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 #define UID_WRAPPER_NOT_REPLACE
  28 #include "includes.h"
  29 #include "system/filesys.h"
  30 #include "smb_share_modes.h"
  31 #include "tdb_compat.h"
  32 #include <ccan/hash/hash.h>
  33
  34 /* Database context handle. */
  35 struct smbdb_ctx {
  36         TDB_CONTEXT *smb_tdb;
  37 };
  38
  39 /* Remove the paranoid malloc checker. */
  40 #ifdef malloc
  41 #undef malloc
  42 #endif
  43
  44 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx, uint64_t dev,
  45                                 uint64_t ino, uint64_t extid,
  46                                 const struct smb_share_mode_entry *new_entry,
  47                                 const char *sharepath, const char *filename);
  48
  49 static bool sharemodes_procid_equal(const struct server_id *p1, const struct server_id *p2)
  50 {
  51         return (p1->pid == p2->pid);
  52 }
  53
  54 static pid_t sharemodes_procid_to_pid(const struct server_id *proc)
  55 {
  56         return proc->pid;
  57 }
  58
  59 /*
  60  * open/close sharemode database.
  61  */
  62
  63 struct smbdb_ctx *smb_share_mode_db_open(const char *db_path)
  64 {
  65         struct smbdb_ctx *smb_db = (struct smbdb_ctx *)malloc(sizeof(struct smbdb_ctx));
  66
  67         if (!smb_db) {
  68                 return NULL;
  69         }
  70
  71         memset(smb_db, '\0', sizeof(struct smbdb_ctx));
  72
  73         /* FIXME: We should *never* open a tdb without logging! */
  74         smb_db->smb_tdb = tdb_open_compat(db_path,
  75                                           0, TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH,
  76                                           O_RDWR|O_CREAT,
  77                                           0644,
  78                                           NULL, NULL);
  79
  80         if (!smb_db->smb_tdb) {
  81                 free(smb_db);
  82                 return NULL;
  83         }
  84
  85         /* Should check that this is the correct version.... */
  86         return smb_db;
  87 }
  88
  89 /* key and data records in the tdb locking database */
  90 struct locking_key {
  91         SMB_DEV_T dev;
  92         SMB_INO_T inode;
  93         uint64_t extid;
  94 };
  95
  96 int smb_share_mode_db_close(struct smbdb_ctx *db_ctx)
  97 {
  98         int ret = tdb_close(db_ctx->smb_tdb);
  99         free(db_ctx);
 100         return ret;
 101 }
 102
 103 static TDB_DATA get_locking_key(struct locking_key *lk, uint64_t dev,
 104                                 uint64_t ino, uint64_t extid)
 105 {
 106         TDB_DATA ld;
 107
 108         memset(lk, '\0', sizeof(*lk));
 109         lk->dev = (SMB_DEV_T)dev;
 110         lk->inode = (SMB_INO_T)ino;
 111         lk->extid = extid;
 112         ld.dptr = (uint8 *)lk;
 113         ld.dsize = sizeof(*lk);
 114         return ld;
 115 }
 116
 117 /*
 118  * lock/unlock entry in sharemode database.
 119  */
 120
 121 int smb_lock_share_mode_entry(struct smbdb_ctx *db_ctx,
 122                                 uint64_t dev,
 123                                 uint64_t ino,
 124                                 uint64_t extid)
 125 {
 126         struct locking_key lk;
 127         return tdb_chainlock(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino,
 128                                                               extid)) == 0 ? 0 : -1;
 129 }
 130
 131 int smb_unlock_share_mode_entry(struct smbdb_ctx *db_ctx,
 132                                 uint64_t dev,
 133                                 uint64_t ino,
 134                                 uint64_t extid)
 135 {
 136         struct locking_key lk;
 137         tdb_chainunlock(db_ctx->smb_tdb,
 138                         get_locking_key(&lk, dev, ino, extid));
 139         return 0;
 140 }
 141
 142 /*
 143  * Check if an external smb_share_mode_entry and an internal share_mode entry match.
 144  */
 145
 146 static int share_mode_entry_equal(const struct smb_share_mode_entry *e_entry,
 147                                 const struct share_mode_entry *entry)
 148 {
 149         return (sharemodes_procid_equal(&e_entry->pid, &entry->pid) &&
 150                 e_entry->file_id == (uint32_t)entry->share_file_id &&
 151                 e_entry->open_time.tv_sec == entry->time.tv_sec &&
 152                 e_entry->open_time.tv_usec == entry->time.tv_usec &&
 153                 e_entry->share_access == (uint32_t)entry->share_access &&
 154                 e_entry->access_mask == (uint32_t)entry->access_mask &&
 155                 e_entry->dev == entry->id.devid &&
 156                 e_entry->ino == entry->id.inode &&
 157                 e_entry->extid == entry->id.extid);
 158 }
 159
 160 /*
 161  * Create an internal Samba share_mode entry from an external smb_share_mode_entry.
 162  */
 163
 164 static void create_share_mode_entry(struct share_mode_entry *out,
 165                                 const struct smb_share_mode_entry *in,
 166                                 uint32_t name_hash)
 167 {
 168         memset(out, '\0', sizeof(struct share_mode_entry));
 169
 170         out->pid = in->pid;
 171         out->share_file_id = (unsigned long)in->file_id;
 172         out->time.tv_sec = in->open_time.tv_sec;
 173         out->time.tv_usec = in->open_time.tv_usec;
 174         out->share_access = in->share_access;
 175         out->access_mask = in->access_mask;
 176         out->id.devid = in->dev;
 177         out->id.inode = in->ino;
 178         out->id.extid = in->extid;
 179         out->uid = (uint32)geteuid();
 180         out->flags = 0;
 181         out->name_hash = name_hash;
 182 }
 183
 184 /*
 185  * Return the current share mode list for an open file.
 186  * This uses similar (but simplified) logic to locking/locking.c
 187  */
 188
 189 int smb_get_share_mode_entries(struct smbdb_ctx *db_ctx,
 190                                 uint64_t dev,
 191                                 uint64_t ino,
 192                                 uint64_t extid,
 193                                 struct smb_share_mode_entry **pp_list,
 194                                 unsigned char *p_delete_on_close)
 195 {
 196         struct locking_key lk;
 197         TDB_DATA db_data;
 198         struct smb_share_mode_entry *list = NULL;
 199         int num_share_modes = 0;
 200         struct locking_data *ld = NULL; /* internal samba db state. */
 201         struct share_mode_entry *shares = NULL;
 202         size_t i;
 203         int list_num;
 204
 205         *pp_list = NULL;
 206         *p_delete_on_close = 0;
 207
 208         db_data = tdb_fetch_compat(db_ctx->smb_tdb,
 209                                    get_locking_key(&lk, dev, ino, extid));
 210         if (!db_data.dptr) {
 211                 return 0;
 212         }
 213
 214         ld = (struct locking_data *)db_data.dptr;
 215         num_share_modes = ld->u.s.num_share_mode_entries;
 216
 217         if (!num_share_modes) {
 218                 free(db_data.dptr);
 219                 return 0;
 220         }
 221
 222         list = (struct smb_share_mode_entry *)malloc(sizeof(struct smb_share_mode_entry)*num_share_modes);
 223         if (!list) {
 224                 free(db_data.dptr);
 225                 return -1;
 226         }
 227
 228         memset(list, '\0', num_share_modes * sizeof(struct smb_share_mode_entry));
 229
 230         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 231
 232         list_num = 0;
 233         for (i = 0; i < num_share_modes; i++) {
 234                 struct share_mode_entry *share = &shares[i];
 235                 struct smb_share_mode_entry *sme = &list[list_num];
 236                 struct server_id pid = share->pid;
 237
 238                 /* Check this process really exists. */
 239                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 240                         continue; /* No longer exists. */
 241                 }
 242
 243                 /* Ignore deferred open entries. */
 244                 if (share->op_type == DEFERRED_OPEN_ENTRY) {
 245                         continue;
 246                 }
 247
 248                 /* Copy into the external list. */
 249                 sme->dev = share->id.devid;
 250                 sme->ino = share->id.inode;
 251                 sme->extid = share->id.extid;
 252                 sme->share_access = (uint32_t)share->share_access;
 253                 sme->access_mask = (uint32_t)share->access_mask;
 254                 sme->open_time.tv_sec = share->time.tv_sec;
 255                 sme->open_time.tv_usec = share->time.tv_usec;
 256                 sme->file_id = (uint32_t)share->share_file_id;
 257                 sme->pid = share->pid;
 258                 list_num++;
 259         }
 260
 261         if (list_num == 0) {
 262                 free(db_data.dptr);
 263                 free(list);
 264                 return 0;
 265         }
 266
 267         *p_delete_on_close = ld->u.s.num_delete_token_entries != 0;
 268         *pp_list = list;
 269         free(db_data.dptr);
 270         return list_num;
 271 }
 272
 273 static uint32_t smb_name_hash(const char *sharepath, const char *filename, int *err)
 274 {
 275         char *fullpath = NULL;
 276         size_t sharepath_size = strlen(sharepath);
 277         size_t filename_size = strlen(filename);
 278         uint32_t name_hash;
 279
 280         *err = 0;
 281         fullpath = (char *)malloc(sharepath_size + filename_size + 2);
 282         if (fullpath == NULL) {
 283                 *err = 1;
 284                 return 0;
 285         }
 286         memcpy(fullpath, sharepath, sharepath_size);
 287         fullpath[sharepath_size] = '/';
 288         memcpy(&fullpath[sharepath_size + 1], filename, filename_size + 1);
 289
 290         name_hash = hash(fullpath, strlen(fullpath) + 1, 0);
 291         free(fullpath);
 292         return name_hash;
 293 }
 294
 295 /*
 296  * Create an entry in the Samba share mode db.
 297  */
 298
 299 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx,
 300                                 uint64_t dev,
 301                                 uint64_t ino,
 302                                 uint64_t extid,
 303                                 const struct smb_share_mode_entry *new_entry,
 304                                 const char *sharepath, /* Must be absolute utf8 path. */
 305                                 const char *filename) /* Must be relative utf8 path. */
 306 {
 307         TDB_DATA db_data;
 308         struct locking_key lk;
 309         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 310         int orig_num_share_modes = 0;
 311         struct locking_data *ld = NULL; /* internal samba db state. */
 312         struct share_mode_entry *shares = NULL;
 313         uint8 *new_data_p = NULL;
 314         size_t new_data_size = 0;
 315         int err = 0;
 316         uint32_t name_hash = smb_name_hash(sharepath, filename, &err);
 317
 318         if (err) {
 319                 return -1;
 320         }
 321
 322         db_data = tdb_fetch_compat(db_ctx->smb_tdb, locking_key);
 323         if (!db_data.dptr) {
 324                 /* We must create the entry. */
 325                 db_data.dptr = (uint8 *)malloc(
 326                         sizeof(struct locking_data) +
 327                         sizeof(struct share_mode_entry) +
 328                         strlen(sharepath) + 1 +
 329                         strlen(filename) + 1);
 330                 if (!db_data.dptr) {
 331                         return -1;
 332                 }
 333                 ld = (struct locking_data *)db_data.dptr;
 334                 memset(ld, '\0', sizeof(struct locking_data));
 335                 ld->u.s.num_share_mode_entries = 1;
 336                 ld->u.s.num_delete_token_entries = 0;
 337                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 338                 create_share_mode_entry(shares, new_entry, name_hash);
 339
 340                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry),
 341                         sharepath,
 342                         strlen(sharepath) + 1);
 343                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 344                         strlen(sharepath) + 1,
 345                         filename,
 346                         strlen(filename) + 1);
 347
 348                 db_data.dsize = sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 349                                         strlen(sharepath) + 1 +
 350                                         strlen(filename) + 1;
 351                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) != 0) {
 352                         free(db_data.dptr);
 353                         return -1;
 354                 }
 355                 free(db_data.dptr);
 356                 return 0;
 357         }
 358
 359         /* Entry exists, we must add a new entry. */
 360         new_data_p = (uint8 *)malloc(
 361                 db_data.dsize + sizeof(struct share_mode_entry));
 362         if (!new_data_p) {
 363                 free(db_data.dptr);
 364                 return -1;
 365         }
 366
 367         ld = (struct locking_data *)db_data.dptr;
 368         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 369
 370         /* Copy the original data. */
 371         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)));
 372
 373         /* Add in the new share mode */
 374         shares = (struct share_mode_entry *)(new_data_p + sizeof(struct locking_data) +
 375                         (orig_num_share_modes * sizeof(struct share_mode_entry)));
 376
 377         create_share_mode_entry(shares, new_entry, name_hash);
 378
 379         ld = (struct locking_data *)new_data_p;
 380         ld->u.s.num_share_mode_entries++;
 381
 382         /* Append the original delete_tokens and filenames. */
 383         memcpy(new_data_p + sizeof(struct locking_data) + (ld->u.s.num_share_mode_entries * sizeof(struct share_mode_entry)),
 384                 db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)),
 385                 db_data.dsize - sizeof(struct locking_data) - (orig_num_share_modes * sizeof(struct share_mode_entry)));
 386
 387         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 388
 389         free(db_data.dptr);
 390
 391         db_data.dptr = new_data_p;
 392         db_data.dsize = new_data_size;
 393
 394         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) != 0) {
 395                 free(db_data.dptr);
 396                 return -1;
 397         }
 398         free(db_data.dptr);
 399         return 0;
 400 }
 401
 402 /*
 403  * Create an entry in the Samba share mode db. Original interface - doesn't
 404  * Distinguish between share path and filename. Fudge this by using a
 405  * sharepath of / and a relative filename of (filename+1).
 406  */
 407
 408 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 409                                 uint64_t dev,
 410                                 uint64_t ino,
 411                                 uint64_t extid,
 412                                 const struct smb_share_mode_entry *new_entry,
 413                                 const char *filename) /* Must be absolute utf8 path. */
 414 {
 415         if (*filename != '/') {
 416                 abort();
 417         }
 418         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, extid, new_entry,
 419                                                 "/", &filename[1]);
 420 }
 421
 422 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 423                                 uint64_t dev,
 424                                 uint64_t ino,
 425                                 uint64_t extid,
 426                                 const struct smb_share_mode_entry *del_entry)
 427 {
 428         TDB_DATA db_data;
 429         struct locking_key lk;
 430         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 431         int orig_num_share_modes = 0;
 432         struct locking_data *ld = NULL; /* internal samba db state. */
 433         struct share_mode_entry *shares = NULL;
 434         uint8 *new_data_p = NULL;
 435         size_t remaining_size = 0;
 436         size_t i, num_share_modes;
 437         const uint8 *remaining_ptr = NULL;
 438
 439         db_data = tdb_fetch_compat(db_ctx->smb_tdb, locking_key);
 440         if (!db_data.dptr) {
 441                 return -1; /* Error - missing entry ! */
 442         }
 443
 444         ld = (struct locking_data *)db_data.dptr;
 445         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 446         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 447
 448         if (orig_num_share_modes == 1) {
 449                 /* Only one entry - better be ours... */
 450                 if (!share_mode_entry_equal(del_entry, shares)) {
 451                         /* Error ! We can't delete someone else's entry ! */
 452                         free(db_data.dptr);
 453                         return -1;
 454                 }
 455                 /* It's ours - just remove the entire record. */
 456                 free(db_data.dptr);
 457                 return tdb_delete(db_ctx->smb_tdb, locking_key) ? -1 : 0;
 458         }
 459
 460         /* More than one - allocate a new record minus the one we'll delete. */
 461         new_data_p = (uint8 *)malloc(
 462                 db_data.dsize - sizeof(struct share_mode_entry));
 463         if (!new_data_p) {
 464                 free(db_data.dptr);
 465                 return -1;
 466         }
 467
 468         /* Copy the header. */
 469         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data));
 470
 471         num_share_modes = 0;
 472         for (i = 0; i < orig_num_share_modes; i++) {
 473                 struct share_mode_entry *share = &shares[i];
 474                 struct server_id pid = share->pid;
 475
 476                 /* Check this process really exists. */
 477                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 478                         continue; /* No longer exists. */
 479                 }
 480
 481                 if (share_mode_entry_equal(del_entry, share)) {
 482                         continue; /* This is our delete taget. */
 483                 }
 484
 485                 memcpy(new_data_p + sizeof(struct locking_data) +
 486                                 (num_share_modes * sizeof(struct share_mode_entry)),
 487                         share, sizeof(struct share_mode_entry) );
 488
 489                 num_share_modes++;
 490         }
 491
 492         if (num_share_modes == 0) {
 493                 /* None left after pruning. Delete record. */
 494                 free(db_data.dptr);
 495                 free(new_data_p);
 496                 return tdb_delete(db_ctx->smb_tdb, locking_key) ? -1 : 0;
 497         }
 498
 499         /* Copy any delete tokens plus the terminating filenames. */
 500         remaining_ptr = db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry));
 501         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 502
 503         memcpy(new_data_p + sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)),
 504                 remaining_ptr,
 505                 remaining_size);
 506
 507         free(db_data.dptr);
 508
 509         db_data.dptr = new_data_p;
 510
 511         /* Re-save smaller record. */
 512         ld = (struct locking_data *)db_data.dptr;
 513         ld->u.s.num_share_mode_entries = num_share_modes;
 514
 515         db_data.dsize = sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)) + remaining_size;
 516
 517         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) != 0) {
 518                 free(db_data.dptr);
 519                 return -1;
 520         }
 521         free(db_data.dptr);
 522         return 0;
 523 }
 524
 525 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 526                                 uint64_t dev,
 527                                 uint64_t ino,
 528                                 uint64_t extid,
 529                                 const struct smb_share_mode_entry *set_entry,
 530                                 const struct smb_share_mode_entry *new_entry)
 531 {
 532         TDB_DATA db_data;
 533         struct locking_key lk;
 534         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino, extid);
 535         int num_share_modes = 0;
 536         struct locking_data *ld = NULL; /* internal samba db state. */
 537         struct share_mode_entry *shares = NULL;
 538         size_t i;
 539         int found_entry = 0;
 540
 541         db_data = tdb_fetch_compat(db_ctx->smb_tdb, locking_key);
 542         if (!db_data.dptr) {
 543                 return -1; /* Error - missing entry ! */
 544         }
 545
 546         ld = (struct locking_data *)db_data.dptr;
 547         num_share_modes = ld->u.s.num_share_mode_entries;
 548         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 549
 550         for (i = 0; i < num_share_modes; i++) {
 551                 struct share_mode_entry *share = &shares[i];
 552                 struct server_id pid = share->pid;
 553
 554                 /* Check this process really exists. */
 555                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 556                         continue; /* No longer exists. */
 557                 }
 558
 559                 if (share_mode_entry_equal(set_entry, share)) {
 560                         create_share_mode_entry(share, new_entry, share->name_hash);
 561                         found_entry = 1;
 562                         break;
 563                 }
 564         }
 565
 566         if (!found_entry) {
 567                 free(db_data.dptr);
 568                 return -1;
 569         }
 570
 571         /* Save modified data. */
 572         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) != 0) {
 573                 free(db_data.dptr);
 574                 return -1;
 575         }
 576         free(db_data.dptr);
 577         return 0;
 578 }