summaryrefslogtreecommitdiff
path: root/src/conf_mode/tftp_server.py
blob: ff7cad0c9ad23363a6c98de9d7db4edd126f43d7 (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
#!/usr/bin/env python3
#
# Copyright (C) 2018 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 sys
import os
import stat
import pwd
import copy
import glob

import jinja2
import vyos.validate

from vyos.config import Config
from vyos import ConfigError

config_file = r'/etc/default/tftpd'

# Please be careful if you edit the template.
config_tmpl = """
### Autogenerated by tftp_server.py ###
DAEMON_ARGS="--listen --user tftp --address {% for a in listen-%}{{ a }}{% endfor %}{% if allow_upload %} --create --umask 000{% endif %} --secure {{ directory }}"


"""

default_config_data = {
    'directory': '',
    'allow_upload': False,
    'port': '69',
    'listen': []
}

def get_config():
    tftpd = copy.deepcopy(default_config_data)
    conf = Config()
    if not conf.exists('service tftp-server'):
        return None
    else:
        conf.set_level('service tftp-server')

    if conf.exists('directory'):
        tftpd['directory'] = conf.return_value('directory')

    if conf.exists('allow-upload'):
        tftpd['allow_upload'] = True

    if conf.exists('port'):
        tftpd['port'] = conf.return_value('port')

    tftpd['listen'] = conf.return_values('listen-address')

    return tftpd

def verify(tftpd):
    # bail out early - looks like removal from running config
    if tftpd is None:
        return None

    # Configuring allowed clients without a server makes no sense
    if not tftpd['directory']:
        raise ConfigError('TFTP root directory must be configured!')

    if not tftpd['listen']:
        raise ConfigError('TFTP server listen address must be configured!')

    for addr in tftpd['listen']:
        if not vyos.validate.is_addr_assigned(addr):
            print('WARNING: TFTP server listen address {0} not assigned to any interface!'.format(addr))

    return None

def generate(tftpd):
    # cleanup any available configuration file
    # files will be recreated on demand
    for i in glob.glob(config_file + '*'):
        os.unlink(i)

    # bail out early - looks like removal from running config
    if tftpd is None:
        return None

    idx = 0
    for listen in tftpd['listen']:
        config = copy.deepcopy(tftpd)
        if vyos.validate.is_ipv4(listen):
            config['listen'] = [listen + ":" + tftpd['port'] + " -4"]
        else:
            config['listen'] = ["[" + listen + "]" + tftpd['port'] + " -6"]

        tmpl = jinja2.Template(config_tmpl)
        config_text = tmpl.render(config)
        file = config_file + str(idx)
        with open(file, 'w') as f:
            f.write(config_text)

        idx = idx + 1

    return None

def apply(tftpd):
    # stop all services first - then we will decide
    os.system('sudo systemctl stop tftpd@{0..20}')

    # bail out early - e.g. service deletion
    if tftpd is None:
        return None

    tftp_root = tftpd['directory']
    if not os.path.exists(tftp_root):
        os.makedirs(tftp_root)
        os.chmod(tftp_root, stat.S_IRUSR|stat.S_IWUSR|stat.S_IXUSR|stat.S_IRGRP|stat.S_IXGRP|stat.S_IROTH|stat.S_IXOTH)

    # get UNIX uid for user 'tftp'
    tftp_uid = pwd.getpwnam('tftp').pw_uid
    tftp_gid = pwd.getpwnam('tftp').pw_gid

    # get UNIX uid for tftproot directory
    dir_uid = os.stat(tftp_root).st_uid
    dir_gid = os.stat(tftp_root).st_gid

    # adjust uid/gid of tftproot directory if files don't belong to user tftp
    if (tftp_uid != dir_uid) or (tftp_gid != dir_gid):
        os.chown(tftp_root, tftp_uid, tftp_gid)

    idx = 0
    for listen in tftpd['listen']:
        os.system('sudo systemctl restart tftpd@{0}.service'.format(idx))
        idx = idx + 1

    return None

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