From: Marcelo H. Cerri Date: Fri, 6 Feb 2015 16:57:53 +0000 (-0200) Subject: crypto: vmx - Adding CBC routines for VMX module X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=8c755ace357c77fbfea61a2ce07d9723a9bb482f;p=linux-beck.git crypto: vmx - Adding CBC routines for VMX module This patch adds AES CBC routines to VMX module in order to make use of VMX cryptographic acceleration instructions on Power 8 CPU. Signed-off-by: Leonidas S. Barbosa Signed-off-by: Herbert Xu --- diff --git a/drivers/crypto/vmx/aes_cbc.c b/drivers/crypto/vmx/aes_cbc.c new file mode 100644 index 000000000000..1a559b7dddb5 --- /dev/null +++ b/drivers/crypto/vmx/aes_cbc.c @@ -0,0 +1,184 @@ +/** + * AES CBC routines supporting VMX instructions on the 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 Foundation; 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 or FITNESS FOR A PARTICULAR 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: Marcelo Henrique Cerri + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "aesp8-ppc.h" + +struct p8_aes_cbc_ctx { + struct crypto_blkcipher *fallback; + struct aes_key enc_key; + struct aes_key dec_key; +}; + +static int p8_aes_cbc_init(struct crypto_tfm *tfm) +{ + const char *alg; + struct crypto_blkcipher *fallback; + struct p8_aes_cbc_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_cbc_exit(struct crypto_tfm *tfm) +{ + struct p8_aes_cbc_ctx *ctx = crypto_tfm_ctx(tfm); + + if (ctx->fallback) { + crypto_free_blkcipher(ctx->fallback); + ctx->fallback = NULL; + } +} + +static int p8_aes_cbc_setkey(struct crypto_tfm *tfm, const u8 *key, + unsigned int keylen) +{ + int ret; + struct p8_aes_cbc_ctx *ctx = crypto_tfm_ctx(tfm); + + pagefault_disable(); + enable_kernel_altivec(); + ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key); + ret += aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key); + pagefault_enable(); + + ret += crypto_blkcipher_setkey(ctx->fallback, key, keylen); + return ret; +} + +static int p8_aes_cbc_encrypt(struct blkcipher_desc *desc, + struct scatterlist *dst, struct scatterlist *src, + unsigned int nbytes) +{ + int ret; + struct blkcipher_walk walk; + struct p8_aes_cbc_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 = crypto_blkcipher_encrypt(&fallback_desc, dst, src, nbytes); + } else { + pagefault_disable(); + enable_kernel_altivec(); + + blkcipher_walk_init(&walk, dst, src, nbytes); + ret = blkcipher_walk_virt(desc, &walk); + while ((nbytes = walk.nbytes)) { + aes_p8_cbc_encrypt(walk.src.virt.addr, walk.dst.virt.addr, + nbytes & AES_BLOCK_MASK, &ctx->enc_key, walk.iv, 1); + nbytes &= AES_BLOCK_SIZE - 1; + ret = blkcipher_walk_done(desc, &walk, nbytes); + } + + pagefault_enable(); + } + + return ret; +} + +static int p8_aes_cbc_decrypt(struct blkcipher_desc *desc, + struct scatterlist *dst, struct scatterlist *src, + unsigned int nbytes) +{ + int ret; + struct blkcipher_walk walk; + struct p8_aes_cbc_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 = crypto_blkcipher_decrypt(&fallback_desc, dst, src, nbytes); + } else { + pagefault_disable(); + enable_kernel_altivec(); + + blkcipher_walk_init(&walk, dst, src, nbytes); + ret = blkcipher_walk_virt(desc, &walk); + while ((nbytes = walk.nbytes)) { + aes_p8_cbc_encrypt(walk.src.virt.addr, walk.dst.virt.addr, + nbytes & AES_BLOCK_MASK, &ctx->dec_key, walk.iv, 0); + nbytes &= AES_BLOCK_SIZE - 1; + ret = blkcipher_walk_done(desc, &walk, nbytes); + } + + pagefault_enable(); + } + + return ret; +} + + +struct crypto_alg p8_aes_cbc_alg = { + .cra_name = "cbc(aes)", + .cra_driver_name = "p8_aes_cbc", + .cra_module = THIS_MODULE, + .cra_priority = 1000, + .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_cbc_ctx), + .cra_init = p8_aes_cbc_init, + .cra_exit = p8_aes_cbc_exit, + .cra_blkcipher = { + .ivsize = 0, + .min_keysize = AES_MIN_KEY_SIZE, + .max_keysize = AES_MAX_KEY_SIZE, + .setkey = p8_aes_cbc_setkey, + .encrypt = p8_aes_cbc_encrypt, + .decrypt = p8_aes_cbc_decrypt, + }, +}; +