source3/modules/vfs_acl_tdb.c

   1 /*
   2  * Store Windows ACLs in a tdb.
   3  *
   4  * Copyright (C) Volker Lendecke, 2008
   5  * Copyright (C) Jeremy Allison, 2008
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 /* NOTE: This is an experimental module, not yet finished. JRA. */
  22
  23 #include "includes.h"
  24 #include "librpc/gen_ndr/xattr.h"
  25 #include "librpc/gen_ndr/ndr_xattr.h"
  26 #include "../lib/crypto/crypto.h"
  27 #include "dbwrap.h"
  28
  29 #undef DBGC_CLASS
  30 #define DBGC_CLASS DBGC_VFS
  31
  32 #define ACL_MODULE_NAME "acl_tdb"
  33 #include "modules/vfs_acl_common.c"
  34
  35 static unsigned int ref_count;
  36 static struct db_context *acl_db;
  37
  38 /*******************************************************************
  39  Open acl_db if not already open, increment ref count.
  40 *******************************************************************/
  41
  42 static bool acl_tdb_init(void)
  43 {
  44         char *dbname;
  45
  46         if (acl_db) {
  47                 ref_count++;
  48                 return true;
  49         }
  50
  51         dbname = state_path("file_ntacls.tdb");
  52
  53         if (dbname == NULL) {
  54                 errno = ENOSYS;
  55                 return false;
  56         }
  57
  58         become_root();
  59         acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
  60         unbecome_root();
  61
  62         if (acl_db == NULL) {
  63 #if defined(ENOTSUP)
  64                 errno = ENOTSUP;
  65 #else
  66                 errno = ENOSYS;
  67 #endif
  68                 TALLOC_FREE(dbname);
  69                 return false;
  70         }
  71
  72         ref_count++;
  73         TALLOC_FREE(dbname);
  74         return true;
  75 }
  76
  77 /*******************************************************************
  78  Lower ref count and close acl_db if zero.
  79 *******************************************************************/
  80
  81 static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
  82 {
  83         SMB_VFS_NEXT_DISCONNECT(handle);
  84         ref_count--;
  85         if (ref_count == 0) {
  86                 TALLOC_FREE(acl_db);
  87         }
  88 }
  89
  90 /*******************************************************************
  91  Fetch_lock the tdb acl record for a file
  92 *******************************************************************/
  93
  94 static struct db_record *acl_tdb_lock(TALLOC_CTX *mem_ctx,
  95                                         struct db_context *db,
  96                                         const struct file_id *id)
  97 {
  98         uint8 id_buf[16];
  99
 100         /* For backwards compatibility only store the dev/inode. */
 101         push_file_id_16((char *)id_buf, id);
 102         return db->fetch_locked(db,
 103                                 mem_ctx,
 104                                 make_tdb_data(id_buf,
 105                                         sizeof(id_buf)));
 106 }
 107
 108 /*******************************************************************
 109  Delete the tdb acl record for a file
 110 *******************************************************************/
 111
 112 static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
 113                                 struct db_context *db,
 114                                 SMB_STRUCT_STAT *psbuf)
 115 {
 116         NTSTATUS status;
 117         struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
 118         struct db_record *rec = acl_tdb_lock(talloc_tos(), db, &id);
 119
 120         /*
 121          * If rec == NULL there's not much we can do about it
 122          */
 123
 124         if (rec == NULL) {
 125                 DEBUG(10,("acl_tdb_delete: rec == NULL\n"));
 126                 TALLOC_FREE(rec);
 127                 return NT_STATUS_OK;
 128         }
 129
 130         status = rec->delete_rec(rec);
 131         TALLOC_FREE(rec);
 132         return status;
 133 }
 134
 135 /*******************************************************************
 136  Pull a security descriptor into a DATA_BLOB from a tdb store.
 137 *******************************************************************/
 138
 139 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
 140                         vfs_handle_struct *handle,
 141                         files_struct *fsp,
 142                         const char *name,
 143                         DATA_BLOB *pblob)
 144 {
 145         uint8 id_buf[16];
 146         TDB_DATA data;
 147         struct file_id id;
 148         struct db_context *db = acl_db;
 149         NTSTATUS status = NT_STATUS_OK;
 150         SMB_STRUCT_STAT sbuf;
 151
 152         ZERO_STRUCT(sbuf);
 153
 154         if (fsp) {
 155                 status = vfs_stat_fsp(fsp);
 156                 sbuf = fsp->fsp_name->st;
 157         } else {
 158                 int ret = vfs_stat_smb_fname(handle->conn, name, &sbuf);
 159                 if (ret == -1) {
 160                         status = map_nt_error_from_unix(errno);
 161                 }
 162         }
 163
 164         if (!NT_STATUS_IS_OK(status)) {
 165                 return status;
 166         }
 167
 168         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 169
 170         /* For backwards compatibility only store the dev/inode. */
 171         push_file_id_16((char *)id_buf, &id);
 172
 173         if (db->fetch(db,
 174                         ctx,
 175                         make_tdb_data(id_buf, sizeof(id_buf)),
 176                         &data) == -1) {
 177                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 178         }
 179
 180         pblob->data = data.dptr;
 181         pblob->length = data.dsize;
 182
 183         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 184                 (unsigned int)data.dsize, name ));
 185
 186         if (pblob->length == 0 || pblob->data == NULL) {
 187                 return NT_STATUS_NOT_FOUND;
 188         }
 189         return NT_STATUS_OK;
 190 }
 191
 192 /*******************************************************************
 193  Store a DATA_BLOB into a tdb record given an fsp pointer.
 194 *******************************************************************/
 195
 196 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 197                                 files_struct *fsp,
 198                                 DATA_BLOB *pblob)
 199 {
 200         uint8 id_buf[16];
 201         struct file_id id;
 202         TDB_DATA data;
 203         struct db_context *db = acl_db;
 204         struct db_record *rec;
 205         NTSTATUS status;
 206
 207         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 208                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 209
 210         status = vfs_stat_fsp(fsp);
 211         if (!NT_STATUS_IS_OK(status)) {
 212                 return status;
 213         }
 214
 215         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 216
 217         /* For backwards compatibility only store the dev/inode. */
 218         push_file_id_16((char *)id_buf, &id);
 219         rec = db->fetch_locked(db, talloc_tos(),
 220                                 make_tdb_data(id_buf,
 221                                         sizeof(id_buf)));
 222         if (rec == NULL) {
 223                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 224                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 225         }
 226         data.dptr = pblob->data;
 227         data.dsize = pblob->length;
 228         return rec->store(rec, data, 0);
 229 }
 230
 231 /*********************************************************************
 232  On unlink we need to delete the tdb record (if using tdb).
 233 *********************************************************************/
 234
 235 static int unlink_acl_tdb(vfs_handle_struct *handle,
 236                           const struct smb_filename *smb_fname)
 237 {
 238         struct smb_filename *smb_fname_tmp = NULL;
 239         struct db_context *db = acl_db;
 240         NTSTATUS status;
 241         int ret = -1;
 242
 243         status = copy_smb_filename(talloc_tos(), smb_fname, &smb_fname_tmp);
 244         if (!NT_STATUS_IS_OK(status)) {
 245                 errno = map_errno_from_nt_status(status);
 246                 goto out;
 247         }
 248
 249         if (lp_posix_pathnames()) {
 250                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 251         } else {
 252                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 253         }
 254
 255         if (ret == -1) {
 256                 goto out;
 257         }
 258
 259         ret = unlink_acl_common(handle, smb_fname_tmp);
 260
 261         if (ret == -1) {
 262                 goto out;
 263         }
 264
 265         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 266  out:
 267         return ret;
 268 }
 269
 270 /*********************************************************************
 271  On rmdir we need to delete the tdb record (if using tdb).
 272 *********************************************************************/
 273
 274 static int rmdir_acl_tdb(vfs_handle_struct *handle, const char *path)
 275 {
 276
 277         SMB_STRUCT_STAT sbuf;
 278         struct db_context *db = acl_db;
 279         int ret = -1;
 280
 281         if (lp_posix_pathnames()) {
 282                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 283         } else {
 284                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 285         }
 286
 287         if (ret == -1) {
 288                 return -1;
 289         }
 290
 291         ret = rmdir_acl_common(handle, path);
 292         if (ret == -1) {
 293                 return -1;
 294         }
 295
 296         acl_tdb_delete(handle, db, &sbuf);
 297         return 0;
 298 }
 299
 300 /*******************************************************************
 301  Handle opening the storage tdb if so configured.
 302 *******************************************************************/
 303
 304 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 305                                 const char *service,
 306                                 const char *user)
 307 {
 308         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 309
 310         if (ret < 0) {
 311                 return ret;
 312         }
 313
 314         if (!acl_tdb_init()) {
 315                 SMB_VFS_NEXT_DISCONNECT(handle);
 316                 return -1;
 317         }
 318
 319         /* Ensure we have the parameters correct if we're
 320          * using this module. */
 321         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 322                 "'dos filemode = true' and "
 323                 "'force unknown acl user = true' for service %s\n",
 324                 service ));
 325
 326         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 327         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 328         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 329
 330         return 0;
 331 }
 332
 333 /*********************************************************************
 334  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 335 *********************************************************************/
 336
 337 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
 338                               const char *path,
 339                               SMB_ACL_TYPE_T type,
 340                               SMB_ACL_T theacl)
 341 {
 342         SMB_STRUCT_STAT sbuf;
 343         struct db_context *db = acl_db;
 344         int ret = -1;
 345
 346         if (lp_posix_pathnames()) {
 347                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 348         } else {
 349                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 350         }
 351
 352         if (ret == -1) {
 353                 return -1;
 354         }
 355
 356         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
 357                                                 path,
 358                                                 type,
 359                                                 theacl);
 360         if (ret == -1) {
 361                 return -1;
 362         }
 363
 364         acl_tdb_delete(handle, db, &sbuf);
 365         return 0;
 366 }
 367
 368 /*********************************************************************
 369  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 370 *********************************************************************/
 371
 372 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 373                             files_struct *fsp,
 374                             SMB_ACL_T theacl)
 375 {
 376         struct db_context *db = acl_db;
 377         NTSTATUS status;
 378         int ret;
 379
 380         status = vfs_stat_fsp(fsp);
 381         if (!NT_STATUS_IS_OK(status)) {
 382                 return -1;
 383         }
 384
 385         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 386                                                 fsp,
 387                                                 theacl);
 388         if (ret == -1) {
 389                 return -1;
 390         }
 391
 392         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 393         return 0;
 394 }
 395
 396 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 397         .connect_fn = connect_acl_tdb,
 398         .disconnect = disconnect_acl_tdb,
 399         .opendir = opendir_acl_common,
 400         .mkdir = mkdir_acl_common,
 401         .open = open_acl_common,
 402         .create_file = create_file_acl_common,
 403         .unlink = unlink_acl_tdb,
 404         .rmdir = rmdir_acl_tdb,
 405         .fget_nt_acl = fget_nt_acl_common,
 406         .get_nt_acl = get_nt_acl_common,
 407         .fset_nt_acl = fset_nt_acl_common,
 408         .sys_acl_set_file = sys_acl_set_file_tdb,
 409         .sys_acl_set_fd = sys_acl_set_fd_tdb
 410 };
 411
 412 NTSTATUS vfs_acl_tdb_init(void)
 413 {
 414         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 415                                 &vfs_acl_tdb_fns);
 416 }