diff options
Diffstat (limited to 'demos/forward.py')
| -rw-r--r-- | demos/forward.py | 202 |
1 files changed, 80 insertions, 122 deletions
diff --git a/demos/forward.py b/demos/forward.py index 2809d815..c398e6ef 100644 --- a/demos/forward.py +++ b/demos/forward.py @@ -1,4 +1,4 @@ -#!/usr/bin/python +#!/usr/bin/env python # Copyright (C) 2003-2007 Robey Pointer <robey@lag.net> # @@ -37,10 +37,10 @@ from optparse import OptionParser import paramiko -DEFAULT_PORT = 4000 SSH_PORT = 22 -VERBOSE = True -READPASS = False +DEFAULT_PORT = 4000 + +g_verbose = True class ForwardServer (SocketServer.ThreadingTCPServer): @@ -65,7 +65,8 @@ class Handler (SocketServer.BaseRequestHandler): (self.chain_host, self.chain_port)) return - verbose('Connected! Tunnel open.') + verbose('Connected! Tunnel open %r -> %r -> %r' % (self.request.getpeername(), + chan.getpeername(), (self.chain_host, self.chain_port))) while True: r, w, x = select.select([self.request, chan], [], []) if self.request in r: @@ -80,7 +81,7 @@ class Handler (SocketServer.BaseRequestHandler): self.request.send(data) chan.close() self.request.close() - verbose('Tunnel closed.') + verbose('Tunnel closed from %r' % (self.request.getpeername(),)) def forward_tunnel(local_port, remote_host, remote_port, transport): @@ -93,131 +94,88 @@ def forward_tunnel(local_port, remote_host, remote_port, transport): ssh_transport = transport ForwardServer(('', local_port), SubHander).serve_forever() -def find_default_key_file(): - filename = os.path.expanduser('~/.ssh/id_rsa') - if os.access(filename, os.R_OK): - return filename - filename = os.path.expanduser('~/ssh/id_rsa') - if os.access(filename, os.R_OK): - return filename - filename = os.path.expanduser('~/.ssh/id_dsa') - if os.access(filename, os.R_OK): - return filename - filename = os.path.expanduser('~/ssh/id_dsa') - if os.access(filename, os.R_OK): - return filename - return '' def verbose(s): - if VERBOSE: + if g_verbose: print s -##### - - -parser = OptionParser(usage='usage: %prog [options] <remote-addr>:<remote-port>', - version='%prog 1.0') -parser.add_option('-q', '--quiet', action='store_false', dest='verbose', default=VERBOSE, - help='squelch all informational output') -parser.add_option('-l', '--local-port', action='store', type='int', dest='port', - default=DEFAULT_PORT, - help='local port to forward (default: %d)' % DEFAULT_PORT) -parser.add_option('-r', '--host', action='store', type='string', dest='ssh_host', - help='SSH host to tunnel through (required)') -parser.add_option('-p', '--port', action='store', type='int', dest='ssh_port', default=SSH_PORT, - help='SSH port to tunnel through (default: %d)' % SSH_PORT) -parser.add_option('-u', '--user', action='store', type='string', dest='user', - default=getpass.getuser(), - help='username for SSH authentication (default: %s)' % getpass.getuser()) -parser.add_option('-K', '--key', action='store', type='string', dest='keyfile', - default=find_default_key_file(), - help='private key file to use for SSH authentication') -parser.add_option('', '--no-key', action='store_false', dest='use_key', default=True, - help='don\'t look for or use a private key file') -parser.add_option('-P', '--password', action='store_true', dest='readpass', default=READPASS, - help='read password (for key or password auth) from stdin') -options, args = parser.parse_args() - -VERBOSE = options.verbose -READPASS = options.readpass - - -if len(args) != 1: - parser.error('Incorrect number of arguments.') -remote_host = args[0] -if ':' not in remote_host: - parser.error('Remote port missing.') -remote_host, remote_port = remote_host.split(':', 1) -try: - remote_port = int(remote_port) -except: - parser.error('Remote port must be a number.') - -if not options.ssh_host: - parser.error('SSH host is required.') -if ':' in options.ssh_host: - options.ssh_host, options.ssh_port = options.ssh_host.split(':', 1) - try: - options.ssh_port = int(options.ssh_port) - except: - parser.error('SSH port must be a number.') +HELP = """\ +Set up a forward tunnel across an SSH server, using paramiko. A local port +(given with -l) is forwarded across an SSH session to an address:port from +the SSH server. This is similar to the openssh -L option. +""" -try: - host_keys = paramiko.util.load_host_keys(os.path.expanduser('~/.ssh/known_hosts')) -except IOError: - try: - host_keys = paramiko.util.load_host_keys(os.path.expanduser('~/ssh/known_hosts')) - except IOError: - print '*** Unable to open host keys file' - host_keys = {} - -if not host_keys.has_key(options.ssh_host): - print '*** Warning: no host key for %s' % options.ssh_host - expected_host_key_type = None - expected_host_key = None -else: - expected_host_key_type = host_keys[options.ssh_host].keys()[0] - expected_host_key = host_keys[options.ssh_host][expected_host_key_type] - -key = None -password = None -if options.use_key: + +def get_host_port(spec, default_port): + "parse 'hostname:22' into a host and port, with the port optional" + args = (spec.split(':', 1) + [default_port])[:2] + args[1] = int(args[1]) + return args[0], args[1] + + +def parse_options(): + global g_verbose + + parser = OptionParser(usage='usage: %prog [options] <ssh-server>[:<server-port>]', + version='%prog 1.0', description=HELP) + parser.add_option('-q', '--quiet', action='store_false', dest='verbose', default=True, + help='squelch all informational output') + parser.add_option('-l', '--local-port', action='store', type='int', dest='port', + default=DEFAULT_PORT, + help='local port to forward (default: %d)' % DEFAULT_PORT) + parser.add_option('-u', '--user', action='store', type='string', dest='user', + default=getpass.getuser(), + help='username for SSH authentication (default: %s)' % getpass.getuser()) + parser.add_option('-K', '--key', action='store', type='string', dest='keyfile', + default=None, + help='private key file to use for SSH authentication') + parser.add_option('', '--no-key', action='store_false', dest='look_for_keys', default=True, + help='don\'t look for or use a private key file') + parser.add_option('-P', '--password', action='store_true', dest='readpass', default=False, + help='read password (for key or password auth) from stdin') + parser.add_option('-r', '--remote', action='store', type='string', dest='remote', default=None, metavar='host:port', + help='remote host and port to forward to') + options, args = parser.parse_args() + + if len(args) != 1: + parser.error('Incorrect number of arguments.') + if options.remote is None: + parser.error('Remote address required (-r).') + + g_verbose = options.verbose + server_host, server_port = get_host_port(args[0], SSH_PORT) + remote_host, remote_port = get_host_port(options.remote, SSH_PORT) + return options, (server_host, server_port), (remote_host, remote_port) + + +def main(): + options, server, remote = parse_options() + + password = None + if options.readpass: + password = getpass.getpass('Enter SSH password: ') + + client = paramiko.SSHClient() + client.load_system_host_keys() + client.set_missing_host_key_policy(paramiko.WarningPolicy()) + + verbose('Connecting to ssh host %s:%d ...' % (server[0], server[1])) try: - key = paramiko.RSAKey.from_private_key_file(options.keyfile) - except paramiko.PasswordRequiredException: - if not READPASS: - print '*** Password needed for keyfile (use -P): %s' % options.keyfile - sys.exit(1) - key_password = getpass.getpass('Enter password for key: ') - try: - key = paramiko.RSAKey.from_private_key_file(options.keyfile, key_password) - except: - print '*** Unable to read keyfile: %s' % options.keyfile - sys.exit(1) - except: - pass - -if key is None: - # try reading a password then - if not READPASS: - print '*** Either a valid private key or password is required (use -K or -P).' + client.connect(server[0], server[1], username=options.user, key_filename=options.keyfile, + look_for_keys=options.look_for_keys, password=password) + except Exception, e: + print '*** Failed to connect to %s:%d: %r' % (server[0], server[1], e) sys.exit(1) - password = getpass.getpass('Enter password: ') -verbose('Connecting to ssh host %s:%d ...' % (options.ssh_host, options.ssh_port)) + verbose('Now forwarding port %d to %s:%d ...' % (options.port, remote[0], remote[1])) -transport = paramiko.Transport((options.ssh_host, options.ssh_port)) -transport.connect(hostkeytype=expected_host_key_type, - hostkey=expected_host_key, - username=options.user, - password=password, - pkey=key) + try: + forward_tunnel(options.port, remote[0], remote[1], client.get_transport()) + except KeyboardInterrupt: + print 'C-c: Port forwarding stopped.' + sys.exit(0) -verbose('Now forwarding port %d to %s:%d ...' % (options.port, remote_host, remote_port)) -try: - forward_tunnel(options.port, remote_host, remote_port, transport) -except KeyboardInterrupt: - print 'Port forwarding stopped.' - sys.exit(0) +if __name__ == '__main__': + main() |