RSA/RSA2 进行签名和验签

 package com.byttersoft.hibernate.erp.szmy.util;

 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.Reader;
 import java.io.StringWriter;
 import java.io.Writer;
 import java.security.KeyFactory;
 import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.security.spec.PKCS8EncodedKeySpec;
 import java.security.spec.X509EncodedKeySpec;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;

 import org.apache.commons.codec.binary.Base64;

 import com.byttersoft.framework.util.StringUtil;
 /**
  * RSA的签名及验签
  * @author zhouyy
  *
  */
 public class RSA {

     private static final String SIGN_TYPE_RSA = "RSA";

     private static final String SIGN_TYPE_RSA2 = "RSA2";

     private static final String SIGN_ALGORITHMS = "SHA1WithRSA";

     private static final String SIGN_SHA256RSA_ALGORITHMS = "SHA256WithRSA";

     private static final int DEFAULT_BUFFER_SIZE = 8192;

     /**
      * RSA/RSA2 生成签名
      *
      * @param map
      *            包含 sign_type、privateKey、charset
      * @return
      * @throws Exception
      */
     public static String rsaSign(Map map) throws Exception {
         PrivateKey priKey = null;
         java.security.Signature signature = null;
         String signType = map.get("sign_type").toString();
         String privateKey = map.get("privateKey").toString();
         String charset = map.get("charset").toString();
         String content = getSignContent(map);
         map.put("content", content);
         System.out.println("请求参数生成的字符串为:" + content);
         if (SIGN_TYPE_RSA.equals(signType)) {
             priKey = getPrivateKeyFromPKCS8(SIGN_TYPE_RSA, new ByteArrayInputStream(privateKey.getBytes()));
             signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);
         } else if (SIGN_TYPE_RSA2.equals(signType)) {
             priKey = getPrivateKeyFromPKCS8(SIGN_TYPE_RSA, new ByteArrayInputStream(privateKey.getBytes()));
             signature = java.security.Signature.getInstance(SIGN_SHA256RSA_ALGORITHMS);
         } else {
             throw new Exception("不是支持的签名类型 : : signType=" + signType);
         }
         signature.initSign(priKey);

         if (StringUtil.isEmpty(charset)) {
             signature.update(content.getBytes());
         } else {
             signature.update(content.getBytes(charset));
         }

         byte[] signed = signature.sign();

         return new String(Base64.encodeBase64(signed));

     }

     /**
      * 验签方法
      *
      * @param content
      *            参数的合成字符串格式: key1=value1&key2=value2&key3=value3...
      * @param sign
      * @param publicKey
      * @param charset
      * @param signType
      * @return
      */
     public static boolean rsaCheck(Map map, String sign) throws Exception {
         java.security.Signature signature = null;
         String signType = map.get("sign_type").toString();
         String privateKey = map.get("privateKey").toString();
         String charset = map.get("charset").toString();
         String content = map.get("content").toString();
         String publicKey = map.get("publicKey").toString();
         System.out.println(">>验证的签名为:" + sign);
         System.out.println(">>生成签名的参数为:" + content);
         PublicKey pubKey = getPublicKeyFromX509("RSA", new ByteArrayInputStream(publicKey.getBytes()));
         if (SIGN_TYPE_RSA.equals(signType)) {
             signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);
         } else if (SIGN_TYPE_RSA2.equals(signType)) {
             signature = java.security.Signature.getInstance(SIGN_SHA256RSA_ALGORITHMS);
         } else {
             throw new Exception("不是支持的签名类型 : signType=" + signType);
         }
         signature.initVerify(pubKey);

         if (StringUtil.isEmpty(charset)) {
             signature.update(content.getBytes());
         } else {
             signature.update(content.getBytes(charset));
         }

         return signature.verify(Base64.decodeBase64(sign.getBytes()));
     }

     public static PrivateKey getPrivateKeyFromPKCS8(String algorithm, InputStream ins) throws Exception {
         if (ins == null || StringUtil.isEmpty(algorithm)) {
             return null;
         }

         KeyFactory keyFactory = KeyFactory.getInstance(algorithm);

         byte[] encodedKey = readText(ins).getBytes();

         encodedKey = Base64.decodeBase64(encodedKey);

         return keyFactory.generatePrivate(new PKCS8EncodedKeySpec(encodedKey));
     }

     public static PublicKey getPublicKeyFromX509(String algorithm, InputStream ins) throws Exception {
         KeyFactory keyFactory = KeyFactory.getInstance(algorithm);

         StringWriter writer = new StringWriter();
         io(new InputStreamReader(ins), writer, -1);

         byte[] encodedKey = writer.toString().getBytes();

         encodedKey = Base64.decodeBase64(encodedKey);

         return keyFactory.generatePublic(new X509EncodedKeySpec(encodedKey));
     }

     /**
      * 把参数合成成字符串
      *
      * @param sortedParams
      * @return
      */
     public static String getSignContent(Map<String, String> sortedParams) {
         StringBuffer content = new StringBuffer();
         // app_id,method,charset,sign_type,version,bill_type,timestamp,bill_date
         String[] sign_param = sortedParams.get("sign_param").split(",");// 生成签名所需的参数
         List<String> keys = new ArrayList<String>();
         for (int i = 0; i < sign_param.length; i++) {
             keys.add(sign_param[i]);
         }
         Collections.sort(keys);
         int index = 0;
         for (int i = 0; i < keys.size(); i++) {
             String key = keys.get(i);
             /*if ("biz_content".equals(key)) {
                 content.append(
                         (index == 0 ? "" : "&") + key + "={\"bill_date\":\"" + sortedParams.get("bill_date") + "\",")
                         .append("\"bill_type\":\"" + sortedParams.get("bill_type") + "\"}");
                 index++;
             } else {*/
             String value = sortedParams.get(key);
             if (StringUtil.isNotEmpty(key) && StringUtil.isNotEmpty(value)) {
                 content.append((index == 0 ? "" : "&") + key + "=" + value);
                 index++;
             }
 //            }
         }
         return content.toString();
     }

     private static String readText(InputStream ins) throws IOException {
         Reader reader = new InputStreamReader(ins);
         StringWriter writer = new StringWriter();

         io(reader, writer, -1);
         return writer.toString();
     }

     private static void io(Reader in, Writer out, int bufferSize) throws IOException {
         if (bufferSize == -1) {
             bufferSize = DEFAULT_BUFFER_SIZE >> 1;
         }

         char[] buffer = new char[bufferSize];
         int amount;

         while ((amount = in.read(buffer)) >= 0) {
             out.write(buffer, 0, amount);
         }
     }

 }