aboutsummaryrefslogtreecommitdiffstats
path: root/yardstick/ssh.py
blob: 6bc6010f7fc02fbb7dd179363f2096202f12645d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
# Copyright 2013: Mirantis Inc.
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

# yardstick comment: this is a modified copy of rally/rally/common/sshutils.py

"""High level ssh library.

Usage examples:

Execute command and get output:

    ssh = sshclient.SSH("root", "example.com", port=33)
    status, stdout, stderr = ssh.execute("ps ax")
    if status:
        raise Exception("Command failed with non-zero status.")
    print(stdout.splitlines())

Execute command with huge output:

    class PseudoFile(io.RawIOBase):
        def write(chunk):
            if "error" in chunk:
                email_admin(chunk)

    ssh = SSH("root", "example.com")
    with PseudoFile() as p:
        ssh.run("tail -f /var/log/syslog", stdout=p, timeout=False)

Execute local script on remote side:

    ssh = sshclient.SSH("user", "example.com")

    with open("~/myscript.sh", "r") as stdin_file:
        status, out, err = ssh.execute('/bin/sh -s "arg1" "arg2"',
                                       stdin=stdin_file)

Upload file:

    ssh = SSH("user", "example.com")
    # use rb for binary files
    with open("/store/file.gz", "rb") as stdin_file:
        ssh.run("cat > ~/upload/file.gz", stdin=stdin_file)

Eventlet:

    eventlet.monkey_patch(select=True, time=True)
    or
    eventlet.monkey_patch()
    or
    sshclient = eventlet.import_patched("yardstick.ssh")

"""
import io
import logging
import os
import re
import select
import socket
import time

import paramiko
from chainmap import ChainMap
from oslo_utils import encodeutils
from scp import SCPClient
import six

from yardstick.common import exceptions
from yardstick.common.utils import try_int, NON_NONE_DEFAULT, make_dict_from_map
from yardstick.network_services.utils import provision_tool

LOG = logging.getLogger(__name__)

def convert_key_to_str(key):
    if not isinstance(key, (paramiko.RSAKey, paramiko.DSSKey)):
        return key
    k = io.StringIO()
    key.write_private_key(k)
    return k.getvalue()


class SSH(object):
    """Represent ssh connection."""

    SSH_PORT = paramiko.config.SSH_PORT
    DEFAULT_WAIT_TIMEOUT = 120

    @staticmethod
    def gen_keys(key_filename, bit_count=2048):
        rsa_key = paramiko.RSAKey.generate(bits=bit_count, progress_func=None)
        rsa_key.write_private_key_file(key_filename)
        print("Writing %s ..." % key_filename)
        with open('.'.join([key_filename, "pub"]), "w") as pubkey_file:
            pubkey_file.write(rsa_key.get_name())
            pubkey_file.write(' ')
            pubkey_file.write(rsa_key.get_base64())
            pubkey_file.write('\n')

    @staticmethod
    def get_class():
        # must return static class name, anything else refers to the calling class
        # i.e. the subclass, not the superclass
        return SSH

    @classmethod
    def get_arg_key_map(cls):
        return {
            'user': ('user', NON_NONE_DEFAULT),
            'host': ('ip', NON_NONE_DEFAULT),
            'port': ('ssh_port', cls.SSH_PORT),
            'pkey': ('pkey', None),
            'key_filename': ('key_filename', None),
            'password': ('password', None),
            'name': ('name', None),
        }

    def __init__(self, user, host, port=None, pkey=None,
                 key_filename=None, password=None, name=None):
        """Initialize SSH client.

        :param user: ssh username
        :param host: hostname or ip address of remote ssh server
        :param port: remote ssh port
        :param pkey: RSA or DSS private key string or file object
        :param key_filename: private key filename
        :param password: password
        """
        self.name = name
        if name:
            self.log = logging.getLogger(__name__ + '.' + self.name)
        else:
            self.log = logging.getLogger(__name__)

        self.wait_timeout = self.DEFAULT_WAIT_TIMEOUT
        self.user = user
        self.host = host
        # everybody wants to debug this in the caller, do it here instead
        self.log.debug("user:%s host:%s", user, host)

        # we may get text port from YAML, convert to int
        self.port = try_int(port, self.SSH_PORT)
        self.pkey = self._get_pkey(pkey) if pkey else None
        self.password = password
        self.key_filename = key_filename
        self._client = False
        # paramiko loglevel debug will output ssh protocl debug
        # we don't ever really want that unless we are debugging paramiko
        # ssh issues
        if os.environ.get("PARAMIKO_DEBUG", "").lower() == "true":
            logging.getLogger("paramiko").setLevel(logging.DEBUG)
        else:
            logging.getLogger("paramiko").setLevel(logging.WARN)

    @classmethod
    def args_from_node(cls, node, overrides=None, defaults=None):
        if overrides is None:
            overrides = {}
        if defaults is None:
            defaults = {}

        params = ChainMap(overrides, node, defaults)
        return make_dict_from_map(params, cls.get_arg_key_map())

    @classmethod
    def from_node(cls, node, overrides=None, defaults=None):
        return cls(**cls.args_from_node(node, overrides, defaults))

    def _get_pkey(self, key):
        if isinstance(key, six.string_types):
            key = six.moves.StringIO(key)
        errors = []
        for key_class in (paramiko.rsakey.RSAKey, paramiko.dsskey.DSSKey):
            try:
                return key_class.from_private_key(key)
            except paramiko.SSHException as e:
                errors.append(e)
        raise exceptions.SSHError(error_msg='Invalid pkey: %s' % errors)

    @property
    def is_connected(self):
        return bool(self._client)

    def _get_client(self):
        if self.is_connected:
            return self._client
        try:
            self._client = paramiko.SSHClient()
            self._client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
            self._client.connect(self.host, username=self.user,
                                 port=self.port, pkey=self.pkey,
                                 key_filename=self.key_filename,
                                 password=self.password,
                                 allow_agent=False, look_for_keys=False,
                                 timeout=1)
            return self._client
        except Exception as e:
            message = ("Exception %(exception_type)s was raised "
                       "during connect. Exception value is: %(exception)r" %
                       {"exception": e, "exception_type": type(e)})
            self._client = False
            raise exceptions.SSHError(error_msg=message)

    def _make_dict(self):
        return {
            'user': self.user,
            'host': self.host,
            'port': self.port,
            'pkey': self.pkey,
            'key_filename': self.key_filename,
            'password': self.password,
            'name': self.name,
        }

    def copy(self):
        return self.get_class()(**self._make_dict())

    def close(self):
        if self._client:
            self._client.close()
            self._client = False

    def run(self, cmd, stdin=None, stdout=None, stderr=None,
            raise_on_error=True, timeout=3600,
            keep_stdin_open=False, pty=False):
        """Execute specified command on the server.

        :param cmd:             Command to be executed.
        :type cmd:              str
        :param stdin:           Open file or string to pass to stdin.
        :param stdout:          Open file to connect to stdout.
        :param stderr:          Open file to connect to stderr.
        :param raise_on_error:  If False then exit code will be return. If True
                                then exception will be raized if non-zero code.
        :param timeout:         Timeout in seconds for command execution.
                                Default 1 hour. No timeout if set to 0.
        :param keep_stdin_open: don't close stdin on empty reads
        :type keep_stdin_open:  bool
        :param pty:             Request a pseudo terminal for this connection.
                                This allows passing control characters.
                                Default False.
        :type pty:              bool
        """

        client = self._get_client()

        if isinstance(stdin, six.string_types):
            stdin = six.moves.StringIO(stdin)

        return self._run(client, cmd, stdin=stdin, stdout=stdout,
                         stderr=stderr, raise_on_error=raise_on_error,
                         timeout=timeout,
                         keep_stdin_open=keep_stdin_open, pty=pty)

    def _run(self, client, cmd, stdin=None, stdout=None, stderr=None,
             raise_on_error=True, timeout=3600,
             keep_stdin_open=False, pty=False):

        transport = client.get_transport()
        session = transport.open_session()
        if pty:
            session.get_pty()
        session.exec_command(cmd)
        start_time = time.time()

        # encode on transmit, decode on receive
        data_to_send = encodeutils.safe_encode("", incoming='utf-8')
        stderr_data = None

        # If we have data to be sent to stdin then `select' should also
        # check for stdin availability.
        if stdin and not stdin.closed:
            writes = [session]
        else:
            writes = []

        while True:
            # Block until data can be read/write.
            e = select.select([session], writes, [session], 1)[2]

            if session.recv_ready():
                data = encodeutils.safe_decode(session.recv(4096), 'utf-8')
                self.log.debug("stdout: %r", data)
                if stdout is not None:
                    stdout.write(data)
                continue

            if session.recv_stderr_ready():
                stderr_data = encodeutils.safe_decode(
                    session.recv_stderr(4096), 'utf-8')
                self.log.debug("stderr: %r", stderr_data)
                if stderr is not None:
                    stderr.write(stderr_data)
                continue

            if session.send_ready():
                if stdin is not None and not stdin.closed:
                    if not data_to_send:
                        stdin_txt = stdin.read(4096)
                        if stdin_txt is None:
                            stdin_txt = ''
                        data_to_send = encodeutils.safe_encode(
                            stdin_txt, incoming='utf-8')
                        if not data_to_send:
                            # we may need to keep stdin open
                            if not keep_stdin_open:
                                stdin.close()
                                session.shutdown_write()
                                writes = []
                    if data_to_send:
                        sent_bytes = session.send(data_to_send)
                        # LOG.debug("sent: %s" % data_to_send[:sent_bytes])
                        data_to_send = data_to_send[sent_bytes:]

            if session.exit_status_ready():
                break

            if timeout and (time.time() - timeout) > start_time:
                message = ('Timeout executing command %(cmd)s on host %(host)s'
                           % {"cmd": cmd, "host": self.host})
                raise exceptions.SSHTimeout(error_msg=message)
            if e:
                raise exceptions.SSHError(error_msg='Socket error')

        exit_status = session.recv_exit_status()
        if exit_status != 0 and raise_on_error:
            fmt = "Command '%(cmd)s' failed with exit_status %(status)d."
            details = fmt % {"cmd": cmd, "status": exit_status}
            if stderr_data:
                details += " Last stderr data: '%s'." % stderr_data
            LOG.critical("PROX ERROR: %s", details)
            raise exceptions.SSHError(error_msg=details)
        return exit_status

    def execute(self, cmd, stdin=None, timeout=3600, raise_on_error=False):
        """Execute the specified command on the server.

        :param cmd: (str)             Command to be executed.
        :param stdin: (StringIO)      Open file to be sent on process stdin.
        :param timeout: (int)         Timeout for execution of the command.
        :param raise_on_error: (bool) If True, then an SSHError will be raised
                                      when non-zero exit code.

        :returns: tuple (exit_status, stdout, stderr)
        """
        stdout = six.moves.StringIO()
        stderr = six.moves.StringIO()

        exit_status = self.run(cmd, stderr=stderr,
                               stdout=stdout, stdin=stdin,
                               timeout=timeout, raise_on_error=raise_on_error)
        stdout.seek(0)
        stderr.seek(0)
        return exit_status, stdout.read(), stderr.read()

    def wait(self, timeout=None, interval=1):
        """Wait for the host will be available via ssh."""
        if timeout is None:
            timeout = self.wait_timeout

        end_time = time.time() + timeout
        while True:
            try:
                return self.execute("uname")
            except (socket.error, exceptions.SSHError) as e:
                self.log.debug("Ssh is still unavailable: %r", e)
                time.sleep(interval)
            if time.time() > end_time:
                raise exceptions.SSHTimeout(
                    error_msg='Timeout waiting for "%s"' % self.host)

    def put(self, files, remote_path=b'.', recursive=False):
        client = self._get_client()

        with SCPClient(client.get_transport()) as scp:
            scp.put(files, remote_path, recursive)

    def get(self, remote_path, local_path='/tmp/', recursive=True):
        client = self._get_client()

        with SCPClient(client.get_transport()) as scp:
            scp.get(remote_path, local_path, recursive)

    # keep shell running in the background, e.g. screen
    def send_command(self, command):
        client = self._get_client()
        client.exec_command(command, get_pty=True)

    def _put_file_sftp(self, localpath, remotepath, mode=None):
        client = self._get_client()

        with client.open_sftp() as sftp:
            sftp.put(localpath, remotepath)
            if mode is None:
                mode = 0o777 & os.stat(localpath).st_mode
            sftp.chmod(remotepath, mode)

    TILDE_EXPANSIONS_RE = re.compile("(^~[^/]*/)?(.*)")

    def _put_file_shell(self, localpath, remotepath, mode=None):
        # quote to stop wordpslit
        tilde, remotepath = self.TILDE_EXPANSIONS_RE.match(remotepath).groups()
        if not tilde:
            tilde = ''
        cmd = ['cat > %s"%s"' % (tilde, remotepath)]
        if mode is not None:
            # use -- so no options
            cmd.append('chmod -- 0%o %s"%s"' % (mode, tilde, remotepath))

        with open(localpath, "rb") as localfile:
            # only chmod on successful cat
            self.run("&& ".join(cmd), stdin=localfile)

    def put_file(self, localpath, remotepath, mode=None):
        """Copy specified local file to the server.

        :param localpath:   Local filename.
        :param remotepath:  Remote filename.
        :param mode:        Permissions to set after upload
        """
        try:
            self._put_file_sftp(localpath, remotepath, mode=mode)
        except (paramiko.SSHException, socket.error):
            self._put_file_shell(localpath, remotepath, mode=mode)

    def provision_tool(self, tool_path, tool_file=None):
        return provision_tool(self, tool_path, tool_file)

    def put_file_obj(self, file_obj, remotepath, mode=None):
        client = self._get_client()

        with client.open_sftp() as sftp:
            sftp.putfo(file_obj, remotepath)
            if mode is not None:
                sftp.chmod(remotepath, mode)

    def get_file_obj(self, remotepath, file_obj):
        client = self._get_client()

        with client.open_sftp() as sftp:
            sftp.getfo(remotepath, file_obj)

    def interactive_terminal_open(self, time_out=45):
        """Open interactive terminal on a SSH channel.

        :param time_out: Timeout in seconds.
        :returns: SSH channel with opened terminal.

        .. warning:: Interruptingcow is used here, and it uses
           signal(SIGALRM) to let the operating system interrupt program
           execution. This has the following limitations: Python signal
           handlers only apply to the main thread, so you cannot use this
           from other threads. You must not use this in a program that
           uses SIGALRM itself (this includes certain profilers)
        """
        chan = self._get_client().get_transport().open_session()
        chan.get_pty()
        chan.invoke_shell()
        chan.settimeout(int(time_out))
        chan.set_combine_stderr(True)

        buf = ''
        while not buf.endswith((":~# ", ":~$ ", "~]$ ", "~]# ")):
            try:
                chunk = chan.recv(10 * 1024 * 1024)
                if not chunk:
                    break
                buf += chunk
                if chan.exit_status_ready():
                    self.log.error('Channel exit status ready')
                    break
            except socket.timeout:
                raise exceptions.SSHTimeout(error_msg='Socket timeout: %s' % buf)
        return chan

    def interactive_terminal_exec_command(self, chan, cmd, prompt):
        """Execute command on interactive terminal.

        interactive_terminal_open() method has to be called first!

        :param chan: SSH channel with opened terminal.
        :param cmd: Command to be executed.
        :param prompt: Command prompt, sequence of characters used to
        indicate readiness to accept commands.
        :returns: Command output.

        .. warning:: Interruptingcow is used here, and it uses
           signal(SIGALRM) to let the operating system interrupt program
           execution. This has the following limitations: Python signal
           handlers only apply to the main thread, so you cannot use this
           from other threads. You must not use this in a program that
           uses SIGALRM itself (this includes certain profilers)
        """
        chan.sendall('{c}\n'.format(c=cmd))
        buf = ''
        while not buf.endswith(prompt):
            try:
                chunk = chan.recv(10 * 1024 * 1024)
                if not chunk:
                    break
                buf += chunk
                if chan.exit_status_ready():
                    self.log.error('Channel exit status ready')
                    break
            except socket.timeout:
                message = ("Socket timeout during execution of command: "
                           "%(cmd)s\nBuffer content:\n%(buf)s" % {"cmd": cmd,
                                                                  "buf": buf})
                raise exceptions.SSHTimeout(error_msg=message)
        tmp = buf.replace(cmd.replace('\n', ''), '')
        for item in prompt:
            tmp.replace(item, '')
        return tmp

    @staticmethod
    def interactive_terminal_close(chan):
        """Close interactive terminal SSH channel.

        :param: chan: SSH channel to be closed.
        """
        chan.close()


class AutoConnectSSH(SSH):

    @classmethod
    def get_arg_key_map(cls):
        arg_key_map = super(AutoConnectSSH, cls).get_arg_key_map()
        arg_key_map['wait'] = ('wait', True)
        return arg_key_map

    # always wait or we will get OpenStack SSH errors
    def __init__(self, user, host, port=None, pkey=None,
                 key_filename=None, password=None, name=None, wait=True):
        super(AutoConnectSSH, self).__init__(user, host, port, pkey, key_filename, password, name)
        if wait and wait is not True:
            self.wait_timeout = int(wait)

    def _make_dict(self):
        data = super(AutoConnectSSH, self)._make_dict()
        data.update({
            'wait': self.wait_timeout
        })
        return data

    def _connect(self):
        if not self.is_connected:
            interval = 1
            timeout = self.wait_timeout

            end_time = time.time() + timeout
            while True:
                try:
                    return self._get_client()
                except (socket.error, exceptions.SSHError) as e:
                    self.log.debug("Ssh is still unavailable: %r", e)
                    time.sleep(interval)
                if time.time() > end_time:
                    raise exceptions.SSHTimeout(
                        error_msg='Timeout waiting for "%s"' % self.host)

    def drop_connection(self):
        """ Don't close anything, just force creation of a new client """
        self._client = False

    def execute(self, cmd, stdin=None, timeout=3600, raise_on_error=False):
        self._connect()
        return super(AutoConnectSSH, self).execute(cmd, stdin, timeout,
                                                   raise_on_error)

    def run(self, cmd, stdin=None, stdout=None, stderr=None,
            raise_on_error=True, timeout=3600,
            keep_stdin_open=False, pty=False):
        self._connect()
        return super(AutoConnectSSH, self).run(cmd, stdin, stdout, stderr, raise_on_error,
                                               timeout, keep_stdin_open, pty)

    def put(self, files, remote_path=b'.', recursive=False):
        self._connect()
        return super(AutoConnectSSH, self).put(files, remote_path, recursive)

    def put_file(self, local_path, remote_path, mode=None):
        self._connect()
        return super(AutoConnectSSH, self).put_file(local_path, remote_path, mode)

    def put_file_obj(self, file_obj, remote_path, mode=None):
        self._connect()
        return super(AutoConnectSSH, self).put_file_obj(file_obj, remote_path, mode)

    def get_file_obj(self, remote_path, file_obj):
        self._connect()
        return super(AutoConnectSSH, self).get_file_obj(remote_path, file_obj)

    def provision_tool(self, tool_path, tool_file=None):
        self._connect()
        return super(AutoConnectSSH, self).provision_tool(tool_path, tool_file)

    @staticmethod
    def get_class():
        # must return static class name, anything else refers to the calling class
        # i.e. the subclass, not the superclass
        return AutoConnectSSH