firewall: T5729: T5681: T5217: backport subsystem from current branch

This is a combined backport for all accumulated changes done to the firewall
subsystem on the current branch.

5 files changed, 49 insertions, 126 deletions

diff --git a/src/conf_mode/firewall.py b/src/conf_mode/firewall.py
index ee19555c4..acb7dfa41 100755
--- a/src/conf_mode/firewall.py
+++ b/src/conf_mode/firewall.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 #
-# Copyright (C) 2021-2022 VyOS maintainers and contributors
+# Copyright (C) 2021-2023 VyOS maintainers and contributors
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 or later as
@@ -39,6 +39,7 @@ from vyos.utils.process import process_named_running
 from vyos.utils.process import rc_cmd
 from vyos import ConfigError
 from vyos import airbag
+
 airbag.enable()
 
 nftables_conf = '/run/nftables.conf'
@@ -98,7 +99,7 @@ def geoip_updated(conf, firewall):
         elif (path[0] == 'ipv6'):
             set_name = f'GEOIP_CC6_{path[1]}_{path[2]}_{path[4]}'
             out['ipv6_name'].append(set_name)
-            
+
         updated = True
 
     if 'delete' in node_diff:
@@ -138,6 +139,8 @@ def get_config(config=None):
 
     fqdn_config_parse(firewall)
 
+    set_dependents('conntrack', conf)
+
     return firewall
 
 def verify_rule(firewall, rule_conf, ipv6):
@@ -167,6 +170,16 @@ def verify_rule(firewall, rule_conf, ipv6):
         if not dict_search_args(firewall, 'flowtable', offload_target):
             raise ConfigError(f'Invalid offload-target. Flowtable "{offload_target}" does not exist on the system')
 
+    if rule_conf['action'] != 'synproxy' and 'synproxy' in rule_conf:
+        raise ConfigError('"synproxy" option allowed only for action synproxy')
+    if rule_conf['action'] == 'synproxy':
+        if 'state' in rule_conf:
+            raise ConfigError('For action "synproxy" state cannot be defined')
+        if not rule_conf.get('synproxy', {}).get('tcp'):
+            raise ConfigError('synproxy TCP MSS is not defined')
+        if rule_conf.get('protocol', {}) != 'tcp':
+            raise ConfigError('For action "synproxy" the protocol must be set to TCP')
+
     if 'queue_options' in rule_conf:
         if 'queue' not in rule_conf['action']:
             raise ConfigError('queue-options defined, but action queue needed and it is not defined')
@@ -434,17 +447,6 @@ def generate(firewall):
                 if local_zone in zone_conf['from']:
                     local_zone_conf['from_local'][zone] = zone_conf['from'][local_zone]
 
-    # Determine if conntrack is needed
-    firewall['ipv4_conntrack_action'] = 'return'
-    firewall['ipv6_conntrack_action'] = 'return'
-
-    for rules, path in dict_search_recursive(firewall, 'rule'):
-        if any(('state' in rule_conf or 'connection_status' in rule_conf) for rule_conf in rules.values()):
-            if path[0] == 'ipv4':
-                firewall['ipv4_conntrack_action'] = 'accept'
-            elif path[0] == 'ipv6':
-                firewall['ipv6_conntrack_action'] = 'accept'
-
     render(nftables_conf, 'firewall/nftables.j2', firewall)
     return None
 
@@ -474,8 +476,7 @@ def apply(firewall):
 
     apply_sysfs(firewall)
 
-    if firewall['group_resync']:
-        call_dependents()
+    call_dependents()
 
     # T970 Enable a resolver (systemd daemon) that checks
     # domain-group/fqdn addresses and update entries for domains by timeout
diff --git a/src/conf_mode/load-balancing_wan.py b/src/conf_mode/load-balancing_wan.py
index ad9c80d72..5da0b906b 100755
--- a/src/conf_mode/load-balancing_wan.py
+++ b/src/conf_mode/load-balancing_wan.py
@@ -21,6 +21,7 @@ from shutil import rmtree
 
 from vyos.base import Warning
 from vyos.config import Config
+from vyos.configdep import set_dependents, call_dependents
 from vyos.utils.process import cmd
 from vyos.template import render
 from vyos import ConfigError
@@ -49,6 +50,8 @@ def get_config(config=None):
         if lb.from_defaults(['rule', rule, 'limit']):
             del lb['rule'][rule]['limit']
 
+    set_dependents('conntrack', conf)
+
     return lb
 
 
@@ -132,6 +135,8 @@ def apply(lb):
         cmd('sudo sysctl -w net.netfilter.nf_conntrack_acct=1')
         cmd(f'systemctl restart {systemd_service}')
 
+    call_dependents()
+
     return None
 
 
diff --git a/src/conf_mode/nat.py b/src/conf_mode/nat.py
index ffd4a33e7..bd9b5162c 100755
--- a/src/conf_mode/nat.py
+++ b/src/conf_mode/nat.py
@@ -18,13 +18,12 @@ import jmespath
 import json
 import os
 
-from distutils.version import LooseVersion
-from platform import release as kernel_version
 from sys import exit
 from netifaces import interfaces
 
 from vyos.base import Warning
 from vyos.config import Config
+from vyos.configdep import set_dependents, call_dependents
 from vyos.template import render
 from vyos.template import is_ip_network
 from vyos.utils.kernel import check_kmod
@@ -38,10 +37,7 @@ from vyos import ConfigError
 from vyos import airbag
 airbag.enable()
 
-if LooseVersion(kernel_version()) > LooseVersion('5.1'):
-    k_mod = ['nft_nat', 'nft_chain_nat']
-else:
-    k_mod = ['nft_nat', 'nft_chain_nat_ipv4']
+k_mod = ['nft_nat', 'nft_chain_nat']
 
 nftables_nat_config = '/run/nftables_nat.conf'
 nftables_static_nat_conf = '/run/nftables_static-nat-rules.nft'
@@ -53,18 +49,27 @@ valid_groups = [
     'port_group'
 ]
 
-def get_handler(json, chain, target):
-    """ Get nftable rule handler number of given chain/target combination.
-    Handler is required when adding NAT/Conntrack helper targets """
-    for x in json:
-        if x['chain'] != chain:
-            continue
-        if x['target'] != target:
-            continue
-        return x['handle']
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
 
-    return None
+    base = ['nat']
+    nat = conf.get_config_dict(base, key_mangling=('-', '_'),
+                               get_first_key=True,
+                               with_recursive_defaults=True)
 
+    set_dependents('conntrack', conf)
+
+    if not conf.exists(base):
+        nat['deleted'] = ''
+        return nat
+
+    nat['firewall_group'] = conf.get_config_dict(['firewall', 'group'], key_mangling=('-', '_'), get_first_key=True,
+                                    no_tag_node_value_mangle=True)
+
+    return nat
 
 def verify_rule(config, err_msg, groups_dict):
     """ Common verify steps used for both source and destination NAT """
@@ -105,7 +110,7 @@ def verify_rule(config, err_msg, groups_dict):
                         group_obj = dict_search_args(groups_dict, group, group_name)
 
                         if group_obj is None:
-                            raise ConfigError(f'Invalid {error_group} "{group_name}" on firewall rule')
+                            raise ConfigError(f'Invalid {error_group} "{group_name}" on nat rule')
 
                         if not group_obj:
                             Warning(f'{error_group} "{group_name}" has no members!')
@@ -129,62 +134,11 @@ def verify_rule(config, err_msg, groups_dict):
             if count != 100:
                 Warning(f'Sum of weight for nat load balance rule is not 100. You may get unexpected behaviour')
 
-def get_config(config=None):
-    if config:
-        conf = config
-    else:
-        conf = Config()
-
-    base = ['nat']
-    nat = conf.get_config_dict(base, key_mangling=('-', '_'),
-                               get_first_key=True,
-                               with_recursive_defaults=True)
-
-    # read in current nftable (once) for further processing
-    tmp = cmd('nft -j list table raw')
-    nftable_json = json.loads(tmp)
-
-    # condense the full JSON table into a list with only relevand informations
-    pattern = 'nftables[?rule].rule[?expr[].jump].{chain: chain, handle: handle, target: expr[].jump.target | [0]}'
-    condensed_json = jmespath.search(pattern, nftable_json)
-
-    if not conf.exists(base):
-        if get_handler(condensed_json, 'PREROUTING', 'VYOS_CT_HELPER'):
-            nat['helper_functions'] = 'remove'
-
-            # Retrieve current table handler positions
-            nat['pre_ct_ignore'] = get_handler(condensed_json, 'PREROUTING', 'VYOS_CT_HELPER')
-            nat['pre_ct_conntrack'] = get_handler(condensed_json, 'PREROUTING', 'NAT_CONNTRACK')
-            nat['out_ct_ignore'] = get_handler(condensed_json, 'OUTPUT', 'VYOS_CT_HELPER')
-            nat['out_ct_conntrack'] = get_handler(condensed_json, 'OUTPUT', 'NAT_CONNTRACK')
-        nat['deleted'] = ''
-        return nat
-
-    nat['firewall_group'] = conf.get_config_dict(['firewall', 'group'], key_mangling=('-', '_'), get_first_key=True,
-                                    no_tag_node_value_mangle=True)
-
-    # check if NAT connection tracking helpers need to be set up - this has to
-    # be done only once
-    if not get_handler(condensed_json, 'PREROUTING', 'NAT_CONNTRACK'):
-        nat['helper_functions'] = 'add'
-
-        # Retrieve current table handler positions
-        nat['pre_ct_ignore'] = get_handler(condensed_json, 'PREROUTING', 'VYOS_CT_IGNORE')
-        nat['pre_ct_conntrack'] = get_handler(condensed_json, 'PREROUTING', 'VYOS_CT_PREROUTING_HOOK')
-        nat['out_ct_ignore'] = get_handler(condensed_json, 'OUTPUT', 'VYOS_CT_IGNORE')
-        nat['out_ct_conntrack'] = get_handler(condensed_json, 'OUTPUT', 'VYOS_CT_OUTPUT_HOOK')
-
-    return nat
-
 def verify(nat):
     if not nat or 'deleted' in nat:
         # no need to verify the CLI as NAT is going to be deactivated
         return None
 
-    if 'helper_functions' in nat:
-        if not (nat['pre_ct_ignore'] or nat['pre_ct_conntrack'] or nat['out_ct_ignore'] or nat['out_ct_conntrack']):
-            raise Exception('could not determine nftable ruleset handlers')
-
     if dict_search('source.rule', nat):
         for rule, config in dict_search('source.rule', nat).items():
             err_msg = f'Source NAT configuration error in rule {rule}:'
@@ -265,6 +219,8 @@ def apply(nat):
         os.unlink(nftables_nat_config)
         os.unlink(nftables_static_nat_conf)
 
+    call_dependents()
+
     return None
 
 if __name__ == '__main__':
diff --git a/src/conf_mode/nat66.py b/src/conf_mode/nat66.py
index ed716b2a2..4c1ead258 100755
--- a/src/conf_mode/nat66.py
+++ b/src/conf_mode/nat66.py
@@ -23,6 +23,7 @@ from netifaces import interfaces
 
 from vyos.base import Warning
 from vyos.config import Config
+from vyos.configdep import set_dependents, call_dependents
 from vyos.template import render
 from vyos.utils.process import cmd
 from vyos.utils.kernel import check_kmod
@@ -36,18 +37,6 @@ k_mod = ['nft_nat', 'nft_chain_nat']
 
 nftables_nat66_config = '/run/nftables_nat66.nft'
 
-def get_handler(json, chain, target):
-    """ Get nftable rule handler number of given chain/target combination.
-    Handler is required when adding NAT66/Conntrack helper targets """
-    for x in json:
-        if x['chain'] != chain:
-            continue
-        if x['target'] != target:
-            continue
-        return x['handle']
-
-    return None
-
 def get_config(config=None):
     if config:
         conf = config
@@ -57,35 +46,10 @@ def get_config(config=None):
     base = ['nat66']
     nat = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)
 
-    # read in current nftable (once) for further processing
-    tmp = cmd('nft -j list table ip6 raw')
-    nftable_json = json.loads(tmp)
-
-    # condense the full JSON table into a list with only relevand informations
-    pattern = 'nftables[?rule].rule[?expr[].jump].{chain: chain, handle: handle, target: expr[].jump.target | [0]}'
-    condensed_json = jmespath.search(pattern, nftable_json)
+    set_dependents('conntrack', conf)
 
     if not conf.exists(base):
-        nat['helper_functions'] = 'remove'
-        nat['pre_ct_ignore'] = get_handler(condensed_json, 'PREROUTING', 'VYOS_CT_HELPER')
-        nat['pre_ct_conntrack'] = get_handler(condensed_json, 'PREROUTING', 'NAT_CONNTRACK')
-        nat['out_ct_ignore'] = get_handler(condensed_json, 'OUTPUT', 'VYOS_CT_HELPER')
-        nat['out_ct_conntrack'] = get_handler(condensed_json, 'OUTPUT', 'NAT_CONNTRACK')
         nat['deleted'] = ''
-        return nat
-
-    # check if NAT66 connection tracking helpers need to be set up - this has to
-    # be done only once
-    if not get_handler(condensed_json, 'PREROUTING', 'NAT_CONNTRACK'):
-        nat['helper_functions'] = 'add'
-
-        # Retrieve current table handler positions
-        nat['pre_ct_ignore'] = get_handler(condensed_json, 'PREROUTING', 'VYOS_CT_IGNORE')
-        nat['pre_ct_conntrack'] = get_handler(condensed_json, 'PREROUTING', 'VYOS_CT_PREROUTING_HOOK')
-        nat['out_ct_ignore'] = get_handler(condensed_json, 'OUTPUT', 'VYOS_CT_IGNORE')
-        nat['out_ct_conntrack'] = get_handler(condensed_json, 'OUTPUT', 'VYOS_CT_OUTPUT_HOOK')
-    else:
-        nat['helper_functions'] = 'has'
 
     return nat
 
@@ -94,10 +58,6 @@ def verify(nat):
         # no need to verify the CLI as NAT66 is going to be deactivated
         return None
 
-    if 'helper_functions' in nat and nat['helper_functions'] != 'has':
-        if not (nat['pre_ct_conntrack'] or nat['out_ct_conntrack']):
-            raise Exception('could not determine nftable ruleset handlers')
-
     if dict_search('source.rule', nat):
         for rule, config in dict_search('source.rule', nat).items():
             err_msg = f'Source NAT66 configuration error in rule {rule}:'
@@ -147,6 +107,7 @@ def apply(nat):
         return None
 
     cmd(f'nft -f {nftables_nat66_config}')
+    call_dependents()
 
     return None
 
diff --git a/src/conf_mode/system_flow-accounting.py b/src/conf_mode/system_flow-accounting.py
index f29fc94fb..206f513c8 100755
--- a/src/conf_mode/system_flow-accounting.py
+++ b/src/conf_mode/system_flow-accounting.py
@@ -38,7 +38,7 @@ uacctd_conf_path = '/run/pmacct/uacctd.conf'
 systemd_service = 'uacctd.service'
 systemd_override = f'/run/systemd/system/{systemd_service}.d/override.conf'
 nftables_nflog_table = 'raw'
-nftables_nflog_chain = 'VYOS_CT_PREROUTING_HOOK'
+nftables_nflog_chain = 'VYOS_PREROUTING_HOOK'
 egress_nftables_nflog_table = 'inet mangle'
 egress_nftables_nflog_chain = 'FORWARD'