[ipxe-devel] [PATCH 03/10] ethernet: do not construct EUI-64 identifier for empty MAC

[Hannes Reinecke]

If the MAC address is empty we should not construct an EUI-64
identifier, but rather return an error.

Signed-off-by: Hannes Reinecke <hare at suse.de>
---
 src/net/ethernet.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/net/ethernet.c b/src/net/ethernet.c
index 33e0572..cb4febe 100644
--- a/src/net/ethernet.c
+++ b/src/net/ethernet.c
@@ -46,6 +46,9 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 /** Ethernet broadcast MAC address */
 uint8_t eth_broadcast[ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
 
+/** Empty Ethernet MAC address */
+uint8_t eth_empty[ETH_ALEN];
+
 /**
  * Add Ethernet link-layer header
  *
@@ -198,7 +201,8 @@ int eth_eth_addr ( const void *ll_addr, void *eth_addr ) {
  * @ret rc		Return status code
  */
 int eth_eui64 ( const void *ll_addr, void *eui64 ) {
-
+	if (!memcmp(ll_addr, eth_empty, ETH_ALEN))
+		return -ENXIO;
 	memcpy ( ( eui64 + 0 ), ( ll_addr + 0 ), 3 );
 	memcpy ( ( eui64 + 5 ), ( ll_addr + 3 ), 3 );
 	*( ( uint16_t * ) ( eui64 + 3 ) ) = htons ( 0xfffe );
-- 
1.8.4.5