diff --git a/stream_ssl_preread_protocol.t b/stream_ssl_preread_protocol.t
new file mode 100644
index 0000000..be27970
--- /dev/null
+++ b/stream_ssl_preread_protocol.t
@@ -0,0 +1,101 @@
+#!/usr/bin/perl
+
+# (C) Sergey Kandaurov
+# (C) Nginx, Inc.
+
+# Tests for stream_ssl_preread module, protocol preread.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+my $t = Test::Nginx->new()->has(qw/stream stream_ssl_preread stream_return/)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+stream {
+    server {
+        listen       127.0.0.1:8080;
+        ssl_preread  on;
+        return       $ssl_preread_protocol;
+    }
+}
+
+EOF
+
+$t->try_run('no ssl_preread_protocol')->plan(6);
+
+###############################################################################
+
+is(get('SSLv3'), 'SSLv3', 'client hello SSLv3');
+is(get('TLSv1'), 'TLSv1', 'client hello TLSv1');
+is(get('TLSv1.1'), 'TLSv1.1', 'client hello TLSv1.1');
+is(get('TLSv1.2'), 'TLSv1.2', 'client hello TLSv1.2');
+
+is(get_tls13(), 'TLSv1.3', 'client hello supported_versions');
+
+TODO: {
+local $TODO = 'not yet';
+
+is(get_ssl2(), 'SSLv2', 'client hello version 2');
+
+}
+
+###############################################################################
+
+sub get {
+	my $v = shift;
+	my ($re, $ch);
+
+	$re = 0x0300, $ch = 0x0300 if $v eq 'SSLv3';
+	$re = 0x0301, $ch = 0x0301 if $v eq 'TLSv1';
+	$re = 0x0301, $ch = 0x0302 if $v eq 'TLSv1.1';
+	$re = 0x0301, $ch = 0x0303 if $v eq 'TLSv1.2';
+
+	my $r = pack("CnNn2C", 0x16, $re, 0x00380100, 0x0034, $ch, 0xeb);
+	$r .= pack("N*", 0x6357cdba, 0xa6b8d853, 0xf1f6ac0f);
+	$r .= pack("N*", 0xdf03178c, 0x0ae41824, 0xe7643682);
+	$r .= pack("N*", 0x3c1b273f, 0xbfde4b00, 0x00000000);
+	$r .= pack("CN3", 0x0c, 0x00000008, 0x00060000, 0x03666f6f);
+
+	http($r);
+}
+
+sub get_tls13 {
+	my $r = pack("N*", 0x16030100, 0x33010000, 0x2f0303eb);
+	$r .= pack("N*", 0x6357cdba, 0xa6b8d853, 0xf1f6ac0f);
+	$r .= pack("N*", 0xdf03178c, 0x0ae41824, 0xe7643682);
+	$r .= pack("N*", 0x3c1b273f, 0xbfde4b00, 0x00000000);
+	$r .= pack("CNCn", 0x07, 0x002b0007, 0x02, 0x7f1c);
+
+	http($r);
+}
+
+sub get_ssl2 {
+	my $r = pack("nCn4", 0x801c, 0x01, 0x0002, 0x0003, 0x0000, 0x0010);
+	$r .= pack("C3", 0x01, 0x00, 0x80);
+	$r .= pack("N4", 0x322dd95c, 0x4749ef17, 0x3d5f0916, 0xf0b730f8);
+
+	http($r);
+}
+
+###############################################################################