[Chromoting] Factor out common code for pin hashing.

remoting/host/pin_hash_unittest.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <set>
+#include <string>
+
+#include "remoting/host/pin_hash.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace remoting {
+
+class PinHashTest : public testing::Test {
+};
+
+TEST_F(PinHashTest, KnownHashValue) {
+  std::string hash = MakeHostPinHash("Host ID", "1234");
+  ASSERT_EQ("hmac:bk6RVRFLpLO89mr4QPHSg8CemUUtI90r2F0VfvTmWLI=", hash);
+}
+
+TEST_F(PinHashTest, VerifyHostPinHash) {
+  std::string host_id1("Host ID 1");
+  std::string host_id2("Host ID 2");
+  std::string pin1("1234");
+  std::string pin2("4321");
+  ASSERT_TRUE(VerifyHostPinHash(MakeHostPinHash(host_id1, pin1),
+                                host_id1,
+                                pin1));
+  ASSERT_FALSE(VerifyHostPinHash(MakeHostPinHash(host_id1, pin1),
+                                 host_id2,
+                                 pin1));
+  ASSERT_FALSE(VerifyHostPinHash(MakeHostPinHash(host_id1, pin1),
+                                 host_id1,
+                                 pin2));
+}
+
+}  // namespace remoting