source3/smbd/smb2_posix.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    SMB2 POSIX code.
   4    Copyright (C) Jeremy Allison                 2022
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "smbd/smbd.h"
  22 #include "passdb/lookup_sid.h"
  23 #include "librpc/gen_ndr/ndr_security.h"
  24 #include "librpc/gen_ndr/smb3posix.h"
  25 #include "libcli/security/security.h"
  26 #include "source3/modules/util_reparse.h"
  27 #include "libcli/smb/reparse.h"
  28
  29 static NTSTATUS reparse_buffer_parse_posix_type(uint32_t reparse_tag,
  30                                                 uint8_t *data,
  31                                                 uint32_t len,
  32                                                 mode_t *type)
  33 {
  34         struct reparse_data_buffer *reparse = NULL;
  35         NTSTATUS status;
  36
  37         if (reparse_tag == IO_REPARSE_TAG_SYMLINK) {
  38                 *type = S_IFLNK;
  39                 return NT_STATUS_OK;
  40         }
  41         if (reparse_tag != IO_REPARSE_TAG_NFS) {
  42                 /*
  43                  * Clients can create reparse points with arbitrary tags, return
  44                  * anything that is not a NFS one (or symlink) as S_IFREG.
  45                  */
  46                 DBG_INFO("Unhandled NFS reparse tag: 0x%" PRIx32 "\n",
  47                          reparse->tag);
  48                 *type = S_IFREG;
  49                 return NT_STATUS_OK;
  50         }
  51
  52         reparse = talloc_zero(talloc_tos(), struct reparse_data_buffer);
  53         if (reparse == NULL) {
  54                 DBG_ERR("talloc_zero() failed\n");
  55                 return NT_STATUS_NO_MEMORY;
  56         }
  57
  58         status = reparse_data_buffer_parse(reparse, reparse, data, len);
  59         if (!NT_STATUS_IS_OK(status)) {
  60                 TALLOC_FREE(reparse);
  61                 return status;
  62         }
  63
  64         switch (reparse->parsed.nfs.type) {
  65         case NFS_SPECFILE_CHR:
  66                 *type = S_IFCHR;
  67                 break;
  68         case NFS_SPECFILE_BLK:
  69                 *type = S_IFBLK;
  70                 break;
  71         case NFS_SPECFILE_FIFO:
  72                 *type = S_IFIFO;
  73                 break;
  74         case NFS_SPECFILE_SOCK:
  75                 *type = S_IFSOCK;
  76                 break;
  77         default:
  78                 DBG_ERR("Unhandled NFS reparse type: 0x%" PRIx64 "\n",
  79                         reparse->parsed.nfs.type);
  80                 TALLOC_FREE(reparse);
  81                 return NT_STATUS_REPARSE_POINT_NOT_RESOLVED;
  82         }
  83
  84         TALLOC_FREE(reparse);
  85         return status;
  86 }
  87
  88 NTSTATUS smb3_file_posix_information_init(
  89         connection_struct *conn,
  90         const struct smb_filename *smb_fname,
  91         uint32_t dos_attributes,
  92         struct smb3_file_posix_information *dst)
  93 {
  94         const struct stat_ex *st = &smb_fname->st;
  95         mode_t mode = st->st_ex_mode;
  96         uint32_t reparse_tag = 0;
  97         NTSTATUS status;
  98
  99         switch (mode & S_IFMT) {
 100         case S_IFREG:
 101         case S_IFDIR:
 102                 break;
 103         default:
 104                 /*
 105                  * All non-directory or regular files are reported
 106                  * as reparse points. Client may or may not be able
 107                  * to access these. This should already be set by
 108                  * fdos_mode(), assert this.
 109                  */
 110                 SMB_ASSERT(dos_attributes & FILE_ATTRIBUTE_REPARSE_POINT);
 111                 break;
 112         }
 113
 114         if (dos_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
 115                 uint8_t *reparse_data = NULL;
 116                 uint32_t reparse_len;
 117                 mode_t type = S_IFREG;
 118
 119                 status = fsctl_get_reparse_point(smb_fname->fsp,
 120                                                  talloc_tos(),
 121                                                  &reparse_tag,
 122                                                  &reparse_data,
 123                                                  UINT32_MAX,
 124                                                  &reparse_len);
 125                 if (!NT_STATUS_IS_OK(status)) {
 126                         DBG_DEBUG("Could not get reparse point for %s: %s\n",
 127                                   smb_fname_str_dbg(smb_fname),
 128                                   nt_errstr(status));
 129                         return status;
 130                 }
 131
 132                 status = reparse_buffer_parse_posix_type(reparse_tag,
 133                                                          reparse_data,
 134                                                          reparse_len,
 135                                                          &type);
 136                 TALLOC_FREE(reparse_data);
 137                 if (!NT_STATUS_IS_OK(status)) {
 138                         DBG_DEBUG("Could not parse reparse data for %s: %s\n",
 139                                   smb_fname_str_dbg(smb_fname),
 140                                   nt_errstr(status));
 141                         return status;
 142                 }
 143
 144                 /*
 145                  * Remove the type info we got via stat() and use what
 146                  * we got from the reparse point.
 147                  */
 148                 mode &= ~S_IFMT;
 149                 mode |= type;
 150         }
 151
 152         *dst = (struct smb3_file_posix_information) {
 153                 .end_of_file = get_file_size_stat(st),
 154                 .allocation_size = SMB_VFS_GET_ALLOC_SIZE(conn,NULL,st),
 155                 .inode = SMB_VFS_FS_FILE_ID(conn, st),
 156                 .device = st->st_ex_dev,
 157                 .creation_time = unix_timespec_to_nt_time(st->st_ex_btime),
 158                 .last_access_time = unix_timespec_to_nt_time(st->st_ex_atime),
 159                 .last_write_time = unix_timespec_to_nt_time(st->st_ex_mtime),
 160                 .change_time = unix_timespec_to_nt_time(st->st_ex_ctime),
 161                 .file_attributes = dos_attributes,
 162                 .cc.nlinks = st->st_ex_nlink,
 163                 .cc.reparse_tag = reparse_tag,
 164                 .cc.posix_mode = unix_mode_to_wire(mode),
 165                 .cc.owner = global_sid_NULL,
 166                 .cc.group = global_sid_NULL,
 167         };
 168
 169         if (st->st_ex_uid != (uid_t)-1) {
 170                 uid_to_sid(&dst->cc.owner, st->st_ex_uid);
 171         }
 172         if (st->st_ex_gid != (uid_t)-1) {
 173                 gid_to_sid(&dst->cc.group, st->st_ex_gid);
 174         }
 175         return NT_STATUS_OK;
 176 }