd | 194 | |
e1ef4bf2 TG |
195 | if (frh->tos && (rule4->tos != frh->tos)) |
196 | return 0; | |
7b204afd | 197 | |
e1ef4bf2 TG |
198 | #ifdef CONFIG_NET_CLS_ROUTE |
199 | if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW]))) | |
200 | return 0; | |
201 | #endif | |
1da177e4 | 202 | |
e1701c68 | 203 | if (frh->src_len && (rule4->src != nla_get_be32(tb[FRA_SRC]))) |
e1ef4bf2 | 204 | return 0; |
1da177e4 | 205 | |
e1701c68 | 206 | if (frh->dst_len && (rule4->dst != nla_get_be32(tb[FRA_DST]))) |
e1ef4bf2 | 207 | return 0; |
1da177e4 | 208 | |
e1ef4bf2 | 209 | return 1; |
1da177e4 LT |
210 | } |
211 | ||
e1ef4bf2 | 212 | static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb, |
04af8cf6 | 213 | struct fib_rule_hdr *frh) |
e1ef4bf2 TG |
214 | { |
215 | struct fib4_rule *rule4 = (struct fib4_rule *) rule; | |
1da177e4 | 216 | |
e1ef4bf2 TG |
217 | frh->dst_len = rule4->dst_len; |
218 | frh->src_len = rule4->src_len; | |
219 | frh->tos = rule4->tos; | |
1da177e4 | 220 | |
e1ef4bf2 | 221 | if (rule4->dst_len) |
45d60b9e | 222 | NLA_PUT_BE32(skb, FRA_DST, rule4->dst); |
e1ef4bf2 TG |
223 | |
224 | if (rule4->src_len) | |
45d60b9e | 225 | NLA_PUT_BE32(skb, FRA_SRC, rule4->src); |
e1ef4bf2 | 226 | |
1da177e4 | 227 | #ifdef CONFIG_NET_CLS_ROUTE |
e1ef4bf2 TG |
228 | if (rule4->tclassid) |
229 | NLA_PUT_U32(skb, FRA_FLOW, rule4->tclassid); | |
1da177e4 | 230 | #endif |
e1ef4bf2 | 231 | return 0; |
1da177e4 | 232 | |
e1ef4bf2 TG |
233 | nla_put_failure: |
234 | return -ENOBUFS; | |
1da177e4 LT |
235 | } |
236 | ||
339bf98f TG |
237 | static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule) |
238 | { | |
239 | return nla_total_size(4) /* dst */ | |
240 | + nla_total_size(4) /* src */ | |
241 | + nla_total_size(4); /* flow */ | |
242 | } | |
243 | ||
ae299fc0 | 244 | static void fib4_rule_flush_cache(struct fib_rules_ops *ops) |
73417f61 | 245 | { |
ae299fc0 | 246 | rt_cache_flush(ops->fro_net, -1); |
73417f61 TG |
247 | } |
248 | ||
3d0c9c4e | 249 | static const struct fib_rules_ops __net_initdata fib4_rules_ops_template = { |
25239cee | 250 | .family = AF_INET, |
e1ef4bf2 | 251 | .rule_size = sizeof(struct fib4_rule), |
e1701c68 | 252 | .addr_size = sizeof(u32), |
e1ef4bf2 TG |
253 | .action = fib4_rule_action, |
254 | .match = fib4_rule_match, | |
255 | .configure = fib4_rule_configure, | |
256 | .compare = fib4_rule_compare, | |
257 | .fill = fib4_rule_fill, | |
d8a566be | 258 | .default_pref = fib_default_rule_pref, |
339bf98f | 259 | .nlmsg_payload = fib4_rule_nlmsg_payload, |
73417f61 | 260 | .flush_cache = fib4_rule_flush_cache, |
e1ef4bf2 TG |
261 | .nlgroup = RTNLGRP_IPV4_RULE, |
262 | .policy = fib4_rule_policy, | |
e1ef4bf2 TG |
263 | .owner = THIS_MODULE, |
264 | }; | |
265 | ||
e4e4971c | 266 | static int fib_default_rules_init(struct fib_rules_ops *ops) |
1da177e4 | 267 | { |
2994c638 DL |
268 | int err; |
269 | ||
5adef180 | 270 | err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0); |
2994c638 DL |
271 | if (err < 0) |
272 | return err; | |
e4e4971c | 273 | err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0); |
2994c638 DL |
274 | if (err < 0) |
275 | return err; | |
e4e4971c | 276 | err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0); |
2994c638 DL |
277 | if (err < 0) |
278 | return err; | |
279 | return 0; | |
280 | } | |
1da177e4 | 281 | |
7b1a74fd | 282 | int __net_init fib4_rules_init(struct net *net) |
2994c638 | 283 | { |
dbb50165 | 284 | int err; |
e4e4971c DL |
285 | struct fib_rules_ops *ops; |
286 | ||
e9c5158a EB |
287 | ops = fib_rules_register(&fib4_rules_ops_template, net); |
288 | if (IS_ERR(ops)) | |
289 | return PTR_ERR(ops); | |
dbb50165 | 290 | |
e4e4971c | 291 | err = fib_default_rules_init(ops); |
dbb50165 DL |
292 | if (err < 0) |
293 | goto fail; | |
e4e4971c | 294 | net->ipv4.rules_ops = ops; |
dbb50165 DL |
295 | return 0; |
296 | ||
297 | fail: | |
298 | /* also cleans all rules already added */ | |
9e3a5487 | 299 | fib_rules_unregister(ops); |
dbb50165 | 300 | return err; |
1da177e4 | 301 | } |
7b1a74fd DL |
302 | |
303 | void __net_exit fib4_rules_exit(struct net *net) | |
304 | { | |
9e3a5487 | 305 | fib_rules_unregister(net->ipv4.rules_ops); |
7b1a74fd | 306 | } |