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
  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, uint64_t extid,
  43                                 const struct smb_share_mode_entry *new_entry,
  44                                 const char *sharepath, const char *filename);
  45
  46 static bool sharemodes_procid_equal(const struct server_id *p1, const struct server_id *p2)
  47 {
  48         return (p1->pid == p2->pid);
  49 }
  50
  51 static pid_t sharemodes_procid_to_pid(const struct server_id *proc)
  52 {
  53         return proc->pid;
  54 }
  55
  56 /*
  57  * open/close sharemode database.
  58  */
  59
  60 struct smbdb_ctx *smb_share_mode_db_open(const char *db_path)
  61 {
  62         struct smbdb_ctx *smb_db = (struct smbdb_ctx *)malloc(sizeof(struct smbdb_ctx));
  63
  64         if (!smb_db) {
  65                 return NULL;
  66         }
  67
  68         memset(smb_db, '\0', sizeof(struct smbdb_ctx));
  69
  70         smb_db->smb_tdb = tdb_open(db_path,
  71                                 0, TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH,
  72                                 O_RDWR|O_CREAT,
  73                                 0644);
  74
  75         if (!smb_db->smb_tdb) {
  76                 free(smb_db);
  77                 return NULL;
  78         }
  79
  80         /* Should check that this is the correct version.... */
  81         return smb_db;
  82 }
  83
  84 /* key and data records in the tdb locking database */
  85 struct locking_key {
  86         SMB_DEV_T dev;
  87         SMB_INO_T inode;
  88         uint64_t extid;
  89 };
  90
  91 int smb_share_mode_db_close(struct smbdb_ctx *db_ctx)
  92 {
  93         int ret = tdb_close(db_ctx->smb_tdb);
  94         free(db_ctx);
  95         return ret;
  96 }
  97
  98 static TDB_DATA get_locking_key(struct locking_key *lk, uint64_t dev,
  99                                 uint64_t ino, uint64_t extid)
 100 {
 101         TDB_DATA ld;
 102
 103         memset(lk, '\0', sizeof(*lk));
 104         lk->dev = (SMB_DEV_T)dev;
 105         lk->inode = (SMB_INO_T)ino;
 106         lk->extid = extid;
 107         ld.dptr = (uint8 *)lk;
 108         ld.dsize = sizeof(*lk);
 109         return ld;
 110 }
 111
 112 /*
 113  * lock/unlock entry in sharemode database.
 114  */
 115
 116 int smb_lock_share_mode_entry(struct smbdb_ctx *db_ctx,
 117                                 uint64_t dev,
 118                                 uint64_t ino,
 119                                 uint64_t extid)
 120 {
 121         struct locking_key lk;
 122         return tdb_chainlock(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino,
 123                                                               extid));
 124 }
 125
 126 int smb_unlock_share_mode_entry(struct smbdb_ctx *db_ctx,
 127                                 uint64_t dev,
 128                                 uint64_t ino,
 129                                 uint64_t extid)
 130 {
 131         struct locking_key lk;
 132         return tdb_chainunlock(db_ctx->smb_tdb,
 133                                get_locking_key(&lk, dev, ino, extid));
 134 }
 135
 136 /*
 137  * Check if an external smb_share_mode_entry and an internal share_mode entry match.
 138  */
 139
 140 static int share_mode_entry_equal(const struct smb_share_mode_entry *e_entry,
 141                                 const struct share_mode_entry *entry)
 142 {
 143         return (sharemodes_procid_equal(&e_entry->pid, &entry->pid) &&
 144                 e_entry->file_id == (uint32_t)entry->share_file_id &&
 145                 e_entry->open_time.tv_sec == entry->time.tv_sec &&
 146                 e_entry->open_time.tv_usec == entry->time.tv_usec &&
 147                 e_entry->share_access == (uint32_t)entry->share_access &&
 148                 e_entry->access_mask == (uint32_t)entry->access_mask &&
 149                 e_entry->dev == entry->id.devid &&
 150                 e_entry->ino == entry->id.inode &&
 151                 e_entry->extid == entry->id.extid);
 152 }
 153
 154 /*
 155  * Create an internal Samba share_mode entry from an external smb_share_mode_entry.
 156  */
 157
 158 static void create_share_mode_entry(struct share_mode_entry *out,
 159                                 const struct smb_share_mode_entry *in,
 160                                 uint32_t name_hash)
 161 {
 162         memset(out, '\0', sizeof(struct share_mode_entry));
 163
 164         out->pid = in->pid;
 165         out->share_file_id = (unsigned long)in->file_id;
 166         out->time.tv_sec = in->open_time.tv_sec;
 167         out->time.tv_usec = in->open_time.tv_usec;
 168         out->share_access = in->share_access;
 169         out->access_mask = in->access_mask;
 170         out->id.devid = in->dev;
 171         out->id.inode = in->ino;
 172         out->id.extid = in->extid;
 173         out->uid = (uint32)geteuid();
 174         out->flags = 0;
 175         out->name_hash = name_hash;
 176 }
 177
 178 /*
 179  * Return the current share mode list for an open file.
 180  * This uses similar (but simplified) logic to locking/locking.c
 181  */
 182
 183 int smb_get_share_mode_entries(struct smbdb_ctx *db_ctx,
 184                                 uint64_t dev,
 185                                 uint64_t ino,
 186                                 uint64_t extid,
 187                                 struct smb_share_mode_entry **pp_list,
 188                                 unsigned char *p_delete_on_close)
 189 {
 190         struct locking_key lk;
 191         TDB_DATA db_data;
 192         struct smb_share_mode_entry *list = NULL;
 193         int num_share_modes = 0;
 194         struct locking_data *ld = NULL; /* internal samba db state. */
 195         struct share_mode_entry *shares = NULL;
 196         size_t i;
 197         int list_num;
 198
 199         *pp_list = NULL;
 200         *p_delete_on_close = 0;
 201
 202         db_data = tdb_fetch(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino,
 203                                                              extid));
 204         if (!db_data.dptr) {
 205                 return 0;
 206         }
 207
 208         ld = (struct locking_data *)db_data.dptr;
 209         num_share_modes = ld->u.s.num_share_mode_entries;
 210
 211         if (!num_share_modes) {
 212                 free(db_data.dptr);
 213                 return 0;
 214         }
 215
 216         list = (struct smb_share_mode_entry *)malloc(sizeof(struct smb_share_mode_entry)*num_share_modes);
 217         if (!list) {
 218                 free(db_data.dptr);
 219                 return -1;
 220         }
 221
 222         memset(list, '\0', num_share_modes * sizeof(struct smb_share_mode_entry));
 223
 224         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 225
 226         list_num = 0;
 227         for (i = 0; i < num_share_modes; i++) {
 228                 struct share_mode_entry *share = &shares[i];
 229                 struct smb_share_mode_entry *sme = &list[list_num];
 230                 struct server_id pid = share->pid;
 231
 232                 /* Check this process really exists. */
 233                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 234                         continue; /* No longer exists. */
 235                 }
 236
 237                 /* Ignore deferred open entries. */
 238                 if (share->op_type == DEFERRED_OPEN_ENTRY) {
 239                         continue;
 240                 }
 241
 242                 /* Copy into the external list. */
 243                 sme->dev = share->id.devid;
 244                 sme->ino = share->id.inode;
 245                 sme->extid = share->id.extid;
 246                 sme->share_access = (uint32_t)share->share_access;
 247                 sme->access_mask = (uint32_t)share->access_mask;
 248                 sme->open_time.tv_sec = share->time.tv_sec;
 249                 sme->open_time.tv_usec = share->time.tv_usec;
 250                 sme->file_id = (uint32_t)share->share_file_id;
 251                 sme->pid = share->pid;
 252                 list_num++;
 253         }
 254
 255         if (list_num == 0) {
 256                 free(db_data.dptr);
 257                 free(list);
 258                 return 0;
 259         }
 260
 261         *p_delete_on_close = ld->u.s.num_delete_token_entries != 0;
 262         *pp_list = list;
 263         free(db_data.dptr);
 264         return list_num;
 265 }
 266
 267 static uint32_t smb_name_hash(const char *sharepath, const char *filename, int *err)
 268 {
 269         TDB_DATA key;
 270         char *fullpath = NULL;
 271         size_t sharepath_size = strlen(sharepath);
 272         size_t filename_size = strlen(filename);
 273         uint32_t name_hash;
 274
 275         *err = 0;
 276         fullpath = (char *)malloc(sharepath_size + filename_size + 2);
 277         if (fullpath == NULL) {
 278                 *err = 1;
 279                 return 0;
 280         }
 281         memcpy(fullpath, sharepath, sharepath_size);
 282         fullpath[sharepath_size] = '/';
 283         memcpy(&fullpath[sharepath_size + 1], filename, filename_size + 1);
 284
 285         key.dptr = (uint8_t *)fullpath;
 286         key.dsize = strlen(fullpath) + 1;
 287         name_hash = tdb_jenkins_hash(&key);
 288         free(fullpath);
 289         return name_hash;
 290 }
 291
 292 /*
 293  * Create an entry in the Samba share mode db.
 294  */
 295
 296 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx,
 297                                 uint64_t dev,
 298                                 uint64_t ino,
 299                                 uint64_t extid,
 300                                 const struct smb_share_mode_entry *new_entry,
 301                                 const char *sharepath, /* Must be absolute utf8 path. */
 302                                 const char *filename) /* Must be relative utf8 path. */
 303 {
 304         TDB_DATA db_data;
 305         struct locking_key lk;
 306         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 307         int orig_num_share_modes = 0;
 308         struct locking_data *ld = NULL; /* internal samba db state. */
 309         struct share_mode_entry *shares = NULL;
 310         uint8 *new_data_p = NULL;
 311         size_t new_data_size = 0;
 312         int err = 0;
 313         uint32_t name_hash = smb_name_hash(sharepath, filename, &err);
 314
 315         if (err) {
 316                 return -1;
 317         }
 318
 319         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 320         if (!db_data.dptr) {
 321                 /* We must create the entry. */
 322                 db_data.dptr = (uint8 *)malloc(
 323                         sizeof(struct locking_data) +
 324                         sizeof(struct share_mode_entry) +
 325                         strlen(sharepath) + 1 +
 326                         strlen(filename) + 1);
 327                 if (!db_data.dptr) {
 328                         return -1;
 329                 }
 330                 ld = (struct locking_data *)db_data.dptr;
 331                 memset(ld, '\0', sizeof(struct locking_data));
 332                 ld->u.s.num_share_mode_entries = 1;
 333                 ld->u.s.num_delete_token_entries = 0;
 334                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 335                 create_share_mode_entry(shares, new_entry, name_hash);
 336
 337                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry),
 338                         sharepath,
 339                         strlen(sharepath) + 1);
 340                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 341                         strlen(sharepath) + 1,
 342                         filename,
 343                         strlen(filename) + 1);
 344
 345                 db_data.dsize = sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 346                                         strlen(sharepath) + 1 +
 347                                         strlen(filename) + 1;
 348                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) == -1) {
 349                         free(db_data.dptr);
 350                         return -1;
 351                 }
 352                 free(db_data.dptr);
 353                 return 0;
 354         }
 355
 356         /* Entry exists, we must add a new entry. */
 357         new_data_p = (uint8 *)malloc(
 358                 db_data.dsize + sizeof(struct share_mode_entry));
 359         if (!new_data_p) {
 360                 free(db_data.dptr);
 361                 return -1;
 362         }
 363
 364         ld = (struct locking_data *)db_data.dptr;
 365         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 366
 367         /* Copy the original data. */
 368         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)));
 369
 370         /* Add in the new share mode */
 371         shares = (struct share_mode_entry *)(new_data_p + sizeof(struct locking_data) +
 372                         (orig_num_share_modes * sizeof(struct share_mode_entry)));
 373
 374         create_share_mode_entry(shares, new_entry, name_hash);
 375
 376         ld = (struct locking_data *)new_data_p;
 377         ld->u.s.num_share_mode_entries++;
 378
 379         /* Append the original delete_tokens and filenames. */
 380         memcpy(new_data_p + sizeof(struct locking_data) + (ld->u.s.num_share_mode_entries * sizeof(struct share_mode_entry)),
 381                 db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)),
 382                 db_data.dsize - sizeof(struct locking_data) - (orig_num_share_modes * sizeof(struct share_mode_entry)));
 383
 384         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 385
 386         free(db_data.dptr);
 387
 388         db_data.dptr = new_data_p;
 389         db_data.dsize = new_data_size;
 390
 391         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 392                 free(db_data.dptr);
 393                 return -1;
 394         }
 395         free(db_data.dptr);
 396         return 0;
 397 }
 398
 399 /*
 400  * Create an entry in the Samba share mode db. Original interface - doesn't
 401  * Distinguish between share path and filename. Fudge this by using a
 402  * sharepath of / and a relative filename of (filename+1).
 403  */
 404
 405 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 406                                 uint64_t dev,
 407                                 uint64_t ino,
 408                                 uint64_t extid,
 409                                 const struct smb_share_mode_entry *new_entry,
 410                                 const char *filename) /* Must be absolute utf8 path. */
 411 {
 412         if (*filename != '/') {
 413                 abort();
 414         }
 415         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, extid, new_entry,
 416                                                 "/", &filename[1]);
 417 }
 418
 419 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 420                                 uint64_t dev,
 421                                 uint64_t ino,
 422                                 uint64_t extid,
 423                                 const struct smb_share_mode_entry *del_entry)
 424 {
 425         TDB_DATA db_data;
 426         struct locking_key lk;
 427         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 428         int orig_num_share_modes = 0;
 429         struct locking_data *ld = NULL; /* internal samba db state. */
 430         struct share_mode_entry *shares = NULL;
 431         uint8 *new_data_p = NULL;
 432         size_t remaining_size = 0;
 433         size_t i, num_share_modes;
 434         const uint8 *remaining_ptr = NULL;
 435
 436         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 437         if (!db_data.dptr) {
 438                 return -1; /* Error - missing entry ! */
 439         }
 440
 441         ld = (struct locking_data *)db_data.dptr;
 442         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 443         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 444
 445         if (orig_num_share_modes == 1) {
 446                 /* Only one entry - better be ours... */
 447                 if (!share_mode_entry_equal(del_entry, shares)) {
 448                         /* Error ! We can't delete someone else's entry ! */
 449                         free(db_data.dptr);
 450                         return -1;
 451                 }
 452                 /* It's ours - just remove the entire record. */
 453                 free(db_data.dptr);
 454                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 455         }
 456
 457         /* More than one - allocate a new record minus the one we'll delete. */
 458         new_data_p = (uint8 *)malloc(
 459                 db_data.dsize - sizeof(struct share_mode_entry));
 460         if (!new_data_p) {
 461                 free(db_data.dptr);
 462                 return -1;
 463         }
 464
 465         /* Copy the header. */
 466         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data));
 467
 468         num_share_modes = 0;
 469         for (i = 0; i < orig_num_share_modes; i++) {
 470                 struct share_mode_entry *share = &shares[i];
 471                 struct server_id pid = share->pid;
 472
 473                 /* Check this process really exists. */
 474                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 475                         continue; /* No longer exists. */
 476                 }
 477
 478                 if (share_mode_entry_equal(del_entry, share)) {
 479                         continue; /* This is our delete taget. */
 480                 }
 481
 482                 memcpy(new_data_p + sizeof(struct locking_data) +
 483                                 (num_share_modes * sizeof(struct share_mode_entry)),
 484                         share, sizeof(struct share_mode_entry) );
 485
 486                 num_share_modes++;
 487         }
 488
 489         if (num_share_modes == 0) {
 490                 /* None left after pruning. Delete record. */
 491                 free(db_data.dptr);
 492                 free(new_data_p);
 493                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 494         }
 495
 496         /* Copy any delete tokens plus the terminating filenames. */
 497         remaining_ptr = db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry));
 498         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 499
 500         memcpy(new_data_p + sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)),
 501                 remaining_ptr,
 502                 remaining_size);
 503
 504         free(db_data.dptr);
 505
 506         db_data.dptr = new_data_p;
 507
 508         /* Re-save smaller record. */
 509         ld = (struct locking_data *)db_data.dptr;
 510         ld->u.s.num_share_mode_entries = num_share_modes;
 511
 512         db_data.dsize = sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)) + remaining_size;
 513
 514         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 515                 free(db_data.dptr);
 516                 return -1;
 517         }
 518         free(db_data.dptr);
 519         return 0;
 520 }
 521
 522 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 523                                 uint64_t dev,
 524                                 uint64_t ino,
 525                                 uint64_t extid,
 526                                 const struct smb_share_mode_entry *set_entry,
 527                                 const struct smb_share_mode_entry *new_entry)
 528 {
 529         TDB_DATA db_data;
 530         struct locking_key lk;
 531         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 532         int num_share_modes = 0;
 533         struct locking_data *ld = NULL; /* internal samba db state. */
 534         struct share_mode_entry *shares = NULL;
 535         size_t i;
 536         int found_entry = 0;
 537
 538         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 539         if (!db_data.dptr) {
 540                 return -1; /* Error - missing entry ! */
 541         }
 542
 543         ld = (struct locking_data *)db_data.dptr;
 544         num_share_modes = ld->u.s.num_share_mode_entries;
 545         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 546
 547         for (i = 0; i < num_share_modes; i++) {
 548                 struct share_mode_entry *share = &shares[i];
 549                 struct server_id pid = share->pid;
 550
 551                 /* Check this process really exists. */
 552                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 553                         continue; /* No longer exists. */
 554                 }
 555
 556                 if (share_mode_entry_equal(set_entry, share)) {
 557                         create_share_mode_entry(share, new_entry, share->name_hash);
 558                         found_entry = 1;
 559                         break;
 560                 }
 561         }
 562
 563         if (!found_entry) {
 564                 free(db_data.dptr);
 565                 return -1;
 566         }
 567
 568         /* Save modified data. */
 569         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 570                 free(db_data.dptr);
 571                 return -1;
 572         }
 573         free(db_data.dptr);
 574         return 0;
 575 }