From 317f2f750d708d684bddd8cb14827ec2efee4b1c Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 5 Feb 2014 18:13:38 +0100 Subject: arm64/crypto: AES using ARMv8 Crypto Extensions This patch adds support for the AES symmetric encryption algorithm for CPUs that have support for the AES part of the ARM v8 Crypto Extensions. Signed-off-by: Ard Biesheuvel Acked-by: Herbert Xu --- arch/arm64/crypto/aes-ce-cipher.c | 155 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 arch/arm64/crypto/aes-ce-cipher.c (limited to 'arch/arm64/crypto/aes-ce-cipher.c') diff --git a/arch/arm64/crypto/aes-ce-cipher.c b/arch/arm64/crypto/aes-ce-cipher.c new file mode 100644 index 000000000000..2075e1acae6b --- /dev/null +++ b/arch/arm64/crypto/aes-ce-cipher.c @@ -0,0 +1,155 @@ +/* + * aes-ce-cipher.c - core AES cipher using ARMv8 Crypto Extensions + * + * Copyright (C) 2013 - 2014 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 +#include + +MODULE_DESCRIPTION("Synchronous AES cipher using ARMv8 Crypto Extensions"); +MODULE_AUTHOR("Ard Biesheuvel "); +MODULE_LICENSE("GPL v2"); + +struct aes_block { + u8 b[AES_BLOCK_SIZE]; +}; + +static int num_rounds(struct crypto_aes_ctx *ctx) +{ + /* + * # of rounds specified by AES: + * 128 bit key 10 rounds + * 192 bit key 12 rounds + * 256 bit key 14 rounds + * => n byte key => 6 + (n/4) rounds + */ + return 6 + ctx->key_length / 4; +} + +static void aes_cipher_encrypt(struct crypto_tfm *tfm, u8 dst[], u8 const src[]) +{ + struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm); + struct aes_block *out = (struct aes_block *)dst; + struct aes_block const *in = (struct aes_block *)src; + void *dummy0; + int dummy1; + + kernel_neon_begin_partial(4); + + __asm__(" ld1 {v0.16b}, %[in] ;" + " ld1 {v1.2d}, [%[key]], #16 ;" + " cmp %w[rounds], #10 ;" + " bmi 0f ;" + " bne 3f ;" + " mov v3.16b, v1.16b ;" + " b 2f ;" + "0: mov v2.16b, v1.16b ;" + " ld1 {v3.2d}, [%[key]], #16 ;" + "1: aese v0.16b, v2.16b ;" + " aesmc v0.16b, v0.16b ;" + "2: ld1 {v1.2d}, [%[key]], #16 ;" + " aese v0.16b, v3.16b ;" + " aesmc v0.16b, v0.16b ;" + "3: ld1 {v2.2d}, [%[key]], #16 ;" + " subs %w[rounds], %w[rounds], #3 ;" + " aese v0.16b, v1.16b ;" + " aesmc v0.16b, v0.16b ;" + " ld1 {v3.2d}, [%[key]], #16 ;" + " bpl 1b ;" + " aese v0.16b, v2.16b ;" + " eor v0.16b, v0.16b, v3.16b ;" + " st1 {v0.16b}, %[out] ;" + + : [out] "=Q"(*out), + [key] "=r"(dummy0), + [rounds] "=r"(dummy1) + : [in] "Q"(*in), + "1"(ctx->key_enc), + "2"(num_rounds(ctx) - 2) + : "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); + struct aes_block *out = (struct aes_block *)dst; + struct aes_block const *in = (struct aes_block *)src; + void *dummy0; + int dummy1; + + kernel_neon_begin_partial(4); + + __asm__(" ld1 {v0.16b}, %[in] ;" + " ld1 {v1.2d}, [%[key]], #16 ;" + " cmp %w[rounds], #10 ;" + " bmi 0f ;" + " bne 3f ;" + " mov v3.16b, v1.16b ;" + " b 2f ;" + "0: mov v2.16b, v1.16b ;" + " ld1 {v3.2d}, [%[key]], #16 ;" + "1: aesd v0.16b, v2.16b ;" + " aesimc v0.16b, v0.16b ;" + "2: ld1 {v1.2d}, [%[key]], #16 ;" + " aesd v0.16b, v3.16b ;" + " aesimc v0.16b, v0.16b ;" + "3: ld1 {v2.2d}, [%[key]], #16 ;" + " subs %w[rounds], %w[rounds], #3 ;" + " aesd v0.16b, v1.16b ;" + " aesimc v0.16b, v0.16b ;" + " ld1 {v3.2d}, [%[key]], #16 ;" + " bpl 1b ;" + " aesd v0.16b, v2.16b ;" + " eor v0.16b, v0.16b, v3.16b ;" + " st1 {v0.16b}, %[out] ;" + + : [out] "=Q"(*out), + [key] "=r"(dummy0), + [rounds] "=r"(dummy1) + : [in] "Q"(*in), + "1"(ctx->key_dec), + "2"(num_rounds(ctx) - 2) + : "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) +{ + return crypto_register_alg(&aes_alg); +} + +static void __exit aes_mod_exit(void) +{ + crypto_unregister_alg(&aes_alg); +} + +module_cpu_feature_match(AES, aes_mod_init); +module_exit(aes_mod_exit); -- cgit v1.2.3