=head1 NAME
-EC_GROUP_copy, EC_GROUP_dup, EC_GROUP_method_of, EC_GROUP_set_generator, EC_GROUP_get0_generator, EC_GROUP_get_order, EC_GROUP_get_cofactor, EC_GROUP_set_curve_name, EC_GROUP_get_curve_name, EC_GROUP_set_asn1_flag, EC_GROUP_get_asn1_flag, EC_GROUP_set_point_conversion_form, EC_GROUP_get_point_conversion_form, EC_GROUP_get0_seed, EC_GROUP_get_seed_len, EC_GROUP_set_seed, EC_GROUP_get_degree, EC_GROUP_check, EC_GROUP_check_discriminant, EC_GROUP_cmp, EC_GROUP_get_basis_type, EC_GROUP_get_trinomial_basis, EC_GROUP_get_pentanomial_basis - Functions for manipulating B<EC_GROUP> objects.
+EC_GROUP_get0_order, EC_GROUP_order_bits, EC_GROUP_get0_cofactor,
+EC_GROUP_copy, EC_GROUP_dup, EC_GROUP_method_of, EC_GROUP_set_generator,
+EC_GROUP_get0_generator, EC_GROUP_get_order, EC_GROUP_get_cofactor,
+EC_GROUP_set_curve_name, EC_GROUP_get_curve_name, EC_GROUP_set_asn1_flag,
+EC_GROUP_get_asn1_flag, EC_GROUP_set_point_conversion_form,
+EC_GROUP_get_point_conversion_form, EC_GROUP_get0_seed,
+EC_GROUP_get_seed_len, EC_GROUP_set_seed, EC_GROUP_get_degree,
+EC_GROUP_check, EC_GROUP_check_discriminant, EC_GROUP_cmp,
+EC_GROUP_get_basis_type, EC_GROUP_get_trinomial_basis,
+EC_GROUP_get_pentanomial_basis
+- Functions for manipulating EC_GROUP objects
=head1 SYNOPSIS
#include <openssl/ec.h>
- #include <openssl/bn.h>
int EC_GROUP_copy(EC_GROUP *dst, const EC_GROUP *src);
EC_GROUP *EC_GROUP_dup(const EC_GROUP *src);
const EC_POINT *EC_GROUP_get0_generator(const EC_GROUP *group);
int EC_GROUP_get_order(const EC_GROUP *group, BIGNUM *order, BN_CTX *ctx);
+ const BIGNUM *EC_GROUP_get0_order(const EC_GROUP *group);
+ int EC_GROUP_order_bits(const EC_GROUP *group);
int EC_GROUP_get_cofactor(const EC_GROUP *group, BIGNUM *cofactor, BN_CTX *ctx);
+ const BIGNUM *EC_GROUP_get0_cofactor(const EC_GROUP *group);
void EC_GROUP_set_curve_name(EC_GROUP *group, int nid);
int EC_GROUP_get_curve_name(const EC_GROUP *group);
int EC_GROUP_get_basis_type(const EC_GROUP *);
int EC_GROUP_get_trinomial_basis(const EC_GROUP *, unsigned int *k);
- int EC_GROUP_get_pentanomial_basis(const EC_GROUP *, unsigned int *k1,
- unsigned int *k2, unsigned int *k3);
+ int EC_GROUP_get_pentanomial_basis(const EC_GROUP *, unsigned int *k1,
+ unsigned int *k2, unsigned int *k3);
=head1 DESCRIPTION
EC_GROUP_method_of obtains the EC_METHOD of B<group>.
-EC_GROUP_set_generator sets curve paramaters that must be agreed by all participants using the curve. These
-paramaters include the B<generator>, the B<order> and the B<cofactor>. The B<generator> is a well defined point on the
+EC_GROUP_set_generator sets curve parameters that must be agreed by all participants using the curve. These
+parameters include the B<generator>, the B<order> and the B<cofactor>. The B<generator> is a well defined point on the
curve chosen for cryptographic operations. Integers used for point multiplications will be between 0 and
n-1 where n is the B<order>. The B<order> multiplied by the B<cofactor> gives the number of points on the curve.
1.1.0 and later the named curve form is the default.
The point_conversion_form for a curve controls how EC_POINT data is encoded as ASN1 as defined in X9.62 (ECDSA).
-point_conversion_form_t is an enum defined as follows:
+point_conversion_form_t is an enum defined as follows:
typedef enum {
- /** the point is encoded as z||x, where the octet z specifies
- * which solution of the quadratic equation y is */
- POINT_CONVERSION_COMPRESSED = 2,
- /** the point is encoded as z||x||y, where z is the octet 0x02 */
- POINT_CONVERSION_UNCOMPRESSED = 4,
- /** the point is encoded as z||x||y, where the octet z specifies
+ /** the point is encoded as z||x, where the octet z specifies
+ * which solution of the quadratic equation y is */
+ POINT_CONVERSION_COMPRESSED = 2,
+ /** the point is encoded as z||x||y, where z is the octet 0x04 */
+ POINT_CONVERSION_UNCOMPRESSED = 4,
+ /** the point is encoded as z||x||y, where the octet z specifies
* which solution of the quadratic equation y is */
- POINT_CONVERSION_HYBRID = 6
+ POINT_CONVERSION_HYBRID = 6
} point_conversion_form_t;
-
For POINT_CONVERSION_UNCOMPRESSED the point is encoded as an octet signifying the UNCOMPRESSED form has been used followed by
the octets for x, followed by the octets for y.
For any given x co-ordinate for a point on a curve it is possible to derive two possible y values. For
POINT_CONVERSION_COMPRESSED the point is encoded as an octet signifying that the COMPRESSED form has been used AND which of
-the two possible solutions for y has been used, followed by the octets for x.
+the two possible solutions for y has been used, followed by the octets for x.
For POINT_CONVERSION_HYBRID the point is encoded as an octet signifying the HYBRID form has been used AND which of the two
possible solutions for y has been used, followed by the octets for x, followed by the octets for y.
and EC_GROUP_get_degree return the order, cofactor, curve name (NID), ASN1 flag, point_conversion_form and degree for the
specified curve respectively. If there is no curve name associated with a curve then EC_GROUP_get_curve_name will return 0.
+EC_GROUP_get0_order() returns an internal pointer to the group order.
+EC_GROUP_get_order_bits() returns the number of bits in the group order.
+EC_GROUP_get0_cofactor() returns an internal pointer to the group cofactor.
+
EC_GROUP_get0_seed returns a pointer to the seed that was used to generate the parameter b, or NULL if the seed is not
specified. EC_GROUP_get_seed_len returns the length of the seed or 0 if the seed is not specified.
L<EC_POINT_new(3)>, L<EC_POINT_add(3)>, L<EC_KEY_new(3)>,
L<EC_GFp_simple_method(3)>, L<d2i_ECPKParameters(3)>
+=head1 COPYRIGHT
+
+Copyright 2013-2016 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<https://www.openssl.org/source/license.html>.
+
=cut