Merge pull request #42 from matrix-org/rav/megolm_export
Export and import of megolm session data
This commit is contained in:
commit
860740a91e
8 changed files with 426 additions and 38 deletions
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@ -85,7 +85,8 @@ size_t olm_unpickle_inbound_group_session(
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/**
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* Start a new inbound group session, based on the parameters supplied.
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* Start a new inbound group session, from a key exported from
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* olm_outbound_group_session_key
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*
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* Returns olm_error() on failure. On failure last_error will be set with an
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* error code. The last_error will be:
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@ -99,6 +100,23 @@ size_t olm_init_inbound_group_session(
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uint8_t const * session_key, size_t session_key_length
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);
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/**
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* Import an inbound group session, from a previous export.
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*
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* Returns olm_error() on failure. On failure last_error will be set with an
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* error code. The last_error will be:
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*
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* * OLM_INVALID_BASE64 if the session_key is not valid base64
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* * OLM_BAD_SESSION_KEY if the session_key is invalid
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*/
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size_t olm_import_inbound_group_session(
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OlmInboundGroupSession *session,
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/* base64-encoded keys; note that it will be overwritten with the base64-decoded
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data. */
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uint8_t const * session_key, size_t session_key_length
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);
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/**
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* Get an upper bound on the number of bytes of plain-text the decrypt method
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* will write for a given input message length. The actual size could be
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@ -165,6 +183,50 @@ size_t olm_inbound_group_session_id(
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uint8_t * id, size_t id_length
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);
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/**
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* Get the first message index we know how to decrypt.
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*/
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uint32_t olm_inbound_group_session_first_known_index(
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const OlmInboundGroupSession *session
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);
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/**
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* Check if the session has been verified as a valid session.
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*
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* (A session is verified either because the original session share was signed,
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* or because we have subsequently successfully decrypted a message.)
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*
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* This is mainly intended for the unit tests, currently.
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*/
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int olm_inbound_group_session_is_verified(
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const OlmInboundGroupSession *session
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);
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/**
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* Get the number of bytes returned by olm_export_inbound_group_session()
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*/
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size_t olm_export_inbound_group_session_length(
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const OlmInboundGroupSession *session
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);
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/**
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* Export the base64-encoded ratchet key for this session, at the given index,
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* in a format which can be used by olm_import_inbound_group_session
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*
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* Returns the length of the ratchet key on success or olm_error() on
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* failure. On failure last_error will be set with an error code. The
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* last_error will be:
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* * OUTPUT_BUFFER_TOO_SMALL if the buffer was too small
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* * OLM_UNKNOWN_MESSAGE_INDEX if we do not have a session key corresponding to the
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* given index (ie, it was sent before the session key was shared with
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* us)
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*/
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size_t olm_export_inbound_group_session(
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OlmInboundGroupSession *session,
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uint8_t * key, size_t key_length, uint32_t message_index
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);
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#ifdef __cplusplus
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} // extern "C"
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@ -61,6 +61,15 @@ InboundGroupSession.prototype['create'] = restore_stack(function(session_key) {
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);
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});
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InboundGroupSession.prototype['import_session'] = restore_stack(function(session_key) {
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var key_array = array_from_string(session_key);
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var key_buffer = stack(key_array);
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inbound_group_session_method(Module['_olm_import_inbound_group_session'])(
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this.ptr, key_buffer, key_array.length
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);
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});
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InboundGroupSession.prototype['decrypt'] = restore_stack(function(
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message
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) {
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@ -123,4 +132,21 @@ InboundGroupSession.prototype['session_id'] = restore_stack(function() {
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return Pointer_stringify(session_id);
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});
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InboundGroupSession.prototype['first_known_index'] = restore_stack(function() {
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return inbound_group_session_method(
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Module['_olm_inbound_group_session_first_known_index']
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)(this.ptr);
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});
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InboundGroupSession.prototype['export_session'] = restore_stack(function(message_index) {
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var key_length = inbound_group_session_method(
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Module['_olm_export_inbound_group_session_length']
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)(this.ptr);
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var key = stack(key_length + NULL_BYTE_PADDING_LENGTH);
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outbound_group_session_method(Module['_olm_export_inbound_group_session'])(
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this.ptr, key, key_length, message_index
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);
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return Pointer_stringify(key);
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});
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olm_exports['InboundGroupSession'] = InboundGroupSession;
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1
python/.gitignore
vendored
1
python/.gitignore
vendored
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@ -2,3 +2,4 @@
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/*.account
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/*.session
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/*.group_session
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/group_message
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@ -268,6 +268,19 @@ def build_arg_parser():
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default=sys.stdin)
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inbound_group.set_defaults(func=do_inbound_group)
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import_inbound_group = commands.add_parser(
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"import_inbound_group",
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help="Create an inbound group session based an exported inbound group"
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)
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import_inbound_group.add_argument("session_file", help="Local inbound group session file")
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import_inbound_group.add_argument(
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"export_file",
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help="File to read credentials from (default stdin)",
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type=argparse.FileType('r'), nargs='?',
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default=sys.stdin,
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)
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import_inbound_group.set_defaults(func=do_import_inbound_group)
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group_decrypt = commands.add_parser("group_decrypt", help="Decrypt a group message")
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group_decrypt.add_argument("session_file", help="Local inbound group session file")
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group_decrypt.add_argument("message_file", help="Message file (default stdin)",
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@ -277,6 +290,27 @@ def build_arg_parser():
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type=argparse.FileType('wb'), nargs='?',
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default=sys.stdout)
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group_decrypt.set_defaults(func=do_group_decrypt)
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export_inbound_group = commands.add_parser(
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"export_inbound_group",
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help="Export the keys for an inbound group session",
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)
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export_inbound_group.add_argument(
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"session_file", help="Local inbound group session file",
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)
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export_inbound_group.add_argument(
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"export_file", help="File to export to (default stdout)",
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type=argparse.FileType('w'), nargs='?',
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default=sys.stdout,
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)
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export_inbound_group.add_argument(
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"--message_index",
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help="Index to export session at. Defaults to the earliest known index",
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type=int,
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)
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export_inbound_group.set_defaults(func=do_export_inbound_group)
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return parser
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def do_outbound_group(args):
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@ -324,6 +358,19 @@ def do_inbound_group(args):
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with open(args.session_file, "wb") as f:
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f.write(session.pickle(args.key))
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def do_import_inbound_group(args):
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if os.path.exists(args.session_file):
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sys.stderr.write("Session %r file already exists\n" % (
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args.session_file,
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))
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sys.exit(1)
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data = args.export_file.read().translate(None, "\r\n")
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session = InboundGroupSession()
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session.import_session(data)
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with open(args.session_file, "wb") as f:
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f.write(session.pickle(args.key))
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def do_group_decrypt(args):
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session = InboundGroupSession()
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session.unpickle(args.key, read_base64_file(args.session_file))
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@ -333,6 +380,15 @@ def do_group_decrypt(args):
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f.write(session.pickle(args.key))
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args.plaintext_file.write(plaintext)
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def do_export_inbound_group(args):
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session = InboundGroupSession()
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session.unpickle(args.key, read_base64_file(args.session_file))
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index = args.message_index
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if index is None:
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# default to first known index
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index = session.first_known_index()
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args.export_file.write(session.export_session(index))
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if __name__ == '__main__':
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parser = build_arg_parser()
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args = parser.parse_args()
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@ -36,6 +36,10 @@ inbound_group_session_function(
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lib.olm_init_inbound_group_session, c_void_p, c_size_t
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)
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inbound_group_session_function(
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lib.olm_import_inbound_group_session, c_void_p, c_size_t
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)
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inbound_group_session_function(
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lib.olm_group_decrypt_max_plaintext_length, c_void_p, c_size_t
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)
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@ -49,6 +53,13 @@ inbound_group_session_function(
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inbound_group_session_function(lib.olm_inbound_group_session_id_length)
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inbound_group_session_function(lib.olm_inbound_group_session_id, c_void_p, c_size_t)
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lib.olm_inbound_group_session_first_known_index.argtypes = (c_void_p,)
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lib.olm_inbound_group_session_first_known_index.restypes = c_uint32
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inbound_group_session_function(lib.olm_export_inbound_group_session_length)
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inbound_group_session_function(lib.olm_export_inbound_group_session, c_void_p, c_size_t, c_uint32)
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class InboundGroupSession(object):
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def __init__(self):
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self.buf = create_string_buffer(lib.olm_inbound_group_session_size())
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@ -76,6 +87,12 @@ class InboundGroupSession(object):
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self.ptr, key_buffer, len(session_key)
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)
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def import_session(self, session_key):
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key_buffer = create_string_buffer(session_key)
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lib.olm_import_inbound_group_session(
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self.ptr, key_buffer, len(session_key)
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)
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def decrypt(self, message):
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message_buffer = create_string_buffer(message)
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max_plaintext_length = lib.olm_group_decrypt_max_plaintext_length(
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@ -95,5 +112,15 @@ class InboundGroupSession(object):
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def session_id(self):
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id_length = lib.olm_inbound_group_session_id_length(self.ptr)
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id_buffer = create_string_buffer(id_length)
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lib.olm_inbound_group_session_id(self.ptr, id_buffer, id_length);
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lib.olm_inbound_group_session_id(self.ptr, id_buffer, id_length)
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return id_buffer.raw
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def first_known_index(self):
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return lib.olm_inbound_group_session_first_known_index(self.ptr)
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def export_session(self, message_index):
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length = lib.olm_export_inbound_group_session_length(self.ptr)
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buffer = create_string_buffer(length)
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lib.olm_export_inbound_group_session(self.ptr, buffer, length,
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message_index)
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return buffer.raw
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@ -10,10 +10,11 @@ ALICE_GROUP_SESSION=alice.group_session
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BOB_ACCOUNT=bob.account
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BOB_SESSION=bob.session
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BOB_GROUP_SESSION=bob.group_session
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CHARLIE_GROUP_SESSION=charlie.group_session
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rm $ALICE_ACCOUNT $BOB_ACCOUNT
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rm $ALICE_SESSION $BOB_SESSION
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rm $ALICE_GROUP_SESSION $BOB_GROUP_SESSION
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rm -f $ALICE_ACCOUNT $BOB_ACCOUNT
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rm -f $ALICE_SESSION $BOB_SESSION
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rm -f $ALICE_GROUP_SESSION $BOB_GROUP_SESSION $CHARLIE_GROUP_SESSION
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$OLM create_account $ALICE_ACCOUNT
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$OLM create_account $BOB_ACCOUNT
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@ -31,4 +32,8 @@ echo "Hello world" | $OLM encrypt $ALICE_SESSION - - | $OLM inbound $BOB_ACCOUNT
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$OLM outbound_group $ALICE_GROUP_SESSION
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$OLM group_credentials $ALICE_GROUP_SESSION | $OLM inbound_group $BOB_GROUP_SESSION
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echo "Hello group" | $OLM group_encrypt $ALICE_GROUP_SESSION - - | $OLM group_decrypt $BOB_GROUP_SESSION
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echo "Hello group" | $OLM group_encrypt $ALICE_GROUP_SESSION - group_message
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$OLM group_decrypt $BOB_GROUP_SESSION group_message
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$OLM export_inbound_group $BOB_GROUP_SESSION | $OLM import_inbound_group $CHARLIE_GROUP_SESSION
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$OLM group_decrypt $CHARLIE_GROUP_SESSION group_message
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@ -30,8 +30,9 @@
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#define OLM_PROTOCOL_VERSION 3
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#define GROUP_SESSION_ID_LENGTH ED25519_PUBLIC_KEY_LENGTH
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#define PICKLE_VERSION 1
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#define PICKLE_VERSION 2
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#define SESSION_KEY_VERSION 2
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#define SESSION_EXPORT_VERSION 1
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struct OlmInboundGroupSession {
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/** our earliest known ratchet value */
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@ -43,6 +44,17 @@ struct OlmInboundGroupSession {
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/** The ed25519 signing key */
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struct _olm_ed25519_public_key signing_key;
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/**
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* Have we ever seen any evidence that this is a valid session?
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* (either because the original session share was signed, or because we
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* have subsequently successfully decrypted a message)
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*
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* (We don't do anything with this currently, but we may want to bear it in
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* mind when we consider handling key-shares for sessions we already know
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* about.)
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*/
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int signing_key_verified;
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enum OlmErrorCode last_error;
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};
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@ -71,19 +83,24 @@ size_t olm_clear_inbound_group_session(
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return sizeof(OlmInboundGroupSession);
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}
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#define SESSION_EXPORT_RAW_LENGTH \
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(1 + 4 + MEGOLM_RATCHET_LENGTH + ED25519_PUBLIC_KEY_LENGTH)
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#define SESSION_KEY_RAW_LENGTH \
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(1 + 4 + MEGOLM_RATCHET_LENGTH + ED25519_PUBLIC_KEY_LENGTH\
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+ ED25519_SIGNATURE_LENGTH)
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/** init the session keys from the un-base64-ed session keys */
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static size_t _init_group_session_keys(
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OlmInboundGroupSession *session,
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const uint8_t *key_buf
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const uint8_t *key_buf,
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int export_format
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) {
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const uint8_t expected_version =
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(export_format ? SESSION_EXPORT_VERSION : SESSION_KEY_VERSION);
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const uint8_t *ptr = key_buf;
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size_t version = *ptr++;
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if (version != SESSION_KEY_VERSION) {
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if (version != expected_version) {
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session->last_error = OLM_BAD_SESSION_KEY;
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return (size_t)-1;
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}
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|
@ -103,11 +120,15 @@ static size_t _init_group_session_keys(
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);
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ptr += ED25519_PUBLIC_KEY_LENGTH;
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if (!_olm_crypto_ed25519_verify(
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&session->signing_key, key_buf, ptr - key_buf, ptr
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)) {
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session->last_error = OLM_BAD_SIGNATURE;
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return (size_t)-1;
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if (!export_format) {
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if (!_olm_crypto_ed25519_verify(&session->signing_key, key_buf,
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ptr - key_buf, ptr)) {
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session->last_error = OLM_BAD_SIGNATURE;
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return (size_t)-1;
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}
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/* signed keyshare */
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session->signing_key_verified = 1;
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}
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return 0;
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}
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|
@ -131,11 +152,35 @@ size_t olm_init_inbound_group_session(
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}
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_olm_decode_base64(session_key, session_key_length, key_buf);
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result = _init_group_session_keys(session, key_buf);
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result = _init_group_session_keys(session, key_buf, 0);
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_olm_unset(key_buf, SESSION_KEY_RAW_LENGTH);
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return result;
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}
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size_t olm_import_inbound_group_session(
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OlmInboundGroupSession *session,
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const uint8_t * session_key, size_t session_key_length
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) {
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uint8_t key_buf[SESSION_EXPORT_RAW_LENGTH];
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size_t raw_length = _olm_decode_base64_length(session_key_length);
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size_t result;
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if (raw_length == (size_t)-1) {
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session->last_error = OLM_INVALID_BASE64;
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return (size_t)-1;
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}
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if (raw_length != SESSION_EXPORT_RAW_LENGTH) {
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session->last_error = OLM_BAD_SESSION_KEY;
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return (size_t)-1;
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}
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_olm_decode_base64(session_key, session_key_length, key_buf);
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result = _init_group_session_keys(session, key_buf, 1);
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_olm_unset(key_buf, SESSION_EXPORT_RAW_LENGTH);
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return result;
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}
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static size_t raw_pickle_length(
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const OlmInboundGroupSession *session
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) {
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|
@ -144,6 +189,7 @@ static size_t raw_pickle_length(
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length += megolm_pickle_length(&session->initial_ratchet);
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length += megolm_pickle_length(&session->latest_ratchet);
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length += _olm_pickle_ed25519_public_key_length(&session->signing_key);
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length += _olm_pickle_bool_length(session->signing_key_verified);
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return length;
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}
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|
@ -171,6 +217,7 @@ size_t olm_pickle_inbound_group_session(
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pos = megolm_pickle(&session->initial_ratchet, pos);
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pos = megolm_pickle(&session->latest_ratchet, pos);
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pos = _olm_pickle_ed25519_public_key(pos, &session->signing_key);
|
||||
pos = _olm_pickle_bool(pos, session->signing_key_verified);
|
||||
|
||||
return _olm_enc_output(key, key_length, pickled, raw_length);
|
||||
}
|
||||
|
@ -194,7 +241,7 @@ size_t olm_unpickle_inbound_group_session(
|
|||
pos = pickled;
|
||||
end = pos + raw_length;
|
||||
pos = _olm_unpickle_uint32(pos, end, &pickle_version);
|
||||
if (pickle_version != PICKLE_VERSION) {
|
||||
if (pickle_version < 1 || pickle_version > PICKLE_VERSION) {
|
||||
session->last_error = OLM_UNKNOWN_PICKLE_VERSION;
|
||||
return (size_t)-1;
|
||||
}
|
||||
|
@ -202,6 +249,14 @@ size_t olm_unpickle_inbound_group_session(
|
|||
pos = megolm_unpickle(&session->latest_ratchet, pos, end);
|
||||
pos = _olm_unpickle_ed25519_public_key(pos, end, &session->signing_key);
|
||||
|
||||
if (pickle_version == 1) {
|
||||
/* pickle v1 had no signing_key_verified field (all keyshares were
|
||||
* verified at import time) */
|
||||
session->signing_key_verified = 1;
|
||||
} else {
|
||||
pos = _olm_unpickle_bool(pos, end, &(session->signing_key_verified));
|
||||
}
|
||||
|
||||
if (end != pos) {
|
||||
/* We had the wrong number of bytes in the input. */
|
||||
session->last_error = OLM_CORRUPTED_PICKLE;
|
||||
|
@ -257,6 +312,32 @@ size_t olm_group_decrypt_max_plaintext_length(
|
|||
);
|
||||
}
|
||||
|
||||
/**
|
||||
* get a copy of the megolm ratchet, advanced
|
||||
* to the relevant index. Returns 0 on success, -1 on error
|
||||
*/
|
||||
static size_t _get_megolm(
|
||||
OlmInboundGroupSession *session, uint32_t message_index, Megolm *result
|
||||
) {
|
||||
/* pick a megolm instance to use. If we're at or beyond the latest ratchet
|
||||
* value, use that */
|
||||
if ((message_index - session->latest_ratchet.counter) < (1U << 31)) {
|
||||
megolm_advance_to(&session->latest_ratchet, message_index);
|
||||
*result = session->latest_ratchet;
|
||||
return 0;
|
||||
} else if ((message_index - session->initial_ratchet.counter) >= (1U << 31)) {
|
||||
/* the counter is before our intial ratchet - we can't decode this. */
|
||||
session->last_error = OLM_UNKNOWN_MESSAGE_INDEX;
|
||||
return (size_t)-1;
|
||||
} else {
|
||||
/* otherwise, start from the initial megolm. Take a copy so that we
|
||||
* don't overwrite the initial megolm */
|
||||
*result = session->initial_ratchet;
|
||||
megolm_advance_to(result, message_index);
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* decrypt an un-base64-ed message
|
||||
*/
|
||||
|
@ -268,8 +349,7 @@ static size_t _decrypt(
|
|||
) {
|
||||
struct _OlmDecodeGroupMessageResults decoded_results;
|
||||
size_t max_length, r;
|
||||
Megolm *megolm;
|
||||
Megolm tmp_megolm;
|
||||
Megolm megolm;
|
||||
|
||||
_olm_decode_group_message(
|
||||
message, message_length,
|
||||
|
@ -316,38 +396,30 @@ static size_t _decrypt(
|
|||
return (size_t)-1;
|
||||
}
|
||||
|
||||
/* pick a megolm instance to use. If we're at or beyond the latest ratchet
|
||||
* value, use that */
|
||||
if ((decoded_results.message_index - session->latest_ratchet.counter) < (1U << 31)) {
|
||||
megolm = &session->latest_ratchet;
|
||||
} else if ((decoded_results.message_index - session->initial_ratchet.counter) >= (1U << 31)) {
|
||||
/* the counter is before our intial ratchet - we can't decode this. */
|
||||
session->last_error = OLM_UNKNOWN_MESSAGE_INDEX;
|
||||
return (size_t)-1;
|
||||
} else {
|
||||
/* otherwise, start from the initial megolm. Take a copy so that we
|
||||
* don't overwrite the initial megolm */
|
||||
tmp_megolm = session->initial_ratchet;
|
||||
megolm = &tmp_megolm;
|
||||
r = _get_megolm(session, decoded_results.message_index, &megolm);
|
||||
if (r == (size_t)-1) {
|
||||
return r;
|
||||
}
|
||||
|
||||
megolm_advance_to(megolm, decoded_results.message_index);
|
||||
|
||||
/* now try checking the mac, and decrypting */
|
||||
r = megolm_cipher->ops->decrypt(
|
||||
megolm_cipher,
|
||||
megolm_get_data(megolm), MEGOLM_RATCHET_LENGTH,
|
||||
megolm_get_data(&megolm), MEGOLM_RATCHET_LENGTH,
|
||||
message, message_length,
|
||||
decoded_results.ciphertext, decoded_results.ciphertext_length,
|
||||
plaintext, max_plaintext_length
|
||||
);
|
||||
|
||||
_olm_unset(&tmp_megolm, sizeof(tmp_megolm));
|
||||
_olm_unset(&megolm, sizeof(megolm));
|
||||
if (r == (size_t)-1) {
|
||||
session->last_error = OLM_BAD_MESSAGE_MAC;
|
||||
return r;
|
||||
}
|
||||
|
||||
/* once we have successfully decrypted a message, set a flag to say the
|
||||
* session appears valid. */
|
||||
session->signing_key_verified = 1;
|
||||
|
||||
return r;
|
||||
}
|
||||
|
||||
|
@ -391,3 +463,62 @@ size_t olm_inbound_group_session_id(
|
|||
session->signing_key.public_key, GROUP_SESSION_ID_LENGTH, id
|
||||
);
|
||||
}
|
||||
|
||||
uint32_t olm_inbound_group_session_first_known_index(
|
||||
const OlmInboundGroupSession *session
|
||||
) {
|
||||
return session->initial_ratchet.counter;
|
||||
}
|
||||
|
||||
int olm_inbound_group_session_is_verified(
|
||||
const OlmInboundGroupSession *session
|
||||
) {
|
||||
return session->signing_key_verified;
|
||||
}
|
||||
|
||||
size_t olm_export_inbound_group_session_length(
|
||||
const OlmInboundGroupSession *session
|
||||
) {
|
||||
return _olm_encode_base64_length(SESSION_EXPORT_RAW_LENGTH);
|
||||
}
|
||||
|
||||
size_t olm_export_inbound_group_session(
|
||||
OlmInboundGroupSession *session,
|
||||
uint8_t * key, size_t key_length, uint32_t message_index
|
||||
) {
|
||||
uint8_t *raw;
|
||||
uint8_t *ptr;
|
||||
Megolm megolm;
|
||||
size_t r;
|
||||
size_t encoded_length = olm_export_inbound_group_session_length(session);
|
||||
|
||||
if (key_length < encoded_length) {
|
||||
session->last_error = OLM_OUTPUT_BUFFER_TOO_SMALL;
|
||||
return (size_t)-1;
|
||||
}
|
||||
|
||||
r = _get_megolm(session, message_index, &megolm);
|
||||
if (r == (size_t)-1) {
|
||||
return r;
|
||||
}
|
||||
|
||||
/* put the raw data at the end of the output buffer. */
|
||||
raw = ptr = key + encoded_length - SESSION_EXPORT_RAW_LENGTH;
|
||||
*ptr++ = SESSION_EXPORT_VERSION;
|
||||
|
||||
// Encode message index as a big endian 32-bit number.
|
||||
for (unsigned i = 0; i < 4; i++) {
|
||||
*ptr++ = 0xFF & (message_index >> 24); message_index <<= 8;
|
||||
}
|
||||
|
||||
memcpy(ptr, megolm_get_data(&megolm), MEGOLM_RATCHET_LENGTH);
|
||||
ptr += MEGOLM_RATCHET_LENGTH;
|
||||
|
||||
memcpy(
|
||||
ptr, session->signing_key.public_key,
|
||||
ED25519_PUBLIC_KEY_LENGTH
|
||||
);
|
||||
ptr += ED25519_PUBLIC_KEY_LENGTH;
|
||||
|
||||
return _olm_encode_base64(raw, SESSION_EXPORT_RAW_LENGTH, key);
|
||||
}
|
||||
|
|
|
@ -127,17 +127,18 @@ int main() {
|
|||
assert_equals(msglen, res);
|
||||
assert_equals(1U, olm_outbound_group_session_message_index(session));
|
||||
|
||||
|
||||
/* build the inbound session */
|
||||
size = olm_inbound_group_session_size();
|
||||
uint8_t inbound_session_memory[size];
|
||||
OlmInboundGroupSession *inbound_session =
|
||||
olm_inbound_group_session(inbound_session_memory);
|
||||
|
||||
assert_equals(0, olm_inbound_group_session_is_verified(inbound_session));
|
||||
|
||||
res = olm_init_inbound_group_session(
|
||||
inbound_session, session_key, session_key_len);
|
||||
assert_equals((size_t)0, res);
|
||||
|
||||
assert_equals(1, olm_inbound_group_session_is_verified(inbound_session));
|
||||
|
||||
/* Check the session ids */
|
||||
|
||||
|
@ -174,6 +175,85 @@ int main() {
|
|||
assert_equals(message_index, uint32_t(0));
|
||||
}
|
||||
|
||||
{
|
||||
TestCase test_case("Inbound group session export/import");
|
||||
|
||||
uint8_t session_key[] =
|
||||
"AgAAAAAwMTIzNDU2Nzg5QUJERUYwMTIzNDU2Nzg5QUJDREVGMDEyMzQ1Njc4OUFCREVGM"
|
||||
"DEyMzQ1Njc4OUFCQ0RFRjAxMjM0NTY3ODlBQkRFRjAxMjM0NTY3ODlBQkNERUYwMTIzND"
|
||||
"U2Nzg5QUJERUYwMTIzNDU2Nzg5QUJDREVGMDEyMw0bdg1BDq4Px/slBow06q8n/B9WBfw"
|
||||
"WYyNOB8DlUmXGGwrFmaSb9bR/eY8xgERrxmP07hFmD9uqA2p8PMHdnV5ysmgufE6oLZ5+"
|
||||
"8/mWQOW3VVTnDIlnwd8oHUYRuk8TCQ";
|
||||
|
||||
const uint8_t message[] =
|
||||
"AwgAEhAcbh6UpbByoyZxufQ+h2B+8XHMjhR69G8F4+qjMaFlnIXusJZX3r8LnRORG9T3D"
|
||||
"XFdbVuvIWrLyRfm4i8QRbe8VPwGRFG57B1CtmxanuP8bHtnnYqlwPsD";
|
||||
const std::size_t msglen = sizeof(message)-1;
|
||||
|
||||
/* init first inbound group session, and decrypt */
|
||||
std::size_t size = olm_inbound_group_session_size();
|
||||
uint8_t session_memory1[size];
|
||||
OlmInboundGroupSession *session1 =
|
||||
olm_inbound_group_session(session_memory1);
|
||||
assert_equals(0, olm_inbound_group_session_is_verified(session1));
|
||||
|
||||
std::size_t res = olm_init_inbound_group_session(
|
||||
session1, session_key, sizeof(session_key)-1
|
||||
);
|
||||
assert_equals((size_t)0, res);
|
||||
assert_equals(1, olm_inbound_group_session_is_verified(session1));
|
||||
|
||||
/* olm_group_decrypt_max_plaintext_length destroys the input so we have to
|
||||
copy it. */
|
||||
uint8_t msgcopy[msglen];
|
||||
memcpy(msgcopy, message, msglen);
|
||||
size = olm_group_decrypt_max_plaintext_length(session1, msgcopy, msglen);
|
||||
uint8_t plaintext_buf[size];
|
||||
uint32_t message_index;
|
||||
memcpy(msgcopy, message, msglen);
|
||||
res = olm_group_decrypt(
|
||||
session1, msgcopy, msglen, plaintext_buf, size, &message_index
|
||||
);
|
||||
assert_equals((std::size_t)7, res);
|
||||
assert_equals((const uint8_t *)"Message", plaintext_buf, res);
|
||||
assert_equals(uint32_t(0), message_index);
|
||||
|
||||
/* export the keys */
|
||||
size = olm_export_inbound_group_session_length(session1);
|
||||
uint8_t export_memory[size];
|
||||
res = olm_export_inbound_group_session(
|
||||
session1, export_memory, size, 0
|
||||
);
|
||||
assert_equals(size, res);
|
||||
|
||||
/* free the old session to check there is no shared data */
|
||||
olm_clear_inbound_group_session(session1);
|
||||
|
||||
/* import the keys into another inbound group session */
|
||||
size = olm_inbound_group_session_size();
|
||||
uint8_t session_memory2[size];
|
||||
OlmInboundGroupSession *session2 =
|
||||
olm_inbound_group_session(session_memory2);
|
||||
res = olm_import_inbound_group_session(
|
||||
session2, export_memory, sizeof(export_memory)
|
||||
);
|
||||
assert_equals((size_t)0, res);
|
||||
assert_equals(0, olm_inbound_group_session_is_verified(session2));
|
||||
|
||||
/* decrypt the message with the new session */
|
||||
memcpy(msgcopy, message, msglen);
|
||||
size = olm_group_decrypt_max_plaintext_length(session2, msgcopy, msglen);
|
||||
uint8_t plaintext_buf2[size];
|
||||
memcpy(msgcopy, message, msglen);
|
||||
res = olm_group_decrypt(
|
||||
session2, msgcopy, msglen, plaintext_buf2, size, &message_index
|
||||
);
|
||||
assert_equals((std::size_t)7, res);
|
||||
assert_equals((const uint8_t *)"Message", plaintext_buf2, res);
|
||||
assert_equals(uint32_t(0), message_index);
|
||||
assert_equals(1, olm_inbound_group_session_is_verified(session2));
|
||||
}
|
||||
|
||||
{
|
||||
TestCase test_case("Invalid signature group message");
|
||||
|
||||
|
|
Loading…
Reference in a new issue