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 LT |
124 | struct esp_data *esp; |
125 | struct sk_buff *trailer; | |
38320c70 HX |
126 | void *tmp; |
127 | u8 *iv; | |
27a884dc | 128 | u8 *tail; |
1da177e4 LT |
129 | int blksize; |
130 | int clen; | |
131 | int alen; | |
d979e20f MW |
132 | int plen; |
133 | int tfclen; | |
1da177e4 | 134 | int nfrags; |
0dc49e9b SK |
135 | int assoclen; |
136 | int sglists; | |
137 | int seqhilen; | |
138 | __be32 *seqhi; | |
1da177e4 | 139 | |
7b277b1a | 140 | /* skb is pure payload to encrypt */ |
1da177e4 LT |
141 | |
142 | err = -ENOMEM; | |
143 | ||
1da177e4 | 144 | esp = x->data; |
38320c70 HX |
145 | aead = esp->aead; |
146 | alen = crypto_aead_authsize(aead); | |
147 | ||
d979e20f MW |
148 | tfclen = 0; |
149 | if (x->tfcpad) { | |
150 | struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); | |
151 | u32 padto; | |
152 | ||
153 | padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached)); | |
154 | if (skb->len < padto) | |
155 | tfclen = padto - skb->len; | |
156 | } | |
38320c70 | 157 | blksize = ALIGN(crypto_aead_blocksize(aead), 4); |
d979e20f | 158 | clen = ALIGN(skb->len + 2 + tfclen, blksize); |
38320c70 HX |
159 | if (esp->padlen) |
160 | clen = ALIGN(clen, esp->padlen); | |
d979e20f | 161 | plen = clen - skb->len - tfclen; |
38320c70 | 162 | |
d979e20f MW |
163 | err = skb_cow_data(skb, tfclen + plen + alen, &trailer); |
164 | if (err < 0) | |
38320c70 HX |
165 | goto error; |
166 | nfrags = err; | |
1da177e4 | 167 | |
0dc49e9b SK |
168 | assoclen = sizeof(*esph); |
169 | sglists = 1; | |
170 | seqhilen = 0; | |
171 | ||
172 | if (x->props.flags & XFRM_STATE_ESN) { | |
173 | sglists += 2; | |
174 | seqhilen += sizeof(__be32); | |
175 | assoclen += seqhilen; | |
176 | } | |
177 | ||
178 | tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); | |
38320c70 | 179 | if (!tmp) |
1da177e4 LT |
180 | goto error; |
181 | ||
0dc49e9b SK |
182 | seqhi = esp_tmp_seqhi(tmp); |
183 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 HX |
184 | req = esp_tmp_givreq(aead, iv); |
185 | asg = esp_givreq_sg(aead, req); | |
0dc49e9b | 186 | sg = asg + sglists; |
38320c70 | 187 | |
1da177e4 | 188 | /* Fill padding... */ |
27a884dc | 189 | tail = skb_tail_pointer(trailer); |
d979e20f MW |
190 | if (tfclen) { |
191 | memset(tail, 0, tfclen); | |
192 | tail += tfclen; | |
193 | } | |
1da177e4 LT |
194 | do { |
195 | int i; | |
d979e20f | 196 | for (i = 0; i < plen - 2; i++) |
27a884dc | 197 | tail[i] = i + 1; |
1da177e4 | 198 | } while (0); |
d979e20f MW |
199 | tail[plen - 2] = plen - 2; |
200 | tail[plen - 1] = *skb_mac_header(skb); | |
38320c70 | 201 | pskb_put(skb, trailer, clen - skb->len + alen); |
1da177e4 | 202 | |
7b277b1a | 203 | skb_push(skb, -skb_network_offset(skb)); |
87bdc48d | 204 | esph = ip_esp_hdr(skb); |
37fedd3a | 205 | *skb_mac_header(skb) = IPPROTO_ESP; |
1da177e4 LT |
206 | |
207 | /* this is non-NULL only with UDP Encapsulation */ | |
208 | if (x->encap) { | |
209 | struct xfrm_encap_tmpl *encap = x->encap; | |
210 | struct udphdr *uh; | |
d5a0a1e3 | 211 | __be32 *udpdata32; |
5e226e4d | 212 | __be16 sport, dport; |
38320c70 HX |
213 | int encap_type; |
214 | ||
215 | spin_lock_bh(&x->lock); | |
216 | sport = encap->encap_sport; | |
217 | dport = encap->encap_dport; | |
218 | encap_type = encap->encap_type; | |
219 | spin_unlock_bh(&x->lock); | |
1da177e4 LT |
220 | |
221 | uh = (struct udphdr *)esph; | |
38320c70 HX |
222 | uh->source = sport; |
223 | uh->dest = dport; | |
224 | uh->len = htons(skb->len - skb_transport_offset(skb)); | |
1da177e4 LT |
225 | uh->check = 0; |
226 | ||
38320c70 | 227 | switch (encap_type) { |
1da177e4 LT |
228 | default: |
229 | case UDP_ENCAP_ESPINUDP: | |
230 | esph = (struct ip_esp_hdr *)(uh + 1); | |
231 | break; | |
232 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
d5a0a1e3 | 233 | udpdata32 = (__be32 *)(uh + 1); |
1da177e4 LT |
234 | udpdata32[0] = udpdata32[1] = 0; |
235 | esph = (struct ip_esp_hdr *)(udpdata32 + 2); | |
236 | break; | |
237 | } | |
238 | ||
37fedd3a HX |
239 | *skb_mac_header(skb) = IPPROTO_UDP; |
240 | } | |
1da177e4 LT |
241 | |
242 | esph->spi = x->id.spi; | |
1ce3644a | 243 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); |
1da177e4 | 244 | |
38320c70 HX |
245 | sg_init_table(sg, nfrags); |
246 | skb_to_sgvec(skb, sg, | |
247 | esph->enc_data + crypto_aead_ivsize(aead) - skb->data, | |
248 | clen + alen); | |
0dc49e9b SK |
249 | |
250 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
251 | sg_init_table(asg, 3); | |
252 | sg_set_buf(asg, &esph->spi, sizeof(__be32)); | |
253 | *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); | |
254 | sg_set_buf(asg + 1, seqhi, seqhilen); | |
255 | sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); | |
256 | } else | |
257 | sg_init_one(asg, esph, sizeof(*esph)); | |
38320c70 HX |
258 | |
259 | aead_givcrypt_set_callback(req, 0, esp_output_done, skb); | |
260 | aead_givcrypt_set_crypt(req, sg, sg, clen, iv); | |
0dc49e9b | 261 | aead_givcrypt_set_assoc(req, asg, assoclen); |
b318e0e4 | 262 | aead_givcrypt_set_giv(req, esph->enc_data, |
1ce3644a | 263 | XFRM_SKB_CB(skb)->seq.output.low); |
38320c70 HX |
264 | |
265 | ESP_SKB_CB(skb)->tmp = tmp; | |
266 | err = crypto_aead_givencrypt(req); | |
267 | if (err == -EINPROGRESS) | |
268 | goto error; | |
1da177e4 | 269 | |
38320c70 HX |
270 | if (err == -EBUSY) |
271 | err = NET_XMIT_DROP; | |
1da177e4 | 272 | |
38320c70 | 273 | kfree(tmp); |
b7c6538c | 274 | |
1da177e4 LT |
275 | error: |
276 | return err; | |
277 | } | |
278 | ||
38320c70 | 279 | static int esp_input_done2(struct sk_buff *skb, int err) |
1da177e4 | 280 | { |
b71d1d42 | 281 | const struct iphdr *iph; |
38320c70 | 282 | struct xfrm_state *x = xfrm_input_state(skb); |
1da177e4 | 283 | struct esp_data *esp = x->data; |
38320c70 HX |
284 | struct crypto_aead *aead = esp->aead; |
285 | int alen = crypto_aead_authsize(aead); | |
286 | int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
287 | int elen = skb->len - hlen; | |
31a4ab93 | 288 | int ihl; |
4bf05ece | 289 | u8 nexthdr[2]; |
4bf05ece | 290 | int padlen; |
1da177e4 | 291 | |
38320c70 | 292 | kfree(ESP_SKB_CB(skb)->tmp); |
0ebea8ef | 293 | |
6b7326c8 | 294 | if (unlikely(err)) |
668dc8af | 295 | goto out; |
1da177e4 | 296 | |
4bf05ece HX |
297 | if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) |
298 | BUG(); | |
1da177e4 | 299 | |
668dc8af | 300 | err = -EINVAL; |
4bf05ece | 301 | padlen = nexthdr[0]; |
38320c70 | 302 | if (padlen + 2 + alen >= elen) |
4bf05ece | 303 | goto out; |
1da177e4 | 304 | |
e905a9ed | 305 | /* ... check padding bits here. Silly. :-) */ |
1da177e4 | 306 | |
eddc9ec5 | 307 | iph = ip_hdr(skb); |
31a4ab93 HX |
308 | ihl = iph->ihl * 4; |
309 | ||
752c1f4c HX |
310 | if (x->encap) { |
311 | struct xfrm_encap_tmpl *encap = x->encap; | |
d56f90a7 | 312 | struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); |
752c1f4c HX |
313 | |
314 | /* | |
315 | * 1) if the NAT-T peer's IP or port changed then | |
316 | * advertize the change to the keying daemon. | |
317 | * This is an inbound SA, so just compare | |
318 | * SRC ports. | |
319 | */ | |
320 | if (iph->saddr != x->props.saddr.a4 || | |
321 | uh->source != encap->encap_sport) { | |
322 | xfrm_address_t ipaddr; | |
323 | ||
324 | ipaddr.a4 = iph->saddr; | |
325 | km_new_mapping(x, &ipaddr, uh->source); | |
e905a9ed | 326 | |
752c1f4c HX |
327 | /* XXX: perhaps add an extra |
328 | * policy check here, to see | |
329 | * if we should allow or | |
330 | * reject a packet from a | |
331 | * different source | |
332 | * address/port. | |
333 | */ | |
1da177e4 | 334 | } |
e905a9ed | 335 | |
752c1f4c HX |
336 | /* |
337 | * 2) ignore UDP/TCP checksums in case | |
338 | * of NAT-T in Transport Mode, or | |
339 | * perform other post-processing fixes | |
340 | * as per draft-ietf-ipsec-udp-encaps-06, | |
341 | * section 3.1.2 | |
342 | */ | |
8bd17075 | 343 | if (x->props.mode == XFRM_MODE_TRANSPORT) |
752c1f4c | 344 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
1da177e4 LT |
345 | } |
346 | ||
4bf05ece | 347 | pskb_trim(skb, skb->len - alen - padlen - 2); |
38320c70 | 348 | __skb_pull(skb, hlen); |
967b05f6 | 349 | skb_set_transport_header(skb, -ihl); |
4bf05ece | 350 | |
38320c70 HX |
351 | err = nexthdr[1]; |
352 | ||
353 | /* RFC4303: Drop dummy packets without any error */ | |
354 | if (err == IPPROTO_NONE) | |
355 | err = -EINVAL; | |
356 | ||
357 | out: | |
358 | return err; | |
359 | } | |
360 | ||
361 | static void esp_input_done(struct crypto_async_request *base, int err) | |
362 | { | |
363 | struct sk_buff *skb = base->data; | |
364 | ||
365 | xfrm_input_resume(skb, esp_input_done2(skb, err)); | |
366 | } | |
367 | ||
368 | /* | |
369 | * Note: detecting truncated vs. non-truncated authentication data is very | |
370 | * expensive, so we only support truncated data, which is the recommended | |
371 | * and common case. | |
372 | */ | |
373 | static int esp_input(struct xfrm_state *x, struct sk_buff *skb) | |
374 | { | |
375 | struct ip_esp_hdr *esph; | |
376 | struct esp_data *esp = x->data; | |
377 | struct crypto_aead *aead = esp->aead; | |
378 | struct aead_request *req; | |
379 | struct sk_buff *trailer; | |
380 | int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead); | |
381 | int nfrags; | |
0dc49e9b SK |
382 | int assoclen; |
383 | int sglists; | |
384 | int seqhilen; | |
385 | __be32 *seqhi; | |
38320c70 HX |
386 | void *tmp; |
387 | u8 *iv; | |
388 | struct scatterlist *sg; | |
389 | struct scatterlist *asg; | |
390 | int err = -EINVAL; | |
391 | ||
920fc941 | 392 | if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) |
38320c70 HX |
393 | goto out; |
394 | ||
395 | if (elen <= 0) | |
396 | goto out; | |
397 | ||
398 | if ((err = skb_cow_data(skb, 0, &trailer)) < 0) | |
399 | goto out; | |
400 | nfrags = err; | |
401 | ||
0dc49e9b SK |
402 | assoclen = sizeof(*esph); |
403 | sglists = 1; | |
404 | seqhilen = 0; | |
405 | ||
406 | if (x->props.flags & XFRM_STATE_ESN) { | |
407 | sglists += 2; | |
408 | seqhilen += sizeof(__be32); | |
409 | assoclen += seqhilen; | |
410 | } | |
411 | ||
38320c70 | 412 | err = -ENOMEM; |
0dc49e9b | 413 | tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); |
38320c70 HX |
414 | if (!tmp) |
415 | goto out; | |
416 | ||
417 | ESP_SKB_CB(skb)->tmp = tmp; | |
0dc49e9b SK |
418 | seqhi = esp_tmp_seqhi(tmp); |
419 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 HX |
420 | req = esp_tmp_req(aead, iv); |
421 | asg = esp_req_sg(aead, req); | |
0dc49e9b | 422 | sg = asg + sglists; |
38320c70 HX |
423 | |
424 | skb->ip_summed = CHECKSUM_NONE; | |
425 | ||
426 | esph = (struct ip_esp_hdr *)skb->data; | |
427 | ||
428 | /* Get ivec. This can be wrong, check against another impls. */ | |
429 | iv = esph->enc_data; | |
430 | ||
431 | sg_init_table(sg, nfrags); | |
432 | skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen); | |
0dc49e9b SK |
433 | |
434 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
435 | sg_init_table(asg, 3); | |
436 | sg_set_buf(asg, &esph->spi, sizeof(__be32)); | |
437 | *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; | |
438 | sg_set_buf(asg + 1, seqhi, seqhilen); | |
439 | sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); | |
440 | } else | |
441 | sg_init_one(asg, esph, sizeof(*esph)); | |
38320c70 HX |
442 | |
443 | aead_request_set_callback(req, 0, esp_input_done, skb); | |
444 | aead_request_set_crypt(req, sg, sg, elen, iv); | |
0dc49e9b | 445 | aead_request_set_assoc(req, asg, assoclen); |
38320c70 HX |
446 | |
447 | err = crypto_aead_decrypt(req); | |
448 | if (err == -EINPROGRESS) | |
449 | goto out; | |
450 | ||
451 | err = esp_input_done2(skb, err); | |
1da177e4 LT |
452 | |
453 | out: | |
668dc8af | 454 | return err; |
1da177e4 LT |
455 | } |
456 | ||
c5c25238 | 457 | static u32 esp4_get_mtu(struct xfrm_state *x, int mtu) |
1da177e4 LT |
458 | { |
459 | struct esp_data *esp = x->data; | |
38320c70 HX |
460 | u32 blksize = ALIGN(crypto_aead_blocksize(esp->aead), 4); |
461 | u32 align = max_t(u32, blksize, esp->padlen); | |
c5c25238 PM |
462 | u32 rem; |
463 | ||
38320c70 | 464 | mtu -= x->props.header_len + crypto_aead_authsize(esp->aead); |
c5c25238 PM |
465 | rem = mtu & (align - 1); |
466 | mtu &= ~(align - 1); | |
0a69452c DB |
467 | |
468 | switch (x->props.mode) { | |
469 | case XFRM_MODE_TUNNEL: | |
0a69452c DB |
470 | break; |
471 | default: | |
472 | case XFRM_MODE_TRANSPORT: | |
473 | /* The worst case */ | |
c5c25238 PM |
474 | mtu -= blksize - 4; |
475 | mtu += min_t(u32, blksize - 4, rem); | |
0a69452c DB |
476 | break; |
477 | case XFRM_MODE_BEET: | |
e905a9ed | 478 | /* The worst case. */ |
c5c25238 | 479 | mtu += min_t(u32, IPV4_BEET_PHMAXLEN, rem); |
0a69452c | 480 | break; |
1da177e4 | 481 | } |
0a69452c | 482 | |
c5c25238 | 483 | return mtu - 2; |
1da177e4 LT |
484 | } |
485 | ||
486 | static void esp4_err(struct sk_buff *skb, u32 info) | |
487 | { | |
4fb236ba | 488 | struct net *net = dev_net(skb->dev); |
b71d1d42 | 489 | const struct iphdr *iph = (const struct iphdr *)skb->data; |
d9319100 | 490 | struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); |
1da177e4 LT |
491 | struct xfrm_state *x; |
492 | ||
88c7664f ACM |
493 | if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH || |
494 | icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) | |
1da177e4 LT |
495 | return; |
496 | ||
b71d1d42 ED |
497 | x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, |
498 | esph->spi, IPPROTO_ESP, AF_INET); | |
1da177e4 LT |
499 | if (!x) |
500 | return; | |
64ce2073 PM |
501 | NETDEBUG(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%08x\n", |
502 | ntohl(esph->spi), ntohl(iph->daddr)); | |
1da177e4 LT |
503 | xfrm_state_put(x); |
504 | } | |
505 | ||
506 | static void esp_destroy(struct xfrm_state *x) | |
507 | { | |
508 | struct esp_data *esp = x->data; | |
509 | ||
510 | if (!esp) | |
511 | return; | |
512 | ||
38320c70 | 513 | crypto_free_aead(esp->aead); |
1da177e4 LT |
514 | kfree(esp); |
515 | } | |
516 | ||
1a6509d9 | 517 | static int esp_init_aead(struct xfrm_state *x) |
1da177e4 | 518 | { |
1a6509d9 HX |
519 | struct esp_data *esp = x->data; |
520 | struct crypto_aead *aead; | |
521 | int err; | |
522 | ||
523 | aead = crypto_alloc_aead(x->aead->alg_name, 0, 0); | |
524 | err = PTR_ERR(aead); | |
525 | if (IS_ERR(aead)) | |
526 | goto error; | |
527 | ||
528 | esp->aead = aead; | |
529 | ||
530 | err = crypto_aead_setkey(aead, x->aead->alg_key, | |
531 | (x->aead->alg_key_len + 7) / 8); | |
532 | if (err) | |
533 | goto error; | |
534 | ||
535 | err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); | |
536 | if (err) | |
537 | goto error; | |
538 | ||
539 | error: | |
540 | return err; | |
541 | } | |
542 | ||
543 | static int esp_init_authenc(struct xfrm_state *x) | |
544 | { | |
545 | struct esp_data *esp = x->data; | |
38320c70 HX |
546 | struct crypto_aead *aead; |
547 | struct crypto_authenc_key_param *param; | |
548 | struct rtattr *rta; | |
549 | char *key; | |
550 | char *p; | |
551 | char authenc_name[CRYPTO_MAX_ALG_NAME]; | |
38320c70 HX |
552 | unsigned int keylen; |
553 | int err; | |
1da177e4 | 554 | |
1a6509d9 | 555 | err = -EINVAL; |
1da177e4 | 556 | if (x->ealg == NULL) |
1a6509d9 | 557 | goto error; |
38320c70 | 558 | |
1a6509d9 | 559 | err = -ENAMETOOLONG; |
0dc49e9b SK |
560 | |
561 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
562 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
563 | "authencesn(%s,%s)", | |
564 | x->aalg ? x->aalg->alg_name : "digest_null", | |
565 | x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
566 | goto error; | |
567 | } else { | |
568 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
569 | "authenc(%s,%s)", | |
570 | x->aalg ? x->aalg->alg_name : "digest_null", | |
571 | x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
572 | goto error; | |
573 | } | |
38320c70 HX |
574 | |
575 | aead = crypto_alloc_aead(authenc_name, 0, 0); | |
576 | err = PTR_ERR(aead); | |
577 | if (IS_ERR(aead)) | |
578 | goto error; | |
579 | ||
580 | esp->aead = aead; | |
581 | ||
582 | keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + | |
583 | (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); | |
584 | err = -ENOMEM; | |
585 | key = kmalloc(keylen, GFP_KERNEL); | |
586 | if (!key) | |
587 | goto error; | |
588 | ||
589 | p = key; | |
590 | rta = (void *)p; | |
591 | rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; | |
592 | rta->rta_len = RTA_LENGTH(sizeof(*param)); | |
593 | param = RTA_DATA(rta); | |
594 | p += RTA_SPACE(sizeof(*param)); | |
595 | ||
1da177e4 LT |
596 | if (x->aalg) { |
597 | struct xfrm_algo_desc *aalg_desc; | |
598 | ||
38320c70 HX |
599 | memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); |
600 | p += (x->aalg->alg_key_len + 7) / 8; | |
1da177e4 LT |
601 | |
602 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); | |
603 | BUG_ON(!aalg_desc); | |
604 | ||
38320c70 | 605 | err = -EINVAL; |
1da177e4 | 606 | if (aalg_desc->uinfo.auth.icv_fullbits/8 != |
38320c70 | 607 | crypto_aead_authsize(aead)) { |
64ce2073 PM |
608 | NETDEBUG(KERN_INFO "ESP: %s digestsize %u != %hu\n", |
609 | x->aalg->alg_name, | |
38320c70 | 610 | crypto_aead_authsize(aead), |
64ce2073 | 611 | aalg_desc->uinfo.auth.icv_fullbits/8); |
38320c70 | 612 | goto free_key; |
1da177e4 LT |
613 | } |
614 | ||
38320c70 | 615 | err = crypto_aead_setauthsize( |
8f8a088c | 616 | aead, x->aalg->alg_trunc_len / 8); |
38320c70 HX |
617 | if (err) |
618 | goto free_key; | |
1da177e4 | 619 | } |
4b7137ff | 620 | |
38320c70 HX |
621 | param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); |
622 | memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); | |
623 | ||
624 | err = crypto_aead_setkey(aead, key, keylen); | |
625 | ||
626 | free_key: | |
627 | kfree(key); | |
628 | ||
1a6509d9 HX |
629 | error: |
630 | return err; | |
631 | } | |
632 | ||
633 | static int esp_init_state(struct xfrm_state *x) | |
634 | { | |
635 | struct esp_data *esp; | |
636 | struct crypto_aead *aead; | |
637 | u32 align; | |
638 | int err; | |
639 | ||
640 | esp = kzalloc(sizeof(*esp), GFP_KERNEL); | |
641 | if (esp == NULL) | |
642 | return -ENOMEM; | |
643 | ||
644 | x->data = esp; | |
645 | ||
646 | if (x->aead) | |
647 | err = esp_init_aead(x); | |
648 | else | |
649 | err = esp_init_authenc(x); | |
650 | ||
38320c70 | 651 | if (err) |
1da177e4 | 652 | goto error; |
38320c70 | 653 | |
1a6509d9 HX |
654 | aead = esp->aead; |
655 | ||
656 | esp->padlen = 0; | |
657 | ||
38320c70 HX |
658 | x->props.header_len = sizeof(struct ip_esp_hdr) + |
659 | crypto_aead_ivsize(aead); | |
7e49e6de | 660 | if (x->props.mode == XFRM_MODE_TUNNEL) |
1da177e4 | 661 | x->props.header_len += sizeof(struct iphdr); |
eb49e630 | 662 | else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6) |
ac758e3c | 663 | x->props.header_len += IPV4_BEET_PHMAXLEN; |
1da177e4 LT |
664 | if (x->encap) { |
665 | struct xfrm_encap_tmpl *encap = x->encap; | |
666 | ||
667 | switch (encap->encap_type) { | |
668 | default: | |
669 | goto error; | |
670 | case UDP_ENCAP_ESPINUDP: | |
671 | x->props.header_len += sizeof(struct udphdr); | |
672 | break; | |
673 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
674 | x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32); | |
675 | break; | |
676 | } | |
677 | } | |
38320c70 HX |
678 | |
679 | align = ALIGN(crypto_aead_blocksize(aead), 4); | |
680 | if (esp->padlen) | |
681 | align = max_t(u32, align, esp->padlen); | |
682 | x->props.trailer_len = align + 1 + crypto_aead_authsize(esp->aead); | |
1da177e4 LT |
683 | |
684 | error: | |
38320c70 | 685 | return err; |
1da177e4 LT |
686 | } |
687 | ||
533cb5b0 | 688 | static const struct xfrm_type esp_type = |
1da177e4 LT |
689 | { |
690 | .description = "ESP4", | |
691 | .owner = THIS_MODULE, | |
692 | .proto = IPPROTO_ESP, | |
436a0a40 | 693 | .flags = XFRM_TYPE_REPLAY_PROT, |
1da177e4 LT |
694 | .init_state = esp_init_state, |
695 | .destructor = esp_destroy, | |
c5c25238 | 696 | .get_mtu = esp4_get_mtu, |
1da177e4 | 697 | .input = esp_input, |
1da177e4 LT |
698 | .output = esp_output |
699 | }; | |
700 | ||
32613090 | 701 | static const struct net_protocol esp4_protocol = { |
1da177e4 LT |
702 | .handler = xfrm4_rcv, |
703 | .err_handler = esp4_err, | |
704 | .no_policy = 1, | |
4fb236ba | 705 | .netns_ok = 1, |
1da177e4 LT |
706 | }; |
707 | ||
708 | static int __init esp4_init(void) | |
709 | { | |
1da177e4 | 710 | if (xfrm_register_type(&esp_type, AF_INET) < 0) { |
058bd4d2 | 711 | pr_info("%s: can't add xfrm type\n", __func__); |
1da177e4 LT |
712 | return -EAGAIN; |
713 | } | |
714 | if (inet_add_protocol(&esp4_protocol, IPPROTO_ESP) < 0) { | |
058bd4d2 | 715 | pr_info("%s: can't add protocol\n", __func__); |
1da177e4 LT |
716 | xfrm_unregister_type(&esp_type, AF_INET); |
717 | return -EAGAIN; | |
718 | } | |
719 | return 0; | |
720 | } | |
721 | ||
722 | static void __exit esp4_fini(void) | |
723 | { | |
724 | if (inet_del_protocol(&esp4_protocol, IPPROTO_ESP) < 0) | |
058bd4d2 | 725 | pr_info("%s: can't remove protocol\n", __func__); |
1da177e4 | 726 | if (xfrm_unregister_type(&esp_type, AF_INET) < 0) |
058bd4d2 | 727 | pr_info("%s: can't remove xfrm type\n", __func__); |
1da177e4 LT |
728 | } |
729 | ||
730 | module_init(esp4_init); | |
731 | module_exit(esp4_fini); | |
732 | MODULE_LICENSE("GPL"); | |
d3d6dd3a | 733 | MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP); |