Quick Start
In this article, we assume you are familiar with original udp2raw, if you are not, check https://github.com/wangyu-/udp2raw-tunnel and come back later.
Assume you have a servce listening at udp port 7777 of your linux server , but a firewall restricts the udp connection in the middle. Now you want to use udp2raw to bypass the restriction. The system of your local computer is Windows/Mac.
Download and run udp2raw server on VPS, from this address：https://github.com/wangyu-/udp2raw-tunnel/releases
Use following commands：
# Run at server side:
./udp2raw_amd64 -s -l0.0.0.0:4096 -r 127.0.0.1:7777 -a -k "passwd" --raw-mode faketcp(if you want to keep udp2raw running after ssh exited，google for the usage of either of nohup/screen/tmux)
Install pcap, for details check this link。
Download udp2raw clients，from this link .(For some platforms, there might be two files in the tar ball, use the one with _nolibnet suffix. For easier typing, you can remove the suffix of _nolibnet manullay. In the following article, we will assume you have already removed the _nolibnet suffix).
# Run at client side
udp2raw_mp.exe -c -l0.0.0.0:3333 -r44.55.66.77:4096 -k "passwd" --raw-mode easy-faketcp
easy-faketcp is a new mode of udp2raw_mp，its able to commuicate with a server of faketcp，without the need of adding iptables/firewalls rules .
(There is color on my side, because I am using msys2 shell and added the option of --enable-color. If you are using cmd/powershell in windows, there is no color.)
Everthing is done. Now, connecting to 127.0.0.1:3333 (udp) is equivalent to connecting to udp port 7777 on VPS, every udp packet will be "faked" into tcp, no udp traffic will be exposed.
easy-faketcp mode is easy but not optimal. With a few addition steps, you can use the faketcp mode for better performance/stability, its suggested to use faketcp mode.
First , use -g options to generate the needed firwall rules.
udp2raw_mp.exe -c -l0.0.0.0:3333 -r44.55.66.77:4096 -k "passwd" --raw-mode faketcp -g
Expected Outputs：
For example , on windows，use：
netsh advfirewall firewall add rule name=udp2raw protocol=TCP dir=in remoteip=44.55.66.77/32 remoteport=4096 action=block
netsh advfirewall firewall add rule name=udp2raw protocol=TCP dir=out remoteip=44.55.66.77/32 remoteport=4096 action=block
Just copy and paste and run。
Delete -g optional ，run udp2raw again：
udp2raw_mp.exe -c -l0.0.0.0:3333 -r44.55.66.77:4096 -k "passwd" --raw-mode faketcp
Done, now you can use the more performanced faketcp mode. In this way, you can also use icmp mode(which turns udp traffic into icmp of course).