Java加密技术（九）——初探SSL

在 Java加密技术（八）中，我们模拟了一个基于RSA非对称加密网络的安全通信。现在我们深度了解一下现有的安全网络通信——SSL。
    我们需要构建一个由CA机构签发的有效证书，这里我们使用上文中生成的自签名证书 zlex.cer
    这里，我们将证书导入到我们的密钥库。

Shell代码  

1. keytool -import -alias www.zlex.org -file d:/zlex.cer -keystore d:/zlex.keystore  

keytool -import -alias www.zlex.org -file d:/zlex.cer -keystore d:/zlex.keystore

其中
-import表示 导入
-alias指定别名，这里是 www.zlex.org
-file指定算法，这里是 d:/zlex.cer
-keystore指定存储位置，这里是 d:/zlex.keystore
在这里我使用的密码为 654321

控制台输出：

Console代码  

1. 输入keystore密码：  
2. 再次输入新密码:  
3. 所有者:CN=www.zlex.org, OU=zlex, O=zlex, L=BJ, ST=BJ, C=CN  
4. 签发人:CN=www.zlex.org, OU=zlex, O=zlex, L=BJ, ST=BJ, C=CN  
5. 序列号:4a1e48df  
6. 有效期: Thu May 28 16:18:39 CST 2009 至Wed Aug 26 16:18:39 CST 2009  
7. 证书指纹:  
8.          MD5:19:CA:E6:36:E2:DF:AD:96:31:97:2F:A9:AD:FC:37:6A  
9.          SHA1:49:88:30:59:29:45:F1:69:CA:97:A9:6D:8A:CF:08:D2:C3:D5:C0:C4  
10.          签名算法名称:SHA1withRSA  
11.          版本: 3  
12. 信任这个认证？ [否]：  y  
13. 认证已添加至keystore中  

输入keystore密码：
再次输入新密码:
所有者:CN=www.zlex.org, OU=zlex, O=zlex, L=BJ, ST=BJ, C=CN
签发人:CN=www.zlex.org, OU=zlex, O=zlex, L=BJ, ST=BJ, C=CN
序列号:4a1e48df
有效期: Thu May 28 16:18:39 CST 2009 至Wed Aug 26 16:18:39 CST 2009
证书指纹:
         MD5:19:CA:E6:36:E2:DF:AD:96:31:97:2F:A9:AD:FC:37:6A
         SHA1:49:88:30:59:29:45:F1:69:CA:97:A9:6D:8A:CF:08:D2:C3:D5:C0:C4
         签名算法名称:SHA1withRSA
         版本: 3
信任这个认证？ [否]：  y
认证已添加至keystore中

OK，最复杂的准备工作已经完成。
接下来我们将域名 www.zlex.org定位到本机上。打开 C:\Windows\System32\drivers\etc\hosts文件，将 www.zlex.org绑定在本机上。在文件末尾追加 127.0.0.1       www.zlex.org。现在通过地址栏访问 http://www.zlex.org，或者通过 ping命令，如果能够定位到本机，域名映射就搞定了。
现在，配置tomcat。先将 zlex.keystore拷贝到tomcat的conf目录下，然后配置 server.xml。将如下内容加入配置文件

Xml代码  

1. <Connector  
2.     SSLEnabled="true"  
3.     URIEncoding="UTF-8"  
4.     clientAuth="false"  
5.     keystoreFile="conf/zlex.keystore"  
6.     keystorePass="123456"  
7.     maxThreads="150"  
8.     port="443"  
9.     protocol="HTTP/1.1"  
10.     scheme="https"  
11.     secure="true"  
12.     sslProtocol="TLS" />  

<Connector
			SSLEnabled="true"
			URIEncoding="UTF-8"
			clientAuth="false"
			keystoreFile="conf/zlex.keystore"
			keystorePass="123456"
			maxThreads="150"
			port="443"
			protocol="HTTP/1.1"
			scheme="https"
			secure="true"
			sslProtocol="TLS" />

注意 clientAuth="false"测试阶段，置为 false，正式使用时建议使用 true。现在启动tomcat，访问 https://www.zlex.org/。
显然，证书未能通过认证，这个时候你可以选择安装证书（上文中的 zlex.cer文件就是证书），作为 受信任的根证书颁发机构导入，再次重启浏览器（IE，其他浏览器对于域名www.zlex.org不支持本地方式访问），访问 https://www.zlex.org/，你会看到地址栏中会有个小锁 ，就说明安装成功。所有的浏览器联网操作已经在RSA加密解密系统的保护之下了。但似乎我们感受不到。
这个时候很多人开始怀疑，如果我们要手工做一个这样的https的访问是不是需要把浏览器的这些个功能都实现呢？不需要！

接着上篇内容，给出如下代码实现：

Java代码  

1. import java.io.FileInputStream;  
2. import java.security.KeyStore;  
3. import java.security.PrivateKey;  
4. import java.security.PublicKey;  
5. import java.security.Signature;  
6. import java.security.cert.Certificate;  
7. import java.security.cert.CertificateFactory;  
8. import java.security.cert.X509Certificate;  
9. import java.util.Date;  
10.   
11. import javax.crypto.Cipher;  
12. import javax.net.ssl.HttpsURLConnection;  
13. import javax.net.ssl.KeyManagerFactory;  
14. import javax.net.ssl.SSLContext;  
15. import javax.net.ssl.SSLSocketFactory;  
16. import javax.net.ssl.TrustManagerFactory;  
17.   
18. /** 
19.  * 证书组件 
20.  *  
21.  * @author 梁栋 
22.  * @version 1.0 
23.  * @since 1.0 
24.  */  
25. public abstract class CertificateCoder extends Coder {  
26.   
27.     /** 
28.      * Java密钥库(Java Key Store，JKS)KEY_STORE 
29.      */  
30.     public static final String KEY_STORE = "JKS";  
31.   
32.     public static final String X509 = "X.509";  
33.     public static final String SunX509 = "SunX509";  
34.     public static final String SSL = "SSL";  
35.   
36.     /** 
37.      * 由KeyStore获得私钥 
38.      *  
39.      * @param keyStorePath 
40.      * @param alias 
41.      * @param password 
42.      * @return 
43.      * @throws Exception 
44.      */  
45.     private static PrivateKey getPrivateKey(String keyStorePath, String alias,  
46.             String password) throws Exception {  
47.         KeyStore ks = getKeyStore(keyStorePath, password);  
48.         PrivateKey key = (PrivateKey) ks.getKey(alias, password.toCharArray());  
49.         return key;  
50.     }  
51.   
52.     /** 
53.      * 由Certificate获得公钥 
54.      *  
55.      * @param certificatePath 
56.      * @return 
57.      * @throws Exception 
58.      */  
59.     private static PublicKey getPublicKey(String certificatePath)  
60.             throws Exception {  
61.         Certificate certificate = getCertificate(certificatePath);  
62.         PublicKey key = certificate.getPublicKey();  
63.         return key;  
64.     }  
65.   
66.     /** 
67.      * 获得Certificate 
68.      *  
69.      * @param certificatePath 
70.      * @return 
71.      * @throws Exception 
72.      */  
73.     private static Certificate getCertificate(String certificatePath)  
74.             throws Exception {  
75.         CertificateFactory certificateFactory = CertificateFactory  
76.                 .getInstance(X509);  
77.         FileInputStream in = new FileInputStream(certificatePath);  
78.   
79.         Certificate certificate = certificateFactory.generateCertificate(in);  
80.         in.close();  
81.   
82.         return certificate;  
83.     }  
84.   
85.     /** 
86.      * 获得Certificate 
87.      *  
88.      * @param keyStorePath 
89.      * @param alias 
90.      * @param password 
91.      * @return 
92.      * @throws Exception 
93.      */  
94.     private static Certificate getCertificate(String keyStorePath,  
95.             String alias, String password) throws Exception {  
96.         KeyStore ks = getKeyStore(keyStorePath, password);  
97.         Certificate certificate = ks.getCertificate(alias);  
98.   
99.         return certificate;  
100.     }  
101.   
102.     /** 
103.      * 获得KeyStore 
104.      *  
105.      * @param keyStorePath 
106.      * @param password 
107.      * @return 
108.      * @throws Exception 
109.      */  
110.     private static KeyStore getKeyStore(String keyStorePath, String password)  
111.             throws Exception {  
112.         FileInputStream is = new FileInputStream(keyStorePath);  
113.         KeyStore ks = KeyStore.getInstance(KEY_STORE);  
114.         ks.load(is, password.toCharArray());  
115.         is.close();  
116.         return ks;  
117.     }  
118.   
119.     /** 
120.      * 私钥加密 
121.      *  
122.      * @param data 
123.      * @param keyStorePath 
124.      * @param alias 
125.      * @param password 
126.      * @return 
127.      * @throws Exception 
128.      */  
129.     public static byte[] encryptByPrivateKey(byte[] data, String keyStorePath,  
130.             String alias, String password) throws Exception {  
131.         // 取得私钥  
132.         PrivateKey privateKey = getPrivateKey(keyStorePath, alias, password);  
133.   
134.         // 对数据加密  
135.         Cipher cipher = Cipher.getInstance(privateKey.getAlgorithm());  
136.         cipher.init(Cipher.ENCRYPT_MODE, privateKey);  
137.   
138.         return cipher.doFinal(data);  
139.   
140.     }  
141.   
142.     /** 
143.      * 私钥解密 
144.      *  
145.      * @param data 
146.      * @param keyStorePath 
147.      * @param alias 
148.      * @param password 
149.      * @return 
150.      * @throws Exception 
151.      */  
152.     public static byte[] decryptByPrivateKey(byte[] data, String keyStorePath,  
153.             String alias, String password) throws Exception {  
154.         // 取得私钥  
155.         PrivateKey privateKey = getPrivateKey(keyStorePath, alias, password);  
156.   
157.         // 对数据加密  
158.         Cipher cipher = Cipher.getInstance(privateKey.getAlgorithm());  
159.         cipher.init(Cipher.DECRYPT_MODE, privateKey);  
160.   
161.         return cipher.doFinal(data);  
162.   
163.     }  
164.   
165.     /** 
166.      * 公钥加密 
167.      *  
168.      * @param data 
169.      * @param certificatePath 
170.      * @return 
171.      * @throws Exception 
172.      */  
173.     public static byte[] encryptByPublicKey(byte[] data, String certificatePath)  
174.             throws Exception {  
175.   
176.         // 取得公钥  
177.         PublicKey publicKey = getPublicKey(certificatePath);  
178.         // 对数据加密  
179.         Cipher cipher = Cipher.getInstance(publicKey.getAlgorithm());  
180.         cipher.init(Cipher.ENCRYPT_MODE, publicKey);  
181.   
182.         return cipher.doFinal(data);  
183.   
184.     }  
185.   
186.     /** 
187.      * 公钥解密 
188.      *  
189.      * @param data 
190.      * @param certificatePath 
191.      * @return 
192.      * @throws Exception 
193.      */  
194.     public static byte[] decryptByPublicKey(byte[] data, String certificatePath)  
195.             throws Exception {  
196.         // 取得公钥  
197.         PublicKey publicKey = getPublicKey(certificatePath);  
198.   
199.         // 对数据加密  
200.         Cipher cipher = Cipher.getInstance(publicKey.getAlgorithm());  
201.         cipher.init(Cipher.DECRYPT_MODE, publicKey);  
202.   
203.         return cipher.doFinal(data);  
204.   
205.     }  
206.   
207.     /** 
208.      * 验证Certificate 
209.      *  
210.      * @param certificatePath 
211.      * @return 
212.      */  
213.     public static boolean verifyCertificate(String certificatePath) {  
214.         return verifyCertificate(new Date(), certificatePath);  
215.     }  
216.   
217.     /** 
218.      * 验证Certificate是否过期或无效 
219.      *  
220.      * @param date 
221.      * @param certificatePath 
222.      * @return 
223.      */  
224.     public static boolean verifyCertificate(Date date, String certificatePath) {  
225.         boolean status = true;  
226.         try {  
227.             // 取得证书  
228.             Certificate certificate = getCertificate(certificatePath);  
229.             // 验证证书是否过期或无效  
230.             status = verifyCertificate(date, certificate);  
231.         } catch (Exception e) {  
232.             status = false;  
233.         }  
234.         return status;  
235.     }  
236.   
237.     /** 
238.      * 验证证书是否过期或无效 
239.      *  
240.      * @param date 
241.      * @param certificate 
242.      * @return 
243.      */  
244.     private static boolean verifyCertificate(Date date, Certificate certificate) {  
245.         boolean status = true;  
246.         try {  
247.             X509Certificate x509Certificate = (X509Certificate) certificate;  
248.             x509Certificate.checkValidity(date);  
249.         } catch (Exception e) {  
250.             status = false;  
251.         }  
252.         return status;  
253.     }  
254.   
255.     /** 
256.      * 签名 
257.      *  
258.      * @param keyStorePath 
259.      * @param alias 
260.      * @param password 
261.      *  
262.      * @return 
263.      * @throws Exception 
264.      */  
265.     public static String sign(byte[] sign, String keyStorePath, String alias,  
266.             String password) throws Exception {  
267.         // 获得证书  
268.         X509Certificate x509Certificate = (X509Certificate) getCertificate(  
269.                 keyStorePath, alias, password);  
270.         // 获取私钥  
271.         KeyStore ks = getKeyStore(keyStorePath, password);  
272.         // 取得私钥  
273.         PrivateKey privateKey = (PrivateKey) ks.getKey(alias, password  
274.                 .toCharArray());  
275.   
276.         // 构建签名  
277.         Signature signature = Signature.getInstance(x509Certificate  
278.                 .getSigAlgName());  
279.         signature.initSign(privateKey);  
280.         signature.update(sign);  
281.         return encryptBASE64(signature.sign());  
282.     }  
283.   
284.     /** 
285.      * 验证签名 
286.      *  
287.      * @param data 
288.      * @param sign 
289.      * @param certificatePath 
290.      * @return 
291.      * @throws Exception 
292.      */  
293.     public static boolean verify(byte[] data, String sign,  
294.             String certificatePath) throws Exception {  
295.         // 获得证书  
296.         X509Certificate x509Certificate = (X509Certificate) getCertificate(certificatePath);  
297.         // 获得公钥  
298.         PublicKey publicKey = x509Certificate.getPublicKey();  
299.         // 构建签名  
300.         Signature signature = Signature.getInstance(x509Certificate  
301.                 .getSigAlgName());  
302.         signature.initVerify(publicKey);  
303.         signature.update(data);  
304.   
305.         return signature.verify(decryptBASE64(sign));  
306.   
307.     }  
308.   
309.     /** 
310.      * 验证Certificate 
311.      *  
312.      * @param keyStorePath 
313.      * @param alias 
314.      * @param password 
315.      * @return 
316.      */  
317.     public static boolean verifyCertificate(Date date, String keyStorePath,  
318.             String alias, String password) {  
319.         boolean status = true;  
320.         try {  
321.             Certificate certificate = getCertificate(keyStorePath, alias,  
322.                     password);  
323.             status = verifyCertificate(date, certificate);  
324.         } catch (Exception e) {  
325.             status = false;  
326.         }  
327.         return status;  
328.     }  
329.   
330.     /** 
331.      * 验证Certificate 
332.      *  
333.      * @param keyStorePath 
334.      * @param alias 
335.      * @param password 
336.      * @return 
337.      */  
338.     public static boolean verifyCertificate(String keyStorePath, String alias,  
339.             String password) {  
340.         return verifyCertificate(new Date(), keyStorePath, alias, password);  
341.     }  
342.   
343.     /** 
344.      * 获得SSLSocektFactory 
345.      *  
346.      * @param password 
347.      *            密码 
348.      * @param keyStorePath 
349.      *            密钥库路径 
350.      *  
351.      * @param trustKeyStorePath 
352.      *            信任库路径 
353.      * @return 
354.      * @throws Exception 
355.      */  
356.     private static SSLSocketFactory getSSLSocketFactory(String password,  
357.             String keyStorePath, String trustKeyStorePath) throws Exception {  
358.         // 初始化密钥库  
359.         KeyManagerFactory keyManagerFactory = KeyManagerFactory  
360.                 .getInstance(SunX509);  
361.         KeyStore keyStore = getKeyStore(keyStorePath, password);  
362.         keyManagerFactory.init(keyStore, password.toCharArray());  
363.   
364.         // 初始化信任库  
365.         TrustManagerFactory trustManagerFactory = TrustManagerFactory  
366.                 .getInstance(SunX509);  
367.         KeyStore trustkeyStore = getKeyStore(trustKeyStorePath, password);  
368.         trustManagerFactory.init(trustkeyStore);  
369.   
370.         // 初始化SSL上下文  
371.         SSLContext ctx = SSLContext.getInstance(SSL);  
372.         ctx.init(keyManagerFactory.getKeyManagers(), trustManagerFactory  
373.                 .getTrustManagers(), null);  
374.         SSLSocketFactory sf = ctx.getSocketFactory();  
375.   
376.         return sf;  
377.     }  
378.   
379.     /** 
380.      * 为HttpsURLConnection配置SSLSocketFactory 
381.      *  
382.      * @param conn 
383.      *            HttpsURLConnection 
384.      * @param password 
385.      *            密码 
386.      * @param keyStorePath 
387.      *            密钥库路径 
388.      *  
389.      * @param trustKeyStorePath 
390.      *            信任库路径 
391.      * @throws Exception 
392.      */  
393.     public static void configSSLSocketFactory(HttpsURLConnection conn,  
394.             String password, String keyStorePath, String trustKeyStorePath)  
395.             throws Exception {  
396.         conn.setSSLSocketFactory(getSSLSocketFactory(password, keyStorePath,  
397.                 trustKeyStorePath));  
398.     }  
399. }  

import java.io.FileInputStream;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.util.Date;

import javax.crypto.Cipher;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManagerFactory;

/**
 * 证书组件
 * 
 * @author 梁栋
 * @version 1.0
 * @since 1.0
 */
public abstract class CertificateCoder extends Coder {

	/**
	 * Java密钥库(Java Key Store，JKS)KEY_STORE
	 */
	public static final String KEY_STORE = "JKS";

	public static final String X509 = "X.509";
	public static final String SunX509 = "SunX509";
	public static final String SSL = "SSL";

	/**
	 * 由KeyStore获得私钥
	 * 
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return
	 * @throws Exception
	 */
	private static PrivateKey getPrivateKey(String keyStorePath, String alias,
			String password) throws Exception {
		KeyStore ks = getKeyStore(keyStorePath, password);
		PrivateKey key = (PrivateKey) ks.getKey(alias, password.toCharArray());
		return key;
	}

	/**
	 * 由Certificate获得公钥
	 * 
	 * @param certificatePath
	 * @return
	 * @throws Exception
	 */
	private static PublicKey getPublicKey(String certificatePath)
			throws Exception {
		Certificate certificate = getCertificate(certificatePath);
		PublicKey key = certificate.getPublicKey();
		return key;
	}

	/**
	 * 获得Certificate
	 * 
	 * @param certificatePath
	 * @return
	 * @throws Exception
	 */
	private static Certificate getCertificate(String certificatePath)
			throws Exception {
		CertificateFactory certificateFactory = CertificateFactory
				.getInstance(X509);
		FileInputStream in = new FileInputStream(certificatePath);

		Certificate certificate = certificateFactory.generateCertificate(in);
		in.close();

		return certificate;
	}

	/**
	 * 获得Certificate
	 * 
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return
	 * @throws Exception
	 */
	private static Certificate getCertificate(String keyStorePath,
			String alias, String password) throws Exception {
		KeyStore ks = getKeyStore(keyStorePath, password);
		Certificate certificate = ks.getCertificate(alias);

		return certificate;
	}

	/**
	 * 获得KeyStore
	 * 
	 * @param keyStorePath
	 * @param password
	 * @return
	 * @throws Exception
	 */
	private static KeyStore getKeyStore(String keyStorePath, String password)
			throws Exception {
		FileInputStream is = new FileInputStream(keyStorePath);
		KeyStore ks = KeyStore.getInstance(KEY_STORE);
		ks.load(is, password.toCharArray());
		is.close();
		return ks;
	}

	/**
	 * 私钥加密
	 * 
	 * @param data
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return
	 * @throws Exception
	 */
	public static byte[] encryptByPrivateKey(byte[] data, String keyStorePath,
			String alias, String password) throws Exception {
		// 取得私钥
		PrivateKey privateKey = getPrivateKey(keyStorePath, alias, password);

		// 对数据加密
		Cipher cipher = Cipher.getInstance(privateKey.getAlgorithm());
		cipher.init(Cipher.ENCRYPT_MODE, privateKey);

		return cipher.doFinal(data);

	}

	/**
	 * 私钥解密
	 * 
	 * @param data
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return
	 * @throws Exception
	 */
	public static byte[] decryptByPrivateKey(byte[] data, String keyStorePath,
			String alias, String password) throws Exception {
		// 取得私钥
		PrivateKey privateKey = getPrivateKey(keyStorePath, alias, password);

		// 对数据加密
		Cipher cipher = Cipher.getInstance(privateKey.getAlgorithm());
		cipher.init(Cipher.DECRYPT_MODE, privateKey);

		return cipher.doFinal(data);

	}

	/**
	 * 公钥加密
	 * 
	 * @param data
	 * @param certificatePath
	 * @return
	 * @throws Exception
	 */
	public static byte[] encryptByPublicKey(byte[] data, String certificatePath)
			throws Exception {

		// 取得公钥
		PublicKey publicKey = getPublicKey(certificatePath);
		// 对数据加密
		Cipher cipher = Cipher.getInstance(publicKey.getAlgorithm());
		cipher.init(Cipher.ENCRYPT_MODE, publicKey);

		return cipher.doFinal(data);

	}

	/**
	 * 公钥解密
	 * 
	 * @param data
	 * @param certificatePath
	 * @return
	 * @throws Exception
	 */
	public static byte[] decryptByPublicKey(byte[] data, String certificatePath)
			throws Exception {
		// 取得公钥
		PublicKey publicKey = getPublicKey(certificatePath);

		// 对数据加密
		Cipher cipher = Cipher.getInstance(publicKey.getAlgorithm());
		cipher.init(Cipher.DECRYPT_MODE, publicKey);

		return cipher.doFinal(data);

	}

	/**
	 * 验证Certificate
	 * 
	 * @param certificatePath
	 * @return
	 */
	public static boolean verifyCertificate(String certificatePath) {
		return verifyCertificate(new Date(), certificatePath);
	}

	/**
	 * 验证Certificate是否过期或无效
	 * 
	 * @param date
	 * @param certificatePath
	 * @return
	 */
	public static boolean verifyCertificate(Date date, String certificatePath) {
		boolean status = true;
		try {
			// 取得证书
			Certificate certificate = getCertificate(certificatePath);
			// 验证证书是否过期或无效
			status = verifyCertificate(date, certificate);
		} catch (Exception e) {
			status = false;
		}
		return status;
	}

	/**
	 * 验证证书是否过期或无效
	 * 
	 * @param date
	 * @param certificate
	 * @return
	 */
	private static boolean verifyCertificate(Date date, Certificate certificate) {
		boolean status = true;
		try {
			X509Certificate x509Certificate = (X509Certificate) certificate;
			x509Certificate.checkValidity(date);
		} catch (Exception e) {
			status = false;
		}
		return status;
	}

	/**
	 * 签名
	 * 
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * 
	 * @return
	 * @throws Exception
	 */
	public static String sign(byte[] sign, String keyStorePath, String alias,
			String password) throws Exception {
		// 获得证书
		X509Certificate x509Certificate = (X509Certificate) getCertificate(
				keyStorePath, alias, password);
		// 获取私钥
		KeyStore ks = getKeyStore(keyStorePath, password);
		// 取得私钥
		PrivateKey privateKey = (PrivateKey) ks.getKey(alias, password
				.toCharArray());

		// 构建签名
		Signature signature = Signature.getInstance(x509Certificate
				.getSigAlgName());
		signature.initSign(privateKey);
		signature.update(sign);
		return encryptBASE64(signature.sign());
	}

	/**
	 * 验证签名
	 * 
	 * @param data
	 * @param sign
	 * @param certificatePath
	 * @return
	 * @throws Exception
	 */
	public static boolean verify(byte[] data, String sign,
			String certificatePath) throws Exception {
		// 获得证书
		X509Certificate x509Certificate = (X509Certificate) getCertificate(certificatePath);
		// 获得公钥
		PublicKey publicKey = x509Certificate.getPublicKey();
		// 构建签名
		Signature signature = Signature.getInstance(x509Certificate
				.getSigAlgName());
		signature.initVerify(publicKey);
		signature.update(data);

		return signature.verify(decryptBASE64(sign));

	}

	/**
	 * 验证Certificate
	 * 
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return
	 */
	public static boolean verifyCertificate(Date date, String keyStorePath,
			String alias, String password) {
		boolean status = true;
		try {
			Certificate certificate = getCertificate(keyStorePath, alias,
					password);
			status = verifyCertificate(date, certificate);
		} catch (Exception e) {
			status = false;
		}
		return status;
	}

	/**
	 * 验证Certificate
	 * 
	 * @param keyStorePath
	 * @param alias
	 * @param password
	 * @return
	 */
	public static boolean verifyCertificate(String keyStorePath, String alias,
			String password) {
		return verifyCertificate(new Date(), keyStorePath, alias, password);
	}

	/**
	 * 获得SSLSocektFactory
	 * 
	 * @param password
	 *            密码
	 * @param keyStorePath
	 *            密钥库路径
	 * 
	 * @param trustKeyStorePath
	 *            信任库路径
	 * @return
	 * @throws Exception
	 */
	private static SSLSocketFactory getSSLSocketFactory(String password,
			String keyStorePath, String trustKeyStorePath) throws Exception {
		// 初始化密钥库
		KeyManagerFactory keyManagerFactory = KeyManagerFactory
				.getInstance(SunX509);
		KeyStore keyStore = getKeyStore(keyStorePath, password);
		keyManagerFactory.init(keyStore, password.toCharArray());

		// 初始化信任库
		TrustManagerFactory trustManagerFactory = TrustManagerFactory
				.getInstance(SunX509);
		KeyStore trustkeyStore = getKeyStore(trustKeyStorePath, password);
		trustManagerFactory.init(trustkeyStore);

		// 初始化SSL上下文
		SSLContext ctx = SSLContext.getInstance(SSL);
		ctx.init(keyManagerFactory.getKeyManagers(), trustManagerFactory
				.getTrustManagers(), null);
		SSLSocketFactory sf = ctx.getSocketFactory();

		return sf;
	}

	/**
	 * 为HttpsURLConnection配置SSLSocketFactory
	 * 
	 * @param conn
	 *            HttpsURLConnection
	 * @param password
	 *            密码
	 * @param keyStorePath
	 *            密钥库路径
	 * 
	 * @param trustKeyStorePath
	 *            信任库路径
	 * @throws Exception
	 */
	public static void configSSLSocketFactory(HttpsURLConnection conn,
			String password, String keyStorePath, String trustKeyStorePath)
			throws Exception {
		conn.setSSLSocketFactory(getSSLSocketFactory(password, keyStorePath,
				trustKeyStorePath));
	}
}

增加了 configSSLSocketFactory方法供外界调用，该方法为HttpsURLConnection配置了SSLSocketFactory。当HttpsURLConnection配置了SSLSocketFactory后，我们就可以通过HttpsURLConnection的getInputStream、getOutputStream，像往常使用HttpURLConnection做操作了。尤其要说明一点，未配置SSLSocketFactory前，HttpsURLConnection的getContentLength()获得值永远都是 -1。

给出相应测试类：

Java代码  

1. import static org.junit.Assert.*;  
2.   
3. import java.io.DataInputStream;  
4. import java.io.InputStream;  
5. import java.net.URL;  
6.   
7. import javax.net.ssl.HttpsURLConnection;  
8.   
9. import org.junit.Test;  
10.   
11. /** 
12.  *  
13.  * @author 梁栋 
14.  * @version 1.0 
15.  * @since 1.0 
16.  */  
17. public class CertificateCoderTest {  
18.     private String password = "123456";  
19.     private String alias = "www.zlex.org";  
20.     private String certificatePath = "d:/zlex.cer";  
21.     private String keyStorePath = "d:/zlex.keystore";  
22.     private String clientKeyStorePath = "d:/zlex-client.keystore";  
23.     private String clientPassword = "654321";  
24.   
25.     @Test  
26.     public void test() throws Exception {  
27.         System.err.println("公钥加密——私钥解密");  
28.         String inputStr = "Ceritifcate";  
29.         byte[] data = inputStr.getBytes();  
30.   
31.         byte[] encrypt = CertificateCoder.encryptByPublicKey(data,  
32.                 certificatePath);  
33.   
34.         byte[] decrypt = CertificateCoder.decryptByPrivateKey(encrypt,  
35.                 keyStorePath, alias, password);  
36.         String outputStr = new String(decrypt);  
37.   
38.         System.err.println("加密前: " + inputStr + "\n\r" + "解密后: " + outputStr);  
39.   
40.         // 验证数据一致  
41.         assertArrayEquals(data, decrypt);  
42.   
43.         // 验证证书有效  
44.         assertTrue(CertificateCoder.verifyCertificate(certificatePath));  
45.   
46.     }  
47.   
48.     @Test  
49.     public void testSign() throws Exception {  
50.         System.err.println("私钥加密——公钥解密");  
51.   
52.         String inputStr = "sign";  
53.         byte[] data = inputStr.getBytes();  
54.   
55.         byte[] encodedData = CertificateCoder.encryptByPrivateKey(data,  
56.                 keyStorePath, alias, password);  
57.   
58.         byte[] decodedData = CertificateCoder.decryptByPublicKey(encodedData,  
59.                 certificatePath);  
60.   
61.         String outputStr = new String(decodedData);  
62.         System.err.println("加密前: " + inputStr + "\n\r" + "解密后: " + outputStr);  
63.         assertEquals(inputStr, outputStr);  
64.   
65.         System.err.println("私钥签名——公钥验证签名");  
66.         // 产生签名  
67.         String sign = CertificateCoder.sign(encodedData, keyStorePath, alias,  
68.                 password);  
69.         System.err.println("签名:\r" + sign);  
70.   
71.         // 验证签名  
72.         boolean status = CertificateCoder.verify(encodedData, sign,  
73.                 certificatePath);  
74.         System.err.println("状态:\r" + status);  
75.         assertTrue(status);  
76.   
77.     }  
78.   
79.     @Test  
80.     public void testHttps() throws Exception {  
81.         URL url = new URL("https://www.zlex.org/examples/");  
82.         HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();  
83.   
84.         conn.setDoInput(true);  
85.         conn.setDoOutput(true);  
86.   
87.         CertificateCoder.configSSLSocketFactory(conn, clientPassword,  
88.                 clientKeyStorePath, clientKeyStorePath);  
89.   
90.         InputStream is = conn.getInputStream();  
91.   
92.         int length = conn.getContentLength();  
93.   
94.         DataInputStream dis = new DataInputStream(is);  
95.         byte[] data = new byte[length];  
96.         dis.readFully(data);  
97.   
98.         dis.close();  
99.         System.err.println(new String(data));  
100.         conn.disconnect();  
101.     }  
102. }  

import static org.junit.Assert.*;

import java.io.DataInputStream;
import java.io.InputStream;
import java.net.URL;

import javax.net.ssl.HttpsURLConnection;

import org.junit.Test;

/**
 * 
 * @author 梁栋
 * @version 1.0
 * @since 1.0
 */
public class CertificateCoderTest {
	private String password = "123456";
	private String alias = "www.zlex.org";
	private String certificatePath = "d:/zlex.cer";
	private String keyStorePath = "d:/zlex.keystore";
	private String clientKeyStorePath = "d:/zlex-client.keystore";
	private String clientPassword = "654321";

	@Test
	public void test() throws Exception {
		System.err.println("公钥加密——私钥解密");
		String inputStr = "Ceritifcate";
		byte[] data = inputStr.getBytes();

		byte[] encrypt = CertificateCoder.encryptByPublicKey(data,
				certificatePath);

		byte[] decrypt = CertificateCoder.decryptByPrivateKey(encrypt,
				keyStorePath, alias, password);
		String outputStr = new String(decrypt);

		System.err.println("加密前: " + inputStr + "\n\r" + "解密后: " + outputStr);

		// 验证数据一致
		assertArrayEquals(data, decrypt);

		// 验证证书有效
		assertTrue(CertificateCoder.verifyCertificate(certificatePath));

	}

	@Test
	public void testSign() throws Exception {
		System.err.println("私钥加密——公钥解密");

		String inputStr = "sign";
		byte[] data = inputStr.getBytes();

		byte[] encodedData = CertificateCoder.encryptByPrivateKey(data,
				keyStorePath, alias, password);

		byte[] decodedData = CertificateCoder.decryptByPublicKey(encodedData,
				certificatePath);

		String outputStr = new String(decodedData);
		System.err.println("加密前: " + inputStr + "\n\r" + "解密后: " + outputStr);
		assertEquals(inputStr, outputStr);

		System.err.println("私钥签名——公钥验证签名");
		// 产生签名
		String sign = CertificateCoder.sign(encodedData, keyStorePath, alias,
				password);
		System.err.println("签名:\r" + sign);

		// 验证签名
		boolean status = CertificateCoder.verify(encodedData, sign,
				certificatePath);
		System.err.println("状态:\r" + status);
		assertTrue(status);

	}

	@Test
	public void testHttps() throws Exception {
		URL url = new URL("https://www.zlex.org/examples/");
		HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();

		conn.setDoInput(true);
		conn.setDoOutput(true);

		CertificateCoder.configSSLSocketFactory(conn, clientPassword,
				clientKeyStorePath, clientKeyStorePath);

		InputStream is = conn.getInputStream();

		int length = conn.getContentLength();

		DataInputStream dis = new DataInputStream(is);
		byte[] data = new byte[length];
		dis.readFully(data);

		dis.close();
		System.err.println(new String(data));
		conn.disconnect();
	}
}

注意 testHttps方法，几乎和我们往常做HTTP访问没有差别，我们来看控制台输出：

Console代码  

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通过浏览器直接访问 https://www.zlex.org/examples/你也会获得上述内容。也就是说应用甲方作为服务器构建tomcat服务，乙方可以通过上述方式访问甲方受保护的SSL应用，并且不需要考虑具体的加密解密问题。甲乙双方可以经过相应配置，通过双方的tomcat配置有效的SSL服务，简化上述代码实现，完全通过证书配置完成SSL双向认证！