Programs are designed to encrypt/decrypt files using the Blowfish algorithm in ECB mode.
make
./blowfish <key_file> <input_file> <output_file> <mode>The 1st argument <key_file>: 256-bit file containing the key;
The 2nd argument <input_file>: name of the file to be encrypted/decrypted;
The 3rd argument <output_file>: name of encrypted/decrypted file;
The 4th argument : mode of program working (1 - encryption; 2 - decryption).
Program adds 1 byte to the beginning of file - a number of appended zero bytes.
You can generate a random key like this
Original file data:
Launching the program:
Cipher data:
Highlighted in blue: number of appended zero bytes (block padding up to 64 bits);
Highlighted in red: cipher data;
Highlighted in purple: encrypted end-of-file character;
Highlighted in green: encrypted appended zeros.