summaryrefslogtreecommitdiff
path: root/src/op_mode/show_dhcpv6.py
blob: f70f042983558ed45b3208d09b85c9c69a87de3a (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
#!/usr/bin/env python3
#
# Copyright (C) 2018-2020 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/>.
#
# TODO: merge with show_dhcp.py

from json import dumps
from argparse import ArgumentParser
from ipaddress import ip_address
from tabulate import tabulate
from sys import exit
from collections import OrderedDict
from datetime import datetime

from isc_dhcp_leases import Lease, IscDhcpLeases

from vyos.config import Config
from vyos.util import call

lease_file = "/config/dhcpdv6.leases"
pool_key = "shared-networkname"

lease_display_fields = OrderedDict()
lease_display_fields['ip'] = 'IPv6 address'
lease_display_fields['state'] = 'State'
lease_display_fields['last_comm'] = 'Last communication'
lease_display_fields['expires'] = 'Lease expiration'
lease_display_fields['remaining'] = 'Remaining'
lease_display_fields['type'] = 'Type'
lease_display_fields['pool'] = 'Pool'
lease_display_fields['iaid_duid'] = 'IAID_DUID'

lease_valid_states = ['all', 'active', 'free', 'expired', 'released', 'abandoned', 'reset', 'backup']

def in_pool(lease, pool):
    if pool_key in lease.sets:
        if lease.sets[pool_key] == pool:
            return True

    return False

def format_hex_string(in_str):
    out_str = ""

    # if input is divisible by 2, add : every 2 chars
    if len(in_str) > 0 and len(in_str) % 2 == 0:
        out_str = ':'.join(a+b for a,b in zip(in_str[::2], in_str[1::2]))
    else:
        out_str = in_str

    return out_str

def utc_to_local(utc_dt):
    return datetime.fromtimestamp((utc_dt - datetime(1970,1,1)).total_seconds())

def get_lease_data(lease):
    data = {}

    # isc-dhcp lease times are in UTC so we need to convert them to local time to display
    try:
        data["expires"] = utc_to_local(lease.end).strftime("%Y/%m/%d %H:%M:%S")
    except:
        data["expires"] = ""

    try:
        data["last_comm"] = utc_to_local(lease.last_communication).strftime("%Y/%m/%d %H:%M:%S")
    except:
        data["last_comm"] = ""

    try:
        data["remaining"] = lease.end - datetime.utcnow()
        # negative timedelta prints wrong so bypass it
        if (data["remaining"].days >= 0):
            # substraction gives us a timedelta object which can't be formatted with strftime
            # so we use str(), split gets rid of the microseconds
            data["remaining"] = str(data["remaining"]).split('.')[0]
        else:
            data["remaining"] = ""
    except:
        data["remaining"] = ""

    # isc-dhcp records lease declarations as ia_{na|ta|pd} IAID_DUID {...}
    # where IAID_DUID is the combined IAID and DUID
    data["iaid_duid"] = format_hex_string(lease.host_identifier_string)

    lease_types_long = {"na": "non-temporary", "ta": "temporary", "pd": "prefix delegation"}
    data["type"] = lease_types_long[lease.type]

    data["state"] = lease.binding_state
    data["ip"] = lease.ip

    try:
        data["pool"] = lease.sets[pool_key]
    except:
        data["pool"] = ""

    return data

def get_leases(config, leases, state, pool=None, sort='ip'):
    leases = IscDhcpLeases(lease_file).get()

    # filter leases by state
    if 'all' not in state:
        leases = list(filter(lambda x: x.binding_state in state, leases))

    # filter leases by pool name
    if pool is not None:
        if config.exists_effective("service dhcp-server shared-network-name {0}".format(pool)):
            leases = list(filter(lambda x: in_pool(x, pool), leases))
        else:
            print("Pool {0} does not exist.".format(pool))
            exit(0)

    # should maybe filter all state=active by lease.valid here?

    # sort by last_comm time to dedupe (newest lease overrides older)
    leases = sorted(leases, key = lambda lease: lease.last_communication)

    # dedupe by converting to dict
    leases_dict = {}
    for lease in leases:
        # dedupe by IP
        leases_dict[lease.ip] = lease

    # convert the lease data
    leases = list(map(get_lease_data, leases_dict.values()))

    # apply output/display sort
    if sort == 'ip':
        leases = sorted(leases, key = lambda k: int(ip_address(k['ip'].split('/')[0])))
    else:
        leases = sorted(leases, key = lambda k: k[sort])

    return leases

def show_leases(leases):
    lease_list = []
    for l in leases:
        lease_list_params = []
        for k in lease_display_fields.keys():
            lease_list_params.append(l[k])
        lease_list.append(lease_list_params)

    output = tabulate(lease_list, lease_display_fields.values())

    print(output)

if __name__ == '__main__':
    parser = ArgumentParser()

    group = parser.add_mutually_exclusive_group()
    group.add_argument("-l", "--leases", action="store_true", help="Show DHCPv6 leases")
    group.add_argument("-s", "--statistics", action="store_true", help="Show DHCPv6 statistics")
    group.add_argument("--allowed", type=str, choices=["pool", "sort", "state"], help="Show allowed values for argument")

    parser.add_argument("-p", "--pool", type=str, help="Show lease for specific pool")
    parser.add_argument("-S", "--sort", type=str, default='ip', help="Sort by")
    parser.add_argument("-t", "--state", type=str, nargs="+", default=["active"], help="Lease state to show (can specify multiple with spaces)")
    parser.add_argument("-j", "--json", action="store_true", default=False, help="Produce JSON output")

    args = parser.parse_args()

    conf = Config()

    if args.allowed == 'pool':
        if conf.exists_effective('service dhcpv6-server'):
            print(' '.join(conf.list_effective_nodes("service dhcpv6-server shared-network-name")))
        exit(0)
    elif args.allowed == 'sort':
        print(' '.join(lease_display_fields.keys()))
        exit(0)
    elif args.allowed == 'state':
        print(' '.join(lease_valid_states))
        exit(0)
    elif args.allowed:
        parser.print_help()
        exit(1)

    if args.sort not in lease_display_fields.keys():
        print(f'Invalid sort key, choose from: {list(lease_display_fields.keys())}')
        exit(0)

    if not set(args.state) < set(lease_valid_states):
            print(f'Invalid lease state, choose from: {lease_valid_states}')
            exit(0)

    # Do nothing if service is not configured
    if not conf.exists_effective('service dhcpv6-server'):
        print("DHCPv6 service is not configured")
        exit(0)

    # if dhcp server is down, inactive leases may still be shown as active, so warn the user.
    if call('systemctl -q is-active isc-dhcp-server6.service') != 0:
        print("WARNING: DHCPv6 server is configured but not started. Data may be stale.")

    if args.leases:
        leases = get_leases(conf, lease_file, args.state, args.pool, args.sort)

        if args.json:
            print(dumps(leases, indent=4))
        else:
            show_leases(leases)
    elif args.statistics:
        print("DHCPv6 statistics option is not available")
    else:
        parser.print_help()
        exit(1)