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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
26struct gcm_instance_ctx {
27 struct crypto_skcipher_spawn ctr;
28 struct crypto_ahash_spawn ghash;
29};
30
31struct crypto_gcm_ctx {
32 struct crypto_ablkcipher *ctr;
33 struct crypto_ahash *ghash;
34};
35
36struct crypto_rfc4106_ctx {
37 struct crypto_aead *child;
38 u8 nonce[4];
39};
40
41struct crypto_rfc4106_req_ctx {
42 struct scatterlist src[3];
43 struct scatterlist dst[3];
44 struct aead_request subreq;
45};
46
47struct crypto_rfc4543_instance_ctx {
48 struct crypto_aead_spawn aead;
49};
50
51struct crypto_rfc4543_ctx {
52 struct crypto_aead *child;
53 struct crypto_blkcipher *null;
54 u8 nonce[4];
55};
56
57struct crypto_rfc4543_req_ctx {
58 struct aead_request subreq;
59};
60
61struct crypto_gcm_ghash_ctx {
62 unsigned int cryptlen;
63 struct scatterlist *src;
64 int (*complete)(struct aead_request *req, u32 flags);
65};
66
67struct crypto_gcm_req_priv_ctx {
68 u8 iv[16];
69 u8 auth_tag[16];
70 u8 iauth_tag[16];
71 struct scatterlist src[3];
72 struct scatterlist dst[3];
73 struct scatterlist sg;
74 struct crypto_gcm_ghash_ctx ghash_ctx;
75 union {
76 struct ahash_request ahreq;
77 struct ablkcipher_request abreq;
78 } u;
79};
80
81struct crypto_gcm_setkey_result {
82 int err;
83 struct completion completion;
84};
85
86static struct {
87 u8 buf[16];
88 struct scatterlist sg;
89} *gcm_zeroes;
90
91static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
92
93static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
94 struct aead_request *req)
95{
96 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
97
98 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
99}
100
101static void crypto_gcm_setkey_done(struct crypto_async_request *req, int err)
102{
103 struct crypto_gcm_setkey_result *result = req->data;
104
105 if (err == -EINPROGRESS)
106 return;
107
108 result->err = err;
109 complete(&result->completion);
110}
111
112static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
113 unsigned int keylen)
114{
115 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
116 struct crypto_ahash *ghash = ctx->ghash;
117 struct crypto_ablkcipher *ctr = ctx->ctr;
118 struct {
119 be128 hash;
120 u8 iv[8];
121
122 struct crypto_gcm_setkey_result result;
123
124 struct scatterlist sg[1];
125 struct ablkcipher_request req;
126 } *data;
127 int err;
128
129 crypto_ablkcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
130 crypto_ablkcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
131 CRYPTO_TFM_REQ_MASK);
132 err = crypto_ablkcipher_setkey(ctr, key, keylen);
133 crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) &
134 CRYPTO_TFM_RES_MASK);
135 if (err)
136 return err;
137
138 data = kzalloc(sizeof(*data) + crypto_ablkcipher_reqsize(ctr),
139 GFP_KERNEL);
140 if (!data)
141 return -ENOMEM;
142
143 init_completion(&data->result.completion);
144 sg_init_one(data->sg, &data->hash, sizeof(data->hash));
145 ablkcipher_request_set_tfm(&data->req, ctr);
146 ablkcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
147 CRYPTO_TFM_REQ_MAY_BACKLOG,
148 crypto_gcm_setkey_done,
149 &data->result);
150 ablkcipher_request_set_crypt(&data->req, data->sg, data->sg,
151 sizeof(data->hash), data->iv);
152
153 err = crypto_ablkcipher_encrypt(&data->req);
154 if (err == -EINPROGRESS || err == -EBUSY) {
155 err = wait_for_completion_interruptible(
156 &data->result.completion);
157 if (!err)
158 err = data->result.err;
159 }
160
161 if (err)
162 goto out;
163
164 crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
165 crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
166 CRYPTO_TFM_REQ_MASK);
167 err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
168 crypto_aead_set_flags(aead, crypto_ahash_get_flags(ghash) &
169 CRYPTO_TFM_RES_MASK);
170
171out:
172 kzfree(data);
173 return err;
174}
175
176static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
177 unsigned int authsize)
178{
179 switch (authsize) {
180 case 4:
181 case 8:
182 case 12:
183 case 13:
184 case 14:
185 case 15:
186 case 16:
187 break;
188 default:
189 return -EINVAL;
190 }
191
192 return 0;
193}
194
195static void crypto_gcm_init_common(struct aead_request *req)
196{
197 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
198 __be32 counter = cpu_to_be32(1);
199 struct scatterlist *sg;
200
201 memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
202 memcpy(pctx->iv, req->iv, 12);
203 memcpy(pctx->iv + 12, &counter, 4);
204
205 sg_init_table(pctx->src, 3);
206 sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
207 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
208 if (sg != pctx->src + 1)
209 sg_chain(pctx->src, 2, sg);
210
211 if (req->src != req->dst) {
212 sg_init_table(pctx->dst, 3);
213 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
214 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
215 if (sg != pctx->dst + 1)
216 sg_chain(pctx->dst, 2, sg);
217 }
218}
219
220static void crypto_gcm_init_crypt(struct aead_request *req,
221 unsigned int cryptlen)
222{
223 struct crypto_aead *aead = crypto_aead_reqtfm(req);
224 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
225 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
226 struct ablkcipher_request *ablk_req = &pctx->u.abreq;
227 struct scatterlist *dst;
228
229 dst = req->src == req->dst ? pctx->src : pctx->dst;
230
231 ablkcipher_request_set_tfm(ablk_req, ctx->ctr);
232 ablkcipher_request_set_crypt(ablk_req, pctx->src, dst,
233 cryptlen + sizeof(pctx->auth_tag),
234 pctx->iv);
235}
236
237static inline unsigned int gcm_remain(unsigned int len)
238{
239 len &= 0xfU;
240 return len ? 16 - len : 0;
241}
242
243static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
244
245static int gcm_hash_update(struct aead_request *req,
246 crypto_completion_t compl,
247 struct scatterlist *src,
248 unsigned int len, u32 flags)
249{
250 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
251 struct ahash_request *ahreq = &pctx->u.ahreq;
252
253 ahash_request_set_callback(ahreq, flags, compl, req);
254 ahash_request_set_crypt(ahreq, src, NULL, len);
255
256 return crypto_ahash_update(ahreq);
257}
258
259static int gcm_hash_remain(struct aead_request *req,
260 unsigned int remain,
261 crypto_completion_t compl, u32 flags)
262{
263 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
264}
265
266static int gcm_hash_len(struct aead_request *req, u32 flags)
267{
268 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
269 struct ahash_request *ahreq = &pctx->u.ahreq;
270 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
271 u128 lengths;
272
273 lengths.a = cpu_to_be64(req->assoclen * 8);
274 lengths.b = cpu_to_be64(gctx->cryptlen * 8);
275 memcpy(pctx->iauth_tag, &lengths, 16);
276 sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
277 ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
278 ahash_request_set_crypt(ahreq, &pctx->sg,
279 pctx->iauth_tag, sizeof(lengths));
280
281 return crypto_ahash_finup(ahreq);
282}
283
284static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
285{
286 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
287 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
288
289 return gctx->complete(req, flags);
290}
291
292static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
293{
294 struct aead_request *req = areq->data;
295
296 if (err)
297 goto out;
298
299 err = gcm_hash_len_continue(req, 0);
300 if (err == -EINPROGRESS)
301 return;
302
303out:
304 aead_request_complete(req, err);
305}
306
307static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
308{
309 return gcm_hash_len(req, flags) ?:
310 gcm_hash_len_continue(req, flags);
311}
312
313static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
314 int err)
315{
316 struct aead_request *req = areq->data;
317
318 if (err)
319 goto out;
320
321 err = gcm_hash_crypt_remain_continue(req, 0);
322 if (err == -EINPROGRESS)
323 return;
324
325out:
326 aead_request_complete(req, err);
327}
328
329static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
330{
331 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
332 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
333 unsigned int remain;
334
335 remain = gcm_remain(gctx->cryptlen);
336 if (remain)
337 return gcm_hash_remain(req, remain,
338 gcm_hash_crypt_remain_done, flags) ?:
339 gcm_hash_crypt_remain_continue(req, flags);
340
341 return gcm_hash_crypt_remain_continue(req, flags);
342}
343
344static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
345{
346 struct aead_request *req = areq->data;
347
348 if (err)
349 goto out;
350
351 err = gcm_hash_crypt_continue(req, 0);
352 if (err == -EINPROGRESS)
353 return;
354
355out:
356 aead_request_complete(req, err);
357}
358
359static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
360{
361 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
362 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
363
364 if (gctx->cryptlen)
365 return gcm_hash_update(req, gcm_hash_crypt_done,
366 gctx->src, gctx->cryptlen, flags) ?:
367 gcm_hash_crypt_continue(req, flags);
368
369 return gcm_hash_crypt_remain_continue(req, flags);
370}
371
372static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
373 int err)
374{
375 struct aead_request *req = areq->data;
376
377 if (err)
378 goto out;
379
380 err = gcm_hash_assoc_remain_continue(req, 0);
381 if (err == -EINPROGRESS)
382 return;
383
384out:
385 aead_request_complete(req, err);
386}
387
388static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
389{
390 unsigned int remain;
391
392 remain = gcm_remain(req->assoclen);
393 if (remain)
394 return gcm_hash_remain(req, remain,
395 gcm_hash_assoc_remain_done, flags) ?:
396 gcm_hash_assoc_remain_continue(req, flags);
397
398 return gcm_hash_assoc_remain_continue(req, flags);
399}
400
401static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
402{
403 struct aead_request *req = areq->data;
404
405 if (err)
406 goto out;
407
408 err = gcm_hash_assoc_continue(req, 0);
409 if (err == -EINPROGRESS)
410 return;
411
412out:
413 aead_request_complete(req, err);
414}
415
416static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
417{
418 if (req->assoclen)
419 return gcm_hash_update(req, gcm_hash_assoc_done,
420 req->src, req->assoclen, flags) ?:
421 gcm_hash_assoc_continue(req, flags);
422
423 return gcm_hash_assoc_remain_continue(req, flags);
424}
425
426static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
427{
428 struct aead_request *req = areq->data;
429
430 if (err)
431 goto out;
432
433 err = gcm_hash_init_continue(req, 0);
434 if (err == -EINPROGRESS)
435 return;
436
437out:
438 aead_request_complete(req, err);
439}
440
441static int gcm_hash(struct aead_request *req, u32 flags)
442{
443 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
444 struct ahash_request *ahreq = &pctx->u.ahreq;
445 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
446
447 ahash_request_set_tfm(ahreq, ctx->ghash);
448
449 ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
450 return crypto_ahash_init(ahreq) ?:
451 gcm_hash_init_continue(req, flags);
452}
453
454static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
455{
456 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
457 struct crypto_aead *aead = crypto_aead_reqtfm(req);
458 u8 *auth_tag = pctx->auth_tag;
459
460 crypto_xor(auth_tag, pctx->iauth_tag, 16);
461 scatterwalk_map_and_copy(auth_tag, req->dst,
462 req->assoclen + req->cryptlen,
463 crypto_aead_authsize(aead), 1);
464 return 0;
465}
466
467static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
468{
469 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
470 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
471
472 gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
473 gctx->cryptlen = req->cryptlen;
474 gctx->complete = gcm_enc_copy_hash;
475
476 return gcm_hash(req, flags);
477}
478
479static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
480{
481 struct aead_request *req = areq->data;
482
483 if (err)
484 goto out;
485
486 err = gcm_encrypt_continue(req, 0);
487 if (err == -EINPROGRESS)
488 return;
489
490out:
491 aead_request_complete(req, err);
492}
493
494static int crypto_gcm_encrypt(struct aead_request *req)
495{
496 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
497 struct ablkcipher_request *abreq = &pctx->u.abreq;
498 u32 flags = aead_request_flags(req);
499
500 crypto_gcm_init_common(req);
501 crypto_gcm_init_crypt(req, req->cryptlen);
502 ablkcipher_request_set_callback(abreq, flags, gcm_encrypt_done, req);
503
504 return crypto_ablkcipher_encrypt(abreq) ?:
505 gcm_encrypt_continue(req, flags);
506}
507
508static int crypto_gcm_verify(struct aead_request *req)
509{
510 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
511 struct crypto_aead *aead = crypto_aead_reqtfm(req);
512 u8 *auth_tag = pctx->auth_tag;
513 u8 *iauth_tag = pctx->iauth_tag;
514 unsigned int authsize = crypto_aead_authsize(aead);
515 unsigned int cryptlen = req->cryptlen - authsize;
516
517 crypto_xor(auth_tag, iauth_tag, 16);
518 scatterwalk_map_and_copy(iauth_tag, req->src,
519 req->assoclen + cryptlen, authsize, 0);
520 return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
521}
522
523static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
524{
525 struct aead_request *req = areq->data;
526
527 if (!err)
528 err = crypto_gcm_verify(req);
529
530 aead_request_complete(req, err);
531}
532
533static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
534{
535 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
536 struct ablkcipher_request *abreq = &pctx->u.abreq;
537 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
538
539 crypto_gcm_init_crypt(req, gctx->cryptlen);
540 ablkcipher_request_set_callback(abreq, flags, gcm_decrypt_done, req);
541 return crypto_ablkcipher_decrypt(abreq) ?: crypto_gcm_verify(req);
542}
543
544static int crypto_gcm_decrypt(struct aead_request *req)
545{
546 struct crypto_aead *aead = crypto_aead_reqtfm(req);
547 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
548 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
549 unsigned int authsize = crypto_aead_authsize(aead);
550 unsigned int cryptlen = req->cryptlen;
551 u32 flags = aead_request_flags(req);
552
553 cryptlen -= authsize;
554
555 crypto_gcm_init_common(req);
556
557 gctx->src = sg_next(pctx->src);
558 gctx->cryptlen = cryptlen;
559 gctx->complete = gcm_dec_hash_continue;
560
561 return gcm_hash(req, flags);
562}
563
564static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
565{
566 struct aead_instance *inst = aead_alg_instance(tfm);
567 struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
568 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
569 struct crypto_ablkcipher *ctr;
570 struct crypto_ahash *ghash;
571 unsigned long align;
572 int err;
573
574 ghash = crypto_spawn_ahash(&ictx->ghash);
575 if (IS_ERR(ghash))
576 return PTR_ERR(ghash);
577
578 ctr = crypto_spawn_skcipher(&ictx->ctr);
579 err = PTR_ERR(ctr);
580 if (IS_ERR(ctr))
581 goto err_free_hash;
582
583 ctx->ctr = ctr;
584 ctx->ghash = ghash;
585
586 align = crypto_aead_alignmask(tfm);
587 align &= ~(crypto_tfm_ctx_alignment() - 1);
588 crypto_aead_set_reqsize(tfm,
589 align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
590 max(sizeof(struct ablkcipher_request) +
591 crypto_ablkcipher_reqsize(ctr),
592 sizeof(struct ahash_request) +
593 crypto_ahash_reqsize(ghash)));
594
595 return 0;
596
597err_free_hash:
598 crypto_free_ahash(ghash);
599 return err;
600}
601
602static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
603{
604 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
605
606 crypto_free_ahash(ctx->ghash);
607 crypto_free_ablkcipher(ctx->ctr);
608}
609
610static void crypto_gcm_free(struct aead_instance *inst)
611{
612 struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
613
614 crypto_drop_skcipher(&ctx->ctr);
615 crypto_drop_ahash(&ctx->ghash);
616 kfree(inst);
617}
618
619static int crypto_gcm_create_common(struct crypto_template *tmpl,
620 struct rtattr **tb,
621 const char *full_name,
622 const char *ctr_name,
623 const char *ghash_name)
624{
625 struct crypto_attr_type *algt;
626 struct aead_instance *inst;
627 struct crypto_alg *ctr;
628 struct crypto_alg *ghash_alg;
629 struct hash_alg_common *ghash;
630 struct gcm_instance_ctx *ctx;
631 int err;
632
633 algt = crypto_get_attr_type(tb);
634 if (IS_ERR(algt))
635 return PTR_ERR(algt);
636
637 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
638 return -EINVAL;
639
640 ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
641 CRYPTO_ALG_TYPE_HASH,
642 CRYPTO_ALG_TYPE_AHASH_MASK);
643 if (IS_ERR(ghash_alg))
644 return PTR_ERR(ghash_alg);
645
646 ghash = __crypto_hash_alg_common(ghash_alg);
647
648 err = -ENOMEM;
649 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
650 if (!inst)
651 goto out_put_ghash;
652
653 ctx = aead_instance_ctx(inst);
654 err = crypto_init_ahash_spawn(&ctx->ghash, ghash,
655 aead_crypto_instance(inst));
656 if (err)
657 goto err_free_inst;
658
659 err = -EINVAL;
660 if (ghash->digestsize != 16)
661 goto err_drop_ghash;
662
663 crypto_set_skcipher_spawn(&ctx->ctr, aead_crypto_instance(inst));
664 err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
665 crypto_requires_sync(algt->type,
666 algt->mask));
667 if (err)
668 goto err_drop_ghash;
669
670 ctr = crypto_skcipher_spawn_alg(&ctx->ctr);
671
672 /* We only support 16-byte blocks. */
673 if (ctr->cra_ablkcipher.ivsize != 16)
674 goto out_put_ctr;
675
676 /* Not a stream cipher? */
677 err = -EINVAL;
678 if (ctr->cra_blocksize != 1)
679 goto out_put_ctr;
680
681 err = -ENAMETOOLONG;
682 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
683 "gcm_base(%s,%s)", ctr->cra_driver_name,
684 ghash_alg->cra_driver_name) >=
685 CRYPTO_MAX_ALG_NAME)
686 goto out_put_ctr;
687
688 memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
689
690 inst->alg.base.cra_flags = (ghash->base.cra_flags | ctr->cra_flags) &
691 CRYPTO_ALG_ASYNC;
692 inst->alg.base.cra_priority = (ghash->base.cra_priority +
693 ctr->cra_priority) / 2;
694 inst->alg.base.cra_blocksize = 1;
695 inst->alg.base.cra_alignmask = ghash->base.cra_alignmask |
696 ctr->cra_alignmask;
697 inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
698 inst->alg.ivsize = 12;
699 inst->alg.maxauthsize = 16;
700 inst->alg.init = crypto_gcm_init_tfm;
701 inst->alg.exit = crypto_gcm_exit_tfm;
702 inst->alg.setkey = crypto_gcm_setkey;
703 inst->alg.setauthsize = crypto_gcm_setauthsize;
704 inst->alg.encrypt = crypto_gcm_encrypt;
705 inst->alg.decrypt = crypto_gcm_decrypt;
706
707 inst->free = crypto_gcm_free;
708
709 err = aead_register_instance(tmpl, inst);
710 if (err)
711 goto out_put_ctr;
712
713out_put_ghash:
714 crypto_mod_put(ghash_alg);
715 return err;
716
717out_put_ctr:
718 crypto_drop_skcipher(&ctx->ctr);
719err_drop_ghash:
720 crypto_drop_ahash(&ctx->ghash);
721err_free_inst:
722 kfree(inst);
723 goto out_put_ghash;
724}
725
726static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
727{
728 const char *cipher_name;
729 char ctr_name[CRYPTO_MAX_ALG_NAME];
730 char full_name[CRYPTO_MAX_ALG_NAME];
731
732 cipher_name = crypto_attr_alg_name(tb[1]);
733 if (IS_ERR(cipher_name))
734 return PTR_ERR(cipher_name);
735
736 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
737 CRYPTO_MAX_ALG_NAME)
738 return -ENAMETOOLONG;
739
740 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >=
741 CRYPTO_MAX_ALG_NAME)
742 return -ENAMETOOLONG;
743
744 return crypto_gcm_create_common(tmpl, tb, full_name,
745 ctr_name, "ghash");
746}
747
748static struct crypto_template crypto_gcm_tmpl = {
749 .name = "gcm",
750 .create = crypto_gcm_create,
751 .module = THIS_MODULE,
752};
753
754static int crypto_gcm_base_create(struct crypto_template *tmpl,
755 struct rtattr **tb)
756{
757 const char *ctr_name;
758 const char *ghash_name;
759 char full_name[CRYPTO_MAX_ALG_NAME];
760
761 ctr_name = crypto_attr_alg_name(tb[1]);
762 if (IS_ERR(ctr_name))
763 return PTR_ERR(ctr_name);
764
765 ghash_name = crypto_attr_alg_name(tb[2]);
766 if (IS_ERR(ghash_name))
767 return PTR_ERR(ghash_name);
768
769 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)",
770 ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME)
771 return -ENAMETOOLONG;
772
773 return crypto_gcm_create_common(tmpl, tb, full_name,
774 ctr_name, ghash_name);
775}
776
777static struct crypto_template crypto_gcm_base_tmpl = {
778 .name = "gcm_base",
779 .create = crypto_gcm_base_create,
780 .module = THIS_MODULE,
781};
782
783static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
784 unsigned int keylen)
785{
786 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
787 struct crypto_aead *child = ctx->child;
788 int err;
789
790 if (keylen < 4)
791 return -EINVAL;
792
793 keylen -= 4;
794 memcpy(ctx->nonce, key + keylen, 4);
795
796 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
797 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
798 CRYPTO_TFM_REQ_MASK);
799 err = crypto_aead_setkey(child, key, keylen);
800 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
801 CRYPTO_TFM_RES_MASK);
802
803 return err;
804}
805
806static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
807 unsigned int authsize)
808{
809 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
810
811 switch (authsize) {
812 case 8:
813 case 12:
814 case 16:
815 break;
816 default:
817 return -EINVAL;
818 }
819
820 return crypto_aead_setauthsize(ctx->child, authsize);
821}
822
823static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
824{
825 struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req);
826 struct crypto_aead *aead = crypto_aead_reqtfm(req);
827 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
828 struct aead_request *subreq = &rctx->subreq;
829 struct crypto_aead *child = ctx->child;
830 struct scatterlist *sg;
831 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
832 crypto_aead_alignmask(child) + 1);
833
834 scatterwalk_map_and_copy(iv + 12, req->src, 0, req->assoclen - 8, 0);
835
836 memcpy(iv, ctx->nonce, 4);
837 memcpy(iv + 4, req->iv, 8);
838
839 sg_init_table(rctx->src, 3);
840 sg_set_buf(rctx->src, iv + 12, req->assoclen - 8);
841 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
842 if (sg != rctx->src + 1)
843 sg_chain(rctx->src, 2, sg);
844
845 if (req->src != req->dst) {
846 sg_init_table(rctx->dst, 3);
847 sg_set_buf(rctx->dst, iv + 12, req->assoclen - 8);
848 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
849 if (sg != rctx->dst + 1)
850 sg_chain(rctx->dst, 2, sg);
851 }
852
853 aead_request_set_tfm(subreq, child);
854 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
855 req->base.data);
856 aead_request_set_crypt(subreq, rctx->src,
857 req->src == req->dst ? rctx->src : rctx->dst,
858 req->cryptlen, iv);
859 aead_request_set_ad(subreq, req->assoclen - 8);
860
861 return subreq;
862}
863
864static int crypto_rfc4106_encrypt(struct aead_request *req)
865{
866 if (req->assoclen != 16 && req->assoclen != 20)
867 return -EINVAL;
868
869 req = crypto_rfc4106_crypt(req);
870
871 return crypto_aead_encrypt(req);
872}
873
874static int crypto_rfc4106_decrypt(struct aead_request *req)
875{
876 if (req->assoclen != 16 && req->assoclen != 20)
877 return -EINVAL;
878
879 req = crypto_rfc4106_crypt(req);
880
881 return crypto_aead_decrypt(req);
882}
883
884static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
885{
886 struct aead_instance *inst = aead_alg_instance(tfm);
887 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
888 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
889 struct crypto_aead *aead;
890 unsigned long align;
891
892 aead = crypto_spawn_aead(spawn);
893 if (IS_ERR(aead))
894 return PTR_ERR(aead);
895
896 ctx->child = aead;
897
898 align = crypto_aead_alignmask(aead);
899 align &= ~(crypto_tfm_ctx_alignment() - 1);
900 crypto_aead_set_reqsize(
901 tfm,
902 sizeof(struct crypto_rfc4106_req_ctx) +
903 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
904 align + 24);
905
906 return 0;
907}
908
909static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
910{
911 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
912
913 crypto_free_aead(ctx->child);
914}
915
916static void crypto_rfc4106_free(struct aead_instance *inst)
917{
918 crypto_drop_aead(aead_instance_ctx(inst));
919 kfree(inst);
920}
921
922static int crypto_rfc4106_create(struct crypto_template *tmpl,
923 struct rtattr **tb)
924{
925 struct crypto_attr_type *algt;
926 struct aead_instance *inst;
927 struct crypto_aead_spawn *spawn;
928 struct aead_alg *alg;
929 const char *ccm_name;
930 int err;
931
932 algt = crypto_get_attr_type(tb);
933 if (IS_ERR(algt))
934 return PTR_ERR(algt);
935
936 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
937 return -EINVAL;
938
939 ccm_name = crypto_attr_alg_name(tb[1]);
940 if (IS_ERR(ccm_name))
941 return PTR_ERR(ccm_name);
942
943 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
944 if (!inst)
945 return -ENOMEM;
946
947 spawn = aead_instance_ctx(inst);
948 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
949 err = crypto_grab_aead(spawn, ccm_name, 0,
950 crypto_requires_sync(algt->type, algt->mask));
951 if (err)
952 goto out_free_inst;
953
954 alg = crypto_spawn_aead_alg(spawn);
955
956 err = -EINVAL;
957
958 /* Underlying IV size must be 12. */
959 if (crypto_aead_alg_ivsize(alg) != 12)
960 goto out_drop_alg;
961
962 /* Not a stream cipher? */
963 if (alg->base.cra_blocksize != 1)
964 goto out_drop_alg;
965
966 err = -ENAMETOOLONG;
967 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
968 "rfc4106(%s)", alg->base.cra_name) >=
969 CRYPTO_MAX_ALG_NAME ||
970 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
971 "rfc4106(%s)", alg->base.cra_driver_name) >=
972 CRYPTO_MAX_ALG_NAME)
973 goto out_drop_alg;
974
975 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
976 inst->alg.base.cra_priority = alg->base.cra_priority;
977 inst->alg.base.cra_blocksize = 1;
978 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
979
980 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
981
982 inst->alg.ivsize = 8;
983 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
984
985 inst->alg.init = crypto_rfc4106_init_tfm;
986 inst->alg.exit = crypto_rfc4106_exit_tfm;
987
988 inst->alg.setkey = crypto_rfc4106_setkey;
989 inst->alg.setauthsize = crypto_rfc4106_setauthsize;
990 inst->alg.encrypt = crypto_rfc4106_encrypt;
991 inst->alg.decrypt = crypto_rfc4106_decrypt;
992
993 inst->free = crypto_rfc4106_free;
994
995 err = aead_register_instance(tmpl, inst);
996 if (err)
997 goto out_drop_alg;
998
999out:
1000 return err;
1001
1002out_drop_alg:
1003 crypto_drop_aead(spawn);
1004out_free_inst:
1005 kfree(inst);
1006 goto out;
1007}
1008
1009static struct crypto_template crypto_rfc4106_tmpl = {
1010 .name = "rfc4106",
1011 .create = crypto_rfc4106_create,
1012 .module = THIS_MODULE,
1013};
1014
1015static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
1016 unsigned int keylen)
1017{
1018 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
1019 struct crypto_aead *child = ctx->child;
1020 int err;
1021
1022 if (keylen < 4)
1023 return -EINVAL;
1024
1025 keylen -= 4;
1026 memcpy(ctx->nonce, key + keylen, 4);
1027
1028 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
1029 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
1030 CRYPTO_TFM_REQ_MASK);
1031 err = crypto_aead_setkey(child, key, keylen);
1032 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
1033 CRYPTO_TFM_RES_MASK);
1034
1035 return err;
1036}
1037
1038static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
1039 unsigned int authsize)
1040{
1041 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
1042
1043 if (authsize != 16)
1044 return -EINVAL;
1045
1046 return crypto_aead_setauthsize(ctx->child, authsize);
1047}
1048
1049static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
1050{
1051 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1052 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1053 struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
1054 struct aead_request *subreq = &rctx->subreq;
1055 unsigned int authsize = crypto_aead_authsize(aead);
1056 u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
1057 crypto_aead_alignmask(ctx->child) + 1);
1058 int err;
1059
1060 if (req->src != req->dst) {
1061 err = crypto_rfc4543_copy_src_to_dst(req, enc);
1062 if (err)
1063 return err;
1064 }
1065
1066 memcpy(iv, ctx->nonce, 4);
1067 memcpy(iv + 4, req->iv, 8);
1068
1069 aead_request_set_tfm(subreq, ctx->child);
1070 aead_request_set_callback(subreq, req->base.flags,
1071 req->base.complete, req->base.data);
1072 aead_request_set_crypt(subreq, req->src, req->dst,
1073 enc ? 0 : authsize, iv);
1074 aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
1075 subreq->cryptlen);
1076
1077 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
1078}
1079
1080static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
1081{
1082 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1083 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1084 unsigned int authsize = crypto_aead_authsize(aead);
1085 unsigned int nbytes = req->assoclen + req->cryptlen -
1086 (enc ? 0 : authsize);
1087 struct blkcipher_desc desc = {
1088 .tfm = ctx->null,
1089 };
1090
1091 return crypto_blkcipher_encrypt(&desc, req->dst, req->src, nbytes);
1092}
1093
1094static int crypto_rfc4543_encrypt(struct aead_request *req)
1095{
1096 return crypto_rfc4543_crypt(req, true);
1097}
1098
1099static int crypto_rfc4543_decrypt(struct aead_request *req)
1100{
1101 return crypto_rfc4543_crypt(req, false);
1102}
1103
1104static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
1105{
1106 struct aead_instance *inst = aead_alg_instance(tfm);
1107 struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst);
1108 struct crypto_aead_spawn *spawn = &ictx->aead;
1109 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1110 struct crypto_aead *aead;
1111 struct crypto_blkcipher *null;
1112 unsigned long align;
1113 int err = 0;
1114
1115 aead = crypto_spawn_aead(spawn);
1116 if (IS_ERR(aead))
1117 return PTR_ERR(aead);
1118
1119 null = crypto_get_default_null_skcipher();
1120 err = PTR_ERR(null);
1121 if (IS_ERR(null))
1122 goto err_free_aead;
1123
1124 ctx->child = aead;
1125 ctx->null = null;
1126
1127 align = crypto_aead_alignmask(aead);
1128 align &= ~(crypto_tfm_ctx_alignment() - 1);
1129 crypto_aead_set_reqsize(
1130 tfm,
1131 sizeof(struct crypto_rfc4543_req_ctx) +
1132 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
1133 align + 12);
1134
1135 return 0;
1136
1137err_free_aead:
1138 crypto_free_aead(aead);
1139 return err;
1140}
1141
1142static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
1143{
1144 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1145
1146 crypto_free_aead(ctx->child);
1147 crypto_put_default_null_skcipher();
1148}
1149
1150static void crypto_rfc4543_free(struct aead_instance *inst)
1151{
1152 struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst);
1153
1154 crypto_drop_aead(&ctx->aead);
1155
1156 kfree(inst);
1157}
1158
1159static int crypto_rfc4543_create(struct crypto_template *tmpl,
1160 struct rtattr **tb)
1161{
1162 struct crypto_attr_type *algt;
1163 struct aead_instance *inst;
1164 struct crypto_aead_spawn *spawn;
1165 struct aead_alg *alg;
1166 struct crypto_rfc4543_instance_ctx *ctx;
1167 const char *ccm_name;
1168 int err;
1169
1170 algt = crypto_get_attr_type(tb);
1171 if (IS_ERR(algt))
1172 return PTR_ERR(algt);
1173
1174 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
1175 return -EINVAL;
1176
1177 ccm_name = crypto_attr_alg_name(tb[1]);
1178 if (IS_ERR(ccm_name))
1179 return PTR_ERR(ccm_name);
1180
1181 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1182 if (!inst)
1183 return -ENOMEM;
1184
1185 ctx = aead_instance_ctx(inst);
1186 spawn = &ctx->aead;
1187 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
1188 err = crypto_grab_aead(spawn, ccm_name, 0,
1189 crypto_requires_sync(algt->type, algt->mask));
1190 if (err)
1191 goto out_free_inst;
1192
1193 alg = crypto_spawn_aead_alg(spawn);
1194
1195 err = -EINVAL;
1196
1197 /* Underlying IV size must be 12. */
1198 if (crypto_aead_alg_ivsize(alg) != 12)
1199 goto out_drop_alg;
1200
1201 /* Not a stream cipher? */
1202 if (alg->base.cra_blocksize != 1)
1203 goto out_drop_alg;
1204
1205 err = -ENAMETOOLONG;
1206 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
1207 "rfc4543(%s)", alg->base.cra_name) >=
1208 CRYPTO_MAX_ALG_NAME ||
1209 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1210 "rfc4543(%s)", alg->base.cra_driver_name) >=
1211 CRYPTO_MAX_ALG_NAME)
1212 goto out_drop_alg;
1213
1214 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
1215 inst->alg.base.cra_priority = alg->base.cra_priority;
1216 inst->alg.base.cra_blocksize = 1;
1217 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
1218
1219 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
1220
1221 inst->alg.ivsize = 8;
1222 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
1223
1224 inst->alg.init = crypto_rfc4543_init_tfm;
1225 inst->alg.exit = crypto_rfc4543_exit_tfm;
1226
1227 inst->alg.setkey = crypto_rfc4543_setkey;
1228 inst->alg.setauthsize = crypto_rfc4543_setauthsize;
1229 inst->alg.encrypt = crypto_rfc4543_encrypt;
1230 inst->alg.decrypt = crypto_rfc4543_decrypt;
1231
1232 inst->free = crypto_rfc4543_free,
1233
1234 err = aead_register_instance(tmpl, inst);
1235 if (err)
1236 goto out_drop_alg;
1237
1238out:
1239 return err;
1240
1241out_drop_alg:
1242 crypto_drop_aead(spawn);
1243out_free_inst:
1244 kfree(inst);
1245 goto out;
1246}
1247
1248static struct crypto_template crypto_rfc4543_tmpl = {
1249 .name = "rfc4543",
1250 .create = crypto_rfc4543_create,
1251 .module = THIS_MODULE,
1252};
1253
1254static int __init crypto_gcm_module_init(void)
1255{
1256 int err;
1257
1258 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
1259 if (!gcm_zeroes)
1260 return -ENOMEM;
1261
1262 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
1263
1264 err = crypto_register_template(&crypto_gcm_base_tmpl);
1265 if (err)
1266 goto out;
1267
1268 err = crypto_register_template(&crypto_gcm_tmpl);
1269 if (err)
1270 goto out_undo_base;
1271
1272 err = crypto_register_template(&crypto_rfc4106_tmpl);
1273 if (err)
1274 goto out_undo_gcm;
1275
1276 err = crypto_register_template(&crypto_rfc4543_tmpl);
1277 if (err)
1278 goto out_undo_rfc4106;
1279
1280 return 0;
1281
1282out_undo_rfc4106:
1283 crypto_unregister_template(&crypto_rfc4106_tmpl);
1284out_undo_gcm:
1285 crypto_unregister_template(&crypto_gcm_tmpl);
1286out_undo_base:
1287 crypto_unregister_template(&crypto_gcm_base_tmpl);
1288out:
1289 kfree(gcm_zeroes);
1290 return err;
1291}
1292
1293static void __exit crypto_gcm_module_exit(void)
1294{
1295 kfree(gcm_zeroes);
1296 crypto_unregister_template(&crypto_rfc4543_tmpl);
1297 crypto_unregister_template(&crypto_rfc4106_tmpl);
1298 crypto_unregister_template(&crypto_gcm_tmpl);
1299 crypto_unregister_template(&crypto_gcm_base_tmpl);
1300}
1301
1302module_init(crypto_gcm_module_init);
1303module_exit(crypto_gcm_module_exit);
1304
1305MODULE_LICENSE("GPL");
1306MODULE_DESCRIPTION("Galois/Counter Mode");
1307MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1308MODULE_ALIAS_CRYPTO("gcm_base");
1309MODULE_ALIAS_CRYPTO("rfc4106");
1310MODULE_ALIAS_CRYPTO("rfc4543");
1311MODULE_ALIAS_CRYPTO("gcm");
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
26struct gcm_instance_ctx {
27 struct crypto_skcipher_spawn ctr;
28 struct crypto_ahash_spawn ghash;
29};
30
31struct crypto_gcm_ctx {
32 struct crypto_skcipher *ctr;
33 struct crypto_ahash *ghash;
34};
35
36struct crypto_rfc4106_ctx {
37 struct crypto_aead *child;
38 u8 nonce[4];
39};
40
41struct crypto_rfc4106_req_ctx {
42 struct scatterlist src[3];
43 struct scatterlist dst[3];
44 struct aead_request subreq;
45};
46
47struct crypto_rfc4543_instance_ctx {
48 struct crypto_aead_spawn aead;
49};
50
51struct crypto_rfc4543_ctx {
52 struct crypto_aead *child;
53 struct crypto_skcipher *null;
54 u8 nonce[4];
55};
56
57struct crypto_rfc4543_req_ctx {
58 struct aead_request subreq;
59};
60
61struct crypto_gcm_ghash_ctx {
62 unsigned int cryptlen;
63 struct scatterlist *src;
64 int (*complete)(struct aead_request *req, u32 flags);
65};
66
67struct crypto_gcm_req_priv_ctx {
68 u8 iv[16];
69 u8 auth_tag[16];
70 u8 iauth_tag[16];
71 struct scatterlist src[3];
72 struct scatterlist dst[3];
73 struct scatterlist sg;
74 struct crypto_gcm_ghash_ctx ghash_ctx;
75 union {
76 struct ahash_request ahreq;
77 struct skcipher_request skreq;
78 } u;
79};
80
81struct crypto_gcm_setkey_result {
82 int err;
83 struct completion completion;
84};
85
86static struct {
87 u8 buf[16];
88 struct scatterlist sg;
89} *gcm_zeroes;
90
91static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
92
93static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
94 struct aead_request *req)
95{
96 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
97
98 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
99}
100
101static void crypto_gcm_setkey_done(struct crypto_async_request *req, int err)
102{
103 struct crypto_gcm_setkey_result *result = req->data;
104
105 if (err == -EINPROGRESS)
106 return;
107
108 result->err = err;
109 complete(&result->completion);
110}
111
112static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
113 unsigned int keylen)
114{
115 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
116 struct crypto_ahash *ghash = ctx->ghash;
117 struct crypto_skcipher *ctr = ctx->ctr;
118 struct {
119 be128 hash;
120 u8 iv[16];
121
122 struct crypto_gcm_setkey_result result;
123
124 struct scatterlist sg[1];
125 struct skcipher_request req;
126 } *data;
127 int err;
128
129 crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
130 crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
131 CRYPTO_TFM_REQ_MASK);
132 err = crypto_skcipher_setkey(ctr, key, keylen);
133 crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) &
134 CRYPTO_TFM_RES_MASK);
135 if (err)
136 return err;
137
138 data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr),
139 GFP_KERNEL);
140 if (!data)
141 return -ENOMEM;
142
143 init_completion(&data->result.completion);
144 sg_init_one(data->sg, &data->hash, sizeof(data->hash));
145 skcipher_request_set_tfm(&data->req, ctr);
146 skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
147 CRYPTO_TFM_REQ_MAY_BACKLOG,
148 crypto_gcm_setkey_done,
149 &data->result);
150 skcipher_request_set_crypt(&data->req, data->sg, data->sg,
151 sizeof(data->hash), data->iv);
152
153 err = crypto_skcipher_encrypt(&data->req);
154 if (err == -EINPROGRESS || err == -EBUSY) {
155 err = wait_for_completion_interruptible(
156 &data->result.completion);
157 if (!err)
158 err = data->result.err;
159 }
160
161 if (err)
162 goto out;
163
164 crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
165 crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
166 CRYPTO_TFM_REQ_MASK);
167 err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
168 crypto_aead_set_flags(aead, crypto_ahash_get_flags(ghash) &
169 CRYPTO_TFM_RES_MASK);
170
171out:
172 kzfree(data);
173 return err;
174}
175
176static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
177 unsigned int authsize)
178{
179 switch (authsize) {
180 case 4:
181 case 8:
182 case 12:
183 case 13:
184 case 14:
185 case 15:
186 case 16:
187 break;
188 default:
189 return -EINVAL;
190 }
191
192 return 0;
193}
194
195static void crypto_gcm_init_common(struct aead_request *req)
196{
197 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
198 __be32 counter = cpu_to_be32(1);
199 struct scatterlist *sg;
200
201 memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
202 memcpy(pctx->iv, req->iv, 12);
203 memcpy(pctx->iv + 12, &counter, 4);
204
205 sg_init_table(pctx->src, 3);
206 sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
207 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
208 if (sg != pctx->src + 1)
209 sg_chain(pctx->src, 2, sg);
210
211 if (req->src != req->dst) {
212 sg_init_table(pctx->dst, 3);
213 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
214 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
215 if (sg != pctx->dst + 1)
216 sg_chain(pctx->dst, 2, sg);
217 }
218}
219
220static void crypto_gcm_init_crypt(struct aead_request *req,
221 unsigned int cryptlen)
222{
223 struct crypto_aead *aead = crypto_aead_reqtfm(req);
224 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
225 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
226 struct skcipher_request *skreq = &pctx->u.skreq;
227 struct scatterlist *dst;
228
229 dst = req->src == req->dst ? pctx->src : pctx->dst;
230
231 skcipher_request_set_tfm(skreq, ctx->ctr);
232 skcipher_request_set_crypt(skreq, pctx->src, dst,
233 cryptlen + sizeof(pctx->auth_tag),
234 pctx->iv);
235}
236
237static inline unsigned int gcm_remain(unsigned int len)
238{
239 len &= 0xfU;
240 return len ? 16 - len : 0;
241}
242
243static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
244
245static int gcm_hash_update(struct aead_request *req,
246 crypto_completion_t compl,
247 struct scatterlist *src,
248 unsigned int len, u32 flags)
249{
250 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
251 struct ahash_request *ahreq = &pctx->u.ahreq;
252
253 ahash_request_set_callback(ahreq, flags, compl, req);
254 ahash_request_set_crypt(ahreq, src, NULL, len);
255
256 return crypto_ahash_update(ahreq);
257}
258
259static int gcm_hash_remain(struct aead_request *req,
260 unsigned int remain,
261 crypto_completion_t compl, u32 flags)
262{
263 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
264}
265
266static int gcm_hash_len(struct aead_request *req, u32 flags)
267{
268 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
269 struct ahash_request *ahreq = &pctx->u.ahreq;
270 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
271 u128 lengths;
272
273 lengths.a = cpu_to_be64(req->assoclen * 8);
274 lengths.b = cpu_to_be64(gctx->cryptlen * 8);
275 memcpy(pctx->iauth_tag, &lengths, 16);
276 sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
277 ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
278 ahash_request_set_crypt(ahreq, &pctx->sg,
279 pctx->iauth_tag, sizeof(lengths));
280
281 return crypto_ahash_finup(ahreq);
282}
283
284static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
285{
286 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
287 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
288
289 return gctx->complete(req, flags);
290}
291
292static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
293{
294 struct aead_request *req = areq->data;
295
296 if (err)
297 goto out;
298
299 err = gcm_hash_len_continue(req, 0);
300 if (err == -EINPROGRESS)
301 return;
302
303out:
304 aead_request_complete(req, err);
305}
306
307static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
308{
309 return gcm_hash_len(req, flags) ?:
310 gcm_hash_len_continue(req, flags);
311}
312
313static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
314 int err)
315{
316 struct aead_request *req = areq->data;
317
318 if (err)
319 goto out;
320
321 err = gcm_hash_crypt_remain_continue(req, 0);
322 if (err == -EINPROGRESS)
323 return;
324
325out:
326 aead_request_complete(req, err);
327}
328
329static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
330{
331 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
332 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
333 unsigned int remain;
334
335 remain = gcm_remain(gctx->cryptlen);
336 if (remain)
337 return gcm_hash_remain(req, remain,
338 gcm_hash_crypt_remain_done, flags) ?:
339 gcm_hash_crypt_remain_continue(req, flags);
340
341 return gcm_hash_crypt_remain_continue(req, flags);
342}
343
344static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
345{
346 struct aead_request *req = areq->data;
347
348 if (err)
349 goto out;
350
351 err = gcm_hash_crypt_continue(req, 0);
352 if (err == -EINPROGRESS)
353 return;
354
355out:
356 aead_request_complete(req, err);
357}
358
359static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
360{
361 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
362 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
363
364 if (gctx->cryptlen)
365 return gcm_hash_update(req, gcm_hash_crypt_done,
366 gctx->src, gctx->cryptlen, flags) ?:
367 gcm_hash_crypt_continue(req, flags);
368
369 return gcm_hash_crypt_remain_continue(req, flags);
370}
371
372static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
373 int err)
374{
375 struct aead_request *req = areq->data;
376
377 if (err)
378 goto out;
379
380 err = gcm_hash_assoc_remain_continue(req, 0);
381 if (err == -EINPROGRESS)
382 return;
383
384out:
385 aead_request_complete(req, err);
386}
387
388static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
389{
390 unsigned int remain;
391
392 remain = gcm_remain(req->assoclen);
393 if (remain)
394 return gcm_hash_remain(req, remain,
395 gcm_hash_assoc_remain_done, flags) ?:
396 gcm_hash_assoc_remain_continue(req, flags);
397
398 return gcm_hash_assoc_remain_continue(req, flags);
399}
400
401static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
402{
403 struct aead_request *req = areq->data;
404
405 if (err)
406 goto out;
407
408 err = gcm_hash_assoc_continue(req, 0);
409 if (err == -EINPROGRESS)
410 return;
411
412out:
413 aead_request_complete(req, err);
414}
415
416static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
417{
418 if (req->assoclen)
419 return gcm_hash_update(req, gcm_hash_assoc_done,
420 req->src, req->assoclen, flags) ?:
421 gcm_hash_assoc_continue(req, flags);
422
423 return gcm_hash_assoc_remain_continue(req, flags);
424}
425
426static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
427{
428 struct aead_request *req = areq->data;
429
430 if (err)
431 goto out;
432
433 err = gcm_hash_init_continue(req, 0);
434 if (err == -EINPROGRESS)
435 return;
436
437out:
438 aead_request_complete(req, err);
439}
440
441static int gcm_hash(struct aead_request *req, u32 flags)
442{
443 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
444 struct ahash_request *ahreq = &pctx->u.ahreq;
445 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
446
447 ahash_request_set_tfm(ahreq, ctx->ghash);
448
449 ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
450 return crypto_ahash_init(ahreq) ?:
451 gcm_hash_init_continue(req, flags);
452}
453
454static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
455{
456 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
457 struct crypto_aead *aead = crypto_aead_reqtfm(req);
458 u8 *auth_tag = pctx->auth_tag;
459
460 crypto_xor(auth_tag, pctx->iauth_tag, 16);
461 scatterwalk_map_and_copy(auth_tag, req->dst,
462 req->assoclen + req->cryptlen,
463 crypto_aead_authsize(aead), 1);
464 return 0;
465}
466
467static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
468{
469 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
470 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
471
472 gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
473 gctx->cryptlen = req->cryptlen;
474 gctx->complete = gcm_enc_copy_hash;
475
476 return gcm_hash(req, flags);
477}
478
479static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
480{
481 struct aead_request *req = areq->data;
482
483 if (err)
484 goto out;
485
486 err = gcm_encrypt_continue(req, 0);
487 if (err == -EINPROGRESS)
488 return;
489
490out:
491 aead_request_complete(req, err);
492}
493
494static int crypto_gcm_encrypt(struct aead_request *req)
495{
496 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
497 struct skcipher_request *skreq = &pctx->u.skreq;
498 u32 flags = aead_request_flags(req);
499
500 crypto_gcm_init_common(req);
501 crypto_gcm_init_crypt(req, req->cryptlen);
502 skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req);
503
504 return crypto_skcipher_encrypt(skreq) ?:
505 gcm_encrypt_continue(req, flags);
506}
507
508static int crypto_gcm_verify(struct aead_request *req)
509{
510 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
511 struct crypto_aead *aead = crypto_aead_reqtfm(req);
512 u8 *auth_tag = pctx->auth_tag;
513 u8 *iauth_tag = pctx->iauth_tag;
514 unsigned int authsize = crypto_aead_authsize(aead);
515 unsigned int cryptlen = req->cryptlen - authsize;
516
517 crypto_xor(auth_tag, iauth_tag, 16);
518 scatterwalk_map_and_copy(iauth_tag, req->src,
519 req->assoclen + cryptlen, authsize, 0);
520 return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
521}
522
523static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
524{
525 struct aead_request *req = areq->data;
526
527 if (!err)
528 err = crypto_gcm_verify(req);
529
530 aead_request_complete(req, err);
531}
532
533static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
534{
535 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
536 struct skcipher_request *skreq = &pctx->u.skreq;
537 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
538
539 crypto_gcm_init_crypt(req, gctx->cryptlen);
540 skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req);
541 return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req);
542}
543
544static int crypto_gcm_decrypt(struct aead_request *req)
545{
546 struct crypto_aead *aead = crypto_aead_reqtfm(req);
547 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
548 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
549 unsigned int authsize = crypto_aead_authsize(aead);
550 unsigned int cryptlen = req->cryptlen;
551 u32 flags = aead_request_flags(req);
552
553 cryptlen -= authsize;
554
555 crypto_gcm_init_common(req);
556
557 gctx->src = sg_next(pctx->src);
558 gctx->cryptlen = cryptlen;
559 gctx->complete = gcm_dec_hash_continue;
560
561 return gcm_hash(req, flags);
562}
563
564static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
565{
566 struct aead_instance *inst = aead_alg_instance(tfm);
567 struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
568 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
569 struct crypto_skcipher *ctr;
570 struct crypto_ahash *ghash;
571 unsigned long align;
572 int err;
573
574 ghash = crypto_spawn_ahash(&ictx->ghash);
575 if (IS_ERR(ghash))
576 return PTR_ERR(ghash);
577
578 ctr = crypto_spawn_skcipher(&ictx->ctr);
579 err = PTR_ERR(ctr);
580 if (IS_ERR(ctr))
581 goto err_free_hash;
582
583 ctx->ctr = ctr;
584 ctx->ghash = ghash;
585
586 align = crypto_aead_alignmask(tfm);
587 align &= ~(crypto_tfm_ctx_alignment() - 1);
588 crypto_aead_set_reqsize(tfm,
589 align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
590 max(sizeof(struct skcipher_request) +
591 crypto_skcipher_reqsize(ctr),
592 sizeof(struct ahash_request) +
593 crypto_ahash_reqsize(ghash)));
594
595 return 0;
596
597err_free_hash:
598 crypto_free_ahash(ghash);
599 return err;
600}
601
602static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
603{
604 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
605
606 crypto_free_ahash(ctx->ghash);
607 crypto_free_skcipher(ctx->ctr);
608}
609
610static void crypto_gcm_free(struct aead_instance *inst)
611{
612 struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
613
614 crypto_drop_skcipher(&ctx->ctr);
615 crypto_drop_ahash(&ctx->ghash);
616 kfree(inst);
617}
618
619static int crypto_gcm_create_common(struct crypto_template *tmpl,
620 struct rtattr **tb,
621 const char *full_name,
622 const char *ctr_name,
623 const char *ghash_name)
624{
625 struct crypto_attr_type *algt;
626 struct aead_instance *inst;
627 struct skcipher_alg *ctr;
628 struct crypto_alg *ghash_alg;
629 struct hash_alg_common *ghash;
630 struct gcm_instance_ctx *ctx;
631 int err;
632
633 algt = crypto_get_attr_type(tb);
634 if (IS_ERR(algt))
635 return PTR_ERR(algt);
636
637 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
638 return -EINVAL;
639
640 ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
641 CRYPTO_ALG_TYPE_HASH,
642 CRYPTO_ALG_TYPE_AHASH_MASK |
643 crypto_requires_sync(algt->type,
644 algt->mask));
645 if (IS_ERR(ghash_alg))
646 return PTR_ERR(ghash_alg);
647
648 ghash = __crypto_hash_alg_common(ghash_alg);
649
650 err = -ENOMEM;
651 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
652 if (!inst)
653 goto out_put_ghash;
654
655 ctx = aead_instance_ctx(inst);
656 err = crypto_init_ahash_spawn(&ctx->ghash, ghash,
657 aead_crypto_instance(inst));
658 if (err)
659 goto err_free_inst;
660
661 err = -EINVAL;
662 if (ghash->digestsize != 16)
663 goto err_drop_ghash;
664
665 crypto_set_skcipher_spawn(&ctx->ctr, aead_crypto_instance(inst));
666 err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
667 crypto_requires_sync(algt->type,
668 algt->mask));
669 if (err)
670 goto err_drop_ghash;
671
672 ctr = crypto_spawn_skcipher_alg(&ctx->ctr);
673
674 /* We only support 16-byte blocks. */
675 err = -EINVAL;
676 if (crypto_skcipher_alg_ivsize(ctr) != 16)
677 goto out_put_ctr;
678
679 /* Not a stream cipher? */
680 if (ctr->base.cra_blocksize != 1)
681 goto out_put_ctr;
682
683 err = -ENAMETOOLONG;
684 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
685 "gcm_base(%s,%s)", ctr->base.cra_driver_name,
686 ghash_alg->cra_driver_name) >=
687 CRYPTO_MAX_ALG_NAME)
688 goto out_put_ctr;
689
690 memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
691
692 inst->alg.base.cra_flags = (ghash->base.cra_flags |
693 ctr->base.cra_flags) & CRYPTO_ALG_ASYNC;
694 inst->alg.base.cra_priority = (ghash->base.cra_priority +
695 ctr->base.cra_priority) / 2;
696 inst->alg.base.cra_blocksize = 1;
697 inst->alg.base.cra_alignmask = ghash->base.cra_alignmask |
698 ctr->base.cra_alignmask;
699 inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
700 inst->alg.ivsize = 12;
701 inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
702 inst->alg.maxauthsize = 16;
703 inst->alg.init = crypto_gcm_init_tfm;
704 inst->alg.exit = crypto_gcm_exit_tfm;
705 inst->alg.setkey = crypto_gcm_setkey;
706 inst->alg.setauthsize = crypto_gcm_setauthsize;
707 inst->alg.encrypt = crypto_gcm_encrypt;
708 inst->alg.decrypt = crypto_gcm_decrypt;
709
710 inst->free = crypto_gcm_free;
711
712 err = aead_register_instance(tmpl, inst);
713 if (err)
714 goto out_put_ctr;
715
716out_put_ghash:
717 crypto_mod_put(ghash_alg);
718 return err;
719
720out_put_ctr:
721 crypto_drop_skcipher(&ctx->ctr);
722err_drop_ghash:
723 crypto_drop_ahash(&ctx->ghash);
724err_free_inst:
725 kfree(inst);
726 goto out_put_ghash;
727}
728
729static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
730{
731 const char *cipher_name;
732 char ctr_name[CRYPTO_MAX_ALG_NAME];
733 char full_name[CRYPTO_MAX_ALG_NAME];
734
735 cipher_name = crypto_attr_alg_name(tb[1]);
736 if (IS_ERR(cipher_name))
737 return PTR_ERR(cipher_name);
738
739 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
740 CRYPTO_MAX_ALG_NAME)
741 return -ENAMETOOLONG;
742
743 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >=
744 CRYPTO_MAX_ALG_NAME)
745 return -ENAMETOOLONG;
746
747 return crypto_gcm_create_common(tmpl, tb, full_name,
748 ctr_name, "ghash");
749}
750
751static struct crypto_template crypto_gcm_tmpl = {
752 .name = "gcm",
753 .create = crypto_gcm_create,
754 .module = THIS_MODULE,
755};
756
757static int crypto_gcm_base_create(struct crypto_template *tmpl,
758 struct rtattr **tb)
759{
760 const char *ctr_name;
761 const char *ghash_name;
762 char full_name[CRYPTO_MAX_ALG_NAME];
763
764 ctr_name = crypto_attr_alg_name(tb[1]);
765 if (IS_ERR(ctr_name))
766 return PTR_ERR(ctr_name);
767
768 ghash_name = crypto_attr_alg_name(tb[2]);
769 if (IS_ERR(ghash_name))
770 return PTR_ERR(ghash_name);
771
772 if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)",
773 ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME)
774 return -ENAMETOOLONG;
775
776 return crypto_gcm_create_common(tmpl, tb, full_name,
777 ctr_name, ghash_name);
778}
779
780static struct crypto_template crypto_gcm_base_tmpl = {
781 .name = "gcm_base",
782 .create = crypto_gcm_base_create,
783 .module = THIS_MODULE,
784};
785
786static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
787 unsigned int keylen)
788{
789 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
790 struct crypto_aead *child = ctx->child;
791 int err;
792
793 if (keylen < 4)
794 return -EINVAL;
795
796 keylen -= 4;
797 memcpy(ctx->nonce, key + keylen, 4);
798
799 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
800 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
801 CRYPTO_TFM_REQ_MASK);
802 err = crypto_aead_setkey(child, key, keylen);
803 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
804 CRYPTO_TFM_RES_MASK);
805
806 return err;
807}
808
809static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
810 unsigned int authsize)
811{
812 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
813
814 switch (authsize) {
815 case 8:
816 case 12:
817 case 16:
818 break;
819 default:
820 return -EINVAL;
821 }
822
823 return crypto_aead_setauthsize(ctx->child, authsize);
824}
825
826static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
827{
828 struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req);
829 struct crypto_aead *aead = crypto_aead_reqtfm(req);
830 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
831 struct aead_request *subreq = &rctx->subreq;
832 struct crypto_aead *child = ctx->child;
833 struct scatterlist *sg;
834 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
835 crypto_aead_alignmask(child) + 1);
836
837 scatterwalk_map_and_copy(iv + 12, req->src, 0, req->assoclen - 8, 0);
838
839 memcpy(iv, ctx->nonce, 4);
840 memcpy(iv + 4, req->iv, 8);
841
842 sg_init_table(rctx->src, 3);
843 sg_set_buf(rctx->src, iv + 12, req->assoclen - 8);
844 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
845 if (sg != rctx->src + 1)
846 sg_chain(rctx->src, 2, sg);
847
848 if (req->src != req->dst) {
849 sg_init_table(rctx->dst, 3);
850 sg_set_buf(rctx->dst, iv + 12, req->assoclen - 8);
851 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
852 if (sg != rctx->dst + 1)
853 sg_chain(rctx->dst, 2, sg);
854 }
855
856 aead_request_set_tfm(subreq, child);
857 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
858 req->base.data);
859 aead_request_set_crypt(subreq, rctx->src,
860 req->src == req->dst ? rctx->src : rctx->dst,
861 req->cryptlen, iv);
862 aead_request_set_ad(subreq, req->assoclen - 8);
863
864 return subreq;
865}
866
867static int crypto_rfc4106_encrypt(struct aead_request *req)
868{
869 if (req->assoclen != 16 && req->assoclen != 20)
870 return -EINVAL;
871
872 req = crypto_rfc4106_crypt(req);
873
874 return crypto_aead_encrypt(req);
875}
876
877static int crypto_rfc4106_decrypt(struct aead_request *req)
878{
879 if (req->assoclen != 16 && req->assoclen != 20)
880 return -EINVAL;
881
882 req = crypto_rfc4106_crypt(req);
883
884 return crypto_aead_decrypt(req);
885}
886
887static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
888{
889 struct aead_instance *inst = aead_alg_instance(tfm);
890 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
891 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
892 struct crypto_aead *aead;
893 unsigned long align;
894
895 aead = crypto_spawn_aead(spawn);
896 if (IS_ERR(aead))
897 return PTR_ERR(aead);
898
899 ctx->child = aead;
900
901 align = crypto_aead_alignmask(aead);
902 align &= ~(crypto_tfm_ctx_alignment() - 1);
903 crypto_aead_set_reqsize(
904 tfm,
905 sizeof(struct crypto_rfc4106_req_ctx) +
906 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
907 align + 24);
908
909 return 0;
910}
911
912static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
913{
914 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
915
916 crypto_free_aead(ctx->child);
917}
918
919static void crypto_rfc4106_free(struct aead_instance *inst)
920{
921 crypto_drop_aead(aead_instance_ctx(inst));
922 kfree(inst);
923}
924
925static int crypto_rfc4106_create(struct crypto_template *tmpl,
926 struct rtattr **tb)
927{
928 struct crypto_attr_type *algt;
929 struct aead_instance *inst;
930 struct crypto_aead_spawn *spawn;
931 struct aead_alg *alg;
932 const char *ccm_name;
933 int err;
934
935 algt = crypto_get_attr_type(tb);
936 if (IS_ERR(algt))
937 return PTR_ERR(algt);
938
939 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
940 return -EINVAL;
941
942 ccm_name = crypto_attr_alg_name(tb[1]);
943 if (IS_ERR(ccm_name))
944 return PTR_ERR(ccm_name);
945
946 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
947 if (!inst)
948 return -ENOMEM;
949
950 spawn = aead_instance_ctx(inst);
951 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
952 err = crypto_grab_aead(spawn, ccm_name, 0,
953 crypto_requires_sync(algt->type, algt->mask));
954 if (err)
955 goto out_free_inst;
956
957 alg = crypto_spawn_aead_alg(spawn);
958
959 err = -EINVAL;
960
961 /* Underlying IV size must be 12. */
962 if (crypto_aead_alg_ivsize(alg) != 12)
963 goto out_drop_alg;
964
965 /* Not a stream cipher? */
966 if (alg->base.cra_blocksize != 1)
967 goto out_drop_alg;
968
969 err = -ENAMETOOLONG;
970 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
971 "rfc4106(%s)", alg->base.cra_name) >=
972 CRYPTO_MAX_ALG_NAME ||
973 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
974 "rfc4106(%s)", alg->base.cra_driver_name) >=
975 CRYPTO_MAX_ALG_NAME)
976 goto out_drop_alg;
977
978 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
979 inst->alg.base.cra_priority = alg->base.cra_priority;
980 inst->alg.base.cra_blocksize = 1;
981 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
982
983 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
984
985 inst->alg.ivsize = 8;
986 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
987 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
988
989 inst->alg.init = crypto_rfc4106_init_tfm;
990 inst->alg.exit = crypto_rfc4106_exit_tfm;
991
992 inst->alg.setkey = crypto_rfc4106_setkey;
993 inst->alg.setauthsize = crypto_rfc4106_setauthsize;
994 inst->alg.encrypt = crypto_rfc4106_encrypt;
995 inst->alg.decrypt = crypto_rfc4106_decrypt;
996
997 inst->free = crypto_rfc4106_free;
998
999 err = aead_register_instance(tmpl, inst);
1000 if (err)
1001 goto out_drop_alg;
1002
1003out:
1004 return err;
1005
1006out_drop_alg:
1007 crypto_drop_aead(spawn);
1008out_free_inst:
1009 kfree(inst);
1010 goto out;
1011}
1012
1013static struct crypto_template crypto_rfc4106_tmpl = {
1014 .name = "rfc4106",
1015 .create = crypto_rfc4106_create,
1016 .module = THIS_MODULE,
1017};
1018
1019static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
1020 unsigned int keylen)
1021{
1022 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
1023 struct crypto_aead *child = ctx->child;
1024 int err;
1025
1026 if (keylen < 4)
1027 return -EINVAL;
1028
1029 keylen -= 4;
1030 memcpy(ctx->nonce, key + keylen, 4);
1031
1032 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
1033 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
1034 CRYPTO_TFM_REQ_MASK);
1035 err = crypto_aead_setkey(child, key, keylen);
1036 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
1037 CRYPTO_TFM_RES_MASK);
1038
1039 return err;
1040}
1041
1042static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
1043 unsigned int authsize)
1044{
1045 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
1046
1047 if (authsize != 16)
1048 return -EINVAL;
1049
1050 return crypto_aead_setauthsize(ctx->child, authsize);
1051}
1052
1053static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
1054{
1055 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1056 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1057 struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
1058 struct aead_request *subreq = &rctx->subreq;
1059 unsigned int authsize = crypto_aead_authsize(aead);
1060 u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
1061 crypto_aead_alignmask(ctx->child) + 1);
1062 int err;
1063
1064 if (req->src != req->dst) {
1065 err = crypto_rfc4543_copy_src_to_dst(req, enc);
1066 if (err)
1067 return err;
1068 }
1069
1070 memcpy(iv, ctx->nonce, 4);
1071 memcpy(iv + 4, req->iv, 8);
1072
1073 aead_request_set_tfm(subreq, ctx->child);
1074 aead_request_set_callback(subreq, req->base.flags,
1075 req->base.complete, req->base.data);
1076 aead_request_set_crypt(subreq, req->src, req->dst,
1077 enc ? 0 : authsize, iv);
1078 aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
1079 subreq->cryptlen);
1080
1081 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
1082}
1083
1084static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
1085{
1086 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1087 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1088 unsigned int authsize = crypto_aead_authsize(aead);
1089 unsigned int nbytes = req->assoclen + req->cryptlen -
1090 (enc ? 0 : authsize);
1091 SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null);
1092
1093 skcipher_request_set_tfm(nreq, ctx->null);
1094 skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL);
1095 skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL);
1096
1097 return crypto_skcipher_encrypt(nreq);
1098}
1099
1100static int crypto_rfc4543_encrypt(struct aead_request *req)
1101{
1102 return crypto_rfc4543_crypt(req, true);
1103}
1104
1105static int crypto_rfc4543_decrypt(struct aead_request *req)
1106{
1107 return crypto_rfc4543_crypt(req, false);
1108}
1109
1110static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
1111{
1112 struct aead_instance *inst = aead_alg_instance(tfm);
1113 struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst);
1114 struct crypto_aead_spawn *spawn = &ictx->aead;
1115 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1116 struct crypto_aead *aead;
1117 struct crypto_skcipher *null;
1118 unsigned long align;
1119 int err = 0;
1120
1121 aead = crypto_spawn_aead(spawn);
1122 if (IS_ERR(aead))
1123 return PTR_ERR(aead);
1124
1125 null = crypto_get_default_null_skcipher2();
1126 err = PTR_ERR(null);
1127 if (IS_ERR(null))
1128 goto err_free_aead;
1129
1130 ctx->child = aead;
1131 ctx->null = null;
1132
1133 align = crypto_aead_alignmask(aead);
1134 align &= ~(crypto_tfm_ctx_alignment() - 1);
1135 crypto_aead_set_reqsize(
1136 tfm,
1137 sizeof(struct crypto_rfc4543_req_ctx) +
1138 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
1139 align + 12);
1140
1141 return 0;
1142
1143err_free_aead:
1144 crypto_free_aead(aead);
1145 return err;
1146}
1147
1148static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
1149{
1150 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1151
1152 crypto_free_aead(ctx->child);
1153 crypto_put_default_null_skcipher2();
1154}
1155
1156static void crypto_rfc4543_free(struct aead_instance *inst)
1157{
1158 struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst);
1159
1160 crypto_drop_aead(&ctx->aead);
1161
1162 kfree(inst);
1163}
1164
1165static int crypto_rfc4543_create(struct crypto_template *tmpl,
1166 struct rtattr **tb)
1167{
1168 struct crypto_attr_type *algt;
1169 struct aead_instance *inst;
1170 struct crypto_aead_spawn *spawn;
1171 struct aead_alg *alg;
1172 struct crypto_rfc4543_instance_ctx *ctx;
1173 const char *ccm_name;
1174 int err;
1175
1176 algt = crypto_get_attr_type(tb);
1177 if (IS_ERR(algt))
1178 return PTR_ERR(algt);
1179
1180 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
1181 return -EINVAL;
1182
1183 ccm_name = crypto_attr_alg_name(tb[1]);
1184 if (IS_ERR(ccm_name))
1185 return PTR_ERR(ccm_name);
1186
1187 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1188 if (!inst)
1189 return -ENOMEM;
1190
1191 ctx = aead_instance_ctx(inst);
1192 spawn = &ctx->aead;
1193 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
1194 err = crypto_grab_aead(spawn, ccm_name, 0,
1195 crypto_requires_sync(algt->type, algt->mask));
1196 if (err)
1197 goto out_free_inst;
1198
1199 alg = crypto_spawn_aead_alg(spawn);
1200
1201 err = -EINVAL;
1202
1203 /* Underlying IV size must be 12. */
1204 if (crypto_aead_alg_ivsize(alg) != 12)
1205 goto out_drop_alg;
1206
1207 /* Not a stream cipher? */
1208 if (alg->base.cra_blocksize != 1)
1209 goto out_drop_alg;
1210
1211 err = -ENAMETOOLONG;
1212 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
1213 "rfc4543(%s)", alg->base.cra_name) >=
1214 CRYPTO_MAX_ALG_NAME ||
1215 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1216 "rfc4543(%s)", alg->base.cra_driver_name) >=
1217 CRYPTO_MAX_ALG_NAME)
1218 goto out_drop_alg;
1219
1220 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
1221 inst->alg.base.cra_priority = alg->base.cra_priority;
1222 inst->alg.base.cra_blocksize = 1;
1223 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
1224
1225 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
1226
1227 inst->alg.ivsize = 8;
1228 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
1229 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
1230
1231 inst->alg.init = crypto_rfc4543_init_tfm;
1232 inst->alg.exit = crypto_rfc4543_exit_tfm;
1233
1234 inst->alg.setkey = crypto_rfc4543_setkey;
1235 inst->alg.setauthsize = crypto_rfc4543_setauthsize;
1236 inst->alg.encrypt = crypto_rfc4543_encrypt;
1237 inst->alg.decrypt = crypto_rfc4543_decrypt;
1238
1239 inst->free = crypto_rfc4543_free,
1240
1241 err = aead_register_instance(tmpl, inst);
1242 if (err)
1243 goto out_drop_alg;
1244
1245out:
1246 return err;
1247
1248out_drop_alg:
1249 crypto_drop_aead(spawn);
1250out_free_inst:
1251 kfree(inst);
1252 goto out;
1253}
1254
1255static struct crypto_template crypto_rfc4543_tmpl = {
1256 .name = "rfc4543",
1257 .create = crypto_rfc4543_create,
1258 .module = THIS_MODULE,
1259};
1260
1261static int __init crypto_gcm_module_init(void)
1262{
1263 int err;
1264
1265 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
1266 if (!gcm_zeroes)
1267 return -ENOMEM;
1268
1269 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
1270
1271 err = crypto_register_template(&crypto_gcm_base_tmpl);
1272 if (err)
1273 goto out;
1274
1275 err = crypto_register_template(&crypto_gcm_tmpl);
1276 if (err)
1277 goto out_undo_base;
1278
1279 err = crypto_register_template(&crypto_rfc4106_tmpl);
1280 if (err)
1281 goto out_undo_gcm;
1282
1283 err = crypto_register_template(&crypto_rfc4543_tmpl);
1284 if (err)
1285 goto out_undo_rfc4106;
1286
1287 return 0;
1288
1289out_undo_rfc4106:
1290 crypto_unregister_template(&crypto_rfc4106_tmpl);
1291out_undo_gcm:
1292 crypto_unregister_template(&crypto_gcm_tmpl);
1293out_undo_base:
1294 crypto_unregister_template(&crypto_gcm_base_tmpl);
1295out:
1296 kfree(gcm_zeroes);
1297 return err;
1298}
1299
1300static void __exit crypto_gcm_module_exit(void)
1301{
1302 kfree(gcm_zeroes);
1303 crypto_unregister_template(&crypto_rfc4543_tmpl);
1304 crypto_unregister_template(&crypto_rfc4106_tmpl);
1305 crypto_unregister_template(&crypto_gcm_tmpl);
1306 crypto_unregister_template(&crypto_gcm_base_tmpl);
1307}
1308
1309module_init(crypto_gcm_module_init);
1310module_exit(crypto_gcm_module_exit);
1311
1312MODULE_LICENSE("GPL");
1313MODULE_DESCRIPTION("Galois/Counter Mode");
1314MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1315MODULE_ALIAS_CRYPTO("gcm_base");
1316MODULE_ALIAS_CRYPTO("rfc4106");
1317MODULE_ALIAS_CRYPTO("rfc4543");
1318MODULE_ALIAS_CRYPTO("gcm");