Danacus
/
cdm-tools-how-to
mirror of https://CDM-Project.com/cdm-tools/how-to.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
11 Commits 1 Branch 0 Tags 101 KiB
Go to file
TPD94 131746ceef Update README.md 2022-08-31 11:16:00 -04:00
README.md Update README.md 2022-08-31 11:16:00 -04:00

README.md

Purpose of this project

Hello everyone! Hope all is good. I've spent the past few months scouring pages just to try and get decryption keys for widevine content. There was no clear instructions on the internet and the instructions that are there need pieced togther for a proper result. What I've tried to do is condense these fragments down to a cohesive guide for people to follow. If you have any questions feel free to message me on here, my reddit or discord, Contact informatoin can be found on my profile.

Prerequisites

I used all the mentioned tools on windows 10 x64

Golang

Python 3.10.2 Make sure to check "add to path" option when installing.

ADB Minimal Install

A (preferably non samsung) Android 7-9 (possibly Android 10) device that is able to be rooted.

Tools used

Dumper

Downey

Optional

YT-DLP

MP4 Decrypt

ffMPEG

Android device I used

Truewell T95 S1 Pre-rooted, around $30 USD, multiple user success of dumping keys (myself included), good for those who don't have a spare android.

IF YOU DO USE YOUR OWN ANDROID DEVICE YOU MUST INSTALL MAGISK AND THE FRIDA-SERVER MODULE

You can find the installation instructions for magisk here and the frida module here.

Step 1: Preparing CDM

Connect to your android device via ADB, on the T95 this is enabled by default over wifi. Other devices may vary.

To enable ADB / USB Debugging follow these steps

  1. Open your device's Settings and tap About phone or About tablet.
  2. Tap Build number repeatedly until you see a notification that reads "You are now a developer."
  3. Go back to the main System menu, then tap Developer options.
  4. Tap the toggle switch in the top-right corner to enable developer options (if it's not already enabled).
  5. Tap OK to confirm.
  6. Tap the USB debugging toggle switch.
  7. Tap OK to confirm.
  8. The next time you plug your device into a computer, you'll receive a prompt asking if you want to authorize USB debugging for that computer. Tap OK to confirm.

You may now connect to your device

adb connect <device-ip-address> or if using USB adb devices

On your device you should receive a notificatoin to accept the adb connection, checkmark trust this device and then click allow.

IF YOU HAVE MAGISK-FRIDA MODULE INSTALLED YOU MAY SKIP TO THE NEXT STEP

Let's go ahead and push frida-server to the Android device, for the T95 S1 I used Frida-Server 15.1.17 for android. Unnzip the xz file and extract Frida-Server file.

Change directory to where you extracted the file and enter the command adb push frida-server-15.1.17-android-arm /sdcard/

Once it has been pushed open up a shell with adb shell

Move the server to the tmp directory mv /sdcard/fridaserver-15.1.17-android-arm /data/local/tmp/

You may get an error about chown permission, this is negligible

Login as super user and create a new enviroment su -

Give execute privileges to frida-server chmod +x /data/local/tmp/fridaserver-15.1.17-android-arm

Start the server /data/local/tmp/fridaserver-15.1.17-android-arm

When you start the server command prompt will hang, this is normal and means the program is running, do not close out and continue to step 2

Step 2: Extracting the CDM

If you would like to check if frida-server is running connect via adb to your device in new command prompt like in step one, then use adb shell and then su and then ps | grep frida this should show you the process running, if it does not something went wrong

Download and extract Dumper

Open a new command prompt as administrator and change directories to the newly extracted folder and run pip3 install -r requirements.txt and once that's finished, start the program with python dump_keys.py

Now play some widevine encrpyed content. I suggest using https://bitmovin.com/demos/drm playing over google chrome.

Side note: on the T95 S1 I had to stop and start dumper a few times and rebooted the device a few times, sometimes it does take some effort for it to dump the keys

Once you have played the content your keys should be dumped in the dumper folder under /key-dumps/your-device-keys/xxxx/xxxxxxxx/ and should be named client_id.bin and private_key.pem

Make a copy of these for safekeeping wherever you like but DO NOT LOSE THEM

You can now close out of running frida server if you are running it over adb, you may also close dumper once you have verified successful dumping.

Make sure to have file extensions visible on windows, this can be turned on by searching "show file extensions" in the windows search bar.

Now we will rename these files, clent_id.bin to device_client_id_blob. and rename private_key.pem to device_private_key. The periods on the end is intentional as windows likes to keep file extentions, please make sure to have this exact or it will cause errors with downey! Only rename with windows, using a program such as text editor and saving under all files will still corrupt the data!

Step 3: Obtaining decryption keys

Download and extract Downey

Open a new command prompt as administrator and change directories to the newly extracted folder

Build Downey with command go build -o downey.exe -a main.go once this is finished you should see downeye.exe in your Downey folder

Copy the device_client_id_blob file and device_private_key file to the Downey folder.

Open Firefox or Chrome and navigate back to https://bitmovin.com/demos/drm and open web devoloper tools (ctrl+shift+c) and click on the network tab

Play the video on the site, then in the filter urls type in method:POST and under the domain look for the licensing server, in this case it's https://cwip-shaka-proxy.appspot.com/ right click on this value and copy value -> copy post data and paste this somewhere safe for now.

Next we need the MPD file, under the filter url section in the network tab now we are going to filter for MPD one result should show up for 11331.mpd downoad this by double clicking or copying and saving. Rename this file to manifest.mpdand place it in your Downey folder

Now we have everything we need, let's go ahead and run downey with downey.exe --lic-server "https://cwip-shaka-proxy.appspot.com/no_auth" if everything goes successful you should get the decryption keys for the video, so for bitmovin i received

Decryption keys:
ccbf5fb4c2965be7aa130ffb3ba9fd73:9cc0c92044cb1d69433f5f5839a159df
9bf0e9cf0d7b55aeb4b289a63bab8610:90f52fd8ca48717b21d0c2fed7a12ae1
eb676abbcb345e96bbcf616630f1a3da:100b6c20940f779a4589152b57d2dacb
0294b9599d755de2bbf0fdca3fa5eab7:3bda2f40344c7def614227b9c0f03e26
639da80cf23b55f3b8cab3f64cfa5df6:229f5f29b643e203004b30c4eaf348f4

And there you have it! decryption keys for all versions of the video and one for the audio.

Optional: How to download, decrypt, and merge Bitmovin video and audio

Downloading

Download YT-DLP and place in a new folder or a folder of your choice.

Open a new command prompt as administrator and change directories to the folder you've placed yt-dlp.exe

Go back to https://bitmovin.com/demos/drm and open up the web devoloper tools (ctrl+shift+c) and click on the network tab.

Play the video on the site, then in the filter urls type in MPD like in step 3.

Copy the url value from the search result. You can do this by: Right click -> Copy Value -> Copy URL In this case it should be https://cdn.bitmovin.com/content/assets/art-of-motion_drm/mpds/11331.mpd

Now in the command prompt you have opened execute the command yt-dlp.exe --allow-unplayable https://cdn.bitmovin.com/content/assets/art-of-motion_drm/mpds/11331.mpd

This should download two files in your yt-dlp directory, an encrpyted mp4 video file and an encrypted m4a audio file. For ease I have renamed these encrypted.mp4 and encrypted.m4a

Decrypting

Download and extract MP4 Decrypt

Open a new command prompt as administrator and change directories to the MP4Decrypt bin folder.

Place your encrpyted.mp4 and encrypted.m4a files in this bin folder as well

Decrpyt the video by using mp4decrypt.exe --key xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx inputfile.mp4 outputfile.mp4 where the key in this case would be one we extracted earlier, inputfile.mp4 being the encrytped.mp4 file we downloaded earlier and outputfile.mp4 can be named whatever you choose, I will be using decrypted.mp4 so for this instance it would be mp4decrypt.exe --key eb676abbcb345e96bbcf616630f1a3da:100b6c20940f779a4589152b57d2dacb encrypted.mp4 decrypted.mp4

Decrpyt the audio by using mp4decrypt.exe --key xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx inputfile.m4a outputfile.m4a where the key in this case would be one we extracted earlier, inputfile.m4a being the encrytped.m4a file we downloaded earlier and outputfile.m4a can be named whatever you choose, I will be using decrypted.m4a so for this instance it would be mp4decrypt.exe --key eb676abbcb345e96bbcf616630f1a3da:100b6c20940f779a4589152b57d2dacb encrypted.m4a decrypted.m4a

You should now have two playable files, the video decrypted.mp4 and the audio decrypted.m4a now it's time for the final step .

Merging

Download and extract ffMPEG

Open a new command prompt as administrator and change directories to the ffmpeg bin folder.

Place your decrpyted.mp4 and derypted.m4a files in this bin folder as well

In command prompt issue the command to merge the two streams ffmpeg.exe -i decrypted.mp4 -i decrypted.m4a -vcodec copy -acodec copy bitmovin.mp4

Congrats, you now have a playable widevine audio/video file!