Cloak is a universal pluggable transport that obfuscates proxy traffic as legitimate HTTPS traffic, disguises the proxy server as a normal web server, multiplexes traffic through multiple TCP connections and provide multi-user usage control.
Cloak eliminates any "fingerprints" exposed by traditional proxy protocol designs which can be identified by adversaries through deep packet inspection. If a non-Cloak program or an unauthorised Cloak user (such as an adversary's prober) attempts to connect to Cloak server, it will serve as a transparent proxy between said machine and an ordinary website, so that to any unauthorised third party, a host running Cloak server is indistinguishable from an innocent web server.
Since Cloak is transparent, it can be used in conjunction with any proxy software that tunnels traffic through TCP, such as Shadowsocks, OpenVPN and Tor. Multiple proxy servers can be running on the same server host machine and Cloak will act as a dispatcher, bridging clients with their desired proxy end.
Cloak provides multi-user support, allowing multiple clients to connect to the proxy server on the same port (443 by default). It also provides QoS controls for individual users such as data usage limit and bandwidth control.
**Cloak 2.x is not compatible with legacy Cloak 1.x's protocol, configuration file or database file. Cloak 1.x protocol has critical cryptographic flaws regarding encrypting stream headers. Using Cloak 1.x is strongly discouraged**
This project is based on [GoQuiet](https://github.com/cbeuw/GoQuiet). Through multiplexing, Cloak provides a siginifcant reduction in webpage loading time compared to GoQuiet (from 10% to 50%+, depending on the amount of content on the webpage, see [benchmarks](https://github.com/cbeuw/Cloak/wiki/Web-page-loading-benchmarks)).
`RedirAddr` is the redirection address and port when the incoming traffic is not from a Cloak client. It should correspond to the IP record of the `ServerName` field set in `ckclient.json`.
`ProxyBook` is a nested JSON section which defines the address of different proxy server ends. For instance, if OpenVPN server is listening on 127.0.0.1:1194, the pair should be `"openvpn":"127.0.0.1:1194"`. There can be multiple pairs. You can add any other proxy server in a similar fashion, as long as the name matches the `ProxyMethod` in the client config exactly (case-sensitive).
`DatabasePath` is the path to userinfo.db. If userinfo.db doesn't exist in this directory, Cloak will create one automatically. **If Cloak is started as a Shadowsocks plugin and Shadowsocks is started with its working directory as / (e.g. starting ss-server with systemctl), you need to set this field as an absolute path to a desired folder. If you leave it as default then Cloak will attempt to create userinfo.db under /, which it doesn't have the permission to do so and will raise an error. See Issue #13.**
`EncryptionMethod` is the name of the encryption algorithm you want Cloak to use. Note: Cloak isn't intended to provide data encryption. The point of encryption is to hide fingerprints of proxy protocols. If the proxy protocol is already fingerprint-less, which is the case for Shadowsocks, this field can be left as `plain`. Options are `plain`, `aes-gcm` and `chacha20-poly1305`.
`NumConn` is the amount of underlying TCP connections you want to use. The default of 4 should be appropriate for most people. Setting it too high will hinder the performance.
`BrowserSig` is the browser you want to **appear** to be using. It's not relevant to the browser you are actually using. Currently, `chrome` and `firefox` are supported.
0. Set up the underlying proxy server. Note that if you are using OpenVPN, you must change the protocol to TCP as Cloak does not support UDP
1. Download [the latest release](https://github.com/cbeuw/Cloak/releases) or clone and build this repo. If you wish to build it, make sure you fetch the dependencies using `go get github.com/boltdb/bolt`, `go get github.com/juju/ratelimit` and `go get github.com/gorilla/mux`
2. Run ck-server -k. The base64 string before the comma is the **public** key to be given to users, the one after the comma is the **private** key to be kept secret
4. Copy example_config/ckserver.json into a desired location. Change `PrivateKey` to the private key you just obtained; change `AdminUID` to the UID you just obtained.
5. Configure your underlying proxy server so that they all listen on localhost. Edit `ProxyBook` in the configuration file accordingly
6. [Configure the proxy program.](https://github.com/cbeuw/Cloak/wiki/Underlying-proxy-configuration-guides) Run `sudo ck-server -c <path to ckserver.json>`. ck-server needs root privilege because it binds to a low numbered port (443). Alternatively you can follow https://superuser.com/a/892391 to avoid granting ck-server root privilege unnecessarily.
1. On your client, run `ck-client -s <IP of the server> -l <A local port> -a <AdminUID> -c <path-to-ckclient.json>` to enter admin mode
2. Visit https://cbeuw.github.io/Cloak-panel (Note: this is a static site, there is no backend and all data entered into this site are processed between your browser and the Cloak API endpoint you specified. Alternatively you can download the repo at https://github.com/cbeuw/Cloak-panel and host it on your own web server).
3. Type in 127.0.0.1:<theportyouenteredinstep1> as the API Base, and click `List`.
4. You can add in more users by clicking the `+` panel
0. Install and configure the proxy client based on the server
1. Download [the latest release](https://github.com/cbeuw/Cloak/releases) or clone and build this repo. If you wish to build it, make sure you fetch the dependencies using `go get github.com/boltdb/bolt`, `go get github.com/juju/ratelimit` and `go get github.com/gorilla/mux`
3. Copy example_config/ckclient.json into a location of your choice. Enter the `UID` and `PublicKey` you have obtained. Set `ProxyMethod` to match exactly the corresponding entry in `ProxyBook` on the server end
4. [Configure the proxy program.](https://github.com/cbeuw/Cloak/wiki/Underlying-proxy-configuration-guides) Run `ck-client -c <path to ckclient.json> -s <ip of your server>`
