Merge pull request #798 from mail-in-a-box/fail2banjails

add fail2ban jails for ownCloud, postfix submission, roundcube, and the Mail-in-a-Box management daemon

tests/fail2ban.py

@@ -0,0 +1,195 @@
+# Test that a box's fail2ban setting are working
+# correctly by attempting a bunch of failed logins.
+# Specify SSH login information the command line -
+# we use that to reset fail2ban after each test,
+# and we extract the hostname from that to open
+# connections to.
+######################################################################
+
+import sys, os, time, functools
+
+# parse command line
+
+if len(sys.argv) < 2:
+	print("Usage: tests/fail2ban.py user@hostname")
+	sys.exit(1)
+
+ssh_user, hostname = sys.argv[1].split("@", 1)
+
+# define some test types
+
+import socket
+socket.setdefaulttimeout(10)
+
+class IsBlocked(Exception):
+	"""Tests raise this exception when it appears that a fail2ban
+	jail is in effect, i.e. on a connection refused error."""
+	pass
+
+def smtp_test():
+	import smtplib
+
+	try:
+		server = smtplib.SMTP(hostname, 587)
+	except ConnectionRefusedError:
+		# looks like fail2ban worked
+		raise IsBlocked()
+	server.starttls()
+	server.ehlo_or_helo_if_needed()
+
+	try:
+		server.login("fakeuser", "fakepassword")
+		raise Exception("authentication didn't fail")
+	except smtplib.SMTPAuthenticationError:
+		# athentication should fail
+		pass
+
+	try:
+		server.quit()
+	except:
+		# ignore errors here
+		pass
+
+def imap_test():
+	import imaplib
+
+	try:
+		M = imaplib.IMAP4_SSL(hostname)
+	except ConnectionRefusedError:
+		# looks like fail2ban worked
+		raise IsBlocked()
+
+	try:
+		M.login("fakeuser", "fakepassword")
+		raise Exception("authentication didn't fail")
+	except imaplib.IMAP4.error:
+		# authentication should fail
+		pass
+	finally:
+		M.logout() # shuts down connection, has nothing to do with login()
+
+def http_test(url, expected_status, postdata=None, qsargs=None, auth=None):
+	import urllib.parse
+	import requests
+	from requests.auth import HTTPBasicAuth
+
+	# form request
+	url = urllib.parse.urljoin("https://" + hostname, url)
+	if qsargs: url += "?" + urllib.parse.urlencode(qsargs)
+	urlopen = requests.get if not postdata else requests.post
+
+	try:
+		# issue request
+		r = urlopen(
+			url,
+			auth=HTTPBasicAuth(*auth) if auth else None,
+			data=postdata,
+			headers={'User-Agent': 'Mail-in-a-Box fail2ban tester'},
+			timeout=8)
+	except requests.exceptions.ConnectTimeout as e:
+		raise IsBlocked()
+	except requests.exceptions.ConnectionError as e:
+		if "Connection refused" in str(e):
+			raise IsBlocked()
+		raise # some other unexpected condition
+
+	# return response status code
+	if r.status_code != expected_status:
+		r.raise_for_status() # anything but 200
+		raise IOError("Got unexpected status code %s." % r.status_code)
+
+# define how to run a test
+
+def restart_fail2ban_service(final=False):
+	# Log in over SSH to restart fail2ban.
+	command = "sudo fail2ban-client reload"
+	if not final:
+		# Stop recidive jails during testing.
+		command += " && sudo fail2ban-client stop recidive"
+	os.system("ssh %s@%s \"%s\"" % (ssh_user, hostname, command))
+
+def testfunc_runner(i, testfunc, *args):
+	print(i+1, end=" ", flush=True)
+	testfunc(*args)
+
+def run_test(testfunc, args, count, within_seconds, parallel):
+	# Run testfunc count times in within_seconds seconds (and actually
+	# within a little less time so we're sure we're under the limit).
+	#
+	# Because some services are slow, like IMAP, we can't necessarily
+	# run testfunc sequentially and still get to count requests within
+	# the required time. So we split the requests across threads.
+
+	import requests.exceptions
+	from multiprocessing import Pool
+
+	restart_fail2ban_service()
+
+	# Log.
+	print(testfunc.__name__, " ".join(str(a) for a in args), "...")
+
+	# Record the start time so we can know how to evenly space our
+	# calls to testfunc.
+	start_time = time.time()
+
+	with Pool(parallel) as p:
+		# Distribute the requests across the pool.
+		asyncresults = []
+		for i in range(count):
+			ar = p.apply_async(testfunc_runner, [i, testfunc] + list(args))
+			asyncresults.append(ar)
+
+		# Wait for all runs to finish.
+		p.close()
+		p.join()
+
+		# Check for errors.
+		for ar in asyncresults:
+			try:
+				ar.get()
+			except IsBlocked:
+				print("Test machine prematurely blocked!")
+				return False
+
+	# Did we make enough requests within the limit?
+	if (time.time()-start_time) > within_seconds:
+		raise Exception("Test failed to make %s requests in %d seconds." % (count, within_seconds))
+
+	# Wait a moment for the block to be put into place.
+	time.sleep(4)
+
+	# The next call should fail.
+	print("*", end=" ", flush=True)
+	try:
+		testfunc(*args)
+	except IsBlocked:
+		# Success -- this one is supposed to be refused.
+		print("blocked [OK]")
+		return True # OK
+
+	print("not blocked!")
+	return False
+
+######################################################################
+
+if __name__ == "__main__":
+	# run tests
+
+	# SMTP bans at 10 even though we say 20 in the config because we get
+	# doubled-up warnings in the logs, we'll let that be for now
+	run_test(smtp_test, [], 10, 30, 8)
+
+	# IMAP
+	run_test(imap_test, [], 20, 30, 4)
+
+	# Mail-in-a-Box control panel
+	run_test(http_test, ["/admin/me", 200], 20, 30, 1)
+
+	# Munin via the Mail-in-a-Box control panel
+	run_test(http_test, ["/admin/munin/", 401], 20, 30, 1)
+
+	# ownCloud
+	run_test(http_test, ["/cloud/remote.php/webdav", 401, None, None, ["aa", "aa"]], 20, 120, 1)
+
+	# restart fail2ban so that this client machine is no longer blocked
+	restart_fail2ban_service(final=True)