84 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			84 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0-or-later */
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| /*
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|  * ECDH params to be used with kpp API
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|  *
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|  * Copyright (c) 2016, Intel Corporation
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|  * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
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|  */
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| #ifndef _CRYPTO_ECDH_
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| #define _CRYPTO_ECDH_
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| 
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| /**
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|  * DOC: ECDH Helper Functions
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|  *
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|  * To use ECDH with the KPP cipher API, the following data structure and
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|  * functions should be used.
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|  *
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|  * The ECC curves known to the ECDH implementation are specified in this
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|  * header file.
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|  *
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|  * To use ECDH with KPP, the following functions should be used to operate on
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|  * an ECDH private key. The packet private key that can be set with
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|  * the KPP API function call of crypto_kpp_set_secret.
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|  */
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| 
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| /* Curves IDs */
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| #define ECC_CURVE_NIST_P192	0x0001
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| #define ECC_CURVE_NIST_P256	0x0002
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| #define ECC_CURVE_NIST_P384	0x0003
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| #define ECC_CURVE_NIST_P521	0x0004
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| 
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| /**
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|  * struct ecdh - define an ECDH private key
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|  *
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|  * @key:	Private ECDH key
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|  * @key_size:	Size of the private ECDH key
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|  */
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| struct ecdh {
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| 	char *key;
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| 	unsigned short key_size;
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| };
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| 
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| /**
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|  * crypto_ecdh_key_len() - Obtain the size of the private ECDH key
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|  * @params:	private ECDH key
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|  *
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|  * This function returns the packet ECDH key size. A caller can use that
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|  * with the provided ECDH private key reference to obtain the required
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|  * memory size to hold a packet key.
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|  *
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|  * Return: size of the key in bytes
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|  */
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| unsigned int crypto_ecdh_key_len(const struct ecdh *params);
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| 
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| /**
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|  * crypto_ecdh_encode_key() - encode the private key
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|  * @buf:	Buffer allocated by the caller to hold the packet ECDH
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|  *		private key. The buffer should be at least crypto_ecdh_key_len
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|  *		bytes in size.
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|  * @len:	Length of the packet private key buffer
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|  * @p:		Buffer with the caller-specified private key
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|  *
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|  * The ECDH implementations operate on a packet representation of the private
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|  * key.
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|  *
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|  * Return:	-EINVAL if buffer has insufficient size, 0 on success
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|  */
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| int crypto_ecdh_encode_key(char *buf, unsigned int len, const struct ecdh *p);
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| 
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| /**
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|  * crypto_ecdh_decode_key() - decode a private key
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|  * @buf:	Buffer holding a packet key that should be decoded
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|  * @len:	Length of the packet private key buffer
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|  * @p:		Buffer allocated by the caller that is filled with the
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|  *		unpacked ECDH private key.
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|  *
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|  * The unpacking obtains the private key by pointing @p to the correct location
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|  * in @buf. Thus, both pointers refer to the same memory.
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|  *
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|  * Return:	-EINVAL if buffer has insufficient size, 0 on success
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|  */
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| int crypto_ecdh_decode_key(const char *buf, unsigned int len, struct ecdh *p);
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| 
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| #endif
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