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