PlayReady PSSH/PRO from Manifest instead of MPD

[Doolali]

Quick question, how do you force dash.js to use the pssh/pro from the manifest instead of the mp4.

I have fixed some data in the manifest but when received the PlayReady license request on the server it's using the old data that's encoded into the mp4.

[dsilhavy]

Do you see multiple license requests? One with the pssh from the segments and one with the pssh from the manifest?

Usually the pssh from the manifest should be preferred by dash.js. However, there is no settings flag to control this. Can you check if it works when you uncomment the encrypted event:

        return {
            handleEvent: function (event) {
                switch (event.type) {
                    case 'encrypted':
                       
                       // if (event.initData) {
                         //   let initData = ArrayBuffer.isView(event.initData) ? event.initData.buffer : event.initData;
                          //  eventBus.trigger(events.NEED_KEY, {key: new NeedKey(initData, event.initDataType)});
                       // }
                        break;
                }
            }
        };

[dsilhavy]

@Doolali Any updates on this?

[Doolali]

As far as I remember we were only getting a single license request with the pssh from the segment.

@dsilhavy Will have a test this weekend and get back to you!

[dsilhavy]

@Doolali Is this issue still relevant or can we close it?

[dsilhavy]

Closing due to inactivity

[bbert]

I reopen this issue since I have somehow same question: how can we ignore the pssh from init segments (mp4) in case the pssh is provided in the manifest and differs from the one in init segment and while we should rely primarily on the pssh from manifest?

Also you can find in section 8 of DASH-IF guidelines regarding content protection: https://dashif-documents.azurewebsites.net/Guidelines-Security/master/Guidelines-Security.html#:~:text=Initialization%20segments%20SHOULD,specific%20ContentProtection%20descriptors.:
"Initialization segments SHOULD NOT contain any moov/pssh box ([CMAF], section 7.4.3) and DASH clients MAY ignore such boxes when encountered. Instead, pssh boxes required for DRM system initialization are part of the DRM system configuration and SHOULD be placed in the MPD as cenc:pssh elements in DRM system specific ContentProtection descriptors."

In dash.js, if we have pssh in manifest, shouldn't we ignore pssh from init segments?
@sandersaares any opinion?

[dsilhavy]

Easiest workaround would certainly be to add a settings flag like ignorePsshFromSegments or something similar.

I think ignoring it in general is dangerous. I saw streams that did not update the pssh in the manifest after a key rotation but only the one in the segments.

[bbert]

Yes, we should keep backward compatibility with those streams.
Settings flag is a good option.

[dsilhavy]

@bbert @Doolali As part of #3793 I added a new flag ignoreEmeEncryptedEvent . The flag disables the needkey handling in the ProtectionController:

    function _onNeedKey(event, retry) {
        if (!settings.get().streaming.protection.ignoreEmeEncryptedEvent) {
          // Rest of the code
      }
}

Is this sufficient for your use case?

[bbert]

Yes fine !! That's the way I tried

[dsilhavy]

Implemented as part of #3793 . In order to use this feature, adjust the settings as described here: https://github.com/Dash-Industry-Forum/dash.js/wiki/Digital-Rights-Management-(DRM)-and-license-acquisition#ignoring-init-data-from-the-pssh