CVE-2019-3870 tests: Extend smbd tests to check for umask being overwritten

[sfrench/samba-autobuild/.git] / python / samba / tests / smbd_base.py

diff --git a/python/samba/tests/smbd_base.py b/python/samba/tests/smbd_base.py
new file mode 100644 (file)
index 0000000..4e5c364
--- /dev/null
+++ b/python/samba/tests/smbd_base.py
@@ -0,0 +1,48 @@
+# Unix SMB/CIFS implementation. Common code for smbd python bindings tests
+# Copyright (C) Catalyst.Net Ltd 2019
+#
+# 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/>.
+#
+from samba.tests import TestCaseInTempDir
+import os
+
+TEST_UMASK = 0o022
+
+class SmbdBaseTests(TestCaseInTempDir):
+
+    def get_umask(self):
+        # we can only get the umask by setting it to something
+        curr_umask = os.umask(0)
+        # restore the old setting
+        os.umask(curr_umask)
+        return curr_umask
+
+    def setUp(self):
+        super(SmbdBaseTests, self).setUp()
+        self.orig_umask = self.get_umask()
+
+        # set an arbitrary umask - the underlying smbd code should override
+        # this, but it allows us to check if umask is left unset
+        os.umask(TEST_UMASK)
+
+    def tearDown(self):
+        # the current umask should be what we set it to earlier - if it's not,
+        # it indicates the code has changed it and not restored it
+        self.assertEqual(self.get_umask(), TEST_UMASK,
+                         "umask unexpectedly overridden by test")
+
+        # restore the original umask value (before we interferred with it)
+        os.umask(self.orig_umask)
+
+        super(SmbdBaseTests, self).tearDown()