It doesn't matter how I exactly encrypt and decode files. I operate with file as a char massive, everything is almost fine, until I get file, which size is not divide to 8 bytes. Because I can encrypt and decode file each round 8 bytes, because of particular qualities of algorithm (size of block must be 64 bit).
So then, for example, I face .jpg and tried simply add spaces to end of file, result file can't be opened ( ofc. with .txt files nothing bad happen).
Is any way out here?
If you want information about algorithm http://en.wikipedia.org/wiki/GOST_(block_cipher).
UPD: I can't store how many bytes was added, because initial file can be deleted or moved. And, what we are suppose to do then we know only key and have encrypted file.
