source3/libads/kerberos.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    kerberos utility library
   4    Copyright (C) Andrew Tridgell 2001
   5    Copyright (C) Remus Koos 2001
   6    Copyright (C) Nalin Dahyabhai <nalin@redhat.com> 2004.
   7    Copyright (C) Jeremy Allison 2004.
   8    Copyright (C) Gerald Carter 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 "system/filesys.h"
  26 #include "smb_krb5.h"
  27 #include "../librpc/gen_ndr/ndr_misc.h"
  28 #include "libads/kerberos_proto.h"
  29 #include "libads/cldap.h"
  30 #include "secrets.h"
  31 #include "../lib/tsocket/tsocket.h"
  32
  33 #ifdef HAVE_KRB5
  34
  35 #define DEFAULT_KRB5_PORT 88
  36
  37 #define LIBADS_CCACHE_NAME "MEMORY:libads"
  38
  39 /*
  40   we use a prompter to avoid a crash bug in the kerberos libs when
  41   dealing with empty passwords
  42   this prompter is just a string copy ...
  43 */
  44 static krb5_error_code
  45 kerb_prompter(krb5_context ctx, void *data,
  46                const char *name,
  47                const char *banner,
  48                int num_prompts,
  49                krb5_prompt prompts[])
  50 {
  51         if (num_prompts == 0) return 0;
  52
  53         memset(prompts[0].reply->data, '\0', prompts[0].reply->length);
  54         if (prompts[0].reply->length > 0) {
  55                 if (data) {
  56                         strncpy((char *)prompts[0].reply->data, (const char *)data,
  57                                 prompts[0].reply->length-1);
  58                         prompts[0].reply->length = strlen((const char *)prompts[0].reply->data);
  59                 } else {
  60                         prompts[0].reply->length = 0;
  61                 }
  62         }
  63         return 0;
  64 }
  65
  66  static bool smb_krb5_get_ntstatus_from_krb5_error(krb5_error *error,
  67                                                    NTSTATUS *nt_status)
  68 {
  69         DATA_BLOB edata;
  70         DATA_BLOB unwrapped_edata;
  71         TALLOC_CTX *mem_ctx;
  72         struct KRB5_EDATA_NTSTATUS parsed_edata;
  73         enum ndr_err_code ndr_err;
  74
  75 #ifdef HAVE_E_DATA_POINTER_IN_KRB5_ERROR
  76         edata = data_blob(error->e_data->data, error->e_data->length);
  77 #else
  78         edata = data_blob(error->e_data.data, error->e_data.length);
  79 #endif /* HAVE_E_DATA_POINTER_IN_KRB5_ERROR */
  80
  81 #ifdef DEVELOPER
  82         dump_data(10, edata.data, edata.length);
  83 #endif /* DEVELOPER */
  84
  85         mem_ctx = talloc_init("smb_krb5_get_ntstatus_from_krb5_error");
  86         if (mem_ctx == NULL) {
  87                 data_blob_free(&edata);
  88                 return False;
  89         }
  90
  91         if (!unwrap_edata_ntstatus(mem_ctx, &edata, &unwrapped_edata)) {
  92                 data_blob_free(&edata);
  93                 TALLOC_FREE(mem_ctx);
  94                 return False;
  95         }
  96
  97         data_blob_free(&edata);
  98
  99         ndr_err = ndr_pull_struct_blob_all(&unwrapped_edata, mem_ctx,
 100                 &parsed_edata, (ndr_pull_flags_fn_t)ndr_pull_KRB5_EDATA_NTSTATUS);
 101         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 102                 data_blob_free(&unwrapped_edata);
 103                 TALLOC_FREE(mem_ctx);
 104                 return False;
 105         }
 106
 107         data_blob_free(&unwrapped_edata);
 108
 109         if (nt_status) {
 110                 *nt_status = parsed_edata.ntstatus;
 111         }
 112
 113         TALLOC_FREE(mem_ctx);
 114
 115         return True;
 116 }
 117
 118  static bool smb_krb5_get_ntstatus_from_krb5_error_init_creds_opt(krb5_context ctx,
 119                                                                   krb5_get_init_creds_opt *opt,
 120                                                                   NTSTATUS *nt_status)
 121 {
 122         bool ret = False;
 123         krb5_error *error = NULL;
 124
 125 #ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_GET_ERROR
 126         ret = krb5_get_init_creds_opt_get_error(ctx, opt, &error);
 127         if (ret) {
 128                 DEBUG(1,("krb5_get_init_creds_opt_get_error gave: %s\n",
 129                         error_message(ret)));
 130                 return False;
 131         }
 132 #endif /* HAVE_KRB5_GET_INIT_CREDS_OPT_GET_ERROR */
 133
 134         if (!error) {
 135                 DEBUG(1,("no krb5_error\n"));
 136                 return False;
 137         }
 138
 139 #ifdef HAVE_E_DATA_POINTER_IN_KRB5_ERROR
 140         if (!error->e_data) {
 141 #else
 142         if (error->e_data.data == NULL) {
 143 #endif /* HAVE_E_DATA_POINTER_IN_KRB5_ERROR */
 144                 DEBUG(1,("no edata in krb5_error\n"));
 145                 krb5_free_error(ctx, error);
 146                 return False;
 147         }
 148
 149         ret = smb_krb5_get_ntstatus_from_krb5_error(error, nt_status);
 150
 151         krb5_free_error(ctx, error);
 152
 153         return ret;
 154 }
 155
 156 /*
 157   simulate a kinit, putting the tgt in the given cache location. If cache_name == NULL
 158   place in default cache location.
 159   remus@snapserver.com
 160 */
 161 int kerberos_kinit_password_ext(const char *principal,
 162                                 const char *password,
 163                                 int time_offset,
 164                                 time_t *expire_time,
 165                                 time_t *renew_till_time,
 166                                 const char *cache_name,
 167                                 bool request_pac,
 168                                 bool add_netbios_addr,
 169                                 time_t renewable_time,
 170                                 NTSTATUS *ntstatus)
 171 {
 172         krb5_context ctx = NULL;
 173         krb5_error_code code = 0;
 174         krb5_ccache cc = NULL;
 175         krb5_principal me = NULL;
 176         krb5_creds my_creds;
 177         krb5_get_init_creds_opt *opt = NULL;
 178         smb_krb5_addresses *addr = NULL;
 179
 180         ZERO_STRUCT(my_creds);
 181
 182         initialize_krb5_error_table();
 183         if ((code = krb5_init_context(&ctx)))
 184                 goto out;
 185
 186         if (time_offset != 0) {
 187                 krb5_set_real_time(ctx, time(NULL) + time_offset, 0);
 188         }
 189
 190         DEBUG(10,("kerberos_kinit_password: as %s using [%s] as ccache and config [%s]\n",
 191                         principal,
 192                         cache_name ? cache_name: krb5_cc_default_name(ctx),
 193                         getenv("KRB5_CONFIG")));
 194
 195         if ((code = krb5_cc_resolve(ctx, cache_name ? cache_name : krb5_cc_default_name(ctx), &cc))) {
 196                 goto out;
 197         }
 198
 199         if ((code = smb_krb5_parse_name(ctx, principal, &me))) {
 200                 goto out;
 201         }
 202
 203         if ((code = smb_krb5_get_init_creds_opt_alloc(ctx, &opt))) {
 204                 goto out;
 205         }
 206
 207         krb5_get_init_creds_opt_set_renew_life(opt, renewable_time);
 208         krb5_get_init_creds_opt_set_forwardable(opt, True);
 209 #if 0
 210         /* insane testing */
 211         krb5_get_init_creds_opt_set_tkt_life(opt, 60);
 212 #endif
 213
 214 #ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_SET_PAC_REQUEST
 215         if (request_pac) {
 216                 if ((code = krb5_get_init_creds_opt_set_pac_request(ctx, opt, (krb5_boolean)request_pac))) {
 217                         goto out;
 218                 }
 219         }
 220 #endif
 221         if (add_netbios_addr) {
 222                 if ((code = smb_krb5_gen_netbios_krb5_address(&addr,
 223                                                         lp_netbios_name()))) {
 224                         goto out;
 225                 }
 226                 krb5_get_init_creds_opt_set_address_list(opt, addr->addrs);
 227         }
 228
 229         if ((code = krb5_get_init_creds_password(ctx, &my_creds, me, discard_const_p(char,password),
 230                                                  kerb_prompter, discard_const_p(char, password),
 231                                                  0, NULL, opt))) {
 232                 goto out;
 233         }
 234
 235         if ((code = krb5_cc_initialize(ctx, cc, me))) {
 236                 goto out;
 237         }
 238
 239         if ((code = krb5_cc_store_cred(ctx, cc, &my_creds))) {
 240                 goto out;
 241         }
 242
 243         if (expire_time) {
 244                 *expire_time = (time_t) my_creds.times.endtime;
 245         }
 246
 247         if (renew_till_time) {
 248                 *renew_till_time = (time_t) my_creds.times.renew_till;
 249         }
 250  out:
 251         if (ntstatus) {
 252
 253                 NTSTATUS status;
 254
 255                 /* fast path */
 256                 if (code == 0) {
 257                         *ntstatus = NT_STATUS_OK;
 258                         goto cleanup;
 259                 }
 260
 261                 /* try to get ntstatus code out of krb5_error when we have it
 262                  * inside the krb5_get_init_creds_opt - gd */
 263
 264                 if (opt && smb_krb5_get_ntstatus_from_krb5_error_init_creds_opt(ctx, opt, &status)) {
 265                         *ntstatus = status;
 266                         goto cleanup;
 267                 }
 268
 269                 /* fall back to self-made-mapping */
 270                 *ntstatus = krb5_to_nt_status(code);
 271         }
 272
 273  cleanup:
 274         krb5_free_cred_contents(ctx, &my_creds);
 275         if (me) {
 276                 krb5_free_principal(ctx, me);
 277         }
 278         if (addr) {
 279                 smb_krb5_free_addresses(ctx, addr);
 280         }
 281         if (opt) {
 282                 smb_krb5_get_init_creds_opt_free(ctx, opt);
 283         }
 284         if (cc) {
 285                 krb5_cc_close(ctx, cc);
 286         }
 287         if (ctx) {
 288                 krb5_free_context(ctx);
 289         }
 290         return code;
 291 }
 292
 293 int ads_kdestroy(const char *cc_name)
 294 {
 295         krb5_error_code code;
 296         krb5_context ctx = NULL;
 297         krb5_ccache cc = NULL;
 298
 299         initialize_krb5_error_table();
 300         if ((code = krb5_init_context (&ctx))) {
 301                 DEBUG(3, ("ads_kdestroy: kdb5_init_context failed: %s\n",
 302                         error_message(code)));
 303                 return code;
 304         }
 305
 306         if (!cc_name) {
 307                 if ((code = krb5_cc_default(ctx, &cc))) {
 308                         krb5_free_context(ctx);
 309                         return code;
 310                 }
 311         } else {
 312                 if ((code = krb5_cc_resolve(ctx, cc_name, &cc))) {
 313                         DEBUG(3, ("ads_kdestroy: krb5_cc_resolve failed: %s\n",
 314                                   error_message(code)));
 315                         krb5_free_context(ctx);
 316                         return code;
 317                 }
 318         }
 319
 320         if ((code = krb5_cc_destroy (ctx, cc))) {
 321                 DEBUG(3, ("ads_kdestroy: krb5_cc_destroy failed: %s\n",
 322                         error_message(code)));
 323         }
 324
 325         krb5_free_context (ctx);
 326         return code;
 327 }
 328
 329 /************************************************************************
 330  Routine to fetch the salting principal for a service.  Active
 331  Directory may use a non-obvious principal name to generate the salt
 332  when it determines the key to use for encrypting tickets for a service,
 333  and hopefully we detected that when we joined the domain.
 334  ************************************************************************/
 335
 336 static char *kerberos_secrets_fetch_salting_principal(const char *service, int enctype)
 337 {
 338         char *key = NULL;
 339         char *ret = NULL;
 340
 341         if (asprintf(&key, "%s/%s/enctype=%d",
 342                      SECRETS_SALTING_PRINCIPAL, service, enctype) == -1) {
 343                 return NULL;
 344         }
 345         ret = (char *)secrets_fetch(key, NULL);
 346         SAFE_FREE(key);
 347         return ret;
 348 }
 349
 350 /************************************************************************
 351  Return the standard DES salt key
 352 ************************************************************************/
 353
 354 char* kerberos_standard_des_salt( void )
 355 {
 356         fstring salt;
 357
 358         fstr_sprintf( salt, "host/%s.%s@", lp_netbios_name(), lp_realm() );
 359         (void)strlower_m( salt );
 360         fstrcat( salt, lp_realm() );
 361
 362         return SMB_STRDUP( salt );
 363 }
 364
 365 /************************************************************************
 366 ************************************************************************/
 367
 368 static char* des_salt_key( void )
 369 {
 370         char *key;
 371
 372         if (asprintf(&key, "%s/DES/%s", SECRETS_SALTING_PRINCIPAL,
 373                      lp_realm()) == -1) {
 374                 return NULL;
 375         }
 376
 377         return key;
 378 }
 379
 380 /************************************************************************
 381 ************************************************************************/
 382
 383 bool kerberos_secrets_store_des_salt( const char* salt )
 384 {
 385         char* key;
 386         bool ret;
 387
 388         if ( (key = des_salt_key()) == NULL ) {
 389                 DEBUG(0,("kerberos_secrets_store_des_salt: failed to generate key!\n"));
 390                 return False;
 391         }
 392
 393         if ( !salt ) {
 394                 DEBUG(8,("kerberos_secrets_store_des_salt: deleting salt\n"));
 395                 secrets_delete( key );
 396                 return True;
 397         }
 398
 399         DEBUG(3,("kerberos_secrets_store_des_salt: Storing salt \"%s\"\n", salt));
 400
 401         ret = secrets_store( key, salt, strlen(salt)+1 );
 402
 403         SAFE_FREE( key );
 404
 405         return ret;
 406 }
 407
 408 /************************************************************************
 409 ************************************************************************/
 410
 411 static
 412 char* kerberos_secrets_fetch_des_salt( void )
 413 {
 414         char *salt, *key;
 415
 416         if ( (key = des_salt_key()) == NULL ) {
 417                 DEBUG(0,("kerberos_secrets_fetch_des_salt: failed to generate key!\n"));
 418                 return NULL;
 419         }
 420
 421         salt = (char*)secrets_fetch( key, NULL );
 422
 423         SAFE_FREE( key );
 424
 425         return salt;
 426 }
 427
 428 /************************************************************************
 429  Routine to get the salting principal for this service.  This is
 430  maintained for backwards compatibilty with releases prior to 3.0.24.
 431  Since we store the salting principal string only at join, we may have
 432  to look for the older tdb keys.  Caller must free if return is not null.
 433  ************************************************************************/
 434
 435 static
 436 krb5_principal kerberos_fetch_salt_princ_for_host_princ(krb5_context context,
 437                                                         krb5_principal host_princ,
 438                                                         int enctype)
 439 {
 440         char *unparsed_name = NULL, *salt_princ_s = NULL;
 441         krb5_principal ret_princ = NULL;
 442
 443         /* lookup new key first */
 444
 445         if ( (salt_princ_s = kerberos_secrets_fetch_des_salt()) == NULL ) {
 446
 447                 /* look under the old key.  If this fails, just use the standard key */
 448
 449                 if (smb_krb5_unparse_name(talloc_tos(), context, host_princ, &unparsed_name) != 0) {
 450                         return (krb5_principal)NULL;
 451                 }
 452                 if ((salt_princ_s = kerberos_secrets_fetch_salting_principal(unparsed_name, enctype)) == NULL) {
 453                         /* fall back to host/machine.realm@REALM */
 454                         salt_princ_s = kerberos_standard_des_salt();
 455                 }
 456         }
 457
 458         if (smb_krb5_parse_name(context, salt_princ_s, &ret_princ) != 0) {
 459                 ret_princ = NULL;
 460         }
 461
 462         TALLOC_FREE(unparsed_name);
 463         SAFE_FREE(salt_princ_s);
 464
 465         return ret_princ;
 466 }
 467
 468 int create_kerberos_key_from_string(krb5_context context,
 469                                         krb5_principal host_princ,
 470                                         krb5_data *password,
 471                                         krb5_keyblock *key,
 472                                         krb5_enctype enctype,
 473                                         bool no_salt)
 474 {
 475         krb5_principal salt_princ = NULL;
 476         int ret;
 477         /*
 478          * Check if we've determined that the KDC is salting keys for this
 479          * principal/enctype in a non-obvious way.  If it is, try to match
 480          * its behavior.
 481          */
 482         if (no_salt) {
 483                 KRB5_KEY_DATA(key) = (KRB5_KEY_DATA_CAST *)SMB_MALLOC(password->length);
 484                 if (!KRB5_KEY_DATA(key)) {
 485                         return ENOMEM;
 486                 }
 487                 memcpy(KRB5_KEY_DATA(key), password->data, password->length);
 488                 KRB5_KEY_LENGTH(key) = password->length;
 489                 KRB5_KEY_TYPE(key) = enctype;
 490                 return 0;
 491         }
 492         salt_princ = kerberos_fetch_salt_princ_for_host_princ(context, host_princ, enctype);
 493         ret = create_kerberos_key_from_string_direct(context, salt_princ ? salt_princ : host_princ, password, key, enctype);
 494         if (salt_princ) {
 495                 krb5_free_principal(context, salt_princ);
 496         }
 497         return ret;
 498 }
 499
 500 /************************************************************************
 501  Routine to set the salting principal for this service.  Active
 502  Directory may use a non-obvious principal name to generate the salt
 503  when it determines the key to use for encrypting tickets for a service,
 504  and hopefully we detected that when we joined the domain.
 505  Setting principal to NULL deletes this entry.
 506  ************************************************************************/
 507
 508 bool kerberos_secrets_store_salting_principal(const char *service,
 509                                               int enctype,
 510                                               const char *principal)
 511 {
 512         char *key = NULL;
 513         bool ret = False;
 514         krb5_context context = NULL;
 515         krb5_principal princ = NULL;
 516         char *princ_s = NULL;
 517         char *unparsed_name = NULL;
 518         krb5_error_code code;
 519
 520         if (((code = krb5_init_context(&context)) != 0) || (context == NULL)) {
 521                 DEBUG(5, ("kerberos_secrets_store_salting_pricipal: kdb5_init_context failed: %s\n",
 522                           error_message(code)));
 523                 return False;
 524         }
 525         if (strchr_m(service, '@')) {
 526                 if (asprintf(&princ_s, "%s", service) == -1) {
 527                         goto out;
 528                 }
 529         } else {
 530                 if (asprintf(&princ_s, "%s@%s", service, lp_realm()) == -1) {
 531                         goto out;
 532                 }
 533         }
 534
 535         if (smb_krb5_parse_name(context, princ_s, &princ) != 0) {
 536                 goto out;
 537         }
 538         if (smb_krb5_unparse_name(talloc_tos(), context, princ, &unparsed_name) != 0) {
 539                 goto out;
 540         }
 541
 542         if (asprintf(&key, "%s/%s/enctype=%d",
 543                      SECRETS_SALTING_PRINCIPAL, unparsed_name, enctype)
 544             == -1) {
 545                 goto out;
 546         }
 547
 548         if ((principal != NULL) && (strlen(principal) > 0)) {
 549                 ret = secrets_store(key, principal, strlen(principal) + 1);
 550         } else {
 551                 ret = secrets_delete(key);
 552         }
 553
 554  out:
 555
 556         SAFE_FREE(key);
 557         SAFE_FREE(princ_s);
 558         TALLOC_FREE(unparsed_name);
 559
 560         if (princ) {
 561                 krb5_free_principal(context, princ);
 562         }
 563
 564         if (context) {
 565                 krb5_free_context(context);
 566         }
 567
 568         return ret;
 569 }
 570
 571
 572 /************************************************************************
 573 ************************************************************************/
 574
 575 int kerberos_kinit_password(const char *principal,
 576                             const char *password,
 577                             int time_offset,
 578                             const char *cache_name)
 579 {
 580         return kerberos_kinit_password_ext(principal,
 581                                            password,
 582                                            time_offset,
 583                                            0,
 584                                            0,
 585                                            cache_name,
 586                                            False,
 587                                            False,
 588                                            0,
 589                                            NULL);
 590 }
 591
 592 /************************************************************************
 593 ************************************************************************/
 594
 595 static char *print_kdc_line(char *mem_ctx,
 596                         const char *prev_line,
 597                         const struct sockaddr_storage *pss,
 598                         const char *kdc_name)
 599 {
 600         char addr[INET6_ADDRSTRLEN];
 601         uint16_t port = get_sockaddr_port(pss);
 602
 603         if (pss->ss_family == AF_INET) {
 604                 return talloc_asprintf(mem_ctx, "%s\tkdc = %s\n",
 605                                        prev_line,
 606                                        print_canonical_sockaddr(mem_ctx, pss));
 607         }
 608
 609         /*
 610          * IPv6 starts here
 611          */
 612
 613         DEBUG(10, ("print_kdc_line: IPv6 case for kdc_name: %s, port: %d\n",
 614                    kdc_name, port));
 615
 616         if (port != 0 && port != DEFAULT_KRB5_PORT) {
 617                 /* Currently for IPv6 we can't specify a non-default
 618                    krb5 port with an address, as this requires a ':'.
 619                    Resolve to a name. */
 620                 char hostname[MAX_DNS_NAME_LENGTH];
 621                 int ret = sys_getnameinfo((const struct sockaddr *)pss,
 622                                           sizeof(*pss),
 623                                           hostname, sizeof(hostname),
 624                                           NULL, 0,
 625                                           NI_NAMEREQD);
 626                 if (ret) {
 627                         DEBUG(0,("print_kdc_line: can't resolve name "
 628                                  "for kdc with non-default port %s. "
 629                                  "Error %s\n.",
 630                                  print_canonical_sockaddr(mem_ctx, pss),
 631                                  gai_strerror(ret)));
 632                         return NULL;
 633                 }
 634                 /* Success, use host:port */
 635                 return talloc_asprintf(mem_ctx,
 636                                        "%s\tkdc = %s:%u\n",
 637                                        prev_line,
 638                                        hostname,
 639                                        (unsigned int)port);
 640         }
 641
 642         /* no krb5 lib currently supports "kdc = ipv6 address"
 643          * at all, so just fill in just the kdc_name if we have
 644          * it and let the krb5 lib figure out the appropriate
 645          * ipv6 address - gd */
 646
 647         if (kdc_name) {
 648                 return talloc_asprintf(mem_ctx, "%s\tkdc = %s\n",
 649                                        prev_line, kdc_name);
 650         }
 651
 652         return talloc_asprintf(mem_ctx, "%s\tkdc = %s\n",
 653                                prev_line,
 654                                print_sockaddr(addr,
 655                                               sizeof(addr),
 656                                               pss));
 657 }
 658
 659 /************************************************************************
 660  Create a string list of available kdc's, possibly searching by sitename.
 661  Does DNS queries.
 662
 663  If "sitename" is given, the DC's in that site are listed first.
 664
 665 ************************************************************************/
 666
 667 static void add_sockaddr_unique(struct sockaddr_storage *addrs, int *num_addrs,
 668                                 const struct sockaddr_storage *addr)
 669 {
 670         int i;
 671
 672         for (i=0; i<*num_addrs; i++) {
 673                 if (sockaddr_equal((const struct sockaddr *)&addrs[i],
 674                                    (const struct sockaddr *)addr)) {
 675                         return;
 676                 }
 677         }
 678         addrs[i] = *addr;
 679         *num_addrs += 1;
 680 }
 681
 682 static char *get_kdc_ip_string(char *mem_ctx,
 683                 const char *realm,
 684                 const char *sitename,
 685                 const struct sockaddr_storage *pss,
 686                 const char *kdc_name)
 687 {
 688         TALLOC_CTX *frame = talloc_stackframe();
 689         int i;
 690         struct ip_service *ip_srv_site = NULL;
 691         struct ip_service *ip_srv_nonsite = NULL;
 692         int count_site = 0;
 693         int count_nonsite;
 694         int num_dcs;
 695         struct sockaddr_storage *dc_addrs;
 696         struct tsocket_address **dc_addrs2 = NULL;
 697         const struct tsocket_address * const *dc_addrs3 = NULL;
 698         char *result = NULL;
 699         struct netlogon_samlogon_response **responses = NULL;
 700         NTSTATUS status;
 701         char *kdc_str = print_kdc_line(mem_ctx, "", pss, kdc_name);
 702
 703         if (kdc_str == NULL) {
 704                 TALLOC_FREE(frame);
 705                 return NULL;
 706         }
 707
 708         /*
 709          * First get the KDC's only in this site, the rest will be
 710          * appended later
 711          */
 712
 713         if (sitename) {
 714                 get_kdc_list(realm, sitename, &ip_srv_site, &count_site);
 715         }
 716
 717         /* Get all KDC's. */
 718
 719         get_kdc_list(realm, NULL, &ip_srv_nonsite, &count_nonsite);
 720
 721         dc_addrs = talloc_array(talloc_tos(), struct sockaddr_storage,
 722                                 1 + count_site + count_nonsite);
 723         if (dc_addrs == NULL) {
 724                 goto fail;
 725         }
 726
 727         dc_addrs[0] = *pss;
 728         num_dcs = 1;
 729
 730         for (i=0; i<count_site; i++) {
 731                 add_sockaddr_unique(dc_addrs, &num_dcs, &ip_srv_site[i].ss);
 732         }
 733
 734         for (i=0; i<count_nonsite; i++) {
 735                 add_sockaddr_unique(dc_addrs, &num_dcs, &ip_srv_nonsite[i].ss);
 736         }
 737
 738         dc_addrs2 = talloc_zero_array(talloc_tos(),
 739                                       struct tsocket_address *,
 740                                       num_dcs);
 741         if (dc_addrs2 == NULL) {
 742                 goto fail;
 743         }
 744
 745         for (i=0; i<num_dcs; i++) {
 746                 char addr[INET6_ADDRSTRLEN];
 747                 int ret;
 748
 749                 print_sockaddr(addr, sizeof(addr), &dc_addrs[i]);
 750
 751                 ret = tsocket_address_inet_from_strings(dc_addrs2, "ip",
 752                                                         addr, LDAP_PORT,
 753                                                         &dc_addrs2[i]);
 754                 if (ret != 0) {
 755                         status = map_nt_error_from_unix(errno);
 756                         DEBUG(2,("Failed to create tsocket_address for %s - %s\n",
 757                                  addr, nt_errstr(status)));
 758                         goto fail;
 759                 }
 760         }
 761
 762         dc_addrs3 = (const struct tsocket_address * const *)dc_addrs2;
 763
 764         status = cldap_multi_netlogon(talloc_tos(),
 765                         dc_addrs3, num_dcs,
 766                         realm, lp_netbios_name(),
 767                         NETLOGON_NT_VERSION_5 | NETLOGON_NT_VERSION_5EX,
 768                         MIN(num_dcs, 3), timeval_current_ofs(3, 0), &responses);
 769         TALLOC_FREE(dc_addrs2);
 770         dc_addrs3 = NULL;
 771
 772         if (!NT_STATUS_IS_OK(status)) {
 773                 DEBUG(10,("get_kdc_ip_string: cldap_multi_netlogon failed: "
 774                           "%s\n", nt_errstr(status)));
 775                 goto fail;
 776         }
 777
 778         kdc_str = talloc_strdup(mem_ctx, "");
 779         if (kdc_str == NULL) {
 780                 goto fail;
 781         }
 782
 783         for (i=0; i<num_dcs; i++) {
 784                 char *new_kdc_str;
 785
 786                 if (responses[i] == NULL) {
 787                         continue;
 788                 }
 789
 790                 /* Append to the string - inefficient but not done often. */
 791                 new_kdc_str = print_kdc_line(mem_ctx, kdc_str,
 792                                              &dc_addrs[i],
 793                                              kdc_name);
 794                 if (new_kdc_str == NULL) {
 795                         goto fail;
 796                 }
 797                 TALLOC_FREE(kdc_str);
 798                 kdc_str = new_kdc_str;
 799         }
 800
 801         DEBUG(10,("get_kdc_ip_string: Returning %s\n",
 802                 kdc_str ));
 803
 804         result = kdc_str;
 805 fail:
 806         SAFE_FREE(ip_srv_site);
 807         SAFE_FREE(ip_srv_nonsite);
 808         TALLOC_FREE(frame);
 809         return result;
 810 }
 811
 812 /************************************************************************
 813  Create  a specific krb5.conf file in the private directory pointing
 814  at a specific kdc for a realm. Keyed off domain name. Sets
 815  KRB5_CONFIG environment variable to point to this file. Must be
 816  run as root or will fail (which is a good thing :-).
 817 ************************************************************************/
 818
 819 bool create_local_private_krb5_conf_for_domain(const char *realm,
 820                                                 const char *domain,
 821                                                 const char *sitename,
 822                                                 const struct sockaddr_storage *pss,
 823                                                 const char *kdc_name)
 824 {
 825         char *dname;
 826         char *tmpname = NULL;
 827         char *fname = NULL;
 828         char *file_contents = NULL;
 829         char *kdc_ip_string = NULL;
 830         size_t flen = 0;
 831         ssize_t ret;
 832         int fd;
 833         char *realm_upper = NULL;
 834         bool result = false;
 835         char *aes_enctypes = NULL;
 836         mode_t mask;
 837
 838         if (!lp_create_krb5_conf()) {
 839                 return false;
 840         }
 841
 842         if (realm == NULL) {
 843                 DEBUG(0, ("No realm has been specified! Do you really want to "
 844                           "join an Active Directory server?\n"));
 845                 return false;
 846         }
 847
 848         if (domain == NULL || pss == NULL || kdc_name == NULL) {
 849                 return false;
 850         }
 851
 852         dname = lock_path("smb_krb5");
 853         if (!dname) {
 854                 return false;
 855         }
 856         if ((mkdir(dname, 0755)==-1) && (errno != EEXIST)) {
 857                 DEBUG(0,("create_local_private_krb5_conf_for_domain: "
 858                         "failed to create directory %s. Error was %s\n",
 859                         dname, strerror(errno) ));
 860                 goto done;
 861         }
 862
 863         tmpname = lock_path("smb_tmp_krb5.XXXXXX");
 864         if (!tmpname) {
 865                 goto done;
 866         }
 867
 868         fname = talloc_asprintf(dname, "%s/krb5.conf.%s", dname, domain);
 869         if (!fname) {
 870                 goto done;
 871         }
 872
 873         DEBUG(10,("create_local_private_krb5_conf_for_domain: fname = %s, realm = %s, domain = %s\n",
 874                 fname, realm, domain ));
 875
 876         realm_upper = talloc_strdup(fname, realm);
 877         if (!strupper_m(realm_upper)) {
 878                 goto done;
 879         }
 880
 881         kdc_ip_string = get_kdc_ip_string(dname, realm, sitename, pss, kdc_name);
 882         if (!kdc_ip_string) {
 883                 goto done;
 884         }
 885
 886         aes_enctypes = talloc_strdup(fname, "");
 887         if (aes_enctypes == NULL) {
 888                 goto done;
 889         }
 890
 891 #ifdef HAVE_ENCTYPE_AES256_CTS_HMAC_SHA1_96
 892         aes_enctypes = talloc_asprintf_append(aes_enctypes, "%s", "aes256-cts-hmac-sha1-96 ");
 893         if (aes_enctypes == NULL) {
 894                 goto done;
 895         }
 896 #endif
 897 #ifdef HAVE_ENCTYPE_AES128_CTS_HMAC_SHA1_96
 898         aes_enctypes = talloc_asprintf_append(aes_enctypes, "%s", "aes128-cts-hmac-sha1-96");
 899         if (aes_enctypes == NULL) {
 900                 goto done;
 901         }
 902 #endif
 903
 904         file_contents = talloc_asprintf(fname,
 905                                         "[libdefaults]\n\tdefault_realm = %s\n"
 906                                         "\tdefault_tgs_enctypes = %s RC4-HMAC DES-CBC-CRC DES-CBC-MD5\n"
 907                                         "\tdefault_tkt_enctypes = %s RC4-HMAC DES-CBC-CRC DES-CBC-MD5\n"
 908                                         "\tpreferred_enctypes = %s RC4-HMAC DES-CBC-CRC DES-CBC-MD5\n\n"
 909                                         "[realms]\n\t%s = {\n"
 910                                         "\t%s\t}\n",
 911                                         realm_upper, aes_enctypes, aes_enctypes, aes_enctypes,
 912                                         realm_upper, kdc_ip_string);
 913
 914         if (!file_contents) {
 915                 goto done;
 916         }
 917
 918         flen = strlen(file_contents);
 919
 920         mask = umask(S_IRWXO | S_IRWXG);
 921         fd = mkstemp(tmpname);
 922         umask(mask);
 923         if (fd == -1) {
 924                 DEBUG(0,("create_local_private_krb5_conf_for_domain: smb_mkstemp failed,"
 925                         " for file %s. Errno %s\n",
 926                         tmpname, strerror(errno) ));
 927                 goto done;
 928         }
 929
 930         if (fchmod(fd, 0644)==-1) {
 931                 DEBUG(0,("create_local_private_krb5_conf_for_domain: fchmod failed for %s."
 932                         " Errno %s\n",
 933                         tmpname, strerror(errno) ));
 934                 unlink(tmpname);
 935                 close(fd);
 936                 goto done;
 937         }
 938
 939         ret = write(fd, file_contents, flen);
 940         if (flen != ret) {
 941                 DEBUG(0,("create_local_private_krb5_conf_for_domain: write failed,"
 942                         " returned %d (should be %u). Errno %s\n",
 943                         (int)ret, (unsigned int)flen, strerror(errno) ));
 944                 unlink(tmpname);
 945                 close(fd);
 946                 goto done;
 947         }
 948         if (close(fd)==-1) {
 949                 DEBUG(0,("create_local_private_krb5_conf_for_domain: close failed."
 950                         " Errno %s\n", strerror(errno) ));
 951                 unlink(tmpname);
 952                 goto done;
 953         }
 954
 955         if (rename(tmpname, fname) == -1) {
 956                 DEBUG(0,("create_local_private_krb5_conf_for_domain: rename "
 957                         "of %s to %s failed. Errno %s\n",
 958                         tmpname, fname, strerror(errno) ));
 959                 unlink(tmpname);
 960                 goto done;
 961         }
 962
 963         DEBUG(5,("create_local_private_krb5_conf_for_domain: wrote "
 964                 "file %s with realm %s KDC list = %s\n",
 965                 fname, realm_upper, kdc_ip_string));
 966
 967         /* Set the environment variable to this file. */
 968         setenv("KRB5_CONFIG", fname, 1);
 969
 970         result = true;
 971
 972 #if defined(OVERWRITE_SYSTEM_KRB5_CONF)
 973
 974 #define SYSTEM_KRB5_CONF_PATH "/etc/krb5.conf"
 975         /* Insanity, sheer insanity..... */
 976
 977         if (strequal(realm, lp_realm())) {
 978                 SMB_STRUCT_STAT sbuf;
 979
 980                 if (sys_lstat(SYSTEM_KRB5_CONF_PATH, &sbuf, false) == 0) {
 981                         if (S_ISLNK(sbuf.st_ex_mode) && sbuf.st_ex_size) {
 982                                 int lret;
 983                                 size_t alloc_size = sbuf.st_ex_size + 1;
 984                                 char *linkpath = talloc_array(talloc_tos(), char,
 985                                                 alloc_size);
 986                                 if (!linkpath) {
 987                                         goto done;
 988                                 }
 989                                 lret = readlink(SYSTEM_KRB5_CONF_PATH, linkpath,
 990                                                 alloc_size - 1);
 991                                 if (lret == -1) {
 992                                         TALLOC_FREE(linkpath);
 993                                         goto done;
 994                                 }
 995                                 linkpath[lret] = '\0';
 996
 997                                 if (strcmp(linkpath, fname) == 0) {
 998                                         /* Symlink already exists. */
 999                                         TALLOC_FREE(linkpath);
1000                                         goto done;
1001                                 }
1002                                 TALLOC_FREE(linkpath);
1003                         }
1004                 }
1005
1006                 /* Try and replace with a symlink. */
1007                 if (symlink(fname, SYSTEM_KRB5_CONF_PATH) == -1) {
1008                         const char *newpath = SYSTEM_KRB5_CONF_PATH ".saved";
1009                         if (errno != EEXIST) {
1010                                 DEBUG(0,("create_local_private_krb5_conf_for_domain: symlink "
1011                                         "of %s to %s failed. Errno %s\n",
1012                                         fname, SYSTEM_KRB5_CONF_PATH, strerror(errno) ));
1013                                 goto done; /* Not a fatal error. */
1014                         }
1015
1016                         /* Yes, this is a race conditon... too bad. */
1017                         if (rename(SYSTEM_KRB5_CONF_PATH, newpath) == -1) {
1018                                 DEBUG(0,("create_local_private_krb5_conf_for_domain: rename "
1019                                         "of %s to %s failed. Errno %s\n",
1020                                         SYSTEM_KRB5_CONF_PATH, newpath,
1021                                         strerror(errno) ));
1022                                 goto done; /* Not a fatal error. */
1023                         }
1024
1025                         if (symlink(fname, SYSTEM_KRB5_CONF_PATH) == -1) {
1026                                 DEBUG(0,("create_local_private_krb5_conf_for_domain: "
1027                                         "forced symlink of %s to /etc/krb5.conf failed. Errno %s\n",
1028                                         fname, strerror(errno) ));
1029                                 goto done; /* Not a fatal error. */
1030                         }
1031                 }
1032         }
1033 #endif
1034
1035 done:
1036         TALLOC_FREE(tmpname);
1037         TALLOC_FREE(dname);
1038
1039         return result;
1040 }
1041 #endif