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/* ----------------------------------------------------------------------- *
*
* Copyright 2007-2008 H. Peter Anvin - All Rights Reserved
* Copyright 2009-2011 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
* the Free Software Foundation, Inc., 53 Temple Place Ste 330,
* Boston MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
#ifndef SYSLXINT_H
#define SYSLXINT_H
#include "syslinux.h"
#if defined(__386__) || defined(__i386__) || defined(__x86_64__)
# define X86_MEM 1 /* Littleendian and unaligned safe */
#else
# define X86_MEM 0
#endif
/*
* Access functions for littleendian numbers, possibly misaligned.
*/
static inline uint8_t get_8(const uint8_t * p)
{
return *p;
}
static inline uint16_t get_16(const uint16_t * p)
{
#if X86_MEM
/* Littleendian and unaligned-capable */
return *p;
#else
const uint8_t *pp = (const uint8_t *)p;
return pp[0] + ((uint16_t)pp[1] << 8);
#endif
}
static inline uint32_t get_32(const uint32_t * p)
{
#if X86_MEM
/* Littleendian and unaligned-capable */
return *p;
#else
const uint16_t *pp = (const uint16_t *)p;
return get_16(pp[0]) + (uint32_t)get_16(pp[1]);
#endif
}
static inline uint64_t get_64(const uint64_t * p)
{
#if X86_MEM
/* Littleendian and unaligned-capable */
return *p;
#else
const uint32_t *pp = (const uint32_t *)p;
return get_32(pp[0]) + (uint64_t)get_32(pp[1]);
#endif
}
static inline void set_8(uint8_t *p, uint8_t v)
{
*p = v;
}
static inline void set_16(uint16_t *p, uint16_t v)
{
#if X86_MEM
/* Littleendian and unaligned-capable */
*p = v;
#else
uint8_t *pp = (uint8_t *) p;
pp[0] = (v & 0xff);
pp[1] = ((v >> 8) & 0xff);
#endif
}
static inline void set_32(uint32_t *p, uint32_t v)
{
#if X86_MEM
/* Littleendian and unaligned-capable */
*p = v;
#else
uint8_t *pp = (uint8_t *) p;
pp[0] = (v & 0xff);
pp[1] = ((v >> 8) & 0xff);
pp[2] = ((v >> 16) & 0xff);
pp[3] = ((v >> 24) & 0xff);
#endif
}
static inline void set_64(uint64_t *p, uint64_t v)
{
#if X86_MEM
/* Littleendian and unaligned-capable */
*p = v;
#else
uint32_t *pp = (uint32_t *) p;
set_32(pp[0], v);
set_32(pp[1], v >> 32);
#endif
}
/*
* Special handling for the MS-DOS derivative: syslinux_ldlinux
* is a "far" object...
*/
#ifdef __MSDOS__
static inline __attribute__ ((const))
uint16_t ds(void)
{
uint16_t v;
asm("movw %%ds,%0":"=rm"(v));
return v;
}
static inline void *set_fs(const void *p)
{
uint16_t seg;
seg = ds() + ((size_t) p >> 4);
asm volatile ("movw %0,%%fs"::"rm" (seg));
return (void *)((size_t) p & 0xf);
}
uint8_t get_8_sl(const uint8_t * p);
uint16_t get_16_sl(const uint16_t * p);
uint32_t get_32_sl(const uint32_t * p);
uint64_t get_64_sl(const uint64_t * p);
void set_8_sl(uint8_t * p, uint8_t v);
void set_16_sl(uint16_t * p, uint16_t v);
void set_32_sl(uint32_t * p, uint32_t v);
void set_64_sl(uint64_t * p, uint64_t v);
void memcpy_to_sl(void *dst, const void *src, size_t len);
void memcpy_from_sl(void *dst, const void *src, size_t len);
#else
/* Sane system ... */
#define get_8_sl(x) get_8(x)
#define get_16_sl(x) get_16(x)
#define get_32_sl(x) get_32(x)
#define get_64_sl(x) get_64(x)
#define set_8_sl(x,y) set_8(x,y)
#define set_16_sl(x,y) set_16(x,y)
#define set_32_sl(x,y) set_32(x,y)
#define set_64_sl(x,y) set_64(x,y)
#define memcpy_to_sl(d,s,l) memcpy(d,s,l)
#define memcpy_from_sl(d,s,l) memcpy(d,s,l)
#endif
#define LDLINUX_MAGIC 0x3eb202fe
#define BS_MAGIC_VER (0x1b << 9)
/* Patch area for disk-based installers */
struct patch_area {
uint32_t magic; /* LDLINUX_MAGIC */
uint32_t instance; /* Per-version value */
uint16_t data_sectors;
uint16_t adv_sectors;
uint32_t dwords;
uint32_t checksum;
uint16_t maxtransfer;
uint16_t epaoffset; /* Pointer to the extended patch area */
};
struct ext_patch_area {
uint16_t advptroffset; /* ADV pointers */
uint16_t diroffset; /* Current directory field */
uint16_t dirlen; /* Length of current directory field */
uint16_t subvoloffset; /* Subvolume field */
uint16_t subvollen; /* Length of subvolume field */
uint16_t secptroffset; /* Sector extent pointers */
uint16_t secptrcnt; /* Number of sector extent pointers */
uint16_t sect1ptr0; /* Boot sector offset of sector 1 ptr LSW */
uint16_t sect1ptr1; /* Boot sector offset of sector 1 ptr MSW */
uint16_t raidpatch; /* Boot sector RAID mode patch pointer */
};
/* Sector extent */
struct syslinux_extent {
uint64_t lba;
uint16_t len;
} __attribute__((packed));
/* FAT bootsector format, also used by other disk-based derivatives */
struct boot_sector {
uint8_t bsJump[3];
char bsOemName[8];
uint16_t bsBytesPerSec;
uint8_t bsSecPerClust;
uint16_t bsResSectors;
uint8_t bsFATs;
uint16_t bsRootDirEnts;
uint16_t bsSectors;
uint8_t bsMedia;
uint16_t bsFATsecs;
uint16_t bsSecPerTrack;
uint16_t bsHeads;
uint32_t bsHiddenSecs;
uint32_t bsHugeSectors;
union {
struct {
uint8_t DriveNumber;
uint8_t Reserved1;
uint8_t BootSignature;
uint32_t VolumeID;
char VolumeLabel[11];
char FileSysType[8];
uint8_t Code[442];
} __attribute__ ((packed)) bs16;
struct {
uint32_t FATSz32;
uint16_t ExtFlags;
uint16_t FSVer;
uint32_t RootClus;
uint16_t FSInfo;
uint16_t BkBootSec;
uint8_t Reserved0[12];
uint8_t DriveNumber;
uint8_t Reserved1;
uint8_t BootSignature;
uint32_t VolumeID;
char VolumeLabel[11];
char FileSysType[8];
uint8_t Code[414];
} __attribute__ ((packed)) bs32;
} __attribute__ ((packed));
uint32_t bsMagic;
uint16_t bsForwardPtr;
uint16_t bsSignature;
} __attribute__ ((packed));
#define bsHead bsJump
#define bsHeadLen offsetof(struct boot_sector, bsBytesPerSec)
#define bsCode bs32.Code /* The common safe choice */
#define bsCodeLen (offsetof(struct boot_sector, bsSignature) - \
offsetof(struct boot_sector, bsCode))
static inline int fat_check_sb_fields(const struct boot_sector *sb)
{
return sb->bsResSectors && sb->bsFATs &&
(!memcmp(sb->bs16.FileSysType, "FAT12 ", 8) ||
!memcmp(sb->bs16.FileSysType, "FAT16 ", 8) ||
!memcmp(sb->bs16.FileSysType, "FAT ", 8) ||
!memcmp(sb->bs32.FileSysType, "FAT32 ", 8));
}
#endif /* SYSLXINT_H */