diff options
Diffstat (limited to 'paramiko/transport.py')
| -rw-r--r-- | paramiko/transport.py | 27 |
1 files changed, 22 insertions, 5 deletions
diff --git a/paramiko/transport.py b/paramiko/transport.py index 36da3043..31c27a2f 100644 --- a/paramiko/transport.py +++ b/paramiko/transport.py @@ -295,6 +295,8 @@ class Transport (threading.Thread, ClosingContextManager): self.global_response = None # response Message from an arbitrary global request self.completion_event = None # user-defined event callbacks self.banner_timeout = 15 # how long (seconds) to wait for the SSH banner + self.handshake_timeout = 15 # how long (seconds) to wait for the handshake to finish after SSH banner sent. + # server mode: self.server_mode = False @@ -587,7 +589,7 @@ class Transport (threading.Thread, ClosingContextManager): """ return self.active - def open_session(self, window_size=None, max_packet_size=None): + def open_session(self, window_size=None, max_packet_size=None, timeout=None): """ Request a new channel to the server, of type ``"session"``. This is just an alias for calling `open_channel` with an argument of @@ -612,7 +614,8 @@ class Transport (threading.Thread, ClosingContextManager): """ return self.open_channel('session', window_size=window_size, - max_packet_size=max_packet_size) + max_packet_size=max_packet_size, + timeout=timeout) def open_x11_channel(self, src_addr=None): """ @@ -659,7 +662,8 @@ class Transport (threading.Thread, ClosingContextManager): dest_addr=None, src_addr=None, window_size=None, - max_packet_size=None): + max_packet_size=None, + timeout=None): """ Request a new channel to the server. `Channels <.Channel>` are socket-like objects used for the actual transfer of data across the @@ -683,17 +687,20 @@ class Transport (threading.Thread, ClosingContextManager): optional window size for this session. :param int max_packet_size: optional max packet size for this session. + :param float timeout: + optional timeout opening a channel, default 3600s (1h) :return: a new `.Channel` on success - :raises SSHException: if the request is rejected or the session ends - prematurely + :raises SSHException: if the request is rejected, the session ends + prematurely or there is a timeout openning a channel .. versionchanged:: 1.15 Added the ``window_size`` and ``max_packet_size`` arguments. """ if not self.active: raise SSHException('SSH session not active') + timeout = 3600 if timeout is None else timeout self.lock.acquire() try: window_size = self._sanitize_window_size(window_size) @@ -722,6 +729,7 @@ class Transport (threading.Thread, ClosingContextManager): finally: self.lock.release() self._send_user_message(m) + start_ts = time.time() while True: event.wait(0.1) if not self.active: @@ -731,6 +739,8 @@ class Transport (threading.Thread, ClosingContextManager): raise e if event.is_set(): break + elif start_ts + timeout < time.time(): + raise SSHException('Timeout openning channel.') chan = self._channels.get(chanid) if chan is not None: return chan @@ -1582,6 +1592,12 @@ class Transport (threading.Thread, ClosingContextManager): try: self.packetizer.write_all(b(self.local_version + '\r\n')) self._check_banner() + # The above is actually very much part of the handshake, but sometimes the banner can be read + # but the machine is not responding, for example when the remote ssh daemon is loaded in to memory + # but we can not read from the disk/spawn a new shell. + # Make sure we can specify a timeout for the initial handshake. + # Re-use the banner timeout for now. + self.packetizer.start_handshake(self.handshake_timeout) self._send_kex_init() self._expect_packet(MSG_KEXINIT) @@ -1631,6 +1647,7 @@ class Transport (threading.Thread, ClosingContextManager): msg.add_byte(cMSG_UNIMPLEMENTED) msg.add_int(m.seqno) self._send_message(msg) + self.packetizer.complete_handshake() except SSHException as e: self._log(ERROR, 'Exception: ' + str(e)) self._log(ERROR, util.tb_strings()) |