- 根目录:
- arch
- arm
- crypto
- aes-ce-glue.c
/*
* aes-ce-glue.c - wrapper code for ARMv8 AES
*
* Copyright (C) 2015 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/hwcap.h>
#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>
MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS using ARMv8 Crypto Extensions");
MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
MODULE_LICENSE("GPL v2");
/* defined in aes-ce-core.S */
asmlinkage u32 ce_aes_sub(u32 input);
asmlinkage void ce_aes_invert(void *dst, void *src);
asmlinkage void ce_aes_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks);
asmlinkage void ce_aes_ecb_decrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks);
asmlinkage void ce_aes_cbc_encrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks, u8 iv[]);
asmlinkage void ce_aes_cbc_decrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks, u8 iv[]);
asmlinkage void ce_aes_ctr_encrypt(u8 out[], u8 const in[], u8 const rk[],
int rounds, int blocks, u8 ctr[]);
asmlinkage void ce_aes_xts_encrypt(u8 out[], u8 const in[], u8 const rk1[],
int rounds, int blocks, u8 iv[],
u8 const rk2[], int first);
asmlinkage void ce_aes_xts_decrypt(u8 out[], u8 const in[], u8 const rk1[],
int rounds, int blocks, u8 iv[],
u8 const rk2[], int first);
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 int ce_aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
unsigned int key_len)
{
/*
* The AES key schedule round constants
*/
static u8 const rcon[] = {
0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36,
};
u32 kwords = key_len / sizeof(u32);
struct aes_block *key_enc, *key_dec;
int i, j;
if (key_len != AES_KEYSIZE_128 &&
key_len != AES_KEYSIZE_192 &&
key_len != AES_KEYSIZE_256)
return -EINVAL;
memcpy(ctx->key_enc, in_key, key_len);
ctx->key_length = key_len;
kernel_neon_begin();
for (i = 0; i < sizeof(rcon); i++) {
u32 *rki = ctx->key_enc + (i * kwords);
u32 *rko = rki + kwords;
rko[0] = ror32(ce_aes_sub(rki[kwords - 1]), 8);
rko[0] = rko[0] ^ rki[0] ^ rcon[i];
rko[1] = rko[0] ^ rki[1];
rko[2] = rko[1] ^ rki[2];
rko[3] = rko[2] ^ rki[3];
if (key_len == AES_KEYSIZE_192) {
if (i >= 7)
break;
rko[4] = rko[3] ^ rki[4];
rko[5] = rko[4] ^ rki[5];
} else if (key_len == AES_KEYSIZE_256) {
if (i >= 6)
break;
rko[4] = ce_aes_sub(rko[3]) ^ rki[4];
rko[5] = rko[4] ^ rki[5];
rko[6] = rko[5] ^ rki[6];
rko[7] = rko[6] ^ rki[7];
}
}
/*
* Generate the decryption keys for the Equivalent Inverse Cipher.
* This involves reversing the order of the round keys, and applying
* the Inverse Mix Columns transformation on all but the first and
* the last one.
*/
key_enc = (struct aes_block *)ctx->key_enc;
key_dec = (struct aes_block *)ctx->key_dec;
j = num_rounds(ctx);
key_dec[0] = key_enc[j];
for (i = 1, j--; j > 0; i++, j--)
ce_aes_invert(key_dec + i, key_enc + j);
key_dec[i] = key_enc[0];
kernel_neon_end();
return 0;
}
static int ce_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
int ret;
ret = ce_aes_expandkey(ctx, in_key, key_len);
if (!ret)
return 0;
tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}
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 = ce_aes_expandkey(&ctx->key1, in_key, key_len / 2);
if (!ret)
ret = ce_aes_expandkey(&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);
struct blkcipher_walk walk;
unsigned int blocks;
int err;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
ce_aes_ecb_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_enc, num_rounds(ctx), blocks);
err = blkcipher_walk_done(desc, &walk,
walk.nbytes % AES_BLOCK_SIZE);
}
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);
struct blkcipher_walk walk;
unsigned int blocks;
int err;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
ce_aes_ecb_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_dec, num_rounds(ctx), blocks);
err = blkcipher_walk_done(desc, &walk,
walk.nbytes % AES_BLOCK_SIZE);
}
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);
struct blkcipher_walk walk;
unsigned int blocks;
int err;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
ce_aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_enc, num_rounds(ctx), blocks,
walk.iv);
err = blkcipher_walk_done(desc, &walk,
walk.nbytes % AES_BLOCK_SIZE);
}
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);
struct blkcipher_walk walk;
unsigned int blocks;
int err;
desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt(desc, &walk);
kernel_neon_begin();
while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
ce_aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_dec, num_rounds(ctx), blocks,
walk.iv);
err = blkcipher_walk_done(desc, &walk,
walk.nbytes % AES_BLOCK_SIZE);
}
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);
struct blkcipher_walk walk;
int err, 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);
kernel_neon_begin();
while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
ce_aes_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key_enc, num_rounds(ctx), blocks,
walk.iv);
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;
ce_aes_ctr_encrypt(tail, tsrc, (u8 *)ctx->key_enc,
num_rounds(ctx), blocks, walk.iv);
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 = num_rounds(&ctx->key1);
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) {
ce_aes_xts_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key1.key_enc, rounds, blocks,
walk.iv, (u8 *)ctx->key2.key_enc, first);
err = blkcipher_walk_done(desc, &walk,
walk.nbytes % AES_BLOCK_SIZE);
}
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 = num_rounds(&ctx->key1);
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) {
ce_aes_xts_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
(u8 *)ctx->key1.key_dec, rounds, blocks,
walk.iv, (u8 *)ctx->key2.key_enc, first);
err = blkcipher_walk_done(desc, &walk,
walk.nbytes % AES_BLOCK_SIZE);
}
kernel_neon_end();
return err;
}
static struct crypto_alg aes_algs[] = { {
.cra_name = "__ecb-aes-ce",
.cra_driver_name = "__driver-ecb-aes-ce",
.cra_priority = 0,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
CRYPTO_ALG_INTERNAL,
.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 = ce_aes_setkey,
.encrypt = ecb_encrypt,
.decrypt = ecb_decrypt,
},
}, {
.cra_name = "__cbc-aes-ce",
.cra_driver_name = "__driver-cbc-aes-ce",
.cra_priority = 0,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
CRYPTO_ALG_INTERNAL,
.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 = ce_aes_setkey,
.encrypt = cbc_encrypt,
.decrypt = cbc_decrypt,
},
}, {
.cra_name = "__ctr-aes-ce",
.cra_driver_name = "__driver-ctr-aes-ce",
.cra_priority = 0,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
CRYPTO_ALG_INTERNAL,
.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 = ce_aes_setkey,
.encrypt = ctr_encrypt,
.decrypt = ctr_encrypt,
},
}, {
.cra_name = "__xts-aes-ce",
.cra_driver_name = "__driver-xts-aes-ce",
.cra_priority = 0,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
CRYPTO_ALG_INTERNAL,
.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-ce",
.cra_priority = 300,
.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-ce",
.cra_priority = 300,
.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-ce",
.cra_priority = 300,
.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-ce",
.cra_priority = 300,
.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)
{
if (!(elf_hwcap2 & HWCAP2_AES))
return -ENODEV;
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));
}
module_init(aes_init);
module_exit(aes_exit);