Created
May 24, 2013 15:41
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Simple MD4 digest implementation in pure Python
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#!/usr/bin/env python | |
import struct | |
def leftrotate(i, n): | |
return ((i << n) & 0xffffffff) | (i >> (32 - n)) | |
def F(x,y,z): | |
return (x & y) | (~x & z) | |
def G(x,y,z): | |
return (x & y) | (x & z) | (y & z) | |
def H(x,y,z): | |
return x ^ y ^ z | |
class MD4(object): | |
def __init__(self, data=""): | |
self.remainder = data | |
self.count = 0 | |
self.h = [ | |
0x67452301, | |
0xefcdab89, | |
0x98badcfe, | |
0x10325476 | |
] | |
def _add_chunk(self, chunk): | |
self.count += 1 | |
X = list( struct.unpack("<16I", chunk) + (None,) * (80-16) ) | |
h = [x for x in self.h] | |
# Round 1 | |
s = (3,7,11,19) | |
for r in xrange(16): | |
i = (16-r)%4 | |
k = r | |
h[i] = leftrotate( (h[i] + F(h[(i+1)%4], h[(i+2)%4], h[(i+3)%4]) + X[k]) % 2**32, s[r%4] ) | |
# Round 2 | |
s = (3,5,9,13) | |
for r in xrange(16): | |
i = (16-r)%4 | |
k = 4*(r%4) + r//4 | |
h[i] = leftrotate( (h[i] + G(h[(i+1)%4], h[(i+2)%4], h[(i+3)%4]) + X[k] + 0x5a827999) % 2**32, s[r%4] ) | |
# Round 3 | |
s = (3,9,11,15) | |
k = (0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15) #wish I could function | |
for r in xrange(16): | |
i = (16-r)%4 | |
h[i] = leftrotate( (h[i] + H(h[(i+1)%4], h[(i+2)%4], h[(i+3)%4]) + X[k[r]] + 0x6ed9eba1) % 2**32, s[r%4] ) | |
for i,v in enumerate(h): | |
self.h[i] = (v + self.h[i]) % 2**32 | |
def add(self, data): | |
message = self.remainder + data | |
r = len(message) % 64 | |
if r != 0: | |
self.remainder = message[-r:] | |
else: | |
self.remainder = "" | |
for chunk in xrange(0, len(message)-r, 64): | |
self._add_chunk( message[chunk:chunk+64] ) | |
return self | |
def finish(self): | |
l = len(self.remainder) + 64 * self.count | |
self.add( "\x80" + "\x00" * ((55 - l) % 64) + struct.pack("<Q", l * 8) ) | |
out = struct.pack("<4I", *self.h) | |
self.__init__() | |
return out | |
if __name__=="__main__": | |
test = ( | |
("", "31d6cfe0d16ae931b73c59d7e0c089c0"), | |
("a", "bde52cb31de33e46245e05fbdbd6fb24"), | |
("abc", "a448017aaf21d8525fc10ae87aa6729d"), | |
("message digest", "d9130a8164549fe818874806e1c7014b"), | |
("abcdefghijklmnopqrstuvwxyz", "d79e1c308aa5bbcdeea8ed63df412da9"), | |
("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789", "043f8582f241db351ce627e153e7f0e4"), | |
("12345678901234567890123456789012345678901234567890123456789012345678901234567890", "e33b4ddc9c38f2199c3e7b164fcc0536") | |
) | |
md = MD4() | |
for t, h in test: | |
md.add(t) | |
d = md.finish() | |
if d == h.decode("hex"): | |
print "pass" | |
else: | |
print "FAIL: {0}: {1}\n\texpected: {2}".format(t, d.encode("hex"), h) |
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Converted to python3: https://gist.github.com/BenWiederhake/eb6dfc2c31d3dc8c34508f4fd091cea9