diff options
Diffstat (limited to 'arch/x86/crypto/glue_helper.c')
-rw-r--r-- | arch/x86/crypto/glue_helper.c | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/arch/x86/crypto/glue_helper.c b/arch/x86/crypto/glue_helper.c new file mode 100644 index 000000000000..4854f0f31e4f --- /dev/null +++ b/arch/x86/crypto/glue_helper.c @@ -0,0 +1,307 @@ +/* + * Shared glue code for 128bit block ciphers + * + * Copyright (c) 2012 Jussi Kivilinna <jussi.kivilinna@mbnet.fi> + * + * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by: + * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> + * CTR part based on code (crypto/ctr.c) by: + * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com> + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 + * USA + * + */ + +#include <linux/module.h> +#include <crypto/b128ops.h> +#include <crypto/lrw.h> +#include <crypto/xts.h> +#include <asm/crypto/glue_helper.h> +#include <crypto/scatterwalk.h> + +static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx, + struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + void *ctx = crypto_blkcipher_ctx(desc->tfm); + const unsigned int bsize = 128 / 8; + unsigned int nbytes, i, func_bytes; + bool fpu_enabled = false; + int err; + + err = blkcipher_walk_virt(desc, walk); + + while ((nbytes = walk->nbytes)) { + u8 *wsrc = walk->src.virt.addr; + u8 *wdst = walk->dst.virt.addr; + + fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, + desc, fpu_enabled, nbytes); + + for (i = 0; i < gctx->num_funcs; i++) { + func_bytes = bsize * gctx->funcs[i].num_blocks; + + /* Process multi-block batch */ + if (nbytes >= func_bytes) { + do { + gctx->funcs[i].fn_u.ecb(ctx, wdst, + wsrc); + + wsrc += func_bytes; + wdst += func_bytes; + nbytes -= func_bytes; + } while (nbytes >= func_bytes); + + if (nbytes < bsize) + goto done; + } + } + +done: + err = blkcipher_walk_done(desc, walk, nbytes); + } + + glue_fpu_end(fpu_enabled); + return err; +} + +int glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx, + struct blkcipher_desc *desc, struct scatterlist *dst, + struct scatterlist *src, unsigned int nbytes) +{ + struct blkcipher_walk walk; + + blkcipher_walk_init(&walk, dst, src, nbytes); + return __glue_ecb_crypt_128bit(gctx, desc, &walk); +} +EXPORT_SYMBOL_GPL(glue_ecb_crypt_128bit); + +static unsigned int __glue_cbc_encrypt_128bit(const common_glue_func_t fn, + struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + void *ctx = crypto_blkcipher_ctx(desc->tfm); + const unsigned int bsize = 128 / 8; + unsigned int nbytes = walk->nbytes; + u128 *src = (u128 *)walk->src.virt.addr; + u128 *dst = (u128 *)walk->dst.virt.addr; + u128 *iv = (u128 *)walk->iv; + + do { + u128_xor(dst, src, iv); + fn(ctx, (u8 *)dst, (u8 *)dst); + iv = dst; + + src += 1; + dst += 1; + nbytes -= bsize; + } while (nbytes >= bsize); + + u128_xor((u128 *)walk->iv, (u128 *)walk->iv, iv); + return nbytes; +} + +int glue_cbc_encrypt_128bit(const common_glue_func_t fn, + struct blkcipher_desc *desc, + struct scatterlist *dst, + struct scatterlist *src, unsigned int nbytes) +{ + struct blkcipher_walk walk; + int err; + + blkcipher_walk_init(&walk, dst, src, nbytes); + err = blkcipher_walk_virt(desc, &walk); + + while ((nbytes = walk.nbytes)) { + nbytes = __glue_cbc_encrypt_128bit(fn, desc, &walk); + err = blkcipher_walk_done(desc, &walk, nbytes); + } + + return err; +} +EXPORT_SYMBOL_GPL(glue_cbc_encrypt_128bit); + +static unsigned int +__glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx, + struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + void *ctx = crypto_blkcipher_ctx(desc->tfm); + const unsigned int bsize = 128 / 8; + unsigned int nbytes = walk->nbytes; + u128 *src = (u128 *)walk->src.virt.addr; + u128 *dst = (u128 *)walk->dst.virt.addr; + u128 last_iv; + unsigned int num_blocks, func_bytes; + unsigned int i; + + /* Start of the last block. */ + src += nbytes / bsize - 1; + dst += nbytes / bsize - 1; + + last_iv = *src; + + for (i = 0; i < gctx->num_funcs; i++) { + num_blocks = gctx->funcs[i].num_blocks; + func_bytes = bsize * num_blocks; + + /* Process multi-block batch */ + if (nbytes >= func_bytes) { + do { + nbytes -= func_bytes - bsize; + src -= num_blocks - 1; + dst -= num_blocks - 1; + + gctx->funcs[i].fn_u.cbc(ctx, dst, src); + + nbytes -= bsize; + if (nbytes < bsize) + goto done; + + u128_xor(dst, dst, src - 1); + src -= 1; + dst -= 1; + } while (nbytes >= func_bytes); + + if (nbytes < bsize) + goto done; + } + } + +done: + u128_xor(dst, dst, (u128 *)walk->iv); + *(u128 *)walk->iv = last_iv; + + return nbytes; +} + +int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx, + struct blkcipher_desc *desc, + struct scatterlist *dst, + struct scatterlist *src, unsigned int nbytes) +{ + const unsigned int bsize = 128 / 8; + bool fpu_enabled = false; + struct blkcipher_walk walk; + int err; + + blkcipher_walk_init(&walk, dst, src, nbytes); + err = blkcipher_walk_virt(desc, &walk); + + while ((nbytes = walk.nbytes)) { + fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, + desc, fpu_enabled, nbytes); + nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk); + err = blkcipher_walk_done(desc, &walk, nbytes); + } + + glue_fpu_end(fpu_enabled); + return err; +} +EXPORT_SYMBOL_GPL(glue_cbc_decrypt_128bit); + +static void glue_ctr_crypt_final_128bit(const common_glue_ctr_func_t fn_ctr, + struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + void *ctx = crypto_blkcipher_ctx(desc->tfm); + u8 *src = (u8 *)walk->src.virt.addr; + u8 *dst = (u8 *)walk->dst.virt.addr; + unsigned int nbytes = walk->nbytes; + u128 ctrblk; + u128 tmp; + + be128_to_u128(&ctrblk, (be128 *)walk->iv); + + memcpy(&tmp, src, nbytes); + fn_ctr(ctx, &tmp, &tmp, &ctrblk); + memcpy(dst, &tmp, nbytes); + + u128_to_be128((be128 *)walk->iv, &ctrblk); +} +EXPORT_SYMBOL_GPL(glue_ctr_crypt_final_128bit); + +static unsigned int __glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx, + struct blkcipher_desc *desc, + struct blkcipher_walk *walk) +{ + const unsigned int bsize = 128 / 8; + void *ctx = crypto_blkcipher_ctx(desc->tfm); + unsigned int nbytes = walk->nbytes; + u128 *src = (u128 *)walk->src.virt.addr; + u128 *dst = (u128 *)walk->dst.virt.addr; + u128 ctrblk; + unsigned int num_blocks, func_bytes; + unsigned int i; + + be128_to_u128(&ctrblk, (be128 *)walk->iv); + + /* Process multi-block batch */ + for (i = 0; i < gctx->num_funcs; i++) { + num_blocks = gctx->funcs[i].num_blocks; + func_bytes = bsize * num_blocks; + + if (nbytes >= func_bytes) { + do { + gctx->funcs[i].fn_u.ctr(ctx, dst, src, &ctrblk); + + src += num_blocks; + dst += num_blocks; + nbytes -= func_bytes; + } while (nbytes >= func_bytes); + + if (nbytes < bsize) + goto done; + } + } + +done: + u128_to_be128((be128 *)walk->iv, &ctrblk); + return nbytes; +} + +int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx, + struct blkcipher_desc *desc, struct scatterlist *dst, + struct scatterlist *src, unsigned int nbytes) +{ + const unsigned int bsize = 128 / 8; + bool fpu_enabled = false; + struct blkcipher_walk walk; + int err; + + blkcipher_walk_init(&walk, dst, src, nbytes); + err = blkcipher_walk_virt_block(desc, &walk, bsize); + + while ((nbytes = walk.nbytes) >= bsize) { + fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, + desc, fpu_enabled, nbytes); + nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk); + err = blkcipher_walk_done(desc, &walk, nbytes); + } + + glue_fpu_end(fpu_enabled); + + if (walk.nbytes) { + glue_ctr_crypt_final_128bit( + gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk); + err = blkcipher_walk_done(desc, &walk, 0); + } + + return err; +} +EXPORT_SYMBOL_GPL(glue_ctr_crypt_128bit); + +MODULE_LICENSE("GPL"); |