Allow Apps to Voluntarily Downgrade to L3 Crypto

This merges the following changes from the Widevine CDM repository:

564f4cc  Add CdmClientPropertySet to CDM
  Adds an interface to the CDM that allows it to query its client for
  certain properties.  In this case, this includes the ability to
  specify what security level is desired, as well as support for
  service ceritifcate privacy mode.

9cfbd3e  Force Level 3 fallback
  Adds support for voluntarily invoking L3 crypto to the OEMCrypto
  wrapper.

95d12c1  Add pointer to CdmClientPropertySet class to OpenSession.
  Adds support for storing the property set on a session-by-session
  basis and choosing the appropriate crypto level.

17de442  Add Settable Properties for Clank to Android
  Adds support for setting the aforementioned properties to the
  DrmEngine

bbe704d  Fixes to force fallback to level three security
  Corrections to invoke provisioning, OEMCrypto API with configured
  security level rather than the default. Unit tests were also revised.

Note that some parts of this are also support for the ability to use
a service certificate-based privacy mode. The remaining code for
supporting this mode is still forthcoming.

Bug: 10109249
Change-Id: I2755e4dea1de3e8a56cff237360298f7b7f1bddc

libwvdrmengine/cdm/core/src/properties.cpp

@@ -1,11 +1,10 @@
 // Copyright 2013 Google Inc. All Rights Reserved.
 
-#include "properties.h"
+#include "log.h"
 #include "properties_configuration.h"
 #include "wv_cdm_constants.h"
 
 namespace wvcdm {
-
 bool Properties::begin_license_usage_when_received_;
 bool Properties::require_explicit_renew_request_;
 bool Properties::oem_crypto_use_secure_buffers_;
@@ -13,6 +12,8 @@ bool Properties::oem_crypto_use_fifo_;
 bool Properties::oem_crypto_use_userspace_buffers_;
 bool Properties::use_certificates_as_identification_;
 bool Properties::extract_pssh_data_;
+bool Properties::decrypt_with_empty_session_support_;
+scoped_ptr<CdmClientPropertySetMap> Properties::session_property_set_;
 
 void Properties::Init() {
   begin_license_usage_when_received_ = kPropertyBeginLicenseUsageWhenReceived;
@@ -23,6 +24,73 @@ void Properties::Init() {
   use_certificates_as_identification_ =
       kPropertyUseCertificatesAsIdentification;
   extract_pssh_data_ = kExtractPsshData;
+  decrypt_with_empty_session_support_ = kDecryptWithEmptySessionSupport;
+  session_property_set_.reset(new CdmClientPropertySetMap());
 }
 
+bool Properties::AddSessionPropertySet(
+    const CdmSessionId& session_id,
+    const CdmClientPropertySet* property_set) {
+  if (NULL == session_property_set_.get()) {
+    return false;
+  }
+  std::pair<CdmClientPropertySetMap::iterator, bool> result =
+    session_property_set_->insert(
+        std::pair<const CdmSessionId,
+                  const CdmClientPropertySet*>(session_id, property_set));
+  return result.second;
+}
+
+bool Properties::RemoveSessionPropertySet(const CdmSessionId& session_id) {
+  if (NULL == session_property_set_.get()) {
+    return false;
+  }
+  return (1 == session_property_set_->erase(session_id));
+}
+
+const CdmClientPropertySet* Properties::GetCdmClientPropertySet(
+  const CdmSessionId& session_id) {
+  if (NULL != session_property_set_.get()) {
+    CdmClientPropertySetMap::const_iterator it =
+        session_property_set_->find(session_id);
+    if (it != session_property_set_->end()) {
+      return it->second;
+    }
+  }
+  return NULL;
+}
+
+const std::string Properties::GetSecurityLevel(const CdmSessionId& session_id) {
+  const CdmClientPropertySet* property_set =
+      GetCdmClientPropertySet(session_id);
+  if (NULL == property_set) {
+    LOGE("Properties::GetSecurityLevel: cannot find property set for %s",
+         session_id.c_str());
+    return "";
+  }
+  return property_set->security_level();
+}
+
+const std::vector<uint8_t> Properties::GetServiceCertificate(
+    const CdmSessionId& session_id) {
+  const CdmClientPropertySet* property_set =
+      GetCdmClientPropertySet(session_id);
+  if (NULL == property_set) {
+    LOGE("Properties::GetServiceCertificate: cannot find property set for %s",
+         session_id.c_str());
+    return std::vector<uint8_t>();
+  }
+  return property_set->service_certificate();
+}
+
+bool Properties::UsePrivacyMode(const CdmSessionId& session_id) {
+  const CdmClientPropertySet* property_set =
+      GetCdmClientPropertySet(session_id);
+  if (NULL == property_set) {
+    LOGE("Properties::UsePrivacyMode: cannot find property set for %s",
+         session_id.c_str());
+    return false;
+  }
+  return property_set->use_privacy_mode();
+}
 }  // namespace wvcdm