Re: Passwords on Linux systems(for all flavors)

From: Glynn Clements (glynn_at_gclements.plus.com)
Date: 07/10/05

  • Next message: Kurt Seifried: "Re: Passwords on Linux systems(for all flavors)"
    Date: Sun, 10 Jul 2005 22:02:43 +0100
    To: shyaam@gmail.com
    
    

    shyaam@gmail.com wrote:

    > I would like to know the place where I can find the linux password
    > constraints for the various linux flavors. What I mean is the details
    > like number of key spaces or the key length, the types of charactors
    > that can be used, the restrictions and the number of times the
    > password can be tried if not infinite, etc. I am in need of these
    > details very urgently, so please do help me on this topic.

    On any system which uses PAM (which is almost every modern Linux
    system), most of these are configuration options, controlled through
    the files in /etc/pam.d and /etc/security.

    For the underlying libc crypt() function, assuming MD5 passwords, the
    password can be any NUL-terminated string. There is no minimum or
    maximum length, nor any restriction on which characters (bytes) the
    password can contain.

    However, if a password contains any control characters or non-ASCII
    (8-bit) characters, there may be problems entering it in certain
    contexts. Also, individual programs may read the password into a
    fixed-size buffer, which will impose an upper limit on the length of a
    password.

    -- 
    Glynn Clements <glynn@gclements.plus.com>
    

  • Next message: Kurt Seifried: "Re: Passwords on Linux systems(for all flavors)"

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    • Re: Passwords on Linux systems(for all flavors)
      ... >>constraints for the various linux flavors. ... >>like number of key spaces or the key length, ... nor any restriction on which characters the ... if a password contains any control characters or non-ASCII ...
      (Focus-Linux)
    • RE: Passwords on Linux systems(for all flavors)
      ... Passwords on Linux systems ... > constraints for the various linux flavors. ... > like number of key spaces or the key length, ...
      (Focus-Linux)