T6258: Add sysctl base-reachable-time for IPv6

Add abiilty to change `base_reachable_time_ms` option
/proc/sys/net/ipv6/neigh/{ifname}/base_reachable_time_ms

(cherry picked from commit 0bf4b570fe2d239b9fbabd3ae801ad3f04a06bde)

1 files changed, 27 insertions, 1 deletions

diff --git a/python/vyos/ifconfig/interface.py b/python/vyos/ifconfig/interface.py
index 6710cdbb0..f295c1066 100644
--- a/python/vyos/ifconfig/interface.py
+++ b/python/vyos/ifconfig/interface.py
@@ -1,4 +1,4 @@
-# Copyright 2019-2023 VyOS maintainers and contributors <maintainers@vyos.io>
+# Copyright 2019-2024 VyOS maintainers and contributors <maintainers@vyos.io>
 #
 # This library is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -194,6 +194,9 @@ class Interface(Control):
             'validate': assert_positive,
             'location': '/proc/sys/net/ipv6/conf/{ifname}/dad_transmits',
         },
+        'ipv6_cache_tmo': {
+            'location': '/proc/sys/net/ipv6/neigh/{ifname}/base_reachable_time_ms',
+        },
         'path_cost': {
             # XXX: we should set a maximum
             'validate': assert_positive,
@@ -262,6 +265,9 @@ class Interface(Control):
         'ipv6_dad_transmits': {
             'location': '/proc/sys/net/ipv6/conf/{ifname}/dad_transmits',
         },
+        'ipv6_cache_tmo': {
+            'location': '/proc/sys/net/ipv6/neigh/{ifname}/base_reachable_time_ms',
+        },
         'proxy_arp': {
             'location': '/proc/sys/net/ipv4/conf/{ifname}/proxy_arp',
         },
@@ -603,6 +609,21 @@ class Interface(Control):
             return None
         return self.set_interface('arp_cache_tmo', tmo)
 
+    def set_ipv6_cache_tmo(self, tmo):
+        """
+        Set IPv6 cache timeout value in seconds. Internal Kernel representation
+        is in milliseconds.
+
+        Example:
+        >>> from vyos.ifconfig import Interface
+        >>> Interface('eth0').set_ipv6_cache_tmo(40)
+        """
+        tmo = str(int(tmo) * 1000)
+        tmp = self.get_interface('ipv6_cache_tmo')
+        if tmp == tmo:
+            return None
+        return self.set_interface('ipv6_cache_tmo', tmo)
+
     def _cleanup_mss_rules(self, table, ifname):
         commands = []
         results = self._cmd(f'nft -a list chain {table} VYOS_TCP_MSS').split("\n")
@@ -1656,6 +1677,11 @@ class Interface(Control):
             for addr in tmp:
                 self.add_ipv6_eui64_address(addr)
 
+        # Configure IPv6 base time in milliseconds - has default value
+        tmp = dict_search('ipv6.base_reachable_time', config)
+        value = tmp if (tmp != None) else '30'
+        self.set_ipv6_cache_tmo(value)
+
         # re-add ourselves to any bridge we might have fallen out of
         if 'is_bridge_member' in config:
             tmp = config.get('is_bridge_member')