# Copyright 2019 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/>. """ A library for retrieving value dicts from VyOS configs in a declarative fashion. """ from enum import Enum from copy import deepcopy from vyos import ConfigError from vyos.ifconfig import Interface from vyos.validate import is_member from vyos.util import ifname_from_config def retrieve_config(path_hash, base_path, config): """ Retrieves a VyOS config as a dict according to a declarative description The description dict, passed in the first argument, must follow this format: ``field_name : <path, type, [inner_options_dict]>``. Supported types are: ``str`` (for normal nodes), ``list`` (returns a list of strings, for multi nodes), ``bool`` (returns True if valueless node exists), ``dict`` (for tag nodes, returns a dict indexed by node names, according to description in the third item of the tuple). Args: path_hash (dict): Declarative description of the config to retrieve base_path (list): A base path to prepend to all option paths config (vyos.config.Config): A VyOS config object Returns: dict: config dict """ config_hash = {} for k in path_hash: if type(path_hash[k]) != tuple: raise ValueError("In field {0}: expected a tuple, got a value {1}".format(k, str(path_hash[k]))) if len(path_hash[k]) < 2: raise ValueError("In field {0}: field description must be a tuple of at least two items, path (list) and type".format(k)) path = path_hash[k][0] if type(path) != list: raise ValueError("In field {0}: path must be a list, not a {1}".format(k, type(path))) typ = path_hash[k][1] if type(typ) != type: raise ValueError("In field {0}: type must be a type, not a {1}".format(k, type(typ))) path = base_path + path path_str = " ".join(path) if typ == str: config_hash[k] = config.return_value(path_str) elif typ == list: config_hash[k] = config.return_values(path_str) elif typ == bool: config_hash[k] = config.exists(path_str) elif typ == dict: try: inner_hash = path_hash[k][2] except IndexError: raise ValueError("The type of the \'{0}\' field is dict, but inner options hash is missing from the tuple".format(k)) config_hash[k] = {} nodes = config.list_nodes(path_str) for node in nodes: config_hash[k][node] = retrieve_config(inner_hash, path + [node], config) return config_hash def list_diff(first, second): """ Diff two dictionaries and return only unique items """ second = set(second) return [item for item in first if item not in second] def get_ethertype(ethertype_val): if ethertype_val == '0x88A8': return '802.1ad' elif ethertype_val == '0x8100': return '802.1q' else: raise ConfigError('invalid ethertype "{}"'.format(ethertype_val)) vlan_default = { 'address': [], 'address_remove': [], 'description': '', 'dhcp_client_id': '', 'dhcp_hostname': '', 'dhcp_vendor_class_id': '', 'dhcpv6_prm_only': False, 'dhcpv6_temporary': False, 'disable': False, 'disable_link_detect': 1, 'egress_qos': '', 'egress_qos_changed': False, 'ip_disable_arp_filter': 1, 'ip_enable_arp_accept': 0, 'ip_enable_arp_announce': 0, 'ip_enable_arp_ignore': 0, 'ip_proxy_arp': 0, 'ipv6_accept_ra': 1, 'ipv6_autoconf': 0, 'ipv6_eui64_prefix': [], 'ipv6_eui64_prefix_remove': [], 'ipv6_forwarding': 1, 'ipv6_dup_addr_detect': 1, 'ingress_qos': '', 'ingress_qos_changed': False, 'is_bridge_member': False, 'mac': '', 'mtu': 1500, 'vif_c': {}, 'vif_c_remove': [], 'vrf': '' } # see: https://docs.python.org/3/library/enum.html#functional-api disable = Enum('disable','none was now both') def disable_state(conf, check=[3,5,7]): """ return if and how a particual section of the configuration is has disable'd using "disable" including if it was disabled by one of its parent. check: a list of the level we should check, here 7,5 and 3 interfaces ethernet eth1 vif-s 1 vif-c 2 disable interfaces ethernet eth1 vif 1 disable interfaces ethernet eth1 disable it returns an enum (none, was, now, both) """ # save where we are in the config current_level = conf.get_level() # logic to figure out if the interface (or one of it parent is disabled) eff_disable = False act_disable = False levels = check[:] working_level = current_level[:] while levels: position = len(working_level) if not position: break if position not in levels: working_level = working_level[:-1] continue levels.remove(position) conf.set_level(working_level) working_level = working_level[:-1] eff_disable = eff_disable or conf.exists_effective('disable') act_disable = act_disable or conf.exists('disable') conf.set_level(current_level) # how the disabling changed if eff_disable and act_disable: return disable.both if eff_disable and not eff_disable: return disable.was if not eff_disable and act_disable: return disable.now return disable.none def intf_to_dict(conf, default): """ Common used function which will extract VLAN related information from config and represent the result as Python dictionary. Function call's itself recursively if a vif-s/vif-c pair is detected. """ intf = deepcopy(default) intf['intf'] = ifname_from_config(conf) # retrieve interface description if conf.exists('description'): intf['description'] = conf.return_value('description') # get DHCP client identifier if conf.exists('dhcp-options client-id'): intf['dhcp_client_id'] = conf.return_value('dhcp-options client-id') # DHCP client host name (overrides the system host name) if conf.exists('dhcp-options host-name'): intf['dhcp_hostname'] = conf.return_value('dhcp-options host-name') # DHCP client vendor identifier if conf.exists('dhcp-options vendor-class-id'): intf['dhcp_vendor_class_id'] = conf.return_value( 'dhcp-options vendor-class-id') # DHCPv6 only acquire config parameters, no address if conf.exists('dhcpv6-options parameters-only'): intf['dhcpv6_prm_only'] = True # DHCPv6 temporary IPv6 address if conf.exists('dhcpv6-options temporary'): intf['dhcpv6_temporary'] = True # ignore link state changes if conf.exists('disable-link-detect'): intf['disable_link_detect'] = 2 # ARP filter configuration if conf.exists('ip disable-arp-filter'): intf['ip_disable_arp_filter'] = 0 # ARP enable accept if conf.exists('ip enable-arp-accept'): intf['ip_enable_arp_accept'] = 1 # ARP enable announce if conf.exists('ip enable-arp-announce'): intf['ip_enable_arp_announce'] = 1 # ARP enable ignore if conf.exists('ip enable-arp-ignore'): intf['ip_enable_arp_ignore'] = 1 # Enable Proxy ARP if conf.exists('ip enable-proxy-arp'): intf['ip_proxy_arp'] = 1 # Enable acquisition of IPv6 address using stateless autoconfig (SLAAC) if conf.exists('ipv6 address autoconf'): intf['ipv6_autoconf'] = 1 # Disable IPv6 forwarding on this interface if conf.exists('ipv6 disable-forwarding'): intf['ipv6_forwarding'] = 0 # check if interface is member of a bridge intf['is_bridge_member'] = is_member(conf, intf['intf'], 'bridge') # IPv6 Duplicate Address Detection (DAD) tries if conf.exists('ipv6 dup-addr-detect-transmits'): intf['ipv6_dup_addr_detect'] = int( conf.return_value('ipv6 dup-addr-detect-transmits')) # Media Access Control (MAC) address if conf.exists('mac'): intf['mac'] = conf.return_value('mac') # Maximum Transmission Unit (MTU) if conf.exists('mtu'): intf['mtu'] = int(conf.return_value('mtu')) # retrieve VRF instance if conf.exists('vrf'): intf['vrf'] = conf.return_value('vrf') # egress QoS if conf.exists('egress-qos'): intf['egress_qos'] = conf.return_value('egress-qos') # egress changes QoS require VLAN interface recreation if conf.return_effective_value('egress-qos'): if intf['egress_qos'] != conf.return_effective_value('egress-qos'): intf['egress_qos_changed'] = True # ingress QoS if conf.exists('ingress-qos'): intf['ingress_qos'] = conf.return_value('ingress-qos') # ingress changes QoS require VLAN interface recreation if conf.return_effective_value('ingress-qos'): if intf['ingress_qos'] != conf.return_effective_value('ingress-qos'): intf['ingress_qos_changed'] = True # Get the interface addresses intf['address'] = conf.return_values('address') # addresses to remove - difference between effective and working config intf['address_remove'] = list_diff( conf.return_effective_values('address'), intf['address'] ) # Get prefixes for IPv6 addressing based on MAC address (EUI-64) intf['ipv6_eui64_prefix'] = conf.return_values('ipv6 address eui64') # EUI64 to remove - difference between effective and working config intf['ipv6_eui64_prefix_remove'] = list_diff( conf.return_effective_values('ipv6 address eui64'), intf['ipv6_eui64_prefix'] ) # Determine if the interface should be disabled disabled = disable_state(conf) if disabled == disable.both: # was and is still disabled intf['disable'] = True elif disabled == disable.now: # it is now disable but was not before intf['disable'] = True elif disabled == disable.was: # it was disable but not anymore intf['disable'] = False else: # normal change intf['disable'] = False # Remove the default link-local address if no-default-link-local is set, # if member of a bridge or if disabled (it may not have a MAC if it's down) if ( conf.exists('ipv6 address no-default-link-local') or intf.get('is_bridge_member') or intf['disable'] ): intf['ipv6_eui64_prefix_remove'].append('fe80::/64') else: # add the link-local by default to make IPv6 work intf['ipv6_eui64_prefix'].append('fe80::/64') # If MAC has changed, remove and re-add all IPv6 EUI64 addresses try: interface = Interface(intf['intf'], create=False) if intf['mac'] and intf['mac'] != interface.get_mac(): intf['ipv6_eui64_prefix_remove'] += intf['ipv6_eui64_prefix'] except Exception: # If the interface does not exist, it could not have changed pass # to make IPv6 SLAAC and DHCPv6 work with forwarding=1, # accept_ra must be 2 if intf['ipv6_autoconf'] or 'dhcpv6' in intf['address']: intf['ipv6_accept_ra'] = 2 return intf, disable def add_to_dict(conf, disabled, ifdict, section, key): """ parse a section of vif/vif-s/vif-c and add them to the dict follow the convention to: * use the "key" for what to add * use the "key" what what to remove conf: is the Config() already at the level we need to parse disabled: is a disable enum so we know how to handle to data intf: if the interface dictionary section: is the section name to parse (vif/vif-s/vif-c) key: is the dict key to use (vif/vifs/vifc) """ if not conf.exists(section): return ifdict effect = conf.list_effective_nodes(section) active = conf.list_nodes(section) # the section to parse for vlan sections = [] # determine which interfaces to add or remove based on disable state if disabled == disable.both: # was and is still disabled ifdict[f'{key}_remove'] = [] elif disabled == disable.now: # it is now disable but was not before ifdict[f'{key}_remove'] = effect elif disabled == disable.was: # it was disable but not anymore ifdict[f'{key}_remove'] = [] sections = active else: # normal change # get interfaces (currently effective) - to determine which # interface is no longer present and needs to be removed ifdict[f'{key}_remove'] = list_diff(effect, active) sections = active current_level = conf.get_level() # add each section, the key must already exists for s in sections: # set config level to vif interface conf.set_level(current_level + [section, s]) # add the vlan config as a key (vlan id) - value (config) pair ifdict[key][s] = vlan_to_dict(conf) # re-set configuration level to leave things as found conf.set_level(current_level) return ifdict def vlan_to_dict(conf, default=vlan_default): vlan, disabled = intf_to_dict(conf, default) # if this is a not within vif-s node, we are done if conf.get_level()[-2] != 'vif-s': return vlan # ethertype is mandatory on vif-s nodes and only exists here! # ethertype uses a default of 0x88A8 tmp = '0x88A8' if conf.exists('ethertype'): tmp = conf.return_value('ethertype') vlan['ethertype'] = get_ethertype(tmp) # check if there is a Q-in-Q vlan customer interface # and call this function recursively add_to_dict(conf, disable, vlan, 'vif-c', 'vif_c') return vlan