2

I am currently debugging the EXT4 loader, and using the GUI and selecting the file every time is fairly annoying. The simpler solution would be to have a Headless Analyzer invocation that imports the file system image and parses it.

The naive way of simply calling the Headless Analyzer with the arguments for the project location, name and -import image.ext4 results in the following errors:

INFO  No load spec found for import file: <redacted>.ext4   (AutoImporter.java:215) 
ERROR The AutoImporter could not successfully load <redacted>.ext4 with the provided import parameters. Please ensure that any specified processor/cspec arguments are compatible with the loader that is used during import and try again.   (HeadlessAnalyzer.java:1651) 
ERROR REPORT: Import failed for file: <redacted>.ext4   (HeadlessAnalyzer.java:1688) 

The documentation only covers handling specific binaries, so this doesn't seem like it is supported currently.

A workaround that does not work for my specific use case, but might suffice for others is to mount the image and then use the -recursive argument for the Headless Analyzer.

A solution could be a script, which would call whatever is called after selecting a file via the Open File System menu option. There doesn't seem to be one like this shipped with Ghidra yet, but maybe there is one written by the community somewhere.

1

The solution that I found that suffices for my current issue of debugging the EXT4 parser is is the following Ghidra Script, saved as ImportFS.java:

import ghidra.app.script.GhidraScript;
import ghidra.formats.gfilesystem.FSRL;
import ghidra.formats.gfilesystem.FileSystemRef;
import ghidra.formats.gfilesystem.FileSystemService;

import java.io.File;

public class ImportFS extends GhidraScript{

        @Override
        protected void run()throws Exception{
                File filesystemImage = askFile("Choose Filesystem Container", "Select");
                FSRL fsrl = FSRL.fromString("file://" + filesystemImage.getAbsolutePath());
                FileSystemService fileSystemService = FileSystemService.getInstance();
                FileSystemRef ref = fileSystemService.probeFileForFilesystem(fsrl, monitor, null);
        }
}

And invoking the Headless Analyzer with

analyzeHeadless /tmp temp_project -scriptPath /path/to/script/folder -readOnly -preScript ImportFS.java /path/to/file.img

askFile will not prompt for the file via a GUI when running in headless mode, so either /path/to/file.img has to be provided via the argument or a property file.

Further code would be needed for actually importing the file system tree after parsing, but this should be doable.

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