def validate(self):
if len(self.request.address) == 111:
return self.validate_extended(checksum_algo='blake256')
try:
decoded_address = base58check.b58decode(self.request.address)
except ValueError:
return False
# decoded address has to be 26 bytes long
if len(decoded_address) != 26:
return False
# original one has to start with D,T,S or R
if not self.request.address.startswith((b'D', b'T', b'S', b'R')):
return False
expected_checksum = decoded_address[-4:]
version_bytes = int.from_bytes(decoded_address[:2], byteorder='big')
if self.network == '':
return False
checksum = blake256.blake_hash(
blake256.blake_hash(decoded_address[:-4]))[:4]
# double blake256 checksum needs to be equal with the expected checksum
if checksum != expected_checksum:
return False
return True
def checksum(input):
"""
A checksum
Returns:
bytes: A 4-byte checksum.
"""
return blake_hash(blake_hash(input))[:4]
def checksum(b):
"""
A checksum.
Args:
b (byte-like): Bytes to obtain a checksum for.
Returns:
bytes: A 4-byte checksum.
"""
return blake_hash(blake_hash(b))[:4]
def validate_extended(self, checksum_algo='sha256'):
if len(self.request.address) != 111:
return False
if self.network == '':
return False
# strip leading "zeros" (the "1" digit with base58)
base58_stripped = self.request.address.decode('utf-8').lstrip("1")
# convert base58 to decimal
int_rep = 0
for base58_digit in base58_stripped:
int_rep *= 58
try:
int_rep += self.base58_digit_to_dec[base58_digit]
except KeyError:
# not a valid base58 digit -> invalid address
return False
# encode it to base64
hex_rep = "{:X}".format(int_rep)
# if the length is odd, add leading zero (needed for b16decode)
if len(hex_rep) % 2 == 1:
hex_rep = "0" + hex_rep
# decode it into a binary string, padded with zeros
# 72 bytes (extended key size) + 4 bytes (prefix version bytes)
all_bytes = base64.b16decode(hex_rep).rjust(82, b"\0")
# count leading zeros
zero_count = next(zeros for zeros, byte in enumerate(all_bytes)
if byte != 0)
# compare it with the number of leading zeros lstripped at the beginning
if len(self.request.address.decode('utf-8')) - len(
base58_stripped) != zero_count:
return False
if checksum_algo == 'blake256':
checksum = blake256.blake_hash(blake256.blake_hash(
all_bytes[:-4]))[:4]
elif checksum_algo == 'sha256':
checksum = sha256(sha256(all_bytes[:-4]).digest()).digest()[:4]
else:
return False
# checking if the checksum is valid
if checksum != all_bytes[-4:]:
return False
return True
def main():
h = ByteArray(
"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"
)
print(h)
print(blake_hash(h.bytes()).hex())
print(crypto.hash160(h.bytes()).hex())
def hashH(b):
"""
The BLAKE256 hash as a ByteArray.
Returns:
ByteArray: The hash.
"""
return ByteArray(blake_hash(b), length=BLAKE256_SIZE)
def hash160(b):
"""
A RIPEMD160 hash of the blake256 hash of the input.
Returns:
ByteArray: A 20-byte hash.
"""
h = hashlib.new("ripemd160")
h.update(blake_hash(b))
return ByteArray(h.digest())
def hashH(b):
"""
The BLAKE256 hash as a ByteArray.
Args:
b (byte-like): The thing to hash.
Returns:
ByteArray: The hash.
"""
return ByteArray(blake_hash(b), length=BLAKE256_SIZE)
def hash(self):
"""
Hash returns the BLAKE256 hash of the filter.
Returns:
ByteArray: The hash.
"""
# Empty filters have a hash of all zeroes.
nData = self.filterNData()
if len(nData) == 0:
return ByteArray(length=32)
return ByteArray(blake_hash(nData.bytes()))
def blake256d(data):
from blake256.blake256 import blake_hash
return blake_hash(blake_hash(data))
def H(m):
return blake_hash(m)
def create_commitment(pub): # Commitment is defined as the first 16 bytes of the hash of COMMIT + pubkey return blake_hash(b"COMMIT" + pub)[0:16]