/************************************************************************
 *   IRC - Internet Relay Chat, doc/INSTALL
 *   Copyright (C) 1990,1991,1992, Jeff Trim, Mike Bolotski,
 *   Jarkko Oikarinen and Darren Reed.
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 1, or (at your option)
 *   any later version.
 *
 *   This program 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 General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

            Installing IRC - The Internet Relay Chat Program


Overview of this document:

  1) The config.h file
  2) Editing the Makefile
  3) Compiling IRC
  4) The ircd.conf file


1) Edit the "config.h" file and make changes to the various #DEFINE's:
 
   a) Copy the config.h.dist file to config.h before editing.
  
   b) Define what type of UNIX your machine uses.

      Pick the machine type which best describes your machine and change
      the #undef to #define (if needed).  Some flavours of Unix require no
      #define and in such cases all others should be #undef'd.

   c) DEBUGMODE

	Define DEBUGMODE if you want to see the ircd debugging information
      as the daemon is running. Normally this function will be undefined
      as ircd produces a considerable amount of output.  DEBUGMODE must be
      defined for either of -t or -x command line options to work.
      
   d) DPATH, SPATH, CPATH, MPATH, LPATH, PPATH

        DPATH is provided so that the other pathnames (SPATH, CPATH, etc)
      may be provided in just filename form.  When the server starts, it
      chdir's to DPATH before chroot or any other file operation, making
      it the "current directory" for the server.  This is where core files
      will go if it core dumps.

	Define SPATH to be the directory path to ircd.  This is usually
      /usr/local/bin/ircd, unless you don't have installation permission
      there. 

      Define CPATH to be the directory path to the "irc.conf" file.
      This path is usually /usr/local/lib/irc.conf. The format of this file 
      will be discussed later.

      The LPATH #define should be set to "/dev/null" unless you plan to 
      debug the program.  Note that the logfile grows very quickly.

      Define MPATH to be the path to the 'motd' (message of the day) file
      for the server.  Keep in mind this is displayed whenever anyone
      signs on to your server.

      The PPATH is optional, but if defined, should point to a file which
      either doesn't exist (but is creatable) or a previously used PPATH
      file.  It is used for storing the server's PID so a ps(1) isn't
      necessary.

   e) CHROOTDIR

	To use the CHROOTDIR feature, make sure it is #define'd and that
      the server is being run as root.  The server will chroot to the
      directory name provded by DPATH.

   f) ENABLE_SUMMON, ENABLE_USERS

	For security conscious server admins, they may wish to leave
      ENABLE_USERS undefined, disabling the USERS command which can be used
      to glean information the same as finger can.  ENABLE_SUMMON toggles
      whether the server will attempt to summon local users to irc by
      writing a message similar to that from talk(1) to a user's tty.

   g) SHOW_INVISIBLE_LUSERS, NO_DEFAULT_INVISIBLE

	On large IRC networks, the number of invisible users is likely to
      be large and reporting that number cause no pain.  To aid and effect
      this, SHOW_INVISIBLE_LUSERS is provided to cause the LUSERS command
      to report the number of invisible users to all people and not just
      operators.  The NO_DEFAULT_INVISIBLE define is used to toggle whether
      clients are automatically made invisible when they register.

   h) OPER_KILL, OPER_REHASH, OPER_RESTART, LOCAL_KILL_ONLY

	The three operator only commands, KILL, REHASH and RESTART, may all
      be disabled to ensure that an operator who does not have the correct
      privilidges does not have the power to cause untoward things to occur.
      To further curb the actions of guest operators, LOCAL_KILL_ONLY can
      be defined to only allow locally connected clients to be KILLed.

   i) The rest of the user changable #define's should be pretty much self
      explanatory in the config.h file.  It is *NOT* recommended that any
      of the file undef the line with "STOP STOP" in it be changed.

3) Configure and compile the code.

      Edit the root Makefile for the server, uncomment/comment the correct
   CFLAGS/IRCDLIBS lines as appropriate for your system.
      Change DESTDIR to be the same as the path for DPATH in config.h.
   Type "make". This will compile the server, the client, and the services.
   At the end of this step, the server directory will contain 'ircd',
   and the client directory will contain 'irc'.  To get the server installed,
   type "make install" which will build a default m4 file for preprocessing,
   copy example.conf and put the server all in DESTDIR.  The irc client and
   a copy of the server will also be placed in BINDIR and the modes set
   accordingly.

4) The ircd.conf file.

   After installing the ircd and irc programs, edit the irc.conf file
   as per the instructions in this section and  install it in the 
   location you specified in the config.h file.  There is a sample
   conf file called example.conf in the /doc directory.

   Appendix A describes the differences between IP addresses and host
   names.  If you are unfamiliar with this, you should probably scan 
   through it before proceeding.

   The irc.conf file contains various records that specify configuration
   options.  The record types are as follows:
   
   1.  Server connections   	(C,N)
   2.  Machine information	(M)
   3.  Client connections	(I)
   4.  Default local server	(U)
   5.  Operator priviliges	(O)
   6.  Administrative info	(A)
   7.  Excluded accounts	(K)
   8.  Excluded machines        (Q)
   9.  Connection Classes       (Y)
  10.  Leaf connections         (L)
  11.  Service connections      (S)
  12.  Port connections		(P)
  13.  Hub connections		(H)


   1. SERVER CONNECTIONS:  How to connect to other servers
			   How other servers can connect to you

   WARNING:
     The hostnames used as examples are really only examples and
     not meant to be used (simply because they don't work) in real life.

   Now you must decide WHICH hosts you want to connect to and WHAT ORDER you
   want to connect to them in.  For my example let us assume I am on the
   machine "rieska.oulu.fi" and I want to connect to irc daemons on 3 other
   machines:

         "garfield.mit.edu"        - Tertiary Connection
         "irc.nada.kth.se"         - Secondary Connection
         "nic.funet.fi"            - Primary Connection

   And I prefer to connect to them in that order, meaning I first want to
   try connecting to "nic.funet.fi", then to "irc.nada.kth.edu", and
   finally to "garfield.mit.edu".  So if "nic.funet.fi" is down or
   unreachable, the program will try to connect to "irc.nada.kth.se".
   If irc.nada.kth.se is down it will try to connect to garfield and so forth.
   PLEASE limit the number of hosts you will attempt to connect to down to 3.
   This is because of two main reasons:
     a) to save your server from causing extra load and delays
        to users
     b) to save internet from extra network traffic
        (remember the old rwho program with traffic problems when
        the number of machines increased).

   The format for the CONNECT entry in the "irc.conf" is:

       C:<TARGET Host Addr>:<Password>:<TARGET Host NAME>:<TARGET Host PORT>
Field: 1        2              3                4               5

   for example:
   
    C:nic.funet.fi:passwd:nic.funet.fi:6667 

          - or -

    C:128.214.6.100:passwd:nic.funet.fi:6667

          - or -

    C:root@nic.funet.fi:passwd:nic.funet.fi:6667


    Explanation:

    Each field is separated with a ":" charcter:

    Field 1: Field 1 tells the IRC program which option is being configured.
             "C" corresponds to a server Connect option.

    Field 2: Specifies the host name or IP address of the machine to connect
	     to.  If "user@" prefixes the actual hostname or IP address
	     the server will require that the remote username returned by
	     the ident server be the same as the one given before the "@".

    Field 3: The password of the other host.  A password must always be
	     present for the line to be recognized.

    Field 4: The full hostname of the target machine. This is the name that 
	     the TARGET server will identify itself with when you connect 
	     to it.  If you were connecting to nic.funet.fi you would receive
	     "nic.funet.fi" and that is what you should place in 
	     this field.
  
    Field 5: The INTERNET Port that you want to connect to on the TARGET 
	     machine. Most of the time this will be set to "6667".  
             If this field is left blank, then no connections will 
             be attempted to the TARGET host, and your host will accept
             connections FROM the TARGET host instead.

   Some examples:

            C:nic.funet.fi::nic.funet.fi:6667
 
            This reads: Connect to host "nic.funet.fi", with no password
            and expect this server to identify itself to you as
            "nic.funet.fi". Your machine will connect to this host to
            PORT 6667.

            C:18.72.0.252:Jeff:garfield.mit.edu:6667

            This reads: Connect to a host at address "18.72.0.252", using a
            password of "Jeff".  The TARGET server should identify
            itself as "garfield.mit.edu".  You will connect to Internet
            Port 6667 on this host.

            C:irc.nada.kth.se::irc.nada.kth.se

            This reads: do not attempt to connect to "irc.nada.kth.se",
			but if "irc.nada.kth.se" requests a connection,
			allow it to connect.

   Now back to our original problem, we wanted OUR server CONNECT to 3
   hosts,  "nic.funet.fi", "irc.nada.kth.se" and "garfield.mit.edu" in
   that order.  So as we enter these entries into the file they must be
   done in REVERSE order of how we could want to connect to them.

   Here's how it would look if we connected "nic.funet.fi" first:

	C:garfield.mit.edu::garfield.mit.edu:6667
	C:irc.nada.kth.se::irc.nada.kth.se:6667
	C:nic.funet.fi::nic.funet.fi:6667

   Ircd will attempt to connect to nic.funet.fi first, then to irc.nada
   and finally to garfield.

   Reciprocal entries:

   Each "C" entry requires a corresponding 'N' entry that specifies
   connection priviliges to other hosts.  The 'N' entry contains
   the password, if any, that you require other hosts to have before
   they can connect to you.  These entries are of the same format as
   the "C" entries.
    
   Let us assume that "garfield.mit.edu" connects to your server
   and you want to place password authorization authorization on garfield.
   The "N" entry would be:
   
          N:garfield.mit.edu:golden:garfield.mit.edu
  
   This line says: expect a connection from host "garfield.mit.edu",
   and expect a login password of "golden" 
   and expect the host to identify itself as "garfield.mit.edu".
     
	  N:18.72.0.252::garfield.mit.edu

   This line says: expect a Connection from host "18.72.0.252", and 
   don't expect login password.  The connecting host should identify itself
   as "garfield.mit.edu". 

  
   Wildcards domains: 
	To reduce the great amount of servers in IRCnet wildcard
	DOMAINS were introduced in 2.6. To explain the usage of
	wildcard domains we take an example of such:
		*.de  - a domain name matching all machines
                        in Germany.
        Wildcard domains are useful in that ALL SERVERS in Germany
        (or any other domain area) can be shown as one to the
	rest of the world. Imagine 100 servers in Germany, it
	would be incredible waste of netwotk bandwidth to broadcast
	all of them to all servers around the world.

	So wildcard domains are a great help, but how to use them ?
	They can be defined in the N-line for a given connection,
	in place of port number you write a magic number called
	wildcard count.

	Wildcard count tells you HOW MANY PARTS of your server's name
	should be replaced by a wildcard. For example, your server's
	name is "tolsun.oulu.fi" and you want to represent it as
	"*.oulu.fi" to "nic.funet.fi". In this case the wildcard count
	is 1, because only one word (tolsun) is replaced by a wildcard.
	If the wildcard count would be 2, then the wildcard domain would
	be "*.fi". Note that with wildcard name "*.fi" you could NOT
	connect to "nic.funet.fi", because that would result in a server
	name COLLISION (*.fi matches nic.funet.fi).

	I advice you to not to use wildcard servers before you know
	for sure how they are used, they are mostly beneficial for
	backbones of countries and other large areas with common domain.


   2. MACHINE INFORMATION
                            
   IRC needs to know a few things about your UNIX site, and the "M" command
   specifies this information for IRC.  The fomat of this command is:

           M:<YOUR Host NAME>:xxx:<Geographic Location>:<Internet Port>
   Field:  1         2         3           4                 5

   Explanation:

      Field 1: "M" specifies a Machine description line

      Field 2: The name of YOUR host adding any Internet DOMAINNAME that 
               might also be present.  

      Field 3: -- NOT USED --: Set to Value NULL (No spaces at ALL!).
    
      Field 4: Geographic Location is used to say WHERE YOUR SEVRER is,
               and gives people in other parts of the world a good
               idea of where you are!  If your server is in the USA, it is
               usually best to say: <CITY> <STATE>, USA.  Like for Denver
               I say: "Denver Colorado, USA".  Finnish sites (like
               tolsun.oulu.fi generally say something like "Oulu, Finland".
 
      Field 5: The Internet port your server will use.  Should be set to
	       the same value as in the config.h file.


      Example:
                M:tolsun.oulu.fi::Oulu, Finland:6667

                This line reads: My Host's name is "tolsun.oulu.fi" and
                my site is located in "Oulu, Finland".  My ircd will use
		Internet Port 6667.


                M:orion.cair.du.edu::Denver Colorado, USA:6667

                This line reads: My Hosts name is "orion.cair.du.edu"
                and my site is located in "Denver Colorado, USA".
	        I have defined Internet Port number "6667" to be used
                as my IRCD Socket Port.


   3. CLIENT CONNECTIONS -   How to let clients connect to your IRCD.

   A client is a program that connects to the ircd daemon (ircd).  Currently
   there are clients written in C and in GNU Emacs Lisp.  The "irc"
   program is the C client.  Each person that talks via IRC is running
   their own client.

   The irc.conf files contains entries that specify which clients are allowed
   to connect to your irc daemon.  Obviously you want to allow your cwn
   machine's clients to connect.  You may want to allow clients from 
   other sites to connect.  These remote clients will use your server
   as a connection point.  All messages sent by these clients will pass
   through your machine.

   The format of this entry in the conf file is:

          I:<TARGET Host Addr>:<Password>:<TARGET Hosts NAME>:<Internet Port>
    Field:1         2               3             4                5


      For example, if you were installing IRC on tolsun.oulu.fi and you wanted
      to allow examples sake let us assume you were making this file for
      tolsun and you wanted to let your own clients to connect to your
      server, you would add this entry to the file:

      I:128.214.5.6::tolsun.oulu.fi
      or
      I:tolsun.oulu.fi::tolsun.oulu.fi

      If you wanted to let remote clients connect, you could add the
      following lines:

      I:*.du.edu::*.du.edu

      Allow any clients from machines whose names end in "du.edu" to connect
      with no password.

      I:128.214.6.100::nic.funet.fi

      Allow clients from a machine with that IP number and the name 
      nic.funet.fi to connect.

      I:*.tut.fi:secret:*.tut.fi

      Allow clients from machines matching *.tut.fi to connect
      with the password 'secret'.

      I:*::*

      Allow anyone from anywhere to connect your server.
      This is the easiest way, but it also allows people to for example
      dump files to your server, or connect 1000 (or how many open
      sockets per process your OS allows) clients to your machine
      and take your network ports. Of course the same things can be
      done by simply telnetting to your machine's SMTP port (for example).

   NEW!!!
      As of the 2.7.2d version of the server, the server is able to accept
      connections on multiple ports. I-lines are required for each P-line
      to allow connections to be accepted. For unix sockets, this means
      either adding I:/path/port::/path/port or some variation (wildcards
      are recognised here). For internet ports, there must be an I-line
      which allows the host access as normal, but the port field of the
      I-line must match that of the port of the socket accepting the
      connectiion. A port number of 0 is a wildcard (matches all ports).

   4. DEFAULT HOSTS (for local clients)

      This defines the default connection for the irc client.  If you are
      running an ircd server on the same machine, you will want to define
      this command to connect to your own host.  If your site is not running
      a server then this command should contain the TARGET host's connection
      information and password (if any).  The format for this command is:

         U:<TARGET Host addr>:<Password>:<TARGET Host NAME>:<Internet Port>
  Field: 1         2              3                4            5
   

      For example:

           U:tolsun.oulu.fi::tolsun.oulu.fi:6667
           U:128.214.5.6::tolsun.oulu.fi:6667
           U:tolsun.oulu.fi::tolsun.oulu.fi

      If the port number is omitted, irc will default to using 6667.

  5. OPERATOR Privileges:  How to become the IRC administrator on your site

   To become an IRC Administrator, IRC must know who is authorized to become
   an operator and what their "Nickname" and "Password" is.  To add this
   information, EDIT your "irc.conf" file and add the following command
   line to it:

          O:<TARGET Host NAME>:<password>:<nickname>
  Field:  1          2             3          4

  Explanation:
 
     Field 1: Speficies Operator record. If you use capital letter ('O')
              in it, it specifies a global operator. Small letter ('o')
              specifies a local operator. Local operator has basically the
              same rights except global operator with some restrictions.
 
     Field 2: Tells IRC which host you have the privileges FROM.  This
              means that you should be logged into this host when you
              ask for the priviliges.  If you specify "tolsun.oulu.fi"
              then IRC will expect your CLIENT to be connected at 
              "tolsun.oulu.fi" - when you ask for OPERATOR privileges
              from "tolsun.oulu.fi".  You cannot be logged in at any
              other host and be able to use your OPERATOR privileges
              at tolsun, only when you are connected at TOLSUN will this
              work - this is a safeguard against unauthorized sites.


     Field 3: If your AUTHORIZATION Password - this is the password that 
              let's IRC know you are who you say you are!  Never tell anyone
              your password and always keep the "irc.conf" file protected
              from all of the other users.
 
     Field 4: The Nickname you usually go by - but you can make this what
              you want.  It is better to make this a NICKNAME that no one
              else knows, but anything will do.  I usually use my own
              loginname.

  Example:
              O:orion.cair.du.edu:pyunxc:Jeff

              There is an OPERATOR at "orion.cair.du.edu" that can get
              Operator priviliges if he specifies a password of "pyunxc"
              and uses a NICKNAME of "Jeff".



  6. ADMINISTRATIVE INFORMATION

  The "A" command is used for administrative information about a site.
  The e-mail address of the person running the server should be included
  here in case problems arise.

  
            A:<Your Name/Location>:<Your Electronic Mailing Addr>:<other> 
  Field:    1        2                    3                         4

  Explanation:

       Field 1: "A" specifies an Admin record.


       Field 2: Use this field to say tell your FULL NAME and where in the 
                world your machine is.  Be sure to add your City, 
		State/Province and Country.


       Field 3: Use this field to specify your Electronic Mailing Address
                preferably your Internet Mailing Address.  If you have
                a UUCP or ARAPnet address - please add that as well.  Be
                sure to add any extra DOMAIN information that is needed,
                for example "mail jtrim@orion" probably won't work as a 
                mail address to me if you happen to be in Alaska.  But 
                "mail jtrim@orion.cair.du.edu" would work because you 
                know that "orion" is part of the DOMAIN "cair.du.edu". 
                So be sure to add your DOMAINNAMES to your mailing addresses.

       Field 4: Is really an OTHER field - you can add what you want here,
                

  Examples (the line is just one line in the confuration file, here it
            is cut into two lines to make it clearer to read):

A:Jeff Trim -  Denver Colorado, USA:INET jtrim@orion.cair.du.edu UUCP {hao,
isis}!udenva!jtrim:Terve! Heippa!  Have you said hello in Finnish today?;)

  Would look like this when printed out with the /admin command:

      Jeff Trim -  Denver Colorado, USA
      INET jtrim@orion.cair.du.edu   UUCP {hao,isis}!udenva!jtrim
      Terve! Hei! Heippa!  Have you said hello in Finnish today? ;)
 
 
  Note that the A record cannot be split across multiple lines; it will 
  typically be longer than 80 characters and will therefore wrap around
  the screen.


  7. REMOVING A USER FROM IRC  Remove an errant user from IRC on your site.

  Obviously it is hoped that you wouldn't have to use this command.
  Unfortunately sometimes a user can become unmanageable and this is your
  only recourse - the KILL USER command.  THIS COMMAND ONLY AFFECTS YOUR
  SERVER - If this user can connect to another SERVER somewhere else in
  the IRC-Network then you would have to talk to the administrator on that
  site to disable his access from that IRCD Server as well.

  The format of this command is:

         K:<Host Name>:<time interval(s)>:<User>
  Field: 1     2               3            4

  Explanation:

       Field 1:  "K" tells the IRCD that you are making a KILL USER command
                 entry.

       Field 2:  In this field you specify the Hostname that the user is 
                 connecting from.  If you wanted to REMOVE connects
                 to IRC from "orion.cair.du.edu" then you would want to enter
                 "orion.cair.du.edu".  If you want to REMOVE ALL HOSTS
                 access you can use '*' (Wild Card notation) and no matter
                 what host the USERNAME (specified in Field 4) connects from
                 s/he will be denied access. Removing all hosts isn't
                 very smart thing to do though, why would you run an ircd
                 if you allow nobody to connect to it anyways ?

       Field 3:  Either leave this field empty (no spaces), then then lines
		 is active continuously for the specified user/host machine.
		 You may also specify intervals during the line should be
		 active, see examples above.
    
       Field 4:  The USERNAME of the user you want removed from IRC.  For
                 example 'root'.

   
   Some Examples:
                   K:orion.cair.du.edu::jtrim
 
               If user 'jtrim' connects to IRC from host "orion.cair.du.edu"
               then IMMEDIATELY REMOVE HIM from my IRCD.

                   K:*.cair.du.edu::root

               If user 'root' connects to IRC from any host that has the 
               suffix "cair.du.edu" - then IMMEDIATELY REMOVE THEM from
               my IRCD.

                   K:*::vijay

               This line reads "I don't care WHAT HOST user 'vijay' is on,
               I will NEVER allow username 'vijay' to login to my IRCD.

	           K:*.oulu.fi:0800-1200,1400-1900:*

	       This disallows all users from hosts with enddomain 'oulu.fi'
	       access to your server between 8 and 12am, 2 and 7pm.
	       Users get kicked off if they're already signed on when the
	       line becomes active (they'll get a warning 5 minutes ago).

  8. Disallowing SERVERS in your irc net.

   In some cases people run into difficulties in net administration.
   For one reason or another you do not want a certain server to be
   in your net (for example because of the security holes it opens
   for every server if it's not secured carefully). In that case
   you should use Q-lines in your server. When you specify a server
   name in Q-line, everytime some server link tries to introduce you
   a server (remember, all server names are broadcast around the net),
   that name is checked if it matches the Q-lines in your server.
   If it matches, then your server disconnects the link. Note that
   just placing Q-lines to your server probably results in your server
   being left alone, unless other servers have agreed to have the
   same Q-line in their ircd configuration files as well.

   Example:
                Q::of the security holes:foo.bar.baz

   This command excludes a server named "foo.bar.baz", the reason
   is given to be security holes (you should give a reason, it is
   polite). The first field is unused, so leave it empty.

 9. Connection Classes.

   To enable more efficient use of MAXIMUM_LINKS, connection classes
   were implemented. To give a connection a class, add another field
   (a sixth) to the C/N lines for a particular server.
   Each line for a server should have the same number as the sixth
   field.  If it is absent, the server deaults it to 0, using the
   defaults from the config.h file.  To define a connection class,
   you need to include a Y: line in the irc.conf file.  This enables
   you to define the ping frequency, connection frequency and maximum
   number of links that class should have.  Currently, the Y: line MUST
   appear in the irc.conf file BEFORE it is used in any other way.

   The format for the line is:

       Y:<CLASS>:<PING FREQUENCY>:<CONNECT FREQUENCY>:<MAX LINKS>:<SENDQ>
Field: 1    2                3                4                5     6

   Field 2:  This is the class number which gains the following attributes
   and should match that which is on the end of the C/N line.

   Field 3:  This field defines how long the server will let the connection
   remain "silent" before sending a PING message to make sure it is still
   alive.  Unless you are sure of what you are doing, use the default value
   which is in your config.h file.

   Field 4:  By changing this number, you change how often your server
   checks to see if it can connect to this server.  If you want to check
   very occasionally, use a large value, but if it is an important
   connection, you might want a smaller value so that you connect to it
   as soon as possible.

   Field 5:  This field defines the maximum number of links this class
   will allow from automatic connections.  Using /CONNECT overrides this
   feature.

   Field 6:  This field defines the 'sendq' value for this class.  If this
   field is not present, the default (from config.h) is assigned.

   NOTE: leaving any of the fields out means their value is 0 (ZERO)!!

   example:

   Y:23:120:300:5

   define class 23 to allow 5 auto-connections, which are checked every
   300 seconds.  The connection is allowed to remain silent for 120
   seconds before a PING is sent.  NOTE: fields 3 & 4 are in seconds.

   You may also give I lines a class (again the sixth field to define
   which class).  This is only usefull (currently) for redefining the
   ping frequency.  It can also be useful as a diagnostic to see how
   much each I line is used when combined with the TRACE output.

   Another feature of connection class is the ability to do automatic
   routing by using the class as a 'priority'.  If you are connected
   to a server which has a class lower than one of the servers that is
   'behind' it, the server will disconnect the lower class one and
   schedule a 'new' connection for the higher class server.

 10. Leaf Connections.

   To stop servers which should only act as leaves from hubs becoming
   hubs accidently, the L line was introduced so that hubs can be aware
   of which servers should and shouldnt be treated as leaves. A leaf
   server is supposed to remain a node for the entirity of its life
   whilst connected to the IRC server network.  It is quite easy, however
   for a leaf server to be incorrectly setup and create problems by
   becoming a node of 2 or more servers, ending its life as a leaf. The
   L line enables the administrator of an IRC 'Hub server' to 'stop' a
   server which is meant to act as a leaf trying to make itself a hub.
   If, for example, the leaf server connects to another server which doesnt
   have an L-line for it, the one which does will drop the connection, once
   again making the server a leaf.

       L:<SERVER MASK>:*:<SERVER NAME>:<MAX DEPTH>
Field: 1       2       3       4            5

   Field 2 is a mask of which servers the leaf-like attributes are used on
   when the server receives SERVER messages.  The wildcards * and ? may be
   used within this field for matching purposes.  If this field is empty,
   it acts the same as if it were a single * (ie matches everything).

   Field 4 is the the server connectted to you that for which you want to
   enforce leaf-like attributes upon.

   Field 5 is the maximum depth allowed on that leaf and if not specified,
   a value of 1 is assumed.  The depth is checked each time a SERVER message
   is received by the server, the hops to the server being the field checked
   against this max depth and if greater, the connection to the server that
   made its leaf too deep has its connection dropped.
   For the L-line to come into effect, both fields, 2 and 4, must match up
   with the new server being introduced and the server which is responsible
   for introducing this new server.

 11. Service Connections (Not yet implemented)

  Introduction.
   The Service is a special kind of IRC client. It does not have the full
   abilities of a normal user but can behave in a more active manner than
   a normal client. Services as they stand now are not fully implemented.
   The following line can be added to your ircd.conf file to enable a
   service:
  
          S:<TARGET Host Mask>:<password>:<service_name>
  Field:  1          2             3          4

  Explanation:

    Field 2:
	The host mask should be set to match the hosts(s) from which the
	service will be connecting from. This may be either an IP# or full
	name (prefered).

   Field 3:
	This is the password which must be passed in the SERVICE command.
 
   Field 4:
	The 'service name' is only used for the purpose of finding the
	right S-line from the ircd.conf file for password matching. The
	actual service name used is that set by NICK commands prior to
	SERVICE being sent.

   To connect a service to your server, you must first create an S-line
   entry in your ircd.conf file and get your server to read this in (ie
   rehash or reboot). Once your server has updated itself, you can then
   attempt to register your connection as a service.
   Registering as a service is similar to registering as a normal user
   except that you must send NICK first and then SERVICE. The service
   command should look something like this:

	SERVICE secretpassword referencename :Service information

   A successfull registering of a service at the server will result in
   a RPL_YOURESERVICE (383) being sent back to you. Any other reply as
   a result of sending service indicates an error has occured.

   A service is not a very useful sort of client, it cannot join channels
   or issue certain commands although most are available to it. Services,
   however, are not affected by flood control. It is therefore wise to
   oversee the use of S-lines with some care.

 12. Port Connections

  Introduction.
   The port line adds flexibility to the server's ability to accept
   connections. By use of this line in the ircd.conf file, it is easy
   to setup both Unix Domain ports for the server to accept connections
   on as well as extra internet ports.

       P:<Internet IP# Mask>:<*>:<*>:<PORT>
Field: 1        2             3   4     5

or

       P:<Directory>:<*>:<*>:<PORT>
Field: 1        2             3   4     5

  Explanation
   Internet Ports
    Field 1
	The internet IP mask defines where connections may come from and
	be accepted. The IP mask uses either *'s or 0's as wildcards. The
	following two lines are the same:

		P:128.2.*:::6664
		P:128.2.0.0:::6664

	The incoming isnt matched against the mask, rather the ip# string
	is decoded and compared segment by segment. Thus
		P:128.2*.1.2:::6664
	will not match 128.20.1.2.

     Field 5
	The port number field tells the server which port number it should
	listen on for incoming connections.

    Unix Socket Ports.
     Field 1
	The path set in field 1 should be the directory name in which to
	create the unix socket for later listening to. The server will
	attempt to create the directory before creating the unix socket.

     Field 5
	The port field when used in combination with a pathname in a P-line
	is the filename created in the directory set in Field 1.

     Example:
		P:/tmp/.ircd:::6667

	Creates a unix socket in the /tmp/.ircd directory called "6667".
	The unix socket (file) must be a numerical.

13.  Hub Connections

      In direct contrast to L-lines, the server also implements H-lines to
   determine which servers may act as a hub and what they may 'hub for'.
   If a server is only going to supply its own name (ie act as a solitary
   leaf) then no H-line is required for, else a H-line must be added as
   follows:

       H:<SERVER MASK>:*:<SERVER NAME>
Field: 1       2       3       4

   Explanation:
    Field 2
      All servers that are allowed via this H-line must match the mask
      given in this field.

    Field 4
      This field is used to match exactly against a server name, wildcards
      being treated as literal characters.

   Examples:

		H:*.edu:*:*.bu.edu

	Allows a server named "*.bu.edu" to introduce only servers that
 	match the "*.edu" name mask.

		H:*:*:eff.org

	Allow "eff.org" to introduce (and act as a hub for) any server.

   Note:  It is possible to have and use multiple H-lines (or L-lines) for
	  the one server.  eg:

		H:*.edu:*:*.bu.edu
		H:*.au:*:*.bu.edu

	   is allowed as is

		L:*.edu:*:*.au
		L:*.com:*:*.au


Appendix A: Difference between IP addresses and hostnames


   There are 2 different types of INTERNET addresses, NAME addresses and
   NUMERIC addresses.  NAME addresses look like ENGLISH words (and indeed
   they are ENGLISH words that refer to a given host).  A NAME address looks
   like "tolsun.oulu.fi" - and that particular address refers to the machine 
   named TOLSUN in Finland.  It is a UNIQUE address because no other machine
   in the world has its NAME address the same as "tolsun.oulu.fi".  Anytime
   you say "telnet tolsun.oulu.fi" - you would always connect to TOLSUN in
   Finland.  NUMERIC addresses refer to those addresses that are made up of
   NUMBERS for example "128.214.5.6" is the NUMERIC address for TOLSUN.  This
   address is also UNIQUE in that no other machine in the world will be use 
   those NUMERIC numbers.  The NUMERIC address is usually more reliable than
   the NAME address because not all sites can recognize and translate the
   NAME address into it's numeric counterpart.  NUMERIC always seems to work
   best, but use a NAME address when you can because it is easier to tell
   what host you are connected to.


   Every Unix machine has a file called "/etc/hosts" on it.  This file 
   contains NAME and NUMERIC addresses.  When you supply IRC with a NAME 
   address it will at first try to find it in /etc/hosts, and then (if it's 
   really smart), use the local Domain Name Server (DNS) to find the NUMERIC
   address for the host you want to connect to.  Thus if you plan to use NAME
   addresses keep in mind that on SOME sites the entry for the TARGET machine
   must be found in /etc/hosts or the NAME address will fail.  A typical 
   entry in /etc/hosts looks like this:

   130.253.1.15    orion.cair.du.edu orion.du.edu orion    # BSD 4.3

   This particular example is the Host ORION at the University of Denver. 
   Notice that on the far left is the NUMERIC Address for orion.  The
   next few ENGLISH words are the NAME addresses that can be used for orion,
   "orion.cair.du.edu", "orion.du.edu", "orion".  ALL of these NAME addresses
   will return the NUMERIC address "130.253.1.15" which IRC will use to
   connect to the TARGET UNIX. (when I say TARGET UNIX I am refering to the
   UNIX you want to connect to for IRC). Any futher questions about
   /etc/hosts should be directed to "man hosts".


Appendix B: Enabling Summon Messages

   +-----------------------------------------------------------------------+
   |            E N A B L I N G    / S U M M O N    M E S S A G E S        |
   +-----------------------------------------------------------------------+

   *NOTE* You must have ROOT or special access to the GROUP tty ('/dev')
   to do this. If you want to allow users around the world to summon
   users at your site to irc, then you should make sure that summon works.

   The "IRCD" program needs access to the GROUP of '/dev'.   This
   directory is where user TTY's are stored (as UNIX treats each Terminal
   as a FILE!)   IRCD needs GROUP ACCESS to /dev so that users can be
   SUMMONED to the program by others users that are *in* the program.
   This allows people from other Universities around the world to SUMMON
   your users to IRC so that they can chat with them.  Berkeley, SUN, HP-UX
   and most of the newer versions of UNIX check to see if a USER is
   accepting MESSAGES via the GROUP access rights on their TTY listing
   in the /dev directory. For example an entry in '/dev' looks like this:

  (Unix Path on BSD 4.3 UNIX is:  /dev/ttyp0)

        crw------- 1 jtrim     20,     0 Apr 29 10:35 ttyp0

   You will note that 'jtrim' OWNS this terminal and can READ/WRITE to this
   terminal as well (which makes sense because I am ENTERING DATA and
   RECEIVEING DATA back from the UNIX).  I logged into this particular
   UNIX on "April 29th" at "10:35am" and my TTY is "ttyp0".  But further
   of *note* is that I do not have my MESSAGES ON! (mesg n)  -- This is
   how my terminal would look with MESSAGES ON (mesg y):

        crw--w---- 1 jtrim     20,     0 Apr 29 10:35 ttyp0

   With my MESSAGES ON (mesg y) I can receive TALK(1) requests, use the 
   UNIX WRITE(1) command and other commands that allow users to talk
   to one another.  In IRC this would also allow me to get IRC /SUMMON
   messages.  To set up the "IRCD" program to work with /SUMMON type
   the following:  (using ROOT or an account that has access to '/dev').

       % chgrp tty ircd
       % chmod 6111 ircd 

   The above commands read: "Give IRCD access to GROUP tty (which is /dev)
   and then when ANYONE runs the IRCD allow SETUID and SETGID priviliges
   so that they can use the /SUMMON command.
