From 400be4ef986dec8c1a1679b725801a8fc23ff6b9 Mon Sep 17 00:00:00 2001
From: Bruce Momjian <bruce@momjian.us>
Date: Sat, 29 Dec 2007 03:36:56 +0000
Subject: [PATCH] Document problem with NULL SSL ciphers and man-in-the-middle
 attacks.

---
 doc/src/sgml/runtime.sgml | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 356a1d295c..166d86a623 100644
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.397 2007/12/25 17:06:52 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.398 2007/12/29 03:36:56 momjian Exp $ -->
 
 <chapter Id="runtime">
  <title>Operating System Environment</title>
@@ -1604,7 +1604,10 @@ $ <userinput>kill -INT `head -1 /usr/local/pgsql/data/postmaster.pid`</userinput
    ciphers can be specified in the <productname>OpenSSL</productname>
    configuration file, you can specify ciphers specifically for use by
    the database server by modifying <xref linkend="guc-ssl-ciphers"> in
-   <filename>postgresql.conf</>.
+   <filename>postgresql.conf</>.  It is possible to allow authentication
+   without the overhead of encryption by using <literal>NULL-SHA</> or
+   <literal>NULL-MD5</> ciphers.  However, a man-in-the-middle could read
+   and pass communications between client and server.
   </para>
 
   <para>