rathole

A secure, stable and high-performance reverse proxy for NAT traversal, written in Rust

rathole, like frp and ngrok, can help to expose the service on the device behind the NAT to the Internet, via a server with a public IP.

Features

• High Performance Much higher throughput can be achieved than frp. See Benchmark
• Low Resource Consumption Much less memory is consumed and well managed by Rust.
• Optimized Binary While small enough by default, rathole can be customized to be as small as ~500KiB to fit the constraints of devices, like embedded devices as routers.
• Secure Model Tokens of services are mandatory and service-wise. The server and clients are responsible for their own configs.
• Encryption With the help of the Noise Protocol, encryption can be configured at ease. No need to create a self-signed certificate! TLS is also supported.
• Hot Reload Services can be added or removed dynamically by hot-reloading the config file. HTTP API is WIP.

Quickstart

To use rathole, you need a server with a public IP, and a device behind the NAT, where some services that need to be exposed to the Internet.

Assuming you have a NAS at home behind the NAT, and want to expose its ssh service to the Internet:

1. On the server which has a public IP

Create server.toml with the following content and accommodate it to your needs.

# server.toml
[server]
bind_addr = "0.0.0.0:2333" # `2333` specifys the port that rathole listens for clients

[server.services.my_nas_ssh]
token = "use_a_secret_that_only_you_know" # Token that is used to authenticate the client for the service. Change to a arbitrary value.
bind_addr = "0.0.0.0:5202" # `5202` specifys the port that exposes `my_nas_ssh` to the Internet

Then run:

./rathole server.toml

2. On the host which is behind the NAT (your NAS)

Create client.toml with the following content and accommodate it to your needs.

[client]
remote_addr = "myserver.com:2333" # The address of the server. The port must be the same with the port in `server.bind_addr`

[client.services.my_nas_ssh]
token = "use_a_secret_that_only_you_know" # Must be the same with the server to pass the validataion
local_addr = "127.0.0.1:22" # The address of the service that needs to be forwarded

Then run:

./rathole client.toml

3. Now the client will try to connect to the server myserver.com on port 2333, and any traffic to myserver.com:5202 will be forwarded to the client's port 22.

So you can ssh myserver.com:5202 to ssh to your NAS.

Configuration

rathole can automatically determine to run in the server mode or the client mode, according to the content of the configuration file, if only one of [server] and [client] block is present, like the example in Quickstart.

But the [client] and [server] block can also be put in one file. Then on the server side, run rathole --server config.toml and on the client side, run rathole --client config.toml to explictly tell rathole the running mode.

Some configuration examples are provided under examples.

The Noise Protocol can be easily used to secure the traffic, see Security.

Here is the full configuration specification:

[client]
remote_addr = "example.com:2333" # Necessary. The address of the server
default_token = "default_token_if_not_specify" # Optional. The default token of services, if they don't define their own ones

[client.transport] # The whole block is optional. Specify which transport to use
type = "tcp" # Optional. Possible values: ["tcp", "tls", "noise"]. Default: "tcp"

[client.transport.tls] # Necessary if `type` is "tls"
trusted_root = "ca.pem" # Necessary. The certificate of CA that signed the server's certificate
hostname = "example.com" # Optional. The hostname that the client uses to validate the certificate. If not set, fallback to `client.remote_addr`

[client.transport.noise] # Noise protocol. See `docs/security.md` for further explanation
pattern = "Noise_NK_25519_ChaChaPoly_BLAKE2s" # Optional. Default value as shown
local_private_key = "key_encoded_in_base64" # Optional
remote_public_key = "key_encoded_in_base64" # Optional

[client.services.service1] # A service that needs forwarding. The name `service1` can change arbitrarily, as long as identical to the name in the server's configuration
type = "tcp" # Optional. The protocol that needs forwarding. Possible values: ["tcp", "udp"]. Default: "tcp"
token = "whatever" # Necessary if `client.default_token` not set
local_addr = "127.0.0.1:1081" # Necessary. The address of the service that needs to be forwarded

[client.services.service2] # Multiple services can be defined
local_addr = "127.0.0.1:1082"

[server]
bind_addr = "0.0.0.0:2333" # Necessary. The address that the server listens for clients. Generally only the port needs to be change. 
default_token = "default_token_if_not_specify" # Optional

[server.transport] # Same as `[client.transport]`
type = "tcp" 

[server.transport.tls] # Necessary if `type` is "tls"
pkcs12 = "identify.pfx" # Necessary. pkcs12 file of server's certificate and private key
pkcs12_password = "password" # Necessary. Password of the pkcs12 file

[server.transport.noise] # Same as `[client.transport.noise]`
pattern = "Noise_NK_25519_ChaChaPoly_BLAKE2s"
local_private_key = "key_encoded_in_base64" 
remote_public_key = "key_encoded_in_base64" 

[server.services.service1] # The service name must be identical to the client side
type = "tcp" # Optional. Same as the client `[client.services.X.type]
token = "whatever" # Necesary if `server.default_token` not set
bind_addr = "0.0.0.0:8081" # Necessary. The address of the service is exposed at. Generally only the port needs to be change. 

[server.services.service2] 
bind_addr = "0.0.0.1:8082"

Logging

rathole, like many other Rust programs, use environment variables to control the logging level. info, warn, error, debug, trace are avialable.

RUST_LOG=error ./rathole config.toml

will run rathole with only error level logging.

If RUST_LOG is not present, the default logging level is info.

Benchmark

rathole has similiar latency to frp, but can handle a more connections, provide larger bandwidth, with less memory usage.

See also Benchmark.

Development Status

rathole is under active development. A load of features is on the way:

• TLS support
• UDP support
• Hot reloading
• HTTP APIs for configuration