arch/x86/crypto/ablk_helper.c

   1 /*
   2  * Shared async block cipher helpers
   3  *
   4  * Copyright (c) 2012 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
   5  *
   6  * Based on aesni-intel_glue.c by:
   7  *  Copyright (C) 2008, Intel Corp.
   8  *    Author: Huang Ying <ying.huang@intel.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  23  * USA
  24  *
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/crypto.h>
  29 #include <linux/init.h>
  30 #include <linux/module.h>
  31 #include <crypto/algapi.h>
  32 #include <crypto/cryptd.h>
  33 #include <asm/i387.h>
  34 #include <asm/crypto/ablk_helper.h>
  35
  36 int ablk_set_key(struct crypto_ablkcipher *tfm, const u8 *key,
  37                  unsigned int key_len)
  38 {
  39         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  40         struct crypto_ablkcipher *child = &ctx->cryptd_tfm->base;
  41         int err;
  42
  43         crypto_ablkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  44         crypto_ablkcipher_set_flags(child, crypto_ablkcipher_get_flags(tfm)
  45                                     & CRYPTO_TFM_REQ_MASK);
  46         err = crypto_ablkcipher_setkey(child, key, key_len);
  47         crypto_ablkcipher_set_flags(tfm, crypto_ablkcipher_get_flags(child)
  48                                     & CRYPTO_TFM_RES_MASK);
  49         return err;
  50 }
  51 EXPORT_SYMBOL_GPL(ablk_set_key);
  52
  53 int __ablk_encrypt(struct ablkcipher_request *req)
  54 {
  55         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  56         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  57         struct blkcipher_desc desc;
  58
  59         desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm);
  60         desc.info = req->info;
  61         desc.flags = 0;
  62
  63         return crypto_blkcipher_crt(desc.tfm)->encrypt(
  64                 &desc, req->dst, req->src, req->nbytes);
  65 }
  66 EXPORT_SYMBOL_GPL(__ablk_encrypt);
  67
  68 int ablk_encrypt(struct ablkcipher_request *req)
  69 {
  70         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  71         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  72
  73         if (!irq_fpu_usable()) {
  74                 struct ablkcipher_request *cryptd_req =
  75                         ablkcipher_request_ctx(req);
  76
  77                 memcpy(cryptd_req, req, sizeof(*req));
  78                 ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base);
  79
  80                 return crypto_ablkcipher_encrypt(cryptd_req);
  81         } else {
  82                 return __ablk_encrypt(req);
  83         }
  84 }
  85 EXPORT_SYMBOL_GPL(ablk_encrypt);
  86
  87 int ablk_decrypt(struct ablkcipher_request *req)
  88 {
  89         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  90         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  91
  92         if (!irq_fpu_usable()) {
  93                 struct ablkcipher_request *cryptd_req =
  94                         ablkcipher_request_ctx(req);
  95
  96                 memcpy(cryptd_req, req, sizeof(*req));
  97                 ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base);
  98
  99                 return crypto_ablkcipher_decrypt(cryptd_req);
 100         } else {
 101                 struct blkcipher_desc desc;
 102
 103                 desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm);
 104                 desc.info = req->info;
 105                 desc.flags = 0;
 106
 107                 return crypto_blkcipher_crt(desc.tfm)->decrypt(
 108                         &desc, req->dst, req->src, req->nbytes);
 109         }
 110 }
 111 EXPORT_SYMBOL_GPL(ablk_decrypt);
 112
 113 void ablk_exit(struct crypto_tfm *tfm)
 114 {
 115         struct async_helper_ctx *ctx = crypto_tfm_ctx(tfm);
 116
 117         cryptd_free_ablkcipher(ctx->cryptd_tfm);
 118 }
 119 EXPORT_SYMBOL_GPL(ablk_exit);
 120
 121 int ablk_init_common(struct crypto_tfm *tfm, const char *drv_name)
 122 {
 123         struct async_helper_ctx *ctx = crypto_tfm_ctx(tfm);
 124         struct cryptd_ablkcipher *cryptd_tfm;
 125
 126         cryptd_tfm = cryptd_alloc_ablkcipher(drv_name, 0, 0);
 127         if (IS_ERR(cryptd_tfm))
 128                 return PTR_ERR(cryptd_tfm);
 129
 130         ctx->cryptd_tfm = cryptd_tfm;
 131         tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request) +
 132                 crypto_ablkcipher_reqsize(&cryptd_tfm->base);
 133
 134         return 0;
 135 }
 136 EXPORT_SYMBOL_GPL(ablk_init_common);
 137
 138 int ablk_init(struct crypto_tfm *tfm)
 139 {
 140         char drv_name[CRYPTO_MAX_ALG_NAME];
 141
 142         snprintf(drv_name, sizeof(drv_name), "__driver-%s",
 143                                         crypto_tfm_alg_driver_name(tfm));
 144
 145         return ablk_init_common(tfm, drv_name);
 146 }
 147 EXPORT_SYMBOL_GPL(ablk_init);
 148
 149 MODULE_LICENSE("GPL");