From 1d19a7d01960fd8dc00bb3929a1ffaee186470fd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Petr=20P=C3=ADsa=C5=99?= <ppisar@redhat.com>
Date: Tue, 21 Aug 2018 16:02:19 +0200
Subject: [PATCH] Do two-way shutdown in t/sni.t
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TLSv1.3 performs more reading and writing in SSL_accept(). If a client
disconnects after the handshake but before the server finishes
SSL_accept(), the t/sni.t test would fail because accept() could fail with
ECONNRESET. This happened randomly.

Failed accept() lead to undef->get_servername() call that triggered
a run-time exception and that caused a client being stucked and the
test script never exited.

This fixes both these issues.

Signed-off-by: Petr Písař <ppisar@redhat.com>
---
 t/sni.t | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/t/sni.t b/t/sni.t
index de0f06e..91206de 100644
--- a/t/sni.t
+++ b/t/sni.t
@@ -68,15 +68,31 @@ if ( $pid == 0 ) {
 
 	$client->verify_hostname($host,'http') or print "not ";
 	print "ok # client verify hostname in cert $host\n";
+	# Shutdown TLS properly. Otherwise TLSv1.3 $server->accept() fails with
+	# ECONNRESET when a client disconnects too early.
+	$client->close('SSL_fast_shutdown' => 0);
     }
     exit;
 }
 
+# If the server dies, a client can get stuck in read(2) while Perl interpreter
+# is collecting children status in the die handler using wait4(2).
+$SIG{__DIE__} = sub {
+    STDERR->print("Server died. Killing client with $pid PID.\n");
+    kill(9, $pid);
+};
 for my $host (@tests) {
-    my $csock = $server->accept or print "not ";
-    print "ok # server accept\n";
+    my $csock = $server->accept;
+    if (!$csock) {
+        print "not ok # server accept SSL_ERROR='$SSL_ERROR', errno='$!'";
+    } else {
+        print "ok # server accept\n";
+    }
     my $name = $csock->get_servername;
     print "not " if ! $name or $name ne $host;
     print "ok # server got SNI name $host\n";
+    # Shutdown TLS properly. Otherwise TLSv1.3 $server->accept() fails with
+    # ECONNRESET when a client disconnects too early.
+    $csock->close('SSL_fast_shutdown' => 0);
 }
 wait;
-- 
2.14.4