Files
meshcore-bot/modules/security_utils.py
agessaman afda22f0fe Refactor database path and placeholder handling across modules
- Replaced the validate_safe_path function with a new resolve_path utility to simplify database path resolution in BotDataViewer, BotIntegration, and MapUploaderService.
- Updated the logic to ensure that both relative and absolute paths are handled correctly, enhancing the robustness of database connections.
- Improved code readability and maintainability by centralizing path resolution logic.
- Centralized placeholder handling in utils instead of individual function handlers
2025-12-29 15:42:35 -08:00

358 lines
11 KiB
Python

#!/usr/bin/env python3
"""
Security Utilities for MeshCore Bot
Provides centralized security validation functions to prevent common attacks
"""
import re
import ipaddress
import socket
import platform
import os
from pathlib import Path
from typing import Optional
from urllib.parse import urlparse
import logging
logger = logging.getLogger('MeshCoreBot.Security')
def _is_nix_environment() -> bool:
"""
Detect if running in a Nix environment
Returns:
True if running in Nix build or NixOS
"""
# Check for Nix store path (most reliable indicator)
if 'NIX_STORE' in os.environ:
return True
# Check if we're in a Nix store path
try:
current_path = Path.cwd().resolve()
# Nix store paths typically look like /nix/store/<hash>-<name>
if '/nix/store/' in str(current_path):
return True
except Exception:
pass
# Check for Nix-related environment variables
nix_env_vars = ['NIX_PATH', 'NIX_REMOTE', 'IN_NIX_SHELL']
if any(var in os.environ for var in nix_env_vars):
return True
return False
def validate_external_url(url: str, allow_localhost: bool = False, timeout: float = 2.0) -> bool:
"""
Validate that URL points to safe external resource (SSRF protection)
Args:
url: URL to validate
allow_localhost: Whether to allow localhost/private IPs (default: False)
timeout: DNS resolution timeout in seconds (default: 2.0)
Returns:
True if URL is safe, False otherwise
Raises:
ValueError: If URL is invalid or unsafe
"""
try:
parsed = urlparse(url)
# Only allow HTTP/HTTPS
if parsed.scheme not in ['http', 'https']:
logger.warning(f"URL scheme not allowed: {parsed.scheme}")
return False
# Reject file:// and other dangerous schemes
if not parsed.netloc:
logger.warning(f"URL missing network location: {url}")
return False
# Resolve and check if IP is internal/private (with timeout)
try:
# Set socket timeout for DNS resolution
# Note: getdefaulttimeout() can return None (no timeout), which is valid
old_timeout = socket.getdefaulttimeout()
socket.setdefaulttimeout(timeout)
try:
ip = socket.gethostbyname(parsed.hostname)
finally:
# Restore original timeout (None means no timeout, which is correct)
socket.setdefaulttimeout(old_timeout)
ip_obj = ipaddress.ip_address(ip)
# If localhost is not allowed, reject private/internal IPs
if not allow_localhost:
# Reject private/internal IPs
if ip_obj.is_private or ip_obj.is_loopback or ip_obj.is_link_local:
logger.warning(f"URL resolves to private/internal IP: {ip}")
return False
# Reject reserved ranges
if ip_obj.is_reserved or ip_obj.is_multicast:
logger.warning(f"URL resolves to reserved/multicast IP: {ip}")
return False
except socket.gaierror as e:
logger.warning(f"Failed to resolve hostname {parsed.hostname}: {e}")
return False
except socket.timeout:
logger.warning(f"DNS resolution timeout for {parsed.hostname}")
return False
return True
except Exception as e:
logger.error(f"URL validation failed: {e}")
return False
def validate_safe_path(file_path: str, base_dir: str = '.', allow_absolute: bool = False) -> Path:
"""
Validate that path is safe with configurable restrictions
When allow_absolute=False (default):
- Paths must be within base_dir (prevents path traversal)
- Blocks dangerous system directories
When allow_absolute=True:
- Allows paths outside base_dir (for user-configured database/log locations)
- Still blocks dangerous system directories
- In Nix environments, dangerous directory checks are relaxed (Nix provides isolation)
Args:
file_path: Path to validate
base_dir: Base directory that path must be within (when allow_absolute=False)
allow_absolute: Whether to allow absolute paths outside base_dir
Returns:
Resolved Path object if safe
Raises:
ValueError: If path is unsafe or attempts traversal
"""
try:
# Resolve base directory to absolute path
base = Path(base_dir).resolve()
# Resolve target path relative to base_dir (not current working directory)
# If file_path is absolute, use it directly; otherwise join with base_dir
if Path(file_path).is_absolute():
target = Path(file_path).resolve()
else:
# Join with base_dir first, then resolve to handle relative paths correctly
target = (base / file_path).resolve()
# If absolute paths are not allowed, ensure target is within base
if not allow_absolute:
# Check if target is within base directory
try:
target.relative_to(base)
except ValueError:
raise ValueError(
f"Path traversal detected: {file_path} is not within {base_dir}"
)
# Check for dangerous system paths (OS-specific)
# In Nix environments, skip this check as Nix provides strong isolation
is_nix = _is_nix_environment()
if not is_nix:
system = platform.system()
if system == 'Windows':
dangerous_prefixes = [
'C:\\Windows\\System32',
'C:\\Windows\\SysWOW64',
'C:\\Program Files',
'C:\\ProgramData',
'C:\\Windows\\System',
]
# Check against both forward and backslash paths
target_str = str(target).lower()
dangerous = any(target_str.startswith(prefix.lower()) for prefix in dangerous_prefixes)
elif system == 'Darwin': # macOS
dangerous_prefixes = [
'/System',
'/Library',
'/private',
'/usr/bin',
'/usr/sbin',
'/sbin',
'/bin',
]
target_str = str(target)
dangerous = any(target_str.startswith(prefix) for prefix in dangerous_prefixes)
else: # Linux and other Unix-like systems
dangerous_prefixes = ['/etc', '/sys', '/proc', '/dev', '/bin', '/sbin', '/boot']
target_str = str(target)
dangerous = any(target_str.startswith(prefix) for prefix in dangerous_prefixes)
if dangerous:
raise ValueError(f"Access to system directory denied: {file_path}")
return target
except ValueError:
# Re-raise ValueError as-is (these are our validation errors)
raise
except Exception as e:
raise ValueError(f"Invalid or unsafe file path: {file_path} - {e}")
def sanitize_input(content: str, max_length: Optional[int] = 500, strip_controls: bool = True) -> str:
"""
Sanitize user input to prevent injection attacks
Args:
content: Input string to sanitize
max_length: Maximum allowed length (default: 500 chars, None to disable length check)
strip_controls: Whether to remove control characters (default: True)
Returns:
Sanitized string
Raises:
ValueError: If max_length is negative
"""
if not isinstance(content, str):
content = str(content)
# Validate max_length if provided
if max_length is not None:
if max_length < 0:
raise ValueError(f"max_length must be non-negative, got {max_length}")
# Limit length to prevent DoS
if len(content) > max_length:
content = content[:max_length]
logger.debug(f"Input truncated to {max_length} characters")
# Remove control characters except newline, carriage return, tab
if strip_controls:
# Keep only printable characters plus common whitespace
content = ''.join(
char for char in content
if ord(char) >= 32 or char in '\n\r\t'
)
# Remove null bytes (can cause issues in C libraries)
content = content.replace('\x00', '')
return content.strip()
def validate_api_key_format(api_key: str, min_length: int = 16) -> bool:
"""
Validate API key format
Args:
api_key: API key to validate
min_length: Minimum required length (default: 16)
Returns:
True if format is valid, False otherwise
"""
if not isinstance(api_key, str):
return False
# Check minimum length
if len(api_key) < min_length:
return False
# Check for obviously invalid patterns
invalid_patterns = [
'your_api_key_here',
'placeholder',
'example',
'test_key',
'12345',
'aaaa',
]
api_key_lower = api_key.lower()
if any(pattern in api_key_lower for pattern in invalid_patterns):
return False
# Check that it's not all the same character
if len(set(api_key)) < 3:
return False
return True
def validate_pubkey_format(pubkey: str, expected_length: int = 64) -> bool:
"""
Validate public key format (hex string)
Args:
pubkey: Public key to validate
expected_length: Expected length in characters (default: 64 for ed25519)
Returns:
True if format is valid, False otherwise
"""
if not isinstance(pubkey, str):
return False
# Check exact length
if len(pubkey) != expected_length:
return False
# Check hex format
if not re.match(r'^[0-9a-fA-F]+$', pubkey):
return False
return True
def validate_port_number(port: int, allow_privileged: bool = False) -> bool:
"""
Validate port number
Args:
port: Port number to validate
allow_privileged: Whether to allow privileged ports <1024 (default: False)
Returns:
True if port is valid, False otherwise
"""
if not isinstance(port, int):
return False
min_port = 1 if allow_privileged else 1024
max_port = 65535
return min_port <= port <= max_port
def validate_integer_range(value: int, min_value: int, max_value: int, name: str = "value") -> bool:
"""
Validate integer is within range
Args:
value: Integer to validate
min_value: Minimum allowed value (inclusive)
max_value: Maximum allowed value (inclusive)
name: Name of the value for error messages
Returns:
True if valid
Raises:
ValueError: If value is out of range
"""
if not isinstance(value, int):
raise ValueError(f"{name} must be an integer, got {type(value).__name__}")
if value < min_value or value > max_value:
raise ValueError(
f"{name} must be between {min_value} and {max_value}, got {value}"
)
return True