/*******************************************************************************
* Ledger Nano S - Secure firmware
* (c) 2022 Ledger
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
********************************************************************************/
/**
* @file lcx_eddsa.h
* @brief EDDSA (Edwards Curve Digital Signature Algorithm)
*
* EDDSA is a digital signature scheme relying on Edwards curves, especially
* Ed25519 and Ed448. Refer to RFC8032
* for more details.
*/
#ifdef HAVE_EDDSA
#include "lcx_ecfp.h"
#include "lcx_wrappers.h"
#ifndef LCX_EDDSA_H
#define LCX_EDDSA_H
/**
* @brief Signs a message digest.
*
* @details The signature is done according to the EDDSA specification
* RFC8032 .
*
* @param[in] pvkey Private key.
* This shall be initialized with #cx_ecfp_init_private_key_no_throw.
*
* @param[in] hashID Message digest agorithm identifier.
* Algorithms supported:
* - SHA512
* - SHA3
* - Keccak
*
* @param[in] hash Pointer to the message digest.
*
* @param[in] hash_len Length of the digest.
*
* @param[out] sig Buffer where to store the signature.
*
* @param[in] sig_len Length of the signature.
*
* @return Error code:
* - CX_OK on success
* - CX_EC_INVALID_CURVE
* - CX_INVALID_PARAMETER
* - INVALID_PARAMETER
* - CX_NOT_UNLOCKED
* - CX_INVALID_PARAMETER_SIZE
* - CX_MEMORY_FULL
* - CX_NOT_LOCKED
* - CX_INVALID_PARAMETER_SIZE
* - CX_EC_INVALID_POINT
* - CX_EC_INFINITE_POINT
* - CX_INTERNAL_ERROR
* - CX_INVALID_PARAMETER_VALUE
*/
cx_err_t cx_eddsa_sign_no_throw(const cx_ecfp_private_key_t *pvkey,
cx_md_t hashID,
const uint8_t * hash,
size_t hash_len,
uint8_t * sig,
size_t sig_len);
/**
* @brief Signs a message digest.
*
* @details The signature is done according to the EDDSA specification
* RFC8032 .
* This function throws an exception if the computation doesn't
* succeed.
*
* @warning It is recommended to use #cx_eddsa_sign_no_throw rather than
* this function.
*
* @param[in] pvkey Private key.
* This shall be initialized with #cx_ecfp_init_private_key_no_throw.
*
* @param[in] mode Mode. This parameter is not used.
*
* @param[in] hashID Message digest agorithm identifier.
* Algorithms supported:
* - SHA512
* - SHA3
* - Keccak
*
* @param[in] hash Pointer to the message digest.
*
* @param[in] hash_len Length of the digest.
*
* @param[in] ctx Pointer to the context. This parameter is not used.
*
* @param[in] ctx_len Length of *ctx*. This parameter is not used.
*
* @param[out] sig Buffer where to store the signature.
*
* @param[in] sig_len Length of the signature.
*
* @param[in] info Additional information. This parameter is not used.
*
* @return Length of the signature.
*
* @throws CX_EC_INVALID_CURVE
* @throws CX_INVALID_PARAMETER
* @throws INVALID_PARAMETER
* @throws CX_NOT_UNLOCKED
* @throws CX_INVALID_PARAMETER_SIZE
* @throws CX_MEMORY_FULL
* @throws CX_NOT_LOCKED
* @throws CX_INVALID_PARAMETER_SIZE
* @throws CX_EC_INVALID_POINT
* @throws CX_EC_INFINITE_POINT
* @throws CX_INTERNAL_ERROR
* @throws CX_INVALID_PARAMETER_VALUE
*/
static inline size_t cx_eddsa_sign ( const cx_ecfp_private_key_t * pvkey, int mode, cx_md_t hashID, const unsigned char * hash, unsigned int hash_len, const unsigned char * ctx, unsigned int ctx_len, unsigned char * sig, unsigned int sig_len, unsigned int * info )
{
UNUSED(ctx);
UNUSED(ctx_len);
UNUSED(mode);
UNUSED(info);
CX_THROW(cx_eddsa_sign_no_throw(pvkey, hashID, hash, hash_len, sig, sig_len));
size_t size;
CX_THROW(cx_ecdomain_parameters_length(pvkey->curve, &size));
return 2 * size;
}
/**
* @brief Verifies a signature.
*
* @details The verification is done according to the specification
* RFC8032 .
*
* @param[in] pukey Public key.
* This shall be initialized with #cx_ecfp_init_public_key_no_throw.
*
* @param[in] hashID Message digest agorithm identifier.
* Algorithms supported:
* - SHA512
* - SHA3
* - Keccak
*
* @param[in] hash Pointer to the message digest.
*
* @param[in] hash_len Length of the digest.
*
* @param[out] sig Pointer to the signature.
*
* @param[in] sig_len Length of the signature.
*
* @return 1 if the signature is verified, otherwise 0.
*/
bool cx_eddsa_verify_no_throw(const cx_ecfp_public_key_t *pukey,
cx_md_t hashID,
const uint8_t * hash,
size_t hash_len,
const uint8_t * sig,
size_t sig_len);
/**
* @brief Verifies a signature.
*
* @details The verification is done according to the specification
* RFC8032 .
* This function throws an exception if the computation doesn't
* succeed.
*
* @param[in] pukey Public key.
* THis shall be initialized with #cx_ecfp_init_public_key_no_throw.
*
* @param[in] mode Mode. This parameter is not used.
*
* @param[in] hashID Message digest agorithm identifier.
* Algorithms supported:
* - SHA512
* - SHA3
* - Keccak
*
* @param[in] hash Pointer to the message digest.
*
* @param[in] hash_len Length of the digest.
*
* @param[in] ctx Pointer to the context. This parameter is not used.
*
* @param[in] ctx_len Length of the context. This parameter is not used.
*
* @param[out] sig Pointer to the signature.
*
* @param[in] sig_len Length of the signature.
*
* @return 1 if the signature is verified, otherwise 0.
*/
static inline int cx_eddsa_verify ( const cx_ecfp_public_key_t * pukey, int mode, cx_md_t hashID, const unsigned char * hash, unsigned int hash_len, const unsigned char * ctx, unsigned int ctx_len, const unsigned char * sig, unsigned int sig_len )
{
UNUSED(mode);
UNUSED(ctx);
UNUSED(ctx_len);
return cx_eddsa_verify_no_throw(pukey, hashID, hash, hash_len, sig, sig_len);
}
/**
* @brief Encodes the curve point coordinates.
*
* @param[in, out] coord A pointer to the point coordinates in the form x|y.
*
* @param[in] len Length of the coordinates.
*
* @param[in] sign Sign of the x-coordinate.
*
*/
void cx_encode_coord(uint8_t * coord,
int len,
int sign);
/**
* @brief Decodes the curve point coordinates.
*
* @param[in, out] coord A pointer to the point encoded coordinates.
*
* @param[in] len Length of the encoded coordinates.
*
* @return Sign of the x-coordinate.
*/
int cx_decode_coord(uint8_t * coord,
int len);
#endif
#endif // HAVE_EDDSA