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 = malloc((2*sizeof(struct share_mode_entry)) +
 263                                         strlen(sharepath) + 1 +
 264                                         strlen(filename) + 1);
 265                 if (!db_data.dptr) {
 266                         return -1;
 267                 }
 268                 ld = (struct locking_data *)db_data.dptr;
 269                 memset(ld, '\0', sizeof(struct locking_data));
 270                 ld->u.s.num_share_mode_entries = 1;
 271                 ld->u.s.delete_on_close = 0;
 272                 ld->u.s.initial_delete_on_close = 0;
 273                 ld->u.s.delete_token_size = 0;
 274                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct share_mode_entry));
 275                 create_share_mode_entry(shares, new_entry);
 276
 277                 memcpy(db_data.dptr + 2*sizeof(struct share_mode_entry),
 278                         sharepath,
 279                         strlen(sharepath) + 1);
 280                 memcpy(db_data.dptr + 2*sizeof(struct share_mode_entry) +
 281                         strlen(sharepath) + 1,
 282                         filename,
 283                         strlen(filename) + 1);
 284
 285                 db_data.dsize = 2*sizeof(struct share_mode_entry) +
 286                                         strlen(sharepath) + 1 +
 287                                         strlen(filename) + 1;
 288                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) == -1) {
 289                         free(db_data.dptr);
 290                         return -1;
 291                 }
 292                 free(db_data.dptr);
 293                 return 0;
 294         }
 295
 296         /* Entry exists, we must add a new entry. */
 297         new_data_p = malloc(db_data.dsize + sizeof(struct share_mode_entry));
 298         if (!new_data_p) {
 299                 free(db_data.dptr);
 300                 return -1;
 301         }
 302
 303         ld = (struct locking_data *)db_data.dptr;
 304         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 305
 306         /* Copy the original data. */
 307         memcpy(new_data_p, db_data.dptr, (orig_num_share_modes+1)*sizeof(struct share_mode_entry));
 308
 309         /* Add in the new share mode */
 310         shares = (struct share_mode_entry *)(new_data_p +
 311                         ((orig_num_share_modes+1)*sizeof(struct share_mode_entry)));
 312
 313         create_share_mode_entry(shares, new_entry);
 314
 315         ld = (struct locking_data *)new_data_p;
 316         ld->u.s.num_share_mode_entries++;
 317
 318         /* Append the original delete_token and filenames. */
 319         memcpy(new_data_p + ((ld->u.s.num_share_mode_entries+1)*sizeof(struct share_mode_entry)),
 320                 db_data.dptr + ((orig_num_share_modes+1)*sizeof(struct share_mode_entry)),
 321                 db_data.dsize - ((orig_num_share_modes+1) * sizeof(struct share_mode_entry)));
 322
 323         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 324
 325         free(db_data.dptr);
 326
 327         db_data.dptr = new_data_p;
 328         db_data.dsize = new_data_size;
 329
 330         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 331                 free(db_data.dptr);
 332                 return -1;
 333         }
 334         free(db_data.dptr);
 335         return 0;
 336 }
 337
 338 /*
 339  * Create an entry in the Samba share mode db. Original interface - doesn't
 340  * Distinguish between share path and filename. Fudge this by using a
 341  * sharepath of / and a relative filename of (filename+1).
 342  */
 343
 344 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 345                                 uint64_t dev,
 346                                 uint64_t ino,
 347                                 const struct smb_share_mode_entry *new_entry,
 348                                 const char *filename) /* Must be absolute utf8 path. */
 349 {
 350         if (*filename != '/') {
 351                 abort();
 352         }
 353         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, new_entry,
 354                                                 "/", &filename[1]);
 355 }
 356
 357 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 358                                 uint64_t dev,
 359                                 uint64_t ino,
 360                                 const struct smb_share_mode_entry *del_entry)
 361 {
 362         TDB_DATA db_data;
 363         TDB_DATA locking_key =  get_locking_key(dev, ino);
 364         int orig_num_share_modes = 0;
 365         struct locking_data *ld = NULL; /* internal samba db state. */
 366         struct share_mode_entry *shares = NULL;
 367         char *new_data_p = NULL;
 368         size_t remaining_size = 0;
 369         size_t i, num_share_modes;
 370         const char *remaining_ptr = NULL;
 371
 372         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 373         if (!db_data.dptr) {
 374                 return -1; /* Error - missing entry ! */
 375         }
 376
 377         ld = (struct locking_data *)db_data.dptr;
 378         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 379         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct share_mode_entry));
 380
 381         if (orig_num_share_modes == 1) {
 382                 /* Only one entry - better be ours... */
 383                 if (!share_mode_entry_equal(del_entry, shares)) {
 384                         /* Error ! We can't delete someone else's entry ! */
 385                         free(db_data.dptr);
 386                         return -1;
 387                 }
 388                 /* It's ours - just remove the entire record. */
 389                 free(db_data.dptr);
 390                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 391         }
 392
 393         /* More than one - allocate a new record minus the one we'll delete. */
 394         new_data_p = malloc(db_data.dsize - sizeof(struct share_mode_entry));
 395         if (!new_data_p) {
 396                 free(db_data.dptr);
 397                 return -1;
 398         }
 399
 400         /* Copy the header. */
 401         memcpy(new_data_p, db_data.dptr, sizeof(struct share_mode_entry));
 402
 403         num_share_modes = 0;
 404         for (i = 0; i < orig_num_share_modes; i++) {
 405                 struct share_mode_entry *share = &shares[i];
 406                 struct process_id pid = share->pid;
 407
 408                 /* Check this process really exists. */
 409                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 410                         continue; /* No longer exists. */
 411                 }
 412
 413                 if (share_mode_entry_equal(del_entry, share)) {
 414                         continue; /* This is our delete taget. */
 415                 }
 416
 417                 memcpy(new_data_p + ((num_share_modes+1)*sizeof(struct share_mode_entry)),
 418                         share, sizeof(struct share_mode_entry) );
 419
 420                 num_share_modes++;
 421         }
 422
 423         if (num_share_modes == 0) {
 424                 /* None left after pruning. Delete record. */
 425                 free(db_data.dptr);
 426                 free(new_data_p);
 427                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 428         }
 429
 430         /* Copy any delete token plus the terminating filenames. */
 431         remaining_ptr = db_data.dptr + ((orig_num_share_modes+1) * sizeof(struct share_mode_entry));
 432         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 433
 434         memcpy(new_data_p + ((num_share_modes+1)*sizeof(struct share_mode_entry)),
 435                 remaining_ptr,
 436                 remaining_size);
 437
 438         free(db_data.dptr);
 439
 440         db_data.dptr = new_data_p;
 441
 442         /* Re-save smaller record. */
 443         ld = (struct locking_data *)db_data.dptr;
 444         ld->u.s.num_share_mode_entries = num_share_modes;
 445
 446         db_data.dsize = ((num_share_modes+1)*sizeof(struct share_mode_entry)) + remaining_size;
 447
 448         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 449                 free(db_data.dptr);
 450                 return -1;
 451         }
 452         free(db_data.dptr);
 453         return 0;
 454 }
 455
 456 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 457                                 uint64_t dev,
 458                                 uint64_t ino,
 459                                 const struct smb_share_mode_entry *set_entry,
 460                                 const struct smb_share_mode_entry *new_entry)
 461 {
 462         TDB_DATA db_data;
 463         TDB_DATA locking_key =  get_locking_key(dev, ino);
 464         int num_share_modes = 0;
 465         struct locking_data *ld = NULL; /* internal samba db state. */
 466         struct share_mode_entry *shares = NULL;
 467         size_t i;
 468         int found_entry = 0;
 469
 470         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 471         if (!db_data.dptr) {
 472                 return -1; /* Error - missing entry ! */
 473         }
 474
 475         ld = (struct locking_data *)db_data.dptr;
 476         num_share_modes = ld->u.s.num_share_mode_entries;
 477         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct share_mode_entry));
 478
 479         for (i = 0; i < num_share_modes; i++) {
 480                 struct share_mode_entry *share = &shares[i];
 481                 struct process_id pid = share->pid;
 482
 483                 /* Check this process really exists. */
 484                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 485                         continue; /* No longer exists. */
 486                 }
 487
 488                 if (share_mode_entry_equal(set_entry, share)) {
 489                         create_share_mode_entry(share, new_entry);
 490                         found_entry = 1;
 491                         break;
 492                 }
 493         }
 494
 495         if (!found_entry) {
 496                 free(db_data.dptr);
 497                 return -1;
 498         }
 499
 500         /* Save modified data. */
 501         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 502                 free(db_data.dptr);
 503                 return -1;
 504         }
 505         free(db_data.dptr);
 506         return 0;
 507 }