Add new REQUIRE_AUTH config parameter, to disable running socks5 server without auth by default

.env.example

@@ -1,3 +1,2 @@
 PROXY_USER=someuser
 PROXY_PASSWORD=somepass
-PROXY_PORT=1080

README.md

@@ -1,7 +1,6 @@
 # go-socks5-proxy
 
 ![Latest tag from master branch](https://github.com/serjs/socks5-server/workflows/Latest%20tag%20from%20master%20branch/badge.svg)
-![Release tag](https://github.com/serjs/socks5-server/workflows/Release%20tag/badge.svg)
 
 Simple socks5 server using go-socks5 with authentication, allowed ips list and destination FQDNs filtering
 
@@ -11,16 +10,15 @@ Simple socks5 server using go-socks5 with authentication, allowed ips list and d
 
     ```docker run -d --name socks5 -p 1080:1080 -e PROXY_USER=<PROXY_USER> -e PROXY_PASSWORD=<PROXY_PASSWORD>  serjs/go-socks5-proxy```
 
-    - Leave `PROXY_USER` and `PROXY_PASSWORD` empty for skip authentication options while running socks5 server, see example below
+- Run docker container using specific container port and expose it to host port 1090
 
-- Run docker container using specifit container port and expose it to host port 1090, without auth creds
+    ```docker run -d --name socks5 -p 1090:9090 -e PROXY_USER=<PROXY_USER> -e PROXY_PASSWORD=<PROXY_PASSWORD> -e PROXY_PORT=9090 serjs/go-socks5-proxy```
-
-    ```docker run -d --name socks5 -p 1090:9090 -e PROXY_PORT=9090 serjs/go-socks5-proxy```
 
 # List of supported config parameters
 
 |ENV variable|Type|Default|Description|
 |------------|----|-------|-----------|
+|REQUIRE_AUTH|String|true|Allow accepting socks5 connections without auth creds. Not recommended untill you use other protections mechanisms like Whitelists Subnets using Firewall or Proxy itself|
 |PROXY_USER|String|EMPTY|Set proxy user (also required existed PROXY_PASS)|
 |PROXY_PASSWORD|String|EMPTY|Set proxy password for auth, used with PROXY_USER|
 |PROXY_PORT|String|1080|Set listen port for application inside docker container|
@@ -30,7 +28,7 @@ Simple socks5 server using go-socks5 with authentication, allowed ips list and d
 
 # Build your own image:
 `docker-compose -f docker-compose.build.yml up -d`\
-Just don't forget to set parameters in the `.env` file.
+Just don't forget to set parameters in the `.env` file (`cp .env.example .env)` and edit it with your config parameters
 
 # Test running service
 
@@ -38,19 +36,19 @@ Assuming that you are using container on 1080 host docker port
 
 ## Without authentication
 
-```curl --socks5 <docker host ip>:1080  https://ifcfg.co``` - result must show docker host ip (for bridged network)
+```curl --socks5 <docker host ip>:1080  https://ipinfo.io``` - result must show docker host ip (for bridged network)
 
 or
 
-```docker run --rm curlimages/curl:7.65.3 -s --socks5 <docker host ip>:1080 https://ifcfg.co```
+```docker run --rm curlimages/curl:7.65.3 -s --socks5 <docker host ip>:1080 https://ipinfo.io```
 
 ## With authentication
 
-```curl --socks5 <docker host ip>:1080 -U <PROXY_USER>:<PROXY_PASSWORD> http://ifcfg.co```
+```curl --socks5 <docker host ip>:1080 -U <PROXY_USER>:<PROXY_PASSWORD> https://ipinfo.io```
 
 or
 
-```docker run --rm curlimages/curl:7.65.3 -s --socks5 <PROXY_USER>:<PROXY_PASSWORD>@<docker host ip>:1080 http://ifcfg.co```
+```docker run --rm curlimages/curl:7.65.3 -s --socks5 <PROXY_USER>:<PROXY_PASSWORD>@<docker host ip>:1080 https://ipinfo.io```
 
 # Authors
 

server.go

@@ -14,7 +14,8 @@ type params struct {
 	Port            string    `env:"PROXY_PORT" envDefault:"1080"`
 	AllowedDestFqdn string    `env:"ALLOWED_DEST_FQDN" envDefault:""`
 	AllowedIPs      []string  `env:"ALLOWED_IPS" envSeparator:"," envDefault:""`
-	ListenIP string `env:"PROXY_LISTEN_IP" envDefault:"0.0.0.0"`
+	ListenIP 		string 	  `env:"PROXY_LISTEN_IP" envDefault:"0.0.0.0"`
+	RequireAuth		bool      `env:"REQUIRE_AUTH" envDefault:"true"`
 }
 
 func main() {
@@ -30,12 +31,17 @@ func main() {
 		Logger: log.New(os.Stdout, "", log.LstdFlags),
 	}
 
-	if cfg.User+cfg.Password != "" {
+	if cfg.RequireAuth {
+		if cfg.User == "" || cfg.Password == "" {
+			log.Fatalln("Error: REQUIRE_AUTH is true, but PROXY_USER and PROXY_PASSWORD are not set.  The application will now exit.")
+		}
 		creds := socks5.StaticCredentials{
-			os.Getenv("PROXY_USER"): os.Getenv("PROXY_PASSWORD"),
+			cfg.User: cfg.Password,
 		}
 		cator := socks5.UserPassAuthenticator{Credentials: creds}
 		socks5conf.AuthMethods = []socks5.Authenticator{cator}
+	} else {
+		log.Println("Warning: Running the proxy server without authentication. This is NOT recommended for public servers.")
 	}
 
 	if cfg.AllowedDestFqdn != "" {