diff options
| -rw-r--r-- | interface-definitions/protocols-bfd.xml | 140 | ||||
| -rw-r--r-- | op-mode-definitions/show-protocols-bfd.xml | 46 | ||||
| -rwxr-xr-x | src/conf_mode/protocols_bfd.py | 231 |
3 files changed, 417 insertions, 0 deletions
diff --git a/interface-definitions/protocols-bfd.xml b/interface-definitions/protocols-bfd.xml new file mode 100644 index 000000000..62e2c87b9 --- /dev/null +++ b/interface-definitions/protocols-bfd.xml @@ -0,0 +1,140 @@ +<?xml version="1.0"?> +<!-- Bidirectional Forwarding Detection (BFD) configuration --> +<interfaceDefinition> + <node name="protocols"> + <children> + <node name="bfd" owner="${vyos_conf_scripts_dir}/protocols_bfd.py"> + <properties> + <help>Bidirectional Forwarding Detection (BFD)</help> + <priority>820</priority> + </properties> + <children> + <tagNode name="peer"> + <properties> + <help>Configures a new BFD peer to listen and talk to</help> + <valueHelp> + <format>ipv4</format> + <description>BFD peer IPv4 address</description> + </valueHelp> + <valueHelp> + <format>ipv6</format> + <description>BFD peer IPv6 address</description> + </valueHelp> + <constraint> + <validator name="ipv4-address"/> + <validator name="ipv6-address"/> + </constraint> + </properties> + <children> + <node name="source"> + <properties> + <help>Bind listener to specifid interface/address, mandatory for IPv6</help> + </properties> + <children> + <leafNode name="interface"> + <properties> + <help>Local interface to bind our peer listener to</help> + <completionHelp> + <script>${vyos_completion_dir}/list_interfaces.py</script> + </completionHelp> + </properties> + </leafNode> + <leafNode name="address"> + <properties> + <help>Local address to bind our peer listener to</help> + <valueHelp> + <format>ipv4</format> + <description>Local IPv4 address used to connect to the peer</description> + </valueHelp> + <valueHelp> + <format>ipv6</format> + <description>Local IPv6 address used to connect to the peer</description> + </valueHelp> + <constraint> + <validator name="ipv4-address"/> + <validator name="ipv6-address"/> + </constraint> + </properties> + </leafNode> + </children> + </node> + <node name="interval"> + <properties> + <help>Configure timer intervals</help> + </properties> + <children> + <leafNode name="receive"> + <properties> + <help>Minimum interval of receiving control packets</help> + <valueHelp> + <format>10-60000</format> + <description>Interval in milliseconds</description> + </valueHelp> + <constraint> + <validator name="numeric" argument="--range 10-60000"/> + </constraint> + </properties> + </leafNode> + <leafNode name="transmit"> + <properties> + <help>Minimum interval of transmitting control packets</help> + <valueHelp> + <format>10-60000</format> + <description>Interval in milliseconds</description> + </valueHelp> + <constraint> + <validator name="numeric" argument="--range 10-60000"/> + </constraint> + </properties> + </leafNode> + <leafNode name="multiplier"> + <properties> + <help>Multiplier to determine packet loss</help> + <valueHelp> + <format>2-255</format> + <description>Remote transmission interval will be multiplied by this value</description> + </valueHelp> + <constraint> + <validator name="numeric" argument="--range 2-255"/> + </constraint> + </properties> + </leafNode> + <leafNode name="echo-interval"> + <properties> + <help>Echo receive transmission interval</help> + <valueHelp> + <format>10-60000</format> + <description>The minimal echo receive transmission interval that this system is capable of handling</description> + </valueHelp> + <constraint> + <validator name="numeric" argument="--range 10-60000"/> + </constraint> + </properties> + </leafNode> + </children> + </node> + <leafNode name="shutdown"> + <properties> + <help>Disable this peer</help> + <valueless/> + </properties> + </leafNode> + <leafNode name="multihop"> + <properties> + <help>Allow this BFD peer to not be directly connected</help> + <valueless/> + </properties> + </leafNode> + <leafNode name="echo-mode"> + <properties> + <help>Enables the echo transmission mode</help> + <valueless/> + </properties> + </leafNode> + </children> + </tagNode> + </children> + </node> + </children> + </node> +</interfaceDefinition> diff --git a/op-mode-definitions/show-protocols-bfd.xml b/op-mode-definitions/show-protocols-bfd.xml new file mode 100644 index 000000000..398a81d1b --- /dev/null +++ b/op-mode-definitions/show-protocols-bfd.xml @@ -0,0 +1,46 @@ +<?xml version="1.0"?> +<interfaceDefinition> + <node name="show"> + <children> + <node name="protocols"> + <children> + <node name="bfd"> + <children> + <node name="peer"> + <properties> + <help>Show all Bidirectional Forwarding Detection (BFD) peer status</help> + </properties> + <command>/usr/bin/vtysh -c "show bfd peers"</command> + <children> + <leafNode name="counters"> + <properties> + <help>Show Bidirectional Forwarding Detection (BFD) peer counters</help> + </properties> + <command>/usr/bin/vtysh -c "show bfd peers counters"</command> + </leafNode> + </children> + </node> + <tagNode name="peer"> + <properties> + <help>Show Bidirectional Forwarding Detection (BFD) peer status</help> + <completionHelp> + <script>/usr/bin/vtysh -c "show bfd peers" | awk '/[:blank:]*peer/ { printf "%s\n", $2 }'</script> + </completionHelp> + </properties> + <command>/usr/bin/vtysh -c "show bfd peers" | awk -v BFD_PEER=$5 '($0 ~ peer BFD_PEER) { system("/usr/bin/vtysh -c \"show bfd " $0 "\"") }'</command> + <children> + <leafNode name="counters"> + <properties> + <help>Show Bidirectional Forwarding Detection (BFD) peer counters</help> + </properties> + <command>/usr/bin/vtysh -c "show bfd peers" | awk -v BFD_PEER=$5 '($0 ~ peer BFD_PEER) { system("/usr/bin/vtysh -c \"show bfd " $0 " counters\"") }'</command> + </leafNode> + </children> + </tagNode> + </children> + </node> + </children> + </node> + </children> + </node> +</interfaceDefinition> diff --git a/src/conf_mode/protocols_bfd.py b/src/conf_mode/protocols_bfd.py new file mode 100755 index 000000000..9ca194edd --- /dev/null +++ b/src/conf_mode/protocols_bfd.py @@ -0,0 +1,231 @@ +#!/usr/bin/env python3 +# +# Copyright (C) 2019 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 sys +import jinja2 +import copy +import os +import vyos.validate + +from vyos import ConfigError +from vyos.config import Config + +config_file = r'/tmp/bfd.frr' + +# Please be careful if you edit the template. +config_tmpl = """ +! +bfd +{% for peer in old_peers -%} + no peer {{ peer.remote }}{% if peer.multihop %} multihop{% endif %}{% if peer.src_addr %} local-address {{ peer.src_addr }}{% endif %}{% if peer.src_if %} interface {{ peer.src_if }}{% endif %} +{% endfor -%} +! +{% for peer in new_peers -%} + peer {{ peer.remote }}{% if peer.multihop %} multihop{% endif %}{% if peer.src_addr %} local-address {{ peer.src_addr }}{% endif %}{% if peer.src_if %} interface {{ peer.src_if }}{% endif %} + detect-multiplier {{ peer.multiplier }} + receive-interval {{ peer.rx_interval }} + transmit-interval {{ peer.tx_interval }} + {% if peer.echo_mode %}echo-mode{% endif %} + {% if peer.echo_interval != '' %}echo-interval {{ peer.echo_interval }}{% endif %} + {% if not peer.shutdown %}no {% endif %}shutdown +{% endfor -%} +! +""" + +default_config_data = { + 'new_peers': [], + 'old_peers' : [] +} + +# get configuration for BFD peer from proposed or effective configuration +def get_bfd_peer_config(peer, conf_mode="proposed"): + conf = Config() + conf.set_level('protocols bfd peer {0}'.format(peer)) + + bfd_peer = { + 'remote': peer, + 'shutdown': False, + 'src_if': '', + 'src_addr': '', + 'multiplier': '3', + 'rx_interval': '300', + 'tx_interval': '300', + 'multihop': False, + 'echo_interval': '', + 'echo_mode': False, + } + + # Check if individual peer is disabled + if conf_mode == "effective" and conf.exists_effective('shutdown'): + bfd_peer['shutdown'] = True + if conf_mode == "proposed" and conf.exists('shutdown'): + bfd_peer['shutdown'] = True + + # Check if peer has a local source interface configured + if conf_mode == "effective" and conf.exists_effective('source interface'): + bfd_peer['src_if'] = conf.return_effective_value('source interface') + if conf_mode == "proposed" and conf.exists('source interface'): + bfd_peer['src_if'] = conf.return_value('source interface') + + # Check if peer has a local source address configured - this is mandatory for IPv6 + if conf_mode == "effective" and conf.exists_effective('source address'): + bfd_peer['src_addr'] = conf.return_effective_value('source address') + if conf_mode == "proposed" and conf.exists('source address'): + bfd_peer['src_addr'] = conf.return_value('source address') + + # Tell BFD daemon that we should expect packets with TTL less than 254 + # (because it will take more than one hop) and to listen on the multihop + # port (4784) + if conf_mode == "effective" and conf.exists_effective('multihop'): + bfd_peer['multihop'] = True + if conf_mode == "proposed" and conf.exists('multihop'): + bfd_peer['multihop'] = True + + # Configures the minimum interval that this system is capable of receiving + # control packets. The default value is 300 milliseconds. + if conf_mode == "effective" and conf.exists_effective('interval receive'): + bfd_peer['rx_interval'] = conf.return_effective_value('interval receive') + if conf_mode == "proposed" and conf.exists('interval receive'): + bfd_peer['rx_interval'] = conf.return_value('interval receive') + + # The minimum transmission interval (less jitter) that this system wants + # to use to send BFD control packets. + if conf_mode == "effective" and conf.exists_effective('interval transmit'): + bfd_peer['tx_interval'] = conf.return_effective_value('interval transmit') + if conf_mode == "proposed" and conf.exists('interval transmit'): + bfd_peer['tx_interval'] = conf.return_value('interval transmit') + + # Configures the detection multiplier to determine packet loss. The remote + # transmission interval will be multiplied by this value to determine the + # connection loss detection timer. The default value is 3. + if conf_mode == "effective" and conf.exists_effective('interval multiplier'): + bfd_peer['multiplier'] = conf.return_effective_value('interval multiplier') + if conf_mode == "proposed" and conf.exists('interval multiplier'): + bfd_peer['multiplier'] = conf.return_value('interval multiplier') + + # Configures the minimal echo receive transmission interval that this system is capable of handling + if conf_mode == "effective" and conf.exists_effective('interval echo-interval'): + bfd_peer['echo_interval'] = conf.return_effective_value('interval echo-interval') + if conf_mode == "proposed" and conf.exists('interval echo-interval'): + bfd_peer['echo_interval'] = conf.return_value('interval echo-interval') + + # Enables or disables the echo transmission mode + if conf_mode == "effective" and conf.exists_effective('echo-mode'): + bfd_peer['echo_mode'] = True + if conf_mode == "proposed" and conf.exists('echo-mode'): + bfd_peer['echo_mode'] = True + + return bfd_peer + +def get_config(): + bfd = copy.deepcopy(default_config_data) + conf = Config() + if not (conf.exists('protocols bfd') or conf.exists_effective('protocols bfd')): + return None + else: + conf.set_level('protocols bfd') + + # as we have to use vtysh to talk to FRR we also need to know + # which peers are gone due to a config removal - thus we read in + # all peers (active or to delete) + for peer in conf.list_effective_nodes('peer'): + bfd['old_peers'].append(get_bfd_peer_config(peer, "effective")) + + for peer in conf.list_nodes('peer'): + bfd['new_peers'].append(get_bfd_peer_config(peer)) + + # find deleted peers + set_new_peers = set(conf.list_nodes('peer')) + set_old_peers = set(conf.list_effective_nodes('peer')) + bfd['deleted_peers'] = set_old_peers - set_new_peers + + return bfd + +def verify(bfd): + if bfd is None: + return None + + # some variables to use later + conf = Config() + + for peer in bfd['new_peers']: + # IPv6 peers require an explicit local address/interface combination + if vyos.validate.is_ipv6(peer['remote']): + if not (peer['src_if'] and peer['src_addr']): + raise ConfigError('BFD IPv6 peers require explicit local address and interface setting') + + # multihop require source address + if peer['multihop'] and not peer['src_addr']: + raise ConfigError('Multihop require source address') + + # multihop and echo-mode cannot be used together + if peer['multihop'] and peer['echo_mode']: + raise ConfigError('Multihop and echo-mode cannot be used together') + + # multihop doesn't accept interface names + if peer['multihop'] and peer['src_if']: + raise ConfigError('Multihop and source interface cannot be used together') + + # echo interval can be configured only with enabled echo-mode + if peer['echo_interval'] != '' and not peer['echo_mode']: + raise ConfigError('echo-interval can be configured only with enabled echo-mode') + + # check if we deleted peers are not used in configuration + if conf.exists('protocols bgp'): + bgp_as = conf.list_nodes('protocols bgp')[0] + + # check BGP neighbors + for peer in bfd['deleted_peers']: + if conf.exists('protocols bgp {0} neighbor {1} bfd'.format(bgp_as, peer)): + raise ConfigError('Cannot delete BFD peer {0}: it is used in BGP configuration'.format(peer)) + if conf.exists('protocols bgp {0} neighbor {1} peer-group'.format(bgp_as, peer)): + peer_group = conf.return_value('protocols bgp {0} neighbor {1} peer-group'.format(bgp_as, peer)) + if conf.exists('protocols bgp {0} peer-group {1} bfd'.format(bgp_as, peer_group)): + raise ConfigError('Cannot delete BFD peer {0}: it belongs to BGP peer-group {1} with enabled BFD'.format(peer, peer_group)) + + return None + +def generate(bfd): + if bfd is None: + return None + + return None + +def apply(bfd): + if bfd is None: + return None + + tmpl = jinja2.Template(config_tmpl) + config_text = tmpl.render(bfd) + with open(config_file, 'w') as f: + f.write(config_text) + + os.system("sudo vtysh -d bfdd -f " + config_file) + if os.path.exists(config_file): + os.remove(config_file) + + return None + +if __name__ == '__main__': + try: + c = get_config() + verify(c) + generate(c) + apply(c) + except ConfigError as e: + print(e) + sys.exit(1) |