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<sect1 id="pgcrypto">

<title>pgcrypto</title>

<para>

Computes a binary hash of the given <parameter>data</>.

<parameter>type</> is the algorithm to use.

Standard algorithms are <literal>md5</literal> and

<literal>sha1</literal>. If <filename>pgcrypto</> was built with

Standard algorithms are <literal>md5</literal>, <literal>sha1</literal>,

<literal>sha224</literal>, <literal>sha256</literal>,

<literal>sha384</literal> and <literal>sha512</literal>.

If <filename>pgcrypto</> was built with

OpenSSL, more algorithms are available, as detailed in

<xref linkend="pgcrypto-with-without-openssl">.

</para>

<title>PGP encryption functions</title>

<para>

The functions here implement the encryption part of the OpenPGP (RFC2440)

The functions here implement the encryption part of the OpenPGP (RFC4880)

standard. Supported are both symmetric-key and public-key encryption.

</para>

<para>

Which compression algorithm to use. Only available if

<filename>pgcrypto</> was built with zlib.

<productname>PostgreSQL<productname/> was built with zlib.

</para>

<programlisting>

Values:

<para>

Whether to convert <literal>\n</literal> into <literal>\r\n</literal> when

encrypting and <literal>\r\n</literal> to <literal>\n</literal> when

decrypting. RFC2440 specifies that text data should be stored using

decrypting. RFC4880 specifies that text data should be stored using

<literal>\r\n</literal> line-feeds. Use this to get fully RFC-compliant

behavior.

</para>

<para>

Do not protect data with SHA-1. The only good reason to use this

option is to achieve compatibility with ancient PGP products, predating

the addition of SHA-1 protected packets to RFC2440.

the addition of SHA-1 protected packets to RFC4880.

Recent gnupg.org and pgp.com software supports it fine.

</para>

<programlisting>

<itemizedlist>

<listitem>

<para><ulink url="http://www.ietf.org/rfc/rfc2440.txt"></ulink></para>

<para><ulink url="http://www.ietf.org/rfc/rfc4880.txt"></ulink></para>

<para>OpenPGP message format.</para>

</listitem>

<listitem>

<para>

<ulink url="http://www.imc.org/draft-ietf-openpgp-rfc2440bis"></ulink>

</para>

<para>New version of RFC 2440.</para>

</listitem>

<listitem>

<para><ulink url="http://www.ietf.org/rfc/rfc1321.txt"></ulink></para>

<para>The MD5 Message-Digest Algorithm.</para>