Add '<nat>' element to '<forward>' network schemas

Commits 905629f4 and 1716e7a6 have added support for specifying
an IPv4 range and a port range to be used by NAT:
<forward mode='nat'>
  <nat>
    <address start='10.20.30.40' end='10.20.30.44'/>
    <port start='60000' end='65432'/>
  </nat>
</forward>

https://bugzilla.redhat.com/show_bug.cgi?id=1004364

docs/schemas/network.rng

@@ -160,6 +160,32 @@
                   <empty/>
                 </element>
               </optional>
+              <optional>
+                <element name='nat'>
+                  <interleave>
+                    <optional>
+                      <element name='address'>
+                        <attribute name='start'>
+                          <ref name='ipv4Addr'/>
+                        </attribute>
+                        <attribute name='end'>
+                          <ref name='ipv4Addr'/>
+                        </attribute>
+                      </element>
+                    </optional>
+                    <optional>
+                      <element name='port'>
+                        <attribute name='start'>
+                          <ref name='port'/>
+                        </attribute>
+                        <attribute name='end'>
+                          <ref name='port'/>
+                        </attribute>
+                      </element>
+                    </optional>
+                  </interleave>
+                </element>
+              </optional>
             </interleave>
           </element>
         </optional>

docs/schemas/networkcommon.rng

@@ -217,4 +217,11 @@
       </oneOrMore>
     </element>
   </define>
+
+  <define name='port'>
+    <data type='integer'>
+      <param name='minInclusive'>1</param>
+      <param name='maxInclusive'>65535</param>
+    </data>
+  </define>
 </grammar>

tests/networkxml2xmlin/nat-network-forward-nat-address.xml

+<network>
+  <name>default</name>
+  <uuid>81ff0d90-c91e-6742-64da-4a736edb9a9b</uuid>
+  <bridge name="virbr0"/>
+  <forward mode="nat" dev="eth1">
+    <nat>
+      <address start='10.20.30.40' end='10.20.30.44'/>
+      <port start='60000' end='65432'/>
+    </nat>
+  </forward>
+  <ip address="192.168.122.1" netmask="255.255.255.0">
+    <dhcp>
+      <range start="192.168.122.2" end="192.168.122.254"/>
+      <host mac="00:16:3e:77:e2:ed" name="a.example.com" ip="192.168.122.10"/>
+      <host mac="00:16:3e:3e:a9:1a" name="b.example.com" ip="192.168.122.11"/>
+    </dhcp>
+  </ip>
+  <ip family="ipv4" address="192.168.123.1" netmask="255.255.255.0">
+  </ip>
+  <ip family="ipv6" address="2001:db8:ac10:fe01::1" prefix="64">
+  </ip>
+  <ip family="ipv6" address="2001:db8:ac10:fd01::1" prefix="64">
+  </ip>
+  <ip family="ipv4" address="10.24.10.1">
+  </ip>
+</network>

tests/networkxml2xmlout/nat-network-forward-nat-address.xml

+<network>
+  <name>default</name>
+  <uuid>81ff0d90-c91e-6742-64da-4a736edb9a9b</uuid>
+  <forward dev='eth1' mode='nat'>
+    <nat>
+      <address start='10.20.30.40' end='10.20.30.44'/>
+      <port start='60000' end='65432'/>
+    </nat>
+    <interface dev='eth1'/>
+  </forward>
+  <bridge name='virbr0' stp='on' delay='0'/>
+  <ip address='192.168.122.1' netmask='255.255.255.0'>
+    <dhcp>
+      <range start='192.168.122.2' end='192.168.122.254'/>
+      <host mac='00:16:3e:77:e2:ed' name='a.example.com' ip='192.168.122.10'/>
+      <host mac='00:16:3e:3e:a9:1a' name='b.example.com' ip='192.168.122.11'/>
+    </dhcp>
+  </ip>
+  <ip family='ipv4' address='192.168.123.1' netmask='255.255.255.0'>
+  </ip>
+  <ip family='ipv6' address='2001:db8:ac10:fe01::1' prefix='64'>
+  </ip>
+  <ip family='ipv6' address='2001:db8:ac10:fd01::1' prefix='64'>
+  </ip>
+  <ip family='ipv4' address='10.24.10.1'>
+  </ip>
+</network>

tests/networkxml2xmltest.c

@@ -108,6 +108,7 @@ mymain(void)
     DO_TEST("nat-network-dns-srv-record-minimal");
     DO_TEST("nat-network-dns-hosts");
     DO_TEST("nat-network-dns-forward-plain");
+    DO_TEST("nat-network-forward-nat-address");
     DO_TEST("8021Qbh-net");
     DO_TEST("direct-net");
     DO_TEST("host-bridge-net");