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Commit | Line | Data |
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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 | ||
962fcef3 HX |
26 | struct esp_output_extra { |
27 | __be32 seqhi; | |
28 | u32 esphoff; | |
29 | }; | |
30 | ||
38320c70 HX |
31 | #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) |
32 | ||
d979e20f MW |
33 | static u32 esp4_get_mtu(struct xfrm_state *x, int mtu); |
34 | ||
38320c70 HX |
35 | /* |
36 | * Allocate an AEAD request structure with extra space for SG and IV. | |
37 | * | |
38 | * For alignment considerations the IV is placed at the front, followed | |
39 | * by the request and finally the SG list. | |
40 | * | |
41 | * TODO: Use spare space in skb for this where possible. | |
42 | */ | |
962fcef3 | 43 | static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int extralen) |
38320c70 HX |
44 | { |
45 | unsigned int len; | |
46 | ||
962fcef3 | 47 | len = extralen; |
0dc49e9b SK |
48 | |
49 | len += crypto_aead_ivsize(aead); | |
50 | ||
38320c70 HX |
51 | if (len) { |
52 | len += crypto_aead_alignmask(aead) & | |
53 | ~(crypto_tfm_ctx_alignment() - 1); | |
54 | len = ALIGN(len, crypto_tfm_ctx_alignment()); | |
55 | } | |
56 | ||
7021b2e1 | 57 | len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); |
38320c70 HX |
58 | len = ALIGN(len, __alignof__(struct scatterlist)); |
59 | ||
60 | len += sizeof(struct scatterlist) * nfrags; | |
61 | ||
62 | return kmalloc(len, GFP_ATOMIC); | |
63 | } | |
64 | ||
962fcef3 | 65 | static inline void *esp_tmp_extra(void *tmp) |
0dc49e9b | 66 | { |
962fcef3 | 67 | return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra)); |
0dc49e9b | 68 | } |
962fcef3 HX |
69 | |
70 | static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int extralen) | |
38320c70 HX |
71 | { |
72 | return crypto_aead_ivsize(aead) ? | |
962fcef3 HX |
73 | PTR_ALIGN((u8 *)tmp + extralen, |
74 | crypto_aead_alignmask(aead) + 1) : tmp + extralen; | |
38320c70 HX |
75 | } |
76 | ||
38320c70 HX |
77 | static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) |
78 | { | |
79 | struct aead_request *req; | |
80 | ||
81 | req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), | |
82 | crypto_tfm_ctx_alignment()); | |
83 | aead_request_set_tfm(req, aead); | |
84 | return req; | |
85 | } | |
86 | ||
87 | static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, | |
88 | struct aead_request *req) | |
89 | { | |
90 | return (void *)ALIGN((unsigned long)(req + 1) + | |
91 | crypto_aead_reqsize(aead), | |
92 | __alignof__(struct scatterlist)); | |
93 | } | |
94 | ||
38320c70 HX |
95 | static void esp_output_done(struct crypto_async_request *base, int err) |
96 | { | |
97 | struct sk_buff *skb = base->data; | |
98 | ||
99 | kfree(ESP_SKB_CB(skb)->tmp); | |
100 | xfrm_output_resume(skb, err); | |
101 | } | |
102 | ||
7021b2e1 HX |
103 | /* Move ESP header back into place. */ |
104 | static void esp_restore_header(struct sk_buff *skb, unsigned int offset) | |
105 | { | |
106 | struct ip_esp_hdr *esph = (void *)(skb->data + offset); | |
107 | void *tmp = ESP_SKB_CB(skb)->tmp; | |
962fcef3 | 108 | __be32 *seqhi = esp_tmp_extra(tmp); |
7021b2e1 HX |
109 | |
110 | esph->seq_no = esph->spi; | |
111 | esph->spi = *seqhi; | |
112 | } | |
113 | ||
114 | static void esp_output_restore_header(struct sk_buff *skb) | |
115 | { | |
962fcef3 HX |
116 | void *tmp = ESP_SKB_CB(skb)->tmp; |
117 | struct esp_output_extra *extra = esp_tmp_extra(tmp); | |
118 | ||
119 | esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff - | |
120 | sizeof(__be32)); | |
7021b2e1 HX |
121 | } |
122 | ||
123 | static void esp_output_done_esn(struct crypto_async_request *base, int err) | |
124 | { | |
125 | struct sk_buff *skb = base->data; | |
126 | ||
127 | esp_output_restore_header(skb); | |
128 | esp_output_done(base, err); | |
129 | } | |
130 | ||
1da177e4 LT |
131 | static int esp_output(struct xfrm_state *x, struct sk_buff *skb) |
132 | { | |
133 | int err; | |
962fcef3 | 134 | struct esp_output_extra *extra; |
1da177e4 | 135 | struct ip_esp_hdr *esph; |
38320c70 | 136 | struct crypto_aead *aead; |
7021b2e1 | 137 | struct aead_request *req; |
38320c70 | 138 | struct scatterlist *sg; |
1da177e4 | 139 | struct sk_buff *trailer; |
38320c70 HX |
140 | void *tmp; |
141 | u8 *iv; | |
27a884dc | 142 | u8 *tail; |
1da177e4 LT |
143 | int blksize; |
144 | int clen; | |
145 | int alen; | |
d979e20f | 146 | int plen; |
7021b2e1 | 147 | int ivlen; |
d979e20f | 148 | int tfclen; |
1da177e4 | 149 | int nfrags; |
0dc49e9b | 150 | int assoclen; |
962fcef3 | 151 | int extralen; |
7021b2e1 | 152 | __be64 seqno; |
1da177e4 | 153 | |
7b277b1a | 154 | /* skb is pure payload to encrypt */ |
1da177e4 | 155 | |
1c5ad13f | 156 | aead = x->data; |
38320c70 | 157 | alen = crypto_aead_authsize(aead); |
7021b2e1 | 158 | ivlen = crypto_aead_ivsize(aead); |
38320c70 | 159 | |
d979e20f MW |
160 | tfclen = 0; |
161 | if (x->tfcpad) { | |
162 | struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); | |
163 | u32 padto; | |
164 | ||
165 | padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached)); | |
166 | if (skb->len < padto) | |
167 | tfclen = padto - skb->len; | |
168 | } | |
38320c70 | 169 | blksize = ALIGN(crypto_aead_blocksize(aead), 4); |
d979e20f | 170 | clen = ALIGN(skb->len + 2 + tfclen, blksize); |
d979e20f | 171 | plen = clen - skb->len - tfclen; |
38320c70 | 172 | |
d979e20f MW |
173 | err = skb_cow_data(skb, tfclen + plen + alen, &trailer); |
174 | if (err < 0) | |
38320c70 HX |
175 | goto error; |
176 | nfrags = err; | |
1da177e4 | 177 | |
0dc49e9b | 178 | assoclen = sizeof(*esph); |
962fcef3 | 179 | extralen = 0; |
0dc49e9b SK |
180 | |
181 | if (x->props.flags & XFRM_STATE_ESN) { | |
962fcef3 HX |
182 | extralen += sizeof(*extra); |
183 | assoclen += sizeof(__be32); | |
0dc49e9b SK |
184 | } |
185 | ||
962fcef3 | 186 | tmp = esp_alloc_tmp(aead, nfrags, extralen); |
06848c10 WY |
187 | if (!tmp) { |
188 | err = -ENOMEM; | |
1da177e4 | 189 | goto error; |
06848c10 | 190 | } |
1da177e4 | 191 | |
962fcef3 HX |
192 | extra = esp_tmp_extra(tmp); |
193 | iv = esp_tmp_iv(aead, tmp, extralen); | |
7021b2e1 HX |
194 | req = esp_tmp_req(aead, iv); |
195 | sg = esp_req_sg(aead, req); | |
38320c70 | 196 | |
1da177e4 | 197 | /* Fill padding... */ |
27a884dc | 198 | tail = skb_tail_pointer(trailer); |
d979e20f MW |
199 | if (tfclen) { |
200 | memset(tail, 0, tfclen); | |
201 | tail += tfclen; | |
202 | } | |
1da177e4 LT |
203 | do { |
204 | int i; | |
d979e20f | 205 | for (i = 0; i < plen - 2; i++) |
27a884dc | 206 | tail[i] = i + 1; |
1da177e4 | 207 | } while (0); |
d979e20f MW |
208 | tail[plen - 2] = plen - 2; |
209 | tail[plen - 1] = *skb_mac_header(skb); | |
38320c70 | 210 | pskb_put(skb, trailer, clen - skb->len + alen); |
1da177e4 | 211 | |
7b277b1a | 212 | skb_push(skb, -skb_network_offset(skb)); |
87bdc48d | 213 | esph = ip_esp_hdr(skb); |
37fedd3a | 214 | *skb_mac_header(skb) = IPPROTO_ESP; |
1da177e4 LT |
215 | |
216 | /* this is non-NULL only with UDP Encapsulation */ | |
217 | if (x->encap) { | |
218 | struct xfrm_encap_tmpl *encap = x->encap; | |
219 | struct udphdr *uh; | |
d5a0a1e3 | 220 | __be32 *udpdata32; |
5e226e4d | 221 | __be16 sport, dport; |
38320c70 HX |
222 | int encap_type; |
223 | ||
224 | spin_lock_bh(&x->lock); | |
225 | sport = encap->encap_sport; | |
226 | dport = encap->encap_dport; | |
227 | encap_type = encap->encap_type; | |
228 | spin_unlock_bh(&x->lock); | |
1da177e4 LT |
229 | |
230 | uh = (struct udphdr *)esph; | |
38320c70 HX |
231 | uh->source = sport; |
232 | uh->dest = dport; | |
233 | uh->len = htons(skb->len - skb_transport_offset(skb)); | |
1da177e4 LT |
234 | uh->check = 0; |
235 | ||
38320c70 | 236 | switch (encap_type) { |
1da177e4 LT |
237 | default: |
238 | case UDP_ENCAP_ESPINUDP: | |
239 | esph = (struct ip_esp_hdr *)(uh + 1); | |
240 | break; | |
241 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
d5a0a1e3 | 242 | udpdata32 = (__be32 *)(uh + 1); |
1da177e4 LT |
243 | udpdata32[0] = udpdata32[1] = 0; |
244 | esph = (struct ip_esp_hdr *)(udpdata32 + 2); | |
245 | break; | |
246 | } | |
247 | ||
37fedd3a HX |
248 | *skb_mac_header(skb) = IPPROTO_UDP; |
249 | } | |
1da177e4 | 250 | |
1ce3644a | 251 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); |
1da177e4 | 252 | |
7021b2e1 HX |
253 | aead_request_set_callback(req, 0, esp_output_done, skb); |
254 | ||
255 | /* For ESN we move the header forward by 4 bytes to | |
256 | * accomodate the high bits. We will move it back after | |
257 | * encryption. | |
258 | */ | |
259 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
962fcef3 HX |
260 | extra->esphoff = (unsigned char *)esph - |
261 | skb_transport_header(skb); | |
262 | esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4); | |
263 | extra->seqhi = esph->spi; | |
7021b2e1 HX |
264 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); |
265 | aead_request_set_callback(req, 0, esp_output_done_esn, skb); | |
266 | } | |
267 | ||
268 | esph->spi = x->id.spi; | |
269 | ||
38320c70 HX |
270 | sg_init_table(sg, nfrags); |
271 | skb_to_sgvec(skb, sg, | |
7021b2e1 HX |
272 | (unsigned char *)esph - skb->data, |
273 | assoclen + ivlen + clen + alen); | |
0dc49e9b | 274 | |
7021b2e1 HX |
275 | aead_request_set_crypt(req, sg, sg, ivlen + clen, iv); |
276 | aead_request_set_ad(req, assoclen); | |
277 | ||
278 | seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + | |
279 | ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); | |
280 | ||
281 | memset(iv, 0, ivlen); | |
282 | memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&seqno + 8 - min(ivlen, 8), | |
283 | min(ivlen, 8)); | |
38320c70 HX |
284 | |
285 | ESP_SKB_CB(skb)->tmp = tmp; | |
7021b2e1 HX |
286 | err = crypto_aead_encrypt(req); |
287 | ||
288 | switch (err) { | |
289 | case -EINPROGRESS: | |
38320c70 | 290 | goto error; |
1da177e4 | 291 | |
7021b2e1 | 292 | case -EBUSY: |
38320c70 | 293 | err = NET_XMIT_DROP; |
7021b2e1 HX |
294 | break; |
295 | ||
296 | case 0: | |
297 | if ((x->props.flags & XFRM_STATE_ESN)) | |
298 | esp_output_restore_header(skb); | |
299 | } | |
1da177e4 | 300 | |
38320c70 | 301 | kfree(tmp); |
b7c6538c | 302 | |
1da177e4 LT |
303 | error: |
304 | return err; | |
305 | } | |
306 | ||
38320c70 | 307 | static int esp_input_done2(struct sk_buff *skb, int err) |
1da177e4 | 308 | { |
b71d1d42 | 309 | const struct iphdr *iph; |
38320c70 | 310 | struct xfrm_state *x = xfrm_input_state(skb); |
1c5ad13f | 311 | struct crypto_aead *aead = x->data; |
38320c70 HX |
312 | int alen = crypto_aead_authsize(aead); |
313 | int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
314 | int elen = skb->len - hlen; | |
31a4ab93 | 315 | int ihl; |
4bf05ece | 316 | u8 nexthdr[2]; |
4bf05ece | 317 | int padlen; |
1da177e4 | 318 | |
38320c70 | 319 | kfree(ESP_SKB_CB(skb)->tmp); |
0ebea8ef | 320 | |
6b7326c8 | 321 | if (unlikely(err)) |
668dc8af | 322 | goto out; |
1da177e4 | 323 | |
4bf05ece HX |
324 | if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) |
325 | BUG(); | |
1da177e4 | 326 | |
668dc8af | 327 | err = -EINVAL; |
4bf05ece | 328 | padlen = nexthdr[0]; |
38320c70 | 329 | if (padlen + 2 + alen >= elen) |
4bf05ece | 330 | goto out; |
1da177e4 | 331 | |
e905a9ed | 332 | /* ... check padding bits here. Silly. :-) */ |
1da177e4 | 333 | |
eddc9ec5 | 334 | iph = ip_hdr(skb); |
31a4ab93 HX |
335 | ihl = iph->ihl * 4; |
336 | ||
752c1f4c HX |
337 | if (x->encap) { |
338 | struct xfrm_encap_tmpl *encap = x->encap; | |
d56f90a7 | 339 | struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); |
752c1f4c HX |
340 | |
341 | /* | |
342 | * 1) if the NAT-T peer's IP or port changed then | |
343 | * advertize the change to the keying daemon. | |
344 | * This is an inbound SA, so just compare | |
345 | * SRC ports. | |
346 | */ | |
347 | if (iph->saddr != x->props.saddr.a4 || | |
348 | uh->source != encap->encap_sport) { | |
349 | xfrm_address_t ipaddr; | |
350 | ||
351 | ipaddr.a4 = iph->saddr; | |
352 | km_new_mapping(x, &ipaddr, uh->source); | |
e905a9ed | 353 | |
752c1f4c HX |
354 | /* XXX: perhaps add an extra |
355 | * policy check here, to see | |
356 | * if we should allow or | |
357 | * reject a packet from a | |
358 | * different source | |
359 | * address/port. | |
360 | */ | |
1da177e4 | 361 | } |
e905a9ed | 362 | |
752c1f4c HX |
363 | /* |
364 | * 2) ignore UDP/TCP checksums in case | |
365 | * of NAT-T in Transport Mode, or | |
366 | * perform other post-processing fixes | |
367 | * as per draft-ietf-ipsec-udp-encaps-06, | |
368 | * section 3.1.2 | |
369 | */ | |
8bd17075 | 370 | if (x->props.mode == XFRM_MODE_TRANSPORT) |
752c1f4c | 371 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
1da177e4 LT |
372 | } |
373 | ||
4bf05ece | 374 | pskb_trim(skb, skb->len - alen - padlen - 2); |
38320c70 | 375 | __skb_pull(skb, hlen); |
7143dfac LR |
376 | if (x->props.mode == XFRM_MODE_TUNNEL) |
377 | skb_reset_transport_header(skb); | |
378 | else | |
379 | skb_set_transport_header(skb, -ihl); | |
4bf05ece | 380 | |
38320c70 HX |
381 | err = nexthdr[1]; |
382 | ||
383 | /* RFC4303: Drop dummy packets without any error */ | |
384 | if (err == IPPROTO_NONE) | |
385 | err = -EINVAL; | |
386 | ||
387 | out: | |
388 | return err; | |
389 | } | |
390 | ||
391 | static void esp_input_done(struct crypto_async_request *base, int err) | |
392 | { | |
393 | struct sk_buff *skb = base->data; | |
394 | ||
395 | xfrm_input_resume(skb, esp_input_done2(skb, err)); | |
396 | } | |
397 | ||
7021b2e1 HX |
398 | static void esp_input_restore_header(struct sk_buff *skb) |
399 | { | |
400 | esp_restore_header(skb, 0); | |
401 | __skb_pull(skb, 4); | |
402 | } | |
403 | ||
404 | static void esp_input_done_esn(struct crypto_async_request *base, int err) | |
405 | { | |
406 | struct sk_buff *skb = base->data; | |
407 | ||
408 | esp_input_restore_header(skb); | |
409 | esp_input_done(base, err); | |
410 | } | |
411 | ||
38320c70 HX |
412 | /* |
413 | * Note: detecting truncated vs. non-truncated authentication data is very | |
414 | * expensive, so we only support truncated data, which is the recommended | |
415 | * and common case. | |
416 | */ | |
417 | static int esp_input(struct xfrm_state *x, struct sk_buff *skb) | |
418 | { | |
419 | struct ip_esp_hdr *esph; | |
1c5ad13f | 420 | struct crypto_aead *aead = x->data; |
38320c70 HX |
421 | struct aead_request *req; |
422 | struct sk_buff *trailer; | |
7021b2e1 HX |
423 | int ivlen = crypto_aead_ivsize(aead); |
424 | int elen = skb->len - sizeof(*esph) - ivlen; | |
38320c70 | 425 | int nfrags; |
0dc49e9b | 426 | int assoclen; |
0dc49e9b SK |
427 | int seqhilen; |
428 | __be32 *seqhi; | |
38320c70 HX |
429 | void *tmp; |
430 | u8 *iv; | |
431 | struct scatterlist *sg; | |
38320c70 HX |
432 | int err = -EINVAL; |
433 | ||
7021b2e1 | 434 | if (!pskb_may_pull(skb, sizeof(*esph) + ivlen)) |
38320c70 HX |
435 | goto out; |
436 | ||
437 | if (elen <= 0) | |
438 | goto out; | |
439 | ||
05006e8c FF |
440 | err = skb_cow_data(skb, 0, &trailer); |
441 | if (err < 0) | |
38320c70 | 442 | goto out; |
05006e8c | 443 | |
38320c70 HX |
444 | nfrags = err; |
445 | ||
0dc49e9b | 446 | assoclen = sizeof(*esph); |
0dc49e9b SK |
447 | seqhilen = 0; |
448 | ||
449 | if (x->props.flags & XFRM_STATE_ESN) { | |
0dc49e9b SK |
450 | seqhilen += sizeof(__be32); |
451 | assoclen += seqhilen; | |
452 | } | |
453 | ||
38320c70 | 454 | err = -ENOMEM; |
7021b2e1 | 455 | tmp = esp_alloc_tmp(aead, nfrags, seqhilen); |
38320c70 HX |
456 | if (!tmp) |
457 | goto out; | |
458 | ||
459 | ESP_SKB_CB(skb)->tmp = tmp; | |
962fcef3 | 460 | seqhi = esp_tmp_extra(tmp); |
0dc49e9b | 461 | iv = esp_tmp_iv(aead, tmp, seqhilen); |
38320c70 | 462 | req = esp_tmp_req(aead, iv); |
7021b2e1 | 463 | sg = esp_req_sg(aead, req); |
38320c70 HX |
464 | |
465 | skb->ip_summed = CHECKSUM_NONE; | |
466 | ||
467 | esph = (struct ip_esp_hdr *)skb->data; | |
468 | ||
7021b2e1 | 469 | aead_request_set_callback(req, 0, esp_input_done, skb); |
0dc49e9b | 470 | |
7021b2e1 HX |
471 | /* For ESN we move the header forward by 4 bytes to |
472 | * accomodate the high bits. We will move it back after | |
473 | * decryption. | |
474 | */ | |
0dc49e9b | 475 | if ((x->props.flags & XFRM_STATE_ESN)) { |
7021b2e1 HX |
476 | esph = (void *)skb_push(skb, 4); |
477 | *seqhi = esph->spi; | |
478 | esph->spi = esph->seq_no; | |
479 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.input.hi); | |
480 | aead_request_set_callback(req, 0, esp_input_done_esn, skb); | |
481 | } | |
38320c70 | 482 | |
7021b2e1 HX |
483 | sg_init_table(sg, nfrags); |
484 | skb_to_sgvec(skb, sg, 0, skb->len); | |
485 | ||
486 | aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); | |
487 | aead_request_set_ad(req, assoclen); | |
38320c70 HX |
488 | |
489 | err = crypto_aead_decrypt(req); | |
490 | if (err == -EINPROGRESS) | |
491 | goto out; | |
492 | ||
7021b2e1 HX |
493 | if ((x->props.flags & XFRM_STATE_ESN)) |
494 | esp_input_restore_header(skb); | |
495 | ||
38320c70 | 496 | err = esp_input_done2(skb, err); |
1da177e4 LT |
497 | |
498 | out: | |
668dc8af | 499 | return err; |
1da177e4 LT |
500 | } |
501 | ||
c5c25238 | 502 | static u32 esp4_get_mtu(struct xfrm_state *x, int mtu) |
1da177e4 | 503 | { |
1c5ad13f MK |
504 | struct crypto_aead *aead = x->data; |
505 | u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); | |
91657eaf | 506 | unsigned int net_adj; |
0a69452c DB |
507 | |
508 | switch (x->props.mode) { | |
0a69452c | 509 | case XFRM_MODE_TRANSPORT: |
0a69452c | 510 | case XFRM_MODE_BEET: |
91657eaf | 511 | net_adj = sizeof(struct iphdr); |
0a69452c | 512 | break; |
91657eaf BP |
513 | case XFRM_MODE_TUNNEL: |
514 | net_adj = 0; | |
515 | break; | |
516 | default: | |
517 | BUG(); | |
1da177e4 | 518 | } |
0a69452c | 519 | |
1c5ad13f | 520 | return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - |
123b0d1b | 521 | net_adj) & ~(blksize - 1)) + net_adj - 2; |
1da177e4 LT |
522 | } |
523 | ||
827789cb | 524 | static int esp4_err(struct sk_buff *skb, u32 info) |
1da177e4 | 525 | { |
4fb236ba | 526 | struct net *net = dev_net(skb->dev); |
b71d1d42 | 527 | const struct iphdr *iph = (const struct iphdr *)skb->data; |
d9319100 | 528 | struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); |
1da177e4 LT |
529 | struct xfrm_state *x; |
530 | ||
55be7a9c DM |
531 | switch (icmp_hdr(skb)->type) { |
532 | case ICMP_DEST_UNREACH: | |
533 | if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) | |
827789cb | 534 | return 0; |
55be7a9c DM |
535 | case ICMP_REDIRECT: |
536 | break; | |
537 | default: | |
827789cb | 538 | return 0; |
55be7a9c | 539 | } |
1da177e4 | 540 | |
b71d1d42 ED |
541 | x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, |
542 | esph->spi, IPPROTO_ESP, AF_INET); | |
1da177e4 | 543 | if (!x) |
827789cb | 544 | return 0; |
55be7a9c | 545 | |
387aa65a | 546 | if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) |
55be7a9c | 547 | ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0); |
387aa65a | 548 | else |
55be7a9c | 549 | ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0); |
1da177e4 | 550 | xfrm_state_put(x); |
827789cb SK |
551 | |
552 | return 0; | |
1da177e4 LT |
553 | } |
554 | ||
555 | static void esp_destroy(struct xfrm_state *x) | |
556 | { | |
1c5ad13f | 557 | struct crypto_aead *aead = x->data; |
1da177e4 | 558 | |
1c5ad13f | 559 | if (!aead) |
1da177e4 LT |
560 | return; |
561 | ||
1c5ad13f | 562 | crypto_free_aead(aead); |
1da177e4 LT |
563 | } |
564 | ||
1a6509d9 | 565 | static int esp_init_aead(struct xfrm_state *x) |
1da177e4 | 566 | { |
7021b2e1 | 567 | char aead_name[CRYPTO_MAX_ALG_NAME]; |
1a6509d9 HX |
568 | struct crypto_aead *aead; |
569 | int err; | |
570 | ||
7021b2e1 HX |
571 | err = -ENAMETOOLONG; |
572 | if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", | |
573 | x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
574 | goto error; | |
575 | ||
576 | aead = crypto_alloc_aead(aead_name, 0, 0); | |
1a6509d9 HX |
577 | err = PTR_ERR(aead); |
578 | if (IS_ERR(aead)) | |
579 | goto error; | |
580 | ||
1c5ad13f | 581 | x->data = aead; |
1a6509d9 HX |
582 | |
583 | err = crypto_aead_setkey(aead, x->aead->alg_key, | |
584 | (x->aead->alg_key_len + 7) / 8); | |
585 | if (err) | |
586 | goto error; | |
587 | ||
588 | err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); | |
589 | if (err) | |
590 | goto error; | |
591 | ||
592 | error: | |
593 | return err; | |
594 | } | |
595 | ||
596 | static int esp_init_authenc(struct xfrm_state *x) | |
597 | { | |
38320c70 HX |
598 | struct crypto_aead *aead; |
599 | struct crypto_authenc_key_param *param; | |
600 | struct rtattr *rta; | |
601 | char *key; | |
602 | char *p; | |
603 | char authenc_name[CRYPTO_MAX_ALG_NAME]; | |
38320c70 HX |
604 | unsigned int keylen; |
605 | int err; | |
1da177e4 | 606 | |
1a6509d9 | 607 | err = -EINVAL; |
51456b29 | 608 | if (!x->ealg) |
1a6509d9 | 609 | goto error; |
38320c70 | 610 | |
1a6509d9 | 611 | err = -ENAMETOOLONG; |
0dc49e9b SK |
612 | |
613 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
614 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
7021b2e1 HX |
615 | "%s%sauthencesn(%s,%s)%s", |
616 | x->geniv ?: "", x->geniv ? "(" : "", | |
0dc49e9b | 617 | x->aalg ? x->aalg->alg_name : "digest_null", |
7021b2e1 HX |
618 | x->ealg->alg_name, |
619 | x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) | |
0dc49e9b SK |
620 | goto error; |
621 | } else { | |
622 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
7021b2e1 HX |
623 | "%s%sauthenc(%s,%s)%s", |
624 | x->geniv ?: "", x->geniv ? "(" : "", | |
0dc49e9b | 625 | x->aalg ? x->aalg->alg_name : "digest_null", |
7021b2e1 HX |
626 | x->ealg->alg_name, |
627 | x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) | |
0dc49e9b SK |
628 | goto error; |
629 | } | |
38320c70 HX |
630 | |
631 | aead = crypto_alloc_aead(authenc_name, 0, 0); | |
632 | err = PTR_ERR(aead); | |
633 | if (IS_ERR(aead)) | |
634 | goto error; | |
635 | ||
1c5ad13f | 636 | x->data = aead; |
38320c70 HX |
637 | |
638 | keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + | |
639 | (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); | |
640 | err = -ENOMEM; | |
641 | key = kmalloc(keylen, GFP_KERNEL); | |
642 | if (!key) | |
643 | goto error; | |
644 | ||
645 | p = key; | |
646 | rta = (void *)p; | |
647 | rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; | |
648 | rta->rta_len = RTA_LENGTH(sizeof(*param)); | |
649 | param = RTA_DATA(rta); | |
650 | p += RTA_SPACE(sizeof(*param)); | |
651 | ||
1da177e4 LT |
652 | if (x->aalg) { |
653 | struct xfrm_algo_desc *aalg_desc; | |
654 | ||
38320c70 HX |
655 | memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); |
656 | p += (x->aalg->alg_key_len + 7) / 8; | |
1da177e4 LT |
657 | |
658 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); | |
659 | BUG_ON(!aalg_desc); | |
660 | ||
38320c70 | 661 | err = -EINVAL; |
45083497 | 662 | if (aalg_desc->uinfo.auth.icv_fullbits / 8 != |
38320c70 | 663 | crypto_aead_authsize(aead)) { |
45083497 JP |
664 | pr_info("ESP: %s digestsize %u != %hu\n", |
665 | x->aalg->alg_name, | |
666 | crypto_aead_authsize(aead), | |
667 | aalg_desc->uinfo.auth.icv_fullbits / 8); | |
38320c70 | 668 | goto free_key; |
1da177e4 LT |
669 | } |
670 | ||
38320c70 | 671 | err = crypto_aead_setauthsize( |
8f8a088c | 672 | aead, x->aalg->alg_trunc_len / 8); |
38320c70 HX |
673 | if (err) |
674 | goto free_key; | |
1da177e4 | 675 | } |
4b7137ff | 676 | |
38320c70 HX |
677 | param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); |
678 | memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); | |
679 | ||
680 | err = crypto_aead_setkey(aead, key, keylen); | |
681 | ||
682 | free_key: | |
683 | kfree(key); | |
684 | ||
1a6509d9 HX |
685 | error: |
686 | return err; | |
687 | } | |
688 | ||
689 | static int esp_init_state(struct xfrm_state *x) | |
690 | { | |
1a6509d9 HX |
691 | struct crypto_aead *aead; |
692 | u32 align; | |
693 | int err; | |
694 | ||
1c5ad13f | 695 | x->data = NULL; |
1a6509d9 HX |
696 | |
697 | if (x->aead) | |
698 | err = esp_init_aead(x); | |
699 | else | |
700 | err = esp_init_authenc(x); | |
701 | ||
38320c70 | 702 | if (err) |
1da177e4 | 703 | goto error; |
38320c70 | 704 | |
1c5ad13f | 705 | aead = x->data; |
1a6509d9 | 706 | |
38320c70 HX |
707 | x->props.header_len = sizeof(struct ip_esp_hdr) + |
708 | crypto_aead_ivsize(aead); | |
7e49e6de | 709 | if (x->props.mode == XFRM_MODE_TUNNEL) |
1da177e4 | 710 | x->props.header_len += sizeof(struct iphdr); |
eb49e630 | 711 | else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6) |
ac758e3c | 712 | x->props.header_len += IPV4_BEET_PHMAXLEN; |
1da177e4 LT |
713 | if (x->encap) { |
714 | struct xfrm_encap_tmpl *encap = x->encap; | |
715 | ||
716 | switch (encap->encap_type) { | |
717 | default: | |
718 | goto error; | |
719 | case UDP_ENCAP_ESPINUDP: | |
720 | x->props.header_len += sizeof(struct udphdr); | |
721 | break; | |
722 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
723 | x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32); | |
724 | break; | |
725 | } | |
726 | } | |
38320c70 HX |
727 | |
728 | align = ALIGN(crypto_aead_blocksize(aead), 4); | |
1c5ad13f | 729 | x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); |
1da177e4 LT |
730 | |
731 | error: | |
38320c70 | 732 | return err; |
1da177e4 LT |
733 | } |
734 | ||
827789cb SK |
735 | static int esp4_rcv_cb(struct sk_buff *skb, int err) |
736 | { | |
737 | return 0; | |
738 | } | |
739 | ||
533cb5b0 | 740 | static const struct xfrm_type esp_type = |
1da177e4 LT |
741 | { |
742 | .description = "ESP4", | |
743 | .owner = THIS_MODULE, | |
744 | .proto = IPPROTO_ESP, | |
436a0a40 | 745 | .flags = XFRM_TYPE_REPLAY_PROT, |
1da177e4 LT |
746 | .init_state = esp_init_state, |
747 | .destructor = esp_destroy, | |
c5c25238 | 748 | .get_mtu = esp4_get_mtu, |
1da177e4 | 749 | .input = esp_input, |
1da177e4 LT |
750 | .output = esp_output |
751 | }; | |
752 | ||
827789cb | 753 | static struct xfrm4_protocol esp4_protocol = { |
1da177e4 | 754 | .handler = xfrm4_rcv, |
827789cb SK |
755 | .input_handler = xfrm_input, |
756 | .cb_handler = esp4_rcv_cb, | |
1da177e4 | 757 | .err_handler = esp4_err, |
827789cb | 758 | .priority = 0, |
1da177e4 LT |
759 | }; |
760 | ||
761 | static int __init esp4_init(void) | |
762 | { | |
1da177e4 | 763 | if (xfrm_register_type(&esp_type, AF_INET) < 0) { |
058bd4d2 | 764 | pr_info("%s: can't add xfrm type\n", __func__); |
1da177e4 LT |
765 | return -EAGAIN; |
766 | } | |
827789cb | 767 | if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) { |
058bd4d2 | 768 | pr_info("%s: can't add protocol\n", __func__); |
1da177e4 LT |
769 | xfrm_unregister_type(&esp_type, AF_INET); |
770 | return -EAGAIN; | |
771 | } | |
772 | return 0; | |
773 | } | |
774 | ||
775 | static void __exit esp4_fini(void) | |
776 | { | |
827789cb | 777 | if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0) |
058bd4d2 | 778 | pr_info("%s: can't remove protocol\n", __func__); |
1da177e4 | 779 | if (xfrm_unregister_type(&esp_type, AF_INET) < 0) |
058bd4d2 | 780 | pr_info("%s: can't remove xfrm type\n", __func__); |
1da177e4 LT |
781 | } |
782 | ||
783 | module_init(esp4_init); | |
784 | module_exit(esp4_fini); | |
785 | MODULE_LICENSE("GPL"); | |
d3d6dd3a | 786 | MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP); |