xref: /freebsd/crypto/openssl/doc/man3/DSA_dup_DH.pod (revision 315ee00f)
1=pod
2
3=head1 NAME
4
5DSA_dup_DH - create a DH structure out of DSA structure
6
7=head1 SYNOPSIS
8
9 #include <openssl/dsa.h>
10
11The following functions have been deprecated since OpenSSL 3.0, and can be
12hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value,
13see L<openssl_user_macros(7)>:
14
15 DH *DSA_dup_DH(const DSA *r);
16
17=head1 DESCRIPTION
18
19The function described on this page is deprecated. There is no direct
20replacement, applications should use the EVP_PKEY APIs for Diffie-Hellman
21operations.
22
23DSA_dup_DH() duplicates DSA parameters/keys as DH parameters/keys. q
24is lost during that conversion, but the resulting DH parameters
25contain its length.
26
27=head1 RETURN VALUES
28
29DSA_dup_DH() returns the new B<DH> structure, and NULL on error. The
30error codes can be obtained by L<ERR_get_error(3)>.
31
32=head1 NOTE
33
34Be careful to avoid small subgroup attacks when using this.
35
36=head1 SEE ALSO
37
38L<DH_new(3)>, L<DSA_new(3)>, L<ERR_get_error(3)>
39
40=head1 HISTORY
41
42This function was deprecated in OpenSSL 3.0.
43
44=head1 COPYRIGHT
45
46Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.
47
48Licensed under the Apache License 2.0 (the "License").  You may not use
49this file except in compliance with the License.  You can obtain a copy
50in the file LICENSE in the source distribution or at
51L<https://www.openssl.org/source/license.html>.
52
53=cut
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