woodpecker/router/middleware/location/location.go
Tanguy Herrmann 4fde58d57e Adds RFC7239 checks to the new location middleware.
The RFC7239 is the standard way to define headers about reverse proxy
redirections. It replaces all the X-Forwarded-* previous way of defining them.
We let the previous implementations exist to avoid breaking existant installations.
2015-12-03 18:36:55 +01:00

95 lines
2.7 KiB
Go

package location
import (
"net/http"
"strings"
"github.com/gin-gonic/gin"
)
// Resolve is a middleware function that resolves the hostname
// and scheme for the http.Request and adds to the context.
func Resolve(c *gin.Context) {
c.Set("host", resolveHost(c.Request))
c.Set("scheme", resolveScheme(c.Request))
c.Next()
}
// parseHeader parses non unique headers value
// from a http.Request and return a slice of the values
// queried from the header
func parseHeader(r *http.Request, header string, token string) (val []string) {
for _, v := range r.Header[header] {
options := strings.Split(v, ";")
for _, o := range options {
keyvalue := strings.Split(o, "=")
var key, value string
if len(keyvalue) > 1 {
key, value = strings.TrimSpace(keyvalue[0]), strings.TrimSpace(keyvalue[1])
}
key = strings.ToLower(key)
if key == token {
val = append(val, value)
}
}
}
return
}
// resolveScheme is a helper function that evaluates the http.Request
// and returns the scheme, HTTP or HTTPS. It is able to detect,
// using the X-Forwarded-Proto, if the original request was HTTPS
// and routed through a reverse proxy with SSL termination.
func resolveScheme(r *http.Request) string {
switch {
case r.URL.Scheme == "https":
return "https"
case r.TLS != nil:
return "https"
case strings.HasPrefix(r.Proto, "HTTPS"):
return "https"
case r.Header.Get("X-Forwarded-Proto") == "https":
return "https"
case len(r.Header.Get("Forwarded")) != 0 && len(parseHeader(r, "Forwarded", "proto")) != 0 && parseHeader(r, "Forwarded", "proto")[0] == "https":
return "https"
default:
return "http"
}
}
// resolveHost is a helper function that evaluates the http.Request
// and returns the hostname. It is able to detect, using the
// X-Forarded-For header, the original hostname when routed
// through a reverse proxy.
func resolveHost(r *http.Request) string {
switch {
case len(r.Host) != 0:
return r.Host
case len(r.URL.Host) != 0:
return r.URL.Host
case len(r.Header.Get("X-Forwarded-For")) != 0:
return r.Header.Get("X-Forwarded-For")
case len(r.Header.Get("Forwarded")) != 0 && len(parseHeader(r, "Forwarded", "for")) != 0:
return parseHeader(r, "Forwarded", "for")[0]
case len(r.Header.Get("X-Host")) != 0:
return r.Header.Get("X-Host")
case len(r.Header.Get("Forwarded")) != 0 && len(parseHeader(r, "Forwarded", "host")) != 0:
return parseHeader(r, "Forwarded", "host")[0]
case len(r.Header.Get("XFF")) != 0:
return r.Header.Get("XFF")
case len(r.Header.Get("X-Real-IP")) != 0:
return r.Header.Get("X-Real-IP")
default:
return "localhost:8000"
}
}
// Hostname returns the hostname associated with
// the current context.
func Hostname(c *gin.Context) (host string) {
v, ok := c.Get("host")
if ok {
host = v.(string)
}
return
}