init

at-server/vendor/github.com/vulcand/oxy/forward/rewrite.go

@@ -0,0 +1,92 @@
+package forward
+
+import (
+	"net"
+	"net/http"
+	"strings"
+
+	"github.com/vulcand/oxy/utils"
+)
+
+// HeaderRewriter is responsible for removing hop-by-hop headers and setting forwarding headers
+type HeaderRewriter struct {
+	TrustForwardHeader bool
+	Hostname           string
+}
+
+// clean up IP in case if it is ipv6 address and it has {zone} information in it, like "[fe80::d806:a55d:eb1b:49cc%vEthernet (vmxnet3 Ethernet Adapter - Virtual Switch)]:64692"
+func ipv6fix(clientIP string) string {
+	return strings.Split(clientIP, "%")[0]
+}
+
+// Rewrite rewrite request headers
+func (rw *HeaderRewriter) Rewrite(req *http.Request) {
+	if !rw.TrustForwardHeader {
+		utils.RemoveHeaders(req.Header, XHeaders...)
+	}
+
+	if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
+		clientIP = ipv6fix(clientIP)
+		// If not websocket, done in http.ReverseProxy
+		if IsWebsocketRequest(req) {
+			if prior, ok := req.Header[XForwardedFor]; ok {
+				req.Header.Set(XForwardedFor, strings.Join(prior, ", ")+", "+clientIP)
+			} else {
+				req.Header.Set(XForwardedFor, clientIP)
+			}
+		}
+
+		if req.Header.Get(XRealIp) == "" {
+			req.Header.Set(XRealIp, clientIP)
+		}
+	}
+
+	xfProto := req.Header.Get(XForwardedProto)
+	if xfProto == "" {
+		if req.TLS != nil {
+			req.Header.Set(XForwardedProto, "https")
+		} else {
+			req.Header.Set(XForwardedProto, "http")
+		}
+	}
+
+	if IsWebsocketRequest(req) {
+		if req.Header.Get(XForwardedProto) == "https" {
+			req.Header.Set(XForwardedProto, "wss")
+		} else {
+			req.Header.Set(XForwardedProto, "ws")
+		}
+	}
+
+	if xfPort := req.Header.Get(XForwardedPort); xfPort == "" {
+		req.Header.Set(XForwardedPort, forwardedPort(req))
+	}
+
+	if xfHost := req.Header.Get(XForwardedHost); xfHost == "" && req.Host != "" {
+		req.Header.Set(XForwardedHost, req.Host)
+	}
+
+	if rw.Hostname != "" {
+		req.Header.Set(XForwardedServer, rw.Hostname)
+	}
+}
+
+func forwardedPort(req *http.Request) string {
+	if req == nil {
+		return ""
+	}
+
+	if _, port, err := net.SplitHostPort(req.Host); err == nil && port != "" {
+		return port
+	}
+
+	if req.Header.Get(XForwardedProto) == "https" || req.Header.Get(XForwardedProto) == "wss" {
+		return "443"
+	}
+
+	if req.TLS != nil {
+		return "443"
+	}
+
+	return "80"
+}