/*      $OpenBSD: ntfs_vnops.c,v 1.51 2024/10/18 05:52:32 miod Exp $    */
/*      $NetBSD: ntfs_vnops.c,v 1.6 2003/04/10 21:57:26 jdolecek Exp $  */

/*
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * John Heidemann of the UCLA Ficus project.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      Id: ntfs_vnops.c,v 1.5 1999/05/12 09:43:06 semenu Exp
 *
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#include <sys/lock.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <sys/buf.h>
#include <sys/dirent.h>
#include <sys/specdev.h>

/*#define NTFS_DEBUG 1*/
#include <ntfs/ntfs.h>
#include <ntfs/ntfs_inode.h>
#include <ntfs/ntfs_subr.h>

#include <sys/unistd.h> /* for pathconf(2) constants */

int     ntfs_read(void *);
int     ntfs_getattr(void *);
int     ntfs_inactive(void *);
int     ntfs_print(void *);
int     ntfs_reclaim(void *);
int     ntfs_strategy(void *);
int     ntfs_access(void *v);
int     ntfs_open(void *v);
int     ntfs_close(void *);
int     ntfs_readdir(void *);
int     ntfs_lookup(void *);
int     ntfs_bmap(void *);
int     ntfs_fsync(void *);
int     ntfs_pathconf(void *);

int     ntfs_prtactive = 0;     /* 1 => print out reclaim of active vnodes */

/*
 * This is a noop, simply returning what one has been given.
 */
int
ntfs_bmap(void *v)
{
        struct vop_bmap_args *ap = v;
        DPRINTF("ntfs_bmap: vn: %p, blk: %lld\n",
            ap->a_vp, (long long)ap->a_bn);
        if (ap->a_vpp != NULL)
                *ap->a_vpp = ap->a_vp;
        if (ap->a_bnp != NULL)
                *ap->a_bnp = ap->a_bn;
        if (ap->a_runp != NULL)
                *ap->a_runp = 0;
        return (0);
}

int
ntfs_read(void *v)
{
        struct vop_read_args *ap = v;
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct uio *uio = ap->a_uio;
        struct ntfsmount *ntmp = ip->i_mp;
        u_int64_t toread;
        int error;

        DPRINTF("ntfs_read: ino: %u, off: %lld resid: %zu, segflg: %d\n",
            ip->i_number, uio->uio_offset, uio->uio_resid, uio->uio_segflg);

        DPRINTF("ntfs_read: filesize: %llu", fp->f_size);

        /* don't allow reading after end of file */
        if (uio->uio_offset > fp->f_size)
                toread = 0;
        else
                toread = MIN(uio->uio_resid, fp->f_size - uio->uio_offset);

        DPRINTF(", toread: %llu\n", toread);

        if (toread == 0)
                return (0);

        error = ntfs_readattr(ntmp, ip, fp->f_attrtype,
                fp->f_attrname, uio->uio_offset, toread, NULL, uio);
        if (error) {
                printf("ntfs_read: ntfs_readattr failed: %d\n",error);
                return (error);
        }

        return (0);
}

int
ntfs_getattr(void *v)
{
        struct vop_getattr_args *ap = v;
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct vattr *vap = ap->a_vap;

        DPRINTF("ntfs_getattr: %u, flags: %u\n", ip->i_number, ip->i_flag);

        vap->va_fsid = ip->i_dev;
        vap->va_fileid = ip->i_number;
        vap->va_mode = ip->i_mp->ntm_mode;
        vap->va_nlink = ip->i_nlink;
        vap->va_uid = ip->i_mp->ntm_uid;
        vap->va_gid = ip->i_mp->ntm_gid;
        vap->va_rdev = 0;                               /* XXX UNODEV ? */
        vap->va_size = fp->f_size;
        vap->va_bytes = fp->f_allocated;
        vap->va_atime = ntfs_nttimetounix(fp->f_times.t_access);
        vap->va_mtime = ntfs_nttimetounix(fp->f_times.t_write);
        vap->va_ctime = ntfs_nttimetounix(fp->f_times.t_create);
        vap->va_flags = ip->i_flag;
        vap->va_gen = 0;
        vap->va_blocksize = ip->i_mp->ntm_spc * ip->i_mp->ntm_bps;
        vap->va_type = vp->v_type;
        vap->va_filerev = 0;

        /*
         * Ensure that a directory link count is always 1 so that things
         * like fts_read() do not try to be smart and end up skipping over
         * directories. Additionally, ip->i_nlink will not be initialised
         * until the ntnode has been loaded for the file.
         */
        if (vp->v_type == VDIR || ip->i_nlink < 1)
                vap->va_nlink = 1;

        return (0);
}


/*
 * Last reference to an ntnode.  If necessary, write or delete it.
 */
int
ntfs_inactive(void *v)
{
        struct vop_inactive_args *ap = v;
        struct vnode *vp = ap->a_vp;
#ifdef NTFS_DEBUG
        struct ntnode *ip = VTONT(vp);
#endif

        DPRINTF("ntfs_inactive: vnode: %p, ntnode: %u\n", vp, ip->i_number);

#ifdef DIAGNOSTIC
        if (ntfs_prtactive && vp->v_usecount != 0)
                vprint("ntfs_inactive: pushing active", vp);
#endif

        VOP_UNLOCK(vp);

        /* XXX since we don't support any filesystem changes
         * right now, nothing more needs to be done
         */
        return (0);
}

/*
 * Reclaim an fnode/ntnode so that it can be used for other purposes.
 */
int
ntfs_reclaim(void *v)
{
        struct vop_reclaim_args *ap = v;
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        int error;

        DPRINTF("ntfs_reclaim: vnode: %p, ntnode: %u\n", vp, ip->i_number);

#ifdef DIAGNOSTIC
        if (ntfs_prtactive && vp->v_usecount != 0)
                vprint("ntfs_reclaim: pushing active", vp);
#endif

        if ((error = ntfs_ntget(ip)) != 0)
                return (error);
        
        /* Purge old data structures associated with the inode. */
        cache_purge(vp);

        ntfs_frele(fp);
        ntfs_ntput(ip);

        vp->v_data = NULL;

        return (0);
}

int
ntfs_print(void *v)
{
#if defined(DEBUG) || defined(DIAGNOSTIC) || defined(VFSLCKDEBUG)
        struct vop_print_args *ap = v;
        struct ntnode *ip = VTONT(ap->a_vp);

        printf("tag VT_NTFS, ino %u, flag %#x, usecount %d, nlink %ld\n",
            ip->i_number, ip->i_flag, ip->i_usecount, ip->i_nlink);
#endif

        return (0);
}

/*
 * Calculate the logical to physical mapping if not done already,
 * then call the device strategy routine.
 */
int
ntfs_strategy(void *v)
{
        struct vop_strategy_args *ap = v;
        struct buf *bp = ap->a_bp;
        struct vnode *vp = bp->b_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct ntfsmount *ntmp = ip->i_mp;
        int error, s;

        DPRINTF("ntfs_strategy: blkno: %lld, lblkno: %lld\n",
            (long long)bp->b_blkno, (long long)bp->b_lblkno);

        DPRINTF("strategy: bcount: %ld flags: 0x%lx\n",
            bp->b_bcount, bp->b_flags);

        if (bp->b_flags & B_READ) {
                u_int32_t toread;

                if (ntfs_cntob(bp->b_blkno) >= fp->f_size) {
                        clrbuf(bp);
                        error = 0;
                } else {
                        toread = MIN(bp->b_bcount,
                                 fp->f_size - ntfs_cntob(bp->b_blkno));
                        DPRINTF("ntfs_strategy: toread: %u, fsize: %llu\n",
                            toread, fp->f_size);

                        error = ntfs_readattr(ntmp, ip, fp->f_attrtype,
                                fp->f_attrname, ntfs_cntob(bp->b_blkno),
                                toread, bp->b_data, NULL);

                        if (error) {
                                printf("ntfs_strategy: ntfs_readattr failed\n");
                                bp->b_error = error;
                                bp->b_flags |= B_ERROR;
                        }

                        bzero(bp->b_data + toread, bp->b_bcount - toread);
                }
        } else {
                bp->b_error = error = EROFS;
                bp->b_flags |= B_ERROR;
        }
        s = splbio();
        biodone(bp);
        splx(s);
        return (error);
}

int
ntfs_access(void *v)
{
        struct vop_access_args *ap = v;
        struct vnode *vp = ap->a_vp;
        struct ntnode *ip = VTONT(vp);
        struct ucred *cred = ap->a_cred;
        mode_t mask, mode = ap->a_mode;
        gid_t *gp;
        int i;

        DPRINTF("ntfs_access: %u\n", ip->i_number);

        /*
         * Disallow write attempts unless the file is a socket, fifo, or
         * a block or character device resident on the file system.
         */
        if (mode & VWRITE) {
                switch ((int)vp->v_type) {
                case VDIR:
                case VLNK:
                case VREG:
                        return (EROFS);
                }
        }

        /* Otherwise, user id 0 always gets access. */
        if (cred->cr_uid == 0)
                return (0);

        mask = 0;

        /* Otherwise, check the owner. */
        if (cred->cr_uid == ip->i_mp->ntm_uid) {
                if (mode & VEXEC)
                        mask |= S_IXUSR;
                if (mode & VREAD)
                        mask |= S_IRUSR;
                if (mode & VWRITE)
                        mask |= S_IWUSR;
                return ((ip->i_mp->ntm_mode & mask) == mask ? 0 : EACCES);
        }

        /* Otherwise, check the groups. */
        for (i = 0, gp = cred->cr_groups; i < cred->cr_ngroups; i++, gp++)
                if (ip->i_mp->ntm_gid == *gp) {
                        if (mode & VEXEC)
                                mask |= S_IXGRP;
                        if (mode & VREAD)
                                mask |= S_IRGRP;
                        if (mode & VWRITE)
                                mask |= S_IWGRP;
                        return ((ip->i_mp->ntm_mode&mask) == mask ? 0 : EACCES);
                }

        /* Otherwise, check everyone else. */
        if (mode & VEXEC)
                mask |= S_IXOTH;
        if (mode & VREAD)
                mask |= S_IROTH;
        if (mode & VWRITE)
                mask |= S_IWOTH;
        return ((ip->i_mp->ntm_mode & mask) == mask ? 0 : EACCES);
}

/*
 * Open called.
 *
 * Nothing to do.
 */
int
ntfs_open(void *v)
{
#if NTFS_DEBUG
        struct vop_open_args *ap = v;
        struct vnode *vp = ap->a_vp;
        struct ntnode *ip = VTONT(vp);

        printf("ntfs_open: %d\n",ip->i_number);
#endif

        /*
         * Files marked append-only must be opened for appending.
         */

        return (0);
}

/*
 * Close called.
 *
 * Update the times on the inode.
 */
int
ntfs_close(void *v)
{
#if NTFS_DEBUG
        struct vop_close_args *ap = v;
        struct vnode *vp = ap->a_vp;
        struct ntnode *ip = VTONT(vp);

        printf("ntfs_close: %d\n",ip->i_number);
#endif

        return (0);
}

int
ntfs_readdir(void *v)
{
        struct vop_readdir_args *ap = v;
        struct vnode *vp = ap->a_vp;
        struct fnode *fp = VTOF(vp);
        struct ntnode *ip = FTONT(fp);
        struct uio *uio = ap->a_uio;
        struct ntfsmount *ntmp = ip->i_mp;
        int i, error = 0;
        u_int32_t faked = 0, num;
        struct dirent cde;
        off_t off;

        DPRINTF("ntfs_readdir %u off: %lld resid: %zu\n", ip->i_number,
            uio->uio_offset, uio->uio_resid);

        off = uio->uio_offset;
        memset(&cde, 0, sizeof(cde));

        /* Simulate . in every dir except ROOT */
        if (ip->i_number != NTFS_ROOTINO && uio->uio_offset == 0) {
                cde.d_fileno = ip->i_number;
                cde.d_reclen = sizeof(struct dirent);
                cde.d_type = DT_DIR;
                cde.d_namlen = 1;
                cde.d_off = sizeof(struct dirent);
                cde.d_name[0] = '.';
                cde.d_name[1] = '\0';
                error = uiomove(&cde, sizeof(struct dirent), uio);
                if (error)
                        goto out;
        }

        /* Simulate .. in every dir including ROOT */
        if (uio->uio_offset < 2 * sizeof(struct dirent)) {
                cde.d_fileno = NTFS_ROOTINO;    /* XXX */
                cde.d_reclen = sizeof(struct dirent);
                cde.d_type = DT_DIR;
                cde.d_namlen = 2;
                cde.d_off = 2 * sizeof(struct dirent);
                cde.d_name[0] = '.';
                cde.d_name[1] = '.';
                cde.d_name[2] = '\0';
                error = uiomove(&cde, sizeof(struct dirent), uio);
                if (error)
                        goto out;
        }

        faked = (ip->i_number == NTFS_ROOTINO) ? 1 : 2;
        num = uio->uio_offset / sizeof(struct dirent) - faked;

        while (uio->uio_resid >= sizeof(struct dirent)) {
                struct attr_indexentry *iep;
                char *fname;
                size_t remains;
                int sz;

                error = ntfs_ntreaddir(ntmp, fp, num, &iep, uio->uio_procp);
                if (error)
                        goto out;

                if (NULL == iep)
                        break;

                for(; !(iep->ie_flag & NTFS_IEFLAG_LAST) && (uio->uio_resid >= sizeof(struct dirent));
                        iep = NTFS_NEXTREC(iep, struct attr_indexentry *))
                {
                        if(!ntfs_isnamepermitted(ntmp,iep))
                                continue;

                        remains = sizeof(cde.d_name) - 1;
                        fname = cde.d_name;
                        for(i=0; i<iep->ie_fnamelen; i++) {
                                sz = (*ntmp->ntm_wput)(fname, remains,
                                                iep->ie_fname[i]);
                                fname += sz;
                                remains -= sz;
                        }
                        *fname = '\0';
                        DPRINTF("ntfs_readdir: elem: %u, fname:[%s] type: %u, "
                            "flag: %u, ",
                            num, cde.d_name, iep->ie_fnametype, iep->ie_flag);
                        cde.d_namlen = fname - (char *) cde.d_name;
                        if (memchr(cde.d_name, '/', cde.d_namlen) != NULL) {
                                error = EINVAL;
                                goto out;
                        }
                        cde.d_fileno = iep->ie_number;
                        cde.d_type = (iep->ie_fflag & NTFS_FFLAG_DIR) ? DT_DIR : DT_REG;
                        cde.d_reclen = sizeof(struct dirent);
                        cde.d_off = uio->uio_offset + sizeof(struct dirent);
                        DPRINTF("%s\n", cde.d_type == DT_DIR ? "dir" : "reg");

                        error = uiomove(&cde, sizeof(struct dirent), uio);
                        if (error)
                                goto out;
                        num++;
                }
        }

        DPRINTF("ntfs_readdir: %u entries (%lld bytes) read\n",
            num, uio->uio_offset - off);
        DPRINTF("ntfs_readdir: off: %lld resid: %zu\n",
            uio->uio_offset, uio->uio_resid);

/*
        if (ap->a_eofflag)
            *ap->a_eofflag = VTONT(ap->a_vp)->i_size <= uio->uio_offset;
*/
out:
        if (fp->f_dirblbuf != NULL) {
                free(fp->f_dirblbuf, M_NTFSDIR, 0);
                fp->f_dirblbuf = NULL;
        }
        return (error);
}

int
ntfs_lookup(void *v)
{
        struct vop_lookup_args *ap = v;
        struct vnode *dvp = ap->a_dvp;
        struct ntnode *dip = VTONT(dvp);
        struct ntfsmount *ntmp = dip->i_mp;
        struct componentname *cnp = ap->a_cnp;
        struct ucred *cred = cnp->cn_cred;
        int error;
        int lockparent = cnp->cn_flags & LOCKPARENT;
#if NTFS_DEBUG
        int wantparent = cnp->cn_flags & (LOCKPARENT|WANTPARENT);
#endif
        DPRINTF("ntfs_lookup: \"%.*s\" (%ld bytes) in %u, lp: %d, wp: %d \n",
            (unsigned int)cnp->cn_namelen, cnp->cn_nameptr, cnp->cn_namelen,
            dip->i_number, lockparent, wantparent);

        error = VOP_ACCESS(dvp, VEXEC, cred, cnp->cn_proc);
        if(error)
                return (error);

        if ((cnp->cn_flags & ISLASTCN) &&
            (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
                return (EROFS);

        /*
         * We now have a segment name to search for, and a directory
         * to search.
         *
         * Before tediously performing a linear scan of the directory,
         * check the name cache to see if the directory/name pair
         * we are looking for is known already.
         */
        if ((error = cache_lookup(ap->a_dvp, ap->a_vpp, cnp)) >= 0)
                return (error);

        if(cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
                DPRINTF("ntfs_lookup: faking . directory in %u\n",
                    dip->i_number);

                vref(dvp);
                *ap->a_vpp = dvp;
                error = 0;
        } else if (cnp->cn_flags & ISDOTDOT) {
                struct ntvattr *vap;

                DPRINTF("ntfs_lookup: faking .. directory in %u\n",
                    dip->i_number);

                VOP_UNLOCK(dvp);
                cnp->cn_flags |= PDIRUNLOCK;

                error = ntfs_ntvattrget(ntmp, dip, NTFS_A_NAME, NULL, 0, &vap);
                if(error)
                        return (error);

                DPRINTF("ntfs_lookup: parentdir: %u\n",
                    vap->va_a_name->n_pnumber);
                error = VFS_VGET(ntmp->ntm_mountp,
                                 vap->va_a_name->n_pnumber,ap->a_vpp); 
                ntfs_ntvattrrele(vap);
                if (error) {
                        if (vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY) == 0)
                                cnp->cn_flags &= ~PDIRUNLOCK;
                        return (error);
                }

                if (lockparent && (cnp->cn_flags & ISLASTCN)) {
                        error = vn_lock(dvp, LK_EXCLUSIVE);
                        if (error) {
                                vput( *(ap->a_vpp) );
                                return (error);
                        }
                        cnp->cn_flags &= ~PDIRUNLOCK;
                }
        } else {
                error = ntfs_ntlookupfile(ntmp, dvp, cnp, ap->a_vpp);
                if (error) {
                        DPRINTF("ntfs_ntlookupfile: returned %d\n", error);
                        return (error);
                }

                DPRINTF("ntfs_lookup: found ino: %u\n",
                    VTONT(*ap->a_vpp)->i_number);

                if(!lockparent || (cnp->cn_flags & ISLASTCN) == 0) {
                        VOP_UNLOCK(dvp);
                        cnp->cn_flags |= PDIRUNLOCK;
                }
        }

        if (cnp->cn_flags & MAKEENTRY)
                cache_enter(dvp, *ap->a_vpp, cnp);

        return (error);
}

/*
 * Flush the blocks of a file to disk.
 *
 * This function is worthless for vnodes that represent directories. Maybe we
 * could just do a sync if they try an fsync on a directory file.
 */
int
ntfs_fsync(void *v)
{
        return (0);
}

/*
 * Return POSIX pathconf information applicable to NTFS filesystem
 */
int
ntfs_pathconf(void *v)
{
        struct vop_pathconf_args *ap = v;
        int error = 0;

        switch (ap->a_name) {
        case _PC_LINK_MAX:
                *ap->a_retval = 1;
                break;
        case _PC_NAME_MAX:
                *ap->a_retval = NTFS_MAXFILENAME;
                break;
        case _PC_CHOWN_RESTRICTED:
                *ap->a_retval = 1;
                break;
        case _PC_NO_TRUNC:
                *ap->a_retval = 0;
                break;
        default:
                error = EINVAL;
                break;
        }

        return (error);
}

/*
 * Global vfs data structures
 */
const struct vops ntfs_vops = {
        .vop_getattr    = ntfs_getattr,
        .vop_inactive   = ntfs_inactive,
        .vop_reclaim    = ntfs_reclaim,
        .vop_print      = ntfs_print,
        .vop_pathconf   = ntfs_pathconf,
        .vop_lock       = nullop,
        .vop_unlock     = nullop,
        .vop_islocked   = nullop,
        .vop_lookup     = ntfs_lookup,
        .vop_access     = ntfs_access,
        .vop_close      = ntfs_close,
        .vop_open       = ntfs_open,
        .vop_readdir    = ntfs_readdir,
        .vop_fsync      = ntfs_fsync,
        .vop_bmap       = ntfs_bmap,
        .vop_strategy   = ntfs_strategy,
        .vop_bwrite     = vop_generic_bwrite,
        .vop_read       = ntfs_read,

        .vop_abortop    = NULL,
        .vop_advlock    = NULL,
        .vop_create     = NULL,
        .vop_ioctl      = NULL,
        .vop_link       = NULL,
        .vop_mknod      = NULL,
        .vop_readlink   = NULL,
        .vop_remove     = eopnotsupp,
        .vop_rename     = NULL,
        .vop_revoke     = NULL,
        .vop_mkdir      = NULL,
        .vop_rmdir      = NULL,
        .vop_setattr    = NULL,
        .vop_symlink    = NULL,
        .vop_write      = NULL,
        .vop_kqfilter   = NULL
};