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, write to the Free Software
  25    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  26 */
  27
  28 #include "includes.h"
  29 #include "smb_share_modes.h"
  30
  31 /* Database context handle. */
  32 struct smbdb_ctx {
  33         TDB_CONTEXT *smb_tdb;
  34 };
  35
  36 /* Remove the paranoid malloc checker. */
  37 #ifdef malloc
  38 #undef malloc
  39 #endif
  40
  41 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx, uint64_t dev,
  42                                 uint64_t ino, 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,
  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 };
  88
  89 int smb_share_mode_db_close(struct smbdb_ctx *db_ctx)
  90 {
  91         int ret = tdb_close(db_ctx->smb_tdb);
  92         free(db_ctx);
  93         return ret;
  94 }
  95
  96 static TDB_DATA get_locking_key(uint64_t dev, uint64_t ino)
  97 {
  98         static struct locking_key lk;
  99         TDB_DATA ld;
 100
 101         memset(&lk, '\0', sizeof(struct locking_key));
 102         lk.dev = (SMB_DEV_T)dev;
 103         lk.inode = (SMB_INO_T)ino;
 104         ld.dptr = (uint8 *)&lk;
 105         ld.dsize = sizeof(lk);
 106         return ld;
 107 }
 108
 109 /*
 110  * lock/unlock entry in sharemode database.
 111  */
 112
 113 int smb_lock_share_mode_entry(struct smbdb_ctx *db_ctx,
 114                                 uint64_t dev,
 115                                 uint64_t ino)
 116 {
 117         return tdb_chainlock(db_ctx->smb_tdb, get_locking_key(dev, ino));
 118 }
 119
 120 int smb_unlock_share_mode_entry(struct smbdb_ctx *db_ctx,
 121                                 uint64_t dev,
 122                                 uint64_t ino)
 123 {
 124         return tdb_chainunlock(db_ctx->smb_tdb, get_locking_key(dev, ino));
 125 }
 126
 127 /*
 128  * Check if an external smb_share_mode_entry and an internal share_mode entry match.
 129  */
 130
 131 static int share_mode_entry_equal(const struct smb_share_mode_entry *e_entry,
 132                                 const struct share_mode_entry *entry)
 133 {
 134         return (sharemodes_procid_equal(&e_entry->pid, &entry->pid) &&
 135                 e_entry->file_id == (uint32_t)entry->share_file_id &&
 136                 e_entry->open_time.tv_sec == entry->time.tv_sec &&
 137                 e_entry->open_time.tv_usec == entry->time.tv_usec &&
 138                 e_entry->share_access == (uint32_t)entry->share_access &&
 139                 e_entry->access_mask == (uint32_t)entry->access_mask &&
 140                 e_entry->dev == entry->id.devid &&
 141                 e_entry->ino == entry->id.inode);
 142 }
 143
 144 /*
 145  * Create an internal Samba share_mode entry from an external smb_share_mode_entry.
 146  */
 147
 148 static void create_share_mode_entry(struct share_mode_entry *out,
 149                                 const struct smb_share_mode_entry *in)
 150 {
 151         memset(out, '\0', sizeof(struct share_mode_entry));
 152
 153         out->pid = in->pid;
 154         out->share_file_id = (unsigned long)in->file_id;
 155         out->time.tv_sec = in->open_time.tv_sec;
 156         out->time.tv_usec = in->open_time.tv_usec;
 157         out->share_access = in->share_access;
 158         out->access_mask = in->access_mask;
 159         out->id.devid = in->dev;
 160         out->id.inode = in->ino;
 161         out->uid = (uint32)geteuid();
 162         out->flags = 0;
 163 }
 164
 165 /*
 166  * Return the current share mode list for an open file.
 167  * This uses similar (but simplified) logic to locking/locking.c
 168  */
 169
 170 int smb_get_share_mode_entries(struct smbdb_ctx *db_ctx,
 171                                 uint64_t dev,
 172                                 uint64_t ino,
 173                                 struct smb_share_mode_entry **pp_list,
 174                                 unsigned char *p_delete_on_close)
 175 {
 176         TDB_DATA db_data;
 177         struct smb_share_mode_entry *list = NULL;
 178         int num_share_modes = 0;
 179         struct locking_data *ld = NULL; /* internal samba db state. */
 180         struct share_mode_entry *shares = NULL;
 181         size_t i;
 182         int list_num;
 183
 184         *pp_list = NULL;
 185         *p_delete_on_close = 0;
 186
 187         db_data = tdb_fetch(db_ctx->smb_tdb, get_locking_key(dev, ino));
 188         if (!db_data.dptr) {
 189                 return 0;
 190         }
 191
 192         ld = (struct locking_data *)db_data.dptr;
 193         num_share_modes = ld->u.s.num_share_mode_entries;
 194
 195         if (!num_share_modes) {
 196                 free(db_data.dptr);
 197                 return 0;
 198         }
 199
 200         list = (struct smb_share_mode_entry *)malloc(sizeof(struct smb_share_mode_entry)*num_share_modes);
 201         if (!list) {
 202                 free(db_data.dptr);
 203                 return -1;
 204         }
 205
 206         memset(list, '\0', num_share_modes * sizeof(struct smb_share_mode_entry));
 207
 208         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 209
 210         list_num = 0;
 211         for (i = 0; i < num_share_modes; i++) {
 212                 struct share_mode_entry *share = &shares[i];
 213                 struct smb_share_mode_entry *sme = &list[list_num];
 214                 struct server_id pid = share->pid;
 215
 216                 /* Check this process really exists. */
 217                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 218                         continue; /* No longer exists. */
 219                 }
 220
 221                 /* Ignore deferred open entries. */
 222                 if (share->op_type == DEFERRED_OPEN_ENTRY) {
 223                         continue;
 224                 }
 225
 226                 /* Copy into the external list. */
 227                 sme->dev = share->id.devid;
 228                 sme->ino = share->id.inode;
 229                 sme->share_access = (uint32_t)share->share_access;
 230                 sme->access_mask = (uint32_t)share->access_mask;
 231                 sme->open_time.tv_sec = share->time.tv_sec;
 232                 sme->open_time.tv_usec = share->time.tv_usec;
 233                 sme->file_id = (uint32_t)share->share_file_id;
 234                 sme->pid = share->pid;
 235                 list_num++;
 236         }
 237
 238         if (list_num == 0) {
 239                 free(db_data.dptr);
 240                 free(list);
 241                 return 0;
 242         }
 243
 244         *p_delete_on_close = ld->u.s.delete_on_close;
 245         *pp_list = list;
 246         free(db_data.dptr);
 247         return list_num;
 248 }
 249
 250 /*
 251  * Create an entry in the Samba share mode db.
 252  */
 253
 254 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx,
 255                                 uint64_t dev,
 256                                 uint64_t ino,
 257                                 const struct smb_share_mode_entry *new_entry,
 258                                 const char *sharepath, /* Must be absolute utf8 path. */
 259                                 const char *filename) /* Must be relative utf8 path. */
 260 {
 261         TDB_DATA db_data;
 262         TDB_DATA locking_key =  get_locking_key(dev, ino);
 263         int orig_num_share_modes = 0;
 264         struct locking_data *ld = NULL; /* internal samba db state. */
 265         struct share_mode_entry *shares = NULL;
 266         uint8 *new_data_p = NULL;
 267         size_t new_data_size = 0;
 268
 269         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 270         if (!db_data.dptr) {
 271                 /* We must create the entry. */
 272                 db_data.dptr = (uint8 *)malloc(
 273                         sizeof(struct locking_data) +
 274                         sizeof(struct share_mode_entry) +
 275                         strlen(sharepath) + 1 +
 276                         strlen(filename) + 1);
 277                 if (!db_data.dptr) {
 278                         return -1;
 279                 }
 280                 ld = (struct locking_data *)db_data.dptr;
 281                 memset(ld, '\0', sizeof(struct locking_data));
 282                 ld->u.s.num_share_mode_entries = 1;
 283                 ld->u.s.delete_on_close = 0;
 284                 ld->u.s.delete_token_size = 0;
 285                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 286                 create_share_mode_entry(shares, new_entry);
 287
 288                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry),
 289                         sharepath,
 290                         strlen(sharepath) + 1);
 291                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 292                         strlen(sharepath) + 1,
 293                         filename,
 294                         strlen(filename) + 1);
 295
 296                 db_data.dsize = sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 297                                         strlen(sharepath) + 1 +
 298                                         strlen(filename) + 1;
 299                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) == -1) {
 300                         free(db_data.dptr);
 301                         return -1;
 302                 }
 303                 free(db_data.dptr);
 304                 return 0;
 305         }
 306
 307         /* Entry exists, we must add a new entry. */
 308         new_data_p = (uint8 *)malloc(
 309                 db_data.dsize + sizeof(struct share_mode_entry));
 310         if (!new_data_p) {
 311                 free(db_data.dptr);
 312                 return -1;
 313         }
 314
 315         ld = (struct locking_data *)db_data.dptr;
 316         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 317
 318         /* Copy the original data. */
 319         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)));
 320
 321         /* Add in the new share mode */
 322         shares = (struct share_mode_entry *)(new_data_p + sizeof(struct locking_data) +
 323                         (orig_num_share_modes * sizeof(struct share_mode_entry)));
 324
 325         create_share_mode_entry(shares, new_entry);
 326
 327         ld = (struct locking_data *)new_data_p;
 328         ld->u.s.num_share_mode_entries++;
 329
 330         /* Append the original delete_token and filenames. */
 331         memcpy(new_data_p + sizeof(struct locking_data) + (ld->u.s.num_share_mode_entries * sizeof(struct share_mode_entry)),
 332                 db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)),
 333                 db_data.dsize - sizeof(struct locking_data) - (orig_num_share_modes * sizeof(struct share_mode_entry)));
 334
 335         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 336
 337         free(db_data.dptr);
 338
 339         db_data.dptr = new_data_p;
 340         db_data.dsize = new_data_size;
 341
 342         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 343                 free(db_data.dptr);
 344                 return -1;
 345         }
 346         free(db_data.dptr);
 347         return 0;
 348 }
 349
 350 /*
 351  * Create an entry in the Samba share mode db. Original interface - doesn't
 352  * Distinguish between share path and filename. Fudge this by using a
 353  * sharepath of / and a relative filename of (filename+1).
 354  */
 355
 356 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 357                                 uint64_t dev,
 358                                 uint64_t ino,
 359                                 const struct smb_share_mode_entry *new_entry,
 360                                 const char *filename) /* Must be absolute utf8 path. */
 361 {
 362         if (*filename != '/') {
 363                 abort();
 364         }
 365         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, new_entry,
 366                                                 "/", &filename[1]);
 367 }
 368
 369 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 370                                 uint64_t dev,
 371                                 uint64_t ino,
 372                                 const struct smb_share_mode_entry *del_entry)
 373 {
 374         TDB_DATA db_data;
 375         TDB_DATA locking_key =  get_locking_key(dev, ino);
 376         int orig_num_share_modes = 0;
 377         struct locking_data *ld = NULL; /* internal samba db state. */
 378         struct share_mode_entry *shares = NULL;
 379         uint8 *new_data_p = NULL;
 380         size_t remaining_size = 0;
 381         size_t i, num_share_modes;
 382         const uint8 *remaining_ptr = NULL;
 383
 384         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 385         if (!db_data.dptr) {
 386                 return -1; /* Error - missing entry ! */
 387         }
 388
 389         ld = (struct locking_data *)db_data.dptr;
 390         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 391         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 392
 393         if (orig_num_share_modes == 1) {
 394                 /* Only one entry - better be ours... */
 395                 if (!share_mode_entry_equal(del_entry, shares)) {
 396                         /* Error ! We can't delete someone else's entry ! */
 397                         free(db_data.dptr);
 398                         return -1;
 399                 }
 400                 /* It's ours - just remove the entire record. */
 401                 free(db_data.dptr);
 402                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 403         }
 404
 405         /* More than one - allocate a new record minus the one we'll delete. */
 406         new_data_p = (uint8 *)malloc(
 407                 db_data.dsize - sizeof(struct share_mode_entry));
 408         if (!new_data_p) {
 409                 free(db_data.dptr);
 410                 return -1;
 411         }
 412
 413         /* Copy the header. */
 414         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data));
 415
 416         num_share_modes = 0;
 417         for (i = 0; i < orig_num_share_modes; i++) {
 418                 struct share_mode_entry *share = &shares[i];
 419                 struct server_id pid = share->pid;
 420
 421                 /* Check this process really exists. */
 422                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 423                         continue; /* No longer exists. */
 424                 }
 425
 426                 if (share_mode_entry_equal(del_entry, share)) {
 427                         continue; /* This is our delete taget. */
 428                 }
 429
 430                 memcpy(new_data_p + sizeof(struct locking_data) +
 431                                 (num_share_modes * sizeof(struct share_mode_entry)),
 432                         share, sizeof(struct share_mode_entry) );
 433
 434                 num_share_modes++;
 435         }
 436
 437         if (num_share_modes == 0) {
 438                 /* None left after pruning. Delete record. */
 439                 free(db_data.dptr);
 440                 free(new_data_p);
 441                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 442         }
 443
 444         /* Copy any delete token plus the terminating filenames. */
 445         remaining_ptr = db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry));
 446         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 447
 448         memcpy(new_data_p + sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)),
 449                 remaining_ptr,
 450                 remaining_size);
 451
 452         free(db_data.dptr);
 453
 454         db_data.dptr = new_data_p;
 455
 456         /* Re-save smaller record. */
 457         ld = (struct locking_data *)db_data.dptr;
 458         ld->u.s.num_share_mode_entries = num_share_modes;
 459
 460         db_data.dsize = sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)) + remaining_size;
 461
 462         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 463                 free(db_data.dptr);
 464                 return -1;
 465         }
 466         free(db_data.dptr);
 467         return 0;
 468 }
 469
 470 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 471                                 uint64_t dev,
 472                                 uint64_t ino,
 473                                 const struct smb_share_mode_entry *set_entry,
 474                                 const struct smb_share_mode_entry *new_entry)
 475 {
 476         TDB_DATA db_data;
 477         TDB_DATA locking_key =  get_locking_key(dev, ino);
 478         int num_share_modes = 0;
 479         struct locking_data *ld = NULL; /* internal samba db state. */
 480         struct share_mode_entry *shares = NULL;
 481         size_t i;
 482         int found_entry = 0;
 483
 484         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 485         if (!db_data.dptr) {
 486                 return -1; /* Error - missing entry ! */
 487         }
 488
 489         ld = (struct locking_data *)db_data.dptr;
 490         num_share_modes = ld->u.s.num_share_mode_entries;
 491         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 492
 493         for (i = 0; i < num_share_modes; i++) {
 494                 struct share_mode_entry *share = &shares[i];
 495                 struct server_id pid = share->pid;
 496
 497                 /* Check this process really exists. */
 498                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 499                         continue; /* No longer exists. */
 500                 }
 501
 502                 if (share_mode_entry_equal(set_entry, share)) {
 503                         create_share_mode_entry(share, new_entry);
 504                         found_entry = 1;
 505                         break;
 506                 }
 507         }
 508
 509         if (!found_entry) {
 510                 free(db_data.dptr);
 511                 return -1;
 512         }
 513
 514         /* Save modified data. */
 515         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 516                 free(db_data.dptr);
 517                 return -1;
 518         }
 519         free(db_data.dptr);
 520         return 0;
 521 }