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Diffstat (limited to 'arch/arm64/crypto/aes-ce-cipher.c')
| -rw-r--r-- | arch/arm64/crypto/aes-ce-cipher.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/arch/arm64/crypto/aes-ce-cipher.c b/arch/arm64/crypto/aes-ce-cipher.c new file mode 100644 index 00000000000..2075e1acae6 --- /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 <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 + * published by the Free Software Foundation. + */ + +#include <asm/neon.h> +#include <crypto/aes.h> +#include <linux/cpufeature.h> +#include <linux/crypto.h> +#include <linux/module.h> + +MODULE_DESCRIPTION("Synchronous AES cipher using ARMv8 Crypto Extensions"); +MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); +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); |