From charlesreid1

This page covers how to connect a wifi hotspot created with hostapd with an OpenVPN connection with Kali Linux

This approach uses iptables to achieve the following configuration:

Hostapd diagram.png

Setup Hotspot

Set up the hotspot as described at Kali/Hotspot, but skip the section about connecting to an existing connection (which contains iptables commands). We'll run some different iptables commands to connect the wifi hotspot interface to the OpenVPN interface.

Just to summarize what Kali/Hotspot covers:

  • install necessary software (dhcpcd, dnsmasq, hostapd)
  • configure dhcpcd and dnsmasq
  • start dhcp and dnsmasq
  • configure hostapd
  • start hostapd

Setup OpenVPN

Set up the OpenVPN connection, which will create an interface like tun0 or tun1 (we will use tun1)

See Kali/OpenVPN for details about how to set up OpenVPN

See Kali/OpenVPN/PIA for details about how to set up OpenVPN with PIA VPN service

Setting iptables rules

Now that we have set up OpenVPN to run the vpn on interface tun1, we can set iptables rules to forward traffic between the hotspot and the OpenVPN interface.

We will modify the iptables rules from Kali/Hotspot to target the tun1 interface instead of the wlan2 interface.

# flush the tables
iptables -t nat -F
iptables -F

# add a postrouting rule to specify a mapping to an outgoing interface
iptables -t nat -A POSTROUTING -o tun1 -j MASQUERADE

# forward packets from wlan1 to tun1
iptables -A FORWARD -i wlan1 -o tun1 -j ACCEPT

# enable ipv4 forwarding
echo '1' > /proc/sys/net/ipv4/ip_forward