Hi!
This is pretty good! I could not imagine that this would happening here...
I am working in the translation of Ninokuni DS game, and it has a part of wifi connection where you can download a file with some "magic news" and activate new missions and objects. I have been able to get the decrypted data by finding the RC4 (the symmetric key algorithm used) encoding / decoding asm routine. Since all the data to be sent must be encrypted and all the data received must be decrypted and the same algorithm is used for both operations it was easy to dump everything. It was then when I found this post... xD
I have already modified DeSmuME to dump automatically all the data that pass through the RC4 routine into an external text file (it's data, not package), but as the address of that routine change with every game it only works with Ninokuni.
Now I am working in a more compatible modification: dump all the packets that are sent and received into PCAP format (Wireshark format). The problem is that it would dump the data encrypted. For this reason I want to do a program to patch automatically every game, including games with ARM9 / overlays compressed (as I have already done it for the Ninokuni translation it is easy).
Another thing I would like to try it's to find the RC4 routine automatically by an external tool, pass that address to DeSmuME (for instance as a terminal argument) and use the first method of dumping data. In this way it would be no need to use NO SSL patches (for instance in Ninokuni, for the downloading server it must connect with HTTPS otherwise it will never connect).
If I finally get it working, it would be so easy to get logs, as easy as play to any game in DeSmuME.
Let's do it!