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Covert Channel: ASCII Art Over ICMP

Posted by michael on from the help-i'm-trapped-inside-a-chinese-fortune-cookie-factory dept.

An anonymous reader writes "Have you ever had a particularly lossy Cisco ping, which you were sure was trying to tell you something? I mean, really *tell* you something. Echoart allows you to return a simple ascii art image in response to a Cisco-style ping."

8 of 147 comments (clear)

  1. Re:Nothing new ... by jonman_d · · Score: 1, Informative

    Who the hell modded this insightful?

    Banner(6) is a *nix program which outputs ASCII art of a string, on the standard output.

    This program sends packets in a designated pattern, and it can be used to send ASCII art of any kind, over ICMP.

    These two programs have almost nothing in common, except that you could probably use banner to create the art for this program.

    --

    --
    http://nemilar.net - Not your grandmother's soup kitchen
  2. mirror by whizkid042 · · Score: 4, Informative
    this server seems to be quite slow ... here is a mirror

    http://www.unixauthority.com/~fiskeja/mirror/mirro r1.internap.com/echoart/

  3. Re:Ascii art programs out there? by Anonymous Coward · · Score: 2, Informative

    google query

    Have a look.

  4. Building the art by Derek+Mason · · Score: 2, Informative

    This looks neat - but it would help if there was a way to build the ASCII art from text within the program. In the meantime Email Effects will do the trick very nicely.

  5. Re:Ascii art programs out there? by Anonymous Coward · · Score: 1, Informative

    There is a web based app up at:

    http://www.jdneff.com/

  6. Re:Cisco-style ping? by Eshelbyk · · Score: 2, Informative

    It's not so much the ping itself, rather how the results are displayed on a Cisco IOS device when you issue a ping command. Bangs and dots.

  7. Re:Oh, great by nervous_twitch · · Score: 2, Informative
    Tell me, if my computer silently drops all unsolicited incoming data, how do you tell it's there?

    If a host is not found on the network, the nearest router is expected to send an ICMP "Host Unreachable" message to the sender.

    --
    Trees everywhere, and not a forest in sight.
  8. Re:Oh, great by Anonymous Coward · · Score: 1, Informative

    wow, another windows weenie.

    BECAUSE, GENIUS, SILENTLY DROPPING PACKETS IS CONTRARY TO THE RFC's. If a router is agreeing to pass the packets to the target address, and no reply or rejection or acknowledgement is being returned, then we know that the router believes there is a machine ready to receive the packets. Fyodor has honed nmap's ability to tell whether there is legitimate packet loss, network issues or whatever, of if the machine is using a packet filter. you have been brainwashed by that steve gibson freak, or some other software firewall developer into handing out cash for a security blanket. good work.