commit 10fe943418d6aa574a9b48cfc9bf8aee70a6253d
author Robert Shih <robertshih@google.com> Sat Nov 09 08:26:49 2019 -0800
committer Robert Shih <robertshih@google.com> Tue Nov 12 11:55:50 2019 -0800
tree 7b032a7ff7a2e2dc414d6c0d86f95440a0f1bb36
parent e6cbccaef91a63e0a739f084fdc94a216a08efd6

DrmUtils: helpers to create hidl CryptoFactories/Plugins

Bug: 134787536
Test: testPocCVE_2017_13253
Change-Id: I3d71b249bd55d4895b5201d470f37817bcb5903b

drm/libmediadrm/DrmUtils.cpp

diff --git a/drm/libmediadrm/DrmUtils.cpp b/drm/libmediadrm/DrmUtils.cpp
index 5cfd7c0..c8956bf 100644
--- a/drm/libmediadrm/DrmUtils.cpp
+++ b/drm/libmediadrm/DrmUtils.cpp
@@ -17,6 +17,15 @@
 //#define LOG_NDEBUG 0
 #define LOG_TAG "DrmUtils"
 
+#include <android/hardware/drm/1.0/ICryptoFactory.h>
+#include <android/hardware/drm/1.0/ICryptoPlugin.h>
+#include <android/hardware/drm/1.1/ICryptoFactory.h>
+#include <android/hardware/drm/1.2/ICryptoFactory.h>
+#include <android/hidl/manager/1.0/IServiceManager.h>
+#include <hidl/HidlSupport.h>
+
+#include <utils/Errors.h>
+#include <utils/Log.h>
 #include <utils/String16.h>
 #include <binder/IInterface.h>
 #include <binder/IServiceManager.h>
@@ -29,6 +38,12 @@
 #include <mediadrm/IDrm.h>
 #include <mediadrm/IMediaDrmService.h>
 
+using HServiceManager = ::android::hidl::manager::V1_0::IServiceManager;
+using ::android::hardware::hidl_array;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using namespace ::android::hardware::drm;
+
 namespace android {
 namespace DrmUtils {
 
@@ -67,6 +82,57 @@
         return new Hal();
     }
 }
+
+template <typename Hal, typename V>
+void MakeCryptoFactories(const uint8_t uuid[16], V &cryptoFactories) {
+    sp<HServiceManager> serviceManager = HServiceManager::getService();
+    if (serviceManager == nullptr) {
+        ALOGE("Failed to get service manager");
+        exit(-1);
+    }
+
+    serviceManager->listByInterface(Hal::descriptor, [&](const hidl_vec<hidl_string> &registered) {
+        for (const auto &instance : registered) {
+            auto factory = Hal::getService(instance);
+            if (factory != nullptr) {
+                ALOGI("found %s %s", Hal::descriptor, instance.c_str());
+                if (factory->isCryptoSchemeSupported(uuid)) {
+                    cryptoFactories.push_back(factory);
+                }
+            }
+        }
+    });
+}
+
+hidl_vec<uint8_t> toHidlVec(const void *ptr, size_t size) {
+    hidl_vec<uint8_t> vec(size);
+    if (ptr != nullptr) {
+        memcpy(vec.data(), ptr, size);
+    }
+    return vec;
+}
+
+hidl_array<uint8_t, 16> toHidlArray16(const uint8_t *ptr) {
+    if (ptr == nullptr) {
+        return hidl_array<uint8_t, 16>();
+    }
+    return hidl_array<uint8_t, 16>(ptr);
+}
+
+sp<::V1_0::ICryptoPlugin> MakeCryptoPlugin(const sp<::V1_0::ICryptoFactory> &factory,
+                                           const uint8_t uuid[16], const void *initData,
+                                           size_t initDataSize) {
+    sp<::V1_0::ICryptoPlugin> plugin;
+    factory->createPlugin(toHidlArray16(uuid), toHidlVec(initData, initDataSize),
+                          [&](::V1_0::Status status, const sp<::V1_0::ICryptoPlugin> &hPlugin) {
+                              if (status != ::V1_0::Status::OK) {
+                                  return;
+                              }
+                              plugin = hPlugin;
+                          });
+    return plugin;
+}
+
 } // namespace
 
 bool UseDrmService() {
@@ -81,5 +147,22 @@
     return MakeObject<ICrypto, CryptoHal>(pstatus);
 }
 
+std::vector<sp<::V1_0::ICryptoFactory>> MakeCryptoFactories(const uint8_t uuid[16]) {
+    std::vector<sp<::V1_0::ICryptoFactory>> cryptoFactories;
+    MakeCryptoFactories<::V1_0::ICryptoFactory>(uuid, cryptoFactories);
+    MakeCryptoFactories<::V1_1::ICryptoFactory>(uuid, cryptoFactories);
+    MakeCryptoFactories<::V1_2::ICryptoFactory>(uuid, cryptoFactories);
+    return cryptoFactories;
+}
+
+std::vector<sp<ICryptoPlugin>> MakeCryptoPlugins(const uint8_t uuid[16], const void *initData,
+                                                 size_t initDataSize) {
+    std::vector<sp<ICryptoPlugin>> plugins;
+    for (const auto &factory : MakeCryptoFactories(uuid)) {
+        plugins.push_back(MakeCryptoPlugin(factory, uuid, initData, initDataSize));
+    }
+    return plugins;
+}
+
 }  // namespace DrmUtils
 }  // namespace android