package jct;import java.security.KeyFactory;import java.security.PrivateKey;import java.security.PublicKey;import java.security.Signature;import java.security.KeyPair;import java.security.KeyPairGenerator;import java.security.SecureRandom;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;import java.security.Security;import javax.crypto.Cipher;/** * <p>封裝同RSA非對稱加密算法有關的方法，可用于數(shù)字簽名，RSA加密解密</p> * @Copyright:WDSsoft * @ad:WDSsoft “企業(yè)多級數(shù)字簽名系統(tǒng)”- 最佳的企業(yè)電子文檔多級數(shù)字簽名方案 * @URL:www.wdssoft.com * @作者 吳東升 mdss@wdssoft.com bluesunday@sohu.com */public class RSATool {  public RSATool() {  }  /**   * 用一個已打包成byte[]形式的私鑰加密數(shù)據(jù)，即數(shù)字簽名   * @param keyInByte 打包成byte[]的私鑰   * @param source 要簽名的數(shù)據(jù)，一般應是數(shù)字摘要   * @return 簽名 byte[]   */  public static byte[] sign(byte[] keyInByte,byte[] source){   try{      PKCS8EncodedKeySpec priv_spec=new PKCS8EncodedKeySpec(keyInByte);      KeyFactory mykeyFactory=KeyFactory.getInstance("RSA");      PrivateKey privKey= mykeyFactory.generatePrivate(priv_spec);      Signature sig=Signature.getInstance("SHA1withRSA");      sig.initSign(privKey);      sig.update(source);      return sig.sign();   }catch(Exception e){   return null;      }  }  /**   * 驗證數(shù)字簽名   * @param keyInByte 打包成byte[]形式的公鑰   * @param source 原文的數(shù)字摘要   * @param sign 簽名（對原文的數(shù)字摘要的簽名）   * @return 是否證實 boolean   */  public static boolean verify(byte[] keyInByte,byte[] source,byte[] sign){        try{          KeyFactory mykeyFactory=KeyFactory.getInstance("RSA");          Signature sig=Signature.getInstance("SHA1withRSA");          X509EncodedKeySpec pub_spec=new X509EncodedKeySpec(keyInByte);          PublicKey pubKey=mykeyFactory.generatePublic(pub_spec);          sig.initVerify(pubKey);          sig.update(source);          return sig.verify(sign);        }catch(Exception e){             return false;           }        }  /**   * 建立新的密鑰對，返回打包的byte[]形式私鑰和公鑰   * @return 包含打包成byte[]形式的私鑰和公鑰的object[],其中，object[0]為私鑰byte[],object[1]為工要byte[]   */  public static Object[] giveRSAKeyPairInByte(){        KeyPair newKeyPair=creatmyKey();        if(newKeyPair==null)return null;        Object[] re=new Object[2];        if(newKeyPair!=null){           PrivateKey priv=newKeyPair.getPrivate();           byte[] b_priv = priv.getEncoded();           PublicKey pub=newKeyPair.getPublic();           byte[] b_pub=pub.getEncoded();                   re[0]=b_priv;                   re[1]=b_pub;                   return re;        }        return null;      }    /**         * 新建密鑰對         * @return KeyPair對象         */      public static KeyPair creatmyKey(){            KeyPair myPair;            long mySeed;            mySeed=System.currentTimeMillis();            try{                  KeyPairGenerator keyGen=KeyPairGenerator.getInstance("RSA");                  SecureRandom random=SecureRandom.getInstance("SHA1PRNG","SUN");                  random.setSeed(mySeed);                  keyGen.initialize(1024,random);                  myPair=keyGen.generateKeyPair();                  }catch(Exception e1){  return null;  }             return myPair;      }/** * 使用RSA公鑰加密數(shù)據(jù) * @param pubKeyInByte 打包的byte[]形式公鑰 * @param data 要加密的數(shù)據(jù) * @return 加密數(shù)據(jù) */  public static byte[] encryptByRSA(byte[] pubKeyInByte,byte[] data){    try{          KeyFactory mykeyFactory=KeyFactory.getInstance("RSA");          X509EncodedKeySpec pub_spec=new X509EncodedKeySpec(pubKeyInByte);          PublicKey pubKey=mykeyFactory.generatePublic(pub_spec);          Cipher cipher=Cipher.getInstance("RSA/ECB/PKCS1Padding");          cipher.init(Cipher.ENCRYPT_MODE,pubKey);          return cipher.doFinal(data);    }catch(Exception e){  return null; }  } /**  * 用RSA私鑰解密  * @param privKeyInByte 私鑰打包成byte[]形式  * @param data 要解密的數(shù)據(jù)  * @return 解密數(shù)據(jù)  */  public static byte[] decryptByRSA(byte[] privKeyInByte,byte[] data){   try{          PKCS8EncodedKeySpec priv_spec=new PKCS8EncodedKeySpec(privKeyInByte);          KeyFactory mykeyFactory=KeyFactory.getInstance("RSA");          PrivateKey privKey= mykeyFactory.generatePrivate(priv_spec);          Cipher cipher=Cipher.getInstance("RSA/ECB/PKCS1Padding");          cipher.init(Cipher.DECRYPT_MODE,privKey);          return cipher.doFinal(data);        }catch(Exception e){  return null;     }  }/** *測試 */   public static void main(String[] args) {         try{               Object[]  v=giveRSAKeyPairInByte();               byte[] source=Digest.MdigestSHA("haha");               byte[] sign=sign((byte[])v[0],source);               boolean yes=verify((byte[])v[1],source,sign);               if(yes) System.out.print("verify\n");               }catch(Exception e){e.printStackTrace();}   }}