[libvirt] [PATCH] Use the same MAC address that is defined in domain XML for attached-mac field.

[Ansis Atteka]

Currently libvirt sets the attached-mac to altered MAC address that has
first byte set to FE. This patch will change that behavior by using the
original (unaltered) MAC address from the domain XML configuration file.
---
 src/network/bridge_driver.c |    2 +-
 src/qemu/qemu_command.c     |    5 +----
 src/uml/uml_conf.c          |    5 +----
 src/util/virnetdevtap.c     |   11 ++++++++++-
 src/util/virnetdevtap.h     |    1 +
 5 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index 8575d3e..3e1e031 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -1766,7 +1766,7 @@ networkStartNetworkVirtual(struct network_driver *driver,
         }
         if (virNetDevTapCreateInBridgePort(network->def->bridge,
                                            &macTapIfName, network->def->mac,
-                                           0, false, NULL, NULL) < 0) {
+                                           false, 0, false, NULL, NULL) < 0) {
             VIR_FREE(macTapIfName);
             goto err0;
         }
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 5a34504..671054c 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -180,7 +180,6 @@ qemuNetworkIfaceConnect(virDomainDefPtr def,
     int tapfd = -1;
     int vnet_hdr = 0;
     bool template_ifname = false;
-    unsigned char tapmac[VIR_MAC_BUFLEN];
     int actualType = virDomainNetGetActualType(net);
 
     if (actualType == VIR_DOMAIN_NET_TYPE_NETWORK) {
@@ -244,9 +243,7 @@ qemuNetworkIfaceConnect(virDomainDefPtr def,
         net->model && STREQ(net->model, "virtio"))
         vnet_hdr = 1;
 
-    memcpy(tapmac, net->mac, VIR_MAC_BUFLEN);
-    tapmac[0] = 0xFE; /* Discourage bridge from using TAP dev MAC */
-    err = virNetDevTapCreateInBridgePort(brname, &net->ifname, tapmac,
+    err = virNetDevTapCreateInBridgePort(brname, &net->ifname, net->mac, true,
                                          vnet_hdr, true, &tapfd,
                                          virDomainNetGetActualVirtPortProfile(net));
     virDomainAuditNetDevice(def, net, "/dev/net/tun", tapfd >= 0);
diff --git a/src/uml/uml_conf.c b/src/uml/uml_conf.c
index dbbbfda..c7b29a0 100644
--- a/src/uml/uml_conf.c
+++ b/src/uml/uml_conf.c
@@ -127,7 +127,6 @@ umlConnectTapDevice(virConnectPtr conn,
                     const char *bridge)
 {
     bool template_ifname = false;
-    unsigned char tapmac[VIR_MAC_BUFLEN];
 
     if (!net->ifname ||
         STRPREFIX(net->ifname, VIR_NET_GENERATED_PREFIX) ||
@@ -139,9 +138,7 @@ umlConnectTapDevice(virConnectPtr conn,
         template_ifname = true;
     }
 
-    memcpy(tapmac, net->mac, VIR_MAC_BUFLEN);
-    tapmac[0] = 0xFE; /* Discourage bridge from using TAP dev MAC */
-    if (virNetDevTapCreateInBridgePort(bridge, &net->ifname, tapmac,
+    if (virNetDevTapCreateInBridgePort(bridge, &net->ifname, net->mac, true,
                                        0, true, NULL,
                                        virDomainNetGetActualVirtPortProfile(net)) < 0) {
         if (template_ifname)
diff --git a/src/util/virnetdevtap.c b/src/util/virnetdevtap.c
index 0fce08d..868ba57 100644
--- a/src/util/virnetdevtap.c
+++ b/src/util/virnetdevtap.c
@@ -22,6 +22,7 @@
 
 #include <config.h>
 
+#include "virmacaddr.h"
 #include "virnetdevtap.h"
 #include "virnetdev.h"
 #include "virnetdevbridge.h"
@@ -248,6 +249,7 @@ int virNetDevTapDelete(const char *ifname ATTRIBUTE_UNUSED)
  * @brname: the bridge name
  * @ifname: the interface name (or name template)
  * @macaddr: desired MAC address (VIR_MAC_BUFLEN long)
+ * @discourage: whether bridge should be discouraged from using macaddr
  * @vnet_hdr: whether to try enabling IFF_VNET_HDR
  * @tapfd: file descriptor return value for the new tap device
  * @virtPortProfile: bridge/port specific configuration
@@ -265,11 +267,14 @@ int virNetDevTapDelete(const char *ifname ATTRIBUTE_UNUSED)
 int virNetDevTapCreateInBridgePort(const char *brname,
                                    char **ifname,
                                    const unsigned char *macaddr,
+                                   bool discourage,
                                    int vnet_hdr,
                                    bool up,
                                    int *tapfd,
                                    virNetDevVPortProfilePtr virtPortProfile)
 {
+    unsigned char tapmac[VIR_MAC_BUFLEN];
+
     if (virNetDevTapCreate(ifname, vnet_hdr, tapfd) < 0)
         return -1;
 
@@ -279,7 +284,11 @@ int virNetDevTapCreateInBridgePort(const char *brname,
      * seeing the kernel allocate random MAC for the TAP
      * device before we set our static MAC.
      */
-    if (virNetDevSetMAC(*ifname, macaddr) < 0)
+    memcpy(tapmac, macaddr, VIR_MAC_BUFLEN);
+    if (discourage)
+        tapmac[0] = 0xFE; /* Discourage bridge from using TAP dev MAC */
+
+    if (virNetDevSetMAC(*ifname, tapmac) < 0)
         goto error;
 
     /* We need to set the interface MTU before adding it
diff --git a/src/util/virnetdevtap.h b/src/util/virnetdevtap.h
index 918f3dc..fc50e22 100644
--- a/src/util/virnetdevtap.h
+++ b/src/util/virnetdevtap.h
@@ -37,6 +37,7 @@ int virNetDevTapDelete(const char *ifname)
 int virNetDevTapCreateInBridgePort(const char *brname,
                                    char **ifname,
                                    const unsigned char *macaddr,
+                                   bool discourage,
                                    int vnet_hdr,
                                    bool up,
                                    int *tapfd,
-- 
1.7.5.4