Adds security tools, such as a rate limiter, IP block/allow, server logs (#1606)

* added ratelimiter
* Adds server logs to admin ui
* Added IP allow/ban list
* fixed remove ips
* Split rate limit number and unit
* security tab and background tasks for killswitch
* fix test for auditor api

---------

Co-authored-by: dni ⚡ <office@dnilabs.com>

lnbits/core/tasks.py

@@ -1,20 +1,102 @@
 import asyncio
-from typing import Dict
+from typing import Dict, Optional
 
 import httpx
 from loguru import logger
 
+from lnbits.settings import get_wallet_class, settings
 from lnbits.tasks import SseListenersDict, register_invoice_listener
 
 from . import db
 from .crud import get_balance_notify, get_wallet
 from .models import Payment
-from .services import websocketUpdater
+from .services import get_balance_delta, switch_to_voidwallet, websocketUpdater
 
 api_invoice_listeners: Dict[str, asyncio.Queue] = SseListenersDict(
     "api_invoice_listeners"
 )
 
+killswitch: Optional[asyncio.Task] = None
+watchdog: Optional[asyncio.Task] = None
+
+
+async def register_killswitch():
+    """
+    Registers a killswitch which will check lnbits-status repository
+    for a signal from LNbits and will switch to VoidWallet if the killswitch is triggered.
+    """
+    logger.debug("Starting killswitch task")
+    global killswitch
+    killswitch = asyncio.create_task(killswitch_task())
+
+
+async def unregister_killswitch():
+    """
+    Unregisters a killswitch taskl
+    """
+    global killswitch
+    if killswitch:
+        logger.debug("Stopping killswitch task")
+        killswitch.cancel()
+
+
+async def killswitch_task():
+    while True:
+        WALLET = get_wallet_class()
+        if settings.lnbits_killswitch and WALLET.__class__.__name__ != "VoidWallet":
+            with httpx.Client() as client:
+                try:
+                    r = client.get(settings.lnbits_status_manifest, timeout=4)
+                    r.raise_for_status()
+                    if r.status_code == 200:
+                        ks = r.json().get("killswitch")
+                        if ks and ks == 1:
+                            logger.error(
+                                "Switching to VoidWallet. Killswitch triggered."
+                            )
+                            await switch_to_voidwallet()
+                except (httpx.ConnectError, httpx.RequestError):
+                    logger.error(
+                        f"Cannot fetch lnbits status manifest. {settings.lnbits_status_manifest}"
+                    )
+        await asyncio.sleep(settings.lnbits_killswitch_interval * 60)
+
+
+async def register_watchdog():
+    """
+    Registers a watchdog which will check lnbits balance and nodebalance
+    and will switch to VoidWallet if the watchdog delta is reached.
+    """
+    # TODO: implement watchdog porperly
+    # logger.debug("Starting watchdog task")
+    # global watchdog
+    # watchdog = asyncio.create_task(watchdog_task())
+
+
+async def unregister_watchdog():
+    """
+    Unregisters a watchdog task
+    """
+    global watchdog
+    if watchdog:
+        logger.debug("Stopping watchdog task")
+        watchdog.cancel()
+
+
+async def watchdog_task():
+    while True:
+        WALLET = get_wallet_class()
+        if settings.lnbits_watchdog and WALLET.__class__.__name__ != "VoidWallet":
+            try:
+                delta, *_ = await get_balance_delta()
+                logger.debug(f"Running watchdog task. current delta: {delta}")
+                if delta + settings.lnbits_watchdog_delta <= 0:
+                    logger.error(f"Switching to VoidWallet. current delta: {delta}")
+                    await switch_to_voidwallet()
+            except Exception as e:
+                logger.error("Error in watchdog task", e)
+        await asyncio.sleep(settings.lnbits_watchdog_interval * 60)
+
 
 async def register_task_listeners():
     """