[PATCH pve-container v2 13/16] net: report veth plug and unplug to SDN with the hwaddr

[Hannes Laimer <h.laimer@proxmox.com>]

The SDN layer answers DHCP on a plugged interface from the mapping of
its guest NIC, and drops what it holds for the interface once it goes
away. So the veth delete reports through it. A bridge change keeps
pve-common's unplug, allocates on the new vnet and pushes through the
mapping call, whose push writes the dnsmasq reservation. The plug that
follows tells the SDN layer where the veth went and carries the
responder's record. A disconnected NIC tells it at its next plug. This
needs a libpve-network-perl with the SDN unplug when the package is
installed at all. pve-container keeps working without it, so the floor
is a Breaks on the older versions.

Signed-off-by: Hannes Laimer <h.laimer@proxmox.com>
---
 src/PVE/LXC.pm            | 24 ++++++++++++++++++++++--
 src/PVE/LXC/Config.pm     |  2 +-
 src/lxc-pve-poststop-hook |  5 ++---
 3 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/src/PVE/LXC.pm b/src/PVE/LXC.pm
index dee073d..62b76b4 100644
--- a/src/PVE/LXC.pm
+++ b/src/PVE/LXC.pm
@@ -1117,7 +1117,13 @@ sub net_tap_plug : prototype($$) {
 
     if ($have_sdn) {
         PVE::Network::SDN::Zones::tap_plug(
-            $iface, $bridge, $tag, $create_firewall_bridges, $trunks, $rate,
+            $iface,
+            $bridge,
+            $tag,
+            $create_firewall_bridges,
+            $trunks,
+            $rate,
+            { mac => $hwaddr },
         );
         PVE::Network::SDN::Zones::add_bridge_fdb($iface, $hwaddr, $bridge);
     } else {
@@ -1135,6 +1141,17 @@ sub net_tap_plug : prototype($$) {
     PVE::Tools::run_command(['/sbin/ip', 'link', 'set', 'dev', $iface, 'up']);
 }
 
+# the SDN layer drops what its DHCP backends hold for the veth, which may be gone already
+sub net_veth_delete : prototype($) {
+    my ($veth) = @_;
+
+    if ($have_sdn) {
+        PVE::Network::SDN::Zones::veth_delete($veth);
+    } else {
+        PVE::Network::veth_delete($veth);
+    }
+}
+
 sub update_net {
     my ($vmid, $conf, $opt, $newnet, $netid, $rootdir) = @_;
 
@@ -1154,7 +1171,7 @@ sub update_net {
             || safe_string_ne($oldnet->{name}, $newnet->{name})
         ) {
 
-            PVE::Network::veth_delete($veth);
+            PVE::LXC::net_veth_delete($veth);
 
             if ($have_sdn && safe_string_ne($oldnet->{hwaddr}, $newnet->{hwaddr})) {
                 eval {
@@ -1209,6 +1226,9 @@ sub update_net {
                     PVE::Network::SDN::Vnets::add_next_free_cidr(
                         $newnet->{bridge}, $conf->{hostname}, $newnet->{hwaddr}, $vmid, undef, 1,
                     );
+                    PVE::Network::SDN::Vnets::add_dhcp_mapping(
+                        $newnet->{bridge}, $newnet->{hwaddr}, $vmid, $conf->{hostname},
+                    );
                 }
                 eval { PVE::LXC::net_tap_plug($veth, $newnet) };
                 if (my $err = $@) {
diff --git a/src/PVE/LXC/Config.pm b/src/PVE/LXC/Config.pm
index 3eb1905..15ea6ea 100644
--- a/src/PVE/LXC/Config.pm
+++ b/src/PVE/LXC/Config.pm
@@ -1702,7 +1702,7 @@ sub vmconfig_hotplug_pending {
                 my $net = parse_lxc_network($conf->{$opt});
                 PVE::LXC::kill_dhclients($vmid, $net->{name}) if $net->{'host-managed'};
 
-                PVE::Network::veth_delete("veth${vmid}i$netid");
+                PVE::LXC::net_veth_delete("veth${vmid}i$netid");
                 if ($have_sdn) {
                     print "delete ips from $opt\n";
                     eval {
diff --git a/src/lxc-pve-poststop-hook b/src/lxc-pve-poststop-hook
index c8bbb79..aba6f4f 100755
--- a/src/lxc-pve-poststop-hook
+++ b/src/lxc-pve-poststop-hook
@@ -11,7 +11,6 @@ use PVE::GuestHelpers;
 use PVE::LXC::Config;
 use PVE::LXC::Tools;
 use PVE::LXC;
-use PVE::Network;
 use PVE::RESTEnvironment;
 use PVE::Storage;
 use PVE::Tools;
@@ -49,8 +48,8 @@ PVE::LXC::Tools::lxc_hook(
             my $ind = $1;
             my $net = PVE::LXC::Config->parse_lxc_network($conf->{$k});
             next if $net->{type} ne 'veth';
-            # veth_delete tests with '-d /sys/class/net/$name' before running the command
-            PVE::Network::veth_delete("veth${vmid}i$ind");
+            # reports the unplug and deletes the veth only where it still exists
+            PVE::LXC::net_veth_delete("veth${vmid}i$ind");
         }
 
         my $config_updated = 0;
-- 
2.47.3