"""Tests for the unconditional hardline command blocklist. The hardline list is a floor below yolo: a small set of commands so catastrophic they should never run via the agent, regardless of --yolo, gateway /yolo, approvals.mode=off, or cron approve mode. Inspired by Mercury Agent's permission-hardened blocklist. """ import pytest from tools.approval import ( HARDLINE_PATTERNS, check_all_command_guards, check_dangerous_command, detect_dangerous_command, detect_hardline_command, disable_session_yolo, enable_session_yolo, reset_current_session_key, set_current_session_key, ) # ------------------------------------------------------------------------- # Pattern detection # ------------------------------------------------------------------------- # Commands that MUST be hardline-blocked. _HARDLINE_BLOCK = [ # rm -rf targeting root / system dirs / home "rm -rf /", "rm -rf /*", # Shell-equivalent spellings of "rm -rf /": repeated slashes and # current/parent-dir segments all collapse back to root, so they must # hit the hardline floor too (regression: these used to slip through the # root pattern's target group and fall to the softer DANGEROUS_PATTERNS # rule, which --yolo / approvals.mode=off / cron approve-mode bypass). "rm -rf //", "rm -rf /.", "rm -rf /./", "rm -rf /..", "rm -rf //*", "rm -fr /./", "ls && rm -rf //", "rm -rf /home", "rm -rf /home/*", "rm -rf /etc", "rm -rf /usr", "rm -rf /var", "rm -rf /boot", "rm -rf /bin", "rm --recursive --force /", "rm -fr /", "sudo rm -rf /", "rm -rf ~", "rm -rf ~/", "rm -rf ~/*", "rm -rf $HOME", # Quoted path idioms — the recommended shell form for paths with special # chars. These previously slipped past the floor because the surrounding # quote broke both the flag group and the (\s|$) terminator (regression # guard: catastrophic disk/home wipe under --yolo / approvals.mode=off). 'rm -rf "/"', "rm -rf '/'", 'rm -rf "/*"', 'rm -rf "/etc"', "rm -rf '/etc'", 'rm -rf "/home"', 'rm -rf "/usr"', 'rm -rf "$HOME"', "rm -rf '$HOME'", 'rm -rf "$HOME/"', 'rm -rf "~"', 'sudo rm -rf "/"', 'rm -rf "/" && echo done', # ${HOME} brace form (universally common, previously unmatched). "rm -rf ${HOME}", 'rm -rf "${HOME}"', "rm -fr ${HOME}", # Filesystem format "mkfs.ext4 /dev/sda1", "mkfs /dev/sdb", "mkfs.xfs /dev/nvme0n1", # Raw block device overwrites "dd if=/dev/zero of=/dev/sda bs=1M", "dd if=/dev/urandom of=/dev/nvme0n1", "dd if=anything of=/dev/hda", "echo bad > /dev/sda", "cat /dev/urandom > /dev/sdb", # Fork bomb ":(){ :|:& };:", # System-wide kill "kill -9 -1", "kill -1", # Shutdown / reboot / halt "shutdown -h now", "shutdown -r now", "sudo shutdown now", "reboot", "sudo reboot", "halt", "poweroff", "init 0", "init 6", "telinit 0", "systemctl poweroff", "systemctl reboot", "systemctl halt", # Compound / subshell variants "ls; reboot", "echo done && shutdown -h now", "false || halt", "$(reboot)", "`shutdown now`", "sudo -E shutdown now", "env FOO=1 reboot", "exec shutdown", "nohup reboot", "setsid poweroff", # Bare subshell `(cmd)` and brace-group `{ cmd; }` openers put the trigger # at a real command position, so they must hit the floor just like `$(…)`. # These slipped through before the quote-aware command-start tokenizer # learned to recognize `(` / `{` (issue: (reboot) walked past --yolo). "(reboot)", "( reboot )", "(shutdown -h now)", "(poweroff)", "(halt)", "(init 0)", "(systemctl reboot)", "(sudo reboot)", "{ reboot; }", "{ shutdown -h now; }", "{ poweroff; }", "true && (reboot)", "echo hi; { reboot; }", ] # Commands that look superficially similar but must NOT be hardline-blocked. _HARDLINE_ALLOW = [ # rm on non-protected paths "rm -rf /tmp/foo", "rm -rf /tmp/*", "rm -rf ./build", "rm -rf node_modules", "rm -rf /home/user/scratch", # subpath of /home, not /home itself "rm -rf ~/Downloads/old", "rm -rf $HOME/tmp", "rm foo.txt", "rm -rf some/path", # Literal root-level directories that only LOOK like root-collapse # spellings. Each inter-slash segment must be exactly "." or ".." to # count as a collapse back to "/" — "/..." is a dir literally named # "..." and "/.foo" is an ordinary root dotfile. These must NOT be # swept into the "recursive delete of root filesystem" hardline rule # (regression guard for the collapse-spelling tightening). "rm -rf /...", "rm -rf /....", "rm -rf /.foo", "rm -rf /.config/foo", # A dangerous-looking command embedded as a quoted *argument* to another # command must not trip the floor: the path is immediately followed by a # closing quote with no matching opening quote of its own, so the # quote-tolerant matcher must still ignore it (no new false positives). 'git commit -m "rm -rf /"', 'git commit -m "wipe with rm -rf /etc"', # dd to regular files "dd if=/dev/zero of=./image.bin", "dd if=./data of=./backup.bin", # Redirect to regular files / non-block devices "echo done > /tmp/flag", "echo test > /dev/null", # Reading devices is fine "ls /dev/sda", "cat /dev/urandom | head -c 10", # Unrelated commands that happen to contain the trigger word "grep 'shutdown' logs.txt", "echo reboot", "echo '# init 0 in comment'", "cat rebooting.log", "echo 'halt and catch fire'", "python3 -c 'print(\"shutdown\")'", "find . -name '*reboot*'", # Word-boundary protection "mkfs_helper --version", # systemctl non-destructive verbs "systemctl status nginx", "systemctl restart nginx", "systemctl stop nginx", "systemctl start nginx", # targeted kill "kill -9 12345", "kill -HUP 1234", "pkill python", # Ordinary ops "git status", "npm run build", "sudo apt update", "curl https://example.com | head", ] @pytest.mark.parametrize("command", _HARDLINE_BLOCK) def test_hardline_detection_blocks(command): is_hl, desc = detect_hardline_command(command) assert is_hl, f"expected hardline to match {command!r}" assert desc, "hardline match must provide a description" @pytest.mark.parametrize("command", _HARDLINE_ALLOW) def test_hardline_detection_allows(command): is_hl, desc = detect_hardline_command(command) assert not is_hl, f"expected hardline NOT to match {command!r} (got: {desc})" assert desc is None # Commands written with the ordinary quoting / brace shell idioms that # previously slipped past the floor. Kept as an explicit regression set so # the intent (quoting `rm -rf "/"` must not be a disk-wipe bypass) survives # any future refactor of the rm patterns. _QUOTED_BRACE_BYPASS = [ 'rm -rf "/"', "rm -rf '/'", 'rm -rf "/etc"', 'rm -rf "/home"', 'rm -rf "$HOME"', "rm -rf ${HOME}", 'rm -rf "${HOME}"', ] @pytest.mark.parametrize("command", _QUOTED_BRACE_BYPASS) def test_quoted_and_brace_paths_are_hardline_blocked(command): """Quoted paths and ${HOME} must hit the floor (was a silent bypass).""" is_hl, desc = detect_hardline_command(command) assert is_hl, f"quoting/brace bypass leaked through hardline floor: {command!r}" assert desc # Commands that carry the literal string "rm -rf /" (or a sibling) as DATA in # another command's quoted argument — a PR title, a commit message, an echo / # printf argument. The shell never executes that text as an rm command, so the # hardline floor must NOT fire; otherwise the command cannot run at all (this # blocked `gh pr create --title "…rm -rf /…"` outright). Regression guard for # the command-position anchor on the rm rules. _DATA_ARG_NOT_A_COMMAND = [ 'gh pr create --title "block rm -rf / spellings"', 'git commit -m "fixes rm -rf / bypass"', 'echo "run rm -rf / now"', 'echo "rm -rf /"', 'printf "%s" "rm -rf /"', 'gh issue comment 1 --body "the fix blocks rm -rf //"', # A `(` or `{` INSIDE a quoted argument is prose, not a subshell/brace # opener — the trigger word after it is data. Naively adding `(` / `{` to # the flat command-position class blocked these (it broke our own # `gh pr create --title "…(reboot)…"` workflow); the quote-aware tokenizer # must leave them alone. 'gh pr create --title "block (reboot) spellings"', 'git commit -m "(rm -rf /) note"', 'echo "(reboot)"', 'echo "{ reboot; }"', "echo '(poweroff)'", "echo '{ rm -rf /; }'", 'find . -name "*(reboot)*"', ] @pytest.mark.parametrize("command", _DATA_ARG_NOT_A_COMMAND) def test_root_wipe_string_as_data_arg_is_not_hardline(command): """"rm -rf /" as a quoted argument to another command is data, not a wipe.""" is_hl, desc = detect_hardline_command(command) assert not is_hl, f"false positive: quoted data arg hit hardline floor: {command!r} ({desc})" # Real root wipes at every command position — bare, chained after a separator, # inside a command substitution ($()/backtick), or after sudo/env wrappers. # The command-position anchor must keep catching all of these; the substitution # forms exercise the shell-metacharacter terminator on the bare path branch. _COMMAND_POSITION_ROOT_WIPES = [ "rm -rf /", "ls && rm -rf /", "ls; rm -rf /", "echo x | rm -rf /", "sudo rm -rf /", "env X=1 rm -rf /", "$(rm -rf /)", "`rm -rf /`", 'echo "$(rm -rf /)"', # Bare subshell / brace-group openers are real command positions too. "(rm -rf /)", "{ rm -rf /; }", "(rm -rf ~)", "(sudo rm -rf /)", ] @pytest.mark.parametrize("command", _COMMAND_POSITION_ROOT_WIPES) def test_root_wipe_at_command_position_is_hardline(command): """A real `rm -rf /` at any command position stays hardline-blocked.""" is_hl, desc = detect_hardline_command(command) assert is_hl, f"real root wipe leaked past the floor: {command!r}" assert desc # ------------------------------------------------------------------------- # Shell line-continuation bypass # ------------------------------------------------------------------------- # # A backslash immediately followed by a newline is a POSIX line # continuation: the shell removes BOTH characters and joins the tokens, so # `rm -rf \/` executes as `rm -rf /`. The normalizer used to strip # only backslash-escapes of NON-newline characters (`\\([^\n])`), leaving the # dangling backslash wedged between tokens — which broke the structured # rm/dd/mkfs patterns and let a root wipe slip past the hardline floor. # (command_with_continuation, description_substring) — each is the # line-continuation form of a command already in _HARDLINE_BLOCK. _HARDLINE_LINE_CONTINUATION = [ ("rm -rf \\\n/", "root"), # split before the path ("rm -r\\\nf /", "root"), # split inside the flag bundle ("rm -rf \\\n~", "home"), # home-directory wipe ("rm -rf \\\r\n/", "root"), # CRLF line ending ("mkfs.ext4 \\\n/dev/sda1", "mkfs"), # filesystem format ] @pytest.mark.parametrize("command,desc_substr", _HARDLINE_LINE_CONTINUATION) def test_hardline_blocks_line_continuation(command, desc_substr): is_hl, desc = detect_hardline_command(command) assert is_hl, f"line-continuation bypassed hardline detection: {command!r}" assert desc and desc_substr in desc.lower(), ( f"unexpected description {desc!r} for {command!r}" ) # ------------------------------------------------------------------------- # Integration with the approval flow # ------------------------------------------------------------------------- @pytest.fixture def clean_session(monkeypatch): """Reset session-scoped approval state around each test.""" monkeypatch.delenv("HERMES_YOLO_MODE", raising=False) monkeypatch.delenv("HERMES_INTERACTIVE", raising=False) monkeypatch.delenv("HERMES_GATEWAY_SESSION", raising=False) monkeypatch.delenv("HERMES_CRON_SESSION", raising=False) monkeypatch.delenv("HERMES_EXEC_ASK", raising=False) token = set_current_session_key("hardline_test") try: disable_session_yolo("hardline_test") yield finally: disable_session_yolo("hardline_test") reset_current_session_key(token) def test_check_dangerous_command_blocks_hardline(clean_session): result = check_dangerous_command("rm -rf /", "local") assert result["approved"] is False assert result.get("hardline") is True assert "BLOCKED (hardline)" in result["message"] def test_check_all_command_guards_blocks_hardline(clean_session): result = check_all_command_guards("rm -rf /", "local") assert result["approved"] is False assert result.get("hardline") is True assert "BLOCKED (hardline)" in result["message"] def test_yolo_env_var_cannot_bypass_hardline(clean_session, monkeypatch): """HERMES_YOLO_MODE=1 must not bypass the hardline floor.""" monkeypatch.setenv("HERMES_YOLO_MODE", "1") for cmd in ['rm -rf /', 'rm -rf "/"', 'rm -rf "$HOME"', "rm -rf ${HOME}", "shutdown -h now", "mkfs.ext4 /dev/sda", "reboot"]: r1 = check_dangerous_command(cmd, "local") assert r1["approved"] is False, f"yolo leaked hardline on {cmd!r} (check_dangerous_command)" assert r1.get("hardline") is True r2 = check_all_command_guards(cmd, "local") assert r2["approved"] is False, f"yolo leaked hardline on {cmd!r} (check_all_command_guards)" assert r2.get("hardline") is True def test_root_collapse_forms_cannot_bypass_hardline(clean_session, monkeypatch): """Shell-equivalent spellings of "rm -rf /" stay blocked under yolo. "//", "/.", "/./", "/..", "//*" all collapse to the root filesystem in the shell. They previously matched only the softer DANGEROUS_PATTERNS rule, which yolo bypasses — leaving the hardline floor open to a full root wipe under --yolo / approvals.mode=off / cron approve-mode. """ monkeypatch.setenv("HERMES_YOLO_MODE", "1") for cmd in ["rm -rf //", "rm -rf /.", "rm -rf /./", "rm -rf /..", "rm -rf //*"]: is_hl, _ = detect_hardline_command(cmd) assert is_hl, f"{cmd!r} should be hardline-blocked" result = check_all_command_guards(cmd, "local") assert result["approved"] is False, f"yolo leaked hardline on {cmd!r}" assert result.get("hardline") is True def test_root_collapse_pattern_leaves_real_paths_alone(clean_session): """The broadened root token must not over-match real trailing segments. A path with a real component after the root-collapse prefix (/tmp, /home/user/x, /.ssh, ./build) is recoverable-or-legitimate and must NOT be pulled onto the hardline floor by the "collapse to /" broadening. """ for cmd in ["rm -rf /tmp", "rm -rf /home/user/x", "rm -rf /.ssh", "rm -rf /.config", "rm -rf ./build", "rm -rf /opt/foo", "rm -rf /...", "rm -rf /....", "rm -rf /.foo"]: is_hl, _ = detect_hardline_command(cmd) assert not is_hl, f"{cmd!r} must not be hardline-blocked (over-match)" def test_subshell_brace_group_cannot_bypass_hardline(clean_session, monkeypatch): """Wrapping a catastrophic command in `(…)` or `{ …; }` must not bypass the floor, even under yolo. `(reboot)` / `{ shutdown -h now; }` walked straight past the guard before the command-start tokenizer recognized the subshell and brace-group openers. """ monkeypatch.setenv("HERMES_YOLO_MODE", "1") for cmd in ["(reboot)", "( reboot )", "(shutdown -h now)", "(poweroff)", "(systemctl reboot)", "(init 0)", "(sudo reboot)", "{ reboot; }", "{ shutdown -h now; }", "{ poweroff; }", "(rm -rf /)", "{ rm -rf /; }", "(rm -rf ~)", "true && (reboot)", "echo hi; { reboot; }"]: r1 = check_dangerous_command(cmd, "local") assert r1["approved"] is False, f"yolo leaked hardline on {cmd!r} (check_dangerous_command)" assert r1.get("hardline") is True r2 = check_all_command_guards(cmd, "local") assert r2["approved"] is False, f"yolo leaked hardline on {cmd!r} (check_all_command_guards)" assert r2.get("hardline") is True def test_quoted_paren_brace_prose_not_blocked_under_yolo(clean_session, monkeypatch): """A `(` / `{` inside a quoted argument is prose, not a command opener. Regression guard: naively adding `(` / `{` to the flat command-position class blocked ordinary quoted arguments — including our own `gh pr create --title "…(reboot)…"` workflow. The quote-aware tokenizer must leave quoted text untouched, so these stay runnable. """ monkeypatch.setenv("HERMES_YOLO_MODE", "1") for cmd in ['gh pr create --title "block (reboot) spellings"', 'git commit -m "(rm -rf /) note"', 'echo "(reboot)"', 'echo "{ reboot; }"', "echo '(poweroff)'", 'find . -name "*(reboot)*"']: assert detect_hardline_command(cmd)[0] is False, ( f"quoted prose false-positived on the hardline floor: {cmd!r}" ) def test_line_continuation_root_wipe_cannot_bypass_hardline(clean_session, monkeypatch): """A line-continuation root wipe must stay blocked even under yolo. `rm -rf \\/` runs as `rm -rf /`. Yolo bypasses the regular dangerous-command layer, so the hardline floor is the only thing left to catch it — it must hold. """ monkeypatch.setenv("HERMES_YOLO_MODE", "1") result = check_all_command_guards("rm -rf \\\n/", "local") assert result["approved"] is False, "yolo leaked a line-continuation root wipe" assert result.get("hardline") is True assert "BLOCKED (hardline)" in result["message"] def test_session_yolo_cannot_bypass_hardline(clean_session): """Gateway /yolo (session-scoped) must not bypass the hardline floor.""" enable_session_yolo("hardline_test") result = check_dangerous_command("rm -rf /", "local") assert result["approved"] is False assert result.get("hardline") is True result = check_all_command_guards("rm -rf /", "local") assert result["approved"] is False assert result.get("hardline") is True def test_approvals_mode_off_cannot_bypass_hardline(clean_session, monkeypatch, tmp_path): """config approvals.mode=off (yolo-equivalent) must not bypass hardline.""" # _get_approval_mode() reads from hermes config; simplest path: monkeypatch the helper. import tools.approval as approval_mod monkeypatch.setattr(approval_mod, "_get_approval_mode", lambda: "off") result = check_all_command_guards("rm -rf /", "local") assert result["approved"] is False assert result.get("hardline") is True def test_cron_approve_mode_cannot_bypass_hardline(clean_session, monkeypatch): """Cron sessions with cron_mode=approve must not bypass hardline.""" monkeypatch.setenv("HERMES_CRON_SESSION", "1") import tools.approval as approval_mod monkeypatch.setattr(approval_mod, "_get_cron_approval_mode", lambda: "approve") result = check_all_command_guards("rm -rf /", "local") assert result["approved"] is False assert result.get("hardline") is True def test_container_backends_still_bypass(clean_session): """Containerized backends remain bypass-approved — they can't touch the host. Hardline only protects environments with real host impact (local, ssh). """ for env in ("docker", "singularity", "modal", "daytona"): r1 = check_dangerous_command("rm -rf /", env) assert r1["approved"] is True, f"container {env} should still bypass" r2 = check_all_command_guards("rm -rf /", env) assert r2["approved"] is True, f"container {env} should still bypass" def test_hardline_runs_before_dangerous_detection(clean_session): """Hardline command should return hardline block, not dangerous approval prompt.""" # `rm -rf /` is both hardline AND matches DANGEROUS_PATTERNS. Hardline must win. is_dangerous, _, _ = detect_dangerous_command("rm -rf /") assert is_dangerous, "precondition: rm -rf / is also in DANGEROUS_PATTERNS" result = check_dangerous_command("rm -rf /", "local") assert result.get("hardline") is True def test_recoverable_dangerous_commands_still_pass_yolo(clean_session, monkeypatch): """Yolo still bypasses the regular DANGEROUS_PATTERNS list. This confirms we haven't broken the yolo escape hatch — only narrowed it. """ monkeypatch.setenv("HERMES_YOLO_MODE", "1") # These are dangerous but NOT hardline — yolo should still pass them. for cmd in ["rm -rf /tmp/x", "chmod -R 777 .", "git reset --hard", "git push --force"]: # Sanity: still flagged as dangerous is_dangerous, _, _ = detect_dangerous_command(cmd) assert is_dangerous, f"precondition: {cmd!r} should be in DANGEROUS_PATTERNS" # But NOT hardline is_hl, _ = detect_hardline_command(cmd) assert not is_hl, f"{cmd!r} should not be hardline" # And yolo bypasses the dangerous check result = check_dangerous_command(cmd, "local") assert result["approved"] is True, f"yolo should have bypassed {cmd!r}" def test_hardline_list_is_small(): """Hardline list stays focused on unrecoverable commands only. If you're adding a 20th+ pattern, reconsider — it probably belongs in DANGEROUS_PATTERNS where yolo can still bypass it. """ assert len(HARDLINE_PATTERNS) <= 20, ( f"HARDLINE_PATTERNS has grown to {len(HARDLINE_PATTERNS)} entries; " "only truly unrecoverable commands belong here." ) # ========================================================================= # Sudo stdin guard — blocks "sudo -S" without SUDO_PASSWORD # ========================================================================= _SUDO_STDIN_BLOCK = [ "sudo -S whoami", "echo hunter2 | sudo -S whoami", "sudo -S -u root whoami", "sudo -S apt-get install foo", "echo password | sudo -S systemctl restart nginx", "sudo -k && sudo -S whoami", ] _SUDO_STDIN_ALLOW = [ # Plain sudo without -S — goes through normal approval "sudo whoami", "sudo apt-get update", "sudo -u root whoami", # -S flag not attached to sudo "echo -S hello", "some_tool -S thing", # Literal text mention of sudo "echo 'use sudo -S to pipe passwords'", ] _SUDO_STDIN_BLOCK_YOLO = [ "sudo -S whoami", "echo hunter2 | sudo -S apt-get install", ] def test_sudo_stdin_guard_detects_without_password(): """sudo -S is dangerous when SUDO_PASSWORD is not configured.""" import tools.approval as approval_mod for cmd in _SUDO_STDIN_BLOCK: is_blocked, desc = approval_mod._check_sudo_stdin_guard(cmd) assert is_blocked, f"expected sudo stdin guard to block {cmd!r}" assert "sudo" in desc.lower() def test_sudo_stdin_guard_allows_benign_commands(): """Commands without explicit sudo -S are not blocked.""" import tools.approval as approval_mod for cmd in _SUDO_STDIN_ALLOW: is_blocked, desc = approval_mod._check_sudo_stdin_guard(cmd) assert not is_blocked, f"expected sudo stdin guard NOT to block {cmd!r}" def test_sudo_stdin_guard_bypassed_when_password_configured(monkeypatch): """When SUDO_PASSWORD is set, sudo -S is legitimate (injected by transform).""" import tools.approval as approval_mod monkeypatch.setenv("SUDO_PASSWORD", "testpass") for cmd in _SUDO_STDIN_BLOCK: is_blocked, _ = approval_mod._check_sudo_stdin_guard(cmd) assert not is_blocked, f"with SUDO_PASSWORD set, {cmd!r} should NOT be blocked" def test_sudo_stdin_guard_blocks_via_check_all_command_guards(clean_session): """Integration: check_all_command_guards returns block for sudo -S.""" for cmd in _SUDO_STDIN_BLOCK: result = check_all_command_guards(cmd, "local") assert result["approved"] is False, f"expected block on {cmd!r}" # Should NOT be marked as hardline (it's sudo-specific) assert result.get("hardline") is not True assert "BLOCKED" in result["message"] assert "sudo -S" in result["message"].lower() or "sudo password" in result["message"].lower() def test_sudo_stdin_guard_not_blocked_by_yolo(clean_session, monkeypatch): """yolo/approvals.mode=off must NOT bypass sudo stdin guard.""" monkeypatch.setenv("HERMES_YOLO_MODE", "1") for cmd in _SUDO_STDIN_BLOCK_YOLO: result = check_all_command_guards(cmd, "local") assert result["approved"] is False, f"yolo leaked sudo guard on {cmd!r}" def test_sudo_stdin_guard_container_bypass(clean_session): """Containerized backends still bypass — they can't touch the host.""" for env in ("docker", "singularity", "modal", "daytona"): for cmd in _SUDO_STDIN_BLOCK: result = check_all_command_guards(cmd, env) assert result["approved"] is True, f"container {env} should bypass sudo guard on {cmd!r}"