Commit | Line | Data |
---|---|---|
afd46503 JP |
1 | #define pr_fmt(fmt) "IPsec: " fmt |
2 | ||
38320c70 HX |
3 | #include <crypto/aead.h> |
4 | #include <crypto/authenc.h> | |
6b7326c8 | 5 | #include <linux/err.h> |
1da177e4 LT |
6 | #include <linux/module.h> |
7 | #include <net/ip.h> | |
8 | #include <net/xfrm.h> | |
9 | #include <net/esp.h> | |
72998d8c | 10 | #include <linux/scatterlist.h> |
a02a6422 | 11 | #include <linux/kernel.h> |
1da177e4 | 12 | #include <linux/pfkeyv2.h> |
38320c70 HX |
13 | #include <linux/rtnetlink.h> |
14 | #include <linux/slab.h> | |
b7c6538c | 15 | #include <linux/spinlock.h> |
2017a72c | 16 | #include <linux/in6.h> |
1da177e4 | 17 | #include <net/icmp.h> |
14c85021 | 18 | #include <net/protocol.h> |
1da177e4 LT |
19 | #include <net/udp.h> |
20 | ||
38320c70 HX |
21 | struct esp_skb_cb { |
22 | struct xfrm_skb_cb xfrm; | |
23 | void *tmp; | |
24 | }; | |
25 | ||
26 | #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) | |
27 | ||
d979e20f MW |
28 | static u32 esp4_get_mtu(struct xfrm_state *x, int mtu); |
29 | ||
38320c70 HX |
30 | /* |
31 | * Allocate an AEAD request structure with extra space for SG and IV. | |
32 | * | |
33 | * For alignment considerations the IV is placed at the front, followed | |
34 | * by the request and finally the SG list. | |
35 | * | |
36 | * TODO: Use spare space in skb for this where possible. | |
37 | */ | |
0dc49e9b | 38 | static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqhilen) |
38320c70 HX |
39 | { |
40 | unsigned int len; | |
41 | ||
0dc49e9b SK |
42 | len = seqhilen; |
43 | ||
44 | len += crypto_aead_ivsize(aead); | |
45 | ||
38320c70 HX |
46 | if (len) { |
47 | len += crypto_aead_alignmask(aead) & | |
48 | ~(crypto_tfm_ctx_alignment() - 1); | |
49 | len = ALIGN(len, crypto_tfm_ctx_alignment()); | |
50 | } | |
51 | ||
52 | len += sizeof(struct aead_givcrypt_request) + crypto_aead_reqsize(aead); | |
53 | len = ALIGN(len, __alignof__(struct scatterlist)); | |
54 | ||
55 | len += sizeof(struct scatterlist) * nfrags; | |
56 | ||
57 | return kmalloc(len, GFP_ATOMIC); | |
58 | } | |
59 | ||
0dc49e9b SK |
60 | static inline __be32 *esp_tmp_seqhi(void *tmp) |
61 | { | |
62 | return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); | |
63 | } | |
64 | static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) | |
38320c70 HX |
65 | { |
66 | return crypto_aead_ivsize(aead) ? | |
0dc49e9b SK |
67 | PTR_ALIGN((u8 *)tmp + seqhilen, |
68 | crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; | |
38320c70 HX |
69 | } |
70 | ||
71 | static inline struct aead_givcrypt_request *esp_tmp_givreq( | |
72 | struct crypto_aead *aead, u8 *iv) | |
73 | { | |
74 | struct aead_givcrypt_request *req; | |
75 | ||
76 | req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), | |
77 | crypto_tfm_ctx_alignment()); | |
78 | aead_givcrypt_set_tfm(req, aead); | |
79 | return req; | |
80 | } | |
81 | ||
82 | static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) | |
83 | { | |
84 | struct aead_request *req; | |
85 | ||
86 | req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), | |
87 | crypto_tfm_ctx_alignment()); | |
88 | aead_request_set_tfm(req, aead); | |
89 | return req; | |
90 | } | |
91 | ||
92 | static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, | |
93 | struct aead_request *req) | |
94 | { | |
95 | return (void *)ALIGN((unsigned long)(req + 1) + | |
96 | crypto_aead_reqsize(aead), | |
97 | __alignof__(struct scatterlist)); | |
98 | } | |
99 | ||
100 | static inline struct scatterlist *esp_givreq_sg( | |
101 | struct crypto_aead *aead, struct aead_givcrypt_request *req) | |
102 | { | |
103 | return (void *)ALIGN((unsigned long)(req + 1) + | |
104 | crypto_aead_reqsize(aead), | |
105 | __alignof__(struct scatterlist)); | |
106 | } | |
107 | ||
108 | static void esp_output_done(struct crypto_async_request *base, int err) | |
109 | { | |
110 | struct sk_buff *skb = base->data; | |
111 | ||
112 | kfree(ESP_SKB_CB(skb)->tmp); | |
113 | xfrm_output_resume(skb, err); | |
114 | } | |
115 | ||
1da177e4 LT |
116 | static int esp_output(struct xfrm_state *x, struct sk_buff *skb) |
117 | { | |
118 | int err; | |
1da177e4 | 119 | struct ip_esp_hdr *esph; |
38320c70 HX |
120 | struct crypto_aead *aead; |
121 | struct aead_givcrypt_request *req; | |
122 | struct scatterlist *sg; | |
123 | struct scatterlist *asg; | |
1da177e4 | 124 | struct sk_buff *trailer; |
38320c70 HX |
125 | void *tmp; |
126 | u8 *iv; | |
27a884dc | 127 | u8 *tail; |
1da177e4 LT |
128 | int blksize; |
129 | int clen; | |
130 | int alen; | |
d979e20f MW |
131 | int plen; |
132 | int tfclen; | |
1da177e4 | 133 | int nfrags; |
0dc49e9b SK |
134 | int assoclen; |
135 | int sglists; | |
136 | int seqhilen; | |
137 | __be32 *seqhi; | |
1da177e4 | 138 | |
7b277b1a | 139 | /* skb is pure payload to encrypt */ |
1da177e4 | 140 | |
1c5ad13f | 141 | aead = x->data; |
38320c70 HX |
142 | alen = crypto_aead_authsize(aead); |
143 | ||
d979e20f MW |
144 | tfclen = 0; |
145 | if (x->tfcpad) { | |
146 | struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); | |
147 | u32 padto; | |
148 | ||
149 | padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached)); | |
150 | if (skb->len < padto) | |
151 | tfclen = padto - skb->len; | |
152 | } | |
38320c70 | 153 | blksize = ALIGN(crypto_aead_blocksize(aead), 4); |
d979e20f | 154 | clen = ALIGN(skb->len + 2 + tfclen, blksize); |
d979e20f | 155 | plen = clen - skb->len - tfclen; |
38320c70 | 156 | |
d979e20f MW |
157 | err = skb_cow_data(skb, tfclen + plen + alen, &trailer); |
158 | if (err < 0) | |
38320c70 HX |
159 | goto error; |
160 | nfrags = err; | |
1da177e4 | 161 | |
0dc49e9b SK |
162 | assoclen = sizeof(*esph); |
163 | sglists = 1; | |
164 | seqhilen = 0; | |
165 | ||
166 | if (x->props.flags & XFRM_STATE_ESN) { | |
167 | sglists += 2; | |
168 | seqhilen += sizeof(__be32); | |
169 | assoclen += seqhilen; | |
170 | } | |
171 | ||
172 | tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); | |
06848c10 WY |
173 | if (!tmp) { |
174 | err = -ENOMEM; | |
1da177e4 | 175 | goto error; |
06848c10 | 176 | } |
1da177e4 | 177 | |
0dc49e9b SK |
178 | seqhi = esp_tmp_seqhi(tmp); |
179 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 HX |
180 | req = esp_tmp_givreq(aead, iv); |
181 | asg = esp_givreq_sg(aead, req); | |
0dc49e9b | 182 | sg = asg + sglists; |
38320c70 | 183 | |
1da177e4 | 184 | /* Fill padding... */ |
27a884dc | 185 | tail = skb_tail_pointer(trailer); |
d979e20f MW |
186 | if (tfclen) { |
187 | memset(tail, 0, tfclen); | |
188 | tail += tfclen; | |
189 | } | |
1da177e4 LT |
190 | do { |
191 | int i; | |
d979e20f | 192 | for (i = 0; i < plen - 2; i++) |
27a884dc | 193 | tail[i] = i + 1; |
1da177e4 | 194 | } while (0); |
d979e20f MW |
195 | tail[plen - 2] = plen - 2; |
196 | tail[plen - 1] = *skb_mac_header(skb); | |
38320c70 | 197 | pskb_put(skb, trailer, clen - skb->len + alen); |
1da177e4 | 198 | |
7b277b1a | 199 | skb_push(skb, -skb_network_offset(skb)); |
87bdc48d | 200 | esph = ip_esp_hdr(skb); |
37fedd3a | 201 | *skb_mac_header(skb) = IPPROTO_ESP; |
1da177e4 LT |
202 | |
203 | /* this is non-NULL only with UDP Encapsulation */ | |
204 | if (x->encap) { | |
205 | struct xfrm_encap_tmpl *encap = x->encap; | |
206 | struct udphdr *uh; | |
d5a0a1e3 | 207 | __be32 *udpdata32; |
5e226e4d | 208 | __be16 sport, dport; |
38320c70 HX |
209 | int encap_type; |
210 | ||
211 | spin_lock_bh(&x->lock); | |
212 | sport = encap->encap_sport; | |
213 | dport = encap->encap_dport; | |
214 | encap_type = encap->encap_type; | |
215 | spin_unlock_bh(&x->lock); | |
1da177e4 LT |
216 | |
217 | uh = (struct udphdr *)esph; | |
38320c70 HX |
218 | uh->source = sport; |
219 | uh->dest = dport; | |
220 | uh->len = htons(skb->len - skb_transport_offset(skb)); | |
1da177e4 LT |
221 | uh->check = 0; |
222 | ||
38320c70 | 223 | switch (encap_type) { |
1da177e4 LT |
224 | default: |
225 | case UDP_ENCAP_ESPINUDP: | |
226 | esph = (struct ip_esp_hdr *)(uh + 1); | |
227 | break; | |
228 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
d5a0a1e3 | 229 | udpdata32 = (__be32 *)(uh + 1); |
1da177e4 LT |
230 | udpdata32[0] = udpdata32[1] = 0; |
231 | esph = (struct ip_esp_hdr *)(udpdata32 + 2); | |
232 | break; | |
233 | } | |
234 | ||
37fedd3a HX |
235 | *skb_mac_header(skb) = IPPROTO_UDP; |
236 | } | |
1da177e4 LT |
237 | |
238 | esph->spi = x->id.spi; | |
1ce3644a | 239 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); |
1da177e4 | 240 | |
38320c70 HX |
241 | sg_init_table(sg, nfrags); |
242 | skb_to_sgvec(skb, sg, | |
243 | esph->enc_data + crypto_aead_ivsize(aead) - skb->data, | |
244 | clen + alen); | |
0dc49e9b SK |
245 | |
246 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
247 | sg_init_table(asg, 3); | |
248 | sg_set_buf(asg, &esph->spi, sizeof(__be32)); | |
249 | *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); | |
250 | sg_set_buf(asg + 1, seqhi, seqhilen); | |
251 | sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); | |
252 | } else | |
253 | sg_init_one(asg, esph, sizeof(*esph)); | |
38320c70 HX |
254 | |
255 | aead_givcrypt_set_callback(req, 0, esp_output_done, skb); | |
256 | aead_givcrypt_set_crypt(req, sg, sg, clen, iv); | |
0dc49e9b | 257 | aead_givcrypt_set_assoc(req, asg, assoclen); |
b318e0e4 | 258 | aead_givcrypt_set_giv(req, esph->enc_data, |
1ce3644a | 259 | XFRM_SKB_CB(skb)->seq.output.low); |
38320c70 HX |
260 | |
261 | ESP_SKB_CB(skb)->tmp = tmp; | |
262 | err = crypto_aead_givencrypt(req); | |
263 | if (err == -EINPROGRESS) | |
264 | goto error; | |
1da177e4 | 265 | |
38320c70 HX |
266 | if (err == -EBUSY) |
267 | err = NET_XMIT_DROP; | |
1da177e4 | 268 | |
38320c70 | 269 | kfree(tmp); |
b7c6538c | 270 | |
1da177e4 LT |
271 | error: |
272 | return err; | |
273 | } | |
274 | ||
38320c70 | 275 | static int esp_input_done2(struct sk_buff *skb, int err) |
1da177e4 | 276 | { |
b71d1d42 | 277 | const struct iphdr *iph; |
38320c70 | 278 | struct xfrm_state *x = xfrm_input_state(skb); |
1c5ad13f | 279 | struct crypto_aead *aead = x->data; |
38320c70 HX |
280 | int alen = crypto_aead_authsize(aead); |
281 | int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
282 | int elen = skb->len - hlen; | |
31a4ab93 | 283 | int ihl; |
4bf05ece | 284 | u8 nexthdr[2]; |
4bf05ece | 285 | int padlen; |
1da177e4 | 286 | |
38320c70 | 287 | kfree(ESP_SKB_CB(skb)->tmp); |
0ebea8ef | 288 | |
6b7326c8 | 289 | if (unlikely(err)) |
668dc8af | 290 | goto out; |
1da177e4 | 291 | |
4bf05ece HX |
292 | if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) |
293 | BUG(); | |
1da177e4 | 294 | |
668dc8af | 295 | err = -EINVAL; |
4bf05ece | 296 | padlen = nexthdr[0]; |
38320c70 | 297 | if (padlen + 2 + alen >= elen) |
4bf05ece | 298 | goto out; |
1da177e4 | 299 | |
e905a9ed | 300 | /* ... check padding bits here. Silly. :-) */ |
1da177e4 | 301 | |
eddc9ec5 | 302 | iph = ip_hdr(skb); |
31a4ab93 HX |
303 | ihl = iph->ihl * 4; |
304 | ||
752c1f4c HX |
305 | if (x->encap) { |
306 | struct xfrm_encap_tmpl *encap = x->encap; | |
d56f90a7 | 307 | struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); |
752c1f4c HX |
308 | |
309 | /* | |
310 | * 1) if the NAT-T peer's IP or port changed then | |
311 | * advertize the change to the keying daemon. | |
312 | * This is an inbound SA, so just compare | |
313 | * SRC ports. | |
314 | */ | |
315 | if (iph->saddr != x->props.saddr.a4 || | |
316 | uh->source != encap->encap_sport) { | |
317 | xfrm_address_t ipaddr; | |
318 | ||
319 | ipaddr.a4 = iph->saddr; | |
320 | km_new_mapping(x, &ipaddr, uh->source); | |
e905a9ed | 321 | |
752c1f4c HX |
322 | /* XXX: perhaps add an extra |
323 | * policy check here, to see | |
324 | * if we should allow or | |
325 | * reject a packet from a | |
326 | * different source | |
327 | * address/port. | |
328 | */ | |
1da177e4 | 329 | } |
e905a9ed | 330 | |
752c1f4c HX |
331 | /* |
332 | * 2) ignore UDP/TCP checksums in case | |
333 | * of NAT-T in Transport Mode, or | |
334 | * perform other post-processing fixes | |
335 | * as per draft-ietf-ipsec-udp-encaps-06, | |
336 | * section 3.1.2 | |
337 | */ | |
8bd17075 | 338 | if (x->props.mode == XFRM_MODE_TRANSPORT) |
752c1f4c | 339 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
1da177e4 LT |
340 | } |
341 | ||
4bf05ece | 342 | pskb_trim(skb, skb->len - alen - padlen - 2); |
38320c70 | 343 | __skb_pull(skb, hlen); |
7143dfac LR |
344 | if (x->props.mode == XFRM_MODE_TUNNEL) |
345 | skb_reset_transport_header(skb); | |
346 | else | |
347 | skb_set_transport_header(skb, -ihl); | |
4bf05ece | 348 | |
38320c70 HX |
349 | err = nexthdr[1]; |
350 | ||
351 | /* RFC4303: Drop dummy packets without any error */ | |
352 | if (err == IPPROTO_NONE) | |
353 | err = -EINVAL; | |
354 | ||
355 | out: | |
356 | return err; | |
357 | } | |
358 | ||
359 | static void esp_input_done(struct crypto_async_request *base, int err) | |
360 | { | |
361 | struct sk_buff *skb = base->data; | |
362 | ||
363 | xfrm_input_resume(skb, esp_input_done2(skb, err)); | |
364 | } | |
365 | ||
366 | /* | |
367 | * Note: detecting truncated vs. non-truncated authentication data is very | |
368 | * expensive, so we only support truncated data, which is the recommended | |
369 | * and common case. | |
370 | */ | |
371 | static int esp_input(struct xfrm_state *x, struct sk_buff *skb) | |
372 | { | |
373 | struct ip_esp_hdr *esph; | |
1c5ad13f | 374 | struct crypto_aead *aead = x->data; |
38320c70 HX |
375 | struct aead_request *req; |
376 | struct sk_buff *trailer; | |
377 | int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead); | |
378 | int nfrags; | |
0dc49e9b SK |
379 | int assoclen; |
380 | int sglists; | |
381 | int seqhilen; | |
382 | __be32 *seqhi; | |
38320c70 HX |
383 | void *tmp; |
384 | u8 *iv; | |
385 | struct scatterlist *sg; | |
386 | struct scatterlist *asg; | |
387 | int err = -EINVAL; | |
388 | ||
920fc941 | 389 | if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) |
38320c70 HX |
390 | goto out; |
391 | ||
392 | if (elen <= 0) | |
393 | goto out; | |
394 | ||
395 | if ((err = skb_cow_data(skb, 0, &trailer)) < 0) | |
396 | goto out; | |
397 | nfrags = err; | |
398 | ||
0dc49e9b SK |
399 | assoclen = sizeof(*esph); |
400 | sglists = 1; | |
401 | seqhilen = 0; | |
402 | ||
403 | if (x->props.flags & XFRM_STATE_ESN) { | |
404 | sglists += 2; | |
405 | seqhilen += sizeof(__be32); | |
406 | assoclen += seqhilen; | |
407 | } | |
408 | ||
38320c70 | 409 | err = -ENOMEM; |
0dc49e9b | 410 | tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); |
38320c70 HX |
411 | if (!tmp) |
412 | goto out; | |
413 | ||
414 | ESP_SKB_CB(skb)->tmp = tmp; | |
0dc49e9b SK |
415 | seqhi = esp_tmp_seqhi(tmp); |
416 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 HX |
417 | req = esp_tmp_req(aead, iv); |
418 | asg = esp_req_sg(aead, req); | |
0dc49e9b | 419 | sg = asg + sglists; |
38320c70 HX |
420 | |
421 | skb->ip_summed = CHECKSUM_NONE; | |
422 | ||
423 | esph = (struct ip_esp_hdr *)skb->data; | |
424 | ||
425 | /* Get ivec. This can be wrong, check against another impls. */ | |
426 | iv = esph->enc_data; | |
427 | ||
428 | sg_init_table(sg, nfrags); | |
429 | skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen); | |
0dc49e9b SK |
430 | |
431 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
432 | sg_init_table(asg, 3); | |
433 | sg_set_buf(asg, &esph->spi, sizeof(__be32)); | |
434 | *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; | |
435 | sg_set_buf(asg + 1, seqhi, seqhilen); | |
436 | sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); | |
437 | } else | |
438 | sg_init_one(asg, esph, sizeof(*esph)); | |
38320c70 HX |
439 | |
440 | aead_request_set_callback(req, 0, esp_input_done, skb); | |
441 | aead_request_set_crypt(req, sg, sg, elen, iv); | |
0dc49e9b | 442 | aead_request_set_assoc(req, asg, assoclen); |
38320c70 HX |
443 | |
444 | err = crypto_aead_decrypt(req); | |
445 | if (err == -EINPROGRESS) | |
446 | goto out; | |
447 | ||
448 | err = esp_input_done2(skb, err); | |
1da177e4 LT |
449 | |
450 | out: | |
668dc8af | 451 | return err; |
1da177e4 LT |
452 | } |
453 | ||
c5c25238 | 454 | static u32 esp4_get_mtu(struct xfrm_state *x, int mtu) |
1da177e4 | 455 | { |
1c5ad13f MK |
456 | struct crypto_aead *aead = x->data; |
457 | u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); | |
91657eaf | 458 | unsigned int net_adj; |
0a69452c DB |
459 | |
460 | switch (x->props.mode) { | |
0a69452c | 461 | case XFRM_MODE_TRANSPORT: |
0a69452c | 462 | case XFRM_MODE_BEET: |
91657eaf | 463 | net_adj = sizeof(struct iphdr); |
0a69452c | 464 | break; |
91657eaf BP |
465 | case XFRM_MODE_TUNNEL: |
466 | net_adj = 0; | |
467 | break; | |
468 | default: | |
469 | BUG(); | |
1da177e4 | 470 | } |
0a69452c | 471 | |
1c5ad13f | 472 | return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - |
123b0d1b | 473 | net_adj) & ~(blksize - 1)) + net_adj - 2; |
1da177e4 LT |
474 | } |
475 | ||
476 | static void esp4_err(struct sk_buff *skb, u32 info) | |
477 | { | |
4fb236ba | 478 | struct net *net = dev_net(skb->dev); |
b71d1d42 | 479 | const struct iphdr *iph = (const struct iphdr *)skb->data; |
d9319100 | 480 | struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); |
1da177e4 LT |
481 | struct xfrm_state *x; |
482 | ||
55be7a9c DM |
483 | switch (icmp_hdr(skb)->type) { |
484 | case ICMP_DEST_UNREACH: | |
485 | if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) | |
486 | return; | |
487 | case ICMP_REDIRECT: | |
488 | break; | |
489 | default: | |
1da177e4 | 490 | return; |
55be7a9c | 491 | } |
1da177e4 | 492 | |
b71d1d42 ED |
493 | x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, |
494 | esph->spi, IPPROTO_ESP, AF_INET); | |
1da177e4 LT |
495 | if (!x) |
496 | return; | |
55be7a9c | 497 | |
387aa65a | 498 | if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) |
55be7a9c | 499 | ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0); |
387aa65a | 500 | else |
55be7a9c | 501 | ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0); |
1da177e4 LT |
502 | xfrm_state_put(x); |
503 | } | |
504 | ||
505 | static void esp_destroy(struct xfrm_state *x) | |
506 | { | |
1c5ad13f | 507 | struct crypto_aead *aead = x->data; |
1da177e4 | 508 | |
1c5ad13f | 509 | if (!aead) |
1da177e4 LT |
510 | return; |
511 | ||
1c5ad13f | 512 | crypto_free_aead(aead); |
1da177e4 LT |
513 | } |
514 | ||
1a6509d9 | 515 | static int esp_init_aead(struct xfrm_state *x) |
1da177e4 | 516 | { |
1a6509d9 HX |
517 | struct crypto_aead *aead; |
518 | int err; | |
519 | ||
520 | aead = crypto_alloc_aead(x->aead->alg_name, 0, 0); | |
521 | err = PTR_ERR(aead); | |
522 | if (IS_ERR(aead)) | |
523 | goto error; | |
524 | ||
1c5ad13f | 525 | x->data = aead; |
1a6509d9 HX |
526 | |
527 | err = crypto_aead_setkey(aead, x->aead->alg_key, | |
528 | (x->aead->alg_key_len + 7) / 8); | |
529 | if (err) | |
530 | goto error; | |
531 | ||
532 | err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); | |
533 | if (err) | |
534 | goto error; | |
535 | ||
536 | error: | |
537 | return err; | |
538 | } | |
539 | ||
540 | static int esp_init_authenc(struct xfrm_state *x) | |
541 | { | |
38320c70 HX |
542 | struct crypto_aead *aead; |
543 | struct crypto_authenc_key_param *param; | |
544 | struct rtattr *rta; | |
545 | char *key; | |
546 | char *p; | |
547 | char authenc_name[CRYPTO_MAX_ALG_NAME]; | |
38320c70 HX |
548 | unsigned int keylen; |
549 | int err; | |
1da177e4 | 550 | |
1a6509d9 | 551 | err = -EINVAL; |
1da177e4 | 552 | if (x->ealg == NULL) |
1a6509d9 | 553 | goto error; |
38320c70 | 554 | |
1a6509d9 | 555 | err = -ENAMETOOLONG; |
0dc49e9b SK |
556 | |
557 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
558 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
559 | "authencesn(%s,%s)", | |
560 | x->aalg ? x->aalg->alg_name : "digest_null", | |
561 | x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
562 | goto error; | |
563 | } else { | |
564 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
565 | "authenc(%s,%s)", | |
566 | x->aalg ? x->aalg->alg_name : "digest_null", | |
567 | x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
568 | goto error; | |
569 | } | |
38320c70 HX |
570 | |
571 | aead = crypto_alloc_aead(authenc_name, 0, 0); | |
572 | err = PTR_ERR(aead); | |
573 | if (IS_ERR(aead)) | |
574 | goto error; | |
575 | ||
1c5ad13f | 576 | x->data = aead; |
38320c70 HX |
577 | |
578 | keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + | |
579 | (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); | |
580 | err = -ENOMEM; | |
581 | key = kmalloc(keylen, GFP_KERNEL); | |
582 | if (!key) | |
583 | goto error; | |
584 | ||
585 | p = key; | |
586 | rta = (void *)p; | |
587 | rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; | |
588 | rta->rta_len = RTA_LENGTH(sizeof(*param)); | |
589 | param = RTA_DATA(rta); | |
590 | p += RTA_SPACE(sizeof(*param)); | |
591 | ||
1da177e4 LT |
592 | if (x->aalg) { |
593 | struct xfrm_algo_desc *aalg_desc; | |
594 | ||
38320c70 HX |
595 | memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); |
596 | p += (x->aalg->alg_key_len + 7) / 8; | |
1da177e4 LT |
597 | |
598 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); | |
599 | BUG_ON(!aalg_desc); | |
600 | ||
38320c70 | 601 | err = -EINVAL; |
1da177e4 | 602 | if (aalg_desc->uinfo.auth.icv_fullbits/8 != |
38320c70 | 603 | crypto_aead_authsize(aead)) { |
64ce2073 PM |
604 | NETDEBUG(KERN_INFO "ESP: %s digestsize %u != %hu\n", |
605 | x->aalg->alg_name, | |
38320c70 | 606 | crypto_aead_authsize(aead), |
64ce2073 | 607 | aalg_desc->uinfo.auth.icv_fullbits/8); |
38320c70 | 608 | goto free_key; |
1da177e4 LT |
609 | } |
610 | ||
38320c70 | 611 | err = crypto_aead_setauthsize( |
8f8a088c | 612 | aead, x->aalg->alg_trunc_len / 8); |
38320c70 HX |
613 | if (err) |
614 | goto free_key; | |
1da177e4 | 615 | } |
4b7137ff | 616 | |
38320c70 HX |
617 | param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); |
618 | memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); | |
619 | ||
620 | err = crypto_aead_setkey(aead, key, keylen); | |
621 | ||
622 | free_key: | |
623 | kfree(key); | |
624 | ||
1a6509d9 HX |
625 | error: |
626 | return err; | |
627 | } | |
628 | ||
629 | static int esp_init_state(struct xfrm_state *x) | |
630 | { | |
1a6509d9 HX |
631 | struct crypto_aead *aead; |
632 | u32 align; | |
633 | int err; | |
634 | ||
1c5ad13f | 635 | x->data = NULL; |
1a6509d9 HX |
636 | |
637 | if (x->aead) | |
638 | err = esp_init_aead(x); | |
639 | else | |
640 | err = esp_init_authenc(x); | |
641 | ||
38320c70 | 642 | if (err) |
1da177e4 | 643 | goto error; |
38320c70 | 644 | |
1c5ad13f | 645 | aead = x->data; |
1a6509d9 | 646 | |
38320c70 HX |
647 | x->props.header_len = sizeof(struct ip_esp_hdr) + |
648 | crypto_aead_ivsize(aead); | |
7e49e6de | 649 | if (x->props.mode == XFRM_MODE_TUNNEL) |
1da177e4 | 650 | x->props.header_len += sizeof(struct iphdr); |
eb49e630 | 651 | else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6) |
ac758e3c | 652 | x->props.header_len += IPV4_BEET_PHMAXLEN; |
1da177e4 LT |
653 | if (x->encap) { |
654 | struct xfrm_encap_tmpl *encap = x->encap; | |
655 | ||
656 | switch (encap->encap_type) { | |
657 | default: | |
658 | goto error; | |
659 | case UDP_ENCAP_ESPINUDP: | |
660 | x->props.header_len += sizeof(struct udphdr); | |
661 | break; | |
662 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
663 | x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32); | |
664 | break; | |
665 | } | |
666 | } | |
38320c70 HX |
667 | |
668 | align = ALIGN(crypto_aead_blocksize(aead), 4); | |
1c5ad13f | 669 | x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); |
1da177e4 LT |
670 | |
671 | error: | |
38320c70 | 672 | return err; |
1da177e4 LT |
673 | } |
674 | ||
533cb5b0 | 675 | static const struct xfrm_type esp_type = |
1da177e4 LT |
676 | { |
677 | .description = "ESP4", | |
678 | .owner = THIS_MODULE, | |
679 | .proto = IPPROTO_ESP, | |
436a0a40 | 680 | .flags = XFRM_TYPE_REPLAY_PROT, |
1da177e4 LT |
681 | .init_state = esp_init_state, |
682 | .destructor = esp_destroy, | |
c5c25238 | 683 | .get_mtu = esp4_get_mtu, |
1da177e4 | 684 | .input = esp_input, |
1da177e4 LT |
685 | .output = esp_output |
686 | }; | |
687 | ||
32613090 | 688 | static const struct net_protocol esp4_protocol = { |
1da177e4 LT |
689 | .handler = xfrm4_rcv, |
690 | .err_handler = esp4_err, | |
691 | .no_policy = 1, | |
4fb236ba | 692 | .netns_ok = 1, |
1da177e4 LT |
693 | }; |
694 | ||
695 | static int __init esp4_init(void) | |
696 | { | |
1da177e4 | 697 | if (xfrm_register_type(&esp_type, AF_INET) < 0) { |
058bd4d2 | 698 | pr_info("%s: can't add xfrm type\n", __func__); |
1da177e4 LT |
699 | return -EAGAIN; |
700 | } | |
701 | if (inet_add_protocol(&esp4_protocol, IPPROTO_ESP) < 0) { | |
058bd4d2 | 702 | pr_info("%s: can't add protocol\n", __func__); |
1da177e4 LT |
703 | xfrm_unregister_type(&esp_type, AF_INET); |
704 | return -EAGAIN; | |
705 | } | |
706 | return 0; | |
707 | } | |
708 | ||
709 | static void __exit esp4_fini(void) | |
710 | { | |
711 | if (inet_del_protocol(&esp4_protocol, IPPROTO_ESP) < 0) | |
058bd4d2 | 712 | pr_info("%s: can't remove protocol\n", __func__); |
1da177e4 | 713 | if (xfrm_unregister_type(&esp_type, AF_INET) < 0) |
058bd4d2 | 714 | pr_info("%s: can't remove xfrm type\n", __func__); |
1da177e4 LT |
715 | } |
716 | ||
717 | module_init(esp4_init); | |
718 | module_exit(esp4_fini); | |
719 | MODULE_LICENSE("GPL"); | |
d3d6dd3a | 720 | MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP); |