RSA

收银台：请求数据+私钥做md5签名 BigInteger对请求参数做对称可逆加密

1.对称加密：一般小于256 bit的密钥，密钥越大越安全，但是解密和加密时间越长。加密和解密都是用的相同的密钥，快速简单
2.非对称加密：有公钥和私钥，只有私钥才能打开公钥，比如：你向银行请求公钥，银行将公钥发给你，你使用公钥对消息加密，那么只有私钥的持有人--银行才能对你的消息解密。与对称加密不同的是，银行不需要将私钥通过网络发送出去，因此安全性大大提高。但是速度慢

DES：Data Encrytion Standard（数据加密标准），对应算法是DEA
特点：1. 对称加密 2. 同一个SK
AES：Advanced Encrytion Standard（高级加密标准）
特点：1. 对称加密 2. 一个SK扩展成多个子SK，轮加密
RSA：特点： 1. 非对称加密，即：PK与SK不是同一个
2. PK用于加密，SK用于解密
3. PK决定SK，但是PK很难算出SK（数学原理：两个大质数相乘，积很难因式分解）
4. 速度慢，只对少量数据加密
公钥负责加密，私钥负责解密。私钥负责签名，公钥负责验证。公钥就是给大家用的，私钥就是给自己用的，必须小心保存

http://web.chacuo.net/netrsakeypair  生成私钥公钥

package com.creditease.yiqifin.bmow.base;
import com.creditease.yiqifin.bmow.base.security.RSAUtil;
public class RSAtest {
	public static void main(String[] args) {
		test("werretretrytryfgdfgtgrtgdfgsdgreg2");
	}
	public static void test(String source){
		String skey = "MIICdwIBADANBgkqhkiG9w0BAQEFAASCAmEwggJdAgEAAoGBAN2jaknBAxBgFY08"+
"kqy1jGWzNHFLU9h7E1QFwjrzdsJphpKQhmDNO1kaaAeuYkf59BgnhxGKmz6AqCLz"+
"7wV5BeQexYws4B6xHkQ8+vtWUioKb5LI7ZYDgs5V06U6u+LhwL72RgUR/sQ1OjzO"+
"iIEPhtffTlVs2EjCpnokzPCJqPUtAgMBAAECgYEAzxUtbQXix/0Ohe0PmkDykd8z"+
"Y5ufFohAEeRjitMJpjIUo4JXm8CF8AXFJ1Ae0eNP1vWvtIsN7AMnlajXLgTao4Fv"+
"bnOxep2fw2GSlFIuBnIN0bWJIpeQfWcC0pxvQ6pORBxg6Ys3JntahLXbc4RD1sol"+
"dRYQ8YXBREQTB/VtIoECQQD1ZH1VrRkPp2Yg3kGe2X/XOs2TZ8ZNjFFF4YOBbeE6"+
"gPzdimkWdDo2+q6frAeojCKeCvGpCKpHzyxHgEkvlLLhAkEA5zgP3lpVEqxfc9hv"+
"/5zq7zjI7J1+qwz9TgVMQft9k6iI0mEJrklMtrlVA41ZBgWi45JRMRmVHK7Z4oDT"+
"P3OXzQJAVVGFCj7O0dR/+7mK0zIH8sstIq0YE2pP754C3QNZJcAnKteuxfHPM8Jg"+
"6H8lgoKGnrBraTvsCF+No6aEy5hFwQJBALTT3WUyFFJ0SHpbDMxFtl68dDbIvWWc"+
"1QWNkyQPQRiXt9mAVofdf4dvzhLnGnZhNhDwP1s8/KbgADrqMUvwZQkCQC+/qHzE"+
"KQ/Wx2kJZ1oUuxyJ95iPp9ORnvpuTxi7sK5VW0QAIxWvpi9snGJJ45F5XU5dwWd2"+
"J9O7Z+0BVquuiJs=";
		String sign = "";
		try {
			sign = RSAUtil.sign(source, skey);
		} catch (Exception e) {
			e.printStackTrace();
		}
		System.out.println(source);
		System.out.println("密文："+sign);
		
		String pkey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDdo2pJwQMQYBWNPJKstYxlszRx"+
"S1PYexNUBcI683bCaYaSkIZgzTtZGmgHrmJH+fQYJ4cRips+gKgi8+8FeQXkHsWM"+
"LOAesR5EPPr7VlIqCm+SyO2WA4LOVdOlOrvi4cC+9kYFEf7ENTo8zoiBD4bX305V"+
"bNhIwqZ6JMzwiaj1LQIDAQAB";
		boolean verifySign = false;
		try {
			verifySign = RSAUtil.verifySign(source,sign,pkey);
		} catch (Exception e) {
			e.printStackTrace();
		}
		System.out.println("验证签名："+verifySign);
	
	}
}

　　

package com.creditease.yiqifin.bmow.base.security;

import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.StringUtils;
import com.creditease.yiqifin.bmow.base.exception.EncryptException;
import com.creditease.yiqifin.bmow.base.exception.SignException;

public class RSAUtil {
    private static final Logger logger = LoggerFactory.getLogger(RSAUtil.class);

    private static final String SIGN_ALGORITHMS = "SHA1WithRSA";
    private static final String RSA_ALGORITHM = "RSA";
    public static final String _CHARSET_NAME = "UTF-8";
    static private final int BASELENGTH = 128;
    static private final int LOOKUPLENGTH = 64;
    static private final int TWENTYFOURBITGROUP = 24;
    static private final int EIGHTBIT = 8;
    static private final int SIXTEENBIT = 16;
    static private final int FOURBYTE = 4;
    static private final int SIGN = -128;
    static private final char PAD = '=';
    static private final boolean fDebug = false;
    static final private byte[] base64Alphabet = new byte[BASELENGTH];
    static final private char[] lookUpBase64Alphabet = new char[LOOKUPLENGTH];
    /**
     * 默认密钥字节数
     * 
     * <pre>
     *  
     * DSA  
     * Default Keysize 1024   
     * Keysize must be a multiple of 64, ranging from 512 to 1024 (inclusive).
     * </pre>
     */
    private static final int KEY_SIZE = 1024;
    // 获取DSA公钥的key
    private final static String PUBLIC_RKEY = "RSAPublicKey";
    // 获取DSA私钥的key
    private final static String PRIVATE_RKEY = "RSAPrivateKey";

    static {
        for (int i = 0; i < BASELENGTH; ++i) {
            base64Alphabet[i] = -1;
        }
        for (int i = 'Z'; i >= 'A'; i--) {
            base64Alphabet[i] = (byte) (i - 'A');
        }
        for (int i = 'z'; i >= 'a'; i--) {
            base64Alphabet[i] = (byte) (i - 'a' + 26);
        }

        for (int i = '9'; i >= '0'; i--) {
            base64Alphabet[i] = (byte) (i - '0' + 52);
        }

        base64Alphabet['+'] = 62;
        base64Alphabet['/'] = 63;

        for (int i = 0; i <= 25; i++) {
            lookUpBase64Alphabet[i] = (char) ('A' + i);
        }

        for (int i = 26, j = 0; i <= 51; i++, j++) {
            lookUpBase64Alphabet[i] = (char) ('a' + j);
        }

        for (int i = 52, j = 0; i <= 61; i++, j++) {
            lookUpBase64Alphabet[i] = (char) ('0' + j);
        }
        lookUpBase64Alphabet[62] = (char) '+';
        lookUpBase64Alphabet[63] = (char) '/';

    }

    /**
     * RSA签名
     * 
     * @param content 待签名数据
     * @param privateKey 商户私钥
     * @return 签名值
     * @throws Exception
     */
    public static String sign(String content, String privateKey) throws Exception {
        PrivateKey priKey = getPrivateKey(privateKey);
        java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);
        signature.initSign(priKey);
        signature.update(content.getBytes(_CHARSET_NAME));
        byte[] signed = signature.sign();
        String signInfo = encode(signed);
        logger.info("rsa sign content : 
content:{}
privateKey:{}
signInfo:{}", content,
                privateKey, signInfo);
        return signInfo;
    }

    /**
     * RSA验签名检查
     * 
     * @param content 待签名数据
     * @param sign 签名值
     * @param pubKeyStr 支付宝公钥
     * @param input_charset 编码格式
     * @return 布尔值
     * @throws Exception
     */
    public static boolean verifySign(String content, String sign, String pubKeyStr)
            throws Exception {
        try {
            PublicKey pubKey = getPublicKey(pubKeyStr);
            java.security.Signature signature =
                    java.security.Signature.getInstance(SIGN_ALGORITHMS);
            signature.initVerify(pubKey);
            signature.update(content.getBytes(_CHARSET_NAME));
            byte[] decode = decode(sign);
            boolean bverify = false;
            if (decode != null && decode.length > 0) {
                bverify = signature.verify(decode);
            }
            logger.info(
                    "rsa verify signed content : 
content:{}
signInfo:{}
publicKey:{}
result:{}",
                    content, sign, pubKeyStr, bverify);

            return bverify;
        } catch (SignException e) {
            String message = e.getMessage();
            if (StringUtils.isEmpty(message)) {
                message = "数据验签失败";
            } else if (message.indexOf("Signature length not correct") >= 0) {
                message = "数据验签失败，signInfo长度错误，请发送密钥加签后的字符串，而不是密钥本身";
            }
            throw new SignException(message, e);
        } catch (Exception e) {
            throw e;
        }
    }

    /**
     * 使用公钥加密
     * 
     * @param plainContent
     * @param publicKeyString
     * @return
     * @throws Exception
     */
    public static String encryptWithPublicKey(String plainContent, String publicKeyString)
            throws Exception {
        PublicKey publicKey = getPublicKey(publicKeyString);
        byte[] plainContentData = plainContent.getBytes(_CHARSET_NAME);
        if (publicKey == null) {
            throw new EncryptException("加密公钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);
            byte[] output = cipher.doFinal(plainContentData);
            return encode(output);
        } catch (NoSuchAlgorithmException e) {
            throw new EncryptException("无此加密算法", e);
        } catch (InvalidKeyException e) {
            throw new EncryptException("加密公钥非法,请检查", e);
        } catch (IllegalBlockSizeException e) {
            throw new EncryptException("明文长度非法", e);
        } catch (BadPaddingException e) {
            throw new EncryptException("明文数据已损坏", e);
        }
    }

    /**
     * 使用私钥对数据进行加密
     * 
     * @param plainContent 明文数据
     * @param privateKeyString 私钥字符串
     * @return
     * @throws Exception 加密过程中的异常信息
     */
    public static String encryptWithPrivateKey(String plainContent, String privateKeyString)
            throws Exception {
        PrivateKey privateKey = getPrivateKey(privateKeyString);
        byte[] plainContentData = plainContent.getBytes(_CHARSET_NAME);
        if (privateKey == null) {
            throw new EncryptException("加密私钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, privateKey);
            byte[] output = cipher.doFinal(plainContentData);
            return encode(output);
        } catch (NoSuchAlgorithmException e) {
            throw new EncryptException("无此加密算法", e);
        } catch (InvalidKeyException e) {
            throw new EncryptException("加密私钥非法,请检查", e);
        } catch (IllegalBlockSizeException e) {
            throw new EncryptException("明文长度非法", e);
        } catch (BadPaddingException e) {
            throw new EncryptException("明文数据已损坏", e);
        } catch (Throwable e) {
            throw new EncryptException("数据加密失败", e);
        }
    }

    /**
     * 私钥解密过程
     * 
     * @param privateKey 私钥
     * @param cipherData 密文数据
     * @return 明文
     * @throws Exception 解密过程中的异常信息
     */
    public static String decryptWithPrivateKey(String cipherContent, String privateKeyString)
            throws Exception {
        byte[] cipherContentData = decode(cipherContent);
        PrivateKey privateKey = getPrivateKey(privateKeyString);
        if (privateKey == null) {
            throw new EncryptException("解密私钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] output = cipher.doFinal(cipherContentData);
            return new String(output);
        } catch (NoSuchAlgorithmException e) {
            throw new EncryptException("无此解密算法");
        } catch (InvalidKeyException e) {
            throw new EncryptException("解密私钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
            throw new EncryptException("密文长度非法");
        } catch (BadPaddingException e) {
            throw new EncryptException("密文数据已损坏");
        } catch (Throwable e) {
            throw new EncryptException("数据解密失败", e);
        }
    }

    /**
     * 公钥解密
     * 
     * @param cipherContent
     * @param publicKeyString
     * @return
     * @throws Exception
     */
    public static String decryptWithPublicKey(String cipherContent, String publicKeyString)
            throws Exception {
        byte[] cipherContentData = decode(cipherContent);
        PublicKey publicKey = getPublicKey(publicKeyString);
        if (publicKey == null) {
            throw new EncryptException("解密公钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE, publicKey);
            byte[] output = cipher.doFinal(cipherContentData);
            return new String(output);
        } catch (NoSuchAlgorithmException e) {
            throw new EncryptException("无此解密算法");
        } catch (InvalidKeyException e) {
            throw new EncryptException("解密公钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
            throw new EncryptException("密文长度非法");
        } catch (BadPaddingException e) {
            throw new EncryptException("密文数据已损坏");
        } catch (Throwable e) {
            throw new EncryptException("数据解密失败", e);
        }
    }

    /**
     * 得到私钥
     * 
     * @param key 密钥字符串（经过base64编码）
     * @throws Exception
     */
    private static PrivateKey getPrivateKey(String priKey) throws Exception {
        byte[] priKeyBytes = decode(priKey);
        PKCS8EncodedKeySpec priKeySpec = new PKCS8EncodedKeySpec(priKeyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        return keyFactory.generatePrivate(priKeySpec);
    }

    /**
     * 得到公钥
     * 
     * @param key 密钥字符串（经过base64编码）
     * @throws Exception
     */
    private static PublicKey getPublicKey(String pubKey) throws Exception {
        byte[] pubkeyBytes = decode(pubKey);
        X509EncodedKeySpec pubKeySpec = new X509EncodedKeySpec(pubkeyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        return keyFactory.generatePublic(pubKeySpec);
    }

    /**
     * Encodes hex octects into Base64
     * 
     * @param binaryData Array containing binaryData
     * @return Encoded Base64 array
     */
    public static String encode(byte[] binaryData) {

        if (binaryData == null) {
            return null;
        }

        int lengthDataBits = binaryData.length * EIGHTBIT;
        if (lengthDataBits == 0) {
            return "";
        }

        int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;
        int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;
        int numberQuartet = fewerThan24bits != 0 ? numberTriplets + 1 : numberTriplets;
        char encodedData[] = null;

        encodedData = new char[numberQuartet * 4];

        byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;

        int encodedIndex = 0;
        int dataIndex = 0;
        if (fDebug) {
            System.out.println("number of triplets = " + numberTriplets);
        }

        for (int i = 0; i < numberTriplets; i++) {
            b1 = binaryData[dataIndex++];
            b2 = binaryData[dataIndex++];
            b3 = binaryData[dataIndex++];

            if (fDebug) {
                System.out.println("b1= " + b1 + ", b2= " + b2 + ", b3= " + b3);
            }

            l = (byte) (b2 & 0x0f);
            k = (byte) (b1 & 0x03);

            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
            byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);
            byte val3 = ((b3 & SIGN) == 0) ? (byte) (b3 >> 6) : (byte) ((b3) >> 6 ^ 0xfc);

            if (fDebug) {
                System.out.println("val2 = " + val2);
                System.out.println("k4   = " + (k << 4));
                System.out.println("vak  = " + (val2 | (k << 4)));
            }

            encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
            encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
            encodedData[encodedIndex++] = lookUpBase64Alphabet[(l << 2) | val3];
            encodedData[encodedIndex++] = lookUpBase64Alphabet[b3 & 0x3f];
        }

        // form integral number of 6-bit groups
        if (fewerThan24bits == EIGHTBIT) {
            b1 = binaryData[dataIndex];
            k = (byte) (b1 & 0x03);
            if (fDebug) {
                System.out.println("b1=" + b1);
                System.out.println("b1<<2 = " + (b1 >> 2));
            }
            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
            encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
            encodedData[encodedIndex++] = lookUpBase64Alphabet[k << 4];
            encodedData[encodedIndex++] = PAD;
            encodedData[encodedIndex++] = PAD;
        } else if (fewerThan24bits == SIXTEENBIT) {
            b1 = binaryData[dataIndex];
            b2 = binaryData[dataIndex + 1];
            l = (byte) (b2 & 0x0f);
            k = (byte) (b1 & 0x03);

            byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
            byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);

            encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
            encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
            encodedData[encodedIndex++] = lookUpBase64Alphabet[l << 2];
            encodedData[encodedIndex++] = PAD;
        }

        return new String(encodedData);
    }

    /**
     * Decodes Base64 data into octects
     * 
     * @param encoded string containing Base64 data
     * @return Array containind decoded data.
     */
    public static byte[] decode(String encoded) {

        if (encoded == null) {
            return null;
        }

        char[] base64Data = encoded.toCharArray();
        // remove white spaces
        int len = removeWhiteSpace(base64Data);

        if (len % FOURBYTE != 0) {
            return null;// should be divisible by four
        }

        int numberQuadruple = (len / FOURBYTE);

        if (numberQuadruple == 0) {
            return new byte[0];
        }

        byte decodedData[] = null;
        byte b1 = 0, b2 = 0, b3 = 0, b4 = 0;
        char d1 = 0, d2 = 0, d3 = 0, d4 = 0;

        int i = 0;
        int encodedIndex = 0;
        int dataIndex = 0;
        decodedData = new byte[(numberQuadruple) * 3];

        for (; i < numberQuadruple - 1; i++) {

            if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))
                    || !isData((d3 = base64Data[dataIndex++]))
                    || !isData((d4 = base64Data[dataIndex++]))) {
                return null;
            } // if found "no data" just return null

            b1 = base64Alphabet[d1];
            b2 = base64Alphabet[d2];
            b3 = base64Alphabet[d3];
            b4 = base64Alphabet[d4];

            decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
            decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
            decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);
        }

        if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))) {
            return null;// if found "no data" just return null
        }

        b1 = base64Alphabet[d1];
        b2 = base64Alphabet[d2];

        d3 = base64Data[dataIndex++];
        d4 = base64Data[dataIndex++];
        if (!isData((d3)) || !isData((d4))) {// Check if they are PAD characters
            if (isPad(d3) && isPad(d4)) {
                if ((b2 & 0xf) != 0)// last 4 bits should be zero
                {
                    return null;
                }
                byte[] tmp = new byte[i * 3 + 1];
                System.arraycopy(decodedData, 0, tmp, 0, i * 3);
                tmp[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
                return tmp;
            } else if (!isPad(d3) && isPad(d4)) {
                b3 = base64Alphabet[d3];
                if ((b3 & 0x3) != 0)// last 2 bits should be zero
                {
                    return null;
                }
                byte[] tmp = new byte[i * 3 + 2];
                System.arraycopy(decodedData, 0, tmp, 0, i * 3);
                tmp[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
                tmp[encodedIndex] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
                return tmp;
            } else {
                return null;
            }
        } else { // No PAD e.g 3cQl
            b3 = base64Alphabet[d3];
            b4 = base64Alphabet[d4];
            decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
            decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
            decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);

        }

        return decodedData;
    }

    /**
     * remove WhiteSpace from MIME containing encoded Base64 data.
     * 
     * @param data the byte array of base64 data (with WS)
     * @return the new length
     */
    private static int removeWhiteSpace(char[] data) {
        if (data == null) {
            return 0;
        }

        // count characters that's not whitespace
        int newSize = 0;
        int len = data.length;
        for (int i = 0; i < len; i++) {
            if (!isWhiteSpace(data[i])) {
                data[newSize++] = data[i];
            }
        }
        return newSize;
    }

    private static boolean isWhiteSpace(char octect) {
        return (octect == 0x20 || octect == 0xd || octect == 0xa || octect == 0x9);
    }

    private static boolean isPad(char octect) {
        return (octect == PAD);
    }

    private static boolean isData(char octect) {
        return (octect < BASELENGTH && base64Alphabet[octect] != -1);
    }

    /**
     * <p>
     * 生成密钥对(公钥和私钥)
     * </p>
     * 
     * @return
     * @throws Exception
     */
    public static Map<String, Object> genKeyPair() throws Exception {
        KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(RSA_ALGORITHM);

        SecureRandom secureRandom = new SecureRandom();
        keyPairGen.initialize(KEY_SIZE, secureRandom);
        KeyPair keyPair = keyPairGen.generateKeyPair();

        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        Map<String, Object> keyMap = new HashMap<String, Object>(2);
        keyMap.put(PUBLIC_RKEY, publicKey);
        keyMap.put(PRIVATE_RKEY, privateKey);
        return keyMap;
    }

    /**
     * <p>
     * 生成密钥对字符串(公钥和私钥)
     * </p>
     * 
     * @return
     * @throws Exception
     */
    public static Map<String, String> genKeyStringPair() throws Exception {
        KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(RSA_ALGORITHM);

        SecureRandom secureRandom = new SecureRandom();
        keyPairGen.initialize(KEY_SIZE, secureRandom);
        KeyPair keyPair = keyPairGen.generateKeyPair();

        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();

        byte[] publicBytes = publicKey.getEncoded();
        String publicKeyString = RSAUtil.encode(publicBytes);

        byte[] privateBytes = privateKey.getEncoded();
        String privateKeyString = RSAUtil.encode(privateBytes);

        Map<String, String> keyMap = new HashMap<String, String>(2);
        keyMap.put(PUBLIC_RKEY, publicKeyString);
        keyMap.put(PRIVATE_RKEY, privateKeyString);
        return keyMap;
    }
}