Python Integer.random方法代码示例

# 需要导入模块: from Cryptodome.Math.Numbers import Integer [as 别名]
# 或者: from Cryptodome.Math.Numbers.Integer import random [as 别名]
    def test_random_exact_bits(self):

        for _ in xrange(1000):
            a = IntegerGeneric.random(exact_bits=8)
            self.failIf(a < 128)
            self.failIf(a >= 256)

        for bits_value in xrange(1024, 1024 + 8):
            a = IntegerGeneric.random(exact_bits=bits_value)
            self.failIf(a < 2**(bits_value - 1))
            self.failIf(a >= 2**bits_value)

# 需要导入模块: from Cryptodome.Math.Numbers import Integer [as 别名]
# 或者: from Cryptodome.Math.Numbers.Integer import random [as 别名]
    def test_random_max_bits(self):

        flag = False
        for _ in xrange(1000):
            a = IntegerGeneric.random(max_bits=8)
            flag = flag or a < 128
            self.failIf(a>=256)
        self.failUnless(flag)

        for bits_value in xrange(1024, 1024 + 8):
            a = IntegerGeneric.random(max_bits=bits_value)
            self.failIf(a >= 2**bits_value)

# 需要导入模块: from Cryptodome.Math.Numbers import Integer [as 别名]
# 或者: from Cryptodome.Math.Numbers.Integer import random [as 别名]
    def __mul__(self, scalar):
        """Return a new point, the scalar product of this one"""

        if scalar < 0:
            raise ValueError("Scalar multiplication only defined for non-negative integers")

        # Trivial results
        if scalar == 0 or self.is_point_at_infinity():
            return self.point_at_infinity()
        elif scalar == 1:
            return self.copy()

        # Scalar randomization
        scalar_blind = Integer.random(exact_bits=64) * _curve.order + scalar

        # Montgomery key ladder
        r = [self.point_at_infinity().copy(), self.copy()]
        bit_size = int(scalar_blind.size_in_bits())
        scalar_int = int(scalar_blind)
        for i in range(bit_size, -1, -1):
            di = scalar_int >> i & 1
            r[di ^ 1] += r[di]
            r[di].double()

        return r[0]

# 需要导入模块: from Cryptodome.Math.Numbers import Integer [as 别名]
# 或者: from Cryptodome.Math.Numbers.Integer import random [as 别名]
def generate_probable_prime(**kwargs):
    """Generate a random probable prime.

    The prime will not have any specific properties
    (e.g. it will not be a *strong* prime).

    Random numbers are evaluated for primality until one
    passes all tests, consisting of a certain number of
    Miller-Rabin tests with random bases followed by
    a single Lucas test.

    The number of Miller-Rabin iterations is chosen such that
    the probability that the output number is a non-prime is
    less than 1E-30 (roughly 2^{-100}).

    This approach is compliant to `FIPS PUB 186-4`__.

    :Keywords:
      exact_bits : integer
        The desired size in bits of the probable prime.
        It must be at least 160.
      randfunc : callable
        An RNG function where candidate primes are taken from.
      prime_filter : callable
        A function that takes an Integer as parameter and returns
        True if the number can be passed to further primality tests,
        False if it should be immediately discarded.

    :Return:
        A probable prime in the range 2^exact_bits > p > 2^(exact_bits-1).

    .. __: http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf
    """

    exact_bits = kwargs.pop("exact_bits", None)
    randfunc = kwargs.pop("randfunc", None)
    prime_filter = kwargs.pop("prime_filter", lambda x: True)
    if kwargs:
        print "Unknown parameters:", kwargs.keys()

    if exact_bits is None:
        raise ValueError("Missing exact_bits parameter")
    if exact_bits < 160:
        raise ValueError("Prime number is not big enough.")

    if randfunc is None:
        randfunc = Random.new().read

    result = COMPOSITE
    while result == COMPOSITE:
        candidate = Integer.random(exact_bits=exact_bits,
                                   randfunc=randfunc) | 1
        if not prime_filter(candidate):
            continue
        result = test_probable_prime(candidate, randfunc)
    return candidate

# 需要导入模块: from Cryptodome.Math.Numbers import Integer [as 别名]
# 或者: from Cryptodome.Math.Numbers.Integer import random [as 别名]
    def _get_weak_domain(self):

        from Cryptodome.Math.Numbers import Integer
        from Cryptodome.Math import Primality

        p = Integer(4)
        while p.size_in_bits() != 1024 or Primality.test_probable_prime(p) != Primality.PROBABLY_PRIME:
            q1 = Integer.random(exact_bits=80)
            q2 = Integer.random(exact_bits=80)
            q = q1 * q2
            z = Integer.random(exact_bits=1024-160)
            p = z * q + 1

        h = Integer(2)
        g = 1
        while g == 1:
            g = pow(h, z, p)
            h += 1

        return (p, q, g)

# 需要导入模块: from Cryptodome.Math.Numbers import Integer [as 别名]
# 或者: from Cryptodome.Math.Numbers.Integer import random [as 别名]
    def test_random_bits_custom_rng(self):

        class CustomRNG(object):
            def __init__(self):
                self.counter = 0

            def __call__(self, size):
                self.counter += size
                return bchr(0) * size

        custom_rng = CustomRNG()
        a = IntegerGeneric.random(exact_bits=32, randfunc=custom_rng)
        self.assertEqual(custom_rng.counter, 4)

# 需要导入模块: from Cryptodome.Math.Numbers import Integer [as 别名]
# 或者: from Cryptodome.Math.Numbers.Integer import random [as 别名]
def generate(bits, randfunc=None, domain=None):
    """Generate a new DSA key pair.

    The algorithm follows Appendix A.1/A.2 and B.1 of `FIPS 186-4`_,
    respectively for domain generation and key pair generation.

    Args:
      bits (integer):
        Key length, or size (in bits) of the DSA modulus *p*.
        It must be 1024, 2048 or 3072.

      randfunc (callable):
        Random number generation function; it accepts a single integer N
        and return a string of random data N bytes long.
        If not specified, :func:`Cryptodome.Random.get_random_bytes` is used.

      domain (tuple):
        The DSA domain parameters *p*, *q* and *g* as a list of 3
        integers. Size of *p* and *q* must comply to `FIPS 186-4`_.
        If not specified, the parameters are created anew.

    Returns:
      :class:`DsaKey` : a new DSA key object

    Raises:
      ValueError : when **bits** is too little, too big, or not a multiple of 64.

    .. _FIPS 186-4: http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf
    """

    if randfunc is None:
        randfunc = Random.get_random_bytes

    if domain:
        p, q, g = map(Integer, domain)

        ## Perform consistency check on domain parameters
        # P and Q must be prime
        fmt_error = test_probable_prime(p) == COMPOSITE
        fmt_error = test_probable_prime(q) == COMPOSITE
        # Verify Lagrange's theorem for sub-group
        fmt_error |= ((p - 1) % q) != 0
        fmt_error |= g <= 1 or g >= p
        fmt_error |= pow(g, q, p) != 1
        if fmt_error:
            raise ValueError("Invalid DSA domain parameters")
    else:
        p, q, g, _ = _generate_domain(bits, randfunc)

    L = p.size_in_bits()
    N = q.size_in_bits()

    if L != bits:
        raise ValueError("Mismatch between size of modulus (%d)"
                         " and 'bits' parameter (%d)" % (L, bits))

    if (L, N) not in [(1024, 160), (2048, 224),
                      (2048, 256), (3072, 256)]:
        raise ValueError("Lengths of p and q (%d, %d) are not compatible"
                         "to FIPS 186-3" % (L, N))

    if not 1 < g < p:
        raise ValueError("Incorrent DSA generator")

    # B.1.1
    c = Integer.random(exact_bits=N + 64)
    x = c % (q - 1) + 1 # 1 <= x <= q-1
    y = pow(g, x, p)

    key_dict = { 'y':y, 'g':g, 'p':p, 'q':q, 'x':x }
    return DsaKey(key_dict)