lib/krb5_wrap/krb5_samba.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    simple kerberos5 routines for active directory
   4    Copyright (C) Andrew Tridgell 2001
   5    Copyright (C) Luke Howard 2002-2003
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
   7    Copyright (C) Guenther Deschner 2005-2009
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "system/filesys.h"
  25 #include "krb5_samba.h"
  26
  27 #ifdef HAVE_COM_ERR_H
  28 #include <com_err.h>
  29 #endif /* HAVE_COM_ERR_H */
  30
  31 #ifndef KRB5_AUTHDATA_WIN2K_PAC
  32 #define KRB5_AUTHDATA_WIN2K_PAC 128
  33 #endif
  34
  35 #ifndef KRB5_AUTHDATA_IF_RELEVANT
  36 #define KRB5_AUTHDATA_IF_RELEVANT 1
  37 #endif
  38
  39 #ifdef HAVE_KRB5
  40
  41 #define GSSAPI_CHECKSUM      0x8003             /* Checksum type value for Kerberos */
  42 #define GSSAPI_BNDLENGTH     16                 /* Bind Length (rfc-1964 pg.3) */
  43 #define GSSAPI_CHECKSUM_SIZE (4+GSSAPI_BNDLENGTH+4) /* Length of bind length,
  44                                                         bind field, flags field. */
  45 #define GSS_C_DELEG_FLAG 1
  46
  47 /* MIT krb5 1.7beta3 (in Ubuntu Karmic) is missing the prototype,
  48    but still has the symbol */
  49 #if !HAVE_DECL_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE
  50 krb5_error_code krb5_auth_con_set_req_cksumtype(
  51         krb5_context     context,
  52         krb5_auth_context      auth_context,
  53         krb5_cksumtype     cksumtype);
  54 #endif
  55
  56 #if !defined(SMB_MALLOC)
  57 #undef malloc
  58 #define SMB_MALLOC(s) malloc((s))
  59 #endif
  60
  61 #ifndef SMB_STRDUP
  62 #define SMB_STRDUP(s) strdup(s)
  63 #endif
  64
  65 /**********************************************************
  66  * MISSING FUNCTIONS
  67  **********************************************************/
  68
  69 #if !defined(HAVE_KRB5_SET_DEFAULT_TGS_KTYPES)
  70
  71 #if defined(HAVE_KRB5_SET_DEFAULT_TGS_ENCTYPES)
  72
  73 /* With MIT kerberos, we should use krb5_set_default_tgs_enctypes in preference
  74  * to krb5_set_default_tgs_ktypes. See
  75  *         http://lists.samba.org/archive/samba-technical/2006-July/048271.html
  76  *
  77  * If the MIT libraries are not exporting internal symbols, we will end up in
  78  * this branch, which is correct. Otherwise we will continue to use the
  79  * internal symbol
  80  */
  81  krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc)
  82 {
  83     return krb5_set_default_tgs_enctypes(ctx, enc);
  84 }
  85
  86 #elif defined(HAVE_KRB5_SET_DEFAULT_IN_TKT_ETYPES)
  87
  88 /* Heimdal */
  89  krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc)
  90 {
  91         return krb5_set_default_in_tkt_etypes(ctx, enc);
  92 }
  93
  94 #endif /* HAVE_KRB5_SET_DEFAULT_TGS_ENCTYPES */
  95
  96 #endif /* HAVE_KRB5_SET_DEFAULT_TGS_KTYPES */
  97
  98
  99 #if defined(HAVE_KRB5_AUTH_CON_SETKEY) && !defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY)
 100 krb5_error_code krb5_auth_con_setuseruserkey(krb5_context context,
 101                                              krb5_auth_context auth_context,
 102                                              krb5_keyblock *keyblock)
 103 {
 104         return krb5_auth_con_setkey(context, auth_context, keyblock);
 105 }
 106 #endif
 107
 108 #if !defined(HAVE_KRB5_FREE_UNPARSED_NAME)
 109 void krb5_free_unparsed_name(krb5_context context, char *val)
 110 {
 111         SAFE_FREE(val);
 112 }
 113 #endif
 114
 115 #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING) && !defined(HAVE_KRB5_PRINC_COMPONENT)
 116 const krb5_data *krb5_princ_component(krb5_context context,
 117                                       krb5_principal principal, int i);
 118
 119 const krb5_data *krb5_princ_component(krb5_context context,
 120                                       krb5_principal principal, int i)
 121 {
 122         static krb5_data kdata;
 123
 124         kdata.data = discard_const_p(char, krb5_principal_get_comp_string(context, principal, i));
 125         kdata.length = strlen((const char *)kdata.data);
 126         return &kdata;
 127 }
 128 #endif
 129
 130
 131 /**********************************************************
 132  * WRAPPING FUNCTIONS
 133  **********************************************************/
 134
 135 #if defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS)
 136 /* HEIMDAL */
 137
 138 /**
 139  * @brief Stores the address of a 'struct sockaddr_storage' a krb5_address
 140  *
 141  * @param[in]  paddr    A pointer to a 'struct sockaddr_storage to extract the
 142  *                      address from.
 143  *
 144  * @param[out] pkaddr   A Kerberos address to store tha address in.
 145  *
 146  * @return True on success, false if an error occured.
 147  */
 148 bool smb_krb5_sockaddr_to_kaddr(struct sockaddr_storage *paddr,
 149                                 krb5_address *pkaddr)
 150 {
 151         memset(pkaddr, '\0', sizeof(krb5_address));
 152 #if defined(HAVE_IPV6) && defined(KRB5_ADDRESS_INET6)
 153         if (paddr->ss_family == AF_INET6) {
 154                 pkaddr->addr_type = KRB5_ADDRESS_INET6;
 155                 pkaddr->address.length = sizeof(((struct sockaddr_in6 *)paddr)->sin6_addr);
 156                 pkaddr->address.data = (char *)&(((struct sockaddr_in6 *)paddr)->sin6_addr);
 157                 return true;
 158         }
 159 #endif
 160         if (paddr->ss_family == AF_INET) {
 161                 pkaddr->addr_type = KRB5_ADDRESS_INET;
 162                 pkaddr->address.length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
 163                 pkaddr->address.data = (char *)&(((struct sockaddr_in *)paddr)->sin_addr);
 164                 return true;
 165         }
 166         return false;
 167 }
 168 #elif defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS)
 169 /* MIT */
 170
 171 /**
 172  * @brief Stores the address of a 'struct sockaddr_storage' a krb5_address
 173  *
 174  * @param[in]  paddr    A pointer to a 'struct sockaddr_storage to extract the
 175  *                      address from.
 176  *
 177  * @param[in]  pkaddr A Kerberos address to store tha address in.
 178  *
 179  * @return True on success, false if an error occured.
 180  */
 181 bool smb_krb5_sockaddr_to_kaddr(struct sockaddr_storage *paddr,
 182                                 krb5_address *pkaddr)
 183 {
 184         memset(pkaddr, '\0', sizeof(krb5_address));
 185 #if defined(HAVE_IPV6) && defined(ADDRTYPE_INET6)
 186         if (paddr->ss_family == AF_INET6) {
 187                 pkaddr->addrtype = ADDRTYPE_INET6;
 188                 pkaddr->length = sizeof(((struct sockaddr_in6 *)paddr)->sin6_addr);
 189                 pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in6 *)paddr)->sin6_addr);
 190                 return true;
 191         }
 192 #endif
 193         if (paddr->ss_family == AF_INET) {
 194                 pkaddr->addrtype = ADDRTYPE_INET;
 195                 pkaddr->length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
 196                 pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in *)paddr)->sin_addr);
 197                 return true;
 198         }
 199         return false;
 200 }
 201 #else
 202 #error UNKNOWN_ADDRTYPE
 203 #endif
 204
 205 krb5_error_code smb_krb5_mk_error(krb5_context context,
 206                                   krb5_error_code error_code,
 207                                   const char *e_text,
 208                                   krb5_data *e_data,
 209                                   const krb5_principal client,
 210                                   const krb5_principal server,
 211                                   krb5_data *enc_err)
 212 {
 213         krb5_error_code code = EINVAL;
 214 #ifdef SAMBA4_USES_HEIMDAL
 215         code = krb5_mk_error(context,
 216                              error_code,
 217                              e_text,
 218                              e_data,
 219                              client,
 220                              server,
 221                              NULL, /* client_time */
 222                              NULL, /* client_usec */
 223                              enc_err);
 224 #else
 225         krb5_principal unspec_server = NULL;
 226         krb5_error errpkt;
 227
 228         errpkt.ctime = 0;
 229         errpkt.cusec = 0;
 230
 231         code = krb5_us_timeofday(context,
 232                                  &errpkt.stime,
 233                                  &errpkt.susec);
 234         if (code != 0) {
 235                 return code;
 236         }
 237
 238         errpkt.error = error_code;
 239
 240         errpkt.text.length = 0;
 241         if (e_text != NULL) {
 242                 errpkt.text.length = strlen(e_text);
 243                 errpkt.text.data = discard_const_p(char, e_text);
 244         }
 245
 246         errpkt.e_data.magic = KV5M_DATA;
 247         errpkt.e_data.length = 0;
 248         errpkt.e_data.data = NULL;
 249         if (e_data != NULL) {
 250                 errpkt.e_data = *e_data;
 251         }
 252
 253         errpkt.client = client;
 254
 255         if (server != NULL) {
 256                 errpkt.server = server;
 257         } else {
 258                 code = smb_krb5_make_principal(context,
 259                                                &unspec_server,
 260                                                "<unspecified realm>",
 261                                                NULL);
 262                 if (code != 0) {
 263                         return code;
 264                 }
 265                 errpkt.server = unspec_server;
 266         }
 267
 268         code = krb5_mk_error(context,
 269                              &errpkt,
 270                              enc_err);
 271         krb5_free_principal(context, unspec_server);
 272 #endif
 273         return code;
 274 }
 275
 276 /**
 277 * @brief Create a keyblock based on input parameters
 278 *
 279 * @param context        The krb5_context
 280 * @param host_princ     The krb5_principal to use
 281 * @param salt           The optional salt, if omitted, salt is calculated with
 282 *                       the provided principal.
 283 * @param password       The krb5_data containing the password
 284 * @param enctype        The krb5_enctype to use for the keyblock generation
 285 * @param key            The returned krb5_keyblock, caller needs to free with
 286 *                       krb5_free_keyblock().
 287 *
 288 * @return krb5_error_code
 289 */
 290 int smb_krb5_create_key_from_string(krb5_context context,
 291                                     krb5_const_principal host_princ,
 292                                     krb5_data *salt,
 293                                     krb5_data *password,
 294                                     krb5_enctype enctype,
 295                                     krb5_keyblock *key)
 296 {
 297         int ret = 0;
 298
 299         if (host_princ == NULL && salt == NULL) {
 300                 return -1;
 301         }
 302
 303 #if defined(HAVE_KRB5_PRINCIPAL2SALT) && defined(HAVE_KRB5_C_STRING_TO_KEY)
 304 {/* MIT */
 305         krb5_data _salt;
 306
 307         if (salt == NULL) {
 308                 ret = krb5_principal2salt(context, host_princ, &_salt);
 309                 if (ret) {
 310                         DEBUG(1,("krb5_principal2salt failed (%s)\n", error_message(ret)));
 311                         return ret;
 312                 }
 313         } else {
 314                 _salt = *salt;
 315         }
 316         ret = krb5_c_string_to_key(context, enctype, password, &_salt, key);
 317         if (salt == NULL) {
 318                 SAFE_FREE(_salt.data);
 319         }
 320 }
 321 #elif defined(HAVE_KRB5_GET_PW_SALT) && defined(HAVE_KRB5_STRING_TO_KEY_SALT)
 322 {/* Heimdal */
 323         krb5_salt _salt;
 324
 325         if (salt == NULL) {
 326                 ret = krb5_get_pw_salt(context, host_princ, &_salt);
 327                 if (ret) {
 328                         DEBUG(1,("krb5_get_pw_salt failed (%s)\n", error_message(ret)));
 329                         return ret;
 330                 }
 331         } else {
 332                 _salt.saltvalue = *salt;
 333                 _salt.salttype = KRB5_PW_SALT;
 334         }
 335
 336         ret = krb5_string_to_key_salt(context, enctype, (const char *)password->data, _salt, key);
 337         if (salt == NULL) {
 338                 krb5_free_salt(context, _salt);
 339         }
 340 }
 341 #else
 342 #error UNKNOWN_CREATE_KEY_FUNCTIONS
 343 #endif
 344         return ret;
 345 }
 346
 347 /**
 348 * @brief Create a salt for a given principal
 349 *
 350 * @param context        The initialized krb5_context
 351 * @param host_princ     The krb5_principal to create the salt for
 352 * @param psalt          A pointer to a krb5_data struct
 353 *
 354 * caller has to free the contents of psalt with smb_krb5_free_data_contents
 355 * when function has succeeded
 356 *
 357 * @return krb5_error_code, returns 0 on success, error code otherwise
 358 */
 359
 360 int smb_krb5_get_pw_salt(krb5_context context,
 361                          krb5_const_principal host_princ,
 362                          krb5_data *psalt)
 363 #if defined(HAVE_KRB5_GET_PW_SALT)
 364 /* Heimdal */
 365 {
 366         int ret;
 367         krb5_salt salt;
 368
 369         ret = krb5_get_pw_salt(context, host_princ, &salt);
 370         if (ret) {
 371                 return ret;
 372         }
 373
 374         psalt->data = salt.saltvalue.data;
 375         psalt->length = salt.saltvalue.length;
 376
 377         return ret;
 378 }
 379 #elif defined(HAVE_KRB5_PRINCIPAL2SALT)
 380 /* MIT */
 381 {
 382         return krb5_principal2salt(context, host_princ, psalt);
 383 }
 384 #else
 385 #error UNKNOWN_SALT_FUNCTIONS
 386 #endif
 387
 388 #if defined(HAVE_KRB5_GET_PERMITTED_ENCTYPES)
 389 /**
 390  * @brief Get a list of encryption types allowed for session keys
 391  *
 392  * @param[in]  context  The library context
 393  *
 394  * @param[in]  enctypes An allocated, zero-terminated list of encryption types
 395  *
 396  * This function returns an allocated list of encryption types allowed for
 397  * session keys.
 398  *
 399  * Use free() to free the enctypes when it is no longer needed.
 400  *
 401  * @retval 0 Success; otherwise - Kerberos error codes
 402  */
 403 krb5_error_code smb_krb5_get_allowed_etypes(krb5_context context,
 404                                             krb5_enctype **enctypes)
 405 {
 406         return krb5_get_permitted_enctypes(context, enctypes);
 407 }
 408 #elif defined(HAVE_KRB5_GET_DEFAULT_IN_TKT_ETYPES)
 409 krb5_error_code smb_krb5_get_allowed_etypes(krb5_context context,
 410                                             krb5_enctype **enctypes)
 411 {
 412 #ifdef HAVE_KRB5_PDU_NONE_DECL
 413         return krb5_get_default_in_tkt_etypes(context, KRB5_PDU_NONE, enctypes);
 414 #else
 415         return krb5_get_default_in_tkt_etypes(context, enctypes);
 416 #endif
 417 }
 418 #else
 419 #error UNKNOWN_GET_ENCTYPES_FUNCTIONS
 420 #endif
 421
 422
 423 /**
 424  * @brief Convert a string principal name to a Kerberos principal.
 425  *
 426  * @param[in]  context  The library context
 427  *
 428  * @param[in]  name     The principal as a unix charset string.
 429  *
 430  * @param[out] principal The newly allocated principal.
 431  *
 432  * Use krb5_free_principal() to free a principal when it is no longer needed.
 433  *
 434  * @return 0 on success, a Kerberos error code otherwise.
 435  */
 436 krb5_error_code smb_krb5_parse_name(krb5_context context,
 437                                     const char *name,
 438                                     krb5_principal *principal)
 439 {
 440         krb5_error_code ret;
 441         char *utf8_name;
 442         size_t converted_size;
 443         TALLOC_CTX *frame = talloc_stackframe();
 444
 445         if (!push_utf8_talloc(frame, &utf8_name, name, &converted_size)) {
 446                 talloc_free(frame);
 447                 return ENOMEM;
 448         }
 449
 450         ret = krb5_parse_name(context, utf8_name, principal);
 451         TALLOC_FREE(frame);
 452         return ret;
 453 }
 454
 455 /**
 456  * @brief Convert a Kerberos principal structure to a string representation.
 457  *
 458  * The resulting string representation will be a unix charset name and is
 459  * talloc'ed.
 460  *
 461  * @param[in]  mem_ctx  The talloc context to allocate memory on.
 462  *
 463  * @param[in]  context  The library context.
 464  *
 465  * @param[in]  principal The principal.
 466  *
 467  * @param[out] unix_name A string representation of the princpial name as with
 468  *                       unix charset.
 469  *
 470  * Use talloc_free() to free the string representation if it is no longer
 471  * needed.
 472  *
 473  * @return 0 on success, a Kerberos error code otherwise.
 474  */
 475 krb5_error_code smb_krb5_unparse_name(TALLOC_CTX *mem_ctx,
 476                                       krb5_context context,
 477                                       krb5_const_principal principal,
 478                                       char **unix_name)
 479 {
 480         krb5_error_code ret;
 481         char *utf8_name;
 482         size_t converted_size;
 483
 484         *unix_name = NULL;
 485         ret = krb5_unparse_name(context, principal, &utf8_name);
 486         if (ret) {
 487                 return ret;
 488         }
 489
 490         if (!pull_utf8_talloc(mem_ctx, unix_name, utf8_name, &converted_size)) {
 491                 krb5_free_unparsed_name(context, utf8_name);
 492                 return ENOMEM;
 493         }
 494         krb5_free_unparsed_name(context, utf8_name);
 495         return 0;
 496 }
 497
 498 /**
 499  * @brief Free the contents of a krb5_data structure and zero the data field.
 500  *
 501  * @param[in]  context  The krb5 context
 502  *
 503  * @param[in]  pdata    The data structure to free contents of
 504  *
 505  * This function frees the contents, not the structure itself.
 506  */
 507 void smb_krb5_free_data_contents(krb5_context context, krb5_data *pdata)
 508 {
 509 #if defined(HAVE_KRB5_FREE_DATA_CONTENTS)
 510         if (pdata->data) {
 511                 krb5_free_data_contents(context, pdata);
 512         }
 513 #elif defined(HAVE_KRB5_DATA_FREE)
 514         krb5_data_free(context, pdata);
 515 #else
 516         SAFE_FREE(pdata->data);
 517 #endif
 518 }
 519
 520 /*
 521  * @brief copy a buffer into a krb5_data struct
 522  *
 523  * @param[in] p                 The krb5_data
 524  * @param[in] data              The data to copy
 525  * @param[in] length            The length of the data to copy
 526  * @return krb5_error_code
 527  *
 528  * Caller has to free krb5_data with smb_krb5_free_data_contents().
 529  */
 530 krb5_error_code smb_krb5_copy_data_contents(krb5_data *p,
 531                                             const void *data,
 532                                             size_t len)
 533 {
 534 #if defined(HAVE_KRB5_DATA_COPY)
 535         return krb5_data_copy(p, data, len);
 536 #else
 537         if (len) {
 538                 p->data = malloc(len);
 539                 if (p->data == NULL) {
 540                         return ENOMEM;
 541                 }
 542                 memmove(p->data, data, len);
 543         } else {
 544                 p->data = NULL;
 545         }
 546         p->length = len;
 547         p->magic = KV5M_DATA;
 548         return 0;
 549 #endif
 550 }
 551
 552 bool smb_krb5_get_smb_session_key(TALLOC_CTX *mem_ctx,
 553                                   krb5_context context,
 554                                   krb5_auth_context auth_context,
 555                                   DATA_BLOB *session_key,
 556                                   bool remote)
 557 {
 558         krb5_keyblock *skey = NULL;
 559         krb5_error_code err = 0;
 560         bool ret = false;
 561
 562         if (remote) {
 563 #ifdef HAVE_KRB5_AUTH_CON_GETRECVSUBKEY
 564                 err = krb5_auth_con_getrecvsubkey(context,
 565                                                   auth_context,
 566                                                   &skey);
 567 #else /* HAVE_KRB5_AUTH_CON_GETRECVSUBKEY */
 568                 err = krb5_auth_con_getremotesubkey(context,
 569                                                     auth_context, &skey);
 570 #endif /* HAVE_KRB5_AUTH_CON_GETRECVSUBKEY */
 571         } else {
 572 #ifdef HAVE_KRB5_AUTH_CON_GETSENDSUBKEY
 573                 err = krb5_auth_con_getsendsubkey(context,
 574                                                   auth_context,
 575                                                   &skey);
 576 #else /* HAVE_KRB5_AUTH_CON_GETSENDSUBKEY */
 577                 err = krb5_auth_con_getlocalsubkey(context,
 578                                                    auth_context, &skey);
 579 #endif /* HAVE_KRB5_AUTH_CON_GETSENDSUBKEY */
 580         }
 581
 582         if (err || skey == NULL) {
 583                 DEBUG(10, ("KRB5 error getting session key %d\n", err));
 584                 goto done;
 585         }
 586
 587         DEBUG(10, ("Got KRB5 session key of length %d\n",
 588                    (int)KRB5_KEY_LENGTH(skey)));
 589
 590         *session_key = data_blob_talloc(mem_ctx,
 591                                          KRB5_KEY_DATA(skey),
 592                                          KRB5_KEY_LENGTH(skey));
 593         dump_data_pw("KRB5 Session Key:\n",
 594                      session_key->data,
 595                      session_key->length);
 596
 597         ret = true;
 598
 599 done:
 600         if (skey) {
 601                 krb5_free_keyblock(context, skey);
 602         }
 603
 604         return ret;
 605 }
 606
 607
 608 /**
 609  * @brief Get talloced string component of a principal
 610  *
 611  * @param[in] mem_ctx           The TALLOC_CTX
 612  * @param[in] context           The krb5_context
 613  * @param[in] principal         The principal
 614  * @param[in] component         The component
 615  * @return string component
 616  *
 617  * Caller must talloc_free if the return value is not NULL.
 618  *
 619  */
 620 char *smb_krb5_principal_get_comp_string(TALLOC_CTX *mem_ctx,
 621                                          krb5_context context,
 622                                          krb5_const_principal principal,
 623                                          unsigned int component)
 624 {
 625 #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING)
 626         return talloc_strdup(mem_ctx, krb5_principal_get_comp_string(context, principal, component));
 627 #else
 628         krb5_data *data;
 629
 630         if (component >= krb5_princ_size(context, principal)) {
 631                 return NULL;
 632         }
 633
 634         data = krb5_princ_component(context, principal, component);
 635         if (data == NULL) {
 636                 return NULL;
 637         }
 638
 639         return talloc_strndup(mem_ctx, data->data, data->length);
 640 #endif
 641 }
 642
 643 /**
 644  * @brief
 645  *
 646  * @param[in]  ccache_string A string pointing to the cache to renew the ticket
 647  *                           (e.g. FILE:/tmp/krb5cc_0) or NULL. If the principal
 648  *                           ccache has not been specified, the default ccache
 649  *                           will be used.
 650  *
 651  * @param[in]  client_string The client principal string (e.g. user@SAMBA.SITE)
 652  *                           or NULL. If the principal string has not been
 653  *                           specified, the principal from the ccache will be
 654  *                           retrieved.
 655  *
 656  * @param[in]  service_string The service ticket string
 657  *                            (e.g. krbtgt/SAMBA.SITE@SAMBA.SITE) or NULL. If
 658  *                            the sevice ticket is specified, it is parsed (
 659  *                            with the realm part ignored) and used as the
 660  *                            server principal of the credential. Otherwise
 661  *                            the ticket-granting service is used.
 662  *
 663  * @param[in]  expire_time    A pointer to store the credentials end time or
 664  *                            NULL.
 665  *
 666  * @return 0 on Succes, a Kerberos error code otherwise.
 667  */
 668 krb5_error_code smb_krb5_renew_ticket(const char *ccache_string,
 669                                       const char *client_string,
 670                                       const char *service_string,
 671                                       time_t *expire_time)
 672 {
 673         krb5_error_code ret;
 674         krb5_context context = NULL;
 675         krb5_ccache ccache = NULL;
 676         krb5_principal client = NULL;
 677         krb5_creds creds, creds_in;
 678
 679         ZERO_STRUCT(creds);
 680         ZERO_STRUCT(creds_in);
 681
 682         initialize_krb5_error_table();
 683         ret = krb5_init_context(&context);
 684         if (ret) {
 685                 goto done;
 686         }
 687
 688         if (!ccache_string) {
 689                 ccache_string = krb5_cc_default_name(context);
 690         }
 691
 692         if (!ccache_string) {
 693                 ret = EINVAL;
 694                 goto done;
 695         }
 696
 697         DEBUG(10,("smb_krb5_renew_ticket: using %s as ccache\n", ccache_string));
 698
 699         /* FIXME: we should not fall back to defaults */
 700         ret = krb5_cc_resolve(context, discard_const_p(char, ccache_string), &ccache);
 701         if (ret) {
 702                 goto done;
 703         }
 704
 705         if (client_string) {
 706                 ret = smb_krb5_parse_name(context, client_string, &client);
 707                 if (ret) {
 708                         goto done;
 709                 }
 710         } else {
 711                 ret = krb5_cc_get_principal(context, ccache, &client);
 712                 if (ret) {
 713                         goto done;
 714                 }
 715         }
 716
 717         ret = krb5_get_renewed_creds(context, &creds, client, ccache, discard_const_p(char, service_string));
 718         if (ret) {
 719                 DEBUG(10,("smb_krb5_renew_ticket: krb5_get_kdc_cred failed: %s\n", error_message(ret)));
 720                 goto done;
 721         }
 722
 723         /* hm, doesn't that create a new one if the old one wasn't there? - Guenther */
 724         ret = krb5_cc_initialize(context, ccache, client);
 725         if (ret) {
 726                 goto done;
 727         }
 728
 729         ret = krb5_cc_store_cred(context, ccache, &creds);
 730
 731         if (expire_time) {
 732                 *expire_time = (time_t) creds.times.endtime;
 733         }
 734
 735 done:
 736         krb5_free_cred_contents(context, &creds_in);
 737         krb5_free_cred_contents(context, &creds);
 738
 739         if (client) {
 740                 krb5_free_principal(context, client);
 741         }
 742         if (ccache) {
 743                 krb5_cc_close(context, ccache);
 744         }
 745         if (context) {
 746                 krb5_free_context(context);
 747         }
 748
 749         return ret;
 750 }
 751
 752 /**
 753  * @brief Free the data stored in an smb_krb5_addresses structure.
 754  *
 755  * @param[in]  context  The library context
 756  *
 757  * @param[in]  addr     The address structure to free.
 758  *
 759  * @return 0 on success, a Kerberos error code otherwise.
 760  */
 761 krb5_error_code smb_krb5_free_addresses(krb5_context context,
 762                                         smb_krb5_addresses *addr)
 763 {
 764         krb5_error_code ret = 0;
 765         if (addr == NULL) {
 766                 return ret;
 767         }
 768 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
 769         krb5_free_addresses(context, addr->addrs);
 770 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
 771         ret = krb5_free_addresses(context, addr->addrs);
 772         SAFE_FREE(addr->addrs);
 773 #endif
 774         SAFE_FREE(addr);
 775         addr = NULL;
 776         return ret;
 777 }
 778
 779 #define MAX_NETBIOSNAME_LEN 16
 780
 781 /**
 782  * @brief Add a netbios name to the array of addresses
 783  *
 784  * @param[in]  kerb_addr A pointer to the smb_krb5_addresses to add the
 785  *                       netbios name to.
 786  *
 787  * @param[in]  netbios_name The netbios name to add.
 788  *
 789  * @return 0 on success, a Kerberos error code otherwise.
 790  */
 791 krb5_error_code smb_krb5_gen_netbios_krb5_address(smb_krb5_addresses **kerb_addr,
 792                                                    const char *netbios_name)
 793 {
 794         krb5_error_code ret = 0;
 795         char buf[MAX_NETBIOSNAME_LEN];
 796         int len;
 797 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
 798         krb5_address **addrs = NULL;
 799 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
 800         krb5_addresses *addrs = NULL;
 801 #endif
 802
 803         *kerb_addr = (smb_krb5_addresses *)SMB_MALLOC(sizeof(smb_krb5_addresses));
 804         if (*kerb_addr == NULL) {
 805                 return ENOMEM;
 806         }
 807
 808         /* temporarily duplicate put_name() code here to avoid dependency
 809          * issues for a 5 lines function */
 810         len = strlen(netbios_name);
 811         memcpy(buf, netbios_name,
 812                 (len < MAX_NETBIOSNAME_LEN) ? len : MAX_NETBIOSNAME_LEN - 1);
 813         if (len < MAX_NETBIOSNAME_LEN - 1) {
 814                 memset(buf + len, ' ', MAX_NETBIOSNAME_LEN - 1 - len);
 815         }
 816         buf[MAX_NETBIOSNAME_LEN - 1] = 0x20;
 817
 818 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
 819         {
 820                 int num_addr = 2;
 821
 822                 addrs = (krb5_address **)SMB_MALLOC(sizeof(krb5_address *) * num_addr);
 823                 if (addrs == NULL) {
 824                         SAFE_FREE(*kerb_addr);
 825                         return ENOMEM;
 826                 }
 827
 828                 memset(addrs, 0, sizeof(krb5_address *) * num_addr);
 829
 830                 addrs[0] = (krb5_address *)SMB_MALLOC(sizeof(krb5_address));
 831                 if (addrs[0] == NULL) {
 832                         SAFE_FREE(addrs);
 833                         SAFE_FREE(*kerb_addr);
 834                         return ENOMEM;
 835                 }
 836
 837                 addrs[0]->magic = KV5M_ADDRESS;
 838                 addrs[0]->addrtype = KRB5_ADDR_NETBIOS;
 839                 addrs[0]->length = MAX_NETBIOSNAME_LEN;
 840                 addrs[0]->contents = (unsigned char *)SMB_MALLOC(addrs[0]->length);
 841                 if (addrs[0]->contents == NULL) {
 842                         SAFE_FREE(addrs[0]);
 843                         SAFE_FREE(addrs);
 844                         SAFE_FREE(*kerb_addr);
 845                         return ENOMEM;
 846                 }
 847
 848                 memcpy(addrs[0]->contents, buf, addrs[0]->length);
 849
 850                 addrs[1] = NULL;
 851         }
 852 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
 853         {
 854                 addrs = (krb5_addresses *)SMB_MALLOC(sizeof(krb5_addresses));
 855                 if (addrs == NULL) {
 856                         SAFE_FREE(*kerb_addr);
 857                         return ENOMEM;
 858                 }
 859
 860                 memset(addrs, 0, sizeof(krb5_addresses));
 861
 862                 addrs->len = 1;
 863                 addrs->val = (krb5_address *)SMB_MALLOC(sizeof(krb5_address));
 864                 if (addrs->val == NULL) {
 865                         SAFE_FREE(addrs);
 866                         SAFE_FREE(kerb_addr);
 867                         return ENOMEM;
 868                 }
 869
 870                 addrs->val[0].addr_type = KRB5_ADDR_NETBIOS;
 871                 addrs->val[0].address.length = MAX_NETBIOSNAME_LEN;
 872                 addrs->val[0].address.data = (unsigned char *)SMB_MALLOC(addrs->val[0].address.length);
 873                 if (addrs->val[0].address.data == NULL) {
 874                         SAFE_FREE(addrs->val);
 875                         SAFE_FREE(addrs);
 876                         SAFE_FREE(*kerb_addr);
 877                         return ENOMEM;
 878                 }
 879
 880                 memcpy(addrs->val[0].address.data, buf, addrs->val[0].address.length);
 881         }
 882 #else
 883 #error UNKNOWN_KRB5_ADDRESS_FORMAT
 884 #endif
 885         (*kerb_addr)->addrs = addrs;
 886
 887         return ret;
 888 }
 889
 890 /**
 891  * @brief Get the enctype from a key table entry
 892  *
 893  * @param[in]  kt_entry Key table entry to get the enctype from.
 894  *
 895  * @return The enctype from the entry.
 896  */
 897 krb5_enctype smb_krb5_kt_get_enctype_from_entry(krb5_keytab_entry *kt_entry)
 898 {
 899         return KRB5_KEY_TYPE(KRB5_KT_KEY(kt_entry));
 900 }
 901
 902 /**
 903  * @brief Free the contents of a key table entry.
 904  *
 905  * @param[in]  context The library context.
 906  *
 907  * @param[in]  kt_entry The key table entry to free the contents of.
 908  *
 909  * @return 0 on success, a Kerberos error code otherwise.
 910  *
 911  * The pointer itself is not freed.
 912  */
 913 krb5_error_code smb_krb5_kt_free_entry(krb5_context context,
 914                                         krb5_keytab_entry *kt_entry)
 915 {
 916 /* Try krb5_free_keytab_entry_contents first, since
 917  * MIT Kerberos >= 1.7 has both krb5_free_keytab_entry_contents and
 918  * krb5_kt_free_entry but only has a prototype for the first, while the
 919  * second is considered private.
 920  */
 921 #if defined(HAVE_KRB5_FREE_KEYTAB_ENTRY_CONTENTS)
 922         return krb5_free_keytab_entry_contents(context, kt_entry);
 923 #elif defined(HAVE_KRB5_KT_FREE_ENTRY)
 924         return krb5_kt_free_entry(context, kt_entry);
 925 #else
 926 #error UNKNOWN_KT_FREE_FUNCTION
 927 #endif
 928 }
 929
 930
 931 /**
 932  * @brief Convert an encryption type to a string.
 933  *
 934  * @param[in]  context The library context.
 935  *
 936  * @param[in]  enctype The encryption type.
 937  *
 938  * @param[in]  etype_s A pointer to store the allocated encryption type as a
 939  *                     string.
 940  *
 941  * @return 0 on success, a Kerberos error code otherwise.
 942  *
 943  * The caller needs to free the allocated string etype_s.
 944  */
 945 krb5_error_code smb_krb5_enctype_to_string(krb5_context context,
 946                                            krb5_enctype enctype,
 947                                            char **etype_s)
 948 {
 949 #ifdef HAVE_KRB5_ENCTYPE_TO_STRING_WITH_KRB5_CONTEXT_ARG
 950         return krb5_enctype_to_string(context, enctype, etype_s); /* Heimdal */
 951 #elif defined(HAVE_KRB5_ENCTYPE_TO_STRING_WITH_SIZE_T_ARG)
 952         char buf[256];
 953         krb5_error_code ret = krb5_enctype_to_string(enctype, buf, 256); /* MIT */
 954         if (ret) {
 955                 return ret;
 956         }
 957         *etype_s = SMB_STRDUP(buf);
 958         if (!*etype_s) {
 959                 return ENOMEM;
 960         }
 961         return ret;
 962 #else
 963 #error UNKNOWN_KRB5_ENCTYPE_TO_STRING_FUNCTION
 964 #endif
 965 }
 966
 967 /* This MAX_NAME_LEN is a constant defined in krb5.h */
 968 #ifndef MAX_KEYTAB_NAME_LEN
 969 #define MAX_KEYTAB_NAME_LEN 1100
 970 #endif
 971
 972 /**
 973  * @brief Open a key table readonly or with readwrite access.
 974  *
 975  * Allows to use a different keytab than the default one using a relative
 976  * path to the keytab.
 977  *
 978  * @param[in]  context  The library context
 979  *
 980  * @param[in]  keytab_name_req The path to the key table.
 981  *
 982  * @param[in]  write_access Open with readwrite access.
 983  *
 984  * @param[in]  keytab A pointer o the opended key table.
 985  *
 986  * The keytab pointer should be freed using krb5_kt_close().
 987  *
 988  * @return 0 on success, a Kerberos error code otherwise.
 989  */
 990 krb5_error_code smb_krb5_kt_open_relative(krb5_context context,
 991                                           const char *keytab_name_req,
 992                                           bool write_access,
 993                                           krb5_keytab *keytab)
 994 {
 995         krb5_error_code ret = 0;
 996         TALLOC_CTX *mem_ctx;
 997         char keytab_string[MAX_KEYTAB_NAME_LEN];
 998         char *kt_str = NULL;
 999         bool found_valid_name = false;
1000         const char *pragma = "FILE";
1001         const char *tmp = NULL;
1002
1003         if (!write_access && !keytab_name_req) {
1004                 /* caller just wants to read the default keytab readonly, so be it */
1005                 return krb5_kt_default(context, keytab);
1006         }
1007
1008         mem_ctx = talloc_init("smb_krb5_open_keytab");
1009         if (!mem_ctx) {
1010                 return ENOMEM;
1011         }
1012
1013 #ifdef HAVE_WRFILE_KEYTAB
1014         if (write_access) {
1015                 pragma = "WRFILE";
1016         }
1017 #endif
1018
1019         if (keytab_name_req) {
1020
1021                 if (strlen(keytab_name_req) > MAX_KEYTAB_NAME_LEN) {
1022                         ret = KRB5_CONFIG_NOTENUFSPACE;
1023                         goto out;
1024                 }
1025
1026                 if ((strncmp(keytab_name_req, "WRFILE:", 7) == 0) ||
1027                     (strncmp(keytab_name_req, "FILE:", 5) == 0)) {
1028                         tmp = keytab_name_req;
1029                         goto resolve;
1030                 }
1031
1032                 tmp = talloc_asprintf(mem_ctx, "%s:%s", pragma, keytab_name_req);
1033                 if (!tmp) {
1034                         ret = ENOMEM;
1035                         goto out;
1036                 }
1037
1038                 goto resolve;
1039         }
1040
1041         /* we need to handle more complex keytab_strings, like:
1042          * "ANY:FILE:/etc/krb5.keytab,krb4:/etc/srvtab" */
1043
1044         ret = krb5_kt_default_name(context, &keytab_string[0], MAX_KEYTAB_NAME_LEN - 2);
1045         if (ret) {
1046                 goto out;
1047         }
1048
1049         DEBUG(10,("smb_krb5_open_keytab: krb5_kt_default_name returned %s\n", keytab_string));
1050
1051         tmp = talloc_strdup(mem_ctx, keytab_string);
1052         if (!tmp) {
1053                 ret = ENOMEM;
1054                 goto out;
1055         }
1056
1057         if (strncmp(tmp, "ANY:", 4) == 0) {
1058                 tmp += 4;
1059         }
1060
1061         memset(&keytab_string, '\0', sizeof(keytab_string));
1062
1063         while (next_token_talloc(mem_ctx, &tmp, &kt_str, ",")) {
1064                 if (strncmp(kt_str, "WRFILE:", 7) == 0) {
1065                         found_valid_name = true;
1066                         tmp = kt_str;
1067                         tmp += 7;
1068                 }
1069
1070                 if (strncmp(kt_str, "FILE:", 5) == 0) {
1071                         found_valid_name = true;
1072                         tmp = kt_str;
1073                         tmp += 5;
1074                 }
1075
1076                 if (tmp[0] == '/') {
1077                         /* Treat as a FILE: keytab definition. */
1078                         found_valid_name = true;
1079                 }
1080
1081                 if (found_valid_name) {
1082                         if (tmp[0] != '/') {
1083                                 ret = KRB5_KT_BADNAME;
1084                                 goto out;
1085                         }
1086
1087                         tmp = talloc_asprintf(mem_ctx, "%s:%s", pragma, tmp);
1088                         if (!tmp) {
1089                                 ret = ENOMEM;
1090                                 goto out;
1091                         }
1092                         break;
1093                 }
1094         }
1095
1096         if (!found_valid_name) {
1097                 ret = KRB5_KT_UNKNOWN_TYPE;
1098                 goto out;
1099         }
1100
1101 resolve:
1102         DEBUG(10,("smb_krb5_open_keytab: resolving: %s\n", tmp));
1103         ret = krb5_kt_resolve(context, tmp, keytab);
1104
1105 out:
1106         TALLOC_FREE(mem_ctx);
1107         return ret;
1108 }
1109
1110 /**
1111  * @brief Open a key table readonly or with readwrite access.
1112  *
1113  * Allows to use a different keytab than the default one. The path needs to be
1114  * an absolute path or an error will be returned.
1115  *
1116  * @param[in]  context  The library context
1117  *
1118  * @param[in]  keytab_name_req The path to the key table.
1119  *
1120  * @param[in]  write_access Open with readwrite access.
1121  *
1122  * @param[in]  keytab A pointer o the opended key table.
1123  *
1124  * The keytab pointer should be freed using krb5_kt_close().
1125  *
1126  * @return 0 on success, a Kerberos error code otherwise.
1127  */
1128 krb5_error_code smb_krb5_kt_open(krb5_context context,
1129                                  const char *keytab_name_req,
1130                                  bool write_access,
1131                                  krb5_keytab *keytab)
1132 {
1133         int cmp;
1134
1135         if (keytab_name_req == NULL) {
1136                 return KRB5_KT_BADNAME;
1137         }
1138
1139         if (keytab_name_req[0] == '/') {
1140                 goto open_keytab;
1141         }
1142
1143         cmp = strncmp(keytab_name_req, "FILE:/", 6);
1144         if (cmp == 0) {
1145                 goto open_keytab;
1146         }
1147
1148         cmp = strncmp(keytab_name_req, "WRFILE:/", 8);
1149         if (cmp == 0) {
1150                 goto open_keytab;
1151         }
1152
1153         return KRB5_KT_BADNAME;
1154
1155 open_keytab:
1156         return smb_krb5_kt_open_relative(context,
1157                                          keytab_name_req,
1158                                          write_access,
1159                                          keytab);
1160 }
1161
1162 /**
1163  * @brief Get a key table name.
1164  *
1165  * @param[in]  mem_ctx The talloc context to use for allocation.
1166  *
1167  * @param[in]  context The library context.
1168  *
1169  * @param[in]  keytab The key table to get the name from.
1170  *
1171  * @param[in]  keytab_name A talloc'ed string of the key table name.
1172  *
1173  * The talloc'ed name string needs to be freed with talloc_free().
1174  *
1175  * @return 0 on success, a Kerberos error code otherwise.
1176  */
1177 krb5_error_code smb_krb5_kt_get_name(TALLOC_CTX *mem_ctx,
1178                                      krb5_context context,
1179                                      krb5_keytab keytab,
1180                                      const char **keytab_name)
1181 {
1182         char keytab_string[MAX_KEYTAB_NAME_LEN];
1183         krb5_error_code ret = 0;
1184
1185         ret = krb5_kt_get_name(context, keytab,
1186                                keytab_string, MAX_KEYTAB_NAME_LEN - 2);
1187         if (ret) {
1188                 return ret;
1189         }
1190
1191         *keytab_name = talloc_strdup(mem_ctx, keytab_string);
1192         if (!*keytab_name) {
1193                 return ENOMEM;
1194         }
1195
1196         return ret;
1197 }
1198
1199 /**
1200  * @brief Seek and delete old entries in a keytab based on the passed
1201  *        principal.
1202  *
1203  * @param[in]  context       The KRB5 context to use.
1204  *
1205  * @param[in]  keytab        The keytab to operate on.
1206  *
1207  * @param[in]  kvno          The kvnco to use.
1208  *
1209  * @param[in]  princ_s       The principal as a string to search for.
1210  *
1211  * @param[in]  princ         The principal as a krb5_principal to search for.
1212  *
1213  * @param[in]  flush         Weather to flush the complete keytab.
1214  *
1215  * @param[in]  keep_old_entries Keep the entry with the previous kvno.
1216  *
1217  * @retval 0 on Sucess
1218  *
1219  * @return An appropriate KRB5 error code.
1220  */
1221 krb5_error_code smb_krb5_kt_seek_and_delete_old_entries(krb5_context context,
1222                                                         krb5_keytab keytab,
1223                                                         krb5_kvno kvno,
1224                                                         krb5_enctype enctype,
1225                                                         const char *princ_s,
1226                                                         krb5_principal princ,
1227                                                         bool flush,
1228                                                         bool keep_old_entries)
1229 {
1230         krb5_error_code ret;
1231         krb5_kt_cursor cursor;
1232         krb5_kt_cursor zero_csr;
1233         krb5_keytab_entry kt_entry;
1234         krb5_keytab_entry zero_kt_entry;
1235         char *ktprinc = NULL;
1236         krb5_kvno old_kvno = kvno - 1;
1237         TALLOC_CTX *tmp_ctx;
1238
1239         ZERO_STRUCT(cursor);
1240         ZERO_STRUCT(zero_csr);
1241         ZERO_STRUCT(kt_entry);
1242         ZERO_STRUCT(zero_kt_entry);
1243
1244         ret = krb5_kt_start_seq_get(context, keytab, &cursor);
1245         if (ret == KRB5_KT_END || ret == ENOENT ) {
1246                 /* no entries */
1247                 return 0;
1248         }
1249
1250         tmp_ctx = talloc_new(NULL);
1251         if (tmp_ctx == NULL) {
1252                 return ENOMEM;
1253         }
1254
1255         DEBUG(3, (__location__ ": Will try to delete old keytab entries\n"));
1256         while (!krb5_kt_next_entry(context, keytab, &kt_entry, &cursor)) {
1257                 bool name_ok = false;
1258                 krb5_enctype kt_entry_enctype =
1259                         smb_krb5_kt_get_enctype_from_entry(&kt_entry);
1260
1261                 if (!flush && (princ_s != NULL)) {
1262                         ret = smb_krb5_unparse_name(tmp_ctx, context,
1263                                                     kt_entry.principal,
1264                                                     &ktprinc);
1265                         if (ret) {
1266                                 DEBUG(1, (__location__
1267                                           ": smb_krb5_unparse_name failed "
1268                                           "(%s)\n", error_message(ret)));
1269                                 goto out;
1270                         }
1271
1272 #ifdef HAVE_KRB5_KT_COMPARE
1273                         name_ok = krb5_kt_compare(context, &kt_entry,
1274                                                   princ, 0, 0);
1275 #else
1276                         name_ok = (strcmp(ktprinc, princ_s) == 0);
1277 #endif
1278
1279                         if (!name_ok) {
1280                                 DEBUG(10, (__location__ ": ignoring keytab "
1281                                            "entry principal %s, kvno = %d\n",
1282                                            ktprinc, kt_entry.vno));
1283
1284                                 /* Not a match,
1285                                  * just free this entry and continue. */
1286                                 ret = smb_krb5_kt_free_entry(context,
1287                                                              &kt_entry);
1288                                 ZERO_STRUCT(kt_entry);
1289                                 if (ret) {
1290                                         DEBUG(1, (__location__
1291                                                   ": smb_krb5_kt_free_entry "
1292                                                   "failed (%s)\n",
1293                                                   error_message(ret)));
1294                                         goto out;
1295                                 }
1296
1297                                 TALLOC_FREE(ktprinc);
1298                                 continue;
1299                         }
1300
1301                         TALLOC_FREE(ktprinc);
1302                 }
1303
1304                 /*------------------------------------------------------------
1305                  * Save the entries with kvno - 1. This is what microsoft does
1306                  * to allow people with existing sessions that have kvno - 1
1307                  * to still work. Otherwise, when the password for the machine
1308                  * changes, all kerberizied sessions will 'break' until either
1309                  * the client reboots or the client's session key expires and
1310                  * they get a new session ticket with the new kvno.
1311                  * Some keytab files only store the kvno in 8bits, limit
1312                  * the compare accordingly.
1313                  */
1314
1315                 if (!flush && ((kt_entry.vno & 0xff) == (old_kvno & 0xff))) {
1316                         DEBUG(5, (__location__ ": Saving previous (kvno %d) "
1317                                   "entry for principal: %s.\n",
1318                                   old_kvno, princ_s));
1319                         continue;
1320                 }
1321
1322                 if (keep_old_entries) {
1323                         DEBUG(5, (__location__ ": Saving old (kvno %d) "
1324                                   "entry for principal: %s.\n",
1325                                   kvno, princ_s));
1326                         continue;
1327                 }
1328
1329                 if (!flush &&
1330                     (kt_entry.vno == kvno) &&
1331                     (kt_entry_enctype != enctype))
1332                 {
1333                         DEBUG(5, (__location__ ": Saving entry with kvno [%d] "
1334                                   "enctype [%d] for principal: %s.\n",
1335                                   kvno, kt_entry_enctype, princ_s));
1336                         continue;
1337                 }
1338
1339                 DEBUG(5, (__location__ ": Found old entry for principal: %s "
1340                           "(kvno %d) - trying to remove it.\n",
1341                           princ_s, kt_entry.vno));
1342
1343                 ret = krb5_kt_end_seq_get(context, keytab, &cursor);
1344                 ZERO_STRUCT(cursor);
1345                 if (ret) {
1346                         DEBUG(1, (__location__ ": krb5_kt_end_seq_get() "
1347                                   "failed (%s)\n", error_message(ret)));
1348                         goto out;
1349                 }
1350                 ret = krb5_kt_remove_entry(context, keytab, &kt_entry);
1351                 if (ret) {
1352                         DEBUG(1, (__location__ ": krb5_kt_remove_entry() "
1353                                   "failed (%s)\n", error_message(ret)));
1354                         goto out;
1355                 }
1356
1357                 DEBUG(5, (__location__ ": removed old entry for principal: "
1358                           "%s (kvno %d).\n", princ_s, kt_entry.vno));
1359
1360                 ret = krb5_kt_start_seq_get(context, keytab, &cursor);
1361                 if (ret) {
1362                         DEBUG(1, (__location__ ": krb5_kt_start_seq() failed "
1363                                   "(%s)\n", error_message(ret)));
1364                         goto out;
1365                 }
1366                 ret = smb_krb5_kt_free_entry(context, &kt_entry);
1367                 ZERO_STRUCT(kt_entry);
1368                 if (ret) {
1369                         DEBUG(1, (__location__ ": krb5_kt_remove_entry() "
1370                                   "failed (%s)\n", error_message(ret)));
1371                         goto out;
1372                 }
1373         }
1374
1375 out:
1376         talloc_free(tmp_ctx);
1377         if (memcmp(&zero_kt_entry, &kt_entry, sizeof(krb5_keytab_entry))) {
1378                 smb_krb5_kt_free_entry(context, &kt_entry);
1379         }
1380         if (memcmp(&cursor, &zero_csr, sizeof(krb5_kt_cursor)) != 0) {
1381                 krb5_kt_end_seq_get(context, keytab, &cursor);
1382         }
1383         return ret;
1384 }
1385
1386 /**
1387  * @brief Add a keytab entry for the given principal
1388  *
1389  * @param[in]  context       The krb5 context to use.
1390  *
1391  * @param[in]  keytab        The keytab to add the entry to.
1392  *
1393  * @param[in]  kvno          The kvno to use.
1394  *
1395  * @param[in]  princ_s       The principal as a string.
1396  *
1397  * @param[in]  salt_principal The salt principal to salt the password with.
1398  *                            Only needed for keys which support salting.
1399  *                            If no salt is used set no_salt to false and
1400  *                            pass NULL here.
1401  *
1402  * @param[in]  enctype        The encryption type of the keytab entry.
1403  *
1404  * @param[in]  password       The password of the keytab entry.
1405  *
1406  * @param[in]  no_salt        If the password should not be salted. Normally
1407  *                            this is only set to false for encryption types
1408  *                            which do not support salting like RC4.
1409  *
1410  * @param[in]  keep_old_entries Wether to keep or delte old keytab entries.
1411  *
1412  * @retval 0 on Success
1413  *
1414  * @return A corresponding KRB5 error code.
1415  *
1416  * @see smb_krb5_kt_open()
1417  */
1418 krb5_error_code smb_krb5_kt_add_entry(krb5_context context,
1419                                       krb5_keytab keytab,
1420                                       krb5_kvno kvno,
1421                                       const char *princ_s,
1422                                       const char *salt_principal,
1423                                       krb5_enctype enctype,
1424                                       krb5_data *password,
1425                                       bool no_salt,
1426                                       bool keep_old_entries)
1427 {
1428         krb5_error_code ret;
1429         krb5_keytab_entry kt_entry;
1430         krb5_principal princ = NULL;
1431         krb5_keyblock *keyp;
1432
1433         ZERO_STRUCT(kt_entry);
1434
1435         ret = smb_krb5_parse_name(context, princ_s, &princ);
1436         if (ret) {
1437                 DEBUG(1, (__location__ ": smb_krb5_parse_name(%s) "
1438                           "failed (%s)\n", princ_s, error_message(ret)));
1439                 goto out;
1440         }
1441
1442         /* Seek and delete old keytab entries */
1443         ret = smb_krb5_kt_seek_and_delete_old_entries(context,
1444                                                       keytab,
1445                                                       kvno,
1446                                                       enctype,
1447                                                       princ_s,
1448                                                       princ,
1449                                                       false,
1450                                                       keep_old_entries);
1451         if (ret) {
1452                 goto out;
1453         }
1454
1455         /* If we get here, we have deleted all the old entries with kvno's
1456          * not equal to the current kvno-1. */
1457
1458         keyp = KRB5_KT_KEY(&kt_entry);
1459
1460         if (no_salt) {
1461                 KRB5_KEY_DATA(keyp) = (KRB5_KEY_DATA_CAST *)SMB_MALLOC(password->length);
1462                 if (KRB5_KEY_DATA(keyp) == NULL) {
1463                         ret = ENOMEM;
1464                         goto out;
1465                 }
1466                 memcpy(KRB5_KEY_DATA(keyp), password->data, password->length);
1467                 KRB5_KEY_LENGTH(keyp) = password->length;
1468                 KRB5_KEY_TYPE(keyp) = enctype;
1469         } else {
1470                 krb5_principal salt_princ = NULL;
1471
1472                 /* Now add keytab entries for all encryption types */
1473                 ret = smb_krb5_parse_name(context, salt_principal, &salt_princ);
1474                 if (ret) {
1475                         DBG_WARNING("krb5_parse_name(%s) failed (%s)\n",
1476                                     salt_principal, error_message(ret));
1477                         goto out;
1478                 }
1479
1480                 ret = smb_krb5_create_key_from_string(context,
1481                                                       salt_princ,
1482                                                       NULL,
1483                                                       password,
1484                                                       enctype,
1485                                                       keyp);
1486                 krb5_free_principal(context, salt_princ);
1487                 if (ret != 0) {
1488                         goto out;
1489                 }
1490         }
1491
1492         kt_entry.principal = princ;
1493         kt_entry.vno       = kvno;
1494
1495         DEBUG(3, (__location__ ": adding keytab entry for (%s) with "
1496                   "encryption type (%d) and version (%d)\n",
1497                   princ_s, enctype, kt_entry.vno));
1498         ret = krb5_kt_add_entry(context, keytab, &kt_entry);
1499         krb5_free_keyblock_contents(context, keyp);
1500         ZERO_STRUCT(kt_entry);
1501         if (ret) {
1502                 DEBUG(1, (__location__ ": adding entry to keytab "
1503                           "failed (%s)\n", error_message(ret)));
1504                 goto out;
1505         }
1506
1507 out:
1508         if (princ) {
1509                 krb5_free_principal(context, princ);
1510         }
1511
1512         return ret;
1513 }
1514
1515 #if defined(HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE) && \
1516     defined(HAVE_KRB5_GET_CREDS_OPT_ALLOC) && \
1517     defined(HAVE_KRB5_GET_CREDS)
1518 static krb5_error_code smb_krb5_get_credentials_for_user_opt(krb5_context context,
1519                                                              krb5_ccache ccache,
1520                                                              krb5_principal me,
1521                                                              krb5_principal server,
1522                                                              krb5_principal impersonate_princ,
1523                                                              krb5_creds **out_creds)
1524 {
1525         krb5_error_code ret;
1526         krb5_get_creds_opt opt;
1527
1528         ret = krb5_get_creds_opt_alloc(context, &opt);
1529         if (ret) {
1530                 goto done;
1531         }
1532         krb5_get_creds_opt_add_options(context, opt, KRB5_GC_FORWARDABLE);
1533
1534         if (impersonate_princ) {
1535                 ret = krb5_get_creds_opt_set_impersonate(context, opt,
1536                                                          impersonate_princ);
1537                 if (ret) {
1538                         goto done;
1539                 }
1540         }
1541
1542         ret = krb5_get_creds(context, opt, ccache, server, out_creds);
1543         if (ret) {
1544                 goto done;
1545         }
1546
1547  done:
1548         if (opt) {
1549                 krb5_get_creds_opt_free(context, opt);
1550         }
1551         return ret;
1552 }
1553 #endif /* HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE */
1554
1555 #ifdef HAVE_KRB5_GET_CREDENTIALS_FOR_USER
1556
1557 #if !HAVE_DECL_KRB5_GET_CREDENTIALS_FOR_USER
1558 krb5_error_code KRB5_CALLCONV
1559 krb5_get_credentials_for_user(krb5_context context, krb5_flags options,
1560                               krb5_ccache ccache, krb5_creds *in_creds,
1561                               krb5_data *subject_cert,
1562                               krb5_creds **out_creds);
1563 #endif /* !HAVE_DECL_KRB5_GET_CREDENTIALS_FOR_USER */
1564
1565 static krb5_error_code smb_krb5_get_credentials_for_user(krb5_context context,
1566                                                          krb5_ccache ccache,
1567                                                          krb5_principal me,
1568                                                          krb5_principal server,
1569                                                          krb5_principal impersonate_princ,
1570                                                          krb5_creds **out_creds)
1571 {
1572         krb5_error_code ret;
1573         krb5_creds in_creds;
1574
1575         ZERO_STRUCT(in_creds);
1576
1577         if (impersonate_princ) {
1578
1579                 in_creds.server = me;
1580                 in_creds.client = impersonate_princ;
1581
1582                 ret = krb5_get_credentials_for_user(context,
1583                                                     0, /* krb5_flags options */
1584                                                     ccache,
1585                                                     &in_creds,
1586                                                     NULL, /* krb5_data *subject_cert */
1587                                                     out_creds);
1588         } else {
1589                 in_creds.client = me;
1590                 in_creds.server = server;
1591
1592                 ret = krb5_get_credentials(context, 0, ccache,
1593                                            &in_creds, out_creds);
1594         }
1595
1596         return ret;
1597 }
1598 #endif /* HAVE_KRB5_GET_CREDENTIALS_FOR_USER */
1599
1600 /*
1601  * smb_krb5_get_credentials
1602  *
1603  * @brief Get krb5 credentials for a server
1604  *
1605  * @param[in] context           An initialized krb5_context
1606  * @param[in] ccache            An initialized krb5_ccache
1607  * @param[in] me                The krb5_principal of the caller
1608  * @param[in] server            The krb5_principal of the requested service
1609  * @param[in] impersonate_princ The krb5_principal of a user to impersonate as (optional)
1610  * @param[out] out_creds        The returned krb5_creds structure
1611  * @return krb5_error_code
1612  *
1613  */
1614 krb5_error_code smb_krb5_get_credentials(krb5_context context,
1615                                          krb5_ccache ccache,
1616                                          krb5_principal me,
1617                                          krb5_principal server,
1618                                          krb5_principal impersonate_princ,
1619                                          krb5_creds **out_creds)
1620 {
1621         krb5_error_code ret;
1622         krb5_creds *creds = NULL;
1623
1624         if (out_creds != NULL) {
1625                 *out_creds = NULL;
1626         }
1627
1628         if (impersonate_princ) {
1629 #ifdef HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE /* Heimdal */
1630                 ret = smb_krb5_get_credentials_for_user_opt(context, ccache, me, server, impersonate_princ, &creds);
1631 #elif defined(HAVE_KRB5_GET_CREDENTIALS_FOR_USER) /* MIT */
1632                 ret = smb_krb5_get_credentials_for_user(context, ccache, me, server, impersonate_princ, &creds);
1633 #else
1634                 ret = ENOTSUP;
1635 #endif
1636         } else {
1637                 krb5_creds in_creds;
1638
1639                 ZERO_STRUCT(in_creds);
1640
1641                 in_creds.client = me;
1642                 in_creds.server = server;
1643
1644                 ret = krb5_get_credentials(context, 0, ccache,
1645                                            &in_creds, &creds);
1646         }
1647         if (ret) {
1648                 goto done;
1649         }
1650
1651         if (out_creds) {
1652                 *out_creds = creds;
1653         }
1654
1655  done:
1656         if (creds && ret) {
1657                 krb5_free_creds(context, creds);
1658         }
1659
1660         return ret;
1661 }
1662
1663 /**
1664  * @brief Initialize a krb5_keyblock with the given data.
1665  *
1666  * Initialized a new keyblock, allocates the contents fo the key and
1667  * copies the data into the keyblock.
1668  *
1669  * @param[in]  context  The library context
1670  *
1671  * @param[in]  enctype  The encryption type.
1672  *
1673  * @param[in]  data     The date to initialize the keyblock with.
1674  *
1675  * @param[in]  length   The length of the keyblock.
1676  *
1677  * @param[in]  key      Newly allocated keyblock structure.
1678  *
1679  * The key date must be freed using krb5_free_keyblock_contents() when it is
1680  * no longer needed.
1681  *
1682  * @return 0 on success, a Kerberos error code otherwise.
1683  */
1684 krb5_error_code smb_krb5_keyblock_init_contents(krb5_context context,
1685                                                 krb5_enctype enctype,
1686                                                 const void *data,
1687                                                 size_t length,
1688                                                 krb5_keyblock *key)
1689 {
1690 #if defined(HAVE_KRB5_KEYBLOCK_INIT)
1691         return krb5_keyblock_init(context, enctype, data, length, key);
1692 #else
1693         memset(key, 0, sizeof(krb5_keyblock));
1694         KRB5_KEY_DATA(key) = SMB_MALLOC(length);
1695         if (NULL == KRB5_KEY_DATA(key)) {
1696                 return ENOMEM;
1697         }
1698         memcpy(KRB5_KEY_DATA(key), data, length);
1699         KRB5_KEY_LENGTH(key) = length;
1700         KRB5_KEY_TYPE(key) = enctype;
1701         return 0;
1702 #endif
1703 }
1704
1705 /**
1706  * @brief Simulate a kinit by putting the tgt in the given credential cache.
1707  *
1708  * This function uses a keyblock rather than needingthe original password.
1709  *
1710  * @param[in]  ctx      The library context
1711  *
1712  * @param[in]  cc       The credential cache to put the tgt in.
1713  *
1714  * @param[in]  principal The client princial
1715  *
1716  * @param[in]  keyblock  The keyblock to use.
1717  *
1718  * @param[in]  target_service The service name of the initial credentials (or NULL).
1719  *
1720  * @param[in]  krb_options Initial credential options.
1721  *
1722  * @param[in]  expire_time    A pointer to store the experation time of the
1723  *                            credentials (or NULL).
1724  *
1725  * @param[in]  kdc_time       A pointer to store the time when the ticket becomes
1726  *                            valid (or NULL).
1727  *
1728  * @return 0 on success, a Kerberos error code otherwise.
1729  */
1730 krb5_error_code smb_krb5_kinit_keyblock_ccache(krb5_context ctx,
1731                                                krb5_ccache cc,
1732                                                krb5_principal principal,
1733                                                krb5_keyblock *keyblock,
1734                                                const char *target_service,
1735                                                krb5_get_init_creds_opt *krb_options,
1736                                                time_t *expire_time,
1737                                                time_t *kdc_time)
1738 {
1739         krb5_error_code code = 0;
1740         krb5_creds my_creds;
1741
1742 #if defined(HAVE_KRB5_GET_INIT_CREDS_KEYBLOCK)
1743         code = krb5_get_init_creds_keyblock(ctx, &my_creds, principal,
1744                                             keyblock, 0, target_service,
1745                                             krb_options);
1746 #elif defined(HAVE_KRB5_GET_INIT_CREDS_KEYTAB)
1747 {
1748 #define SMB_CREDS_KEYTAB "MEMORY:tmp_smb_creds_XXXXXX"
1749         char tmp_name[sizeof(SMB_CREDS_KEYTAB)];
1750         krb5_keytab_entry entry;
1751         krb5_keytab keytab;
1752         mode_t mask;
1753
1754         memset(&entry, 0, sizeof(entry));
1755         entry.principal = principal;
1756         *(KRB5_KT_KEY(&entry)) = *keyblock;
1757
1758         memcpy(tmp_name, SMB_CREDS_KEYTAB, sizeof(SMB_CREDS_KEYTAB));
1759         mask = umask(S_IRWXO | S_IRWXG);
1760         mktemp(tmp_name);
1761         umask(mask);
1762         if (tmp_name[0] == 0) {
1763                 return KRB5_KT_BADNAME;
1764         }
1765         code = krb5_kt_resolve(ctx, tmp_name, &keytab);
1766         if (code) {
1767                 return code;
1768         }
1769
1770         code = krb5_kt_add_entry(ctx, keytab, &entry);
1771         if (code) {
1772                 (void)krb5_kt_close(ctx, keytab);
1773                 goto done;
1774         }
1775
1776         code = krb5_get_init_creds_keytab(ctx, &my_creds, principal,
1777                                           keytab, 0, target_service,
1778                                           krb_options);
1779         (void)krb5_kt_close(ctx, keytab);
1780 }
1781 #else
1782 #error krb5_get_init_creds_keyblock not available!
1783 #endif
1784         if (code) {
1785                 return code;
1786         }
1787
1788 #ifndef SAMBA4_USES_HEIMDAL /* MIT */
1789         /*
1790          * We need to store the principal as returned from the KDC to the
1791          * credentials cache. If we don't do that the KRB5 library is not
1792          * able to find the tickets it is looking for
1793          */
1794         principal = my_creds.client;
1795 #endif
1796         code = krb5_cc_initialize(ctx, cc, principal);
1797         if (code) {
1798                 goto done;
1799         }
1800
1801         code = krb5_cc_store_cred(ctx, cc, &my_creds);
1802         if (code) {
1803                 goto done;
1804         }
1805
1806         if (expire_time) {
1807                 *expire_time = (time_t) my_creds.times.endtime;
1808         }
1809
1810         if (kdc_time) {
1811                 *kdc_time = (time_t) my_creds.times.starttime;
1812         }
1813
1814         code = 0;
1815 done:
1816         krb5_free_cred_contents(ctx, &my_creds);
1817         return code;
1818 }
1819
1820 /**
1821  * @brief Simulate a kinit by putting the tgt in the given credential cache.
1822  *
1823  * @param[in]  ctx      The library context
1824  *
1825  * @param[in]  cc       The credential cache to put the tgt in.
1826  *
1827  * @param[in]  principal The client princial
1828  *
1829  * @param[in]  password  The password (or NULL).
1830  *
1831  * @param[in]  target_service The service name of the initial credentials (or NULL).
1832  *
1833  * @param[in]  krb_options Initial credential options.
1834  *
1835  * @param[in]  expire_time    A pointer to store the experation time of the
1836  *                            credentials (or NULL).
1837  *
1838  * @param[in]  kdc_time       A pointer to store the time when the ticket becomes
1839  *                            valid (or NULL).
1840  *
1841  * @return 0 on success, a Kerberos error code otherwise.
1842  */
1843 krb5_error_code smb_krb5_kinit_password_ccache(krb5_context ctx,
1844                                                krb5_ccache cc,
1845                                                krb5_principal principal,
1846                                                const char *password,
1847                                                const char *target_service,
1848                                                krb5_get_init_creds_opt *krb_options,
1849                                                time_t *expire_time,
1850                                                time_t *kdc_time)
1851 {
1852         krb5_error_code code = 0;
1853         krb5_creds my_creds;
1854
1855         code = krb5_get_init_creds_password(ctx, &my_creds, principal,
1856                                             password, NULL, NULL, 0,
1857                                             target_service, krb_options);
1858         if (code) {
1859                 return code;
1860         }
1861
1862 #ifndef SAMBA4_USES_HEIMDAL /* MIT */
1863         /*
1864          * We need to store the principal as returned from the KDC to the
1865          * credentials cache. If we don't do that the KRB5 library is not
1866          * able to find the tickets it is looking for
1867          */
1868         principal = my_creds.client;
1869 #endif
1870         code = krb5_cc_initialize(ctx, cc, principal);
1871         if (code) {
1872                 goto done;
1873         }
1874
1875         code = krb5_cc_store_cred(ctx, cc, &my_creds);
1876         if (code) {
1877                 goto done;
1878         }
1879
1880         if (expire_time) {
1881                 *expire_time = (time_t) my_creds.times.endtime;
1882         }
1883
1884         if (kdc_time) {
1885                 *kdc_time = (time_t) my_creds.times.starttime;
1886         }
1887
1888         code = 0;
1889 done:
1890         krb5_free_cred_contents(ctx, &my_creds);
1891         return code;
1892 }
1893
1894 #ifdef SAMBA4_USES_HEIMDAL
1895 /**
1896  * @brief Simulate a kinit by putting the tgt in the given credential cache.
1897  *
1898  * @param[in]  ctx      The library context
1899  *
1900  * @param[in]  cc       The credential cache to store the tgt in.
1901  *
1902  * @param[in]  principal The initial client princial.
1903  *
1904  * @param[in]  password  The password (or NULL).
1905  *
1906  * @param[in]  impersonate_principal The impersonatiion principal (or NULL).
1907  *
1908  * @param[in]  self_service The local service for S4U2Self if
1909  *                          impersonate_principal is specified).
1910  *
1911  * @param[in]  target_service The service name of the initial credentials
1912  *                            (kpasswd/REALM or a remote service). It defaults
1913  *                            to the krbtgt if NULL.
1914  *
1915  * @param[in]  krb_options Initial credential options.
1916  *
1917  * @param[in]  expire_time    A pointer to store the experation time of the
1918  *                            credentials (or NULL).
1919  *
1920  * @param[in]  kdc_time       A pointer to store the time when the ticket becomes
1921  *                            valid (or NULL).
1922  *
1923  * @return 0 on success, a Kerberos error code otherwise.
1924  */
1925 krb5_error_code smb_krb5_kinit_s4u2_ccache(krb5_context ctx,
1926                                            krb5_ccache store_cc,
1927                                            krb5_principal init_principal,
1928                                            const char *init_password,
1929                                            krb5_principal impersonate_principal,
1930                                            const char *self_service,
1931                                            const char *target_service,
1932                                            krb5_get_init_creds_opt *krb_options,
1933                                            time_t *expire_time,
1934                                            time_t *kdc_time)
1935 {
1936         krb5_error_code code = 0;
1937         krb5_get_creds_opt options;
1938         krb5_principal store_principal;
1939         krb5_creds store_creds;
1940         krb5_creds *s4u2self_creds;
1941         Ticket s4u2self_ticket;
1942         size_t s4u2self_ticketlen;
1943         krb5_creds *s4u2proxy_creds;
1944         krb5_principal self_princ;
1945         bool s4u2proxy;
1946         krb5_principal target_princ;
1947         krb5_ccache tmp_cc;
1948         const char *self_realm;
1949         krb5_principal blacklist_principal = NULL;
1950         krb5_principal whitelist_principal = NULL;
1951
1952         code = krb5_get_init_creds_password(ctx, &store_creds,
1953                                             init_principal,
1954                                             init_password,
1955                                             NULL, NULL,
1956                                             0,
1957                                             NULL,
1958                                             krb_options);
1959         if (code != 0) {
1960                 return code;
1961         }
1962
1963         store_principal = init_principal;
1964
1965         /*
1966          * We are trying S4U2Self now:
1967          *
1968          * As we do not want to expose our TGT in the
1969          * krb5_ccache, which is also holds the impersonated creds.
1970          *
1971          * Some low level krb5/gssapi function might use the TGT
1972          * identity and let the client act as our machine account.
1973          *
1974          * We need to avoid that and use a temporary krb5_ccache
1975          * in order to pass our TGT to the krb5_get_creds() function.
1976          */
1977         code = krb5_cc_new_unique(ctx, NULL, NULL, &tmp_cc);
1978         if (code != 0) {
1979                 krb5_free_cred_contents(ctx, &store_creds);
1980                 return code;
1981         }
1982
1983         code = krb5_cc_initialize(ctx, tmp_cc, store_creds.client);
1984         if (code != 0) {
1985                 krb5_cc_destroy(ctx, tmp_cc);
1986                 krb5_free_cred_contents(ctx, &store_creds);
1987                 return code;
1988         }
1989
1990         code = krb5_cc_store_cred(ctx, tmp_cc, &store_creds);
1991         if (code != 0) {
1992                 krb5_free_cred_contents(ctx, &store_creds);
1993                 krb5_cc_destroy(ctx, tmp_cc);
1994                 return code;
1995         }
1996
1997         /*
1998          * we need to remember the client principal of our
1999          * TGT and make sure the KDC does not return this
2000          * in the impersonated tickets. This can happen
2001          * if the KDC does not support S4U2Self and S4U2Proxy.
2002          */
2003         blacklist_principal = store_creds.client;
2004         store_creds.client = NULL;
2005         krb5_free_cred_contents(ctx, &store_creds);
2006
2007         /*
2008          * Check if we also need S4U2Proxy or if S4U2Self is
2009          * enough in order to get a ticket for the target.
2010          */
2011         if (target_service == NULL) {
2012                 s4u2proxy = false;
2013         } else if (strcmp(target_service, self_service) == 0) {
2014                 s4u2proxy = false;
2015         } else {
2016                 s4u2proxy = true;
2017         }
2018
2019         /*
2020          * For S4U2Self we need our own service principal,
2021          * which belongs to our own realm (available on
2022          * our client principal).
2023          */
2024         self_realm = krb5_principal_get_realm(ctx, init_principal);
2025
2026         code = krb5_parse_name(ctx, self_service, &self_princ);
2027         if (code != 0) {
2028                 krb5_free_principal(ctx, blacklist_principal);
2029                 krb5_cc_destroy(ctx, tmp_cc);
2030                 return code;
2031         }
2032
2033         code = krb5_principal_set_realm(ctx, self_princ, self_realm);
2034         if (code != 0) {
2035                 krb5_free_principal(ctx, blacklist_principal);
2036                 krb5_free_principal(ctx, self_princ);
2037                 krb5_cc_destroy(ctx, tmp_cc);
2038                 return code;
2039         }
2040
2041         code = krb5_get_creds_opt_alloc(ctx, &options);
2042         if (code != 0) {
2043                 krb5_free_principal(ctx, blacklist_principal);
2044                 krb5_free_principal(ctx, self_princ);
2045                 krb5_cc_destroy(ctx, tmp_cc);
2046                 return code;
2047         }
2048
2049         if (s4u2proxy) {
2050                 /*
2051                  * If we want S4U2Proxy, we need the forwardable flag
2052                  * on the S4U2Self ticket.
2053                  */
2054                 krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_FORWARDABLE);
2055         }
2056
2057         code = krb5_get_creds_opt_set_impersonate(ctx, options,
2058                                                   impersonate_principal);
2059         if (code != 0) {
2060                 krb5_get_creds_opt_free(ctx, options);
2061                 krb5_free_principal(ctx, blacklist_principal);
2062                 krb5_free_principal(ctx, self_princ);
2063                 krb5_cc_destroy(ctx, tmp_cc);
2064                 return code;
2065         }
2066
2067         code = krb5_get_creds(ctx, options, tmp_cc,
2068                               self_princ, &s4u2self_creds);
2069         krb5_get_creds_opt_free(ctx, options);
2070         krb5_free_principal(ctx, self_princ);
2071         if (code != 0) {
2072                 krb5_free_principal(ctx, blacklist_principal);
2073                 krb5_cc_destroy(ctx, tmp_cc);
2074                 return code;
2075         }
2076
2077         if (!s4u2proxy) {
2078                 krb5_cc_destroy(ctx, tmp_cc);
2079
2080                 /*
2081                  * Now make sure we store the impersonated principal
2082                  * and creds instead of the TGT related stuff
2083                  * in the krb5_ccache of the caller.
2084                  */
2085                 code = krb5_copy_creds_contents(ctx, s4u2self_creds,
2086                                                 &store_creds);
2087                 krb5_free_creds(ctx, s4u2self_creds);
2088                 if (code != 0) {
2089                         return code;
2090                 }
2091
2092                 /*
2093                  * It's important to store the principal the KDC
2094                  * returned, as otherwise the caller would not find
2095                  * the S4U2Self ticket in the krb5_ccache lookup.
2096                  */
2097                 store_principal = store_creds.client;
2098                 goto store;
2099         }
2100
2101         /*
2102          * We are trying S4U2Proxy:
2103          *
2104          * We need the ticket from the S4U2Self step
2105          * and our TGT in order to get the delegated ticket.
2106          */
2107         code = decode_Ticket((const uint8_t *)s4u2self_creds->ticket.data,
2108                              s4u2self_creds->ticket.length,
2109                              &s4u2self_ticket,
2110                              &s4u2self_ticketlen);
2111         if (code != 0) {
2112                 krb5_free_creds(ctx, s4u2self_creds);
2113                 krb5_free_principal(ctx, blacklist_principal);
2114                 krb5_cc_destroy(ctx, tmp_cc);
2115                 return code;
2116         }
2117
2118         /*
2119          * we need to remember the client principal of the
2120          * S4U2Self stage and as it needs to match the one we
2121          * will get for the S4U2Proxy stage. We need this
2122          * in order to detect KDCs which does not support S4U2Proxy.
2123          */
2124         whitelist_principal = s4u2self_creds->client;
2125         s4u2self_creds->client = NULL;
2126         krb5_free_creds(ctx, s4u2self_creds);
2127
2128         /*
2129          * For S4U2Proxy we also got a target service principal,
2130          * which also belongs to our own realm (available on
2131          * our client principal).
2132          */
2133         code = krb5_parse_name(ctx, target_service, &target_princ);
2134         if (code != 0) {
2135                 free_Ticket(&s4u2self_ticket);
2136                 krb5_free_principal(ctx, whitelist_principal);
2137                 krb5_free_principal(ctx, blacklist_principal);
2138                 krb5_cc_destroy(ctx, tmp_cc);
2139                 return code;
2140         }
2141
2142         code = krb5_principal_set_realm(ctx, target_princ, self_realm);
2143         if (code != 0) {
2144                 free_Ticket(&s4u2self_ticket);
2145                 krb5_free_principal(ctx, target_princ);
2146                 krb5_free_principal(ctx, whitelist_principal);
2147                 krb5_free_principal(ctx, blacklist_principal);
2148                 krb5_cc_destroy(ctx, tmp_cc);
2149                 return code;
2150         }
2151
2152         code = krb5_get_creds_opt_alloc(ctx, &options);
2153         if (code != 0) {
2154                 free_Ticket(&s4u2self_ticket);
2155                 krb5_free_principal(ctx, target_princ);
2156                 krb5_free_principal(ctx, whitelist_principal);
2157                 krb5_free_principal(ctx, blacklist_principal);
2158                 krb5_cc_destroy(ctx, tmp_cc);
2159                 return code;
2160         }
2161
2162         krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_FORWARDABLE);
2163         krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_CONSTRAINED_DELEGATION);
2164
2165         code = krb5_get_creds_opt_set_ticket(ctx, options, &s4u2self_ticket);
2166         free_Ticket(&s4u2self_ticket);
2167         if (code != 0) {
2168                 krb5_get_creds_opt_free(ctx, options);
2169                 krb5_free_principal(ctx, target_princ);
2170                 krb5_free_principal(ctx, whitelist_principal);
2171                 krb5_free_principal(ctx, blacklist_principal);
2172                 krb5_cc_destroy(ctx, tmp_cc);
2173                 return code;
2174         }
2175
2176         code = krb5_get_creds(ctx, options, tmp_cc,
2177                               target_princ, &s4u2proxy_creds);
2178         krb5_get_creds_opt_free(ctx, options);
2179         krb5_free_principal(ctx, target_princ);
2180         krb5_cc_destroy(ctx, tmp_cc);
2181         if (code != 0) {
2182                 krb5_free_principal(ctx, whitelist_principal);
2183                 krb5_free_principal(ctx, blacklist_principal);
2184                 return code;
2185         }
2186
2187         /*
2188          * Now make sure we store the impersonated principal
2189          * and creds instead of the TGT related stuff
2190          * in the krb5_ccache of the caller.
2191          */
2192         code = krb5_copy_creds_contents(ctx, s4u2proxy_creds,
2193                                         &store_creds);
2194         krb5_free_creds(ctx, s4u2proxy_creds);
2195         if (code != 0) {
2196                 krb5_free_principal(ctx, whitelist_principal);
2197                 krb5_free_principal(ctx, blacklist_principal);
2198                 return code;
2199         }
2200
2201         /*
2202          * It's important to store the principal the KDC
2203          * returned, as otherwise the caller would not find
2204          * the S4U2Self ticket in the krb5_ccache lookup.
2205          */
2206         store_principal = store_creds.client;
2207
2208  store:
2209         if (blacklist_principal &&
2210             krb5_principal_compare(ctx, store_creds.client, blacklist_principal)) {
2211                 char *sp = NULL;
2212                 char *ip = NULL;
2213
2214                 code = krb5_unparse_name(ctx, blacklist_principal, &sp);
2215                 if (code != 0) {
2216                         sp = NULL;
2217                 }
2218                 code = krb5_unparse_name(ctx, impersonate_principal, &ip);
2219                 if (code != 0) {
2220                         ip = NULL;
2221                 }
2222                 DEBUG(1, ("smb_krb5_kinit_password_cache: "
2223                           "KDC returned self principal[%s] while impersonating [%s]\n",
2224                           sp?sp:"<no memory>",
2225                           ip?ip:"<no memory>"));
2226
2227                 SAFE_FREE(sp);
2228                 SAFE_FREE(ip);
2229
2230                 krb5_free_principal(ctx, whitelist_principal);
2231                 krb5_free_principal(ctx, blacklist_principal);
2232                 krb5_free_cred_contents(ctx, &store_creds);
2233                 return KRB5_FWD_BAD_PRINCIPAL;
2234         }
2235         if (blacklist_principal) {
2236                 krb5_free_principal(ctx, blacklist_principal);
2237         }
2238
2239         if (whitelist_principal &&
2240             !krb5_principal_compare(ctx, store_creds.client, whitelist_principal)) {
2241                 char *sp = NULL;
2242                 char *ep = NULL;
2243
2244                 code = krb5_unparse_name(ctx, store_creds.client, &sp);
2245                 if (code != 0) {
2246                         sp = NULL;
2247                 }
2248                 code = krb5_unparse_name(ctx, whitelist_principal, &ep);
2249                 if (code != 0) {
2250                         ep = NULL;
2251                 }
2252                 DEBUG(1, ("smb_krb5_kinit_password_cache: "
2253                           "KDC returned wrong principal[%s] we expected [%s]\n",
2254                           sp?sp:"<no memory>",
2255                           ep?ep:"<no memory>"));
2256
2257                 SAFE_FREE(sp);
2258                 SAFE_FREE(ep);
2259
2260                 krb5_free_principal(ctx, whitelist_principal);
2261                 krb5_free_cred_contents(ctx, &store_creds);
2262                 return KRB5_FWD_BAD_PRINCIPAL;
2263         }
2264         if (whitelist_principal) {
2265                 krb5_free_principal(ctx, whitelist_principal);
2266         }
2267
2268         code = krb5_cc_initialize(ctx, store_cc, store_principal);
2269         if (code != 0) {
2270                 krb5_free_cred_contents(ctx, &store_creds);
2271                 return code;
2272         }
2273
2274         code = krb5_cc_store_cred(ctx, store_cc, &store_creds);
2275         if (code != 0) {
2276                 krb5_free_cred_contents(ctx, &store_creds);
2277                 return code;
2278         }
2279
2280         if (expire_time) {
2281                 *expire_time = (time_t) store_creds.times.endtime;
2282         }
2283
2284         if (kdc_time) {
2285                 *kdc_time = (time_t) store_creds.times.starttime;
2286         }
2287
2288         krb5_free_cred_contents(ctx, &store_creds);
2289
2290         return 0;
2291 }
2292 #endif
2293
2294 #if !defined(HAVE_KRB5_MAKE_PRINCIPAL) && defined(HAVE_KRB5_BUILD_PRINCIPAL_ALLOC_VA)
2295 /**
2296  * @brief Create a principal name using a variable argument list.
2297  *
2298  * @param[in]  context  The library context.
2299  *
2300  * @param[inout]  principal A pointer to the principal structure.
2301  *
2302  * @param[in]  _realm    The realm to use. If NULL then the function will
2303  *                       get the default realm name.
2304  *
2305  * @param[in]  ...       A list of 'char *' components, ending with NULL.
2306  *
2307  * Use krb5_free_principal() to free the principal when it is no longer needed.
2308  *
2309  * @return 0 on success, a Kerberos error code otherwise.
2310  */
2311 krb5_error_code smb_krb5_make_principal(krb5_context context,
2312                                         krb5_principal *principal,
2313                                         const char *_realm, ...)
2314 {
2315         krb5_error_code code;
2316         bool free_realm;
2317         char *realm;
2318         va_list ap;
2319
2320         if (_realm) {
2321                 realm = discard_const_p(char, _realm);
2322                 free_realm = false;
2323         } else {
2324                 code = krb5_get_default_realm(context, &realm);
2325                 if (code) {
2326                         return code;
2327                 }
2328                 free_realm = true;
2329         }
2330
2331         va_start(ap, _realm);
2332         code = krb5_build_principal_alloc_va(context, principal,
2333                                              strlen(realm), realm,
2334                                              ap);
2335         va_end(ap);
2336
2337         if (free_realm) {
2338                 krb5_free_default_realm(context, realm);
2339         }
2340
2341         return code;
2342 }
2343 #endif
2344
2345 #if !defined(HAVE_KRB5_CC_GET_LIFETIME) && defined(HAVE_KRB5_CC_RETRIEVE_CRED)
2346 /**
2347  * @brief Get the lifetime of the initial ticket in the cache.
2348  *
2349  * @param[in]  context  The kerberos context.
2350  *
2351  * @param[in]  id       The credential cache to get the ticket lifetime.
2352  *
2353  * @param[out] t        A pointer to a time value to store the lifetime.
2354  *
2355  * @return              0 on success, a krb5_error_code on error.
2356  */
2357 krb5_error_code smb_krb5_cc_get_lifetime(krb5_context context,
2358                                          krb5_ccache id,
2359                                          time_t *t)
2360 {
2361         krb5_cc_cursor cursor;
2362         krb5_error_code kerr;
2363         krb5_creds cred;
2364         krb5_timestamp now;
2365
2366         *t = 0;
2367
2368         kerr = krb5_timeofday(context, &now);
2369         if (kerr) {
2370                 return kerr;
2371         }
2372
2373         kerr = krb5_cc_start_seq_get(context, id, &cursor);
2374         if (kerr) {
2375                 return kerr;
2376         }
2377
2378         while ((kerr = krb5_cc_next_cred(context, id, &cursor, &cred)) == 0) {
2379 #ifndef HAVE_FLAGS_IN_KRB5_CREDS
2380                 if (cred.ticket_flags & TKT_FLG_INITIAL) {
2381 #else
2382                 if (cred.flags.b.initial) {
2383 #endif
2384                         if (now < cred.times.endtime) {
2385                                 *t = (time_t) (cred.times.endtime - now);
2386                         }
2387                         krb5_free_cred_contents(context, &cred);
2388                         break;
2389                 }
2390                 krb5_free_cred_contents(context, &cred);
2391         }
2392
2393         krb5_cc_end_seq_get(context, id, &cursor);
2394
2395         return kerr;
2396 }
2397 #endif /* HAVE_KRB5_CC_GET_LIFETIME */
2398
2399 #if !defined(HAVE_KRB5_FREE_CHECKSUM_CONTENTS) && defined(HAVE_FREE_CHECKSUM)
2400 void smb_krb5_free_checksum_contents(krb5_context ctx, krb5_checksum *cksum)
2401 {
2402         free_Checksum(cksum);
2403 }
2404 #endif
2405
2406 /**
2407  * @brief Compute a checksum operating on a keyblock.
2408  *
2409  * This function computes a checksum over a PAC using the keyblock for a keyed
2410  * checksum.
2411  *
2412  * @param[in]  mem_ctx A talloc context to alocate the signature on.
2413  *
2414  * @param[in]  pac_data The PAC as input.
2415  *
2416  * @param[in]  context  The library context.
2417  *
2418  * @param[in]  keyblock Encryption key for a keyed checksum.
2419  *
2420  * @param[out] sig_type The checksum type
2421  *
2422  * @param[out] sig_blob The talloc'ed checksum
2423  *
2424  * The caller must free the sig_blob with talloc_free() when it is not needed
2425  * anymore.
2426  *
2427  * @return 0 on success, a Kerberos error code otherwise.
2428  */
2429 krb5_error_code smb_krb5_make_pac_checksum(TALLOC_CTX *mem_ctx,
2430                                            DATA_BLOB *pac_data,
2431                                            krb5_context context,
2432                                            const krb5_keyblock *keyblock,
2433                                            uint32_t *sig_type,
2434                                            DATA_BLOB *sig_blob)
2435 {
2436         krb5_error_code ret;
2437         krb5_checksum cksum;
2438 #if defined(HAVE_KRB5_CRYPTO_INIT) && defined(HAVE_KRB5_CREATE_CHECKSUM)
2439         krb5_crypto crypto;
2440
2441
2442         ret = krb5_crypto_init(context,
2443                                keyblock,
2444                                0,
2445                                &crypto);
2446         if (ret) {
2447                 DEBUG(0,("krb5_crypto_init() failed: %s\n",
2448                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2449                 return ret;
2450         }
2451         ret = krb5_create_checksum(context,
2452                                    crypto,
2453                                    KRB5_KU_OTHER_CKSUM,
2454                                    0,
2455                                    pac_data->data,
2456                                    pac_data->length,
2457                                    &cksum);
2458         if (ret) {
2459                 DEBUG(2, ("PAC Verification failed: %s\n",
2460                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2461         }
2462
2463         krb5_crypto_destroy(context, crypto);
2464
2465         if (ret) {
2466                 return ret;
2467         }
2468
2469         *sig_type = cksum.cksumtype;
2470         *sig_blob = data_blob_talloc(mem_ctx,
2471                                         cksum.checksum.data,
2472                                         cksum.checksum.length);
2473 #elif defined(HAVE_KRB5_C_MAKE_CHECKSUM)
2474         krb5_data input;
2475
2476         input.data = (char *)pac_data->data;
2477         input.length = pac_data->length;
2478
2479         ret = krb5_c_make_checksum(context,
2480                                    0,
2481                                    keyblock,
2482                                    KRB5_KEYUSAGE_APP_DATA_CKSUM,
2483                                    &input,
2484                                    &cksum);
2485         if (ret) {
2486                 DEBUG(2, ("PAC Verification failed: %s\n",
2487                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2488                 return ret;
2489         }
2490
2491         *sig_type = cksum.checksum_type;
2492         *sig_blob = data_blob_talloc(mem_ctx,
2493                                         cksum.contents,
2494                                         cksum.length);
2495
2496 #else
2497 #error krb5_create_checksum or krb5_c_make_checksum not available
2498 #endif /* HAVE_KRB5_C_MAKE_CHECKSUM */
2499         smb_krb5_free_checksum_contents(context, &cksum);
2500
2501         return 0;
2502 }
2503
2504
2505 /**
2506  * @brief Get realm of a principal
2507  *
2508  * @param[in] context   The library context
2509  *
2510  * @param[in] principal The principal to get the realm from.
2511  *
2512  * @return An allocated string with the realm or NULL if an error occured.
2513  *
2514  * The caller must free the realm string with free() if not needed anymore.
2515  */
2516 char *smb_krb5_principal_get_realm(krb5_context context,
2517                                    krb5_const_principal principal)
2518 {
2519 #ifdef HAVE_KRB5_PRINCIPAL_GET_REALM /* Heimdal */
2520         return strdup(discard_const_p(char, krb5_principal_get_realm(context, principal)));
2521 #elif defined(krb5_princ_realm) /* MIT */
2522         krb5_data *realm;
2523         realm = discard_const_p(krb5_data,
2524                                 krb5_princ_realm(context, principal));
2525         return strndup(realm->data, realm->length);
2526 #else
2527 #error UNKNOWN_GET_PRINC_REALM_FUNCTIONS
2528 #endif
2529 }
2530
2531 /**
2532  * @brief Get realm of a principal
2533  *
2534  * @param[in] context   The library context
2535  *
2536  * @param[in] principal The principal to set the realm
2537  *
2538  * @param[in] realm     The realm as a string to set.
2539  *
2540  * @retur 0 on success, a Kerberos error code otherwise.
2541  */
2542 krb5_error_code smb_krb5_principal_set_realm(krb5_context context,
2543                                              krb5_principal principal,
2544                                              const char *realm)
2545 {
2546 #ifdef HAVE_KRB5_PRINCIPAL_SET_REALM /* Heimdal */
2547         return krb5_principal_set_realm(context, principal, realm);
2548 #elif defined(krb5_princ_realm) && defined(krb5_princ_set_realm) /* MIT */
2549         krb5_error_code ret;
2550         krb5_data data;
2551         krb5_data *old_data;
2552
2553         old_data = krb5_princ_realm(context, principal);
2554
2555         ret = smb_krb5_copy_data_contents(&data,
2556                                           realm,
2557                                           strlen(realm));
2558         if (ret) {
2559                 return ret;
2560         }
2561
2562         /* free realm before setting */
2563         free(old_data->data);
2564
2565         krb5_princ_set_realm(context, principal, &data);
2566
2567         return ret;
2568 #else
2569 #error UNKNOWN_PRINC_SET_REALM_FUNCTION
2570 #endif
2571 }
2572
2573
2574 /************************************************************************
2575  Routine to get the default realm from the kerberos credentials cache.
2576  Caller must free if the return value is not NULL.
2577 ************************************************************************/
2578
2579 static char *smb_krb5_get_default_realm_from_ccache(TALLOC_CTX *mem_ctx)
2580 {
2581         char *realm = NULL;
2582         krb5_context ctx = NULL;
2583         krb5_ccache cc = NULL;
2584         krb5_principal princ = NULL;
2585
2586         initialize_krb5_error_table();
2587         if (krb5_init_context(&ctx)) {
2588                 return NULL;
2589         }
2590
2591         DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2592                 "Trying to read krb5 cache: %s\n",
2593                 krb5_cc_default_name(ctx)));
2594         if (krb5_cc_default(ctx, &cc)) {
2595                 DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2596                         "failed to read default cache\n"));
2597                 goto out;
2598         }
2599         if (krb5_cc_get_principal(ctx, cc, &princ)) {
2600                 DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2601                         "failed to get default principal\n"));
2602                 goto out;
2603         }
2604
2605 #if defined(HAVE_KRB5_PRINCIPAL_GET_REALM)
2606         realm = talloc_strdup(mem_ctx, krb5_principal_get_realm(ctx, princ));
2607 #elif defined(HAVE_KRB5_PRINC_REALM)
2608         {
2609                 krb5_data *realm_data = krb5_princ_realm(ctx, princ);
2610                 realm = talloc_strndup(mem_ctx, realm_data->data, realm_data->length);
2611         }
2612 #endif
2613
2614   out:
2615
2616         if (ctx) {
2617                 if (princ) {
2618                         krb5_free_principal(ctx, princ);
2619                 }
2620                 if (cc) {
2621                         krb5_cc_close(ctx, cc);
2622                 }
2623                 krb5_free_context(ctx);
2624         }
2625
2626         return realm;
2627 }
2628
2629 /************************************************************************
2630  Routine to get the realm from a given DNS name.
2631 ************************************************************************/
2632
2633 static char *smb_krb5_get_realm_from_hostname(TALLOC_CTX *mem_ctx,
2634                                                 const char *hostname)
2635 {
2636 #if defined(HAVE_KRB5_REALM_TYPE)
2637         /* Heimdal. */
2638         krb5_realm *realm_list = NULL;
2639 #else
2640         /* MIT */
2641         char **realm_list = NULL;
2642 #endif
2643         char *realm = NULL;
2644         krb5_error_code kerr;
2645         krb5_context ctx = NULL;
2646
2647         initialize_krb5_error_table();
2648         if (krb5_init_context(&ctx)) {
2649                 return NULL;
2650         }
2651
2652         kerr = krb5_get_host_realm(ctx, hostname, &realm_list);
2653         if (kerr != 0) {
2654                 DEBUG(3,("kerberos_get_realm_from_hostname %s: "
2655                         "failed %s\n",
2656                         hostname ? hostname : "(NULL)",
2657                         error_message(kerr) ));
2658                 goto out;
2659         }
2660
2661         if (realm_list && realm_list[0]) {
2662                 realm = talloc_strdup(mem_ctx, realm_list[0]);
2663         }
2664
2665   out:
2666
2667         if (ctx) {
2668                 if (realm_list) {
2669                         krb5_free_host_realm(ctx, realm_list);
2670                         realm_list = NULL;
2671                 }
2672                 krb5_free_context(ctx);
2673                 ctx = NULL;
2674         }
2675         return realm;
2676 }
2677
2678 /**
2679  * @brief Get the principal as a string from the service hostname.
2680  *
2681  * @param[in]  mem_ctx  The talloc context
2682  *
2683  * @param[in]  service  The service name
2684  *
2685  * @param[in]  remote_name The remote name
2686  *
2687  * @param[in]  default_realm The default_realm if we cannot get it from the
2688  *                           hostname or netbios name.
2689  *
2690  * @return A talloc'ed principal string or NULL if an error occured.
2691  *
2692  * The caller needs to free the principal with talloc_free() if it isn't needed
2693  * anymore.
2694  */
2695 char *smb_krb5_get_principal_from_service_hostname(TALLOC_CTX *mem_ctx,
2696                                                    const char *service,
2697                                                    const char *remote_name,
2698                                                    const char *default_realm)
2699 {
2700         char *realm = NULL;
2701         char *host = NULL;
2702         char *principal;
2703         host = strchr_m(remote_name, '.');
2704         if (host) {
2705                 /* DNS name. */
2706                 realm = smb_krb5_get_realm_from_hostname(talloc_tos(),
2707                                                          remote_name);
2708         } else {
2709                 /* NetBIOS name - use our realm. */
2710                 realm = smb_krb5_get_default_realm_from_ccache(talloc_tos());
2711         }
2712
2713         if (realm == NULL || *realm == '\0') {
2714                 realm = talloc_strdup(talloc_tos(), default_realm);
2715                 if (!realm) {
2716                         return NULL;
2717                 }
2718                 DEBUG(3,("Cannot get realm from, "
2719                          "desthost %s or default ccache. Using default "
2720                          "smb.conf realm %s\n",
2721                          remote_name,
2722                          realm));
2723         }
2724
2725         principal = talloc_asprintf(mem_ctx,
2726                                     "%s/%s@%s",
2727                                     service, remote_name,
2728                                     realm);
2729         TALLOC_FREE(realm);
2730         return principal;
2731 }
2732
2733 /**
2734  * @brief Get an error string from a Kerberos error code.
2735  *
2736  * @param[in]  context  The library context.
2737  *
2738  * @param[in]  code     The Kerberos error code.
2739  *
2740  * @param[in]  mem_ctx  The talloc context to allocate the error string on.
2741  *
2742  * @return A talloc'ed error string or NULL if an error occured.
2743  *
2744  * The caller must free the returned error string with talloc_free() if not
2745  * needed anymore
2746  */
2747 char *smb_get_krb5_error_message(krb5_context context,
2748                                  krb5_error_code code,
2749                                  TALLOC_CTX *mem_ctx)
2750 {
2751         char *ret;
2752
2753 #if defined(HAVE_KRB5_GET_ERROR_MESSAGE) && defined(HAVE_KRB5_FREE_ERROR_MESSAGE)
2754         const char *context_error = krb5_get_error_message(context, code);
2755         if (context_error) {
2756                 ret = talloc_asprintf(mem_ctx, "%s: %s",
2757                                         error_message(code), context_error);
2758                 krb5_free_error_message(context, context_error);
2759                 return ret;
2760         }
2761 #endif
2762         ret = talloc_strdup(mem_ctx, error_message(code));
2763         return ret;
2764 }
2765
2766
2767 /**
2768  * @brief Return the kerberos library setting for: libdefaults:allow_weak_crypto
2769  *
2770  * @param[in]  context  The library context
2771  *
2772  * @return True if weak crypto is allowed, false if not.
2773  */
2774 krb5_boolean smb_krb5_get_allowed_weak_crypto(krb5_context context)
2775 #if defined(HAVE_KRB5_CONFIG_GET_BOOL_DEFAULT)
2776 {
2777         return krb5_config_get_bool_default(context,
2778                                             NULL,
2779                                             FALSE,
2780                                             "libdefaults",
2781                                             "allow_weak_crypto",
2782                                             NULL);
2783 }
2784 #elif defined(HAVE_PROFILE_H) && defined(HAVE_KRB5_GET_PROFILE)
2785 {
2786 #include <profile.h>
2787         krb5_error_code ret;
2788         krb5_boolean ret_default = false;
2789         profile_t profile;
2790         int ret_profile;
2791
2792         ret = krb5_get_profile(context,
2793                                &profile);
2794         if (ret) {
2795                 return ret_default;
2796         }
2797
2798         ret = profile_get_boolean(profile,
2799                                   "libdefaults",
2800                                   "allow_weak_crypto",
2801                                   NULL, /* subsubname */
2802                                   ret_default, /* def_val */
2803                                   &ret_profile /* *ret_default */);
2804         if (ret) {
2805                 return ret_default;
2806         }
2807
2808         profile_release(profile);
2809
2810         return ret_profile;
2811 }
2812 #else
2813 #error UNKNOWN_KRB5_CONFIG_ROUTINES
2814 #endif
2815
2816 /**
2817  * @brief Return the type of a krb5_principal
2818  *
2819  * @param[in]  context  The library context.
2820  *
2821  * @param[in]  principal The principal to get the type from.
2822  *
2823  * @return The integer type of the principal.
2824  */
2825 int smb_krb5_principal_get_type(krb5_context context,
2826                                 krb5_const_principal principal)
2827 {
2828 #ifdef HAVE_KRB5_PRINCIPAL_GET_TYPE /* Heimdal */
2829         return krb5_principal_get_type(context, principal);
2830 #elif defined(krb5_princ_type) /* MIT */
2831         return krb5_princ_type(context, principal);
2832 #else
2833 #error  UNKNOWN_PRINC_GET_TYPE_FUNCTION
2834 #endif
2835 }
2836
2837 /**
2838  * @brief Set the type of a principal
2839  *
2840  * @param[in]  context  The library context
2841  *
2842  * @param[inout] principal The principal to set the type for.
2843  *
2844  * @param[in]  type     The principal type to set.
2845  */
2846 void smb_krb5_principal_set_type(krb5_context context,
2847                                  krb5_principal principal,
2848                                  int type)
2849 {
2850 #ifdef HAVE_KRB5_PRINCIPAL_SET_TYPE /* Heimdal */
2851         krb5_principal_set_type(context, principal, type);
2852 #elif defined(krb5_princ_type) /* MIT */
2853         krb5_princ_type(context, principal) = type;
2854 #else
2855 #error  UNKNOWN_PRINC_SET_TYPE_FUNCTION
2856 #endif
2857 }
2858
2859 #if !defined(HAVE_KRB5_WARNX)
2860 /**
2861  * @brief Log a Kerberos message
2862  *
2863  * It sends the message to com_err.
2864  *
2865  * @param[in]  context  The library context
2866  *
2867  * @param[in]  fmt      The message format
2868  *
2869  * @param[in]  ...      The message arguments
2870  *
2871  * @return 0 on success.
2872  */
2873 krb5_error_code krb5_warnx(krb5_context context, const char *fmt, ...)
2874 {
2875         va_list args;
2876
2877         va_start(args, fmt);
2878         com_err_va("samba-kdc", errno, fmt, args);
2879         va_end(args);
2880
2881         return 0;
2882 }
2883 #endif
2884
2885 /**
2886  * @brief Copy a credential cache.
2887  *
2888  * @param[in]  context  The library context.
2889  *
2890  * @param[in]  incc     Credential cache to be copied.
2891  *
2892  * @param[inout] outcc  Copy of credential cache to be filled in.
2893  *
2894  * @return 0 on success, a Kerberos error code otherwise.
2895  */
2896 krb5_error_code smb_krb5_cc_copy_creds(krb5_context context,
2897                                        krb5_ccache incc, krb5_ccache outcc)
2898 {
2899 #ifdef HAVE_KRB5_CC_COPY_CACHE /* Heimdal */
2900         return krb5_cc_copy_cache(context, incc, outcc);
2901 #elif defined(HAVE_KRB5_CC_COPY_CREDS)
2902         krb5_error_code ret;
2903         krb5_principal princ = NULL;
2904
2905         ret = krb5_cc_get_principal(context, incc, &princ);
2906         if (ret != 0) {
2907                 return ret;
2908         }
2909         ret = krb5_cc_initialize(context, outcc, princ);
2910         krb5_free_principal(context, princ);
2911         if (ret != 0) {
2912                 return ret;
2913         }
2914         return krb5_cc_copy_creds(context, incc, outcc);
2915 #else
2916 #error UNKNOWN_KRB5_CC_COPY_CACHE_OR_CREDS_FUNCTION
2917 #endif
2918 }
2919
2920 /**********************************************************
2921  * ADS KRB5 CALLS
2922  **********************************************************/
2923
2924 static bool ads_cleanup_expired_creds(krb5_context context,
2925                                       krb5_ccache  ccache,
2926                                       krb5_creds  *credsp)
2927 {
2928         krb5_error_code retval;
2929         const char *cc_type = krb5_cc_get_type(context, ccache);
2930
2931         DEBUG(3, ("ads_cleanup_expired_creds: Ticket in ccache[%s:%s] expiration %s\n",
2932                   cc_type, krb5_cc_get_name(context, ccache),
2933                   http_timestring(talloc_tos(), credsp->times.endtime)));
2934
2935         /* we will probably need new tickets if the current ones
2936            will expire within 10 seconds.
2937         */
2938         if (credsp->times.endtime >= (time(NULL) + 10))
2939                 return false;
2940
2941         /* heimdal won't remove creds from a file ccache, and
2942            perhaps we shouldn't anyway, since internally we
2943            use memory ccaches, and a FILE one probably means that
2944            we're using creds obtained outside of our exectuable
2945         */
2946         if (strequal(cc_type, "FILE")) {
2947                 DEBUG(5, ("ads_cleanup_expired_creds: We do not remove creds from a %s ccache\n", cc_type));
2948                 return false;
2949         }
2950
2951         retval = krb5_cc_remove_cred(context, ccache, 0, credsp);
2952         if (retval) {
2953                 DEBUG(1, ("ads_cleanup_expired_creds: krb5_cc_remove_cred failed, err %s\n",
2954                           error_message(retval)));
2955                 /* If we have an error in this, we want to display it,
2956                    but continue as though we deleted it */
2957         }
2958         return true;
2959 }
2960
2961 /* Allocate and setup the auth context into the state we need. */
2962
2963 static krb5_error_code ads_setup_auth_context(krb5_context context,
2964                                               krb5_auth_context *auth_context)
2965 {
2966         krb5_error_code retval;
2967
2968         retval = krb5_auth_con_init(context, auth_context );
2969         if (retval) {
2970                 DEBUG(1,("krb5_auth_con_init failed (%s)\n",
2971                         error_message(retval)));
2972                 return retval;
2973         }
2974
2975         /* Ensure this is an addressless ticket. */
2976         retval = krb5_auth_con_setaddrs(context, *auth_context, NULL, NULL);
2977         if (retval) {
2978                 DEBUG(1,("krb5_auth_con_setaddrs failed (%s)\n",
2979                         error_message(retval)));
2980         }
2981
2982         return retval;
2983 }
2984
2985 #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE)
2986 static krb5_error_code ads_create_gss_checksum(krb5_data *in_data, /* [inout] */
2987                                                uint32_t gss_flags)
2988 {
2989         unsigned int orig_length = in_data->length;
2990         unsigned int base_cksum_size = GSSAPI_CHECKSUM_SIZE;
2991         char *gss_cksum = NULL;
2992
2993         if (orig_length) {
2994                 /* Extra length field for delgated ticket. */
2995                 base_cksum_size += 4;
2996         }
2997
2998         if ((unsigned int)base_cksum_size + orig_length <
2999                         (unsigned int)base_cksum_size) {
3000                 return EINVAL;
3001         }
3002
3003         gss_cksum = (char *)SMB_MALLOC(base_cksum_size + orig_length);
3004         if (gss_cksum == NULL) {
3005                 return ENOMEM;
3006         }
3007
3008         memset(gss_cksum, '\0', base_cksum_size + orig_length);
3009         SIVAL(gss_cksum, 0, GSSAPI_BNDLENGTH);
3010
3011         /*
3012          * GSS_C_NO_CHANNEL_BINDINGS means 16 zero bytes.
3013          * This matches the behavior of heimdal and mit.
3014          *
3015          * And it is needed to work against some closed source
3016          * SMB servers.
3017          *
3018          * See bug #7883
3019          */
3020         memset(&gss_cksum[4], 0x00, GSSAPI_BNDLENGTH);
3021
3022         SIVAL(gss_cksum, 20, gss_flags);
3023
3024         if (orig_length) {
3025                 SSVAL(gss_cksum, 24, 1); /* The Delegation Option identifier */
3026                 SSVAL(gss_cksum, 26, orig_length);
3027                 /* Copy the kerberos KRB_CRED data */
3028                 memcpy(gss_cksum + 28, in_data->data, orig_length);
3029                 free(in_data->data);
3030                 in_data->data = NULL;
3031                 in_data->length = 0;
3032         }
3033         in_data->data = gss_cksum;
3034         in_data->length = base_cksum_size + orig_length;
3035         return 0;
3036 }
3037 #endif
3038
3039 /*
3040  * We can't use krb5_mk_req because w2k wants the service to be in a particular
3041  * format.
3042  */
3043 static krb5_error_code ads_krb5_mk_req(krb5_context context,
3044                                        krb5_auth_context *auth_context,
3045                                        const krb5_flags ap_req_options,
3046                                        const char *principal,
3047                                        krb5_ccache ccache,
3048                                        krb5_data *outbuf,
3049                                        time_t *expire_time,
3050                                        const char *impersonate_princ_s)
3051 {
3052         krb5_error_code retval;
3053         krb5_principal server;
3054         krb5_principal impersonate_princ = NULL;
3055         krb5_creds *credsp;
3056         krb5_creds creds;
3057         krb5_data in_data;
3058         bool creds_ready = false;
3059         int i = 0, maxtries = 3;
3060         bool ok;
3061
3062         ZERO_STRUCT(in_data);
3063
3064         retval = smb_krb5_parse_name(context, principal, &server);
3065         if (retval != 0) {
3066                 DEBUG(1,("ads_krb5_mk_req: Failed to parse principal %s\n", principal));
3067                 return retval;
3068         }
3069
3070         if (impersonate_princ_s) {
3071                 retval = smb_krb5_parse_name(context, impersonate_princ_s,
3072                                              &impersonate_princ);
3073                 if (retval) {
3074                         DEBUG(1,("ads_krb5_mk_req: Failed to parse principal %s\n", impersonate_princ_s));
3075                         goto cleanup_princ;
3076                 }
3077         }
3078
3079         /* obtain ticket & session key */
3080         ZERO_STRUCT(creds);
3081         if ((retval = krb5_copy_principal(context, server, &creds.server))) {
3082                 DEBUG(1,("ads_krb5_mk_req: krb5_copy_principal failed (%s)\n",
3083                          error_message(retval)));
3084                 goto cleanup_princ;
3085         }
3086
3087         retval = krb5_cc_get_principal(context, ccache, &creds.client);
3088         if (retval != 0) {
3089                 /* This can commonly fail on smbd startup with no ticket in the cache.
3090                  * Report at higher level than 1. */
3091                 DEBUG(3,("ads_krb5_mk_req: krb5_cc_get_principal failed (%s)\n",
3092                          error_message(retval)));
3093                 goto cleanup_creds;
3094         }
3095
3096         while (!creds_ready && (i < maxtries)) {
3097
3098                 retval = smb_krb5_get_credentials(context,
3099                                                   ccache,
3100                                                   creds.client,
3101                                                   creds.server,
3102                                                   impersonate_princ,
3103                                                   &credsp);
3104                 if (retval != 0) {
3105                         DBG_WARNING("smb_krb5_get_credentials failed for %s "
3106                                     "(%s)\n",
3107                                     principal,
3108                                     error_message(retval));
3109                         goto cleanup_creds;
3110                 }
3111
3112                 /* cope with ticket being in the future due to clock skew */
3113                 if ((unsigned)credsp->times.starttime > time(NULL)) {
3114                         time_t t = time(NULL);
3115                         int time_offset =(int)((unsigned)credsp->times.starttime-t);
3116                         DEBUG(4,("ads_krb5_mk_req: Advancing clock by %d seconds to cope with clock skew\n", time_offset));
3117                         krb5_set_real_time(context, t + time_offset + 1, 0);
3118                 }
3119
3120                 ok = ads_cleanup_expired_creds(context, ccache, credsp);
3121                 if (!ok) {
3122                         creds_ready = true;
3123                 }
3124
3125                 i++;
3126         }
3127
3128         DBG_DEBUG("Ticket (%s) in ccache (%s:%s) is valid until: (%s - %u)\n",
3129                   principal,
3130                   krb5_cc_get_type(context, ccache),
3131                   krb5_cc_get_name(context, ccache),
3132                   http_timestring(talloc_tos(),
3133                                   (unsigned)credsp->times.endtime),
3134                   (unsigned)credsp->times.endtime);
3135
3136         if (expire_time) {
3137                 *expire_time = (time_t)credsp->times.endtime;
3138         }
3139
3140         /* Allocate the auth_context. */
3141         retval = ads_setup_auth_context(context, auth_context);
3142         if (retval != 0) {
3143                 DBG_WARNING("ads_setup_auth_context failed (%s)\n",
3144                             error_message(retval));
3145                 goto cleanup_creds;
3146         }
3147
3148 #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE)
3149         {
3150                 uint32_t gss_flags = 0;
3151
3152                 if (credsp->ticket_flags & TKT_FLG_OK_AS_DELEGATE) {
3153                         /*
3154                          * Fetch a forwarded TGT from the KDC so that we can
3155                          * hand off a 2nd ticket as part of the kerberos
3156                          * exchange.
3157                          */
3158
3159                         DBG_INFO("Server marked as OK to delegate to, building "
3160                                  "forwardable TGT\n");
3161
3162                         retval = krb5_auth_con_setuseruserkey(context,
3163                                         *auth_context,
3164                                         &credsp->keyblock );
3165                         if (retval != 0) {
3166                                 DBG_WARNING("krb5_auth_con_setuseruserkey "
3167                                             "failed (%s)\n",
3168                                             error_message(retval));
3169                                 goto cleanup_creds;
3170                         }
3171
3172                         /* Must use a subkey for forwarded tickets. */
3173                         retval = krb5_auth_con_setflags(context,
3174                                                         *auth_context,
3175                                                         KRB5_AUTH_CONTEXT_USE_SUBKEY);
3176                         if (retval != 0) {
3177                                 DBG_WARNING("krb5_auth_con_setflags failed (%s)\n",
3178                                             error_message(retval));
3179                                 goto cleanup_creds;
3180                         }
3181
3182                         retval = krb5_fwd_tgt_creds(context,/* Krb5 context [in] */
3183                                 *auth_context,  /* Authentication context [in] */
3184                                 discard_const_p(char, KRB5_TGS_NAME),  /* Ticket service name ("krbtgt") [in] */
3185                                 credsp->client, /* Client principal for the tgt [in] */
3186                                 credsp->server, /* Server principal for the tgt [in] */
3187                                 ccache,         /* Credential cache to use for storage [in] */
3188                                 1,              /* Turn on for "Forwardable ticket" [in] */
3189                                 &in_data );     /* Resulting response [out] */
3190
3191                         if (retval) {
3192                                 DBG_INFO("krb5_fwd_tgt_creds failed (%s)\n",
3193                                          error_message(retval));
3194
3195                                 /*
3196                                  * This is not fatal. Delete the *auth_context and continue
3197                                  * with krb5_mk_req_extended to get a non-forwardable ticket.
3198                                  */
3199
3200                                 if (in_data.data) {
3201                                         free( in_data.data );
3202                                         in_data.data = NULL;
3203                                         in_data.length = 0;
3204                                 }
3205                                 krb5_auth_con_free(context, *auth_context);
3206                                 *auth_context = NULL;
3207                                 retval = ads_setup_auth_context(context, auth_context);
3208                                 if (retval != 0) {
3209                                         DBG_WARNING("ads_setup_auth_context failed (%s)\n",
3210                                                     error_message(retval));
3211                                         goto cleanup_creds;
3212                                 }
3213                         } else {
3214                                 /* We got a delegated ticket. */
3215                                 gss_flags |= GSS_C_DELEG_FLAG;
3216                         }
3217                 }
3218
3219                 /* Frees and reallocates in_data into a GSS checksum blob. */
3220                 retval = ads_create_gss_checksum(&in_data, gss_flags);
3221                 if (retval != 0) {
3222                         goto cleanup_data;
3223                 }
3224
3225                 /* We always want GSS-checksum types. */
3226                 retval = krb5_auth_con_set_req_cksumtype(context, *auth_context, GSSAPI_CHECKSUM );
3227                 if (retval != 0) {
3228                         DEBUG(1,("krb5_auth_con_set_req_cksumtype failed (%s)\n",
3229                                 error_message(retval)));
3230                         goto cleanup_data;
3231                 }
3232         }
3233 #endif
3234
3235         retval = krb5_mk_req_extended(context, auth_context, ap_req_options,
3236                                       &in_data, credsp, outbuf);
3237         if (retval != 0) {
3238                 DBG_WARNING("krb5_mk_req_extended failed (%s)\n",
3239                             error_message(retval));
3240         }
3241
3242 #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE)
3243 cleanup_data:
3244 #endif
3245
3246         if (in_data.data) {
3247                 free( in_data.data );
3248                 in_data.length = 0;
3249         }
3250
3251         krb5_free_creds(context, credsp);
3252
3253 cleanup_creds:
3254         krb5_free_cred_contents(context, &creds);
3255
3256 cleanup_princ:
3257         krb5_free_principal(context, server);
3258         if (impersonate_princ) {
3259                 krb5_free_principal(context, impersonate_princ);
3260         }
3261
3262         return retval;
3263 }
3264
3265 /*
3266   get a kerberos5 ticket for the given service
3267 */
3268 int ads_krb5_cli_get_ticket(TALLOC_CTX *mem_ctx,
3269                             const char *principal,
3270                             time_t time_offset,
3271                             DATA_BLOB *ticket,
3272                             DATA_BLOB *session_key_krb5,
3273                             uint32_t extra_ap_opts, const char *ccname,
3274                             time_t *tgs_expire,
3275                             const char *impersonate_princ_s)
3276 {
3277         krb5_error_code retval;
3278         krb5_data packet;
3279         krb5_context context = NULL;
3280         krb5_ccache ccdef = NULL;
3281         krb5_auth_context auth_context = NULL;
3282         krb5_enctype enc_types[] = {
3283 #ifdef HAVE_ENCTYPE_AES256_CTS_HMAC_SHA1_96
3284                 ENCTYPE_AES256_CTS_HMAC_SHA1_96,
3285 #endif
3286 #ifdef HAVE_ENCTYPE_AES128_CTS_HMAC_SHA1_96
3287                 ENCTYPE_AES128_CTS_HMAC_SHA1_96,
3288 #endif
3289                 ENCTYPE_ARCFOUR_HMAC,
3290                 ENCTYPE_DES_CBC_MD5,
3291                 ENCTYPE_DES_CBC_CRC,
3292                 ENCTYPE_NULL};
3293         bool ok;
3294
3295         initialize_krb5_error_table();
3296         retval = krb5_init_context(&context);
3297         if (retval != 0) {
3298                 DBG_WARNING("krb5_init_context failed (%s)\n",
3299                             error_message(retval));
3300                 goto failed;
3301         }
3302
3303         if (time_offset != 0) {
3304                 krb5_set_real_time(context, time(NULL) + time_offset, 0);
3305         }
3306
3307         retval = krb5_cc_resolve(context,
3308                                  ccname ? ccname : krb5_cc_default_name(context),
3309                                  &ccdef);
3310         if (retval != 0) {
3311                 DBG_WARNING("krb5_cc_default failed (%s)\n",
3312                             error_message(retval));
3313                 goto failed;
3314         }
3315
3316         retval = krb5_set_default_tgs_ktypes(context, enc_types);
3317         if (retval != 0) {
3318                 DBG_WARNING("krb5_set_default_tgs_ktypes failed (%s)\n",
3319                             error_message(retval));
3320                 goto failed;
3321         }
3322
3323         retval = ads_krb5_mk_req(context,
3324                                  &auth_context,
3325                                  AP_OPTS_USE_SUBKEY | (krb5_flags)extra_ap_opts,
3326                                  principal,
3327                                  ccdef,
3328                                  &packet,
3329                                  tgs_expire,
3330                                  impersonate_princ_s);
3331         if (retval != 0) {
3332                 goto failed;
3333         }
3334
3335         ok = smb_krb5_get_smb_session_key(mem_ctx,
3336                                           context,
3337                                           auth_context,
3338                                           session_key_krb5,
3339                                           false);
3340         if (!ok) {
3341                 retval = ENOMEM;
3342                 goto failed;
3343         }
3344
3345         *ticket = data_blob_talloc(mem_ctx, packet.data, packet.length);
3346
3347         smb_krb5_free_data_contents(context, &packet);
3348
3349 failed:
3350
3351         if (context) {
3352                 if (ccdef) {
3353                         krb5_cc_close(context, ccdef);
3354                 }
3355                 if (auth_context) {
3356                         krb5_auth_con_free(context, auth_context);
3357                 }
3358                 krb5_free_context(context);
3359         }
3360
3361         return retval;
3362 }
3363
3364 #else /* HAVE_KRB5 */
3365 /* This saves a few linking headaches */
3366 int ads_krb5_cli_get_ticket(TALLOC_CTX *mem_ctx,
3367                             const char *principal,
3368                             time_t time_offset,
3369                             DATA_BLOB *ticket,
3370                             DATA_BLOB *session_key_krb5,
3371                             uint32_t extra_ap_opts, const char *ccname,
3372                             time_t *tgs_expire,
3373                             const char *impersonate_princ_s)
3374 {
3375          DEBUG(0,("NO KERBEROS SUPPORT\n"));
3376          return 1;
3377 }
3378
3379 #endif /* HAVE_KRB5 */