How to backup HTC EVO’s WiMAX RSA encryption keys
Now that you've confirmed the presence of the important WiMAX RSA encryption keys on your HTC EVO 4G, you're probably going to want to back them up and put them somewhere for safekeeping.
BooDaddy at the xda-developers forum is already a step ahead and has written a simple tutorial on how to backup those precious WiMAX keys whether your EVO is currently rooted or not. You can check out his write-up here.
If your EVO is rooted and you've got both BusyBox and a terminal emulator installed, though, then you can backup the keys straight from your phone. No computer needed.
You can use any terminal emu you want, but my personal favorite (and one of G&E's top 10 root apps) is Android Terminal Emulator, so that's what you'll see below.
Here's the QR code if you want it:
Backing up your EVO's WiMAX keys with Android Terminal Emulator is very simple.
Just open the app, type su, and hit Enter key. The $ sign will be replaced with a # sign.
sed -n '/BEGIN CERTIFICATE/,$p' /dev/mtd/mtd0 > /sdcard/rsa_OEM.key
and hit the Enter key. If it's too much typing, you can copy-and-paste it.
It will look like nothing has happened for a few seconds, and then you'll see # prompt again. Success!
Navigate to the root directory of your EVO's SD card (that's ASTRO you see in the screenshot at the top, but any file manager will do) if you want to double-check that the rsa_OEM key file is really there. Now you can store the file wherever you want and your WiMAX keys will always be safe.[xda-developers]