adjustment

README.md

@@ -11,7 +11,7 @@ go-realip
 [license]: https://github.com/natureglobal/go-realip/blob/master/LICENSE
 [godoc]: https://godoc.org/github.com/natureglobal/go-realip
 
-The go-realip detects RealIP in Go's http middleware layer.
+The go-realip detects client real ip in Go's HTTP middleware layer.
 
 ## Synopsis
 
@@ -30,7 +30,7 @@ handler = middleware(handler)
 
 ## Description
 
-The go-realip package implements detect clietn real IP from request headers in Go's http middleware layer.
+The go-realip package implements detecting client real IP mechanisms from request headers in Go's HTTP middleware layer.
 This have a similar behavior as Nginx's ngx\_http\_go-realip\_module
 
 ## Installation

realip.go

@@ -57,7 +57,7 @@ func (c *Config) handler(next http.Handler) http.Handler {
 	switch c.realIPHeader() {
 	case HeaderXForwardedFor:
 		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
-			if len(c.RealIPFrom) > 0 && !trustedIP(net.ParseIP(remoteIP(req.RemoteAddr)), c.RealIPFrom) {
+			if !trustedIP(net.ParseIP(remoteIP(req.RemoteAddr)), c.RealIPFrom) {
 				req.Header.Set(c.setHeader(), remoteIP(req.RemoteAddr))
 			} else {
 				realIP := realIPFromXFF(
@@ -73,7 +73,7 @@ func (c *Config) handler(next http.Handler) http.Handler {
 		})
 	default:
 		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
-			if len(c.RealIPFrom) > 0 && !trustedIP(net.ParseIP(remoteIP(req.RemoteAddr)), c.RealIPFrom) {
+			if !trustedIP(net.ParseIP(remoteIP(req.RemoteAddr)), c.RealIPFrom) {
 				req.Header.Set(c.setHeader(), remoteIP(req.RemoteAddr))
 			} else {
 				realIP := req.Header.Get(c.realIPHeader())
@@ -88,6 +88,9 @@ func (c *Config) handler(next http.Handler) http.Handler {
 }
 
 func trustedIP(ip net.IP, realIPFrom []*net.IPNet) bool {
+	if len(realIPFrom) == 0 {
+		return true
+	}
 	for _, fromIP := range realIPFrom {
 		if fromIP.Contains(ip) {
 			return true
@@ -124,5 +127,5 @@ func realIPFromXFF(xff string, realIPFrom []*net.IPNet, recursive bool) string {
 			return ipStr
 		}
 	}
-	return ""
+	return strings.TrimSpace(ips[0])
 }

realip_test.go

@@ -92,9 +92,31 @@ func TestMiddleware(t *testing.T) {
 			"X-Forwarded-For": "1.2.3.4, 1.1.1.1, 192.168.0.1",
 		},
 		expect: "127.0.0.1",
+	}, {
+		name: "x-forwarded-for: all entries in xff is trusted ip",
+		config: &realip.Config{
+			RealIPFrom: []*net.IPNet{
+				mustParseCIDR("127.0.0.1/32"),
+				mustParseCIDR("192.168.0.0/16"),
+			},
+			RealIPHeader:    realip.HeaderXForwardedFor,
+			RealIPRecursive: true,
+		},
+		headers: map[string]string{
+			"X-Forwarded-For": "192.168.0.2, 192.168.0.1",
+		},
+		expect: "192.168.0.2",
+	}, {
+		name: "x-forwarded-for: no RealIPFrom config and true RealIPRecursive return left entry in xff",
+		config: &realip.Config{
+			RealIPHeader:    realip.HeaderXForwardedFor,
+			RealIPRecursive: true,
+		},
+		headers: map[string]string{
+			"X-Forwarded-For": "192.168.0.2, 192.168.0.1",
+		},
+		expect: "192.168.0.2",
 	}}
-	// XXX: When RealIPFrom is empty and RealIPRecursive is true, I don't know what it
-	//      should do, so I don't test it.
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {