Error enumerating loaded classes (9.1.14)

[SrFlipFlop]

Hi,

I'm trying to enumerate loaded classes using Android 5.0.1 emulator with the following script:
if (Java.available) { Java.enumerateLoadedClasses({ onMatch: function(className) { send(className); } }); } else { send("Not available Java"); }

Using Frida 9.1.7 it give me the following error:
{u'columnNumber': 1, u'description': u'Error: Enumerating loaded classes is only supported on Dalvik for now', u'fileName': u'frida/node_modules/frida-java/index.js', u'lineNumber': 87, u'type': u'error', u'stack': u'Error: Enumerating loaded classes is only supported on Dalvik for now\n at c (frida/node_modules/frida-java/index.js:87)\n at frida/node_modules/frida-java/index.js:143\n at script1.js:7'}

Seeing that the above error had already been notified, I try a newer Frida versions (9.1.14 and 9.1.13) and it give me a different error:
{u'columnNumber': 1, u'description': u'Error: VM::GetEnv failed: -2', u'fileName': u'frida/node_modules/frida-java/lib/result.js', u'lineNumber': 7, u'type': u'error', u'stack': u'Error: VM::GetEnv failed: -2\n at e (frida/node_modules/frida-java/lib/result.js:7)\n at frida/node_modules/frida-java/lib/vm.js:53\n at h (frida/node_modules/frida-java/index.js:166)\n at frida/node_modules/frida-java/index.js:105\n at script1.js:7'}

To discard that the error was provoked by the Android version, I also tried to use Android 6.0 but the same error message was disclosed.emulator and have the same error.

I hope that all the information help you to find the error more quickly. Thanks for the great open source project that is Frida.

Ferran Obiols.

[oleavr]

Thanks for reporting. The issue here is that it is forbidden to call any Java APIs outside of Java.perform(). Please ensure your Java.enumerateLoadedClasses() call happens inside a Java.perform(). Cheers!

[SrFlipFlop]

Thanks, with this correction my script works correctly.