Fowarding to target website via a socks5 proxy.

[cvooc]

I found this extension module through google
https://caddy.community/t/fowarding-to-target-website-via-a-socks5-proxy/12349

I have the same requirement as the source, when I visit http://abc.com, it can send me through a specific socks5 proxy (like socks5://127.0.0.1:40000 of cf warp or shadowsocks/v2ray) Redirect to the target website, such as: https://xxx.com

I try to learn the configuration of this module, but I have no clue at all. The display in the readme is relatively simple. I can't understand what configuration I need to do. Can you help me?

My original configuration looks like this:

{
    "apps": {
        "http": {
            "servers": {
                "srv0": {
                    "listen": [":443"],
                    "routes": [{
                        "match": [{ "host": ["abc.com"] }],
                        "handle": [{
                            "handler": "subroute",
                            "routes": [{
                                "handle": [{
                                    "handler": "reverse_proxy",
                                    "headers": { "request": { "set": { "Host": ["{http.reverse_proxy.upstream.hostport}"] } } },
                                    "upstreams": [{ "dial": "xxx.com:80" }]
                                }]
                            }]
                        }],
                        "terminal": true
                    }]
                }
            }
        }
    }
}

[mholt]

Hi there, good question. Sorry this module is still a bit sparse on docs/examples.

However, did you know we have an interactive docs explorer at https://caddyserver.com/docs/json/apps/layer4 ? -- you can traverse the JSON structure there. Does that help?

[vnxme]

The short answer is no, the Layer 4 app isn't currently capable of using SOCKS5 proxies while proxying any traffic. Neither is Caddy, as far as I know.

However, it's possible to overcome this limitation if you make your machine that has Caddy running intercept and route certain traffic over external proxies.

While the requested functionality isn't implemented yet, the general idea would be to extend the proxy handler to let the user configure custom dialers here.

Then SOCKS5 could be one of such dialers (as suggested by Gemini):

package main

import (
    "fmt"
    "io"
    "log"
    "net"
    "golang.org/x/net/proxy"
)

func main() {
    // 1. Define the SOCKS5 proxy address and the target address.
    // Replace these with your actual proxy and destination addresses.
    proxyAddress := "127.0.0.1:1080"
    targetAddress := "example.com:80" // or any other TCP service, e.g., "google.com:443" for HTTPS

    // Optional: SOCKS5 authentication (nil if no auth is required)
    var auth *proxy.Auth = nil
    /* 
    // Example with authentication:
    auth = &proxy.Auth{
        User:     "myuser",
        Password: "mypassword",
    }
    */

    // 2. Create the SOCKS5 dialer.
    // proxy.Direct is used as the "forward" dialer, which is the ultimate
    // dialer used if no proxy is needed (or in this case, to establish the 
    // initial TCP connection to the proxy server itself).
    dialer, err := proxy.SOCKS5("tcp", proxyAddress, auth, proxy.Direct)
    if err != nil {
        log.Fatalf("can't connect to the proxy: %v", err)
    }

    // 3. Use the SOCKS5 dialer's Dial method instead of net.Dial.
    // This dialer handles the SOCKS5 handshake before returning the connection.
    conn, err := dialer.Dial("tcp", targetAddress)
    if err != nil {
        log.Fatalf("can't dial through proxy: %v", err)
    }
    defer conn.Close()

    fmt.Printf("Successfully connected to %s via SOCKS5 proxy!\n", targetAddress)

    // Example of using the connection (e.g., sending an HTTP GET request manually)
    fmt.Fprintf(conn, "GET / HTTP/1.1\r\nHost: example.com\r\n\r\n")
    io.Copy(io.Stdout, conn)
}