Question

以下是我用来扫描端口的代码，如果它是打开的。

https://stackoverflow.com/a/8957053/2203703

有人可以试着解决它吗？它似乎无法正常工作，即使端口关闭，代码也始终返回“已成功连接”

这是我用端口80测试它的ip列表

79.142.126.3 //Connection refused 
222.165.195.103 //Connection refused
64.75.193.162 //Connection refused
118.97.197.146 //Port is open
222.134.154.103 //Connection timed out 
173.0.59.170 //Port is open

这是输出：

5 sockets connected successfully
79.142.126.3 connected successfully
222.165.195.103 connected successfully
64.75.193.162 connected successfully
118.97.197.146 connected successfully
173.0.59.170 connected successfully

代码看起来很好，但我真的找不到问题。

请帮忙吗？

Answer 1

您链接的代码是很久以前编写的，当时我对非阻塞I / O的许多方面的理解有限。

真的这需要一个事件循环，其中有很多实现，但是对于这个例子，我将使用@rdlowrey的Alert库，因为它是一个非常简单的极简主义代码了解。您还可以在React进行循环，这是更高级别并提供更多功能。

请注意，以下示例需要PHP 5.4 +

<?php

// Array of addresses to test
$addresses = [
    '192.168.5.150',
    '192.168.5.152',
    'google.com',    // Important note: DNS is resolved synchronously here.
    '192.168.5.155', // this can seriously slow down the process as it can block
    '192.168.5.20',  // for a few seconds, async DNS resolution is non-trivial
    '192.168.40.40', // though
];
// The TCP port to test
$port = 80;
// The length of time in seconds to allow host to respond
$timeout = 5;

// This will hold the results
$lookups = [];

// Create a reactor
$reactor = (new \Alert\ReactorFactory)->select();

$count = count($addresses);
$completedCount = 0;

$onComplete = function($address, $result)
                  use(&$lookups, &$completedCount, $count, $reactor) {

    // Cancel the watchers for this address
    $reactor->cancel($lookups[$address]['failWatcher']);
    $reactor->cancel($lookups[$address]['writeWatcher']);
    $reactor->cancel($lookups[$address]['readWatcher']);

    // Store the result
    $lookups[$address] = $result;

    // If there's nothing left to do, stop the reactor
    if (++$completedCount == $count) {
        $reactor->stop();
    }
};

foreach ($addresses as $address) {
    // Normalise the address to lower-case, as it will be used as an array key
    $address = strtolower($address);

    if (!isset($lookups[$address])) {
        // Create a socket to connect asynchronously
        $sockAddr = "tcp://{$address}:{$port}";
        $flags = STREAM_CLIENT_ASYNC_CONNECT;
        $socket = stream_socket_client($sockAddr, $errNo, $errStr, 0, $flags);
        stream_set_blocking($socket, 0);

        // Set up a timeout to watch for failed connections
        $failWatcher = function() use($address, $onComplete, $timeout) {
            echo "{$address} connect failed: Connect timed out\n";
            $onComplete($address, false);
        };
        $failWatcherId = $reactor->once($failWatcher, $timeout);

        // Watch for the stream becoming writable (connection success)
        $writeWatcher = function() use($address, $onComplete) {
            echo "{$address} connected successfully\n";
            $onComplete($address, true);
        };
        $writeWatcherId = $reactor->onWritable($socket, $writeWatcher);

        // Watch for the stream becoming readable (success or explicit fail)
        $readWatcher = function() use($address, $onComplete, $socket) {
            if ('' === $data = fread($socket, 1024)) {
                echo "{$address} connect failed: Server refused connection\n";
                $onComplete($address, false);
            } else if ($data === false) {
                echo "{$address} connect failed: Stream read error\n";
                $onComplete($address, false);
            } else {
                echo "{$address} connected successfully\n";
                $onComplete($address, true);
            }
        };
        $readWatcherId = $reactor->onReadable($socket, $readWatcher);

        // Store the watcher IDs so they can be destroyed later
        $lookups[$address] = [
            'failWatcher'  => $failWatcherId,
            'writeWatcher' => $writeWatcherId,
            'readWatcher'  => $readWatcherId,
        ];
    }
}

// Set everything going
$reactor->run();

// $lookups is now an array of booleans indicating whether the address resulted
// in a successful connection

Answer 2

此代码打印出“成功”，无论如何也会失败..

您可以看到echo "$count sockets connected successfully\n"和echo "$address connected successfully\n"不依赖于任何条件......

只有echo "Created socket for $address\n"取决于条件，但是当端口关闭时也可以创建套接字。

我没有看到任何问题。将打印“X套接字连接成功”的常规消息（您可以将其删除...）但不会打印特定消息“XXXXX已成功连接”！

Answer 3

如果你能负担得起顺序测试ips（显然，然后并行测试速度慢），那么你可以简化代码并从socket_connect函数中获得有用的响应：

<?php

  // An array of hosts to check
  $addresses = array(
    '79.142.126.3', //Connection refused
    '222.165.195.103', //Connection refused
    '64.75.193.162', //Connection refused
    '118.97.197.146', //Port is open
    '222.134.154.103', //Connection timed out
    '173.0.59.170' //Port is open
  );

  // The TCP port to test
  $testport = 80;
  // The length of time in seconds to allow host to respond
  $timeout = 5;

  foreach ($addresses as $address) {

    if (!$sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP)) {
      echo "Could not create socket for $address\n";
      continue;
    }

    socket_set_option($sock, SOL_SOCKET, SO_RCVTIMEO, array('sec' => $timeout, 'usec' => 0));
    socket_set_option($sock, SOL_SOCKET, SO_SNDTIMEO, array('sec' => $timeout, 'usec' => 0));

    if (@socket_connect($sock, $address, $testport)) {
        echo "$address connected successfully\n";
    }
    else {
        echo "Unable to connect to $address\n";
    }
  }

响应：

Unable to conenct to 79.142.126.3
Unable to conenct to 222.165.195.103
Unable to conenct to 64.75.193.162
118.97.197.146 connected successfully
Unable to conenct to 222.134.154.103
173.0.59.170 connected successfully

TCP连接使用套接字返回false结果

3 个答案: