1
# Copyright (C) 2005 Robey Pointer <robey@lag.net>
2
# Copyright (C) 2005, 2006, 2007 Canonical Ltd
4
# This program is free software; you can redistribute it and/or modify
5
# it under the terms of the GNU General Public License as published by
6
# the Free Software Foundation; either version 2 of the License, or
7
# (at your option) any later version.
9
# This program is distributed in the hope that it will be useful,
10
# but WITHOUT ANY WARRANTY; without even the implied warranty of
11
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12
# GNU General Public License for more details.
14
# You should have received a copy of the GNU General Public License
15
# along with this program; if not, write to the Free Software
16
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18
"""Foundation SSH support for SFTP and smart server."""
37
except ImportError, e:
38
# If we have an ssh subprocess, we don't strictly need paramiko for all ssh
42
from paramiko.sftp_client import SFTPClient
49
_paramiko_version = getattr(paramiko, '__version_info__', (0, 0, 0))
51
# Paramiko 1.5 tries to open a socket.AF_UNIX in order to connect
52
# to ssh-agent. That attribute doesn't exist on win32 (it does in cygwin)
53
# so we get an AttributeError exception. So we will not try to
54
# connect to an agent if we are on win32 and using Paramiko older than 1.6
55
_use_ssh_agent = (sys.platform != 'win32' or _paramiko_version >= (1, 6, 0))
58
class SSHVendorManager(object):
59
"""Manager for manage SSH vendors."""
61
# Note, although at first sign the class interface seems similar to
62
# bzrlib.registry.Registry it is not possible/convenient to directly use
63
# the Registry because the class just has "get()" interface instead of the
64
# Registry's "get(key)".
67
self._ssh_vendors = {}
68
self._cached_ssh_vendor = None
69
self._default_ssh_vendor = None
71
def register_default_vendor(self, vendor):
72
"""Register default SSH vendor."""
73
self._default_ssh_vendor = vendor
75
def register_vendor(self, name, vendor):
76
"""Register new SSH vendor by name."""
77
self._ssh_vendors[name] = vendor
79
def clear_cache(self):
80
"""Clear previously cached lookup result."""
81
self._cached_ssh_vendor = None
83
def _get_vendor_by_environment(self, environment=None):
84
"""Return the vendor or None based on BZR_SSH environment variable.
86
:raises UnknownSSH: if the BZR_SSH environment variable contains
89
if environment is None:
90
environment = os.environ
91
if 'BZR_SSH' in environment:
92
vendor_name = environment['BZR_SSH']
94
vendor = self._ssh_vendors[vendor_name]
96
raise errors.UnknownSSH(vendor_name)
100
def _get_ssh_version_string(self, args):
101
"""Return SSH version string from the subprocess."""
103
p = subprocess.Popen(args,
104
stdout=subprocess.PIPE,
105
stderr=subprocess.PIPE,
106
**os_specific_subprocess_params())
107
stdout, stderr = p.communicate()
110
return stdout + stderr
112
def _get_vendor_by_version_string(self, version, args):
113
"""Return the vendor or None based on output from the subprocess.
115
:param version: The output of 'ssh -V' like command.
116
:param args: Command line that was run.
119
if 'OpenSSH' in version:
120
trace.mutter('ssh implementation is OpenSSH')
121
vendor = OpenSSHSubprocessVendor()
122
elif 'SSH Secure Shell' in version:
123
trace.mutter('ssh implementation is SSH Corp.')
124
vendor = SSHCorpSubprocessVendor()
125
elif 'plink' in version and args[0] == 'plink':
126
# Checking if "plink" was the executed argument as Windows
127
# sometimes reports 'ssh -V' incorrectly with 'plink' in it's
128
# version. See https://bugs.launchpad.net/bzr/+bug/107155
129
trace.mutter("ssh implementation is Putty's plink.")
130
vendor = PLinkSubprocessVendor()
133
def _get_vendor_by_inspection(self):
134
"""Return the vendor or None by checking for known SSH implementations."""
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:
147
def get_vendor(self, environment=None):
148
"""Find out what version of SSH is on the system.
150
:raises SSHVendorNotFound: if no any SSH vendor is found
151
:raises UnknownSSH: if the BZR_SSH environment variable contains
154
if self._cached_ssh_vendor is None:
155
vendor = self._get_vendor_by_environment(environment)
157
vendor = self._get_vendor_by_inspection()
159
trace.mutter('falling back to default implementation')
160
vendor = self._default_ssh_vendor
162
raise errors.SSHVendorNotFound()
163
self._cached_ssh_vendor = vendor
164
return self._cached_ssh_vendor
166
_ssh_vendor_manager = SSHVendorManager()
167
_get_ssh_vendor = _ssh_vendor_manager.get_vendor
168
register_default_ssh_vendor = _ssh_vendor_manager.register_default_vendor
169
register_ssh_vendor = _ssh_vendor_manager.register_vendor
172
def _ignore_sigint():
173
# TODO: This should possibly ignore SIGHUP as well, but bzr currently
174
# doesn't handle it itself.
175
# <https://launchpad.net/products/bzr/+bug/41433/+index>
177
signal.signal(signal.SIGINT, signal.SIG_IGN)
180
class LoopbackSFTP(object):
181
"""Simple wrapper for a socket that pretends to be a paramiko Channel."""
183
def __init__(self, sock):
186
def send(self, data):
187
return self.__socket.send(data)
190
return self.__socket.recv(n)
192
def recv_ready(self):
196
self.__socket.close()
199
class SSHVendor(object):
200
"""Abstract base class for SSH vendor implementations."""
202
def connect_sftp(self, username, password, host, port):
203
"""Make an SSH connection, and return an SFTPClient.
205
:param username: an ascii string
206
:param password: an ascii string
207
:param host: a host name as an ascii string
208
:param port: a port number
211
:raises: ConnectionError if it cannot connect.
213
:rtype: paramiko.sftp_client.SFTPClient
215
raise NotImplementedError(self.connect_sftp)
217
def connect_ssh(self, username, password, host, port, command):
218
"""Make an SSH connection.
220
:returns: something with a `close` method, and a `get_filelike_channels`
221
method that returns a pair of (read, write) filelike objects.
223
raise NotImplementedError(self.connect_ssh)
225
def _raise_connection_error(self, host, port=None, orig_error=None,
226
msg='Unable to connect to SSH host'):
227
"""Raise a SocketConnectionError with properly formatted host.
229
This just unifies all the locations that try to raise ConnectionError,
230
so that they format things properly.
232
raise errors.SocketConnectionError(host=host, port=port, msg=msg,
233
orig_error=orig_error)
236
class LoopbackVendor(SSHVendor):
237
"""SSH "vendor" that connects over a plain TCP socket, not SSH."""
239
def connect_sftp(self, username, password, host, port):
240
sock = socket.socket()
242
sock.connect((host, port))
243
except socket.error, e:
244
self._raise_connection_error(host, port=port, orig_error=e)
245
return SFTPClient(LoopbackSFTP(sock))
247
register_ssh_vendor('loopback', LoopbackVendor())
250
class _ParamikoSSHConnection(object):
251
def __init__(self, channel):
252
self.channel = channel
254
def get_filelike_channels(self):
255
return self.channel.makefile('rb'), self.channel.makefile('wb')
258
return self.channel.close()
261
class ParamikoVendor(SSHVendor):
262
"""Vendor that uses paramiko."""
264
def _connect(self, username, password, host, port):
265
global SYSTEM_HOSTKEYS, BZR_HOSTKEYS
270
t = paramiko.Transport((host, port or 22))
271
t.set_log_channel('bzr.paramiko')
273
except (paramiko.SSHException, socket.error), e:
274
self._raise_connection_error(host, port=port, orig_error=e)
276
server_key = t.get_remote_server_key()
277
server_key_hex = paramiko.util.hexify(server_key.get_fingerprint())
278
keytype = server_key.get_name()
279
if host in SYSTEM_HOSTKEYS and keytype in SYSTEM_HOSTKEYS[host]:
280
our_server_key = SYSTEM_HOSTKEYS[host][keytype]
281
our_server_key_hex = paramiko.util.hexify(
282
our_server_key.get_fingerprint())
283
elif host in BZR_HOSTKEYS and keytype in BZR_HOSTKEYS[host]:
284
our_server_key = BZR_HOSTKEYS[host][keytype]
285
our_server_key_hex = paramiko.util.hexify(
286
our_server_key.get_fingerprint())
288
trace.warning('Adding %s host key for %s: %s'
289
% (keytype, host, server_key_hex))
290
add = getattr(BZR_HOSTKEYS, 'add', None)
291
if add is not None: # paramiko >= 1.X.X
292
BZR_HOSTKEYS.add(host, keytype, server_key)
294
BZR_HOSTKEYS.setdefault(host, {})[keytype] = server_key
295
our_server_key = server_key
296
our_server_key_hex = paramiko.util.hexify(
297
our_server_key.get_fingerprint())
299
if server_key != our_server_key:
300
filename1 = os.path.expanduser('~/.ssh/known_hosts')
301
filename2 = osutils.pathjoin(config.config_dir(), 'ssh_host_keys')
302
raise errors.TransportError(
303
'Host keys for %s do not match! %s != %s' %
304
(host, our_server_key_hex, server_key_hex),
305
['Try editing %s or %s' % (filename1, filename2)])
307
_paramiko_auth(username, password, host, port, t)
310
def connect_sftp(self, username, password, host, port):
311
t = self._connect(username, password, host, port)
313
return t.open_sftp_client()
314
except paramiko.SSHException, e:
315
self._raise_connection_error(host, port=port, orig_error=e,
316
msg='Unable to start sftp client')
318
def connect_ssh(self, username, password, host, port, command):
319
t = self._connect(username, password, host, port)
321
channel = t.open_session()
322
cmdline = ' '.join(command)
323
channel.exec_command(cmdline)
324
return _ParamikoSSHConnection(channel)
325
except paramiko.SSHException, e:
326
self._raise_connection_error(host, port=port, orig_error=e,
327
msg='Unable to invoke remote bzr')
329
if paramiko is not None:
330
vendor = ParamikoVendor()
331
register_ssh_vendor('paramiko', vendor)
332
register_ssh_vendor('none', vendor)
333
register_default_ssh_vendor(vendor)
337
class SubprocessVendor(SSHVendor):
338
"""Abstract base class for vendors that use pipes to a subprocess."""
340
def _connect(self, argv):
341
proc = subprocess.Popen(argv,
342
stdin=subprocess.PIPE,
343
stdout=subprocess.PIPE,
344
**os_specific_subprocess_params())
345
return SSHSubprocess(proc)
347
def connect_sftp(self, username, password, host, port):
349
argv = self._get_vendor_specific_argv(username, host, port,
351
sock = self._connect(argv)
352
return SFTPClient(sock)
353
except (EOFError, paramiko.SSHException), e:
354
self._raise_connection_error(host, port=port, orig_error=e)
355
except (OSError, IOError), e:
356
# If the machine is fast enough, ssh can actually exit
357
# before we try and send it the sftp request, which
358
# raises a Broken Pipe
359
if e.errno not in (errno.EPIPE,):
361
self._raise_connection_error(host, port=port, orig_error=e)
363
def connect_ssh(self, username, password, host, port, command):
365
argv = self._get_vendor_specific_argv(username, host, port,
367
return self._connect(argv)
368
except (EOFError), e:
369
self._raise_connection_error(host, port=port, orig_error=e)
370
except (OSError, IOError), e:
371
# If the machine is fast enough, ssh can actually exit
372
# before we try and send it the sftp request, which
373
# raises a Broken Pipe
374
if e.errno not in (errno.EPIPE,):
376
self._raise_connection_error(host, port=port, orig_error=e)
378
def _get_vendor_specific_argv(self, username, host, port, subsystem=None,
380
"""Returns the argument list to run the subprocess with.
382
Exactly one of 'subsystem' and 'command' must be specified.
384
raise NotImplementedError(self._get_vendor_specific_argv)
387
class OpenSSHSubprocessVendor(SubprocessVendor):
388
"""SSH vendor that uses the 'ssh' executable from OpenSSH."""
390
def _get_vendor_specific_argv(self, username, host, port, subsystem=None,
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')
398
'-oForwardX11=no', '-oForwardAgent=no',
399
'-oClearAllForwardings=yes', '-oProtocol=2',
400
'-oNoHostAuthenticationForLocalhost=yes']
402
args.extend(['-p', str(port)])
403
if username is not None:
404
args.extend(['-l', username])
405
if subsystem is not None:
406
args.extend(['-s', host, subsystem])
408
args.extend([host] + command)
411
register_ssh_vendor('openssh', OpenSSHSubprocessVendor())
414
class SSHCorpSubprocessVendor(SubprocessVendor):
415
"""SSH vendor that uses the 'ssh' executable from SSH Corporation."""
417
def _get_vendor_specific_argv(self, username, host, port, subsystem=None,
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')
426
args.extend(['-p', str(port)])
427
if username is not None:
428
args.extend(['-l', username])
429
if subsystem is not None:
430
args.extend(['-s', subsystem, host])
432
args.extend([host] + command)
435
register_ssh_vendor('ssh', SSHCorpSubprocessVendor())
438
class PLinkSubprocessVendor(SubprocessVendor):
439
"""SSH vendor that uses the 'plink' executable from Putty."""
441
def _get_vendor_specific_argv(self, username, host, port, subsystem=None,
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']
450
args.extend(['-P', str(port)])
451
if username is not None:
452
args.extend(['-l', username])
453
if subsystem is not None:
454
args.extend(['-s', host, subsystem])
456
args.extend([host] + command)
459
register_ssh_vendor('plink', PLinkSubprocessVendor())
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
469
auth = config.AuthenticationConfig()
471
username = auth.get_user('ssh', host, port=port)
473
# Default to local user
474
username = getpass.getuser()
477
agent = paramiko.Agent()
478
for key in agent.get_keys():
479
trace.mutter('Trying SSH agent key %s'
480
% paramiko.util.hexify(key.get_fingerprint()))
482
paramiko_transport.auth_publickey(username, key)
484
except paramiko.SSHException, e:
487
# okay, try finding id_rsa or id_dss? (posix only)
488
if _try_pkey_auth(paramiko_transport, paramiko.RSAKey, username, 'id_rsa'):
490
if _try_pkey_auth(paramiko_transport, paramiko.DSSKey, username, 'id_dsa'):
495
paramiko_transport.auth_password(username, password)
497
except paramiko.SSHException, e:
500
# give up and ask for a password
501
password = auth.get_password('ssh', host, username, port=port)
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)
509
def _try_pkey_auth(paramiko_transport, pkey_class, username, filename):
510
filename = os.path.expanduser('~/.ssh/' + filename)
512
key = pkey_class.from_private_key_file(filename)
513
paramiko_transport.auth_publickey(username, key)
515
except paramiko.PasswordRequiredException:
516
password = ui.ui_factory.get_password(
517
prompt='SSH %(filename)s password', filename=filename)
519
key = pkey_class.from_private_key_file(filename, password)
520
paramiko_transport.auth_publickey(username, key)
522
except paramiko.SSHException:
523
trace.mutter('SSH authentication via %s key failed.'
524
% (os.path.basename(filename),))
525
except paramiko.SSHException:
526
trace.mutter('SSH authentication via %s key failed.'
527
% (os.path.basename(filename),))
533
def load_host_keys():
535
Load system host keys (probably doesn't work on windows) and any
536
"discovered" keys from previous sessions.
538
global SYSTEM_HOSTKEYS, BZR_HOSTKEYS
540
SYSTEM_HOSTKEYS = paramiko.util.load_host_keys(
541
os.path.expanduser('~/.ssh/known_hosts'))
543
trace.mutter('failed to load system host keys: ' + str(e))
544
bzr_hostkey_path = osutils.pathjoin(config.config_dir(), 'ssh_host_keys')
546
BZR_HOSTKEYS = paramiko.util.load_host_keys(bzr_hostkey_path)
548
trace.mutter('failed to load bzr host keys: ' + str(e))
552
def save_host_keys():
554
Save "discovered" host keys in $(config)/ssh_host_keys/.
556
global SYSTEM_HOSTKEYS, BZR_HOSTKEYS
557
bzr_hostkey_path = osutils.pathjoin(config.config_dir(), 'ssh_host_keys')
558
config.ensure_config_dir_exists()
561
f = open(bzr_hostkey_path, 'w')
562
f.write('# SSH host keys collected by bzr\n')
563
for hostname, keys in BZR_HOSTKEYS.iteritems():
564
for keytype, key in keys.iteritems():
565
f.write('%s %s %s\n' % (hostname, keytype, key.get_base64()))
568
trace.mutter('failed to save bzr host keys: ' + str(e))
571
def os_specific_subprocess_params():
572
"""Get O/S specific subprocess parameters."""
573
if sys.platform == 'win32':
574
# setting the process group and closing fds is not supported on
578
# We close fds other than the pipes as the child process does not need
581
# We also set the child process to ignore SIGINT. Normally the signal
582
# would be sent to every process in the foreground process group, but
583
# this causes it to be seen only by bzr and not by ssh. Python will
584
# generate a KeyboardInterrupt in bzr, and we will then have a chance
585
# to release locks or do other cleanup over ssh before the connection
587
# <https://launchpad.net/products/bzr/+bug/5987>
589
# Running it in a separate process group is not good because then it
590
# can't get non-echoed input of a password or passphrase.
591
# <https://launchpad.net/products/bzr/+bug/40508>
592
return {'preexec_fn': _ignore_sigint,
597
class SSHSubprocess(object):
598
"""A socket-like object that talks to an ssh subprocess via pipes."""
600
def __init__(self, proc):
603
def send(self, data):
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
613
def recv(self, count):
614
return os.read(self.proc.stdout.fileno(), count)
617
self.proc.stdin.close()
618
self.proc.stdout.close()
621
def get_filelike_channels(self):
622
return (self.proc.stdout, self.proc.stdin)
added
removed
bzrlib/transport/ssh.py
