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Matt Feddersen 28ec8548c6 Source release 18.5.0
2024-03-28 19:15:22 -07:00

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Widevine CE CDM 18.5.0

Released 2024-03-28

Getting Started

This project contains the sources for building a Widevine CDM module. Read the following to learn more about the contents of this project and how to use them:

The Widevine Developer Site documents the CDM API and describes how to integrate the CDM into a system.

New in v18.5.0

Note: Releases v18.2-18.4 were skipped so that this release's version number matches the OEMCrypto version.

It is strongly recommended for partners to update from v18.1 to v18.5 to address two major bugs in the CE CDM code which could result in lost offline licenses or app crashes. See Bug Fixes for details.

Features

  • Supports up to OEMCrypto v18.5, including new OEMCrypto tests introduced since OEMCrypto v18.1.
  • Added additional logging when license request fails, to help diagnose what went wrong.
  • Improved support for HDCP v1.0-1.4 version.
    • Cdm::getStatusForHdcpVersion() can now accept a specific HDCP 1.x minor version (specifically 1.0, 1.1, 1.2, 1.3, or 1.4) when checking if content can be decrypted.
    • The legacy behavior is still available via Cdm::HdcpVersion::kHdcp1_x.
    • See Bug Fixes note about related bug in previous versions.
  • Added support for Cast provisioning 4.0
    • Cast uses a slightly different provisioning 4.0 protocol compared to non-Cast cases. The additions to the protocol are internal to the library, and do not require API changes for CE CDM users
    • Additional tests are included, these tests will automatically skip for device which do not use provisioning 4.0.
  • Improved performance for unencrypted data provided via Cdm::decrypt().
    • Some apps are known to always use decrypt calls, even if parts of the data are completely unencrypted. The CDM will now check if samples/ sub-samples of decryption batch data can skip the decryption stage and instead directly copied to the secure output.
  • Various minor performance improvements
    • Reduced internal data copying.
    • Test runtime improvements:
      • Skipped set up for unsupported features.
      • Improved test data storage management.
      • Removed unused internal testing fixtures.
    • Compile time improvements by better dependency checks for third-party libraries.
  • CE CDM now compiles clean with -Wunused-parameter.
  • Added support for new provisioning flow for baked-in certificates on devices using Widevine's embedded device certificate.
    • Affected partners should check the L3 OEMCrypto documentation for details.
  • Added new tests for CE CDM and OEMCrypto v18.5 features.

Bug Fixes

  • Fixed major issue with loss of offline licenses when stored license count exceeds OEMCrypto's usage table size limit.
    • Issue only affects users with 300 or more downloaded offline licenses across all apps.
  • Fixed major issue with memory corruption when apps misuse the API by making certain key operations before license is loaded.
    • Specifically, if an app generates a license request via Cdm::generateRequest(), then calls Cdm::remove() before Cdm::update() with the license response it can cause the CDM to crash.
  • Fixed mistaken test failures when the CE CDM and OEMCrypto versions were not identical.
  • Fixed an issue with DRM certificate serial number stability for provisioning 4.0 devices.
    • This only affected very specific devices when going through their specific factory reset process.
    • Added additional tests to catch future, similar errors.
  • Fixed an issue with Cdm::getKeyStatuses() reporting error for certain licenses which use specific HDCP v1.x minor versions.
  • Fixed an issue with URL parsing in test code for renewal requests
    • Certain tests used special URL parameters which were not properly accounted for in the CE CDM's test utility code; this caused tests to fail on otherwise working devices.
  • Fixed the CAS tests sometimes not being skipped on non-CAS-supporting devices.
  • Removed tests that explicitly tested against Widevine's staging provisioning servers.
  • Fixed minor issue with tests which were generating many warnings from expected behavior.
    • These warning did not cause the tests to fail, but created a lot of noise when trying to diagnose other failures

CHANGELOG.md lists the major changes for each past release.

Contains No OEMCrypto

The CE CDM requires an implementation of OEMCrypto, our hardware abstraction layer, in order to compile and run successfully. If you are an OEMCrypto implementer, you should have access to the OEMCrypto partner repository, which contains additional source code and information about implementing OEMCrypto, including the Widevine-written OEMCrypto implementation, the OEMCrypto Porting Kit. (OPK) If you are not an OEMCrypto implementer, then you will need to get an OEMCrypto implementation from your SoC manufacturer before you can use the CE CDM.