Saving your SHSH files

If you haven't already saved your SHSH files for 3.1.3, do so as soon as possible. You never know when it could come in handy.

If you were already jailbroken on 3.1.2 and had clicked Cydia's "Make my life easier" option, you probably have your hashes in Cydia's on-file system. Saurik tweeted recently:

In case anyone was wondering, every device (all 1.37 million of them) with an "on file" ECID now has a 3.1.3 SHSH saved in Cydia's database!2:39 PM Apr 1st via web

If you're not sure of having done that, or you bought a new phone, or otherwise know for sure that you don't have 3.1.3 hashes already, just download Firmware Umbrella (go to http://thefirmwareumbrella.blogspot.com). It runs on your Mac or Windows, and along with a local TSS server (Tiny TSS) allows you to save your device hashes for the firmware versions that Apple is currently signing. When you need to restore to one of those versions, and Apple has stopped signing them, you can set up TinyTSS on your local machine and bypass Apple's signature server to make your device eligible for the restore process.