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
|
# Copyright (C) 2006-2007 Robey Pointer <robeypointer@gmail.com>
#
# This file is part of paramiko.
#
# Paramiko is free software; you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation; either version 2.1 of the License, or (at your option)
# any later version.
#
# Paramiko is distrubuted in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with Paramiko; if not, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
"""
L{SSHConfig}.
"""
import fnmatch
class SSHConfig (object):
"""
Representation of config information as stored in the format used by
OpenSSH. Queries can be made via L{lookup}. The format is described in
OpenSSH's C{ssh_config} man page. This class is provided primarily as a
convenience to posix users (since the OpenSSH format is a de-facto
standard on posix) but should work fine on Windows too.
@since: 1.6
"""
def __init__(self):
"""
Create a new OpenSSH config object.
"""
self._config = [ { 'host': '*' } ]
def parse(self, file_obj):
"""
Read an OpenSSH config from the given file object.
@param file_obj: a file-like object to read the config file from
@type file_obj: file
"""
configs = [self._config[0]]
for line in file_obj:
line = line.rstrip('\n').lstrip()
if (line == '') or (line[0] == '#'):
continue
if '=' in line:
key, value = line.split('=', 1)
key = key.strip().lower()
else:
# find first whitespace, and split there
i = 0
while (i < len(line)) and not line[i].isspace():
i += 1
if i == len(line):
raise Exception('Unparsable line: %r' % line)
key = line[:i].lower()
value = line[i:].lstrip()
if key == 'host':
del configs[:]
# the value may be multiple hosts, space-delimited
for host in value.split():
# do we have a pre-existing host config to append to?
matches = [c for c in self._config if c['host'] == host]
if len(matches) > 0:
configs.append(matches[0])
else:
config = { 'host': host }
self._config.append(config)
configs.append(config)
else:
for config in configs:
config[key] = value
def lookup(self, hostname):
"""
Return a dict of config options for a given hostname.
The host-matching rules of OpenSSH's C{ssh_config} man page are used,
which means that all configuration options from matching host
specifications are merged, with more specific hostmasks taking
precedence. In other words, if C{"Port"} is set under C{"Host *"}
and also C{"Host *.example.com"}, and the lookup is for
C{"ssh.example.com"}, then the port entry for C{"Host *.example.com"}
will win out.
The keys in the returned dict are all normalized to lowercase (look for
C{"port"}, not C{"Port"}. No other processing is done to the keys or
values.
@param hostname: the hostname to lookup
@type hostname: str
"""
matches = [x for x in self._config if fnmatch.fnmatch(hostname, x['host'])]
# sort in order of shortest match (usually '*') to longest
matches.sort(lambda x,y: cmp(len(x['host']), len(y['host'])))
ret = {}
for m in matches:
ret.update(m)
ret = self._expand_variables(ret, hostname)
del ret['host']
return ret
def _expand_variables(self, config, hostname ):
"""
Return a dict of config options with expanded substitutions
for a given hostname.
For the moment only expansion of the %h substitution in the
hostname config is supported.
@param config: the config for the hostname
@type hostname: dict
@param hostname: the hostname that the config belongs to
@type hostname: str
"""
#TODO: Add support for expansion of all substitution parameters
#TODO: see man ssh_config(5)
if 'hostname' in config:
config['hostname'] = config['hostname'].replace('%h',hostname)
else:
config['hostname'] = hostname
return config
|
