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16#include <linux/netdevice.h>
17#include <linux/export.h>
18
19#include <net/fib_rules.h>
20#include <net/ipv6.h>
21#include <net/addrconf.h>
22#include <net/ip6_route.h>
23#include <net/netlink.h>
24
25struct fib6_rule {
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 flowi6 *fl6,
33 int flags, pol_lookup_t lookup)
34{
35 struct fib_lookup_arg arg = {
36 .lookup_ptr = lookup,
37 .flags = FIB_LOOKUP_NOREF,
38 };
39
40 fib_rules_lookup(net->ipv6.fib6_rules_ops,
41 flowi6_to_flowi(fl6), flags, &arg);
42
43 if (arg.result)
44 return arg.result;
45
46 dst_hold(&net->ipv6.ip6_null_entry->dst);
47 return &net->ipv6.ip6_null_entry->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 flowi6 *flp6 = &flp->u.ip6;
54 struct rt6_info *rt = NULL;
55 struct fib6_table *table;
56 struct net *net = rule->fr_net;
57 pol_lookup_t lookup = arg->lookup_ptr;
58 int err = 0;
59
60 switch (rule->action) {
61 case FR_ACT_TO_TBL:
62 break;
63 case FR_ACT_UNREACHABLE:
64 err = -ENETUNREACH;
65 rt = net->ipv6.ip6_null_entry;
66 goto discard_pkt;
67 default:
68 case FR_ACT_BLACKHOLE:
69 err = -EINVAL;
70 rt = net->ipv6.ip6_blk_hole_entry;
71 goto discard_pkt;
72 case FR_ACT_PROHIBIT:
73 err = -EACCES;
74 rt = net->ipv6.ip6_prohibit_entry;
75 goto discard_pkt;
76 }
77
78 table = fib6_get_table(net, rule->table);
79 if (!table) {
80 err = -EAGAIN;
81 goto out;
82 }
83
84 rt = lookup(net, table, flp6, flags);
85 if (rt != net->ipv6.ip6_null_entry) {
86 struct fib6_rule *r = (struct fib6_rule *)rule;
87
88
89
90
91
92 if ((rule->flags & FIB_RULE_FIND_SADDR) &&
93 r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
94 struct in6_addr saddr;
95
96 if (ipv6_dev_get_saddr(net,
97 ip6_dst_idev(&rt->dst)->dev,
98 &flp6->daddr,
99 rt6_flags2srcprefs(flags),
100 &saddr))
101 goto again;
102 if (!ipv6_prefix_equal(&saddr, &r->src.addr,
103 r->src.plen))
104 goto again;
105 flp6->saddr = saddr;
106 }
107 goto out;
108 }
109again:
110 ip6_rt_put(rt);
111 err = -EAGAIN;
112 rt = NULL;
113 goto out;
114
115discard_pkt:
116 dst_hold(&rt->dst);
117out:
118 arg->result = rt;
119 return err;
120}
121
122static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
123{
124 struct rt6_info *rt = (struct rt6_info *) arg->result;
125 struct net_device *dev = NULL;
126
127 if (rt->rt6i_idev)
128 dev = rt->rt6i_idev->dev;
129
130
131
132
133 if (rt->rt6i_dst.plen <= rule->suppress_prefixlen)
134 goto suppress_route;
135
136
137
138
139 if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
140 goto suppress_route;
141
142 return false;
143
144suppress_route:
145 ip6_rt_put(rt);
146 return true;
147}
148
149static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
150{
151 struct fib6_rule *r = (struct fib6_rule *) rule;
152 struct flowi6 *fl6 = &fl->u.ip6;
153
154 if (r->dst.plen &&
155 !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
156 return 0;
157
158
159
160
161
162
163 if (r->src.plen) {
164 if (flags & RT6_LOOKUP_F_HAS_SADDR) {
165 if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
166 r->src.plen))
167 return 0;
168 } else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
169 return 0;
170 }
171
172 if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel))
173 return 0;
174
175 return 1;
176}
177
178static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
179 FRA_GENERIC_POLICY,
180};
181
182static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
183 struct fib_rule_hdr *frh,
184 struct nlattr **tb)
185{
186 int err = -EINVAL;
187 struct net *net = sock_net(skb->sk);
188 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
189
190 if (rule->action == FR_ACT_TO_TBL) {
191 if (rule->table == RT6_TABLE_UNSPEC)
192 goto errout;
193
194 if (fib6_new_table(net, rule->table) == NULL) {
195 err = -ENOBUFS;
196 goto errout;
197 }
198 }
199
200 if (frh->src_len)
201 nla_memcpy(&rule6->src.addr, tb[FRA_SRC],
202 sizeof(struct in6_addr));
203
204 if (frh->dst_len)
205 nla_memcpy(&rule6->dst.addr, tb[FRA_DST],
206 sizeof(struct in6_addr));
207
208 rule6->src.plen = frh->src_len;
209 rule6->dst.plen = frh->dst_len;
210 rule6->tclass = frh->tos;
211
212 err = 0;
213errout:
214 return err;
215}
216
217static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
218 struct nlattr **tb)
219{
220 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
221
222 if (frh->src_len && (rule6->src.plen != frh->src_len))
223 return 0;
224
225 if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
226 return 0;
227
228 if (frh->tos && (rule6->tclass != frh->tos))
229 return 0;
230
231 if (frh->src_len &&
232 nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
233 return 0;
234
235 if (frh->dst_len &&
236 nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
237 return 0;
238
239 return 1;
240}
241
242static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
243 struct fib_rule_hdr *frh)
244{
245 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
246
247 frh->dst_len = rule6->dst.plen;
248 frh->src_len = rule6->src.plen;
249 frh->tos = rule6->tclass;
250
251 if ((rule6->dst.plen &&
252 nla_put(skb, FRA_DST, sizeof(struct in6_addr),
253 &rule6->dst.addr)) ||
254 (rule6->src.plen &&
255 nla_put(skb, FRA_SRC, sizeof(struct in6_addr),
256 &rule6->src.addr)))
257 goto nla_put_failure;
258 return 0;
259
260nla_put_failure:
261 return -ENOBUFS;
262}
263
264static u32 fib6_rule_default_pref(struct fib_rules_ops *ops)
265{
266 return 0x3FFF;
267}
268
269static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
270{
271 return nla_total_size(16)
272 + nla_total_size(16);
273}
274
275static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
276 .family = AF_INET6,
277 .rule_size = sizeof(struct fib6_rule),
278 .addr_size = sizeof(struct in6_addr),
279 .action = fib6_rule_action,
280 .match = fib6_rule_match,
281 .suppress = fib6_rule_suppress,
282 .configure = fib6_rule_configure,
283 .compare = fib6_rule_compare,
284 .fill = fib6_rule_fill,
285 .default_pref = fib6_rule_default_pref,
286 .nlmsg_payload = fib6_rule_nlmsg_payload,
287 .nlgroup = RTNLGRP_IPV6_RULE,
288 .policy = fib6_rule_policy,
289 .owner = THIS_MODULE,
290 .fro_net = &init_net,
291};
292
293static int __net_init fib6_rules_net_init(struct net *net)
294{
295 struct fib_rules_ops *ops;
296 int err = -ENOMEM;
297
298 ops = fib_rules_register(&fib6_rules_ops_template, net);
299 if (IS_ERR(ops))
300 return PTR_ERR(ops);
301 net->ipv6.fib6_rules_ops = ops;
302
303
304 err = fib_default_rule_add(net->ipv6.fib6_rules_ops, 0,
305 RT6_TABLE_LOCAL, 0);
306 if (err)
307 goto out_fib6_rules_ops;
308
309 err = fib_default_rule_add(net->ipv6.fib6_rules_ops,
310 0x7FFE, RT6_TABLE_MAIN, 0);
311 if (err)
312 goto out_fib6_rules_ops;
313
314out:
315 return err;
316
317out_fib6_rules_ops:
318 fib_rules_unregister(ops);
319 goto out;
320}
321
322static void __net_exit fib6_rules_net_exit(struct net *net)
323{
324 fib_rules_unregister(net->ipv6.fib6_rules_ops);
325}
326
327static struct pernet_operations fib6_rules_net_ops = {
328 .init = fib6_rules_net_init,
329 .exit = fib6_rules_net_exit,
330};
331
332int __init fib6_rules_init(void)
333{
334 return register_pernet_subsys(&fib6_rules_net_ops);
335}
336
337
338void fib6_rules_cleanup(void)
339{
340 unregister_pernet_subsys(&fib6_rules_net_ops);
341}
342
