50 lines
		
	
	
	
		
			1.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			50 lines
		
	
	
	
		
			1.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
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								/* Signature verification with an asymmetric key
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								 *
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								 * See Documentation/security/asymmetric-keys.txt
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								 *
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								 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
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								 * Written by David Howells (dhowells@redhat.com)
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								 *
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								 * This program is free software; you can redistribute it and/or
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								 * modify it under the terms of the GNU General Public Licence
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								 * as published by the Free Software Foundation; either version
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								 * 2 of the Licence, or (at your option) any later version.
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								 */
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								#include <keys/asymmetric-subtype.h>
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								#include <linux/module.h>
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								#include <linux/err.h>
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								#include <crypto/public_key.h>
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								#include "asymmetric_keys.h"
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								/**
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								 * verify_signature - Initiate the use of an asymmetric key to verify a signature
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								 * @key: The asymmetric key to verify against
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								 * @sig: The signature to check
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								 *
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								 * Returns 0 if successful or else an error.
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								 */
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								int verify_signature(const struct key *key,
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										     const struct public_key_signature *sig)
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								{
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									const struct asymmetric_key_subtype *subtype;
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									int ret;
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									pr_devel("==>%s()\n", __func__);
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									if (key->type != &key_type_asymmetric)
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										return -EINVAL;
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									subtype = asymmetric_key_subtype(key);
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									if (!subtype ||
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									    !key->payload.data)
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										return -EINVAL;
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									if (!subtype->verify_signature)
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										return -ENOTSUPP;
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									ret = subtype->verify_signature(key, sig);
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									pr_devel("<==%s() = %d\n", __func__, ret);
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									return ret;
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								}
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								EXPORT_SYMBOL_GPL(verify_signature);
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