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I have an APK that has assemblies in a single blob file. I could extract them successfully using decompress-assemblies.
Is there anyway I can compress them again into assemblies.blob file or at least modify the APK to allow loading the the extracted DLL like older Xamarin APKs?
I seem to have found that the application checks for application_config.have_assembly_store value, if it's true, it only continues if there's an assembly blob. Any idea how to change this value inside the APK?
For unpacking and repacking Xamarin assemblies.blob + assemblies.manifest files you can use the Python based tool Xamarin AssemblyStore Explorer (pyxamstore).
Make sure your current directory contains the files assemblies.blob and assemblies.manifest.
pyxamstore unpack
This will create the directory out which will contain the decoded dll files.
Enter the directory where you have execute pyxamstore unpack and execute
pyxamstore pack
This will generate the two files assemblies.blob.new and assemblies.manifest.new. Just rename the two files to it's original names without .new and replace them in the APK file.
Finally don't forget to zipalign and resign (apksigner) your APK file.
