Validate declarative flow definition paths (#6311)

lib/cli/src/crewai_cli/run_declarative_flow.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 import json
-from pathlib import Path
+from pathlib import Path, PureWindowsPath
 import subprocess
 from typing import Any
 
@@ -12,7 +12,7 @@ from crewai_cli.utils import build_env_with_all_tool_credentials
 
 
 def run_declarative_flow_in_project_env(
-    definition: str, inputs: str | None = None
+    definition: str | Path, inputs: str | None = None
 ) -> None:
     """Run a declarative flow inside the project's Python environment."""
     if is_declarative_flow_project_env() or not _has_project_file():
@@ -25,7 +25,7 @@ def run_declarative_flow_in_project_env(
     _execute_declarative_flow_command(["uv", "run", "crewai", "run"])
 
 
-def plot_declarative_flow_in_project_env(definition: str) -> None:
+def plot_declarative_flow_in_project_env(definition: str | Path) -> None:
     """Plot a declarative flow inside the project's Python environment."""
     if is_declarative_flow_project_env() or not _has_project_file():
         plot_declarative_flow(definition=definition)
@@ -34,7 +34,7 @@ def plot_declarative_flow_in_project_env(definition: str) -> None:
     _execute_declarative_flow_command(["uv", "run", "crewai", "flow", "plot"])
 
 
-def run_declarative_flow(definition: str, inputs: str | None = None) -> None:
+def run_declarative_flow(definition: str | Path, inputs: str | None = None) -> None:
     """Run a declarative flow from a definition path."""
     parsed_inputs = _parse_inputs(inputs)
 
@@ -50,7 +50,7 @@ def run_declarative_flow(definition: str, inputs: str | None = None) -> None:
     click.echo(_format_result(result))
 
 
-def plot_declarative_flow(definition: str) -> None:
+def plot_declarative_flow(definition: str | Path) -> None:
     """Plot a declarative flow from a definition path."""
     try:
         flow = load_declarative_flow(definition)
@@ -62,7 +62,7 @@ def plot_declarative_flow(definition: str) -> None:
         raise SystemExit(1) from exc
 
 
-def load_declarative_flow(definition: str) -> Any:
+def load_declarative_flow(definition: str | Path) -> Any:
     """Load a declarative Flow instance from a definition path."""
     try:
         from crewai.flow.flow import Flow
@@ -102,7 +102,8 @@ def load_declarative_flow(definition: str) -> Any:
 
 def configured_project_declarative_flow(
     pyproject_data: dict[str, Any] | None = None,
-) -> str | None:
+    project_root: Path | None = None,
+) -> Path | None:
     """Return the configured declarative flow source for flow projects."""
     if pyproject_data is None:
         try:
@@ -118,7 +119,66 @@ def configured_project_declarative_flow(
     definition = crewai_config.get("definition")
     if not isinstance(definition, str):
         return None
-    return definition.strip() or None
+    definition = definition.strip()
+    if not definition:
+        return None
+
+    return _resolve_project_definition_path(
+        definition=definition,
+        project_root=project_root or Path.cwd(),
+    )
+
+
+def _resolve_project_definition_path(definition: str, project_root: Path) -> Path:
+    definition_path = Path(definition)
+    windows_definition_path = PureWindowsPath(definition)
+
+    if definition.startswith("~"):
+        raise click.UsageError(
+            "[tool.crewai] definition must be a project-local path; "
+            f"got {definition!r}."
+        )
+
+    if definition_path.is_absolute() or windows_definition_path.is_absolute():
+        raise click.UsageError(
+            "[tool.crewai] definition must be relative to the project root; "
+            f"got {definition!r}."
+        )
+
+    try:
+        root = project_root.resolve(strict=True)
+    except OSError as exc:
+        raise click.UsageError(
+            f"Invalid project root for [tool.crewai] definition: {exc}"
+        ) from exc
+
+    candidate = root / definition_path
+    try:
+        resolved_candidate = candidate.resolve(strict=False)
+    except OSError as exc:
+        raise click.UsageError(
+            f"Invalid [tool.crewai] definition path {definition!r}: {exc}"
+        ) from exc
+
+    if not resolved_candidate.is_relative_to(root):
+        raise click.UsageError(
+            "[tool.crewai] definition must resolve inside the project root; "
+            f"got {definition!r}."
+        )
+
+    if not resolved_candidate.exists():
+        raise click.UsageError(
+            "[tool.crewai] definition must point to an existing file; "
+            f"got {definition!r}."
+        )
+
+    if not resolved_candidate.is_file():
+        raise click.UsageError(
+            "[tool.crewai] definition must point to a regular file; "
+            f"got {definition!r}."
+        )
+
+    return resolved_candidate
 
 
 def _execute_declarative_flow_command(command: list[str]) -> None:

lib/cli/tests/test_flow_commands.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 from pathlib import Path
 import subprocess
 
+import click
 import pytest
 from click.testing import CliRunner
 
@@ -107,6 +108,8 @@ def test_configured_project_declarative_flow(
     monkeypatch: pytest.MonkeyPatch, tmp_path: Path
 ) -> None:
     monkeypatch.chdir(tmp_path)
+    definition_path = tmp_path / "flow.yaml"
+    definition_path.write_text(FLOW_YAML, encoding="utf-8")
     (tmp_path / "pyproject.toml").write_text(
         '[tool.crewai]\ntype = "flow"\ndefinition = " flow.yaml "\n',
         encoding="utf-8",
@@ -114,4 +117,132 @@ def test_configured_project_declarative_flow(
 
     from crewai_cli.run_declarative_flow import configured_project_declarative_flow
 
-    assert configured_project_declarative_flow() == "flow.yaml"
+    assert configured_project_declarative_flow() == definition_path.resolve()
+
+
+@pytest.mark.parametrize(
+    ("definition", "expected_error"),
+    [
+        ("C:/tmp/flow.yaml", "must be relative to the project root"),
+        ("~/flow.yaml", "must be a project-local path"),
+        ("../flow.yaml", "must resolve inside the project root"),
+    ],
+)
+def test_configured_project_declarative_flow_rejects_unsafe_paths(
+    monkeypatch: pytest.MonkeyPatch,
+    tmp_path: Path,
+    definition: str,
+    expected_error: str,
+) -> None:
+    monkeypatch.chdir(tmp_path)
+    (tmp_path / "pyproject.toml").write_text(
+        f'[tool.crewai]\ntype = "flow"\ndefinition = "{definition}"\n',
+        encoding="utf-8",
+    )
+
+    from crewai_cli.run_declarative_flow import configured_project_declarative_flow
+
+    with pytest.raises(click.UsageError) as exc_info:
+        configured_project_declarative_flow()
+
+    assert expected_error in exc_info.value.message
+
+
+def test_configured_project_declarative_flow_allows_normalized_project_path(
+    monkeypatch: pytest.MonkeyPatch,
+    tmp_path: Path,
+) -> None:
+    monkeypatch.chdir(tmp_path)
+    definition_path = tmp_path / "flow.yaml"
+    definition_path.write_text(FLOW_YAML, encoding="utf-8")
+    (tmp_path / "src").mkdir()
+    (tmp_path / "pyproject.toml").write_text(
+        '[tool.crewai]\ntype = "flow"\ndefinition = "src/../flow.yaml"\n',
+        encoding="utf-8",
+    )
+
+    from crewai_cli.run_declarative_flow import configured_project_declarative_flow
+
+    assert configured_project_declarative_flow() == definition_path.resolve()
+
+
+def test_configured_project_declarative_flow_rejects_absolute_path(
+    monkeypatch: pytest.MonkeyPatch,
+    tmp_path: Path,
+) -> None:
+    monkeypatch.chdir(tmp_path)
+    definition = tmp_path / "flow.yaml"
+    (tmp_path / "pyproject.toml").write_text(
+        f'[tool.crewai]\ntype = "flow"\ndefinition = "{definition.as_posix()}"\n',
+        encoding="utf-8",
+    )
+
+    from crewai_cli.run_declarative_flow import configured_project_declarative_flow
+
+    with pytest.raises(click.UsageError) as exc_info:
+        configured_project_declarative_flow()
+
+    assert "must be relative to the project root" in exc_info.value.message
+
+
+def test_configured_project_declarative_flow_rejects_symlink_escape(
+    monkeypatch: pytest.MonkeyPatch,
+    tmp_path: Path,
+) -> None:
+    monkeypatch.chdir(tmp_path)
+    outside_definition = tmp_path.parent / "outside-flow.yaml"
+    outside_definition.write_text(FLOW_YAML, encoding="utf-8")
+    link = tmp_path / "flow.yaml"
+    try:
+        link.symlink_to(outside_definition)
+    except (NotImplementedError, OSError) as exc:
+        pytest.skip(f"symlinks unavailable: {exc}")
+
+    (tmp_path / "pyproject.toml").write_text(
+        '[tool.crewai]\ntype = "flow"\ndefinition = "flow.yaml"\n',
+        encoding="utf-8",
+    )
+
+    from crewai_cli.run_declarative_flow import configured_project_declarative_flow
+
+    with pytest.raises(click.UsageError) as exc_info:
+        configured_project_declarative_flow()
+
+    assert "must resolve inside the project root" in exc_info.value.message
+
+
+def test_configured_project_declarative_flow_rejects_missing_file(
+    monkeypatch: pytest.MonkeyPatch,
+    tmp_path: Path,
+) -> None:
+    monkeypatch.chdir(tmp_path)
+    (tmp_path / "pyproject.toml").write_text(
+        '[tool.crewai]\ntype = "flow"\ndefinition = "missing-flow.yaml"\n',
+        encoding="utf-8",
+    )
+
+    from crewai_cli.run_declarative_flow import configured_project_declarative_flow
+
+    with pytest.raises(click.UsageError) as exc_info:
+        configured_project_declarative_flow()
+
+    assert "must point to an existing file" in exc_info.value.message
+
+
+def test_configured_project_declarative_flow_rejects_directory(
+    monkeypatch: pytest.MonkeyPatch,
+    tmp_path: Path,
+) -> None:
+    monkeypatch.chdir(tmp_path)
+    (tmp_path / "flow.yaml").mkdir()
+    (tmp_path / "pyproject.toml").write_text(
+        '[tool.crewai]\ntype = "flow"\ndefinition = "flow.yaml"\n',
+        encoding="utf-8",
+    )
+
+    from crewai_cli.run_declarative_flow import configured_project_declarative_flow
+
+    with pytest.raises(click.UsageError) as exc_info:
+        configured_project_declarative_flow()
+
+    assert "must point to a regular file" in exc_info.value.message

lib/cli/tests/test_run_crew.py

@@ -705,9 +705,14 @@ def test_run_crew_rejects_filename_for_flow_project(monkeypatch):
     assert "--filename can only be used when running crews" in exc_info.value.message
 
 
-def test_run_crew_runs_configured_declarative_flow_project(monkeypatch, capsys):
+def test_run_crew_runs_configured_declarative_flow_project(
+    monkeypatch, tmp_path: Path, capsys
+):
     calls = []
 
+    monkeypatch.chdir(tmp_path)
+    definition_path = tmp_path / "flow.yaml"
+    definition_path.write_text("schema: crewai.flow/v1\n", encoding="utf-8")
     monkeypatch.setattr(run_crew_module, "_has_json_crew", lambda: False)
     monkeypatch.setattr(
         run_crew_module,
@@ -734,4 +739,4 @@ def test_run_crew_runs_configured_declarative_flow_project(monkeypatch, capsys):
     run_crew_module.run_crew()
 
     assert capsys.readouterr().out == ""
-    assert calls == [("flow.yaml", None)]
+    assert calls == [(definition_path.resolve(), None)]