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
|
# Copyright 2008 The Tor Project, Inc. See LICENSE for licensing information.
import os
import sys
import tempfile
import random
try:
import json
except ImportError:
import simplejson as json
try:
import _winreg
except ImportError:
_winreg = None
import thandy.formats
import thandy.keys
import thandy.master_keys
def moveFile(fromLocation, toLocation):
"""Move the file from fromLocation to toLocation, removing any file
in toLocation.
"""
if sys.platform in ('cygwin', 'win32'):
# Win32 doesn't let rename replace an existing file.
try:
os.unlink(toLocation)
except OSError:
pass
os.rename(fromLocation, toLocation)
def replaceFile(fname, contents, textMode=False):
"""overwrite the file in 'fname' atomically with the content of 'contents'
"""
dir, prefix = os.path.split(fname)
fd, fname_tmp = tempfile.mkstemp(prefix=prefix, dir=dir, text=textMode)
try:
os.write(fd, contents)
finally:
os.close(fd)
moveFile(fname_tmp, fname)
def userFilename(name):
try:
base = os.environ["THANDY_HOME"]
except KeyError:
base = "~/.thandy"
base = os.path.expanduser(base)
if not os.path.exists(base):
os.makedirs(base, 0700)
return os.path.normpath(os.path.join(base, name))
def ensureParentDir(name):
"""DOCDOC"""
directory = os.path.split(name)[0]
if not os.path.exists(directory):
os.makedirs(directory, 0700)
def getKeylist(keys_fname, checkKeys=True):
import thandy.master_keys
keydb = thandy.formats.Keylist()
for key in thandy.master_keys.MASTER_KEYS:
keydb.addKey(thandy.keys.RSAKey.fromJSon(key))
user_keys = userFilename("preload_keys")
if os.path.exists(user_keys):
#XXXX somewhat roundabout.
keylist = thandy.formats.makeKeylistObj(user_keys)
keydb.addFromKeylist(keylist, allowMasterKeys=True)
if keys_fname and os.path.exists(keys_fname):
f = open(keys_fname, 'r')
try:
obj = json.load(f)
finally:
f.close()
ss, role, path = thandy.formats.checkSignedObj(obj, keydb)
if role != 'master':
raise thandy.FormatException("%s wasn't a keylist."%keys_fname)
if checkKeys and not ss.isValid():
raise thandy.FormatException("%s not signed by enough master keys"%
keys_fname)
keydb.addFromKeylist(obj['signed'], allowMasterKeys=False)
return keydb
def randChooseWeighted(lst):
"""Given a list of (weight,item) tuples, pick an item with
probability proportional to its weight.
"""
totalweight = sum(w for w,i in lst)
position = random.uniform(0, totalweight)
soFar = 0
# We could use bisect here, but this is not going to be in the
# critical path. If it is, oops.
for w,i in lst:
soFar += w
if position < soFar:
return i
return lst[-1][1]
class NoRegistry(thandy.Exception):
pass
def getRegistryValue(keyname):
"""Read the contents of a Windows registry key from a given base."""
if _winreg is None:
raise NoRegistry()
hkey, rest = keyname.split("\\", 1)
key, value = rest.rsplit("\\", 1)
if not hkey.startswith("HKEY_"):
return None
base = getattr(_winreg, hkey)
settings = None
try:
try:
settings = _winreg.OpenKey(base, key)
return _winreg.QueryValueEx(settings, value)[0]
except (WindowsError, ValueError, TypeError):
return None
finally:
if settings is not None:
settings.Close()
|