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Leonidas S. Barbosaherbertx
Leonidas S. Barbosa
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herbertx
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crypto: vmx - Adding support for XTS
This patch add XTS support using VMX-crypto driver. Signed-off-by: Leonidas S. Barbosa <[email protected]> Signed-off-by: Paulo Flabiano Smorigo <[email protected]> Signed-off-by: Herbert Xu <[email protected]>
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‎drivers/crypto/vmx/Makefile

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
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obj-$(CONFIG_CRYPTO_DEV_VMX_ENCRYPT) += vmx-crypto.o
2-
vmx-crypto-objs := vmx.o aesp8-ppc.o ghashp8-ppc.o aes.o aes_cbc.o aes_ctr.o ghash.o
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vmx-crypto-objs := vmx.o aesp8-ppc.o ghashp8-ppc.o aes.o aes_cbc.o aes_ctr.o aes_xts.o ghash.o
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44
ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y)
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TARGET := linux-ppc64le

‎drivers/crypto/vmx/aes_xts.c

Lines changed: 190 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,190 @@
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/**
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* AES XTS routines supporting VMX In-core instructions on Power 8
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*
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* Copyright (C) 2015 International Business Machines Inc.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundations; version 2 only.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY of FITNESS FOR A PARTICUPAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*
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* Author: Leonidas S. Barbosa <[email protected]>
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*/
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#include <linux/types.h>
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#include <linux/err.h>
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#include <linux/crypto.h>
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#include <linux/delay.h>
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#include <linux/hardirq.h>
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#include <asm/switch_to.h>
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#include <crypto/aes.h>
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#include <crypto/scatterwalk.h>
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#include <crypto/xts.h>
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#include "aesp8-ppc.h"
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struct p8_aes_xts_ctx {
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struct crypto_blkcipher *fallback;
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struct aes_key enc_key;
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struct aes_key dec_key;
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struct aes_key tweak_key;
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};
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static int p8_aes_xts_init(struct crypto_tfm *tfm)
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{
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const char *alg;
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struct crypto_blkcipher *fallback;
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struct p8_aes_xts_ctx *ctx = crypto_tfm_ctx(tfm);
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if (!(alg = crypto_tfm_alg_name(tfm))) {
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printk(KERN_ERR "Failed to get algorithm name.\n");
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return -ENOENT;
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}
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fallback =
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crypto_alloc_blkcipher(alg, 0, CRYPTO_ALG_NEED_FALLBACK);
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if (IS_ERR(fallback)) {
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printk(KERN_ERR
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"Failed to allocate transformation for '%s': %ld\n",
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alg, PTR_ERR(fallback));
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return PTR_ERR(fallback);
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}
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printk(KERN_INFO "Using '%s' as fallback implementation.\n",
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crypto_tfm_alg_driver_name((struct crypto_tfm *) fallback));
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crypto_blkcipher_set_flags(
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fallback,
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crypto_blkcipher_get_flags((struct crypto_blkcipher *)tfm));
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ctx->fallback = fallback;
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return 0;
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}
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static void p8_aes_xts_exit(struct crypto_tfm *tfm)
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{
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struct p8_aes_xts_ctx *ctx = crypto_tfm_ctx(tfm);
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if (ctx->fallback) {
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crypto_free_blkcipher(ctx->fallback);
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ctx->fallback = NULL;
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}
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}
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static int p8_aes_xts_setkey(struct crypto_tfm *tfm, const u8 *key,
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unsigned int keylen)
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{
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int ret;
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struct p8_aes_xts_ctx *ctx = crypto_tfm_ctx(tfm);
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ret = xts_check_key(tfm, key, keylen);
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if (ret)
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return ret;
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preempt_disable();
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pagefault_disable();
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enable_kernel_vsx();
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ret = aes_p8_set_encrypt_key(key + keylen/2, (keylen/2) * 8, &ctx->tweak_key);
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ret += aes_p8_set_encrypt_key(key, (keylen/2) * 8, &ctx->enc_key);
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ret += aes_p8_set_decrypt_key(key, (keylen/2) * 8, &ctx->dec_key);
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disable_kernel_vsx();
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pagefault_enable();
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preempt_enable();
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ret += crypto_blkcipher_setkey(ctx->fallback, key, keylen);
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return ret;
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}
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static int p8_aes_xts_crypt(struct blkcipher_desc *desc,
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struct scatterlist *dst,
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struct scatterlist *src,
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unsigned int nbytes, int enc)
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{
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int ret;
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u8 tweak[AES_BLOCK_SIZE];
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u8 *iv;
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struct blkcipher_walk walk;
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struct p8_aes_xts_ctx *ctx =
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crypto_tfm_ctx(crypto_blkcipher_tfm(desc->tfm));
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struct blkcipher_desc fallback_desc = {
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.tfm = ctx->fallback,
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.info = desc->info,
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.flags = desc->flags
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};
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if (in_interrupt()) {
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ret = enc ? crypto_blkcipher_encrypt(&fallback_desc, dst, src, nbytes) :
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crypto_blkcipher_decrypt(&fallback_desc, dst, src, nbytes);
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} else {
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preempt_disable();
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pagefault_disable();
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enable_kernel_vsx();
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blkcipher_walk_init(&walk, dst, src, nbytes);
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iv = (u8 *)walk.iv;
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ret = blkcipher_walk_virt(desc, &walk);
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memset(tweak, 0, AES_BLOCK_SIZE);
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aes_p8_encrypt(iv, tweak, &ctx->tweak_key);
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while ((nbytes = walk.nbytes)) {
138+
if (enc)
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aes_p8_xts_encrypt(walk.src.virt.addr, walk.dst.virt.addr,
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nbytes & AES_BLOCK_MASK, &ctx->enc_key, NULL, tweak);
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else
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aes_p8_xts_decrypt(walk.src.virt.addr, walk.dst.virt.addr,
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nbytes & AES_BLOCK_MASK, &ctx->dec_key, NULL, tweak);
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nbytes &= AES_BLOCK_SIZE - 1;
146+
ret = blkcipher_walk_done(desc, &walk, nbytes);
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}
148+
149+
disable_kernel_vsx();
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pagefault_enable();
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preempt_enable();
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}
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return ret;
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}
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static int p8_aes_xts_encrypt(struct blkcipher_desc *desc,
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struct scatterlist *dst,
158+
struct scatterlist *src, unsigned int nbytes)
159+
{
160+
return p8_aes_xts_crypt(desc, dst, src, nbytes, 1);
161+
}
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static int p8_aes_xts_decrypt(struct blkcipher_desc *desc,
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struct scatterlist *dst,
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struct scatterlist *src, unsigned int nbytes)
166+
{
167+
return p8_aes_xts_crypt(desc, dst, src, nbytes, 0);
168+
}
169+
170+
struct crypto_alg p8_aes_xts_alg = {
171+
.cra_name = "xts(aes)",
172+
.cra_driver_name = "p8_aes_xts",
173+
.cra_module = THIS_MODULE,
174+
.cra_priority = 2000,
175+
.cra_type = &crypto_blkcipher_type,
176+
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | CRYPTO_ALG_NEED_FALLBACK,
177+
.cra_alignmask = 0,
178+
.cra_blocksize = AES_BLOCK_SIZE,
179+
.cra_ctxsize = sizeof(struct p8_aes_xts_ctx),
180+
.cra_init = p8_aes_xts_init,
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.cra_exit = p8_aes_xts_exit,
182+
.cra_blkcipher = {
183+
.ivsize = AES_BLOCK_SIZE,
184+
.min_keysize = 2 * AES_MIN_KEY_SIZE,
185+
.max_keysize = 2 * AES_MAX_KEY_SIZE,
186+
.setkey = p8_aes_xts_setkey,
187+
.encrypt = p8_aes_xts_encrypt,
188+
.decrypt = p8_aes_xts_decrypt,
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}
190+
};

‎drivers/crypto/vmx/vmx.c

Lines changed: 2 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -31,10 +31,12 @@ extern struct shash_alg p8_ghash_alg;
3131
extern struct crypto_alg p8_aes_alg;
3232
extern struct crypto_alg p8_aes_cbc_alg;
3333
extern struct crypto_alg p8_aes_ctr_alg;
34+
extern struct crypto_alg p8_aes_xts_alg;
3435
static struct crypto_alg *algs[] = {
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&p8_aes_alg,
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&p8_aes_cbc_alg,
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&p8_aes_ctr_alg,
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&p8_aes_xts_alg,
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NULL,
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};
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