dhcp-server: T2927: Add empty args if does not possible to determine variables

(cherry picked from commit 2f8b33a26e63e5b9ac4e697b9312f2238d6241f3)

2 files changed, 21 insertions, 22 deletions

diff --git a/data/templates/dhcp-server/dhcpd.conf.tmpl b/data/templates/dhcp-server/dhcpd.conf.tmpl
index a2d5cb242..d774b4827 100644
--- a/data/templates/dhcp-server/dhcpd.conf.tmpl
+++ b/data/templates/dhcp-server/dhcpd.conf.tmpl
@@ -8,16 +8,12 @@
 on release {
     set ClientName = pick-first-value(host-decl-name, option fqdn.hostname, option host-name);
     set ClientIp = binary-to-ascii(10, 8, ".",leased-address);
-    set ClientMac = binary-to-ascii(16, 8, ":",substring(hardware, 1, 6));
-    set ClientDomain = pick-first-value(config-option domain-name, "..YYZ!");
-    execute("/usr/libexec/vyos/system/on-dhcp-event.sh", "release", ClientName, ClientIp, ClientMac, ClientDomain);
+    execute("/usr/libexec/vyos/system/on-dhcp-event.sh", "release", "", ClientIp, "", "");
 }
 on expiry {
     set ClientName = pick-first-value(host-decl-name, option fqdn.hostname, option host-name);
     set ClientIp = binary-to-ascii(10, 8, ".",leased-address);
-    set ClientMac = binary-to-ascii(16, 8, ":",substring(hardware, 1, 6));
-    set ClientDomain = pick-first-value(config-option domain-name, "..YYZ!");
-    execute("/usr/libexec/vyos/system/on-dhcp-event.sh", "release", ClientName, ClientIp, ClientMac, ClientDomain);
+    execute("/usr/libexec/vyos/system/on-dhcp-event.sh", "release", "", ClientIp, "", "");
 }
 {% endif %}
 
@@ -209,11 +205,15 @@ shared-network {{ network | replace('_','-') }} {
     on commit {
         set shared-networkname = "{{ network | replace('_','-') }}";
 {%     if hostfile_update is defined %}
-        set ClientName = pick-first-value(host-decl-name, option fqdn.hostname, option host-name);
         set ClientIp = binary-to-ascii(10, 8, ".", leased-address);
         set ClientMac = binary-to-ascii(16, 8, ":", substring(hardware, 1, 6));
-        set ClientDomain = pick-first-value(config-option domain-name, "..YYZ!");
-        execute("/usr/libexec/vyos/system/on-dhcp-event.sh", "commit", ClientName, ClientIp, ClientMac, ClientDomain);
+        set ClientName = pick-first-value(host-decl-name, option fqdn.hostname, option host-name, "empty_hostname");
+        if not (ClientName = "empty_hostname") {
+            set ClientDomain = pick-first-value(config-option domain-name, "..YYZ!");
+            execute("/usr/libexec/vyos/system/on-dhcp-event.sh", "commit", ClientName, ClientIp, ClientMac, ClientDomain);
+        } else {
+            log(concat("Hostname is not defined for client with IP: ", ClientIP, " MAC: ", ClientMac));
+        }
 {%     endif %}
     }
 }
diff --git a/src/system/on-dhcp-event.sh b/src/system/on-dhcp-event.sh
index a062dc810..49e53d7e1 100755
--- a/src/system/on-dhcp-event.sh
+++ b/src/system/on-dhcp-event.sh
@@ -21,21 +21,20 @@ client_mac=$4
 domain=$5
 hostsd_client="/usr/bin/vyos-hostsd-client"
 
-if [ -z "$client_name" ]; then
-    logger -s -t on-dhcp-event "Client name was empty, using MAC \"$client_mac\" instead"
-    client_name=$(echo "client-"$client_mac | tr : -)
-fi
-
-if [ "$domain" == "..YYZ!" ]; then
-    client_fqdn_name=$client_name
-    client_search_expr=$client_name
-else
-    client_fqdn_name=$client_name.$domain
-    client_search_expr="$client_name\\.$domain"
-fi
-
 case "$action" in
   commit) # add mapping for new lease
+    if [ -z "$client_name" ]; then
+        logger -s -t on-dhcp-event "Client name was empty, using MAC \"$client_mac\" instead"
+        client_name=$(echo "client-"$client_mac | tr : -)
+    fi
+
+    if [ "$domain" == "..YYZ!" ]; then
+        client_fqdn_name=$client_name
+        client_search_expr=$client_name
+    else
+        client_fqdn_name=$client_name.$domain
+        client_search_expr="$client_name\\.$domain"
+    fi
     $hostsd_client --add-hosts "$client_fqdn_name,$client_ip" --tag "dhcp-server-$client_ip" --apply
     exit 0
     ;;