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Allowable characters for PSK?

Discussion in 'Tomato Firmware' started by Vezado, Jun 23, 2009.

  1. Vezado

    Vezado Addicted to LI Member

    Does anyone know where I can a list of all allowed characters for PSK passwords? I've discovered that some characters are accepted by the Tomato GUI but are not actually usable and them i must connect via ethernet to fix the issue. I'd like to add some upper ANSI characters to increase pw complexity but doing it trial and error is less that desirable. If i can get a list of characters, i can specify it in my pw manager (KeePass) and it will create a complex pw using only those characters. Thanks!
     
  2. bogderpirat

    bogderpirat Network Guru Member

    i'd say anything ASCII (8bit) is allowed
     
  3. ringer004

    ringer004 LI Guru Member

    You are solving a non-problem.

    Using the upper ASCII char set will cause you nothing but trouble, possible compatibility issues with your router, and very likely issues with how ever many unique wireless clients you have, with absolutely no benefit whatsoever.

    All you need to use is upper case letters, lower case letters, and digits. Make sure your PSK is *completely random*. No address where you live , no birthdays, no pets names, etc.

    A PSK that is completely random that is of sufficient length is unbreakable, unless there is a fundamental flaw in the WPA[2] algorithms, in which case it won't matter how long your password is, or what character set you're using.

    Assume your password is 12 random characters of upper case, lower case, and digits. This has 62 (26 + 26 + 10) possible characters.

    62 ^ 12 = 3226266762397899821056 total possibilities

    Now assume someone really wants to crack your network, and throws enough hardware resources at the problem to attempt *one million* passwords per second.

    this results in 3226266762397899.821056 seconds,

    or 37341050490.716... days

    or 102234224.478... years

    If you are not comfortable with 100+ million years, then make your password even longer... (but only use the char set from above and avoid all compatibility issues).
     
  4. ringer004

    ringer004 LI Guru Member

    More data points - may be useful

    Assume only use upper case, lower case, and digits.
    Assume attacker can process 1,000,000 possibilities per second.

    Password length #Years to crack

    6 0.0018
    7 0.1116
    8 6.9188
    9 428.964
    10 26595.792
    11 1648939.104
    12 102234224.478

    So, a password length of 9 random characters is likely all anyone will ever need.
     
  5. Vezado

    Vezado Addicted to LI Member

    OK, fair enough. I figured since the goal of the password was complexity I'd take it as far as possible.

    For the record, bogderpirat seems to be correct in that characters 1-255 are allowed with a few characters in the middle that are not usable. Anything over 255 causes it to fail.
     

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