Remove usage reports upon factory reset of device.

(This is a merge of http://go/wvgerrit/16162)

Usage tables on L3 devices are stored under IDM*. They will be removed
upon factory reset. However, we need to call OEMCrypto_DeleteUsageTable
for L1 devices because the usage tables are stored in secure storage.

bug: 25597957
Change-Id: I8533dfac60fad6ce7ddfd026a283633d6875dcf3

libwvdrmengine/cdm/core/include/cdm_engine.h

@@ -173,6 +173,7 @@ class CdmEngine {
 
  private:
   // private methods
+  void DeleteAllUsageReportsUponFactoryReset();
   bool ValidateKeySystem(const CdmKeySystem& key_system);
   CdmResponseType GetUsageInfo(const std::string& app_id,
                                SecurityLevel requested_security_level,

libwvdrmengine/cdm/core/src/cdm_engine.cpp

@@ -10,6 +10,7 @@
 #include "cdm_session.h"
 #include "clock.h"
 #include "device_files.h"
+#include "file_store.h"
 #include "license_protocol.pb.h"
 #include "log.h"
 #include "properties.h"
@@ -299,12 +300,18 @@ CdmResponseType CdmEngine::AddKey(const CdmSessionId& session_id,
 
   CdmResponseType sts = iter->second->AddKey(key_data, key_set_id);
 
-  if (KEY_ADDED != sts) {
+  switch (sts) {
-    LOGE("CdmEngine::AddKey: keys not added, result = %d", sts);
+    case KEY_ADDED:
-    return sts;
+      break;
+    case NEED_KEY:
+      LOGI("CdmEngine::AddKey: service certificate loaded, no key added");
+      break;
+    default:
+      LOGE("CdmEngine::AddKey: keys not added, result = %d", sts);
+      break;
   }
 
-  return KEY_ADDED;
+  return sts;
 }
 
 CdmResponseType CdmEngine::RestoreKey(const CdmSessionId& session_id,
@@ -332,7 +339,7 @@ CdmResponseType CdmEngine::RestoreKey(const CdmSessionId& session_id,
   if (sts != KEY_ADDED && sts != GET_RELEASED_LICENSE_ERROR) {
     LOGE("CdmEngine::RestoreKey: restore offline session failed = %d", sts);
   }
-  return sts;  // TODO ewew
+  return sts;
 }
 
 CdmResponseType CdmEngine::RemoveKeys(const CdmSessionId& session_id) {
@@ -596,6 +603,9 @@ CdmResponseType CdmEngine::GetProvisioningRequest(
     LOGE("CdmEngine::GetProvisioningRequest: invalid output parameters");
     return INVALID_PROVISIONING_REQUEST_PARAM_2;
   }
+
+  DeleteAllUsageReportsUponFactoryReset();
+
   if (NULL == cert_provisioning_.get()) {
     cert_provisioning_.reset(new CertificateProvisioning());
   }
@@ -657,6 +667,7 @@ CdmResponseType CdmEngine::HandleProvisioningResponse(
     }
     return NO_ERROR;
   }
+
   CdmResponseType ret = cert_provisioning_->HandleProvisioningResponse(
       origin, response, cert, wrapped_key);
   // Release resources only on success. It is possible that a provisioning
@@ -1091,4 +1102,34 @@ std::string CdmEngine::MapHdcpVersion(
   return "";
 }
 
+void CdmEngine::DeleteAllUsageReportsUponFactoryReset() {
+  std::string device_base_path_level1 = "";
+  std::string device_base_path_level3 = "";
+  Properties::GetDeviceFilesBasePath(kSecurityLevelL1,
+                                     &device_base_path_level1);
+  Properties::GetDeviceFilesBasePath(kSecurityLevelL3,
+                                     &device_base_path_level3);
+
+  File file;
+  if (!file.Exists(device_base_path_level1) &&
+      !file.Exists(device_base_path_level3)) {
+    scoped_ptr<CryptoSession> crypto_session(new CryptoSession());
+    CdmResponseType status = crypto_session->Open(
+        cert_provisioning_requested_security_level_);
+    if (NO_ERROR == status) {
+      status = crypto_session->DeleteAllUsageReports();
+      if (NO_ERROR != status) {
+        LOGW(
+            "CdmEngine::GetProvisioningRequest: "
+            "Fails to delete usage reports: %d", status);
+      }
+    } else {
+      LOGW(
+          "CdmEngine::GetProvisioningRequest: "
+          "Fails to open crypto session: error=%d.\n"
+          "Usage reports are not removed after factory reset.", status);
+    }
+  }
+}
+
 }  // namespace wvcdm

libwvdrmengine/cdm/core/src/oemcrypto_adapter_dynamic.cpp

@@ -226,7 +226,7 @@ struct LevelSession {
 // the dynamically loaded level 1 oemcrypto.  When initialized, it tries to
 // load the level 1 library and verifies that all needed functions are present.
 // If they are not, then it flags the level 1 as invalid.  Later, when the
-// function get(kLevel3) is called, if returns the level 3 function pointers.
+// function get(kLevel3) is called, it returns the level 3 function pointers.
 // When get(kLevelDefault) is called, it returns level 1 function pointers if
 // level 1 is valid and otherwise returns the level 3 function pointers.
 class Adapter {