1 // SPDX-License-Identifier: GPL-2.0-only
3 * GCM: Galois/Counter Mode.
5 * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
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>
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>
23 struct gcm_instance_ctx {
24 struct crypto_skcipher_spawn ctr;
25 struct crypto_ahash_spawn ghash;
28 struct crypto_gcm_ctx {
29 struct crypto_skcipher *ctr;
30 struct crypto_ahash *ghash;
33 struct crypto_rfc4106_ctx {
34 struct crypto_aead *child;
38 struct crypto_rfc4106_req_ctx {
39 struct scatterlist src[3];
40 struct scatterlist dst[3];
41 struct aead_request subreq;
44 struct crypto_rfc4543_instance_ctx {
45 struct crypto_aead_spawn aead;
48 struct crypto_rfc4543_ctx {
49 struct crypto_aead *child;
50 struct crypto_sync_skcipher *null;
54 struct crypto_rfc4543_req_ctx {
55 struct aead_request subreq;
58 struct crypto_gcm_ghash_ctx {
59 unsigned int cryptlen;
60 struct scatterlist *src;
61 int (*complete)(struct aead_request *req, u32 flags);
64 struct crypto_gcm_req_priv_ctx {
68 struct scatterlist src[3];
69 struct scatterlist dst[3];
70 struct scatterlist sg;
71 struct crypto_gcm_ghash_ctx ghash_ctx;
73 struct ahash_request ahreq;
74 struct skcipher_request skreq;
80 struct scatterlist sg;
83 static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
85 static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
86 struct aead_request *req)
88 unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
90 return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
93 static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
96 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
97 struct crypto_ahash *ghash = ctx->ghash;
98 struct crypto_skcipher *ctr = ctx->ctr;
103 struct crypto_wait wait;
105 struct scatterlist sg[1];
106 struct skcipher_request req;
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);
119 data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr),
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,
131 skcipher_request_set_crypt(&data->req, data->sg, data->sg,
132 sizeof(data->hash), data->iv);
134 err = crypto_wait_req(crypto_skcipher_encrypt(&data->req),
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);
152 static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
153 unsigned int authsize)
171 static void crypto_gcm_init_common(struct aead_request *req)
173 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
174 __be32 counter = cpu_to_be32(1);
175 struct scatterlist *sg;
177 memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
178 memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE);
179 memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4);
181 sg_init_table(pctx->src, 3);
182 sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
183 sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
184 if (sg != pctx->src + 1)
185 sg_chain(pctx->src, 2, sg);
187 if (req->src != req->dst) {
188 sg_init_table(pctx->dst, 3);
189 sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
190 sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
191 if (sg != pctx->dst + 1)
192 sg_chain(pctx->dst, 2, sg);
196 static void crypto_gcm_init_crypt(struct aead_request *req,
197 unsigned int cryptlen)
199 struct crypto_aead *aead = crypto_aead_reqtfm(req);
200 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
201 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
202 struct skcipher_request *skreq = &pctx->u.skreq;
203 struct scatterlist *dst;
205 dst = req->src == req->dst ? pctx->src : pctx->dst;
207 skcipher_request_set_tfm(skreq, ctx->ctr);
208 skcipher_request_set_crypt(skreq, pctx->src, dst,
209 cryptlen + sizeof(pctx->auth_tag),
213 static inline unsigned int gcm_remain(unsigned int len)
216 return len ? 16 - len : 0;
219 static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
221 static int gcm_hash_update(struct aead_request *req,
222 crypto_completion_t compl,
223 struct scatterlist *src,
224 unsigned int len, u32 flags)
226 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
227 struct ahash_request *ahreq = &pctx->u.ahreq;
229 ahash_request_set_callback(ahreq, flags, compl, req);
230 ahash_request_set_crypt(ahreq, src, NULL, len);
232 return crypto_ahash_update(ahreq);
235 static int gcm_hash_remain(struct aead_request *req,
237 crypto_completion_t compl, u32 flags)
239 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
242 static int gcm_hash_len(struct aead_request *req, u32 flags)
244 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
245 struct ahash_request *ahreq = &pctx->u.ahreq;
246 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
249 lengths.a = cpu_to_be64(req->assoclen * 8);
250 lengths.b = cpu_to_be64(gctx->cryptlen * 8);
251 memcpy(pctx->iauth_tag, &lengths, 16);
252 sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
253 ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
254 ahash_request_set_crypt(ahreq, &pctx->sg,
255 pctx->iauth_tag, sizeof(lengths));
257 return crypto_ahash_finup(ahreq);
260 static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
262 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
263 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
265 return gctx->complete(req, flags);
268 static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
270 struct aead_request *req = areq->data;
275 err = gcm_hash_len_continue(req, 0);
276 if (err == -EINPROGRESS)
280 aead_request_complete(req, err);
283 static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
285 return gcm_hash_len(req, flags) ?:
286 gcm_hash_len_continue(req, flags);
289 static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
292 struct aead_request *req = areq->data;
297 err = gcm_hash_crypt_remain_continue(req, 0);
298 if (err == -EINPROGRESS)
302 aead_request_complete(req, err);
305 static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
307 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
308 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
311 remain = gcm_remain(gctx->cryptlen);
313 return gcm_hash_remain(req, remain,
314 gcm_hash_crypt_remain_done, flags) ?:
315 gcm_hash_crypt_remain_continue(req, flags);
317 return gcm_hash_crypt_remain_continue(req, flags);
320 static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
322 struct aead_request *req = areq->data;
327 err = gcm_hash_crypt_continue(req, 0);
328 if (err == -EINPROGRESS)
332 aead_request_complete(req, err);
335 static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
337 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
338 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
341 return gcm_hash_update(req, gcm_hash_crypt_done,
342 gctx->src, gctx->cryptlen, flags) ?:
343 gcm_hash_crypt_continue(req, flags);
345 return gcm_hash_crypt_remain_continue(req, flags);
348 static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
351 struct aead_request *req = areq->data;
356 err = gcm_hash_assoc_remain_continue(req, 0);
357 if (err == -EINPROGRESS)
361 aead_request_complete(req, err);
364 static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
368 remain = gcm_remain(req->assoclen);
370 return gcm_hash_remain(req, remain,
371 gcm_hash_assoc_remain_done, flags) ?:
372 gcm_hash_assoc_remain_continue(req, flags);
374 return gcm_hash_assoc_remain_continue(req, flags);
377 static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
379 struct aead_request *req = areq->data;
384 err = gcm_hash_assoc_continue(req, 0);
385 if (err == -EINPROGRESS)
389 aead_request_complete(req, err);
392 static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
395 return gcm_hash_update(req, gcm_hash_assoc_done,
396 req->src, req->assoclen, flags) ?:
397 gcm_hash_assoc_continue(req, flags);
399 return gcm_hash_assoc_remain_continue(req, flags);
402 static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
404 struct aead_request *req = areq->data;
409 err = gcm_hash_init_continue(req, 0);
410 if (err == -EINPROGRESS)
414 aead_request_complete(req, err);
417 static int gcm_hash(struct aead_request *req, u32 flags)
419 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
420 struct ahash_request *ahreq = &pctx->u.ahreq;
421 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
423 ahash_request_set_tfm(ahreq, ctx->ghash);
425 ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
426 return crypto_ahash_init(ahreq) ?:
427 gcm_hash_init_continue(req, flags);
430 static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
432 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
433 struct crypto_aead *aead = crypto_aead_reqtfm(req);
434 u8 *auth_tag = pctx->auth_tag;
436 crypto_xor(auth_tag, pctx->iauth_tag, 16);
437 scatterwalk_map_and_copy(auth_tag, req->dst,
438 req->assoclen + req->cryptlen,
439 crypto_aead_authsize(aead), 1);
443 static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
445 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
446 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
448 gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
449 gctx->cryptlen = req->cryptlen;
450 gctx->complete = gcm_enc_copy_hash;
452 return gcm_hash(req, flags);
455 static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
457 struct aead_request *req = areq->data;
462 err = gcm_encrypt_continue(req, 0);
463 if (err == -EINPROGRESS)
467 aead_request_complete(req, err);
470 static int crypto_gcm_encrypt(struct aead_request *req)
472 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
473 struct skcipher_request *skreq = &pctx->u.skreq;
474 u32 flags = aead_request_flags(req);
476 crypto_gcm_init_common(req);
477 crypto_gcm_init_crypt(req, req->cryptlen);
478 skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req);
480 return crypto_skcipher_encrypt(skreq) ?:
481 gcm_encrypt_continue(req, flags);
484 static int crypto_gcm_verify(struct aead_request *req)
486 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
487 struct crypto_aead *aead = crypto_aead_reqtfm(req);
488 u8 *auth_tag = pctx->auth_tag;
489 u8 *iauth_tag = pctx->iauth_tag;
490 unsigned int authsize = crypto_aead_authsize(aead);
491 unsigned int cryptlen = req->cryptlen - authsize;
493 crypto_xor(auth_tag, iauth_tag, 16);
494 scatterwalk_map_and_copy(iauth_tag, req->src,
495 req->assoclen + cryptlen, authsize, 0);
496 return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
499 static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
501 struct aead_request *req = areq->data;
504 err = crypto_gcm_verify(req);
506 aead_request_complete(req, err);
509 static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
511 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
512 struct skcipher_request *skreq = &pctx->u.skreq;
513 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
515 crypto_gcm_init_crypt(req, gctx->cryptlen);
516 skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req);
517 return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req);
520 static int crypto_gcm_decrypt(struct aead_request *req)
522 struct crypto_aead *aead = crypto_aead_reqtfm(req);
523 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
524 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
525 unsigned int authsize = crypto_aead_authsize(aead);
526 unsigned int cryptlen = req->cryptlen;
527 u32 flags = aead_request_flags(req);
529 cryptlen -= authsize;
531 crypto_gcm_init_common(req);
533 gctx->src = sg_next(pctx->src);
534 gctx->cryptlen = cryptlen;
535 gctx->complete = gcm_dec_hash_continue;
537 return gcm_hash(req, flags);
540 static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
542 struct aead_instance *inst = aead_alg_instance(tfm);
543 struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
544 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
545 struct crypto_skcipher *ctr;
546 struct crypto_ahash *ghash;
550 ghash = crypto_spawn_ahash(&ictx->ghash);
552 return PTR_ERR(ghash);
554 ctr = crypto_spawn_skcipher(&ictx->ctr);
562 align = crypto_aead_alignmask(tfm);
563 align &= ~(crypto_tfm_ctx_alignment() - 1);
564 crypto_aead_set_reqsize(tfm,
565 align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
566 max(sizeof(struct skcipher_request) +
567 crypto_skcipher_reqsize(ctr),
568 sizeof(struct ahash_request) +
569 crypto_ahash_reqsize(ghash)));
574 crypto_free_ahash(ghash);
578 static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
580 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
582 crypto_free_ahash(ctx->ghash);
583 crypto_free_skcipher(ctx->ctr);
586 static void crypto_gcm_free(struct aead_instance *inst)
588 struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
590 crypto_drop_skcipher(&ctx->ctr);
591 crypto_drop_ahash(&ctx->ghash);
595 static int crypto_gcm_create_common(struct crypto_template *tmpl,
597 const char *ctr_name,
598 const char *ghash_name)
600 struct crypto_attr_type *algt;
601 struct aead_instance *inst;
602 struct skcipher_alg *ctr;
603 struct crypto_alg *ghash_alg;
604 struct hash_alg_common *ghash;
605 struct gcm_instance_ctx *ctx;
608 algt = crypto_get_attr_type(tb);
610 return PTR_ERR(algt);
612 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
615 ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
616 CRYPTO_ALG_TYPE_HASH,
617 CRYPTO_ALG_TYPE_AHASH_MASK |
618 crypto_requires_sync(algt->type,
620 if (IS_ERR(ghash_alg))
621 return PTR_ERR(ghash_alg);
623 ghash = __crypto_hash_alg_common(ghash_alg);
626 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
630 ctx = aead_instance_ctx(inst);
631 err = crypto_init_ahash_spawn(&ctx->ghash, ghash,
632 aead_crypto_instance(inst));
637 if (strcmp(ghash->base.cra_name, "ghash") != 0 ||
638 ghash->digestsize != 16)
641 crypto_set_skcipher_spawn(&ctx->ctr, aead_crypto_instance(inst));
642 err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
643 crypto_requires_sync(algt->type,
648 ctr = crypto_spawn_skcipher_alg(&ctx->ctr);
650 /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */
652 if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
653 crypto_skcipher_alg_ivsize(ctr) != 16 ||
654 ctr->base.cra_blocksize != 1)
658 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
659 "gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
662 if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
663 "gcm_base(%s,%s)", ctr->base.cra_driver_name,
664 ghash_alg->cra_driver_name) >=
668 inst->alg.base.cra_flags = (ghash->base.cra_flags |
669 ctr->base.cra_flags) & CRYPTO_ALG_ASYNC;
670 inst->alg.base.cra_priority = (ghash->base.cra_priority +
671 ctr->base.cra_priority) / 2;
672 inst->alg.base.cra_blocksize = 1;
673 inst->alg.base.cra_alignmask = ghash->base.cra_alignmask |
674 ctr->base.cra_alignmask;
675 inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
676 inst->alg.ivsize = GCM_AES_IV_SIZE;
677 inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
678 inst->alg.maxauthsize = 16;
679 inst->alg.init = crypto_gcm_init_tfm;
680 inst->alg.exit = crypto_gcm_exit_tfm;
681 inst->alg.setkey = crypto_gcm_setkey;
682 inst->alg.setauthsize = crypto_gcm_setauthsize;
683 inst->alg.encrypt = crypto_gcm_encrypt;
684 inst->alg.decrypt = crypto_gcm_decrypt;
686 inst->free = crypto_gcm_free;
688 err = aead_register_instance(tmpl, inst);
693 crypto_mod_put(ghash_alg);
697 crypto_drop_skcipher(&ctx->ctr);
699 crypto_drop_ahash(&ctx->ghash);
705 static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
707 const char *cipher_name;
708 char ctr_name[CRYPTO_MAX_ALG_NAME];
710 cipher_name = crypto_attr_alg_name(tb[1]);
711 if (IS_ERR(cipher_name))
712 return PTR_ERR(cipher_name);
714 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
716 return -ENAMETOOLONG;
718 return crypto_gcm_create_common(tmpl, tb, ctr_name, "ghash");
721 static int crypto_gcm_base_create(struct crypto_template *tmpl,
724 const char *ctr_name;
725 const char *ghash_name;
727 ctr_name = crypto_attr_alg_name(tb[1]);
728 if (IS_ERR(ctr_name))
729 return PTR_ERR(ctr_name);
731 ghash_name = crypto_attr_alg_name(tb[2]);
732 if (IS_ERR(ghash_name))
733 return PTR_ERR(ghash_name);
735 return crypto_gcm_create_common(tmpl, tb, ctr_name, ghash_name);
738 static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
741 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
742 struct crypto_aead *child = ctx->child;
749 memcpy(ctx->nonce, key + keylen, 4);
751 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
752 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
753 CRYPTO_TFM_REQ_MASK);
754 err = crypto_aead_setkey(child, key, keylen);
755 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
756 CRYPTO_TFM_RES_MASK);
761 static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
762 unsigned int authsize)
764 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
775 return crypto_aead_setauthsize(ctx->child, authsize);
778 static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
780 struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req);
781 struct crypto_aead *aead = crypto_aead_reqtfm(req);
782 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
783 struct aead_request *subreq = &rctx->subreq;
784 struct crypto_aead *child = ctx->child;
785 struct scatterlist *sg;
786 u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
787 crypto_aead_alignmask(child) + 1);
789 scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0);
791 memcpy(iv, ctx->nonce, 4);
792 memcpy(iv + 4, req->iv, 8);
794 sg_init_table(rctx->src, 3);
795 sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
796 sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
797 if (sg != rctx->src + 1)
798 sg_chain(rctx->src, 2, sg);
800 if (req->src != req->dst) {
801 sg_init_table(rctx->dst, 3);
802 sg_set_buf(rctx->dst, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
803 sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
804 if (sg != rctx->dst + 1)
805 sg_chain(rctx->dst, 2, sg);
808 aead_request_set_tfm(subreq, child);
809 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
811 aead_request_set_crypt(subreq, rctx->src,
812 req->src == req->dst ? rctx->src : rctx->dst,
814 aead_request_set_ad(subreq, req->assoclen - 8);
819 static int crypto_rfc4106_encrypt(struct aead_request *req)
821 if (req->assoclen != 16 && req->assoclen != 20)
824 req = crypto_rfc4106_crypt(req);
826 return crypto_aead_encrypt(req);
829 static int crypto_rfc4106_decrypt(struct aead_request *req)
831 if (req->assoclen != 16 && req->assoclen != 20)
834 req = crypto_rfc4106_crypt(req);
836 return crypto_aead_decrypt(req);
839 static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
841 struct aead_instance *inst = aead_alg_instance(tfm);
842 struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
843 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
844 struct crypto_aead *aead;
847 aead = crypto_spawn_aead(spawn);
849 return PTR_ERR(aead);
853 align = crypto_aead_alignmask(aead);
854 align &= ~(crypto_tfm_ctx_alignment() - 1);
855 crypto_aead_set_reqsize(
857 sizeof(struct crypto_rfc4106_req_ctx) +
858 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
864 static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
866 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
868 crypto_free_aead(ctx->child);
871 static void crypto_rfc4106_free(struct aead_instance *inst)
873 crypto_drop_aead(aead_instance_ctx(inst));
877 static int crypto_rfc4106_create(struct crypto_template *tmpl,
880 struct crypto_attr_type *algt;
881 struct aead_instance *inst;
882 struct crypto_aead_spawn *spawn;
883 struct aead_alg *alg;
884 const char *ccm_name;
887 algt = crypto_get_attr_type(tb);
889 return PTR_ERR(algt);
891 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
894 ccm_name = crypto_attr_alg_name(tb[1]);
895 if (IS_ERR(ccm_name))
896 return PTR_ERR(ccm_name);
898 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
902 spawn = aead_instance_ctx(inst);
903 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
904 err = crypto_grab_aead(spawn, ccm_name, 0,
905 crypto_requires_sync(algt->type, algt->mask));
909 alg = crypto_spawn_aead_alg(spawn);
913 /* Underlying IV size must be 12. */
914 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
917 /* Not a stream cipher? */
918 if (alg->base.cra_blocksize != 1)
922 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
923 "rfc4106(%s)", alg->base.cra_name) >=
924 CRYPTO_MAX_ALG_NAME ||
925 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
926 "rfc4106(%s)", alg->base.cra_driver_name) >=
930 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
931 inst->alg.base.cra_priority = alg->base.cra_priority;
932 inst->alg.base.cra_blocksize = 1;
933 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
935 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
937 inst->alg.ivsize = GCM_RFC4106_IV_SIZE;
938 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
939 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
941 inst->alg.init = crypto_rfc4106_init_tfm;
942 inst->alg.exit = crypto_rfc4106_exit_tfm;
944 inst->alg.setkey = crypto_rfc4106_setkey;
945 inst->alg.setauthsize = crypto_rfc4106_setauthsize;
946 inst->alg.encrypt = crypto_rfc4106_encrypt;
947 inst->alg.decrypt = crypto_rfc4106_decrypt;
949 inst->free = crypto_rfc4106_free;
951 err = aead_register_instance(tmpl, inst);
959 crypto_drop_aead(spawn);
965 static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
968 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
969 struct crypto_aead *child = ctx->child;
976 memcpy(ctx->nonce, key + keylen, 4);
978 crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
979 crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
980 CRYPTO_TFM_REQ_MASK);
981 err = crypto_aead_setkey(child, key, keylen);
982 crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
983 CRYPTO_TFM_RES_MASK);
988 static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
989 unsigned int authsize)
991 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
996 return crypto_aead_setauthsize(ctx->child, authsize);
999 static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
1001 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1002 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1003 struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
1004 struct aead_request *subreq = &rctx->subreq;
1005 unsigned int authsize = crypto_aead_authsize(aead);
1006 u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
1007 crypto_aead_alignmask(ctx->child) + 1);
1010 if (req->src != req->dst) {
1011 err = crypto_rfc4543_copy_src_to_dst(req, enc);
1016 memcpy(iv, ctx->nonce, 4);
1017 memcpy(iv + 4, req->iv, 8);
1019 aead_request_set_tfm(subreq, ctx->child);
1020 aead_request_set_callback(subreq, req->base.flags,
1021 req->base.complete, req->base.data);
1022 aead_request_set_crypt(subreq, req->src, req->dst,
1023 enc ? 0 : authsize, iv);
1024 aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
1027 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
1030 static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
1032 struct crypto_aead *aead = crypto_aead_reqtfm(req);
1033 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
1034 unsigned int authsize = crypto_aead_authsize(aead);
1035 unsigned int nbytes = req->assoclen + req->cryptlen -
1036 (enc ? 0 : authsize);
1037 SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null);
1039 skcipher_request_set_sync_tfm(nreq, ctx->null);
1040 skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL);
1041 skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL);
1043 return crypto_skcipher_encrypt(nreq);
1046 static int crypto_rfc4543_encrypt(struct aead_request *req)
1048 return crypto_rfc4543_crypt(req, true);
1051 static int crypto_rfc4543_decrypt(struct aead_request *req)
1053 return crypto_rfc4543_crypt(req, false);
1056 static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
1058 struct aead_instance *inst = aead_alg_instance(tfm);
1059 struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst);
1060 struct crypto_aead_spawn *spawn = &ictx->aead;
1061 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1062 struct crypto_aead *aead;
1063 struct crypto_sync_skcipher *null;
1064 unsigned long align;
1067 aead = crypto_spawn_aead(spawn);
1069 return PTR_ERR(aead);
1071 null = crypto_get_default_null_skcipher();
1072 err = PTR_ERR(null);
1079 align = crypto_aead_alignmask(aead);
1080 align &= ~(crypto_tfm_ctx_alignment() - 1);
1081 crypto_aead_set_reqsize(
1083 sizeof(struct crypto_rfc4543_req_ctx) +
1084 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
1085 align + GCM_AES_IV_SIZE);
1090 crypto_free_aead(aead);
1094 static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
1096 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1098 crypto_free_aead(ctx->child);
1099 crypto_put_default_null_skcipher();
1102 static void crypto_rfc4543_free(struct aead_instance *inst)
1104 struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst);
1106 crypto_drop_aead(&ctx->aead);
1111 static int crypto_rfc4543_create(struct crypto_template *tmpl,
1114 struct crypto_attr_type *algt;
1115 struct aead_instance *inst;
1116 struct crypto_aead_spawn *spawn;
1117 struct aead_alg *alg;
1118 struct crypto_rfc4543_instance_ctx *ctx;
1119 const char *ccm_name;
1122 algt = crypto_get_attr_type(tb);
1124 return PTR_ERR(algt);
1126 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
1129 ccm_name = crypto_attr_alg_name(tb[1]);
1130 if (IS_ERR(ccm_name))
1131 return PTR_ERR(ccm_name);
1133 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1137 ctx = aead_instance_ctx(inst);
1139 crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
1140 err = crypto_grab_aead(spawn, ccm_name, 0,
1141 crypto_requires_sync(algt->type, algt->mask));
1145 alg = crypto_spawn_aead_alg(spawn);
1149 /* Underlying IV size must be 12. */
1150 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
1153 /* Not a stream cipher? */
1154 if (alg->base.cra_blocksize != 1)
1157 err = -ENAMETOOLONG;
1158 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
1159 "rfc4543(%s)", alg->base.cra_name) >=
1160 CRYPTO_MAX_ALG_NAME ||
1161 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
1162 "rfc4543(%s)", alg->base.cra_driver_name) >=
1163 CRYPTO_MAX_ALG_NAME)
1166 inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
1167 inst->alg.base.cra_priority = alg->base.cra_priority;
1168 inst->alg.base.cra_blocksize = 1;
1169 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
1171 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
1173 inst->alg.ivsize = GCM_RFC4543_IV_SIZE;
1174 inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
1175 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
1177 inst->alg.init = crypto_rfc4543_init_tfm;
1178 inst->alg.exit = crypto_rfc4543_exit_tfm;
1180 inst->alg.setkey = crypto_rfc4543_setkey;
1181 inst->alg.setauthsize = crypto_rfc4543_setauthsize;
1182 inst->alg.encrypt = crypto_rfc4543_encrypt;
1183 inst->alg.decrypt = crypto_rfc4543_decrypt;
1185 inst->free = crypto_rfc4543_free,
1187 err = aead_register_instance(tmpl, inst);
1195 crypto_drop_aead(spawn);
1201 static struct crypto_template crypto_gcm_tmpls[] = {
1204 .create = crypto_gcm_base_create,
1205 .module = THIS_MODULE,
1208 .create = crypto_gcm_create,
1209 .module = THIS_MODULE,
1212 .create = crypto_rfc4106_create,
1213 .module = THIS_MODULE,
1216 .create = crypto_rfc4543_create,
1217 .module = THIS_MODULE,
1221 static int __init crypto_gcm_module_init(void)
1225 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
1229 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
1231 err = crypto_register_templates(crypto_gcm_tmpls,
1232 ARRAY_SIZE(crypto_gcm_tmpls));
1239 static void __exit crypto_gcm_module_exit(void)
1242 crypto_unregister_templates(crypto_gcm_tmpls,
1243 ARRAY_SIZE(crypto_gcm_tmpls));
1246 subsys_initcall(crypto_gcm_module_init);
1247 module_exit(crypto_gcm_module_exit);
1249 MODULE_LICENSE("GPL");
1250 MODULE_DESCRIPTION("Galois/Counter Mode");
1251 MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1252 MODULE_ALIAS_CRYPTO("gcm_base");
1253 MODULE_ALIAS_CRYPTO("rfc4106");
1254 MODULE_ALIAS_CRYPTO("rfc4543");
1255 MODULE_ALIAS_CRYPTO("gcm");