def verify(self, pk, M, S):
modbits = int(pk['N']).bit_length()
k = int(ceil(modbits / 8.0))
emLen = int(ceil((modbits - 1) / 8.0))
if len(S) != k:
if debug: print("Sig is %s octets long, not %" % (len(S), k))
return False
s = Conversion.OS2IP(S)
s = integer(s) % pk['N'] #Convert to modular integer
m = (s**pk['e']) % pk['N']
EM = Conversion.IP2OS(m, emLen)
if debug:
print("Verifying")
print("k =>", k)
print("emLen =>", emLen)
print("s =>", s)
print("m =>", m)
print("em =>", EM)
print("S =>", S)
return self.paddingscheme.verify(M, EM, modbits - 1)
def testIP2OSLen(self):
i = 9202000
os = Conversion.IP2OS(i, 200)
i2 = Conversion.OS2IP(os)
self.assertEqual(i, i2)
def testIP2OS(self):
#9,202,000 = (0x)8c 69 50.
os = Conversion.IP2OS(9202000)
self.assertEqual(os, b'\x8c\x69\x50')
def decrypt(self, pk, sk, c):
octetlen = int(ceil(int(pk['N']).bit_length() / 8.0))
M = (c**(sk['d'] % sk['phi_N'])) % pk['N']
os = Conversion.IP2OS(int(M), octetlen)
if debug: print("OS =>", os)
return self.paddingscheme.decode(os)
def getRandomBits(self, length):
i = randomBits(length)
len = math.ceil(length / 8)
return Conversion.IP2OS(i, len)
def getRandomBytes(self, length):
bits = length * 8
val = randomBits(bits)
return Conversion.IP2OS(val, length)
