dhcp-client: T5760: add constraints for dhclient string options

The string data type specifies either an NVT ASCII string enclosed in double
quotes, or a series of octets specified in hexadecimal, separated by colons.

For example:

set interfaces ethernet eth0 dhcp-options client-id CLIENT-FOO
or
set interfaces ethernet eth0 dhcp-options client-id 43:4c:49:45:54:2d:46:4f:4f

As of now there was no input validation performed.

1 files changed, 11 insertions, 4 deletions

diff --git a/data/templates/dhcp-client/ipv4.j2 b/data/templates/dhcp-client/ipv4.j2
index cc5ddf09c..4a5d5e54d 100644
--- a/data/templates/dhcp-client/ipv4.j2
+++ b/data/templates/dhcp-client/ipv4.j2
@@ -9,14 +9,21 @@ interface "{{ ifname }}" {
     send host-name "{{ dhcp_options.host_name }}";
 {% if dhcp_options.client_id is vyos_defined %}
 {%     set client_id = dhcp_options.client_id %}
-{#   Use HEX representation of client-id as it is send in MAC-address style using hex characters. If not HEX, use double quotes ASCII format #}
-{%     if not dhcp_options.client_id.split(':') | length >= 5 %}
-{%         set client_id = '"' + dhcp_options.client_id + '"' %}
+{#   Use HEX representation of client-id as it is send in MAC-address style using hex characters. #}
+{#   If not HEX, use double quotes ASCII format #}
+{%     if not client_id.split(':') | length >= 3 %}
+{%         set client_id = '"' ~ dhcp_options.client_id ~ '"' %}
 {%     endif %}
     send dhcp-client-identifier {{ client_id }};
 {% endif %}
 {% if dhcp_options.vendor_class_id is vyos_defined %}
-    send vendor-class-identifier "{{ dhcp_options.vendor_class_id }}";
+{%     set vendor_class_id = dhcp_options.vendor_class_id %}
+{#   Use HEX representation of client-id as it is send in MAC-address style using hex characters. #}
+{#   If not HEX, use double quotes ASCII format #}
+{%     if not vendor_class_id.split(':') | length >= 3 %}
+{%         set vendor_class_id = '"' ~ dhcp_options.vendor_class_id ~ '"' %}
+{%     endif %}
+    send vendor-class-identifier {{ vendor_class_id }};
 {% endif %}
     # The request statement causes the client to request that any server responding to the
     # client send the client its values for the specified options.