rohe/pyjwkest — pull request #2 by hdknr (2013-03-27 04:18:23+00:00)
Title: block counter start 2.

Because I'm not an export about GCM, I could be missing something important.

Bock counter ( last 4 bytes of 16 bytes "icb" ) is initialized as "1".
And it was incremented(inc32 called) before a block would be encrypted( EBC).
It means that the block counter actually starts with 2.