Tests: proxy_protocol_tlv directive for PROXY protocol v2.

Test that proxy_protocol_tlv correctly appends TLV records to
the PPv2 header sent upstream.  Three TLVs are configured in
one server block: two with static string values and one with a
variable value ($remote_addr), verifying that complex values
are evaluated per connection.

Checks: PPv2 header signature and fixed fields, the PPv2 len
field reflecting the total addr-block + TLV size, and each
TLV's type, wire-format length, and value bytes.

t/stream_proxy_protocol_v2_tlv.t

@@ -0,0 +1,154 @@
+#!/usr/bin/perl
+
+# (C) Nginx, Inc.
+
+# Tests for proxy_protocol_tlv directive in stream proxy.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+use IO::Select;
+use IO::Socket::INET;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+use Test::Nginx::Stream qw/ stream /;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+# PPv2 magic signature (12 bytes)
+my $SIG = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
+
+# Fixed header 16 + IPv4 addr block 12 = 28
+# TLV1: type(1) + len(2) + "foo"(3)  =  6 bytes  [offset 28]
+# TLV2: type(1) + len(2) + "bar"(3)  =  6 bytes  [offset 34]
+# TLV3: type(1) + len(2) + addr(9)   = 12 bytes  [offset 40]
+# payload at offset 52
+my $PPV2_HDR = 52;
+
+my $t = Test::Nginx->new()->has(qw/stream/)->plan(14)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+stream {
+    %%TEST_GLOBALS_STREAM%%
+
+    server {
+        listen          127.0.0.1:%%PORT_8080%%;
+        proxy_pass      127.0.0.1:%%PORT_8081%%;
+        proxy_protocol  on;
+        proxy_protocol_version 2;
+        proxy_protocol_tlv     0x05 "foo";
+        proxy_protocol_tlv     0x06 "bar";
+        proxy_protocol_tlv     0x07 $remote_addr;
+    }
+}
+
+EOF
+
+$t->run_daemon(\&stream_daemon, port(8081));
+$t->run();
+$t->waitforsocket('127.0.0.1:' . port(8081));
+
+###############################################################################
+
+my $s    = stream('127.0.0.1:' . port(8080));
+my $data = $s->io('hello');
+
+is(substr($data, 0, 12),              $SIG,  'tlv v2 signature');
+is(unpack('C', substr($data, 12, 1)), 0x21,  'tlv v2 version and command');
+is(unpack('C', substr($data, 13, 1)), 0x11,  'tlv v2 AF_INET STREAM');
+
+# header->len: 12-byte addr block + 6 + 6 + 12 bytes of TLVs = 36
+is(unpack('n', substr($data, 14, 2)), 36,    'tlv v2 len includes TLVs');
+
+# TLV1 at offset 28: type 0x05, length 3, value "foo"
+is(unpack('C', substr($data, 28, 1)), 0x05,  'tlv1 type');
+is(unpack('n', substr($data, 29, 2)), 3,     'tlv1 length');
+is(substr($data, 31, 3),              'foo', 'tlv1 value');
+
+# TLV2 at offset 34: type 0x06, length 3, value "bar"
+is(unpack('C', substr($data, 34, 1)), 0x06,  'tlv2 type');
+is(unpack('n', substr($data, 35, 2)), 3,     'tlv2 length');
+is(substr($data, 37, 3),              'bar', 'tlv2 value');
+
+# TLV3 at offset 40: type 0x07, variable $remote_addr = "127.0.0.1" (9 bytes)
+is(unpack('C', substr($data, 40, 1)), 0x07,       'tlv3 type');
+is(unpack('n', substr($data, 41, 2)), 9,           'tlv3 length');
+is(substr($data, 43, 9),              '127.0.0.1', 'tlv3 value (remote_addr)');
+
+is(substr($data, $PPV2_HDR), 'hello', 'payload after TLVs');
+
+###############################################################################
+
+sub stream_daemon {
+	my ($port) = @_;
+
+	my $server = IO::Socket::INET->new(
+		Proto     => 'tcp',
+		LocalAddr => '127.0.0.1:' . $port,
+		Listen    => 5,
+		Reuse     => 1,
+	) or die "Can't create listening socket: $!\n";
+
+	my $sel = IO::Select->new($server);
+
+	local $SIG{PIPE} = 'IGNORE';
+
+	while (my @ready = $sel->can_read) {
+		foreach my $fh (@ready) {
+			if ($server == $fh) {
+				my $new = $fh->accept;
+				$new->autoflush(1);
+				$sel->add($new);
+
+			} elsif (stream_handle_client($fh)) {
+				$sel->remove($fh);
+				$fh->close;
+			}
+		}
+	}
+}
+
+sub stream_handle_client {
+	my ($client) = @_;
+
+	log2c("(new connection $client)");
+
+	my $buffer = '';
+	my $csel   = IO::Select->new($client);
+	while ($csel->can_read(0.5)) {
+		my $n = $client->sysread(my $chunk, 65536);
+		last unless $n;
+		$buffer .= $chunk;
+	}
+
+	log2i("$client recv " . length($buffer) . " bytes");
+
+	$client->syswrite($buffer);
+
+	log2o("$client sent " . length($buffer) . " bytes");
+
+	return 1;
+}
+
+sub log2i { Test::Nginx::log_core('|| <<', @_); }
+sub log2o { Test::Nginx::log_core('|| >>', @_); }
+sub log2c { Test::Nginx::log_core('||',    @_); }
+
+###############################################################################