/action_sprd_signer

Primary LanguagePython

Action SPRD image sign tool

我是**人

Action Workflows to sign image for Unisoc/SPRD device.

Introduce

As I know, two sign method are used by Unisoc. Please choose different signature methods based on your SoC model.

AVBTOOL METHOD

Warning

Avbtool method isn't yet tested. Try it at your own risk!

Workflow name: Sign image (avbtool)

Avbtool is a tool to read AVB2.0 (or avb1.0 support?) signed image and sign an image. Avbtool method means using avbtool to sign the image. Check here and here if you want to know how does it work.

For example, SC9832E/SL8541E uses Android Verified Boot 2.0 to sign and verify the image. It should use avbtool method.

Usually, if your device has vbmeta partition and it was not empty, you should use this method.

If you want to further confirm, you can check the header of your boot image and vbmeta image. The boot image uses common header (ANDROID! in the first 8 bytes) but vbmeta uses a different header (DHTB in the first 4 bytes) that avbtool can not read it correctly.

BSP SIGN METHOD

Workflow name: Sign image (Legacy)

I called it Legacy method before but that isn't correct. This method uses Unisoc's BSP sign tool to sign the image.

BSP sign method often uses on uboot, fdl1/2, etc., excluding boot and recovery image. But SC9820E/SL8521E uses this method to sign the boot image, including devices using Android 4.4 and Android 8.1.

I ain't sure, but if your device doesn't have vbmeta pertition or it was empty, you may need to use this method to sign your boot image.

If you want to further confirm, you can check the header of your boot image. The boot image uses DHTB for it's header instead of ANDROID! so that bootimg unpacker can't read it correctly (but magiskboot and AIK seems working normally!). Actually, ANDROID! has been moved backwards by 512 bytes.

How to use

You should provide boot\recovery image you want to sign. Original vbmeta image from your device is also needed if you are using avbtool method. DON'T REMOVE DHTB HEADER IN YOUR VBMETA IMAGE!

  1. Use Fork or Use this template to clone this reposity to your personal account image

  2. Upload your image to somewhere that can get the DIRECT LINK to your image. For example, I upload my image to this reposity and used "View raw" to get the link. image image

  3. Open the Actions tab and choose a workflow. Read the introduce to help you make decision. image

  4. Press Run workflow button, and fill in according to the above parameter description, then press Run workflow image

  • If you choose Sign image (Legacy), there's only one parameter you need to fill in.

image

  • But if you choose Sign image (avbtool), the number of parameters will increase to 5.

image

  • The fourth parameter may be confusing. You can read back the boot/recovery partition of your device correctly. The size of the output file is the value of this parameter. If you operate incorrectly, the size of the output file may change.
  1. Just drink a tea and wait for a while. After a few seconds, the signed image will be uploaded to artifact. You can download it right now and flash into your device! image