diff options
Diffstat (limited to 'src/conf_mode/interfaces_tunnel.py')
| -rwxr-xr-x | src/conf_mode/interfaces_tunnel.py | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/src/conf_mode/interfaces_tunnel.py b/src/conf_mode/interfaces_tunnel.py new file mode 100755 index 000000000..91aed9cc3 --- /dev/null +++ b/src/conf_mode/interfaces_tunnel.py @@ -0,0 +1,224 @@ +#!/usr/bin/env python3 +# +# Copyright (C) 2018-2022 yOS 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 netifaces import interfaces + +from vyos.config import Config +from vyos.configdict import get_interface_dict +from vyos.configdict import is_node_changed +from vyos.configverify import verify_address +from vyos.configverify import verify_bridge_delete +from vyos.configverify import verify_interface_exists +from vyos.configverify import verify_mtu_ipv6 +from vyos.configverify import verify_mirror_redirect +from vyos.configverify import verify_vrf +from vyos.configverify import verify_tunnel +from vyos.configverify import verify_bond_bridge_member +from vyos.ifconfig import Interface +from vyos.ifconfig import Section +from vyos.ifconfig import TunnelIf +from vyos.utils.network import get_interface_config +from vyos.utils.dict import dict_search +from vyos import ConfigError +from vyos import airbag +airbag.enable() + +def get_config(config=None): + """ + Retrive CLI config as dictionary. Dictionary can never be empty, as at least + the interface name will be added or a deleted flag + """ + if config: + conf = config + else: + conf = Config() + base = ['interfaces', 'tunnel'] + ifname, tunnel = get_interface_dict(conf, base) + + if 'deleted' not in tunnel: + tmp = is_node_changed(conf, base + [ifname, 'encapsulation']) + if tmp: tunnel.update({'encapsulation_changed': {}}) + + tmp = is_node_changed(conf, base + [ifname, 'parameters', 'ip', 'key']) + if tmp: tunnel.update({'key_changed': {}}) + + # We also need to inspect other configured tunnels as there are Kernel + # restrictions where we need to comply. E.g. GRE tunnel key can't be used + # twice, or with multiple GRE tunnels to the same location we must specify + # a GRE key + conf.set_level(base) + tunnel['other_tunnels'] = conf.get_config_dict([], key_mangling=('-', '_'), + get_first_key=True, + no_tag_node_value_mangle=True) + # delete our own instance from this dict + ifname = tunnel['ifname'] + del tunnel['other_tunnels'][ifname] + # if only one tunnel is present on the system, no need to keep this key + if len(tunnel['other_tunnels']) == 0: + del tunnel['other_tunnels'] + + # We must check if our interface is configured to be a DMVPN member + nhrp_base = ['protocols', 'nhrp', 'tunnel'] + conf.set_level(nhrp_base) + nhrp = conf.get_config_dict([], key_mangling=('-', '_'), get_first_key=True) + if nhrp: tunnel.update({'nhrp' : list(nhrp.keys())}) + + if 'encapsulation' in tunnel and tunnel['encapsulation'] not in ['erspan', 'ip6erspan']: + del tunnel['parameters']['erspan'] + + return tunnel + +def verify(tunnel): + if 'deleted' in tunnel: + verify_bridge_delete(tunnel) + + if 'nhrp' in tunnel and tunnel['ifname'] in tunnel['nhrp']: + raise ConfigError('Tunnel used for NHRP, it can not be deleted!') + + return None + + verify_tunnel(tunnel) + + if tunnel['encapsulation'] in ['erspan', 'ip6erspan']: + if dict_search('parameters.ip.key', tunnel) == None: + raise ConfigError('ERSPAN requires ip key parameter!') + + # this is a default field + ver = int(tunnel['parameters']['erspan']['version']) + if ver == 1: + if 'hw_id' in tunnel['parameters']['erspan']: + raise ConfigError('ERSPAN version 1 does not support hw-id!') + if 'direction' in tunnel['parameters']['erspan']: + raise ConfigError('ERSPAN version 1 does not support direction!') + elif ver == 2: + if 'idx' in tunnel['parameters']['erspan']: + raise ConfigError('ERSPAN version 2 does not index parameter!') + if 'direction' not in tunnel['parameters']['erspan']: + raise ConfigError('ERSPAN version 2 requires direction to be set!') + + # If tunnel source is any and gre key is not set + interface = tunnel['ifname'] + if tunnel['encapsulation'] in ['gre'] and \ + dict_search('source_address', tunnel) == '0.0.0.0' and \ + dict_search('parameters.ip.key', tunnel) == None: + raise ConfigError(f'"parameters ip key" must be set for {interface} when '\ + 'encapsulation is GRE!') + + gre_encapsulations = ['gre', 'gretap'] + if tunnel['encapsulation'] in gre_encapsulations and 'other_tunnels' in tunnel: + # Check pairs tunnel source-address/encapsulation/key with exists tunnels. + # Prevent the same key for 2 tunnels with same source-address/encap. T2920 + for o_tunnel, o_tunnel_conf in tunnel['other_tunnels'].items(): + # no match on encapsulation - bail out + our_encapsulation = tunnel['encapsulation'] + their_encapsulation = o_tunnel_conf['encapsulation'] + if our_encapsulation in gre_encapsulations and their_encapsulation \ + not in gre_encapsulations: + continue + + our_address = dict_search('source_address', tunnel) + our_key = dict_search('parameters.ip.key', tunnel) + their_address = dict_search('source_address', o_tunnel_conf) + their_key = dict_search('parameters.ip.key', o_tunnel_conf) + if our_key != None: + if their_address == our_address and their_key == our_key: + raise ConfigError(f'Key "{our_key}" for source-address "{our_address}" ' \ + f'is already used for tunnel "{o_tunnel}"!') + else: + our_source_if = dict_search('source_interface', tunnel) + their_source_if = dict_search('source_interface', o_tunnel_conf) + our_remote = dict_search('remote', tunnel) + their_remote = dict_search('remote', o_tunnel_conf) + # If no IP GRE key is defined we can not have more then one GRE tunnel + # bound to any one interface/IP address and the same remote. This will + # result in a OS PermissionError: add tunnel "gre0" failed: File exists + if (their_address == our_address or our_source_if == their_source_if) and \ + our_remote == their_remote: + raise ConfigError(f'Missing required "ip key" parameter when '\ + 'running more then one GRE based tunnel on the '\ + 'same source-interface/source-address') + + # Keys are not allowed with ipip and sit tunnels + if tunnel['encapsulation'] in ['ipip', 'sit']: + if dict_search('parameters.ip.key', tunnel) != None: + raise ConfigError('Keys are not allowed with ipip and sit tunnels!') + + verify_mtu_ipv6(tunnel) + verify_address(tunnel) + verify_vrf(tunnel) + verify_bond_bridge_member(tunnel) + verify_mirror_redirect(tunnel) + + if 'source_interface' in tunnel: + verify_interface_exists(tunnel['source_interface']) + + # TTL != 0 and nopmtudisc are incompatible, parameters and ip use default + # values, thus the keys are always present. + if dict_search('parameters.ip.no_pmtu_discovery', tunnel) != None: + if dict_search('parameters.ip.ttl', tunnel) != '0': + raise ConfigError('Disabled PMTU requires TTL set to "0"!') + if tunnel['encapsulation'] in ['ipip6', 'ip6ip6', 'ip6gre']: + raise ConfigError('Can not disable PMTU discovery for given encapsulation') + + if dict_search('parameters.ip.ignore_df', tunnel) != None: + if tunnel['encapsulation'] not in ['gretap']: + raise ConfigError('Option ignore-df can only be used on GRETAP tunnels!') + + if dict_search('parameters.ip.no_pmtu_discovery', tunnel) == None: + raise ConfigError('Option ignore-df requires path MTU discovery to be disabled!') + + +def generate(tunnel): + return None + +def apply(tunnel): + interface = tunnel['ifname'] + # If a gretap tunnel is already existing we can not "simply" change local or + # remote addresses. This returns "Operation not supported" by the Kernel. + # There is no other solution to destroy and recreate the tunnel. + encap = '' + remote = '' + tmp = get_interface_config(interface) + if tmp: + encap = dict_search('linkinfo.info_kind', tmp) + remote = dict_search('linkinfo.info_data.remote', tmp) + + if ('deleted' in tunnel or 'encapsulation_changed' in tunnel or encap in + ['gretap', 'ip6gretap', 'erspan', 'ip6erspan'] or remote in ['any'] or + 'key_changed' in tunnel): + if interface in interfaces(): + tmp = Interface(interface) + tmp.remove() + if 'deleted' in tunnel: + return None + + tun = TunnelIf(**tunnel) + tun.update(tunnel) + + return None + +if __name__ == '__main__': + try: + c = get_config() + generate(c) + verify(c) + apply(c) + except ConfigError as e: + print(e) + exit(1) |