script/frida-learn/game_js/hook_signatures.js

setImmediate(function(){
    Java.perform(function(){
        send("starting script");
        var ApplicationPackageManager = Java.use("android.app.ApplicationPackageManager");
        var PackageInfo = Java.use("android.content.pm.PackageInfo");
        var Signature = Java.use("android.content.pm.Signature");
        var Array = Java.use("java.lang.reflect.Array");
        ApplicationPackageManager.getPackageInfo.overload("java.lang.String","int").implementation = function(var1,var2){
            var result = this.getPackageInfo(var1,var2);
            if(var2 == 64){
                send("getPackageInfo----> var2:"+var2);
                console.log(Java.use("android.util.Log").getStackTraceString(Java.use("java.lang.Exception").$new()));
            }

            return result;
        };
        Signature.toByteArray.overload().implementation = function(){
            var result = this.toByteArray();
            console.log("yb sign byte[]------->",result);
            var signCharStr = Signature.$new(result).toCharsString()
            console.log("yb sign charStr------->",signCharStr);
            return result;
        }

    });
});