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) } if !IsWebsocketRequest(req) { // Remove hop-by-hop headers to the backend. Especially important is "Connection" because we want a persistent // connection, regardless of what the client sent to us. utils.RemoveHeaders(req.Header, HopHeaders...) } } 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" }