Files
darkfi/script/research/streamlet/utils.py
2022-01-30 22:59:11 +02:00

55 lines
1.7 KiB
Python

from cryptography.hazmat.primitives import serialization, hashes
from cryptography.hazmat.primitives.asymmetric import rsa, padding
from cryptography.hazmat.backends import default_backend
from cryptography.exceptions import InvalidSignature
def generate_keys(private_key_password):
''' Generating the keys pair. Cryptographic algorithm used is for demostranation porpuses only. '''
private_key = rsa.generate_private_key(
public_exponent=65537,
key_size=2048
)
encrypted_pem_private_key = private_key.private_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PrivateFormat.PKCS8,
encryption_algorithm=serialization.BestAvailableEncryption(
private_key_password.encode()))
pem_public_key = private_key.public_key().public_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PublicFormat.SubjectPublicKeyInfo
)
return encrypted_pem_private_key, pem_public_key
def sign_message(password, private_key, message):
''' Signs a message using private_key. '''
privkey = serialization.load_pem_private_key(
private_key, password=password.encode(), backend=default_backend())
signed_message = privkey.sign(
message.encode(),
padding.PSS(
mgf=padding.MGF1(hashes.SHA256()),
salt_length=padding.PSS.MAX_LENGTH),
hashes.SHA256()
)
return signed_message
def verify_signature(public_key, message, signed_message):
''' Verifies a message against a public key. '''
pubkey = serialization.load_pem_public_key(
public_key, backend=default_backend())
try:
pubkey.verify(
signed_message,
message.encode(),
padding.PSS(
mgf=padding.MGF1(hashes.SHA256()),
salt_length=padding.PSS.MAX_LENGTH),
hashes.SHA256())
return True
except InvalidSignature:
return False