Issues with appletv+ streams (HLS/SAMPLE-AES (CBC)/WIDEVINE)

[glennguy]

Hi @peak3d

There is finally a request for help with SAMPLE-AES that isn't fairplay only!

@matthuisman and I have been trying over the last couple of days to debug why these won't work, and we've hit a bit of a dead end but have a lot to share in order to help you find a solution and thought it might be best to gather all related information in one issue.

I'll get Matt to email you a sample addon/strm file and how to get up and running with it.

We're working off the hlskid branch btw, allowing SAMPLE-AES as a valid method in HLSTree.cpp

The issues so far:

1. Our research indicates that SAMPLE-AES is likely indicating CBC rather than CTR AES method. The playready header includes this: <KID ALGID="AESCBC" VALUE="AAAAAOYDRndjMiAgICAgIA=="></KID> Changing the 3 instances of kCenc to KCbcs in wvdecrypter didn't yield a positive result, although it does break decryption for cenc streams.

2. Licensing mechanism. Repeated calls to the license server will end up returning a json payload with no license. We've found that when stopping the stream in the web browser, a challenge is made to the server but the json payload sent has "license-action": "STOP" instead of "START". Presumably this is to limit concurrent streams. Waiting 5 minutes or so seems to alleviate this but is there scope to contact the license server when stopping playback?

3. There are crashes happening when playing video+audio. Unlike with Disney+ the audio streams are also encrypted. I've done my best to debug (which is extremely painful due to anti-debug in widevinecdm 😄 ) and found the crash is happening because of https://github.com/peak3d/inputstream.adaptive/blob/hlskid/src/main.cpp#L2359. RemovePSSHSet is removing the representation that is pointed to by adaptiveTree_->current_representation_ - perhaps we need to do a select_stream after this? Setting media in the settings to video only works around the crash in our test stream. The root cause of this issue however may come back to setting the pssh type to NOTYPE in HLSTree.cpp. fixed in [HLS] set pssh media type for widevine #424

As always thanks for your time and effort in maintaining this ever growing project!

Log with manual streams media=all:
kodi.txt

Screenshot:

[matthuisman]

@peak3d
My pull request here:
#434
will allow SAMPLE-AES to pass if it's got the Widevine KEYFORMAT
(Well actually it lets everything pass as the behavior changed to only look for compatible)

[matthuisman]

@peak3d
Let me know when your ready for a test strm :)

[yoshimo]

after #461 can we mark the first part of the issue as solved?