diff options
| -rw-r--r-- | paramiko/_version.py | 2 | ||||
| -rw-r--r-- | paramiko/channel.py | 53 | ||||
| -rw-r--r-- | paramiko/client.py | 66 | ||||
| -rw-r--r-- | paramiko/message.py | 15 | ||||
| -rw-r--r-- | paramiko/transport.py | 17 | ||||
| -rw-r--r-- | sites/www/changelog.rst | 22 | ||||
| -rw-r--r-- | tests/test_client.py | 105 |
7 files changed, 238 insertions, 42 deletions
diff --git a/paramiko/_version.py b/paramiko/_version.py index 98c3cc2d..a6d1392b 100644 --- a/paramiko/_version.py +++ b/paramiko/_version.py @@ -1,2 +1,2 @@ -__version_info__ = (2, 0, 6) +__version_info__ = (2, 1, 3) __version__ = '.'.join(map(str, __version_info__)) diff --git a/paramiko/channel.py b/paramiko/channel.py index 1f603cf0..db2aa586 100644 --- a/paramiko/channel.py +++ b/paramiko/channel.py @@ -291,6 +291,59 @@ class Channel (ClosingContextManager): m.add_int(height_pixels) self.transport._send_user_message(m) + @open_only + def update_environment(self, environment): + """ + Updates this channel's remote shell environment. + + .. note:: + This operation is additive - i.e. the current environment is not + reset before the given environment variables are set. + + .. warning:: + Servers may silently reject some environment variables; see the + warning in `set_environment_variable` for details. + + :param dict environment: + a dictionary containing the name and respective values to set + :raises: + `.SSHException` -- if any of the environment variables was rejected + by the server or the channel was closed + """ + for name, value in environment.items(): + try: + self.set_environment_variable(name, value) + except SSHException as e: + err = "Failed to set environment variable \"{0}\"." + raise SSHException(err.format(name), e) + + @open_only + def set_environment_variable(self, name, value): + """ + Set the value of an environment variable. + + .. warning:: + The server may reject this request depending on its ``AcceptEnv`` + setting; such rejections will fail silently (which is common client + practice for this particular request type). Make sure you + understand your server's configuration before using! + + :param str name: name of the environment variable + :param str value: value of the environment variable + + :raises: + `.SSHException` -- if the request was rejected or the channel was + closed + """ + m = Message() + m.add_byte(cMSG_CHANNEL_REQUEST) + m.add_int(self.remote_chanid) + m.add_string('env') + m.add_boolean(False) + m.add_string(name) + m.add_string(value) + self.transport._send_user_message(m) + def exit_status_ready(self): """ Return true if the remote process has exited and returned an exit diff --git a/paramiko/client.py b/paramiko/client.py index 224109bf..c832c578 100644 --- a/paramiko/client.py +++ b/paramiko/client.py @@ -340,35 +340,41 @@ class SSHClient (ClosingContextManager): t.set_log_channel(self._log_channel) if banner_timeout is not None: t.banner_timeout = banner_timeout - t.start_client() - - server_key = t.get_remote_server_key() - keytype = server_key.get_name() if port == SSH_PORT: server_hostkey_name = hostname else: server_hostkey_name = "[%s]:%d" % (hostname, port) + our_server_keys = None # If GSS-API Key Exchange is performed we are not required to check the # host key, because the host is authenticated via GSS-API / SSPI as # well as our client. if not self._transport.use_gss_kex: - our_server_key = self._system_host_keys.get( - server_hostkey_name, {}).get(keytype) - if our_server_key is None: - our_server_key = self._host_keys.get(server_hostkey_name, - {}).get(keytype, None) - if our_server_key is None: - # will raise exception if the key is rejected; - # let that fall out - self._policy.missing_host_key(self, server_hostkey_name, - server_key) - # if the callback returns, assume the key is ok - our_server_key = server_key - - if server_key != our_server_key: - raise BadHostKeyException(hostname, server_key, our_server_key) + our_server_keys = self._system_host_keys.get(server_hostkey_name) + if our_server_keys is None: + our_server_keys = self._host_keys.get(server_hostkey_name) + if our_server_keys is not None: + keytype = our_server_keys.keys()[0] + sec_opts = t.get_security_options() + other_types = [x for x in sec_opts.key_types if x != keytype] + sec_opts.key_types = [keytype] + other_types + + t.start_client(timeout=timeout) + + if not self._transport.use_gss_kex: + server_key = t.get_remote_server_key() + if our_server_keys is None: + # will raise exception if the key is rejected + self._policy.missing_host_key( + self, server_hostkey_name, server_key + ) + else: + our_key = our_server_keys.get(server_key.get_name()) + if our_key != server_key: + if our_key is None: + our_key = list(our_server_keys.values())[0] + raise BadHostKeyException(hostname, server_key, our_key) if username is None: username = getpass.getuser() @@ -403,7 +409,14 @@ class SSHClient (ClosingContextManager): self._agent.close() self._agent = None - def exec_command(self, command, bufsize=-1, timeout=None, get_pty=False): + def exec_command( + self, + command, + bufsize=-1, + timeout=None, + get_pty=False, + environment=None, + ): """ Execute a command on the SSH server. A new `.Channel` is opened and the requested command is executed. The command's input and output @@ -416,6 +429,14 @@ class SSHClient (ClosingContextManager): Python :param int timeout: set command's channel timeout. See `.Channel.settimeout` + :param dict environment: + a dict of shell environment variables, to be merged into the + default environment that the remote command executes within. + + .. warning:: + Servers may silently reject some environment variables; see the + warning in `.Channel.set_environment_variable` for details. + :return: the stdin, stdout, and stderr of the executing command, as a 3-tuple @@ -426,6 +447,8 @@ class SSHClient (ClosingContextManager): if get_pty: chan.get_pty() chan.settimeout(timeout) + if environment: + chan.update_environment(environment) chan.exec_command(command) stdin = chan.makefile('wb', bufsize) stdout = chan.makefile('r', bufsize) @@ -433,7 +456,7 @@ class SSHClient (ClosingContextManager): return stdin, stdout, stderr def invoke_shell(self, term='vt100', width=80, height=24, width_pixels=0, - height_pixels=0): + height_pixels=0, environment=None): """ Start an interactive shell session on the SSH server. A new `.Channel` is opened and connected to a pseudo-terminal using the requested @@ -445,6 +468,7 @@ class SSHClient (ClosingContextManager): :param int height: the height (in characters) of the terminal window :param int width_pixels: the width (in pixels) of the terminal window :param int height_pixels: the height (in pixels) of the terminal window + :param dict environment: the command's environment :return: a new `.Channel` connected to the remote shell :raises: `.SSHException` -- if the server fails to invoke a shell diff --git a/paramiko/message.py b/paramiko/message.py index 02af2526..f8ed6170 100644 --- a/paramiko/message.py +++ b/paramiko/message.py @@ -144,9 +144,6 @@ class Message (object): def get_int(self): """ Fetch an int from the stream. - - @return: a 32-bit unsigned integer. - @rtype: int """ return struct.unpack('>I', self.get_bytes(4))[0] @@ -176,23 +173,15 @@ class Message (object): def get_text(self): """ - Fetch a string from the stream. This could be a byte string and may - contain unprintable characters. (It's not unheard of for a string to - contain another byte-stream Message.) - - @return: a string. - @rtype: string + Fetch a Unicode string from the stream. """ - return u(self.get_bytes(self.get_int())) + return u(self.get_string()) def get_binary(self): """ Fetch a string from the stream. This could be a byte string and may contain unprintable characters. (It's not unheard of for a string to contain another byte-stream Message.) - - @return: a string. - @rtype: string """ return self.get_bytes(self.get_int()) diff --git a/paramiko/transport.py b/paramiko/transport.py index 19d8ee70..d26af833 100644 --- a/paramiko/transport.py +++ b/paramiko/transport.py @@ -1,4 +1,5 @@ # Copyright (C) 2003-2007 Robey Pointer <robeypointer@gmail.com> +# Copyright (C) 2003-2007 Robey Pointer <robeypointer@gmail.com> # # This file is part of paramiko. # @@ -443,7 +444,7 @@ class Transport(threading.Thread, ClosingContextManager): # We need the FQDN to get this working with SSPI self.gss_host = socket.getfqdn(gss_host) - def start_client(self, event=None): + def start_client(self, event=None, timeout=None): """ Negotiate a new SSH2 session as a client. This is the first step after creating a new `.Transport`. A separate thread is created for protocol @@ -454,7 +455,7 @@ class Transport(threading.Thread, ClosingContextManager): be triggered. On failure, `is_active` will return ``False``. (Since 1.4) If ``event`` is ``None``, this method will not return until - negotation is done. On success, the method returns normally. + negotiation is done. On success, the method returns normally. Otherwise an SSHException is raised. After a successful negotiation, you will usually want to authenticate, @@ -471,6 +472,9 @@ class Transport(threading.Thread, ClosingContextManager): :param .threading.Event event: an event to trigger when negotiation is complete (optional) + :param float timeout: + a timeout, in seconds, for SSH2 session negotiation (optional) + :raises: `.SSHException` -- if negotiation fails (and no ``event`` was passed in) @@ -485,6 +489,7 @@ class Transport(threading.Thread, ClosingContextManager): # synchronous, wait for a result self.completion_event = event = threading.Event() self.start() + max_time = time.time() + timeout if timeout is not None else None while True: event.wait(0.1) if not self.active: @@ -492,7 +497,10 @@ class Transport(threading.Thread, ClosingContextManager): if e is not None: raise e raise SSHException('Negotiation failed.') - if event.is_set(): + if ( + event.is_set() or + (timeout is not None and time.time() >= max_time) + ): break def start_server(self, event=None, server=None): @@ -2080,6 +2088,9 @@ class Transport(threading.Thread, ClosingContextManager): self.host_key_type = agreed_keys[0] if self.server_mode and (self.get_server_key() is None): raise SSHException('Incompatible ssh peer (can\'t match requested host key type)') # noqa + self._log_agreement( + 'HostKey', agreed_keys[0], agreed_keys[0] + ) if self.server_mode: agreed_local_ciphers = list(filter( diff --git a/sites/www/changelog.rst b/sites/www/changelog.rst index cb3ddb67..fdf13c3a 100644 --- a/sites/www/changelog.rst +++ b/sites/www/changelog.rst @@ -2,9 +2,14 @@ Changelog ========= +* :release:`2.1.3 <2017-06-09>` * :release:`2.0.6 <2017-06-09>` * :release:`1.18.3 <2017-06-09>` * :release:`1.17.5 <2017-06-09>` +* :bug:`865` SSHClient now requests the type of host key it has (e.g. from + known_hosts) and does not consider a different type to be a "Missing" host + key. This fixes a common case where an ECDSA key is in known_hosts and the + server also has an RSA host key. Thanks to Pierce Lopez. * :support:`906 (1.18+)` Clean up a handful of outdated imports and related tweaks. Thanks to Pierce Lopez. * :bug:`984` Enhance default cipher preference order such that @@ -58,6 +63,7 @@ Changelog Pierce Lopez for assistance. * :bug:`683 (1.17+)` Make ``util.log_to_file`` append instead of replace. Thanks to ``@vlcinsky`` for the report. +* :release:`2.1.2 <2017-02-20>` * :release:`2.0.5 <2017-02-20>` * :release:`1.18.2 <2017-02-20>` * :release:`1.17.4 <2017-02-20>` @@ -86,6 +92,7 @@ Changelog test-related file we don't support, and add PyPy to Travis-CI config. Thanks to Pierce Lopez for the final patch and Pedro Rodrigues for an earlier edition. +* :release:`2.1.1 <2016-12-12>` * :release:`2.0.4 <2016-12-12>` * :release:`1.18.1 <2016-12-12>` * :bug:`859 (1.18+)` (via :issue:`860`) A tweak to the original patch @@ -97,6 +104,11 @@ Changelog features (breaking `~paramiko.client.SSHClient.invoke_shell` with an ``AttributeError``.) The offending code has been stripped out of the 2.0.x line (but of course, remains in 2.1.x and above.) +* :bug:`859` (via :issue:`860`) A tweak to the original patch implementing + :issue:`398` was not fully applied, causing calls to + `~paramiko.client.SSHClient.invoke_shell` to fail with ``AttributeError``. + This has been fixed. Patch credit: Kirk Byers. +* :release:`2.1.0 <2016-12-09>` * :release:`2.0.3 <2016-12-09>` * :release:`1.18.0 <2016-12-09>` * :release:`1.17.3 <2016-12-09>` @@ -140,6 +152,16 @@ Changelog signature. Caught by ``@Score_Under``. * :bug:`681 (1.17+)` Fix a Python3-specific bug re: the handling of read buffers when using ``ProxyCommand``. Thanks to Paul Kapp for catch & patch. +* :feature:`398 (1.18+)` Add an ``environment`` dict argument to + `Client.exec_command <paramiko.client.SSHClient.exec_command>` (plus the + lower level `Channel.update_environment + <paramiko.channel.Channel.update_environment>` and + `Channel.set_environment_variable + <paramiko.channel.Channel.set_environment_variable>` methods) which + implements the ``env`` SSH message type. This means the remote shell + environment can be set without the use of ``VARNAME=value`` shell tricks, + provided the server's ``AcceptEnv`` lists the variables you need to set. + Thanks to Philip Lorenz for the pull request. * :support:`819 backported (>=1.15,<2.0)` Document how lacking ``gmp`` headers at install time can cause a significant performance hit if you build PyCrypto from source. (Most system-distributed packages already have this enabled.) diff --git a/tests/test_client.py b/tests/test_client.py index bfdf5f81..2288cf57 100644 --- a/tests/test_client.py +++ b/tests/test_client.py @@ -82,6 +82,16 @@ class NullServer (paramiko.ServerInterface): return False return True + def check_channel_env_request(self, channel, name, value): + if name == 'INVALID_ENV': + return False + + if not hasattr(channel, 'env'): + setattr(channel, 'env', {}) + + channel.env[name] = value + return True + class SSHClientTest (unittest.TestCase): @@ -108,7 +118,11 @@ class SSHClientTest (unittest.TestCase): allowed_keys = FINGERPRINTS.keys() self.socks, addr = self.sockl.accept() self.ts = paramiko.Transport(self.socks) - host_key = paramiko.RSAKey.from_private_key_file(test_path('test_rsa.key')) + keypath = test_path('test_rsa.key') + host_key = paramiko.RSAKey.from_private_key_file(keypath) + self.ts.add_server_key(host_key) + keypath = test_path('test_ecdsa_256.key') + host_key = paramiko.ECDSAKey.from_private_key_file(keypath) self.ts.add_server_key(host_key) server = NullServer(allowed_keys=allowed_keys) if delay: @@ -232,8 +246,9 @@ class SSHClientTest (unittest.TestCase): verify that SSHClient's AutoAddPolicy works. """ threading.Thread(target=self._run).start() - host_key = paramiko.RSAKey.from_private_key_file(test_path('test_rsa.key')) - public_host_key = paramiko.RSAKey(data=host_key.asbytes()) + hostname = '[%s]:%d' % (self.addr, self.port) + key_file = test_path('test_ecdsa_256.key') + public_host_key = paramiko.ECDSAKey.from_private_key_file(key_file) self.tc = paramiko.SSHClient() self.tc.set_missing_host_key_policy(paramiko.AutoAddPolicy()) @@ -246,7 +261,8 @@ class SSHClientTest (unittest.TestCase): self.assertEqual('slowdive', self.ts.get_username()) self.assertEqual(True, self.ts.is_authenticated()) self.assertEqual(1, len(self.tc.get_host_keys())) - self.assertEqual(public_host_key, self.tc.get_host_keys()['[%s]:%d' % (self.addr, self.port)]['ssh-rsa']) + new_host_key = list(self.tc.get_host_keys()[hostname].values())[0] + self.assertEqual(public_host_key, new_host_key) def test_5_save_host_keys(self): """ @@ -366,3 +382,84 @@ class SSHClientTest (unittest.TestCase): password='pygmalion', ) self._test_connection(**kwargs) + + def _client_host_key_bad(self, host_key): + threading.Thread(target=self._run).start() + hostname = '[%s]:%d' % (self.addr, self.port) + + self.tc = paramiko.SSHClient() + self.tc.set_missing_host_key_policy(paramiko.WarningPolicy()) + known_hosts = self.tc.get_host_keys() + known_hosts.add(hostname, host_key.get_name(), host_key) + + self.assertRaises( + paramiko.BadHostKeyException, + self.tc.connect, + password='pygmalion', + **self.connect_kwargs + ) + + def _client_host_key_good(self, ktype, kfile): + threading.Thread(target=self._run).start() + hostname = '[%s]:%d' % (self.addr, self.port) + + self.tc = paramiko.SSHClient() + self.tc.set_missing_host_key_policy(paramiko.RejectPolicy()) + host_key = ktype.from_private_key_file(test_path(kfile)) + known_hosts = self.tc.get_host_keys() + known_hosts.add(hostname, host_key.get_name(), host_key) + + self.tc.connect(password='pygmalion', **self.connect_kwargs) + self.event.wait(1.0) + self.assertTrue(self.event.is_set()) + self.assertTrue(self.ts.is_active()) + self.assertEqual(True, self.ts.is_authenticated()) + + def test_host_key_negotiation_1(self): + host_key = paramiko.ECDSAKey.generate() + self._client_host_key_bad(host_key) + + def test_host_key_negotiation_2(self): + host_key = paramiko.RSAKey.generate(2048) + self._client_host_key_bad(host_key) + + def test_host_key_negotiation_3(self): + self._client_host_key_good(paramiko.ECDSAKey, 'test_ecdsa_256.key') + + def test_host_key_negotiation_4(self): + self._client_host_key_good(paramiko.RSAKey, 'test_rsa.key') + + def test_update_environment(self): + """ + Verify that environment variables can be set by the client. + """ + threading.Thread(target=self._run).start() + + self.tc = paramiko.SSHClient() + self.tc.set_missing_host_key_policy(paramiko.AutoAddPolicy()) + self.assertEqual(0, len(self.tc.get_host_keys())) + self.tc.connect(self.addr, self.port, username='slowdive', password='pygmalion') + + self.event.wait(1.0) + self.assertTrue(self.event.isSet()) + self.assertTrue(self.ts.is_active()) + + target_env = {b'A': b'B', b'C': b'd'} + + self.tc.exec_command('yes', environment=target_env) + schan = self.ts.accept(1.0) + self.assertEqual(target_env, getattr(schan, 'env', {})) + schan.close() + + # Cannot use assertRaises in context manager mode as it is not supported + # in Python 2.6. + try: + # Verify that a rejection by the server can be detected + self.tc.exec_command('yes', environment={b'INVALID_ENV': b''}) + except SSHException as e: + self.assertTrue('INVALID_ENV' in str(e), + 'Expected variable name in error message') + self.assertTrue(isinstance(e.args[1], SSHException), + 'Expected original SSHException in exception') + else: + self.assertFalse(False, 'SSHException was not thrown.') |