summaryrefslogtreecommitdiff
path: root/src/conf_mode/system_flow-accounting.py
diff options
context:
space:
mode:
Diffstat (limited to 'src/conf_mode/system_flow-accounting.py')
-rwxr-xr-xsrc/conf_mode/system_flow-accounting.py320
1 files changed, 320 insertions, 0 deletions
diff --git a/src/conf_mode/system_flow-accounting.py b/src/conf_mode/system_flow-accounting.py
new file mode 100755
index 000000000..206f513c8
--- /dev/null
+++ b/src/conf_mode/system_flow-accounting.py
@@ -0,0 +1,320 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2018-2023 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
+from ipaddress import ip_address
+
+from vyos.base import Warning
+from vyos.config import Config
+from vyos.config import config_dict_merge
+from vyos.configverify import verify_vrf
+from vyos.ifconfig import Section
+from vyos.template import render
+from vyos.utils.process import call
+from vyos.utils.process import cmd
+from vyos.utils.process import run
+from vyos.utils.network import is_addr_assigned
+from vyos import ConfigError
+from vyos import airbag
+airbag.enable()
+
+uacctd_conf_path = '/run/pmacct/uacctd.conf'
+systemd_service = 'uacctd.service'
+systemd_override = f'/run/systemd/system/{systemd_service}.d/override.conf'
+nftables_nflog_table = 'raw'
+nftables_nflog_chain = 'VYOS_PREROUTING_HOOK'
+egress_nftables_nflog_table = 'inet mangle'
+egress_nftables_nflog_chain = 'FORWARD'
+
+# get nftables rule dict for chain in table
+def _nftables_get_nflog(chain, table):
+ # define list with rules
+ rules = []
+
+ # prepare regex for parsing rules
+ rule_pattern = '[io]ifname "(?P<interface>[\w\.\*\-]+)".*handle (?P<handle>[\d]+)'
+ rule_re = re.compile(rule_pattern)
+
+ # run nftables, save output and split it by lines
+ nftables_command = f'nft -a list chain {table} {chain}'
+ tmp = cmd(nftables_command, message='Failed to get flows list')
+ # parse each line and add information to list
+ for current_rule in tmp.splitlines():
+ if 'FLOW_ACCOUNTING_RULE' not in current_rule:
+ continue
+ current_rule_parsed = rule_re.search(current_rule)
+ if current_rule_parsed:
+ groups = current_rule_parsed.groupdict()
+ rules.append({ 'interface': groups["interface"], 'table': table, 'handle': groups["handle"] })
+
+ # return list with rules
+ return rules
+
+def _nftables_config(configured_ifaces, direction, length=None):
+ # define list of nftables commands to modify settings
+ nftable_commands = []
+ nftables_chain = nftables_nflog_chain
+ nftables_table = nftables_nflog_table
+
+ if direction == "egress":
+ nftables_chain = egress_nftables_nflog_chain
+ nftables_table = egress_nftables_nflog_table
+
+ # prepare extended list with configured interfaces
+ configured_ifaces_extended = []
+ for iface in configured_ifaces:
+ configured_ifaces_extended.append({ 'iface': iface })
+
+ # get currently configured interfaces with nftables rules
+ active_nflog_rules = _nftables_get_nflog(nftables_chain, nftables_table)
+
+ # compare current active list with configured one and delete excessive interfaces, add missed
+ active_nflog_ifaces = []
+ for rule in active_nflog_rules:
+ interface = rule['interface']
+ if interface not in configured_ifaces:
+ table = rule['table']
+ handle = rule['handle']
+ nftable_commands.append(f'nft delete rule {table} {nftables_chain} handle {handle}')
+ else:
+ active_nflog_ifaces.append({
+ 'iface': interface,
+ })
+
+ # do not create new rules for already configured interfaces
+ for iface in active_nflog_ifaces:
+ if iface in active_nflog_ifaces and iface in configured_ifaces_extended:
+ configured_ifaces_extended.remove(iface)
+
+ # create missed rules
+ for iface_extended in configured_ifaces_extended:
+ iface = iface_extended['iface']
+ iface_prefix = "o" if direction == "egress" else "i"
+ rule_definition = f'{iface_prefix}ifname "{iface}" counter log group 2 snaplen {length} queue-threshold 100 comment "FLOW_ACCOUNTING_RULE"'
+ nftable_commands.append(f'nft insert rule {nftables_table} {nftables_chain} {rule_definition}')
+ # Also add IPv6 ingres logging
+ if nftables_table == nftables_nflog_table:
+ nftable_commands.append(f'nft insert rule ip6 {nftables_table} {nftables_chain} {rule_definition}')
+
+ # change nftables
+ for command in nftable_commands:
+ cmd(command, raising=ConfigError)
+
+
+def _nftables_trigger_setup(operation: str) -> None:
+ """Add a dummy rule to unlock the main pmacct loop with a packet-trigger
+
+ Args:
+ operation (str): 'add' or 'delete' a trigger
+ """
+ # check if a chain exists
+ table_exists = False
+ if run('nft -snj list table ip pmacct') == 0:
+ table_exists = True
+
+ if operation == 'delete' and table_exists:
+ nft_cmd: str = 'nft delete table ip pmacct'
+ cmd(nft_cmd, raising=ConfigError)
+ if operation == 'add' and not table_exists:
+ nft_cmds: list[str] = [
+ 'nft add table ip pmacct',
+ 'nft add chain ip pmacct pmacct_out { type filter hook output priority raw - 50 \\; policy accept \\; }',
+ 'nft add rule ip pmacct pmacct_out oif lo ip daddr 127.0.254.0 counter log group 2 snaplen 1 queue-threshold 0 comment NFLOG_TRIGGER'
+ ]
+ for nft_cmd in nft_cmds:
+ cmd(nft_cmd, raising=ConfigError)
+
+
+def get_config(config=None):
+ if config:
+ conf = config
+ else:
+ conf = Config()
+ base = ['system', 'flow-accounting']
+ if not conf.exists(base):
+ return None
+
+ flow_accounting = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)
+
+ # We have gathered the dict representation of the CLI, but there are
+ # default values which we need to conditionally update into the
+ # dictionary retrieved.
+ default_values = conf.get_config_defaults(**flow_accounting.kwargs,
+ recursive=True)
+
+ # delete individual flow type defaults - should only be added if user
+ # sets this feature
+ for flow_type in ['sflow', 'netflow']:
+ if flow_type not in flow_accounting and flow_type in default_values:
+ del default_values[flow_type]
+
+ flow_accounting = config_dict_merge(default_values, flow_accounting)
+
+ return flow_accounting
+
+def verify(flow_config):
+ if not flow_config:
+ return None
+
+ # check if at least one collector is enabled
+ if 'sflow' not in flow_config and 'netflow' not in flow_config and 'disable_imt' in flow_config:
+ raise ConfigError('You need to configure at least sFlow or NetFlow, ' \
+ 'or not set "disable-imt" for flow-accounting!')
+
+ # Check if at least one interface is configured
+ if 'interface' not in flow_config:
+ raise ConfigError('Flow accounting requires at least one interface to ' \
+ 'be configured!')
+
+ # check that all configured interfaces exists in the system
+ for interface in flow_config['interface']:
+ if interface not in Section.interfaces():
+ # Changed from error to warning to allow adding dynamic interfaces
+ # and interface templates
+ Warning(f'Interface "{interface}" is not presented in the system')
+
+ # check sFlow configuration
+ if 'sflow' in flow_config:
+ # check if at least one sFlow collector is configured
+ if 'server' not in flow_config['sflow']:
+ 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 server in flow_config['sflow']['server']:
+ if sflow_collector_ipver:
+ if sflow_collector_ipver != ip_address(server).version:
+ raise ConfigError("All sFlow servers must use the same IP protocol")
+ else:
+ sflow_collector_ipver = ip_address(server).version
+
+ # check if vrf is defined for Sflow
+ verify_vrf(flow_config)
+ sflow_vrf = None
+ if 'vrf' in flow_config:
+ sflow_vrf = flow_config['vrf']
+
+ # check agent-id for sFlow: we should avoid mixing IPv4 agent-id with IPv6 collectors and vice-versa
+ for server in flow_config['sflow']['server']:
+ if 'agent_address' in flow_config['sflow']:
+ if ip_address(server).version != ip_address(flow_config['sflow']['agent_address']).version:
+ raise ConfigError('IPv4 and IPv6 addresses can not be mixed in "sflow agent-address" and "sflow '\
+ 'server". You need to set the same IP version for both "agent-address" and '\
+ 'all sFlow servers')
+
+ if 'agent_address' in flow_config['sflow']:
+ tmp = flow_config['sflow']['agent_address']
+ if not is_addr_assigned(tmp, sflow_vrf):
+ raise ConfigError(f'Configured "sflow agent-address {tmp}" does not exist in the system!')
+
+ # Check if configured sflow source-address exist in the system
+ if 'source_address' in flow_config['sflow']:
+ if not is_addr_assigned(flow_config['sflow']['source_address'], sflow_vrf):
+ tmp = flow_config['sflow']['source_address']
+ raise ConfigError(f'Configured "sflow source-address {tmp}" does not exist on the system!')
+
+ # check NetFlow configuration
+ if 'netflow' in flow_config:
+ # check if vrf is defined for netflow
+ netflow_vrf = None
+ if 'vrf' in flow_config:
+ netflow_vrf = flow_config['vrf']
+
+ # check if at least one NetFlow collector is configured if NetFlow configuration is presented
+ if 'server' not in flow_config['netflow']:
+ raise ConfigError('You need to configure at least one NetFlow server!')
+
+ # Check if configured netflow source-address exist in the system
+ if 'source_address' in flow_config['netflow']:
+ if not is_addr_assigned(flow_config['netflow']['source_address'], netflow_vrf):
+ tmp = flow_config['netflow']['source_address']
+ raise ConfigError(f'Configured "netflow source-address {tmp}" does not exist on the system!')
+
+ # Check if engine-id compatible with selected protocol version
+ if 'engine_id' in flow_config['netflow']:
+ 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])$'
+ v9v10_filter = '^(\d|[1-9]\d{1,8}|[1-3]\d{9}|4[01]\d{8}|42[0-8]\d{7}|429[0-3]\d{6}|4294[0-8]\d{5}|42949[0-5]\d{4}|429496[0-6]\d{3}|4294967[01]\d{2}|42949672[0-8]\d|429496729[0-5])$'
+ engine_id = flow_config['netflow']['engine_id']
+ version = flow_config['netflow']['version']
+
+ if flow_config['netflow']['version'] == '5':
+ regex_filter = re.compile(v5_filter)
+ if not regex_filter.search(engine_id):
+ raise ConfigError(f'You cannot use NetFlow engine-id "{engine_id}" '\
+ f'together with NetFlow protocol version "{version}"!')
+ else:
+ regex_filter = re.compile(v9v10_filter)
+ if not regex_filter.search(flow_config['netflow']['engine_id']):
+ raise ConfigError(f'Can not use NetFlow engine-id "{engine_id}" together '\
+ f'with NetFlow protocol version "{version}"!')
+
+ # return True if all checks were passed
+ return True
+
+def generate(flow_config):
+ if not flow_config:
+ return None
+
+ render(uacctd_conf_path, 'pmacct/uacctd.conf.j2', flow_config)
+ render(systemd_override, 'pmacct/override.conf.j2', flow_config)
+ # Reload systemd manager configuration
+ call('systemctl daemon-reload')
+
+def apply(flow_config):
+ # Check if flow-accounting was removed and define command
+ if not flow_config:
+ _nftables_config([], 'ingress')
+ _nftables_config([], 'egress')
+
+ # Stop flow-accounting daemon and remove configuration file
+ call(f'systemctl stop {systemd_service}')
+ if os.path.exists(uacctd_conf_path):
+ os.unlink(uacctd_conf_path)
+
+ # must be done after systemctl
+ _nftables_trigger_setup('delete')
+
+ return
+
+ # Start/reload flow-accounting daemon
+ call(f'systemctl restart {systemd_service}')
+
+ # configure nftables rules for defined interfaces
+ if 'interface' in flow_config:
+ _nftables_config(flow_config['interface'], 'ingress', flow_config['packet_length'])
+
+ # configure egress the same way if configured otherwise remove it
+ if 'enable_egress' in flow_config:
+ _nftables_config(flow_config['interface'], 'egress', flow_config['packet_length'])
+ else:
+ _nftables_config([], 'egress')
+
+ # add a trigger for signal processing
+ _nftables_trigger_setup('add')
+
+
+if __name__ == '__main__':
+ try:
+ config = get_config()
+ verify(config)
+ generate(config)
+ apply(config)
+ except ConfigError as e:
+ print(e)
+ exit(1)