EC_GROUP_check, EC_GROUP_check_named_curve,
EC_GROUP_check_discriminant, EC_GROUP_cmp,
EC_GROUP_get_basis_type, EC_GROUP_get_trinomial_basis,
-EC_GROUP_get_pentanomial_basis, EC_GROUP_get0_field
+EC_GROUP_get_pentanomial_basis, EC_GROUP_get0_field,
+EC_GROUP_get_field_type
- Functions for manipulating EC_GROUP objects
=head1 SYNOPSIS
int EC_GROUP_copy(EC_GROUP *dst, const EC_GROUP *src);
EC_GROUP *EC_GROUP_dup(const EC_GROUP *src);
- const EC_METHOD *EC_GROUP_method_of(const EC_GROUP *group);
-
int EC_GROUP_set_generator(EC_GROUP *group, const EC_POINT *generator,
const BIGNUM *order, const BIGNUM *cofactor);
const EC_POINT *EC_GROUP_get0_generator(const EC_GROUP *group);
void EC_GROUP_set_point_conversion_form(EC_GROUP *group, point_conversion_form_t form);
point_conversion_form_t EC_GROUP_get_point_conversion_form(const EC_GROUP *group);
- unsigned char *EC_GROUP_get0_seed(const EC_GROUP *x);
- size_t EC_GROUP_get_seed_len(const EC_GROUP *);
- size_t EC_GROUP_set_seed(EC_GROUP *, const unsigned char *, size_t len);
+ unsigned char *EC_GROUP_get0_seed(const EC_GROUP *group);
+ size_t EC_GROUP_get_seed_len(const EC_GROUP *group);
+ size_t EC_GROUP_set_seed(EC_GROUP *group, const unsigned char *, size_t len);
int EC_GROUP_get_degree(const EC_GROUP *group);
int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, BN_CTX *ctx);
- 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,
+ int EC_GROUP_get_basis_type(const EC_GROUP *group);
+ int EC_GROUP_get_trinomial_basis(const EC_GROUP *group, unsigned int *k);
+ int EC_GROUP_get_pentanomial_basis(const EC_GROUP *group, unsigned int *k1,
unsigned int *k2, unsigned int *k3);
+ int EC_GROUP_get_field_type(const EC_GROUP *group);
+
+The following function has been deprecated since OpenSSL 3.0, and can be
+hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value,
+see L<openssl_user_macros(7)>:
+
+ const EC_METHOD *EC_GROUP_method_of(const EC_GROUP *group);
+
=head1 DESCRIPTION
EC_GROUP_copy() copies the curve B<src> into B<dst>. Both B<src> and B<dst> must use the same EC_METHOD.
EC_GROUP object.
EC_GROUP_method_of() obtains the EC_METHOD of B<group>.
+This function was deprecated in OpenSSL 3.0, since EC_METHOD is no longer a public concept.
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
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
+For any given x coordinate 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.
EC_GROUP_set_seed() and passing a pointer to a memory block, along with the length of the seed. Again, the EC library will not use
this seed value, although it will be preserved in any ASN1 based communications.
-EC_GROUP_get_degree() gets the degree of the field. For Fp fields this will be the number of bits in p. For F2^m fields this will be
-the value m.
+EC_GROUP_get_degree() gets the degree of the field.
+For Fp fields this will be the number of bits in p.
+For F2^m fields this will be the value m.
+
+EC_GROUP_get_field_type() identifies what type of field the EC_GROUP structure supports,
+which will be either F2^m or Fp.
The function EC_GROUP_check_discriminant() calculates the discriminant for the curve and verifies that it is valid.
For a curve defined over Fp the discriminant is given by the formula 4*a^3 + 27*b^2 whilst for F2^m curves the discriminant is
simply b. In either case for the curve to be valid the discriminant must be non zero.
-The function EC_GROUP_check() performs a number of checks on a curve to verify that it is valid. Checks performed include
+The function EC_GROUP_check() behaves in the following way:
+For the OpenSSL default provider it performs a number of checks on a curve to verify that it is valid. Checks performed include
verifying that the discriminant is non zero; that a generator has been defined; that the generator is on the curve and has
-the correct order.
+the correct order. For the OpenSSL FIPS provider it uses EC_GROUP_check_named_curve() to conform to SP800-56Ar3.
The function EC_GROUP_check_named_curve() determines if the group's domain parameters match one of the built-in curves supported by the library.
The curve name is returned as a B<NID> if it matches. If the group's domain parameters have been modified then no match will be found.
EC_GROUP_get_degree() returns the degree for B<group> or 0 if the operation is not supported by the underlying group implementation.
+EC_GROUP_get_field_type() returns either B<NID_X9_62_prime_field> for prime curves
+or B<NID_X9_62_characteristic_two_field> for binary curves;
+these values are defined in the F<< <openssl/obj_mac.h> >> header file.
+
EC_GROUP_check_named_curve() returns the nid of the matching named curve, otherwise it returns 0 for no match, or -1 on error.
EC_GROUP_get0_order() returns an internal pointer to the group order.
EC_GROUP_cmp() returns 0 if the curves are equal, 1 if they are not equal, or -1 on error.
-EC_GROUP_get_basis_type() returns the values NID_X9_62_tpBasis or NID_X9_62_ppBasis (as defined in <openssl/obj_mac.h>) for a
+EC_GROUP_get_basis_type() returns the values NID_X9_62_tpBasis or NID_X9_62_ppBasis (as defined in F<< <openssl/obj_mac.h> >>) for a
trinomial or pentanomial respectively. Alternatively in the event of an error a 0 is returned.
=head1 SEE ALSO
=head1 HISTORY
-The EC_GROUP_check_named_curve() function was added in OpenSSL 3.0.
+EC_GROUP_method_of() was deprecated in OpenSSL 3.0.
+EC_GROUP_get0_field(), EC_GROUP_check_named_curve() and EC_GROUP_get_field_type() were added in OpenSSL 3.0.
+EC_GROUP_get0_order(), EC_GROUP_order_bits() and EC_GROUP_get0_cofactor() were added in OpenSSL 1.1.0.
=head1 COPYRIGHT
-Copyright 2013-2019 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2013-2023 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
projects / openssl.git / blobdiff