[efi] Expose DHCP packets via the Apple NetBoot protocol

Mac OS X uses non-standard EFI protocols to obtain the DHCP packets
from the UEFI firmware.

Originally-implemented-by: Michael Kuron <m.kuron@gmx.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/include/ipxe/efi/Protocol/AppleNetBoot.h

+#ifndef __EFI_APPLE_NET_BOOT_PROTOCOL_H__
+#define __EFI_APPLE_NET_BOOT_PROTOCOL_H__
+
+/** @file
+ *
+ * Apple Net Boot Protocol
+ *
+ */
+
+FILE_LICENCE ( BSD3 );
+
+#define EFI_APPLE_NET_BOOT_PROTOCOL_GUID				\
+	{ 0x78ee99fb, 0x6a5e, 0x4186,					\
+	{ 0x97, 0xde, 0xcd, 0x0a, 0xba, 0x34, 0x5a, 0x74 } }
+
+typedef struct _EFI_APPLE_NET_BOOT_PROTOCOL EFI_APPLE_NET_BOOT_PROTOCOL;
+
+/**
+  Get a DHCP packet obtained by the firmware during NetBoot.
+
+  @param  This		A pointer to the APPLE_NET_BOOT_PROTOCOL instance.
+  @param  BufferSize	A pointer to the size of the buffer in bytes.
+  @param  DataBuffer	The memory buffer to copy the packet to. If it is
+			NULL, then the size of the packet is returned
+			in BufferSize.
+  @retval EFI_SUCCESS		The packet was copied.
+  @retval EFI_BUFFER_TOO_SMALL	The BufferSize is too small to read the
+				current packet. BufferSize has been
+				updated with the size needed to
+				complete the request.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *GET_DHCP_RESPONSE) (
+  IN EFI_APPLE_NET_BOOT_PROTOCOL	*This,
+  IN OUT UINTN				*BufferSize,
+  OUT VOID				*DataBuffer
+  );
+
+struct _EFI_APPLE_NET_BOOT_PROTOCOL
+{
+  GET_DHCP_RESPONSE	GetDhcpResponse;
+  GET_DHCP_RESPONSE	GetBsdpResponse;
+};
+
+#endif /*__EFI_APPLE_NET_BOOT_PROTOCOL_H__ */

src/include/ipxe/efi/efi.h

 #define EEFI( efirc ) EPLATFORM ( EINFO_EPLATFORM, efirc )
 
 extern EFI_GUID efi_absolute_pointer_protocol_guid;
+extern EFI_GUID efi_apple_net_boot_protocol_guid;
 extern EFI_GUID efi_arp_protocol_guid;
 extern EFI_GUID efi_arp_service_binding_protocol_guid;
 extern EFI_GUID efi_block_io_protocol_guid;

src/interface/efi/efi_debug.c

 static struct efi_well_known_guid efi_well_known_guids[] = {
 	{ &efi_absolute_pointer_protocol_guid,
 	  "AbsolutePointer" },
+	{ &efi_apple_net_boot_protocol_guid,
+	  "AppleNetBoot" },
 	{ &efi_arp_protocol_guid,
 	  "Arp" },
 	{ &efi_arp_service_binding_protocol_guid,

src/interface/efi/efi_guid.c

 
 #include <ipxe/efi/efi.h>
 #include <ipxe/efi/Protocol/AbsolutePointer.h>
+#include <ipxe/efi/Protocol/AppleNetBoot.h>
 #include <ipxe/efi/Protocol/Arp.h>
 #include <ipxe/efi/Protocol/BlockIo.h>
 #include <ipxe/efi/Protocol/BusSpecificDriverOverride.h>
 EFI_GUID efi_absolute_pointer_protocol_guid
 	= EFI_ABSOLUTE_POINTER_PROTOCOL_GUID;
 
+/** Apple NetBoot protocol GUID */
+EFI_GUID efi_apple_net_boot_protocol_guid
+	= EFI_APPLE_NET_BOOT_PROTOCOL_GUID;
+
 /** ARP protocol GUID */
 EFI_GUID efi_arp_protocol_guid
 	= EFI_ARP_PROTOCOL_GUID;

src/interface/efi/efi_pxe.c

 #include <ipxe/efi/efi_snp.h>
 #include <ipxe/efi/efi_pxe.h>
 #include <ipxe/efi/Protocol/PxeBaseCode.h>
+#include <ipxe/efi/Protocol/AppleNetBoot.h>
 #include <usr/ifmgmt.h>
 #include <config/general.h>
 
 	EFI_PXE_BASE_CODE_PROTOCOL base;
 	/** PXE base code mode */
 	EFI_PXE_BASE_CODE_MODE mode;
+	/** Apple NetBoot protocol */
+	EFI_APPLE_NET_BOOT_PROTOCOL apple;
 
 	/** TCP/IP network-layer protocol */
 	struct tcpip_net_protocol *tcpip;
 	.SetPackets	= efi_pxe_set_packets,
 };
 
+/******************************************************************************
+ *
+ * Apple NetBoot protocol
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Get DHCP/BSDP response
+ *
+ * @v packet		Packet
+ * @v len		Length of data buffer
+ * @v data		Data buffer
+ * @ret efirc		EFI status code
+ */
+static EFI_STATUS EFIAPI
+efi_apple_get_response ( EFI_PXE_BASE_CODE_PACKET *packet, UINTN *len,
+			 VOID *data ) {
+
+	/* Check length */
+	if ( *len < sizeof ( *packet ) ) {
+		*len = sizeof ( *packet );
+		return EFI_BUFFER_TOO_SMALL;
+	}
+
+	/* Copy packet */
+	memcpy ( data, packet, sizeof ( *packet ) );
+	*len = sizeof ( *packet );
+
+	return EFI_SUCCESS;
+}
+
+/**
+ * Get DHCP response
+ *
+ * @v apple		Apple NetBoot protocol
+ * @v len		Length of data buffer
+ * @v data		Data buffer
+ * @ret efirc		EFI status code
+ */
+static EFI_STATUS EFIAPI
+efi_apple_get_dhcp_response ( EFI_APPLE_NET_BOOT_PROTOCOL *apple,
+			      UINTN *len, VOID *data ) {
+	struct efi_pxe *pxe = container_of ( apple, struct efi_pxe, apple );
+
+	return efi_apple_get_response ( &pxe->mode.DhcpAck, len, data );
+}
+
+/**
+ * Get BSDP response
+ *
+ * @v apple		Apple NetBoot protocol
+ * @v len		Length of data buffer
+ * @v data		Data buffer
+ * @ret efirc		EFI status code
+ */
+static EFI_STATUS EFIAPI
+efi_apple_get_bsdp_response ( EFI_APPLE_NET_BOOT_PROTOCOL *apple,
+			      UINTN *len, VOID *data ) {
+	struct efi_pxe *pxe = container_of ( apple, struct efi_pxe, apple );
+
+	return efi_apple_get_response ( &pxe->mode.PxeReply, len, data );
+}
+
+/** Apple NetBoot protocol */
+static EFI_APPLE_NET_BOOT_PROTOCOL efi_apple_net_boot_protocol = {
+	.GetDhcpResponse = efi_apple_get_dhcp_response,
+	.GetBsdpResponse = efi_apple_get_bsdp_response,
+};
+
+/******************************************************************************
+ *
+ * Installer
+ *
+ ******************************************************************************
+ */
+
 /**
  * Install PXE base code protocol
  *
 	pxe->handle = handle;
 	memcpy ( &pxe->base, &efi_pxe_base_code_protocol, sizeof ( pxe->base ));
 	pxe->base.Mode = &pxe->mode;
+	memcpy ( &pxe->apple, &efi_apple_net_boot_protocol,
+		 sizeof ( pxe->apple ) );
 	pxe->buf.op = &efi_pxe_buf_operations;
 	intf_init ( &pxe->tftp, &efi_pxe_tftp_desc, &pxe->refcnt );
 	intf_init ( &pxe->udp, &efi_pxe_udp_desc, &pxe->refcnt );
 
 	/* Install PXE base code protocol */
 	if ( ( efirc = bs->InstallMultipleProtocolInterfaces (
-			&handle, &efi_pxe_base_code_protocol_guid, &pxe->base,
+			&handle,
+			&efi_pxe_base_code_protocol_guid, &pxe->base,
+			&efi_apple_net_boot_protocol_guid, &pxe->apple,
 			NULL ) ) != 0 ) {
 		rc = -EEFI ( efirc );
 		DBGC ( pxe, "PXE %s could not install base code protocol: %s\n",
 	return 0;
 
 	bs->UninstallMultipleProtocolInterfaces (
-			handle, &efi_pxe_base_code_protocol_guid, &pxe->base,
+			handle,
+			&efi_pxe_base_code_protocol_guid, &pxe->base,
+			&efi_apple_net_boot_protocol_guid, &pxe->apple,
 			NULL );
  err_install_protocol:
 	ref_put ( &pxe->refcnt );
 
 	/* Uninstall PXE base code protocol */
 	bs->UninstallMultipleProtocolInterfaces (
-			handle, &efi_pxe_base_code_protocol_guid, &pxe->base,
+			handle,
+			&efi_pxe_base_code_protocol_guid, &pxe->base,
+			&efi_apple_net_boot_protocol_guid, &pxe->apple,
 			NULL );
 
 	/* Remove from list and drop list's reference */