[PATCH pve-firewall v4 07/27] firewall: ipset: add option to handle dangling references on delete

[Arthur Bied-Charreton <a.bied-charreton@proxmox.com>]

Deleting an ipset referenced by rules or security groups leaves dangling
references, which the firewall fails to parse and drops.

Add a 'dangling-references' option to the delete endpoint, to either
'disable' the referencing rules or 'drop' them along with the ipset. The
default, 'keep', leaves them as they are. For cluster ipsets, this also
covers all downstream configs (host, guest and vnet).

Signed-off-by: Arthur Bied-Charreton <a.bied-charreton@proxmox.com>
---
 src/PVE/API2/Firewall/IPSet.pm | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/src/PVE/API2/Firewall/IPSet.pm b/src/PVE/API2/Firewall/IPSet.pm
index a6a44be..fe4f8c9 100644
--- a/src/PVE/API2/Firewall/IPSet.pm
+++ b/src/PVE/API2/Firewall/IPSet.pm
@@ -2,6 +2,7 @@ package PVE::API2::Firewall::IPSetBase;
 
 use strict;
 use warnings;
+use PVE::Firewall::References qw(update_refs);
 use PVE::Exception qw(raise raise_param_exc);
 use PVE::JSONSchema qw(get_standard_option);
 
@@ -140,6 +141,15 @@ sub register_delete_ipset {
         optional => 1,
         description => 'Delete all members of the IPSet, if there are any.',
     };
+    $properties->{'dangling-references'} = {
+        type => 'string',
+        enum => ['keep', 'disable', 'drop'],
+        optional => 1,
+        description =>
+            "Handle references that the deletion would leave dangling. Use 'disable' to disable "
+            . "the referencing rules, or 'drop' to remove them entirely.",
+        default => 'keep',
+    };
 
     $class->register_method({
         name => 'delete_ipset',
@@ -166,6 +176,17 @@ sub register_delete_ipset {
                     die "IPSet '$param->{name}' is not empty\n"
                         if scalar(@$ipset) && !$param->{force};
 
+                    my $action = $param->{'dangling-references'} // 'keep';
+
+                    update_refs({
+                        conf => $fw_conf,
+                        kind => 'ipset',
+                        old => $param->{name},
+                        env => $class->rule_env(),
+                        action => $action eq 'keep' ? undef : $action,
+                        subject => "ipset '$param->{name}' deleted",
+                    });
+
                     $class->save_ipset($param, $fw_conf, undef);
 
                 },
-- 
2.47.3