fs/smbsrv/smb_odir.c

	smb_odir.c revision cb174861876aea6950a7ab4ce944aff84b1914cd
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*
 * General Structures Layout
 * -------------------------
 *
 * This is a simplified diagram showing the relationship between most of the
 * main structures.
 *
 * +-------------------+
 * |     SMB_INFO      |
 * +-------------------+
 *          |
 *          |
 *          v
 * +-------------------+       +-------------------+      +-------------------+
 * |     SESSION       |<----->|     SESSION       |......|      SESSION      |
 * +-------------------+       +-------------------+      +-------------------+
 *          |
 *          |
 *          v
 * +-------------------+       +-------------------+      +-------------------+
 * |       USER        |<----->|       USER        |......|       USER        |
 * +-------------------+       +-------------------+      +-------------------+
 *          |
 *          |
 *          v
 * +-------------------+       +-------------------+      +-------------------+
 * |       TREE        |<----->|       TREE        |......|       TREE        |
 * +-------------------+       +-------------------+      +-------------------+
 *      |         |
 *      |         |
 *      |         v
 *      |     +-------+       +-------+      +-------+
 *      |     | OFILE |<----->| OFILE |......| OFILE |
 *      |     +-------+       +-------+      +-------+
 *      |
 *      |
 *      v
 *  +-------+       +------+      +------+
 *  | ODIR  |<----->| ODIR |......| ODIR |
 *  +-------+       +------+      +------+
 *
 *
 * Odir State Machine
 * ------------------
 *
 *    +-------------------------+
 *    |  SMB_ODIR_STATE_OPEN    |<----------- open / creation
 *    +-------------------------+
 *      |            ^
 *      | (first)    | (last)
 *      | lookup     | release
 *      v            |
 *    +-------------------------+
 *    | SMB_ODIR_STATE_IN_USE   |----
 *    +-------------------------+   | lookup / release / read
 *      |                ^-------
 *      | close
 *      |
 *      v
 *    +-------------------------+
 *    | SMB_ODIR_STATE_CLOSING  |----
 *    +-------------------------+   | close / release / read
 *      |                ^-------
 *      | (last) release
 *      |
 *      v
 *    +-------------------------+
 *    | SMB_ODIR_STATE_CLOSED   |----------> deletion
 *    +-------------------------+
 *
 *
 * SMB_ODIR_STATE_OPEN
 * - the odir exists in the list of odirs of its tree
 * - lookup is valid in this state. It will place a hold on the odir
 *   by incrementing the reference count and the odir will transition
 *   to SMB_ODIR_STATE_IN_USE
 * - read/close/release not valid in this state
 *
 * SMB_ODIR_STATE_IN_USE
 * - the odir exists in the list of odirs of its tree.
 * - lookup is valid in this state. It will place a hold on the odir
 *   by incrementing the reference count.
 * - if the last hold is released the odir will transition
 *   back to SMB_ODIR_STATE_OPEN
 * - if a close is received the odir will transition to
 *   SMB_ODIR_STATE_CLOSING.
 *
 * SMB_ODIR_STATE_CLOSING
 * - the odir exists in the list of odirs of its tree.
 * - lookup will fail in this state.
 * - when the last hold is released the odir will transition
 *   to SMB_ODIR_STATE_CLOSED.
 *
 * SMB_ODIR_STATE_CLOSED
 * - the odir exists in the list of odirs of its tree.
 * - there are no users of the odir (refcnt == 0)
 * - the odir is being removed from the tree's list and deleted.
 * - lookup will fail in this state.
 * - read/close/release not valid in this state
 *
 * Comments
 * --------
 *    The state machine of the odir structures is controlled by 3 elements:
 *      - The list of odirs of the tree it belongs to.
 *      - The mutex embedded in the structure itself.
 *      - The reference count.
 *
 *    There's a mutex embedded in the odir structure used to protect its fields
 *    and there's a lock embedded in the list of odirs of a tree. To
 *    increment or to decrement the reference count the mutex must be entered.
 *    To insert the odir into the list of odirs of the tree and to remove
 *    the odir from it, the lock must be entered in RW_WRITER mode.
 *
 *    In order to avoid deadlocks, when both (mutex and lock of the odir
 *    list) have to be entered, the lock must be entered first.
 *
 *
 * Odir Interface
 * ---------------
 * odid = smb_odir_open(pathname)
 *  Create an odir representing the directory specified in pathname and
 *  add it into the tree's list of odirs.
 *  Return an identifier (odid) uniquely identifying the created odir.
 *
 * smb_odir_openat(smb_node_t *unode)
 *  Create an odir representing the extended attribute directory
 *  associated with the file (or directory) represented by unode
 *  and add it into the tree's list of odirs.
 *  Return an identifier (odid) uniquely identifying the created odir.
 *
 * smb_odir_t *odir = smb_tree_lookup_odir(odid)
 *  Find the odir corresponding to the specified odid in the tree's
 *  list of odirs. Place a hold on the odir.
 *
 * smb_odir_read(..., smb_odirent_t *odirent)
 *  Find the next directory entry in the odir and return it in odirent.
 *
 * smb_odir_read_fileinfo(..., smb_fileinfo_t *)
 *  Find the next directory entry in the odir. Return the details of
 *  the directory entry in smb_fileinfo_t. (See odir internals below)
 *
 * smb_odir_read_streaminfo(..., smb_streaminfo_t *)
 *  Find the next named stream entry in the odir. Return the details of
 *  the named stream in smb_streaminfo_t.
 *
 * smb_odir_close(smb_odir_t *odir)
 *  Close the odir.
 *  The caller of close must have a hold on the odir being closed.
 *  The hold should be released after closing.
 *
 * smb_odir_release(smb_odir_t *odir)
 *  Release the hold on the odir, obtained by lookup.
 *
 *
 * Odir Internals
 * --------------
 * The odir object represent an open directory search. Each read operation
 * provides the caller with a structure containing information  pertaining
 * to the next directory entry that matches the search criteria, namely
 * the filename or match pattern and, in the case of smb_odir_read_fileinfo(),
 * the search attributes.
 *
 * The odir maintains a buffer (d_buf) of directory entries read from
 * the filesystem via a vop_readdir. The buffer is populated when a read
 * request (smb_odir_next_odirent) finds that the buffer is empty or that
 * the end of the buffer has been reached, and also when a new client request
 * (find next) begins.
 *
 * The data in d_buf (that which is returned from the file system) can
 * be in one of two formats. If the file system supports extended directory
 * entries we request that the data be returned as edirent_t structures. If
 * it does not the data will be returned as dirent64_t structures. For
 * convenience, when the next directory entry is read from d_buf by
 * smb_odir_next_odirent it is translated into an smb_odirent_t.
 *
 * smb_odir_read_fileinfo
 * The processing required to obtain the information to populate the caller's
 * smb_fileinfo_t differs depending upon whether the directory search is for a
 * single specified filename or for multiple files matching a search pattern.
 * Thus smb_odir_read_fileinfo uses two static functions:
 * smb_odir_single_fileinfo - obtains the smb_fileinfo_t info for the single
 * filename as specified in smb_odir_open request.
 * smb_odir_wildcard_fileinfo - obtains the smb_fileinfo_t info for the filename
 * returned from the smb_odir_next_odirent. This is called in a loop until
 * an entry matching the search criteria is found or no more entries exist.
 *
 * If a directory entry is a VLNK, the name returned in the smb_fileinfo_t
 * is the name of the directory entry but the attributes are the attribites
 * of the file that is the target of the link. If the link target cannot
 * be found the attributes returned are the attributes of the link itself.
 *
 * smb_odir_read_streaminfo
 * In order for an odir to provide information about stream files it
 * must be opened with smb_odir_openat(). smb_odir_read_streaminfo() can
 * then be used to obtain the name and size of named stream files.
 *
 * Resuming a Search
 * -----------------
 * A directory search often consists of multiple client requests: an initial
 * find_first request followed by zero or more find_next requests and a
 * find_close request.
 * The find_first request will open and lookup the odir, read its desired
 * number of entries from the odir, then release the odir and return.
 * A find_next request will lookup the odir and read its desired number of
 * entries from the odir, then release the odir and return.
 * At the end of the search the find_close request will close the odir.
 *
 * In order to be able to resume a directory search (find_next) the odir
 * provides the capability for the caller to save one or more resume points
 * (cookies) at the end of a request, and to specify which resume point
 * (cookie) to restart from at the beginning of the next search.
 *  smb_odir_save_cookie(..., cookie)
 *  smb_odir_resume_at(smb_odir_resume_t *resume)
 * A search can be resumed at a specified resume point (cookie), the resume
 * point (cookie) stored at a specified index in the d_cookies array, or
 * a specified filename. The latter (specified filename) is not yet supported.
 *
 * See smb_search, smb_find, smb_find_unique, and smb_trans2_find for details
 */

#include <smbsrv/smb_kproto.h>
#include <smbsrv/smb_fsops.h>
#include <smbsrv/smb_share.h>
#include <sys/extdirent.h>

/* static functions */
static uint16_t smb_odir_create(smb_request_t *, smb_node_t *,
    char *, uint16_t, cred_t *);
static int smb_odir_single_fileinfo(smb_request_t *, smb_odir_t *,
    smb_fileinfo_t *);
static int smb_odir_wildcard_fileinfo(smb_request_t *, smb_odir_t *,
    smb_odirent_t *, smb_fileinfo_t *);
static int smb_odir_next_odirent(smb_odir_t *, smb_odirent_t *);
static boolean_t smb_odir_lookup_link(smb_request_t *, smb_odir_t *,
    char *, smb_node_t **);
static boolean_t smb_odir_match_name(smb_odir_t *, smb_odirent_t *);


/*
 * smb_odir_open
 *
 * Create an odir representing the directory specified in pathname.
 *
 * Returns:
 * odid - Unique identifier of newly created odir.
 *    0 - error, error details set in sr.
 */
uint16_t
smb_odir_open(smb_request_t *sr, char *path, uint16_t sattr, uint32_t flags)
{
    int     rc;
    smb_tree_t  *tree;
    smb_node_t  *dnode;
    char        pattern[MAXNAMELEN];
    uint16_t    odid;
    cred_t      *cr;

    ASSERT(sr);
    ASSERT(sr->sr_magic == SMB_REQ_MAGIC);
    ASSERT(sr->tid_tree);
    ASSERT(sr->tid_tree->t_magic == SMB_TREE_MAGIC);

    tree = sr->tid_tree;

    smb_convert_wildcards(path);

    rc = smb_pathname_reduce(sr, sr->user_cr, path,
        tree->t_snode, tree->t_snode, &dnode, pattern);
    if (rc != 0) {
        smbsr_errno(sr, rc);
        return (0);
    }

    if (!smb_node_is_dir(dnode)) {
        smbsr_error(sr, NT_STATUS_OBJECT_PATH_NOT_FOUND,
            ERRDOS, ERROR_PATH_NOT_FOUND);
        smb_node_release(dnode);
        return (0);
    }

    if (smb_fsop_access(sr, sr->user_cr, dnode, FILE_LIST_DIRECTORY) != 0) {
        smbsr_error(sr, NT_STATUS_ACCESS_DENIED,
            ERRDOS, ERROR_ACCESS_DENIED);
        smb_node_release(dnode);
        return (0);
    }

    if (flags & SMB_ODIR_OPENF_BACKUP_INTENT)
        cr = smb_user_getprivcred(tree->t_user);
    else
        cr = tree->t_user->u_cred;

    odid = smb_odir_create(sr, dnode, pattern, sattr, cr);
    smb_node_release(dnode);
    return (odid);
}

/*
 * smb_odir_openat
 *
 * Create an odir representing the extended attribute directory
 * associated with the file (or directory) represented by unode.
 *
 * Returns:
 * odid - Unique identifier of newly created odir.
 *    0 - error, error details set in sr.
 */
uint16_t
smb_odir_openat(smb_request_t *sr, smb_node_t *unode)
{
    int     rc;
    vnode_t     *xattr_dvp;
    uint16_t    odid;
    cred_t      *cr;
    char        pattern[SMB_STREAM_PREFIX_LEN + 2];

    smb_node_t  *xattr_dnode;

    ASSERT(sr);
    ASSERT(sr->sr_magic == SMB_REQ_MAGIC);
    ASSERT(unode);
    ASSERT(unode->n_magic == SMB_NODE_MAGIC);

    if (SMB_TREE_CONTAINS_NODE(sr, unode) == 0 ||
        SMB_TREE_HAS_ACCESS(sr, ACE_LIST_DIRECTORY) == 0) {
        smbsr_error(sr, NT_STATUS_ACCESS_DENIED,
            ERRDOS, ERROR_ACCESS_DENIED);
        return (0);
    }
    cr = kcred;

    /* find the xattrdir vnode */
    rc = smb_vop_lookup_xattrdir(unode->vp, &xattr_dvp, LOOKUP_XATTR, cr);
    if (rc != 0) {
        smbsr_errno(sr, rc);
        return (0);
    }

    /* lookup the xattrdir's smb_node */
    xattr_dnode = smb_node_lookup(sr, NULL, cr, xattr_dvp, XATTR_DIR,
        unode, NULL);
    VN_RELE(xattr_dvp);
    if (xattr_dnode == NULL) {
        smbsr_error(sr, NT_STATUS_NO_MEMORY,
            ERRDOS, ERROR_NOT_ENOUGH_MEMORY);
        return (0);
    }

    (void) snprintf(pattern, sizeof (pattern), "%s*", SMB_STREAM_PREFIX);
    odid = smb_odir_create(sr, xattr_dnode, pattern, SMB_SEARCH_ATTRIBUTES,
        cr);
    smb_node_release(xattr_dnode);
    return (odid);
}

/*
 * smb_odir_hold
 *
 * A hold will only be granted if the odir is open or in_use.
 */
boolean_t
smb_odir_hold(smb_odir_t *od)
{
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);

    mutex_enter(&od->d_mutex);

    switch (od->d_state) {
    case SMB_ODIR_STATE_OPEN:
        od->d_refcnt++;
        od->d_state = SMB_ODIR_STATE_IN_USE;
        break;
    case SMB_ODIR_STATE_IN_USE:
        od->d_refcnt++;
        break;
    case SMB_ODIR_STATE_CLOSING:
    case SMB_ODIR_STATE_CLOSED:
    default:
        mutex_exit(&od->d_mutex);
        return (B_FALSE);
    }

    mutex_exit(&od->d_mutex);
    return (B_TRUE);
}

/*
 * If the odir is in SMB_ODIR_STATE_CLOSING and this release results in
 * a refcnt of 0, change the state to SMB_ODIR_STATE_CLOSED and post the
 * object for deletion.  Object deletion is deferred to avoid modifying
 * a list while an iteration may be in progress.
 */
void
smb_odir_release(smb_odir_t *od)
{
    SMB_ODIR_VALID(od);

    mutex_enter(&od->d_mutex);
    ASSERT(od->d_refcnt > 0);

    switch (od->d_state) {
    case SMB_ODIR_STATE_OPEN:
        break;
    case SMB_ODIR_STATE_IN_USE:
        od->d_refcnt--;
        if (od->d_refcnt == 0)
            od->d_state = SMB_ODIR_STATE_OPEN;
        break;
    case SMB_ODIR_STATE_CLOSING:
        od->d_refcnt--;
        if (od->d_refcnt == 0) {
            od->d_state = SMB_ODIR_STATE_CLOSED;
            smb_tree_post_odir(od->d_tree, od);
        }
        break;
    case SMB_ODIR_STATE_CLOSED:
    default:
        break;
    }

    mutex_exit(&od->d_mutex);
}

/*
 * smb_odir_close
 */
void
smb_odir_close(smb_odir_t *od)
{
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);

    mutex_enter(&od->d_mutex);
    ASSERT(od->d_refcnt > 0);
    switch (od->d_state) {
    case SMB_ODIR_STATE_OPEN:
        break;
    case SMB_ODIR_STATE_IN_USE:
        od->d_state = SMB_ODIR_STATE_CLOSING;
        break;
    case SMB_ODIR_STATE_CLOSING:
    case SMB_ODIR_STATE_CLOSED:
    default:
        break;
    }
    mutex_exit(&od->d_mutex);
}

/*
 * smb_odir_read
 *
 * Find the next directory entry matching the search pattern.
 * No search attribute matching is performed.
 *
 * Returns:
 *  0 - success.
 *      - If a matching entry was found eof will be B_FALSE and
 *        odirent will be populated.
 *      - If there are no matching entries eof will be B_TRUE.
 * -1 - error, error details set in sr.
 */
int
smb_odir_read(smb_request_t *sr, smb_odir_t *od,
    smb_odirent_t *odirent, boolean_t *eof)
{
    int     rc;

    ASSERT(sr);
    ASSERT(sr->sr_magic == SMB_REQ_MAGIC);
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);
    ASSERT(odirent);

    mutex_enter(&od->d_mutex);
    ASSERT(od->d_refcnt > 0);

    switch (od->d_state) {
    case SMB_ODIR_STATE_IN_USE:
    case SMB_ODIR_STATE_CLOSING:
        break;
    case SMB_ODIR_STATE_OPEN:
    case SMB_ODIR_STATE_CLOSED:
    default:
        mutex_exit(&od->d_mutex);
        return (-1);
    }

    for (;;) {
        if ((rc = smb_odir_next_odirent(od, odirent)) != 0)
            break;
        if (smb_odir_match_name(od, odirent))
            break;
    }

    mutex_exit(&od->d_mutex);

    switch (rc) {
    case 0:
        *eof = B_FALSE;
        return (0);
    case ENOENT:
        *eof = B_TRUE;
        return (0);
    default:
        smbsr_errno(sr, rc);
        return (-1);
    }
}

/*
 * smb_odir_read_fileinfo
 *
 * Find the next directory entry matching the search pattern
 * and attributes: od->d_pattern and od->d_sattr.
 *
 * If the search pattern specifies a single filename call
 * smb_odir_single_fileinfo to get the file attributes and
 * populate the caller's smb_fileinfo_t.
 *
 * If the search pattern contains wildcards call smb_odir_next_odirent
 * to get the next directory entry then. Repeat until a matching
 * filename is found. Call smb_odir_wildcard_fileinfo to get the
 * file attributes and populate the caller's smb_fileinfo_t.
 * This is repeated until a file matching the search criteria is found.
 *
 * Returns:
 *  0 - success.
 *      - If a matching entry was found eof will be B_FALSE and
 *        fileinfo will be populated.
 *      - If there are no matching entries eof will be B_TRUE.
 * -1 - error, error details set in sr.
 */
int
smb_odir_read_fileinfo(smb_request_t *sr, smb_odir_t *od,
    smb_fileinfo_t *fileinfo, boolean_t *eof)
{
    int     rc, errnum;
    smb_odirent_t   *odirent;

    ASSERT(sr);
    ASSERT(sr->sr_magic == SMB_REQ_MAGIC);
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);
    ASSERT(fileinfo);

    mutex_enter(&od->d_mutex);
    ASSERT(od->d_refcnt > 0);

    switch (od->d_state) {
    case SMB_ODIR_STATE_IN_USE:
    case SMB_ODIR_STATE_CLOSING:
        break;
    case SMB_ODIR_STATE_OPEN:
    case SMB_ODIR_STATE_CLOSED:
    default:
        mutex_exit(&od->d_mutex);
        return (-1);
    }

    if (!(od->d_flags & SMB_ODIR_FLAG_WILDCARDS)) {
        if (od->d_eof)
            rc = ENOENT;
        else
            rc = smb_odir_single_fileinfo(sr, od, fileinfo);
        od->d_eof = B_TRUE;
    } else {
        odirent = kmem_alloc(sizeof (smb_odirent_t), KM_SLEEP);
        for (;;) {
            bzero(fileinfo, sizeof (smb_fileinfo_t));
            if ((rc = smb_odir_next_odirent(od, odirent)) != 0)
                break;

            /* skip non utf8 filename */
            if (u8_validate(odirent->od_name,
                strlen(odirent->od_name), NULL,
                U8_VALIDATE_ENTIRE, &errnum) < 0)
                continue;

            if (!smb_odir_match_name(od, odirent))
                continue;

            rc = smb_odir_wildcard_fileinfo(sr, od, odirent,
                fileinfo);
            if (rc == 0)
                break;
        }
        kmem_free(odirent, sizeof (smb_odirent_t));
    }
    mutex_exit(&od->d_mutex);

    switch (rc) {
    case 0:
        *eof = B_FALSE;
        return (0);
    case ENOENT:
        *eof = B_TRUE;
        return (0);
    default:
        smbsr_errno(sr, rc);
        return (-1);
    }
}

/*
 * smb_odir_read_streaminfo
 *
 * Find the next directory entry whose name begins with SMB_STREAM_PREFIX,
 * and thus represents an NTFS named stream.
 * No search attribute matching is performed.
 * No case conflict name mangling is required for NTFS named stream names.
 *
 * Returns:
 *  0 - success.
 *      - If a matching entry was found eof will be B_FALSE and
 *        sinfo will be populated.
 *      - If there are no matching entries eof will be B_TRUE.
 * -1 - error, error details set in sr.
 */
int
smb_odir_read_streaminfo(smb_request_t *sr, smb_odir_t *od,
    smb_streaminfo_t *sinfo, boolean_t *eof)
{
    int     rc;
    smb_odirent_t   *odirent;
    smb_node_t  *fnode;
    smb_attr_t  attr;

    ASSERT(sr);
    ASSERT(sr->sr_magic == SMB_REQ_MAGIC);
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);
    ASSERT(sinfo);

    mutex_enter(&od->d_mutex);
    ASSERT(od->d_refcnt > 0);

    switch (od->d_state) {
    case SMB_ODIR_STATE_IN_USE:
    case SMB_ODIR_STATE_CLOSING:
        break;
    case SMB_ODIR_STATE_OPEN:
    case SMB_ODIR_STATE_CLOSED:
    default:
        mutex_exit(&od->d_mutex);
        return (-1);
    }

    /* Check that odir represents an xattr directory */
    if (!(od->d_flags & SMB_ODIR_FLAG_XATTR)) {
        *eof = B_TRUE;
        mutex_exit(&od->d_mutex);
        return (0);
    }

    odirent = kmem_alloc(sizeof (smb_odirent_t), KM_SLEEP);

    for (;;) {
        bzero(sinfo, sizeof (smb_streaminfo_t));
        if ((rc = smb_odir_next_odirent(od, odirent)) != 0)
            break;

        if (strncmp(odirent->od_name, SMB_STREAM_PREFIX,
            SMB_STREAM_PREFIX_LEN)) {
            continue;
        }

        rc = smb_fsop_lookup(sr, od->d_cred, 0, od->d_tree->t_snode,
            od->d_dnode, odirent->od_name, &fnode);
        if (rc == 0) {
            rc = smb_node_getattr(sr, fnode, &attr);
            smb_node_release(fnode);
        }

        if (rc == 0) {
            (void) strlcpy(sinfo->si_name,
                odirent->od_name + SMB_STREAM_PREFIX_LEN,
                sizeof (sinfo->si_name));
            sinfo->si_size = attr.sa_vattr.va_size;
            sinfo->si_alloc_size = attr.sa_allocsz;
            break;
        }
    }
    mutex_exit(&od->d_mutex);

    kmem_free(odirent, sizeof (smb_odirent_t));

    switch (rc) {
    case 0:
        *eof = B_FALSE;
        return (0);
    case ENOENT:
        *eof = B_TRUE;
        return (0);
    default:
        smbsr_errno(sr, rc);
        return (-1);
    }
}

/*
 * smb_odir_save_cookie
 *
 * Callers can save up to SMB_MAX_SEARCH cookies in the odir
 * to be used as resume points for a 'find next' request.
 */
void
smb_odir_save_cookie(smb_odir_t *od, int idx, uint32_t cookie)
{
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);
    ASSERT(idx >= 0 && idx < SMB_MAX_SEARCH);

    mutex_enter(&od->d_mutex);
    od->d_cookies[idx] = cookie;
    mutex_exit(&od->d_mutex);
}

/*
 * smb_odir_resume_at
 *
 * If SMB_ODIR_FLAG_WILDCARDS is not set the search is for a single
 * file and should not be resumed.
 *
 * Wildcard searching can be resumed from:
 * - the cookie saved at a specified index (SMBsearch, SMBfind).
 * - a specified cookie (SMB_trans2_find)
 * - a specified filename (SMB_trans2_find) - NOT SUPPORTED.
 *   Defaults to continuing from where the last search ended.
 *
 * Continuation from where the last search ended (SMB_trans2_find)
 * is implemented by saving the last cookie at a specific index (0)
 * smb_odir_resume_at indicates a new request, so reset od->d_bufptr
 * and d_eof to force a vop_readdir.
 */
void
smb_odir_resume_at(smb_odir_t *od, smb_odir_resume_t *resume)
{
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);
    ASSERT(resume);

    mutex_enter(&od->d_mutex);

    if ((od->d_flags & SMB_ODIR_FLAG_WILDCARDS) == 0) {
        od->d_eof = B_TRUE;
        mutex_exit(&od->d_mutex);
        return;
    }

    switch (resume->or_type) {
        case SMB_ODIR_RESUME_IDX:
            ASSERT(resume->or_idx >= 0);
            ASSERT(resume->or_idx < SMB_MAX_SEARCH);

            if ((resume->or_idx < 0) ||
                (resume->or_idx >= SMB_MAX_SEARCH)) {
                resume->or_idx = 0;
            }
            od->d_offset = od->d_cookies[resume->or_idx];
            break;
        case SMB_ODIR_RESUME_COOKIE:
            od->d_offset = resume->or_cookie;
            break;
        case SMB_ODIR_RESUME_FNAME:
        default:
            od->d_offset = od->d_cookies[0];
            break;
    }

    /* Force a vop_readdir to refresh d_buf */
    od->d_bufptr = NULL;
    od->d_eof = B_FALSE;

    mutex_exit(&od->d_mutex);
}


/* *** static functions *** */

/*
 * smb_odir_create
 * Allocate and populate an odir obect and add it to the tree's list.
 */
static uint16_t
smb_odir_create(smb_request_t *sr, smb_node_t *dnode,
    char *pattern, uint16_t sattr, cred_t *cr)
{
    smb_odir_t  *od;
    smb_tree_t  *tree;
    uint16_t    odid;

    ASSERT(sr);
    ASSERT(sr->sr_magic == SMB_REQ_MAGIC);
    ASSERT(sr->tid_tree);
    ASSERT(sr->tid_tree->t_magic == SMB_TREE_MAGIC);
    ASSERT(dnode);
    ASSERT(dnode->n_magic == SMB_NODE_MAGIC);

    tree = sr->tid_tree;

    if (smb_idpool_alloc(&tree->t_odid_pool, &odid)) {
        smbsr_error(sr, NT_STATUS_TOO_MANY_OPENED_FILES,
            ERRDOS, ERROR_TOO_MANY_OPEN_FILES);
        return (0);
    }

    od = kmem_cache_alloc(tree->t_server->si_cache_odir, KM_SLEEP);
    bzero(od, sizeof (smb_odir_t));

    mutex_init(&od->d_mutex, NULL, MUTEX_DEFAULT, NULL);
    od->d_refcnt = 0;
    od->d_state = SMB_ODIR_STATE_OPEN;
    od->d_magic = SMB_ODIR_MAGIC;
    od->d_opened_by_pid = sr->smb_pid;
    od->d_session = tree->t_session;
    od->d_cred = cr;
    od->d_tree = tree;
    od->d_dnode = dnode;
    smb_node_ref(dnode);
    od->d_odid = odid;
    od->d_sattr = sattr;
    (void) strlcpy(od->d_pattern, pattern, sizeof (od->d_pattern));
    od->d_flags = 0;
    if (smb_contains_wildcards(od->d_pattern))
        od->d_flags |= SMB_ODIR_FLAG_WILDCARDS;
    if (vfs_has_feature(dnode->vp->v_vfsp, VFSFT_DIRENTFLAGS))
        od->d_flags |= SMB_ODIR_FLAG_EDIRENT;
    if (smb_tree_has_feature(tree, SMB_TREE_CASEINSENSITIVE))
        od->d_flags |= SMB_ODIR_FLAG_IGNORE_CASE;
    if (smb_tree_has_feature(tree, SMB_TREE_SHORTNAMES))
        od->d_flags |= SMB_ODIR_FLAG_SHORTNAMES;
    if (SMB_TREE_SUPPORTS_CATIA(sr))
        od->d_flags |= SMB_ODIR_FLAG_CATIA;
    if (SMB_TREE_SUPPORTS_ABE(sr))
        od->d_flags |= SMB_ODIR_FLAG_ABE;
    if (dnode->flags & NODE_XATTR_DIR)
        od->d_flags |= SMB_ODIR_FLAG_XATTR;
    od->d_eof = B_FALSE;

    smb_llist_enter(&tree->t_odir_list, RW_WRITER);
    smb_llist_insert_tail(&tree->t_odir_list, od);
    smb_llist_exit(&tree->t_odir_list);

    atomic_inc_32(&tree->t_session->s_dir_cnt);
    return (odid);
}

/*
 * Delete an odir.
 *
 * Remove the odir from the tree list before freeing resources
 * associated with the odir.
 */
void
smb_odir_delete(void *arg)
{
    smb_tree_t  *tree;
    smb_odir_t  *od = (smb_odir_t *)arg;

    SMB_ODIR_VALID(od);
    ASSERT(od->d_refcnt == 0);
    ASSERT(od->d_state == SMB_ODIR_STATE_CLOSED);

    tree = od->d_tree;
    smb_llist_enter(&tree->t_odir_list, RW_WRITER);
    smb_llist_remove(&tree->t_odir_list, od);
    smb_idpool_free(&tree->t_odid_pool, od->d_odid);
    atomic_dec_32(&tree->t_session->s_dir_cnt);
    smb_llist_exit(&tree->t_odir_list);

    mutex_enter(&od->d_mutex);
    mutex_exit(&od->d_mutex);

    od->d_magic = 0;
    smb_node_release(od->d_dnode);
    mutex_destroy(&od->d_mutex);
    kmem_cache_free(od->d_tree->t_server->si_cache_odir, od);
}

/*
 * smb_odir_next_odirent
 *
 * Find the next directory entry in d_buf. If d_bufptr is NULL (buffer
 * is empty or we've reached the end of it), read the next set of
 * entries from the file system (vop_readdir).
 *
 * File systems which support VFSFT_EDIRENT_FLAGS will return the
 * directory entries as a buffer of edirent_t structure. Others will
 * return a buffer of dirent64_t structures.  For simplicity translate
 * the data into an smb_odirent_t structure.
 * The ed_name/d_name in d_buf is NULL terminated by the file system.
 *
 * Some file systems can have directories larger than SMB_MAXDIRSIZE.
 * If the odirent offset >= SMB_MAXDIRSIZE return ENOENT and set d_eof
 * to true to stop subsequent calls to smb_vop_readdir.
 *
 * Returns:
 *      0 - success. odirent is populated with the next directory entry
 * ENOENT - no more directory entries
 *  errno - error
 */
static int
smb_odir_next_odirent(smb_odir_t *od, smb_odirent_t *odirent)
{
    int     rc;
    int     reclen;
    int     eof;
    dirent64_t  *dp;
    edirent_t   *edp;
    char        *np;
    uint32_t    abe_flag = 0;

    ASSERT(MUTEX_HELD(&od->d_mutex));

    bzero(odirent, sizeof (smb_odirent_t));

    if (od->d_bufptr != NULL) {
        if (od->d_flags & SMB_ODIR_FLAG_EDIRENT)
            reclen = od->d_edp->ed_reclen;
        else
            reclen = od->d_dp->d_reclen;

        if (reclen == 0) {
            od->d_bufptr = NULL;
        } else {
            od->d_bufptr += reclen;
            if (od->d_bufptr >= od->d_buf + od->d_bufsize)
                od->d_bufptr = NULL;
        }
    }

    if (od->d_bufptr == NULL) {
        if (od->d_eof)
            return (ENOENT);

        od->d_bufsize = sizeof (od->d_buf);

        if (od->d_flags & SMB_ODIR_FLAG_ABE)
            abe_flag = SMB_ABE;

        rc = smb_vop_readdir(od->d_dnode->vp, od->d_offset,
            od->d_buf, &od->d_bufsize, &eof, abe_flag, od->d_cred);

        if ((rc == 0) && (od->d_bufsize == 0))
            rc = ENOENT;

        if (rc != 0) {
            od->d_bufptr = NULL;
            od->d_bufsize = 0;
            return (rc);
        }

        od->d_eof = (eof != 0);
        od->d_bufptr = od->d_buf;
    }

    if (od->d_flags & SMB_ODIR_FLAG_EDIRENT)
        od->d_offset = od->d_edp->ed_off;
    else
        od->d_offset = od->d_dp->d_off;

    if (od->d_offset >= SMB_MAXDIRSIZE) {
        od->d_bufptr = NULL;
        od->d_bufsize = 0;
        od->d_eof = B_TRUE;
        return (ENOENT);
    }

    if (od->d_flags & SMB_ODIR_FLAG_EDIRENT) {
        edp = od->d_edp;
        odirent->od_ino = edp->ed_ino;
        odirent->od_eflags = edp->ed_eflags;
        np = edp->ed_name;
    } else {
        dp = od->d_dp;
        odirent->od_ino = dp->d_ino;
        odirent->od_eflags = 0;
        np =  dp->d_name;
    }

    if ((od->d_flags & SMB_ODIR_FLAG_CATIA) &&
        ((od->d_flags & SMB_ODIR_FLAG_XATTR) == 0)) {
        smb_vop_catia_v4tov5(np, odirent->od_name,
            sizeof (odirent->od_name));
    } else {
        (void) strlcpy(odirent->od_name, np,
            sizeof (odirent->od_name));
    }

    return (0);
}

/*
 * smb_odir_single_fileinfo
 *
 * Lookup the file identified by od->d_pattern.
 *
 * If the looked up file is a link, we attempt to lookup the link target
 * to use its attributes in place of those of the files's.
 * If we fail to lookup the target of the link we use the original
 * file's attributes.
 * Check if the attributes match the search attributes.
 *
 * Returns: 0 - success
 *     ENOENT - no match
 *      errno - error
 */
static int
smb_odir_single_fileinfo(smb_request_t *sr, smb_odir_t *od,
    smb_fileinfo_t *fileinfo)
{
    int     rc;
    smb_node_t  *fnode, *tgt_node;
    smb_attr_t  attr;
    ino64_t     fid;
    char        *name;
    boolean_t   case_conflict = B_FALSE;
    int     lookup_flags, flags = 0;
    vnode_t     *vp;

    ASSERT(sr);
    ASSERT(sr->sr_magic == SMB_REQ_MAGIC);
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);

    ASSERT(MUTEX_HELD(&od->d_mutex));
    bzero(fileinfo, sizeof (smb_fileinfo_t));

    rc = smb_fsop_lookup(sr, od->d_cred, 0, od->d_tree->t_snode,
        od->d_dnode, od->d_pattern, &fnode);
    if (rc != 0)
        return (rc);

    /*
     * If case sensitive, do a case insensitive smb_vop_lookup to
     * check for case conflict
     */
    if (od->d_flags & SMB_ODIR_FLAG_IGNORE_CASE) {
        lookup_flags = SMB_IGNORE_CASE;
        if (od->d_flags & SMB_ODIR_FLAG_CATIA)
            lookup_flags |= SMB_CATIA;

        rc = smb_vop_lookup(od->d_dnode->vp, fnode->od_name, &vp,
            NULL, lookup_flags, &flags, od->d_tree->t_snode->vp,
            NULL, od->d_cred);
        if (rc != 0)
            return (rc);
        VN_RELE(vp);

        if (flags & ED_CASE_CONFLICT)
            case_conflict = B_TRUE;
    }

    if ((rc = smb_node_getattr(sr, fnode, &attr)) != 0) {
        smb_node_release(fnode);
        return (rc);
    }


    /* follow link to get target node & attr */
    if (smb_node_is_symlink(fnode) &&
        smb_odir_lookup_link(sr, od, fnode->od_name, &tgt_node)) {
        smb_node_release(fnode);
        fnode = tgt_node;
        if ((rc = smb_node_getattr(sr, fnode, &attr)) != 0) {
            smb_node_release(fnode);
            return (rc);
        }
    }

    /* check search attributes */
    if (!smb_sattr_check(attr.sa_dosattr, od->d_sattr)) {
        smb_node_release(fnode);
        return (ENOENT);
    }

    name = fnode->od_name;
    if (od->d_flags & SMB_ODIR_FLAG_SHORTNAMES) {
        fid = attr.sa_vattr.va_nodeid;
        if (case_conflict || smb_needs_mangled(name)) {
            smb_mangle(name, fid, fileinfo->fi_shortname,
                SMB_SHORTNAMELEN);
        }
        if (case_conflict)
            name = fileinfo->fi_shortname;
    }

    (void) strlcpy(fileinfo->fi_name, name, sizeof (fileinfo->fi_name));

    fileinfo->fi_dosattr = attr.sa_dosattr;
    fileinfo->fi_nodeid = attr.sa_vattr.va_nodeid;
    fileinfo->fi_size = attr.sa_vattr.va_size;
    fileinfo->fi_alloc_size = attr.sa_allocsz;
    fileinfo->fi_atime = attr.sa_vattr.va_atime;
    fileinfo->fi_mtime = attr.sa_vattr.va_mtime;
    fileinfo->fi_ctime = attr.sa_vattr.va_ctime;
    if (attr.sa_crtime.tv_sec)
        fileinfo->fi_crtime = attr.sa_crtime;
    else
        fileinfo->fi_crtime = attr.sa_vattr.va_mtime;

    smb_node_release(fnode);
    return (0);
}

/*
 * smb_odir_wildcard_fileinfo
 *
 * odirent contains a directory entry, obtained from a vop_readdir.
 * If a case conflict is identified the filename is mangled and the
 * shortname is used as 'name', in place of odirent->od_name.
 *
 * If the looked up file is a link, we attempt to lookup the link target
 * to use its attributes in place of those of the files's.
 * If we fail to lookup the target of the link we use the original
 * file's attributes.
 * Check if the attributes match the search attributes.
 *
 * Although some file systems can have directories larger than
 * SMB_MAXDIRSIZE smb_odir_next_odirent ensures that no offset larger
 * than SMB_MAXDIRSIZE is returned.  It is therefore safe to use the
 * offset as the cookie (uint32_t).
 *
 * Returns: 0 - success
 *     ENOENT - no match, proceed to next entry
 *      errno - error
 */
static int
smb_odir_wildcard_fileinfo(smb_request_t *sr, smb_odir_t *od,
    smb_odirent_t *odirent, smb_fileinfo_t *fileinfo)
{
    int     rc;
    smb_node_t  *fnode, *tgt_node;
    smb_attr_t  attr;
    char        *name;
    boolean_t   case_conflict;

    ASSERT(sr);
    ASSERT(sr->sr_magic == SMB_REQ_MAGIC);
    ASSERT(od);
    ASSERT(od->d_magic == SMB_ODIR_MAGIC);

    ASSERT(MUTEX_HELD(&od->d_mutex));
    bzero(fileinfo, sizeof (smb_fileinfo_t));

    rc = smb_fsop_lookup(sr, od->d_cred, SMB_CASE_SENSITIVE,
        od->d_tree->t_snode, od->d_dnode, odirent->od_name, &fnode);
    if (rc != 0)
        return (rc);

    /* follow link to get target node & attr */
    if (smb_node_is_symlink(fnode) &&
        smb_odir_lookup_link(sr, od, odirent->od_name, &tgt_node)) {
        smb_node_release(fnode);
        fnode = tgt_node;
    }

    /* skip system files */
    if (smb_node_is_system(fnode)) {
        smb_node_release(fnode);
        return (ENOENT);
    }

    if ((rc = smb_node_getattr(sr, fnode, &attr)) != 0) {
        smb_node_release(fnode);
        return (rc);
    }

    /* check search attributes */
    if (!smb_sattr_check(attr.sa_dosattr, od->d_sattr)) {
        smb_node_release(fnode);
        return (ENOENT);
    }

    name = odirent->od_name;
    if (od->d_flags & SMB_ODIR_FLAG_SHORTNAMES) {
        case_conflict = ((od->d_flags & SMB_ODIR_FLAG_IGNORE_CASE) &&
            (odirent->od_eflags & ED_CASE_CONFLICT));
        if (case_conflict || smb_needs_mangled(name)) {
            smb_mangle(name, odirent->od_ino,
                fileinfo->fi_shortname, SMB_SHORTNAMELEN);
        }
        if (case_conflict)
            name = fileinfo->fi_shortname;
    }

    (void) strlcpy(fileinfo->fi_name, name, sizeof (fileinfo->fi_name));

    fileinfo->fi_cookie = (uint32_t)od->d_offset;
    fileinfo->fi_dosattr = attr.sa_dosattr;
    fileinfo->fi_nodeid = attr.sa_vattr.va_nodeid;
    fileinfo->fi_size = attr.sa_vattr.va_size;
    fileinfo->fi_alloc_size = attr.sa_allocsz;
    fileinfo->fi_atime = attr.sa_vattr.va_atime;
    fileinfo->fi_mtime = attr.sa_vattr.va_mtime;
    fileinfo->fi_ctime = attr.sa_vattr.va_ctime;
    if (attr.sa_crtime.tv_sec)
        fileinfo->fi_crtime = attr.sa_crtime;
    else
        fileinfo->fi_crtime = attr.sa_vattr.va_mtime;

    smb_node_release(fnode);
    return (0);
}

/*
 * smb_odir_lookup_link
 *
 * If the file is a symlink we lookup the object to which the
 * symlink refers so that we can return its attributes.
 * This can cause a problem if a symlink in a sub-directory
 * points to a parent directory (some UNIX GUI's create a symlink
 * in $HOME/.desktop that points to the user's home directory).
 * Some Windows applications (e.g. virus scanning) loop/hang
 * trying to follow this recursive path and there is little
 * we can do because the path is constructed on the client.
 * smb_dirsymlink_enable allows an end-user to disable
 * symlinks to directories. Symlinks to other object types
 * should be unaffected.
 *
 * Returns: B_TRUE  - followed link. tgt_node and tgt_attr set
 *          B_FALSE - link not followed
 */
static boolean_t
smb_odir_lookup_link(smb_request_t *sr, smb_odir_t *od,
    char *fname, smb_node_t **tgt_node)
{
    int rc;
    uint32_t flags = SMB_FOLLOW_LINKS | SMB_CASE_SENSITIVE;

    rc = smb_fsop_lookup(sr, od->d_cred, flags,
        od->d_tree->t_snode, od->d_dnode, fname, tgt_node);
    if (rc != 0) {
        *tgt_node = NULL;
        return (B_FALSE);
    }

    if (smb_node_is_dir(*tgt_node) && (!smb_dirsymlink_enable)) {
        smb_node_release(*tgt_node);
        *tgt_node = NULL;
        return (B_FALSE);
    }

    return (B_TRUE);
}

/*
 * smb_odir_match_name
 *
 * Check if the directory entry name matches the search pattern:
 * - Don't match reserved dos filenames.
 * - Check if odirent->od_name matches od->d_pattern.
 * - If shortnames are supported, generate the shortname from
 *   odirent->od_name and check if it matches od->d_pattern.
 */
boolean_t
smb_odir_match_name(smb_odir_t *od, smb_odirent_t *odirent)
{
    char    *name = odirent->od_name;
    char    shortname[SMB_SHORTNAMELEN];
    ino64_t ino = odirent->od_ino;

    if (smb_is_reserved_dos_name(name))
        return (B_FALSE);

    if (smb_match_ci(od->d_pattern, name))
        return (B_TRUE);

    if (od->d_flags & SMB_ODIR_FLAG_SHORTNAMES) {
        smb_mangle(name, ino, shortname, SMB_SHORTNAMELEN);
        if (smb_match_ci(od->d_pattern, shortname))
            return (B_TRUE);
    }

    return (B_FALSE);
}