7.6 KiB
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
Python 3.10.2 Make sure to check "add to path" option when installing.
A (preferably non samsung) Android 7-9 (possibly Android 10) device that is able to be rooted.
Optional
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
- Open your device's Settings and tap About phone or About tablet.
- Tap Build number repeatedly until you see a notification that reads "You are now a developer."
- Go back to the main System menu, then tap Developer options.
- Tap the toggle switch in the top-right corner to enable developer options (if it's not already enabled).
- Tap OK to confirm.
- Tap the USB debugging toggle switch.
- Tap OK to confirm.
- 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 chwon permission, this is negligible
Login as super user and clear any user environment variables active by including a hyphen after su 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
Open command prompt as adminstrator and navigate to extracted Downey 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
WIP 8/29/2022 - Should be finished within a day or two