在Servlet中读取客户端证书

Question

我在JBOSS和浏览器客户端中有一个客户端服务器通信方案（JAVA程序）。最初在建立连接时，客户端将其证书发送到服务器。服务器从证书中提取客户端的公钥，因此通信将继续。
现在我的问题是
如何将证书（.cer）从客户端发送到服务器？
如何接收证书并在服务器中提取其公钥？

Answer 1

如何将证书（.cer）从客户端发送到服务器？

首先应将客户端证书（.cer，.crt，.pem）及其相应的私钥（.key）打包到PKCS＃12（.p12，.pfx）或JKS（.jks）容器中（keystore ）。您还应该将服务器的CA证书打包为JKS（信任库）。

示例使用HttpClient 3.x：

HttpClient client = new HttpClient(); 
// truststore 
KeyStore trustStore = KeyStore.getInstance("JKS", "SUN"); 
trustStore.load(TestSupertype.class.getResourceAsStream("/client-truststore.jks"), "amber%".toCharArray()); 
String alg = KeyManagerFactory.getDefaultAlgorithm(); 
TrustManagerFactory fac = TrustManagerFactory.getInstance(alg); 
fac.init(trustStore); 
// keystore 
KeyStore keystore = KeyStore.getInstance("PKCS12", "SunJSSE"); 
keystore.load(X509Test.class.getResourceAsStream("/etomcat_client.p12"), "etomcat".toCharArray()); 
String keyAlg = KeyManagerFactory.getDefaultAlgorithm(); 
KeyManagerFactory keyFac = KeyManagerFactory.getInstance(keyAlg); 
keyFac.init(keystore, "etomcat".toCharArray()); 
// context 
SSLContext ctx = SSLContext.getInstance("TLS", "SunJSSE"); 
ctx.init(keyFac.getKeyManagers(), fac.getTrustManagers(), new SecureRandom()); 
SslContextedSecureProtocolSocketFactory secureProtocolSocketFactory = new SslContextedSecureProtocolSocketFactory(ctx); 
Protocol.registerProtocol("https", new Protocol("https", (ProtocolSocketFactory) secureProtocolSocketFactory, 8443)); 
// test get 
HttpMethod get = new GetMethod("https://127.0.0.1:8443/etomcat_x509"); 
client.executeMethod(get); 
// get response body and do what you need with it 
byte[] responseBody = get.getResponseBody(); 

您可能会发现工作示例的this project看到X509Test类。

随着HttpClient 4.x配置和语法会稍有不同：

HttpClient httpclient = new DefaultHttpClient(); 
// truststore 
KeyStore ts = KeyStore.getInstance("JKS", "SUN"); 
ts.load(PostService.class.getResourceAsStream("/truststore.jks"), "amber%".toCharArray()); 
// if you remove me, you've got 'javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated' on missing truststore 
if(0 == ts.size()) throw new IOException("Error loading truststore"); 
// tmf 
TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm()); 
tmf.init(ts); 
// keystore 
KeyStore ks = KeyStore.getInstance("PKCS12", "SunJSSE"); 
ks.load(PostService.class.getResourceAsStream("/" + certName), certPwd.toCharArray()); 
// if you remove me, you've got 'javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated' on missing keystore 
if(0 == ks.size()) throw new IOException("Error loading keystore"); 
// kmf 
KeyManagerFactory kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm()); 
kmf.init(ks, certPwd.toCharArray()); 
// SSL 
SSLContext ctx = SSLContext.getInstance("TLS"); 
ctx.init(kmf.getKeyManagers(), tmf.getTrustManagers(), null); 
// socket 
SSLSocketFactory socketFactory = new SSLSocketFactory(ctx, SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER); 
Scheme sch = new Scheme("https", 8443, socketFactory); 
httpclient.getConnectionManager().getSchemeRegistry().register(sch); 
// request 
HttpMethod get = new GetMethod("https://localhost:8443/foo"); 
client.executeMethod(get); 
IOUtils.copy(get.getResponseBodyAsStream(), System.out); 

如何接收证书并提取服务器的公钥呢？

您的服务器必须配置为需要X.509客户端证书身份验证。然后，在SSL握手过程中，servlet容器将接收证书，并根据trustore进行检查，并将其作为请求属性提供给应用程序。 在通常情况下与单一证书，你可以使用servlet的环境中，该方法提取证书：

protected X509Certificate extractCertificate(HttpServletRequest req) { 
    X509Certificate[] certs = (X509Certificate[]) req.getAttribute("javax.servlet.request.X509Certificate"); 
    if (null != certs && certs.length > 0) { 
     return certs[0]; 
    } 
    throw new RuntimeException("No X.509 client certificate found in request"); 
}