Saurik Duplicates Apple’s Firmware Signing Server

##ICON_NAME## Saurik has developed a server that you can point your iTunes to and it will not only authenticate firmware versions that Apple no longer signs (allowing them to be installed) it also saves information during the authentication and will allow you to downgrade later if Apple doesn’t want you to. This blog post he wrote is a really good read, but it’s really long. Here’s a quick highlight but make sure you read the whole thing here:

To this end, I have constructed a server that duplicates the functionality exposed by Apple’s signature server, except using “on file” results rather than live requests.

All we need, then, is to make iTunes use it. Luckily, most operating systems also have the ability to locally define bypasses on specific hostnames through a file called hosts. Using this, we can redirect requests to Apple’s signature server to Cydia.

So, open the file C:\Windows\System32\drivers\etc\hosts (Windows) or /etc/hosts (Mac OS X) and add the following entry to the bottom of the file.

Now, when iTunes thinks it is talking to Apple, it is talking to Cydia instead. Doing this will allow iTunes to access signatures already stored by Cydia’s “on file” feature.

This server will also act as a cache for any SHSH blobs it hasn’t seen, acting as an intermediary to Apple’s server. This effectively registers your device with the “on file” mechanism, which means you can now enjoy the protections of being able to downgrade your firmware in the future even if you aren’t jailbroken.

This point should be stressed: even if you don’t jailbreak, and even if you never intend to jailbreak, you should consider using the new “on file” service.

Let’s say that Apple releases an OS upgrade in the future, you take it, and they break something important. Maybe they break your e-mail account, or your todo list. Your business is now crippled.

If only you could downgrade, right? Alas, Apple won’t let you anymore. That’s where the new signature cache server comes in: by doing your restores through this server you secure your ability to not accept upgrades from Apple if the need is dire.

Check out the full article HERE.

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  1. Very cool.

  2. what do you open that file with?

  3. Bravo bravo Saurik ur gr8 man. This is a big blow to apple and steve job who try to mess with our property. Dev team and Saurik is gr8.

  4. Just downgraded successfully from 3.1 to 3.0. Some issues, though; not possible to sync with 3.1 sync.. And it doesn’t look like my att signal is coming back on.

  5. How do you do it on a mac? The terminal will not allow me into hosts file

    • Go into Finder and into your computer. Then press Go -> Go to Folder, or press Shift+cmd+G. Then enter /etc. You will then be taken to where the folder of the hosts-file is located..

    • Run this command in Terminal:
      sudo /Applications/ /etc/hosts
      Then add the entry and save.

  6. read the full article it has some info on not having att signal. i hope it helps.

  7. What if I never backup my files on his server?

  8. im confused, im using a windows vista and i opened it but i got these examples. this means i should post that like this? Is it on the bottom of the local host or in the bottom of these examples??

    # For example:
    # # source server
    # # x client host

    ::1 localhost

  9. Steve Thompson says

    These guys are good! Great job!

  10. my computer will not let me save the new edited file.. i added that line to the bottom of the host document and hit save and it says that i do not have appropriate access to save.. i am the admin of the computer and have changed the privileges to allow “read and write” access… does anyone know why this is happening? Thanks.

  11. can i downgrade from 3.1 to 3.0?
    please let me know, thanks

  12. Hey, i have made the changes, but is there a way to make sure i did it right or at least know that it worked?

  13. Can anyone post a how to video for windows, I am not sure I did it correctly.

  14. does this still works? I need to upgrade an iPad 4 form ios 6 to ios 7, dont want the ios 8. thanks.

  15. I just tried this and it did not work.
    My host file reads:

    # Host Database
    # localhost is used to configure the loopback interface
    # when the system is booting. Do not change this entry.
    ## localhost broadcasthost
    ::1 localhost
    fe80::1%lo0 localhost

    What am I missing here? I pasted it below as suggested.


  1. […] J’ai pas tout lu, mais il a dupliqué le serveur d’Apple. A lire ici […]