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Commit | Line | Data |
---|---|---|
e905a9ed | 1 | /* |
1da177e4 LT |
2 | * xfrm4_policy.c |
3 | * | |
4 | * Changes: | |
5 | * Kazunori MIYAZAWA @USAGI | |
6 | * YOSHIFUJI Hideaki @USAGI | |
7 | * Split up af-specific portion | |
e905a9ed | 8 | * |
1da177e4 LT |
9 | */ |
10 | ||
66cdb3ca HX |
11 | #include <linux/err.h> |
12 | #include <linux/kernel.h> | |
aabc9761 | 13 | #include <linux/inetdevice.h> |
cc9ff19d | 14 | #include <linux/if_tunnel.h> |
45ff5a3f | 15 | #include <net/dst.h> |
1da177e4 LT |
16 | #include <net/xfrm.h> |
17 | #include <net/ip.h> | |
385add90 | 18 | #include <net/l3mdev.h> |
1da177e4 | 19 | |
8f01cb08 | 20 | static struct dst_entry *__xfrm4_dst_lookup(struct net *net, struct flowi4 *fl4, |
42a7b32b | 21 | int tos, int oif, |
8f01cb08 DM |
22 | const xfrm_address_t *saddr, |
23 | const xfrm_address_t *daddr) | |
1da177e4 | 24 | { |
66cdb3ca | 25 | struct rtable *rt; |
a1e59abf | 26 | |
8f01cb08 DM |
27 | memset(fl4, 0, sizeof(*fl4)); |
28 | fl4->daddr = daddr->a4; | |
29 | fl4->flowi4_tos = tos; | |
11d7a0bb | 30 | fl4->flowi4_oif = l3mdev_master_ifindex_by_index(net, oif); |
66cdb3ca | 31 | if (saddr) |
8f01cb08 | 32 | fl4->saddr = saddr->a4; |
66cdb3ca | 33 | |
58189ca7 DA |
34 | fl4->flowi4_flags = FLOWI_FLAG_SKIP_NH_OIF; |
35 | ||
8f01cb08 | 36 | rt = __ip_route_output_key(net, fl4); |
b23dd4fe DM |
37 | if (!IS_ERR(rt)) |
38 | return &rt->dst; | |
39 | ||
40 | return ERR_CAST(rt); | |
66cdb3ca HX |
41 | } |
42 | ||
42a7b32b | 43 | static struct dst_entry *xfrm4_dst_lookup(struct net *net, int tos, int oif, |
8f01cb08 DM |
44 | const xfrm_address_t *saddr, |
45 | const xfrm_address_t *daddr) | |
46 | { | |
47 | struct flowi4 fl4; | |
48 | ||
42a7b32b | 49 | return __xfrm4_dst_lookup(net, &fl4, tos, oif, saddr, daddr); |
8f01cb08 DM |
50 | } |
51 | ||
42a7b32b | 52 | static int xfrm4_get_saddr(struct net *net, int oif, |
fbda33b2 | 53 | xfrm_address_t *saddr, xfrm_address_t *daddr) |
66cdb3ca HX |
54 | { |
55 | struct dst_entry *dst; | |
8f01cb08 | 56 | struct flowi4 fl4; |
66cdb3ca | 57 | |
42a7b32b | 58 | dst = __xfrm4_dst_lookup(net, &fl4, 0, oif, NULL, daddr); |
66cdb3ca HX |
59 | if (IS_ERR(dst)) |
60 | return -EHOSTUNREACH; | |
61 | ||
8f01cb08 | 62 | saddr->a4 = fl4.saddr; |
66cdb3ca HX |
63 | dst_release(dst); |
64 | return 0; | |
a1e59abf PM |
65 | } |
66 | ||
05d84025 | 67 | static int xfrm4_get_tos(const struct flowi *fl) |
1da177e4 | 68 | { |
7e1dc7b6 | 69 | return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; /* Strip ECN bits */ |
25ee3286 | 70 | } |
1da177e4 | 71 | |
a1b05140 MN |
72 | static int xfrm4_init_path(struct xfrm_dst *path, struct dst_entry *dst, |
73 | int nfheader_len) | |
74 | { | |
75 | return 0; | |
76 | } | |
77 | ||
87c1e12b | 78 | static int xfrm4_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, |
0c7b3eef | 79 | const struct flowi *fl) |
25ee3286 HX |
80 | { |
81 | struct rtable *rt = (struct rtable *)xdst->route; | |
7e1dc7b6 | 82 | const struct flowi4 *fl4 = &fl->u.ip4; |
1da177e4 | 83 | |
b7323396 | 84 | xdst->u.rt.rt_iif = fl4->flowi4_iif; |
1da177e4 | 85 | |
25ee3286 HX |
86 | xdst->u.dst.dev = dev; |
87 | dev_hold(dev); | |
43372262 | 88 | |
25ee3286 HX |
89 | /* Sheit... I remember I did this right. Apparently, |
90 | * it was magically lost, so this code needs audit */ | |
9917e1e8 | 91 | xdst->u.rt.rt_is_input = rt->rt_is_input; |
25ee3286 HX |
92 | xdst->u.rt.rt_flags = rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | |
93 | RTCF_LOCAL); | |
94 | xdst->u.rt.rt_type = rt->rt_type; | |
25ee3286 | 95 | xdst->u.rt.rt_gateway = rt->rt_gateway; |
155e8336 | 96 | xdst->u.rt.rt_uses_gateway = rt->rt_uses_gateway; |
5943634f | 97 | xdst->u.rt.rt_pmtu = rt->rt_pmtu; |
b7503e0c | 98 | xdst->u.rt.rt_table_id = rt->rt_table_id; |
caacf05e | 99 | INIT_LIST_HEAD(&xdst->u.rt.rt_uncached); |
0fc845c7 | 100 | rt_add_uncached_list(&xdst->u.rt); |
1da177e4 | 101 | |
1da177e4 | 102 | return 0; |
1da177e4 LT |
103 | } |
104 | ||
105 | static void | |
d5422efe | 106 | _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse) |
1da177e4 | 107 | { |
b71d1d42 | 108 | const struct iphdr *iph = ip_hdr(skb); |
d56f90a7 | 109 | u8 *xprth = skb_network_header(skb) + iph->ihl * 4; |
7e1dc7b6 | 110 | struct flowi4 *fl4 = &fl->u.ip4; |
84502b5e SK |
111 | int oif = 0; |
112 | ||
385add90 | 113 | if (skb_dst(skb)) |
e0d56fdd | 114 | oif = skb_dst(skb)->dev->ifindex; |
1da177e4 | 115 | |
7e1dc7b6 DM |
116 | memset(fl4, 0, sizeof(struct flowi4)); |
117 | fl4->flowi4_mark = skb->mark; | |
84502b5e | 118 | fl4->flowi4_oif = reverse ? skb->skb_iif : oif; |
44b451f1 | 119 | |
56f8a75c | 120 | if (!ip_is_fragment(iph)) { |
1da177e4 LT |
121 | switch (iph->protocol) { |
122 | case IPPROTO_UDP: | |
ba4e58ec | 123 | case IPPROTO_UDPLITE: |
1da177e4 LT |
124 | case IPPROTO_TCP: |
125 | case IPPROTO_SCTP: | |
9e999993 | 126 | case IPPROTO_DCCP: |
c615c9f3 WY |
127 | if (xprth + 4 < skb->data || |
128 | pskb_may_pull(skb, xprth + 4 - skb->data)) { | |
ea673a4d SK |
129 | __be16 *ports; |
130 | ||
131 | xprth = skb_network_header(skb) + iph->ihl * 4; | |
132 | ports = (__be16 *)xprth; | |
1da177e4 | 133 | |
9cce96df DM |
134 | fl4->fl4_sport = ports[!!reverse]; |
135 | fl4->fl4_dport = ports[!reverse]; | |
1da177e4 LT |
136 | } |
137 | break; | |
138 | ||
139 | case IPPROTO_ICMP: | |
1a14f1e5 SK |
140 | if (xprth + 2 < skb->data || |
141 | pskb_may_pull(skb, xprth + 2 - skb->data)) { | |
ea673a4d SK |
142 | u8 *icmp; |
143 | ||
144 | xprth = skb_network_header(skb) + iph->ihl * 4; | |
145 | icmp = xprth; | |
1da177e4 | 146 | |
9cce96df DM |
147 | fl4->fl4_icmp_type = icmp[0]; |
148 | fl4->fl4_icmp_code = icmp[1]; | |
1da177e4 LT |
149 | } |
150 | break; | |
151 | ||
152 | case IPPROTO_ESP: | |
1a14f1e5 SK |
153 | if (xprth + 4 < skb->data || |
154 | pskb_may_pull(skb, xprth + 4 - skb->data)) { | |
ea673a4d SK |
155 | __be32 *ehdr; |
156 | ||
157 | xprth = skb_network_header(skb) + iph->ihl * 4; | |
158 | ehdr = (__be32 *)xprth; | |
1da177e4 | 159 | |
9cce96df | 160 | fl4->fl4_ipsec_spi = ehdr[0]; |
1da177e4 LT |
161 | } |
162 | break; | |
163 | ||
164 | case IPPROTO_AH: | |
1a14f1e5 SK |
165 | if (xprth + 8 < skb->data || |
166 | pskb_may_pull(skb, xprth + 8 - skb->data)) { | |
ea673a4d SK |
167 | __be32 *ah_hdr; |
168 | ||
169 | xprth = skb_network_header(skb) + iph->ihl * 4; | |
170 | ah_hdr = (__be32 *)xprth; | |
1da177e4 | 171 | |
9cce96df | 172 | fl4->fl4_ipsec_spi = ah_hdr[1]; |
1da177e4 LT |
173 | } |
174 | break; | |
175 | ||
176 | case IPPROTO_COMP: | |
1a14f1e5 SK |
177 | if (xprth + 4 < skb->data || |
178 | pskb_may_pull(skb, xprth + 4 - skb->data)) { | |
ea673a4d SK |
179 | __be16 *ipcomp_hdr; |
180 | ||
181 | xprth = skb_network_header(skb) + iph->ihl * 4; | |
182 | ipcomp_hdr = (__be16 *)xprth; | |
1da177e4 | 183 | |
9cce96df | 184 | fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1])); |
1da177e4 LT |
185 | } |
186 | break; | |
cc9ff19d TT |
187 | |
188 | case IPPROTO_GRE: | |
1a14f1e5 SK |
189 | if (xprth + 12 < skb->data || |
190 | pskb_may_pull(skb, xprth + 12 - skb->data)) { | |
ea673a4d SK |
191 | __be16 *greflags; |
192 | __be32 *gre_hdr; | |
193 | ||
194 | xprth = skb_network_header(skb) + iph->ihl * 4; | |
195 | greflags = (__be16 *)xprth; | |
196 | gre_hdr = (__be32 *)xprth; | |
cc9ff19d TT |
197 | |
198 | if (greflags[0] & GRE_KEY) { | |
199 | if (greflags[0] & GRE_CSUM) | |
200 | gre_hdr++; | |
9cce96df | 201 | fl4->fl4_gre_key = gre_hdr[1]; |
cc9ff19d TT |
202 | } |
203 | } | |
204 | break; | |
205 | ||
1da177e4 | 206 | default: |
9cce96df | 207 | fl4->fl4_ipsec_spi = 0; |
1da177e4 | 208 | break; |
3ff50b79 | 209 | } |
1da177e4 | 210 | } |
7e1dc7b6 DM |
211 | fl4->flowi4_proto = iph->protocol; |
212 | fl4->daddr = reverse ? iph->saddr : iph->daddr; | |
213 | fl4->saddr = reverse ? iph->daddr : iph->saddr; | |
214 | fl4->flowi4_tos = iph->tos; | |
1da177e4 LT |
215 | } |
216 | ||
569d3645 | 217 | static inline int xfrm4_garbage_collect(struct dst_ops *ops) |
1da177e4 | 218 | { |
d7c7544c AD |
219 | struct net *net = container_of(ops, struct net, xfrm.xfrm4_dst_ops); |
220 | ||
3d7d25a6 | 221 | xfrm_garbage_collect_deferred(net); |
fc66f95c | 222 | return (dst_entries_get_slow(ops) > ops->gc_thresh * 2); |
1da177e4 LT |
223 | } |
224 | ||
6700c270 DM |
225 | static void xfrm4_update_pmtu(struct dst_entry *dst, struct sock *sk, |
226 | struct sk_buff *skb, u32 mtu) | |
1da177e4 LT |
227 | { |
228 | struct xfrm_dst *xdst = (struct xfrm_dst *)dst; | |
229 | struct dst_entry *path = xdst->route; | |
230 | ||
6700c270 | 231 | path->ops->update_pmtu(path, sk, skb, mtu); |
1da177e4 LT |
232 | } |
233 | ||
6700c270 DM |
234 | static void xfrm4_redirect(struct dst_entry *dst, struct sock *sk, |
235 | struct sk_buff *skb) | |
55be7a9c DM |
236 | { |
237 | struct xfrm_dst *xdst = (struct xfrm_dst *)dst; | |
238 | struct dst_entry *path = xdst->route; | |
239 | ||
6700c270 | 240 | path->ops->redirect(path, sk, skb); |
55be7a9c DM |
241 | } |
242 | ||
aabc9761 HX |
243 | static void xfrm4_dst_destroy(struct dst_entry *dst) |
244 | { | |
245 | struct xfrm_dst *xdst = (struct xfrm_dst *)dst; | |
246 | ||
62fa8a84 | 247 | dst_destroy_metrics_generic(dst); |
0fc845c7 XL |
248 | if (xdst->u.rt.rt_uncached_list) |
249 | rt_del_uncached_list(&xdst->u.rt); | |
aabc9761 HX |
250 | xfrm_dst_destroy(xdst); |
251 | } | |
252 | ||
253 | static void xfrm4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, | |
254 | int unregister) | |
255 | { | |
aabc9761 HX |
256 | if (!unregister) |
257 | return; | |
258 | ||
aabc9761 HX |
259 | xfrm_dst_ifdown(dst, dev); |
260 | } | |
261 | ||
a8a572a6 | 262 | static struct dst_ops xfrm4_dst_ops_template = { |
1da177e4 | 263 | .family = AF_INET, |
1da177e4 LT |
264 | .gc = xfrm4_garbage_collect, |
265 | .update_pmtu = xfrm4_update_pmtu, | |
55be7a9c | 266 | .redirect = xfrm4_redirect, |
62fa8a84 | 267 | .cow_metrics = dst_cow_metrics_generic, |
aabc9761 HX |
268 | .destroy = xfrm4_dst_destroy, |
269 | .ifdown = xfrm4_dst_ifdown, | |
862b82c6 | 270 | .local_out = __ip_local_out, |
c386578f | 271 | .gc_thresh = INT_MAX, |
1da177e4 LT |
272 | }; |
273 | ||
37b10383 | 274 | static const struct xfrm_policy_afinfo xfrm4_policy_afinfo = { |
a8a572a6 | 275 | .dst_ops = &xfrm4_dst_ops_template, |
1da177e4 | 276 | .dst_lookup = xfrm4_dst_lookup, |
a1e59abf | 277 | .get_saddr = xfrm4_get_saddr, |
1da177e4 | 278 | .decode_session = _decode_session4, |
25ee3286 | 279 | .get_tos = xfrm4_get_tos, |
a1b05140 | 280 | .init_path = xfrm4_init_path, |
25ee3286 | 281 | .fill_dst = xfrm4_fill_dst, |
2774c131 | 282 | .blackhole_route = ipv4_blackhole_route, |
1da177e4 LT |
283 | }; |
284 | ||
f816700a | 285 | #ifdef CONFIG_SYSCTL |
a44a4a00 NH |
286 | static struct ctl_table xfrm4_policy_table[] = { |
287 | { | |
a44a4a00 | 288 | .procname = "xfrm4_gc_thresh", |
d7c7544c | 289 | .data = &init_net.xfrm.xfrm4_dst_ops.gc_thresh, |
a44a4a00 NH |
290 | .maxlen = sizeof(int), |
291 | .mode = 0644, | |
292 | .proc_handler = proc_dointvec, | |
293 | }, | |
294 | { } | |
295 | }; | |
296 | ||
318d3cc0 | 297 | static __net_init int xfrm4_net_sysctl_init(struct net *net) |
8d068875 MK |
298 | { |
299 | struct ctl_table *table; | |
300 | struct ctl_table_header *hdr; | |
301 | ||
302 | table = xfrm4_policy_table; | |
303 | if (!net_eq(net, &init_net)) { | |
304 | table = kmemdup(table, sizeof(xfrm4_policy_table), GFP_KERNEL); | |
305 | if (!table) | |
306 | goto err_alloc; | |
307 | ||
308 | table[0].data = &net->xfrm.xfrm4_dst_ops.gc_thresh; | |
309 | } | |
310 | ||
311 | hdr = register_net_sysctl(net, "net/ipv4", table); | |
312 | if (!hdr) | |
313 | goto err_reg; | |
314 | ||
315 | net->ipv4.xfrm4_hdr = hdr; | |
316 | return 0; | |
317 | ||
318 | err_reg: | |
319 | if (!net_eq(net, &init_net)) | |
320 | kfree(table); | |
321 | err_alloc: | |
322 | return -ENOMEM; | |
323 | } | |
324 | ||
318d3cc0 | 325 | static __net_exit void xfrm4_net_sysctl_exit(struct net *net) |
8d068875 MK |
326 | { |
327 | struct ctl_table *table; | |
328 | ||
51456b29 | 329 | if (!net->ipv4.xfrm4_hdr) |
8d068875 MK |
330 | return; |
331 | ||
332 | table = net->ipv4.xfrm4_hdr->ctl_table_arg; | |
333 | unregister_net_sysctl_table(net->ipv4.xfrm4_hdr); | |
334 | if (!net_eq(net, &init_net)) | |
335 | kfree(table); | |
336 | } | |
a8a572a6 | 337 | #else /* CONFIG_SYSCTL */ |
318d3cc0 | 338 | static inline int xfrm4_net_sysctl_init(struct net *net) |
a8a572a6 DS |
339 | { |
340 | return 0; | |
341 | } | |
342 | ||
318d3cc0 | 343 | static inline void xfrm4_net_sysctl_exit(struct net *net) |
a8a572a6 DS |
344 | { |
345 | } | |
346 | #endif | |
347 | ||
348 | static int __net_init xfrm4_net_init(struct net *net) | |
349 | { | |
350 | int ret; | |
351 | ||
352 | memcpy(&net->xfrm.xfrm4_dst_ops, &xfrm4_dst_ops_template, | |
353 | sizeof(xfrm4_dst_ops_template)); | |
354 | ret = dst_entries_init(&net->xfrm.xfrm4_dst_ops); | |
355 | if (ret) | |
356 | return ret; | |
357 | ||
358 | ret = xfrm4_net_sysctl_init(net); | |
359 | if (ret) | |
360 | dst_entries_destroy(&net->xfrm.xfrm4_dst_ops); | |
361 | ||
362 | return ret; | |
363 | } | |
364 | ||
365 | static void __net_exit xfrm4_net_exit(struct net *net) | |
366 | { | |
367 | xfrm4_net_sysctl_exit(net); | |
368 | dst_entries_destroy(&net->xfrm.xfrm4_dst_ops); | |
369 | } | |
8d068875 MK |
370 | |
371 | static struct pernet_operations __net_initdata xfrm4_net_ops = { | |
372 | .init = xfrm4_net_init, | |
373 | .exit = xfrm4_net_exit, | |
374 | }; | |
a44a4a00 | 375 | |
1da177e4 LT |
376 | static void __init xfrm4_policy_init(void) |
377 | { | |
a2817d8b | 378 | xfrm_policy_register_afinfo(&xfrm4_policy_afinfo, AF_INET); |
1da177e4 LT |
379 | } |
380 | ||
703fb94e | 381 | void __init xfrm4_init(void) |
1da177e4 | 382 | { |
d7c7544c AD |
383 | xfrm4_state_init(); |
384 | xfrm4_policy_init(); | |
2f32b51b | 385 | xfrm4_protocol_init(); |
8d068875 | 386 | register_pernet_subsys(&xfrm4_net_ops); |
1da177e4 LT |
387 | } |
388 |