diff --git a/sshuttle/tests/test_firewall.py b/sshuttle/tests/test_firewall.py
index 540a5bf..10734d9 100644
--- a/sshuttle/tests/test_firewall.py
+++ b/sshuttle/tests/test_firewall.py
@@ -1,9 +1,5 @@
 from mock import Mock, patch, call
 import io
-import os
-import os.path
-import shutil
-import filecmp
 
 import sshuttle.firewall
 
@@ -19,27 +15,27 @@ NSLIST
 10,2404:6800:4004:80c::33
 PORTS 1024,1025,1026,1027
 GO 1
+HOST 1.2.3.3,existing
 """)
     stdout = Mock()
     return stdin, stdout
 
 
-@patch('sshuttle.firewall.HOSTSFILE', new='tmp/hosts')
-@patch('sshuttle.firewall.hostmap', new={
-    'myhost': '1.2.3.4',
-    'myotherhost': '1.2.3.5',
-})
-def test_rewrite_etc_hosts():
-    if not os.path.isdir("tmp"):
-        os.mkdir("tmp")
+def test_rewrite_etc_hosts(tmpdir):
+    orig_hosts = tmpdir.join("hosts.orig")
+    orig_hosts.write("1.2.3.3 existing\n")
 
-    with open("tmp/hosts.orig", "w") as f:
-        f.write("1.2.3.3 existing\n")
+    new_hosts = tmpdir.join("hosts")
+    orig_hosts.copy(new_hosts)
 
-    shutil.copyfile("tmp/hosts.orig", "tmp/hosts")
+    hostmap = {
+        'myhost': '1.2.3.4',
+        'myotherhost': '1.2.3.5',
+    }
+    with patch('sshuttle.firewall.HOSTSFILE', new=str(new_hosts)):
+        sshuttle.firewall.rewrite_etc_hosts(hostmap, 10)
 
-    sshuttle.firewall.rewrite_etc_hosts(10)
-    with open("tmp/hosts") as f:
+    with new_hosts.open() as f:
         line = f.readline()
         s = line.split()
         assert s == ['1.2.3.3', 'existing']
@@ -57,39 +53,37 @@ def test_rewrite_etc_hosts():
         line = f.readline()
         assert line == ""
 
-    sshuttle.firewall.restore_etc_hosts(10)
-    assert filecmp.cmp("tmp/hosts.orig", "tmp/hosts", shallow=False) is True
+    with patch('sshuttle.firewall.HOSTSFILE', new=str(new_hosts)):
+        sshuttle.firewall.restore_etc_hosts(10)
+    assert orig_hosts.computehash() == new_hosts.computehash()
 
 
-@patch('sshuttle.firewall.HOSTSFILE', new='tmp/hosts')
+@patch('sshuttle.firewall.rewrite_etc_hosts')
 @patch('sshuttle.firewall.setup_daemon')
 @patch('sshuttle.firewall.get_method')
-def test_main(mock_get_method, mock_setup_daemon):
+def test_main(mock_get_method, mock_setup_daemon, mock_rewrite_etc_hosts):
     stdin, stdout = setup_daemon()
     mock_setup_daemon.return_value = stdin, stdout
 
-    if not os.path.isdir("tmp"):
-        os.mkdir("tmp")
+    mock_get_method("not_auto").name = "test"
+    mock_get_method.reset_mock()
 
-    sshuttle.firewall.main("test", False)
+    sshuttle.firewall.main("not_auto", False)
 
-    with open("tmp/hosts") as f:
-        line = f.readline()
-        s = line.split()
-        assert s == ['1.2.3.3', 'existing']
+    assert mock_rewrite_etc_hosts.mock_calls == [
+        call({'1.2.3.3': 'existing'}, 1024),
+        call({}, 1024),
+    ]
 
-        line = f.readline()
-        assert line == ""
-
-    stdout.mock_calls == [
+    assert stdout.mock_calls == [
         call.write('READY test\n'),
         call.flush(),
         call.write('STARTED\n'),
         call.flush()
     ]
-    mock_setup_daemon.mock_calls == [call()]
-    mock_get_method.mock_calls == [
-        call('test'),
+    assert mock_setup_daemon.mock_calls == [call()]
+    assert mock_get_method.mock_calls == [
+        call('not_auto'),
         call().setup_firewall(
             1024, 1026,
             [(10, u'2404:6800:4004:80c::33')],
@@ -104,6 +98,7 @@ def test_main(mock_get_method, mock_setup_daemon):
             [(2, 24, False, u'1.2.3.0'), (2, 32, True, u'1.2.3.66')],
             True),
         call().setup_firewall()(),
+        call().setup_firewall()(),
         call().setup_firewall(1024, 0, [], 10, [], True),
         call().setup_firewall(1025, 0, [], 2, [], True),
     ]