keepalived: T4109: Add high-availability virtual-server

Add new feature, high-availability virtual-server
Change XML, python and templates
Move vrrp to root node 'high-availability' as all logic are
handler by root node 'high-availability'

1 files changed, 180 insertions, 0 deletions

diff --git a/src/conf_mode/high-availability.py b/src/conf_mode/high-availability.py
new file mode 100755
index 000000000..7d51bb393
--- /dev/null
+++ b/src/conf_mode/high-availability.py
@@ -0,0 +1,180 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2018-2022 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
+
+from sys import exit
+from ipaddress import ip_interface
+from ipaddress import IPv4Interface
+from ipaddress import IPv6Interface
+
+from vyos.config import Config
+from vyos.configdict import dict_merge
+from vyos.ifconfig.vrrp import VRRP
+from vyos.template import render
+from vyos.template import is_ipv4
+from vyos.template import is_ipv6
+from vyos.util import call
+from vyos.util import is_systemd_service_running
+from vyos.xml import defaults
+from vyos import ConfigError
+from vyos import airbag
+airbag.enable()
+
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
+
+    base = ['high-availability']
+    base_vrrp = ['high-availability', 'vrrp']
+    if not conf.exists(base):
+        return None
+
+    ha = conf.get_config_dict(base, key_mangling=('-', '_'),
+                                get_first_key=True, no_tag_node_value_mangle=True)
+    # We have gathered the dict representation of the CLI, but there are default
+    # options which we need to update into the dictionary retrived.
+    if 'vrrp' in ha:
+        if 'group' in ha['vrrp']:
+            default_values_vrrp = defaults(base_vrrp + ['group'])
+            for group in ha['vrrp']['group']:
+                ha['vrrp']['group'][group] = dict_merge(default_values_vrrp, ha['vrrp']['group'][group])
+
+    # Merge per virtual-server default values
+    if 'virtual_server' in ha:
+        default_values = defaults(base + ['virtual-server'])
+        for vs in ha['virtual_server']:
+            ha['virtual_server'][vs] = dict_merge(default_values, ha['virtual_server'][vs])
+
+    ## Get the sync group used for conntrack-sync
+    conntrack_path = ['service', 'conntrack-sync', 'failover-mechanism', 'vrrp', 'sync-group']
+    if conf.exists(conntrack_path):
+        ha['conntrack_sync_group'] = conf.return_value(conntrack_path)
+
+    return ha
+
+def verify(ha):
+    if not ha:
+        return None
+
+    used_vrid_if = []
+    if 'vrrp' in ha and 'group' in ha['vrrp']:
+        for group, group_config in ha['vrrp']['group'].items():
+            # Check required fields
+            if 'vrid' not in group_config:
+                raise ConfigError(f'VRID is required but not set in VRRP group "{group}"')
+
+            if 'interface' not in group_config:
+                raise ConfigError(f'Interface is required but not set in VRRP group "{group}"')
+
+            if 'address' not in group_config:
+                raise ConfigError(f'Virtual IP address is required but not set in VRRP group "{group}"')
+
+            if 'authentication' in group_config:
+                if not {'password', 'type'} <= set(group_config['authentication']):
+                    raise ConfigError(f'Authentication requires both type and passwortd to be set in VRRP group "{group}"')
+
+            # We can not use a VRID once per interface
+            interface = group_config['interface']
+            vrid = group_config['vrid']
+            tmp = {'interface': interface, 'vrid': vrid}
+            if tmp in used_vrid_if:
+                raise ConfigError(f'VRID "{vrid}" can only be used once on interface "{interface}"!')
+            used_vrid_if.append(tmp)
+
+            # Keepalived doesn't allow mixing IPv4 and IPv6 in one group, so we mirror that restriction
+
+            # XXX: filter on map object is destructive, so we force it to list.
+            # Additionally, filter objects always evaluate to True, empty or not,
+            # so we force them to lists as well.
+            vaddrs = list(map(lambda i: ip_interface(i), group_config['address']))
+            vaddrs4 = list(filter(lambda x: isinstance(x, IPv4Interface), vaddrs))
+            vaddrs6 = list(filter(lambda x: isinstance(x, IPv6Interface), vaddrs))
+
+            if vaddrs4 and vaddrs6:
+                raise ConfigError(f'VRRP group "{group}" mixes IPv4 and IPv6 virtual addresses, this is not allowed.\n' \
+                                  'Create individual groups for IPv4 and IPv6!')
+            if vaddrs4:
+                if 'hello_source_address' in group_config:
+                    if is_ipv6(group_config['hello_source_address']):
+                        raise ConfigError(f'VRRP group "{group}" uses IPv4 but hello-source-address is IPv6!')
+
+                if 'peer_address' in group_config:
+                    if is_ipv6(group_config['peer_address']):
+                        raise ConfigError(f'VRRP group "{group}" uses IPv4 but peer-address is IPv6!')
+
+            if vaddrs6:
+                if 'hello_source_address' in group_config:
+                    if is_ipv4(group_config['hello_source_address']):
+                        raise ConfigError(f'VRRP group "{group}" uses IPv6 but hello-source-address is IPv4!')
+
+                if 'peer_address' in group_config:
+                    if is_ipv4(group_config['peer_address']):
+                        raise ConfigError(f'VRRP group "{group}" uses IPv6 but peer-address is IPv4!')
+    # Check sync groups
+    if 'vrrp' in ha and 'sync_group' in ha['vrrp']:
+        for sync_group, sync_config in ha['vrrp']['sync_group'].items():
+            if 'member' in sync_config:
+                for member in sync_config['member']:
+                    if member not in ha['vrrp']['group']:
+                        raise ConfigError(f'VRRP sync-group "{sync_group}" refers to VRRP group "{member}", '\
+                                          'but it does not exist!')
+
+    # Virtual-server
+    if 'virtual_server' in ha:
+        for vs, vs_config in ha['virtual_server'].items():
+            if 'port' not in vs_config:
+                raise ConfigError(f'Port is required but not set for virtual-server "{vs}"')
+            if 'real_server' not in vs_config:
+                raise ConfigError(f'Real-server ip is required but not set for virtual-server "{vs}"')
+        # Real-server
+        for rs, rs_config in vs_config['real_server'].items():
+            if 'port' not in rs_config:
+                raise ConfigError(f'Port is required but not set for virtual-server "{vs}" real-server "{rs}"')
+
+
+def generate(ha):
+    if not ha:
+        return None
+
+    render(VRRP.location['config'], 'high-availability/keepalived.conf.tmpl', ha)
+    return None
+
+def apply(ha):
+    service_name = 'keepalived.service'
+    if not ha:
+        call(f'systemctl stop {service_name}')
+        return None
+
+    # XXX: T3944 - reload keepalived configuration if service is already running
+    # to not cause any service disruption when applying changes.
+    if is_systemd_service_running(service_name):
+        call(f'systemctl reload {service_name}')
+    else:
+        call(f'systemctl restart {service_name}')
+    return None
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)