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;

    }

}