ipv6: T5464: add support for per-interface dad (duplicate address detection) setting

4 files changed, 53 insertions, 2 deletions

diff --git a/interface-definitions/include/interface/ipv6-accept-dad.xml.i b/interface-definitions/include/interface/ipv6-accept-dad.xml.i
new file mode 100644
index 000000000..7554b270a
--- /dev/null
+++ b/interface-definitions/include/interface/ipv6-accept-dad.xml.i
@@ -0,0 +1,20 @@
+<!-- include start from interface/ipv6-accept-dad.xml.i -->
+<leafNode name="accept-dad">
+  <properties>
+    <help>Accept Duplicate Address Detection</help>
+    <valueHelp>
+      <format>0</format>
+      <description>Disable DAD</description>
+    </valueHelp>
+    <valueHelp>
+      <format>1</format>
+      <description>Enable DAD</description>
+    </valueHelp>
+    <valueHelp>
+      <format>2</format>
+      <description>Enable DAD - disable IPv6 if MAC-based duplicate link-local address found</description>
+    </valueHelp>
+  </properties>
+  <defaultValue>1</defaultValue>
+</leafNode>
+<!-- include end -->
diff --git a/interface-definitions/include/interface/ipv6-options.xml.i b/interface-definitions/include/interface/ipv6-options.xml.i
index f740ce0c2..d2e47de91 100644
--- a/interface-definitions/include/interface/ipv6-options.xml.i
+++ b/interface-definitions/include/interface/ipv6-options.xml.i
@@ -6,6 +6,7 @@
   <children>
     #include <include/interface/adjust-mss.xml.i>
     #include <include/interface/disable-forwarding.xml.i>
+    #include <include/interface/ipv6-accept-dad.xml.i>
     #include <include/interface/ipv6-address.xml.i>
     #include <include/interface/ipv6-dup-addr-detect-transmits.xml.i>
   </children>
diff --git a/python/vyos/ifconfig/interface.py b/python/vyos/ifconfig/interface.py
index 6e85b7a9d..cc6149428 100644
--- a/python/vyos/ifconfig/interface.py
+++ b/python/vyos/ifconfig/interface.py
@@ -191,6 +191,10 @@ class Interface(Control):
             'validate': lambda fwd: assert_range(fwd,0,2),
             'location': '/proc/sys/net/ipv6/conf/{ifname}/forwarding',
         },
+        'ipv6_accept_dad': {
+            'validate': lambda dad: assert_range(dad,0,3),
+            'location': '/proc/sys/net/ipv6/conf/{ifname}/accept_dad',
+        },
         'ipv6_dad_transmits': {
             'validate': assert_positive,
             'location': '/proc/sys/net/ipv6/conf/{ifname}/dad_transmits',
@@ -256,6 +260,9 @@ class Interface(Control):
         'ipv6_forwarding': {
             'location': '/proc/sys/net/ipv6/conf/{ifname}/forwarding',
         },
+        'ipv6_accept_dad': {
+            'location': '/proc/sys/net/ipv6/conf/{ifname}/accept_dad',
+        },
         'ipv6_dad_transmits': {
             'location': '/proc/sys/net/ipv6/conf/{ifname}/dad_transmits',
         },
@@ -846,6 +853,13 @@ class Interface(Control):
             return None
         return self.set_interface('ipv6_forwarding', forwarding)
 
+    def set_ipv6_dad_accept(self, dad):
+        """Whether to accept DAD (Duplicate Address Detection)"""
+        tmp = self.get_interface('ipv6_accept_dad')
+        if tmp == dad:
+            return None
+        return self.set_interface('ipv6_accept_dad', dad)
+
     def set_ipv6_dad_messages(self, dad):
         """
         The amount of Duplicate Address Detection probes to send.
@@ -1551,9 +1565,17 @@ class Interface(Control):
         value = '1' if (tmp != None) else '0'
         self.set_ipv6_autoconf(value)
 
-        # IPv6 Duplicate Address Detection (DAD) tries
+        # Whether to accept IPv6 DAD (Duplicate Address Detection) packets
+        tmp = dict_search('ipv6.accept_dad', config)
+        # Not all interface types got this CLI option, but if they do, there
+        # is an XML defaultValue available
+        if (tmp != None): self.set_ipv6_dad_accept(tmp)
+
+        # IPv6 DAD tries
         tmp = dict_search('ipv6.dup_addr_detect_transmits', config)
-        self.set_ipv6_dad_messages(tmp)
+        # Not all interface types got this CLI option, but if they do, there
+        # is an XML defaultValue available
+        if (tmp != None): self.set_ipv6_dad_messages(tmp)
 
         # Delete old IPv6 EUI64 addresses before changing MAC
         for addr in (dict_search('ipv6.address.eui64_old', config) or []):
diff --git a/smoketest/scripts/cli/base_interfaces_test.py b/smoketest/scripts/cli/base_interfaces_test.py
index cef61e42b..b5b65e253 100644
--- a/smoketest/scripts/cli/base_interfaces_test.py
+++ b/smoketest/scripts/cli/base_interfaces_test.py
@@ -843,6 +843,7 @@ class BasicInterfaceTest:
 
             mss = '1400'
             dad_transmits = '10'
+            accept_dad = '0'
 
             for interface in self._interfaces:
                 path = self._base_path + [interface]
@@ -853,6 +854,9 @@ class BasicInterfaceTest:
                 if cli_defined(self._base_path + ['ipv6'], 'adjust-mss'):
                     self.cli_set(path + ['ipv6', 'adjust-mss', mss])
 
+                if cli_defined(self._base_path + ['ipv6'], 'accept-dad'):
+                    self.cli_set(path + ['ipv6', 'accept-dad', accept_dad])
+
                 if cli_defined(self._base_path + ['ipv6'], 'dup-addr-detect-transmits'):
                     self.cli_set(path + ['ipv6', 'dup-addr-detect-transmits', dad_transmits])
 
@@ -870,6 +874,10 @@ class BasicInterfaceTest:
                         if line.startswith(base_options):
                             self.assertIn(f'tcp option maxseg size set {mss}', line)
 
+                if cli_defined(self._base_path + ['ipv6'], 'accept-dad'):
+                    tmp = read_file(f'{proc_base}/accept_dad')
+                    self.assertEqual(accept_dad, tmp)
+
                 if cli_defined(self._base_path + ['ipv6'], 'dup-addr-detect-transmits'):
                     tmp = read_file(f'{proc_base}/dad_transmits')
                     self.assertEqual(dad_transmits, tmp)