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16#include <linux/netdevice.h>
17
18#include <net/fib_rules.h>
19#include <net/ipv6.h>
20#include <net/addrconf.h>
21#include <net/ip6_route.h>
22#include <net/netlink.h>
23
24struct fib6_rule
25{
26 struct fib_rule common;
27 struct rt6key src;
28 struct rt6key dst;
29 u8 tclass;
30};
31
32struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi *fl,
33 int flags, pol_lookup_t lookup)
34{
35 struct fib_lookup_arg arg = {
36 .lookup_ptr = lookup,
37 };
38
39 fib_rules_lookup(net->ipv6.fib6_rules_ops, fl, flags, &arg);
40 if (arg.rule)
41 fib_rule_put(arg.rule);
42
43 if (arg.result)
44 return arg.result;
45
46 dst_hold(&net->ipv6.ip6_null_entry->u.dst);
47 return &net->ipv6.ip6_null_entry->u.dst;
48}
49
50static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
51 int flags, struct fib_lookup_arg *arg)
52{
53 struct rt6_info *rt = NULL;
54 struct fib6_table *table;
55 struct net *net = rule->fr_net;
56 pol_lookup_t lookup = arg->lookup_ptr;
57
58 switch (rule->action) {
59 case FR_ACT_TO_TBL:
60 break;
61 case FR_ACT_UNREACHABLE:
62 rt = net->ipv6.ip6_null_entry;
63 goto discard_pkt;
64 default:
65 case FR_ACT_BLACKHOLE:
66 rt = net->ipv6.ip6_blk_hole_entry;
67 goto discard_pkt;
68 case FR_ACT_PROHIBIT:
69 rt = net->ipv6.ip6_prohibit_entry;
70 goto discard_pkt;
71 }
72
73 table = fib6_get_table(net, rule->table);
74 if (table)
75 rt = lookup(net, table, flp, flags);
76
77 if (rt != net->ipv6.ip6_null_entry) {
78 struct fib6_rule *r = (struct fib6_rule *)rule;
79
80
81
82
83
84 if ((rule->flags & FIB_RULE_FIND_SADDR) &&
85 r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
86 struct in6_addr saddr;
87 unsigned int srcprefs = 0;
88
89 if (flags & RT6_LOOKUP_F_SRCPREF_TMP)
90 srcprefs |= IPV6_PREFER_SRC_TMP;
91 if (flags & RT6_LOOKUP_F_SRCPREF_PUBLIC)
92 srcprefs |= IPV6_PREFER_SRC_PUBLIC;
93 if (flags & RT6_LOOKUP_F_SRCPREF_COA)
94 srcprefs |= IPV6_PREFER_SRC_COA;
95
96 if (ipv6_dev_get_saddr(net,
97 ip6_dst_idev(&rt->u.dst)->dev,
98 &flp->fl6_dst, srcprefs,
99 &saddr))
100 goto again;
101 if (!ipv6_prefix_equal(&saddr, &r->src.addr,
102 r->src.plen))
103 goto again;
104 ipv6_addr_copy(&flp->fl6_src, &saddr);
105 }
106 goto out;
107 }
108again:
109 dst_release(&rt->u.dst);
110 rt = NULL;
111 goto out;
112
113discard_pkt:
114 dst_hold(&rt->u.dst);
115out:
116 arg->result = rt;
117 return rt == NULL ? -EAGAIN : 0;
118}
119
120
121static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
122{
123 struct fib6_rule *r = (struct fib6_rule *) rule;
124
125 if (r->dst.plen &&
126 !ipv6_prefix_equal(&fl->fl6_dst, &r->dst.addr, r->dst.plen))
127 return 0;
128
129
130
131
132
133
134 if (r->src.plen) {
135 if (flags & RT6_LOOKUP_F_HAS_SADDR) {
136 if (!ipv6_prefix_equal(&fl->fl6_src, &r->src.addr,
137 r->src.plen))
138 return 0;
139 } else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
140 return 0;
141 }
142
143 if (r->tclass && r->tclass != ((ntohl(fl->fl6_flowlabel) >> 20) & 0xff))
144 return 0;
145
146 return 1;
147}
148
149static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
150 FRA_GENERIC_POLICY,
151};
152
153static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
154 struct fib_rule_hdr *frh,
155 struct nlattr **tb)
156{
157 int err = -EINVAL;
158 struct net *net = sock_net(skb->sk);
159 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
160
161 if (rule->action == FR_ACT_TO_TBL) {
162 if (rule->table == RT6_TABLE_UNSPEC)
163 goto errout;
164
165 if (fib6_new_table(net, rule->table) == NULL) {
166 err = -ENOBUFS;
167 goto errout;
168 }
169 }
170
171 if (frh->src_len)
172 nla_memcpy(&rule6->src.addr, tb[FRA_SRC],
173 sizeof(struct in6_addr));
174
175 if (frh->dst_len)
176 nla_memcpy(&rule6->dst.addr, tb[FRA_DST],
177 sizeof(struct in6_addr));
178
179 rule6->src.plen = frh->src_len;
180 rule6->dst.plen = frh->dst_len;
181 rule6->tclass = frh->tos;
182
183 err = 0;
184errout:
185 return err;
186}
187
188static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
189 struct nlattr **tb)
190{
191 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
192
193 if (frh->src_len && (rule6->src.plen != frh->src_len))
194 return 0;
195
196 if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
197 return 0;
198
199 if (frh->tos && (rule6->tclass != frh->tos))
200 return 0;
201
202 if (frh->src_len &&
203 nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
204 return 0;
205
206 if (frh->dst_len &&
207 nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
208 return 0;
209
210 return 1;
211}
212
213static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
214 struct fib_rule_hdr *frh)
215{
216 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
217
218 frh->family = AF_INET6;
219 frh->dst_len = rule6->dst.plen;
220 frh->src_len = rule6->src.plen;
221 frh->tos = rule6->tclass;
222
223 if (rule6->dst.plen)
224 NLA_PUT(skb, FRA_DST, sizeof(struct in6_addr),
225 &rule6->dst.addr);
226
227 if (rule6->src.plen)
228 NLA_PUT(skb, FRA_SRC, sizeof(struct in6_addr),
229 &rule6->src.addr);
230
231 return 0;
232
233nla_put_failure:
234 return -ENOBUFS;
235}
236
237static u32 fib6_rule_default_pref(struct fib_rules_ops *ops)
238{
239 return 0x3FFF;
240}
241
242static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
243{
244 return nla_total_size(16)
245 + nla_total_size(16);
246}
247
248static struct fib_rules_ops fib6_rules_ops_template = {
249 .family = AF_INET6,
250 .rule_size = sizeof(struct fib6_rule),
251 .addr_size = sizeof(struct in6_addr),
252 .action = fib6_rule_action,
253 .match = fib6_rule_match,
254 .configure = fib6_rule_configure,
255 .compare = fib6_rule_compare,
256 .fill = fib6_rule_fill,
257 .default_pref = fib6_rule_default_pref,
258 .nlmsg_payload = fib6_rule_nlmsg_payload,
259 .nlgroup = RTNLGRP_IPV6_RULE,
260 .policy = fib6_rule_policy,
261 .owner = THIS_MODULE,
262 .fro_net = &init_net,
263};
264
265static int fib6_rules_net_init(struct net *net)
266{
267 int err = -ENOMEM;
268
269 net->ipv6.fib6_rules_ops = kmemdup(&fib6_rules_ops_template,
270 sizeof(*net->ipv6.fib6_rules_ops),
271 GFP_KERNEL);
272 if (!net->ipv6.fib6_rules_ops)
273 goto out;
274
275 net->ipv6.fib6_rules_ops->fro_net = net;
276 INIT_LIST_HEAD(&net->ipv6.fib6_rules_ops->rules_list);
277
278 err = fib_default_rule_add(net->ipv6.fib6_rules_ops, 0,
279 RT6_TABLE_LOCAL, FIB_RULE_PERMANENT);
280 if (err)
281 goto out_fib6_rules_ops;
282
283 err = fib_default_rule_add(net->ipv6.fib6_rules_ops,
284 0x7FFE, RT6_TABLE_MAIN, 0);
285 if (err)
286 goto out_fib6_default_rule_add;
287
288 err = fib_rules_register(net->ipv6.fib6_rules_ops);
289 if (err)
290 goto out_fib6_default_rule_add;
291out:
292 return err;
293
294out_fib6_default_rule_add:
295 fib_rules_cleanup_ops(net->ipv6.fib6_rules_ops);
296out_fib6_rules_ops:
297 kfree(net->ipv6.fib6_rules_ops);
298 goto out;
299}
300
301static void fib6_rules_net_exit(struct net *net)
302{
303 fib_rules_unregister(net->ipv6.fib6_rules_ops);
304 kfree(net->ipv6.fib6_rules_ops);
305}
306
307static struct pernet_operations fib6_rules_net_ops = {
308 .init = fib6_rules_net_init,
309 .exit = fib6_rules_net_exit,
310};
311
312int __init fib6_rules_init(void)
313{
314 return register_pernet_subsys(&fib6_rules_net_ops);
315}
316
317
318void fib6_rules_cleanup(void)
319{
320 unregister_pernet_subsys(&fib6_rules_net_ops);
321}
322
