nwfilter: add XML attribute to control iptables state match

This patch adds an optional XML attribute to a nwfilter rule to give the user control over whether the rule is supposed to be using the iptables state match or not. A rule may now look like shown in the XML below with the statematch attribute either having value '0' or 'false' (case-insensitive).

[...]
<rule action='accept' direction='in' statematch='false'>
<tcp srcmacaddr='1:2:3:4:5:6'
           srcipaddr='10.1.2.3' srcipmask='32'
           dscp='33'
           srcportstart='20' srcportend='21'
           dstportstart='100' dstportend='1111'/>
</rule>
[...]

I am also extending the nwfilter schema and add this attribute to a test case.

docs/schemas/nwfilter.rng

@@ -299,6 +299,11 @@
         <ref name='priority-type'/>
       </attribute>
     </optional>
+    <optional>
+      <attribute name="statematch">
+        <ref name='statematch-type'/>
+      </attribute>
+    </optional>
   </define>
 
   <define name="match-attribute">
@@ -816,4 +821,9 @@
         <param name="maxInclusive">1000</param>
       </data>
   </define>
+  <define name='statematch-type'>
+    <data type="string">
+      <param name="pattern">([Ff][Aa][Ll][Ss][Ee]|0)</param>
+    </data>
+  </define>
 </grammar>

src/conf/nwfilter_conf.c

@@ -1580,6 +1580,7 @@ virNWFilterRuleParse(xmlNodePtr node)
     char *action;
     char *direction;
     char *prio;
+    char *statematch;
     int found;
     int found_i = 0;
     unsigned int priority;
@@ -1595,6 +1596,7 @@ virNWFilterRuleParse(xmlNodePtr node)
     action    = virXMLPropString(node, "action");
     direction = virXMLPropString(node, "direction");
     prio      = virXMLPropString(node, "priority");
+    statematch= virXMLPropString(node, "statematch");
 
     if (!action) {
         virNWFilterReportError(VIR_ERR_INTERNAL_ERROR,
@@ -1633,6 +1635,10 @@ virNWFilterRuleParse(xmlNodePtr node)
         }
     }
 
+    if (statematch &&
+        (STREQ(statematch, "0") || STRCASEEQ(statematch, "false")))
+        ret->flags |= RULE_FLAG_NO_STATEMATCH;
+
     cur = node->children;
 
     found = 0;
@@ -1677,6 +1683,7 @@ cleanup:
     VIR_FREE(prio);
     VIR_FREE(action);
     VIR_FREE(direction);
+    VIR_FREE(statematch);
 
     return ret;
 
@@ -2532,6 +2539,9 @@ virNWFilterRuleDefFormat(virNWFilterRuleDefPtr def)
                       virNWFilterRuleDirectionTypeToString(def->tt),
                       def->priority);
 
+    if ((def->flags & RULE_FLAG_NO_STATEMATCH))
+        virBufferAddLit(&buf, " statematch='false'");
+
     i = 0;
     while (virAttr[i].id) {
         if (virAttr[i].prtclType == def->prtclType) {

src/conf/nwfilter_conf.h

@@ -345,11 +345,16 @@ enum virNWFilterEbtablesTableType {
 
 # define MAX_RULE_PRIORITY  1000
 
+enum virNWFilterRuleFlags {
+    RULE_FLAG_NO_STATEMATCH = (1 << 0),
+};
+
 
 typedef struct _virNWFilterRuleDef  virNWFilterRuleDef;
 typedef virNWFilterRuleDef *virNWFilterRuleDefPtr;
 struct _virNWFilterRuleDef {
     unsigned int priority;
+    enum virNWFilterRuleFlags flags;
     int action; /*enum virNWFilterRuleActionType*/
     int tt; /*enum virNWFilterRuleDirectionType*/
     enum virNWFilterRuleProtocolType prtclType;

src/nwfilter/nwfilter_ebiptables_driver.c

@@ -1498,6 +1498,9 @@ iptablesCreateRuleInstance(virNWFilterDefPtr nwfilter,
             needState = 0;
     }
 
+    if ((rule->flags & RULE_FLAG_NO_STATEMATCH))
+        needState = 0;
+
     chainPrefix[0] = 'F';
 
     maySkipICMP = directionIn || inout;

tests/nwfilterxml2xmlin/tcp-test.xml

@@ -5,14 +5,14 @@
           dstipaddr='10.1.2.3' dstipmask='255.255.255.255'
           dscp='2'/>
   </rule>
-  <rule action='accept' direction='in'>
+  <rule action='accept' direction='in' statematch='false'>
      <tcp srcmacaddr='1:2:3:4:5:6'
           srcipaddr='10.1.2.3' srcipmask='32'
           dscp='33'
           srcportstart='20' srcportend='21'
           dstportstart='100' dstportend='1111'/>
   </rule>
-  <rule action='accept' direction='in'>
+  <rule action='accept' direction='in' statematch='0'>
      <tcp srcmacaddr='1:2:3:4:5:6'
           srcipaddr='10.1.2.3' srcipmask='32'
           dscp='63'

tests/nwfilterxml2xmlout/tcp-test.xml

@@ -3,10 +3,10 @@
   <rule action='accept' direction='out' priority='500'>
     <tcp srcmacaddr='01:02:03:04:05:06' dstipaddr='10.1.2.3' dstipmask='32' dscp='2'/>
   </rule>
-  <rule action='accept' direction='in' priority='500'>
+  <rule action='accept' direction='in' priority='500' statematch='false'>
     <tcp srcmacaddr='01:02:03:04:05:06' srcipaddr='10.1.2.3' srcipmask='32' dscp='33' srcportstart='20' srcportend='21' dstportstart='100' dstportend='1111'/>
   </rule>
-  <rule action='accept' direction='in' priority='500'>
+  <rule action='accept' direction='in' priority='500' statematch='false'>
     <tcp srcmacaddr='01:02:03:04:05:06' srcipaddr='10.1.2.3' srcipmask='32' dscp='63' srcportstart='255' srcportend='256' dstportstart='65535'/>
   </rule>
 </filter>