SAR support on Android 10

[sztihamer]

Hijacker fails to show any networks with the latest version on LineageOS 17.1 on the Nexus 5.

Link to ROM:
https://forum.xda-developers.com/google-nexus-5/orig-development/rom-lineageos-17-1-nexus-5-hammerhead-t4039273
https://sourceforge.net/projects/hammerhead-lineageos/files/17.1/

Logs in this post and explanation why Hijacker won't work. Because of SAR (system as root):
https://forum.xda-developers.com/showpost.php?p=81807009&postcount=106

I have latest stable version of Magisk installed (20.3) but I guess tools are not loading nor the firmware is getting swapped with the Nexmon one.

[chrisk44]

System-as-root by itself has nothing to do with root access (that is, a su binary you can run to get a root shell). SAR is a Parition Layout as described here. This may make rooting more difficult (I wouldn't know, I haven't worked with it), but as long as you have found a way to root your device, somehow somewhere there should be a su binary that works.

Hijacker will call this binary, you will be asked whether you approve of this by your system/Magisk/whatever-your-rooting-solution-is, and Hijacker will have a shell with root access to run the tools it needs. As long as nothing goes wrong in the above procedure, Hijacker should work.

Now, a requirement for Hijacker to work is to have a custom firmware installed for your device's wireless adapter. I see from your logs that you tried to install it. The way Hijacker does that is simple (as it can be seen in the install() function in InstallFirmwareDialog.java, everything is done through a root shell):

1. You select where you want to install the firmware and the nexutil binary (I am assuming that these directories will be on the system partition).
2. The system partition is remounted as read-write.
3. The firmware and utility binary are extracted from the app and copied in the directories you selected.
4. The system partition is remounted as read-only.

That's probably where it all goes wrong in your case. I have no idea what has happened with SAR, but Hijacker might not be able to remount the system as read-write and write the new firmware to it. Or maybe the install directories are wrong, or the supplied firmware doesn't work on Android 10, or the specific command I used doesn't work for some reasom, or a thousand other things that can go wrong...

So what I propose is that you try to install the firmware by yourself and then try again.
Also, in the app's settings you will find a "Test Tools" option. If the tests pass, then I'm probably right, the problem is with the firmware installation. If they fail try running the commands manually, see what happens and tell me so we can work it out from there.

[sztihamer]

Testing tools is like it was before. Everything has a check mark except Kali chroot which is good.
Firmware Location says /system/vendor/firmware/fw_bcmdhd.bin

That is what I should replace and try again?

[chrisk44]

You should try to install the firmware manually. Find the firmware binary, find out where it is located in your device and replace it. Reboot the device and hopefully it will work.

[sztihamer]

Alright here's what I did and I failed miserably just like when I was messing with LineageOS 14.1. I replaced fw_bcmdhd.bin in /system/vendor/firmware/ and rebooted. That is where Hijacker detected the firmware. Is that location correct? Because after reboot I bricked Wifi and the the toggle went back to Off every single time I turned it on.

To fix I had to flash ROM in TWRP again and that fixed it but I am back to square one. I never had success with manual replacing only when Hijacker did it in the past.

[chrisk44]

Make sure you are using the correct firmware file and that you replace the original file with the new without changing the filename.

[sztihamer]

I took this:
https://github.com/chrisk44/Hijacker/blob/master/app/src/main/assets/fw_bcmdhd_4339.bin

And renamed it to fw_bcmdhd.bin, is that the issue? Does it make a difference if I rename the file?

[chrisk44]

You should rename it to fw_bcmdhd.bin and replace the original file with it. Also, place the nexutil binary in a PATH accessible directory.

[sztihamer]

Yep. That's what I did with the firmware. Copy and replace it in /system/vendor/firmware/ or delete and paste in new file. That didn't work.

[chrisk44]

Did you run the tools manually in a terminal? What happens then?

[sztihamer]

I tried to run nexutil from /data/data/com.hijacker/files and I got this:
system/bin/sh: nexutil: inaccessible or not found

[chrisk44]

nexutil must be in a PATH accessible directory and you can run it from anywhere you want. Run the test commands supplied by Hijacker.

[sztihamer]

Put nexutil in /system/bin and I get this now:
system/bin/sh: nexutil: can't execute: Permission denied

[chrisk44]

You need to chmod +x nexutil

[sztihamer]

chmod: nexutil: No such file or directory

[sztihamer]

Alright. I chmod 755 in TWRP and now I can run nexutil --help