DSA_dup_DH - create a DH structure out of DSA structure

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       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 in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.

3.5.0                                              2025-06-04                                   DSA_DUP_DH(3SSL)

       The function described on this page is deprecated. There is no direct replacement, applications should
       use the EVP_PKEY APIs for Diffie-Hellman operations.

       DSA_dup_DH() duplicates DSA parameters/keys as DH parameters/keys. q is lost during that conversion, but
       the resulting DH parameters contain its length.

       This function was deprecated in OpenSSL 3.0.

       DSA_dup_DH - create a DH structure out of DSA structure

       Be careful to avoid small subgroup attacks when using this.

DSA_dup_DH() returns the new DH structure, and NULL on error. The error codes can be obtained by
       ERR_get_error(3).

DH_new(3), DSA_new(3), ERR_get_error(3)

        #include <openssl/dsa.h>

       The following functions have been deprecated since OpenSSL 3.0, and can be hidden entirely by defining
       OPENSSL_API_COMPAT with a suitable version value, see openssl_user_macros(7):

        DH *DSA_dup_DH(const DSA *r);