From: Stephan Mueller Subject: Re: [PATCH 2/2] crypto: vmx - Adding support for XTS Date: Mon, 11 Jul 2016 22:10:39 +0200 Message-ID: <3796236.yVu684LHdL@positron.chronox.de> References: <1468264060-22769-1-git-send-email-pfsmorigo@linux.vnet.ibm.com> <1468264060-22769-2-git-send-email-pfsmorigo@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: linux-kernel@vger.kernel.org, "Leonidas S. Barbosa" , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Herbert Xu , "David S. Miller" , "open list:IBM Power VMX Cryptographic instructions" , "open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)" To: Paulo Flabiano Smorigo Return-path: Received: from mail.eperm.de ([89.247.134.16]:38914 "EHLO mail.eperm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751191AbcGKUKp (ORCPT ); Mon, 11 Jul 2016 16:10:45 -0400 In-Reply-To: <1468264060-22769-2-git-send-email-pfsmorigo@linux.vnet.ibm.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: Am Montag, 11. Juli 2016, 16:07:40 CEST schrieb Paulo Flabiano Smorigo: Hi Paulo, > From: "Leonidas S. Barbosa" > > This patch add XTS support using VMX-crypto driver. > > Signed-off-by: Leonidas S. Barbosa > Signed-off-by: Paulo Flabiano Smorigo > --- > drivers/crypto/vmx/Makefile | 2 +- > drivers/crypto/vmx/aes_xts.c | 187 > +++++++++++++++++++++++++++++++++++++++++++ drivers/crypto/vmx/vmx.c | > 2 + > 3 files changed, 190 insertions(+), 1 deletion(-) > create mode 100644 drivers/crypto/vmx/aes_xts.c > > diff --git a/drivers/crypto/vmx/Makefile b/drivers/crypto/vmx/Makefile > index d28ab96..de6e241 100644 > --- a/drivers/crypto/vmx/Makefile > +++ b/drivers/crypto/vmx/Makefile > @@ -1,5 +1,5 @@ > obj-$(CONFIG_CRYPTO_DEV_VMX_ENCRYPT) += vmx-crypto.o > -vmx-crypto-objs := vmx.o aesp8-ppc.o ghashp8-ppc.o aes.o aes_cbc.o > aes_ctr.o ghash.o +vmx-crypto-objs := vmx.o aesp8-ppc.o ghashp8-ppc.o aes.o > aes_cbc.o aes_ctr.o aes_xts.o ghash.o > > ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y) > TARGET := linux-ppc64le > diff --git a/drivers/crypto/vmx/aes_xts.c b/drivers/crypto/vmx/aes_xts.c > new file mode 100644 > index 0000000..62e698c > --- /dev/null > +++ b/drivers/crypto/vmx/aes_xts.c > @@ -0,0 +1,187 @@ > +/** > + * AES XTS routines supporting VMX In-core instructions on Power 8 > + * > + * Copyright (C) 2015 International Business Machines Inc. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundations; version 2 only. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY of FITNESS FOR A PARTICUPAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. > + * > + * Author: Leonidas S. Barbosa > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include "aesp8-ppc.h" > + > +struct p8_aes_xts_ctx { > + struct crypto_blkcipher *fallback; > + struct aes_key enc_key; > + struct aes_key dec_key; > + struct aes_key tweak_key; > +}; > + > +static int p8_aes_xts_init(struct crypto_tfm *tfm) > +{ > + const char *alg; > + struct crypto_blkcipher *fallback; > + struct p8_aes_xts_ctx *ctx = crypto_tfm_ctx(tfm); > + > + if (!(alg = crypto_tfm_alg_name(tfm))) { > + printk(KERN_ERR "Failed to get algorithm name.\n"); > + return -ENOENT; > + } > + > + fallback = > + crypto_alloc_blkcipher(alg, 0, CRYPTO_ALG_NEED_FALLBACK); > + if (IS_ERR(fallback)) { > + printk(KERN_ERR > + "Failed to allocate transformation for '%s': %ld\n", > + alg, PTR_ERR(fallback)); > + return PTR_ERR(fallback); > + } > + printk(KERN_INFO "Using '%s' as fallback implementation.\n", > + crypto_tfm_alg_driver_name((struct crypto_tfm *) fallback)); > + > + crypto_blkcipher_set_flags( > + fallback, > + crypto_blkcipher_get_flags((struct crypto_blkcipher *)tfm)); > + ctx->fallback = fallback; > + > + return 0; > +} > + > +static void p8_aes_xts_exit(struct crypto_tfm *tfm) > +{ > + struct p8_aes_xts_ctx *ctx = crypto_tfm_ctx(tfm); > + > + if (ctx->fallback) { > + crypto_free_blkcipher(ctx->fallback); > + ctx->fallback = NULL; > + } > +} > + > +static int p8_aes_xts_setkey(struct crypto_tfm *tfm, const u8 *key, > + unsigned int keylen) > +{ > + int ret; > + struct p8_aes_xts_ctx *ctx = crypto_tfm_ctx(tfm); > + > + if (keylen % 2) > + return -EINVAL; Please use xts_check_key instead of this check. > + > + preempt_disable(); > + pagefault_disable(); > + enable_kernel_vsx(); > + ret = aes_p8_set_encrypt_key(key + keylen/2, (keylen/2) * 8, > &ctx->tweak_key); + ret += aes_p8_set_encrypt_key(key, (keylen/2) * 8, > &ctx->enc_key); + ret += aes_p8_set_decrypt_key(key, (keylen/2) * 8, > &ctx->dec_key); + disable_kernel_vsx(); > + pagefault_enable(); > + preempt_enable(); > + > + ret += crypto_blkcipher_setkey(ctx->fallback, key, keylen); > + return ret; > +} > + > +static int p8_aes_xts_crypt(struct blkcipher_desc *desc, > + struct scatterlist *dst, > + struct scatterlist *src, > + unsigned int nbytes, int enc) > +{ > + int ret; > + u8 tweak[AES_BLOCK_SIZE]; > + u8 *iv; > + struct blkcipher_walk walk; > + struct p8_aes_xts_ctx *ctx = > + crypto_tfm_ctx(crypto_blkcipher_tfm(desc->tfm)); > + struct blkcipher_desc fallback_desc = { > + .tfm = ctx->fallback, > + .info = desc->info, > + .flags = desc->flags > + }; > + > + if (in_interrupt()) { > + ret = enc ? crypto_blkcipher_encrypt(&fallback_desc, dst, src, nbytes) : > + crypto_blkcipher_decrypt(&fallback_desc, dst, > src, nbytes); + } else { > + preempt_disable(); > + pagefault_disable(); > + enable_kernel_vsx(); > + > + blkcipher_walk_init(&walk, dst, src, nbytes); > + > + iv = (u8 *)walk.iv; > + ret = blkcipher_walk_virt(desc, &walk); > + aes_p8_encrypt(iv, tweak, &ctx->tweak_key); > + > + while ((nbytes = walk.nbytes)) { > + if (enc) > + aes_p8_xts_encrypt(walk.src.virt.addr, walk.dst.virt.addr, > + nbytes & AES_BLOCK_MASK, &ctx->enc_key, NULL, tweak); > + else > + aes_p8_xts_decrypt(walk.src.virt.addr, walk.dst.virt.addr, > + nbytes & AES_BLOCK_MASK, &ctx->dec_key, NULL, tweak); > + > + nbytes &= AES_BLOCK_SIZE - 1; > + ret = blkcipher_walk_done(desc, &walk, nbytes); > + } > + > + disable_kernel_vsx(); > + pagefault_enable(); > + preempt_enable(); memzero_explicit(tweak) ? > + } > + return ret; > +} > + > +static int p8_aes_xts_encrypt(struct blkcipher_desc *desc, > + struct scatterlist *dst, > + struct scatterlist *src, unsigned int nbytes) > +{ > + return p8_aes_xts_crypt(desc, dst, src, nbytes, 1); > +} > + > +static int p8_aes_xts_decrypt(struct blkcipher_desc *desc, > + struct scatterlist *dst, > + struct scatterlist *src, unsigned int nbytes) > +{ > + return p8_aes_xts_crypt(desc, dst, src, nbytes, 0); > +} > + > +struct crypto_alg p8_aes_xts_alg = { > + .cra_name = "xts(aes)", > + .cra_driver_name = "p8_aes_xts", > + .cra_module = THIS_MODULE, > + .cra_priority = 2000, > + .cra_type = &crypto_blkcipher_type, > + .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | CRYPTO_ALG_NEED_FALLBACK, > + .cra_alignmask = 0, > + .cra_blocksize = AES_BLOCK_SIZE, > + .cra_ctxsize = sizeof(struct p8_aes_xts_ctx), > + .cra_init = p8_aes_xts_init, > + .cra_exit = p8_aes_xts_exit, > + .cra_blkcipher = { > + .ivsize = AES_BLOCK_SIZE, > + .min_keysize = 2 * AES_MIN_KEY_SIZE, > + .max_keysize = 2 * AES_MAX_KEY_SIZE, > + .setkey = p8_aes_xts_setkey, > + .encrypt = p8_aes_xts_encrypt, > + .decrypt = p8_aes_xts_decrypt, > + } > +}; > diff --git a/drivers/crypto/vmx/vmx.c b/drivers/crypto/vmx/vmx.c > index e163d57..f688c32 100644 > --- a/drivers/crypto/vmx/vmx.c > +++ b/drivers/crypto/vmx/vmx.c > @@ -31,10 +31,12 @@ extern struct shash_alg p8_ghash_alg; > extern struct crypto_alg p8_aes_alg; > extern struct crypto_alg p8_aes_cbc_alg; > extern struct crypto_alg p8_aes_ctr_alg; > +extern struct crypto_alg p8_aes_xts_alg; > static struct crypto_alg *algs[] = { > &p8_aes_alg, > &p8_aes_cbc_alg, > &p8_aes_ctr_alg, > + &p8_aes_xts_alg, > NULL, > }; Ciao Stephan