Major changes between version 0.13 and 0.14.
--------------------------------------------
* Added code to use the new kernel interface for packet forwarding
  in kernels after 1.3.75. If you are using a version of diald compiled
  with kernel includes from an earlier kernel, you will have to recompile
  diald to activate this code. Sorry, the kernel interface has changed
  and I need the more recent include files from the kernel to get
  things right for the current 1.3.X kernels. This means I can't
  avoid the need to recompile diald unless I decide to put one of the
  include files from 1.3.X into the diald distribution.
  [Versions of diald compiled under kernels > 1.3.75 seem to work
   fine on 1.2.13 kernels (for those people who run both bleeding
   edge and stable kernels on their systems.)]

* Added in code to deal with the possibility of pppd shutting down
  the network layer without shutting down the link. This should
  not happen normally. In fact if it is happening, then it probably
  indicates a problem with pppd, or your service providers ppp
  implementation. This is just in case code. If the link layer
  dies diald will notice, issue an error message, and wait for
  it come back up. If it does not come back after 60 seconds it will
  kill pppd.

* Added in support for multiple simultaneous monitor outputs.

* Minor changes so that diald doesn't become a CPU hog on linux-1.3.81
  and later kernels. The problem was a change in the sematics of
  select() on named pipes.

* Fixed a bug that caused diald to go into an infinite loop if
  there were no free devices available.

* Added in code to attempt automatic MTU adjustments when PPP
  negotiates an MTU that does not match the request. This issues
  a warning message in the system logs since it is not really
  supported by the kernel. The main reason for this code is to
  make it clear to the user that the MTU needs to be changed
  by issuing a really noisy error message.

Major changes between version 0.12 and 0.13.
--------------------------------------------

* The directory structure of the distribution has changed a little.
  There are now several subdirectories:

  bin		- distributed scripts.
  contrib	- contributed utilities.
  config	- distributed configuration files.
  doc		- documentation for diald.
  patches	- patches for other software that may be needed
		  be diald is being used.

* Removed the direct use of <asm/byteorder.h> so that diald can 
  be compiled on older systems (e.g. linux-1.59) that don't define this.

* Magic to get rid of the need to define PPP_VERSION_2_2_0 (or not).
  Diald no longer needs to know which version is compiled into
  the kernel.

* Fixed a bug in the implementation of the "reroute" option.

* Added an option to implement logarithmic backoff on the
  timeout for redialing attempts. See "redial-backoff-start"
  and "redial-backoff-limit" in the manual page.

* Added an option to limit the number of consecutive failed
  attempts to make a connection that diald will allow. When
  the limit is exceeded diald will block further connections
  until an "unblock" command is issued on the command FIFO.
  This is intended to prevent diald from going nuts at an
  unattended site and ringing up a giant phone bill
  when the maching on the other end of the modem is just
  answering and doing nothing.

* Fixed a minor problem on the manual page where it said that proxyarp
  could not be done directly by diald. It can now.

* Fixed a bug where proxyarp.c would not compile with pppd-2.1.2d on
  the system.

* Fixed it so that the ip-down script only gets run if the interface
  was actually up. It used to get run if diald attemped to dial out and
  failed.

* Fixed spurious error messages about various commands failing.
  This was due to a bad interaction between diald's signal handling
  and the libc implementation of system(). Diald no longer uses
  the libc system() call.

* Added metrics to the routes generated by diald. This won't
  cause any changes on machines running 1.2.x kernels, but
  it fixes a problem on 1.3.x kernels that can cause TCP
  connections to get killed if a packet retransmit happens
  to occur between the time a link gets trashed and diald manages
  to put the route to the proxy link back into place.
  Note that this means there is now an extra parameter passed
  to the "addroute" and "delroute" commands. See the manual
  page for information on correctly using this information.

* Added output for load information to the monitor information.
  Changed dctrl to use this information.

* Added a "dynamic" command to the FIFO commands. This command
  takes two parameters, giving a local and a remote ip address.
  It is intended for use with connect scripts that do some extra
  work to figure out the dynamic ip addresses, so they can
  pass that information back to diald. This will be most
  useful to you if you must parse out the IP addresses and
  then still issue a further command as part of your login sequence.
  (Cases like this cannot be handled by the "dslip-mode" option).

* Added a "message" command to the FIFO commands. This
  just passes its input on as the output to the monitor
  "messages" segment. It is intended to let connect scripts
  send messages to the monitoring process for diald.
  This allows connect scripts that inform the user of
  progress and error conditions as part of the monitoring information.

* Added output for "messages" to the monitor information.
  See above for the "messages" FIFO command.

* Added in a give-way option and better support
  for the "two-way" operation mode. Diald will now always
  allow an incoming connection, provided its outgoing link is
  down, or it is in the process of closing its outgoing link.
  If the "give-way" option is set, diald will allow an incoming
  connection to be attempted, unless the link is currently up.
  If diald is in the middle of a connection when the incoming 
  request occurs, and "give-way" is set, it will abandon the
  outgoing connection in favour of the incoming one.
  Thanks to Oliver Jowett <oliver@sa-search.massey.ac.nz> for
  providing the patches that implement these features.

* Fixed the parsing of configuration files to deal with
  quoted characters the same way that pppd does.
  Also, added in quotes delimited by ' rather than ".

* Lots of updates to the documentation.

Major changes between version 0.11 and 0.12.
--------------------------------------------

* Completely rewrote the dctrl tool. This is the tk equivalent
  of Gavin Hurlbut's <gjhurlbu@beirdo.uplink.on.ca> diald-top
  package (an excelent tool that I recomend to you all).
  Anyway, dctrl now has a cool graphical indicator to show the
  state of your link in its icon. You can also issue any
  of the FIFO commands directly to diald using dctrl, and
  you can watch the state of your connection queue in a nice
  scrollable graphic window.
  Sorry, there's no manual page. Just run it It should
  be obvious how to use it.
  NOTE: You may want to edit the configurable parameters
  at the start of the script that give the locations
  for the diald control fifo and the diald monitor output fifo.

* Finally got around to documenting the output of the monitor command.

* Added in a "device <devname>" option as an alternative to 
  specifying the device(s) for diald to use at the beginning
  of the command line.
  Diald will still work with the old syntax, but if you want
  to put your device specifications into /etc/diald.conf
  along with everything else, now you can run diald without
  any command line arguments.
  [Note: if you need to pass extra arguments on to pppd
   (e.g. "-- 111.111.111.111:111.111.111.112"), you can
   put these options into your /etc/ppp/options file to
   avoid putting them on the diald command line. This
   means diald can now always be run without any arguments
   that might show someone running ps parts of your system configuration.]
  [Thanks to "Robert Schouwenburg" <Rodos@RodosWorld.hacom.nl>
   for the suggestion.]

* Added in a new timeout "nodev-retry-timeout".
  If diald fails to find a free device, it will wait a short
  period before trying again. This used to be the same as
  the "redial-timeout" parameter. Now you can control
  them independently.

* Added a "reset" command to the list of fifo commands.
  This will cause diald reset its configuration options to the default
  values and then reread its configuration files as well as reprocess
  any command line arguments it might have been given.
  WARNING: if your new configuration has errors the reset command
  may cause diald to terminate with an error condition.
  Ideally this should revert to the previous configuration if there
  is an error in the new one, but that would require a much better
  encapsulation of the configuration information that is currently
  provided by the structure of diald's code.

  NOTE: This hasn't had much testing. I'll be interested to hear how it works.

* Intelegent connect/disconnect scripts that need to know what device they are
  attempting to dial out on can now look at the environment variable
  MODEM, which will contain the name of the device the connect/disconnect
  script is attached to. Those of you who have different types of devices
  that you want to be able to use with the same diald (say an ISDN modem 
  with a propietary command set and a hayes compatiable modem as backup)
  can now do so.

* Added a new rules to the distributed diald.conf file
  that try to deal with the possibility that an attempt to start
  a TCP connection may be fail due to the target site being unreachable.
  The idea is to keep the timeout for the connection from getting
  too long if there is nothing on the other end to respond.
  Look for the rule reading

  accept tcp 15 tcp.syn

  Even if you don't use the distributed diald.conf files I'd be
  interested in hearing if this is a generally useful rule, and
  if the timeout of 15 seconds I choose is perhaps too small for
  general use.

  Thanks to "Bryan A. Pendleton" <bp@bpdomain.access.one.net>
  for asking the questions that lead me to think of this.

* Added a few error messages in to describe what is happening when
  various scripts fail. Hopefully this will help people with initial
  configuration at least a little bit.

* Fixed some bugs that caused diald to die if a monitoring program died
  without shutting down the monitoring feature.
  Part of this seems to be a bug deep down in the stdio functions.
  I haven't tracked it down. I just stopped using stdio and the bug went away.
  The other part was noticing that the other end of the pipe was gone
  (SIGPIPE received) and closing down monitoring output.

* Changed diald to take advantage of bind() calls for SOCK_PACKET
  sockets in newer kernels. This means on recent 1.3.X kernels
  diald won't see every packet that passes through your IP layer.
  If you have a local ethernet then this will substantially reduce
  the load that diald puts on your system.
  If you are using an older kernel, then you won't see any change...

* Complete rewrite of the internal handling of the tcp.live rules.
  This was inspired by a bug fix from Wolfram Grolger.
  After looking at his bug fix for a while I realized that the way
  I was going about handling things just wouldn't stand up to a variety
  of nasty conditions that could happen when packets were being lost
  or TCP stacks on one end or the other of a connection where down.
  Internally diald now watches for FIN packets AND for the
  corresponding ACK packets going in both directions
  before declaring a connection "dead". It is still possible
  that diald can become confused if a link goes down and then
  up again half way through a TCP connection shuting down, but the worst 
  thing that can happen is that the connection is live a bit longer
  than it might otherwise be. In any case, the circumstances
  that could cause this should be extremly rare. Also, the only
  possible fix requires potentially unbounded memory usage by diald.
  I believe the new system is the best possible trade off, and I'll
  continue to believe that until I think of a better one.

* The bug with diald's interaction with kerneld seems to have
  magically gone away. I assume due to changes in the latest versions
  of kerneld. If you are having problems with the interaction between
  kerneld and diald, please update your copy of kerneld.

* Changed UNSAFE_ROUTING so that it can be controlled at run time,
  rather than at compile time. See the new options "reroute" and
  "-reroute" in the manual page. Note that the default setting
  is still controlled from config.h at compile time. It can just
  be adjusted at run time now.

* Made sure that all failed attempts to execute an external program
  are logged by diald. This might ease configuration problems for
  new users.

* Added a proxyarp routing option, mostly taken from pppd. I can't
  test this, so both positive and negative reports about its status
  are welcome.

* Fixed the ip-up and ip-down options so that the scripts get
  the arguments that the manual page says that they do.

* Fixes to the diald-login script in the doc subdirectory.
  Thanks to  Bruce Toback <btoback@netcom.com> for the fixes.

Major changes between version 0.10 and 0.11.
--------------------------------------------

* Changed the way filter rules work to deal better with TCP
  connection shutdowns. There are two main changes.

  First before generating the connection ID diald will swap
  the source and dest addresses if the source is numerically
  larger than the dest. This has the effect of reducing all
  connections to a cannonical ID, regardless of the direction
  the data is really flowing.

  Second, each TCP connection watches for RST and FIN packets
  directly and keeps a variable tcp.live which is 0 only if
  both ends of the connection have been shut down.
  This seems to get around problems where one end shuts down
  before the other, and then has to send some data after
  the FIN packet because some packets got lost.

  If you've been writing your own filter rules, you might
  want to reread the relevant sections of the manual page
  to see how the rules have changed.

* Attemped to fix post connection fowarding to avoid
  seeing ``old'' packets again on the packet filter.
  Of course if replies come back right away, then
  we just see the replies right away, but this
  change just feels "right" to me.

* Added "two-way" option for people who are using diald on
  both ends of a demand dialed link. See the manual page for
  more information.

* Changed diald so that if a script or pppd goes zombie for some
  reason it won't cause diald to die when it fails to reap the child.

* Fixed a bug that caused diald to drop the connection after an
  "up" rule expired, even if the connection was live.

* Added a timeout for the code that waits for information on
  dynamic slip connections.

Major changes between version 0.9 and 0.10.
-------------------------------------------

* Fixed a bug in the buffering code that would cause diald
  to seg fault and disappear in the middle of the night.

* Fixed a bug that allowed diald to get confused about weather
  or not pppd was still running.

* Fixed a bug in the restrict statement interpretation that
  caused diald to parse times with "00" in them as being
  much later than intended.

* Fixed a bug in the restrict timeout code that caused links to
  come up as requested, but never go down.

* Fixed a bug that caused diald to think "chat" failed when it didn't.

* Added fifo options "forced/unforced". Issuing a "force" command
  will bring the link up until an "unforced" command is issued.
  After the unforced command the state of the link will float
  up or down by the normal rules.

* Added a primitive Tk graphical tool for monitoring diald.
  See the file dctrl. You must have tcl/tk installed for to use this.

* Some changes to allow diald to compile with libc-5.x.

Major changes between version 0.8 and 0.9.
------------------------------------------

* Fixed bugs that prevented the FIFO options from working properly.

* Fixed a bug in non-dynamic SLIP mode that made diald attempt to
  get the dynamic address, even though it was not needed.

* Added ip-up and ip-down script options. These serve the same
  purpose as the ip-up and ip-down scritps in pppd, but work
  for both slip and ppp mode. Also, unlike for pppd, these
  scripts are not given hard-coded path names, you specify
  the script name so different copies of diald can run different
  scripts.

* Fixed bug that caused diald to leave a litter of old point to
  point routes around when running in dynamic mode, also fixed
  a bug that causes diald to fail when used in dynamic mode
  with UNSAFE_ROUTING turned off.

* Fixed several bugs in the new zero overhead slip code that
  caused it to fail if UNSAFE_ROUTING was turned off or if
  any compress was used on the link.

* Made a partial fix to failure to count transmitted bytes when
  UNSAFE_ROUTING option is in use. There is no complete fix for both
  SLIP and PPP without changes in the kernel. I could use the pppstats
  structure to fix this for PPP. I have not done so yet.
  In any case, the counts will be correct unless you are forwarding
  packets from another machine across the demand dialed link.

* Added the "rotate-devices" option, originally requested by
  Chuck Mattern <cmattern@mindspring.com>. This causes diald
  to rotate the list of possible devices by one each time it
  attempts a call, thus preventing diald from getting stuck
  if the first device in the list is damaged.

* Added in BOOTP support for dynamic slip mode. See the man page
  under dslip-mode and the config.h file setting for PATH_BOOTPC.

Major changes between version 0.7 and 0.8.
------------------------------------------

* Changed the SLIP code to get rid of the major overhead of moving
  packets from kernel space to user space and back to kernel space.
  The overhead is now the same as for PPP (i.e. only on outgoing packets).
  Also of note, in kernels after 1.3.13, it should be completely
  safe to use the UNSAFE_ROUTING option. With this option
  set there should be no overhead to using diald! (Thanks to Alan Cox
  for getting this change into the kernel!)

* Adding compile time options to make diald work with the PPP 2.2 beta
  releases. Sorry, I can't see a way to make a compiled copy of diald
  work with both ppp-2.1.2 and ppp-2.2, they've gone and changed the
  kernel interface. I'll talk to Al Longyear about it, but I don't
  really expect any miracles.

* Added an "impulse" option to control link up time in larger time
  units than a second. See the manual page.

* Added a way to issue control commands to a running diald via a FIFO.
  I've been meaning to do this for a while, but when 
  Mike Jagdis <jaggy@purplet.demon.co.uk> sent me a patch that was a good
  start on what I wanted. I plugged in bits of his patch and then ran with it.
  See the "fifo" option on the man page for complete details.
  The major bonus here is a way to get a running diald to attach
  to a device that was opened by another program, for example by getty
  in response to an incoming call. You can also block and unblock
  diald's activity and issue all of the commands that can be issued
  to diald with signals. As time goes on I'll probably add more commands
  to this interaction channel.

* Changed the syntax for the "restrict" command.
  The command syntax is now
  restrict <start-time> <end-time> <weekday> <day> <month>
  the <weekday>, <day> and <month> parameters are still in the
  crontab style format, but the <start-time> and <end-time>
  are given in HH:MM:SS format. I think this allows better
  specification of time ranges than the crontab format.
  As a shortcut you can use "*" for either start or end time,
  in which case they default to 00:00:00 and 23:59:59 respectively.

* Changed the semantics of "accept" filters with timeout 0.
  Timeout 0 used to mean that the accept rule behaved exactly
  like and ignore rule. Timeout 0 now means to kill the matched
  connection immediately.
  ******* WARNING ********
  This is an incompatible change! You must change all rules in your
  /etc/diald.conf that have timeout 0 to ignore rule! For example,
  the rule "accept tcp 0 tcp.fin" should become "ignore tcp tcp.fin".

* Changed the timer code so that it should be immue to changes
  in the wall clock. This should allow diald to be run along with
  xntpd or other time adjusting protocols.

* Added the BUFFER_PACKETS configuration option. If you define
  this option diald will store packets that get sent when the link
  is down and forward them once it manages to establish the link.
  This should fix the response delay people see on the first
  attempt at a telnet or rlogin when the link is down.
  Note that if your connect takes a long time to start up you
  might still want to muck with the kernel setting of TCP_SYN_RETRIES.

* Added in pidfile option. Made diald write out it's pid to /var/run/diald.pid
  by default. Be careful to use the pidfile option if you want
  to run multiple copies of diald, or they will all write to /var/run/daild.pid.

* Made diald re-open the modem line just before running the disconnect
  script. This means those users who want to can use the disconnect
  script to query the modem for state flags, e.g. to determine why
  the connection was terminated.

Major changes between version 0.6 and 0.7.
------------------------------------------

* Fixed routing so that when the connection goes down the
  point to point route to the proxy device is restored.

* Fixed minor bug in code to read dynamic IP address off the
  banner send by dynamic SLIP. If the buffer has a non IP
  address number in it, it used to be interpreted as an IP number.
  Now it just gets skipped over.

* Configuration parsing imposed an artificial limit on the size
  of timeouts. The restriction has been removed. If you want
  a 2^31-1 second timeout, now you can have it.

* Added in UNSAFE_ROUTING configuration option. Using this
  option eliminates the overhead of reading packets off the
  proxy and forwarding them to the physical link by changing
  all routes to point to the physical link while it is up.
  Note without this option diald does not introduce an overhead on
  incoming packets, only on going packets.

  Be warned that I am not at all sure this option works safely.
  I'd be interested to hear how it works for people, but don't
  use it unless you are willing to chance TCP lockups.

* Added time restrictions to filter rules. See the "restrict"
  option in the man page.

* Added four new classes of filter rules, and got rid of reject rules.
  Accept rules are the same as before. I've added in "bringup",
  "keepup" and "ignore" rules. I have also added the rules "up" and "down",
  which force the link up or down during the currently applicable time
  restriction. See the manual page for more information.

* I have exchanged the meaning of SIGTERM and SIGINT as signals to diald.
  SIGTERM now terminates diald and SIGINT now shuts down the link if
  it is up. This is so diald will terminate cleanly on shutdown.

* Changed accounting log code to open the file before each update,
  and then close it again after the update. This allows atomic
  rotation of the accounting logs without shutting down diald.
  Look in the contrib directory for some interesting scripts that
  process the accouting logs.

Major changes between version 0.5 and 0.6.
------------------------------------------

* None

Major changes between version 0.4 and 0.5.
------------------------------------------

* Fixed bugs in the options file parser that caused core dumps
  when compiled as a QMAGIC executable.

* Fixed various bugs in the timer code that caused early timeouts.

* Fixed bugs in the filter code that caused IP packets to get ignored
  when determining the idle timeout.

Major changes between version 0.3 and 0.4.
------------------------------------------

* ANSIized the code. This caught a bunch of coding inconsistencies,
  but did not result in any major changes. Things compile clean
  with -Wall now.

* Added in addroute and delroute script options to allow users to do local
  routing work when diald starts and ends.

* Added in primitive ability to use more than one device. diald searches
  for an unlocked device on a list and uses that one. Note that it
  will try to run the same connect script regardless of the device
  it gets. This isn't really ideal. Eventually I'll have to rewrite
  the option syntax to accommodate a proper modem server format.

* Fixed modem locking bugs. You can all stop sending me messages
  about this now.

* Added in an option to allow diald to work with dynamic slip and ppp
  addresses.

* Added in an accounting log file. This is intended to record information
  salient to getting charges reimbursed by an accounting department.
  Check out the option "-accounting-log" in the man page.

* Added a "netmask" option to diald, acts like "netmask" in pppd.

* Changed name of "default" option to "defaultroute" to match pppd.

* Fixed some more problems with the modem hanging for 30 seconds when
  dialing went wrong, or some other process mucked up the modem device.

* Rewrote the packet filtering code. The goal of the rewrite was a redesign
  to accommodate a possible future move of the packet filtering code into
  the kernel. This would allow diald to act as a firewall as well as a
  dialer daemon. There are some minor user visible differences as a result.
  The most notable is that the "filter" command has been replaced
  with the commands "accept" and "reject". Note that the "reject" command
  does not actually do anything yet, for now it is equivalent to an
  accept command with timeout 0.  The other visible change is the
  ability to define variable names and protocol rule names in the
  configuration files. Note that diald does NOT yet actually act as 
  a firewall, and will never do so without kernel modifications.

* Added options to allow run time definition of variable names for
  filter rules, as well as named protocol rules. As a result I have
  moved the default definitions out of the code and into the file
  /etc/diald.defs. This file is the first file read when diald starts.

Major changes between version 0.2 and 0.3.
------------------------------------------
This is a bug fix release.

* I think I finally tracked down the cause of those intermittent
  modem "hangs" were the OS waited 30 seconds for some buffers to drain
  before finishing a close. This problem should be gone.

* Spelling fixes thanks to Hugues Lafarge <hugues@afp.com>.

* Stupid bug that causes SLIP mode to hang up immediately fixed.
  SLIP mode should actually work now.

* Diald wasn't seeing SIGHUP's in SLIP mode. I forgot to set the
  session group and controlling tty. Fixing this caused, pppd SIGHUP's
  to break. The solution is to give pppd the controlling tty in fork
  just before exec.

* Added a "disconnect" script ala pppd. I don't need this myself,
  but maybe someone out there will.

Major changes between version 0.1 and 0.2.
------------------------------------------
diald has been almost completely rewritten (twice!) since the
first release. There are many changes. Here are the high points:

* The ppp-on script is no longer used. Diald will run a connect
  script (chat works nicely) by itself, and then run pppd if needed.
  This is so diald can know the pid of the pppd process, which allows
  diald to know what ppp interface (ppp0, ppp1, etc.) the pppd is
  running on, and allows diald to know what process to kill to take
  down the link. The old diald just issued a killall -INT pppd,
  which prohibited more than one diald running, or a diald controlled
  pppd running together with a non-diald controlled pppd.

* There are LOTS of configurable options now. Look at the usage
  line (just run diald without any options) or read the man page.
  The man page still needs some work, but I hope it will be enough
  to get experienced users up and running. (Hey, this is still ALPHA
  software, I only have so much spare time).

* The entire mechanism for controlling the state of the link has been
  replaced by a formal state machine. I think this machine guarantees
  that no more than one child process can be active at a time, and
  will even kill off child processes that are taking to long to do
  their tasks. Let me know if you have problems with this. The old diald
  could be forced to spawn hundreds of chat scripts or pppd daemons.

* Diald no longer uses slattach to set up the slip link. It just does it
  by itself. This allows it to know which slip device it is using,
  which should allow multiple diald's to run at the same time.

* The policy for bringing up and shutting down the link is now very
  configurable, down to the level of choosing what packets
  should bring the link up and keep it alive, together with
  multiple timeouts on connections over the link.
  Look at the manual page and the sample diald.conf files in the
  doc subdirectory. Ask me if you are having problems configuring
  diald to do something you want. It will help me to write a better
  manual page, and will point deficiencies in the current design.

* UUCP style locks are now placed on the call-out device.
