diff options
Diffstat (limited to 'python/vyos/configdict.py')
| -rw-r--r-- | python/vyos/configdict.py | 314 |
1 files changed, 314 insertions, 0 deletions
diff --git a/python/vyos/configdict.py b/python/vyos/configdict.py new file mode 100644 index 000000000..bd8624ced --- /dev/null +++ b/python/vyos/configdict.py @@ -0,0 +1,314 @@ +# 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. +""" +import os + +from enum import Enum +from copy import deepcopy + +from vyos import ConfigError + +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 dict_merge(source, destination): + """ Merge two dictionaries. Only keys which are not present in destination + will be copied from source, anything else will be kept untouched. Function + will return a new dict which has the merged key/value pairs. """ + from copy import deepcopy + tmp = deepcopy(destination) + + for key, value in source.items(): + if key not in tmp: + tmp[key] = value + elif isinstance(source[key], dict): + tmp[key] = dict_merge(source[key], tmp[key]) + + return tmp + +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 T2665_default_dict_cleanup(dict): + """ Cleanup default keys for tag nodes https://phabricator.vyos.net/T2665. """ + # Cleanup + for vif in ['vif', 'vif_s']: + if vif in dict: + for key in ['ip', 'mtu', 'dhcpv6_options']: + if key in dict[vif]: + del dict[vif][key] + + # cleanup VIF-S defaults + if 'vif_c' in dict[vif]: + for key in ['ip', 'mtu', 'dhcpv6_options']: + if key in dict[vif]['vif_c']: + del dict[vif]['vif_c'][key] + # If there is no vif-c defined and we just cleaned the default + # keys - we can clean the entire vif-c dict as it's useless + if not dict[vif]['vif_c']: + del dict[vif]['vif_c'] + + # If there is no real vif/vif-s defined and we just cleaned the default + # keys - we can clean the entire vif dict as it's useless + if not dict[vif]: + del dict[vif] + + if 'dhcpv6_options' in dict and 'pd' in dict['dhcpv6_options']: + if 'length' in dict['dhcpv6_options']['pd']: + del dict['dhcpv6_options']['pd']['length'] + + # delete empty dicts + if 'dhcpv6_options' in dict: + if 'pd' in dict['dhcpv6_options']: + # test if 'pd' is an empty node so we can remove it + if not dict['dhcpv6_options']['pd']: + del dict['dhcpv6_options']['pd'] + + # test if 'dhcpv6_options' is an empty node so we can remove it + if not dict['dhcpv6_options']: + del dict['dhcpv6_options'] + + return dict + +def leaf_node_changed(conf, path): + """ + Check if a leaf node was altered. If it has been altered - values has been + changed, or it was added/removed, we will return the old value. If nothing + has been changed, None is returned + """ + from vyos.configdiff import get_config_diff + D = get_config_diff(conf, key_mangling=('-', '_')) + D.set_level(conf.get_level()) + (new, old) = D.get_value_diff(path) + if new != old: + if isinstance(old, str): + return old + elif isinstance(old, list): + if isinstance(new, str): + new = [new] + elif isinstance(new, type(None)): + new = [] + return list_diff(old, new) + + return None + +def node_changed(conf, path): + """ + Check if a leaf node was altered. If it has been altered - values has been + changed, or it was added/removed, we will return the old value. If nothing + has been changed, None is returned + """ + from vyos.configdiff import get_config_diff, Diff + D = get_config_diff(conf, key_mangling=('-', '_')) + D.set_level(conf.get_level()) + # get_child_nodes() will return dict_keys(), mangle this into a list with PEP448 + keys = D.get_child_nodes_diff(path, expand_nodes=Diff.DELETE)['delete'].keys() + return list(keys) + +def get_removed_vlans(conf, dict): + """ + Common function to parse a dictionary retrieved via get_config_dict() and + determine any added/removed VLAN interfaces - be it 802.1q or Q-in-Q. + """ + from vyos.configdiff import get_config_diff, Diff + + # Check vif, vif-s/vif-c VLAN interfaces for removal + D = get_config_diff(conf, key_mangling=('-', '_')) + D.set_level(conf.get_level()) + # get_child_nodes() will return dict_keys(), mangle this into a list with PEP448 + keys = D.get_child_nodes_diff(['vif'], expand_nodes=Diff.DELETE)['delete'].keys() + if keys: + dict.update({'vif_remove': [*keys]}) + + # get_child_nodes() will return dict_keys(), mangle this into a list with PEP448 + keys = D.get_child_nodes_diff(['vif-s'], expand_nodes=Diff.DELETE)['delete'].keys() + if keys: + dict.update({'vif_s_remove': [*keys]}) + + for vif in dict.get('vif_s', {}).keys(): + keys = D.get_child_nodes_diff(['vif-s', vif, 'vif-c'], expand_nodes=Diff.DELETE)['delete'].keys() + if keys: + dict.update({'vif_s': { vif : {'vif_c_remove': [*keys]}}}) + + return dict + + +def dict_add_dhcpv6pd_defaults(defaults, config_dict): + # Implant default dictionary for DHCPv6-PD instances + if 'dhcpv6_options' in config_dict and 'pd' in config_dict['dhcpv6_options']: + for pd, pd_config in config_dict['dhcpv6_options']['pd'].items(): + config_dict['dhcpv6_options']['pd'][pd] = dict_merge( + defaults, pd_config) + + return config_dict + +def get_interface_dict(config, base, ifname=''): + """ + Common utility function to retrieve and mandgle the interfaces available + in CLI configuration. All interfaces have a common base ground where the + value retrival is identical - so it can and should be reused + + Will return a dictionary with the necessary interface configuration + """ + from vyos.util import vyos_dict_search + from vyos.validate import is_member + from vyos.xml import defaults + + if not ifname: + # determine tagNode instance + if 'VYOS_TAGNODE_VALUE' not in os.environ: + raise ConfigError('Interface (VYOS_TAGNODE_VALUE) not specified') + ifname = os.environ['VYOS_TAGNODE_VALUE'] + + # retrieve interface default values + default_values = defaults(base) + + # setup config level which is extracted in get_removed_vlans() + config.set_level(base + [ifname]) + dict = config.get_config_dict([], key_mangling=('-', '_'), get_first_key=True) + + # Check if interface has been removed + if dict == {}: + dict.update({'deleted' : ''}) + + # Add interface instance name into dictionary + dict.update({'ifname': ifname}) + + # We have gathered the dict representation of the CLI, but there are + # default options which we need to update into the dictionary + # retrived. + dict = dict_merge(default_values, dict) + + # Check if we are a member of a bridge device + bridge = is_member(config, ifname, 'bridge') + if bridge: + dict.update({'is_bridge_member' : bridge}) + + # Check if we are a member of a bond device + bond = is_member(config, ifname, 'bonding') + if bond: + dict.update({'is_bond_member' : bond}) + + mac = leaf_node_changed(config, ['mac']) + if mac: + dict.update({'mac_old' : mac}) + + eui64 = leaf_node_changed(config, ['ipv6', 'address', 'eui64']) + if eui64: + # XXX: T2636 workaround: convert string to a list with one element + if isinstance(eui64, str): + eui64 = [eui64] + tmp = vyos_dict_search('ipv6.address', dict) + if not tmp: + dict.update({'ipv6': {'address': {'eui64_old': eui64}}}) + else: + dict['ipv6']['address'].update({'eui64_old': eui64}) + + # remove wrongly inserted values + dict = T2665_default_dict_cleanup(dict) + + # Implant default dictionary for DHCPv6-PD instances + default_pd_values = defaults(base + ['dhcpv6-options', 'pd']) + dict = dict_add_dhcpv6pd_defaults(default_pd_values, dict) + + # Implant default dictionary in vif/vif-s VLAN interfaces. Values are + # identical for all types of VLAN interfaces as they all include the same + # XML definitions which hold the defaults. + default_vif_values = defaults(base + ['vif']) + for vif, vif_config in dict.get('vif', {}).items(): + dict['vif'][vif] = dict_add_dhcpv6pd_defaults( + default_pd_values, vif_config) + dict['vif'][vif] = T2665_default_dict_cleanup( + dict_merge(default_vif_values, vif_config)) + + for vif_s, vif_s_config in dict.get('vif_s', {}).items(): + dict['vif_s'][vif_s] = dict_add_dhcpv6pd_defaults( + default_pd_values, vif_s_config) + dict['vif_s'][vif_s] = T2665_default_dict_cleanup( + dict_merge(default_vif_values, vif_s_config)) + for vif_c, vif_c_config in vif_s_config.get('vif_c', {}).items(): + dict['vif_s'][vif_s]['vif_c'][vif_c] = dict_add_dhcpv6pd_defaults( + default_pd_values, vif_c_config) + dict['vif_s'][vif_s]['vif_c'][vif_c] = T2665_default_dict_cleanup( + dict_merge(default_vif_values, vif_c_config)) + + # Check vif, vif-s/vif-c VLAN interfaces for removal + dict = get_removed_vlans(config, dict) + + return dict + |