linux/include/crypto/ecdh.h
Stefan Berger 288b46c57c crypto: ecc - Add NIST P521 curve parameters
Add the parameters for the NIST P521 curve and define a new curve ID
for it. Make the curve available in ecc_get_curve.

Tested-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2024-04-12 15:07:52 +08:00

84 lines
2.5 KiB
C

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