/*
** The Sleuth Kit
**
** This software is subject to the IBM Public License ver. 1.0,
** which was displayed prior to download and is included in the readme.txt
** file accompanying the Sleuth Kit files.  It may also be requested from:
** Crucial Security Inc.
** 14900 Conference Center Drive
** Chantilly, VA 20151
**
** Wyatt Banks [wbanks@crucialsecurity.com]
** Copyright (c) 2005 Crucial Security Inc.  All rights reserved.
**
** Brian Carrier [carrier@sleuthkit.org]
** Copyright (c) 2003-2005 Brian Carrier.  All rights reserved
**
** Copyright (c) 1997,1998,1999, International Business Machines
** Corporation and others. All Rights Reserved.
*/

/* TCT
 * LICENSE
 *      This software is distributed under the IBM Public License.
 * AUTHOR(S)
 *      Wietse Venema
 *      IBM T.J. Watson Research
 *      P.O. Box 704
 *      Yorktown Heights, NY 10598, USA
 --*/

/*
** You may distribute the Sleuth Kit, or other software that incorporates
** part of all of the Sleuth Kit, in object code form under a license agreement,
** provided that:
** a) you comply with the terms and conditions of the IBM Public License
**    ver 1.0; and
** b) the license agreement
**     i) effectively disclaims on behalf of all Contributors all warranties
**        and conditions, express and implied, including warranties or
**        conditions of title and non-infringement, and implied warranties
**        or conditions of merchantability and fitness for a particular
**        purpose.
**    ii) effectively excludes on behalf of all Contributors liability for
**        damages, including direct, indirect, special, incidental and
**        consequential damages such as lost profits.
**   iii) states that any provisions which differ from IBM Public License
**        ver. 1.0 are offered by that Contributor alone and not by any
**        other party; and
**    iv) states that the source code for the program is available from you,
**        and informs licensees how to obtain it in a reasonable manner on or
**        through a medium customarily used for software exchange.
**
** When the Sleuth Kit or other software that incorporates part or all of
** the Sleuth Kit is made available in source code form:
**     a) it must be made available under IBM Public License ver. 1.0; and
**     b) a copy of the IBM Public License ver. 1.0 must be included with
**        each copy of the program.
*/

#include "fs_tools_i.h"
#include "iso9660.h"

static unsigned int depth = 0;

#define DIR_STRSZ	4096
static char dirs[DIR_STRSZ];
#define MAX_DEPTH	128
static char *didx[MAX_DEPTH];

/* iso9660_dent_walk - walk directory entries starting with inode 'inum'.
 *	flags - TSK_FS_DENT_FLAG_RECURSE
 */
uint8_t
iso9660_dent_walk(TSK_FS_INFO * fs, INUM_T inum,
    TSK_FS_DENT_FLAG_ENUM flags, TSK_FS_DENT_TYPE_WALK_CB action,
    void *ptr)
{
    ISO_INFO *iso = (ISO_INFO *) fs;
    TSK_FS_DENT *fs_dent;
    char *buf;                  /* temp storage for directory extent */
    int length = 0;             /* size of directory extent */
    iso9660_dentry *dd;         /* directory descriptor */
    in_node *in;
    off_t offs;                 /* where we are reading in the file */
    int retval;
    SSIZE_T cnt;

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

    if (inum < fs->first_inum || inum > fs->last_inum) {
        tsk_error_reset();
        tsk_errno = TSK_ERR_FS_WALK_RNG;
        snprintf(tsk_errstr, TSK_ERRSTR_L,
            "iso9660_dent_walk: inode value: %" PRIuINUM "\n", inum);
        return 1;
    }


    if (tsk_verbose)
        tsk_fprintf(stderr,
            "iso9660_dent_walk: Processing directory %lu\n", (ULONG) inum);

    if ((fs_dent = tsk_fs_dent_alloc(ISO9660_MAXNAMLEN, 0)) == NULL)
        return 1;

    if (iso9660_dinode_load(iso, inum))
        return 1;

    /* walking a directory */
    if ((iso->dinode->dr.flags & ISO9660_FLAG_DIR) == ISO9660_FLAG_DIR) {
        TSK_LIST *list_seen = NULL;

        /* calculate directory extent location */
        offs =
            (off_t) (fs->block_size *
            parseu32(fs, iso->dinode->dr.ext_loc));

        /* read directory extent into memory */
        length = parseu32(fs, iso->dinode->dr.data_len);

        if ((buf = tsk_malloc(length)) == NULL) {
            return 1;
        }
        cnt = tsk_fs_read_random(fs, buf, length, offs);
        if (cnt != length) {
            if (cnt != -1) {
                tsk_error_reset();
                tsk_errno = TSK_ERR_FS_READ;
                tsk_errstr[0] = '\0';
            }
            snprintf(tsk_errstr2, TSK_ERRSTR_L, "iso_dent_walk:");
            return 1;
        }

        dd = (iso9660_dentry *) buf;

        /* handle "." entry */
        fs_dent->inode = inum;
        strcpy(fs_dent->name, ".");

        fs_dent->path = dirs;
        fs_dent->pathdepth = depth;
        fs_dent->fsi = fs->inode_lookup(fs, fs_dent->inode);
        fs_dent->ent_type = TSK_FS_DENT_TYPE_DIR;
        fs_dent->flags = TSK_FS_DENT_FLAG_ALLOC;

        if (flags & TSK_FS_DENT_FLAG_ALLOC) {
            retval = action(fs, fs_dent, ptr);
            if (retval == TSK_WALK_ERROR) {
                tsk_fs_dent_free(fs_dent);
                return 1;
            }
            else if (retval == TSK_WALK_STOP) {
                tsk_fs_dent_free(fs_dent);
                return 0;
            }
        }

        length -= dd->length;

        dd = (iso9660_dentry *) ((char *) dd + dd->length);

        /* handle ".." entry */
        in = iso->in;

        while (in
            && (parseu32(fs, in->inode.dr.ext_loc) !=
                parseu32(fs, dd->ext_loc)))
            in = in->next;

        fs_dent->inode = in->inum;
        strcpy(fs_dent->name, "..");

        fs_dent->path = dirs;
        fs_dent->pathdepth = depth;
        fs_dent->fsi = fs->inode_lookup(fs, fs_dent->inode);
        fs_dent->ent_type = TSK_FS_DENT_TYPE_DIR;
        fs_dent->flags = TSK_FS_DENT_FLAG_ALLOC;

        if (flags & TSK_FS_DENT_FLAG_ALLOC) {
            retval = action(fs, fs_dent, ptr);
            if (retval == TSK_WALK_ERROR) {
                tsk_fs_dent_free(fs_dent);
                return 1;
            }
            else if (retval == TSK_WALK_STOP) {
                tsk_fs_dent_free(fs_dent);
                return 0;
            }
        }

        length -= dd->length;

        dd = (iso9660_dentry *) ((char *) dd + dd->length);

        /* for each directory descriptor in it: */
        while (length > sizeof(iso9660_dentry)) {
            if (dd->length) {
                int retval;
                int i;
                /* print out info on what was in extent */
                in = iso->in;
                while (parseu32(fs, in->inode.dr.ext_loc) !=
                    parseu32(fs, dd->ext_loc))
                    in = in->next;

                fs_dent->inode = in->inum;
                strcpy(fs_dent->name, in->inode.fn);

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


                fs_dent->path = dirs;
                fs_dent->pathdepth = depth;
                fs_dent->fsi = fs->inode_lookup(fs, fs_dent->inode);
                if (dd->flags & ISO9660_FLAG_DIR)
                    fs_dent->ent_type = TSK_FS_DENT_TYPE_DIR;
                else
                    fs_dent->ent_type = TSK_FS_DENT_TYPE_REG;
                fs_dent->flags = TSK_FS_DENT_FLAG_ALLOC;

                if (flags & TSK_FS_DENT_FLAG_ALLOC) {
                    retval = action(fs, fs_dent, ptr);
                    if (retval == TSK_WALK_ERROR) {
                        tsk_fs_dent_free(fs_dent);
                        tsk_list_free(list_seen);
                        list_seen = NULL;
                        return 1;
                    }
                    else if (retval == TSK_WALK_STOP) {
                        tsk_fs_dent_free(fs_dent);
                        tsk_list_free(list_seen);
                        list_seen = NULL;
                        return 0;
                    }
                }

                if ((dd->flags & ISO9660_FLAG_DIR)
                    && (flags & TSK_FS_DENT_FLAG_RECURSE)) {
                    int depth_added = 0;

                    /* Make sure we do not get into an infinite loop */
                    if (0 == tsk_list_find(list_seen, fs_dent->inode)) {
                        if (tsk_list_add(&list_seen, fs_dent->inode)) {
                            tsk_fs_dent_free(fs_dent);
                            tsk_list_free(list_seen);
                            list_seen = NULL;
                            return -1;
                        }


                        if ((depth < MAX_DEPTH) &&
                            (DIR_STRSZ >
                                strlen(dirs) + strlen(fs_dent->name))) {
                            didx[depth] = &dirs[strlen(dirs)];
                            strncpy(didx[depth], fs_dent->name,
                                DIR_STRSZ - strlen(dirs));
                            strncat(dirs, "/", DIR_STRSZ);
                            depth_added = 1;
                        }
                        depth++;
                        if (iso9660_dent_walk(fs, in->inum, flags, action,
                                ptr)) {
                            /* If the directory could not be loaded,
                             * then move on */
                            if (tsk_verbose) {
                                tsk_fprintf(stderr,
                                    "iso_dent_parse_block: error reading directory: %"
                                    PRIuINUM "\n", in->inum);
                                tsk_error_print(stderr);
                            }
                            tsk_error_reset();
                        }

                        depth--;
                        if (depth_added)
                            *didx[depth] = '\0';
                    }
                }

                length -= dd->length;

                dd = (iso9660_dentry *) ((char *) dd + dd->length);
                /* we need to look for files past the next NULL we discover, in case
                 * directory has a hole in it (this is common) */
            }
            else {
                char *a, *b;
                length -= sizeof(iso9660_dentry);

                /* find next non-zero byte and we'll start over there */

                a = (char *) dd;
                b = a + sizeof(iso9660_dentry);

                while ((*a == 0) && (a != b))
                    a++;

                if (a != b) {
                    length += (int) (b - a);
                    dd = (iso9660_dentry *) ((char *) dd +
                        (sizeof(iso9660_dentry) - (int) (b - a)));
                }
            }
        }

        free(buf);
        tsk_list_free(list_seen);
        list_seen = NULL;
        /* regular file */
    }
    tsk_fs_dent_free(fs_dent);
    return 0;
}