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 "smbd/smbd.h"
  25 #include "system/filesys.h"
  26 #include "librpc/gen_ndr/xattr.h"
  27 #include "librpc/gen_ndr/ndr_xattr.h"
  28 #include "../lib/crypto/crypto.h"
  29 #include "dbwrap.h"
  30 #include "dbwrap/dbwrap_open.h"
  31 #include "auth.h"
  32 #include "util_tdb.h"
  33
  34 #undef DBGC_CLASS
  35 #define DBGC_CLASS DBGC_VFS
  36
  37 #define ACL_MODULE_NAME "acl_tdb"
  38 #include "modules/vfs_acl_common.c"
  39
  40 static unsigned int ref_count;
  41 static struct db_context *acl_db;
  42
  43 /*******************************************************************
  44  Open acl_db if not already open, increment ref count.
  45 *******************************************************************/
  46
  47 static bool acl_tdb_init(void)
  48 {
  49         char *dbname;
  50
  51         if (acl_db) {
  52                 ref_count++;
  53                 return true;
  54         }
  55
  56         dbname = state_path("file_ntacls.tdb");
  57
  58         if (dbname == NULL) {
  59                 errno = ENOSYS;
  60                 return false;
  61         }
  62
  63         become_root();
  64         acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
  65         unbecome_root();
  66
  67         if (acl_db == NULL) {
  68 #if defined(ENOTSUP)
  69                 errno = ENOTSUP;
  70 #else
  71                 errno = ENOSYS;
  72 #endif
  73                 TALLOC_FREE(dbname);
  74                 return false;
  75         }
  76
  77         ref_count++;
  78         TALLOC_FREE(dbname);
  79         return true;
  80 }
  81
  82 /*******************************************************************
  83  Lower ref count and close acl_db if zero.
  84 *******************************************************************/
  85
  86 static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
  87 {
  88         SMB_VFS_NEXT_DISCONNECT(handle);
  89         ref_count--;
  90         if (ref_count == 0) {
  91                 TALLOC_FREE(acl_db);
  92         }
  93 }
  94
  95 /*******************************************************************
  96  Fetch_lock the tdb acl record for a file
  97 *******************************************************************/
  98
  99 static struct db_record *acl_tdb_lock(TALLOC_CTX *mem_ctx,
 100                                         struct db_context *db,
 101                                         const struct file_id *id)
 102 {
 103         uint8 id_buf[16];
 104
 105         /* For backwards compatibility only store the dev/inode. */
 106         push_file_id_16((char *)id_buf, id);
 107         return db->fetch_locked(db,
 108                                 mem_ctx,
 109                                 make_tdb_data(id_buf,
 110                                         sizeof(id_buf)));
 111 }
 112
 113 /*******************************************************************
 114  Delete the tdb acl record for a file
 115 *******************************************************************/
 116
 117 static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
 118                                 struct db_context *db,
 119                                 SMB_STRUCT_STAT *psbuf)
 120 {
 121         NTSTATUS status;
 122         struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
 123         struct db_record *rec = acl_tdb_lock(talloc_tos(), db, &id);
 124
 125         /*
 126          * If rec == NULL there's not much we can do about it
 127          */
 128
 129         if (rec == NULL) {
 130                 DEBUG(10,("acl_tdb_delete: rec == NULL\n"));
 131                 TALLOC_FREE(rec);
 132                 return NT_STATUS_OK;
 133         }
 134
 135         status = rec->delete_rec(rec);
 136         TALLOC_FREE(rec);
 137         return status;
 138 }
 139
 140 /*******************************************************************
 141  Pull a security descriptor into a DATA_BLOB from a tdb store.
 142 *******************************************************************/
 143
 144 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
 145                         vfs_handle_struct *handle,
 146                         files_struct *fsp,
 147                         const char *name,
 148                         DATA_BLOB *pblob)
 149 {
 150         uint8 id_buf[16];
 151         TDB_DATA data;
 152         struct file_id id;
 153         struct db_context *db = acl_db;
 154         NTSTATUS status = NT_STATUS_OK;
 155         SMB_STRUCT_STAT sbuf;
 156
 157         ZERO_STRUCT(sbuf);
 158
 159         if (fsp) {
 160                 status = vfs_stat_fsp(fsp);
 161                 sbuf = fsp->fsp_name->st;
 162         } else {
 163                 int ret = vfs_stat_smb_fname(handle->conn, name, &sbuf);
 164                 if (ret == -1) {
 165                         status = map_nt_error_from_unix(errno);
 166                 }
 167         }
 168
 169         if (!NT_STATUS_IS_OK(status)) {
 170                 return status;
 171         }
 172
 173         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
 174
 175         /* For backwards compatibility only store the dev/inode. */
 176         push_file_id_16((char *)id_buf, &id);
 177
 178         if (db->fetch(db,
 179                         ctx,
 180                         make_tdb_data(id_buf, sizeof(id_buf)),
 181                         &data) != 0) {
 182                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 183         }
 184
 185         pblob->data = data.dptr;
 186         pblob->length = data.dsize;
 187
 188         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
 189                 (unsigned int)data.dsize, name ));
 190
 191         if (pblob->length == 0 || pblob->data == NULL) {
 192                 return NT_STATUS_NOT_FOUND;
 193         }
 194         return NT_STATUS_OK;
 195 }
 196
 197 /*******************************************************************
 198  Store a DATA_BLOB into a tdb record given an fsp pointer.
 199 *******************************************************************/
 200
 201 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
 202                                 files_struct *fsp,
 203                                 DATA_BLOB *pblob)
 204 {
 205         uint8 id_buf[16];
 206         struct file_id id;
 207         TDB_DATA data;
 208         struct db_context *db = acl_db;
 209         struct db_record *rec;
 210         NTSTATUS status;
 211
 212         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
 213                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
 214
 215         status = vfs_stat_fsp(fsp);
 216         if (!NT_STATUS_IS_OK(status)) {
 217                 return status;
 218         }
 219
 220         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
 221
 222         /* For backwards compatibility only store the dev/inode. */
 223         push_file_id_16((char *)id_buf, &id);
 224         rec = db->fetch_locked(db, talloc_tos(),
 225                                 make_tdb_data(id_buf,
 226                                         sizeof(id_buf)));
 227         if (rec == NULL) {
 228                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
 229                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 230         }
 231         data.dptr = pblob->data;
 232         data.dsize = pblob->length;
 233         return rec->store(rec, data, 0);
 234 }
 235
 236 /*********************************************************************
 237  On unlink we need to delete the tdb record (if using tdb).
 238 *********************************************************************/
 239
 240 static int unlink_acl_tdb(vfs_handle_struct *handle,
 241                           const struct smb_filename *smb_fname)
 242 {
 243         struct smb_filename *smb_fname_tmp = NULL;
 244         struct db_context *db = acl_db;
 245         NTSTATUS status;
 246         int ret = -1;
 247
 248         status = copy_smb_filename(talloc_tos(), smb_fname, &smb_fname_tmp);
 249         if (!NT_STATUS_IS_OK(status)) {
 250                 errno = map_errno_from_nt_status(status);
 251                 goto out;
 252         }
 253
 254         if (lp_posix_pathnames()) {
 255                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
 256         } else {
 257                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
 258         }
 259
 260         if (ret == -1) {
 261                 goto out;
 262         }
 263
 264         ret = unlink_acl_common(handle, smb_fname_tmp);
 265
 266         if (ret == -1) {
 267                 goto out;
 268         }
 269
 270         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
 271  out:
 272         return ret;
 273 }
 274
 275 /*********************************************************************
 276  On rmdir we need to delete the tdb record (if using tdb).
 277 *********************************************************************/
 278
 279 static int rmdir_acl_tdb(vfs_handle_struct *handle, const char *path)
 280 {
 281
 282         SMB_STRUCT_STAT sbuf;
 283         struct db_context *db = acl_db;
 284         int ret = -1;
 285
 286         if (lp_posix_pathnames()) {
 287                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 288         } else {
 289                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 290         }
 291
 292         if (ret == -1) {
 293                 return -1;
 294         }
 295
 296         ret = rmdir_acl_common(handle, path);
 297         if (ret == -1) {
 298                 return -1;
 299         }
 300
 301         acl_tdb_delete(handle, db, &sbuf);
 302         return 0;
 303 }
 304
 305 /*******************************************************************
 306  Handle opening the storage tdb if so configured.
 307 *******************************************************************/
 308
 309 static int connect_acl_tdb(struct vfs_handle_struct *handle,
 310                                 const char *service,
 311                                 const char *user)
 312 {
 313         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
 314
 315         if (ret < 0) {
 316                 return ret;
 317         }
 318
 319         if (!acl_tdb_init()) {
 320                 SMB_VFS_NEXT_DISCONNECT(handle);
 321                 return -1;
 322         }
 323
 324         /* Ensure we have the parameters correct if we're
 325          * using this module. */
 326         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
 327                 "'dos filemode = true' and "
 328                 "'force unknown acl user = true' for service %s\n",
 329                 service ));
 330
 331         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
 332         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
 333         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
 334
 335         return 0;
 336 }
 337
 338 /*********************************************************************
 339  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 340 *********************************************************************/
 341
 342 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
 343                               const char *path,
 344                               SMB_ACL_TYPE_T type,
 345                               SMB_ACL_T theacl)
 346 {
 347         SMB_STRUCT_STAT sbuf;
 348         struct db_context *db = acl_db;
 349         int ret = -1;
 350
 351         if (lp_posix_pathnames()) {
 352                 ret = vfs_lstat_smb_fname(handle->conn, path, &sbuf);
 353         } else {
 354                 ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
 355         }
 356
 357         if (ret == -1) {
 358                 return -1;
 359         }
 360
 361         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
 362                                                 path,
 363                                                 type,
 364                                                 theacl);
 365         if (ret == -1) {
 366                 return -1;
 367         }
 368
 369         acl_tdb_delete(handle, db, &sbuf);
 370         return 0;
 371 }
 372
 373 /*********************************************************************
 374  Remove a Windows ACL - we're setting the underlying POSIX ACL.
 375 *********************************************************************/
 376
 377 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
 378                             files_struct *fsp,
 379                             SMB_ACL_T theacl)
 380 {
 381         struct db_context *db = acl_db;
 382         NTSTATUS status;
 383         int ret;
 384
 385         status = vfs_stat_fsp(fsp);
 386         if (!NT_STATUS_IS_OK(status)) {
 387                 return -1;
 388         }
 389
 390         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
 391                                                 fsp,
 392                                                 theacl);
 393         if (ret == -1) {
 394                 return -1;
 395         }
 396
 397         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
 398         return 0;
 399 }
 400
 401 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
 402         .connect_fn = connect_acl_tdb,
 403         .disconnect = disconnect_acl_tdb,
 404         .opendir = opendir_acl_common,
 405         .mkdir = mkdir_acl_common,
 406         .rmdir = rmdir_acl_tdb,
 407         .open_fn = open_acl_common,
 408         .create_file = create_file_acl_common,
 409         .unlink = unlink_acl_tdb,
 410         .chmod = chmod_acl_module_common,
 411         .fchmod = fchmod_acl_module_common,
 412         .fget_nt_acl = fget_nt_acl_common,
 413         .get_nt_acl = get_nt_acl_common,
 414         .fset_nt_acl = fset_nt_acl_common,
 415         .chmod_acl = chmod_acl_acl_module_common,
 416         .fchmod_acl = fchmod_acl_acl_module_common,
 417         .sys_acl_set_file = sys_acl_set_file_tdb,
 418         .sys_acl_set_fd = sys_acl_set_fd_tdb
 419 };
 420
 421 NTSTATUS vfs_acl_tdb_init(void)
 422 {
 423         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
 424                                 &vfs_acl_tdb_fns);
 425 }