How is .net generating extra bits in MD5?

From: Pete (jpeteb_at_hotmail.com)
Date: 01/21/05

  • Next message: Valery Pryamikov: "Re: How is .net generating extra bits in MD5?" 
    Date: 21 Jan 2005 11:53:48 -0800

    Hi,

    I have a piece of .net code I am trying to understand. It creates a MD5
    hash then requests 256 bits from the hash, where MD5 only generates 128
    bits. I've looked at the hash with another non-.net piece of code and
    the first 128 bits match up correctly. How is Microsoft creating the
    second 128 bits? I cannot seem to figure that out. Here is a code
    fragment in C#:

    string passPhrase; // password string
    string saltValue; // salt string
    string hashAlgorithm; // set to "MD5"
    int passwordIterations; // set to 2
    int keySize; // set to 256

    byte[] initVectorBytes = Encoding.ASCII.GetBytes(initVector);
    byte[] saltValueBytes = Encoding.ASCII.GetBytes(saltValue);

    PasswordDeriveBytes password = new PasswordDeriveBytes(
    passPhrase,
    saltValueBytes,
    hashAlgorithm,
    passwordIterations);
    byte[] keyBytes = password.GetBytes(keySize / 8);

    TIA for any help.

  • Next message: Valery Pryamikov: "Re: How is .net generating extra bits in MD5?"

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