Files
roboco/tests/unit/runtime/test_cc_lockdown.py
T
3787d15524 fix(agents): block subagent spawning at the Claude Code level (disallow Task) (#377)
The fleet-wide subagent ban was implemented as an allowlist omission, but Task
is a default-permitted Claude Code built-in — an allowlist auto-approves, it
does not restrict. Under permission_mode="dontAsk" (intake/secretary SDK) and
defaultMode="bypassPermissions" (fleet), Task ran regardless and can_use_tool
was never invoked for it, so every Claude-path agent could still spawn
subagents despite allows_subagent=False. Only the grok path blocked it.

Explicitly disallow the subagent tool at every Claude-path spawn point:
disallowed_tools=["Task"] on the intake and secretary SDK drivers, and "Task"
in the fleet settings.json base_deny (an explicit deny applies even under
bypassPermissions). This mirrors the grok path's --disallowed-tools Agent.

Pins the ban in test_cc_lockdown.py (fleet settings deny Task) and a new
test_sdk_driver_subagent_ban.py (intake + secretary options disallow Task).

Co-authored-by: Renn F <rennf93@users.noreply.github.com>
2026-07-10 02:37:12 +02:00

233 lines
9.2 KiB
Python

"""Claude Code capability lockdown.
Two independent tightenings against the shared Claude Code harness state:
1. The host's ~/.claude (OAuth credential store) and ~/.claude.json are
bind-mounted read-write into EVERY agent container (the shared
subscription auth every spawned agent uses — see
AgentOrchestrator._build_mount_args). No role's job requires the LLM to
read its own harness's credentials, so the generated settings.json must
deny the native Read tool from the two files that carry them.
2. `--disable-slash-commands` must accompany every container spawn: skills
resolve independently of the `--tools` built-in allowlist (Anthropic's
own `--bare` docs note skills still resolve via `/skill-name` even with
everything else disabled), so if the shared `~/.claude` mount ever
carries personal skills/plugins they must not become callable inside an
agent's session.
"""
from __future__ import annotations
import json
from pathlib import Path
from unittest.mock import patch
from roboco.models.runtime import OrchestratorAgentConfig, SpawnGitContext
from roboco.runtime.orchestrator import AgentOrchestrator
_WS = "/data/workspaces/roboco-api/backend/be-dev-1"
_CELL = "/data/workspaces/roboco-api/backend"
def _orch() -> AgentOrchestrator:
with patch.object(AgentOrchestrator, "__init__", return_value=None):
return AgentOrchestrator.__new__(AgentOrchestrator)
def _make_dev_config() -> OrchestratorAgentConfig:
return OrchestratorAgentConfig(
agent_id="be-dev-1",
blueprint_path=Path("/app/agents/blueprints/be-dev-1.md"),
model="sonnet",
mcp_config_path=Path("/app/mcp-config.json"),
git_context=SpawnGitContext(
project_slug="roboco-api",
branch_name="feature/backend/TASK0001",
),
)
def _build_image_args() -> list[str]:
cmd: list[str] = []
with patch(
"roboco.runtime.orchestrator._resolve_agent_cli_model",
return_value="claude-sonnet-5",
):
AgentOrchestrator._append_image_and_claude_args(cmd, _make_dev_config(), None)
return cmd
class TestSharedClaudeCredentialsDenied:
"""Every role's generated settings.json blocks the Read tool from the
shared ~/.claude OAuth credential store."""
def test_developer_settings_deny_claude_credentials(self) -> None:
orch = _orch()
path = orch._generate_agent_settings(
agent_id="be-dev-1",
role="developer",
workspace_path=_WS,
cell_workspace_path=_CELL,
)
deny = json.loads(Path(path).read_text())["permissions"]["deny"]
assert "Read(//home/agent/.claude/.credentials.json)" in deny, deny
assert "Read(//home/agent/.claude.json)" in deny, deny
def test_qa_settings_also_deny_claude_credentials(self) -> None:
"""Not just the writer roles — a read-only role gets the same base_deny."""
orch = _orch()
path = orch._generate_agent_settings(
agent_id="be-qa",
role="qa",
workspace_path=_WS,
cell_workspace_path=_CELL,
)
deny = json.loads(Path(path).read_text())["permissions"]["deny"]
assert "Read(//home/agent/.claude/.credentials.json)" in deny, deny
assert "Read(//home/agent/.claude.json)" in deny, deny
def test_deny_uses_absolute_double_slash_form(self) -> None:
"""Per the #167 gotcha: a single leading / resolves against the
settings.json project root, not the container filesystem root — an
absolute container path deny needs the // form or it silently never
matches."""
orch = _orch()
path = orch._generate_agent_settings(
agent_id="be-dev-1",
role="developer",
workspace_path=_WS,
cell_workspace_path=_CELL,
)
deny = json.loads(Path(path).read_text())["permissions"]["deny"]
claude_denies = [d for d in deny if d.startswith("Read(") and ".claude" in d]
assert claude_denies, deny
for entry in claude_denies:
inner = entry[entry.index("(") + 1 :]
assert inner.startswith("//"), f"must use // absolute form: {entry}"
class TestSubagentBanned:
"""Every role's settings.json denies the `Task` subagent tool.
`Task` is a default-permitted Claude Code built-in; under
defaultMode=bypassPermissions the manifest/allowlist omission does NOT
remove it — only an explicit `permissions.deny` entry does. Without this
the fleet-wide subagent ban (CEO, 2026-07-09) is unenforced on the Claude
path (the grok path already blocks it via `--disallowed-tools Agent`).
"""
def test_developer_settings_deny_task(self) -> None:
orch = _orch()
path = orch._generate_agent_settings(
agent_id="be-dev-1",
role="developer",
workspace_path=_WS,
cell_workspace_path=_CELL,
)
deny = json.loads(Path(path).read_text())["permissions"]["deny"]
assert "Task" in deny, deny
def test_read_only_role_also_denies_task(self) -> None:
"""A read-only role (pr_reviewer, the top prompt-injection target)
gets the same base_deny → no subagent escape hatch."""
orch = _orch()
path = orch._generate_agent_settings(
agent_id="be-pr-reviewer",
role="pr_reviewer",
workspace_path=_WS,
cell_workspace_path=_CELL,
)
deny = json.loads(Path(path).read_text())["permissions"]["deny"]
assert "Task" in deny, deny
class TestSlashCommandsDisabled:
"""--disable-slash-commands accompanies every container agent spawn."""
def test_cmd_contains_disable_slash_commands_flag(self) -> None:
cmd = _build_image_args()
assert "--disable-slash-commands" in cmd, (
f"--disable-slash-commands missing from spawn cmd — skills resolve "
f"independently of --tools, so a contaminated shared ~/.claude mount "
f"could still expose host skills/plugins. Full cmd: {cmd}"
)
def test_tools_flag_still_present(self) -> None:
"""The new flag must not crowd out or replace the existing --tools cap."""
cmd = _build_image_args()
assert "--tools" in cmd
idx = cmd.index("--tools")
assert cmd[idx + 1] == "Read,Write,Edit,Bash,Grep,Glob,TodoWrite"
class TestFableModeHooksInjection:
"""Fable-mode hooks are additive to settings.json, gated by the flag."""
def test_fable_hooks_absent_when_flag_disabled(self) -> None:
with patch("roboco.config.settings.fable_mode_enabled", False):
orch = _orch()
path = orch._generate_agent_settings(
agent_id="be-dev-1",
role="developer",
workspace_path=_WS,
cell_workspace_path=_CELL,
)
hooks = json.loads(Path(path).read_text())["hooks"]
assert "SubagentStop" not in hooks
stop_cmds = [h["command"] for g in hooks["Stop"] for h in g["hooks"]]
assert not any("fable" in c for c in stop_cmds)
def test_fable_hooks_present_when_flag_enabled(self) -> None:
with patch("roboco.config.settings.fable_mode_enabled", True):
orch = _orch()
path = orch._generate_agent_settings(
agent_id="be-dev-1",
role="developer",
workspace_path=_WS,
cell_workspace_path=_CELL,
)
hooks = json.loads(Path(path).read_text())["hooks"]
stop_cmds = [h["command"] for g in hooks["Stop"] for h in g["hooks"]]
assert stop_cmds[-1] == "/app/scripts/fable-stop-gate-hook.sh" # appended last
assert stop_cmds[0] == "/app/scripts/stop-hook.sh" # RoboCo's check still first
subagent_cmds = [
h["command"] for g in hooks["SubagentStop"] for h in g["hooks"]
]
assert subagent_cmds == ["/app/scripts/fable-stop-gate-hook.sh subagent"]
pretool_bash = [
h["command"]
for g in hooks["PreToolUse"]
if g.get("matcher") == "Bash"
for h in g["hooks"]
]
assert "/app/scripts/bash-guard-hook.sh" in pretool_bash # existing guard kept
assert "/app/scripts/fable-bash-discipline-hook.sh" in pretool_bash
posttool_bash = [
h["command"]
for g in hooks["PostToolUse"]
if g.get("matcher") == "Bash"
for h in g["hooks"]
]
assert posttool_bash == ["/app/scripts/fable-honesty-nudge-hook.sh"] # new
def test_fable_hooks_off_leaves_hooks_dict_unchanged(self) -> None:
"""Regression guard: flag-off output equals a captured pre-Phase-2 baseline."""
with patch("roboco.config.settings.fable_mode_enabled", False):
orch = _orch()
path = orch._generate_agent_settings(
agent_id="be-dev-1",
role="developer",
workspace_path=_WS,
cell_workspace_path=_CELL,
)
hooks = json.loads(Path(path).read_text())["hooks"]
assert set(hooks.keys()) == {
"SessionStart",
"PreToolUse",
"PostToolUse",
"Stop",
"UserPromptSubmit",
"PreCompact",
"SessionEnd",
}