From 0dc9280e94ced62ebe6f5206616540764d6afe2f Mon Sep 17 00:00:00 2001
From: Jacob Champion <jchampion@apache.org>
Date: Fri, 14 Jul 2017 22:30:17 +0000
Subject: [PATCH] CVE-2017-9788: add unit tests for get_digest_rec()

Including the module source is a dirty hack, but maybe the direct way is
best for now. More functional tests are still TODO.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/httpdunit@1801996 13f79535-47bb-0310-9956-ffa450edef68
---
 test/unit/mod_auth_digest.c | 107 ++++++++++++++++++++++++++++++++++++
 1 file changed, 107 insertions(+)
 create mode 100644 test/unit/mod_auth_digest.c

diff --git a/test/unit/mod_auth_digest.c b/test/unit/mod_auth_digest.c
new file mode 100644
index 0000000000..0d55b26269
--- /dev/null
+++ b/test/unit/mod_auth_digest.c
@@ -0,0 +1,107 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "../httpdunit.h"
+
+/* XXX This'll almost certainly cause headaches... Need a better way to test
+ * module helper functions.
+ *
+ * - What if the user doesn't want to, or can't, build mod_auth_digest?
+ * - How do we make sure the Makefile rebuilds us when the module changes?
+ */
+#include "../../modules/aaa/mod_auth_digest.c"
+
+/*
+ * Test Fixture -- runs once per test
+ */
+
+static apr_pool_t  *g_pool;
+static request_rec *g_request;
+
+/* XXX: duplicated from the authn.c tests; find a way to pull this into a helper
+ * library */
+static void mod_auth_digest_setup(void)
+{
+    if (apr_pool_create(&g_pool, NULL) != APR_SUCCESS) {
+        exit(1);
+    }
+
+    /* Stub out just enough of a request_req to get the tests working.
+     * Unfortunately this couples us to implementation details in the code being
+     * tested, but the logic to get a "real" request_rec requires spinning up
+     * half of the world. */
+    g_request = apr_pcalloc(g_pool, sizeof(*g_request));
+    if (!g_request) {
+        exit(1);
+    }
+
+    g_request->pool = g_pool;
+    g_request->headers_in = apr_table_make(g_pool, 1);
+
+    if (!g_request->headers_in) {
+        exit(1);
+    }
+}
+
+static void mod_auth_digest_teardown(void)
+{
+    apr_pool_destroy(g_pool);
+}
+
+/*
+ * get_digest_rec()
+ *
+ * Note that this function is an implementation detail, so the tests might not
+ * have the longest lifetime.
+ */
+
+/* TODO: more functional tests! */
+
+START_TEST(get_digest_rec_uses_empty_string_for_key_without_value)
+{
+    digest_header_rec resp = { 0 };
+    apr_table_set(g_request->headers_in, "Authorization",
+                  "Digest username=user, nc");
+
+    get_digest_rec(g_request, &resp);
+
+    ck_assert_str_eq(resp.username,    "user");
+    ck_assert_str_eq(resp.nonce_count, "");
+}
+END_TEST
+
+/*
+ * Regression test for CVE-2017-9788. Note that it only reliably fails if APR
+ * fills memory with something other than NULL; otherwise you can get false
+ * positives. But it's better than nothing.
+ */
+START_TEST(get_digest_rec_does_not_use_uninitialized_memory_for_key_without_value)
+{
+    digest_header_rec resp = { 0 };
+    apr_table_set(g_request->headers_in, "Authorization", "Digest nc");
+
+    get_digest_rec(g_request, &resp);
+
+    ck_assert_str_eq(resp.nonce_count, "");
+}
+END_TEST
+
+/*
+ * Test Case Boilerplate
+ */
+HTTPD_BEGIN_TEST_CASE_WITH_FIXTURE(mod_auth_digest, mod_auth_digest_setup, mod_auth_digest_teardown)
+#include "test/unit/mod_auth_digest.tests"
+HTTPD_END_TEST_CASE
-- 
2.40.0