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 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         out->uid = (uint32)geteuid();
 153 }
 154
 155 /*
 156  * Return the current share mode list for an open file.
 157  * This uses similar (but simplified) logic to locking/locking.c
 158  */
 159
 160 int smb_get_share_mode_entries(struct smbdb_ctx *db_ctx,
 161                                 uint64_t dev,
 162                                 uint64_t ino,
 163                                 struct smb_share_mode_entry **pp_list,
 164                                 unsigned char *p_delete_on_close)
 165 {
 166         TDB_DATA db_data;
 167         struct smb_share_mode_entry *list = NULL;
 168         int num_share_modes = 0;
 169         struct locking_data *ld = NULL; /* internal samba db state. */
 170         struct share_mode_entry *shares = NULL;
 171         size_t i;
 172         int list_num;
 173
 174         *pp_list = NULL;
 175         *p_delete_on_close = 0;
 176
 177         db_data = tdb_fetch(db_ctx->smb_tdb, get_locking_key(dev, ino));
 178         if (!db_data.dptr) {
 179                 return 0;
 180         }
 181
 182         ld = (struct locking_data *)db_data.dptr;
 183         num_share_modes = ld->u.s.num_share_mode_entries;
 184
 185         if (!num_share_modes) {
 186                 free(db_data.dptr);
 187                 return 0;
 188         }
 189
 190         list = (struct smb_share_mode_entry *)malloc(sizeof(struct smb_share_mode_entry)*num_share_modes);
 191         if (!list) {
 192                 free(db_data.dptr);
 193                 return -1;
 194         }
 195
 196         memset(list, '\0', num_share_modes * sizeof(struct smb_share_mode_entry));
 197
 198         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct share_mode_entry));
 199
 200         list_num = 0;
 201         for (i = 0; i < num_share_modes; i++) {
 202                 struct share_mode_entry *share = &shares[i];
 203                 struct smb_share_mode_entry *sme = &list[list_num];
 204                 struct process_id pid = share->pid;
 205
 206                 /* Check this process really exists. */
 207                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 208                         continue; /* No longer exists. */
 209                 }
 210
 211                 /* Ignore deferred open entries. */
 212                 if (share->op_type == DEFERRED_OPEN_ENTRY) {
 213                         continue;
 214                 }
 215
 216                 /* Copy into the external list. */
 217                 sme->dev = (uint64_t)share->dev;
 218                 sme->ino = (uint64_t)share->inode;
 219                 sme->share_access = (uint32_t)share->share_access;
 220                 sme->access_mask = (uint32_t)share->access_mask;
 221                 sme->open_time.tv_sec = share->time.tv_sec;
 222                 sme->open_time.tv_usec = share->time.tv_usec;
 223                 sme->file_id = (uint32_t)share->share_file_id;
 224                 sme->pid = share->pid;
 225                 list_num++;
 226         }
 227
 228         if (list_num == 0) {
 229                 free(db_data.dptr);
 230                 free(list);
 231                 return 0;
 232         }
 233
 234         *p_delete_on_close = ld->u.s.delete_on_close;
 235         *pp_list = list;
 236         free(db_data.dptr);
 237         return list_num;
 238 }
 239
 240 /*
 241  * Create an entry in the Samba share mode db.
 242  */
 243
 244 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx,
 245                                 uint64_t dev,
 246                                 uint64_t ino,
 247                                 const struct smb_share_mode_entry *new_entry,
 248                                 const char *sharepath, /* Must be absolute utf8 path. */
 249                                 const char *filename) /* Must be relative utf8 path. */
 250 {
 251         TDB_DATA db_data;
 252         TDB_DATA locking_key =  get_locking_key(dev, ino);
 253         int orig_num_share_modes = 0;
 254         struct locking_data *ld = NULL; /* internal samba db state. */
 255         struct share_mode_entry *shares = NULL;
 256         char *new_data_p = NULL;
 257         size_t new_data_size = 0;
 258
 259         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 260         if (!db_data.dptr) {
 261                 /* We must create the entry. */
 262                 db_data.dptr = (char *)malloc(
 263                         (2*sizeof(struct share_mode_entry)) +
 264                         strlen(sharepath) + 1 +
 265                         strlen(filename) + 1);
 266                 if (!db_data.dptr) {
 267                         return -1;
 268                 }
 269                 ld = (struct locking_data *)db_data.dptr;
 270                 memset(ld, '\0', sizeof(struct locking_data));
 271                 ld->u.s.num_share_mode_entries = 1;
 272                 ld->u.s.delete_on_close = 0;
 273                 ld->u.s.initial_delete_on_close = 0;
 274                 ld->u.s.delete_token_size = 0;
 275                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct share_mode_entry));
 276                 create_share_mode_entry(shares, new_entry);
 277
 278                 memcpy(db_data.dptr + 2*sizeof(struct share_mode_entry),
 279                         sharepath,
 280                         strlen(sharepath) + 1);
 281                 memcpy(db_data.dptr + 2*sizeof(struct share_mode_entry) +
 282                         strlen(sharepath) + 1,
 283                         filename,
 284                         strlen(filename) + 1);
 285
 286                 db_data.dsize = 2*sizeof(struct share_mode_entry) +
 287                                         strlen(sharepath) + 1 +
 288                                         strlen(filename) + 1;
 289                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) == -1) {
 290                         free(db_data.dptr);
 291                         return -1;
 292                 }
 293                 free(db_data.dptr);
 294                 return 0;
 295         }
 296
 297         /* Entry exists, we must add a new entry. */
 298         new_data_p = (char *)malloc(
 299                 db_data.dsize + sizeof(struct share_mode_entry));
 300         if (!new_data_p) {
 301                 free(db_data.dptr);
 302                 return -1;
 303         }
 304
 305         ld = (struct locking_data *)db_data.dptr;
 306         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 307
 308         /* Copy the original data. */
 309         memcpy(new_data_p, db_data.dptr, (orig_num_share_modes+1)*sizeof(struct share_mode_entry));
 310
 311         /* Add in the new share mode */
 312         shares = (struct share_mode_entry *)(new_data_p +
 313                         ((orig_num_share_modes+1)*sizeof(struct share_mode_entry)));
 314
 315         create_share_mode_entry(shares, new_entry);
 316
 317         ld = (struct locking_data *)new_data_p;
 318         ld->u.s.num_share_mode_entries++;
 319
 320         /* Append the original delete_token and filenames. */
 321         memcpy(new_data_p + ((ld->u.s.num_share_mode_entries+1)*sizeof(struct share_mode_entry)),
 322                 db_data.dptr + ((orig_num_share_modes+1)*sizeof(struct share_mode_entry)),
 323                 db_data.dsize - ((orig_num_share_modes+1) * sizeof(struct share_mode_entry)));
 324
 325         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 326
 327         free(db_data.dptr);
 328
 329         db_data.dptr = new_data_p;
 330         db_data.dsize = new_data_size;
 331
 332         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 333                 free(db_data.dptr);
 334                 return -1;
 335         }
 336         free(db_data.dptr);
 337         return 0;
 338 }
 339
 340 /*
 341  * Create an entry in the Samba share mode db. Original interface - doesn't
 342  * Distinguish between share path and filename. Fudge this by using a
 343  * sharepath of / and a relative filename of (filename+1).
 344  */
 345
 346 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 347                                 uint64_t dev,
 348                                 uint64_t ino,
 349                                 const struct smb_share_mode_entry *new_entry,
 350                                 const char *filename) /* Must be absolute utf8 path. */
 351 {
 352         if (*filename != '/') {
 353                 abort();
 354         }
 355         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, new_entry,
 356                                                 "/", &filename[1]);
 357 }
 358
 359 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 360                                 uint64_t dev,
 361                                 uint64_t ino,
 362                                 const struct smb_share_mode_entry *del_entry)
 363 {
 364         TDB_DATA db_data;
 365         TDB_DATA locking_key =  get_locking_key(dev, ino);
 366         int orig_num_share_modes = 0;
 367         struct locking_data *ld = NULL; /* internal samba db state. */
 368         struct share_mode_entry *shares = NULL;
 369         char *new_data_p = NULL;
 370         size_t remaining_size = 0;
 371         size_t i, num_share_modes;
 372         const char *remaining_ptr = NULL;
 373
 374         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 375         if (!db_data.dptr) {
 376                 return -1; /* Error - missing entry ! */
 377         }
 378
 379         ld = (struct locking_data *)db_data.dptr;
 380         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 381         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct share_mode_entry));
 382
 383         if (orig_num_share_modes == 1) {
 384                 /* Only one entry - better be ours... */
 385                 if (!share_mode_entry_equal(del_entry, shares)) {
 386                         /* Error ! We can't delete someone else's entry ! */
 387                         free(db_data.dptr);
 388                         return -1;
 389                 }
 390                 /* It's ours - just remove the entire record. */
 391                 free(db_data.dptr);
 392                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 393         }
 394
 395         /* More than one - allocate a new record minus the one we'll delete. */
 396         new_data_p = (char *)malloc(
 397                 db_data.dsize - sizeof(struct share_mode_entry));
 398         if (!new_data_p) {
 399                 free(db_data.dptr);
 400                 return -1;
 401         }
 402
 403         /* Copy the header. */
 404         memcpy(new_data_p, db_data.dptr, sizeof(struct share_mode_entry));
 405
 406         num_share_modes = 0;
 407         for (i = 0; i < orig_num_share_modes; i++) {
 408                 struct share_mode_entry *share = &shares[i];
 409                 struct process_id pid = share->pid;
 410
 411                 /* Check this process really exists. */
 412                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 413                         continue; /* No longer exists. */
 414                 }
 415
 416                 if (share_mode_entry_equal(del_entry, share)) {
 417                         continue; /* This is our delete taget. */
 418                 }
 419
 420                 memcpy(new_data_p + ((num_share_modes+1)*sizeof(struct share_mode_entry)),
 421                         share, sizeof(struct share_mode_entry) );
 422
 423                 num_share_modes++;
 424         }
 425
 426         if (num_share_modes == 0) {
 427                 /* None left after pruning. Delete record. */
 428                 free(db_data.dptr);
 429                 free(new_data_p);
 430                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 431         }
 432
 433         /* Copy any delete token plus the terminating filenames. */
 434         remaining_ptr = db_data.dptr + ((orig_num_share_modes+1) * sizeof(struct share_mode_entry));
 435         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 436
 437         memcpy(new_data_p + ((num_share_modes+1)*sizeof(struct share_mode_entry)),
 438                 remaining_ptr,
 439                 remaining_size);
 440
 441         free(db_data.dptr);
 442
 443         db_data.dptr = new_data_p;
 444
 445         /* Re-save smaller record. */
 446         ld = (struct locking_data *)db_data.dptr;
 447         ld->u.s.num_share_mode_entries = num_share_modes;
 448
 449         db_data.dsize = ((num_share_modes+1)*sizeof(struct share_mode_entry)) + remaining_size;
 450
 451         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 452                 free(db_data.dptr);
 453                 return -1;
 454         }
 455         free(db_data.dptr);
 456         return 0;
 457 }
 458
 459 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 460                                 uint64_t dev,
 461                                 uint64_t ino,
 462                                 const struct smb_share_mode_entry *set_entry,
 463                                 const struct smb_share_mode_entry *new_entry)
 464 {
 465         TDB_DATA db_data;
 466         TDB_DATA locking_key =  get_locking_key(dev, ino);
 467         int num_share_modes = 0;
 468         struct locking_data *ld = NULL; /* internal samba db state. */
 469         struct share_mode_entry *shares = NULL;
 470         size_t i;
 471         int found_entry = 0;
 472
 473         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 474         if (!db_data.dptr) {
 475                 return -1; /* Error - missing entry ! */
 476         }
 477
 478         ld = (struct locking_data *)db_data.dptr;
 479         num_share_modes = ld->u.s.num_share_mode_entries;
 480         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct share_mode_entry));
 481
 482         for (i = 0; i < num_share_modes; i++) {
 483                 struct share_mode_entry *share = &shares[i];
 484                 struct process_id pid = share->pid;
 485
 486                 /* Check this process really exists. */
 487                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 488                         continue; /* No longer exists. */
 489                 }
 490
 491                 if (share_mode_entry_equal(set_entry, share)) {
 492                         create_share_mode_entry(share, new_entry);
 493                         found_entry = 1;
 494                         break;
 495                 }
 496         }
 497
 498         if (!found_entry) {
 499                 free(db_data.dptr);
 500                 return -1;
 501         }
 502
 503         /* Save modified data. */
 504         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 505                 free(db_data.dptr);
 506                 return -1;
 507         }
 508         free(db_data.dptr);
 509         return 0;
 510 }