summaryrefslogtreecommitdiff
path: root/src/conf_mode/protocols_mpls.py
blob: 7f46e1218dd6cc039694534dd6bf01b4edd379b4 (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
#!/usr/bin/env python3
#
# Copyright (C) 2020-2022 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

from sys import exit

from glob import glob
from vyos.config import Config
from vyos.template import render_to_string
from vyos.util import dict_search
from vyos.util import read_file
from vyos.util import sysctl_write
from vyos import ConfigError
from vyos import frr
from vyos import airbag
airbag.enable()

config_file = r'/tmp/ldpd.frr'

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

    mpls = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)
    return mpls

def verify(mpls):
    # If no config, then just bail out early.
    if not mpls:
        return None

    # Checks to see if LDP is properly configured
    if 'ldp' in mpls:
        # If router ID not defined
        if 'router_id' not in mpls['ldp']:
            raise ConfigError('Router ID missing. An LDP router id is mandatory!')

        # If interface not set
        if 'interface' not in mpls['ldp']:
            raise ConfigError('LDP interfaces are missing. An LDP interface is mandatory!')

        # If transport addresses are not set
        if not dict_search('ldp.discovery.transport_ipv4_address', mpls) and \
           not dict_search('ldp.discovery.transport_ipv6_address', mpls):
                raise ConfigError('LDP transport address missing!')

    return None

def generate(mpls):
    # If there's no MPLS config generated, create dictionary key with no value.
    if not mpls:
        mpls['new_frr_config'] = ''
        return None

    mpls['new_frr_config'] = render_to_string('frr/ldpd.frr.tmpl', mpls)
    return None

def apply(mpls):
    ldpd_damon = 'ldpd'
    # Save original configuration prior to starting any commit actions
    frr_cfg = frr.FRRConfig()

    frr_cfg.load_configuration(ldpd_damon)
    frr_cfg.modify_section(f'^mpls ldp')
    frr_cfg.add_before(r'(ip prefix-list .*|route-map .*|line vty|end)', mpls['new_frr_config'])
    for x in range(3):
        frr_cfg.commit_configuration(ldpd_damon)

    # Set number of entries in the platform label tables
    labels = '0'
    if 'interface' in mpls:
        labels = '1048575'
    sysctl_write('net.mpls.platform_labels', labels)

    # Check for changes in global MPLS options
    if 'parameters' in mpls:
            # Choose whether to copy IP TTL to MPLS header TTL
        if 'no_propagate_ttl' in mpls['parameters']:
            sysctl_write('net.mpls.ip_ttl_propagate', 0)
            # Choose whether to limit maximum MPLS header TTL
        if 'maximum_ttl' in mpls['parameters']:
            ttl = mpls['parameters']['maximum_ttl']
            sysctl_write('net.mpls.default_ttl', ttl)
    else:
        # Set default global MPLS options if not defined.
        sysctl_write('net.mpls.ip_ttl_propagate', 1)
        sysctl_write('net.mpls.default_ttl', 255)

    # Enable and disable MPLS processing on interfaces per configuration
    if 'interface' in mpls:
        system_interfaces = []
        # Populate system interfaces list with local MPLS capable interfaces
        for interface in glob('/proc/sys/net/mpls/conf/*'):
            system_interfaces.append(os.path.basename(interface))   
        # This is where the comparison is done on if an interface needs to be enabled/disabled.
        for system_interface in system_interfaces:
            interface_state = read_file(f'/proc/sys/net/mpls/conf/{system_interface}/input')
            if '1' in interface_state:
                if system_interface not in mpls['interface']:
                    system_interface = system_interface.replace('.', '/')
                    sysctl_write(f'net.mpls.conf.{system_interface}.input', 0)
            elif '0' in interface_state:
                if system_interface in mpls['interface']:
                    system_interface = system_interface.replace('.', '/')
                    sysctl_write(f'net.mpls.conf.{system_interface}.input', 1)
    else:
        system_interfaces = []
        # If MPLS interfaces are not configured, set MPLS processing disabled
        for interface in glob('/proc/sys/net/mpls/conf/*'):
            system_interfaces.append(os.path.basename(interface)) 
        for system_interface in system_interfaces:
            system_interface = system_interface.replace('.', '/')
            sysctl_write(f'net.mpls.conf.{system_interface}.input', 0)

    return None

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