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
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
|
#!/usr/bin/env python
# Unix SMB/CIFS implementation.
# Copyright (C) Kai Blin <kai@samba.org> 2011
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
import os
import sys
import struct
import random
from samba import socket
import samba.ndr as ndr
import samba.dcerpc.dns as dns
from samba.tests import TestCase
class DNSTest(TestCase):
def errstr(self, errcode):
"Return a readable error code"
string_codes = [
"OK",
"FORMERR",
"SERVFAIL",
"NXDOMAIN",
"NOTIMP",
"REFUSED",
"YXDOMAIN",
"YXRRSET",
"NXRRSET",
"NOTAUTH",
"NOTZONE",
]
return string_codes[errcode]
def assert_dns_rcode_equals(self, packet, rcode):
"Helper function to check return code"
p_errcode = packet.operation & 0x000F
self.assertEquals(p_errcode, rcode, "Expected RCODE %s, got %s" % \
(self.errstr(rcode), self.errstr(p_errcode)))
def assert_dns_opcode_equals(self, packet, opcode):
"Helper function to check opcode"
p_opcode = packet.operation & 0x7800
self.assertEquals(p_opcode, opcode, "Expected OPCODE %s, got %s" % \
(opcode, p_opcode))
def make_name_packet(self, opcode, qid=None):
"Helper creating a dns.name_packet"
p = dns.name_packet()
if qid is None:
p.id = random.randint(0x0, 0xffff)
p.operation = opcode
p.questions = []
return p
def finish_name_packet(self, packet, questions):
"Helper to finalize a dns.name_packet"
packet.qdcount = len(questions)
packet.questions = questions
def make_name_question(self, name, qtype, qclass):
"Helper creating a dns.name_question"
q = dns.name_question()
q.name = name
q.question_type = qtype
q.question_class = qclass
return q
def get_dns_domain(self):
"Helper to get dns domain"
return os.getenv('REALM', 'example.com').lower()
def dns_transaction_udp(self, packet, host=os.getenv('DC_SERVER_IP')):
"send a DNS query and read the reply"
s = None
try:
send_packet = ndr.ndr_pack(packet)
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, 0)
s.connect((host, 53))
s.send(send_packet, 0)
recv_packet = s.recv(2048, 0)
return ndr.ndr_unpack(dns.name_packet, recv_packet)
finally:
if s is not None:
s.close()
def test_one_a_query(self):
"create a query packet containing one query record"
p = self.make_name_packet(dns.DNS_OPCODE_QUERY)
questions = []
name = "%s.%s" % (os.getenv('DC_SERVER'), self.get_dns_domain())
q = self.make_name_question(name, dns.DNS_QTYPE_A, dns.DNS_QCLASS_IN)
print "asking for ", q.name
questions.append(q)
self.finish_name_packet(p, questions)
response = self.dns_transaction_udp(p)
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_OK)
self.assert_dns_opcode_equals(response, dns.DNS_OPCODE_QUERY)
self.assertEquals(response.ancount, 1)
self.assertEquals(response.answers[0].rdata,
os.getenv('DC_SERVER_IP'))
def test_two_queries(self):
"create a query packet containing two query records"
p = self.make_name_packet(dns.DNS_OPCODE_QUERY)
questions = []
name = "%s.%s" % (os.getenv('DC_SERVER'), self.get_dns_domain())
q = self.make_name_question(name, dns.DNS_QTYPE_A, dns.DNS_QCLASS_IN)
questions.append(q)
name = "%s.%s" % ('bogusname', self.get_dns_domain())
q = self.make_name_question(name, dns.DNS_QTYPE_A, dns.DNS_QCLASS_IN)
questions.append(q)
self.finish_name_packet(p, questions)
response = self.dns_transaction_udp(p)
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_FORMERR)
def test_qtype_all_query(self):
"create a QTYPE_ALL query"
p = self.make_name_packet(dns.DNS_OPCODE_QUERY)
questions = []
name = "%s.%s" % (os.getenv('DC_SERVER'), self.get_dns_domain())
q = self.make_name_question(name, dns.DNS_QTYPE_ALL, dns.DNS_QCLASS_IN)
print "asking for ", q.name
questions.append(q)
self.finish_name_packet(p, questions)
response = self.dns_transaction_udp(p)
num_answers = 1
dc_ipv6 = os.getenv('DC_SERVER_IPV6')
if dc_ipv6 is not None:
num_answers += 1
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_OK)
self.assert_dns_opcode_equals(response, dns.DNS_OPCODE_QUERY)
self.assertEquals(response.ancount, num_answers)
self.assertEquals(response.answers[0].rdata,
os.getenv('DC_SERVER_IP'))
if dc_ipv6 is not None:
self.assertEquals(response.answers[1].rdata, dc_ipv6)
def test_qclass_none_query(self):
"create a QCLASS_NONE query"
p = self.make_name_packet(dns.DNS_OPCODE_QUERY)
questions = []
name = "%s.%s" % (os.getenv('DC_SERVER'), self.get_dns_domain())
q = self.make_name_question(name, dns.DNS_QTYPE_ALL, dns.DNS_QCLASS_NONE)
questions.append(q)
self.finish_name_packet(p, questions)
response = self.dns_transaction_udp(p)
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_NOTIMP)
# Only returns an authority section entry in BIND and Win DNS
# FIXME: Enable one Samba implements this feature
# def test_soa_hostname_query(self):
# "create a SOA query for a hostname"
# p = self.make_name_packet(dns.DNS_OPCODE_QUERY)
# questions = []
#
# name = "%s.%s" % (os.getenv('DC_SERVER'), self.get_dns_domain())
# q = self.make_name_question(name, dns.DNS_QTYPE_SOA, dns.DNS_QCLASS_IN)
# questions.append(q)
#
# self.finish_name_packet(p, questions)
# response = self.dns_transaction_udp(p)
# self.assert_dns_rcode_equals(response, dns.DNS_RCODE_OK)
# self.assert_dns_opcode_equals(response, dns.DNS_OPCODE_QUERY)
# # We don't get SOA records for single hosts
# self.assertEquals(response.ancount, 0)
def test_soa_domain_query(self):
"create a SOA query for a domain"
p = self.make_name_packet(dns.DNS_OPCODE_QUERY)
questions = []
name = self.get_dns_domain()
q = self.make_name_question(name, dns.DNS_QTYPE_SOA, dns.DNS_QCLASS_IN)
questions.append(q)
self.finish_name_packet(p, questions)
response = self.dns_transaction_udp(p)
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_OK)
self.assert_dns_opcode_equals(response, dns.DNS_OPCODE_QUERY)
self.assertEquals(response.ancount, 1)
def test_two_updates(self):
"create two update requests"
p = self.make_name_packet(dns.DNS_OPCODE_UPDATE)
updates = []
name = "%s.%s" % (os.getenv('DC_SERVER'), self.get_dns_domain())
u = self.make_name_question(name, dns.DNS_QTYPE_A, dns.DNS_QCLASS_IN)
updates.append(u)
name = self.get_dns_domain()
u = self.make_name_question(name, dns.DNS_QTYPE_A, dns.DNS_QCLASS_IN)
updates.append(u)
self.finish_name_packet(p, updates)
response = self.dns_transaction_udp(p)
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_FORMERR)
def test_update_wrong_qclass(self):
"create update with DNS_QCLASS_NONE"
p = self.make_name_packet(dns.DNS_OPCODE_UPDATE)
updates = []
name = self.get_dns_domain()
u = self.make_name_question(name, dns.DNS_QTYPE_A, dns.DNS_QCLASS_NONE)
updates.append(u)
self.finish_name_packet(p, updates)
response = self.dns_transaction_udp(p)
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_NOTIMP)
def test_update_prereq_with_non_null_ttl(self):
"test update with a non-null TTL"
p = self.make_name_packet(dns.DNS_OPCODE_UPDATE)
updates = []
name = self.get_dns_domain()
u = self.make_name_question(name, dns.DNS_QTYPE_SOA, dns.DNS_QCLASS_IN)
updates.append(u)
self.finish_name_packet(p, updates)
prereqs = []
r = dns.res_rec()
r.name = "%s.%s" % (os.getenv('DC_SERVER'), self.get_dns_domain())
r.rr_type = dns.DNS_QTYPE_TXT
r.rr_class = dns.DNS_QCLASS_NONE
r.ttl = 1
r.length = 0
prereqs.append(r)
p.ancount = len(prereqs)
p.answers = prereqs
response = self.dns_transaction_udp(p)
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_FORMERR)
# I'd love to test this one, but it segfaults. :)
# def test_update_prereq_with_non_null_length(self):
# "test update with a non-null length"
# p = self.make_name_packet(dns.DNS_OPCODE_UPDATE)
# updates = []
#
# name = self.get_dns_domain()
#
# u = self.make_name_question(name, dns.DNS_QTYPE_SOA, dns.DNS_QCLASS_IN)
# updates.append(u)
# self.finish_name_packet(p, updates)
#
# prereqs = []
# r = dns.res_rec()
# r.name = "%s.%s" % (os.getenv('DC_SERVER'), self.get_dns_domain())
# r.rr_type = dns.DNS_QTYPE_TXT
# r.rr_class = dns.DNS_QCLASS_ANY
# r.ttl = 0
# r.length = 1
# prereqs.append(r)
#
# p.ancount = len(prereqs)
# p.answers = prereqs
#
# response = self.dns_transaction_udp(p)
# self.assert_dns_rcode_equals(response, dns.DNS_RCODE_FORMERR)
def test_update_prereq_nonexisting_name(self):
"test update with a non-null TTL"
p = self.make_name_packet(dns.DNS_OPCODE_UPDATE)
updates = []
name = self.get_dns_domain()
u = self.make_name_question(name, dns.DNS_QTYPE_SOA, dns.DNS_QCLASS_IN)
updates.append(u)
self.finish_name_packet(p, updates)
prereqs = []
r = dns.res_rec()
r.name = "idontexist.%s" % self.get_dns_domain()
r.rr_type = dns.DNS_QTYPE_TXT
r.rr_class = dns.DNS_QCLASS_ANY
r.ttl = 0
r.length = 0
prereqs.append(r)
p.ancount = len(prereqs)
p.answers = prereqs
response = self.dns_transaction_udp(p)
self.assert_dns_rcode_equals(response, dns.DNS_RCODE_NXRRSET)
if __name__ == "__main__":
import unittest
unittest.main()
|
