diff options
Diffstat (limited to 'crypto')
-rw-r--r-- | crypto/Kconfig | 23 | ||||
-rw-r--r-- | crypto/Makefile | 8 | ||||
-rw-r--r-- | crypto/ablk_helper.c | 150 | ||||
-rw-r--r-- | crypto/ablkcipher.c | 21 | ||||
-rw-r--r-- | crypto/ansi_cprng.c | 4 | ||||
-rw-r--r-- | crypto/asymmetric_keys/rsa.c | 5 | ||||
-rw-r--r-- | crypto/authenc.c | 54 | ||||
-rw-r--r-- | crypto/authencesn.c | 34 | ||||
-rw-r--r-- | crypto/ccm.c | 4 | ||||
-rw-r--r-- | crypto/gcm.c | 2 | ||||
-rw-r--r-- | crypto/memneq.c | 138 |
11 files changed, 356 insertions, 87 deletions
diff --git a/crypto/Kconfig b/crypto/Kconfig index 4ae5734fb473..7bcb70d216e1 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -174,9 +174,8 @@ config CRYPTO_TEST help Quick & dirty crypto test module. -config CRYPTO_ABLK_HELPER_X86 +config CRYPTO_ABLK_HELPER tristate - depends on X86 select CRYPTO_CRYPTD config CRYPTO_GLUE_HELPER_X86 @@ -695,7 +694,7 @@ config CRYPTO_AES_NI_INTEL select CRYPTO_AES_X86_64 if 64BIT select CRYPTO_AES_586 if !64BIT select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_ALGAPI select CRYPTO_GLUE_HELPER_X86 if 64BIT select CRYPTO_LRW @@ -895,7 +894,7 @@ config CRYPTO_CAMELLIA_AESNI_AVX_X86_64 depends on CRYPTO select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_GLUE_HELPER_X86 select CRYPTO_CAMELLIA_X86_64 select CRYPTO_LRW @@ -917,7 +916,7 @@ config CRYPTO_CAMELLIA_AESNI_AVX2_X86_64 depends on CRYPTO select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_GLUE_HELPER_X86 select CRYPTO_CAMELLIA_X86_64 select CRYPTO_CAMELLIA_AESNI_AVX_X86_64 @@ -969,7 +968,7 @@ config CRYPTO_CAST5_AVX_X86_64 depends on X86 && 64BIT select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_CAST_COMMON select CRYPTO_CAST5 help @@ -992,7 +991,7 @@ config CRYPTO_CAST6_AVX_X86_64 depends on X86 && 64BIT select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_GLUE_HELPER_X86 select CRYPTO_CAST_COMMON select CRYPTO_CAST6 @@ -1110,7 +1109,7 @@ config CRYPTO_SERPENT_SSE2_X86_64 depends on X86 && 64BIT select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_GLUE_HELPER_X86 select CRYPTO_SERPENT select CRYPTO_LRW @@ -1132,7 +1131,7 @@ config CRYPTO_SERPENT_SSE2_586 depends on X86 && !64BIT select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_GLUE_HELPER_X86 select CRYPTO_SERPENT select CRYPTO_LRW @@ -1154,7 +1153,7 @@ config CRYPTO_SERPENT_AVX_X86_64 depends on X86 && 64BIT select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_GLUE_HELPER_X86 select CRYPTO_SERPENT select CRYPTO_LRW @@ -1176,7 +1175,7 @@ config CRYPTO_SERPENT_AVX2_X86_64 depends on X86 && 64BIT select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_GLUE_HELPER_X86 select CRYPTO_SERPENT select CRYPTO_SERPENT_AVX_X86_64 @@ -1292,7 +1291,7 @@ config CRYPTO_TWOFISH_AVX_X86_64 depends on X86 && 64BIT select CRYPTO_ALGAPI select CRYPTO_CRYPTD - select CRYPTO_ABLK_HELPER_X86 + select CRYPTO_ABLK_HELPER select CRYPTO_GLUE_HELPER_X86 select CRYPTO_TWOFISH_COMMON select CRYPTO_TWOFISH_X86_64 diff --git a/crypto/Makefile b/crypto/Makefile index b3a7e807e08b..989c510da8cc 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -2,8 +2,13 @@ # Cryptographic API # +# memneq MUST be built with -Os or -O0 to prevent early-return optimizations +# that will defeat memneq's actual purpose to prevent timing attacks. +CFLAGS_REMOVE_memneq.o := -O1 -O2 -O3 +CFLAGS_memneq.o := -Os + obj-$(CONFIG_CRYPTO) += crypto.o -crypto-y := api.o cipher.o compress.o +crypto-y := api.o cipher.o compress.o memneq.o obj-$(CONFIG_CRYPTO_WORKQUEUE) += crypto_wq.o @@ -105,3 +110,4 @@ obj-$(CONFIG_XOR_BLOCKS) += xor.o obj-$(CONFIG_ASYNC_CORE) += async_tx/ obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys/ obj-$(CONFIG_CRYPTO_HASH_INFO) += hash_info.o +obj-$(CONFIG_CRYPTO_ABLK_HELPER) += ablk_helper.o diff --git a/crypto/ablk_helper.c b/crypto/ablk_helper.c new file mode 100644 index 000000000000..ffe7278d4bd8 --- /dev/null +++ b/crypto/ablk_helper.c @@ -0,0 +1,150 @@ +/* + * Shared async block cipher helpers + * + * Copyright (c) 2012 Jussi Kivilinna <jussi.kivilinna@mbnet.fi> + * + * Based on aesni-intel_glue.c by: + * Copyright (C) 2008, Intel Corp. + * Author: Huang Ying <ying.huang@intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 + * USA + * + */ + +#include <linux/kernel.h> +#include <linux/crypto.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/hardirq.h> +#include <crypto/algapi.h> +#include <crypto/cryptd.h> +#include <crypto/ablk_helper.h> +#include <asm/simd.h> + +int ablk_set_key(struct crypto_ablkcipher *tfm, const u8 *key, + unsigned int key_len) +{ + struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm); + struct crypto_ablkcipher *child = &ctx->cryptd_tfm->base; + int err; + + crypto_ablkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_ablkcipher_set_flags(child, crypto_ablkcipher_get_flags(tfm) + & CRYPTO_TFM_REQ_MASK); + err = crypto_ablkcipher_setkey(child, key, key_len); + crypto_ablkcipher_set_flags(tfm, crypto_ablkcipher_get_flags(child) + & CRYPTO_TFM_RES_MASK); + return err; +} +EXPORT_SYMBOL_GPL(ablk_set_key); + +int __ablk_encrypt(struct ablkcipher_request *req) +{ + struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req); + struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm); + struct blkcipher_desc desc; + + desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm); + desc.info = req->info; + desc.flags = 0; + + return crypto_blkcipher_crt(desc.tfm)->encrypt( + &desc, req->dst, req->src, req->nbytes); +} +EXPORT_SYMBOL_GPL(__ablk_encrypt); + +int ablk_encrypt(struct ablkcipher_request *req) +{ + struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req); + struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm); + + if (!may_use_simd()) { + struct ablkcipher_request *cryptd_req = + ablkcipher_request_ctx(req); + + *cryptd_req = *req; + ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base); + + return crypto_ablkcipher_encrypt(cryptd_req); + } else { + return __ablk_encrypt(req); + } +} +EXPORT_SYMBOL_GPL(ablk_encrypt); + +int ablk_decrypt(struct ablkcipher_request *req) +{ + struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req); + struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm); + + if (!may_use_simd()) { + struct ablkcipher_request *cryptd_req = + ablkcipher_request_ctx(req); + + *cryptd_req = *req; + ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base); + + return crypto_ablkcipher_decrypt(cryptd_req); + } else { + struct blkcipher_desc desc; + + desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm); + desc.info = req->info; + desc.flags = 0; + + return crypto_blkcipher_crt(desc.tfm)->decrypt( + &desc, req->dst, req->src, req->nbytes); + } +} +EXPORT_SYMBOL_GPL(ablk_decrypt); + +void ablk_exit(struct crypto_tfm *tfm) +{ + struct async_helper_ctx *ctx = crypto_tfm_ctx(tfm); + + cryptd_free_ablkcipher(ctx->cryptd_tfm); +} +EXPORT_SYMBOL_GPL(ablk_exit); + +int ablk_init_common(struct crypto_tfm *tfm, const char *drv_name) +{ + struct async_helper_ctx *ctx = crypto_tfm_ctx(tfm); + struct cryptd_ablkcipher *cryptd_tfm; + + cryptd_tfm = cryptd_alloc_ablkcipher(drv_name, 0, 0); + if (IS_ERR(cryptd_tfm)) + return PTR_ERR(cryptd_tfm); + + ctx->cryptd_tfm = cryptd_tfm; + tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request) + + crypto_ablkcipher_reqsize(&cryptd_tfm->base); + + return 0; +} +EXPORT_SYMBOL_GPL(ablk_init_common); + +int ablk_init(struct crypto_tfm *tfm) +{ + char drv_name[CRYPTO_MAX_ALG_NAME]; + + snprintf(drv_name, sizeof(drv_name), "__driver-%s", + crypto_tfm_alg_driver_name(tfm)); + + return ablk_init_common(tfm, drv_name); +} +EXPORT_SYMBOL_GPL(ablk_init); + +MODULE_LICENSE("GPL"); diff --git a/crypto/ablkcipher.c b/crypto/ablkcipher.c index 7d4a8d28277e..40886c489903 100644 --- a/crypto/ablkcipher.c +++ b/crypto/ablkcipher.c @@ -16,9 +16,7 @@ #include <crypto/internal/skcipher.h> #include <linux/cpumask.h> #include <linux/err.h> -#include <linux/init.h> #include <linux/kernel.h> -#include <linux/module.h> #include <linux/rtnetlink.h> #include <linux/sched.h> #include <linux/slab.h> @@ -30,8 +28,6 @@ #include "internal.h" -static const char *skcipher_default_geniv __read_mostly; - struct ablkcipher_buffer { struct list_head entry; struct scatter_walk dst; @@ -527,8 +523,7 @@ const char *crypto_default_geniv(const struct crypto_alg *alg) alg->cra_blocksize) return "chainiv"; - return alg->cra_flags & CRYPTO_ALG_ASYNC ? - "eseqiv" : skcipher_default_geniv; + return "eseqiv"; } static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask) @@ -709,17 +704,3 @@ err: return ERR_PTR(err); } EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher); - -static int __init skcipher_module_init(void) -{ - skcipher_default_geniv = num_possible_cpus() > 1 ? - "eseqiv" : "chainiv"; - return 0; -} - -static void skcipher_module_exit(void) -{ -} - -module_init(skcipher_module_init); -module_exit(skcipher_module_exit); diff --git a/crypto/ansi_cprng.c b/crypto/ansi_cprng.c index c0bb3778f1ae..666f1962a160 100644 --- a/crypto/ansi_cprng.c +++ b/crypto/ansi_cprng.c @@ -230,11 +230,11 @@ remainder: */ if (byte_count < DEFAULT_BLK_SZ) { empty_rbuf: - for (; ctx->rand_data_valid < DEFAULT_BLK_SZ; - ctx->rand_data_valid++) { + while (ctx->rand_data_valid < DEFAULT_BLK_SZ) { *ptr = ctx->rand_data[ctx->rand_data_valid]; ptr++; byte_count--; + ctx->rand_data_valid++; if (byte_count == 0) goto done; } diff --git a/crypto/asymmetric_keys/rsa.c b/crypto/asymmetric_keys/rsa.c index 90a17f59ba28..459cf97a75e2 100644 --- a/crypto/asymmetric_keys/rsa.c +++ b/crypto/asymmetric_keys/rsa.c @@ -13,6 +13,7 @@ #include <linux/module.h> #include <linux/kernel.h> #include <linux/slab.h> +#include <crypto/algapi.h> #include "public_key.h" MODULE_LICENSE("GPL"); @@ -189,12 +190,12 @@ static int RSA_verify(const u8 *H, const u8 *EM, size_t k, size_t hash_size, } } - if (memcmp(asn1_template, EM + T_offset, asn1_size) != 0) { + if (crypto_memneq(asn1_template, EM + T_offset, asn1_size) != 0) { kleave(" = -EBADMSG [EM[T] ASN.1 mismatch]"); return -EBADMSG; } - if (memcmp(H, EM + T_offset + asn1_size, hash_size) != 0) { + if (crypto_memneq(H, EM + T_offset + asn1_size, hash_size) != 0) { kleave(" = -EKEYREJECTED [EM[T] hash mismatch]"); return -EKEYREJECTED; } diff --git a/crypto/authenc.c b/crypto/authenc.c index ffce19de05cf..1875e7026e8f 100644 --- a/crypto/authenc.c +++ b/crypto/authenc.c @@ -52,40 +52,52 @@ static void authenc_request_complete(struct aead_request *req, int err) aead_request_complete(req, err); } -static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key, - unsigned int keylen) +int crypto_authenc_extractkeys(struct crypto_authenc_keys *keys, const u8 *key, + unsigned int keylen) { - unsigned int authkeylen; - unsigned int enckeylen; - struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); - struct crypto_ahash *auth = ctx->auth; - struct crypto_ablkcipher *enc = ctx->enc; - struct rtattr *rta = (void *)key; + struct rtattr *rta = (struct rtattr *)key; struct crypto_authenc_key_param *param; - int err = -EINVAL; if (!RTA_OK(rta, keylen)) - goto badkey; + return -EINVAL; if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM) - goto badkey; + return -EINVAL; if (RTA_PAYLOAD(rta) < sizeof(*param)) - goto badkey; + return -EINVAL; param = RTA_DATA(rta); - enckeylen = be32_to_cpu(param->enckeylen); + keys->enckeylen = be32_to_cpu(param->enckeylen); key += RTA_ALIGN(rta->rta_len); keylen -= RTA_ALIGN(rta->rta_len); - if (keylen < enckeylen) - goto badkey; + if (keylen < keys->enckeylen) + return -EINVAL; - authkeylen = keylen - enckeylen; + keys->authkeylen = keylen - keys->enckeylen; + keys->authkey = key; + keys->enckey = key + keys->authkeylen; + + return 0; +} +EXPORT_SYMBOL_GPL(crypto_authenc_extractkeys); + +static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key, + unsigned int keylen) +{ + struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); + struct crypto_ahash *auth = ctx->auth; + struct crypto_ablkcipher *enc = ctx->enc; + struct crypto_authenc_keys keys; + int err = -EINVAL; + + if (crypto_authenc_extractkeys(&keys, key, keylen) != 0) + goto badkey; crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK); crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc) & CRYPTO_TFM_REQ_MASK); - err = crypto_ahash_setkey(auth, key, authkeylen); + err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen); crypto_aead_set_flags(authenc, crypto_ahash_get_flags(auth) & CRYPTO_TFM_RES_MASK); @@ -95,7 +107,7 @@ static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key, crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK); crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) & CRYPTO_TFM_REQ_MASK); - err = crypto_ablkcipher_setkey(enc, key + authkeylen, enckeylen); + err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen); crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) & CRYPTO_TFM_RES_MASK); @@ -188,7 +200,7 @@ static void authenc_verify_ahash_update_done(struct crypto_async_request *areq, scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen, authsize, 0); - err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0; + err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0; if (err) goto out; @@ -227,7 +239,7 @@ static void authenc_verify_ahash_done(struct crypto_async_request *areq, scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen, authsize, 0); - err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0; + err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0; if (err) goto out; @@ -462,7 +474,7 @@ static int crypto_authenc_verify(struct aead_request *req, ihash = ohash + authsize; scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen, authsize, 0); - return memcmp(ihash, ohash, authsize) ? -EBADMSG : 0; + return crypto_memneq(ihash, ohash, authsize) ? -EBADMSG : 0; } static int crypto_authenc_iverify(struct aead_request *req, u8 *iv, diff --git a/crypto/authencesn.c b/crypto/authencesn.c index ab53762fc309..4be0dd4373a9 100644 --- a/crypto/authencesn.c +++ b/crypto/authencesn.c @@ -59,37 +59,19 @@ static void authenc_esn_request_complete(struct aead_request *req, int err) static int crypto_authenc_esn_setkey(struct crypto_aead *authenc_esn, const u8 *key, unsigned int keylen) { - unsigned int authkeylen; - unsigned int enckeylen; struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn); struct crypto_ahash *auth = ctx->auth; struct crypto_ablkcipher *enc = ctx->enc; - struct rtattr *rta = (void *)key; - struct crypto_authenc_key_param *param; + struct crypto_authenc_keys keys; int err = -EINVAL; - if (!RTA_OK(rta, keylen)) + if (crypto_authenc_extractkeys(&keys, key, keylen) != 0) goto badkey; - if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM) - goto badkey; - if (RTA_PAYLOAD(rta) < sizeof(*param)) - goto badkey; - - param = RTA_DATA(rta); - enckeylen = be32_to_cpu(param->enckeylen); - - key += RTA_ALIGN(rta->rta_len); - keylen -= RTA_ALIGN(rta->rta_len); - - if (keylen < enckeylen) - goto badkey; - - authkeylen = keylen - enckeylen; crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK); crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc_esn) & CRYPTO_TFM_REQ_MASK); - err = crypto_ahash_setkey(auth, key, authkeylen); + err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen); crypto_aead_set_flags(authenc_esn, crypto_ahash_get_flags(auth) & CRYPTO_TFM_RES_MASK); @@ -99,7 +81,7 @@ static int crypto_authenc_esn_setkey(struct crypto_aead *authenc_esn, const u8 * crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK); crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc_esn) & CRYPTO_TFM_REQ_MASK); - err = crypto_ablkcipher_setkey(enc, key + authkeylen, enckeylen); + err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen); crypto_aead_set_flags(authenc_esn, crypto_ablkcipher_get_flags(enc) & CRYPTO_TFM_RES_MASK); @@ -247,7 +229,7 @@ static void authenc_esn_verify_ahash_update_done(struct crypto_async_request *ar scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen, authsize, 0); - err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0; + err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0; if (err) goto out; @@ -296,7 +278,7 @@ static void authenc_esn_verify_ahash_update_done2(struct crypto_async_request *a scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen, authsize, 0); - err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0; + err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0; if (err) goto out; @@ -336,7 +318,7 @@ static void authenc_esn_verify_ahash_done(struct crypto_async_request *areq, scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen, authsize, 0); - err = memcmp(ihash, ahreq->result, authsize) ? -EBADMSG : 0; + err = crypto_memneq(ihash, ahreq->result, authsize) ? -EBADMSG : 0; if (err) goto out; @@ -568,7 +550,7 @@ static int crypto_authenc_esn_verify(struct aead_request *req) ihash = ohash + authsize; scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen, authsize, 0); - return memcmp(ihash, ohash, authsize) ? -EBADMSG : 0; + return crypto_memneq(ihash, ohash, authsize) ? -EBADMSG : 0; } static int crypto_authenc_esn_iverify(struct aead_request *req, u8 *iv, diff --git a/crypto/ccm.c b/crypto/ccm.c index 499c91717d93..3e05499d183a 100644 --- a/crypto/ccm.c +++ b/crypto/ccm.c @@ -363,7 +363,7 @@ static void crypto_ccm_decrypt_done(struct crypto_async_request *areq, if (!err) { err = crypto_ccm_auth(req, req->dst, cryptlen); - if (!err && memcmp(pctx->auth_tag, pctx->odata, authsize)) + if (!err && crypto_memneq(pctx->auth_tag, pctx->odata, authsize)) err = -EBADMSG; } aead_request_complete(req, err); @@ -422,7 +422,7 @@ static int crypto_ccm_decrypt(struct aead_request *req) return err; /* verify */ - if (memcmp(authtag, odata, authsize)) + if (crypto_memneq(authtag, odata, authsize)) return -EBADMSG; return err; diff --git a/crypto/gcm.c b/crypto/gcm.c index 43e1fb05ea54..b4f017939004 100644 --- a/crypto/gcm.c +++ b/crypto/gcm.c @@ -582,7 +582,7 @@ static int crypto_gcm_verify(struct aead_request *req, crypto_xor(auth_tag, iauth_tag, 16); scatterwalk_map_and_copy(iauth_tag, req->src, cryptlen, authsize, 0); - return memcmp(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0; + return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0; } static void gcm_decrypt_done(struct crypto_async_request *areq, int err) diff --git a/crypto/memneq.c b/crypto/memneq.c new file mode 100644 index 000000000000..cd0162221c14 --- /dev/null +++ b/crypto/memneq.c @@ -0,0 +1,138 @@ +/* + * Constant-time equality testing of memory regions. + * + * Authors: + * + * James Yonan <james@openvpn.net> + * Daniel Borkmann <dborkman@redhat.com> + * + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * The full GNU General Public License is included in this distribution + * in the file called LICENSE.GPL. + * + * BSD LICENSE + * + * Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of OpenVPN Technologies nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <crypto/algapi.h> + +#ifndef __HAVE_ARCH_CRYPTO_MEMNEQ + +/* Generic path for arbitrary size */ +static inline unsigned long +__crypto_memneq_generic(const void *a, const void *b, size_t size) +{ + unsigned long neq = 0; + +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) + while (size >= sizeof(unsigned long)) { + neq |= *(unsigned long *)a ^ *(unsigned long *)b; + a += sizeof(unsigned long); + b += sizeof(unsigned long); + size -= sizeof(unsigned long); + } +#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */ + while (size > 0) { + neq |= *(unsigned char *)a ^ *(unsigned char *)b; + a += 1; + b += 1; + size -= 1; + } + return neq; +} + +/* Loop-free fast-path for frequently used 16-byte size */ +static inline unsigned long __crypto_memneq_16(const void *a, const void *b) +{ +#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS + if (sizeof(unsigned long) == 8) + return ((*(unsigned long *)(a) ^ *(unsigned long *)(b)) + | (*(unsigned long *)(a+8) ^ *(unsigned long *)(b+8))); + else if (sizeof(unsigned int) == 4) + return ((*(unsigned int *)(a) ^ *(unsigned int *)(b)) + | (*(unsigned int *)(a+4) ^ *(unsigned int *)(b+4)) + | (*(unsigned int *)(a+8) ^ *(unsigned int *)(b+8)) + | (*(unsigned int *)(a+12) ^ *(unsigned int *)(b+12))); + else +#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */ + return ((*(unsigned char *)(a) ^ *(unsigned char *)(b)) + | (*(unsigned char *)(a+1) ^ *(unsigned char *)(b+1)) + | (*(unsigned char *)(a+2) ^ *(unsigned char *)(b+2)) + | (*(unsigned char *)(a+3) ^ *(unsigned char *)(b+3)) + | (*(unsigned char *)(a+4) ^ *(unsigned char *)(b+4)) + | (*(unsigned char *)(a+5) ^ *(unsigned char *)(b+5)) + | (*(unsigned char *)(a+6) ^ *(unsigned char *)(b+6)) + | (*(unsigned char *)(a+7) ^ *(unsigned char *)(b+7)) + | (*(unsigned char *)(a+8) ^ *(unsigned char *)(b+8)) + | (*(unsigned char *)(a+9) ^ *(unsigned char *)(b+9)) + | (*(unsigned char *)(a+10) ^ *(unsigned char *)(b+10)) + | (*(unsigned char *)(a+11) ^ *(unsigned char *)(b+11)) + | (*(unsigned char *)(a+12) ^ *(unsigned char *)(b+12)) + | (*(unsigned char *)(a+13) ^ *(unsigned char *)(b+13)) + | (*(unsigned char *)(a+14) ^ *(unsigned char *)(b+14)) + | (*(unsigned char *)(a+15) ^ *(unsigned char *)(b+15))); +} + +/* Compare two areas of memory without leaking timing information, + * and with special optimizations for common sizes. Users should + * not call this function directly, but should instead use + * crypto_memneq defined in crypto/algapi.h. + */ +noinline unsigned long __crypto_memneq(const void *a, const void *b, + size_t size) +{ + switch (size) { + case 16: + return __crypto_memneq_16(a, b); + default: + return __crypto_memneq_generic(a, b, size); + } +} +EXPORT_SYMBOL(__crypto_memneq); + +#endif /* __HAVE_ARCH_CRYPTO_MEMNEQ */ |