import time import unittest from urh.signalprocessing.Encoding import Encoding from urh.util import util from urh.util.GenericCRC import GenericCRC from urh.util.WSPChecksum import WSPChecksum class TestCRC(unittest.TestCase): def test_crc(self): # http://depa.usst.edu.cn/chenjq/www2/software/crc/CRC_Javascript/CRCcalculation.htm # CRC-16: polynomial="16_standard", start_value = False, final_xor = False, reverse_polynomial=False, reverse_all=False # CRC-16-CCITT: polynomial="16_ccitt", start_value = False, final_xor = False, reverse_polynomial=False, reverse_all=False # http://www.lammertbies.nl/comm/info/crc-calculation.html <- Fehler # CRC-16: polynomial="16_standard", start_value = False, final_xor = False, reverse_polynomial=False, reverse_all=False c = GenericCRC(polynomial=WSPChecksum.CRC_8_POLYNOMIAL) e = Encoding() bitstr = ["010101010110100111011010111011101110111011100110001011101010001011101110110110101101", "010101010110101001101110111011101110111011100110001011101010001011101110110111100101", "010101010110100111010010111011101110111011100110001011101010001011101110110110100101"] expected = ["78", "c9", "f2"] for value, expect in zip(bitstr, expected): nv = "" for i in range(0, len(value)): if value[i] == "1": nv += "0" else: nv += "1" self.assertEqual(util.bit2hex(c.crc(e.str2bit(value[4:-8]))), expect) def test_crc8(self): messages = ["aabbcc", "abcdee", "dacafe"] expected = ["7d", "24", "33"] crc = GenericCRC(polynomial=GenericCRC.DEFAULT_POLYNOMIALS["8_ccitt"]) for msg, expect in zip(messages, expected): bits = util.hex2bit(msg) self.assertEqual(util.bit2hex(crc.crc(bits)), expect) def test_different_crcs(self): c = GenericCRC(polynomial="16_standard", start_value=False, final_xor=False, reverse_polynomial=False, reverse_all=False, lsb_first=False, little_endian=False) bitstring_set = [ "101001001010101010101011101111111000000000000111101010011101011", "101001001010101101111010110111101010010110111010", "00000000000000000000000000000000100000000000000000000000000000000001111111111111", "1111111111111111111111111111111110111111111111111111110111111111111111110000000000" "1"] for j in c.DEFAULT_POLYNOMIALS: c.polynomial = c.choose_polynomial(j) for i in bitstring_set: # Standard crc_new = c.crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_new, crc_old) # Special final xor c.final_xor = c.str2bit("0000111100001111") crc_new = c.crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_new, crc_old) c.final_xor = [False] * 16 # Special start value c.start_value = c.str2bit("1010101010101010") crc_new = c.crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_new, crc_old) c.start_value = [False] * 16 # reverse_polynomial c.reverse_polynomial = True crc_new = c.crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_new, crc_old) c.reverse_polynomial = False # lsb_first c.lsb_first = True crc_new = c.crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_new, crc_old) c.lsb_first = False # little_endian c.little_endian = True crc_new = c.crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_new, crc_old) c.little_endian = False # reverse all c.reverse_all = True crc_new = c.crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_new, crc_old) c.reverse_all = False def test_cache(self): c = GenericCRC(polynomial="16_standard", start_value=False, final_xor=False, reverse_polynomial=False, reverse_all=False, lsb_first=False, little_endian=False) c.calculate_cache(8) self.assertEqual(len(c.cache), 256) def test_different_crcs_fast(self): c = GenericCRC(polynomial="16_standard", start_value=False, final_xor=False, reverse_polynomial=False, reverse_all=False, lsb_first=False, little_endian=False) bitstring_set = [ "10101010", "00000001", "000000010", "000000011", "0000000100000001", "101001001010101010101011101111111000000000000111101010011101011", "101001001010101101111010110111101010010110111010", "00000000000000000000000000000000100000000000000000000000000000000001111111111111", "1111111111111111111111111111111110111111111111111111110111111111111111110000000000" "1"] for j in c.DEFAULT_POLYNOMIALS: c.polynomial = c.choose_polynomial(j) for i in bitstring_set: for cache in [8, 4, 7, 12, 16]: c.calculate_cache(cache) # Standard crc_new = c.cached_crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_old, crc_new) # Special final xor c.final_xor = c.str2bit("0000111100001111") crc_new = c.cached_crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_old, crc_new) c.final_xor = [False] * 16 # Special start value c.start_value = c.str2bit("1010101010101010") crc_new = c.cached_crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_old, crc_new) c.start_value = [False] * 16 # little_endian c.little_endian = True crc_new = c.cached_crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_old, crc_new) c.little_endian = False # reverse all c.reverse_all = True crc_new = c.cached_crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_old, crc_new) c.reverse_all = False # reverse_polynomial # We need to clear the cache before and after c.cache = [] # c.reverse_polynomial = True crc_new = c.cached_crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_old, crc_new) c.reverse_polynomial = False # c.cache = [] # TODO: Does only work for cachesize = 8 # lsb_first c.calculate_cache(8) c.lsb_first = True crc_new = c.cached_crc(c.str2bit(i)) crc_old = c.reference_crc(c.str2bit(i)) self.assertEqual(crc_old, crc_new) c.lsb_first = False def test_reverse_engineering(self): c = GenericCRC(polynomial="16_standard", start_value=False, final_xor=False, reverse_polynomial=False, reverse_all=False, lsb_first=False, little_endian=False) bitstring_set = [ "1110001111001011100010000101010100000010110111000101100010100100111110111101100110110111011001010010001011101010", "1110010011001011100010000101010100000010110111000101100010100100111110111101100110110111011001010010001011101010", "1110010111001011100010000101010100000010110111000101100010100100111110111101100110110111011001010010001011101010", "1110011011001011100010000101010100000010110111000101100010100100111110111101100110110111011001010010001011101010"] bitset = [] crcset = [] for i in bitstring_set: tmp = c.str2bit(i) bitset.append(tmp) crcset.append(c.crc(tmp)) polynomial = c.reverse_engineer_polynomial(bitset, crcset) if polynomial: self.assertEqual(c.bit2str(polynomial), "1000000000000101") self.assertEqual(util.bit2hex(polynomial), "8005") def test_not_aligned_data_len(self): c = GenericCRC(polynomial="16_standard", start_value=False, final_xor=False, reverse_polynomial=False, reverse_all=False, lsb_first=False, little_endian=False) polynomials = ["8_standard", "16_standard", "16_ccitt", "16_dnp"] crcs = {"8_standard": 0xd5, "16_standard": 0x8005, "16_ccitt": 0x1021, "16_dnp": 0x3d65} for j in polynomials: c.polynomial = c.choose_polynomial(j) inpt = "1" for i in range(0, 32): val = c.bit2int(c.crc(c.str2bit(inpt))) self.assertEqual(val, crcs[j]) inpt = "0" + inpt def test_bruteforce_parameters_and_data_range(self): c = GenericCRC(polynomial="16_ccitt", start_value=False, final_xor=False, reverse_polynomial=False, reverse_all=False, lsb_first=False, little_endian=False) inpt = "101010101010101010000000111000000000000011100000001011010010110100000000111000000101001010000100000000000100111001111110010000000011011111111001001101100001100010100000000000111011110100010" vrfy_crc = "0011101111010001" result = c.bruteforce_parameters_and_data_range(c.str2arr(inpt), len(inpt)-len(vrfy_crc)-1) self.assertEqual(result, (2, 84, 172)) self.assertEqual(vrfy_crc, c.bit2str(c.crc(c.str2arr(inpt[result[1]:result[2]])))) def test_bruteforce_parameters_and_data_range_improved(self): c = GenericCRC(polynomial="16_ccitt", start_value=False, final_xor=False, reverse_polynomial=False, reverse_all=False, lsb_first=False, little_endian=False) inpt = "101010101010101010000000111000000000000011100000001011010010110100000000111000000101001010000100000000000100111001111110010000000011011111111001001101100001100010100000000000111011110100010" vrfy_crc = "0011101111010001" t1 = 0 runs = 100 for i in range(0, runs): t = time.time() result = c.bruteforce_parameters_and_data_range(c.str2arr(inpt), len(inpt)-len(vrfy_crc)-1) t1 += time.time() - t # print(result, c.bit2str(c.crc(c.str2arr(inpt[result[1]:result[2]])))) self.assertEqual(result[0], 2) # Parameters = 2 self.assertEqual(result[1], len(inpt) - 1 - 16 - 88) # start of datarange self.assertEqual(result[2], len(inpt) - 1 - 16) # end of datarange inpt = "0" + inpt if i % 2 == 0 else "1" + inpt # print("Performance:", t1/runs) self.assertLess(t1 / runs, 0.1) # Should be faster than 100ms in average def test_adaptive_crc_calculation(self): c = GenericCRC(polynomial="16_ccitt", start_value=False, final_xor=False, reverse_polynomial=False, reverse_all=False, lsb_first=False, little_endian=False) inpt1 = "10101010101010" inpt2 = "1010101010101001" crc1 = c.crc(c.str2arr(inpt1)) crc2 = c.crc(c.str2arr(inpt2)) # Compute crc2 from crc1 in a faster way # Note: In general only forward direction delta = "01" c.start_value = crc1 crcx = c.crc(c.str2arr(delta)) self.assertEqual(crcx, crc2)