Pass the VM's UUID into the nwfilter subsystem

A preparatory patch for DHCP snooping where we want to be able to
differentiate between a VM's interface using the tuple of
<VM UUID, Interface MAC address>. We assume that MAC addresses could
possibly be re-used between different networks (VLANs) thus do not only
want to rely on the MAC address to identify an interface.

At the current 'final destination' in virNWFilterInstantiate I am leaving
the vmuuid parameter as ATTRIBUTE_UNUSED until the DHCP snooping patches arrive.
(we may not post the DHCP snooping patches for 0.9.9, though)

Mostly this is a pretty trivial patch. On the lowest layers, in lxc_driver
and uml_conf, I am passing the virDomainDefPtr around until I am passing
only the VM's uuid into the NWFilter calls.

src/conf/domain_nwfilter.c

@@ -37,9 +37,10 @@ virDomainConfNWFilterRegister(virDomainConfNWFilterDriverPtr driver) {
 
 int
 virDomainConfNWFilterInstantiate(virConnectPtr conn,
+                                 const unsigned char *vmuuid,
                                  virDomainNetDefPtr net) {
     if (nwfilterDriver != NULL)
-        return nwfilterDriver->instantiateFilter(conn, net);
+        return nwfilterDriver->instantiateFilter(conn, vmuuid, net);
     /* driver module not available -- don't indicate failure */
     return 0;
 }

src/conf/domain_nwfilter.h

@@ -24,6 +24,7 @@
 # define DOMAIN_NWFILTER_H
 
 typedef int (*virDomainConfInstantiateNWFilter)(virConnectPtr conn,
+                                                const unsigned char *vmuuid,
                                                 virDomainNetDefPtr net);
 typedef void (*virDomainConfTeardownNWFilter)(virDomainNetDefPtr net);
 
@@ -36,6 +37,7 @@ typedef virDomainConfNWFilterDriver *virDomainConfNWFilterDriverPtr;
 void virDomainConfNWFilterRegister(virDomainConfNWFilterDriverPtr driver);
 
 int virDomainConfNWFilterInstantiate(virConnectPtr conn,
+                                     const unsigned char *vmuuid,
                                      virDomainNetDefPtr net);
 void virDomainConfNWFilterTeardown(virDomainNetDefPtr net);
 void virDomainConfVMNWFilterTeardown(virDomainObjPtr vm);

src/lxc/lxc_driver.c

@@ -1185,6 +1185,7 @@ static void lxcVmCleanup(lxc_driver_t *driver,
 
 
 static int lxcSetupInterfaceBridged(virConnectPtr conn,
+                                    virDomainDefPtr vm,
                                     virDomainNetDefPtr net,
                                     const char *brname,
                                     unsigned int *nveths,
@@ -1229,7 +1230,7 @@ static int lxcSetupInterfaceBridged(virConnectPtr conn,
     }
 
     if (net->filter &&
-        virDomainConfNWFilterInstantiate(conn, net) < 0)
+        virDomainConfNWFilterInstantiate(conn, vm->uuid, net) < 0)
         goto cleanup;
 
     ret = 0;
@@ -1349,6 +1350,7 @@ static int lxcSetupInterfaces(virConnectPtr conn,
                 goto cleanup;
 
             if (lxcSetupInterfaceBridged(conn,
+                                         def,
                                          def->nets[i],
                                          brname,
                                          nveths,
@@ -1367,6 +1369,7 @@ static int lxcSetupInterfaces(virConnectPtr conn,
                 goto cleanup;
             }
             if (lxcSetupInterfaceBridged(conn,
+                                         def,
                                          def->nets[i],
                                          brname,
                                          nveths,

src/nwfilter/nwfilter_driver.c

@@ -443,8 +443,10 @@ cleanup:
 
 static int
 nwfilterInstantiateFilter(virConnectPtr conn,
-                          virDomainNetDefPtr net) {
-    return virNWFilterInstantiateFilter(conn, net);
+                          const unsigned char *vmuuid,
+                          virDomainNetDefPtr net)
+{
+    return virNWFilterInstantiateFilter(conn, vmuuid, net);
 }
 
 

src/nwfilter/nwfilter_gentech_driver.c

@@ -607,6 +607,7 @@ virNWFilterRuleInstancesToArray(int nEntries,
 
 /**
  * virNWFilterInstantiate:
+ * @vmuuid: The UUID of the VM
  * @techdriver: The driver to use for instantiation
  * @filter: The filter to instantiate
  * @ifname: The name of the interface to apply the rules to
@@ -625,7 +626,8 @@ virNWFilterRuleInstancesToArray(int nEntries,
  * Call this function while holding the NWFilter filter update lock
  */
 static int
-virNWFilterInstantiate(virNWFilterTechDriverPtr techdriver,
+virNWFilterInstantiate(const unsigned char *vmuuid ATTRIBUTE_UNUSED,
+                       virNWFilterTechDriverPtr techdriver,
                        enum virDomainNetType nettype,
                        virNWFilterDefPtr filter,
                        const char *ifname,
@@ -761,7 +763,8 @@ err_unresolvable_vars:
  * Call this function while holding the NWFilter filter update lock
  */
 static int
-__virNWFilterInstantiateFilter(bool teardownOld,
+__virNWFilterInstantiateFilter(const unsigned char *vmuuid,
+                               bool teardownOld,
                                const char *ifname,
                                int ifindex,
                                const char *linkdev,
@@ -853,7 +856,8 @@ __virNWFilterInstantiateFilter(bool teardownOld,
     break;
     }
 
-    rc = virNWFilterInstantiate(techdriver,
+    rc = virNWFilterInstantiate(vmuuid,
+                                techdriver,
                                 nettype,
                                 filter,
                                 ifname,
@@ -883,6 +887,7 @@ err_exit:
 
 static int
 _virNWFilterInstantiateFilter(virConnectPtr conn,
+                              const unsigned char *vmuuid,
                               const virDomainNetDefPtr net,
                               bool teardownOld,
                               enum instCase useNewFilter,
@@ -908,7 +913,8 @@ _virNWFilterInstantiateFilter(virConnectPtr conn,
         goto cleanup;
     }
 
-    rc = __virNWFilterInstantiateFilter(teardownOld,
+    rc = __virNWFilterInstantiateFilter(vmuuid,
+                                        teardownOld,
                                         net->ifname,
                                         ifindex,
                                         linkdev,
@@ -929,7 +935,8 @@ cleanup:
 
 
 int
-virNWFilterInstantiateFilterLate(const char *ifname,
+virNWFilterInstantiateFilterLate(const unsigned char *vmuuid,
+                                 const char *ifname,
                                  int ifindex,
                                  const char *linkdev,
                                  enum virDomainNetType nettype,
@@ -943,7 +950,8 @@ virNWFilterInstantiateFilterLate(const char *ifname,
 
     virNWFilterLockFilterUpdates();
 
-    rc = __virNWFilterInstantiateFilter(true,
+    rc = __virNWFilterInstantiateFilter(vmuuid,
+                                        true,
                                         ifname,
                                         ifindex,
                                         linkdev,
@@ -973,11 +981,12 @@ virNWFilterInstantiateFilterLate(const char *ifname,
 
 int
 virNWFilterInstantiateFilter(virConnectPtr conn,
+                             const unsigned char *vmuuid,
                              const virDomainNetDefPtr net)
 {
     bool foundNewFilter = false;
 
-    return _virNWFilterInstantiateFilter(conn, net,
+    return _virNWFilterInstantiateFilter(conn, vmuuid, net,
                                          1,
                                          INSTANTIATE_ALWAYS,
                                          &foundNewFilter);
@@ -986,12 +995,13 @@ virNWFilterInstantiateFilter(virConnectPtr conn,
 
 int
 virNWFilterUpdateInstantiateFilter(virConnectPtr conn,
+                                   const unsigned char *vmuuid,
                                    const virDomainNetDefPtr net,
                                    bool *skipIface)
 {
     bool foundNewFilter = false;
 
-    int rc = _virNWFilterInstantiateFilter(conn, net,
+    int rc = _virNWFilterInstantiateFilter(conn, vmuuid, net,
                                            0,
                                            INSTANTIATE_FOLLOW_NEWFILTER,
                                            &foundNewFilter);
@@ -1109,6 +1119,7 @@ virNWFilterDomainFWUpdateCB(void *payload,
                 switch (cb->step) {
                 case STEP_APPLY_NEW:
                     cb->err = virNWFilterUpdateInstantiateFilter(cb->conn,
+                                                                 vm->uuid,
                                                                  net,
                                                                  &skipIface);
                     if (cb->err == 0 && skipIface) {

src/nwfilter/nwfilter_gentech_driver.h

@@ -38,12 +38,15 @@ enum instCase {
 
 
 int virNWFilterInstantiateFilter(virConnectPtr conn,
+                                 const unsigned char *vmuuid,
                                  const virDomainNetDefPtr net);
 int virNWFilterUpdateInstantiateFilter(virConnectPtr conn,
+                                       const unsigned char *vmuuid,
                                        const virDomainNetDefPtr net,
                                        bool *skipIface);
 
-int virNWFilterInstantiateFilterLate(const char *ifname,
+int virNWFilterInstantiateFilterLate(const unsigned char *vmuuid,
+                                     const char *ifname,
                                      int ifindex,
                                      const char *linkdev,
                                      enum virDomainNetType nettype,

src/nwfilter/nwfilter_learnipaddr.c

@@ -704,7 +704,8 @@ learnIPAddressThread(void *arg)
                           "cache for interface %s"), inetaddr, req->ifname);
             }
 
-            ret = virNWFilterInstantiateFilterLate(req->ifname,
+            ret = virNWFilterInstantiateFilterLate(NULL,
+                                                   req->ifname,
                                                    req->ifindex,
                                                    req->linkdev,
                                                    req->nettype,

src/qemu/qemu_command.c

@@ -275,7 +275,7 @@ qemuNetworkIfaceConnect(virDomainDefPtr def,
 
     if (tapfd >= 0) {
         if ((net->filter) && (net->ifname)) {
-            if (virDomainConfNWFilterInstantiate(conn, net) < 0)
+            if (virDomainConfNWFilterInstantiate(conn, def->uuid, net) < 0)
                 VIR_FORCE_CLOSE(tapfd);
         }
     }

src/qemu/qemu_process.c

@@ -2355,7 +2355,7 @@ qemuProcessFiltersInstantiate(virConnectPtr conn,
     for (i = 0 ; i < def->nnets ; i++) {
         virDomainNetDefPtr net = def->nets[i];
         if ((net->filter) && (net->ifname)) {
-           if (virDomainConfNWFilterInstantiate(conn, net) < 0) {
+           if (virDomainConfNWFilterInstantiate(conn, def->uuid, net) < 0) {
                 err = 1;
                 break;
             }

src/uml/uml_conf.c

@@ -122,6 +122,7 @@ virCapsPtr umlCapsInit(void) {
 
 static int
 umlConnectTapDevice(virConnectPtr conn,
+                    virDomainDefPtr vm,
                     virDomainNetDefPtr net,
                     const char *bridge)
 {
@@ -148,7 +149,7 @@ umlConnectTapDevice(virConnectPtr conn,
     }
 
     if (net->filter) {
-        if (virDomainConfNWFilterInstantiate(conn, net) < 0) {
+        if (virDomainConfNWFilterInstantiate(conn, vm->uuid, net) < 0) {
             if (template_ifname)
                 VIR_FREE(net->ifname);
             goto error;
@@ -165,6 +166,7 @@ error:
 
 static char *
 umlBuildCommandLineNet(virConnectPtr conn,
+                       virDomainDefPtr vm,
                        virDomainNetDefPtr def,
                        int idx)
 {
@@ -230,7 +232,7 @@ umlBuildCommandLineNet(virConnectPtr conn,
             goto error;
         }
 
-        if (umlConnectTapDevice(conn, def, bridge) < 0) {
+        if (umlConnectTapDevice(conn, vm, def, bridge) < 0) {
             VIR_FREE(bridge);
             goto error;
         }
@@ -241,7 +243,8 @@ umlBuildCommandLineNet(virConnectPtr conn,
     }
 
     case VIR_DOMAIN_NET_TYPE_BRIDGE:
-        if (umlConnectTapDevice(conn, def, def->data.bridge.brname) < 0)
+        if (umlConnectTapDevice(conn, vm, def,
+                                def->data.bridge.brname) < 0)
             goto error;
 
         /* ethNNN=tuntap,tapname,macaddr,gateway */
@@ -434,7 +437,7 @@ virCommandPtr umlBuildCommandLine(virConnectPtr conn,
     }
 
     for (i = 0 ; i < vm->def->nnets ; i++) {
-        char *ret = umlBuildCommandLineNet(conn, vm->def->nets[i], i);
+        char *ret = umlBuildCommandLineNet(conn, vm->def, vm->def->nets[i], i);
         if (!ret)
             goto error;
         virCommandAddArg(cmd, ret);