blob: b4a13178fb40176e41d90ff171e971ac7d6f8935 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * xfrm_input.c
3 *
4 * Changes:
5 * YOSHIFUJI Hideaki @USAGI
6 * Split up af-specific portion
YOSHIFUJI Hideakia716c112007-02-09 23:25:29 +09007 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 */
9
10#include <linux/slab.h>
11#include <linux/module.h>
Herbert Xu716062f2007-11-13 21:44:23 -080012#include <linux/netdevice.h>
13#include <net/dst.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <net/ip.h>
15#include <net/xfrm.h>
16
Christoph Lametere18b8902006-12-06 20:33:20 -080017static struct kmem_cache *secpath_cachep __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -070018
19void __secpath_destroy(struct sec_path *sp)
20{
21 int i;
22 for (i = 0; i < sp->len; i++)
Herbert Xudbe5b4a2006-04-01 00:54:16 -080023 xfrm_state_put(sp->xvec[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -070024 kmem_cache_free(secpath_cachep, sp);
25}
26EXPORT_SYMBOL(__secpath_destroy);
27
28struct sec_path *secpath_dup(struct sec_path *src)
29{
30 struct sec_path *sp;
31
Christoph Lameter54e6ecb2006-12-06 20:33:16 -080032 sp = kmem_cache_alloc(secpath_cachep, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -070033 if (!sp)
34 return NULL;
35
36 sp->len = 0;
37 if (src) {
38 int i;
39
40 memcpy(sp, src, sizeof(*sp));
41 for (i = 0; i < sp->len; i++)
Herbert Xudbe5b4a2006-04-01 00:54:16 -080042 xfrm_state_hold(sp->xvec[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 }
44 atomic_set(&sp->refcnt, 1);
45 return sp;
46}
47EXPORT_SYMBOL(secpath_dup);
48
49/* Fetch spi and seq from ipsec header */
50
Al Viro6067b2b2006-09-27 18:47:59 -070051int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
Linus Torvalds1da177e2005-04-16 15:20:36 -070052{
53 int offset, offset_seq;
Herbert Xu44072502007-10-17 21:30:34 -070054 int hlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -070055
56 switch (nexthdr) {
57 case IPPROTO_AH:
Herbert Xu44072502007-10-17 21:30:34 -070058 hlen = sizeof(struct ip_auth_hdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 offset = offsetof(struct ip_auth_hdr, spi);
60 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
61 break;
62 case IPPROTO_ESP:
Herbert Xu44072502007-10-17 21:30:34 -070063 hlen = sizeof(struct ip_esp_hdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 offset = offsetof(struct ip_esp_hdr, spi);
65 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
66 break;
67 case IPPROTO_COMP:
68 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
69 return -EINVAL;
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -070070 *spi = htonl(ntohs(*(__be16*)(skb_transport_header(skb) + 2)));
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 *seq = 0;
72 return 0;
73 default:
74 return 1;
75 }
76
Herbert Xu44072502007-10-17 21:30:34 -070077 if (!pskb_may_pull(skb, hlen))
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 return -EINVAL;
79
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -070080 *spi = *(__be32*)(skb_transport_header(skb) + offset);
81 *seq = *(__be32*)(skb_transport_header(skb) + offset_seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 return 0;
83}
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
Herbert Xu227620e2007-11-13 21:41:28 -080085int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
86{
Kazunori MIYAZAWAdf9dcb42008-03-24 14:51:51 -070087 struct xfrm_mode *inner_mode = x->inner_mode;
Herbert Xu227620e2007-11-13 21:41:28 -080088 int err;
89
90 err = x->outer_mode->afinfo->extract_input(x, skb);
91 if (err)
92 return err;
93
Kazunori MIYAZAWAdf9dcb42008-03-24 14:51:51 -070094 if (x->sel.family == AF_UNSPEC) {
95 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
96 if (inner_mode == NULL)
97 return -EAFNOSUPPORT;
98 }
99
100 skb->protocol = inner_mode->afinfo->eth_proto;
101 return inner_mode->input2(x, skb);
Herbert Xu227620e2007-11-13 21:41:28 -0800102}
103EXPORT_SYMBOL(xfrm_prepare_input);
104
Herbert Xu716062f2007-11-13 21:44:23 -0800105int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
106{
Alexey Dobriyanbd235e32008-11-25 17:37:56 -0800107 struct net *net = dev_net(skb->dev);
Herbert Xu716062f2007-11-13 21:44:23 -0800108 int err;
109 __be32 seq;
Herbert Xu716062f2007-11-13 21:44:23 -0800110 struct xfrm_state *x;
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800111 xfrm_address_t *daddr;
Kazunori MIYAZAWAdf9dcb42008-03-24 14:51:51 -0700112 struct xfrm_mode *inner_mode;
Herbert Xu2fcb45b2007-12-03 22:54:12 -0800113 unsigned int family;
Herbert Xu716062f2007-11-13 21:44:23 -0800114 int decaps = 0;
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800115 int async = 0;
116
117 /* A negative encap_type indicates async resumption. */
118 if (encap_type < 0) {
119 async = 1;
Herbert Xu00501122007-12-11 01:53:43 -0800120 x = xfrm_input_state(skb);
Herbert Xub318e0e2008-02-12 22:50:35 -0800121 seq = XFRM_SKB_CB(skb)->seq.input;
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800122 goto resume;
123 }
Herbert Xu716062f2007-11-13 21:44:23 -0800124
Herbert Xub2aa5e92007-11-13 21:44:55 -0800125 /* Allocate new secpath or COW existing one. */
126 if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
127 struct sec_path *sp;
128
129 sp = secpath_dup(skb->sp);
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800130 if (!sp) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800131 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
Herbert Xub2aa5e92007-11-13 21:44:55 -0800132 goto drop;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800133 }
Herbert Xub2aa5e92007-11-13 21:44:55 -0800134 if (skb->sp)
135 secpath_put(skb->sp);
136 skb->sp = sp;
137 }
138
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800139 daddr = (xfrm_address_t *)(skb_network_header(skb) +
140 XFRM_SPI_SKB_CB(skb)->daddroff);
Herbert Xu2fcb45b2007-12-03 22:54:12 -0800141 family = XFRM_SPI_SKB_CB(skb)->family;
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800142
Herbert Xu716062f2007-11-13 21:44:23 -0800143 seq = 0;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800144 if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800145 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
Herbert Xu716062f2007-11-13 21:44:23 -0800146 goto drop;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800147 }
Herbert Xu716062f2007-11-13 21:44:23 -0800148
149 do {
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800150 if (skb->sp->len == XFRM_MAX_DEPTH) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800151 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
Herbert Xu716062f2007-11-13 21:44:23 -0800152 goto drop;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800153 }
Herbert Xu716062f2007-11-13 21:44:23 -0800154
Alexey Dobriyanbd235e32008-11-25 17:37:56 -0800155 x = xfrm_state_lookup(net, daddr, spi, nexthdr, family);
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800156 if (x == NULL) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800157 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
Paul Mooreafeb14b2007-12-21 14:58:11 -0800158 xfrm_audit_state_notfound(skb, family, spi, seq);
Herbert Xu716062f2007-11-13 21:44:23 -0800159 goto drop;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800160 }
Herbert Xu716062f2007-11-13 21:44:23 -0800161
Herbert Xub2aa5e92007-11-13 21:44:55 -0800162 skb->sp->xvec[skb->sp->len++] = x;
163
Herbert Xu716062f2007-11-13 21:44:23 -0800164 spin_lock(&x->lock);
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800165 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800166 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEINVALID);
Herbert Xu716062f2007-11-13 21:44:23 -0800167 goto drop_unlock;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800168 }
Herbert Xu716062f2007-11-13 21:44:23 -0800169
David S. Miller3de77cf2008-12-18 19:23:56 -0800170 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
171 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
172 goto drop_unlock;
173 }
174
Paul Mooreafeb14b2007-12-21 14:58:11 -0800175 if (x->props.replay_window && xfrm_replay_check(x, skb, seq)) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800176 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
Herbert Xu716062f2007-11-13 21:44:23 -0800177 goto drop_unlock;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800178 }
Herbert Xu716062f2007-11-13 21:44:23 -0800179
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800180 if (xfrm_state_check_expire(x)) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800181 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
Herbert Xu716062f2007-11-13 21:44:23 -0800182 goto drop_unlock;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800183 }
Herbert Xu716062f2007-11-13 21:44:23 -0800184
Herbert Xu0ebea8e2007-11-13 21:45:58 -0800185 spin_unlock(&x->lock);
186
Herbert Xub318e0e2008-02-12 22:50:35 -0800187 XFRM_SKB_CB(skb)->seq.input = seq;
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800188
Herbert Xu716062f2007-11-13 21:44:23 -0800189 nexthdr = x->type->input(x, skb);
Herbert Xu0ebea8e2007-11-13 21:45:58 -0800190
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800191 if (nexthdr == -EINPROGRESS)
192 return 0;
193
194resume:
Herbert Xu0ebea8e2007-11-13 21:45:58 -0800195 spin_lock(&x->lock);
Herbert Xu668dc8a2007-12-16 15:55:02 -0800196 if (nexthdr <= 0) {
Herbert Xu9dd32452007-12-30 21:10:30 -0800197 if (nexthdr == -EBADMSG) {
198 xfrm_audit_state_icvfail(x, skb,
199 x->type->proto);
Herbert Xu668dc8a2007-12-16 15:55:02 -0800200 x->stats.integrity_failed++;
Herbert Xu9dd32452007-12-30 21:10:30 -0800201 }
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800202 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
Herbert Xu716062f2007-11-13 21:44:23 -0800203 goto drop_unlock;
Herbert Xu668dc8a2007-12-16 15:55:02 -0800204 }
Herbert Xu716062f2007-11-13 21:44:23 -0800205
Herbert Xu716062f2007-11-13 21:44:23 -0800206 /* only the first xfrm gets the encap type */
207 encap_type = 0;
208
209 if (x->props.replay_window)
210 xfrm_replay_advance(x, seq);
211
212 x->curlft.bytes += skb->len;
213 x->curlft.packets++;
214
215 spin_unlock(&x->lock);
216
Herbert Xu60d5fcf2007-11-19 18:47:58 -0800217 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
218
Kazunori MIYAZAWAdf9dcb42008-03-24 14:51:51 -0700219 inner_mode = x->inner_mode;
220
221 if (x->sel.family == AF_UNSPEC) {
222 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
223 if (inner_mode == NULL)
224 goto drop;
225 }
226
227 if (inner_mode->input(x, skb)) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800228 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
Herbert Xu716062f2007-11-13 21:44:23 -0800229 goto drop;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800230 }
Herbert Xu716062f2007-11-13 21:44:23 -0800231
232 if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) {
233 decaps = 1;
234 break;
235 }
236
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800237 /*
238 * We need the inner address. However, we only get here for
239 * transport mode so the outer address is identical.
240 */
241 daddr = &x->id.daddr;
Herbert Xu2fcb45b2007-12-03 22:54:12 -0800242 family = x->outer_mode->afinfo->family;
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800243
Herbert Xu716062f2007-11-13 21:44:23 -0800244 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800245 if (err < 0) {
Alexey Dobriyan59c99402008-11-25 17:59:52 -0800246 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
Herbert Xu716062f2007-11-13 21:44:23 -0800247 goto drop;
Masahide NAKAMURA0aa64772007-12-20 20:43:36 -0800248 }
Herbert Xu716062f2007-11-13 21:44:23 -0800249 } while (!err);
250
Herbert Xu716062f2007-11-13 21:44:23 -0800251 nf_reset(skb);
252
253 if (decaps) {
254 dst_release(skb->dst);
255 skb->dst = NULL;
256 netif_rx(skb);
257 return 0;
258 } else {
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800259 return x->inner_mode->afinfo->transport_finish(skb, async);
Herbert Xu716062f2007-11-13 21:44:23 -0800260 }
261
262drop_unlock:
263 spin_unlock(&x->lock);
Herbert Xu716062f2007-11-13 21:44:23 -0800264drop:
Herbert Xu716062f2007-11-13 21:44:23 -0800265 kfree_skb(skb);
266 return 0;
267}
268EXPORT_SYMBOL(xfrm_input);
269
Herbert Xu1bf06cd2007-11-19 18:50:17 -0800270int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
271{
272 return xfrm_input(skb, nexthdr, 0, -1);
273}
274EXPORT_SYMBOL(xfrm_input_resume);
275
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276void __init xfrm_input_init(void)
277{
278 secpath_cachep = kmem_cache_create("secpath_cache",
279 sizeof(struct sec_path),
Alexey Dobriyane5d679f332006-08-26 19:25:52 -0700280 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
Paul Mundt20c2df82007-07-20 10:11:58 +0900281 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282}