作为一个大项目的切线,我试图实现一些代码来扫描打开的端口,以便我最终可以运行一个数据包测试。目前,我只是试图连接到google.com,并且我知道端口80接受连接,所以我已经格式化了我的代码以扫描一系列端口,包括此端口。但是,虽然我可以直接连接到端口80,但扫描器代码似乎通过它。我想知道如果有人有任何想法?Java Port Scanner缺少开放端口
public class PortScanner {
public static void main(String[] args) throws IOException {
Socket socket = new Socket();
String host = "www.google.com";
System.out.println("Attempting to connect to " + host + " at port 80...");
try {
socket.connect(new InetSocketAddress(host, 80), 5000);
System.out.println("Connection Successful.");
}
catch (Exception e) {
//Just bypass the exceptions for now
}
System.out.println("Scanning for open ports on " + host);
for (int i = 75; i < 85; i++) {
System.out.println("Attempting to connect to " + host + " on port " + i);
try {
socket.connect(new InetSocketAddress(host, i), 5000);
System.out.println("Open port found at " + i);
}
catch (ConnectException e) {
System.err.println("Connect Exception Thrown on Port " + i);
continue;
}
catch (SocketException e) {
System.err.println("Socket Exception Thrown on Port " + i);
continue;
}
catch (UnknownHostException e) {
System.err.println("Unknown host at " + host);
System.exit(1);
}
}
System.out.println("Closing connection to " + host);
socket.close();
System.out.println("Connection closed");
}
}
事实上,循环报告说,在80端口抛出SocketException:
Attempting to connect to www.google.com at port 80...
Connection Successful.
Scanning for open ports on www.google.com
Socket Exception Thrown on Port 75
Socket Exception Thrown on Port 76
Socket Exception Thrown on Port 77
Socket Exception Thrown on Port 78
Socket Exception Thrown on Port 79
Socket Exception Thrown on Port 80
Socket Exception Thrown on Port 81
Socket Exception Thrown on Port 82
Socket Exception Thrown on Port 83
Attempting to connect to www.google.com on port 75
Socket Exception Thrown on Port 84
Attempting to connect to www.google.com on port 76
Attempting to connect to www.google.com on port 77
Attempting to connect to www.google.com on port 78
Attempting to connect to www.google.com on port 79
Attempting to connect to www.google.com on port 80
Attempting to connect to www.google.com on port 81
Attempting to connect to www.google.com on port 82
Attempting to connect to www.google.com on port 83
Attempting to connect to www.google.com on port 84
Closing connection to www.google.com
Connection closed
在控制台日志的顺序出来的事实,他们都让我怀疑,如果连接尝试可能会过快,从而导致程序错过可用的端口,但我不确定该怎么做。
任何想法赞赏!
您是否认为Google可能会阻止您,因为您正在对其中一台机器执行未经授权的端口扫描。你应该对自己的套件进行测试,而不是别人的测试。 – 2015-02-10 12:00:21
我没有考虑过这个!在更大的背景下,我试图构建一个ping测试器,我在Java中理解意味着您需要套接字连接。如果您不知道要连接哪个端口,并且无法扫描端口,那么还有什么其他选项? – lordchancellor 2015-02-10 12:04:36
可能没有其他选择。但谷歌会公开他们提供的服务,因此会阻止试图寻找其他内容的客户。 测试服务的存在已经做了很多工作,但没有触发检测系统。这在某种程度上是一种猫和老鼠的游戏。你可能会考虑研究像nmap这样的工具。 – 2015-02-10 12:07:27