From dcb6e896b8a94ff2d039d67cf3ea766456962da6 Mon Sep 17 00:00:00 2001
From: Vadim Zhestikov <v.zhestikov@f5.com>
Date: Tue, 12 May 2026 09:12:45 -0700
Subject: [PATCH] Tests: add UDP upstream write test for PROXY protocol v2.

---
 t/stream_proxy_protocol_v2_udp.t | 123 +++++++++++++++++++++++++++++++
 1 file changed, 123 insertions(+)
 create mode 100644 t/stream_proxy_protocol_v2_udp.t

diff --git a/t/stream_proxy_protocol_v2_udp.t b/t/stream_proxy_protocol_v2_udp.t
new file mode 100644
index 000000000..9cba8505d
--- /dev/null
+++ b/t/stream_proxy_protocol_v2_udp.t
@@ -0,0 +1,123 @@
+#!/usr/bin/perl
+
+# (C) Nginx, Inc.
+
+# Tests for PROXY protocol v2 write to UDP upstream in stream proxy.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+use IO::Select;
+use Socket qw/ inet_aton /;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+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 bytes.  IPv4 address block: 12 bytes.  Total: 28 bytes.
+my $PPV2_HDR = 28;
+
+# Prime the port cache with TCP locks before write_file_expand processes
+# 127.0.0.1:8080 and 127.0.0.1:8081 via its auto-substitution regex.
+# The default port() holds a UDP lock which would conflict with nginx's
+# "listen udp" directive and the daemon's UDP socket.
+port(8080, udp => 1);
+port(8081, udp => 1);
+
+my $t = Test::Nginx->new()->has(qw/stream/)->plan(9)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+stream {
+    %%TEST_GLOBALS_STREAM%%
+
+    server {
+        listen          127.0.0.1:8080 udp;
+        proxy_pass      127.0.0.1:8081;
+        proxy_protocol  on;
+        proxy_protocol_version 2;
+    }
+}
+
+EOF
+
+$t->run_daemon(\&udp_daemon, port(8081));
+$t->run();
+
+###############################################################################
+
+my $dp = port(8080);
+
+my $s = IO::Socket::INET->new(
+	Proto    => 'udp',
+	PeerAddr => "127.0.0.1:$dp",
+) or die "Can't create UDP socket: $!\n";
+
+$s->send('hello') or die "send: $!\n";
+
+my $data = '';
+my $sel  = IO::Select->new($s);
+if ($sel->can_read(5)) {
+	$s->recv($data, 65536);
+}
+
+my $sp = $s->sockport();
+
+is(substr($data, 0, 12), $SIG,                          'udp v2 signature');
+is(unpack('C', substr($data, 12, 1)), 0x21,              'udp v2 version and command');
+is(unpack('C', substr($data, 13, 1)), 0x12,              'udp v2 AF_INET DGRAM');
+is(unpack('n', substr($data, 14, 2)), 12,                'udp v2 addr block length');
+is(substr($data, 16, 4), inet_aton('127.0.0.1'),         'udp v2 src addr');
+is(substr($data, 20, 4), inet_aton('127.0.0.1'),         'udp v2 dst addr');
+is(unpack('n', substr($data, 24, 2)), $sp,               'udp v2 src port');
+is(unpack('n', substr($data, 26, 2)), $dp,               'udp v2 dst port');
+is(substr($data, $PPV2_HDR), 'hello',                    'udp v2 payload after header');
+
+###############################################################################
+
+sub udp_daemon {
+	my ($port) = @_;
+
+	my $server = IO::Socket::INET->new(
+		Proto     => 'udp',
+		LocalAddr => "127.0.0.1:$port",
+		Reuse     => 1,
+	) or die "Can't create listening UDP socket: $!\n";
+
+	while (1) {
+		my $buf  = '';
+		my $peer = $server->recv($buf, 65536);
+		next unless defined $peer;
+
+		log2i("recv " . length($buf) . " bytes");
+
+		$server->send($buf, 0, $peer);
+
+		log2o("sent " . length($buf) . " bytes");
+	}
+}
+
+sub log2i { Test::Nginx::log_core('|| <<', @_); }
+sub log2o { Test::Nginx::log_core('|| >>', @_); }
+sub log2c { Test::Nginx::log_core('||',    @_); }
+
+###############################################################################