Initramfs

/etc/portage/package.keywords

sys-fs/cryptsetup ~amd64
sys-fs/lvm2 ~amd64
sys-fs/udev ~amd64

/etc/portage/package.use

net-misc/openssh static
sys-apps/busybox static
sys-fs/mdadm static

/usr/src/initramfs/init

#!/bin/busybox sh

SSH_IP=192.168.42.253
SSH_PORT=4224
SSH_IFACE=eth0
ROOT_DEVICE=/dev/mapper/md2
ROOT_PASSWD="password"
ALLOW_SH=1

###################################################################
## func
###################################################################

rshell() {
    echo "## bringing network on $SSH_IFACE:$SSH_IP"
    ifconfig $SSH_IFACE $SSH_IP up
        /bin/sshd -p $SSH_PORT
}

mydev() {
    [ -c /dev/console ] || mknod -m 600 /dev/console c 5 1
    [ -c /dev/tty1 ] || mknod -m 620 /dev/tty1 c 4 1
    [ -c /dev/tty ] || mknod -m 666 /dev/tty c 5 0
    [ -c /dev/null ] || mknod -m 666 /dev/null c 1 3
    [ -c /dev/kmsg ] || mknod -m 660 /dev/kmsg c 1 11
    ln -snf /proc/self/fd /dev/fd
    ln -snf fd/0 /dev/stdin
    ln -snf fd/1 /dev/stdout
    ln -snf fd/2 /dev/stderr
    [ -e /proc/kcore ] && ln -snf /proc/kcore /dev/core
    mkdir -p /dev/pts /dev/shm
    udevd --daemon
    udevadm control --env do_not_run_plug_service=1
    udevadm trigger --attr-match=dev
    udevadm trigger --subsystem-match=net
    udevadm settle  --timeout=60
    udevadm control --env do_not_run_plug_service=
    mount -n -t devpts devpts /dev/pts
    MAKEDEV -d ptmx
}

sysinit() {
    echo "#############################################################"
    echo "##Awired initramfs"
    echo "#############################################################"

    echo "## Loading keyboard map"
    loadkmap < keymap.bin

    echo "## Install busybox"
    busybox --install -s

    echo "## Mount the /proc and /sys filesystems"
    mount -n -t proc proc /proc
    mount -n -t sysfs sysfs /sys

    echo "## Populating /dev with udev"
    mydev

    echo "## change root password"
    echo "root:$ROOT_PASSWD" | chpasswd

    echo "## Running remote shell with sshd"
    rshell

    echo "## run screen"
    screen ./init "lets go"

    while [ `cat /proc/mounts | grep /new | wc -l` == 0 ]
    do
        screen ./init "Trying to switch_root but /new is not mounted !!!!!!" "1"
    done

        echo "## Clean up"
        killall sshd
        killall udevd
        umount /dev/pts
        umount /proc
        umount /sys

    echo "## switch root to /new"
    exec switch_root /new /sbin/init
}

tshell() {
    if [ $ALLOW_SH == "1" ]; then
        echo "## drop you to a shell : $1"
        /bin/sh --noprofile
    fi
}

ucryptdd() {
    cd /dev/
    # uncrypt raid drives
    for i in $( ls -1 md? ); do
            if [[ "$i" == "md0" || "$i" == "md1" ]] ; then
                    echo "## skipping $i";
            else
                    echo "## trying to uncrypt : $i";
                    cryptsetup luksOpen /dev/$i $i;
            fi
    done

    # uncrypt non raid drives
    for i in $( ls -1 sd?? ); do
            if grep -q "$i" "/proc/mdstat"; then
                    echo "## skip $i as its in use by a raid array";
            else
                    echo "## trying to uncrypt : $i";
                    cryptsetup luksOpen /dev/$i $i;
            fi
    done
}

###########################################################################

if [ -z "$1" ]; then
    sysinit
else

   if [ -z "$2" ]; then

        echo "## Loading raid devices"
        mdadm --auto-detect || tshell

        echo "## uncrypt drives"
        ucryptdd

        echo "## mount swap"
        cryptsetup -d /dev/urandom create swap /dev/md2
        mkswap /dev/mapper/swap
        swapon /dev/mapper/swap

        echo "## Mount $ROOT_DEVICE"
        mount -n $ROOT_DEVICE /new
    else
        tshell "$1"
    fi

    exit
fi

/usr/src/initramfs/gen.sh

mount /boot
find . -print0 | cpio -ov -0 --format=newc | gzip -9 > /boot/initramfs.gz

/etc/portage/package.use

#net-misc/openssh static
sys-apps/busybox static
sys-fs/mdadm static