dns/ddclient: add Netcup DNS API

Netcup is a German hosting provider who offers an API for DNS
manipulation which this plugin makes use of, see:
- Wiki: https://www.netcup-wiki.de/wiki/DNS_API
- Technical documentation: https://ccp.netcup.net/run/webservice/servers/endpoint.php

dns/ddclient/src/opnsense/mvc/app/controllers/OPNsense/DynDNS/forms/dialogAccount.xml

@@ -51,6 +51,13 @@
         <type>password</type>
         <help>Password associated with this account</help>
     </field>
+    <field>
+        <id>account.netcupAPIKey</id>
+        <label>Netcup API Key</label>
+        <type>password</type>
+        <style>optional_setting service_netcup</style>
+        <help>Netcup API key. Enter Netcup customer number in username field and Netcup API password in password field.</help>
+    </field>
     <field>
         <id>account.wildcard</id>
         <label>Wildcard</label>
@@ -77,7 +84,7 @@
         <id>account.ttl</id>
         <label>TTL</label>
         <type>text</type>
-        <style>optional_setting service_aws</style>
+        <style>optional_setting service_aws service_netcup</style>
         <help>Time to Live for the DNS entry</help>
     </field>
     <field>

dns/ddclient/src/opnsense/scripts/ddclient/lib/account/netcup.py

@@ -0,0 +1,153 @@
+"""
+    Copyright (c) 2023 Ingo Lafrenz <opnsense@der-ingo.de>
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+
+    2. Redistributions in binary form must reproduce the above copyright
+     notice, this list of conditions and the following disclaimer in the
+     documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+    INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+    AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+    AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+    OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+    POSSIBILITY OF SUCH DAMAGE.
+    ----------------------------------------------------------------------------------------------------
+    Netcup DNS provider, see https://ccp.netcup.net/run/webservice/servers/endpoint.php
+
+"""
+import syslog
+import requests
+from . import BaseAccount
+
+class Netcup(BaseAccount):
+    _services = ['netcup']
+    _netcupAPIURL = 'https://ccp.netcup.net/run/webservice/servers/endpoint.php?JSON'
+
+    def __init__(self, account: dict):
+        super().__init__(account)
+        self.netcupCustomerNr = self.settings.get('username')
+        self.netcupAPIPassword = self.settings.get('password')
+        self.netcupAPIKey = self.settings.get('netcupAPIKey')
+        hostnames = self.settings.get('hostnames').split(',')
+        if (len(hostnames) > 1):
+            syslog.syslog(syslog.LOG_WARNING, "Multiple hostnames detected, ignoring all except first. Consider using CNAMEs or create separate DynDNS instances for each hostname.")
+        self.hostname, self.domain = hostnames[0].split('.', 1)
+        self.ttl = self.settings.get('ttl')
+        if self.ttl < 300:
+            syslog.syslog(syslog.LOG_WARNING, "TTL was auto corrected to 300s since Netcup doesn't allow smaller values.")
+            self.ttl = 300
+
+    @staticmethod
+    def known_services():
+        return Netcup._services
+
+    @staticmethod
+    def match(account):
+        return account.get('service') in Netcup._services
+
+    def execute(self):
+        super().execute()
+        netcupAPISessionID = self._login()
+        dnsZoneInfo = self._infoDnsZone(netcupAPISessionID)
+        ttl = int(dnsZoneInfo['ttl'])
+        if (self.ttl != ttl):
+            dnsZoneInfo['ttl'] = '300'
+            self._updateDNSZone(dnsZoneInfo, netcupAPISessionID)
+        dnsRecordsInfo = self._infoDnsRecords(netcupAPISessionID)
+        recordType = 'AAAA' if ':' in self.current_address else 'A'
+        self._updateIpAddress(recordType, dnsRecordsInfo, netcupAPISessionID)
+        self._logout(netcupAPISessionID)
+        self.update_state(address = self.current_address)
+        return True
+
+    def _login(self):
+        requestPayload = {
+                'action': 'login',
+                'param': {
+                    'customernumber': self.netcupCustomerNr,
+                    'apikey': self.netcupAPIKey,
+                    'apipassword': self.netcupAPIPassword
+                }
+        }
+        return Netcup._sendRequest(requestPayload)['responsedata']['apisessionid']
+
+    def _infoDnsZone(self, netcupAPISessionID):
+        return Netcup._sendRequest(self._createRequestPayload('infoDnsZone', netcupAPISessionID))['responsedata']
+
+    def _updateDNSZone(self, dnsZone, netcupAPISessionID):
+        return Netcup._sendRequest(self._createRequestPayload('updateDnsZone', netcupAPISessionID, {'dnszone': dnsZone}))['responsedata']
+
+    def _infoDnsRecords(self, netcupAPISessionID):
+        return Netcup._sendRequest(self._createRequestPayload('infoDnsRecords', netcupAPISessionID))['responsedata']
+
+    def _updateDnsRecords(self, hostRecord, netcupAPISessionID):
+        return Netcup._sendRequest(self._createRequestPayload('updateDnsRecords', netcupAPISessionID, {'dnsrecordset': {'dnsrecords': [hostRecord]}}))['responsedata']
+
+    def _logout(self, netcupAPISessionID):
+        requestPayload = {
+                'action': 'logout',
+                'param': {
+                    'customernumber': self.netcupCustomerNr,
+                    'apikey': self.netcupAPIKey,
+                    'apisessionid': netcupAPISessionID
+                }
+        }
+        return Netcup._sendRequest(requestPayload)['responsedata']
+
+    def _updateIpAddress(self, recordType, dnsRecordsInfo, netcupAPISessionID):
+        matchingRecords = [r for r in dnsRecordsInfo['dnsrecords'] if r['type'] == recordType and r['hostname'] == self.hostname]
+        if len(matchingRecords) > 1:
+            raise Exception(f'Too many {recordType} records for hostname {self.hostname} in DNS zone {self.domain}.')
+        hostRecord = {
+            'id': matchingRecords[0]['id'],
+            'hostname': matchingRecords[0]['hostname'],
+            'type': matchingRecords[0]['type'],
+            'priority': matchingRecords[0]['priority'],
+            'destination': matchingRecords[0]['destination'],
+            'deleterecord': matchingRecords[0]['deleterecord'],
+            'state': matchingRecords[0]['state'],
+        } if matchingRecords else {
+            'hostname': self.hostname,
+            'type': recordType,
+            'destination': None
+        }
+        currentNetcupIPAddress = hostRecord['destination']
+        if self.current_address != currentNetcupIPAddress:
+            syslog.syslog(syslog.LOG_NOTICE, f'IP address change detected. Old IP: {currentNetcupIPAddress}, new IP: {self.current_address}')
+            hostRecord['destination'] = self.current_address
+            self._updateDnsRecords(hostRecord, netcupAPISessionID)
+            syslog.syslog(syslog.LOG_NOTICE, f'Successfully updated {recordType} record for {self.hostname}.{self.domain} to {self.current_address}')
+        else:
+            syslog.syslog(syslog.LOG_NOTICE, 'IP address has not changed. Nothing to do.')
+
+    def _createRequestPayload(self, action, netcupAPISessionID, extraParameters = {}):
+        requestPayload = {
+                'action': action,
+                'param': {
+                    'domainname': self.domain,
+                    'customernumber': self.netcupCustomerNr,
+                    'apikey': self.netcupAPIKey,
+                    'apisessionid': netcupAPISessionID,
+                }
+        }
+        requestPayload['param'].update(extraParameters)
+        return requestPayload
+
+    @staticmethod
+    def _sendRequest(requestPayload):
+        response = requests.post(Netcup._netcupAPIURL, json = requestPayload).json();
+        if response['status'] == 'success':
+            return response
+        raise Exception(f"{requestPayload['action']} failed with status {response['status']}. response: {response}")
+

dns/ddclient/src/opnsense/service/templates/OPNsense/ddclient/ddclient.json

@@ -17,6 +17,7 @@
             "resourceId": "{{ account.resourceId }}",
             "username": "{{ account.username }}",
             "password": "{{ account.password }}",
+            "netcupAPIKey": "{{ account.netcupAPIKey }}",
             "hostnames": "{{ account.hostnames }}",
             "wildcard": {{ "true" if account.wildcard == '1' else "false"}},
             "zone": "{{ account.zone }}",