source/libsmb/smb_share_modes.c

   1 /*
   2    Samba share mode database library external interface library.
   3    Used by non-Samba products needing access to the Samba share mode db.
   4
   5    Copyright (C) Jeremy Allison 2005 - 2006
   6
   7    sharemodes_procid functions (C) Copyright (C) Volker Lendecke 2005
   8
   9      ** NOTE! The following LGPL license applies to this module only.
  10      ** This does NOT imply that all of Samba is released
  11      ** under the LGPL
  12
  13    This library is free software; you can redistribute it and/or
  14    modify it under the terms of the GNU Lesser General Public
  15    License as published by the Free Software Foundation; either
  16    version 3 of the License, or (at your option) any later version.
  17
  18    This library is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21    Lesser General Public License for more details.
  22
  23    You should have received a copy of the GNU Lesser General Public
  24    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  25 */
  26
  27 #include "includes.h"
  28 #include "smb_share_modes.h"
  29
  30 /* Database context handle. */
  31 struct smbdb_ctx {
  32         TDB_CONTEXT *smb_tdb;
  33 };
  34
  35 /* Remove the paranoid malloc checker. */
  36 #ifdef malloc
  37 #undef malloc
  38 #endif
  39
  40 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx, uint64_t dev,
  41                                 uint64_t ino, const struct smb_share_mode_entry *new_entry,
  42                                 const char *sharepath, const char *filename);
  43
  44 static bool sharemodes_procid_equal(const struct server_id *p1, const struct server_id *p2)
  45 {
  46         return (p1->pid == p2->pid);
  47 }
  48
  49 static pid_t sharemodes_procid_to_pid(const struct server_id *proc)
  50 {
  51         return proc->pid;
  52 }
  53
  54 /*
  55  * open/close sharemode database.
  56  */
  57
  58 struct smbdb_ctx *smb_share_mode_db_open(const char *db_path)
  59 {
  60         struct smbdb_ctx *smb_db = (struct smbdb_ctx *)malloc(sizeof(struct smbdb_ctx));
  61
  62         if (!smb_db) {
  63                 return NULL;
  64         }
  65
  66         memset(smb_db, '\0', sizeof(struct smbdb_ctx));
  67
  68         smb_db->smb_tdb = tdb_open(db_path,
  69                                 0, TDB_DEFAULT|TDB_CLEAR_IF_FIRST,
  70                                 O_RDWR|O_CREAT,
  71                                 0644);
  72
  73         if (!smb_db->smb_tdb) {
  74                 free(smb_db);
  75                 return NULL;
  76         }
  77
  78         /* Should check that this is the correct version.... */
  79         return smb_db;
  80 }
  81
  82 /* key and data records in the tdb locking database */
  83 struct locking_key {
  84         SMB_DEV_T dev;
  85         SMB_INO_T inode;
  86 };
  87
  88 int smb_share_mode_db_close(struct smbdb_ctx *db_ctx)
  89 {
  90         int ret = tdb_close(db_ctx->smb_tdb);
  91         free(db_ctx);
  92         return ret;
  93 }
  94
  95 static TDB_DATA get_locking_key(uint64_t dev, uint64_t ino)
  96 {
  97         static struct locking_key lk;
  98         TDB_DATA ld;
  99
 100         memset(&lk, '\0', sizeof(struct locking_key));
 101         lk.dev = (SMB_DEV_T)dev;
 102         lk.inode = (SMB_INO_T)ino;
 103         ld.dptr = (uint8 *)&lk;
 104         ld.dsize = sizeof(lk);
 105         return ld;
 106 }
 107
 108 /*
 109  * lock/unlock entry in sharemode database.
 110  */
 111
 112 int smb_lock_share_mode_entry(struct smbdb_ctx *db_ctx,
 113                                 uint64_t dev,
 114                                 uint64_t ino)
 115 {
 116         return tdb_chainlock(db_ctx->smb_tdb, get_locking_key(dev, ino));
 117 }
 118
 119 int smb_unlock_share_mode_entry(struct smbdb_ctx *db_ctx,
 120                                 uint64_t dev,
 121                                 uint64_t ino)
 122 {
 123         return tdb_chainunlock(db_ctx->smb_tdb, get_locking_key(dev, ino));
 124 }
 125
 126 /*
 127  * Check if an external smb_share_mode_entry and an internal share_mode entry match.
 128  */
 129
 130 static int share_mode_entry_equal(const struct smb_share_mode_entry *e_entry,
 131                                 const struct share_mode_entry *entry)
 132 {
 133         return (sharemodes_procid_equal(&e_entry->pid, &entry->pid) &&
 134                 e_entry->file_id == (uint32_t)entry->share_file_id &&
 135                 e_entry->open_time.tv_sec == entry->time.tv_sec &&
 136                 e_entry->open_time.tv_usec == entry->time.tv_usec &&
 137                 e_entry->share_access == (uint32_t)entry->share_access &&
 138                 e_entry->access_mask == (uint32_t)entry->access_mask &&
 139                 e_entry->dev == entry->id.devid &&
 140                 e_entry->ino == entry->id.inode);
 141 }
 142
 143 /*
 144  * Create an internal Samba share_mode entry from an external smb_share_mode_entry.
 145  */
 146
 147 static void create_share_mode_entry(struct share_mode_entry *out,
 148                                 const struct smb_share_mode_entry *in)
 149 {
 150         memset(out, '\0', sizeof(struct share_mode_entry));
 151
 152         out->pid = in->pid;
 153         out->share_file_id = (unsigned long)in->file_id;
 154         out->time.tv_sec = in->open_time.tv_sec;
 155         out->time.tv_usec = in->open_time.tv_usec;
 156         out->share_access = in->share_access;
 157         out->access_mask = in->access_mask;
 158         out->id.devid = in->dev;
 159         out->id.inode = in->ino;
 160         out->uid = (uint32)geteuid();
 161         out->flags = 0;
 162 }
 163
 164 /*
 165  * Return the current share mode list for an open file.
 166  * This uses similar (but simplified) logic to locking/locking.c
 167  */
 168
 169 int smb_get_share_mode_entries(struct smbdb_ctx *db_ctx,
 170                                 uint64_t dev,
 171                                 uint64_t ino,
 172                                 struct smb_share_mode_entry **pp_list,
 173                                 unsigned char *p_delete_on_close)
 174 {
 175         TDB_DATA db_data;
 176         struct smb_share_mode_entry *list = NULL;
 177         int num_share_modes = 0;
 178         struct locking_data *ld = NULL; /* internal samba db state. */
 179         struct share_mode_entry *shares = NULL;
 180         size_t i;
 181         int list_num;
 182
 183         *pp_list = NULL;
 184         *p_delete_on_close = 0;
 185
 186         db_data = tdb_fetch(db_ctx->smb_tdb, get_locking_key(dev, ino));
 187         if (!db_data.dptr) {
 188                 return 0;
 189         }
 190
 191         ld = (struct locking_data *)db_data.dptr;
 192         num_share_modes = ld->u.s.num_share_mode_entries;
 193
 194         if (!num_share_modes) {
 195                 free(db_data.dptr);
 196                 return 0;
 197         }
 198
 199         list = (struct smb_share_mode_entry *)malloc(sizeof(struct smb_share_mode_entry)*num_share_modes);
 200         if (!list) {
 201                 free(db_data.dptr);
 202                 return -1;
 203         }
 204
 205         memset(list, '\0', num_share_modes * sizeof(struct smb_share_mode_entry));
 206
 207         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 208
 209         list_num = 0;
 210         for (i = 0; i < num_share_modes; i++) {
 211                 struct share_mode_entry *share = &shares[i];
 212                 struct smb_share_mode_entry *sme = &list[list_num];
 213                 struct server_id pid = share->pid;
 214
 215                 /* Check this process really exists. */
 216                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 217                         continue; /* No longer exists. */
 218                 }
 219
 220                 /* Ignore deferred open entries. */
 221                 if (share->op_type == DEFERRED_OPEN_ENTRY) {
 222                         continue;
 223                 }
 224
 225                 /* Copy into the external list. */
 226                 sme->dev = share->id.devid;
 227                 sme->ino = share->id.inode;
 228                 sme->share_access = (uint32_t)share->share_access;
 229                 sme->access_mask = (uint32_t)share->access_mask;
 230                 sme->open_time.tv_sec = share->time.tv_sec;
 231                 sme->open_time.tv_usec = share->time.tv_usec;
 232                 sme->file_id = (uint32_t)share->share_file_id;
 233                 sme->pid = share->pid;
 234                 list_num++;
 235         }
 236
 237         if (list_num == 0) {
 238                 free(db_data.dptr);
 239                 free(list);
 240                 return 0;
 241         }
 242
 243         *p_delete_on_close = ld->u.s.delete_on_close;
 244         *pp_list = list;
 245         free(db_data.dptr);
 246         return list_num;
 247 }
 248
 249 /*
 250  * Create an entry in the Samba share mode db.
 251  */
 252
 253 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx,
 254                                 uint64_t dev,
 255                                 uint64_t ino,
 256                                 const struct smb_share_mode_entry *new_entry,
 257                                 const char *sharepath, /* Must be absolute utf8 path. */
 258                                 const char *filename) /* Must be relative utf8 path. */
 259 {
 260         TDB_DATA db_data;
 261         TDB_DATA locking_key =  get_locking_key(dev, ino);
 262         int orig_num_share_modes = 0;
 263         struct locking_data *ld = NULL; /* internal samba db state. */
 264         struct share_mode_entry *shares = NULL;
 265         uint8 *new_data_p = NULL;
 266         size_t new_data_size = 0;
 267
 268         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 269         if (!db_data.dptr) {
 270                 /* We must create the entry. */
 271                 db_data.dptr = (uint8 *)malloc(
 272                         sizeof(struct locking_data) +
 273                         sizeof(struct share_mode_entry) +
 274                         strlen(sharepath) + 1 +
 275                         strlen(filename) + 1);
 276                 if (!db_data.dptr) {
 277                         return -1;
 278                 }
 279                 ld = (struct locking_data *)db_data.dptr;
 280                 memset(ld, '\0', sizeof(struct locking_data));
 281                 ld->u.s.num_share_mode_entries = 1;
 282                 ld->u.s.delete_on_close = 0;
 283                 ld->u.s.delete_token_size = 0;
 284                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 285                 create_share_mode_entry(shares, new_entry);
 286
 287                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry),
 288                         sharepath,
 289                         strlen(sharepath) + 1);
 290                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 291                         strlen(sharepath) + 1,
 292                         filename,
 293                         strlen(filename) + 1);
 294
 295                 db_data.dsize = sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 296                                         strlen(sharepath) + 1 +
 297                                         strlen(filename) + 1;
 298                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) == -1) {
 299                         free(db_data.dptr);
 300                         return -1;
 301                 }
 302                 free(db_data.dptr);
 303                 return 0;
 304         }
 305
 306         /* Entry exists, we must add a new entry. */
 307         new_data_p = (uint8 *)malloc(
 308                 db_data.dsize + sizeof(struct share_mode_entry));
 309         if (!new_data_p) {
 310                 free(db_data.dptr);
 311                 return -1;
 312         }
 313
 314         ld = (struct locking_data *)db_data.dptr;
 315         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 316
 317         /* Copy the original data. */
 318         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)));
 319
 320         /* Add in the new share mode */
 321         shares = (struct share_mode_entry *)(new_data_p + sizeof(struct locking_data) +
 322                         (orig_num_share_modes * sizeof(struct share_mode_entry)));
 323
 324         create_share_mode_entry(shares, new_entry);
 325
 326         ld = (struct locking_data *)new_data_p;
 327         ld->u.s.num_share_mode_entries++;
 328
 329         /* Append the original delete_token and filenames. */
 330         memcpy(new_data_p + sizeof(struct locking_data) + (ld->u.s.num_share_mode_entries * sizeof(struct share_mode_entry)),
 331                 db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)),
 332                 db_data.dsize - sizeof(struct locking_data) - (orig_num_share_modes * sizeof(struct share_mode_entry)));
 333
 334         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 335
 336         free(db_data.dptr);
 337
 338         db_data.dptr = new_data_p;
 339         db_data.dsize = new_data_size;
 340
 341         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 342                 free(db_data.dptr);
 343                 return -1;
 344         }
 345         free(db_data.dptr);
 346         return 0;
 347 }
 348
 349 /*
 350  * Create an entry in the Samba share mode db. Original interface - doesn't
 351  * Distinguish between share path and filename. Fudge this by using a
 352  * sharepath of / and a relative filename of (filename+1).
 353  */
 354
 355 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 356                                 uint64_t dev,
 357                                 uint64_t ino,
 358                                 const struct smb_share_mode_entry *new_entry,
 359                                 const char *filename) /* Must be absolute utf8 path. */
 360 {
 361         if (*filename != '/') {
 362                 abort();
 363         }
 364         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, new_entry,
 365                                                 "/", &filename[1]);
 366 }
 367
 368 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 369                                 uint64_t dev,
 370                                 uint64_t ino,
 371                                 const struct smb_share_mode_entry *del_entry)
 372 {
 373         TDB_DATA db_data;
 374         TDB_DATA locking_key =  get_locking_key(dev, ino);
 375         int orig_num_share_modes = 0;
 376         struct locking_data *ld = NULL; /* internal samba db state. */
 377         struct share_mode_entry *shares = NULL;
 378         uint8 *new_data_p = NULL;
 379         size_t remaining_size = 0;
 380         size_t i, num_share_modes;
 381         const uint8 *remaining_ptr = NULL;
 382
 383         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 384         if (!db_data.dptr) {
 385                 return -1; /* Error - missing entry ! */
 386         }
 387
 388         ld = (struct locking_data *)db_data.dptr;
 389         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 390         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 391
 392         if (orig_num_share_modes == 1) {
 393                 /* Only one entry - better be ours... */
 394                 if (!share_mode_entry_equal(del_entry, shares)) {
 395                         /* Error ! We can't delete someone else's entry ! */
 396                         free(db_data.dptr);
 397                         return -1;
 398                 }
 399                 /* It's ours - just remove the entire record. */
 400                 free(db_data.dptr);
 401                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 402         }
 403
 404         /* More than one - allocate a new record minus the one we'll delete. */
 405         new_data_p = (uint8 *)malloc(
 406                 db_data.dsize - sizeof(struct share_mode_entry));
 407         if (!new_data_p) {
 408                 free(db_data.dptr);
 409                 return -1;
 410         }
 411
 412         /* Copy the header. */
 413         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data));
 414
 415         num_share_modes = 0;
 416         for (i = 0; i < orig_num_share_modes; i++) {
 417                 struct share_mode_entry *share = &shares[i];
 418                 struct server_id pid = share->pid;
 419
 420                 /* Check this process really exists. */
 421                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 422                         continue; /* No longer exists. */
 423                 }
 424
 425                 if (share_mode_entry_equal(del_entry, share)) {
 426                         continue; /* This is our delete taget. */
 427                 }
 428
 429                 memcpy(new_data_p + sizeof(struct locking_data) +
 430                                 (num_share_modes * sizeof(struct share_mode_entry)),
 431                         share, sizeof(struct share_mode_entry) );
 432
 433                 num_share_modes++;
 434         }
 435
 436         if (num_share_modes == 0) {
 437                 /* None left after pruning. Delete record. */
 438                 free(db_data.dptr);
 439                 free(new_data_p);
 440                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 441         }
 442
 443         /* Copy any delete token plus the terminating filenames. */
 444         remaining_ptr = db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry));
 445         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 446
 447         memcpy(new_data_p + sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)),
 448                 remaining_ptr,
 449                 remaining_size);
 450
 451         free(db_data.dptr);
 452
 453         db_data.dptr = new_data_p;
 454
 455         /* Re-save smaller record. */
 456         ld = (struct locking_data *)db_data.dptr;
 457         ld->u.s.num_share_mode_entries = num_share_modes;
 458
 459         db_data.dsize = sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)) + remaining_size;
 460
 461         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 462                 free(db_data.dptr);
 463                 return -1;
 464         }
 465         free(db_data.dptr);
 466         return 0;
 467 }
 468
 469 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 470                                 uint64_t dev,
 471                                 uint64_t ino,
 472                                 const struct smb_share_mode_entry *set_entry,
 473                                 const struct smb_share_mode_entry *new_entry)
 474 {
 475         TDB_DATA db_data;
 476         TDB_DATA locking_key =  get_locking_key(dev, ino);
 477         int num_share_modes = 0;
 478         struct locking_data *ld = NULL; /* internal samba db state. */
 479         struct share_mode_entry *shares = NULL;
 480         size_t i;
 481         int found_entry = 0;
 482
 483         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 484         if (!db_data.dptr) {
 485                 return -1; /* Error - missing entry ! */
 486         }
 487
 488         ld = (struct locking_data *)db_data.dptr;
 489         num_share_modes = ld->u.s.num_share_mode_entries;
 490         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 491
 492         for (i = 0; i < num_share_modes; i++) {
 493                 struct share_mode_entry *share = &shares[i];
 494                 struct server_id pid = share->pid;
 495
 496                 /* Check this process really exists. */
 497                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 498                         continue; /* No longer exists. */
 499                 }
 500
 501                 if (share_mode_entry_equal(set_entry, share)) {
 502                         create_share_mode_entry(share, new_entry);
 503                         found_entry = 1;
 504                         break;
 505                 }
 506         }
 507
 508         if (!found_entry) {
 509                 free(db_data.dptr);
 510                 return -1;
 511         }
 512
 513         /* Save modified data. */
 514         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 515                 free(db_data.dptr);
 516                 return -1;
 517         }
 518         free(db_data.dptr);
 519         return 0;
 520 }