source3/libads/kerberos_keytab.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    kerberos keytab utility library
   4    Copyright (C) Andrew Tridgell 2001
   5    Copyright (C) Remus Koos 2001
   6    Copyright (C) Luke Howard 2003
   7    Copyright (C) Jim McDonough (jmcd@us.ibm.com) 2003
   8    Copyright (C) Guenther Deschner 2003
   9    Copyright (C) Rakesh Patel 2004
  10    Copyright (C) Dan Perry 2004
  11    Copyright (C) Jeremy Allison 2004
  12    Copyright (C) Gerald Carter 2006
  13
  14    This program is free software; you can redistribute it and/or modify
  15    it under the terms of the GNU General Public License as published by
  16    the Free Software Foundation; either version 3 of the License, or
  17    (at your option) any later version.
  18
  19    This program is distributed in the hope that it will be useful,
  20    but WITHOUT ANY WARRANTY; without even the implied warranty of
  21    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22    GNU General Public License for more details.
  23
  24    You should have received a copy of the GNU General Public License
  25    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  26 */
  27
  28 #include "includes.h"
  29 #include "smb_krb5.h"
  30 #include "ads.h"
  31 #include "secrets.h"
  32
  33 #ifdef HAVE_KRB5
  34
  35 /**********************************************************************
  36 **********************************************************************/
  37
  38 static krb5_error_code seek_and_delete_old_entries(krb5_context context,
  39                                                    krb5_keytab keytab,
  40                                                    krb5_kvno kvno,
  41                                                    const char *princ_s,
  42                                                    krb5_principal princ,
  43                                                    bool flush,
  44                                                    bool keep_old_entries)
  45 {
  46         krb5_error_code ret;
  47         krb5_kt_cursor cursor;
  48         krb5_kt_cursor zero_csr;
  49         krb5_keytab_entry kt_entry;
  50         krb5_keytab_entry zero_kt_entry;
  51         char *ktprinc = NULL;
  52
  53         ZERO_STRUCT(cursor);
  54         ZERO_STRUCT(zero_csr);
  55         ZERO_STRUCT(kt_entry);
  56         ZERO_STRUCT(zero_kt_entry);
  57
  58         ret = krb5_kt_start_seq_get(context, keytab, &cursor);
  59         if (ret == KRB5_KT_END || ret == ENOENT ) {
  60                 /* no entries */
  61                 return 0;
  62         }
  63
  64         DEBUG(3, (__location__ ": Will try to delete old keytab entries\n"));
  65         while (!krb5_kt_next_entry(context, keytab, &kt_entry, &cursor)) {
  66                 bool name_ok = False;
  67
  68                 if (!flush && (princ_s != NULL)) {
  69                         ret = smb_krb5_unparse_name(talloc_tos(), context,
  70                                                     kt_entry.principal,
  71                                                     &ktprinc);
  72                         if (ret) {
  73                                 DEBUG(1, (__location__
  74                                           ": smb_krb5_unparse_name failed "
  75                                           "(%s)\n", error_message(ret)));
  76                                 goto out;
  77                         }
  78
  79 #ifdef HAVE_KRB5_KT_COMPARE
  80                         name_ok = krb5_kt_compare(context, &kt_entry,
  81                                                   princ, 0, 0);
  82 #else
  83                         name_ok = (strcmp(ktprinc, princ_s) == 0);
  84 #endif
  85
  86                         if (!name_ok) {
  87                                 DEBUG(10, (__location__ ": ignoring keytab "
  88                                            "entry principal %s, kvno = %d\n",
  89                                            ktprinc, kt_entry.vno));
  90
  91                                 /* Not a match,
  92                                  * just free this entry and continue. */
  93                                 ret = smb_krb5_kt_free_entry(context,
  94                                                              &kt_entry);
  95                                 ZERO_STRUCT(kt_entry);
  96                                 if (ret) {
  97                                         DEBUG(1, (__location__
  98                                                   ": smb_krb5_kt_free_entry "
  99                                                   "failed (%s)\n",
 100                                                   error_message(ret)));
 101                                         goto out;
 102                                 }
 103
 104                                 TALLOC_FREE(ktprinc);
 105                                 continue;
 106                         }
 107
 108                         TALLOC_FREE(ktprinc);
 109                 }
 110
 111                 /*------------------------------------------------------------
 112                  * Save the entries with kvno - 1. This is what microsoft does
 113                  * to allow people with existing sessions that have kvno - 1
 114                  * to still work. Otherwise, when the password for the machine
 115                  * changes, all kerberizied sessions will 'break' until either
 116                  * the client reboots or the client's session key expires and
 117                  * they get a new session ticket with the new kvno.
 118                  */
 119
 120                 if (!flush && (kt_entry.vno == kvno - 1)) {
 121                         DEBUG(5, (__location__ ": Saving previous (kvno %d) "
 122                                   "entry for principal: %s.\n",
 123                                   kvno - 1, princ_s));
 124                         continue;
 125                 }
 126
 127                 if (keep_old_entries) {
 128                         DEBUG(5, (__location__ ": Saving old (kvno %d) "
 129                                   "entry for principal: %s.\n",
 130                                   kvno, princ_s));
 131                         continue;
 132                 }
 133
 134                 DEBUG(5, (__location__ ": Found old entry for principal: %s "
 135                           "(kvno %d) - trying to remove it.\n",
 136                           princ_s, kt_entry.vno));
 137
 138                 ret = krb5_kt_end_seq_get(context, keytab, &cursor);
 139                 ZERO_STRUCT(cursor);
 140                 if (ret) {
 141                         DEBUG(1, (__location__ ": krb5_kt_end_seq_get() "
 142                                   "failed (%s)\n", error_message(ret)));
 143                         goto out;
 144                 }
 145                 ret = krb5_kt_remove_entry(context, keytab, &kt_entry);
 146                 if (ret) {
 147                         DEBUG(1, (__location__ ": krb5_kt_remove_entry() "
 148                                   "failed (%s)\n", error_message(ret)));
 149                         goto out;
 150                 }
 151
 152                 DEBUG(5, (__location__ ": removed old entry for principal: "
 153                           "%s (kvno %d).\n", princ_s, kt_entry.vno));
 154
 155                 ret = krb5_kt_start_seq_get(context, keytab, &cursor);
 156                 if (ret) {
 157                         DEBUG(1, (__location__ ": krb5_kt_start_seq() failed "
 158                                   "(%s)\n", error_message(ret)));
 159                         goto out;
 160                 }
 161                 ret = smb_krb5_kt_free_entry(context, &kt_entry);
 162                 ZERO_STRUCT(kt_entry);
 163                 if (ret) {
 164                         DEBUG(1, (__location__ ": krb5_kt_remove_entry() "
 165                                   "failed (%s)\n", error_message(ret)));
 166                         goto out;
 167                 }
 168         }
 169
 170 out:
 171         if (memcmp(&zero_kt_entry, &kt_entry, sizeof(krb5_keytab_entry))) {
 172                 smb_krb5_kt_free_entry(context, &kt_entry);
 173         }
 174         if (keytab) {
 175                 if (memcmp(&cursor, &zero_csr, sizeof(krb5_kt_cursor)) != 0) {
 176                         krb5_kt_end_seq_get(context, keytab, &cursor);
 177                 }
 178         }
 179
 180         return ret;
 181 }
 182
 183 static int smb_krb5_kt_add_entry(krb5_context context,
 184                                  krb5_keytab keytab,
 185                                  krb5_kvno kvno,
 186                                  const char *princ_s,
 187                                  krb5_enctype *enctypes,
 188                                  krb5_data password,
 189                                  bool no_salt,
 190                                  bool keep_old_entries)
 191 {
 192         krb5_error_code ret;
 193         krb5_keytab_entry kt_entry;
 194         krb5_principal princ = NULL;
 195         int i;
 196
 197         ZERO_STRUCT(kt_entry);
 198
 199         ret = smb_krb5_parse_name(context, princ_s, &princ);
 200         if (ret) {
 201                 DEBUG(1, (__location__ ": smb_krb5_parse_name(%s) "
 202                           "failed (%s)\n", princ_s, error_message(ret)));
 203                 goto out;
 204         }
 205
 206         /* Seek and delete old keytab entries */
 207         ret = seek_and_delete_old_entries(context, keytab, kvno,
 208                                           princ_s, princ, false,
 209                                           keep_old_entries);
 210         if (ret) {
 211                 goto out;
 212         }
 213
 214         /* If we get here, we have deleted all the old entries with kvno's
 215          * not equal to the current kvno-1. */
 216
 217         /* Now add keytab entries for all encryption types */
 218         for (i = 0; enctypes[i]; i++) {
 219                 krb5_keyblock *keyp;
 220
 221                 keyp = KRB5_KT_KEY(&kt_entry);
 222
 223                 if (create_kerberos_key_from_string(context, princ,
 224                                                     &password, keyp,
 225                                                     enctypes[i], no_salt)) {
 226                         continue;
 227                 }
 228
 229                 kt_entry.principal = princ;
 230                 kt_entry.vno       = kvno;
 231
 232                 DEBUG(3, (__location__ ": adding keytab entry for (%s) with "
 233                           "encryption type (%d) and version (%d)\n",
 234                           princ_s, enctypes[i], kt_entry.vno));
 235                 ret = krb5_kt_add_entry(context, keytab, &kt_entry);
 236                 krb5_free_keyblock_contents(context, keyp);
 237                 ZERO_STRUCT(kt_entry);
 238                 if (ret) {
 239                         DEBUG(1, (__location__ ": adding entry to keytab "
 240                                   "failed (%s)\n", error_message(ret)));
 241                         goto out;
 242                 }
 243         }
 244
 245 out:
 246         if (princ) {
 247                 krb5_free_principal(context, princ);
 248         }
 249
 250         return (int)ret;
 251 }
 252
 253 #ifdef HAVE_ADS
 254
 255 /**********************************************************************
 256  Adds a single service principal, i.e. 'host' to the system keytab
 257 ***********************************************************************/
 258
 259 int ads_keytab_add_entry(ADS_STRUCT *ads, const char *srvPrinc)
 260 {
 261         krb5_error_code ret = 0;
 262         krb5_context context = NULL;
 263         krb5_keytab keytab = NULL;
 264         krb5_data password;
 265         krb5_kvno kvno;
 266         krb5_enctype enctypes[6] = {
 267                 ENCTYPE_DES_CBC_CRC,
 268                 ENCTYPE_DES_CBC_MD5,
 269 #ifdef HAVE_ENCTYPE_AES128_CTS_HMAC_SHA1_96
 270                 ENCTYPE_AES128_CTS_HMAC_SHA1_96,
 271 #endif
 272 #ifdef HAVE_ENCTYPE_AES256_CTS_HMAC_SHA1_96
 273                 ENCTYPE_AES256_CTS_HMAC_SHA1_96,
 274 #endif
 275                 ENCTYPE_ARCFOUR_HMAC,
 276                 0
 277         };
 278         char *princ_s = NULL;
 279         char *short_princ_s = NULL;
 280         char *password_s = NULL;
 281         char *my_fqdn;
 282         TALLOC_CTX *tmpctx = NULL;
 283         char *machine_name;
 284         ADS_STATUS aderr;
 285
 286         initialize_krb5_error_table();
 287         ret = krb5_init_context(&context);
 288         if (ret) {
 289                 DEBUG(1, (__location__ ": could not krb5_init_context: %s\n",
 290                           error_message(ret)));
 291                 return -1;
 292         }
 293
 294         ret = smb_krb5_open_keytab(context, NULL, True, &keytab);
 295         if (ret) {
 296                 DEBUG(1, (__location__ ": smb_krb5_open_keytab failed (%s)\n",
 297                           error_message(ret)));
 298                 goto out;
 299         }
 300
 301         /* retrieve the password */
 302         if (!secrets_init()) {
 303                 DEBUG(1, (__location__ ": secrets_init failed\n"));
 304                 ret = -1;
 305                 goto out;
 306         }
 307         password_s = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
 308         if (!password_s) {
 309                 DEBUG(1, (__location__ ": failed to fetch machine password\n"));
 310                 ret = -1;
 311                 goto out;
 312         }
 313         ZERO_STRUCT(password);
 314         password.data = password_s;
 315         password.length = strlen(password_s);
 316
 317         /* we need the dNSHostName value here */
 318         tmpctx = talloc_init(__location__);
 319         if (!tmpctx) {
 320                 DEBUG(0, (__location__ ": talloc_init() failed!\n"));
 321                 ret = -1;
 322                 goto out;
 323         }
 324
 325         my_fqdn = ads_get_dnshostname(ads, tmpctx, lp_netbios_name());
 326         if (!my_fqdn) {
 327                 DEBUG(0, (__location__ ": unable to determine machine "
 328                           "account's dns name in AD!\n"));
 329                 ret = -1;
 330                 goto out;
 331         }
 332
 333         machine_name = ads_get_samaccountname(ads, tmpctx, lp_netbios_name());
 334         if (!machine_name) {
 335                 DEBUG(0, (__location__ ": unable to determine machine "
 336                           "account's short name in AD!\n"));
 337                 ret = -1;
 338                 goto out;
 339         }
 340         /*strip the trailing '$' */
 341         machine_name[strlen(machine_name)-1] = '\0';
 342
 343         /* Construct our principal */
 344         if (strchr_m(srvPrinc, '@')) {
 345                 /* It's a fully-named principal. */
 346                 princ_s = talloc_asprintf(tmpctx, "%s", srvPrinc);
 347                 if (!princ_s) {
 348                         ret = -1;
 349                         goto out;
 350                 }
 351         } else if (srvPrinc[strlen(srvPrinc)-1] == '$') {
 352                 /* It's the machine account, as used by smbclient clients. */
 353                 princ_s = talloc_asprintf(tmpctx, "%s@%s",
 354                                           srvPrinc, lp_realm());
 355                 if (!princ_s) {
 356                         ret = -1;
 357                         goto out;
 358                 }
 359         } else {
 360                 /* It's a normal service principal.  Add the SPN now so that we
 361                  * can obtain credentials for it and double-check the salt value
 362                  * used to generate the service's keys. */
 363
 364                 princ_s = talloc_asprintf(tmpctx, "%s/%s@%s",
 365                                           srvPrinc, my_fqdn, lp_realm());
 366                 if (!princ_s) {
 367                         ret = -1;
 368                         goto out;
 369                 }
 370                 short_princ_s = talloc_asprintf(tmpctx, "%s/%s@%s",
 371                                                 srvPrinc, machine_name,
 372                                                 lp_realm());
 373                 if (short_princ_s == NULL) {
 374                         ret = -1;
 375                         goto out;
 376                 }
 377
 378                 /* According to http://support.microsoft.com/kb/326985/en-us,
 379                    certain principal names are automatically mapped to the
 380                    host/... principal in the AD account.
 381                    So only create these in the keytab, not in AD.  --jerry */
 382
 383                 if (!strequal(srvPrinc, "cifs") &&
 384                     !strequal(srvPrinc, "host")) {
 385                         DEBUG(3, (__location__ ": Attempting to add/update "
 386                                   "'%s'\n", princ_s));
 387
 388                         aderr = ads_add_service_principal_name(ads,
 389                                         lp_netbios_name(), my_fqdn, srvPrinc);
 390                         if (!ADS_ERR_OK(aderr)) {
 391                                 DEBUG(1, (__location__ ": failed to "
 392                                          "ads_add_service_principal_name.\n"));
 393                                 goto out;
 394                         }
 395                 }
 396         }
 397
 398         kvno = (krb5_kvno)ads_get_machine_kvno(ads, lp_netbios_name());
 399         if (kvno == -1) {
 400                 /* -1 indicates failure, everything else is OK */
 401                 DEBUG(1, (__location__ ": ads_get_machine_kvno failed to "
 402                          "determine the system's kvno.\n"));
 403                 ret = -1;
 404                 goto out;
 405         }
 406
 407         /* add the fqdn principal to the keytab */
 408         ret = smb_krb5_kt_add_entry(context, keytab, kvno,
 409                                     princ_s, enctypes, password,
 410                                     false, false);
 411         if (ret) {
 412                 DEBUG(1, (__location__ ": Failed to add entry to keytab\n"));
 413                 goto out;
 414         }
 415
 416         /* add the short principal name if we have one */
 417         if (short_princ_s) {
 418                 ret = smb_krb5_kt_add_entry(context, keytab, kvno,
 419                                             short_princ_s, enctypes, password,
 420                                             false, false);
 421                 if (ret) {
 422                         DEBUG(1, (__location__
 423                                   ": Failed to add short entry to keytab\n"));
 424                         goto out;
 425                 }
 426         }
 427
 428 out:
 429         TALLOC_FREE(tmpctx);
 430
 431         if (keytab) {
 432                 krb5_kt_close(context, keytab);
 433         }
 434         if (context) {
 435                 krb5_free_context(context);
 436         }
 437         return (int)ret;
 438 }
 439
 440 /**********************************************************************
 441  Flushes all entries from the system keytab.
 442 ***********************************************************************/
 443
 444 int ads_keytab_flush(ADS_STRUCT *ads)
 445 {
 446         krb5_error_code ret = 0;
 447         krb5_context context = NULL;
 448         krb5_keytab keytab = NULL;
 449         krb5_kvno kvno;
 450         ADS_STATUS aderr;
 451
 452         initialize_krb5_error_table();
 453         ret = krb5_init_context(&context);
 454         if (ret) {
 455                 DEBUG(1, (__location__ ": could not krb5_init_context: %s\n",
 456                           error_message(ret)));
 457                 return ret;
 458         }
 459
 460         ret = smb_krb5_open_keytab(context, NULL, True, &keytab);
 461         if (ret) {
 462                 DEBUG(1, (__location__ ": smb_krb5_open_keytab failed (%s)\n",
 463                           error_message(ret)));
 464                 goto out;
 465         }
 466
 467         kvno = (krb5_kvno)ads_get_machine_kvno(ads, lp_netbios_name());
 468         if (kvno == -1) {
 469                 /* -1 indicates a failure */
 470                 DEBUG(1, (__location__ ": Error determining the kvno.\n"));
 471                 goto out;
 472         }
 473
 474         /* Seek and delete old keytab entries */
 475         ret = seek_and_delete_old_entries(context, keytab, kvno,
 476                                           NULL, NULL, true, false);
 477         if (ret) {
 478                 goto out;
 479         }
 480
 481         aderr = ads_clear_service_principal_names(ads, lp_netbios_name());
 482         if (!ADS_ERR_OK(aderr)) {
 483                 DEBUG(1, (__location__ ": Error while clearing service "
 484                           "principal listings in LDAP.\n"));
 485                 goto out;
 486         }
 487
 488 out:
 489         if (keytab) {
 490                 krb5_kt_close(context, keytab);
 491         }
 492         if (context) {
 493                 krb5_free_context(context);
 494         }
 495         return ret;
 496 }
 497
 498 /**********************************************************************
 499  Adds all the required service principals to the system keytab.
 500 ***********************************************************************/
 501
 502 int ads_keytab_create_default(ADS_STRUCT *ads)
 503 {
 504         krb5_error_code ret = 0;
 505         krb5_context context = NULL;
 506         krb5_keytab keytab = NULL;
 507         krb5_kt_cursor cursor;
 508         krb5_keytab_entry kt_entry;
 509         krb5_kvno kvno;
 510         size_t found = 0;
 511         char *sam_account_name, *upn;
 512         char **oldEntries = NULL, *princ_s[26];
 513         TALLOC_CTX *frame;
 514         char *machine_name;
 515         char **spn_array;
 516         size_t num_spns;
 517         size_t i;
 518         ADS_STATUS status;
 519
 520         frame = talloc_stackframe();
 521         if (frame == NULL) {
 522                 ret = -1;
 523                 goto done;
 524         }
 525
 526         status = ads_get_service_principal_names(frame,
 527                                                  ads,
 528                                                  lp_netbios_name(),
 529                                                  &spn_array,
 530                                                  &num_spns);
 531         if (!ADS_ERR_OK(status)) {
 532                 ret = -1;
 533                 goto done;
 534         }
 535
 536         for (i = 0; i < num_spns; i++) {
 537                 char *srv_princ;
 538                 char *p;
 539
 540                 srv_princ = strlower_talloc(frame, spn_array[i]);
 541                 if (srv_princ == NULL) {
 542                         ret = -1;
 543                         goto done;
 544                 }
 545
 546                 p = strchr_m(srv_princ, '/');
 547                 if (p == NULL) {
 548                         continue;
 549                 }
 550                 p[0] = '\0';
 551
 552                 /* Add the SPNs found on the DC */
 553                 ret = ads_keytab_add_entry(ads, srv_princ);
 554                 if (ret != 0) {
 555                         DEBUG(1, ("ads_keytab_add_entry failed while "
 556                                   "adding '%s' principal.\n",
 557                                   spn_array[i]));
 558                         goto done;
 559                 }
 560         }
 561
 562 #if 0   /* don't create the CIFS/... keytab entries since no one except smbd
 563            really needs them and we will fall back to verifying against
 564            secrets.tdb */
 565
 566         ret = ads_keytab_add_entry(ads, "cifs"));
 567         if (ret != 0 ) {
 568                 DEBUG(1, (__location__ ": ads_keytab_add_entry failed while "
 569                           "adding 'cifs'.\n"));
 570                 return ret;
 571         }
 572 #endif
 573
 574         memset(princ_s, '\0', sizeof(princ_s));
 575         ZERO_STRUCT(kt_entry);
 576         ZERO_STRUCT(cursor);
 577
 578         initialize_krb5_error_table();
 579         ret = krb5_init_context(&context);
 580         if (ret) {
 581                 DEBUG(1, (__location__ ": could not krb5_init_context: %s\n",
 582                           error_message(ret)));
 583                 goto done;
 584         }
 585
 586         machine_name = talloc_strdup(frame, lp_netbios_name());
 587         if (!machine_name) {
 588                 ret = -1;
 589                 goto done;
 590         }
 591
 592         /* now add the userPrincipalName and sAMAccountName entries */
 593         sam_account_name = ads_get_samaccountname(ads, frame, machine_name);
 594         if (!sam_account_name) {
 595                 DEBUG(0, (__location__ ": unable to determine machine "
 596                           "account's name in AD!\n"));
 597                 ret = -1;
 598                 goto done;
 599         }
 600
 601         /* upper case the sAMAccountName to make it easier for apps to
 602            know what case to use in the keytab file */
 603         if (!strupper_m(sam_account_name)) {
 604                 ret = -1;
 605                 goto done;
 606         }
 607
 608         ret = ads_keytab_add_entry(ads, sam_account_name);
 609         if (ret != 0) {
 610                 DEBUG(1, (__location__ ": ads_keytab_add_entry() failed "
 611                           "while adding sAMAccountName (%s)\n",
 612                           sam_account_name));
 613                 goto done;
 614         }
 615
 616         /* remember that not every machine account will have a upn */
 617         upn = ads_get_upn(ads, frame, machine_name);
 618         if (upn) {
 619                 ret = ads_keytab_add_entry(ads, upn);
 620                 if (ret != 0) {
 621                         DEBUG(1, (__location__ ": ads_keytab_add_entry() "
 622                                   "failed while adding UPN (%s)\n", upn));
 623                         goto done;
 624                 }
 625         }
 626
 627         /* Now loop through the keytab and update any other existing entries */
 628         kvno = (krb5_kvno)ads_get_machine_kvno(ads, machine_name);
 629         if (kvno == (krb5_kvno)-1) {
 630                 DEBUG(1, (__location__ ": ads_get_machine_kvno() failed to "
 631                           "determine the system's kvno.\n"));
 632                 goto done;
 633         }
 634
 635         DEBUG(3, (__location__ ": Searching for keytab entries to preserve "
 636                   "and update.\n"));
 637
 638         ret = smb_krb5_open_keytab(context, NULL, True, &keytab);
 639         if (ret) {
 640                 DEBUG(1, (__location__ ": smb_krb5_open_keytab failed (%s)\n",
 641                           error_message(ret)));
 642                 goto done;
 643         }
 644
 645         ret = krb5_kt_start_seq_get(context, keytab, &cursor);
 646         if (ret != KRB5_KT_END && ret != ENOENT ) {
 647                 while ((ret = krb5_kt_next_entry(context, keytab,
 648                                                  &kt_entry, &cursor)) == 0) {
 649                         smb_krb5_kt_free_entry(context, &kt_entry);
 650                         ZERO_STRUCT(kt_entry);
 651                         found++;
 652                 }
 653         }
 654         krb5_kt_end_seq_get(context, keytab, &cursor);
 655         ZERO_STRUCT(cursor);
 656
 657         /*
 658          * Hmmm. There is no "rewind" function for the keytab. This means we
 659          * have a race condition where someone else could add entries after
 660          * we've counted them. Re-open asap to minimise the race. JRA.
 661          */
 662         DEBUG(3, (__location__ ": Found %zd entries in the keytab.\n", found));
 663         if (!found) {
 664                 goto done;
 665         }
 666
 667         oldEntries = talloc_zero_array(frame, char *, found + 1);
 668         if (!oldEntries) {
 669                 DEBUG(1, (__location__ ": Failed to allocate space to store "
 670                           "the old keytab entries (talloc failed?).\n"));
 671                 ret = -1;
 672                 goto done;
 673         }
 674
 675         ret = krb5_kt_start_seq_get(context, keytab, &cursor);
 676         if (ret == KRB5_KT_END || ret == ENOENT) {
 677                 krb5_kt_end_seq_get(context, keytab, &cursor);
 678                 ZERO_STRUCT(cursor);
 679                 goto done;
 680         }
 681
 682         while (krb5_kt_next_entry(context, keytab, &kt_entry, &cursor) == 0) {
 683                 if (kt_entry.vno != kvno) {
 684                         char *ktprinc = NULL;
 685                         char *p;
 686
 687                         /* This returns a malloc'ed string in ktprinc. */
 688                         ret = smb_krb5_unparse_name(oldEntries, context,
 689                                                     kt_entry.principal,
 690                                                     &ktprinc);
 691                         if (ret) {
 692                                 DEBUG(1, (__location__
 693                                          ": smb_krb5_unparse_name failed "
 694                                          "(%s)\n", error_message(ret)));
 695                                 goto done;
 696                         }
 697                         /*
 698                          * From looking at the krb5 source they don't seem to
 699                          * take locale or mb strings into account.
 700                          * Maybe this is because they assume utf8 ?
 701                          * In this case we may need to convert from utf8 to
 702                          * mb charset here ? JRA.
 703                          */
 704                         p = strchr_m(ktprinc, '@');
 705                         if (p) {
 706                                 *p = '\0';
 707                         }
 708
 709                         p = strchr_m(ktprinc, '/');
 710                         if (p) {
 711                                 *p = '\0';
 712                         }
 713                         for (i = 0; i < found; i++) {
 714                                 if (!oldEntries[i]) {
 715                                         oldEntries[i] = ktprinc;
 716                                         break;
 717                                 }
 718                                 if (!strcmp(oldEntries[i], ktprinc)) {
 719                                         TALLOC_FREE(ktprinc);
 720                                         break;
 721                                 }
 722                         }
 723                         if (i == found) {
 724                                 TALLOC_FREE(ktprinc);
 725                         }
 726                 }
 727                 smb_krb5_kt_free_entry(context, &kt_entry);
 728                 ZERO_STRUCT(kt_entry);
 729         }
 730         ret = 0;
 731         for (i = 0; oldEntries[i]; i++) {
 732                 ret |= ads_keytab_add_entry(ads, oldEntries[i]);
 733                 TALLOC_FREE(oldEntries[i]);
 734         }
 735         krb5_kt_end_seq_get(context, keytab, &cursor);
 736         ZERO_STRUCT(cursor);
 737
 738 done:
 739         TALLOC_FREE(oldEntries);
 740         TALLOC_FREE(frame);
 741
 742         {
 743                 krb5_keytab_entry zero_kt_entry;
 744                 ZERO_STRUCT(zero_kt_entry);
 745                 if (memcmp(&zero_kt_entry, &kt_entry,
 746                                 sizeof(krb5_keytab_entry))) {
 747                         smb_krb5_kt_free_entry(context, &kt_entry);
 748                 }
 749         }
 750         {
 751                 krb5_kt_cursor zero_csr;
 752                 ZERO_STRUCT(zero_csr);
 753                 if ((memcmp(&cursor, &zero_csr,
 754                                 sizeof(krb5_kt_cursor)) != 0) && keytab) {
 755                         krb5_kt_end_seq_get(context, keytab, &cursor);
 756                 }
 757         }
 758         if (keytab) {
 759                 krb5_kt_close(context, keytab);
 760         }
 761         if (context) {
 762                 krb5_free_context(context);
 763         }
 764         return ret;
 765 }
 766
 767 #endif /* HAVE_ADS */
 768
 769 /**********************************************************************
 770  List system keytab.
 771 ***********************************************************************/
 772
 773 int ads_keytab_list(const char *keytab_name)
 774 {
 775         krb5_error_code ret = 0;
 776         krb5_context context = NULL;
 777         krb5_keytab keytab = NULL;
 778         krb5_kt_cursor cursor;
 779         krb5_keytab_entry kt_entry;
 780
 781         ZERO_STRUCT(kt_entry);
 782         ZERO_STRUCT(cursor);
 783
 784         initialize_krb5_error_table();
 785         ret = krb5_init_context(&context);
 786         if (ret) {
 787                 DEBUG(1, (__location__ ": could not krb5_init_context: %s\n",
 788                           error_message(ret)));
 789                 return ret;
 790         }
 791
 792         ret = smb_krb5_open_keytab(context, keytab_name, False, &keytab);
 793         if (ret) {
 794                 DEBUG(1, (__location__ ": smb_krb5_open_keytab failed (%s)\n",
 795                           error_message(ret)));
 796                 goto out;
 797         }
 798
 799         ret = krb5_kt_start_seq_get(context, keytab, &cursor);
 800         if (ret) {
 801                 ZERO_STRUCT(cursor);
 802                 goto out;
 803         }
 804
 805         printf("Vno  Type                                        Principal\n");
 806
 807         while (krb5_kt_next_entry(context, keytab, &kt_entry, &cursor) == 0) {
 808
 809                 char *princ_s = NULL;
 810                 char *etype_s = NULL;
 811                 krb5_enctype enctype = 0;
 812
 813                 ret = smb_krb5_unparse_name(talloc_tos(), context,
 814                                             kt_entry.principal, &princ_s);
 815                 if (ret) {
 816                         goto out;
 817                 }
 818
 819                 enctype = smb_get_enctype_from_kt_entry(&kt_entry);
 820
 821                 ret = smb_krb5_enctype_to_string(context, enctype, &etype_s);
 822                 if (ret &&
 823                     (asprintf(&etype_s, "UNKNOWN: %d\n", enctype) == -1)) {
 824                         TALLOC_FREE(princ_s);
 825                         goto out;
 826                 }
 827
 828                 printf("%3d  %-43s %s\n", kt_entry.vno, etype_s, princ_s);
 829
 830                 TALLOC_FREE(princ_s);
 831                 SAFE_FREE(etype_s);
 832
 833                 ret = smb_krb5_kt_free_entry(context, &kt_entry);
 834                 if (ret) {
 835                         goto out;
 836                 }
 837         }
 838
 839         ret = krb5_kt_end_seq_get(context, keytab, &cursor);
 840         if (ret) {
 841                 goto out;
 842         }
 843
 844         /* Ensure we don't double free. */
 845         ZERO_STRUCT(kt_entry);
 846         ZERO_STRUCT(cursor);
 847 out:
 848
 849         {
 850                 krb5_keytab_entry zero_kt_entry;
 851                 ZERO_STRUCT(zero_kt_entry);
 852                 if (memcmp(&zero_kt_entry, &kt_entry,
 853                                 sizeof(krb5_keytab_entry))) {
 854                         smb_krb5_kt_free_entry(context, &kt_entry);
 855                 }
 856         }
 857         {
 858                 krb5_kt_cursor zero_csr;
 859                 ZERO_STRUCT(zero_csr);
 860                 if ((memcmp(&cursor, &zero_csr,
 861                                 sizeof(krb5_kt_cursor)) != 0) && keytab) {
 862                         krb5_kt_end_seq_get(context, keytab, &cursor);
 863                 }
 864         }
 865
 866         if (keytab) {
 867                 krb5_kt_close(context, keytab);
 868         }
 869         if (context) {
 870                 krb5_free_context(context);
 871         }
 872         return ret;
 873 }
 874
 875 #endif /* HAVE_KRB5 */