This is my first Mac OS X reversing tutorial. Target is You Control Desktops, which revealed itself a very nice target to reverse.

Download the files below and I hope you learn something from it.
There’s no interest whatsoever in piracy, but only in learning and improving things. What you do with this information is YOUR responsability.

The keygen (and decrypt.c) make a nice example of OpenSSL API usage. Keygen is non working. It compiles and does everything, but it will generate wrong checksums due to a small error created on purpose. You will need to fix it if you really want it to work 😃.

fG!

Available files:
you-control-desktops-tutorial.txt
keygen.c
Decrypt.c
unobfuscate.txt
data.txt

Update: Rename unobfuscate.txt to unobfuscate.pl after you download it or run with perl unobfuscate.txt.

Update 2: Compile keygen and decrypt with -lcrypto gcc option to link against OpenSSL libraries.

Update 3: While trying to keygen PTHPasteboard found a bug with BIO_get_mem_data because it doesn’t NULL terminate. So garbage was written to the licence file.
Grab the updated version (you still need to fix the on purpose error): keygen-youcontrol.nonworking.c.