Add test cases for this -out option check

Reviewed-by: NMatt Caswell <matt@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3709)

test/recipes/15-test_out_option.t

+#! /usr/bin/env perl
+# Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the OpenSSL license (the "License").  You may not use
+# this file except in compliance with the License.  You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+
+use strict;
+use warnings;
+
+use File::Spec;
+use OpenSSL::Test qw/:DEFAULT srctop_file/;
+use OpenSSL::Test::Utils;
+
+setup("test_out_option");
+
+plan skip_all => "'-out' option tests are not available on Windows or VMS"
+    if $^O =~ /^(VMS|MSWin32)$/;
+
+plan tests => 11;
+
+# The following patterns should be tested:
+#
+# path        dirname
+# /usr/       /
+# /           /
+# .           .
+# ..          .
+
+test_illegal_path('/usr/');
+test_illegal_path('/');
+test_illegal_path('.');
+test_illegal_path('..');
+
+# Test for trying to create a file in a non-exist directory
+my @chars = ("A".."Z", "a".."z", "0".."9");
+my $rand_path = $chars[rand @chars] for 1..32;
+$rand_path .= "/test.pem";
+
+test_illegal_path($rand_path);
+test_legal_path('test.pem');
+unlink 'test.pem';
+
+sub test_illegal_path {
+    my ($path) = @_;
+
+    my $start = time();
+    ok(!run(app([ 'openssl', 'genrsa', '-out', $path, '16384'])), "invalid output path: $path");
+    my $end = time();
+    # The above process should exit in 2 seconds if the path is not valid
+    ok($end - $start < 2, "check time consumed");
+}
+
+sub test_legal_path {
+    my ($path) = @_;
+
+    ok(run(app([ 'openssl', 'genrsa', '-out', $path, '2048'])), "valid output path: $path");
+}