linux/drivers/crypto/vmx/aes_cbc.c
Eric Biggers 2621a8699e crypto: vmx - convert to skcipher API
Convert the VMX implementations of AES-CBC, AES-CTR, and AES-XTS from
the deprecated "blkcipher" API to the "skcipher" API.

As part of this, I moved the skcipher_request for the fallback algorithm
off the stack and into the request context of the parent algorithm.

I tested this in a PowerPC VM with CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-05-30 15:28:40 +08:00

134 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/**
* AES CBC routines supporting VMX instructions on the Power 8
*
* Copyright (C) 2015 International Business Machines Inc.
*
* Author: Marcelo Henrique Cerri <mhcerri@br.ibm.com>
*/
#include <asm/simd.h>
#include <asm/switch_to.h>
#include <crypto/aes.h>
#include <crypto/internal/simd.h>
#include <crypto/internal/skcipher.h>
#include "aesp8-ppc.h"
struct p8_aes_cbc_ctx {
struct crypto_skcipher *fallback;
struct aes_key enc_key;
struct aes_key dec_key;
};
static int p8_aes_cbc_init(struct crypto_skcipher *tfm)
{
struct p8_aes_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
struct crypto_skcipher *fallback;
fallback = crypto_alloc_skcipher("cbc(aes)", 0,
CRYPTO_ALG_NEED_FALLBACK |
CRYPTO_ALG_ASYNC);
if (IS_ERR(fallback)) {
pr_err("Failed to allocate cbc(aes) fallback: %ld\n",
PTR_ERR(fallback));
return PTR_ERR(fallback);
}
crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
crypto_skcipher_reqsize(fallback));
ctx->fallback = fallback;
return 0;
}
static void p8_aes_cbc_exit(struct crypto_skcipher *tfm)
{
struct p8_aes_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
crypto_free_skcipher(ctx->fallback);
}
static int p8_aes_cbc_setkey(struct crypto_skcipher *tfm, const u8 *key,
unsigned int keylen)
{
struct p8_aes_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
int ret;
preempt_disable();
pagefault_disable();
enable_kernel_vsx();
ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key);
ret |= aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key);
disable_kernel_vsx();
pagefault_enable();
preempt_enable();
ret |= crypto_skcipher_setkey(ctx->fallback, key, keylen);
return ret ? -EINVAL : 0;
}
static int p8_aes_cbc_crypt(struct skcipher_request *req, int enc)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
const struct p8_aes_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
struct skcipher_walk walk;
unsigned int nbytes;
int ret;
if (!crypto_simd_usable()) {
struct skcipher_request *subreq = skcipher_request_ctx(req);
*subreq = *req;
skcipher_request_set_tfm(subreq, ctx->fallback);
return enc ? crypto_skcipher_encrypt(subreq) :
crypto_skcipher_decrypt(subreq);
}
ret = skcipher_walk_virt(&walk, req, false);
while ((nbytes = walk.nbytes) != 0) {
preempt_disable();
pagefault_disable();
enable_kernel_vsx();
aes_p8_cbc_encrypt(walk.src.virt.addr,
walk.dst.virt.addr,
round_down(nbytes, AES_BLOCK_SIZE),
enc ? &ctx->enc_key : &ctx->dec_key,
walk.iv, enc);
disable_kernel_vsx();
pagefault_enable();
preempt_enable();
ret = skcipher_walk_done(&walk, nbytes % AES_BLOCK_SIZE);
}
return ret;
}
static int p8_aes_cbc_encrypt(struct skcipher_request *req)
{
return p8_aes_cbc_crypt(req, 1);
}
static int p8_aes_cbc_decrypt(struct skcipher_request *req)
{
return p8_aes_cbc_crypt(req, 0);
}
struct skcipher_alg p8_aes_cbc_alg = {
.base.cra_name = "cbc(aes)",
.base.cra_driver_name = "p8_aes_cbc",
.base.cra_module = THIS_MODULE,
.base.cra_priority = 2000,
.base.cra_flags = CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = AES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct p8_aes_cbc_ctx),
.setkey = p8_aes_cbc_setkey,
.encrypt = p8_aes_cbc_encrypt,
.decrypt = p8_aes_cbc_decrypt,
.init = p8_aes_cbc_init,
.exit = p8_aes_cbc_exit,
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
};