Re: [Full-Disclosure] Sending remote procedure calls through e-mail (RPC-Mail)

From: Barrie Dempster (barrie_at_reboot-robot.net)
Date: 10/20/04

  • Next message: Pablo: "Re: [Full-Disclosure] Web browsers - a mini-farce"
    To: full-disclosure@lists.netsys.com
    Date: Wed, 20 Oct 2004 12:28:50 +0100
    
    
    

    Few points to note on this idea,
    Encryption? you didn't mention it I hope you considered it though. This
    detracts from the simplicity as the user will have to setup this
    alongside their mail client.

    Speed, email is much slower and less reliable than port-knocking. (You
    have to rely on more than just the box your accessing being up, all the
    intermittent email servers must be playing the game too)

    IMO if the port knocking is to, say for example, open up a remote shell.
    We could alias the command ssh on the users machine to a script which
    runs the port-knocking command before executing ssh making the process
    completely transparent to the end user.

    It's as you point out a matter of convenience however I'm sure running
    one command is more convenient than.....
    1. Fire up the email client
    2. Type the email address and message, ensuring to type the passphrase
    and encrypt the mail.
    3. send the mail
    4. Wait a comparatively long time for a confirmation reply.

    With the portknocking method if the server is down you will be notified,
    how will your email server tell you this? as in your example the command
    is only acted upon when the receiving server checks for incoming mail.
    Or are you going to add notification of unread mail to the email server,
    adding more complexity and another failure point to the mechanism.

    It is a fairly good idea and I've seen it implemented before, I also did
    a similar thing over IRC as an experiment which worked pretty well.

    However I don't think it beats port-knocking on reliability, speed or
    security, Which I consider important aspects of this kind of technology.

    Kindest Regards

    -- 
    Barrie Dempster (zeedo) - Fortiter et Strenue
      http://www.bsrf.org.uk
    [ gpg --recv-keys --keyserver www.keyserver.net 0x96025FD0 ]
    
    

    _______________________________________________
    Full-Disclosure - We believe in it.
    Charter: http://lists.netsys.com/full-disclosure-charter.html



  • Next message: Pablo: "Re: [Full-Disclosure] Web browsers - a mini-farce"

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