diff options
Diffstat (limited to 'client/src/leap/soledad/client/_crypto.py')
| -rw-r--r-- | client/src/leap/soledad/client/_crypto.py | 58 |
1 files changed, 7 insertions, 51 deletions
diff --git a/client/src/leap/soledad/client/_crypto.py b/client/src/leap/soledad/client/_crypto.py index c152502d..8dbdc094 100644 --- a/client/src/leap/soledad/client/_crypto.py +++ b/client/src/leap/soledad/client/_crypto.py @@ -307,48 +307,6 @@ class BlobEncryptor(object): return defer.succeed(result) -class CryptoStreamBodyProducer(FileBodyProducer): - - """ - A BodyProducer that gets the tag from the last 16 bytes before closing the - fd. - """ - _tag = None - - @property - def tag(self): - # XXX this is a bit tricky. If you call this - # before the end of the stream, you will ruin everything - if not self._tag: - self._writeTag() - return self._tag - - def _writeTag(self): - fd = self._inputFile - fd.seek(-16, os.SEEK_END) - self._tag = fd.read(16) - fd.seek(0) - - def stopProducing(self): - self._writeTag() - self._inputFile.close() - self._task.stop() - - def _writeloop(self, consumer): - """ - Return an iterator which reads one chunk of bytes from the input file - and writes them to the consumer for each time it is iterated. - """ - while True: - bytes = self._inputFile.read(self._readSize) - if not bytes: - self._writeTag() - self._inputFile.close() - break - consumer.write(base64.urlsafe_b64decode(bytes)) - yield None - - # TODO maybe rename this to just Decryptor, since it will be used by blobs # and non blobs in soledad. class BlobDecryptor(object): @@ -381,14 +339,13 @@ class BlobDecryptor(object): self.result = result or BytesIO() sym_key = _get_sym_key_for_doc(doc_info.doc_id, secret) - self._aes = AESWriter(sym_key, iv, self.result, tag=None) + self._aes = AESWriter(sym_key, iv, self.result, tag=self.tag) self._aes.authenticate(preamble) if start_stream: self._start_stream() def _start_stream(self): - self._producer = CryptoStreamBodyProducer(self.fd, readSize=2**16) - self._producer.armor = self.armor + self._producer = FileBodyProducer(self.fd, readSize=2**16) def _consume_preamble(self): @@ -397,6 +354,8 @@ class BlobDecryptor(object): parts = self.fd.getvalue().split() encoded_preamble = parts[0] preamble = base64.urlsafe_b64decode(encoded_preamble) + ciphertext = base64.urlsafe_b64decode(parts[1]) + self.tag, ciphertext = ciphertext[-16:], ciphertext[:-16] except (TypeError, ValueError): raise InvalidBlob @@ -433,21 +392,18 @@ class BlobDecryptor(object): raise InvalidBlob('invalid doc id') self.fd.seek(0) - tail = ''.join(parts[1:]) - self.fd.write(tail) - self.fd.seek(len(tail)) + self.fd.write(ciphertext) + self.fd.seek(len(ciphertext)) self.fd.truncate() self.fd.seek(0) return preamble, iv def _end_stream(self): try: - self._aes.end()[1] + self._aes.end() except InvalidTag: raise InvalidBlob('Invalid Tag. Blob authentication failed.') fd = self.result - fd.seek(-16, os.SEEK_END) - fd.truncate() fd.seek(0) return self.result |