ipv6: migrate 'system ipv6' subsystem to XML/Python

2 files changed, 194 insertions, 0 deletions

diff --git a/interface-definitions/system-ipv6.xml.in b/interface-definitions/system-ipv6.xml.in
new file mode 100644
index 000000000..623418100
--- /dev/null
+++ b/interface-definitions/system-ipv6.xml.in
@@ -0,0 +1,70 @@
+<?xml version="1.0"?>
+<interfaceDefinition>
+  <node name="system">
+    <children>
+      <node name="ipv6" owner="${vyos_conf_scripts_dir}/system-ipv6.py">
+        <properties>
+          <help>IPv6 Settings</help>
+          <priority>290</priority>
+        </properties>
+        <children>
+          <leafNode name="blacklist">
+            <properties>
+              <help>Prevent IPv6 Kernel Module from being loaded</help>
+              <valueless/>
+            </properties>
+          </leafNode>
+          <leafNode name="disable-forwarding">
+            <properties>
+              <help>Disable IPv6 forwarding on all interfaces</help>
+              <valueless/>
+            </properties>
+          </leafNode>
+          <leafNode name="disable">
+            <properties>
+              <help>Disable assignment of IPv6 addresses on all interfaces</help>
+              <valueless/>
+            </properties>
+          </leafNode>
+          <node name="multipath">
+            <properties>
+              <help>IPv4 multipath settings</help>
+            </properties>
+            <children>
+              <leafNode name="layer4-hashing">
+                <properties>
+                  <help>Use layer 4 information for ECMP hashing</help>
+                  <valueless/>
+                </properties>
+              </leafNode>
+            </children>
+          </node>
+          <node name="neighbor">
+            <properties>
+              <help>Parameters for Neighbor cache</help>
+            </properties>
+            <children>
+              <leafNode name="table-size">
+                <properties>
+                  <help>Maximum number of entries to keep in the Neighbor cache</help>
+                  <completionHelp>
+                    <list>1024 2048 4096 8192 16384 32768</list>
+                  </completionHelp>
+                  <constraint>
+                    <regex>(1024|2048|4096|8192|16384|32768)</regex>
+                  </constraint>
+                </properties>
+              </leafNode>
+            </children>
+          </node>
+          <leafNode name="strict-dad">
+            <properties>
+              <help>Disable IPv6 operation on interface when DAD fails on LL addr</help>
+              <valueless/>
+            </properties>
+          </leafNode>
+        </children>
+      </node>
+    </children>
+  </node>
+</interfaceDefinition>
diff --git a/src/conf_mode/system-ipv6.py b/src/conf_mode/system-ipv6.py
new file mode 100755
index 000000000..a39d00f9f
--- /dev/null
+++ b/src/conf_mode/system-ipv6.py
@@ -0,0 +1,124 @@
+#!/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 sys
+
+from sys import exit
+from copy import deepcopy
+from vyos.config import Config
+from vyos import ConfigError
+
+ipv6_blacklist_file = '/etc/modprobe.d/vyos_blacklist_ipv6.conf'
+ipv6_disable_file = '/etc/modprobe.d/vyos_disable_ipv6.conf'
+
+default_config_data = {
+    'blacklist': False,
+    'reboot_message': False,
+    'ipv6_forward': '1',
+    'disable_addr_assignment': False,
+    'mp_layer4_hashing': '0',
+    'neighbor_cache': 8192,
+    'strict_dad': '1'
+
+}
+
+def sysctl(name, value):
+    os.system('sysctl -wq {}={}'.format(name, value))
+
+def get_config():
+    ip_opt = deepcopy(default_config_data)
+    conf = Config()
+    conf.set_level('system ipv6')
+    if conf.exists(''):
+        ip_opt['blacklist'] = conf.exists('blacklist')
+        if conf.exists_effective('blacklist') != conf.exists('blacklist'):
+            ip_opt['reboot_message'] = True
+
+        ip_opt['disable_addr_assignment'] = conf.exists('disable')
+        if conf.exists_effective('disable') != conf.exists('disable'):
+            ip_opt['reboot_message'] = True
+
+        if conf.exists('disable-forwarding'):
+            ip_opt['ipv6_forward'] = '0'
+
+        if conf.exists('multipath layer4-hashing'):
+            ip_opt['mp_layer4_hashing'] = '1'
+
+        if conf.exists('neighbor table-size'):
+            ip_opt['neighbor_cache'] = int(conf.return_value('neighbor table-size'))
+
+        if conf.exists('strict-dad'):
+            ip_opt['strict_dad'] = 2
+
+    return ip_opt
+
+def verify(ip_opt):
+    pass
+
+def generate(ip_opt):
+    pass
+
+def apply(ip_opt):
+    # disable IPv6 kernel module
+    if ip_opt['blacklist']:
+        with open(ipv6_blacklist_file, 'w') as f:
+            f.write('blacklist ipv6')
+    else:
+        if os.path.exists(ipv6_blacklist_file):
+            os.unlink(ipv6_blacklist_file)
+
+    # disable IPv6 address assignment
+    if ip_opt['disable_addr_assignment']:
+        with open(ipv6_disable_file, 'w') as f:
+            f.write('options ipv6 disable_ipv6=1')
+    else:
+        if os.path.exists(ipv6_disable_file):
+            os.unlink(ipv6_disable_file)
+
+    if ip_opt['reboot_message']:
+        print('Changing IPv6 blacklist/disable parameter will only take affect\n' \
+              'when the system is rebooted.')
+
+    # configure multipath
+    sysctl('net.ipv6.fib_multipath_hash_policy', ip_opt['mp_layer4_hashing'])
+
+    # apply neighbor table threshold values
+    sysctl('net.ipv6.neigh.default.gc_thresh3', ip_opt['neighbor_cache'])
+    sysctl('net.ipv6.neigh.default.gc_thresh2', ip_opt['neighbor_cache'] // 2)
+    sysctl('net.ipv6.neigh.default.gc_thresh1', ip_opt['neighbor_cache'] // 8)
+
+    # enable/disable IPv6 forwarding
+    with open('/proc/sys/net/ipv6/conf/all/forwarding', 'w') as f:
+        f.write(ip_opt['ipv6_forward'])
+
+    # configure IPv6 strict-dad
+    for root, dirs, files in os.walk('/proc/sys/net/ipv6/conf'):
+        for name in files:
+            if name == "accept_dad":
+                print(os.path.join(root, name))
+                with open(os.path.join(root, name), 'w') as f:
+                    f.write(str(ip_opt['strict_dad']))
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)