1=pod 2 3=head1 NAME 4 5DH_size, DH_bits, DH_security_bits - get Diffie-Hellman prime size and 6security bits 7 8=head1 SYNOPSIS 9 10 #include <openssl/dh.h> 11 12The following functions have been deprecated since OpenSSL 3.0, and can be 13hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value, 14see L<openssl_user_macros(7)>: 15 16 int DH_bits(const DH *dh); 17 18 int DH_size(const DH *dh); 19 20 int DH_security_bits(const DH *dh); 21 22=head1 DESCRIPTION 23 24The functions described on this page are deprecated. 25Applications should instead use L<EVP_PKEY_get_bits(3)>, 26L<EVP_PKEY_get_security_bits(3)> and L<EVP_PKEY_get_size(3)>. 27 28DH_bits() returns the number of significant bits. 29 30B<dh> and B<dh-E<gt>p> must not be B<NULL>. 31 32DH_size() returns the Diffie-Hellman prime size in bytes. It can be used 33to determine how much memory must be allocated for the shared secret 34computed by L<DH_compute_key(3)>. 35 36DH_security_bits() returns the number of security bits of the given B<dh> 37key. See L<BN_security_bits(3)>. 38 39=head1 RETURN VALUES 40 41DH_bits() returns the number of bits in the key, or -1 if 42B<dh> doesn't hold any key parameters. 43 44DH_size() returns the prime size of Diffie-Hellman in bytes, or -1 if 45B<dh> doesn't hold any key parameters. 46 47DH_security_bits() returns the number of security bits, or -1 if 48B<dh> doesn't hold any key parameters. 49 50=head1 SEE ALSO 51 52L<EVP_PKEY_get_bits(3)>, 53L<DH_new(3)>, L<DH_generate_key(3)>, 54L<BN_num_bits(3)> 55 56=head1 HISTORY 57 58All functions were deprecated in OpenSSL 3.0. 59 60=head1 COPYRIGHT 61 62Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved. 63 64Licensed under the Apache License 2.0 (the "License"). You may not use 65this file except in compliance with the License. You can obtain a copy 66in the file LICENSE in the source distribution or at 67L<https://www.openssl.org/source/license.html>. 68 69=cut 70