Reverse engineering CRC?

[Gregory Ewing]

Lawrence D'Oliveiro wrote:

> They could be using a strong cryptographic hash and truncating it to 16 bits 
> or something.
> 
> In which case you’ve got your work cut out for you...

Nope, I've determined that it's actually a pretty standard
CRC, and it's even using one of the standard polynomials,
0x8005. I'll explain the details of how I figured that
out in my essay.

What confused me initially is that it seems to be adding
a few extra bytes to the checked data that aren't present
in the file. Figuring out what they're supposed to contain
is proving to be quite a headache...

-- 
Greg