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Underhanded C Contest announces winners

Posted by CmdrTaco on from the games-people-play dept.

Matthew Skala writes "The 2005 Underhanded C Contest has announced its winners: the team entry from M Joonas Pihlaja and Paul V-Khuong, and the solo entry from Natori Shin. The contest (which appeared on Slashdot in June) tests programmers' ability to hide malicious behaviour in innocent-seeming code, making it a kind of evil shadow twin to the International Obfuscated C Contest."

6 of 150 comments (clear)

  1. Re:I'm still fond of this one by Anonymous Coward · · Score: 5, Informative

    This one almost made it into the Linux kernel.

    It *did* make it into the kernel for anyone using the BK-to-CVS gateway.

  2. Runtime code generation by pkhuong · · Score: 4, Informative

    The CLR does JIT (or, at least, runtime) compilation. A common way to do so is to output the machine code on the stack. W^X usually breaks programs that do runtime code generation. Now, this is a WAG, but that's where my money's at.

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  3. Re:I'm still fond of this one by jnf · · Score: 5, Informative

    to anyone who makes a routine of putting their constants on the left hand side of the expression, that becomes not very hard to notice .. although intermixed with several megabytes of source it becomes less obvious. What I mean is: if (( (__WCLONE|__WALL) == options && 0 = current->uid)) will throw an error, whereas 0 == current->uid will not.

  4. Re:Will Code For Beer by anagama · · Score: 3, Informative

    Actually, what you describe is "positive punishment" (apply negative stimulus in the presence of a certain bahavior -- like a spanking for swearing). "Positive" is not used in the "good/bad" sense, put in the "plus/minus" sense.

    Negative reinforcement is a reward that occurs by subtracting an adverse stimulus from the environment. For example, Fridays are a form of negative reinforcement -- the withdrawal of a negative stimulus (work) is rewarding, makes people feel good/relieved, and thus, people come to really like Friday afternoons. http://en.wikipedia.org/wiki/Reinforcement#Positiv e_vs._negative

    --
    What changed under Obama? Nothing Good
  5. Re:I'm still fond of this one by Tim+C · · Score: 3, Informative

    It's not that assignments aren't allowed in if statements, but that Java has boolean types. So while a statement like i = 0 does return 0 (as in C), unlike C 0 is not false, it's an int, and so if (0) is a compile time error.

    You can still do things like if ((line = in.readLine()) == null) of course

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    It's official. Most of you are morons.
  6. Ken Thompson... by Sam+Nitzberg · · Score: 4, Informative

    It's not exactly the same thing, but the most powerful and clever C code example with an 'underhanded' purpose must be Ken Thompson's classic...

    Reflections on Trusting Trust
    http://www.acm.org/classics/sep95/

    Other interesting papers that come to mind include Tom Duff's on Unix viruses, as well as McIlroy.

    Sam

    sam @ iamsam.com
    http: /www . iamsam . com