JAVA数字证书
在构建Java代码实现前，我们需要完成证书的制作。
1.生成keyStroe文件
在命令行下执行以下命令：
keytool -genkey -validity 36000 -alias jlxrsa -keyalg RSA -keystore d:\jlxrsz.keystore
其中
-genkey表示生成密钥
-validity指定证书有效期，这里是36000天
-alias指定别名，这里是www.zlex.org
-keyalg指定算法，这里是RSA
-keystore指定存储位置，这里是d:\zlex.keystore
在这里我使用的密码为 123456
2.生成自签名证书
光有keyStore文件是不够的，还需要证书文件，证书才是直接提供给外界使用的公钥凭证。
导出证书：
keytool -export -keystore d:\jlxrsa.keystore -alias jlxrsa -file d:\jlxrsa.cer -rfc
其中
-export指定为导出操作
-keystore指定keystore文件
-alias指定导出keystore文件中的别名
-file指向导出路径
-rfc以文本格式输出，也就是以BASE64编码输出
这里的密码是 123456
Ok，准备工作完成，开始Java实现！
package cert;
import java.security.MessageDigest;
import javax.crypto.KeyGenerator;
import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
/**
* 基础加密组件
*
* @author
* @version 1.0
* @since 1.0
*/
public abstract class Coder {
public static final String KEY_SHA = "SHA";
public static final String KEY_MD5 = "MD5";
/**
* MAC算法可选以下多种算法
*
* <pre>
* HmacMD5
* HmacSHA1
* HmacSHA256
* HmacSHA384
* HmacSHA512
* </pre>
*/
public static final String KEY_MAC = "HmacMD5";
/**
* BASE64解密
*
* @param key
* @return
* @throws Exception
*/
public static byte[] decryptBASE64(String key) throws Exception {
return (new BASE64Decoder()).decodeBuffer(key);
}
/**
* BASE64加密
*
* @param key
* @return
* @throws Exception
*/
public static String encryptBASE64(byte[] key) throws Exception {
return (new BASE64Encoder()).encodeBuffer(key);
}
/**
* MD5加密
*
* @param data
* @return
* @throws Exception
*/
public static byte[] encryptMD5(byte[] data) throws Exception {
MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);
md5.update(data);
return md5.digest();
}
/**
* SHA加密
*
* @param data
* @return
* @throws Exception
*/
public static byte[] encryptSHA(byte[] data) throws Exception {
MessageDigest sha = MessageDigest.getInstance(KEY_SHA);
sha.update(data);
return sha.digest();
}
/**
* 初始化HMAC密钥
*
* @return
* @throws Exception
*/
public static String initMacKey() throws Exception {
KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_MAC);
SecretKey secretKey = keyGenerator.generateKey();
return encryptBASE64(secretKey.getEncoded());
}
/**
* HMAC加密
*
* @param data
* @param key
* @return
* @throws Exception
*/
public static byte[] encryptHMAC(byte[] data, String key) throws Exception {
SecretKey secretKey = new SecretKeySpec(decryptBASE64(key), KEY_MAC);
Mac mac = Mac.getInstance(secretKey.getAlgorithm());
mac.init(secretKey);
return mac.doFinal(data);
}
}
package cert;
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;
/**
* 证书组件
*
* @author
* @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";
/**
* 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);
}
}
package cert;
import static org.junit.Assert.*;
import org.junit.Test;
/**
*
* @author
* @version 1.0
* @since 1.0
*/
public class CertificateCoderTest {
private String password = "123456";
private String alias = "jlxrsa";
private String certificatePath = "d:/jlx.cer";
private String keyStorePath = "d:/jlx.keystore";
@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);
}
}
