Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * xfrm_input.c | |
3 | * | |
4 | * Changes: | |
5 | * YOSHIFUJI Hideaki @USAGI | |
6 | * Split up af-specific portion | |
a716c119 | 7 | * |
1da177e4 LT |
8 | */ |
9 | ||
10 | #include <linux/slab.h> | |
11 | #include <linux/module.h> | |
716062fd HX |
12 | #include <linux/netdevice.h> |
13 | #include <net/dst.h> | |
1da177e4 LT |
14 | #include <net/ip.h> |
15 | #include <net/xfrm.h> | |
049f8e2e AD |
16 | #include <net/ip_tunnels.h> |
17 | #include <net/ip6_tunnel.h> | |
1da177e4 | 18 | |
e18b890b | 19 | static struct kmem_cache *secpath_cachep __read_mostly; |
1da177e4 | 20 | |
2f32b51b SK |
21 | static DEFINE_SPINLOCK(xfrm_input_afinfo_lock); |
22 | static struct xfrm_input_afinfo __rcu *xfrm_input_afinfo[NPROTO]; | |
23 | ||
24 | int xfrm_input_register_afinfo(struct xfrm_input_afinfo *afinfo) | |
25 | { | |
26 | int err = 0; | |
27 | ||
28 | if (unlikely(afinfo == NULL)) | |
29 | return -EINVAL; | |
30 | if (unlikely(afinfo->family >= NPROTO)) | |
31 | return -EAFNOSUPPORT; | |
32 | spin_lock_bh(&xfrm_input_afinfo_lock); | |
33 | if (unlikely(xfrm_input_afinfo[afinfo->family] != NULL)) | |
f31e8d4f | 34 | err = -EEXIST; |
2f32b51b SK |
35 | else |
36 | rcu_assign_pointer(xfrm_input_afinfo[afinfo->family], afinfo); | |
37 | spin_unlock_bh(&xfrm_input_afinfo_lock); | |
38 | return err; | |
39 | } | |
40 | EXPORT_SYMBOL(xfrm_input_register_afinfo); | |
41 | ||
42 | int xfrm_input_unregister_afinfo(struct xfrm_input_afinfo *afinfo) | |
43 | { | |
44 | int err = 0; | |
45 | ||
46 | if (unlikely(afinfo == NULL)) | |
47 | return -EINVAL; | |
48 | if (unlikely(afinfo->family >= NPROTO)) | |
49 | return -EAFNOSUPPORT; | |
50 | spin_lock_bh(&xfrm_input_afinfo_lock); | |
51 | if (likely(xfrm_input_afinfo[afinfo->family] != NULL)) { | |
52 | if (unlikely(xfrm_input_afinfo[afinfo->family] != afinfo)) | |
53 | err = -EINVAL; | |
54 | else | |
55 | RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->family], NULL); | |
56 | } | |
57 | spin_unlock_bh(&xfrm_input_afinfo_lock); | |
58 | synchronize_rcu(); | |
59 | return err; | |
60 | } | |
61 | EXPORT_SYMBOL(xfrm_input_unregister_afinfo); | |
62 | ||
63 | static struct xfrm_input_afinfo *xfrm_input_get_afinfo(unsigned int family) | |
64 | { | |
65 | struct xfrm_input_afinfo *afinfo; | |
66 | ||
67 | if (unlikely(family >= NPROTO)) | |
68 | return NULL; | |
69 | rcu_read_lock(); | |
70 | afinfo = rcu_dereference(xfrm_input_afinfo[family]); | |
71 | if (unlikely(!afinfo)) | |
72 | rcu_read_unlock(); | |
73 | return afinfo; | |
74 | } | |
75 | ||
76 | static void xfrm_input_put_afinfo(struct xfrm_input_afinfo *afinfo) | |
77 | { | |
78 | rcu_read_unlock(); | |
79 | } | |
80 | ||
81 | static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol, | |
82 | int err) | |
83 | { | |
84 | int ret; | |
85 | struct xfrm_input_afinfo *afinfo = xfrm_input_get_afinfo(family); | |
86 | ||
87 | if (!afinfo) | |
88 | return -EAFNOSUPPORT; | |
89 | ||
90 | ret = afinfo->callback(skb, protocol, err); | |
91 | xfrm_input_put_afinfo(afinfo); | |
92 | ||
93 | return ret; | |
94 | } | |
95 | ||
1da177e4 LT |
96 | void __secpath_destroy(struct sec_path *sp) |
97 | { | |
98 | int i; | |
99 | for (i = 0; i < sp->len; i++) | |
dbe5b4aa | 100 | xfrm_state_put(sp->xvec[i]); |
1da177e4 LT |
101 | kmem_cache_free(secpath_cachep, sp); |
102 | } | |
103 | EXPORT_SYMBOL(__secpath_destroy); | |
104 | ||
105 | struct sec_path *secpath_dup(struct sec_path *src) | |
106 | { | |
107 | struct sec_path *sp; | |
108 | ||
54e6ecb2 | 109 | sp = kmem_cache_alloc(secpath_cachep, GFP_ATOMIC); |
1da177e4 LT |
110 | if (!sp) |
111 | return NULL; | |
112 | ||
113 | sp->len = 0; | |
114 | if (src) { | |
115 | int i; | |
116 | ||
117 | memcpy(sp, src, sizeof(*sp)); | |
118 | for (i = 0; i < sp->len; i++) | |
dbe5b4aa | 119 | xfrm_state_hold(sp->xvec[i]); |
1da177e4 LT |
120 | } |
121 | atomic_set(&sp->refcnt, 1); | |
122 | return sp; | |
123 | } | |
124 | EXPORT_SYMBOL(secpath_dup); | |
125 | ||
126 | /* Fetch spi and seq from ipsec header */ | |
127 | ||
6067b2ba | 128 | int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq) |
1da177e4 LT |
129 | { |
130 | int offset, offset_seq; | |
44072500 | 131 | int hlen; |
1da177e4 LT |
132 | |
133 | switch (nexthdr) { | |
134 | case IPPROTO_AH: | |
44072500 | 135 | hlen = sizeof(struct ip_auth_hdr); |
1da177e4 LT |
136 | offset = offsetof(struct ip_auth_hdr, spi); |
137 | offset_seq = offsetof(struct ip_auth_hdr, seq_no); | |
138 | break; | |
139 | case IPPROTO_ESP: | |
44072500 | 140 | hlen = sizeof(struct ip_esp_hdr); |
1da177e4 LT |
141 | offset = offsetof(struct ip_esp_hdr, spi); |
142 | offset_seq = offsetof(struct ip_esp_hdr, seq_no); | |
143 | break; | |
144 | case IPPROTO_COMP: | |
145 | if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr))) | |
146 | return -EINVAL; | |
3e94c2dc | 147 | *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2))); |
1da177e4 LT |
148 | *seq = 0; |
149 | return 0; | |
150 | default: | |
151 | return 1; | |
152 | } | |
153 | ||
44072500 | 154 | if (!pskb_may_pull(skb, hlen)) |
1da177e4 LT |
155 | return -EINVAL; |
156 | ||
3e94c2dc WC |
157 | *spi = *(__be32 *)(skb_transport_header(skb) + offset); |
158 | *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq); | |
1da177e4 LT |
159 | return 0; |
160 | } | |
1da177e4 | 161 | |
227620e2 HX |
162 | int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb) |
163 | { | |
df9dcb45 | 164 | struct xfrm_mode *inner_mode = x->inner_mode; |
227620e2 HX |
165 | int err; |
166 | ||
167 | err = x->outer_mode->afinfo->extract_input(x, skb); | |
168 | if (err) | |
169 | return err; | |
170 | ||
df9dcb45 KM |
171 | if (x->sel.family == AF_UNSPEC) { |
172 | inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); | |
173 | if (inner_mode == NULL) | |
174 | return -EAFNOSUPPORT; | |
175 | } | |
176 | ||
177 | skb->protocol = inner_mode->afinfo->eth_proto; | |
178 | return inner_mode->input2(x, skb); | |
227620e2 HX |
179 | } |
180 | EXPORT_SYMBOL(xfrm_prepare_input); | |
181 | ||
716062fd HX |
182 | int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) |
183 | { | |
bd235e3c | 184 | struct net *net = dev_net(skb->dev); |
716062fd HX |
185 | int err; |
186 | __be32 seq; | |
2cd08467 | 187 | __be32 seq_hi; |
3328715e | 188 | struct xfrm_state *x = NULL; |
1bf06cd2 | 189 | xfrm_address_t *daddr; |
df9dcb45 | 190 | struct xfrm_mode *inner_mode; |
049f8e2e | 191 | u32 mark = skb->mark; |
2fcb45b6 | 192 | unsigned int family; |
716062fd | 193 | int decaps = 0; |
1bf06cd2 HX |
194 | int async = 0; |
195 | ||
196 | /* A negative encap_type indicates async resumption. */ | |
197 | if (encap_type < 0) { | |
198 | async = 1; | |
00501121 | 199 | x = xfrm_input_state(skb); |
1ce3644a | 200 | seq = XFRM_SKB_CB(skb)->seq.input.low; |
3328715e | 201 | family = x->outer_mode->afinfo->family; |
1bf06cd2 HX |
202 | goto resume; |
203 | } | |
716062fd | 204 | |
3328715e SK |
205 | daddr = (xfrm_address_t *)(skb_network_header(skb) + |
206 | XFRM_SPI_SKB_CB(skb)->daddroff); | |
207 | family = XFRM_SPI_SKB_CB(skb)->family; | |
208 | ||
049f8e2e AD |
209 | /* if tunnel is present override skb->mark value with tunnel i_key */ |
210 | if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4) { | |
211 | switch (family) { | |
212 | case AF_INET: | |
213 | mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key); | |
214 | break; | |
215 | case AF_INET6: | |
216 | mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key); | |
217 | break; | |
218 | } | |
219 | } | |
220 | ||
b2aa5e9d HX |
221 | /* Allocate new secpath or COW existing one. */ |
222 | if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) { | |
223 | struct sec_path *sp; | |
224 | ||
225 | sp = secpath_dup(skb->sp); | |
0aa64774 | 226 | if (!sp) { |
59c9940e | 227 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR); |
b2aa5e9d | 228 | goto drop; |
0aa64774 | 229 | } |
b2aa5e9d HX |
230 | if (skb->sp) |
231 | secpath_put(skb->sp); | |
232 | skb->sp = sp; | |
233 | } | |
234 | ||
716062fd | 235 | seq = 0; |
0aa64774 | 236 | if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) { |
59c9940e | 237 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); |
716062fd | 238 | goto drop; |
0aa64774 | 239 | } |
716062fd HX |
240 | |
241 | do { | |
0aa64774 | 242 | if (skb->sp->len == XFRM_MAX_DEPTH) { |
59c9940e | 243 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); |
716062fd | 244 | goto drop; |
0aa64774 | 245 | } |
716062fd | 246 | |
049f8e2e | 247 | x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family); |
0aa64774 | 248 | if (x == NULL) { |
59c9940e | 249 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); |
afeb14b4 | 250 | xfrm_audit_state_notfound(skb, family, spi, seq); |
716062fd | 251 | goto drop; |
0aa64774 | 252 | } |
716062fd | 253 | |
b2aa5e9d HX |
254 | skb->sp->xvec[skb->sp->len++] = x; |
255 | ||
716062fd | 256 | spin_lock(&x->lock); |
4c4d41f2 | 257 | |
0aa64774 | 258 | if (unlikely(x->km.state != XFRM_STATE_VALID)) { |
dc0565ce LR |
259 | if (x->km.state == XFRM_STATE_ACQ) |
260 | XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR); | |
261 | else | |
262 | XFRM_INC_STATS(net, | |
263 | LINUX_MIB_XFRMINSTATEINVALID); | |
716062fd | 264 | goto drop_unlock; |
0aa64774 | 265 | } |
716062fd | 266 | |
3de77cf2 DM |
267 | if ((x->encap ? x->encap->encap_type : 0) != encap_type) { |
268 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); | |
269 | goto drop_unlock; | |
270 | } | |
271 | ||
36ae0148 | 272 | if (x->repl->check(x, skb, seq)) { |
59c9940e | 273 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR); |
716062fd | 274 | goto drop_unlock; |
0aa64774 | 275 | } |
716062fd | 276 | |
0aa64774 | 277 | if (xfrm_state_check_expire(x)) { |
59c9940e | 278 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED); |
716062fd | 279 | goto drop_unlock; |
0aa64774 | 280 | } |
716062fd | 281 | |
0ebea8ef HX |
282 | spin_unlock(&x->lock); |
283 | ||
68c11e98 AD |
284 | if (xfrm_tunnel_check(skb, x, family)) { |
285 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR); | |
286 | goto drop; | |
287 | } | |
288 | ||
2cd08467 SK |
289 | seq_hi = htonl(xfrm_replay_seqhi(x, seq)); |
290 | ||
1ce3644a | 291 | XFRM_SKB_CB(skb)->seq.input.low = seq; |
2cd08467 | 292 | XFRM_SKB_CB(skb)->seq.input.hi = seq_hi; |
1bf06cd2 | 293 | |
3bc07321 SK |
294 | skb_dst_force(skb); |
295 | ||
716062fd | 296 | nexthdr = x->type->input(x, skb); |
0ebea8ef | 297 | |
1bf06cd2 HX |
298 | if (nexthdr == -EINPROGRESS) |
299 | return 0; | |
1bf06cd2 | 300 | resume: |
0ebea8ef | 301 | spin_lock(&x->lock); |
668dc8af | 302 | if (nexthdr <= 0) { |
9dd3245a HX |
303 | if (nexthdr == -EBADMSG) { |
304 | xfrm_audit_state_icvfail(x, skb, | |
305 | x->type->proto); | |
668dc8af | 306 | x->stats.integrity_failed++; |
9dd3245a | 307 | } |
59c9940e | 308 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR); |
716062fd | 309 | goto drop_unlock; |
668dc8af | 310 | } |
716062fd | 311 | |
716062fd HX |
312 | /* only the first xfrm gets the encap type */ |
313 | encap_type = 0; | |
314 | ||
3b59df46 | 315 | if (async && x->repl->recheck(x, skb, seq)) { |
bcf66bf5 SK |
316 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR); |
317 | goto drop_unlock; | |
318 | } | |
319 | ||
9fdc4883 | 320 | x->repl->advance(x, seq); |
716062fd HX |
321 | |
322 | x->curlft.bytes += skb->len; | |
323 | x->curlft.packets++; | |
324 | ||
325 | spin_unlock(&x->lock); | |
326 | ||
60d5fcfb HX |
327 | XFRM_MODE_SKB_CB(skb)->protocol = nexthdr; |
328 | ||
df9dcb45 KM |
329 | inner_mode = x->inner_mode; |
330 | ||
331 | if (x->sel.family == AF_UNSPEC) { | |
332 | inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); | |
333 | if (inner_mode == NULL) | |
334 | goto drop; | |
335 | } | |
336 | ||
337 | if (inner_mode->input(x, skb)) { | |
59c9940e | 338 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR); |
716062fd | 339 | goto drop; |
0aa64774 | 340 | } |
716062fd HX |
341 | |
342 | if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) { | |
343 | decaps = 1; | |
344 | break; | |
345 | } | |
346 | ||
1bf06cd2 HX |
347 | /* |
348 | * We need the inner address. However, we only get here for | |
349 | * transport mode so the outer address is identical. | |
350 | */ | |
351 | daddr = &x->id.daddr; | |
2fcb45b6 | 352 | family = x->outer_mode->afinfo->family; |
1bf06cd2 | 353 | |
716062fd | 354 | err = xfrm_parse_spi(skb, nexthdr, &spi, &seq); |
0aa64774 | 355 | if (err < 0) { |
59c9940e | 356 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); |
716062fd | 357 | goto drop; |
0aa64774 | 358 | } |
716062fd HX |
359 | } while (!err); |
360 | ||
3328715e SK |
361 | err = xfrm_rcv_cb(skb, family, x->type->proto, 0); |
362 | if (err) | |
363 | goto drop; | |
364 | ||
716062fd HX |
365 | nf_reset(skb); |
366 | ||
367 | if (decaps) { | |
adf30907 | 368 | skb_dst_drop(skb); |
716062fd HX |
369 | netif_rx(skb); |
370 | return 0; | |
371 | } else { | |
1bf06cd2 | 372 | return x->inner_mode->afinfo->transport_finish(skb, async); |
716062fd HX |
373 | } |
374 | ||
375 | drop_unlock: | |
376 | spin_unlock(&x->lock); | |
716062fd | 377 | drop: |
3328715e | 378 | xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1); |
716062fd HX |
379 | kfree_skb(skb); |
380 | return 0; | |
381 | } | |
382 | EXPORT_SYMBOL(xfrm_input); | |
383 | ||
1bf06cd2 HX |
384 | int xfrm_input_resume(struct sk_buff *skb, int nexthdr) |
385 | { | |
386 | return xfrm_input(skb, nexthdr, 0, -1); | |
387 | } | |
388 | EXPORT_SYMBOL(xfrm_input_resume); | |
389 | ||
1da177e4 LT |
390 | void __init xfrm_input_init(void) |
391 | { | |
392 | secpath_cachep = kmem_cache_create("secpath_cache", | |
393 | sizeof(struct sec_path), | |
e5d679f3 | 394 | 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, |
20c2df83 | 395 | NULL); |
1da177e4 | 396 | } |