#!/bin/sh
# Script to start/stop a hostapd-based access point
#
# Sample start call "control_ap start wlan0 eth0"
# Stop with "control_ap stop"
#

case "$1" in
start)
	if [ $# -ne 3 ]
	then
	  echo "Usage: $0 start AP_iface NET_iface"
	  exit 1
	fi
;;
stop)
	if [ $# -ne 1 ]
	then
	  echo "Usage: $0 stop"
	  exit 1
	fi
;;
*)
        echo "Usage:"
	echo "$0 start AP-iface net_iface"
	echo "or"
	echo "$0 stop"
        exit 1
        ;;
esac

# Symbols for needed programs

IPTABLES=/sbin/iptables
IFCONFIG=/usr/bin/ifconfig
DHCPD=/sbin/dhcpd
HOSTAPD=$(pwd)/hostapd-2.9/hostapd/hostapd

# Symbols for AP and external interfaces

NET_AP=$2
NET_EXT=$3

# First 3 octets of IP address for the AP

AP_ADDR=192.168.0

# IP address for nameserver

NAME_SERVER=8.8.8.8

# AP Channel, SSID, Encryption method, driver,  and Encryption secret

AP_CHANNEL=11
AP_SSID=rtwap
WPA_SECRET="87654321"
ENCRYPT_MODE=2
DRIVER=rtl871xdrv

case "$1" in
start)
        echo "Starting AP mode for $NET_AP at address $AP_ADDR.1"
        # Disable packet forwarding
        echo 0 > /proc/sys/net/ipv4/ip_forward
        # Stop any existing hostapd and dhcpd daemons
        killall -q hostapd
        killall -q dhcpd
        #Set up forwarding
        $IPTABLES -t nat -A POSTROUTING -o $NET_EXT -j MASQUERADE
        $IPTABLES -A FORWARD -i $NET_EXT -o $NET_AP -m state \
		--state RELATED,ESTABLISHED -j ACCEPT
        $IPTABLES -A FORWARD -i $NET_AP -o $NET_EXT -j ACCEPT
        # Get the AP interface in the right state
        $IFCONFIG $NET_AP down
        $IFCONFIG $NET_AP up
        $IFCONFIG $NET_AP $AP_ADDR.1
        # dhcpd needs to have a leases file available - create it if needed
        if [ ! -f /var/lib/dhcp/db/dhcpd.leases ]; then
		mkdir -p /var/lib/dhcp/db
                touch /var/lib/dhcp/db/dhcpd.leases
        fi
	# Write the DHCP server configuration file
	echo "option domain-name-servers $NAME_SERVER;" > dhcpd.conf
	echo "default-lease-time 600;" >> dhcpd.conf
	echo "ddns-update-style none; ddns-updates off;" >> dhcpd.conf
	echo "subnet $AP_ADDR.0 netmask 255.255.255.0 {" >> dhcpd.conf
	echo "        max-lease-time 7200;" >> dhcpd.conf
	echo "        range $AP_ADDR.200 $AP_ADDR.229;" >> dhcpd.conf
	echo "        option subnet-mask 255.255.255.0;" >> dhcpd.conf
	echo "        option broadcast-address $AP_ADDR.255;" >> dhcpd.conf
	echo "        option routers $AP_ADDR.1;" >> dhcpd.conf
	echo "}" >> dhcpd.conf
        # Bring up the DHCP server
        $DHCPD -cf dhcpd.conf $NET_AP
	# Write the hostapd configuration file
	cat > hostapd << EOF
auth_algs=1
beacon_int=100
country_code=US
ctrl_interface_group=0
ctrl_interface=/var/run/hostapd
dtim_period=2
fragm_threshold=2346
#ht_capab=[HT40-][SHORT-GI-20][SHORT-GI-40][MAX-AMSDU-7935][DSSS_CCK-40]
#ieee80211d=1
#ieee80211n=1
ignore_broadcast_ssid=0
logger_stdout=-1
logger_stdout_level=2
logger_syslog=-1
logger_syslog_level=2
macaddr_acl=0
max_num_sta=255
rts_threshold=2347
wmm_ac_be_acm=0
wmm_ac_be_aifs=3
wmm_ac_be_cwmax=10
wmm_ac_be_cwmin=4
wmm_ac_be_txop_limit=0
wmm_ac_bk_acm=0
wmm_ac_bk_aifs=7
wmm_ac_bk_cwmax=10
wmm_ac_bk_cwmin=4
wmm_ac_bk_txop_limit=0
wmm_ac_vi_acm=0
wmm_ac_vi_aifs=2
wmm_ac_vi_cwmax=4
wmm_ac_vi_cwmin=3
wmm_ac_vi_txop_limit=94
wmm_ac_vo_acm=0
wmm_ac_vo_aifs=2
wmm_ac_vo_cwmax=3
wmm_ac_vo_cwmin=2
wmm_ac_vo_txop_limit=47
wmm_enabled=1
EOF
	echo "interface=$NET_AP" >> hostapd
	echo "ssid=$AP_SSID" >> hostapd
	echo "driver=$DRIVER" >> hostapd
	echo "hw_mode=g" >> hostapd
	echo "channel=$AP_CHANNEL" >> hostapd
	echo "wpa=$ENCRYPT_MODE" >> hostapd
	echo "wpa_key_mgmt=WPA-PSK" >> hostapd
	echo "wpa_pairwise=TKIP CCMP" >> hostapd
	echo "rsn_pairwise=CCMP" >> hostapd
	echo "wpa_passphrase=$WPA_SECRET" >> hostapd
        # Enable packet forwarding
        echo 1 > /proc/sys/net/ipv4/ip_forward
        # Bring up hostapd
        $HOSTAPD -dd -B hostapd
        ;;
stop)
        echo "Stopping AP mode"
        # Stop hostapd and dhcpd daemons
        killall hostapd
        killall dhcpd
	rm -f hostapd
	rm -f dhcpd.conf
        ;;
esac