Random Ethernet addresses should be private and should not be multicast.

[openvswitch] / include / packets.h

diff --git a/include/packets.h b/include/packets.h
index 83b71849244d28b629d96e1e247e26ec88fedf52..bad36712d3fb96af550e156a65bfd2c3d7cd99b6 100644 (file)
--- a/include/packets.h
+++ b/include/packets.h
@@ -86,6 +86,8 @@ static inline void eth_addr_from_uint64(uint64_t x, uint8_t ea[ETH_ADDR_LEN])
 static inline void eth_addr_random(uint8_t ea[ETH_ADDR_LEN])
 {
     random_bytes(ea, ETH_ADDR_LEN);
+    ea[0] &= ~1;                /* Unicast. */
+    ea[0] |= 2;                 /* Private. */
 }
 
 #define ETH_ADDR_FMT                                                    \
@@ -138,7 +140,8 @@ struct llc_snap_header {
 } __attribute__((packed));
 BUILD_ASSERT_DECL(LLC_SNAP_HEADER_LEN == sizeof(struct llc_snap_header));
 
-#define VLAN_VID 0x0fff
+#define VLAN_VID_MASK 0x0fff
+#define VLAN_PCP_MASK 0xe000
 
 #define VLAN_HEADER_LEN 4
 struct vlan_header {