require "rex/text"

module Rex
module Proto
module DCERPC
class NDR


    # Provide padding to align the string to the 32bit boundary
    def self.align(string)
        return "\x00" * ((4 - (string.length & 3)) & 3)
    end
   
    # Encode a 4 byte long
    # use to encode:
    #       long element_1;
    def self.long(string)
        return [string].pack('V')
    end
    
    # Encode a 2 byte short
    # use to encode:
    #       short element_1;
    def self.short(string)
        return [string].pack('v')
    end
    
    # Encode a single byte
    # use to encode:
    #       byte element_1;
    def self.byte(string)
        return [string].pack('c')
    end
   
    # Encode a byte array
    # use to encode:
    #       char  element_1
    def self.UniConformantArray(string)
        return long(string.length) + string + align(string)
    end

    # Encode a string
    # use to encode:
    #       w_char *element_1;
    def self.UnicodeConformantVaryingString(string)
        string += "\x00" # null pad
        return long(string.length) + long(0) + long(string.length) + Rex::Text.to_unicode(string) + align(Rex::Text.to_unicode(string))
    end
    
    # Encode a string that is already unicode encoded
    # use to encode:
    #       w_char *element_1;
    def self.UnicodeConformantVaryingStringPreBuilt(string)
        # if the string len is odd, thats bad!
        if string.length % 2 > 0
            string += "\x00"
        end
        len = string.length / 2;
        return long(len) + long(0) + long(len) + string + align(string)
    end

end
end
end
end