def validate(message, digest):
return challenge28.authSHA1(key, message) == digest
def validate(message, digest):
return challenge28.authSHA1(key, message) == digest
s += b'\x80'
s += b'\x00' * ((56 - (len(s) % 64)) % 64)
s += struct.pack('>Q', l)
return s
keylen = randint(0, 100)
key = get_random_bytes(keylen)
def validate(message, digest):
return challenge28.authSHA1(key, message) == digest
message = b'comment1=cooking%20MCs;userdata=foo;comment2=%20like%20a%20pound%20of%20bacon'
messageDigest = challenge28.authSHA1(key, message)
def forgeHash(keylen, message, digest, suffix):
paddedForgedMessageWithKey = padSHA1(key + message) + suffix
forgedMessage = paddedForgedMessageWithKey[keylen:]
h = struct.unpack('>5I', digest)
forgedDigest = challenge28.SHA1(suffix, h[0], h[1], h[2], h[3], h[4],
len(paddedForgedMessageWithKey) *
8).digest()
return (forgedMessage, forgedDigest)
def forgeValidatingHash(maxkeylen, message, digest, suffix):
for i in range(maxkeylen):
(forgedMessage, forgedDigest) = forgeHash(i, message, digest, suffix)
def padSHA1(s):
l = len(s) * 8
s += b'\x80'
s += b'\x00' * ((56 - (len(s) % 64)) % 64)
s += struct.pack('>Q', l)
return s
keylen = random.randint(0, 100)
key = util.randbytes(keylen)
def validate(message, digest):
return challenge28.authSHA1(key, message) == digest
message = b'comment1=cooking%20MCs;userdata=foo;comment2=%20like%20a%20pound%20of%20bacon'
messageDigest = challenge28.authSHA1(key, message)
def forgeHash(keylen, message, digest, suffix):
paddedForgedMessageWithKey = padSHA1(key + message) + suffix
forgedMessage = paddedForgedMessageWithKey[keylen:]
h = struct.unpack('>5I', digest)
forgedDigest = challenge28.SHA1(suffix, h[0], h[1], h[2], h[3], h[4], len(paddedForgedMessageWithKey) * 8).digest()
return (forgedMessage, forgedDigest)
def forgeValidatingHash(maxkeylen, message, digest, suffix):
for i in range(maxkeylen):
(forgedMessage, forgedDigest) = forgeHash(i, message, digest, suffix)
if validate(forgedMessage, forgedDigest):
return(forgedMessage, forgedDigest)
raise Exception('unexpected')
