Merge pull request #2942 from getlantern/issue2941

Report and use IP and country from CloudFlare closes #2941

src/github.com/getlantern/enproxy/proxy.go

@@ -130,6 +130,9 @@ func (p *Proxy) Serve(l net.Listener) error {
 
 // ServeHTTP: implements the http.Handler interface
 func (p *Proxy) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
+	resp.Header().Set("Lantern-IP", req.Header.Get("X-Forwarded-For"))
+	resp.Header().Set("Lantern-Country", req.Header.Get("Cf-Ipcountry"))
+
 	if req.Method == "HEAD" {
 		// Just respond OK to HEAD requests (used for health checks)
 		resp.WriteHeader(200)

src/github.com/getlantern/enproxy/proxy_test.go

@@ -0,0 +1,39 @@
+package enproxy
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestCustomHeaders(t *testing.T) {
+
+	proxy := &Proxy{}
+
+	w := httptest.NewRecorder()
+
+	req, err := http.NewRequest("GET", "http://example.com/foo", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	xff := "7.7.7.7"
+	req.Header.Set("X-Forwarded-For", xff)
+
+	ipc := "US"
+	req.Header.Set("Cf-Ipcountry", ipc)
+
+	proxy.ServeHTTP(w, req)
+
+	ip := w.Header().Get("Lantern-IP")
+	country := w.Header().Get("Lantern-Country")
+
+	log.Debugf("Testing IP: %v", ip)
+	log.Debugf("Testing country: %v", country)
+	if ip != xff {
+		t.Fatalf("Unexpected ip: %v", ip)
+	}
+	if country != ipc {
+		t.Fatalf("Unexpected country: %v", country)
+	}
+}

src/github.com/getlantern/flashlight/server/server.go

@@ -271,10 +271,34 @@ func (server *Server) checkForDisallowedPort(addr string) error {
 }
 
 func (server *Server) checkForBannedCountry(req *http.Request) error {
+	country := req.Header.Get("Cf-Ipcountry")
+	if country == "" {
+		var err error
+		if country, err = server.lookupCountry(req); err != nil {
+			log.Errorf("Could not find country %v", err)
+			return nil
+		}
+	}
+
+	countryBanned := false
+	for _, banned := range server.BannedCountries {
+		if country == strings.ToUpper(banned) {
+			countryBanned = true
+			break
+		}
+	}
+	if countryBanned {
+		return fmt.Errorf("Not accepting connections from country %v", country)
+	}
+
+	return nil
+}
+
+func (server *Server) lookupCountry(req *http.Request) (string, error) {
 	clientIp := getClientIp(req)
 	if clientIp == "" {
 		log.Debug("Unable to determine client ip for geolookup")
-		return nil
+		return "", nil
 	}
 
 	country := ""
@@ -287,24 +311,12 @@ func (server *Server) checkForBannedCountry(req *http.Request) error {
 		city, _, err := geolookup.LookupIPWithClient(clientIp, nil)
 		if err != nil {
 			log.Debugf("Unable to perform geolookup for ip %v: %v", clientIp, err)
-			return nil
+			return country, err
 		}
 		country = strings.ToUpper(city.Country.IsoCode)
 		server.geoCache.Add(clientIp, country)
 	}
-
-	countryBanned := false
-	for _, banned := range server.BannedCountries {
-		if country == strings.ToUpper(banned) {
-			countryBanned = true
-			break
-		}
-	}
-	if countryBanned {
-		return fmt.Errorf("Not accepting connections from country %v", country)
-	}
-
-	return nil
+	return country, nil
 }
 
 func mapPort(addr string, port int) error {

src/github.com/getlantern/flashlight/server/server_test.go

@@ -0,0 +1,40 @@
+package server
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/getlantern/fronted"
+)
+
+func TestBanned(t *testing.T) {
+
+	srv := &Server{
+		Addr:         "127.0.0.1",
+		ReadTimeout:  0, // don't timeout
+		WriteTimeout: 0,
+		CertContext:  &fronted.CertContext{},
+		AllowedPorts: []int{80, 443, 8080, 8443, 5222, 5223, 5228},
+
+		// We've observed high resource consumption from these countries for
+		// purposes unrelated to Lantern's mission, so we disallow them.
+		BannedCountries: []string{"PH"},
+	}
+
+	req, err := http.NewRequest("GET", "http://test.com/foo", nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+	req.Header.Set("Cf-Ipcountry", "PH")
+
+	err = srv.checkForBannedCountry(req)
+	if err == nil {
+		t.Fatalf("Should be banned: %v", err)
+	}
+
+	req.Header.Set("Cf-Ipcountry", "US")
+	err = srv.checkForBannedCountry(req)
+	if err != nil {
+		t.Fatalf("Should not be banned: %v", err)
+	}
+}

testpackages.txt

@@ -14,6 +14,7 @@ github.com/getlantern/fdcount
 github.com/getlantern/flashlight
 github.com/getlantern/flashlight/logging
 github.com/getlantern/flashlight/pubsub
+github.com/getlantern/flashlight/server
 github.com/getlantern/flashlight/statreporter
 github.com/getlantern/fronted
 github.com/getlantern/geolookup