From 2c247d978754f060db2df4c265d7087d724f6215 Mon Sep 17 00:00:00 2001
From: Franco Fichtner <franco@opnsense.org>
Date: Thu, 21 Oct 2021 09:42:36 +0200
Subject: [PATCH] dhcp: support AdvRASrcAddress/AdvSourceLLAddress trickery

---
 src/etc/inc/plugins.inc.d/dhcpd.inc | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/etc/inc/plugins.inc.d/dhcpd.inc b/src/etc/inc/plugins.inc.d/dhcpd.inc
index 520a8e0be..2735ccfd9 100644
--- a/src/etc/inc/plugins.inc.d/dhcpd.inc
+++ b/src/etc/inc/plugins.inc.d/dhcpd.inc
@@ -308,6 +308,13 @@ function dhcpd_radvd_configure($verbose = false, $blacklist = array())
             $radvdconf .= "\tAdvDefaultLifetime 0;\n";
         }
 
+        if (is_linklocal($ifcfgipv6)) {
+            $radvdconf .= "\tAdvSourceLLAddress off;\n";
+            $radvdconf .= "\tAdvRASrcAddress{\n";
+            $radvdconf .= "\t\t{$ifcfgipv6};\n";
+            $radvdconf .= "\t}\n";
+        }
+
         $stanzas = array();
 
         list ($ifcfgipv6, $networkv6) = interfaces_primary_address6($dhcpv6if, $ifconfig_details);