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
|
# Copyright (C) 2005 John Arbash-Meinel <john@arbash-meinel.com>
# Modified up by: Todd Whiteman <ToddW@ActiveState.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 distributed 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.
"""
Functions for communicating with Pageant, the basic windows ssh agent program.
"""
from __future__ import with_statement
import array
import ctypes.wintypes
import platform
import struct
try:
import _thread as thread # Python 3.x
except ImportError:
import thread # Python 2.5-2.7
from . import _winapi
_AGENT_COPYDATA_ID = 0x804e50ba
_AGENT_MAX_MSGLEN = 8192
# Note: The WM_COPYDATA value is pulled from win32con, as a workaround
# so we do not have to import this huge library just for this one variable.
win32con_WM_COPYDATA = 74
def _get_pageant_window_object():
return ctypes.windll.user32.FindWindowA('Pageant', 'Pageant')
def can_talk_to_agent():
"""
Check to see if there is a "Pageant" agent we can talk to.
This checks both if we have the required libraries (win32all or ctypes)
and if there is a Pageant currently running.
"""
return bool(_get_pageant_window_object())
ULONG_PTR = ctypes.c_uint64 if platform.architecture()[0] == '64bit' else ctypes.c_uint32
class COPYDATASTRUCT(ctypes.Structure):
"""
ctypes implementation of
http://msdn.microsoft.com/en-us/library/windows/desktop/ms649010%28v=vs.85%29.aspx
"""
_fields_ = [
('num_data', ULONG_PTR),
('data_size', ctypes.wintypes.DWORD),
('data_loc', ctypes.c_void_p),
]
def _query_pageant(msg):
"""
Communication with the Pageant process is done through a shared
memory-mapped file.
"""
hwnd = _get_pageant_window_object()
if not hwnd:
# Raise a failure to connect exception, pageant isn't running anymore!
return None
# create a name for the mmap
map_name = 'PageantRequest%08x' % thread.get_ident()
pymap = _winapi.MemoryMap(map_name, _AGENT_MAX_MSGLEN,
_winapi.get_security_attributes_for_user(),
)
with pymap:
pymap.write(msg)
# Create an array buffer containing the mapped filename
char_buffer = array.array("c", map_name + '\0')
char_buffer_address, char_buffer_size = char_buffer.buffer_info()
# Create a string to use for the SendMessage function call
cds = COPYDATASTRUCT(_AGENT_COPYDATA_ID, char_buffer_size,
char_buffer_address)
response = ctypes.windll.user32.SendMessageA(hwnd,
win32con_WM_COPYDATA, ctypes.sizeof(cds), ctypes.byref(cds))
if response > 0:
pymap.seek(0)
datalen = pymap.read(4)
retlen = struct.unpack('>I', datalen)[0]
return datalen + pymap.read(retlen)
return None
class PageantConnection(object):
"""
Mock "connection" to an agent which roughly approximates the behavior of
a unix local-domain socket (as used by Agent). Requests are sent to the
pageant daemon via special Windows magick, and responses are buffered back
for subsequent reads.
"""
def __init__(self):
self._response = None
def send(self, data):
self._response = _query_pageant(data)
def recv(self, n):
if self._response is None:
return ''
ret = self._response[:n]
self._response = self._response[n:]
if self._response == '':
self._response = None
return ret
def close(self):
pass
|