blob: c31bccb9b526c99d539c1c13a94531f23c982318 [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>
Adrian Bunk72998d82007-10-26 22:53:58 -07006#include <linux/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007#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;
Linus Torvalds1da177e2005-04-16 15:20:36 -070019 struct ip_esp_hdr *esph;
Herbert Xu6b7326c2006-07-30 15:41:01 +100020 struct crypto_blkcipher *tfm;
21 struct blkcipher_desc desc;
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 struct esp_data *esp;
23 struct sk_buff *trailer;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -070024 u8 *tail;
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 int blksize;
26 int clen;
27 int alen;
28 int nfrags;
29
Herbert Xu7b277b12007-10-10 15:44:06 -070030 /* skb is pure payload to encrypt */
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32 err = -ENOMEM;
33
34 /* Round to block size */
35 clen = skb->len;
36
37 esp = x->data;
38 alen = esp->auth.icv_trunc_len;
39 tfm = esp->conf.tfm;
Herbert Xu6b7326c2006-07-30 15:41:01 +100040 desc.tfm = tfm;
41 desc.flags = 0;
42 blksize = ALIGN(crypto_blkcipher_blocksize(tfm), 4);
Herbert Xua02a6422005-10-10 21:11:08 -070043 clen = ALIGN(clen + 2, blksize);
Linus Torvalds1da177e2005-04-16 15:20:36 -070044 if (esp->conf.padlen)
Herbert Xua02a6422005-10-10 21:11:08 -070045 clen = ALIGN(clen, esp->conf.padlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47 if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0)
48 goto error;
49
50 /* Fill padding... */
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -070051 tail = skb_tail_pointer(trailer);
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 do {
53 int i;
54 for (i=0; i<clen-skb->len - 2; i++)
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -070055 tail[i] = i + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 } while (0);
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -070057 tail[clen - skb->len - 2] = (clen - skb->len) - 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 pskb_put(skb, trailer, clen - skb->len);
59
Herbert Xu7b277b12007-10-10 15:44:06 -070060 skb_push(skb, -skb_network_offset(skb));
Herbert Xu87bdc482007-10-10 15:45:25 -070061 esph = ip_esp_hdr(skb);
Herbert Xu37fedd32007-10-10 15:44:44 -070062 *(skb_tail_pointer(trailer) - 1) = *skb_mac_header(skb);
63 *skb_mac_header(skb) = IPPROTO_ESP;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Herbert Xub7c65382007-10-09 13:33:35 -070065 spin_lock_bh(&x->lock);
66
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 /* this is non-NULL only with UDP Encapsulation */
68 if (x->encap) {
69 struct xfrm_encap_tmpl *encap = x->encap;
70 struct udphdr *uh;
Al Virod5a0a1e2006-11-08 00:23:14 -080071 __be32 *udpdata32;
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
73 uh = (struct udphdr *)esph;
74 uh->source = encap->encap_sport;
75 uh->dest = encap->encap_dport;
Herbert Xuceb1eec82007-10-10 15:45:52 -070076 uh->len = htons(skb->len + alen - skb_transport_offset(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 uh->check = 0;
78
79 switch (encap->encap_type) {
80 default:
81 case UDP_ENCAP_ESPINUDP:
82 esph = (struct ip_esp_hdr *)(uh + 1);
83 break;
84 case UDP_ENCAP_ESPINUDP_NON_IKE:
Al Virod5a0a1e2006-11-08 00:23:14 -080085 udpdata32 = (__be32 *)(uh + 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 udpdata32[0] = udpdata32[1] = 0;
87 esph = (struct ip_esp_hdr *)(udpdata32 + 2);
88 break;
89 }
90
Herbert Xu37fedd32007-10-10 15:44:44 -070091 *skb_mac_header(skb) = IPPROTO_UDP;
92 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070093
94 esph->spi = x->id.spi;
Herbert Xu436a0a42007-10-08 17:25:53 -070095 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
David S. Millere4bec822006-09-22 15:17:35 -070097 if (esp->conf.ivlen) {
98 if (unlikely(!esp->conf.ivinitted)) {
99 get_random_bytes(esp->conf.ivec, esp->conf.ivlen);
100 esp->conf.ivinitted = 1;
101 }
Herbert Xu6b7326c2006-07-30 15:41:01 +1000102 crypto_blkcipher_set_iv(tfm, esp->conf.ivec, esp->conf.ivlen);
David S. Millere4bec822006-09-22 15:17:35 -0700103 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104
105 do {
106 struct scatterlist *sg = &esp->sgbuf[0];
107
108 if (unlikely(nfrags > ESP_NUM_FAST_SG)) {
109 sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC);
110 if (!sg)
Herbert Xub7c65382007-10-09 13:33:35 -0700111 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 }
David S. Millered0e7e02007-10-26 00:38:39 -0700113 sg_init_table(sg, nfrags);
David S. Miller51c739d2007-10-30 21:29:29 -0700114 skb_to_sgvec(skb, sg,
115 esph->enc_data +
116 esp->conf.ivlen -
117 skb->data, clen);
Herbert Xu6b7326c2006-07-30 15:41:01 +1000118 err = crypto_blkcipher_encrypt(&desc, sg, sg, clen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 if (unlikely(sg != &esp->sgbuf[0]))
120 kfree(sg);
121 } while (0);
122
Herbert Xu6b7326c2006-07-30 15:41:01 +1000123 if (unlikely(err))
Herbert Xub7c65382007-10-09 13:33:35 -0700124 goto unlock;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000125
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 if (esp->conf.ivlen) {
Herbert Xu6b7326c2006-07-30 15:41:01 +1000127 memcpy(esph->enc_data, esp->conf.ivec, esp->conf.ivlen);
128 crypto_blkcipher_get_iv(tfm, esp->conf.ivec, esp->conf.ivlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 }
130
131 if (esp->auth.icv_full_len) {
Herbert Xu07d4ee52006-08-20 14:24:50 +1000132 err = esp_mac_digest(esp, skb, (u8 *)esph - skb->data,
133 sizeof(*esph) + esp->conf.ivlen + clen);
134 memcpy(pskb_put(skb, trailer, alen), esp->auth.work_icv, alen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 }
136
Herbert Xub7c65382007-10-09 13:33:35 -0700137unlock:
138 spin_unlock_bh(&x->lock);
139
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140error:
141 return err;
142}
143
144/*
145 * Note: detecting truncated vs. non-truncated authentication data is very
146 * expensive, so we only support truncated data, which is the recommended
147 * and common case.
148 */
Herbert Xue6956332006-04-01 00:52:46 -0800149static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150{
151 struct iphdr *iph;
152 struct ip_esp_hdr *esph;
153 struct esp_data *esp = x->data;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000154 struct crypto_blkcipher *tfm = esp->conf.tfm;
155 struct blkcipher_desc desc = { .tfm = tfm };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 struct sk_buff *trailer;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000157 int blksize = ALIGN(crypto_blkcipher_blocksize(tfm), 4);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 int alen = esp->auth.icv_trunc_len;
Herbert Xu87bdc482007-10-10 15:45:25 -0700159 int elen = skb->len - sizeof(*esph) - esp->conf.ivlen - alen;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 int nfrags;
Herbert Xu31a4ab92006-05-27 23:06:13 -0700161 int ihl;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800162 u8 nexthdr[2];
163 struct scatterlist *sg;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800164 int padlen;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000165 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166
Herbert Xu87bdc482007-10-10 15:45:25 -0700167 if (!pskb_may_pull(skb, sizeof(*esph)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 goto out;
169
170 if (elen <= 0 || (elen & (blksize-1)))
171 goto out;
172
173 /* If integrity check is required, do this. */
174 if (esp->auth.icv_full_len) {
Herbert Xu07d4ee52006-08-20 14:24:50 +1000175 u8 sum[alen];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176
Herbert Xu07d4ee52006-08-20 14:24:50 +1000177 err = esp_mac_digest(esp, skb, 0, skb->len - alen);
178 if (err)
179 goto out;
180
181 if (skb_copy_bits(skb, skb->len - alen, sum, alen))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 BUG();
183
Herbert Xu07d4ee52006-08-20 14:24:50 +1000184 if (unlikely(memcmp(esp->auth.work_icv, sum, alen))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 x->stats.integrity_failed++;
186 goto out;
187 }
188 }
189
190 if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0)
191 goto out;
192
193 skb->ip_summed = CHECKSUM_NONE;
194
Herbert Xu87bdc482007-10-10 15:45:25 -0700195 esph = (struct ip_esp_hdr *)skb->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196
197 /* Get ivec. This can be wrong, check against another impls. */
198 if (esp->conf.ivlen)
Herbert Xu6b7326c2006-07-30 15:41:01 +1000199 crypto_blkcipher_set_iv(tfm, esph->enc_data, esp->conf.ivlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800201 sg = &esp->sgbuf[0];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800203 if (unlikely(nfrags > ESP_NUM_FAST_SG)) {
204 sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC);
205 if (!sg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 }
David S. Millered0e7e02007-10-26 00:38:39 -0700208 sg_init_table(sg, nfrags);
David S. Miller51c739d2007-10-30 21:29:29 -0700209 skb_to_sgvec(skb, sg,
210 sizeof(*esph) + esp->conf.ivlen,
211 elen);
Herbert Xu6b7326c2006-07-30 15:41:01 +1000212 err = crypto_blkcipher_decrypt(&desc, sg, sg, elen);
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800213 if (unlikely(sg != &esp->sgbuf[0]))
214 kfree(sg);
Herbert Xu6b7326c2006-07-30 15:41:01 +1000215 if (unlikely(err))
216 return err;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800217
218 if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2))
219 BUG();
220
221 padlen = nexthdr[0];
222 if (padlen+2 >= elen)
223 goto out;
224
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900225 /* ... check padding bits here. Silly. :-) */
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800226
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700227 iph = ip_hdr(skb);
Herbert Xu31a4ab92006-05-27 23:06:13 -0700228 ihl = iph->ihl * 4;
229
Herbert Xu752c1f42006-02-27 13:00:40 -0800230 if (x->encap) {
231 struct xfrm_encap_tmpl *encap = x->encap;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700232 struct udphdr *uh = (void *)(skb_network_header(skb) + ihl);
Herbert Xu752c1f42006-02-27 13:00:40 -0800233
234 /*
235 * 1) if the NAT-T peer's IP or port changed then
236 * advertize the change to the keying daemon.
237 * This is an inbound SA, so just compare
238 * SRC ports.
239 */
240 if (iph->saddr != x->props.saddr.a4 ||
241 uh->source != encap->encap_sport) {
242 xfrm_address_t ipaddr;
243
244 ipaddr.a4 = iph->saddr;
245 km_new_mapping(x, &ipaddr, uh->source);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900246
Herbert Xu752c1f42006-02-27 13:00:40 -0800247 /* XXX: perhaps add an extra
248 * policy check here, to see
249 * if we should allow or
250 * reject a packet from a
251 * different source
252 * address/port.
253 */
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800254 }
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900255
Herbert Xu752c1f42006-02-27 13:00:40 -0800256 /*
257 * 2) ignore UDP/TCP checksums in case
258 * of NAT-T in Transport Mode, or
259 * perform other post-processing fixes
260 * as per draft-ietf-ipsec-udp-encaps-06,
261 * section 3.1.2
262 */
Herbert Xu8bd17072007-10-10 15:41:41 -0700263 if (x->props.mode == XFRM_MODE_TRANSPORT)
Herbert Xu752c1f42006-02-27 13:00:40 -0800264 skb->ip_summed = CHECKSUM_UNNECESSARY;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800265 }
266
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800267 pskb_trim(skb, skb->len - alen - padlen - 2);
Arnaldo Carvalho de Melo967b05f2007-03-13 13:51:52 -0300268 __skb_pull(skb, sizeof(*esph) + esp->conf.ivlen);
269 skb_set_transport_header(skb, -ihl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270
Herbert Xu631a66982007-10-10 15:46:21 -0700271 return nexthdr[1];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272
273out:
274 return -EINVAL;
275}
276
Patrick McHardyc5c25232007-04-09 11:47:18 -0700277static u32 esp4_get_mtu(struct xfrm_state *x, int mtu)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278{
279 struct esp_data *esp = x->data;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000280 u32 blksize = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4);
Patrick McHardyc5c25232007-04-09 11:47:18 -0700281 u32 align = max_t(u32, blksize, esp->conf.padlen);
282 u32 rem;
283
284 mtu -= x->props.header_len + esp->auth.icv_trunc_len;
285 rem = mtu & (align - 1);
286 mtu &= ~(align - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287
Diego Beltrami0a694522006-10-03 23:47:05 -0700288 switch (x->props.mode) {
289 case XFRM_MODE_TUNNEL:
Diego Beltrami0a694522006-10-03 23:47:05 -0700290 break;
291 default:
292 case XFRM_MODE_TRANSPORT:
293 /* The worst case */
Patrick McHardyc5c25232007-04-09 11:47:18 -0700294 mtu -= blksize - 4;
295 mtu += min_t(u32, blksize - 4, rem);
Diego Beltrami0a694522006-10-03 23:47:05 -0700296 break;
297 case XFRM_MODE_BEET:
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900298 /* The worst case. */
Patrick McHardyc5c25232007-04-09 11:47:18 -0700299 mtu += min_t(u32, IPV4_BEET_PHMAXLEN, rem);
Diego Beltrami0a694522006-10-03 23:47:05 -0700300 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 }
Diego Beltrami0a694522006-10-03 23:47:05 -0700302
Patrick McHardyc5c25232007-04-09 11:47:18 -0700303 return mtu - 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304}
305
306static void esp4_err(struct sk_buff *skb, u32 info)
307{
308 struct iphdr *iph = (struct iphdr*)skb->data;
309 struct ip_esp_hdr *esph = (struct ip_esp_hdr*)(skb->data+(iph->ihl<<2));
310 struct xfrm_state *x;
311
Arnaldo Carvalho de Melo88c76642007-03-13 14:43:18 -0300312 if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH ||
313 icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 return;
315
316 x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, esph->spi, IPPROTO_ESP, AF_INET);
317 if (!x)
318 return;
Patrick McHardy64ce2072005-08-09 20:50:53 -0700319 NETDEBUG(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%08x\n",
320 ntohl(esph->spi), ntohl(iph->daddr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 xfrm_state_put(x);
322}
323
324static void esp_destroy(struct xfrm_state *x)
325{
326 struct esp_data *esp = x->data;
327
328 if (!esp)
329 return;
330
Herbert Xu6b7326c2006-07-30 15:41:01 +1000331 crypto_free_blkcipher(esp->conf.tfm);
Jesper Juhl573dbd92005-09-01 17:44:29 -0700332 esp->conf.tfm = NULL;
333 kfree(esp->conf.ivec);
334 esp->conf.ivec = NULL;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000335 crypto_free_hash(esp->auth.tfm);
Jesper Juhl573dbd92005-09-01 17:44:29 -0700336 esp->auth.tfm = NULL;
337 kfree(esp->auth.work_icv);
338 esp->auth.work_icv = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 kfree(esp);
340}
341
Herbert Xu72cb6962005-06-20 13:18:08 -0700342static int esp_init_state(struct xfrm_state *x)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343{
344 struct esp_data *esp = NULL;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000345 struct crypto_blkcipher *tfm;
Patrick McHardyc5c25232007-04-09 11:47:18 -0700346 u32 align;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 if (x->ealg == NULL)
349 goto error;
350
Panagiotis Issaris0da974f2006-07-21 14:51:30 -0700351 esp = kzalloc(sizeof(*esp), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 if (esp == NULL)
353 return -ENOMEM;
354
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 if (x->aalg) {
356 struct xfrm_algo_desc *aalg_desc;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000357 struct crypto_hash *hash;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358
Herbert Xu07d4ee52006-08-20 14:24:50 +1000359 hash = crypto_alloc_hash(x->aalg->alg_name, 0,
360 CRYPTO_ALG_ASYNC);
361 if (IS_ERR(hash))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 goto error;
Herbert Xu07d4ee52006-08-20 14:24:50 +1000363
364 esp->auth.tfm = hash;
Herbert Xu4b7137f2007-10-08 17:13:44 -0700365 if (crypto_hash_setkey(hash, x->aalg->alg_key,
366 (x->aalg->alg_key_len + 7) / 8))
Herbert Xu07d4ee52006-08-20 14:24:50 +1000367 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368
369 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
370 BUG_ON(!aalg_desc);
371
372 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
Herbert Xu07d4ee52006-08-20 14:24:50 +1000373 crypto_hash_digestsize(hash)) {
Patrick McHardy64ce2072005-08-09 20:50:53 -0700374 NETDEBUG(KERN_INFO "ESP: %s digestsize %u != %hu\n",
375 x->aalg->alg_name,
Herbert Xu07d4ee52006-08-20 14:24:50 +1000376 crypto_hash_digestsize(hash),
Patrick McHardy64ce2072005-08-09 20:50:53 -0700377 aalg_desc->uinfo.auth.icv_fullbits/8);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 goto error;
379 }
380
381 esp->auth.icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
382 esp->auth.icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8;
383
384 esp->auth.work_icv = kmalloc(esp->auth.icv_full_len, GFP_KERNEL);
385 if (!esp->auth.work_icv)
386 goto error;
387 }
Herbert Xu4b7137f2007-10-08 17:13:44 -0700388
Herbert Xu6b7326c2006-07-30 15:41:01 +1000389 tfm = crypto_alloc_blkcipher(x->ealg->alg_name, 0, CRYPTO_ALG_ASYNC);
390 if (IS_ERR(tfm))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 goto error;
Herbert Xu6b7326c2006-07-30 15:41:01 +1000392 esp->conf.tfm = tfm;
393 esp->conf.ivlen = crypto_blkcipher_ivsize(tfm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 esp->conf.padlen = 0;
395 if (esp->conf.ivlen) {
396 esp->conf.ivec = kmalloc(esp->conf.ivlen, GFP_KERNEL);
397 if (unlikely(esp->conf.ivec == NULL))
398 goto error;
David S. Millere4bec822006-09-22 15:17:35 -0700399 esp->conf.ivinitted = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 }
Herbert Xu4b7137f2007-10-08 17:13:44 -0700401 if (crypto_blkcipher_setkey(tfm, x->ealg->alg_key,
402 (x->ealg->alg_key_len + 7) / 8))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 goto error;
404 x->props.header_len = sizeof(struct ip_esp_hdr) + esp->conf.ivlen;
Masahide NAKAMURA7e49e6d2006-09-22 15:05:15 -0700405 if (x->props.mode == XFRM_MODE_TUNNEL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 x->props.header_len += sizeof(struct iphdr);
Patrick McHardyac758e32007-04-09 11:47:58 -0700407 else if (x->props.mode == XFRM_MODE_BEET)
408 x->props.header_len += IPV4_BEET_PHMAXLEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 if (x->encap) {
410 struct xfrm_encap_tmpl *encap = x->encap;
411
412 switch (encap->encap_type) {
413 default:
414 goto error;
415 case UDP_ENCAP_ESPINUDP:
416 x->props.header_len += sizeof(struct udphdr);
417 break;
418 case UDP_ENCAP_ESPINUDP_NON_IKE:
419 x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32);
420 break;
421 }
422 }
423 x->data = esp;
Patrick McHardyc5c25232007-04-09 11:47:18 -0700424 align = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4);
425 if (esp->conf.padlen)
426 align = max_t(u32, align, esp->conf.padlen);
427 x->props.trailer_len = align + 1 + esp->auth.icv_trunc_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428 return 0;
429
430error:
431 x->data = esp;
432 esp_destroy(x);
433 x->data = NULL;
434 return -EINVAL;
435}
436
437static struct xfrm_type esp_type =
438{
439 .description = "ESP4",
440 .owner = THIS_MODULE,
441 .proto = IPPROTO_ESP,
Herbert Xu436a0a42007-10-08 17:25:53 -0700442 .flags = XFRM_TYPE_REPLAY_PROT,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 .init_state = esp_init_state,
444 .destructor = esp_destroy,
Patrick McHardyc5c25232007-04-09 11:47:18 -0700445 .get_mtu = esp4_get_mtu,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 .input = esp_input,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 .output = esp_output
448};
449
450static struct net_protocol esp4_protocol = {
451 .handler = xfrm4_rcv,
452 .err_handler = esp4_err,
453 .no_policy = 1,
454};
455
456static int __init esp4_init(void)
457{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 if (xfrm_register_type(&esp_type, AF_INET) < 0) {
459 printk(KERN_INFO "ip esp init: can't add xfrm type\n");
460 return -EAGAIN;
461 }
462 if (inet_add_protocol(&esp4_protocol, IPPROTO_ESP) < 0) {
463 printk(KERN_INFO "ip esp init: can't add protocol\n");
464 xfrm_unregister_type(&esp_type, AF_INET);
465 return -EAGAIN;
466 }
467 return 0;
468}
469
470static void __exit esp4_fini(void)
471{
472 if (inet_del_protocol(&esp4_protocol, IPPROTO_ESP) < 0)
473 printk(KERN_INFO "ip esp close: can't remove protocol\n");
474 if (xfrm_unregister_type(&esp_type, AF_INET) < 0)
475 printk(KERN_INFO "ip esp close: can't remove xfrm type\n");
476}
477
478module_init(esp4_init);
479module_exit(esp4_fini);
480MODULE_LICENSE("GPL");
Masahide NAKAMURAd3d6dd32007-06-26 23:57:49 -0700481MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);