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    antihack
    current version:     1.8.0
    by:                  Rikard Johansson

    This application is a simple server written in c. Whenever an incoming
    connection is established, corresponding functions is executed in the lua
    script file making it easy to respond to unwanted connections.

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 version 1.0.0, 2010-03-25
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    * TCP support
    * Arguments
        -p PORT     specify listen port (default 22)
        -d          daemonize
    * script.lua
        + void incoming_connection(timestamp, ip, port)
        + bool send_reply()
        + string reply_message()
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 version 1.1.0, 2010-03-25
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    * Ability to fork and lock incoming connection
    * script.lua
        + bool close_connection()
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 version 1.1.1, 2010-03-25
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    * Bugfix: forked process didn't exit when client closed connection
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 version 1.2.0, 2010-03-25
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    * Updated commandline argument handling
    * script.lua
        * string reply_message(timestamp, ip)
        + void data_received(timestamp, ip, data)
    * Cleaned up code
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 version 1.3.0, 2010-03-25
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    * Removed long commandline arguments
    * script.lua
        * void connection_established(timestamp, ip)
        + void connection_closed(timestamp, ip)
    * Bugfix: not daemonize before socket is created successfully
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 version 1.4.0, 2010-03-26
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    * script.lua
        Added timestamp, ip and port as parameters to all functions
        * void connection_closed(timestamp, ip, port, duration)
    * Bugfix: buffer reset with zeros before each receive
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 version 1.5.0, 2010-03-26
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    * script.lua
        * string data_received(timestamp, ip, port, data)
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 version 1.6.0, 2010-03-26
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    * Improved socket closing
    * Arguments
        -s SCRIPT   specify script to use
    * script.lua
        - bool send_reply(timestamp, ip, port)
        + bool wait_for_more_data(timestamp, ip, port, last_incoming_data)
        * bool reject_connection(timestamp, ip, port)
    * Script for static simulation of webserver
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 version 1.7.0, 2010-03-29
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    * script.lua
        * string welcome_message(timestamp, ip, port)
    * Bugfix: added interrupt handler for SIGCHLD to avoid zombie processes
    * Bugfix: kill program if daemonize fails
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 version 1.8.0, 2010-04-01
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    * Added interrupt handling for SIGUSR1 which reloads the lua script file
    * Bugfix: reassign socket fd when forking to close correct on interrupt
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