Hardening: use unsafe for ansible vars, ensure API use of JinjaTurtle uses safe XML parsing, avoid symlinks

tests/test_injection_security.py

@@ -29,6 +29,21 @@ from jinjaturtle.escape import (
 TRIP = "__TRIPWIRE_FIRED__"
 
 
+class _UnsafeAwareLoader(pyyaml.SafeLoader):
+    pass
+
+
+def _construct_unsafe(loader: _UnsafeAwareLoader, node: pyyaml.Node):
+    return loader.construct_scalar(node)
+
+
+_UnsafeAwareLoader.add_constructor("!unsafe", _construct_unsafe)
+
+
+def _safe_load_defaults(text: str):
+    return pyyaml.load(text, Loader=_UnsafeAwareLoader)
+
+
 class _Boom:
     """Returns the tripwire sentinel for any access/call an SSTI payload makes."""
 
@@ -82,7 +97,7 @@ def _run_jinjaturtle(tmp_path: Path, source_name: str, body: str, fmt: str):
         text=True,
     )
     assert res.returncode == 0, f"generation failed: {res.stderr}"
-    defaults = pyyaml.safe_load(dfl.read_text()) or {}
+    defaults = _safe_load_defaults(dfl.read_text()) or {}
     return tpl.read_text(), defaults
 
 

tests/test_security_hardening.py

@@ -0,0 +1,120 @@
+from __future__ import annotations
+
+from pathlib import Path
+import os
+
+import pytest
+import yaml
+from defusedxml.common import EntitiesForbidden
+
+from jinjaturtle import cli
+from jinjaturtle.core import generate_ansible_yaml, parse_config, flatten_config
+from jinjaturtle.multi import is_supported_file, iter_supported_files, process_directory
+from jinjaturtle.output_safety import OutputPathError, write_text_safely
+
+
+class UnsafeAwareLoader(yaml.SafeLoader):
+    pass
+
+
+def _unsafe(loader: UnsafeAwareLoader, node: yaml.Node):
+    return loader.construct_scalar(node)
+
+
+UnsafeAwareLoader.add_constructor("!unsafe", _unsafe)
+
+
+def test_jinja_values_are_emitted_as_ansible_unsafe(tmp_path: Path):
+    src = tmp_path / "app.ini"
+    src.write_text("[main]\ncmd = {{ lookup('pipe','id') }}\n", encoding="utf-8")
+
+    fmt, parsed = parse_config(src)
+    defaults_yaml = generate_ansible_yaml("role", flatten_config(fmt, parsed))
+
+    assert "role_main_cmd: !unsafe" in defaults_yaml
+    assert "{{ lookup(''pipe'',''id'') }}" in defaults_yaml
+    loaded = yaml.load(defaults_yaml, Loader=UnsafeAwareLoader)
+    assert loaded["role_main_cmd"] == "{{ lookup('pipe','id') }}"
+
+
+def test_folder_mode_marks_nested_jinja_values_and_ids_unsafe(tmp_path: Path):
+    src = tmp_path / "src"
+    src.mkdir()
+    # Filename ids are source-derived values too.
+    (src / "{{ bad }}.yaml").write_text(
+        "message: \"{{ lookup('pipe','id') }}\"\n", encoding="utf-8"
+    )
+
+    defaults_yaml, _outputs = process_directory(
+        src, recursive=False, role_prefix="role"
+    )
+
+    assert "id: !unsafe" in defaults_yaml
+    assert "role_message: !unsafe" in defaults_yaml
+    loaded = yaml.load(defaults_yaml, Loader=UnsafeAwareLoader)
+    assert loaded["role_items"][0]["id"] == "{{ bad }}.yaml"
+    assert loaded["role_items"][0]["role_message"] == "{{ lookup('pipe','id') }}"
+
+
+def test_xml_parser_rejects_entities_when_called_as_library(tmp_path: Path):
+    src = tmp_path / "bad.xml"
+    src.write_text(
+        "<!DOCTYPE root [<!ENTITY xxe SYSTEM 'file:///etc/passwd'>]><root>&xxe;</root>",
+        encoding="utf-8",
+    )
+
+    with pytest.raises(EntitiesForbidden):
+        parse_config(src, "xml")
+
+
+def test_folder_mode_does_not_follow_symlinked_files(tmp_path: Path):
+    real = tmp_path / "secret.ini"
+    real.write_text("[main]\nsecret=yes\n", encoding="utf-8")
+    root = tmp_path / "root"
+    root.mkdir()
+    link = root / "link.ini"
+    link.symlink_to(real)
+
+    assert not is_supported_file(link)
+    assert iter_supported_files(root, recursive=False) == []
+    assert iter_supported_files(root, recursive=True) == []
+
+
+@pytest.mark.skipif(not hasattr(os, "symlink"), reason="symlinks unavailable")
+def test_cli_refuses_to_write_through_final_symlink(tmp_path: Path):
+    target = tmp_path / "target.txt"
+    target.write_text("keep\n", encoding="utf-8")
+    link = tmp_path / "out.yml"
+    link.symlink_to(target)
+
+    with pytest.raises(OutputPathError):
+        write_text_safely(link, "replace\n")
+
+    assert target.read_text(encoding="utf-8") == "keep\n"
+    assert link.is_symlink()
+
+
+def test_cli_refuses_symlinked_output_parent(tmp_path: Path):
+    real_dir = tmp_path / "real"
+    real_dir.mkdir()
+    link_dir = tmp_path / "linkdir"
+    link_dir.symlink_to(real_dir, target_is_directory=True)
+
+    with pytest.raises(OutputPathError):
+        write_text_safely(link_dir / "out.yml", "data\n")
+
+    assert not (real_dir / "out.yml").exists()
+
+
+def test_cli_reports_unsafe_output_path_without_overwriting_symlink(tmp_path: Path):
+    cfg = tmp_path / "app.ini"
+    cfg.write_text("[main]\nname = ok\n", encoding="utf-8")
+    target = tmp_path / "target.yml"
+    target.write_text("keep\n", encoding="utf-8")
+    link = tmp_path / "defaults.yml"
+    link.symlink_to(target)
+
+    exit_code = cli._main([str(cfg), "--defaults-output", str(link)])
+
+    assert exit_code == 2
+    assert target.read_text(encoding="utf-8") == "keep\n"