atlas-iac/testing/tests/test_hermes_execution_pool_scm_tampering.py

"""SCM checkout ownership and private-baseline corruption probes."""

from __future__ import annotations

import sys
import subprocess
from pathlib import Path

import pytest


ROOT = Path(__file__).parents[2]
sys.path[:0] = [
    str(ROOT / "services/hermes/scripts"),
    str(ROOT / "services/hermes/scm-common/scripts"),
]

import execution_pool_protocol as protocol  # noqa: E402
import execution_pool_scm as scm  # noqa: E402
from testing.tests.test_hermes_execution_pool_mediator import (  # noqa: E402
    KEY,
    assignment,
    init_checkout,
)


def test_checkout_and_submit_reject_unmanaged_or_corrupt_private_state(
    tmp_path, monkeypatch
):
    monkeypatch.setattr(scm, "WORKSPACE_ROOT", tmp_path / "workspace")
    monkeypatch.setattr(scm, "SCM_ROOT", tmp_path / "state")
    monkeypatch.setattr(scm, "ORDINAL", 0)
    destination = scm.workspace_path(assignment())
    destination.mkdir(parents=True)
    (destination / "owner-file").write_text("preserve")
    boundary = scm.Boundary(KEY)
    with pytest.raises(protocol.ProtocolError, match="non-empty"):
        boundary.checkout(assignment())

    (destination / "owner-file").unlink()

    def clone_with_empty_failure(*arguments, **_kwargs):
        if arguments[0] == "clone" and arguments[4] == "wt/t_deadbeef":
            destination.mkdir(parents=True, exist_ok=True)
            raise RuntimeError("missing")
        if arguments[0] == "clone":
            (destination / ".git").mkdir(parents=True)
        return ""

    monkeypatch.setattr(scm, "_run", clone_with_empty_failure)
    monkeypatch.setattr(scm, "_workspace_identity", lambda *_a: "a" * 40)
    assert boundary.checkout(assignment())["baseline_sha"] == "a" * 40

    protocol.atomic_json(scm._state_path(assignment()), {"baseline_sha": "bad"})
    with pytest.raises(protocol.ProtocolError, match="baseline"):
        boundary.submit(assignment(), {})


def test_scm_identity_is_data_only_and_supports_packed_refs(tmp_path):
    checkout = tmp_path / "checkout"
    subprocess.run(["git", "init", "-q", str(checkout)], check=True)
    subprocess.run(
        [
            "git", "-C", str(checkout), "remote", "add", "origin",
            "https://scm.bstein.dev/titan/atlas-iac.git",
        ],
        check=True,
    )
    subprocess.run(
        [
            "git", "-C", str(checkout), "remote", "add", "hermes-broker",
            scm._broker_repo("atlas-iac"),
        ],
        check=True,
    )
    subprocess.run(
        [
            "git", "-C", str(checkout), "checkout", "-qb",
            "feature/hermes-safe-pool",
        ],
        check=True,
    )
    subprocess.run(
        ["git", "-C", str(checkout), "config", "user.email", "a@b.c"],
        check=True,
    )
    subprocess.run(
        ["git", "-C", str(checkout), "config", "user.name", "Test"],
        check=True,
    )
    (checkout / "tracked").write_text("safe\n")
    subprocess.run(["git", "-C", str(checkout), "add", "tracked"], check=True)
    subprocess.run(
        ["git", "-C", str(checkout), "commit", "-qm", "initial"], check=True
    )
    expected = subprocess.check_output(
        ["git", "-C", str(checkout), "rev-parse", "HEAD"], text=True
    ).strip()
    subprocess.run(
        ["git", "-C", str(checkout), "pack-refs", "--all"], check=True
    )
    assert scm._workspace_identity(
        checkout,
        "atlas-iac",
        "feature/hermes-safe-pool",
    ) == expected
    (checkout / ".git/refs/heads/feature").mkdir(parents=True)
    (checkout / ".git/refs/heads/feature/hermes-safe-pool").symlink_to(
        "/etc/passwd"
    )
    with pytest.raises(protocol.ProtocolError, match="symlink"):
        scm._workspace_identity(
            checkout,
            "titan-iac",
            "feature/hermes-safe-pool",
        )


def test_scm_paths_and_identity_reject_symlink_and_git_tampering(
    tmp_path, monkeypatch
):
    workspace = tmp_path / "workspace"
    workspace.mkdir()
    workspace_link = tmp_path / "workspace-link"
    workspace_link.symlink_to(workspace, target_is_directory=True)
    monkeypatch.setattr(scm, "WORKSPACE_ROOT", workspace_link)
    with pytest.raises(protocol.ProtocolError, match="root"):
        scm.workspace_path(assignment())

    monkeypatch.setattr(scm, "WORKSPACE_ROOT", workspace)
    (workspace / "runs").mkdir()
    (workspace / "runs/metis").symlink_to(tmp_path, target_is_directory=True)
    with pytest.raises(protocol.ProtocolError, match="parent"):
        scm.workspace_path(assignment())

    state = tmp_path / "state"
    state.mkdir()
    monkeypatch.setattr(scm, "SCM_ROOT", state)
    expected_state = state / "metis-t_deadbeef-42.json"
    expected_state.symlink_to("/etc/passwd")
    with pytest.raises(protocol.ProtocolError, match="state"):
        scm._state_path(assignment())

    checkout = tmp_path / "checkout"
    checkout.mkdir()
    with pytest.raises(protocol.ProtocolError, match="metadata"):
        scm._workspace_identity(checkout, "metis", "wt/t_deadbeef")
    init_checkout(checkout)
    subprocess.run(
        [
            "git", "-C", str(checkout), "remote", "set-url", "origin",
            "https://evil.example/repo.git",
        ],
        check=True,
    )
    with pytest.raises(protocol.ProtocolError, match="origin"):
        scm._workspace_identity(checkout, "metis", "wt/t_deadbeef")
    subprocess.run(
        [
            "git", "-C", str(checkout), "remote", "set-url", "origin",
            "https://scm.bstein.dev/titan/metis.git",
        ],
        check=True,
    )
    subprocess.run(
        [
            "git", "-C", str(checkout), "remote", "set-url", "hermes-broker",
            "http://hermes-scm-broker.hermes-scm.svc.cluster.local:9081/"
            "git/atlas/soteria.git",
        ],
        check=True,
    )
    with pytest.raises(protocol.ProtocolError, match="broker remote"):
        scm._workspace_identity(checkout, "metis", "wt/t_deadbeef")
    subprocess.run(
        [
            "git", "-C", str(checkout), "remote", "set-url", "hermes-broker",
            "http://hermes-scm-broker.hermes-scm.svc.cluster.local:9081/"
            "git/atlas/metis.git",
        ],
        check=True,
    )
    with pytest.raises(protocol.ProtocolError, match="branch"):
        scm._workspace_identity(checkout, "metis", "review/other")
    monkeypatch.setattr(
        scm,
        "_run",
        lambda *arguments, **_kwargs: {
            "remote": (
                "http://hermes-scm-broker.hermes-scm.svc.cluster.local:9081/"
                "git/atlas/metis.git"
                if arguments[-1] == "hermes-broker"
                else "https://scm.bstein.dev/titan/metis.git"
            ),
            "symbolic-ref": "wt/t_deadbeef",
            "rev-parse": "invalid",
        }[arguments[0]],
    )
    with pytest.raises(protocol.ProtocolError, match="HEAD"):
        scm._workspace_identity(checkout, "metis", "wt/t_deadbeef")