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Commit | Line | Data |
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1ccea77e | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * Copyright (C)2002 USAGI/WIDE Project | |
1ab1457c | 4 | * |
1da177e4 LT |
5 | * Authors |
6 | * | |
1ab1457c | 7 | * Mitsuru KANDA @USAGI : IPv6 Support |
67ba4152 IM |
8 | * Kazunori MIYAZAWA @USAGI : |
9 | * Kunihiro Ishiguro <kunihiro@ipinfusion.com> | |
1ab1457c | 10 | * |
67ba4152 | 11 | * This file is derived from net/ipv4/esp.c |
1da177e4 LT |
12 | */ |
13 | ||
f3213831 JP |
14 | #define pr_fmt(fmt) "IPv6: " fmt |
15 | ||
38320c70 HX |
16 | #include <crypto/aead.h> |
17 | #include <crypto/authenc.h> | |
6b7326c8 | 18 | #include <linux/err.h> |
1da177e4 LT |
19 | #include <linux/module.h> |
20 | #include <net/ip.h> | |
21 | #include <net/xfrm.h> | |
22 | #include <net/esp.h> | |
72998d8c | 23 | #include <linux/scatterlist.h> |
a02a6422 | 24 | #include <linux/kernel.h> |
1da177e4 LT |
25 | #include <linux/pfkeyv2.h> |
26 | #include <linux/random.h> | |
38320c70 | 27 | #include <linux/slab.h> |
b7c6538c | 28 | #include <linux/spinlock.h> |
81aded24 | 29 | #include <net/ip6_route.h> |
1da177e4 LT |
30 | #include <net/icmp.h> |
31 | #include <net/ipv6.h> | |
14c85021 | 32 | #include <net/protocol.h> |
1da177e4 LT |
33 | #include <linux/icmpv6.h> |
34 | ||
03e2a30f SK |
35 | #include <linux/highmem.h> |
36 | ||
38320c70 HX |
37 | struct esp_skb_cb { |
38 | struct xfrm_skb_cb xfrm; | |
39 | void *tmp; | |
40 | }; | |
41 | ||
42 | #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) | |
43 | ||
44 | /* | |
45 | * Allocate an AEAD request structure with extra space for SG and IV. | |
46 | * | |
d212a4c2 SK |
47 | * For alignment considerations the upper 32 bits of the sequence number are |
48 | * placed at the front, if present. Followed by the IV, the request and finally | |
49 | * the SG list. | |
38320c70 HX |
50 | * |
51 | * TODO: Use spare space in skb for this where possible. | |
52 | */ | |
d212a4c2 | 53 | static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqihlen) |
38320c70 HX |
54 | { |
55 | unsigned int len; | |
56 | ||
d212a4c2 SK |
57 | len = seqihlen; |
58 | ||
59 | len += crypto_aead_ivsize(aead); | |
60 | ||
38320c70 HX |
61 | if (len) { |
62 | len += crypto_aead_alignmask(aead) & | |
63 | ~(crypto_tfm_ctx_alignment() - 1); | |
64 | len = ALIGN(len, crypto_tfm_ctx_alignment()); | |
65 | } | |
66 | ||
000ae7b2 | 67 | len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); |
38320c70 HX |
68 | len = ALIGN(len, __alignof__(struct scatterlist)); |
69 | ||
70 | len += sizeof(struct scatterlist) * nfrags; | |
71 | ||
72 | return kmalloc(len, GFP_ATOMIC); | |
73 | } | |
74 | ||
d212a4c2 SK |
75 | static inline __be32 *esp_tmp_seqhi(void *tmp) |
76 | { | |
77 | return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); | |
78 | } | |
79 | ||
80 | static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) | |
38320c70 HX |
81 | { |
82 | return crypto_aead_ivsize(aead) ? | |
d212a4c2 SK |
83 | PTR_ALIGN((u8 *)tmp + seqhilen, |
84 | crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; | |
38320c70 HX |
85 | } |
86 | ||
38320c70 HX |
87 | static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) |
88 | { | |
89 | struct aead_request *req; | |
90 | ||
91 | req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), | |
92 | crypto_tfm_ctx_alignment()); | |
93 | aead_request_set_tfm(req, aead); | |
94 | return req; | |
95 | } | |
96 | ||
97 | static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, | |
98 | struct aead_request *req) | |
99 | { | |
100 | return (void *)ALIGN((unsigned long)(req + 1) + | |
101 | crypto_aead_reqsize(aead), | |
102 | __alignof__(struct scatterlist)); | |
103 | } | |
104 | ||
03e2a30f SK |
105 | static void esp_ssg_unref(struct xfrm_state *x, void *tmp) |
106 | { | |
03e2a30f SK |
107 | struct crypto_aead *aead = x->data; |
108 | int seqhilen = 0; | |
109 | u8 *iv; | |
110 | struct aead_request *req; | |
111 | struct scatterlist *sg; | |
112 | ||
113 | if (x->props.flags & XFRM_STATE_ESN) | |
114 | seqhilen += sizeof(__be32); | |
115 | ||
03e2a30f SK |
116 | iv = esp_tmp_iv(aead, tmp, seqhilen); |
117 | req = esp_tmp_req(aead, iv); | |
118 | ||
119 | /* Unref skb_frag_pages in the src scatterlist if necessary. | |
120 | * Skip the first sg which comes from skb->data. | |
121 | */ | |
122 | if (req->src != req->dst) | |
123 | for (sg = sg_next(req->src); sg; sg = sg_next(sg)) | |
124 | put_page(sg_page(sg)); | |
125 | } | |
126 | ||
38320c70 HX |
127 | static void esp_output_done(struct crypto_async_request *base, int err) |
128 | { | |
129 | struct sk_buff *skb = base->data; | |
f53c7239 | 130 | struct xfrm_offload *xo = xfrm_offload(skb); |
03e2a30f | 131 | void *tmp; |
f53c7239 SK |
132 | struct xfrm_state *x; |
133 | ||
2294be0f FW |
134 | if (xo && (xo->flags & XFRM_DEV_RESUME)) { |
135 | struct sec_path *sp = skb_sec_path(skb); | |
136 | ||
137 | x = sp->xvec[sp->len - 1]; | |
138 | } else { | |
f53c7239 | 139 | x = skb_dst(skb)->xfrm; |
2294be0f | 140 | } |
38320c70 | 141 | |
03e2a30f SK |
142 | tmp = ESP_SKB_CB(skb)->tmp; |
143 | esp_ssg_unref(x, tmp); | |
144 | kfree(tmp); | |
f53c7239 SK |
145 | |
146 | if (xo && (xo->flags & XFRM_DEV_RESUME)) { | |
147 | if (err) { | |
148 | XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR); | |
149 | kfree_skb(skb); | |
150 | return; | |
151 | } | |
152 | ||
153 | skb_push(skb, skb->data - skb_mac_header(skb)); | |
154 | secpath_reset(skb); | |
155 | xfrm_dev_resume(skb); | |
156 | } else { | |
157 | xfrm_output_resume(skb, err); | |
158 | } | |
38320c70 HX |
159 | } |
160 | ||
000ae7b2 HX |
161 | /* Move ESP header back into place. */ |
162 | static void esp_restore_header(struct sk_buff *skb, unsigned int offset) | |
163 | { | |
164 | struct ip_esp_hdr *esph = (void *)(skb->data + offset); | |
165 | void *tmp = ESP_SKB_CB(skb)->tmp; | |
166 | __be32 *seqhi = esp_tmp_seqhi(tmp); | |
167 | ||
168 | esph->seq_no = esph->spi; | |
169 | esph->spi = *seqhi; | |
170 | } | |
171 | ||
172 | static void esp_output_restore_header(struct sk_buff *skb) | |
173 | { | |
174 | esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); | |
175 | } | |
176 | ||
03e2a30f | 177 | static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb, |
383d0350 | 178 | struct xfrm_state *x, |
03e2a30f SK |
179 | struct ip_esp_hdr *esph, |
180 | __be32 *seqhi) | |
181 | { | |
03e2a30f SK |
182 | /* For ESN we move the header forward by 4 bytes to |
183 | * accomodate the high bits. We will move it back after | |
184 | * encryption. | |
185 | */ | |
186 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
7862b405 SK |
187 | struct xfrm_offload *xo = xfrm_offload(skb); |
188 | ||
03e2a30f SK |
189 | esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); |
190 | *seqhi = esph->spi; | |
7862b405 SK |
191 | if (xo) |
192 | esph->seq_no = htonl(xo->seq.hi); | |
193 | else | |
194 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); | |
03e2a30f SK |
195 | } |
196 | ||
197 | esph->spi = x->id.spi; | |
198 | ||
199 | return esph; | |
200 | } | |
201 | ||
000ae7b2 HX |
202 | static void esp_output_done_esn(struct crypto_async_request *base, int err) |
203 | { | |
204 | struct sk_buff *skb = base->data; | |
205 | ||
206 | esp_output_restore_header(skb); | |
207 | esp_output_done(base, err); | |
208 | } | |
209 | ||
eb758c88 SK |
210 | static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) |
211 | { | |
212 | /* Fill padding... */ | |
213 | if (tfclen) { | |
214 | memset(tail, 0, tfclen); | |
215 | tail += tfclen; | |
216 | } | |
217 | do { | |
218 | int i; | |
219 | for (i = 0; i < plen - 2; i++) | |
220 | tail[i] = i + 1; | |
221 | } while (0); | |
222 | tail[plen - 2] = plen - 2; | |
223 | tail[plen - 1] = proto; | |
224 | } | |
225 | ||
383d0350 | 226 | int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) |
1da177e4 | 227 | { |
27a884dc | 228 | u8 *tail; |
03e2a30f | 229 | u8 *vaddr; |
383d0350 SK |
230 | int nfrags; |
231 | struct page *page; | |
383d0350 SK |
232 | struct sk_buff *trailer; |
233 | int tailen = esp->tailen; | |
d212a4c2 | 234 | |
03e2a30f | 235 | if (!skb_cloned(skb)) { |
54ffd790 | 236 | if (tailen <= skb_tailroom(skb)) { |
03e2a30f SK |
237 | nfrags = 1; |
238 | trailer = skb; | |
239 | tail = skb_tail_pointer(trailer); | |
240 | ||
241 | goto skip_cow; | |
242 | } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) | |
243 | && !skb_has_frag_list(skb)) { | |
244 | int allocsize; | |
245 | struct sock *sk = skb->sk; | |
246 | struct page_frag *pfrag = &x->xfrag; | |
247 | ||
383d0350 SK |
248 | esp->inplace = false; |
249 | ||
03e2a30f SK |
250 | allocsize = ALIGN(tailen, L1_CACHE_BYTES); |
251 | ||
252 | spin_lock_bh(&x->lock); | |
253 | ||
254 | if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { | |
255 | spin_unlock_bh(&x->lock); | |
256 | goto cow; | |
257 | } | |
258 | ||
259 | page = pfrag->page; | |
260 | get_page(page); | |
261 | ||
262 | vaddr = kmap_atomic(page); | |
263 | ||
264 | tail = vaddr + pfrag->offset; | |
265 | ||
383d0350 | 266 | esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); |
03e2a30f SK |
267 | |
268 | kunmap_atomic(vaddr); | |
269 | ||
270 | nfrags = skb_shinfo(skb)->nr_frags; | |
271 | ||
272 | __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, | |
273 | tailen); | |
274 | skb_shinfo(skb)->nr_frags = ++nfrags; | |
275 | ||
276 | pfrag->offset = pfrag->offset + allocsize; | |
36ff0dd3 SK |
277 | |
278 | spin_unlock_bh(&x->lock); | |
279 | ||
03e2a30f SK |
280 | nfrags++; |
281 | ||
282 | skb->len += tailen; | |
283 | skb->data_len += tailen; | |
284 | skb->truesize += tailen; | |
09db5124 | 285 | if (sk && sk_fullsock(sk)) |
14afee4b | 286 | refcount_add(tailen, &sk->sk_wmem_alloc); |
03e2a30f | 287 | |
383d0350 | 288 | goto out; |
03e2a30f | 289 | } |
48f125ce | 290 | } |
38320c70 | 291 | |
03e2a30f | 292 | cow: |
383d0350 SK |
293 | nfrags = skb_cow_data(skb, tailen, &trailer); |
294 | if (nfrags < 0) | |
295 | goto out; | |
27a884dc | 296 | tail = skb_tail_pointer(trailer); |
03e2a30f SK |
297 | |
298 | skip_cow: | |
383d0350 SK |
299 | esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); |
300 | pskb_put(skb, trailer, tailen); | |
1da177e4 | 301 | |
383d0350 SK |
302 | out: |
303 | return nfrags; | |
304 | } | |
305 | EXPORT_SYMBOL_GPL(esp6_output_head); | |
1da177e4 | 306 | |
383d0350 SK |
307 | int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) |
308 | { | |
309 | u8 *iv; | |
310 | int alen; | |
311 | void *tmp; | |
312 | int ivlen; | |
313 | int assoclen; | |
314 | int seqhilen; | |
315 | __be32 *seqhi; | |
316 | struct page *page; | |
317 | struct ip_esp_hdr *esph; | |
318 | struct aead_request *req; | |
319 | struct crypto_aead *aead; | |
320 | struct scatterlist *sg, *dsg; | |
321 | int err = -ENOMEM; | |
322 | ||
323 | assoclen = sizeof(struct ip_esp_hdr); | |
324 | seqhilen = 0; | |
325 | ||
326 | if (x->props.flags & XFRM_STATE_ESN) { | |
327 | seqhilen += sizeof(__be32); | |
328 | assoclen += sizeof(__be32); | |
329 | } | |
1da177e4 | 330 | |
383d0350 SK |
331 | aead = x->data; |
332 | alen = crypto_aead_authsize(aead); | |
333 | ivlen = crypto_aead_ivsize(aead); | |
334 | ||
335 | tmp = esp_alloc_tmp(aead, esp->nfrags + 2, seqhilen); | |
e892d2d4 | 336 | if (!tmp) |
03e2a30f | 337 | goto error; |
000ae7b2 | 338 | |
03e2a30f SK |
339 | seqhi = esp_tmp_seqhi(tmp); |
340 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
341 | req = esp_tmp_req(aead, iv); | |
342 | sg = esp_req_sg(aead, req); | |
03e2a30f | 343 | |
383d0350 SK |
344 | if (esp->inplace) |
345 | dsg = sg; | |
346 | else | |
347 | dsg = &sg[esp->nfrags]; | |
348 | ||
349 | esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi); | |
000ae7b2 | 350 | |
383d0350 | 351 | sg_init_table(sg, esp->nfrags); |
3f297707 JD |
352 | err = skb_to_sgvec(skb, sg, |
353 | (unsigned char *)esph - skb->data, | |
354 | assoclen + ivlen + esp->clen + alen); | |
355 | if (unlikely(err < 0)) | |
e6194923 | 356 | goto error_free; |
383d0350 SK |
357 | |
358 | if (!esp->inplace) { | |
359 | int allocsize; | |
360 | struct page_frag *pfrag = &x->xfrag; | |
361 | ||
362 | allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); | |
363 | ||
364 | spin_lock_bh(&x->lock); | |
365 | if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { | |
366 | spin_unlock_bh(&x->lock); | |
e6194923 | 367 | goto error_free; |
383d0350 SK |
368 | } |
369 | ||
370 | skb_shinfo(skb)->nr_frags = 1; | |
371 | ||
372 | page = pfrag->page; | |
373 | get_page(page); | |
374 | /* replace page frags in skb with new page */ | |
375 | __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); | |
376 | pfrag->offset = pfrag->offset + allocsize; | |
377 | spin_unlock_bh(&x->lock); | |
378 | ||
379 | sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); | |
3f297707 JD |
380 | err = skb_to_sgvec(skb, dsg, |
381 | (unsigned char *)esph - skb->data, | |
382 | assoclen + ivlen + esp->clen + alen); | |
383 | if (unlikely(err < 0)) | |
e6194923 | 384 | goto error_free; |
383d0350 | 385 | } |
d212a4c2 | 386 | |
03e2a30f SK |
387 | if ((x->props.flags & XFRM_STATE_ESN)) |
388 | aead_request_set_callback(req, 0, esp_output_done_esn, skb); | |
389 | else | |
390 | aead_request_set_callback(req, 0, esp_output_done, skb); | |
391 | ||
383d0350 | 392 | aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv); |
000ae7b2 HX |
393 | aead_request_set_ad(req, assoclen); |
394 | ||
000ae7b2 | 395 | memset(iv, 0, ivlen); |
383d0350 | 396 | memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8), |
000ae7b2 | 397 | min(ivlen, 8)); |
1da177e4 | 398 | |
38320c70 | 399 | ESP_SKB_CB(skb)->tmp = tmp; |
000ae7b2 HX |
400 | err = crypto_aead_encrypt(req); |
401 | ||
402 | switch (err) { | |
403 | case -EINPROGRESS: | |
38320c70 | 404 | goto error; |
1da177e4 | 405 | |
068c2e70 | 406 | case -ENOSPC: |
38320c70 | 407 | err = NET_XMIT_DROP; |
000ae7b2 HX |
408 | break; |
409 | ||
410 | case 0: | |
411 | if ((x->props.flags & XFRM_STATE_ESN)) | |
412 | esp_output_restore_header(skb); | |
413 | } | |
38320c70 | 414 | |
03e2a30f SK |
415 | if (sg != dsg) |
416 | esp_ssg_unref(x, tmp); | |
38320c70 | 417 | |
e6194923 SK |
418 | error_free: |
419 | kfree(tmp); | |
38320c70 HX |
420 | error: |
421 | return err; | |
422 | } | |
383d0350 SK |
423 | EXPORT_SYMBOL_GPL(esp6_output_tail); |
424 | ||
425 | static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) | |
426 | { | |
427 | int alen; | |
428 | int blksize; | |
429 | struct ip_esp_hdr *esph; | |
430 | struct crypto_aead *aead; | |
431 | struct esp_info esp; | |
432 | ||
433 | esp.inplace = true; | |
434 | ||
435 | esp.proto = *skb_mac_header(skb); | |
436 | *skb_mac_header(skb) = IPPROTO_ESP; | |
437 | ||
438 | /* skb is pure payload to encrypt */ | |
439 | ||
440 | aead = x->data; | |
441 | alen = crypto_aead_authsize(aead); | |
442 | ||
443 | esp.tfclen = 0; | |
444 | if (x->tfcpad) { | |
445 | struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); | |
446 | u32 padto; | |
447 | ||
c7b37c76 | 448 | padto = min(x->tfcpad, xfrm_state_mtu(x, dst->child_mtu_cached)); |
383d0350 SK |
449 | if (skb->len < padto) |
450 | esp.tfclen = padto - skb->len; | |
451 | } | |
452 | blksize = ALIGN(crypto_aead_blocksize(aead), 4); | |
453 | esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); | |
454 | esp.plen = esp.clen - skb->len - esp.tfclen; | |
455 | esp.tailen = esp.tfclen + esp.plen + alen; | |
456 | ||
457 | esp.nfrags = esp6_output_head(x, skb, &esp); | |
458 | if (esp.nfrags < 0) | |
459 | return esp.nfrags; | |
460 | ||
461 | esph = ip_esp_hdr(skb); | |
462 | esph->spi = x->id.spi; | |
463 | ||
464 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); | |
465 | esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + | |
466 | ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); | |
467 | ||
468 | skb_push(skb, -skb_network_offset(skb)); | |
469 | ||
470 | return esp6_output_tail(x, skb, &esp); | |
471 | } | |
38320c70 | 472 | |
47ebcc0b | 473 | static inline int esp_remove_trailer(struct sk_buff *skb) |
38320c70 HX |
474 | { |
475 | struct xfrm_state *x = xfrm_input_state(skb); | |
d77e38e6 | 476 | struct xfrm_offload *xo = xfrm_offload(skb); |
1c5ad13f | 477 | struct crypto_aead *aead = x->data; |
47ebcc0b | 478 | int alen, hlen, elen; |
e51a6472 IT |
479 | int padlen, trimlen; |
480 | __wsum csumdiff; | |
38320c70 | 481 | u8 nexthdr[2]; |
47ebcc0b | 482 | int ret; |
38320c70 | 483 | |
47ebcc0b YK |
484 | alen = crypto_aead_authsize(aead); |
485 | hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
486 | elen = skb->len - hlen; | |
1da177e4 | 487 | |
47ebcc0b YK |
488 | if (xo && (xo->flags & XFRM_ESP_NO_TRAILER)) { |
489 | ret = xo->proto; | |
38320c70 | 490 | goto out; |
47ebcc0b | 491 | } |
6b7326c8 | 492 | |
eee12df5 GS |
493 | ret = skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2); |
494 | BUG_ON(ret); | |
1da177e4 | 495 | |
47ebcc0b | 496 | ret = -EINVAL; |
38320c70 HX |
497 | padlen = nexthdr[0]; |
498 | if (padlen + 2 + alen >= elen) { | |
ba7a46f1 JP |
499 | net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", |
500 | padlen + 2, elen - alen); | |
38320c70 | 501 | goto out; |
1da177e4 LT |
502 | } |
503 | ||
e51a6472 IT |
504 | trimlen = alen + padlen + 2; |
505 | if (skb->ip_summed == CHECKSUM_COMPLETE) { | |
506 | csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0); | |
507 | skb->csum = csum_block_sub(skb->csum, csumdiff, | |
508 | skb->len - trimlen); | |
509 | } | |
510 | pskb_trim(skb, skb->len - trimlen); | |
511 | ||
47ebcc0b YK |
512 | ret = nexthdr[1]; |
513 | ||
514 | out: | |
515 | return ret; | |
516 | } | |
517 | ||
518 | int esp6_input_done2(struct sk_buff *skb, int err) | |
519 | { | |
520 | struct xfrm_state *x = xfrm_input_state(skb); | |
521 | struct xfrm_offload *xo = xfrm_offload(skb); | |
522 | struct crypto_aead *aead = x->data; | |
523 | int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); | |
524 | int hdr_len = skb_network_header_len(skb); | |
525 | ||
526 | if (!xo || (xo && !(xo->flags & CRYPTO_DONE))) | |
527 | kfree(ESP_SKB_CB(skb)->tmp); | |
528 | ||
529 | if (unlikely(err)) | |
530 | goto out; | |
531 | ||
532 | err = esp_remove_trailer(skb); | |
533 | if (unlikely(err < 0)) | |
534 | goto out; | |
535 | ||
536 | skb_postpull_rcsum(skb, skb_network_header(skb), | |
537 | skb_network_header_len(skb)); | |
e51a6472 | 538 | skb_pull_rcsum(skb, hlen); |
a9403f8a LR |
539 | if (x->props.mode == XFRM_MODE_TUNNEL) |
540 | skb_reset_transport_header(skb); | |
541 | else | |
542 | skb_set_transport_header(skb, -hdr_len); | |
38320c70 | 543 | |
38320c70 HX |
544 | /* RFC4303: Drop dummy packets without any error */ |
545 | if (err == IPPROTO_NONE) | |
546 | err = -EINVAL; | |
547 | ||
548 | out: | |
1da177e4 LT |
549 | return err; |
550 | } | |
383d0350 | 551 | EXPORT_SYMBOL_GPL(esp6_input_done2); |
1da177e4 | 552 | |
38320c70 HX |
553 | static void esp_input_done(struct crypto_async_request *base, int err) |
554 | { | |
555 | struct sk_buff *skb = base->data; | |
556 | ||
f1fbed0e | 557 | xfrm_input_resume(skb, esp6_input_done2(skb, err)); |
38320c70 HX |
558 | } |
559 | ||
000ae7b2 HX |
560 | static void esp_input_restore_header(struct sk_buff *skb) |
561 | { | |
562 | esp_restore_header(skb, 0); | |
563 | __skb_pull(skb, 4); | |
564 | } | |
565 | ||
03e2a30f SK |
566 | static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) |
567 | { | |
568 | struct xfrm_state *x = xfrm_input_state(skb); | |
03e2a30f SK |
569 | |
570 | /* For ESN we move the header forward by 4 bytes to | |
571 | * accomodate the high bits. We will move it back after | |
572 | * decryption. | |
573 | */ | |
574 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
d3cc547d CIK |
575 | struct ip_esp_hdr *esph = skb_push(skb, 4); |
576 | ||
03e2a30f SK |
577 | *seqhi = esph->spi; |
578 | esph->spi = esph->seq_no; | |
579 | esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; | |
580 | } | |
581 | } | |
582 | ||
000ae7b2 HX |
583 | static void esp_input_done_esn(struct crypto_async_request *base, int err) |
584 | { | |
585 | struct sk_buff *skb = base->data; | |
586 | ||
587 | esp_input_restore_header(skb); | |
588 | esp_input_done(base, err); | |
589 | } | |
590 | ||
e695633e | 591 | static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) |
1da177e4 | 592 | { |
1c5ad13f | 593 | struct crypto_aead *aead = x->data; |
38320c70 | 594 | struct aead_request *req; |
1da177e4 | 595 | struct sk_buff *trailer; |
000ae7b2 | 596 | int ivlen = crypto_aead_ivsize(aead); |
0c05f983 | 597 | int elen = skb->len - sizeof(struct ip_esp_hdr) - ivlen; |
1da177e4 | 598 | int nfrags; |
d212a4c2 | 599 | int assoclen; |
d212a4c2 | 600 | int seqhilen; |
1da177e4 | 601 | int ret = 0; |
38320c70 | 602 | void *tmp; |
d212a4c2 | 603 | __be32 *seqhi; |
38320c70 HX |
604 | u8 *iv; |
605 | struct scatterlist *sg; | |
1da177e4 | 606 | |
0c05f983 | 607 | if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + ivlen)) { |
1da177e4 | 608 | ret = -EINVAL; |
31a4ab93 | 609 | goto out; |
1da177e4 LT |
610 | } |
611 | ||
38320c70 | 612 | if (elen <= 0) { |
1da177e4 | 613 | ret = -EINVAL; |
31a4ab93 | 614 | goto out; |
1da177e4 | 615 | } |
1da177e4 | 616 | |
0c05f983 | 617 | assoclen = sizeof(struct ip_esp_hdr); |
d212a4c2 SK |
618 | seqhilen = 0; |
619 | ||
620 | if (x->props.flags & XFRM_STATE_ESN) { | |
d212a4c2 SK |
621 | seqhilen += sizeof(__be32); |
622 | assoclen += seqhilen; | |
623 | } | |
624 | ||
03e2a30f SK |
625 | if (!skb_cloned(skb)) { |
626 | if (!skb_is_nonlinear(skb)) { | |
627 | nfrags = 1; | |
628 | ||
629 | goto skip_cow; | |
630 | } else if (!skb_has_frag_list(skb)) { | |
631 | nfrags = skb_shinfo(skb)->nr_frags; | |
632 | nfrags++; | |
633 | ||
634 | goto skip_cow; | |
635 | } | |
636 | } | |
637 | ||
638 | nfrags = skb_cow_data(skb, 0, &trailer); | |
639 | if (nfrags < 0) { | |
640 | ret = -EINVAL; | |
641 | goto out; | |
642 | } | |
643 | ||
644 | skip_cow: | |
645 | ret = -ENOMEM; | |
000ae7b2 | 646 | tmp = esp_alloc_tmp(aead, nfrags, seqhilen); |
38320c70 HX |
647 | if (!tmp) |
648 | goto out; | |
1da177e4 | 649 | |
38320c70 | 650 | ESP_SKB_CB(skb)->tmp = tmp; |
d212a4c2 SK |
651 | seqhi = esp_tmp_seqhi(tmp); |
652 | iv = esp_tmp_iv(aead, tmp, seqhilen); | |
38320c70 | 653 | req = esp_tmp_req(aead, iv); |
000ae7b2 | 654 | sg = esp_req_sg(aead, req); |
1da177e4 | 655 | |
03e2a30f | 656 | esp_input_set_header(skb, seqhi); |
1da177e4 | 657 | |
03e2a30f | 658 | sg_init_table(sg, nfrags); |
3f297707 | 659 | ret = skb_to_sgvec(skb, sg, 0, skb->len); |
7284fdf3 ZL |
660 | if (unlikely(ret < 0)) { |
661 | kfree(tmp); | |
3f297707 | 662 | goto out; |
7284fdf3 | 663 | } |
1da177e4 | 664 | |
03e2a30f | 665 | skb->ip_summed = CHECKSUM_NONE; |
d212a4c2 | 666 | |
03e2a30f | 667 | if ((x->props.flags & XFRM_STATE_ESN)) |
000ae7b2 | 668 | aead_request_set_callback(req, 0, esp_input_done_esn, skb); |
03e2a30f SK |
669 | else |
670 | aead_request_set_callback(req, 0, esp_input_done, skb); | |
000ae7b2 HX |
671 | |
672 | aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); | |
673 | aead_request_set_ad(req, assoclen); | |
1da177e4 | 674 | |
38320c70 HX |
675 | ret = crypto_aead_decrypt(req); |
676 | if (ret == -EINPROGRESS) | |
677 | goto out; | |
95a02cfd | 678 | |
000ae7b2 HX |
679 | if ((x->props.flags & XFRM_STATE_ESN)) |
680 | esp_input_restore_header(skb); | |
681 | ||
f1fbed0e | 682 | ret = esp6_input_done2(skb, ret); |
1da177e4 LT |
683 | |
684 | out: | |
1da177e4 LT |
685 | return ret; |
686 | } | |
687 | ||
d5860c5c SK |
688 | static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
689 | u8 type, u8 code, int offset, __be32 info) | |
1da177e4 | 690 | { |
4fb236ba | 691 | struct net *net = dev_net(skb->dev); |
b71d1d42 | 692 | const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; |
87bdc48d | 693 | struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); |
1da177e4 LT |
694 | struct xfrm_state *x; |
695 | ||
b3b2b9e1 | 696 | if (type != ICMPV6_PKT_TOOBIG && |
ec18d9a2 | 697 | type != NDISC_REDIRECT) |
d5860c5c | 698 | return 0; |
1da177e4 | 699 | |
b71d1d42 ED |
700 | x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, |
701 | esph->spi, IPPROTO_ESP, AF_INET6); | |
1da177e4 | 702 | if (!x) |
d5860c5c | 703 | return 0; |
ec18d9a2 DM |
704 | |
705 | if (type == NDISC_REDIRECT) | |
e2d118a1 LC |
706 | ip6_redirect(skb, net, skb->dev->ifindex, 0, |
707 | sock_net_uid(net, NULL)); | |
ec18d9a2 | 708 | else |
e2d118a1 | 709 | ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); |
1da177e4 | 710 | xfrm_state_put(x); |
d5860c5c SK |
711 | |
712 | return 0; | |
1da177e4 LT |
713 | } |
714 | ||
715 | static void esp6_destroy(struct xfrm_state *x) | |
716 | { | |
1c5ad13f | 717 | struct crypto_aead *aead = x->data; |
1da177e4 | 718 | |
1c5ad13f | 719 | if (!aead) |
1da177e4 LT |
720 | return; |
721 | ||
1c5ad13f | 722 | crypto_free_aead(aead); |
1da177e4 LT |
723 | } |
724 | ||
1a6509d9 HX |
725 | static int esp_init_aead(struct xfrm_state *x) |
726 | { | |
000ae7b2 | 727 | char aead_name[CRYPTO_MAX_ALG_NAME]; |
1a6509d9 HX |
728 | struct crypto_aead *aead; |
729 | int err; | |
730 | ||
000ae7b2 HX |
731 | err = -ENAMETOOLONG; |
732 | if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", | |
733 | x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) | |
734 | goto error; | |
735 | ||
f58869c4 | 736 | aead = crypto_alloc_aead(aead_name, 0, 0); |
1a6509d9 HX |
737 | err = PTR_ERR(aead); |
738 | if (IS_ERR(aead)) | |
739 | goto error; | |
740 | ||
1c5ad13f | 741 | x->data = aead; |
1a6509d9 HX |
742 | |
743 | err = crypto_aead_setkey(aead, x->aead->alg_key, | |
744 | (x->aead->alg_key_len + 7) / 8); | |
745 | if (err) | |
746 | goto error; | |
747 | ||
748 | err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); | |
749 | if (err) | |
750 | goto error; | |
751 | ||
752 | error: | |
753 | return err; | |
754 | } | |
755 | ||
756 | static int esp_init_authenc(struct xfrm_state *x) | |
1da177e4 | 757 | { |
38320c70 HX |
758 | struct crypto_aead *aead; |
759 | struct crypto_authenc_key_param *param; | |
760 | struct rtattr *rta; | |
761 | char *key; | |
762 | char *p; | |
763 | char authenc_name[CRYPTO_MAX_ALG_NAME]; | |
38320c70 HX |
764 | unsigned int keylen; |
765 | int err; | |
1da177e4 | 766 | |
1a6509d9 | 767 | err = -EINVAL; |
63159f29 | 768 | if (!x->ealg) |
1a6509d9 | 769 | goto error; |
38320c70 | 770 | |
1a6509d9 | 771 | err = -ENAMETOOLONG; |
d212a4c2 SK |
772 | |
773 | if ((x->props.flags & XFRM_STATE_ESN)) { | |
774 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
000ae7b2 HX |
775 | "%s%sauthencesn(%s,%s)%s", |
776 | x->geniv ?: "", x->geniv ? "(" : "", | |
d212a4c2 | 777 | x->aalg ? x->aalg->alg_name : "digest_null", |
000ae7b2 HX |
778 | x->ealg->alg_name, |
779 | x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) | |
d212a4c2 SK |
780 | goto error; |
781 | } else { | |
782 | if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, | |
000ae7b2 HX |
783 | "%s%sauthenc(%s,%s)%s", |
784 | x->geniv ?: "", x->geniv ? "(" : "", | |
d212a4c2 | 785 | x->aalg ? x->aalg->alg_name : "digest_null", |
000ae7b2 HX |
786 | x->ealg->alg_name, |
787 | x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) | |
d212a4c2 SK |
788 | goto error; |
789 | } | |
38320c70 | 790 | |
f58869c4 | 791 | aead = crypto_alloc_aead(authenc_name, 0, 0); |
38320c70 HX |
792 | err = PTR_ERR(aead); |
793 | if (IS_ERR(aead)) | |
794 | goto error; | |
795 | ||
1c5ad13f | 796 | x->data = aead; |
38320c70 HX |
797 | |
798 | keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + | |
799 | (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); | |
800 | err = -ENOMEM; | |
801 | key = kmalloc(keylen, GFP_KERNEL); | |
802 | if (!key) | |
803 | goto error; | |
804 | ||
805 | p = key; | |
806 | rta = (void *)p; | |
807 | rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; | |
808 | rta->rta_len = RTA_LENGTH(sizeof(*param)); | |
809 | param = RTA_DATA(rta); | |
810 | p += RTA_SPACE(sizeof(*param)); | |
811 | ||
1da177e4 LT |
812 | if (x->aalg) { |
813 | struct xfrm_algo_desc *aalg_desc; | |
814 | ||
38320c70 HX |
815 | memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); |
816 | p += (x->aalg->alg_key_len + 7) / 8; | |
1ab1457c | 817 | |
1da177e4 LT |
818 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); |
819 | BUG_ON(!aalg_desc); | |
1ab1457c | 820 | |
38320c70 | 821 | err = -EINVAL; |
45083497 | 822 | if (aalg_desc->uinfo.auth.icv_fullbits / 8 != |
38320c70 | 823 | crypto_aead_authsize(aead)) { |
45083497 JP |
824 | pr_info("ESP: %s digestsize %u != %hu\n", |
825 | x->aalg->alg_name, | |
826 | crypto_aead_authsize(aead), | |
827 | aalg_desc->uinfo.auth.icv_fullbits / 8); | |
38320c70 | 828 | goto free_key; |
1da177e4 | 829 | } |
1ab1457c | 830 | |
38320c70 | 831 | err = crypto_aead_setauthsize( |
8f8a088c | 832 | aead, x->aalg->alg_trunc_len / 8); |
38320c70 HX |
833 | if (err) |
834 | goto free_key; | |
1da177e4 | 835 | } |
38320c70 | 836 | |
38320c70 HX |
837 | param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); |
838 | memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); | |
839 | ||
840 | err = crypto_aead_setkey(aead, key, keylen); | |
841 | ||
842 | free_key: | |
843 | kfree(key); | |
844 | ||
1a6509d9 HX |
845 | error: |
846 | return err; | |
847 | } | |
848 | ||
849 | static int esp6_init_state(struct xfrm_state *x) | |
850 | { | |
1a6509d9 HX |
851 | struct crypto_aead *aead; |
852 | u32 align; | |
853 | int err; | |
854 | ||
855 | if (x->encap) | |
856 | return -EINVAL; | |
857 | ||
1c5ad13f | 858 | x->data = NULL; |
1a6509d9 HX |
859 | |
860 | if (x->aead) | |
861 | err = esp_init_aead(x); | |
862 | else | |
863 | err = esp_init_authenc(x); | |
864 | ||
38320c70 | 865 | if (err) |
1da177e4 | 866 | goto error; |
38320c70 | 867 | |
1c5ad13f | 868 | aead = x->data; |
1a6509d9 | 869 | |
38320c70 HX |
870 | x->props.header_len = sizeof(struct ip_esp_hdr) + |
871 | crypto_aead_ivsize(aead); | |
ca68145f HX |
872 | switch (x->props.mode) { |
873 | case XFRM_MODE_BEET: | |
abf5cdb8 JK |
874 | if (x->sel.family != AF_INET6) |
875 | x->props.header_len += IPV4_BEET_PHMAXLEN + | |
67ba4152 | 876 | (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); |
abf5cdb8 | 877 | break; |
bcfd09f7 | 878 | default: |
ca68145f HX |
879 | case XFRM_MODE_TRANSPORT: |
880 | break; | |
881 | case XFRM_MODE_TUNNEL: | |
1da177e4 | 882 | x->props.header_len += sizeof(struct ipv6hdr); |
ea2c47b4 | 883 | break; |
ca68145f | 884 | } |
38320c70 HX |
885 | |
886 | align = ALIGN(crypto_aead_blocksize(aead), 4); | |
1c5ad13f | 887 | x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); |
1da177e4 LT |
888 | |
889 | error: | |
38320c70 | 890 | return err; |
1da177e4 LT |
891 | } |
892 | ||
d5860c5c SK |
893 | static int esp6_rcv_cb(struct sk_buff *skb, int err) |
894 | { | |
895 | return 0; | |
896 | } | |
897 | ||
cc24beca | 898 | static const struct xfrm_type esp6_type = { |
1da177e4 | 899 | .description = "ESP6", |
cc24beca IM |
900 | .owner = THIS_MODULE, |
901 | .proto = IPPROTO_ESP, | |
436a0a40 | 902 | .flags = XFRM_TYPE_REPLAY_PROT, |
1da177e4 LT |
903 | .init_state = esp6_init_state, |
904 | .destructor = esp6_destroy, | |
1da177e4 | 905 | .input = esp6_input, |
aee5adb4 MN |
906 | .output = esp6_output, |
907 | .hdr_offset = xfrm6_find_1stfragopt, | |
1da177e4 LT |
908 | }; |
909 | ||
d5860c5c SK |
910 | static struct xfrm6_protocol esp6_protocol = { |
911 | .handler = xfrm6_rcv, | |
912 | .cb_handler = esp6_rcv_cb, | |
1da177e4 | 913 | .err_handler = esp6_err, |
d5860c5c | 914 | .priority = 0, |
1da177e4 LT |
915 | }; |
916 | ||
917 | static int __init esp6_init(void) | |
918 | { | |
919 | if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { | |
f3213831 | 920 | pr_info("%s: can't add xfrm type\n", __func__); |
1da177e4 LT |
921 | return -EAGAIN; |
922 | } | |
d5860c5c | 923 | if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { |
f3213831 | 924 | pr_info("%s: can't add protocol\n", __func__); |
1da177e4 LT |
925 | xfrm_unregister_type(&esp6_type, AF_INET6); |
926 | return -EAGAIN; | |
927 | } | |
928 | ||
929 | return 0; | |
930 | } | |
931 | ||
932 | static void __exit esp6_fini(void) | |
933 | { | |
d5860c5c | 934 | if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) |
f3213831 | 935 | pr_info("%s: can't remove protocol\n", __func__); |
4f518e80 | 936 | xfrm_unregister_type(&esp6_type, AF_INET6); |
1da177e4 LT |
937 | } |
938 | ||
939 | module_init(esp6_init); | |
940 | module_exit(esp6_fini); | |
941 | ||
942 | MODULE_LICENSE("GPL"); | |
d3d6dd3a | 943 | MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP); |