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
|
""" This module allows you to probe a client for a file, which is then
added to the specification. On subsequent runs, the file will be
replaced on the client if it is missing; if it has changed on the
client, it can either be updated in the specification or replaced on
the client """
import os
import sys
import errno
import lxml.etree
import Bcfg2.Server
import Bcfg2.Server.Plugin
import Bcfg2.Server.FileMonitor
from Bcfg2.Compat import b64decode
#: The probe we send to clients to get the file data. Returns an XML
#: document describing the file and its metadata. We avoid returning
#: a non-0 error code on most errors, since that could halt client
#: execution.
PROBECODE = """#!/usr/bin/env python
import os
import sys
import pwd
import grp
import Bcfg2.Client.XML
try:
from Bcfg2.Compat import b64encode, oct_mode
except ImportError:
from base64 import b64encode
oct_mode = oct
path = "%s"
if not os.path.exists(path):
sys.stderr.write("%%s does not exist" %% path)
raise SystemExit(0)
try:
stat = os.stat(path)
except:
sys.stderr.write("Could not stat %%s: %%s" %% (path, sys.exc_info()[1]))
raise SystemExit(0)
data = Bcfg2.Client.XML.Element("ProbedFileData",
name=path,
owner=pwd.getpwuid(stat[4])[0],
group=grp.getgrgid(stat[5])[0],
mode=oct_mode(stat[0] & 4095))
try:
data.text = b64encode(open(path).read())
except:
sys.stderr.write("Could not read %%s: %%s" %% (path, sys.exc_info()[1]))
raise SystemExit(0)
print(Bcfg2.Client.XML.tostring(data, xml_declaration=False).decode('UTF-8'))
"""
class FileProbes(Bcfg2.Server.Plugin.Plugin,
Bcfg2.Server.Plugin.Probing):
""" This module allows you to probe a client for a file, which is then
added to the specification. On subsequent runs, the file will be
replaced on the client if it is missing; if it has changed on the
client, it can either be updated in the specification or replaced on
the client """
__author__ = 'chris.a.st.pierre@gmail.com'
def __init__(self, core):
Bcfg2.Server.Plugin.Plugin.__init__(self, core)
Bcfg2.Server.Plugin.Probing.__init__(self)
self.config = \
Bcfg2.Server.Plugin.StructFile(os.path.join(self.data,
'config.xml'),
should_monitor=True,
create=self.name)
self.entries = dict()
self.probes = dict()
def GetProbes(self, metadata):
"""Return a set of probes for execution on client."""
if metadata.hostname not in self.probes:
cfg = self.core.plugins['Cfg']
self.entries[metadata.hostname] = dict()
self.probes[metadata.hostname] = []
for entry in self.config.Match(metadata):
path = entry.get("name")
# do not probe for files that are already in Cfg and
# for which update is false; we can't possibly do
# anything with the data we get from such a probe
if (entry.get('update', 'false').lower() == "false" and
not cfg.has_generator(entry, metadata)):
continue
self.entries[metadata.hostname][path] = entry
probe = lxml.etree.Element('probe', name=path,
source=self.name,
interpreter="/usr/bin/env python")
probe.text = PROBECODE % path
self.probes[metadata.hostname].append(probe)
self.debug_log("Adding file probe for %s to %s" %
(path, metadata.hostname))
return self.probes[metadata.hostname]
def ReceiveData(self, metadata, datalist):
"""Receive data from probe."""
self.debug_log("Receiving file probe data from %s" % metadata.hostname)
for data in datalist:
if data.text is None:
self.logger.error("Got null response to %s file probe from %s"
% (data.get('name'), metadata.hostname))
else:
try:
self.write_data(
lxml.etree.XML(data.text,
parser=Bcfg2.Server.XMLParser),
metadata)
except lxml.etree.XMLSyntaxError:
# if we didn't get XML back from the probe, assume
# it's an error message
self.logger.error(data.text)
def write_data(self, data, metadata):
"""Write the probed file data to the bcfg2 specification."""
filename = data.get("name")
contents = b64decode(data.text)
entry = self.entries[metadata.hostname][filename]
cfg = self.core.plugins['Cfg']
specific = "%s.H_%s" % (os.path.basename(filename), metadata.hostname)
# we can't use os.path.join() for this because specific
# already has a leading /, which confuses os.path.join()
fileloc = os.path.join(cfg.data,
os.path.join(filename, specific).lstrip("/"))
create = False
try:
cfg.entries[filename].bind_entry(entry, metadata)
except (KeyError, Bcfg2.Server.Plugin.PluginExecutionError):
create = True
# get current entry data
if entry.text and entry.get("encoding") == "base64":
entrydata = b64decode(entry.text)
else:
entrydata = entry.text
if create:
self.logger.info("Writing new probed file %s" % fileloc)
self.write_file(fileloc, contents)
self.verify_file(filename, contents, metadata)
infoxml = os.path.join(cfg.data, filename.lstrip("/"), "info.xml")
self.write_infoxml(infoxml, data)
elif entrydata == contents:
self.debug_log("Existing %s contents match probed contents" %
filename)
return
elif (entry.get('update', 'false').lower() == "true"):
self.logger.info("Writing updated probed file %s" % fileloc)
self.write_file(fileloc, contents)
self.verify_file(filename, contents, metadata)
else:
self.logger.info("Skipping updated probed file %s" % fileloc)
return
def write_file(self, fileloc, contents):
""" Write the probed file to disk """
try:
os.makedirs(os.path.dirname(fileloc))
except OSError:
err = sys.exc_info()[1]
if err.errno == errno.EEXIST:
pass
else:
self.logger.error("Could not create parent directories for "
"%s: %s" % (fileloc, err))
return
try:
open(fileloc, 'wb').write(contents)
except IOError:
err = sys.exc_info()[1]
self.logger.error("Could not write %s: %s" % (fileloc, err))
return
def verify_file(self, filename, contents, metadata):
""" Service the FAM events queued up by the key generation so
the data structure entries will be available for binding.
NOTE: We wait for up to ten seconds. There is some potential
for race condition, because if the file monitor doesn't get
notified about the new key files in time, those entries won't
be available for binding. In practice, this seems "good
enough"."""
entry = self.entries[metadata.hostname][filename]
cfg = self.core.plugins['Cfg']
tries = 0
updated = False
while not updated:
if tries >= 10:
self.logger.error("%s still not registered" % filename)
return
Bcfg2.Server.FileMonitor.get_fam().handle_events_in_interval(1)
try:
cfg.entries[filename].bind_entry(entry, metadata)
except Bcfg2.Server.Plugin.PluginExecutionError:
tries += 1
continue
# get current entry data
if entry.get("encoding") == "base64":
entrydata = b64decode(entry.text)
else:
entrydata = entry.text
if entrydata == contents:
updated = True
tries += 1
def write_infoxml(self, infoxml, data):
""" write an info.xml for the file """
if os.path.exists(infoxml):
return
self.logger.info("Writing %s for %s" % (infoxml, data.get("name")))
default_mdata = Bcfg2.Server.Plugin.default_path_metadata()
info = lxml.etree.Element(
"Info",
owner=data.get("owner", default_mdata['owner']),
group=data.get("group", default_mdata['group']),
mode=data.get("mode", default_mdata['mode']))
root = lxml.etree.Element("FileInfo")
root.append(info)
try:
root.getroottree().write(infoxml, xml_declaration=False,
pretty_print=True)
except IOError:
err = sys.exc_info()[1]
self.logger.error("Could not write %s: %s" % (infoxml, err))
return
|
