John the ripper multiple mask attack

Question

I am going to use John the Ripper on a multi-core server to crack about 400 Windows NT hashes. Depending on my CPU capacities I want to check all passwords that satisfy following masks:

?1?1?1?1?1?1?1 --min-len=1

?2?2?2?2?2?2?2?2 --min-len=8

?3?3?3?3?3?3?3?3?3 --min-len=9

?4?4?4?4?4?4?4?4?4?4 --min-len=10

where:

-1: ?l?u?d?s

-2: ?l?u?d

-3: ?l?d

-4: ?l

I have 16 cores (32 threads) so I am planning to run using --fork=16 or --fork=32. The only part I have not find is how to run more masks in one command.

PS: I have to use JtR, not HashCat.

Answer 1

I'm not aware of a way to pass a list of masks to john as a single command (in the way that hashcat allows).

The best you can do today is to use the custom placeholder syntax (-1, -2, etc.) just as you've done, and run each command separately (which could be combined into a single run with a batch or command file).

(And if your limitation on hashcat is just that you can't use OpenCL, this attack is simple enough that you could use hashcat-legacy (download here), which is CPU-only.)