android/libwvdrmengine/aidl_src/WVDrmFactory.cpp

//
// Copyright 2021 Google LLC. All Rights Reserved. This file and proprietary
// source code may only be used and distributed under the Widevine License
// Agreement.
//

//#define LOG_NDEBUG 0
#define LOG_TAG "WVCdm-DrmFactory"

#include "WVDrmFactory.h"

#include <android/binder_ibinder_platform.h>
#include <binder/IPCThreadState.h>
#include <utils/Log.h>

#include "Utils.h"
#include "WVCDMSingleton.h"
#include "WVCryptoPlugin.h"
#include "WVDrmPlugin.h"
#include "WVUUID.h"
#include "android-base/properties.h"
#include "cutils/properties.h"
#include "wv_cdm_constants.h"
#include "wv_content_decryption_module.h"
#include "wv_metrics.h"

namespace wvdrm {
namespace hardware {
namespace drm {
namespace widevine {

using std::string;
using std::vector;

using ::aidl::android::hardware::drm::CryptoSchemes;
using ::aidl::android::hardware::drm::SecurityLevel;
using ::aidl::android::hardware::drm::Status;
using ::aidl::android::hardware::drm::SupportedContentType;
using ::aidl::android::hardware::drm::Uuid;

WVGenericCryptoInterface WVDrmFactory::sOemCryptoInterface;

bool WVDrmFactory::isCryptoSchemeSupported(const Uuid& in_uuid) {
  return isWidevineUUID(in_uuid.uuid.data());
}

::ndk::ScopedAStatus WVDrmFactory::createCryptoPlugin(
    const ::aidl::android::hardware::drm::Uuid& in_uuid,
    const std::vector<uint8_t>& in_initData,
    std::shared_ptr<::aidl::android::hardware::drm::ICryptoPlugin>*
        _aidl_return) {
  const auto& self = android::IPCThreadState::self();
  const char* sid = self->getCallingSid();
  sid = sid ? (std::strstr(sid, "mediadrmserver") ? sid : "app") : "nullptr";
  ALOGI("[%s] calling %s", sid, __PRETTY_FUNCTION__);

  if (!isCryptoSchemeSupported(in_uuid)) {
    ALOGE(
        "Widevine Drm HAL: failed to create crypto plugin, "
        "invalid crypto scheme");
    *_aidl_return = nullptr;
    return toNdkScopedAStatus(Status::ERROR_DRM_CANNOT_HANDLE);
  }

  std::shared_ptr<WVCryptoPlugin> plugin =
      ::ndk::SharedRefBase::make<WVCryptoPlugin>(in_initData.data(),
                                                 in_initData.size(), getCDM());
  AIBinder_setRequestingSid(plugin->asBinder().get(), true);
  *_aidl_return = std::move(plugin);
  return toNdkScopedAStatus(Status::OK);
}

::ndk::ScopedAStatus WVDrmFactory::createDrmPlugin(
    const Uuid& in_uuid, const string& in_appPackageName,
    std::shared_ptr<::aidl::android::hardware::drm::IDrmPlugin>* _aidl_return) {
  const auto& self = ::android::IPCThreadState::self();
  const char* sid = self->getCallingSid();
  sid = sid ? (std::strstr(sid, "mediadrmserver") ? sid : "app") : "nullptr";
  ALOGI("[%s][%s] calling %s", sid, in_appPackageName.c_str(),
        __PRETTY_FUNCTION__);

  if (!isCryptoSchemeSupported(in_uuid)) {
    ALOGE(
        "Widevine Drm HAL: failed to create drm plugin, "
        "invalid crypto scheme");
    *_aidl_return = nullptr;
    return toNdkScopedAStatus(Status::ERROR_DRM_CANNOT_HANDLE);
  }

  if (!isBlankAppPackageNameAllowed() && in_appPackageName.empty()) {
    ALOGE(
        "Widevine Drm HAL: Failed to create DRM Plugin, blank App Package "
        "Name disallowed.");
    *_aidl_return = nullptr;
    return toNdkScopedAStatus(Status::ERROR_DRM_CANNOT_HANDLE);
  }

  std::shared_ptr<WVDrmPlugin> plugin = ::ndk::SharedRefBase::make<WVDrmPlugin>(
      getCDM(), in_appPackageName.c_str(), &sOemCryptoInterface,
      areSpoidsEnabled());

  AIBinder_setRequestingSid(plugin->asBinder().get(), true);
  *_aidl_return = plugin;
  return toNdkScopedAStatus(Status::OK);
}

bool WVDrmFactory::areSpoidsEnabled() {
  return firstApiLevel() >= 26;  // Android O
}

bool WVDrmFactory::isBlankAppPackageNameAllowed() {
  return firstApiLevel() < 29;  // Android Q
}

int32_t WVDrmFactory::firstApiLevel() {
  // Check what this device's first API level was.
  int32_t firstApiLevel =
      android::base::GetIntProperty<int32_t>("ro.product.first_api_level", 0);
  if (firstApiLevel == 0) {
    // First API Level is 0 on factory ROMs, but we can assume the current SDK
    // version is the first if it's a factory ROM.
    firstApiLevel =
        android::base::GetIntProperty<int32_t>("ro.build.version.sdk", 0);
  }
  return firstApiLevel;
}

::ndk::ScopedAStatus WVDrmFactory::getSupportedCryptoSchemes(
    CryptoSchemes* _aidl_return) {
  CryptoSchemes schemes{};
  for (const auto& uuid : wvdrm::getSupportedCryptoSchemes()) {
    schemes.uuids.push_back({uuid});
  }

  bool isL1 = wvcdm::WvContentDecryptionModule::IsSecurityLevelSupported(wvcdm::kSecurityLevelL1);
  for (auto mime : {wvcdm::ISO_BMFF_VIDEO_MIME_TYPE, wvcdm::ISO_BMFF_AUDIO_MIME_TYPE,
                    wvcdm::WEBM_VIDEO_MIME_TYPE,     wvcdm::WEBM_AUDIO_MIME_TYPE,
                    wvcdm::CENC_INIT_DATA_FORMAT,    wvcdm::HLS_INIT_DATA_FORMAT,
                    wvcdm::WEBM_INIT_DATA_FORMAT}) {
      bool isAudio = wvcdm::WvContentDecryptionModule::IsAudio(mime);
      SupportedContentType ct{mime, SecurityLevel::SW_SECURE_CRYPTO, SecurityLevel::SW_SECURE_DECODE};
      if (isL1) {
          ct.maxLevel = isAudio ? SecurityLevel::HW_SECURE_DECODE : SecurityLevel::HW_SECURE_ALL;
      }
      schemes.mimeTypes.push_back(ct);
  }
  *_aidl_return = schemes;
  return ::ndk::ScopedAStatus::ok();
}

string WVDrmFactory::stringToHex(const string& input) {
  // If input contains punctuations that are not part of
  // a valid server url, we need to convert it to hex.
  const string validChars = "/-._~%:";
  bool toHex = false;
  for (const char ch : input) {
    if (ispunct(ch) != 0 && validChars.find(ch) == string::npos) {
      toHex = true;
      break;
    }
  }
  if (!toHex) return input;

  static constexpr char hex[] = "0123456789ABCDEF";

  string output;
  output.reserve(input.length() * 2);
  for (const unsigned char ch : input) {
    output.push_back(hex[ch >> 4]);
    output.push_back(hex[ch & 15]);
  }
  return output;
}

void WVDrmFactory::printCdmMetrics(int fd) {
  dprintf(fd, "\n**** Widevine Cdm Metrics ****\n");

  // Verify that the version of the library that we linked against is
  // compatible with the version of the headers we compiled against.
  GOOGLE_PROTOBUF_VERIFY_VERSION;

  android::sp<wvcdm::WvContentDecryptionModule> cdm(getCDM());

  vector<drm_metrics::WvCdmMetrics> metrics;
  bool full_list_returned = true;
  wvcdm::CdmResponseType result =
      cdm->GetMetrics(&metrics, &full_list_returned);
  if (metrics.empty()) {
    dprintf(fd,
            "Metrics not available, please retry while streaming a video\n");
  } else if (!full_list_returned) {
    dprintf(fd,
            "Not all metrics are returned due to some GetMetric error, "
            "please check logcat for possible GetMetric errors.\n");
  }
  if (result == wvcdm::NO_ERROR) {
    for (auto& metric : metrics) {
      dprintf(fd, "*** Metric size=%zu\n", metric.DebugString().size());
      string formatted;
      wv_metrics::FormatWvCdmMetrics(metric, formatted);
      dprintf(fd, "%s\n", formatted.c_str());
    }
  } else {
    dprintf(fd, "GetMetrics failed, error=%d\n", result);
  }
}

void WVDrmFactory::printCdmProperties(int fd) {
  dprintf(fd, "\n**** Widevine CDM properties ****\n");

  android::sp<wvcdm::WvContentDecryptionModule> cdm(getCDM());

  const bool isLevel1 =
      cdm->IsSecurityLevelSupported(wvcdm::CdmSecurityLevel::kSecurityLevelL1);
  dprintf(fd, "default security level: [%s]\n", isLevel1 ? "L1" : "L3");

  const std::map<string, string> cdmProperties = {
      {"version- Widevine CDM:", wvcdm::QUERY_KEY_WVCDM_VERSION},
      {"version- current SRM:", wvcdm::QUERY_KEY_CURRENT_SRM_VERSION},
      {"version(major)- OEM Crypto API:",
       wvcdm::QUERY_KEY_OEMCRYPTO_API_VERSION},
      {"version(minor)- OEM Crypto API:",
       wvcdm::QUERY_KEY_OEMCRYPTO_API_MINOR_VERSION},
      {"id- device:", wvcdm::QUERY_KEY_DEVICE_ID},
      {"id- system:", wvcdm::QUERY_KEY_SYSTEM_ID},
      {"renewal server url:", wvcdm::QUERY_KEY_RENEWAL_SERVER_URL},
      {"hdcp level- max:", wvcdm::QUERY_KEY_MAX_HDCP_LEVEL},
      {"hdcp level- current:", wvcdm::QUERY_KEY_CURRENT_HDCP_LEVEL},
      {"num sessions- max supported:", wvcdm::QUERY_KEY_MAX_NUMBER_OF_SESSIONS},
      {"num sessions- opened:", wvcdm::QUERY_KEY_NUMBER_OF_OPEN_SESSIONS},
      {"resource rating tier:", wvcdm::QUERY_KEY_RESOURCE_RATING_TIER},
      {"support decrypt hash:", wvcdm::QUERY_KEY_DECRYPT_HASH_SUPPORT},
      {"support SRM update:", wvcdm::QUERY_KEY_SRM_UPDATE_SUPPORT},
      {"support usage table:", wvcdm::QUERY_KEY_USAGE_SUPPORT},
      {"max usage table entries:", wvcdm::QUERY_KEY_MAX_USAGE_TABLE_ENTRIES},
      {"OEM Crypto build info:", wvcdm::QUERY_KEY_OEMCRYPTO_BUILD_INFORMATION},
      {"provisioning id:", wvcdm::QUERY_KEY_PROVISIONING_ID},
      {"provisioning model:", wvcdm::QUERY_KEY_PROVISIONING_MODEL},
      {"analog capabilities:", wvcdm::QUERY_KEY_ANALOG_OUTPUT_CAPABILITIES},
      {"can disable analog output:",
       wvcdm::QUERY_KEY_CAN_DISABLE_ANALOG_OUTPUT},
  };

  string value;
  for (const auto& property : cdmProperties) {
    cdm->QueryStatus(wvcdm::RequestedSecurityLevel::kLevelDefault,
                     property.second, &value);
    string outString = stringToHex(value);
    dprintf(fd, "%s [%s]\n", property.first.c_str(), outString.c_str());
    value.clear();
  }
}

void WVDrmFactory::printUsage(int fd) {
  dprintf(fd, "\nDefault to print all info if no arguments are used.\n");
  dprintf(fd, "Optional arguments are:\n");
  dprintf(fd, "\ta:print all info | m:cdm metrics | p:cdm properties\n");
  dprintf(fd,
          "Usage: adb shell dumpsys "
          "android.hardware.drm::IDrmFactory/widevine [-a|-h|-m|-p]\n");
}

binder_status_t WVDrmFactory::dump(int fd, const char** args,
                                   uint32_t numArgs) {
  if (fd < 0) {
    ALOGE("%s: missing fd for writing", __FUNCTION__);
    return STATUS_BAD_VALUE;
  }

  bool dumpCdmProperties, dumpCdmMetrics = false;
  if (numArgs == 0) {
    // default to print all info if no arguments are given
    dumpCdmProperties = dumpCdmMetrics = true;
  } else {
    for (auto&& str : std::vector<std::string_view>{args, args + numArgs}) {
      string option = str.data();
      if (option.find("-a") != string::npos ||
          option.find("-A") != string::npos) {
        dumpCdmProperties = dumpCdmMetrics = true;
      } else if (option.find("-m") != string::npos ||
                 option.find("-M") != string::npos) {
        dumpCdmMetrics = true;
      } else if (option.find("-p") != string::npos ||
                 option.find("-P") != string::npos) {
        dumpCdmProperties = true;
      } else if (option.find("-h") != string::npos ||
                 option.find("-H") != string::npos) {
        printUsage(fd);
      } else {
        dprintf(fd, "Invalid arg: %s\n", option.c_str());
        printUsage(fd);
      }
    }
  }

  if (dumpCdmMetrics) printCdmMetrics(fd);
  if (dumpCdmProperties) printCdmProperties(fd);
  fsync(fd);

  return STATUS_OK;
}

}  // namespace widevine
}  // namespace drm
}  // namespace hardware
}  // namespace wvdrm