source3/modules/vfs_crossrename.c

   1 /*
   2  * Copyright (c) Björn Jacke 2010
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "includes.h"
  19 #include "smbd/smbd.h"
  20 #include "system/filesys.h"
  21 #include "transfer_file.h"
  22 #include "smbprofile.h"
  23
  24 #define MODULE "crossrename"
  25 static off_t module_sizelimit;
  26
  27 static int crossrename_connect(
  28                 struct vfs_handle_struct *  handle,
  29                 const char *                service,
  30                 const char *                user)
  31 {
  32         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
  33
  34         if (ret < 0) {
  35                 return ret;
  36         }
  37
  38         module_sizelimit = (off_t) lp_parm_int(SNUM(handle->conn),
  39                                         MODULE, "sizelimit", 20);
  40         /* convert from MiB to byte: */
  41         module_sizelimit *= 1048576;
  42
  43         return 0;
  44 }
  45
  46 /*********************************************************
  47  For rename across filesystems initial Patch from Warren Birnbaum
  48  <warrenb@hpcvscdp.cv.hp.com>
  49 **********************************************************/
  50
  51 static NTSTATUS copy_reg(vfs_handle_struct *handle,
  52                          struct files_struct *srcfsp,
  53                          const struct smb_filename *source,
  54                          struct files_struct *dstfsp,
  55                          const struct smb_filename *dest)
  56 {
  57         NTSTATUS status;
  58         struct smb_filename *full_fname_src = NULL;
  59         struct smb_filename *full_fname_dst = NULL;
  60         int ret;
  61
  62         if (!VALID_STAT(source->st)) {
  63                 status = NT_STATUS_OBJECT_PATH_NOT_FOUND;
  64                 goto out;
  65         }
  66         if (!S_ISREG(source->st.st_ex_mode)) {
  67                 status = NT_STATUS_OBJECT_PATH_NOT_FOUND;
  68                 goto out;
  69         }
  70
  71         if (source->st.st_ex_size > module_sizelimit) {
  72                 DBG_INFO("%s: size of %s larger than sizelimit (%lld > %lld), "
  73                          "rename prohibited\n",
  74                         MODULE,
  75                         source->base_name,
  76                         (long long)source->st.st_ex_size,
  77                         (long long)module_sizelimit);
  78                 status = NT_STATUS_INVALID_PARAMETER;
  79                 goto out;
  80         }
  81
  82         full_fname_src = full_path_from_dirfsp_atname(talloc_tos(),
  83                                                       srcfsp,
  84                                                       source);
  85         if (full_fname_src == NULL) {
  86                 status = NT_STATUS_NO_MEMORY;
  87                 goto out;
  88         }
  89         full_fname_dst = full_path_from_dirfsp_atname(talloc_tos(),
  90                                                       dstfsp,
  91                                                       dest);
  92         if (full_fname_dst == NULL) {
  93                 status = NT_STATUS_NO_MEMORY;
  94                 goto out;
  95         }
  96
  97         ret = SMB_VFS_NEXT_UNLINKAT(handle,
  98                                     dstfsp,
  99                                     dest,
 100                                     0);
 101         if (ret == -1) {
 102                 status = map_nt_error_from_unix(errno);
 103                 goto out;
 104         }
 105
 106         /*
 107          * copy_internals() takes attribute values from the NTrename call.
 108          *
 109          * From MS-CIFS:
 110          *
 111          * "If the attribute is 0x0000, then only normal files are renamed.
 112          * If the system file or hidden attributes are specified, then the
 113          * rename is inclusive of both special types."
 114          */
 115         status = copy_internals(talloc_tos(),
 116                                 handle->conn,
 117                                 NULL,
 118                                 srcfsp, /* src_dirfsp */
 119                                 full_fname_src,
 120                                 dstfsp, /* dst_dirfsp */
 121                                 full_fname_dst,
 122                                 FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_SYSTEM);
 123         if (!NT_STATUS_IS_OK(status)) {
 124                 goto out;
 125         }
 126
 127         ret = SMB_VFS_NEXT_UNLINKAT(handle,
 128                                     srcfsp,
 129                                     source,
 130                                     0);
 131         if (ret == -1) {
 132                 status = map_nt_error_from_unix(errno);
 133                 goto out;
 134         }
 135
 136   out:
 137
 138         TALLOC_FREE(full_fname_src);
 139         TALLOC_FREE(full_fname_dst);
 140         return status;
 141 }
 142
 143 static int crossrename_renameat(vfs_handle_struct *handle,
 144                         files_struct *srcfsp,
 145                         const struct smb_filename *smb_fname_src,
 146                         files_struct *dstfsp,
 147                         const struct smb_filename *smb_fname_dst)
 148 {
 149         int result = -1;
 150
 151         START_PROFILE(syscall_renameat);
 152
 153         if (smb_fname_src->stream_name || smb_fname_dst->stream_name) {
 154                 errno = ENOENT;
 155                 goto out;
 156         }
 157
 158         result = SMB_VFS_NEXT_RENAMEAT(handle,
 159                                        srcfsp,
 160                                        smb_fname_src,
 161                                        dstfsp,
 162                                        smb_fname_dst);
 163
 164         if ((result == -1) && (errno == EXDEV)) {
 165                 /* Rename across filesystems needed. */
 166                 NTSTATUS status = copy_reg(handle,
 167                                            srcfsp,
 168                                            smb_fname_src,
 169                                            dstfsp,
 170                                            smb_fname_dst);
 171                 if (!NT_STATUS_IS_OK(status)) {
 172                         errno = map_errno_from_nt_status(status);
 173                         result = -1;
 174                 }
 175         }
 176
 177  out:
 178         END_PROFILE(syscall_renameat);
 179         return result;
 180 }
 181
 182
 183 static struct vfs_fn_pointers vfs_crossrename_fns = {
 184         .connect_fn = crossrename_connect,
 185         .renameat_fn = crossrename_renameat
 186 };
 187
 188 static_decl_vfs;
 189 NTSTATUS vfs_crossrename_init(TALLOC_CTX *ctx)
 190 {
 191         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, MODULE,
 192                                 &vfs_crossrename_fns);
 193 }
 194