没有身份验证的java安全套接字？

Question

我有一个简单的安全套接字服务器-客户端程序。
对于服务器证书，我使用 keytool 创建了一个 keystore 。
当我尝试通过我的客户端连接到服务器时，出现以下异常:
在服务器中:

Exception in thread "main" javax.net.ssl.SSLHandshakeException: Received fatal alert: certificate_unknown

在客户端:

Exception in thread "main" javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Unknown Source)

如果我的理解是正确的，这些异常是由于我正在使用我创建的证书这一事实造成的。
我的问题如下:
如果我在服务器和客户端中设置启用的密码套件，所有 *_anon* 密码套件，这不应该解决问题吗？
我的意思是，如果我启用 *_anon_* 密码套件，则不需要身份验证，因此没有异常(exception)。
这是正确的吗？
因为我仍然有异常(exception)。我尝试在启用的密码套件中使用所有启用的+_anon 的密码套件。没有成功。我尝试只设置匿名的并得到一个新的异常:

Exception in thread "main" java.lang.IllegalArgumentException: Name must not be null

有人可以用匿名密码套件解释为什么我会得到这些异常吗？
注意:
如果我在客户端上设置系统属性 javax.net.ssl.trustStore 指向我创建并被我的服务器使用的 keystore ，则通信正常!
该程序无一异常(exception)地工作，并且数据从客户端到服务器发送正常。

---

更新:
这是我用来启用匿名密码的片段(我已经为服务器和客户端部分做了这个):

String[] supported = server.getSupportedCipherSuites();
String[] anonCipherSuitesSupported = new String[supported.length];
int count = 0;

for(int i = 0; i < supported.length; i++)
{
    if(supported[i].indexOf("_anon_") > 0)
    {
        anonCipherSuitesSupported[count++] = supported[i];
    }
}

String[] oldEnabled = server.getEnabledCipherSuites();
String[] newEnabled = new String[oldEnabled.length + count];
System.arraycopy(oldEnabled, 0, newEnabled, 0, oldEnabled.length);
System.arraycopy(anonCipherSuitesSupported, 0, newEnabled, oldEnabled.length, count);
server.setEnabledCipherSuites(newEnabled);

堆栈跟踪在客户端:

Exception in thread "main" javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.fatal(Unknown Source)
    at com.sun.net.ssl.internal.ssl.Handshaker.fatalSE(Unknown Source)
    at com.sun.net.ssl.internal.ssl.Handshaker.fatalSE(Unknown Source)
    at com.sun.net.ssl.internal.ssl.ClientHandshaker.serverCertificate(Unknown Source)
    at com.sun.net.ssl.internal.ssl.ClientHandshaker.processMessage(Unknown Source)
    at com.sun.net.ssl.internal.ssl.Handshaker.processLoop(Unknown Source)
    at com.sun.net.ssl.internal.ssl.Handshaker.process_record(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.writeRecord(Unknown Source)
    at com.sun.net.ssl.internal.ssl.AppOutputStream.write(Unknown Source)
    at sun.nio.cs.StreamEncoder.writeBytes(Unknown Source)
    at sun.nio.cs.StreamEncoder.implFlushBuffer(Unknown Source)
    at sun.nio.cs.StreamEncoder.implFlush(Unknown Source)
    at sun.nio.cs.StreamEncoder.flush(Unknown Source)
    at java.io.OutputStreamWriter.flush(Unknown Source)
    at com.client.SSLClient1.main(SSLClient1.java:58)
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at sun.security.validator.PKIXValidator.doBuild(Unknown Source)
    at sun.security.validator.PKIXValidator.engineValidate(Unknown Source)
    at sun.security.validator.Validator.validate(Unknown Source)
    at com.sun.net.ssl.internal.ssl.X509TrustManagerImpl.validate(Unknown Source)
    at com.sun.net.ssl.internal.ssl.X509TrustManagerImpl.checkServerTrusted(Unknown Source)
    at com.sun.net.ssl.internal.ssl.X509TrustManagerImpl.checkServerTrusted(Unknown Source)
    ... 14 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(Unknown Source)
    at java.security.cert.CertPathBuilder.build(Unknown Source)
    ... 20 more

在服务器端:

Exception in thread "main" javax.net.ssl.SSLHandshakeException: Received fatal alert: certificate_unknown
    at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Unknown Source)
    at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.recvAlert(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readDataRecord(Unknown Source)
    at com.sun.net.ssl.internal.ssl.AppInputStream.read(Unknown Source)
    at com.sun.net.ssl.internal.ssl.AppInputStream.read(Unknown Source)
    at com.server.SecureOrderTaker.main(SecureOrderTaker.java:92) 

现在如果我简单地做:

server.setEnabledCipherSuites(anonCipherSuitesSupported);

因此仅启用匿名密码套件我得到:

Exception in thread "main" java.lang.IllegalArgumentException: Name must not be null
    at com.sun.net.ssl.internal.ssl.CipherSuite.valueOf(Unknown Source)
    at com.sun.net.ssl.internal.ssl.CipherSuiteList.<init>(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLServerSocketImpl.setEnabledCipherSuites(Unknown Source)
    at com.server.SecureOrderTaker.main(SecureOrderTaker.java:82)

谢谢

Answer 1

你是对的，*_anon_* 密码用于完全未经身份验证的连接(服务器和客户端都是匿名的)。使用这些密码套件不需要证书。我写了一个小代码来测试:

ServerSocketFactory sf = SSLServerSocketFactory.getDefault();
final SSLServerSocket socket = (SSLServerSocket)sf.createServerSocket(443);
System.out.println(Arrays.toString(socket.getSupportedCipherSuites()));
System.out.println(Arrays.toString(socket.getEnabledCipherSuites()));

socket.setEnabledCipherSuites(new String[] {"SSL_DH_anon_EXPORT_WITH_DES40_CBC_SHA"});

Thread t = new Thread() {
    public void run() {
        try {
            Socket client = socket.accept();
            client.getOutputStream().write("Hello World\n".getBytes("ASCII"));
            client.close();
        } catch (IOException ioe) {
        }
    }
};

t.start();
Thread.sleep(2000);
SSLSocket client = (SSLSocket) SSLSocketFactory.getDefault().createSocket("localhost", 443);
client.setEnabledCipherSuites(new String[] {"SSL_DH_anon_EXPORT_WITH_DES40_CBC_SHA"});
InputStream in = client.getInputStream();
byte[] data = new byte[1024];
int len = in.read(data);
System.out.println(new String(data, 0, len));

我知道这段代码并不完美，但我成功地在客户端和服务器之间交换了数据。也许您的服务器或客户端套接字配置不正确。你能提供你得到的完整堆栈跟踪吗？

请注意，这些密码已被弃用，因为它们容易受到中间人攻击。

更新:我发现了问题。 anonCipherSuitesSupported 数组长度太长。因此，在添加 *_anon_* 之后，数组以一堆 null 值结尾。并且实现似乎不接受启用的密码列表中的 null。

String[] supported = server.getSupportedCipherSuites();
List<String> list= new ArrayList<String>();

for(int i = 0; i < supported.length; i++)
{
    if(supported[i].indexOf("_anon_") > 0)
    {
        list.add(supported[i]);
    }
}
String[] anonCipherSuitesSupported = list.toArray(new String[0]);