hashcat in VM
#11
Can someone help with the configuratiuon of hashcat when 3DES should find a key where K1=K3?
Or a hint ...
Thanks
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#12
to get full speedup the best way would probably be:

(note: I'm assuming each key is 8 bytes; adapt as needed)

1. create a wordlist with all combinations of K1 (or a reproducable subset thereof if the whole space is too large)
2. create a ruleset which appends the bytes for K2 (you can chain rulesets, hence you only need a single rules file with one rule for each byte and use that eight times)
3. as a single final rule(set) use d]]]]]]]] (this will duplicate the whole candidate (K1+K2) and then remove K2 at the end)

so your files might look like this:

K1.txt (use --hex-wordlist)
Code:
0000000000000000
0100000000000000
0200000000000000

ffffffffffffffff

K2.rule
Code:
$\x00
$\x01

$\xff

final.rule
Code:
d]]]]]]]]

modifying the existing kernel to handle everything would be a nicer solution, but also not as easy to pull off.
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#13
The problem here might be that you probably need to use -S or pipe or otherwise the plains will be rejected already on host (you may be able to work around it, by always providing 24 bytes, but that's quite ugly).

The best of course would be to change the module and kernel to just set K1=K3 in the kernel and allow 16 bytes plains in host/module.

Another way of the rule would be just to use this:
Code:
y8 {{{{{{{{
copy the first block of 8 bytes and rotate it to the end (8 rotates)

but again, the plains will be already be rejected on host because the 16 bytes (2 blocks) are too short for 24 bytes "keys"
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