diff options
Diffstat (limited to 'libinstaller/syslxmod.c')
| -rw-r--r-- | libinstaller/syslxmod.c | 203 |
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(§buf->bsMedia) != 0xF0 && + get_8(§buf->bsMedia) < 0xF8 ) goto invalid; - sectorsize = get_16(sectbuf+bsBytesPerSec); + sectorsize = get_16(§buf->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(§buf->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(§buf->bsSectors); + sectors = sectors ? sectors : get_32(§buf->bsHugeSectors); - dsectors = sectors - get_16(sectbuf+bsResSectors); + dsectors = sectors - get_16(§buf->bsResSectors); - fatsectors = get_16(sectbuf+bsFATsecs); - fatsectors = fatsectors ? fatsectors : get_32(sectbuf+bs32FATSz32); - fatsectors *= get_8(sectbuf+bsFATs); + fatsectors = get_16(§buf->bsFATsecs); + fatsectors = fatsectors ? fatsectors : get_32(§buf->bs32.FATSz32); + fatsectors *= get_8(§buf->bsFATs); dsectors -= fatsectors; - rootdirents = get_16(sectbuf+bsRootDirEnts); + rootdirents = get_16(§buf->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(§buf->bsFATsecs) ) goto invalid; - if ( get_8(sectbuf+bs16BootSignature) == 0x29 ) { - if ( !memcmp(sectbuf+bs16FileSysType, "FAT12 ", 8) ) { + if ( get_8(§buf->bs16.BootSignature) == 0x29 ) { + if ( !memcmp(§buf->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(§buf->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(§buf->bs16.FileSysType, "FAT ", 8) ) { static char fserr[] = "filesystem type \"????????\" not supported"; - memcpy(fserr+17, sectbuf+bs16FileSysType, 8); + memcpy(fserr+17, §buf->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(§buf->bs32.BootSignature) != 0x29 || + memcmp(§buf->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; } |