Decryption: The Dungeon of Despair

[stabbedbybrick]

also regarding

4. If there's extra payload in the Payload tab of the license, that means you'll need to customize your script to handle the request in json format. This will require basic Python knowledge and some understanding of how the pywidevine module works in order to properly send a license request and parsing the response.

There is data in the response tab of the license beside response payload. Which script would I need to customize? l3.py?

A_n_g_e_l_a has written excellent examples of this in the first post in this very thread. There's even code snippets there that you can use as templates for other sites. Read through it carefully and test them out. Look over other scripts posted around the forum and compare them to each other. What are the similarities and differences between them? All these scripts work by sending a license request, so by pinpointing the difference in how it's formulated in each script will give you valuable knowledge. I know it's tempting to just run random code and look hungrily at the terminal, hoping that there will be juicy key there. But at best this will give you occasional and unintentional success, and at worst this could burn your CDM by making too many bad requests against the wrong server. Make intentional efforts to understand what you're doing, or this will be a very frustrating journey for you.

As for your other update, until you share more details about what service you're using, no one will be able to help you.

[Iridule]

@stabbedbybrick

I already have the files decrypted. The license server is correct. I've figured out the pattern to get keys for this site. It requires PSSH+LIC+token in headers.
Key decrypts full 1080p video fine with no error. Audio is decrypted in segments using yt-dlp. Video plays fine in entirety. Though no audio segments are downloaded with N_m3u8DL-RE downloader using the same MPD and the Audio file seems singular In size with much larger file size than yt-dlp, unable to decrypt I think? using that method. Or could be ffmpeg issue as I get aac bitstream errors of I try to join audio to video obtained using that method of download.

So to get around that I downloaded all 4 segments separately with yt-dlp decrypted them and renamed them and they match the video though for some reason vlc shows each separate file having a longer track length than it really does yet that longer length matches the video length.
There was no json needed. Now they only need to be joined together in one file. I suppose I could transfer them to phone and use a video editing tool and drop the audio files in.

[stabbedbybrick]

Since you are making it a point not to mention what site you're using, I'm just going to assume it's particularly embarrassing porn and move on.

I can't tell you what you're possibly doing wrong since I don't know where you're getting the files from, but if all you're looking to do is merging the segments, you can do that with ffmpeg:

ffmpeg -i audiofile1.m4a -i audiofile2.m4a -i audiofile3.m4a -i audiofile4.m4a -c copy audio.m4a
ffmpeg -i audio.m4a -i video.mp4 -c copy finalvideo.mp4

Theoretically, you should now have one final, working file.

[Iridule]

Since you are making it a point not to mention what site you're using, I'm just going to assume it's particularly embarrassing porn and move on.

I can't tell you what you're possibly doing wrong since I don't know where you're getting the files from, but if all you're looking to do is merging the segments, you can do that with ffmpeg:

ffmpeg -i audiofile1.m4a -i audiofile2.m4a -i audiofile3.m4a -i audiofile4.m4a -c copy audio.m4a
ffmpeg -i audio.m4a -i video.mp4 -c copy finalvideo.mp4

Theoretically, you should now have one final, working file.

In theory it should work. I tried last night it doesn't

$ffmpeg -i decrypted1.m4a -i decrypted2.m4a -i decrypted3.m4a -i decrypted4.m4a -c copy audio.m4a
[ipod @ 0x56041f198500] Could not find tag for codec eac3 in stream #0, codec not currently supported in container
Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
Error initializing output stream 0:0 --

The issue is with N_m38DL-RE i get one large audio file yet when trying to decrypt and merge It plays an ad then goes silent/garbled. If I run the same MPD through yt-dlp I get many parts with language markers which help but it is a pain to download all 4 english parts then decrypt each one one by one and then now merge them. Must be how the audio is segmented in the mpd to have advertisements. I tried passing the key through N_m3u8DL and merging like this

./N_m3u8DL-RE  -M format=mkv --key....

didn't work either...video decrypts fine but audio plays ad/or part of video in wrong time... then again goes silent. Maybe the MPD needs to be edited to remove ads?

[stabbedbybrick]

I know there are a few services out there that have ads baked in, but in most cases you can find an ad-free mpd or get the correct tracks through the manifests. But I can't give you blind advice, so I don't know. I guess you just have to experiment.

[Iridule]

I know there are a few services out there that have ads baked in, but in most cases you can find an ad-free mpd or get the correct tracks through the manifests. But I can't give you blind advice, so I don't know. I guess you just have to experiment.

Yt-dlp -F lists audio segments with no ads but it is a pain to get them all and in the right order for the video. Then decrypt each one individually. N_m3u8DL-RE does not show any way of which track is which and I have tried downloading/decrypting all it lists and the resulting file seems to play 1-5 second ad then garbled/silence...this must be a Server Side Advert Insertion ?
Yt-dl

[Attachment 70942 - Click to enlarge]
N_m3u8DL-RE

[Attachment 70943 - Click to enlarge]

[pram0dm]

I could give it a shot for you at my end using N_m3u8DL-RE if you can pass me the keys that you received from the license server, and the MPD URL.
Even the URL to the video would do just fine as long as it isn't behind a subscription.

[Iridule]

@pram0dm
I'll figure it out somehow...
I appreciate the offer, I think the issue is with the MPD. It needs to be edited to remove ad segments. At this point it may just be easier to transfer all to my phone and use playstore app to merge audio and video lol. Over I would say my progress to getting the key was a success which was my main goal. There is a way to properly do this im sure with N_m3u8DL I just haven't figured it out yet. But I will.

[Iridule]

@pram0dm
Got it...edited the MPD to remove ads Removed everything from <period>...roll-ad-blah-blah </period> until it started to say the second <period> line right before it talked about cenc...

<Period id="0" duration="PT11M56.716S">
    <AdaptationSet frameRate="24000/1001" id="0" contentType="video" par="16:9" maxWidth="1920" maxHeight="1080" segmentAlignment="true">
      <ContentProtection schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"

then loaded with N_m3u8DL.

./N_m3u8DL-RE -M format=mkv --key 4884blahblah8848:80943846 ~/Downloads/manifest.mpd --save-name MergeSuccess

All works even subtitles. Not bad for 5 days of starting this project
Now I will take a break and go outside before I get carpel tunnel.
P.S. In my searching I found this article useful https://tutorials.hybrik.com/drm/
Fiat Lux et Lux fit

[Attachment 70946 - Click to enlarge]

[Attachment 70947 - Click to enlarge]

[stabbedbybrick]

@pram0dm
Got it...edited the MPD to remove ads Removed everything from <period>...roll-ad-blah-blah </period> until it started to say the second <period> line right before it talked about cenc...

<Period id="0" duration="PT11M56.716S">
    <AdaptationSet frameRate="24000/1001" id="0" contentType="video" par="16:9" maxWidth="1920" maxHeight="1080" segmentAlignment="true">
      <ContentProtection schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"

then loaded with N_m3u8DL.

./N_m3u8DL-RE -M format=mkv --key 4884blahblah8848:80943846 ~/Downloads/manifest.mpd --save-name MergeSuccess

All works even subtitles. Not bad for 5 days of starting this project

Nice work! You seem determined and a fast learner, so you'll have all this figured out in no time

[Iridule]

@ stabbedbybrick

Nice work! You seem determined and a fast learner, so you'll have all this figured out in no time

Thanks, it was a fun project.

[paul92]

Is there anything specific guide to capturing, and decrypting live streams for own personal use? The majority of these guides seem to be for downloading from catch up and VOD videos.

[A_n_g_e_l_a]

Is there anything specific guide to capturing, and decrypting live streams for own personal use? The majority of these guides seem to be for downloading from catch up and VOD videos.

This is a guide for people starting out with decryption
Your more advanced needs have two threads on page 1 of this forum presently both of which you started. What do want? - World domination?
Don't double post, is is unnecessary.