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, see <http://www.gnu.org/licenses/>.
  22  *
  23  */
  24
  25 #include <linux/kernel.h>
  26 #include <linux/crypto.h>
  27 #include <linux/init.h>
  28 #include <linux/module.h>
  29 #include <crypto/algapi.h>
  30 #include <crypto/cryptd.h>
  31 #include <crypto/ablk_helper.h>
  32 #include <asm/simd.h>
  33
  34 int ablk_set_key(struct crypto_ablkcipher *tfm, const u8 *key,
  35                  unsigned int key_len)
  36 {
  37         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  38         struct crypto_ablkcipher *child = &ctx->cryptd_tfm->base;
  39         int err;
  40
  41         crypto_ablkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  42         crypto_ablkcipher_set_flags(child, crypto_ablkcipher_get_flags(tfm)
  43                                     & CRYPTO_TFM_REQ_MASK);
  44         err = crypto_ablkcipher_setkey(child, key, key_len);
  45         crypto_ablkcipher_set_flags(tfm, crypto_ablkcipher_get_flags(child)
  46                                     & CRYPTO_TFM_RES_MASK);
  47         return err;
  48 }
  49 EXPORT_SYMBOL_GPL(ablk_set_key);
  50
  51 int __ablk_encrypt(struct ablkcipher_request *req)
  52 {
  53         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  54         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  55         struct blkcipher_desc desc;
  56
  57         desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm);
  58         desc.info = req->info;
  59         desc.flags = 0;
  60
  61         return crypto_blkcipher_crt(desc.tfm)->encrypt(
  62                 &desc, req->dst, req->src, req->nbytes);
  63 }
  64 EXPORT_SYMBOL_GPL(__ablk_encrypt);
  65
  66 int ablk_encrypt(struct ablkcipher_request *req)
  67 {
  68         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  69         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  70
  71         if (!may_use_simd() ||
  72             (in_atomic() && cryptd_ablkcipher_queued(ctx->cryptd_tfm))) {
  73                 struct ablkcipher_request *cryptd_req =
  74                         ablkcipher_request_ctx(req);
  75
  76                 *cryptd_req = *req;
  77                 ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base);
  78
  79                 return crypto_ablkcipher_encrypt(cryptd_req);
  80         } else {
  81                 return __ablk_encrypt(req);
  82         }
  83 }
  84 EXPORT_SYMBOL_GPL(ablk_encrypt);
  85
  86 int ablk_decrypt(struct ablkcipher_request *req)
  87 {
  88         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
  89         struct async_helper_ctx *ctx = crypto_ablkcipher_ctx(tfm);
  90
  91         if (!may_use_simd() ||
  92             (in_atomic() && cryptd_ablkcipher_queued(ctx->cryptd_tfm))) {
  93                 struct ablkcipher_request *cryptd_req =
  94                         ablkcipher_request_ctx(req);
  95
  96                 *cryptd_req = *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, CRYPTO_ALG_INTERNAL,
 127                                              CRYPTO_ALG_INTERNAL);
 128         if (IS_ERR(cryptd_tfm))
 129                 return PTR_ERR(cryptd_tfm);
 130
 131         ctx->cryptd_tfm = cryptd_tfm;
 132         tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request) +
 133                 crypto_ablkcipher_reqsize(&cryptd_tfm->base);
 134
 135         return 0;
 136 }
 137 EXPORT_SYMBOL_GPL(ablk_init_common);
 138
 139 int ablk_init(struct crypto_tfm *tfm)
 140 {
 141         char drv_name[CRYPTO_MAX_ALG_NAME];
 142
 143         snprintf(drv_name, sizeof(drv_name), "__driver-%s",
 144                                         crypto_tfm_alg_driver_name(tfm));
 145
 146         return ablk_init_common(tfm, drv_name);
 147 }
 148 EXPORT_SYMBOL_GPL(ablk_init);
 149
 150 MODULE_LICENSE("GPL");