/src/sleuthkit/tsk/fs/ntfs.cpp

Source
/*
** ntfs
** The Sleuth Kit
**
** Content and meta data layer support for the NTFS file system
**
** Brian Carrier [carrier <at> sleuthkit [dot] org]
** Copyright (c) 2006-2011 Brian Carrier, Basis Technology.  All Rights reserved
** Copyright (c) 2003-2005 Brian Carrier.  All rights reserved
**
** TASK
** Copyright (c) 2002 Brian Carrier, @stake Inc.  All rights reserved
**
** This software is distributed under the Common Public License 1.0
**
** Unicode added with support from I.D.E.A.L. Technology Corp (Aug '05)
**
*/
#include "tsk_fs_i.h"
#include "tsk_ntfs.h"

#include <ctype.h>

#include <memory>

#include "encryptionHelper.h"

/**
 * \file ntfs.c
 * Contains the TSK internal general NTFS processing code
 */
/*
 * NOTES TO SELF:
 *
 * - multiple ".." entries may exist
 */

/*
 * How are we to handle the META flag? Is the MFT $Data Attribute META?
 */


/* Macro to pass in both the epoch time value and the nano time value */
#define WITHNANO(x) x, (unsigned int)x##_nano


/* mini-design note:
 * The MFT has entries for every file and dir in the fs.
 * The first entry ($MFT) is for the MFT itself and it is used to find
 * the location of the entire table because it can become fragmented.
 * Therefore, the $Data attribute of $MFT is saved in the NTFS_INFO
 * structure for easy access.  We also use the size of the MFT as
 * a way to calculate the maximum MFT entry number (last_inum).
 *
 * Ok, that is simple, but getting the full $Data attribute can be tough
 * because $MFT may not fit into one MFT entry (i.e. an attribute list).
 * We need to process the attribute list attribute to find out which
 * other entries to process.  But, the attribute list attribute comes
 * before any $Data attribute (so it could refer to an MFT that has not
 * yet been 'defined').  Although, the $Data attribute seems to always
 * exist and define at least the run for the entry in the attribute list.
 *
 * So, the way this is solved is that generic mft_lookup is used to get
 * any MFT entry, even $MFT.  If $MFT is not cached then we calculate
 * the address of where to read based on multiplication and guessing.
 * When we are loading the $MFT, we set 'loading_the_MFT' to 1 so
 * that we can update things as we go along.  When we read $MFT we
 * read all the attributes and save info about the $Data one.  If
 * there is an attribute list, we will have the location of the
 * additional MFT in the cached $Data location, which will be
 * updated as we process the attribute list.  After each MFT
 * entry that we process while loading the MFT, the 'final_inum'
 * value is updated to reflect what we can currently load so
 * that the sanity checks still work.
 */


/**********************************************************************
 *
 *  MISC FUNCS
 *
 **********************************************************************/

/* convert the NT Time (UTC hundred nanoseconds from 1/1/1601)
 * to UNIX (UTC seconds from 1/1/1970)
 *
 * The basic calculation is to remove the nanoseconds and then
 * subtract the number of seconds between 1601 and 1970
 * i.e. TIME - DELTA
 *
 * Returns 0 if NT date is outside of Unix range
 *
 */
uint32_t
nt2unixtime(uint64_t ntdate)
{
// (369*365 + 89) * 24 * 3600 * 10000000
#define NSEC_BTWN_1601_1970 (uint64_t)(116444736000000000ULL)

    // return 0 if before 1970
    if (ntdate < NSEC_BTWN_1601_1970)
        return 0;

    ntdate -= (uint64_t) NSEC_BTWN_1601_1970;
    ntdate /= (uint64_t) 10000000;

    // return if beyond 32-bit epoch range
    if (ntdate > 0xffffffffULL)
        return 0;

    return (uint32_t) ntdate;
}

/* convert the NT Time (UTC hundred nanoseconds from 1/1/1601)
 * to only the nanoseconds
 *
 */
uint32_t
nt2nano(uint64_t ntdate)
{
    return (uint32_t) (ntdate % 10000000)*100;
}


/**********************************************************************
 *
 * Lookup Functions
 *
 **********************************************************************/




/**
 * Read an MFT entry and save it in raw form in the given buffer.
 * NOTE: This will remove the update sequence integrity checks in the
 * structure.
 *
 * @param a_ntfs File system to read from
 * @param a_buf Buffer to save raw data to.  Must be of size NTFS_INFO.mft_rsize_b
 * @param a_mftnum Address of MFT entry to read
 * @param mft_start_addr Within-file-system byte address of start of MFT entry
 *
 * @returns Error value
 */
TSK_RETVAL_ENUM
ntfs_dinode_lookup(NTFS_INFO * a_ntfs, char *a_buf, TSK_INUM_T a_mftnum, TSK_OFF_T * mft_start_addr)
{
    TSK_OFF_T mftaddr_b, mftaddr2_b, offset;
    size_t mftaddr_len = 0;
    int i;
    TSK_FS_INFO *fs = (TSK_FS_INFO *) & a_ntfs->fs_info;
    TSK_FS_ATTR_RUN *data_run;
    ntfs_upd *upd;
    uint16_t sig_seq;
    ntfs_mft *mft;


    /* sanity checks */
    if (!a_buf) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("mft_lookup: null mft buffer");
        return TSK_ERR;
    }

    if (a_mftnum < fs->first_inum) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("mft_lookup: inode number is too small (%"
            PRIuINUM ")", a_mftnum);
        return TSK_ERR;
    }

    /* Because this code reads teh actual MFT, we need to make sure we
     * decrement the last_inum because the last value is a special value
     * for the ORPHANS directory */
    if (a_mftnum > fs->last_inum - 1) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("mft_lookup: inode number is too large (%"
            PRIuINUM ")", a_mftnum);
        return TSK_ERR;
    }


    if (tsk_verbose)
        tsk_fprintf(stderr,
            "ntfs_dinode_lookup: Processing MFT %" PRIuINUM "\n",
            a_mftnum);

    /* If mft_data (the cached $Data attribute of $MFT) is not there yet,
     * then we have not started to load $MFT yet.  In that case, we will
     * 'cheat' and calculate where it goes.  This should only be for
     * $MFT itself, in which case the calculation is easy
     */
    if (!a_ntfs->mft_data) {

        /* This is just a random check with the assumption being that
         * we don't want to just do a guess calculation for a very large
         * MFT entry
         */
        if (a_mftnum > NTFS_LAST_DEFAULT_INO) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_ARG);
            tsk_error_set_errstr
                ("Error trying to load a high MFT entry when the MFT itself has not been loaded (%"
                PRIuINUM ")", a_mftnum);
            return TSK_ERR;
        }

        mftaddr_b = a_ntfs->root_mft_addr + a_mftnum * a_ntfs->mft_rsize_b;
        mftaddr2_b = 0;
    }
    else {
        /* The MFT may not be in consecutive clusters, so we need to use its
         * data attribute run list to find out what address to read
         *
         * This is why we cached it
         */

        // will be set to the address of the MFT entry
        mftaddr_b = mftaddr2_b = 0;

        /* The byte offset within the $Data stream */
        offset = a_mftnum * a_ntfs->mft_rsize_b;

        /* NOTE: data_run values are in clusters
         *
         * cycle through the runs in $Data and identify which
         * has the MFT entry that we want
         */
        for (data_run = a_ntfs->mft_data->nrd.run;
            data_run != NULL; data_run = data_run->next) {

            /* Test for possible overflows / error conditions */
            if ((offset < 0) || (data_run->len >= (TSK_DADDR_T)(LLONG_MAX / a_ntfs->csize_b))){
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                ("ntfs_dinode_lookup: Overflow when calculating run length");
                return TSK_COR;
            }

            /* The length of this specific run */
            TSK_OFF_T run_len = data_run->len * a_ntfs->csize_b;

            /* Is our MFT entry is in this run somewhere ? */
            if (offset < run_len) {

                if (tsk_verbose)
                    tsk_fprintf(stderr,
                        "ntfs_dinode_lookup: Found in offset: %"
                        PRIuDADDR "  size: %" PRIuDADDR " at offset: %"
            PRIdOFF "\n", data_run->addr, data_run->len,
                        offset);

                /* special case where the MFT entry crosses
                 * a run (only happens when cluster size is 512-bytes
                 * and there are an odd number of clusters in the run)
                 */
                if (run_len < offset + a_ntfs->mft_rsize_b) {

                    if (tsk_verbose)
                        tsk_fprintf(stderr,
                            "ntfs_dinode_lookup: Entry crosses run border\n");

                    if (data_run->next == NULL) {
                        tsk_error_reset();
                        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                        tsk_error_set_errstr
                            ("mft_lookup: MFT entry crosses a cluster and there are no more clusters!");
                        return TSK_COR;
                    }

                    /* Assign address where the remainder of the entry is */
                    mftaddr2_b = data_run->next->addr * a_ntfs->csize_b;
                    /* this should always be 512, but just in case */
                    mftaddr_len = (size_t) (run_len - offset);
                }

                /* Assign address of where the MFT entry starts */
                mftaddr_b = data_run->addr * a_ntfs->csize_b + offset;
                if (tsk_verbose)
                    tsk_fprintf(stderr,
                        "ntfs_dinode_lookup: Entry address at: %"
            PRIdOFF "\n", mftaddr_b);
                break;
            }

            /* decrement the offset we are looking for */
            offset -= run_len;
        }

        /* Did we find it? */
        if (!mftaddr_b) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_INODE_NUM);
            tsk_error_set_errstr("mft_lookup: Error finding MFT entry %"
                PRIuINUM " in $MFT", a_mftnum);
            return TSK_ERR;
        }
    }


    /* can we do just one read or do we need multiple? */
    if (mftaddr2_b) {
        ssize_t cnt;
        /* read the first part into mft */
        cnt = tsk_fs_read(&a_ntfs->fs_info, mftaddr_b, a_buf, mftaddr_len);
        if (cnt != (ssize_t)mftaddr_len) {
            if (cnt >= 0) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_READ);
            }
            tsk_error_set_errstr2
                ("ntfs_dinode_lookup: Error reading MFT Entry (part 1) at %"
          PRIdOFF, mftaddr_b);
            return TSK_ERR;
        }

        /* read the second part into mft */
        cnt = tsk_fs_read
            (&a_ntfs->fs_info, mftaddr2_b,
            (char *) ((uintptr_t) a_buf + (uintptr_t) mftaddr_len),
            a_ntfs->mft_rsize_b - mftaddr_len);
        if (cnt != (ssize_t)(a_ntfs->mft_rsize_b - mftaddr_len)) {
            if (cnt >= 0) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_READ);
            }
            tsk_error_set_errstr2
                ("ntfs_dinode_lookup: Error reading MFT Entry (part 2) at %"
          PRIdOFF, mftaddr2_b);
            return TSK_ERR;
        }
    }
    else {
        ssize_t cnt;
        /* read the raw entry into mft */
        cnt =
            tsk_fs_read(&a_ntfs->fs_info, mftaddr_b, a_buf,
            a_ntfs->mft_rsize_b);
        if (cnt != a_ntfs->mft_rsize_b) {
            if (cnt >= 0) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_READ);
            }
            tsk_error_set_errstr2
                ("ntfs_dinode_lookup: Error reading MFT Entry at %"
          PRIdOFF, mftaddr_b);
            return TSK_ERR;
        }
    }

    /* A nonzero address means that mftaddr_b has been requested for export */
    if (mft_start_addr) {
        *mft_start_addr = mftaddr_b;
    }

    /* Sanity Check */
#if 0
    /* This is no longer applied because it caused too many problems
     * with images that had 0 and 1 etc. as values.  Testing shows that
     * even Windows XP doesn't care if entries have an invalid entry, so
     * this is no longer checked.  The update sequence check should find
     * corrupt entries
     * */
    if ((tsk_getu32(fs->endian, mft->magic) != NTFS_MFT_MAGIC)
        && (tsk_getu32(fs->endian, mft->magic) != NTFS_MFT_MAGIC_BAAD)
        && (tsk_getu32(fs->endian, mft->magic) != NTFS_MFT_MAGIC_ZERO)) {
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr("entry %d has an invalid MFT magic: %x",
            mftnum, tsk_getu32(fs->endian, mft->magic));
        return 1;
    }
#endif
    /* The MFT entries have error and integrity checks in them
     * called update sequences.  They must be checked and removed
     * so that later functions can process the data as normal.
     * They are located in the last 2 bytes of each 512-bytes of data.
     *
     * We first verify that the the 2-byte value is a give value and
     * then replace it with what should be there
     */
    /* sanity check so we don't run over in the next loop */
    mft = (ntfs_mft *) a_buf;
    if ((tsk_getu16(fs->endian, mft->upd_cnt) > 0) &&
        (((uint32_t) (tsk_getu16(fs->endian,
                        mft->upd_cnt) - 1) * NTFS_UPDATE_SEQ_STRIDE) >
            a_ntfs->mft_rsize_b)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr
            ("dinode_lookup: More Update Sequence Entries than MFT size");
        return TSK_COR;
    }
    uint16_t upd_cnt = tsk_getu16(fs->endian, mft->upd_cnt);
    uint16_t upd_off = tsk_getu16(fs->endian, mft->upd_off);

    // Make sure upd_cnt > 0 to prevent an integer wrap around.
    // NOTE: There is a bug here because upd_cnt can be for unused entries.
    // They are now skipped (as of July 2021). We shoudl refactor this code
    // to allow upd_cnt = 0.
    if ((upd_cnt == 0) || (upd_cnt > (((a_ntfs->mft_rsize_b) / 2) + 1))) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr
            ("dinode_lookup: Invalid update count value out of bounds");
        return TSK_COR;
    }
    size_t mft_rsize_b = ((size_t) upd_cnt - 1) * 2;

    if ((size_t) upd_off + sizeof(ntfs_upd) > (a_ntfs->mft_rsize_b - mft_rsize_b)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr
            ("dinode_lookup: Update sequence would read past MFT size");
        return TSK_COR;
    }

    /* Apply the update sequence structure template */

    upd = (ntfs_upd *) ((uintptr_t) a_buf + upd_off);
    /* Get the sequence value that each 16-bit value should be */
    sig_seq = tsk_getu16(fs->endian, upd->upd_val);
    /* cycle through each sector */
    for (i = 1; i < tsk_getu16(fs->endian, mft->upd_cnt); i++) {
        uint8_t *new_val, *old_val;
        /* The offset into the buffer of the value to analyze */
        size_t offset = i * NTFS_UPDATE_SEQ_STRIDE - 2;

        /* Check that there is room in the buffer to read the current sequence value */
        if (offset + 2 > a_ntfs->mft_rsize_b) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
            tsk_error_set_errstr
            ("dinode_lookup: Ran out of data while parsing update sequence values");
            return TSK_COR;
        }

        /* get the current sequence value */
        uint16_t cur_seq =
            tsk_getu16(fs->endian, (uintptr_t) a_buf + offset);
        if (cur_seq != sig_seq) {
            /* get the replacement value */
            uint16_t cur_repl =
                tsk_getu16(fs->endian, &upd->upd_seq + (i - 1) * 2);
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_GENFS);

            tsk_error_set_errstr
                ("Incorrect update sequence value in MFT entry\nSignature Value: 0x%"
                PRIx16 " Actual Value: 0x%" PRIx16
                " Replacement Value: 0x%" PRIx16
                "\nThis is typically because of a corrupted entry",
                sig_seq, cur_seq, cur_repl);
            return TSK_COR;
        }

        new_val = &upd->upd_seq + (i - 1) * 2;
        old_val = (uint8_t *) ((uintptr_t) a_buf + offset);
        /*
           if (tsk_verbose)
           tsk_fprintf(stderr,
           "ntfs_dinode_lookup: upd_seq %i   Replacing: %.4"
           PRIx16 "   With: %.4" PRIx16 "\n", i,
           tsk_getu16(fs->endian, old_val), tsk_getu16(fs->endian,
           new_val));
         */
        *old_val++ = *new_val++;
        *old_val = *new_val;
    }

    return TSK_OK;
}



/*
 * given a cluster, return the allocation status or
 * -1 if an error occurs
 */
static int
is_clustalloc(NTFS_INFO * ntfs, TSK_DADDR_T addr)
{
    int bits_p_clust, b;
    TSK_DADDR_T base;
    int8_t ret;
    bits_p_clust = 8 * ntfs->fs_info.block_size;

    /* While we are loading the MFT, assume that everything
     * is allocated.  This should only be needed when we are
     * dealing with an attribute list ...
     */
    if (ntfs->loading_the_MFT == 1) {
        return 1;
    }
    else if (ntfs->bmap == NULL) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);

        tsk_error_set_errstr("is_clustalloc: Bitmap pointer is null: %"
            PRIuDADDR "\n", addr);
        return -1;
    }

    /* Is the cluster too big? */
    if (addr > ntfs->fs_info.last_block) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr("is_clustalloc: cluster too large");
        return -1;
    }

    /* identify the base cluster in the bitmap file */
    base = addr / bits_p_clust;
    b = (int) (addr % bits_p_clust);

    tsk_take_lock(&ntfs->lock);

    /* is this the same as in the cached buffer? */
    if (base != ntfs->bmap_buf_off) {
        TSK_DADDR_T c = base;
        TSK_FS_ATTR_RUN *run;
        TSK_DADDR_T fsaddr = 0;
        ssize_t cnt;

        /* get the file system address of the bitmap cluster */
        for (run = ntfs->bmap; run; run = run->next) {
            if (run->len <= c) {
                c -= run->len;
            }
            else {
                fsaddr = run->addr + c;
                break;
            }
        }

        if (fsaddr == 0) {
            tsk_release_lock(&ntfs->lock);
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_BLK_NUM);
            tsk_error_set_errstr
                ("is_clustalloc: cluster not found in bitmap: %" PRIuDADDR
                "", c);
            return -1;
        }
        if (fsaddr > ntfs->fs_info.last_block) {
            tsk_release_lock(&ntfs->lock);
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_BLK_NUM);
            tsk_error_set_errstr
                ("is_clustalloc: Cluster in bitmap too large for image: %"
                PRIuDADDR, fsaddr);
            return -1;
        }
        ntfs->bmap_buf_off = base;
        cnt = tsk_fs_read_block
            (&ntfs->fs_info, fsaddr, ntfs->bmap_buf,
            ntfs->fs_info.block_size);
        if (cnt != ntfs->fs_info.block_size) {
            tsk_release_lock(&ntfs->lock);
            if (cnt >= 0) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_READ);
            }
            tsk_error_set_errstr2
                ("is_clustalloc: Error reading bitmap at %" PRIuDADDR,
                fsaddr);
            return -1;
        }
    }

    /* identify if the cluster is allocated or not */
    ret = (isset(ntfs->bmap_buf, b)) ? 1 : 0;

    tsk_release_lock(&ntfs->lock);
    return ret;
}



/**********************************************************************
 *
 *  TSK_FS_ATTR functions
 *
 **********************************************************************/


/**
 * Process a non-resident runlist and convert its contents into the generic fs_attr_run
 * structure.
 * @param ntfs File system that attribute is located in.
 * @param start_vcn The starting VCN for this run.
 * @param runlist The raw runlist data from the MFT entry.
 * @param runlist_size The size of the raw runlist data from the MFT entry.
 * @param a_data_run_head [out] Pointer to pointer of run that is created. (NULL on error and for $BadClust - special case because it is a sparse file for the entire FS).
 * @param totlen [out] Pointer to location where total length of run (in bytes) can be returned (or NULL)
 * @param mnum MFT entry address
 *
 * @returns Return status of error, corrupt, or OK (note a_data_run can be NULL even when OK is returned if $BadClust is encountered)
 */
static TSK_RETVAL_ENUM
ntfs_make_data_run(NTFS_INFO * ntfs, TSK_OFF_T start_vcn,
    ntfs_runlist * runlist_head, uint32_t runlist_size, TSK_FS_ATTR_RUN ** a_data_run_head,
    TSK_OFF_T * totlen, TSK_INUM_T mnum)
{
    TSK_FS_INFO *fs = (TSK_FS_INFO *) ntfs;
    ntfs_runlist *run;
    TSK_FS_ATTR_RUN *data_run, *data_run_prev = NULL;
    unsigned int i, idx;
    TSK_DADDR_T prev_addr = 0;
    TSK_OFF_T file_offset = start_vcn;
    uint32_t runlist_offset = 0;

    run = runlist_head;
    *a_data_run_head = NULL;

    /* initialize if non-NULL */
    if (totlen)
        *totlen = 0;

    if (runlist_size < 1) {
        return TSK_ERR;
    }

    /* Cycle through each run in the runlist
     * We go until we find an entry with no length
     * An entry with offset of 0 is for a sparse run
     */
    while ((runlist_offset < runlist_size) && NTFS_RUNL_LENSZ(run) != 0) {
        int64_t addr_offset = 0;

        /* allocate a new tsk_fs_attr_run */
        data_run = tsk_fs_attr_run_alloc();
        if (data_run == NULL) {
            tsk_fs_attr_run_free(*a_data_run_head);
            *a_data_run_head = NULL;
            return TSK_ERR;
        }

        /* make the list, unless its the first pass & then we set the head */
        if (data_run_prev)
            data_run_prev->next = data_run;
        else
            *a_data_run_head = data_run;
        data_run_prev = data_run;

        /* These fields are a variable number of bytes long
         * these for loops are the equivalent of the getuX macros
         */
        idx = 0;

        /* Get the length of this run.
         * A length of more than eight bytes will not fit in the
         * 64-bit length field (and is likely corrupt)
         */
        if (NTFS_RUNL_LENSZ(run) > 8 || (uint32_t) NTFS_RUNL_LENSZ(run) > runlist_size - runlist_offset - 1) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
            tsk_error_set_errstr
            ("ntfs_make_run: Run length is too large to process");
            tsk_fs_attr_run_free(*a_data_run_head);
            *a_data_run_head = NULL;
            return TSK_COR;
        }
        for (i = 0, data_run->len = 0; i < NTFS_RUNL_LENSZ(run); i++) {
            data_run->len |= ((uint64_t)(run->buf[idx++]) << (i * 8));
            if (tsk_verbose)
                tsk_fprintf(stderr,
                    "ntfs_make_data_run: Len idx: %i cur: %"
                    PRIu8 " (%" PRIx8 ") tot: %" PRIuDADDR
                    " (%" PRIxDADDR ")\n", i,
                    run->buf[idx - 1], run->buf[idx - 1],
                    data_run->len, data_run->len);
        }

        /* Sanity check on length */
        if (data_run->len > fs->block_count) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
            tsk_error_set_errstr
                ("ntfs_make_run: Run length is larger than file system");
            tsk_fs_attr_run_free(*a_data_run_head);
            *a_data_run_head = NULL;
            return TSK_COR;
        }

        data_run->offset = file_offset;
        file_offset += data_run->len;

        /* Update the length if we were passed a value */
        if (totlen)
            *totlen += (data_run->len * ntfs->csize_b);

        /* Get the address offset of this run.
         * An address offset of more than eight bytes will not fit in the
         * 64-bit addr_offset field (and is likely corrupt)
         */
        if (NTFS_RUNL_OFFSZ(run) > 8 || (uint32_t) ( NTFS_RUNL_LENSZ(run) + NTFS_RUNL_OFFSZ(run) ) > runlist_size - runlist_offset - 1) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
            tsk_error_set_errstr
            ("ntfs_make_run: Run address offset is too large to process");
            tsk_fs_attr_run_free(*a_data_run_head);
            *a_data_run_head = NULL;
            return TSK_COR;
        }
        for (i = 0, data_run->addr = 0; i < NTFS_RUNL_OFFSZ(run); i++) {
            //data_run->addr |= (run->buf[idx++] << (i * 8));
            addr_offset |= ((int64_t)(run->buf[idx++]) << (i * 8));
            if (tsk_verbose)
                tsk_fprintf(stderr,
                    "ntfs_make_data_run: Off idx: %i cur: %"
                    PRIu8 " (%" PRIx8 ") tot: %" PRIuDADDR
                    " (%" PRIxDADDR ")\n", i,
                    run->buf[idx - 1], run->buf[idx - 1], addr_offset,
                    addr_offset);
        }

        /* addr_offset value is signed so extend it to 64-bits */
        if ((int8_t) run->buf[idx - 1] < 0) {
            for (; i < sizeof(addr_offset); i++)
                addr_offset |= (int64_t) ((int64_t) 0xff << (i * 8));
        }

        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_make_data_run: Signed addr_offset: %"
        PRId64 " Previous address: %"
        PRIuDADDR "\n", addr_offset, prev_addr);

        /* The NT 4.0 version of NTFS uses an offset of -1 to represent
         * a hole, so add the sparse flag and make it look like the 2K
         * version with a offset of 0
         *
         * A user reported an issue where the $Bad file started with
         * its offset as -1 and it was not NT (maybe a conversion)
         * Change the check now to not limit to NT, but make sure
         * that it is the first run
         */
        if (((addr_offset == -1) && (prev_addr == 0))
            || ((addr_offset == -1)
                && (ntfs->ver == NTFS_VINFO_NT))) {
            data_run->flags = (TSK_FS_ATTR_RUN_FLAG_ENUM) (data_run->flags | TSK_FS_ATTR_RUN_FLAG_SPARSE);
            data_run->addr = 0;
            if (tsk_verbose)
                tsk_fprintf(stderr, "ntfs_make_data_run: Sparse Run\n");
        }

        /* A Sparse file has a run with an offset of 0
         * there is a special case though of the BOOT MFT entry which
         * is the super block and has a legit offset of 0.
         *
         * The value given is a delta of the previous offset, so add
         * them for non-sparse files
         *
         * For sparse files the next run will have its offset relative
         * to the current "prev_addr" so skip that code
         */
        // @@@ BC: we'll need to pass in an inode value for this check
        else if ((addr_offset) || (mnum == NTFS_MFT_BOOT)) {

            data_run->addr = prev_addr + addr_offset;
            prev_addr = data_run->addr;

            /* Sanity check on length and offset */
            if (data_run->addr + data_run->len > fs->block_count) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                    ("ntfs_make_run: Run offset and length is larger than file system");
                tsk_fs_attr_run_free(*a_data_run_head);
                *a_data_run_head = NULL;
                return TSK_COR;
            }

        }
        else {
            data_run->flags = (TSK_FS_ATTR_RUN_FLAG_ENUM) (data_run->flags | TSK_FS_ATTR_RUN_FLAG_SPARSE);
            if (tsk_verbose)
                tsk_fprintf(stderr, "ntfs_make_data_run: Sparse Run\n");
        }

        /* Advance run */
        uint32_t run_size = 1 + NTFS_RUNL_LENSZ(run) + NTFS_RUNL_OFFSZ(run);
        run = (ntfs_runlist *) ((uintptr_t) run + run_size);

        // Abritrary limit runlist_offset at INT32_MAX ((1 << 31) - 1)
        if (run_size > (((uint32_t) 1UL << 31 ) -1) - runlist_offset) {
            return TSK_ERR;
        }
        runlist_offset += run_size;
    }

    /* special case for $BADCLUST, which is a sparse file whose size is
     * the entire file system.
     *
     * If there is only one run entry and it is sparse, then there are no
     * bad blocks, so get rid of it.
     */
    if ((*a_data_run_head != NULL)
        && ((*a_data_run_head)->next == NULL)
        && ((*a_data_run_head)->flags & TSK_FS_ATTR_RUN_FLAG_SPARSE)
        && ((*a_data_run_head)->len == fs->last_block + 1)) {
        tsk_fs_attr_run_free(*a_data_run_head);
        *a_data_run_head = NULL;
    }

    return TSK_OK;
}



/*********** UNCOMPRESSION CODE *************/


/*
 * NTFS Breaks compressed data into compression units, which are
 * typically 16 clusters in size. If the data in the comp  unit
 * compresses to something smaller than 16 clusters then the
 * compressed data is stored and the rest of the compression unit
 * is filled with sparse clusters. The entire compression unit
 * can also be sparse.
 *
 * The uncompressed content in the compression unit is further broken
 * into 4k (pre-compression) blocks.  When stored, each 4k block has
 * a 2-byte header that identifies the compressed size (and if there
 * was compression).
 *
 * The compressed data is a series of token groups.  Each token group
 * contains a 1-byte header and 8 tokens.  The 8-bits in the token
 * group header identify the type of each token in the group.
 *
 * There are two types of tokens.
 * Symbol tokens are 1 byte in length and the 1-byte value is the value
 * for that position in the file and it should be direcly copied into the
 * uncompressed data.  Phrase tokens identify a previous run of data
 * in the same compression unit that should be
 * copied to the current location.  These contain offset and length info.
 *
 * The attribute will have enough cluster addresses to store all of
 * the content, but the addresses will be 0 in the compression unit
 * if it is all sparse and the ending clusters will be 0 in the
 * compression unit if they are not needed.
 *
 */

 /* Variables used for ntfs_uncompress() method */
typedef struct {
    char *uncomp_buf;           // Buffer for uncompressed data
    char *comp_buf;             // buffer for compressed data
    size_t comp_len;            // number of bytes used in compressed data buffer
    size_t uncomp_idx;          // Index into buffer for next byte
    size_t buf_size_b;          // size of both buffers in bytes (1 compression unit)
} NTFS_COMP_INFO;


/**
 * Reset the values in the NTFS_COMP_INFO structure.  We need to
 * do this in between every compression unit that we process in the file.
 *
 * @param comp Structure to reset
 */
static void
ntfs_uncompress_reset(NTFS_COMP_INFO * comp)
{
    memset(comp->uncomp_buf, 0, comp->buf_size_b);
    comp->uncomp_idx = 0;
    memset(comp->comp_buf, 0, comp->buf_size_b);
    comp->comp_len = 0;
}

/**
 * Setup the NTFS_COMP_INFO structure with a buffer and
 * initialize the basic settings.
 *
 * @param fs File system state information
 * @param comp Compression state information to initialize
 * @param compunit_size_c The size (in clusters) of a compression
 * unit
 * @return 1 on error and 0 on success
 */
static int
ntfs_uncompress_setup(TSK_FS_INFO * fs, NTFS_COMP_INFO * comp,
    uint32_t compunit_size_c)
{
    if (fs->block_size == 0 || compunit_size_c == 0) {
        return 1;
    }
    comp->buf_size_b = fs->block_size * compunit_size_c;

    // Detect an integer overflow e.g. 65536 * 65536
    if (comp->buf_size_b < fs->block_size) {
        return 1;
    }

    if ((comp->uncomp_buf = (char*) tsk_malloc(comp->buf_size_b)) == NULL) {
        comp->buf_size_b = 0;
        return 1;
    }
    if ((comp->comp_buf = (char*) tsk_malloc(comp->buf_size_b)) == NULL) {
        free(comp->uncomp_buf);
        comp->uncomp_buf = NULL;
        comp->buf_size_b = 0;
        return 1;
    }

    ntfs_uncompress_reset(comp);

    return 0;
}

static void
ntfs_uncompress_done(NTFS_COMP_INFO * comp)
{
    free(comp->uncomp_buf);
    comp->uncomp_buf = NULL;
    free(comp->comp_buf);
    comp->comp_buf = NULL;
    comp->buf_size_b = 0;
}


 /**
  * Uncompress the block of data in comp->comp_buf.
  * Store the result in the comp->uncomp_buf.
  *
  * @param comp Compression unit structure
  *
  * @returns 1 on error and 0 on success
  */
static uint8_t
ntfs_uncompress_compunit(NTFS_COMP_INFO * comp)
{
    size_t cl_index;
    uint8_t recover_data = 0;

    tsk_error_reset();

    comp->uncomp_idx = 0;

    /* Cycle through the compressed data
     * We maintain state using different levels of loops.
     * We use +1 here because the size value at start of block is 2 bytes.
     */
    for (cl_index = 0; cl_index + 1 < comp->comp_len;) {
        size_t blk_end;         // index into the buffer to where block ends
        size_t blk_size;        // size of the current block
        uint8_t iscomp;         // set to 1 if block is compressed
        size_t blk_st_uncomp;   // index into uncompressed buffer where block started
        uint16_t sb_header;     // subblock header

        sb_header = tsk_getu16(TSK_LIT_ENDIAN, comp->comp_buf + cl_index);

        // If the sb_header isn't set, we just fill the rest of the buffer with zeros.
        // This seems to be what several different NTFS implementations do.
        if (sb_header == 0) {
            memset(comp->uncomp_buf + comp->uncomp_idx, 0, comp->buf_size_b - comp->uncomp_idx);
            comp->uncomp_idx = comp->buf_size_b;
            break;
        }

        blk_size = (sb_header & 0x0FFF) + 3;

        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_uncompress_compunit: Start compression block (length=%" PRIuSIZE " index=%" PRIuSIZE
                " compressed buffer size=%" PRIuSIZE ")\n",
                blk_size, cl_index, comp->comp_len);

        // this seems to indicate end of block
        if (blk_size == 3)
            break;

        blk_end = cl_index + blk_size;
        if (blk_end > comp->comp_len) {
            blk_end = comp->comp_len - 1;
            if (tsk_verbose)
                tsk_fprintf(stderr,
                    "WARNING: ntfs_uncompress_compunit: Compression block length longer than buffer length. Attempting to continue.\n");
            recover_data = 1;
           // return 0; // zero out the entire block
           // if we don't return 0, let the function continue to display as much decompressed data as possible
        }

        /* The MSB identifies if the block is compressed */
        iscomp = ((sb_header & 0x8000) != 0);

        // keep track of where this block started in the buffer
        blk_st_uncomp = comp->uncomp_idx;
        cl_index += 2;

        // the 4096 size seems to occur at the same times as no compression
        if ((iscomp) && (blk_size - 2 != 4096)) {
            if (tsk_verbose)
                tsk_fprintf(stderr, "ntfs_uncompress_compunit: Compression block is compressed\n");

            // cycle through the token groups in the block
            while (cl_index < blk_end) {
                int a;

                // get the header header
                unsigned char header = comp->comp_buf[cl_index];
                cl_index++;

                if (tsk_verbose)
                    tsk_fprintf(stderr,
                        "ntfs_uncompress_compunit: Token Group Header: %x\n", header);

                for (a = 0; a < 8 && cl_index < blk_end; a++) {

                    /* Determine token type and parse appropriately. *
                     * Symbol tokens are the symbol themselves, so copy it
                     * into the uncompressed buffer
                     */
                    if ((header & NTFS_TOKEN_MASK) == NTFS_SYMBOL_TOKEN) {
                        if (tsk_verbose)
                            tsk_fprintf(stderr,
                                "ntfs_uncompress_compunit: Symbol Token: (offset %"
                                PRIuSIZE ")\n", cl_index);

                        if (comp->uncomp_idx >= comp->buf_size_b) {
                            tsk_error_set_errno(TSK_ERR_FS_FWALK);
                            tsk_error_set_errstr
                                ("ntfs_uncompress_compunit: Trying to write past end of uncompression buffer: %"
                                PRIuSIZE "", comp->uncomp_idx);
                            return 1;
                        }
                        comp->uncomp_buf[comp->uncomp_idx++] =
                            comp->comp_buf[cl_index];

                        cl_index++;
                    }

                    /* Otherwise, it is a phrase token, which points back
                     * to a previous sequence of bytes.
                     */
                    else {
                        size_t i;
                        int shift;
                        size_t start_position_index = 0;
                        size_t end_position_index = 0;
                        unsigned int offset = 0;
                        unsigned int length = 0;
                        uint16_t pheader;

                        if (cl_index + 1 >= blk_end) {
                            tsk_error_set_errno(TSK_ERR_FS_FWALK);
                            tsk_error_set_errstr
                                ("ntfs_uncompress_compunit: Phrase token index is past end of block: %d",
                                a);
                            return 1;
                        }

                        pheader =
                            ((((comp->comp_buf[cl_index +
                                            1]) << 8) & 0xFF00) |
                            (comp->comp_buf[cl_index] & 0xFF));
                        cl_index += 2;


                        /* The number of bits for the start and length
                         * in the 2-byte header change depending on the
                         * location in the compression unit.  This identifies
                         * how many bits each has */
                        shift = 0;
                        for (i =
                            comp->uncomp_idx -
                            blk_st_uncomp - 1; i >= 0x10; i >>= 1) {
                            shift++;
                        }
                        if (shift > 12) {
                            tsk_error_reset();
                            tsk_error_set_errno(TSK_ERR_FS_FWALK);
                            tsk_error_set_errstr
                            ("ntfs_uncompress_compunit: Shift is too large: %d", shift);
                            return 1;
                        }

                        //tsk_fprintf(stderr, "Start: %X  Shift: %d  UnComp_IDX %d  BlkStart: %lu  BlkIdx: %d  BlkSize: %d\n", (int)(comp->uncomp_idx - comp->blk_st - 1), shift, comp->uncomp_idx, comp->blk_st, comp->blk_idx, comp->blk_size);

                        offset = (pheader >> (12 - shift)) + 1;
                        length = (pheader & (0xFFF >> shift)) + 2;

                        start_position_index = comp->uncomp_idx - offset;
                        end_position_index = start_position_index + length;

                        if (tsk_verbose)
                            tsk_fprintf(stderr,
                                "ntfs_uncompress_compunit: Phrase Token: (offset %"
                                PRIuSIZE ")\tLen: %d\tPrevOffset: %d\tHeader=%x\n", cl_index-2,
                                length, offset, pheader);

                        /* Sanity checks on values */
                        if (offset > comp->uncomp_idx) {
                            tsk_error_reset();
                            tsk_error_set_errno(TSK_ERR_FS_FWALK);
                            tsk_error_set_errstr
                                ("ntfs_uncompress_compunit: Phrase token offset is too large:  %d (max: %"
                                PRIuSIZE ")", offset, comp->uncomp_idx);
                            return 1;
                        }
                        else if (length + start_position_index >
                            comp->buf_size_b) {
                            tsk_error_reset();
                            tsk_error_set_errno(TSK_ERR_FS_FWALK);
                            tsk_error_set_errstr
                                ("ntfs_uncompress_compunit: Phrase token length is too large:  %d (max: %" PRIuSIZE")",
                                length,
                                comp->buf_size_b - start_position_index);
                            return 1;
                        }
                        else if (end_position_index -
                            start_position_index + 1 >
                            comp->buf_size_b - comp->uncomp_idx) {
                            tsk_error_reset();
                            tsk_error_set_errno(TSK_ERR_FS_FWALK);
                            tsk_error_set_errstr
                                ("ntfs_uncompress_compunit: Phrase token length is too large for rest of uncomp buf:  %" PRIuSIZE" (max: %"
                                PRIuSIZE ")",
                                end_position_index - start_position_index +
                                1, comp->buf_size_b - comp->uncomp_idx);
                            return 1;
                        }

                        for (;
                            start_position_index <= end_position_index
                            && comp->uncomp_idx < comp->buf_size_b;
                            start_position_index++) {

                            // Copy the previous data to the current position
                            comp->uncomp_buf[comp->uncomp_idx++]
                                = comp->uncomp_buf[start_position_index];
                        }
                    }
                    header >>= 1;
                }               // end of loop inside of token group

            }                   // end of loop inside of block
        }

        // this block contains uncompressed data
        else {
            if (tsk_verbose)
                tsk_fprintf(stderr, "ntfs_uncompress_compunit: Block size is not compressed\n");

            while (cl_index < blk_end && cl_index < comp->comp_len) {
                /* This seems to happen only with corrupt data -- such as
                 * when an unallocated file is being processed... */
                if (comp->uncomp_idx >= comp->buf_size_b) {
                    tsk_error_reset();
                    tsk_error_set_errno(TSK_ERR_FS_FWALK);
                    tsk_error_set_errstr
                        ("ntfs_uncompress_compunit: Trying to write past end of uncompression buffer (1) -- corrupt data?)");
                    return 1;
                }

                // Place data in uncompression_buffer
                comp->uncomp_buf[comp->uncomp_idx++] =
                    comp->comp_buf[cl_index++];
            }
        }
    }                           // end of loop inside of compression unit
    // if we are attempting to recover, we may not have decompressed an entire CU. Set uncomp_idx to the expected size.
    if (recover_data) {
        comp->uncomp_idx = comp->buf_size_b;
    }
    return 0;
}



/**
 * Process a compression unit and return the decompressed data in a buffer in comp.
 *
 * @param ntfs File system
 * @param comp Compression state info (output will be stored in here)
 * @param comp_unit List of addresses that store compressed data
 * @param comp_unit_size Number of addresses in comp_unit
 * @returns 1 on error and 0 on success
 */
static uint8_t
ntfs_proc_compunit(NTFS_INFO * ntfs, NTFS_COMP_INFO * comp,
    TSK_DADDR_T * comp_unit, uint32_t comp_unit_size)
{
    TSK_FS_INFO *fs = (TSK_FS_INFO *) ntfs;
    int sparse;
    uint64_t a;

    /* With compressed attributes, there are three scenarios.
     * 1: The compression unit is not compressed,
     * 2: The compression unit is sparse
     * 3: The compression unit is compressed
     */

    /* Check if the entire compression unit is sparse */
    sparse = 1;
    for (a = 0; a < comp_unit_size && sparse == 1; a++) {
        if (comp_unit[a]) {
            sparse = 0;
            break;
        }
    }

    /* Entire comp unit is sparse... */
    if (sparse) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_proc_compunit: Unit is fully sparse\n");

        memset(comp->uncomp_buf, 0, comp->buf_size_b);
        comp->uncomp_idx = comp->buf_size_b;
    }

    /* Check if the end of the unit is sparse, which means the
     * unit is compressed */
    else if (comp_unit[comp_unit_size - 1] == 0) {

        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_proc_compunit: Unit is compressed\n");

        // load up the compressed buffer so we can decompress it
        ntfs_uncompress_reset(comp);
        for (a = 0; a < comp_unit_size; a++) {
            ssize_t cnt;

            if (comp_unit[a] == 0)
                break;

            /* To get the uncompressed size, we must uncompress the
             * data -- even if addresses are only needed */
            cnt =
                tsk_fs_read_block(fs, comp_unit[a],
                &comp->comp_buf[comp->comp_len], fs->block_size);
            if (cnt != fs->block_size) {
                if (cnt >= 0) {
                    tsk_error_reset();
                    tsk_error_set_errno(TSK_ERR_FS_READ);
                }
                tsk_error_set_errstr2
                    ("ntfs_proc_compunit: Error reading block at %"
                    PRIuDADDR, comp_unit[a]);
                return 1;
            }
            comp->comp_len += fs->block_size;
        }

        if (ntfs_uncompress_compunit(comp)) {
            return 1;
        }
    }

    /* Uncompressed data */
    else {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_proc_compunit: Unit is not compressed\n");

        comp->uncomp_idx = 0;
        for (a = 0; a < comp_unit_size; a++) {
            ssize_t cnt;

            // Prevent an OOB write of comp->uncomp_buf
            if ((comp->uncomp_idx >= comp->buf_size_b) || (fs->block_size > comp->buf_size_b - comp->uncomp_idx)) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_READ);
                tsk_error_set_errstr("ntfs_proc_compunit: Buffer not big enough for uncompressed data (Index: %" PRIuSIZE ")", comp->uncomp_idx);
                return 1;
            }

            cnt =
                tsk_fs_read_block(fs, comp_unit[a],
                &comp->uncomp_buf[comp->uncomp_idx], fs->block_size);
            if (cnt != fs->block_size) {
                if (cnt >= 0) {
                    tsk_error_reset();
                    tsk_error_set_errno(TSK_ERR_FS_READ);
                }
                tsk_error_set_errstr2
                    ("ntfs_proc_compunit: Error reading block at %"
                    PRIuDADDR, comp_unit[a]);
                return 1;
            }
            comp->uncomp_idx += fs->block_size;
        }
    }
    return 0;
}



/**
 * Currently ignores the SPARSE flag
 */
static uint8_t
ntfs_attr_walk_special(
  const TSK_FS_ATTR * fs_attr,
  [[maybe_unused]] int flags,
  TSK_FS_FILE_WALK_CB a_action,
  void *ptr)
{
    TSK_FS_INFO *fs;
    NTFS_INFO *ntfs;

    // clean up any error messages that are lying around
    tsk_error_reset();
    if ((fs_attr == NULL) || (fs_attr->fs_file == NULL)
        || (fs_attr->fs_file->meta == NULL)
        || (fs_attr->fs_file->fs_info == NULL)) {
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr
            ("ntfs_attr_walk_special: Null arguments given\n");
        return 1;
    }

    fs = fs_attr->fs_file->fs_info;
    ntfs = (NTFS_INFO *) fs;

    /* Process the compressed buffer
     *
     * The compsize value equal to 0 can occur if we are processing an
     * isolated entry that is part of an attribute list.  The first
     * sequence of the attribute has the compsize and the latter ones
     * do not. So, if one of the non-base MFT entries is processed by
     * itself, we have that case.  I tried to assume it was 16, but it
     * caused decompression problems -- likely because this sequence
     * did not start on a compression unit boundary.  So, now we just
     * dump the compressed data instead of giving an error.
     */
    if (fs_attr->flags & TSK_FS_ATTR_COMP) {
        TSK_DADDR_T addr;
        TSK_FS_ATTR_RUN *fs_attr_run;
        TSK_DADDR_T *comp_unit;
        uint32_t comp_unit_idx = 0;
        NTFS_COMP_INFO comp;
        TSK_OFF_T off = 0;
        int retval;
        uint8_t stop_loop = 0;
        uint8_t init_size_reached = 0;
        uint8_t has_init_size = 0;

        if (fs_attr->nrd.compsize <= 0) {
            tsk_error_set_errno(TSK_ERR_FS_FWALK);
            tsk_error_set_errstr
                ("ntfs_attrwalk_special: Compressed attribute has compsize of 0 (%"
                PRIuINUM ")", fs_attr->fs_file->meta->addr);
            return 1;
        }

        /* Allocate the buffers and state structure */
        if (ntfs_uncompress_setup(fs, &comp, fs_attr->nrd.compsize)) {
            return 1;
        }

        comp_unit =
            (TSK_DADDR_T *) tsk_malloc(fs_attr->nrd.compsize *
            sizeof(TSK_DADDR_T));
        if (comp_unit == NULL) {
            ntfs_uncompress_done(&comp);
            return 1;
        }
        retval = TSK_WALK_CONT;

        if (fs_attr->nrd.initsize != fs_attr->fs_file->meta->size)
            has_init_size = 1;

        /* cycle through the number of runs we have */
        for (fs_attr_run = fs_attr->nrd.run; fs_attr_run;
            fs_attr_run = fs_attr_run->next) {
            size_t len_idx;

            /* We may get a FILLER entry at the beginning of the run
             * if we are processing a non-base file record since
             * this $DATA attribute could not be the first sequence in the
             * attribute. Therefore, do not error if it starts at 0 */
            if (fs_attr_run->flags & TSK_FS_ATTR_RUN_FLAG_FILLER) {
                if (fs_attr_run->addr != 0) {
                    tsk_error_reset();

                    if (fs_attr->fs_file->meta->
                        flags & TSK_FS_META_FLAG_UNALLOC)
                        tsk_error_set_errno(TSK_ERR_FS_RECOVER);
                    else
                        tsk_error_set_errno(TSK_ERR_FS_GENFS);
                    tsk_error_set_errstr
                        ("ntfs_attr_walk_special: Filler Entry exists in fs_attr_run %"
                        PRIuDADDR "@%" PRIuDADDR " - type: %" PRIu32
                        "  id: %d Meta: %" PRIuINUM " Status: %s",
                        fs_attr_run->len, fs_attr_run->addr, fs_attr->type,
                        fs_attr->id, fs_attr->fs_file->meta->addr,
                        (fs_attr->fs_file->meta->
                            flags & TSK_FS_META_FLAG_ALLOC) ? "Allocated" :
                        "Deleted");
                    free(comp_unit);
                    ntfs_uncompress_done(&comp);
                    return 1;
                }
                else {
                    if ((fs_attr_run->len > LLONG_MAX)
                        || (LLONG_MAX / fs_attr_run->len < fs->block_size)) {
                        if (fs_attr->fs_file->meta->
                            flags & TSK_FS_META_FLAG_UNALLOC)
                            tsk_error_set_errno(TSK_ERR_FS_RECOVER);
                        else
                            tsk_error_set_errno(TSK_ERR_FS_GENFS);
                        tsk_error_set_errstr
                            ("ntfs_attr_walk_special: Attribute run length is too large %"
                            PRIuDADDR "@%" PRIuDADDR " - type: %" PRIu32
                            "  id: %d Meta: %" PRIuINUM " Status: %s",
                            fs_attr_run->len, fs_attr_run->addr, fs_attr->type,
                            fs_attr->id, fs_attr->fs_file->meta->addr,
                            (fs_attr->fs_file->meta->
                                flags & TSK_FS_META_FLAG_ALLOC) ? "Allocated" :
                            "Deleted");
                        free(comp_unit);
                        ntfs_uncompress_done(&comp);
                        return 1;
                    }
                    off += (fs_attr_run->len * fs->block_size);
                    continue;
                }
            }
            addr = fs_attr_run->addr;

            /* cycle through each cluster in the run */
            for (len_idx = 0; len_idx < fs_attr_run->len; len_idx++) {

                if (addr > fs->last_block) {
                    tsk_error_reset();

                    if (fs_attr->fs_file->meta->
                        flags & TSK_FS_META_FLAG_UNALLOC)
                        tsk_error_set_errno(TSK_ERR_FS_RECOVER);
                    else
                        tsk_error_set_errno(TSK_ERR_FS_BLK_NUM);
                    tsk_error_set_errstr
                        ("ntfs_attr_walk_special: Invalid address in run (too large): %"
                        PRIuDADDR " Meta: %" PRIuINUM " Status: %s", addr,
                        fs_attr->fs_file->meta->addr,
                        (fs_attr->fs_file->meta->
                            flags & TSK_FS_META_FLAG_ALLOC) ? "Allocated" :
                        "Deleted");

                    free(comp_unit);
                    ntfs_uncompress_done(&comp);
                    return 1;
                }

                // queue up the addresses until we get a full unit
                comp_unit[comp_unit_idx++] = addr;

                // time to decompress (if queue is full or this is the last block)
                if ((comp_unit_idx == fs_attr->nrd.compsize)
                    || ((len_idx == fs_attr_run->len - 1)
                        && (fs_attr_run->next == NULL))) {
                    size_t i;


                    if (tsk_verbose)
                        tsk_fprintf(stderr,
                            "ntfs_proc_compunit: Decompressing at file offset %" PRIdOFF "\n", off);

                    // decompress the unit if we have not passed initsize yet.
                    if (!init_size_reached) {
                        if (ntfs_proc_compunit(ntfs, &comp, comp_unit,
                            comp_unit_idx)) {
                            tsk_error_set_errstr2("%" PRIuINUM " - type: %"
                                PRIu32 "  id: %d Status: %s",
                                fs_attr->fs_file->meta->addr, fs_attr->type,
                                fs_attr->id,
                                (fs_attr->fs_file->meta->
                                    flags & TSK_FS_META_FLAG_ALLOC) ?
                                "Allocated" : "Deleted");
                            free(comp_unit);
                            ntfs_uncompress_done(&comp);
                            return 1;
                        }

                        /* if we've passed the initialized size while reading this block,
                         * zero out the buffer beyond the initialized size. */
                        if (has_init_size && (off < fs_attr->nrd.initsize)) {
                            const int64_t prev_remanining_init_size = fs_attr->nrd.initsize - off;
                            if (prev_remanining_init_size < (int64_t)comp.buf_size_b) {
                                memset(&comp.uncomp_buf[prev_remanining_init_size], 0, comp.buf_size_b - prev_remanining_init_size);
                                init_size_reached = 1;
                            }
                        }
                    }
                    // set the buffers to 0s if we are past initsize
                    else {
                        ntfs_uncompress_reset(&comp);
                        comp.uncomp_idx = comp.buf_size_b;
                    }

                    // now call the callback with the uncompressed data
                    for (i = 0; i < comp_unit_idx; i++) {
                        int myflags;
                        size_t read_len;

                        myflags =
                            TSK_FS_BLOCK_FLAG_CONT |
                            TSK_FS_BLOCK_FLAG_COMP;
                        retval = is_clustalloc(ntfs, comp_unit[i]);
                        if (retval == -1) {
                            if (fs_attr->fs_file->meta->
                                flags & TSK_FS_META_FLAG_UNALLOC)
                                tsk_error_set_errno(TSK_ERR_FS_RECOVER);
                            free(comp_unit);
                            ntfs_uncompress_done(&comp);
                            return 1;
                        }
                        else if (retval == 1) {
                            myflags |= TSK_FS_BLOCK_FLAG_ALLOC;
                        }
                        else if (retval == 0) {
                            myflags |= TSK_FS_BLOCK_FLAG_UNALLOC;
                        }

                        // Unclear what the behavior should be here
                        // assuming POSIX like behavior is likely the required approach
                        if (off >= fs_attr->size)
                            read_len = 0;
                        else if (fs_attr->size - off > fs->block_size)
                            read_len = fs->block_size;
                        else
                            read_len = (size_t) (fs_attr->size - off);

                        if (i * fs->block_size + read_len >
                            comp.uncomp_idx) {
                            tsk_error_set_errno(TSK_ERR_FS_FWALK);
                            tsk_error_set_errstr
                                ("ntfs_attrwalk_special: Trying to read past end of uncompressed buffer: %"
                                PRIuSIZE " %" PRIuSIZE " Meta: %" PRIuINUM
                                " Status: %s",
                                i * fs->block_size + read_len,
                                comp.uncomp_idx,
                                fs_attr->fs_file->meta->addr,
                                (fs_attr->fs_file->meta->
                                    flags & TSK_FS_META_FLAG_ALLOC) ?
                                "Allocated" : "Deleted");
                            free(comp_unit);
                            ntfs_uncompress_done(&comp);
                            return 1;
                        }

                        // call the callback
                        retval =
                            a_action(fs_attr->fs_file, off, comp_unit[i],
                            &comp.uncomp_buf[i * fs->block_size], read_len,
                            (TSK_FS_BLOCK_FLAG_ENUM) myflags, ptr);

                        off += read_len;

                        if (off >= fs_attr->size) {
                            stop_loop = 1;
                            break;
                        }
                        if (retval != TSK_WALK_CONT) {
                            stop_loop = 1;
                            break;
                        }
                    }
                    comp_unit_idx = 0;
                }

                if (stop_loop)
                    break;

                /* If it is a sparse run, don't increment the addr so that
                 * it remains 0 */
                if (((fs_attr_run->flags & TSK_FS_ATTR_RUN_FLAG_SPARSE) ==
                        0)
                    && ((fs_attr_run->flags & TSK_FS_ATTR_RUN_FLAG_FILLER)
                        == 0))
                    addr++;
            }

            if (stop_loop)
                break;
        }

        ntfs_uncompress_done(&comp);
        free(comp_unit);

        if (retval == TSK_WALK_ERROR)
            return 1;
        else
            return 0;
    }
    else {
        tsk_error_set_errno(TSK_ERR_FS_FWALK);
        tsk_error_set_errstr
            ("ntfs_attrwalk_special: called with non-special attribute: %x",
            fs_attr->flags);
        return 1;
    }
}


/** \internal
 *
 * @returns number of bytes read or -1 on error (incl if offset is past EOF)
 */
static ssize_t
ntfs_file_read_special(const TSK_FS_ATTR * a_fs_attr,
    TSK_OFF_T a_offset, char *a_buf, size_t a_len)
{
    TSK_FS_INFO *fs = NULL;
    NTFS_INFO *ntfs = NULL;

    if ((a_fs_attr == NULL) || (a_fs_attr->fs_file == NULL)
        || (a_fs_attr->fs_file->meta == NULL)
        || (a_fs_attr->fs_file->fs_info == NULL)) {
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr
            ("ntfs_file_read_special: NULL parameters passed");
        return -1;
    }

    fs = a_fs_attr->fs_file->fs_info;
    ntfs = (NTFS_INFO *) fs;

    if (a_fs_attr->flags & TSK_FS_ATTR_COMP) {
        TSK_FS_ATTR_RUN *data_run_cur;
        TSK_OFF_T cu_blkoffset; // block offset of starting compression unit to start reading from
        size_t byteoffset;      // byte offset in compression unit of where we want to start reading from
        TSK_DADDR_T *comp_unit;
        uint32_t comp_unit_idx = 0;
        NTFS_COMP_INFO comp;
        size_t buf_idx = 0;
        uint8_t init_size_reached = 0;
        uint8_t has_init_size = 0;

        if (a_fs_attr->nrd.compsize <= 0) {
            tsk_error_set_errno(TSK_ERR_FS_FWALK);
            tsk_error_set_errstr
                ("ntfs_file_read_special: Compressed attribute has compsize of 0");
            return -1;
        }

        if (a_offset >= a_fs_attr->size) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_READ_OFF);
            tsk_error_set_errstr("ntfs_file_read_special - %" PRIdOFF
                " Meta: %" PRIuINUM, a_offset,
                a_fs_attr->fs_file->meta->addr);
            return -1;
        }

        // we return 0s for reads past the initsize
        if (a_offset >= a_fs_attr->nrd.initsize) {
            ssize_t len;

            if (tsk_verbose)
                fprintf(stderr,
                    "ntfs_file_read_special: Returning 0s for read past end of initsize (%"
                    PRIuINUM ")\n", a_fs_attr->fs_file->meta->addr);

            if (a_offset + (TSK_OFF_T)a_len > a_fs_attr->nrd.allocsize)
                len = (ssize_t) (a_fs_attr->nrd.allocsize - a_offset);
            else
                len = (ssize_t) a_len;
            memset(a_buf, 0, a_len);
            return len;
        }

        if (a_fs_attr->nrd.initsize != a_fs_attr->fs_file->meta->size)
            has_init_size = 1;

        /* Allocate the buffers and state structure */
        if (ntfs_uncompress_setup(fs, &comp, a_fs_attr->nrd.compsize)) {
            return -1;
        }

        comp_unit =
            (TSK_DADDR_T *) tsk_malloc(a_fs_attr->nrd.compsize *
            sizeof(TSK_DADDR_T));
        if (comp_unit == NULL) {
            ntfs_uncompress_done(&comp);
            return -1;
        }

        // figure out the needed offsets
        cu_blkoffset = a_offset / fs->block_size;
        if (cu_blkoffset) {
            cu_blkoffset /= a_fs_attr->nrd.compsize;
            cu_blkoffset *= a_fs_attr->nrd.compsize;
        }

        byteoffset = (size_t) (a_offset - cu_blkoffset * fs->block_size);

        // cycle through the run until we find where we can start to process the clusters
        for (data_run_cur = a_fs_attr->nrd.run;
            (data_run_cur) && (buf_idx < a_len);
            data_run_cur = data_run_cur->next) {

            TSK_DADDR_T addr;
            size_t a;

            // See if this run contains the starting offset they requested
            if (data_run_cur->offset + data_run_cur->len <
                (TSK_DADDR_T) cu_blkoffset)
                continue;


            // seek to the start of where we want to read (we may need to read several runs)
            if (data_run_cur->offset > (TSK_DADDR_T) cu_blkoffset)
                a = 0;
            else
                a = (size_t) (cu_blkoffset - data_run_cur->offset);

            addr = data_run_cur->addr;
            // don't increment addr if it is 0 -- sparse
            if (addr)
                addr += a;

            /* cycle through the relevant in the run */
            for (; a < data_run_cur->len && buf_idx < a_len; a++) {

                // queue up the addresses until we get a full unit
                comp_unit[comp_unit_idx++] = addr;

                // time to decompress (if queue is full or this is the last block)
                if ((comp_unit_idx == a_fs_attr->nrd.compsize)
                    || ((a == data_run_cur->len - 1)
                        && (data_run_cur->next == NULL))) {
                    size_t cpylen;

                    // decompress the unit if we are still in initsize
                    if (!init_size_reached) {
                        if (ntfs_proc_compunit(ntfs, &comp, comp_unit,
                            comp_unit_idx)) {
                            tsk_error_set_errstr2("%" PRIuINUM " - type: %"
                                PRIu32 "  id: %d  Status: %s",
                                a_fs_attr->fs_file->meta->addr,
                                a_fs_attr->type, a_fs_attr->id,
                                (a_fs_attr->fs_file->meta->
                                    flags & TSK_FS_META_FLAG_ALLOC) ?
                                "Allocated" : "Deleted");
                            free(comp_unit);
                            ntfs_uncompress_done(&comp);
                            return -1;
                        }

                        /* if we've passed the initialized size while reading this block,
                         * zero out the buffer beyond the initialized size
                         */
                        if (has_init_size) {
                            const int64_t remanining_init_size = a_fs_attr->nrd.initsize - buf_idx - a_offset;
                            if (remanining_init_size < (int64_t)comp.buf_size_b) {
                                memset(comp.uncomp_buf + remanining_init_size, 0, comp.buf_size_b - remanining_init_size);
                                init_size_reached = 1;
                            }
                        }
                    }
                    else {
                        ntfs_uncompress_reset(&comp);
                        comp.uncomp_idx = comp.buf_size_b;
                    }

                    // copy uncompressed data to the output buffer
                    if (comp.uncomp_idx < byteoffset) {

                        // @@ ERROR
                        free(comp_unit);
                        ntfs_uncompress_done(&comp);
                        return -1;
                    }
                    else if (comp.uncomp_idx - byteoffset <
                        a_len - buf_idx) {
                        cpylen = comp.uncomp_idx - byteoffset;
                    }
                    else {
                        cpylen = a_len - buf_idx;
                    }
                    // Make sure not to return more bytes than are in the file
                    if (cpylen > (a_fs_attr->size - (a_offset + buf_idx)))
                        cpylen =
                            (size_t) (a_fs_attr->size - (a_offset +
                                buf_idx));

                    memcpy(&a_buf[buf_idx], &comp.uncomp_buf[byteoffset],
                        cpylen);

                    // reset this in case we need to also read from the next run
                    byteoffset = 0;
                    buf_idx += cpylen;
                    comp_unit_idx = 0;

                }
                /* If it is a sparse run, don't increment the addr so that
                 * it remains 0 */
                if (((data_run_cur->flags & TSK_FS_ATTR_RUN_FLAG_SPARSE) ==
                        0)
                    && ((data_run_cur->flags & TSK_FS_ATTR_RUN_FLAG_FILLER)
                        == 0))
                    addr++;
            }
        }

        free(comp_unit);
        ntfs_uncompress_done(&comp);
        return (ssize_t) buf_idx;
    }
    else {
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr
            ("ntfs_file_read_special: called with non-special attribute: %x",
            a_fs_attr->flags);
        return -1;
    }
}


/* needs to be predefined for proc_attrseq */
static TSK_RETVAL_ENUM ntfs_proc_attrlist(NTFS_INFO *, TSK_FS_FILE *,
    const TSK_FS_ATTR *, TSK_STACK *);


/* This structure is used when processing attrlist attributes.
 * The Id part of the MFTNUM-TYPE-ID triple is unique only to a given
 * MFTNUM. With the case of attribute lists, a file may use multiple
 * MFT entires and therefore have multiple attributes with the same
 * type and id pair (if they are in different MFT entries). This map
 * is created by proc_attrlist when it assigns unique IDs to the
 * other entries.  proc_attrseq uses this when it adds the attributes.
 */
typedef struct {
    int num_used;
    TSK_INUM_T extMft[256];
    uint32_t type[256];
    uint32_t extId[256];
    uint8_t name[256][512];
    uint32_t newId[256];
} NTFS_ATTRLIST_MAP;

/*
 * Process an NTFS attribute sequence and load the data into data
 * structures.
 * An attribute sequence is a linked list of the attributes in an MFT entry.
 * This is called by copy_inode and proc_attrlist.
 *
 * @param ntfs File system to analyze
 * @param fs_file Generic metadata structure to add the attribute info to
 * @param attrseq Start of the attribute sequence to analyze
 * @param len Length of the attribute sequence buffer
 * @param a_attrinum MFT entry address that the attribute sequence came from (diff from fs_file for attribute lists)
 * @param a_attr_map List that maps to new IDs that were assigned by processing
 * the attribute list attribute (if it exists) or NULL if there is no attrlist.
 * @param a_seen_inum_list List of inums that have been previously processed based on attribute lists.
 *    Can be NULL when this is called for the first time. Should be non-NULL when this is called recursively by proc_attrlist.
 * @returns Error code
 */
static TSK_RETVAL_ENUM
ntfs_proc_attrseq(NTFS_INFO * ntfs,
    TSK_FS_FILE * fs_file, const ntfs_attr * a_attrseq, size_t len,
    TSK_INUM_T a_attrinum, const NTFS_ATTRLIST_MAP * a_attr_map, TSK_STACK * a_seen_inum_list)
{
    const ntfs_attr *attr;
    const TSK_FS_ATTR *fs_attr_attrl = NULL;
    char name[NTFS_MAXNAMLEN_UTF8 + 1];
    TSK_FS_INFO *fs = (TSK_FS_INFO *) & ntfs->fs_info;

    if (tsk_verbose)
        tsk_fprintf(stderr,
            "ntfs_proc_attrseq: Processing extended entry for primary entry %"
            PRIuINUM "\n", fs_file->meta->addr);

    if (fs_file->meta->attr == NULL) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("Null attribute list in ntfs_proc_attrseq");
        return TSK_ERR;
    }

    if (len > ntfs->mft_rsize_b) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("invalid length in ntfs_proc_attrseq");
        return TSK_ERR;
    }


    /* Cycle through the list of attributes
     * There are 16 bytes in the non-union part of
     * an ntfs_attr, so make sure there is at least room for that */
    for (attr = a_attrseq; ((uintptr_t) attr >= (uintptr_t) a_attrseq)
        && ((uintptr_t) attr + 16 <= ((uintptr_t) a_attrseq + len))
        && (tsk_getu32(fs->endian, attr->len) > 0
            && (tsk_getu32(fs->endian, attr->type) !=
                0xffffffff));
        attr =
        (ntfs_attr *) ((uintptr_t) attr + tsk_getu32(fs->endian,
                attr->len))) {

        int retVal, i;
        uint32_t type;
        uint16_t id, id_new;

        // sanity check on bounds of attribute. Prevents other
        // issues later on that use attr->len for bounds checks.
        if (((uintptr_t) attr + tsk_getu32(fs->endian,
                               attr->len)) > (uintptr_t)a_attrseq + len) {
            break;
        }

        // Ensure that the name offset doesn't refer to a location beyond
        // the attribute.
        uint16_t attr_name_off = tsk_getu16(fs->endian, attr->name_off);
        uint32_t attr_len = tsk_getu32(fs->endian, attr->len);
        // Note that it is valid for the name offset to be equal to the attribute length.
        if ((uint32_t) attr_name_off > attr_len) {
            break;
        }

        /* Get the type of this attribute */
        type = tsk_getu32(fs->endian, attr->type);
        id = tsk_getu16(fs->endian, attr->id);
        id_new = id;

        /* If the map was supplied, search through it to see if this
         * entry is in there.  Use that ID instead so that we always have
         * unique IDs for each attribute -- even if it spans multiple MFT entries. */
        if (a_attr_map) {
            if ((uint32_t) attr->nlen > (attr_len - (uint32_t) attr_name_off) / 2) {
                break;
            }
            for (i = 0; i < a_attr_map->num_used; i++) {
                if ((a_attr_map->type[i] == type) &&
                    (memcmp(a_attr_map->name[i],
                            (void *) ((uintptr_t) attr + attr_name_off),
                            attr->nlen * 2) == 0)) {
                    id_new = a_attr_map->newId[i];
                    break;
                }
            }
        }

        /* Copy the name and convert it to UTF8 */
        if (attr->nlen && ((uint32_t) attr->nlen * 2) < attr_len - attr_name_off) {
            int i;
            UTF8 *name8;
            UTF16 *name16;

            name8 = (UTF8 *) name;
            name16 = (UTF16 *) ((uintptr_t) attr + attr_name_off);

            retVal =
                tsk_UTF16toUTF8(fs->endian, (const UTF16 **) &name16,
                (UTF16 *) ((uintptr_t) name16 +
                    attr->nlen * 2),
                &name8,
                (UTF8 *) ((uintptr_t) name8 +
                    sizeof(name)), TSKlenientConversion);

            if (retVal != TSKconversionOK) {
                if (tsk_verbose)
                    tsk_fprintf(stderr,
                        "ntfs_proc_attrseq: Error converting NTFS attribute name to UTF8: %d %"
                        PRIuINUM, retVal, fs_file->meta->addr);
                *name = '\0';
            }

            /* Make sure it is NULL Terminated */
            else if ((uintptr_t) name8 >= (uintptr_t) name + sizeof(name))
                name[sizeof(name) - 1] = '\0';
            else
                *name8 = '\0';

            /* Clean up name */
            i = 0;
            while (name[i] != '\0') {
                if (TSK_IS_CNTRL(name[i]))
                    name[i] = '^';
                i++;
            }
        }
        else {
            name[0] = '\0';
        }

        /* For resident attributes, we will copy the buffer into
         * a TSK_FS_ATTR buffer, which is stored in the TSK_FS_META
         * structure
         */
        if (attr->res == NTFS_MFT_RES) {
            TSK_FS_ATTR *fs_attr;

            if (tsk_verbose)
                tsk_fprintf(stderr,
                    "ntfs_proc_attrseq: Resident Attribute in Type: %"
                    PRIu32 " Id: %" PRIu16 " IdNew: %" PRIu16
                    " Name: %s\n", type, id, id_new, name);

            /* Check that there is room for the data.
             * Resident data needs 24 bytes total */
            if (((uintptr_t)attr + 24) > ((uintptr_t)a_attrseq + len)) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_CORRUPT);
                tsk_error_set_errstr("ntfs_attr_walk: Resident attribute %"
                    PRIuINUM "-%" PRIu32
                    " starting offset and length too large",
                    fs_file->meta->addr, type);
                return TSK_COR;
            }

            /* Validate the offset lengths */
            if (((tsk_getu16(fs->endian,
                            attr->c.r.soff) + (uintptr_t) attr) >
                    ((uintptr_t) a_attrseq + len))
                || (((size_t)tsk_getu16(fs->endian,
                            attr->c.r.soff) + tsk_getu32(fs->endian,
                            attr->c.r.ssize) + (uintptr_t) attr) >
                    ((uintptr_t) a_attrseq + len))) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_CORRUPT);
                tsk_error_set_errstr("ntfs_attr_walk: Resident attribute %"
                    PRIuINUM "-%" PRIu32
                    " starting offset and length too large",
                    fs_file->meta->addr, type);
                return TSK_COR;
            }

            // Get a free fs_attr structure
            if ((fs_attr =
                    tsk_fs_attrlist_getnew(fs_file->meta->attr,
                        TSK_FS_ATTR_RES)) == NULL) {
                tsk_error_errstr2_concat(" - proc_attrseq");
                return TSK_ERR;
            }

            // set the details in the fs_attr structure
            if (tsk_fs_attr_set_str(fs_file, fs_attr, name,
                    (TSK_FS_ATTR_TYPE_ENUM) type,
                    id_new, (void *) ((uintptr_t) attr +
                        tsk_getu16(fs->endian,
                            attr->c.r.soff)), tsk_getu32(fs->endian,
                        attr->c.r.ssize))) {
                tsk_error_errstr2_concat("- proc_attrseq");
                return TSK_ERR;
            }

            // set the meta size if we find the relevant attribute
            if (TSK_FS_IS_DIR_META(fs_file->meta->type)
                && (type == NTFS_ATYPE_IDXROOT)) {
                fs_file->meta->size =
                    tsk_getu32(fs->endian, attr->c.r.ssize);
            }
            else if ((fs_file->meta->type == TSK_FS_META_TYPE_REG)
                && (type == NTFS_ATYPE_DATA) && (name[0] == '\0')) {
                fs_file->meta->size =
                    tsk_getu32(fs->endian, attr->c.r.ssize);
            }
        }

        /* For non-resident attributes, we will copy the runlist
         * to the generic form and then save it in the TSK_FS_META->attr
         * list
         */
        else {
            TSK_FS_ATTR *fs_attr = NULL;
            TSK_FS_ATTR_RUN *fs_attr_run = NULL;
            uint8_t data_flag = 0;
            uint32_t compsize = 0;
            TSK_RETVAL_ENUM retval;

            if (tsk_verbose)
                tsk_fprintf(stderr,
                    "ntfs_proc_attrseq: Non-Resident Attribute Type: %"
                    PRIu32 " Id: %" PRIu16 " IdNew: %" PRIu16
                    " Name: %s  Start VCN: %" PRIu64 "\n", type, id,
                    id_new, name, tsk_getu64(fs->endian,
                        attr->c.nr.start_vcn));

            /* Check that there is room for the data.
             * Non-resident data needs 64 bytes total */
            if (((uintptr_t)attr + 64) > ((uintptr_t)a_attrseq + len)) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_CORRUPT);
                tsk_error_set_errstr("ntfs_attr_walk: Non-Resident attribute %"
                    PRIuINUM "-%" PRIu32
                    " starting offset and length too large",
                    fs_file->meta->addr, type);
                return TSK_COR;
            }

            uint32_t attr_len = tsk_getu32(fs->endian, attr->len);
            uint64_t run_start_vcn = tsk_getu64(fs->endian, attr->c.nr.start_vcn);
            uint16_t run_off = tsk_getu16(fs->endian, attr->c.nr.run_off);

            // sanity check
            if ((run_off < 48) || (run_off >= attr_len)) {
                if (tsk_verbose)
                    tsk_fprintf(stderr, "ntfs_proc_attrseq: run offset out of bounds\n");
                break;
            }

            /* convert the run to generic form */
            retval = ntfs_make_data_run(ntfs,
                run_start_vcn,
                (ntfs_runlist *) ((uintptr_t) attr + run_off),
                attr_len - run_off,
                &fs_attr_run, NULL,
                a_attrinum);
            if (retval != TSK_OK) {
                tsk_error_errstr2_concat(" - proc_attrseq");
                return retval;
            }

            /* Determine the flags based on compression and stuff */
            data_flag = 0;
            if (tsk_getu16(fs->endian, attr->flags) & NTFS_ATTR_FLAG_COMP) {
                data_flag |= TSK_FS_ATTR_COMP;
                fs_file->meta->flags = (TSK_FS_META_FLAG_ENUM) (fs_file->meta->flags | TSK_FS_META_FLAG_COMP);
            }

            if (tsk_getu16(fs->endian, attr->flags) & NTFS_ATTR_FLAG_ENC)
                data_flag |= TSK_FS_ATTR_ENC;

            if (tsk_getu16(fs->endian, attr->flags) & NTFS_ATTR_FLAG_SPAR)
                data_flag |= TSK_FS_ATTR_SPARSE;

            /* SPECIAL CASE
             * We are in non-res section, so we know this
             * isn't $STD_INFO and $FNAME
             *
             * When we are processing a non-base entry, we may
             * find an attribute with an id of 0 and it is an
             * extension of a previous run (i.e. non-zero start VCN)
             *
             * We will lookup if we already have such an attribute
             * and get its ID
             *
             * We could also check for a start_vcn if this does
             * not fix the problem.
             *
             * NOTE: This should not be needed now that TSK assigns
             * unique ID values to the extended attributes.
             */
            if (id_new == 0) {
                int cnt, i;

                // cycle through the attributes
                cnt = tsk_fs_file_attr_getsize(fs_file);
                for (i = 0; i < cnt; i++) {

                    const TSK_FS_ATTR *fs_attr2 =
                        tsk_fs_file_attr_get_idx(fs_file, i);
                    if (!fs_attr2)
                        continue;

                    /* We found an attribute with the same name and type */
                    if (fs_attr2->type == type) {
                        if (((name[0] == '\0') && (fs_attr2->name == NULL))
                            || ((fs_attr2->name)
                                && (strcmp(fs_attr2->name, name) == 0))) {
                            id_new = fs_attr2->id;
                            if (tsk_verbose)
                                tsk_fprintf(stderr,
                                    "ntfs_proc_attrseq: Updating id from 0 to %"
                                    PRIu16 "\n", id_new);
                            break;
                        }
                    }
                }
            }

            /* the compression unit size is stored in the header
             * it is stored as the power of 2 (if it is not 0)
             */
            if (tsk_getu16(fs->endian, attr->c.nr.compusize) > 16) {
                /* 64k is the maximum compression unit size */
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_CORRUPT);
                tsk_error_set_errstr("ntfs_proc_attrseq: Compression unit size 2^%d too large",
                    tsk_getu16(fs->endian, attr->c.nr.compusize));
                if (fs_attr_run) {
                    tsk_fs_attr_run_free(fs_attr_run);
                    fs_attr_run = NULL;
                }
                return TSK_COR;
            }

            if (tsk_getu16(fs->endian, attr->c.nr.compusize) > 0) {
                compsize =
                    1 << (tsk_getu16(fs->endian, attr->c.nr.compusize));
            }
            else {
                compsize = 0;
                /* if this is 0, be sure to cancel out the COMP flag.
                 * This occurs when we process an extended attribute
                 * that has compressed data -- the attributes in the
                 * latter MFT entries do not have compsize set.
                 */
                if (data_flag & TSK_FS_ATTR_COMP) {
                    if (tsk_verbose)
                        fprintf(stderr,
                            "ntfs_proc_attrseq: Clearing compression setting for attribute %"
                            PRIuINUM "-%d because compsize is 0\n",
                            fs_file->meta->addr, type);
                    data_flag &= ~TSK_FS_ATTR_COMP;
                }
            }

            /* Add the run to the list */
            // see if this attribute has already been partially defined
            // @@@ This is bad design, we are casting away the const...
            fs_attr =
                (TSK_FS_ATTR *) tsk_fs_attrlist_get_id(fs_file->meta->attr,
                (TSK_FS_ATTR_TYPE_ENUM) type, id_new);
            if (fs_attr == NULL) {
                uint64_t ssize; // size
                uint64_t alen;  // allocated length

                if ((fs_attr =
                        tsk_fs_attrlist_getnew(fs_file->meta->attr,
                            TSK_FS_ATTR_RES)) == NULL) {
                    tsk_error_errstr2_concat(" - proc_attrseq: getnew");
                    // JRB: Coverity found leak.
                    if (fs_attr_run) {
                        tsk_fs_attr_run_free(fs_attr_run);
                        fs_attr_run = NULL;
                    }
                    return TSK_ERR;
                }

                ssize = tsk_getu64(fs->endian, attr->c.nr.ssize);
                /* This can happen with extended attributes, so
                 * we set it based on what we currently have.
                 * fs_attr_run can be NULL for $BadClust file. */
                if ((ssize == 0) && (fs_attr_run)) {
                    TSK_FS_ATTR_RUN *fs_attr_run_tmp;

                    ssize = fs_attr_run->offset * fs->block_size;
                    fs_attr_run_tmp = fs_attr_run;
                    while (fs_attr_run_tmp) {
                        ssize += (fs_attr_run_tmp->len * fs->block_size);
                        fs_attr_run_tmp = fs_attr_run_tmp->next;
                    }
                }

                // update the meta->size value if this is the default $Data attribute
                if ((fs_file->meta->type == TSK_FS_META_TYPE_REG)
                    && (type == NTFS_ATYPE_DATA) && (name[0] == '\0')) {
                    fs_file->meta->size = ssize;
                }

                alen = tsk_getu64(fs->endian, attr->c.nr.alen);
                /* This can also happen with extended attributes.
                 * set it to what we know about */
                if (alen == 0) {
                    alen = ssize;
                }

                if (tsk_fs_attr_set_run(fs_file, fs_attr,
                        fs_attr_run, name,
                        (TSK_FS_ATTR_TYPE_ENUM) type, id_new, ssize,
                        tsk_getu64(fs->endian, attr->c.nr.initsize),
                        alen, (TSK_FS_ATTR_FLAG_ENUM) data_flag, compsize)) {
                    tsk_error_errstr2_concat("- proc_attrseq: set run");

                    // If the run wasn't saved to the attribute, free it now
                    if (fs_attr_run && (fs_attr->nrd.run == NULL)) {
                        tsk_fs_attr_run_free(fs_attr_run);
                        fs_attr_run = NULL;
                    }
                    return TSK_COR;
                }
                // fs_file has taken over management of fs_attr_run
                fs_attr_run = NULL;

                // set the special functions
                if (fs_file->meta->flags & TSK_FS_META_FLAG_COMP) {
                    fs_attr->w = ntfs_attr_walk_special;
                    fs_attr->r = ntfs_file_read_special;
                }

            }
            else {
                if (tsk_fs_attr_add_run(fs, fs_attr, fs_attr_run)) {
                    tsk_error_errstr2_concat(" - proc_attrseq: put run");
                    if (fs_attr_run) {
                        tsk_fs_attr_run_free(fs_attr_run);
                        fs_attr_run = NULL;
                    }
                    return TSK_COR;
                }
            }
        }

        /*
         * Special Cases, where we grab additional information
         * regardless if they are resident or not
         */

        /* Standard Information (is always resident) */
        if (type == NTFS_ATYPE_SI) {
            uint32_t attr_len = tsk_getu32(fs->endian, attr->len);
            uint16_t attr_off = tsk_getu16(fs->endian, attr->c.r.soff);

            if (attr->res != NTFS_MFT_RES) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                    ("proc_attrseq: Standard Information Attribute is not resident!");
                return TSK_COR;
            }
            if ((attr_off < 16) || (attr_off >= attr_len)) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                    ("proc_attrseq: resident data offset of Standard Information Attribute is out of bounds!");
                return TSK_COR;
            }
            // A Standard Information Attribute can be 48 or 72 bytes in size (ntfs_attr_si is 72)
            if ((attr_len < 48) || (attr_off > attr_len - 48)) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                    ("proc_attrseq: resident data of Standard Information Attribute is too small!");
                return TSK_COR;
            }
            ntfs_attr_si *si = (ntfs_attr_si *) ((uintptr_t) attr + attr_off);

            fs_file->meta->mtime =
                nt2unixtime(tsk_getu64(fs->endian, si->mtime));
            fs_file->meta->mtime_nano =
                nt2nano(tsk_getu64(fs->endian, si->mtime));

            fs_file->meta->atime =
                nt2unixtime(tsk_getu64(fs->endian, si->atime));
            fs_file->meta->atime_nano =
                nt2nano(tsk_getu64(fs->endian, si->atime));

            fs_file->meta->ctime =
                nt2unixtime(tsk_getu64(fs->endian, si->ctime));
            fs_file->meta->ctime_nano =
                nt2nano(tsk_getu64(fs->endian, si->ctime));

            fs_file->meta->crtime =
                nt2unixtime(tsk_getu64(fs->endian, si->crtime));
            fs_file->meta->crtime_nano =
                nt2nano(tsk_getu64(fs->endian, si->crtime));

            fs_file->meta->uid = tsk_getu32(fs->endian, si->own_id);
            fs_file->meta->mode = (TSK_FS_META_MODE_ENUM)
                (fs_file->meta->mode | TSK_FS_META_MODE_IXUSR |
                 TSK_FS_META_MODE_IXGRP | TSK_FS_META_MODE_IXOTH);
            if ((tsk_getu32(fs->endian, si->dos) & NTFS_SI_RO) == 0)
                fs_file->meta->mode = (TSK_FS_META_MODE_ENUM)
                    (fs_file->meta->mode | TSK_FS_META_MODE_IRUSR |
                    TSK_FS_META_MODE_IRGRP | TSK_FS_META_MODE_IROTH);
            if ((tsk_getu32(fs->endian, si->dos) & NTFS_SI_HID) == 0)
                fs_file->meta->mode = (TSK_FS_META_MODE_ENUM)
                    (fs_file->meta->mode | TSK_FS_META_MODE_IWUSR |
                    TSK_FS_META_MODE_IWGRP | TSK_FS_META_MODE_IWOTH);
        }

        /* File Name (always resident) */
        else if (type == NTFS_ATYPE_FNAME) {
            uint32_t attr_len = tsk_getu32(fs->endian, attr->len);
            uint16_t attr_off = tsk_getu16(fs->endian, attr->c.r.soff);

            if (attr->res != NTFS_MFT_RES) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                    ("proc_attr_seq: File Name Attribute is not resident!");
                return TSK_COR;
            }
            if ((attr_off < 16) || (attr_off >= attr_len)) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                    ("proc_attrseq: resident data offset of File Name Attribute is out of bounds!");
                return TSK_COR;
            }
            // A File Name Attribute should be at least 66 bytes in size
            if ((attr_len < 66) || (attr_off > attr_len - 66)) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                    ("proc_attrseq: resident data of File Name Attribute is too small!");
                return TSK_COR;
            }
            ntfs_attr_fname *fname = (ntfs_attr_fname *) ((uintptr_t) attr + attr_off);
            if (fname->nspace == NTFS_FNAME_DOS) {
                continue;
            }

            fs_file->meta->time2.ntfs.fn_mtime =
                nt2unixtime(tsk_getu64(fs->endian, fname->mtime));
            fs_file->meta->time2.ntfs.fn_mtime_nano =
                nt2nano(tsk_getu64(fs->endian, fname->mtime));

            fs_file->meta->time2.ntfs.fn_atime =
                nt2unixtime(tsk_getu64(fs->endian, fname->atime));
            fs_file->meta->time2.ntfs.fn_atime_nano =
                nt2nano(tsk_getu64(fs->endian, fname->atime));

            fs_file->meta->time2.ntfs.fn_ctime =
                nt2unixtime(tsk_getu64(fs->endian, fname->ctime));
            fs_file->meta->time2.ntfs.fn_ctime_nano =
                nt2nano(tsk_getu64(fs->endian, fname->ctime));

            fs_file->meta->time2.ntfs.fn_crtime =
                nt2unixtime(tsk_getu64(fs->endian, fname->crtime));
            fs_file->meta->time2.ntfs.fn_crtime_nano =
                nt2nano(tsk_getu64(fs->endian, fname->crtime));

            fs_file->meta->time2.ntfs.fn_id = id;

            TSK_FS_META_NAME_LIST *fs_name;

            /* Seek to the end of the fs_name structures in TSK_FS_META */
            if (fs_file->meta->name2) {
                for (fs_name = fs_file->meta->name2;
                    (fs_name) && (fs_name->next != NULL);
                    fs_name = fs_name->next) {
                }

                /* add to the end of the existing list */
                fs_name->next = (TSK_FS_META_NAME_LIST *)
                    tsk_malloc(sizeof(TSK_FS_META_NAME_LIST));
                if (fs_name->next == NULL) {
                    return TSK_ERR;
                }
                fs_name = fs_name->next;
                fs_name->next = NULL;
            }
            else {
                /* First name, so we start a list */
                fs_file->meta->name2 = fs_name = (TSK_FS_META_NAME_LIST *)
                    tsk_malloc(sizeof(TSK_FS_META_NAME_LIST));
                if (fs_name == NULL) {
                    return TSK_ERR;
                }
                fs_name->next = NULL;
            }
            if (fname->nlen > attr_len - 66) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr
                    ("proc_attrseq: invalid name value size out of bounds!");
                return TSK_COR;
            }
            UTF16 *name16 = (UTF16 *) & fname->name;
            UTF8 *name8 = (UTF8 *) fs_name->name;

            retVal =
                tsk_UTF16toUTF8(fs->endian, (const UTF16 **) &name16,
                (UTF16 *) ((uintptr_t) name16 +
                    fname->nlen * 2),
                &name8,
                (UTF8 *) ((uintptr_t) name8 +
                    sizeof(fs_name->name)), TSKlenientConversion);
            if (retVal != TSKconversionOK) {
                if (tsk_verbose)
                    tsk_fprintf(stderr,
                        "proc_attr_seq: Error converting NTFS name in $FNAME to UTF8: %d",
                        retVal);
                *name8 = '\0';
            }
            /* Make sure it is NULL Terminated */
            else if ((uintptr_t) name8 >=
                (uintptr_t) fs_name->name + sizeof(fs_name->name))
                fs_name->name[sizeof(fs_name->name) - 1] = '\0';
            else
                *name8 = '\0';

            fs_name->par_inode = tsk_getu48(fs->endian, fname->par_ref);
            fs_name->par_seq = tsk_getu16(fs->endian, fname->par_seq);
        }

        /* If this is an attribute list than we need to process
         * it to get the list of other entries to read.  But, because
         * of the wierd scenario of the $MFT having an attribute list
         * and not knowing where the other MFT entires are yet, we wait
         * until the end of the attrseq to processes the list and then
         * we should have the $Data attribute loaded
         */
        else if (type == NTFS_ATYPE_ATTRLIST) {
            if (fs_attr_attrl) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_UNSUPFUNC);
                tsk_error_set_errstr
                    ("Multiple instances of attribute lists in the same MFT\n"
                    "I didn't realize that could happen, contact the developers");
                return TSK_ERR;
            }
            fs_attr_attrl = tsk_fs_attrlist_get_id(fs_file->meta->attr,
                (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_ATTRLIST, id_new);
            if (fs_attr_attrl == NULL) {
                tsk_error_errstr2_concat
                    ("- proc_attrseq: getting attribute list");
                return TSK_ERR;
            }
        }
    }


    /* Are we currently in the process of loading $MFT? */
    if (ntfs->loading_the_MFT == 1) {

        /* If we don't even have a mini cached version, get it now
         * Even if we are not done because of attribute lists, then we
         * should at least have the head of the list
         */
        if (!ntfs->mft_data) {
            int cnt, i;

            // cycle through the attributes
            cnt = tsk_fs_file_attr_getsize(fs_file);
            for (i = 0; i < cnt; i++) {
                const TSK_FS_ATTR *fs_attr =
                    tsk_fs_file_attr_get_idx(fs_file, i);
                if (!fs_attr)
                    continue;

                // get the default attribute
                if ((fs_attr->type == NTFS_ATYPE_DATA) &&
                    (fs_attr->name == NULL)) {
                    ntfs->mft_data = fs_attr;
                    break;
                }
            }

            // @@@ Is this needed here -- maybe it should be only in _open
            if (!ntfs->mft_data) {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_GENFS);
                tsk_error_set_errstr
                    ("$Data not found while loading the MFT");
                return TSK_ERR;
            }
        }

        /* Update the inode count based on the current size
         * IF $MFT has an attribute list, this value will increase each
         * time
         */
        fs->inum_count = ntfs->mft_data->size / ntfs->mft_rsize_b;
        fs->last_inum = fs->inum_count - 1;
    }

    /* If there was an attribute list, process it now, we wait because
     * the list can contain MFT entries that are described in $Data
     * of this MFT entry.  For example, part of the $DATA attribute
     * could follow the ATTRLIST entry, so we read it first and then
     * process the attribute list
     */
    if (fs_attr_attrl) {
    TSK_RETVAL_ENUM retval;
        if (a_seen_inum_list != NULL) {
            tsk_stack_push(a_seen_inum_list, a_attrinum);
        }
        if ((retval = ntfs_proc_attrlist(ntfs, fs_file, fs_attr_attrl, a_seen_inum_list)) != TSK_OK) {
            return retval;
        }
    }

    fs_file->meta->attr_state = TSK_FS_META_ATTR_STUDIED;
    return TSK_OK;
}



/********   Attribute List Action and Function ***********/



/*
 * Attribute lists are used when all of the attribute  headers can not
 * fit into one MFT entry.  This contains an entry for every attribute
 * and where they are located.  We process this to get the locations
 * and then call proc_attrseq on each of those, which adds the data
 * to the fs_file structure.
 *
 * @param ntfs File system being analyzed
 * @param fs_file Main file that will have attributes added to it.
 * @param fs_attr_attrlist Attrlist attribute that needs to be parsed.
 * @param a_seen_inum_list List of MFT entries (inums) previously
 * processed for this file or NULL.
 *
 * @returns status of error, corrupt, or OK
 */
static TSK_RETVAL_ENUM
ntfs_proc_attrlist(NTFS_INFO * ntfs,
    TSK_FS_FILE * fs_file, const TSK_FS_ATTR * fs_attr_attrlist, TSK_STACK * processed_inum_list)
{
    ntfs_attrlist *list;
    char *buf;
    uintptr_t endaddr;
    TSK_FS_INFO *fs = (TSK_FS_INFO *) & ntfs->fs_info;
    ntfs_mft *mft;
    TSK_FS_LOAD_FILE load_file;
    TSK_INUM_T mftToDo[256];
    uint16_t mftToDoCnt = 0;
    NTFS_ATTRLIST_MAP *map;
    uint16_t nextid = 0;
    TSK_STACK * mftSeenList = NULL;
    int a;

    if (tsk_verbose)
        tsk_fprintf(stderr,
            "ntfs_proc_attrlist: Processing entry %"
            PRIuINUM "\n", fs_file->meta->addr);

    if ((mft = (ntfs_mft *) tsk_malloc(ntfs->mft_rsize_b)) == NULL) {
        return TSK_ERR;
    }

    if ((map =
            (NTFS_ATTRLIST_MAP *) tsk_malloc(sizeof(NTFS_ATTRLIST_MAP))) ==
        NULL) {
        free(mft);
        return TSK_ERR;
    }

    /* Clear the contents of the todo buffer */
    memset(mftToDo, 0, sizeof(mftToDo));

    /* Get a copy of the attribute list stream using the above action */
    load_file.left = load_file.total = (size_t) fs_attr_attrlist->size;
    load_file.base = load_file.cur = buf =
        (char*) tsk_malloc((size_t) fs_attr_attrlist->size);
    if (buf == NULL) {
        free(mft);
        free(map);
        return TSK_ERR;
    }
    endaddr = (uintptr_t) buf + (uintptr_t) fs_attr_attrlist->size;
    if (tsk_fs_attr_walk(fs_attr_attrlist, TSK_FS_FILE_WALK_FLAG_NONE, tsk_fs_load_file_action,
            (void *) &load_file)) {
        tsk_error_errstr2_concat("- processing attrlist");
        free(mft);
        free(buf);
        free(map);
        return TSK_ERR;
    }

    /* this value should be zero, if not then we didn't read all of the
     * buffer
     */
    if (load_file.left > 0) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_FWALK);
        tsk_error_set_errstr2("processing attrlist of entry %" PRIuINUM,
            fs_file->meta->addr);
        free(mft);
        free(buf);
        free(map);
        return TSK_ERR;
    }

    /* The TSK design requires that each attribute have its own ID.
     * Therefore, we need to identify all of the unique attributes
     * so that we can assign a unique ID to them.
     * In this process, we will also identify the unique MFT entries to
     * process. */
    nextid = fs_attr_attrlist->id;      // we won't see this entry in the list
    for (list = (ntfs_attrlist *) buf;
        (list)
        // ntfs_attrlist contains the first byte of the name, which might actually be 0-length
        && (uintptr_t) list + sizeof(ntfs_attrlist) - 1 <= endaddr
        && tsk_getu16(fs->endian, list->len) > 0
        && (uintptr_t) list + tsk_getu16(fs->endian, list->len) <= endaddr
        && (uintptr_t) list + sizeof(ntfs_attrlist) - 1 + 2 * list->nlen <= endaddr;
        list =
        (ntfs_attrlist *) ((uintptr_t) list + tsk_getu16(fs->endian,
                list->len))) {
        uint8_t found;
        int i;

        TSK_INUM_T mftnum = tsk_getu48(fs->endian, list->file_ref);
        uint32_t type = tsk_getu32(fs->endian, list->type);
        uint16_t id = tsk_getu16(fs->endian, list->id);

        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_proc_attrlist: mft: %" PRIuINUM
                " type %" PRIu32 " id %" PRIu16
                "  VCN: %" PRIu64 "\n", mftnum, type,
                id, tsk_getu64(fs->endian, list->start_vcn));


        // keep track of the biggest ID that we saw.
        if (id > nextid)
            nextid = id;

        /* First identify the unique attributes.
         * we can have duplicate entries at different VCNs.  Ignore those. */
        found = 0;
        for (i = 0; i < map->num_used; i++) {
            if ((map->type[i] == type)
                && (memcmp(map->name[i], &list->name,
                        list->nlen * 2) == 0)) {
                found = 1;
                break;
            }
        }

        // add it to the list
        if (found == 0) {
            map->extMft[map->num_used] = mftnum;
            map->type[map->num_used] = type;
            map->extId[map->num_used] = id;
            memcpy(map->name[map->num_used], &list->name, list->nlen * 2);
            if (map->num_used < 255)
                map->num_used++;
        }

        /* also check the todo list -- skip the base entry
         * the goal here is to get a unique list of MFT entries
         * to later process. */
        if (mftnum != fs_file->meta->addr) {
            found = 0;
            for (i = 0; i < mftToDoCnt; i++) {
                if (mftToDo[i] == mftnum) {
                    found = 1;
                    break;
                }
            }
            if ((found == 0) && (mftToDoCnt < 256)) {
                mftToDo[mftToDoCnt++] = mftnum;
            }
        }
    }

    // update the map and assign unique IDs
    for (a = 0; a < map->num_used; a++) {
        // skip the base entry attributes -- they have unique attribute IDs
        if (map->extMft[a] == fs_file->meta->addr)
            continue;
        map->newId[a] = ++nextid;
    }


    /* Process the ToDo list & and call ntfs_proc_attr */
    for (a = 0; a < mftToDoCnt; a++) {
        TSK_RETVAL_ENUM retval;

        /* Sanity check. */
        if (mftToDo[a] < ntfs->fs_info.first_inum ||
            // decrement the last_inum because the last value is a special value for the ORPHANS directory
            mftToDo[a] > ntfs->fs_info.last_inum - 1 ||
            // MFT 0 is for $MFT.  We had one system that we got a reference to it from parsing an allocated attribute list
            mftToDo[a] == 0) {

            if (tsk_verbose) {
                /* this case can easily occur if the attribute list was non-resident and the cluster has been reallocated */

                tsk_fprintf(stderr,
                    "Invalid MFT file reference (%"
                    PRIuINUM
                    ") in the unallocated attribute list of MFT %"
                    PRIuINUM "", mftToDo[a], fs_file->meta->addr);
            }
            continue;
        }

        if ((retval =
                ntfs_dinode_lookup(ntfs, (char *) mft,
                    mftToDo[a], 0)) != TSK_OK) {
            // if the entry is corrupt, then continue
            if (retval == TSK_COR) {
                if (tsk_verbose)
                    tsk_error_print(stderr);
                tsk_error_reset();
                continue;
            }

            free(mft);
            free(map);
            free(buf);
            if (mftSeenList != NULL)
                tsk_stack_free(mftSeenList);
            tsk_error_errstr2_concat(" - proc_attrlist");
            return TSK_ERR;
        }

        /* verify that this entry refers to the original one */
        if (tsk_getu48(fs->endian, mft->base_ref) != fs_file->meta->addr) {

            /* Before we raise alarms, check if the original was
             * unallocated.  If so, then the list entry could
             * have been reallocated, so we will just ignore it
             */
            if (((tsk_getu16(fs->endian,
                            mft->flags) & NTFS_MFT_INUSE) == 0)
                || (fs_file->meta->flags & TSK_FS_META_FLAG_UNALLOC)) {
                continue;
            }
            else {
                tsk_error_reset();
                tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
                tsk_error_set_errstr("ntfs_proc_attrlist: MFT %" PRIuINUM
                    " is not an attribute list for %"
                    PRIuINUM
                    " (base file ref = %" PRIuINUM ")",
                    mftToDo[a],
                    fs_file->meta->addr,
                    tsk_getu48(fs->endian, mft->base_ref));
                free(mft);
                free(map);
                free(buf);
                if (mftSeenList != NULL)
                    tsk_stack_free(mftSeenList);
                return TSK_COR;
            }
        }

        // bounds check
        if (tsk_getu16(fs->endian, mft->attr_off) > ntfs->mft_rsize_b) {
            if (tsk_verbose)
                    tsk_fprintf(stderr, "ntfs_proc_attrlist: corrupt MFT entry attribute offsets\n");
            continue;
        }

        /* Process the attribute seq for this MFT entry and add them
         * to the TSK_FS_META structure
         */
        if (processed_inum_list != NULL && tsk_stack_find(processed_inum_list, mftToDo[a])) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_CORRUPT);
            tsk_error_set_errstr("ntfs_proc_attrlist: MFT %" PRIuINUM
                " seen in more than one attribute list for %"
                PRIuINUM
                " (base file ref = %" PRIuINUM ")",
                mftToDo[a],
                fs_file->meta->addr,
                tsk_getu48(fs->endian, mft->base_ref));
            free(mft);
            free(map);
            free(buf);
            if (mftSeenList != NULL)
                tsk_stack_free(mftSeenList);
            return TSK_COR;
        }

        if (processed_inum_list == NULL) {
            /*
             * Create a stack to keep track of inums already seen.
             * The local mftSeenList variable is used to keep track
             * of which iteration created the stack so that it can
             * be correctly freed later.
             */
            processed_inum_list = mftSeenList = tsk_stack_create();
        }

        if ((retval =
                ntfs_proc_attrseq(ntfs, fs_file, (ntfs_attr *) ((uintptr_t)
                        mft + tsk_getu16(fs->endian, mft->attr_off)),
                    ntfs->mft_rsize_b - tsk_getu16(fs->endian,
                        mft->attr_off), mftToDo[a], map, processed_inum_list)) != TSK_OK) {

            if (retval == TSK_COR) {
                if (tsk_verbose)
                    tsk_error_print(stderr);
                tsk_error_reset();
                continue;
            }
            tsk_error_errstr2_concat("- proc_attrlist");
            free(mft);
            free(map);
            free(buf);
            if (mftSeenList != NULL)
                tsk_stack_free(mftSeenList);
            return TSK_ERR;
        }
    }

    free(mft);
    free(map);
    free(buf);
    if (mftSeenList != NULL)
        tsk_stack_free(mftSeenList);
    return TSK_OK;
}



/**
 * Copy the MFT entry saved in a_buf to the generic structure.
 *
 * @param ntfs File system structure that contains entry to copy
 * @param fs_file Structure to copy processed data to.
 * @param a_buf MFT structure to copy from. Must be of size NTFS_INFO.mft_rsize_b
 * @param a_mnum MFT entry address
 *
 * @returns error code
 */
static TSK_RETVAL_ENUM
ntfs_dinode_copy(NTFS_INFO * ntfs, TSK_FS_FILE * a_fs_file, char *a_buf,
    TSK_INUM_T a_mnum)
{
    ntfs_attr *attr;
    TSK_FS_INFO *fs = (TSK_FS_INFO *) & ntfs->fs_info;
    TSK_RETVAL_ENUM retval;
    ntfs_mft *mft = (ntfs_mft *) a_buf;

    if ((a_fs_file == NULL) || (a_fs_file->meta == NULL)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("ntfs_dinode_copy: NULL fs_file given");
        return TSK_ERR;
    }

    /* if the attributes list has been used previously, then make sure the
     * flags are cleared
     */
    if (a_fs_file->meta->attr) {
        tsk_fs_attrlist_markunused(a_fs_file->meta->attr);
    }
    else {
        a_fs_file->meta->attr = tsk_fs_attrlist_alloc();
        if (a_fs_file->meta->attr == NULL)
            return TSK_ERR;
    }
    a_fs_file->meta->attr_state = TSK_FS_META_ATTR_EMPTY;

    /* If there are any name structures allocated, then free 'em */
    if (a_fs_file->meta->name2) {
        TSK_FS_META_NAME_LIST *fs_name1, *fs_name2;
        fs_name1 = a_fs_file->meta->name2;

        while (fs_name1) {
            fs_name2 = fs_name1->next;
            free(fs_name1);
            fs_name1 = fs_name2;
        }
        a_fs_file->meta->name2 = NULL;
    }

    /* Set the a_fs_file->meta values from mft */
    a_fs_file->meta->nlink = tsk_getu16(fs->endian, mft->link);
    a_fs_file->meta->seq = tsk_getu16(fs->endian, mft->seq);
    a_fs_file->meta->addr = a_mnum;

    /* Set the mode for file or directory */
    if (tsk_getu16(fs->endian, mft->flags) & NTFS_MFT_DIR)
        a_fs_file->meta->type = TSK_FS_META_TYPE_DIR;
    else
        a_fs_file->meta->type = TSK_FS_META_TYPE_REG;
    a_fs_file->meta->mode = TSK_FS_META_MODE_UNSPECIFIED;  // will be set by proc_attrseq

    /* the following will be changed once we find the correct attribute,
     * but initialize them now just in case
     */
    a_fs_file->meta->uid = 0;
    a_fs_file->meta->gid = 0;
    a_fs_file->meta->size = 0;
    a_fs_file->meta->mtime = 0;
    a_fs_file->meta->mtime_nano = 0;
    a_fs_file->meta->atime = 0;
    a_fs_file->meta->atime_nano = 0;
    a_fs_file->meta->ctime = 0;
    a_fs_file->meta->ctime_nano = 0;
    a_fs_file->meta->crtime = 0;
    a_fs_file->meta->crtime_nano = 0;
    a_fs_file->meta->time2.ntfs.fn_mtime = 0;
    a_fs_file->meta->time2.ntfs.fn_mtime_nano = 0;
    a_fs_file->meta->time2.ntfs.fn_atime = 0;
    a_fs_file->meta->time2.ntfs.fn_atime_nano = 0;
    a_fs_file->meta->time2.ntfs.fn_ctime = 0;
    a_fs_file->meta->time2.ntfs.fn_ctime_nano = 0;
    a_fs_file->meta->time2.ntfs.fn_crtime = 0;
    a_fs_file->meta->time2.ntfs.fn_crtime_nano = 0;
    a_fs_file->meta->time2.ntfs.fn_id = 0;

    /* add the flags */
    a_fs_file->meta->flags =
        ((tsk_getu16(fs->endian, mft->flags) &
            NTFS_MFT_INUSE) ? TSK_FS_META_FLAG_ALLOC :
        TSK_FS_META_FLAG_UNALLOC);


    /* Process the attribute sequence to fill in the fs_meta->attr
     * list and the other info such as size and times
     */
    if (tsk_getu16(fs->endian, mft->attr_off) > ntfs->mft_rsize_b) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("ntfs_dinode_copy: corrupt MFT entry attribute offsets");
        return TSK_ERR;
    }

    attr =
        (ntfs_attr *) ((uintptr_t) mft + tsk_getu16(fs->endian,
            mft->attr_off));
    if ((retval = ntfs_proc_attrseq(ntfs, a_fs_file, attr,
                ntfs->mft_rsize_b - tsk_getu16(fs->endian,
                    mft->attr_off), a_fs_file->meta->addr,
                NULL, NULL)) != TSK_OK) {
        return retval;
    }

    /* The entry has been 'used' if it has attributes */

    if ((a_fs_file->meta->attr == NULL)
        || (a_fs_file->meta->attr->head == NULL)
        || ((a_fs_file->meta->attr->head->flags & TSK_FS_ATTR_INUSE) == 0))
        a_fs_file->meta->flags = (TSK_FS_META_FLAG_ENUM) (a_fs_file->meta->flags | TSK_FS_META_FLAG_UNUSED);
    else
        a_fs_file->meta->flags = (TSK_FS_META_FLAG_ENUM) (a_fs_file->meta->flags | TSK_FS_META_FLAG_USED);

    return TSK_OK;
}



/** \internal
 * Load the attributes.  In NTFS, the attributes are already loaded
 * so return error values based on current state.
 * @param a_fs_file File to load attributes for.
 * @returns 1 on error
 */
static uint8_t
ntfs_load_attrs(TSK_FS_FILE * a_fs_file)
{
    if ((a_fs_file == NULL) || (a_fs_file->meta == NULL)) {
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("ntfs_load_attrs: called with NULL pointers");
        return 1;
    }

    /* Verify the file has attributes */
    if (a_fs_file->meta->attr == NULL) {
        if (a_fs_file->meta->flags & TSK_FS_META_FLAG_UNALLOC)
            tsk_error_set_errno(TSK_ERR_FS_RECOVER);
        else
            tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("ntfs_load_attrs: attributes are NULL");
        return 1;
    }
    return 0;
}

/**
 * Read an MFT entry and save it in the generic TSK_FS_META format.
 *
 * @param fs File system to read from.
 * @param mftnum Address of mft entry to read
 * @returns 1 on error
 */
static uint8_t
ntfs_inode_lookup(TSK_FS_INFO * fs, TSK_FS_FILE * a_fs_file,
    TSK_INUM_T mftnum)
{
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;
    char *mft;
    uint8_t allocedMeta = 0;

    // clean up any error messages that are lying around
    tsk_error_reset();

    if (a_fs_file == NULL) {
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("ntfs_inode_lookup: fs_file is NULL");
        return 1;
    }

    if (a_fs_file->meta == NULL) {
        a_fs_file->meta = tsk_fs_meta_alloc(NTFS_FILE_CONTENT_LEN);
        if (a_fs_file->meta == NULL)
            return 1;
        allocedMeta = 1;
    }
    else {
        tsk_fs_meta_reset(a_fs_file->meta);
    }

    // see if they are looking for the special "orphans" directory
    if (mftnum == TSK_FS_ORPHANDIR_INUM(fs)) {
        if (tsk_fs_dir_make_orphan_dir_meta(fs, a_fs_file->meta))
            return 1;
        else
            return 0;
    }

    if ((mft = (char *) tsk_malloc(ntfs->mft_rsize_b)) == NULL) {
        return 1;
    }

    /* Lookup inode and store it in the ntfs structure */
    if (ntfs_dinode_lookup(ntfs, mft, mftnum, & (a_fs_file->meta->start_of_inode)) != TSK_OK) {
        free(mft);
        return 1;
    }

    /* Copy the structure in ntfs to generic a_fs_file->meta */
    if (ntfs_dinode_copy(ntfs, a_fs_file, mft, mftnum) != TSK_OK) {
        free(mft);
        return 1;
    }

    /* Check if the metadata is the same sequence as the name - if it was already set.
     * Note that this is not as efficient and elegant as desired, but works for now.
     * Better design would be to pass sequence into dinode_lookup and have a more
     * obvious way to pass the desired sequence in.  fs_dir_walk_lcl sets the name
     * before calling this, which motivated this quick fix. */
    if ((a_fs_file->name != NULL) && (a_fs_file->name->meta_addr == mftnum)) {

        /* NTFS Updates the sequence when an entry is deleted and not when
         * it is allocated.  So, if we have a deleted MFT entry, then use
         * its previous sequence number to compare with the name so that we
         * still match them up (until the entry is allocated again). */
        uint16_t seqToCmp = a_fs_file->meta->seq;
        if (a_fs_file->meta->flags & TSK_FS_META_FLAG_UNALLOC) {
            if (a_fs_file->meta->seq > 0)
                seqToCmp--;
        }

        if (a_fs_file->name->meta_seq != seqToCmp) {
            if (allocedMeta) {
                tsk_fs_meta_close(a_fs_file->meta);
                a_fs_file->meta = NULL;
            }
            else {
                tsk_fs_meta_reset(a_fs_file->meta);
            }
        }
    }

    free(mft);
    return 0;
}




/**********************************************************************
 *
 *  Load special MFT structures into the NTFS_INFO structure
 *
 **********************************************************************/

/* The attrdef structure defines the types of attributes and gives a
 * name value to the type number.
 *
 * We currently do not use this during the analysis (Because it has not
 * historically changed, but we do display it in fsstat
 *
 * Return 1 on error and 0 on success
 */
static uint8_t
ntfs_load_attrdef(NTFS_INFO * ntfs)
{
    const TSK_FS_ATTR *fs_attr;
    TSK_FS_INFO *fs = &ntfs->fs_info;
    TSK_FS_LOAD_FILE load_file;

    /* if already loaded, return now */
    if (ntfs->attrdef)
        return 1;

    std::unique_ptr<TSK_FS_FILE, decltype(&tsk_fs_file_close)> fs_file{
        tsk_fs_file_open_meta(fs, NULL, NTFS_MFT_ATTR),
        tsk_fs_file_close
    };

    if (!fs_file)
        return 1;

    fs_attr = tsk_fs_attrlist_get(fs_file->meta->attr, (TSK_FS_ATTR_TYPE_ENUM
) NTFS_ATYPE_DATA);
    if (!fs_attr) {
        //("Data attribute not found in $Attr");
        return 1;
    }

// @@@ We need to do a sanity check on the size of fs_attr->size

    /* Get a copy of the attribute list stream using the above action */
    load_file.left = load_file.total = (size_t) fs_attr->size;
    load_file.base = load_file.cur = (char*) tsk_malloc((size_t) fs_attr->size);
    if (load_file.cur == NULL) {
        return 1;
    }
    ntfs->attrdef = (ntfs_attrdef *) load_file.base;

    if (tsk_fs_attr_walk(fs_attr,
            TSK_FS_FILE_WALK_FLAG_NONE, tsk_fs_load_file_action, (void *) &load_file)) {
        tsk_error_errstr2_concat(" - load_attrdef");
        free(ntfs->attrdef);
        ntfs->attrdef = NULL;
        return 1;
    }
    else if (load_file.left > 0) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_FWALK);
        tsk_error_set_errstr
            ("load_attrdef: space still left after walking $Attr data");
        free(ntfs->attrdef);
        ntfs->attrdef = NULL;
        return 1;
    }

    ntfs->attrdef_len = (size_t) fs_attr->size;
    return 0;
}


/*
 * return the name of the attribute type.  If the attribute has not
 * been loaded yet, it will be.
 *
 * Return 1 on error and 0 on success
 */
uint8_t
ntfs_attrname_lookup(TSK_FS_INFO * fs, uint16_t type, char *name, int len)
{
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;
    ntfs_attrdef *attrdef;
    if (!ntfs->attrdef) {
        if (ntfs_load_attrdef(ntfs))
            return 1;
    }

    attrdef = ntfs->attrdef;
    while (
        (((uintptr_t) attrdef - (uintptr_t) ntfs->attrdef +
                sizeof(ntfs_attrdef)) < ntfs->attrdef_len) &&
        (tsk_getu32(fs->endian, attrdef->type))) {
        if (tsk_getu32(fs->endian, attrdef->type) == type) {

            UTF16 *name16 = (UTF16 *) attrdef->label;
            UTF8 *name8 = (UTF8 *) name;
            int retVal;
            retVal =
                tsk_UTF16toUTF8(fs->endian, (const UTF16 **) &name16,
                (UTF16 *) ((uintptr_t) name16 +
                    sizeof(attrdef->label)),
                &name8,
                (UTF8 *) ((uintptr_t) name8 + len), TSKlenientConversion);
            if (retVal != TSKconversionOK) {
                if (tsk_verbose)
                    tsk_fprintf(stderr,
                        "attrname_lookup: Error converting NTFS attribute def label to UTF8: %d",
                        retVal);
                break;
            }

            /* Make sure it is NULL Terminated */
            else if ((uintptr_t) name8 >= (uintptr_t) name + len)
                name[len - 1] = '\0';
            else
                *name8 = '\0';
            return 0;
        }
        attrdef++;
    }
    /* If we didn't find it, then call it '?' */
    snprintf(name, len, "?");
    return 0;
}


/* Load the block bitmap $Data run  and allocate a buffer for a cache
 *
 * return 1 on error and 0 on success
 * */
static uint8_t
ntfs_load_bmap(NTFS_INFO * ntfs)
{
    ssize_t cnt = 0;
    ntfs_attr *attr = NULL;
    ntfs_attr *data_attr = NULL;
    TSK_FS_INFO *fs = NULL;
    ntfs_mft *mft = NULL;

    uint32_t attr_len = 0;
    uint32_t attr_type = 0;

    uint64_t run_start_vcn;
    uint16_t run_off;

    if (ntfs == NULL) {
        goto on_error;
    }
    fs = &ntfs->fs_info;

    if ((mft = (ntfs_mft *) tsk_malloc(ntfs->mft_rsize_b)) == NULL) {
        goto on_error;
    }

    /* Get data on the bitmap */
    if (ntfs_dinode_lookup(ntfs, (char *) mft, NTFS_MFT_BMAP, 0) != TSK_OK) {
        goto on_error;
    }

    attr = (ntfs_attr *) ((uintptr_t) mft +
        tsk_getu16(fs->endian, mft->attr_off));
    data_attr = NULL;

    /* cycle through them */
    while ((uintptr_t) attr + sizeof (ntfs_attr) <=
            ((uintptr_t) mft + (uintptr_t) ntfs->mft_rsize_b)) {

        attr_len = tsk_getu32(fs->endian, attr->len);
        attr_type = tsk_getu32(fs->endian, attr->type);

        if ((attr_len == 0) || (attr_type == 0xffffffff)) {
            break;
        }

        if (attr_type == NTFS_ATYPE_DATA) {
            data_attr = attr;
            break;
        }

        attr = (ntfs_attr *) ((uintptr_t) attr + attr_len);
    }

    /* did we get it? */
    if (data_attr == NULL) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr("Error Finding Bitmap Data Attribute");
        goto on_error;
    }
    attr_len = tsk_getu32(fs->endian, data_attr->len);
    if (attr_len > ntfs->mft_rsize_b) {
        goto on_error;
    }

    run_start_vcn = tsk_getu64(fs->endian, data_attr->c.nr.start_vcn);
    run_off = tsk_getu16(fs->endian, data_attr->c.nr.run_off);

    if ((run_off < 48) ||
        (run_off >= attr_len) ||
        ((uintptr_t) data_attr + run_off) >= ((uintptr_t) mft + (uintptr_t) ntfs->mft_rsize_b)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr("Invalid run_off of Bitmap Data Attribute - value out of bounds");
        goto on_error;
    }
    /* convert data run to generic form */
    if ((ntfs_make_data_run(ntfs,
                run_start_vcn,
                (ntfs_runlist *) ((uintptr_t) data_attr + run_off),
                attr_len - run_off,
                &(ntfs->bmap), NULL, NTFS_MFT_BMAP)) != TSK_OK) {
        goto on_error;
    }
    ntfs->bmap_buf = (char *) tsk_malloc(fs->block_size);
    if (ntfs->bmap_buf == NULL) {
        goto on_error;
    }

    /* Load the first cluster so that we have something there */
    ntfs->bmap_buf_off = 0;

    // Check ntfs->bmap before it is accessed.
    if (ntfs->bmap == NULL) {
        goto on_error;
    }
    if (ntfs->bmap->addr > fs->last_block) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_GENFS);
        tsk_error_set_errstr
            ("ntfs_load_bmap: Bitmap too large for image size: %" PRIuDADDR
            "", ntfs->bmap->addr);
        goto on_error;
    }
    cnt =
        tsk_fs_read_block(fs,
        ntfs->bmap->addr, ntfs->bmap_buf, fs->block_size);
    if (cnt != fs->block_size) {
        if (cnt >= 0) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_READ);
        }
        tsk_error_set_errstr2("ntfs_load_bmap: Error reading block at %"
            PRIuDADDR, ntfs->bmap->addr);
        goto on_error;
    }

    free (mft);
    return 0;

on_error:
    if (mft != NULL) {
        free (mft);
    }
    return 1;
}


/*
 * Load the VOLUME MFT entry and the VINFO attribute so that we
 * can identify the volume version of this.
 *
 * Return 1 on error and 0 on success
 */
static uint8_t
ntfs_load_ver(NTFS_INFO * ntfs)
{
    TSK_FS_INFO *fs = (TSK_FS_INFO *) & ntfs->fs_info;
    const TSK_FS_ATTR *fs_attr;

    std::unique_ptr<TSK_FS_FILE, decltype(&tsk_fs_file_close)> fs_file{
        tsk_fs_file_open_meta(fs, NULL, NTFS_MFT_VOL),
        tsk_fs_file_close
    };

    if (!fs_file) {
        return 1;
    }

    /* cache the data attribute */
    fs_attr = tsk_fs_attrlist_get(fs_file->meta->attr, (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_VINFO);
    if (!fs_attr) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr("Volume Info attribute not found in $Volume");
        return 1;
    }

    if ((fs_attr->flags & TSK_FS_ATTR_RES)
        && (fs_attr->size)) {
        ntfs_attr_vinfo *vinfo = (ntfs_attr_vinfo *) fs_attr->rd.buf;

        if ((vinfo->maj_ver == 1)
            && (vinfo->min_ver == 2)) {
            ntfs->ver = NTFS_VINFO_NT;
        }
        else if ((vinfo->maj_ver == 3)
            && (vinfo->min_ver == 0)) {
            ntfs->ver = NTFS_VINFO_2K;
        }
        else if ((vinfo->maj_ver == 3)
            && (vinfo->min_ver == 1)) {
            ntfs->ver = NTFS_VINFO_XP;
        }
        else {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_GENFS);
            tsk_error_set_errstr("unknown version: %d.%d\n",
                vinfo->maj_ver, vinfo->min_ver);
            return 1;
        }
    }
    else {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_GENFS);
        tsk_error_set_errstr
            ("load_version: VINFO is a non-resident attribute");
        return 1;
    }

    return 0;
}


#if TSK_USE_SID
/** \internal
 * Prints the value of sds into the a_sidstr string in ASCII form.  This will allocate a new buffer for the
 * string, so a_sidstr should not point to a buffer. Output is in format of:
 * S-R-I-S-S... with 'R' being revision, 'I' being the identifier authority, and 'S' being subauthority values.
 *
 * @param a_fs File system
 * @param a_sds SDS
 * @param a_sidstr [out] Pointer that will be assigned to the buffer allocated by this function to store the string.
 * @returns 1 on error, 0 on success
 */
static uint8_t
ntfs_sds_to_str(TSK_FS_INFO * a_fs, const ntfs_attr_sds * a_sds,
    char **a_sidstr)
{
    ntfs_sid *sid = NULL;

    uint32_t owner_offset;
    *a_sidstr = NULL;

    if ((a_fs == NULL) || (a_sds == NULL) || (a_sidstr == NULL)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("Invalid argument");
        return 1;
    }

    owner_offset =
        tsk_getu32(a_fs->endian, a_sds->self_rel_sec_desc.owner);

    if (((uintptr_t) & a_sds->self_rel_sec_desc + owner_offset) >
        ((uintptr_t) a_sds + tsk_getu32(a_fs->endian, a_sds->ent_size))) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr
            ("ntfs_sds_to_str: owner offset larger than a_sds length");
        return 1;
    }

    sid =
        (ntfs_sid *) ((uint8_t *) & a_sds->self_rel_sec_desc +
        owner_offset);

    //tsk_fprintf(stderr, "Revision: %i\n", sid->revision);

    // This check helps not process invalid data, which was noticed while testing
    // a failing harddrive
    if (sid->revision == 1) {
        uint64_t authority = 0;
        int i, len;
        char *sid_str_offset = NULL;
        char *sid_str = NULL;

        //tsk_fprintf(stderr, "Sub-Authority Count: %i\n", sid->sub_auth_count);
        authority = 0;
        for (i = 0; i < 6; i++)
            authority += (uint64_t) sid->ident_auth[i] << ((5 - i) * 8);

        //tsk_fprintf(stderr, "NT Authority: %" PRIu64 "\n", authority);

        // "S-1-AUTH-SUBAUTH-SUBAUTH..."
        const size_t sid_str_len = 4 + 13 + (1 + 10) * sid->sub_auth_count;

        // Allocate the buffer for the string representation of the SID.
        if ((sid_str = (char *) tsk_malloc(sid_str_len + 1)) == NULL) {
            return 1;
        }

        len = snprintf(sid_str, sid_str_len + 1, "S-1-%" PRIu64, authority);
        sid_str_offset = sid_str + len;

        for (i = 0; i < sid->sub_auth_count; i++) {
            len = snprintf(sid_str_offset, sid_str_len + 1 - len, "-%" PRIu32, sid->sub_auth[i]);
            sid_str_offset += len;
        }
        *a_sidstr = sid_str;
        //tsk_fprintf(stderr, "SID: %s\n", sid_str);
    }
    else {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_GENFS);
        tsk_error_set_errstr("ntfs_sds_to_str: Invalid SID revision (%d)",
            sid->revision);
        return 1;               // Invalid revision number in the SID.
    }

    return 0;
}




/** \internal
 * Maps a security id value from a file to its SDS structure
 *
 * Note: This routine assumes &ntfs->sid_lock is locked by the caller.
 *
 * @param fs File system
 * @param secid Security Id to find SDS for.
 * @returns NULL on error
 */
static const ntfs_attr_sds *
ntfs_get_sds(TSK_FS_INFO * fs, uint32_t secid)
{
    uint32_t i = 0;
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;
    ntfs_attr_sii *sii = NULL;
    ntfs_attr_sds *sds = NULL;
    uint32_t sii_secid = 0;
    uint32_t sds_secid = 0;
    uint32_t sii_sechash = 0;
    uint32_t sds_sechash = 0;
    uint64_t sds_file_off = 0;
    //uint32_t sds_ent_size = 0;
    uint64_t sii_sds_file_off = 0;
    uint32_t sii_sds_ent_size = 0;

    if ((fs == NULL) || (secid == 0)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("Invalid argument");
        return NULL;
    }

    // Loop through all the SII entries looking for the security id matching that found in the file.
    // This lookup is obviously O(n^2) for all n files. However, since so many files have the exact
    // same security identifier, it is not really that bad. In reality, 100,000 files may only map to
    // 10,000 security identifiers. Since SII entries are 0x28 bytes each and security identifiers
    // increase incrementally, we could go directly to the entry in question ((secid * 0x28) + 256).
    // SII entries started at 256 on Vista; however, I did not look at the starting secid for other
    // versions of NTFS.
  //
  // It appears that the file format may have changed since this was first written. There now appear to
  // be multiple entries for each security ID. Some may no longer be valid, so we loop over all of them
  // until we find one that looks valid.
  for (i = 0; i < ntfs->sii_data.used; i++) {
    if (! (tsk_getu32(fs->endian,
      ((ntfs_attr_sii *)(ntfs->sii_data.buffer))[i].key_sec_id) == secid)) {
      continue;
    }

    // We found a potentially good SII entry
    sii = &((ntfs_attr_sii *)(ntfs->sii_data.buffer))[i];
    sii_secid = tsk_getu32(fs->endian, sii->key_sec_id);
    sii_sechash = tsk_getu32(fs->endian, sii->data_hash_sec_desc);
    sii_sds_file_off = tsk_getu64(fs->endian, sii->sec_desc_off);
    sii_sds_ent_size = tsk_getu32(fs->endian, sii->sec_desc_size);

    // Check that we do not go out of bounds.
    if (sii_sds_file_off > ntfs->sds_data.size) {
      tsk_error_reset();
      tsk_error_set_errno(TSK_ERR_FS_GENFS);
      tsk_error_set_errstr("ntfs_get_sds: SII offset too large (%" PRIu64
        ")", sii_sds_file_off);
      continue;
    }
    else if (!sii_sds_ent_size) {
      tsk_error_reset();
      tsk_error_set_errno(TSK_ERR_FS_GENFS);
      tsk_error_set_errstr("ntfs_get_sds: SII entry size is invalid (%"
        PRIu32 ")", sii_sds_ent_size);
      continue;
    }

    sds =
      (ntfs_attr_sds *)((uint8_t *)ntfs->sds_data.buffer +
        sii_sds_file_off);
    sds_secid = tsk_getu32(fs->endian, sds->sec_id);
    sds_sechash = tsk_getu32(fs->endian, sds->hash_sec_desc);
    sds_file_off = tsk_getu64(fs->endian, sds->file_off);

    // Sanity check to make sure the $SII entry points to
    // the correct $SDS entry.
    if ((sds_secid == sii_secid) &&
      (sds_sechash == sii_sechash) && (sds_file_off == sii_sds_file_off)
      //&& (sds_ent_size == sii_sds_ent_size)
      ) {
      // Clear any previous errors
      tsk_error_reset();
      return sds;
    }
    tsk_error_reset();
    tsk_error_set_errno(TSK_ERR_FS_GENFS);
    tsk_error_set_errstr("ntfs_get_sds: SII entry %" PRIu32 " not found", sii_secid);
  }

  // If we never even found an SII entry that matched our secid, update the error state.
  // Otherwise leave it as the last error recorded.
  if (sii == NULL) {
    tsk_error_reset();
    tsk_error_set_errno(TSK_ERR_FS_GENFS);
    tsk_error_set_errstr("ntfs_get_sds: Got to end w/out data");
  }
    return NULL;
}
#endif

/** \internal
 * NTFS-specific function (pointed to in FS_INFO) that maps a security ID
 * to an ASCII printable string.
 * Read the contents of the STANDARD_INFORMATION attribute of a file
 * to get the security id. Once we have the security id, we will
 * search $Secure:$SII to find a matching security id. That $SII entry
 * will contain the offset within the $SDS stream for the $SDS entry,
 * which contains the owner SID
 *
 * @param a_fs_file File to get security info on
 * @param sid_str [out] location where string representation of security info will be stored.
 Caller must free the string.
 * @returns 1 on error
 */
static uint8_t
ntfs_file_get_sidstr(TSK_FS_FILE * a_fs_file, char **sid_str)
{
#if TSK_USE_SID
    const TSK_FS_ATTR *fs_data;
    ntfs_attr_si *si;
    const ntfs_attr_sds *sds;
    NTFS_INFO *ntfs = (NTFS_INFO *) a_fs_file->fs_info;

    *sid_str = NULL;

    if (!a_fs_file->meta->attr) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_GENFS);
    tsk_error_set_errstr
    ("ntfs_file_get_sidstr: file argument has no meta data");
        return 1;
    }

    // Read STANDARD_INFORMATION attribute for the security id of the file.
    fs_data = tsk_fs_attrlist_get(a_fs_file->meta->attr,
        TSK_FS_ATTR_TYPE_NTFS_SI);
    if (!fs_data) {
        tsk_error_set_errstr2("- ntfs_file_get_sidstr:SI attribute");
        return 1;
    }

    si = (ntfs_attr_si *) fs_data->rd.buf;
    if (!si) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_GENFS);
        tsk_error_set_errstr("ntfs_file_get_sidstr: SI buf is NULL");
        return 1;
    }

    tsk_take_lock(&ntfs->sid_lock);
    // sds points inside ntfs->sds_data, which we've just locked
    sds =
        ntfs_get_sds(a_fs_file->fs_info,
        tsk_getu32(a_fs_file->fs_info->endian, si->sec_id));
    if (!sds) {
        tsk_release_lock(&ntfs->sid_lock);
        tsk_error_set_errstr2("- ntfs_file_get_sidstr:SI attribute");
        return 1;
    }
    if (ntfs_sds_to_str(a_fs_file->fs_info, sds, sid_str)) {
        tsk_release_lock(&ntfs->sid_lock);
        tsk_error_set_errstr2("- ntfs_file_get_sidstr:SI attribute");
        return 1;
    }
    tsk_release_lock(&ntfs->sid_lock);
    return 0;
#else
    *sid_str = NULL;
    tsk_error_reset();
    tsk_error_set_errno(TSK_ERR_FS_UNSUPFUNC);
    tsk_error_set_errstr("Unsupported function");
    return 1;
#endif
}


#if TSK_USE_SID
/** \internal
 * Process all the $SII entries into a single array by removing all the Attribute Headers.
 * Note: This routine assumes &ntfs->sid_lock is locked by the caller.
 * @param fs File system structure to store results into
 * @param sii_buffer Buffer of raw $SII entries to parse
 */
static void
ntfs_proc_sii(TSK_FS_INFO * fs, NTFS_SXX_BUFFER * sii_buffer)
{
    unsigned int sii_buffer_offset = 0;
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;
    ntfs_attr_sii *sii;

    if ((fs == NULL) || (sii_buffer == NULL)
        || (ntfs->sii_data.buffer == NULL))
        return;

    /* Loop by cluster size */
    for (sii_buffer_offset = 0; sii_buffer_offset < sii_buffer->size;
        sii_buffer_offset += ntfs->idx_rsize_b) {

        uint8_t* idx_buffer_end = 0;

        ntfs_idxrec *idxrec =
            (ntfs_idxrec *) & sii_buffer->buffer[sii_buffer_offset];

        // stop processing if we hit corrupt data
        if (tsk_getu32(fs->endian, idxrec->list.begin_off) > ntfs->idx_rsize_b) {
            if (tsk_verbose)
                tsk_fprintf(stderr, "ntfs_proc_sii: corrupt offset\n");
            break;
        }
        else if (tsk_getu32(fs->endian, idxrec->list.bufend_off) > ntfs->idx_rsize_b) {
            if (tsk_verbose)
                tsk_fprintf(stderr, "ntfs_proc_sii: corrupt offset\n");
            break;
        }
        else if (tsk_getu32(fs->endian, idxrec->list.begin_off) > tsk_getu32(fs->endian, idxrec->list.bufend_off)) {
            if (tsk_verbose)
                tsk_fprintf(stderr, "ntfs_proc_sii: corrupt offset\n");
            break;
        }

        // get pointer to first record
    uint8_t* sii_data_ptr = ((uint8_t*)& idxrec->list +
      tsk_getu32(fs->endian, idxrec->list.begin_off));

        // where last record ends
        idx_buffer_end = (uint8_t*) & idxrec->list +
            tsk_getu32(fs->endian, idxrec->list.bufend_off);


        // copy records into NTFS_INFO
    while (sii_data_ptr + sizeof(ntfs_attr_sii) <= idx_buffer_end) {
      /* make sure we don't go over bounds of ntfs->sii_data.buffer */
      if ((ntfs->sii_data.used + 1) * sizeof(ntfs_attr_sii) > ntfs->sii_data.size) {
        if (tsk_verbose)
          tsk_fprintf(stderr, "ntfs_proc_sii: data buffer too small\n");
        return; // reached end of ntfs->sii_data.buffer
      }

      // It appears that perhaps older versions of NTFS always had entries of length 0x28. Now it appears we also can
      // have entries of length 0x30. And there are also some entries that take up 0x28 bytes but have their length set to 0x10.

      // 1400140000000000280004000000000002110000f233505302110000a026320000000000ec000000  // Normal entry of length 0x28
      // 0000000000000000100000000200000003110000a65c02000311000090273200000000005c010000  // Possibly deleted? entry of length 0x28 but reporting length 0x10
      // 140014000000000030000400010000001d150000abb032671d150000805a3a0000000000e80000006800000000000000  // Entry of length 0x30. Unclear what the eight final bytes are
      // 00000000000000001800000003001b00540000000000000067110000a0823200000000003c0100005400000000000000  // I think this is the possibly deleted form of a long entry
      //
      // I haven't been able to find any documentation of what's going on - it's all old and says the entry length will be 0x28. The flags
      // are also different across these three types but I also can't find any documentation on what they mean. So this is a best guess on
      // how we should handle things:
      // - If the length field is 0x30 or the first two fields are null and the length is 0x18, save the entry and advance 0x30 bytes.
      //         The last eight bytes on the long entries will be ignored.
      // - Otherwise save the entry and advance by 0x28 bytes.
      //
      sii = (ntfs_attr_sii*)sii_data_ptr;
      int data_off = tsk_getu16(fs->endian, sii->data_off);
      int data_size = tsk_getu16(fs->endian, sii->size);
      int ent_size = tsk_getu16(fs->endian, sii->ent_size);

      // Copy the entry. It seems like we could have a check here that the first two fields are 0x14
      // but we don't know for sure that not having those indicates an invalid entry.
      memcpy(ntfs->sii_data.buffer +
        (ntfs->sii_data.used * sizeof(ntfs_attr_sii)), sii_data_ptr,
        sizeof(ntfs_attr_sii));
      ntfs->sii_data.used++;

      // Advance the pointer
      if (ent_size == 0x30 || (data_off == 0 && data_size == 0 && ent_size == 0x18)) {
        sii_data_ptr += 0x30;
      }
      else {
        sii_data_ptr += 0x28;
      }

/*
        printf("Security id %d is at offset 0x%I64x for 0x%x bytes\n", tsk_getu32(fs->endian,sii->key_sec_id),
                                       tsk_getu64(fs->endian,sii->sec_desc_off),
                                       tsk_getu32(fs->endian,sii->sec_desc_size));
      }
      else
      {
        printf("\n\tOffset to data %x Size of data %x Size of Index entry %x\n", tsk_getu16(fs->endian,sii->data_off),
                                           tsk_getu16(fs->endian,sii->size),
                                           tsk_getu16(fs->endian,sii->ent_size));
        printf("\tSecurity id %d is at offset 0x%I64x for 0x%x bytes\n\n", tsk_getu32(fs->endian,sii->key_sec_id),
                                       tsk_getu64(fs->endian,sii->sec_desc_off),
                                       tsk_getu32(fs->endian,sii->sec_desc_size));
      }
*/
        }
    }
}


/*
 * Load the $Secure attributes so that we can identify the user.
 *
 * Note: This routine is called only from ntfs_open and therefore does
 * not need to lock ntfs->sid_lock.
 *
 * @returns 1 on error (which occurs only if malloc or other system error).
 */
static uint8_t
ntfs_load_secure(NTFS_INFO * ntfs)
{
    TSK_FS_INFO *fs = (TSK_FS_INFO *) & ntfs->fs_info;
    TSK_FS_META *fs_meta = NULL;
    const TSK_FS_ATTR *fs_attr_sds = NULL;
    const TSK_FS_ATTR *fs_attr_sii = NULL;
    NTFS_SXX_BUFFER sii_buffer;
    ssize_t cnt;

    ntfs->sii_data.buffer = NULL;
    ntfs->sii_data.size = 0;
    ntfs->sii_data.used = 0;
    ntfs->sds_data.buffer = NULL;
    ntfs->sds_data.size = 0;
    ntfs->sds_data.used = 0;


    // Open $Secure. The $SDS stream contains all the security descriptors
    // and is indexed by $SII and $SDH.
    std::unique_ptr<TSK_FS_FILE, decltype(&tsk_fs_file_close)> secure{
        tsk_fs_file_open_meta(fs, NULL, NTFS_MFT_SECURE),
        tsk_fs_file_close
    };

    if (!secure) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_load_secure: error opening $Secure file: %s\n",
                tsk_error_get_errstr());
        tsk_error_reset();
        return 0;
    }

    // Make sure the TSK_FS_META is not NULL. We need it to get the
    // $SII and $SDH attributes.
    fs_meta = secure->meta;
    if (!fs_meta) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_load_secure: $Secure file has no attributes\n");
        tsk_error_reset();
        return 0;
    }

    // Get the $SII attribute.
    fs_attr_sii =
        tsk_fs_attrlist_get_name_type(fs_meta->attr, (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_IDXALLOC,
        "$SII\0");
    if (!fs_attr_sii) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_load_secure: error getting $Secure:$SII IDX_ALLOC attribute\n");
        tsk_error_reset();
        return 0;

    }

    // Get the $SDS attribute.
    fs_attr_sds = tsk_fs_attrlist_get(fs_meta->attr, (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_DATA);
    if (!fs_attr_sds) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_load_secure: error getting $Secure:$SDS $Data attribute\n");
        tsk_error_reset();
        return 0;
    }

    /* First we read in $SII to a local buffer adn then process it into NTFS_INFO */

    // Allocate local space for the entire $SII stream.
    sii_buffer.size = (size_t) roundup(fs_attr_sii->size, fs->block_size);
    sii_buffer.used = 0;

    // arbitrary check because we had problems before with alloc too much memory
    if (sii_buffer.size > 64000000) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_load_secure: sii_buffer.size is too large: %z\n",
                sii_buffer.size);
        return 0;
    }
    if ((sii_buffer.buffer = (char*) tsk_malloc(sii_buffer.size)) == NULL) {
        return 1;
    }

    // Read in the raw $SII stream.
    cnt =
        tsk_fs_attr_read(fs_attr_sii, 0, sii_buffer.buffer,
        sii_buffer.size, TSK_FS_FILE_READ_FLAG_NONE);
    if (cnt != (ssize_t)sii_buffer.size) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_load_secure: error reading $Secure:$SII attribute: %s\n",
                tsk_error_get_errstr());
        tsk_error_reset();

        free(sii_buffer.buffer);
        return 0;
    }

    // allocate the structure for the processed version of the data
    ntfs->sii_data.used = 0;    // use this to count the number of $SII entries
    if ((ntfs->sii_data.buffer =
            (char *) tsk_malloc(sii_buffer.size)) == NULL) {
        free(sii_buffer.buffer);
        return 1;
    }
    ntfs->sii_data.size = sii_buffer.size;

    // parse sii_buffer into ntfs->sii_data.
    ntfs_proc_sii(fs, &sii_buffer);
    free(sii_buffer.buffer);

    /* Now we copy $SDS into NTFS_INFO. We do not do any processing in this step. */

    // Allocate space for the entire $SDS stream with all the security
    // descriptors. We should be able to use the $SII offset to index
    // into the $SDS stream.
    ntfs->sds_data.size = (size_t) fs_attr_sds->size;
    // arbitrary check because we had problems before with alloc too much memory
    if (ntfs->sds_data.size > 64000000) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_load_secure: ntfs->sds_data.size is too large: %z\n",
                ntfs->sds_data.size);
        free(ntfs->sii_data.buffer);
        ntfs->sii_data.buffer = NULL;
        ntfs->sii_data.used = 0;
        ntfs->sii_data.size = 0;
        return 0;
    }
    ntfs->sds_data.used = 0;
    if ((ntfs->sds_data.buffer =
            (char *) tsk_malloc(ntfs->sds_data.size)) == NULL) {
        free(ntfs->sii_data.buffer);
        ntfs->sii_data.buffer = NULL;
        ntfs->sii_data.used = 0;
        ntfs->sii_data.size = 0;
        return 1;
    }

    // Read in the raw $SDS ($DATA) stream.
    cnt =
        tsk_fs_attr_read(fs_attr_sds, 0,
        ntfs->sds_data.buffer, ntfs->sds_data.size,
        TSK_FS_FILE_READ_FLAG_NONE);
    if (cnt != (ssize_t)ntfs->sds_data.size) {
        if (tsk_verbose)
            tsk_fprintf(stderr,
                "ntfs_load_secure: error reading $Secure:$SDS attribute: %s\n",
                tsk_error_get_errstr());
        tsk_error_reset();

        free(ntfs->sii_data.buffer);
        ntfs->sii_data.buffer = NULL;
        ntfs->sii_data.used = 0;
        ntfs->sii_data.size = 0;
        free(ntfs->sds_data.buffer);
        ntfs->sds_data.buffer = NULL;
        ntfs->sds_data.used = 0;
        ntfs->sds_data.size = 0;
        return 0;
    }

    return 0;
}

#endif

/**********************************************************************
 *
 *  Exported Walk Functions
 *
 **********************************************************************/


static TSK_FS_BLOCK_FLAG_ENUM
ntfs_block_getflags(TSK_FS_INFO * a_fs, TSK_DADDR_T a_addr)
{
    NTFS_INFO *ntfs = (NTFS_INFO *) a_fs;
    int retval;
    int flags = 0;

    /* identify if the cluster is allocated or not */
    retval = is_clustalloc(ntfs, a_addr);
    if (retval == 1)
        flags = TSK_FS_BLOCK_FLAG_ALLOC;
    else if (retval == 0)
        flags = TSK_FS_BLOCK_FLAG_UNALLOC;

    return (TSK_FS_BLOCK_FLAG_ENUM) flags;
}



/*
 * flags: TSK_FS_BLOCK_FLAG_ALLOC and FS_FLAG_UNALLOC
 *
 * @@@ We should probably consider some data META, but it is tough with
 * the NTFS design ...
 */
static uint8_t
ntfs_block_walk(TSK_FS_INFO * fs,
    TSK_DADDR_T a_start_blk, TSK_DADDR_T a_end_blk,
    TSK_FS_BLOCK_WALK_FLAG_ENUM a_flags, TSK_FS_BLOCK_WALK_CB a_action,
    void *a_ptr)
{
    const char *myname = "ntfs_block_walk";
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;
    TSK_DADDR_T addr;
    TSK_FS_BLOCK *fs_block;

    // clean up any error messages that are lying around
    tsk_error_reset();

    /*
     * Sanity checks.
     */
    if (a_start_blk < fs->first_block || a_start_blk > fs->last_block) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_WALK_RNG);
        tsk_error_set_errstr("%s: start block: %" PRIuDADDR "", myname,
            a_start_blk);
        return 1;
    }
    else if (a_end_blk < fs->first_block || a_end_blk > fs->last_block) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_WALK_RNG);
        tsk_error_set_errstr("%s: last block: %" PRIuDADDR "", myname,
            a_end_blk);
        return 1;
    }

    /* Sanity check on a_flags -- make sure at least one ALLOC is set */
    if (((a_flags & TSK_FS_BLOCK_WALK_FLAG_ALLOC) == 0) &&
        ((a_flags & TSK_FS_BLOCK_WALK_FLAG_UNALLOC) == 0)) {
        a_flags = (TSK_FS_BLOCK_WALK_FLAG_ENUM)
            (a_flags | TSK_FS_BLOCK_WALK_FLAG_ALLOC |
            TSK_FS_BLOCK_WALK_FLAG_UNALLOC);
    }
    if (((a_flags & TSK_FS_BLOCK_WALK_FLAG_META) == 0) &&
        ((a_flags & TSK_FS_BLOCK_WALK_FLAG_CONT) == 0)) {
        a_flags = (TSK_FS_BLOCK_WALK_FLAG_ENUM)
            (a_flags | TSK_FS_BLOCK_WALK_FLAG_CONT | TSK_FS_BLOCK_WALK_FLAG_META);
    }


    if ((fs_block = tsk_fs_block_alloc(fs)) == NULL) {
        return 1;
    }

    /* Cycle through the blocks */
    for (addr = a_start_blk; addr <= a_end_blk; addr++) {
        int retval;
        int myflags;

        /* identify if the cluster is allocated or not */
        retval = is_clustalloc(ntfs, addr);
        if (retval == -1) {
            tsk_fs_block_free(fs_block);
            return 1;
        }

        else if (retval == 1) {
            myflags = TSK_FS_BLOCK_FLAG_ALLOC;
        }
        else {
            myflags = TSK_FS_BLOCK_FLAG_UNALLOC;
        }

        // test if we should call the callback with this one
        if ((myflags & TSK_FS_BLOCK_FLAG_ALLOC)
            && (!(a_flags & TSK_FS_BLOCK_WALK_FLAG_ALLOC)))
            continue;
        else if ((myflags & TSK_FS_BLOCK_FLAG_UNALLOC)
            && (!(a_flags & TSK_FS_BLOCK_WALK_FLAG_UNALLOC)))
            continue;

        if (a_flags & TSK_FS_BLOCK_WALK_FLAG_AONLY)
            myflags |= TSK_FS_BLOCK_FLAG_AONLY;

        if (tsk_fs_block_get_flag(fs, fs_block, addr,
                (TSK_FS_BLOCK_FLAG_ENUM) myflags) == NULL) {
            tsk_error_set_errstr2
                ("ntfs_block_walk: Error reading block at %" PRIuDADDR,
                addr);
            tsk_fs_block_free(fs_block);
            return 1;
        }

        retval = a_action(fs_block, a_ptr);
        if (retval == TSK_WALK_STOP) {
            break;
        }
        else if (retval == TSK_WALK_ERROR) {
            tsk_fs_block_free(fs_block);
            return 1;
        }
    }

    tsk_fs_block_free(fs_block);
    return 0;
}



/*
 * inode_walk
 *
 * Flags: TSK_FS_META_FLAG_ALLOC, TSK_FS_META_FLAG_UNALLOC,
 * TSK_FS_META_FLAG_USED, TSK_FS_META_FLAG_UNUSED, TSK_FS_META_FLAG_ORPHAN
 *
 * Note that with ORPHAN, entries will be found that can also be
 * found by searching based on parent directories (if parent directory is
 * known)
 */
static uint8_t
ntfs_inode_walk(TSK_FS_INFO * fs, TSK_INUM_T start_inum,
    TSK_INUM_T end_inum, TSK_FS_META_FLAG_ENUM flags,
    TSK_FS_META_WALK_CB a_action, void *ptr)
{
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;
    unsigned int myflags;
    TSK_INUM_T mftnum;
    TSK_INUM_T end_inum_tmp;
    ntfs_mft *mft;
    /*
     * Sanity checks.
     */
    if (start_inum < fs->first_inum) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_WALK_RNG);
        tsk_error_set_errstr
            ("inode_walk: Starting inode number is too small (%" PRIuINUM
            ")", start_inum);
        return 1;
    }
    if (start_inum > fs->last_inum) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_WALK_RNG);
        tsk_error_set_errstr
            ("inode_walk: Starting inode number is too large (%" PRIuINUM
            ")", start_inum);
        return 1;
    }
    if (end_inum < fs->first_inum) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_WALK_RNG);
        tsk_error_set_errstr
            ("inode_walk: Ending inode number is too small (%" PRIuINUM
            ")", end_inum);
        return 1;
    }
    if (end_inum > fs->last_inum) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_WALK_RNG);
        tsk_error_set_errstr("Ending inode number is too large (%" PRIuINUM
            ")", end_inum);
        return 1;
    }


    /* If ORPHAN is wanted, then make sure that the flags are correct */
    if (flags & TSK_FS_META_FLAG_ORPHAN) {
        flags = (TSK_FS_META_FLAG_ENUM) (flags | TSK_FS_META_FLAG_UNALLOC);
        flags = (TSK_FS_META_FLAG_ENUM) (flags & ~TSK_FS_META_FLAG_ALLOC);
        flags = (TSK_FS_META_FLAG_ENUM) (flags | TSK_FS_META_FLAG_USED);
        flags = (TSK_FS_META_FLAG_ENUM) (flags & ~TSK_FS_META_FLAG_UNUSED);
    }

    else {
        if (((flags & TSK_FS_META_FLAG_ALLOC) == 0) &&
            ((flags & TSK_FS_META_FLAG_UNALLOC) == 0)) {
            flags = (TSK_FS_META_FLAG_ENUM) (flags | TSK_FS_META_FLAG_ALLOC | TSK_FS_META_FLAG_UNALLOC);
        }

        /* If neither of the USED or UNUSED flags are set, then set them
         * both
         */
        if (((flags & TSK_FS_META_FLAG_USED) == 0) &&
            ((flags & TSK_FS_META_FLAG_UNUSED) == 0)) {
            flags = (TSK_FS_META_FLAG_ENUM) (flags | TSK_FS_META_FLAG_USED | TSK_FS_META_FLAG_UNUSED);
        }
    }


    /* If we are looking for orphan files and have not yet filled
     * in the list of unalloc inodes that are pointed to, then fill
     * in the list
     * */
    if ((flags & TSK_FS_META_FLAG_ORPHAN)) {
        if (tsk_fs_dir_load_inum_named(fs) != TSK_OK) {
            tsk_error_errstr2_concat
                ("- ntfs_inode_walk: identifying inodes allocated by file names");
            return 1;
        }
    }

    std::unique_ptr<TSK_FS_FILE, decltype(&tsk_fs_file_close)> fs_file{
        tsk_fs_file_alloc(fs),
        tsk_fs_file_close
    };

    if (!fs_file)
        return 1;

    if ((fs_file->meta = tsk_fs_meta_alloc(NTFS_FILE_CONTENT_LEN)) == NULL) {
        // JRB: Coverity CID: 348
        return 1;
    }

    if ((mft = (ntfs_mft *) tsk_malloc(ntfs->mft_rsize_b)) == NULL) {
        return 1;
    }
    // we need to handle fs->last_inum specially because it is for the
    // virtual ORPHANS directory.  Handle it outside of the loop.
    if (end_inum == TSK_FS_ORPHANDIR_INUM(fs))
        end_inum_tmp = end_inum - 1;
    else
        end_inum_tmp = end_inum;


    for (mftnum = start_inum; mftnum <= end_inum_tmp; mftnum++) {
        int retval;
        TSK_RETVAL_ENUM retval2;

        /* read MFT entry in to NTFS_INFO */
        if ((retval2 =
                ntfs_dinode_lookup(ntfs, (char *) mft,
                    mftnum, & (fs_file->meta->start_of_inode))) != TSK_OK) {
            // if the entry is corrupt, then skip to the next one
            if (retval2 == TSK_COR) {
                if (tsk_verbose)
                    tsk_error_print(stderr);
                tsk_error_reset();
                continue;
            }
            free(mft);
            return 1;
        }

        /* we only want to look at base file records
         * (extended are because the base could not fit into one)
         */
        if (tsk_getu48(fs->endian, mft->base_ref) != NTFS_MFT_BASE)
            continue;

        /* NOTE: We could add a sanity check here with the MFT bitmap
         * to validate of the INUSE flag and bitmap are in agreement
         */
        /* check flags */
        myflags =
            ((tsk_getu16(fs->endian, mft->flags) &
                NTFS_MFT_INUSE) ? TSK_FS_META_FLAG_ALLOC :
            TSK_FS_META_FLAG_UNALLOC);

        /* If we want only orphans, then check if this
         * inode is in the seen list
         * */
        if ((myflags & TSK_FS_META_FLAG_UNALLOC) &&
            (flags & TSK_FS_META_FLAG_ORPHAN) &&
            (tsk_fs_dir_find_inum_named(fs, mftnum))) {
            continue;
        }

        /* copy into generic format */
        if ((retval =
                ntfs_dinode_copy(ntfs, fs_file.get(), (char *) mft,
                    mftnum)) != TSK_OK) {
            // continue on if there were only corruption problems
            if (retval == TSK_COR) {
                if (tsk_verbose)
                    tsk_error_print(stderr);
                tsk_error_reset();
                continue;
            }
            free(mft);
            return 1;
        }

        myflags |=
            (fs_file->meta->flags & (TSK_FS_META_FLAG_USED |
                TSK_FS_META_FLAG_UNUSED));
        if ((flags & myflags) != myflags)
            continue;

        /* call action */
        retval = a_action(fs_file.get(), ptr);
        if (retval == TSK_WALK_STOP) {
            free(mft);
            return 0;
        }
        else if (retval == TSK_WALK_ERROR) {
            free(mft);
            return 1;
        }
    }

    // handle the virtual orphans folder if they asked for it
    if ((end_inum == TSK_FS_ORPHANDIR_INUM(fs))
        && (flags & TSK_FS_META_FLAG_ALLOC)
        && (flags & TSK_FS_META_FLAG_USED)) {
        int retval;

        if (tsk_fs_dir_make_orphan_dir_meta(fs, fs_file->meta)) {
            free(mft);
            return 1;
        }
        /* call action */
        retval = a_action(fs_file.get(), ptr);
        if (retval == TSK_WALK_STOP) {
            free(mft);
            return 0;
        }
        else if (retval == TSK_WALK_ERROR) {
            free(mft);
            return 1;
        }
    }

    free(mft);
    return 0;
}



static uint8_t
ntfs_fscheck(
  [[maybe_unused]] TSK_FS_INFO * fs,
  [[maybe_unused]] FILE * hFile)
{
    tsk_error_reset();
    tsk_error_set_errno(TSK_ERR_FS_UNSUPFUNC);
    tsk_error_set_errstr("fscheck not implemented for NTFS yet");
    return 1;
}


/**
 * Print details about the file system to a file handle.
 *
 * @param fs File system to print details on
 * @param hFile File handle to print text to
 *
 * @returns 1 on error and 0 on success
 */
static uint8_t
ntfs_fsstat(TSK_FS_INFO * fs, FILE * hFile)
{
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;
    const TSK_FS_ATTR *fs_attr;
    char asc[512];
    ntfs_attrdef *attrdeftmp;

    tsk_fprintf(hFile, "FILE SYSTEM INFORMATION\n");
    tsk_fprintf(hFile, "--------------------------------------------\n");
    tsk_fprintf(hFile, "File System Type: NTFS\n");
    tsk_fprintf(hFile,
        "Volume Serial Number: %.16" PRIX64
        "\n", tsk_getu64(fs->endian, ntfs->fs->serial));
    tsk_fprintf(hFile, "OEM Name: %c%c%c%c%c%c%c%c\n",
        ntfs->fs->oemname[0],
        ntfs->fs->oemname[1],
        ntfs->fs->oemname[2],
        ntfs->fs->oemname[3],
        ntfs->fs->oemname[4],
        ntfs->fs->oemname[5], ntfs->fs->oemname[6], ntfs->fs->oemname[7]);
    /*
     * Volume
     */
    std::unique_ptr<TSK_FS_FILE, decltype(&tsk_fs_file_close)> fs_file{
        tsk_fs_file_open_meta(fs, NULL, NTFS_MFT_VOL),
        tsk_fs_file_close
    };

    if (!fs_file) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_NUM);
        tsk_error_errstr2_concat
            (" - fsstat: Error finding Volume MFT Entry");
        return 1;
    }

    fs_attr = tsk_fs_attrlist_get(fs_file->meta->attr, (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_VNAME);
    if (!fs_attr) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_INODE_COR);
        tsk_error_set_errstr("Volume Name attribute not found in $Volume");
        return 1;
    }

    if ((fs_attr->flags & TSK_FS_ATTR_RES)
        && (fs_attr->size)) {

        UTF16 *name16 = (UTF16 *) fs_attr->rd.buf;
        UTF8 *name8 = (UTF8 *) asc;
        int retVal;
        retVal =
            tsk_UTF16toUTF8(fs->endian, (const UTF16 **) &name16,
            (UTF16 *) ((uintptr_t) name16 +
                (int) fs_attr->size), &name8,
            (UTF8 *) ((uintptr_t) name8 + sizeof(asc)),
            TSKlenientConversion);
        if (retVal != TSKconversionOK) {
            if (tsk_verbose)
                tsk_fprintf(stderr,
                    "fsstat: Error converting NTFS Volume label to UTF8: %d",
                    retVal);
            *name8 = '\0';
        }

        /* Make sure it is NULL Terminated */
        else if ((uintptr_t) name8 >= (uintptr_t) asc + sizeof(asc))
            asc[sizeof(asc) - 1] = '\0';
        else
            *name8 = '\0';
        tsk_fprintf(hFile, "Volume Name: %s\n", asc);
    }

    fs_attr = NULL;
    if (ntfs->ver == NTFS_VINFO_NT)
        tsk_fprintf(hFile, "Version: Windows NT\n");
    else if (ntfs->ver == NTFS_VINFO_2K)
        tsk_fprintf(hFile, "Version: Windows 2000\n");
    else if (ntfs->ver == NTFS_VINFO_XP)
        tsk_fprintf(hFile, "Version: Windows XP\n");
    tsk_fprintf(hFile, "\nMETADATA INFORMATION\n");
    tsk_fprintf(hFile, "--------------------------------------------\n");
    tsk_fprintf(hFile,
        "First Cluster of MFT: %" PRIu64 "\n",
        tsk_getu64(fs->endian, ntfs->fs->mft_clust));
    tsk_fprintf(hFile,
        "First Cluster of MFT Mirror: %"
        PRIu64 "\n", tsk_getu64(fs->endian, ntfs->fs->mftm_clust));
    tsk_fprintf(hFile,
        "Size of MFT Entries: %" PRIu16 " bytes\n", ntfs->mft_rsize_b);
    tsk_fprintf(hFile,
        "Size of Index Records: %" PRIu16 " bytes\n", ntfs->idx_rsize_b);
    tsk_fprintf(hFile,
        "Range: %" PRIuINUM " - %" PRIuINUM
        "\n", fs->first_inum, fs->last_inum);
    tsk_fprintf(hFile, "Root Directory: %" PRIuINUM "\n", fs->root_inum);
    tsk_fprintf(hFile, "\nCONTENT INFORMATION\n");
    tsk_fprintf(hFile, "--------------------------------------------\n");
    tsk_fprintf(hFile, "Sector Size: %" PRIu16 "\n", ntfs->ssize_b);
    tsk_fprintf(hFile, "Cluster Size: %" PRIu16 "\n", ntfs->csize_b);
    tsk_fprintf(hFile,
        "Total Cluster Range: %" PRIuDADDR
        " - %" PRIuDADDR "\n", fs->first_block, fs->last_block);

    if (fs->last_block != fs->last_block_act)
        tsk_fprintf(hFile,
            "Total Range in Image: %" PRIuDADDR " - %" PRIuDADDR "\n",
            fs->first_block, fs->last_block_act);

    tsk_fprintf(hFile,
        "Total Sector Range: 0 - %" PRIu64
        "\n", tsk_getu64(fs->endian, ntfs->fs->vol_size_s) - 1);
    /*
     * Attrdef Info
     */
    tsk_fprintf(hFile, "\n$AttrDef Attribute Values:\n");
    if (!ntfs->attrdef) {
        if (ntfs_load_attrdef(ntfs)) {
            tsk_fprintf(hFile, "Error loading attribute definitions\n");
            goto attrdef_egress;
        }
    }

    attrdeftmp = ntfs->attrdef;
    while ((((uintptr_t) attrdeftmp - (uintptr_t) ntfs->attrdef +
                sizeof(ntfs_attrdef)) < ntfs->attrdef_len) &&
        (tsk_getu32(fs->endian, attrdeftmp->type))) {
        UTF16 *name16 = (UTF16 *) attrdeftmp->label;
        UTF8 *name8 = (UTF8 *) asc;
        int retVal;
        retVal =
            tsk_UTF16toUTF8(fs->endian, (const UTF16 **) &name16,
            (UTF16 *) ((uintptr_t) name16 +
                sizeof(attrdeftmp->label)),
            &name8,
            (UTF8 *) ((uintptr_t) name8 + sizeof(asc)),
            TSKlenientConversion);
        if (retVal != TSKconversionOK) {
            if (tsk_verbose)
                tsk_fprintf(stderr,
                    "fsstat: Error converting NTFS attribute def label to UTF8: %d",
                    retVal);
            *name8 = '\0';
        }

        /* Make sure it is NULL Terminated */
        else if ((uintptr_t) name8 >= (uintptr_t) asc + sizeof(asc))
            asc[sizeof(asc) - 1] = '\0';
        else
            *name8 = '\0';
        tsk_fprintf(hFile, "%s (%" PRIu32 ")   ",
            asc, tsk_getu32(fs->endian, attrdeftmp->type));
        if ((tsk_getu64(fs->endian, attrdeftmp->minsize) == 0) &&
            (tsk_getu64(fs->endian,
                    attrdeftmp->maxsize) == 0xffffffffffffffffULL)) {

            tsk_fprintf(hFile, "Size: No Limit");
        }
        else {
            tsk_fprintf(hFile, "Size: %" PRIu64 "-%" PRIu64,
                tsk_getu64(fs->endian, attrdeftmp->minsize),
                tsk_getu64(fs->endian, attrdeftmp->maxsize));
        }

        tsk_fprintf(hFile, "   Flags: %s%s%s\n",
            (tsk_getu32(fs->endian, attrdeftmp->flags) &
                NTFS_ATTRDEF_FLAGS_RES ? "Resident" :
                ""), (tsk_getu32(fs->endian,
                    attrdeftmp->flags) &
                NTFS_ATTRDEF_FLAGS_NONRES ?
                "Non-resident" : ""),
            (tsk_getu32(fs->endian, attrdeftmp->flags) &
                NTFS_ATTRDEF_FLAGS_IDX ? ",Index" : ""));
        attrdeftmp++;
    }

  attrdef_egress:

    return 0;
}


/************************* istat *******************************/

#define NTFS_PRINT_WIDTH   8
typedef struct {
    FILE *hFile;
    int idx;
} NTFS_PRINT_ADDR;
static TSK_WALK_RET_ENUM
print_addr_act(
  [[maybe_unused]] TSK_FS_FILE * fs_file,
  [[maybe_unused]] TSK_OFF_T a_off,
  TSK_DADDR_T addr,
  [[maybe_unused]] char *buf,
  [[maybe_unused]] size_t size,
  [[maybe_unused]] TSK_FS_BLOCK_FLAG_ENUM flags,
  void *ptr)
{
    NTFS_PRINT_ADDR *print = (NTFS_PRINT_ADDR *) ptr;
    tsk_fprintf(print->hFile, "%" PRIuDADDR " ", addr);
    if (++(print->idx) == NTFS_PRINT_WIDTH) {
        tsk_fprintf(print->hFile, "\n");
        print->idx = 0;
    }

    return TSK_WALK_CONT;
}

/**
 * Print details on a specific file to a file handle.
 *
 * @param fs File system file is located in
 * @param hFile File name to print text to
 * @param inum Address of file in file system
 * @param numblock The number of blocks in file to force print (can go beyond file size)
 * @param sec_skew Clock skew in seconds to also print times in
 *
 * @returns 1 on error and 0 on success
 */
static uint8_t
ntfs_istat(
  TSK_FS_INFO * fs,
  TSK_FS_ISTAT_FLAG_ENUM istat_flags,
  FILE * hFile,
  TSK_INUM_T inum,
  [[maybe_unused]] TSK_DADDR_T numblock,
  int32_t sec_skew)
{
    const TSK_FS_ATTR *fs_attr;
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;
    ntfs_mft *mft;
    char timeBuf[128];
    int idx;

    // clean up any error messages that are lying around
    tsk_error_reset();

    if ((mft = (ntfs_mft *) tsk_malloc(ntfs->mft_rsize_b)) == NULL) {
        return 1;
    }

    if (ntfs_dinode_lookup(ntfs, (char *) mft, inum, 0)) {
        free(mft);
        return 1;
    }

    std::unique_ptr<TSK_FS_FILE, decltype(&tsk_fs_file_close)> fs_file{
        tsk_fs_file_open_meta(fs, NULL, inum),
        tsk_fs_file_close
    };

    if (!fs_file) {
        tsk_error_errstr2_concat(" - istat");
        free(mft);
        return 1;
    }

    tsk_fprintf(hFile, "MFT Entry Header Values:\n");
    tsk_fprintf(hFile,
        "Entry: %" PRIuINUM
        "        Sequence: %" PRIu32 "\n", inum, fs_file->meta->seq);
    if (tsk_getu48(fs->endian, mft->base_ref) != 0) {
        tsk_fprintf(hFile,
            "Base File Record: %" PRIu64 "\n",
            (uint64_t) tsk_getu48(fs->endian, mft->base_ref));
    }

    tsk_fprintf(hFile,
        "$LogFile Sequence Number: %" PRIu64
        "\n", tsk_getu64(fs->endian, mft->lsn));
    tsk_fprintf(hFile, "%sAllocated %s\n",
        (fs_file->meta->flags & TSK_FS_META_FLAG_ALLOC) ? "" :
        "Not ",
        TSK_FS_IS_DIR_META(fs_file->meta->type) ? "Directory" : "File");
    tsk_fprintf(hFile, "Links: %u\n", fs_file->meta->nlink);

    /* STANDARD_INFORMATION info */
    fs_attr = tsk_fs_attrlist_get(fs_file->meta->attr, (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_SI);
    if (fs_attr) {
        ntfs_attr_si *si = (ntfs_attr_si *) fs_attr->rd.buf;
        char *sid_str;

        int a = 0;
        tsk_fprintf(hFile, "\n$STANDARD_INFORMATION Attribute Values:\n");
        tsk_fprintf(hFile, "Flags: ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_RO)
            tsk_fprintf(hFile, "%sRead Only", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_HID)
            tsk_fprintf(hFile, "%sHidden", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_SYS)
            tsk_fprintf(hFile, "%sSystem", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_ARCH)
            tsk_fprintf(hFile, "%sArchive", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_DEV)
            tsk_fprintf(hFile, "%sDevice", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_NORM)
            tsk_fprintf(hFile, "%sNormal", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_TEMP)
            tsk_fprintf(hFile, "%sTemporary", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_SPAR)
            tsk_fprintf(hFile, "%sSparse", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_REP)
            tsk_fprintf(hFile, "%sReparse Point", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_COMP)
            tsk_fprintf(hFile, "%sCompressed", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_OFF)
            tsk_fprintf(hFile, "%sOffline", a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_NOIDX)
            tsk_fprintf(hFile, "%sNot Content Indexed",
                a++ == 0 ? "" : ", ");
        if (tsk_getu32(fs->endian, si->dos) & NTFS_SI_ENC)
            tsk_fprintf(hFile, "%sEncrypted", a++ == 0 ? "" : ", ");
        tsk_fprintf(hFile, "\n");
        tsk_fprintf(hFile, "Owner ID: %" PRIu32 "\n",
            tsk_getu32(fs->endian, si->own_id));

#if TSK_USE_SID
        ntfs_file_get_sidstr(fs_file.get(), &sid_str);

        tsk_fprintf(hFile, "Security ID: %" PRIu32 "  (%s)\n",
            tsk_getu32(fs->endian, si->sec_id), sid_str ? sid_str : "");
        free(sid_str);
        sid_str = NULL;
#endif


        if (tsk_getu32(fs->endian, si->maxver) != 0) {
            tsk_fprintf(hFile,
                "Version %" PRIu32 " of %" PRIu32
                "\n", tsk_getu32(fs->endian, si->ver),
                tsk_getu32(fs->endian, si->maxver));
        }

        if (tsk_getu64(fs->endian, si->quota) != 0) {
            tsk_fprintf(hFile, "Quota Charged: %" PRIu64 "\n",
                tsk_getu64(fs->endian, si->quota));
        }

        if (tsk_getu64(fs->endian, si->usn) != 0) {
            tsk_fprintf(hFile,
                "Last User Journal Update Sequence Number: %"
                PRIu64 "\n", tsk_getu64(fs->endian, si->usn));
        }


        /* Times - take it from fs_file->meta instead of redoing the work */

        if (sec_skew != 0) {
            tsk_fprintf(hFile, "\nAdjusted times:\n");
            if (fs_file->meta->mtime)
                fs_file->meta->mtime -= sec_skew;
            if (fs_file->meta->atime)
                fs_file->meta->atime -= sec_skew;
            if (fs_file->meta->ctime)
                fs_file->meta->ctime -= sec_skew;
            if (fs_file->meta->crtime)
                fs_file->meta->crtime -= sec_skew;

            tsk_fprintf(hFile, "Created:\t%s\n",
                tsk_fs_time_to_str_subsecs(WITHNANO(fs_file->meta->crtime), timeBuf));
            tsk_fprintf(hFile, "File Modified:\t%s\n",
                tsk_fs_time_to_str_subsecs(WITHNANO(fs_file->meta->mtime), timeBuf));
            tsk_fprintf(hFile, "MFT Modified:\t%s\n",
                tsk_fs_time_to_str_subsecs(WITHNANO(fs_file->meta->ctime), timeBuf));
            tsk_fprintf(hFile, "Accessed:\t%s\n",
                tsk_fs_time_to_str_subsecs(WITHNANO(fs_file->meta->atime), timeBuf));

            if (fs_file->meta->mtime)
                fs_file->meta->mtime += sec_skew;
            if (fs_file->meta->atime)
                fs_file->meta->atime += sec_skew;
            if (fs_file->meta->ctime)
                fs_file->meta->ctime += sec_skew;
            if (fs_file->meta->crtime)
                fs_file->meta->crtime += sec_skew;

            tsk_fprintf(hFile, "\nOriginal times:\n");
        }

        tsk_fprintf(hFile, "Created:\t%s\n",
            tsk_fs_time_to_str_subsecs(WITHNANO(fs_file->meta->crtime), timeBuf));
        tsk_fprintf(hFile, "File Modified:\t%s\n",
            tsk_fs_time_to_str_subsecs(WITHNANO(fs_file->meta->mtime), timeBuf));
        tsk_fprintf(hFile, "MFT Modified:\t%s\n",
            tsk_fs_time_to_str_subsecs(WITHNANO(fs_file->meta->ctime), timeBuf));
        tsk_fprintf(hFile, "Accessed:\t%s\n",
            tsk_fs_time_to_str_subsecs(WITHNANO(fs_file->meta->atime), timeBuf));
    }

    /* $FILE_NAME Information */
    for (idx = 0; idx < tsk_fs_attrlist_get_len(fs_file->meta->attr); idx++) {
        ntfs_attr_fname *fname;
        uint64_t flags;
        int a = 0;
        UTF16 *name16;
        UTF8 *name8;
        char name8buf[NTFS_MAXNAMLEN_UTF8 + 1];
        int retVal;

        fs_attr = tsk_fs_attrlist_get_idx(fs_file->meta->attr, idx);
        if (fs_attr->type != NTFS_ATYPE_FNAME) {
            continue;
        }
        fname = (ntfs_attr_fname *) fs_attr->rd.buf;

        tsk_fprintf(hFile, "\n$FILE_NAME Attribute Values:\n");
        flags = tsk_getu64(fs->endian, fname->flags);
        tsk_fprintf(hFile, "Flags: ");
        if (flags & NTFS_FNAME_FLAGS_DIR)
            tsk_fprintf(hFile, "%sDirectory", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_DEV)
            tsk_fprintf(hFile, "%sDevice", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_NORM)
            tsk_fprintf(hFile, "%sNormal", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_RO)
            tsk_fprintf(hFile, "%sRead Only", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_HID)
            tsk_fprintf(hFile, "%sHidden", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_SYS)
            tsk_fprintf(hFile, "%sSystem", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_ARCH)
            tsk_fprintf(hFile, "%sArchive", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_TEMP)
            tsk_fprintf(hFile, "%sTemp", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_SPAR)
            tsk_fprintf(hFile, "%sSparse", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_REP)
            tsk_fprintf(hFile, "%sReparse Point", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_COMP)
            tsk_fprintf(hFile, "%sCompressed", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_ENC)
            tsk_fprintf(hFile, "%sEncrypted", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_OFF)
            tsk_fprintf(hFile, "%sOffline", a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_NOIDX)
            tsk_fprintf(hFile, "%sNot Content Indexed",
                a++ == 0 ? "" : ", ");
        if (flags & NTFS_FNAME_FLAGS_IDXVIEW)
            tsk_fprintf(hFile, "%sIndex View", a++ == 0 ? "" : ", ");
        tsk_fprintf(hFile, "\n");


        name16 = (UTF16 *) & fname->name;
        name8 = (UTF8 *) name8buf;

        retVal =
            tsk_UTF16toUTF8(fs->endian, (const UTF16 **) &name16,
            (UTF16 *) ((uintptr_t) name16 +
                fname->nlen * 2),
            &name8,
            (UTF8 *) ((uintptr_t) name8 + NTFS_MAXNAMLEN_UTF8),
            TSKlenientConversion);
        if (retVal != TSKconversionOK) {
            if (tsk_verbose)
                tsk_fprintf(stderr,
                    "ntfs_istat: Error converting NTFS name in $FNAME to UTF8: %d",
                    retVal);
            *name8 = '\0';
        }
        /* Make sure it is NULL Terminated */
        else if ((uintptr_t) name8 >=
            (uintptr_t) name8buf + NTFS_MAXNAMLEN_UTF8)
            name8buf[NTFS_MAXNAMLEN_UTF8] = '\0';
        else
            *name8 = '\0';


        tsk_fprintf(hFile, "Name: %s\n", name8buf);

        tsk_fprintf(hFile,
            "Parent MFT Entry: %" PRIu64
            " \tSequence: %" PRIu16 "\n",
            (uint64_t) tsk_getu48(fs->endian, fname->par_ref),
            tsk_getu16(fs->endian, fname->par_seq));
        tsk_fprintf(hFile,
            "Allocated Size: %" PRIu64
            "   \tActual Size: %" PRIu64 "\n",
            tsk_getu64(fs->endian, fname->alloc_fsize),
            tsk_getu64(fs->endian, fname->real_fsize));
        /*
         * Times
         */

        /* Times - take it from fs_file->meta instead of redoing the work */

        if (sec_skew != 0) {
            tsk_fprintf(hFile, "\nAdjusted times:\n");

            tsk_fprintf(hFile, "Created:\t%s\n",
                        tsk_fs_time_to_str_subsecs(nt2unixtime(tsk_getu64(fs->endian, fname->crtime)) - sec_skew, nt2nano(tsk_getu64(fs->endian, fname->crtime)), timeBuf));
            tsk_fprintf(hFile, "File Modified:\t%s\n",
                        tsk_fs_time_to_str_subsecs(nt2unixtime(tsk_getu64(fs->endian, fname->mtime)) - sec_skew, nt2nano(tsk_getu64(fs->endian, fname->mtime)), timeBuf));
            tsk_fprintf(hFile, "MFT Modified:\t%s\n",
                        tsk_fs_time_to_str_subsecs(nt2unixtime(tsk_getu64(fs->endian, fname->ctime)) - sec_skew, nt2nano(tsk_getu64(fs->endian, fname->ctime)), timeBuf));
            tsk_fprintf(hFile, "Accessed:\t%s\n",
                        tsk_fs_time_to_str_subsecs(nt2unixtime(tsk_getu64(fs->endian, fname->atime)) - sec_skew, nt2nano(tsk_getu64(fs->endian, fname->atime)), timeBuf));

            tsk_fprintf(hFile, "\nOriginal times:\n");
        }

        tsk_fprintf(hFile, "Created:\t%s\n",
                    tsk_fs_time_to_str_subsecs(nt2unixtime(tsk_getu64(fs->endian, fname->crtime)), nt2nano(tsk_getu64(fs->endian, fname->crtime)), timeBuf));
        tsk_fprintf(hFile, "File Modified:\t%s\n",
                    tsk_fs_time_to_str_subsecs(nt2unixtime(tsk_getu64(fs->endian, fname->mtime)), nt2nano(tsk_getu64(fs->endian, fname->mtime)), timeBuf));
        tsk_fprintf(hFile, "MFT Modified:\t%s\n",
                    tsk_fs_time_to_str_subsecs(nt2unixtime(tsk_getu64(fs->endian, fname->ctime)), nt2nano(tsk_getu64(fs->endian, fname->ctime)), timeBuf));
        tsk_fprintf(hFile, "Accessed:\t%s\n",
                    tsk_fs_time_to_str_subsecs(nt2unixtime(tsk_getu64(fs->endian, fname->atime)), nt2nano(tsk_getu64(fs->endian, fname->atime)), timeBuf));
    }


    /* $OBJECT_ID Information */
    fs_attr = tsk_fs_attrlist_get(fs_file->meta->attr, (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_OBJID);
    if (fs_attr) {
        ntfs_attr_objid *objid = (ntfs_attr_objid *) fs_attr->rd.buf;
        uint64_t id1, id2;
        tsk_fprintf(hFile, "\n$OBJECT_ID Attribute Values:\n");
        id1 = tsk_getu64(fs->endian, objid->objid1);
        id2 = tsk_getu64(fs->endian, objid->objid2);
        tsk_fprintf(hFile,
            "Object Id: %.8" PRIx32 "-%.4" PRIx16
            "-%.4" PRIx16 "-%.4" PRIx16 "-%.4"
            PRIx16 "%.8" PRIx32 "\n",
            tsk_getu32(fs->endian, objid->objid1),
            tsk_getu16(fs->endian, objid->objid2),
            tsk_getu16(fs->endian, objid->objid3),
            tsk_getu16(TSK_BIG_ENDIAN, objid->objid4),
            tsk_getu16(TSK_BIG_ENDIAN, objid->objid5),
            tsk_getu32(TSK_BIG_ENDIAN, objid->objid6));

        /* The rest of the  fields do not always exist.  Check the attr size */
        if (fs_attr->size > 16) {
            id1 = tsk_getu64(fs->endian, objid->orig_volid1);
            id2 = tsk_getu64(fs->endian, objid->orig_volid2);
            tsk_fprintf(hFile,
                "Birth Volume Id: %.8" PRIx32 "-%.4"
                PRIx16 "-%.4" PRIx16 "-%.4" PRIx16
                "-%.12" PRIx64 "\n",
                (uint32_t) (id2 >> 32) & 0xffffffff,
                (uint16_t) (id2 >> 16) & 0xffff,
                (uint16_t) (id2 & 0xffff),
                (uint16_t) (id1 >> 48) & 0xffff,
                (uint64_t) (id1 & (uint64_t)
                    0x0000ffffffffffffULL));
        }

        if (fs_attr->size > 32) {
            id1 = tsk_getu64(fs->endian, objid->orig_objid1);
            id2 = tsk_getu64(fs->endian, objid->orig_objid2);
            tsk_fprintf(hFile,
                "Birth Object Id: %.8" PRIx32 "-%.4"
                PRIx16 "-%.4" PRIx16 "-%.4" PRIx16
                "-%.12" PRIx64 "\n",
                (uint32_t) (id2 >> 32) & 0xffffffff,
                (uint16_t) (id2 >> 16) & 0xffff,
                (uint16_t) (id2 & 0xffff),
                (uint16_t) (id1 >> 48) & 0xffff,
                (uint64_t) (id1 & (uint64_t)
                    0x0000ffffffffffffULL));
        }

        if (fs_attr->size > 48) {
            id1 = tsk_getu64(fs->endian, objid->orig_domid1);
            id2 = tsk_getu64(fs->endian, objid->orig_domid2);
            tsk_fprintf(hFile,
                "Birth Domain Id: %.8" PRIx32 "-%.4"
                PRIx16 "-%.4" PRIx16 "-%.4" PRIx16
                "-%.12" PRIx64 "\n",
                (uint32_t) (id2 >> 32) & 0xffffffff,
                (uint16_t) (id2 >> 16) & 0xffff,
                (uint16_t) (id2 & 0xffff),
                (uint16_t) (id1 >> 48) & 0xffff,
                (uint64_t) (id1 & (uint64_t)
                    0x0000ffffffffffffULL));
        }
    }

    /* Attribute List Information */
    fs_attr =
        tsk_fs_attrlist_get(fs_file->meta->attr,  (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_ATTRLIST);
    if (fs_attr) {
        char *buf;
        ntfs_attrlist *list;
        uintptr_t endaddr;
        TSK_FS_LOAD_FILE load_file;

        tsk_fprintf(hFile, "\n$ATTRIBUTE_LIST Attribute Values:\n");

        /* Get a copy of the attribute list stream  */
        load_file.total = load_file.left = (size_t) fs_attr->size;
        load_file.cur = load_file.base = buf =
            (char*) tsk_malloc((size_t) fs_attr->size);
        if (buf == NULL) {
            free(mft);
            return 1;
        }

        endaddr = (uintptr_t) buf + (uintptr_t) fs_attr->size;
        if (tsk_fs_attr_walk(fs_attr,
                TSK_FS_FILE_WALK_FLAG_NONE, tsk_fs_load_file_action, (void *) &load_file)) {
            tsk_fprintf(hFile, "error reading attribute list buffer\n");
            tsk_error_reset();
            goto egress;
        }

        /* this value should be zero, if not then we didn't read all of the
         * buffer
         */
        if (load_file.left > 0) {
            tsk_fprintf(hFile, "error reading attribute list buffer\n");
            goto egress;
        }

        /* Process the list & print the details */
        for (list = (ntfs_attrlist *) buf;
            (list) && ((uintptr_t) list < endaddr)
            && (tsk_getu16(fs->endian, list->len) > 0);
            list =
            (ntfs_attrlist *) ((uintptr_t) list + tsk_getu16(fs->endian,
                    list->len))) {
            tsk_fprintf(hFile,
                "Type: %" PRIu32 "-%" PRIu16 " \tMFT Entry: %" PRIu64
                " \tVCN: %" PRIu64 "\n", tsk_getu32(fs->endian,
                    list->type), tsk_getu16(fs->endian, list->id),
                (uint64_t) tsk_getu48(fs->endian, list->file_ref),
                tsk_getu64(fs->endian, list->start_vcn));
        }
      egress:
        free(buf);
    }

    /* Print all of the attributes */
    tsk_fprintf(hFile, "\nAttributes: \n");
    if (fs_file->meta->attr) {
        int cnt, i;

        // cycle through the attributes
        cnt = tsk_fs_file_attr_getsize(fs_file.get());
        for (i = 0; i < cnt; i++) {
            char type[512];

            const TSK_FS_ATTR *fs_attr =
                tsk_fs_file_attr_get_idx(fs_file.get(), i);
            if (!fs_attr)
                continue;

            if (ntfs_attrname_lookup(fs, fs_attr->type, type, 512)) {
                tsk_fprintf(hFile, "error looking attribute name\n");
                break;
            }

            /* print the layout if it is non-resident and not "special" */
            if (fs_attr->flags & TSK_FS_ATTR_NONRES) {
                NTFS_PRINT_ADDR print_addr;

                tsk_fprintf(hFile,
                    "Type: %s (%" PRIu32 "-%" PRIu16
                    ")   Name: %s   Non-Resident%s%s%s   size: %"
          PRIdOFF "  init_size: %" PRIdOFF "\n", type,
                    fs_attr->type, fs_attr->id,
                    (fs_attr->name) ? fs_attr->name : "N/A",
                    (fs_attr->flags & TSK_FS_ATTR_ENC) ? ", Encrypted" :
                    "",
                    (fs_attr->flags & TSK_FS_ATTR_COMP) ? ", Compressed" :
                    "",
                    (fs_attr->flags & TSK_FS_ATTR_SPARSE) ? ", Sparse" :
                    "", fs_attr->size, fs_attr->nrd.initsize);
                if (istat_flags & TSK_FS_ISTAT_RUNLIST) {
                    if (tsk_fs_attr_print(fs_attr, hFile)) {
                        tsk_fprintf(hFile, "\nError creating run lists\n");
                        tsk_error_print(hFile);
                        tsk_error_reset();
                    }
                }
                else {
                    print_addr.idx = 0;
                    print_addr.hFile = hFile;
                    if (tsk_fs_file_walk_type(fs_file.get(), fs_attr->type,
                        fs_attr->id,
                        (TSK_FS_FILE_WALK_FLAG_ENUM)
                        (TSK_FS_FILE_WALK_FLAG_AONLY |
                            TSK_FS_FILE_WALK_FLAG_SLACK),
                        print_addr_act, (void *)&print_addr)) {
                        tsk_fprintf(hFile, "\nError walking file\n");
                        tsk_error_print(hFile);
                        tsk_error_reset();
                    }
                    if (print_addr.idx != 0)
                        tsk_fprintf(hFile, "\n");
                }

            }
            else {
                tsk_fprintf(hFile,
                    "Type: %s (%" PRIu32 "-%" PRIu16
                    ")   Name: %s   Resident%s%s%s   size: %"
          PRIdOFF "\n", type, fs_attr->type,
                    fs_attr->id,
                    (fs_attr->name) ? fs_attr->name : "N/A",
                    (fs_attr->flags & TSK_FS_ATTR_ENC) ? ", Encrypted"
                    : "",
                    (fs_attr->flags & TSK_FS_ATTR_COMP) ?
                    ", Compressed" : "",
                    (fs_attr->flags & TSK_FS_ATTR_SPARSE) ? ", Sparse" :
                    "", fs_attr->size);

            }
        }
    }

    free(mft);
    return 0;
}



/* JOURNAL CODE - MOVE TO NEW FILE AT SOME POINT */

static uint8_t
ntfs_jopen(
  [[maybe_unused]] TSK_FS_INFO * fs,
  [[maybe_unused]] TSK_INUM_T inum)
{
    tsk_error_reset();
    tsk_error_set_errno(TSK_ERR_FS_UNSUPFUNC);
    tsk_error_set_errstr("NTFS Journal is not yet supported\n");
    return 1;
}

static uint8_t
ntfs_jentry_walk(
  [[maybe_unused]] TSK_FS_INFO * fs,
  [[maybe_unused]] int flags,
  [[maybe_unused]] TSK_FS_JENTRY_WALK_CB a_action,
  [[maybe_unused]] void *ptr)
{
    tsk_error_reset();
    tsk_error_set_errno(TSK_ERR_FS_UNSUPFUNC);
    tsk_error_set_errstr("NTFS Journal is not yet supported\n");
    return 1;
}

static uint8_t
ntfs_jblk_walk(
  [[maybe_unused]] TSK_FS_INFO * fs,
  [[maybe_unused]] TSK_DADDR_T start,
  [[maybe_unused]] TSK_DADDR_T end,
  [[maybe_unused]] int flags,
  [[maybe_unused]] TSK_FS_JBLK_WALK_CB a_action,
  [[maybe_unused]] void *ptr)
{
    tsk_error_reset();
    tsk_error_set_errno(TSK_ERR_FS_UNSUPFUNC);
    tsk_error_set_errstr("NTFS Journal is not yet supported\n");
    return 1;
}


static TSK_FS_ATTR_TYPE_ENUM
ntfs_get_default_attr_type(const TSK_FS_FILE * a_file)
{
    if ((a_file == NULL) || (a_file->meta == NULL))
        return TSK_FS_ATTR_TYPE_DEFAULT;

    /* Use DATA for files and IDXROOT for dirs */
    if (TSK_FS_IS_DIR_META(a_file->meta->type))
        return TSK_FS_ATTR_TYPE_NTFS_IDXROOT;
    else
        return TSK_FS_ATTR_TYPE_NTFS_DATA;

}


static void
ntfs_close(TSK_FS_INFO * fs)
{
    NTFS_INFO *ntfs = (NTFS_INFO *) fs;

    if (fs == NULL)
        return;

#if TSK_USE_SID
    free(ntfs->sii_data.buffer);
    ntfs->sii_data.buffer = NULL;

    free(ntfs->sds_data.buffer);
    ntfs->sds_data.buffer = NULL;

#endif

    fs->tag = 0;
    free(ntfs->fs);
    tsk_fs_attr_run_free(ntfs->bmap);
    free(ntfs->bmap_buf);
    tsk_fs_file_close(ntfs->mft_file);

    if (ntfs->orphan_map)
        ntfs_orphan_map_free(ntfs);

    tsk_deinit_lock(&ntfs->lock);
    tsk_deinit_lock(&ntfs->orphan_map_lock);
#if TSK_USE_SID
    tsk_deinit_lock(&ntfs->sid_lock);
#endif

    tsk_fs_free(fs);
}

/**
 * Check if the boot format matches that produced in KAPE VHDs
 * that are missing the 0x55AA marker.
 * Will also set the endianness.
 *
 * @param ntfs_info File system info
 * @returns 0 if format appeares valid, 1 otherwise
 */
static int
process_kape_boot_format(NTFS_INFO* ntfs_info) {

    // Check that we have a VHD
    if (ntfs_info->fs_info.img_info->itype != TSK_IMG_TYPE_VHD_VHD) {
        return 1;
    }

    // Check that expected name is present
    if (strncmp(ntfs_info->fs->oemname, "NTFS    ", 8) != 0) {
        return 1;
    }

    // Check endianness using the sector size
    uint16_t ssize = tsk_getu16(TSK_LIT_ENDIAN, ntfs_info->fs->ssize);
    if ((ssize != 0) && (ssize % 512 == 0)) {
        ntfs_info->fs_info.endian = TSK_LIT_ENDIAN;
        return 0;
    }
    ssize = tsk_getu16(TSK_BIG_ENDIAN, ntfs_info->fs->ssize);
    if ((ssize != 0) && (ssize % 512 == 0)) {
        ntfs_info->fs_info.endian = TSK_BIG_ENDIAN;
        return 0;
    }

    return 1;
}

/**
 * Open part of a disk image as an NTFS file system.
 *
 * @param img_info Disk image to analyze
 * @param offset Byte offset where NTFS file system starts
 * @param ftype Specific type of NTFS file system
 * @param a_pass (Optional) bitlocker password
 * @param test NOT USED
 * @returns NULL on error or if data is not an NTFS file system
 */
TSK_FS_INFO *
ntfs_open(
  TSK_IMG_INFO * img_info,
  TSK_OFF_T offset,
  TSK_FS_TYPE_ENUM ftype,
  const char* a_pass,
  [[maybe_unused]] uint8_t test)
{
    const char *myname = "ntfs_open";
    NTFS_INFO *ntfs = NULL;
    TSK_FS_INFO *fs = NULL;
    unsigned int len = 0;
    ssize_t cnt = 0;

    // clean up any error messages that are lying around
    tsk_error_reset();

    if (TSK_FS_TYPE_ISNTFS(ftype) == 0) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("Invalid FS type in ntfs_open");
        return NULL;
    }

    if (img_info->sector_size == 0) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_ARG);
        tsk_error_set_errstr("ntfs_open: sector size is 0");
        return NULL;
    }

    uint32_t csize;

    if ((ntfs = (NTFS_INFO *) tsk_fs_malloc(sizeof(*ntfs))) == NULL) {
        goto on_error;
    }
    fs = &(ntfs->fs_info);

    fs->ftype = TSK_FS_TYPE_NTFS;
    fs->duname = "Cluster";
    fs->flags = TSK_FS_INFO_FLAG_HAVE_SEQ;
    fs->tag = TSK_FS_INFO_TAG;

    fs->img_info = img_info;
    fs->offset = offset;

    ntfs->loading_the_MFT = 0;
    ntfs->bmap = NULL;
    ntfs->bmap_buf = NULL;

    // Check for any volume encryption and initialize if found.
    // A non-zero value will only be returned if we are very confident encryption was found
    // but encountered an error and should not continue trying to open the volume.
    // In this case we should also have a specific error to get back to the user, such as reporting an incorrect password.
    if (0 != handleVolumeEncryption((TSK_FS_INFO*)ntfs, a_pass)) {
        goto on_error;
    }

    /* Read the boot sector */
    len = roundup(sizeof(ntfs_sb), img_info->sector_size);
    ntfs->fs = (ntfs_sb *) tsk_malloc(len);
    if (ntfs->fs == NULL) {
        goto on_error;
    }

    cnt = tsk_fs_read(fs, (TSK_OFF_T) 0, (char *) ntfs->fs, len);
    if (cnt != len) {
        if (cnt >= 0) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_READ);
        }
        tsk_error_set_errstr2("%s: Error reading boot sector.", myname);
        goto on_error;
    }

    /* Check the magic value */
    if (tsk_fs_guessu16(fs, ntfs->fs->magic, NTFS_FS_MAGIC)) {
        if (process_kape_boot_format(ntfs)) {
            tsk_error_reset();
            tsk_error_set_errno(TSK_ERR_FS_MAGIC);
            tsk_error_set_errstr("Not a NTFS file system (magic)");
            if (tsk_verbose)
                fprintf(stderr, "ntfs_open: Incorrect NTFS magic\n");
            goto on_error;
        }
    }


    /*
     * block calculations : although there are no blocks in ntfs,
     * we are using a cluster as a "block"
     */

    ntfs->ssize_b = tsk_getu16(fs->endian, ntfs->fs->ssize);
    if ((ntfs->ssize_b == 0) || (ntfs->ssize_b % 512)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_MAGIC);
        tsk_error_set_errstr
            ("Not a NTFS file system (invalid sector size %d))",
            ntfs->ssize_b);
        if (tsk_verbose)
            fprintf(stderr, "ntfs_open: invalid sector size: %d\n",
                ntfs->ssize_b);
        goto on_error;
    }

    csize = ntfs->fs->csize;
    if (ntfs->fs->csize > 0x80) {
      csize = 1 << -(int8_t)ntfs->fs->csize;
    }

    if ((csize != 0x01) &&
      (csize != 0x02) &&
      (csize != 0x04) &&
      (csize != 0x08) &&
      (csize != 0x10) &&
      (csize != 0x20) &&
      (csize != 0x40) &&
      (csize != 0x80) &&
      (csize != 0x100) &&
      (csize != 0x200) &&
      (csize != 0x400) &&
      (csize != 0x800) &&
      (csize != 0x1000)
      ) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_MAGIC);
        tsk_error_set_errstr
            ("Not a NTFS file system (invalid cluster size %d)",
            ntfs->fs->csize);
        if (tsk_verbose)
            fprintf(stderr, "ntfs_open: invalid cluster size: %d\n",
                ntfs->fs->csize);
        goto on_error;
    }

    ntfs->csize_b = csize * ntfs->ssize_b;
    fs->first_block = 0;
    /* This field is defined as 64-bits but according to the
     * NTFS drivers in Linux, old Windows versions used only 32-bits
     */
    fs->block_count =
        (TSK_DADDR_T) tsk_getu64(fs->endian,
        ntfs->fs->vol_size_s) / csize;
    if (fs->block_count == 0) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_MAGIC);
        tsk_error_set_errstr("Not a NTFS file system (volume size is 0)");
        if (tsk_verbose)
            fprintf(stderr, "ntfs_open: invalid volume size: 0\n");
        goto on_error;
    }

    fs->last_block = fs->last_block_act = fs->block_count - 1;
    fs->block_size = ntfs->csize_b;
    fs->dev_bsize = img_info->sector_size;

    // determine the last block we have in this image
    if ((TSK_DADDR_T) ((img_info->size - offset) / fs->block_size) <
        fs->block_count)
        fs->last_block_act =
            (img_info->size - offset) / fs->block_size - 1;

    ntfs->mft_rsize_b = 0;
    if (ntfs->fs->mft_rsize_c > 0) {
        ntfs->mft_rsize_b = ntfs->fs->mft_rsize_c * ntfs->csize_b;
    }
    else if (ntfs->fs->mft_rsize_c > -32) {
        /* if the mft_rsize_c is not > 0, then it is -log2(rsize_b) */
        ntfs->mft_rsize_b = 1 << -ntfs->fs->mft_rsize_c;
    }

    if ((ntfs->mft_rsize_b == 0) || (ntfs->mft_rsize_b % 512)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_MAGIC);
        tsk_error_set_errstr
            ("Not a NTFS file system (invalid MFT entry size)");
        if (tsk_verbose)
            fprintf(stderr, "ntfs_open: invalid MFT entry size\n");
        goto on_error;
    }

    ntfs->idx_rsize_b = 0;
    if (ntfs->fs->idx_rsize_c > 0) {
        ntfs->idx_rsize_b = ntfs->fs->idx_rsize_c * ntfs->csize_b;
    }
    else if (ntfs->fs->idx_rsize_c > -32) {
        /* if the idx_rsize_c is not > 0, then it is -log2(rsize_b) */
        ntfs->idx_rsize_b = 1 << -ntfs->fs->idx_rsize_c;
    }

    if ((ntfs->idx_rsize_b == 0) || (ntfs->idx_rsize_b % 512)) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_MAGIC);
        tsk_error_set_errstr
            ("Not a NTFS file system (invalid idx record size %d)",
            ntfs->idx_rsize_b);
        if (tsk_verbose)
            fprintf(stderr, "ntfs_open: invalid idx record size %d\n",
                ntfs->idx_rsize_b);
        goto on_error;
    }

    ntfs->root_mft_addr =
        tsk_getu64(fs->endian, ntfs->fs->mft_clust) * ntfs->csize_b;
    if (tsk_getu64(fs->endian, ntfs->fs->mft_clust) > fs->last_block) {
        tsk_error_reset();
        tsk_error_set_errno(TSK_ERR_FS_MAGIC);
        tsk_error_set_errstr
            ("Not a NTFS file system (invalid starting MFT clust)");
        if (tsk_verbose)
            fprintf(stderr, "ntfs_open: invalid starting MFT cluster\n");
        goto on_error;
    }

    /*
     * Set the function pointers (before we start calling internal functions)
     */
    fs->inode_walk = ntfs_inode_walk;
    fs->block_walk = ntfs_block_walk;
    fs->block_getflags = ntfs_block_getflags;

    fs->get_default_attr_type = ntfs_get_default_attr_type;
    fs->load_attrs = ntfs_load_attrs;

    fs->file_add_meta = ntfs_inode_lookup;
    fs->dir_open_meta = ntfs_dir_open_meta;
    fs->fsstat = ntfs_fsstat;
    fs->fscheck = ntfs_fscheck;
    fs->istat = ntfs_istat;
    fs->close = ntfs_close;
    fs->name_cmp = ntfs_name_cmp;

    fs->fread_owner_sid = ntfs_file_get_sidstr;
    fs->jblk_walk = ntfs_jblk_walk;
    fs->jentry_walk = ntfs_jentry_walk;
    fs->jopen = ntfs_jopen;
    fs->journ_inum = 0;



    // set up locks
    tsk_init_lock(&ntfs->lock);
    tsk_init_lock(&ntfs->orphan_map_lock);
#if TSK_USE_SID
    tsk_init_lock(&ntfs->sid_lock);
#endif

    /*
     * inode
     */

    fs->root_inum = NTFS_ROOTINO;
    fs->first_inum = NTFS_FIRSTINO;
    fs->last_inum = NTFS_LAST_DEFAULT_INO;
    ntfs->mft_data = NULL;

    /* load the data run for the MFT table into ntfs->mft */
    ntfs->loading_the_MFT = 1;
    if ((ntfs->mft_file =
            tsk_fs_file_open_meta(fs, NULL, NTFS_MFT_MFT)) == NULL) {
        if (tsk_verbose)
            fprintf(stderr,
                "ntfs_open: Error opening $MFT (%s)\n", tsk_error_get());
        goto on_error;
    }

    /* cache the data attribute
     *
     * This will likely be done already by proc_attrseq, but this
     * should be quick
     */
    ntfs->mft_data =
        tsk_fs_attrlist_get(ntfs->mft_file->meta->attr, (TSK_FS_ATTR_TYPE_ENUM) NTFS_ATYPE_DATA);
    if (!ntfs->mft_data) {
        tsk_error_errstr2_concat(" - Data Attribute not found in $MFT");
        if (tsk_verbose)
            fprintf(stderr,
                "ntfs_open: Data attribute not found in $MFT (%s)\n",
                tsk_error_get());
        goto on_error;
    }

    /* Get the inode count based on the table size */
    fs->inum_count = ntfs->mft_data->size / ntfs->mft_rsize_b + 1;      // we are adding 1 in this calc to account for Orphans directory
    fs->last_inum = fs->inum_count - 1;

    /* reset the flag that we are no longer loading $MFT */
    ntfs->loading_the_MFT = 0;

    /* Volume ID */
    for (fs->fs_id_used = 0; fs->fs_id_used < 8; fs->fs_id_used++) {
        fs->fs_id[fs->fs_id_used] = ntfs->fs->serial[fs->fs_id_used];
    }

    /* load the version of the file system */
    if (ntfs_load_ver(ntfs)) {
        if (tsk_verbose)
            fprintf(stderr,
                "ntfs_open: Error loading file system version ((%s)\n",
                tsk_error_get());
        goto on_error;
    }

    /* load the data block bitmap data run into ntfs_info */
    if (ntfs_load_bmap(ntfs)) {
        if (tsk_verbose)
            fprintf(stderr, "ntfs_open: Error loading block bitmap (%s)\n",
                tsk_error_get());
        goto on_error;
    }

    /* load the SID data into ntfs_info ($Secure - $SDS, $SDH, $SII */


#if TSK_USE_SID
    if (ntfs_load_secure(ntfs)) {
        if (tsk_verbose)
            fprintf(stderr, "ntfs_open: Error loading Secure Info (%s)\n",
                tsk_error_get());
        goto on_error;
    }
#endif

    // initialize the caches
    ntfs->attrdef = NULL;
    ntfs->orphan_map = NULL;

    // initialize the number of allocated files
    ntfs->alloc_file_count = 0;

    if (tsk_verbose) {
        tsk_fprintf(stderr,
            "ssize: %" PRIu16
            " csize: %d serial: %" PRIx64 "\n",
            tsk_getu16(fs->endian, ntfs->fs->ssize),
            csize, tsk_getu64(fs->endian, ntfs->fs->serial));
        tsk_fprintf(stderr,
            "mft_rsize: %d idx_rsize: %d vol: %d mft: %"
            PRIu64 " mft_mir: %" PRIu64 "\n",
            ntfs->mft_rsize_b, ntfs->idx_rsize_b,
            (int) fs->block_count, tsk_getu64(fs->endian,
                ntfs->fs->mft_clust), tsk_getu64(fs->endian,
                ntfs->fs->mftm_clust));
    }
    return fs;

on_error:
    ntfs_close(fs);
    return NULL;
}

Coverage Report

Created: 2025-10-12 06:40