source: trunk/server/source3/modules/vfs_crossrename.c@ 751

/*
 * Copyright (c) Björn Jacke 2010
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include "includes.h"
#include "smbd/smbd.h"
#include "system/filesys.h"
#include "transfer_file.h"
#include "smbprofile.h"

#define MODULE "crossrename"
static SMB_OFF_T module_sizelimit;

static int crossrename_connect(
                struct vfs_handle_struct *  handle,
                const char *                service,
                const char *                user)
{
        int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);

        if (ret < 0) {
                return ret;
        }

        module_sizelimit = (SMB_OFF_T) lp_parm_int(SNUM(handle->conn),
                                        MODULE, "sizelimit", 20);
        /* convert from MiB to byte: */
        module_sizelimit *= 1048576;

        return 0;
}

/*********************************************************
 For rename across filesystems initial Patch from Warren Birnbaum
 <[email protected]>
**********************************************************/

static int copy_reg(const char *source, const char *dest)
{
        SMB_STRUCT_STAT source_stats;
        int saved_errno;
        int ifd = -1;
        int ofd = -1;

        if (sys_lstat(source, &source_stats, false) == -1)
                return -1;

        if (!S_ISREG (source_stats.st_ex_mode))
                return -1;

        if (source_stats.st_ex_size > module_sizelimit) {
                DEBUG(5,
                        ("%s: size of %s larger than sizelimit (%lld > %lld), rename prohititted\n",
                        MODULE, source,
                        (long long)source_stats.st_ex_size,
                        (long long)module_sizelimit));
                return -1;
        }

        if((ifd = sys_open (source, O_RDONLY, 0)) < 0)
                return -1;

        if (unlink (dest) && errno != ENOENT)
                return -1;

#ifdef O_NOFOLLOW
        if((ofd = sys_open (dest, O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW, 0600)) < 0 )
#else
        if((ofd = sys_open (dest, O_WRONLY | O_CREAT | O_TRUNC , 0600)) < 0 )
#endif
                goto err;

        if (transfer_file(ifd, ofd, source_stats.st_ex_size) == -1)
                goto err;

        /*
         * Try to preserve ownership.  For non-root it might fail, but that's ok.
         * But root probably wants to know, e.g. if NFS disallows it.
         */

#ifdef HAVE_FCHOWN
        if ((fchown(ofd, source_stats.st_ex_uid, source_stats.st_ex_gid) == -1) && (errno != EPERM))
#else
        if ((chown(dest, source_stats.st_ex_uid, source_stats.st_ex_gid) == -1) && (errno != EPERM))
#endif
                goto err;

        /*
         * fchown turns off set[ug]id bits for non-root,
         * so do the chmod last.
         */

#if defined(HAVE_FCHMOD)
        if (fchmod (ofd, source_stats.st_ex_mode & 07777))
#else
        if (chmod (dest, source_stats.st_ex_mode & 07777))
#endif
                goto err;

        if (close (ifd) == -1)
                goto err;

        if (close (ofd) == -1)
                return -1;

        /* Try to copy the old file's modtime and access time.  */
#if defined(HAVE_UTIMENSAT)
        {