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Commit | Line | Data |
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38320c70 HX |
1 | #include <crypto/aead.h> |
2 | #include <crypto/authenc.h> | |
6b7326c8 | 3 | #include <linux/err.h> |
1da177e4 LT |
4 | #include <linux/module.h> |
5 | #include <net/ip.h> | |
6 | #include <net/xfrm.h> | |
7 | #include <net/esp.h> | |
72998d8c | 8 | #include <linux/scatterlist.h> |
a02a6422 | 9 | #include <linux/kernel.h> |
1da177e4 | 10 | #include <linux/pfkeyv2.h> |
38320c70 HX |
11 | #include <linux/rtnetlink.h> |
12 | #include <linux/slab.h> | |
b7c6538c | 13 | #include <linux/spinlock.h> |
2017a72c | 14 | #include <linux/in6.h> |
1da177e4 | 15 | #include <net/icmp.h> |
14c85021 | 16 | #include <net/protocol.h> |
1da177e4 LT |
17 | #include <net/udp.h> |
18 | ||
38320c70 HX |
19 | struct esp_skb_cb { |
20 | struct xfrm_skb_cb xfrm; | |
21 | void *tmp; | |
22 | }; | |
23 | ||
24 | #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) | |
25 | ||
d979e20f MW |
26 | static u32 esp4_get_mtu(struct xfrm_state *x, int mtu); |
27 | ||
38320c70 HX |
28 | /* |
29 | * Allocate an AEAD request structure with extra space for SG and IV. | |
30 | * | |
31 | * For alignment considerations the IV is placed at the front, followed | |
32 | * by the request and finally the SG list. | |
33 | * | |
34 | * TODO: Use spare space in skb for this where possible. | |
35 | */ | |
0dc49e9b | 36 | static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqhilen) |
38320c70 HX |
37 | { |
38 | unsigned int len; | |
39 | ||
0dc49e9b SK |
40 | len = seqhilen; |
41 | ||
42 | len += crypto_aead_ivsize(aead); | |
43 | ||
38320c70 HX |
44 | if (len) { |
45 | len += crypto_aead_alignmask(aead) & | |
46 | ~(crypto_tfm_ctx_alignment() - 1); | |
47 | len = ALIGN(len, crypto_tfm_ctx_alignment()); | |
48 | } | |
49 | ||
50 | len += sizeof(struct aead_givcrypt_request) + crypto_aead_reqsize(aead); | |
51 | len = ALIGN(len, __alignof__(struct scatterlist)); | |
52 | ||
53 | len += sizeof(struct scatterlist) * nfrags; | |
54 | ||
55 | return kmalloc(len, GFP_ATOMIC); | |
56 | } | |
57 | ||
0dc49e9b SK |
58 | static inline __be32 *esp_tmp_seqhi(void *tmp) |
59 | { | |
60 | return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); | |
61 | } | |
62 | static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) | |
38320c70 HX |
63 | { |
64 | return crypto_aead_ivsize(aead) ? | |
0dc49e9b SK |
65 | PTR_ALIGN((u8 *)tmp + seqhilen, |
66 | crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; | |
38320c70 HX |
67 | } |
68 | ||
69 | static inline struct aead_givcrypt_request *esp_tmp_givreq( | |
70 | struct crypto_aead *aead, u8 *iv) | |
71 | { | |
72 | struct aead_givcrypt_request *req; | |
73 | ||
74 | req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), | |
75 | crypto_tfm_ctx_alignment()); | |
76 | aead_givcrypt_set_tfm(req, aead); | |
77 | return req; | |
78 | } | |
79 | ||
80 | static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) | |
81 | { | |
82 | struct aead_request *req; | |
83 | ||
84 | req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), | |
85 | crypto_tfm_ctx_alignment()); | |
86 | aead_request_set_tfm(req, aead); | |
87 | return req; | |
88 | } | |
89 | ||
90 | static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, | |
91 | struct aead_request *req) | |
92 | { | |
93 | return (void *)ALIGN((unsigned long)(req + 1) + | |
94 | crypto_aead_reqsize(aead), | |
95 | __alignof__(struct scatterlist)); | |
96 | } | |
97 | ||
98 | static inline struct scatterlist *esp_givreq_sg( | |
99 | struct crypto_aead *aead, struct aead_givcrypt_request *req) | |
100 | { | |
101 | return (void *)ALIGN((unsigned long)(req + 1) + | |
102 | crypto_aead_reqsize(aead), | |
103 | __alignof__(struct scatterlist)); | |
104 | } | |
105 | ||
106 | static void esp_output_done(struct crypto_async_request *base, int err) | |
107 | { | |
108 | struct sk_buff *skb = base->data; | |
109 | ||
110 | kfree(ESP_SKB_CB(skb)->tmp); | |
111 | xfrm_output_resume(skb, err); | |
112 | } | |
113 | ||
1da177e4 LT |
114 | static int esp_output(struct xfrm_state *x, struct sk_buff *skb) |
115 | { | |
116 | int err; | |
1da177e4 | 117 | struct ip_esp_hdr *esph; |
38320c70 HX |
118 | struct crypto_aead *aead; |
119 | struct aead_givcrypt_request *req; | |
120 | struct scatterlist *sg; | |
121 | struct scatterlist *asg; | |
1da177e4 LT |
122 | struct esp_data *esp; |
123 | struct sk_buff *trailer; | |
38320c70 HX |
124 | void *tmp; |
125 | u8 *iv; | |
27a884dc | 126 | u8 *tail; |
1da177e4 LT |
127 | int blksize; |
128 | int clen; | |
129 | int alen; | |
d979e20f MW |
130 | int plen; |
131 | int tfclen; | |
1da177e4 | 132 | int nfrags; |
0dc49e9b SK |
133 | int assoclen; |
134 | int sglists; | |
135 | int seqhilen; | |
136 | __be32 *seqhi; | |
1da177e4 | 137 | |
7b277b1a | 138 | /* skb is pure payload to encrypt */ |
1da177e4 LT |
139 | |
140 | err = -ENOMEM; | |
141 | ||
1da177e4 | 142 | esp = x->data; |
38320c70 HX |
143 | aead = esp->aead; |
144 | alen = crypto_aead_authsize(aead); | |
145 | ||
d979e20f MW |
146 | tfclen = 0; |
147 | if (x->tfcpad) { | |
148 | struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); | |
149 | u32 padto; | |
150 | ||
151 | padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached)); | |
152 | if (skb->len < padto) | |
153 | tfclen = padto - skb->len; | |
154 | } | |
38320c70 | 155 | blksize = ALIGN(crypto_aead_blocksize(aead), 4); |
d979e20f | 156 | clen = ALIGN(skb->len + 2 + tfclen, blksize); |
38320c70 HX |
157 | if (esp->padlen) |
158 | clen = ALIGN(clen, esp->padlen); | |
d979e20f | 159 | plen = clen - skb->len - tfclen; |
38320c70 | 160 | |
d979e20f MW |
161 | err = skb_cow_data(skb, tfclen + plen + alen, &trailer); |
162 | if (err < 0) | |
38320c70 HX |
163 | goto error; |
164 | nfrags = err; | |
1da177e4 | 165 | |
0dc49e9b SK |
166 | assoclen = sizeof(*esph); |
167 | sglists = 1; | |
168 | seqhilen = 0; | |
169 | ||
170 | if (x->props.flags & XFRM_STATE_ESN) { | |
171 | sglists += 2; | |
172 | seqhilen += sizeof(__be32); | |
173 | assoclen += seqhilen; | |
174 | } | |
175 | ||
176 | tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); | |
38320c70 | 177 | if (!tmp) |
1da177e4 LT |
178 | goto error; |
179 | ||
0dc49e9b SK |
180 | seqhi = esp_tmp_seqhi(tmp); |
181 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 HX |
182 | req = esp_tmp_givreq(aead, iv); |
183 | asg = esp_givreq_sg(aead, req); | |
0dc49e9b | 184 | sg = asg + sglists; |
38320c70 | 185 | |
1da177e4 | 186 | /* Fill padding... */ |
27a884dc | 187 | tail = skb_tail_pointer(trailer); |
d979e20f MW |
188 | if (tfclen) { |
189 | memset(tail, 0, tfclen); | |
190 | tail += tfclen; | |
191 | } | |
1da177e4 LT |
192 | do { |
193 | int i; | |
d979e20f | 194 | for (i = 0; i < plen - 2; i++) |
27a884dc | 195 | tail[i] = i + 1; |
1da177e4 | 196 | } while (0); |
d979e20f MW |
197 | tail[plen - 2] = plen - 2; |
198 | tail[plen - 1] = *skb_mac_header(skb); | |
38320c70 | 199 | pskb_put(skb, trailer, clen - skb->len + alen); |
1da177e4 | 200 | |
7b277b1a | 201 | skb_push(skb, -skb_network_offset(skb)); |
87bdc48d | 202 | esph = ip_esp_hdr(skb); |
37fedd3a | 203 | *skb_mac_header(skb) = IPPROTO_ESP; |
1da177e4 LT |
204 | |
205 | /* this is non-NULL only with UDP Encapsulation */ | |
206 | if (x->encap) { | |
207 | struct xfrm_encap_tmpl *encap = x->encap; | |
208 | struct udphdr *uh; | |
d5a0a1e3 | 209 | __be32 *udpdata32; |
5e226e4d | 210 | __be16 sport, dport; |
38320c70 HX |
211 | int encap_type; |
212 | ||
213 | spin_lock_bh(&x->lock); | |
214 | sport = encap->encap_sport; | |
215 | dport = encap->encap_dport; | |
216 | encap_type = encap->encap_type; | |
217 | spin_unlock_bh(&x->lock); | |
1da177e4 LT |
218 | |
219 | uh = (struct udphdr *)esph; | |
38320c70 HX |
220 | uh->source = sport; |
221 | uh->dest = dport; | |
222 | uh->len = htons(skb->len - skb_transport_offset(skb)); | |
1da177e4 LT |
223 | uh->check = 0; |
224 | ||
38320c70 | 225 | switch (encap_type) { |
1da177e4 LT |
226 | default: |
227 | case UDP_ENCAP_ESPINUDP: | |
228 | esph = (struct ip_esp_hdr *)(uh + 1); | |
229 | break; | |
230 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
d5a0a1e3 | 231 | udpdata32 = (__be32 *)(uh + 1); |
1da177e4 LT |
232 | udpdata32[0] = udpdata32[1] = 0; |
233 | esph = (struct ip_esp_hdr *)(udpdata32 + 2); | |
234 | break; | |
235 | } | |
236 | ||
37fedd3a HX |
237 | *skb_mac_header(skb) = IPPROTO_UDP; |
238 | } | |
1da177e4 LT |
239 | |
240 | esph->spi = x->id.spi; | |
1ce3644a | 241 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); |
1da177e4 | 242 | |
38320c70 HX |
243 | sg_init_table(sg, nfrags); |
244 | skb_to_sgvec(skb, sg, | |
245 | esph->enc_data + crypto_aead_ivsize(aead) - skb->data, | |
246 | clen + alen); | |
0dc49e9b SK |
247 | |
248 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
249 | sg_init_table(asg, 3); | |
250 | sg_set_buf(asg, &esph->spi, sizeof(__be32)); | |
251 | *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); | |
252 | sg_set_buf(asg + 1, seqhi, seqhilen); | |
253 | sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); | |
254 | } else | |
255 | sg_init_one(asg, esph, sizeof(*esph)); | |
38320c70 HX |
256 | |
257 | aead_givcrypt_set_callback(req, 0, esp_output_done, skb); | |
258 | aead_givcrypt_set_crypt(req, sg, sg, clen, iv); | |
0dc49e9b | 259 | aead_givcrypt_set_assoc(req, asg, assoclen); |
b318e0e4 | 260 | aead_givcrypt_set_giv(req, esph->enc_data, |
1ce3644a | 261 | XFRM_SKB_CB(skb)->seq.output.low); |
38320c70 HX |
262 | |
263 | ESP_SKB_CB(skb)->tmp = tmp; | |
264 | err = crypto_aead_givencrypt(req); | |
265 | if (err == -EINPROGRESS) | |
266 | goto error; | |
1da177e4 | 267 | |
38320c70 HX |
268 | if (err == -EBUSY) |
269 | err = NET_XMIT_DROP; | |
1da177e4 | 270 | |
38320c70 | 271 | kfree(tmp); |
b7c6538c | 272 | |
1da177e4 LT |
273 | error: |
274 | return err; | |
275 | } | |
276 | ||
38320c70 | 277 | static int esp_input_done2(struct sk_buff *skb, int err) |
1da177e4 | 278 | { |
b71d1d42 | 279 | const struct iphdr *iph; |
38320c70 | 280 | struct xfrm_state *x = xfrm_input_state(skb); |
1da177e4 | 281 | struct esp_data *esp = x->data; |
38320c70 HX |
282 | struct crypto_aead *aead = esp->aead; |
283 | int alen = crypto_aead_authsize(aead); | |
284 | int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
285 | int elen = skb->len - hlen; | |
31a4ab93 | 286 | int ihl; |
4bf05ece | 287 | u8 nexthdr[2]; |
4bf05ece | 288 | int padlen; |
1da177e4 | 289 | |
38320c70 | 290 | kfree(ESP_SKB_CB(skb)->tmp); |
0ebea8ef | 291 | |
6b7326c8 | 292 | if (unlikely(err)) |
668dc8af | 293 | goto out; |
1da177e4 | 294 | |
4bf05ece HX |
295 | if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) |
296 | BUG(); | |
1da177e4 | 297 | |
668dc8af | 298 | err = -EINVAL; |
4bf05ece | 299 | padlen = nexthdr[0]; |
38320c70 | 300 | if (padlen + 2 + alen >= elen) |
4bf05ece | 301 | goto out; |
1da177e4 | 302 | |
e905a9ed | 303 | /* ... check padding bits here. Silly. :-) */ |
1da177e4 | 304 | |
eddc9ec5 | 305 | iph = ip_hdr(skb); |
31a4ab93 HX |
306 | ihl = iph->ihl * 4; |
307 | ||
752c1f4c HX |
308 | if (x->encap) { |
309 | struct xfrm_encap_tmpl *encap = x->encap; | |
d56f90a7 | 310 | struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); |
752c1f4c HX |
311 | |
312 | /* | |
313 | * 1) if the NAT-T peer's IP or port changed then | |
314 | * advertize the change to the keying daemon. | |
315 | * This is an inbound SA, so just compare | |
316 | * SRC ports. | |
317 | */ | |
318 | if (iph->saddr != x->props.saddr.a4 || | |
319 | uh->source != encap->encap_sport) { | |
320 | xfrm_address_t ipaddr; | |
321 | ||
322 | ipaddr.a4 = iph->saddr; | |
323 | km_new_mapping(x, &ipaddr, uh->source); | |
e905a9ed | 324 | |
752c1f4c HX |
325 | /* XXX: perhaps add an extra |
326 | * policy check here, to see | |
327 | * if we should allow or | |
328 | * reject a packet from a | |
329 | * different source | |
330 | * address/port. | |
331 | */ | |
1da177e4 | 332 | } |
e905a9ed | 333 | |
752c1f4c HX |
334 | /* |
335 | * 2) ignore UDP/TCP checksums in case | |
336 | * of NAT-T in Transport Mode, or | |
337 | * perform other post-processing fixes | |
338 | * as per draft-ietf-ipsec-udp-encaps-06, | |
339 | * section 3.1.2 | |
340 | */ | |
8bd17075 | 341 | if (x->props.mode == XFRM_MODE_TRANSPORT) |
752c1f4c | 342 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
1da177e4 LT |
343 | } |
344 | ||
4bf05ece | 345 | pskb_trim(skb, skb->len - alen - padlen - 2); |
38320c70 | 346 | __skb_pull(skb, hlen); |
967b05f6 | 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; | |
374 | struct esp_data *esp = x->data; | |
375 | struct crypto_aead *aead = esp->aead; | |
376 | struct aead_request *req; | |
377 | struct sk_buff *trailer; | |
378 | int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead); | |
379 | int nfrags; | |
0dc49e9b SK |
380 | int assoclen; |
381 | int sglists; | |
382 | int seqhilen; | |
383 | __be32 *seqhi; | |
38320c70 HX |
384 | void *tmp; |
385 | u8 *iv; | |
386 | struct scatterlist *sg; | |
387 | struct scatterlist *asg; | |
388 | int err = -EINVAL; | |
389 | ||
920fc941 | 390 | if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) |
38320c70 HX |
391 | goto out; |
392 | ||
393 | if (elen <= 0) | |
394 | goto out; | |
395 | ||
396 | if ((err = skb_cow_data(skb, 0, &trailer)) < 0) | |
397 | goto out; | |
398 | nfrags = err; | |
399 | ||
0dc49e9b SK |
400 | assoclen = sizeof(*esph); |
401 | sglists = 1; | |
402 | seqhilen = 0; | |
403 | ||
404 | if (x->props.flags & XFRM_STATE_ESN) { | |
405 | sglists += 2; | |
406 | seqhilen += sizeof(__be32); | |
407 | assoclen += seqhilen; | |
408 | } | |
409 | ||
38320c70 | 410 | err = -ENOMEM; |
0dc49e9b | 411 | tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); |
38320c70 HX |
412 | if (!tmp) |
413 | goto out; | |
414 | ||
415 | ESP_SKB_CB(skb)->tmp = tmp; | |
0dc49e9b SK |
416 | seqhi = esp_tmp_seqhi(tmp); |
417 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 HX |
418 | req = esp_tmp_req(aead, iv); |
419 | asg = esp_req_sg(aead, req); | |
0dc49e9b | 420 | sg = asg + sglists; |
38320c70 HX |
421 | |
422 | skb->ip_summed = CHECKSUM_NONE; | |
423 | ||
424 | esph = (struct ip_esp_hdr *)skb->data; | |
425 | ||
426 | /* Get ivec. This can be wrong, check against another impls. */ | |
427 | iv = esph->enc_data; | |
428 | ||
429 | sg_init_table(sg, nfrags); | |
430 | skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen); | |
0dc49e9b SK |
431 | |
432 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
433 | sg_init_table(asg, 3); | |
434 | sg_set_buf(asg, &esph->spi, sizeof(__be32)); | |
435 | *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; | |
436 | sg_set_buf(asg + 1, seqhi, seqhilen); | |
437 | sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); | |
438 | } else | |
439 | sg_init_one(asg, esph, sizeof(*esph)); | |
38320c70 HX |
440 | |
441 | aead_request_set_callback(req, 0, esp_input_done, skb); | |
442 | aead_request_set_crypt(req, sg, sg, elen, iv); | |
0dc49e9b | 443 | aead_request_set_assoc(req, asg, assoclen); |
38320c70 HX |
444 | |
445 | err = crypto_aead_decrypt(req); | |
446 | if (err == -EINPROGRESS) | |
447 | goto out; | |
448 | ||
449 | err = esp_input_done2(skb, err); | |
1da177e4 LT |
450 | |
451 | out: | |
668dc8af | 452 | return err; |
1da177e4 LT |
453 | } |
454 | ||
c5c25238 | 455 | static u32 esp4_get_mtu(struct xfrm_state *x, int mtu) |
1da177e4 LT |
456 | { |
457 | struct esp_data *esp = x->data; | |
38320c70 HX |
458 | u32 blksize = ALIGN(crypto_aead_blocksize(esp->aead), 4); |
459 | u32 align = max_t(u32, blksize, esp->padlen); | |
c5c25238 PM |
460 | u32 rem; |
461 | ||
38320c70 | 462 | mtu -= x->props.header_len + crypto_aead_authsize(esp->aead); |
c5c25238 PM |
463 | rem = mtu & (align - 1); |
464 | mtu &= ~(align - 1); | |
0a69452c DB |
465 | |
466 | switch (x->props.mode) { | |
467 | case XFRM_MODE_TUNNEL: | |
0a69452c DB |
468 | break; |
469 | default: | |
470 | case XFRM_MODE_TRANSPORT: | |
471 | /* The worst case */ | |
c5c25238 PM |
472 | mtu -= blksize - 4; |
473 | mtu += min_t(u32, blksize - 4, rem); | |
0a69452c DB |
474 | break; |
475 | case XFRM_MODE_BEET: | |
e905a9ed | 476 | /* The worst case. */ |
c5c25238 | 477 | mtu += min_t(u32, IPV4_BEET_PHMAXLEN, rem); |
0a69452c | 478 | break; |
1da177e4 | 479 | } |
0a69452c | 480 | |
c5c25238 | 481 | return mtu - 2; |
1da177e4 LT |
482 | } |
483 | ||
484 | static void esp4_err(struct sk_buff *skb, u32 info) | |
485 | { | |
4fb236ba | 486 | struct net *net = dev_net(skb->dev); |
b71d1d42 | 487 | const struct iphdr *iph = (const struct iphdr *)skb->data; |
d9319100 | 488 | struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); |
1da177e4 LT |
489 | struct xfrm_state *x; |
490 | ||
88c7664f ACM |
491 | if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH || |
492 | icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) | |
1da177e4 LT |
493 | return; |
494 | ||
b71d1d42 ED |
495 | x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, |
496 | esph->spi, IPPROTO_ESP, AF_INET); | |
1da177e4 LT |
497 | if (!x) |
498 | return; | |
64ce2073 PM |
499 | NETDEBUG(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%08x\n", |
500 | ntohl(esph->spi), ntohl(iph->daddr)); | |
1da177e4 LT |
501 | xfrm_state_put(x); |
502 | } | |
503 | ||
504 | static void esp_destroy(struct xfrm_state *x) | |
505 | { | |
506 | struct esp_data *esp = x->data; | |
507 | ||
508 | if (!esp) | |
509 | return; | |
510 | ||
38320c70 | 511 | crypto_free_aead(esp->aead); |
1da177e4 LT |
512 | kfree(esp); |
513 | } | |
514 | ||
1a6509d9 | 515 | static int esp_init_aead(struct xfrm_state *x) |
1da177e4 | 516 | { |
1a6509d9 HX |
517 | struct esp_data *esp = x->data; |
518 | struct crypto_aead *aead; | |
519 | int err; | |
520 | ||
521 | aead = crypto_alloc_aead(x->aead->alg_name, 0, 0); | |
522 | err = PTR_ERR(aead); | |
523 | if (IS_ERR(aead)) | |
524 | goto error; | |
525 | ||
526 | esp->aead = aead; | |
527 | ||
528 | err = crypto_aead_setkey(aead, x->aead->alg_key, | |
529 | (x->aead->alg_key_len + 7) / 8); | |
530 | if (err) | |
531 | goto error; | |
532 | ||
533 | err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); | |
534 | if (err) | |
535 | goto error; | |
536 | ||
537 | error: | |
538 | return err; | |
539 | } | |
540 | ||
541 | static int esp_init_authenc(struct xfrm_state *x) | |
542 | { | |
543 | struct esp_data *esp = x->data; | |
38320c70 HX |
544 | struct crypto_aead *aead; |
545 | struct crypto_authenc_key_param *param; | |
546 | struct rtattr *rta; | |
547 | char *key; | |
548 | char *p; | |
549 | char authenc_name[CRYPTO_MAX_ALG_NAME]; | |
38320c70 HX |
550 | unsigned int keylen; |
551 | int err; | |
1da177e4 | 552 | |
1a6509d9 | 553 | err = -EINVAL; |
1da177e4 | 554 | if (x->ealg == NULL) |
1a6509d9 | 555 | goto error; |
38320c70 | 556 | |
1a6509d9 | 557 | err = -ENAMETOOLONG; |
0dc49e9b SK |
558 | |
559 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
560 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
561 | "authencesn(%s,%s)", | |
562 | x->aalg ? x->aalg->alg_name : "digest_null", | |
563 | x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
564 | goto error; | |
565 | } else { | |
566 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
567 | "authenc(%s,%s)", | |
568 | x->aalg ? x->aalg->alg_name : "digest_null", | |
569 | x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
570 | goto error; | |
571 | } | |
38320c70 HX |
572 | |
573 | aead = crypto_alloc_aead(authenc_name, 0, 0); | |
574 | err = PTR_ERR(aead); | |
575 | if (IS_ERR(aead)) | |
576 | goto error; | |
577 | ||
578 | esp->aead = aead; | |
579 | ||
580 | keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + | |
581 | (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); | |
582 | err = -ENOMEM; | |
583 | key = kmalloc(keylen, GFP_KERNEL); | |
584 | if (!key) | |
585 | goto error; | |
586 | ||
587 | p = key; | |
588 | rta = (void *)p; | |
589 | rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; | |
590 | rta->rta_len = RTA_LENGTH(sizeof(*param)); | |
591 | param = RTA_DATA(rta); | |
592 | p += RTA_SPACE(sizeof(*param)); | |
593 | ||
1da177e4 LT |
594 | if (x->aalg) { |
595 | struct xfrm_algo_desc *aalg_desc; | |
596 | ||
38320c70 HX |
597 | memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); |
598 | p += (x->aalg->alg_key_len + 7) / 8; | |
1da177e4 LT |
599 | |
600 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); | |
601 | BUG_ON(!aalg_desc); | |
602 | ||
38320c70 | 603 | err = -EINVAL; |
1da177e4 | 604 | if (aalg_desc->uinfo.auth.icv_fullbits/8 != |
38320c70 | 605 | crypto_aead_authsize(aead)) { |
64ce2073 PM |
606 | NETDEBUG(KERN_INFO "ESP: %s digestsize %u != %hu\n", |
607 | x->aalg->alg_name, | |
38320c70 | 608 | crypto_aead_authsize(aead), |
64ce2073 | 609 | aalg_desc->uinfo.auth.icv_fullbits/8); |
38320c70 | 610 | goto free_key; |
1da177e4 LT |
611 | } |
612 | ||
38320c70 | 613 | err = crypto_aead_setauthsize( |
8f8a088c | 614 | aead, x->aalg->alg_trunc_len / 8); |
38320c70 HX |
615 | if (err) |
616 | goto free_key; | |
1da177e4 | 617 | } |
4b7137ff | 618 | |
38320c70 HX |
619 | param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); |
620 | memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); | |
621 | ||
622 | err = crypto_aead_setkey(aead, key, keylen); | |
623 | ||
624 | free_key: | |
625 | kfree(key); | |
626 | ||
1a6509d9 HX |
627 | error: |
628 | return err; | |
629 | } | |
630 | ||
631 | static int esp_init_state(struct xfrm_state *x) | |
632 | { | |
633 | struct esp_data *esp; | |
634 | struct crypto_aead *aead; | |
635 | u32 align; | |
636 | int err; | |
637 | ||
638 | esp = kzalloc(sizeof(*esp), GFP_KERNEL); | |
639 | if (esp == NULL) | |
640 | return -ENOMEM; | |
641 | ||
642 | x->data = esp; | |
643 | ||
644 | if (x->aead) | |
645 | err = esp_init_aead(x); | |
646 | else | |
647 | err = esp_init_authenc(x); | |
648 | ||
38320c70 | 649 | if (err) |
1da177e4 | 650 | goto error; |
38320c70 | 651 | |
1a6509d9 HX |
652 | aead = esp->aead; |
653 | ||
654 | esp->padlen = 0; | |
655 | ||
38320c70 HX |
656 | x->props.header_len = sizeof(struct ip_esp_hdr) + |
657 | crypto_aead_ivsize(aead); | |
7e49e6de | 658 | if (x->props.mode == XFRM_MODE_TUNNEL) |
1da177e4 | 659 | x->props.header_len += sizeof(struct iphdr); |
eb49e630 | 660 | else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6) |
ac758e3c | 661 | x->props.header_len += IPV4_BEET_PHMAXLEN; |
1da177e4 LT |
662 | if (x->encap) { |
663 | struct xfrm_encap_tmpl *encap = x->encap; | |
664 | ||
665 | switch (encap->encap_type) { | |
666 | default: | |
667 | goto error; | |
668 | case UDP_ENCAP_ESPINUDP: | |
669 | x->props.header_len += sizeof(struct udphdr); | |
670 | break; | |
671 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
672 | x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32); | |
673 | break; | |
674 | } | |
675 | } | |
38320c70 HX |
676 | |
677 | align = ALIGN(crypto_aead_blocksize(aead), 4); | |
678 | if (esp->padlen) | |
679 | align = max_t(u32, align, esp->padlen); | |
680 | x->props.trailer_len = align + 1 + crypto_aead_authsize(esp->aead); | |
1da177e4 LT |
681 | |
682 | error: | |
38320c70 | 683 | return err; |
1da177e4 LT |
684 | } |
685 | ||
533cb5b0 | 686 | static const struct xfrm_type esp_type = |
1da177e4 LT |
687 | { |
688 | .description = "ESP4", | |
689 | .owner = THIS_MODULE, | |
690 | .proto = IPPROTO_ESP, | |
436a0a40 | 691 | .flags = XFRM_TYPE_REPLAY_PROT, |
1da177e4 LT |
692 | .init_state = esp_init_state, |
693 | .destructor = esp_destroy, | |
c5c25238 | 694 | .get_mtu = esp4_get_mtu, |
1da177e4 | 695 | .input = esp_input, |
1da177e4 LT |
696 | .output = esp_output |
697 | }; | |
698 | ||
32613090 | 699 | static const struct net_protocol esp4_protocol = { |
1da177e4 LT |
700 | .handler = xfrm4_rcv, |
701 | .err_handler = esp4_err, | |
702 | .no_policy = 1, | |
4fb236ba | 703 | .netns_ok = 1, |
1da177e4 LT |
704 | }; |
705 | ||
706 | static int __init esp4_init(void) | |
707 | { | |
1da177e4 LT |
708 | if (xfrm_register_type(&esp_type, AF_INET) < 0) { |
709 | printk(KERN_INFO "ip esp init: can't add xfrm type\n"); | |
710 | return -EAGAIN; | |
711 | } | |
712 | if (inet_add_protocol(&esp4_protocol, IPPROTO_ESP) < 0) { | |
713 | printk(KERN_INFO "ip esp init: can't add protocol\n"); | |
714 | xfrm_unregister_type(&esp_type, AF_INET); | |
715 | return -EAGAIN; | |
716 | } | |
717 | return 0; | |
718 | } | |
719 | ||
720 | static void __exit esp4_fini(void) | |
721 | { | |
722 | if (inet_del_protocol(&esp4_protocol, IPPROTO_ESP) < 0) | |
723 | printk(KERN_INFO "ip esp close: can't remove protocol\n"); | |
724 | if (xfrm_unregister_type(&esp_type, AF_INET) < 0) | |
725 | printk(KERN_INFO "ip esp close: can't remove xfrm type\n"); | |
726 | } | |
727 | ||
728 | module_init(esp4_init); | |
729 | module_exit(esp4_fini); | |
730 | MODULE_LICENSE("GPL"); | |
d3d6dd3a | 731 | MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP); |