blob: 66eb4968b9106e7199ec011cc71a08b4e37f02b8 [file] [log] [blame]
Herbert Xu6b7326c2006-07-30 15:41:01 +10001#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07002#include <linux/module.h>
3#include <net/ip.h>
4#include <net/xfrm.h>
5#include <net/esp.h>
6#include <asm/scatterlist.h>
7#include <linux/crypto.h>
Herbert Xua02a6422005-10-10 21:11:08 -07008#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07009#include <linux/pfkeyv2.h>
10#include <linux/random.h>
Herbert Xub7c65382007-10-09 13:33:35 -070011#include <linux/spinlock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <net/icmp.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020013#include <net/protocol.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <net/udp.h>
15
Linus Torvalds1da177e2005-04-16 15:20:36 -070016static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
17{
18 int err;
19 struct iphdr *top_iph;
20 struct ip_esp_hdr *esph;
Herbert Xu6b7326c2006-07-30 15:41:01 +100021 struct crypto_blkcipher *tfm;
22 struct blkcipher_desc desc;
Linus Torvalds1da177e2005-04-16 15:20:36 -070023 struct esp_data *esp;
24 struct sk_buff *trailer;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -070025 u8 *tail;
Linus Torvalds1da177e2005-04-16 15:20:36 -070026 int blksize;
27 int clen;
28 int alen;
29 int nfrags;
30
Herbert Xu7b277b12007-10-10 15:44:06 -070031 /* skb is pure payload to encrypt */
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
33 err = -ENOMEM;
34
35 /* Round to block size */
36 clen = skb->len;
37
38 esp = x->data;
39 alen = esp->auth.icv_trunc_len;
40 tfm = esp->conf.tfm;
Herbert Xu6b7326c2006-07-30 15:41:01 +100041 desc.tfm = tfm;
42 desc.flags = 0;
43 blksize = ALIGN(crypto_blkcipher_blocksize(tfm), 4);
Herbert Xua02a6422005-10-10 21:11:08 -070044 clen = ALIGN(clen + 2, blksize);
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 if (esp->conf.padlen)
Herbert Xua02a6422005-10-10 21:11:08 -070046 clen = ALIGN(clen, esp->conf.padlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48 if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0)
49 goto error;
50
51 /* Fill padding... */
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -070052 tail = skb_tail_pointer(trailer);
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 do {
54 int i;
55 for (i=0; i<clen-skb->len - 2; i++)
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -070056 tail[i] = i + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -070057 } while (0);
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -070058 tail[clen - skb->len - 2] = (clen - skb->len) - 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 pskb_put(skb, trailer, clen - skb->len);
60
Herbert Xu7b277b12007-10-10 15:44:06 -070061 skb_push(skb, -skb_network_offset(skb));
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -070062 top_iph = ip_hdr(skb);
Herbert Xu87bdc482007-10-10 15:45:25 -070063 esph = ip_esp_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 top_iph->tot_len = htons(skb->len + alen);
Herbert Xu37fedd32007-10-10 15:44:44 -070065 *(skb_tail_pointer(trailer) - 1) = *skb_mac_header(skb);
66 *skb_mac_header(skb) = IPPROTO_ESP;
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
Herbert Xub7c65382007-10-09 13:33:35 -070068 spin_lock_bh(&x->lock);
69
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 /* this is non-NULL only with UDP Encapsulation */
71 if (x->encap) {
72 struct xfrm_encap_tmpl *encap = x->encap;
73 struct udphdr *uh;
Al Virod5a0a1e2006-11-08 00:23:14 -080074 __be32 *udpdata32;
Linus Torvalds1da177e2005-04-16 15:20:36 -070075
76 uh = (struct udphdr *)esph;
77 uh->source = encap->encap_sport;
78 uh->dest = encap->encap_dport;
79 uh->len = htons(skb->len + alen - top_iph->ihl*4);
80 uh->check = 0;
81
82 switch (encap->encap_type) {
83 default:
84 case UDP_ENCAP_ESPINUDP:
85 esph = (struct ip_esp_hdr *)(uh + 1);
86 break;
87 case UDP_ENCAP_ESPINUDP_NON_IKE:
Al Virod5a0a1e2006-11-08 00:23:14 -080088 udpdata32 = (__be32 *)(uh + 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 udpdata32[0] = udpdata32[1] = 0;
90 esph = (struct ip_esp_hdr *)(udpdata32 + 2);
91 break;
92 }
93
Herbert Xu37fedd32007-10-10 15:44:44 -070094 *skb_mac_header(skb) = IPPROTO_UDP;
95 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
97 esph->spi = x->id.spi;
Herbert Xu436a0a42007-10-08 17:25:53 -070098 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099
David S. Millere4bec822006-09-22 15:17:35 -0700100 if (esp->conf.ivlen) {
101 if (unlikely(!esp->conf.ivinitted)) {
102 get_random_bytes(esp->conf.ivec, esp->conf.ivlen);
103 esp->conf.ivinitted = 1;
104 }
Herbert Xu6b7326c2006-07-30 15:41:01 +1000105 crypto_blkcipher_set_iv(tfm, esp->conf.ivec, esp->conf.ivlen);
David S. Millere4bec822006-09-22 15:17:35 -0700106 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107
108 do {
109 struct scatterlist *sg = &esp->sgbuf[0];
110
111 if (unlikely(nfrags > ESP_NUM_FAST_SG)) {
112 sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC);
113 if (!sg)
Herbert Xub7c65382007-10-09 13:33:35 -0700114 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 }
116 skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen);
Herbert Xu6b7326c2006-07-30 15:41:01 +1000117 err = crypto_blkcipher_encrypt(&desc, sg, sg, clen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 if (unlikely(sg != &esp->sgbuf[0]))
119 kfree(sg);
120 } while (0);
121
Herbert Xu6b7326c2006-07-30 15:41:01 +1000122 if (unlikely(err))
Herbert Xub7c65382007-10-09 13:33:35 -0700123 goto unlock;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000124
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 if (esp->conf.ivlen) {
Herbert Xu6b7326c2006-07-30 15:41:01 +1000126 memcpy(esph->enc_data, esp->conf.ivec, esp->conf.ivlen);
127 crypto_blkcipher_get_iv(tfm, esp->conf.ivec, esp->conf.ivlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 }
129
130 if (esp->auth.icv_full_len) {
Herbert Xu07d4ee52006-08-20 14:24:50 +1000131 err = esp_mac_digest(esp, skb, (u8 *)esph - skb->data,
132 sizeof(*esph) + esp->conf.ivlen + clen);
133 memcpy(pskb_put(skb, trailer, alen), esp->auth.work_icv, alen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 }
135
Herbert Xub7c65382007-10-09 13:33:35 -0700136unlock:
137 spin_unlock_bh(&x->lock);
138
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 ip_send_check(top_iph);
140
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141error:
142 return err;
143}
144
145/*
146 * Note: detecting truncated vs. non-truncated authentication data is very
147 * expensive, so we only support truncated data, which is the recommended
148 * and common case.
149 */
Herbert Xue6956332006-04-01 00:52:46 -0800150static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151{
152 struct iphdr *iph;
153 struct ip_esp_hdr *esph;
154 struct esp_data *esp = x->data;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000155 struct crypto_blkcipher *tfm = esp->conf.tfm;
156 struct blkcipher_desc desc = { .tfm = tfm };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 struct sk_buff *trailer;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000158 int blksize = ALIGN(crypto_blkcipher_blocksize(tfm), 4);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 int alen = esp->auth.icv_trunc_len;
Herbert Xu87bdc482007-10-10 15:45:25 -0700160 int elen = skb->len - sizeof(*esph) - esp->conf.ivlen - alen;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 int nfrags;
Herbert Xu31a4ab92006-05-27 23:06:13 -0700162 int ihl;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800163 u8 nexthdr[2];
164 struct scatterlist *sg;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800165 int padlen;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000166 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167
Herbert Xu87bdc482007-10-10 15:45:25 -0700168 if (!pskb_may_pull(skb, sizeof(*esph)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 goto out;
170
171 if (elen <= 0 || (elen & (blksize-1)))
172 goto out;
173
174 /* If integrity check is required, do this. */
175 if (esp->auth.icv_full_len) {
Herbert Xu07d4ee52006-08-20 14:24:50 +1000176 u8 sum[alen];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177
Herbert Xu07d4ee52006-08-20 14:24:50 +1000178 err = esp_mac_digest(esp, skb, 0, skb->len - alen);
179 if (err)
180 goto out;
181
182 if (skb_copy_bits(skb, skb->len - alen, sum, alen))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183 BUG();
184
Herbert Xu07d4ee52006-08-20 14:24:50 +1000185 if (unlikely(memcmp(esp->auth.work_icv, sum, alen))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 x->stats.integrity_failed++;
187 goto out;
188 }
189 }
190
191 if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0)
192 goto out;
193
194 skb->ip_summed = CHECKSUM_NONE;
195
Herbert Xu87bdc482007-10-10 15:45:25 -0700196 esph = (struct ip_esp_hdr *)skb->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197
198 /* Get ivec. This can be wrong, check against another impls. */
199 if (esp->conf.ivlen)
Herbert Xu6b7326c2006-07-30 15:41:01 +1000200 crypto_blkcipher_set_iv(tfm, esph->enc_data, esp->conf.ivlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800202 sg = &esp->sgbuf[0];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800204 if (unlikely(nfrags > ESP_NUM_FAST_SG)) {
205 sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC);
206 if (!sg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 }
Herbert Xu87bdc482007-10-10 15:45:25 -0700209 skb_to_sgvec(skb, sg, sizeof(*esph) + esp->conf.ivlen, elen);
Herbert Xu6b7326c2006-07-30 15:41:01 +1000210 err = crypto_blkcipher_decrypt(&desc, sg, sg, elen);
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800211 if (unlikely(sg != &esp->sgbuf[0]))
212 kfree(sg);
Herbert Xu6b7326c2006-07-30 15:41:01 +1000213 if (unlikely(err))
214 return err;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800215
216 if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2))
217 BUG();
218
219 padlen = nexthdr[0];
220 if (padlen+2 >= elen)
221 goto out;
222
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900223 /* ... check padding bits here. Silly. :-) */
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800224
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700225 iph = ip_hdr(skb);
Herbert Xu31a4ab92006-05-27 23:06:13 -0700226 ihl = iph->ihl * 4;
227
Herbert Xu752c1f42006-02-27 13:00:40 -0800228 if (x->encap) {
229 struct xfrm_encap_tmpl *encap = x->encap;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700230 struct udphdr *uh = (void *)(skb_network_header(skb) + ihl);
Herbert Xu752c1f42006-02-27 13:00:40 -0800231
232 /*
233 * 1) if the NAT-T peer's IP or port changed then
234 * advertize the change to the keying daemon.
235 * This is an inbound SA, so just compare
236 * SRC ports.
237 */
238 if (iph->saddr != x->props.saddr.a4 ||
239 uh->source != encap->encap_sport) {
240 xfrm_address_t ipaddr;
241
242 ipaddr.a4 = iph->saddr;
243 km_new_mapping(x, &ipaddr, uh->source);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900244
Herbert Xu752c1f42006-02-27 13:00:40 -0800245 /* XXX: perhaps add an extra
246 * policy check here, to see
247 * if we should allow or
248 * reject a packet from a
249 * different source
250 * address/port.
251 */
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800252 }
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900253
Herbert Xu752c1f42006-02-27 13:00:40 -0800254 /*
255 * 2) ignore UDP/TCP checksums in case
256 * of NAT-T in Transport Mode, or
257 * perform other post-processing fixes
258 * as per draft-ietf-ipsec-udp-encaps-06,
259 * section 3.1.2
260 */
Herbert Xu8bd17072007-10-10 15:41:41 -0700261 if (x->props.mode == XFRM_MODE_TRANSPORT)
Herbert Xu752c1f42006-02-27 13:00:40 -0800262 skb->ip_summed = CHECKSUM_UNNECESSARY;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800263 }
264
265 iph->protocol = nexthdr[1];
266 pskb_trim(skb, skb->len - alen - padlen - 2);
Arnaldo Carvalho de Melo967b05f2007-03-13 13:51:52 -0300267 __skb_pull(skb, sizeof(*esph) + esp->conf.ivlen);
268 skb_set_transport_header(skb, -ihl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269
270 return 0;
271
272out:
273 return -EINVAL;
274}
275
Patrick McHardyc5c25232007-04-09 11:47:18 -0700276static u32 esp4_get_mtu(struct xfrm_state *x, int mtu)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277{
278 struct esp_data *esp = x->data;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000279 u32 blksize = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4);
Patrick McHardyc5c25232007-04-09 11:47:18 -0700280 u32 align = max_t(u32, blksize, esp->conf.padlen);
281 u32 rem;
282
283 mtu -= x->props.header_len + esp->auth.icv_trunc_len;
284 rem = mtu & (align - 1);
285 mtu &= ~(align - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286
Diego Beltrami0a694522006-10-03 23:47:05 -0700287 switch (x->props.mode) {
288 case XFRM_MODE_TUNNEL:
Diego Beltrami0a694522006-10-03 23:47:05 -0700289 break;
290 default:
291 case XFRM_MODE_TRANSPORT:
292 /* The worst case */
Patrick McHardyc5c25232007-04-09 11:47:18 -0700293 mtu -= blksize - 4;
294 mtu += min_t(u32, blksize - 4, rem);
Diego Beltrami0a694522006-10-03 23:47:05 -0700295 break;
296 case XFRM_MODE_BEET:
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900297 /* The worst case. */
Patrick McHardyc5c25232007-04-09 11:47:18 -0700298 mtu += min_t(u32, IPV4_BEET_PHMAXLEN, rem);
Diego Beltrami0a694522006-10-03 23:47:05 -0700299 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300 }
Diego Beltrami0a694522006-10-03 23:47:05 -0700301
Patrick McHardyc5c25232007-04-09 11:47:18 -0700302 return mtu - 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303}
304
305static void esp4_err(struct sk_buff *skb, u32 info)
306{
307 struct iphdr *iph = (struct iphdr*)skb->data;
308 struct ip_esp_hdr *esph = (struct ip_esp_hdr*)(skb->data+(iph->ihl<<2));
309 struct xfrm_state *x;
310
Arnaldo Carvalho de Melo88c76642007-03-13 14:43:18 -0300311 if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH ||
312 icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 return;
314
315 x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, esph->spi, IPPROTO_ESP, AF_INET);
316 if (!x)
317 return;
Patrick McHardy64ce2072005-08-09 20:50:53 -0700318 NETDEBUG(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%08x\n",
319 ntohl(esph->spi), ntohl(iph->daddr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 xfrm_state_put(x);
321}
322
323static void esp_destroy(struct xfrm_state *x)
324{
325 struct esp_data *esp = x->data;
326
327 if (!esp)
328 return;
329
Herbert Xu6b7326c2006-07-30 15:41:01 +1000330 crypto_free_blkcipher(esp->conf.tfm);
Jesper Juhl573dbd92005-09-01 17:44:29 -0700331 esp->conf.tfm = NULL;
332 kfree(esp->conf.ivec);
333 esp->conf.ivec = NULL;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000334 crypto_free_hash(esp->auth.tfm);
Jesper Juhl573dbd92005-09-01 17:44:29 -0700335 esp->auth.tfm = NULL;
336 kfree(esp->auth.work_icv);
337 esp->auth.work_icv = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 kfree(esp);
339}
340
Herbert Xu72cb6962005-06-20 13:18:08 -0700341static int esp_init_state(struct xfrm_state *x)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342{
343 struct esp_data *esp = NULL;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000344 struct crypto_blkcipher *tfm;
Patrick McHardyc5c25232007-04-09 11:47:18 -0700345 u32 align;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 if (x->ealg == NULL)
348 goto error;
349
Panagiotis Issaris0da974f2006-07-21 14:51:30 -0700350 esp = kzalloc(sizeof(*esp), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 if (esp == NULL)
352 return -ENOMEM;
353
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 if (x->aalg) {
355 struct xfrm_algo_desc *aalg_desc;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000356 struct crypto_hash *hash;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357
Herbert Xu07d4ee52006-08-20 14:24:50 +1000358 hash = crypto_alloc_hash(x->aalg->alg_name, 0,
359 CRYPTO_ALG_ASYNC);
360 if (IS_ERR(hash))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 goto error;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000362
363 esp->auth.tfm = hash;
Herbert Xu4b7137f2007-10-08 17:13:44 -0700364 if (crypto_hash_setkey(hash, x->aalg->alg_key,
365 (x->aalg->alg_key_len + 7) / 8))
Herbert Xu07d4ee52006-08-20 14:24:50 +1000366 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367
368 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
369 BUG_ON(!aalg_desc);
370
371 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
Herbert Xu07d4ee52006-08-20 14:24:50 +1000372 crypto_hash_digestsize(hash)) {
Patrick McHardy64ce2072005-08-09 20:50:53 -0700373 NETDEBUG(KERN_INFO "ESP: %s digestsize %u != %hu\n",
374 x->aalg->alg_name,
Herbert Xu07d4ee52006-08-20 14:24:50 +1000375 crypto_hash_digestsize(hash),
Patrick McHardy64ce2072005-08-09 20:50:53 -0700376 aalg_desc->uinfo.auth.icv_fullbits/8);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 goto error;
378 }
379
380 esp->auth.icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
381 esp->auth.icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8;
382
383 esp->auth.work_icv = kmalloc(esp->auth.icv_full_len, GFP_KERNEL);
384 if (!esp->auth.work_icv)
385 goto error;
386 }
Herbert Xu4b7137f2007-10-08 17:13:44 -0700387
Herbert Xu6b7326c2006-07-30 15:41:01 +1000388 tfm = crypto_alloc_blkcipher(x->ealg->alg_name, 0, CRYPTO_ALG_ASYNC);
389 if (IS_ERR(tfm))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390 goto error;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000391 esp->conf.tfm = tfm;
392 esp->conf.ivlen = crypto_blkcipher_ivsize(tfm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 esp->conf.padlen = 0;
394 if (esp->conf.ivlen) {
395 esp->conf.ivec = kmalloc(esp->conf.ivlen, GFP_KERNEL);
396 if (unlikely(esp->conf.ivec == NULL))
397 goto error;
David S. Millere4bec822006-09-22 15:17:35 -0700398 esp->conf.ivinitted = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 }
Herbert Xu4b7137f2007-10-08 17:13:44 -0700400 if (crypto_blkcipher_setkey(tfm, x->ealg->alg_key,
401 (x->ealg->alg_key_len + 7) / 8))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402 goto error;
403 x->props.header_len = sizeof(struct ip_esp_hdr) + esp->conf.ivlen;
Masahide NAKAMURA7e49e6d2006-09-22 15:05:15 -0700404 if (x->props.mode == XFRM_MODE_TUNNEL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 x->props.header_len += sizeof(struct iphdr);
Patrick McHardyac758e32007-04-09 11:47:58 -0700406 else if (x->props.mode == XFRM_MODE_BEET)
407 x->props.header_len += IPV4_BEET_PHMAXLEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 if (x->encap) {
409 struct xfrm_encap_tmpl *encap = x->encap;
410
411 switch (encap->encap_type) {
412 default:
413 goto error;
414 case UDP_ENCAP_ESPINUDP:
415 x->props.header_len += sizeof(struct udphdr);
416 break;
417 case UDP_ENCAP_ESPINUDP_NON_IKE:
418 x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32);
419 break;
420 }
421 }
422 x->data = esp;
Patrick McHardyc5c25232007-04-09 11:47:18 -0700423 align = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4);
424 if (esp->conf.padlen)
425 align = max_t(u32, align, esp->conf.padlen);
426 x->props.trailer_len = align + 1 + esp->auth.icv_trunc_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427 return 0;
428
429error:
430 x->data = esp;
431 esp_destroy(x);
432 x->data = NULL;
433 return -EINVAL;
434}
435
436static struct xfrm_type esp_type =
437{
438 .description = "ESP4",
439 .owner = THIS_MODULE,
440 .proto = IPPROTO_ESP,
Herbert Xu436a0a42007-10-08 17:25:53 -0700441 .flags = XFRM_TYPE_REPLAY_PROT,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 .init_state = esp_init_state,
443 .destructor = esp_destroy,
Patrick McHardyc5c25232007-04-09 11:47:18 -0700444 .get_mtu = esp4_get_mtu,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 .input = esp_input,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 .output = esp_output
447};
448
449static struct net_protocol esp4_protocol = {
450 .handler = xfrm4_rcv,
451 .err_handler = esp4_err,
452 .no_policy = 1,
453};
454
455static int __init esp4_init(void)
456{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 if (xfrm_register_type(&esp_type, AF_INET) < 0) {
458 printk(KERN_INFO "ip esp init: can't add xfrm type\n");
459 return -EAGAIN;
460 }
461 if (inet_add_protocol(&esp4_protocol, IPPROTO_ESP) < 0) {
462 printk(KERN_INFO "ip esp init: can't add protocol\n");
463 xfrm_unregister_type(&esp_type, AF_INET);
464 return -EAGAIN;
465 }
466 return 0;
467}
468
469static void __exit esp4_fini(void)
470{
471 if (inet_del_protocol(&esp4_protocol, IPPROTO_ESP) < 0)
472 printk(KERN_INFO "ip esp close: can't remove protocol\n");
473 if (xfrm_unregister_type(&esp_type, AF_INET) < 0)
474 printk(KERN_INFO "ip esp close: can't remove xfrm type\n");
475}
476
477module_init(esp4_init);
478module_exit(esp4_fini);
479MODULE_LICENSE("GPL");
Masahide NAKAMURAd3d6dd32007-06-26 23:57:49 -0700480MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);