From the bootloader, we can dump the file vinda in the ext4 partition at emmc2:6.
sunxi#ext4load
ext4load - load binary file from a Ext4 filesystem
Usage:
ext4load <interface> <dev[:part]> [addr] [filename] [bytes]
- load binary file 'filename' from 'dev' on 'interface'
to address 'addr' from ext4 filesystem
sunxi#ext4load mmc 2:6 0 vinda
Loading file "vinda" from mmc device 2:6
16 bytes read
sunxi#md 0 4
00000000: 5b415243 51454346 54505042 525f5655 CRA[FCEQBPPTUV_R
The string of bytes can be XOR’d with the byte 0x37 to gain the root password.
For my device, the decrypted password is tevlqtrfuggcbahe.
uname -a
Linux rockrobo 3.4.39 #1 SMP PREEMPT Wed Mar 25 20:47:59 CST 2020 armv7l armv7l armv7l GNU/Linux