Proxy with protocol "socks4"and "socks5" cant be used on version `0.5.4`

[amoguslmao]

📝 Summary

Version 0.5.4 cannot use proxies with the socks4 or socks5 protocol and throws an error, while version 0.5.3 works normally and responds properly.

📖 Description

I used NPM to install the latest version of Impit with the command:

npm install impit

After installing, I started using the package normally. However, after a while, I noticed that I couldn’t use proxies with the socks4 or socks5 protocol anymore. I double-checked multiple times to make sure the proxy was still alive and not dead.

When I used a proxy with that protocol, I got an error like this:

PS C:\Users\admin\Documents\Coding\impit-test> node .
[Error: impit error: The internal HTTP library has thrown an error:
reqwest::Error {
    kind: Request,
    url: "https://backend.wplace.live/me",
    source: hyper_util::client::legacy::Error(
        Connect,
        SocksConnect(
            Inner(
                ConnectError(
                    "tcp connect error",
                    113.169.74.21:10012,
                    Os {
                        code: 10060,
                        kind: TimedOut,
                        message: "A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.",     
                    },
                ),
            ),
        ),
    ),
}] {
  code: 'GenericFailure'
}

At that time, my code looked like this:

import { Impit } from "impit";
import { CookieJar } from "tough-cookie";

const COOKIE = "deleted the cookie";

try {
	const cookie = new CookieJar();
	await cookie.setCookie(`j=${COOKIE}; Path=/`, "https://backend.wplace.live");

	const impit = new Impit({
		browser: "chrome",
		proxyUrl: "socks4://113.169.74.21:10012",
		timeout: 30000,
		ignoreTlsErrors: true,
		cookieJar: cookie
	});

	const res = await impit.fetch("https://backend.wplace.live/me");

	console.log(await res.json());
}
catch(err) {
	console.error(err);
}

After repeatedly checking and asking GPT as well as searching on Google, and even looking through StackOverflow, I couldn’t find any information related to the Impit package 😥. Then I remembered there was a repo also using this package that worked fine. I went into their package.json and saw that they were on version 0.5.3. I followed and installed version 0.5.3 like this:

npm install impit@0.5.3

After installing, I tried using the same proxy again and... surprisingly! Impit fetched successfully without throwing any errors.

I’m not sure if anyone has already opened an issue like this, so please excuse me if this is a duplicate.
i used gpt to translate the issues to english

[barjin]

Hi @IamsadVN, thank you for your interest in this project!

Until 0.5.4, impit (via its upstream dependencies) did not actually support SOCKS4 proxies correctly. When you passed a socks4:// proxy, the traffic was not routed through the proxy at all - it was connecting directly to the target server. I confirmed this with Wireshark captures and also with the new tests we just added: #268.

This means that in your script, what seemed like working SOCKS4 proxy support in 0.5.3 was in fact just a direct connection. In 0.5.4, the behavior was fixed, so SOCKS4 proxies are now handled properly. If the proxy you’re trying doesn’t support SOCKS4 correctly (or has connectivity issues), you’ll now see connection errors instead of a silent fallback.

If you’d like to double-check your proxy, you can test it with a standalone tool like:

curl --socks4 <ip:port> https://targetserver.com

(or --socks5 for SOCKS5). That way, you’ll know for sure whether the proxy and the target server are alive and responding.

Since this is the intended behavior after the fix, I’ll go ahead and close this issue. Thank you for bringing this up.