I'm using my pi3 to display a local "website" as described here Making a Raspberry Pi 3 accessible w/o configuration via WiFi and static IP/URL.
Therefore, I'm creating a hotspot with the pi. This hotspot has no connection to the internet. Thus, (correctly) all devices show the connection as broken, connect forever or drop the connection after a while. => SOLVED see Edit I Now I want to forward the devices which connect to this hotspot to my splash page.
I was wondering if I could configure the hotspot in a way that my local website is the login page.
Example,
this hotspot first connects and then opens up automatically a login page:
1 Connecting
2 Connected
3 Login Page
Question
How to configure the hotspot in a way that devices are automatically forwarded to http://localhost:80 on connecting.
Code
access point
#access point
apt-get install iw #Wireless tools
sudo apt-get install hostapd #Host Access Point Daemon
#config access point
cat /home/pi/myinstaller/wlan.config > /etc/hostapd/hostapd.conf
chmod 600 /etc/hostapd/hostapd.conf
#add to autostart
echo DAEMON_CONF=\"/etc/hostapd/hostapd.conf\" >> /etc/default/hostapd
#manual start with hostapd -dd /etc/hostapd/hostapd.conf
#router functions
Y | sudo apt-get install dnsmasq
cat /home/pi/myinstaller/dnmasq.config >> /etc/dnsmasq.conf
wlan.config
# WLAN-Router
# INTERFACE & DRIVERS
interface=wlan0
#driver=nl80211
# WLAN-CONFIG
ssid=someName #name of the wifi
channel=1
hw_mode=g
wmm_enabled=1
country_code=DE
ieee80211d=1
ignore_broadcast_ssid=0#1 is hidden, 0 visible
auth_algs=1
# WLAN-ENCRYPTION
wpa=2
wpa_key_mgmt=WPA-PSK
rsn_pairwise=CCMP
wpa_passphrase=somepassword
new dnsmasq.conf (EDIT I)
From: https://www.the-hawkes.de/dnsmasq-a-local-dnsdhcp-server-on-raspberry-pi.html
I restarted it after changing it with /etc/init.d/dnsmasq restart
######### dns ########
# Never forward plain names (without a dot or domain part)
domain-needed
# Never forward addresses in the non-routed address spaces
bogus-priv
# dont read resolv.conf use the defined servers instead
no-resolv
# increase dns cache form 512 to 4096
cache-size=4096
address=/#/127.0.1.1
######### dhcp ##########
# Add local-only domains here, queries in these domains are answered
# from /etc/hosts or DHCP only
local=/home/
# Set this (and domain: see below) if you want to have a domain
# automatically added to simple names in a hosts-file.
expand-hosts
# adds my localdomain to each dhcp host
domain=home
# my private dhcp range + subnetmask + 14d lease time
dhcp-range=192.168.178.10,192.168.178.99,255.255.255.0,14d
# set route to my local network router
dhcp-option=option:router,192.168.178.1
#windows 7 float fix
#http://brielle.sosdg.org/archives/522-Windows-7-flooding-DHCP-server-with-DHCPINFORM-messages.html
dhcp-option=252,"\n"
###### logging ############
# own logfile
log-facility=/var/log/dnsmasq.log
log-async
# log dhcp infos
log-dhcp
# debugging dns
#log-queries
ip-tables
These are applied with iptables-restore /etc/network/iptables. 127.0.1.1is the address of the localhost: raspberrypi.local which I found in /etc/hosts
*filter
:INPUT DROP [159:12505]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [140:13492]
-A INPUT -i lo -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A PREROUTING -p tcp --dport 80 -j DNAT --to 127.0.1.1:80
-A PREROUTING -p udp --dport 80 -j DNAT --to 127.0.1.1:80
-A INPUT -j REJECT --reject-with icmp-host-prohibited
COMMIT
*filter
:INPUT DROP [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [14020:1087947]
-A INPUT -i lo -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -i eth1 -j ACCEPT
COMMIT
*nat
:PREROUTING ACCEPT [71:10102]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [2:112]
:POSTROUTING ACCEPT [1:60]
:NET - [0:0]
-A PREROUTING -p tcp -m tcp --dport 80 -j DNAT --to-destination 127.0.1.1:80
-A PREROUTING -p udp -m udp --dport 80 -j DNAT --to-destination 127.0.1.1:80
-A POSTROUTING -o eth0 -j MASQUERADE
-A NET -j ACCEPT
COMMIT
iptables -t nat -A PREROUTING -p tcp --dport 80 -j DNAT --to-destination 127.0.0.1:80. tcp is enough for captive portal. If it doesn't work try to put other ip different to loopback ip. You must have another one, don't you?