summaryrefslogtreecommitdiff
path: root/src/conf_mode/nat66.py
blob: 95dfae3a5c06e4c7e211799942c37b39cc8603ef (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
#!/usr/bin/env python3
#
# Copyright (C) 2020-2024 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

from sys import exit

from vyos.base import Warning
from vyos.config import Config
from vyos.configdep import set_dependents, call_dependents
from vyos.template import render
from vyos.utils.dict import dict_search
from vyos.utils.kernel import check_kmod
from vyos.utils.network import interface_exists
from vyos.utils.process import cmd
from vyos.utils.process import run
from vyos.template import is_ipv6
from vyos import ConfigError
from vyos import airbag
airbag.enable()

k_mod = ['nft_nat', 'nft_chain_nat']

nftables_nat66_config = '/run/nftables_nat66.nft'

def get_config(config=None):
    if config:
        conf = config
    else:
        conf = Config()

    base = ['nat66']
    nat = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)

    set_dependents('conntrack', conf)

    if not conf.exists(base):
        nat['deleted'] = ''
        return nat

    nat['firewall_group'] = conf.get_config_dict(['firewall', 'group'], key_mangling=('-', '_'), get_first_key=True,
                                    no_tag_node_value_mangle=True)

    # Remove dynamic firewall groups if present:
    if 'dynamic_group' in nat['firewall_group']:
        del nat['firewall_group']['dynamic_group']

    return nat

def verify(nat):
    if not nat or 'deleted' in nat:
        # no need to verify the CLI as NAT66 is going to be deactivated
        return None

    if dict_search('source.rule', nat):
        for rule, config in dict_search('source.rule', nat).items():
            err_msg = f'Source NAT66 configuration error in rule {rule}:'

            if 'outbound_interface' in config:
                if 'name' in config['outbound_interface'] and 'group' in config['outbound_interface']:
                    raise ConfigError(f'{err_msg} cannot specify both interface group and interface name for nat source rule "{rule}"')
                elif 'name' in config['outbound_interface']:
                    interface_name = config['outbound_interface']['name']
                    if interface_name not in 'any':
                        if interface_name.startswith('!'):
                            interface_name = interface_name[1:]
                        if not interface_exists(interface_name):
                            Warning(f'Interface "{interface_name}" for source NAT66 rule "{rule}" does not exist!')

            addr = dict_search('translation.address', config)
            if addr != None:
                if addr != 'masquerade' and not is_ipv6(addr):
                    raise ConfigError(f'IPv6 address {addr} is not a valid address')
            else:
                if 'exclude' not in config:
                    raise ConfigError(f'{err_msg} translation address not specified')

            prefix = dict_search('source.prefix', config)
            if prefix != None:
                if not is_ipv6(prefix):
                    raise ConfigError(f'{err_msg} source-prefix not specified')

    if dict_search('destination.rule', nat):
        for rule, config in dict_search('destination.rule', nat).items():
            err_msg = f'Destination NAT66 configuration error in rule {rule}:'

            if 'inbound_interface' in config:
                if 'name' in config['inbound_interface'] and 'group' in config['inbound_interface']:
                    raise ConfigError(f'{err_msg} cannot specify both interface group and interface name for destination nat rule "{rule}"')
                elif 'name' in config['inbound_interface']:
                    interface_name = config['inbound_interface']['name']
                    if interface_name not in 'any':
                        if interface_name.startswith('!'):
                            interface_name = interface_name[1:]
                        if not interface_exists(interface_name):
                            Warning(f'Interface "{interface_name}" for destination NAT66 rule "{rule}" does not exist!')

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

    return None

def generate(nat):
    if not os.path.exists(nftables_nat66_config):
        nat['first_install'] = True

    render(nftables_nat66_config, 'firewall/nftables-nat66.j2', nat)

    # dry-run newly generated configuration
    tmp = run(f'nft --check --file {nftables_nat66_config}')
    if tmp > 0:
        raise ConfigError('Configuration file errors encountered!')

    return None

def apply(nat):
    check_kmod(k_mod)

    cmd(f'nft --file {nftables_nat66_config}')

    if not nat or 'deleted' in nat:
        os.unlink(nftables_nat66_config)

    call_dependents()

    return None

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