RSA加密例子和中途遇到的有关问题
RSA加密例子和中途遇到的问题
在进行RSA加密例子
测试类
遇到的问题在
解密的时候 用new BASE64Encoder()).encode(keyBytes); 获得明文发现明文长度只能是4的倍数而且不支持特殊字符串和中文不然解密出来不是多出来 就是解密不对 后面解密
直接用.getBytes() 和new String(decodedData)不用Base64的就好了
在进行RSA加密例子
package test;
import java.io.IOException;
import java.security.Key;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
import java.util.HashMap;
import java.util.Map;
import javax.crypto.Cipher;
public abstract class RSACoder {
public static final String KEY_ALGORITHM = "RSA";
public static final String SIGNATURE_ALGORITHM = "MD5withRSA";
private static final String PUBLIC_KEY = "RSAPublicKey";
private static final String PRIVATE_KEY = "RSAPrivateKey";
public static byte[] decryptBASE64(String privateKey){
byte[] output = null;
try {
output = (new BASE64Decoder()).decodeBuffer(privateKey);
return output;
} catch (IOException e) {
e.printStackTrace();
}
return output;
}
public static String encryptBASE64( byte[] keyBytes){
String s = (new BASE64Encoder()).encode(keyBytes);
return s;
}
/**
* 用私钥对信息生成数字签名
*
* @param data
* 加密数据
* @param privateKey
* 私钥
*
* @return
* @throws Exception
*/
public static String sign(byte[] data, String privateKey) throws Exception {
// 解密由base64编码的私钥
byte[] keyBytes = decryptBASE64(privateKey);
// 构造PKCS8EncodedKeySpec对象
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
// KEY_ALGORITHM 指定的加密算法
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
// 取私钥匙对象
PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);
// 用私钥对信息生成数字签名
Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
signature.initSign(priKey);
signature.update(data);
return encryptBASE64(signature.sign());
}
/**
* 校验数字签名
*
* @param data
* 加密数据
* @param publicKey
* 公钥
* @param sign
* 数字签名
*
* @return 校验成功返回true 失败返回false
* @throws Exception
*
*/
public static boolean verify(byte[] data, String publicKey, String sign)
throws Exception {
// 解密由base64编码的公钥
byte[] keyBytes = decryptBASE64(publicKey);
// 构造X509EncodedKeySpec对象
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
// KEY_ALGORITHM 指定的加密算法
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
// 取公钥匙对象
PublicKey pubKey = keyFactory.generatePublic(keySpec);
Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
signature.initVerify(pubKey);
signature.update(data);
// 验证签名是否正常
return signature.verify(decryptBASE64(sign));
}
/**
* 解密<br>
* 用私钥解密
*
* @param data
* @param key
* @return
* @throws Exception
*/
public static byte[] decryptByPrivateKey(byte[] data, String key)
throws Exception {
// 对密钥解密
byte[] keyBytes = decryptBASE64(key);
// 取得私钥
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);
// 对数据解密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.DECRYPT_MODE, privateKey);
return cipher.doFinal(data);
}
/**
* 解密<br>
* 用公钥解密
*
* @param data
* @param key
* @return
* @throws Exception
*/
public static byte[] decryptByPublicKey(byte[] data, String key)
throws Exception {
// 对密钥解密
byte[] keyBytes = decryptBASE64(key);
// 取得公钥
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
Key publicKey = keyFactory.generatePublic(x509KeySpec);
// 对数据解密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.DECRYPT_MODE, publicKey);
return cipher.doFinal(data);
}
/**
* 加密<br>
* 用公钥加密
*
* @param data
* @param key
* @return
* @throws Exception
*/
public static byte[] encryptByPublicKey(byte[] data, String key)
throws Exception {
// 对公钥解密
byte[] keyBytes = decryptBASE64(key);
// 取得公钥
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
Key publicKey = keyFactory.generatePublic(x509KeySpec);
// 对数据加密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
return cipher.doFinal(data);
}
/**
* 加密<br>
* 用私钥加密
*
* @param data
* @param key
* @return
* @throws Exception
*/
public static byte[] encryptByPrivateKey(byte[] data, String key)
throws Exception {
// 对密钥解密
byte[] keyBytes = decryptBASE64(key);
// 取得私钥
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);
// 对数据加密
Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
cipher.init(Cipher.ENCRYPT_MODE, privateKey);
return cipher.doFinal(data);
}
/**
* 取得私钥
*
* @param keyMap
* @return
* @throws Exception
*/
public static String getPrivateKey(Map<String, Object> keyMap)
throws Exception {
Key key = (Key) keyMap.get(PRIVATE_KEY);
return encryptBASE64(key.getEncoded());
}
/**
* 取得公钥
*
* @param keyMap
* @return
* @throws Exception
*/
public static String getPublicKey(Map<String, Object> keyMap)
throws Exception {
Key key = (Key) keyMap.get(PUBLIC_KEY);
return encryptBASE64(key.getEncoded());
}
/**
* 初始化密钥
*
* @return
* @throws Exception
*/
public static Map<String, Object> initKey() throws Exception {
KeyPairGenerator keyPairGen = KeyPairGenerator
.getInstance(KEY_ALGORITHM);
keyPairGen.initialize(1024);
KeyPair keyPair = keyPairGen.generateKeyPair();
// 公钥
RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
// 私钥
RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
Map<String, Object> keyMap = new HashMap<String, Object>(2);
keyMap.put(PUBLIC_KEY, publicKey);
keyMap.put(PRIVATE_KEY, privateKey);
return keyMap;
}
}
测试类
package test;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
public class RSACoderTest {
public void getKey() throws Exception {
Map<String, Object> keyMap = RSACoder.initKey();
publicKey = RSACoder.getPublicKey(keyMap);
privateKey = RSACoder.getPrivateKey(keyMap);
System.out.println("public : "+publicKey);
System.out.println("private : "+privateKey);
}
public static void main(String[] args) throws Exception {
// System.err.println("公钥加密——私钥解密");
//将明文转换为字节数组
byte[] data = "NaUxcheADDc34m?(^%hj3&".getBytes();
//用公钥加密
byte[] encodedData = RSACoder.encryptByPublicKey(data, "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDELMnCJQgdIzzkcjcAe547dDCoGo/xB4xmhHDD"
+"N/DQVwDuzLPcctv5vQjBzbIZqU8OTWXfbxqBaEpfN91ZIwqnzWJQt/Piu3I95Yce1g7+aoHgOK/k"
+"8SEYV5W4Ikj3BmR2kLvb7DE2wbyWKqIhJL6Jx7PShqacghGxvCQ/qrXG9QIDAQAB");
//打印加密字符串 为什么使用BASE64Encoder 因为在RSACoder里加密用的是 BASE64Encoder 加密
String s = (new BASE64Encoder()).encode(encodedData);
System.err.println("加密: " +s);
//用私钥解密
byte[] decodedData = RSACoder.decryptByPrivateKey(RSACoder.decryptBASE64(s),"MIICdwIBADANBgkqhkiG9w0BAQEFAASCAmEwggJdAgEAAoGBAMQsycIlCB0jPORyNwB7njt0MKga"
+"j/EHjGaEcMM38NBXAO7Ms9xy2/m9CMHNshmpTw5NZd9vGoFoSl833VkjCqfNYlC38+K7cj3lhx7W"
+"Dv5qgeA4r+TxIRhXlbgiSPcGZHaQu9vsMTbBvJYqoiEkvonHs9KGppyCEbG8JD+qtcb1AgMBAAEC"
+"gYB0pdEeYRivArn9eLCd1+OhpJgeDRVUE9H3T38hhYzqxSEn3Y6BYcbNfArN+nqRaaw5a+pMbmsL"
+"UbEPZ0915jE5xBeB0PhM6sdITDSlcuXvN2nTO5u3ndEL02VvjOTwBea9luZOUCeQblu58t9E4Ust"
+"16oZzYPriCeEIge85HPhAQJBAPkFc4wDRR9eIXSKml7JlPXeGCM/5/vjqaBRV/LJP6YHtnbVIQbp"
+"don1q3WbFLIrxJ6gSVBQ0M+J6ay8/pmWcrUCQQDJrDPI+OZ7kM88RkYFWZeW9tcBo0lXslev/+x4"
+"ptSjImy5xebZE0VwDi3IVwTFWK7soDH+bOmvlJiqXIU47WtBAkEA5nS4EWx5TOVFWuBmqrAtrjjC"
+"5+Rdocx4kAiXtvWudM4Qe/sUHJx0+ookCqvhxF4jEZZPIwgXpuoAGr+xc5w7PQJACrcFgVYIGOSW"
+"viMVsU8TSMgQoFuml+w30HgOflKO1aQMlso2+62UcOGv+Qb2j+2oTZYtUdFDkTqZ6eNEiMPEgQJB"
+"ANAXRMqNnGHS4YYVdzcFRZ8wRUrYJYD1kCHH7IDGWFVqdQjo89OhSRdmAu6I7feFgbq+KuukSZvY"
+"LtY7Xz9dkKc=");
System.out.println( "解密后: " + new String(decodedData));
}
}
遇到的问题在
解密的时候 用new BASE64Encoder()).encode(keyBytes); 获得明文发现明文长度只能是4的倍数而且不支持特殊字符串和中文不然解密出来不是多出来 就是解密不对 后面解密
直接用.getBytes() 和new String(decodedData)不用Base64的就好了