Merge pull request #5585 from mailcow/feat/nftables

[Netfilter] add nftables support

data/Dockerfiles/netfilter/Dockerfile

@@ -1,6 +1,8 @@
 FROM alpine:3.17
 LABEL maintainer "The Infrastructure Company GmbH <info@servercow.de>"
 
+WORKDIR /app
+
 ENV XTABLES_LIBDIR /usr/lib/xtables
 ENV PYTHON_IPTABLES_XTABLES_VERSION 12
 ENV IPTABLES_LIBDIR /usr/lib
@@ -14,10 +16,13 @@ RUN apk add --virtual .build-deps \
   iptables \
   ip6tables \
   xtables-addons \
+  nftables \
   tzdata \
   py3-pip \
+  py3-nftables \
   musl-dev \
 && pip3 install --ignore-installed --upgrade pip \
+  jsonschema \
   python-iptables \
   redis \
   ipaddress \
@@ -26,5 +31,10 @@ RUN apk add --virtual .build-deps \
 
 #  && pip3 install --upgrade pip python-iptables==0.13.0 redis ipaddress dnspython \
 
-COPY server.py /
+COPY modules /app/modules
-CMD ["python3", "-u", "/server.py"]
+COPY main.py /app/
+COPY ./docker-entrypoint.sh /app/
+
+RUN chmod +x /app/docker-entrypoint.sh
+
+CMD ["/bin/sh", "-c", "/app/docker-entrypoint.sh"]

data/Dockerfiles/netfilter/docker-entrypoint.sh

@@ -0,0 +1,29 @@
+#!/bin/sh
+
+backend=iptables
+
+nft list table ip filter &>/dev/null
+nftables_found=$?
+
+iptables -L -n &>/dev/null
+iptables_found=$?
+
+if [ $nftables_found -lt $iptables_found ]; then
+  backend=nftables
+fi
+
+if [ $nftables_found -gt $iptables_found ]; then
+  backend=iptables
+fi
+
+if [ $nftables_found -eq 0 ] && [ $nftables_found -eq $iptables_found ]; then
+  nftables_lines=$(nft list ruleset | wc -l)
+  iptables_lines=$(iptables-save | wc -l)
+  if [ $nftables_lines -gt $iptables_lines ]; then
+    backend=nftables
+  else
+    backend=iptables
+  fi
+fi
+
+exec python -u /app/main.py $backend

data/Dockerfiles/netfilter/main.py

@@ -13,10 +13,14 @@ from threading import Thread
 from threading import Lock
 import redis
 import json
-import iptc
 import dns.resolver
 import dns.exception
+from modules.Logger import Logger
+from modules.IPTables import IPTables
+from modules.NFTables import NFTables
 
+
+# connect to redis
 while True:
   try:
     redis_slaveof_ip = os.getenv('REDIS_SLAVEOF_IP', '')
@@ -31,34 +35,33 @@ while True:
     time.sleep(3)
   else:
     break
-
 pubsub = r.pubsub()
 
+# rename fail2ban to netfilter
+if r.exists('F2B_LOG'):
+  r.rename('F2B_LOG', 'NETFILTER_LOG')
+
+
+# globals
 WHITELIST = []
 BLACKLIST= []
-
 bans = {}
-
 quit_now = False
 exit_code = 0
 lock = Lock()
 
-def log(priority, message):
-  tolog = {}
-  tolog['time'] = int(round(time.time()))
-  tolog['priority'] = priority
-  tolog['message'] = message
-  r.lpush('NETFILTER_LOG', json.dumps(tolog, ensure_ascii=False))
-  print(message)
 
-def logWarn(message):
+# init Logger
-  log('warn', message)
+logger = Logger(r)
+# init backend
+backend = sys.argv[1]
+if backend == "nftables":
+  logger.logInfo('Using NFTables backend')
+  tables = NFTables("MAILCOW", logger)
+else:
+  logger.logInfo('Using IPTables backend')
+  tables = IPTables("MAILCOW", logger)
 
-def logCrit(message):
-  log('crit', message)
-
-def logInfo(message):
-  log('info', message)
 
 def refreshF2boptions():
   global f2boptions
@@ -79,7 +82,7 @@ def refreshF2boptions():
     try:
       f2boptions = json.loads(r.get('F2B_OPTIONS'))
     except ValueError:
-      print('Error loading F2B options: F2B_OPTIONS is not json')
+      logger.logCrit('Error loading F2B options: F2B_OPTIONS is not json')
       quit_now = True
       exit_code = 2
 
@@ -120,43 +123,22 @@ def refreshF2bregex():
       f2bregex = {}
       f2bregex = json.loads(r.get('F2B_REGEX'))
     except ValueError:
-      print('Error loading F2B options: F2B_REGEX is not json')
+      logger.logCrit('Error loading F2B options: F2B_REGEX is not json')
       quit_now = True
       exit_code = 2
 
-if r.exists('F2B_LOG'):
+def get_ip(address):
-  r.rename('F2B_LOG', 'NETFILTER_LOG')
+  ip = ipaddress.ip_address(address)
+  if type(ip) is ipaddress.IPv6Address and ip.ipv4_mapped:
+    ip = ip.ipv4_mapped
+  if ip.is_private or ip.is_loopback:
+    return False
   
-def mailcowChainOrder():
+  return ip
-  global lock
-  global quit_now
-  global exit_code
-  while not quit_now:
-    time.sleep(10)
-    with lock:
-      filter4_table = iptc.Table(iptc.Table.FILTER)
-      filter6_table = iptc.Table6(iptc.Table6.FILTER)
-      filter4_table.refresh()
-      filter6_table.refresh()
-      for f in [filter4_table, filter6_table]:
-        forward_chain = iptc.Chain(f, 'FORWARD')
-        input_chain = iptc.Chain(f, 'INPUT')
-        for chain in [forward_chain, input_chain]:
-          target_found = False
-          for position, item in enumerate(chain.rules):
-            if item.target.name == 'MAILCOW':
-              target_found = True
-              if position > 2:
-                logCrit('Error in %s chain order: MAILCOW on position %d, restarting container' % (chain.name, position))
-                quit_now = True
-                exit_code = 2
-          if not target_found:
-            logCrit('Error in %s chain: MAILCOW target not found, restarting container' % (chain.name))
-            quit_now = True
-            exit_code = 2
 
 def ban(address):
   global lock
+
   refreshF2boptions()
   BAN_TIME = int(f2boptions['ban_time'])
   BAN_TIME_INCREMENT = bool(f2boptions['ban_time_increment'])
@@ -165,23 +147,18 @@ def ban(address):
   NETBAN_IPV4 = '/' + str(f2boptions['netban_ipv4'])
   NETBAN_IPV6 = '/' + str(f2boptions['netban_ipv6'])
 
-  ip = ipaddress.ip_address(address)
+  ip = get_ip(address)
-  if type(ip) is ipaddress.IPv6Address and ip.ipv4_mapped:
+  if not ip: return
-    ip = ip.ipv4_mapped
+  address = str(ip)
-    address = str(ip)
-  if ip.is_private or ip.is_loopback:
-    return
-
   self_network = ipaddress.ip_network(address)
 
   with lock:
     temp_whitelist = set(WHITELIST)
-
   if temp_whitelist:
     for wl_key in temp_whitelist:
       wl_net = ipaddress.ip_network(wl_key, False)
       if wl_net.overlaps(self_network):
-        logInfo('Address %s is whitelisted by rule %s' % (self_network, wl_net))
+        logger.logInfo('Address %s is whitelisted by rule %s' % (self_network, wl_net))
         return
 
   net = ipaddress.ip_network((address + (NETBAN_IPV4 if type(ip) is ipaddress.IPv4Address else NETBAN_IPV6)), strict=False)
@@ -190,60 +167,44 @@ def ban(address):
   if not net in bans:
     bans[net] = {'attempts': 0, 'last_attempt': 0, 'ban_counter': 0}
 
+  current_attempt = time.time()
+  if current_attempt - bans[net]['last_attempt'] > RETRY_WINDOW:
+    bans[net]['attempts'] = 0
+
   bans[net]['attempts'] += 1
-  bans[net]['last_attempt'] = time.time()
+  bans[net]['last_attempt'] = current_attempt
 
   if bans[net]['attempts'] >= MAX_ATTEMPTS:
     cur_time = int(round(time.time()))
     NET_BAN_TIME = BAN_TIME if not BAN_TIME_INCREMENT else BAN_TIME * 2 ** bans[net]['ban_counter']
-    logCrit('Banning %s for %d minutes' % (net, NET_BAN_TIME / 60 ))
+    logger.logCrit('Banning %s for %d minutes' % (net, NET_BAN_TIME / 60 ))
     if type(ip) is ipaddress.IPv4Address:
       with lock:
-        chain = iptc.Chain(iptc.Table(iptc.Table.FILTER), 'MAILCOW')
+        tables.banIPv4(net)
-        rule = iptc.Rule()
-        rule.src = net
-        target = iptc.Target(rule, "REJECT")
-        rule.target = target
-        if rule not in chain.rules:
-          chain.insert_rule(rule)
     else:
       with lock:
-        chain = iptc.Chain(iptc.Table6(iptc.Table6.FILTER), 'MAILCOW')
+        tables.banIPv6(net)
-        rule = iptc.Rule6()
+
-        rule.src = net
-        target = iptc.Target(rule, "REJECT")
-        rule.target = target
-        if rule not in chain.rules:
-          chain.insert_rule(rule)
     r.hset('F2B_ACTIVE_BANS', '%s' % net, cur_time + NET_BAN_TIME)
   else:
-    logWarn('%d more attempts in the next %d seconds until %s is banned' % (MAX_ATTEMPTS - bans[net]['attempts'], RETRY_WINDOW, net))
+    logger.logWarn('%d more attempts in the next %d seconds until %s is banned' % (MAX_ATTEMPTS - bans[net]['attempts'], RETRY_WINDOW, net))
 
 def unban(net):
   global lock
+
   if not net in bans:
-   logInfo('%s is not banned, skipping unban and deleting from queue (if any)' % net)
+   logger.logInfo('%s is not banned, skipping unban and deleting from queue (if any)' % net)
    r.hdel('F2B_QUEUE_UNBAN', '%s' % net)
    return
-  logInfo('Unbanning %s' % net)
+
+  logger.logInfo('Unbanning %s' % net)
   if type(ipaddress.ip_network(net)) is ipaddress.IPv4Network:
     with lock:
-      chain = iptc.Chain(iptc.Table(iptc.Table.FILTER), 'MAILCOW')
+      tables.unbanIPv4(net)
-      rule = iptc.Rule()
-      rule.src = net
-      target = iptc.Target(rule, "REJECT")
-      rule.target = target
-      if rule in chain.rules:
-        chain.delete_rule(rule)
   else:
     with lock:
-      chain = iptc.Chain(iptc.Table6(iptc.Table6.FILTER), 'MAILCOW')
+      tables.unbanIPv6(net)
-      rule = iptc.Rule6()
+
-      rule.src = net
-      target = iptc.Target(rule, "REJECT")
-      rule.target = target
-      if rule in chain.rules:
-        chain.delete_rule(rule)
   r.hdel('F2B_ACTIVE_BANS', '%s' % net)
   r.hdel('F2B_QUEUE_UNBAN', '%s' % net)
   if net in bans:
@@ -252,73 +213,44 @@ def unban(net):
 
 def permBan(net, unban=False):
   global lock
+
+  is_unbanned = False
+  is_banned = False
   if type(ipaddress.ip_network(net, strict=False)) is ipaddress.IPv4Network:
     with lock:
-      chain = iptc.Chain(iptc.Table(iptc.Table.FILTER), 'MAILCOW')
+      if unban:
-      rule = iptc.Rule()
+        is_unbanned = tables.unbanIPv4(net)
-      rule.src = net
+      else:
-      target = iptc.Target(rule, "REJECT")
+        is_banned = tables.banIPv4(net)
-      rule.target = target
-      if rule not in chain.rules and not unban:
-        logCrit('Add host/network %s to blacklist' % net)
-        chain.insert_rule(rule)
-        r.hset('F2B_PERM_BANS', '%s' % net, int(round(time.time())))
-      elif rule in chain.rules and unban:
-        logCrit('Remove host/network %s from blacklist' % net)
-        chain.delete_rule(rule)
-        r.hdel('F2B_PERM_BANS', '%s' % net)
   else:
     with lock:
-      chain = iptc.Chain(iptc.Table6(iptc.Table6.FILTER), 'MAILCOW')
+      if unban:
-      rule = iptc.Rule6()
+        is_unbanned = tables.unbanIPv6(net)
-      rule.src = net
+      else:
-      target = iptc.Target(rule, "REJECT")
+        is_banned = tables.banIPv6(net)
-      rule.target = target
-      if rule not in chain.rules and not unban:
-        logCrit('Add host/network %s to blacklist' % net)
-        chain.insert_rule(rule)
-        r.hset('F2B_PERM_BANS', '%s' % net, int(round(time.time())))
-      elif rule in chain.rules and unban:
-        logCrit('Remove host/network %s from blacklist' % net)
-        chain.delete_rule(rule)
-        r.hdel('F2B_PERM_BANS', '%s' % net)
 
-def quit(signum, frame):
+
-  global quit_now
+  if is_unbanned:
-  quit_now = True
+    r.hdel('F2B_PERM_BANS', '%s' % net)
+    logger.logCrit('Removed host/network %s from blacklist' % net)
+  elif is_banned:
+    r.hset('F2B_PERM_BANS', '%s' % net, int(round(time.time())))
+    logger.logCrit('Added host/network %s to blacklist' % net)
 
 def clear():
   global lock
-  logInfo('Clearing all bans')
+  logger.logInfo('Clearing all bans')
   for net in bans.copy():
     unban(net)
   with lock:
-    filter4_table = iptc.Table(iptc.Table.FILTER)
+    tables.clearIPv4Table()
-    filter6_table = iptc.Table6(iptc.Table6.FILTER)
+    tables.clearIPv6Table()
-    for filter_table in [filter4_table, filter6_table]:
-      filter_table.autocommit = False
-      forward_chain = iptc.Chain(filter_table, "FORWARD")
-      input_chain = iptc.Chain(filter_table, "INPUT")
-      mailcow_chain = iptc.Chain(filter_table, "MAILCOW")
-      if mailcow_chain in filter_table.chains:
-        for rule in mailcow_chain.rules:
-          mailcow_chain.delete_rule(rule)
-        for rule in forward_chain.rules:
-          if rule.target.name == 'MAILCOW':
-            forward_chain.delete_rule(rule)
-        for rule in input_chain.rules:
-          if rule.target.name == 'MAILCOW':
-            input_chain.delete_rule(rule)
-        filter_table.delete_chain("MAILCOW")
-      filter_table.commit()
-      filter_table.refresh()
-      filter_table.autocommit = True
     r.delete('F2B_ACTIVE_BANS')
     r.delete('F2B_PERM_BANS')
     pubsub.unsubscribe()
 
 def watch():
-  logInfo('Watching Redis channel F2B_CHANNEL')
+  logger.logInfo('Watching Redis channel F2B_CHANNEL')
   pubsub.subscribe('F2B_CHANNEL')
 
   global quit_now
@@ -339,10 +271,10 @@ def watch():
               ip = ipaddress.ip_address(addr)
               if ip.is_private or ip.is_loopback:
                 continue
-              logWarn('%s matched rule id %s (%s)' % (addr, rule_id, item['data']))
+              logger.logWarn('%s matched rule id %s (%s)' % (addr, rule_id, item['data']))
               ban(addr)
     except Exception as ex:
-      logWarn('Error reading log line from pubsub: %s' % ex)
+      logger.logWarn('Error reading log line from pubsub: %s' % ex)
       quit_now = True
       exit_code = 2
 
@@ -350,87 +282,19 @@ def snat4(snat_target):
   global lock
   global quit_now
 
-  def get_snat4_rule():
-    rule = iptc.Rule()
-    rule.src = os.getenv('IPV4_NETWORK', '172.22.1') + '.0/24'
-    rule.dst = '!' + rule.src
-    target = rule.create_target("SNAT")
-    target.to_source = snat_target
-    match = rule.create_match("comment")
-    match.comment = f'{int(round(time.time()))}'
-    return rule
-
   while not quit_now:
     time.sleep(10)
     with lock:
-      try:
+      tables.snat4(snat_target, os.getenv('IPV4_NETWORK', '172.22.1') + '.0/24')
-        table = iptc.Table('nat')
-        table.refresh()
-        chain = iptc.Chain(table, 'POSTROUTING')
-        table.autocommit = False
-        new_rule = get_snat4_rule()
-
-        if not chain.rules:
-          # if there are no rules in the chain, insert the new rule directly
-          logInfo(f'Added POSTROUTING rule for source network {new_rule.src} to SNAT target {snat_target}')
-          chain.insert_rule(new_rule)
-        else:
-          for position, rule in enumerate(chain.rules):
-            if not hasattr(rule.target, 'parameter'):
-                continue
-            match = all((
-              new_rule.get_src() == rule.get_src(),
-              new_rule.get_dst() == rule.get_dst(),
-              new_rule.target.parameters == rule.target.parameters,
-              new_rule.target.name == rule.target.name
-            ))
-            if position == 0:
-              if not match:
-                logInfo(f'Added POSTROUTING rule for source network {new_rule.src} to SNAT target {snat_target}')
-                chain.insert_rule(new_rule)
-            else:
-              if match:
-                logInfo(f'Remove rule for source network {new_rule.src} to SNAT target {snat_target} from POSTROUTING chain at position {position}')
-                chain.delete_rule(rule)
-
-        table.commit()
-        table.autocommit = True
-      except:
-        print('Error running SNAT4, retrying...')
 
 def snat6(snat_target):
   global lock
   global quit_now
 
-  def get_snat6_rule():
-    rule = iptc.Rule6()
-    rule.src = os.getenv('IPV6_NETWORK', 'fd4d:6169:6c63:6f77::/64')
-    rule.dst = '!' + rule.src
-    target = rule.create_target("SNAT")
-    target.to_source = snat_target
-    return rule
-
   while not quit_now:
     time.sleep(10)
     with lock:
-      try:
+      tables.snat6(snat_target, os.getenv('IPV6_NETWORK', 'fd4d:6169:6c63:6f77::/64'))
-        table = iptc.Table6('nat')
-        table.refresh()
-        chain = iptc.Chain(table, 'POSTROUTING')
-        table.autocommit = False
-        if get_snat6_rule() not in chain.rules:
-          logInfo('Added POSTROUTING rule for source network %s to SNAT target %s' % (get_snat6_rule().src, snat_target))
-          chain.insert_rule(get_snat6_rule())
-          table.commit()
-        else:
-          for position, item in enumerate(chain.rules):
-            if item == get_snat6_rule():
-              if position != 0:
-                chain.delete_rule(get_snat6_rule())
-          table.commit()
-        table.autocommit = True
-      except:
-        print('Error running SNAT6, retrying...')
 
 def autopurge():
   while not quit_now:
@@ -451,6 +315,17 @@ def autopurge():
         if TIME_SINCE_LAST_ATTEMPT > NET_BAN_TIME or TIME_SINCE_LAST_ATTEMPT > MAX_BAN_TIME:
           unban(net)
 
+def mailcowChainOrder():
+  global lock
+  global quit_now
+  global exit_code
+  while not quit_now:
+    time.sleep(10)
+    with lock:
+      quit_now, exit_code = tables.checkIPv4ChainOrder()
+      if quit_now: return
+      quit_now, exit_code = tables.checkIPv6ChainOrder()
+
 def isIpNetwork(address):
   try:
     ipaddress.ip_network(address, False)
@@ -458,7 +333,6 @@ def isIpNetwork(address):
     return False
   return True
 
-
 def genNetworkList(list):
   resolver = dns.resolver.Resolver()
   hostnames = []
@@ -474,12 +348,12 @@ def genNetworkList(list):
       try:
         answer = resolver.resolve(qname=hostname, rdtype=rdtype, lifetime=3)
       except dns.exception.Timeout:
-        logInfo('Hostname %s timedout on resolve' % hostname)
+        logger.logInfo('Hostname %s timedout on resolve' % hostname)
         break
       except (dns.resolver.NXDOMAIN, dns.resolver.NoAnswer):
         continue
       except dns.exception.DNSException as dnsexception:
-        logInfo('%s' % dnsexception)
+        logger.logInfo('%s' % dnsexception)
         continue
       for rdata in answer:
         hostname_ips.append(rdata.to_text())
@@ -499,7 +373,7 @@ def whitelistUpdate():
     with lock:
       if Counter(new_whitelist) != Counter(WHITELIST):
         WHITELIST = new_whitelist
-        logInfo('Whitelist was changed, it has %s entries' % len(WHITELIST))
+        logger.logInfo('Whitelist was changed, it has %s entries' % len(WHITELIST))
     time.sleep(60.0 - ((time.time() - start_time) % 60.0))
 
 def blacklistUpdate():
@@ -515,7 +389,7 @@ def blacklistUpdate():
       addban = set(new_blacklist).difference(BLACKLIST)
       delban = set(BLACKLIST).difference(new_blacklist)
       BLACKLIST = new_blacklist
-      logInfo('Blacklist was changed, it has %s entries' % len(BLACKLIST))
+      logger.logInfo('Blacklist was changed, it has %s entries' % len(BLACKLIST))
       if addban:
         for net in addban:
           permBan(net=net)
@@ -524,40 +398,19 @@ def blacklistUpdate():
           permBan(net=net, unban=True)
     time.sleep(60.0 - ((time.time() - start_time) % 60.0))
 
-def initChain():
+def quit(signum, frame):
-  # Is called before threads start, no locking
+  global quit_now
-  print("Initializing mailcow netfilter chain")
+  quit_now = True
-  # IPv4
+
-  if not iptc.Chain(iptc.Table(iptc.Table.FILTER), "MAILCOW") in iptc.Table(iptc.Table.FILTER).chains:
-    iptc.Table(iptc.Table.FILTER).create_chain("MAILCOW")
-  for c in ['FORWARD', 'INPUT']:
-    chain = iptc.Chain(iptc.Table(iptc.Table.FILTER), c)
-    rule = iptc.Rule()
-    rule.src = '0.0.0.0/0'
-    rule.dst = '0.0.0.0/0'
-    target = iptc.Target(rule, "MAILCOW")
-    rule.target = target
-    if rule not in chain.rules:
-      chain.insert_rule(rule)
-  # IPv6
-  if not iptc.Chain(iptc.Table6(iptc.Table6.FILTER), "MAILCOW") in iptc.Table6(iptc.Table6.FILTER).chains:
-    iptc.Table6(iptc.Table6.FILTER).create_chain("MAILCOW")
-  for c in ['FORWARD', 'INPUT']:
-    chain = iptc.Chain(iptc.Table6(iptc.Table6.FILTER), c)
-    rule = iptc.Rule6()
-    rule.src = '::/0'
-    rule.dst = '::/0'
-    target = iptc.Target(rule, "MAILCOW")
-    rule.target = target
-    if rule not in chain.rules:
-      chain.insert_rule(rule)
 
 if __name__ == '__main__':
-
   # In case a previous session was killed without cleanup
   clear()
   # Reinit MAILCOW chain
-  initChain()
+  # Is called before threads start, no locking
+  logger.logInfo("Initializing mailcow netfilter chain")
+  tables.initChainIPv4()
+  tables.initChainIPv6()
 
   watch_thread = Thread(target=watch)
   watch_thread.daemon = True

data/Dockerfiles/netfilter/modules/IPTables.py

@@ -0,0 +1,213 @@
+import iptc
+import time
+
+class IPTables:
+  def __init__(self, chain_name, logger):
+    self.chain_name = chain_name
+    self.logger = logger
+
+  def initChainIPv4(self):
+    if not iptc.Chain(iptc.Table(iptc.Table.FILTER), self.chain_name) in iptc.Table(iptc.Table.FILTER).chains:
+      iptc.Table(iptc.Table.FILTER).create_chain(self.chain_name)
+    for c in ['FORWARD', 'INPUT']:
+      chain = iptc.Chain(iptc.Table(iptc.Table.FILTER), c)
+      rule = iptc.Rule()
+      rule.src = '0.0.0.0/0'
+      rule.dst = '0.0.0.0/0'
+      target = iptc.Target(rule, self.chain_name)
+      rule.target = target
+      if rule not in chain.rules:
+        chain.insert_rule(rule)
+
+  def initChainIPv6(self):
+    if not iptc.Chain(iptc.Table6(iptc.Table6.FILTER), self.chain_name) in iptc.Table6(iptc.Table6.FILTER).chains:
+      iptc.Table6(iptc.Table6.FILTER).create_chain(self.chain_name)
+    for c in ['FORWARD', 'INPUT']:
+      chain = iptc.Chain(iptc.Table6(iptc.Table6.FILTER), c)
+      rule = iptc.Rule6()
+      rule.src = '::/0'
+      rule.dst = '::/0'
+      target = iptc.Target(rule, self.chain_name)
+      rule.target = target
+      if rule not in chain.rules:
+        chain.insert_rule(rule)
+
+  def checkIPv4ChainOrder(self):
+    filter_table = iptc.Table(iptc.Table.FILTER)
+    filter_table.refresh()
+    return self.checkChainOrder(filter_table)
+
+  def checkIPv6ChainOrder(self):
+    filter_table = iptc.Table6(iptc.Table6.FILTER)
+    filter_table.refresh()
+    return self.checkChainOrder(filter_table)
+
+  def checkChainOrder(self, filter_table):
+    err = False
+    exit_code = None
+
+    forward_chain = iptc.Chain(filter_table, 'FORWARD')
+    input_chain = iptc.Chain(filter_table, 'INPUT')
+    for chain in [forward_chain, input_chain]:
+      target_found = False
+      for position, item in enumerate(chain.rules):
+        if item.target.name == self.chain_name:
+          target_found = True
+          if position > 2:
+            self.logger.logCrit('Error in %s chain: %s target not found, restarting container' % (chain.name, self.chain_name))
+            err = True
+            exit_code = 2
+      if not target_found:
+        self.logger.logCrit('Error in %s chain: %s target not found, restarting container' % (chain.name, self.chain_name))
+        err = True
+        exit_code = 2
+
+    return err, exit_code
+
+  def clearIPv4Table(self):
+    self.clearTable(iptc.Table(iptc.Table.FILTER))
+
+  def clearIPv6Table(self):
+    self.clearTable(iptc.Table6(iptc.Table6.FILTER))
+
+  def clearTable(self, filter_table):
+    filter_table.autocommit = False
+    forward_chain = iptc.Chain(filter_table, "FORWARD")
+    input_chain = iptc.Chain(filter_table, "INPUT")
+    mailcow_chain = iptc.Chain(filter_table, self.chain_name)
+    if mailcow_chain in filter_table.chains:
+      for rule in mailcow_chain.rules:
+        mailcow_chain.delete_rule(rule)
+      for rule in forward_chain.rules:
+        if rule.target.name == self.chain_name:
+          forward_chain.delete_rule(rule)
+      for rule in input_chain.rules:
+        if rule.target.name == self.chain_name:
+          input_chain.delete_rule(rule)
+      filter_table.delete_chain(self.chain_name)
+    filter_table.commit()
+    filter_table.refresh()
+    filter_table.autocommit = True
+
+  def banIPv4(self, source):
+    chain = iptc.Chain(iptc.Table(iptc.Table.FILTER), self.chain_name)
+    rule = iptc.Rule()
+    rule.src = source
+    target = iptc.Target(rule, "REJECT")
+    rule.target = target
+    if rule in chain.rules:
+      return False
+    chain.insert_rule(rule)
+    return True
+
+  def banIPv6(self, source):
+    chain = iptc.Chain(iptc.Table6(iptc.Table6.FILTER), self.chain_name)
+    rule = iptc.Rule6()
+    rule.src = source
+    target = iptc.Target(rule, "REJECT")
+    rule.target = target
+    if rule in chain.rules:
+      return False
+    chain.insert_rule(rule)
+    return True
+
+  def unbanIPv4(self, source):
+    chain = iptc.Chain(iptc.Table(iptc.Table.FILTER), self.chain_name)
+    rule = iptc.Rule()
+    rule.src = source
+    target = iptc.Target(rule, "REJECT")
+    rule.target = target
+    if rule not in chain.rules: 
+      return False
+    chain.delete_rule(rule)
+    return True
+
+  def unbanIPv6(self, source):
+    chain = iptc.Chain(iptc.Table6(iptc.Table6.FILTER), self.chain_name)
+    rule = iptc.Rule6()
+    rule.src = source
+    target = iptc.Target(rule, "REJECT")
+    rule.target = target
+    if rule not in chain.rules:
+      return False
+    chain.delete_rule(rule)
+    return True
+
+  def snat4(self, snat_target, source):
+    try:
+      table = iptc.Table('nat')
+      table.refresh()
+      chain = iptc.Chain(table, 'POSTROUTING')
+      table.autocommit = False
+      new_rule = self.getSnat4Rule(snat_target, source)
+
+      if not chain.rules:
+        # if there are no rules in the chain, insert the new rule directly
+        self.logger.logInfo(f'Added POSTROUTING rule for source network {new_rule.src} to SNAT target {snat_target}')
+        chain.insert_rule(new_rule)
+      else:
+        for position, rule in enumerate(chain.rules):
+          if not hasattr(rule.target, 'parameter'):
+              continue
+          match = all((
+            new_rule.get_src() == rule.get_src(),
+            new_rule.get_dst() == rule.get_dst(),
+            new_rule.target.parameters == rule.target.parameters,
+            new_rule.target.name == rule.target.name
+          ))
+          if position == 0:
+            if not match:
+              self.logger.logInfo(f'Added POSTROUTING rule for source network {new_rule.src} to SNAT target {snat_target}')
+              chain.insert_rule(new_rule)
+          else:
+            if match:
+              self.logger.logInfo(f'Remove rule for source network {new_rule.src} to SNAT target {snat_target} from POSTROUTING chain at position {position}')
+              chain.delete_rule(rule)
+
+      table.commit()
+      table.autocommit = True
+      return True
+    except:
+      self.logger.logCrit('Error running SNAT4, retrying...')
+      return False
+
+  def snat6(self, snat_target, source):
+    try:
+      table = iptc.Table6('nat')
+      table.refresh()
+      chain = iptc.Chain(table, 'POSTROUTING')
+      table.autocommit = False
+      new_rule = self.getSnat6Rule(snat_target, source)
+
+      if new_rule not in chain.rules:
+        self.logger.logInfo('Added POSTROUTING rule for source network %s to SNAT target %s' % (new_rule.src, snat_target))
+        chain.insert_rule(new_rule)
+      else:
+        for position, item in enumerate(chain.rules):
+          if item == new_rule:
+            if position != 0:
+              chain.delete_rule(new_rule)
+    
+      table.commit()
+      table.autocommit = True
+    except:
+      self.logger.logCrit('Error running SNAT6, retrying...')
+
+
+  def getSnat4Rule(self, snat_target, source):
+    rule = iptc.Rule()
+    rule.src = source
+    rule.dst = '!' + rule.src
+    target = rule.create_target("SNAT")
+    target.to_source = snat_target
+    match = rule.create_match("comment")
+    match.comment = f'{int(round(time.time()))}'
+    return rule
+
+  def getSnat6Rule(self, snat_target, source):
+    rule = iptc.Rule6()
+    rule.src = source
+    rule.dst = '!' + rule.src
+    target = rule.create_target("SNAT")
+    target.to_source = snat_target
+    return rule

data/Dockerfiles/netfilter/modules/Logger.py

@@ -0,0 +1,23 @@
+import time
+import json
+
+class Logger:
+  def __init__(self, redis):
+    self.r = redis
+
+  def log(self, priority, message):
+    tolog = {}
+    tolog['time'] = int(round(time.time()))
+    tolog['priority'] = priority
+    tolog['message'] = message
+    self.r.lpush('NETFILTER_LOG', json.dumps(tolog, ensure_ascii=False))
+    print(message)
+
+  def logWarn(self, message):
+    self.log('warn', message)
+
+  def logCrit(self, message):
+    self.log('crit', message)
+
+  def logInfo(self, message):
+    self.log('info', message)

data/Dockerfiles/netfilter/modules/NFTables.py

@@ -0,0 +1,495 @@
+import nftables
+import ipaddress
+
+class NFTables:
+  def __init__(self, chain_name, logger):
+    self.chain_name = chain_name
+    self.logger = logger
+
+    self.nft = nftables.Nftables()
+    self.nft.set_json_output(True)
+    self.nft.set_handle_output(True)
+    self.nft_chain_names = {'ip': {'filter': {'input': '', 'forward': ''}, 'nat': {'postrouting': ''} },
+                            'ip6': {'filter': {'input': '', 'forward': ''}, 'nat': {'postrouting': ''} } }
+
+    self.search_current_chains()
+
+  def initChainIPv4(self):
+    self.insert_mailcow_chains("ip")
+
+  def initChainIPv6(self):
+    self.insert_mailcow_chains("ip6")
+
+  def checkIPv4ChainOrder(self):
+    return self.checkChainOrder("ip")
+
+  def checkIPv6ChainOrder(self):
+    return self.checkChainOrder("ip6")
+
+  def checkChainOrder(self, filter_table):
+    err = False
+    exit_code = None
+
+    for chain in ['input', 'forward']:
+      chain_position = self.check_mailcow_chains(filter_table, chain)
+      if chain_position is None: continue
+
+      if chain_position is False:
+        self.logger.logCrit(f'MAILCOW target not found in {filter_table} {chain} table, restarting container to fix it...')
+        err = True
+        exit_code = 2
+
+      if chain_position > 0:
+        self.logger.logCrit(f'MAILCOW target is in position {chain_position} in the {filter_table} {chain} table, restarting container to fix it...')
+        err = True
+        exit_code = 2
+
+    return err, exit_code
+
+  def clearIPv4Table(self):
+    self.clearTable("ip")
+
+  def clearIPv6Table(self):
+    self.clearTable("ip6")
+
+  def clearTable(self, _family):
+    is_empty_dict = True
+    json_command = self.get_base_dict()
+    chain_handle = self.get_chain_handle(_family, "filter", self.chain_name)
+    # if no handle, the chain doesn't exists
+    if chain_handle is not None:
+      is_empty_dict = False
+      # flush chain
+      mailcow_chain = {'family': _family, 'table': 'filter', 'name': self.chain_name}
+      flush_chain = {'flush': {'chain': mailcow_chain}}
+      json_command["nftables"].append(flush_chain)
+
+    # remove rule in forward chain
+    # remove rule in input chain
+    chains_family = [self.nft_chain_names[_family]['filter']['input'],
+                    self.nft_chain_names[_family]['filter']['forward'] ]
+
+    for chain_base in chains_family:
+      if not chain_base: continue
+
+      rules_handle = self.get_rules_handle(_family, "filter", chain_base)
+      if rules_handle is not None:
+        for r_handle in rules_handle:
+          is_empty_dict = False
+          mailcow_rule = {'family':_family,
+                          'table': 'filter',
+                          'chain': chain_base,
+                          'handle': r_handle }
+          delete_rules = {'delete': {'rule': mailcow_rule} }
+          json_command["nftables"].append(delete_rules)
+
+    # remove chain
+    # after delete all rules referencing this chain
+    if chain_handle is not None:
+      mc_chain_handle = {'family':_family,
+                        'table': 'filter',
+                        'name': self.chain_name,
+                        'handle': chain_handle }
+      delete_chain = {'delete': {'chain': mc_chain_handle} }
+      json_command["nftables"].append(delete_chain)
+
+    if is_empty_dict == False:
+      if self.nft_exec_dict(json_command):
+        self.logger.logInfo(f"Clear completed: {_family}")
+
+  def banIPv4(self, source):
+    ban_dict = self.get_ban_ip_dict(source, "ip")
+    return self.nft_exec_dict(ban_dict)
+
+  def banIPv6(self, source):
+    ban_dict = self.get_ban_ip_dict(source, "ip6")
+    return self.nft_exec_dict(ban_dict)
+
+  def unbanIPv4(self, source):
+    unban_dict = self.get_unban_ip_dict(source, "ip")
+    if not unban_dict:
+      return False
+    return self.nft_exec_dict(unban_dict)
+
+  def unbanIPv6(self, source):
+    unban_dict = self.get_unban_ip_dict(source, "ip6")
+    if not unban_dict:
+      return False
+    return self.nft_exec_dict(unban_dict)
+
+  def snat4(self, snat_target, source):
+    self.snat_rule("ip", snat_target, source)
+
+  def snat6(self, snat_target, source):
+    self.snat_rule("ip6", snat_target, source)
+
+
+  def nft_exec_dict(self, query: dict):
+    if not query: return False
+
+    rc, output, error = self.nft.json_cmd(query)
+    if rc != 0:
+      #self.logger.logCrit(f"Nftables Error: {error}")
+      return False
+
+    # Prevent returning False or empty string on commands that do not produce output
+    if rc == 0 and len(output) == 0:
+      return True
+
+    return output
+
+  def get_base_dict(self):
+    return {'nftables': [{ 'metainfo': { 'json_schema_version': 1} } ] }
+
+  def search_current_chains(self):
+    nft_chain_priority = {'ip': {'filter': {'input': None, 'forward': None}, 'nat': {'postrouting': None} },
+                      'ip6': {'filter': {'input': None, 'forward': None}, 'nat': {'postrouting': None} } }
+
+    # Command: 'nft list chains'
+    _list = {'list' : {'chains': 'null'} }
+    command = self.get_base_dict()
+    command['nftables'].append(_list)
+    kernel_ruleset = self.nft_exec_dict(command)
+    if kernel_ruleset:
+      for _object in kernel_ruleset['nftables']:
+        chain = _object.get("chain")
+        if not chain: continue
+
+        _family = chain['family']
+        _table = chain['table']
+        _hook = chain.get("hook")
+        _priority = chain.get("prio")
+        _name = chain['name']
+
+        if _family not in self.nft_chain_names: continue
+        if _table not in self.nft_chain_names[_family]: continue
+        if _hook not in self.nft_chain_names[_family][_table]: continue
+        if _priority is None: continue
+
+        _saved_priority = nft_chain_priority[_family][_table][_hook]
+        if _saved_priority is None or _priority < _saved_priority:
+          # at this point, we know the chain has:
+          # hook and priority set
+          # and it has the lowest priority
+          nft_chain_priority[_family][_table][_hook] = _priority
+          self.nft_chain_names[_family][_table][_hook] = _name
+
+  def search_for_chain(self, kernel_ruleset: dict, chain_name: str):
+    found = False
+    for _object in kernel_ruleset["nftables"]:
+      chain = _object.get("chain")
+      if not chain:
+        continue
+      ch_name = chain.get("name")
+      if ch_name == chain_name:
+        found = True
+        break
+    return found
+
+  def get_chain_dict(self, _family: str, _name: str):
+    # nft (add | create) chain [<family>] <table> <name> 
+    _chain_opts = {'family': _family, 'table': 'filter', 'name': _name  }
+    _add = {'add': {'chain': _chain_opts} }
+    final_chain = self.get_base_dict()
+    final_chain["nftables"].append(_add)
+    return final_chain
+
+  def get_mailcow_jump_rule_dict(self, _family: str, _chain: str):
+    _jump_rule = self.get_base_dict()
+    _expr_opt=[]
+    _expr_counter = {'family': _family, 'table': 'filter', 'packets': 0, 'bytes': 0}
+    _counter_dict = {'counter': _expr_counter}
+    _expr_opt.append(_counter_dict)
+
+    _jump_opts = {'jump': {'target': self.chain_name} }
+
+    _expr_opt.append(_jump_opts)
+
+    _rule_params = {'family': _family,
+                    'table': 'filter',
+                    'chain': _chain,
+                    'expr': _expr_opt,
+                    'comment': "mailcow" }
+
+    _add_rule = {'insert': {'rule': _rule_params} }
+
+    _jump_rule["nftables"].append(_add_rule)
+
+    return _jump_rule
+
+  def insert_mailcow_chains(self, _family: str):
+    nft_input_chain = self.nft_chain_names[_family]['filter']['input']
+    nft_forward_chain = self.nft_chain_names[_family]['filter']['forward']
+    # Command: 'nft list table <family> filter'
+    _table_opts = {'family': _family, 'name': 'filter'}
+    _list = {'list': {'table': _table_opts} }
+    command = self.get_base_dict()
+    command['nftables'].append(_list)
+    kernel_ruleset = self.nft_exec_dict(command)
+    if kernel_ruleset:
+      # chain
+      if not self.search_for_chain(kernel_ruleset, self.chain_name):
+        cadena = self.get_chain_dict(_family, self.chain_name)
+        if self.nft_exec_dict(cadena):
+          self.logger.logInfo(f"MAILCOW {_family} chain created successfully.")
+
+      input_jump_found, forward_jump_found = False, False
+
+      for _object in kernel_ruleset["nftables"]:
+        if not _object.get("rule"):
+          continue
+
+        rule = _object["rule"]
+        if nft_input_chain and rule["chain"] == nft_input_chain:
+          if rule.get("comment") and rule["comment"] == "mailcow":
+            input_jump_found = True
+        if nft_forward_chain and rule["chain"] == nft_forward_chain:
+          if rule.get("comment") and rule["comment"] == "mailcow":
+            forward_jump_found = True
+
+      if not input_jump_found:
+        command = self.get_mailcow_jump_rule_dict(_family, nft_input_chain)
+        self.nft_exec_dict(command)
+
+      if not forward_jump_found:
+        command = self.get_mailcow_jump_rule_dict(_family, nft_forward_chain)
+        self.nft_exec_dict(command)
+
+  def delete_nat_rule(self, _family:str, _chain: str, _handle:str):
+    delete_command = self.get_base_dict()
+    _rule_opts = {'family': _family,
+                  'table': 'nat',
+                  'chain': _chain,
+                  'handle': _handle  }
+    _delete = {'delete': {'rule': _rule_opts} }
+    delete_command["nftables"].append(_delete)
+
+    return self.nft_exec_dict(delete_command)
+
+  def snat_rule(self, _family: str, snat_target: str, source_address: str):
+    chain_name = self.nft_chain_names[_family]['nat']['postrouting']
+
+    # no postrouting chain, may occur if docker has ipv6 disabled.
+    if not chain_name: return
+
+    # Command: nft list chain <family> nat <chain_name>
+    _chain_opts = {'family': _family, 'table': 'nat', 'name': chain_name}
+    _list = {'list':{'chain': _chain_opts} }
+    command = self.get_base_dict()
+    command['nftables'].append(_list)
+    kernel_ruleset = self.nft_exec_dict(command)
+    if not kernel_ruleset:
+      return
+
+    rule_position = 0
+    rule_handle = None
+    rule_found = False
+    for _object in kernel_ruleset["nftables"]:
+      if not _object.get("rule"):
+        continue
+
+      rule = _object["rule"]
+      if not rule.get("comment") or not rule["comment"] == "mailcow":
+        rule_position +=1
+        continue
+
+      rule_found = True
+      rule_handle = rule["handle"]
+      break
+
+    dest_net = ipaddress.ip_network(source_address)
+    target_net = ipaddress.ip_network(snat_target)
+
+    if rule_found:
+      saddr_ip = rule["expr"][0]["match"]["right"]["prefix"]["addr"]
+      saddr_len = int(rule["expr"][0]["match"]["right"]["prefix"]["len"])
+
+      daddr_ip = rule["expr"][1]["match"]["right"]["prefix"]["addr"]
+      daddr_len = int(rule["expr"][1]["match"]["right"]["prefix"]["len"])
+
+      target_ip = rule["expr"][3]["snat"]["addr"]
+
+      saddr_net = ipaddress.ip_network(saddr_ip + '/' + str(saddr_len))
+      daddr_net = ipaddress.ip_network(daddr_ip + '/' + str(daddr_len))
+      current_target_net = ipaddress.ip_network(target_ip)
+
+      match = all((
+                dest_net == saddr_net,
+                dest_net == daddr_net,
+                target_net == current_target_net
+              ))
+      try:
+        if rule_position == 0:
+          if not match:
+            # Position 0 , it is a mailcow rule , but it does not have the same parameters
+            if self.delete_nat_rule(_family, chain_name, rule_handle):
+              self.logger.logInfo(f'Remove rule for source network {saddr_net} to SNAT target {target_net} from {_family} nat {chain_name} chain, rule does not match configured parameters')
+        else:
+          # Position > 0 and is mailcow rule
+          if self.delete_nat_rule(_family, chain_name, rule_handle):
+            self.logger.logInfo(f'Remove rule for source network {saddr_net} to SNAT target {target_net} from {_family} nat {chain_name} chain, rule is at position {rule_position}')
+      except:
+          self.logger.logCrit(f"Error running SNAT on {_family}, retrying..." )
+    else:
+      # rule not found
+      json_command = self.get_base_dict()
+      try:
+        snat_dict = {'snat': {'addr': str(target_net.network_address)} }
+
+        expr_counter = {'family': _family, 'table': 'nat', 'packets': 0, 'bytes': 0}
+        counter_dict = {'counter': expr_counter}
+
+        prefix_dict = {'prefix': {'addr': str(dest_net.network_address), 'len': int(dest_net.prefixlen)} }
+        payload_dict = {'payload': {'protocol': _family, 'field': "saddr"} }
+        match_dict1 = {'match': {'op': '==', 'left': payload_dict, 'right': prefix_dict} }
+
+        payload_dict2 = {'payload': {'protocol': _family, 'field': "daddr"} }
+        match_dict2 = {'match': {'op': '!=', 'left': payload_dict2, 'right': prefix_dict } }
+        expr_list = [
+                    match_dict1,
+                    match_dict2,
+                    counter_dict,
+                    snat_dict
+                    ]
+        rule_fields = {'family': _family,
+                        'table': 'nat',
+                        'chain': chain_name,
+                        'comment': "mailcow",
+                        'expr': expr_list }
+
+        insert_dict = {'insert': {'rule': rule_fields} }
+        json_command["nftables"].append(insert_dict)
+        if self.nft_exec_dict(json_command):
+          self.logger.logInfo(f'Added {_family} nat {chain_name} rule for source network {dest_net} to {target_net}')
+      except:
+        self.logger.logCrit(f"Error running SNAT on {_family}, retrying...")
+
+  def get_chain_handle(self, _family: str, _table: str, chain_name: str):
+    chain_handle = None
+    # Command: 'nft list chains {family}'
+    _list = {'list': {'chains': {'family': _family} } }
+    command = self.get_base_dict()
+    command['nftables'].append(_list)
+    kernel_ruleset = self.nft_exec_dict(command)
+    if kernel_ruleset:
+      for _object in kernel_ruleset["nftables"]:
+        if not _object.get("chain"):
+          continue
+        chain = _object["chain"]
+        if chain["family"] == _family and chain["table"] == _table and chain["name"] == chain_name:
+          chain_handle = chain["handle"]
+          break
+    return chain_handle
+
+  def get_rules_handle(self, _family: str, _table: str, chain_name: str):
+    rule_handle = []
+    # Command: 'nft list chain {family} {table} {chain_name}'
+    _chain_opts = {'family': _family, 'table': _table, 'name': chain_name}
+    _list = {'list': {'chain': _chain_opts} }
+    command = self.get_base_dict()
+    command['nftables'].append(_list)
+
+    kernel_ruleset = self.nft_exec_dict(command)
+    if kernel_ruleset:
+      for _object in kernel_ruleset["nftables"]:
+        if not _object.get("rule"):
+          continue
+
+        rule = _object["rule"]
+        if rule["family"] == _family and rule["table"] == _table and rule["chain"] == chain_name:
+          if rule.get("comment") and rule["comment"] == "mailcow":
+            rule_handle.append(rule["handle"])
+    return rule_handle
+
+  def get_ban_ip_dict(self, ipaddr: str, _family: str):
+    json_command = self.get_base_dict()
+
+    expr_opt = []
+    ipaddr_net = ipaddress.ip_network(ipaddr)
+    right_dict = {'prefix': {'addr': str(ipaddr_net.network_address), 'len': int(ipaddr_net.prefixlen) } }
+
+    left_dict = {'payload': {'protocol': _family, 'field': 'saddr'} }
+    match_dict = {'op': '==', 'left': left_dict, 'right': right_dict }
+    expr_opt.append({'match': match_dict})
+
+    counter_dict = {'counter': {'family': _family, 'table': "filter", 'packets': 0, 'bytes': 0} }
+    expr_opt.append(counter_dict)
+
+    expr_opt.append({'drop': "null"})
+
+    rule_dict = {'family': _family, 'table': "filter", 'chain': self.chain_name, 'expr': expr_opt}
+
+    base_dict = {'insert': {'rule': rule_dict} }
+    json_command["nftables"].append(base_dict)
+
+    return json_command
+
+  def get_unban_ip_dict(self, ipaddr:str, _family: str):
+    json_command = self.get_base_dict()
+    # Command: 'nft list chain {s_family} filter  MAILCOW'
+    _chain_opts = {'family': _family, 'table': 'filter', 'name': self.chain_name}
+    _list = {'list': {'chain': _chain_opts} }
+    command = self.get_base_dict()
+    command['nftables'].append(_list)
+    kernel_ruleset = self.nft_exec_dict(command)
+    rule_handle = None
+    if kernel_ruleset:
+      for _object in kernel_ruleset["nftables"]:
+        if not _object.get("rule"):
+          continue
+
+        rule = _object["rule"]["expr"][0]["match"]
+        left_opt = rule["left"]["payload"]
+        if not left_opt["protocol"] == _family:
+          continue
+        if not left_opt["field"] =="saddr":
+          continue
+
+        # ip currently banned
+        rule_right = rule["right"]
+        if isinstance(rule_right, dict):
+          current_rule_ip = rule_right["prefix"]["addr"] + '/' + str(rule_right["prefix"]["len"])
+        else:
+          current_rule_ip = rule_right
+        current_rule_net = ipaddress.ip_network(current_rule_ip)
+
+        # ip to ban
+        candidate_net = ipaddress.ip_network(ipaddr)
+
+        if current_rule_net == candidate_net:
+          rule_handle = _object["rule"]["handle"]
+          break
+
+      if rule_handle is not None:
+        mailcow_rule = {'family': _family, 'table': 'filter', 'chain': self.chain_name, 'handle': rule_handle}
+        delete_rule = {'delete': {'rule': mailcow_rule} }
+        json_command["nftables"].append(delete_rule)
+      else:
+        return False
+
+    return json_command
+
+  def check_mailcow_chains(self, family: str, chain: str):
+    position = 0
+    rule_found = False
+    chain_name = self.nft_chain_names[family]['filter'][chain]
+
+    if not chain_name: return None
+
+    _chain_opts = {'family': family, 'table': 'filter', 'name': chain_name}
+    _list = {'list': {'chain': _chain_opts}}
+    command = self.get_base_dict()
+    command['nftables'].append(_list)
+    kernel_ruleset = self.nft_exec_dict(command)
+    if kernel_ruleset:
+      for _object in kernel_ruleset["nftables"]:
+        if not _object.get("rule"):
+          continue
+        rule = _object["rule"]
+        if rule.get("comment") and rule["comment"] == "mailcow":
+          rule_found = True
+          break
+
+        position+=1
+
+    return position if rule_found else False

docker-compose.yml

@@ -434,7 +434,7 @@ services:
             - acme
 
     netfilter-mailcow:
-      image: mailcow/netfilter:1.52
+      image: mailcow/netfilter:1.53
       stop_grace_period: 30s
       depends_on:
         - dovecot-mailcow