HLS support for SESSION_KEYS

added Component::Input: network streams label

The manifest contains EXT-X-SESSION-KEY containing link to a drm/session key.\ In the past I've already encountered streams with protection policies (DRM, TTL tokens and so on) that were not handled by VLC.\ Is that an expected behaviour or a bug ?\

As the following lines return nothing, it must be not implemented.

/vlc-3.0.6$ sudo grep -R "EXT-X-SESSION-KEY" .
/vlc-3.0.6$ sudo grep -R "EXT-X-SESSION-DATA" .

These new keys are part of RFC 8216.

Here is the concerned manifest:

#EXTM3U
#EXT-X-VERSION:4
## Created with Unified Streaming Platform(version=1.8.5)
#EXT-X-SESSION-KEY:METHOD=AES-128,URI="https://aes-license.drm.technology/aes/getkey/vrt/8edf3bdf-7db3-41c3-a318-72cb7f82de66"

# AUDIO groups
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="audio-aacl-64",NAME="Dutch/Flemish",LANGUAGE="nl",AUTOSELECT=YES,DEFAULT=YES,CHANNELS="2"
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="audio-aacl-128",NAME="Dutch/Flemish",LANGUAGE="nl",AUTOSELECT=YES,DEFAULT=YES,CHANNELS="2"

# SUBTITLES groups
#EXT-X-MEDIA:TYPE=SUBTITLES,GROUP-ID="textstream",NAME="Dutch/Flemish",LANGUAGE="nl",AUTOSELECT=YES,DEFAULT=YES,URI="live_aes-text_track_0_dut=1000.m3u8"

# variants
#EXT-X-STREAM-INF:BANDWIDTH=245000,AVERAGE-BANDWIDTH=223000,CODECS="mp4a.40.2,avc1.42C01E",RESOLUTION=416x234,FRAME-RATE=25,AUDIO="audio-aacl-64",SUBTITLES="textstream",CLOSED-CAPTIONS=NONE
live_aes-audio_track_0_dut=64000-video=145000.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=576000,AVERAGE-BANDWIDTH=524000,CODECS="mp4a.40.2,avc1.42C01E",RESOLUTION=480x270,FRAME-RATE=25,AUDIO="audio-aacl-128",SUBTITLES="textstream",CLOSED-CAPTIONS=NONE
live_aes-audio_track_0_dut=128000-video=365000.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=1002000,AVERAGE-BANDWIDTH=911000,CODECS="mp4a.40.2,avc1.42C01E",RESOLUTION=640x360,FRAME-RATE=25,AUDIO="audio-aacl-128",SUBTITLES="textstream",CLOSED-CAPTIONS=NONE
live_aes-audio_track_0_dut=128000-video=730000.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=1433000,AVERAGE-BANDWIDTH=1303000,CODECS="mp4a.40.2,avc1.42C01F",RESOLUTION=768x432,FRAME-RATE=25,AUDIO="audio-aacl-128",SUBTITLES="textstream",CLOSED-CAPTIONS=NONE
live_aes-audio_track_0_dut=128000-video=1100000.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=2483000,AVERAGE-BANDWIDTH=2257000,CODECS="mp4a.40.2,avc1.4D401F",RESOLUTION=960x540,FRAME-RATE=25,AUDIO="audio-aacl-128",SUBTITLES="textstream",CLOSED-CAPTIONS=NONE
live_aes-audio_track_0_dut=128000-video=2000000.m3u8

# keyframes
#EXT-X-I-FRAME-STREAM-INF:BANDWIDTH=22000,CODECS="avc1.42C01E",RESOLUTION=416x234,URI="keyframes/live_aes-video=145000.m3u8"
#EXT-X-I-FRAME-STREAM-INF:BANDWIDTH=54000,CODECS="avc1.42C01E",RESOLUTION=480x270,URI="keyframes/live_aes-video=365000.m3u8"
#EXT-X-I-FRAME-STREAM-INF:BANDWIDTH=107000,CODECS="avc1.42C01E",RESOLUTION=640x360,URI="keyframes/live_aes-video=730000.m3u8"
#EXT-X-I-FRAME-STREAM-INF:BANDWIDTH=161000,CODECS="avc1.42C01F",RESOLUTION=768x432,URI="keyframes/live_aes-video=1100000.m3u8"
#EXT-X-I-FRAME-STREAM-INF:BANDWIDTH=292000,CODECS="avc1.4D401F",RESOLUTION=960x540,URI="keyframes/live_aes-video=2000000.m3u8"

If it is an expected behavior (which I doubt) there should be a clear warning message that would popup.

Sadly in meantime I replaced VLC by PotPlayer on my computers since I use many streams with DRM header daily.

After further investigations it seems that many part of RFC 8216 are not implemented in the VLC/modules/demux/hls.

The following keys are not in VLC/modules/demux/hls/playlist/tags.cpp (const exttagmapping)

                  4.3.1.2. EXT-X-VERSION .............................12
                  4.3.2.2. EXT-X-BYTERANGE ...........................14
                  4.3.2.7. EXT-X-DATERANGE ...........................18
                  4.3.4.3. EXT-X-I-FRAME-STREAM-INF ..................33
                  4.3.4.4. EXT-X-SESSION-DATA ........................34
                  4.3.4.5. EXT-X-SESSION-KEY .........................35
                  4.3.5.1. EXT-X-INDEPENDENT-SEGMENTS ................35
                  4.3.5.2. EXT-X-START ...............................36

Note : EXT-X-VERSION is not in mapping table but tested in switch case bellow it, must have been forgotten.

In our exemple it means that the following playlist line is never properly parsed:

#EXT-X-SESSION-KEY:METHOD=AES-128,URI="https://aes-license.drm.technology/aes/getkey/vrt/8edf3bdf-7db3-41c3-a318-72cb7f82de66"

As #EXT-X-SESSION-KEY is not implemented, no call to given URI is done to get AES_128 decoding key.

If i'm right, the same mechanism of decoding as in #EXT-X-KEY case must be done. (ex: VLC/modules/demux/hls/playlist/Parser.cpp)

I'm up to try implementing it, even if cpp isn't my main language. I'll try to provide a patch in the following weeks.

@François Cartegnie let me know if it's not already done but not merged on your side.

changed title from A valid stream don't play in VLC to HLS support for SESSION_KEYS

added Component::Demuxers label and removed Component::Input: network streams label

added Severity::normal label

changed milestone to %Features paradize

Replying to [comment:4 Grégoire Cutzach]:

After further investigations it seems that many part of RFC 8216 are not implemented in the VLC/modules/demux/hls.

You're wrong. SESSION_KEY is another example of how broken HLS is. Its only purpose is to PRELOAD a unique KEY...

If the stream doesn't work, that's another issue, since the KEY is still mandatory, because content can be encrypted... or not, and AES-128 CBC can't tell.

540c383f

added Status::fixed label

closed

added Component::Demux: Adaptive label and removed Component::Demuxers label

HLS support for SESSION_KEYS

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