[iOS] frida string 확인

Interceptor.attach(ObjC.classes.NSString['+ stringWithUTF8String:'].implementation, {
    onEnter: function (args) {
      console.log('[+] Hooked +[NSString stringWithUTF8String:] ');
    },
    onLeave: function (retval) {
      var str = new ObjC.Object(ptr(retval)).toString()
      
      console.log("\nBacktrace:\n" + Thread.backtrace(this.context, Backtracer.ACCURATE).map(DebugSymbol.fromAddress).join("\n"));
      console.log('[+] Returning [NSString stringWithUTF8String:] -> ', str);
      return retval;
    }
});

https://github.com/frida/frida/issues/607