After unlocking the bootloader on my S10e I was unable to flash an unofficial Lineage OS 17.1 (Android 10) ROM to my device. I was originally on the stock AT&T ROM which STILL (January 2021) hasn’t been updated to Android 10. Most other carriers have released Android 10 for their S10 devices but AT&T not only is shipping devices with fully locked bootloaders but also aren’t supporting their customers with updates. With the power of modern technology and a little ingenuity we can right these wrongs.
First you’ll need an unlocked bootloader so you can flash your device with Odin. I was able to purchase an unlock for my S10e from SamPWND (read my article here) but if you already have an unlocked bootloader you’re ready to flash.
Two tools are required for this update process. Frija for downloading the updated stock Android 10 ROM and Odin3 to flash your device in download mode.
An Android 10 Custom Rom requires your device to already be on Android 10 to flash it successfully. Since AT&T hasn’t released a version of Android 10 I used Frija to download a clean ROM. I needed to use the SPR (Sprint) code in CSC which specifies the carrier. Check for updates, then download. Frija will decrypt the update so you can use it with Odin.
Once you’ve downloaded the update unzip it somewhere. You will have a few files that match the input fields in the Odin3 tool. Put your device into Download Mode and set each of the fields to their matching file from the update. Even the BL field. This will NOT relock your bootloader. You can flash TWRP or a custom recovery after you have verified you can boot into Stock Android 10.
Flash and Wait. Then your device should reboot into Android 10!
Some said it was impossible. Others dared to try. I dared to spend $100 and download a sketchy USB Redirector software to have someone else run their custom tool remotely to unlock my device. I had the resolve. I dared to swipe my credit card.
It’s no secret that Samsung devices have shipped with permanently locked bootloaders on most US carriers for many years now. I recently purchased a used S10e SM-G970U ATT and was unfortunately reminded of this. Somehow I had forgotten what a pain it was to unlock these things before my purchase. After some research when I found the OEM unlocking feature in Developer Options was missing in Android. Some more research later I learned that unlocking is in fact possible. Possible if you have the means. A functional exploit for S10, S20, and Fold/Flip devices does in fact exist to unlock the bootloader but it is private and proprietary. I purchased an unlock for $100 flat from https://www.sampwnd.com/ and it worked great. Hopefully this exploit is released to the public in the future but this is out best shot currently.
So I provided my DID adb shell getprop ro.boot.em.did and paid my hundred bones. Then I waited for a Discord message. They can either contact you with Telegram or Discord it’s up to you. After getting a message to download some software called usbredirector-customer-module.exe I connected to their session with my device in Download Mode and within 10 seconds my device rebooted with an unlocked bootloader.
Have you ever wanted to access data from an application that doesn’t provide a Public API? Well I’ve got great news. That application is getting its data from somewhere. You just need to find out how to plug into it! This process is called Reverse Engineering (Or hacking if you want to pretend you’re really smart) a Private API. I will document some tips and useful tools that will help you reverse any Private API from any application on any platform.
There are a hanful of tools that can be used to complete this task. Windows 10 was my platform of choice for working with the data so I’ll be sharing what I used on here.
Fiddler: Fiddler is an HTTP/HTTPS Proxy that can be used to intercept and decrypt SSL/HTTPS traffic. This application is also useful for replaying requests, creating custom request, and exporting a request as cURL to be converted into Python 3. Fiddler is free to use, just sign in with your Google Account! Make sure you install the certificate and enable HTTPS mode so you don’t miss any requests. https://www.telerik.com/fiddler
MitM Proxy: Man in the Middle Proxy is a great way to read data from Smart Phone Applications. This is what I used to get all the data I needed for my API reversal. Simply download the executable from https://mitmproxy.org/ to start up a server (disable your firewall or open port 8080) and then enter your PC’s IP address into the Proxy Server settings of your Phones WiFi settings. After that navigate to http://mitm.it/ on your Phone and install the provided certificate. Follow the provided instructions on http://mitm.it/ and start sniffing!
Create a text document to save all your finding and especially any useful URL endpoints you find. Having your information organized will help to ensure that you don’t waste time on the same thing twice or need to proxy your device over and over again to find what a request should look like.
Long time no see iOS/Android enthusiasts. I wanted to share a useful app I created to automated the process of running checkra1n for arm64 (Android Phone/Tablet) in TWRP (Team Win Recovery Project). This is a fully open source program (excluding the checkra1n binary) licensed under Zero Clause BSD. View it on GitHub here.
TWRP has a built in functionality to queue commands for the next recovery boot. These commands are located in /cache/recovery/command which is just a text file that TWRP reads. This is the same functionality that allows Over The Air (OTA) updates for custom ROMs to boot and reflash themselves.
Using this queue system the checkra1n TWRP app copies an Open Recovery Script (flashable .zip) to /data/checkra1n/checkra1n.zip and boots to recovery by invoking reboot recovery. The included checkra1n.zip then executes and boots back to system reboot system after the checkra1n log message of [*]: All Done is received.
This will not increase the comparability of checkra1n for Android devices but my 2015 Nexus 5X and 2018 Mi Mix 3 both run this application flawlessly. If you were already using your Android device to run checkra1n this should make things easier for you as you don’t need to interact with a shell at all on invoke/remember commands.
To flash the .zip within TWRP without running the app, which is useful if you leave your Android turned off until you need it for a retether, you can find the flashable Open Recovery Script in /data/checkra1n/ and flash it from the Install menu within TWRP.
Happy jailbreaking! (please report bugs on the Github Bug Tracker)
Note the location you downloaded the file to. You will need to know the absolute path the file is located so you can execute it from a terminal command line.
Once you have the file downloaded boot your Android phone into Custom Recovery. Running the tool from Custom Recovery instead of directly inside Android you don’t need to worry about a conflict between different processes fighting over the USB controller. I wasn’t able to run checkra1n from a fully booted Android 10 but I was able to run it from Custom Recovery! Your luck may vary but Custom Recovery is the most reliable option.
Open a Terminal in Custom Recovery (TWRP 3.3.1-17 was used in my video) and change directory to where you saved checkra1n
Next we need to add the execute flag to the binary so it can be run as a program
chmod +x checkra1n
Finally we can run checkra1n from Android
./checkra1n -c -v
Connect your iOS device using your USB-C to USB-A adapter and your Lightning cable.
Now we need to manually enter DFU mode on our iOS device. This is done differently on different devices so if you are unsure just look up “How to put iPhone X into DFU mode” replacing iPhone X with your model and you should find some button combinations to enter DFU.
If you have successfully put your iOS device into DFU and it is connected to your Android Phone running checkra1n the program should recognize the DFU mode USB device and run the exploit!