alistair23-linux/arch/arm64/crypto/aes-glue.c
Ard Biesheuvel 49788fe2a1 arm64/crypto: AES-ECB/CBC/CTR/XTS using ARMv8 NEON and Crypto Extensions
This adds ARMv8 implementations of AES in ECB, CBC, CTR and XTS modes,
both for ARMv8 with Crypto Extensions and for plain ARMv8 NEON.

The Crypto Extensions version can only run on ARMv8 implementations that
have support for these optional extensions.

The plain NEON version is a table based yet time invariant implementation.
All S-box substitutions are performed in parallel, leveraging the wide range
of ARMv8's tbl/tbx instructions, and the huge NEON register file, which can
comfortably hold the entire S-box and still have room to spare for doing the
actual computations.

The key expansion routines were borrowed from aes_generic.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-05-14 10:04:16 -07:00

447 lines
13 KiB
C

/*
* linux/arch/arm64/crypto/aes-glue.c - wrapper code for ARMv8 AES
*
* Copyright (C) 2013 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 <asm/hwcap.h>
#include <crypto/aes.h>
#include <crypto/ablk_helper.h>
#include <crypto/algapi.h>
#include <linux/module.h>
#include <linux/cpufeature.h>
#ifdef USE_V8_CRYPTO_EXTENSIONS
#define MODE "ce"
#define PRIO 300
#define aes_ecb_encrypt ce_aes_ecb_encrypt
#define aes_ecb_decrypt ce_aes_ecb_decrypt
#define aes_cbc_encrypt ce_aes_cbc_encrypt
#define aes_cbc_decrypt ce_aes_cbc_decrypt
#define aes_ctr_encrypt ce_aes_ctr_encrypt
#define aes_xts_encrypt ce_aes_xts_encrypt
#define aes_xts_decrypt ce_aes_xts_decrypt
MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS using ARMv8 Crypto Extensions");
#else
#define MODE "neon"
#define PRIO 200
#define aes_ecb_encrypt neon_aes_ecb_encrypt
#define aes_ecb_decrypt neon_aes_ecb_decrypt
#define aes_cbc_encrypt neon_aes_cbc_encrypt
#define aes_cbc_decrypt neon_aes_cbc_decrypt
#define aes_ctr_encrypt neon_aes_ctr_encrypt
#define aes_xts_encrypt neon_aes_xts_encrypt
#define aes_xts_decrypt neon_aes_xts_decrypt
MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS using ARMv8 NEON");
MODULE_ALIAS("ecb(aes)");
MODULE_ALIAS("cbc(aes)");
MODULE_ALIAS("ctr(aes)");
MODULE_ALIAS("xts(aes)");
#endif
MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
MODULE_LICENSE("GPL v2");
/* defined in aes-modes.S */
asmlinkage void aes_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks, int first);
asmlinkage void aes_ecb_decrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks, int first);
asmlinkage void aes_cbc_encrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks, u8 iv[], int first);
asmlinkage void aes_cbc_decrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks, u8 iv[], int first);
asmlinkage void aes_ctr_encrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks, u8 ctr[], int first);
asmlinkage void aes_xts_encrypt(u8 out[], u8 const in[], u8 const rk1[],
int rounds, int blocks, u8 const rk2[], u8 iv[],
int first);
asmlinkage void aes_xts_decrypt(u8 out[], u8 const in[], u8 const rk1[],
int rounds, int blocks, u8 const rk2[], u8 iv[],
int first);
struct crypto_aes_xts_ctx {
struct crypto_aes_ctx key1;
struct crypto_aes_ctx __aligned(8) key2;
};
static int xts_set_key(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct crypto_aes_xts_ctx *ctx = crypto_tfm_ctx(tfm);
int ret;
ret = crypto_aes_expand_key(&ctx->key1, in_key, key_len / 2);
if (!ret)
ret = crypto_aes_expand_key(&ctx->key2, &in_key[key_len / 2],
key_len / 2);
if (!ret)
return 0;
tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}
static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
int err, first, rounds = 6 + ctx->key_length / 4;
struct blkcipher_walk walk;
unsigned int blocks;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
aes_ecb_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_enc, rounds, blocks, first);
err = blkcipher_walk_done(desc, &walk, 0);
}
kernel_neon_end();
return err;
}
static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
int err, first, rounds = 6 + ctx->key_length / 4;
struct blkcipher_walk walk;
unsigned int blocks;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
aes_ecb_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_dec, rounds, blocks, first);
err = blkcipher_walk_done(desc, &walk, 0);
}
kernel_neon_end();
return err;
}
static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
int err, first, rounds = 6 + ctx->key_length / 4;
struct blkcipher_walk walk;
unsigned int blocks;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_enc, rounds, blocks, walk.iv,
first);
err = blkcipher_walk_done(desc, &walk, 0);
}
kernel_neon_end();
return err;
}
static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
int err, first, rounds = 6 + ctx->key_length / 4;
struct blkcipher_walk walk;
unsigned int blocks;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_dec, rounds, blocks, walk.iv,
first);
err = blkcipher_walk_done(desc, &walk, 0);
}
kernel_neon_end();
return err;
}
static int ctr_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
int err, first, rounds = 6 + ctx->key_length / 4;
struct blkcipher_walk walk;
int blocks;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
first = 1;
kernel_neon_begin();
while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
aes_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_enc, rounds, blocks, walk.iv,
first);
first = 0;
nbytes -= blocks * AES_BLOCK_SIZE;
if (nbytes && nbytes == walk.nbytes % AES_BLOCK_SIZE)
break;
err = blkcipher_walk_done(desc, &walk,
walk.nbytes % AES_BLOCK_SIZE);
}
if (nbytes) {
u8 *tdst = walk.dst.virt.addr + blocks * AES_BLOCK_SIZE;
u8 *tsrc = walk.src.virt.addr + blocks * AES_BLOCK_SIZE;
u8 __aligned(8) tail[AES_BLOCK_SIZE];
/*
* Minimum alignment is 8 bytes, so if nbytes is <= 8, we need
* to tell aes_ctr_encrypt() to only read half a block.
*/
blocks = (nbytes <= 8) ? -1 : 1;
aes_ctr_encrypt(tail, tsrc, (u8 *)ctx->key_enc, rounds,
blocks, walk.iv, first);
memcpy(tdst, tail, nbytes);
err = blkcipher_walk_done(desc, &walk, 0);
}
kernel_neon_end();
return err;
}
static int xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct crypto_aes_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
int err, first, rounds = 6 + ctx->key1.key_length / 4;
struct blkcipher_walk walk;
unsigned int blocks;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
aes_xts_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key1.key_enc, rounds, blocks,
(u8 *)ctx->key2.key_enc, walk.iv, first);
err = blkcipher_walk_done(desc, &walk, 0);
}
kernel_neon_end();
return err;
}
static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct crypto_aes_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
int err, first, rounds = 6 + ctx->key1.key_length / 4;
struct blkcipher_walk walk;
unsigned int blocks;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
aes_xts_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key1.key_dec, rounds, blocks,
(u8 *)ctx->key2.key_enc, walk.iv, first);
err = blkcipher_walk_done(desc, &walk, 0);
}
kernel_neon_end();
return err;
}
static struct crypto_alg aes_algs[] = { {
.cra_name = "__ecb-aes-" MODE,
.cra_driver_name = "__driver-ecb-aes-" MODE,
.cra_priority = 0,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct crypto_aes_ctx),
.cra_alignmask = 7,
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_blkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = crypto_aes_set_key,
.encrypt = ecb_encrypt,
.decrypt = ecb_decrypt,
},
}, {
.cra_name = "__cbc-aes-" MODE,
.cra_driver_name = "__driver-cbc-aes-" MODE,
.cra_priority = 0,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct crypto_aes_ctx),
.cra_alignmask = 7,
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_blkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = crypto_aes_set_key,
.encrypt = cbc_encrypt,
.decrypt = cbc_decrypt,
},
}, {
.cra_name = "__ctr-aes-" MODE,
.cra_driver_name = "__driver-ctr-aes-" MODE,
.cra_priority = 0,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct crypto_aes_ctx),
.cra_alignmask = 7,
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_blkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = crypto_aes_set_key,
.encrypt = ctr_encrypt,
.decrypt = ctr_encrypt,
},
}, {
.cra_name = "__xts-aes-" MODE,
.cra_driver_name = "__driver-xts-aes-" MODE,
.cra_priority = 0,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct crypto_aes_xts_ctx),
.cra_alignmask = 7,
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_blkcipher = {
.min_keysize = 2 * AES_MIN_KEY_SIZE,
.max_keysize = 2 * AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = xts_set_key,
.encrypt = xts_encrypt,
.decrypt = xts_decrypt,
},
}, {
.cra_name = "ecb(aes)",
.cra_driver_name = "ecb-aes-" MODE,
.cra_priority = PRIO,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct async_helper_ctx),
.cra_alignmask = 7,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = ablk_init,
.cra_exit = ablk_exit,
.cra_ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = ablk_set_key,
.encrypt = ablk_encrypt,
.decrypt = ablk_decrypt,
}
}, {
.cra_name = "cbc(aes)",
.cra_driver_name = "cbc-aes-" MODE,
.cra_priority = PRIO,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct async_helper_ctx),
.cra_alignmask = 7,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = ablk_init,
.cra_exit = ablk_exit,
.cra_ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = ablk_set_key,
.encrypt = ablk_encrypt,
.decrypt = ablk_decrypt,
}
}, {
.cra_name = "ctr(aes)",
.cra_driver_name = "ctr-aes-" MODE,
.cra_priority = PRIO,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct async_helper_ctx),
.cra_alignmask = 7,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = ablk_init,
.cra_exit = ablk_exit,
.cra_ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = ablk_set_key,
.encrypt = ablk_encrypt,
.decrypt = ablk_decrypt,
}
}, {
.cra_name = "xts(aes)",
.cra_driver_name = "xts-aes-" MODE,
.cra_priority = PRIO,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct async_helper_ctx),
.cra_alignmask = 7,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = ablk_init,
.cra_exit = ablk_exit,
.cra_ablkcipher = {
.min_keysize = 2 * AES_MIN_KEY_SIZE,
.max_keysize = 2 * AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = ablk_set_key,
.encrypt = ablk_encrypt,
.decrypt = ablk_decrypt,
}
} };
static int __init aes_init(void)
{
return crypto_register_algs(aes_algs, ARRAY_SIZE(aes_algs));
}
static void __exit aes_exit(void)
{
crypto_unregister_algs(aes_algs, ARRAY_SIZE(aes_algs));
}
#ifdef USE_V8_CRYPTO_EXTENSIONS
module_cpu_feature_match(AES, aes_init);
#else
module_init(aes_init);
#endif
module_exit(aes_exit);