|
The iPhone Wiki is no longer updated. Visit this article on The Apple Wiki for current information. |
Preventing Baseband Update
Step 1: Swap Ramdisks
Open the IPSW (with your favorite ZIP utility). Replace the Restore Ramdisk and the Update Ramdisk names with each other.
Step 2: Edit options.plist
- Unpack custom IPSW
- Decrypt Restore Ramdisk using xpwntool and mount it
- Navigate to /usr/local/share/restore
- Edit options.plist on the restore ramdisk
(Ignore the SystemPartitionSize in your plist file and leave it)
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>UpdateBaseband</key>
<false/>
</dict>
</plist>
- Reencrypt the restore ramdisk
- Repack the IPSW
- Prepare device for custom firmware using redsn0w
- Restore IPSW to iTunes in pwned DFU Mode
You must load a patched iBSS/iBEC for this to work. Using an original IPSW will not work, because redsn0w's pwned DFU Mode doesn't patch sigchecks in iBSS.
TinyUmbrella/Cydia Method for iPhone 4 (Doesnt work on iOS 4.2.1)
The iPhone 4 requires a signature from Apple in order to update the baseband. Pointing the hosts file to Saurik's server or running TinyUmbrella will allow this request for signature to be ignored, thus preventing a baseband update.
Warning : This might only work if Cydia/TinyUmbrella accepts the latest firmware SHSH
- Edit the hosts file and add the line "74.208.10.249 gs.apple.com" without the quotes, or run TinyUmbrella after saving the firmware's SHSH
- Use the "Restore" button in iTunes to update.
Custom Firmware wont work with TinyUmbrella/Cydia Method
