USER DEFINED

Hi:

 I am simulating a projectile impact on a plate and using LS - DYNA for the same. 

I have to use Barlat's anistropic plasticity model with the Johnson Cook Failure Criterion.

Now, Although Barlat's Model is in built into LS DYNA, how do I implement JC Failure criterion ? Is there a feature of User defined failure criterion in DYNA ?

If not, Is implementing a UMAT consisting of Barlat's consitutive eqn and JC failure criterion the only other option ?

Thank You,