Ubuntu Manpage: cfingerd - Configurable finger daemon.

Provided by: cfingerd_1.4.3-3.2ubuntu1_amd64

NAME

       cfingerd - Configurable finger daemon.

SYNOPSIS

       cfingerd [ -c | -e | -o | -v ]
                  -c : Check configuration
                  -e : Emulate local finger w/o inetd
                  -o : Turn off all finger queries
                  -v : Request version information

       -c  checks  your installed configuration.  This makes sure there are no existing errors in
       the current cfingerd.conf file.

       -e allows you to emulate a local finger on a user that exists on your system.   This  lets
       you  test  cfingerd  on your system before installing it.  Using the "-e" directive is the
       same as installing the software, typing "finger username@" and getting the output.   Using
       "-e username" does the same.

       -o turns off all finger queries.  This makes it so that no one can finger your system - no
       matter what they try to do.  Unlike the other options, this option is used in  inetd.conf,
       not on the command line.

       -v requests cfingerd version information.

DESCRIPTION

       CFINGERD  is a totally new, and totally configurable finger daemon - one of the first.  It
       listenes on the finger port (port 79) to provide useful information about each  user  that
       is  on  your system according to the finger protocol as described in RFC 1288.  Only thing
       is, cfingerd provides a unique twist.

       CFINGERD  was  designed  for  the  sole  purpose  of  making  output  on  finger   queries
       configurable.  If you want to change any text that is displayed during finger queries, you
       can configure the finger daemon to display just about anything you want.

       CFINGERD also takes into account any security breaches, and attempts to close them.   With
       the  added  bonus  of  creating  ".nofinger"  files,  this  is displayed instead of finger
       information, making it possible for users to keep  themselves  relatively  anonymous  from
       outside  users.   For  a  maximum  of  users  privacy  you  should  place an exact copy of
       /etc/cfingerd/nouser_banner.txt in your .nofinger file.

WHY WAS IT DONE?

       The answer is simple.  Security.  Many sites turn off finger  for  the  reason  that  they
       don't want outside users to see who's on their system, or get information about a specific
       user on their system.  This seemed unfair to the rest of the  users  out  there,  so  this
       program  was  created.   Besides, those sites were waiting for this type of program.  Many
       sites that originally had their finger turned off turned them back on because of cfingerd.

       Many sites have complained that they wanted the ability to create a "fake-user", or a user
       that  doesn't  exist  but  calls a pre-written shell script.  CFINGERD has taken this into
       account,  and  provides  the  best  method  possible  for  creating  such  scripts.   (See
       cfingerd.conf(5) for more information on the configuration file.)

FEATURES CFINGERD PROVIDES, AND DESCRIPTIONS OF EACH

CFINGERD was totally rewritten. Why is this? Well, the older version of cfingerd had
quite a few bugs, and it didn't quite do all of the things that cfingerd now does. This
new version was totally revamped, and most of the bugs that were in the older version of
cfingerd were removed in this one. Besides, the code in here was more compact.

Header and footer displays were a very big part of the original release of cfingerd, and
shall continue to remain in all versions. Headers and footers are only displays at the
beginning and ending of all finger displays, and are used as unique little
"advertisements" or such.

Last time displayed is always a critical issue. It's covered in cfingerd. Cfingerd
simply shows how many times this user is connected, what their idle time is on each TTY
they're connected to, and whether or not they are accepting messages. If they're not
accepting messages, a "[MESG-N]" display will be shown if this is the case. This display
also shows the last time mail was read, and whether or not this user has mail. If this is
still too much for your taste, each of these items can be disabled system wide.

Stand-alone and INETD support is compiled into the program, but only INETD support is
given for the time being. The reason being is that I have not yet added the code for
stand-alone daemon mode.

.nofinger files are used when a user wishes to remain anonymous. These files should be
placed in their home directories, and can display anything they want. There's just a few
restrictions. These .nofinger display files cannot be character devices, directories,
fifos, soft or hard links, or anything else of that caliber. They must only be normal
files.

Fakeusers were supported for the simple fact that many sites want to create users that
don't exist, and make them execute a shell. If you want this done, then install a fake
user. Read up in cfingerd.conf(5) for more information on these useful options.

Service listings were used to show what fakeusers you have installed on your system.
These can be formatted however you wish, and are explained (once again) in
cfingerd.conf(5).

Searching for usernames is a very powerful feature that cfingerd takes full advantage of.
If you are looking for a specific username on the system, or don't know what their name
is, simply use the search.pattern directive with cfingerd will search for all users
containing pattern in their real name or username on that system.

Searching for usernames is NOT case sensitive. You may search for a specific username or
real name, for part of the username or real ame, or for a pattern matching the entire
username or the entire real ame. If you search for part of a user's name, chances are,
it'll be displayed.

Warning searching will currently return the names of daemon users and users

and you will be able to search for a user on your system.

Security is a given. If you don't want to show someone something, then it won't display
what you don't want. Simply edit the cfingerd.conf file and make changes. It's that
simple.

Searching for usernames is NOT case sensitive. If you are searching for a specific
username, or part of the user's name. If you search for part of a user's name or
username, chances are, it'll be displayed.

Not just PLAN, or PROJECT but there's also an option to display your public PGP key, if
you have one. This is very useful if you want to keep your mail or other information
secret to yourself, and don't want "big brother" watching over your shoulder as you talk
amongst yourselves. (Thanks to Andy Smith for this patch). (For your info, the standard
plan file is .plan, project is .project, PGP info is .pgpkey, and XFace icon information
is .xface)

Remember, any or all of these options stated above, can be turned on or off at will. If
you want a specific option turned off, turn it off. :)

FULL LIST OF BUILTIN USER NAMES

cfingerd provides a set of builtin fake users. Two of them are also used internally by
cfingerd.

@ List logged on users without .nofinger file. If the system_list_sites option is
used in the main configuration file cfingerd will try to gather information from
all listed hosts.

userlist@
Same as @, except that it only lists people who are idle no longer than one day.
This is intended to give a better overview of who's really online at the moment of
fingering.

userlist-only@
List logged on users without .nofinger file - without headers and footers. This
fake user is used internally to gather system information from remote hosts for @.

userlist-online@
List logged on users without .nofinger file - without headers and footers. Only
users will be listed who are idle no longer than a day. This fake user is used
internally to gather system information from remote hosts for userlist@.

version@
Display version information for cfingerd.

services@
List all fake users.

search.pattern@
Search for users using the GCOS field in /etc/passwd. Only users will be displayed
who don't have a .nofinger-file.

help@ Help text listing all of these.

These can be disabled in cfingerd.conf(5) as follows

@ and userlist@
Set SYSTEM_LIST to FALSE.

userlist-only@ and userlist-online@
Disable ALLOW_USERLIST_ONLY (i.e. prefix it with a minus sign) or disable
SYSTEM_LIST.

version@
Disable ALLOW_CONFESSION (i.e. prefix it with a minus sign).

services@
Disable ALLOW_FAKEUSER_FINGER (i.e. prefix it with a minus sign).

search.pattern@
Disable ALLOW_SEARCHABLE_FINGER (i.e. prefix it with a minus sign).

help@ Disable ALLOW_CONFESSION (i.e. prefix it with a minus sign).

ERROR MESSAGES

       Any error messages that result are fairly easy to debug if you know what to look for.

       Segmentation Violations don't always occur, but if they ever do,  you  can  pretty  easily
       figure  out  what's going on.  Unfortunately, cfingerd doesn't have any compatibility with
       older cfingerd.conf files, so if you get a Segmentation Violation,  this  (usually)  means
       that your cfingerd.conf file needs to be replaced.

       Timeouts  usually  mean that a script has timed out, or a connection to another site timed
       out.

SYSLOGGING MESSAGES

       Well, there's no real way to describe SYSLOG messages since they can  be  changed  as  the
       system  administrator  chooses.   Although,  examples  can  be given based on the standard
       configuration that was distributed.

       If any IP addresses cannot be matched to a name  it  will  display  a  "IP:  Hostname  not
       matched".

       If the renice fails (to make the program run at the highest priority) then it will display
       "Fatal - Nice died: (reason)".

       If there is no buffer information waiting in the STDIN  buffer,  it  will  display  "STDIN
       contains no data".

       If a trusted host fingers your site, a "<- Trusted" will appear.

       If a rejected host fingers your site, a "<- Rejected" will appear.

       If root is fingered on your site, it will display "Root".

       If a service listing was fingered on your site, it will display "Service listing".

       If a user listing was requested, it will display "User listing".

       If a fake user was requested, it will display "Fake user".

       If  "whois"  data  was  requested,  it will display "Whois request".  (Note, whois was not
       implemented in this release, since it wasn't 'RFC' compliant.)

       Any extra information pertaining to the incoming finger is  displayed  in  the  syslogging
       area.   (It's also recommended that you reconfigure syslog.conf(5) to display to an unused
       VT.  :)

PLANS

       Any other options or improvements will probably come from user suggestions.  :)

       Later plans will make it so that you can define your own display formats  for  the  finger
       display.  This means that you can re-define how you want your finger display to look.

CONTACTING

       If  you like the software, and you want to learn more about the software, or want to see a
       feature   added   to   it   that   isn't   already   here,   then    please    write    to
       cfingerd@infodrom.north.de.         The        project's        webpage        is       at
       http://www.infodrom.north.de/cfingerd/ .