数字证书应用综合揭秘（包括证书生成、加密、解密、签名、验签）

keytool -genkey -alias casserver -keypass cas123 -keyalg RSA -keystore casserver.keystore -validity 365
keytool -export -alias casserver -storepass cas123 -file casserver.cer -keystore casserver.keystore
keytool -import -trustcacerts -alias casserver -storepass cas123 -file casserver.cer –keystore cacerts

keytool -genkey -alias everygold -keypass 123456 -keyalg RSA -keystore leslie.keystore -validity 365

keytool -export -alias everygold -storepass 123456 -file leslie.cer -keystore leslie.keystore

-----BEGIN CERTIFICATE-----
MIICRjCCAa+gAwIBAgIEIvzKsDANBgkqhkiG9w0BAQsFADBWMQswCQYDVQQGEwJD
TjELMAkGA1UECBMCR0QxCzAJBgNVBAcTAkdaMQ4wDAYDVQQKEwVwdWppbjEMMAoG
A1UECxMDU3VuMQ8wDQYDVQQDEwZMZXNsaWUwHhcNMTcwODI5MDMwMjE4WhcNMTgw
ODI5MDMwMjE4WjBWMQswCQYDVQQGEwJDTjELMAkGA1UECBMCR0QxCzAJBgNVBAcT
AkdaMQ4wDAYDVQQKEwVwdWppbjEMMAoGA1UECxMDU3VuMQ8wDQYDVQQDEwZMZXNs
aWUwgZ8wDQYJKoZIhvcNAQEBBQADgY0AMIGJAoGBAKFVrCaKFi2GtJjyuWSPrJah
.........................
-----END CERTIFICATE-----

keytool -list  -rfc -keystore d:/leslie.keystore -storepass 123456

 1 public class CerTest {  
 2     public static void main(String[] args){
 3              CerTest test=new CerTest();
 4              //生成 keystore 文件
 5              test.getKeyStore();
 6              //生成 *.cer 证书文件
 7              test.export();
 8     }
 9 
10     public void execCommand(String[] arstringCommand) {  
11         for (int i = 0; i < arstringCommand.length; i++) {  
12             System.out.print(arstringCommand[i] + " ");  
13         }  
14         try {  
15             Runtime.getRuntime().exec(arstringCommand);  
16   
17         } catch (Exception e) {  
18             System.out.println(e.getMessage());  
19         }  
20     }  
21 
22     public void execCommand(String arstringCommand) {  
23         try {  
24             Runtime.getRuntime().exec(arstringCommand);  
25               
26         } catch (Exception e) {  
27             System.out.println(e.getMessage());  
28         }  
29     }  
30   
31     /** 
32      * 生成 *.keystore 
33      */  
34     public void getKeyStore() {  
35         String[] arstringCommand = new String[] {  
36   
37         "cmd ", "/k",  
38                 "start", // cmd Shell命令  
39   
40                 "keytool",  
41                 "-genkey", // -genkey表示生成密钥  
42                 "-validity", // -validity指定证书有效期(单位：天)，这里是365天  
43                 "365",  
44                 "-keysize",//     指定密钥长度  
45                 "1024",  
46                 "-alias", // -alias指定别名，这里是everygold 
47                 "everygold",  
48                 "-keyalg", // -keyalg 指定密钥的算法 (如 RSA DSA（如果不指定默认采用DSA）)  
49                 "RSA",  
50                 "-keystore", // -keystore指定存储位置，这里是d:/leslie.keystore  
51                 "d:/leslie.keystore",  
52                 "-dname",// CN=(名字与姓氏), OU=(组织单位名称), O=(组织名称), L=(城市或区域名称),  
53                             // ST=(州或省份名称), C=(单位的两字母国家代码)"  
54                 "CN=(leslie), OU=(everygold), O=(pujinwang), L=(Guangzhou), ST=(Guangdong), C=(CN)",  
55                 "-storepass", // 指定密钥库的密码(获取keystore信息所需的密码)  
56                 "123456",   
57                 "-keypass",// 指定别名条目的密码(私钥的密码)  
58                 "123456",   
59                 "-v"// -v 显示密钥库中的证书详细信息  
60         };  
61         execCommand(arstringCommand);  
62     }  
63   
64     /** 
65      * 导出证书文件 
66      */  
67     public void export() {  
68   
69         String[] arstringCommand = new String[] {  
70   
71         "cmd ", "/k",  
72                 "start", // cmd Shell命令  
73                 "keytool",  
74                 "-export", // - export指定为导出操作   
75                 "-keystore", // -keystore指定keystore文件，这里是d:/leslie.keystore  
76                 "d:/leslie.keystore",  
77                 "-alias", // -alias指定别名，这里是ss  
78                 "everygold",  
79                 "-file",//-file指向导出路径  
80                 "d:/leslie.cer",  
81                 "-storepass",// 指定密钥库的密码  
82                 "123456"   
83         };  
84         execCommand(arstringCommand);  
85       
86     }  
87 }  

  1 public abstract class Coder {
  2 
  3     /**
  4      * BASE64解密
  5      * 
  6      * @param key
  7      * @return
  8      * @throws Exception
  9      */
 10     public static byte[] decryptBASE64(String key) throws Exception {
 11         return (new BASE64Decoder()).decodeBuffer(key);
 12     }
 13 
 14     /**
 15      * BASE64加密
 16      * 
 17      * @param key
 18      * @return
 19      * @throws Exception
 20      */
 21     public static String encryptBASE64(byte[] key) throws Exception {
 22         return (new BASE64Encoder()).encodeBuffer(key).replace("r", "").replace("n", "");
 23     }
 24 }
 25 
 26 public class MyCoder extends Coder{
 27 
 28     /**
 29      * 使用公钥加密数据
 30      * @param publicKey
 31      * @param srcData
 32      * @return
 33      * @throws Exception
 34      */
 35     public static String encryptByPublicKey(String publicKey, String srcData) throws Exception{
 36         //解密
 37         byte[] pk = Coder.decryptBASE64(publicKey);
 38         X509EncodedKeySpec spec = new X509EncodedKeySpec(pk);
 39         KeyFactory kf = KeyFactory.getInstance("RSA");
 40         //获取公钥
 41         PublicKey pubKey = kf.generatePublic(spec);
 42         
 43         // 对数据加密
 44         Cipher cipher = Cipher.getInstance("RSA");
 45         cipher.init(Cipher.ENCRYPT_MODE, pubKey);
 46         
 47         byte[] doFinal = cipher.doFinal(srcData.getBytes());
 48         return encryptBASE64(doFinal);
 49     }
 50     
 51     
 52     /*
 53      * 使用私钥解密数据
 54      * @param privateKey
 55      * @param data
 56      * @return
 57      * @throws Exception
 58      */
 59     public static String descryptByPrivateKey(String privateKey, String data) throws Exception{
 60         // BASE64转码解密私钥
 61         byte[] pk = Coder.decryptBASE64(privateKey);
 62         // BASE64转码解密密文
 63         byte[] text = decryptBASE64(data);
 64         PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(pk);
 65         KeyFactory kf = KeyFactory.getInstance("RSA");
 66         // 获取私钥
 67         PrivateKey prvKey = kf.generatePrivate(spec);
 68         
 69         // 对数据加密
 70         Cipher cipher = Cipher.getInstance("RSA");
 71         cipher.init(Cipher.DECRYPT_MODE, prvKey);
 72         
 73         byte[] doFinal = cipher.doFinal(text);
 74         return new String(doFinal);
 75     }
 76 
 77     public static void main(){
 78         // 公钥
 79         String strPublicKey = "";
 80         // 私钥
 81         String strPrivateKey = "";
 82         
 83         try {
 84             strPublicKey = KeyStoreTool.getStrPublicKey("d://leslie.keystore", "everygold", "123456");
 85             strPrivateKey = KeyStoreTool.getStrPrivateKey("d://leslie.keystore", "everygold", "123456", "123456");
 86         } catch (Exception e1) {
 87             e1.printStackTrace();
 88         }
 89         
 90         // 原文
 91         String originalText = "原文 = 虽然我穷，但是再穷也要去旅游！";        
 92         System.out.println(originalText);
 93 
 94         try {
 95             // RSA算法 公钥加密随机数
 96             String secretText = MyCoder.encryptByPublicKey(strPublicKey, originalText);
 97             System.out.println("n经RSA公钥加密后 = " + secretText);
 98             System.out.println("n经RSA公钥加密后长度 = " + secretText.length());
 99             
100             String text = MyCoder.descryptByPrivateKey(strPrivateKey, secretText);
101             System.out.println("n经RSA私钥解密后 = 【" + text + "】");
102             System.out.println("n经RSA私钥解密后长度 = 【" + text.length() + "】");
103             
104         } catch (Exception e) {
105             e.printStackTrace();
106         }
107     }
108 }