tunnel: T2028: move interface tunnel to XML/Python

This patch migrates the "interface tunnel" section to xml/python

2 files changed, 514 insertions, 0 deletions

diff --git a/src/completion/list_local.py b/src/completion/list_local.py
new file mode 100755
index 000000000..ddb65c05c
--- /dev/null
+++ b/src/completion/list_local.py
@@ -0,0 +1,24 @@
+#!/usr/bin/env python3
+
+import json
+import argparse
+import subprocess
+
+# [{"ifindex":1,"ifname":"lo","flags":["LOOPBACK","UP","LOWER_UP"],"mtu":65536,"qdisc":"noqueue","operstate":"UNKNOWN","group":"default","txqlen":1000,"link_type":"loopback","address":"00:00:00:00:00:00","broadcast":"00:00:00:00:00:00","addr_info":[{"family":"inet","local":"127.0.0.1","prefixlen":8,"scope":"host","label":"lo","valid_life_time":4294967295,"preferred_life_time":4294967295},{"family":"inet6","local":"::1","prefixlen":128,"scope":"host","valid_life_time":4294967295,"preferred_life_time":4294967295}]},{"ifindex":2,"ifname":"eth0","flags":["BROADCAST","MULTICAST","UP","LOWER_UP"],"mtu":1500,"qdisc":"pfifo_fast","operstate":"UP","group":"default","txqlen":1000,"link_type":"ether","address":"08:00:27:fa:12:53","broadcast":"ff:ff:ff:ff:ff:ff","addr_info":[{"family":"inet","local":"10.0.2.15","prefixlen":24,"broadcast":"10.0.2.255","scope":"global","label":"eth0","valid_life_time":4294967295,"preferred_life_time":4294967295},{"family":"inet6","local":"fe80::a00:27ff:fefa:1253","prefixlen":64,"scope":"link","valid_life_time":4294967295,"preferred_life_time":4294967295}]},{"ifindex":3,"ifname":"eth1","flags":["BROADCAST","MULTICAST","UP","LOWER_UP"],"mtu":1500,"qdisc":"pfifo_fast","operstate":"UP","group":"default","txqlen":1000,"link_type":"ether","address":"08:00:27:0d:25:dc","broadcast":"ff:ff:ff:ff:ff:ff","addr_info":[{"family":"inet6","local":"fe80::a00:27ff:fe0d:25dc","prefixlen":64,"scope":"link","valid_life_time":4294967295,"preferred_life_time":4294967295}]},{"ifindex":4,"ifname":"eth2","flags":["BROADCAST","MULTICAST","UP","LOWER_UP"],"mtu":1500,"qdisc":"pfifo_fast","operstate":"UP","group":"default","txqlen":1000,"link_type":"ether","address":"08:00:27:68:d0:b1","broadcast":"ff:ff:ff:ff:ff:ff","addr_info":[{"family":"inet6","local":"fe80::a00:27ff:fe68:d0b1","prefixlen":64,"scope":"link","valid_life_time":4294967295,"preferred_life_time":4294967295}]},{"ifindex":5,"ifname":"eth3","flags":["BROADCAST","MULTICAST","UP","LOWER_UP"],"mtu":1500,"qdisc":"pfifo_fast","operstate":"UP","group":"default","txqlen":1000,"link_type":"ether","address":"08:00:27:f0:17:c5","broadcast":"ff:ff:ff:ff:ff:ff","addr_info":[{"family":"inet6","local":"fe80::a00:27ff:fef0:17c5","prefixlen":64,"scope":"link","valid_life_time":4294967295,"preferred_life_time":4294967295}]}]
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser()
+    group = parser.add_mutually_exclusive_group()
+
+    cmd = 'ip -j address show'
+    out = subprocess.check_output(cmd.split()).decode().strip()
+    data = json.loads(out)
+
+
+    interfaces = []
+    for interface in data:
+        if not 'addr_info' in interface:
+            continue
+        interfaces.extend(interface['addr_info'])
+
+    print(' '.join([interface['local'] for interface in interfaces if 'local' in interface]))
diff --git a/src/conf_mode/interfaces-tunnel.py b/src/conf_mode/interfaces-tunnel.py
new file mode 100755
index 000000000..67b58719b
--- /dev/null
+++ b/src/conf_mode/interfaces-tunnel.py
@@ -0,0 +1,490 @@
+#!/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 os
+import netifaces
+
+from sys import exit
+from copy import deepcopy
+
+from vyos.config import Config
+from vyos.ifconfig import Interface, GREIf, GRETapIf, IPIPIf, IP6GREIf, IPIP6If, IP6IP6If, SitIf, Sit6RDIf
+from vyos.ifconfig.afi import IP4, IP6
+from vyos.configdict import list_diff
+from vyos.validate import is_ipv4, is_ipv6
+from vyos import ConfigError
+
+
+class FixedDict(dict):
+    def __init__ (self, **options):
+        self._allowed = options.keys()
+        super().__init__(**options)
+
+    def __setitem__ (self, k, v):
+        if k not in self._allowed:
+            raise ConfigError(f'Option "{k}" has no defined default')
+        super().__setitem__(k, v)
+
+
+class ConfigurationState (Config):
+    def __init__ (self, section, default):
+        super().__init__()
+        self.section = section
+        self.default = deepcopy(default)
+        self.options = FixedDict(**default)
+        self.actions = {
+            'create': [],  # the key did not exist and was added
+            'static': [],  # the key exists and its value was not modfied
+            'modify': [],  # the key exists and its value was modified
+            'absent': [],  # the key is not present
+            'delete': [],  # the key was present and was deleted
+        }
+        self.changes = {}
+        if not self.exists(section):
+            self.changes['section'] = 'delete'
+        elif self.exists_effective(section):
+            self.changes['section'] = 'modify'
+        else:
+            self.changes['section'] = 'create'
+
+    def _act(self, section):
+        if self.exists(section):
+            if self.exists_effective(section):
+                if self.return_value(section) != self.return_effective_value(section):
+                    return 'modify'
+                return 'static'
+            return 'create'
+        else:
+            if self.exists_effective(section):
+                return 'delete'
+            return 'absent'
+
+    def _action (self, name, key):
+        action = self._act(key)
+        self.changes[name] = action
+        self.actions[action].append(name)
+        return action
+
+    def _get(self, name, key, default, getter):
+        value = getter(key)
+        if not value:
+            if default:
+                self.options[name] = default
+                return
+            self.options[name] = self.default[name]
+            return
+        self.options[name] = value
+
+    def get_value(self, name, key, default=None):
+        if self._action(name, key) in ('delete', 'absent'):
+            return
+        return self._get(name, key, default, self.return_value)
+
+    def get_values(self, name, key, default=None):
+        if self._action(name, key) in ('delete', 'absent'):
+            return
+        return self._get(name, key, default, self.return_values)
+
+    def get_effective(self, name, key, default=None):
+        self._action(name, key)
+        return self._get(name, key, default, self.return_effective_value)
+
+    def get_effectives(self, name, key, default=None):
+        self._action(name, key)
+        return self._get(name, key, default, self.return_effectives_value)
+
+    def load(self, mapping):
+        for local_name, (config_name, multiple, default) in mapping.items():
+            if multiple:
+                self.get_values(local_name, config_name, default)
+            else:
+                self.get_value(local_name, config_name, default)
+
+    def remove_default (self,*options):
+        for option in options:
+            if self.exists(option) and self_return_value(option) != self.default[option]:
+                continue
+            del self.options[option]
+
+    def to_dict (self):
+        # as we have to use a dict() for the API for verify and apply the options
+        return {
+            'options': self.options,
+            'changes': self.changes,
+            'actions': self.actions,
+        }
+
+default_config_data = {
+    # interface definition
+    'addresses-add': [],
+    'addresses-del': [],
+    'state': 'up',
+    'dhcp-interface': '',
+    'link_detect': 1,
+    'ip': False,
+    'ipv6': False,
+    'nhrp': [],
+    # internal
+    'tunnel': {},
+    # the following names are exactly matching the name
+    # for the ip command and must not be changed
+    'ifname': '',
+    'type': '',
+    'alias': '',
+    'mtu': '1476',
+    'local': '',
+    'remote': '',
+    'multicast': 'disable',
+    'allmulticast': 'disable',
+    'ttl': '255',
+    'tos': 'inherit',
+    'key': '',
+    'encaplimit': '4',
+    'flowlabel': 'inherit',
+    'hoplimit': '64',
+    'tclass': 'inherit',
+    '6rd-prefix': '',
+    '6rd-relay-prefix': '',
+}
+
+# dict name -> config name, multiple values, default
+mapping = {
+    'type':                ('encapsulation', False, None),
+    'alias':               ('description', False, None),
+    'mtu':                 ('mtu', False, None),
+    'local':               ('local-ip', False, None),
+    'remote':              ('remote-ip', False, None),
+    'multicast':           ('multicast', False, None),
+    'ttl':                 ('parameters ip ttl', False, None),
+    'tos':                 ('parameters ip tos', False, None),
+    'key':                 ('parameters ip key', False, None),
+    'encaplimit':          ('parameters ipv6 encaplimit', False, None),
+    'flowlabel':           ('parameters ipv6 flowlabel', False, None),
+    'hoplimit':            ('parameters ipv6 hoplimit', False, None),
+    'tclass':              ('parameters ipv6 tclass', False, None),
+    '6rd-prefix':          ('6rd-prefix', False, None),
+    '6rd-relay-prefix':    ('6rd-relay-prefix', False, None),
+    'dhcp-interface':      ('dhcp-interface', False, None),
+    'state':               ('disable', False, 'down'),
+    'link_detect':         ('disable-link-detect', False, 2),
+    'addresses-add':       ('address', True, None),
+}
+
+def get_class (options):
+    dispatch = {
+        'gre': GREIf,
+        'gre-bridge': GRETapIf,
+        'ipip': IPIPIf,
+        'ipip6': IPIP6If,
+        'ip6ip6': IP6IP6If,
+        'ip6gre': IP6GREIf,
+        'sit': SitIf,
+    }
+
+    kls = dispatch[options['type']]
+    if options['type'] == 'gre' and not options['remote']:
+        # will use GreTapIf on GreIf deletion but it does not matter
+        return GRETapIf
+    elif options['type'] == 'sit' and options['6rd-prefix']:
+        # will use SitIf on Sit6RDIf deletion but it does not matter
+        return Sit6RDIf
+    return kls
+
+def get_interface_ip (ifname):
+    if not ifname:
+        return ''
+    try:
+        addrs = Interface(ifname).get_addr()
+        if addrs:
+            return addrs[0].split('/')[0]
+    except Exception:
+        return ''
+
+def get_afi (ip):
+    return IP6 if is_ipv6(ip) else IP4
+
+def ip_proto (afi):
+    return 6 if afi == IP6 else 4
+
+
+def get_config():
+    ifname = os.environ.get('VYOS_TAGNODE_VALUE','')
+    if not ifname:
+        raise ConfigError('Interface not specified')
+
+    conf = ConfigurationState('interfaces tunnel ' + ifname, default_config_data)
+    options = conf.options
+    changes = conf.changes
+    options['ifname'] = ifname
+
+    # set new configuration level
+    conf.set_level(conf.section)
+
+    if changes['section'] == 'delete':
+        conf.get_effective('type', mapping['type'][0])
+        conf.set_level('protocols nhrp tunnel')
+        options['nhrp'] = conf.list_nodes('')
+        return conf.to_dict()
+
+    # load all the configuration option according to the mapping
+    conf.load(mapping)
+
+    # remove default value if not set and not required
+    afi_local = get_afi(options['local'])
+    if afi_local == IP6:
+        conf.remove_default('ttl', 'tos', 'key')
+    if afi_local == IP4:
+        conf.remove_default('encaplimit', 'flowlabel', 'hoplimit', 'tclass')
+
+    # if the local-ip is not set, pick one from the interface !
+    # hopefully there is only one, otherwise it will not be very deterministic
+    # at time of writing the code currently returns ipv4 before ipv6 in the list
+
+    # XXX: There is no way to trigger an update of the interface source IP if
+    # XXX: the underlying interface IP address does change, I believe this
+    # XXX: limit/issue is present in vyatta too
+
+    if not options['local'] and options['dhcp-interface']:
+        # XXX: This behaviour changes from vyatta which would return 127.0.0.1 if
+        # XXX: the interface was not DHCP. As there is no easy way to find if an
+        # XXX: interface is using DHCP, and using this feature to get 127.0.0.1
+        # XXX: makes little sense, I feel the change in behaviour is acceptable
+        picked = get_interface_ip(options['dhcp-interface'])
+        if picked == '':
+            picked = '127.0.0.1'
+            print('Could not get an IP address from {dhcp-interface} using 127.0.0.1 instead')
+        options['local'] = picked
+        options['dhcp-interface'] = ''
+
+    # get interface addresses (currently effective) - to determine which
+    # address is no longer valid and needs to be removed
+    # could be done within ConfigurationState
+    eff_addr = conf.return_effective_values('address')
+    options['addresses-del'] = list_diff(eff_addr, options['addresses-add'])
+
+    # allmulticast fate is linked to multicast
+    options['allmulticast'] = options['multicast']
+
+    # check that per encapsulation all local-remote pairs are unique
+    conf.set_level('interfaces tunnel')
+    ct = conf.get_config_dict()['tunnel']
+    options['tunnel'] = {}
+
+    for name in ct:
+        tunnel = ct[name]
+        encap = tunnel.get('encapsulation', '')
+        local = tunnel.get('local-ip', '')
+        if not local:
+            local = get_interface_ip(tunnel.get('dhcp-interface', ''))
+        remote = tunnel.get('remote-ip', '<unset>')
+        pair = f'{local}-{remote}'
+        options['tunnel'][encap][pair] = options['tunnel'].setdefault(encap, {}).get(pair, 0) + 1
+
+    return conf.to_dict()
+
+
+def verify(conf):
+    options = conf['options']
+    changes = conf['changes']
+    actions = conf['actions']
+
+    ifname = options['ifname']
+    iftype = options['type']
+
+    if changes['section'] == 'delete':
+        if ifname in options['nhrp']:
+            raise ConfigError(f'Can not delete interface tunnel {iftype} {ifname}, it is used by nhrp')
+        # done, bail out early
+        return None
+
+    # tunnel encapsulation checks
+
+    if not iftype:
+        raise ConfigError(f'Must provide an "encapsulation" for tunnel {iftype} {ifname}')
+
+    if changes['type'] in ('modify', 'delete'):
+        # TODO: we could now deal with encapsulation modification by deleting / recreating
+        raise ConfigError(f'Encapsulation can only be set at tunnel creation for tunnel {iftype} {ifname}')
+
+    if iftype != 'sit' and options['6rd-prefix']:
+        # XXX: should be able to remove this and let the definition catch it
+        print(f'6RD can only be configured for sit interfaces not tunnel {iftype} {ifname}')
+
+    # what are the tunnel options we can set / modified / deleted
+
+    kls = get_class(options)
+    valid = kls.updates + ['alias', 'addresses-add', 'addresses-del']
+
+    if changes['section'] == 'create':
+        valid.extend(['type',])
+        valid.extend([o for o in kls.options if o not in kls.updates])
+
+    for create in actions['create']:
+        if create not in valid:
+            raise ConfigError(f'Can not set "{create}" for tunnel {iftype} {ifname} at tunnel creation')
+
+    for modify in actions['modify']:
+        if modify not in kls.updates:
+            raise ConfigError(f'Can not modify "{modify}" for tunnel {iftype} {ifname}. it must be set at tunnel creation')
+
+    for delete in actions['delete']:
+        if delete in kls.required:
+            raise ConfigError(f'Can not remove "{delete}", it is an mandatory option for tunnel {iftype} {ifname}')
+
+    # tunnel information
+
+    tun_local = options['local']
+    afi_local = get_afi(tun_local)
+    tun_remote = options['remote'] or tun_local
+    afi_remote = get_afi(tun_remote)
+    tun_ismgre = iftype == 'gre' and not options['remote']
+    tun_is6rd = iftype == 'sit' and options['6rd-prefix']
+
+    # incompatible options
+
+    if not tun_local and not options['dhcp-interface'] and not tun_is6rd:
+        raise ConfigError(f'Must configure either local-ip or dhcp-interface for tunnel {iftype} {ifname}')
+
+    if tun_local and options['dhcp-interface']:
+        raise ConfigError(f'Must configure only one of local-ip or dhcp-interface for tunnel {iftype} {ifname}')
+
+    # tunnel endpoint
+
+    if afi_local != afi_remote:
+        raise ConfigError(f'IPv4/IPv6 mismatch between local-ip and remote-ip for tunnel {iftype} {ifname}')
+
+    if afi_local != kls.tunnel:
+        version = 4 if tun_local == IP4 else 6
+        raise ConfigError(f'Invalid IPv{version} local-ip for tunnel {iftype} {ifname}')
+
+    ipv4_count = len([ip for ip in options['addresses-add'] if is_ipv4(ip)])
+    ipv6_count = len([ip for ip in options['addresses-add'] if is_ipv6(ip)])
+
+    if tun_ismgre and afi_local == IP6:
+        raise ConfigError(f'Using an IPv6 address is forbidden for mGRE tunnels such as tunnel {iftype} {ifname}')
+
+    # check address family use
+    # checks are not enforced (but ip command failing) for backward compatibility
+
+    if ipv4_count and not IP4 in kls.ip:
+        print(f'Should not use IPv4 addresses on tunnel {iftype} {ifname}')
+
+    if ipv6_count and not IP6 in kls.ip:
+        print(f'Should not use IPv6 addresses on tunnel {iftype} {ifname}')
+
+    # tunnel encapsulation check
+
+    convert = {
+        (6, 4, 'gre'):  'ip6gre',
+        (6, 6, 'gre'):  'ip6gre',
+        (4, 6, 'ipip'): 'ipip6',
+        (6, 6, 'ipip'): 'ip6ip6',
+    }
+
+    iprotos = []
+    if ipv4_count:
+        iprotos.append(4)
+    if ipv6_count:
+        iprotos.append(6)
+
+    for iproto in iprotos:
+        replace  = convert.get((kls.tunnel, iproto, iftype), '')
+        if replace:
+            raise ConfigError(
+                f'Using IPv6 address in local-ip or remote-ip is not possible with "encapsulation {iftype}". ' +
+                f'Use "encapsulation {replace}" for tunnel {iftype} {ifname} instead.'
+            )
+
+    # tunnel options
+
+    incompatible = []
+    if afi_local == IP6:
+        incompatible.extend(['ttl', 'tos', 'key',])
+    if afi_local == IP4:
+        incompatible.extend(['encaplimit', 'flowlabel', 'hoplimit', 'tclass'])
+
+    for option in incompatible:
+        if option in options:
+            # TODO: raise converted to print as not enforced by vyatta
+            # raise ConfigError(f'{option} is not valid for tunnel {iftype} {ifname}')
+            print(f'Using "{option}" is invalid for tunnel {iftype} {ifname}')
+
+    # duplicate tunnel pairs
+
+    pair = '{}-{}'.format(options['local'], options['remote'])
+    if options['tunnel'].get(iftype, {}).get(pair, 0) > 1:
+        raise ConfigError(f'More than one tunnel configured for with the same encapulation and IPs for tunnel {iftype} {ifname}')
+
+    return None
+
+
+def generate(gre):
+    return None
+
+def apply(conf):
+    options = conf['options']
+    changes = conf['changes']
+    actions = conf['actions']
+    kls = get_class(options)
+
+    # extract ifname as otherwise it is duplicated on the interface creation
+    ifname = options.pop('ifname')
+
+    # only the valid keys for creation of a Interface
+    config = dict((k, options[k]) for k in kls.options if options[k])
+
+    # setup or create the tunnel interface if it does not exist
+    tunnel = kls(ifname, **config)
+
+    if changes['section'] == 'delete':
+        tunnel.remove()
+        # The perl code was calling/opt/vyatta/sbin/vyatta-tunnel-cleanup
+        # which identified tunnels type which were not used anymore to remove them
+        # (ie: gre0, gretap0, etc.) The perl code did however nothing
+        # This feature is also not implemented yet
+        return
+
+    # A GRE interface without remote will be mGRE
+    # if the interface does not suppor the option, it skips the change
+    for option in tunnel.updates:
+        if changes['section'] in 'create' and option in tunnel.options:
+            # it was setup at creation
+            continue
+        tunnel.set_interface(option, options[option])
+
+    # set other interface properties
+    for option in ('alias', 'mtu', 'link_detect', 'multicast', 'allmulticast'):
+        tunnel.set_interface(option, options[option])
+
+    # Configure interface address(es)
+    for addr in options['addresses-del']:
+        tunnel.del_addr(addr)
+    for addr in options['addresses-add']:
+        tunnel.add_addr(addr)
+
+    # now bring it up (or not)
+    tunnel.set_state(options['state'])
+
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)