/* crypto/ecdsa/ecdsa.h */
/**
 * \file   crypto/ecdsa/ecdsa.h Include file for the OpenSSL ECDSA functions
 * \author Written by Nils Larsch for the OpenSSL project
 */
/* ====================================================================
 * Copyright (c) 2000-2003 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */
#ifndef HEADER_ECDSA_H
#define HEADER_ECDSA_H

#include <openssl/opensslconf.h>

#ifdef OPENSSL_NO_ECDSA
#error ECDSA is disabled.
#endif

#include <openssl/ec.h>
#include <openssl/ossl_typ.h>
#ifndef OPENSSL_NO_DEPRECATED
#include <openssl/bn.h>
#endif

#ifdef __cplusplus
extern "C" {
#endif

/* Already defined in ossl_typ.h */
/* typedef struct ecdsa_method ECDSA_METHOD; */

typedef struct ECDSA_SIG_st
	{
	BIGNUM *r;
	BIGNUM *s;
	} ECDSA_SIG;

struct ecdsa_method 
	{
	const char *name;
	ECDSA_SIG *(*ecdsa_do_sign)(const unsigned char *dgst, int dgst_len, 
			EC_KEY *eckey);
	int (*ecdsa_sign_setup)(EC_KEY *eckey, BN_CTX *ctx, BIGNUM **kinv, 
			BIGNUM **r);
	int (*ecdsa_do_verify)(const unsigned char *dgst, int dgst_len, 
			ECDSA_SIG *sig, EC_KEY *eckey);
#if 0
	int (*init)(EC_KEY *eckey);
	int (*finish)(EC_KEY *eckey);
#endif
	int flags;
	char *app_data;
	};

typedef struct ecdsa_data_st {
	/* EC_KEY_METH_DATA part */
	int (*init)(EC_KEY *);
	void (*finish)(EC_KEY *);
	/* method (ECDSA) specific part */
	BIGNUM	*kinv;	/* signing pre-calc */
	BIGNUM	*r;	/* signing pre-calc */
	ENGINE	*engine;
	int	flags;
	const ECDSA_METHOD *meth;
	CRYPTO_EX_DATA ex_data;
} ECDSA_DATA; 

/** ECDSA_SIG *ECDSA_SIG_new(void)
 * allocates and initialize a ECDSA_SIG structure
 * \return pointer to a ECDSA_SIG structure or NULL if an error occurred
 */
ECDSA_SIG *ECDSA_SIG_new(void);

/** ECDSA_SIG_free
 * frees a ECDSA_SIG structure
 * \param a pointer to the ECDSA_SIG structure
 */
void	  ECDSA_SIG_free(ECDSA_SIG *a);

/** i2d_ECDSA_SIG
 * DER encode content of ECDSA_SIG object (note: this function modifies *pp
 * (*pp += length of the DER encoded signature)).
 * \param a  pointer to the ECDSA_SIG object
 * \param pp pointer to a unsigned char pointer for the output or NULL
 * \return the length of the DER encoded ECDSA_SIG object or 0 
 */
int	  i2d_ECDSA_SIG(const ECDSA_SIG *a, unsigned char **pp);

/** d2i_ECDSA_SIG
 * decodes a DER encoded ECDSA signature (note: this function changes *pp
 * (*pp += len)). 
 * \param v pointer to ECDSA_SIG pointer (may be NULL)
 * \param pp buffer with the DER encoded signature
 * \param len bufferlength
 * \return pointer to the decoded ECDSA_SIG structure (or NULL)
 */
ECDSA_SIG *d2i_ECDSA_SIG(ECDSA_SIG **v, const unsigned char **pp, long len);

/** ECDSA_DATA_new
 * creates a new ECDSA_DATA object
 * \return pointer to a newly allocated (and initialized) ECDSA_DATA object
 */
ECDSA_DATA *ECDSA_DATA_new(void);

/** ECDSA_DATA_new_method
 * creates a new ECDSA_DATA object using a specified ENGINE
 * \param eng pointer to a ENGINE structure
 * \return pointer to a newly allocated (and initialized) ECDSA_DATA object
 */
ECDSA_DATA *ECDSA_DATA_new_method(ENGINE *eng);

/** ECDSA_DATA_free
 * frees ECDSA_DATA structure
 * \param data pointer to a ECDSA_DATA structure
 */
void ECDSA_DATA_free(ECDSA_DATA *data);

/** ecdsa_check
 * checks whether ECKEY->meth_data is a pointer to a ECDSA_DATA structure
 * and if not it removes the old meth_data and creates a ECDSA_DATA structure.
 * \param  eckey pointer to a EC_KEY object
 * \return pointer to a ECDSA_DATA structure
 */
ECDSA_DATA *ecdsa_check(EC_KEY *eckey);

/** ECDSA_do_sign
 * computes the ECDSA signature of the given hash value using
 * the supplied private key and returns the created signature.
 * \param dgst pointer to the hash value
 * \param dgst_len length of the hash value
 * \param eckey pointer to the EC_KEY object containing a private EC key
 * \return pointer to a ECDSA_SIG structure or NULL
 */
ECDSA_SIG *ECDSA_do_sign(const unsigned char *dgst,int dgst_len,EC_KEY *eckey);

/** ECDSA_do_verify
 * verifies that the supplied signature is a valid ECDSA
 * signature of the supplied hash value using the supplied public key.
 * \param dgst pointer to the hash value
 * \param dgst_len length of the hash value
 * \param sig  pointer to the ECDSA_SIG structure
 * \param eckey pointer to the EC_KEY object containing a public EC key
 * \return 1 if the signature is valid, 0 if the signature is invalid and -1 on error
 */
int	  ECDSA_do_verify(const unsigned char *dgst, int dgst_len, ECDSA_SIG 
		*sig, EC_KEY* eckey);

const ECDSA_METHOD *ECDSA_OpenSSL(void);

/** ECDSA_set_default_method
 * sets the default ECDSA method
 * \param meth the new default ECDSA_METHOD
 */
void	  ECDSA_set_default_method(const ECDSA_METHOD *meth);

/** ECDSA_get_default_method
 * returns the default ECDSA method
 * \return pointer to ECDSA_METHOD structure containing the default method
 */
const ECDSA_METHOD *ECDSA_get_default_method(void);

/** ECDSA_set_method
 * sets method to be used for the ECDSA operations
 * \param eckey pointer to the EC_KEY object
 * \param meth  pointer to the new method
 * \return 1 on success and 0 otherwise 
 */
int 	  ECDSA_set_method(EC_KEY *eckey, const ECDSA_METHOD *meth);

/** ECDSA_size
 * returns the maximum length of the DER encoded signature
 * \param  eckey pointer to a EC_KEY object
 * \return numbers of bytes required for the DER encoded signature
 */
int	  ECDSA_size(const EC_KEY *eckey);

/** ECDSA_sign_setup
 * precompute parts of the signing operation (the computed values may be
 * passed to ECDSA_DATA->kinv and ECDSA_DATA->r for a later signature
 * computation).
 * \param eckey pointer to the EC_KEY object containing a private EC key
 * \param ctx  pointer to a BN_CTX object (may be NULL)
 * \param kinv pointer to a BIGNUM pointer for the inverse of k
 * \param rp   pointer to a BIGNUM pointer for x coordinate of k * generator
 * \return 1 on success and 0 otherwise
 */
int 	  ECDSA_sign_setup(EC_KEY *eckey, BN_CTX *ctx, BIGNUM **kinv, 
		BIGNUM **rp);

/** ECDSA_sign
 * computes ECDSA signature of a given hash value using the supplied
 * private key (note: sig must point to ECDSA_size(eckey) bytes of memory).
 * \param type this parameter is ignored
 * \param dgst pointer to the hash value to sign
 * \param dgstlen length of the hash value
 * \param sig buffer to hold the DER encoded signature
 * \param siglen pointer to the length of the returned signature
 * \param eckey pointer to the EC_KEY object containing a private EC key
 * \return 1 on success and 0 otherwise
 */
int	  ECDSA_sign(int type, const unsigned char *dgst, int dgstlen, 
		unsigned char *sig, unsigned int *siglen, EC_KEY *eckey);

/** ECDSA_verify
 * verifies that the given signature is valid ECDSA signature
 * of the supplied hash value using the specified public key.
 * \param type this parameter is ignored
 * \param dgst pointer to the hash value 
 * \param dgstlen length of the hash value
 * \param sig  pointer to the DER encoded signature
 * \param siglen length of the DER encoded signature
 * \param eckey pointer to the EC_KEY object containing a public EC key
 * \return 1 if the signature is valid, 0 if the signature is invalid and -1 on error
 */
int 	  ECDSA_verify(int type, const unsigned char *dgst, int dgstlen, 
		const unsigned char *sig, int siglen, EC_KEY *eckey);

/* the standard ex_data functions */
int 	  ECDSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new 
		*new_func, CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
int 	  ECDSA_set_ex_data(EC_KEY *d, int idx, void *arg);
void 	  *ECDSA_get_ex_data(EC_KEY *d, int idx);


/* BEGIN ERROR CODES */
/* The following lines are auto generated by the script mkerr.pl. Any changes
 * made after this point may be overwritten when the script is next run.
 */
void ERR_load_ECDSA_strings(void);

/* Error codes for the ECDSA functions. */

/* Function codes. */
#define ECDSA_F_ECDSA_DATA_NEW				 100
#define ECDSA_F_ECDSA_DO_SIGN				 101
#define ECDSA_F_ECDSA_DO_VERIFY				 102
#define ECDSA_F_ECDSA_SIGN_SETUP			 103

/* Reason codes. */
#define ECDSA_R_BAD_SIGNATURE				 100
#define ECDSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE		 101
#define ECDSA_R_ERR_EC_LIB				 102
#define ECDSA_R_MISSING_PARAMETERS			 103
#define ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED		 104
#define ECDSA_R_SIGNATURE_MALLOC_FAILED			 105

#ifdef  __cplusplus
}
#endif
#endif