Linux 2.6.26-rc5
[linux-2.6/openmoko-kernel/knife-kernel.git] / net / xfrm / xfrm_input.c
blob75279402ccf46f085f249cd65eda2a9e69db40a2
1 /*
2 * xfrm_input.c
4 * Changes:
5 * YOSHIFUJI Hideaki @USAGI
6 * Split up af-specific portion
8 */
10 #include <linux/slab.h>
11 #include <linux/module.h>
12 #include <linux/netdevice.h>
13 #include <net/dst.h>
14 #include <net/ip.h>
15 #include <net/xfrm.h>
17 static struct kmem_cache *secpath_cachep __read_mostly;
19 void __secpath_destroy(struct sec_path *sp)
21 int i;
22 for (i = 0; i < sp->len; i++)
23 xfrm_state_put(sp->xvec[i]);
24 kmem_cache_free(secpath_cachep, sp);
26 EXPORT_SYMBOL(__secpath_destroy);
28 struct sec_path *secpath_dup(struct sec_path *src)
30 struct sec_path *sp;
32 sp = kmem_cache_alloc(secpath_cachep, GFP_ATOMIC);
33 if (!sp)
34 return NULL;
36 sp->len = 0;
37 if (src) {
38 int i;
40 memcpy(sp, src, sizeof(*sp));
41 for (i = 0; i < sp->len; i++)
42 xfrm_state_hold(sp->xvec[i]);
44 atomic_set(&sp->refcnt, 1);
45 return sp;
47 EXPORT_SYMBOL(secpath_dup);
49 /* Fetch spi and seq from ipsec header */
51 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
53 int offset, offset_seq;
54 int hlen;
56 switch (nexthdr) {
57 case IPPROTO_AH:
58 hlen = sizeof(struct ip_auth_hdr);
59 offset = offsetof(struct ip_auth_hdr, spi);
60 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
61 break;
62 case IPPROTO_ESP:
63 hlen = sizeof(struct ip_esp_hdr);
64 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;
70 *spi = htonl(ntohs(*(__be16*)(skb_transport_header(skb) + 2)));
71 *seq = 0;
72 return 0;
73 default:
74 return 1;
77 if (!pskb_may_pull(skb, hlen))
78 return -EINVAL;
80 *spi = *(__be32*)(skb_transport_header(skb) + offset);
81 *seq = *(__be32*)(skb_transport_header(skb) + offset_seq);
82 return 0;
85 int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
87 struct xfrm_mode *inner_mode = x->inner_mode;
88 int err;
90 err = x->outer_mode->afinfo->extract_input(x, skb);
91 if (err)
92 return err;
94 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;
100 skb->protocol = inner_mode->afinfo->eth_proto;
101 return inner_mode->input2(x, skb);
103 EXPORT_SYMBOL(xfrm_prepare_input);
105 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
107 int err;
108 __be32 seq;
109 struct xfrm_state *x;
110 xfrm_address_t *daddr;
111 struct xfrm_mode *inner_mode;
112 unsigned int family;
113 int decaps = 0;
114 int async = 0;
116 /* A negative encap_type indicates async resumption. */
117 if (encap_type < 0) {
118 async = 1;
119 x = xfrm_input_state(skb);
120 seq = XFRM_SKB_CB(skb)->seq.input;
121 goto resume;
124 /* Allocate new secpath or COW existing one. */
125 if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
126 struct sec_path *sp;
128 sp = secpath_dup(skb->sp);
129 if (!sp) {
130 XFRM_INC_STATS(LINUX_MIB_XFRMINERROR);
131 goto drop;
133 if (skb->sp)
134 secpath_put(skb->sp);
135 skb->sp = sp;
138 daddr = (xfrm_address_t *)(skb_network_header(skb) +
139 XFRM_SPI_SKB_CB(skb)->daddroff);
140 family = XFRM_SPI_SKB_CB(skb)->family;
142 seq = 0;
143 if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
144 XFRM_INC_STATS(LINUX_MIB_XFRMINHDRERROR);
145 goto drop;
148 do {
149 if (skb->sp->len == XFRM_MAX_DEPTH) {
150 XFRM_INC_STATS(LINUX_MIB_XFRMINBUFFERERROR);
151 goto drop;
154 x = xfrm_state_lookup(daddr, spi, nexthdr, family);
155 if (x == NULL) {
156 XFRM_INC_STATS(LINUX_MIB_XFRMINNOSTATES);
157 xfrm_audit_state_notfound(skb, family, spi, seq);
158 goto drop;
161 skb->sp->xvec[skb->sp->len++] = x;
163 spin_lock(&x->lock);
164 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
165 XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEINVALID);
166 goto drop_unlock;
169 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
170 XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEMISMATCH);
171 goto drop_unlock;
174 if (x->props.replay_window && xfrm_replay_check(x, skb, seq)) {
175 XFRM_INC_STATS(LINUX_MIB_XFRMINSTATESEQERROR);
176 goto drop_unlock;
179 if (xfrm_state_check_expire(x)) {
180 XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEEXPIRED);
181 goto drop_unlock;
184 spin_unlock(&x->lock);
186 XFRM_SKB_CB(skb)->seq.input = seq;
188 nexthdr = x->type->input(x, skb);
190 if (nexthdr == -EINPROGRESS)
191 return 0;
193 resume:
194 spin_lock(&x->lock);
195 if (nexthdr <= 0) {
196 if (nexthdr == -EBADMSG) {
197 xfrm_audit_state_icvfail(x, skb,
198 x->type->proto);
199 x->stats.integrity_failed++;
201 XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEPROTOERROR);
202 goto drop_unlock;
205 /* only the first xfrm gets the encap type */
206 encap_type = 0;
208 if (x->props.replay_window)
209 xfrm_replay_advance(x, seq);
211 x->curlft.bytes += skb->len;
212 x->curlft.packets++;
214 spin_unlock(&x->lock);
216 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
218 inner_mode = x->inner_mode;
220 if (x->sel.family == AF_UNSPEC) {
221 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
222 if (inner_mode == NULL)
223 goto drop;
226 if (inner_mode->input(x, skb)) {
227 XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEMODEERROR);
228 goto drop;
231 if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) {
232 decaps = 1;
233 break;
237 * We need the inner address. However, we only get here for
238 * transport mode so the outer address is identical.
240 daddr = &x->id.daddr;
241 family = x->outer_mode->afinfo->family;
243 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
244 if (err < 0) {
245 XFRM_INC_STATS(LINUX_MIB_XFRMINHDRERROR);
246 goto drop;
248 } while (!err);
250 nf_reset(skb);
252 if (decaps) {
253 dst_release(skb->dst);
254 skb->dst = NULL;
255 netif_rx(skb);
256 return 0;
257 } else {
258 return x->inner_mode->afinfo->transport_finish(skb, async);
261 drop_unlock:
262 spin_unlock(&x->lock);
263 drop:
264 kfree_skb(skb);
265 return 0;
267 EXPORT_SYMBOL(xfrm_input);
269 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
271 return xfrm_input(skb, nexthdr, 0, -1);
273 EXPORT_SYMBOL(xfrm_input_resume);
275 void __init xfrm_input_init(void)
277 secpath_cachep = kmem_cache_create("secpath_cache",
278 sizeof(struct sec_path),
279 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
280 NULL);