eglamkowski's Journal: pk

And another problem I'm having:

I am try to unzip this file on a linux box and am getting:
unsupported compression method 99

As per here: http://members.tripod.com/~petlibrary/ZIP.HTM

I have this one file where byte 8 is "63" but compression methods are values supposed to range from 0 to 8? It isn't clear if each nibble can have a separate value of 0 to 8 and thus there can be four compression flags (one for each nibble in bytes 8 and 9), or if 63 is just not a valid value here.

Otherwise bit 1 of byte 6 is set, which, if we assume the compression value of 6 is indeed what is meant by the first nibble of byte 8, then that would mean:
if compression method 6 used (imploding), 8K sliding dictionary.

UPDATE:
fsck me, I'm running into the little endian vs. big endian thing. Gotta do some byte swapping to match up to the documentation... Grrrr....
http://www.pkware.com/documents/casestudies/APPNOTE.TXT

UPDATE:
And that's it:
AE-2 with 256-bit encryption key using the deflated compression method.

Bleh.

UPDATE:

7za can decompress/decrypt the AE-2 format.

Just in case you're wondering.