Different Ways to Root Firmware

Magisk

Magisk is a suite of open source software for customizing Android, supporting devices higher than Android 6.0.
Some highlight features:

MagiskSU: Provide root access for applications
Magisk Modules: Modify read-only partitions by installing modules
MagiskBoot: The most complete tool for unpacking and repacking Android boot images
Zygisk: Run code in every Android applications' processes

Download Link: https://github.com/topjohnwu/Magisk/releases

Magisk Patcher

Patches a boot.img on a Windows PC instead of Android.

Download Link: https://github.com/affggh/Magisk_patcher/releases

Patch Magisk boot image on a Linux PC
https://github.com/vn-ncvinh/magisk-boot-patcher
https://github.com/daboynb/magisk_for_linux

APatch

The patching of Android kernel and Android system.

A new Kernel-based root solution for Android devices.
APM: Magisk module like support
KPM: Kernel Patch Module support. (Allow you to inject any code into the kernel, Kernel function inline-hook and syscall-table-hook is available)
APatch relies on KernelPatch

The source code for both APatch UI and APM has been copied and modified from KernelSU.

Supports

Download Link: https://github.com/bmax121/APatch/releases

All the rooting methods require the firmware boot.img to work.

Support