Move development documentation under docs/development

The Development section holds more than one page and will grow further,
so give it its own directory. development.md becomes development/index.md,
which keeps its published URL, and the custom CLI command page moves
alongside it.

Update the nav, the cross-link between the two pages, and the README
link to the custom command documentation, which is now published at
/development/custom_commands/.

README.md

@@ -84,7 +84,7 @@ details.
 
 Users can also add top-level commands to `mvt-ios` and `mvt-android` from
 installed Python packages or local files and folders. See the
-[custom CLI command documentation](https://docs.mvt.re/en/latest/custom_commands/)
+[custom CLI command documentation](https://docs.mvt.re/en/latest/development/custom_commands/)
 for the plugin entry points and `--load-command` interface.
 
 

docs/development/custom_commands.md

@@ -1,7 +1,7 @@
 # Custom CLI Commands
 
 MVT can load additional top-level commands into `mvt-ios` and `mvt-android`.
-Custom commands are different from [custom forensic modules](development.md#custom-modules):
+Custom commands are different from [custom forensic modules](index.md#custom-modules):
 commands add new CLI operations, while modules add analysis steps to existing
 `check-*` commands.
 

docs/development/index.md

@@ -117,6 +117,93 @@ class DependentCustomModule(MVTModule):
         self.results = [{"manifest_entries": len(manifest_results)}]
 ```
 
+## Installed module packages
+
+Python packages can register modules so they load automatically in every
+module-running `check-*` command, without `--load-module` or
+`MVT_CUSTOM_MODULES`. Register an entry point in the `mvt.modules` group in
+the package's `pyproject.toml`:
+
+```toml
+[project.entry-points."mvt.modules"]
+mvt-plugin-amnesty-custom = "mvt_plugin_amnesty_custom:get_modules"
+```
+
+The entry point must resolve to an iterable of `MVTModule` subclasses, or to
+a callable returning one:
+
+```python
+from mvt.common.module import MVTModule
+
+
+class PackagedModule(MVTModule):
+    supported_commands = (("ios", "check-backup"),)
+
+    def run(self):
+        self.results = [{"message": "packaged module ran"}]
+
+
+def get_modules() -> list[type[MVTModule]]:
+    return [PackagedModule]
+```
+
+Installed modules follow the same rules as other custom modules: each module
+must declare `supported_commands`, and dependencies are resolved with the
+standard ordering logic. A broken entry point is skipped with a warning and
+does not prevent MVT from running. As with custom commands, installed module
+packages run as trusted code inside the MVT process, so install only packages
+from sources you trust.
+
+For a `pipx` installation of MVT, inject the package into MVT's environment:
+
+```bash
+pipx inject mvt mvt-plugin-amnesty-custom
+```
+
+### Naming module packages
+
+Name module packages `mvt-plugin-<name>` (import package `mvt_plugin_<name>`),
+and include the name of the publishing organization or author so packages from
+different groups do not collide: for example, Amnesty International's custom
+modules would be distributed as `mvt-plugin-amnesty-custom` with the import
+package `mvt_plugin_amnesty_custom`.
+
+The prefix makes module packages easy to find on PyPI and keeps their import
+names from clashing with unrelated Python packages. It is a convention, not a
+technical requirement: modules load through the `mvt.modules` entry point
+regardless of what the package is called, and existing packages with other
+names keep working. Note that the prefix is also not a mark of authenticity —
+anyone can publish a package with any available name, so vet a module package
+and its publisher before installing it, whatever it is called.
+
+### Module logging
+
+Modules log through `self.log`, and MVT names the logger for where the module
+came from. MVT's own modules log under their dotted path (for example
+`mvt.ios.modules.mixed.whatsapp`). Everything external is namespaced under
+`mvt.ext` to keep it visually distinct from built-in modules and isolated from
+MVT's internal logger tree:
+
+- Installed packages log under `mvt.ext.<package>`, with the `mvt_plugin_`
+  prefix stripped: modules in `mvt_plugin_amnesty_custom` log as
+  `mvt.ext.amnesty_custom.*`.
+- Files loaded with `--load-module` or `MVT_CUSTOM_MODULES` log as
+  `mvt.ext.<file name>`.
+
+## Auditing loaded modules
+
+Because installed module packages load automatically, MVT records where every
+module came from:
+
+- `--list-modules` groups the available modules by source: MVT itself
+  (with its version), each installed package (with its version and, when
+  installed directly from a repository, the commit), and each file loaded
+  with `--load-module` or `MVT_CUSTOM_MODULES` (with the SHA-256 hash of the
+  file).
+- When a command runs with an `--output` folder, the `command.log` file
+  records one line per module source with the source's version or hash and
+  the list of modules loaded from it.
+
 ## Profiling
 
 Some MVT modules extract and process significant amounts of data during the analysis process or while checking results against known indicators. Care must be

mkdocs.yml

@@ -31,7 +31,6 @@ nav:
     - Introduction: "introduction.md"
     - Installation: "install.md"
     - Command Completion: "command_completion.md"
-    - Custom CLI Commands: "custom_commands.md"
     - Using Docker: "docker.md"
     - MVT for iOS:
         - iOS Forensic Methodology: "ios/methodology.md"
@@ -50,5 +49,7 @@ nav:
         - Check an Android Backup (SMS messages): "android/backup.md"
         - Check Android Intrusion Logs: "android/intrusion_logs.md"
     - Indicators of Compromise: "iocs.md"
-    - Development: "development.md"
+    - Development:
+        - Development Instructions: "development/index.md"
+        - Custom CLI Commands: "development/custom_commands.md"
     - License: "license.md"

src/mvt/common/cmd_check_iocs.py

@@ -9,6 +9,7 @@ from typing import Optional
 
 from mvt.common.command import Command
 from mvt.common.module import MVTModule
+from mvt.common.module_loader import get_module_logger
 from mvt.common.utils import exec_or_profile
 
 log = logging.getLogger(__name__)
@@ -76,7 +77,7 @@ class CmdCheckIOCS(Command):
                 )
 
                 m = iocs_module.from_json(
-                    file_path, log=logging.getLogger(iocs_module.__module__)
+                    file_path, log=get_module_logger(iocs_module)
                 )
                 if not m:
                     log.warning("No result from this module, skipping it")

src/mvt/common/command.py

@@ -19,7 +19,12 @@ from .alerts import AlertLevel, AlertStore
 from .config import settings
 from .indicators import Indicators
 from .module import EncryptedBackupError, MVTModule, run_module, save_timeline
-from .module_loader import module_supports_command
+from .module_loader import (
+    ModuleOrigin,
+    get_module_logger,
+    get_module_origin,
+    module_supports_command,
+)
 from .module_types import ModuleTimeline, URLResult
 from .utils import (
     CustomJSONEncoder,
@@ -210,10 +215,34 @@ class Command:
         for file in generate_hashes_from_path(self.target_path, self.log):
             self.hash_values.append(file)
 
+    @staticmethod
+    def _modules_by_origin(
+        modules: list[type[MVTModule]],
+    ) -> dict[ModuleOrigin, list[str]]:
+        origins: dict[ModuleOrigin, list[str]] = {}
+        for module in modules:
+            origins.setdefault(get_module_origin(module), []).append(module.__name__)
+        return origins
+
     def list_modules(self) -> None:
         self.log.info("Following is the list of available %s modules:", self.name)
-        for module in self._available_modules():
+        for origin, module_names in self._modules_by_origin(
-            self.log.info(" - %s", module.__name__)
+            self._available_modules()
+        ).items():
+            self.log.info(
+                " - Modules from %s: %s", origin.label, ", ".join(module_names)
+            )
+
+    def _log_loaded_modules(self, modules: list[type[MVTModule]]) -> None:
+        """Record the loaded modules and their origins for auditability."""
+        for origin, module_names in self._modules_by_origin(modules).items():
+            self.log.info(
+                "Loaded %d %s modules from %s: %s",
+                len(module_names),
+                self.name,
+                origin.label,
+                ", ".join(module_names),
+            )
 
     def _available_modules(self) -> list[type[MVTModule]]:
         modules = list(self.modules)
@@ -360,6 +389,8 @@ class Command:
         if ordered_modules is None:
             return
 
+        self._log_loaded_modules(ordered_modules)
+
         try:
             self.init()
         except NotImplementedError:
@@ -368,7 +399,7 @@ class Command:
         executed_by_type: dict[type[MVTModule], MVTModule] = {}
         for module in ordered_modules:
 
-            module_logger = logging.getLogger(module.__module__)
+            module_logger = get_module_logger(module)
 
             m = module(
                 target_path=self.target_path,

src/mvt/common/help.py

@@ -8,7 +8,7 @@ HELP_MSG_VERSION = "Show the currently installed version of MVT"
 HELP_MSG_OUTPUT = "Specify a path to a folder where you want to store JSON results"
 HELP_MSG_IOC = "Path to indicators file (can be invoked multiple time)"
 HELP_MSG_FAST = "Avoid running time/resource consuming features"
-HELP_MSG_LIST_MODULES = "Print list of available modules and exit"
+HELP_MSG_LIST_MODULES = "Print list of available modules and their source, then exit"
 HELP_MSG_MODULE = "Name of a single module you would like to run instead of all"
 HELP_MSG_LOAD_MODULE = (
     "Load custom MVT module(s) from a Python file or folder "

src/mvt/common/module_loader.py

@@ -4,18 +4,28 @@
 #   https://license.mvt.re/1.1/
 
 import hashlib
+import importlib.metadata
 import importlib.util
 import inspect
+import json
 import logging
 import os
 import sys
+from dataclasses import dataclass
+from functools import lru_cache
 from pathlib import Path
 from types import ModuleType
 from typing import Iterable, Optional
 
 from .module import MVTModule
+from .version import MVT_VERSION
 
 MVT_CUSTOM_MODULES_ENV = "MVT_CUSTOM_MODULES"
+MODULES_ENTRY_POINT_GROUP = "mvt.modules"
+EXTERNAL_LOGGER_NAMESPACE = "mvt.ext"
+PLUGIN_PACKAGE_PREFIX = "mvt_plugin_"
+_ORIGIN_ATTRIBUTE = "_mvt_module_origin"
+_PATH_MODULE_PREFIX = "_mvt_custom_module_"
 log = logging.getLogger(__name__)
 
 
@@ -23,15 +33,74 @@ class CustomModuleLoadError(Exception):
     pass
 
 
+@dataclass(frozen=True)
+class ModuleOrigin:
+    """Describes where a loaded module came from, for auditability.
+
+    ``kind`` is one of ``builtin`` (shipped with MVT), ``package`` (loaded
+    from an installed package) or ``path`` (loaded from a file passed with
+    ``--load-module`` or the environment variable).
+    """
+
+    kind: str
+    name: str
+    version: Optional[str] = None
+    commit: Optional[str] = None
+    file_sha256: Optional[str] = None
+
+    @property
+    def label(self) -> str:
+        label = self.name
+        if self.version:
+            label += f"@{self.version}"
+        label = f"'{label}'"
+        if self.commit:
+            label += f" (commit {self.commit})"
+        if self.file_sha256:
+            label += f" (sha256: {self.file_sha256})"
+        return label
+
+
 def _module_name_for_path(path: Path) -> str:
     digest = hashlib.sha256(str(path).encode("utf-8")).hexdigest()[:16]
-    return f"_mvt_custom_module_{path.stem}_{digest}"
+    return f"{_PATH_MODULE_PREFIX}{path.stem}_{digest}"
+
+
+def get_module_logger(module_class: type[MVTModule]) -> logging.Logger:
+    """Return the logger a module's records should be emitted through.
+
+    Modules loaded from installed packages or file paths live outside the
+    "mvt" logger hierarchy, so their records would never reach the handlers
+    attached to the "mvt" logger and instead fall through to
+    logging.lastResort (which prints bare messages and drops anything below
+    WARNING). Their loggers are parented under the "mvt.ext" namespace,
+    keeping external module names from colliding with MVT's own logger
+    tree. File-path modules are named after their file instead of the
+    mangled internal import name, and packages following the recommended
+    "mvt_plugin_<name>" naming convention log under "mvt.ext.<name>".
+    """
+    name = module_class.__module__
+    if name == "mvt" or name.startswith("mvt."):
+        return logging.getLogger(name)
+
+    if name.startswith(_PATH_MODULE_PREFIX):
+        name = Path(get_module_origin(module_class).name).stem
+    else:
+        top_level, separator, rest = name.partition(".")
+        if top_level.startswith(PLUGIN_PACKAGE_PREFIX) and len(top_level) > len(
+            PLUGIN_PACKAGE_PREFIX
+        ):
+            name = top_level[len(PLUGIN_PACKAGE_PREFIX) :] + separator + rest
+
+    return logging.getLogger(f"{EXTERNAL_LOGGER_NAMESPACE}.{name}")
 
 
 def _iter_module_files(path: Path) -> Iterable[Path]:
     if path.is_file():
         if path.suffix != ".py":
-            raise CustomModuleLoadError(f"Custom module file is not a Python file: {path}")
+            raise CustomModuleLoadError(
+                f"Custom module file is not a Python file: {path}"
+            )
         yield path
         return
 
@@ -59,7 +128,9 @@ def _load_python_file(path: Path) -> ModuleType:
     try:
         spec.loader.exec_module(module)
     except Exception as exc:
-        raise CustomModuleLoadError(f"Unable to import custom module {path}: {exc}") from exc
+        raise CustomModuleLoadError(
+            f"Unable to import custom module {path}: {exc}"
+        ) from exc
 
     return module
 
@@ -84,17 +155,156 @@ def load_custom_modules_from_path(path: str) -> list[type[MVTModule]]:
     resolved_path = Path(path).expanduser().resolve()
 
     for module_file in _iter_module_files(resolved_path):
+        file_sha256 = hashlib.sha256(module_file.read_bytes()).hexdigest()
         loaded_module = _load_python_file(module_file)
+        origin = ModuleOrigin(
+            kind="path", name=str(module_file), file_sha256=file_sha256
+        )
         for module_class in discover_mvt_modules(loaded_module):
             key = (str(module_file), module_class.__qualname__)
             if key in seen:
                 continue
             seen.add(key)
+            setattr(module_class, _ORIGIN_ATTRIBUTE, origin)
             custom_modules.append(module_class)
 
     return custom_modules
 
 
+def _module_key(module_class: type[MVTModule]) -> tuple[str, str]:
+    try:
+        source = str(Path(inspect.getfile(module_class)).resolve())
+    except (OSError, TypeError):
+        source = module_class.__module__
+    return (source, module_class.__qualname__)
+
+
+def _distribution_commit(dist: importlib.metadata.Distribution) -> Optional[str]:
+    """Return the VCS commit a distribution was installed from, if recorded.
+
+    Packages installed directly from a repository (``pip install git+...``)
+    record the commit in ``direct_url.json`` (PEP 610).
+    """
+    try:
+        direct_url_text = dist.read_text("direct_url.json")
+        if not direct_url_text:
+            return None
+        commit = json.loads(direct_url_text).get("vcs_info", {}).get("commit_id")
+        return commit if isinstance(commit, str) else None
+    except Exception:
+        return None
+
+
+def _entry_point_origin(entry_point: importlib.metadata.EntryPoint) -> ModuleOrigin:
+    name = entry_point.name
+    version = None
+    commit = None
+    # Manually constructed entry points have no associated distribution.
+    dist = getattr(entry_point, "dist", None)
+    if dist is not None:
+        try:
+            name = dist.name or name
+            version = dist.version
+        except Exception:
+            pass
+        commit = _distribution_commit(dist)
+    return ModuleOrigin(kind="package", name=name, version=version, commit=commit)
+
+
+@lru_cache(maxsize=1)
+def _packages_distributions() -> dict[str, list[str]]:
+    try:
+        return dict(importlib.metadata.packages_distributions())
+    except Exception:
+        return {}
+
+
+def get_module_origin(module_class: type[MVTModule]) -> ModuleOrigin:
+    """Return the origin of a module class for auditing purposes."""
+    origin = module_class.__dict__.get(_ORIGIN_ATTRIBUTE)
+    if isinstance(origin, ModuleOrigin):
+        return origin
+
+    top_level = module_class.__module__.partition(".")[0]
+    if top_level == "mvt":
+        return ModuleOrigin(kind="builtin", name="mvt", version=MVT_VERSION)
+
+    distributions = _packages_distributions().get(top_level)
+    if distributions:
+        name = distributions[0]
+        version = None
+        commit = None
+        try:
+            dist = importlib.metadata.distribution(name)
+            version = dist.version
+            commit = _distribution_commit(dist)
+        except Exception:
+            pass
+        return ModuleOrigin(kind="package", name=name, version=version, commit=commit)
+
+    try:
+        source = str(Path(inspect.getfile(module_class)).resolve())
+    except (OSError, TypeError):
+        source = module_class.__module__
+    return ModuleOrigin(kind="path", name=source)
+
+
+def load_installed_modules() -> list[type[MVTModule]]:
+    """Load MVT modules registered by installed packages.
+
+    Packages register modules in the ``mvt.modules`` entry-point group. Each
+    entry point must resolve to an iterable of MVTModule subclasses, or to a
+    callable which returns one. A broken entry point is skipped with a
+    warning so that a faulty plugin package cannot break MVT.
+    """
+    try:
+        entry_points = importlib.metadata.entry_points(group=MODULES_ENTRY_POINT_GROUP)
+    except Exception as exc:
+        log.warning(
+            "Unable to discover installed module packages in entry-point group %s: %s",
+            MODULES_ENTRY_POINT_GROUP,
+            exc,
+        )
+        return []
+
+    installed_modules: list[type[MVTModule]] = []
+    ordered_entry_points = sorted(
+        entry_points, key=lambda entry_point: (entry_point.name, entry_point.value)
+    )
+    for entry_point in ordered_entry_points:
+        try:
+            loaded = entry_point.load()
+            if callable(loaded) and not isinstance(loaded, type):
+                loaded = loaded()
+            module_classes = list(loaded)
+        except (Exception, SystemExit) as exc:
+            log.warning(
+                "Unable to load modules from entry point %s (%s): %s",
+                entry_point.name,
+                entry_point.value,
+                exc,
+            )
+            continue
+
+        origin = _entry_point_origin(entry_point)
+        for module_class in module_classes:
+            if not (
+                isinstance(module_class, type) and issubclass(module_class, MVTModule)
+            ):
+                log.warning(
+                    "Entry point %s (%s) provided %r which is not an "
+                    "MVTModule subclass",
+                    entry_point.name,
+                    entry_point.value,
+                    module_class,
+                )
+                continue
+            setattr(module_class, _ORIGIN_ATTRIBUTE, origin)
+            installed_modules.append(module_class)
+
+    return installed_modules
+
+
 def load_custom_modules(paths: Optional[Iterable[str]] = None) -> list[type[MVTModule]]:
     search_paths: list[str] = []
     env_path = os.environ.get(MVT_CUSTOM_MODULES_ENV)
@@ -105,10 +315,17 @@ def load_custom_modules(paths: Optional[Iterable[str]] = None) -> list[type[MVTM
 
     custom_modules: list[type[MVTModule]] = []
     seen: set[tuple[str, str]] = set()
+
+    for module_class in load_installed_modules():
+        key = _module_key(module_class)
+        if key in seen:
+            continue
+        seen.add(key)
+        custom_modules.append(module_class)
+
     for path in search_paths:
         for module_class in load_custom_modules_from_path(path):
-            source = Path(inspect.getfile(module_class)).resolve()
+            key = _module_key(module_class)
-            key = (str(source), module_class.__qualname__)
             if key in seen:
                 continue
             seen.add(key)

src/mvt/common/utils.py

@@ -239,6 +239,13 @@ def init_logging(verbose: bool = False):
     """
     log = logging.getLogger("mvt")
     log.setLevel(logging.DEBUG)
+
+    # Importing an MVT CLI module calls init_logging() at import time, and
+    # loaded module packages may import one indirectly. Keep this idempotent
+    # so console log lines are not duplicated by a second handler.
+    if any(isinstance(handler, MVTLogHandler) for handler in log.handlers):
+        return
+
     consoleHandler = MVTLogHandler()
     consoleHandler.setFormatter(logging.Formatter("%(message)s"))
     if verbose:

tests/common/test_module_loader.py

@@ -3,10 +3,12 @@ import pytest
 from mvt.common.module import MVTModule
 from mvt.common.module_loader import (
     CustomModuleLoadError,
+    get_module_logger,
     load_custom_modules,
     load_custom_modules_from_path,
     module_supports_command,
 )
+from mvt.ios.modules.mixed.whatsapp import Whatsapp
 
 
 MODULE_TEMPLATE = """
@@ -144,3 +146,44 @@ def test_module_supports_command_honors_supported_commands(tmp_path):
 
     assert module_supports_command(module, "ios", "check-backup")
     assert not module_supports_command(module, "ios", "check-fs")
+
+
+def test_get_module_logger_keeps_builtin_names():
+    assert get_module_logger(Whatsapp).name == "mvt.ios.modules.mixed.whatsapp"
+
+
+def test_get_module_logger_parents_package_modules_under_mvt_ext():
+    class PackageModule(MVTModule):
+        pass
+
+    PackageModule.__module__ = "some_plugin_package.ios.custom"
+
+    assert (
+        get_module_logger(PackageModule).name
+        == "mvt.ext.some_plugin_package.ios.custom"
+    )
+
+
+def test_get_module_logger_strips_the_plugin_package_prefix():
+    class PluginModule(MVTModule):
+        pass
+
+    PluginModule.__module__ = "mvt_plugin_amnesty_custom.ios.custom"
+
+    assert get_module_logger(PluginModule).name == "mvt.ext.amnesty_custom.ios.custom"
+
+
+def test_get_module_logger_only_strips_the_prefix_from_the_top_level():
+    class NestedModule(MVTModule):
+        pass
+
+    NestedModule.__module__ = "other_package.mvt_plugin_sub"
+
+    assert get_module_logger(NestedModule).name == "mvt.ext.other_package.mvt_plugin_sub"
+
+
+def test_get_module_logger_names_path_modules_after_their_file(tmp_path):
+    module_path = _write_module(tmp_path / "my_custom_module.py", "PathModule")
+    module = load_custom_modules_from_path(str(module_path))[0]
+
+    assert get_module_logger(module).name == "mvt.ext.my_custom_module"

tests/common/test_utils.py

@@ -8,6 +8,7 @@ import logging
 import os
 from datetime import datetime
 
+from mvt.common.log import MVTLogHandler
 from mvt.common.utils import (
     CustomJSONEncoder,
     convert_datetime_to_iso,
@@ -16,6 +17,7 @@ from mvt.common.utils import (
     convert_unix_to_utc_datetime,
     generate_hashes_from_path,
     get_sha256_from_file_path,
+    init_logging,
 )
 
 from ..utils import get_artifact_folder
@@ -103,3 +105,20 @@ class TestCustomJSONEncoder:
             json.dumps({"name": "家".encode()}, cls=CustomJSONEncoder)
             == '{"name": "\\u5bb6"}'
         )
+
+
+class TestInitLogging:
+    def test__init_logging_is_idempotent(self):
+        # Loaded module packages may import an MVT CLI module, which calls
+        # init_logging() again at import time. A second call must not add
+        # a duplicate console handler.
+        log = logging.getLogger("mvt")
+        init_logging()
+        handler_count = sum(
+            isinstance(handler, MVTLogHandler) for handler in log.handlers
+        )
+        init_logging()
+        assert (
+            sum(isinstance(handler, MVTLogHandler) for handler in log.handlers)
+            == handler_count
+        )

tests/test_custom_modules.py

@@ -1,3 +1,7 @@
+import hashlib
+import importlib.metadata
+import json
+
 from click.testing import CliRunner
 
 from mvt.android.cli import check_bugreport
@@ -5,7 +9,9 @@ from mvt.android.cmd_check_androidqf import CmdAndroidCheckAndroidQF
 from mvt.android.cmd_check_backup import CmdAndroidCheckBackup
 from mvt.android.cmd_check_bugreport import CmdAndroidCheckBugreport
 from mvt.android.cmd_check_intrusion_logs import CmdAndroidCheckIntrusionLogs
+from mvt.common import module_loader
 from mvt.common.module import MVTModule
+from mvt.common.version import MVT_VERSION
 from mvt.ios.cli import check_backup, check_fs
 
 
@@ -106,6 +112,150 @@ def test_custom_modules_load_from_environment_without_cli_flag(tmp_path, monkeyp
     assert "EnvBugreportModule" in result.output
 
 
+class InstalledPackageModule(MVTModule):
+    supported_commands = (("ios", "check-backup"),)
+
+
+def get_installed_package_modules():
+    return [InstalledPackageModule]
+
+
+def _fake_entry_points(monkeypatch, value, name="test-modules"):
+    entry_point = importlib.metadata.EntryPoint(
+        name=name, value=value, group=module_loader.MODULES_ENTRY_POINT_GROUP
+    )
+
+    def fake_entry_points(*, group):
+        assert group == module_loader.MODULES_ENTRY_POINT_GROUP
+        return [entry_point]
+
+    monkeypatch.setattr(
+        module_loader.importlib.metadata, "entry_points", fake_entry_points
+    )
+
+
+def test_installed_module_package_loads_from_entry_point(monkeypatch):
+    _fake_entry_points(monkeypatch, f"{__name__}:get_installed_package_modules")
+
+    modules = module_loader.load_custom_modules()
+
+    assert modules == [InstalledPackageModule]
+
+
+def test_broken_module_entry_point_is_skipped(monkeypatch, caplog):
+    _fake_entry_points(monkeypatch, "nonexistent_module_xyz:get_modules")
+
+    with caplog.at_level("WARNING"):
+        modules = module_loader.load_custom_modules()
+
+    assert modules == []
+    assert "Unable to load modules from entry point" in caplog.text
+
+
+def test_entry_point_module_deduplicated_against_paths(monkeypatch, tmp_path):
+    _fake_entry_points(monkeypatch, f"{__name__}:get_installed_package_modules")
+    module_path = _write_custom_module(
+        tmp_path / "custom.py",
+        "PathLoadedModule",
+        (("ios", "check-backup"),),
+    )
+
+    modules = module_loader.load_custom_modules([str(module_path)])
+
+    assert [module.__name__ for module in modules] == [
+        "InstalledPackageModule",
+        "PathLoadedModule",
+    ]
+
+
+def test_list_modules_shows_module_sources(tmp_path, caplog):
+    module_path = _write_custom_module(
+        tmp_path / "custom.py",
+        "SourcedBackupModule",
+        (("ios", "check-backup"),),
+    )
+    file_sha256 = hashlib.sha256(module_path.read_bytes()).hexdigest()
+    custom_modules = module_loader.load_custom_modules([str(module_path)])
+
+    from mvt.ios.cmd_check_backup import CmdIOSCheckBackup
+
+    cmd = CmdIOSCheckBackup(target_path=str(tmp_path), custom_modules=custom_modules)
+    cmd.list_modules()
+
+    assert f" - Modules from 'mvt@{MVT_VERSION}':" in caplog.text
+    assert (
+        f" - Modules from '{module_path}' (sha256: {file_sha256}): SourcedBackupModule"
+        in caplog.text
+    )
+
+
+def test_builtin_module_origin():
+    from mvt.ios.modules.backup import BACKUP_MODULES
+
+    origin = module_loader.get_module_origin(BACKUP_MODULES[0])
+
+    assert origin.kind == "builtin"
+    assert origin.name == "mvt"
+    assert origin.version == MVT_VERSION
+
+
+def test_installed_module_origin(monkeypatch):
+    _fake_entry_points(monkeypatch, f"{__name__}:get_installed_package_modules")
+
+    modules = module_loader.load_custom_modules()
+
+    origin = module_loader.get_module_origin(modules[0])
+    assert origin.kind == "package"
+    assert origin.name == "test-modules"
+
+
+def test_distribution_commit_read_from_direct_url():
+    class FakeDistribution:
+        def read_text(self, filename):
+            assert filename == "direct_url.json"
+            return json.dumps(
+                {
+                    "url": "https://github.com/example/example-modules",
+                    "vcs_info": {"commit_id": "abc1234", "vcs": "git"},
+                }
+            )
+
+    assert module_loader._distribution_commit(FakeDistribution()) == "abc1234"
+
+
+def test_command_log_records_loaded_modules(tmp_path):
+    (tmp_path / "Manifest.db").touch()
+    (tmp_path / "Info.plist").touch()
+    module_path = _write_custom_module(
+        tmp_path / "custom.py",
+        "AuditedRunModule",
+        (("ios", "check-backup"),),
+        slug="audited_run_module",
+    )
+    file_sha256 = hashlib.sha256(module_path.read_bytes()).hexdigest()
+    output_path = tmp_path / "out"
+
+    result = CliRunner().invoke(
+        check_backup,
+        [
+            "--module",
+            "AuditedRunModule",
+            "--load-module",
+            str(module_path),
+            "--output",
+            str(output_path),
+            str(tmp_path),
+        ],
+    )
+
+    assert result.exit_code == 0
+    command_log = (output_path / "command.log").read_text(encoding="utf-8")
+    assert (
+        f"Loaded 1 check-backup modules from '{module_path}' "
+        f"(sha256: {file_sha256}): AuditedRunModule" in command_log
+    )
+
+
 class NestedBugreportModule(MVTModule):
     supported_commands = (("android", "check-bugreport"),)