Intel Extensible Firmware Interface, Specification

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Extensible Firmware Interface Specification
448 12/12/00 Version 1.02
G.4.14 MCast IP To MAC
Translate a multicast IPv4 or IPv6 address to a multicast MAC address.
G.4.14.1 Issuing the Command
To issue a MCast IP To MAC command, create a CDB and fill it in as shows in the table below:
CDB Field How to initialize the CDB structure for a MCast IP To MAC command
OpCode PXE_OPCODE_MCAST_IP_TO_MAC
OpFlags Set as needed.
CPBsize sizeof(PXE_CPB_MCAST_IP_TO_MAC)
DBsize
sizeof(PXE_DB_MCAST_IP_TO_MAC)
CPBaddr
Address of
PXE_CPB_MCAST_IP_TO_MAC
structure.
Dbaddr
Address of
PXE_DB_MCAST_IP_TO_MAC
structure.
StatCode PXE_STATCODE_INITIALIZE
StatFlags PXE_STATFLAGS_INITIALIZE
Ifnum
A valid interface number from zero to
!PXE.IFcnt
.
Control Set as needed.
OpFlags
To convert a multicast IP address to a multicast MAC address the UNDI needs to know the format
of the IP address. Set one of these OpFlags to identify the format of the IP addresses in the CPB:
•
PXE_OPFLAGS_MCAST_IPV4_TO_MAC
•
PXE_OPFLAGS_MCAST_IPV6_TO_MAC
Preparing the CPB
Fill in an array of one or more multicast IP addresses. Be sure to set the
CDB.CPBsize
and
CDB.CPBaddr
fields accordingly.
typedef struct s_pxe_cpb_mcast_ip_to_mac {
// Multicast IP address to be converted to multicast MAC address.
PXE_IP_ADDR IP[n];
} PXE_CPB_MCAST_IP_TO_MAC;