Parallel programming ( Cuda, OpenCL )

I have a project written by Java.
This project is very simple. Hashing with Sha256, and curve25519.
ex) password = name123
name123 —>hashing with sha256—>hashing with curve25519—>result
I need more than million calculating power.
I don’t care about language if program works. ( python, c++, c, java etc)
Maybe openCL or cuda or GPGPU is required ( in my opinion )