def test_exact_data_with_data_inverse(): """The data entered is the data returned. The storing data is the exact length needed.""" test_string = "This is a test String" test_data = bytes(test_string, 'utf-8') stegs = Steganographer() stegs._header.data_len = len(test_string) blank_data = bytes(b'\x01' * len(test_string) * stegs._BYTELEN) revealed_data = stegs._reveal_data(stegs._hide_data(blank_data, test_data)) assert test_data == revealed_data
def test_hide_reveal_data_inverse(string_to_hide): """Anything hidden by _hide_data is revealed by _reveal_data.""" clean_data = bytes(b'\x01' * 5000) data_to_hide = bytes(string_to_hide, 'utf-8') stegs = Steganographer() stegs._header.data_len = len(string_to_hide.encode('utf-8')) revealed_data = stegs._reveal_data( stegs._hide_data(clean_data, data_to_hide)) assert revealed_data == data_to_hide
def test_short_data_with_data_inverse(): """When the data is too small, by a full byte, everything that can be returned is returned.""" test_string = "This is a test String" test_data = bytes(test_string, 'utf-8') stegs = Steganographer() stegs._header.data_len = len(test_string) blank_data = bytes(b'\x01' * (len(test_string) * stegs._BYTELEN - stegs._BYTELEN)) revealed_data = stegs._reveal_data(stegs._hide_data(blank_data, test_data)) assert test_data[:-1] == revealed_data
def test_retrieve_header(): """The header is retrieved as expected""" stegs = Steganographer() test_message = "12345".encode('utf-8') test_data_len = len(test_message) test_bits_used = 1 test_file_name = "test_retrieve_header.txt" test_file_name_len = len(test_file_name) test_data = bytes(b'\x01' * 1000) test_header = stegs._generate_header(test_data_len, test_bits_used, test_file_name) hidden_data = stegs._hide_data( test_data[:stegs._header.header_length * stegs._BYTELEN], test_header) hidden_data += stegs._hide_data( test_data[stegs._header.header_length * stegs._BYTELEN:], test_message) header_retrieved = stegs._retrieve_header(hidden_data) assert header_retrieved is True assert stegs._header.data_len == test_data_len assert stegs._header.bits_used == test_bits_used assert stegs._header.file_name_len == test_file_name_len assert stegs._header.file_name.decode('utf-8') == test_file_name
def test_short_partial_data_w_data_inverse(): """When the data is too small, by a half byte, everything that can be returned is returned.""" test_string = "This is a test String" test_data = bytes(test_string, 'utf-8') solution_data = bytearray(test_data) stegs = Steganographer() stegs._header.data_len = len(test_string) solution_data[ -1] = solution_data[-1] >> stegs._BYTELEN // 2 << stegs._BYTELEN // 2 blank_data = bytes( b'\x01' * (len(test_string) * stegs._BYTELEN - stegs._BYTELEN // 2)) revealed_data = stegs._reveal_data(stegs._hide_data(blank_data, test_data)) assert solution_data == revealed_data
def test_hide_data_partial(): """Will work when given a bytes object that is too short to contain the full data to be hidden.""" stegs = Steganographer() test_data = bytes(b'\x01' * stegs._BYTELEN * 3) data_to_hide = bytes('ABC', 'utf-8') stegs._header.data_len = len(data_to_hide) solution_data = bytearray(stegs._BYTELEN * 3) solution_data[1] = 1 solution_data[7] = 1 solution_data[9] = 1 solution_data[14] = 1 solution_data[17] = 1 solution_data[22] = 1 solution_data[23] = 1 # Testing when only half a byte is passed in for the data that contains the hidden text. assert stegs._hide_data(test_data[:4], data_to_hide) == solution_data[:4]
def test_hide_data(): """Will hide one bytes object inside another.""" stegs = Steganographer() test_data = bytes(b'\x01' * stegs._BYTELEN * 4) data_to_hide = bytes('ABC', 'utf-8') stegs._header.data_len = len(data_to_hide) solution_data = bytearray(stegs._BYTELEN * 4) solution_data[1] = 1 solution_data[7] = 1 solution_data[9] = 1 solution_data[14] = 1 solution_data[17] = 1 solution_data[22] = 1 solution_data[23] = 1 solution_data[24:] = b'\x01' * stegs._BYTELEN assert stegs._hide_data(test_data, data_to_hide) == solution_data