def print_valid_time(prefix: str, cert: X509) -> None:
"""Print validity time of the certificate"""
validfrom_time = cert.get_notBefore()
validfrom_datetime = datetime.strptime(validfrom_time.decode("utf-8"),
"%Y%m%d%H%M%SZ")
validto_time = cert.get_notAfter()
validto_datetime = datetime.strptime(validto_time.decode("utf-8"),
"%Y%m%d%H%M%SZ")
print(f"{prefix}valid from: {validfrom_datetime}")
print(f"{prefix}valid to : {validto_datetime}")
def is_self_signed(cert: X509) -> bool:
"""
Checks if a X509 certificate is self signed.
"""
store = X509Store()
store.add_cert(cert)
validfrom_time = cert.get_notBefore()
validfrom_datetime = datetime.strptime(validfrom_time.decode("utf-8"),
"%Y%m%d%H%M%SZ")
store.set_time(validfrom_datetime)
store_ctx = X509StoreContext(store, cert)
try:
store_ctx.verify_certificate()
return True
except X509StoreContextError:
return False
