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 "system/filesys.h"
  29 #include "smb_share_modes.h"
  30 #include <tdb.h>
  31
  32 /* Database context handle. */
  33 struct smbdb_ctx {
  34         TDB_CONTEXT *smb_tdb;
  35 };
  36
  37 /* Remove the paranoid malloc checker. */
  38 #ifdef malloc
  39 #undef malloc
  40 #endif
  41
  42 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx, uint64_t dev,
  43                                 uint64_t ino, uint64_t extid,
  44                                 const struct smb_share_mode_entry *new_entry,
  45                                 const char *sharepath, const char *filename);
  46
  47 static bool sharemodes_procid_equal(const struct server_id *p1, const struct server_id *p2)
  48 {
  49         return (p1->pid == p2->pid);
  50 }
  51
  52 static pid_t sharemodes_procid_to_pid(const struct server_id *proc)
  53 {
  54         return proc->pid;
  55 }
  56
  57 /*
  58  * open/close sharemode database.
  59  */
  60
  61 struct smbdb_ctx *smb_share_mode_db_open(const char *db_path)
  62 {
  63         struct smbdb_ctx *smb_db = (struct smbdb_ctx *)malloc(sizeof(struct smbdb_ctx));
  64
  65         if (!smb_db) {
  66                 return NULL;
  67         }
  68
  69         memset(smb_db, '\0', sizeof(struct smbdb_ctx));
  70
  71         smb_db->smb_tdb = tdb_open(db_path,
  72                                 0, TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH,
  73                                 O_RDWR|O_CREAT,
  74                                 0644);
  75
  76         if (!smb_db->smb_tdb) {
  77                 free(smb_db);
  78                 return NULL;
  79         }
  80
  81         /* Should check that this is the correct version.... */
  82         return smb_db;
  83 }
  84
  85 /* key and data records in the tdb locking database */
  86 struct locking_key {
  87         SMB_DEV_T dev;
  88         SMB_INO_T inode;
  89         uint64_t extid;
  90 };
  91
  92 int smb_share_mode_db_close(struct smbdb_ctx *db_ctx)
  93 {
  94         int ret = tdb_close(db_ctx->smb_tdb);
  95         free(db_ctx);
  96         return ret;
  97 }
  98
  99 static TDB_DATA get_locking_key(struct locking_key *lk, uint64_t dev,
 100                                 uint64_t ino, uint64_t extid)
 101 {
 102         TDB_DATA ld;
 103
 104         memset(lk, '\0', sizeof(*lk));
 105         lk->dev = (SMB_DEV_T)dev;
 106         lk->inode = (SMB_INO_T)ino;
 107         lk->extid = extid;
 108         ld.dptr = (uint8 *)lk;
 109         ld.dsize = sizeof(*lk);
 110         return ld;
 111 }
 112
 113 /*
 114  * lock/unlock entry in sharemode database.
 115  */
 116
 117 int smb_lock_share_mode_entry(struct smbdb_ctx *db_ctx,
 118                                 uint64_t dev,
 119                                 uint64_t ino,
 120                                 uint64_t extid)
 121 {
 122         struct locking_key lk;
 123         return tdb_chainlock(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino,
 124                                                               extid));
 125 }
 126
 127 int smb_unlock_share_mode_entry(struct smbdb_ctx *db_ctx,
 128                                 uint64_t dev,
 129                                 uint64_t ino,
 130                                 uint64_t extid)
 131 {
 132         struct locking_key lk;
 133         return tdb_chainunlock(db_ctx->smb_tdb,
 134                                get_locking_key(&lk, dev, ino, extid));
 135 }
 136
 137 /*
 138  * Check if an external smb_share_mode_entry and an internal share_mode entry match.
 139  */
 140
 141 static int share_mode_entry_equal(const struct smb_share_mode_entry *e_entry,
 142                                 const struct share_mode_entry *entry)
 143 {
 144         return (sharemodes_procid_equal(&e_entry->pid, &entry->pid) &&
 145                 e_entry->file_id == (uint32_t)entry->share_file_id &&
 146                 e_entry->open_time.tv_sec == entry->time.tv_sec &&
 147                 e_entry->open_time.tv_usec == entry->time.tv_usec &&
 148                 e_entry->share_access == (uint32_t)entry->share_access &&
 149                 e_entry->access_mask == (uint32_t)entry->access_mask &&
 150                 e_entry->dev == entry->id.devid &&
 151                 e_entry->ino == entry->id.inode &&
 152                 e_entry->extid == entry->id.extid);
 153 }
 154
 155 /*
 156  * Create an internal Samba share_mode entry from an external smb_share_mode_entry.
 157  */
 158
 159 static void create_share_mode_entry(struct share_mode_entry *out,
 160                                 const struct smb_share_mode_entry *in,
 161                                 uint32_t name_hash)
 162 {
 163         memset(out, '\0', sizeof(struct share_mode_entry));
 164
 165         out->pid = in->pid;
 166         out->share_file_id = (unsigned long)in->file_id;
 167         out->time.tv_sec = in->open_time.tv_sec;
 168         out->time.tv_usec = in->open_time.tv_usec;
 169         out->share_access = in->share_access;
 170         out->access_mask = in->access_mask;
 171         out->id.devid = in->dev;
 172         out->id.inode = in->ino;
 173         out->id.extid = in->extid;
 174         out->uid = (uint32)geteuid();
 175         out->flags = 0;
 176         out->name_hash = name_hash;
 177 }
 178
 179 /*
 180  * Return the current share mode list for an open file.
 181  * This uses similar (but simplified) logic to locking/locking.c
 182  */
 183
 184 int smb_get_share_mode_entries(struct smbdb_ctx *db_ctx,
 185                                 uint64_t dev,
 186                                 uint64_t ino,
 187                                 uint64_t extid,
 188                                 struct smb_share_mode_entry **pp_list,
 189                                 unsigned char *p_delete_on_close)
 190 {
 191         struct locking_key lk;
 192         TDB_DATA db_data;
 193         struct smb_share_mode_entry *list = NULL;
 194         int num_share_modes = 0;
 195         struct locking_data *ld = NULL; /* internal samba db state. */
 196         struct share_mode_entry *shares = NULL;
 197         size_t i;
 198         int list_num;
 199
 200         *pp_list = NULL;
 201         *p_delete_on_close = 0;
 202
 203         db_data = tdb_fetch(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino,
 204                                                              extid));
 205         if (!db_data.dptr) {
 206                 return 0;
 207         }
 208
 209         ld = (struct locking_data *)db_data.dptr;
 210         num_share_modes = ld->u.s.num_share_mode_entries;
 211
 212         if (!num_share_modes) {
 213                 free(db_data.dptr);
 214                 return 0;
 215         }
 216
 217         list = (struct smb_share_mode_entry *)malloc(sizeof(struct smb_share_mode_entry)*num_share_modes);
 218         if (!list) {
 219                 free(db_data.dptr);
 220                 return -1;
 221         }
 222
 223         memset(list, '\0', num_share_modes * sizeof(struct smb_share_mode_entry));
 224
 225         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 226
 227         list_num = 0;
 228         for (i = 0; i < num_share_modes; i++) {
 229                 struct share_mode_entry *share = &shares[i];
 230                 struct smb_share_mode_entry *sme = &list[list_num];
 231                 struct server_id pid = share->pid;
 232
 233                 /* Check this process really exists. */
 234                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 235                         continue; /* No longer exists. */
 236                 }
 237
 238                 /* Ignore deferred open entries. */
 239                 if (share->op_type == DEFERRED_OPEN_ENTRY) {
 240                         continue;
 241                 }
 242
 243                 /* Copy into the external list. */
 244                 sme->dev = share->id.devid;
 245                 sme->ino = share->id.inode;
 246                 sme->extid = share->id.extid;
 247                 sme->share_access = (uint32_t)share->share_access;
 248                 sme->access_mask = (uint32_t)share->access_mask;
 249                 sme->open_time.tv_sec = share->time.tv_sec;
 250                 sme->open_time.tv_usec = share->time.tv_usec;
 251                 sme->file_id = (uint32_t)share->share_file_id;
 252                 sme->pid = share->pid;
 253                 list_num++;
 254         }
 255
 256         if (list_num == 0) {
 257                 free(db_data.dptr);
 258                 free(list);
 259                 return 0;
 260         }
 261
 262         *p_delete_on_close = ld->u.s.num_delete_token_entries != 0;
 263         *pp_list = list;
 264         free(db_data.dptr);
 265         return list_num;
 266 }
 267
 268 static uint32_t smb_name_hash(const char *sharepath, const char *filename, int *err)
 269 {
 270         TDB_DATA key;
 271         char *fullpath = NULL;
 272         size_t sharepath_size = strlen(sharepath);
 273         size_t filename_size = strlen(filename);
 274         uint32_t name_hash;
 275
 276         *err = 0;
 277         fullpath = (char *)malloc(sharepath_size + filename_size + 2);
 278         if (fullpath == NULL) {
 279                 *err = 1;
 280                 return 0;
 281         }
 282         memcpy(fullpath, sharepath, sharepath_size);
 283         fullpath[sharepath_size] = '/';
 284         memcpy(&fullpath[sharepath_size + 1], filename, filename_size + 1);
 285
 286         key.dptr = (uint8_t *)fullpath;
 287         key.dsize = strlen(fullpath) + 1;
 288         name_hash = tdb_jenkins_hash(&key);
 289         free(fullpath);
 290         return name_hash;
 291 }
 292
 293 /*
 294  * Create an entry in the Samba share mode db.
 295  */
 296
 297 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx,
 298                                 uint64_t dev,
 299                                 uint64_t ino,
 300                                 uint64_t extid,
 301                                 const struct smb_share_mode_entry *new_entry,
 302                                 const char *sharepath, /* Must be absolute utf8 path. */
 303                                 const char *filename) /* Must be relative utf8 path. */
 304 {
 305         TDB_DATA db_data;
 306         struct locking_key lk;
 307         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 308         int orig_num_share_modes = 0;
 309         struct locking_data *ld = NULL; /* internal samba db state. */
 310         struct share_mode_entry *shares = NULL;
 311         uint8 *new_data_p = NULL;
 312         size_t new_data_size = 0;
 313         int err = 0;
 314         uint32_t name_hash = smb_name_hash(sharepath, filename, &err);
 315
 316         if (err) {
 317                 return -1;
 318         }
 319
 320         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 321         if (!db_data.dptr) {
 322                 /* We must create the entry. */
 323                 db_data.dptr = (uint8 *)malloc(
 324                         sizeof(struct locking_data) +
 325                         sizeof(struct share_mode_entry) +
 326                         strlen(sharepath) + 1 +
 327                         strlen(filename) + 1);
 328                 if (!db_data.dptr) {
 329                         return -1;
 330                 }
 331                 ld = (struct locking_data *)db_data.dptr;
 332                 memset(ld, '\0', sizeof(struct locking_data));
 333                 ld->u.s.num_share_mode_entries = 1;
 334                 ld->u.s.num_delete_token_entries = 0;
 335                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 336                 create_share_mode_entry(shares, new_entry, name_hash);
 337
 338                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry),
 339                         sharepath,
 340                         strlen(sharepath) + 1);
 341                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 342                         strlen(sharepath) + 1,
 343                         filename,
 344                         strlen(filename) + 1);
 345
 346                 db_data.dsize = sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 347                                         strlen(sharepath) + 1 +
 348                                         strlen(filename) + 1;
 349                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) == -1) {
 350                         free(db_data.dptr);
 351                         return -1;
 352                 }
 353                 free(db_data.dptr);
 354                 return 0;
 355         }
 356
 357         /* Entry exists, we must add a new entry. */
 358         new_data_p = (uint8 *)malloc(
 359                 db_data.dsize + sizeof(struct share_mode_entry));
 360         if (!new_data_p) {
 361                 free(db_data.dptr);
 362                 return -1;
 363         }
 364
 365         ld = (struct locking_data *)db_data.dptr;
 366         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 367
 368         /* Copy the original data. */
 369         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)));
 370
 371         /* Add in the new share mode */
 372         shares = (struct share_mode_entry *)(new_data_p + sizeof(struct locking_data) +
 373                         (orig_num_share_modes * sizeof(struct share_mode_entry)));
 374
 375         create_share_mode_entry(shares, new_entry, name_hash);
 376
 377         ld = (struct locking_data *)new_data_p;
 378         ld->u.s.num_share_mode_entries++;
 379
 380         /* Append the original delete_tokens and filenames. */
 381         memcpy(new_data_p + sizeof(struct locking_data) + (ld->u.s.num_share_mode_entries * sizeof(struct share_mode_entry)),
 382                 db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)),
 383                 db_data.dsize - sizeof(struct locking_data) - (orig_num_share_modes * sizeof(struct share_mode_entry)));
 384
 385         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 386
 387         free(db_data.dptr);
 388
 389         db_data.dptr = new_data_p;
 390         db_data.dsize = new_data_size;
 391
 392         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 393                 free(db_data.dptr);
 394                 return -1;
 395         }
 396         free(db_data.dptr);
 397         return 0;
 398 }
 399
 400 /*
 401  * Create an entry in the Samba share mode db. Original interface - doesn't
 402  * Distinguish between share path and filename. Fudge this by using a
 403  * sharepath of / and a relative filename of (filename+1).
 404  */
 405
 406 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 407                                 uint64_t dev,
 408                                 uint64_t ino,
 409                                 uint64_t extid,
 410                                 const struct smb_share_mode_entry *new_entry,
 411                                 const char *filename) /* Must be absolute utf8 path. */
 412 {
 413         if (*filename != '/') {
 414                 abort();
 415         }
 416         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, extid, new_entry,
 417                                                 "/", &filename[1]);
 418 }
 419
 420 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 421                                 uint64_t dev,
 422                                 uint64_t ino,
 423                                 uint64_t extid,
 424                                 const struct smb_share_mode_entry *del_entry)
 425 {
 426         TDB_DATA db_data;
 427         struct locking_key lk;
 428         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 429         int orig_num_share_modes = 0;
 430         struct locking_data *ld = NULL; /* internal samba db state. */
 431         struct share_mode_entry *shares = NULL;
 432         uint8 *new_data_p = NULL;
 433         size_t remaining_size = 0;
 434         size_t i, num_share_modes;
 435         const uint8 *remaining_ptr = NULL;
 436
 437         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 438         if (!db_data.dptr) {
 439                 return -1; /* Error - missing entry ! */
 440         }
 441
 442         ld = (struct locking_data *)db_data.dptr;
 443         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 444         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 445
 446         if (orig_num_share_modes == 1) {
 447                 /* Only one entry - better be ours... */
 448                 if (!share_mode_entry_equal(del_entry, shares)) {
 449                         /* Error ! We can't delete someone else's entry ! */
 450                         free(db_data.dptr);
 451                         return -1;
 452                 }
 453                 /* It's ours - just remove the entire record. */
 454                 free(db_data.dptr);
 455                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 456         }
 457
 458         /* More than one - allocate a new record minus the one we'll delete. */
 459         new_data_p = (uint8 *)malloc(
 460                 db_data.dsize - sizeof(struct share_mode_entry));
 461         if (!new_data_p) {
 462                 free(db_data.dptr);
 463                 return -1;
 464         }
 465
 466         /* Copy the header. */
 467         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data));
 468
 469         num_share_modes = 0;
 470         for (i = 0; i < orig_num_share_modes; i++) {
 471                 struct share_mode_entry *share = &shares[i];
 472                 struct server_id pid = share->pid;
 473
 474                 /* Check this process really exists. */
 475                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 476                         continue; /* No longer exists. */
 477                 }
 478
 479                 if (share_mode_entry_equal(del_entry, share)) {
 480                         continue; /* This is our delete taget. */
 481                 }
 482
 483                 memcpy(new_data_p + sizeof(struct locking_data) +
 484                                 (num_share_modes * sizeof(struct share_mode_entry)),
 485                         share, sizeof(struct share_mode_entry) );
 486
 487                 num_share_modes++;
 488         }
 489
 490         if (num_share_modes == 0) {
 491                 /* None left after pruning. Delete record. */
 492                 free(db_data.dptr);
 493                 free(new_data_p);
 494                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 495         }
 496
 497         /* Copy any delete tokens plus the terminating filenames. */
 498         remaining_ptr = db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry));
 499         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 500
 501         memcpy(new_data_p + sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)),
 502                 remaining_ptr,
 503                 remaining_size);
 504
 505         free(db_data.dptr);
 506
 507         db_data.dptr = new_data_p;
 508
 509         /* Re-save smaller record. */
 510         ld = (struct locking_data *)db_data.dptr;
 511         ld->u.s.num_share_mode_entries = num_share_modes;
 512
 513         db_data.dsize = sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)) + remaining_size;
 514
 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 }
 522
 523 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 524                                 uint64_t dev,
 525                                 uint64_t ino,
 526                                 uint64_t extid,
 527                                 const struct smb_share_mode_entry *set_entry,
 528                                 const struct smb_share_mode_entry *new_entry)
 529 {
 530         TDB_DATA db_data;
 531         struct locking_key lk;
 532         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 533         int num_share_modes = 0;
 534         struct locking_data *ld = NULL; /* internal samba db state. */
 535         struct share_mode_entry *shares = NULL;
 536         size_t i;
 537         int found_entry = 0;
 538
 539         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 540         if (!db_data.dptr) {
 541                 return -1; /* Error - missing entry ! */
 542         }
 543
 544         ld = (struct locking_data *)db_data.dptr;
 545         num_share_modes = ld->u.s.num_share_mode_entries;
 546         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 547
 548         for (i = 0; i < num_share_modes; i++) {
 549                 struct share_mode_entry *share = &shares[i];
 550                 struct server_id pid = share->pid;
 551
 552                 /* Check this process really exists. */
 553                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 554                         continue; /* No longer exists. */
 555                 }
 556
 557                 if (share_mode_entry_equal(set_entry, share)) {
 558                         create_share_mode_entry(share, new_entry, share->name_hash);
 559                         found_entry = 1;
 560                         break;
 561                 }
 562         }
 563
 564         if (!found_entry) {
 565                 free(db_data.dptr);
 566                 return -1;
 567         }
 568
 569         /* Save modified data. */
 570         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 571                 free(db_data.dptr);
 572                 return -1;
 573         }
 574         free(db_data.dptr);
 575         return 0;
 576 }