[master] de11d7d9e h2: Relax "no //" URLs requirement

[Nils Goroll]

commit de11d7d9e898a5668d3d5dc9e7eb55fc826b40da
Author: Dag Haavi Finstad <daghf at varnish-software.com>
Date:   Mon Apr 3 10:26:51 2023 +0200

    h2: Relax "no //" URLs requirement
    
    This requirement was dropped in the updated rfc 9113.
    
    Fixes: #3911

diff --git a/bin/varnishd/http2/cache_http2_hpack.c b/bin/varnishd/http2/cache_http2_hpack.c
index 36570a751..8384856dd 100644
--- a/bin/varnishd/http2/cache_http2_hpack.c
+++ b/bin/varnishd/http2/cache_http2_hpack.c
@@ -135,10 +135,9 @@ h2h_addhdr(struct http *hp, char *b, size_t namelen, size_t len)
 			n = HTTP_HDR_URL;
 			disallow_empty = 1;
 
-			// rfc7540,l,3060,3071
-			if (((len > 0 && *b != '/') ||
-			    (len > 1 && *(b+1) == '/')) &&
-			    (strncmp(b, "*", len) != 0)) {
+			// rfc9113,l,2693,2705
+			if (len > 0 && *b != '/' &&
+			    strncmp(b, "*", len) != 0) {
 				VSLb(hp->vsl, SLT_BogoHeader,
 				    "Illegal :path pseudo-header %.*s",
 				    (int)len, b);
diff --git a/bin/varnishtest/tests/a02027.vtc b/bin/varnishtest/tests/a02027.vtc
index ff34b0071..e9dcf6619 100644
--- a/bin/varnishtest/tests/a02027.vtc
+++ b/bin/varnishtest/tests/a02027.vtc
@@ -22,8 +22,8 @@ client c1 {
 client c1 {
 	stream 1 {
 		txreq -noadd -hdr ":authority" "foo.com" -hdr ":path" "//foo" -hdr ":scheme" "http" -hdr ":method" "GET"
-		rxrst
-		expect rst.err == PROTOCOL_ERROR
+		rxresp
+		expect resp.status == 200
 	} -run
 
 } -run