Improve OEMCrypto unit tests

This is a merge of http://go/wvgerrit/13701 and http://go/wvgerrit/13780.

I added a new set of engine properties for the mock oemcrypto.  This
set pretends to be level 1. This allows the widevine build bot to test
the dual security level path: a level 1 liboemcrypto.so and a fall
back to L3.

I also adjusted the failing test in oemcrypto_test.cpp.  A correct fix
requires us to rewrite some of the oemcrypto mock code so that it
returns real error codes instead of just 'false' on error.

Change-Id: I9cdbfc23c87ad2fb6068eac1394ce4c5b6a32dae

libwvdrmengine/oemcrypto/mock/src/oemcrypto_engine_device_properties.cpp

@@ -39,4 +39,10 @@ bool CryptoEngine::is_anti_rollback_hw_present() {
   return false;
 }
 
+// Returns "L3" for a software only library.  L1 is for hardware protected
+// data paths.
+const char* CryptoEngine::security_level() {
+  return "L3";
+}
+
 }  // namespace wvoec_mock

libwvdrmengine/oemcrypto/mock/src/oemcrypto_engine_device_properties_L1.cpp

@@ -0,0 +1,49 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+//  Mock implementation of OEMCrypto APIs
+//
+//  This file contains oemcrypto engine properties that would be for a
+//  level 1 device.
+#include "oemcrypto_engine_mock.h"
+
+namespace wvoec_mock {
+
+// If local_display() returns true, we pretend we are using a built-in display,
+// instead of HDMI or WiFi output.
+bool CryptoEngine::local_display() {
+  return true;
+}
+
+// A closed platform is permitted to use clear buffers.
+bool CryptoEngine::closed_platform() {
+  return false;
+}
+
+// Returns the HDCP version currently in use.
+OEMCrypto_HDCP_Capability CryptoEngine::current_hdcp_capability() {
+  return local_display() ? HDCP_NO_DIGITAL_OUTPUT : HDCP_V1;
+}
+
+// Returns the max HDCP version supported.
+OEMCrypto_HDCP_Capability CryptoEngine::maximum_hdcp_capability() {
+  return HDCP_NO_DIGITAL_OUTPUT;
+}
+
+// Returns true if the client supports persistent storage of
+// offline usage table information.
+bool CryptoEngine::supports_storage() {
+  return true;
+}
+
+// Returns true to indicate the client does support anti-rollback hardware.
+bool CryptoEngine::is_anti_rollback_hw_present() {
+  return true;
+}
+
+// Returns "L3" for a software only library.  L1 is for hardware protected
+// data paths.
+const char* CryptoEngine::security_level() {
+  return "L1";
+}
+
+}  // namespace wvoec_mock

libwvdrmengine/oemcrypto/mock/src/oemcrypto_engine_mock.h

@@ -257,6 +257,7 @@ class CryptoEngine {
   bool closed_platform();
   bool supports_storage();
   bool is_anti_rollback_hw_present();
+  const char* security_level();
 
  private:
   SessionContext* current_session_;

libwvdrmengine/oemcrypto/mock/src/oemcrypto_mock.cpp

@@ -1001,7 +1001,11 @@ uint32_t OEMCrypto_APIVersion() {
 
 extern "C"
 const char* OEMCrypto_SecurityLevel() {
-  return "L3";
+  const char* security_level = crypto_engine->security_level();
+  if (LogCategoryEnabled(kLoggingTraceOEMCryptoCalls)) {
+    LOGI("-- bool OEMCrypto_SecurityLevel(); // returns %s.\n", security_level);
+  }
+  return security_level;
 }
 
 extern "C"

libwvdrmengine/oemcrypto/test/oemcrypto_test.cpp

@@ -1593,23 +1593,6 @@ class OEMCryptoClientTest : public ::testing::Test {
   }
 };
 
-TEST_F(OEMCryptoClientTest, AntiRollbackHardwareRequired) {
-  Session s;
-  s.open();
-  s.GenerateDerivedKeys();
-  s.FillSimpleMessage(0, wvoec_mock::kControlRequireAntiRollbackHardware, 0);
-  s.EncryptAndSign();
-  OEMCryptoResult sts = OEMCrypto_LoadKeys(
-      s.session_id(), s.message_ptr(), sizeof(MessageData), &s.signature()[0],
-      s.signature().size(), s.encrypted_license().mac_key_iv,
-      s.encrypted_license().mac_keys, kNumKeys, s.key_array(), NULL, 0);
-  if (OEMCrypto_IsAntiRollbackHwPresent()) {
-    ASSERT_EQ(OEMCrypto_SUCCESS, sts);
-  } else {
-    ASSERT_EQ(OEMCrypto_ERROR_UNKNOWN_FAILURE, sts);
-  }
-}
-
 //
 // Keybox Tests
 // These two tests are first, becuase it might give an idea why other
@@ -2347,6 +2330,23 @@ TEST_F(DISABLED_TestKeybox, LoadKeysWithNoDerivedKeys) {
   ASSERT_NE(OEMCrypto_SUCCESS, sts);
 }
 
+TEST_F(DISABLED_TestKeybox, AntiRollbackHardwareRequired) {
+  Session s;
+  s.open();
+  s.GenerateDerivedKeys();
+  s.FillSimpleMessage(0, wvoec_mock::kControlRequireAntiRollbackHardware, 0);
+  s.EncryptAndSign();
+  OEMCryptoResult sts = OEMCrypto_LoadKeys(
+      s.session_id(), s.message_ptr(), sizeof(MessageData), &s.signature()[0],
+      s.signature().size(), s.encrypted_license().mac_key_iv,
+      s.encrypted_license().mac_keys, kNumKeys, s.key_array(), NULL, 0);
+  if (OEMCrypto_IsAntiRollbackHwPresent()) {
+    ASSERT_EQ(OEMCrypto_SUCCESS, sts);
+  } else {
+    ASSERT_EQ(OEMCrypto_ERROR_UNKNOWN_FAILURE, sts);
+  }
+}
+
 class DISABLED_DecryptWithHDCP : public DISABLED_TestKeybox,
                                  public WithParamInterface<int> {
  public: