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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * GCM: Galois/Counter Mode.
4 *
5 * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
6 */
7
8#include <crypto/gf128mul.h>
9#include <crypto/internal/aead.h>
10#include <crypto/internal/skcipher.h>
11#include <crypto/internal/hash.h>
12#include <crypto/null.h>
13#include <crypto/scatterwalk.h>
14#include <crypto/gcm.h>
15#include <crypto/hash.h>
16#include "internal.h"
17#include <linux/err.h>
18#include <linux/init.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/slab.h>
22
23struct gcm_instance_ctx {
24 struct crypto_skcipher_spawn ctr;
25 struct crypto_ahash_spawn ghash;
26};
27
28struct crypto_gcm_ctx {
29 struct crypto_skcipher *ctr;
30 struct crypto_ahash *ghash;
31};
32
33struct crypto_rfc4106_ctx {
34 struct crypto_aead *child;
35 u8 nonce[4];
36};
37
38struct crypto_rfc4106_req_ctx {
39 struct scatterlist src[3];
40 struct scatterlist dst[3];
41 struct aead_request subreq;
42};
43
44struct crypto_rfc4543_instance_ctx {
45 struct crypto_aead_spawn aead;
46};
47
48struct crypto_rfc4543_ctx {
49 struct crypto_aead *child;
50 struct crypto_sync_skcipher *null;
51 u8 nonce[4];
52};
53
54struct crypto_rfc4543_req_ctx {
55 struct aead_request subreq;
56};
57
58struct crypto_gcm_ghash_ctx {
59 unsigned int cryptlen;
60 struct scatterlist *src;
61 int (*complete)(struct aead_request *req, u32 flags);
62};
63
64struct crypto_gcm_req_priv_ctx {
65 u8 iv[16];
66 u8 auth_tag[16];
67 u8 iauth_tag[16];
68 struct scatterlist src[3];
69 struct scatterlist dst[3];
70 struct scatterlist sg;
71 struct crypto_gcm_ghash_ctx ghash_ctx;
72 union {
73 struct ahash_request ahreq;
74 struct skcipher_request skreq;
75 } u;
76};
77
78static struct {
79 u8 buf[16];
80 struct scatterlist sg;
81} *gcm_zeroes;
82
83static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
84
85static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
86 struct aead_request *req)
87{
88 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
89
90 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
91}
92
93static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
94 unsigned int keylen)
95{
96 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
97 struct crypto_ahash *ghash = ctx->ghash;
98 struct crypto_skcipher *ctr = ctx->ctr;
99 struct {
100 be128 hash;
101 u8 iv[16];
102
103 struct crypto_wait wait;
104
105 struct scatterlist sg[1];
106 struct skcipher_request req;
107 } *data;
108 int err;
109
110 crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
111 crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
112 CRYPTO_TFM_REQ_MASK);
113 err = crypto_skcipher_setkey(ctr, key, keylen);
114 crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) &
115 CRYPTO_TFM_RES_MASK);
116 if (err)
117 return err;
118
119 data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr),
120 GFP_KERNEL);
121 if (!data)
122 return -ENOMEM;
123
124 crypto_init_wait(&data->wait);
125 sg_init_one(data->sg, &data->hash, sizeof(data->hash));
126 skcipher_request_set_tfm(&data->req, ctr);
127 skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
128 CRYPTO_TFM_REQ_MAY_BACKLOG,
129 crypto_req_done,
130 &data->wait);
131 skcipher_request_set_crypt(&data->req, data->sg, data->sg,
132 sizeof(data->hash), data->iv);
133
134 err = crypto_wait_req(crypto_skcipher_encrypt(&data->req),
135 &data->wait);
136
137 if (err)
138 goto out;
139
140 crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
141 crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
142 CRYPTO_TFM_REQ_MASK);
143 err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
144 crypto_aead_set_flags(aead, crypto_ahash_get_flags(ghash) &
145 CRYPTO_TFM_RES_MASK);
146
147out:
148 kzfree(data);
149 return err;
150}
151
152static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
153 unsigned int authsize)
154{
155 return crypto_gcm_check_authsize(authsize);
156}
157
158static void crypto_gcm_init_common(struct aead_request *req)
159{
160 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
161 __be32 counter = cpu_to_be32(1);
162 struct scatterlist *sg;
163
164 memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
165 memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE);
166 memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4);
167
168 sg_init_table(pctx->src, 3);
169 sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
170 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
171 if (sg != pctx->src + 1)
172 sg_chain(pctx->src, 2, sg);
173
174 if (req->src != req->dst) {
175 sg_init_table(pctx->dst, 3);
176 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
177 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
178 if (sg != pctx->dst + 1)
179 sg_chain(pctx->dst, 2, sg);
180 }
181}
182
183static void crypto_gcm_init_crypt(struct aead_request *req,
184 unsigned int cryptlen)
185{
186 struct crypto_aead *aead = crypto_aead_reqtfm(req);
187 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
188 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
189 struct skcipher_request *skreq = &pctx->u.skreq;
190 struct scatterlist *dst;
191
192 dst = req->src == req->dst ? pctx->src : pctx->dst;
193
194 skcipher_request_set_tfm(skreq, ctx->ctr);
195 skcipher_request_set_crypt(skreq, pctx->src, dst,
196 cryptlen + sizeof(pctx->auth_tag),
197 pctx->iv);
198}
199
200static inline unsigned int gcm_remain(unsigned int len)
201{
202 len &= 0xfU;
203 return len ? 16 - len : 0;
204}
205
206static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
207
208static int gcm_hash_update(struct aead_request *req,
209 crypto_completion_t compl,
210 struct scatterlist *src,
211 unsigned int len, u32 flags)
212{
213 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
214 struct ahash_request *ahreq = &pctx->u.ahreq;
215
216 ahash_request_set_callback(ahreq, flags, compl, req);
217 ahash_request_set_crypt(ahreq, src, NULL, len);
218
219 return crypto_ahash_update(ahreq);
220}
221
222static int gcm_hash_remain(struct aead_request *req,
223 unsigned int remain,
224 crypto_completion_t compl, u32 flags)
225{
226 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
227}
228
229static int gcm_hash_len(struct aead_request *req, u32 flags)
230{
231 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
232 struct ahash_request *ahreq = &pctx->u.ahreq;
233 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
234 be128 lengths;
235
236 lengths.a = cpu_to_be64(req->assoclen * 8);
237 lengths.b = cpu_to_be64(gctx->cryptlen * 8);
238 memcpy(pctx->iauth_tag, &lengths, 16);
239 sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
240 ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
241 ahash_request_set_crypt(ahreq, &pctx->sg,
242 pctx->iauth_tag, sizeof(lengths));
243
244 return crypto_ahash_finup(ahreq);
245}
246
247static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
248{
249 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
250 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
251
252 return gctx->complete(req, flags);
253}
254
255static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
256{
257 struct aead_request *req = areq->data;
258
259 if (err)
260 goto out;
261
262 err = gcm_hash_len_continue(req, 0);
263 if (err == -EINPROGRESS)
264 return;
265
266out:
267 aead_request_complete(req, err);
268}
269
270static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
271{
272 return gcm_hash_len(req, flags) ?:
273 gcm_hash_len_continue(req, flags);
274}
275
276static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
277 int err)
278{
279 struct aead_request *req = areq->data;
280
281 if (err)
282 goto out;
283
284 err = gcm_hash_crypt_remain_continue(req, 0);
285 if (err == -EINPROGRESS)
286 return;
287
288out:
289 aead_request_complete(req, err);
290}
291
292static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
293{
294 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
295 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
296 unsigned int remain;
297
298 remain = gcm_remain(gctx->cryptlen);
299 if (remain)
300 return gcm_hash_remain(req, remain,
301 gcm_hash_crypt_remain_done, flags) ?:
302 gcm_hash_crypt_remain_continue(req, flags);
303
304 return gcm_hash_crypt_remain_continue(req, flags);
305}
306
307static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
308{
309 struct aead_request *req = areq->data;
310
311 if (err)
312 goto out;
313
314 err = gcm_hash_crypt_continue(req, 0);
315 if (err == -EINPROGRESS)
316 return;
317
318out:
319 aead_request_complete(req, err);
320}
321
322static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
323{
324 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
325 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
326
327 if (gctx->cryptlen)
328 return gcm_hash_update(req, gcm_hash_crypt_done,
329 gctx->src, gctx->cryptlen, flags) ?:
330 gcm_hash_crypt_continue(req, flags);
331
332 return gcm_hash_crypt_remain_continue(req, flags);
333}
334
335static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
336 int err)
337{
338 struct aead_request *req = areq->data;
339
340 if (err)
341 goto out;
342
343 err = gcm_hash_assoc_remain_continue(req, 0);
344 if (err == -EINPROGRESS)
345 return;
346
347out:
348 aead_request_complete(req, err);
349}
350
351static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
352{
353 unsigned int remain;
354
355 remain = gcm_remain(req->assoclen);
356 if (remain)
357 return gcm_hash_remain(req, remain,
358 gcm_hash_assoc_remain_done, flags) ?:
359 gcm_hash_assoc_remain_continue(req, flags);
360
361 return gcm_hash_assoc_remain_continue(req, flags);
362}
363
364static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
365{
366 struct aead_request *req = areq->data;
367
368 if (err)
369 goto out;
370
371 err = gcm_hash_assoc_continue(req, 0);
372 if (err == -EINPROGRESS)
373 return;
374
375out:
376 aead_request_complete(req, err);
377}
378
379static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
380{
381 if (req->assoclen)
382 return gcm_hash_update(req, gcm_hash_assoc_done,
383 req->src, req->assoclen, flags) ?:
384 gcm_hash_assoc_continue(req, flags);
385
386 return gcm_hash_assoc_remain_continue(req, flags);
387}
388
389static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
390{
391 struct aead_request *req = areq->data;
392
393 if (err)
394 goto out;
395
396 err = gcm_hash_init_continue(req, 0);
397 if (err == -EINPROGRESS)
398 return;
399
400out:
401 aead_request_complete(req, err);
402}
403
404static int gcm_hash(struct aead_request *req, u32 flags)
405{
406 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
407 struct ahash_request *ahreq = &pctx->u.ahreq;
408 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
409
410 ahash_request_set_tfm(ahreq, ctx->ghash);
411
412 ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
413 return crypto_ahash_init(ahreq) ?:
414 gcm_hash_init_continue(req, flags);
415}
416
417static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
418{
419 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
420 struct crypto_aead *aead = crypto_aead_reqtfm(req);
421 u8 *auth_tag = pctx->auth_tag;
422
423 crypto_xor(auth_tag, pctx->iauth_tag, 16);
424 scatterwalk_map_and_copy(auth_tag, req->dst,
425 req->assoclen + req->cryptlen,
426 crypto_aead_authsize(aead), 1);
427 return 0;
428}
429
430static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
431{
432 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
433 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
434
435 gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
436 gctx->cryptlen = req->cryptlen;
437 gctx->complete = gcm_enc_copy_hash;
438
439 return gcm_hash(req, flags);
440}
441
442static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
443{
444 struct aead_request *req = areq->data;
445
446 if (err)
447 goto out;
448
449 err = gcm_encrypt_continue(req, 0);
450 if (err == -EINPROGRESS)
451 return;
452
453out:
454 aead_request_complete(req, err);
455}
456
457static int crypto_gcm_encrypt(struct aead_request *req)
458{
459 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
460 struct skcipher_request *skreq = &pctx->u.skreq;
461 u32 flags = aead_request_flags(req);
462
463 crypto_gcm_init_common(req);
464 crypto_gcm_init_crypt(req, req->cryptlen);
465 skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req);
466
467 return crypto_skcipher_encrypt(skreq) ?:
468 gcm_encrypt_continue(req, flags);
469}
470
471static int crypto_gcm_verify(struct aead_request *req)
472{
473 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
474 struct crypto_aead *aead = crypto_aead_reqtfm(req);
475 u8 *auth_tag = pctx->auth_tag;
476 u8 *iauth_tag = pctx->iauth_tag;
477 unsigned int authsize = crypto_aead_authsize(aead);
478 unsigned int cryptlen = req->cryptlen - authsize;
479
480 crypto_xor(auth_tag, iauth_tag, 16);
481 scatterwalk_map_and_copy(iauth_tag, req->src,
482 req->assoclen + cryptlen, authsize, 0);
483 return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
484}
485
486static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
487{
488 struct aead_request *req = areq->data;
489
490 if (!err)
491 err = crypto_gcm_verify(req);
492
493 aead_request_complete(req, err);
494}
495
496static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
497{
498 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
499 struct skcipher_request *skreq = &pctx->u.skreq;
500 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
501
502 crypto_gcm_init_crypt(req, gctx->cryptlen);
503 skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req);
504 return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req);
505}
506
507static int crypto_gcm_decrypt(struct aead_request *req)
508{
509 struct crypto_aead *aead = crypto_aead_reqtfm(req);
510 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
511 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
512 unsigned int authsize = crypto_aead_authsize(aead);
513 unsigned int cryptlen = req->cryptlen;
514 u32 flags = aead_request_flags(req);
515
516 cryptlen -= authsize;
517
518 crypto_gcm_init_common(req);
519
520 gctx->src = sg_next(pctx->src);
521 gctx->cryptlen = cryptlen;
522 gctx->complete = gcm_dec_hash_continue;
523
524 return gcm_hash(req, flags);
525}
526
527static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
528{
529 struct aead_instance *inst = aead_alg_instance(tfm);
530 struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
531 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
532 struct crypto_skcipher *ctr;
533 struct crypto_ahash *ghash;
534 unsigned long align;
535 int err;
536
537 ghash = crypto_spawn_ahash(&ictx->ghash);
538 if (IS_ERR(ghash))
539 return PTR_ERR(ghash);
540
541 ctr = crypto_spawn_skcipher(&ictx->ctr);
542 err = PTR_ERR(ctr);
543 if (IS_ERR(ctr))
544 goto err_free_hash;
545
546 ctx->ctr = ctr;
547 ctx->ghash = ghash;
548
549 align = crypto_aead_alignmask(tfm);
550 align &= ~(crypto_tfm_ctx_alignment() - 1);
551 crypto_aead_set_reqsize(tfm,
552 align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
553 max(sizeof(struct skcipher_request) +
554 crypto_skcipher_reqsize(ctr),
555 sizeof(struct ahash_request) +
556 crypto_ahash_reqsize(ghash)));
557
558 return 0;
559
560err_free_hash:
561 crypto_free_ahash(ghash);
562 return err;
563}
564
565static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
566{
567 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
568
569 crypto_free_ahash(ctx->ghash);
570 crypto_free_skcipher(ctx->ctr);
571}
572
573static void crypto_gcm_free(struct aead_instance *inst)
574{
575 struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
576
577 crypto_drop_skcipher(&ctx->ctr);
578 crypto_drop_ahash(&ctx->ghash);
579 kfree(inst);
580}
581
582static int crypto_gcm_create_common(struct crypto_template *tmpl,
583 struct rtattr **tb,
584 const char *ctr_name,
585 const char *ghash_name)
586{
587 struct crypto_attr_type *algt;
588 struct aead_instance *inst;
589 struct skcipher_alg *ctr;
590 struct crypto_alg *ghash_alg;
591 struct hash_alg_common *ghash;
592 struct gcm_instance_ctx *ctx;
593 int err;
594
595 algt = crypto_get_attr_type(tb);
596 if (IS_ERR(algt))
597 return PTR_ERR(algt);
598
599 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
600 return -EINVAL;
601
602 ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
603 CRYPTO_ALG_TYPE_HASH,
604 CRYPTO_ALG_TYPE_AHASH_MASK |
605 crypto_requires_sync(algt->type,
606 algt->mask));
607 if (IS_ERR(ghash_alg))
608 return PTR_ERR(ghash_alg);
609
610 ghash = __crypto_hash_alg_common(ghash_alg);
611
612 err = -ENOMEM;
613 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
614 if (!inst)
615 goto out_put_ghash;
616
617 ctx = aead_instance_ctx(inst);
618 err = crypto_init_ahash_spawn(&ctx->ghash, ghash,
619 aead_crypto_instance(inst));
620 if (err)
621 goto err_free_inst;
622
623 err = -EINVAL;
624 if (strcmp(ghash->base.cra_name, "ghash") != 0 ||
625 ghash->digestsize != 16)
626 goto err_drop_ghash;
627
628 crypto_set_skcipher_spawn(&ctx->ctr, aead_crypto_instance(inst));
629 err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
630 crypto_requires_sync(algt->type,
631 algt->mask));
632 if (err)
633 goto err_drop_ghash;
634
635 ctr = crypto_spawn_skcipher_alg(&ctx->ctr);
636
637 /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */
638 err = -EINVAL;
639 if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
640 crypto_skcipher_alg_ivsize(ctr) != 16 ||
641 ctr->base.cra_blocksize != 1)
642 goto out_put_ctr;
643
644 err = -ENAMETOOLONG;
645 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
646 "gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
647 goto out_put_ctr;
648
649 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
650 "gcm_base(%s,%s)", ctr->base.cra_driver_name,
651 ghash_alg->cra_driver_name) >=
652 CRYPTO_MAX_ALG_NAME)
653 goto out_put_ctr;
654
655 inst->alg.base.cra_flags = (ghash->base.cra_flags |
656 ctr->base.cra_flags) & CRYPTO_ALG_ASYNC;
657 inst->alg.base.cra_priority = (ghash->base.cra_priority +
658 ctr->base.cra_priority) / 2;
659 inst->alg.base.cra_blocksize = 1;
660 inst->alg.base.cra_alignmask = ghash->base.cra_alignmask |
661 ctr->base.cra_alignmask;
662 inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
663 inst->alg.ivsize = GCM_AES_IV_SIZE;
664 inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
665 inst->alg.maxauthsize = 16;
666 inst->alg.init = crypto_gcm_init_tfm;
667 inst->alg.exit = crypto_gcm_exit_tfm;
668 inst->alg.setkey = crypto_gcm_setkey;
669 inst->alg.setauthsize = crypto_gcm_setauthsize;
670 inst->alg.encrypt = crypto_gcm_encrypt;
671 inst->alg.decrypt = crypto_gcm_decrypt;
672
673 inst->free = crypto_gcm_free;
674
675 err = aead_register_instance(tmpl, inst);
676 if (err)
677 goto out_put_ctr;
678
679out_put_ghash:
680 crypto_mod_put(ghash_alg);
681 return err;
682
683out_put_ctr:
684 crypto_drop_skcipher(&ctx->ctr);
685err_drop_ghash:
686 crypto_drop_ahash(&ctx->ghash);
687err_free_inst:
688 kfree(inst);
689 goto out_put_ghash;
690}
691
692static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
693{
694 const char *cipher_name;
695 char ctr_name[CRYPTO_MAX_ALG_NAME];
696
697 cipher_name = crypto_attr_alg_name(tb[1]);
698 if (IS_ERR(cipher_name))
699 return PTR_ERR(cipher_name);
700
701 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
702 CRYPTO_MAX_ALG_NAME)
703 return -ENAMETOOLONG;
704
705 return crypto_gcm_create_common(tmpl, tb, ctr_name, "ghash");
706}
707
708static int crypto_gcm_base_create(struct crypto_template *tmpl,
709 struct rtattr **tb)
710{
711 const char *ctr_name;
712 const char *ghash_name;
713
714 ctr_name = crypto_attr_alg_name(tb[1]);
715 if (IS_ERR(ctr_name))
716 return PTR_ERR(ctr_name);
717
718 ghash_name = crypto_attr_alg_name(tb[2]);
719 if (IS_ERR(ghash_name))
720 return PTR_ERR(ghash_name);
721
722 return crypto_gcm_create_common(tmpl, tb, ctr_name, ghash_name);
723}
724
725static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
726 unsigned int keylen)
727{
728 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
729 struct crypto_aead *child = ctx->child;
730 int err;
731
732 if (keylen < 4)
733 return -EINVAL;
734
735 keylen -= 4;
736 memcpy(ctx->nonce, key + keylen, 4);
737
738 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
739 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
740 CRYPTO_TFM_REQ_MASK);
741 err = crypto_aead_setkey(child, key, keylen);
742 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
743 CRYPTO_TFM_RES_MASK);
744
745 return err;
746}
747
748static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
749 unsigned int authsize)
750{
751 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
752 int err;
753
754 err = crypto_rfc4106_check_authsize(authsize);
755 if (err)
756 return err;
757
758 return crypto_aead_setauthsize(ctx->child, authsize);
759}
760
761static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
762{
763 struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req);
764 struct crypto_aead *aead = crypto_aead_reqtfm(req);
765 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
766 struct aead_request *subreq = &rctx->subreq;
767 struct crypto_aead *child = ctx->child;
768 struct scatterlist *sg;
769 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
770 crypto_aead_alignmask(child) + 1);
771
772 scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0);
773
774 memcpy(iv, ctx->nonce, 4);
775 memcpy(iv + 4, req->iv, 8);
776
777 sg_init_table(rctx->src, 3);
778 sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
779 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
780 if (sg != rctx->src + 1)
781 sg_chain(rctx->src, 2, sg);
782
783 if (req->src != req->dst) {
784 sg_init_table(rctx->dst, 3);
785 sg_set_buf(rctx->dst, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
786 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
787 if (sg != rctx->dst + 1)
788 sg_chain(rctx->dst, 2, sg);
789 }
790
791 aead_request_set_tfm(subreq, child);
792 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
793 req->base.data);
794 aead_request_set_crypt(subreq, rctx->src,
795 req->src == req->dst ? rctx->src : rctx->dst,
796 req->cryptlen, iv);
797 aead_request_set_ad(subreq, req->assoclen - 8);
798
799 return subreq;
800}
801
802static int crypto_rfc4106_encrypt(struct aead_request *req)
803{
804 int err;
805
806 err = crypto_ipsec_check_assoclen(req->assoclen);
807 if (err)
808 return err;
809
810 req = crypto_rfc4106_crypt(req);
811
812 return crypto_aead_encrypt(req);
813}
814
815static int crypto_rfc4106_decrypt(struct aead_request *req)
816{
817 int err;
818
819 err = crypto_ipsec_check_assoclen(req->assoclen);
820 if (err)
821 return err;
822
823 req = crypto_rfc4106_crypt(req);
824
825 return crypto_aead_decrypt(req);
826}
827
828static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
829{
830 struct aead_instance *inst = aead_alg_instance(tfm);
831 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
832 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
833 struct crypto_aead *aead;
834 unsigned long align;
835
836 aead = crypto_spawn_aead(spawn);
837 if (IS_ERR(aead))
838 return PTR_ERR(aead);
839
840 ctx->child = aead;
841
842 align = crypto_aead_alignmask(aead);
843 align &= ~(crypto_tfm_ctx_alignment() - 1);
844 crypto_aead_set_reqsize(
845 tfm,
846 sizeof(struct crypto_rfc4106_req_ctx) +
847 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
848 align + 24);
849
850 return 0;
851}
852
853static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
854{
855 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
856
857 crypto_free_aead(ctx->child);
858}
859
860static void crypto_rfc4106_free(struct aead_instance *inst)
861{
862 crypto_drop_aead(aead_instance_ctx(inst));
863 kfree(inst);
864}
865
866static int crypto_rfc4106_create(struct crypto_template *tmpl,
867 struct rtattr **tb)
868{
869 struct crypto_attr_type *algt;
870 struct aead_instance *inst;
871 struct crypto_aead_spawn *spawn;
872 struct aead_alg *alg;
873 const char *ccm_name;
874 int err;
875
876 algt = crypto_get_attr_type(tb);
877 if (IS_ERR(algt))
878 return PTR_ERR(algt);
879
880 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
881 return -EINVAL;
882
883 ccm_name = crypto_attr_alg_name(tb[1]);
884 if (IS_ERR(ccm_name))
885 return PTR_ERR(ccm_name);
886
887 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
888 if (!inst)
889 return -ENOMEM;
890
891 spawn = aead_instance_ctx(inst);
892 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
893 err = crypto_grab_aead(spawn, ccm_name, 0,
894 crypto_requires_sync(algt->type, algt->mask));
895 if (err)
896 goto out_free_inst;
897
898 alg = crypto_spawn_aead_alg(spawn);
899
900 err = -EINVAL;
901
902 /* Underlying IV size must be 12. */
903 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
904 goto out_drop_alg;
905
906 /* Not a stream cipher? */
907 if (alg->base.cra_blocksize != 1)
908 goto out_drop_alg;
909
910 err = -ENAMETOOLONG;
911 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
912 "rfc4106(%s)", alg->base.cra_name) >=
913 CRYPTO_MAX_ALG_NAME ||
914 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
915 "rfc4106(%s)", alg->base.cra_driver_name) >=
916 CRYPTO_MAX_ALG_NAME)
917 goto out_drop_alg;
918
919 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
920 inst->alg.base.cra_priority = alg->base.cra_priority;
921 inst->alg.base.cra_blocksize = 1;
922 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
923
924 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
925
926 inst->alg.ivsize = GCM_RFC4106_IV_SIZE;
927 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
928 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
929
930 inst->alg.init = crypto_rfc4106_init_tfm;
931 inst->alg.exit = crypto_rfc4106_exit_tfm;
932
933 inst->alg.setkey = crypto_rfc4106_setkey;
934 inst->alg.setauthsize = crypto_rfc4106_setauthsize;
935 inst->alg.encrypt = crypto_rfc4106_encrypt;
936 inst->alg.decrypt = crypto_rfc4106_decrypt;
937
938 inst->free = crypto_rfc4106_free;
939
940 err = aead_register_instance(tmpl, inst);
941 if (err)
942 goto out_drop_alg;
943
944out:
945 return err;
946
947out_drop_alg:
948 crypto_drop_aead(spawn);
949out_free_inst:
950 kfree(inst);
951 goto out;
952}
953
954static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
955 unsigned int keylen)
956{
957 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
958 struct crypto_aead *child = ctx->child;
959 int err;
960
961 if (keylen < 4)
962 return -EINVAL;
963
964 keylen -= 4;
965 memcpy(ctx->nonce, key + keylen, 4);
966
967 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
968 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
969 CRYPTO_TFM_REQ_MASK);
970 err = crypto_aead_setkey(child, key, keylen);
971 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
972 CRYPTO_TFM_RES_MASK);
973
974 return err;
975}
976
977static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
978 unsigned int authsize)
979{
980 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
981
982 if (authsize != 16)
983 return -EINVAL;
984
985 return crypto_aead_setauthsize(ctx->child, authsize);
986}
987
988static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
989{
990 struct crypto_aead *aead = crypto_aead_reqtfm(req);
991 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
992 struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
993 struct aead_request *subreq = &rctx->subreq;
994 unsigned int authsize = crypto_aead_authsize(aead);
995 u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
996 crypto_aead_alignmask(ctx->child) + 1);
997 int err;
998
999 if (req->src != req->dst) {
1000 err = crypto_rfc4543_copy_src_to_dst(req, enc);
1001 if (err)
1002 return err;
1003 }
1004
1005 memcpy(iv, ctx->nonce, 4);
1006 memcpy(iv + 4, req->iv, 8);
1007
1008 aead_request_set_tfm(subreq, ctx->child);
1009 aead_request_set_callback(subreq, req->base.flags,
1010 req->base.complete, req->base.data);
1011 aead_request_set_crypt(subreq, req->src, req->dst,
1012 enc ? 0 : authsize, iv);
1013 aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
1014 subreq->cryptlen);
1015
1016 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
1017}
1018
1019static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
1020{
1021 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1022 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1023 unsigned int authsize = crypto_aead_authsize(aead);
1024 unsigned int nbytes = req->assoclen + req->cryptlen -
1025 (enc ? 0 : authsize);
1026 SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null);
1027
1028 skcipher_request_set_sync_tfm(nreq, ctx->null);
1029 skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL);
1030 skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL);
1031
1032 return crypto_skcipher_encrypt(nreq);
1033}
1034
1035static int crypto_rfc4543_encrypt(struct aead_request *req)
1036{
1037 return crypto_ipsec_check_assoclen(req->assoclen) ?:
1038 crypto_rfc4543_crypt(req, true);
1039}
1040
1041static int crypto_rfc4543_decrypt(struct aead_request *req)
1042{
1043 return crypto_ipsec_check_assoclen(req->assoclen) ?:
1044 crypto_rfc4543_crypt(req, false);
1045}
1046
1047static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
1048{
1049 struct aead_instance *inst = aead_alg_instance(tfm);
1050 struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst);
1051 struct crypto_aead_spawn *spawn = &ictx->aead;
1052 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1053 struct crypto_aead *aead;
1054 struct crypto_sync_skcipher *null;
1055 unsigned long align;
1056 int err = 0;
1057
1058 aead = crypto_spawn_aead(spawn);
1059 if (IS_ERR(aead))
1060 return PTR_ERR(aead);
1061
1062 null = crypto_get_default_null_skcipher();
1063 err = PTR_ERR(null);
1064 if (IS_ERR(null))
1065 goto err_free_aead;
1066
1067 ctx->child = aead;
1068 ctx->null = null;
1069
1070 align = crypto_aead_alignmask(aead);
1071 align &= ~(crypto_tfm_ctx_alignment() - 1);
1072 crypto_aead_set_reqsize(
1073 tfm,
1074 sizeof(struct crypto_rfc4543_req_ctx) +
1075 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
1076 align + GCM_AES_IV_SIZE);
1077
1078 return 0;
1079
1080err_free_aead:
1081 crypto_free_aead(aead);
1082 return err;
1083}
1084
1085static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
1086{
1087 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1088
1089 crypto_free_aead(ctx->child);
1090 crypto_put_default_null_skcipher();
1091}
1092
1093static void crypto_rfc4543_free(struct aead_instance *inst)
1094{
1095 struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst);
1096
1097 crypto_drop_aead(&ctx->aead);
1098
1099 kfree(inst);
1100}
1101
1102static int crypto_rfc4543_create(struct crypto_template *tmpl,
1103 struct rtattr **tb)
1104{
1105 struct crypto_attr_type *algt;
1106 struct aead_instance *inst;
1107 struct crypto_aead_spawn *spawn;
1108 struct aead_alg *alg;
1109 struct crypto_rfc4543_instance_ctx *ctx;
1110 const char *ccm_name;
1111 int err;
1112
1113 algt = crypto_get_attr_type(tb);
1114 if (IS_ERR(algt))
1115 return PTR_ERR(algt);
1116
1117 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
1118 return -EINVAL;
1119
1120 ccm_name = crypto_attr_alg_name(tb[1]);
1121 if (IS_ERR(ccm_name))
1122 return PTR_ERR(ccm_name);
1123
1124 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1125 if (!inst)
1126 return -ENOMEM;
1127
1128 ctx = aead_instance_ctx(inst);
1129 spawn = &ctx->aead;
1130 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
1131 err = crypto_grab_aead(spawn, ccm_name, 0,
1132 crypto_requires_sync(algt->type, algt->mask));
1133 if (err)
1134 goto out_free_inst;
1135
1136 alg = crypto_spawn_aead_alg(spawn);
1137
1138 err = -EINVAL;
1139
1140 /* Underlying IV size must be 12. */
1141 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
1142 goto out_drop_alg;
1143
1144 /* Not a stream cipher? */
1145 if (alg->base.cra_blocksize != 1)
1146 goto out_drop_alg;
1147
1148 err = -ENAMETOOLONG;
1149 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
1150 "rfc4543(%s)", alg->base.cra_name) >=
1151 CRYPTO_MAX_ALG_NAME ||
1152 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1153 "rfc4543(%s)", alg->base.cra_driver_name) >=
1154 CRYPTO_MAX_ALG_NAME)
1155 goto out_drop_alg;
1156
1157 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
1158 inst->alg.base.cra_priority = alg->base.cra_priority;
1159 inst->alg.base.cra_blocksize = 1;
1160 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
1161
1162 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
1163
1164 inst->alg.ivsize = GCM_RFC4543_IV_SIZE;
1165 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
1166 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
1167
1168 inst->alg.init = crypto_rfc4543_init_tfm;
1169 inst->alg.exit = crypto_rfc4543_exit_tfm;
1170
1171 inst->alg.setkey = crypto_rfc4543_setkey;
1172 inst->alg.setauthsize = crypto_rfc4543_setauthsize;
1173 inst->alg.encrypt = crypto_rfc4543_encrypt;
1174 inst->alg.decrypt = crypto_rfc4543_decrypt;
1175
1176 inst->free = crypto_rfc4543_free,
1177
1178 err = aead_register_instance(tmpl, inst);
1179 if (err)
1180 goto out_drop_alg;
1181
1182out:
1183 return err;
1184
1185out_drop_alg:
1186 crypto_drop_aead(spawn);
1187out_free_inst:
1188 kfree(inst);
1189 goto out;
1190}
1191
1192static struct crypto_template crypto_gcm_tmpls[] = {
1193 {
1194 .name = "gcm_base",
1195 .create = crypto_gcm_base_create,
1196 .module = THIS_MODULE,
1197 }, {
1198 .name = "gcm",
1199 .create = crypto_gcm_create,
1200 .module = THIS_MODULE,
1201 }, {
1202 .name = "rfc4106",
1203 .create = crypto_rfc4106_create,
1204 .module = THIS_MODULE,
1205 }, {
1206 .name = "rfc4543",
1207 .create = crypto_rfc4543_create,
1208 .module = THIS_MODULE,
1209 },
1210};
1211
1212static int __init crypto_gcm_module_init(void)
1213{
1214 int err;
1215
1216 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
1217 if (!gcm_zeroes)
1218 return -ENOMEM;
1219
1220 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
1221
1222 err = crypto_register_templates(crypto_gcm_tmpls,
1223 ARRAY_SIZE(crypto_gcm_tmpls));
1224 if (err)
1225 kfree(gcm_zeroes);
1226
1227 return err;
1228}
1229
1230static void __exit crypto_gcm_module_exit(void)
1231{
1232 kfree(gcm_zeroes);
1233 crypto_unregister_templates(crypto_gcm_tmpls,
1234 ARRAY_SIZE(crypto_gcm_tmpls));
1235}
1236
1237subsys_initcall(crypto_gcm_module_init);
1238module_exit(crypto_gcm_module_exit);
1239
1240MODULE_LICENSE("GPL");
1241MODULE_DESCRIPTION("Galois/Counter Mode");
1242MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1243MODULE_ALIAS_CRYPTO("gcm_base");
1244MODULE_ALIAS_CRYPTO("rfc4106");
1245MODULE_ALIAS_CRYPTO("rfc4543");
1246MODULE_ALIAS_CRYPTO("gcm");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * GCM: Galois/Counter Mode.
4 *
5 * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
6 */
7
8#include <crypto/gf128mul.h>
9#include <crypto/internal/aead.h>
10#include <crypto/internal/skcipher.h>
11#include <crypto/internal/hash.h>
12#include <crypto/null.h>
13#include <crypto/scatterwalk.h>
14#include <crypto/gcm.h>
15#include <crypto/hash.h>
16#include <linux/err.h>
17#include <linux/init.h>
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/slab.h>
21
22struct gcm_instance_ctx {
23 struct crypto_skcipher_spawn ctr;
24 struct crypto_ahash_spawn ghash;
25};
26
27struct crypto_gcm_ctx {
28 struct crypto_skcipher *ctr;
29 struct crypto_ahash *ghash;
30};
31
32struct crypto_rfc4106_ctx {
33 struct crypto_aead *child;
34 u8 nonce[4];
35};
36
37struct crypto_rfc4106_req_ctx {
38 struct scatterlist src[3];
39 struct scatterlist dst[3];
40 struct aead_request subreq;
41};
42
43struct crypto_rfc4543_instance_ctx {
44 struct crypto_aead_spawn aead;
45};
46
47struct crypto_rfc4543_ctx {
48 struct crypto_aead *child;
49 struct crypto_sync_skcipher *null;
50 u8 nonce[4];
51};
52
53struct crypto_rfc4543_req_ctx {
54 struct aead_request subreq;
55};
56
57struct crypto_gcm_ghash_ctx {
58 unsigned int cryptlen;
59 struct scatterlist *src;
60 int (*complete)(struct aead_request *req, u32 flags);
61};
62
63struct crypto_gcm_req_priv_ctx {
64 u8 iv[16];
65 u8 auth_tag[16];
66 u8 iauth_tag[16];
67 struct scatterlist src[3];
68 struct scatterlist dst[3];
69 struct scatterlist sg;
70 struct crypto_gcm_ghash_ctx ghash_ctx;
71 union {
72 struct ahash_request ahreq;
73 struct skcipher_request skreq;
74 } u;
75};
76
77static struct {
78 u8 buf[16];
79 struct scatterlist sg;
80} *gcm_zeroes;
81
82static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
83
84static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
85 struct aead_request *req)
86{
87 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
88
89 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
90}
91
92static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
93 unsigned int keylen)
94{
95 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
96 struct crypto_ahash *ghash = ctx->ghash;
97 struct crypto_skcipher *ctr = ctx->ctr;
98 struct {
99 be128 hash;
100 u8 iv[16];
101
102 struct crypto_wait wait;
103
104 struct scatterlist sg[1];
105 struct skcipher_request req;
106 } *data;
107 int err;
108
109 crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
110 crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
111 CRYPTO_TFM_REQ_MASK);
112 err = crypto_skcipher_setkey(ctr, key, keylen);
113 if (err)
114 return err;
115
116 data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr),
117 GFP_KERNEL);
118 if (!data)
119 return -ENOMEM;
120
121 crypto_init_wait(&data->wait);
122 sg_init_one(data->sg, &data->hash, sizeof(data->hash));
123 skcipher_request_set_tfm(&data->req, ctr);
124 skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
125 CRYPTO_TFM_REQ_MAY_BACKLOG,
126 crypto_req_done,
127 &data->wait);
128 skcipher_request_set_crypt(&data->req, data->sg, data->sg,
129 sizeof(data->hash), data->iv);
130
131 err = crypto_wait_req(crypto_skcipher_encrypt(&data->req),
132 &data->wait);
133
134 if (err)
135 goto out;
136
137 crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
138 crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
139 CRYPTO_TFM_REQ_MASK);
140 err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
141out:
142 kfree_sensitive(data);
143 return err;
144}
145
146static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
147 unsigned int authsize)
148{
149 return crypto_gcm_check_authsize(authsize);
150}
151
152static void crypto_gcm_init_common(struct aead_request *req)
153{
154 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
155 __be32 counter = cpu_to_be32(1);
156 struct scatterlist *sg;
157
158 memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
159 memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE);
160 memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4);
161
162 sg_init_table(pctx->src, 3);
163 sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
164 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
165 if (sg != pctx->src + 1)
166 sg_chain(pctx->src, 2, sg);
167
168 if (req->src != req->dst) {
169 sg_init_table(pctx->dst, 3);
170 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
171 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
172 if (sg != pctx->dst + 1)
173 sg_chain(pctx->dst, 2, sg);
174 }
175}
176
177static void crypto_gcm_init_crypt(struct aead_request *req,
178 unsigned int cryptlen)
179{
180 struct crypto_aead *aead = crypto_aead_reqtfm(req);
181 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
182 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
183 struct skcipher_request *skreq = &pctx->u.skreq;
184 struct scatterlist *dst;
185
186 dst = req->src == req->dst ? pctx->src : pctx->dst;
187
188 skcipher_request_set_tfm(skreq, ctx->ctr);
189 skcipher_request_set_crypt(skreq, pctx->src, dst,
190 cryptlen + sizeof(pctx->auth_tag),
191 pctx->iv);
192}
193
194static inline unsigned int gcm_remain(unsigned int len)
195{
196 len &= 0xfU;
197 return len ? 16 - len : 0;
198}
199
200static void gcm_hash_len_done(void *data, int err);
201
202static int gcm_hash_update(struct aead_request *req,
203 crypto_completion_t compl,
204 struct scatterlist *src,
205 unsigned int len, u32 flags)
206{
207 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
208 struct ahash_request *ahreq = &pctx->u.ahreq;
209
210 ahash_request_set_callback(ahreq, flags, compl, req);
211 ahash_request_set_crypt(ahreq, src, NULL, len);
212
213 return crypto_ahash_update(ahreq);
214}
215
216static int gcm_hash_remain(struct aead_request *req,
217 unsigned int remain,
218 crypto_completion_t compl, u32 flags)
219{
220 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
221}
222
223static int gcm_hash_len(struct aead_request *req, u32 flags)
224{
225 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
226 struct ahash_request *ahreq = &pctx->u.ahreq;
227 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
228 be128 lengths;
229
230 lengths.a = cpu_to_be64(req->assoclen * 8);
231 lengths.b = cpu_to_be64(gctx->cryptlen * 8);
232 memcpy(pctx->iauth_tag, &lengths, 16);
233 sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
234 ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
235 ahash_request_set_crypt(ahreq, &pctx->sg,
236 pctx->iauth_tag, sizeof(lengths));
237
238 return crypto_ahash_finup(ahreq);
239}
240
241static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
242{
243 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
244 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
245
246 return gctx->complete(req, flags);
247}
248
249static void gcm_hash_len_done(void *data, int err)
250{
251 struct aead_request *req = data;
252
253 if (err)
254 goto out;
255
256 err = gcm_hash_len_continue(req, 0);
257 if (err == -EINPROGRESS)
258 return;
259
260out:
261 aead_request_complete(req, err);
262}
263
264static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
265{
266 return gcm_hash_len(req, flags) ?:
267 gcm_hash_len_continue(req, flags);
268}
269
270static void gcm_hash_crypt_remain_done(void *data, int err)
271{
272 struct aead_request *req = data;
273
274 if (err)
275 goto out;
276
277 err = gcm_hash_crypt_remain_continue(req, 0);
278 if (err == -EINPROGRESS)
279 return;
280
281out:
282 aead_request_complete(req, err);
283}
284
285static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
286{
287 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
288 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
289 unsigned int remain;
290
291 remain = gcm_remain(gctx->cryptlen);
292 if (remain)
293 return gcm_hash_remain(req, remain,
294 gcm_hash_crypt_remain_done, flags) ?:
295 gcm_hash_crypt_remain_continue(req, flags);
296
297 return gcm_hash_crypt_remain_continue(req, flags);
298}
299
300static void gcm_hash_crypt_done(void *data, int err)
301{
302 struct aead_request *req = data;
303
304 if (err)
305 goto out;
306
307 err = gcm_hash_crypt_continue(req, 0);
308 if (err == -EINPROGRESS)
309 return;
310
311out:
312 aead_request_complete(req, err);
313}
314
315static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
316{
317 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
318 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
319
320 if (gctx->cryptlen)
321 return gcm_hash_update(req, gcm_hash_crypt_done,
322 gctx->src, gctx->cryptlen, flags) ?:
323 gcm_hash_crypt_continue(req, flags);
324
325 return gcm_hash_crypt_remain_continue(req, flags);
326}
327
328static void gcm_hash_assoc_remain_done(void *data, int err)
329{
330 struct aead_request *req = data;
331
332 if (err)
333 goto out;
334
335 err = gcm_hash_assoc_remain_continue(req, 0);
336 if (err == -EINPROGRESS)
337 return;
338
339out:
340 aead_request_complete(req, err);
341}
342
343static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
344{
345 unsigned int remain;
346
347 remain = gcm_remain(req->assoclen);
348 if (remain)
349 return gcm_hash_remain(req, remain,
350 gcm_hash_assoc_remain_done, flags) ?:
351 gcm_hash_assoc_remain_continue(req, flags);
352
353 return gcm_hash_assoc_remain_continue(req, flags);
354}
355
356static void gcm_hash_assoc_done(void *data, int err)
357{
358 struct aead_request *req = data;
359
360 if (err)
361 goto out;
362
363 err = gcm_hash_assoc_continue(req, 0);
364 if (err == -EINPROGRESS)
365 return;
366
367out:
368 aead_request_complete(req, err);
369}
370
371static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
372{
373 if (req->assoclen)
374 return gcm_hash_update(req, gcm_hash_assoc_done,
375 req->src, req->assoclen, flags) ?:
376 gcm_hash_assoc_continue(req, flags);
377
378 return gcm_hash_assoc_remain_continue(req, flags);
379}
380
381static void gcm_hash_init_done(void *data, int err)
382{
383 struct aead_request *req = data;
384
385 if (err)
386 goto out;
387
388 err = gcm_hash_init_continue(req, 0);
389 if (err == -EINPROGRESS)
390 return;
391
392out:
393 aead_request_complete(req, err);
394}
395
396static int gcm_hash(struct aead_request *req, u32 flags)
397{
398 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
399 struct ahash_request *ahreq = &pctx->u.ahreq;
400 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
401
402 ahash_request_set_tfm(ahreq, ctx->ghash);
403
404 ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
405 return crypto_ahash_init(ahreq) ?:
406 gcm_hash_init_continue(req, flags);
407}
408
409static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
410{
411 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
412 struct crypto_aead *aead = crypto_aead_reqtfm(req);
413 u8 *auth_tag = pctx->auth_tag;
414
415 crypto_xor(auth_tag, pctx->iauth_tag, 16);
416 scatterwalk_map_and_copy(auth_tag, req->dst,
417 req->assoclen + req->cryptlen,
418 crypto_aead_authsize(aead), 1);
419 return 0;
420}
421
422static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
423{
424 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
425 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
426
427 gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
428 gctx->cryptlen = req->cryptlen;
429 gctx->complete = gcm_enc_copy_hash;
430
431 return gcm_hash(req, flags);
432}
433
434static void gcm_encrypt_done(void *data, int err)
435{
436 struct aead_request *req = data;
437
438 if (err)
439 goto out;
440
441 err = gcm_encrypt_continue(req, 0);
442 if (err == -EINPROGRESS)
443 return;
444
445out:
446 aead_request_complete(req, err);
447}
448
449static int crypto_gcm_encrypt(struct aead_request *req)
450{
451 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
452 struct skcipher_request *skreq = &pctx->u.skreq;
453 u32 flags = aead_request_flags(req);
454
455 crypto_gcm_init_common(req);
456 crypto_gcm_init_crypt(req, req->cryptlen);
457 skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req);
458
459 return crypto_skcipher_encrypt(skreq) ?:
460 gcm_encrypt_continue(req, flags);
461}
462
463static int crypto_gcm_verify(struct aead_request *req)
464{
465 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
466 struct crypto_aead *aead = crypto_aead_reqtfm(req);
467 u8 *auth_tag = pctx->auth_tag;
468 u8 *iauth_tag = pctx->iauth_tag;
469 unsigned int authsize = crypto_aead_authsize(aead);
470 unsigned int cryptlen = req->cryptlen - authsize;
471
472 crypto_xor(auth_tag, iauth_tag, 16);
473 scatterwalk_map_and_copy(iauth_tag, req->src,
474 req->assoclen + cryptlen, authsize, 0);
475 return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
476}
477
478static void gcm_decrypt_done(void *data, int err)
479{
480 struct aead_request *req = data;
481
482 if (!err)
483 err = crypto_gcm_verify(req);
484
485 aead_request_complete(req, err);
486}
487
488static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
489{
490 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
491 struct skcipher_request *skreq = &pctx->u.skreq;
492 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
493
494 crypto_gcm_init_crypt(req, gctx->cryptlen);
495 skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req);
496 return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req);
497}
498
499static int crypto_gcm_decrypt(struct aead_request *req)
500{
501 struct crypto_aead *aead = crypto_aead_reqtfm(req);
502 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
503 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
504 unsigned int authsize = crypto_aead_authsize(aead);
505 unsigned int cryptlen = req->cryptlen;
506 u32 flags = aead_request_flags(req);
507
508 cryptlen -= authsize;
509
510 crypto_gcm_init_common(req);
511
512 gctx->src = sg_next(pctx->src);
513 gctx->cryptlen = cryptlen;
514 gctx->complete = gcm_dec_hash_continue;
515
516 return gcm_hash(req, flags);
517}
518
519static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
520{
521 struct aead_instance *inst = aead_alg_instance(tfm);
522 struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
523 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
524 struct crypto_skcipher *ctr;
525 struct crypto_ahash *ghash;
526 unsigned long align;
527 int err;
528
529 ghash = crypto_spawn_ahash(&ictx->ghash);
530 if (IS_ERR(ghash))
531 return PTR_ERR(ghash);
532
533 ctr = crypto_spawn_skcipher(&ictx->ctr);
534 err = PTR_ERR(ctr);
535 if (IS_ERR(ctr))
536 goto err_free_hash;
537
538 ctx->ctr = ctr;
539 ctx->ghash = ghash;
540
541 align = crypto_aead_alignmask(tfm);
542 align &= ~(crypto_tfm_ctx_alignment() - 1);
543 crypto_aead_set_reqsize(tfm,
544 align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
545 max(sizeof(struct skcipher_request) +
546 crypto_skcipher_reqsize(ctr),
547 sizeof(struct ahash_request) +
548 crypto_ahash_reqsize(ghash)));
549
550 return 0;
551
552err_free_hash:
553 crypto_free_ahash(ghash);
554 return err;
555}
556
557static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
558{
559 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
560
561 crypto_free_ahash(ctx->ghash);
562 crypto_free_skcipher(ctx->ctr);
563}
564
565static void crypto_gcm_free(struct aead_instance *inst)
566{
567 struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
568
569 crypto_drop_skcipher(&ctx->ctr);
570 crypto_drop_ahash(&ctx->ghash);
571 kfree(inst);
572}
573
574static int crypto_gcm_create_common(struct crypto_template *tmpl,
575 struct rtattr **tb,
576 const char *ctr_name,
577 const char *ghash_name)
578{
579 struct skcipher_alg_common *ctr;
580 u32 mask;
581 struct aead_instance *inst;
582 struct gcm_instance_ctx *ctx;
583 struct hash_alg_common *ghash;
584 int err;
585
586 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
587 if (err)
588 return err;
589
590 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
591 if (!inst)
592 return -ENOMEM;
593 ctx = aead_instance_ctx(inst);
594
595 err = crypto_grab_ahash(&ctx->ghash, aead_crypto_instance(inst),
596 ghash_name, 0, mask);
597 if (err)
598 goto err_free_inst;
599 ghash = crypto_spawn_ahash_alg(&ctx->ghash);
600
601 err = -EINVAL;
602 if (strcmp(ghash->base.cra_name, "ghash") != 0 ||
603 ghash->digestsize != 16)
604 goto err_free_inst;
605
606 err = crypto_grab_skcipher(&ctx->ctr, aead_crypto_instance(inst),
607 ctr_name, 0, mask);
608 if (err)
609 goto err_free_inst;
610 ctr = crypto_spawn_skcipher_alg_common(&ctx->ctr);
611
612 /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */
613 err = -EINVAL;
614 if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
615 ctr->ivsize != 16 || ctr->base.cra_blocksize != 1)
616 goto err_free_inst;
617
618 err = -ENAMETOOLONG;
619 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
620 "gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
621 goto err_free_inst;
622
623 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
624 "gcm_base(%s,%s)", ctr->base.cra_driver_name,
625 ghash->base.cra_driver_name) >=
626 CRYPTO_MAX_ALG_NAME)
627 goto err_free_inst;
628
629 inst->alg.base.cra_priority = (ghash->base.cra_priority +
630 ctr->base.cra_priority) / 2;
631 inst->alg.base.cra_blocksize = 1;
632 inst->alg.base.cra_alignmask = ctr->base.cra_alignmask;
633 inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
634 inst->alg.ivsize = GCM_AES_IV_SIZE;
635 inst->alg.chunksize = ctr->chunksize;
636 inst->alg.maxauthsize = 16;
637 inst->alg.init = crypto_gcm_init_tfm;
638 inst->alg.exit = crypto_gcm_exit_tfm;
639 inst->alg.setkey = crypto_gcm_setkey;
640 inst->alg.setauthsize = crypto_gcm_setauthsize;
641 inst->alg.encrypt = crypto_gcm_encrypt;
642 inst->alg.decrypt = crypto_gcm_decrypt;
643
644 inst->free = crypto_gcm_free;
645
646 err = aead_register_instance(tmpl, inst);
647 if (err) {
648err_free_inst:
649 crypto_gcm_free(inst);
650 }
651 return err;
652}
653
654static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
655{
656 const char *cipher_name;
657 char ctr_name[CRYPTO_MAX_ALG_NAME];
658
659 cipher_name = crypto_attr_alg_name(tb[1]);
660 if (IS_ERR(cipher_name))
661 return PTR_ERR(cipher_name);
662
663 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
664 CRYPTO_MAX_ALG_NAME)
665 return -ENAMETOOLONG;
666
667 return crypto_gcm_create_common(tmpl, tb, ctr_name, "ghash");
668}
669
670static int crypto_gcm_base_create(struct crypto_template *tmpl,
671 struct rtattr **tb)
672{
673 const char *ctr_name;
674 const char *ghash_name;
675
676 ctr_name = crypto_attr_alg_name(tb[1]);
677 if (IS_ERR(ctr_name))
678 return PTR_ERR(ctr_name);
679
680 ghash_name = crypto_attr_alg_name(tb[2]);
681 if (IS_ERR(ghash_name))
682 return PTR_ERR(ghash_name);
683
684 return crypto_gcm_create_common(tmpl, tb, ctr_name, ghash_name);
685}
686
687static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
688 unsigned int keylen)
689{
690 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
691 struct crypto_aead *child = ctx->child;
692
693 if (keylen < 4)
694 return -EINVAL;
695
696 keylen -= 4;
697 memcpy(ctx->nonce, key + keylen, 4);
698
699 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
700 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
701 CRYPTO_TFM_REQ_MASK);
702 return crypto_aead_setkey(child, key, keylen);
703}
704
705static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
706 unsigned int authsize)
707{
708 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
709 int err;
710
711 err = crypto_rfc4106_check_authsize(authsize);
712 if (err)
713 return err;
714
715 return crypto_aead_setauthsize(ctx->child, authsize);
716}
717
718static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
719{
720 struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req);
721 struct crypto_aead *aead = crypto_aead_reqtfm(req);
722 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
723 struct aead_request *subreq = &rctx->subreq;
724 struct crypto_aead *child = ctx->child;
725 struct scatterlist *sg;
726 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
727 crypto_aead_alignmask(child) + 1);
728
729 scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0);
730
731 memcpy(iv, ctx->nonce, 4);
732 memcpy(iv + 4, req->iv, 8);
733
734 sg_init_table(rctx->src, 3);
735 sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
736 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
737 if (sg != rctx->src + 1)
738 sg_chain(rctx->src, 2, sg);
739
740 if (req->src != req->dst) {
741 sg_init_table(rctx->dst, 3);
742 sg_set_buf(rctx->dst, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
743 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
744 if (sg != rctx->dst + 1)
745 sg_chain(rctx->dst, 2, sg);
746 }
747
748 aead_request_set_tfm(subreq, child);
749 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
750 req->base.data);
751 aead_request_set_crypt(subreq, rctx->src,
752 req->src == req->dst ? rctx->src : rctx->dst,
753 req->cryptlen, iv);
754 aead_request_set_ad(subreq, req->assoclen - 8);
755
756 return subreq;
757}
758
759static int crypto_rfc4106_encrypt(struct aead_request *req)
760{
761 int err;
762
763 err = crypto_ipsec_check_assoclen(req->assoclen);
764 if (err)
765 return err;
766
767 req = crypto_rfc4106_crypt(req);
768
769 return crypto_aead_encrypt(req);
770}
771
772static int crypto_rfc4106_decrypt(struct aead_request *req)
773{
774 int err;
775
776 err = crypto_ipsec_check_assoclen(req->assoclen);
777 if (err)
778 return err;
779
780 req = crypto_rfc4106_crypt(req);
781
782 return crypto_aead_decrypt(req);
783}
784
785static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
786{
787 struct aead_instance *inst = aead_alg_instance(tfm);
788 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
789 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
790 struct crypto_aead *aead;
791 unsigned long align;
792
793 aead = crypto_spawn_aead(spawn);
794 if (IS_ERR(aead))
795 return PTR_ERR(aead);
796
797 ctx->child = aead;
798
799 align = crypto_aead_alignmask(aead);
800 align &= ~(crypto_tfm_ctx_alignment() - 1);
801 crypto_aead_set_reqsize(
802 tfm,
803 sizeof(struct crypto_rfc4106_req_ctx) +
804 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
805 align + 24);
806
807 return 0;
808}
809
810static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
811{
812 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
813
814 crypto_free_aead(ctx->child);
815}
816
817static void crypto_rfc4106_free(struct aead_instance *inst)
818{
819 crypto_drop_aead(aead_instance_ctx(inst));
820 kfree(inst);
821}
822
823static int crypto_rfc4106_create(struct crypto_template *tmpl,
824 struct rtattr **tb)
825{
826 u32 mask;
827 struct aead_instance *inst;
828 struct crypto_aead_spawn *spawn;
829 struct aead_alg *alg;
830 int err;
831
832 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
833 if (err)
834 return err;
835
836 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
837 if (!inst)
838 return -ENOMEM;
839
840 spawn = aead_instance_ctx(inst);
841 err = crypto_grab_aead(spawn, aead_crypto_instance(inst),
842 crypto_attr_alg_name(tb[1]), 0, mask);
843 if (err)
844 goto err_free_inst;
845
846 alg = crypto_spawn_aead_alg(spawn);
847
848 err = -EINVAL;
849
850 /* Underlying IV size must be 12. */
851 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
852 goto err_free_inst;
853
854 /* Not a stream cipher? */
855 if (alg->base.cra_blocksize != 1)
856 goto err_free_inst;
857
858 err = -ENAMETOOLONG;
859 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
860 "rfc4106(%s)", alg->base.cra_name) >=
861 CRYPTO_MAX_ALG_NAME ||
862 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
863 "rfc4106(%s)", alg->base.cra_driver_name) >=
864 CRYPTO_MAX_ALG_NAME)
865 goto err_free_inst;
866
867 inst->alg.base.cra_priority = alg->base.cra_priority;
868 inst->alg.base.cra_blocksize = 1;
869 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
870
871 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
872
873 inst->alg.ivsize = GCM_RFC4106_IV_SIZE;
874 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
875 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
876
877 inst->alg.init = crypto_rfc4106_init_tfm;
878 inst->alg.exit = crypto_rfc4106_exit_tfm;
879
880 inst->alg.setkey = crypto_rfc4106_setkey;
881 inst->alg.setauthsize = crypto_rfc4106_setauthsize;
882 inst->alg.encrypt = crypto_rfc4106_encrypt;
883 inst->alg.decrypt = crypto_rfc4106_decrypt;
884
885 inst->free = crypto_rfc4106_free;
886
887 err = aead_register_instance(tmpl, inst);
888 if (err) {
889err_free_inst:
890 crypto_rfc4106_free(inst);
891 }
892 return err;
893}
894
895static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
896 unsigned int keylen)
897{
898 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
899 struct crypto_aead *child = ctx->child;
900
901 if (keylen < 4)
902 return -EINVAL;
903
904 keylen -= 4;
905 memcpy(ctx->nonce, key + keylen, 4);
906
907 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
908 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
909 CRYPTO_TFM_REQ_MASK);
910 return crypto_aead_setkey(child, key, keylen);
911}
912
913static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
914 unsigned int authsize)
915{
916 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
917
918 if (authsize != 16)
919 return -EINVAL;
920
921 return crypto_aead_setauthsize(ctx->child, authsize);
922}
923
924static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
925{
926 struct crypto_aead *aead = crypto_aead_reqtfm(req);
927 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
928 struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
929 struct aead_request *subreq = &rctx->subreq;
930 unsigned int authsize = crypto_aead_authsize(aead);
931 u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
932 crypto_aead_alignmask(ctx->child) + 1);
933 int err;
934
935 if (req->src != req->dst) {
936 err = crypto_rfc4543_copy_src_to_dst(req, enc);
937 if (err)
938 return err;
939 }
940
941 memcpy(iv, ctx->nonce, 4);
942 memcpy(iv + 4, req->iv, 8);
943
944 aead_request_set_tfm(subreq, ctx->child);
945 aead_request_set_callback(subreq, req->base.flags,
946 req->base.complete, req->base.data);
947 aead_request_set_crypt(subreq, req->src, req->dst,
948 enc ? 0 : authsize, iv);
949 aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
950 subreq->cryptlen);
951
952 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
953}
954
955static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
956{
957 struct crypto_aead *aead = crypto_aead_reqtfm(req);
958 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
959 unsigned int authsize = crypto_aead_authsize(aead);
960 unsigned int nbytes = req->assoclen + req->cryptlen -
961 (enc ? 0 : authsize);
962 SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null);
963
964 skcipher_request_set_sync_tfm(nreq, ctx->null);
965 skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL);
966 skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL);
967
968 return crypto_skcipher_encrypt(nreq);
969}
970
971static int crypto_rfc4543_encrypt(struct aead_request *req)
972{
973 return crypto_ipsec_check_assoclen(req->assoclen) ?:
974 crypto_rfc4543_crypt(req, true);
975}
976
977static int crypto_rfc4543_decrypt(struct aead_request *req)
978{
979 return crypto_ipsec_check_assoclen(req->assoclen) ?:
980 crypto_rfc4543_crypt(req, false);
981}
982
983static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
984{
985 struct aead_instance *inst = aead_alg_instance(tfm);
986 struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst);
987 struct crypto_aead_spawn *spawn = &ictx->aead;
988 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
989 struct crypto_aead *aead;
990 struct crypto_sync_skcipher *null;
991 unsigned long align;
992 int err = 0;
993
994 aead = crypto_spawn_aead(spawn);
995 if (IS_ERR(aead))
996 return PTR_ERR(aead);
997
998 null = crypto_get_default_null_skcipher();
999 err = PTR_ERR(null);
1000 if (IS_ERR(null))
1001 goto err_free_aead;
1002
1003 ctx->child = aead;
1004 ctx->null = null;
1005
1006 align = crypto_aead_alignmask(aead);
1007 align &= ~(crypto_tfm_ctx_alignment() - 1);
1008 crypto_aead_set_reqsize(
1009 tfm,
1010 sizeof(struct crypto_rfc4543_req_ctx) +
1011 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
1012 align + GCM_AES_IV_SIZE);
1013
1014 return 0;
1015
1016err_free_aead:
1017 crypto_free_aead(aead);
1018 return err;
1019}
1020
1021static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
1022{
1023 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1024
1025 crypto_free_aead(ctx->child);
1026 crypto_put_default_null_skcipher();
1027}
1028
1029static void crypto_rfc4543_free(struct aead_instance *inst)
1030{
1031 struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst);
1032
1033 crypto_drop_aead(&ctx->aead);
1034
1035 kfree(inst);
1036}
1037
1038static int crypto_rfc4543_create(struct crypto_template *tmpl,
1039 struct rtattr **tb)
1040{
1041 u32 mask;
1042 struct aead_instance *inst;
1043 struct aead_alg *alg;
1044 struct crypto_rfc4543_instance_ctx *ctx;
1045 int err;
1046
1047 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
1048 if (err)
1049 return err;
1050
1051 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1052 if (!inst)
1053 return -ENOMEM;
1054
1055 ctx = aead_instance_ctx(inst);
1056 err = crypto_grab_aead(&ctx->aead, aead_crypto_instance(inst),
1057 crypto_attr_alg_name(tb[1]), 0, mask);
1058 if (err)
1059 goto err_free_inst;
1060
1061 alg = crypto_spawn_aead_alg(&ctx->aead);
1062
1063 err = -EINVAL;
1064
1065 /* Underlying IV size must be 12. */
1066 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
1067 goto err_free_inst;
1068
1069 /* Not a stream cipher? */
1070 if (alg->base.cra_blocksize != 1)
1071 goto err_free_inst;
1072
1073 err = -ENAMETOOLONG;
1074 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
1075 "rfc4543(%s)", alg->base.cra_name) >=
1076 CRYPTO_MAX_ALG_NAME ||
1077 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1078 "rfc4543(%s)", alg->base.cra_driver_name) >=
1079 CRYPTO_MAX_ALG_NAME)
1080 goto err_free_inst;
1081
1082 inst->alg.base.cra_priority = alg->base.cra_priority;
1083 inst->alg.base.cra_blocksize = 1;
1084 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
1085
1086 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
1087
1088 inst->alg.ivsize = GCM_RFC4543_IV_SIZE;
1089 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
1090 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
1091
1092 inst->alg.init = crypto_rfc4543_init_tfm;
1093 inst->alg.exit = crypto_rfc4543_exit_tfm;
1094
1095 inst->alg.setkey = crypto_rfc4543_setkey;
1096 inst->alg.setauthsize = crypto_rfc4543_setauthsize;
1097 inst->alg.encrypt = crypto_rfc4543_encrypt;
1098 inst->alg.decrypt = crypto_rfc4543_decrypt;
1099
1100 inst->free = crypto_rfc4543_free;
1101
1102 err = aead_register_instance(tmpl, inst);
1103 if (err) {
1104err_free_inst:
1105 crypto_rfc4543_free(inst);
1106 }
1107 return err;
1108}
1109
1110static struct crypto_template crypto_gcm_tmpls[] = {
1111 {
1112 .name = "gcm_base",
1113 .create = crypto_gcm_base_create,
1114 .module = THIS_MODULE,
1115 }, {
1116 .name = "gcm",
1117 .create = crypto_gcm_create,
1118 .module = THIS_MODULE,
1119 }, {
1120 .name = "rfc4106",
1121 .create = crypto_rfc4106_create,
1122 .module = THIS_MODULE,
1123 }, {
1124 .name = "rfc4543",
1125 .create = crypto_rfc4543_create,
1126 .module = THIS_MODULE,
1127 },
1128};
1129
1130static int __init crypto_gcm_module_init(void)
1131{
1132 int err;
1133
1134 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
1135 if (!gcm_zeroes)
1136 return -ENOMEM;
1137
1138 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
1139
1140 err = crypto_register_templates(crypto_gcm_tmpls,
1141 ARRAY_SIZE(crypto_gcm_tmpls));
1142 if (err)
1143 kfree(gcm_zeroes);
1144
1145 return err;
1146}
1147
1148static void __exit crypto_gcm_module_exit(void)
1149{
1150 kfree(gcm_zeroes);
1151 crypto_unregister_templates(crypto_gcm_tmpls,
1152 ARRAY_SIZE(crypto_gcm_tmpls));
1153}
1154
1155subsys_initcall(crypto_gcm_module_init);
1156module_exit(crypto_gcm_module_exit);
1157
1158MODULE_LICENSE("GPL");
1159MODULE_DESCRIPTION("Galois/Counter Mode");
1160MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1161MODULE_ALIAS_CRYPTO("gcm_base");
1162MODULE_ALIAS_CRYPTO("rfc4106");
1163MODULE_ALIAS_CRYPTO("rfc4543");
1164MODULE_ALIAS_CRYPTO("gcm");