Howard,
I think you are reading the code wrong. In #processFinalBuffer:bitLength: a final buffer of soze 64 BYTES is being created and populated. That is 512 bits. Both SecureHashAlgorithm, from the base image, and SHA1, from the Cryptography Team Package are doing this.
Rob
----- Original Message ----- From: "Howard Stearns" howard.stearns@qwaq.com To: "The general-purpose Squeak developers list" squeak-dev@lists.squeakfoundation.org Sent: Monday, October 29, 2007 2:05 PM Subject: does SecureHashAlgorithm pad correctly?
The class comment for SecureHashAlgorithm says it implements the SHA standard, but I'm not sure it's padding correctly.
My reading of the standard is that all messages -- including zero length messages -- should be padded to 512 bit size in a certain way.
See section "4. Message Padding" of http://www.itl.nist.gov/fipspubs/fip180-1.htm
My reading of the code is that it explicitly fails with an error for zero length messages, and pads to 64 bit sizes.
Am I nuts?
-- Howard Stearns AIM: qwaqHoward Qwaq: +1-650-331-1437 office: +1-608-850-4482 mobile: +1-608-658-2419