NAME
        Net::Nessus::Client - A Nessus client module

SYNOPSIS
        # Connect to the Nessus Server
        require Net::Nessus::Client;
        my $client = Net::Nessus::Client->new('host' => 'localhost',
                                              'port' => '3001',
                                              'user' => 'joe',
                                              'password' => 'my_password');

DESCRIPTION
    The Nessus program is a Client/Server application offering a
    framework for lots of security related scanners, so-called
    plugins. The idea is not to create a separate scanner for any
    possible security hole, but to reimplement only the most
    important parts and let the Nessus Server (nessusd) do the most
    part of the work.

    Clients are typically available as GUI applications, for example
    based on the GTK (nessus), Java or Win32 applications. This
    module is another Nessus client written in Perl, but without
    GUI.

    You start using the module by opening a connection to a Nessus
    Server: This will create a Nessus client object for you. This
    object offers methods that you can later use, for example
    retrieving the list of available plugins, start a scan, set
    preferences and so on.

METHOD INTERFACE
  Creating a client object

      require Net::Nessus::Client;
      my $client = Net::Nessus::Client->new(%attr);

    (Class Method) The new method is the client constructor. It
    receives a set of attributes that are required for opening the
    connection, for example

    A Perl exception is thrown in case of trouble.

    host
    port    Host name (or IP address) and port number of the Nessus
            servers machine. The defaults are *localhost* and
            *3001*, as accepted by the IO::Socket modules *new*
            constructor. You may as well use other attributes of
            this constructor, for example *Timeout*. the IO::Socket
            manpage.

    user
    password
            User name and password to use for logging into the
            Nessus server. There are no defaults, you must set these
            attributes.

    ntp_proto
            An optional version of the NTP protocol to run. Defaults
            to the highest available number, 1.1 as of this writing.

    Example: Log into the Nessus server running at machine
    "gate.company.com", port 2367 as user "joe" with password
    "what_password" and NTP version 1.0:

      require Net::Nessus::Client;
      my $client = Net::Nessus::Client->new('host' => 'gate.company.com',
                                            'port' => 2367,
                                            'user' => 'joe',
                                            'password' => 'what_password',
                                            'ntp_proto' => '1.0');

  Reading the plugin list

      my $plugins = $self->Plugins();
      my $prefs = $self->Prefs();
      my $rules = $self->Rules();

    (Instance Methods) Read the plugin list, the current preferences
    or the list of rules. The plugin list is an array of hash refs,
    each hash ref with attributes *id*, *category* and so on. The
    prefs are a single hash ref of name/value pairs and the rules
    are an array ref of strings.

    When talking to an NTP/1.0 server, the Prefs() and Rules()
    methods will return undef.

    Examples:

      my $plugins = $self->Plugins();
      print("The first plugins ID is ", $plugins->[0]->{'id'}, "\n");
      print("The second plugins description is ",
            $plugins->[1]->{'description'}, "\n");
      my $prefs = $self->Prefs();
      print "\nThe current prefs are:\n";
      while (my($var, $val) = each %$prefs) {
        print "  $var = $val\n";
      }
      my $rules = $self->Rules();
      print "\nThe current rules are:\n";
      foreach my $rule (@$rules) {
        print "  $rule\n";
      }

  Sending a message to the server

      $client->Print($msg);

    (Instance Method) The print method is used for sending a
    previously created message to the server. Depending on the
    message type you should continue calling the *GetMsg* method.

    Example:

      my $rules = ['n:*.fr;', 'y:*.my.de;'];
      my $msg = Net::Nessus::Message::Rules($rules);
      $client->print($msg);

  Reading a message from the server

      $msg = $client->GetMsg($type, $timeout);

    (Instance method) The *GetMsg* method is reading a message from
    the server. If the argument $type is undef, then any message is
    accepted, otherwise any message other message type is treated as
    an error. Valid message types are PLUGIN_LIST, PREFERENCES and
    so on.

    If the argument $timeout is given, then an error will be
    triggered, if the server is not sending any message for that
    much seconds. If no timeout is given, then the default timeout
    will be used.

  Launching an attack

      my $messages = $client->Attack(@hosts);
      $client->ShowSTATUS($msg);
      $client->ShowPORT($msg);
      $client->ShowHOLE($msg);
      $client->ShowINFO($msg);
      $client->ShowPLUGINS_ORDER($msg);
      $client->ShowBYE($msg);

    (Instance Methods) An attack can be launched by calling the
    clients *Attack* method. While the attack is running, the Nessus
    server will send PLUGINS_ORDER, STATUS, PORT, HOLE and INFO
    messages and finally a BYE message. If the client receives such
    a message, he will call the corresponding Show method, for
    example *ShowPLUGINS_ORDER* or *ShowPORT*.

    The default implementations of these messages will create a hash
    ref. The hash refs keys are port numbers, a special key being
    the word general. The hash refs values are hash refs again, the
    keys being the words PORT, HOLE and INFO. The values are array
    refs of corresponding messages. That is, you find all security
    holes (if any) of the targets FTP port as follows:

      my @ftp_holes = @{$messages->{'21'}->{'PORT'}};

    Finally the hosts are used to build a top hash ref, the values
    being as described above for the respective host.

AUTHOR AND COPYRIGHT
    The Net::Nessus package is

      Copyright (C) 1998    Jochen Wiedmann
                            Am Eisteich 9
                            72555 Metzingen
                            Germany

                            Phone: +49 7123 14887
                            Email: joe@ispsoft.de
      All rights reserved.

    You may distribute under the terms of either the GNU General
    Public License or the Artistic License, as specified in the Perl
    README file.

    $Id: Client.pm,v 1.5 1999/01/31 14:03:19 joe Exp $

SEE ALSO
    the Net::Nessus::Client(3) manpage

