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+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
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+
+ Preamble
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+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
diff --git a/firewall.py b/firewall.py
index 0932c88b50fe25c36e888a77cfbe7aa5cdef7356..621362abbccc762bc366bdb21d54c37964f03021 100644
--- a/firewall.py
+++ b/firewall.py
@@ -1,284 +1,386 @@
#!/usr/bin/python3
-"""
-Module for IP-MAC set management.
+# 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 3 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/>.
+
+# Copyright © 2017 David Sinquin <david.re2o@sinquin.eu>
-Uses ipset to get active ruleset.
-BUGS : requires no spaces in set names (ipset do not manage this properly).
+"""
+Module for nftables set management.
"""
-# À voir:
-# https://unix.stackexchange.com/questions/126009/cause-a-script#126146
+# Dependencies: python3-netaddr, python3-requests, nftables, sudo (optionnal)
#
+# For sudo configuration, create a file in /etc/sudoers.d/ with:
+# "<python_user> ALL = (root) NOPASSWD: /sbin/nftables"
-# Dependencies: python3-netaddr, python3-requests, ipset, sudo
-#
-# Configuration:
-# - create a file in /etc/sudoers.d/ with:
-# "user... ALL = (root) NOPASSWD: /sbin/ipset"
-# - create a set with :
-# "[sudo] ipset create SET_NAME bitmap:ip,mac range IP_NETWORK/MASK"
-# where:
-# - SET_NAME is CONFIG['Firewall']['DEFAULT_NAME']
-# - IP_NETWORK/MASK is probably 10.69.0.0/16
-
-# import ipaddress
-import json
-import subprocess
+# netaddr :
+# - https://pypi.python.org/pypi/netaddr/
+# - https://github.com/drkjam/netaddr/
+# - https://netaddr.readthedocs.io/en/latest/
-import requests
-import netaddr # https://pythonhosted.org/netaddr/index.html
-
-from config import Config
-
-CONFIG = Config()
+import logging
+import subprocess
-class CustomMACFormat(netaddr.mac_unix):
- """Class to print MAC in standard dash-separated format."""
- # Forced to create a class just for that => no need for pylint warning...
- # pylint: disable=too-few-public-methods
- word_fmt = '%.2X'
+import netaddr # MAC, IPv4, IPv6
+import requests
-class RuleSet(object):
- '''
- Manage a set of IP-MAC rules.
+from collections import Iterable
- Rules are couples ('ip', 'mac'):
- - 'ip' is of type netaddr.IPAddress ;
- - 'mac' is of type netaddr.EUI.
- A set have a name, 2 lists of rules (active_rules with kernel loaded rules,
- target_rules with rules to apply), a range, and a type (ipset type).
- '''
+from config import Config
- DEFAULT_NAME = CONFIG['Firewall']['DEFAULT_NAME']
- DEFAULT_TYPE = CONFIG['Firewall']['DEFAULT_TYPE']
- DATA_SOURCE_URL = CONFIG['Source']['DATA_SOURCE_URL']
- LOGIN_URL = CONFIG['Source']['DATA_SOURCE_URL_LOGIN']
- HTTP_AUTHENTICATION_PARAMS = {
- 'username': CONFIG['Default']['USERNAME'],
- 'password': CONFIG['Default']['PASSWORD'],
- }
- def __init__(self, empty=False, name=DEFAULT_NAME, type_=DEFAULT_TYPE):
- self.name = name
- self.active_rules = []
- self.target_rules = []
- self.range_ = None, None
- self.type_ = type_
- if not empty:
- self.get_new_rules()
- self.populate_rules_from_kernel()
-
- def populate_rules_from_kernel(self):
- '''Store currently applied rules from kernel in active_rules.'''
- plaintext_rules = self.get_active_rules(self.name)
- self.parse_kernel_rule_set(plaintext_rules)
+class ExecError(Exception):
+ """Simple class to indicate an error in a process execution."""
+ pass
+class CommandExec:
+ """Simple class to start a command, logging and returning errors if any."""
@staticmethod
- def get_active_rules(set_name):
- '''Get current rule set from kernel and return plaintext data.'''
- ipset_call = subprocess.Popen(
- [
- "/usr/bin/sudo", "/sbin/ipset", "-output", "save",
- "list", set_name
- ],
+ def run_check_output(command, allowed_return_codes=(0,), timeout=15):
+ """
+ Run a command, logging output in case of an error.
+
+ Actual timeout may be twice the given value in seconds."""
+ logging.debug("Command to be run: '%s'", "' '".join(command))
+ process = subprocess.Popen(
+ command,
shell=False,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
universal_newlines=True)
- stdout, stderr = ipset_call.communicate()
- if ipset_call.returncode != 0:
- if ipset_call.returncode == 1 and \
- "The set with the given name does not exist" in stderr:
- raise OSError(
- "ipset \"{}\" do not seem to exist, return code {}\n{}"
- .format(set_name, ipset_call.returncode, stderr))
- raise OSError(
- "Unable to get current ipset, return code: {}\n{}"
- .format(ipset_call.returncode, stderr))
- return stdout.strip()
-
- def parse_kernel_rule_set(self, plaintext_rules):
- """Parse rule set returned from kernel, check and store it."""
try:
- ipset_definition, *ipset_data = plaintext_rules.split("\n")
- except ValueError: # "need more than 0 values to unpack"
- raise ValueError("Invalid ruleset to parse:\n{}".format(
- plaintext_rules))
- self._parse_kernel_ipset_definition(ipset_definition)
- self._parse_kernel_ipsets(ipset_data)
-
- def _parse_kernel_ipset_definition(self, ipset_definition):
+ result = process.communicate(timeout=timeout)
+ return_code = process.wait(timeout=timeout)
+ except subprocess.TimeoutExpired as err:
+ process.kill()
+ raise ExecError from err
+ if return_code not in allowed_return_codes:
+ error_message = ('Error running command: "{}", return code: {}.\n'
+ 'Stderr:\n{}\nStdout:\n{}'.format(
+ '" "'.join(command), return_code, *result))
+ logging.error(error_message)
+ raise ExecError(error_message)
+ return (return_code, *result)
+
+ @classmethod
+ def run(cls, *args, **kwargs):
+ """Run a command without checking outputs."""
+ returncode, _, _ = cls.run_check_output(*args, **kwargs)
+ return returncode
+
+class Parser:
+ """Parsers for commonly used formats."""
+ @staticmethod
+ def MAC(mac):
+ """Check a MAC validity."""
+ return netaddr.EUI(mac, dialect=netaddr.mac_unix_expanded)
+ @staticmethod
+ def IPv4(ip):
+ """Check an IPv4 validity."""
+ return netaddr.IPAddress(ip, version=4)
+ @staticmethod
+ def IPv6(ip):
+ """Check a IPv6 validity."""
+ return netaddr.IPAddress(ip, version=6)
+ @staticmethod
+ def protocol(protocol):
+ """Check a protocol validity."""
+ if protocol in ('tcp', 'udp', 'icmp'):
+ return protocol
+ raise ValueError('Invalid protocol: "{}".'.format(protocol))
+ @staticmethod
+ def port_number(port):
+ """Check a port validity."""
+ port_number = int(port)
+ if 0 <= port_number < 65536:
+ return port_number
+ raise ValueError('Invalid port number: "{}".'.format(port))
+
+class NetfilterSet:
+ """Manage a netfilter set using nftables."""
+
+ TYPES = {'IPv4': 'ipv4_addr', 'IPv6': 'ipv6_addr', 'MAC': 'ether_addr',
+ 'protocol': 'inet_proto', 'port': 'inet_service'}
+
+ FILTERS = {'IPv4': Parser.IPv4, 'IPv6': Parser.IPv6, 'MAC': Parser.MAC,
+ 'protocol': Parser.protocol, 'port': Parser.port_number}
+
+ ADDRESS_FAMILIES = {'ip', 'ip6', 'inet', 'arp', 'bridge', 'netdev'}
+
+ def __init__(self,
+ name,
+ type_, # e.g.: ('MAC', 'IPv4')
+ target_content=None,
+ use_sudo=True,
+ address_family='inet', # Manage both IPv4 and IPv6.
+ table_name='filter'):
+ self.name = name
+ self.content = set()
+ # self.type
+ self.set_type(type_)
+ self.filters = tuple(self.FILTERS[i] for i in self.type)
+ # self.address_family
+ self.set_address_family(address_family)
+ self.table = table_name
+ sudo = ["/usr/bin/sudo"] * int(bool(use_sudo))
+ self.nft = [*sudo, "/usr/sbin/nft"]
+ if target_content:
+ self._target_content = self.validate_set_data(target_content)
+ else:
+ self._target_content = set()
+
+ @property
+ def target_content(self):
+ return self._target_content.copy() # Forbid in-place modification
+
+ @target_content.setter
+ def target_content(self, target_content):
+ self._target_content = self.validate_set_data(target_content)
+
+ def filter(self, elements):
+ return (self.filters[i](element) for i, element in enumerate(elements))
+
+ def set_type(self, type_):
+ """Check set type validity and store it along with a type checker."""
+ for element_type in type_:
+ if element_type not in self.TYPES:
+ raise ValueError('Invalid type: "{}".'.format(element_type))
+ self.type = type_
+
+ def set_address_family(self, address_family='ip'):
+ """Set set addres_family, defaulting to "ip" like nftables."""
+ if address_family not in self.ADDRESS_FAMILIES:
+ raise ValueError(
+ 'Invalid address_family: "{}".'.format(address_family))
+ self.address_family = address_family
+
+ def create_in_kernel(self):
+ """Create the set, removing existing set if needed."""
+ # Delete set if it exists with wrong type
+ current_set = self._get_raw_netfilter_set(parse_elements=False)
+ logging.info(current_set)
+ if current_set is None:
+ self._create_new_set_in_kernel()
+ elif not self.has_type(current_set['type']):
+ self._delete_in_kernel()
+ self._create_new_set_in_kernel()
+
+ def _delete_in_kernel(self):
+ """Delete the set, table and set must exist."""
+ CommandExec.run([
+ *self.nft,
+ 'delete set {addr_family} {table} {set_}'.format(
+ addr_family=self.address_family, table=self.table,
+ set_=self.name)
+ ])
+
+ def _create_new_set_in_kernel(self):
+ """Create the non-existing set, creating table if needed."""
+ create_set = [
+ *self.nft,
+ 'add set {addr_family} {table} {set_} {{ type {type_} ; }}'.format(
+ addr_family=self.address_family, table=self.table,
+ set_=self.name,
+ type_=' . '.join(self.TYPES[i] for i in self.type))
+ ]
+ return_code = CommandExec.run(create_set, allowed_return_codes=(0, 1))
+ if return_code == 0:
+ return # Set creation successful.
+ # return_code was 1, one error was detected in the rules.
+ # Attempt to create the table first.
+ create_table = [*self.nft, 'add table {addr_family} {table}'.format(
+ addr_family=self.address_family, table=self.table)]
+ CommandExec.run(create_table)
+ CommandExec.run(create_set)
+
+ def validate_set_data(self, set_data):
"""
- Parse first line of ipset output, check and store data.
+ Validate data, returning it or raising a ValueError.
- First line should be: "'create' setname type 'range' range"
+ For MAC-IPv4 set, data must be an iterable of (MAC, IPv4) iterables.
"""
- words = ipset_definition.split(' ')
- if len(words) < 5 or words[0] != 'create':
- raise ValueError(
- "Unexpected string, got '{}' in stead of 'create ...'" \
- .format(ipset_definition))
- if self.name is not None:
- self.name = words[1]
- else:
- # Managing spaces in set name (even if use is strongly discouraged)
+ set_ = set()
+ errors = []
+ for n_uplet in set_data:
try:
- words[1] = ' '.join(words[1 : len(self.name.split(' ')) + 1])
- except IndexError:
- raise ValueError(
- "Wrong set described, got '{}', expecting '{}'".format(
- ipset_definition, self.name))
- if words[1] != self.name:
- raise ValueError(
- "Wrong set described, got '{}', expecting '{}'".format(
- words[1], self.name))
- if len(words) < 5:
+ set_.add(tuple(self.filter(n_uplet)))
+ except Exception as err:
+ errors.append(err)
+ if errors:
raise ValueError(
- "Too short string, got '{}' in stead of 'create ...'" \
- .format(ipset_definition))
- if self.type_ is None:
- self.type_ = words[2]
- elif self.type_ != words[2]:
- raise ValueError(
- "Wrong set described, got '{}', expecting '{}'".format(
- words[1], self.type_))
- if words[3] == 'range':
- range_ = tuple(map(netaddr.IPAddress, words[4].split('-')))
- if self.range_ == (None, None):
- self.range_ = range_
- elif self.range_ != range_:
- raise ValueError(
- "Wrong range, got '{}', expecting '{}'".format(
- words[4], self._range_str()))
+ 'Error parsing data, encountered the folowing {} errors.\n"{}"'
+ .format(len(errors), '",\n"'.join(map(str, errors))))
+ return set_
+
+ def _apply_target_content(self):
+ """Change netfilter set content to target set."""
+ current_set = self.get_netfilter_set_content()
+ if current_set is None:
+ raise ValueError('Cannot change "{}" netfilter set content: set '
+ 'do not exist in "{}" "{}".'.format(
+ self.name, self.address_family, self.table))
+ to_delete = current_set - self._target_content
+ to_add = self._target_content - current_set
+ self._change_set_content(delete=to_delete, add=to_add)
+
+ def _change_set_content(self, delete=None, add=None):
+ todo = [tuple_ for tuple_ in (('add', add), ('delete', delete))
+ if tuple_[1]]
+ for action, elements in todo:
+ content = ', '.join(' . '.join(str(element) for element in tuple_)
+ for tuple_ in elements)
+ command = [
+ *self.nft,
+ '{action} element {addr_family} {table} {set_} {{{content}}}' \
+ .format(action=action, addr_family=self.address_family,
+ table=self.table, set_=self.name, content=content)
+ ]
+ CommandExec.run(command)
+
+ def _get_raw_netfilter_set(self, parse_elements=True):
+ """Return a dict describing the netfilter set matching self or None."""
+ _, stdout, _ = CommandExec.run_check_output(
+ [*self.nft, '-nn', 'list set {addr_family} {table} {set_}'.format(
+ addr_family=self.address_family, table=self.table,
+ set_=self.name)],
+ allowed_return_codes=(0, 1) # In case table do not exist
+ )
+ if not stdout:
+ return None
else:
- raise ValueError(
- "ipset definition has no range: '{}'." \
- .format(ipset_definition))
-
- def _parse_kernel_ipsets(self, ipsets):
- """Parse lines of ipset output from kernel, storing data."""
- for line in ipsets:
- words = line.split(' ')
- if words[0:2] == ['add', self.name]:
- ip, mac = words[2].split(',')
- ip = netaddr.IPAddress(ip)
- mac = netaddr.EUI(mac, dialect=CustomMACFormat)
- if self.in_range(ip):
- self.active_rules.append((ip, mac))
+ netfilter_set = self._parse_netfilter_set_string(stdout)
+ if netfilter_set['name'] != self.name \
+ or netfilter_set['address_family'] != self.address_family \
+ or netfilter_set['table'] != self.table \
+ or netfilter_set['type'] != [
+ self.TYPES[type_] for type_ in self.type]:
+ raise ValueError('Did not get the right set, too wrong to fix.')
+ if parse_elements:
+ if netfilter_set['raw_content']:
+ netfilter_set['content'] = self.validate_set_data((
+ (element.strip() for element in n_uplet.split(' . '))
+ for n_uplet in netfilter_set['raw_content'].split(',')))
else:
- raise ValueError(
- 'IP {} not in range {}.'.format(ip, self._range_str()))
- else:
- raise ValueError(
- "Unable to parse current ipset: unexpected output: {}"
- .format(line))
-
- def in_range(self, ip):
- """Test if ip is in the set range."""
- inf, sup = self.range_
- return inf.version == ip.version \
- and hex(inf) <= hex(ip) <= hex(sup)
-
- def _range_str(self):
- """Returns the set range in string format IP_1-IP_2."""
- return "{}-{}".format(*map(str, self.range_))
-
- def get_new_rules(self):
- '''Get rules to apply from re2o in self.target_rules.'''
- json_rules = self.get_json_rules()
- self.parse_json_rules(json_rules)
+ netfilter_set['content'] = set()
+ return netfilter_set
- @classmethod
- def get_json_rules(cls, data_source_url=None, login_url=None):
- """Get JSON rules from Re2o and return a JSON string."""
- if data_source_url is None:
- data_source_url = cls.DATA_SOURCE_URL
- if login_url is None:
- login_url = cls.LOGIN_URL
- login_connexion = requests.post(
- login_url, data=cls.HTTP_AUTHENTICATION_PARAMS)
- json_data = requests.post(
- data_source_url, cookies=login_connexion.cookies)
- return json_data.content.decode()
-
- def parse_json_rules(self, json_rules):
+ @staticmethod
+ def _parse_netfilter_set_string(set_string):
"""
- Parse JSON rules and store them in target_rules.
+ Parse netfilter set definition and return set as dict.
- Fragile code due to re2o REST export.
+ Do not validate content type against detected set type.
+ Return a dict with 'name', 'address_family', 'table', 'type',
+ 'raw_content' keys (all strings, 'raw_content' can be None).
+ Raise ValueError in case of unexpected syntax.
"""
- data = json.loads(json_rules.strip())
- ip = None
- mac = None
- for couple in data:
- if 'ipv4' in couple:
- ip = couple['ipv4'].get('ipv4', None)
- if ip is None:
- raise ValueError(
- 'Missing IP in IP, MAC couple: "{}".'.format(couple))
- if couple['ipv4']['ip_type'] != 'adhérent':
- continue # Skipping useless IP
- ip = netaddr.IPAddress(ip)
- elif 'ipv6' in couple:
- raise NotImplementedError('No IPv6 support yet.')
- #ip = netaddr.IPAddress(couple['ipv6'])
- else:
- raise ValueError(
- 'Missing IP in IP, MAC couple: "{}".'.format(couple))
- if 'mac_address' in couple:
- mac = netaddr.EUI(couple['mac_address'],
- dialect=CustomMACFormat)
- else:
- raise ValueError(
- 'Missing MAC in IP, MAC couple: "{}".'.format(couple))
- if self.in_range(ip):
- self.target_rules.append((ip, mac))
+ # Fragile code since using lexer / parser would be quite heavy
+ lines = [line.lstrip('\t ') for line in set_string.strip().splitlines()]
+ errors = []
+ # 5 lines when empty, 6 with elements = { … }
+ if len(lines) not in (5, 6):
+ errors.append('Error, expecting 5 or 6 lines for set definition, '
+ 'got "{}".'.format(set_string))
+
+ line_iterator = iter(lines)
+ set_definition = {}
+
+ line = next(line_iterator).split(' ') # line #1
+ # 'table <address_family> <chain> {'
+ if len(line) != 4 or line[0] != 'table' or line[3] != '{':
+ errors.append(
+ 'Cannot parse table definition, expecting "type <addr_family> '
+ '<table> {{", got "{}".'.format(' '.join(line)))
+ else:
+ set_definition['address_family'] = line[1]
+ set_definition['table'] = line[2]
+
+ line = next(line_iterator).split(' ') # line #2
+ # 'set <name> {'
+ if len(line) != 3 or line[0] != 'set' or line[2] != '{':
+ errors.append('Cannot parse set definition, expecting "set <name> '
+ '{{", got "{}".' .format(' '.join(line)))
+ else:
+ set_definition['name'] = line[1]
+
+ line = next(line_iterator).split(' ') # line #3
+ # 'type <type> [. <type>]...'
+ if len(line) < 2 or len(line) % 2 != 0 or line[0] != 'type' \
+ or any(element != '.' for element in line[2::2]):
+ errors.append(
+ 'Cannot parse type definition, expecting "type <type> '
+ '[. <type>]...", got "{}".'.format(' '.join(line)))
+ else:
+ set_definition['type'] = line[1::2]
+
+ if len(lines) == 6:
+ # set is not empty, getting raw elements
+ line = next(line_iterator) # Unsplit line #4
+ if line[:13] != 'elements = { ' or line[-1] != '}':
+ errors.append('Cannot parse set elements, expecting "elements '
+ '= {{ <…>}}", got "{}".'.format(line))
else:
- raise ValueError(
- 'IP {} not in range {}.'.format(ip, self._range_str()))
-
- def add_rule_to_kernel(self, rule):
- """Add a rule to kernel set."""
- self._add_del_rule_to_kernel(rule, 'add')
-
- def del_rule_to_kernel(self, rule):
- """Del a rule from kernel set."""
- self._add_del_rule_to_kernel(rule, 'del')
-
- def _add_del_rule_to_kernel(self, rule, action):
- """Add or del a rule to/from kernel set."""
- if action not in ['add', 'del']:
- raise ValueError((
- "Action must be either 'add' or 'del', "
- "{} is not a valid action.".format(action)))
- # No check that IP is in right range
- ipset_call = subprocess.Popen(
- [
- "/usr/bin/sudo", "/sbin/ipset",
- action, self.name,
- "{ip},{mac}".format(ip=rule[0], mac=rule[1])
- ],
- shell=False,
- stdout=subprocess.PIPE,
- stderr=subprocess.PIPE,
- universal_newlines=True)
- stdout, stderr = ipset_call.communicate()
- if ipset_call.returncode != 0:
- raise OSError(
- "Unable to get current ipset, return code: {}\n{}"
- .format(ipset_call.returncode, stderr))
- return stdout.strip()
-
- def apply_target_rules(self):
- """Apply changes needed to get target rules applied by firewall."""
- rules_to_add = set(self.target_rules) - set(self.active_rules)
- rules_to_del = set(self.active_rules) - set(self.target_rules)
- for rule in rules_to_del:
- self.del_rule_to_kernel(rule)
- for rule in rules_to_add:
- self.add_rule_to_kernel(rule)
+ set_definition['raw_content'] = line[13:-1].strip()
+ else:
+ set_definition['raw_content'] = None
+
+ # last two lines
+ for i in range(2):
+ line = next(line_iterator).split(' ')
+ if line != ['}']:
+ errors.append(
+ 'No normal end to set definition, expecting "}}" on line '
+ '{}, got "{}".'.format(i+5, ' '.join(line)))
+ if errors:
+ raise ValueError('The following error(s) were encountered while '
+ 'parsing set.\n"{}"'.format('",\n"'.join(errors)))
+ return set_definition
+
+ def get_netfilter_set_content(self):
+ """Return current set content from netfilter."""
+ netfilter_set = self._get_raw_netfilter_set(parse_elements=True)
+ if netfilter_set is None:
+ return None
+ else:
+ return netfilter_set['content']
+
+ def has_type(self, type_):
+ """Check if some type match the set's one."""
+ return tuple(self.TYPES[t] for t in self.type) == tuple(type_)
+ def manage(self):
+ """Create set if needed and populate it with target content."""
+ self.create_in_kernel()
+ self._apply_target_content()
+
+class Firewall:
+ """Manages the firewall using nftables."""
+
+ @staticmethod
+ def manage_sets(sets, address_family=None, table=None, use_sudo=None):
+ CONFIG = Config()
+ address_family = address_family or CONFIG['address_family'] or 'inet'
+ table = table or CONFIG['table'] or 'filter'
+ sudo = use_sudo or (use_sudo is None and CONFIG['use_sudo'])
+ for set_ in sets:
+ NetfilterSet(
+ name=set_['name'],
+ type_=set_['type'],
+ target_content=set_['content'],
+ use_sudo=sudo,
+ address_family=address_family,
+ table_name=table).manage()
diff --git a/nft_ruleset.exemple b/nft_ruleset.exemple
new file mode 100644
index 0000000000000000000000000000000000000000..934ee25930ae8176c3ae06bbf35386222585a572
--- /dev/null
+++ b/nft_ruleset.exemple
@@ -0,0 +1,83 @@
+#!/usr/sbin/nft
+
+# TODO:
+# - manage fail2ban
+# - manage nat:
+# ip . jump ports @dest_ports
+# ip @verdict with verdict { ip => jump nat port X-Y}
+
+
+
+define internet_iface = eth0
+define public_iface = eth1
+define server_iface = eth2
+define users_iface = eth3
+
+
+# Not using "flush ruleset" to keep defined sets
+flush table arp
+flush table bridge
+flush table inet
+flush table ip
+flush table ip6
+flush table netdev
+
+
+table inet nat {
+ chain prerouting {
+ type nat hook prerouting priority 0
+ }
+ chain postrouting {
+ type nat hook postrouting priority 0
+ }
+}
+
+table inet filter {
+ set user_ip_mac {
+ type ipv4_addr . ether_addr
+ }
+ set user_ip6_mac {
+ type ipv6_addr . ether_addr
+ }
+
+ set public_server_allowed_tcp_in {
+ type ipv4_addr . inet_service
+ }
+ set public_server_allowed_tcp_out {
+ type ipv4_addr . inet_service
+ }
+ set public_server_allowed_udp_in {
+ type ipv4_addr . inet_service
+ }
+ set public_server_allowed_udp_out {
+ type ipv4_addr . inet_service
+ }
+
+ chain input {
+ type filter hook input priority 0
+ policy reject
+ meta iif $users_iface not ip saddr . ether saddr @user_ip_mac drop
+ meta iif $users_iface not ip6 saddr . ether saddr @user_ip6_mac drop
+ ct state established accept
+ ip tcp dport 22 accept
+ icmp type { echo-request, echo-reply, destination-unreachable, time-exceeded, parameter-problem, source-quench } accept
+ icmpv6 type { nd-neighbor-solicit, echo-request, nd-router-advert, nd-neighbor-advert } accept
+ }
+ chain output {
+ type filter hook output priority 0;
+ policy reject
+ meta oif $users_iface not ip saddr . ether saddr @user_ip_mac drop
+ meta oif $users_iface not ip6 saddr . ether saddr @user_ip6_mac drop
+ ct state established accept
+ }
+ chain forward {
+ type filter hook forward priority 0;
+ policy reject
+ meta iif $users_iface not ip saddr . ether saddr @user_ip_mac drop
+ meta iif $users_iface not ip6 saddr . ether saddr @user_ip6_mac drop
+ meta oif $public_iface not ip daddr . tcp dport @public_server_allowed_tcp_in accept
+ meta iif $public_iface not ip saddr . tcp dport @public_server_allowed_tcp_out accept
+ meta oif $public_iface not ip daddr . udp dport @public_server_allowed_udp_in accept
+ meta iif $public_iface not ip saddr . udp dport @public_server_allowed_udp_out accept
+ }
+}
diff --git a/test_firewall_nftables.py b/test_firewall_nftables.py
new file mode 100644
index 0000000000000000000000000000000000000000..d21b5a71da10f5a44c51ff93afee891df6196e37
--- /dev/null
+++ b/test_firewall_nftables.py
@@ -0,0 +1,40 @@
+#!/usr/bin/env python3
+
+import logging
+
+from firewall import NetfilterSet
+
+
+def test_netfilter_sets():
+ """Run a set of tests to ensure not everything is broken."""
+ # MAC, IPv4 set
+ NetfilterSet(
+ target_content=(
+ ['01:02:03:04:05:06', '1.2.3.4'],
+ ('0a-0b-0c-0d-0e-0f', '10.11.12.13'),
+ ),
+ type_=('MAC', 'IPv4'),
+ name='test_ipv4_set',
+ use_sudo=False,
+ ).manage()
+ # MAC, IPv6 set
+ NetfilterSet(
+ target_content={('0a-0b-0c-0d-0e-0f', 'fe80::42')},
+ name='test_set',
+ type_=['MAC', 'IPv6'],
+ address_family='ip6', table_name='mangle'
+ ).manage()
+ # Whatever
+ mac_ipv4_ipv6_port_set = NetfilterSet(
+ name='plop',
+ type_=('MAC', 'IPv4', 'IPv6', 'protocol', 'port'),
+ target_content={
+ ('0a-0b-0c-0d-0e-0f', '10.11.12.13', 'fe80::42', 'tcp', 53),})
+ mac_ipv4_ipv6_port_set.manage()
+ mac_ipv4_ipv6_port_set.target_content = ((
+ '12-34-56-78-90-ab', '10.9.8.7', 'fe80:42::', 'udp', 53),)
+ mac_ipv4_ipv6_port_set.manage()
+
+if __name__ == '__main__':
+ logging.basicConfig(format='%(levelname)s:%(message)s', level=logging.DEBUG)
+ test_netfilter_sets()