Add root privilege check and warning display

- Add startup check in app.py for root/sudo privileges
- Show warning in terminal if not running as root
- Add running_as_root flag to TSCM devices API response
- Display privilege warning in TSCM UI when not running as root
- Show command to run with sudo in the warning
- Add CSS styling for privilege warning banner

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app.py

@@ -548,6 +548,28 @@ def main() -> None:
     print("=" * 50)
     print()
 
+    # Check if running as root (required for WiFi monitor mode, some BT operations)
+    import os
+    if os.geteuid() != 0:
+        print("\033[93m" + "=" * 50)
+        print("  ⚠️  WARNING: Not running as root/sudo")
+        print("=" * 50)
+        print("  Some features require root privileges:")
+        print("    - WiFi monitor mode and scanning")
+        print("    - Bluetooth low-level operations")
+        print("    - RTL-SDR access (on some systems)")
+        print()
+        print("  To run with full capabilities:")
+        print("    sudo -E venv/bin/python intercept.py")
+        print("=" * 50 + "\033[0m")
+        print()
+        # Store for API access
+        app.config['RUNNING_AS_ROOT'] = False
+    else:
+        app.config['RUNNING_AS_ROOT'] = True
+        print("Running as root - full capabilities enabled")
+        print()
+
     # Clean up any stale processes from previous runs
     cleanup_stale_processes()
 

routes/tscm.py

@@ -596,7 +596,25 @@ def get_tscm_devices():
     except Exception as e:
         logger.warning(f"Error detecting SDR devices: {e}")
 
-    return jsonify({'status': 'success', 'devices': devices})
+    # Check if running as root
+    import os
+    from flask import current_app
+    running_as_root = current_app.config.get('RUNNING_AS_ROOT', os.geteuid() == 0)
+
+    warnings = []
+    if not running_as_root:
+        warnings.append({
+            'type': 'privileges',
+            'message': 'Not running as root. WiFi monitor mode and some Bluetooth features require sudo.',
+            'action': 'Run with: sudo -E venv/bin/python intercept.py'
+        })
+
+    return jsonify({
+        'status': 'success',
+        'devices': devices,
+        'running_as_root': running_as_root,
+        'warnings': warnings
+    })
 
 
 def _scan_wifi_networks(interface: str) -> list[dict]:

templates/index.html

@@ -2075,6 +2075,31 @@
                     .tscm-status-message .status-icon {
                         font-size: 16px;
                     }
+                    .tscm-privilege-warning {
+                        padding: 10px 12px;
+                        background: rgba(255, 51, 51, 0.15);
+                        border: 1px solid rgba(255, 51, 51, 0.4);
+                        border-radius: 6px;
+                        color: var(--text-primary);
+                        font-size: 11px;
+                        display: flex;
+                        align-items: flex-start;
+                        gap: 10px;
+                        margin-bottom: 12px;
+                    }
+                    .tscm-privilege-warning .warning-icon {
+                        font-size: 18px;
+                        flex-shrink: 0;
+                    }
+                    .tscm-privilege-warning .warning-action {
+                        margin-top: 4px;
+                        font-family: 'JetBrains Mono', monospace;
+                        font-size: 10px;
+                        color: var(--accent-cyan);
+                        background: rgba(0, 0, 0, 0.3);
+                        padding: 4px 8px;
+                        border-radius: 3px;
+                    }
                     .tscm-device-reasons {
                         font-size: 10px;
                         color: var(--text-secondary);
@@ -10125,6 +10150,23 @@
                     sdrSelect.innerHTML = '<option value="">No SDR devices found</option>';
                 }
 
+                // Show warnings (e.g., not running as root)
+                const warningsDiv = document.getElementById('tscmDeviceWarnings');
+                if (data.warnings && data.warnings.length > 0) {
+                    warningsDiv.innerHTML = data.warnings.map(w =>
+                        `<div class="tscm-privilege-warning">
+                            <span class="warning-icon">⚠️</span>
+                            <div>
+                                <strong>${escapeHtml(w.message)}</strong>
+                                ${w.action ? `<div class="warning-action">${escapeHtml(w.action)}</div>` : ''}
+                            </div>
+                        </div>`
+                    ).join('');
+                    warningsDiv.style.display = 'block';
+                } else {
+                    warningsDiv.style.display = 'none';
+                }
+
             } catch (e) {
                 console.error('Failed to refresh TSCM devices:', e);
             }