A secured UDP tunnel written in Rust.
rstun builds on Quinn, which is an implementation of the IETF QUIC transport protocol.
rstun consists of two binaries, rstunc
for client and rstund
for server. rstund
accepts connections from rstunc
.
rstunc
connects to the server to build a secured tunnel to allow data to be exchanged between two ends, it initiates the connection in one of two modes:
- The
IN
mode for exposing a local port to the internet through the server. - The
OUT
mode for securing data going out from local to the internet through the server.
All traffic going through the tunnel is secured by the builtin TLS layer of the QUIC protocol, when the negotiation of the connection completes and a tunnel is built, QUIC streams can be initiated from both ends, for the OUT
mode, streams are initiated from the client, and for the IN
mode, it is just the opposite.
- Start the server
rstund \
--addr 0.0.0.0:6060 \
--upstreams 8800 \
--password 123456 \
--cert path/to/cert.der \
--key path/to/key.der
addr
specifies the ip:port that the server is listening on.upstreams
specifies a TCP port which traffic from the client through the tunnel will be relayed to on the server, this is applicable forOUT
mode tunnels only, multiple space-separated upstreams can be set. Note this argument is optional, if it is not specified, all open ports of the server are exposed to the clients through the tunnel. So make sure to specify upstreams if exposing all open ports of the server is not desired.password
, password of the server, the clientrstunc
is required to send this password to successfully build a tunnel with the server.cert
andkey
are certificate and private key for the domain of the server and they must be inDER
format (binary format), self-signed certificate is allowed, but you will have to connect to the server using IP address and the certificate will also be required byrstunc
for verification in this case (see below). Anyway, getting a certificate for your domain from a trusted CA and connecting to the server using domain name is always recommended. Notecert
andkey
are optional, if they are not specified, the domainlocalhost
is assumed and a self-signed certificate is generated on the fly, but this is for TEST only, Man-In-The-Middle attack can occur with such setting, so make sure it is only used for TEST!
- Start the client
rstunc
--mode OUT \
--server-addr 1.2.3.4:6060 \
--password 123456 \
--cert path/to/cert.der \
--addr-mapping 0.0.0.0:9900^8800
mode
here isOUT
forTunnelOut
, for securing traffic from local to the server through the tunnel.server-addr
, domain name or IP address of the server.password
, same as that for the server.cert
, see explanation above forrstund
. Note this is also optional if connecting to the server with a domain name, or the serverrstund
runs with an auto-generated self-signed certificate (see the TEST example below).addr-mapping
is an address mapping between twoip:port
pairs separated by the^
character, the format is[ip:]port^[ip:]port
, in the example above, a local port9900
is mapped to the remote port8800
of the1.2.3.4
server that runsrstund
. i.e. all traffic from the local port9900
will be forwarded to the remote port8800
through the tunnel.addr-mapping
also supports the following 3 combinations:ANY^8000
for not explicitly specifying a port for the local access server (the client), the bound port will be printed to the terminal as following[TunnelOut] access server bound to: 0.0.0.0:60001
, in which60001
is a random port.8000^ANY
for not explicitly specifying a port to bind with the remote server, the server decides that port, so it depends on that the server is started with explicitly setting the--upstreams
option.ANY^ANY
both the cases of the settings above.
- Simple TEST example
The following commands run a server and a client that connects to the server in their simplest ways:
# Remote: run the server with auto-generated self-signed certificate
rstund -a 9000 -p 1234
# Local: connect to the server (127.0.0.1:9000) and bind the local port 9900 to remote port 8800
rstunc -m OUT -r 127.0.0.1:9000 -p 1234 -a 0.0.0.0:9900^8800
- Complete options for
rstund
USAGE:
rstund [OPTIONS] --password <PASSWORD>
OPTIONS:
-a, --addr <ADDR>
Address ([ip:]port pair) to listen on, a random port will be chosen and binding to all
network interfaces (0.0.0.0) if empty [default: ]
-u, --upstreams <UPSTREAMS>
Exposed upstreams as the receiving end of the tunnel, e.g. -d [ip:]port, The entire
local network is exposed through the tunnel if empty
-p, --password <PASSWORD>
Password of the tunnel server
-c, --cert <CERT>
Path to the certificate file in DER format, if empty, a self-signed certificate with the
domain "localhost" will be used [default: ]
-k, --key <KEY>
Path to the key file in DER format, can be empty if no cert is provided [default: ]
-t, --threads <THREADS>
Threads to run async tasks [default: 0]
-w, --max-idle-timeout-ms <MAX_IDLE_TIMEOUT_MS>
Max idle timeout for the connection [default: 40000]
-l, --loglevel <LOGLEVEL>
[default: I] [possible values: T, D, I, W, E]
-h, --help
Print help information
-V, --version
Print version information
- Complete options for
rstunc
USAGE:
rstunc [OPTIONS] --mode <MODE> --server-addr <SERVER_ADDR> --password <PASSWORD> --addr-mapping <ADDR_MAPPING>
OPTIONS:
-m, --mode <MODE>
Create a tunnel running in IN or OUT mode [possible values: IN, OUT]
-r, --server-addr <SERVER_ADDR>
Address (<domain:ip>[:port] pair) of rstund, default port is 3515
-p, --password <PASSWORD>
Password to connect with rstund
-a, --addr-mapping <ADDR_MAPPING>
LOCAL and REMOTE mapping in [ip:]port^[ip:]port format, e.g. 8080^0.0.0.0:9090
`ANY^8000` for not explicitly specifying a port for the local access server (the client)
`8000^ANY` for not explicitly specifying a port to bind with the remote server, the
server decides that port, so it depends on that the server is started with explicitly
setting the `--upstreams` option. `ANY^ANY` both the cases of the settings above
-c, --cert <CERT>
Path to the certificate file in DER format, only needed for self signed certificate
[default: ]
-e, --cipher <CIPHER>
Preferred cipher suite [default: chacha20-poly1305] [possible values: chacha20-poly1305,
aes-256-gcm, aes-128-gcm]
-t, --threads <THREADS>
Threads to run async tasks [default: 0]
-w, --wait-before-retry-ms <WAIT_BEFORE_RETRY_MS>
Wait time before trying [default: 5000]
-i, --max-idle-timeout-ms <MAX_IDLE_TIMEOUT_MS>
Max idle timeout for the connection [default: 30000]
-l, --loglevel <LOGLEVEL>
Log level [default: I] [possible values: T, D, I, W, E]
-h, --help
Print help information
-V, --version
Print version information
This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.