LXR linux/crypto/krng.c

   1/*
   2 * RNG implementation using standard kernel RNG.
   3 *
   4 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
   5 *
   6 * This program is free software; you can redistribute it and/or modify it
   7 * under the terms of the GNU General Public License as published by the
   8 * Free Software Foundation; either version 2 of the License, or (at your
   9 * any later version.
  10 *
  11 */
  12
  13#include <crypto/internal/rng.h>
  14#include <linux/err.h>
  15#include <linux/init.h>
  16#include <linux/module.h>
  17#include <linux/random.h>
  18
  19static int krng_get_random(struct crypto_rng *tfm, u8 *rdata, unsigned int dlen)
  20{
  21        get_random_bytes(rdata, dlen);
  22        return 0;
  23}
  24
  25static int krng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
  26{
  27        return 0;
  28}
  29
  30static struct crypto_alg krng_alg = {
  31        .cra_name               = "stdrng",
  32        .cra_driver_name        = "krng",
  33        .cra_priority           = 200,
  34        .cra_flags              = CRYPTO_ALG_TYPE_RNG,
  35        .cra_ctxsize            = 0,
  36        .cra_type               = &crypto_rng_type,
  37        .cra_module             = THIS_MODULE,
  38        .cra_list               = LIST_HEAD_INIT(krng_alg.cra_list),
  39        .cra_u                  = {
  40                .rng = {
  41                        .rng_make_random        = krng_get_random,
  42                        .rng_reset              = krng_reset,
  43                        .seedsize               = 0,
  44                }
  45        }
  46};
  47
  48
  49/* Module initalization */
  50static int __init krng_mod_init(void)
  51{
  52        return crypto_register_alg(&krng_alg);
  53}
  54
  55static void __exit krng_mod_fini(void)
  56{
  57        crypto_unregister_alg(&krng_alg);
  58        return;
  59}
  60
  61module_init(krng_mod_init);
  62module_exit(krng_mod_fini);
  63
  64MODULE_LICENSE("GPL");
  65MODULE_DESCRIPTION("Kernel Random Number Generator");
  66MODULE_ALIAS("stdrng");
  67