crypto/simd.c

   1 /*
   2  * Shared crypto simd helpers
   3  *
   4  * Copyright (c) 2012 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
   5  * Copyright (c) 2016 Herbert Xu <herbert@gondor.apana.org.au>
   6  *
   7  * Based on aesni-intel_glue.c by:
   8  *  Copyright (C) 2008, Intel Corp.
   9  *    Author: Huang Ying <ying.huang@intel.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  *
  24  */
  25
  26 #include <crypto/cryptd.h>
  27 #include <crypto/internal/simd.h>
  28 #include <crypto/internal/skcipher.h>
  29 #include <linux/kernel.h>
  30 #include <linux/module.h>
  31 #include <linux/preempt.h>
  32 #include <asm/simd.h>
  33
  34 struct simd_skcipher_alg {
  35         const char *ialg_name;
  36         struct skcipher_alg alg;
  37 };
  38
  39 struct simd_skcipher_ctx {
  40         struct cryptd_skcipher *cryptd_tfm;
  41 };
  42
  43 static int simd_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
  44                                 unsigned int key_len)
  45 {
  46         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  47         struct crypto_skcipher *child = &ctx->cryptd_tfm->base;
  48         int err;
  49
  50         crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  51         crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(tfm) &
  52                                          CRYPTO_TFM_REQ_MASK);
  53         err = crypto_skcipher_setkey(child, key, key_len);
  54         crypto_skcipher_set_flags(tfm, crypto_skcipher_get_flags(child) &
  55                                        CRYPTO_TFM_RES_MASK);
  56         return err;
  57 }
  58
  59 static int simd_skcipher_encrypt(struct skcipher_request *req)
  60 {
  61         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  62         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  63         struct skcipher_request *subreq;
  64         struct crypto_skcipher *child;
  65
  66         subreq = skcipher_request_ctx(req);
  67         *subreq = *req;
  68
  69         if (!may_use_simd() ||
  70             (in_atomic() && cryptd_skcipher_queued(ctx->cryptd_tfm)))
  71                 child = &ctx->cryptd_tfm->base;
  72         else
  73                 child = cryptd_skcipher_child(ctx->cryptd_tfm);
  74
  75         skcipher_request_set_tfm(subreq, child);
  76
  77         return crypto_skcipher_encrypt(subreq);
  78 }
  79
  80 static int simd_skcipher_decrypt(struct skcipher_request *req)
  81 {
  82         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  83         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  84         struct skcipher_request *subreq;
  85         struct crypto_skcipher *child;
  86
  87         subreq = skcipher_request_ctx(req);
  88         *subreq = *req;
  89
  90         if (!may_use_simd() ||
  91             (in_atomic() && cryptd_skcipher_queued(ctx->cryptd_tfm)))
  92                 child = &ctx->cryptd_tfm->base;
  93         else
  94                 child = cryptd_skcipher_child(ctx->cryptd_tfm);
  95
  96         skcipher_request_set_tfm(subreq, child);
  97
  98         return crypto_skcipher_decrypt(subreq);
  99 }
 100
 101 static void simd_skcipher_exit(struct crypto_skcipher *tfm)
 102 {
 103         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 104
 105         cryptd_free_skcipher(ctx->cryptd_tfm);
 106 }
 107
 108 static int simd_skcipher_init(struct crypto_skcipher *tfm)
 109 {
 110         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 111         struct cryptd_skcipher *cryptd_tfm;
 112         struct simd_skcipher_alg *salg;
 113         struct skcipher_alg *alg;
 114         unsigned reqsize;
 115
 116         alg = crypto_skcipher_alg(tfm);
 117         salg = container_of(alg, struct simd_skcipher_alg, alg);
 118
 119         cryptd_tfm = cryptd_alloc_skcipher(salg->ialg_name,
 120                                            CRYPTO_ALG_INTERNAL,
 121                                            CRYPTO_ALG_INTERNAL);
 122         if (IS_ERR(cryptd_tfm))
 123                 return PTR_ERR(cryptd_tfm);
 124
 125         ctx->cryptd_tfm = cryptd_tfm;
 126
 127         reqsize = sizeof(struct skcipher_request);
 128         reqsize += crypto_skcipher_reqsize(&cryptd_tfm->base);
 129
 130         crypto_skcipher_set_reqsize(tfm, reqsize);
 131
 132         return 0;
 133 }
 134
 135 struct simd_skcipher_alg *simd_skcipher_create_compat(const char *algname,
 136                                                       const char *drvname,
 137                                                       const char *basename)
 138 {
 139         struct simd_skcipher_alg *salg;
 140         struct crypto_skcipher *tfm;
 141         struct skcipher_alg *ialg;
 142         struct skcipher_alg *alg;
 143         int err;
 144
 145         tfm = crypto_alloc_skcipher(basename, CRYPTO_ALG_INTERNAL,
 146                                     CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
 147         if (IS_ERR(tfm))
 148                 return ERR_CAST(tfm);
 149
 150         ialg = crypto_skcipher_alg(tfm);
 151
 152         salg = kzalloc(sizeof(*salg), GFP_KERNEL);
 153         if (!salg) {
 154                 salg = ERR_PTR(-ENOMEM);
 155                 goto out_put_tfm;
 156         }
 157
 158         salg->ialg_name = basename;
 159         alg = &salg->alg;
 160
 161         err = -ENAMETOOLONG;
 162         if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
 163             CRYPTO_MAX_ALG_NAME)
 164                 goto out_free_salg;
 165
 166         if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 167                      drvname) >= CRYPTO_MAX_ALG_NAME)
 168                 goto out_free_salg;
 169
 170         alg->base.cra_flags = CRYPTO_ALG_ASYNC;
 171         alg->base.cra_priority = ialg->base.cra_priority;
 172         alg->base.cra_blocksize = ialg->base.cra_blocksize;
 173         alg->base.cra_alignmask = ialg->base.cra_alignmask;
 174         alg->base.cra_module = ialg->base.cra_module;
 175         alg->base.cra_ctxsize = sizeof(struct simd_skcipher_ctx);
 176
 177         alg->ivsize = ialg->ivsize;
 178         alg->chunksize = ialg->chunksize;
 179         alg->min_keysize = ialg->min_keysize;
 180         alg->max_keysize = ialg->max_keysize;
 181
 182         alg->init = simd_skcipher_init;
 183         alg->exit = simd_skcipher_exit;
 184
 185         alg->setkey = simd_skcipher_setkey;
 186         alg->encrypt = simd_skcipher_encrypt;
 187         alg->decrypt = simd_skcipher_decrypt;
 188
 189         err = crypto_register_skcipher(alg);
 190         if (err)
 191                 goto out_free_salg;
 192
 193 out_put_tfm:
 194         crypto_free_skcipher(tfm);
 195         return salg;
 196
 197 out_free_salg:
 198         kfree(salg);
 199         salg = ERR_PTR(err);
 200         goto out_put_tfm;
 201 }
 202 EXPORT_SYMBOL_GPL(simd_skcipher_create_compat);
 203
 204 struct simd_skcipher_alg *simd_skcipher_create(const char *algname,
 205                                                const char *basename)
 206 {
 207         char drvname[CRYPTO_MAX_ALG_NAME];
 208
 209         if (snprintf(drvname, CRYPTO_MAX_ALG_NAME, "simd-%s", basename) >=
 210             CRYPTO_MAX_ALG_NAME)
 211                 return ERR_PTR(-ENAMETOOLONG);
 212
 213         return simd_skcipher_create_compat(algname, drvname, basename);
 214 }
 215 EXPORT_SYMBOL_GPL(simd_skcipher_create);
 216
 217 void simd_skcipher_free(struct simd_skcipher_alg *salg)
 218 {
 219         crypto_unregister_skcipher(&salg->alg);
 220         kfree(salg);
 221 }
 222 EXPORT_SYMBOL_GPL(simd_skcipher_free);
 223
 224 MODULE_LICENSE("GPL");