summaryrefslogtreecommitdiff
path: root/src/conf_mode/firewall.py
blob: c3b1ee0157a12c4474339808bcb69d67f5eb72d8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
#!/usr/bin/env python3
#
# Copyright (C) 2021-2022 VyOS maintainers and contributors
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 or later as
# published by the Free Software Foundation.
#
# 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/>.

import os
import re

from glob import glob
from json import loads
from sys import exit

from vyos.base import Warning
from vyos.config import Config
from vyos.configdict import node_changed
from vyos.configdiff import get_config_diff, Diff
from vyos.configdep import set_dependents, call_dependents
# from vyos.configverify import verify_interface_exists
from vyos.firewall import fqdn_config_parse
from vyos.firewall import geoip_update
from vyos.template import render
from vyos.utils.process import call
from vyos.utils.process import cmd
from vyos.utils.dict import dict_search_args
from vyos.utils.dict import dict_search_recursive
from vyos.utils.process import process_named_running
from vyos.utils.process import rc_cmd
from vyos import ConfigError
from vyos import airbag
airbag.enable()

nat_conf_script = 'nat.py'
policy_route_conf_script = 'policy-route.py'

nftables_conf = '/run/nftables.conf'

sysfs_config = {
    'all_ping': {'sysfs': '/proc/sys/net/ipv4/icmp_echo_ignore_all', 'enable': '0', 'disable': '1'},
    'broadcast_ping': {'sysfs': '/proc/sys/net/ipv4/icmp_echo_ignore_broadcasts', 'enable': '0', 'disable': '1'},
    'ip_src_route': {'sysfs': '/proc/sys/net/ipv4/conf/*/accept_source_route'},
    'ipv6_receive_redirects': {'sysfs': '/proc/sys/net/ipv6/conf/*/accept_redirects'},
    'ipv6_src_route': {'sysfs': '/proc/sys/net/ipv6/conf/*/accept_source_route', 'enable': '0', 'disable': '-1'},
    'log_martians': {'sysfs': '/proc/sys/net/ipv4/conf/all/log_martians'},
    'receive_redirects': {'sysfs': '/proc/sys/net/ipv4/conf/*/accept_redirects'},
    'send_redirects': {'sysfs': '/proc/sys/net/ipv4/conf/*/send_redirects'},
    'syn_cookies': {'sysfs': '/proc/sys/net/ipv4/tcp_syncookies'},
    'twa_hazards_protection': {'sysfs': '/proc/sys/net/ipv4/tcp_rfc1337'}
}

valid_groups = [
    'address_group',
    'domain_group',
    'network_group',
    'port_group',
    'interface_group'
]

nested_group_types = [
    'address_group', 'network_group', 'mac_group',
    'port_group', 'ipv6_address_group', 'ipv6_network_group'
]

snmp_change_type = {
    'unknown': 0,
    'add': 1,
    'delete': 2,
    'change': 3
}
snmp_event_source = 1
snmp_trap_mib = 'VYATTA-TRAP-MIB'
snmp_trap_name = 'mgmtEventTrap'

def geoip_updated(conf, firewall):
    diff = get_config_diff(conf)
    node_diff = diff.get_child_nodes_diff(['firewall'], expand_nodes=Diff.DELETE, recursive=True)

    out = {
        'name': [],
        'ipv6_name': [],
        'deleted_name': [],
        'deleted_ipv6_name': []
    }
    updated = False

    for key, path in dict_search_recursive(firewall, 'geoip'):
        set_name = f'GEOIP_CC_{path[1]}_{path[2]}_{path[4]}'
        if (path[0] == 'ipv4'):
            out['name'].append(set_name)
        elif (path[0] == 'ipv6'):
            set_name = f'GEOIP_CC6_{path[1]}_{path[2]}_{path[4]}'
            out['ipv6_name'].append(set_name)
            
        updated = True

    if 'delete' in node_diff:
        for key, path in dict_search_recursive(node_diff['delete'], 'geoip'):
            set_name = f'GEOIP_CC_{path[1]}_{path[2]}_{path[4]}'
            if (path[0] == 'ipv4'):
                out['deleted_name'].append(set_name)
            elif (path[0] == 'ipv6'):
                set_name = f'GEOIP_CC_{path[1]}_{path[2]}_{path[4]}'
                out['deleted_ipv6_name'].append(set_name)
            updated = True

    if updated:
        return out

    return False

def get_config(config=None):
    if config:
        conf = config
    else:
        conf = Config()
    base = ['firewall']

    firewall = conf.get_config_dict(base, key_mangling=('-', '_'),
                                    no_tag_node_value_mangle=True,
                                    get_first_key=True,
                                    with_recursive_defaults=True)


    firewall['group_resync'] = bool('group' in firewall or node_changed(conf, base + ['group']))
    if firewall['group_resync']:
        # Update nat and policy-route as firewall groups were updated
        set_dependents('group_resync', conf)

    firewall['geoip_updated'] = geoip_updated(conf, firewall)

    fqdn_config_parse(firewall)

    return firewall

def verify_rule(firewall, rule_conf, ipv6):
    if 'action' not in rule_conf:
        raise ConfigError('Rule action must be defined')

    if 'jump' in rule_conf['action'] and 'jump_target' not in rule_conf:
        raise ConfigError('Action set to jump, but no jump-target specified')

    if 'jump_target' in rule_conf:
        if 'jump' not in rule_conf['action']:
            raise ConfigError('jump-target defined, but action jump needed and it is not defined')
        target = rule_conf['jump_target']
        if not ipv6:
            if target not in dict_search_args(firewall, 'ipv4', 'name'):
                raise ConfigError(f'Invalid jump-target. Firewall name {target} does not exist on the system')
        else:
            if target not in dict_search_args(firewall, 'ipv6', 'name'):
                raise ConfigError(f'Invalid jump-target. Firewall ipv6 name {target} does not exist on the system')

    if 'queue_options' in rule_conf:
        if 'queue' not in rule_conf['action']:
            raise ConfigError('queue-options defined, but action queue needed and it is not defined')
        if 'fanout' in rule_conf['queue_options'] and ('queue' not in rule_conf or '-' not in rule_conf['queue']):
            raise ConfigError('queue-options fanout defined, then queue needs to be defined as a range')

    if 'queue' in rule_conf and 'queue' not in rule_conf['action']:
        raise ConfigError('queue defined, but action queue needed and it is not defined')

    if 'fragment' in rule_conf:
        if {'match_frag', 'match_non_frag'} <= set(rule_conf['fragment']):
            raise ConfigError('Cannot specify both "match-frag" and "match-non-frag"')

    if 'limit' in rule_conf:
        if 'rate' in rule_conf['limit']:
            rate_int = re.sub(r'\D', '', rule_conf['limit']['rate'])
            if int(rate_int) < 1:
                raise ConfigError('Limit rate integer cannot be less than 1')

    if 'ipsec' in rule_conf:
        if {'match_ipsec', 'match_non_ipsec'} <= set(rule_conf['ipsec']):
            raise ConfigError('Cannot specify both "match-ipsec" and "match-non-ipsec"')

    if 'recent' in rule_conf:
        if not {'count', 'time'} <= set(rule_conf['recent']):
            raise ConfigError('Recent "count" and "time" values must be defined')

    tcp_flags = dict_search_args(rule_conf, 'tcp', 'flags')
    if tcp_flags:
        if dict_search_args(rule_conf, 'protocol') != 'tcp':
            raise ConfigError('Protocol must be tcp when specifying tcp flags')

        not_flags = dict_search_args(rule_conf, 'tcp', 'flags', 'not')
        if not_flags:
            duplicates = [flag for flag in tcp_flags if flag in not_flags]
            if duplicates:
                raise ConfigError(f'Cannot match a tcp flag as set and not set')

    if 'protocol' in rule_conf:
        if rule_conf['protocol'] == 'icmp' and ipv6:
            raise ConfigError(f'Cannot match IPv4 ICMP protocol on IPv6, use ipv6-icmp')
        if rule_conf['protocol'] == 'ipv6-icmp' and not ipv6:
            raise ConfigError(f'Cannot match IPv6 ICMP protocol on IPv4, use icmp')

    for side in ['destination', 'source']:
        if side in rule_conf:
            side_conf = rule_conf[side]

            if len({'address', 'fqdn', 'geoip'} & set(side_conf)) > 1:
                raise ConfigError('Only one of address, fqdn or geoip can be specified')

            if 'group' in side_conf:
                if len({'address_group', 'network_group', 'domain_group'} & set(side_conf['group'])) > 1:
                    raise ConfigError('Only one address-group, network-group or domain-group can be specified')

                for group in valid_groups:
                    if group in side_conf['group']:
                        group_name = side_conf['group'][group]

                        fw_group = f'ipv6_{group}' if ipv6 and group in ['address_group', 'network_group'] else group
                        error_group = fw_group.replace("_", "-")

                        if group in ['address_group', 'network_group', 'domain_group']:
                            types = [t for t in ['address', 'fqdn', 'geoip'] if t in side_conf]
                            if types:
                                raise ConfigError(f'{error_group} and {types[0]} cannot both be defined')

                        if group_name and group_name[0] == '!':
                            group_name = group_name[1:]

                        group_obj = dict_search_args(firewall, 'group', fw_group, group_name)

                        if group_obj is None:
                            raise ConfigError(f'Invalid {error_group} "{group_name}" on firewall rule')

                        if not group_obj:
                            Warning(f'{error_group} "{group_name}" has no members!')

            if 'port' in side_conf or dict_search_args(side_conf, 'group', 'port_group'):
                if 'protocol' not in rule_conf:
                    raise ConfigError('Protocol must be defined if specifying a port or port-group')

                if rule_conf['protocol'] not in ['tcp', 'udp', 'tcp_udp']:
                    raise ConfigError('Protocol must be tcp, udp, or tcp_udp when specifying a port or port-group')

            if 'port' in side_conf and dict_search_args(side_conf, 'group', 'port_group'):
                raise ConfigError(f'{side} port-group and port cannot both be defined')

    if 'log_options' in rule_conf:
        if 'log' not in rule_conf or 'enable' not in rule_conf['log']:
            raise ConfigError('log-options defined, but log is not enable')

        if 'snapshot_length' in rule_conf['log_options'] and 'group' not in rule_conf['log_options']:
            raise ConfigError('log-options snapshot-length defined, but log group is not define')

        if 'queue_threshold' in rule_conf['log_options'] and 'group' not in rule_conf['log_options']:
            raise ConfigError('log-options queue-threshold defined, but log group is not define')

    for direction in ['inbound_interface','outbound_interface']:
        if direction in rule_conf:
            if 'interface_name' in rule_conf[direction] and 'interface_group' in rule_conf[direction]:
                raise ConfigError(f'Cannot specify both interface-group and interface-name for {direction}')

def verify_nested_group(group_name, group, groups, seen):
    if 'include' not in group:
        return

    seen.append(group_name)

    for g in group['include']:
        if g not in groups:
            raise ConfigError(f'Nested group "{g}" does not exist')

        if g in seen:
            raise ConfigError(f'Group "{group_name}" has a circular reference')

        if 'include' in groups[g]:
            verify_nested_group(g, groups[g], groups, seen)

def verify(firewall):
    if 'group' in firewall:
        for group_type in nested_group_types:
            if group_type in firewall['group']:
                groups = firewall['group'][group_type]
                for group_name, group in groups.items():
                    verify_nested_group(group_name, group, groups, [])

    if 'ipv4' in firewall:
        for name in ['name','forward','input','output']:
            if name in firewall['ipv4']:
                for name_id, name_conf in firewall['ipv4'][name].items():
                    if 'jump' in name_conf['default_action'] and 'default_jump_target' not in name_conf:
                        raise ConfigError('default-action set to jump, but no default-jump-target specified')
                    if 'default_jump_target' in name_conf:
                        target = name_conf['default_jump_target']
                        if 'jump' not in name_conf['default_action']:
                            raise ConfigError('default-jump-target defined, but default-action jump needed and it is not defined')
                        if name_conf['default_jump_target'] == name_id:
                            raise ConfigError(f'Loop detected on default-jump-target.')
                        ## Now need to check that default-jump-target exists (other firewall chain/name)
                        if target not in dict_search_args(firewall['ipv4'], 'name'):
                            raise ConfigError(f'Invalid jump-target. Firewall name {target} does not exist on the system')

                    if 'rule' in name_conf:
                        for rule_id, rule_conf in name_conf['rule'].items():
                            verify_rule(firewall, rule_conf, False)

    if 'ipv6' in firewall:
        for name in ['name','forward','input','output']:
            if name in firewall['ipv6']:
                for name_id, name_conf in firewall['ipv6'][name].items():
                    if 'jump' in name_conf['default_action'] and 'default_jump_target' not in name_conf:
                        raise ConfigError('default-action set to jump, but no default-jump-target specified')
                    if 'default_jump_target' in name_conf:
                        target = name_conf['default_jump_target']
                        if 'jump' not in name_conf['default_action']:
                            raise ConfigError('default-jump-target defined, but default-action jump needed and it is not defined')
                        if name_conf['default_jump_target'] == name_id:
                            raise ConfigError(f'Loop detected on default-jump-target.')
                        ## Now need to check that default-jump-target exists (other firewall chain/name)
                        if target not in dict_search_args(firewall['ipv6'], 'name'):
                            raise ConfigError(f'Invalid jump-target. Firewall name {target} does not exist on the system')

                    if 'rule' in name_conf:
                        for rule_id, rule_conf in name_conf['rule'].items():
                            verify_rule(firewall, rule_conf, True)

    return None

def generate(firewall):
    if not os.path.exists(nftables_conf):
        firewall['first_install'] = True

    # Determine if conntrack is needed
    firewall['ipv4_conntrack_action'] = 'return'
    firewall['ipv6_conntrack_action'] = 'return'

    for rules, path in dict_search_recursive(firewall, 'rule'):
        if any(('state' in rule_conf or 'connection_status' in rule_conf) for rule_conf in rules.values()):
            if path[0] == 'ipv4':
                firewall['ipv4_conntrack_action'] = 'accept'
            elif path[0] == 'ipv6':
                firewall['ipv6_conntrack_action'] = 'accept'

    render(nftables_conf, 'firewall/nftables.j2', firewall)
    return None

def apply_sysfs(firewall):
    for name, conf in sysfs_config.items():
        paths = glob(conf['sysfs'])
        value = None

        if name in firewall['global_options']:
            conf_value = firewall['global_options'][name]
            if conf_value in conf:
                value = conf[conf_value]
            elif conf_value == 'enable':
                value = '1'
            elif conf_value == 'disable':
                value = '0'

        if value:
            for path in paths:
                with open(path, 'w') as f:
                    f.write(value)

def apply(firewall):
    install_result, output = rc_cmd(f'nft -f {nftables_conf}')
    if install_result == 1:
        raise ConfigError(f'Failed to apply firewall: {output}')

    apply_sysfs(firewall)

    if firewall['group_resync']:
        call_dependents()

    # T970 Enable a resolver (systemd daemon) that checks
    # domain-group/fqdn addresses and update entries for domains by timeout
    # If router loaded without internet connection or for synchronization
    domain_action = 'stop'
    if dict_search_args(firewall, 'group', 'domain_group') or firewall['ip_fqdn'] or firewall['ip6_fqdn']:
        domain_action = 'restart'
    call(f'systemctl {domain_action} vyos-domain-resolver.service')

    if firewall['geoip_updated']:
        # Call helper script to Update set contents
        if 'name' in firewall['geoip_updated'] or 'ipv6_name' in firewall['geoip_updated']:
            print('Updating GeoIP. Please wait...')
            geoip_update(firewall)

    return None

if __name__ == '__main__':
    try:
        c = get_config()
        verify(c)
        generate(c)
        apply(c)
    except ConfigError as e:
        print(e)
        exit(1)