Inner Product/Matrix Product Node

There should be a node with three input vectors and an input reference vector. Imagine the inputs:
[ref]
[c1]
[c2]
[c3]
[c4]


Outputting a vector which is: c1*ref.r + c2*ref.g + c3*ref.b + c1*ref.a
It's *very* similar to the dot product. I believe they are both Inner products, so perhaps this node could be called inner product? Or is it a matrix product?