=pod =head1 NAME EC_KEY_get_method, EC_KEY_set_method, EC_KEY_new, EC_KEY_get_flags, EC_KEY_set_flags, EC_KEY_clear_flags, EC_KEY_new_by_curve_name, EC_KEY_free, EC_KEY_copy, EC_KEY_dup, EC_KEY_up_ref, EC_KEY_get0_engine, EC_KEY_get0_group, EC_KEY_set_group, EC_KEY_get0_private_key, EC_KEY_set_private_key, EC_KEY_get0_public_key, EC_KEY_set_public_key, EC_KEY_get_conv_form, EC_KEY_set_conv_form, EC_KEY_set_asn1_flag, EC_KEY_precompute_mult, EC_KEY_generate_key, EC_KEY_check_key, EC_KEY_set_public_key_affine_coordinates, EC_KEY_oct2key, EC_KEY_key2buf, EC_KEY_oct2priv, EC_KEY_priv2oct, EC_KEY_priv2buf - Functions for creating, destroying and manipulating EC_KEY objects =head1 SYNOPSIS #include EC_KEY *EC_KEY_new(void); int EC_KEY_get_flags(const EC_KEY *key); void EC_KEY_set_flags(EC_KEY *key, int flags); void EC_KEY_clear_flags(EC_KEY *key, int flags); EC_KEY *EC_KEY_new_by_curve_name(int nid); void EC_KEY_free(EC_KEY *key); EC_KEY *EC_KEY_copy(EC_KEY *dst, const EC_KEY *src); EC_KEY *EC_KEY_dup(const EC_KEY *src); int EC_KEY_up_ref(EC_KEY *key); ENGINE *EC_KEY_get0_engine(const EC_KEY *eckey); const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key); int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group); const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key); int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *prv); const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key); int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub); point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key); void EC_KEY_set_conv_form(EC_KEY *eckey, point_conversion_form_t cform); void EC_KEY_set_asn1_flag(EC_KEY *eckey, int asn1_flag); int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx); int EC_KEY_generate_key(EC_KEY *key); int EC_KEY_check_key(const EC_KEY *key); int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, BIGNUM *y); const EC_KEY_METHOD *EC_KEY_get_method(const EC_KEY *key); int EC_KEY_set_method(EC_KEY *key, const EC_KEY_METHOD *meth); int EC_KEY_oct2key(EC_KEY *eckey, const unsigned char *buf, size_t len, BN_CTX *ctx); size_t EC_KEY_key2buf(const EC_KEY *eckey, point_conversion_form_t form, unsigned char **pbuf, BN_CTX *ctx); int EC_KEY_oct2priv(EC_KEY *eckey, const unsigned char *buf, size_t len); size_t EC_KEY_priv2oct(const EC_KEY *eckey, unsigned char *buf, size_t len); size_t EC_KEY_priv2buf(const EC_KEY *eckey, unsigned char **pbuf); =head1 DESCRIPTION An EC_KEY represents a public key and, optionally, the associated private key. A new EC_KEY with no associated curve can be constructed by calling EC_KEY_new(). The reference count for the newly created EC_KEY is initially set to 1. A curve can be associated with the EC_KEY by calling EC_KEY_set_group(). Alternatively a new EC_KEY can be constructed by calling EC_KEY_new_by_curve_name() and supplying the nid of the associated curve. See L for a description of curve names. This function simply wraps calls to EC_KEY_new() and EC_GROUP_new_by_curve_name(). Calling EC_KEY_free() decrements the reference count for the EC_KEY object, and if it has dropped to zero then frees the memory associated with it. If B is NULL nothing is done. EC_KEY_copy() copies the contents of the EC_KEY in B into B. EC_KEY_dup() creates a new EC_KEY object and copies B into it. EC_KEY_up_ref() increments the reference count associated with the EC_KEY object. EC_KEY_get0_engine() returns a handle to the ENGINE that has been set for this EC_KEY object. EC_KEY_generate_key() generates a new public and private key for the supplied B object. B must have an EC_GROUP object associated with it before calling this function. The private key is a random integer (0 < priv_key < order, where I is the order of the EC_GROUP object). The public key is an EC_POINT on the curve calculated by multiplying the generator for the curve by the private key. EC_KEY_check_key() performs various sanity checks on the EC_KEY object to confirm that it is valid. EC_KEY_set_public_key_affine_coordinates() sets the public key for B based on its affine co-ordinates; i.e., it constructs an EC_POINT object based on the supplied B and B values and sets the public key to be this EC_POINT. It also performs certain sanity checks on the key to confirm that it is valid. The functions EC_KEY_get0_group(), EC_KEY_set_group(), EC_KEY_get0_private_key(), EC_KEY_set_private_key(), EC_KEY_get0_public_key(), and EC_KEY_set_public_key() get and set the EC_GROUP object, the private key, and the EC_POINT public key for the B respectively. The functions EC_KEY_get_conv_form() and EC_KEY_set_conv_form() get and set the point_conversion_form for the B. For a description of point_conversion_forms please see L. EC_KEY_set_flags() sets the flags in the B parameter on the EC_KEY object. Any flags that are already set are left set. The flags currently defined are EC_FLAG_NON_FIPS_ALLOW and EC_FLAG_FIPS_CHECKED. In addition there is the flag EC_FLAG_COFACTOR_ECDH which is specific to ECDH. EC_KEY_get_flags() returns the current flags that are set for this EC_KEY. EC_KEY_clear_flags() clears the flags indicated by the B parameter; all other flags are left in their existing state. EC_KEY_set_asn1_flag() sets the asn1_flag on the underlying EC_GROUP object (if set). Refer to L for further information on the asn1_flag. EC_KEY_precompute_mult() stores multiples of the underlying EC_GROUP generator for faster point multiplication. See also L. EC_KEY_oct2key() and EC_KEY_key2buf() are identical to the functions EC_POINT_oct2point() and EC_KEY_point2buf() except they use the public key EC_POINT in B. EC_KEY_oct2priv() and EC_KEY_priv2oct() convert between the private key component of B and octet form. The octet form consists of the content octets of the B OCTET STRING in an B ASN.1 structure. The function EC_KEY_priv2oct() must be supplied with a buffer long enough to store the octet form. The return value provides the number of octets stored. Calling the function with a NULL buffer will not perform the conversion but will just return the required buffer length. The function EC_KEY_priv2buf() allocates a buffer of suitable length and writes an EC_KEY to it in octet format. The allocated buffer is written to B<*pbuf> and its length is returned. The caller must free up the allocated buffer with a call to OPENSSL_free(). Since the allocated buffer value is written to B<*pbuf> the B parameter B be B. EC_KEY_priv2buf() converts an EC_KEY private key into an allocated buffer. =head1 RETURN VALUES EC_KEY_new(), EC_KEY_new_by_curve_name() and EC_KEY_dup() return a pointer to the newly created EC_KEY object, or NULL on error. EC_KEY_get_flags() returns the flags associated with the EC_KEY object as an integer. EC_KEY_copy() returns a pointer to the destination key, or NULL on error. EC_KEY_get0_engine() returns a pointer to an ENGINE, or NULL if it wasn't set. EC_KEY_up_ref(), EC_KEY_set_group(), EC_KEY_set_private_key(), EC_KEY_set_public_key(), EC_KEY_precompute_mult(), EC_KEY_generate_key(), EC_KEY_check_key(), EC_KEY_set_public_key_affine_coordinates(), EC_KEY_oct2key() and EC_KEY_oct2priv() return 1 on success or 0 on error. EC_KEY_get0_group() returns the EC_GROUP associated with the EC_KEY. EC_KEY_get0_private_key() returns the private key associated with the EC_KEY. EC_KEY_get_conv_form() return the point_conversion_form for the EC_KEY. EC_KEY_key2buf(), EC_KEY_priv2oct() and EC_KEY_priv2buf() return the length of the buffer or 0 on error. =head1 SEE ALSO L, L, L, L, L, L, L =head1 COPYRIGHT Copyright 2013-2017 The OpenSSL Project Authors. All Rights Reserved. Licensed under the OpenSSL license (the "License"). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at L. =cut