N1200 How To Extract Or Recreate Thecus Firmware

Thecus supply encrypted firmware updates for their devices. It may be useful or necessary for you to extract this to investigate or manipulate its contents. To do this you will need to have openssl installed on a Linux machine. Currently the only place that it is possible to download firmware for the N1200 from is the Thecus beta downloads area.

Thecus have encoded the updates using openssl with the DES algorithm using 578991a8c84a5b0d as the password.

Decrypt Firmware
After downloading N1200_FW_1.00.08.3.bin for example, run the following command:

openssl enc -d -des -in N1200_FW_1.00.08.3.bin -out N1200FW.1.00.08.3.tar.gz -K 578991a8c84a5b0d -iv 0 -nosalt -nopad

This will leave the N1200FW.1.00.08.3.tar.gz file in your current directory which you can extract with:

tar -xzf N1200FW.1.00.08.3.tar.gz

Re-Encrypt Firmware
If you have assembled a custom update into the file MY_UPDATE.tar.gz run the following command to encrypt it:

openssl enc -e -des -out N1200_FW_1.00.08.3.bin -in MY_UPDATE.tar.gz -K 578991a8c84a5b0d -iv 0 -nosalt

You will now have your modified update in the N1200_FW_1.00.08.3.bin file in your current directory.