Document padding constants for OpenSSL functions. (#5758)

Author: kamil-tekiela

reference/openssl/functions/openssl-sign.xml

@@ -71,7 +71,11 @@
     <varlistentry>
      <term><parameter>padding</parameter></term>
      <listitem>
-      <simpara>RSA PSS padding to use.</simpara>
+      <simpara>
+       RSA-PSS padding to use. It can be either
+       <constant>OPENSSL_PKCS1_PADDING</constant>,
+       <constant>OPENSSL_PKCS1_PSS_PADDING</constant>, or <literal>0</literal>.
+      </simpara>
      </listitem>
     </varlistentry>
    </variablelist>

reference/openssl/functions/openssl-verify.xml

@@ -71,7 +71,11 @@ MIIBCgK...</literal>)
     <varlistentry>
      <term><parameter>padding</parameter></term>
      <listitem>
-      <simpara>RSA PSS padding to use.</simpara>
+      <simpara>
+       RSA-PSS padding to use. It can be either
+       <constant>OPENSSL_PKCS1_PADDING</constant>,
+       <constant>OPENSSL_PKCS1_PSS_PADDING</constant>, or <literal>0</literal>.
+      </simpara>
      </listitem>
     </varlistentry>
    </variablelist>