def random_passphrase_from_wordlist(phrase_length, wordlist):
""" An extremely entropy efficient passphrase generator.
This function:
-Pulls entropy from the safer alternative to /dev/urandom: /dev/random
-Doesn't rely on random.seed (words are selected right from the entropy)
-Only requires 2 entropy bytes/word for word lists of up to 65536 words
"""
passphrase_words = []
numbytes_of_entropy = phrase_length * 2
entropy = list(
dev_random_entropy(numbytes_of_entropy, fallback_to_urandom=True))
bytes_per_word = int(ceil(log(len(wordlist), 2) / 8))
if (phrase_length * bytes_per_word > 64):
raise Exception("Error! This operation requires too much entropy. \
Try a shorter phrase length or word list.")
for i in range(phrase_length):
current_entropy = entropy[i * bytes_per_word:(i + 1) * bytes_per_word]
index = int(''.join(current_entropy).encode('hex'), 16) % len(wordlist)
word = wordlist[index]
passphrase_words.append(word)
return " ".join(passphrase_words)
def random_passphrase_from_wordlist(phrase_length, wordlist):
""" An extremely entropy efficient passphrase generator.
This function:
-Pulls entropy from the safer alternative to /dev/urandom: /dev/random
-Doesn't rely on random.seed (words are selected right from the entropy)
-Only requires 2 entropy bytes/word for word lists of up to 65536 words
"""
passphrase_words = []
numbytes_of_entropy = phrase_length * 2
entropy = list(dev_random_entropy(numbytes_of_entropy, fallback_to_urandom=True))
bytes_per_word = int(ceil(log(len(wordlist), 2) / 8))
if (phrase_length * bytes_per_word > 64):
raise Exception("Error! This operation requires too much entropy. \
Try a shorter phrase length or word list.")
for i in range(phrase_length):
current_entropy = entropy[i*bytes_per_word:(i+1)*bytes_per_word]
index = int(''.join(current_entropy).encode('hex'), 16) % len(wordlist)
word = wordlist[index]
passphrase_words.append(word)
return " ".join(passphrase_words)
def random_secret_exponent(curve_order):
""" Generates a random secret exponent. """
# run a rejection sampling algorithm to ensure the random int is less
# than the curve order
while True:
# generate a random 256 bit hex string
random_hex = hexlify(dev_random_entropy(32))
random_int = int(random_hex, 16)
if random_int >= 1 and random_int < curve_order:
break
return random_int
def random_secret_exponent(curve_order):
""" Generates a random secret exponent. """
# run a rejection sampling algorithm to ensure the random int is less
# than the curve order
while True:
# generate a random 256 bit hex string
random_hex = hexlify(dev_random_entropy(32))
random_int = int(random_hex, 16)
if random_int >= 1 and random_int < curve_order:
break
return random_int
def random_secret_exponent(curve_order) -> int:
"""
This will be our "random" number generator using dev_random_entropy.
Generates a random hex number by calling the dev_random_entropy function, and then converts that byte data type into hexidecimal.
Generates a random int between the random entropy hexadecimal and 16.
If int is between the curve_order and 1 then it will return that int, which will be used as the secret exponent in the private key generation.
"""
while True:
random_hex = hexlify(dev_random_entropy(32))
random_int = int(random_hex, 16)
if random_int >= 1 and random_int < curve_order:
return random_int
def test_dev_random_entropy_fallback_on_nt_operating_system(self):
os.name = 'nt'
bytes16 = dev_random_entropy(16)
self.assertEqual(len(bytes16), 16)
def test_dev_random_entropy(self):
bytes16 = dev_random_entropy(16)
self.assertEqual(len(bytes16), 16)
def random_secret_exponent(curve_order):
while True:
random_hex = hexlify(dev_random_entropy(32))
random_int = int(random_hex, 16)
if random_int >= 1 and random_int < curve_order:
return random_int
def gen_31bit_num():
first_7_bits = int_to_hex(hex_to_int(hexlify(dev_random_entropy(1))) % 128)
last_24_bits = hexlify(dev_random_entropy(3))
return hex_to_int(first_7_bits + last_24_bits)
def gen_8bit_num():
return hex_to_int(hexlify(dev_random_entropy(1)))
def random_exponent(curve):
while 1:
random_hex = hexlify(dev_random_entropy(32))
random_int = int(random_hex, 16)
if 1 <= random_int < curve:
return random_int
