# -*- test-case-name: twisted.conch.test.test_conch -*- # # Copyright (c) Twisted Matrix Laboratories. # See LICENSE for details. # # $Id: conch.py,v 1.65 2004/03/11 00:29:14 z3p Exp $ #""" Implementation module for the `conch` command. #""" from __future__ import print_function from twisted.conch.client import connect, default, options from twisted.conch.error import ConchError from twisted.conch.ssh import connection, common from twisted.conch.ssh import session, forwarding, channel from twisted.internet import reactor, stdio, task from twisted.python import log, usage from twisted.python.compat import ioType, networkString, unicode import os import sys import getpass import struct import tty import fcntl import signal class ClientOptions(options.ConchOptions): synopsis = """Usage: conch [options] host [command] """ longdesc = ("conch is a SSHv2 client that allows logging into a remote " "machine and executing commands.") optParameters = [['escape', 'e', '~'], ['localforward', 'L', None, 'listen-port:host:port Forward local port to remote address'], ['remoteforward', 'R', None, 'listen-port:host:port Forward remote port to local address'], ] optFlags = [['null', 'n', 'Redirect input from /dev/null.'], ['fork', 'f', 'Fork to background after authentication.'], ['tty', 't', 'Tty; allocate a tty even if command is given.'], ['notty', 'T', 'Do not allocate a tty.'], ['noshell', 'N', 'Do not execute a shell or command.'], ['subsystem', 's', 'Invoke command (mandatory) as SSH2 subsystem.'], ] compData = usage.Completions( mutuallyExclusive=[("tty", "notty")], optActions={ "localforward": usage.Completer(descr="listen-port:host:port"), "remoteforward": usage.Completer(descr="listen-port:host:port")}, extraActions=[usage.CompleteUserAtHost(), usage.Completer(descr="command"), usage.Completer(descr="argument", repeat=True)] ) localForwards = [] remoteForwards = [] def opt_escape(self, esc): """ Set escape character; ``none'' = disable """ if esc == 'none': self['escape'] = None elif esc[0] == '^' and len(esc) == 2: self['escape'] = chr(ord(esc[1])-64) elif len(esc) == 1: self['escape'] = esc else: sys.exit("Bad escape character '{}'.".format(esc)) def opt_localforward(self, f): """ Forward local port to remote address (lport:host:port) """ localPort, remoteHost, remotePort = f.split(':') # Doesn't do v6 yet localPort = int(localPort) remotePort = int(remotePort) self.localForwards.append((localPort, (remoteHost, remotePort))) def opt_remoteforward(self, f): """ Forward remote port to local address (rport:host:port) """ remotePort, connHost, connPort = f.split(':') # Doesn't do v6 yet remotePort = int(remotePort) connPort = int(connPort) self.remoteForwards.append((remotePort, (connHost, connPort))) def parseArgs(self, host, *command): self['host'] = host self['command'] = ' '.join(command) # Rest of code in "run" options = None conn = None exitStatus = 0 old = None _inRawMode = 0 _savedRawMode = None def run(): global options, old args = sys.argv[1:] if '-l' in args: # CVS is an idiot i = args.index('-l') args = args[i:i+2]+args del args[i+2:i+4] for arg in args[:]: try: i = args.index(arg) if arg[:2] == '-o' and args[i+1][0] != '-': args[i:i+2] = [] # Suck on it scp except ValueError: pass options = ClientOptions() try: options.parseOptions(args) except usage.UsageError as u: print('ERROR: {}'.format(u)) options.opt_help() sys.exit(1) if options['log']: if options['logfile']: if options['logfile'] == '-': f = sys.stdout else: f = open(options['logfile'], 'a+') else: f = sys.stderr realout = sys.stdout log.startLogging(f) sys.stdout = realout else: log.discardLogs() doConnect() fd = sys.stdin.fileno() try: old = tty.tcgetattr(fd) except: old = None try: oldUSR1 = signal.signal(signal.SIGUSR1, lambda *a: reactor.callLater(0, reConnect)) except: oldUSR1 = None try: reactor.run() finally: if old: tty.tcsetattr(fd, tty.TCSANOW, old) if oldUSR1: signal.signal(signal.SIGUSR1, oldUSR1) if (options['command'] and options['tty']) or not options['notty']: signal.signal(signal.SIGWINCH, signal.SIG_DFL) if sys.stdout.isatty() and not options['command']: print('Connection to {} closed.'.format(options['host'])) sys.exit(exitStatus) def handleError(): from twisted.python import failure global exitStatus exitStatus = 2 reactor.callLater(0.01, _stopReactor) log.err(failure.Failure()) raise def _stopReactor(): try: reactor.stop() except: pass def doConnect(): if '@' in options['host']: options['user'], options['host'] = options['host'].split('@', 1) if not options.identitys: options.identitys = ['~/.ssh/id_rsa', '~/.ssh/id_dsa'] host = options['host'] if not options['user']: options['user'] = getpass.getuser() if not options['port']: options['port'] = 22 else: options['port'] = int(options['port']) host = options['host'] port = options['port'] vhk = default.verifyHostKey if not options['host-key-algorithms']: options['host-key-algorithms'] = default.getHostKeyAlgorithms( host, options) uao = default.SSHUserAuthClient(options['user'], options, SSHConnection()) connect.connect(host, port, options, vhk, uao).addErrback(_ebExit) def _ebExit(f): global exitStatus exitStatus = "conch: exiting with error {}".format(f) reactor.callLater(0.1, _stopReactor) def onConnect(): # if keyAgent and options['agent']: # cc = protocol.ClientCreator(reactor, SSHAgentForwardingLocal, conn) # cc.connectUNIX(os.environ['SSH_AUTH_SOCK']) if hasattr(conn.transport, 'sendIgnore'): _KeepAlive(conn) if options.localForwards: for localPort, hostport in options.localForwards: s = reactor.listenTCP(localPort, forwarding.SSHListenForwardingFactory(conn, hostport, SSHListenClientForwardingChannel)) conn.localForwards.append(s) if options.remoteForwards: for remotePort, hostport in options.remoteForwards: log.msg('asking for remote forwarding for {}:{}'.format( remotePort, hostport)) conn.requestRemoteForwarding(remotePort, hostport) reactor.addSystemEventTrigger('before', 'shutdown', beforeShutdown) if not options['noshell'] or options['agent']: conn.openChannel(SSHSession()) if options['fork']: if os.fork(): os._exit(0) os.setsid() for i in range(3): try: os.close(i) except OSError as e: import errno if e.errno != errno.EBADF: raise def reConnect(): beforeShutdown() conn.transport.transport.loseConnection() def beforeShutdown(): remoteForwards = options.remoteForwards for remotePort, hostport in remoteForwards: log.msg('cancelling {}:{}'.format(remotePort, hostport)) conn.cancelRemoteForwarding(remotePort) def stopConnection(): if not options['reconnect']: reactor.callLater(0.1, _stopReactor) class _KeepAlive: def __init__(self, conn): self.conn = conn self.globalTimeout = None self.lc = task.LoopingCall(self.sendGlobal) self.lc.start(300) def sendGlobal(self): d = self.conn.sendGlobalRequest(b"conch-keep-alive@twistedmatrix.com", b"", wantReply=1) d.addBoth(self._cbGlobal) self.globalTimeout = reactor.callLater(30, self._ebGlobal) def _cbGlobal(self, res): if self.globalTimeout: self.globalTimeout.cancel() self.globalTimeout = None def _ebGlobal(self): if self.globalTimeout: self.globalTimeout = None self.conn.transport.loseConnection() class SSHConnection(connection.SSHConnection): def serviceStarted(self): global conn conn = self self.localForwards = [] self.remoteForwards = {} if not isinstance(self, connection.SSHConnection): # make these fall through del self.__class__.requestRemoteForwarding del self.__class__.cancelRemoteForwarding onConnect() def serviceStopped(self): lf = self.localForwards self.localForwards = [] for s in lf: s.loseConnection() stopConnection() def requestRemoteForwarding(self, remotePort, hostport): data = forwarding.packGlobal_tcpip_forward(('0.0.0.0', remotePort)) d = self.sendGlobalRequest(b'tcpip-forward', data, wantReply=1) log.msg('requesting remote forwarding {}:{}'.format( remotePort, hostport)) d.addCallback(self._cbRemoteForwarding, remotePort, hostport) d.addErrback(self._ebRemoteForwarding, remotePort, hostport) def _cbRemoteForwarding(self, result, remotePort, hostport): log.msg('accepted remote forwarding {}:{}'.format( remotePort, hostport)) self.remoteForwards[remotePort] = hostport log.msg(repr(self.remoteForwards)) def _ebRemoteForwarding(self, f, remotePort, hostport): log.msg('remote forwarding {}:{} failed'.format( remotePort, hostport)) log.msg(f) def cancelRemoteForwarding(self, remotePort): data = forwarding.packGlobal_tcpip_forward(('0.0.0.0', remotePort)) self.sendGlobalRequest(b'cancel-tcpip-forward', data) log.msg('cancelling remote forwarding {}'.format(remotePort)) try: del self.remoteForwards[remotePort] except Exception: pass log.msg(repr(self.remoteForwards)) def channel_forwarded_tcpip(self, windowSize, maxPacket, data): log.msg('FTCP {!r}'.format(data)) remoteHP, origHP = forwarding.unpackOpen_forwarded_tcpip(data) log.msg(self.remoteForwards) log.msg(remoteHP) if remoteHP[1] in self.remoteForwards: connectHP = self.remoteForwards[remoteHP[1]] log.msg('connect forwarding {}'.format(connectHP)) return SSHConnectForwardingChannel(connectHP, remoteWindow=windowSize, remoteMaxPacket=maxPacket, conn=self) else: raise ConchError(connection.OPEN_CONNECT_FAILED, "don't know about that port") def channelClosed(self, channel): log.msg('connection closing {}'.format(channel)) log.msg(self.channels) if len(self.channels) == 1: # Just us left log.msg('stopping connection') stopConnection() else: # Because of the unix thing self.__class__.__bases__[0].channelClosed(self, channel) class SSHSession(channel.SSHChannel): name = b'session' def channelOpen(self, foo): log.msg('session {} open'.format(self.id)) if options['agent']: d = self.conn.sendRequest(self, b'auth-agent-req@openssh.com', b'', wantReply=1) d.addBoth(lambda x: log.msg(x)) if options['noshell']: return if (options['command'] and options['tty']) or not options['notty']: _enterRawMode() c = session.SSHSessionClient() if options['escape'] and not options['notty']: self.escapeMode = 1 c.dataReceived = self.handleInput else: c.dataReceived = self.write c.connectionLost = lambda x: self.sendEOF() self.stdio = stdio.StandardIO(c) fd = 0 if options['subsystem']: self.conn.sendRequest(self, b'subsystem', common.NS(options['command'])) elif options['command']: if options['tty']: term = os.environ['TERM'] winsz = fcntl.ioctl(fd, tty.TIOCGWINSZ, '12345678') winSize = struct.unpack('4H', winsz) ptyReqData = session.packRequest_pty_req(term, winSize, '') self.conn.sendRequest(self, b'pty-req', ptyReqData) signal.signal(signal.SIGWINCH, self._windowResized) self.conn.sendRequest(self, b'exec', common.NS(options['command'])) else: if not options['notty']: term = os.environ['TERM'] winsz = fcntl.ioctl(fd, tty.TIOCGWINSZ, '12345678') winSize = struct.unpack('4H', winsz) ptyReqData = session.packRequest_pty_req(term, winSize, '') self.conn.sendRequest(self, b'pty-req', ptyReqData) signal.signal(signal.SIGWINCH, self._windowResized) self.conn.sendRequest(self, b'shell', b'') #if hasattr(conn.transport, 'transport'): # conn.transport.transport.setTcpNoDelay(1) def handleInput(self, char): if char in (b'\n', b'\r'): self.escapeMode = 1 self.write(char) elif self.escapeMode == 1 and char == options['escape']: self.escapeMode = 2 elif self.escapeMode == 2: self.escapeMode = 1 # So we can chain escapes together if char == b'.': # Disconnect log.msg('disconnecting from escape') stopConnection() return elif char == b'\x1a': # ^Z, suspend def _(): _leaveRawMode() sys.stdout.flush() sys.stdin.flush() os.kill(os.getpid(), signal.SIGTSTP) _enterRawMode() reactor.callLater(0, _) return elif char == b'R': # Rekey connection log.msg('rekeying connection') self.conn.transport.sendKexInit() return elif char == b'#': # Display connections self.stdio.write( b'\r\nThe following connections are open:\r\n') channels = self.conn.channels.keys() channels.sort() for channelId in channels: self.stdio.write(networkString(' #{} {}\r\n'.format( channelId, self.conn.channels[channelId]))) return self.write(b'~' + char) else: self.escapeMode = 0 self.write(char) def dataReceived(self, data): self.stdio.write(data) def extReceived(self, t, data): if t == connection.EXTENDED_DATA_STDERR: log.msg('got {} stderr data'.format(len(data))) if ioType(sys.stderr) == unicode: sys.stderr.buffer.write(data) else: sys.stderr.write(data) def eofReceived(self): log.msg('got eof') self.stdio.loseWriteConnection() def closeReceived(self): log.msg('remote side closed {}'.format(self)) self.conn.sendClose(self) def closed(self): global old log.msg('closed {}'.format(self)) log.msg(repr(self.conn.channels)) def request_exit_status(self, data): global exitStatus exitStatus = int(struct.unpack('>L', data)[0]) log.msg('exit status: {}'.format(exitStatus)) def sendEOF(self): self.conn.sendEOF(self) def stopWriting(self): self.stdio.pauseProducing() def startWriting(self): self.stdio.resumeProducing() def _windowResized(self, *args): winsz = fcntl.ioctl(0, tty.TIOCGWINSZ, '12345678') winSize = struct.unpack('4H', winsz) newSize = winSize[1], winSize[0], winSize[2], winSize[3] self.conn.sendRequest(self, b'window-change', struct.pack('!4L', *newSize)) class SSHListenClientForwardingChannel(forwarding.SSHListenClientForwardingChannel): pass class SSHConnectForwardingChannel(forwarding.SSHConnectForwardingChannel): pass def _leaveRawMode(): global _inRawMode if not _inRawMode: return fd = sys.stdin.fileno() tty.tcsetattr(fd, tty.TCSANOW, _savedRawMode) _inRawMode = 0 def _enterRawMode(): global _inRawMode, _savedRawMode if _inRawMode: return fd = sys.stdin.fileno() try: old = tty.tcgetattr(fd) new = old[:] except: log.msg('not a typewriter!') else: # iflage new[0] = new[0] | tty.IGNPAR new[0] = new[0] & ~(tty.ISTRIP | tty.INLCR | tty.IGNCR | tty.ICRNL | tty.IXON | tty.IXANY | tty.IXOFF) if hasattr(tty, 'IUCLC'): new[0] = new[0] & ~tty.IUCLC # lflag new[3] = new[3] & ~(tty.ISIG | tty.ICANON | tty.ECHO | tty.ECHO | tty.ECHOE | tty.ECHOK | tty.ECHONL) if hasattr(tty, 'IEXTEN'): new[3] = new[3] & ~tty.IEXTEN #oflag new[1] = new[1] & ~tty.OPOST new[6][tty.VMIN] = 1 new[6][tty.VTIME] = 0 _savedRawMode = old tty.tcsetattr(fd, tty.TCSANOW, new) #tty.setraw(fd) _inRawMode = 1 if __name__ == '__main__': run()