Coverage for agentos/security/sandbox.py: 44%
210 statements
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1"""
2AgentOS Sandbox — Secure Code Execution Sandbox
3━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
5Production-grade code execution sandbox with:
7 - Resource limits (CPU time, memory, disk, network)
8 - Timeout enforcement
9 - Process isolation (subprocess-based)
10 - Dangerous import/module blacklisting
11 - Output size limits
12 - Audit logging for every execution
14Architecture:
15 SandboxPolicy → defines resource limits and restrictions
16 SandboxExecutor → executes code in isolated subprocess
17 SandboxResult → immutable execution result
18"""
20from __future__ import annotations
22import builtins
23import os
24import resource
25import subprocess
26import sys
27import tempfile
28import time
29import traceback
30from dataclasses import dataclass, field
31from enum import StrEnum
32from typing import Any
34# ---------------------------------------------------------------------------
35# Sandbox Policy
36# ---------------------------------------------------------------------------
39class SecurityLevel(StrEnum):
40 """Security level determines which restrictions apply."""
42 RESTRICTED = "restricted" # Max restrictions, no network/disk
43 STANDARD = "standard" # Reasonable limits for most use cases
44 RELAXED = "relaxed" # Minimal restrictions, trusted code only
47# Dangerous modules and builtins to block
48DANGEROUS_MODULES: set[str] = {
49 "os",
50 "subprocess",
51 "shlex",
52 "sys",
53 "ctypes",
54 "socket",
55 "http",
56 "requests",
57 "urllib",
58 "multiprocessing",
59 "threading",
60 "concurrent.futures",
61 "importlib",
62 "pkgutil",
63 "pkg_resources",
64 "pickle",
65 "marshal",
66 "shelve",
67 "pathlib",
68 "shutil",
69 "glob",
70 "fnmatch",
71 "signal",
72 "atexit",
73 "code",
74 "codeop",
75 "compileall",
76 "pty",
77 "fcntl",
78 "tty",
79 "termios",
80 "webbrowser",
81}
83DANGEROUS_BUILTINS: set[str] = {
84 "__import__",
85 "compile",
86 "eval",
87 "exec",
88 "open",
89 "input",
90 "breakpoint",
91 "globals",
92 "locals",
93 "vars",
94 "getattr",
95 "setattr",
96 "delattr",
97 "type",
98 "issubclass",
99 "isinstance",
100 "memoryview",
101 "bytearray",
102}
105@dataclass
106class SandboxPolicy:
107 """Resource limits and restrictions for sandboxed execution."""
109 # Resource limits
110 max_cpu_time_seconds: float = 30.0
111 max_memory_mb: int = 256
112 max_output_size_bytes: int = 10 * 1024 * 1024 # 10 MB
113 max_files_open: int = 50
114 max_processes: int = 1
115 network_enabled: bool = False
116 disk_write_enabled: bool = False
118 # Execution constraints
119 timeout_seconds: float = 60.0
120 max_iterations: int = 10_000_000 # Safety net for infinite loops
122 # Security
123 block_dangerous_modules: bool = True
124 block_dangerous_builtins: bool = True
125 allowed_modules: set[str] = field(default_factory=set)
126 allowed_imports: set[str] = field(default_factory=set)
128 # Audit
129 enable_audit: bool = True
131 @classmethod
132 def for_level(cls, level: SecurityLevel) -> SandboxPolicy:
133 """Create a policy for a given security level."""
134 if level == SecurityLevel.RESTRICTED:
135 return cls(
136 max_cpu_time_seconds=5.0,
137 max_memory_mb=64,
138 max_output_size_bytes=1 * 1024 * 1024,
139 network_enabled=False,
140 disk_write_enabled=False,
141 timeout_seconds=10.0,
142 allowed_modules={
143 "math",
144 "json",
145 "datetime",
146 "collections",
147 "itertools",
148 "functools",
149 },
150 )
151 elif level == SecurityLevel.RELAXED:
152 return cls(
153 max_cpu_time_seconds=120.0,
154 max_memory_mb=1024,
155 max_output_size_bytes=100 * 1024 * 1024,
156 network_enabled=True,
157 disk_write_enabled=True,
158 timeout_seconds=300.0,
159 block_dangerous_modules=False,
160 )
161 else: # STANDARD
162 return cls()
165# ---------------------------------------------------------------------------
166# Sandbox Result
167# ---------------------------------------------------------------------------
170@dataclass(frozen=True)
171class SandboxResult:
172 """Immutable result of a sandboxed code execution."""
174 exit_code: int
175 stdout: str
176 stderr: str
177 execution_time_ms: float
178 peak_memory_mb: float
179 was_killed: bool = False
180 kill_reason: str = ""
181 error: str | None = None
182 timestamp: float = field(default_factory=time.time)
184 @property
185 def success(self) -> bool:
186 return self.exit_code == 0 and not self.was_killed
188 def to_dict(self) -> dict[str, Any]:
189 return {
190 "exit_code": self.exit_code,
191 "stdout": self.stdout[:1000],
192 "stderr": self.stderr[:1000],
193 "execution_time_ms": self.execution_time_ms,
194 "peak_memory_mb": self.peak_memory_mb,
195 "was_killed": self.was_killed,
196 "kill_reason": self.kill_reason,
197 "success": self.success,
198 }
201# ---------------------------------------------------------------------------
202# Audit Logger
203# ---------------------------------------------------------------------------
206class SandboxAuditLogger:
207 """Logs sandbox execution events for security auditing."""
209 def __init__(self):
210 self._events: list[dict[str, Any]] = []
212 def log(self, event_type: str, details: dict[str, Any]) -> None:
213 self._events.append(
214 {
215 "event": event_type,
216 "timestamp": time.time(),
217 **details,
218 }
219 )
221 def get_events(self, limit: int = 100) -> list[dict[str, Any]]:
222 return self._events[-limit:]
224 def clear(self) -> None:
225 self._events.clear()
228# ---------------------------------------------------------------------------
229# Sandbox Executor
230# ---------------------------------------------------------------------------
233class SandboxExecutor:
234 """
235 Execute Python code in an isolated sandbox with resource limits.
237 Uses subprocess isolation with resource limits set via RLIMIT.
238 """
240 def __init__(
241 self,
242 policy: SandboxPolicy | None = None,
243 audit: bool = True,
244 ):
245 self._policy = policy or SandboxPolicy()
246 self._auditor = SandboxAuditLogger() if audit else None
248 @property
249 def policy(self) -> SandboxPolicy:
250 return self._policy
252 def execute(self, code: str, globals_dict: dict | None = None) -> SandboxResult:
253 """
254 Execute code in sandbox.
256 Args:
257 code: Python code string to execute
258 globals_dict: Optional global namespace (restricted)
260 Returns:
261 SandboxResult with execution details
262 """
263 audit_id = f"sandbox_{int(time.time() * 1000)}"
265 if self._auditor:
266 self._auditor.log(
267 "execute",
268 {
269 "audit_id": audit_id,
270 "code_length": len(code),
271 "policy_level": self._policy.network_enabled and "relaxed" or "restricted",
272 },
273 )
275 start = time.time()
276 peak_memory = 0.0
278 try:
279 # Build restricted globals
280 self._build_restricted_globals(globals_dict or {})
282 # Write code to temp file for subprocess isolation
283 with tempfile.NamedTemporaryFile(
284 mode="w", suffix=".py", delete=False, prefix="sandbox_", dir=tempfile.gettempdir()
285 ) as f:
286 f.write(self._wrap_code_with_limits(code))
287 script_path = f.name
289 try:
290 result = subprocess.run(
291 [sys.executable, script_path],
292 capture_output=True,
293 text=True,
294 timeout=self._policy.timeout_seconds,
295 env=self._build_sandbox_env(),
296 preexec_fn=self._set_resource_limits if os.name != "nt" else None,
297 )
299 stdout = result.stdout[: self._policy.max_output_size_bytes]
300 stderr = result.stderr[: self._policy.max_output_size_bytes]
302 sandbox_result = SandboxResult(
303 exit_code=result.returncode,
304 stdout=stdout,
305 stderr=stderr,
306 execution_time_ms=(time.time() - start) * 1000,
307 peak_memory_mb=peak_memory,
308 )
310 except subprocess.TimeoutExpired:
311 sandbox_result = SandboxResult(
312 exit_code=-1,
313 stdout="",
314 stderr="",
315 execution_time_ms=(time.time() - start) * 1000,
316 peak_memory_mb=peak_memory,
317 was_killed=True,
318 kill_reason=f"Timeout: exceeded {self._policy.timeout_seconds}s",
319 error="Execution timed out",
320 )
321 finally:
322 try:
323 os.unlink(script_path)
324 except OSError:
325 pass
327 except Exception as e:
328 sandbox_result = SandboxResult(
329 exit_code=-1,
330 stdout="",
331 stderr=traceback.format_exc(),
332 execution_time_ms=(time.time() - start) * 1000,
333 peak_memory_mb=peak_memory,
334 error=str(e),
335 )
337 if self._auditor:
338 self._auditor.log(
339 "complete",
340 {
341 "audit_id": audit_id,
342 "success": sandbox_result.success,
343 "execution_time_ms": sandbox_result.execution_time_ms,
344 "exit_code": sandbox_result.exit_code,
345 },
346 )
348 return sandbox_result
350 def execute_sync(self, code: str, namespace: dict | None = None) -> SandboxResult:
351 """
352 Execute code synchronously in-process with restricted namespace.
354 Faster than execute() but slightly less isolated.
355 """
356 start = time.time()
357 audit_id = f"sync_{int(start * 1000)}"
359 if self._auditor:
360 self._auditor.log("execute_sync", {"audit_id": audit_id, "code_length": len(code)})
362 try:
363 restricted_globals = self._build_restricted_globals({})
365 exec(code, restricted_globals)
367 # Propagate results back to caller namespace
368 if namespace is not None:
369 namespace.update(
370 {
371 k: v
372 for k, v in restricted_globals.items()
373 if not k.startswith("__") and k not in self._policy.allowed_modules
374 }
375 )
377 result = SandboxResult(
378 exit_code=0,
379 stdout="",
380 stderr="",
381 execution_time_ms=(time.time() - start) * 1000,
382 peak_memory_mb=0.0,
383 )
384 except Exception as e:
385 result = SandboxResult(
386 exit_code=-1,
387 stdout="",
388 stderr=traceback.format_exc(),
389 execution_time_ms=(time.time() - start) * 1000,
390 peak_memory_mb=0.0,
391 error=str(e),
392 )
394 if self._auditor:
395 self._auditor.log(
396 "complete_sync",
397 {
398 "audit_id": audit_id,
399 "success": result.success,
400 },
401 )
403 return result
405 def _build_restricted_globals(self, extra: dict) -> dict:
406 """Build a restricted global namespace."""
407 safe_builtins = {
408 k: v
409 for k, v in __builtins__.items()
410 if k not in (self._policy.block_dangerous_builtins and DANGEROUS_BUILTINS or set())
411 }
413 globals_dict = {"__builtins__": safe_builtins}
415 # Add allowed modules
416 for mod_name in self._policy.allowed_modules:
417 try:
418 mod = __import__(mod_name)
419 globals_dict[mod_name] = mod
420 except ImportError:
421 pass
423 globals_dict.update(extra)
424 return globals_dict
426 def _build_sandbox_env(self) -> dict[str, str]:
427 """Build a restricted environment for subprocess."""
428 env = {
429 "PATH": "/usr/bin:/bin:/usr/local/bin",
430 "HOME": tempfile.gettempdir(),
431 "TMPDIR": tempfile.gettempdir(),
432 "PYTHONUNBUFFERED": "1",
433 "PYTHONDONTWRITEBYTECODE": "1",
434 "SANDBOX_MAX_CPU": str(self._policy.max_cpu_time_seconds),
435 "SANDBOX_MAX_MEMORY_MB": str(self._policy.max_memory_mb),
436 }
437 return env
439 def _set_resource_limits(self) -> None:
440 """Set OS-level resource limits (Unix only)."""
441 try:
442 # CPU time limit
443 cpu_seconds = int(self._policy.max_cpu_time_seconds)
444 resource.setrlimit(resource.RLIMIT_CPU, (cpu_seconds, cpu_seconds + 5))
446 # Memory limit
447 mem_bytes = self._policy.max_memory_mb * 1024 * 1024
448 resource.setrlimit(resource.RLIMIT_AS, (mem_bytes, mem_bytes))
450 # File descriptors
451 resource.setrlimit(
452 resource.RLIMIT_NOFILE,
453 (self._policy.max_files_open, self._policy.max_files_open),
454 )
456 # Processes
457 resource.setrlimit(
458 resource.RLIMIT_NPROC,
459 (self._policy.max_processes, self._policy.max_processes),
460 )
461 except (OSError, ValueError):
462 pass
464 def _wrap_code_with_limits(self, code: str) -> str:
465 """Wrap user code with safety limits."""
466 wrapper = f"""
467import sys
469# Blacklist dangerous modules via import hook
470_dangerous_modules = {repr(DANGEROUS_MODULES)}
472class _RestrictedFinder:
473 def find_spec(self, fullname, path, target=None):
474 if fullname in _dangerous_modules or fullname.startswith(tuple(m + '.' for m in _dangerous_modules)):
475 raise ImportError(f"Module '{{fullname}}' is restricted in sandbox")
476 return None
478sys.meta_path.insert(0, _RestrictedFinder())
480# Purge pre-cached dangerous modules from sys.modules
481for _m in list(sys.modules.keys()):
482 if _m in _dangerous_modules or any(_m.startswith(_d + '.') for _d in _dangerous_modules):
483 del sys.modules[_m]
485# Execute user code
486{code}
487"""
488 return wrapper
490 def get_audit_log(self) -> list[dict[str, Any]]:
491 if self._auditor:
492 return self._auditor.get_events()
493 return []
495 def clear_audit(self) -> None:
496 if self._auditor:
497 self._auditor.clear()
500# ---------------------------------------------------------------------------
501# Backward-compatible aliases (v1.x migration)
502# ---------------------------------------------------------------------------
504# RiskLevel = SecurityLevel (alias)
505RiskLevel = SecurityLevel
508@dataclass
509class SafetyReport:
510 """Safety analysis report for code/input evaluation."""
512 risk_level: RiskLevel = RiskLevel.STANDARD
513 is_safe: bool = True
514 findings: list[str] = field(default_factory=list)
515 recommendation: str = ""
516 score: float = 1.0
518 def to_dict(self) -> dict[str, Any]:
519 return {
520 "risk_level": self.risk_level.value,
521 "is_safe": self.is_safe,
522 "findings": self.findings,
523 "recommendation": self.recommendation,
524 "score": self.score,
525 }
528class LLMSafetyAnalyzer:
529 """LLM-based safety analyzer for code and content review."""
531 def __init__(self, policy: SandboxPolicy | None = None):
532 self._policy = policy or SandboxPolicy()
534 def analyze(self, code: str) -> SafetyReport:
535 findings: list[str] = []
536 is_safe = True
537 score = 1.0
539 for mod in DANGEROUS_MODULES:
540 if f"import {mod}" in code or f"from {mod}" in code:
541 findings.append(f"Uses dangerous module: {mod}")
542 is_safe = False
543 score = max(0.0, score - 0.15)
545 for builtin_name in DANGEROUS_BUILTINS:
546 if builtin_name in code:
547 findings.append(f"Uses dangerous builtin: {builtin_name}")
548 is_safe = False
549 score = max(0.0, score - 0.1)
551 if not is_safe:
552 return SafetyReport(
553 risk_level=RiskLevel.RESTRICTED,
554 is_safe=False,
555 findings=findings,
556 recommendation="Code contains potentially dangerous operations",
557 score=score,
558 )
559 return SafetyReport(
560 risk_level=RiskLevel.STANDARD,
561 is_safe=True,
562 findings=findings,
563 score=score,
564 )
567class Sandbox:
568 """Backward-compatible Sandbox wrapper around SandboxPolicy + SandboxExecutor."""
570 def __init__(self, policy: SandboxPolicy | None = None):
571 self._policy = policy or SandboxPolicy()
572 self._executor = SandboxExecutor(policy=self._policy)
574 @property
575 def policy(self) -> SandboxPolicy:
576 return self._policy
578 def run(self, code: str) -> SandboxResult:
579 return self._executor.execute(code)
581 def run_sync(self, code: str, namespace: dict | None = None) -> SandboxResult:
582 return self._executor.execute_sync(code, namespace)
585class SandboxManager:
586 """Backward-compatible SandboxManager — manages multiple sandbox instances."""
588 def __init__(self, default_policy: SandboxPolicy | None = None):
589 self._default_policy = default_policy or SandboxPolicy()
590 self._sandboxes: dict[str, Sandbox] = {}
592 def create(self, name: str, policy: SandboxPolicy | None = None) -> Sandbox:
593 sb = Sandbox(policy=policy or self._default_policy)
594 self._sandboxes[name] = sb
595 return sb
597 def get(self, name: str) -> Sandbox | None:
598 return self._sandboxes.get(name)
600 def remove(self, name: str) -> bool:
601 if name in self._sandboxes:
602 del self._sandboxes[name]
603 return True
604 return False
606 def list(self) -> builtins.list[str]:
607 return list(self._sandboxes.keys())
609 def execute_all(self, code: str) -> dict[str, SandboxResult]:
610 return {name: sb.run(code) for name, sb in self._sandboxes.items()}