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> | |
16 | ||
e18b890b | 17 | static struct kmem_cache *secpath_cachep __read_mostly; |
1da177e4 LT |
18 | |
19 | void __secpath_destroy(struct sec_path *sp) | |
20 | { | |
21 | int i; | |
22 | for (i = 0; i < sp->len; i++) | |
dbe5b4aa | 23 | xfrm_state_put(sp->xvec[i]); |
1da177e4 LT |
24 | kmem_cache_free(secpath_cachep, sp); |
25 | } | |
26 | EXPORT_SYMBOL(__secpath_destroy); | |
27 | ||
28 | struct sec_path *secpath_dup(struct sec_path *src) | |
29 | { | |
30 | struct sec_path *sp; | |
31 | ||
54e6ecb2 | 32 | sp = kmem_cache_alloc(secpath_cachep, GFP_ATOMIC); |
1da177e4 LT |
33 | 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++) | |
dbe5b4aa | 42 | xfrm_state_hold(sp->xvec[i]); |
1da177e4 LT |
43 | } |
44 | atomic_set(&sp->refcnt, 1); | |
45 | return sp; | |
46 | } | |
47 | EXPORT_SYMBOL(secpath_dup); | |
48 | ||
49 | /* Fetch spi and seq from ipsec header */ | |
50 | ||
6067b2ba | 51 | int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq) |
1da177e4 LT |
52 | { |
53 | int offset, offset_seq; | |
44072500 | 54 | int hlen; |
1da177e4 LT |
55 | |
56 | switch (nexthdr) { | |
57 | case IPPROTO_AH: | |
44072500 | 58 | hlen = sizeof(struct ip_auth_hdr); |
1da177e4 LT |
59 | offset = offsetof(struct ip_auth_hdr, spi); |
60 | offset_seq = offsetof(struct ip_auth_hdr, seq_no); | |
61 | break; | |
62 | case IPPROTO_ESP: | |
44072500 | 63 | hlen = sizeof(struct ip_esp_hdr); |
1da177e4 LT |
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; | |
9c70220b | 70 | *spi = htonl(ntohs(*(__be16*)(skb_transport_header(skb) + 2))); |
1da177e4 LT |
71 | *seq = 0; |
72 | return 0; | |
73 | default: | |
74 | return 1; | |
75 | } | |
76 | ||
44072500 | 77 | if (!pskb_may_pull(skb, hlen)) |
1da177e4 LT |
78 | return -EINVAL; |
79 | ||
9c70220b ACM |
80 | *spi = *(__be32*)(skb_transport_header(skb) + offset); |
81 | *seq = *(__be32*)(skb_transport_header(skb) + offset_seq); | |
1da177e4 LT |
82 | return 0; |
83 | } | |
1da177e4 | 84 | |
227620e2 HX |
85 | int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb) |
86 | { | |
df9dcb45 | 87 | struct xfrm_mode *inner_mode = x->inner_mode; |
227620e2 HX |
88 | int err; |
89 | ||
90 | err = x->outer_mode->afinfo->extract_input(x, skb); | |
91 | if (err) | |
92 | return err; | |
93 | ||
df9dcb45 KM |
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; | |
98 | } | |
99 | ||
100 | skb->protocol = inner_mode->afinfo->eth_proto; | |
101 | return inner_mode->input2(x, skb); | |
227620e2 HX |
102 | } |
103 | EXPORT_SYMBOL(xfrm_prepare_input); | |
104 | ||
716062fd HX |
105 | int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) |
106 | { | |
bd235e3c | 107 | struct net *net = dev_net(skb->dev); |
716062fd HX |
108 | int err; |
109 | __be32 seq; | |
716062fd | 110 | struct xfrm_state *x; |
1bf06cd2 | 111 | xfrm_address_t *daddr; |
df9dcb45 | 112 | struct xfrm_mode *inner_mode; |
2fcb45b6 | 113 | unsigned int family; |
716062fd | 114 | int decaps = 0; |
1bf06cd2 HX |
115 | int async = 0; |
116 | ||
117 | /* A negative encap_type indicates async resumption. */ | |
118 | if (encap_type < 0) { | |
119 | async = 1; | |
00501121 | 120 | x = xfrm_input_state(skb); |
b318e0e4 | 121 | seq = XFRM_SKB_CB(skb)->seq.input; |
1bf06cd2 HX |
122 | goto resume; |
123 | } | |
716062fd | 124 | |
b2aa5e9d HX |
125 | /* 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); | |
0aa64774 | 130 | if (!sp) { |
59c9940e | 131 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR); |
b2aa5e9d | 132 | goto drop; |
0aa64774 | 133 | } |
b2aa5e9d HX |
134 | if (skb->sp) |
135 | secpath_put(skb->sp); | |
136 | skb->sp = sp; | |
137 | } | |
138 | ||
1bf06cd2 HX |
139 | daddr = (xfrm_address_t *)(skb_network_header(skb) + |
140 | XFRM_SPI_SKB_CB(skb)->daddroff); | |
2fcb45b6 | 141 | family = XFRM_SPI_SKB_CB(skb)->family; |
1bf06cd2 | 142 | |
716062fd | 143 | seq = 0; |
0aa64774 | 144 | if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) { |
59c9940e | 145 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); |
716062fd | 146 | goto drop; |
0aa64774 | 147 | } |
716062fd HX |
148 | |
149 | do { | |
0aa64774 | 150 | if (skb->sp->len == XFRM_MAX_DEPTH) { |
59c9940e | 151 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); |
716062fd | 152 | goto drop; |
0aa64774 | 153 | } |
716062fd | 154 | |
bd235e3c | 155 | x = xfrm_state_lookup(net, daddr, spi, nexthdr, family); |
0aa64774 | 156 | if (x == NULL) { |
59c9940e | 157 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); |
afeb14b4 | 158 | xfrm_audit_state_notfound(skb, family, spi, seq); |
716062fd | 159 | goto drop; |
0aa64774 | 160 | } |
716062fd | 161 | |
b2aa5e9d HX |
162 | skb->sp->xvec[skb->sp->len++] = x; |
163 | ||
716062fd | 164 | spin_lock(&x->lock); |
0aa64774 | 165 | if (unlikely(x->km.state != XFRM_STATE_VALID)) { |
59c9940e | 166 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEINVALID); |
716062fd | 167 | goto drop_unlock; |
0aa64774 | 168 | } |
716062fd | 169 | |
3de77cf2 DM |
170 | if ((x->encap ? x->encap->encap_type : 0) != encap_type) { |
171 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); | |
172 | goto drop_unlock; | |
173 | } | |
174 | ||
afeb14b4 | 175 | if (x->props.replay_window && xfrm_replay_check(x, skb, seq)) { |
59c9940e | 176 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR); |
716062fd | 177 | goto drop_unlock; |
0aa64774 | 178 | } |
716062fd | 179 | |
0aa64774 | 180 | if (xfrm_state_check_expire(x)) { |
59c9940e | 181 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED); |
716062fd | 182 | goto drop_unlock; |
0aa64774 | 183 | } |
716062fd | 184 | |
0ebea8ef HX |
185 | spin_unlock(&x->lock); |
186 | ||
b318e0e4 | 187 | XFRM_SKB_CB(skb)->seq.input = seq; |
1bf06cd2 | 188 | |
716062fd | 189 | nexthdr = x->type->input(x, skb); |
0ebea8ef | 190 | |
1bf06cd2 HX |
191 | if (nexthdr == -EINPROGRESS) |
192 | return 0; | |
193 | ||
194 | resume: | |
0ebea8ef | 195 | spin_lock(&x->lock); |
668dc8af | 196 | if (nexthdr <= 0) { |
9dd3245a HX |
197 | if (nexthdr == -EBADMSG) { |
198 | xfrm_audit_state_icvfail(x, skb, | |
199 | x->type->proto); | |
668dc8af | 200 | x->stats.integrity_failed++; |
9dd3245a | 201 | } |
59c9940e | 202 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR); |
716062fd | 203 | goto drop_unlock; |
668dc8af | 204 | } |
716062fd | 205 | |
716062fd HX |
206 | /* 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 | ||
60d5fcfb HX |
217 | XFRM_MODE_SKB_CB(skb)->protocol = nexthdr; |
218 | ||
df9dcb45 KM |
219 | 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)) { | |
59c9940e | 228 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR); |
716062fd | 229 | goto drop; |
0aa64774 | 230 | } |
716062fd HX |
231 | |
232 | if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) { | |
233 | decaps = 1; | |
234 | break; | |
235 | } | |
236 | ||
1bf06cd2 HX |
237 | /* |
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; | |
2fcb45b6 | 242 | family = x->outer_mode->afinfo->family; |
1bf06cd2 | 243 | |
716062fd | 244 | err = xfrm_parse_spi(skb, nexthdr, &spi, &seq); |
0aa64774 | 245 | if (err < 0) { |
59c9940e | 246 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); |
716062fd | 247 | goto drop; |
0aa64774 | 248 | } |
716062fd HX |
249 | } while (!err); |
250 | ||
716062fd HX |
251 | nf_reset(skb); |
252 | ||
253 | if (decaps) { | |
adf30907 | 254 | skb_dst_drop(skb); |
716062fd HX |
255 | netif_rx(skb); |
256 | return 0; | |
257 | } else { | |
1bf06cd2 | 258 | return x->inner_mode->afinfo->transport_finish(skb, async); |
716062fd HX |
259 | } |
260 | ||
261 | drop_unlock: | |
262 | spin_unlock(&x->lock); | |
716062fd | 263 | drop: |
716062fd HX |
264 | kfree_skb(skb); |
265 | return 0; | |
266 | } | |
267 | EXPORT_SYMBOL(xfrm_input); | |
268 | ||
1bf06cd2 HX |
269 | int xfrm_input_resume(struct sk_buff *skb, int nexthdr) |
270 | { | |
271 | return xfrm_input(skb, nexthdr, 0, -1); | |
272 | } | |
273 | EXPORT_SYMBOL(xfrm_input_resume); | |
274 | ||
1da177e4 LT |
275 | void __init xfrm_input_init(void) |
276 | { | |
277 | secpath_cachep = kmem_cache_create("secpath_cache", | |
278 | sizeof(struct sec_path), | |
e5d679f3 | 279 | 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, |
20c2df83 | 280 | NULL); |
1da177e4 | 281 | } |