Merge changes I5271f961,I8a75d2e1 into sc-widevine-release

* changes:
  Added debugOtaKeyboxFallbackDuration property.
  Update fallback policy for fast fallback.

libwvdrmengine/cdm/core/src/cdm_engine.cpp

@@ -21,6 +21,7 @@
 #include "device_files.h"
 #include "file_store.h"
 #include "log.h"
+#include "okp_fallback_policy.h"
 #include "ota_keybox_provisioner.h"
 #include "properties.h"
 #include "string_conversions.h"
@@ -2154,4 +2155,26 @@ void CdmEngine::OkpCleanUp() {
   }
   okp_provisioner_.reset();
 }
+
+void CdmEngine::SetDefaultOtaKeyboxFallbackDurationRules() {
+  OkpCheck();
+  std::unique_lock<std::mutex> lock(okp_mutex_);
+  auto* system_fallback_policy = CryptoSession::GetOkpFallbackPolicy();
+  if (!system_fallback_policy) {
+    LOGW("No system fallback policy available");
+    return;
+  }
+  system_fallback_policy->SetDefaultBackoffDurationRules();
+}
+
+void CdmEngine::SetFastOtaKeyboxFallbackDurationRules() {
+  OkpCheck();
+  std::unique_lock<std::mutex> lock(okp_mutex_);
+  auto* system_fallback_policy = CryptoSession::GetOkpFallbackPolicy();
+  if (!system_fallback_policy) {
+    LOGW("No system fallback policy available");
+    return;
+  }
+  system_fallback_policy->SetFastBackoffDurationRules();
+}
 }  // namespace wvcdm

libwvdrmengine/cdm/core/src/okp_fallback_policy.cpp

@@ -16,11 +16,6 @@ namespace okp {
 using UniqueLock = std::unique_lock<std::mutex>;
 namespace {
 constexpr int64_t kErrorTime = -1;
-
-int64_t GenerateInitialBackoffDuration() {
-  return static_cast<int64_t>(CdmRandom::RandomInRange(
-      kMinInitialBackoffDuration, kMaxInitialBackoffDuration));
-}
 }  // namespace
 
 // static
@@ -131,11 +126,11 @@ void SystemFallbackPolicy::TriggerFallback() {
     info_.SetFirstCheckedTime(current_time);
   }
   info_.SetBackoffStartTime(GetCurrentTime());
-  if (info_.HasBackoffDuration()) {
-    // Doubling backoff duration for exponential backoff.
+  if (!fast_fallback_ && info_.HasBackoffDuration()) {
+    // Doubling backoff duration for exponential backoff.  Except when
+    // performing fast fallback off.
     info_.DoubleBackoffDuration();
   } else {
-    // Use a random backoff period to avoid server spam across all devices.
     info_.SetBackoffDuration(GenerateInitialBackoffDuration());
   }
   StoreInfo();
@@ -185,6 +180,37 @@ bool SystemFallbackPolicy::IsInFallbackMode() {
   return false;  // Only stored if previously in fallback and has ended.
 }
 
+void SystemFallbackPolicy::SetDefaultBackoffDurationRules() {
+  UniqueLock lock(mutex_);
+  fast_fallback_ = false;
+  if (state() == SystemState::kFallbackMode) {
+    LOGI("Ending fallback");
+    EndBackoffPeriod();
+  }
+  info_.ClearBackoffDuration();
+  StoreInfo();
+}
+
+void SystemFallbackPolicy::SetFastBackoffDurationRules() {
+  UniqueLock lock(mutex_);
+  fast_fallback_ = true;
+  if (state() == SystemState::kFallbackMode) {
+    LOGI("Ending fallback");
+    EndBackoffPeriod();
+  }
+  info_.ClearBackoffDuration();
+  StoreInfo();
+}
+
+int64_t SystemFallbackPolicy::GenerateInitialBackoffDuration() {
+  if (fast_fallback_) {
+    return kFastBackoffDuration;
+  }
+  // Use a random backoff period to avoid server spam across all devices.
+  return static_cast<int64_t>(CdmRandom::RandomInRange(
+      kMinInitialBackoffDuration, kMaxInitialBackoffDuration));
+}
+
 int64_t SystemFallbackPolicy::GetSecondsSinceBackoffStart() const {
   if (!info_.HasBackoffStartTime()) return 0;
   const int64_t backoff_start_time = info_.backoff_start_time();