Functions
ECDSA_SIG *	ECDSA_SIG_new (void)

void	ECDSA_SIG_free (ECDSA_SIG *sig)

int	i2d_ECDSA_SIG (const ECDSA_SIG sig, unsigned char *pp)

ECDSA_SIG *	d2i_ECDSA_SIG (ECDSA_SIG sig, const unsigned char pp, long len)

ECDSA_SIG *	ECDSA_do_sign (const unsigned char dgst, int dgst_len, EC_KEY eckey)

ECDSA_SIG *	ECDSA_do_sign_ex (const unsigned char dgst, int dgstlen, const BIGNUM kinv, const BIGNUM rp, EC_KEY eckey)

int	ECDSA_do_verify (const unsigned char dgst, int dgst_len, const ECDSA_SIG sig, EC_KEY *eckey)

void	ECDSA_set_default_method (const ECDSA_METHOD *meth)

const ECDSA_METHOD *	ECDSA_get_default_method (void)

int	ECDSA_set_method (EC_KEY eckey, const ECDSA_METHOD meth)

int	ECDSA_size (const EC_KEY *eckey)

int	ECDSA_sign_setup (EC_KEY eckey, BN_CTX ctx, BIGNUM kinv, BIGNUM rp)

int	ECDSA_sign (int type, const unsigned char dgst, int dgstlen, unsigned char sig, unsigned int siglen, EC_KEY eckey)

int	ECDSA_sign_ex (int type, const unsigned char dgst, int dgstlen, unsigned char sig, unsigned int siglen, const BIGNUM kinv, const BIGNUM rp, EC_KEY eckey)

int	ECDSA_verify (int type, const unsigned char dgst, int dgstlen, const unsigned char sig, int siglen, EC_KEY *eckey)

Detailed Description

Include file for the OpenSSL ECDSA functions

Author: Written by Nils Larsch for the OpenSSL project

Function Documentation

ECDSA_SIG* d2i_ECDSA_SIG	(	ECDSA_SIG **	sig,
		const unsigned char **	pp,
		long	len
	)

Decodes a DER encoded ECDSA signature (note: this function changes *pp (*pp += len)).

Parameters

sig	pointer to ECDSA_SIG pointer (may be NULL)
pp	memory buffer with the DER encoded signature
len	length of the buffer

Returns: pointer to the decoded ECDSA_SIG structure (or NULL)

ECDSA_SIG* ECDSA_do_sign	(	const unsigned char *	dgst,
		int	dgst_len,
		EC_KEY *	eckey
	)

Computes the ECDSA signature of the given hash value using the supplied private key and returns the created signature.

Parameters

dgst	pointer to the hash value
dgst_len	length of the hash value
eckey	EC_KEY object containing a private EC key

Returns: pointer to a ECDSA_SIG structure or NULL if an error occurred

ECDSA_SIG* ECDSA_do_sign_ex	(	const unsigned char *	dgst,
		int	dgstlen,
		const BIGNUM *	kinv,
		const BIGNUM *	rp,
		EC_KEY *	eckey
	)

Computes ECDSA signature of a given hash value using the supplied private key (note: sig must point to ECDSA_size(eckey) bytes of memory).

Parameters

dgst	pointer to the hash value to sign
dgstlen	length of the hash value
kinv	BIGNUM with a pre-computed inverse k (optional)
rp	BIGNUM with a pre-computed rp value (optioanl), see ECDSA_sign_setup
eckey	EC_KEY object containing a private EC key

Returns: pointer to a ECDSA_SIG structure or NULL if an error occurred

int ECDSA_do_verify	(	const unsigned char *	dgst,
		int	dgst_len,
		const ECDSA_SIG *	sig,
		EC_KEY *	eckey
	)

Verifies that the supplied signature is a valid ECDSA signature of the supplied hash value using the supplied public key.

Parameters

dgst	pointer to the hash value
dgst_len	length of the hash value
sig	ECDSA_SIG structure
eckey	EC_KEY object containing a public EC key

Returns: 1 if the signature is valid, 0 if the signature is invalid and -1 on error

const ECDSA_METHOD* ECDSA_get_default_method ( void )

Returns the default ECDSA method

Returns: pointer to ECDSA_METHOD structure containing the default method

void ECDSA_set_default_method ( const ECDSA_METHOD * meth )

Sets the default ECDSA method

Parameters

meth	new default ECDSA_METHOD

int ECDSA_set_method	(	EC_KEY *	eckey,
		const ECDSA_METHOD *	meth
	)

Sets method to be used for the ECDSA operations

Parameters

eckey	EC_KEY object
meth	new method

Returns: 1 on success and 0 otherwise

void ECDSA_SIG_free ( ECDSA_SIG * sig )

frees a ECDSA_SIG structure

Parameters

sig	pointer to the ECDSA_SIG structure

ECDSA_SIG* ECDSA_SIG_new ( void )

Allocates and initialize a ECDSA_SIG structure

Returns: pointer to a ECDSA_SIG structure or NULL if an error occurred

int ECDSA_sign	(	int	type,
		const unsigned char *	dgst,
		int	dgstlen,
		unsigned char *	sig,
		unsigned int *	siglen,
		EC_KEY *	eckey
	)

Computes ECDSA signature of a given hash value using the supplied private key (note: sig must point to ECDSA_size(eckey) bytes of memory).

Parameters

type	this parameter is ignored
dgst	pointer to the hash value to sign
dgstlen	length of the hash value
sig	memory for the DER encoded created signature
siglen	pointer to the length of the returned signature
eckey	EC_KEY object containing a private EC key

Returns: 1 on success and 0 otherwise

int ECDSA_sign_ex	(	int	type,
		const unsigned char *	dgst,
		int	dgstlen,
		unsigned char *	sig,
		unsigned int *	siglen,
		const BIGNUM *	kinv,
		const BIGNUM *	rp,
		EC_KEY *	eckey
	)

Computes ECDSA signature of a given hash value using the supplied private key (note: sig must point to ECDSA_size(eckey) bytes of memory).

Parameters

type	this parameter is ignored
dgst	pointer to the hash value to sign
dgstlen	length of the hash value
sig	buffer to hold the DER encoded signature
siglen	pointer to the length of the returned signature
kinv	BIGNUM with a pre-computed inverse k (optional)
rp	BIGNUM with a pre-computed rp value (optioanl), see ECDSA_sign_setup
eckey	EC_KEY object containing a private EC key

Returns: 1 on success and 0 otherwise

int ECDSA_sign_setup	(	EC_KEY *	eckey,
		BN_CTX *	ctx,
		BIGNUM **	kinv,
		BIGNUM **	rp
	)

Precompute parts of the signing operation

Parameters

eckey	EC_KEY object containing a private EC key
ctx	BN_CTX object (optional)
kinv	BIGNUM pointer for the inverse of k
rp	BIGNUM pointer for x coordinate of k * generator

Returns: 1 on success and 0 otherwise

int ECDSA_size ( const EC_KEY * eckey )

Returns the maximum length of the DER encoded signature

Parameters

eckey EC_KEY object

Returns: numbers of bytes required for the DER encoded signature

int ECDSA_verify	(	int	type,
		const unsigned char *	dgst,
		int	dgstlen,
		const unsigned char *	sig,
		int	siglen,
		EC_KEY *	eckey
	)

Verifies that the given signature is valid ECDSA signature of the supplied hash value using the specified public key.

Parameters

type	this parameter is ignored
dgst	pointer to the hash value
dgstlen	length of the hash value
sig	pointer to the DER encoded signature
siglen	length of the DER encoded signature
eckey	EC_KEY object containing a public EC key

Returns: 1 if the signature is valid, 0 if the signature is invalid and -1 on error

int i2d_ECDSA_SIG	(	const ECDSA_SIG *	sig,
		unsigned char **	pp
	)

DER encode content of ECDSA_SIG object (note: this function modifies *pp (*pp += length of the DER encoded signature)).

Parameters

sig	pointer to the ECDSA_SIG object
pp	pointer to a unsigned char pointer for the output or NULL

Returns: the length of the DER encoded ECDSA_SIG object or 0

Functions

Detailed Description

Function Documentation