def decrypt(c): global p, q, SK if not check_state(): return e1 = SK[1] % (p - 1) c1 = exp.fast(c, e1, p) e2 = SK[1] % (q - 1) c2 = exp.fast(c, e2, q) ext = gcd.extended(p, q) return (c1 * ext[4] * q + c2 * ext[3] * p) % SK[0]
def encrypt(m): global PK if not check_state(): return return exp.fast(m, PK[1], PK[0])
def fermat_test(base, prime):
p1 = prime - 1
if exp.fast(base, p1, prime) == 1:
return True
else:
return False
def dec_string():
global SK, p, q
if not check_state():
return
ctext = STR.hex_to_int(base64.b64decode(input("Encrypted message: ")))
size = STR.modSize(SK[0])
output = ""
while ctext:
aux3 = STR.list2Int(ctext[:size + 2])
assert aux3 < SK[0]
c1 = exp.fast(aux3, SK[1] % (p - 1), p)
c2 = exp.fast(aux3, SK[1] % (q - 1), q)
ext = gcd.extended(p, q)
aux4 = (c1 * ext[4] * q + c2 * ext[3] * p) % SK[0]
output += STR.int2Text(aux4, size)
ctext = ctext[size + 2:]
print("Message:")
print(output)
def miller_rabin_test(base, n, s, d):
neg = n - 1
m = exp.fast(base, d, n)
# a^d kong. 1 (mod n) akkor prím, vagy
if m == 1:
return True
# r {0, 1, ..., s-1}
else:
r = 1
m = exp.fast(base, d, n)
if m == -1 or m == neg:
return True
while r < s:
m = exp.fast(m, 2, n)
if m == -1 or m == neg:
return True
r = r + 1
return False
def enc_string():
global PK
if not check_state():
return
ptext = str(input("Message: "))
size = STR.modSize(PK[0])
output = []
while ptext:
nbytes = min(len(ptext), size - 1)
aux1 = STR.text2Int(ptext[:nbytes])
assert aux1 < PK[0]
aux2 = exp.fast(aux1, PK[1], PK[0])
output += STR.int2List(aux2, size + 2)
ptext = ptext[size:]
s = str(base64.b64encode(bytearray(STR.get_hex_string(output), 'utf8')))[2:-1]
print("Encrypted message:")
print(s)