IBooty

iBooty is a utility created by iH8sn0w to aid in jailbreaking iPod touch 3G and iPhone 3GS (new bootrom) devices. The jailbreak is tethered. It has been reverse-engineered and is being ported to Linux. See [1] for information on booting your tethered device on Linux.

This application has been ported along with Payload Pwner to Mac OS X 10.4+ under the name Pneumonia.

Also there's a application which includes Payload Pwner and iBooty called Nephron. (available @github)

"Boot it!" Function

Reverse-engineered by dra1nerdrake (helped with finding one command) and maintainly by Fallensn0w, iBooty uploads the payload (nothing more than a pwned 3.1.2 iBoot), then uploads 4.0 iBEC and jumps to it. It resets the connection and then uploads and sets up the device tree. Now it uploads and sets up iH8sn0w's logo. Finally, it uploads the kernelcache for iOS 4.0 and boots the device.

"Prepare" Function

Although I can not be sure yet, I believe that the program uploads the payload, then the 4.0 iBEC, and uploads and prepares the logo, which notifies you to begin the restore process.

Resources

There's a open-source version of iBooty by Fallensn0w available at @github