Exercise 4-5: Kali Linux ARM chroot

You’ll begin with the SD card from a previous exercise. In this example, we are using the image from the previous exercise (Exercise 4) — our custom build. First, install qemu cross compiling tools and related tools into Kali:

Let’s make a /mnt/sd directory to keep our directories we’re working on organized:

Pick up your /dev/sd drive assignment by inserting the Pi’s SD card (ours is /dev/sdc). Your USB-SD adapter makes a difference. We are going to pick up all the physical drive mounts in one shot.

Did you notice how all the Raspberry Pi’s SD card directories are now mapped on your system under /mnt/sd?

Mount up all ‘special filesystems’ under /mnt/sd. Notice that we will be overriding mount options from /etc/fstab on some that are already mapped with the -o option:

Let’s pull the emu cross-compiling tools over. We need these to compile the ARM stuff since our target is ARM!

Time to enter a chroot! Once inside the chroot, all commends we execute will assume that /mnt/sd is our root filesystem. It’s a pretty cool trick. Note that we set LAN=C to suppress locale warnings in your chroot:

Let’s make some changes to the Pi’s filesystem. This is the cool part. All this is happening on your Pi’s filesystem!

Continue configuration as necessary. Once done, exit the chroot and unmount the SDcard.

We need to unmount all the directories we mounted:

Lastly, insert the SD card into the Pi, and launch!