diff options
Diffstat (limited to 'python/olm/account.py')
| -rw-r--r-- | python/olm/account.py | 62 |
1 files changed, 42 insertions, 20 deletions
diff --git a/python/olm/account.py b/python/olm/account.py index 1dba96d..8455655 100644 --- a/python/olm/account.py +++ b/python/olm/account.py @@ -37,7 +37,7 @@ from future.utils import bytes_to_native_str # pylint: disable=no-name-in-module from _libolm import ffi, lib # type: ignore -from ._compat import URANDOM, to_bytes +from ._compat import URANDOM, to_bytearray from ._finalize import track_for_finalization # This is imported only for type checking purposes @@ -82,12 +82,12 @@ class Account(object): random_length = lib.olm_create_account_random_length(self._account) random = URANDOM(random_length) - random_buffer = ffi.new("char[]", random) self._check_error( - lib.olm_create_account(self._account, random_buffer, + lib.olm_create_account(self._account, ffi.from_buffer(random), random_length)) + def _check_error(self, ret): # type: (int) -> None if ret != lib.olm_error(): @@ -111,15 +111,23 @@ class Account(object): passphrase(str, optional): The passphrase to be used to encrypt the account. """ - byte_key = bytes(passphrase, "utf-8") if passphrase else b"" - key_buffer = ffi.new("char[]", byte_key) + byte_key = bytearray(passphrase, "utf-8") if passphrase else b"" pickle_length = lib.olm_pickle_account_length(self._account) pickle_buffer = ffi.new("char[]", pickle_length) - self._check_error( - lib.olm_pickle_account(self._account, key_buffer, len(byte_key), - pickle_buffer, pickle_length)) + try: + self._check_error( + lib.olm_pickle_account(self._account, + ffi.from_buffer(byte_key), + len(byte_key), + pickle_buffer, + pickle_length)) + finally: + # zero out copies of the passphrase + for i in range(0, len(byte_key)): + byte_key[i] = 0 + return ffi.unpack(pickle_buffer, pickle_length) @classmethod @@ -143,15 +151,22 @@ class Account(object): if not pickle: raise ValueError("Pickle can't be empty") - byte_key = bytes(passphrase, "utf-8") if passphrase else b"" - key_buffer = ffi.new("char[]", byte_key) + byte_key = bytearray(passphrase, "utf-8") if passphrase else b"" + # copy because unpickle will destroy the buffer pickle_buffer = ffi.new("char[]", pickle) obj = cls.__new__(cls) - ret = lib.olm_unpickle_account(obj._account, key_buffer, len(byte_key), - pickle_buffer, len(pickle)) - obj._check_error(ret) + try: + ret = lib.olm_unpickle_account(obj._account, + ffi.from_buffer(byte_key), + len(byte_key), + pickle_buffer, + len(pickle)) + obj._check_error(ret) + finally: + for i in range(0, len(byte_key)): + byte_key[i] = 0 return obj @@ -178,14 +193,21 @@ class Account(object): Args: message(str): The message to sign. """ - bytes_message = to_bytes(message) + bytes_message = to_bytearray(message) out_length = lib.olm_account_signature_length(self._account) - message_buffer = ffi.new("char[]", bytes_message) out_buffer = ffi.new("char[]", out_length) - self._check_error( - lib.olm_account_sign(self._account, message_buffer, - len(bytes_message), out_buffer, out_length)) + try: + self._check_error( + lib.olm_account_sign(self._account, + ffi.from_buffer(bytes_message), + len(bytes_message), out_buffer, + out_length)) + finally: + # clear out copies of the message, which may be plaintext + if bytes_message is not message: + for i in range(0, len(bytes_message)): + bytes_message[i] = 0 return bytes_to_native_str(ffi.unpack(out_buffer, out_length)) @@ -214,10 +236,10 @@ class Account(object): random_length = lib.olm_account_generate_one_time_keys_random_length( self._account, count) random = URANDOM(random_length) - random_buffer = ffi.new("char[]", random) + self._check_error( lib.olm_account_generate_one_time_keys( - self._account, count, random_buffer, random_length)) + self._account, count, ffi.from_buffer(random), random_length)) @property def one_time_keys(self): |