T5474: establish common file name pattern for XML conf mode commands

We will use _ as CLI level divider. The XML definition filename and also
the Python helper should match the CLI node.

Example:
set interfaces ethernet -> interfaces_ethernet.xml.in
set interfaces bond -> interfaces_bond.xml.in
set service dhcp-server -> service_dhcp-server-xml.in

(cherry picked from commit 4ef110fd2c501b718344c72d495ad7e16d2bd465)

1 files changed, 224 insertions, 0 deletions

diff --git a/src/conf_mode/interfaces_tunnel.py b/src/conf_mode/interfaces_tunnel.py
new file mode 100755
index 000000000..91aed9cc3
--- /dev/null
+++ b/src/conf_mode/interfaces_tunnel.py
@@ -0,0 +1,224 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2018-2022 yOS 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
+
+from sys import exit
+from netifaces import interfaces
+
+from vyos.config import Config
+from vyos.configdict import get_interface_dict
+from vyos.configdict import is_node_changed
+from vyos.configverify import verify_address
+from vyos.configverify import verify_bridge_delete
+from vyos.configverify import verify_interface_exists
+from vyos.configverify import verify_mtu_ipv6
+from vyos.configverify import verify_mirror_redirect
+from vyos.configverify import verify_vrf
+from vyos.configverify import verify_tunnel
+from vyos.configverify import verify_bond_bridge_member
+from vyos.ifconfig import Interface
+from vyos.ifconfig import Section
+from vyos.ifconfig import TunnelIf
+from vyos.utils.network import get_interface_config
+from vyos.utils.dict import dict_search
+from vyos import ConfigError
+from vyos import airbag
+airbag.enable()
+
+def get_config(config=None):
+    """
+    Retrive CLI config as dictionary. Dictionary can never be empty, as at least
+    the interface name will be added or a deleted flag
+    """
+    if config:
+        conf = config
+    else:
+        conf = Config()
+    base = ['interfaces', 'tunnel']
+    ifname, tunnel = get_interface_dict(conf, base)
+
+    if 'deleted' not in tunnel:
+        tmp = is_node_changed(conf, base + [ifname, 'encapsulation'])
+        if tmp: tunnel.update({'encapsulation_changed': {}})
+
+        tmp = is_node_changed(conf, base + [ifname, 'parameters', 'ip', 'key'])
+        if tmp: tunnel.update({'key_changed': {}})
+
+        # We also need to inspect other configured tunnels as there are Kernel
+        # restrictions where we need to comply. E.g. GRE tunnel key can't be used
+        # twice, or with multiple GRE tunnels to the same location we must specify
+        # a GRE key
+        conf.set_level(base)
+        tunnel['other_tunnels'] = conf.get_config_dict([], key_mangling=('-', '_'),
+                                                      get_first_key=True,
+                                                      no_tag_node_value_mangle=True)
+        # delete our own instance from this dict
+        ifname = tunnel['ifname']
+        del tunnel['other_tunnels'][ifname]
+        # if only one tunnel is present on the system, no need to keep this key
+        if len(tunnel['other_tunnels']) == 0:
+            del tunnel['other_tunnels']
+
+    # We must check if our interface is configured to be a DMVPN member
+    nhrp_base = ['protocols', 'nhrp', 'tunnel']
+    conf.set_level(nhrp_base)
+    nhrp = conf.get_config_dict([], key_mangling=('-', '_'), get_first_key=True)
+    if nhrp: tunnel.update({'nhrp' : list(nhrp.keys())})
+
+    if 'encapsulation' in tunnel and tunnel['encapsulation'] not in ['erspan', 'ip6erspan']:
+        del tunnel['parameters']['erspan']
+
+    return tunnel
+
+def verify(tunnel):
+    if 'deleted' in tunnel:
+        verify_bridge_delete(tunnel)
+
+        if 'nhrp' in tunnel and tunnel['ifname'] in tunnel['nhrp']:
+            raise ConfigError('Tunnel used for NHRP, it can not be deleted!')
+
+        return None
+
+    verify_tunnel(tunnel)
+
+    if tunnel['encapsulation'] in ['erspan', 'ip6erspan']:
+        if dict_search('parameters.ip.key', tunnel) == None:
+            raise ConfigError('ERSPAN requires ip key parameter!')
+
+        # this is a default field
+        ver = int(tunnel['parameters']['erspan']['version'])
+        if ver == 1:
+            if 'hw_id' in tunnel['parameters']['erspan']:
+                raise ConfigError('ERSPAN version 1 does not support hw-id!')
+            if 'direction' in tunnel['parameters']['erspan']:
+                raise ConfigError('ERSPAN version 1 does not support direction!')
+        elif ver == 2:
+            if 'idx' in tunnel['parameters']['erspan']:
+                raise ConfigError('ERSPAN version 2 does not index parameter!')
+            if 'direction' not in tunnel['parameters']['erspan']:
+                raise ConfigError('ERSPAN version 2 requires direction to be set!')
+
+    # If tunnel source is any and gre key is not set
+    interface = tunnel['ifname']
+    if tunnel['encapsulation'] in ['gre'] and \
+       dict_search('source_address', tunnel) == '0.0.0.0' and \
+       dict_search('parameters.ip.key', tunnel) == None:
+        raise ConfigError(f'"parameters ip key" must be set for {interface} when '\
+                           'encapsulation is GRE!')
+
+    gre_encapsulations = ['gre', 'gretap']
+    if tunnel['encapsulation'] in gre_encapsulations and 'other_tunnels' in tunnel:
+        # Check pairs tunnel source-address/encapsulation/key with exists tunnels.
+        # Prevent the same key for 2 tunnels with same source-address/encap. T2920
+        for o_tunnel, o_tunnel_conf in tunnel['other_tunnels'].items():
+            # no match on encapsulation - bail out
+            our_encapsulation = tunnel['encapsulation']
+            their_encapsulation = o_tunnel_conf['encapsulation']
+            if our_encapsulation in gre_encapsulations and their_encapsulation \
+                not in gre_encapsulations:
+                continue
+
+            our_address = dict_search('source_address', tunnel)
+            our_key = dict_search('parameters.ip.key', tunnel)
+            their_address = dict_search('source_address', o_tunnel_conf)
+            their_key = dict_search('parameters.ip.key', o_tunnel_conf)
+            if our_key != None:
+                if their_address == our_address and their_key == our_key:
+                    raise ConfigError(f'Key "{our_key}" for source-address "{our_address}" ' \
+                                      f'is already used for tunnel "{o_tunnel}"!')
+            else:
+                our_source_if = dict_search('source_interface', tunnel)
+                their_source_if = dict_search('source_interface', o_tunnel_conf)
+                our_remote = dict_search('remote', tunnel)
+                their_remote = dict_search('remote', o_tunnel_conf)
+                # If no IP GRE key is defined we can not have more then one GRE tunnel
+                # bound to any one interface/IP address and the same remote. This will
+                # result in a OS  PermissionError: add tunnel "gre0" failed: File exists
+                if (their_address == our_address or our_source_if == their_source_if) and \
+                    our_remote == their_remote:
+                    raise ConfigError(f'Missing required "ip key" parameter when '\
+                                       'running more then one GRE based tunnel on the '\
+                                       'same source-interface/source-address')
+
+    # Keys are not allowed with ipip and sit tunnels
+    if tunnel['encapsulation'] in ['ipip', 'sit']:
+        if dict_search('parameters.ip.key', tunnel) != None:
+            raise ConfigError('Keys are not allowed with ipip and sit tunnels!')
+
+    verify_mtu_ipv6(tunnel)
+    verify_address(tunnel)
+    verify_vrf(tunnel)
+    verify_bond_bridge_member(tunnel)
+    verify_mirror_redirect(tunnel)
+
+    if 'source_interface' in tunnel:
+        verify_interface_exists(tunnel['source_interface'])
+
+    # TTL != 0 and nopmtudisc are incompatible, parameters and ip use default
+    # values, thus the keys are always present.
+    if dict_search('parameters.ip.no_pmtu_discovery', tunnel) != None:
+        if dict_search('parameters.ip.ttl', tunnel) != '0':
+            raise ConfigError('Disabled PMTU requires TTL set to "0"!')
+        if tunnel['encapsulation'] in ['ipip6', 'ip6ip6', 'ip6gre']:
+            raise ConfigError('Can not disable PMTU discovery for given encapsulation')
+
+    if dict_search('parameters.ip.ignore_df', tunnel) != None:
+        if tunnel['encapsulation'] not in ['gretap']:
+            raise ConfigError('Option ignore-df can only be used on GRETAP tunnels!')
+
+        if dict_search('parameters.ip.no_pmtu_discovery', tunnel) == None:
+            raise ConfigError('Option ignore-df requires path MTU discovery to be disabled!')
+
+
+def generate(tunnel):
+    return None
+
+def apply(tunnel):
+    interface = tunnel['ifname']
+    # If a gretap tunnel is already existing we can not "simply" change local or
+    # remote addresses. This returns "Operation not supported" by the Kernel.
+    # There is no other solution to destroy and recreate the tunnel.
+    encap = ''
+    remote = ''
+    tmp = get_interface_config(interface)
+    if tmp:
+        encap = dict_search('linkinfo.info_kind', tmp)
+        remote = dict_search('linkinfo.info_data.remote', tmp)
+
+    if ('deleted' in tunnel or 'encapsulation_changed' in tunnel or encap in
+        ['gretap', 'ip6gretap', 'erspan', 'ip6erspan'] or remote in ['any'] or
+        'key_changed' in tunnel):
+        if interface in interfaces():
+            tmp = Interface(interface)
+            tmp.remove()
+        if 'deleted' in tunnel:
+            return None
+
+    tun = TunnelIf(**tunnel)
+    tun.update(tunnel)
+
+    return None
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        generate(c)
+        verify(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)