John the Ripper Multithreaded Multicore How-To | Linux

By | 2013/01/29

John the Ripper must be compiled from source to enable multithreaded support as well to gain the added features of the jumbo patch. It’s not that hard and I’ll show you how!


1. Grab latest patched jumbo version that includes lots of goodies:

$ wget http://openwall.com/john/g/john-1.7.9-jumbo-7.tar.bz2

2. Extract

$ tar xvf john-1.7.9-jumbo-7.tar.bz2

3. Change to the /src directory

$ cd john-1.7.9-jumbo-7/src/

4. Edit the Makefile to enable multi-threaded capabilities.

$ nano Makefile

Uncomment these lines as follows:

OMPFLAGS =
# gcc with OpenMP
OMPFLAGS = -fopenmp
OMPFLAGS = -fopenmp -msse2

5. For this next step, you will want to specify the target system. To see available targets, type

$ make

I’m on x86_64 (i5 750) so I’m going to use linux-x86-64-native.

$ make linux-x86-64-native

6. When complete, binaries are available under the /run directory.

$ cd ../run

To run a benchmark on your system, type:

$ ./john --test

Cracking MD5 via brute force is now done much faster!

Where file.txt is:

Bob:7c6a180b36896a0a8c02787eeafb0e4c

Try this:

$ ./john --format:raw-MD5 ../../file.txt 
Loaded 1 password hash (Raw MD5 [128/128 SSE2 intrinsics 12x])
password1        (Bob)

Hack on,