[libvirt] [PATCH] nwfilter: enable rejection of packets

[Stefan Berger]

This patch adds the possibility to not just drop packets, but to also 
have them rejected where iptables at least sends an ICMP msg back to the 
originator. On ebtables this again maps into dropping packets since 
rejecting is not supported.

I am adding 'since 0.8.9' to the docs assuming this will be the next 
version of libvirt.

Signed-off-by: Stefan Berger <stefanb at us.ibm.com>

---
  docs/formatnwfilter.html.in               |    8 +++++---
  docs/schemas/nwfilter.rng                 |    1 +
  src/conf/nwfilter_conf.c                  |    6 ++++--
  src/conf/nwfilter_conf.h                  |    1 +
  src/nwfilter/nwfilter_ebiptables_driver.c |   15 +++++++++++++--
  5 files changed, 24 insertions(+), 7 deletions(-)

Index: libvirt-acl/src/conf/nwfilter_conf.c
===================================================================
--- libvirt-acl.orig/src/conf/nwfilter_conf.c
+++ libvirt-acl/src/conf/nwfilter_conf.c
@@ -53,11 +53,13 @@

  VIR_ENUM_IMPL(virNWFilterRuleAction, VIR_NWFILTER_RULE_ACTION_LAST,
                "drop",
-              "accept");
+              "accept",
+              "reject");

  VIR_ENUM_IMPL(virNWFilterJumpTarget, VIR_NWFILTER_RULE_ACTION_LAST,
                "DROP",
-              "ACCEPT");
+              "ACCEPT",
+              "REJECT");

  VIR_ENUM_IMPL(virNWFilterRuleDirection, VIR_NWFILTER_RULE_DIRECTION_LAST,
                "in",
Index: libvirt-acl/src/conf/nwfilter_conf.h
===================================================================
--- libvirt-acl.orig/src/conf/nwfilter_conf.h
+++ libvirt-acl/src/conf/nwfilter_conf.h
@@ -291,6 +291,7 @@ struct _udpliteHdrFilterDef {
  enum virNWFilterRuleActionType {
      VIR_NWFILTER_RULE_ACTION_DROP = 0,
      VIR_NWFILTER_RULE_ACTION_ACCEPT,
+    VIR_NWFILTER_RULE_ACTION_REJECT,

      VIR_NWFILTER_RULE_ACTION_LAST,
  };
Index: libvirt-acl/src/nwfilter/nwfilter_ebiptables_driver.c
===================================================================
--- libvirt-acl.orig/src/nwfilter/nwfilter_ebiptables_driver.c
+++ libvirt-acl/src/nwfilter/nwfilter_ebiptables_driver.c
@@ -1516,7 +1516,7 @@ _iptablesCreateRuleInstance(int directio
      if (rule->action == VIR_NWFILTER_RULE_ACTION_ACCEPT)
          target = accept_target;
      else {
-        target = "DROP";
+        target = virNWFilterJumpTargetTypeToString(rule->action);
          skipMatch = defMatch;
      }

@@ -1880,6 +1880,7 @@ ebtablesCreateRuleInstance(char chainPre
           number[20];
      char chain[MAX_CHAINNAME_LENGTH];
      virBuffer buf = VIR_BUFFER_INITIALIZER;
+    const char *target;

      if (!ebtables_cmd_path) {
          virNWFilterReportError(VIR_ERR_INTERNAL_ERROR, "%s",
@@ -2295,10 +2296,20 @@ ebtablesCreateRuleInstance(char chainPre
          return -1;
      }

+    switch (rule->action) {
+    case VIR_NWFILTER_RULE_ACTION_REJECT:
+        /* REJECT not supported */
+        target = virNWFilterJumpTargetTypeToString(
+                                     VIR_NWFILTER_RULE_ACTION_DROP);
+    break;
+    default:
+        target = virNWFilterJumpTargetTypeToString(rule->action);
+    }
+
      virBufferVSprintf(&buf,
                        " -j %s" CMD_DEF_POST CMD_SEPARATOR
                        CMD_EXEC,
-                      virNWFilterJumpTargetTypeToString(rule->action));
+                      target);

      if (virBufferError(&buf)) {
          virBufferFreeAndReset(&buf);
Index: libvirt-acl/docs/schemas/nwfilter.rng
===================================================================
--- libvirt-acl.orig/docs/schemas/nwfilter.rng
+++ libvirt-acl/docs/schemas/nwfilter.rng
@@ -839,6 +839,7 @@
<choice>
<value>drop</value>
<value>accept</value>
+ <value>reject</value>
</choice>
</define>

Index: libvirt-acl/docs/formatnwfilter.html.in
===================================================================
--- libvirt-acl.orig/docs/formatnwfilter.html.in
+++ libvirt-acl/docs/formatnwfilter.html.in
@@ -260,9 +260,11 @@
</p>
<ul>
<li>
-        action -- mandatory; must either be <code>drop</code> or 
<code>accept</code> if
-        the evaluation of the filtering rule is supposed to drop or accept
-        a packet
+        action -- mandatory; must either be <code>drop</code>,
+ <code>reject</code><span class="since">(since 0.8.9)</span>,
+        or <code>accept</code> if
+        the evaluation of the filtering rule is supposed to drop,
+        reject (using ICMP message), or accept a packet
</li>
<li>
          direction -- mandatory; must either be <code>in</code>, 
<code>out</code> or