From cb6f12b218e3865867ac559e83472b72e4e3e6f8 Mon Sep 17 00:00:00 2001
From: Franziska Kunsmann <hi@kunsmann.eu>
Date: Sat, 9 Sep 2023 18:40:10 +0200
Subject: [PATCH] add bundle:kea-dhcp-server

---
 bundles/kea-dhcp-server/items.py    | 42 +++++++++++++++
 bundles/kea-dhcp-server/metadata.py | 83 +++++++++++++++++++++++++++++
 2 files changed, 125 insertions(+)
 create mode 100644 bundles/kea-dhcp-server/items.py
 create mode 100644 bundles/kea-dhcp-server/metadata.py

diff --git a/bundles/kea-dhcp-server/items.py b/bundles/kea-dhcp-server/items.py
new file mode 100644
index 0000000..921bf78
--- /dev/null
+++ b/bundles/kea-dhcp-server/items.py
@@ -0,0 +1,42 @@
+kea_config = {
+    'Dhcp4': {
+        **node.metadata.get('kea-dhcp-server/config'),
+        'interfaces-config': {
+            'interfaces': sorted(node.metadata.get('kea-dhcp-server/subnets', {}).keys()),
+        },
+        'subnet4': [],
+    },
+    'Server': {
+        'loggers': [{
+            'name': 'kea-dhcp4',
+            'output_options': [{
+                # -> journal
+                'output': 'stdout',
+            }],
+            'severity': 'WARN',
+        }],
+    },
+}
+
+for iface, config in sorted(node.metadata.get('kea-dhcp-server/subnets', {}).items()):
+    kea_config['Dhcp4']['subnet4'].append({
+        'subnet': config['subnet'],
+        'pools': [{
+            'pool': f'{config["lower"]} - {config["higher"]}',
+        }],
+        'option-data': [
+            {
+                'name': k,
+                'data': v,
+            } for k, v in sorted(config.get('options', {}).items())
+        ],
+        'reservations': [
+            {
+                'ip-address': v['ip'],
+                'hw-address': v['mac'],
+                'hostname': k,
+            } for k, v in sorted(node.metadata.get(f'kea-dhcp-server/fixed_allocations/{iface}', {}).items())
+        ]
+    })
+
+# TODO deploy config
diff --git a/bundles/kea-dhcp-server/metadata.py b/bundles/kea-dhcp-server/metadata.py
new file mode 100644
index 0000000..7b69f3e
--- /dev/null
+++ b/bundles/kea-dhcp-server/metadata.py
@@ -0,0 +1,83 @@
+from ipaddress import ip_address, ip_network
+
+defaults = {
+    'apt': {
+        'packages': {
+            'kea-dhcp4-server': {},
+        },
+    },
+    'kea-dhcp-server': {
+        'config': {
+            'authoritative': True,
+            'rebind-timer': 450,
+            'renew-timer': 300,
+            'valid-lifetime': 600,
+            'expired-leases-processing': {
+                'max-reclaim-leases': 0,
+                'max-reclaim-time': 0,
+            },
+            'lease-database': {
+                'lfc-interval': 3600,
+                'name': '/var/lib/kea/kea-leases4.csv',
+                'persist': True,
+                'type': 'memfile',
+            },
+        },
+    },
+}
+
+
+@metadata_reactor.provides(
+    'kea-dhcp-server/fixed_allocations',
+)
+def get_static_allocations(metadata):
+    result = {}
+    mapping = {}
+
+    for iface, config in metadata.get('kea-dhcp-server/subnets', {}).items():
+        result[iface] = {}
+        mapping[iface] = ip_network(config['subnet'])
+
+    for rnode in repo.nodes:
+        if (
+            rnode.metadata.get('location', '') != metadata.get('location', '')
+            or rnode == node
+        ):
+            continue
+
+        for iface_name, iface_config in rnode.metadata.get('interfaces', {}).items():
+            if iface_config.get('dhcp', False) and iface_config.get('mac'):
+                for ip in iface_config.get('ips', set()):
+                    ipaddr = ip_address(ip)
+
+                    for kea_iface, kea_subnet in mapping.items():
+                        if ipaddr in kea_subnet:
+                            result[kea_iface][f'{rnode.name}_{iface_name}'] = {
+                                'ip': ip,
+                                'mac': iface_config['mac'],
+                            }
+                            break
+
+    return {
+        'kea-dhcp-server': {
+            'fixed_allocations': result,
+        }
+    }
+
+
+@metadata_reactor.provides(
+    'nftables/rules/10-kea-dhcp-server',
+)
+def nftables(metadata):
+    rules = set()
+    for iface in node.metadata.get('kea-dhcp-server/subnets', {}):
+        rules.add(f'inet filter input udp dport {{ 67, 68 }} iif {iface} accept')
+
+    return {
+        'nftables': {
+            'rules': {
+                # can't use port_rules here, because we're generating interface based rules.
+                '10-kea-dhcp-server': sorted(rules),
+            },
+        }
+    }