android/libwvdrmengine/cdm/core/src/client_identification.cpp

// Copyright 2018 Google LLC. All Rights Reserved. This file and proprietary
// source code may only be used and distributed under the Widevine License
// Agreement.

#include "client_identification.h"

#include <string>

#include "crypto_session.h"
#include "license_protocol.pb.h"
#include "log.h"
#include "properties.h"
#include "string_conversions.h"
#include "wv_cdm_constants.h"

namespace wvcdm {
namespace {
const std::string kKeyCompanyName = "company_name";
const std::string kKeyModelName = "model_name";
const std::string kKeyModelYear = "model_year";
const std::string kKeyArchitectureName = "architecture_name";
const std::string kKeyDeviceName = "device_name";
const std::string kKeyProductName = "product_name";
const std::string kKeyBuildInfo = "build_info";
const std::string kKeyWvCdmVersion = "widevine_cdm_version";
const std::string kKeyOemCryptoSecurityPatchLevel =
    "oem_crypto_security_patch_level";
const std::string kKeyOemCryptoBuildInformation =
    "oem_crypto_build_information";

// These client identification keys are used by the CDM for relaying
// important device information that cannot be overwritten by the app.
const std::array<std::string, 10> kReservedProperties = {
    kKeyCompanyName,
    kKeyModelName,
    kKeyModelYear,
    kKeyArchitectureName,
    kKeyDeviceName,
    kKeyProductName,
    kKeyBuildInfo,
    kKeyWvCdmVersion,
    kKeyOemCryptoSecurityPatchLevel,
    kKeyOemCryptoBuildInformation,
    // TODO(b/148813171,b/142280599): include "origin" and "application_name"
    // to this list once collection of this information has been moved
    // to the core CDM.
};

// Checks if the client-provided |prop_name| is reserved for CDM device
// identification with the license server.  Property keys which are
// reserved should be dropped from the request.
bool IsPropertyKeyReserved(const std::string& prop_name) {
  for (const std::string& reserved_prop_name : kReservedProperties) {
    if (prop_name == reserved_prop_name) return true;
  }
  return false;
}
}  // namespace

// Protobuf generated classes.
using ClientCapabilities =
    video_widevine::ClientIdentification::ClientCapabilities;
using AnalogOutputCapabilities = ClientCapabilities::AnalogOutputCapabilities;
using video_widevine::ClientIdentification_NameValue;
using video_widevine::EncryptedClientIdentification;
using video_widevine::ProvisioningOptions;
using video_widevine::ProvisioningRequest;
using video_widevine::ProvisioningResponse;
using video_widevine::SignedProvisioningMessage;

CdmResponseType ClientIdentification::InitForProvisioningRequest(
    const std::string& client_token, CryptoSession* crypto_session) {
  if (crypto_session == nullptr) {
    LOGE("Crypto session not provided");
    return CdmResponseType(PARAMETER_NULL);
  }
  is_license_request_ = false;
  client_token_ = client_token;
  crypto_session_ = crypto_session;
  return CdmResponseType(NO_ERROR);
}

CdmResponseType ClientIdentification::InitForLicenseRequest(
    const std::string& client_token, CryptoSession* crypto_session) {
  if (crypto_session == nullptr) {
    LOGE("Crypto session not provided");
    return CdmResponseType(PARAMETER_NULL);
  }
  if (client_token.empty()) {
    LOGE("Client token is empty");
    return CdmResponseType(PARAMETER_NULL);
  }
  is_license_request_ = true;
  client_token_ = client_token;
  crypto_session_ = crypto_session;
  return CdmResponseType(NO_ERROR);
}

CdmResponseType ClientIdentification::InitForOtaKeyboxProvisioning(
    CryptoSession* crypto_session) {
  if (crypto_session == nullptr) {
    LOGE("Crypto session not provided");
    return CdmResponseType(PARAMETER_NULL);
  }
  is_okp_request_ = true;
  crypto_session_ = crypto_session;
  return CdmResponseType(NO_ERROR);
}

/*
 * Return the ClientIdentification message token type for provisioning request.
 * NOTE: a DRM Cert should never be presented to the provisioning server.
 */
CdmResponseType ClientIdentification::Prepare(
    const CdmAppParameterMap& app_parameters,
    const std::string& provider_client_token,
    video_widevine::ClientIdentification* client_id) {
  if (is_license_request_) {
    client_id->set_type(
        video_widevine::ClientIdentification::DRM_DEVICE_CERTIFICATE);
    client_id->set_token(client_token_);
  } else if (!client_token_.empty()) {
    // A token has been provided via InitForProvisioningRequest. This can only
    // happen in provisioning 4 (second stage) where an OEM cert is provided.
    client_id->set_type(
        video_widevine::ClientIdentification::OEM_DEVICE_CERTIFICATE);
    client_id->set_token(client_token_);
  } else if (!is_okp_request_) {
    // An OTA Keybox Provisioning request does not have a client id.
    // Otherwise this is a regular provisioning request.
    video_widevine::ClientIdentification::TokenType token_type;
    if (!GetProvisioningTokenType(&token_type)) {
      LOGE("Failed to get provisioning token type");
      return CdmResponseType(CLIENT_IDENTIFICATION_TOKEN_ERROR_1);
    }
    client_id->set_type(token_type);

    std::string token;
    std::string additional_token;
    CdmResponseType status =
        crypto_session_->GetProvisioningToken(&token, &additional_token);
    if (status != NO_ERROR) {
      LOGE("Failed to get provisioning token: status = %d", status.ToInt());
      return status;
    }
    client_id->set_token(token);
    if (!additional_token.empty()) {
      client_id->mutable_device_credentials()->set_token(additional_token);
    }
  }

  ClientIdentification_NameValue* client_info;
  if (is_license_request_) {
    CdmAppParameterMap::const_iterator iter;
    for (iter = app_parameters.begin(); iter != app_parameters.end(); ++iter) {
      if (IsPropertyKeyReserved(iter->first)) {
        LOGD("Discarding client property: name = \"%s\", value = \"%s\"",
             iter->first.c_str(), iter->second.c_str());
        continue;
      }
      client_info = client_id->add_client_info();
      client_info->set_name(iter->first);
      client_info->set_value(iter->second);
    }
  }
  std::string value;
  if (Properties::GetCompanyName(&value)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyCompanyName);
    client_info->set_value(value);
  }
  if (Properties::GetModelName(&value)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyModelName);
    client_info->set_value(value);
  }
  if (Properties::GetModelYear(&value)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyModelYear);
    client_info->set_value(value);
  }
  if (Properties::GetArchitectureName(&value)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyArchitectureName);
    client_info->set_value(value);
  }
  if (Properties::GetDeviceName(&value)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyDeviceName);
    client_info->set_value(value);
  }
  if (Properties::GetProductName(&value)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyProductName);
    client_info->set_value(value);
  }
  if (Properties::GetBuildInfo(&value)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyBuildInfo);
    client_info->set_value(value);
  }
  if (Properties::GetWVCdmVersion(&value)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyWvCdmVersion);
    client_info->set_value(value);
  }
  client_info = client_id->add_client_info();
  client_info->set_name(kKeyOemCryptoSecurityPatchLevel);
  client_info->set_value(
      std::to_string((uint32_t)crypto_session_->GetSecurityPatchLevel()));
  std::string oec_build_info;
  if (crypto_session_->GetBuildInformation(&oec_build_info)) {
    client_info = client_id->add_client_info();
    client_info->set_name(kKeyOemCryptoBuildInformation);
    client_info->set_value(oec_build_info);
  }
  if (!provider_client_token.empty()) {
    client_id->set_provider_client_token(provider_client_token);
  }

  if (is_okp_request_) {
    // Capabilities is not important for OTA keybox provisionining.
    return CdmResponseType(NO_ERROR);
  }

  ClientCapabilities* client_capabilities =
      client_id->mutable_client_capabilities();

  client_capabilities->set_client_token(true);

  if (is_license_request_) {
    bool supports_usage_table;
    if (crypto_session_->HasUsageTableSupport(&supports_usage_table)) {
      client_capabilities->set_session_token(supports_usage_table);
    }

    client_capabilities->set_anti_rollback_usage_table(
        crypto_session_->IsAntiRollbackHwPresent());
  }

  uint32_t api_version = 0;
  if (crypto_session_->GetApiVersion(&api_version)) {
    client_capabilities->set_oem_crypto_api_version(api_version);
  }

  if (is_license_request_) {
    CryptoSession::HdcpCapability current_version, max_version;
    if (crypto_session_->GetHdcpCapabilities(&current_version, &max_version) ==
        NO_ERROR) {
      switch (max_version) {
        case HDCP_NONE:
          client_capabilities->set_max_hdcp_version(
              ClientCapabilities::HDCP_NONE);
          break;
        case HDCP_V1:
          client_capabilities->set_max_hdcp_version(
              ClientCapabilities::HDCP_V1);
          break;
        case HDCP_V2:
          client_capabilities->set_max_hdcp_version(
              ClientCapabilities::HDCP_V2);
          break;
        case HDCP_V2_1:
          client_capabilities->set_max_hdcp_version(
              ClientCapabilities::HDCP_V2_1);
          break;
        case HDCP_V2_2:
          client_capabilities->set_max_hdcp_version(
              ClientCapabilities::HDCP_V2_2);
          break;
        case HDCP_V2_3:
          client_capabilities->set_max_hdcp_version(
              ClientCapabilities::HDCP_V2_3);
          break;
        case HDCP_NO_DIGITAL_OUTPUT:
          client_capabilities->set_max_hdcp_version(
              ClientCapabilities::HDCP_NO_DIGITAL_OUTPUT);
          break;
        default:
          LOGW("Unexpected HDCP max capability version: max_version = %d",
               static_cast<int>(max_version));
      }
    }
  }

  CryptoSession::SupportedCertificateTypes supported_certs;
  if (crypto_session_->GetSupportedCertificateTypes(&supported_certs)) {
    if (supported_certs.rsa_2048_bit) {
      client_capabilities->add_supported_certificate_key_type(
          ClientCapabilities::RSA_2048);
    }
    if (supported_certs.rsa_3072_bit) {
      client_capabilities->add_supported_certificate_key_type(
          ClientCapabilities::RSA_3072);
    }
    if (supported_certs.ecc_secp256r1) {
      client_capabilities->add_supported_certificate_key_type(
          ClientCapabilities::ECC_SECP256R1);
    }
    if (supported_certs.ecc_secp384r1) {
      client_capabilities->add_supported_certificate_key_type(
          ClientCapabilities::ECC_SECP384R1);
    }
    if (supported_certs.ecc_secp521r1) {
      client_capabilities->add_supported_certificate_key_type(
          ClientCapabilities::ECC_SECP521R1);
    }
  }

  if (is_license_request_) {
    client_capabilities->set_can_update_srm(false);
    uint16_t srm_version;
    if (crypto_session_->GetSrmVersion(&srm_version) == NO_ERROR)
      client_capabilities->set_srm_version(srm_version);
  }
  bool can_support_output;
  bool can_disable_output;
  bool can_support_cgms_a;
  if (crypto_session_->GetAnalogOutputCapabilities(
          &can_support_output, &can_disable_output, &can_support_cgms_a)) {
    AnalogOutputCapabilities capabilities =
        ClientCapabilities::ANALOG_OUTPUT_NONE;

    if (can_support_output) {
      if (can_support_cgms_a) {
        capabilities = ClientCapabilities::ANALOG_OUTPUT_SUPPORTS_CGMS_A;
      } else {
        capabilities = ClientCapabilities::ANALOG_OUTPUT_SUPPORTED;
      }
    }
    client_capabilities->set_analog_output_capabilities(capabilities);
    client_capabilities->set_can_disable_analog_output(can_disable_output);
  } else {
    client_capabilities->set_analog_output_capabilities(
        ClientCapabilities::ANALOG_OUTPUT_UNKNOWN);
  }

  if (api_version >= OEM_CRYPTO_API_VERSION_SUPPORTS_RESOURCE_RATING_TIER) {
    uint32_t tier;
    if (crypto_session_->GetResourceRatingTier(&tier)) {
      client_capabilities->set_resource_rating_tier(tier);
    }
  }

  if (is_license_request_) {
    CdmWatermarkingSupport support;
    if (!crypto_session_->GetWatermarkingSupport(&support)) {
      // Assume not supported.
      support = kWatermarkingNotSupported;
    }
    switch (support) {
      case kWatermarkingNotSupported:
        client_capabilities->set_watermarking_support(
            ClientCapabilities::WATERMARKING_NOT_SUPPORTED);
        break;
      case kWatermarkingConfigurable:
        client_capabilities->set_watermarking_support(
            ClientCapabilities::WATERMARKING_CONFIGURABLE);
        break;
      case kWatermarkingAlwaysOn:
        client_capabilities->set_watermarking_support(
            ClientCapabilities::WATERMARKING_ALWAYS_ON);
        break;
    }
  }

  return CdmResponseType(NO_ERROR);
}

bool ClientIdentification::GetProvisioningTokenType(
    video_widevine::ClientIdentification::TokenType* token_type) {
  CdmClientTokenType token = crypto_session_->GetPreProvisionTokenType();
  switch (token) {
    case kClientTokenKeybox:
      *token_type = video_widevine::ClientIdentification::KEYBOX;
      return true;
    case kClientTokenOemCert:
      *token_type =
          video_widevine::ClientIdentification::OEM_DEVICE_CERTIFICATE;
      return true;
    case kClientTokenBootCertChain:
      *token_type =
          video_widevine::ClientIdentification::BOOT_CERTIFICATE_CHAIN;
      return true;
    case kClientTokenDrmCert:
    default:
      // shouldn't happen
      LOGE("Unexpected provisioning type: %d", static_cast<int>(token));
      return false;
  }
}

}  // namespace wvcdm