john-users - an issue with dynamic_6 hashes with hex salts

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Date: Mon, 06 Aug 2012 01:58:48 +0200
From: arcctgx <arcctgx@...zta.onet.pl>
To: john-users@...ts.openwall.com
Subject: an issue with dynamic_6 hashes with hex salts

I'm using john 1.7.9-jumbo-6_omp [linux-x86-64]. I have two files: 
example.hash and example.pot:

 > wc -l example.*
   442 example.hash
   319 example.pot

example.hash contains dynamic_6 hashes with 3-byte salts in hex format. 
example.pot is the corresponding .pot file created some time ago with 
jumbo-5. All the recovered hashes in example.pot have salts in hex format.

It seems that jumbo-6 has trouble reading the .pot file created by jumbo-5:

 > john -show -pot=example.pot example.hash
0 password hashes cracked, 442 left

I re-cracked the example with jumbo-6 using the known passwords from 
example.pot:

 > cut -d: -f2- example.pot | john -stdin -pot=exa2.pot example.hash
(...)
guesses: 319

So far, so good. But then:

 > john -show -pot=exa2.pot example.hash
(...)
305 password hashes cracked, 137 left

14 hashes seem to be missing, but they have actually been cracked and 
have been written to the .pot file. The missing 14 hashes have salts in 
hex format - I presume it's because the salts contain $ or :. The 305 
recognized hashes have their salts written as a "normal" string in exa2.pot.

Why doesn't jumbo-6 recognize the hashes with hex salts as already 
cracked? It used to work in jumbo-5. What am I missing? Do I need to 
specify some extra option for the hex salts to work?

I tried using non-OMP build of jumbo-6 compiled with linux-x86-mmx make 
target on a different machine (32-bit Athlon CPU), but the results were 
the same.

In case anyone wants to experiment/confirm, the files are here:
example.hash: http://pastebin.com/vZd34eLH
example.pot: http://pastebin.com/Hcnipjd3
exa2.pot: http://pastebin.com/dNnHLD5Y

Best regards,
arcctgx

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