How to make JohnTR use all of your cpu cores

Lack of time make people use available resources more efficiently . And this rule applies to me too . I`ve got a password hash to crack and can`t wait so many days for my 1.8Gh mobile CPU to try to crack it . My first idea was to look for more CPU power and speed ,something which is not much cheap if you`re looking for cutting-edge technology !

Available cpu on my notebook (Intel 1.8 Dothan) could try about ~3500 passwords per second . Damn low ! So I did a call-for-idle-cpu and got two of them . First one was AMD Athlon 5000 LD , working as fast as ~6200 c/s . Near two times faster than my own cpu , but still far away from what I`m looking for ! So I tried second cpu , Intel X5450 3Ghz . Fastest rate on this cpu with different compiles of JohnTR was a bit faster than AMD , around ~8500 c/s. I want it FASTER !

We`re living in age of multi-core processors but we rarely use all the power of our cpu . Raw JohnTR unfortunately , is not multi-core aware by default . It means that if you run it on a multi-core (2,4,8,... !) cpu JohnTR will use only ONE of cores , just like you have a normal cpu . Too much bad for us ! The Intel X5450 cpu I was using has 8 cores and I`m missing 7 of them.
Those idle cores made me remember a great projec , patching JohnTR for making it multi-core aware . It`s known as MPI Patch . MPI Patch itself is based on another project ( MPICH ) and a research work by Ryan Lim, available here .
As BindShell documentations about their MPI Patch was not much kiddy friendly , I though would worth a blog post trying to make it an easy to follow step-by-step experience for any honored multi-core cpu owner . So here it is :

JohnThe Ripper + MPI + Intel X5450 3Gh

Step One: Make sure you are ready to go for compiling few source code packages . All you need is a recent version of GCC and C++ . On the linux shell I had they were not available on fresh install , so what I did was :

yum install gcc
yum install gcc-c++.i386

Step Two: Get latest MPICH source package from here . Follow the simple extract>./configure>make>make install game . if you don`t know how to play this game , here is the instruction :

wget http://www.mcs.anl.gov/.......
tar -xf mpich2-1.0.8.tar.gz
cd mpich2-1.0.8
./configure
make
make install

Step Three: Time to get MPI armored JohnTR . Get it from BindShell project page , and note to skip the version named "....-mp8-all..." . This version is patched to handle more password hash types , but we don`t need it now . And it`s also not compiling smoothly out of the box . So get this MPI-only patched version . Let`s play above game again :

wget http://www.bindshell.net/...
tar -xf john-1.7.3.1-mpi8.tar.gz
cd john-1.7.3.1-mpi8/src/
make generic

Have my advice and use "generic" rule to compile JohnTR . Don`t ask why , it`s just better for you and works without any problem .

Step Four: So far we`ve compile MPICH and JohnTR-MPI , but we`re not ready to run yet . MPICH needs some configurations to start it`s daemon . Don`t panic, a simple single-line config file is enough to keep things working :) Here`s how to make MPI work :

echo MPD_SECRETWORD=secret > /etc/mpd.conf
chmod 600 /etc/mpd.conf
mpd --daemon

Above configuration is for the cases you`re running mpd as root (not advised!) . If you feel insecure , go read full detailed manuals of MPI project .

Step Five : Time to fire JohnTR ! Since we want to use capabilities provided by MPI interface , we should run JohnTR on top of MPI ,and that`s why JohnTR is patched ! On my test-bed (8 cores Intel) here`s how I run it :

mpirun -np 8 /root/temp/john-1.7.3.1-mpi8/run/john /root/temp/shadow

Noticed bolded parameters ? There you can adjust number of threads for MPI , or in other words , number of processor cores you want JohnTR to use for running . If you`ve got a dual-core cpu , it would be " -np 2 " and so on ...

That`s it ! But how much FASTER we`re now ? I bet you`ll be excited by results . Below are benchmark tests of running John on ONE and then on 8 cores . I`ve highlighted differences in case you``re lost in numbers.

John running on 8 cores :





John runnong on 1 core :






Using all 8 cores of test-bed cpu at clock of 3Ghz I was able to achive speed of about 70,000 tries per second , compared to out-of-box speed of ~8000 tries per second . Yes , this what I consider FAST ! My focus was gaining better speed for cracking shadow passwords, but if you`re going to crack windows (LM) dumped hashes , cracking speed is madly high . About 42 Million tries per second using all 8 cores , versus 5.4 Million tries per second for a normal JohnTR lunch against LM hashes .
Things are not going to stop here . MPI let you distribute your cracking experiences not only to multiple cores on single cpu , but to multiple cpus on networked cluster of computers . Just imagine the processing power of 5 clustered 8-cores systems running JohnTR ... o.0


Let me thank you s_hahroo_z for providing AMD processor test result , and special thanks for Mr.Hajimoradi for sharing his dusty 8 core cpu , and of course the root shell ! :)