From ca43693778e7c35cc41494a07109e3ea426a09c6 Mon Sep 17 00:00:00 2001
From: Julien Fortin <julien@cumulusnetworks.com>
Date: Thu, 6 Aug 2020 14:29:28 +0200
Subject: [PATCH] addons: vxlan: new attribute: vxlan-mcastgrp-map

"vxlan-mcastgrp-map": {
    "help": "vxlan multicast group for single-vxlan device",
    "validvals": ["<number-ipv4-list>"],
    "example": ["vxlan-mcastgrp-map 1000=239.1.1.100 1001=239.1.1.200"],
}

Signed-off-by: Julien Fortin <julien@cumulusnetworks.com>
---
 debian/changelog          |  1 +
 ifupdown2/addons/vxlan.py | 43 ++++++++++++++++++++++++++++++++++++++-
 ifupdown2/lib/iproute2.py | 27 ++++++++++++++++++++++++
 3 files changed, 70 insertions(+), 1 deletion(-)

diff --git a/debian/changelog b/debian/changelog
index bd9dec4..55e7701 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -5,6 +5,7 @@ ifupdown2 (3.0.0-1) unstable; urgency=medium
    * New: bridge-always-up attribute
    * New: set bridge mtu with policy default
    * New: ES bond with "es-sys-mac" attribute
+   * New: vxlan attribute: vxlan-mcastgrp-map
    * New: support for "veth-peer-name" attribute
    * New: dhcp policy: dhclient_retry_on_failure
    * New: support for marking interfaces as mgmt interfaces
diff --git a/ifupdown2/addons/vxlan.py b/ifupdown2/addons/vxlan.py
index b6f5b6f..8e96061 100644
--- a/ifupdown2/addons/vxlan.py
+++ b/ifupdown2/addons/vxlan.py
@@ -109,7 +109,12 @@ class vxlan(Addon, moduleBase):
                 "help": "vxlan multicast group",
                 "validvals": ["<ip6>"],
                 "example": ["vxlan-mcastgrp ff02::15c"],
-            }
+            },
+            "vxlan-mcastgrp-map": {
+                "help": "vxlan multicast group for single-vxlan device",
+                "validvals": ["<number-ipv4-list>"],
+                "example": ["vxlan-mcastgrp-map 1000=239.1.1.100 1001=239.1.1.200"],
+            },
         }
     }
 
@@ -816,6 +821,33 @@ class vxlan(Addon, moduleBase):
                             self.log_error("%s: vxlan creation failed: %s" % (ifname, str(e)), ifaceobj)
                         return
 
+        if ifaceobj.link_privflags & ifaceLinkPrivFlags.SINGLE_VXLAN:
+            # check current fdb entries
+            vxlan_fdb_data = utils.exec_command("bridge fdb show dev %s" % ifname)
+            current_fdb = []
+
+            if vxlan_fdb_data:
+                # each entry should look like the following:
+                # 00:00:00:00:00:00 dst 239.1.1.100 src_vni 1000 self permanent
+                for entry in [line for line in vxlan_fdb_data.strip().split("\n") if "src_vni" in line]:
+                    mac, _, dst, _, src_vni = entry.split()[0:5]
+                    current_fdb.append((mac, src_vni, dst))
+
+            user_config_fdb = self.get_vxlan_fdb_src_vni(ifaceobj.get_attr_value("vxlan-mcastgrp-map"))
+
+            fdb_to_remove = set(current_fdb) - set(user_config_fdb)
+
+            for mac, vni, _ in fdb_to_remove:
+                self.iproute2.bridge_fdb_del_src_vni(ifname, mac, vni)
+
+            for mac, src_vni, dst_ip in user_config_fdb:
+                if (mac, src_vni, dst_ip) not in current_fdb:
+                    try:
+                        self.iproute2.bridge_fdb_add_src_vni(ifname, src_vni, dst_ip)
+                    except Exception as e:
+                        ifaceobj.set_status(ifaceStatus.ERROR)
+                        self.log_error("%s: vxlan-mcastgrp-map: %s=%s: %s" % (ifname, src_vni, dst_ip, str(e)), raise_error=False)
+
         vxlan_purge_remotes = self.__get_vlxan_purge_remotes(ifaceobj)
 
         remoteips = ifaceobj.get_attr_value('vxlan-remoteip')
@@ -866,6 +898,15 @@ class vxlan(Addon, moduleBase):
                 except Exception:
                     pass
 
+    @staticmethod
+    def get_vxlan_fdb_src_vni(vxlan_mcast_grp_map):
+        fdbs = []
+        for entry in vxlan_mcast_grp_map or []:
+            for vni_ip in entry.split():
+                src_vni, dst_ip = vni_ip.split("=")
+                fdbs.append(("00:00:00:00:00:00", src_vni, dst_ip))
+        return fdbs
+
     def _down(self, ifaceobj):
         try:
             self.netlink.link_del(ifaceobj.name)
diff --git a/ifupdown2/lib/iproute2.py b/ifupdown2/lib/iproute2.py
index 2e810df..e4317b4 100644
--- a/ifupdown2/lib/iproute2.py
+++ b/ifupdown2/lib/iproute2.py
@@ -575,6 +575,21 @@ class IPRoute2(Cache, Requirements):
             )
         )
 
+    @staticmethod
+    def bridge_fdb_add_src_vni(dev, src_vni, dst_ip):
+        """
+            bridge fdb add dev $dev 00:00:00:00:00:00 src_vni $src_vni dst $dst_ip
+        """
+        utils.exec_command(
+            "%s fdb add dev %s 00:00:00:00:00:00 src_vni %s dst %s"
+            % (
+                utils.bridge_cmd,
+                dev,
+                src_vni,
+                dst_ip
+            )
+        )
+
     @staticmethod
     def bridge_fdb_append(dev, address, vlan=None, bridge=True, remote=None):
         target = "self" if bridge else ""
@@ -593,6 +608,18 @@ class IPRoute2(Cache, Requirements):
             )
         )
 
+    @staticmethod
+    def bridge_fdb_del_src_vni(dev, mac, src_vni):
+        utils.exec_command(
+            "%s fdb del %s dev %s src_vni %s"
+            % (
+                utils.bridge_cmd,
+                mac,
+                dev,
+                src_vni
+            )
+        )
+
     @staticmethod
     def bridge_fdb_del(dev, address, vlan=None, bridge=True, remote=None):
         target = "self" if bridge else ""