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1 /*
2 * GCM: Galois/Counter Mode.
3 *
4 * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published
8 * by the Free Software Foundation.
9 */
10
11 #include <crypto/gf128mul.h>
12 #include <crypto/internal/aead.h>
13 #include <crypto/internal/skcipher.h>
14 #include <crypto/internal/hash.h>
15 #include <crypto/null.h>
16 #include <crypto/scatterwalk.h>
17 #include <crypto/hash.h>
18 #include "internal.h"
19 #include <linux/completion.h>
20 #include <linux/err.h>
21 #include <linux/init.h>
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/slab.h>
25
26 struct gcm_instance_ctx {
27 struct crypto_skcipher_spawn ctr;
28 struct crypto_ahash_spawn ghash;
29 };
30
31 struct crypto_gcm_ctx {
32 struct crypto_ablkcipher *ctr;
33 struct crypto_ahash *ghash;
34 };
35
36 struct crypto_rfc4106_ctx {
37 struct crypto_aead *child;
38 u8 nonce[4];
39 };
40
41 struct crypto_rfc4543_instance_ctx {
42 struct crypto_aead_spawn aead;
43 };
44
45 struct crypto_rfc4543_ctx {
46 struct crypto_aead *child;
47 struct crypto_blkcipher *null;
48 u8 nonce[4];
49 };
50
51 struct crypto_rfc4543_req_ctx {
52 struct aead_request subreq;
53 };
54
55 struct crypto_gcm_ghash_ctx {
56 unsigned int cryptlen;
57 struct scatterlist *src;
58 int (*complete)(struct aead_request *req, u32 flags);
59 };
60
61 struct crypto_gcm_req_priv_ctx {
62 u8 iv[16];
63 u8 auth_tag[16];
64 u8 iauth_tag[16];
65 struct scatterlist src[3];
66 struct scatterlist dst[3];
67 struct scatterlist sg;
68 struct crypto_gcm_ghash_ctx ghash_ctx;
69 union {
70 struct ahash_request ahreq;
71 struct ablkcipher_request abreq;
72 } u;
73 };
74
75 struct crypto_gcm_setkey_result {
76 int err;
77 struct completion completion;
78 };
79
80 static struct {
81 u8 buf[16];
82 struct scatterlist sg;
83 } *gcm_zeroes;
84
85 static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
86
87 static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
88 struct aead_request *req)
89 {
90 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
91
92 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
93 }
94
95 static void crypto_gcm_setkey_done(struct crypto_async_request *req, int err)
96 {
97 struct crypto_gcm_setkey_result *result = req->data;
98
99 if (err == -EINPROGRESS)
100 return;
101
102 result->err = err;
103 complete(&result->completion);
104 }
105
106 static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
107 unsigned int keylen)
108 {
109 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
110 struct crypto_ahash *ghash = ctx->ghash;
111 struct crypto_ablkcipher *ctr = ctx->ctr;
112 struct {
113 be128 hash;
114 u8 iv[8];
115
116 struct crypto_gcm_setkey_result result;
117
118 struct scatterlist sg[1];
119 struct ablkcipher_request req;
120 } *data;
121 int err;
122
123 crypto_ablkcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
124 crypto_ablkcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
125 CRYPTO_TFM_REQ_MASK);
126 err = crypto_ablkcipher_setkey(ctr, key, keylen);
127 crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) &
128 CRYPTO_TFM_RES_MASK);
129 if (err)
130 return err;
131
132 data = kzalloc(sizeof(*data) + crypto_ablkcipher_reqsize(ctr),
133 GFP_KERNEL);
134 if (!data)
135 return -ENOMEM;
136
137 init_completion(&data->result.completion);
138 sg_init_one(data->sg, &data->hash, sizeof(data->hash));
139 ablkcipher_request_set_tfm(&data->req, ctr);
140 ablkcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
141 CRYPTO_TFM_REQ_MAY_BACKLOG,
142 crypto_gcm_setkey_done,
143 &data->result);
144 ablkcipher_request_set_crypt(&data->req, data->sg, data->sg,
145 sizeof(data->hash), data->iv);
146
147 err = crypto_ablkcipher_encrypt(&data->req);
148 if (err == -EINPROGRESS || err == -EBUSY) {
149 err = wait_for_completion_interruptible(
150 &data->result.completion);
151 if (!err)
152 err = data->result.err;
153 }
154
155 if (err)
156 goto out;
157
158 crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
159 crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
160 CRYPTO_TFM_REQ_MASK);
161 err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
162 crypto_aead_set_flags(aead, crypto_ahash_get_flags(ghash) &
163 CRYPTO_TFM_RES_MASK);
164
165 out:
166 kzfree(data);
167 return err;
168 }
169
170 static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
171 unsigned int authsize)
172 {
173 switch (authsize) {
174 case 4:
175 case 8:
176 case 12:
177 case 13:
178 case 14:
179 case 15:
180 case 16:
181 break;
182 default:
183 return -EINVAL;
184 }
185
186 return 0;
187 }
188
189 static void crypto_gcm_init_common(struct aead_request *req)
190 {
191 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
192 __be32 counter = cpu_to_be32(1);
193 struct scatterlist *sg;
194
195 memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
196 memcpy(pctx->iv, req->iv, 12);
197 memcpy(pctx->iv + 12, &counter, 4);
198
199 sg_init_table(pctx->src, 3);
200 sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
201 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
202 if (sg != pctx->src + 1)
203 scatterwalk_sg_chain(pctx->src, 2, sg);
204
205 if (req->src != req->dst) {
206 sg_init_table(pctx->dst, 3);
207 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
208 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
209 if (sg != pctx->dst + 1)
210 scatterwalk_sg_chain(pctx->dst, 2, sg);
211 }
212 }
213
214 static void crypto_gcm_init_crypt(struct aead_request *req,
215 unsigned int cryptlen)
216 {
217 struct crypto_aead *aead = crypto_aead_reqtfm(req);
218 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
219 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
220 struct ablkcipher_request *ablk_req = &pctx->u.abreq;
221 struct scatterlist *dst;
222
223 dst = req->src == req->dst ? pctx->src : pctx->dst;
224
225 ablkcipher_request_set_tfm(ablk_req, ctx->ctr);
226 ablkcipher_request_set_crypt(ablk_req, pctx->src, dst,
227 cryptlen + sizeof(pctx->auth_tag),
228 pctx->iv);
229 }
230
231 static inline unsigned int gcm_remain(unsigned int len)
232 {
233 len &= 0xfU;
234 return len ? 16 - len : 0;
235 }
236
237 static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
238
239 static int gcm_hash_update(struct aead_request *req,
240 crypto_completion_t compl,
241 struct scatterlist *src,
242 unsigned int len, u32 flags)
243 {
244 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
245 struct ahash_request *ahreq = &pctx->u.ahreq;
246
247 ahash_request_set_callback(ahreq, flags, compl, req);
248 ahash_request_set_crypt(ahreq, src, NULL, len);
249
250 return crypto_ahash_update(ahreq);
251 }
252
253 static int gcm_hash_remain(struct aead_request *req,
254 unsigned int remain,
255 crypto_completion_t compl, u32 flags)
256 {
257 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
258 }
259
260 static int gcm_hash_len(struct aead_request *req, u32 flags)
261 {
262 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
263 struct ahash_request *ahreq = &pctx->u.ahreq;
264 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
265 u128 lengths;
266
267 lengths.a = cpu_to_be64(req->assoclen * 8);
268 lengths.b = cpu_to_be64(gctx->cryptlen * 8);
269 memcpy(pctx->iauth_tag, &lengths, 16);
270 sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
271 ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
272 ahash_request_set_crypt(ahreq, &pctx->sg,
273 pctx->iauth_tag, sizeof(lengths));
274
275 return crypto_ahash_finup(ahreq);
276 }
277
278 static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
279 {
280 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
281 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
282
283 return gctx->complete(req, flags);
284 }
285
286 static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
287 {
288 struct aead_request *req = areq->data;
289
290 if (err)
291 goto out;
292
293 err = gcm_hash_len_continue(req, 0);
294 if (err == -EINPROGRESS)
295 return;
296
297 out:
298 aead_request_complete(req, err);
299 }
300
301 static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
302 {
303 return gcm_hash_len(req, flags) ?:
304 gcm_hash_len_continue(req, flags);
305 }
306
307 static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
308 int err)
309 {
310 struct aead_request *req = areq->data;
311
312 if (err)
313 goto out;
314
315 err = gcm_hash_crypt_remain_continue(req, 0);
316 if (err == -EINPROGRESS)
317 return;
318
319 out:
320 aead_request_complete(req, err);
321 }
322
323 static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
324 {
325 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
326 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
327 unsigned int remain;
328
329 remain = gcm_remain(gctx->cryptlen);
330 if (remain)
331 return gcm_hash_remain(req, remain,
332 gcm_hash_crypt_remain_done, flags) ?:
333 gcm_hash_crypt_remain_continue(req, flags);
334
335 return gcm_hash_crypt_remain_continue(req, flags);
336 }
337
338 static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
339 {
340 struct aead_request *req = areq->data;
341
342 if (err)
343 goto out;
344
345 err = gcm_hash_crypt_continue(req, 0);
346 if (err == -EINPROGRESS)
347 return;
348
349 out:
350 aead_request_complete(req, err);
351 }
352
353 static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
354 {
355 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
356 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
357
358 if (gctx->cryptlen)
359 return gcm_hash_update(req, gcm_hash_crypt_done,
360 gctx->src, gctx->cryptlen, flags) ?:
361 gcm_hash_crypt_continue(req, flags);
362
363 return gcm_hash_crypt_remain_continue(req, flags);
364 }
365
366 static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
367 int err)
368 {
369 struct aead_request *req = areq->data;
370
371 if (err)
372 goto out;
373
374 err = gcm_hash_assoc_remain_continue(req, 0);
375 if (err == -EINPROGRESS)
376 return;
377
378 out:
379 aead_request_complete(req, err);
380 }
381
382 static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
383 {
384 unsigned int remain;
385
386 remain = gcm_remain(req->assoclen);
387 if (remain)
388 return gcm_hash_remain(req, remain,
389 gcm_hash_assoc_remain_done, flags) ?:
390 gcm_hash_assoc_remain_continue(req, flags);
391
392 return gcm_hash_assoc_remain_continue(req, flags);
393 }
394
395 static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
396 {
397 struct aead_request *req = areq->data;
398
399 if (err)
400 goto out;
401
402 err = gcm_hash_assoc_continue(req, 0);
403 if (err == -EINPROGRESS)
404 return;
405
406 out:
407 aead_request_complete(req, err);
408 }
409
410 static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
411 {
412 if (req->assoclen)
413 return gcm_hash_update(req, gcm_hash_assoc_done,
414 req->src, req->assoclen, flags) ?:
415 gcm_hash_assoc_continue(req, flags);
416
417 return gcm_hash_assoc_remain_continue(req, flags);
418 }
419
420 static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
421 {
422 struct aead_request *req = areq->data;
423
424 if (err)
425 goto out;
426
427 err = gcm_hash_init_continue(req, 0);
428 if (err == -EINPROGRESS)
429 return;
430
431 out:
432 aead_request_complete(req, err);
433 }
434
435 static int gcm_hash(struct aead_request *req, u32 flags)
436 {
437 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
438 struct ahash_request *ahreq = &pctx->u.ahreq;
439 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
440
441 ahash_request_set_tfm(ahreq, ctx->ghash);
442
443 ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
444 return crypto_ahash_init(ahreq) ?:
445 gcm_hash_init_continue(req, flags);
446 }
447
448 static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
449 {
450 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
451 struct crypto_aead *aead = crypto_aead_reqtfm(req);
452 u8 *auth_tag = pctx->auth_tag;
453
454 crypto_xor(auth_tag, pctx->iauth_tag, 16);
455 scatterwalk_map_and_copy(auth_tag, req->dst,
456 req->assoclen + req->cryptlen,
457 crypto_aead_authsize(aead), 1);
458 return 0;
459 }
460
461 static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
462 {
463 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
464 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
465
466 gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
467 gctx->cryptlen = req->cryptlen;
468 gctx->complete = gcm_enc_copy_hash;
469
470 return gcm_hash(req, flags);
471 }
472
473 static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
474 {
475 struct aead_request *req = areq->data;
476
477 if (err)
478 goto out;
479
480 err = gcm_encrypt_continue(req, 0);
481 if (err == -EINPROGRESS)
482 return;
483
484 out:
485 aead_request_complete(req, err);
486 }
487
488 static int crypto_gcm_encrypt(struct aead_request *req)
489 {
490 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
491 struct ablkcipher_request *abreq = &pctx->u.abreq;
492 u32 flags = aead_request_flags(req);
493
494 crypto_gcm_init_common(req);
495 crypto_gcm_init_crypt(req, req->cryptlen);
496 ablkcipher_request_set_callback(abreq, flags, gcm_encrypt_done, req);
497
498 return crypto_ablkcipher_encrypt(abreq) ?:
499 gcm_encrypt_continue(req, flags);
500 }
501
502 static int crypto_gcm_verify(struct aead_request *req)
503 {
504 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
505 struct crypto_aead *aead = crypto_aead_reqtfm(req);
506 u8 *auth_tag = pctx->auth_tag;
507 u8 *iauth_tag = pctx->iauth_tag;
508 unsigned int authsize = crypto_aead_authsize(aead);
509 unsigned int cryptlen = req->cryptlen - authsize;
510
511 crypto_xor(auth_tag, iauth_tag, 16);
512 scatterwalk_map_and_copy(iauth_tag, req->src,
513 req->assoclen + cryptlen, authsize, 0);
514 return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
515 }
516
517 static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
518 {
519 struct aead_request *req = areq->data;
520
521 if (!err)
522 err = crypto_gcm_verify(req);
523
524 aead_request_complete(req, err);
525 }
526
527 static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
528 {
529 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
530 struct ablkcipher_request *abreq = &pctx->u.abreq;
531 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
532
533 crypto_gcm_init_crypt(req, gctx->cryptlen);
534 ablkcipher_request_set_callback(abreq, flags, gcm_decrypt_done, req);
535 return crypto_ablkcipher_decrypt(abreq) ?: crypto_gcm_verify(req);
536 }
537
538 static int crypto_gcm_decrypt(struct aead_request *req)
539 {
540 struct crypto_aead *aead = crypto_aead_reqtfm(req);
541 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
542 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
543 unsigned int authsize = crypto_aead_authsize(aead);
544 unsigned int cryptlen = req->cryptlen;
545 u32 flags = aead_request_flags(req);
546
547 cryptlen -= authsize;
548
549 crypto_gcm_init_common(req);
550
551 gctx->src = sg_next(pctx->src);
552 gctx->cryptlen = cryptlen;
553 gctx->complete = gcm_dec_hash_continue;
554
555 return gcm_hash(req, flags);
556 }
557
558 static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
559 {
560 struct aead_instance *inst = aead_alg_instance(tfm);
561 struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
562 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
563 struct crypto_ablkcipher *ctr;
564 struct crypto_ahash *ghash;
565 unsigned long align;
566 int err;
567
568 ghash = crypto_spawn_ahash(&ictx->ghash);
569 if (IS_ERR(ghash))
570 return PTR_ERR(ghash);
571
572 ctr = crypto_spawn_skcipher(&ictx->ctr);
573 err = PTR_ERR(ctr);
574 if (IS_ERR(ctr))
575 goto err_free_hash;
576
577 ctx->ctr = ctr;
578 ctx->ghash = ghash;
579
580 align = crypto_aead_alignmask(tfm);
581 align &= ~(crypto_tfm_ctx_alignment() - 1);
582 crypto_aead_set_reqsize(tfm,
583 align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
584 max(sizeof(struct ablkcipher_request) +
585 crypto_ablkcipher_reqsize(ctr),
586 sizeof(struct ahash_request) +
587 crypto_ahash_reqsize(ghash)));
588
589 return 0;
590
591 err_free_hash:
592 crypto_free_ahash(ghash);
593 return err;
594 }
595
596 static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
597 {
598 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
599
600 crypto_free_ahash(ctx->ghash);
601 crypto_free_ablkcipher(ctx->ctr);
602 }
603
604 static int crypto_gcm_create_common(struct crypto_template *tmpl,
605 struct rtattr **tb,
606 const char *full_name,
607 const char *ctr_name,
608 const char *ghash_name)
609 {
610 struct crypto_attr_type *algt;
611 struct aead_instance *inst;
612 struct crypto_alg *ctr;
613 struct crypto_alg *ghash_alg;
614 struct hash_alg_common *ghash;
615 struct gcm_instance_ctx *ctx;
616 int err;
617
618 algt = crypto_get_attr_type(tb);
619 if (IS_ERR(algt))
620 return PTR_ERR(algt);
621
622 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
623 return -EINVAL;
624
625 ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
626 CRYPTO_ALG_TYPE_HASH,
627 CRYPTO_ALG_TYPE_AHASH_MASK);
628 if (IS_ERR(ghash_alg))
629 return PTR_ERR(ghash_alg);
630
631 ghash = __crypto_hash_alg_common(ghash_alg);
632
633 err = -ENOMEM;
634 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
635 if (!inst)
636 goto out_put_ghash;
637
638 ctx = aead_instance_ctx(inst);
639 err = crypto_init_ahash_spawn(&ctx->ghash, ghash,
640 aead_crypto_instance(inst));
641 if (err)
642 goto err_free_inst;
643
644 err = -EINVAL;
645 if (ghash->digestsize != 16)
646 goto err_drop_ghash;
647
648 crypto_set_skcipher_spawn(&ctx->ctr, aead_crypto_instance(inst));
649 err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
650 crypto_requires_sync(algt->type,
651 algt->mask));
652 if (err)
653 goto err_drop_ghash;
654
655 ctr = crypto_skcipher_spawn_alg(&ctx->ctr);
656
657 /* We only support 16-byte blocks. */
658 if (ctr->cra_ablkcipher.ivsize != 16)
659 goto out_put_ctr;
660
661 /* Not a stream cipher? */
662 err = -EINVAL;
663 if (ctr->cra_blocksize != 1)
664 goto out_put_ctr;
665
666 err = -ENAMETOOLONG;
667 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
668 "gcm_base(%s,%s)", ctr->cra_driver_name,
669 ghash_alg->cra_driver_name) >=
670 CRYPTO_MAX_ALG_NAME)
671 goto out_put_ctr;
672
673 memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
674
675 inst->alg.base.cra_flags = (ghash->base.cra_flags | ctr->cra_flags) &
676 CRYPTO_ALG_ASYNC;
677 inst->alg.base.cra_priority = (ghash->base.cra_priority +
678 ctr->cra_priority) / 2;
679 inst->alg.base.cra_blocksize = 1;
680 inst->alg.base.cra_alignmask = ghash->base.cra_alignmask |
681 ctr->cra_alignmask;
682 inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
683 inst->alg.ivsize = 12;
684 inst->alg.maxauthsize = 16;
685 inst->alg.init = crypto_gcm_init_tfm;
686 inst->alg.exit = crypto_gcm_exit_tfm;
687 inst->alg.setkey = crypto_gcm_setkey;
688 inst->alg.setauthsize = crypto_gcm_setauthsize;
689 inst->alg.encrypt = crypto_gcm_encrypt;
690 inst->alg.decrypt = crypto_gcm_decrypt;
691
692 err = aead_register_instance(tmpl, inst);
693 if (err)
694 goto out_put_ctr;
695
696 out_put_ghash:
697 crypto_mod_put(ghash_alg);
698 return err;
699
700 out_put_ctr:
701 crypto_drop_skcipher(&ctx->ctr);
702 err_drop_ghash:
703 crypto_drop_ahash(&ctx->ghash);
704 err_free_inst:
705 kfree(inst);
706 goto out_put_ghash;
707 }
708
709 static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
710 {
711 const char *cipher_name;
712 char ctr_name[CRYPTO_MAX_ALG_NAME];
713 char full_name[CRYPTO_MAX_ALG_NAME];
714
715 cipher_name = crypto_attr_alg_name(tb[1]);
716 if (IS_ERR(cipher_name))
717 return PTR_ERR(cipher_name);
718
719 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
720 CRYPTO_MAX_ALG_NAME)
721 return -ENAMETOOLONG;
722
723 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >=
724 CRYPTO_MAX_ALG_NAME)
725 return -ENAMETOOLONG;
726
727 return crypto_gcm_create_common(tmpl, tb, full_name,
728 ctr_name, "ghash");
729 }
730
731 static void crypto_gcm_free(struct crypto_instance *inst)
732 {
733 struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst);
734
735 crypto_drop_skcipher(&ctx->ctr);
736 crypto_drop_ahash(&ctx->ghash);
737 kfree(aead_instance(inst));
738 }
739
740 static struct crypto_template crypto_gcm_tmpl = {
741 .name = "gcm",
742 .create = crypto_gcm_create,
743 .free = crypto_gcm_free,
744 .module = THIS_MODULE,
745 };
746
747 static int crypto_gcm_base_create(struct crypto_template *tmpl,
748 struct rtattr **tb)
749 {
750 const char *ctr_name;
751 const char *ghash_name;
752 char full_name[CRYPTO_MAX_ALG_NAME];
753
754 ctr_name = crypto_attr_alg_name(tb[1]);
755 if (IS_ERR(ctr_name))
756 return PTR_ERR(ctr_name);
757
758 ghash_name = crypto_attr_alg_name(tb[2]);
759 if (IS_ERR(ghash_name))
760 return PTR_ERR(ghash_name);
761
762 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)",
763 ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME)
764 return -ENAMETOOLONG;
765
766 return crypto_gcm_create_common(tmpl, tb, full_name,
767 ctr_name, ghash_name);
768 }
769
770 static struct crypto_template crypto_gcm_base_tmpl = {
771 .name = "gcm_base",
772 .create = crypto_gcm_base_create,
773 .free = crypto_gcm_free,
774 .module = THIS_MODULE,
775 };
776
777 static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
778 unsigned int keylen)
779 {
780 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
781 struct crypto_aead *child = ctx->child;
782 int err;
783
784 if (keylen < 4)
785 return -EINVAL;
786
787 keylen -= 4;
788 memcpy(ctx->nonce, key + keylen, 4);
789
790 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
791 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
792 CRYPTO_TFM_REQ_MASK);
793 err = crypto_aead_setkey(child, key, keylen);
794 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
795 CRYPTO_TFM_RES_MASK);
796
797 return err;
798 }
799
800 static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
801 unsigned int authsize)
802 {
803 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
804
805 switch (authsize) {
806 case 8:
807 case 12:
808 case 16:
809 break;
810 default:
811 return -EINVAL;
812 }
813
814 return crypto_aead_setauthsize(ctx->child, authsize);
815 }
816
817 static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
818 {
819 struct aead_request *subreq = aead_request_ctx(req);
820 struct crypto_aead *aead = crypto_aead_reqtfm(req);
821 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
822 struct crypto_aead *child = ctx->child;
823 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
824 crypto_aead_alignmask(child) + 1);
825
826 memcpy(iv, ctx->nonce, 4);
827 memcpy(iv + 4, req->iv, 8);
828
829 aead_request_set_tfm(subreq, child);
830 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
831 req->base.data);
832 aead_request_set_crypt(subreq, req->src, req->dst, req->cryptlen, iv);
833 aead_request_set_ad(subreq, req->assoclen);
834
835 return subreq;
836 }
837
838 static int crypto_rfc4106_encrypt(struct aead_request *req)
839 {
840 req = crypto_rfc4106_crypt(req);
841
842 return crypto_aead_encrypt(req);
843 }
844
845 static int crypto_rfc4106_decrypt(struct aead_request *req)
846 {
847 req = crypto_rfc4106_crypt(req);
848
849 return crypto_aead_decrypt(req);
850 }
851
852 static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
853 {
854 struct aead_instance *inst = aead_alg_instance(tfm);
855 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
856 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
857 struct crypto_aead *aead;
858 unsigned long align;
859
860 aead = crypto_spawn_aead(spawn);
861 if (IS_ERR(aead))
862 return PTR_ERR(aead);
863
864 ctx->child = aead;
865
866 align = crypto_aead_alignmask(aead);
867 align &= ~(crypto_tfm_ctx_alignment() - 1);
868 crypto_aead_set_reqsize(
869 tfm,
870 sizeof(struct aead_request) +
871 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
872 align + 12);
873
874 return 0;
875 }
876
877 static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
878 {
879 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
880
881 crypto_free_aead(ctx->child);
882 }
883
884 static int crypto_rfc4106_create(struct crypto_template *tmpl,
885 struct rtattr **tb)
886 {
887 struct crypto_attr_type *algt;
888 struct aead_instance *inst;
889 struct crypto_aead_spawn *spawn;
890 struct aead_alg *alg;
891 const char *ccm_name;
892 int err;
893
894 algt = crypto_get_attr_type(tb);
895 if (IS_ERR(algt))
896 return PTR_ERR(algt);
897
898 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
899 return -EINVAL;
900
901 ccm_name = crypto_attr_alg_name(tb[1]);
902 if (IS_ERR(ccm_name))
903 return PTR_ERR(ccm_name);
904
905 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
906 if (!inst)
907 return -ENOMEM;
908
909 spawn = aead_instance_ctx(inst);
910 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
911 err = crypto_grab_aead(spawn, ccm_name, 0,
912 crypto_requires_sync(algt->type, algt->mask));
913 if (err)
914 goto out_free_inst;
915
916 alg = crypto_spawn_aead_alg(spawn);
917
918 err = -EINVAL;
919
920 /* Underlying IV size must be 12. */
921 if (crypto_aead_alg_ivsize(alg) != 12)
922 goto out_drop_alg;
923
924 /* Not a stream cipher? */
925 if (alg->base.cra_blocksize != 1)
926 goto out_drop_alg;
927
928 err = -ENAMETOOLONG;
929 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
930 "rfc4106(%s)", alg->base.cra_name) >=
931 CRYPTO_MAX_ALG_NAME ||
932 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
933 "rfc4106(%s)", alg->base.cra_driver_name) >=
934 CRYPTO_MAX_ALG_NAME)
935 goto out_drop_alg;
936
937 inst->alg.base.cra_flags |= alg->base.cra_flags & CRYPTO_ALG_ASYNC;
938 inst->alg.base.cra_priority = alg->base.cra_priority;
939 inst->alg.base.cra_blocksize = 1;
940 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
941
942 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
943
944 inst->alg.ivsize = 8;
945 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
946
947 inst->alg.init = crypto_rfc4106_init_tfm;
948 inst->alg.exit = crypto_rfc4106_exit_tfm;
949
950 inst->alg.setkey = crypto_rfc4106_setkey;
951 inst->alg.setauthsize = crypto_rfc4106_setauthsize;
952 inst->alg.encrypt = crypto_rfc4106_encrypt;
953 inst->alg.decrypt = crypto_rfc4106_decrypt;
954
955 err = aead_register_instance(tmpl, inst);
956 if (err)
957 goto out_drop_alg;
958
959 out:
960 return err;
961
962 out_drop_alg:
963 crypto_drop_aead(spawn);
964 out_free_inst:
965 kfree(inst);
966 goto out;
967 }
968
969 static void crypto_rfc4106_free(struct crypto_instance *inst)
970 {
971 crypto_drop_aead(crypto_instance_ctx(inst));
972 kfree(aead_instance(inst));
973 }
974
975 static struct crypto_template crypto_rfc4106_tmpl = {
976 .name = "rfc4106",
977 .create = crypto_rfc4106_create,
978 .free = crypto_rfc4106_free,
979 .module = THIS_MODULE,
980 };
981
982 static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
983 unsigned int keylen)
984 {
985 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
986 struct crypto_aead *child = ctx->child;
987 int err;
988
989 if (keylen < 4)
990 return -EINVAL;
991
992 keylen -= 4;
993 memcpy(ctx->nonce, key + keylen, 4);
994
995 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
996 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
997 CRYPTO_TFM_REQ_MASK);
998 err = crypto_aead_setkey(child, key, keylen);
999 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
1000 CRYPTO_TFM_RES_MASK);
1001
1002 return err;
1003 }
1004
1005 static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
1006 unsigned int authsize)
1007 {
1008 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
1009
1010 if (authsize != 16)
1011 return -EINVAL;
1012
1013 return crypto_aead_setauthsize(ctx->child, authsize);
1014 }
1015
1016 static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
1017 {
1018 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1019 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1020 struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
1021 struct aead_request *subreq = &rctx->subreq;
1022 unsigned int authsize = crypto_aead_authsize(aead);
1023 u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
1024 crypto_aead_alignmask(ctx->child) + 1);
1025 int err;
1026
1027 if (req->src != req->dst) {
1028 err = crypto_rfc4543_copy_src_to_dst(req, enc);
1029 if (err)
1030 return err;
1031 }
1032
1033 memcpy(iv, ctx->nonce, 4);
1034 memcpy(iv + 4, req->iv, 8);
1035
1036 aead_request_set_tfm(subreq, ctx->child);
1037 aead_request_set_callback(subreq, req->base.flags,
1038 req->base.complete, req->base.data);
1039 aead_request_set_crypt(subreq, req->src, req->dst,
1040 enc ? 0 : authsize, iv);
1041 aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
1042 subreq->cryptlen);
1043
1044 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
1045 }
1046
1047 static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
1048 {
1049 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1050 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1051 unsigned int authsize = crypto_aead_authsize(aead);
1052 unsigned int nbytes = req->assoclen + req->cryptlen -
1053 (enc ? 0 : authsize);
1054 struct blkcipher_desc desc = {
1055 .tfm = ctx->null,
1056 };
1057
1058 return crypto_blkcipher_encrypt(&desc, req->dst, req->src, nbytes);
1059 }
1060
1061 static int crypto_rfc4543_encrypt(struct aead_request *req)
1062 {
1063 return crypto_rfc4543_crypt(req, true);
1064 }
1065
1066 static int crypto_rfc4543_decrypt(struct aead_request *req)
1067 {
1068 return crypto_rfc4543_crypt(req, false);
1069 }
1070
1071 static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
1072 {
1073 struct aead_instance *inst = aead_alg_instance(tfm);
1074 struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst);
1075 struct crypto_aead_spawn *spawn = &ictx->aead;
1076 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1077 struct crypto_aead *aead;
1078 struct crypto_blkcipher *null;
1079 unsigned long align;
1080 int err = 0;
1081
1082 aead = crypto_spawn_aead(spawn);
1083 if (IS_ERR(aead))
1084 return PTR_ERR(aead);
1085
1086 null = crypto_get_default_null_skcipher();
1087 err = PTR_ERR(null);
1088 if (IS_ERR(null))
1089 goto err_free_aead;
1090
1091 ctx->child = aead;
1092 ctx->null = null;
1093
1094 align = crypto_aead_alignmask(aead);
1095 align &= ~(crypto_tfm_ctx_alignment() - 1);
1096 crypto_aead_set_reqsize(
1097 tfm,
1098 sizeof(struct crypto_rfc4543_req_ctx) +
1099 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
1100 align + 12);
1101
1102 return 0;
1103
1104 err_free_aead:
1105 crypto_free_aead(aead);
1106 return err;
1107 }
1108
1109 static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
1110 {
1111 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1112
1113 crypto_free_aead(ctx->child);
1114 crypto_put_default_null_skcipher();
1115 }
1116
1117 static int crypto_rfc4543_create(struct crypto_template *tmpl,
1118 struct rtattr **tb)
1119 {
1120 struct crypto_attr_type *algt;
1121 struct aead_instance *inst;
1122 struct crypto_aead_spawn *spawn;
1123 struct aead_alg *alg;
1124 struct crypto_rfc4543_instance_ctx *ctx;
1125 const char *ccm_name;
1126 int err;
1127
1128 algt = crypto_get_attr_type(tb);
1129 if (IS_ERR(algt))
1130 return PTR_ERR(algt);
1131
1132 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
1133 return -EINVAL;
1134
1135 ccm_name = crypto_attr_alg_name(tb[1]);
1136 if (IS_ERR(ccm_name))
1137 return PTR_ERR(ccm_name);
1138
1139 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1140 if (!inst)
1141 return -ENOMEM;
1142
1143 ctx = aead_instance_ctx(inst);
1144 spawn = &ctx->aead;
1145 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
1146 err = crypto_grab_aead(spawn, ccm_name, 0,
1147 crypto_requires_sync(algt->type, algt->mask));
1148 if (err)
1149 goto out_free_inst;
1150
1151 alg = crypto_spawn_aead_alg(spawn);
1152
1153 err = -EINVAL;
1154
1155 /* Underlying IV size must be 12. */
1156 if (crypto_aead_alg_ivsize(alg) != 12)
1157 goto out_drop_alg;
1158
1159 /* Not a stream cipher? */
1160 if (alg->base.cra_blocksize != 1)
1161 goto out_drop_alg;
1162
1163 err = -ENAMETOOLONG;
1164 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
1165 "rfc4543(%s)", alg->base.cra_name) >=
1166 CRYPTO_MAX_ALG_NAME ||
1167 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1168 "rfc4543(%s)", alg->base.cra_driver_name) >=
1169 CRYPTO_MAX_ALG_NAME)
1170 goto out_drop_alg;
1171
1172 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
1173 inst->alg.base.cra_priority = alg->base.cra_priority;
1174 inst->alg.base.cra_blocksize = 1;
1175 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
1176
1177 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
1178
1179 inst->alg.ivsize = 8;
1180 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
1181
1182 inst->alg.init = crypto_rfc4543_init_tfm;
1183 inst->alg.exit = crypto_rfc4543_exit_tfm;
1184
1185 inst->alg.setkey = crypto_rfc4543_setkey;
1186 inst->alg.setauthsize = crypto_rfc4543_setauthsize;
1187 inst->alg.encrypt = crypto_rfc4543_encrypt;
1188 inst->alg.decrypt = crypto_rfc4543_decrypt;
1189
1190 err = aead_register_instance(tmpl, inst);
1191 if (err)
1192 goto out_drop_alg;
1193
1194 out:
1195 return err;
1196
1197 out_drop_alg:
1198 crypto_drop_aead(spawn);
1199 out_free_inst:
1200 kfree(inst);
1201 goto out;
1202 }
1203
1204 static void crypto_rfc4543_free(struct crypto_instance *inst)
1205 {
1206 struct crypto_rfc4543_instance_ctx *ctx = crypto_instance_ctx(inst);
1207
1208 crypto_drop_aead(&ctx->aead);
1209
1210 kfree(aead_instance(inst));
1211 }
1212
1213 static struct crypto_template crypto_rfc4543_tmpl = {
1214 .name = "rfc4543",
1215 .create = crypto_rfc4543_create,
1216 .free = crypto_rfc4543_free,
1217 .module = THIS_MODULE,
1218 };
1219
1220 static int __init crypto_gcm_module_init(void)
1221 {
1222 int err;
1223
1224 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
1225 if (!gcm_zeroes)
1226 return -ENOMEM;
1227
1228 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
1229
1230 err = crypto_register_template(&crypto_gcm_base_tmpl);
1231 if (err)
1232 goto out;
1233
1234 err = crypto_register_template(&crypto_gcm_tmpl);
1235 if (err)
1236 goto out_undo_base;
1237
1238 err = crypto_register_template(&crypto_rfc4106_tmpl);
1239 if (err)
1240 goto out_undo_gcm;
1241
1242 err = crypto_register_template(&crypto_rfc4543_tmpl);
1243 if (err)
1244 goto out_undo_rfc4106;
1245
1246 return 0;
1247
1248 out_undo_rfc4106:
1249 crypto_unregister_template(&crypto_rfc4106_tmpl);
1250 out_undo_gcm:
1251 crypto_unregister_template(&crypto_gcm_tmpl);
1252 out_undo_base:
1253 crypto_unregister_template(&crypto_gcm_base_tmpl);
1254 out:
1255 kfree(gcm_zeroes);
1256 return err;
1257 }
1258
1259 static void __exit crypto_gcm_module_exit(void)
1260 {
1261 kfree(gcm_zeroes);
1262 crypto_unregister_template(&crypto_rfc4543_tmpl);
1263 crypto_unregister_template(&crypto_rfc4106_tmpl);
1264 crypto_unregister_template(&crypto_gcm_tmpl);
1265 crypto_unregister_template(&crypto_gcm_base_tmpl);
1266 }
1267
1268 module_init(crypto_gcm_module_init);
1269 module_exit(crypto_gcm_module_exit);
1270
1271 MODULE_LICENSE("GPL");
1272 MODULE_DESCRIPTION("Galois/Counter Mode");
1273 MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1274 MODULE_ALIAS_CRYPTO("gcm_base");
1275 MODULE_ALIAS_CRYPTO("rfc4106");
1276 MODULE_ALIAS_CRYPTO("rfc4543");
1277 MODULE_ALIAS_CRYPTO("gcm");