The Auxio Finger Client - afinger

1. INTRODUCTION
------------------------------------------------------------------------------

A finger client is a user information lookup program, displaying
information about login names, real names, shells, login times, idle times,
telephone numbers etc.

Unfortunately, it has become a bit of a threat to security to reveal all of
the information about all logins on a system to everyone.

afinger is a simple configurable finger client written in [1]Perl, and has
been placed under the [2]GNU General Public License, or GNU GPL.

It can be used together with a finger daemon and from the command line,
honours a .nofinger file in home directories, you can set a minimum UID, use
a Fortune program for erroneous requests, and virtually control each part of
the returned information from the configuration options. 

When used stand-alone, afinger will behave like any other finger client such
as the one distributed with your operating system.

If you decide to let remote users retrieve information about the users on
your system, you will need a finger daemon. Mostly run from the inetd 
"super-server", the finger daemon listens for TCP requests received on port
79. Once a remote system connects, the finger daemon reads a single command-
line terminated by a <CRLF> which is passed to the local finger client. The
finger daemon closes its connections as soon as all output is finished.

Thus, if you replace your existing finger with afinger, and have a finger
daemon running, it will use afinger to return the information requested by a
local or remote user, with all fields controlled by either the system
administrator or the "fingered" user him- or herself by placing a .nofinger
file in the home directory, which will disclose all information for this user.

It might also be of interest that afinger does not honour finger relaying,
for example user@host@anotherhost, even if the finger daemon has been 
configured this way. The in.fingerd manual page states regarding forwarding:
"Useful behind firewalls, but probably not wise for security and resource
reasons."

Likewise, requests of the form finger @host are not being honoured, even if
the finger daemon has been configured to allow this.

2. REQUIREMENTS
==============================================================================

  * Perl 5
  * Finger daemon (optional)
  * Xinetd (optional)
  * Fortune (optional)
    
Tested Platforms

  * Linux 2.x, 3.x, 4.x
  * Solaris 2.x
  * HP/UX 10.20
  * FreeBSD

  
3. INSTALLATION
==============================================================================

Please see the file INSTALL, which contains the installation instructions.

4. CONFIGURATION
==============================================================================

The configuration for Auxio finger can be set from the configuration file 
afinger.conf.


   forward   yes   The contents of an existing $HOME/.forward file of the
                   login (for email forwarding) can be displayed.
   network   yes   Allow network queries (user@host). This isn't the same as
                   forwarding.
   login     yes   Display login name.
   name      yes   Display real name.
   home      yes   Display home directory.
   shell     yes   Display shell.
   office    yes   Display office location.
   phone     yes   Display home phone.
   plan      yes   Display $HOME/.plan file.
   proj      yes   Display $HOME/.project file.
   plntime   yes   Display .plan modification time
   prjtime   no    Display .project modification time
   mail      yes   Display mail status information.
   term      yes   Display terminal information.
   pub       yes   Display public key file.
   fortune   no    Use the Fortune program for errors.     
   usecgi    no    Use afinger as CGI script.

5. EXAMPLES
==============================================================================

Output Examples

afinger used locally on a user with an UID below the minimum level returning a
Fortune cookie:

   $ afinger root
   Today's problem: Disk or processor on fire.

Using afinger on a remote user with several fields omitted by afinger:

   $ afinger pkrul@www.auxio.org
   [www.auxio.org]
    Login:                                  Name: Pieter Krul
    Office:                                 Home Phone: +31185189642
    New mail received Mon Dec 25 00:45:38 2000
         Unread since Sun Dec 24 23:00:37 2000
    No Plan.

It is also possible for instance to omit all fields, except a ~/.plan, to
create output similar to the one returned when you finger linux@www.kernel.org

Using afinger on a remote user with all fields enabled:

$ finger pkrul@auxio.org
[ auxio.org (2a01:7c8:aab5:116:1010:1010:1010:1010) ]
Login: pkrul                           Name: Pieter Krul
Directory: /home/pkrul                 Shell: /bin/bash
Office: AUX-I/O, NL                    Home Phone: +31735185555

On since Sep 29 03:06 on pts/0 from 94.211.64.250
On since Sep 29 04:56 on pts/1 from 2001:1af8:fe00:47d::2
On since Sep 29 05:04 on pts/2 from 2a01:7c8:aab5:116::1

Mail forwarded to some_mailbox@example.com
New mail received Sun Apr 26 06:59:45 2015
     Unread since Fri Nov 14 21:52:57 2014

GnuPG/PGP Public Key:

pub   1024D/B1EF0DC4 2000-10-23
      Key fingerprint = 5222 5AA2 636F E6D0 7F14  1670 8C3D CE32 B1EF 0DC4
uid                  Pieter Krul <pkrul@auxio.org>
uid                  Pieter Krul <p@krul.cc>
uid                  Pieter Krul <pieter@krul.cc>
uid                  Pieter Krul <pkrul@snow.nl>
uid                  Pieter Krul <pieter.krul@snow.nl>
uid                  [jpeg image of size 16731]
uid                  [jpeg image of size 5169]
uid                  Pieter Krul <pieter.krul@pharmapartners.nl>
sub   1024g/0A261BCF 2000-10-23

Project:
     Last updated: Tue Sep 29 05:35:25 2015

See https://github.com/pkrul

Plan:
     Last updated: Mon Sep  7 17:32:53 2015

Reformatting Page. Wait...


Another example

$ afinger pkrul@auxio.org

[ auxio.org (2a01:7c8:aab5:116:1010:1010:1010:1010) ]
Login: pkrul                           Name: Pieter Krul
Office: AUX-I/O, NL                    Home Phone: +31735185555

On since Sep 29 09:15 on pts/1 from 94.211.64.250
On since Sep 29 11:02 on pts/2 from 2001:1af8:fe00:47d::2
On since Sep 29 11:05 on pts/4 from 149.210.176.64

New mail received Tue Sep 29 08:44:41 2015
  Unread since Mon Apr 27 23:13:02 2015

Public Key:

pub   1024D/B1EF0DC4 2000-10-23
   Key fingerprint = 5222 5AA2 636F E6D0 7F14  1670 8C3D CE32 B1EF 0DC4
uid                  Pieter Krul <pkrul@auxio.org>
uid                  Pieter Krul <p@krul.cc>
uid                  Pieter Krul <pieter@krul.cc>
uid                  Pieter Krul <pkrul@snow.nl>
uid                  Pieter Krul <pieter.krul@snow.nl>
uid                  [jpeg image of size 16731]
uid                  [jpeg image of size 5169]
uid                  Pieter Krul <pieter.krul@pharmapartners.nl>
sub   1024g/0A261BCF 2000-10-23

Project:
 Last updated: Tue Sep 29 05:35:25 2015

See https://github.com/pkrul

Plan:
 Last updated: Tue Sep 29 06:41:00 2015

Reformatting Page. Wait...



Using afinger as client to query a remote server:

$ afinger hall@bathroom.mit.edu
[ bathroom.mit.edu (18.243.1.73) ]
Random Hall Bathroom Server v2.1

                         Bonfire Kitchen: vacant for 55 days
                         Bonfire  Lounge: vacant for 11 min
                          Pecker  Lounge: *IN*USE* for 26 min
                          Pecker Kitchen: vacant for 55 days
   K 282  L  290 K          Clam Kitchen: vacant for 55 days
   ... ... ... ...          Clam  Lounge: *IN*USE* for 4 min
  | o : o | x : o |          BMF  Lounge: vacant for 3 min
  | o : x | o : o |          BMF Kitchen: vacant for 55 days
  | o : o | x : o |         Loop Kitchen: vacant for 55 days
  | o : x | - : o |         Loop  Lounge: vacant for 11 min
 ~~~~~~~~~~~~~~~~~~~  Black Hole  Lounge: *IN*USE* for 10 min
                      Black Hole Kitchen: vacant for 55 days
      o = vacant!        Destiny Kitchen: vacant for 55 days
      x = in use          Destiny Lounge: *IN*USE* for 4 min
                                     Foo: vacant for 55 days

For more information finger help@bathroom.mit.edu

(2322546)




6. USING FORTUNE COOKIES
==============================================================================

The BOFH fortune cookie file (bofh.dat) is included in the afinger package, in
the cookies directory.
It is based on [3]The BOFH excuses by Jeff Ballard et al.
This file can be copied to eg. /usr/share/games/fortunes/ or wherever
the cookies may be placed on the system, and be used directly by the
fortune program, if installed.
 
See also: http://www.redellipse.net/code/fortune



7. LINKS
==============================================================================

There are currently no Debian, or PKG packages available of Auxio Finger.

The latest version of afinger is 0.43, available as a GNU compressed tar
archive from:

FTP:  ftp://ftp.auxio.org/pub/auxio/afinger/afinger-latest.tar.gz
HTTP: http://www.auxio.org/pub/auxio/afinger/afinger-latest.tar.gz
HTTP: http://www.auxio.net/pub/auxio/afinger/afinger-latest.tar.gz

For other versions of afinger, please visit

FTP:  ftp://ftp.auxio.org/pub/auxio/afinger/
HTTP: http://www.auxio.org/pub/auxio/afinger/



8. REFERENCES
==============================================================================

  1. http://www.perl.com/
  2. http://www.opensource.org/
  3. http://www.cs.wisc.edu/~ballard/bofh/
  4. https://github.com/xinetd-org/xinetd



9. CONTRIBUTORS
==============================================================================

Peter Jones  pjones/pmade.org  FreeBSD support