This implements the core AES cipher using the Crypto Extensions, using only NEON registers q0 and q1.
Signed-off-by: Ard Biesheuvel <[email protected]> --- arch/arm64/Makefile | 1 + arch/arm64/crypto/Makefile | 13 +++++ arch/arm64/crypto/aes-ce-cipher.c | 112 ++++++++++++++++++++++++++++++++++++++ crypto/Kconfig | 6 ++ 4 files changed, 132 insertions(+) create mode 100644 arch/arm64/crypto/Makefile create mode 100644 arch/arm64/crypto/aes-ce-cipher.c diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index e0b75464b7f1..a4b3e253557d 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -46,6 +46,7 @@ core-y += arch/arm64/emu/ core-y += arch/arm64/kernel/ arch/arm64/mm/ core-$(CONFIG_KVM) += arch/arm64/kvm/ core-$(CONFIG_XEN) += arch/arm64/xen/ +core-$(CONFIG_CRYPTO) += arch/arm64/crypto/ libs-y := arch/arm64/lib/ $(libs-y) libs-y += $(LIBGCC) diff --git a/arch/arm64/crypto/Makefile b/arch/arm64/crypto/Makefile new file mode 100644 index 000000000000..ac58945c50b3 --- /dev/null +++ b/arch/arm64/crypto/Makefile @@ -0,0 +1,13 @@ +# +# linux/arch/arm64/crypto/Makefile +# +# Copyright (C) 2013 Linaro Ltd <[email protected]> +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License version 2 as +# published by the Free Software Foundation. +# + +obj-$(CONFIG_CRYPTO_AES_ARM64_CE) += aes-ce-cipher.o + +CFLAGS_aes-ce-cipher.o += -march=armv8-a+crypto diff --git a/arch/arm64/crypto/aes-ce-cipher.c b/arch/arm64/crypto/aes-ce-cipher.c new file mode 100644 index 000000000000..dd132c2d69ab --- /dev/null +++ b/arch/arm64/crypto/aes-ce-cipher.c @@ -0,0 +1,112 @@ +/* + * linux/arch/arm64/crypto/aes-sync.c + * + * Copyright (C) 2013 Linaro Ltd <[email protected]> + * + * 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 <asm/hwcap.h> +#include <asm/neon.h> +#include <crypto/aes.h> +#include <linux/crypto.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> + +MODULE_DESCRIPTION("Synchronous AES cipher using ARMv8 Crypto Extensions"); +MODULE_AUTHOR("Ard Biesheuvel <[email protected]>"); +MODULE_LICENSE("GPL"); + +static struct cpu_feature const feat_hwcap_aes[] = { + { CPU_FEATURE_HWCAP(HWCAP_AES) }, + { } +}; +MODULE_DEVICE_TABLE(cpu, feat_hwcap_aes); + +static void aes_cipher_encrypt(struct crypto_tfm *tfm, u8 dst[], u8 const src[]) +{ + struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm); + u32 rounds = 6 + ctx->key_length / 4; + + kernel_neon_begin_partial(2); + + __asm__(" ld1 {v0.16b}, [%[in]] ;" + " ld1 {v1.16b}, [%[key]], #16 ;" + "0: aese v0.16b, v1.16b ;" + " subs %[rounds], %[rounds], #1 ;" + " ld1 {v1.16b}, [%[key]], #16 ;" + " beq 1f ;" + " aesmc v0.16b, v0.16b ;" + " b 0b ;" + "1: eor v0.16b, v0.16b, v1.16b ;" + " st1 {v0.16b}, [%[out]] ;" + : : + [out] "r"(dst), + [in] "r"(src), + [rounds] "r"(rounds), + [key] "r"(ctx->key_enc) + : "cc"); + + kernel_neon_end(); +} + +static void aes_cipher_decrypt(struct crypto_tfm *tfm, u8 dst[], u8 const src[]) +{ + struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm); + u32 rounds = 6 + ctx->key_length / 4; + + kernel_neon_begin_partial(2); + + __asm__(" ld1 {v0.16b}, [%[in]] ;" + " ld1 {v1.16b}, [%[key]], #16 ;" + "0: aesd v0.16b, v1.16b ;" + " ld1 {v1.16b}, [%[key]], #16 ;" + " subs %[rounds], %[rounds], #1 ;" + " beq 1f ;" + " aesimc v0.16b, v0.16b ;" + " b 0b ;" + "1: eor v0.16b, v0.16b, v1.16b ;" + " st1 {v0.16b}, [%[out]] ;" + : : + [out] "r"(dst), + [in] "r"(src), + [rounds] "r"(rounds), + [key] "r"(ctx->key_dec) + : "cc"); + + kernel_neon_end(); +} + +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 (!(elf_hwcap & HWCAP_AES)) + 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); diff --git a/crypto/Kconfig b/crypto/Kconfig index 7bcb70d216e1..f1d98bc346b6 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -791,6 +791,12 @@ config CRYPTO_AES_ARM_BS This implementation does not rely on any lookup tables so it is believed to be invulnerable to cache timing attacks. +config CRYPTO_AES_ARM64_CE + tristate "Synchronous AES cipher using ARMv8 Crypto Extensions" + depends on ARM64 && KERNEL_MODE_NEON + select CRYPTO_ALGAPI + select CRYPTO_AES + config CRYPTO_ANUBIS tristate "Anubis cipher algorithm" select CRYPTO_ALGAPI -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
