wifi.sh

#!/bin/bash

# wifi: Linux absolutely sucks at network management. Want two devices up,
#       forget it. Would use networkmanager from cli but gnome sucks so
#       hard at integrating. 
#       We'd use wicd, which is much more stable, but it cannot support
#       multiple interfaces at once. 
#
#   it is 2115 and linux still can't dynamicly select with multi interfaces.
#
#   wifi         list ssid's
#   wifi auto    connect to known networks
#   wifi <ssid>  connect to SSID. Use passwd in db else request passwd
#   wifi <ssid> <passwd>
#
# Note: passwords are stored in a plaintext file


# sudo call integrity check: only root should be able to change script
l=($(ls -l `readlink -f $0`))
[ ${l[0]:2:1} != "-" ] && [ "${l[2]}" != "root" ] ||
[ ${l[0]:5:1} != "-" ] && [ "${l[3]}" != "root" ] ||
[ ${l[0]:8:1} != "-" ] && { echo -e "only root should be able to modify\n${l[@]}"; exit 1;}

#ETH="wlp3s0" #AKA Love SystemD or die!
#ETH="wlan0"
ETH=`ls /sys/class/net/|grep wl|head -1`


# Wifi password db
WIFIPASSWDFILE="$HOME/.wifidb"
if [ -f "$WIFIPASSWDFILE" ]; then
    source "$WIFIPASSWDFILE"
else
    declare -A WIFIPASSWD
fi
if [ $# -eq 0 ] || [ "$1" == "list" ]; then
    sudo ifconfig $ETH up
    scan=$(sudo iwlist $ETH scanning)
    while [ $? -ne 0 ]; do  
        sleep 1
        scan=$(sudo iwlist $ETH scanning)
    done
    echo "$scan" | egrep 'ESSID|Quality|Encryption key:' | xargs | sed 's/Quality=/\n/g' | sed 's/ESSID:\| *Signal level\|Encryption key://g' | sed 's/ on / on  /g' | sort --field-separator="=" -k 1
else
    if [ "$1" = "auto" ]; then
        echo "# Attempting to connect to known networks"
        sudo ifconfig $ETH up || exit
        oIFS=$IFS
        IFS=$'\n'
        scan=$(sudo iwlist $ETH scanning)
        ssids=$(echo "$scan" | egrep 'ESSID' | sed 's/ *ESSID:"\|"//g')
        list=$(echo "$scan" | egrep 'ESSID|Quality|Encryption key:' | xargs | sed 's/Quality=/\n/g' | sed 's/ESSID:\| *Signal level\|Encryption key://g' | sed 's/ on / on  /g' | sort --field-separator="=" -k 1)
        # in casese where there are 2+ known networks connect to most recent:
        #for ssid in $ssids; do
        #    if [ "${WIFIPASSWD[$ssid]+ISSET}" == "ISSET" ]; then
        #        echo "Will connect to $ssid"
        #        set -- $ssid
        #               break
        #    fi
        #done
        # sadly this order by top entry doesnt work. Reading in hash reorders list
        for knownssid in "${!WIFIPASSWD[@]}"; do
                if [ "$(echo "$ssids" | grep "^$knownssid$")x" != "x" ]; then
                        echo "# Will connect to $knownssid"
                        set -- $knownssid
                        break
                fi
        done
        IFS=$oIFS
        if [ "$1" == "auto" ]; then
                echo "# no known ssid found"
                echo "$list"
                exit
        fi
        elif [ "$1" = "status" ]; then
        iwconfig $ETH
        exit
     fi

        echo "# Connecting to SSID \"$1\""
        sudo killall wpa_supplicant
        /bin/ps -C dhclient -f h | grep $ETH | awk '{print $2}' | xargs sudo kill 2>/dev/null

        if [ $# -eq 2 ]; then
            echo "# Setting password"
            PASSWORD="$2"
        elif [ "${WIFIPASSWD[$1]+ISSET}" == "ISSET" ]; then
            echo "# Have password"
            PASSWORD="${WIFIPASSWD["$1"]}"
        else
            read -s -p "Password for $1 (or none): " PASSWORD
        fi
        WIFIPASSWD["$1"]="$PASSWORD"
        tmp=$(declare -p WIFIPASSWD | sed -e 's/\[/\n\[/g' )
        echo "$tmp" > "${WIFIPASSWDFILE}"
        sudo chmod 770 "$WIFIPASSWDFILE"

        if [ "$PASSWORD" == "" ]; then
            echo -e "\n# Connecting without password"
            sudo iwconfig $ETH essid "$1" key open || exit
            if [ $? -ne 0 ]; then
                echo "!! Error: couldn't connect"
                exit
            fi
        else
            echo "# Connecting with password "
        tmpfile=$(mktemp)
        #echo "# iwconfig with key"
        #sudo nmcli dev wifi connect "$1" password "$PASSWORD"
        #sudo iwconfig wlp3s0 essid "$1" key s:$PASSWORD
        #sudo iwconfig wlp3s0 essid "$1" key "s:$PASSWORD" \
        wpa_passphrase "$1" "$PASSWORD" > $tmpfile  || exit
        wpafile=/tmp/wpa_supplicant.${ETH}.log
        rm $wpafile 2>/dev/null
        sudo wpa_supplicant -B -i $ETH -c $tmpfile -d -f $wpafile
        #  tail -f /tmp/wpa_supplicant.wlp3s0.log | egrep 'reason|SUCCESS|result'
        while [ 1 ]; do
                grep -q 'reason=WRONG_KEY' $wpafile && echo -e "\n# Bad password?" && exit
                grep -q 'INTERFACE_DISABLED' $wpafile && echo -e "# Interface disabled" && exit
                grep -q 'result=SUCCESS' $wpafile && echo -e "\n# Good password" && break
                sleep 0.5
                echo -n "."
        done
        if [ $? -ne 0 ]; then
            echo "!! Error: couldn't connect with password"
            exit
        fi
    fi
    sudo rm /tmp/dhclient.${ETH}.leases 2>/dev/null
        # clear default gw first
        # ip route del 0/0
        sudo route del default 2>/dev/null # error on no default exist
        echo "initial-interval 1;" > /tmp/dhclient.conf
        echo "backoff-cutoff 1;" >> /tmp/dhclient.conf
        sudo dhclient -1 -v -cf /tmp/dhclient.conf -pf /run/dhclient.${ETH}.pid -lf /tmp/dhclient.${ETH}.leases $ETH 2>&1 | egrep 'DHCP|bound'

        # all failed:
        #echo "" > /tmp/dhclient.conf
        ##echo "send dhcp-requested-address 192.168.100.111, ;" >> /tmp/dhclient.conf
        #echo "request;" >> /tmp/dhclient.conf
        #echo "send option dhcp-client-identifier \"foo\";" >> /tmp/dhclient.conf
        #echo "send option host-name \"foo\";" >> /tmp/dhclient.conf
        #sudo dhclient -v -cf /tmp/dhclient.conf -pf /run/dhclient.${ETH}.pid -lf /tmp/dhclient.${ETH}.leases $ETH 
fi

#elif [ "${!WIFIPASSWD[@]+$1}" ]; then
#elif echo "${!WIFIPASSWD[@]}" | grep -q "$1"; then

# Non NM but with root for bash -c
#sudo iwconfig wlp3s0 essid "$1" key "s:$PASSWORD" \
#  || bash -c "wpa_supplicant -B -i wlp3s0 -c <(wpa_passphrase \"$1\" \"$PASSWORD\")"
# Without bash -c
# if key is hex remove "s:" prefix:
# iwconfig wlp3s0 essid key <wireless key>