# Linux-router
Set Linux as router in one command. Able to Provide Internet, or create Wifi hotspot. Support transparent proxy (redsocks). Also useful for routing VM/containers.
It wraps `iptables`, `dnsmasq` etc. stuff. Use in one command, restore in one command or by `control-c`.
[Buy me a coffee](https://github.com/garywill/receiving/blob/master/receiving_methods.md)
## Features
Basic features:
- Create a NATed sub-network
- Provide Internet
- DHCP server and RA
- DNS server
- IPv6 (NAT only for now)
- Creating Wifi hotspot:
- Channel selecting
- Choose encryptions: WPA2/WPA, WPA2, WPA, No encryption
- Hidden SSID
- Create AP on the same interface you are getting Internet (require same channel)
- Transparent proxy (redsocks)
- DNS proxy
- Compatible with NetworkManager (automatically set interface as unmanaged)
**For many other features, see below [CLI usage](#cli-usage-and-other-features)**
### Useful in these situations
```
Internet----(eth0/wlan0)-Linux-(wlanX)AP
|--client
|--client
```
```
Internet
Wifi AP(no DHCP) |
|----(wlan1)-Linux-(eth0/wlan0)------
| (DHCP)
|--client
|--client
```
```
Internet
Switch |
|---(eth1)-Linux-(eth0/wlan0)--------
|--client
|--client
```
```
Internet----(eth0/wlan0)-Linux-(eth1)------Another PC
```
```
Internet----(eth0/wlan0)-Linux-(virtual interface)-----VM/container
```
## Usage
### Provide Internet to an interface
```
# lnxrouter -i eth1
```
### Provide an interface's Internet to another interface
```
# lnxrouter -i eth1 -o vpn0 --dhcp-dns 1.1.1.1
```
### Create Wifi hotspot
```
# lnxrouter --ap wlan0 MyAccessPoint --password MyPassPhrase
```
### LAN without Internet
```
# lnxrouter -n -i eth1
# lnxrouter -n --ap wlan0 MyAccessPoint --password MyPassPhrase
```
### Transparent proxy with Tor
```
# lnxrouter -i eth1 --tp 9040 --dns 9053
```
In `torrc`
```
TransPort 0.0.0.0:9040
DNSPort 0.0.0.0:9053
TransPort [::]:9040
DNSPort [::]:9053
```
### Internet for LXC
Create a bridge
```
# brctl addbr lxcbr5
```
In LXC container `config`
```
lxc.network.type = veth
lxc.network.flags = up
lxc.network.link = lxcbr5
lxc.network.hwaddr = xx:xx:xx:xx:xx:xx
```
```
# lnxrouter -i lxcbr5
```
### Use as transparent proxy for LXD
Create a bridge
```
# brctl addbr lxdbr5
```
Create and add LXD profile
```
$ lxc profile create profile5
$ lxc profile edit profile5
### profile content ###
config: {}
description: ""
devices:
eth0:
name: eth0
nictype: bridged
parent: lxdbr5
type: nic
name: profile5
$ lxc profile add <container> profile5
```
That should make one container have 2 profiles. `profile5` will override `eth0`.
```
# lnxrouter -i lxdbr5 --tp 9040 --dns 9053
```
To remove that new profile from container
```
$ lxc profile remove <container> profile5
```
#### To not use profile
Add device `eth0` to container overriding default `eth0`
```
$ lxc config device add <container> eth0 nic name=eth0 nictype=bridged parent=lxdbr5
```
To remove the customized `eth0` to restore default `eth0`
```
$ lxc config device remove <container> eth0
```
### Use as transparent proxy for VirtualBox
On VirtualBox's global settings, create a host-only network `vboxnet5` with DHCP disabled.
```
# lnxrouter -i vboxnet5 --tp 9040 --dns 9053
```
### Use as transparent proxy for firejail
Create a bridge
```
# brctl addbr firejail5
```
```
# lnxrouter -i firejail5 -g 192.168.55.1 --tp 9040 --dns 9053
$ firejail --net=firejail5 --dns=192.168.55.1
```
### CLI usage and other features
```
Usage: lnxrouter <options>
Options:
-h, --help Show this help
--version Print version number
-i <interface> Interface to make NATed sub-network,
and to provide Internet to
(To create Wifi hotspot use '--ap' instead)
-o <interface> Specify an inteface to provide Internet from.
(Note using this with default DNS option may leak
queries to other interfaces)
-n Do not provide Internet
-g <ip> Set this host's IPv4 address, netmask is 24
-6 Enable IPv6 (NAT)
--p6 <prefix> Set IPv6 prefix (length 64) (example: fd00:1:2:3::)
--dns <ip>|<port>|<ip:port>
DNS server's upstream DNS.
Use ',' to seperate multiple servers
(default: use /etc/resolve.conf)
(Note IPv6 addresses need '[]' around)
--no-dns Do not serve DNS
--no-dnsmasq Disable dnsmasq server (DHCP, DNS, RA)
--catch-dns Transparent DNS proxy, redirect packets(TCP/UDP)
that destination port is 53 to this host
--log-dns Show DNS query log
--dhcp-dns <IP1[,IP2]>|no
Set IPv4 DNS offered by DHCP (default: this host)
--dhcp-dns6 <IP1[,IP2]>|no
Set IPv6 DNS offered by DHCP (RA)
(default: this host)
(Note IPv6 addresses need '[]' around)
--hostname <name> DNS server associate this name with this host.
Use '-' to read name from /etc/hostname
-d DNS server will take into account /etc/hosts
-e <hosts_file> DNS server will take into account additional
hosts file
--mac <MAC> Set MAC address
--tp <port> Transparent proxy,
redirect non-LAN TCP and UDP traffic to port.
Usually used with '--dns'
Wifi hotspot options:
--ap <wifi interface> <SSID>
Create Wifi access point
--password <password> Wifi password
--hidden Hide access point (not broadcast SSID)
--no-virt Do not create virtual interface
Using this you can't use same wlan interface
for both Internet and AP
-c <channel> Channel number (default: 1)
--country <code> Set two-letter country code for regularity
(example: US)
--freq-band <GHz> Set frequency band: 2.4 or 5 (default: 2.4)
--driver Choose your WiFi adapter driver (default: nl80211)
-w <WPA version> Use 1 for WPA, use 2 for WPA2, use 1+2 for both
(default: 1+2)
--psk Use 64 hex digits pre-shared-key instead of
passphrase
--mac-filter Enable Wifi hotspot MAC address filtering
--mac-filter-accept Location of Wifi hotspot MAC address filter list
(defaults to /etc/hostapd/hostapd.accept)
--hostapd-debug <level> 1 or 2. Passes -d or -dd to hostapd
--isolate-clients Disable wifi communication between clients
--ieee80211n Enable IEEE 802.11n (HT)
--ieee80211ac Enable IEEE 802.11ac (VHT)
--ht_capab <HT> HT capabilities (default: [HT40+])
--vht_capab <VHT> VHT capabilities
--no-haveged Do not run haveged automatically when needed
Instance managing:
--daemon Run in background
--list-running Show running instances
--list-clients <id> List clients of an instance
--stop <id> Stop a running instance
For <id> you can use PID or subnet interface name.
You can get them with '--list-running'
```
> These changes to system will not be restored by script's cleanup:
> 1. `/proc/sys/net/ipv4/ip_forward = 1` and `/proc/sys/net/ipv6/conf/all/forwarding = 1`, needed by NAT Internet sharing.
> 2. dnsmasq in Apparmor complain mode
## Dependencies
- bash
- procps or procps-ng
- iproute2
- dnsmasq
- iptables
Wifi hotspot:
- hostapd
- iw
- iwconfig (you only need this if 'iw' can not recognize your adapter)
- haveged (optional)
## TODO
- Option to ban private network access
- Option to randomize MAC
## Donate
[Buy me a coffee](https://github.com/garywill/receiving/blob/master/receiving_methods.md)
## Thanks
Many thanks to project [create_ap](https://github.com/oblique/create_ap).