nwfilter: wire up new APIs for creating and deleting nwfilter bindings

This allows the virsh commands nwfilter-binding-create and
nwfilter-binding-delete to be used.

Note using these commands lets you delete filters that were
previously created automatically by the virt drivers, or add
filters for VM nics that were not there before. Generally it
is expected these new APIs will only be used by virt drivers.
It is the admin's responsibility to not shoot themselves in
the foot.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

src/nwfilter/nwfilter_driver.c

@@ -787,6 +787,90 @@ nwfilterBindingGetXMLDesc(virNWFilterBindingPtr binding,
 }
 
 
+static virNWFilterBindingPtr
+nwfilterBindingCreateXML(virConnectPtr conn,
+                         const char *xml,
+                         unsigned int flags)
+{
+    virNWFilterBindingObjPtr obj;
+    virNWFilterBindingDefPtr def;
+    virNWFilterBindingPtr ret = NULL;
+
+    virCheckFlags(0, NULL);
+
+    def = virNWFilterBindingDefParseString(xml);
+    if (!def)
+        return NULL;
+
+    if (virNWFilterBindingCreateXMLEnsureACL(conn, def) < 0)
+        goto cleanup;
+
+    obj = virNWFilterBindingObjListFindByPortDev(driver->bindings, def->portdevname);
+    if (obj) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Filter already present for NIC %s"), def->portdevname);
+        goto cleanup;
+    }
+
+    obj = virNWFilterBindingObjListAdd(driver->bindings,
+                                       def);
+    if (!obj)
+        goto cleanup;
+
+    if (!(ret = virGetNWFilterBinding(conn, def->portdevname, def->filter)))
+        goto cleanup;
+
+    if (virNWFilterInstantiateFilter(driver, def) < 0) {
+        virNWFilterBindingObjListRemove(driver->bindings, obj);
+        virObjectUnref(ret);
+        ret = NULL;
+        goto cleanup;
+    }
+    virNWFilterBindingObjSave(obj, driver->bindingDir);
+
+ cleanup:
+    if (!obj)
+        virNWFilterBindingDefFree(def);
+    virNWFilterBindingObjEndAPI(&obj);
+
+    return ret;
+}
+
+
+/*
+ * Note that this is primarily intended for usage by the hypervisor
+ * drivers. it is exposed to the admin, however, and nothing stops
+ * an admin from deleting filter bindings created by the hypervisor
+ * drivers. IOW, it is the admin's responsibility not to shoot
+ * themself in the foot
+ */
+static int
+nwfilterBindingDelete(virNWFilterBindingPtr binding)
+{
+    virNWFilterBindingObjPtr obj;
+    virNWFilterBindingDefPtr def;
+    int ret = -1;
+
+    obj = virNWFilterBindingObjListFindByPortDev(driver->bindings, binding->portdev);
+    if (!obj)
+        return -1;
+
+    def = virNWFilterBindingObjGetDef(obj);
+    if (virNWFilterBindingDeleteEnsureACL(binding->conn, def) < 0)
+        goto cleanup;
+
+    virNWFilterTeardownFilter(def);
+    virNWFilterBindingObjDelete(obj, driver->bindingDir);
+    virNWFilterBindingObjListRemove(driver->bindings, obj);
+
+    ret = 0;
+
+ cleanup:
+    virNWFilterBindingObjEndAPI(&obj);
+    return ret;
+}
+
+
 static virNWFilterDriver nwfilterDriver = {
     .name = "nwfilter",
     .connectNumOfNWFilters = nwfilterConnectNumOfNWFilters, /* 0.8.0 */
@@ -800,6 +884,8 @@ static virNWFilterDriver nwfilterDriver = {
     .nwfilterBindingLookupByPortDev = nwfilterBindingLookupByPortDev, /* 4.5.0 */
     .connectListAllNWFilterBindings = nwfilterConnectListAllNWFilterBindings, /* 4.5.0 */
     .nwfilterBindingGetXMLDesc = nwfilterBindingGetXMLDesc, /* 4.5.0 */
+    .nwfilterBindingCreateXML = nwfilterBindingCreateXML, /* 4.5.0 */
+    .nwfilterBindingDelete = nwfilterBindingDelete, /* 4.5.0 */
 };