source3/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, uint64_t extid,
  42                                 const struct smb_share_mode_entry *new_entry,
  43                                 const char *sharepath, const char *filename);
  44
  45 static bool sharemodes_procid_equal(const struct server_id *p1, const struct server_id *p2)
  46 {
  47         return (p1->pid == p2->pid);
  48 }
  49
  50 static pid_t sharemodes_procid_to_pid(const struct server_id *proc)
  51 {
  52         return proc->pid;
  53 }
  54
  55 /*
  56  * open/close sharemode database.
  57  */
  58
  59 struct smbdb_ctx *smb_share_mode_db_open(const char *db_path)
  60 {
  61         struct smbdb_ctx *smb_db = (struct smbdb_ctx *)malloc(sizeof(struct smbdb_ctx));
  62
  63         if (!smb_db) {
  64                 return NULL;
  65         }
  66
  67         memset(smb_db, '\0', sizeof(struct smbdb_ctx));
  68
  69         smb_db->smb_tdb = tdb_open(db_path,
  70                                 0, TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH,
  71                                 O_RDWR|O_CREAT,
  72                                 0644);
  73
  74         if (!smb_db->smb_tdb) {
  75                 free(smb_db);
  76                 return NULL;
  77         }
  78
  79         /* Should check that this is the correct version.... */
  80         return smb_db;
  81 }
  82
  83 /* key and data records in the tdb locking database */
  84 struct locking_key {
  85         SMB_DEV_T dev;
  86         SMB_INO_T inode;
  87         uint64_t extid;
  88 };
  89
  90 int smb_share_mode_db_close(struct smbdb_ctx *db_ctx)
  91 {
  92         int ret = tdb_close(db_ctx->smb_tdb);
  93         free(db_ctx);
  94         return ret;
  95 }
  96
  97 static TDB_DATA get_locking_key(struct locking_key *lk, uint64_t dev,
  98                                 uint64_t ino, uint64_t extid)
  99 {
 100         TDB_DATA ld;
 101
 102         memset(lk, '\0', sizeof(*lk));
 103         lk->dev = (SMB_DEV_T)dev;
 104         lk->inode = (SMB_INO_T)ino;
 105         lk->extid = extid;
 106         ld.dptr = (uint8 *)lk;
 107         ld.dsize = sizeof(*lk);
 108         return ld;
 109 }
 110
 111 /*
 112  * lock/unlock entry in sharemode database.
 113  */
 114
 115 int smb_lock_share_mode_entry(struct smbdb_ctx *db_ctx,
 116                                 uint64_t dev,
 117                                 uint64_t ino,
 118                                 uint64_t extid)
 119 {
 120         struct locking_key lk;
 121         return tdb_chainlock(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino,
 122                                                               extid));
 123 }
 124
 125 int smb_unlock_share_mode_entry(struct smbdb_ctx *db_ctx,
 126                                 uint64_t dev,
 127                                 uint64_t ino,
 128                                 uint64_t extid)
 129 {
 130         struct locking_key lk;
 131         return tdb_chainunlock(db_ctx->smb_tdb,
 132                                get_locking_key(&lk, dev, ino, extid));
 133 }
 134
 135 /*
 136  * Check if an external smb_share_mode_entry and an internal share_mode entry match.
 137  */
 138
 139 static int share_mode_entry_equal(const struct smb_share_mode_entry *e_entry,
 140                                 const struct share_mode_entry *entry)
 141 {
 142         return (sharemodes_procid_equal(&e_entry->pid, &entry->pid) &&
 143                 e_entry->file_id == (uint32_t)entry->share_file_id &&
 144                 e_entry->open_time.tv_sec == entry->time.tv_sec &&
 145                 e_entry->open_time.tv_usec == entry->time.tv_usec &&
 146                 e_entry->share_access == (uint32_t)entry->share_access &&
 147                 e_entry->access_mask == (uint32_t)entry->access_mask &&
 148                 e_entry->dev == entry->id.devid &&
 149                 e_entry->ino == entry->id.inode &&
 150                 e_entry->extid == entry->id.extid);
 151 }
 152
 153 /*
 154  * Create an internal Samba share_mode entry from an external smb_share_mode_entry.
 155  */
 156
 157 static void create_share_mode_entry(struct share_mode_entry *out,
 158                                 const struct smb_share_mode_entry *in,
 159                                 uint32_t name_hash)
 160 {
 161         memset(out, '\0', sizeof(struct share_mode_entry));
 162
 163         out->pid = in->pid;
 164         out->share_file_id = (unsigned long)in->file_id;
 165         out->time.tv_sec = in->open_time.tv_sec;
 166         out->time.tv_usec = in->open_time.tv_usec;
 167         out->share_access = in->share_access;
 168         out->access_mask = in->access_mask;
 169         out->id.devid = in->dev;
 170         out->id.inode = in->ino;
 171         out->id.extid = in->extid;
 172         out->uid = (uint32)geteuid();
 173         out->flags = 0;
 174         out->name_hash = name_hash;
 175 }
 176
 177 /*
 178  * Return the current share mode list for an open file.
 179  * This uses similar (but simplified) logic to locking/locking.c
 180  */
 181
 182 int smb_get_share_mode_entries(struct smbdb_ctx *db_ctx,
 183                                 uint64_t dev,
 184                                 uint64_t ino,
 185                                 uint64_t extid,
 186                                 struct smb_share_mode_entry **pp_list,
 187                                 unsigned char *p_delete_on_close)
 188 {
 189         struct locking_key lk;
 190         TDB_DATA db_data;
 191         struct smb_share_mode_entry *list = NULL;
 192         int num_share_modes = 0;
 193         struct locking_data *ld = NULL; /* internal samba db state. */
 194         struct share_mode_entry *shares = NULL;
 195         size_t i;
 196         int list_num;
 197
 198         *pp_list = NULL;
 199         *p_delete_on_close = 0;
 200
 201         db_data = tdb_fetch(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino,
 202                                                              extid));
 203         if (!db_data.dptr) {
 204                 return 0;
 205         }
 206
 207         ld = (struct locking_data *)db_data.dptr;
 208         num_share_modes = ld->u.s.num_share_mode_entries;
 209
 210         if (!num_share_modes) {
 211                 free(db_data.dptr);
 212                 return 0;
 213         }
 214
 215         list = (struct smb_share_mode_entry *)malloc(sizeof(struct smb_share_mode_entry)*num_share_modes);
 216         if (!list) {
 217                 free(db_data.dptr);
 218                 return -1;
 219         }
 220
 221         memset(list, '\0', num_share_modes * sizeof(struct smb_share_mode_entry));
 222
 223         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 224
 225         list_num = 0;
 226         for (i = 0; i < num_share_modes; i++) {
 227                 struct share_mode_entry *share = &shares[i];
 228                 struct smb_share_mode_entry *sme = &list[list_num];
 229                 struct server_id pid = share->pid;
 230
 231                 /* Check this process really exists. */
 232                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 233                         continue; /* No longer exists. */
 234                 }
 235
 236                 /* Ignore deferred open entries. */
 237                 if (share->op_type == DEFERRED_OPEN_ENTRY) {
 238                         continue;
 239                 }
 240
 241                 /* Copy into the external list. */
 242                 sme->dev = share->id.devid;
 243                 sme->ino = share->id.inode;
 244                 sme->extid = share->id.extid;
 245                 sme->share_access = (uint32_t)share->share_access;
 246                 sme->access_mask = (uint32_t)share->access_mask;
 247                 sme->open_time.tv_sec = share->time.tv_sec;
 248                 sme->open_time.tv_usec = share->time.tv_usec;
 249                 sme->file_id = (uint32_t)share->share_file_id;
 250                 sme->pid = share->pid;
 251                 list_num++;
 252         }
 253
 254         if (list_num == 0) {
 255                 free(db_data.dptr);
 256                 free(list);
 257                 return 0;
 258         }
 259
 260         *p_delete_on_close = ld->u.s.num_delete_token_entries != 0;
 261         *pp_list = list;
 262         free(db_data.dptr);
 263         return list_num;
 264 }
 265
 266 static uint32_t smb_name_hash(const char *sharepath, const char *filename, int *err)
 267 {
 268         TDB_DATA key;
 269         char *fullpath = NULL;
 270         size_t sharepath_size = strlen(sharepath);
 271         size_t filename_size = strlen(filename);
 272         uint32_t name_hash;
 273
 274         *err = 0;
 275         fullpath = (char *)malloc(sharepath_size + filename_size + 2);
 276         if (fullpath == NULL) {
 277                 *err = 1;
 278                 return 0;
 279         }
 280         memcpy(fullpath, sharepath, sharepath_size);
 281         fullpath[sharepath_size] = '/';
 282         memcpy(&fullpath[sharepath_size + 1], filename, filename_size + 1);
 283
 284         key.dptr = (uint8_t *)fullpath;
 285         key.dsize = strlen(fullpath) + 1;
 286         name_hash = tdb_jenkins_hash(&key);
 287         free(fullpath);
 288         return name_hash;
 289 }
 290
 291 /*
 292  * Create an entry in the Samba share mode db.
 293  */
 294
 295 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx,
 296                                 uint64_t dev,
 297                                 uint64_t ino,
 298                                 uint64_t extid,
 299                                 const struct smb_share_mode_entry *new_entry,
 300                                 const char *sharepath, /* Must be absolute utf8 path. */
 301                                 const char *filename) /* Must be relative utf8 path. */
 302 {
 303         TDB_DATA db_data;
 304         struct locking_key lk;
 305         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 306         int orig_num_share_modes = 0;
 307         struct locking_data *ld = NULL; /* internal samba db state. */
 308         struct share_mode_entry *shares = NULL;
 309         uint8 *new_data_p = NULL;
 310         size_t new_data_size = 0;
 311         int err = 0;
 312         uint32_t name_hash = smb_name_hash(sharepath, filename, &err);
 313
 314         if (err) {
 315                 return -1;
 316         }
 317
 318         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 319         if (!db_data.dptr) {
 320                 /* We must create the entry. */
 321                 db_data.dptr = (uint8 *)malloc(
 322                         sizeof(struct locking_data) +
 323                         sizeof(struct share_mode_entry) +
 324                         strlen(sharepath) + 1 +
 325                         strlen(filename) + 1);
 326                 if (!db_data.dptr) {
 327                         return -1;
 328                 }
 329                 ld = (struct locking_data *)db_data.dptr;
 330                 memset(ld, '\0', sizeof(struct locking_data));
 331                 ld->u.s.num_share_mode_entries = 1;
 332                 ld->u.s.num_delete_token_entries = 0;
 333                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 334                 create_share_mode_entry(shares, new_entry, name_hash);
 335
 336                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry),
 337                         sharepath,
 338                         strlen(sharepath) + 1);
 339                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 340                         strlen(sharepath) + 1,
 341                         filename,
 342                         strlen(filename) + 1);
 343
 344                 db_data.dsize = sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 345                                         strlen(sharepath) + 1 +
 346                                         strlen(filename) + 1;
 347                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) == -1) {
 348                         free(db_data.dptr);
 349                         return -1;
 350                 }
 351                 free(db_data.dptr);
 352                 return 0;
 353         }
 354
 355         /* Entry exists, we must add a new entry. */
 356         new_data_p = (uint8 *)malloc(
 357                 db_data.dsize + sizeof(struct share_mode_entry));
 358         if (!new_data_p) {
 359                 free(db_data.dptr);
 360                 return -1;
 361         }
 362
 363         ld = (struct locking_data *)db_data.dptr;
 364         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 365
 366         /* Copy the original data. */
 367         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)));
 368
 369         /* Add in the new share mode */
 370         shares = (struct share_mode_entry *)(new_data_p + sizeof(struct locking_data) +
 371                         (orig_num_share_modes * sizeof(struct share_mode_entry)));
 372
 373         create_share_mode_entry(shares, new_entry, name_hash);
 374
 375         ld = (struct locking_data *)new_data_p;
 376         ld->u.s.num_share_mode_entries++;
 377
 378         /* Append the original delete_tokens and filenames. */
 379         memcpy(new_data_p + sizeof(struct locking_data) + (ld->u.s.num_share_mode_entries * sizeof(struct share_mode_entry)),
 380                 db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)),
 381                 db_data.dsize - sizeof(struct locking_data) - (orig_num_share_modes * sizeof(struct share_mode_entry)));
 382
 383         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 384
 385         free(db_data.dptr);
 386
 387         db_data.dptr = new_data_p;
 388         db_data.dsize = new_data_size;
 389
 390         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 391                 free(db_data.dptr);
 392                 return -1;
 393         }
 394         free(db_data.dptr);
 395         return 0;
 396 }
 397
 398 /*
 399  * Create an entry in the Samba share mode db. Original interface - doesn't
 400  * Distinguish between share path and filename. Fudge this by using a
 401  * sharepath of / and a relative filename of (filename+1).
 402  */
 403
 404 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 405                                 uint64_t dev,
 406                                 uint64_t ino,
 407                                 uint64_t extid,
 408                                 const struct smb_share_mode_entry *new_entry,
 409                                 const char *filename) /* Must be absolute utf8 path. */
 410 {
 411         if (*filename != '/') {
 412                 abort();
 413         }
 414         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, extid, new_entry,
 415                                                 "/", &filename[1]);
 416 }
 417
 418 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 419                                 uint64_t dev,
 420                                 uint64_t ino,
 421                                 uint64_t extid,
 422                                 const struct smb_share_mode_entry *del_entry)
 423 {
 424         TDB_DATA db_data;
 425         struct locking_key lk;
 426         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 427         int orig_num_share_modes = 0;
 428         struct locking_data *ld = NULL; /* internal samba db state. */
 429         struct share_mode_entry *shares = NULL;
 430         uint8 *new_data_p = NULL;
 431         size_t remaining_size = 0;
 432         size_t i, num_share_modes;
 433         const uint8 *remaining_ptr = NULL;
 434
 435         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 436         if (!db_data.dptr) {
 437                 return -1; /* Error - missing entry ! */
 438         }
 439
 440         ld = (struct locking_data *)db_data.dptr;
 441         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 442         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 443
 444         if (orig_num_share_modes == 1) {
 445                 /* Only one entry - better be ours... */
 446                 if (!share_mode_entry_equal(del_entry, shares)) {
 447                         /* Error ! We can't delete someone else's entry ! */
 448                         free(db_data.dptr);
 449                         return -1;
 450                 }
 451                 /* It's ours - just remove the entire record. */
 452                 free(db_data.dptr);
 453                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 454         }
 455
 456         /* More than one - allocate a new record minus the one we'll delete. */
 457         new_data_p = (uint8 *)malloc(
 458                 db_data.dsize - sizeof(struct share_mode_entry));
 459         if (!new_data_p) {
 460                 free(db_data.dptr);
 461                 return -1;
 462         }
 463
 464         /* Copy the header. */
 465         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data));
 466
 467         num_share_modes = 0;
 468         for (i = 0; i < orig_num_share_modes; i++) {
 469                 struct share_mode_entry *share = &shares[i];
 470                 struct server_id pid = share->pid;
 471
 472                 /* Check this process really exists. */
 473                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 474                         continue; /* No longer exists. */
 475                 }
 476
 477                 if (share_mode_entry_equal(del_entry, share)) {
 478                         continue; /* This is our delete taget. */
 479                 }
 480
 481                 memcpy(new_data_p + sizeof(struct locking_data) +
 482                                 (num_share_modes * sizeof(struct share_mode_entry)),
 483                         share, sizeof(struct share_mode_entry) );
 484
 485                 num_share_modes++;
 486         }
 487
 488         if (num_share_modes == 0) {
 489                 /* None left after pruning. Delete record. */
 490                 free(db_data.dptr);
 491                 free(new_data_p);
 492                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 493         }
 494
 495         /* Copy any delete tokens plus the terminating filenames. */
 496         remaining_ptr = db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry));
 497         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 498
 499         memcpy(new_data_p + sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)),
 500                 remaining_ptr,
 501                 remaining_size);
 502
 503         free(db_data.dptr);
 504
 505         db_data.dptr = new_data_p;
 506
 507         /* Re-save smaller record. */
 508         ld = (struct locking_data *)db_data.dptr;
 509         ld->u.s.num_share_mode_entries = num_share_modes;
 510
 511         db_data.dsize = sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)) + remaining_size;
 512
 513         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 514                 free(db_data.dptr);
 515                 return -1;
 516         }
 517         free(db_data.dptr);
 518         return 0;
 519 }
 520
 521 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 522                                 uint64_t dev,
 523                                 uint64_t ino,
 524                                 uint64_t extid,
 525                                 const struct smb_share_mode_entry *set_entry,
 526                                 const struct smb_share_mode_entry *new_entry)
 527 {
 528         TDB_DATA db_data;
 529         struct locking_key lk;
 530         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 531         int num_share_modes = 0;
 532         struct locking_data *ld = NULL; /* internal samba db state. */
 533         struct share_mode_entry *shares = NULL;
 534         size_t i;
 535         int found_entry = 0;
 536
 537         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 538         if (!db_data.dptr) {
 539                 return -1; /* Error - missing entry ! */
 540         }
 541
 542         ld = (struct locking_data *)db_data.dptr;
 543         num_share_modes = ld->u.s.num_share_mode_entries;
 544         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 545
 546         for (i = 0; i < num_share_modes; i++) {
 547                 struct share_mode_entry *share = &shares[i];
 548                 struct server_id pid = share->pid;
 549
 550                 /* Check this process really exists. */
 551                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 552                         continue; /* No longer exists. */
 553                 }
 554
 555                 if (share_mode_entry_equal(set_entry, share)) {
 556                         create_share_mode_entry(share, new_entry, share->name_hash);
 557                         found_entry = 1;
 558                         break;
 559                 }
 560         }
 561
 562         if (!found_entry) {
 563                 free(db_data.dptr);
 564                 return -1;
 565         }
 566
 567         /* Save modified data. */
 568         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 569                 free(db_data.dptr);
 570                 return -1;
 571         }
 572         free(db_data.dptr);
 573         return 0;
 574 }