dhcp: T3316: Support hostname, DUID and MAC address in reservation

Reinstate support for hostname in DHCP reservation. Having `hostname` in
allows for server-side assignment of hostname. This is useful for static
lookup of hostname.

Ensure that hostname is a valid FQDN (doesn't have underscore, etc.)

Additionally, support using either of DUID or MAC address for
reservation. While MAC address is typically used for IPv4, and DUID is
typically used for IPv6, either of them can be used in IPv4 and IPv6
reservations in Kea.

2 files changed, 10 insertions, 5 deletions

diff --git a/src/conf_mode/dhcp_server.py b/src/conf_mode/dhcp_server.py
index 958e90014..abccdb6a9 100755
--- a/src/conf_mode/dhcp_server.py
+++ b/src/conf_mode/dhcp_server.py
@@ -18,7 +18,6 @@ import os
 
 from ipaddress import ip_address
 from ipaddress import ip_network
-from netaddr import IPAddress
 from netaddr import IPRange
 from sys import exit
 
@@ -141,7 +140,7 @@ def get_config(config=None):
                                 {'range' : new_range_dict})
 
     if dict_search('failover.certificate', dhcp):
-        dhcp['pki'] = conf.get_config_dict(['pki'], key_mangling=('-', '_'), get_first_key=True, no_tag_node_value_mangle=True) 
+        dhcp['pki'] = conf.get_config_dict(['pki'], key_mangling=('-', '_'), get_first_key=True, no_tag_node_value_mangle=True)
 
     return dhcp
 
@@ -226,9 +225,10 @@ def verify(dhcp):
                             raise ConfigError(f'Configured static lease address for mapping "{mapping}" is\n' \
                                               f'not within shared-network "{network}, {subnet}"!')
 
-                        if 'mac_address' not in mapping_config:
-                            raise ConfigError(f'MAC address required for static mapping "{mapping}"\n' \
-                                              f'within shared-network "{network}, {subnet}"!')
+                        if ('mac' not in mapping_config and 'duid' not in mapping_config) or \
+                            ('mac' in mapping_config and 'duid' in mapping_config):
+                            raise ConfigError(f'Either MAC address or Client identifier (DUID) is required for '
+                                              f'static mapping "{mapping}" within shared-network "{network}, {subnet}"!')
 
             # There must be one subnet connected to a listen interface.
             # This only counts if the network itself is not disabled!
diff --git a/src/conf_mode/dhcpv6_server.py b/src/conf_mode/dhcpv6_server.py
index b01f510e5..f9da3d84a 100755
--- a/src/conf_mode/dhcpv6_server.py
+++ b/src/conf_mode/dhcpv6_server.py
@@ -135,6 +135,11 @@ def verify(dhcpv6):
                         if ip_address(mapping_config['ipv6_address']) not in ip_network(subnet):
                             raise ConfigError(f'static-mapping address for mapping "{mapping}" is not in subnet "{subnet}"!')
 
+                        if ('mac' not in mapping_config and 'duid' not in mapping_config) or \
+                            ('mac' in mapping_config and 'duid' in mapping_config):
+                            raise ConfigError(f'Either MAC address or Client identifier (DUID) is required for '
+                                              f'static mapping "{mapping}" within shared-network "{network}, {subnet}"!')
+
             if 'vendor_option' in subnet_config:
                 if len(dict_search('vendor_option.cisco.tftp_server', subnet_config)) > 2:
                     raise ConfigError(f'No more then two Cisco tftp-servers should be defined for subnet "{subnet}"!')