This patch adds a random number generator interface as well as a cryptographic pseudo-random number generator based on AES. It is meant to be used in cases where a deterministic CPRNG is required. One of the first applications will be as an input in the IPsec IV generation process. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
		
			
				
	
	
		
			66 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * RNG implementation using standard kernel RNG.
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 *
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 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
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 *
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 * This program is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License as published by the
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 * Free Software Foundation; either version 2 of the License, or (at your
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 * any later version.
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 *
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 */
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#include <crypto/internal/rng.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/random.h>
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static int krng_get_random(struct crypto_rng *tfm, u8 *rdata, unsigned int dlen)
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{
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	get_random_bytes(rdata, dlen);
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	return 0;
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}
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static int krng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen)
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{
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	return 0;
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}
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static struct crypto_alg krng_alg = {
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	.cra_name		= "stdrng",
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	.cra_driver_name	= "krng",
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	.cra_priority		= 200,
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	.cra_flags		= CRYPTO_ALG_TYPE_RNG,
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	.cra_ctxsize		= 0,
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	.cra_type		= &crypto_rng_type,
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	.cra_module		= THIS_MODULE,
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	.cra_list		= LIST_HEAD_INIT(krng_alg.cra_list),
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	.cra_u			= {
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		.rng = {
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			.rng_make_random	= krng_get_random,
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			.rng_reset		= krng_reset,
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			.seedsize		= 0,
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		}
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	}
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};
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/* Module initalization */
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static int __init krng_mod_init(void)
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{
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	return crypto_register_alg(&krng_alg);
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}
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static void __exit krng_mod_fini(void)
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{
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	crypto_unregister_alg(&krng_alg);
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	return;
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}
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module_init(krng_mod_init);
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module_exit(krng_mod_fini);
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MODULE_LICENSE("GPL");
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MODULE_DESCRIPTION("Kernel Random Number Generator");
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MODULE_ALIAS("stdrng");
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