variable friction coefficient based on stress

Hi all, I'm modeling a soil steel interaction in abaqus explicit. The two surfaces are element bases sets with the surface-to-surface contact (explicit). The interaction properties are hard contact with Coulomb friction with a friction coefficient. The soil part is governed with a VUMAT I wrote. I need to make the contact friction coefficient to be variable based on Lode angle or J3 (stress invariant) or one of my state variables in my VUMAT. I was hoping I could do that by using the VFRIC_COEF subroutine; however, I do not know how to access stress tensor or state variables for the elements associated with a particular point on contact. Is this even possible with the way contacts work? I'd appreciate any help. Thanks