带签名的小程序使用URLClassLoader加载带签名的jar文件，但存在安全问题

Question

我有一个签名的小程序。为了实现某些插件体系结构，我下载了具有特定类的JAR文件并将其存储到磁盘中。

然后我用加载这些类URLCLassLoader。因此，现在我尝试从已加载的类中调用某些方法，并且遇到了安全问题。

SecurityManager加载类be时似乎无法检查“符号令牌” URLClassLoaded。有人知道如何解决这个问题吗？

非常感谢！

正在加载。

URLClassLoader loader = new URLClassLoader(new URL[] {libraryArchive.toURI().toURL()}, Compress.class.getClassLoader());

调用。

...
org.palettelabs.comm.desktopcapture.pim.Library lib = libraryClass.newInstance();
                final Compress compressingLibrary = (Compress) lib;
                File file = AccessController.doPrivileged(new PrivilegedExceptionAction<File>() {

                    @Override
                    public File run() {
                        try {
                            File file = compressingLibrary.compress(filesList);
                            return file;
                        } catch (Exception e) {
                            Logger.error("applet: compress: invocation external library error", e);
                            return null;
                        }
                    }

                });

例外。

2011-09-16 16:00:08,550 [SwingWorker-pool-1-thread-4] ERROR - applet: compress: invocation external library error
java.security.AccessControlException: access denied (java.io.FilePermission /tmp/dca-palettelabs-storage/test/compress/linux32ffmpeg.jar-extractedFiles/org/palettelabs/
comm/desktopcapture/libs/compress/linux32 read)
        at java.security.AccessControlContext.checkPermission(AccessControlContext.java:374)
        at java.security.AccessController.checkPermission(AccessController.java:546)
        at java.lang.SecurityManager.checkPermission(SecurityManager.java:532)
        at java.lang.SecurityManager.checkRead(SecurityManager.java:871)
        at java.io.File.exists(File.java:731)
        at java.io.File.mkdirs(File.java:1181)
        at org.palettelabs.comm.desktopcapture.pim.Library.extract(Library.java:31)
        at org.palettelabs.comm.desktopcapture.libs.compress.linux32.Linux32.compress(Linux32.java:17)
        at org.palettelabs.comm.desktopcapture.ui.UploadingWorker$1.run(UploadingWorker.java:77)
        at org.palettelabs.comm.desktopcapture.ui.UploadingWorker$1.run(UploadingWorker.java:1)
        at java.security.AccessController.doPrivileged(Native Method)
        at org.palettelabs.comm.desktopcapture.ui.UploadingWorker.compress(UploadingWorker.java:72)
        at org.palettelabs.comm.desktopcapture.ui.UploadingWorker.doInBackground(UploadingWorker.java:57)
        at org.palettelabs.comm.desktopcapture.ui.UploadingWorker.doInBackground(UploadingWorker.java:1)
        at javax.swing.SwingWorker$1.call(SwingWorker.java:277)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
        at java.util.concurrent.FutureTask.run(FutureTask.java:138)
        at javax.swing.SwingWorker.run(SwingWorker.java:316)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
        at java.lang.Thread.run(Thread.java:662)

Answer 1

安装一个自定义的安全管理器，该安全管理器允许来自正确的代码库（程序包等）的代码执行该操作。

为此，请致电System.setSecurityManager(myManager)。（如您所知）myManager是SecurityManager的扩展。

它需要一个受信任的小程序来设置安全管理器。