Mini Shell

#!/usr/bin/sh

PATH=/usr/sbin:/usr/bin:/sbin:/bin
command -v getarg > /dev/null || . /lib/dracut-lib.sh
command -v setup_net > /dev/null || . /lib/net-lib.sh

# Huh? Empty $1?
[ -z "$1" ] && exit 1

# [ ! -z $2 ] means this is for manually bringing up network
# instead of real netroot; If It's called without $2, then there's
# no sense in doing something if no (net)root info is available
# or root is already there
[ -d "$NEWROOT"/proc ] && exit 0

if [ -z "$netroot" ]; then
    netroot=$(getarg netroot=)
fi

[ -z "$netroot" ] && exit 1

# Set or override primary interface
netif=$1
[ -e "/tmp/net.bootdev" ] && read -r netif < /tmp/net.bootdev

case "$netif" in
    ??:??:??:??:??:??) # MAC address
        for i in /sys/class/net/*/address; do
            mac=$(cat "$i")
            if [ "$mac" = "$netif" ]; then
                i=${i%/address}
                netif=${i##*/}
                break
            fi
        done ;;
esac

# Figure out the handler for root=dhcp by recalling all netroot cmdline
# handlers when this is not called from manually network bringing up.
if [ -z "$2" ]; then
    if getarg "root=dhcp" || getarg "netroot=dhcp" || getarg "root=dhcp6" || getarg "netroot=dhcp6"; then
        # Load dhcp options
        # shellcheck disable=SC1090
        [ -e /tmp/dhclient."$netif".dhcpopts ] && . /tmp/dhclient."$netif".dhcpopts

        # If we have a specific bootdev with no dhcpoptions or empty root-path,
        # we die. Otherwise we just warn
        if [ -z "$new_root_path" ]; then
            [ -n "$BOOTDEV" ] && die "No dhcp root-path received for '$BOOTDEV'"
            warn "No dhcp root-path received for '$netif' trying other interfaces if available"
            exit 1
        fi

        rm -f -- "$hookdir"/initqueue/finished/dhcp.sh

        # Set netroot to new_root_path, so cmdline parsers don't call
        netroot=$new_root_path

        # FIXME!
        unset rootok
        for f in "$hookdir"/cmdline/90*.sh; do
            # shellcheck disable=SC1090
            [ -f "$f" ] && . "$f"
        done
    else
        rootok="1"
    fi

    # Check: do we really know how to handle (net)root?
    if [ -z "$root" ]; then
        root=$(getarg root=)
    fi
    [ -z "$root" ] && die "No or empty root= argument"
    [ -z "$rootok" ] && die "Don't know how to handle 'root=$root'"

    handler=${netroot%%:*}
    handler=${handler%%4}
    handler=$(command -v "${handler}"root)
    if [ -z "$netroot" ] || [ ! -e "$handler" ]; then
        die "No handler for netroot type '$netroot'"
    fi
fi

# Source netroot hooks before we start the handler
source_hook netroot "$netif"

# Run the handler; don't store the root, it may change from device to device
# XXX other variables to export?
[ -n "$handler" ] && "$handler" "$netif" "$netroot" "$NEWROOT"
save_netinfo "$netif"

exit 0