RadiusClient fail with password with more than 16characters

[GoogleCodeExporter]

RFC 2865 says:

      Call the shared secret S and the pseudo-random 128-bit Request
      Authenticator RA.  Break the password into 16-octet chunks p1, p2,
      etc.  with the last one padded at the end with nulls to a 16-octet
      boundary.  Call the ciphertext blocks c(1), c(2), etc.  We'll need
      intermediate values b1, b2, etc.

         b1 = MD5(S + RA)       c(1) = p1 xor b1
         b2 = MD5(S + c(1))     c(2) = p2 xor b2
                .                       .
                .                       .
                .                       .
         bi = MD5(S + c(i-1))   c(i) = pi xor bi

      The String will contain c(1)+c(2)+...+c(i) where + denotes
      concatenation.

However when calculating b2, b3, b4, etc. Secret+P1, Secret+P2, Secret+P3, etc 
is used, when it should have been c(1), c(2), c(3), etc.

This means that passwords longer than 16bytes will be calculated wrong and will 
not work.

Attached is patch that fixes the problem..

Hope this help you (or someone else)

Cheers

Esben

Original issue reported on code.google.com by [email protected] on 16 May 2013 at 9:10

Attachments:

• AccessRequest.patch