Merge branch 'for-2.6.19' of git://brick.kernel.dk/data/git/linux-2.6-block
[linux-2.6] / net / ipv6 / fib6_rules.c
1 /*
2  * net/ipv6/fib6_rules.c        IPv6 Routing Policy Rules
3  *
4  * Copyright (C)2003-2006 Helsinki University of Technology
5  * Copyright (C)2003-2006 USAGI/WIDE Project
6  *
7  *      This program is free software; you can redistribute it and/or
8  *      modify it under the terms of the GNU General Public License as
9  *      published by the Free Software Foundation, version 2.
10  *
11  * Authors
12  *      Thomas Graf             <tgraf@suug.ch>
13  *      Ville Nuorvala          <vnuorval@tcs.hut.fi>
14  */
15
16 #include <linux/netdevice.h>
17
18 #include <net/fib_rules.h>
19 #include <net/ipv6.h>
20 #include <net/ip6_route.h>
21 #include <net/netlink.h>
22
23 struct fib6_rule
24 {
25         struct fib_rule         common;
26         struct rt6key           src;
27         struct rt6key           dst;
28 #ifdef CONFIG_IPV6_ROUTE_FWMARK
29         u32                     fwmark;
30         u32                     fwmask;
31 #endif
32         u8                      tclass;
33 };
34
35 static struct fib_rules_ops fib6_rules_ops;
36
37 static struct fib6_rule main_rule = {
38         .common = {
39                 .refcnt =       ATOMIC_INIT(2),
40                 .pref =         0x7FFE,
41                 .action =       FR_ACT_TO_TBL,
42                 .table =        RT6_TABLE_MAIN,
43         },
44 };
45
46 static struct fib6_rule local_rule = {
47         .common = {
48                 .refcnt =       ATOMIC_INIT(2),
49                 .pref =         0,
50                 .action =       FR_ACT_TO_TBL,
51                 .table =        RT6_TABLE_LOCAL,
52                 .flags =        FIB_RULE_PERMANENT,
53         },
54 };
55
56 static LIST_HEAD(fib6_rules);
57
58 struct dst_entry *fib6_rule_lookup(struct flowi *fl, int flags,
59                                    pol_lookup_t lookup)
60 {
61         struct fib_lookup_arg arg = {
62                 .lookup_ptr = lookup,
63         };
64
65         fib_rules_lookup(&fib6_rules_ops, fl, flags, &arg);
66         if (arg.rule)
67                 fib_rule_put(arg.rule);
68
69         if (arg.result)
70                 return (struct dst_entry *) arg.result;
71
72         dst_hold(&ip6_null_entry.u.dst);
73         return &ip6_null_entry.u.dst;
74 }
75
76 static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
77                             int flags, struct fib_lookup_arg *arg)
78 {
79         struct rt6_info *rt = NULL;
80         struct fib6_table *table;
81         pol_lookup_t lookup = arg->lookup_ptr;
82
83         switch (rule->action) {
84         case FR_ACT_TO_TBL:
85                 break;
86         case FR_ACT_UNREACHABLE:
87                 rt = &ip6_null_entry;
88                 goto discard_pkt;
89         default:
90         case FR_ACT_BLACKHOLE:
91                 rt = &ip6_blk_hole_entry;
92                 goto discard_pkt;
93         case FR_ACT_PROHIBIT:
94                 rt = &ip6_prohibit_entry;
95                 goto discard_pkt;
96         }
97
98         table = fib6_get_table(rule->table);
99         if (table)
100                 rt = lookup(table, flp, flags);
101
102         if (rt != &ip6_null_entry)
103                 goto out;
104         dst_release(&rt->u.dst);
105         rt = NULL;
106         goto out;
107
108 discard_pkt:
109         dst_hold(&rt->u.dst);
110 out:
111         arg->result = rt;
112         return rt == NULL ? -EAGAIN : 0;
113 }
114
115
116 static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
117 {
118         struct fib6_rule *r = (struct fib6_rule *) rule;
119
120         if (!ipv6_prefix_equal(&fl->fl6_dst, &r->dst.addr, r->dst.plen))
121                 return 0;
122
123         if ((flags & RT6_LOOKUP_F_HAS_SADDR) &&
124             !ipv6_prefix_equal(&fl->fl6_src, &r->src.addr, r->src.plen))
125                 return 0;
126
127         if (r->tclass && r->tclass != ((ntohl(fl->fl6_flowlabel) >> 20) & 0xff))
128                 return 0;
129
130 #ifdef CONFIG_IPV6_ROUTE_FWMARK
131         if ((r->fwmark ^ fl->fl6_fwmark) & r->fwmask)
132                 return 0;
133 #endif
134
135         return 1;
136 }
137
138 static struct nla_policy fib6_rule_policy[FRA_MAX+1] __read_mostly = {
139         [FRA_IFNAME]    = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
140         [FRA_PRIORITY]  = { .type = NLA_U32 },
141         [FRA_SRC]       = { .len = sizeof(struct in6_addr) },
142         [FRA_DST]       = { .len = sizeof(struct in6_addr) },
143         [FRA_FWMARK]    = { .type = NLA_U32 },
144         [FRA_FWMASK]    = { .type = NLA_U32 },
145         [FRA_TABLE]     = { .type = NLA_U32 },
146 };
147
148 static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
149                                struct nlmsghdr *nlh, struct fib_rule_hdr *frh,
150                                struct nlattr **tb)
151 {
152         int err = -EINVAL;
153         struct fib6_rule *rule6 = (struct fib6_rule *) rule;
154
155         if (frh->src_len > 128 || frh->dst_len > 128 ||
156             (frh->tos & ~IPV6_FLOWINFO_MASK))
157                 goto errout;
158
159         if (rule->action == FR_ACT_TO_TBL) {
160                 if (rule->table == RT6_TABLE_UNSPEC)
161                         goto errout;
162
163                 if (fib6_new_table(rule->table) == NULL) {
164                         err = -ENOBUFS;
165                         goto errout;
166                 }
167         }
168
169         if (tb[FRA_SRC])
170                 nla_memcpy(&rule6->src.addr, tb[FRA_SRC],
171                            sizeof(struct in6_addr));
172
173         if (tb[FRA_DST])
174                 nla_memcpy(&rule6->dst.addr, tb[FRA_DST],
175                            sizeof(struct in6_addr));
176
177 #ifdef CONFIG_IPV6_ROUTE_FWMARK
178         if (tb[FRA_FWMARK]) {
179                 rule6->fwmark = nla_get_u32(tb[FRA_FWMARK]);
180                 if (rule6->fwmark) {
181                         /*
182                          * if the mark value is non-zero,
183                          * all bits are compared by default
184                          * unless a mask is explicitly specified.
185                          */
186                         rule6->fwmask = 0xFFFFFFFF;
187                 }
188         }
189
190         if (tb[FRA_FWMASK])
191                 rule6->fwmask = nla_get_u32(tb[FRA_FWMASK]);
192 #endif
193
194         rule6->src.plen = frh->src_len;
195         rule6->dst.plen = frh->dst_len;
196         rule6->tclass = frh->tos;
197
198         err = 0;
199 errout:
200         return err;
201 }
202
203 static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
204                              struct nlattr **tb)
205 {
206         struct fib6_rule *rule6 = (struct fib6_rule *) rule;
207
208         if (frh->src_len && (rule6->src.plen != frh->src_len))
209                 return 0;
210
211         if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
212                 return 0;
213
214         if (frh->tos && (rule6->tclass != frh->tos))
215                 return 0;
216
217         if (tb[FRA_SRC] &&
218             nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
219                 return 0;
220
221         if (tb[FRA_DST] &&
222             nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
223                 return 0;
224
225 #ifdef CONFIG_IPV6_ROUTE_FWMARK
226         if (tb[FRA_FWMARK] && (rule6->fwmark != nla_get_u32(tb[FRA_FWMARK])))
227                 return 0;
228
229         if (tb[FRA_FWMASK] && (rule6->fwmask != nla_get_u32(tb[FRA_FWMASK])))
230                 return 0;
231 #endif
232
233         return 1;
234 }
235
236 static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
237                           struct nlmsghdr *nlh, struct fib_rule_hdr *frh)
238 {
239         struct fib6_rule *rule6 = (struct fib6_rule *) rule;
240
241         frh->family = AF_INET6;
242         frh->dst_len = rule6->dst.plen;
243         frh->src_len = rule6->src.plen;
244         frh->tos = rule6->tclass;
245
246         if (rule6->dst.plen)
247                 NLA_PUT(skb, FRA_DST, sizeof(struct in6_addr),
248                         &rule6->dst.addr);
249
250         if (rule6->src.plen)
251                 NLA_PUT(skb, FRA_SRC, sizeof(struct in6_addr),
252                         &rule6->src.addr);
253
254 #ifdef CONFIG_IPV6_ROUTE_FWMARK
255         if (rule6->fwmark)
256                 NLA_PUT_U32(skb, FRA_FWMARK, rule6->fwmark);
257
258         if (rule6->fwmask || rule6->fwmark)
259                 NLA_PUT_U32(skb, FRA_FWMASK, rule6->fwmask);
260 #endif
261
262         return 0;
263
264 nla_put_failure:
265         return -ENOBUFS;
266 }
267
268 int fib6_rules_dump(struct sk_buff *skb, struct netlink_callback *cb)
269 {
270         return fib_rules_dump(skb, cb, AF_INET6);
271 }
272
273 static u32 fib6_rule_default_pref(void)
274 {
275         return 0x3FFF;
276 }
277
278 static struct fib_rules_ops fib6_rules_ops = {
279         .family                 = AF_INET6,
280         .rule_size              = sizeof(struct fib6_rule),
281         .action                 = fib6_rule_action,
282         .match                  = fib6_rule_match,
283         .configure              = fib6_rule_configure,
284         .compare                = fib6_rule_compare,
285         .fill                   = fib6_rule_fill,
286         .default_pref           = fib6_rule_default_pref,
287         .nlgroup                = RTNLGRP_IPV6_RULE,
288         .policy                 = fib6_rule_policy,
289         .rules_list             = &fib6_rules,
290         .owner                  = THIS_MODULE,
291 };
292
293 void __init fib6_rules_init(void)
294 {
295         list_add_tail(&local_rule.common.list, &fib6_rules);
296         list_add_tail(&main_rule.common.list, &fib6_rules);
297
298         fib_rules_register(&fib6_rules_ops);
299 }
300
301 void fib6_rules_cleanup(void)
302 {
303         fib_rules_unregister(&fib6_rules_ops);
304 }