1 files changed, 64 insertions, 0 deletions
diff --git a/src/migration-scripts/bgp/1-to-2 b/src/migration-scripts/bgp/1-to-2
new file mode 100644
index 0000000..c0fc3b0
--- /dev/null
+++ b/src/migration-scripts/bgp/1-to-2
@@ -0,0 +1,64 @@
+# Copyright 2021-2024 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
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+# T3741: no-ipv4-unicast is now enabled by default
+# T5937: Migrate IPv6 BGP Neighbor Peer Groups
+
+from vyos.configtree import ConfigTree
+
+base = ['protocols', 'bgp']
+
+def migrate(config: ConfigTree) -> None:
+    if not config.exists(base):
+        # Nothing to do
+        return
+
+    # This is now a default option - simply delete it.
+    # As it was configured explicitly - we can also bail out early as we need to
+    # do nothing!
+    if config.exists(base + ['parameters', 'default', 'no-ipv4-unicast']):
+        config.delete(base + ['parameters', 'default', 'no-ipv4-unicast'])
+
+        # Check if the "default" node is now empty, if so - remove it
+        if len(config.list_nodes(base + ['parameters', 'default'])) == 0:
+            config.delete(base + ['parameters', 'default'])
+
+        # Check if the "default" node is now empty, if so - remove it
+        if len(config.list_nodes(base + ['parameters'])) == 0:
+            config.delete(base + ['parameters'])
+    else:
+        # As we now install a new default option into BGP we need to migrate all
+        # existing BGP neighbors and restore the old behavior
+        if config.exists(base + ['neighbor']):
+            for neighbor in config.list_nodes(base + ['neighbor']):
+                peer_group = base + ['neighbor', neighbor, 'peer-group']
+                if config.exists(peer_group):
+                    peer_group_name = config.return_value(peer_group)
+                    # peer group enables old behavior for neighbor - bail out
+                    if config.exists(base + ['peer-group', peer_group_name, 'address-family', 'ipv4-unicast']):
+                        continue
+
+                afi_ipv4 = base + ['neighbor', neighbor, 'address-family', 'ipv4-unicast']
+                if not config.exists(afi_ipv4):
+                    config.set(afi_ipv4)
+
+    # Migrate IPv6 AFI peer-group
+    if config.exists(base + ['neighbor']):
+        for neighbor in config.list_nodes(base + ['neighbor']):
+            tmp_path = base + ['neighbor', neighbor, 'address-family', 'ipv6-unicast', 'peer-group']
+            if config.exists(tmp_path):
+                peer_group = config.return_value(tmp_path)
+                config.set(base + ['neighbor', neighbor, 'peer-group'], value=peer_group)
+                config.delete(tmp_path)