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Date: Fri, 15 Jun 2012 18:58:15 +0200
From: Frank Dittrich <frank_dittrich@...mail.com>
To: john-dev@...ts.openwall.com
Subject: More Markov mode patches (but still no --markov=section...)

Hi,

some more changes for Markov mode.
IMO useful enhancements, but still no --markov=SECTION support

The 3rd patch touches config.c and config.h, but the change is trivial.
Otherwise, only Markov mode specific files are changed.


[PATCH 1/4] Markov mode: move parameter validation into new function
 get_markov_options Additionaly, the logic has been
 changed so that the max. values for level and length
 are adjusted prior to checking min. values, to avoid
 adjusting min. value to a max. value which is changed
 afterwards:

Instead of
$ ./john --markov=501-500:0:0:35-31 --stdout
Warning: max level(500) < min level(501), min level set to 500
Warning: minimum length(35) < maximum length(31), minimum length set to 31
Warning: Maxlen = 31 is too large (max = 30)
Warning: Level = 500 is too large (max = 400)
MKV start (lvl=500-400 len=31-30 pwd=182847102117099741)
the new logic will be
$ ./john --markov=501-500:0:0:35-31 --stdout
Warning: Level = 500 is too large (max = 400)
Warning: Maxlen = 31 is too large (max = 30)
Warning: max level(400) < min level(501), min level set to 400
Warning: minimum length(35) < maximum length(30), minimum length set to 30
MKV start (lvl=400-400 len=30-30 pwd=182847102117099741)

Furthermore, maxlen > MAX_MKV_LEN will only be checked if
db->format->params.plaintext_length > MAX_MKV_LEN.
(Otherwise, the format specific max. length is the limit.)


[PATCH 2/4] genmkvpwd should use MAX_MKV_LVL

Furthermore, for level 0, calculate statistics up to level MAX_MKV_LVL


[PATCH 3/4] Markov: different error messages for missing
 [Markov:Default] section and for missing Statsfile
 definition in an existing [Markov:Default] section


[PATCH 4/4] Markov: improved logging

$ ./john pw --markov
Loaded 1 password hash (dummy [N/A])
MKV start (stats=$JOHN/stats, lvl=200 len=12 pwd=259356431)

0:00:00:00 Proceeding with Markov mode
0:00:00:00 - Statsfile: $JOHN/stats
0:00:00:00 - Markov level: 0 - 200
0:00:00:00 - Length: 0 - 12
0:00:00:00 - Start-End: 0 - 259356431

$ ./john pw --markov=100-200:0:25935643:6-10
Loaded 1 password hash (dummy [N/A])
MKV start (stats=$JOHN/stats, lvl=100-200 len=6-10 pwd=25935643)

0:00:00:00 Proceeding with Markov mode 100-200:0:25935643:6-10
0:00:00:00 - Statsfile: $JOHN/stats
0:00:00:00 - Markov level: 100 - 200
0:00:00:00 - Length: 6 - 10
0:00:00:00 - Start-End: 0 - 25935643


Frank

View attachment "0001-Markov-mode-move-parameter-validation-into-new-funct.patch" of type "text/x-patch" (7888 bytes)

View attachment "0002-genmkvpwd-should-use-MAX_MKV_LVL.patch" of type "text/x-patch" (1265 bytes)

View attachment "0003-Markov-different-error-messages-for-missing-Markov-D.patch" of type "text/x-patch" (3571 bytes)

View attachment "0004-Markov-improved-logging.patch" of type "text/x-patch" (2941 bytes)

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