Image.ReadUInt16 C# (CSharp) Method

    static ushort ReadUInt16(this Stream stream)
    {
        return (ushort)(stream.ReadByte()
                        | (stream.ReadByte() << 8));
    }

        protected override (ulong, ulong) ConsiderCode(ulong loc, ulong globalOffset)
        {
            ulong  funcPtr, metadata, code;
            ushort opcode;

            // Variant 1

            // Assembly bytes to search for at start of each function
            var bytes = new byte[] { 0x6A, 0x00, 0x6A, 0x00, 0x68 };

            Image.Position = (long)loc;
            var buff = Image.ReadBytes(5);

            if (bytes.SequenceEqual(buff))
            {
                // Next 4 bytes are the function pointer being pushed onto the stack
                funcPtr = Image.ReadUInt32();

                // Start of next instruction
                if (Image.ReadByte() != 0xB9)
                {
                    return(0, 0);
                }

                // Jump to Il2CppCodegenRegistration
                Image.Position = (uint)Image.MapVATR(funcPtr) + 6;
                metadata       = Image.ReadUInt32();
                Image.Position = (uint)Image.MapVATR(funcPtr) + 11;
                code           = Image.ReadUInt32();
                return(code, metadata);
            }

            // Variant 2
            bytes          = new byte[] { 0x55, 0x89, 0xE5, 0x53, 0x83, 0xE4, 0xF0, 0x83, 0xEC, 0x20, 0xE8, 0x00, 0x00, 0x00, 0x00, 0x5B };
            Image.Position = (long)loc;
            buff           = Image.ReadBytes(16);
            if (!bytes.SequenceEqual(buff))
            {
                return(0, 0);
            }

            Image.Position += 8;
            funcPtr         = Image.MapVATR(Image.ReadUInt32() + globalOffset);
            if ((long)funcPtr > Image.Stream.BaseStream.Length)
            {
                return(0, 0);
            }

            // Extract Metadata pointer
            // An 0x838D opcode indicates LEA (no indirection)
            Image.Position = (long)(funcPtr + 0x20);
            opcode         = Image.ReadUInt16();
            metadata       = Image.ReadUInt32() + globalOffset;

            // An 8x838B opcode indicates MOV (pointer indirection)
            if (opcode == 0x838B)
            {
                Image.Position = (uint)Image.MapVATR(metadata);
                metadata       = Image.ReadUInt32();
            }

            // Repeat the same logic for extracting the Code pointer
            Image.Position = (long)(funcPtr + 0x2A);
            opcode         = Image.ReadUInt16();
            code           = Image.ReadUInt32() + globalOffset;

            if (opcode == 0x838B)
            {
                Image.Position = (uint)Image.MapVATR(code);
                code           = Image.ReadUInt32();
            }

            return(code, metadata);
        }