1
# Copyright (C) 2006-2010 Robey Pointer <robey@lag.net>
1
# Copyright (C) 2005 Robey Pointer <robey@lag.net>
2
2
# Copyright (C) 2005, 2006, 2007 Canonical Ltd
4
4
# This program is free software; you can redistribute it and/or modify
14
14
# You should have received a copy of the GNU General Public License
15
15
# along with this program; if not, write to the Free Software
16
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
16
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18
18
"""Foundation SSH support for SFTP and smart server."""
95
94
vendor = self._ssh_vendors[vendor_name]
97
vendor = self._get_vendor_from_path(vendor_name)
99
raise errors.UnknownSSH(vendor_name)
100
vendor.executable_path = vendor_name
96
raise errors.UnknownSSH(vendor_name)
113
109
stdout = stderr = ''
114
110
return stdout + stderr
116
def _get_vendor_by_version_string(self, version, progname):
112
def _get_vendor_by_version_string(self, version, args):
117
113
"""Return the vendor or None based on output from the subprocess.
119
115
:param version: The output of 'ssh -V' like command.
126
122
elif 'SSH Secure Shell' in version:
127
123
trace.mutter('ssh implementation is SSH Corp.')
128
124
vendor = SSHCorpSubprocessVendor()
129
# As plink user prompts are not handled currently, don't auto-detect
130
# it by inspection below, but keep this vendor detection for if a path
131
# is given in BZR_SSH. See https://bugs.launchpad.net/bugs/414743
132
elif 'plink' in version and progname == 'plink':
125
elif 'plink' in version and args[0] == 'plink':
133
126
# Checking if "plink" was the executed argument as Windows
134
127
# sometimes reports 'ssh -V' incorrectly with 'plink' in it's
135
128
# version. See https://bugs.launchpad.net/bzr/+bug/107155
140
133
def _get_vendor_by_inspection(self):
141
134
"""Return the vendor or None by checking for known SSH implementations."""
142
version = self._get_ssh_version_string(['ssh', '-V'])
143
return self._get_vendor_by_version_string(version, "ssh")
145
def _get_vendor_from_path(self, path):
146
"""Return the vendor or None using the program at the given path"""
147
version = self._get_ssh_version_string([path, '-V'])
148
return self._get_vendor_by_version_string(version,
149
os.path.splitext(os.path.basename(path))[0])
135
# detection of plink vendor is disabled because of bug #107593
136
# https://bugs.launchpad.net/bzr/+bug/107593
137
# who want plink should explicitly enable it with BZR_SSH environment
139
#~for args in (['ssh', '-V'], ['plink', '-V']):
140
for args in (['ssh', '-V'],):
141
version = self._get_ssh_version_string(args)
142
vendor = self._get_vendor_by_version_string(version, args)
143
if vendor is not None:
151
147
def get_vendor(self, environment=None):
152
148
"""Find out what version of SSH is on the system.
173
169
register_ssh_vendor = _ssh_vendor_manager.register_vendor
176
def _ignore_signals():
172
def _ignore_sigint():
177
173
# TODO: This should possibly ignore SIGHUP as well, but bzr currently
178
174
# doesn't handle it itself.
179
175
# <https://launchpad.net/products/bzr/+bug/41433/+index>
181
177
signal.signal(signal.SIGINT, signal.SIG_IGN)
182
# GZ 2010-02-19: Perhaps make this check if breakin is installed instead
183
if signal.getsignal(signal.SIGQUIT) != signal.SIG_DFL:
184
signal.signal(signal.SIGQUIT, signal.SIG_IGN)
187
class SocketAsChannelAdapter(object):
180
class LoopbackSFTP(object):
188
181
"""Simple wrapper for a socket that pretends to be a paramiko Channel."""
190
183
def __init__(self, sock):
191
184
self.__socket = sock
194
return "bzr SocketAsChannelAdapter"
196
186
def send(self, data):
197
187
return self.__socket.send(data)
199
189
def recv(self, n):
201
return self.__socket.recv(n)
202
except socket.error, e:
203
if e.args[0] in (errno.EPIPE, errno.ECONNRESET, errno.ECONNABORTED,
205
# Connection has closed. Paramiko expects an empty string in
206
# this case, not an exception.
190
return self.__socket.recv(n)
210
192
def recv_ready(self):
211
# TODO: jam 20051215 this function is necessary to support the
212
# pipelined() function. In reality, it probably should use
213
# poll() or select() to actually return if there is data
214
# available, otherwise we probably don't get any benefit
224
202
def connect_sftp(self, username, password, host, port):
225
203
"""Make an SSH connection, and return an SFTPClient.
227
205
:param username: an ascii string
228
206
:param password: an ascii string
229
207
:param host: a host name as an ascii string
239
217
def connect_ssh(self, username, password, host, port, command):
240
218
"""Make an SSH connection.
242
220
:returns: something with a `close` method, and a `get_filelike_channels`
243
221
method that returns a pair of (read, write) filelike objects.
264
242
sock.connect((host, port))
265
243
except socket.error, e:
266
244
self._raise_connection_error(host, port=port, orig_error=e)
267
return SFTPClient(SocketAsChannelAdapter(sock))
245
return SFTPClient(LoopbackSFTP(sock))
269
247
register_ssh_vendor('loopback', LoopbackVendor())
353
331
register_ssh_vendor('paramiko', vendor)
354
332
register_ssh_vendor('none', vendor)
355
333
register_default_ssh_vendor(vendor)
356
_sftp_connection_errors = (EOFError, paramiko.SSHException)
359
_sftp_connection_errors = (EOFError,)
362
337
class SubprocessVendor(SSHVendor):
374
349
argv = self._get_vendor_specific_argv(username, host, port,
375
350
subsystem='sftp')
376
351
sock = self._connect(argv)
377
return SFTPClient(SocketAsChannelAdapter(sock))
378
except _sftp_connection_errors, e:
352
return SFTPClient(sock)
353
except (EOFError, paramiko.SSHException), e:
379
354
self._raise_connection_error(host, port=port, orig_error=e)
380
355
except (OSError, IOError), e:
381
356
# If the machine is fast enough, ssh can actually exit
403
378
def _get_vendor_specific_argv(self, username, host, port, subsystem=None,
405
380
"""Returns the argument list to run the subprocess with.
407
382
Exactly one of 'subsystem' and 'command' must be specified.
409
384
raise NotImplementedError(self._get_vendor_specific_argv)
412
387
class OpenSSHSubprocessVendor(SubprocessVendor):
413
388
"""SSH vendor that uses the 'ssh' executable from OpenSSH."""
415
executable_path = 'ssh'
417
390
def _get_vendor_specific_argv(self, username, host, port, subsystem=None,
419
args = [self.executable_path,
392
assert subsystem is not None or command is not None, (
393
'Must specify a command or subsystem')
394
if subsystem is not None:
395
assert command is None, (
396
'subsystem and command are mutually exclusive')
420
398
'-oForwardX11=no', '-oForwardAgent=no',
421
399
'-oClearAllForwardings=yes', '-oProtocol=2',
422
400
'-oNoHostAuthenticationForLocalhost=yes']
436
414
class SSHCorpSubprocessVendor(SubprocessVendor):
437
415
"""SSH vendor that uses the 'ssh' executable from SSH Corporation."""
439
executable_path = 'ssh'
441
417
def _get_vendor_specific_argv(self, username, host, port, subsystem=None,
443
args = [self.executable_path, '-x']
419
assert subsystem is not None or command is not None, (
420
'Must specify a command or subsystem')
421
if subsystem is not None:
422
assert command is None, (
423
'subsystem and command are mutually exclusive')
444
425
if port is not None:
445
426
args.extend(['-p', str(port)])
446
427
if username is not None:
451
432
args.extend([host] + command)
454
register_ssh_vendor('sshcorp', SSHCorpSubprocessVendor())
435
register_ssh_vendor('ssh', SSHCorpSubprocessVendor())
457
438
class PLinkSubprocessVendor(SubprocessVendor):
458
439
"""SSH vendor that uses the 'plink' executable from Putty."""
460
executable_path = 'plink'
462
441
def _get_vendor_specific_argv(self, username, host, port, subsystem=None,
464
args = [self.executable_path, '-x', '-a', '-ssh', '-2', '-batch']
443
assert subsystem is not None or command is not None, (
444
'Must specify a command or subsystem')
445
if subsystem is not None:
446
assert command is None, (
447
'subsystem and command are mutually exclusive')
448
args = ['plink', '-x', '-a', '-ssh', '-2']
465
449
if port is not None:
466
450
args.extend(['-P', str(port)])
467
451
if username is not None:
478
462
def _paramiko_auth(username, password, host, port, paramiko_transport):
463
# paramiko requires a username, but it might be none if nothing was supplied
464
# use the local username, just in case.
465
# We don't override username, because if we aren't using paramiko,
466
# the username might be specified in ~/.ssh/config and we don't want to
467
# force it to something else
468
# Also, it would mess up the self.relpath() functionality
479
469
auth = config.AuthenticationConfig()
480
# paramiko requires a username, but it might be none if nothing was
481
# supplied. If so, use the local username.
482
470
if username is None:
483
username = auth.get_user('ssh', host, port=port,
484
default=getpass.getuser())
471
username = auth.get_user('ssh', host, port=port)
473
# Default to local user
474
username = getpass.getuser()
485
476
if _use_ssh_agent:
486
477
agent = paramiko.Agent()
487
478
for key in agent.get_keys():
499
490
if _try_pkey_auth(paramiko_transport, paramiko.DSSKey, username, 'id_dsa'):
502
# If we have gotten this far, we are about to try for passwords, do an
503
# auth_none check to see if it is even supported.
504
supported_auth_types = []
506
# Note that with paramiko <1.7.5 this logs an INFO message:
507
# Authentication type (none) not permitted.
508
# So we explicitly disable the logging level for this action
509
old_level = paramiko_transport.logger.level
510
paramiko_transport.logger.setLevel(logging.WARNING)
512
paramiko_transport.auth_none(username)
514
paramiko_transport.logger.setLevel(old_level)
515
except paramiko.BadAuthenticationType, e:
516
# Supported methods are in the exception
517
supported_auth_types = e.allowed_types
518
except paramiko.SSHException, e:
519
# Don't know what happened, but just ignore it
521
# We treat 'keyboard-interactive' and 'password' auth methods identically,
522
# because Paramiko's auth_password method will automatically try
523
# 'keyboard-interactive' auth (using the password as the response) if
524
# 'password' auth is not available. Apparently some Debian and Gentoo
525
# OpenSSH servers require this.
526
# XXX: It's possible for a server to require keyboard-interactive auth that
527
# requires something other than a single password, but we currently don't
529
if ('password' not in supported_auth_types and
530
'keyboard-interactive' not in supported_auth_types):
531
raise errors.ConnectionError('Unable to authenticate to SSH host as'
532
'\n %s@%s\nsupported auth types: %s'
533
% (username, host, supported_auth_types))
537
495
paramiko_transport.auth_password(username, password)
542
500
# give up and ask for a password
543
501
password = auth.get_password('ssh', host, username, port=port)
544
# get_password can still return None, which means we should not prompt
545
if password is not None:
547
paramiko_transport.auth_password(username, password)
548
except paramiko.SSHException, e:
549
raise errors.ConnectionError(
550
'Unable to authenticate to SSH host as'
551
'\n %s@%s\n' % (username, host), e)
553
raise errors.ConnectionError('Unable to authenticate to SSH host as'
554
' %s@%s' % (username, host))
503
paramiko_transport.auth_password(username, password)
504
except paramiko.SSHException, e:
505
raise errors.ConnectionError(
506
'Unable to authenticate to SSH host as %s@%s' % (username, host), e)
557
509
def _try_pkey_auth(paramiko_transport, pkey_class, username, filename):
619
571
def os_specific_subprocess_params():
620
572
"""Get O/S specific subprocess parameters."""
621
573
if sys.platform == 'win32':
622
# setting the process group and closing fds is not supported on
574
# setting the process group and closing fds is not supported on
626
# We close fds other than the pipes as the child process does not need
578
# We close fds other than the pipes as the child process does not need
627
579
# them to be open.
629
581
# We also set the child process to ignore SIGINT. Normally the signal
631
583
# this causes it to be seen only by bzr and not by ssh. Python will
632
584
# generate a KeyboardInterrupt in bzr, and we will then have a chance
633
585
# to release locks or do other cleanup over ssh before the connection
635
587
# <https://launchpad.net/products/bzr/+bug/5987>
637
589
# Running it in a separate process group is not good because then it
638
590
# can't get non-echoed input of a password or passphrase.
639
591
# <https://launchpad.net/products/bzr/+bug/40508>
640
return {'preexec_fn': _ignore_signals,
592
return {'preexec_fn': _ignore_sigint,
641
593
'close_fds': True,
645
_subproc_weakrefs = set()
647
def _close_ssh_proc(proc):
648
for func in [proc.stdin.close, proc.stdout.close, proc.wait]:
655
597
class SSHSubprocess(object):
656
598
"""A socket-like object that talks to an ssh subprocess via pipes."""
658
600
def __init__(self, proc):
660
# Add a weakref to proc that will attempt to do the same as self.close
661
# to avoid leaving processes lingering indefinitely.
663
_subproc_weakrefs.remove(ref)
664
_close_ssh_proc(proc)
665
_subproc_weakrefs.add(weakref.ref(self, terminate))
667
603
def send(self, data):
668
604
return os.write(self.proc.stdin.fileno(), data)
606
def recv_ready(self):
607
# TODO: jam 20051215 this function is necessary to support the
608
# pipelined() function. In reality, it probably should use
609
# poll() or select() to actually return if there is data
610
# available, otherwise we probably don't get any benefit
670
613
def recv(self, count):
671
614
return os.read(self.proc.stdout.fileno(), count)
674
_close_ssh_proc(self.proc)
617
self.proc.stdin.close()
618
self.proc.stdout.close()
676
621
def get_filelike_channels(self):
677
622
return (self.proc.stdout, self.proc.stdin)