traefik/vendor/github.com/vulcand/oxy/forward/rewrite.go
2018-08-20 10:38:03 +02:00

98 lines
2.4 KiB
Go

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"
}