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)
155 return crypto_gcm_check_authsize(authsize);
158 static void crypto_gcm_init_common(struct aead_request *req)
160 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
161 __be32 counter = cpu_to_be32(1);
162 struct scatterlist *sg;
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);
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);
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);
183 static void crypto_gcm_init_crypt(struct aead_request *req,
184 unsigned int cryptlen)
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;
192 dst = req->src == req->dst ? pctx->src : pctx->dst;
194 skcipher_request_set_tfm(skreq, ctx->ctr);
195 skcipher_request_set_crypt(skreq, pctx->src, dst,
196 cryptlen + sizeof(pctx->auth_tag),
200 static inline unsigned int gcm_remain(unsigned int len)
203 return len ? 16 - len : 0;
206 static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
208 static int gcm_hash_update(struct aead_request *req,
209 crypto_completion_t compl,
210 struct scatterlist *src,
211 unsigned int len, u32 flags)
213 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
214 struct ahash_request *ahreq = &pctx->u.ahreq;
216 ahash_request_set_callback(ahreq, flags, compl, req);
217 ahash_request_set_crypt(ahreq, src, NULL, len);
219 return crypto_ahash_update(ahreq);
222 static int gcm_hash_remain(struct aead_request *req,
224 crypto_completion_t compl, u32 flags)
226 return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
229 static int gcm_hash_len(struct aead_request *req, u32 flags)
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;
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));
244 return crypto_ahash_finup(ahreq);
247 static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
249 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
250 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
252 return gctx->complete(req, flags);
255 static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
257 struct aead_request *req = areq->data;
262 err = gcm_hash_len_continue(req, 0);
263 if (err == -EINPROGRESS)
267 aead_request_complete(req, err);
270 static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
272 return gcm_hash_len(req, flags) ?:
273 gcm_hash_len_continue(req, flags);
276 static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
279 struct aead_request *req = areq->data;
284 err = gcm_hash_crypt_remain_continue(req, 0);
285 if (err == -EINPROGRESS)
289 aead_request_complete(req, err);
292 static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
294 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
295 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
298 remain = gcm_remain(gctx->cryptlen);
300 return gcm_hash_remain(req, remain,
301 gcm_hash_crypt_remain_done, flags) ?:
302 gcm_hash_crypt_remain_continue(req, flags);
304 return gcm_hash_crypt_remain_continue(req, flags);
307 static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
309 struct aead_request *req = areq->data;
314 err = gcm_hash_crypt_continue(req, 0);
315 if (err == -EINPROGRESS)
319 aead_request_complete(req, err);
322 static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
324 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
325 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
328 return gcm_hash_update(req, gcm_hash_crypt_done,
329 gctx->src, gctx->cryptlen, flags) ?:
330 gcm_hash_crypt_continue(req, flags);
332 return gcm_hash_crypt_remain_continue(req, flags);
335 static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
338 struct aead_request *req = areq->data;
343 err = gcm_hash_assoc_remain_continue(req, 0);
344 if (err == -EINPROGRESS)
348 aead_request_complete(req, err);
351 static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
355 remain = gcm_remain(req->assoclen);
357 return gcm_hash_remain(req, remain,
358 gcm_hash_assoc_remain_done, flags) ?:
359 gcm_hash_assoc_remain_continue(req, flags);
361 return gcm_hash_assoc_remain_continue(req, flags);
364 static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
366 struct aead_request *req = areq->data;
371 err = gcm_hash_assoc_continue(req, 0);
372 if (err == -EINPROGRESS)
376 aead_request_complete(req, err);
379 static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
382 return gcm_hash_update(req, gcm_hash_assoc_done,
383 req->src, req->assoclen, flags) ?:
384 gcm_hash_assoc_continue(req, flags);
386 return gcm_hash_assoc_remain_continue(req, flags);
389 static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
391 struct aead_request *req = areq->data;
396 err = gcm_hash_init_continue(req, 0);
397 if (err == -EINPROGRESS)
401 aead_request_complete(req, err);
404 static int gcm_hash(struct aead_request *req, u32 flags)
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));
410 ahash_request_set_tfm(ahreq, ctx->ghash);
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);
417 static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
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;
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);
430 static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
432 struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
433 struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
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;
439 return gcm_hash(req, flags);
442 static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
444 struct aead_request *req = areq->data;
449 err = gcm_encrypt_continue(req, 0);
450 if (err == -EINPROGRESS)
454 aead_request_complete(req, err);
457 static int crypto_gcm_encrypt(struct aead_request *req)
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);
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);
467 return crypto_skcipher_encrypt(skreq) ?:
468 gcm_encrypt_continue(req, flags);
471 static int crypto_gcm_verify(struct aead_request *req)
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;
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;
486 static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
488 struct aead_request *req = areq->data;
491 err = crypto_gcm_verify(req);
493 aead_request_complete(req, err);
496 static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
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;
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);
507 static int crypto_gcm_decrypt(struct aead_request *req)
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);
516 cryptlen -= authsize;
518 crypto_gcm_init_common(req);
520 gctx->src = sg_next(pctx->src);
521 gctx->cryptlen = cryptlen;
522 gctx->complete = gcm_dec_hash_continue;
524 return gcm_hash(req, flags);
527 static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
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;
537 ghash = crypto_spawn_ahash(&ictx->ghash);
539 return PTR_ERR(ghash);
541 ctr = crypto_spawn_skcipher(&ictx->ctr);
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)));
561 crypto_free_ahash(ghash);
565 static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
567 struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
569 crypto_free_ahash(ctx->ghash);
570 crypto_free_skcipher(ctx->ctr);
573 static void crypto_gcm_free(struct aead_instance *inst)
575 struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
577 crypto_drop_skcipher(&ctx->ctr);
578 crypto_drop_ahash(&ctx->ghash);
582 static int crypto_gcm_create_common(struct crypto_template *tmpl,
584 const char *ctr_name,
585 const char *ghash_name)
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;
595 algt = crypto_get_attr_type(tb);
597 return PTR_ERR(algt);
599 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
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,
607 if (IS_ERR(ghash_alg))
608 return PTR_ERR(ghash_alg);
610 ghash = __crypto_hash_alg_common(ghash_alg);
613 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
617 ctx = aead_instance_ctx(inst);
618 err = crypto_init_ahash_spawn(&ctx->ghash, ghash,
619 aead_crypto_instance(inst));
624 if (strcmp(ghash->base.cra_name, "ghash") != 0 ||
625 ghash->digestsize != 16)
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,
635 ctr = crypto_spawn_skcipher_alg(&ctx->ctr);
637 /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */
639 if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
640 crypto_skcipher_alg_ivsize(ctr) != 16 ||
641 ctr->base.cra_blocksize != 1)
645 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
646 "gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
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) >=
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;
673 inst->free = crypto_gcm_free;
675 err = aead_register_instance(tmpl, inst);
680 crypto_mod_put(ghash_alg);
684 crypto_drop_skcipher(&ctx->ctr);
686 crypto_drop_ahash(&ctx->ghash);
692 static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
694 const char *cipher_name;
695 char ctr_name[CRYPTO_MAX_ALG_NAME];
697 cipher_name = crypto_attr_alg_name(tb[1]);
698 if (IS_ERR(cipher_name))
699 return PTR_ERR(cipher_name);
701 if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
703 return -ENAMETOOLONG;
705 return crypto_gcm_create_common(tmpl, tb, ctr_name, "ghash");
708 static int crypto_gcm_base_create(struct crypto_template *tmpl,
711 const char *ctr_name;
712 const char *ghash_name;
714 ctr_name = crypto_attr_alg_name(tb[1]);
715 if (IS_ERR(ctr_name))
716 return PTR_ERR(ctr_name);
718 ghash_name = crypto_attr_alg_name(tb[2]);
719 if (IS_ERR(ghash_name))
720 return PTR_ERR(ghash_name);
722 return crypto_gcm_create_common(tmpl, tb, ctr_name, ghash_name);
725 static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
728 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
729 struct crypto_aead *child = ctx->child;
736 memcpy(ctx->nonce, key + keylen, 4);
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);
748 static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
749 unsigned int authsize)
751 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
754 err = crypto_rfc4106_check_authsize(authsize);
758 return crypto_aead_setauthsize(ctx->child, authsize);
761 static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
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);
772 scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0);
774 memcpy(iv, ctx->nonce, 4);
775 memcpy(iv + 4, req->iv, 8);
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);
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);
791 aead_request_set_tfm(subreq, child);
792 aead_request_set_callback(subreq, req->base.flags, req->base.complete,
794 aead_request_set_crypt(subreq, rctx->src,
795 req->src == req->dst ? rctx->src : rctx->dst,
797 aead_request_set_ad(subreq, req->assoclen - 8);
802 static int crypto_rfc4106_encrypt(struct aead_request *req)
806 err = crypto_ipsec_check_assoclen(req->assoclen);
810 req = crypto_rfc4106_crypt(req);
812 return crypto_aead_encrypt(req);
815 static int crypto_rfc4106_decrypt(struct aead_request *req)
819 err = crypto_ipsec_check_assoclen(req->assoclen);
823 req = crypto_rfc4106_crypt(req);
825 return crypto_aead_decrypt(req);
828 static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
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;
836 aead = crypto_spawn_aead(spawn);
838 return PTR_ERR(aead);
842 align = crypto_aead_alignmask(aead);
843 align &= ~(crypto_tfm_ctx_alignment() - 1);
844 crypto_aead_set_reqsize(
846 sizeof(struct crypto_rfc4106_req_ctx) +
847 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
853 static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
855 struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
857 crypto_free_aead(ctx->child);
860 static void crypto_rfc4106_free(struct aead_instance *inst)
862 crypto_drop_aead(aead_instance_ctx(inst));
866 static int crypto_rfc4106_create(struct crypto_template *tmpl,
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;
876 algt = crypto_get_attr_type(tb);
878 return PTR_ERR(algt);
880 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
883 ccm_name = crypto_attr_alg_name(tb[1]);
884 if (IS_ERR(ccm_name))
885 return PTR_ERR(ccm_name);
887 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
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));
898 alg = crypto_spawn_aead_alg(spawn);
902 /* Underlying IV size must be 12. */
903 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
906 /* Not a stream cipher? */
907 if (alg->base.cra_blocksize != 1)
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) >=
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;
924 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
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);
930 inst->alg.init = crypto_rfc4106_init_tfm;
931 inst->alg.exit = crypto_rfc4106_exit_tfm;
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;
938 inst->free = crypto_rfc4106_free;
940 err = aead_register_instance(tmpl, inst);
948 crypto_drop_aead(spawn);
954 static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
957 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
958 struct crypto_aead *child = ctx->child;
965 memcpy(ctx->nonce, key + keylen, 4);
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);
977 static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
978 unsigned int authsize)
980 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
985 return crypto_aead_setauthsize(ctx->child, authsize);
988 static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
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);
999 if (req->src != req->dst) {
1000 err = crypto_rfc4543_copy_src_to_dst(req, enc);
1005 memcpy(iv, ctx->nonce, 4);
1006 memcpy(iv + 4, req->iv, 8);
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 -
1016 return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
1019 static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
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);
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);
1032 return crypto_skcipher_encrypt(nreq);
1035 static int crypto_rfc4543_encrypt(struct aead_request *req)
1037 return crypto_ipsec_check_assoclen(req->assoclen) ?:
1038 crypto_rfc4543_crypt(req, true);
1041 static int crypto_rfc4543_decrypt(struct aead_request *req)
1043 return crypto_ipsec_check_assoclen(req->assoclen) ?:
1044 crypto_rfc4543_crypt(req, false);
1047 static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
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;
1058 aead = crypto_spawn_aead(spawn);
1060 return PTR_ERR(aead);
1062 null = crypto_get_default_null_skcipher();
1063 err = PTR_ERR(null);
1070 align = crypto_aead_alignmask(aead);
1071 align &= ~(crypto_tfm_ctx_alignment() - 1);
1072 crypto_aead_set_reqsize(
1074 sizeof(struct crypto_rfc4543_req_ctx) +
1075 ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
1076 align + GCM_AES_IV_SIZE);
1081 crypto_free_aead(aead);
1085 static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
1087 struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
1089 crypto_free_aead(ctx->child);
1090 crypto_put_default_null_skcipher();
1093 static void crypto_rfc4543_free(struct aead_instance *inst)
1095 struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst);
1097 crypto_drop_aead(&ctx->aead);
1102 static int crypto_rfc4543_create(struct crypto_template *tmpl,
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;
1113 algt = crypto_get_attr_type(tb);
1115 return PTR_ERR(algt);
1117 if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
1120 ccm_name = crypto_attr_alg_name(tb[1]);
1121 if (IS_ERR(ccm_name))
1122 return PTR_ERR(ccm_name);
1124 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
1128 ctx = aead_instance_ctx(inst);
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));
1136 alg = crypto_spawn_aead_alg(spawn);
1140 /* Underlying IV size must be 12. */
1141 if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
1144 /* Not a stream cipher? */
1145 if (alg->base.cra_blocksize != 1)
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)
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;
1162 inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
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);
1168 inst->alg.init = crypto_rfc4543_init_tfm;
1169 inst->alg.exit = crypto_rfc4543_exit_tfm;
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;
1176 inst->free = crypto_rfc4543_free,
1178 err = aead_register_instance(tmpl, inst);
1186 crypto_drop_aead(spawn);
1192 static struct crypto_template crypto_gcm_tmpls[] = {
1195 .create = crypto_gcm_base_create,
1196 .module = THIS_MODULE,
1199 .create = crypto_gcm_create,
1200 .module = THIS_MODULE,
1203 .create = crypto_rfc4106_create,
1204 .module = THIS_MODULE,
1207 .create = crypto_rfc4543_create,
1208 .module = THIS_MODULE,
1212 static int __init crypto_gcm_module_init(void)
1216 gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
1220 sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
1222 err = crypto_register_templates(crypto_gcm_tmpls,
1223 ARRAY_SIZE(crypto_gcm_tmpls));
1230 static void __exit crypto_gcm_module_exit(void)
1233 crypto_unregister_templates(crypto_gcm_tmpls,
1234 ARRAY_SIZE(crypto_gcm_tmpls));
1237 subsys_initcall(crypto_gcm_module_init);
1238 module_exit(crypto_gcm_module_exit);
1240 MODULE_LICENSE("GPL");
1241 MODULE_DESCRIPTION("Galois/Counter Mode");
1242 MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
1243 MODULE_ALIAS_CRYPTO("gcm_base");
1244 MODULE_ALIAS_CRYPTO("rfc4106");
1245 MODULE_ALIAS_CRYPTO("rfc4543");
1246 MODULE_ALIAS_CRYPTO("gcm");