Added PostgreSQL UDF to execute commands on the underlying system:

* sys_eval() to return the standard output
* sys_exec() to return the exit status

Inspired by lib_mysqludf_sys 0.0.3 (https://svn.sqlmap.org/sqlmap/trunk/sqlmap/extra/mysqludfsys/)

extra/postgresqludfsys/lib_postgresqludf_sys/install.sh

@@ -0,0 +1,43 @@
+#!/bin/bash
+# lib_postgresqludf_sys - a library with miscellaneous (operating) system level functions
+# Copyright (C) 2009  Bernardo Damele A. G.
+# web: http://bernardodamele.blogspot.com/
+# email: bernardo.damele@gmail.com
+# 
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+# 
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+# 
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+echo "Compiling the PostgreSQL UDF"
+make
+
+if test $? -ne 0; then
+	echo "ERROR: You need postgresql-server development software installed "
+	echo "to be able to compile this UDF, on Debian/Ubuntu just run:"
+	echo "apt-get install postgresql-server-dev-8.3"
+	exit 1
+else
+	echo "PostgreSQL UDF compiled successfully"
+fi
+
+echo -e "\nPlease provide your PostgreSQL 'postgres' user's password"
+
+/usr/lib/postgresql/8.3/bin/psql -h 127.0.0.1 -p 5432 -U postgres -q template1 < lib_postgresqludf_sys.sql
+#psql -h 127.0.0.1 -p 5432 -U postgres -q template1 < lib_postgresqludf_sys.sql
+
+if test $? -ne 0; then
+	echo "ERROR: unable to install the UDF"
+	exit 1
+else
+	echo "PostgreSQL UDF installed successfully"
+fi