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[sdi] Add support for SDI images
Add support (disabled by default) for booting .sdi images as used by Windows XP Embedded. Signed-off-by: Michael Brown <mcb30@ipxe.org>
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‎src/arch/i386/image/sdi.c

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/*
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* Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of the
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* License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301, USA.
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*/
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FILE_LICENCE ( GPL2_OR_LATER );
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#include <stdint.h>
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#include <string.h>
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#include <errno.h>
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#include <realmode.h>
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#include <sdi.h>
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#include <ipxe/image.h>
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#include <ipxe/features.h>
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/** @file
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*
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* System Deployment Image (SDI)
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*
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* Based on the MSDN article "RAM boot using SDI in Windows XP
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* Embedded with Service Pack 1", available at the time of writing
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* from:
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*
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* http://msdn.microsoft.com/en-us/library/ms838543.aspx
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*/
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FEATURE ( FEATURE_IMAGE, "SDI", DHCP_EB_FEATURE_SDI, 1 );
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/**
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* Parse SDI image header
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*
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* @v image SDI file
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* @v sdi SDI header to fill in
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* @ret rc Return status code
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*/
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static int sdi_parse_header ( struct image *image, struct sdi_header *sdi ) {
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/* Sanity check */
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if ( image->len < sizeof ( *sdi ) ) {
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DBGC ( image, "SDI %p too short for SDI header\n", image );
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return -ENOEXEC;
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}
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/* Read in header */
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copy_from_user ( sdi, image->data, 0, sizeof ( *sdi ) );
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/* Check signature */
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if ( sdi->magic != SDI_MAGIC ) {
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DBGC ( image, "SDI %p is not an SDI image\n", image );
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return -ENOEXEC;
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}
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return 0;
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}
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/**
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* Execute SDI image
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*
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* @v image SDI file
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* @ret rc Return status code
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*/
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static int sdi_exec ( struct image *image ) {
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struct sdi_header sdi;
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uint32_t sdiptr;
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int rc;
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/* Parse image header */
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if ( ( rc = sdi_parse_header ( image, &sdi ) ) != 0 )
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return rc;
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/* Check that image is bootable */
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if ( sdi.boot_size == 0 ) {
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DBGC ( image, "SDI %p is not bootable\n", image );
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return -ENOTTY;
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}
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DBGC ( image, "SDI %p image at %08lx+%08zx\n",
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image, user_to_phys ( image->data, 0 ), image->len );
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DBGC ( image, "SDI %p boot code at %08lx+%llx\n", image,
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user_to_phys ( image->data, sdi.boot_offset ), sdi.boot_size );
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/* Copy boot code */
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memcpy_user ( real_to_user ( SDI_BOOT_SEG, SDI_BOOT_OFF ), 0,
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image->data, sdi.boot_offset, sdi.boot_size );
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/* Jump to boot code */
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sdiptr = ( user_to_phys ( image->data, 0 ) | SDI_WTF );
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__asm__ __volatile__ ( REAL_CODE ( "ljmp %0, %1\n\t" )
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: : "i" ( SDI_BOOT_SEG ),
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"i" ( SDI_BOOT_OFF ),
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"d" ( sdiptr ) );
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/* There is no way for the image to return, since we provide
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* no return address.
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*/
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assert ( 0 );
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return -ECANCELED; /* -EIMPOSSIBLE */
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}
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/**
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* Probe SDI image
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*
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* @v image SDI file
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* @ret rc Return status code
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*/
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static int sdi_probe ( struct image *image ) {
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struct sdi_header sdi;
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int rc;
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/* Parse image */
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if ( ( rc = sdi_parse_header ( image, &sdi ) ) != 0 )
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return rc;
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return 0;
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}
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/** SDI image type */
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struct image_type sdi_image_type __image_type ( PROBE_NORMAL ) = {
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.name = "SDI",
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.probe = sdi_probe,
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.exec = sdi_exec,
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};

‎src/arch/i386/include/sdi.h

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#ifndef _SDI_H
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#define _SDI_H
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/** @file
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*
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* System Deployment Image (SDI)
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*
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*/
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FILE_LICENCE ( GPL2_OR_LATER );
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/** SDI image header */
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struct sdi_header {
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/** Signature */
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uint32_t magic;
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/** Version (as an ASCII string) */
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uint32_t version;
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/** Reserved */
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uint8_t reserved[8];
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/** Boot code offset */
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uint64_t boot_offset;
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/** Boot code size */
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uint64_t boot_size;
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} __attribute__ (( packed ));
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/** SDI image signature */
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#define SDI_MAGIC \
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( ( '$' << 0 ) | ( 'S' << 8 ) | ( 'D' << 16 ) | ( 'I' << 24 ) )
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/** SDI boot segment */
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#define SDI_BOOT_SEG 0x0000
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/** SDI boot offset */
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#define SDI_BOOT_OFF 0x7c00
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/** Constant to binary-OR with physical address of SDI image */
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#define SDI_WTF 0x41
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#endif /* _SDI_H */

‎src/arch/x86/include/bits/errfile.h

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@@ -31,6 +31,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
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#define ERRFILE_com32 ( ERRFILE_ARCH | ERRFILE_IMAGE | 0x00080000 )
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#define ERRFILE_comboot_resolv ( ERRFILE_ARCH | ERRFILE_IMAGE | 0x00090000 )
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#define ERRFILE_comboot_call ( ERRFILE_ARCH | ERRFILE_IMAGE | 0x000a0000 )
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#define ERRFILE_sdi ( ERRFILE_ARCH | ERRFILE_IMAGE | 0x000b0000 )
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#define ERRFILE_undi ( ERRFILE_ARCH | ERRFILE_NET | 0x00000000 )
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#define ERRFILE_undiload ( ERRFILE_ARCH | ERRFILE_NET | 0x00010000 )

‎src/config/config.c

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@@ -181,6 +181,9 @@ REQUIRE_OBJECT ( comboot_resolv );
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#ifdef IMAGE_EFI
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REQUIRE_OBJECT ( efi_image );
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#endif
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#ifdef IMAGE_SDI
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REQUIRE_OBJECT ( sdi );
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#endif
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/*
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* Drag in all requested commands

‎src/config/general.h

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//#define IMAGE_BZIMAGE /* Linux bzImage image support */
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//#define IMAGE_COMBOOT /* SYSLINUX COMBOOT image support */
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//#define IMAGE_EFI /* EFI image support */
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//#define IMAGE_SDI /* SDI image support */
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/*
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* Command-line commands to include

‎src/include/ipxe/features.h

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#define DHCP_EB_FEATURE_FCOE 0x25 /**< FCoE protocol */
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#define DHCP_EB_FEATURE_VLAN 0x26 /**< VLAN support */
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#define DHCP_EB_FEATURE_MENU 0x27 /**< Menu support */
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#define DHCP_EB_FEATURE_SDI 0x28 /**< SDI image support */
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/** @} */
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