#coding=utf-8 SubBytes = [99, 124, 119, 123, 242, 107, 111, 197, 48, 1, 103, 43, 254, 215, 171, 118, 202, 130, 201, 125, 250, 89, 71, 240, 173, 212, 162, 175, 156, 164, 114, 192, 183, 253, 147, 38, 54, 63, 247, 204, 52, 165, 229, 241, 113, 216, 49, 21, 4, 199, 35, 195, 24, 150, 5, 154, 7, 18, 128, 226, 235, 39, 178, 117, 9, 131, 44, 26, 27, 110, 90, 160, 82, 59, 214, 179, 41, 227, 47, 132, 83, 209, 0, 237, 32, 252, 177, 91, 106, 203, 190, 57, 74, 76, 88, 207, 208, 239, 170, 251, 67, 77, 51, 133, 69, 249, 2, 127, 80, 60, 159, 168, 81, 163, 64, 143, 146, 157, 56, 245, 188, 182, 218, 33, 16, 255, 243, 210, 205, 12, 19, 236, 95, 151, 68, 23, 196, 167, 126, 61, 100, 93, 25, 115, 96, 129, 79, 220, 34, 42, 144, 136, 70, 238, 184, 20, 222, 94, 11, 219, 224, 50, 58, 10, 73, 6, 36, 92, 194, 211, 172, 98, 145, 149, 228, 121, 231, 200, 55, 109, 141, 213, 78, 169, 108, 86, 244, 234, 101, 122, 174, 8, 186, 120, 37, 46, 28, 166, 180, 198, 232, 221, 116, 31, 75, 189, 139, 138, 112, 62, 181, 102, 72, 3, 246, 14, 97, 53, 87, 185, 134, 193, 29, 158, 225, 248, 152, 17, 105, 217, 142, 148, 155, 30, 135, 233, 206, 85, 40, 223, 140, 161, 137, 13, 191, 230, 66, 104, 65, 153, 45, 15, 176, 84, 187, 22] InvSubBytes = [82, 9, 106, 213, 48, 54, 165, 56, 191, 64, 163, 158, 129, 243, 215, 251, 124, 227, 57, 130, 155, 47, 255, 135, 52, 142, 67, 68, 196, 222, 233, 203, 84, 123, 148, 50, 166, 194, 35, 61, 238, 76, 149, 11, 66, 250, 195, 78, 8, 46, 161, 102, 40, 217, 36, 178, 118, 91, 162, 73, 109, 139, 209, 37, 114, 248, 246, 100, 134, 104, 152, 22, 212, 164, 92, 204, 93, 101, 182, 146, 108, 112, 72, 80, 253, 237, 185, 218, 94, 21, 70, 87, 167, 141, 157, 132, 144, 216, 171, 0, 140, 188, 211, 10, 247, 228, 88, 5, 184, 179, 69, 6, 208, 44, 30, 143, 202, 63, 15, 2, 193, 175, 189, 3, 1, 19, 138, 107, 58, 145, 17, 65, 79, 103, 220, 234, 151, 242, 207, 206, 240, 180, 230, 115, 150, 172, 116, 34, 231, 173, 53, 133, 226, 249, 55, 232, 28, 117, 223, 110, 71, 241, 26, 113, 29, 41, 197, 137, 111, 183, 98, 14, 170, 24, 190, 27, 252, 86, 62, 75, 198, 210, 121, 32, 154, 219, 192, 254, 120, 205, 90, 244, 31, 221, 168, 51, 136, 7, 199, 49, 177, 18, 16, 89, 39, 128, 236, 95, 96, 81, 127, 169, 25, 181, 74, 13, 45, 229, 122, 159, 147, 201, 156, 239, 160, 224, 59, 77, 174, 42, 245, 176, 200, 235, 187, 60, 131, 83, 153, 97, 23, 43, 4, 126, 186, 119, 214, 38, 225, 105, 20, 99, 85, 33, 12, 125] null_char = 0 block_size = 16 keys = [35, 54, 46, 49, 58, 45, 34, 0, 52, 0, 38, 41, 39, 47, 49, 47] enc_data = [13, 84, 192, 126, 130, 148, 115, 248, 109, 253, 42, 181, 128, 21, 115, 30, 96, 90, 109, 242, 36, 113, 33, 63, 247, 21, 202, 79, 97, 202, 67, 189] list2hexline = lambda data: " ".join([hex(ch)[2:].zfill(2) for ch in data]) def dec2poly(num): res = [] num = bin(num)[2:] for offset, ch in enumerate(num): if ch == '1': res.append(len(num)-offset-1) return res #Cyclic shift function| direction: 1 - right, -1 - left def cyclic_shift(data, shift, direction=1): shift %= len(data) return data[direction*-shift:] + data[:direction*-shift] #XOR elements def xor(first, second): result_size = max(len(first), len(second)) first, second = map(lambda n: [0, ]*(result_size - len(n)) + n, [first, second]) return map(lambda n: (n[0] ^ n[1]), zip(first, second)) #Addition to the block size | len(keyword) = 0 (mod key_block_len) def check_key(key): return key + [null_char, ] * ((block_size - len(key)) % block_size) #Generate round keys def gen_round_keys(): global keys keys = check_key(keys) keys = [keys[offset:offset+4] for offset in xrange(0, len(keys), 4)] while len(keys) < 16: curr_key_index = len(keys) prev_key = keys[curr_key_index-1] if curr_key_index % 4 == 0: prev_key = xor(substitute(cyclic_shift(prev_key, 1, -1), SubBytes), [2**(curr_key_index/4-1), ]) keys.append(xor(prev_key, keys[curr_key_index-4])) #Multiplication number and const def poly_mul(number, poly_const): result = 0 for pw in poly_const: result ^= number << pw print "POLY_MUL: (%s == %s) * %s = %s" % (number, dec2poly(number), poly_const, dec2poly(result)) return result def poly_mod(number, mod=283): while number > 255: lst = number xor_num = mod << len(bin(number)[2:])-len(bin(mod)[2:]) number ^= xor_num print "...POLY_MOD: %s ^ %s = %s" % (dec2poly(lst), dec2poly(xor_num), dec2poly(number)) print "POLY_MOD_RES: %s = %s\n" % (dec2poly(number), number) return number #SybBytes def substitute(index, table): return [table[num] for num in index] def step_InvMixColumn(block): poly_const = [[3, 2, 1], [3, 1, 0], [3, 2, 0], [3, 0]] res_block = [] for index, line in enumerate(block): tmp = cyclic_shift(poly_const, index) res = [] for j, ch in enumerate(line): temptemp = map(lambda (bl, const): poly_mod(poly_mul(bl, const)), [(block[s][j], tmp[s]) for s in range(4)]) value_res = reduce(lambda prev_a, prev_b: prev_a ^ prev_b, temptemp) print "XOR_ELEMS(%s) = %s" % (temptemp, value_res) print "=====\n\n" res.append(value_res) res_block.append(res) return res_block def step_InvSubBytes(block): return [substitute(line, InvSubBytes) for index, line in enumerate(block)] def step_InvShiftRow(block): return [cyclic_shift(line, index) for index, line in enumerate(block)] def step_AddRoundKey(block, shift_key): return [xor(line, keys[shift_key+index]) for index, line in enumerate(block)] def main(): global keys gen_round_keys() print ">>>ROUND KEYS:" for ind, r_key in enumerate(keys): print "w[%s]: %s" % (ind, list2hexline(r_key)) keys = keys[:8] + step_InvMixColumn(keys[8:12]) + keys[12:] keys = keys[:4] + step_InvMixColumn(keys[4:8]) + keys[8:] print "\n>>>\?ROUND KEYS AFTER InvMixColumn | replacement on the direct order" for ind, r_key in enumerate(keys): print "w[%s]: %s" % (ind, list2hexline(r_key)) for block_num in range(0, len(enc_data), 16): print "\n>>>BLOCK:\n" block = [enc_data[sbi:sbi+4] for sbi in xrange(block_num, block_num+block_size, 4)] block = step_AddRoundKey(block, 12) print "Step1:\n%s" % "\n".join(map(list2hexline, block)) block = step_InvSubBytes(block) print "Step2:\n%s" % "\n".join(map(list2hexline, block)) block = step_InvShiftRow(block) print "Step3:\n%s" % "\n".join(map(list2hexline, block)) block = step_InvMixColumn(block) print "Step4:\n%s" % "\n".join(map(list2hexline, block)) block = step_AddRoundKey(block, 8) print "Step5:\n%s" % "\n".join(map(list2hexline, block)) block = step_InvSubBytes(block) print "Step6:\n%s" % "\n".join(map(list2hexline, block)) block = step_InvShiftRow(block) print "Step7:\n%s" % "\n".join(map(list2hexline, block)) block = step_InvMixColumn(block) print "Step8:\n%s" % "\n".join(map(list2hexline, block)) block = step_AddRoundKey(block, 4) print "Step9:\n%s" % "\n".join(map(list2hexline, block)) block = step_InvSubBytes(block) print "Step10:\n%s" % "\n".join(map(list2hexline, block)) block = step_InvShiftRow(block) print "Step11:\n%s" % "\n".join(map(list2hexline, block)) block = step_AddRoundKey(block, 0) print "Step12:\n%s" % "\n".join(map(list2hexline, block)) if __name__ == "__main__": main()