Savegames, as well as almost all other files, are encrypted using some crypto magic. The keys were found and now there are some tools to decrypt and recrypt the savegames called Segher's Wii.git.
To compile them, you need to also compile OpenSSL, add the
include-directory of OpenSSL to the search path for gcc and
also point the
ld to the compiled libcrypto.a.
After that, find the 3 interesting keys on HackMii, which are
Create a directory
~/.wii and put the 3 keys in binary form in there. (No text file with the values as numbers
and letters but binary files with exactly 16 Bytes per file. Use
ghex2 or such.)
If everything is correct, you can uncompress savegames data.bin using
tachtig and recompress them using