newbie question about BootMii

This seemed like a more appropriate place to ask this than the general forum, but sorry if this is the wrong place... Also, nothing I am about to say--to my knowledge--is against any rules here, but if it is please tell me and I will kindly not ask again.

I read that BootMii can't be used on the newer systems due to the fact that Nintendo has the key that validates boot2 stored in boot1, which is written only at the factory and cannot be rewritten. So, any changes to boot2 would make its checksum (for lack of a better term on my part) no longer match that static key in boot1.

But...Nintendo updated boot2. Does that mean that they somehow wrote it in such a way that they could make it end up having the same checksum to match boot1? Or, am I way off in assuming that the static data in boot1 is a checksum at all? I'm a programmer on a number of other business systems, so I can understand some of this without much difficulty. But...if Nintendo could rewrite boot2 and make it work...then can't TT do it too?

I know, I know, if it was that easy why don't I just go help them out...but this actual thought process just struck me with regards to reading here about the boot2v4 update. I'm just curious if my logic is waaaaay off base or if I'm pretty close.

Again, sorry if this is dangerously controversial. I will gladly edit away this message if an admin directs me to do so! :)

Quote
Koohiisan
But...if Nintendo could rewrite boot2 and make it work...then can't TT do it too?

They do. The boot2 update doesn't disable BootMii, it just removes it until BootMii is reinstalled.

If you're referring to how Nintendo did this for Wii's with a newer boot1, then you're overlooking the fact that Nintendo doesn't need the exploit in the old boott1 like TT does to updated boot2. Why? Because they're Nintendo and they have all the keys.



Edited 1 time(s). Last edit at 12/19/2009 02:16AM by Arikado.

Ah, I see... So it's not so much that Nintendo matched one static existing key in boot1 as much as it is that they just pulled another, previously unknown key or matching system out of their hat and used it. So it really isn't as simple as there being one key in boot1 and whatever boot2 is needing to match it. Boot1 is now smarter. Bummer.

I hope they can get an alternate method going, since I as many others are stuck with the new boot1.

Thanks for the info.

Here's a bit of clarification:
Before starting boot2, boot1 verifies boot2's digital signature. Older versions of boot1 had a bug in this routine called the Trucha or signing bug that allowed you to make up most of the signature, calculate the rest in a very simple way, and still have it be considered valid. This is how a boot2 with BootMii in it is considered valid and booted. Newer versions of boot1 lack this bug.