T560: dns-forwarding: replace dnsmasq with pdns-recursor

2 files changed, 58 insertions, 35 deletions

diff --git a/interface-definitions/dns-forwarding.xml b/interface-definitions/dns-forwarding.xml
index f1edec414..d56911c60 100644
--- a/interface-definitions/dns-forwarding.xml
+++ b/interface-definitions/dns-forwarding.xml
@@ -32,7 +32,6 @@
               <tagNode name="domain">
                 <properties>
                   <help>DNS domain to forward to a local server</help>
-                  <type>txt</type>
                 </properties>
                 <children>
                   <leafNode name="server">
@@ -77,12 +76,8 @@
                     <format>ipv6</format>
                     <description>Domain Name Server (DNS) IPv6 address</description>
                   </valueHelp>
-                <multi/>
-                </properties>
-              </leafNode>
-              <leafNode name="query-all-servers">
-                <properties>
-                  <help>Query all DNS servers, respond and cache fastest result</help>
+                  <multi/>
+                  <type>ipv4,ipv6</type>
                 </properties>
               </leafNode>
               <leafNode name="system">
diff --git a/src/conf-mode/vyos-config-dns-forwarding.py b/src/conf-mode/vyos-config-dns-forwarding.py
index 742e111cb..7a8aed75d 100755
--- a/src/conf-mode/vyos-config-dns-forwarding.py
+++ b/src/conf-mode/vyos-config-dns-forwarding.py
@@ -19,11 +19,12 @@
 import sys
 import os
 import time
+import netifaces
 
 from vyos.config import Config
 from vyos.util import ConfigError
 
-config_file = r'/etc/dnsmasq.d/vyos.conf'
+config_file = r'/etc/powerdns/recursor.conf'
 
 # borrowed from: https://github.com/donjajo/py-world/blob/master/resolvconfReader.py, THX!
 def get_resolvers(file):
@@ -65,7 +66,7 @@ def get_config():
     if conf.exists('domain'):
         dns.setdefault('domain', [])
         for node in conf.list_nodes('domain'):
-            server = conf.return_value("domain {0} server".format(node))
+            server = conf.return_values("domain {0} server".format(node))
             domain = {
                 "name": node,
                 "server": server
@@ -85,75 +86,102 @@ def get_config():
         nameservers = conf.return_values('name-server')
         dns.setdefault('name-server', nameservers)
 
-    if conf.exists('query-all-servers'):
-        dns.setdefault('query-all-servers', True)
-
     if conf.exists('system'):
         conf.set_level('system')
         nameservers = []
         nameservers = conf.return_values('name-server')
         if len(nameservers) == 0:
             print("DNS forwarding warning: No name-servers set under 'system name-server'\n")
-        dns.setdefault('system-name-server', True)
+        else:
+            dns.setdefault('system-name-server', nameservers)
 
     return dns
 
 def verify(dns):
     if len(dns) > 0:
         if 'listen-on' not in dns.keys():
-            raise ConfigError("Error: DNS forwarding requires a configured listen interface!")
+            raise ConfigError('Error: DNS forwarding requires a configured listen interface!')
+
+        for interface in dns['listen-on']:
+            try:
+                netifaces.ifaddresses(interface)[netifaces.AF_INET]
+            except KeyError as e:
+                raise ConfigError('Error: Interface {0} has no IP address assigned'.format(interface))
+
+        if 'domain' in dns.keys():
+            for domain in dns['domain']:
+                if len(domain['server']) == 0:
+                    raise ConfigError('Error: No server configured for domain {0}'.format(domain['name']))
 
     return None
 
 def generate(dns):
     config_header = '### Autogenerated by vyos-config-dns-forwarding.py on {tm} ###\n'.format(tm=time.strftime("%a, %d %b %Y %H:%M:%S", time.localtime()))
 
+    fwds = []
+    fwds_src = []
+
     # write new configuration file
     f = open(config_file, 'w')
     f.write(config_header)
-    f.write("log-facility=/var/log/dnsmasq.log\n")
-    f.write("no-poll\n")
-    f.write("edns-packet-max=4096\n")
-    f.write("bind-interfaces\n")
+    f.write('daemon=yes\n')
+    f.write('threads=1\n')
+    f.write('allow-from=0.0.0.0/0\n')
+    f.write('log-common-errors=yes\n')
 
     if 'listen-on' in dns.keys():
+        listen4 = []
+        listen6 = []
         for interface in dns['listen-on']:
-            f.write("interface={0}\n".format(interface))
+            addrs = netifaces.ifaddresses(interface)
+            for ip4 in addrs[netifaces.AF_INET]:
+                listen4.append(ip4['addr'])
+
+            for ip6 in addrs[netifaces.AF_INET6]:
+                listen6.append(ip6['addr'])
+
+        # build local-address string, example:
+        # local-address=172.16.37.240, 127.0.0.1, 172.16.254.35, 172.16.77.1, 2001:DB8::1:25, ::1
+        f.write('local-address=' + ', '.join(listen4) + ', ' + ', '.join(listen6) + '\n')
+
+    if 'cache-size' in dns.keys():
+        f.write("max-cache-entries={0}\n".format(dns['cache-size']))
 
     if 'dhcp' in dns.keys():
         for dhcp in dns['dhcp']:
-            for resolver in dhcp['resolvers']:
-                f.write("server={0}\t# dhcp {1}\n".format(resolver, dhcp['interface']))
+            fwds_src.append('DHCP: {0} ({1})'.format(dhcp['interface'], ', '.join(str(ns) for ns in dhcp['resolvers'])))
+            fwds.append(', '.join(str(ns) for ns in dhcp['resolvers']))
 
     if 'domain' in dns.keys():
+        zones = []
         for domain in dns['domain']:
-            f.write("server=/{0}/{1}\t# domain-override\n".format(domain['name'], domain['server']))
-
-    if 'cache-size' in dns.keys():
-        f.write("cache-size={0}\n".format(dns['cache-size']))
+            zones.append('{0}={1}'.format(domain['name'], ';'.join(str(ns) for ns in domain['server'])))
+        f.write('forward-zones=' + ', '.join(zones) + '\n')
 
     if 'ignore-hosts-file' in dns.keys():
-        f.write("no-hosts\n")
+        f.write("export-etc-hosts=no\n")
 
     if 'name-server' in dns.keys():
-        for nameserver in dns['name-server']:
-            f.write("server={0}\t# statically configured\n".format(nameserver))
-
-    if 'query-all-servers' in dns.keys():
-        f.write("all-servers\n")
+        fwds_src.append('statically configured: {0}'.format(', '.join(str(ns) for ns in dns['name-server'])))
+        fwds.append(', '.join(str(ns) for ns in dns['name-server']))
 
     if 'system-name-server' in dns.keys():
-        # Read the IP addresses of the upstream nameservers from /etc/resolv.conf
-        f.write("resolv-file=/etc/resolv.conf\n")
+        fwds_src.append('system: {0}'.format(', '.join(str(ns) for ns in dns['system-name-server'])))
+        fwds.append(', '.join(str(ns) for ns in dns['system-name-server']))
+
+    if len(fwds) > 0:
+        f.write('\n')
+        f.write('# ' + '\n# '.join(fwds_src) + '\n')
+        f.write('forward-zones-recurse=.=' + '; '.join(fwds) + '\n')
 
     f.close()
     return None
 
 def apply(dns):
     if len(dns) == 0:
-        cmd = "sudo systemctl stop dnsmasq"
+        cmd = "sudo systemctl stop pdns-recursor"
     else:
-        cmd = "sudo systemctl restart dnsmasq"
+        cmd = "sudo systemctl restart pdns-recursor"
 
     os.system(cmd)
     return None