source3/winbindd/winbindd_cred_cache.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Winbind daemon - krb5 credential cache functions
   5    and in-memory cache functions.
   6
   7    Copyright (C) Guenther Deschner 2005-2006
   8    Copyright (C) Jeremy Allison 2006
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "winbindd.h"
  26 #undef DBGC_CLASS
  27 #define DBGC_CLASS DBGC_WINBIND
  28
  29 /* uncomment this to do fast debugging on the krb5 ticket renewal event */
  30 #ifdef DEBUG_KRB5_TKT_RENEWAL
  31 #undef DEBUG_KRB5_TKT_RENEWAL
  32 #endif
  33
  34 #define MAX_CCACHES 100
  35
  36 static struct WINBINDD_CCACHE_ENTRY *ccache_list;
  37 static void krb5_ticket_gain_handler(struct event_context *,
  38                                      struct timed_event *,
  39                                      struct timeval,
  40                                      void *);
  41
  42 /* The Krb5 ticket refresh handler should be scheduled
  43    at one-half of the period from now till the tkt
  44    expiration */
  45 #define KRB5_EVENT_REFRESH_TIME(x) ((x) - (((x) - time(NULL))/2))
  46
  47 /****************************************************************
  48  Find an entry by name.
  49 ****************************************************************/
  50
  51 static struct WINBINDD_CCACHE_ENTRY *get_ccache_by_username(const char *username)
  52 {
  53         struct WINBINDD_CCACHE_ENTRY *entry;
  54
  55         for (entry = ccache_list; entry; entry = entry->next) {
  56                 if (strequal(entry->username, username)) {
  57                         return entry;
  58                 }
  59         }
  60         return NULL;
  61 }
  62
  63 /****************************************************************
  64  How many do we have ?
  65 ****************************************************************/
  66
  67 static int ccache_entry_count(void)
  68 {
  69         struct WINBINDD_CCACHE_ENTRY *entry;
  70         int i = 0;
  71
  72         for (entry = ccache_list; entry; entry = entry->next) {
  73                 i++;
  74         }
  75         return i;
  76 }
  77
  78 void ccache_remove_all_after_fork(void)
  79 {
  80         struct WINBINDD_CCACHE_ENTRY *cur, *next;
  81
  82         for (cur = ccache_list; cur; cur = next) {
  83                 next = cur->next;
  84                 DLIST_REMOVE(ccache_list, cur);
  85                 TALLOC_FREE(cur->event);
  86                 TALLOC_FREE(cur);
  87         }
  88
  89         return;
  90 }
  91
  92 /****************************************************************
  93  Do the work of refreshing the ticket.
  94 ****************************************************************/
  95
  96 static void krb5_ticket_refresh_handler(struct event_context *event_ctx,
  97                                         struct timed_event *te,
  98                                         struct timeval now,
  99                                         void *private_data)
 100 {
 101         struct WINBINDD_CCACHE_ENTRY *entry =
 102                 talloc_get_type_abort(private_data, struct WINBINDD_CCACHE_ENTRY);
 103 #ifdef HAVE_KRB5
 104         int ret;
 105         time_t new_start;
 106         time_t expire_time = 0;
 107         struct WINBINDD_MEMORY_CREDS *cred_ptr = entry->cred_ptr;
 108 #endif
 109
 110         DEBUG(10,("krb5_ticket_refresh_handler called\n"));
 111         DEBUGADD(10,("event called for: %s, %s\n",
 112                 entry->ccname, entry->username));
 113
 114         TALLOC_FREE(entry->event);
 115
 116 #ifdef HAVE_KRB5
 117
 118         /* Kinit again if we have the user password and we can't renew the old
 119          * tgt anymore
 120          * NB
 121          * This happens when machine are put to sleep for a very long time. */
 122
 123         if (entry->renew_until < time(NULL)) {
 124 rekinit:
 125                 if (cred_ptr && cred_ptr->pass) {
 126
 127                         set_effective_uid(entry->uid);
 128
 129                         ret = kerberos_kinit_password_ext(entry->principal_name,
 130                                                           cred_ptr->pass,
 131                                                           0, /* hm, can we do time correction here ? */
 132                                                           &entry->refresh_time,
 133                                                           &entry->renew_until,
 134                                                           entry->ccname,
 135                                                           False, /* no PAC required anymore */
 136                                                           True,
 137                                                           WINBINDD_PAM_AUTH_KRB5_RENEW_TIME,
 138                                                           NULL);
 139                         gain_root_privilege();
 140
 141                         if (ret) {
 142                                 DEBUG(3,("krb5_ticket_refresh_handler: "
 143                                         "could not re-kinit: %s\n",
 144                                         error_message(ret)));
 145                                 /* destroy the ticket because we cannot rekinit
 146                                  * it, ignore error here */
 147                                 ads_kdestroy(entry->ccname);
 148
 149                                 /* Don't break the ticket refresh chain: retry
 150                                  * refreshing ticket sometime later when KDC is
 151                                  * unreachable -- BoYang
 152                                  * */
 153
 154                                 if ((ret == KRB5_KDC_UNREACH)
 155                                     || (ret == KRB5_REALM_CANT_RESOLVE)) {
 156 #if defined(DEBUG_KRB5_TKT_RENEWAL)
 157                                         new_start = time(NULL) + 30;
 158 #else
 159                                         new_start = time(NULL) +
 160                                                     MAX(30, lp_winbind_cache_time());
 161 #endif
 162                                         /* try to regain ticket here */
 163                                         entry->event = event_add_timed(winbind_event_context(),
 164                                                                        entry,
 165                                                                        timeval_set(new_start, 0),
 166                                                                        krb5_ticket_gain_handler,
 167                                                                        entry);
 168                                         return;
 169                                 }
 170                                 TALLOC_FREE(entry->event);
 171                                 return;
 172                         }
 173
 174                         DEBUG(10,("krb5_ticket_refresh_handler: successful re-kinit "
 175                                 "for: %s in ccache: %s\n",
 176                                 entry->principal_name, entry->ccname));
 177
 178 #if defined(DEBUG_KRB5_TKT_RENEWAL)
 179                         new_start = time(NULL) + 30;
 180 #else
 181                         /* The tkt should be refreshed at one-half the period
 182                            from now to the expiration time */
 183                         expire_time = entry->refresh_time;
 184                         new_start = KRB5_EVENT_REFRESH_TIME(entry->refresh_time);
 185 #endif
 186                         goto done;
 187                 } else {
 188                                 /* can this happen?
 189                                  * No cached credentials
 190                                  * destroy ticket and refresh chain
 191                                  * */
 192                                 ads_kdestroy(entry->ccname);
 193                                 TALLOC_FREE(entry->event);
 194                                 return;
 195                 }
 196         }
 197
 198         set_effective_uid(entry->uid);
 199
 200         ret = smb_krb5_renew_ticket(entry->ccname,
 201                                     entry->principal_name,
 202                                     entry->service,
 203                                     &new_start);
 204 #if defined(DEBUG_KRB5_TKT_RENEWAL)
 205         new_start = time(NULL) + 30;
 206 #else
 207         expire_time = new_start;
 208         new_start = KRB5_EVENT_REFRESH_TIME(new_start);
 209 #endif
 210
 211         gain_root_privilege();
 212
 213         if (ret) {
 214                 DEBUG(3,("krb5_ticket_refresh_handler: "
 215                         "could not renew tickets: %s\n",
 216                         error_message(ret)));
 217                 /* maybe we are beyond the renewing window */
 218
 219                 /* evil rises here, we refresh ticket failed,
 220                  * but the ticket might be expired. Therefore,
 221                  * When we refresh ticket failed, destory the
 222                  * ticket */
 223
 224                 ads_kdestroy(entry->ccname);
 225
 226                 /* avoid breaking the renewal chain: retry in
 227                  * lp_winbind_cache_time() seconds when the KDC was not
 228                  * available right now.
 229                  * the return code can be KRB5_REALM_CANT_RESOLVE*/
 230
 231                 if ((ret == KRB5_KDC_UNREACH)
 232                     || (ret == KRB5_REALM_CANT_RESOLVE)) {
 233 #if defined(DEBUG_KRB5_TKT_RENEWAL)
 234                         new_start = time(NULL) + 30;
 235 #else
 236                         new_start = time(NULL) +
 237                                     MAX(30, lp_winbind_cache_time());
 238 #endif
 239                         /* ticket is destroyed here, we have to regain it
 240                          * if it is possible */
 241                         entry->event = event_add_timed(winbind_event_context(),
 242                                                         entry,
 243                                                         timeval_set(new_start, 0),
 244                                                         krb5_ticket_gain_handler,
 245                                                         entry);
 246                         return;
 247                 }
 248
 249                 /* This is evil, if the ticket was already expired.
 250                  * renew ticket function returns KRB5KRB_AP_ERR_TKT_EXPIRED.
 251                  * But there is still a chance that we can rekinit it.
 252                  *
 253                  * This happens when user login in online mode, and then network
 254                  * down or something cause winbind goes offline for a very long time,
 255                  * and then goes online again. ticket expired, renew failed.
 256                  * This happens when machine are put to sleep for a long time,
 257                  * but shorter than entry->renew_util.
 258                  * NB
 259                  * Looks like the KDC is reachable, we want to rekinit as soon as
 260                  * possible instead of waiting some time later. */
 261                 if ((ret == KRB5KRB_AP_ERR_TKT_EXPIRED)
 262                     || (ret == KRB5_FCC_NOFILE)) goto rekinit;
 263
 264                 return;
 265         }
 266
 267 done:
 268         /* in cases that ticket will be unrenewable soon, we don't try to renew ticket
 269          * but try to regain ticket if it is possible */
 270         if (entry->renew_until && expire_time
 271              && (entry->renew_until <= expire_time)) {
 272                 /* try to regain ticket 10 seconds beforre expiration */
 273                 expire_time -= 10;
 274                 entry->event = event_add_timed(winbind_event_context(), entry,
 275                                                 timeval_set(expire_time, 0),
 276                                                 krb5_ticket_gain_handler,
 277                                                 entry);
 278                 return;
 279         }
 280
 281         if (entry->refresh_time == 0) {
 282                 entry->refresh_time = new_start;
 283         }
 284         entry->event = event_add_timed(winbind_event_context(), entry,
 285                                        timeval_set(new_start, 0),
 286                                        krb5_ticket_refresh_handler,
 287                                        entry);
 288
 289 #endif
 290 }
 291
 292 /****************************************************************
 293  Do the work of regaining a ticket when coming from offline auth.
 294 ****************************************************************/
 295
 296 static void krb5_ticket_gain_handler(struct event_context *event_ctx,
 297                                      struct timed_event *te,
 298                                      struct timeval now,
 299                                      void *private_data)
 300 {
 301         struct WINBINDD_CCACHE_ENTRY *entry =
 302                 talloc_get_type_abort(private_data, struct WINBINDD_CCACHE_ENTRY);
 303 #ifdef HAVE_KRB5
 304         int ret;
 305         struct timeval t;
 306         struct WINBINDD_MEMORY_CREDS *cred_ptr = entry->cred_ptr;
 307         struct winbindd_domain *domain = NULL;
 308 #endif
 309
 310         DEBUG(10,("krb5_ticket_gain_handler called\n"));
 311         DEBUGADD(10,("event called for: %s, %s\n",
 312                 entry->ccname, entry->username));
 313
 314         TALLOC_FREE(entry->event);
 315
 316 #ifdef HAVE_KRB5
 317
 318         if (!cred_ptr || !cred_ptr->pass) {
 319                 DEBUG(10,("krb5_ticket_gain_handler: no memory creds\n"));
 320                 return;
 321         }
 322
 323         if ((domain = find_domain_from_name(entry->realm)) == NULL) {
 324                 DEBUG(0,("krb5_ticket_gain_handler: unknown domain\n"));
 325                 return;
 326         }
 327
 328         if (!domain->online) {
 329                 goto retry_later;
 330         }
 331
 332         set_effective_uid(entry->uid);
 333
 334         ret = kerberos_kinit_password_ext(entry->principal_name,
 335                                           cred_ptr->pass,
 336                                           0, /* hm, can we do time correction here ? */
 337                                           &entry->refresh_time,
 338                                           &entry->renew_until,
 339                                           entry->ccname,
 340                                           False, /* no PAC required anymore */
 341                                           True,
 342                                           WINBINDD_PAM_AUTH_KRB5_RENEW_TIME,
 343                                           NULL);
 344         gain_root_privilege();
 345
 346         if (ret) {
 347                 DEBUG(3,("krb5_ticket_gain_handler: "
 348                         "could not kinit: %s\n",
 349                         error_message(ret)));
 350                 /* evil. If we cannot do it, destroy any the __maybe__
 351                  * __existing__ ticket */
 352                 ads_kdestroy(entry->ccname);
 353                 goto retry_later;
 354         }
 355
 356         DEBUG(10,("krb5_ticket_gain_handler: "
 357                 "successful kinit for: %s in ccache: %s\n",
 358                 entry->principal_name, entry->ccname));
 359
 360         goto got_ticket;
 361
 362   retry_later:
 363
 364 #if defined(DEBUG_KRB5_TKT_REGAIN)
 365         t = timeval_set(time(NULL) + 30, 0);
 366 #else
 367         t = timeval_current_ofs(MAX(30, lp_winbind_cache_time()), 0);
 368 #endif
 369
 370         entry->refresh_time = 0;
 371         entry->event = event_add_timed(winbind_event_context(),
 372                                        entry,
 373                                        t,
 374                                        krb5_ticket_gain_handler,
 375                                        entry);
 376
 377         return;
 378
 379   got_ticket:
 380
 381 #if defined(DEBUG_KRB5_TKT_RENEWAL)
 382         t = timeval_set(time(NULL) + 30, 0);
 383 #else
 384         t = timeval_set(KRB5_EVENT_REFRESH_TIME(entry->refresh_time), 0);
 385 #endif
 386
 387         if (entry->refresh_time == 0) {
 388                 entry->refresh_time = t.tv_sec;
 389         }
 390         entry->event = event_add_timed(winbind_event_context(),
 391                                        entry,
 392                                        t,
 393                                        krb5_ticket_refresh_handler,
 394                                        entry);
 395
 396         return;
 397 #endif
 398 }
 399
 400 void ccache_regain_all_now(void)
 401 {
 402         struct WINBINDD_CCACHE_ENTRY *cur;
 403         struct timeval t = timeval_current();
 404
 405         for (cur = ccache_list; cur; cur = cur->next) {
 406                 struct timed_event *new_event;
 407
 408                 /*
 409                  * if refresh_time is 0, we know that the
 410                  * the event has the krb5_ticket_gain_handler
 411                  */
 412                 if (cur->refresh_time == 0) {
 413                         new_event = event_add_timed(winbind_event_context(),
 414                                                     cur,
 415                                                     t,
 416                                                     krb5_ticket_gain_handler,
 417                                                     cur);
 418                 } else {
 419                         new_event = event_add_timed(winbind_event_context(),
 420                                                     cur,
 421                                                     t,
 422                                                     krb5_ticket_refresh_handler,
 423                                                     cur);
 424                 }
 425
 426                 if (!new_event) {
 427                         continue;
 428                 }
 429
 430                 TALLOC_FREE(cur->event);
 431                 cur->event = new_event;
 432         }
 433
 434         return;
 435 }
 436
 437 /****************************************************************
 438  Check if an ccache entry exists.
 439 ****************************************************************/
 440
 441 bool ccache_entry_exists(const char *username)
 442 {
 443         struct WINBINDD_CCACHE_ENTRY *entry = get_ccache_by_username(username);
 444         return (entry != NULL);
 445 }
 446
 447 /****************************************************************
 448  Ensure we're changing the correct entry.
 449 ****************************************************************/
 450
 451 bool ccache_entry_identical(const char *username,
 452                             uid_t uid,
 453                             const char *ccname)
 454 {
 455         struct WINBINDD_CCACHE_ENTRY *entry = get_ccache_by_username(username);
 456
 457         if (!entry) {
 458                 return False;
 459         }
 460
 461         if (entry->uid != uid) {
 462                 DEBUG(0,("cache_entry_identical: uid's differ: %u != %u\n",
 463                         (unsigned int)entry->uid, (unsigned int)uid));
 464                 return False;
 465         }
 466         if (!strcsequal(entry->ccname, ccname)) {
 467                 DEBUG(0,("cache_entry_identical: "
 468                         "ccnames differ: (cache) %s != (client) %s\n",
 469                         entry->ccname, ccname));
 470                 return False;
 471         }
 472         return True;
 473 }
 474
 475 NTSTATUS add_ccache_to_list(const char *princ_name,
 476                             const char *ccname,
 477                             const char *service,
 478                             const char *username,
 479                             const char *realm,
 480                             uid_t uid,
 481                             time_t create_time,
 482                             time_t ticket_end,
 483                             time_t renew_until,
 484                             bool postponed_request)
 485 {
 486         struct WINBINDD_CCACHE_ENTRY *entry = NULL;
 487         struct timeval t;
 488         NTSTATUS ntret;
 489 #ifdef HAVE_KRB5
 490         int ret;
 491 #endif
 492
 493         if ((username == NULL && princ_name == NULL) ||
 494             ccname == NULL || uid < 0) {
 495                 return NT_STATUS_INVALID_PARAMETER;
 496         }
 497
 498         if (ccache_entry_count() + 1 > MAX_CCACHES) {
 499                 DEBUG(10,("add_ccache_to_list: "
 500                         "max number of ccaches reached\n"));
 501                 return NT_STATUS_NO_MORE_ENTRIES;
 502         }
 503
 504         /* If it is cached login, destroy krb5 ticket
 505          * to avoid surprise. */
 506 #ifdef HAVE_KRB5
 507         if (postponed_request) {
 508                 /* ignore KRB5_FCC_NOFILE error here */
 509                 ret = ads_kdestroy(ccname);
 510                 if (ret == KRB5_FCC_NOFILE) {
 511                         ret = 0;
 512                 }
 513                 if (ret) {
 514                         DEBUG(0, ("add_ccache_to_list: failed to destroy "
 515                                    "user krb5 ccache %s with %s\n", ccname,
 516                                    error_message(ret)));
 517                         return krb5_to_nt_status(ret);
 518                 } else {
 519                         DEBUG(10, ("add_ccache_to_list: successfully destroyed "
 520                                    "krb5 ccache %s for user %s\n", ccname,
 521                                    username));
 522                 }
 523         }
 524 #endif
 525
 526         /* Reference count old entries */
 527         entry = get_ccache_by_username(username);
 528         if (entry) {
 529                 /* Check cached entries are identical. */
 530                 if (!ccache_entry_identical(username, uid, ccname)) {
 531                         return NT_STATUS_INVALID_PARAMETER;
 532                 }
 533                 entry->ref_count++;
 534                 DEBUG(10,("add_ccache_to_list: "
 535                         "ref count on entry %s is now %d\n",
 536                         username, entry->ref_count));
 537                 /* FIXME: in this case we still might want to have a krb5 cred
 538                  * event handler created - gd
 539                  * Add ticket refresh handler here */
 540
 541                 if (!lp_winbind_refresh_tickets() || renew_until <= 0) {
 542                         return NT_STATUS_OK;
 543                 }
 544
 545                 if (!entry->event) {
 546                         if (postponed_request) {
 547                                 t = timeval_current_ofs(MAX(30, lp_winbind_cache_time()), 0);
 548                                 entry->event = event_add_timed(winbind_event_context(),
 549                                                                entry,
 550                                                                t,
 551                                                                krb5_ticket_gain_handler,
 552                                                                entry);
 553                         } else {
 554                                 /* Renew at 1/2 the ticket expiration time */
 555 #if defined(DEBUG_KRB5_TKT_RENEWAL)
 556                                 t = timeval_set(time(NULL)+30, 0);
 557 #else
 558                                 t = timeval_set(KRB5_EVENT_REFRESH_TIME(ticket_end), 0);
 559 #endif
 560                                 entry->event = event_add_timed(winbind_event_context(),
 561                                                                entry,
 562                                                                t,
 563                                                                krb5_ticket_refresh_handler,
 564                                                                entry);
 565                         }
 566
 567                         if (!entry->event) {
 568                                 ntret = remove_ccache(username);
 569                                 if (!NT_STATUS_IS_OK(ntret)) {
 570                                         DEBUG(0, ("add_ccache_to_list: Failed to remove krb5 "
 571                                                   "ccache %s for user %s\n", entry->ccname,
 572                                                   entry->username));
 573                                         DEBUG(0, ("add_ccache_to_list: error is %s\n",
 574                                                   nt_errstr(ntret)));
 575                                         return ntret;
 576                                 }
 577                                 return NT_STATUS_NO_MEMORY;
 578                         }
 579
 580                         DEBUG(10,("add_ccache_to_list: added krb5_ticket handler\n"));
 581                 }
 582
 583                 return NT_STATUS_OK;
 584         }
 585
 586         entry = TALLOC_P(NULL, struct WINBINDD_CCACHE_ENTRY);
 587         if (!entry) {
 588                 return NT_STATUS_NO_MEMORY;
 589         }
 590
 591         ZERO_STRUCTP(entry);
 592
 593         if (username) {
 594                 entry->username = talloc_strdup(entry, username);
 595                 if (!entry->username) {
 596                         goto no_mem;
 597                 }
 598         }
 599         if (princ_name) {
 600                 entry->principal_name = talloc_strdup(entry, princ_name);
 601                 if (!entry->principal_name) {
 602                         goto no_mem;
 603                 }
 604         }
 605         if (service) {
 606                 entry->service = talloc_strdup(entry, service);
 607                 if (!entry->service) {
 608                         goto no_mem;
 609                 }
 610         }
 611
 612         entry->ccname = talloc_strdup(entry, ccname);
 613         if (!entry->ccname) {
 614                 goto no_mem;
 615         }
 616
 617         entry->realm = talloc_strdup(entry, realm);
 618         if (!entry->realm) {
 619                 goto no_mem;
 620         }
 621
 622         entry->create_time = create_time;
 623         entry->renew_until = renew_until;
 624         entry->uid = uid;
 625         entry->ref_count = 1;
 626
 627         if (!lp_winbind_refresh_tickets() || renew_until <= 0) {
 628                 goto add_entry;
 629         }
 630
 631         if (postponed_request) {
 632                 t = timeval_current_ofs(MAX(30, lp_winbind_cache_time()), 0);
 633                 entry->refresh_time = 0;
 634                 entry->event = event_add_timed(winbind_event_context(),
 635                                                entry,
 636                                                t,
 637                                                krb5_ticket_gain_handler,
 638                                                entry);
 639         } else {
 640                 /* Renew at 1/2 the ticket expiration time */
 641 #if defined(DEBUG_KRB5_TKT_RENEWAL)
 642                 t = timeval_set(time(NULL)+30, 0);
 643 #else
 644                 t = timeval_set(KRB5_EVENT_REFRESH_TIME(ticket_end), 0);
 645 #endif
 646                 if (entry->refresh_time == 0) {
 647                         entry->refresh_time = t.tv_sec;
 648                 }
 649                 entry->event = event_add_timed(winbind_event_context(),
 650                                                entry,
 651                                                t,
 652                                                krb5_ticket_refresh_handler,
 653                                                entry);
 654         }
 655
 656         if (!entry->event) {
 657                 goto no_mem;
 658         }
 659
 660         DEBUG(10,("add_ccache_to_list: added krb5_ticket handler\n"));
 661
 662  add_entry:
 663
 664         DLIST_ADD(ccache_list, entry);
 665
 666         DEBUG(10,("add_ccache_to_list: "
 667                 "added ccache [%s] for user [%s] to the list\n",
 668                 ccname, username));
 669
 670         return NT_STATUS_OK;
 671
 672  no_mem:
 673
 674         TALLOC_FREE(entry);
 675         return NT_STATUS_NO_MEMORY;
 676 }
 677
 678 /*******************************************************************
 679  Remove a WINBINDD_CCACHE_ENTRY entry and the krb5 ccache if no longer
 680  referenced.
 681  *******************************************************************/
 682
 683 NTSTATUS remove_ccache(const char *username)
 684 {
 685         struct WINBINDD_CCACHE_ENTRY *entry = get_ccache_by_username(username);
 686         NTSTATUS status = NT_STATUS_OK;
 687         #ifdef HAVE_KRB5
 688         krb5_error_code ret;
 689 #endif
 690
 691         if (!entry) {
 692                 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
 693         }
 694
 695         if (entry->ref_count <= 0) {
 696                 DEBUG(0,("remove_ccache: logic error. "
 697                         "ref count for user %s = %d\n",
 698                         username, entry->ref_count));
 699                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 700         }
 701
 702         entry->ref_count--;
 703
 704         if (entry->ref_count > 0) {
 705                 DEBUG(10,("remove_ccache: entry %s ref count now %d\n",
 706                         username, entry->ref_count));
 707                 return NT_STATUS_OK;
 708         }
 709
 710         /* no references any more */
 711
 712         DLIST_REMOVE(ccache_list, entry);
 713         TALLOC_FREE(entry->event); /* unregisters events */
 714
 715 #ifdef HAVE_KRB5
 716         ret = ads_kdestroy(entry->ccname);
 717
 718         /* we ignore the error when there has been no credential cache */
 719         if (ret == KRB5_FCC_NOFILE) {
 720                 ret = 0;
 721         } else if (ret) {
 722                 DEBUG(0,("remove_ccache: "
 723                         "failed to destroy user krb5 ccache %s with: %s\n",
 724                         entry->ccname, error_message(ret)));
 725         } else {
 726                 DEBUG(10,("remove_ccache: "
 727                         "successfully destroyed krb5 ccache %s for user %s\n",
 728                         entry->ccname, username));
 729         }
 730         status = krb5_to_nt_status(ret);
 731 #endif
 732
 733         TALLOC_FREE(entry);
 734         DEBUG(10,("remove_ccache: removed ccache for user %s\n", username));
 735
 736         return status;
 737 }
 738
 739 /*******************************************************************
 740  In memory credentials cache code.
 741 *******************************************************************/
 742
 743 static struct WINBINDD_MEMORY_CREDS *memory_creds_list;
 744
 745 /***********************************************************
 746  Find an entry on the list by name.
 747 ***********************************************************/
 748
 749 struct WINBINDD_MEMORY_CREDS *find_memory_creds_by_name(const char *username)
 750 {
 751         struct WINBINDD_MEMORY_CREDS *p;
 752
 753         for (p = memory_creds_list; p; p = p->next) {
 754                 if (strequal(p->username, username)) {
 755                         return p;
 756                 }
 757         }
 758         return NULL;
 759 }
 760
 761 /***********************************************************
 762  Store the required creds and mlock them.
 763 ***********************************************************/
 764
 765 static NTSTATUS store_memory_creds(struct WINBINDD_MEMORY_CREDS *memcredp,
 766                                    const char *pass)
 767 {
 768 #if !defined(HAVE_MLOCK)
 769         return NT_STATUS_OK;
 770 #else
 771         /* new_entry->nt_hash is the base pointer for the block
 772            of memory pointed into by new_entry->lm_hash and
 773            new_entry->pass (if we're storing plaintext). */
 774
 775         memcredp->len = NT_HASH_LEN + LM_HASH_LEN;
 776         if (pass) {
 777                 memcredp->len += strlen(pass)+1;
 778         }
 779
 780
 781 #if defined(LINUX)
 782         /* aligning the memory on on x86_64 and compiling
 783            with gcc 4.1 using -O2 causes a segv in the
 784            next memset()  --jerry */
 785         memcredp->nt_hash = SMB_MALLOC_ARRAY(unsigned char, memcredp->len);
 786 #else
 787         /* On non-linux platforms, mlock()'d memory must be aligned */
 788         memcredp->nt_hash = SMB_MEMALIGN_ARRAY(unsigned char,
 789                                                getpagesize(), memcredp->len);
 790 #endif
 791         if (!memcredp->nt_hash) {
 792                 return NT_STATUS_NO_MEMORY;
 793         }
 794         memset(memcredp->nt_hash, 0x0, memcredp->len);
 795
 796         memcredp->lm_hash = memcredp->nt_hash + NT_HASH_LEN;
 797
 798 #ifdef DEBUG_PASSWORD
 799         DEBUG(10,("mlocking memory: %p\n", memcredp->nt_hash));
 800 #endif
 801         if ((mlock(memcredp->nt_hash, memcredp->len)) == -1) {
 802                 DEBUG(0,("failed to mlock memory: %s (%d)\n",
 803                         strerror(errno), errno));
 804                 SAFE_FREE(memcredp->nt_hash);
 805                 return map_nt_error_from_unix(errno);
 806         }
 807
 808 #ifdef DEBUG_PASSWORD
 809         DEBUG(10,("mlocked memory: %p\n", memcredp->nt_hash));
 810 #endif
 811
 812         /* Create and store the password hashes. */
 813         E_md4hash(pass, memcredp->nt_hash);
 814         E_deshash(pass, memcredp->lm_hash);
 815
 816         if (pass) {
 817                 memcredp->pass = (char *)memcredp->lm_hash + LM_HASH_LEN;
 818                 memcpy(memcredp->pass, pass,
 819                        memcredp->len - NT_HASH_LEN - LM_HASH_LEN);
 820         }
 821
 822         return NT_STATUS_OK;
 823 #endif
 824 }
 825
 826 /***********************************************************
 827  Destroy existing creds.
 828 ***********************************************************/
 829
 830 static NTSTATUS delete_memory_creds(struct WINBINDD_MEMORY_CREDS *memcredp)
 831 {
 832 #if !defined(HAVE_MUNLOCK)
 833         return NT_STATUS_OK;
 834 #else
 835         if (munlock(memcredp->nt_hash, memcredp->len) == -1) {
 836                 DEBUG(0,("failed to munlock memory: %s (%d)\n",
 837                         strerror(errno), errno));
 838                 return map_nt_error_from_unix(errno);
 839         }
 840         memset(memcredp->nt_hash, '\0', memcredp->len);
 841         SAFE_FREE(memcredp->nt_hash);
 842         memcredp->nt_hash = NULL;
 843         memcredp->lm_hash = NULL;
 844         memcredp->pass = NULL;
 845         memcredp->len = 0;
 846         return NT_STATUS_OK;
 847 #endif
 848 }
 849
 850 /***********************************************************
 851  Replace the required creds with new ones (password change).
 852 ***********************************************************/
 853
 854 static NTSTATUS winbindd_replace_memory_creds_internal(struct WINBINDD_MEMORY_CREDS *memcredp,
 855                                                        const char *pass)
 856 {
 857         NTSTATUS status = delete_memory_creds(memcredp);
 858         if (!NT_STATUS_IS_OK(status)) {
 859                 return status;
 860         }
 861         return store_memory_creds(memcredp, pass);
 862 }
 863
 864 /*************************************************************
 865  Store credentials in memory in a list.
 866 *************************************************************/
 867
 868 static NTSTATUS winbindd_add_memory_creds_internal(const char *username,
 869                                                    uid_t uid,
 870                                                    const char *pass)
 871 {
 872         /* Shortcut to ensure we don't store if no mlock. */
 873 #if !defined(HAVE_MLOCK) || !defined(HAVE_MUNLOCK)
 874         return NT_STATUS_OK;
 875 #else
 876         NTSTATUS status;
 877         struct WINBINDD_MEMORY_CREDS *memcredp = NULL;
 878
 879         memcredp = find_memory_creds_by_name(username);
 880         if (uid == (uid_t)-1) {
 881                 DEBUG(0,("winbindd_add_memory_creds_internal: "
 882                         "invalid uid for user %s.\n", username));
 883                 return NT_STATUS_INVALID_PARAMETER;
 884         }
 885
 886         if (memcredp) {
 887                 /* Already exists. Increment the reference count and replace stored creds. */
 888                 if (uid != memcredp->uid) {
 889                         DEBUG(0,("winbindd_add_memory_creds_internal: "
 890                                 "uid %u for user %s doesn't "
 891                                 "match stored uid %u. Replacing.\n",
 892                                 (unsigned int)uid, username,
 893                                 (unsigned int)memcredp->uid));
 894                         memcredp->uid = uid;
 895                 }
 896                 memcredp->ref_count++;
 897                 DEBUG(10,("winbindd_add_memory_creds_internal: "
 898                         "ref count for user %s is now %d\n",
 899                         username, memcredp->ref_count));
 900                 return winbindd_replace_memory_creds_internal(memcredp, pass);
 901         }
 902
 903         memcredp = TALLOC_ZERO_P(NULL, struct WINBINDD_MEMORY_CREDS);
 904         if (!memcredp) {
 905                 return NT_STATUS_NO_MEMORY;
 906         }
 907         memcredp->username = talloc_strdup(memcredp, username);
 908         if (!memcredp->username) {
 909                 talloc_destroy(memcredp);
 910                 return NT_STATUS_NO_MEMORY;
 911         }
 912
 913         status = store_memory_creds(memcredp, pass);
 914         if (!NT_STATUS_IS_OK(status)) {
 915                 talloc_destroy(memcredp);
 916                 return status;
 917         }
 918
 919         memcredp->uid = uid;
 920         memcredp->ref_count = 1;
 921         DLIST_ADD(memory_creds_list, memcredp);
 922
 923         DEBUG(10,("winbindd_add_memory_creds_internal: "
 924                 "added entry for user %s\n", username));
 925
 926         return NT_STATUS_OK;
 927 #endif
 928 }
 929
 930 /*************************************************************
 931  Store users credentials in memory. If we also have a
 932  struct WINBINDD_CCACHE_ENTRY for this username with a
 933  refresh timer, then store the plaintext of the password
 934  and associate the new credentials with the struct WINBINDD_CCACHE_ENTRY.
 935 *************************************************************/
 936
 937 NTSTATUS winbindd_add_memory_creds(const char *username,
 938                                    uid_t uid,
 939                                    const char *pass)
 940 {
 941         struct WINBINDD_CCACHE_ENTRY *entry = get_ccache_by_username(username);
 942         NTSTATUS status;
 943
 944         status = winbindd_add_memory_creds_internal(username, uid, pass);
 945         if (!NT_STATUS_IS_OK(status)) {
 946                 return status;
 947         }
 948
 949         if (entry) {
 950                 struct WINBINDD_MEMORY_CREDS *memcredp = NULL;
 951                 memcredp = find_memory_creds_by_name(username);
 952                 if (memcredp) {
 953                         entry->cred_ptr = memcredp;
 954                 }
 955         }
 956
 957         return status;
 958 }
 959
 960 /*************************************************************
 961  Decrement the in-memory ref count - delete if zero.
 962 *************************************************************/
 963
 964 NTSTATUS winbindd_delete_memory_creds(const char *username)
 965 {
 966         struct WINBINDD_MEMORY_CREDS *memcredp = NULL;
 967         struct WINBINDD_CCACHE_ENTRY *entry = NULL;
 968         NTSTATUS status = NT_STATUS_OK;
 969
 970         memcredp = find_memory_creds_by_name(username);
 971         entry = get_ccache_by_username(username);
 972
 973         if (!memcredp) {
 974                 DEBUG(10,("winbindd_delete_memory_creds: unknown user %s\n",
 975                         username));
 976                 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
 977         }
 978
 979         if (memcredp->ref_count <= 0) {
 980                 DEBUG(0,("winbindd_delete_memory_creds: logic error. "
 981                         "ref count for user %s = %d\n",
 982                         username, memcredp->ref_count));
 983                 status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 984         }
 985
 986         memcredp->ref_count--;
 987         if (memcredp->ref_count <= 0) {
 988                 delete_memory_creds(memcredp);
 989                 DLIST_REMOVE(memory_creds_list, memcredp);
 990                 talloc_destroy(memcredp);
 991                 DEBUG(10,("winbindd_delete_memory_creds: "
 992                         "deleted entry for user %s\n",
 993                         username));
 994         } else {
 995                 DEBUG(10,("winbindd_delete_memory_creds: "
 996                         "entry for user %s ref_count now %d\n",
 997                         username, memcredp->ref_count));
 998         }
 999
1000         if (entry) {
1001                 /* Ensure we have no dangling references to this. */
1002                 entry->cred_ptr = NULL;
1003         }
1004
1005         return status;
1006 }
1007
1008 /***********************************************************
1009  Replace the required creds with new ones (password change).
1010 ***********************************************************/
1011
1012 NTSTATUS winbindd_replace_memory_creds(const char *username,
1013                                        const char *pass)
1014 {
1015         struct WINBINDD_MEMORY_CREDS *memcredp = NULL;
1016
1017         memcredp = find_memory_creds_by_name(username);
1018         if (!memcredp) {
1019                 DEBUG(10,("winbindd_replace_memory_creds: unknown user %s\n",
1020                         username));
1021                 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
1022         }
1023
1024         DEBUG(10,("winbindd_replace_memory_creds: replaced creds for user %s\n",
1025                 username));
1026
1027         return winbindd_replace_memory_creds_internal(memcredp, pass);
1028 }