source3/lib/util_tdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    tdb utility functions
   4    Copyright (C) Andrew Tridgell   1992-1998
   5    Copyright (C) Rafal Szczesniak  2002
   6    Copyright (C) Michael Adam      2007
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "system/filesys.h"
  24 #include "util_tdb.h"
  25
  26 #undef malloc
  27 #undef realloc
  28 #undef calloc
  29 #undef strdup
  30
  31 /* these are little tdb utility functions that are meant to make
  32    dealing with a tdb database a little less cumbersome in Samba */
  33
  34 int tdb_trans_store_bystring(TDB_CONTEXT *tdb, const char *keystr,
  35                              TDB_DATA data, int flags)
  36 {
  37         TDB_DATA key = string_term_tdb_data(keystr);
  38
  39         return tdb_trans_store(tdb, key, data, flags);
  40 }
  41
  42 /****************************************************************************
  43  Useful pair of routines for packing/unpacking data consisting of
  44  integers and strings.
  45 ****************************************************************************/
  46
  47 static size_t tdb_pack_va(uint8 *buf, int bufsize, const char *fmt, va_list ap)
  48 {
  49         uint8 bt;
  50         uint16 w;
  51         uint32 d;
  52         int i;
  53         void *p;
  54         int len;
  55         char *s;
  56         char c;
  57         uint8 *buf0 = buf;
  58         const char *fmt0 = fmt;
  59         int bufsize0 = bufsize;
  60
  61         while (*fmt) {
  62                 switch ((c = *fmt++)) {
  63                 case 'b': /* unsigned 8-bit integer */
  64                         len = 1;
  65                         bt = (uint8)va_arg(ap, int);
  66                         if (bufsize && bufsize >= len)
  67                                 SSVAL(buf, 0, bt);
  68                         break;
  69                 case 'w': /* unsigned 16-bit integer */
  70                         len = 2;
  71                         w = (uint16)va_arg(ap, int);
  72                         if (bufsize && bufsize >= len)
  73                                 SSVAL(buf, 0, w);
  74                         break;
  75                 case 'd': /* signed 32-bit integer (standard int in most systems) */
  76                         len = 4;
  77                         d = va_arg(ap, uint32);
  78                         if (bufsize && bufsize >= len)
  79                                 SIVAL(buf, 0, d);
  80                         break;
  81                 case 'p': /* pointer */
  82                         len = 4;
  83                         p = va_arg(ap, void *);
  84                         d = p?1:0;
  85                         if (bufsize && bufsize >= len)
  86                                 SIVAL(buf, 0, d);
  87                         break;
  88                 case 'P': /* null-terminated string */
  89                         s = va_arg(ap,char *);
  90                         w = strlen(s);
  91                         len = w + 1;
  92                         if (bufsize && bufsize >= len)
  93                                 memcpy(buf, s, len);
  94                         break;
  95                 case 'f': /* null-terminated string */
  96                         s = va_arg(ap,char *);
  97                         w = strlen(s);
  98                         len = w + 1;
  99                         if (bufsize && bufsize >= len)
 100                                 memcpy(buf, s, len);
 101                         break;
 102                 case 'B': /* fixed-length string */
 103                         i = va_arg(ap, int);
 104                         s = va_arg(ap, char *);
 105                         len = 4+i;
 106                         if (bufsize && bufsize >= len) {
 107                                 SIVAL(buf, 0, i);
 108                                 memcpy(buf+4, s, i);
 109                         }
 110                         break;
 111                 default:
 112                         DEBUG(0,("Unknown tdb_pack format %c in %s\n",
 113                                  c, fmt));
 114                         len = 0;
 115                         break;
 116                 }
 117
 118                 buf += len;
 119                 if (bufsize)
 120                         bufsize -= len;
 121                 if (bufsize < 0)
 122                         bufsize = 0;
 123         }
 124
 125         DEBUG(18,("tdb_pack_va(%s, %d) -> %d\n",
 126                  fmt0, bufsize0, (int)PTR_DIFF(buf, buf0)));
 127
 128         return PTR_DIFF(buf, buf0);
 129 }
 130
 131 size_t tdb_pack(uint8 *buf, int bufsize, const char *fmt, ...)
 132 {
 133         va_list ap;
 134         size_t result;
 135
 136         va_start(ap, fmt);
 137         result = tdb_pack_va(buf, bufsize, fmt, ap);
 138         va_end(ap);
 139         return result;
 140 }
 141
 142 bool tdb_pack_append(TALLOC_CTX *mem_ctx, uint8 **buf, size_t *len,
 143                      const char *fmt, ...)
 144 {
 145         va_list ap;
 146         size_t len1, len2;
 147
 148         va_start(ap, fmt);
 149         len1 = tdb_pack_va(NULL, 0, fmt, ap);
 150         va_end(ap);
 151
 152         if (mem_ctx != NULL) {
 153                 *buf = talloc_realloc(mem_ctx, *buf, uint8,
 154                                             (*len) + len1);
 155         } else {
 156                 *buf = SMB_REALLOC_ARRAY(*buf, uint8, (*len) + len1);
 157         }
 158
 159         if (*buf == NULL) {
 160                 return False;
 161         }
 162
 163         va_start(ap, fmt);
 164         len2 = tdb_pack_va((*buf)+(*len), len1, fmt, ap);
 165         va_end(ap);
 166
 167         if (len1 != len2) {
 168                 return False;
 169         }
 170
 171         *len += len2;
 172
 173         return True;
 174 }
 175
 176 /****************************************************************************
 177  Useful pair of routines for packing/unpacking data consisting of
 178  integers and strings.
 179 ****************************************************************************/
 180
 181 int tdb_unpack(const uint8 *buf, int bufsize, const char *fmt, ...)
 182 {
 183         va_list ap;
 184         uint8 *bt;
 185         uint16 *w;
 186         uint32 *d;
 187         int len;
 188         int *i;
 189         void **p;
 190         char *s, **b, **ps;
 191         char c;
 192         const uint8 *buf0 = buf;
 193         const char *fmt0 = fmt;
 194         int bufsize0 = bufsize;
 195
 196         va_start(ap, fmt);
 197
 198         while (*fmt) {
 199                 switch ((c=*fmt++)) {
 200                 case 'b': /* unsigned 8-bit integer */
 201                         len = 1;
 202                         bt = va_arg(ap, uint8 *);
 203                         if (bufsize < len)
 204                                 goto no_space;
 205                         *bt = SVAL(buf, 0);
 206                         break;
 207                 case 'w': /* unsigned 16-bit integer */
 208                         len = 2;
 209                         w = va_arg(ap, uint16 *);
 210                         if (bufsize < len)
 211                                 goto no_space;
 212                         *w = SVAL(buf, 0);
 213                         break;
 214                 case 'd': /* unsigned 32-bit integer (standard int in most systems) */
 215                         len = 4;
 216                         d = va_arg(ap, uint32 *);
 217                         if (bufsize < len)
 218                                 goto no_space;
 219                         *d = IVAL(buf, 0);
 220                         break;
 221                 case 'p': /* pointer */
 222                         len = 4;
 223                         p = va_arg(ap, void **);
 224                         if (bufsize < len)
 225                                 goto no_space;
 226                         /*
 227                          * This isn't a real pointer - only a token (1 or 0)
 228                          * to mark the fact a pointer is present.
 229                          */
 230
 231                         *p = (void *)(IVAL(buf, 0) ? (void *)1 : NULL);
 232                         break;
 233                 case 'P': /* null-terminated string */
 234                         /* Return malloc'ed string. */
 235                         ps = va_arg(ap,char **);
 236                         len = strnlen((const char *)buf, bufsize) + 1;
 237                         if (bufsize < len)
 238                                 goto no_space;
 239                         *ps = SMB_STRDUP((const char *)buf);
 240                         if (*ps == NULL) {
 241                                 goto no_space;
 242                         }
 243                         break;
 244                 case 'f': /* null-terminated string */
 245                         s = va_arg(ap,char *);
 246                         len = strnlen((const char *)buf, bufsize) + 1;
 247                         if (bufsize < len || len > sizeof(fstring))
 248                                 goto no_space;
 249                         memcpy(s, buf, len);
 250                         break;
 251                 case 'B': /* fixed-length string */
 252                         i = va_arg(ap, int *);
 253                         b = va_arg(ap, char **);
 254                         len = 4;
 255                         if (bufsize < len)
 256                                 goto no_space;
 257                         *i = IVAL(buf, 0);
 258                         if (! *i) {
 259                                 *b = NULL;
 260                                 break;
 261                         }
 262                         len += *i;
 263                         if (bufsize < len)
 264                                 goto no_space;
 265                         *b = (char *)SMB_MALLOC(*i);
 266                         if (! *b)
 267                                 goto no_space;
 268                         memcpy(*b, buf+4, *i);
 269                         break;
 270                 default:
 271                         DEBUG(0,("Unknown tdb_unpack format %c in %s\n",
 272                                  c, fmt));
 273
 274                         len = 0;
 275                         break;
 276                 }
 277
 278                 buf += len;
 279                 bufsize -= len;
 280         }
 281
 282         va_end(ap);
 283
 284         DEBUG(18,("tdb_unpack(%s, %d) -> %d\n",
 285                  fmt0, bufsize0, (int)PTR_DIFF(buf, buf0)));
 286
 287         return PTR_DIFF(buf, buf0);
 288
 289  no_space:
 290         va_end(ap);
 291         return -1;
 292 }
 293
 294
 295 /****************************************************************************
 296  Log tdb messages via DEBUG().
 297 ****************************************************************************/
 298
 299 static void tdb_log(TDB_CONTEXT *tdb, enum tdb_debug_level level, const char *format, ...)
 300 {
 301         va_list ap;
 302         char *ptr = NULL;
 303         int ret;
 304
 305         va_start(ap, format);
 306         ret = vasprintf(&ptr, format, ap);
 307         va_end(ap);
 308
 309         if ((ret == -1) || !*ptr)
 310                 return;
 311
 312         DEBUG((int)level, ("tdb(%s): %s", tdb_name(tdb) ? tdb_name(tdb) : "unnamed", ptr));
 313         SAFE_FREE(ptr);
 314 }
 315
 316 /****************************************************************************
 317  Like tdb_open() but also setup a logging function that redirects to
 318  the samba DEBUG() system.
 319 ****************************************************************************/
 320
 321 TDB_CONTEXT *tdb_open_log(const char *name, int hash_size, int tdb_flags,
 322                           int open_flags, mode_t mode)
 323 {
 324         TDB_CONTEXT *tdb;
 325
 326         if (!lp_use_mmap())
 327                 tdb_flags |= TDB_NOMMAP;
 328
 329         if ((hash_size == 0) && (name != NULL)) {
 330                 const char *base = strrchr_m(name, '/');
 331                 if (base != NULL) {
 332                         base += 1;
 333                 }
 334                 else {
 335                         base = name;
 336                 }
 337                 hash_size = lp_parm_int(-1, "tdb_hashsize", base, 0);
 338         }
 339
 340         tdb = tdb_open_compat(name, hash_size, tdb_flags,
 341                               open_flags, mode, tdb_log, NULL);
 342         if (!tdb)
 343                 return NULL;
 344
 345         return tdb;
 346 }
 347
 348 /****************************************************************************
 349  tdb_store, wrapped in a transaction. This way we make sure that a process
 350  that dies within writing does not leave a corrupt tdb behind.
 351 ****************************************************************************/
 352
 353 int tdb_trans_store(struct tdb_context *tdb, TDB_DATA key, TDB_DATA dbuf,
 354                     int flag)
 355 {
 356         int res;
 357
 358         if ((res = tdb_transaction_start(tdb)) != 0) {
 359                 DEBUG(5, ("tdb_transaction_start failed\n"));
 360                 return res;
 361         }
 362
 363         if ((res = tdb_store(tdb, key, dbuf, flag)) != 0) {
 364                 DEBUG(10, ("tdb_store failed\n"));
 365                 tdb_transaction_cancel(tdb);
 366                 return res;
 367         }
 368
 369         if ((res = tdb_transaction_commit(tdb)) != 0) {
 370                 DEBUG(5, ("tdb_transaction_commit failed\n"));
 371         }
 372
 373         return res;
 374 }
 375
 376 /****************************************************************************
 377  tdb_delete, wrapped in a transaction. This way we make sure that a process
 378  that dies within deleting does not leave a corrupt tdb behind.
 379 ****************************************************************************/
 380
 381 int tdb_trans_delete(struct tdb_context *tdb, TDB_DATA key)
 382 {
 383         int res;
 384
 385         if ((res = tdb_transaction_start(tdb)) != 0) {
 386                 DEBUG(5, ("tdb_transaction_start failed\n"));
 387                 return res;
 388         }
 389
 390         if ((res = tdb_delete(tdb, key)) != 0) {
 391                 DEBUG(10, ("tdb_delete failed\n"));
 392                 tdb_transaction_cancel(tdb);
 393                 return res;
 394         }
 395
 396         if ((res = tdb_transaction_commit(tdb)) != 0) {
 397                 DEBUG(5, ("tdb_transaction_commit failed\n"));
 398         }
 399
 400         return res;
 401 }
 402
 403 int tdb_data_cmp(TDB_DATA t1, TDB_DATA t2)
 404 {
 405         int ret;
 406         if (t1.dptr == NULL && t2.dptr != NULL) {
 407                 return -1;
 408         }
 409         if (t1.dptr != NULL && t2.dptr == NULL) {
 410                 return 1;
 411         }
 412         if (t1.dptr == t2.dptr) {
 413                 return t1.dsize - t2.dsize;
 414         }
 415         ret = memcmp(t1.dptr, t2.dptr, MIN(t1.dsize, t2.dsize));
 416         if (ret == 0) {
 417                 return t1.dsize - t2.dsize;
 418         }
 419         return ret;
 420 }