refactor: Unify startup scripts

Previously we had three different startup scripts:
- The docker entrypoint (fact_extractor/docker_extract.py)
- The python module entrypoint (fact_extractor/fact_extract.py)
- The docker wrapper (extract.py)
This commit removes the docker entrypoint and moves the module entrypoint
to __main__.py while changing as little code as possible.

This commit removes two usages of `sudo` that were used to chown
the extracted files.
Using sudo in a python module is bad practice.
Also, one could argue that the --chown functionality
should be replaced by proper container namespace mapping
as its usecase is to change back permissions from root to
the user that called docker.

Dockerfile

@@ -17,10 +17,10 @@ RUN --mount=type=cache,target=/var/cache/apt \
     --mount=type=cache,target=/root/.cache/pip \
 /app/fact_extractor/install/pre_install.sh
 
-ADD . /app
+ADD . /app/
 RUN --mount=type=cache,target=/var/cache/apt \
     --mount=type=cache,target=/root/.cache/pip \
 /app/install.py
 
 
-ENTRYPOINT ["/app/fact_extractor/docker_extraction.py"]
+ENTRYPOINT ["/app/docker/entrypoint.py"]

README.md

@@ -42,7 +42,7 @@ sudo apt install linux-modules-extra-$(uname -r)
 The tool can then be run with
 
 ```bash
-fact_extractor/fact_extract.py [OPTIONS] PATH_TO_FIRMWARE
+python -m fact_extractor [OPTIONS] PATH_TO_FIRMWARE
 ```
 The tool is build with docker in mind.
 To that end it extracts all files into a directory specified in the config.

docker/entrypoint.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+python -m fact_extractor \
+    --config_file /app/config/main.cfg \
+    "$@"

extract.py

@@ -18,7 +18,10 @@
 
 def parse_arguments():
     parser = argparse.ArgumentParser(
-        description='Command line interface for FACT_extractor.\nExtract arbitrary container or compression formats with one utility.'
+        description=(
+            'Command line wrapper for FACT_extractor docker container.\n'
+            ' Extract arbitrary container or compression formats with one utility.'
+        )
     )
     parser.add_argument('-v', '--version', action='version', version=set_version())
     parser.add_argument('-c', '--container', help='docker container', default=DEFAULT_CONTAINER)

fact_extractor/fact_extract.py → fact_extractor/__main__.py

@@ -20,22 +20,29 @@
 import sys
 from pathlib import Path
 
-from fact_extractor.helperFunctions.program_setup import setup_argparser, setup_logging, load_config
+from fact_extractor.helperFunctions.file_system import change_owner_of_output_files
+from fact_extractor.helperFunctions.program_setup import setup_argparser, setup_logging, load_config, check_ulimits
 from fact_extractor.unpacker.unpack import unpack
 
 
 def main():
     arguments = setup_argparser('FACT extractor', 'Standalone extraction utility', sys.argv)
     config = load_config(arguments.config_file)
     setup_logging(arguments.debug, log_file=arguments.log_file, log_level=arguments.log_level)
+    check_ulimits()
+
+    data_dir = Path(config.get('unpack', 'data_folder'))
+    report_dir = data_dir / 'reports'
+    files_dir = data_dir / 'files'
 
     # Make sure report folder exists some meta.json can be written
-    report_folder = Path(config.get('unpack', 'data_folder'), 'reports')
-    report_folder.mkdir(parents=True, exist_ok=True)
+    report_dir.mkdir(parents=True, exist_ok=True)
+
     unpack(arguments.FILE_PATH, config)
 
-    return 0
+    if arguments.chown is not None:
+        change_owner_of_output_files(files_dir, arguments.chown)
 
+    return 0
 
-if __name__ == '__main__':
-    exit(main())
+sys.exit(main())

fact_extractor/helperFunctions/file_system.py

@@ -54,8 +54,8 @@ def change_owner_of_output_files(files_dir: Path, owner: str) -> int:
         logging.error('ownership string should have the format <user id>:<group id>')
         return 1
 
-    _, return_code_chown = execute_shell_command_get_return_code(f'sudo chown -R {owner} {files_dir}')
-    _, return_code_chmod = execute_shell_command_get_return_code(f'sudo chmod -R u+rw {files_dir}')
+    _, return_code_chown = execute_shell_command_get_return_code(f'chown -R {owner} {files_dir}')
+    _, return_code_chmod = execute_shell_command_get_return_code(f'chmod -R u+rw {files_dir}')
     return return_code_chmod | return_code_chown
 
 

fact_extractor/helperFunctions/program_setup.py

@@ -10,7 +10,7 @@
 
 
 def setup_argparser(name, description, command_line_options, version=__VERSION__):
-    parser = argparse.ArgumentParser(description='{} - {}'.format(name, description))
+    parser = argparse.ArgumentParser(prog=name, description='{} - {}'.format(name, description))
     parser.add_argument('-V', '--version', action='version', version='{} {}'.format(name, version))
     parser.add_argument('-l', '--log_file', help='path to log file', default=None)
     parser.add_argument('-L', '--log_level', help='define the log level', choices=['DEBUG', 'INFO', 'WARNING', 'ERROR'], default=None)

fact_extractor/unpacker/unpackBase.py

@@ -102,7 +102,7 @@ def _extract_files_from_file_using_specific_unpacker(self, file_path: str, tmp_d
         return out, meta_data
 
     def change_owner_back_to_me(self, directory: str = None, permissions: str = 'u+r'):
-        with Popen(f'sudo chown -R {getuid()}:{getgid()} {directory}', shell=True, stdout=PIPE, stderr=PIPE) as pl:
+        with Popen(f'chown -R {getuid()}:{getgid()} {directory}', shell=True, stdout=PIPE, stderr=PIPE) as pl:
             pl.communicate()
         self.grant_read_permission(directory, permissions)