From a02ecb0f88cb1c290c0cf940431aff8a6e1891ed Mon Sep 17 00:00:00 2001
From: Matt Holt <mholt@users.noreply.github.com>
Date: Sat, 13 May 2023 07:09:20 -0600
Subject: [PATCH] caddytls: Check for nil ALPN; close #5470 (#5473)

* Check for nil ALPN; close #5470

* Apply patch

* Actually I want to try this
---
 modules/caddytls/connpolicy.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/modules/caddytls/connpolicy.go b/modules/caddytls/connpolicy.go
index 46a8eda3..a4dc4119 100644
--- a/modules/caddytls/connpolicy.go
+++ b/modules/caddytls/connpolicy.go
@@ -54,7 +54,7 @@ func (cp ConnectionPolicies) Provision(ctx caddy.Context) error {
 		}
 
 		// enable HTTP/2 by default
-		if len(pol.ALPN) == 0 {
+		if pol.ALPN == nil {
 			pol.ALPN = append(pol.ALPN, defaultALPN...)
 		}
 
@@ -283,7 +283,7 @@ func (p *ConnectionPolicy) buildStandardTLSConfig(ctx caddy.Context) error {
 			break
 		}
 	}
-	if !alpnFound {
+	if !alpnFound && (cfg.NextProtos == nil || len(cfg.NextProtos) > 0) {
 		cfg.NextProtos = append(cfg.NextProtos, acmez.ACMETLS1Protocol)
 	}