class TransportTest(ParamikoTest):
def setUp(self):
self.socks = LoopSocket()
self.sockc = LoopSocket()
self.sockc.link(self.socks)
self.tc = Transport(self.sockc)
self.ts = Transport(self.socks)
def tearDown(self):
self.tc.close()
self.ts.close()
self.socks.close()
self.sockc.close()
def setup_test_server(self, client_options=None, server_options=None):
host_key = RSAKey.from_private_key_file('tests/test_rsa.key')
public_host_key = RSAKey(data=bytes(host_key))
self.ts.add_server_key(host_key)
if client_options is not None:
client_options(self.tc.get_security_options())
if server_options is not None:
server_options(self.ts.get_security_options())
event = threading.Event()
self.server = NullServer()
self.assert_(not event.isSet())
self.ts.start_server(event, self.server)
self.tc.connect(hostkey=public_host_key,
username='******', password='******')
event.wait(1.0)
self.assert_(event.isSet())
self.assert_(self.ts.is_active())
def test_1_security_options(self):
o = self.tc.get_security_options()
self.assertEquals(type(o), SecurityOptions)
self.assert_((b'aes256-cbc', b'blowfish-cbc') != o.ciphers)
o.ciphers = (b'aes256-cbc', b'blowfish-cbc')
self.assertEquals((b'aes256-cbc', b'blowfish-cbc'), o.ciphers)
try:
o.ciphers = (b'aes256-cbc', b'made-up-cipher')
self.assert_(False)
except ValueError:
pass
try:
o.ciphers = 23
self.assert_(False)
except TypeError:
pass
def test_2_compute_key(self):
self.tc.K = 123281095979686581523377256114209720774539068973101330872763622971399429481072519713536292772709507296759612401802191955568143056534122385270077606457721553469730659233569339356140085284052436697480759510519672848743794433460113118986816826624865291116513647975790797391795651716378444844877749505443714557929
self.tc.H = unhexlify(b'0C8307CDE6856FF30BA93684EB0F04C2520E9ED3')
self.tc.session_id = self.tc.H
key = self.tc._compute_key(b'C', 32)
self.assertEquals(b'207E66594CA87C44ECCBA3B3CD39FDDB378E6FDB0F97C54B2AA0CFBF900CD995',
hexlify(key).upper())
def test_3_simple(self):
"""
verify that we can establish an ssh link with ourselves across the
loopback sockets. this is hardly "simple" but it's simpler than the
later tests. :)
"""
host_key = RSAKey.from_private_key_file('tests/test_rsa.key')
public_host_key = RSAKey(data=bytes(host_key))
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assert_(not event.isSet())
self.assertEquals(None, self.tc.get_username())
self.assertEquals(None, self.ts.get_username())
self.assertEquals(False, self.tc.is_authenticated())
self.assertEquals(False, self.ts.is_authenticated())
self.ts.start_server(event, server)
self.tc.connect(hostkey=public_host_key,
username='******', password='******')
event.wait(1.0)
self.assert_(event.isSet())
self.assert_(self.ts.is_active())
self.assertEquals('slowdive', self.tc.get_username())
self.assertEquals('slowdive', self.ts.get_username())
self.assertEquals(True, self.tc.is_authenticated())
self.assertEquals(True, self.ts.is_authenticated())
def test_3a_long_banner(self):
"""
verify that a long banner doesn't mess up the handshake.
"""
host_key = RSAKey.from_private_key_file('tests/test_rsa.key')
public_host_key = RSAKey(data=bytes(host_key))
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assert_(not event.isSet())
self.socks.send(LONG_BANNER)
self.ts.start_server(event, server)
self.tc.connect(hostkey=public_host_key,
username='******', password='******')
event.wait(1.0)
self.assert_(event.isSet())
self.assert_(self.ts.is_active())
def test_4_special(self):
"""
verify that the client can demand odd handshake settings, and can
renegotiate keys in mid-stream.
"""
def force_algorithms(options):
options.ciphers = (b'aes256-cbc',)
options.digests = (b'hmac-md5-96',)
self.setup_test_server(client_options=force_algorithms)
self.assertEquals(b'aes256-cbc', self.tc.local_cipher)
self.assertEquals(b'aes256-cbc', self.tc.remote_cipher)
self.assertEquals(12, self.tc.packetizer.get_mac_size_out())
self.assertEquals(12, self.tc.packetizer.get_mac_size_in())
self.tc.send_ignore(1024)
self.tc.renegotiate_keys()
self.ts.send_ignore(1024)
def test_5_keepalive(self):
"""
verify that the keepalive will be sent.
"""
self.setup_test_server()
self.assertEquals(None, getattr(self.server, '_global_request', None))
self.tc.set_keepalive(1)
time.sleep(2)
self.assertEquals(b'*****@*****.**', self.server._global_request)
def test_6_exec_command(self):
"""
verify that exec_command() does something reasonable.
"""
self.setup_test_server()
chan = self.tc.open_session()
schan = self.ts.accept(1.0)
try:
chan.exec_command('no')
self.assert_(False)
except SSHException as x:
pass
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
schan.send(b'Hello there.\n')
schan.send_stderr(b'This is on stderr.\n')
schan.close()
f = chan.makefile()
self.assertEquals(b'Hello there.\n', f.readline())
self.assertEquals(b'', f.readline())
f = chan.makefile_stderr()
self.assertEquals(b'This is on stderr.\n', f.readline())
self.assertEquals(b'', f.readline())
# now try it with combined stdout/stderr
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
schan.send(b'Hello there.\n')
schan.send_stderr(b'This is on stderr.\n')
schan.close()
chan.set_combine_stderr(True)
f = chan.makefile()
self.assertEquals(b'Hello there.\n', f.readline())
self.assertEquals(b'This is on stderr.\n', f.readline())
self.assertEquals(b'', f.readline())
def test_7_invoke_shell(self):
"""
verify that invoke_shell() does something reasonable.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
chan.send(b'communist j. cat\n')
f = schan.makefile()
self.assertEquals(b'communist j. cat\n', f.readline())
chan.close()
self.assertEquals(b'', f.readline())
def test_8_channel_exception(self):
"""
verify that ChannelException is thrown for a bad open-channel request.
"""
self.setup_test_server()
try:
chan = self.tc.open_channel(b'bogus')
self.fail('expected exception')
except ChannelException as x:
self.assert_(x.code == OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED)
def test_9_exit_status(self):
"""
verify that get_exit_status() works.
"""
self.setup_test_server()
chan = self.tc.open_session()
schan = self.ts.accept(1.0)
chan.exec_command('yes')
schan.send(b'Hello there.\n')
self.assert_(not chan.exit_status_ready())
# trigger an EOF
schan.shutdown_read()
schan.shutdown_write()
schan.send_exit_status(23)
schan.close()
f = chan.makefile()
self.assertEquals(b'Hello there.\n', f.readline())
self.assertEquals(b'', f.readline())
count = 0
while not chan.exit_status_ready():
time.sleep(0.1)
count += 1
if count > 50:
raise Exception("timeout")
self.assertEquals(23, chan.recv_exit_status())
chan.close()
def test_A_select(self):
"""
verify that select() on a channel works.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
# nothing should be ready
r, w, e = select.select([chan], [], [], 0.1)
self.assertEquals([], r)
self.assertEquals([], w)
self.assertEquals([], e)
schan.send(b'hello\n')
# something should be ready now (give it 1 second to appear)
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEquals([chan], r)
self.assertEquals([], w)
self.assertEquals([], e)
self.assertEquals(b'hello\n', chan.recv(6))
# and, should be dead again now
r, w, e = select.select([chan], [], [], 0.1)
self.assertEquals([], r)
self.assertEquals([], w)
self.assertEquals([], e)
schan.close()
# detect eof?
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEquals([chan], r)
self.assertEquals([], w)
self.assertEquals([], e)
self.assertEquals(b'', chan.recv(16))
# make sure the pipe is still open for now...
p = chan._pipe
self.assertEquals(False, p._closed)
chan.close()
# ...and now is closed.
self.assertEquals(True, p._closed)
def test_B_renegotiate(self):
"""
verify that a transport can correctly renegotiate mid-stream.
"""
self.setup_test_server()
self.tc.packetizer.REKEY_BYTES = 16384
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
self.assertEquals(self.tc.H, self.tc.session_id)
for i in range(20):
chan.send(b'x' * 1024)
chan.close()
# allow a few seconds for the rekeying to complete
for i in range(50):
if self.tc.H != self.tc.session_id:
break
time.sleep(0.1)
self.assertNotEquals(self.tc.H, self.tc.session_id)
schan.close()
def test_C_compression(self):
"""
verify that zlib compression is basically working.
"""
def force_compression(o):
o.compression = (b'zlib',)
self.setup_test_server(force_compression, force_compression)
chan = self.tc.open_session()
chan.exec_command(b'yes')
schan = self.ts.accept(1.0)
bytes = self.tc.packetizer._Packetizer__sent_bytes
chan.send(b'x' * 1024)
bytes2 = self.tc.packetizer._Packetizer__sent_bytes
# tests show this is actually compressed to *52 bytes*! including packet overhead! nice!! :)
self.assert_(bytes2 - bytes < 1024)
self.assertEquals(52, bytes2 - bytes)
chan.close()
schan.close()
def test_D_x11(self):
"""
verify that an x11 port can be requested and opened.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command(b'yes')
schan = self.ts.accept(1.0)
requested = []
def handler(c, addr):
requested.append(addr)
self.tc._queue_incoming_channel(c)
self.assertEquals(None, getattr(self.server, '_x11_screen_number', None))
cookie = chan.request_x11(0, single_connection=True, handler=handler)
self.assertEquals(0, self.server._x11_screen_number)
self.assertEquals(b'MIT-MAGIC-COOKIE-1', self.server._x11_auth_protocol)
self.assertEquals(cookie, self.server._x11_auth_cookie)
self.assertEquals(True, self.server._x11_single_connection)
x11_server = self.ts.open_x11_channel(('localhost', 6093))
x11_client = self.tc.accept()
self.assertEquals('localhost', requested[0][0])
self.assertEquals(6093, requested[0][1])
x11_server.send(b'hello')
self.assertEquals(b'hello', x11_client.recv(5))
x11_server.close()
x11_client.close()
chan.close()
schan.close()
def test_E_reverse_port_forwarding(self):
"""
verify that a client can ask the server to open a reverse port for
forwarding.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
requested = []
def handler(c, origin_addr, server_addr):
requested.append(origin_addr)
requested.append(server_addr)
self.tc._queue_incoming_channel(c)
port = self.tc.request_port_forward('127.0.0.1', 0, handler)
self.assertEquals(port, self.server._listen.getsockname()[1])
cs = socket.socket()
cs.connect((b'127.0.0.1', port))
ss, _ = self.server._listen.accept()
sch = self.ts.open_forwarded_tcpip_channel(ss.getsockname(), ss.getpeername())
cch = self.tc.accept()
sch.send(b'hello')
self.assertEquals(b'hello', cch.recv(5))
sch.close()
cch.close()
ss.close()
cs.close()
# now cancel it.
self.tc.cancel_port_forward(b'127.0.0.1', port)
self.assertTrue(self.server._listen is None)
def test_F_port_forwarding(self):
"""
verify that a client can forward new connections from a locally-
forwarded port.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
# open a port on the "server" that the client will ask to forward to.
greeting_server = socket.socket()
greeting_server.bind(('127.0.0.1', 0))
greeting_server.listen(1)
greeting_port = greeting_server.getsockname()[1]
cs = self.tc.open_channel(b'direct-tcpip', ('127.0.0.1', greeting_port), ('', 9000))
sch = self.ts.accept(1.0)
cch = socket.socket()
cch.connect(self.server._tcpip_dest)
ss, _ = greeting_server.accept()
ss.send(b'Hello!\n')
ss.close()
sch.send(cch.recv(8192))
sch.close()
self.assertEquals(b'Hello!\n', cs.recv(7))
cs.close()
def test_G_stderr_select(self):
"""
verify that select() on a channel works even if only stderr is
receiving data.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
# nothing should be ready
r, w, e = select.select([chan], [], [], 0.1)
self.assertEquals([], r)
self.assertEquals([], w)
self.assertEquals([], e)
schan.send_stderr(b'hello\n')
# something should be ready now (give it 1 second to appear)
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEquals([chan], r)
self.assertEquals([], w)
self.assertEquals([], e)
self.assertEquals(b'hello\n', chan.recv_stderr(6))
# and, should be dead again now
r, w, e = select.select([chan], [], [], 0.1)
self.assertEquals([], r)
self.assertEquals([], w)
self.assertEquals([], e)
schan.close()
chan.close()
def test_H_send_ready(self):
"""
verify that send_ready() indicates when a send would not block.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
self.assertEquals(chan.send_ready(), True)
total = 0
K = b'*' * 1024
while total < 1024 * 1024:
chan.send(K)
total += len(K)
if not chan.send_ready():
break
self.assert_(total < 1024 * 1024)
schan.close()
chan.close()
self.assertEquals(chan.send_ready(), True)
def test_I_rekey_deadlock(self):
"""
Regression test for deadlock when in-transit messages are received after MSG_KEXINIT is sent
Note: When this test fails, it may leak threads.
"""
# Test for an obscure deadlocking bug that can occur if we receive
# certain messages while initiating a key exchange.
#
# The deadlock occurs as follows:
#
# In the main thread:
# 1. The user's program calls Channel.send(), which sends
# MSG_CHANNEL_DATA to the remote host.
# 2. Packetizer discovers that REKEY_BYTES has been exceeded, and
# sets the __need_rekey flag.
#
# In the Transport thread:
# 3. Packetizer notices that the __need_rekey flag is set, and raises
# NeedRekeyException.
# 4. In response to NeedRekeyException, the transport thread sends
# MSG_KEXINIT to the remote host.
#
# On the remote host (using any SSH implementation):
# 5. The MSG_CHANNEL_DATA is received, and MSG_CHANNEL_WINDOW_ADJUST is sent.
# 6. The MSG_KEXINIT is received, and a corresponding MSG_KEXINIT is sent.
#
# In the main thread:
# 7. The user's program calls Channel.send().
# 8. Channel.send acquires Channel.lock, then calls Transport._send_user_message().
# 9. Transport._send_user_message waits for Transport.clear_to_send
# to be set (i.e., it waits for re-keying to complete).
# Channel.lock is still held.
#
# In the Transport thread:
# 10. MSG_CHANNEL_WINDOW_ADJUST is received; Channel._window_adjust
# is called to handle it.
# 11. Channel._window_adjust tries to acquire Channel.lock, but it
# blocks because the lock is already held by the main thread.
#
# The result is that the Transport thread never processes the remote
# host's MSG_KEXINIT packet, because it becomes deadlocked while
# handling the preceding MSG_CHANNEL_WINDOW_ADJUST message.
# We set up two separate threads for sending and receiving packets,
# while the main thread acts as a watchdog timer. If the timer
# expires, a deadlock is assumed.
class SendThread(threading.Thread):
def __init__(self, chan, iterations, done_event):
threading.Thread.__init__(self, None, None, self.__class__.__name__)
self.setDaemon(True)
self.chan = chan
self.iterations = iterations
self.done_event = done_event
self.watchdog_event = threading.Event()
self.last = None
def run(self):
try:
for i in range(1, 1+self.iterations):
if self.done_event.isSet():
break
self.watchdog_event.set()
#print i, "SEND"
self.chan.send(b"x" * 2048)
finally:
self.done_event.set()
self.watchdog_event.set()
class ReceiveThread(threading.Thread):
def __init__(self, chan, done_event):
threading.Thread.__init__(self, None, None, self.__class__.__name__)
self.setDaemon(True)
self.chan = chan
self.done_event = done_event
self.watchdog_event = threading.Event()
def run(self):
try:
while not self.done_event.isSet():
if self.chan.recv_ready():
chan.recv(65536)
self.watchdog_event.set()
else:
if random.randint(0, 1):
time.sleep(random.randint(0, 500) / 1000.0)
finally:
self.done_event.set()
self.watchdog_event.set()
self.setup_test_server()
self.ts.packetizer.REKEY_BYTES = 2048
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
# Monkey patch the client's Transport._handler_table so that the client
# sends MSG_CHANNEL_WINDOW_ADJUST whenever it receives an initial
# MSG_KEXINIT. This is used to simulate the effect of network latency
# on a real MSG_CHANNEL_WINDOW_ADJUST message.
self.tc._handler_table = self.tc._handler_table.copy() # copy per-class dictionary
_negotiate_keys = self.tc._handler_table[MSG_KEXINIT]
def _negotiate_keys_wrapper(self, m):
if self.local_kex_init is None: # Remote side sent KEXINIT
# Simulate in-transit MSG_CHANNEL_WINDOW_ADJUST by sending it
# before responding to the incoming MSG_KEXINIT.
m2 = Message()
m2.add_byte(chr(MSG_CHANNEL_WINDOW_ADJUST).encode())
m2.add_int(chan.remote_chanid)
m2.add_int(1) # bytes to add
self._send_message(m2)
return _negotiate_keys(self, m)
self.tc._handler_table[MSG_KEXINIT] = _negotiate_keys_wrapper
# Parameters for the test
iterations = 500 # The deadlock does not happen every time, but it
# should after many iterations.
timeout = 5
# This event is set when the test is completed
done_event = threading.Event()
# Start the sending thread
st = SendThread(schan, iterations, done_event)
st.start()
# Start the receiving thread
rt = ReceiveThread(chan, done_event)
rt.start()
# Act as a watchdog timer, checking
deadlocked = False
while not deadlocked and not done_event.isSet():
for event in (st.watchdog_event, rt.watchdog_event):
event.wait(timeout)
if done_event.isSet():
break
if not event.isSet():
deadlocked = True
break
event.clear()
# Tell the threads to stop (if they haven't already stopped). Note
# that if one or more threads are deadlocked, they might hang around
# forever (until the process exits).
done_event.set()
# Assertion: We must not have detected a timeout.
self.assertFalse(deadlocked)
# Close the channels
schan.close()
chan.close()
class TransportTest(unittest.TestCase):
def setUp(self):
self.socks = LoopSocket()
self.sockc = LoopSocket()
self.sockc.link(self.socks)
self.tc = Transport(self.sockc)
self.ts = Transport(self.socks)
def tearDown(self):
self.tc.close()
self.ts.close()
self.socks.close()
self.sockc.close()
def setup_test_server(self, client_options=None, server_options=None):
host_key = RSAKey.from_private_key_file(test_path('test_rsa.key'))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
if client_options is not None:
client_options(self.tc.get_security_options())
if server_options is not None:
server_options(self.ts.get_security_options())
event = threading.Event()
self.server = NullServer()
self.assertTrue(not event.is_set())
self.ts.start_server(event, self.server)
self.tc.connect(hostkey=public_host_key,
username='******',
password='******')
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
def test_1_security_options(self):
o = self.tc.get_security_options()
self.assertEqual(type(o), SecurityOptions)
self.assertTrue(('aes256-cbc', 'blowfish-cbc') != o.ciphers)
o.ciphers = ('aes256-cbc', 'blowfish-cbc')
self.assertEqual(('aes256-cbc', 'blowfish-cbc'), o.ciphers)
try:
o.ciphers = ('aes256-cbc', 'made-up-cipher')
self.assertTrue(False)
except ValueError:
pass
try:
o.ciphers = 23
self.assertTrue(False)
except TypeError:
pass
def test_2_compute_key(self):
self.tc.K = 123281095979686581523377256114209720774539068973101330872763622971399429481072519713536292772709507296759612401802191955568143056534122385270077606457721553469730659233569339356140085284052436697480759510519672848743794433460113118986816826624865291116513647975790797391795651716378444844877749505443714557929
self.tc.H = b'\x0C\x83\x07\xCD\xE6\x85\x6F\xF3\x0B\xA9\x36\x84\xEB\x0F\x04\xC2\x52\x0E\x9E\xD3'
self.tc.session_id = self.tc.H
key = self.tc._compute_key('C', 32)
self.assertEqual(
b'207E66594CA87C44ECCBA3B3CD39FDDB378E6FDB0F97C54B2AA0CFBF900CD995',
hexlify(key).upper())
def test_3_simple(self):
"""
verify that we can establish an ssh link with ourselves across the
loopback sockets. this is hardly "simple" but it's simpler than the
later tests. :)
"""
host_key = RSAKey.from_private_key_file(test_path('test_rsa.key'))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.assertEqual(None, self.tc.get_username())
self.assertEqual(None, self.ts.get_username())
self.assertEqual(False, self.tc.is_authenticated())
self.assertEqual(False, self.ts.is_authenticated())
self.ts.start_server(event, server)
self.tc.connect(hostkey=public_host_key,
username='******',
password='******')
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
self.assertEqual('slowdive', self.tc.get_username())
self.assertEqual('slowdive', self.ts.get_username())
self.assertEqual(True, self.tc.is_authenticated())
self.assertEqual(True, self.ts.is_authenticated())
def test_3a_long_banner(self):
"""
verify that a long banner doesn't mess up the handshake.
"""
host_key = RSAKey.from_private_key_file(test_path('test_rsa.key'))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.socks.send(LONG_BANNER)
self.ts.start_server(event, server)
self.tc.connect(hostkey=public_host_key,
username='******',
password='******')
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
def test_4_special(self):
"""
verify that the client can demand odd handshake settings, and can
renegotiate keys in mid-stream.
"""
def force_algorithms(options):
options.ciphers = ('aes256-cbc', )
options.digests = ('hmac-md5-96', )
self.setup_test_server(client_options=force_algorithms)
self.assertEqual('aes256-cbc', self.tc.local_cipher)
self.assertEqual('aes256-cbc', self.tc.remote_cipher)
self.assertEqual(12, self.tc.packetizer.get_mac_size_out())
self.assertEqual(12, self.tc.packetizer.get_mac_size_in())
self.tc.send_ignore(1024)
self.tc.renegotiate_keys()
self.ts.send_ignore(1024)
def test_5_keepalive(self):
"""
verify that the keepalive will be sent.
"""
self.setup_test_server()
self.assertEqual(None, getattr(self.server, '_global_request', None))
self.tc.set_keepalive(1)
time.sleep(2)
self.assertEqual('*****@*****.**', self.server._global_request)
def test_6_exec_command(self):
"""
verify that exec_command() does something reasonable.
"""
self.setup_test_server()
chan = self.tc.open_session()
schan = self.ts.accept(1.0)
try:
chan.exec_command('no')
self.assertTrue(False)
except SSHException:
pass
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
schan.send('Hello there.\n')
schan.send_stderr('This is on stderr.\n')
schan.close()
f = chan.makefile()
self.assertEqual('Hello there.\n', f.readline())
self.assertEqual('', f.readline())
f = chan.makefile_stderr()
self.assertEqual('This is on stderr.\n', f.readline())
self.assertEqual('', f.readline())
# now try it with combined stdout/stderr
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
schan.send('Hello there.\n')
schan.send_stderr('This is on stderr.\n')
schan.close()
chan.set_combine_stderr(True)
f = chan.makefile()
self.assertEqual('Hello there.\n', f.readline())
self.assertEqual('This is on stderr.\n', f.readline())
self.assertEqual('', f.readline())
def test_6a_channel_can_be_used_as_context_manager(self):
"""
verify that exec_command() does something reasonable.
"""
self.setup_test_server()
with self.tc.open_session() as chan:
with self.ts.accept(1.0) as schan:
chan.exec_command('yes')
schan.send('Hello there.\n')
schan.close()
f = chan.makefile()
self.assertEqual('Hello there.\n', f.readline())
self.assertEqual('', f.readline())
def test_7_invoke_shell(self):
"""
verify that invoke_shell() does something reasonable.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
chan.send('communist j. cat\n')
f = schan.makefile()
self.assertEqual('communist j. cat\n', f.readline())
chan.close()
self.assertEqual('', f.readline())
def test_8_channel_exception(self):
"""
verify that ChannelException is thrown for a bad open-channel request.
"""
self.setup_test_server()
try:
chan = self.tc.open_channel('bogus')
self.fail('expected exception')
except ChannelException as e:
self.assertTrue(e.code == OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED)
def test_9_exit_status(self):
"""
verify that get_exit_status() works.
"""
self.setup_test_server()
chan = self.tc.open_session()
schan = self.ts.accept(1.0)
chan.exec_command('yes')
schan.send('Hello there.\n')
self.assertTrue(not chan.exit_status_ready())
# trigger an EOF
schan.shutdown_read()
schan.shutdown_write()
schan.send_exit_status(23)
schan.close()
f = chan.makefile()
self.assertEqual('Hello there.\n', f.readline())
self.assertEqual('', f.readline())
count = 0
while not chan.exit_status_ready():
time.sleep(0.1)
count += 1
if count > 50:
raise Exception("timeout")
self.assertEqual(23, chan.recv_exit_status())
chan.close()
def test_A_select(self):
"""
verify that select() on a channel works.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
# nothing should be ready
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.send('hello\n')
# something should be ready now (give it 1 second to appear)
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(b'hello\n', chan.recv(6))
# and, should be dead again now
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.close()
# detect eof?
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(bytes(), chan.recv(16))
# make sure the pipe is still open for now...
p = chan._pipe
self.assertEqual(False, p._closed)
chan.close()
# ...and now is closed.
self.assertEqual(True, p._closed)
def test_B_renegotiate(self):
"""
verify that a transport can correctly renegotiate mid-stream.
"""
self.setup_test_server()
self.tc.packetizer.REKEY_BYTES = 16384
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
self.assertEqual(self.tc.H, self.tc.session_id)
for i in range(20):
chan.send('x' * 1024)
chan.close()
# allow a few seconds for the rekeying to complete
for i in range(50):
if self.tc.H != self.tc.session_id:
break
time.sleep(0.1)
self.assertNotEqual(self.tc.H, self.tc.session_id)
schan.close()
def test_C_compression(self):
"""
verify that zlib compression is basically working.
"""
def force_compression(o):
o.compression = ('zlib', )
self.setup_test_server(force_compression, force_compression)
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
bytes = self.tc.packetizer._Packetizer__sent_bytes
chan.send('x' * 1024)
bytes2 = self.tc.packetizer._Packetizer__sent_bytes
# tests show this is actually compressed to *52 bytes*! including packet overhead! nice!! :)
self.assertTrue(bytes2 - bytes < 1024)
self.assertEqual(52, bytes2 - bytes)
chan.close()
schan.close()
def test_D_x11(self):
"""
verify that an x11 port can be requested and opened.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
requested = []
def handler(c, addr_port):
addr, port = addr_port
requested.append((addr, port))
self.tc._queue_incoming_channel(c)
self.assertEqual(None, getattr(self.server, '_x11_screen_number',
None))
cookie = chan.request_x11(0, single_connection=True, handler=handler)
self.assertEqual(0, self.server._x11_screen_number)
self.assertEqual('MIT-MAGIC-COOKIE-1', self.server._x11_auth_protocol)
self.assertEqual(cookie, self.server._x11_auth_cookie)
self.assertEqual(True, self.server._x11_single_connection)
x11_server = self.ts.open_x11_channel(('localhost', 6093))
x11_client = self.tc.accept()
self.assertEqual('localhost', requested[0][0])
self.assertEqual(6093, requested[0][1])
x11_server.send('hello')
self.assertEqual(b'hello', x11_client.recv(5))
x11_server.close()
x11_client.close()
chan.close()
schan.close()
def test_E_reverse_port_forwarding(self):
"""
verify that a client can ask the server to open a reverse port for
forwarding.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
requested = []
def handler(c, origin_addr_port, server_addr_port):
requested.append(origin_addr_port)
requested.append(server_addr_port)
self.tc._queue_incoming_channel(c)
port = self.tc.request_port_forward('127.0.0.1', 0, handler)
self.assertEqual(port, self.server._listen.getsockname()[1])
cs = socket.socket()
cs.connect(('127.0.0.1', port))
ss, _ = self.server._listen.accept()
sch = self.ts.open_forwarded_tcpip_channel(ss.getsockname(),
ss.getpeername())
cch = self.tc.accept()
sch.send('hello')
self.assertEqual(b'hello', cch.recv(5))
sch.close()
cch.close()
ss.close()
cs.close()
# now cancel it.
self.tc.cancel_port_forward('127.0.0.1', port)
self.assertTrue(self.server._listen is None)
def test_F_port_forwarding(self):
"""
verify that a client can forward new connections from a locally-
forwarded port.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
# open a port on the "server" that the client will ask to forward to.
greeting_server = socket.socket()
greeting_server.bind(('127.0.0.1', 0))
greeting_server.listen(1)
greeting_port = greeting_server.getsockname()[1]
cs = self.tc.open_channel('direct-tcpip', ('127.0.0.1', greeting_port),
('', 9000))
sch = self.ts.accept(1.0)
cch = socket.socket()
cch.connect(self.server._tcpip_dest)
ss, _ = greeting_server.accept()
ss.send(b'Hello!\n')
ss.close()
sch.send(cch.recv(8192))
sch.close()
self.assertEqual(b'Hello!\n', cs.recv(7))
cs.close()
def test_G_stderr_select(self):
"""
verify that select() on a channel works even if only stderr is
receiving data.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
# nothing should be ready
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.send_stderr('hello\n')
# something should be ready now (give it 1 second to appear)
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(b'hello\n', chan.recv_stderr(6))
# and, should be dead again now
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.close()
chan.close()
def test_H_send_ready(self):
"""
verify that send_ready() indicates when a send would not block.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
self.assertEqual(chan.send_ready(), True)
total = 0
K = '*' * 1024
limit = 1 + (64 * 2**15)
while total < limit:
chan.send(K)
total += len(K)
if not chan.send_ready():
break
self.assertTrue(total < limit)
schan.close()
chan.close()
self.assertEqual(chan.send_ready(), True)
def test_I_rekey_deadlock(self):
"""
Regression test for deadlock when in-transit messages are received after MSG_KEXINIT is sent
Note: When this test fails, it may leak threads.
"""
# Test for an obscure deadlocking bug that can occur if we receive
# certain messages while initiating a key exchange.
#
# The deadlock occurs as follows:
#
# In the main thread:
# 1. The user's program calls Channel.send(), which sends
# MSG_CHANNEL_DATA to the remote host.
# 2. Packetizer discovers that REKEY_BYTES has been exceeded, and
# sets the __need_rekey flag.
#
# In the Transport thread:
# 3. Packetizer notices that the __need_rekey flag is set, and raises
# NeedRekeyException.
# 4. In response to NeedRekeyException, the transport thread sends
# MSG_KEXINIT to the remote host.
#
# On the remote host (using any SSH implementation):
# 5. The MSG_CHANNEL_DATA is received, and MSG_CHANNEL_WINDOW_ADJUST is sent.
# 6. The MSG_KEXINIT is received, and a corresponding MSG_KEXINIT is sent.
#
# In the main thread:
# 7. The user's program calls Channel.send().
# 8. Channel.send acquires Channel.lock, then calls Transport._send_user_message().
# 9. Transport._send_user_message waits for Transport.clear_to_send
# to be set (i.e., it waits for re-keying to complete).
# Channel.lock is still held.
#
# In the Transport thread:
# 10. MSG_CHANNEL_WINDOW_ADJUST is received; Channel._window_adjust
# is called to handle it.
# 11. Channel._window_adjust tries to acquire Channel.lock, but it
# blocks because the lock is already held by the main thread.
#
# The result is that the Transport thread never processes the remote
# host's MSG_KEXINIT packet, because it becomes deadlocked while
# handling the preceding MSG_CHANNEL_WINDOW_ADJUST message.
# We set up two separate threads for sending and receiving packets,
# while the main thread acts as a watchdog timer. If the timer
# expires, a deadlock is assumed.
class SendThread(threading.Thread):
def __init__(self, chan, iterations, done_event):
threading.Thread.__init__(self, None, None,
self.__class__.__name__)
self.setDaemon(True)
self.chan = chan
self.iterations = iterations
self.done_event = done_event
self.watchdog_event = threading.Event()
self.last = None
def run(self):
try:
for i in range(1, 1 + self.iterations):
if self.done_event.is_set():
break
self.watchdog_event.set()
#print i, "SEND"
self.chan.send("x" * 2048)
finally:
self.done_event.set()
self.watchdog_event.set()
class ReceiveThread(threading.Thread):
def __init__(self, chan, done_event):
threading.Thread.__init__(self, None, None,
self.__class__.__name__)
self.setDaemon(True)
self.chan = chan
self.done_event = done_event
self.watchdog_event = threading.Event()
def run(self):
try:
while not self.done_event.is_set():
if self.chan.recv_ready():
chan.recv(65536)
self.watchdog_event.set()
else:
if random.randint(0, 1):
time.sleep(random.randint(0, 500) / 1000.0)
finally:
self.done_event.set()
self.watchdog_event.set()
self.setup_test_server()
self.ts.packetizer.REKEY_BYTES = 2048
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
# Monkey patch the client's Transport._handler_table so that the client
# sends MSG_CHANNEL_WINDOW_ADJUST whenever it receives an initial
# MSG_KEXINIT. This is used to simulate the effect of network latency
# on a real MSG_CHANNEL_WINDOW_ADJUST message.
self.tc._handler_table = self.tc._handler_table.copy(
) # copy per-class dictionary
_negotiate_keys = self.tc._handler_table[MSG_KEXINIT]
def _negotiate_keys_wrapper(self, m):
if self.local_kex_init is None: # Remote side sent KEXINIT
# Simulate in-transit MSG_CHANNEL_WINDOW_ADJUST by sending it
# before responding to the incoming MSG_KEXINIT.
m2 = Message()
m2.add_byte(cMSG_CHANNEL_WINDOW_ADJUST)
m2.add_int(chan.remote_chanid)
m2.add_int(1) # bytes to add
self._send_message(m2)
return _negotiate_keys(self, m)
self.tc._handler_table[MSG_KEXINIT] = _negotiate_keys_wrapper
# Parameters for the test
iterations = 500 # The deadlock does not happen every time, but it
# should after many iterations.
timeout = 5
# This event is set when the test is completed
done_event = threading.Event()
# Start the sending thread
st = SendThread(schan, iterations, done_event)
st.start()
# Start the receiving thread
rt = ReceiveThread(chan, done_event)
rt.start()
# Act as a watchdog timer, checking
deadlocked = False
while not deadlocked and not done_event.is_set():
for event in (st.watchdog_event, rt.watchdog_event):
event.wait(timeout)
if done_event.is_set():
break
if not event.is_set():
deadlocked = True
break
event.clear()
# Tell the threads to stop (if they haven't already stopped). Note
# that if one or more threads are deadlocked, they might hang around
# forever (until the process exits).
done_event.set()
# Assertion: We must not have detected a timeout.
self.assertFalse(deadlocked)
# Close the channels
schan.close()
chan.close()
def test_J_sanitze_packet_size(self):
"""
verify that we conform to the rfc of packet and window sizes.
"""
for val, correct in [(4095, MIN_PACKET_SIZE),
(None, DEFAULT_MAX_PACKET_SIZE),
(2**32, MAX_WINDOW_SIZE)]:
self.assertEqual(self.tc._sanitize_packet_size(val), correct)
def test_K_sanitze_window_size(self):
"""
verify that we conform to the rfc of packet and window sizes.
"""
for val, correct in [(32767, MIN_WINDOW_SIZE),
(None, DEFAULT_WINDOW_SIZE),
(2**32, MAX_WINDOW_SIZE)]:
self.assertEqual(self.tc._sanitize_window_size(val), correct)
def test_L_handshake_timeout(self):
"""
verify that we can get a hanshake timeout.
"""
host_key = RSAKey.from_private_key_file(test_path('test_rsa.key'))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.tc.handshake_timeout = 0.000000000001
self.ts.start_server(event, server)
self.assertRaises(EOFError,
self.tc.connect,
hostkey=public_host_key,
username='******',
password='******')
class TransportTest(unittest.TestCase):
def setUp(self):
self.socks = LoopSocket()
self.sockc = LoopSocket()
self.sockc.link(self.socks)
self.tc = Transport(self.sockc)
self.ts = Transport(self.socks)
def tearDown(self):
self.tc.close()
self.ts.close()
self.socks.close()
self.sockc.close()
def setup_test_server(
self, client_options=None, server_options=None, connect_kwargs=None
):
host_key = RSAKey.from_private_key_file(_support("test_rsa.key"))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
if client_options is not None:
client_options(self.tc.get_security_options())
if server_options is not None:
server_options(self.ts.get_security_options())
event = threading.Event()
self.server = NullServer()
self.assertTrue(not event.is_set())
self.ts.start_server(event, self.server)
if connect_kwargs is None:
connect_kwargs = dict(
hostkey=public_host_key,
username="******",
password="******",
)
self.tc.connect(**connect_kwargs)
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
def test_security_options(self):
o = self.tc.get_security_options()
self.assertEqual(type(o), SecurityOptions)
self.assertTrue(("aes256-cbc", "blowfish-cbc") != o.ciphers)
o.ciphers = ("aes256-cbc", "blowfish-cbc")
self.assertEqual(("aes256-cbc", "blowfish-cbc"), o.ciphers)
try:
o.ciphers = ("aes256-cbc", "made-up-cipher")
self.assertTrue(False)
except ValueError:
pass
try:
o.ciphers = 23
self.assertTrue(False)
except TypeError:
pass
def testb_security_options_reset(self):
o = self.tc.get_security_options()
# should not throw any exceptions
o.ciphers = o.ciphers
o.digests = o.digests
o.key_types = o.key_types
o.kex = o.kex
o.compression = o.compression
def test_compute_key(self):
self.tc.K = 123281095979686581523377256114209720774539068973101330872763622971399429481072519713536292772709507296759612401802191955568143056534122385270077606457721553469730659233569339356140085284052436697480759510519672848743794433460113118986816826624865291116513647975790797391795651716378444844877749505443714557929 # noqa
self.tc.H = b"\x0C\x83\x07\xCD\xE6\x85\x6F\xF3\x0B\xA9\x36\x84\xEB\x0F\x04\xC2\x52\x0E\x9E\xD3" # noqa
self.tc.session_id = self.tc.H
key = self.tc._compute_key("C", 32)
self.assertEqual(
b"207E66594CA87C44ECCBA3B3CD39FDDB378E6FDB0F97C54B2AA0CFBF900CD995", # noqa
hexlify(key).upper(),
)
def test_simple(self):
"""
verify that we can establish an ssh link with ourselves across the
loopback sockets. this is hardly "simple" but it's simpler than the
later tests. :)
"""
host_key = RSAKey.from_private_key_file(_support("test_rsa.key"))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.assertEqual(None, self.tc.get_username())
self.assertEqual(None, self.ts.get_username())
self.assertEqual(False, self.tc.is_authenticated())
self.assertEqual(False, self.ts.is_authenticated())
self.ts.start_server(event, server)
self.tc.connect(
hostkey=public_host_key, username="******", password="******"
)
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
self.assertEqual("slowdive", self.tc.get_username())
self.assertEqual("slowdive", self.ts.get_username())
self.assertEqual(True, self.tc.is_authenticated())
self.assertEqual(True, self.ts.is_authenticated())
def testa_long_banner(self):
"""
verify that a long banner doesn't mess up the handshake.
"""
host_key = RSAKey.from_private_key_file(_support("test_rsa.key"))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.socks.send(LONG_BANNER)
self.ts.start_server(event, server)
self.tc.connect(
hostkey=public_host_key, username="******", password="******"
)
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
def test_special(self):
"""
verify that the client can demand odd handshake settings, and can
renegotiate keys in mid-stream.
"""
def force_algorithms(options):
options.ciphers = ("aes256-cbc",)
options.digests = ("hmac-md5-96",)
self.setup_test_server(client_options=force_algorithms)
self.assertEqual("aes256-cbc", self.tc.local_cipher)
self.assertEqual("aes256-cbc", self.tc.remote_cipher)
self.assertEqual(12, self.tc.packetizer.get_mac_size_out())
self.assertEqual(12, self.tc.packetizer.get_mac_size_in())
self.tc.send_ignore(1024)
self.tc.renegotiate_keys()
self.ts.send_ignore(1024)
@slow
def test_keepalive(self):
"""
verify that the keepalive will be sent.
"""
self.setup_test_server()
self.assertEqual(None, getattr(self.server, "_global_request", None))
self.tc.set_keepalive(1)
time.sleep(2)
self.assertEqual("*****@*****.**", self.server._global_request)
def test_exec_command(self):
"""
verify that exec_command() does something reasonable.
"""
self.setup_test_server()
chan = self.tc.open_session()
schan = self.ts.accept(1.0)
try:
chan.exec_command(
b"command contains \xfc and is not a valid UTF-8 string"
)
self.assertTrue(False)
except SSHException:
pass
chan = self.tc.open_session()
chan.exec_command("yes")
schan = self.ts.accept(1.0)
schan.send("Hello there.\n")
schan.send_stderr("This is on stderr.\n")
schan.close()
f = chan.makefile()
self.assertEqual("Hello there.\n", f.readline())
self.assertEqual("", f.readline())
f = chan.makefile_stderr()
self.assertEqual("This is on stderr.\n", f.readline())
self.assertEqual("", f.readline())
# now try it with combined stdout/stderr
chan = self.tc.open_session()
chan.exec_command("yes")
schan = self.ts.accept(1.0)
schan.send("Hello there.\n")
schan.send_stderr("This is on stderr.\n")
schan.close()
chan.set_combine_stderr(True)
f = chan.makefile()
self.assertEqual("Hello there.\n", f.readline())
self.assertEqual("This is on stderr.\n", f.readline())
self.assertEqual("", f.readline())
def testa_channel_can_be_used_as_context_manager(self):
"""
verify that exec_command() does something reasonable.
"""
self.setup_test_server()
with self.tc.open_session() as chan:
with self.ts.accept(1.0) as schan:
chan.exec_command("yes")
schan.send("Hello there.\n")
schan.close()
f = chan.makefile()
self.assertEqual("Hello there.\n", f.readline())
self.assertEqual("", f.readline())
def test_invoke_shell(self):
"""
verify that invoke_shell() does something reasonable.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
chan.send("communist j. cat\n")
f = schan.makefile()
self.assertEqual("communist j. cat\n", f.readline())
chan.close()
self.assertEqual("", f.readline())
def test_channel_exception(self):
"""
verify that ChannelException is thrown for a bad open-channel request.
"""
self.setup_test_server()
try:
self.tc.open_channel("bogus")
self.fail("expected exception")
except ChannelException as e:
self.assertTrue(e.code == OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED)
def test_exit_status(self):
"""
verify that get_exit_status() works.
"""
self.setup_test_server()
chan = self.tc.open_session()
schan = self.ts.accept(1.0)
chan.exec_command("yes")
schan.send("Hello there.\n")
self.assertTrue(not chan.exit_status_ready())
# trigger an EOF
schan.shutdown_read()
schan.shutdown_write()
schan.send_exit_status(23)
schan.close()
f = chan.makefile()
self.assertEqual("Hello there.\n", f.readline())
self.assertEqual("", f.readline())
count = 0
while not chan.exit_status_ready():
time.sleep(0.1)
count += 1
if count > 50:
raise Exception("timeout")
self.assertEqual(23, chan.recv_exit_status())
chan.close()
def test_select(self):
"""
verify that select() on a channel works.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
# nothing should be ready
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.send("hello\n")
# something should be ready now (give it 1 second to appear)
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(b"hello\n", chan.recv(6))
# and, should be dead again now
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.close()
# detect eof?
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(bytes(), chan.recv(16))
# make sure the pipe is still open for now...
p = chan._pipe
self.assertEqual(False, p._closed)
chan.close()
# ...and now is closed.
self.assertEqual(True, p._closed)
def test_renegotiate(self):
"""
verify that a transport can correctly renegotiate mid-stream.
"""
self.setup_test_server()
self.tc.packetizer.REKEY_BYTES = 16384
chan = self.tc.open_session()
chan.exec_command("yes")
schan = self.ts.accept(1.0)
self.assertEqual(self.tc.H, self.tc.session_id)
for i in range(20):
chan.send("x" * 1024)
chan.close()
# allow a few seconds for the rekeying to complete
for i in range(50):
if self.tc.H != self.tc.session_id:
break
time.sleep(0.1)
self.assertNotEqual(self.tc.H, self.tc.session_id)
schan.close()
def test_compression(self):
"""
verify that zlib compression is basically working.
"""
def force_compression(o):
o.compression = ("zlib",)
self.setup_test_server(force_compression, force_compression)
chan = self.tc.open_session()
chan.exec_command("yes")
schan = self.ts.accept(1.0)
bytes = self.tc.packetizer._Packetizer__sent_bytes
chan.send("x" * 1024)
bytes2 = self.tc.packetizer._Packetizer__sent_bytes
block_size = self.tc._cipher_info[self.tc.local_cipher]["block-size"]
mac_size = self.tc._mac_info[self.tc.local_mac]["size"]
# tests show this is actually compressed to *52 bytes*! including
# packet overhead! nice!! :)
self.assertTrue(bytes2 - bytes < 1024)
self.assertEqual(16 + block_size + mac_size, bytes2 - bytes)
chan.close()
schan.close()
def test_x11(self):
"""
verify that an x11 port can be requested and opened.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command("yes")
schan = self.ts.accept(1.0)
requested = []
def handler(c, addr_port):
addr, port = addr_port
requested.append((addr, port))
self.tc._queue_incoming_channel(c)
self.assertEqual(
None, getattr(self.server, "_x11_screen_number", None)
)
cookie = chan.request_x11(0, single_connection=True, handler=handler)
self.assertEqual(0, self.server._x11_screen_number)
self.assertEqual("MIT-MAGIC-COOKIE-1", self.server._x11_auth_protocol)
self.assertEqual(cookie, self.server._x11_auth_cookie)
self.assertEqual(True, self.server._x11_single_connection)
x11_server = self.ts.open_x11_channel(("localhost", 6093))
x11_client = self.tc.accept()
self.assertEqual("localhost", requested[0][0])
self.assertEqual(6093, requested[0][1])
x11_server.send("hello")
self.assertEqual(b"hello", x11_client.recv(5))
x11_server.close()
x11_client.close()
chan.close()
schan.close()
def test_reverse_port_forwarding(self):
"""
verify that a client can ask the server to open a reverse port for
forwarding.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command("yes")
self.ts.accept(1.0)
requested = []
def handler(c, origin_addr_port, server_addr_port):
requested.append(origin_addr_port)
requested.append(server_addr_port)
self.tc._queue_incoming_channel(c)
port = self.tc.request_port_forward("127.0.0.1", 0, handler)
self.assertEqual(port, self.server._listen.getsockname()[1])
cs = socket.socket()
cs.connect(("127.0.0.1", port))
ss, _ = self.server._listen.accept()
sch = self.ts.open_forwarded_tcpip_channel(
ss.getsockname(), ss.getpeername()
)
cch = self.tc.accept()
sch.send("hello")
self.assertEqual(b"hello", cch.recv(5))
sch.close()
cch.close()
ss.close()
cs.close()
# now cancel it.
self.tc.cancel_port_forward("127.0.0.1", port)
self.assertTrue(self.server._listen is None)
def test_port_forwarding(self):
"""
verify that a client can forward new connections from a locally-
forwarded port.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command("yes")
self.ts.accept(1.0)
# open a port on the "server" that the client will ask to forward to.
greeting_server = socket.socket()
greeting_server.bind(("127.0.0.1", 0))
greeting_server.listen(1)
greeting_port = greeting_server.getsockname()[1]
cs = self.tc.open_channel(
"direct-tcpip", ("127.0.0.1", greeting_port), ("", 9000)
)
sch = self.ts.accept(1.0)
cch = socket.socket()
cch.connect(self.server._tcpip_dest)
ss, _ = greeting_server.accept()
ss.send(b"Hello!\n")
ss.close()
sch.send(cch.recv(8192))
sch.close()
self.assertEqual(b"Hello!\n", cs.recv(7))
cs.close()
def test_stderr_select(self):
"""
verify that select() on a channel works even if only stderr is
receiving data.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
# nothing should be ready
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.send_stderr("hello\n")
# something should be ready now (give it 1 second to appear)
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(b"hello\n", chan.recv_stderr(6))
# and, should be dead again now
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.close()
chan.close()
def test_send_ready(self):
"""
verify that send_ready() indicates when a send would not block.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
self.assertEqual(chan.send_ready(), True)
total = 0
K = "*" * 1024
limit = 1 + (64 * 2 ** 15)
while total < limit:
chan.send(K)
total += len(K)
if not chan.send_ready():
break
self.assertTrue(total < limit)
schan.close()
chan.close()
self.assertEqual(chan.send_ready(), True)
def test_rekey_deadlock(self):
"""
Regression test for deadlock when in-transit messages are received
after MSG_KEXINIT is sent
Note: When this test fails, it may leak threads.
"""
# Test for an obscure deadlocking bug that can occur if we receive
# certain messages while initiating a key exchange.
#
# The deadlock occurs as follows:
#
# In the main thread:
# 1. The user's program calls Channel.send(), which sends
# MSG_CHANNEL_DATA to the remote host.
# 2. Packetizer discovers that REKEY_BYTES has been exceeded, and
# sets the __need_rekey flag.
#
# In the Transport thread:
# 3. Packetizer notices that the __need_rekey flag is set, and raises
# NeedRekeyException.
# 4. In response to NeedRekeyException, the transport thread sends
# MSG_KEXINIT to the remote host.
#
# On the remote host (using any SSH implementation):
# 5. The MSG_CHANNEL_DATA is received, and MSG_CHANNEL_WINDOW_ADJUST
# is sent.
# 6. The MSG_KEXINIT is received, and a corresponding MSG_KEXINIT is
# sent.
#
# In the main thread:
# 7. The user's program calls Channel.send().
# 8. Channel.send acquires Channel.lock, then calls
# Transport._send_user_message().
# 9. Transport._send_user_message waits for Transport.clear_to_send
# to be set (i.e., it waits for re-keying to complete).
# Channel.lock is still held.
#
# In the Transport thread:
# 10. MSG_CHANNEL_WINDOW_ADJUST is received; Channel._window_adjust
# is called to handle it.
# 11. Channel._window_adjust tries to acquire Channel.lock, but it
# blocks because the lock is already held by the main thread.
#
# The result is that the Transport thread never processes the remote
# host's MSG_KEXINIT packet, because it becomes deadlocked while
# handling the preceding MSG_CHANNEL_WINDOW_ADJUST message.
# We set up two separate threads for sending and receiving packets,
# while the main thread acts as a watchdog timer. If the timer
# expires, a deadlock is assumed.
class SendThread(threading.Thread):
def __init__(self, chan, iterations, done_event):
threading.Thread.__init__(
self, None, None, self.__class__.__name__
)
self.setDaemon(True)
self.chan = chan
self.iterations = iterations
self.done_event = done_event
self.watchdog_event = threading.Event()
self.last = None
def run(self):
try:
for i in range(1, 1 + self.iterations):
if self.done_event.is_set():
break
self.watchdog_event.set()
# print i, "SEND"
self.chan.send("x" * 2048)
finally:
self.done_event.set()
self.watchdog_event.set()
class ReceiveThread(threading.Thread):
def __init__(self, chan, done_event):
threading.Thread.__init__(
self, None, None, self.__class__.__name__
)
self.setDaemon(True)
self.chan = chan
self.done_event = done_event
self.watchdog_event = threading.Event()
def run(self):
try:
while not self.done_event.is_set():
if self.chan.recv_ready():
chan.recv(65536)
self.watchdog_event.set()
else:
if random.randint(0, 1):
time.sleep(random.randint(0, 500) / 1000.0)
finally:
self.done_event.set()
self.watchdog_event.set()
self.setup_test_server()
self.ts.packetizer.REKEY_BYTES = 2048
chan = self.tc.open_session()
chan.exec_command("yes")
schan = self.ts.accept(1.0)
# Monkey patch the client's Transport._handler_table so that the client
# sends MSG_CHANNEL_WINDOW_ADJUST whenever it receives an initial
# MSG_KEXINIT. This is used to simulate the effect of network latency
# on a real MSG_CHANNEL_WINDOW_ADJUST message.
self.tc._handler_table = (
self.tc._handler_table.copy()
) # copy per-class dictionary
_negotiate_keys = self.tc._handler_table[MSG_KEXINIT]
def _negotiate_keys_wrapper(self, m):
if self.local_kex_init is None: # Remote side sent KEXINIT
# Simulate in-transit MSG_CHANNEL_WINDOW_ADJUST by sending it
# before responding to the incoming MSG_KEXINIT.
m2 = Message()
m2.add_byte(cMSG_CHANNEL_WINDOW_ADJUST)
m2.add_int(chan.remote_chanid)
m2.add_int(1) # bytes to add
self._send_message(m2)
return _negotiate_keys(self, m)
self.tc._handler_table[MSG_KEXINIT] = _negotiate_keys_wrapper
# Parameters for the test
iterations = 500 # The deadlock does not happen every time, but it
# should after many iterations.
timeout = 5
# This event is set when the test is completed
done_event = threading.Event()
# Start the sending thread
st = SendThread(schan, iterations, done_event)
st.start()
# Start the receiving thread
rt = ReceiveThread(chan, done_event)
rt.start()
# Act as a watchdog timer, checking
deadlocked = False
while not deadlocked and not done_event.is_set():
for event in (st.watchdog_event, rt.watchdog_event):
event.wait(timeout)
if done_event.is_set():
break
if not event.is_set():
deadlocked = True
break
event.clear()
# Tell the threads to stop (if they haven't already stopped). Note
# that if one or more threads are deadlocked, they might hang around
# forever (until the process exits).
done_event.set()
# Assertion: We must not have detected a timeout.
self.assertFalse(deadlocked)
# Close the channels
schan.close()
chan.close()
def test_sanitze_packet_size(self):
"""
verify that we conform to the rfc of packet and window sizes.
"""
for val, correct in [
(4095, MIN_PACKET_SIZE),
(None, DEFAULT_MAX_PACKET_SIZE),
(2 ** 32, MAX_WINDOW_SIZE),
]:
self.assertEqual(self.tc._sanitize_packet_size(val), correct)
def test_sanitze_window_size(self):
"""
verify that we conform to the rfc of packet and window sizes.
"""
for val, correct in [
(32767, MIN_WINDOW_SIZE),
(None, DEFAULT_WINDOW_SIZE),
(2 ** 32, MAX_WINDOW_SIZE),
]:
self.assertEqual(self.tc._sanitize_window_size(val), correct)
@slow
def test_handshake_timeout(self):
"""
verify that we can get a hanshake timeout.
"""
# Tweak client Transport instance's Packetizer instance so
# its read_message() sleeps a bit. This helps prevent race conditions
# where the client Transport's timeout timer thread doesn't even have
# time to get scheduled before the main client thread finishes
# handshaking with the server.
# (Doing this on the server's transport *sounds* more 'correct' but
# actually doesn't work nearly as well for whatever reason.)
class SlowPacketizer(Packetizer):
def read_message(self):
time.sleep(1)
return super(SlowPacketizer, self).read_message()
# NOTE: prettttty sure since the replaced .packetizer Packetizer is now
# no longer doing anything with its copy of the socket...everything'll
# be fine. Even tho it's a bit squicky.
self.tc.packetizer = SlowPacketizer(self.tc.sock)
# Continue with regular test red tape.
host_key = RSAKey.from_private_key_file(_support("test_rsa.key"))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.tc.handshake_timeout = 0.000000000001
self.ts.start_server(event, server)
self.assertRaises(
EOFError,
self.tc.connect,
hostkey=public_host_key,
username="******",
password="******",
)
def test_select_after_close(self):
"""
verify that select works when a channel is already closed.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
schan.close()
# give client a moment to receive close notification
time.sleep(0.1)
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
def test_channel_send_misc(self):
"""
verify behaviours sending various instances to a channel
"""
self.setup_test_server()
text = u"\xa7 slice me nicely"
with self.tc.open_session() as chan:
schan = self.ts.accept(1.0)
if schan is None:
self.fail("Test server transport failed to accept")
sfile = schan.makefile()
# TypeError raised on non string or buffer type
self.assertRaises(TypeError, chan.send, object())
self.assertRaises(TypeError, chan.sendall, object())
# sendall() accepts a unicode instance
chan.sendall(text)
expected = text.encode("utf-8")
self.assertEqual(sfile.read(len(expected)), expected)
@needs_builtin("buffer")
def test_channel_send_buffer(self):
"""
verify sending buffer instances to a channel
"""
self.setup_test_server()
data = 3 * b"some test data\n whole"
with self.tc.open_session() as chan:
schan = self.ts.accept(1.0)
if schan is None:
self.fail("Test server transport failed to accept")
sfile = schan.makefile()
# send() accepts buffer instances
sent = 0
while sent < len(data):
sent += chan.send(buffer(data, sent, 8)) # noqa
self.assertEqual(sfile.read(len(data)), data)
# sendall() accepts a buffer instance
chan.sendall(buffer(data)) # noqa
self.assertEqual(sfile.read(len(data)), data)
@needs_builtin("memoryview")
def test_channel_send_memoryview(self):
"""
verify sending memoryview instances to a channel
"""
self.setup_test_server()
data = 3 * b"some test data\n whole"
with self.tc.open_session() as chan:
schan = self.ts.accept(1.0)
if schan is None:
self.fail("Test server transport failed to accept")
sfile = schan.makefile()
# send() accepts memoryview slices
sent = 0
view = memoryview(data)
while sent < len(view):
sent += chan.send(view[sent : sent + 8])
self.assertEqual(sfile.read(len(data)), data)
# sendall() accepts a memoryview instance
chan.sendall(memoryview(data))
self.assertEqual(sfile.read(len(data)), data)
def test_server_rejects_open_channel_without_auth(self):
try:
self.setup_test_server(connect_kwargs={})
self.tc.open_session()
except ChannelException as e:
assert e.code == OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED
else:
assert False, "Did not raise ChannelException!"
def test_server_rejects_arbitrary_global_request_without_auth(self):
self.setup_test_server(connect_kwargs={})
# NOTE: this dummy global request kind would normally pass muster
# from the test server.
self.tc.global_request("acceptable")
# Global requests never raise exceptions, even on failure (not sure why
# this was the original design...ugh.) Best we can do to tell failure
# happened is that the client transport's global_response was set back
# to None; if it had succeeded, it would be the response Message.
err = "Unauthed global response incorrectly succeeded!"
assert self.tc.global_response is None, err
def test_server_rejects_port_forward_without_auth(self):
# NOTE: at protocol level port forward requests are treated same as a
# regular global request, but Paramiko server implements a special-case
# method for it, so it gets its own test. (plus, THAT actually raises
# an exception on the client side, unlike the general case...)
self.setup_test_server(connect_kwargs={})
try:
self.tc.request_port_forward("localhost", 1234)
except SSHException as e:
assert "forwarding request denied" in str(e)
else:
assert False, "Did not raise SSHException!"
def _send_unimplemented(self, server_is_sender):
self.setup_test_server()
sender, recipient = self.tc, self.ts
if server_is_sender:
sender, recipient = self.ts, self.tc
recipient._send_message = Mock()
msg = Message()
msg.add_byte(cMSG_UNIMPLEMENTED)
sender._send_message(msg)
# TODO: I hate this but I literally don't see a good way to know when
# the recipient has received the sender's message (there are no
# existing threading events in play that work for this), esp in this
# case where we don't WANT a response (as otherwise we could
# potentially try blocking on the sender's receipt of a reply...maybe).
time.sleep(0.1)
assert not recipient._send_message.called
def test_server_does_not_respond_to_MSG_UNIMPLEMENTED(self):
self._send_unimplemented(server_is_sender=False)
def test_client_does_not_respond_to_MSG_UNIMPLEMENTED(self):
self._send_unimplemented(server_is_sender=True)
def _send_client_message(self, message_type):
self.setup_test_server(connect_kwargs={})
self.ts._send_message = Mock()
# NOTE: this isn't 100% realistic (most of these message types would
# have actual other fields in 'em) but it suffices to test the level of
# message dispatch we're interested in here.
msg = Message()
# TODO: really not liking the whole cMSG_XXX vs MSG_XXX duality right
# now, esp since the former is almost always just byte_chr(the
# latter)...but since that's the case...
msg.add_byte(byte_chr(message_type))
self.tc._send_message(msg)
# No good way to actually wait for server action (see above tests re:
# MSG_UNIMPLEMENTED). Grump.
time.sleep(0.1)
def _expect_unimplemented(self):
# Ensure MSG_UNIMPLEMENTED was sent (implies it hit end of loop instead
# of truly handling the given message).
# NOTE: When bug present, this will actually be the first thing that
# fails (since in many cases actual message handling doesn't involve
# sending a message back right away).
assert self.ts._send_message.call_count == 1
reply = self.ts._send_message.call_args[0][0]
reply.rewind() # Because it's pre-send, not post-receive
assert reply.get_byte() == cMSG_UNIMPLEMENTED
def test_server_transports_reject_client_message_types(self):
# TODO: handle Transport's own tables too, not just its inner auth
# handler's table. See TODOs in auth_handler.py
for message_type in AuthHandler._client_handler_table:
self._send_client_message(message_type)
self._expect_unimplemented()
# Reset for rest of loop
self.tearDown()
self.setUp()
def test_server_rejects_client_MSG_USERAUTH_SUCCESS(self):
self._send_client_message(MSG_USERAUTH_SUCCESS)
# Sanity checks
assert not self.ts.authenticated
assert not self.ts.auth_handler.authenticated
# Real fix's behavior
self._expect_unimplemented()
class TransportTest(unittest.TestCase):
def setUp(self):
self.socks = LoopSocket()
self.sockc = LoopSocket()
self.sockc.link(self.socks)
self.tc = Transport(self.sockc)
self.ts = Transport(self.socks)
def tearDown(self):
self.tc.close()
self.ts.close()
self.socks.close()
self.sockc.close()
def setup_test_server(
self, client_options=None, server_options=None, connect_kwargs=None,
):
host_key = RSAKey.from_private_key_file(_support('test_rsa.key'))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
if client_options is not None:
client_options(self.tc.get_security_options())
if server_options is not None:
server_options(self.ts.get_security_options())
event = threading.Event()
self.server = NullServer()
self.assertTrue(not event.is_set())
self.ts.start_server(event, self.server)
if connect_kwargs is None:
connect_kwargs = dict(
hostkey=public_host_key,
username='******',
password='******',
)
self.tc.connect(**connect_kwargs)
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
def test_1_security_options(self):
o = self.tc.get_security_options()
self.assertEqual(type(o), SecurityOptions)
self.assertTrue(('aes256-cbc', 'blowfish-cbc') != o.ciphers)
o.ciphers = ('aes256-cbc', 'blowfish-cbc')
self.assertEqual(('aes256-cbc', 'blowfish-cbc'), o.ciphers)
try:
o.ciphers = ('aes256-cbc', 'made-up-cipher')
self.assertTrue(False)
except ValueError:
pass
try:
o.ciphers = 23
self.assertTrue(False)
except TypeError:
pass
def test_1b_security_options_reset(self):
o = self.tc.get_security_options()
# should not throw any exceptions
o.ciphers = o.ciphers
o.digests = o.digests
o.key_types = o.key_types
o.kex = o.kex
o.compression = o.compression
def test_2_compute_key(self):
self.tc.K = 123281095979686581523377256114209720774539068973101330872763622971399429481072519713536292772709507296759612401802191955568143056534122385270077606457721553469730659233569339356140085284052436697480759510519672848743794433460113118986816826624865291116513647975790797391795651716378444844877749505443714557929
self.tc.H = b'\x0C\x83\x07\xCD\xE6\x85\x6F\xF3\x0B\xA9\x36\x84\xEB\x0F\x04\xC2\x52\x0E\x9E\xD3'
self.tc.session_id = self.tc.H
key = self.tc._compute_key('C', 32)
self.assertEqual(b'207E66594CA87C44ECCBA3B3CD39FDDB378E6FDB0F97C54B2AA0CFBF900CD995',
hexlify(key).upper())
def test_3_simple(self):
"""
verify that we can establish an ssh link with ourselves across the
loopback sockets. this is hardly "simple" but it's simpler than the
later tests. :)
"""
host_key = RSAKey.from_private_key_file(_support('test_rsa.key'))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.assertEqual(None, self.tc.get_username())
self.assertEqual(None, self.ts.get_username())
self.assertEqual(False, self.tc.is_authenticated())
self.assertEqual(False, self.ts.is_authenticated())
self.ts.start_server(event, server)
self.tc.connect(hostkey=public_host_key,
username='******', password='******')
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
self.assertEqual('slowdive', self.tc.get_username())
self.assertEqual('slowdive', self.ts.get_username())
self.assertEqual(True, self.tc.is_authenticated())
self.assertEqual(True, self.ts.is_authenticated())
def test_3a_long_banner(self):
"""
verify that a long banner doesn't mess up the handshake.
"""
host_key = RSAKey.from_private_key_file(_support('test_rsa.key'))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.socks.send(LONG_BANNER)
self.ts.start_server(event, server)
self.tc.connect(hostkey=public_host_key,
username='******', password='******')
event.wait(1.0)
self.assertTrue(event.is_set())
self.assertTrue(self.ts.is_active())
def test_4_special(self):
"""
verify that the client can demand odd handshake settings, and can
renegotiate keys in mid-stream.
"""
def force_algorithms(options):
options.ciphers = ('aes256-cbc',)
options.digests = ('hmac-md5-96',)
self.setup_test_server(client_options=force_algorithms)
self.assertEqual('aes256-cbc', self.tc.local_cipher)
self.assertEqual('aes256-cbc', self.tc.remote_cipher)
self.assertEqual(12, self.tc.packetizer.get_mac_size_out())
self.assertEqual(12, self.tc.packetizer.get_mac_size_in())
self.tc.send_ignore(1024)
self.tc.renegotiate_keys()
self.ts.send_ignore(1024)
@slow
def test_5_keepalive(self):
"""
verify that the keepalive will be sent.
"""
self.setup_test_server()
self.assertEqual(None, getattr(self.server, '_global_request', None))
self.tc.set_keepalive(1)
time.sleep(2)
self.assertEqual('*****@*****.**', self.server._global_request)
def test_6_exec_command(self):
"""
verify that exec_command() does something reasonable.
"""
self.setup_test_server()
chan = self.tc.open_session()
schan = self.ts.accept(1.0)
try:
chan.exec_command(b'command contains \xfc and is not a valid UTF-8 string')
self.assertTrue(False)
except SSHException:
pass
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
schan.send('Hello there.\n')
schan.send_stderr('This is on stderr.\n')
schan.close()
f = chan.makefile()
self.assertEqual('Hello there.\n', f.readline())
self.assertEqual('', f.readline())
f = chan.makefile_stderr()
self.assertEqual('This is on stderr.\n', f.readline())
self.assertEqual('', f.readline())
# now try it with combined stdout/stderr
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
schan.send('Hello there.\n')
schan.send_stderr('This is on stderr.\n')
schan.close()
chan.set_combine_stderr(True)
f = chan.makefile()
self.assertEqual('Hello there.\n', f.readline())
self.assertEqual('This is on stderr.\n', f.readline())
self.assertEqual('', f.readline())
def test_6a_channel_can_be_used_as_context_manager(self):
"""
verify that exec_command() does something reasonable.
"""
self.setup_test_server()
with self.tc.open_session() as chan:
with self.ts.accept(1.0) as schan:
chan.exec_command('yes')
schan.send('Hello there.\n')
schan.close()
f = chan.makefile()
self.assertEqual('Hello there.\n', f.readline())
self.assertEqual('', f.readline())
def test_7_invoke_shell(self):
"""
verify that invoke_shell() does something reasonable.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
chan.send('communist j. cat\n')
f = schan.makefile()
self.assertEqual('communist j. cat\n', f.readline())
chan.close()
self.assertEqual('', f.readline())
def test_8_channel_exception(self):
"""
verify that ChannelException is thrown for a bad open-channel request.
"""
self.setup_test_server()
try:
chan = self.tc.open_channel('bogus')
self.fail('expected exception')
except ChannelException as e:
self.assertTrue(e.code == OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED)
def test_9_exit_status(self):
"""
verify that get_exit_status() works.
"""
self.setup_test_server()
chan = self.tc.open_session()
schan = self.ts.accept(1.0)
chan.exec_command('yes')
schan.send('Hello there.\n')
self.assertTrue(not chan.exit_status_ready())
# trigger an EOF
schan.shutdown_read()
schan.shutdown_write()
schan.send_exit_status(23)
schan.close()
f = chan.makefile()
self.assertEqual('Hello there.\n', f.readline())
self.assertEqual('', f.readline())
count = 0
while not chan.exit_status_ready():
time.sleep(0.1)
count += 1
if count > 50:
raise Exception("timeout")
self.assertEqual(23, chan.recv_exit_status())
chan.close()
def test_A_select(self):
"""
verify that select() on a channel works.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
# nothing should be ready
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.send('hello\n')
# something should be ready now (give it 1 second to appear)
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(b'hello\n', chan.recv(6))
# and, should be dead again now
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.close()
# detect eof?
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(bytes(), chan.recv(16))
# make sure the pipe is still open for now...
p = chan._pipe
self.assertEqual(False, p._closed)
chan.close()
# ...and now is closed.
self.assertEqual(True, p._closed)
def test_B_renegotiate(self):
"""
verify that a transport can correctly renegotiate mid-stream.
"""
self.setup_test_server()
self.tc.packetizer.REKEY_BYTES = 16384
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
self.assertEqual(self.tc.H, self.tc.session_id)
for i in range(20):
chan.send('x' * 1024)
chan.close()
# allow a few seconds for the rekeying to complete
for i in range(50):
if self.tc.H != self.tc.session_id:
break
time.sleep(0.1)
self.assertNotEqual(self.tc.H, self.tc.session_id)
schan.close()
def test_C_compression(self):
"""
verify that zlib compression is basically working.
"""
def force_compression(o):
o.compression = ('zlib',)
self.setup_test_server(force_compression, force_compression)
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
bytes = self.tc.packetizer._Packetizer__sent_bytes
chan.send('x' * 1024)
bytes2 = self.tc.packetizer._Packetizer__sent_bytes
block_size = self.tc._cipher_info[self.tc.local_cipher]['block-size']
mac_size = self.tc._mac_info[self.tc.local_mac]['size']
# tests show this is actually compressed to *52 bytes*! including packet overhead! nice!! :)
self.assertTrue(bytes2 - bytes < 1024)
self.assertEqual(16 + block_size + mac_size, bytes2 - bytes)
chan.close()
schan.close()
def test_D_x11(self):
"""
verify that an x11 port can be requested and opened.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
requested = []
def handler(c, addr_port):
addr, port = addr_port
requested.append((addr, port))
self.tc._queue_incoming_channel(c)
self.assertEqual(None, getattr(self.server, '_x11_screen_number', None))
cookie = chan.request_x11(0, single_connection=True, handler=handler)
self.assertEqual(0, self.server._x11_screen_number)
self.assertEqual('MIT-MAGIC-COOKIE-1', self.server._x11_auth_protocol)
self.assertEqual(cookie, self.server._x11_auth_cookie)
self.assertEqual(True, self.server._x11_single_connection)
x11_server = self.ts.open_x11_channel(('localhost', 6093))
x11_client = self.tc.accept()
self.assertEqual('localhost', requested[0][0])
self.assertEqual(6093, requested[0][1])
x11_server.send('hello')
self.assertEqual(b'hello', x11_client.recv(5))
x11_server.close()
x11_client.close()
chan.close()
schan.close()
def test_E_reverse_port_forwarding(self):
"""
verify that a client can ask the server to open a reverse port for
forwarding.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
requested = []
def handler(c, origin_addr_port, server_addr_port):
requested.append(origin_addr_port)
requested.append(server_addr_port)
self.tc._queue_incoming_channel(c)
port = self.tc.request_port_forward('127.0.0.1', 0, handler)
self.assertEqual(port, self.server._listen.getsockname()[1])
cs = socket.socket()
cs.connect(('127.0.0.1', port))
ss, _ = self.server._listen.accept()
sch = self.ts.open_forwarded_tcpip_channel(ss.getsockname(), ss.getpeername())
cch = self.tc.accept()
sch.send('hello')
self.assertEqual(b'hello', cch.recv(5))
sch.close()
cch.close()
ss.close()
cs.close()
# now cancel it.
self.tc.cancel_port_forward('127.0.0.1', port)
self.assertTrue(self.server._listen is None)
def test_F_port_forwarding(self):
"""
verify that a client can forward new connections from a locally-
forwarded port.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
# open a port on the "server" that the client will ask to forward to.
greeting_server = socket.socket()
greeting_server.bind(('127.0.0.1', 0))
greeting_server.listen(1)
greeting_port = greeting_server.getsockname()[1]
cs = self.tc.open_channel('direct-tcpip', ('127.0.0.1', greeting_port), ('', 9000))
sch = self.ts.accept(1.0)
cch = socket.socket()
cch.connect(self.server._tcpip_dest)
ss, _ = greeting_server.accept()
ss.send(b'Hello!\n')
ss.close()
sch.send(cch.recv(8192))
sch.close()
self.assertEqual(b'Hello!\n', cs.recv(7))
cs.close()
def test_G_stderr_select(self):
"""
verify that select() on a channel works even if only stderr is
receiving data.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
# nothing should be ready
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.send_stderr('hello\n')
# something should be ready now (give it 1 second to appear)
for i in range(10):
r, w, e = select.select([chan], [], [], 0.1)
if chan in r:
break
time.sleep(0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
self.assertEqual(b'hello\n', chan.recv_stderr(6))
# and, should be dead again now
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([], r)
self.assertEqual([], w)
self.assertEqual([], e)
schan.close()
chan.close()
def test_H_send_ready(self):
"""
verify that send_ready() indicates when a send would not block.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
self.assertEqual(chan.send_ready(), True)
total = 0
K = '*' * 1024
limit = 1+(64 * 2 ** 15)
while total < limit:
chan.send(K)
total += len(K)
if not chan.send_ready():
break
self.assertTrue(total < limit)
schan.close()
chan.close()
self.assertEqual(chan.send_ready(), True)
def test_I_rekey_deadlock(self):
"""
Regression test for deadlock when in-transit messages are received after MSG_KEXINIT is sent
Note: When this test fails, it may leak threads.
"""
# Test for an obscure deadlocking bug that can occur if we receive
# certain messages while initiating a key exchange.
#
# The deadlock occurs as follows:
#
# In the main thread:
# 1. The user's program calls Channel.send(), which sends
# MSG_CHANNEL_DATA to the remote host.
# 2. Packetizer discovers that REKEY_BYTES has been exceeded, and
# sets the __need_rekey flag.
#
# In the Transport thread:
# 3. Packetizer notices that the __need_rekey flag is set, and raises
# NeedRekeyException.
# 4. In response to NeedRekeyException, the transport thread sends
# MSG_KEXINIT to the remote host.
#
# On the remote host (using any SSH implementation):
# 5. The MSG_CHANNEL_DATA is received, and MSG_CHANNEL_WINDOW_ADJUST is sent.
# 6. The MSG_KEXINIT is received, and a corresponding MSG_KEXINIT is sent.
#
# In the main thread:
# 7. The user's program calls Channel.send().
# 8. Channel.send acquires Channel.lock, then calls Transport._send_user_message().
# 9. Transport._send_user_message waits for Transport.clear_to_send
# to be set (i.e., it waits for re-keying to complete).
# Channel.lock is still held.
#
# In the Transport thread:
# 10. MSG_CHANNEL_WINDOW_ADJUST is received; Channel._window_adjust
# is called to handle it.
# 11. Channel._window_adjust tries to acquire Channel.lock, but it
# blocks because the lock is already held by the main thread.
#
# The result is that the Transport thread never processes the remote
# host's MSG_KEXINIT packet, because it becomes deadlocked while
# handling the preceding MSG_CHANNEL_WINDOW_ADJUST message.
# We set up two separate threads for sending and receiving packets,
# while the main thread acts as a watchdog timer. If the timer
# expires, a deadlock is assumed.
class SendThread(threading.Thread):
def __init__(self, chan, iterations, done_event):
threading.Thread.__init__(self, None, None, self.__class__.__name__)
self.setDaemon(True)
self.chan = chan
self.iterations = iterations
self.done_event = done_event
self.watchdog_event = threading.Event()
self.last = None
def run(self):
try:
for i in range(1, 1+self.iterations):
if self.done_event.is_set():
break
self.watchdog_event.set()
#print i, "SEND"
self.chan.send("x" * 2048)
finally:
self.done_event.set()
self.watchdog_event.set()
class ReceiveThread(threading.Thread):
def __init__(self, chan, done_event):
threading.Thread.__init__(self, None, None, self.__class__.__name__)
self.setDaemon(True)
self.chan = chan
self.done_event = done_event
self.watchdog_event = threading.Event()
def run(self):
try:
while not self.done_event.is_set():
if self.chan.recv_ready():
chan.recv(65536)
self.watchdog_event.set()
else:
if random.randint(0, 1):
time.sleep(random.randint(0, 500) / 1000.0)
finally:
self.done_event.set()
self.watchdog_event.set()
self.setup_test_server()
self.ts.packetizer.REKEY_BYTES = 2048
chan = self.tc.open_session()
chan.exec_command('yes')
schan = self.ts.accept(1.0)
# Monkey patch the client's Transport._handler_table so that the client
# sends MSG_CHANNEL_WINDOW_ADJUST whenever it receives an initial
# MSG_KEXINIT. This is used to simulate the effect of network latency
# on a real MSG_CHANNEL_WINDOW_ADJUST message.
self.tc._handler_table = self.tc._handler_table.copy() # copy per-class dictionary
_negotiate_keys = self.tc._handler_table[MSG_KEXINIT]
def _negotiate_keys_wrapper(self, m):
if self.local_kex_init is None: # Remote side sent KEXINIT
# Simulate in-transit MSG_CHANNEL_WINDOW_ADJUST by sending it
# before responding to the incoming MSG_KEXINIT.
m2 = Message()
m2.add_byte(cMSG_CHANNEL_WINDOW_ADJUST)
m2.add_int(chan.remote_chanid)
m2.add_int(1) # bytes to add
self._send_message(m2)
return _negotiate_keys(self, m)
self.tc._handler_table[MSG_KEXINIT] = _negotiate_keys_wrapper
# Parameters for the test
iterations = 500 # The deadlock does not happen every time, but it
# should after many iterations.
timeout = 5
# This event is set when the test is completed
done_event = threading.Event()
# Start the sending thread
st = SendThread(schan, iterations, done_event)
st.start()
# Start the receiving thread
rt = ReceiveThread(chan, done_event)
rt.start()
# Act as a watchdog timer, checking
deadlocked = False
while not deadlocked and not done_event.is_set():
for event in (st.watchdog_event, rt.watchdog_event):
event.wait(timeout)
if done_event.is_set():
break
if not event.is_set():
deadlocked = True
break
event.clear()
# Tell the threads to stop (if they haven't already stopped). Note
# that if one or more threads are deadlocked, they might hang around
# forever (until the process exits).
done_event.set()
# Assertion: We must not have detected a timeout.
self.assertFalse(deadlocked)
# Close the channels
schan.close()
chan.close()
def test_J_sanitze_packet_size(self):
"""
verify that we conform to the rfc of packet and window sizes.
"""
for val, correct in [(4095, MIN_PACKET_SIZE),
(None, DEFAULT_MAX_PACKET_SIZE),
(2**32, MAX_WINDOW_SIZE)]:
self.assertEqual(self.tc._sanitize_packet_size(val), correct)
def test_K_sanitze_window_size(self):
"""
verify that we conform to the rfc of packet and window sizes.
"""
for val, correct in [(32767, MIN_WINDOW_SIZE),
(None, DEFAULT_WINDOW_SIZE),
(2**32, MAX_WINDOW_SIZE)]:
self.assertEqual(self.tc._sanitize_window_size(val), correct)
@slow
def test_L_handshake_timeout(self):
"""
verify that we can get a hanshake timeout.
"""
# Tweak client Transport instance's Packetizer instance so
# its read_message() sleeps a bit. This helps prevent race conditions
# where the client Transport's timeout timer thread doesn't even have
# time to get scheduled before the main client thread finishes
# handshaking with the server.
# (Doing this on the server's transport *sounds* more 'correct' but
# actually doesn't work nearly as well for whatever reason.)
class SlowPacketizer(Packetizer):
def read_message(self):
time.sleep(1)
return super(SlowPacketizer, self).read_message()
# NOTE: prettttty sure since the replaced .packetizer Packetizer is now
# no longer doing anything with its copy of the socket...everything'll
# be fine. Even tho it's a bit squicky.
self.tc.packetizer = SlowPacketizer(self.tc.sock)
# Continue with regular test red tape.
host_key = RSAKey.from_private_key_file(_support('test_rsa.key'))
public_host_key = RSAKey(data=host_key.asbytes())
self.ts.add_server_key(host_key)
event = threading.Event()
server = NullServer()
self.assertTrue(not event.is_set())
self.tc.handshake_timeout = 0.000000000001
self.ts.start_server(event, server)
self.assertRaises(EOFError, self.tc.connect,
hostkey=public_host_key,
username='******',
password='******')
def test_M_select_after_close(self):
"""
verify that select works when a channel is already closed.
"""
self.setup_test_server()
chan = self.tc.open_session()
chan.invoke_shell()
schan = self.ts.accept(1.0)
schan.close()
# give client a moment to receive close notification
time.sleep(0.1)
r, w, e = select.select([chan], [], [], 0.1)
self.assertEqual([chan], r)
self.assertEqual([], w)
self.assertEqual([], e)
def test_channel_send_misc(self):
"""
verify behaviours sending various instances to a channel
"""
self.setup_test_server()
text = u"\xa7 slice me nicely"
with self.tc.open_session() as chan:
schan = self.ts.accept(1.0)
if schan is None:
self.fail("Test server transport failed to accept")
sfile = schan.makefile()
# TypeError raised on non string or buffer type
self.assertRaises(TypeError, chan.send, object())
self.assertRaises(TypeError, chan.sendall, object())
# sendall() accepts a unicode instance
chan.sendall(text)
expected = text.encode("utf-8")
self.assertEqual(sfile.read(len(expected)), expected)
@needs_builtin('buffer')
def test_channel_send_buffer(self):
"""
verify sending buffer instances to a channel
"""
self.setup_test_server()
data = 3 * b'some test data\n whole'
with self.tc.open_session() as chan:
schan = self.ts.accept(1.0)
if schan is None:
self.fail("Test server transport failed to accept")
sfile = schan.makefile()
# send() accepts buffer instances
sent = 0
while sent < len(data):
sent += chan.send(buffer(data, sent, 8))
self.assertEqual(sfile.read(len(data)), data)
# sendall() accepts a buffer instance
chan.sendall(buffer(data))
self.assertEqual(sfile.read(len(data)), data)
@needs_builtin('memoryview')
def test_channel_send_memoryview(self):
"""
verify sending memoryview instances to a channel
"""
self.setup_test_server()
data = 3 * b'some test data\n whole'
with self.tc.open_session() as chan:
schan = self.ts.accept(1.0)
if schan is None:
self.fail("Test server transport failed to accept")
sfile = schan.makefile()
# send() accepts memoryview slices
sent = 0
view = memoryview(data)
while sent < len(view):
sent += chan.send(view[sent:sent+8])
self.assertEqual(sfile.read(len(data)), data)
# sendall() accepts a memoryview instance
chan.sendall(memoryview(data))
self.assertEqual(sfile.read(len(data)), data)
def test_server_rejects_open_channel_without_auth(self):
try:
self.setup_test_server(connect_kwargs={})
self.tc.open_session()
except ChannelException as e:
assert e.code == OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED
else:
assert False, "Did not raise ChannelException!"
def test_server_rejects_arbitrary_global_request_without_auth(self):
self.setup_test_server(connect_kwargs={})
# NOTE: this dummy global request kind would normally pass muster
# from the test server.
self.tc.global_request('acceptable')
# Global requests never raise exceptions, even on failure (not sure why
# this was the original design...ugh.) Best we can do to tell failure
# happened is that the client transport's global_response was set back
# to None; if it had succeeded, it would be the response Message.
err = "Unauthed global response incorrectly succeeded!"
assert self.tc.global_response is None, err
def test_server_rejects_port_forward_without_auth(self):
# NOTE: at protocol level port forward requests are treated same as a
# regular global request, but Paramiko server implements a special-case
# method for it, so it gets its own test. (plus, THAT actually raises
# an exception on the client side, unlike the general case...)
self.setup_test_server(connect_kwargs={})
try:
self.tc.request_port_forward('localhost', 1234)
except SSHException as e:
assert "forwarding request denied" in str(e)
else:
assert False, "Did not raise SSHException!"
