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 "libcli/security/security.h"
  25
  26 /*
  27  * SMB2 POSIX create context return details.
  28  */
  29 ssize_t smb2_posix_cc_info(
  30         connection_struct *conn,
  31         uint32_t reparse_tag,
  32         const SMB_STRUCT_STAT *psbuf,
  33         const struct dom_sid *owner,
  34         const struct dom_sid *group,
  35         uint8_t *buf,
  36         size_t buflen)
  37 {
  38         size_t owner_sid_size = ndr_size_dom_sid(owner, 0);
  39         size_t group_sid_size = ndr_size_dom_sid(group, 0);
  40         size_t b_size = 12;
  41
  42         owner_sid_size = ndr_size_dom_sid(owner, 0);
  43         if (b_size + owner_sid_size < b_size) {
  44                 return -1;
  45         }
  46         b_size += owner_sid_size;
  47
  48         group_sid_size = ndr_size_dom_sid(group, 0);
  49         if (b_size + group_sid_size < b_size) {
  50                 return -1;
  51         }
  52         b_size += group_sid_size;
  53
  54         if (buflen < b_size) {
  55                 return b_size;
  56         }
  57
  58         /* number of hard links */
  59         PUSH_LE_U32(buf, 0, psbuf->st_ex_nlink);
  60
  61         /* Reparse tag if FILE_FLAG_REPARSE is set, else zero. */
  62         PUSH_LE_U32(buf, 4, reparse_tag);
  63
  64         /*
  65          * Remove type info from mode, leaving only the
  66          * permissions and setuid/gid bits.
  67          */
  68         PUSH_LE_U32(buf,
  69                     8,
  70                     unix_perms_to_wire(psbuf->st_ex_mode & ~S_IFMT));
  71
  72         buf += 12;
  73         buflen -= 12;
  74
  75         /* Now add in the owner and group sids. */
  76         sid_linearize(buf, buflen, owner);
  77         buf += owner_sid_size;
  78         buflen -= owner_sid_size;
  79
  80         sid_linearize(buf, buflen, group);
  81
  82         return b_size;
  83 }
  84
  85 /*
  86  * SMB2 POSIX info level.
  87  */
  88 ssize_t store_smb2_posix_info(
  89         connection_struct *conn,
  90         const SMB_STRUCT_STAT *psbuf,
  91         uint32_t reparse_tag,
  92         uint32_t dos_attributes,
  93         uint8_t *buf,
  94         size_t buflen)
  95 {
  96         uint64_t file_id = SMB_VFS_FS_FILE_ID(conn, psbuf);
  97         struct dom_sid owner = global_sid_NULL;
  98         struct dom_sid group = global_sid_NULL;
  99         ssize_t cc_len;
 100
 101         if (psbuf->st_ex_uid != (uid_t)-1) {
 102                 uid_to_sid(&owner, psbuf->st_ex_uid);
 103         }
 104         if (psbuf->st_ex_gid != (gid_t)-1) {
 105                 gid_to_sid(&group, psbuf->st_ex_gid);
 106         }
 107
 108         cc_len = smb2_posix_cc_info(
 109                 conn, reparse_tag, psbuf, &owner, &group, NULL, 0);
 110
 111         if (cc_len == -1) {
 112                 return -1;
 113         }
 114
 115         if (cc_len + 68 < 68) {
 116                 return -1;
 117         }
 118
 119         if (buflen < cc_len + 68) {
 120                 return cc_len + 68;
 121         }
 122
 123         /* Timestamps. */
 124
 125         /* Birth (creation) time. */
 126         put_long_date_timespec(TIMESTAMP_SET_NT_OR_BETTER,
 127                                (char *)buf+0,
 128                                psbuf->st_ex_btime);
 129         /* Access time. */
 130         put_long_date_timespec(TIMESTAMP_SET_NT_OR_BETTER,
 131                                (char *)buf+8,
 132                                psbuf->st_ex_atime);
 133         /* Last write time. */
 134         put_long_date_timespec(TIMESTAMP_SET_NT_OR_BETTER,
 135                                (char *)buf+16,
 136                                psbuf->st_ex_mtime);
 137         /* Change time. */
 138         put_long_date_timespec(TIMESTAMP_SET_NT_OR_BETTER,
 139                                (char *)buf+24,
 140                                psbuf->st_ex_ctime);
 141
 142         /* File size 64 Bit */
 143         SOFF_T(buf,32, get_file_size_stat(psbuf));
 144
 145         /* Number of bytes used on disk - 64 Bit */
 146         SOFF_T(buf,40,SMB_VFS_GET_ALLOC_SIZE(conn,NULL,psbuf));
 147
 148         /* DOS attributes */
 149         if (S_ISREG(psbuf->st_ex_mode)) {
 150                 PUSH_LE_U32(buf, 48, dos_attributes);
 151         } else if (S_ISDIR(psbuf->st_ex_mode)) {
 152                 PUSH_LE_U32(buf, 48, dos_attributes|FILE_ATTRIBUTE_DIRECTORY);
 153         } else {
 154                 /*
 155                  * All non-directory or regular files are reported
 156                  * as reparse points. Client may or may not be able
 157                  * to access these.
 158                  */
 159                 PUSH_LE_U32(buf, 48, FILE_ATTRIBUTE_REPARSE_POINT);
 160         }
 161
 162         /* Add the inode and dev (16 bytes). */
 163         PUSH_LE_U64(buf, 52, file_id);
 164         PUSH_LE_U64(buf, 60, psbuf->st_ex_dev);
 165
 166         /*
 167          * Append a POSIX create context (variable bytes).
 168          */
 169         smb2_posix_cc_info(
 170                 conn,
 171                 reparse_tag,
 172                 psbuf,
 173                 &owner,
 174                 &group,
 175                 buf + 68,
 176                 cc_len);
 177
 178         return cc_len + 68;
 179 }