App Shielding Error Reporting on Android

If an application shuts down, either due to a crash or a detected security problem, can exit and log a proper stack trace, or open the browser with a predefined URL. That is, unless you have enabled the shutdownImmediately configuration option. Otherwise, the shutdown reason is accessible via Logcat. If the application is installed via Google Play, and the user opts into sharing diagnostic data, the report will also appear in the Google Play Console’s "Crashes & ANRs" page.

The stack trace will have distinct exception classes depending on the reason for the shutdown. By default, however, the stack trace will contain obfuscated class names and look more like the following:

FATAL EXCEPTION:
qmfk.l: 01
    at qmfk.L.a(Unknown Source:112)
    at qmfk.L.b(Unknown Source:12)
    ...

In this example, qmfk.l is the obfuscated App Shielding class. The obfuscated names can be decoded using the ProGuard retrace tool with the mappings.txt file produced during shielding. This mapping file can also be uploaded to Google Play to automatically decode stack traces in the Google Play Console.

To deobfuscate a crash report

• Use the following command:

  retrace.bat | retrace.sh [-verbose] <mappingFile> <crashReport>

  where:

  • mappingFile is the path to the mapping.txt file.

  • crashReport is the path to the crash report to deobfuscate.

The message in the stack trace will include a hex-coded string. In the above example, the message points to "01", which indicates repackaging detection. Other shutdown reasons use different exception classes and message encoding, but the first two characters will always refer to the shutdown reasons described below. If more than two characters are present, App Shielding has encoded other types of information related to the shutdown reason. For further analysis, forward the error message to OneSpan Technical Support.

App Shielding can be configured to not create such stack traces by enabling the Shutdown Immediately configuration option. However, we do not recommend this, since it limits the ability to diagnose problems.

List of error codes for shutdown reasons

If App Shielding shuts down the application and launches a web browser with a preconfigured URL to explain the problem to the user, one of the exit URL variable placeholders is %REASON%. The following %REASON% error codes for the shutdown are possible:

For more information about launching a web browser with a preconfigured URL, see Exit URL Launching on Android.