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✏️ Editing: nftables.py

# -*- coding: utf-8 -*-
#
# Copyright (C) 2018 Red Hat, Inc.
#
# Authors:
# Eric Garver <e@erig.me>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
from __future__ import absolute_import

import copy
import json
import ipaddress

from firewall.core.logger import log
from firewall.functions import check_mac, getPortRange, normalizeIP6, \
                               check_single_address, check_address
from firewall.errors import FirewallError, UNKNOWN_ERROR, INVALID_RULE, \
                            INVALID_ICMPTYPE, INVALID_TYPE, INVALID_ENTRY, \
                            INVALID_PORT
from firewall.core.rich import Rich_Accept, Rich_Reject, Rich_Drop, Rich_Mark, \
                               Rich_Masquerade, Rich_ForwardPort, Rich_IcmpBlock
from nftables.nftables import Nftables

TABLE_NAME = "firewalld"
TABLE_NAME_POLICY = TABLE_NAME + "_" + "policy_drop"
POLICY_CHAIN_PREFIX = "policy_"

# Map iptables (table, chain) to hooks and priorities.
# These are well defined by NF_IP_PRI_* defines in netfilter.
#
# This is analogous to ipXtables.BUILT_IN_CHAINS, but we omit the chains that
# are only used for direct rules.
#
# Note: All hooks use their standard position + NFT_HOOK_OFFSET. This means
# iptables will have DROP precedence. It also means that even if iptables
# ACCEPTs a packet it may still be dropped later by firewalld's rules.
#
NFT_HOOK_OFFSET = 10
IPTABLES_TO_NFT_HOOK = {
    #"security": {
    #    "INPUT": ("input", 50 + NFT_HOOK_OFFSET),
    #    "OUTPUT": ("output", 50 + NFT_HOOK_OFFSET),
    #    "FORWARD": ("forward", 50 + NFT_HOOK_OFFSET),
    #},
    "raw": {
    #   "PREROUTING": ("prerouting", -300 + NFT_HOOK_OFFSET),
    #   "OUTPUT": ("output", -300 + NFT_HOOK_OFFSET),
    },
    "mangle": {
        "PREROUTING": ("prerouting", -150 + NFT_HOOK_OFFSET),
    #    "POSTROUTING": ("postrouting", -150 + NFT_HOOK_OFFSET),
    #    "INPUT": ("input", -150 + NFT_HOOK_OFFSET),
    #    "OUTPUT": ("output", -150 + NFT_HOOK_OFFSET),
    #    "FORWARD": ("forward", -150 + NFT_HOOK_OFFSET),
    },
    "nat": {
        "PREROUTING": ("prerouting", -100 + NFT_HOOK_OFFSET),
        "POSTROUTING": ("postrouting", 100 + NFT_HOOK_OFFSET),
    #    "INPUT": ("input", 100 + NFT_HOOK_OFFSET),
    #    "OUTPUT": ("output", -100 + NFT_HOOK_OFFSET),
    },
    "filter": {
        "PREROUTING": ("prerouting", 0 + NFT_HOOK_OFFSET),
        "INPUT": ("input", 0 + NFT_HOOK_OFFSET),
        "FORWARD": ("forward", 0 + NFT_HOOK_OFFSET),
        "OUTPUT": ("output", 0 + NFT_HOOK_OFFSET),
    },
}

def _icmp_types_fragments(protocol, type, code=None):
    fragments = [{"match": {"left": {"payload": {"protocol": protocol, "field": "type"}},
                            "op": "==",
                            "right": type}}]
    if code is not None:
        fragments.append({"match": {"left": {"payload": {"protocol": protocol, "field": "code"}},
                                    "op": "==",
                                    "right": code}})
    return fragments

# Most ICMP types are provided by nft, but for the codes we have to use numeric
# values.
#
ICMP_TYPES_FRAGMENTS = {
    "ipv4": {
        "communication-prohibited":     _icmp_types_fragments("icmp", "destination-unreachable", 13),
        "destination-unreachable":      _icmp_types_fragments("icmp", "destination-unreachable"),
        "echo-reply":                   _icmp_types_fragments("icmp", "echo-reply"),
        "echo-request":                 _icmp_types_fragments("icmp", "echo-request"),
        "fragmentation-needed":         _icmp_types_fragments("icmp", "destination-unreachable", 4),
        "host-precedence-violation":    _icmp_types_fragments("icmp", "destination-unreachable", 14),
        "host-prohibited":              _icmp_types_fragments("icmp", "destination-unreachable", 10),
        "host-redirect":                _icmp_types_fragments("icmp", "redirect", 1),
        "host-unknown":                 _icmp_types_fragments("icmp", "destination-unreachable", 7),
        "host-unreachable":             _icmp_types_fragments("icmp", "destination-unreachable", 1),
        "ip-header-bad":                _icmp_types_fragments("icmp", "parameter-problem", 1),
        "network-prohibited":           _icmp_types_fragments("icmp", "destination-unreachable", 8),
        "network-redirect":             _icmp_types_fragments("icmp", "redirect", 0),
        "network-unknown":              _icmp_types_fragments("icmp", "destination-unreachable", 6),
        "network-unreachable":          _icmp_types_fragments("icmp", "destination-unreachable", 0),
        "parameter-problem":            _icmp_types_fragments("icmp", "parameter-problem"),
        "port-unreachable":             _icmp_types_fragments("icmp", "destination-unreachable", 3),
        "precedence-cutoff":            _icmp_types_fragments("icmp", "destination-unreachable", 15),
        "protocol-unreachable":         _icmp_types_fragments("icmp", "destination-unreachable", 2),
        "redirect":                     _icmp_types_fragments("icmp", "redirect"),
        "required-option-missing":      _icmp_types_fragments("icmp", "parameter-problem", 1),
        "router-advertisement":         _icmp_types_fragments("icmp", "router-advertisement"),
        "router-solicitation":          _icmp_types_fragments("icmp", "router-solicitation"),
        "source-quench":                _icmp_types_fragments("icmp", "source-quench"),
        "source-route-failed":          _icmp_types_fragments("icmp", "destination-unreachable", 5),
        "time-exceeded":                _icmp_types_fragments("icmp", "time-exceeded"),
        "timestamp-reply":              _icmp_types_fragments("icmp", "timestamp-reply"),
        "timestamp-request":            _icmp_types_fragments("icmp", "timestamp-request"),
        "tos-host-redirect":            _icmp_types_fragments("icmp", "redirect", 3),
        "tos-host-unreachable":         _icmp_types_fragments("icmp", "destination-unreachable", 12),
        "tos-network-redirect":         _icmp_types_fragments("icmp", "redirect", 2),
        "tos-network-unreachable":      _icmp_types_fragments("icmp", "destination-unreachable", 11),
        "ttl-zero-during-reassembly":   _icmp_types_fragments("icmp", "time-exceeded", 1),
        "ttl-zero-during-transit":      _icmp_types_fragments("icmp", "time-exceeded", 0),
    },

"ipv6": {
        "address-unreachable":          _icmp_types_fragments("icmpv6", "destination-unreachable", 3),
        "bad-header":                   _icmp_types_fragments("icmpv6", "parameter-problem", 0),
        "beyond-scope":                 _icmp_types_fragments("icmpv6", "destination-unreachable", 2),
        "communication-prohibited":     _icmp_types_fragments("icmpv6", "destination-unreachable", 1),
        "destination-unreachable":      _icmp_types_fragments("icmpv6", "destination-unreachable"),
        "echo-reply":                   _icmp_types_fragments("icmpv6", "echo-reply"),
        "echo-request":                 _icmp_types_fragments("icmpv6", "echo-request"),
        "failed-policy":                _icmp_types_fragments("icmpv6", "destination-unreachable", 5),
        "mld-listener-done":            _icmp_types_fragments("icmpv6", "mld-listener-done"),
        "mld-listener-query":           _icmp_types_fragments("icmpv6", "mld-listener-query"),
        "mld-listener-report":          _icmp_types_fragments("icmpv6", "mld-listener-report"),
        "mld2-listener-report":         _icmp_types_fragments("icmpv6", "mld2-listener-report"),
        "neighbour-advertisement":      _icmp_types_fragments("icmpv6", "nd-neighbor-advert"),
        "neighbour-solicitation":       _icmp_types_fragments("icmpv6", "nd-neighbor-solicit"),
        "no-route":                     _icmp_types_fragments("icmpv6", "destination-unreachable", 0),
        "packet-too-big":               _icmp_types_fragments("icmpv6", "packet-too-big"),
        "parameter-problem":            _icmp_types_fragments("icmpv6", "parameter-problem"),
        "port-unreachable":             _icmp_types_fragments("icmpv6", "destination-unreachable", 4),
        "redirect":                     _icmp_types_fragments("icmpv6", "nd-redirect"),
        "reject-route":                 _icmp_types_fragments("icmpv6", "destination-unreachable", 6),
        "router-advertisement":         _icmp_types_fragments("icmpv6", "nd-router-advert"),
        "router-solicitation":          _icmp_types_fragments("icmpv6", "nd-router-solicit"),
        "time-exceeded":                _icmp_types_fragments("icmpv6", "time-exceeded"),
        "ttl-zero-during-reassembly":   _icmp_types_fragments("icmpv6", "time-exceeded", 1),
        "ttl-zero-during-transit":      _icmp_types_fragments("icmpv6", "time-exceeded", 0),
        "unknown-header-type":          _icmp_types_fragments("icmpv6", "parameter-problem", 1),
        "unknown-option":               _icmp_types_fragments("icmpv6", "parameter-problem", 2),
    }
}

class nftables(object):
    name = "nftables"
    policies_supported = True

def __init__(self, fw):
        self._fw = fw
        self.restore_command_exists = True
        self.available_tables = []
        self.rule_to_handle = {}
        self.rule_ref_count = {}
        self.rich_rule_priority_counts = {}
        self.policy_priority_counts = {}
        self.zone_source_index_cache = {}
        self.created_tables = {"inet": [], "ip": [], "ip6": []}

self.nftables = Nftables()
        self.nftables.set_echo_output(True)
        self.nftables.set_handle_output(True)

def _run_replace_zone_source(self, rule, zone_source_index_cache):
        for verb in ["add", "insert", "delete"]:
            if verb in rule:
                break

if "%%ZONE_SOURCE%%" in rule[verb]["rule"]:
            zone_source = (rule[verb]["rule"]["%%ZONE_SOURCE%%"]["zone"],
                           rule[verb]["rule"]["%%ZONE_SOURCE%%"]["address"])
            del rule[verb]["rule"]["%%ZONE_SOURCE%%"]
        elif "%%ZONE_INTERFACE%%" in rule[verb]["rule"]:
            zone_source = None
            del rule[verb]["rule"]["%%ZONE_INTERFACE%%"]
        else:
            return

family = rule[verb]["rule"]["family"]

if zone_source and verb == "delete":
            if family in zone_source_index_cache and \
               zone_source in zone_source_index_cache[family]:
                zone_source_index_cache[family].remove(zone_source)
        elif verb != "delete":
            if family not in zone_source_index_cache:
                zone_source_index_cache[family] = []

if zone_source:
                # order source based dispatch by zone name
                if zone_source not in zone_source_index_cache[family]:
                    zone_source_index_cache[family].append(zone_source)
                    zone_source_index_cache[family].sort(key=lambda x: x[0])

index = zone_source_index_cache[family].index(zone_source)
            else:
                if self._fw._allow_zone_drifting:
                    index = 0
                else:
                    index = len(zone_source_index_cache[family])

_verb_snippet = rule[verb]
            del rule[verb]
            if index == 0:
                rule["insert"] = _verb_snippet
            else:
                index -= 1 # point to the rule before insertion point
                rule["add"] = _verb_snippet
                rule["add"]["rule"]["index"] = index

def reverse_rule(self, dict):
        if "insert" in dict:
            return {"delete": copy.deepcopy(dict["insert"])}
        elif "add" in dict:
            return {"delete": copy.deepcopy(dict["add"])}
        else:
            raise FirewallError(UNKNOWN_ERROR, "Failed to reverse rule")

def _set_rule_replace_priority(self, rule, priority_counts, token):
        for verb in ["add", "insert", "delete"]:
            if verb in rule:
                break

if token in rule[verb]["rule"]:
            priority = rule[verb]["rule"][token]
            del rule[verb]["rule"][token]
            if type(priority) != int:
                raise FirewallError(INVALID_RULE, "priority must be followed by a number")
            chain = (rule[verb]["rule"]["family"], rule[verb]["rule"]["chain"]) # family, chain
            # Add the rule to the priority counts. We don't need to store the
            # rule, just bump the ref count for the priority value.
            if verb == "delete":
                if chain not in priority_counts or \
                   priority not in priority_counts[chain] or \
                   priority_counts[chain][priority] <= 0:
                    raise FirewallError(UNKNOWN_ERROR, "nonexistent or underflow of priority count")

priority_counts[chain][priority] -= 1
            else:
                if chain not in priority_counts:
                    priority_counts[chain] = {}
                if priority not in priority_counts[chain]:
                    priority_counts[chain][priority] = 0

# calculate index of new rule
                index = 0
                for p in sorted(priority_counts[chain].keys()):
                    if p == priority and verb == "insert":
                        break
                    index += priority_counts[chain][p]
                    if p == priority and verb == "add":
                        break

priority_counts[chain][priority] += 1

_verb_snippet = rule[verb]
                del rule[verb]
                if index == 0:
                    rule["insert"] = _verb_snippet
                else:
                    index -= 1 # point to the rule before insertion point
                    rule["add"] = _verb_snippet
                    rule["add"]["rule"]["index"] = index

def _get_rule_key(self, rule):
        for verb in ["add", "insert", "delete"]:
            if verb in rule and "rule" in rule[verb]:
                rule_key = copy.deepcopy(rule[verb]["rule"])
                for non_key in ["index", "handle", "position"]:
                    if non_key in rule_key:
                        del rule_key[non_key]
                # str(rule_key) is insufficient because dictionary order is
                # not stable.. so abuse the JSON library
                rule_key = json.dumps(rule_key, sort_keys=True)
                return rule_key
        # Not a rule (it's a table, chain, etc)
        return None

def set_rules(self, rules, log_denied):
        _valid_verbs = ["add", "insert", "delete", "flush", "replace"]
        _valid_add_verbs = ["add", "insert", "replace"]
        _deduplicated_rules = []
        _executed_rules = []
        rich_rule_priority_counts = copy.deepcopy(self.rich_rule_priority_counts)
        policy_priority_counts = copy.deepcopy(self.policy_priority_counts)
        zone_source_index_cache = copy.deepcopy(self.zone_source_index_cache)
        rule_ref_count = self.rule_ref_count.copy()
        for rule in rules:
            if type(rule) != dict:
                raise FirewallError(UNKNOWN_ERROR, "rule must be a dictionary, rule: %s" % (rule))

for verb in _valid_verbs:
                if verb in rule:
                    break
            if verb not in rule:
                raise FirewallError(INVALID_RULE, "no valid verb found, rule: %s" % (rule))

rule_key = self._get_rule_key(rule)

# rule deduplication
            if rule_key in rule_ref_count:
                log.debug2("%s: prev rule ref cnt %d, %s", self.__class__,
                           rule_ref_count[rule_key], rule_key)
                if verb != "delete":
                    rule_ref_count[rule_key] += 1
                    continue
                elif rule_ref_count[rule_key] > 1:
                    rule_ref_count[rule_key] -= 1
                    continue
                elif rule_ref_count[rule_key] == 1:
                    rule_ref_count[rule_key] -= 1
                else:
                    raise FirewallError(UNKNOWN_ERROR, "rule ref count bug: rule_key '%s', cnt %d"
                                                       % (rule_key, rule_ref_count[rule_key]))
            elif rule_key and verb != "delete":
                rule_ref_count[rule_key] = 1

_deduplicated_rules.append(rule)

_rule = copy.deepcopy(rule)
            if rule_key:
                # filter empty rule expressions. Rich rules add quite a bit of
                # them, but it makes the rest of the code simpler. libnftables
                # does not tolerate them.
                _rule[verb]["rule"]["expr"] = list(filter(None, _rule[verb]["rule"]["expr"]))

self._set_rule_replace_priority(_rule, rich_rule_priority_counts, "%%RICH_RULE_PRIORITY%%")
                self._set_rule_replace_priority(_rule, policy_priority_counts, "%%POLICY_PRIORITY%%")
                self._run_replace_zone_source(_rule, zone_source_index_cache)

# delete using rule handle
                if verb == "delete":
                    _rule = {"delete": {"rule": {"family": _rule["delete"]["rule"]["family"],
                                                 "table": _rule["delete"]["rule"]["table"],
                                                 "chain": _rule["delete"]["rule"]["chain"],
                                                 "handle": self.rule_to_handle[rule_key]}}}

_executed_rules.append(_rule)

json_blob = {"nftables": [{"metainfo": {"json_schema_version": 1}}] + _executed_rules}
        if log.getDebugLogLevel() >= 3:
            # guarded with if statement because json.dumps() is expensive.
            log.debug3("%s: calling python-nftables with JSON blob: %s", self.__class__,
                       json.dumps(json_blob))
        rc, output, error = self.nftables.json_cmd(json_blob)
        if rc != 0:
            raise ValueError("'%s' failed: %s\nJSON blob:\n%s" % ("python-nftables", error, json.dumps(json_blob)))

self.rich_rule_priority_counts = rich_rule_priority_counts
        self.policy_priority_counts = policy_priority_counts
        self.zone_source_index_cache = zone_source_index_cache
        self.rule_ref_count = rule_ref_count

index = 0
        for rule in _deduplicated_rules:
            index += 1 # +1 due to metainfo
            rule_key = self._get_rule_key(rule)

if not rule_key:
                continue

if "delete" in rule:
                del self.rule_to_handle[rule_key]
                del self.rule_ref_count[rule_key]
                continue

for verb in _valid_add_verbs:
                if verb in output["nftables"][index]:
                    break
            if verb not in output["nftables"][index]:
                continue

self.rule_to_handle[rule_key] = output["nftables"][index][verb]["rule"]["handle"]

def set_rule(self, rule, log_denied):
        self.set_rules([rule], log_denied)
        return ""

def get_available_tables(self, table=None):
        # Tables always exist in nftables
        return [table] if table else IPTABLES_TO_NFT_HOOK.keys()

def _build_delete_table_rules(self, table):
        # To avoid nftables returning ENOENT we always add the table before
        # deleting to guarantee it will exist.
        #
        # In the future, this add+delete should be replaced with "destroy", but
        # that verb is too new to rely upon.
        rules = []
        for family in ["inet", "ip", "ip6"]:
            rules.append({"add": {"table": {"family": family,
                                            "name": table}}})
            rules.append({"delete": {"table": {"family": family,
                                               "name": table}}})
        return rules

def build_flush_rules(self):
        # Policy is stashed in a separate table that we're _not_ going to
        # flush. As such, we retain the policy rule handles and ref counts.
        saved_rule_to_handle = {}
        saved_rule_ref_count = {}
        for rule in self._build_set_policy_rules_ct_rules(True):
            policy_key = self._get_rule_key(rule)
            if policy_key in self.rule_to_handle:
                saved_rule_to_handle[policy_key] = self.rule_to_handle[policy_key]
                saved_rule_ref_count[policy_key] = self.rule_ref_count[policy_key]

self.rule_to_handle = saved_rule_to_handle
        self.rule_ref_count = saved_rule_ref_count
        self.rich_rule_priority_counts = {}
        self.policy_priority_counts = {}
        self.zone_source_index_cache = {}

for family in ["inet", "ip", "ip6"]:
            if TABLE_NAME in self.created_tables[family]:
                self.created_tables[family].remove(TABLE_NAME)

return self._build_delete_table_rules(TABLE_NAME)

def _build_set_policy_rules_ct_rules(self, enable):
        add_del = { True: "add", False: "delete" }[enable]
        rules = []
        for hook in ["input", "forward", "output"]:
            rules.append({add_del: {"rule": {"family": "inet",
                                             "table": TABLE_NAME_POLICY,
                                             "chain": "%s_%s" % ("filter", hook),
                                             "expr": [{"match": {"left": {"ct": {"key": "state"}},
                                                                 "op": "in",
                                                                 "right": {"set": ["established", "related"]}}},
                                                      {"accept": None}]}}})
        return rules

def build_set_policy_rules(self, policy):
        # Policy is not exposed to the user. It's only to make sure we DROP
        # packets while reloading and for panic mode. As such, using hooks with
        # a higher priority than our base chains is sufficient.
        rules = []
        if policy == "PANIC":
            rules.append({"add": {"table": {"family": "inet",
                                            "name": TABLE_NAME_POLICY}}})
            self.created_tables["inet"].append(TABLE_NAME_POLICY)

# Use "raw" priority for panic mode. This occurs before
            # conntrack, mangle, nat, etc
            for hook in ["prerouting", "output"]:
                rules.append({"add": {"chain": {"family": "inet",
                                                "table": TABLE_NAME_POLICY,
                                                "name": "%s_%s" % ("raw", hook),
                                                "type": "filter",
                                                "hook": hook,
                                                "prio": -300 + NFT_HOOK_OFFSET - 1,
                                                "policy": "drop"}}})
        if policy == "DROP":
            rules.append({"add": {"table": {"family": "inet",
                                            "name": TABLE_NAME_POLICY}}})
            self.created_tables["inet"].append(TABLE_NAME_POLICY)

# To drop everything except existing connections we use
            # "filter" because it occurs _after_ conntrack.
            for hook in ["input", "forward", "output"]:
                rules.append({"add": {"chain": {"family": "inet",
                                                "table": TABLE_NAME_POLICY,
                                                "name": "%s_%s" % ("filter", hook),
                                                "type": "filter",
                                                "hook": hook,
                                                "prio": 0 + NFT_HOOK_OFFSET - 1,
                                                "policy": "drop"}}})

rules += self._build_set_policy_rules_ct_rules(True)
        elif policy == "ACCEPT":
            for rule in self._build_set_policy_rules_ct_rules(False):
                policy_key = self._get_rule_key(rule)
                if policy_key in self.rule_to_handle:
                    rules.append(rule)

rules += self._build_delete_table_rules(TABLE_NAME_POLICY)

if TABLE_NAME_POLICY in self.created_tables["inet"]:
                self.created_tables["inet"].remove(TABLE_NAME_POLICY)
        else:
            FirewallError(UNKNOWN_ERROR, "not implemented")

return rules

def supported_icmp_types(self, ipv=None):
        # nftables supports any icmp_type via arbitrary type/code matching.
        # We just need a translation for it in ICMP_TYPES_FRAGMENTS.
        supported = set()

for _ipv in [ipv] if ipv else ICMP_TYPES_FRAGMENTS.keys():
            supported.update(ICMP_TYPES_FRAGMENTS[_ipv].keys())

return list(supported)

def build_default_tables(self):
        default_tables = []
        for family in ["inet", "ip", "ip6"]:
            default_tables.append({"add": {"table": {"family": family,
                                                     "name": TABLE_NAME}}})
            self.created_tables[family].append(TABLE_NAME)
        return default_tables

def build_default_rules(self, log_denied="off"):
        default_rules = []
        for chain in IPTABLES_TO_NFT_HOOK["mangle"].keys():
            default_rules.append({"add": {"chain": {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "name": "mangle_%s" % chain,
                                                    "type": "filter",
                                                    "hook": "%s" % IPTABLES_TO_NFT_HOOK["mangle"][chain][0],
                                                    "prio": IPTABLES_TO_NFT_HOOK["mangle"][chain][1]}}})
            for dispatch_suffix in ["POLICIES_pre", "ZONES_SOURCE", "ZONES", "POLICIES_post"] if self._fw._allow_zone_drifting else ["POLICIES_pre", "ZONES", "POLICIES_post"]:
                default_rules.append({"add": {"chain": {"family": "inet",
                                                        "table": TABLE_NAME,
                                                        "name": "mangle_%s_%s" % (chain, dispatch_suffix)}}})
                default_rules.append({"add": {"rule":  {"family": "inet",
                                                        "table": TABLE_NAME,
                                                        "chain": "mangle_%s" % chain,
                                                        "expr": [{"jump": {"target": "mangle_%s_%s" % (chain, dispatch_suffix)}}]}}})

for family in ["ip", "ip6"]:
            for chain in IPTABLES_TO_NFT_HOOK["nat"].keys():
                default_rules.append({"add": {"chain": {"family": family,
                                                        "table": TABLE_NAME,
                                                        "name": "nat_%s" % chain,
                                                        "type": "nat",
                                                        "hook": "%s" % IPTABLES_TO_NFT_HOOK["nat"][chain][0],
                                                        "prio": IPTABLES_TO_NFT_HOOK["nat"][chain][1]}}})

for dispatch_suffix in ["POLICIES_pre", "ZONES_SOURCE", "ZONES", "POLICIES_post"] if self._fw._allow_zone_drifting else ["POLICIES_pre", "ZONES", "POLICIES_post"]:
                    default_rules.append({"add": {"chain": {"family": family,
                                                            "table": TABLE_NAME,
                                                            "name": "nat_%s_%s" % (chain, dispatch_suffix)}}})
                    default_rules.append({"add": {"rule":  {"family": family,
                                                            "table": TABLE_NAME,
                                                            "chain": "nat_%s" % chain,
                                                            "expr": [{"jump": {"target": "nat_%s_%s" % (chain, dispatch_suffix)}}]}}})

for chain in IPTABLES_TO_NFT_HOOK["filter"].keys():
            default_rules.append({"add": {"chain": {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "name": "filter_%s" % chain,
                                                    "type": "filter",
                                                    "hook": "%s" % IPTABLES_TO_NFT_HOOK["filter"][chain][0],
                                                    "prio": IPTABLES_TO_NFT_HOOK["filter"][chain][1]}}})

# filter, INPUT
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "INPUT",
                                                "expr": [{"match": {"left": {"ct": {"key": "state"}},
                                                                    "op": "in",
                                                                    "right": {"set": ["established", "related"]}}},
                                                         {"accept": None}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "INPUT",
                                                "expr": [{"match": {"left": {"ct": {"key": "status"}},
                                                                    "op": "in",
                                                                    "right": "dnat"}},
                                                         {"accept": None}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "INPUT",
                                                "expr": [{"match": {"left": {"meta": {"key": "iifname"}},
                                                                    "op": "==",
                                                                    "right": "lo"}},
                                                         {"accept": None}]}}})
        for dispatch_suffix in ["POLICIES_pre", "ZONES_SOURCE", "ZONES", "POLICIES_post"] if self._fw._allow_zone_drifting else ["POLICIES_pre", "ZONES", "POLICIES_post"]:
            default_rules.append({"add": {"chain": {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "name": "filter_%s_%s" % ("INPUT", dispatch_suffix)}}})
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "INPUT",
                                                    "expr": [{"jump": {"target": "filter_%s_%s" % ("INPUT", dispatch_suffix)}}]}}})
        if log_denied != "off":
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "INPUT",
                                                    "expr": [{"match": {"left": {"ct": {"key": "state"}},
                                                                        "op": "in",
                                                                        "right": {"set": ["invalid"]}}},
                                                             self._pkttype_match_fragment(log_denied),
                                                             {"log": {"prefix": "STATE_INVALID_DROP: "}}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "INPUT",
                                                "expr": [{"match": {"left": {"ct": {"key": "state"}},
                                                                    "op": "in",
                                                                    "right": {"set": ["invalid"]}}},
                                                         {"drop": None}]}}})
        if log_denied != "off":
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "INPUT",
                                                    "expr": [self._pkttype_match_fragment(log_denied),
                                                             {"log": {"prefix": "FINAL_REJECT: "}}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "INPUT",
                                                "expr": [{"reject": {"type": "icmpx", "expr": "admin-prohibited"}}]}}})

# filter, FORWARD
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "FORWARD",
                                                "expr": [{"match": {"left": {"ct": {"key": "state"}},
                                                                    "op": "in",
                                                                    "right": {"set": ["established", "related"]}}},
                                                         {"accept": None}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "FORWARD",
                                                "expr": [{"match": {"left": {"ct": {"key": "status"}},
                                                                    "op": "in",
                                                                    "right": "dnat"}},
                                                         {"accept": None}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "FORWARD",
                                                "expr": [{"match": {"left": {"meta": {"key": "iifname"}},
                                                                    "op": "==",
                                                                    "right": "lo"}},
                                                         {"accept": None}]}}})
        for dispatch_suffix in ["POLICIES_pre"]:
            default_rules.append({"add": {"chain": {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "name": "filter_%s_%s" % ("FORWARD", dispatch_suffix)}}})
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "FORWARD",
                                                    "expr": [{"jump": {"target": "filter_%s_%s" % ("FORWARD", dispatch_suffix)}}]}}})
        for direction in ["IN", "OUT"]:
            for dispatch_suffix in ["ZONES_SOURCE", "ZONES"] if self._fw._allow_zone_drifting else ["ZONES"]:
                default_rules.append({"add": {"chain": {"family": "inet",
                                                        "table": TABLE_NAME,
                                                        "name": "filter_%s_%s_%s" % ("FORWARD", direction, dispatch_suffix)}}})
                default_rules.append({"add": {"rule":  {"family": "inet",
                                                        "table": TABLE_NAME,
                                                        "chain": "filter_%s" % "FORWARD",
                                                        "expr": [{"jump": {"target": "filter_%s_%s_%s" % ("FORWARD", direction, dispatch_suffix)}}]}}})
        for dispatch_suffix in ["POLICIES_post"]:
            default_rules.append({"add": {"chain": {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "name": "filter_%s_%s" % ("FORWARD", dispatch_suffix)}}})
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "FORWARD",
                                                    "expr": [{"jump": {"target": "filter_%s_%s" % ("FORWARD", dispatch_suffix)}}]}}})
        if log_denied != "off":
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "FORWARD",
                                                    "expr": [{"match": {"left": {"ct": {"key": "state"}},
                                                                        "op": "in",
                                                                        "right": {"set": ["invalid"]}}},
                                                             self._pkttype_match_fragment(log_denied),
                                                             {"log": {"prefix": "STATE_INVALID_DROP: "}}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "FORWARD",
                                                "expr": [{"match": {"left": {"ct": {"key": "state"}},
                                                                    "op": "in",
                                                                    "right": {"set": ["invalid"]}}},
                                                         {"drop": None}]}}})
        if log_denied != "off":
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "FORWARD",
                                                    "expr": [self._pkttype_match_fragment(log_denied),
                                                             {"log": {"prefix": "FINAL_REJECT: "}}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "FORWARD",
                                                "expr": [{"reject": {"type": "icmpx", "expr": "admin-prohibited"}}]}}})

# filter, OUTPUT
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_%s" % "OUTPUT",
                                                "expr": [{"match": {"left": {"ct": {"key": "state"}},
                                                                    "op": "in",
                                                                    "right": {"set": ["established", "related"]}}},
                                                         {"accept": None}]}}})
        default_rules.append({"add": {"rule":  {"family": "inet",
                                                "table": TABLE_NAME,
                                                "chain": "filter_OUTPUT",
                                                "expr": [{"match": {"left": {"meta": {"key": "oifname"}},
                                                          "op": "==",
                                                          "right": "lo"}},
                                                         {"accept": None}]}}})
        for dispatch_suffix in ["POLICIES_pre"]:
            default_rules.append({"add": {"chain": {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "name": "filter_%s_%s" % ("OUTPUT", dispatch_suffix)}}})
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "OUTPUT",
                                                    "expr": [{"jump": {"target": "filter_%s_%s" % ("OUTPUT", dispatch_suffix)}}]}}})
        for dispatch_suffix in ["POLICIES_post"]:
            default_rules.append({"add": {"chain": {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "name": "filter_%s_%s" % ("OUTPUT", dispatch_suffix)}}})
            default_rules.append({"add": {"rule":  {"family": "inet",
                                                    "table": TABLE_NAME,
                                                    "chain": "filter_%s" % "OUTPUT",
                                                    "expr": [{"jump": {"target": "filter_%s_%s" % ("OUTPUT", dispatch_suffix)}}]}}})

return default_rules

def get_zone_table_chains(self, table):
        if table == "filter":
            return ["INPUT", "FORWARD_IN", "FORWARD_OUT"]
        if table == "mangle":
            return ["PREROUTING"]
        if table == "nat":
            return ["PREROUTING", "POSTROUTING"]

return []

def build_policy_ingress_egress_rules(self, enable, policy, table, chain,
                                          ingress_interfaces, egress_interfaces,
                                          ingress_sources, egress_sources,
                                          family="inet"):
        # nat tables need to use ip/ip6 family
        if table == "nat" and family == "inet":
            rules = []
            rules.extend(self.build_policy_ingress_egress_rules(enable, policy, table, chain,
                                          ingress_interfaces, egress_interfaces,
                                          ingress_sources, egress_sources,
                                          family="ip"))
            rules.extend(self.build_policy_ingress_egress_rules(enable, policy, table, chain,
                                          ingress_interfaces, egress_interfaces,
                                          ingress_sources, egress_sources,
                                          family="ip6"))
            return rules

p_obj = self._fw.policy.get_policy(policy)
        chain_suffix = "pre" if p_obj.priority < 0 else "post"
        isSNAT = True if (table == "nat" and chain == "POSTROUTING") else False
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX, isSNAT)

ingress_fragments = []
        egress_fragments = []
        if ingress_interfaces:
            ingress_fragments.append({"match": {"left": {"meta": {"key": "iifname"}},
                                                "op": "==",
                                                "right": {"set": list(ingress_interfaces)}}})
        if egress_interfaces:
            egress_fragments.append({"match": {"left": {"meta": {"key": "oifname"}},
                                               "op": "==",
                                               "right": {"set": list(egress_interfaces)}}})
        ipv_to_family = {"ipv4": "ip", "ipv6": "ip6"}
        if ingress_sources:
            for src in ingress_sources:
                # skip if this source doesn't apply to the current family.
                if table == "nat":
                    ipv = self._fw.zone.check_source(src)
                    if ipv in ipv_to_family and family != ipv_to_family[ipv]:
                        continue

ingress_fragments.append(self._rule_addr_fragment("saddr", src))
        if egress_sources:
            for dst in egress_sources:
                # skip if this source doesn't apply to the current family.
                if table == "nat":
                    ipv = self._fw.zone.check_source(dst)
                    if ipv in ipv_to_family and family != ipv_to_family[ipv]:
                        continue

egress_fragments.append(self._rule_addr_fragment("daddr", dst))

def _generate_policy_dispatch_rule(ingress_fragment, egress_fragment):
            expr_fragments = []
            if ingress_fragment:
                expr_fragments.append(ingress_fragment)
            if egress_fragment:
                expr_fragments.append(egress_fragment)
            expr_fragments.append({"jump": {"target": "%s_%s" % (table, _policy)}})

rule = {"family": family,
                    "table": TABLE_NAME,
                    "chain": "%s_%s_POLICIES_%s" % (table, chain, chain_suffix),
                    "expr": expr_fragments}
            rule.update(self._policy_priority_fragment(p_obj))

if enable:
                return {"add": {"rule": rule}}
            else:
                return {"delete": {"rule": rule}}

rules = []
        if ingress_fragments: # zone --> [zone, ANY, HOST]
            for ingress_fragment in ingress_fragments:
                if egress_fragments:
                    # zone --> zone
                    for egress_fragment in egress_fragments:
                        rules.append(_generate_policy_dispatch_rule(ingress_fragment, egress_fragment))
                elif table =="nat" and egress_sources:
                    # if the egress source is not for the current family (there
                    # are no egress fragments), then avoid creating an invalid
                    # catch all rule.
                    pass
                else:
                    # zone --> [ANY, HOST]
                    rules.append(_generate_policy_dispatch_rule(ingress_fragment, None))
        elif table =="nat" and ingress_sources:
            # if the ingress source is not for the current family (there are no
            # ingress fragments), then avoid creating an invalid catch all
            # rule.
            pass
        else: # [ANY, HOST] --> [zone, ANY, HOST]
            if egress_fragments:
                # [ANY, HOST] --> zone
                for egress_fragment in egress_fragments:
                    rules.append(_generate_policy_dispatch_rule(None, egress_fragment))
            elif table =="nat" and egress_sources:
                # if the egress source is not for the current family (there are
                # no egress fragments), then avoid creating an invalid catch
                # all rule.
                pass
            else:
                # [ANY, HOST] --> [ANY, HOST]
                rules.append(_generate_policy_dispatch_rule(None, None))

return rules

def build_zone_source_interface_rules(self, enable, zone, policy, interface,
                                          table, chain, append=False,
                                          family="inet"):
        # nat tables needs to use ip/ip6 family
        if table == "nat" and family == "inet":
            rules = []
            rules.extend(self.build_zone_source_interface_rules(enable, zone, policy,
                            interface, table, chain, append, "ip"))
            rules.extend(self.build_zone_source_interface_rules(enable, zone, policy,
                            interface, table, chain, append, "ip6"))
            return rules

isSNAT = True if (table == "nat" and chain == "POSTROUTING") else False
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX, isSNAT=isSNAT)
        opt = {
            "PREROUTING": "iifname",
            "POSTROUTING": "oifname",
            "INPUT": "iifname",
            "FORWARD_IN": "iifname",
            "FORWARD_OUT": "oifname",
            "OUTPUT": "oifname",
        }[chain]

if interface[len(interface)-1] == "+":
            interface = interface[:len(interface)-1] + "*"

action = "goto"

if interface == "*":
            expr_fragments = [{action: {"target": "%s_%s" % (table, _policy)}}]
        else:
            expr_fragments = [{"match": {"left": {"meta": {"key": opt}},
                                         "op": "==",
                                         "right": interface}},
                              {action: {"target": "%s_%s" % (table, _policy)}}]

if enable and not append:
            verb = "insert"
            rule = {"family": family,
                    "table": TABLE_NAME,
                    "chain": "%s_%s_ZONES" % (table, chain),
                    "expr": expr_fragments}
            rule.update(self._zone_interface_fragment())
        elif enable:
            verb = "add"
            rule = {"family": family,
                    "table": TABLE_NAME,
                    "chain": "%s_%s_ZONES" % (table, chain),
                    "expr": expr_fragments}
        else:
            verb = "delete"
            rule = {"family": family,
                    "table": TABLE_NAME,
                    "chain": "%s_%s_ZONES" % (table, chain),
                    "expr": expr_fragments}
            if not append:
                rule.update(self._zone_interface_fragment())

return [{verb: {"rule": rule}}]

def build_zone_source_address_rules(self, enable, zone, policy,
                                        address, table, chain, family="inet"):
        # nat tables needs to use ip/ip6 family
        if table == "nat" and family == "inet":
            rules = []
            if address.startswith("ipset:"):
                ipset_family = self._set_get_family(address[len("ipset:"):])
            else:
                ipset_family = None

if check_address("ipv4", address) or check_mac(address) or ipset_family == "ip":
                rules.extend(self.build_zone_source_address_rules(enable, zone, policy,
                                    address, table, chain, "ip"))
            if check_address("ipv6", address) or check_mac(address) or ipset_family == "ip6":
                rules.extend(self.build_zone_source_address_rules(enable, zone, policy,
                                    address, table, chain, "ip6"))
            return rules

opt = {
            "PREROUTING": "saddr",
            "POSTROUTING": "daddr",
            "INPUT": "saddr",
            "FORWARD_IN": "saddr",
            "FORWARD_OUT": "daddr",
            "OUTPUT": "daddr",
        }[chain]

if self._fw._allow_zone_drifting:
            zone_dispatch_chain = "%s_%s_ZONES_SOURCE" % (table, chain)
        else:
            zone_dispatch_chain = "%s_%s_ZONES" % (table, chain)

action = "goto"

rule = {"family": family,
                "table": TABLE_NAME,
                "chain": zone_dispatch_chain,
                "expr": [self._rule_addr_fragment(opt, address),
                         {action: {"target": "%s_%s" % (table, _policy)}}]}
        rule.update(self._zone_source_fragment(zone, address))
        return [{add_del: {"rule": rule}}]

def build_policy_chain_rules(self, enable, policy, table, chain, family="inet"):
        # nat tables needs to use ip/ip6 family
        if table == "nat" and family == "inet":
            rules = []
            rules.extend(self.build_policy_chain_rules(enable, policy, table, chain, "ip"))
            rules.extend(self.build_policy_chain_rules(enable, policy, table, chain, "ip6"))
            return rules

add_del = { True: "add", False: "delete" }[enable]
        isSNAT = True if (table == "nat" and chain == "POSTROUTING") else False
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX, isSNAT=isSNAT)

rules = []
        rules.append({add_del: {"chain": {"family": family,
                                          "table": TABLE_NAME,
                                          "name": "%s_%s" % (table, _policy)}}})
        for chain_suffix in ["pre", "log", "deny", "allow", "post"]:
            rules.append({add_del: {"chain": {"family": family,
                                              "table": TABLE_NAME,
                                              "name": "%s_%s_%s" % (table, _policy, chain_suffix)}}})

for chain_suffix in ["pre", "log", "deny", "allow", "post"]:
            rules.append({add_del: {"rule": {"family": family,
                                             "table": TABLE_NAME,
                                             "chain": "%s_%s" % (table, _policy),
                                             "expr": [{"jump": {"target": "%s_%s_%s" % (table, _policy, chain_suffix)}}]}}})

target = self._fw.policy._policies[policy].target

if self._fw.get_log_denied() != "off":
            if table == "filter":
                if target in ["REJECT", "%%REJECT%%", "DROP"]:
                    log_suffix = target
                    if target == "%%REJECT%%":
                        log_suffix = "REJECT"
                    rules.append({add_del: {"rule": {"family": family,
                                                     "table": TABLE_NAME,
                                                     "chain": "%s_%s" % (table, _policy),
                                                     "expr": [self._pkttype_match_fragment(self._fw.get_log_denied()),
                                                              {"log": {"prefix": "\"filter_%s_%s: \"" % (_policy, log_suffix)}}]}}})

if table == "filter" and \
           target in ["ACCEPT", "REJECT", "%%REJECT%%", "DROP"]:
            if target in ["%%REJECT%%", "REJECT"]:
                target_fragment = self._reject_fragment()
            else:
                target_fragment = {target.lower(): None}
            rules.append({add_del: {"rule": {"family": family,
                                             "table": TABLE_NAME,
                                             "chain": "%s_%s" % (table, _policy),
                                             "expr": [target_fragment]}}})

if not enable:
            rules.reverse()

return rules

def _pkttype_match_fragment(self, pkttype):
        if pkttype == "all":
            return {}
        elif pkttype in ["unicast", "broadcast", "multicast"]:
            return {"match": {"left": {"meta": {"key": "pkttype"}},
                               "op": "==",
                               "right": pkttype}}

raise FirewallError(INVALID_RULE, "Invalid pkttype \"%s\"", pkttype)

def _reject_types_fragment(self, reject_type):
        frags = {
            # REJECT_TYPES              : <nft reject rule fragment>
            "icmp-host-prohibited"      : {"reject": {"type": "icmp", "expr": "host-prohibited"}},
            "host-prohib"               : {"reject": {"type": "icmp", "expr": "host-prohibited"}},
            "icmp-net-prohibited"       : {"reject": {"type": "icmp", "expr": "net-prohibited"}},
            "net-prohib"                : {"reject": {"type": "icmp", "expr": "net-prohibited"}},
            "icmp-admin-prohibited"     : {"reject": {"type": "icmp", "expr": "admin-prohibited"}},
            "admin-prohib"              : {"reject": {"type": "icmp", "expr": "admin-prohibited"}},
            "icmp6-adm-prohibited"      : {"reject": {"type": "icmpv6", "expr": "admin-prohibited"}},
            "adm-prohibited"            : {"reject": {"type": "icmpv6", "expr": "admin-prohibited"}},

"icmp-net-unreachable"      : {"reject": {"type": "icmp", "expr": "net-unreachable"}},
            "net-unreach"               : {"reject": {"type": "icmp", "expr": "net-unreachable"}},
            "icmp-host-unreachable"     : {"reject": {"type": "icmp", "expr": "host-unreachable"}},
            "host-unreach"              : {"reject": {"type": "icmp", "expr": "host-unreachable"}},
            "icmp-port-unreachable"     : {"reject": {"type": "icmp", "expr": "port-unreachable"}},
            "icmp6-port-unreachable"    : {"reject": {"type": "icmpv6", "expr": "port-unreachable"}},
            "port-unreach"              : {"reject": {"type": "icmpx", "expr": "port-unreachable"}},
            "icmp-proto-unreachable"    : {"reject": {"type": "icmp", "expr": "prot-unreachable"}},
            "proto-unreach"             : {"reject": {"type": "icmp", "expr": "prot-unreachable"}},
            "icmp6-addr-unreachable"    : {"reject": {"type": "icmpv6", "expr": "addr-unreachable"}},
            "addr-unreach"              : {"reject": {"type": "icmpv6", "expr": "addr-unreachable"}},

"icmp6-no-route"            : {"reject": {"type": "icmpv6", "expr": "no-route"}},
            "no-route"                  : {"reject": {"type": "icmpv6", "expr": "no-route"}},

"tcp-reset"                 : {"reject": {"type": "tcp reset"}},
            "tcp-rst"                   : {"reject": {"type": "tcp reset"}},
        }
        return frags[reject_type]

def _reject_fragment(self):
        return {"reject": {"type": "icmpx",
                           "expr": "admin-prohibited"}}

def _icmp_match_fragment(self):
        return {"match": {"left": {"meta": {"key": "l4proto"}},
                          "op": "==",
                          "right": {"set": ["icmp", "icmpv6"]}}}

def _rich_rule_limit_fragment(self, limit):
        if not limit:
            return {}

rich_to_nft = {
            "s" : "second",
            "m" : "minute",
            "h" : "hour",
            "d" : "day",
        }

rate, duration = limit.value_parse()

d = {
            "rate": rate,
            "per": rich_to_nft[duration],
        }

burst = limit.burst_parse()
        if burst is not None:
            d["burst"] = burst

return {"limit": d}

def _rich_rule_chain_suffix(self, rich_rule):
        if type(rich_rule.element) in [Rich_Masquerade, Rich_ForwardPort, Rich_IcmpBlock]:
            # These are special and don't have an explicit action
            pass
        elif rich_rule.action:
            if type(rich_rule.action) not in [Rich_Accept, Rich_Reject, Rich_Drop, Rich_Mark]:
                raise FirewallError(INVALID_RULE, "Unknown action %s" % type(rich_rule.action))
        else:
            raise FirewallError(INVALID_RULE, "No rule action specified.")

if rich_rule.priority == 0:
            if type(rich_rule.element) in [Rich_Masquerade, Rich_ForwardPort] or \
               type(rich_rule.action) in [Rich_Accept, Rich_Mark]:
                return "allow"
            elif type(rich_rule.element) in [Rich_IcmpBlock] or \
                 type(rich_rule.action) in [Rich_Reject, Rich_Drop]:
                return "deny"
        elif rich_rule.priority < 0:
            return "pre"
        else:
            return "post"

def _rich_rule_chain_suffix_from_log(self, rich_rule):
        if not rich_rule.log and not rich_rule.audit:
            raise FirewallError(INVALID_RULE, "Not log or audit")

if rich_rule.priority == 0:
            return "log"
        elif rich_rule.priority < 0:
            return "pre"
        else:
            return "post"

def _zone_interface_fragment(self):
        return {"%%ZONE_INTERFACE%%": None}

def _zone_source_fragment(self, zone, address):
        if check_single_address("ipv6", address):
            address = normalizeIP6(address)
        elif check_address("ipv6", address):
            addr_split = address.split("/")
            address = normalizeIP6(addr_split[0]) + "/" + addr_split[1]
        return {"%%ZONE_SOURCE%%": {"zone": zone, "address": address}}

def _policy_priority_fragment(self, policy):
        return {"%%POLICY_PRIORITY%%": policy.priority}

def _rich_rule_priority_fragment(self, rich_rule):
        if not rich_rule or rich_rule.priority == 0:
            return {}
        return {"%%RICH_RULE_PRIORITY%%": rich_rule.priority}

def _rich_rule_log(self, policy, rich_rule, enable, table, expr_fragments):
        if not rich_rule.log:
            return {}

_policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)

add_del = { True: "add", False: "delete" }[enable]

chain_suffix = self._rich_rule_chain_suffix_from_log(rich_rule)

log_options = {}
        if rich_rule.log.prefix:
            log_options["prefix"] = "%s" % rich_rule.log.prefix
        if rich_rule.log.level:
            level = "warn" if "warning" == rich_rule.log.level else rich_rule.log.level
            log_options["level"] = "%s" % level

rule = {"family": "inet",
                "table": TABLE_NAME,
                "chain": "%s_%s_%s" % (table, _policy, chain_suffix),
                "expr": expr_fragments +
                        [self._rich_rule_limit_fragment(rich_rule.log.limit),
                         {"log": log_options}]}
        rule.update(self._rich_rule_priority_fragment(rich_rule))
        return {add_del: {"rule": rule}}

def _rich_rule_audit(self, policy, rich_rule, enable, table, expr_fragments):
        if not rich_rule.audit:
            return {}

_policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)

add_del = { True: "add", False: "delete" }[enable]

chain_suffix = self._rich_rule_chain_suffix_from_log(rich_rule)
        rule = {"family": "inet",
                "table": TABLE_NAME,
                "chain": "%s_%s_%s" % (table, _policy, chain_suffix),
                "expr": expr_fragments +
                        [self._rich_rule_limit_fragment(rich_rule.audit.limit),
                         {"log": {"level": "audit"}}]}
        rule.update(self._rich_rule_priority_fragment(rich_rule))
        return {add_del: {"rule": rule}}

def _rich_rule_action(self, policy, rich_rule, enable, table, expr_fragments):
        if not rich_rule.action:
            return {}

_policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)

add_del = { True: "add", False: "delete" }[enable]

chain_suffix = self._rich_rule_chain_suffix(rich_rule)
        chain = "%s_%s_%s" % (table, _policy, chain_suffix)
        if type(rich_rule.action) == Rich_Accept:
            rule_action = {"accept": None}
        elif type(rich_rule.action) == Rich_Reject:
            if rich_rule.action.type:
                rule_action = self._reject_types_fragment(rich_rule.action.type)
            else:
                rule_action = {"reject": None}
        elif type(rich_rule.action) ==  Rich_Drop:
            rule_action = {"drop": None}
        elif type(rich_rule.action) == Rich_Mark:
            table = "mangle"
            _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)
            chain = "%s_%s_%s" % (table, _policy, chain_suffix)
            value = rich_rule.action.set.split("/")
            if len(value) > 1:
                rule_action = {"mangle": {"key": {"meta": {"key": "mark"}},
                                          "value": {"^": [{"&": [{"meta": {"key": "mark"}}, value[1]]}, value[0]]}}}
            else:
                rule_action = {"mangle": {"key": {"meta": {"key": "mark"}},
                                          "value": value[0]}}

else:
            raise FirewallError(INVALID_RULE,
                                "Unknown action %s" % type(rich_rule.action))

rule = {"family": "inet",
                "table": TABLE_NAME,
                "chain": chain,
                "expr": expr_fragments +
                        [self._rich_rule_limit_fragment(rich_rule.action.limit), rule_action]}
        rule.update(self._rich_rule_priority_fragment(rich_rule))
        return {add_del: {"rule": rule}}

def _rule_addr_fragment(self, addr_field, address, invert=False):
        if address.startswith("ipset:"):
            return self._set_match_fragment(address[len("ipset:"):], True if "daddr" == addr_field else False, invert)
        else:
            if check_mac(address):
                family = "ether"
            elif check_single_address("ipv4", address):
                family = "ip"
            elif check_address("ipv4", address):
                family = "ip"
                normalized_address = ipaddress.IPv4Network(address, strict=False)
                address = {"prefix": {"addr": normalized_address.network_address.compressed, "len": normalized_address.prefixlen}}
            elif check_single_address("ipv6", address):
                family = "ip6"
                address = normalizeIP6(address)
            else:
                family = "ip6"
                addr_len = address.split("/")
                address = {"prefix": {"addr": normalizeIP6(addr_len[0]), "len": int(addr_len[1])}}

return {"match": {"left": {"payload": {"protocol": family,
                                                   "field": addr_field}},
                              "op": "!=" if invert else "==",
                              "right": address}}

def _rich_rule_family_fragment(self, rich_family):
        if not rich_family:
            return {}
        if rich_family not in ["ipv4", "ipv6"]:
            raise FirewallError(INVALID_RULE,
                                "Invalid family" % rich_family)

return {"match": {"left": {"meta": {"key": "nfproto"}},
                          "op": "==",
                          "right": rich_family}}

def _rich_rule_destination_fragment(self, rich_dest):
        if not rich_dest:
            return {}
        if rich_dest.addr:
            address = rich_dest.addr
        elif rich_dest.ipset:
            address = "ipset:" + rich_dest.ipset

return self._rule_addr_fragment("daddr", address, invert=rich_dest.invert)

def _rich_rule_source_fragment(self, rich_source):
        if not rich_source:
            return {}

if rich_source.addr:
            address = rich_source.addr
        elif hasattr(rich_source, "mac") and rich_source.mac:
            address = rich_source.mac
        elif hasattr(rich_source, "ipset") and rich_source.ipset:
            address = "ipset:" + rich_source.ipset

return self._rule_addr_fragment("saddr", address, invert=rich_source.invert)

def _port_fragment(self, port):
        range = getPortRange(port)
        if isinstance(range, int) and range < 0:
            raise FirewallError(INVALID_PORT)
        elif len(range) == 1:
            return range[0]
        else:
            return {"range": [range[0], range[1]]}

def build_policy_ports_rules(self, enable, policy, proto, port, destination=None, rich_rule=None):
        add_del = { True: "add", False: "delete" }[enable]
        table = "filter"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)

expr_fragments = []
        if rich_rule:
            expr_fragments.append(self._rich_rule_family_fragment(rich_rule.family))
        if destination:
            expr_fragments.append(self._rule_addr_fragment("daddr", destination))
        if rich_rule:
            expr_fragments.append(self._rich_rule_destination_fragment(rich_rule.destination))
            expr_fragments.append(self._rich_rule_source_fragment(rich_rule.source))

expr_fragments.append({"match": {"left": {"payload": {"protocol": proto,
                                                              "field": "dport"}},
                                         "op": "==",
                                         "right": self._port_fragment(port)}})
        if not rich_rule or type(rich_rule.action) != Rich_Mark:
            expr_fragments.append({"match": {"left": {"ct": {"key": "state"}},
                                             "op": "in",
                                             "right": {"set": ["new", "untracked"]}}})

rules = []
        if rich_rule:
            rules.append(self._rich_rule_log(policy, rich_rule, enable, table, expr_fragments))
            rules.append(self._rich_rule_audit(policy, rich_rule, enable, table, expr_fragments))
            rules.append(self._rich_rule_action(policy, rich_rule, enable, table, expr_fragments))
        else:
            rules.append({add_del: {"rule": {"family": "inet",
                                             "table": TABLE_NAME,
                                             "chain": "%s_%s_allow" % (table, _policy),
                                             "expr": expr_fragments + [{"accept": None}]}}})

return rules

def build_policy_protocol_rules(self, enable, policy, protocol, destination=None, rich_rule=None):
        add_del = { True: "add", False: "delete" }[enable]
        table = "filter"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)

expr_fragments.append({"match": {"left": {"meta": {"key": "l4proto"}},
                                         "op": "==",
                                         "right": protocol}})
        if not rich_rule or type(rich_rule.action) != Rich_Mark:
            expr_fragments.append({"match": {"left": {"ct": {"key": "state"}},
                                             "op": "in",
                                             "right": {"set": ["new", "untracked"]}}})

return rules

def build_policy_source_ports_rules(self, enable, policy, proto, port,
                                      destination=None, rich_rule=None):
        add_del = { True: "add", False: "delete" }[enable]
        table = "filter"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)

expr_fragments.append({"match": {"left": {"payload": {"protocol": proto,
                                                              "field": "sport"}},
                                         "op": "==",
                                         "right": self._port_fragment(port)}})
        if not rich_rule or type(rich_rule.action) != Rich_Mark:
            expr_fragments.append({"match": {"left": {"ct": {"key": "state"}},
                                             "op": "in",
                                             "right": {"set": ["new", "untracked"]}}})

return rules

def build_policy_helper_ports_rules(self, enable, policy, proto, port,
                                        destination, helper_name, module_short_name):
        table = "filter"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)
        add_del = { True: "add", False: "delete" }[enable]
        rules = []

if enable:
            rules.append({"add": {"ct helper": {"family": "inet",
                                                "table": TABLE_NAME,
                                                "name": "helper-%s-%s" % (helper_name, proto),
                                                "type": module_short_name,
                                                "protocol": proto}}})

expr_fragments = []
        if destination:
            expr_fragments.append(self._rule_addr_fragment("daddr", destination))
        expr_fragments.append({"match": {"left": {"payload": {"protocol": proto,
                                                              "field": "dport"}},
                                         "op": "==",
                                         "right": self._port_fragment(port)}})
        expr_fragments.append({"ct helper": "helper-%s-%s" % (helper_name, proto)})
        rules.append({add_del: {"rule": {"family": "inet",
                                         "table": TABLE_NAME,
                                         "chain": "filter_%s_allow" % (_policy),
                                         "expr": expr_fragments}}})

return rules

def build_zone_forward_rules(self, enable, zone, policy, table, interface=None, source=None):
        add_del = { True: "add", False: "delete" }[enable]
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)

rules = []

if interface:
            if interface[len(interface)-1] == "+":
                interface = interface[:len(interface)-1] + "*"

expr = [{"match": {"left": {"meta": {"key": "oifname"}},
                               "op": "==",
                               "right": interface}},
                    {"accept": None}]
        else: # source
            expr = [self._rule_addr_fragment("daddr", source), {"accept": None}]

rule = {"family": "inet",
                "table": TABLE_NAME,
                "chain": "filter_%s_allow" % (_policy),
                "expr": expr}
        rules.append({add_del: {"rule": rule}})

return rules

def _build_policy_masquerade_nat_rules(self, enable, policy, family, rich_rule=None):
        table = "nat"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX, isSNAT=True)

add_del = { True: "add", False: "delete" }[enable]

expr_fragments = []
        if rich_rule:
            expr_fragments.append(self._rich_rule_destination_fragment(rich_rule.destination))
            expr_fragments.append(self._rich_rule_source_fragment(rich_rule.source))
            chain_suffix = self._rich_rule_chain_suffix(rich_rule)
        else:
            chain_suffix = "allow"

rule = {"family": family,
                "table": TABLE_NAME,
                "chain": "nat_%s_%s" % (_policy, chain_suffix),
                "expr": expr_fragments +
                        [{"match": {"left": {"meta": {"key": "oifname"}},
                                    "op": "!=",
                                    "right": "lo"}},
                         {"masquerade": None}]}
        rule.update(self._rich_rule_priority_fragment(rich_rule))
        return [{add_del: {"rule": rule}}]

def build_policy_masquerade_rules(self, enable, policy, rich_rule=None):
        # nat tables needs to use ip/ip6 family
        rules = []
        if rich_rule and (rich_rule.family and rich_rule.family == "ipv6"
           or rich_rule.source and check_address("ipv6", rich_rule.source.addr)):
            rules.extend(self._build_policy_masquerade_nat_rules(enable, policy, "ip6", rich_rule))
        elif rich_rule and (rich_rule.family and rich_rule.family == "ipv4"
           or rich_rule.source and check_address("ipv4", rich_rule.source.addr)):
            rules.extend(self._build_policy_masquerade_nat_rules(enable, policy, "ip", rich_rule))
        else:
            rules.extend(self._build_policy_masquerade_nat_rules(enable, policy, "ip", rich_rule))

table = "filter"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)
        add_del = { True: "add", False: "delete" }[enable]

rule = {"family": "inet",
                "table": TABLE_NAME,
                "chain": "filter_%s_%s" % (_policy, chain_suffix),
                "expr": expr_fragments +
                        [{"match": {"left": {"ct": {"key": "state"}},
                                    "op": "in",
                                    "right": {"set": ["new", "untracked"]}}},
                         {"accept": None}]}
        rule.update(self._rich_rule_priority_fragment(rich_rule))
        rules.append({add_del: {"rule": rule}})

return rules

def _build_policy_forward_port_nat_rules(self, enable, policy, port, protocol,
                                           toaddr, toport, family,
                                           rich_rule=None):
        table = "nat"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)
        add_del = { True: "add", False: "delete" }[enable]

expr_fragments.append({"match": {"left": {"payload": {"protocol": protocol,
                                                              "field": "dport"}},
                                         "op": "==",
                                         "right": self._port_fragment(port)}})

if toaddr:
            if check_single_address("ipv6", toaddr):
                toaddr = normalizeIP6(toaddr)
            if toport and toport != "":
                expr_fragments.append({"dnat": {"addr": toaddr, "port": self._port_fragment(toport)}})
            else:
                expr_fragments.append({"dnat": {"addr": toaddr}})
        else:
            expr_fragments.append({"redirect": {"port": self._port_fragment(toport)}})

rule = {"family": family,
                "table": TABLE_NAME,
                "chain": "nat_%s_%s" % (_policy, chain_suffix),
                "expr": expr_fragments}
        rule.update(self._rich_rule_priority_fragment(rich_rule))
        return [{add_del: {"rule": rule}}]

def build_policy_forward_port_rules(self, enable, policy, port,
                                      protocol, toport, toaddr, rich_rule=None):
        rules = []
        if rich_rule and (rich_rule.family and rich_rule.family == "ipv6"
           or toaddr and check_single_address("ipv6", toaddr)):
            rules.extend(self._build_policy_forward_port_nat_rules(enable, policy,
                                port, protocol, toaddr, toport, "ip6", rich_rule))
        elif rich_rule and (rich_rule.family and rich_rule.family == "ipv4"
           or toaddr and check_single_address("ipv4", toaddr)):
            rules.extend(self._build_policy_forward_port_nat_rules(enable, policy,
                                port, protocol, toaddr, toport, "ip", rich_rule))
        else:
            if toaddr and check_single_address("ipv6", toaddr):
                rules.extend(self._build_policy_forward_port_nat_rules(enable, policy,
                                    port, protocol, toaddr, toport, "ip6", rich_rule))
            else:
                rules.extend(self._build_policy_forward_port_nat_rules(enable, policy,
                                    port, protocol, toaddr, toport, "ip", rich_rule))

return rules

def _icmp_types_to_nft_fragments(self, ipv, icmp_type):
        if icmp_type in ICMP_TYPES_FRAGMENTS[ipv]:
            return ICMP_TYPES_FRAGMENTS[ipv][icmp_type]
        else:
            raise FirewallError(INVALID_ICMPTYPE,
                                "ICMP type '%s' not supported by %s for %s" % (icmp_type, self.name, ipv))

def build_policy_icmp_block_rules(self, enable, policy, ict, rich_rule=None):
        table = "filter"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)
        add_del = { True: "add", False: "delete" }[enable]

if rich_rule and rich_rule.ipvs:
            ipvs = rich_rule.ipvs
        elif ict.destination:
            ipvs = []
            if "ipv4" in ict.destination:
                ipvs.append("ipv4")
            if "ipv6" in ict.destination:
                ipvs.append("ipv6")
        else:
            ipvs = ["ipv4", "ipv6"]

rules = []
        for ipv in ipvs:
            if self._fw.policy.query_icmp_block_inversion(policy):
                final_chain = "%s_%s_allow" % (table, _policy)
                target_fragment = {"accept": None}
            else:
                final_chain = "%s_%s_deny" % (table, _policy)
                target_fragment = self._reject_fragment()

expr_fragments = []
            if rich_rule:
                expr_fragments.append(self._rich_rule_family_fragment(rich_rule.family))
                expr_fragments.append(self._rich_rule_destination_fragment(rich_rule.destination))
                expr_fragments.append(self._rich_rule_source_fragment(rich_rule.source))
            expr_fragments.extend(self._icmp_types_to_nft_fragments(ipv, ict.name))

if rich_rule:
                rules.append(self._rich_rule_log(policy, rich_rule, enable, table, expr_fragments))
                rules.append(self._rich_rule_audit(policy, rich_rule, enable, table, expr_fragments))
                if rich_rule.action:
                    rules.append(self._rich_rule_action(policy, rich_rule, enable, table, expr_fragments))
                else:
                    chain_suffix = self._rich_rule_chain_suffix(rich_rule)
                    rule = {"family": "inet",
                            "table": TABLE_NAME,
                            "chain": "%s_%s_%s" % (table, _policy, chain_suffix),
                            "expr": expr_fragments + [self._reject_fragment()]}
                    rule.update(self._rich_rule_priority_fragment(rich_rule))
                    rules.append({add_del: {"rule": rule}})
            else:
                if self._fw.get_log_denied() != "off" and not self._fw.policy.query_icmp_block_inversion(policy):
                    rules.append({add_del: {"rule": {"family": "inet",
                                                     "table": TABLE_NAME,
                                                     "chain": final_chain,
                                                     "expr": (expr_fragments +
                                                              [self._pkttype_match_fragment(self._fw.get_log_denied()),
                                                               {"log": {"prefix": "\"%s_%s_ICMP_BLOCK: \"" % (table, policy)}}])}}})
                rules.append({add_del: {"rule": {"family": "inet",
                                                 "table": TABLE_NAME,
                                                 "chain": final_chain,
                                                 "expr": expr_fragments + [target_fragment]}}})

return rules

def build_policy_icmp_block_inversion_rules(self, enable, policy):
        table = "filter"
        _policy = self._fw.policy.policy_base_chain_name(policy, table, POLICY_CHAIN_PREFIX)
        rules = []
        add_del = { True: "add", False: "delete" }[enable]

if self._fw.policy.query_icmp_block_inversion(policy):
            target_fragment = self._reject_fragment()
        else:
            target_fragment = {"accept": None}

# WARN: The "index" used here must be kept in sync with
        # build_policy_chain_rules()
        #
        rules.append({add_del: {"rule": {"family": "inet",
                                         "table": TABLE_NAME,
                                         "chain": "%s_%s" % (table, _policy),
                                         "index": 4,
                                         "expr": [self._icmp_match_fragment(),
                                                  target_fragment]}}})

if self._fw.get_log_denied() != "off" and self._fw.policy.query_icmp_block_inversion(policy):
            rules.append({add_del: {"rule": {"family": "inet",
                                             "table": TABLE_NAME,
                                             "chain": "%s_%s" % (table, _policy),
                                             "index": 4,
                                             "expr": [self._icmp_match_fragment(),
                                                      self._pkttype_match_fragment(self._fw.get_log_denied()),
                                                      {"log": {"prefix": "%s_%s_ICMP_BLOCK: " % (table, policy)}}]}}})
        return rules

def build_rpfilter_rules(self, log_denied=False):
        rules = []
        expr_fragments = [{"match": {"left": {"meta": {"key": "nfproto"}},
                                     "op": "==",
                                     "right": "ipv6"}},
                          {"match": {"left": {"fib": {"flags": ["saddr", "iif", "mark"],
                                                      "result": "oif"}},
                                     "op": "==",
                                     "right": False}}]
        if log_denied != "off":
            expr_fragments.append({"log": {"prefix": "rpfilter_DROP: "}})
        expr_fragments.append({"drop": None})

rules.append({"insert": {"rule": {"family": "inet",
                                          "table": TABLE_NAME,
                                          "chain": "filter_PREROUTING",
                                          "expr": expr_fragments}}})
        # RHBZ#1058505, RHBZ#1575431 (bug in kernel 4.16-4.17)
        rules.append({"insert": {"rule": {"family": "inet",
                                          "table": TABLE_NAME,
                                          "chain": "filter_PREROUTING",
                                          "expr": [{"match": {"left": {"payload": {"protocol": "icmpv6",
                                                                                   "field": "type"}},
                                                              "op": "==",
                                                              "right": {"set": ["nd-router-advert", "nd-neighbor-solicit"]}}},
                                                   {"accept": None}]}}})
        return rules

def build_rfc3964_ipv4_rules(self):
        daddr_set = ["::0.0.0.0/96", # IPv4 compatible
                     "::ffff:0.0.0.0/96", # IPv4 mapped
                     "2002:0000::/24", # 0.0.0.0/8 (the system has no address assigned yet)
                     "2002:0a00::/24", # 10.0.0.0/8 (private)
                     "2002:7f00::/24", # 127.0.0.0/8 (loopback)
                     "2002:ac10::/28", # 172.16.0.0/12 (private)
                     "2002:c0a8::/32", # 192.168.0.0/16 (private)
                     "2002:a9fe::/32", # 169.254.0.0/16 (IANA Assigned DHCP link-local)
                     "2002:e000::/19", # 224.0.0.0/4 (multicast), 240.0.0.0/4 (reserved and broadcast)
                     ]
        daddr_set = [{"prefix": {"addr": x.split("/")[0], "len": int(x.split("/")[1])}} for x in daddr_set]

expr_fragments = [{"match": {"left": {"payload": {"protocol": "ip6",
                                                          "field": "daddr"}},
                                     "op": "==",
                                     "right": {"set": daddr_set}}}]
        if self._fw._log_denied in ["unicast", "all"]:
            expr_fragments.append({"log": {"prefix": "RFC3964_IPv4_REJECT: "}})
        expr_fragments.append(self._reject_types_fragment("addr-unreach"))

rules = []
        # WARN: index must be kept in sync with build_default_rules()
        rules.append({"add": {"rule": {"family": "inet",
                                       "table": TABLE_NAME,
                                       "chain": "filter_OUTPUT",
                                       "index": 1,
                                       "expr": expr_fragments}}})
        rules.append({"add": {"rule": {"family": "inet",
                                       "table": TABLE_NAME,
                                       "chain": "filter_FORWARD",
                                       "index": 2,
                                       "expr": expr_fragments}}})
        return rules

def build_policy_rich_source_destination_rules(self, enable, policy, rich_rule):
        table = "filter"

expr_fragments = []
        expr_fragments.append(self._rich_rule_family_fragment(rich_rule.family))
        expr_fragments.append(self._rich_rule_destination_fragment(rich_rule.destination))
        expr_fragments.append(self._rich_rule_source_fragment(rich_rule.source))

rules = []
        rules.append(self._rich_rule_log(policy, rich_rule, enable, table, expr_fragments))
        rules.append(self._rich_rule_audit(policy, rich_rule, enable, table, expr_fragments))
        rules.append(self._rich_rule_action(policy, rich_rule, enable, table, expr_fragments))

return rules

def is_ipv_supported(self, ipv):
        if ipv in ["ipv4", "ipv6", "eb"]:
            return True
        return False

def _set_type_list(self, ipv, type):
        ipv_addr = {
            "ipv4" : "ipv4_addr",
            "ipv6" : "ipv6_addr",
        }
        types = {
            "hash:ip" : ipv_addr[ipv],
            "hash:ip,port" : [ipv_addr[ipv], "inet_proto", "inet_service"],
            "hash:ip,port,ip" : [ipv_addr[ipv], "inet_proto", "inet_service", ipv_addr[ipv]],
            "hash:ip,port,net" : [ipv_addr[ipv], "inet_proto", "inet_service", ipv_addr[ipv]],
            "hash:ip,mark" : [ipv_addr[ipv], "mark"],

"hash:net" : ipv_addr[ipv],
            "hash:net,net" : [ipv_addr[ipv], ipv_addr[ipv]],
            "hash:net,port" : [ipv_addr[ipv], "inet_proto", "inet_service"],
            "hash:net,port,net" : [ipv_addr[ipv], "inet_proto", "inet_service", ipv_addr[ipv]],
            "hash:net,iface" : [ipv_addr[ipv], "ifname"],

"hash:mac" : "ether_addr",
        }
        if type in types:
            return types[type]
        else:
            raise FirewallError(INVALID_TYPE,
                                "ipset type name '%s' is not valid" % type)

def build_set_create_rules(self, name, type, options=None):
        if options and "family" in options and options["family"] == "inet6":
            ipv = "ipv6"
        else:
            ipv = "ipv4"

set_dict = {"table": TABLE_NAME,
                    "name": name,
                    "type": self._set_type_list(ipv, type)}

# Some types need the interval flag
        for t in type.split(":")[1].split(","):
            if t in ["ip", "net", "port"]:
                set_dict["flags"] = ["interval"]
                break

if options:
            if "timeout" in options:
                set_dict["timeout"] = options["timeout"]
            if "maxelem" in options:
                set_dict["size"] = options["maxelem"]

rules = []
        for family in ["inet", "ip", "ip6"]:
            rule_dict = {"family": family}
            rule_dict.update(set_dict)
            rules.append({"add": {"set": rule_dict}})

return rules

def set_create(self, name, type, options=None):
        rules = self.build_set_create_rules(name, type, options)
        self.set_rules(rules, self._fw.get_log_denied())

def set_destroy(self, name):
        for family in ["inet", "ip", "ip6"]:
            rule = {"delete": {"set": {"family": family,
                                       "table": TABLE_NAME,
                                       "name": name}}}
            self.set_rule(rule, self._fw.get_log_denied())

def _set_match_fragment(self, name, match_dest, invert=False):
        type_format = self._fw.ipset.get_ipset(name).type.split(":")[1].split(",")

fragments = []
        for i in range(len(type_format)):
            if type_format[i] == "port":
                fragments.append({"meta": {"key": "l4proto"}})
                fragments.append({"payload": {"protocol": "th",
                                              "field": "dport" if match_dest else "sport"}})
            elif type_format[i] in ["ip", "net", "mac"]:
                fragments.append({"payload": {"protocol": self._set_get_family(name),
                                              "field": "daddr" if match_dest else "saddr"}})
            elif type_format[i] == "iface":
                fragments.append({"meta": {"key": "iifname" if match_dest else "oifname"}})
            elif type_format[i] == "mark":
                fragments.append({"meta": {"key": "mark"}})
            else:
                raise FirewallError("Unsupported ipset type for match fragment: %s" % (type_format[i]))

return {"match": {"left": {"concat": fragments} if len(type_format) > 1 else fragments[0],
                          "op": "!=" if invert else "==",
                          "right": "@" + name}}

def _set_entry_fragment(self, name, entry):
        # convert something like
        #    1.2.3.4,sctp:8080 (type hash:ip,port)
        # to
        #    ["1.2.3.4", "sctp", "8080"]
        obj = self._fw.ipset.get_ipset(name)
        type_format = obj.type.split(":")[1].split(",")
        entry_tokens = entry.split(",")
        if len(type_format) != len(entry_tokens):
            raise FirewallError(INVALID_ENTRY,
                                "Number of values does not match ipset type.")
        fragment = []
        for i in range(len(type_format)):
            if type_format[i] == "port":
                try:
                    index = entry_tokens[i].index(":")
                except ValueError:
                    # no protocol means default tcp
                    fragment.append("tcp")
                    port_str = entry_tokens[i]
                else:
                    fragment.append(entry_tokens[i][:index])
                    port_str = entry_tokens[i][index+1:]

try:
                    index = port_str.index("-")
                except ValueError:
                    fragment.append(port_str)
                else:
                    fragment.append({"range": [port_str[:index], port_str[index+1:]]})

elif type_format[i] in ["ip", "net"]:
                if '-' in entry_tokens[i]:
                    fragment.append({"range": entry_tokens[i].split('-') })
                else:
                    try:
                        index = entry_tokens[i].index("/")
                    except ValueError:
                        addr = entry_tokens[i]
                        if "family" in obj.options and obj.options["family"] == "inet6":
                            addr = normalizeIP6(addr)
                        fragment.append(addr)
                    else:
                        addr = entry_tokens[i][:index]
                        if "family" in obj.options and obj.options["family"] == "inet6":
                            addr = normalizeIP6(addr)
                        fragment.append({"prefix": {"addr": addr,
                                                    "len": int(entry_tokens[i][index+1:])}})
            else:
                fragment.append(entry_tokens[i])
        return [{"concat": fragment}] if len(type_format) > 1 else fragment

def build_set_add_rules(self, name, entry):
        rules = []
        element = self._set_entry_fragment(name, entry)
        for family in ["inet", "ip", "ip6"]:
            rules.append({"add": {"element": {"family": family,
                                              "table": TABLE_NAME,
                                              "name": name,
                                              "elem": element}}})
        return rules

def set_add(self, name, entry):
        rules = self.build_set_add_rules(name, entry)
        self.set_rules(rules, self._fw.get_log_denied())

def set_delete(self, name, entry):
        element = self._set_entry_fragment(name, entry)
        for family in ["inet", "ip", "ip6"]:
            rule = {"delete": {"element": {"family": family,
                                           "table": TABLE_NAME,
                                           "name": name,
                                           "elem": element}}}
            self.set_rule(rule, self._fw.get_log_denied())

def build_set_flush_rules(self, name):
        rules = []
        for family in ["inet", "ip", "ip6"]:
            rule = {"flush": {"set": {"family": family,
                                      "table": TABLE_NAME,
                                      "name": name}}}
            rules.append(rule)
        return rules

def set_flush(self, name):
        rules = self.build_set_flush_rules(name)
        self.set_rules(rules, self._fw.get_log_denied())

def _set_get_family(self, name):
        ipset = self._fw.ipset.get_ipset(name)

if ipset.type == "hash:mac":
            family = "ether"
        elif ipset.options and "family" in ipset.options \
             and ipset.options["family"] == "inet6":
            family = "ip6"
        else:
            family = "ip"

return family

def set_restore(self, set_name, type_name, entries,
                    create_options=None, entry_options=None):
        rules = []
        rules.extend(self.build_set_create_rules(set_name, type_name, create_options))
        rules.extend(self.build_set_flush_rules(set_name))

# avoid large memory usage by chunking the entries
        chunk = 0
        for entry in entries:
            rules.extend(self.build_set_add_rules(set_name, entry))
            chunk += 1
            if chunk >= 1000:
                self.set_rules(rules, self._fw.get_log_denied())
                rules.clear()
                chunk = 0
        else:
            self.set_rules(rules, self._fw.get_log_denied())

MR SKB