Short:        Mail bomb protection for BBSes (Arexx)
Author:       mat@darkside.demon.co.uk (Mat Bettinson)
Uploader:     mat darkside demon co uk (Mat Bettinson)
Type:         comm/bbs
Architecture: m68k-amigaos

             _____        __                       ____   ___  
            |  __ \      / _|                     |___ \ / _ \ 
            | |  | | ___| |_ _   _ ___  ___ _ __    __) | | | |
            | |  | |/ _ \  _| | | / __|/ _ \ '__|  |__ <| | | |
            | |__| |  __/ | | |_| \__ \  __/ |     ___) | |_| |
            |_____/ \___|_|  \__,_|___/\___|_|    |____(_)___/ 
                                                   
     Mail Bomb and Resume Damage protection and repair by Mat Bettinson
                      of the London Xenolink Alliance.

New for 3.0:

3.0 operates basically the same way but has PROPER LHA RESUME damage
checking that WORKS. Really! You can also turn it off. have a peek at the
start of the script as you may have to change some bits.

I killed the VERBOSE feature below leaving a standard medium level of
logging throughout. The rest of the arguments will be parsed to LHA instead. 

IE Rx Defuser %s -b100 

Will parse -b100 to LHA etc... 

LHA checking is relatively time consuming and may take as long as the
unpacking! Well not THAT bad but it isn't nippy. It'll have to stay that way
until coded in something quicker OR just turn it off by removing the TP =
'YES' line in the header of the script. 

<-----------------------------------CUT----------------------------------->

** New additions to 2.5 indicated by **

Bugger it. I can't find the original docs (did I do some?) so I've knocked
up a quick doc and instead of encoding it I'll post as a message.

<-----------------------------------CUT----------------------------------->

Excuse the quick docs. I'm sure you'll appreciate the urgency. 

Defuser 2.0 is basically the same as the earlier version but since it's been
pulling in my mail for the BBS for weeks it seems to be stable and it
catches Mail-Bombs and Trapdoor Abortions when I throw them at it. 

How to use: (it's easy)

Copy Defuser.rexx to rexx: on your system.

Couple of software examples:

Spot: Sytem menu. C:LHA x will be there. Actually this simple command will
      be in most software. Simple replace with 'rx Defuser'

Most BBS software is the same. Noteable exception is Xenolink:

LZH:.LZH ?? ?? 2D 6C 68
   EXTRACT = rx defuser %s
   ARCHIVE = C:LHA -0 -m -N -q a

LHA:.LHA ?? ?? 2D 6C 68
   EXTRACT = rx defuser %s
   ARCHIVE = C:LHA -2 -m -N -q a

In Xconfig:Archivers.config

Likewise in any other software just replaces the LHA x with 'rx Defuser'

There's also a bit that you can edit in the Arexx program itself:

*/
EXEdir = 'C:'
MaxSize = 75000
MaxArc = 3000000
Logfile = 'MAIL:Defuser.log'
BadPKT = 'XIN:BAD/'
LHAOpt = 'x -q'
BBSTemp = ''
CheckResume = 'YES'

/*

** New for 2.5: There is now a BBStemp line here. If your BBS software uses
** temp files you can place the name there. If nulled (as default) ALL files
** assumed to be mail packets. This will cause no harm but will fill your
** inbound with crap files where defuser guessed wrong.

## New for 3.0 the CheckResume line. Enables or disables this function.
## With it OFF you'll not notice Defuser at all and be given mail bomb
## protection. With it ON the time can be noticable on large packets but
## you WILL NOT lose mail from Resume-Append damaged packets.

EXEdir is the place where your LHA, Copy, Delete etc live. 
MaxSize is the maximum size of the INDIVIDUAL packets in your mail packet.
        this may need to be raised to a very high value if your Boss sends
        packets over 64K. 
MaxArc is the largest size of the extracted mail archive. Just make a large 
       value but well under the space free on your inbound.
Logfile is the full path and filename of the Defuser log where it will 
        report all actions to since a console is hardly ever available.
BadPKT is the dir to sling suspect packets that file for closer inspection
       and/or deletion by yourself. Needs ':' or '/' at the end.
LHAOpt is the LHA options you would normally use to extract. The q switch
       in this case makes it quiet and the x switch is your extract command.

Right... The actual TRAP PRONG section of the code doesn't need any
configuring... Defuser will log it's actions to the log file and it will
strip the appended file/files off and save as the same packet name only with
a bumped extention IE TH0 becomes TH1 etc... It WILL check to see if it
exists before doing so in which case it will pick a higher extention and so
on. :-) No pissy coding here! :-) 

OK so it will extract the FIRST file obviously but it WILL NOT extract the
remaining files. This is so it's logged in your BBS software and lazyness
(!) and security and it works! :-) You just have to perform another import
to catch the file again. If it STILL isn't a single file Defuser will again
strip the remainer off save it out and extract the first bit and so on... 

All actions will be logged in the log file as usual.

OK that's it. 

Fiver in the post for saving your mail eh? :-) 

BTW I've tried to E-Mail those Bugger Trapdoor Authors but their host has
mysteriously vanished according to Demon. :-/ I'll send a Net-Mail and if
anyone wants to post Defuser in a News group etc then go right ahead. I'm
not going to as those Internet types hardly ever bother with Fido. :-|

Stay safe and may the mail flow.

Mat Bettinson:  Fidonet 2:254/205  Amiganet 39:139/5 
                E-Mail mat@darkside.demon.co.uk
     _ ___
/\/\(-) |  Sysop of Creations, plot hatcher and general Aussie Nuisance.  

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