LinuxQuestions.org - Quick and Easy wpa_supplicant / dhcpcd Script

Hey folks,

I'm relatively new to LFS but have had to rebuild it three times due to experimenting and fine-tuning. One of the first things I do after building the base is to get my wireless internet working. As neither LFS nor BLFS have a built-in bootscript for connecting my wlan0 interface with both 'dhcpcd' and 'wpa_supplicant', I thought I'd write my own. I've seen a couple other scripts posted on the BLFS wiki and in the hints, but they didn't seem simple enough. Anyways, this is my third time writing this script as I always forget to back it up prior to a reformat.

I am posting this to keep it off my computer so I can always get it again. If it helps anyone else out...all the better.

*** Ensure you have 'dhcpcd' and 'wpa_supplicant' installed and configured prior to continuing ***

First here is my 'ifconfig.wlan0' config file. I am using (at the time of writing) the development version SVN-20110918 so I have this file in the '/etc/sysconfig' directory. If you're running the stable version 6.8, place it in the '/etc/sysconfig/network-devices' directory instead:

Code:

# Begin /etc/sysconfig/ifconfig.wlan0



ONBOOT=yes

SERVICE=wpa-dhcpcd

IFACE=wlan0

DRIVER=wext

WPA_CONF="/etc/wpa_supplicant.conf"

DHCP_START=""

DHCP_STOP="-k"



# Set PRINTIP="yes" to have the script print

# the DHCP assigned IP address

PRINTIP="yes"



# Set PRINTALL="yes" to print the DHCP assigned values for

# IP, SM, DG, and 1st NS. This requires PRINTIP="yes".

PRINTALL="yes"



# End /etc/sysconfig/ifconfig.wlan0

And last, 'wpa-dhcpcd' goes in the '/lib/services' directory (if running on the development branch). If you're using 6.8, instead place this file in the '/etc/sysconfig/network-devices/services' directory:

Code:

#!/bin/sh

# Begin /lib/services/wpa-dhcpcd



# Based upon lfs-bootscripts-1.12 $network_devices/if{down,up}

# Rewritten by Nathan Coulson <nathan NOatSPAM linuxfromscratch NOdotSPAM org>

# Adapted for dhcpcd by DJ Lucas <dj NOatSPAM lucasit NOdotSPAM com>

# Adapted for wpa_supplicant by Brian Blumberg <blumbri NOatSPAM gmail NOdotSPAM com>



#$LastChangedBy: blumbri $

#$Date: 2011-09-18 11:16:21 +0000 (Sun, 18 Sep 2011) $



. /etc/sysconfig/rc

. $rc_functions

. $IFCONFIG



PIDFILE="/var/run/dhcpcd-$1.pid"

LEASEINFO="/var/lib/dhcpcd/dhcpcd-$1.info"

WPACTRL="/var/run/wpa_supplicant/$1"



case "$2" in

        up)

                boot_mesg -n "Starting wpa_supplicant on the $1 interface..."

                if [ -r "$WPACTRL" ]

                then

                        boot_mesg "wpa_supplicant already running!" ${WARNING}

                        echo_warning

                        exit 2

                fi

                /sbin/wpa_supplicant -i $IFACE -B -D $DRIVER -c "$WPA_CONF"

                # Save the return value

                RET="$?"

                echo ""

                $(exit "$RET")

                evaluate_retval



                boot_mesg -n "Starting dhcpcd on the $1 interface..."

                # Test to see if there is a stale pid file

                if [ -f "$PIDFILE" ]

                then

                        ps `cat "$PIDFILE"` | grep dhcpcd > /dev/null

                        if [ $? != 0 ]

                        then

                                rm -f $PIDFILE > /dev/null

                        else

                                boot_mesg "dhcpcd already running!" ${WARNING}

                                echo_warning

                                exit 2

                        fi

                fi

                /sbin/dhcpcd $1 $DHCP_START

                # Save the return value

                RET="$?"

                # Print the assigned settings if requested

                if [ "$RET" = "0" -a "$PRINTIP" = "yes" ]; then

                        . $LEASEINFO

                        if [ "$PRINTALL" = "yes" ]; then

                                echo ""

                                echo_ok

                                boot_mesg "          DHCP Assigned Settings for $1:"

                                boot_mesg_flush

                                boot_mesg "          IP Address:      $IPADDR"

                                boot_mesg_flush

                                boot_mesg "          Subnet Mask:    $NETMASK"

                                boot_mesg_flush

                                boot_mesg "          Default Gateway: $GATEWAYS"

                                boot_mesg_flush

                                boot_mesg "          DNS Server:      $DNSSERVERS"

                                boot_mesg_flush

                        else

                                boot_mesg " IP Addresss: $IPADDR"

                                echo_ok

                        fi

                else

                        echo ""

                        $(exit "$RET")

                        evaluate_retval

                fi

        ;;



        down)

                boot_mesg -n "Stopping dhcpcd on the $1 interface..."

                if [ -z "$DHCP_STOP" ]

                then

                        echo ""

                        killproc -p "$PIDFILE" /sbin/dhcpcd

                else

                        /sbin/dhcpcd $1 $DHCP_STOP &> /dev/null

                        RET="$?"

                        if [ "$RET" -eq 0 ]; then

                                echo ""

                                echo_ok

                        elif [ "$RET" -eq 1 ]; then

                                boot_mesg "dhcpcd not running!" ${WARNING}

                                echo_warning

                        else

                                echo ""

                                echo_failure

                        fi

                fi



                boot_mesg -n "Stopping wpa_supplicant on the $1 interface..."

                WPAPID=$(echo $(ps x | grep /sbin/wpa_supplicant | grep $IFACE) | cut -d' ' -f1)

                if [ "x$WPAPID" != "x" ]

                then

                        kill $WPAPID &> /dev/null

                        RET="$?"

                        if [ "$RET" -eq 0 ]; then

                                echo ""

                                echo_ok

                        else

                                echo ""

                                echo_failure

                        fi

                else

                        boot_mesg "wpa_supplicant not running!" ${WARNING}

                        echo_warning

                fi

        ;;



        *)

                echo "Usage: $0 [interface] {up|down}"

                exit 1

        ;;

esac



# End /lib/services/wpa-dhcpcd

After doing this, upon boot (or running '/etc/rc.d/init.d/network start') your interface should be brought up, wpa_supplicant started, and dhcpcd loaded. Hopefully this helps someone!

Please let me know if you have any questions/comments.

-- blumbri