hardening of script handling with configurable variables - making script execution more secure

apps/connect/handlers/script.py

@@ -1,28 +1,81 @@
 # connect/handlers/script.py
 import os
+import stat
 import subprocess
+from django.conf import settings
 from .base import IntegrationHandler
 
+
+def _is_path_allowed(real_path: str) -> bool:
+    # Ensure path is within one of the allowed directories
+    for base in getattr(settings, "CONNECT_ALLOWED_SCRIPT_DIRS", []):
+        base_abs = os.path.abspath(base) + os.sep
+        if real_path.startswith(base_abs):
+            return True
+    return False
+
+
 class ScriptHandler(IntegrationHandler):
     def execute(self):
-        script_path = self.integration.config.get("path")
+        raw_path = self.integration.config.get("path")
+        if not raw_path:
+            raise ValueError("Missing 'path' in integration config")
 
-        # Build environment variables from payload (prefixed for clarity)
-        env = os.environ.copy()
+        # Resolve and validate path
+        real_path = os.path.abspath(os.path.realpath(raw_path))
+
+        if not os.path.exists(real_path):
+            raise FileNotFoundError(f"Script not found: {real_path}")
+
+        if not _is_path_allowed(real_path):
+            raise PermissionError(
+                f"Script path '{real_path}' not within allowed directories: "
+                f"{getattr(settings, 'CONNECT_ALLOWED_SCRIPT_DIRS', [])}"
+            )
+
+        if getattr(settings, "CONNECT_SCRIPT_REQUIRE_EXECUTABLE", True):
+            if not os.access(real_path, os.X_OK):
+                raise PermissionError(f"Script is not executable: {real_path}")
+
+        if getattr(settings, "CONNECT_SCRIPT_DISALLOW_WORLD_WRITABLE", True):
+            st = os.stat(real_path)
+            if st.st_mode & stat.S_IWOTH:
+                raise PermissionError(
+                    f"Refusing to execute world-writable script: {real_path}"
+                )
+
+        # Build a sanitized minimal environment; avoid inheriting secrets
+        env = {
+            "PATH": "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
+        }
         for key, value in (self.payload or {}).items():
-            # Convert keys to upper snake case and prefix
             env_key = f"DISPATCHARR_{str(key).upper()}"
-            env[env_key] = str(value) if value is not None else ""
+            env[env_key] = "" if value is None else str(value)
+
+        # Run with a timeout to prevent hanging scripts
+        timeout = getattr(settings, "CONNECT_SCRIPT_TIMEOUT", 10)
+        max_out = getattr(settings, "CONNECT_SCRIPT_MAX_OUTPUT", 65536)
 
         result = subprocess.run(
-            [script_path],
+            [real_path],
             capture_output=True,
             text=True,
             env=env,
+            timeout=timeout,
+            cwd=os.path.dirname(real_path) or None,
         )
+
+        # Truncate outputs to avoid excessive memory/logging
+        stdout = result.stdout or ""
+        stderr = result.stderr or ""
+        if len(stdout) > max_out:
+            stdout = stdout[:max_out] + "... [truncated]"
+        if len(stderr) > max_out:
+            stderr = stderr[:max_out] + "... [truncated]"
+
         return {
             "exit_code": result.returncode,
-            "stdout": result.stdout,
-            "stderr": result.stderr,
+            "stdout": stdout,
+            "stderr": stderr,
             "success": result.returncode == 0,
         }

dispatcharr/settings.py

@@ -412,3 +412,18 @@ LOGGING = {
         "level": LOG_LEVEL,  # Use user-configured level instead of hardcoded 'INFO'
     },
 }
+
+# Connect script execution safety settings
+# Allowed base directories for custom scripts; real paths must be inside
+_allowed_dirs_env = os.environ.get("DISPATCHARR_ALLOWED_SCRIPT_DIRS", "/data/plugins")
+CONNECT_ALLOWED_SCRIPT_DIRS = [p for p in _allowed_dirs_env.split(":") if p]
+
+# Max execution time (seconds) for scripts
+CONNECT_SCRIPT_TIMEOUT = int(os.environ.get("DISPATCHARR_SCRIPT_TIMEOUT", "10"))
+
+# Truncate stdout/stderr to this many characters to avoid large outputs
+CONNECT_SCRIPT_MAX_OUTPUT = int(os.environ.get("DISPATCHARR_SCRIPT_MAX_OUTPUT", "65536"))
+
+# Require executable bit and disallow world-writable files
+CONNECT_SCRIPT_REQUIRE_EXECUTABLE = True
+CONNECT_SCRIPT_DISALLOW_WORLD_WRITABLE = True