Attaching Echo instance to multiple ports does not work

[maciej-jezierski]

Hi all, I've done the upgrade from 4.1.15 to 4.2.0. I noticed HTTP redirect to HTTPS is running in a cycle and never happens. Also noticed by my website users.

[aldas]

Could you provide example how your Echo is setup and started? Especially how your HTTP server/listener and HTTPS server/listener are setup with Echo instance.

Can you replicate redirect loop with command line tools? I'm asking this because if you are using javascript in frontend your JS implementation could cause that loop. JS in browser decides to direct user to HTTP and Echo (or whatever loadbalancer Nginx/Apache etc you have in front of echo instance) redirects user back to HTTPS from HTTP

[maciej-jezierski]

I don't have Nginx/Apache upfront with the application at this moment.

Set up:

e := echo.New()
renderer := &Template{
		templates: template.Must(template.New("").Funcs(template.FuncMap{
			"safe": func(s string) template.HTMLAttr {
				return template.HTMLAttr(s)
			},
			"meta": func(s api.Tag) template.HTML {
				return template.HTML("<meta " + s.Key + "=\"" + s.Name + "\"  " + s.Type + "=\"" + s.Content + "\" data-vue-router-controlled />")
			},
		}).ParseGlob("web/dist/*.html")),
	}
	e.Renderer = renderer

	e.Pre(middleware.HTTPSRedirect())
	e.Pre(middleware.HTTPSNonWWWRedirect())

	e.Use(middleware.RemoveTrailingSlashWithConfig(middleware.TrailingSlashConfig{
		RedirectCode: http.StatusMovedPermanently,
	}))
	e.Use(middleware.GzipWithConfig(middleware.GzipConfig{
		Level: 2,
	}))

	e.Use(middleware.Recover())
	e.Use(middleware.SecureWithConfig(middleware.SecureConfig{
		ReferrerPolicy: "no-referrer",
	}))

	e.Use(func(next echo.HandlerFunc) echo.HandlerFunc {
		return func(c echo.Context) error {
			if strings.HasSuffix(c.Request().Host, ".webkomiksy.pl") {
				return c.Redirect(http.StatusMovedPermanently, "https://webkomiksy.pl")
			}
			return next(c)
		}
	})
	go func() {
		e.Logger.Fatal(e.Start(":1321"))
	}()
	e.Logger.Fatal(e.StartTLS(":1323", fullchain.pem", "privkey.pem"))

Also, I use prerouting

sudo iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT --to-port 1321
sudo iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-port 1323

Call with curl -v to my test server. As you can see the call is not redirected (so actually I was wrong with the loop, it just didn't hit redirect or response)

*   Trying XXX..
* TCP_NODELAY set
* Connected to XXX
> GET / HTTP/1.1
> Host: XXX
> User-Agent: curl/7.68.0
> Accept: */*

A sample response from production after downgrade

* TCP_NODELAY set
* Connected to webkomiksy.pl (51.68.137.171) port 80 (#0)
> GET / HTTP/1.1
> Host: webkomiksy.pl
> User-Agent: curl/7.68.0
> Accept: */*
> 
* Mark bundle as not supporting multiuse
< HTTP/1.1 301 Moved Permanently
< Location: https://webkomiksy.pl/
< Date: Sat, 20 Feb 2021 22:34:50 GMT
< Content-Length: 0
< 
* Connection #0 to host webkomiksy.pl left intact

[aldas]

@maciej-jezierski problem here is that you are attaching Echo multiple times to same *http.Server instances with e.Start(":1321") and e.StartTLS( calls using different listeners (sockets). This does not work.

If you want to serve on multiple ports you need to use at least e.StartServer() with 2 different http.Server instances or just even create two echo instances (this is probably easier)

For example:

func TestHTTPS_redirect(t *testing.T) {
	createEcho := func() *echo.Echo {
		e := echo.New()
		e.Pre(middleware.HTTPSRedirect())
		e.Pre(middleware.HTTPSNonWWWRedirect())

		e.Use(middleware.RemoveTrailingSlashWithConfig(middleware.TrailingSlashConfig{
			RedirectCode: http.StatusMovedPermanently,
		}))
		e.Use(middleware.GzipWithConfig(middleware.GzipConfig{
			Level: 2,
		}))

		e.Use(middleware.Recover())
		e.Use(middleware.SecureWithConfig(middleware.SecureConfig{
			ReferrerPolicy: "no-referrer",
		}))

		e.Use(func(next echo.HandlerFunc) echo.HandlerFunc {
			return func(c echo.Context) error {
				if strings.HasSuffix(c.Request().Host, ".webkomiksy.pl") {
					return c.Redirect(http.StatusMovedPermanently, "https://webkomiksy.pl")
				}
				return next(c)
			}
		})
		return e
	}
	
	go func() {
		http := createEcho()
		http.Logger.Fatal(http.Start(":1321"))
	}()
	https := createEcho()
	https.Logger.Fatal(https.StartTLS(":1323", "_fixture/certs/cert.pem", "_fixture/certs/key.pem"))
}

[maciej-jezierski]

Thanks, will test it in the next iteration

[aldas]

Fixed in master with PR #1793. This is now possible without modifications