Tutorial:Mounting the Ramdisk of IPSW in Betas 4-7

From The Apple Wiki

How to mount beta 4-7 ramdisks

First unzip your IPSW, and take out the ramdisk file. It will be around 18MB. Then put it on your desktop.

In Terminal...

Launch /Applications/Utilities/Terminal.app

Then type the following:

cd Desktop
echo `hexdump -s12 -n4 -e '"%d\n"' ramdisk-should-just-be-a-bunch-of-numbers.dmg ` / 32 | bc

A number should appear. For example, in the case of beta 5, it would be 604800.

So you will type the following command now:

dd if=ramdisk-name-aka-a-bunch-of-numbers.dmg of=ramdiskb5.dmg bs=32 skip=1 count=**NUMBERS-GO-HERE** conv=sync

After this, you will have a file called ramdiskb5.dmg on your desktop. Just double click this file and it should mount fine. Example: Beta 5 Ramdisk

Macintosh:~ xxxxxxxxx$ cd /Users/xxxxxxx/Desktop/iPhone1,1_2.0_5A274d_Resto

This is where I unzipped my IPSW. I was a bit sloppy and did it the quick but annoying way, and accidently deleted some letters. But my point is that this is a folder name. You'd probably be better off just unzipping the ramdisk to your desktop rather than to a folder)

Macintosh:iPhone1,1_2.0_5A274d_Resto xxxxxxx$ echo `hexdump -s12 -n4 -e '"%d\n"' 018-3615-6.dmg ` / 32 | bc 604800

This gets me the number I need for the next step / 604800 this is the number I need for the next command

Macintosh:iPhone1,1_2.0_5A274d_Resto xxxxxxxx$ dd if=018-3615-6.dmg of=ramdiskb5.dmg bs=32 skip=1 count=604800 conv=sync
604800+0 records in
604800+0 records out
19353600 bytes transferred in 5.721840 secs (3382408 bytes/sec)

This made my ramdisk mountable At this point, the decrypted ramdisk was on my desktop, ready for use

External Links

source: ChronicDev User Wiki [Archived 2008-07-09 at the Wayback Machine]