root / ncclient / transport / ssh.py @ 7b02d55b
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1 | d095a59e | Shikhar Bhushan | # Copyright 2009 Shikhar Bhushan
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2 | d095a59e | Shikhar Bhushan | #
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3 | d095a59e | Shikhar Bhushan | # Licensed under the Apache License, Version 2.0 (the "License");
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4 | d095a59e | Shikhar Bhushan | # you may not use this file except in compliance with the License.
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5 | d095a59e | Shikhar Bhushan | # You may obtain a copy of the License at
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6 | d095a59e | Shikhar Bhushan | #
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7 | d095a59e | Shikhar Bhushan | # http://www.apache.org/licenses/LICENSE-2.0
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8 | d095a59e | Shikhar Bhushan | #
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9 | d095a59e | Shikhar Bhushan | # Unless required by applicable law or agreed to in writing, software
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10 | d095a59e | Shikhar Bhushan | # distributed under the License is distributed on an "AS IS" BASIS,
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11 | d095a59e | Shikhar Bhushan | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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12 | d095a59e | Shikhar Bhushan | # See the License for the specific language governing permissions and
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13 | d095a59e | Shikhar Bhushan | # limitations under the License.
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14 | d095a59e | Shikhar Bhushan | |
15 | d095a59e | Shikhar Bhushan | import os |
16 | d095a59e | Shikhar Bhushan | import socket |
17 | d095a59e | Shikhar Bhushan | from binascii import hexlify |
18 | d095a59e | Shikhar Bhushan | from cStringIO import StringIO |
19 | d095a59e | Shikhar Bhushan | from select import select |
20 | d095a59e | Shikhar Bhushan | |
21 | d095a59e | Shikhar Bhushan | import paramiko |
22 | d095a59e | Shikhar Bhushan | |
23 | c35cebbf | Shikhar Bhushan | from errors import AuthenticationError, SessionCloseError, SSHError, SSHUnknownHostError |
24 | d095a59e | Shikhar Bhushan | from session import Session |
25 | d095a59e | Shikhar Bhushan | |
26 | 41e2ed46 | Shikhar Bhushan | import logging |
27 | 41e2ed46 | Shikhar Bhushan | logger = logging.getLogger('ncclient.transport.ssh')
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28 | 41e2ed46 | Shikhar Bhushan | |
29 | d095a59e | Shikhar Bhushan | BUF_SIZE = 4096
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30 | d095a59e | Shikhar Bhushan | MSG_DELIM = ']]>]]>'
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31 | d095a59e | Shikhar Bhushan | TICK = 0.1
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32 | d095a59e | Shikhar Bhushan | |
33 | 4f650d54 | Shikhar Bhushan | def default_unknown_host_cb(host, key): |
34 | 4f650d54 | Shikhar Bhushan | """An `unknown host callback` returns :const:`True` if it finds the key
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35 | 4f650d54 | Shikhar Bhushan | acceptable, and :const:`False` if not.
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36 | 4f650d54 | Shikhar Bhushan |
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37 | 216bb34c | Shikhar Bhushan | This default callback always returns :const:`False`, which would lead to
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38 | 216bb34c | Shikhar Bhushan | :meth:`connect` raising a :exc:`SSHUnknownHost` exception.
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39 | 4f650d54 | Shikhar Bhushan |
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40 | 216bb34c | Shikhar Bhushan | Supply another valid callback if you need to verify the host key
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41 | 216bb34c | Shikhar Bhushan | programatically.
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42 | 216bb34c | Shikhar Bhushan |
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43 | 216bb34c | Shikhar Bhushan | :arg host: the host for whom key needs to be verified
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44 | 216bb34c | Shikhar Bhushan | :type host: string
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45 | 4f650d54 | Shikhar Bhushan |
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46 | 216bb34c | Shikhar Bhushan | :arg key: a hex string representing the host key fingerprint
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47 | 216bb34c | Shikhar Bhushan | :type key: string
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48 | 4f650d54 | Shikhar Bhushan | """
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49 | 4f650d54 | Shikhar Bhushan | return False |
50 | 4f650d54 | Shikhar Bhushan | |
51 | 4f650d54 | Shikhar Bhushan | |
52 | d095a59e | Shikhar Bhushan | class SSHSession(Session): |
53 | 4f650d54 | Shikhar Bhushan | |
54 | 4f650d54 | Shikhar Bhushan | "Implements a :rfc:`4742` NETCONF session over SSH."
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55 | 4f650d54 | Shikhar Bhushan | |
56 | 583c11f6 | Shikhar Bhushan | def __init__(self, capabilities): |
57 | 583c11f6 | Shikhar Bhushan | Session.__init__(self, capabilities)
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58 | d095a59e | Shikhar Bhushan | self._host_keys = paramiko.HostKeys()
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59 | d095a59e | Shikhar Bhushan | self._transport = None |
60 | d095a59e | Shikhar Bhushan | self._connected = False |
61 | d095a59e | Shikhar Bhushan | self._channel = None |
62 | d095a59e | Shikhar Bhushan | self._buffer = StringIO() # for incoming data |
63 | d095a59e | Shikhar Bhushan | # parsing-related, see _parse()
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64 | 4f650d54 | Shikhar Bhushan | self._parsing_state = 0 |
65 | d095a59e | Shikhar Bhushan | self._parsing_pos = 0 |
66 | 4f650d54 | Shikhar Bhushan | |
67 | d095a59e | Shikhar Bhushan | def _parse(self): |
68 | d095a59e | Shikhar Bhushan | '''Messages ae delimited by MSG_DELIM. The buffer could have grown by a
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69 | d095a59e | Shikhar Bhushan | maximum of BUF_SIZE bytes everytime this method is called. Retains state
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70 | 4f650d54 | Shikhar Bhushan | across method calls and if a byte has been read it will not be
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71 | 4f650d54 | Shikhar Bhushan | considered again. '''
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72 | d095a59e | Shikhar Bhushan | delim = MSG_DELIM |
73 | d095a59e | Shikhar Bhushan | n = len(delim) - 1 |
74 | d095a59e | Shikhar Bhushan | expect = self._parsing_state
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75 | d095a59e | Shikhar Bhushan | buf = self._buffer
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76 | d095a59e | Shikhar Bhushan | buf.seek(self._parsing_pos)
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77 | d095a59e | Shikhar Bhushan | while True: |
78 | d095a59e | Shikhar Bhushan | x = buf.read(1)
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79 | d095a59e | Shikhar Bhushan | if not x: # done reading |
80 | d095a59e | Shikhar Bhushan | break
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81 | d095a59e | Shikhar Bhushan | elif x == delim[expect]: # what we expected |
82 | d095a59e | Shikhar Bhushan | expect += 1 # expect the next delim char |
83 | d095a59e | Shikhar Bhushan | else:
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84 | d095a59e | Shikhar Bhushan | continue
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85 | d095a59e | Shikhar Bhushan | # loop till last delim char expected, break if other char encountered
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86 | d095a59e | Shikhar Bhushan | for i in range(expect, n): |
87 | d095a59e | Shikhar Bhushan | x = buf.read(1)
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88 | d095a59e | Shikhar Bhushan | if not x: # done reading |
89 | d095a59e | Shikhar Bhushan | break
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90 | d095a59e | Shikhar Bhushan | if x == delim[expect]: # what we expected |
91 | d095a59e | Shikhar Bhushan | expect += 1 # expect the next delim char |
92 | d095a59e | Shikhar Bhushan | else:
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93 | d095a59e | Shikhar Bhushan | expect = 0 # reset |
94 | d095a59e | Shikhar Bhushan | break
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95 | d095a59e | Shikhar Bhushan | else: # if we didn't break out of the loop, full delim was parsed |
96 | d095a59e | Shikhar Bhushan | msg_till = buf.tell() - n |
97 | d095a59e | Shikhar Bhushan | buf.seek(0)
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98 | 41e2ed46 | Shikhar Bhushan | logger.debug('parsed new message')
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99 | 41e2ed46 | Shikhar Bhushan | self._dispatch_message(buf.read(msg_till).strip())
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100 | d095a59e | Shikhar Bhushan | buf.seek(n+1, os.SEEK_CUR)
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101 | d095a59e | Shikhar Bhushan | rest = buf.read() |
102 | d095a59e | Shikhar Bhushan | buf = StringIO() |
103 | d095a59e | Shikhar Bhushan | buf.write(rest) |
104 | d095a59e | Shikhar Bhushan | buf.seek(0)
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105 | 4ba5e843 | Shikhar Bhushan | expect = 0
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106 | d095a59e | Shikhar Bhushan | self._buffer = buf
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107 | d095a59e | Shikhar Bhushan | self._parsing_state = expect
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108 | d095a59e | Shikhar Bhushan | self._parsing_pos = self._buffer.tell() |
109 | 4f650d54 | Shikhar Bhushan | |
110 | 216bb34c | Shikhar Bhushan | def load_known_hosts(self, filename=None): |
111 | 216bb34c | Shikhar Bhushan | """Load host keys from a :file:`known_hosts`-style file. Can be called multiple
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112 | 216bb34c | Shikhar Bhushan | times.
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113 | 216bb34c | Shikhar Bhushan |
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114 | 216bb34c | Shikhar Bhushan | If *filename* is not specified, looks in the default locations i.e.
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115 | 216bb34c | Shikhar Bhushan | :file:`~/.ssh/known_hosts` and :file:`~/ssh/known_hosts` for Windows.
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116 | 216bb34c | Shikhar Bhushan | """
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117 | d095a59e | Shikhar Bhushan | if filename is None: |
118 | d095a59e | Shikhar Bhushan | filename = os.path.expanduser('~/.ssh/known_hosts')
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119 | d095a59e | Shikhar Bhushan | try:
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120 | 216bb34c | Shikhar Bhushan | self._host_keys.load(filename)
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121 | d095a59e | Shikhar Bhushan | except IOError: |
122 | 4ba5e843 | Shikhar Bhushan | # for windows
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123 | 4ba5e843 | Shikhar Bhushan | filename = os.path.expanduser('~/ssh/known_hosts')
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124 | 4ba5e843 | Shikhar Bhushan | try:
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125 | 216bb34c | Shikhar Bhushan | self._host_keys.load(filename)
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126 | 4ba5e843 | Shikhar Bhushan | except IOError: |
127 | 4ba5e843 | Shikhar Bhushan | pass
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128 | 216bb34c | Shikhar Bhushan | else:
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129 | 216bb34c | Shikhar Bhushan | self._host_keys.load(filename)
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130 | 4f650d54 | Shikhar Bhushan | |
131 | d095a59e | Shikhar Bhushan | def close(self): |
132 | d095a59e | Shikhar Bhushan | if self._transport.is_active(): |
133 | d095a59e | Shikhar Bhushan | self._transport.close()
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134 | d095a59e | Shikhar Bhushan | self._connected = False |
135 | 4f650d54 | Shikhar Bhushan | |
136 | 583c11f6 | Shikhar Bhushan | def connect(self, host, port=830, timeout=None, |
137 | 4f650d54 | Shikhar Bhushan | unknown_host_cb=default_unknown_host_cb, |
138 | 4f650d54 | Shikhar Bhushan | username=None, password=None, |
139 | d095a59e | Shikhar Bhushan | key_filename=None, allow_agent=True, look_for_keys=True): |
140 | 4f650d54 | Shikhar Bhushan | """Connect via SSH and initialize the NETCONF session. First attempts
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141 | 4f650d54 | Shikhar Bhushan | the publickey authentication method and then password authentication.
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142 | 4f650d54 | Shikhar Bhushan |
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143 | 216bb34c | Shikhar Bhushan | To disable attemting publickey authentication altogether, call with
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144 | 216bb34c | Shikhar Bhushan | *allow_agent* and *look_for_keys* as :const:`False`. This may be needed
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145 | 216bb34c | Shikhar Bhushan | for Cisco devices which immediately disconnect on an incorrect
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146 | 216bb34c | Shikhar Bhushan | authentication attempt.
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147 | 4f650d54 | Shikhar Bhushan |
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148 | 4f650d54 | Shikhar Bhushan | :arg host: the hostname or IP address to connect to
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149 | 216bb34c | Shikhar Bhushan | :type host: `string`
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150 | 4f650d54 | Shikhar Bhushan |
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151 | 4f650d54 | Shikhar Bhushan | :arg port: by default 830, but some devices use the default SSH port of 22 so this may need to be specified
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152 | 216bb34c | Shikhar Bhushan | :type port: `int`
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153 | 4f650d54 | Shikhar Bhushan |
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154 | 4f650d54 | Shikhar Bhushan | :arg timeout: an optional timeout for the TCP handshake
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155 | 216bb34c | Shikhar Bhushan | :type timeout: `int`
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156 | 4f650d54 | Shikhar Bhushan |
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157 | 216bb34c | Shikhar Bhushan | :arg unknown_host_cb: called when a host key is not recognized
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158 | 216bb34c | Shikhar Bhushan | :type unknown_host_cb: see :meth:`signature <ssh.default_unknown_host_cb>`
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159 | 4f650d54 | Shikhar Bhushan |
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160 | 4f650d54 | Shikhar Bhushan | :arg username: the username to use for SSH authentication
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161 | 216bb34c | Shikhar Bhushan | :type username: `string`
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162 | 4f650d54 | Shikhar Bhushan |
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163 | 216bb34c | Shikhar Bhushan | :arg password: the password used if using password authentication, or the passphrase to use for unlocking keys that require it
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164 | 216bb34c | Shikhar Bhushan | :type password: `string`
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165 | 4f650d54 | Shikhar Bhushan |
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166 | 4f650d54 | Shikhar Bhushan | :arg key_filename: a filename where a the private key to be used can be found
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167 | 216bb34c | Shikhar Bhushan | :type key_filename: `string`
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168 | 4f650d54 | Shikhar Bhushan |
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169 | 4f650d54 | Shikhar Bhushan | :arg allow_agent: enables querying SSH agent (if found) for keys
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170 | 216bb34c | Shikhar Bhushan | :type allow_agent: `bool`
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171 | 4f650d54 | Shikhar Bhushan |
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172 | 4f650d54 | Shikhar Bhushan | :arg look_for_keys: enables looking in the usual locations for ssh keys (e.g. :file:`~/.ssh/id_*`)
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173 | 216bb34c | Shikhar Bhushan | :type look_for_keys: `bool`
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174 | 4f650d54 | Shikhar Bhushan | """
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175 | 4f650d54 | Shikhar Bhushan | |
176 | bb700ea5 | Shikhar Bhushan | if username is None: |
177 | bb700ea5 | Shikhar Bhushan | raise SSHError("No username specified") |
178 | 4f650d54 | Shikhar Bhushan | |
179 | bb700ea5 | Shikhar Bhushan | sock = None
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180 | bb700ea5 | Shikhar Bhushan | for res in socket.getaddrinfo(host, port, socket.AF_UNSPEC, socket.SOCK_STREAM): |
181 | bb700ea5 | Shikhar Bhushan | af, socktype, proto, canonname, sa = res |
182 | bb700ea5 | Shikhar Bhushan | try:
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183 | bb700ea5 | Shikhar Bhushan | sock = socket.socket(af, socktype, proto) |
184 | bb700ea5 | Shikhar Bhushan | sock.settimeout(timeout) |
185 | bb700ea5 | Shikhar Bhushan | except socket.error:
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186 | bb700ea5 | Shikhar Bhushan | continue
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187 | bb700ea5 | Shikhar Bhushan | try:
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188 | bb700ea5 | Shikhar Bhushan | sock.connect(sa) |
189 | bb700ea5 | Shikhar Bhushan | except socket.error:
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190 | bb700ea5 | Shikhar Bhushan | sock.close() |
191 | bb700ea5 | Shikhar Bhushan | continue
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192 | bb700ea5 | Shikhar Bhushan | break
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193 | d095a59e | Shikhar Bhushan | else:
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194 | bb700ea5 | Shikhar Bhushan | raise SSHError("Could not open socket") |
195 | bb700ea5 | Shikhar Bhushan | |
196 | d095a59e | Shikhar Bhushan | t = self._transport = paramiko.Transport(sock)
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197 | d095a59e | Shikhar Bhushan | t.set_log_channel(logger.name) |
198 | 4f650d54 | Shikhar Bhushan | |
199 | d095a59e | Shikhar Bhushan | try:
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200 | d095a59e | Shikhar Bhushan | t.start_client() |
201 | d095a59e | Shikhar Bhushan | except paramiko.SSHException:
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202 | d095a59e | Shikhar Bhushan | raise SSHError('Negotiation failed') |
203 | 4f650d54 | Shikhar Bhushan | |
204 | d095a59e | Shikhar Bhushan | # host key verification
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205 | d095a59e | Shikhar Bhushan | server_key = t.get_remote_server_key() |
206 | 216bb34c | Shikhar Bhushan | known_host = self._host_keys.check(host, server_key)
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207 | 216bb34c | Shikhar Bhushan | |
208 | 216bb34c | Shikhar Bhushan | fingerprint = hexlify(server_key.get_fingerprint()) |
209 | 4f650d54 | Shikhar Bhushan | |
210 | 216bb34c | Shikhar Bhushan | if not known_host and not unknown_host_cb(host, fingerprint): |
211 | 216bb34c | Shikhar Bhushan | raise SSHUnknownHostError(host, fingerprint)
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212 | 4f650d54 | Shikhar Bhushan | |
213 | d095a59e | Shikhar Bhushan | if key_filename is None: |
214 | d095a59e | Shikhar Bhushan | key_filenames = [] |
215 | d095a59e | Shikhar Bhushan | elif isinstance(key_filename, basestring): |
216 | d095a59e | Shikhar Bhushan | key_filenames = [ key_filename ] |
217 | d095a59e | Shikhar Bhushan | else:
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218 | d095a59e | Shikhar Bhushan | key_filenames = key_filename |
219 | 4f650d54 | Shikhar Bhushan | |
220 | d095a59e | Shikhar Bhushan | self._auth(username, password, key_filenames, allow_agent, look_for_keys)
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221 | 4f650d54 | Shikhar Bhushan | |
222 | d095a59e | Shikhar Bhushan | self._connected = True # there was no error authenticating |
223 | 4f650d54 | Shikhar Bhushan | |
224 | d095a59e | Shikhar Bhushan | c = self._channel = self._transport.open_session() |
225 | d095a59e | Shikhar Bhushan | c.set_name('netconf')
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226 | 41e2ed46 | Shikhar Bhushan | c.invoke_subsystem('netconf')
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227 | 4f650d54 | Shikhar Bhushan | |
228 | d095a59e | Shikhar Bhushan | self._post_connect()
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229 | 4f650d54 | Shikhar Bhushan | |
230 | d095a59e | Shikhar Bhushan | # on the lines of paramiko.SSHClient._auth()
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231 | d095a59e | Shikhar Bhushan | def _auth(self, username, password, key_filenames, allow_agent, |
232 | d095a59e | Shikhar Bhushan | look_for_keys): |
233 | d095a59e | Shikhar Bhushan | saved_exception = None
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234 | 4f650d54 | Shikhar Bhushan | |
235 | d095a59e | Shikhar Bhushan | for key_filename in key_filenames: |
236 | d095a59e | Shikhar Bhushan | for cls in (paramiko.RSAKey, paramiko.DSSKey): |
237 | d095a59e | Shikhar Bhushan | try:
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238 | d095a59e | Shikhar Bhushan | key = cls.from_private_key_file(key_filename, password) |
239 | d095a59e | Shikhar Bhushan | logger.debug('Trying key %s from %s' %
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240 | d095a59e | Shikhar Bhushan | (hexlify(key.get_fingerprint()), key_filename)) |
241 | d095a59e | Shikhar Bhushan | self._transport.auth_publickey(username, key)
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242 | d095a59e | Shikhar Bhushan | return
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243 | d095a59e | Shikhar Bhushan | except Exception as e: |
244 | d095a59e | Shikhar Bhushan | saved_exception = e |
245 | d095a59e | Shikhar Bhushan | logger.debug(e) |
246 | 4f650d54 | Shikhar Bhushan | |
247 | d095a59e | Shikhar Bhushan | if allow_agent:
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248 | d095a59e | Shikhar Bhushan | for key in paramiko.Agent().get_keys(): |
249 | d095a59e | Shikhar Bhushan | try:
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250 | d095a59e | Shikhar Bhushan | logger.debug('Trying SSH agent key %s' %
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251 | d095a59e | Shikhar Bhushan | hexlify(key.get_fingerprint())) |
252 | d095a59e | Shikhar Bhushan | self._transport.auth_publickey(username, key)
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253 | d095a59e | Shikhar Bhushan | return
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254 | d095a59e | Shikhar Bhushan | except Exception as e: |
255 | d095a59e | Shikhar Bhushan | saved_exception = e |
256 | d095a59e | Shikhar Bhushan | logger.debug(e) |
257 | 4f650d54 | Shikhar Bhushan | |
258 | d095a59e | Shikhar Bhushan | keyfiles = [] |
259 | d095a59e | Shikhar Bhushan | if look_for_keys:
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260 | d095a59e | Shikhar Bhushan | rsa_key = os.path.expanduser('~/.ssh/id_rsa')
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261 | d095a59e | Shikhar Bhushan | dsa_key = os.path.expanduser('~/.ssh/id_dsa')
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262 | d095a59e | Shikhar Bhushan | if os.path.isfile(rsa_key):
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263 | d095a59e | Shikhar Bhushan | keyfiles.append((paramiko.RSAKey, rsa_key)) |
264 | d095a59e | Shikhar Bhushan | if os.path.isfile(dsa_key):
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265 | d095a59e | Shikhar Bhushan | keyfiles.append((paramiko.DSSKey, dsa_key)) |
266 | d095a59e | Shikhar Bhushan | # look in ~/ssh/ for windows users:
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267 | d095a59e | Shikhar Bhushan | rsa_key = os.path.expanduser('~/ssh/id_rsa')
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268 | d095a59e | Shikhar Bhushan | dsa_key = os.path.expanduser('~/ssh/id_dsa')
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269 | d095a59e | Shikhar Bhushan | if os.path.isfile(rsa_key):
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270 | d095a59e | Shikhar Bhushan | keyfiles.append((paramiko.RSAKey, rsa_key)) |
271 | d095a59e | Shikhar Bhushan | if os.path.isfile(dsa_key):
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272 | d095a59e | Shikhar Bhushan | keyfiles.append((paramiko.DSSKey, dsa_key)) |
273 | 4f650d54 | Shikhar Bhushan | |
274 | d095a59e | Shikhar Bhushan | for cls, filename in keyfiles: |
275 | d095a59e | Shikhar Bhushan | try:
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276 | d095a59e | Shikhar Bhushan | key = cls.from_private_key_file(filename, password) |
277 | d095a59e | Shikhar Bhushan | logger.debug('Trying discovered key %s in %s' %
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278 | d095a59e | Shikhar Bhushan | (hexlify(key.get_fingerprint()), filename)) |
279 | d095a59e | Shikhar Bhushan | self._transport.auth_publickey(username, key)
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280 | d095a59e | Shikhar Bhushan | return
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281 | d095a59e | Shikhar Bhushan | except Exception as e: |
282 | d095a59e | Shikhar Bhushan | saved_exception = e |
283 | d095a59e | Shikhar Bhushan | logger.debug(e) |
284 | 4f650d54 | Shikhar Bhushan | |
285 | d095a59e | Shikhar Bhushan | if password is not None: |
286 | d095a59e | Shikhar Bhushan | try:
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287 | d095a59e | Shikhar Bhushan | self._transport.auth_password(username, password)
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288 | d095a59e | Shikhar Bhushan | return
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289 | d095a59e | Shikhar Bhushan | except Exception as e: |
290 | d095a59e | Shikhar Bhushan | saved_exception = e |
291 | d095a59e | Shikhar Bhushan | logger.debug(e) |
292 | 4f650d54 | Shikhar Bhushan | |
293 | d095a59e | Shikhar Bhushan | if saved_exception is not None: |
294 | 541247ba | Shikhar Bhushan | # need pep-3134 to do this right
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295 | a7cb58ce | Shikhar Bhushan | raise AuthenticationError(repr(saved_exception)) |
296 | 4f650d54 | Shikhar Bhushan | |
297 | a7cb58ce | Shikhar Bhushan | raise AuthenticationError('No authentication methods available') |
298 | 4f650d54 | Shikhar Bhushan | |
299 | d095a59e | Shikhar Bhushan | def run(self): |
300 | d095a59e | Shikhar Bhushan | chan = self._channel
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301 | d095a59e | Shikhar Bhushan | chan.setblocking(0)
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302 | d095a59e | Shikhar Bhushan | q = self._q
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303 | d095a59e | Shikhar Bhushan | try:
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304 | d095a59e | Shikhar Bhushan | while True: |
305 | d095a59e | Shikhar Bhushan | # select on a paramiko ssh channel object does not ever return
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306 | 4f650d54 | Shikhar Bhushan | # it in the writable list, so it channel's don't exactly emulate
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307 | d095a59e | Shikhar Bhushan | # the socket api
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308 | d095a59e | Shikhar Bhushan | r, w, e = select([chan], [], [], TICK) |
309 | d095a59e | Shikhar Bhushan | # will wakeup evey TICK seconds to check if something
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310 | d095a59e | Shikhar Bhushan | # to send, more if something to read (due to select returning
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311 | d095a59e | Shikhar Bhushan | # chan in readable list)
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312 | d095a59e | Shikhar Bhushan | if r:
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313 | d095a59e | Shikhar Bhushan | data = chan.recv(BUF_SIZE) |
314 | d095a59e | Shikhar Bhushan | if data:
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315 | d095a59e | Shikhar Bhushan | self._buffer.write(data)
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316 | d095a59e | Shikhar Bhushan | self._parse()
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317 | d095a59e | Shikhar Bhushan | else:
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318 | 94265508 | Shikhar Bhushan | raise SessionCloseError(self._buffer.getvalue()) |
319 | d095a59e | Shikhar Bhushan | if not q.empty() and chan.send_ready(): |
320 | 41e2ed46 | Shikhar Bhushan | logger.debug('sending message')
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321 | d095a59e | Shikhar Bhushan | data = q.get() + MSG_DELIM |
322 | d095a59e | Shikhar Bhushan | while data:
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323 | d095a59e | Shikhar Bhushan | n = chan.send(data) |
324 | d095a59e | Shikhar Bhushan | if n <= 0: |
325 | 94265508 | Shikhar Bhushan | raise SessionCloseError(self._buffer.getvalue(), data) |
326 | d095a59e | Shikhar Bhushan | data = data[n:] |
327 | d095a59e | Shikhar Bhushan | except Exception as e: |
328 | 564bee4f | Shikhar Bhushan | logger.debug('broke out of main loop, error=%r', e)
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329 | 1d540e60 | Shikhar Bhushan | self.close()
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330 | 564bee4f | Shikhar Bhushan | self._dispatch_error(e)
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331 | 4f650d54 | Shikhar Bhushan | |
332 | d095a59e | Shikhar Bhushan | @property
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333 | d095a59e | Shikhar Bhushan | def transport(self): |
334 | 216bb34c | Shikhar Bhushan | """Underlying `paramiko.Transport
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335 | 4f650d54 | Shikhar Bhushan | <http://www.lag.net/paramiko/docs/paramiko.Transport-class.html>`_
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336 | 4f650d54 | Shikhar Bhushan | object. This makes it possible to call methods like set_keepalive on it.
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337 | 4f650d54 | Shikhar Bhushan | """
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338 | d095a59e | Shikhar Bhushan | return self._transport |