summaryrefslogtreecommitdiff
path: root/python/vyos/validate.py
blob: 6dfa1139f0d00c39ab1a25fc43fee7c408e7e358 (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
# Copyright 2018-2021 VyOS maintainers and contributors <maintainers@vyos.io>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library.  If not, see <http://www.gnu.org/licenses/>.

# Important note when you are adding new validation functions:
#
# The Control class will analyse the signature of the function in this file
# and will build the parameters to be passed to it.
#
# The parameter names "ifname" and "self" will get the Interface name and class
# parameters with default will be left unset
# all other paramters will receive the value to check

def is_ipv6_link_local(addr):
    """ Check if addrsss is an IPv6 link-local address. Returns True/False """
    from ipaddress import ip_interface
    from vyos.template import is_ipv6
    addr = addr.split('%')[0]
    if is_ipv6(addr):
        if ip_interface(addr).is_link_local:
            return True

    return False

def _are_same_ip(one, two):
    from socket import AF_INET
    from socket import AF_INET6
    from socket import inet_pton
    from vyos.template import is_ipv4
    # compare the binary representation of the IP
    f_one = AF_INET if is_ipv4(one) else AF_INET6
    s_two = AF_INET if is_ipv4(two) else AF_INET6
    return inet_pton(f_one, one) == inet_pton(f_one, two)

def is_intf_addr_assigned(intf, address, vrf=None) -> bool:
    """
    Verify if the given IPv4/IPv6 address is assigned to specific interface.
    It can check both a single IP address (e.g. 192.0.2.1 or a assigned CIDR
    address 192.0.2.1/24.
    """
    from vyos.template import is_ipv4
    from vyos.util import get_interface_config

    from netifaces import ifaddresses
    from netifaces import AF_INET
    from netifaces import AF_INET6

    # check if the requested address type is configured at all
    # {
    # 17: [{'addr': '08:00:27:d9:5b:04', 'broadcast': 'ff:ff:ff:ff:ff:ff'}],
    # 2:  [{'addr': '10.0.2.15', 'netmask': '255.255.255.0', 'broadcast': '10.0.2.255'}],
    # 10: [{'addr': 'fe80::a00:27ff:fed9:5b04%eth0', 'netmask': 'ffff:ffff:ffff:ffff::'}]
    # }
    try:
        ifaces = ifaddresses(intf)
    except ValueError as e:
        print(e)
        return False

    # Check if interface belongs to requested VRF. If interfaces does not
    # belong to requested VRF - bail out early
    tmp = get_interface_config(intf)
    if 'master' in tmp and tmp['master'] != vrf:
        return False

    # determine IP version (AF_INET or AF_INET6) depending on passed address
    addr_type = AF_INET if is_ipv4(address) else AF_INET6

    # Check every IP address on this interface for a match
    netmask = None
    if '/' in address:
        address, netmask = address.split('/')
    for ip in ifaces.get(addr_type,[]):
        # ip can have the interface name in the 'addr' field, we need to remove it
        # {'addr': 'fe80::a00:27ff:fec5:f821%eth2', 'netmask': 'ffff:ffff:ffff:ffff::'}
        ip_addr = ip['addr'].split('%')[0]

        if not _are_same_ip(address, ip_addr):
            continue

        # we do not have a netmask to compare against, they are the same
        if not netmask:
            return True

        prefixlen = ''
        if is_ipv4(ip_addr):
            prefixlen = sum([bin(int(_)).count('1') for _ in ip['netmask'].split('.')])
        else:
            prefixlen = sum([bin(int(_,16)).count('1') for _ in ip['netmask'].split('/')[0].split(':') if _])

        if str(prefixlen) == netmask:
            return True

    return False

def is_addr_assigned(addr, vrf=None) -> bool:
    """
    Verify if the given IPv4/IPv6 address is assigned to any interface
    """
    from netifaces import interfaces
    for intf in interfaces():
        tmp = is_intf_addr_assigned(intf, addr, vrf)
        if tmp == True:
            return True

    return False

def is_loopback_addr(addr):
    """ Check if supplied IPv4/IPv6 address is a loopback address """
    from ipaddress import ip_address
    return ip_address(addr).is_loopback

def is_subnet_connected(subnet, primary=False):
    """
    Verify is the given IPv4/IPv6 subnet is connected to any interface on this
    system.

    primary check if the subnet is reachable via the primary IP address of this
    interface, or in other words has a broadcast address configured. ISC DHCP
    for instance will complain if it should listen on non broadcast interfaces.

    Return True/False
    """
    from ipaddress import ip_address
    from ipaddress import ip_network

    from netifaces import ifaddresses
    from netifaces import interfaces
    from netifaces import AF_INET
    from netifaces import AF_INET6

    from vyos.template import is_ipv6

    # determine IP version (AF_INET or AF_INET6) depending on passed address
    addr_type = AF_INET
    if is_ipv6(subnet):
        addr_type = AF_INET6

    for interface in interfaces():
        # check if the requested address type is configured at all
        if addr_type not in ifaddresses(interface).keys():
            continue

        # An interface can have multiple addresses, but some software components
        # only support the primary address :(
        if primary:
            ip = ifaddresses(interface)[addr_type][0]['addr']
            if ip_address(ip) in ip_network(subnet):
                return True
        else:
            # Check every assigned IP address if it is connected to the subnet
            # in question
            for ip in ifaddresses(interface)[addr_type]:
                # remove interface extension (e.g. %eth0) that gets thrown on the end of _some_ addrs
                addr = ip['addr'].split('%')[0]
                if ip_address(addr) in ip_network(subnet):
                    return True

    return False


def assert_boolean(b):
    if int(b) not in (0, 1):
        raise ValueError(f'Value {b} out of range')


def assert_range(value, lower=0, count=3):
    if int(value, 16) not in range(lower, lower+count):
        raise ValueError("Value out of range")


def assert_list(s, l):
    if s not in l:
        o = ' or '.join([f'"{n}"' for n in l])
        raise ValueError(f'state must be {o}, got {s}')


def assert_number(n):
    if not str(n).isnumeric():
        raise ValueError(f'{n} must be a number')


def assert_positive(n, smaller=0):
    assert_number(n)
    if int(n) < smaller:
        raise ValueError(f'{n} is smaller than {smaller}')


def assert_mtu(mtu, ifname):
    assert_number(mtu)

    import json
    from vyos.util import cmd
    out = cmd(f'ip -j -d link show dev {ifname}')
    # [{"ifindex":2,"ifname":"eth0","flags":["BROADCAST","MULTICAST","UP","LOWER_UP"],"mtu":1500,"qdisc":"pfifo_fast","operstate":"UP","linkmode":"DEFAULT","group":"default","txqlen":1000,"link_type":"ether","address":"08:00:27:d9:5b:04","broadcast":"ff:ff:ff:ff:ff:ff","promiscuity":0,"min_mtu":46,"max_mtu":16110,"inet6_addr_gen_mode":"none","num_tx_queues":1,"num_rx_queues":1,"gso_max_size":65536,"gso_max_segs":65535}]
    parsed = json.loads(out)[0]
    min_mtu = int(parsed.get('min_mtu', '0'))
    # cur_mtu = parsed.get('mtu',0),
    max_mtu = int(parsed.get('max_mtu', '0'))
    cur_mtu = int(mtu)

    if (min_mtu and cur_mtu < min_mtu) or cur_mtu < 68:
        raise ValueError(f'MTU is too small for interface "{ifname}": {mtu} < {min_mtu}')
    if (max_mtu and cur_mtu > max_mtu) or cur_mtu > 65536:
        raise ValueError(f'MTU is too small for interface "{ifname}": {mtu} > {max_mtu}')


def assert_mac(m):
    split = m.split(':')
    size = len(split)

    # a mac address consits out of 6 octets
    if size != 6:
        raise ValueError(f'wrong number of MAC octets ({size}): {m}')

    octets = []
    try:
        for octet in split:
            octets.append(int(octet, 16))
    except ValueError:
        raise ValueError(f'invalid hex number "{octet}" in : {m}')

    # validate against the first mac address byte if it's a multicast
    # address
    if octets[0] & 1:
        raise ValueError(f'{m} is a multicast MAC address')

    # overall mac address is not allowed to be 00:00:00:00:00:00
    if sum(octets) == 0:
        raise ValueError('00:00:00:00:00:00 is not a valid MAC address')

    if octets[:5] == (0, 0, 94, 0, 1):
        raise ValueError(f'{m} is a VRRP MAC address')

def has_address_configured(conf, intf):
    """
    Checks if interface has an address configured.
    Checks the following config nodes:
    'address', 'ipv6 address eui64', 'ipv6 address autoconf'

    Returns True if interface has address configured, False if it doesn't.
    """
    from vyos.ifconfig import Section
    ret = False

    old_level = conf.get_level()
    conf.set_level([])

    intfpath = 'interfaces ' + Section.get_config_path(intf)
    if ( conf.exists(f'{intfpath} address') or
            conf.exists(f'{intfpath} ipv6 address autoconf') or
            conf.exists(f'{intfpath} ipv6 address eui64') ):
        ret = True

    conf.set_level(old_level)
    return ret