Firmware decryption tool for OP-1
This tool allows the decryption of the OP-1 firmware. Especially the file
In that file every boot stream block with the flag
BFLAG_CALLBACK is encrpyted using the XTEA algorithm.
For every 24 byte block only the first 8 byte are encrypted and the remaining 16 bytes are unencrypted.
gcc -o decrypt decrypt.c
Key, input file and output file needs to be provided as parameters
decrypt [key] [input] [output]
The key is a 16 byte in length and must be provided as 32 character hexadecimal string on the command line.