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author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-07-24 12:28:15 +0200 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2017-08-04 03:27:22 +0200 |
commit | ec808bbef0b15ad103771222d419245617378f32 (patch) | |
tree | d124df8125277a21a7449274f606295eca344ba9 /arch/arm64/crypto/aes-neonbs-glue.c | |
parent | crypto: arm64/chacha20 - take may_use_simd() into account (diff) | |
download | linux-ec808bbef0b15ad103771222d419245617378f32.tar.xz linux-ec808bbef0b15ad103771222d419245617378f32.zip |
crypto: arm64/aes-bs - implement non-SIMD fallback for AES-CTR
Of the various chaining modes implemented by the bit sliced AES driver,
only CTR is exposed as a synchronous cipher, and requires a fallback in
order to remain usable once we update the kernel mode NEON handling logic
to disallow nested use. So wire up the existing CTR fallback C code.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to '')
-rw-r--r-- | arch/arm64/crypto/aes-neonbs-glue.c | 48 |
1 files changed, 43 insertions, 5 deletions
diff --git a/arch/arm64/crypto/aes-neonbs-glue.c b/arch/arm64/crypto/aes-neonbs-glue.c index 9001aec16007..c55d68ccb89f 100644 --- a/arch/arm64/crypto/aes-neonbs-glue.c +++ b/arch/arm64/crypto/aes-neonbs-glue.c @@ -1,7 +1,7 @@ /* * Bit sliced AES using NEON instructions * - * Copyright (C) 2016 Linaro Ltd <ard.biesheuvel@linaro.org> + * Copyright (C) 2016 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -9,12 +9,15 @@ */ #include <asm/neon.h> +#include <asm/simd.h> #include <crypto/aes.h> #include <crypto/internal/simd.h> #include <crypto/internal/skcipher.h> #include <crypto/xts.h> #include <linux/module.h> +#include "aes-ctr-fallback.h" + MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); MODULE_LICENSE("GPL v2"); @@ -58,6 +61,11 @@ struct aesbs_cbc_ctx { u32 enc[AES_MAX_KEYLENGTH_U32]; }; +struct aesbs_ctr_ctx { + struct aesbs_ctx key; /* must be first member */ + struct crypto_aes_ctx fallback; +}; + struct aesbs_xts_ctx { struct aesbs_ctx key; u32 twkey[AES_MAX_KEYLENGTH_U32]; @@ -196,6 +204,25 @@ static int cbc_decrypt(struct skcipher_request *req) return err; } +static int aesbs_ctr_setkey_sync(struct crypto_skcipher *tfm, const u8 *in_key, + unsigned int key_len) +{ + struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm); + int err; + + err = crypto_aes_expand_key(&ctx->fallback, in_key, key_len); + if (err) + return err; + + ctx->key.rounds = 6 + key_len / 4; + + kernel_neon_begin(); + aesbs_convert_key(ctx->key.rk, ctx->fallback.key_enc, ctx->key.rounds); + kernel_neon_end(); + + return 0; +} + static int ctr_encrypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); @@ -259,6 +286,17 @@ static int aesbs_xts_setkey(struct crypto_skcipher *tfm, const u8 *in_key, return aesbs_setkey(tfm, in_key, key_len); } +static int ctr_encrypt_sync(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm); + + if (!may_use_simd()) + return aes_ctr_encrypt_fallback(&ctx->fallback, req); + + return ctr_encrypt(req); +} + static int __xts_crypt(struct skcipher_request *req, void (*fn)(u8 out[], u8 const in[], u8 const rk[], int rounds, int blocks, u8 iv[])) @@ -355,7 +393,7 @@ static struct skcipher_alg aes_algs[] = { { .base.cra_driver_name = "ctr-aes-neonbs", .base.cra_priority = 250 - 1, .base.cra_blocksize = 1, - .base.cra_ctxsize = sizeof(struct aesbs_ctx), + .base.cra_ctxsize = sizeof(struct aesbs_ctr_ctx), .base.cra_module = THIS_MODULE, .min_keysize = AES_MIN_KEY_SIZE, @@ -363,9 +401,9 @@ static struct skcipher_alg aes_algs[] = { { .chunksize = AES_BLOCK_SIZE, .walksize = 8 * AES_BLOCK_SIZE, .ivsize = AES_BLOCK_SIZE, - .setkey = aesbs_setkey, - .encrypt = ctr_encrypt, - .decrypt = ctr_encrypt, + .setkey = aesbs_ctr_setkey_sync, + .encrypt = ctr_encrypt_sync, + .decrypt = ctr_encrypt_sync, }, { .base.cra_name = "__xts(aes)", .base.cra_driver_name = "__xts-aes-neonbs", |