Merge pull request #27 from Snawoot/socket_activation

Socket activation

Author: Snawoot

README.md

@@ -18,6 +18,7 @@ Dumbest HTTP proxy ever.
 * Supports HTTP/2
 * Resilient to DPI (including active probing, see `hidden_domain` option for authentication providers)
 * Connecting via upstream HTTP(S)/SOCKS5 proxies (proxy chaining)
+* systemd socket activation
 
 ## Installation
 
@@ -184,7 +185,7 @@ Usage of /home/user/go/bin/dumbproxy:
   -autocert-whitelist value
     	restrict autocert domains to this comma-separated list
   -bind-address string
-    	HTTP proxy listen address (default ":8080")
+    	HTTP proxy listen address. Set empty value to use systemd socket activation. (default ":8080")
   -cafile string
     	CA file to authenticate clients with certificates
   -cert string

go.mod

@@ -4,6 +4,7 @@ go 1.13
 
 require (
 	github.com/GehirnInc/crypt v0.0.0-20230320061759-8cc1b52080c5 // indirect
+	github.com/coreos/go-systemd/v22 v22.5.0 // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/tg123/go-htpasswd v1.2.1
 	golang.org/x/crypto v0.7.0

go.sum

@@ -1,10 +1,13 @@
 github.com/GehirnInc/crypt v0.0.0-20200316065508-bb7000b8a962/go.mod h1:kC29dT1vFpj7py2OvG1khBdQpo3kInWP+6QipLbdngo=
 github.com/GehirnInc/crypt v0.0.0-20230320061759-8cc1b52080c5 h1:IEjq88XO4PuBDcvmjQJcQGg+w+UaafSy8G5Kcb5tBhI=
 github.com/GehirnInc/crypt v0.0.0-20230320061759-8cc1b52080c5/go.mod h1:exZ0C/1emQJAw5tHOaUDyY1ycttqBAPcxuzf7QbY6ec=
+github.com/coreos/go-systemd/v22 v22.5.0 h1:RrqgGjYQKalulkV8NGVIfkXQf6YYmOyiJKk8iXXhfZs=
+github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
 github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
 github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=

main.go

@@ -12,6 +12,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/coreos/go-systemd/v22/activation"
 	"golang.org/x/crypto/acme"
 	"golang.org/x/crypto/acme/autocert"
 	"golang.org/x/crypto/bcrypt"
@@ -75,7 +76,7 @@ type CLIArgs struct {
 
 func parse_args() CLIArgs {
 	var args CLIArgs
-	flag.StringVar(&args.bind_address, "bind-address", ":8080", "HTTP proxy listen address")
+	flag.StringVar(&args.bind_address, "bind-address", ":8080", "HTTP proxy listen address. Set empty value to use systemd socket activation.")
 	flag.StringVar(&args.auth, "auth", "none://", "auth parameters")
 	flag.IntVar(&args.verbosity, "verbosity", 20, "logging verbosity "+
 		"(10 - debug, 20 - info, 30 - warning, 40 - error, 50 - critical)")
@@ -170,14 +171,40 @@ func run() int {
 	}
 
 	mainLogger.Info("Starting proxy server...")
+	var listener net.Listener
+	if args.bind_address == "" {
+		// socket activation
+		listeners, err := activation.Listeners()
+		if err != nil {
+			mainLogger.Critical("socket activation failed: %v", err)
+			return 3
+		}
+		if len(listeners) != 1 {
+			mainLogger.Critical("socket activation failed: unexpected number of listeners: %d",
+				len(listeners))
+			return 3
+		}
+		if listeners[0] == nil {
+			mainLogger.Critical("socket activation failed: nil listener returned")
+			return 3
+		}
+		listener = listeners[0]
+	} else {
+		newListener, err := net.Listen("tcp", args.bind_address)
+		if err != nil {
+			mainLogger.Critical("listen failed: %v", err)
+			return 3
+		}
+		listener = newListener
+	}
+
 	if args.cert != "" {
-		cfg, err1 := makeServerTLSConfig(args.cert, args.key, args.cafile, args.ciphers)
+		cfg, err1 := makeServerTLSConfig(args.cert, args.key, args.cafile, args.ciphers, !args.disableHTTP2)
 		if err1 != nil {
 			mainLogger.Critical("TLS config construction failed: %v", err1)
 			return 3
 		}
-		server.TLSConfig = cfg
-		err = server.ListenAndServeTLS("", "")
+		listener = tls.NewListener(listener, cfg)
 	} else if args.autocert {
 		m := &autocert.Manager{
 			Cache:  autocert.DirCache(args.autocertDir),
@@ -195,18 +222,15 @@ func run() int {
 			}()
 		}
 		cfg := m.TLSConfig()
-		cfg, err = updateServerTLSConfig(cfg, args.cafile, args.ciphers)
+		cfg, err = updateServerTLSConfig(cfg, args.cafile, args.ciphers, !args.disableHTTP2)
 		if err != nil {
 			mainLogger.Critical("TLS config construction failed: %v", err)
 			return 3
 		}
-		server.TLSConfig = cfg
-		err = server.ListenAndServeTLS("", "")
-		mainLogger.Info("Proxy server started.")
-	} else {
-		mainLogger.Info("Proxy server started.")
-		err = server.ListenAndServe()
+		listener = tls.NewListener(listener, cfg)
 	}
+	mainLogger.Info("Proxy server started.")
+	err = server.Serve(listener)
 	mainLogger.Critical("Server terminated with a reason: %v", err)
 	mainLogger.Info("Shutting down...")
 	return 0

utils.go

@@ -151,7 +151,7 @@ func copyBody(wr io.Writer, body io.Reader) {
 	}
 }
 
-func makeServerTLSConfig(certfile, keyfile, cafile, ciphers string) (*tls.Config, error) {
+func makeServerTLSConfig(certfile, keyfile, cafile, ciphers string, h2 bool) (*tls.Config, error) {
 	var cfg tls.Config
 	cert, err := tls.LoadX509KeyPair(certfile, keyfile)
 	if err != nil {
@@ -171,10 +171,13 @@ func makeServerTLSConfig(certfile, keyfile, cafile, ciphers string) (*tls.Config
 		cfg.ClientAuth = tls.VerifyClientCertIfGiven
 	}
 	cfg.CipherSuites = makeCipherList(ciphers)
+	if h2 {
+		cfg.NextProtos = []string{"h2", "http/1.1"}
+	}
 	return &cfg, nil
 }
 
-func updateServerTLSConfig(cfg *tls.Config, cafile, ciphers string) (*tls.Config, error) {
+func updateServerTLSConfig(cfg *tls.Config, cafile, ciphers string, h2 bool) (*tls.Config, error) {
 	if cafile != "" {
 		roots := x509.NewCertPool()
 		certs, err := ioutil.ReadFile(cafile)
@@ -188,6 +191,9 @@ func updateServerTLSConfig(cfg *tls.Config, cafile, ciphers string) (*tls.Config
 		cfg.ClientAuth = tls.VerifyClientCertIfGiven
 	}
 	cfg.CipherSuites = makeCipherList(ciphers)
+	if h2 {
+		cfg.NextProtos = []string{"h2", "http/1.1"}
+	}
 	return cfg, nil
 }