bcv-vf/plugins/example/ExampleStringDecrypter.js

/**
 * This is an example of a string decrypter plugin
 */

var PluginConsole = Java.type("the.bytecode.club.bytecodeviewer.api.PluginConsole");
var MultipleChoiceDialogue = Java.type("the.bytecode.club.bytecodeviewer.gui.components.MultipleChoiceDialogue")
var BytecodeViewer = Java.type("the.bytecode.club.bytecodeviewer.api.BCV")

var dialogue = new MultipleChoiceDialogue("Bytecode Viewer - WARNING",
                "WARNING: This will load the classes into the JVM and execute the initialize function"
                        + "\nfor each class. IF THE FILE YOU'RE LOADING IS MALICIOUS, DO NOT CONTINUE.",
                ["Continue", "Cancel"]);
var gui = new PluginConsole("Skeleton");

function execute(classNodeList)
{
    if(dialogue.promptChoice() == 0)
    {
        var needsWarning = false;

        for (cnIndex = 0; cnIndex < classNodeList.length; cnIndex++)
        {
            try
            {
                var cn = classNodeList[cnIndex];
                var fields = cn.fields.toArray();

                //load the class node into the classloader
                BytecodeViewer.loadClassIntoClassLoader(cn);

                for (fieldIndex = 0; fieldIndex < fields.length; fieldIndex++)
                {
                    var field = fields[fieldIndex];

                    //if the class contains the field z, get the class object from the class node
                    //then print out the value of the fields inside the class
                    //if the strings get decrypted on init, this allows you to dump the current values

                    if(field.name.equals("z")) {// && f.desc.equals("([Ljava/lang/String;)V")) {
                        try
                        {
                            var loadedClass = BytecodeViewer.getClassNodeLoader().nodeToClass(cn);
                            var reflectedFields = loadedClass.getFields();

                            for (reflectedFieldIndex = 0; reflectedFieldIndex < reflectedFields.length; reflectedFieldIndex++)
                            {
                                var reflectedField = reflectedFields[fieldIndex];
                                var s = reflectedField.get(null);

                                if(s != null && !s.empty())
                                    gui.appendText(cn + "->" + s);
                            }
                        } catch(e) {}
                    }
                }
            }
            catch(e)
            {
                gui.appendText("Failed loading class " + cn.getName());
                e.printStackTrace();
                needsWarning = true;
            }
        }

        if (needsWarning)
        {
            BytecodeViewer.showMessage("Some classes failed to decrypt, if you'd like to decrypt all of them"
                    + nl + "makes sure you include ALL the libraries it requires.");
        }

        gui.setVisible(true);
    }
}