#use wml::openssl-macros area=docs page=DSA_dup_DH

<title>Documents, DSA_dup_DH(3)</title>

<h1>DSA_dup_DH(3)</h1>

#use wml::imp::generic

{:
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	<LI><A HREF="#NAME">NAME</A>
	<LI><A HREF="#SYNOPSIS">SYNOPSIS</A>
	<LI><A HREF="#DESCRIPTION">DESCRIPTION</A>
	<LI><A HREF="#RETURN_VALUE">RETURN VALUE</A>
	<LI><A HREF="#NOTE">NOTE</A>
	<LI><A HREF="#SEE_ALSO">SEE ALSO</A>
	<LI><A HREF="#HISTORY">HISTORY</A>
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<H1><A NAME="NAME">NAME</A></H1>
<P>
DSA_dup_DH - create a DH structure out of DSA structure

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<H1><A NAME="SYNOPSIS">SYNOPSIS</A></H1>
<PRE> #include &lt;openssl/dsa.h&gt;
</PRE>
<PRE> DH * DSA_dup_DH(const DSA *r);
</PRE>
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<H1><A NAME="DESCRIPTION">DESCRIPTION</A></H1>
<P>
<CODE>DSA_dup_DH()</CODE> duplicates DSA parameters/keys as DH
parameters/keys. q is lost during that conversion, but the resulting DH
parameters contain its length.

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<H1><A NAME="RETURN_VALUE">RETURN VALUE</A></H1>
<P>
<CODE>DSA_dup_DH()</CODE> returns the new <STRONG>DH</STRONG> structure, and NULL on error. The error codes can be obtained by <A HREF="../crypto/ERR_get_error.html#">ERR_get_error(3)</A>.

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<H1><A NAME="NOTE">NOTE</A></H1>
<P>
Be careful to avoid small subgroup attacks when using this.

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<H1><A NAME="SEE_ALSO">SEE ALSO</A></H1>
<P>
<A HREF="../crypto/dh.html#">dh(3)</A>, <A HREF="../crypto/dsa.html#">dsa(3)</A>, <A HREF="../crypto/ERR_get_error.html#">ERR_get_error(3)</A>



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<H1><A NAME="HISTORY">HISTORY</A></H1>
<P>
<CODE>DSA_dup_DH()</CODE> was added in OpenSSL 0.9.4.

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:}