fsys_ntfs.c.org

grub4dos-0.4.4-2008- 08-src.zip

/* vim: set sw=4 :*/
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 1999  Free Software Foundation, Inc.
 *
 *  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; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 * Samuel Leo <samuel@_.remove.me._szonline.net>
 * Limitations:
 * 1. Only 32 bit size support
 * 2. don't support >1k MFT record size, >16k INDEX record size
 * 3. don't support recursive at_attribute_list
 * 4. don't support compressed attribute other than Datastream
 * 5. all MFT's at_attribute_list must resident at first run list
 * 6. don't support journaling
 * 7. don't support EFS encryption
 * 8. don't support mount point and junction
 */
#ifdef FSYS_NTFS

//#define DEBUG_NTFS 1

/*
#define NO_ATTRIBUTE_LIST 1
   totally disable at_attribute_list support,
   if no compressed/fragment file and MFT,
   not recommended
#define NO_NON_RESIDENT_ATTRIBUTE_LIST 1
   disable non-resident at_attribute_list support,
   if no huge compressed/fragment file and MFT
#define NO_NTFS_DECOMPRESSION 1
   disable ntfs compressed file support
#define NO_ALTERNATE_DATASTREAM 1
   disable ntfs alternate datastream support
*/
/*#ifdef STAGE1_5*/

#include <shared.h>
#include <filesys.h>
#include "ntfs.h"

/* safe turn off non-resident attribute list if MFT fragments < 4000 */
//#define NO_NON_RESIDENT_ATTRIBUTE_LIST 1
#define NO_NTFS_DECOMPRESSION 1
#endif


#define MAX_MFT_RECORD_SIZE 1024
#define MAX_INDEX_RECORD_SIZE 16384
#define MAX_INDEX_BITMAP_SIZE 4096
#define DECOMP_DEST_BUFFER_SIZE 16384
#define DECOMP_SOURCE_BUFFER_SIZE (8192+2)
#define MAX_DIR_DEPTH 64

/* sizes are always in bytes, BLOCK values are always in DEV_BSIZE (sectors) */
#define DEV_BSIZE 512

/* include/linux/fs.h */
#define BLOCK_SIZE 	512

#define WHICH_SUPER 1
#define SBLOCK (WHICH_SUPER * BLOCK_SIZE / DEV_BSIZE)	/* = 2 */

/* include/asm-i386/type.h */
//typedef __signed__ char __s8;
//typedef unsigned char __u8;
//typedef __signed__ short __s16;
//typedef unsigned short __u16;
//typedef __signed__ int __s32;
//typedef unsigned int __u32;
//typedef __signed__ long long __s64;
//typedef unsigned long long __u64;

#define FILE_MFT      0
#define FILE_MFTMIRR  1
#define FILE_LOGFILE  2
#define FILE_VOLUME   3
#define FILE_ATTRDEF  4
#define FILE_ROOT     5
#define FILE_BITMAP   6
#define FILE_BOOT     7
#define FILE_BADCLUS  8
#define FILE_QUOTA    9
#define FILE_UPCASE  10

#define at_standard_information 0x10
#define at_attribute_list 	0x20
#define at_filename		0x30
#define at_security_descriptor	0x50
#define at_data			0x80
#define at_index_root		0x90
#define at_index_allocation	0xa0
#define at_bitmap		0xb0
#define at_symlink		0xc0

#define NONAME	""
#define ATTR_NORMAL	0
#define ATTR_COMPRESSED	1
#define ATTR_RESIDENT	2
#define ATTR_ENCRYPTED	16384
#define ATTR_SPARSE	32768



#define index_data	((char *)FSYS_BUF)
#define bitmap_data	((unsigned char *)(FSYS_BUF+MAX_INDEX_RECORD_SIZE))
#define dcdbuf	((unsigned char *)index_data)
#define dcsbuf	(bitmap_data)
#define dcend	(dcsbuf+DECOMP_SOURCE_BUFFER_SIZE)
#define fnbuf ((char *)(bitmap_data+MAX_INDEX_BITMAP_SIZE))
#define mmft	((MFTR *)dcend)
#define cmft	((MFTR *)(dcend+sizeof(MFTR)))
#define mft_run	((RUNL *)(dcend+2*sizeof(MFTR)))
#define path_ino ((unsigned long *)(dcend+2*sizeof(MFTR)+sizeof(RUNL)))
#define cluster16 (path_ino+MAX_DIR_DEPTH)
#define index16 cluster16[16]
#define blocksize cluster16[17]
#define clustersize cluster16[18]
#define mft_record_size cluster16[19]
#define index_record_size cluster16[20]
#define dcvcn cluster16[21]
#define dcoff cluster16[22]
#define dclen cluster16[23]
#define dcrem cluster16[24]
#define dcslen cluster16[25]
#define dcsptr ((unsigned char *)cluster16[26])
#define is_ads_completion cluster16[27]

typedef struct run_list {
	char *start;
	char *ptr;
	unsigned long svcn;
	unsigned long evcn;
	unsigned long vcn;
	unsigned long cnum0;
	unsigned long cnum;
	unsigned long clen;
} RUNL;

typedef struct ntfs_mft_record {
	char mft[MAX_MFT_RECORD_SIZE];
	char mft2[MAX_MFT_RECORD_SIZE];
	unsigned long attr_type;
	char *attr_name;
	unsigned long attr_flag;
	unsigned long attr_size;
	char *attr;
	unsigned long attr_len;
	RUNL runl;
	char *attr_list;
	unsigned long attr_list_len;
	unsigned long attr_list_size;
	unsigned long attr_list_off;
	unsigned long attr_inited;
	char attr_list_buf[2*BLOCK_SIZE];
	RUNL attr_list_runl;
} MFTR;

static int read_mft_record(unsigned long mftno, char *mft, unsigned long self);
static unsigned long read_attribute(MFTR *mftr, unsigned long offset, char *buf, unsigned long len, RUNL *from_rl);
static int get_next_run(RUNL *runl);



#if 0
static inline int
nsubstring (char *s1, char *s2)
{
    while (tolower(*s1) == tolower(*s2))
    {
	/* The strings match exactly. */
	if (! *(s1++))
	    return 0;
	s2 ++;
    }

    /* S1 is a substring of S2. */
    if (*s1 == 0)
	return -1;

    /* S1 isn't a substring. */
    return 1;
}
#endif

static int
fixup_record (char *record, char *magic, unsigned long size)
{
    unsigned long start, count, offset;
    unsigned short fixup;

    if (*(int *)record != *(int *)magic)
	return 0;
    
    start = *(unsigned short *)(record + 4);
    count = *(unsigned short *)(record + 6);
    count--;
    
    if (size && blocksize * count != size)
	return 0;
    
    fixup = *(unsigned short *)(record + start);
    start += 2;
    offset = blocksize - 2;
    while (count--)
    {
	if(*(unsigned short *)(record + offset) != fixup)
	    return 0;
	
	*(unsigned short *)(record + offset) = *(unsigned short *)(record + start);
	
	start += 2;
	offset += blocksize;
    }
    return 1;
}

static void
rewind_run_list( RUNL *runl)
{
    runl->vcn = runl->svcn;
    runl->ptr = runl->start;
    runl->cnum0 = 0;
    runl->cnum = 0;
    runl->clen = 0;
}

static int
get_next_run (RUNL *runl)
{
    unsigned long t, n, v;

#ifdef DEBUG_NTFS
    printf("get_next_run: s=%d e=%d c=%d start=%x ptr=%x\n",
	   runl->svcn, runl->evcn, runl->vcn, runl->start, runl->ptr);
#endif

    runl->vcn += runl->clen;
    if (runl->vcn > runl->evcn)
    	return 0;

    t = *((runl->ptr)++);
    n = t & 0xf;
    runl->clen = 0;
    v = 1;
    
    while (n--)
    {
	runl->clen += v * (*(unsigned char *)((runl->ptr)++));
	v <<= 8;
    }
    
    n = (t >> 4) & 0xf;
    
    if (n == 0)
	runl->cnum = 0;
    else
    {
	unsigned long c = 0;
	v = 1;
	while(n--)
       	{
	    c += v * (*(unsigned char *)((runl->ptr)++));
	    v <<= 8;
	}
	
	if (c & (v>>1))
	    c -= v;
	runl->cnum0 += c;
	runl->cnum = runl->cnum0;
    }
#ifdef DEBUG_NTFS
    printf ("got_next_run: t=%x cluster %x len %x vcn=%x ecn=%x\n",
    	t, runl->cnum, runl->clen, runl->vcn, runl->evcn);
#endif
    return 1;
}

#ifndef NO_ATTRIBUTE_LIST
static void
init_run_list (char *attr, unsigned long len, RUNL *runl, unsigned long *initp)
{
    unsigned long allocated;
    /* int inited; */

    runl->svcn = *(unsigned long *)(attr + 0x10); /* only support 32 bit */
    runl->evcn = *(unsigned long *)(attr + 0x18); /* only support 32 bit */
    runl->start = attr + (*(unsigned short *)(attr + 0x20));
    allocated = *(unsigned long *)(attr + 0x28);
    
    if (initp)
       	*initp = *(unsigned long *)(attr + 0x38);
    
    if (! runl->evcn)
       	runl->evcn = (allocated - 1) / clustersize;
    
#ifdef DEBUG_NTFS
    printf("size %d allocated=%d inited=%d cegin=%x csize=%d vcn=%d-%d\n",
	    /*attr_size*/ *(unsigned long *)(attr+0x30),
	    /*allocated*/ *(unsigned long *)(attr+0x28),
	    /*attr_inited*/ *(unsigned long *)(attr+0x38),
	    /*cengin*/ *(unsigned short *)(attr+0x22),
	    /*csize*/ *(unsigned short *)(attr+0x40),
	    runl->svcn, runl->evcn);
#endif
    rewind_run_list(runl);
}
#endif


static int
find_attribute (char *mft, unsigned long type, char *name, char **attr, unsigned long *size, unsigned long *len, unsigned long *flag)
{
    unsigned long t, l, r, n, i, namelen;
    unsigned short *attr_name;

    n = strlen (name);
    r = mft_record_size - *(unsigned short *)(mft + 0x14);
    mft += *(unsigned short *)(mft + 0x14);
    while ((t = *(unsigned long *)mft) != -1)
    {
	l = *(unsigned long *)(mft+4);
	if (l > r)
	    break;
#ifdef DEBUG_NTFS
	printf("type = %x len = %d namelen=%d resident=%d compresed=%d attrno=%d\n",
		t, l,
		/*namelen*/ *(mft+9),
		//name = (unsigned short *)(mft + *(unsigned short *)(mft+10)),
		/*resident */ (*(mft+8) == 0),
		/*compressed*/ *(unsigned short *)(mft+12),
		/*attrno*/ *(unsigned short *)(mft+14));
#endif
	namelen = (*(mft + 9));
	if (t == type)
       	{
#ifndef STAGE1_5
#ifndef NO_ALTERNATE_DATASTREAM
	    if(is_ads_completion && type == at_data)
	    {
		if(namelen && namelen >= n &&
		   (! *(mft + 8)/*resident*/ || ! *(unsigned long *)(attr + 0x10)/*svcn==0*/))
		{
		    for (i = 0, attr_name = (unsigned short *)(mft + *(unsigned short *)(mft + 10)); i < n; i++)
			if (tolower(name[i]) != tolower(attr_name[i]))
			    break;
		    
		    if (i >= n)
		    {
			for(; i < namelen; i++)
			    name[i] = attr_name[i];
			
			name[i] = '\0';
			
			if (print_possibilities > 0)
			    print_possibilities = -print_possibilities;
			
			print_a_completion(fnbuf);
			
			name[n] = '\0';
		    }
		}
	    } else
#endif
#endif
	    if (namelen == n)
	    {
		for (i = 0, attr_name = (unsigned short *)(mft + *(unsigned short *)(mft + 10)); i < n; i++)
		    if(tolower(name[i]) != tolower(attr_name[i]))
			break;
		
		if (i >= n)
	       	{
		    if (flag)
			*flag = *(unsigned short *)(mft + 12);
		    
		    if (*(mft + 8) == 0)
		    {
			if (flag)
			    *flag |= ATTR_RESIDENT;
#ifdef DEBUG_NTFS
			printf("resident data at %x size %x indexed=%d\n",
			       /*data*/ *(unsigned short *)(mft+0x14),
			       /*attr_size*/ *(unsigned short *)(mft+0x10),
			       /*indexed*/ *(unsigned short *)(mft+0x16));
#endif
			if (attr)
			    *attr = mft + (*(unsigned short *)(mft + 0x14));
			
			if (size)
  			    *size = (*(unsigned short *)(mft + 0x10));
			
			if (len)
  			    *len = (*(unsigned short *)(mft + 0x10));
			
		    } else {
			
			if (attr)
  			    *attr = mft;
			
			if (size)
  			    *size = *(unsigned long *)(mft+0x30);
			
			if (len)
  			    *len = l;
		    }
		    
		    return 1;
		}
	    }
	}
	
	mft += l;
	r -= l;
    }
    return 0;
}

#ifndef NO_ATTRIBUTE_LIST
static unsigned long
get_next_attribute_list (MFTR *mftr, unsigned long *size)
{
    unsigned long l, t, mftno;
#ifdef DEBUG_NTFS
    printf("get_next_attribute_list: type=%x\n",mftr->attr_type);
#endif
again:
    while (mftr->attr_list_len > 0x14)
    {
	t = *(unsigned long *)(mftr->attr_list + 0);
	l = *(unsigned short *)(mftr->attr_list + 4);
#ifdef DEBUG_NTFS
	printf("attr_list type=%x len=%x remain=%x\n", t, l, mftr->attr_list_len);
#endif
	if(l == 0 || l > mftr->attr_list_len)
	    return 0;
	
	mftno = *(unsigned long *)(mftr->attr_list + 0x10);
	mftr->attr_list_len -= l;
	mftr->attr_list += l;
	
	if(t == mftr->attr_type)
	{
#ifdef DEBUG_NTFS
	printf("attr_list mftno=%x\n", mftno);
#endif
	    if (read_mft_record (mftno, mftr->mft2, (mftr == mmft)) == 0)
		break;
	    
	    if (find_attribute(mftr->mft2, mftr->attr_type, mftr->attr_name,
			&mftr->attr, size, &mftr->attr_len, &mftr->attr_flag))
		return 1;
	}
    }
#ifndef NO_NON_RESIDENT_ATTRIBUTE_LIST
    if (mftr->attr_list_off < mftr->attr_list_size)
    {
	unsigned long len = mftr->attr_list_size - mftr->attr_list_off;
	
	if (len > BLOCK_SIZE)
	    len = BLOCK_SIZE;

	if (mftr->attr_list_len)
	    memmove (mftr->attr_list_buf, mftr->attr_list, mftr->attr_list_len);
	
	mftr->attr_list = mftr->attr_list_buf;

	if (read_attribute (NULL, mftr->attr_list_off,
			mftr->attr_list_buf + mftr->attr_list_len,
			len, &mftr->attr_list_runl) != len)
	{
#ifdef DEBUG_NTFS
	    printf("CORRUPT NON-RESIDENT ATTRIBUTE_LIST\n");