From 846ab858a6dd2e962d3e110147f4274416026f5a Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Thu, 19 May 2016 12:01:15 +0100 Subject: [PATCH] Python wrapper: support for inbound group sessions --- python/olm/__init__.py | 1 + python/olm/__main__.py | 76 +++++++++++++++++++++++-- python/olm/inbound_group_session.py | 86 +++++++++++++++++++++++++++++ python/test_olm.sh | 6 +- 4 files changed, 162 insertions(+), 7 deletions(-) create mode 100644 python/olm/inbound_group_session.py diff --git a/python/olm/__init__.py b/python/olm/__init__.py index 8681d12..31b29b9 100644 --- a/python/olm/__init__.py +++ b/python/olm/__init__.py @@ -1,3 +1,4 @@ from .account import Account from .session import Session from .outbound_group_session import OutboundGroupSession +from .inbound_group_session import InboundGroupSession diff --git a/python/olm/__main__.py b/python/olm/__main__.py index 8bb2419..3fcf24d 100755 --- a/python/olm/__main__.py +++ b/python/olm/__main__.py @@ -210,14 +210,43 @@ def build_arg_parser(): outbound_group.add_argument("session_file", help="Local group session file") outbound_group.set_defaults(func=do_outbound_group) + group_credentials = commands.add_parser("group_credentials", help="Export the current outbound group session credentials") + group_credentials.add_argument("session_file", help="Local outbound group session file") + group_credentials.add_argument("credentials_file", help="File to write credentials to (default stdout)", + type=argparse.FileType('w'), nargs='?', + default=sys.stdout) + group_credentials.set_defaults(func=do_group_credentials) + group_encrypt = commands.add_parser("group_encrypt", help="Encrypt a group message") - group_encrypt.add_argument("session_file", help="Local group session file") - group_encrypt.add_argument("plaintext_file", help="Plaintext", - type=argparse.FileType('rb'), default=sys.stdin) - group_encrypt.add_argument("message_file", help="Message", - type=argparse.FileType('wb'), default=sys.stdout) + group_encrypt.add_argument("session_file", help="Local outbound group session file") + group_encrypt.add_argument("plaintext_file", help="Plaintext file (default stdin)", + type=argparse.FileType('rb'), nargs='?', + default=sys.stdin) + group_encrypt.add_argument("message_file", help="Message file (default stdout)", + type=argparse.FileType('w'), nargs='?', + default=sys.stdout) group_encrypt.set_defaults(func=do_group_encrypt) + inbound_group = commands.add_parser( + "inbound_group", + help=("Create an inbound group session based on credentials from an "+ + "outbound group session")) + inbound_group.add_argument("session_file", help="Local inbound group session file") + inbound_group.add_argument("credentials_file", + help="File to read credentials from (default stdin)", + type=argparse.FileType('r'), nargs='?', + default=sys.stdin) + inbound_group.set_defaults(func=do_inbound_group) + + group_decrypt = commands.add_parser("group_decrypt", help="Decrypt a group message") + group_decrypt.add_argument("session_file", help="Local inbound group session file") + group_decrypt.add_argument("message_file", help="Message file (default stdin)", + type=argparse.FileType('r'), nargs='?', + default=sys.stdin) + group_decrypt.add_argument("plaintext_file", help="Plaintext file (default stdout)", + type=argparse.FileType('wb'), nargs='?', + default=sys.stdout) + group_decrypt.set_defaults(func=do_group_decrypt) return parser def do_outbound_group(args): @@ -240,6 +269,43 @@ def do_group_encrypt(args): f.write(session.pickle(args.key)) args.message_file.write(message) +def do_group_credentials(args): + session = OutboundGroupSession() + with open(args.session_file, "rb") as f: + session.unpickle(args.key, f.read()) + result = { + 'message_index': session.message_index(), + 'session_key': session.session_key(), + } + json.dump(result, args.credentials_file, indent=4) + +def do_inbound_group(args): + if os.path.exists(args.session_file): + sys.stderr.write("Session %r file already exists\n" % ( + args.session_file, + )) + sys.exit(1) + credentials = json.load(args.credentials_file) + for k in ('message_index', 'session_key'): + if not k in credentials: + sys.stderr.write("Credentials file is missing %s\n" % k) + sys.exit(1); + + session = InboundGroupSession() + session.init(credentials['message_index'], credentials['session_key']) + with open(args.session_file, "wb") as f: + f.write(session.pickle(args.key)) + +def do_group_decrypt(args): + session = InboundGroupSession() + with open(args.session_file, "rb") as f: + session.unpickle(args.key, f.read()) + message = args.message_file.read() + plaintext = session.decrypt(message) + with open(args.session_file, "wb") as f: + f.write(session.pickle(args.key)) + args.plaintext_file.write(plaintext) + if __name__ == '__main__': parser = build_arg_parser() args = parser.parse_args() diff --git a/python/olm/inbound_group_session.py b/python/olm/inbound_group_session.py new file mode 100644 index 0000000..6c01095 --- /dev/null +++ b/python/olm/inbound_group_session.py @@ -0,0 +1,86 @@ +import json + +from ._base import * + +lib.olm_inbound_group_session_size.argtypes = [] +lib.olm_inbound_group_session_size.restype = c_size_t + +lib.olm_inbound_group_session.argtypes = [c_void_p] +lib.olm_inbound_group_session.restype = c_void_p + +lib.olm_inbound_group_session_last_error.argtypes = [c_void_p] +lib.olm_inbound_group_session_last_error.restype = c_char_p + +def inbound_group_session_errcheck(res, func, args): + if res == ERR: + raise OlmError("%s: %s" % ( + func.__name__, lib.olm_inbound_group_session_last_error(args[0]) + )) + return res + + +def inbound_group_session_function(func, *types): + func.argtypes = (c_void_p,) + types + func.restypes = c_size_t + func.errcheck = inbound_group_session_errcheck + + +inbound_group_session_function( + lib.olm_pickle_inbound_group_session, c_void_p, c_size_t, c_void_p, c_size_t +) +inbound_group_session_function( + lib.olm_unpickle_inbound_group_session, c_void_p, c_size_t, c_void_p, c_size_t +) + +inbound_group_session_function( + lib.olm_init_inbound_group_session, c_uint32, c_void_p, c_size_t +) + +inbound_group_session_function( + lib.olm_group_decrypt_max_plaintext_length, c_void_p, c_size_t +) +inbound_group_session_function( + lib.olm_group_decrypt, + c_void_p, c_size_t, # message + c_void_p, c_size_t, # plaintext +) + +class InboundGroupSession(object): + def __init__(self): + self.buf = create_string_buffer(lib.olm_inbound_group_session_size()) + self.ptr = lib.olm_inbound_group_session(self.buf) + + def pickle(self, key): + key_buffer = create_string_buffer(key) + pickle_length = lib.olm_pickle_inbound_group_session_length(self.ptr) + pickle_buffer = create_string_buffer(pickle_length) + lib.olm_pickle_inbound_group_session( + self.ptr, key_buffer, len(key), pickle_buffer, pickle_length + ) + return pickle_buffer.raw + + def unpickle(self, key, pickle): + key_buffer = create_string_buffer(key) + pickle_buffer = create_string_buffer(pickle) + lib.olm_unpickle_inbound_group_session( + self.ptr, key_buffer, len(key), pickle_buffer, len(pickle) + ) + + def init(self, message_index, session_key): + key_buffer = create_string_buffer(session_key) + lib.olm_init_inbound_group_session( + self.ptr, message_index, key_buffer, len(session_key) + ) + + def decrypt(self, message): + message_buffer = create_string_buffer(message) + max_plaintext_length = lib.olm_group_decrypt_max_plaintext_length( + self.ptr, message_buffer, len(message) + ) + plaintext_buffer = create_string_buffer(max_plaintext_length) + message_buffer = create_string_buffer(message) + plaintext_length = lib.olm_group_decrypt( + self.ptr, message_buffer, len(message), + plaintext_buffer, max_plaintext_length + ) + return plaintext_buffer.raw[:plaintext_length] diff --git a/python/test_olm.sh b/python/test_olm.sh index 0ea1623..da69581 100755 --- a/python/test_olm.sh +++ b/python/test_olm.sh @@ -7,10 +7,11 @@ ALICE_SESSION=alice.session ALICE_GROUP_SESSION=alice.group_session BOB_ACCOUNT=bob.account BOB_SESSION=bob.session +BOB_GROUP_SESSION=bob.group_session rm $ALICE_ACCOUNT $BOB_ACCOUNT rm $ALICE_SESSION $BOB_SESSION -rm $ALICE_GROUP_SESSION +rm $ALICE_GROUP_SESSION $BOB_GROUP_SESSION $OLM create_account $ALICE_ACCOUNT $OLM create_account $BOB_ACCOUNT @@ -27,4 +28,5 @@ echo "Hello world" | $OLM encrypt $ALICE_SESSION - - | $OLM inbound $BOB_ACCOUNT ### group sessions $OLM outbound_group $ALICE_GROUP_SESSION -echo "Hello world" | $OLM group_encrypt $ALICE_GROUP_SESSION - - +$OLM group_credentials $ALICE_GROUP_SESSION | $OLM inbound_group $BOB_GROUP_SESSION +echo "Hello group" | $OLM group_encrypt $ALICE_GROUP_SESSION - - | $OLM group_decrypt $BOB_GROUP_SESSION