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 | } | |
84 | EXPORT_SYMBOL(xfrm_parse_spi); | |
85 | ||
227620e2 HX |
86 | int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb) |
87 | { | |
88 | int err; | |
89 | ||
90 | err = x->outer_mode->afinfo->extract_input(x, skb); | |
91 | if (err) | |
92 | return err; | |
93 | ||
94 | skb->protocol = x->inner_mode->afinfo->eth_proto; | |
95 | return x->inner_mode->input2(x, skb); | |
96 | } | |
97 | EXPORT_SYMBOL(xfrm_prepare_input); | |
98 | ||
716062fd HX |
99 | int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) |
100 | { | |
101 | int err; | |
102 | __be32 seq; | |
716062fd | 103 | struct xfrm_state *x; |
1bf06cd2 | 104 | xfrm_address_t *daddr; |
2fcb45b6 | 105 | unsigned int family; |
716062fd | 106 | int decaps = 0; |
1bf06cd2 HX |
107 | int async = 0; |
108 | ||
109 | /* A negative encap_type indicates async resumption. */ | |
110 | if (encap_type < 0) { | |
111 | async = 1; | |
00501121 | 112 | x = xfrm_input_state(skb); |
1bf06cd2 HX |
113 | seq = XFRM_SKB_CB(skb)->seq; |
114 | goto resume; | |
115 | } | |
716062fd | 116 | |
b2aa5e9d HX |
117 | /* Allocate new secpath or COW existing one. */ |
118 | if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) { | |
119 | struct sec_path *sp; | |
120 | ||
121 | sp = secpath_dup(skb->sp); | |
0aa64774 MN |
122 | if (!sp) { |
123 | XFRM_INC_STATS(LINUX_MIB_XFRMINERROR); | |
b2aa5e9d | 124 | goto drop; |
0aa64774 | 125 | } |
b2aa5e9d HX |
126 | if (skb->sp) |
127 | secpath_put(skb->sp); | |
128 | skb->sp = sp; | |
129 | } | |
130 | ||
1bf06cd2 HX |
131 | daddr = (xfrm_address_t *)(skb_network_header(skb) + |
132 | XFRM_SPI_SKB_CB(skb)->daddroff); | |
2fcb45b6 | 133 | family = XFRM_SPI_SKB_CB(skb)->family; |
1bf06cd2 | 134 | |
716062fd | 135 | seq = 0; |
0aa64774 MN |
136 | if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) { |
137 | XFRM_INC_STATS(LINUX_MIB_XFRMINHDRERROR); | |
716062fd | 138 | goto drop; |
0aa64774 | 139 | } |
716062fd HX |
140 | |
141 | do { | |
0aa64774 MN |
142 | if (skb->sp->len == XFRM_MAX_DEPTH) { |
143 | XFRM_INC_STATS(LINUX_MIB_XFRMINBUFFERERROR); | |
716062fd | 144 | goto drop; |
0aa64774 | 145 | } |
716062fd | 146 | |
2fcb45b6 | 147 | x = xfrm_state_lookup(daddr, spi, nexthdr, family); |
0aa64774 MN |
148 | if (x == NULL) { |
149 | XFRM_INC_STATS(LINUX_MIB_XFRMINNOSTATES); | |
afeb14b4 | 150 | xfrm_audit_state_notfound(skb, family, spi, seq); |
716062fd | 151 | goto drop; |
0aa64774 | 152 | } |
716062fd | 153 | |
b2aa5e9d HX |
154 | skb->sp->xvec[skb->sp->len++] = x; |
155 | ||
716062fd | 156 | spin_lock(&x->lock); |
0aa64774 MN |
157 | if (unlikely(x->km.state != XFRM_STATE_VALID)) { |
158 | XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEINVALID); | |
716062fd | 159 | goto drop_unlock; |
0aa64774 | 160 | } |
716062fd | 161 | |
0aa64774 MN |
162 | if ((x->encap ? x->encap->encap_type : 0) != encap_type) { |
163 | XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEINVALID); | |
716062fd | 164 | goto drop_unlock; |
0aa64774 | 165 | } |
716062fd | 166 | |
afeb14b4 | 167 | if (x->props.replay_window && xfrm_replay_check(x, skb, seq)) { |
0aa64774 | 168 | XFRM_INC_STATS(LINUX_MIB_XFRMINSEQOUTOFWINDOW); |
716062fd | 169 | goto drop_unlock; |
0aa64774 | 170 | } |
716062fd | 171 | |
0aa64774 MN |
172 | if (xfrm_state_check_expire(x)) { |
173 | XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEEXPIRED); | |
716062fd | 174 | goto drop_unlock; |
0aa64774 | 175 | } |
716062fd | 176 | |
0ebea8ef HX |
177 | spin_unlock(&x->lock); |
178 | ||
1bf06cd2 HX |
179 | XFRM_SKB_CB(skb)->seq = seq; |
180 | ||
716062fd | 181 | nexthdr = x->type->input(x, skb); |
0ebea8ef | 182 | |
1bf06cd2 HX |
183 | if (nexthdr == -EINPROGRESS) |
184 | return 0; | |
185 | ||
186 | resume: | |
0ebea8ef | 187 | spin_lock(&x->lock); |
668dc8af HX |
188 | if (nexthdr <= 0) { |
189 | if (nexthdr == -EBADMSG) | |
190 | x->stats.integrity_failed++; | |
0aa64774 | 191 | XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEPROTOERROR); |
716062fd | 192 | goto drop_unlock; |
668dc8af | 193 | } |
716062fd | 194 | |
716062fd HX |
195 | /* only the first xfrm gets the encap type */ |
196 | encap_type = 0; | |
197 | ||
198 | if (x->props.replay_window) | |
199 | xfrm_replay_advance(x, seq); | |
200 | ||
201 | x->curlft.bytes += skb->len; | |
202 | x->curlft.packets++; | |
203 | ||
204 | spin_unlock(&x->lock); | |
205 | ||
60d5fcfb HX |
206 | XFRM_MODE_SKB_CB(skb)->protocol = nexthdr; |
207 | ||
0aa64774 MN |
208 | if (x->inner_mode->input(x, skb)) { |
209 | XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEMODEERROR); | |
716062fd | 210 | goto drop; |
0aa64774 | 211 | } |
716062fd HX |
212 | |
213 | if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) { | |
214 | decaps = 1; | |
215 | break; | |
216 | } | |
217 | ||
1bf06cd2 HX |
218 | /* |
219 | * We need the inner address. However, we only get here for | |
220 | * transport mode so the outer address is identical. | |
221 | */ | |
222 | daddr = &x->id.daddr; | |
2fcb45b6 | 223 | family = x->outer_mode->afinfo->family; |
1bf06cd2 | 224 | |
716062fd | 225 | err = xfrm_parse_spi(skb, nexthdr, &spi, &seq); |
0aa64774 MN |
226 | if (err < 0) { |
227 | XFRM_INC_STATS(LINUX_MIB_XFRMINHDRERROR); | |
716062fd | 228 | goto drop; |
0aa64774 | 229 | } |
716062fd HX |
230 | } while (!err); |
231 | ||
716062fd HX |
232 | nf_reset(skb); |
233 | ||
234 | if (decaps) { | |
235 | dst_release(skb->dst); | |
236 | skb->dst = NULL; | |
237 | netif_rx(skb); | |
238 | return 0; | |
239 | } else { | |
1bf06cd2 | 240 | return x->inner_mode->afinfo->transport_finish(skb, async); |
716062fd HX |
241 | } |
242 | ||
243 | drop_unlock: | |
244 | spin_unlock(&x->lock); | |
716062fd | 245 | drop: |
716062fd HX |
246 | kfree_skb(skb); |
247 | return 0; | |
248 | } | |
249 | EXPORT_SYMBOL(xfrm_input); | |
250 | ||
1bf06cd2 HX |
251 | int xfrm_input_resume(struct sk_buff *skb, int nexthdr) |
252 | { | |
253 | return xfrm_input(skb, nexthdr, 0, -1); | |
254 | } | |
255 | EXPORT_SYMBOL(xfrm_input_resume); | |
256 | ||
1da177e4 LT |
257 | void __init xfrm_input_init(void) |
258 | { | |
259 | secpath_cachep = kmem_cache_create("secpath_cache", | |
260 | sizeof(struct sec_path), | |
e5d679f3 | 261 | 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, |
20c2df83 | 262 | NULL); |
1da177e4 | 263 | } |