unsigned code loader for Amlogic bootrom

• https://github.com/frederic/amlogic-usbdl.git
• https://github.com/repk/gxlimg.git

Changes

• 22.07.2023
• add support for usb password protect
• fix some script

Disclaimer

You will be solely responsible for any damage caused to your hardware/software/warranty/data/cat/etc...

Description

Amlogic bootrom supports booting from USB. This method of boot requires an USB host to send a signed bootloader to the bootrom via USB port.

This tool exploits a vulnerability in the USB download mode to load and run unsigned code in Secure World.

Supported targets

• A95x Max secured
• Probably work with all s905x2 box.

Scripts

• all.sh
• Dump bootloader+dtb, convert dtb to dts, dump efuse/sram extract asekey and iv,decrypt bootloader.
• All files be in dump_all dir.

Usage

Box must be in usbdl mod. To put box to usbdl mod with toothpick in AV hole on box push button and connect box with USB-A to USB-A cable with PC, keep pressed (10sec) after connect usb cable with pc.

• git clone https://github.com/Raxone/amlogic-usbdl_s905x2.git

• cd amlogic-usbdl_s905x2

• If board usb password protect, put password file in password folder,and rename to password.bin

• chmod +x -R . -fix permission.Command is with point

• ./scripts/all.sh

• All files be in dump_all dir.

• If board in nonsecured mode

• Only dump boot.bin dtb.bin bootloader.bin efuse.bin and extract dtb.bin to dts.

• If board in secured mode

• bl2aeskey -Bootloader(BL2) aeskey used for decrypt bootloader.

• bl2aesiv -Bootloader(BL2) initialization vector(IV)used for decrypt bootloader.bin.

• bootloader.bin -Dumped main bootloader from box(BL2,FIP,BL3.1,BL33(U-boot)).

• bootloader_dec.bin -Decrypted bootloader.bin

• dtb.bin -Device tree blob binary

• dtb_dts -Device tree blob txt

• root_rsa_keys.sha -sha256 of rootkeys used for encrypt booloader.

• pattern.secureboot.efuse -pattern burned in efuse from manufacturer to enable secureboot

• Extract bootloader with gxlimg to part (bl2,bl30,bl31,bl33_u-boot) folder image.

./amlogic-usbdl <input_file> [<output_file>]
    input_file: payload binary to load and execute (max size 65280 bytes)
    output_file: file to write data returned by payload

Payloads

Payloads are raw binary AArch64 executables. Some are provided in directory payloads/.

License

Please see LICENSE.