In this paper, photonic crystal structures are proposed to design configurable all-optical logic gates. These structures offer XOR/AND and XNOR/NAND logic operations which provide two logic functions in an output port by means of a control signal that provides more flexibility in circuit design procedure. Also, the proposed structures offer a half adder (AND/XOR) and its inverted logic (NAND/ XNOR). The proposed structures include a nonlinear directional coupler and Y-junctions. In the proposed structures, the nonlinear directional coupler, which consists of nonlinear rods made of silicon nano-crystals, is used to provide a phase shifter for different input powers. Finite difference time domain and plane wave expansion methods are used to evaluate the proposed structures. Effects of variations in wavelength, refractive index and radius of rods on the performance of the proposed structures are studied which indicate the robustness of the proposed structures against process variation. Simulation results show that the switching power and bit rateof the proposed structures are 3 W and 1 Tbits/s respectively.