[netdevice] Allow the hardware and link-layer addresses to differ in size

IPoIB has a 20-byte link-layer address, of which only eight bytes
represent anything relating to a "hardware address".

The PXE and EFI SNP APIs expect the permanent address to be the same
size as the link-layer address, so fill in the "permanent address"
field with the initial link layer address (as generated by
register_netdev() based upon the real hardware address).

src/arch/i386/interface/pxe/pxe_undi.c

@@ -412,6 +412,7 @@ PXENV_EXIT_t pxenv_undi_get_information ( struct s_PXENV_UNDI_GET_INFORMATION
 					  *undi_get_information ) {
 	struct device *dev = pxe_netdev->dev;
 	struct ll_protocol *ll_protocol = pxe_netdev->ll_protocol;
+	size_t ll_addr_len = ll_protocol->ll_addr_len;
 
 	DBG ( "PXENV_UNDI_GET_INFORMATION" );
 
@@ -420,13 +421,14 @@ PXENV_EXIT_t pxenv_undi_get_information ( struct s_PXENV_UNDI_GET_INFORMATION
 	/* Cheat: assume all cards can cope with this */
 	undi_get_information->MaxTranUnit = ETH_MAX_MTU;
 	undi_get_information->HwType = ntohs ( ll_protocol->ll_proto );
-	undi_get_information->HwAddrLen = ll_protocol->ll_addr_len;
+	undi_get_information->HwAddrLen = ll_addr_len;
+	assert ( ll_addr_len <=
+		 sizeof ( undi_get_information->CurrentNodeAddress ) );
 	memcpy ( &undi_get_information->CurrentNodeAddress,
 		 pxe_netdev->ll_addr,
 		 sizeof ( undi_get_information->CurrentNodeAddress ) );
-	memcpy ( &undi_get_information->PermNodeAddress,
+	ll_protocol->init_addr ( pxe_netdev->hw_addr,
-		 pxe_netdev->hw_addr,
+				 &undi_get_information->PermNodeAddress );
-		 sizeof ( undi_get_information->PermNodeAddress ) );
 	undi_get_information->ROMAddress = 0;
 		/* nic.rom_info->rom_segment; */
 	/* We only provide the ability to receive or transmit a single

src/drivers/net/ipoib.c

@@ -250,7 +250,21 @@ static int ipoib_pull ( struct net_device *netdev,
 }
 
 /**
- * Transcribe IPoIB address
+ * Initialise IPoIB link-layer address
+ *
+ * @v hw_addr		Hardware address
+ * @v ll_addr		Link-layer address
+ */
+static void ipoib_init_addr ( const void *hw_addr, void *ll_addr ) {
+	const struct ib_gid_half *guid = hw_addr;
+	struct ipoib_mac *mac = ll_addr;
+
+	memset ( mac, 0, sizeof ( *mac ) );
+	memcpy ( &mac->gid.u.half[1], guid, sizeof ( mac->gid.u.half[1] ) );
+}
+
+/**
+ * Transcribe IPoIB link-layer address
  *
  * @v ll_addr	Link-layer address
  * @ret string	Link-layer address in human-readable format
@@ -286,10 +300,12 @@ static int ipoib_mc_hash ( unsigned int af __unused,
 struct ll_protocol ipoib_protocol __ll_protocol = {
 	.name		= "IPoIB",
 	.ll_proto	= htons ( ARPHRD_INFINIBAND ),
+	.hw_addr_len	= sizeof ( struct ib_gid_half ),
 	.ll_addr_len	= IPOIB_ALEN,
 	.ll_header_len	= IPOIB_HLEN,
 	.push		= ipoib_push,
 	.pull		= ipoib_pull,
+	.init_addr	= ipoib_init_addr,
 	.ntoa		= ipoib_ntoa,
 	.mc_hash	= ipoib_mc_hash,
 };
@@ -653,7 +669,6 @@ void ipoib_link_state_changed ( struct ib_device *ibdev ) {
 int ipoib_probe ( struct ib_device *ibdev ) {
 	struct net_device *netdev;
 	struct ipoib_device *ipoib;
-	struct ipoib_mac *mac;
 	int rc;
 
 	/* Allocate network device */
@@ -669,9 +684,8 @@ int ipoib_probe ( struct ib_device *ibdev ) {
 	ipoib->ibdev = ibdev;
 
 	/* Extract hardware address */
-	mac = ( ( struct ipoib_mac * ) netdev->hw_addr );
+	memcpy ( netdev->hw_addr, &ibdev->gid.u.half[1],
-	memcpy ( &mac->gid.u.half[1], &ibdev->gid.u.half[1],
+		 sizeof ( ibdev->gid.u.half[1] ) );
-		 sizeof ( mac->gid.u.half[1] ) );
 
 	/* Set default broadcast address */
 	memcpy ( &ipoib->broadcast, &ipoib_broadcast,

src/include/gpxe/ethernet.h

@@ -11,6 +11,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 
 #include <stdint.h>
 
+extern void eth_init_addr ( const void *hw_addr, void *ll_addr );
 extern const char * eth_ntoa ( const void *ll_addr );
 extern struct net_device * alloc_etherdev ( size_t priv_size );
 

src/include/gpxe/netdevice.h

@@ -21,6 +21,12 @@ struct net_protocol;
 struct ll_protocol;
 struct device;
 
+/** Maximum length of a hardware address
+ *
+ * The longest currently-supported link-layer address is for IPoIB.
+ */
+#define MAX_HW_ADDR_LEN 8
+
 /** Maximum length of a link-layer address
  *
  * The longest currently-supported link-layer address is for IPoIB.
@@ -112,6 +118,13 @@ struct ll_protocol {
 	int ( * pull ) ( struct net_device *netdev, struct io_buffer *iobuf,
 			 const void **ll_dest, const void **ll_source,
 			 uint16_t *net_proto );
+	/**
+	 * Initialise link-layer address
+	 *
+	 * @v hw_addr		Hardware address
+	 * @v ll_addr		Link-layer address to fill in
+	 */
+	void ( * init_addr ) ( const void *hw_addr, void *ll_addr );
 	/**
 	 * Transcribe link-layer address
 	 *
@@ -124,7 +137,7 @@ struct ll_protocol {
 	 * The buffer used to hold the transcription is statically
 	 * allocated.
 	 */
-	const char * ( * ntoa ) ( const void * ll_addr );
+	const char * ( * ntoa ) ( const void *ll_addr );
 	/**
 	 * Hash multicast address
 	 *
@@ -140,6 +153,8 @@ struct ll_protocol {
 	 * This is an ARPHRD_XXX constant, in network byte order.
 	 */
 	uint16_t ll_proto;
+	/** Hardware address length */
+	uint8_t hw_addr_len;
 	/** Link-layer address length */
 	uint8_t ll_addr_len;
 	/** Link-layer header length */
@@ -258,8 +273,11 @@ struct net_device {
 	 *
 	 * This is an address which is an intrinsic property of the
 	 * hardware, e.g. an address held in EEPROM.
+	 *
+	 * Note that the hardware address may not be the same length
+	 * as the link-layer address.
 	 */
-	uint8_t hw_addr[MAX_LL_ADDR_LEN];
+	uint8_t hw_addr[MAX_HW_ADDR_LEN];
 	/** Link-layer address
 	 *
 	 * This is the current link-layer address assigned to the

src/interface/efi/efi_snp.c

@@ -119,10 +119,11 @@ static EFI_GUID efi_pci_io_protocol_guid
 static void efi_snp_set_mode ( struct efi_snp_device *snpdev ) {
 	struct net_device *netdev = snpdev->netdev;
 	EFI_SIMPLE_NETWORK_MODE *mode = &snpdev->mode;
-	unsigned int ll_addr_len = netdev->ll_protocol->ll_addr_len;
+	struct ll_protocol *ll_protocol = netdev->ll_protocol;
+	unsigned int ll_addr_len = ll_protocol->ll_addr_len;
 
 	mode->HwAddressSize = ll_addr_len;
-	mode->MediaHeaderSize = netdev->ll_protocol->ll_header_len;
+	mode->MediaHeaderSize = ll_protocol->ll_header_len;
 	mode->MaxPacketSize = netdev->max_pkt_len;
 	mode->ReceiveFilterMask = ( EFI_SIMPLE_NETWORK_RECEIVE_UNICAST |
 				    EFI_SIMPLE_NETWORK_RECEIVE_MULTICAST |
@@ -130,8 +131,8 @@ static void efi_snp_set_mode ( struct efi_snp_device *snpdev ) {
 	assert ( ll_addr_len <= sizeof ( mode->CurrentAddress ) );
 	memcpy ( &mode->CurrentAddress, netdev->ll_addr, ll_addr_len );
 	memcpy ( &mode->BroadcastAddress, netdev->ll_broadcast, ll_addr_len );
-	memcpy ( &mode->PermanentAddress, netdev->hw_addr, ll_addr_len );
+	ll_protocol->init_addr ( netdev->hw_addr, &mode->PermanentAddress );
-	mode->IfType = ntohs ( netdev->ll_protocol->ll_proto );
+	mode->IfType = ntohs ( ll_protocol->ll_proto );
 	mode->MacAddressChangeable = TRUE;
 	mode->MediaPresentSupported = TRUE;
 	mode->MediaPresent = ( netdev_link_ok ( netdev ) ? TRUE : FALSE );

src/net/80211/net80211.c

@@ -602,9 +602,11 @@ static struct ll_protocol net80211_ll_protocol __ll_protocol = {
 	.name = "802.11",
 	.push = net80211_ll_push,
 	.pull = net80211_ll_pull,
+	.init_addr = eth_init_addr,
 	.ntoa = eth_ntoa,
 	.mc_hash = net80211_ll_mc_hash,
 	.ll_proto = htons ( ARPHRD_ETHER ),	/* "encapsulated Ethernet" */
+	.hw_addr_len = ETH_ALEN,
 	.ll_addr_len = ETH_ALEN,
 	.ll_header_len = IEEE80211_TYP_FRAME_HEADER_LEN +
 				IEEE80211_LLC_HEADER_LEN,

src/net/ethernet.c

@@ -96,6 +96,16 @@ static int eth_pull ( struct net_device *netdev __unused,
 	return 0;
 }
 
+/**
+ * Initialise Ethernet address
+ *
+ * @v hw_addr		Hardware address
+ * @v ll_addr		Link-layer address
+ */
+void eth_init_addr ( const void *hw_addr, void *ll_addr ) {
+	memcpy ( ll_addr, hw_addr, ETH_ALEN );
+}
+
 /**
  * Transcribe Ethernet address
  *
@@ -143,10 +153,12 @@ static int eth_mc_hash ( unsigned int af, const void *net_addr,
 struct ll_protocol ethernet_protocol __ll_protocol = {
 	.name		= "Ethernet",
 	.ll_proto	= htons ( ARPHRD_ETHER ),
+	.hw_addr_len	= ETH_ALEN,
 	.ll_addr_len	= ETH_ALEN,
 	.ll_header_len	= ETH_HLEN,
 	.push		= eth_push,
 	.pull		= eth_pull,
+	.init_addr	= eth_init_addr,
 	.ntoa		= eth_ntoa,
 	.mc_hash	= eth_mc_hash,
 };

src/net/netdevice.c

@@ -358,8 +358,7 @@ int register_netdev ( struct net_device *netdev ) {
 		   ifindex++ );
 
 	/* Set initial link-layer address */
-	memcpy ( netdev->ll_addr, netdev->hw_addr,
+	netdev->ll_protocol->init_addr ( netdev->hw_addr, netdev->ll_addr );
-		 netdev->ll_protocol->ll_addr_len );
 
 	/* Register per-netdev configuration settings */
 	if ( ( rc = register_settings ( netdev_settings ( netdev ),