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
|
# Copyright (C) 2009-2016 by the Free Software Foundation, Inc.
#
# This file is part of GNU Mailman.
#
# GNU Mailman 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.
#
# GNU Mailman 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
# GNU Mailman. If not, see <http://www.gnu.org/licenses/>.
"""Fake MTA for testing purposes."""
import logging
from aiosmtpd.controller import Controller
from lazr.smtptest.controller import QueueController
from lazr.smtptest.server import Channel, QueueServer
from mailman import public
from mailman.interfaces.mta import IMailTransportAgentLifecycle
from queue import Empty, Queue
from zope.interface import implementer
log = logging.getLogger('lazr.smtptest')
@public
@implementer(IMailTransportAgentLifecycle)
class FakeMTA:
"""Fake MTA for testing purposes."""
def create(self, mlist):
pass
def delete(self, mlist):
pass
def regenerate(self, output=None):
pass
class StatisticsChannel(Channel):
"""A channel that can answers to the fake STAT command."""
def __init__(self, server, connection, address):
super().__init__(server, connection, address)
self._auth_response = None
self._waiting_for_auth_response = False
def smtp_EHLO(self, arg):
if not arg:
self.push('501 Syntax: HELO hostname')
return
if self._SMTPChannel__greeting:
self.push('503 Duplicate HELO/EHLO')
else:
self._SMTPChannel__greeting = arg
self.push('250-%s' % self._SMTPChannel__fqdn)
self.push('250 AUTH PLAIN')
def smtp_STAT(self, arg):
"""Cause the server to send statistics to its controller."""
self._server.send_statistics()
self.push('250 Ok')
def _check_auth(self, response):
# Base 64 for "testuser:testpass"
if response == 'AHRlc3R1c2VyAHRlc3RwYXNz':
self.push('235 Ok')
self._server.send_auth(response)
else:
self.push('571 Bad authentication')
def smtp_AUTH(self, arg):
"""Record that the AUTH occurred."""
args = arg.split()
if args[0].lower() == 'plain':
if len(args) == 2:
# The second argument is the AUTH PLAIN <initial-response>
# which must be equal to the base 64 equivalent of the
# expected login string "testuser:testpass".
self._check_auth(args[1])
else:
assert len(args) == 1, args
# Send a challenge and set us up to wait for the response.
self.push('334 ')
self._waiting_for_auth_response = True
else:
self.push('571 Bad authentication')
def smtp_RCPT(self, arg):
"""For testing, sometimes cause a non-25x response."""
code = self._server.next_error('rcpt')
if code is None:
# Everything's cool.
Channel.smtp_RCPT(self, arg)
else:
# The test suite wants this to fail. The message corresponds to
# the exception we expect smtplib.SMTP to raise.
self.push('%d Error: SMTPRecipientsRefused' % code)
def smtp_MAIL(self, arg):
"""For testing, sometimes cause a non-25x response."""
code = self._server.next_error('mail')
if code is None:
# Everything's cool.
Channel.smtp_MAIL(self, arg)
else:
# The test suite wants this to fail. The message corresponds to
# the exception we expect smtplib.SMTP to raise.
self.push('%d Error: SMTPResponseException' % code)
def found_terminator(self):
# Are we're waiting for the AUTH challenge response?
if self._waiting_for_auth_response:
line = self._emptystring.join(self.received_lines)
self._auth_response = line
self._waiting_for_auth_response = False
self.received_lines = []
# Now check to see if they authenticated correctly.
self._check_auth(line)
else:
super().found_terminator()
class ConnectionCountingServer(QueueServer):
"""Count the number of SMTP connections opened."""
def __init__(self, host, port, queue, oob_queue, err_queue):
"""See `lazr.smtptest.server.QueueServer`.
:param oob_queue: A queue for communicating information back to the
controller, e.g. statistics.
:type oob_queue: `Queue.Queue`
:param err_queue: A queue for allowing the controller to request SMTP
errors from the server.
:type err_queue: `Queue.Queue`
"""
QueueServer.__init__(self, host, port, queue)
self._connection_count = 0
self.last_auth = None
# The out-of-band queue is where the server sends statistics to the
# controller upon request.
self._oob_queue = oob_queue
self._err_queue = err_queue
self._last_error = None
def next_error(self, command):
"""Return the next error for the SMTP command, if there is one.
:param command: The SMTP command for which an error might be
expected. If the next error matches the given command, the
expected error code is returned.
:type command: string, lower-cased
:return: An SMTP error code
:rtype: integer
"""
# If the last error we pulled from the queue didn't match, then we're
# caching it, and it might match this expected error. If there is no
# last error in the cache, get one from the queue now.
if self._last_error is None:
try:
self._last_error = self._err_queue.get_nowait()
except Empty:
# No error is expected
return None
if self._last_error[0] == command:
code = self._last_error[1]
self._last_error = None
return code
return None
def handle_accept(self):
"""See `lazr.smtp.server.Server`."""
connection, address = self.accept()
self._connection_count += 1
log.info('[ConnectionCountingServer] accepted: %s', address)
StatisticsChannel(self, connection, address)
def process_message(self, peer, mailfrom, rcpttos, data):
# Provide a guaranteed order to recpttos.
QueueServer.process_message(
self, peer, mailfrom, sorted(rcpttos), data)
def reset(self):
"""See `lazr.smtp.server.Server`."""
QueueServer.reset(self)
self._connection_count = 0
def send_statistics(self):
"""Send the current connection statistics to the controller."""
# Do not count the connection caused by the STAT connect.
self._connection_count -= 1
self._oob_queue.put(self._connection_count)
def send_auth(self, arg):
"""Echo back the authentication data."""
self._oob_queue.put(arg)
class ConnectionCountingController(QueueController):
"""Count the number of SMTP connections opened."""
def __init__(self, host, port):
"""See `lazr.smtptest.controller.QueueController`."""
self.oob_queue = Queue()
self.err_queue = Queue()
QueueController.__init__(self, host, port)
def _make_server(self, host, port):
"""See `lazr.smtptest.controller.QueueController`."""
self.server = ConnectionCountingServer(
host, port, self.queue, self.oob_queue, self.err_queue)
def start(self):
"""See `lazr.smtptest.controller.QueueController`."""
QueueController.start(self)
# Reset the connection statistics, since the base class's start()
# method causes a connection to occur.
self.reset()
def get_connection_count(self):
"""Retrieve the number of connections.
:return: The number of connections to the server that have been made.
:rtype: integer
"""
smtpd = self._connect()
smtpd.docmd('STAT')
# An Empty exception will occur if the data isn't available in 10
# seconds. Let that propagate.
return self.oob_queue.get(block=True, timeout=10)
def get_authentication_credentials(self):
"""Retrieve the last authentication credentials."""
return self.oob_queue.get(block=True, timeout=10)
@property
def messages(self):
"""Return all the messages received by the SMTP server."""
yield from self
def clear(self):
"""Clear all the messages from the queue."""
list(self)
def reset(self):
smtpd = self._connect()
smtpd.docmd('RSET')
|