Add support for client certificates when connecting to upstream networks

Author: ItsOnlyBinary

config.conf.example

@@ -10,6 +10,10 @@ gateway_name = "webircgateway"
 # A secret string used for generating client JWT tokens. Do not share this!
 secret = ""
 
+# Webirc client certificate sent to servers when connecting with TLS
+webirc_cert = ""
+webirc_key = ""
+
 # Send the server a quit message when the client is closed
 # Comment out to disable
 send_quit_on_client_close = "Client closed"

pkg/proxy/server.go

@@ -36,19 +36,24 @@ type HandshakeMeta struct {
 	Interface string `json:"interface"`
 }
 
-func MakeClient(conn net.Conn) *Client {
-	return &Client{
+func MakeClient(conn net.Conn, webircCert *tls.Certificate) *Client {
+	client := &Client{
 		Client: conn,
 	}
+	if webircCert != nil {
+		client.WebircCertificate = []tls.Certificate{*webircCert}
+	}
+	return client
 }
 
 type Client struct {
-	Client       net.Conn
-	Upstream     net.Conn
-	UpstreamAddr *net.TCPAddr
-	Username     string
-	BindAddr     *net.TCPAddr
-	TLS          bool
+	Client            net.Conn
+	Upstream          net.Conn
+	UpstreamAddr      *net.TCPAddr
+	Username          string
+	BindAddr          *net.TCPAddr
+	TLS               bool
+	WebircCertificate []tls.Certificate
 }
 
 func (c *Client) Run() {
@@ -185,7 +190,7 @@ func (c *Client) Pipe() {
 	}
 }
 
-func Start(laddr string) {
+func Start(laddr string, webircCert *tls.Certificate) {
 	srv, err := net.Listen("tcp", laddr)
 	if err != nil {
 		log.Fatal(err.Error())
@@ -205,7 +210,7 @@ func Start(laddr string) {
 			break
 		}
 
-		c := MakeClient(conn)
+		c := MakeClient(conn, webircCert)
 		go c.Run()
 	}
 }

pkg/webircgateway/client.go

@@ -343,7 +343,10 @@ func (c *Client) makeUpstreamConnection() (io.ReadWriteCloser, error) {
 		}
 
 		if upstreamConfig.TLS {
-			tlsConfig := &tls.Config{InsecureSkipVerify: true}
+			tlsConfig := &tls.Config{
+				InsecureSkipVerify: true,
+				Certificates:       upstreamConfig.WebircCertificate,
+			}
 			tlsConn := tls.Client(conn, tlsConfig)
 			err := tlsConn.Handshake()
 			if err != nil {
@@ -697,6 +700,11 @@ func (c *Client) configureUpstream() ConfigUpstream {
 	upstreamConfig.Throttle = c.Gateway.Config.GatewayThrottle
 	upstreamConfig.WebircPassword = c.Gateway.findWebircPassword(c.DestHost)
 
+	if upstreamConfig.WebircPassword != "" && c.Gateway.Config.WebircCert != nil {
+		upstreamConfig.WebircCertificate = []tls.Certificate{
+			*c.Gateway.Config.WebircCert,
+		}
+	}
 	return upstreamConfig
 }
 

pkg/webircgateway/config.go

@@ -1,6 +1,7 @@
 package webircgateway
 
 import (
+	"crypto/tls"
 	"errors"
 	"net"
 	"os"
@@ -27,6 +28,7 @@ type ConfigUpstream struct {
 	ServerPassword       string
 	GatewayName          string
 	Proxy                *ConfigProxy
+	WebircCertificate    []tls.Certificate
 }
 
 // ConfigServer - A web server config
@@ -77,6 +79,7 @@ type Config struct {
 	ReCaptchaSecret       string
 	ReCaptchaKey          string
 	Secret                string
+	WebircCert            *tls.Certificate
 	Plugins               []string
 	DnsblServers          []string
 	// DnsblAction - "deny" = deny the connection. "verify" = require verification
@@ -148,6 +151,7 @@ func (c *Config) Load() error {
 	c.ReCaptchaKey = ""
 	c.RequiresVerification = false
 	c.Secret = ""
+	c.WebircCert = nil
 	c.SendQuitOnClientClose = ""
 	c.ClientRealname = ""
 	c.ClientUsername = ""
@@ -172,6 +176,20 @@ func (c *Config) Load() error {
 			}
 
 			c.Secret = section.Key("secret").MustString("")
+
+			// Load webirc client certificate
+			webircCert := section.Key("webirc_cert").MustString("")
+			webircKey := section.Key("webirc_key").MustString("")
+			if webircCert != "" && webircKey != "" {
+				certPath := c.ResolvePath(webircCert)
+				keyPath := c.ResolvePath(webircKey)
+				webircCert, err := tls.LoadX509KeyPair(certPath, keyPath)
+				if err == nil {
+					c.WebircCert = &webircCert
+				} else {
+					c.gateway.Log(3, "Failed to load webirc certificate, "+err.Error())
+				}
+			}
 			c.SendQuitOnClientClose = section.Key("send_quit_on_client_close").MustString("Connection closed")
 		}
 

pkg/webircgateway/gateway.go

@@ -78,7 +78,10 @@ func (s *Gateway) Start() {
 	}
 
 	if s.Function == "proxy" {
-		proxy.Start(fmt.Sprintf("%s:%d", s.Config.Proxy.LocalAddr, s.Config.Proxy.Port))
+		proxy.Start(
+			fmt.Sprintf("%s:%d", s.Config.Proxy.LocalAddr, s.Config.Proxy.Port),
+			s.Config.WebircCert,
+		)
 	}
 }