dhcp-server: T3936: Added support for DHCP Option 82

data/templates/dhcp-server/kea-dhcp4.conf.j2

@@ -28,6 +28,9 @@
             "persist": true,
             "name": "{{ lease_file }}"
         },
+{% if client_class is vyos_defined %}
+        "client-classes": {{ client_class | kea_client_class_json }},
+{% endif %}
         "option-def": [
             {
                 "name": "wpad-url",

interface-definitions/include/dhcp/dhcp-server-common-config.xml.i

@@ -1,4 +1,49 @@
 <!-- include start from dhcp/dhcp-server-common-config.xml.i -->
+<tagNode name="client-class">
+  <properties>
+    <help>Client class name</help>
+    <constraint>
+      #include <include/constraint/alpha-numeric-hyphen-underscore-dot.xml.i>
+    </constraint>
+    <constraintErrorMessage>Client class name may only contain letters, numbers, dots, underscores, and hyphens</constraintErrorMessage>
+  </properties>
+  <children>
+    #include <include/generic-disable-node.xml.i>
+    <node name="relay-agent-information">
+      <properties>
+        <help>Match DHCP Option 82 (relay agent information)</help>
+      </properties>
+      <children>
+        <leafNode name="circuit-id">
+          <properties>
+            <help>Filters on the contents of the circuit-id sub option</help>
+            <valueHelp>
+              <format>hex</format>
+              <description>Values that start with 0x are interpreted as raw hex. This must only be hexadecimal characters e.g. 0x1234567890ABCDEF</description>
+            </valueHelp>
+            <valueHelp>
+              <format>txt</format>
+              <description>Any other text string is interpreted as ASCII text</description>
+            </valueHelp>
+          </properties>
+        </leafNode>
+        <leafNode name="remote-id">
+          <properties>
+            <help>Filters on the contents of the remote-id sub option.</help>
+            <valueHelp>
+              <format>hex</format>
+              <description>Values that start with 0x are interpreted as raw hex. This must only be hexadecimal characters e.g. 0x1234567890ABCDEF</description>
+            </valueHelp>
+            <valueHelp>
+              <format>txt</format>
+              <description>Any other text string is interpreted as ASCII text</description>
+            </valueHelp>
+          </properties>
+        </leafNode>
+      </children>
+    </node>
+  </children>
+</tagNode>
 #include <include/generic-disable-node.xml.i>
 <node name="dynamic-dns-update">
   <properties>
@@ -229,6 +274,14 @@
         #include <include/dhcp/ping-check.xml.i>
         #include <include/generic-description.xml.i>
         #include <include/generic-disable-node.xml.i>
+        <leafNode name="client-class">
+          <properties>
+            <help>DHCP client class</help>
+              <completionHelp>
+                <path>service dhcp-server client-class</path>
+              </completionHelp>
+          </properties>
+        </leafNode>
         <node name="dynamic-dns-update">
           <properties>
             <help>Dynamically update Domain Name System (RFC4702)</help>
@@ -280,6 +333,14 @@
           </properties>
           <children>
             #include <include/dhcp/option-v4.xml.i>
+            <leafNode name="client-class">
+              <properties>
+                <help>DHCP client class</help>
+                <completionHelp>
+                  <path>service dhcp-server client-class</path>
+                </completionHelp>
+              </properties>
+            </leafNode>
             <leafNode name="start">
               <properties>
                 <help>First IP address for DHCP lease range</help>

python/vyos/kea.py

@@ -169,6 +169,9 @@ def kea_parse_subnet(subnet, config):
     if 'ping_check' in config:
         out['user-context']['enable-ping-check'] = True
 
+    if 'client_class' in config:
+        out['client-class'] = config['client_class']
+
     if 'range' in config:
         pools = []
         for num, range_config in config['range'].items():
@@ -184,6 +187,9 @@ def kea_parse_subnet(subnet, config):
                 if 'bootfile_server' in range_config['option']:
                     pool['next-server'] = range_config['option']['bootfile_server']
 
+            if 'client_class' in range_config:
+                pool['client-class'] = range_config['client_class']
+
             pools.append(pool)
         out['pools'] = pools
 
@@ -667,3 +673,22 @@ def kea_get_server_leases(config, inet, vrf_name, pools=[], state=[], origin=Non
                     data.pop(idx)
 
     return data
+
+def _build_relay_hex_condition(sub_option_index, value):
+    if value.startswith("0x"):
+        return f"relay4[{sub_option_index}].hex == {value}"
+    else:
+        return f"relay4[{sub_option_index}].hex == 0x{value.encode().hex().lower()}"
+
+def kea_build_client_class_test(config):
+    conditions = []
+
+    if "relay_agent_information" in config:
+        if "circuit_id" in config["relay_agent_information"]:
+            conditions.append(_build_relay_hex_condition(1, config["relay_agent_information"]["circuit_id"]))
+        if "remote_id" in config["relay_agent_information"]:
+            conditions.append(_build_relay_hex_condition(2, config["relay_agent_information"]["remote_id"]))
+
+    test = " and ".join(conditions)
+
+    return test

python/vyos/template.py

@@ -910,6 +910,25 @@ def kea_high_availability_json(config):
 
     return dumps(data)
 
+@register_filter('kea_client_class_json')
+def kea_client_class_json(client_classes):
+    from vyos.kea import kea_build_client_class_test
+    from json import dumps
+    out = []
+
+    for name, config in client_classes.items():
+        if 'disable' in config:
+            continue
+
+        client_class = {
+            'name': name,
+            'test': kea_build_client_class_test(config)
+        }
+
+        out.append(client_class)
+
+    return dumps(out, indent=4)
+
 @register_filter('kea_dynamic_dns_update_main_json')
 def kea_dynamic_dns_update_main_json(config):
     from vyos.kea import kea_parse_ddns_settings

smoketest/scripts/cli/test_service_dhcp-server.py

@@ -112,27 +112,7 @@ def test_dhcp_single_pool_range(self):
         range_1_start = inc_ip(subnet, 40)
         range_1_stop = inc_ip(subnet, 50)
 
-        self.cli_set(base_path + ['listen-interface', interface])
-
-        self.cli_set(base_path + ['shared-network-name', shared_net_name, 'ping-check'])
-
-        pool = base_path + ['shared-network-name', shared_net_name, 'subnet', subnet]
-        self.cli_set(pool + ['subnet-id', '1'])
-        self.cli_set(pool + ['ignore-client-id'])
-        self.cli_set(pool + ['ping-check'])
-        # we use the first subnet IP address as default gateway
-        self.cli_set(pool + ['option', 'default-router', router])
-        self.cli_set(pool + ['option', 'name-server', dns_1])
-        self.cli_set(pool + ['option', 'name-server', dns_2])
-        self.cli_set(pool + ['option', 'domain-name', domain_name])
-
-        # check validate() - No DHCP address range or active static-mapping set
-        with self.assertRaises(ConfigSessionError):
-            self.cli_commit()
-        self.cli_set(pool + ['range', '0', 'start', range_0_start])
-        self.cli_set(pool + ['range', '0', 'stop', range_0_stop])
-        self.cli_set(pool + ['range', '1', 'start', range_1_start])
-        self.cli_set(pool + ['range', '1', 'stop', range_1_stop])
+        self.setup_single_pool_range(range_0_start, range_0_stop, range_1_start, range_1_stop, shared_net_name)
 
         # commit changes
         self.cli_commit()
@@ -209,6 +189,112 @@ def test_dhcp_single_pool_range(self):
         # Check for running process
         self.verify_service_running()
 
+    def setup_single_pool_range(self, range_0_start, range_0_stop, range_1_start, range_1_stop, shared_net_name):
+        self.cli_set(base_path + ['listen-interface', interface])
+        self.cli_set(base_path + ['shared-network-name', shared_net_name, 'ping-check'])
+
+        pool = base_path + ['shared-network-name', shared_net_name, 'subnet', subnet]
+
+        self.cli_set(pool + ['subnet-id', '1'])
+        self.cli_set(pool + ['ignore-client-id'])
+        self.cli_set(pool + ['ping-check'])
+        # we use the first subnet IP address as default gateway
+        self.cli_set(pool + ['option', 'default-router', router])
+        self.cli_set(pool + ['option', 'name-server', dns_1])
+        self.cli_set(pool + ['option', 'name-server', dns_2])
+        self.cli_set(pool + ['option', 'domain-name', domain_name])
+
+        # check validate() - No DHCP address range or active static-mapping set
+        with self.assertRaises(ConfigSessionError):
+            self.cli_commit()
+
+        self.cli_set(pool + ['range', '0', 'start', range_0_start])
+        self.cli_set(pool + ['range', '0', 'stop', range_0_stop])
+        self.cli_set(pool + ['range', '1', 'start', range_1_start])
+        self.cli_set(pool + ['range', '1', 'stop', range_1_stop])
+
+    def test_dhcp_client_class(self):
+        shared_net_name = 'SMOKE-1'
+
+        range_0_start = inc_ip(subnet, 10)
+        range_0_stop = inc_ip(subnet, 20)
+        range_1_start = inc_ip(subnet, 40)
+        range_1_stop = inc_ip(subnet, 50)
+
+        self.setup_single_pool_range(range_0_start, range_0_stop, range_1_start, range_1_stop, shared_net_name)
+
+        self.cli_set(base_path + ['shared-network-name', shared_net_name, 'subnet', subnet, 'client-class', 'test'])
+
+        # check validate() - Client class referenced that doesn't exist yet
+        with self.assertRaises(ConfigSessionError):
+            self.cli_commit()
+
+        self.cli_delete(base_path + ['shared-network-name', shared_net_name, 'subnet', subnet, 'client-class', 'test'])
+
+        self.cli_set(base_path + ['shared-network-name', shared_net_name, 'subnet', subnet, 'range', '0', 'client-class', 'test'])
+
+        # check validate() - Client class referenced that doesn't exist yet
+        with self.assertRaises(ConfigSessionError):
+            self.cli_commit()
+
+        self.cli_set(base_path + ['shared-network-name', shared_net_name, 'subnet', subnet, 'client-class', 'test'])
+
+        client_class = base_path + ['client-class', 'test']
+
+        # Test that invalid hex is rejected
+        self.cli_set(client_class + ['relay-agent-information', 'circuit-id', '0xHELLOWORLD'])
+
+        with self.assertRaises(ConfigSessionError):
+            self.cli_commit()
+
+        self.cli_delete(client_class + ['relay-agent-information', 'circuit-id'])
+        self.cli_set(client_class + ['relay-agent-information', 'remote-id', '0xHELLOWORLD'])
+
+        with self.assertRaises(ConfigSessionError):
+            self.cli_commit()
+
+        self.cli_delete(client_class + ['relay-agent-information', 'remote-id'])
+
+        # Test string literals
+        self.cli_set(client_class + ['relay-agent-information', 'circuit-id', 'foo'])
+        self.cli_set(client_class + ['relay-agent-information', 'remote-id', 'bar'])
+
+        self.cli_commit()
+
+        self.check_client_class_in_config()
+
+        self.cli_delete(client_class + ['relay-agent-information', 'circuit-id'])
+        self.cli_delete(client_class + ['relay-agent-information', 'remote-id'])
+
+        # Test hex strings
+        self.cli_set(client_class + ['relay-agent-information', 'circuit-id', '0x666f6f'])
+        self.cli_set(client_class + ['relay-agent-information', 'remote-id', '0x626172'])
+
+        self.cli_commit()
+
+        self.check_client_class_in_config()
+
+    def check_client_class_in_config(self):
+        config = read_file(KEA4_CONF)
+        obj = loads(config)
+        self.verify_config_value(
+            obj, ['Dhcp4', 'client-classes', 0], 'name', 'test'
+        )
+        self.verify_config_value(
+            obj, ['Dhcp4', 'client-classes', 0], 'test',
+            'relay4[1].hex == 0x666f6f and relay4[2].hex == 0x626172'
+        )
+        self.verify_config_value(
+            obj, ['Dhcp4', 'shared-networks', 0, 'subnet4', 0], 'client-class',
+            'test'
+        )
+        self.verify_config_value(
+            obj, ['Dhcp4', 'shared-networks', 0, 'subnet4', 0, 'pools', 0],
+            'client-class', 'test'
+        )
+        # Check for running process
+        self.verify_service_running()
+
     def test_dhcp_single_pool_options(self):
         shared_net_name = 'SMOKE-0815'
 

src/conf_mode/service_dhcp-server.py

@@ -15,6 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
+import re
 
 from sys import exit
 from sys import argv
@@ -286,6 +287,15 @@ def verify(dhcp):
                             f'DHCP static-route "{route}" requires router to be defined!'
                         )
 
+            # If a client class has been specified then it must exist
+            if 'client_class' in subnet_config:
+                client_class = subnet_config['client_class']
+                if 'client_class' not in dhcp:
+                    raise ConfigError(f'Client class "{client_class}" set in subnet "{subnet}" but does not exist')
+
+                if client_class not in dhcp['client_class'].keys():
+                    raise ConfigError(f'Client class "{client_class}" set in subnet "{subnet}" but does not exist')
+
             # Check if DHCP address range is inside configured subnet declaration
             if 'range' in subnet_config:
                 networks = []
@@ -295,6 +305,15 @@ def verify(dhcp):
                             f'DHCP range "{range}" start and stop address must be defined!'
                         )
 
+                    # If a client class has been specified then it must exist
+                    if 'client_class' in range_config:
+                        client_class = range_config['client_class']
+                        if 'client_class' not in dhcp:
+                            raise ConfigError(f'Client class "{client_class}" set in range "{range}" but does not exist')
+
+                        if client_class not in dhcp['client_class'].keys():
+                            raise ConfigError(f'Client class "{client_class}" set in range "{range}" but does not exist')
+
                     # Start/Stop address must be inside network
                     for key in ['start', 'stop']:
                         if ip_address(range_config[key]) not in ip_network(subnet):
@@ -503,6 +522,26 @@ def verify(dhcp):
         if 'reverse_domain' in ddns:
             verify_ddns_domain_servers('Reverse', ddns['reverse_domain'])
 
+    if 'client_class' in dhcp:
+        # Check client class values are valid
+        for class_name, class_config in dhcp['client_class'].items():
+            if 'relay_agent_information' in class_config:
+                relay_agent_information_config = class_config['relay_agent_information']
+                # Compile a regex that will scan for valid inputs. Input can be
+                # either hex in the form 0x0123456789ABCDEF or a string that
+                # does *not* start with 0x. i.e. 0xHELLOWORLD is bad
+                pattern = re.compile(r'^(?:0x[0-9A-Fa-f]+|(?!0x).+)$')
+
+                if 'circuit_id' in relay_agent_information_config:
+                    circuit_id = relay_agent_information_config['circuit_id']
+                    if not pattern.match(circuit_id):
+                        raise ConfigError(f'Invalid circuit-id "{circuit_id}" must be either text literal or hex string starting with 0x')
+
+                if 'remote_id' in relay_agent_information_config:
+                    remote_id = relay_agent_information_config['remote_id']
+                    if not pattern.match(remote_id):
+                        raise ConfigError(f'Invalid remote-id "{remote_id}" must be either text literal or hex string starting with 0x')
+
     return None