针对Java中的CA验证X.509证书

Question

可以说我有这样的东西（客户端代码）：

TrustManager[] trustAllCerts = new TrustManager[]{
    new X509TrustManager() {

        @Override
        public java.security.cert.X509Certificate[] getAcceptedIssuers() {
            return null;
        }

        @Override
        public void checkClientTrusted(
                java.security.cert.X509Certificate[] certs, String authType) {
        }

        @Override
        public void checkServerTrusted(
                java.security.cert.X509Certificate[] certs, String authType) {
        }
    }
};

SSLContext sslc = SSLContext.getInstance("TLS");
sslc.init(null, trustAllCerts, null);

SocketFactory sf = sslc.getSocketFactory();
SSLSocket s = (SSLSocket) sf.createSocket("127.0.0.1", 9124);

这段代码是完整的功能，但是我真的不知道如何根据pem文件中可用的一个具体的CA证书来验证服务器的证书。

所有证书均由我的自签名CA签名，这是我需要根据其进行验证的CA（仅针对此证书）。

每个答案表示赞赏。

编辑：

回应 jglouie （非常感谢您-无法投票支持您的答案）。

我创建了解决方案：

new X509TrustManager() {

        @Override
        public java.security.cert.X509Certificate[] getAcceptedIssuers() {
            return null;
        }

        @Override
        public void checkClientTrusted(
                java.security.cert.X509Certificate[] certs, String authType) {
        }

        @Override
        public void checkServerTrusted(
                java.security.cert.X509Certificate[] certs, String authType)
                throws CertificateException {
            InputStream inStream = null;
            try {
                // Loading the CA cert
                URL u = getClass().getResource("tcp/cacert.pem");
                inStream = new FileInputStream(u.getFile());
                CertificateFactory cf = CertificateFactory.getInstance("X.509");
                X509Certificate ca = (X509Certificate) cf.generateCertificate(inStream);
                inStream.close();

                for (X509Certificate cert : certs) {
                    // Verifing by public key
                    cert.verify(ca.getPublicKey());
                }
            } catch (Exception ex) {
                Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null, ex);
            } finally {
                try {
                    inStream.close();
                } catch (IOException ex) {
                    Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null, ex);
                }
            }

        }
    }
};

Answer 1

我假设您的CA的自签名证书已按以下方式加载：

CertificateFactory cf = CertificateFactory.getInstance("X.509");   
FileInputStream finStream = new FileInputStream("CACertificate.pem"); 
X509Certificate caCertificate = (X509Certificate)cf.generateCertificate(finStream);

然后在检查证书的方法中：

@Override        
 public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType)  throws CertificateException {

 if (certs == null || certs.length == 0) {  
      throw new IllegalArgumentException("null or zero-length certificate chain");  
 }

 if (authType == null || authType.length() == 0) {  
            throw new IllegalArgumentException("null or zero-length authentication type");  
  }

   //Check if certificate send is your CA's
    if(!certs[0].equals(caCertificate)){
         try
         {   //Not your CA's. Check if it has been signed by your CA
             certs[0].verify(caCertificate.getPublicKey())
         }
         catch(Exception e){   
              throw new CertificateException("Certificate not trusted",e);
         }
    }
    //If we end here certificate is trusted. Check if it has expired.  
     try{
          certs[0].checkValidity();
      }
      catch(Exception e){
            throw new CertificateException("Certificate not trusted. It has expired",e);
      }  
}

免责声明： 甚至没有尝试编译代码