ecdsa.h

Go to the documentation of this file.

/*
 *  Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  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.
 *
 *  This file is part of Mbed TLS (https://tls.mbed.org)
 */

#ifndef MBEDTLS_ECDSA_H
#define MBEDTLS_ECDSA_H

#include "ecp.h"
#include "md.h"

/*
 * RFC-4492 page 20:
 *
 *     Ecdsa-Sig-Value ::= SEQUENCE {
 *         r       INTEGER,
 *         s       INTEGER
 *     }
 *
 * Size is at most
 *    1 (tag) + 1 (len) + 1 (initial 0) + ECP_MAX_BYTES for each of r and s,
 *    twice that + 1 (tag) + 2 (len) for the sequence
 * (assuming ECP_MAX_BYTES is less than 126 for r and s,
 * and less than 124 (total len <= 255) for the sequence)
 */
#if MBEDTLS_ECP_MAX_BYTES > 124
#error "MBEDTLS_ECP_MAX_BYTES bigger than expected, please fix MBEDTLS_ECDSA_MAX_LEN"
#endif

#define MBEDTLS_ECDSA_MAX_LEN  ( 3 + 2 * ( 3 + MBEDTLS_ECP_MAX_BYTES ) )

#ifdef __cplusplus
extern "C" {
#endif

typedef mbedtls_ecp_keypair mbedtls_ecdsa_context;

#if defined(MBEDTLS_ECP_RESTARTABLE)

typedef struct mbedtls_ecdsa_restart_ver mbedtls_ecdsa_restart_ver_ctx;

typedef struct mbedtls_ecdsa_restart_sig mbedtls_ecdsa_restart_sig_ctx;

#if defined(MBEDTLS_ECDSA_DETERMINISTIC)

typedef struct mbedtls_ecdsa_restart_det mbedtls_ecdsa_restart_det_ctx;
#endif

typedef struct
{
    mbedtls_ecp_restart_ctx ecp;        
    mbedtls_ecdsa_restart_ver_ctx *ver; 
    mbedtls_ecdsa_restart_sig_ctx *sig; 
#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
    mbedtls_ecdsa_restart_det_ctx *det; 
#endif
} mbedtls_ecdsa_restart_ctx;

#else /* MBEDTLS_ECP_RESTARTABLE */

/* Now we can declare functions that take a pointer to that */
typedef void mbedtls_ecdsa_restart_ctx;

#endif /* MBEDTLS_ECP_RESTARTABLE */

int mbedtls_ecdsa_sign( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s,
                const mbedtls_mpi *d, const unsigned char *buf, size_t blen,
                int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );

#if defined(MBEDTLS_ECDSA_DETERMINISTIC)

int mbedtls_ecdsa_sign_det( mbedtls_ecp_group *grp, mbedtls_mpi *r,
                            mbedtls_mpi *s, const mbedtls_mpi *d,
                            const unsigned char *buf, size_t blen,
                            mbedtls_md_type_t md_alg );
#endif /* MBEDTLS_ECDSA_DETERMINISTIC */

int mbedtls_ecdsa_verify( mbedtls_ecp_group *grp,
                          const unsigned char *buf, size_t blen,
                          const mbedtls_ecp_point *Q, const mbedtls_mpi *r,
                          const mbedtls_mpi *s);

int mbedtls_ecdsa_write_signature( mbedtls_ecdsa_context *ctx,
                                   mbedtls_md_type_t md_alg,
                           const unsigned char *hash, size_t hlen,
                           unsigned char *sig, size_t *slen,
                           int (*f_rng)(void *, unsigned char *, size_t),
                           void *p_rng );

int mbedtls_ecdsa_write_signature_restartable( mbedtls_ecdsa_context *ctx,
                           mbedtls_md_type_t md_alg,
                           const unsigned char *hash, size_t hlen,
                           unsigned char *sig, size_t *slen,
                           int (*f_rng)(void *, unsigned char *, size_t),
                           void *p_rng,
                           mbedtls_ecdsa_restart_ctx *rs_ctx );

#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
#if ! defined(MBEDTLS_DEPRECATED_REMOVED)
#if defined(MBEDTLS_DEPRECATED_WARNING)
#define MBEDTLS_DEPRECATED    __attribute__((deprecated))
#else
#define MBEDTLS_DEPRECATED
#endif

int mbedtls_ecdsa_write_signature_det( mbedtls_ecdsa_context *ctx,
                               const unsigned char *hash, size_t hlen,
                               unsigned char *sig, size_t *slen,
                               mbedtls_md_type_t md_alg ) MBEDTLS_DEPRECATED;
#undef MBEDTLS_DEPRECATED
#endif /* MBEDTLS_DEPRECATED_REMOVED */
#endif /* MBEDTLS_ECDSA_DETERMINISTIC */

int mbedtls_ecdsa_read_signature( mbedtls_ecdsa_context *ctx,
                          const unsigned char *hash, size_t hlen,
                          const unsigned char *sig, size_t slen );

int mbedtls_ecdsa_read_signature_restartable( mbedtls_ecdsa_context *ctx,
                          const unsigned char *hash, size_t hlen,
                          const unsigned char *sig, size_t slen,
                          mbedtls_ecdsa_restart_ctx *rs_ctx );

int mbedtls_ecdsa_genkey( mbedtls_ecdsa_context *ctx, mbedtls_ecp_group_id gid,
                  int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );

int mbedtls_ecdsa_from_keypair( mbedtls_ecdsa_context *ctx,
                                const mbedtls_ecp_keypair *key );

void mbedtls_ecdsa_init( mbedtls_ecdsa_context *ctx );

void mbedtls_ecdsa_free( mbedtls_ecdsa_context *ctx );

#if defined(MBEDTLS_ECP_RESTARTABLE)

void mbedtls_ecdsa_restart_init( mbedtls_ecdsa_restart_ctx *ctx );

void mbedtls_ecdsa_restart_free( mbedtls_ecdsa_restart_ctx *ctx );
#endif /* MBEDTLS_ECP_RESTARTABLE */

#ifdef __cplusplus
}
#endif

#endif /* ecdsa.h */