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 <linux/hardirq.h>
  32 #include <crypto/algapi.h>
  33 #include <crypto/cryptd.h>
  34 #include <crypto/ablk_helper.h>
  35 #include <asm/simd.h>
  36
  37 int ablk_set_key(struct crypto_ablkcipher *tfm, const u8 *key,
  38                  unsigned int key_len)
  39 {
  40         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  41         struct crypto_ablkcipher *child = &ctx->cryptd_tfm->base;
  42         int err;
  43
  44         crypto_ablkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  45         crypto_ablkcipher_set_flags(child, crypto_ablkcipher_get_flags(tfm)
  46                                     & CRYPTO_TFM_REQ_MASK);
  47         err = crypto_ablkcipher_setkey(child, key, key_len);
  48         crypto_ablkcipher_set_flags(tfm, crypto_ablkcipher_get_flags(child)
  49                                     & CRYPTO_TFM_RES_MASK);
  50         return err;
  51 }
  52 EXPORT_SYMBOL_GPL(ablk_set_key);
  53
  54 int __ablk_encrypt(struct ablkcipher_request *req)
  55 {
  56         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  57         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  58         struct blkcipher_desc desc;
  59
  60         desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm);
  61         desc.info = req->info;
  62         desc.flags = 0;
  63
  64         return crypto_blkcipher_crt(desc.tfm)->encrypt(
  65                 &desc, req->dst, req->src, req->nbytes);
  66 }
  67 EXPORT_SYMBOL_GPL(__ablk_encrypt);
  68
  69 int ablk_encrypt(struct ablkcipher_request *req)
  70 {
  71         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  72         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  73
  74         if (!may_use_simd()) {
  75                 struct ablkcipher_request *cryptd_req =
  76                         ablkcipher_request_ctx(req);
  77
  78                 *cryptd_req = *req;
  79                 ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base);
  80
  81                 return crypto_ablkcipher_encrypt(cryptd_req);
  82         } else {
  83                 return __ablk_encrypt(req);
  84         }
  85 }
  86 EXPORT_SYMBOL_GPL(ablk_encrypt);
  87
  88 int ablk_decrypt(struct ablkcipher_request *req)
  89 {
  90         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  91         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  92
  93         if (!may_use_simd()) {
  94                 struct ablkcipher_request *cryptd_req =
  95                         ablkcipher_request_ctx(req);
  96
  97                 *cryptd_req = *req;
  98                 ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base);
  99
 100                 return crypto_ablkcipher_decrypt(cryptd_req);
 101         } else {
 102                 struct blkcipher_desc desc;
 103
 104                 desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm);
 105                 desc.info = req->info;
 106                 desc.flags = 0;
 107
 108                 return crypto_blkcipher_crt(desc.tfm)->decrypt(
 109                         &desc, req->dst, req->src, req->nbytes);
 110         }
 111 }
 112 EXPORT_SYMBOL_GPL(ablk_decrypt);
 113
 114 void ablk_exit(struct crypto_tfm *tfm)
 115 {
 116         struct async_helper_ctx *ctx = crypto_tfm_ctx(tfm);
 117
 118         cryptd_free_ablkcipher(ctx->cryptd_tfm);
 119 }
 120 EXPORT_SYMBOL_GPL(ablk_exit);
 121
 122 int ablk_init_common(struct crypto_tfm *tfm, const char *drv_name)
 123 {
 124         struct async_helper_ctx *ctx = crypto_tfm_ctx(tfm);
 125         struct cryptd_ablkcipher *cryptd_tfm;
 126
 127         cryptd_tfm = cryptd_alloc_ablkcipher(drv_name, CRYPTO_ALG_INTERNAL,
 128                                              CRYPTO_ALG_INTERNAL);
 129         if (IS_ERR(cryptd_tfm))
 130                 return PTR_ERR(cryptd_tfm);
 131
 132         ctx->cryptd_tfm = cryptd_tfm;
 133         tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request) +
 134                 crypto_ablkcipher_reqsize(&cryptd_tfm->base);
 135
 136         return 0;
 137 }
 138 EXPORT_SYMBOL_GPL(ablk_init_common);
 139
 140 int ablk_init(struct crypto_tfm *tfm)
 141 {
 142         char drv_name[CRYPTO_MAX_ALG_NAME];
 143
 144         snprintf(drv_name, sizeof(drv_name), "__driver-%s",
 145                                         crypto_tfm_alg_driver_name(tfm));
 146
 147         return ablk_init_common(tfm, drv_name);
 148 }
 149 EXPORT_SYMBOL_GPL(ablk_init);
 150
 151 MODULE_LICENSE("GPL");