Readcd

From Free60

Taken from readcd.txt

Not quite a part of XeLL, but might be useful: a "fixed sector reader".

The code is a bit quick&dirty, but does the following:

- load constants
- open tray using SMC

- delay a bit
- issue READ(10)-command,
- on error: request sense, loop
- read ~128k starting at LBA 0x20 to 0x1310000
- jump there

So to actually use this for a live cd, you need the following:

- prepare a CD with:
 - XeLL (patched to start at 0x1310000) at LBA 0x20 (usually the first file on CD)
 - the kernel, named "vmlinux" in the root of the CD,
 - the kernel must contain an initramfs to load the rootfs,
 - the initramfs must mount the CD, and pivot_root (or whatever) in there.

Then, launch the usual exploit code, but don't upload XeLL but instead this binary. It will eject the tray. Put in your linux CD. Close the tray, and it will launch XeLL. XeLL will launch vmlinux. from disc, and the kernel will run.

The readsector.S is position independent code, so just link it wherever you want. Oh, and yes, this code is "small enough" for what you are all waiting for.

Have fun ;)

- tmbinc

[edit] Building readcd

0. retrieve the xell code see XeLL step 1.

1. cd readcd

2. gcc -c readsector.S

3. objcopy -O binary readsector.o readcd.bin

These steps assume you are running this on your 360 otherwise you would need to use the cross compiler.