aboutsummaryrefslogtreecommitdiffstats
path: root/libinstaller/syslxmod.c
diff options
context:
space:
mode:
Diffstat (limited to 'libinstaller/syslxmod.c')
-rw-r--r--libinstaller/syslxmod.c203
1 files changed, 53 insertions, 150 deletions
diff --git a/libinstaller/syslxmod.c b/libinstaller/syslxmod.c
index fb2f1d7a..d1cc13bf 100644
--- a/libinstaller/syslxmod.c
+++ b/libinstaller/syslxmod.c
@@ -1,6 +1,7 @@
/* ----------------------------------------------------------------------- *
*
* Copyright 1998-2008 H. Peter Anvin - All Rights Reserved
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -22,117 +23,16 @@
#include <stddef.h>
#include "syslinux.h"
+#include "syslxint.h"
-#define LDLINUX_MAGIC 0x3eb202fe
-
-enum bs_offsets {
- bsJump = 0x00,
- bsOemName = 0x03,
- bsBytesPerSec = 0x0b,
- bsSecPerClust = 0x0d,
- bsResSectors = 0x0e,
- bsFATs = 0x10,
- bsRootDirEnts = 0x11,
- bsSectors = 0x13,
- bsMedia = 0x15,
- bsFATsecs = 0x16,
- bsSecPerTrack = 0x18,
- bsHeads = 0x1a,
- bsHiddenSecs = 0x1c,
- bsHugeSectors = 0x20,
-
- /* FAT12/16 only */
- bs16DriveNumber = 0x24,
- bs16Reserved1 = 0x25,
- bs16BootSignature = 0x26,
- bs16VolumeID = 0x27,
- bs16VolumeLabel = 0x2b,
- bs16FileSysType = 0x36,
- bs16Code = 0x3e,
-
- /* FAT32 only */
- bs32FATSz32 = 36,
- bs32ExtFlags = 40,
- bs32FSVer = 42,
- bs32RootClus = 44,
- bs32FSInfo = 48,
- bs32BkBootSec = 50,
- bs32Reserved = 52,
- bs32DriveNumber = 64,
- bs32Reserved1 = 65,
- bs32BootSignature = 66,
- bs32VolumeID = 67,
- bs32VolumeLabel = 71,
- bs32FileSysType = 82,
- bs32Code = 90,
-
- bsSignature = 0x1fe
-};
-
-#define bsHead bsJump
-#define bsHeadLen (bsOemName-bsHead)
-#define bsCode bs32Code /* The common safe choice */
-#define bsCodeLen (bsSignature-bs32Code)
-
-/*
- * Access functions for littleendian numbers, possibly misaligned.
- */
-static inline uint8_t get_8(const unsigned char *p)
-{
- return *(const uint8_t *)p;
-}
-
-static inline uint16_t get_16(const unsigned char *p)
-{
-#if defined(__i386__) || defined(__x86_64__)
- /* Littleendian and unaligned-capable */
- return *(const uint16_t *)p;
-#else
- return (uint16_t)p[0] + ((uint16_t)p[1] << 8);
-#endif
-}
-
-static inline uint32_t get_32(const unsigned char *p)
-{
-#if defined(__i386__) || defined(__x86_64__)
- /* Littleendian and unaligned-capable */
- return *(const uint32_t *)p;
-#else
- return (uint32_t)p[0] + ((uint32_t)p[1] << 8) +
- ((uint32_t)p[2] << 16) + ((uint32_t)p[3] << 24);
-#endif
-}
-
-static inline void set_16(unsigned char *p, uint16_t v)
-{
-#if defined(__i386__) || defined(__x86_64__)
- /* Littleendian and unaligned-capable */
- *(uint16_t *)p = v;
-#else
- p[0] = (v & 0xff);
- p[1] = ((v >> 8) & 0xff);
-#endif
-}
-
-static inline void set_32(unsigned char *p, uint32_t v)
-{
-#if defined(__i386__) || defined(__x86_64__)
- /* Littleendian and unaligned-capable */
- *(uint32_t *)p = v;
-#else
- p[0] = (v & 0xff);
- p[1] = ((v >> 8) & 0xff);
- p[2] = ((v >> 16) & 0xff);
- p[3] = ((v >> 24) & 0xff);
-#endif
-}
+#define sbs ((struct boot_sector *)syslinux_bootsect)
void syslinux_make_bootsect(void *bs)
{
- unsigned char *bootsect = bs;
+ struct boot_sector *bootsect = bs;
- memcpy(bootsect+bsHead, syslinux_bootsect+bsHead, bsHeadLen);
- memcpy(bootsect+bsCode, syslinux_bootsect+bsCode, bsCodeLen);
+ memcpy(&bootsect->bsHead, &sbs->bsHead, bsHeadLen);
+ memcpy(&bootsect->bsCode, &sbs->bsCode, bsCodeLen);
}
/*
@@ -146,16 +46,16 @@ const char *syslinux_check_bootsect(const void *bs)
long long sectors, fatsectors, dsectors;
long long clusters;
int rootdirents, clustersize;
- const unsigned char *sectbuf = bs;
+ const struct boot_sector *sectbuf = bs;
veryold = 0;
/* Must be 0xF0 or 0xF8..0xFF */
- if ( get_8(sectbuf+bsMedia) != 0xF0 &&
- get_8(sectbuf+bsMedia) < 0xF8 )
+ if ( get_8(&sectbuf->bsMedia) != 0xF0 &&
+ get_8(&sectbuf->bsMedia) < 0xF8 )
goto invalid;
- sectorsize = get_16(sectbuf+bsBytesPerSec);
+ sectorsize = get_16(&sectbuf->bsBytesPerSec);
if ( sectorsize == 512 )
; /* ok */
else if ( sectorsize == 1024 || sectorsize == 2048 || sectorsize == 4096 )
@@ -163,21 +63,21 @@ const char *syslinux_check_bootsect(const void *bs)
else
goto invalid;
- clustersize = get_8(sectbuf+bsSecPerClust);
+ clustersize = get_8(&sectbuf->bsSecPerClust);
if ( clustersize == 0 || (clustersize & (clustersize-1)) )
goto invalid; /* Must be nonzero and a power of 2 */
- sectors = get_16(sectbuf+bsSectors);
- sectors = sectors ? sectors : get_32(sectbuf+bsHugeSectors);
+ sectors = get_16(&sectbuf->bsSectors);
+ sectors = sectors ? sectors : get_32(&sectbuf->bsHugeSectors);
- dsectors = sectors - get_16(sectbuf+bsResSectors);
+ dsectors = sectors - get_16(&sectbuf->bsResSectors);
- fatsectors = get_16(sectbuf+bsFATsecs);
- fatsectors = fatsectors ? fatsectors : get_32(sectbuf+bs32FATSz32);
- fatsectors *= get_8(sectbuf+bsFATs);
+ fatsectors = get_16(&sectbuf->bsFATsecs);
+ fatsectors = fatsectors ? fatsectors : get_32(&sectbuf->bs32.FATSz32);
+ fatsectors *= get_8(&sectbuf->bsFATs);
dsectors -= fatsectors;
- rootdirents = get_16(sectbuf+bsRootDirEnts);
+ rootdirents = get_16(&sectbuf->bsRootDirEnts);
dsectors -= (rootdirents+sectorsize/32-1)/sectorsize;
if ( dsectors < 0 || fatsectors == 0 )
@@ -188,27 +88,27 @@ const char *syslinux_check_bootsect(const void *bs)
if ( clusters < 0xFFF5 ) {
/* FAT12 or FAT16 */
- if ( !get_16(sectbuf+bsFATsecs) )
+ if ( !get_16(&sectbuf->bsFATsecs) )
goto invalid;
- if ( get_8(sectbuf+bs16BootSignature) == 0x29 ) {
- if ( !memcmp(sectbuf+bs16FileSysType, "FAT12 ", 8) ) {
+ if ( get_8(&sectbuf->bs16.BootSignature) == 0x29 ) {
+ if ( !memcmp(&sectbuf->bs16.FileSysType, "FAT12 ", 8) ) {
if ( clusters >= 0xFF5 )
return "more than 4084 clusters but claims FAT12";
- } else if ( !memcmp(sectbuf+bs16FileSysType, "FAT16 ", 8) ) {
+ } else if ( !memcmp(&sectbuf->bs16.FileSysType, "FAT16 ", 8) ) {
if ( clusters < 0xFF5 )
return "less than 4084 clusters but claims FAT16";
- } else if ( memcmp(sectbuf+bs16FileSysType, "FAT ", 8) ) {
+ } else if ( memcmp(&sectbuf->bs16.FileSysType, "FAT ", 8) ) {
static char fserr[] = "filesystem type \"????????\" not supported";
- memcpy(fserr+17, sectbuf+bs16FileSysType, 8);
+ memcpy(fserr+17, &sectbuf->bs16.FileSysType, 8);
return fserr;
}
}
} else if ( clusters < 0x0FFFFFF5 ) {
/* FAT32 */
/* Moving the FileSysType and BootSignature was a lovely stroke of M$ idiocy */
- if ( get_8(sectbuf+bs32BootSignature) != 0x29 ||
- memcmp(sectbuf+bs32FileSysType, "FAT32 ", 8) )
+ if ( get_8(&sectbuf->bs32.BootSignature) != 0x29 ||
+ memcmp(&sectbuf->bs32.FileSysType, "FAT32 ", 8) )
goto invalid;
} else {
goto invalid;
@@ -221,7 +121,7 @@ const char *syslinux_check_bootsect(const void *bs)
}
/*
- * This patches the boot sector and the first sector of ldlinux.sys
+ * This patches the boot sector and the beginning of ldlinux.sys
* based on an ldlinux.sys sector map passed in. Typically this is
* handled by writing ldlinux.sys, mapping it, and then overwrite it
* with the patched version. If this isn't safe to do because of
@@ -233,10 +133,11 @@ const char *syslinux_check_bootsect(const void *bs)
int syslinux_patch(const uint32_t *sectors, int nsectors,
int stupid, int raid_mode)
{
- unsigned char *patcharea, *p;
+ struct patch_area *patcharea;
+ uint32_t *wp;
int nsect = (syslinux_ldlinux_len+511) >> 9;
uint32_t csum;
- int i, dw;
+ int i, dw, nptrs;
if ( nsectors < nsect )
return -1;
@@ -244,44 +145,46 @@ int syslinux_patch(const uint32_t *sectors, int nsectors,
/* Patch in options, as appropriate */
if (stupid) {
/* Access only one sector at a time */
- set_16(syslinux_bootsect+0x1FC, 1);
+ set_16(&sbs->MaxTransfer, 1);
}
- i = get_16(syslinux_bootsect+0x1FE);
+ i = get_16(&sbs->bsSignature);
if (raid_mode)
- set_16(syslinux_bootsect+i, 0x18CD); /* INT 18h */
- set_16(syslinux_bootsect+0x1FE, 0xAA55);
+ set_16((uint16_t *)((char *)sbs+i), 0x18CD); /* INT 18h */
+ set_16(&sbs->bsSignature, 0xAA55);
/* First sector need pointer in boot sector */
- set_32(syslinux_bootsect+0x1F8, *sectors++);
+ set_32(&sbs->NextSector, *sectors++);
nsect--;
/* Search for LDLINUX_MAGIC to find the patch area */
- for ( p = syslinux_ldlinux ; get_32(p) != LDLINUX_MAGIC ; p += 4 );
- patcharea = p+8;
+ for (wp = (uint32_t *)syslinux_ldlinux; get_32(wp) != LDLINUX_MAGIC; wp++)
+ ;
+ patcharea = (struct patch_area *)wp;
/* Set up the totals */
- dw = syslinux_ldlinux_len >> 2; /* COMPLETE dwords! */
- set_16(patcharea, dw);
- set_16(patcharea+2, nsect); /* Does not include the first sector! */
+ dw = syslinux_ldlinux_len >> 2; /* COMPLETE dwords, excluding ADV */
+ set_16(&patcharea->data_sectors, nsect); /* Not including ADVs */
+ set_16(&patcharea->adv_sectors, 0); /* ADVs not supported yet */
+ set_32(&patcharea->dwords, dw);
+ set_32(&patcharea->currentdir, 0);
/* Set the sector pointers */
- p = patcharea+8;
+ wp = (uint32_t *)((char *)syslinux_ldlinux+get_16(&patcharea->secptroffset));
+ nptrs = get_16(&patcharea->secptrcnt);
- memset(p, 0, 64*4);
- while ( nsect-- ) {
- set_32(p, *sectors++);
- p += 4;
- }
+ memset(wp, 0, nptrs*4);
+ while ( nsect-- )
+ set_32(wp++, *sectors++);
/* Now produce a checksum */
- set_32(patcharea+4, 0);
+ set_32(&patcharea->checksum, 0);
csum = LDLINUX_MAGIC;
- for ( i = 0, p = syslinux_ldlinux ; i < dw ; i++, p += 4 )
- csum -= get_32(p); /* Negative checksum */
+ for (i = 0, wp = (uint32_t *)syslinux_ldlinux; i < dw; i++, wp++)
+ csum -= get_32(wp); /* Negative checksum */
- set_32(patcharea+4, csum);
+ set_32(&patcharea->checksum, csum);
- return 0;
+ return 0;
}