Description:
------------
When generating new DSA or DH key using openssl_pkey_new(), then script terminates with Segmentation Fault.

The problem lies in method php_openssl_generate_private_key() (ext/openssl/openssl.c), where "dsaparam" and "dhparam" variables are not initialized.

Both PHP 7.0 and 7.1 are affected.

Test script:
---------------
<?php
    $k = openssl_pkey_new (array ("private_key_type" => OPENSSL_KEYTYPE_DSA));
    echo "Success!";
?>

Expected result:
----------------
Success!

Actual result:
--------------
Segmentation Fault