#!/usr/bin/env python3 # # Copyright (C) 2018-2020 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 import re from sys import exit import ipaddress from ipaddress import ip_address from jinja2 import FileSystemLoader, Environment from vyos.ifconfig import Section from vyos.ifconfig import Interface from vyos.config import Config from vyos import ConfigError from vyos.util import cmd from vyos.template import render # default values default_sflow_server_port = 6343 default_netflow_server_port = 2055 default_plugin_pipe_size = 10 default_captured_packet_size = 128 default_netflow_version = '9' default_sflow_agentip = 'auto' uacctd_conf_path = '/etc/pmacct/uacctd.conf' iptables_nflog_table = 'raw' iptables_nflog_chain = 'VYATTA_CT_PREROUTING_HOOK' # helper functions # check if node exists and return True if this is true def _node_exists(path): vyos_config = Config() if vyos_config.exists(path): return True # get sFlow agent-ip if agent-address is "auto" (default behaviour) def _sflow_default_agentip(config): # check if any of BGP, OSPF, OSPFv3 protocols are configured and use router-id from there if config.exists('protocols bgp'): bgp_router_id = config.return_value("protocols bgp {} parameters router-id".format(config.list_nodes('protocols bgp')[0])) if bgp_router_id: return bgp_router_id if config.return_value('protocols ospf parameters router-id'): return config.return_value('protocols ospf parameters router-id') if config.return_value('protocols ospfv3 parameters router-id'): return config.return_value('protocols ospfv3 parameters router-id') # if router-id was not found, use first available ip of any interface for iface in Section.interfaces(): for address in Interface(iface).get_addr(): # return an IP, if this is not loopback regex_filter = re.compile('^(?!(127)|(::1)|(fe80))(?P<ipaddr>[a-f\d\.:]+)/\d+$') if regex_filter.search(address): return regex_filter.search(address).group('ipaddr') # return nothing by default return None # get iptables rule dict for chain in table def _iptables_get_nflog(): # define list with rules rules = [] # prepare regex for parsing rules rule_pattern = "^-A (?P<rule_definition>{0} -i (?P<interface>[\w\.\*\-]+).*--comment FLOW_ACCOUNTING_RULE.* -j NFLOG.*$)".format(iptables_nflog_chain) rule_re = re.compile(rule_pattern) for iptables_variant in ['iptables', 'ip6tables']: # run iptables, save output and split it by lines iptables_command = "sudo {0} -t {1} -S {2}".format(iptables_variant, iptables_nflog_table, iptables_nflog_chain) tmp = cmd(iptables_command, message='Failed to get flows list') # parse each line and add information to list for current_rule in tmp.splitlines(): current_rule_parsed = rule_re.search(current_rule) if current_rule_parsed: rules.append({ 'interface': current_rule_parsed.groupdict()["interface"], 'iptables_variant': iptables_variant, 'table': iptables_nflog_table, 'rule_definition': current_rule_parsed.groupdict()["rule_definition"] }) # return list with rules return rules # modify iptables rules def _iptables_config(configured_ifaces): # define list of iptables commands to modify settings iptable_commands = [] # prepare extended list with configured interfaces configured_ifaces_extended = [] for iface in configured_ifaces: configured_ifaces_extended.append({ 'iface': iface, 'iptables_variant': 'iptables' }) configured_ifaces_extended.append({ 'iface': iface, 'iptables_variant': 'ip6tables' }) # get currently configured interfaces with iptables rules active_nflog_rules = _iptables_get_nflog() # compare current active list with configured one and delete excessive interfaces, add missed active_nflog_ifaces = [] for rule in active_nflog_rules: iptables = rule['iptables_variant'] interface = rule['interface'] if interface not in configured_ifaces: table = rule['table'] rule = rule['rule_definition'] iptable_commands.append(f'sudo {iptables} -t {table} -D {rule}') else: active_nflog_ifaces.append({ 'iface': interface, 'iptables_variant': iptables, }) # do not create new rules for already configured interfaces for iface in active_nflog_ifaces: if iface in active_nflog_ifaces: configured_ifaces_extended.remove(iface) # create missed rules for iface_extended in configured_ifaces_extended: iface = iface_extended['iface'] iptables = iface_extended['iptables_variant'] rule_definition = f'{iptables_nflog_chain} -i {iface} -m comment --comment FLOW_ACCOUNTING_RULE -j NFLOG --nflog-group 2 --nflog-size {default_captured_packet_size} --nflog-threshold 100' iptable_commands.append(f'sudo {iptables} -t {iptables_nflog_table} -I {rule_definition}') # change iptables for command in iptable_commands: cmd(command, raising=ConfigError) def get_config(): vc = Config() vc.set_level('') # Convert the VyOS config to an abstract internal representation flow_config = { 'flow-accounting-configured': vc.exists('system flow-accounting'), 'buffer-size': vc.return_value('system flow-accounting buffer-size'), 'disable-imt': _node_exists('system flow-accounting disable-imt'), 'syslog-facility': vc.return_value('system flow-accounting syslog-facility'), 'interfaces': None, 'sflow': { 'configured': vc.exists('system flow-accounting sflow'), 'agent-address': vc.return_value('system flow-accounting sflow agent-address'), 'sampling-rate': vc.return_value('system flow-accounting sflow sampling-rate'), 'servers': None }, 'netflow': { 'configured': vc.exists('system flow-accounting netflow'), 'engine-id': vc.return_value('system flow-accounting netflow engine-id'), 'max-flows': vc.return_value('system flow-accounting netflow max-flows'), 'sampling-rate': vc.return_value('system flow-accounting netflow sampling-rate'), 'source-ip': vc.return_value('system flow-accounting netflow source-ip'), 'version': vc.return_value('system flow-accounting netflow version'), 'timeout': { 'expint': vc.return_value('system flow-accounting netflow timeout expiry-interval'), 'general': vc.return_value('system flow-accounting netflow timeout flow-generic'), 'icmp': vc.return_value('system flow-accounting netflow timeout icmp'), 'maxlife': vc.return_value('system flow-accounting netflow timeout max-active-life'), 'tcp.fin': vc.return_value('system flow-accounting netflow timeout tcp-fin'), 'tcp': vc.return_value('system flow-accounting netflow timeout tcp-generic'), 'tcp.rst': vc.return_value('system flow-accounting netflow timeout tcp-rst'), 'udp': vc.return_value('system flow-accounting netflow timeout udp') }, 'servers': None } } # get interfaces list if vc.exists('system flow-accounting interface'): flow_config['interfaces'] = vc.return_values('system flow-accounting interface') # get sFlow collectors list if vc.exists('system flow-accounting sflow server'): flow_config['sflow']['servers'] = [] sflow_collectors = vc.list_nodes('system flow-accounting sflow server') for collector in sflow_collectors: port = default_sflow_server_port if vc.return_value("system flow-accounting sflow server {} port".format(collector)): port = vc.return_value("system flow-accounting sflow server {} port".format(collector)) flow_config['sflow']['servers'].append({ 'address': collector, 'port': port }) # get NetFlow collectors list if vc.exists('system flow-accounting netflow server'): flow_config['netflow']['servers'] = [] netflow_collectors = vc.list_nodes('system flow-accounting netflow server') for collector in netflow_collectors: port = default_netflow_server_port if vc.return_value("system flow-accounting netflow server {} port".format(collector)): port = vc.return_value("system flow-accounting netflow server {} port".format(collector)) flow_config['netflow']['servers'].append({ 'address': collector, 'port': port }) # get sflow agent-id if flow_config['sflow']['agent-address'] == None or flow_config['sflow']['agent-address'] == 'auto': flow_config['sflow']['agent-address'] = _sflow_default_agentip(vc) # get NetFlow version if not flow_config['netflow']['version']: flow_config['netflow']['version'] = default_netflow_version # convert NetFlow engine-id format, if this is necessary if flow_config['netflow']['engine-id'] and flow_config['netflow']['version'] == '5': regex_filter = re.compile('^\d+$') if regex_filter.search(flow_config['netflow']['engine-id']): flow_config['netflow']['engine-id'] = "{}:0".format(flow_config['netflow']['engine-id']) # return dict with flow-accounting configuration return flow_config def verify(config): # Verify that configuration is valid # skip all checks if flow-accounting was removed if not config['flow-accounting-configured']: return True # check if at least one collector is enabled if not (config['sflow']['configured'] or config['netflow']['configured'] or not config['disable-imt']): raise ConfigError("You need to configure at least one sFlow or NetFlow protocol, or not set \"disable-imt\" for flow-accounting") # Check if at least one interface is configured if not config['interfaces']: raise ConfigError("You need to configure at least one interface for flow-accounting") # check that all configured interfaces exists in the system for iface in config['interfaces']: if not iface in Section.interfaces(): # chnged from error to warning to allow adding dynamic interfaces and interface templates # raise ConfigError("The {} interface is not presented in the system".format(iface)) print("Warning: the {} interface is not presented in the system".format(iface)) # check sFlow configuration if config['sflow']['configured']: # check if at least one sFlow collector is configured if sFlow configuration is presented if not config['sflow']['servers']: raise ConfigError("You need to configure at least one sFlow server") # check that all sFlow collectors use the same IP protocol version sflow_collector_ipver = None for sflow_collector in config['sflow']['servers']: if sflow_collector_ipver: if sflow_collector_ipver != ip_address(sflow_collector['address']).version: raise ConfigError("All sFlow servers must use the same IP protocol") else: sflow_collector_ipver = ip_address(sflow_collector['address']).version # check agent-id for sFlow: we should avoid mixing IPv4 agent-id with IPv6 collectors and vice-versa for sflow_collector in config['sflow']['servers']: if ip_address(sflow_collector['address']).version != ip_address(config['sflow']['agent-address']).version: raise ConfigError("Different IP address versions cannot be mixed in \"sflow agent-address\" and \"sflow server\". You need to set manually the same IP version for \"agent-address\" as for all sFlow servers") # check if configured sFlow agent-id exist in the system agent_id_presented = None for iface in Section.interfaces(): for address in Interface(iface).get_addr(): # check an IP, if this is not loopback regex_filter = re.compile('^(?!(127)|(::1)|(fe80))(?P<ipaddr>[a-f\d\.:]+)/\d+$') if regex_filter.search(address): if regex_filter.search(address).group('ipaddr') == config['sflow']['agent-address']: agent_id_presented = True break if not agent_id_presented: raise ConfigError("Your \"sflow agent-address\" does not exist in the system") # check NetFlow configuration if config['netflow']['configured']: # check if at least one NetFlow collector is configured if NetFlow configuration is presented if not config['netflow']['servers']: raise ConfigError("You need to configure at least one NetFlow server") # check if configured netflow source-ip exist in the system if config['netflow']['source-ip']: source_ip_presented = None for iface in Interface.listing(): for address in Interface(iface).get_addr(): # check an IP regex_filter = re.compile('^(?!(127)|(::1)|(fe80))(?P<ipaddr>[a-f\d\.:]+)/\d+$') if regex_filter.search(address): if regex_filter.search(address).group('ipaddr') == config['netflow']['source-ip']: source_ip_presented = True break if not source_ip_presented: raise ConfigError("Your \"netflow source-ip\" does not exist in the system") # check if engine-id compatible with selected protocol version if config['netflow']['engine-id']: v5_filter = '^(\d|[1-9]\d|1\d{2}|2[0-4]\d|25[0-5]):(\d|[1-9]\d|1\d{2}|2[0-4]\d|25[0-5])$' v9v10_filter = '^(\d|[1-9]\d{1,8}|[1-3]\d{9}|4[01]\d{8}|42[0-8]\d{7}|429[0-3]\d{6}|4294[0-8]\d{5}|42949[0-5]\d{4}|429496[0-6]\d{3}|4294967[01]\d{2}|42949672[0-8]\d|429496729[0-5])$' if config['netflow']['version'] == '5': regex_filter = re.compile(v5_filter) if not regex_filter.search(config['netflow']['engine-id']): raise ConfigError("You cannot use NetFlow engine-id {} together with NetFlow protocol version {}".format(config['netflow']['engine-id'], config['netflow']['version'])) else: regex_filter = re.compile(v9v10_filter) if not regex_filter.search(config['netflow']['engine-id']): raise ConfigError("You cannot use NetFlow engine-id {} together with NetFlow protocol version {}".format(config['netflow']['engine-id'], config['netflow']['version'])) # return True if all checks were passed return True def generate(config): # skip all checks if flow-accounting was removed if not config['flow-accounting-configured']: return True # Calculate all necessary values if config['buffer-size']: # circular queue size config['plugin_pipe_size'] = int(config['buffer-size']) * 1024**2 else: config['plugin_pipe_size'] = default_plugin_pipe_size * 1024**2 # transfer buffer size # recommended value from pmacct developers 1/1000 of pipe size config['plugin_buffer_size'] = int(config['plugin_pipe_size'] / 1000) # Prepare a timeouts string timeout_string = '' for timeout_type, timeout_value in config['netflow']['timeout'].items(): if timeout_value: if timeout_string == '': timeout_string = "{}{}={}".format(timeout_string, timeout_type, timeout_value) else: timeout_string = "{}:{}={}".format(timeout_string, timeout_type, timeout_value) config['netflow']['timeout_string'] = timeout_string render(uacctd_conf_path, 'netflow/uacctd.conf.tmpl', { 'templatecfg': config, 'snaplen': default_captured_packet_size, }) def apply(config): # define variables command = None # Check if flow-accounting was removed and define command if not config['flow-accounting-configured']: command = 'systemctl stop uacctd.service' else: command = 'systemctl restart uacctd.service' # run command to start or stop flow-accounting cmd(command, raising=ConfigError, message='Failed to start/stop flow-accounting') # configure iptables rules for defined interfaces if config['interfaces']: _iptables_config(config['interfaces']) else: _iptables_config([]) if __name__ == '__main__': try: config = get_config() verify(config) generate(config) apply(config) except ConfigError as e: print(e) exit(1)