`54e7e6a`

Refuse executable files in packs

Authored by

espadonne 3 weeks ago

Status	File	+	-
M	`src/dlm/cli/commands.py`	4	1
M	`src/dlm/pack/__init__.py`	2	0
M	`src/dlm/pack/errors.py`	16	0
M	`src/dlm/pack/packer.py`	11	1
M	`tests/unit/pack/test_packer.py`	18	1

src/dlm/cli/commands.pymodified

      from rich.console import Console
      from dlm.doc.errors import DlmParseError
 -    from dlm.pack.errors import BaseLicenseRefusedError
 +    from dlm.pack.errors import BaseLicenseRefusedError, PackError
      from dlm.pack.packer import pack
      console = Console(stderr=True)
      except BaseLicenseRefusedError as exc:
          console.print(f"[red]pack:[/red] {exc}")
          raise typer.Exit(code=1) from exc
 +    except PackError as exc:
 +        console.print(f"[red]pack:[/red] {exc}")
 +        raise typer.Exit(code=1) from exc
      except DlmParseError as exc:
          console.print(f"[red]parse:[/red] {exc}")
          raise typer.Exit(code=1) from exc

src/dlm/pack/__init__.pymodified

  from dlm.pack.errors import (
      BaseLicenseRefusedError,
      PackError,
 +    PackExecutableFileError,
      PackFormatVersionError,
      PackIntegrityError,
      PackLayoutError,
      "HEADER_FILENAME",
      "MANIFEST_FILENAME",
      "PackError",
 +    "PackExecutableFileError",
      "PackFormatVersionError",
      "PackHeader",
      "PackIntegrityError",

src/dlm/pack/errors.pymodified

+         )
          self.base_key = base_key
          self.license_url = license_url
++
++
 +class PackExecutableFileError(PackError):
 +    """Pack refused because a would-be-packed store file has execute bits set.
++
 +    The pack format normalizes file modes to deterministic 0o644 / 0o755
 +    headers. Refusing executable files keeps that normalization honest:
 +    we never silently strip an x-bit from user data.
 +    """
++
 +    def __init__(self, relpath: str) -> None:
 +        super().__init__(
 +            f"store file {relpath!r} is executable; pack refuses to silently strip "
 +            "the x-bit. Clear the executable bit or move the file out of the store."
 +        )
 +        self.relpath = relpath

src/dlm/pack/packer.pymodified

  from pathlib import Path
  from typing import TYPE_CHECKING, Any
 -from dlm.pack.errors import BaseLicenseRefusedError
 +from dlm.pack.errors import BaseLicenseRefusedError, PackExecutableFileError
  from dlm.pack.format import (
      CURRENT_PACK_FORMAT_VERSION,
      ContentType,
          if relpath == store.lock.name:
              # The lockfile itself is state-of-this-process only.
              continue
 +        _assert_no_executable_files(child, store_root=store.root)
          dest = store_dst / relpath
          if child.is_dir():
              shutil.copytree(child, dest, symlinks=False)
              shutil.copy2(child, dest)
 +def _assert_no_executable_files(path: Path, *, store_root: Path) -> None:
 +    """Refuse pack inputs that would lose executable bits in tar normalization."""
++
 +    candidates = [path] if path.is_file() else sorted(p for p in path.rglob("*") if p.is_file())
 +    for candidate in candidates:
 +        if candidate.stat().st_mode & 0o111:
 +            raise PackExecutableFileError(candidate.relative_to(store_root).as_posix())
++
++
  def _normalize_tarinfo(info: tarfile.TarInfo) -> tarfile.TarInfo:
      """Strip host-specific metadata so two packs of identical content match byte-for-byte.

tests/unit/pack/test_packer.pymodified

  from typer.testing import CliRunner
  from dlm.cli.app import app
 -from dlm.pack.errors import BaseLicenseRefusedError
 +from dlm.pack.errors import BaseLicenseRefusedError, PackExecutableFileError
  from dlm.pack.packer import _platform_hint, pack
          assert observed.get("holder_pid") == _os.getpid()
 +class TestExecutableBitRefusal:
 +    def test_refuses_executable_file_in_store_tree(self, tmp_path: Path) -> None:
 +        doc = _scaffold_doc_and_store(tmp_path)
++
 +        from dlm.doc.parser import parse_file
 +        from dlm.store.paths import for_dlm
++
 +        parsed = parse_file(doc)
 +        store = for_dlm(parsed.frontmatter.dlm_id)
 +        hook = store.root / "resume.sh"
 +        hook.write_text("#!/bin/sh\necho nope\n", encoding="utf-8")
 +        hook.chmod(0o755)
++
 +        with pytest.raises(PackExecutableFileError, match="resume\\.sh"):
 +            pack(doc)
++
++
  class TestPlatformHint:
      def test_import_error_falls_back_to_sys_platform(
          self, caplog: pytest.LogCaptureFixture