[cryptography] Peer review request - Loplop

CodesInChaos codesinchaos at gmail.com
Mon Nov 19 05:53:22 EST 2012

I didn't look at your code, but from what I remember oplop is a silly scheme:

1. Doesn't strengthen the password (Uses MD5 instead of PBKDF2, scrypt,...)
2. No clean domain separation between username and password
3. The algorithm that ensures that the password contains numbers is really weird
   and leads to biased outputs. Should use a rejection based approach instead.
4. It uses MD5 instead of a newer hash-functions. While collisions
don't affect the scheme,
   it's still preferable to use a strong hash-function.

The first issue reduces security significantly, the rest are mainly
ugly but not too dangerous.

We had a discussion of oplop on crypto.SE a few months ago:

More information about the cryptography mailing list