On 12/18/25 5:00 AM, Michal Privoznik via Devel wrote:
From: Michal Privoznik <[email protected]>
In the <dns/> section of network configuration users can set up
forwarding of DNS requests to custom DNS servers. These are
specified using 'addr' attribute. But configuring port wasn't
possible, until now. New 'port' attribute is introduced, which
allows overriding the default DNS port for given address.
Signed-off-by: Michal Privoznik <[email protected]>
---
docs/formatnetwork.rst | 8 +++--
src/conf/network_conf.c | 36 +++++++++++++++----
src/conf/schemas/network.rng | 5 +++
.../nat-network-dns-forwarders.xml | 2 +-
.../nat-network-dns-forwarders.xml | 2 +-
5 files changed, 42 insertions(+), 11 deletions(-)
diff --git a/docs/formatnetwork.rst b/docs/formatnetwork.rst
index 6694a145af..1dd336211d 100644
--- a/docs/formatnetwork.rst
+++ b/docs/formatnetwork.rst
@@ -695,7 +695,7 @@ of 'route' or 'nat'.
<dns>
<txt name="example" value="example value"/>
<forwarder addr="8.8.8.8"/>
- <forwarder domain='example.com' addr="8.8.4.4"/>
+ <forwarder domain='example.com' addr='8.8.4.4' port='1234'/>
<forwarder domain='www.example.com'/>
<srv service='name' protocol='tcp' domain='test-domain-name' target='.'
port='1024' priority='10' weight='10'/>
@@ -762,8 +762,10 @@ of 'route' or 'nat'.
will be resolved locally (or via the host's standard DNS forwarding if
they can't be resolved locally). If an ``addr`` is specified by itself,
then all DNS requests to the network's DNS server will be forwarded to
the
- DNS server at that address with no exceptions. ``addr`` :since:`Since
- 1.1.3` , ``domain`` :since:`Since 2.2.0`.
+ DNS server at that address with no exceptions. Optionally, ``port``
+ attribute can be specified among with ``addr`` to specify a nonstandard
"Optionally, the ``port`` attribute can be given along with ...
(in case you're wondering about "given" - that's just to avoid using
variations of "specify" twice in the same sentence)
+ port of the DNS server. ``addr`` :since:`Since 1.1.3`, ``domain``
+ :since:`Since 2.2.0`, ``port`` :since:`Since 12.0.0`.
``txt``
A ``dns`` element can have 0 or more ``txt`` elements. Each txt element
defines a DNS TXT record and has two attributes, both required: a name
diff --git a/src/conf/network_conf.c b/src/conf/network_conf.c
index 8cd26de72f..fe44fd28c3 100644
--- a/src/conf/network_conf.c
+++ b/src/conf/network_conf.c
@@ -901,12 +901,32 @@ virNetworkDNSDefParseXML(const char *networkName,
for (i = 0; i < nfwds; i++) {
g_autofree char *addr = virXMLPropString(fwdNodes[i], "addr");
- if (addr && virSocketAddrParse(&def->forwarders[i].addr,
- addr, AF_UNSPEC) < 0) {
- virReportError(VIR_ERR_XML_ERROR,
- _("Invalid forwarder IP address '%1$s' in network
'%2$s'"),
- addr, networkName);
- return -1;
+ if (addr) {
+ int port = -1;
+ int rc;
+
+ if (virSocketAddrParse(&def->forwarders[i].addr,
+ addr, AF_UNSPEC) < 0) {
+ virReportError(VIR_ERR_XML_ERROR,
+ _("Invalid forwarder IP address '%1$s' in
network '%2$s'"),
+ addr, networkName);
+ return -1;
+ }
+
+ if ((rc = virXMLPropInt(fwdNodes[i], "port", 10,
+ VIR_XML_PROP_NONZERO |
+ VIR_XML_PROP_NONNEGATIVE,
+ &port, -1)) < 0) {
+ return -1;
+ } else if (rc > 0) {
+ if (port > 65535) {
+ virReportError(VIR_ERR_INVALID_ARG,
+ _("port '%1$d' out of range"), port);
+ return -1;
+ }
+
+ virSocketAddrSetPort(&def->forwarders[i].addr, port);
+ }
One validation hole is that if someone specifies a port without an
address, the port will just be ignored (and also not stored, so it will
just disappear from the config).
Otherwise
Reviewed-by: Laine Stump <[email protected]>
}
def->forwarders[i].domain = virXMLPropString(fwdNodes[i],
"domain");
if (!(addr || def->forwarders[i].domain)) {
@@ -1986,11 +2006,15 @@ virNetworkDNSDefFormat(virBuffer *buf,
}
if (VIR_SOCKET_ADDR_VALID(&def->forwarders[i].addr)) {
g_autofree char *addr =
virSocketAddrFormat(&def->forwarders[i].addr);
+ int port = virSocketAddrGetPort(&def->forwarders[i].addr);
if (!addr)
return -1;
virBufferAsprintf(buf, " addr='%s'", addr);
+
+ if (port > 0)
+ virBufferAsprintf(buf, " port='%d'", port);
}
virBufferAddLit(buf, "/>\n");
}
diff --git a/src/conf/schemas/network.rng b/src/conf/schemas/network.rng
index b7c8551fad..0d293af93b 100644
--- a/src/conf/schemas/network.rng
+++ b/src/conf/schemas/network.rng
@@ -287,6 +287,11 @@
<optional>
<attribute name="domain"><ref name="dnsName"/></attribute>
</optional>
+ <optional>
+ <attribute name="port">
+ <ref name="unsignedShort"/>
You could instead use <ref name="port"/> (which is defined as an integer
between 1 and 65535), but the only difference is that XML validation
would flag a "0" value, and the parser already does that (and provides a
much better error message) so it's kind of pointless (also I looked it
up and we don't consistently use "port"). (I guess I'm more wondering
why we bother having the special type in the RNG, rather than wondering
why you didn't use it - its value seems dubious :-P)
+ </attribute>
+ </optional>
<empty/>
</element>
</zeroOrMore>
diff --git a/tests/networkxml2xmlin/nat-network-dns-forwarders.xml
b/tests/networkxml2xmlin/nat-network-dns-forwarders.xml
index 426dd45cd9..dd22b686ab 100644
--- a/tests/networkxml2xmlin/nat-network-dns-forwarders.xml
+++ b/tests/networkxml2xmlin/nat-network-dns-forwarders.xml
@@ -6,7 +6,7 @@
<dns>
<forwarder addr='8.8.8.8'/>
<forwarder addr='8.8.4.4'/>
- <forwarder domain='example.com' addr='192.168.1.1'/>
+ <forwarder domain='example.com' addr='192.168.1.1' port='1234'/>
<forwarder domain='www.example.com'/>
</dns>
<ip address='192.168.122.1' netmask='255.255.255.0'>
diff --git a/tests/networkxml2xmlout/nat-network-dns-forwarders.xml
b/tests/networkxml2xmlout/nat-network-dns-forwarders.xml
index c05ad5514d..e03912750c 100644
--- a/tests/networkxml2xmlout/nat-network-dns-forwarders.xml
+++ b/tests/networkxml2xmlout/nat-network-dns-forwarders.xml
@@ -8,7 +8,7 @@
<dns>
<forwarder addr='8.8.8.8'/>
<forwarder addr='8.8.4.4'/>
- <forwarder domain='example.com' addr='192.168.1.1'/>
+ <forwarder domain='example.com' addr='192.168.1.1' port='1234'/>
<forwarder domain='www.example.com'/>
</dns>
<ip address='192.168.122.1' netmask='255.255.255.0'>
