Bootloaders

To reverse egineer a bootloader, QEMU and GDB can be used.

For example, if you have a bootloader of DOS/MBR boot sector type, you can use the following command to run it in QEMU:

qemu-system-i386 -drive file=bootloader.bin,format=raw

To debug the bootloader, you can use the following command:

qemu-system-i386 -drive file=bootloader.bin,format=raw -s -S

Then, you can connect GDB to QEMU using the following command:

gdb
target remote localhost:1234