CRCPOLYNOMIAL = 0xEDB88320
crctable = [0 for x in range(256)]
def create_table():
for i in range(256):
crcreg = i
for _ in range(8):
if (crcreg & 1) != 0:
crcreg = CRCPOLYNOMIAL ^ (crcreg >> 1)
else:
crcreg = crcreg >> 1
crctable[i] = crcreg
def crc32(string):
crcstart = 0xFFFFFFFF
for i in range(len(str(string))):
index = (crcstart ^ ord(str(string)[i])) & 255
crcstart = (crcstart >> 8) ^ crctable[index]
return crcstart
def crc32_last_index(string):
crcstart = 0xFFFFFFFF
for i in range(len(str(string))):
index = (crcstart ^ ord(str(string)[i])) & 255
crcstart = (crcstart >> 8) ^ crctable[index]
return index
def get_crc_index(t):
for i in range(256):
if crctable[i] >> 24 == t:
return i
return -1
def deep_check(i, index):
string = ""
tc=0x00
hashcode = crc32(i)
tc = hashcode & 0xff ^ index[2]
if not (tc <= 57 and tc >= 48):
return [0]
string += str(tc - 48)
hashcode = crctable[index[2]] ^ (hashcode >>8)
tc = hashcode & 0xff ^ index[1]
if not (tc <= 57 and tc >= 48):
return [0]
string += str(tc - 48)
hashcode = crctable[index[1]] ^ (hashcode >> 8)
tc = hashcode & 0xff ^ index[0]
if not (tc <= 57 and tc >= 48):
return [0]
string += str(tc - 48)
hashcode = crctable[index[0]] ^ (hashcode >> 8)
return [1, string][/size]
[size=4]
[/size]
[size=4]def getuid(string):
create_table()
index = [0 for x in range(4)]
i = 0
ht = int(f"0x{string}", 16) ^ 0xffffffff
for i in range(3,-1,-1):
index[3-i] = get_crc_index(ht >> (i*8))
snum = crctable[index[3-i]]
ht ^= snum >> ((3-i)*8)
for i in range(100000000):
lastindex = crc32_last_index(i)
if lastindex == index[3]:
deepCheckData = deep_check(i, index)
if deepCheckData[0]:
break
if i == 100000000:
return -1
return f"{i}{deepCheckData[1]}"
[复制链接]
发表于 2020-7-31 23:11
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发表于 2020-7-31 23:27
