lib/smbconf/smbconf_txt.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  libsmbconf - Samba configuration library, text backend
   4  *  Copyright (C) Michael Adam 2008
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 /*
  21  * This is a sample implementation of a libsmbconf text backend
  22  * using the params.c parser.
  23  *
  24  * It is read only.
  25  * Don't expect brilliant performance, since it is not hashing the lists.
  26  */
  27
  28 #include "includes.h"
  29 #include "smbconf_private.h"
  30 #include "lib/smbconf/smbconf_txt.h"
  31
  32 struct txt_cache {
  33         uint32_t current_share;
  34         uint32_t num_shares;
  35         char **share_names;
  36         uint32_t *num_params;
  37         char ***param_names;
  38         char ***param_values;
  39 };
  40
  41 struct txt_private_data {
  42         struct txt_cache *cache;
  43         uint64_t csn;
  44         bool verbatim;
  45 };
  46
  47 /**********************************************************************
  48  *
  49  * helper functions
  50  *
  51  **********************************************************************/
  52
  53 /**
  54  * a convenience helper to cast the private data structure
  55  */
  56 static struct txt_private_data *pd(struct smbconf_ctx *ctx)
  57 {
  58         return (struct txt_private_data *)(ctx->data);
  59 }
  60
  61 static bool smbconf_txt_do_section(const char *section, void *private_data)
  62 {
  63         sbcErr err;
  64         uint32_t idx;
  65         struct txt_private_data *tpd = (struct txt_private_data *)private_data;
  66         struct txt_cache *cache = tpd->cache;
  67
  68         if (smbconf_find_in_array(section, cache->share_names,
  69                                   cache->num_shares, &idx))
  70         {
  71                 cache->current_share = idx;
  72                 return true;
  73         }
  74
  75         err = smbconf_add_string_to_array(cache, &(cache->share_names),
  76                                           cache->num_shares, section);
  77         if (!SBC_ERROR_IS_OK(err)) {
  78                 return false;
  79         }
  80         cache->current_share = cache->num_shares;
  81         cache->num_shares++;
  82
  83         cache->param_names = talloc_realloc(cache,
  84                                                   cache->param_names,
  85                                                   char **,
  86                                                   cache->num_shares);
  87         if (cache->param_names == NULL) {
  88                 return false;
  89         }
  90         cache->param_names[cache->current_share] = NULL;
  91
  92         cache->param_values = talloc_realloc(cache,
  93                                                    cache->param_values,
  94                                                    char **,
  95                                                    cache->num_shares);
  96         if (cache->param_values == NULL) {
  97                 return false;
  98         }
  99         cache->param_values[cache->current_share] = NULL;
 100
 101         cache->num_params = talloc_realloc(cache,
 102                                                  cache->num_params,
 103                                                  uint32_t,
 104                                                  cache->num_shares);
 105         if (cache->num_params == NULL) {
 106                 return false;
 107         }
 108         cache->num_params[cache->current_share] = 0;
 109
 110         return true;
 111 }
 112
 113 static bool smbconf_txt_do_parameter(const char *param_name,
 114                                      const char *param_value,
 115                                      void *private_data)
 116 {
 117         sbcErr err;
 118         char **param_names, **param_values;
 119         uint32_t num_params;
 120         uint32_t idx;
 121         struct txt_private_data *tpd = (struct txt_private_data *)private_data;
 122         struct txt_cache *cache = tpd->cache;
 123
 124         if (cache->num_shares == 0) {
 125                 /*
 126                  * not in any share yet,
 127                  * initialize the "empty" section (NULL):
 128                  * parameters without a previous [section] are stored here.
 129                  */
 130                 if (!smbconf_txt_do_section(NULL, private_data)) {
 131                         return false;
 132                 }
 133         }
 134
 135         param_names  = cache->param_names[cache->current_share];
 136         param_values = cache->param_values[cache->current_share];
 137         num_params   = cache->num_params[cache->current_share];
 138
 139         if (!(tpd->verbatim) &&
 140             smbconf_find_in_array(param_name, param_names, num_params, &idx))
 141         {
 142                 talloc_free(param_values[idx]);
 143                 param_values[idx] = talloc_strdup(cache, param_value);
 144                 if (param_values[idx] == NULL) {
 145                         return false;
 146                 }
 147                 return true;
 148         }
 149         err = smbconf_add_string_to_array(cache,
 150                                 &(cache->param_names[cache->current_share]),
 151                                 num_params, param_name);
 152         if (!SBC_ERROR_IS_OK(err)) {
 153                 return false;
 154         }
 155         err = smbconf_add_string_to_array(cache,
 156                                 &(cache->param_values[cache->current_share]),
 157                                 num_params, param_value);
 158         cache->num_params[cache->current_share]++;
 159         return SBC_ERROR_IS_OK(err);
 160 }
 161
 162 static void smbconf_txt_flush_cache(struct smbconf_ctx *ctx)
 163 {
 164         talloc_free(pd(ctx)->cache);
 165         pd(ctx)->cache = NULL;
 166 }
 167
 168 static sbcErr smbconf_txt_init_cache(struct smbconf_ctx *ctx)
 169 {
 170         if (pd(ctx)->cache != NULL) {
 171                 smbconf_txt_flush_cache(ctx);
 172         }
 173
 174         pd(ctx)->cache = talloc_zero(pd(ctx), struct txt_cache);
 175
 176         if (pd(ctx)->cache == NULL) {
 177                 return SBC_ERR_NOMEM;
 178         }
 179
 180         return SBC_ERR_OK;
 181 }
 182
 183 static sbcErr smbconf_txt_load_file(struct smbconf_ctx *ctx)
 184 {
 185         sbcErr err;
 186         uint64_t new_csn;
 187
 188         if (!file_exist(ctx->path)) {
 189                 return SBC_ERR_BADFILE;
 190         }
 191
 192         new_csn = (uint64_t)file_modtime(ctx->path);
 193         if (new_csn == pd(ctx)->csn) {
 194                 return SBC_ERR_OK;
 195         }
 196
 197         err = smbconf_txt_init_cache(ctx);
 198         if (!SBC_ERROR_IS_OK(err)) {
 199                 return err;
 200         }
 201
 202         if (!pm_process(ctx->path, smbconf_txt_do_section,
 203                         smbconf_txt_do_parameter, pd(ctx)))
 204         {
 205                 return SBC_ERR_CAN_NOT_COMPLETE;
 206         }
 207
 208         pd(ctx)->csn = new_csn;
 209
 210         return SBC_ERR_OK;
 211 }
 212
 213
 214 /**********************************************************************
 215  *
 216  * smbconf operations: text backend implementations
 217  *
 218  **********************************************************************/
 219
 220 /**
 221  * initialize the text based smbconf backend
 222  */
 223 static sbcErr smbconf_txt_init(struct smbconf_ctx *ctx, const char *path)
 224 {
 225         if (path == NULL) {
 226                 return SBC_ERR_BADFILE;
 227         }
 228         ctx->path = talloc_strdup(ctx, path);
 229         if (ctx->path == NULL) {
 230                 return SBC_ERR_NOMEM;
 231         }
 232
 233         ctx->data = talloc_zero(ctx, struct txt_private_data);
 234         if (ctx->data == NULL) {
 235                 return SBC_ERR_NOMEM;
 236         }
 237
 238         pd(ctx)->verbatim = true;
 239
 240         return SBC_ERR_OK;
 241 }
 242
 243 static int smbconf_txt_shutdown(struct smbconf_ctx *ctx)
 244 {
 245         return ctx->ops->close_conf(ctx);
 246 }
 247
 248 static bool smbconf_txt_requires_messaging(struct smbconf_ctx *ctx)
 249 {
 250         return false;
 251 }
 252
 253 static bool smbconf_txt_is_writeable(struct smbconf_ctx *ctx)
 254 {
 255         /* no write support in this backend yet... */
 256         return false;
 257 }
 258
 259 static sbcErr smbconf_txt_open(struct smbconf_ctx *ctx)
 260 {
 261         return smbconf_txt_load_file(ctx);
 262 }
 263
 264 static int smbconf_txt_close(struct smbconf_ctx *ctx)
 265 {
 266         smbconf_txt_flush_cache(ctx);
 267         return 0;
 268 }
 269
 270 /**
 271  * Get the change sequence number of the given service/parameter.
 272  * service and parameter strings may be NULL.
 273  */
 274 static void smbconf_txt_get_csn(struct smbconf_ctx *ctx,
 275                                 struct smbconf_csn *csn,
 276                                 const char *service, const char *param)
 277 {
 278         if (csn == NULL) {
 279                 return;
 280         }
 281
 282         csn->csn = (uint64_t)file_modtime(ctx->path);
 283 }
 284
 285 /**
 286  * Drop the whole configuration (restarting empty)
 287  */
 288 static sbcErr smbconf_txt_drop(struct smbconf_ctx *ctx)
 289 {
 290         return SBC_ERR_NOT_SUPPORTED;
 291 }
 292
 293 /**
 294  * get the list of share names defined in the configuration.
 295  */
 296 static sbcErr smbconf_txt_get_share_names(struct smbconf_ctx *ctx,
 297                                           TALLOC_CTX *mem_ctx,
 298                                           uint32_t *num_shares,
 299                                           char ***share_names)
 300 {
 301         uint32_t count;
 302         uint32_t added_count = 0;
 303         TALLOC_CTX *tmp_ctx = NULL;
 304         sbcErr err = SBC_ERR_OK;
 305         char **tmp_share_names = NULL;
 306
 307         if ((num_shares == NULL) || (share_names == NULL)) {
 308                 return SBC_ERR_INVALID_PARAM;
 309         }
 310
 311         err = smbconf_txt_load_file(ctx);
 312         if (!SBC_ERROR_IS_OK(err)) {
 313                 return err;
 314         }
 315
 316         tmp_ctx = talloc_stackframe();
 317
 318         /* make sure "global" is always listed first,
 319          * possibly after NULL section */
 320
 321         if (smbconf_share_exists(ctx, NULL)) {
 322                 err = smbconf_add_string_to_array(tmp_ctx, &tmp_share_names,
 323                                                   0, NULL);
 324                 if (!SBC_ERROR_IS_OK(err)) {
 325                         goto done;
 326                 }
 327                 added_count++;
 328         }
 329
 330         if (smbconf_share_exists(ctx, GLOBAL_NAME)) {
 331                 err = smbconf_add_string_to_array(tmp_ctx, &tmp_share_names,
 332                                                    added_count, GLOBAL_NAME);
 333                 if (!SBC_ERROR_IS_OK(err)) {
 334                         goto done;
 335                 }
 336                 added_count++;
 337         }
 338
 339         for (count = 0; count < pd(ctx)->cache->num_shares; count++) {
 340                 if (strequal(pd(ctx)->cache->share_names[count], GLOBAL_NAME) ||
 341                     (pd(ctx)->cache->share_names[count] == NULL))
 342                 {
 343                         continue;
 344                 }
 345
 346                 err = smbconf_add_string_to_array(tmp_ctx, &tmp_share_names,
 347                                         added_count,
 348                                         pd(ctx)->cache->share_names[count]);
 349                 if (!SBC_ERROR_IS_OK(err)) {
 350                         goto done;
 351                 }
 352                 added_count++;
 353         }
 354
 355         *num_shares = added_count;
 356         if (added_count > 0) {
 357                 *share_names = talloc_move(mem_ctx, &tmp_share_names);
 358         } else {
 359                 *share_names = NULL;
 360         }
 361
 362 done:
 363         talloc_free(tmp_ctx);
 364         return err;
 365 }
 366
 367 /**
 368  * check if a share/service of a given name exists
 369  */
 370 static bool smbconf_txt_share_exists(struct smbconf_ctx *ctx,
 371                                      const char *servicename)
 372 {
 373         sbcErr err;
 374
 375         err = smbconf_txt_load_file(ctx);
 376         if (!SBC_ERROR_IS_OK(err)) {
 377                 return false;
 378         }
 379
 380         return smbconf_find_in_array(servicename,
 381                                      pd(ctx)->cache->share_names,
 382                                      pd(ctx)->cache->num_shares, NULL);
 383 }
 384
 385 /**
 386  * Add a service if it does not already exist
 387  */
 388 static sbcErr smbconf_txt_create_share(struct smbconf_ctx *ctx,
 389                                        const char *servicename)
 390 {
 391         return SBC_ERR_NOT_SUPPORTED;
 392 }
 393
 394 /**
 395  * get a definition of a share (service) from configuration.
 396  */
 397 static sbcErr smbconf_txt_get_share(struct smbconf_ctx *ctx,
 398                                     TALLOC_CTX *mem_ctx,
 399                                     const char *servicename,
 400                                     struct smbconf_service **service)
 401 {
 402         sbcErr err;
 403         uint32_t sidx, count;
 404         bool found;
 405         TALLOC_CTX *tmp_ctx = NULL;
 406         struct smbconf_service *tmp_service = NULL;
 407
 408         err = smbconf_txt_load_file(ctx);
 409         if (!SBC_ERROR_IS_OK(err)) {
 410                 return err;
 411         }
 412
 413         found = smbconf_find_in_array(servicename,
 414                                       pd(ctx)->cache->share_names,
 415                                       pd(ctx)->cache->num_shares,
 416                                       &sidx);
 417         if (!found) {
 418                 return SBC_ERR_NO_SUCH_SERVICE;
 419         }
 420
 421         tmp_ctx = talloc_stackframe();
 422
 423         tmp_service = talloc_zero(tmp_ctx, struct smbconf_service);
 424         if (tmp_service == NULL) {
 425                 err = SBC_ERR_NOMEM;
 426                 goto done;
 427         }
 428
 429         if (servicename != NULL) {
 430                 tmp_service->name = talloc_strdup(tmp_service, servicename);
 431                 if (tmp_service->name == NULL) {
 432                         err = SBC_ERR_NOMEM;
 433                         goto done;
 434                 }
 435         }
 436
 437         for (count = 0; count < pd(ctx)->cache->num_params[sidx]; count++) {
 438                 err = smbconf_add_string_to_array(tmp_service,
 439                                 &(tmp_service->param_names),
 440                                 count,
 441                                 pd(ctx)->cache->param_names[sidx][count]);
 442                 if (!SBC_ERROR_IS_OK(err)) {
 443                         goto done;
 444                 }
 445                 err = smbconf_add_string_to_array(tmp_service,
 446                                 &(tmp_service->param_values),
 447                                 count,
 448                                 pd(ctx)->cache->param_values[sidx][count]);
 449                 if (!SBC_ERROR_IS_OK(err)) {
 450                         goto done;
 451                 }
 452         }
 453
 454         tmp_service->num_params = count;
 455         *service = talloc_move(mem_ctx, &tmp_service);
 456
 457 done:
 458         talloc_free(tmp_ctx);
 459         return err;
 460 }
 461
 462 /**
 463  * delete a service from configuration
 464  */
 465 static sbcErr smbconf_txt_delete_share(struct smbconf_ctx *ctx,
 466                                        const char *servicename)
 467 {
 468         return SBC_ERR_NOT_SUPPORTED;
 469 }
 470
 471 /**
 472  * set a configuration parameter to the value provided.
 473  */
 474 static sbcErr smbconf_txt_set_parameter(struct smbconf_ctx *ctx,
 475                                         const char *service,
 476                                         const char *param,
 477                                         const char *valstr)
 478 {
 479         return SBC_ERR_NOT_SUPPORTED;
 480 }
 481
 482 /**
 483  * get the value of a configuration parameter as a string
 484  */
 485 static sbcErr smbconf_txt_get_parameter(struct smbconf_ctx *ctx,
 486                                         TALLOC_CTX *mem_ctx,
 487                                         const char *service,
 488                                         const char *param,
 489                                         char **valstr)
 490 {
 491         sbcErr err;
 492         bool found;
 493         uint32_t share_index, param_index;
 494
 495         err = smbconf_txt_load_file(ctx);
 496         if (!SBC_ERROR_IS_OK(err)) {
 497                 return err;
 498         }
 499
 500         found = smbconf_find_in_array(service,
 501                                       pd(ctx)->cache->share_names,
 502                                       pd(ctx)->cache->num_shares,
 503                                       &share_index);
 504         if (!found) {
 505                 return SBC_ERR_NO_SUCH_SERVICE;
 506         }
 507
 508         found = smbconf_reverse_find_in_array(param,
 509                                 pd(ctx)->cache->param_names[share_index],
 510                                 pd(ctx)->cache->num_params[share_index],
 511                                 &param_index);
 512         if (!found) {
 513                 return SBC_ERR_INVALID_PARAM;
 514         }
 515
 516         *valstr = talloc_strdup(mem_ctx,
 517                         pd(ctx)->cache->param_values[share_index][param_index]);
 518
 519         if (*valstr == NULL) {
 520                 return SBC_ERR_NOMEM;
 521         }
 522
 523         return SBC_ERR_OK;
 524 }
 525
 526 /**
 527  * delete a parameter from configuration
 528  */
 529 static sbcErr smbconf_txt_delete_parameter(struct smbconf_ctx *ctx,
 530                                            const char *service,
 531                                            const char *param)
 532 {
 533         return SBC_ERR_NOT_SUPPORTED;
 534 }
 535
 536 static sbcErr smbconf_txt_get_includes(struct smbconf_ctx *ctx,
 537                                        TALLOC_CTX *mem_ctx,
 538                                        const char *service,
 539                                        uint32_t *num_includes,
 540                                        char ***includes)
 541 {
 542         sbcErr err;
 543         bool found;
 544         uint32_t sidx, count;
 545         TALLOC_CTX *tmp_ctx = NULL;
 546         uint32_t tmp_num_includes = 0;
 547         char **tmp_includes = NULL;
 548
 549         err = smbconf_txt_load_file(ctx);
 550         if (!SBC_ERROR_IS_OK(err)) {
 551                 return err;
 552         }
 553
 554         found = smbconf_find_in_array(service,
 555                                       pd(ctx)->cache->share_names,
 556                                       pd(ctx)->cache->num_shares,
 557                                       &sidx);
 558         if (!found) {
 559                 return SBC_ERR_NO_SUCH_SERVICE;
 560         }
 561
 562         tmp_ctx = talloc_stackframe();
 563
 564         for (count = 0; count < pd(ctx)->cache->num_params[sidx]; count++) {
 565                 if (strequal(pd(ctx)->cache->param_names[sidx][count],
 566                              "include"))
 567                 {
 568                         err = smbconf_add_string_to_array(tmp_ctx,
 569                                 &tmp_includes,
 570                                 tmp_num_includes,
 571                                 pd(ctx)->cache->param_values[sidx][count]);
 572                         if (!SBC_ERROR_IS_OK(err)) {
 573                                 goto done;
 574                         }
 575                         tmp_num_includes++;
 576                 }
 577         }
 578
 579         *num_includes = tmp_num_includes;
 580         if (*num_includes > 0) {
 581                 *includes = talloc_move(mem_ctx, &tmp_includes);
 582                 if (*includes == NULL) {
 583                         err = SBC_ERR_NOMEM;
 584                         goto done;
 585                 }
 586         } else {
 587                 *includes = NULL;
 588         }
 589
 590         err = SBC_ERR_OK;
 591
 592 done:
 593         talloc_free(tmp_ctx);
 594         return err;
 595 }
 596
 597 static sbcErr smbconf_txt_set_includes(struct smbconf_ctx *ctx,
 598                                        const char *service,
 599                                        uint32_t num_includes,
 600                                        const char **includes)
 601 {
 602         return SBC_ERR_NOT_SUPPORTED;
 603 }
 604
 605 static sbcErr smbconf_txt_delete_includes(struct smbconf_ctx *ctx,
 606                                           const char *service)
 607 {
 608         return SBC_ERR_NOT_SUPPORTED;
 609 }
 610
 611 static sbcErr smbconf_txt_transaction_start(struct smbconf_ctx *ctx)
 612 {
 613         return SBC_ERR_OK;
 614 }
 615
 616 static sbcErr smbconf_txt_transaction_commit(struct smbconf_ctx *ctx)
 617 {
 618         return SBC_ERR_OK;
 619 }
 620
 621 static sbcErr smbconf_txt_transaction_cancel(struct smbconf_ctx *ctx)
 622 {
 623         return SBC_ERR_OK;
 624 }
 625
 626 static struct smbconf_ops smbconf_ops_txt = {
 627         .init                   = smbconf_txt_init,
 628         .shutdown               = smbconf_txt_shutdown,
 629         .requires_messaging     = smbconf_txt_requires_messaging,
 630         .is_writeable           = smbconf_txt_is_writeable,
 631         .open_conf              = smbconf_txt_open,
 632         .close_conf             = smbconf_txt_close,
 633         .get_csn                = smbconf_txt_get_csn,
 634         .drop                   = smbconf_txt_drop,
 635         .get_share_names        = smbconf_txt_get_share_names,
 636         .share_exists           = smbconf_txt_share_exists,
 637         .create_share           = smbconf_txt_create_share,
 638         .get_share              = smbconf_txt_get_share,
 639         .delete_share           = smbconf_txt_delete_share,
 640         .set_parameter          = smbconf_txt_set_parameter,
 641         .get_parameter          = smbconf_txt_get_parameter,
 642         .delete_parameter       = smbconf_txt_delete_parameter,
 643         .get_includes           = smbconf_txt_get_includes,
 644         .set_includes           = smbconf_txt_set_includes,
 645         .delete_includes        = smbconf_txt_delete_includes,
 646         .transaction_start      = smbconf_txt_transaction_start,
 647         .transaction_commit     = smbconf_txt_transaction_commit,
 648         .transaction_cancel     = smbconf_txt_transaction_cancel,
 649 };
 650
 651
 652 /**
 653  * initialize the smbconf text backend
 654  * the only function that is exported from this module
 655  */
 656 sbcErr smbconf_init_txt(TALLOC_CTX *mem_ctx,
 657                         struct smbconf_ctx **conf_ctx,
 658                         const char *path)
 659 {
 660         sbcErr err;
 661
 662         err = smbconf_init_internal(mem_ctx, conf_ctx, path, &smbconf_ops_txt);
 663         if (!SBC_ERROR_IS_OK(err)) {
 664                 return err;
 665         }
 666
 667         return smbconf_txt_load_file(*conf_ctx);
 668 }