From mboxrd@z Thu Jan 1 00:00:00 1970 From: ard.biesheuvel@linaro.org (Ard Biesheuvel) Date: Wed, 9 Oct 2013 20:50:33 +0200 Subject: [RFC v2 PATCH 3/4] ARM64: add Crypto Extensions based synchronous core AES cipher In-Reply-To: <1381344634-14917-1-git-send-email-ard.biesheuvel@linaro.org> References: <1381344634-14917-1-git-send-email-ard.biesheuvel@linaro.org> Message-ID: <1381344634-14917-4-git-send-email-ard.biesheuvel@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This implements the core AES cipher using the Crypto Extensions, using only NEON register q0 and q1. Signed-off-by: Ard Biesheuvel --- arch/arm64/crypto/Makefile | 12 +++++ arch/arm64/crypto/aes-sync.c | 106 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 118 insertions(+) create mode 100644 arch/arm64/crypto/Makefile create mode 100644 arch/arm64/crypto/aes-sync.c diff --git a/arch/arm64/crypto/Makefile b/arch/arm64/crypto/Makefile new file mode 100644 index 0000000..7c636e9 --- /dev/null +++ b/arch/arm64/crypto/Makefile @@ -0,0 +1,12 @@ +# +# linux/arch/arm64/crypto/Makefile +# +# Copyright (C) 2013 Linaro Ltd +# +# 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 +# published by the Free Software Foundation. +# + +aesce-sync-y := aes-sync.o +obj-m += aesce-sync.o diff --git a/arch/arm64/crypto/aes-sync.c b/arch/arm64/crypto/aes-sync.c new file mode 100644 index 0000000..d047d49 --- /dev/null +++ b/arch/arm64/crypto/aes-sync.c @@ -0,0 +1,106 @@ +/* + * linux/arch/arm64/crypto/aes-sync.c + * + * Copyright (C) 2013 Linaro Ltd + * + * 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 + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include + +static void aes_cipher_encrypt(struct crypto_tfm *tfm, u8 dst[], u8 const src[]) +{ + struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm); + int rounds = 6 + ctx->key_length / 4; + DEFINE_NEON_STACK_REGS(regs, 2); + + kernel_neon_begin_atomic(regs); + + __asm__(" .arch armv8-a+crypto \n\t" + " ld1 {v0.16b}, [%[in]] \n\t" + " ld1 {v1.16b}, [%[key]], #16 \n\t" + "0: aese v0.16b, v1.16b \n\t" + " subs %[rounds], %[rounds], #1 \n\t" + " ld1 {v1.16b}, [%[key]], #16 \n\t" + " beq 1f \n\t" + " aesmc v0.16b, v0.16b \n\t" + " b 0b \n\t" + "1: eor v0.16b, v0.16b, v1.16b \n\t" + " st1 {v0.16b}, [%[out]] \n\t" + : : + [out] "r"(dst), + [in] "r"(src), + [rounds] "r"(rounds), + [key] "r"(ctx->key_enc)); + + kernel_neon_end_atomic(regs); +} + +static void aes_cipher_decrypt(struct crypto_tfm *tfm, u8 dst[], u8 const src[]) +{ + struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm); + int rounds = 6 + ctx->key_length / 4; + DEFINE_NEON_STACK_REGS(regs, 2); + + kernel_neon_begin_atomic(regs); + + __asm__(" .arch armv8-a+crypto \n\t" + " ld1 {v0.16b}, [%[in]] \n\t" + " ld1 {v1.16b}, [%[key]], #16 \n\t" + "0: aesd v0.16b, v1.16b \n\t" + " ld1 {v1.16b}, [%[key]], #16 \n\t" + " subs %[rounds], %[rounds], #1 \n\t" + " beq 1f \n\t" + " aesimc v0.16b, v0.16b \n\t" + " b 0b \n\t" + "1: eor v0.16b, v0.16b, v1.16b \n\t" + " st1 {v0.16b}, [%[out]] \n\t" + : : + [out] "r"(dst), + [in] "r"(src), + [rounds] "r"(rounds), + [key] "r"(ctx->key_dec)); + + kernel_neon_end_atomic(regs); +} + +static struct crypto_alg aes_alg = { + .cra_name = "aes", + .cra_driver_name = "aes-ce", + .cra_priority = 300, + .cra_flags = CRYPTO_ALG_TYPE_CIPHER, + .cra_blocksize = AES_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct crypto_aes_ctx), + .cra_module = THIS_MODULE, + .cra_cipher = { + .cia_min_keysize = AES_MIN_KEY_SIZE, + .cia_max_keysize = AES_MAX_KEY_SIZE, + .cia_setkey = crypto_aes_set_key, + .cia_encrypt = aes_cipher_encrypt, + .cia_decrypt = aes_cipher_decrypt + } +}; + +static int __init aes_mod_init(void) +{ + if (0) // TODO check for crypto extensions + return -ENODEV; + return crypto_register_alg(&aes_alg); +} + +static void __exit aes_mod_exit(void) +{ + crypto_unregister_alg(&aes_alg); +} + +module_init(aes_mod_init); +module_exit(aes_mod_exit); + +MODULE_DESCRIPTION("Synchronous AES using ARMv8 Crypto Extensions"); +MODULE_AUTHOR("Ard Biesheuvel "); +MODULE_LICENSE("GPL"); -- 1.8.1.2