Exemple #1
0
def get_prr_masks(secret, word, prob_f, num_bits):

    #h = hmac.new(secret, word, digestmod=hashlib.sha256)
    h = HMAC_DRBG(os.urandom(64))
    #log('word %s, secret %s, HMAC-SHA256 %s', word, secret, h.hexdigest())

    # Now go through each byte
    digest_bytes = h.generate(num_bits)
    assert len(digest_bytes) == num_bits

    # Use 32 bits.  If we want 64 bits, it may be fine to generate another 32
    # bytes by repeated HMAC.  For arbitrary numbers of bytes it's probably
    # better to use the HMAC-DRBG algorithm.
    if num_bits > len(digest_bytes):
        raise RuntimeError('%d bits is more than the max of %d', num_bits,
                           len(digest_bytes))

    threshold128 = prob_f * 128

    uniform = 0
    f_mask = 0

    for i in xrange(num_bits):
        ch = digest_bytes[i]
        byte = ord(ch)

        u_bit = byte & 0x01  # 1 bit of entropy
        uniform |= (u_bit << i)  # maybe set bit in mask

        rand128 = byte >> 1  # 7 bits of entropy
        noise_bit = (rand128 < threshold128)
        f_mask |= (noise_bit << i)  # maybe set bit in mask

    return uniform, f_mask
Exemple #2
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def get_prr_masks(secret, word, prob_f, num_bits):
    h = hmac.new(secret.encode(), word, digestmod=hashlib.sha256)
    #print (word)
    rbg = HMAC_DRBG(entropy=os.urandom(64),
                    requested_security_strength=256,
                    personalization_string=word)

    #log('word %s, secret %s, HMAC-SHA256 %s', word, secret, h.hexdigest())
    #h = HMAC_DRBG (entropy=os.urandom(64),requested_security_strength=256, personalization_string=word)

    # Now go through each byte
    digest_bytes1 = h.digest()
    digest_bytes = rbg.generate(num_bits)
    #assert len(digest_bytes)==len(digest_bytes1)
    #assert len(digest_bytes) == 32

    # Use 32 bits.  If we want 64 bits, it may be fine to generate another 32
    # bytes by repeated HMAC.  For arbitrary numbers of bytes it's probably
    # better to use the HMAC-DRBG algorithm.
    #if num_bits > len(digest_bytes):
    # raise RuntimeError('%d bits is more than the max of %d', num_bits, len(d))

    threshold128 = prob_f * 128

    uniform = 0
    f_mask = 0

    for i in range(num_bits):
        ch = digest_bytes[i]
        byte = ch

        u_bit = byte & 0x01  # 1 bit of entropy
        uniform |= (u_bit << i)  # maybe set bit in mask

        rand128 = byte >> 1  # 7 bits of entropy
        noise_bit = (rand128 < threshold128)
        f_mask |= (noise_bit << i)  # maybe set bit in mask

    return uniform, f_mask
Exemple #3
0
import os
from hmac_drbg import HMAC_DRBG


drbg = HMAC_DRBG (entropy=os.urandom (64))

while True:
	secret = drbg.generate (1)

	if secret is None:
		drbg.reseed (entropy=os.urandom (32))
		secret = drbg.generate (1)

	secret = ord (secret) & 0xF

	print "Guess my lucky number (0 to 15):"
	guess = raw_input ('# ')

	if int (guess) == secret:
		print "You got it!"
	else:
		print "Nope, it was", secret
from __future__ import print_function

import os
from hmac_drbg import HMAC_DRBG

try:
    input = raw_input
except NameError:
    pass

drbg = HMAC_DRBG (entropy=os.urandom (64))

while True:
	secret = drbg.generate (1)

	if secret is None:
		drbg.reseed (entropy=os.urandom (32))
		secret = drbg.generate (1)

	secret = ord (secret) & 0xF

	print ("Guess my lucky number (0 to 15):")
	guess = input ('# ')

	if int (guess) == secret:
		print ("You got it!")
	else:
		print ("Nope, it was", secret)
Exemple #5
0
		# Read stimulus and expected result
		EntropyInput = read_entry (f, b'EntropyInput')
		Nonce = read_entry (f, b'Nonce')
		PersonalizationString = read_entry (f, b'PersonalizationString')
		EntropyInputReseed = read_entry (f, b'EntropyInputReseed')
		AdditionalInputReseed = read_entry (f, b'AdditionalInputReseed')
		AdditionalInput0 = read_entry (f, b'AdditionalInput')
		AdditionalInput1 = read_entry (f, b'AdditionalInput')
		ReturnedBits = read_entry (f, b'ReturnedBits')

		# This implementation does not support additional input
		if AdditionalInputReseed != b'' or AdditionalInput0 != b'' or AdditionalInput1 != b'':
			continue

		# Test
		drbg = HMAC_DRBG (entropy=(EntropyInput + Nonce), personalization_string=PersonalizationString)
		drbg.reseed (entropy=EntropyInputReseed)
		drbg.generate (len (ReturnedBits))
		result = drbg.generate (len (ReturnedBits))

		if result != ReturnedBits:
			print ("FAILURE")
			print ("EntropyInput = ", codecs.encode (EntropyInput, 'hex'))
			print ("Nonce = ", codecs.encode (Nonce, 'hex'))
			print ("PersonalizationString = ", codecs.encode (PersonalizationString, 'hex'))
			print ("EntropyInputReseed = ", codecs.encode (EntropyInputReseed, 'hex'))
			print ("AdditionalInputReseed = ", codecs.encode (AdditionalInputReseed, 'hex'))
			print ("AdditionalInput = ", codecs.encode (AdditionalInput0, 'hex'))
			print ("AdditionalInput = ", codecs.encode (AdditionalInput1, 'hex'))
			print ("ReturnedBits = ", codecs.encode (ReturnedBits, 'hex'))
			sys.exit (-1)
Exemple #6
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        # Read stimulus and expected result
        EntropyInput = read_entry(f, b'EntropyInput')
        Nonce = read_entry(f, b'Nonce')
        PersonalizationString = read_entry(f, b'PersonalizationString')
        EntropyInputReseed = read_entry(f, b'EntropyInputReseed')
        AdditionalInputReseed = read_entry(f, b'AdditionalInputReseed')
        AdditionalInput0 = read_entry(f, b'AdditionalInput')
        AdditionalInput1 = read_entry(f, b'AdditionalInput')
        ReturnedBits = read_entry(f, b'ReturnedBits')

        # This implementation does not support additional input
        if AdditionalInputReseed != b'' or AdditionalInput0 != b'' or AdditionalInput1 != b'':
            continue

        # Test
        drbg = HMAC_DRBG(entropy=(EntropyInput + Nonce),
                         personalization_string=PersonalizationString)
        drbg.reseed(entropy=EntropyInputReseed)
        drbg.generate(len(ReturnedBits))
        result = drbg.generate(len(ReturnedBits))

        if result != ReturnedBits:
            print("FAILURE")
            print("EntropyInput = ", codecs.encode(EntropyInput, 'hex'))
            print("Nonce = ", codecs.encode(Nonce, 'hex'))
            print("PersonalizationString = ",
                  codecs.encode(PersonalizationString, 'hex'))
            print("EntropyInputReseed = ",
                  codecs.encode(EntropyInputReseed, 'hex'))
            print("AdditionalInputReseed = ",
                  codecs.encode(AdditionalInputReseed, 'hex'))
            print("AdditionalInput = ", codecs.encode(AdditionalInput0, 'hex'))