diff options
Diffstat (limited to 'src/leap/soledad/client')
| -rw-r--r-- | src/leap/soledad/client/_crypto.py | 7 | ||||
| -rw-r--r-- | src/leap/soledad/client/_preamble.py | 88 |
2 files changed, 5 insertions, 90 deletions
diff --git a/src/leap/soledad/client/_crypto.py b/src/leap/soledad/client/_crypto.py index d0fb6e7f..998b70fa 100644 --- a/src/leap/soledad/client/_crypto.py +++ b/src/leap/soledad/client/_crypto.py @@ -86,8 +86,11 @@ from cryptography.hazmat.backends import default_backend from zope.interface import implementer -from ._preamble import InvalidPreambleException, decode_preamble, Preamble -from ._preamble import ENC_SCHEME, ENC_METHOD, BLOB_SIGNATURE_MAGIC +from leap.soledad.common.preamble import InvalidPreambleException +from leap.soledad.common.preamble import decode_preamble +from leap.soledad.common.preamble import Preamble +from leap.soledad.common.preamble import ENC_SCHEME, ENC_METHOD +from leap.soledad.common.preamble import BLOB_SIGNATURE_MAGIC SECRET_LENGTH = 64 diff --git a/src/leap/soledad/client/_preamble.py b/src/leap/soledad/client/_preamble.py deleted file mode 100644 index 262d70ce..00000000 --- a/src/leap/soledad/client/_preamble.py +++ /dev/null @@ -1,88 +0,0 @@ -# -*- coding: utf-8 -*- -# _preamble.py -# Copyright (C) 2017 LEAP Encryption Access Project -# -# This program is free software: you can redistribute it and/or modify -# it under the terms of the GNU General Public License as published by -# the Free Software Foundation, either version 3 of the License, or -# (at your option) any later version. -# -# This program is distributed in the hope that it will be useful, -# but WITHOUT ANY WARRANTY; without even the implied warranty of -# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -# GNU General Public License for more details. -# -# You should have received a copy of the GNU General Public License -# along with this program. If not, see <http://www.gnu.org/licenses/>. -""" -Preamble is a metadata payload present on encrypted documents. It holds data -about encryption scheme, iv, document id and sync related data. - BLOB_SIGNATURE_MAGIC, -> used to differentiate from other data formats - ENC_SCHEME, -> cryptographic scheme (symmetric or asymmetric) - ENC_METHOD, -> cipher used, such as AES-GCM or AES-CTR or GPG - current_time, -> time.time() - self.iv, -> initialization vector if any, or 0 when not applicable - str(self.doc_id), -> document id - str(self.rev), -> current revision - self._content_size) -> size, rounded to ceiling -""" -import warnings -import struct -import time -from collections import namedtuple -PACMAN = struct.Struct('2sbbQ16s255p255pQ') -LEGACY_PACMAN = struct.Struct('2sbbQ16s255p255p') # DEPRECATED -BLOB_SIGNATURE_MAGIC = '\x13\x37' -ENC_SCHEME = namedtuple('SCHEME', 'symkey')(1) -ENC_METHOD = namedtuple('METHOD', 'aes_256_ctr aes_256_gcm')(1, 2) - - -class InvalidPreambleException(Exception): - pass - - -class Preamble: - - def __init__(self, doc_id, rev, scheme, method, - timestamp=0, iv='', magic=None, content_size=0): - self.doc_id = doc_id - self.rev = rev - self.scheme = scheme - self.method = method - self.iv = iv - self.timestamp = int(timestamp) or int(time.time()) - self.magic = magic or BLOB_SIGNATURE_MAGIC - self.content_size = int(content_size) - - def encode(self): - preamble = PACMAN.pack( - self.magic, - self.scheme, - self.method, - self.timestamp, - self.iv, - str(self.doc_id), - str(self.rev), - self.content_size) - return preamble - - -def decode_preamble(encoded_preamble): - preamble_size = len(encoded_preamble) - try: - if preamble_size == LEGACY_PACMAN.size: - unpacked_data = LEGACY_PACMAN.unpack(encoded_preamble) - magic, sch, meth, ts, iv, doc_id, rev = unpacked_data - warnings.warn("Decoding a legacy preamble without size. " + - "This will be deprecated in 0.12. Doc was: " + - "doc_id: %s rev: %s" % (doc_id, rev), Warning) - return Preamble(doc_id, rev, sch, meth, ts, iv, magic) - elif preamble_size == PACMAN.size: - unpacked_data = PACMAN.unpack(encoded_preamble) - magic, sch, meth, ts, iv, doc_id, rev, size = unpacked_data - return Preamble(doc_id, rev, sch, meth, ts, iv, magic, int(size)) - else: - raise InvalidPreambleException("Unexpected preamble size %d", - preamble_size) - except struct.error as e: - raise InvalidPreambleException(e) |