How to rescue an encrypted root filesystem?

[Derek Tattersall]

Well, I screwed up.

I tried to upgrade from f10 to f11, and it seems to have failed. It gets 
partway through the boot up and throws a bunch of errors regarding 
missing libraries. I would like to rescue some data off of the disk 
before I reformat it and try again, however I chose the encrypted file 
system option when I installed f10 originally.

So, I boot the machine with the f11 live cd, and that works, but how do 
I mount the hard disk? What encryption method did f10 use by default 
when I set up the disk originally? blowfish, aes? What set of arcane and 
cryptic commands do I have to use to mount the hard disk within the live cd?

I backed most everything up before I tried to upgrade, but there still 
some things I would like to recover if I can. It's no huge loss if I 
have to reformat and start over, but I'd still like to try to get some 
stuff off of the hard disk.

Thanks.

Derek Tattersall