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.

(cherry picked from commit bed1cd01904ef89b5d31bd47de0f230214900f16)

4 files changed, 40 insertions, 6 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.
diff --git a/interface-definitions/include/constraint/dhcp-client-string-option.xml.i b/interface-definitions/include/constraint/dhcp-client-string-option.xml.i
new file mode 100644
index 000000000..76e0e5466
--- /dev/null
+++ b/interface-definitions/include/constraint/dhcp-client-string-option.xml.i
@@ -0,0 +1,4 @@
+<!-- include start from include/constraint/dhcp-client-string-option.xml.i -->
+<regex>[-_a-zA-Z0-9\s]+</regex>
+<regex>([a-fA-F0-9][a-fA-F0-9]:){2,}[a-fA-F0-9][a-fA-F0-9]</regex>
+<!-- include end -->
diff --git a/interface-definitions/include/interface/dhcp-options.xml.i b/interface-definitions/include/interface/dhcp-options.xml.i
index 8027769ff..fff83fd5c 100644
--- a/interface-definitions/include/interface/dhcp-options.xml.i
+++ b/interface-definitions/include/interface/dhcp-options.xml.i
@@ -7,6 +7,13 @@
     <leafNode name="client-id">
       <properties>
         <help>Identifier used by client to identify itself to the DHCP server</help>
+        <valueHelp>
+          <format>txt</format>
+          <description>DHCP option string</description>
+        </valueHelp>
+        <constraint>
+          #include <include/constraint/dhcp-client-string-option.xml.i>
+        </constraint>
       </properties>
     </leafNode>
     <leafNode name="host-name">
@@ -27,6 +34,13 @@
     <leafNode name="vendor-class-id">
       <properties>
         <help>Identify the vendor client type to the DHCP server</help>
+        <valueHelp>
+          <format>txt</format>
+          <description>DHCP option string</description>
+        </valueHelp>
+        <constraint>
+          #include <include/constraint/dhcp-client-string-option.xml.i>
+        </constraint>
       </properties>
     </leafNode>
     #include <include/interface/no-default-route.xml.i>
diff --git a/smoketest/scripts/cli/base_interfaces_test.py b/smoketest/scripts/cli/base_interfaces_test.py
index 277f14067..81240f78b 100644
--- a/smoketest/scripts/cli/base_interfaces_test.py
+++ b/smoketest/scripts/cli/base_interfaces_test.py
@@ -158,14 +158,20 @@ class BasicInterfaceTest:
             if not self._test_dhcp or not self._test_vrf:
                 self.skipTest('not supported')
 
+            client_id = 'VyOS-router'
             distance = '100'
+            hostname = 'vyos'
+            vendor_class_id = 'vyos-vendor'
 
             for interface in self._interfaces:
                 for option in self._options.get(interface, []):
                     self.cli_set(self._base_path + [interface] + option.split())
 
                 self.cli_set(self._base_path + [interface, 'address', 'dhcp'])
+                self.cli_set(self._base_path + [interface, 'dhcp-options', 'client-id', client_id])
                 self.cli_set(self._base_path + [interface, 'dhcp-options', 'default-route-distance', distance])
+                self.cli_set(self._base_path + [interface, 'dhcp-options', 'host-name', hostname])
+                self.cli_set(self._base_path + [interface, 'dhcp-options', 'vendor-class-id', vendor_class_id])
 
             self.cli_commit()
 
@@ -175,8 +181,11 @@ class BasicInterfaceTest:
                 self.assertTrue(dhclient_pid)
 
                 dhclient_config = read_file(f'{dhclient_base_dir}/dhclient_{interface}.conf')
-                self.assertIn('request subnet-mask, broadcast-address, routers, domain-name-servers', dhclient_config)
-                self.assertIn('require subnet-mask;', dhclient_config)
+                self.assertIn(f'request subnet-mask, broadcast-address, routers, domain-name-servers', dhclient_config)
+                self.assertIn(f'require subnet-mask;', dhclient_config)
+                self.assertIn(f'send host-name "{hostname}";', dhclient_config)
+                self.assertIn(f'send dhcp-client-identifier "{client_id}";', dhclient_config)
+                self.assertIn(f'send vendor-class-identifier "{vendor_class_id}";', dhclient_config)
 
                 # and the commandline has the appropriate options
                 cmdline = read_file(f'/proc/{dhclient_pid}/cmdline')