encryptclasses.java

java类加密保护类

package com.tmri.sourcesafe;
// EncryptClasses.java

import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;

public class EncryptClasses
{
  static public void main( String args[] ) throws Exception {
      EncryptClasses test=new EncryptClasses();
      String _args[]={"key.data","App.class","Foo.class","Bar.class"};

      test.test(_args);
  }
  public void test(String args[])throws Exception
  {
      String keyFilename = args[0];
      String algorithm = "DES";

      // 生成密匙
      SecureRandom sr = new SecureRandom();
      byte rawKey[] = Util.readFile( keyFilename );
      DESKeySpec dks = new DESKeySpec( rawKey );
      SecretKeyFactory keyFactory = SecretKeyFactory.getInstance( algorithm );
      SecretKey key = keyFactory.generateSecret( dks );

      // 创建用于实际加密操作的Cipher对象
      Cipher ecipher = Cipher.getInstance( algorithm );
      ecipher.init( Cipher.ENCRYPT_MODE, key, sr );

      // 加密命令行中指定的每一个类
      for (int i=1; i<args.length; ++i) {
	String filename = args[i];

	// 读入类文件
	byte classData[] = Util.readFile( filename );

	// 加密
	byte encryptedClassData[] = ecipher.doFinal( classData );

	// 保存加密后的内容
	Util.writeFile( filename, encryptedClassData );

	System.out.println( "Encrypted "+filename );
      }

  }
}