testssl.sh/t/40_tls13.only.t

#!/usr/bin/env perl

# As the name indicates: Check for TLS 1.3 only hosts. It just runs the protocol section, there
# it checks for TLS 1.2 (disabled) and TLS 1.3 (enabled)

use strict;
use warnings;
use Test::More;
use IO::Socket::INET;
use File::Temp qw( tempdir );
use File::Basename;

use POSIX qw(WNOHANG);


my $port = 1443;
my $temp_dir = tempdir(CLEANUP => 1);
my $server_script = "$temp_dir/start_server.sh";
my $os="$^O";

# Non-intrusive check: is $ip:$port in LISTEN state in our network namespace?
# Reads /proc/net/tcp, so it does NOT consume a connection (unlike a probe).
sub port_listening {
    my ($ip, $port) = @_;
    return undef unless -r '/proc/net/tcp';
    my $hex_port = sprintf("%04X", $port);
    my $hex_ip   = join '', map { sprintf("%02X", $_) } reverse split(/\./, $ip);
    open my $fh, '<', '/proc/net/tcp' or return undef;
    while (<$fh>) {
        next if /^sl/;
        my @f = split;
        return 1 if $f[1] eq "$hex_ip:$hex_port" && $f[3] eq '0A';   # 0A == LISTEN
    }
    close $fh;
    return 0;
}

# Shell script as HEREDOC - aim is reusability
my $shell_code = <<'HEREDOC';
#!/bin/bash
# Configuration
PORT=1443
IP=127.0.0.1
CERT="server.pem"
KEY="server.key"
# This OpenSSL version will support TLS 1.3
OPENSSL=/usr/bin/openssl

if [[ $($OPENSSL version) =~ LibreSSL ]]; then              # MacOS. LibreSSL doesn't know "-naccept"
     if [[ -x /opt/homebrew/bin/openssl.NOPE ]]; then
          OPENSSL=/opt/homebrew/bin/openssl.NOPE            # We hid that during GHA CI checks
     elif [[ -x /opt/homebrew/bin/openssl ]]; then
          OPENSSL=/opt/homebrew/bin/openssl                 # If you intend this to run
     fi
fi

# Force a specific TLS 1.3 cipher suite when needed
# CIPHER_SUITE="TLS_AES_256_GCM_SHA384"

# Generate self-signed cert and key if they don't exist
if [ ! -f "$CERT" ] || [ ! -f "$KEY" ]; then
    echo "Generating self-signed certificate and key..."
    $OPENSSL req -x509 -newkey rsa:2048 -keyout "$KEY" -out "$CERT" -days 42 -nodes -subj "/CN=localhost" -addext "subjectAltName=DNS:localhost,IP:127.0.0.1" >/dev/null
fi

# Start OpenSSL server
echo "Starting server on port $PORT..."
# $OPENSSL s_server -accept "$IP:$PORT" -cert "$CERT" -key "$KEY" -tls1_3 -ciphersuites "$CIPHER_SUITE"
env -u RUNNER_TRACKING_ID $OPENSSL s_server -accept "$IP:$PORT" -cert "$CERT" -key "$KEY" -tls1_3 -ign_eof 2>&1

HEREDOC


# Write the script to the temp directory
open(my $fh, '>', $server_script) or die "Cannot write script: $!";
print $fh $shell_code;
close($fh);

chmod 0755, $server_script;

# Start the server in the background using fork/exec
my $pid = fork();
if ($pid == 0) {
    chdir($temp_dir)                       or exit 1;
    open(STDOUT, '>', "$temp_dir/server.log") or exit 1;
    open(STDERR, '>&', STDOUT)               or exit 1;
    exec($server_script);
    exit 1;
}
elsif ($pid > 0) {
   # Wait for the server to be listening on the port
   my $socket;
   my $ready = 0;
   my $listenip = '127.0.0.1';

   for my $i (1..30) {
       $socket = IO::Socket::INET->new(
           PeerAddr => $listenip,
           PeerPort => $port,
           Proto    => 'tcp',
           Timeout  => 2,
       );

       if ($socket) {
           $ready = 1;
           close($socket);
           last;
       }
       sleep (1);
   }

   ok($ready, "Server is listening on $listenip:$port");

   # ---- DEBUG stuff, taken right before testssl runs ----
   my $reaped = waitpid($pid, WNOHANG);          # 0 => still running
   my $state  = ($reaped == 0) ? 'ALIVE' : "DEAD (waitpid=$reaped)";
   diag("DEBUG pre-testssl: pid=$pid state=$state");

   if  ( $os eq "linux" ){
      my $listening = port_listening($listenip, $port);
      diag("DEBUG pre-testssl: $listenip:$port LISTEN=" . ($listening // 'n/a'));
      diag("DEBUG netns: " . (`readlink /proc/self/ns/net 2>&1`));
      diag("DEBUG cgroup: " . (`cat /proc/self/cgroup 2>&1`));
      diag("DEBUG ss: "     . (`ss -ltnp 2>&1 | grep ":$port " || echo "(no listener)"`));

      diag("DEBUG direct bash connect: " .
        (`timeout 2 bash -c "echo > /dev/tcp/$listenip/$port" 2>&1 && echo OK || echo REFUSED`));
   }
   sleep (2);

   my $log_pre = '';
   if (open my $lfh, '<', "$temp_dir/server.log") {
       local $/;
       $log_pre = <$lfh> // '';
       close $lfh;
   }
   diag("DEBUG pre-testssl server.log:\n$log_pre");
   # ---- end DEBUG ----

   my $testssl_output = `./testssl.sh --protocols $listenip:$port 2>&1`;

   like($testssl_output,   qr/TLS 1\.3/,        "TLS 1.3 is supported");
   unlike($testssl_output, qr/OFFERED\s+TLS 1\.2/, "TLS 1.2 is NOT offered");

   my $log = '';
   if (open my $lfh, '<', "$temp_dir/server.log") {
       local $/;
       $log = <$lfh> // '';
       close $lfh;
   }
#   diag("Server Log:\n$log");
}

# Cleanup: Kill the server process. When running locally this is needed
my $openssl_pid = `lsof -i -Pn | grep \$USER | grep openssl | awk '{ print \$2 }'`;
chomp $openssl_pid;
if ($openssl_pid) { kill 9, $openssl_pid; waitpid($openssl_pid, 0); }

done_testing();

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