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; | |
103 | struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH]; | |
104 | struct xfrm_state *x; | |
105 | int xfrm_nr = 0; | |
106 | int decaps = 0; | |
107 | unsigned int nhoff = XFRM_SPI_SKB_CB(skb)->nhoff; | |
108 | unsigned int daddroff = XFRM_SPI_SKB_CB(skb)->daddroff; | |
109 | ||
110 | seq = 0; | |
111 | if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) | |
112 | goto drop; | |
113 | ||
114 | do { | |
115 | if (xfrm_nr == XFRM_MAX_DEPTH) | |
116 | goto drop; | |
117 | ||
118 | x = xfrm_state_lookup((xfrm_address_t *) | |
119 | (skb_network_header(skb) + daddroff), | |
120 | spi, nexthdr, AF_INET); | |
121 | if (x == NULL) | |
122 | goto drop; | |
123 | ||
124 | spin_lock(&x->lock); | |
125 | if (unlikely(x->km.state != XFRM_STATE_VALID)) | |
126 | goto drop_unlock; | |
127 | ||
128 | if ((x->encap ? x->encap->encap_type : 0) != encap_type) | |
129 | goto drop_unlock; | |
130 | ||
131 | if (x->props.replay_window && xfrm_replay_check(x, seq)) | |
132 | goto drop_unlock; | |
133 | ||
134 | if (xfrm_state_check_expire(x)) | |
135 | goto drop_unlock; | |
136 | ||
137 | nexthdr = x->type->input(x, skb); | |
138 | if (nexthdr <= 0) | |
139 | goto drop_unlock; | |
140 | ||
141 | skb_network_header(skb)[nhoff] = nexthdr; | |
142 | ||
143 | /* only the first xfrm gets the encap type */ | |
144 | encap_type = 0; | |
145 | ||
146 | if (x->props.replay_window) | |
147 | xfrm_replay_advance(x, seq); | |
148 | ||
149 | x->curlft.bytes += skb->len; | |
150 | x->curlft.packets++; | |
151 | ||
152 | spin_unlock(&x->lock); | |
153 | ||
154 | xfrm_vec[xfrm_nr++] = x; | |
155 | ||
156 | if (x->inner_mode->input(x, skb)) | |
157 | goto drop; | |
158 | ||
159 | if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) { | |
160 | decaps = 1; | |
161 | break; | |
162 | } | |
163 | ||
164 | err = xfrm_parse_spi(skb, nexthdr, &spi, &seq); | |
165 | if (err < 0) | |
166 | goto drop; | |
167 | } while (!err); | |
168 | ||
169 | /* Allocate new secpath or COW existing one. */ | |
170 | ||
171 | if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) { | |
172 | struct sec_path *sp; | |
173 | sp = secpath_dup(skb->sp); | |
174 | if (!sp) | |
175 | goto drop; | |
176 | if (skb->sp) | |
177 | secpath_put(skb->sp); | |
178 | skb->sp = sp; | |
179 | } | |
180 | if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH) | |
181 | goto drop; | |
182 | ||
183 | memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec, | |
184 | xfrm_nr * sizeof(xfrm_vec[0])); | |
185 | skb->sp->len += xfrm_nr; | |
186 | ||
187 | nf_reset(skb); | |
188 | ||
189 | if (decaps) { | |
190 | dst_release(skb->dst); | |
191 | skb->dst = NULL; | |
192 | netif_rx(skb); | |
193 | return 0; | |
194 | } else { | |
195 | return x->inner_mode->afinfo->transport_finish(skb, 0); | |
196 | } | |
197 | ||
198 | drop_unlock: | |
199 | spin_unlock(&x->lock); | |
200 | xfrm_state_put(x); | |
201 | drop: | |
202 | while (--xfrm_nr >= 0) | |
203 | xfrm_state_put(xfrm_vec[xfrm_nr]); | |
204 | ||
205 | kfree_skb(skb); | |
206 | return 0; | |
207 | } | |
208 | EXPORT_SYMBOL(xfrm_input); | |
209 | ||
1da177e4 LT |
210 | void __init xfrm_input_init(void) |
211 | { | |
212 | secpath_cachep = kmem_cache_create("secpath_cache", | |
213 | sizeof(struct sec_path), | |
e5d679f3 | 214 | 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, |
20c2df83 | 215 | NULL); |
1da177e4 | 216 | } |