crypto/ablkcipher.c

   1 /*
   2  * Asynchronous block chaining cipher operations.
   3  *
   4  * This is the asynchronous version of blkcipher.c indicating completion
   5  * via a callback.
   6  *
   7  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by the Free
  11  * Software Foundation; either version 2 of the License, or (at your option)
  12  * any later version.
  13  *
  14  */
  15
  16 #include <crypto/algapi.h>
  17 #include <linux/errno.h>
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/seq_file.h>
  21
  22 static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key, unsigned int keylen)
  23 {
  24         struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
  25         unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
  26         int ret;
  27         u8 *buffer, *alignbuffer;
  28         unsigned long absize;
  29
  30         absize = keylen + alignmask;
  31         buffer = kmalloc(absize, GFP_ATOMIC);
  32         if (!buffer)
  33                 return -ENOMEM;
  34
  35         alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
  36         memcpy(alignbuffer, key, keylen);
  37         ret = cipher->setkey(tfm, alignbuffer, keylen);
  38         memset(alignbuffer, 0, keylen);
  39         kfree(buffer);
  40         return ret;
  41 }
  42
  43 static int setkey(struct crypto_ablkcipher *tfm, const u8 *key,
  44                   unsigned int keylen)
  45 {
  46         struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
  47         unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
  48
  49         if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
  50                 crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
  51                 return -EINVAL;
  52         }
  53
  54         if ((unsigned long)key & alignmask)
  55                 return setkey_unaligned(tfm, key, keylen);
  56
  57         return cipher->setkey(tfm, key, keylen);
  58 }
  59
  60 static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
  61                                               u32 mask)
  62 {
  63         return alg->cra_ctxsize;
  64 }
  65
  66 static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
  67                                       u32 mask)
  68 {
  69         struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
  70         struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
  71
  72         if (alg->ivsize > PAGE_SIZE / 8)
  73                 return -EINVAL;
  74
  75         crt->setkey = setkey;
  76         crt->encrypt = alg->encrypt;
  77         crt->decrypt = alg->decrypt;
  78         crt->ivsize = alg->ivsize;
  79
  80         return 0;
  81 }
  82
  83 static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
  84         __attribute__ ((unused));
  85 static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
  86 {
  87         struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
  88
  89         seq_printf(m, "type         : ablkcipher\n");
  90         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
  91         seq_printf(m, "min keysize  : %u\n", ablkcipher->min_keysize);
  92         seq_printf(m, "max keysize  : %u\n", ablkcipher->max_keysize);
  93         seq_printf(m, "ivsize       : %u\n", ablkcipher->ivsize);
  94         if (ablkcipher->queue) {
  95                 seq_printf(m, "qlen         : %u\n", ablkcipher->queue->qlen);
  96                 seq_printf(m, "max qlen     : %u\n", ablkcipher->queue->max_qlen);
  97         }
  98 }
  99
 100 const struct crypto_type crypto_ablkcipher_type = {
 101         .ctxsize = crypto_ablkcipher_ctxsize,
 102         .init = crypto_init_ablkcipher_ops,
 103 #ifdef CONFIG_PROC_FS
 104         .show = crypto_ablkcipher_show,
 105 #endif
 106 };
 107 EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
 108
 109 MODULE_LICENSE("GPL");
 110 MODULE_DESCRIPTION("Asynchronous block chaining cipher type");