WZR-HP-G300NH2 migrate from OpenWRT to Buffalo factory firmware

參考文件
1: WZR-HP-G450H and TFTP original firmware

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Steps:

1. Download the openwrt source files and look for buffalo-enc.c, buffalo-lib.c, and buffalo-lib.h.

2. Open buffalo-enc.c and add the line to the top:

#include "buffalo-lib.c"

3. Use whatever C/C++ compiler you want, but I used gcc:

gcc -o buffalo-enc.prog buffalo-enc.c

4. Now you have the decryption program, but you'll need to strip off the first "start" section of the firmware using a hex editor. I used wxhexedit 0.22 (0.21 has a bug that disallows saving truncated files). You must highlight and delete the first 208 bytes of the firmware file up to the second "start" word in the file.

5. After saving this, run buffalo-enc.prog -d -i wzrhpg450h-pro-v24sp2-20025.enc -o decrypted.bin

6. This will produce feedback text in your terminal indicating the decryption was successful.

7. You may now use the Openwrt (or any firmware flash gui running from your router) and it won't complain of an invalid firmware image.