java RSA 加签验签【转】

引用自: http://blog.csdn.net/wangqiuyun/article/details/42143957/

java RSA 加签验签

package com.testdemo.core.service.impl.alipay;

import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/**
 * RSA签名验签类 http://blog.csdn.net/wangqiuyun/article/details/42143957/
 */
public class RSASignature {

    /**
     * 签名算法
     */
    public static final String SIGN_ALGORITHMS = "SHA1WithRSA";

    /**
     * RSA签名
     *
     * @param content
     *            待签名数据
     * @param privateKey
     *            商户私钥
     * @param encode
     *            字符集编码
     * @return 签名值
     */
    public static String sign(String content, String privateKey, String encode) {
        try {
            PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(new BASE64Decoder().decodeBuffer(privateKey));
            KeyFactory keyf = KeyFactory.getInstance("RSA");
            PrivateKey priKey = keyf.generatePrivate(priPKCS8);
            java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);
            signature.initSign(priKey);
            signature.update(content.getBytes(encode));
            byte[] signed = signature.sign();
            return new BASE64Encoder().encode(signed);
        } catch (Exception e) {
            e.printStackTrace();
        }

        return null;
    }

    public static String sign(String content, String privateKey) {
        try {
            PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(new BASE64Decoder().decodeBuffer(privateKey));
            KeyFactory keyf = KeyFactory.getInstance("RSA");
            PrivateKey priKey = keyf.generatePrivate(priPKCS8);
            java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);
            signature.initSign(priKey);
            signature.update(content.getBytes());
            byte[] signed = signature.sign();
            return new BASE64Encoder().encode(signed);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * RSA验签名检查
     *
     * @param content
     *            待签名数据
     * @param sign
     *            签名值
     * @param publicKey
     *            分配给开发商公钥
     * @param encode
     *            字符集编码
     * @return 布尔值
     */
    public static boolean doCheck(String content, String sign, String publicKey, String encode) {
        try {
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            byte[] encodedKey = new BASE64Decoder().decodeBuffer(publicKey);
            PublicKey pubKey = keyFactory.generatePublic(new X509EncodedKeySpec(encodedKey));

            java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);

            signature.initVerify(pubKey);
            signature.update(content.getBytes(encode));

            boolean bverify = signature.verify(new BASE64Decoder().decodeBuffer(sign));
            return bverify;

        } catch (Exception e) {
            e.printStackTrace();
        }

        return false;
    }

    public static boolean doCheck(String content, String sign, String publicKey) {
        try {
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            byte[] encodedKey = new BASE64Decoder().decodeBuffer(publicKey);
            PublicKey pubKey = keyFactory.generatePublic(new X509EncodedKeySpec(encodedKey));

            java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);

            signature.initVerify(pubKey);
            signature.update(content.getBytes());

            boolean bverify = signature.verify(new BASE64Decoder().decodeBuffer(sign));
            return bverify;

        } catch (Exception e) {
            e.printStackTrace();
        }

        return false;
    }

}