"""Red-team tests for the host-side path-confinement boundary (`_safe_path`). `_safe_path()` guards the three endpoints that turn a caller-supplied path into a host filesystem read / open: GET /api/file/preview?path=... (read file contents) GET /api/file/tree?root=... (list a directory) POST /api/workspace/open (open in Finder/terminal) The allowed roots are the workspace root and the Hermes home dir. The interesting attacks are the ones that *look* like an allowed path but resolve elsewhere: * a symlink placed inside the workspace whose target is outside every root, * `..` traversal that climbs out of the workspace, * an absolute path straight at a host secret. The fix relies on `Path(raw).resolve()` following symlinks *before* the containment check. These tests pin that behaviour so a future "optimisation" that drops the resolve (or checks the literal path) can't silently re-open the hole. Existing happy-path / basic-rejection coverage lives in test_server.py and test_workspace_open.py; this file is the adversarial layer. """ import os import pytest import pytest_asyncio from httpx import ASGITransport, AsyncClient from agent_gui.server import create_app @pytest.fixture() def roots(tmp_path): """(hermes_home, workspace_root) with the workspace under its own dir. Unlike test_server.py (where home == tmp_path, so the workspace sits *inside* home), here home and the workspace are siblings and `secrets/` is a third sibling outside BOTH roots — a realistic escape target. """ home = tmp_path / "hermes_home" ws = tmp_path / "workspace" secrets = tmp_path / "secrets" for d in (home, ws, secrets): d.mkdir() (secrets / "id_rsa").write_text("PRIVATE KEY\n") return home, ws, secrets @pytest.fixture() def app(roots): home, ws, _ = roots return create_app(hermes_home=str(home), workspace_root=str(ws)) @pytest_asyncio.fixture() async def client(app): async with AsyncClient(transport=ASGITransport(app=app), base_url="http://test") as c: yield c # ── Symlink escape ─────────────────────────────────────────────────────────── @pytest.mark.asyncio async def test_preview_symlink_out_of_workspace_is_forbidden(client, roots): """A symlink that lives inside the workspace but points at a host secret must not leak the secret — `.resolve()` follows the link, containment then fails.""" home, ws, secrets = roots link = ws / "innocent.txt" link.symlink_to(secrets / "id_rsa") r = await client.get("/api/file/preview", params={"path": str(link)}) assert r.status_code == 403 assert "PRIVATE KEY" not in r.text @pytest.mark.asyncio async def test_tree_symlinked_dir_out_of_workspace_is_forbidden(client, roots): """A symlinked directory inside the workspace pointing outside is rejected.""" home, ws, secrets = roots link = ws / "shared" link.symlink_to(secrets, target_is_directory=True) r = await client.get("/api/file/tree", params={"root": str(link)}) assert r.status_code == 403 assert "id_rsa" not in r.text @pytest.mark.asyncio async def test_open_symlink_out_of_workspace_is_forbidden(client, roots): """workspace/open must refuse a symlink that escapes the allowed roots.""" home, ws, secrets = roots link = ws / "shortcut" link.symlink_to(secrets, target_is_directory=True) r = await client.post("/api/workspace/open", json={"path": str(link)}) assert r.status_code == 403 # ── `..` traversal ─────────────────────────────────────────────────────────── @pytest.mark.asyncio async def test_preview_dotdot_traversal_is_forbidden(client, roots): """`/../secrets/id_rsa` resolves outside the roots → 403.""" home, ws, secrets = roots sneaky = ws / ".." / "secrets" / "id_rsa" r = await client.get("/api/file/preview", params={"path": str(sneaky)}) assert r.status_code == 403 assert "PRIVATE KEY" not in r.text @pytest.mark.asyncio async def test_preview_absolute_secret_path_is_forbidden(client, roots): """A plain absolute path at a host secret is rejected outright.""" home, ws, secrets = roots r = await client.get("/api/file/preview", params={"path": str(secrets / "id_rsa")}) assert r.status_code == 403 # ── The boundary must not over-block legitimate access ─────────────────────── @pytest.mark.asyncio async def test_symlink_within_workspace_is_allowed(client, roots): """A symlink whose target is *also* inside the workspace stays allowed — the guard blocks escapes, not indirection per se.""" home, ws, secrets = roots real = ws / "real.txt" real.write_text("hello from inside\n") link = ws / "alias.txt" link.symlink_to(real) r = await client.get("/api/file/preview", params={"path": str(link)}) assert r.status_code == 200 assert "hello from inside" in r.json()["content"] @pytest.mark.asyncio async def test_file_under_hermes_home_is_allowed(client, roots): """Hermes home is the second allowed root (config/memory previews rely on it).""" home, ws, secrets = roots cfg = home / "notes.log" cfg.write_text("log line\n") r = await client.get("/api/file/preview", params={"path": str(cfg)}) assert r.status_code == 200 assert "log line" in r.json()["content"]