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 #include "lib/util/asn1.h"
  27
  28 #ifdef HAVE_COM_ERR_H
  29 #include <com_err.h>
  30 #endif /* HAVE_COM_ERR_H */
  31
  32 #ifndef KRB5_AUTHDATA_WIN2K_PAC
  33 #define KRB5_AUTHDATA_WIN2K_PAC 128
  34 #endif
  35
  36 #ifndef KRB5_AUTHDATA_IF_RELEVANT
  37 #define KRB5_AUTHDATA_IF_RELEVANT 1
  38 #endif
  39
  40 #ifdef HAVE_KRB5
  41
  42 #define GSSAPI_CHECKSUM      0x8003             /* Checksum type value for Kerberos */
  43 #define GSSAPI_BNDLENGTH     16                 /* Bind Length (rfc-1964 pg.3) */
  44 #define GSSAPI_CHECKSUM_SIZE (4+GSSAPI_BNDLENGTH+4) /* Length of bind length,
  45                                                         bind field, flags field. */
  46 #define GSS_C_DELEG_FLAG 1
  47
  48 /* MIT krb5 1.7beta3 (in Ubuntu Karmic) is missing the prototype,
  49    but still has the symbol */
  50 #if !HAVE_DECL_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE
  51 krb5_error_code krb5_auth_con_set_req_cksumtype(
  52         krb5_context     context,
  53         krb5_auth_context      auth_context,
  54         krb5_cksumtype     cksumtype);
  55 #endif
  56
  57 #if !defined(SMB_MALLOC)
  58 #undef malloc
  59 #define SMB_MALLOC(s) malloc((s))
  60 #endif
  61
  62 #ifndef SMB_STRDUP
  63 #define SMB_STRDUP(s) strdup(s)
  64 #endif
  65
  66 /**********************************************************
  67  * MISSING FUNCTIONS
  68  **********************************************************/
  69
  70 #if !defined(HAVE_KRB5_SET_DEFAULT_TGS_KTYPES)
  71
  72 #if defined(HAVE_KRB5_SET_DEFAULT_TGS_ENCTYPES)
  73
  74 /* With MIT kerberos, we should use krb5_set_default_tgs_enctypes in preference
  75  * to krb5_set_default_tgs_ktypes. See
  76  *         http://lists.samba.org/archive/samba-technical/2006-July/048271.html
  77  *
  78  * If the MIT libraries are not exporting internal symbols, we will end up in
  79  * this branch, which is correct. Otherwise we will continue to use the
  80  * internal symbol
  81  */
  82  krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc)
  83 {
  84     return krb5_set_default_tgs_enctypes(ctx, enc);
  85 }
  86
  87 #elif defined(HAVE_KRB5_SET_DEFAULT_IN_TKT_ETYPES)
  88
  89 /* Heimdal */
  90  krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc)
  91 {
  92         return krb5_set_default_in_tkt_etypes(ctx, enc);
  93 }
  94
  95 #endif /* HAVE_KRB5_SET_DEFAULT_TGS_ENCTYPES */
  96
  97 #endif /* HAVE_KRB5_SET_DEFAULT_TGS_KTYPES */
  98
  99
 100 #if defined(HAVE_KRB5_AUTH_CON_SETKEY) && !defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY)
 101 krb5_error_code krb5_auth_con_setuseruserkey(krb5_context context,
 102                                              krb5_auth_context auth_context,
 103                                              krb5_keyblock *keyblock)
 104 {
 105         return krb5_auth_con_setkey(context, auth_context, keyblock);
 106 }
 107 #endif
 108
 109 #if !defined(HAVE_KRB5_FREE_UNPARSED_NAME)
 110 void krb5_free_unparsed_name(krb5_context context, char *val)
 111 {
 112         SAFE_FREE(val);
 113 }
 114 #endif
 115
 116 #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING) && !defined(HAVE_KRB5_PRINC_COMPONENT)
 117 const krb5_data *krb5_princ_component(krb5_context context,
 118                                       krb5_principal principal, int i);
 119
 120 const krb5_data *krb5_princ_component(krb5_context context,
 121                                       krb5_principal principal, int i)
 122 {
 123         static krb5_data kdata;
 124
 125         kdata.data = discard_const_p(char, krb5_principal_get_comp_string(context, principal, i));
 126         kdata.length = strlen((const char *)kdata.data);
 127         return &kdata;
 128 }
 129 #endif
 130
 131
 132 /**********************************************************
 133  * WRAPPING FUNCTIONS
 134  **********************************************************/
 135
 136 #if defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS)
 137 /* HEIMDAL */
 138
 139 /**
 140  * @brief Stores the address of a 'struct sockaddr_storage' a krb5_address
 141  *
 142  * @param[in]  paddr    A pointer to a 'struct sockaddr_storage to extract the
 143  *                      address from.
 144  *
 145  * @param[out] pkaddr   A Kerberos address to store tha address in.
 146  *
 147  * @return True on success, false if an error occured.
 148  */
 149 bool smb_krb5_sockaddr_to_kaddr(struct sockaddr_storage *paddr,
 150                                 krb5_address *pkaddr)
 151 {
 152         memset(pkaddr, '\0', sizeof(krb5_address));
 153 #if defined(HAVE_IPV6) && defined(KRB5_ADDRESS_INET6)
 154         if (paddr->ss_family == AF_INET6) {
 155                 pkaddr->addr_type = KRB5_ADDRESS_INET6;
 156                 pkaddr->address.length = sizeof(((struct sockaddr_in6 *)paddr)->sin6_addr);
 157                 pkaddr->address.data = (char *)&(((struct sockaddr_in6 *)paddr)->sin6_addr);
 158                 return true;
 159         }
 160 #endif
 161         if (paddr->ss_family == AF_INET) {
 162                 pkaddr->addr_type = KRB5_ADDRESS_INET;
 163                 pkaddr->address.length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
 164                 pkaddr->address.data = (char *)&(((struct sockaddr_in *)paddr)->sin_addr);
 165                 return true;
 166         }
 167         return false;
 168 }
 169 #elif defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS)
 170 /* MIT */
 171
 172 /**
 173  * @brief Stores the address of a 'struct sockaddr_storage' a krb5_address
 174  *
 175  * @param[in]  paddr    A pointer to a 'struct sockaddr_storage to extract the
 176  *                      address from.
 177  *
 178  * @param[in]  pkaddr A Kerberos address to store tha address in.
 179  *
 180  * @return True on success, false if an error occured.
 181  */
 182 bool smb_krb5_sockaddr_to_kaddr(struct sockaddr_storage *paddr,
 183                                 krb5_address *pkaddr)
 184 {
 185         memset(pkaddr, '\0', sizeof(krb5_address));
 186 #if defined(HAVE_IPV6) && defined(ADDRTYPE_INET6)
 187         if (paddr->ss_family == AF_INET6) {
 188                 pkaddr->addrtype = ADDRTYPE_INET6;
 189                 pkaddr->length = sizeof(((struct sockaddr_in6 *)paddr)->sin6_addr);
 190                 pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in6 *)paddr)->sin6_addr);
 191                 return true;
 192         }
 193 #endif
 194         if (paddr->ss_family == AF_INET) {
 195                 pkaddr->addrtype = ADDRTYPE_INET;
 196                 pkaddr->length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
 197                 pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in *)paddr)->sin_addr);
 198                 return true;
 199         }
 200         return false;
 201 }
 202 #else
 203 #error UNKNOWN_ADDRTYPE
 204 #endif
 205
 206 krb5_error_code smb_krb5_mk_error(krb5_context context,
 207                                   krb5_error_code error_code,
 208                                   const char *e_text,
 209                                   krb5_data *e_data,
 210                                   krb5_data *enc_err)
 211 {
 212         krb5_error_code code = EINVAL;
 213 #ifdef SAMBA4_USES_HEIMDAL
 214         code = krb5_mk_error(context,
 215                              error_code,
 216                              e_text,
 217                              e_data,
 218                              NULL, /* client */
 219                              NULL, /* server */
 220                              NULL, /* client_time */
 221                              NULL, /* client_usec */
 222                              enc_err);
 223 #else
 224         krb5_error dec_err = {
 225                 .error = error_code,
 226         };
 227
 228         if (e_text != NULL) {
 229                 dec_err.text.length = strlen(e_text);
 230                 dec_err.text.data = discard_const_p(char, e_text);
 231         }
 232         if (e_data != NULL) {
 233                 dec_err.e_data = *e_data;
 234         }
 235
 236         code = krb5_mk_error(context,
 237                              &dec_err,
 238                              enc_err);
 239 #endif
 240         return code;
 241 }
 242
 243 /**
 244 * @brief Create a keyblock based on input parameters
 245 *
 246 * @param context        The krb5_context
 247 * @param host_princ     The krb5_principal to use
 248 * @param salt           The optional salt, if omitted, salt is calculated with
 249 *                       the provided principal.
 250 * @param password       The krb5_data containing the password
 251 * @param enctype        The krb5_enctype to use for the keyblock generation
 252 * @param key            The returned krb5_keyblock, caller needs to free with
 253 *                       krb5_free_keyblock().
 254 *
 255 * @return krb5_error_code
 256 */
 257 int smb_krb5_create_key_from_string(krb5_context context,
 258                                     krb5_const_principal host_princ,
 259                                     krb5_data *salt,
 260                                     krb5_data *password,
 261                                     krb5_enctype enctype,
 262                                     krb5_keyblock *key)
 263 {
 264         int ret = 0;
 265
 266         if (host_princ == NULL && salt == NULL) {
 267                 return -1;
 268         }
 269
 270 #if defined(HAVE_KRB5_PRINCIPAL2SALT) && defined(HAVE_KRB5_C_STRING_TO_KEY)
 271 {/* MIT */
 272         krb5_data _salt;
 273
 274         if (salt == NULL) {
 275                 ret = krb5_principal2salt(context, host_princ, &_salt);
 276                 if (ret) {
 277                         DEBUG(1,("krb5_principal2salt failed (%s)\n", error_message(ret)));
 278                         return ret;
 279                 }
 280         } else {
 281                 _salt = *salt;
 282         }
 283         ret = krb5_c_string_to_key(context, enctype, password, &_salt, key);
 284         if (salt == NULL) {
 285                 SAFE_FREE(_salt.data);
 286         }
 287 }
 288 #elif defined(HAVE_KRB5_GET_PW_SALT) && defined(HAVE_KRB5_STRING_TO_KEY_SALT)
 289 {/* Heimdal */
 290         krb5_salt _salt;
 291
 292         if (salt == NULL) {
 293                 ret = krb5_get_pw_salt(context, host_princ, &_salt);
 294                 if (ret) {
 295                         DEBUG(1,("krb5_get_pw_salt failed (%s)\n", error_message(ret)));
 296                         return ret;
 297                 }
 298         } else {
 299                 _salt.saltvalue = *salt;
 300                 _salt.salttype = KRB5_PW_SALT;
 301         }
 302
 303         ret = krb5_string_to_key_salt(context, enctype, (const char *)password->data, _salt, key);
 304         if (salt == NULL) {
 305                 krb5_free_salt(context, _salt);
 306         }
 307 }
 308 #else
 309 #error UNKNOWN_CREATE_KEY_FUNCTIONS
 310 #endif
 311         return ret;
 312 }
 313
 314 /**
 315 * @brief Create a salt for a given principal
 316 *
 317 * @param context        The initialized krb5_context
 318 * @param host_princ     The krb5_principal to create the salt for
 319 * @param psalt          A pointer to a krb5_data struct
 320 *
 321 * caller has to free the contents of psalt with smb_krb5_free_data_contents
 322 * when function has succeeded
 323 *
 324 * @return krb5_error_code, returns 0 on success, error code otherwise
 325 */
 326
 327 int smb_krb5_get_pw_salt(krb5_context context,
 328                          krb5_const_principal host_princ,
 329                          krb5_data *psalt)
 330 #if defined(HAVE_KRB5_GET_PW_SALT)
 331 /* Heimdal */
 332 {
 333         int ret;
 334         krb5_salt salt;
 335
 336         ret = krb5_get_pw_salt(context, host_princ, &salt);
 337         if (ret) {
 338                 return ret;
 339         }
 340
 341         psalt->data = salt.saltvalue.data;
 342         psalt->length = salt.saltvalue.length;
 343
 344         return ret;
 345 }
 346 #elif defined(HAVE_KRB5_PRINCIPAL2SALT)
 347 /* MIT */
 348 {
 349         return krb5_principal2salt(context, host_princ, psalt);
 350 }
 351 #else
 352 #error UNKNOWN_SALT_FUNCTIONS
 353 #endif
 354
 355 #if defined(HAVE_KRB5_GET_PERMITTED_ENCTYPES)
 356 /**
 357  * @brief Get a list of encryption types allowed for session keys
 358  *
 359  * @param[in]  context  The library context
 360  *
 361  * @param[in]  enctypes An allocated, zero-terminated list of encryption types
 362  *
 363  * This function returns an allocated list of encryption types allowed for
 364  * session keys.
 365  *
 366  * Use free() to free the enctypes when it is no longer needed.
 367  *
 368  * @retval 0 Success; otherwise - Kerberos error codes
 369  */
 370 krb5_error_code smb_krb5_get_allowed_etypes(krb5_context context,
 371                                             krb5_enctype **enctypes)
 372 {
 373         return krb5_get_permitted_enctypes(context, enctypes);
 374 }
 375 #elif defined(HAVE_KRB5_GET_DEFAULT_IN_TKT_ETYPES)
 376 krb5_error_code smb_krb5_get_allowed_etypes(krb5_context context,
 377                                             krb5_enctype **enctypes)
 378 {
 379 #ifdef HAVE_KRB5_PDU_NONE_DECL
 380         return krb5_get_default_in_tkt_etypes(context, KRB5_PDU_NONE, enctypes);
 381 #else
 382         return krb5_get_default_in_tkt_etypes(context, enctypes);
 383 #endif
 384 }
 385 #else
 386 #error UNKNOWN_GET_ENCTYPES_FUNCTIONS
 387 #endif
 388
 389 bool unwrap_edata_ntstatus(TALLOC_CTX *mem_ctx,
 390                            DATA_BLOB *edata,
 391                            DATA_BLOB *edata_out)
 392 {
 393         DATA_BLOB edata_contents;
 394         ASN1_DATA *data;
 395         int edata_type;
 396
 397         if (!edata->length) {
 398                 return false;
 399         }
 400
 401         data = asn1_init(mem_ctx);
 402         if (data == NULL) {
 403                 return false;
 404         }
 405
 406         if (!asn1_load(data, *edata)) goto err;
 407         if (!asn1_start_tag(data, ASN1_SEQUENCE(0))) goto err;
 408         if (!asn1_start_tag(data, ASN1_CONTEXT(1))) goto err;
 409         if (!asn1_read_Integer(data, &edata_type)) goto err;
 410
 411         if (edata_type != KRB5_PADATA_PW_SALT) {
 412                 DEBUG(0,("edata is not of required type %d but of type %d\n",
 413                         KRB5_PADATA_PW_SALT, edata_type));
 414                 goto err;
 415         }
 416
 417         if (!asn1_start_tag(data, ASN1_CONTEXT(2))) goto err;
 418         if (!asn1_read_OctetString(data, talloc_tos(), &edata_contents)) goto err;
 419         if (!asn1_end_tag(data)) goto err;
 420         if (!asn1_end_tag(data)) goto err;
 421         if (!asn1_end_tag(data)) goto err;
 422         asn1_free(data);
 423
 424         *edata_out = data_blob_talloc(mem_ctx, edata_contents.data, edata_contents.length);
 425
 426         data_blob_free(&edata_contents);
 427
 428         return true;
 429
 430   err:
 431
 432         asn1_free(data);
 433         return false;
 434 }
 435
 436
 437 /**************************************************************
 438  krb5_parse_name that takes a UNIX charset.
 439 **************************************************************/
 440
 441 krb5_error_code smb_krb5_parse_name(krb5_context context,
 442                                 const char *name, /* in unix charset */
 443                                 krb5_principal *principal)
 444 {
 445         krb5_error_code ret;
 446         char *utf8_name;
 447         size_t converted_size;
 448         TALLOC_CTX *frame = talloc_stackframe();
 449
 450         if (!push_utf8_talloc(frame, &utf8_name, name, &converted_size)) {
 451                 talloc_free(frame);
 452                 return ENOMEM;
 453         }
 454
 455         ret = krb5_parse_name(context, utf8_name, principal);
 456         TALLOC_FREE(frame);
 457         return ret;
 458 }
 459
 460 /**************************************************************
 461  krb5_parse_name that returns a UNIX charset name. Must
 462  be freed with talloc_free() call.
 463 **************************************************************/
 464
 465 krb5_error_code smb_krb5_unparse_name(TALLOC_CTX *mem_ctx,
 466                                       krb5_context context,
 467                                       krb5_const_principal principal,
 468                                       char **unix_name)
 469 {
 470         krb5_error_code ret;
 471         char *utf8_name;
 472         size_t converted_size;
 473
 474         *unix_name = NULL;
 475         ret = krb5_unparse_name(context, principal, &utf8_name);
 476         if (ret) {
 477                 return ret;
 478         }
 479
 480         if (!pull_utf8_talloc(mem_ctx, unix_name, utf8_name, &converted_size)) {
 481                 krb5_free_unparsed_name(context, utf8_name);
 482                 return ENOMEM;
 483         }
 484         krb5_free_unparsed_name(context, utf8_name);
 485         return 0;
 486 }
 487
 488 krb5_error_code smb_krb5_parse_name_norealm(krb5_context context,
 489                                             const char *name,
 490                                             krb5_principal *principal)
 491 {
 492         /* we are cheating here because parse_name will in fact set the realm.
 493          * We don't care as the only caller of smb_krb5_parse_name_norealm
 494          * ignores the realm anyway when calling
 495          * smb_krb5_principal_compare_any_realm later - Guenther */
 496
 497         return smb_krb5_parse_name(context, name, principal);
 498 }
 499
 500 bool smb_krb5_principal_compare_any_realm(krb5_context context,
 501                                           krb5_const_principal princ1,
 502                                           krb5_const_principal princ2)
 503 {
 504         return krb5_principal_compare_any_realm(context, princ1, princ2);
 505 }
 506
 507 /**
 508  * @brief Free the contents of a krb5_data structure and zero the data field.
 509  *
 510  * @param[in]  context  The krb5 context
 511  *
 512  * @param[in]  pdata    The data structure to free contents of
 513  *
 514  * This function frees the contents, not the structure itself.
 515  */
 516 void smb_krb5_free_data_contents(krb5_context context, krb5_data *pdata)
 517 {
 518 #if defined(HAVE_KRB5_FREE_DATA_CONTENTS)
 519         if (pdata->data) {
 520                 krb5_free_data_contents(context, pdata);
 521         }
 522 #elif defined(HAVE_KRB5_DATA_FREE)
 523         krb5_data_free(context, pdata);
 524 #else
 525         SAFE_FREE(pdata->data);
 526 #endif
 527 }
 528
 529 /*
 530  * @brief copy a buffer into a krb5_data struct
 531  *
 532  * @param[in] p                 The krb5_data
 533  * @param[in] data              The data to copy
 534  * @param[in] length            The length of the data to copy
 535  * @return krb5_error_code
 536  *
 537  * Caller has to free krb5_data with smb_krb5_free_data_contents().
 538  */
 539 krb5_error_code smb_krb5_copy_data_contents(krb5_data *p,
 540                                             const void *data,
 541                                             size_t len)
 542 {
 543 #if defined(HAVE_KRB5_DATA_COPY)
 544         return krb5_data_copy(p, data, len);
 545 #else
 546         if (len) {
 547                 p->data = malloc(len);
 548                 if (p->data == NULL) {
 549                         return ENOMEM;
 550                 }
 551                 memmove(p->data, data, len);
 552         } else {
 553                 p->data = NULL;
 554         }
 555         p->length = len;
 556         p->magic = KV5M_DATA;
 557         return 0;
 558 #endif
 559 }
 560
 561 bool smb_krb5_get_smb_session_key(TALLOC_CTX *mem_ctx,
 562                                   krb5_context context,
 563                                   krb5_auth_context auth_context,
 564                                   DATA_BLOB *session_key,
 565                                   bool remote)
 566 {
 567         krb5_keyblock *skey = NULL;
 568         krb5_error_code err = 0;
 569         bool ret = false;
 570
 571         if (remote) {
 572 #ifdef HAVE_KRB5_AUTH_CON_GETRECVSUBKEY
 573                 err = krb5_auth_con_getrecvsubkey(context,
 574                                                   auth_context,
 575                                                   &skey);
 576 #else /* HAVE_KRB5_AUTH_CON_GETRECVSUBKEY */
 577                 err = krb5_auth_con_getremotesubkey(context,
 578                                                     auth_context, &skey);
 579 #endif /* HAVE_KRB5_AUTH_CON_GETRECVSUBKEY */
 580         } else {
 581 #ifdef HAVE_KRB5_AUTH_CON_GETSENDSUBKEY
 582                 err = krb5_auth_con_getsendsubkey(context,
 583                                                   auth_context,
 584                                                   &skey);
 585 #else /* HAVE_KRB5_AUTH_CON_GETSENDSUBKEY */
 586                 err = krb5_auth_con_getlocalsubkey(context,
 587                                                    auth_context, &skey);
 588 #endif /* HAVE_KRB5_AUTH_CON_GETSENDSUBKEY */
 589         }
 590
 591         if (err || skey == NULL) {
 592                 DEBUG(10, ("KRB5 error getting session key %d\n", err));
 593                 goto done;
 594         }
 595
 596         DEBUG(10, ("Got KRB5 session key of length %d\n",
 597                    (int)KRB5_KEY_LENGTH(skey)));
 598
 599         *session_key = data_blob_talloc(mem_ctx,
 600                                          KRB5_KEY_DATA(skey),
 601                                          KRB5_KEY_LENGTH(skey));
 602         dump_data_pw("KRB5 Session Key:\n",
 603                      session_key->data,
 604                      session_key->length);
 605
 606         ret = true;
 607
 608 done:
 609         if (skey) {
 610                 krb5_free_keyblock(context, skey);
 611         }
 612
 613         return ret;
 614 }
 615
 616
 617 /**
 618  * @brief Get talloced string component of a principal
 619  *
 620  * @param[in] mem_ctx           The TALLOC_CTX
 621  * @param[in] context           The krb5_context
 622  * @param[in] principal         The principal
 623  * @param[in] component         The component
 624  * @return string component
 625  *
 626  * Caller must talloc_free if the return value is not NULL.
 627  *
 628  */
 629 char *smb_krb5_principal_get_comp_string(TALLOC_CTX *mem_ctx,
 630                                          krb5_context context,
 631                                          krb5_const_principal principal,
 632                                          unsigned int component)
 633 {
 634 #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING)
 635         return talloc_strdup(mem_ctx, krb5_principal_get_comp_string(context, principal, component));
 636 #else
 637         krb5_data *data;
 638
 639         if (component >= krb5_princ_size(context, principal)) {
 640                 return NULL;
 641         }
 642
 643         data = krb5_princ_component(context, principal, component);
 644         if (data == NULL) {
 645                 return NULL;
 646         }
 647
 648         return talloc_strndup(mem_ctx, data->data, data->length);
 649 #endif
 650 }
 651
 652 /**
 653  * @brief
 654  *
 655  * @param[in]  ccache_string A string pointing to the cache to renew the ticket
 656  *                           (e.g. FILE:/tmp/krb5cc_0) or NULL. If the principal
 657  *                           ccache has not been specified, the default ccache
 658  *                           will be used.
 659  *
 660  * @param[in]  client_string The client principal string (e.g. user@SAMBA.SITE)
 661  *                           or NULL. If the principal string has not been
 662  *                           specified, the principal from the ccache will be
 663  *                           retrieved.
 664  *
 665  * @param[in]  service_string The service ticket string
 666  *                            (e.g. krbtgt/SAMBA.SITE@SAMBA.SITE) or NULL. If
 667  *                            the sevice ticket is specified, it is parsed (
 668  *                            with the realm part ignored) and used as the
 669  *                            server principal of the credential. Otherwise
 670  *                            the ticket-granting service is used.
 671  *
 672  * @param[in]  expire_time    A pointer to store the credentials end time or
 673  *                            NULL.
 674  *
 675  * @return 0 on Succes, a Kerberos error code otherwise.
 676  */
 677 krb5_error_code smb_krb5_renew_ticket(const char *ccache_string,
 678                                       const char *client_string,
 679                                       const char *service_string,
 680                                       time_t *expire_time)
 681 {
 682         krb5_error_code ret;
 683         krb5_context context = NULL;
 684         krb5_ccache ccache = NULL;
 685         krb5_principal client = NULL;
 686         krb5_creds creds, creds_in;
 687
 688         ZERO_STRUCT(creds);
 689         ZERO_STRUCT(creds_in);
 690
 691         initialize_krb5_error_table();
 692         ret = krb5_init_context(&context);
 693         if (ret) {
 694                 goto done;
 695         }
 696
 697         if (!ccache_string) {
 698                 ccache_string = krb5_cc_default_name(context);
 699         }
 700
 701         if (!ccache_string) {
 702                 ret = EINVAL;
 703                 goto done;
 704         }
 705
 706         DEBUG(10,("smb_krb5_renew_ticket: using %s as ccache\n", ccache_string));
 707
 708         /* FIXME: we should not fall back to defaults */
 709         ret = krb5_cc_resolve(context, discard_const_p(char, ccache_string), &ccache);
 710         if (ret) {
 711                 goto done;
 712         }
 713
 714         if (client_string) {
 715                 ret = smb_krb5_parse_name(context, client_string, &client);
 716                 if (ret) {
 717                         goto done;
 718                 }
 719         } else {
 720                 ret = krb5_cc_get_principal(context, ccache, &client);
 721                 if (ret) {
 722                         goto done;
 723                 }
 724         }
 725
 726         ret = krb5_get_renewed_creds(context, &creds, client, ccache, discard_const_p(char, service_string));
 727         if (ret) {
 728                 DEBUG(10,("smb_krb5_renew_ticket: krb5_get_kdc_cred failed: %s\n", error_message(ret)));
 729                 goto done;
 730         }
 731
 732         /* hm, doesn't that create a new one if the old one wasn't there? - Guenther */
 733         ret = krb5_cc_initialize(context, ccache, client);
 734         if (ret) {
 735                 goto done;
 736         }
 737
 738         ret = krb5_cc_store_cred(context, ccache, &creds);
 739
 740         if (expire_time) {
 741                 *expire_time = (time_t) creds.times.endtime;
 742         }
 743
 744 done:
 745         krb5_free_cred_contents(context, &creds_in);
 746         krb5_free_cred_contents(context, &creds);
 747
 748         if (client) {
 749                 krb5_free_principal(context, client);
 750         }
 751         if (ccache) {
 752                 krb5_cc_close(context, ccache);
 753         }
 754         if (context) {
 755                 krb5_free_context(context);
 756         }
 757
 758         return ret;
 759 }
 760
 761 /**
 762  * @brief Free the data stored in an smb_krb5_addresses structure.
 763  *
 764  * @param[in]  context  The library context
 765  *
 766  * @param[in]  addr     The address structure to free.
 767  *
 768  * @return 0 on success, a Kerberos error code otherwise.
 769  */
 770 krb5_error_code smb_krb5_free_addresses(krb5_context context,
 771                                         smb_krb5_addresses *addr)
 772 {
 773         krb5_error_code ret = 0;
 774         if (addr == NULL) {
 775                 return ret;
 776         }
 777 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
 778         krb5_free_addresses(context, addr->addrs);
 779 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
 780         ret = krb5_free_addresses(context, addr->addrs);
 781         SAFE_FREE(addr->addrs);
 782 #endif
 783         SAFE_FREE(addr);
 784         addr = NULL;
 785         return ret;
 786 }
 787
 788 #define MAX_NETBIOSNAME_LEN 16
 789
 790 /**
 791  * @brief Add a netbios name to the array of addresses
 792  *
 793  * @param[in]  kerb_addr A pointer to the smb_krb5_addresses to add the
 794  *                       netbios name to.
 795  *
 796  * @param[in]  netbios_name The netbios name to add.
 797  *
 798  * @return 0 on success, a Kerberos error code otherwise.
 799  */
 800 krb5_error_code smb_krb5_gen_netbios_krb5_address(smb_krb5_addresses **kerb_addr,
 801                                                    const char *netbios_name)
 802 {
 803         krb5_error_code ret = 0;
 804         char buf[MAX_NETBIOSNAME_LEN];
 805         int len;
 806 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
 807         krb5_address **addrs = NULL;
 808 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
 809         krb5_addresses *addrs = NULL;
 810 #endif
 811
 812         *kerb_addr = (smb_krb5_addresses *)SMB_MALLOC(sizeof(smb_krb5_addresses));
 813         if (*kerb_addr == NULL) {
 814                 return ENOMEM;
 815         }
 816
 817         /* temporarily duplicate put_name() code here to avoid dependency
 818          * issues for a 5 lines function */
 819         len = strlen(netbios_name);
 820         memcpy(buf, netbios_name,
 821                 (len < MAX_NETBIOSNAME_LEN) ? len : MAX_NETBIOSNAME_LEN - 1);
 822         if (len < MAX_NETBIOSNAME_LEN - 1) {
 823                 memset(buf + len, ' ', MAX_NETBIOSNAME_LEN - 1 - len);
 824         }
 825         buf[MAX_NETBIOSNAME_LEN - 1] = 0x20;
 826
 827 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
 828         {
 829                 int num_addr = 2;
 830
 831                 addrs = (krb5_address **)SMB_MALLOC(sizeof(krb5_address *) * num_addr);
 832                 if (addrs == NULL) {
 833                         SAFE_FREE(*kerb_addr);
 834                         return ENOMEM;
 835                 }
 836
 837                 memset(addrs, 0, sizeof(krb5_address *) * num_addr);
 838
 839                 addrs[0] = (krb5_address *)SMB_MALLOC(sizeof(krb5_address));
 840                 if (addrs[0] == NULL) {
 841                         SAFE_FREE(addrs);
 842                         SAFE_FREE(*kerb_addr);
 843                         return ENOMEM;
 844                 }
 845
 846                 addrs[0]->magic = KV5M_ADDRESS;
 847                 addrs[0]->addrtype = KRB5_ADDR_NETBIOS;
 848                 addrs[0]->length = MAX_NETBIOSNAME_LEN;
 849                 addrs[0]->contents = (unsigned char *)SMB_MALLOC(addrs[0]->length);
 850                 if (addrs[0]->contents == NULL) {
 851                         SAFE_FREE(addrs[0]);
 852                         SAFE_FREE(addrs);
 853                         SAFE_FREE(*kerb_addr);
 854                         return ENOMEM;
 855                 }
 856
 857                 memcpy(addrs[0]->contents, buf, addrs[0]->length);
 858
 859                 addrs[1] = NULL;
 860         }
 861 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
 862         {
 863                 addrs = (krb5_addresses *)SMB_MALLOC(sizeof(krb5_addresses));
 864                 if (addrs == NULL) {
 865                         SAFE_FREE(*kerb_addr);
 866                         return ENOMEM;
 867                 }
 868
 869                 memset(addrs, 0, sizeof(krb5_addresses));
 870
 871                 addrs->len = 1;
 872                 addrs->val = (krb5_address *)SMB_MALLOC(sizeof(krb5_address));
 873                 if (addrs->val == NULL) {
 874                         SAFE_FREE(addrs);
 875                         SAFE_FREE(kerb_addr);
 876                         return ENOMEM;
 877                 }
 878
 879                 addrs->val[0].addr_type = KRB5_ADDR_NETBIOS;
 880                 addrs->val[0].address.length = MAX_NETBIOSNAME_LEN;
 881                 addrs->val[0].address.data = (unsigned char *)SMB_MALLOC(addrs->val[0].address.length);
 882                 if (addrs->val[0].address.data == NULL) {
 883                         SAFE_FREE(addrs->val);
 884                         SAFE_FREE(addrs);
 885                         SAFE_FREE(*kerb_addr);
 886                         return ENOMEM;
 887                 }
 888
 889                 memcpy(addrs->val[0].address.data, buf, addrs->val[0].address.length);
 890         }
 891 #else
 892 #error UNKNOWN_KRB5_ADDRESS_FORMAT
 893 #endif
 894         (*kerb_addr)->addrs = addrs;
 895
 896         return ret;
 897 }
 898
 899 krb5_enctype smb_krb5_kt_get_enctype_from_entry(krb5_keytab_entry *kt_entry)
 900 {
 901         return KRB5_KEY_TYPE(KRB5_KT_KEY(kt_entry));
 902 }
 903
 904 krb5_error_code smb_krb5_kt_free_entry(krb5_context context,
 905                                         krb5_keytab_entry *kt_entry)
 906 {
 907 /* Try krb5_free_keytab_entry_contents first, since
 908  * MIT Kerberos >= 1.7 has both krb5_free_keytab_entry_contents and
 909  * krb5_kt_free_entry but only has a prototype for the first, while the
 910  * second is considered private.
 911  */
 912 #if defined(HAVE_KRB5_FREE_KEYTAB_ENTRY_CONTENTS)
 913         return krb5_free_keytab_entry_contents(context, kt_entry);
 914 #elif defined(HAVE_KRB5_KT_FREE_ENTRY)
 915         return krb5_kt_free_entry(context, kt_entry);
 916 #else
 917 #error UNKNOWN_KT_FREE_FUNCTION
 918 #endif
 919 }
 920
 921
 922 /* caller needs to free etype_s */
 923 krb5_error_code smb_krb5_enctype_to_string(krb5_context context,
 924                                            krb5_enctype enctype,
 925                                            char **etype_s)
 926 {
 927 #ifdef HAVE_KRB5_ENCTYPE_TO_STRING_WITH_KRB5_CONTEXT_ARG
 928         return krb5_enctype_to_string(context, enctype, etype_s); /* Heimdal */
 929 #elif defined(HAVE_KRB5_ENCTYPE_TO_STRING_WITH_SIZE_T_ARG)
 930         char buf[256];
 931         krb5_error_code ret = krb5_enctype_to_string(enctype, buf, 256); /* MIT */
 932         if (ret) {
 933                 return ret;
 934         }
 935         *etype_s = SMB_STRDUP(buf);
 936         if (!*etype_s) {
 937                 return ENOMEM;
 938         }
 939         return ret;
 940 #else
 941 #error UNKNOWN_KRB5_ENCTYPE_TO_STRING_FUNCTION
 942 #endif
 943 }
 944
 945 /**********************************************************************
 946  * Open a krb5 keytab with flags, handles readonly or readwrite access and
 947  * allows one to process non-default keytab names.
 948  * @param context krb5_context
 949  * @param keytab_name_req string
 950  * @param write_access bool if writable keytab is required
 951  * @param krb5_keytab pointer to krb5_keytab (close with krb5_kt_close())
 952  * @return krb5_error_code
 953 **********************************************************************/
 954
 955 /* This MAX_NAME_LEN is a constant defined in krb5.h */
 956 #ifndef MAX_KEYTAB_NAME_LEN
 957 #define MAX_KEYTAB_NAME_LEN 1100
 958 #endif
 959
 960 krb5_error_code smb_krb5_open_keytab_relative(krb5_context context,
 961                                               const char *keytab_name_req,
 962                                               bool write_access,
 963                                               krb5_keytab *keytab)
 964 {
 965         krb5_error_code ret = 0;
 966         TALLOC_CTX *mem_ctx;
 967         char keytab_string[MAX_KEYTAB_NAME_LEN];
 968         char *kt_str = NULL;
 969         bool found_valid_name = false;
 970         const char *pragma = "FILE";
 971         const char *tmp = NULL;
 972
 973         if (!write_access && !keytab_name_req) {
 974                 /* caller just wants to read the default keytab readonly, so be it */
 975                 return krb5_kt_default(context, keytab);
 976         }
 977
 978         mem_ctx = talloc_init("smb_krb5_open_keytab");
 979         if (!mem_ctx) {
 980                 return ENOMEM;
 981         }
 982
 983 #ifdef HAVE_WRFILE_KEYTAB
 984         if (write_access) {
 985                 pragma = "WRFILE";
 986         }
 987 #endif
 988
 989         if (keytab_name_req) {
 990
 991                 if (strlen(keytab_name_req) > MAX_KEYTAB_NAME_LEN) {
 992                         ret = KRB5_CONFIG_NOTENUFSPACE;
 993                         goto out;
 994                 }
 995
 996                 if ((strncmp(keytab_name_req, "WRFILE:/", 8) == 0) ||
 997                     (strncmp(keytab_name_req, "FILE:/", 6) == 0)) {
 998                         tmp = keytab_name_req;
 999                         goto resolve;
1000                 }
1001
1002                 tmp = talloc_asprintf(mem_ctx, "%s:%s", pragma, keytab_name_req);
1003                 if (!tmp) {
1004                         ret = ENOMEM;
1005                         goto out;
1006                 }
1007
1008                 goto resolve;
1009         }
1010
1011         /* we need to handle more complex keytab_strings, like:
1012          * "ANY:FILE:/etc/krb5.keytab,krb4:/etc/srvtab" */
1013
1014         ret = krb5_kt_default_name(context, &keytab_string[0], MAX_KEYTAB_NAME_LEN - 2);
1015         if (ret) {
1016                 goto out;
1017         }
1018
1019         DEBUG(10,("smb_krb5_open_keytab: krb5_kt_default_name returned %s\n", keytab_string));
1020
1021         tmp = talloc_strdup(mem_ctx, keytab_string);
1022         if (!tmp) {
1023                 ret = ENOMEM;
1024                 goto out;
1025         }
1026
1027         if (strncmp(tmp, "ANY:", 4) == 0) {
1028                 tmp += 4;
1029         }
1030
1031         memset(&keytab_string, '\0', sizeof(keytab_string));
1032
1033         while (next_token_talloc(mem_ctx, &tmp, &kt_str, ",")) {
1034                 if (strncmp(kt_str, "WRFILE:", 7) == 0) {
1035                         found_valid_name = true;
1036                         tmp = kt_str;
1037                         tmp += 7;
1038                 }
1039
1040                 if (strncmp(kt_str, "FILE:", 5) == 0) {
1041                         found_valid_name = true;
1042                         tmp = kt_str;
1043                         tmp += 5;
1044                 }
1045
1046                 if (tmp[0] == '/') {
1047                         /* Treat as a FILE: keytab definition. */
1048                         found_valid_name = true;
1049                 }
1050
1051                 if (found_valid_name) {
1052                         if (tmp[0] != '/') {
1053                                 ret = KRB5_KT_BADNAME;
1054                                 goto out;
1055                         }
1056
1057                         tmp = talloc_asprintf(mem_ctx, "%s:%s", pragma, tmp);
1058                         if (!tmp) {
1059                                 ret = ENOMEM;
1060                                 goto out;
1061                         }
1062                         break;
1063                 }
1064         }
1065
1066         if (!found_valid_name) {
1067                 ret = KRB5_KT_UNKNOWN_TYPE;
1068                 goto out;
1069         }
1070
1071  resolve:
1072         DEBUG(10,("smb_krb5_open_keytab: resolving: %s\n", tmp));
1073         ret = krb5_kt_resolve(context, tmp, keytab);
1074
1075  out:
1076         TALLOC_FREE(mem_ctx);
1077         return ret;
1078 }
1079
1080 krb5_error_code smb_krb5_open_keytab(krb5_context context,
1081                                      const char *keytab_name_req,
1082                                      bool write_access,
1083                                      krb5_keytab *keytab)
1084 {
1085         if (keytab_name_req != NULL) {
1086                 if (keytab_name_req[0] != '/') {
1087                         return KRB5_KT_BADNAME;
1088                 }
1089         }
1090
1091         return smb_krb5_open_keytab_relative(context,
1092                                              keytab_name_req,
1093                                              write_access,
1094                                              keytab);
1095 }
1096
1097 krb5_error_code smb_krb5_keytab_name(TALLOC_CTX *mem_ctx,
1098                                      krb5_context context,
1099                                      krb5_keytab keytab,
1100                                      const char **keytab_name)
1101 {
1102         char keytab_string[MAX_KEYTAB_NAME_LEN];
1103         krb5_error_code ret = 0;
1104
1105         ret = krb5_kt_get_name(context, keytab,
1106                                keytab_string, MAX_KEYTAB_NAME_LEN - 2);
1107         if (ret) {
1108                 return ret;
1109         }
1110
1111         *keytab_name = talloc_strdup(mem_ctx, keytab_string);
1112         if (!*keytab_name) {
1113                 return ENOMEM;
1114         }
1115
1116         return ret;
1117 }
1118
1119 /**
1120  * @brief Seek and delete old entries in a keytab based on the passed
1121  *        principal.
1122  *
1123  * @param[in]  context       The KRB5 context to use.
1124  *
1125  * @param[in]  keytab        The keytab to operate on.
1126  *
1127  * @param[in]  kvno          The kvnco to use.
1128  *
1129  * @param[in]  princ_s       The principal as a string to search for.
1130  *
1131  * @param[in]  princ         The principal as a krb5_principal to search for.
1132  *
1133  * @param[in]  flush         Weather to flush the complete keytab.
1134  *
1135  * @param[in]  keep_old_entries Keep the entry with the previous kvno.
1136  *
1137  * @retval 0 on Sucess
1138  *
1139  * @return An appropriate KRB5 error code.
1140  */
1141 krb5_error_code smb_krb5_kt_seek_and_delete_old_entries(krb5_context context,
1142                                                         krb5_keytab keytab,
1143                                                         krb5_kvno kvno,
1144                                                         krb5_enctype enctype,
1145                                                         const char *princ_s,
1146                                                         krb5_principal princ,
1147                                                         bool flush,
1148                                                         bool keep_old_entries)
1149 {
1150         krb5_error_code ret;
1151         krb5_kt_cursor cursor;
1152         krb5_kt_cursor zero_csr;
1153         krb5_keytab_entry kt_entry;
1154         krb5_keytab_entry zero_kt_entry;
1155         char *ktprinc = NULL;
1156         krb5_kvno old_kvno = kvno - 1;
1157         TALLOC_CTX *tmp_ctx;
1158
1159         ZERO_STRUCT(cursor);
1160         ZERO_STRUCT(zero_csr);
1161         ZERO_STRUCT(kt_entry);
1162         ZERO_STRUCT(zero_kt_entry);
1163
1164         ret = krb5_kt_start_seq_get(context, keytab, &cursor);
1165         if (ret == KRB5_KT_END || ret == ENOENT ) {
1166                 /* no entries */
1167                 return 0;
1168         }
1169
1170         tmp_ctx = talloc_new(NULL);
1171         if (tmp_ctx == NULL) {
1172                 return ENOMEM;
1173         }
1174
1175         DEBUG(3, (__location__ ": Will try to delete old keytab entries\n"));
1176         while (!krb5_kt_next_entry(context, keytab, &kt_entry, &cursor)) {
1177                 bool name_ok = false;
1178                 krb5_enctype kt_entry_enctype =
1179                         smb_krb5_kt_get_enctype_from_entry(&kt_entry);
1180
1181                 if (!flush && (princ_s != NULL)) {
1182                         ret = smb_krb5_unparse_name(tmp_ctx, context,
1183                                                     kt_entry.principal,
1184                                                     &ktprinc);
1185                         if (ret) {
1186                                 DEBUG(1, (__location__
1187                                           ": smb_krb5_unparse_name failed "
1188                                           "(%s)\n", error_message(ret)));
1189                                 goto out;
1190                         }
1191
1192 #ifdef HAVE_KRB5_KT_COMPARE
1193                         name_ok = krb5_kt_compare(context, &kt_entry,
1194                                                   princ, 0, 0);
1195 #else
1196                         name_ok = (strcmp(ktprinc, princ_s) == 0);
1197 #endif
1198
1199                         if (!name_ok) {
1200                                 DEBUG(10, (__location__ ": ignoring keytab "
1201                                            "entry principal %s, kvno = %d\n",
1202                                            ktprinc, kt_entry.vno));
1203
1204                                 /* Not a match,
1205                                  * just free this entry and continue. */
1206                                 ret = smb_krb5_kt_free_entry(context,
1207                                                              &kt_entry);
1208                                 ZERO_STRUCT(kt_entry);
1209                                 if (ret) {
1210                                         DEBUG(1, (__location__
1211                                                   ": smb_krb5_kt_free_entry "
1212                                                   "failed (%s)\n",
1213                                                   error_message(ret)));
1214                                         goto out;
1215                                 }
1216
1217                                 TALLOC_FREE(ktprinc);
1218                                 continue;
1219                         }
1220
1221                         TALLOC_FREE(ktprinc);
1222                 }
1223
1224                 /*------------------------------------------------------------
1225                  * Save the entries with kvno - 1. This is what microsoft does
1226                  * to allow people with existing sessions that have kvno - 1
1227                  * to still work. Otherwise, when the password for the machine
1228                  * changes, all kerberizied sessions will 'break' until either
1229                  * the client reboots or the client's session key expires and
1230                  * they get a new session ticket with the new kvno.
1231                  * Some keytab files only store the kvno in 8bits, limit
1232                  * the compare accordingly.
1233                  */
1234
1235                 if (!flush && ((kt_entry.vno & 0xff) == (old_kvno & 0xff))) {
1236                         DEBUG(5, (__location__ ": Saving previous (kvno %d) "
1237                                   "entry for principal: %s.\n",
1238                                   old_kvno, princ_s));
1239                         continue;
1240                 }
1241
1242                 if (keep_old_entries) {
1243                         DEBUG(5, (__location__ ": Saving old (kvno %d) "
1244                                   "entry for principal: %s.\n",
1245                                   kvno, princ_s));
1246                         continue;
1247                 }
1248
1249                 if (!flush &&
1250                     (kt_entry.vno == kvno) &&
1251                     (kt_entry_enctype != enctype))
1252                 {
1253                         DEBUG(5, (__location__ ": Saving entry with kvno [%d] "
1254                                   "enctype [%d] for principal: %s.\n",
1255                                   kvno, kt_entry_enctype, princ_s));
1256                         continue;
1257                 }
1258
1259                 DEBUG(5, (__location__ ": Found old entry for principal: %s "
1260                           "(kvno %d) - trying to remove it.\n",
1261                           princ_s, kt_entry.vno));
1262
1263                 ret = krb5_kt_end_seq_get(context, keytab, &cursor);
1264                 ZERO_STRUCT(cursor);
1265                 if (ret) {
1266                         DEBUG(1, (__location__ ": krb5_kt_end_seq_get() "
1267                                   "failed (%s)\n", error_message(ret)));
1268                         goto out;
1269                 }
1270                 ret = krb5_kt_remove_entry(context, keytab, &kt_entry);
1271                 if (ret) {
1272                         DEBUG(1, (__location__ ": krb5_kt_remove_entry() "
1273                                   "failed (%s)\n", error_message(ret)));
1274                         goto out;
1275                 }
1276
1277                 DEBUG(5, (__location__ ": removed old entry for principal: "
1278                           "%s (kvno %d).\n", princ_s, kt_entry.vno));
1279
1280                 ret = krb5_kt_start_seq_get(context, keytab, &cursor);
1281                 if (ret) {
1282                         DEBUG(1, (__location__ ": krb5_kt_start_seq() failed "
1283                                   "(%s)\n", error_message(ret)));
1284                         goto out;
1285                 }
1286                 ret = smb_krb5_kt_free_entry(context, &kt_entry);
1287                 ZERO_STRUCT(kt_entry);
1288                 if (ret) {
1289                         DEBUG(1, (__location__ ": krb5_kt_remove_entry() "
1290                                   "failed (%s)\n", error_message(ret)));
1291                         goto out;
1292                 }
1293         }
1294
1295 out:
1296         talloc_free(tmp_ctx);
1297         if (memcmp(&zero_kt_entry, &kt_entry, sizeof(krb5_keytab_entry))) {
1298                 smb_krb5_kt_free_entry(context, &kt_entry);
1299         }
1300         if (memcmp(&cursor, &zero_csr, sizeof(krb5_kt_cursor)) != 0) {
1301                 krb5_kt_end_seq_get(context, keytab, &cursor);
1302         }
1303         return ret;
1304 }
1305
1306 /**
1307  * @brief Add a keytab entry for the given principal
1308  *
1309  * @param[in]  context       The krb5 context to use.
1310  *
1311  * @param[in]  keytab        The keytab to add the entry to.
1312  *
1313  * @param[in]  kvno          The kvno to use.
1314  *
1315  * @param[in]  princ_s       The principal as a string.
1316  *
1317  * @param[in]  salt_principal The salt principal to salt the password with.
1318  *                            Only needed for keys which support salting.
1319  *                            If no salt is used set no_salt to false and
1320  *                            pass NULL here.
1321  *
1322  * @param[in]  enctype        The encryption type of the keytab entry.
1323  *
1324  * @param[in]  password       The password of the keytab entry.
1325  *
1326  * @param[in]  no_salt        If the password should not be salted. Normally
1327  *                            this is only set to false for encryption types
1328  *                            which do not support salting like RC4.
1329  *
1330  * @param[in]  keep_old_entries Wether to keep or delte old keytab entries.
1331  *
1332  * @retval 0 on Success
1333  *
1334  * @return A corresponding KRB5 error code.
1335  *
1336  * @see smb_krb5_open_keytab()
1337  */
1338 krb5_error_code smb_krb5_kt_add_entry(krb5_context context,
1339                                       krb5_keytab keytab,
1340                                       krb5_kvno kvno,
1341                                       const char *princ_s,
1342                                       const char *salt_principal,
1343                                       krb5_enctype enctype,
1344                                       krb5_data *password,
1345                                       bool no_salt,
1346                                       bool keep_old_entries)
1347 {
1348         krb5_error_code ret;
1349         krb5_keytab_entry kt_entry;
1350         krb5_principal princ = NULL;
1351         krb5_keyblock *keyp;
1352
1353         ZERO_STRUCT(kt_entry);
1354
1355         ret = smb_krb5_parse_name(context, princ_s, &princ);
1356         if (ret) {
1357                 DEBUG(1, (__location__ ": smb_krb5_parse_name(%s) "
1358                           "failed (%s)\n", princ_s, error_message(ret)));
1359                 goto out;
1360         }
1361
1362         /* Seek and delete old keytab entries */
1363         ret = smb_krb5_kt_seek_and_delete_old_entries(context,
1364                                                       keytab,
1365                                                       kvno,
1366                                                       enctype,
1367                                                       princ_s,
1368                                                       princ,
1369                                                       false,
1370                                                       keep_old_entries);
1371         if (ret) {
1372                 goto out;
1373         }
1374
1375         /* If we get here, we have deleted all the old entries with kvno's
1376          * not equal to the current kvno-1. */
1377
1378         keyp = KRB5_KT_KEY(&kt_entry);
1379
1380         if (no_salt) {
1381                 KRB5_KEY_DATA(keyp) = (KRB5_KEY_DATA_CAST *)SMB_MALLOC(password->length);
1382                 if (KRB5_KEY_DATA(keyp) == NULL) {
1383                         ret = ENOMEM;
1384                         goto out;
1385                 }
1386                 memcpy(KRB5_KEY_DATA(keyp), password->data, password->length);
1387                 KRB5_KEY_LENGTH(keyp) = password->length;
1388                 KRB5_KEY_TYPE(keyp) = enctype;
1389         } else {
1390                 krb5_principal salt_princ = NULL;
1391
1392                 /* Now add keytab entries for all encryption types */
1393                 ret = smb_krb5_parse_name(context, salt_principal, &salt_princ);
1394                 if (ret) {
1395                         DBG_WARNING("krb5_parse_name(%s) failed (%s)\n",
1396                                     salt_principal, error_message(ret));
1397                         goto out;
1398                 }
1399
1400                 ret = smb_krb5_create_key_from_string(context,
1401                                                       salt_princ,
1402                                                       NULL,
1403                                                       password,
1404                                                       enctype,
1405                                                       keyp);
1406                 krb5_free_principal(context, salt_princ);
1407                 if (ret != 0) {
1408                         goto out;
1409                 }
1410         }
1411
1412         kt_entry.principal = princ;
1413         kt_entry.vno       = kvno;
1414
1415         DEBUG(3, (__location__ ": adding keytab entry for (%s) with "
1416                   "encryption type (%d) and version (%d)\n",
1417                   princ_s, enctype, kt_entry.vno));
1418         ret = krb5_kt_add_entry(context, keytab, &kt_entry);
1419         krb5_free_keyblock_contents(context, keyp);
1420         ZERO_STRUCT(kt_entry);
1421         if (ret) {
1422                 DEBUG(1, (__location__ ": adding entry to keytab "
1423                           "failed (%s)\n", error_message(ret)));
1424                 goto out;
1425         }
1426
1427 out:
1428         if (princ) {
1429                 krb5_free_principal(context, princ);
1430         }
1431
1432         return ret;
1433 }
1434
1435 #if defined(HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE) && \
1436     defined(HAVE_KRB5_GET_CREDS_OPT_ALLOC) && \
1437     defined(HAVE_KRB5_GET_CREDS)
1438 static krb5_error_code smb_krb5_get_credentials_for_user_opt(krb5_context context,
1439                                                              krb5_ccache ccache,
1440                                                              krb5_principal me,
1441                                                              krb5_principal server,
1442                                                              krb5_principal impersonate_princ,
1443                                                              krb5_creds **out_creds)
1444 {
1445         krb5_error_code ret;
1446         krb5_get_creds_opt opt;
1447
1448         ret = krb5_get_creds_opt_alloc(context, &opt);
1449         if (ret) {
1450                 goto done;
1451         }
1452         krb5_get_creds_opt_add_options(context, opt, KRB5_GC_FORWARDABLE);
1453
1454         if (impersonate_princ) {
1455                 ret = krb5_get_creds_opt_set_impersonate(context, opt,
1456                                                          impersonate_princ);
1457                 if (ret) {
1458                         goto done;
1459                 }
1460         }
1461
1462         ret = krb5_get_creds(context, opt, ccache, server, out_creds);
1463         if (ret) {
1464                 goto done;
1465         }
1466
1467  done:
1468         if (opt) {
1469                 krb5_get_creds_opt_free(context, opt);
1470         }
1471         return ret;
1472 }
1473 #endif /* HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE */
1474
1475 #ifdef HAVE_KRB5_GET_CREDENTIALS_FOR_USER
1476
1477 #if !HAVE_DECL_KRB5_GET_CREDENTIALS_FOR_USER
1478 krb5_error_code KRB5_CALLCONV
1479 krb5_get_credentials_for_user(krb5_context context, krb5_flags options,
1480                               krb5_ccache ccache, krb5_creds *in_creds,
1481                               krb5_data *subject_cert,
1482                               krb5_creds **out_creds);
1483 #endif /* !HAVE_DECL_KRB5_GET_CREDENTIALS_FOR_USER */
1484
1485 static krb5_error_code smb_krb5_get_credentials_for_user(krb5_context context,
1486                                                          krb5_ccache ccache,
1487                                                          krb5_principal me,
1488                                                          krb5_principal server,
1489                                                          krb5_principal impersonate_princ,
1490                                                          krb5_creds **out_creds)
1491 {
1492         krb5_error_code ret;
1493         krb5_creds in_creds;
1494
1495         ZERO_STRUCT(in_creds);
1496
1497         if (impersonate_princ) {
1498
1499                 in_creds.server = me;
1500                 in_creds.client = impersonate_princ;
1501
1502                 ret = krb5_get_credentials_for_user(context,
1503                                                     0, /* krb5_flags options */
1504                                                     ccache,
1505                                                     &in_creds,
1506                                                     NULL, /* krb5_data *subject_cert */
1507                                                     out_creds);
1508         } else {
1509                 in_creds.client = me;
1510                 in_creds.server = server;
1511
1512                 ret = krb5_get_credentials(context, 0, ccache,
1513                                            &in_creds, out_creds);
1514         }
1515
1516         return ret;
1517 }
1518 #endif /* HAVE_KRB5_GET_CREDENTIALS_FOR_USER */
1519
1520 /*
1521  * smb_krb5_get_credentials
1522  *
1523  * @brief Get krb5 credentials for a server
1524  *
1525  * @param[in] context           An initialized krb5_context
1526  * @param[in] ccache            An initialized krb5_ccache
1527  * @param[in] me                The krb5_principal of the caller
1528  * @param[in] server            The krb5_principal of the requested service
1529  * @param[in] impersonate_princ The krb5_principal of a user to impersonate as (optional)
1530  * @param[out] out_creds        The returned krb5_creds structure
1531  * @return krb5_error_code
1532  *
1533  */
1534 krb5_error_code smb_krb5_get_credentials(krb5_context context,
1535                                          krb5_ccache ccache,
1536                                          krb5_principal me,
1537                                          krb5_principal server,
1538                                          krb5_principal impersonate_princ,
1539                                          krb5_creds **out_creds)
1540 {
1541         krb5_error_code ret;
1542         krb5_creds *creds = NULL;
1543
1544         if (out_creds != NULL) {
1545                 *out_creds = NULL;
1546         }
1547
1548         if (impersonate_princ) {
1549 #ifdef HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE /* Heimdal */
1550                 ret = smb_krb5_get_credentials_for_user_opt(context, ccache, me, server, impersonate_princ, &creds);
1551 #elif defined(HAVE_KRB5_GET_CREDENTIALS_FOR_USER) /* MIT */
1552                 ret = smb_krb5_get_credentials_for_user(context, ccache, me, server, impersonate_princ, &creds);
1553 #else
1554                 ret = ENOTSUP;
1555 #endif
1556         } else {
1557                 krb5_creds in_creds;
1558
1559                 ZERO_STRUCT(in_creds);
1560
1561                 in_creds.client = me;
1562                 in_creds.server = server;
1563
1564                 ret = krb5_get_credentials(context, 0, ccache,
1565                                            &in_creds, &creds);
1566         }
1567         if (ret) {
1568                 goto done;
1569         }
1570
1571         if (out_creds) {
1572                 *out_creds = creds;
1573         }
1574
1575  done:
1576         if (creds && ret) {
1577                 krb5_free_creds(context, creds);
1578         }
1579
1580         return ret;
1581 }
1582
1583 krb5_error_code smb_krb5_keyblock_init_contents(krb5_context context,
1584                                                 krb5_enctype enctype,
1585                                                 const void *data,
1586                                                 size_t length,
1587                                                 krb5_keyblock *key)
1588 {
1589 #if defined(HAVE_KRB5_KEYBLOCK_INIT)
1590         return krb5_keyblock_init(context, enctype, data, length, key);
1591 #else
1592         memset(key, 0, sizeof(krb5_keyblock));
1593         KRB5_KEY_DATA(key) = SMB_MALLOC(length);
1594         if (NULL == KRB5_KEY_DATA(key)) {
1595                 return ENOMEM;
1596         }
1597         memcpy(KRB5_KEY_DATA(key), data, length);
1598         KRB5_KEY_LENGTH(key) = length;
1599         KRB5_KEY_TYPE(key) = enctype;
1600         return 0;
1601 #endif
1602 }
1603
1604 /*
1605   simulate a kinit, putting the tgt in the given credentials cache.
1606   Orignally by remus@snapserver.com
1607
1608   This version is built to use a keyblock, rather than needing the
1609   original password.
1610
1611   The impersonate_principal is the principal if NULL, or the principal
1612   to impersonate
1613
1614   The target_service defaults to the krbtgt if NULL, but could be
1615    kpasswd/realm or the local service (if we are doing s4u2self)
1616 */
1617 krb5_error_code kerberos_kinit_keyblock_cc(krb5_context ctx, krb5_ccache cc,
1618                                            krb5_principal principal,
1619                                            krb5_keyblock *keyblock,
1620                                            const char *target_service,
1621                                            krb5_get_init_creds_opt *krb_options,
1622                                            time_t *expire_time,
1623                                            time_t *kdc_time)
1624 {
1625         krb5_error_code code = 0;
1626         krb5_creds my_creds;
1627
1628 #if defined(HAVE_KRB5_GET_INIT_CREDS_KEYBLOCK)
1629         code = krb5_get_init_creds_keyblock(ctx, &my_creds, principal,
1630                                             keyblock, 0, target_service,
1631                                             krb_options);
1632 #elif defined(HAVE_KRB5_GET_INIT_CREDS_KEYTAB)
1633 {
1634 #define SMB_CREDS_KEYTAB "MEMORY:tmp_smb_creds_XXXXXX"
1635         char tmp_name[sizeof(SMB_CREDS_KEYTAB)];
1636         krb5_keytab_entry entry;
1637         krb5_keytab keytab;
1638         mode_t mask;
1639
1640         memset(&entry, 0, sizeof(entry));
1641         entry.principal = principal;
1642         *(KRB5_KT_KEY(&entry)) = *keyblock;
1643
1644         memcpy(tmp_name, SMB_CREDS_KEYTAB, sizeof(SMB_CREDS_KEYTAB));
1645         mask = umask(S_IRWXO | S_IRWXG);
1646         mktemp(tmp_name);
1647         umask(mask);
1648         if (tmp_name[0] == 0) {
1649                 return KRB5_KT_BADNAME;
1650         }
1651         code = krb5_kt_resolve(ctx, tmp_name, &keytab);
1652         if (code) {
1653                 return code;
1654         }
1655
1656         code = krb5_kt_add_entry(ctx, keytab, &entry);
1657         if (code) {
1658                 (void)krb5_kt_close(ctx, keytab);
1659                 goto done;
1660         }
1661
1662         code = krb5_get_init_creds_keytab(ctx, &my_creds, principal,
1663                                           keytab, 0, target_service,
1664                                           krb_options);
1665         (void)krb5_kt_close(ctx, keytab);
1666 }
1667 #else
1668 #error krb5_get_init_creds_keyblock not available!
1669 #endif
1670         if (code) {
1671                 return code;
1672         }
1673
1674 #ifndef SAMBA4_USES_HEIMDAL /* MIT */
1675         /*
1676          * We need to store the principal as returned from the KDC to the
1677          * credentials cache. If we don't do that the KRB5 library is not
1678          * able to find the tickets it is looking for
1679          */
1680         principal = my_creds.client;
1681 #endif
1682         code = krb5_cc_initialize(ctx, cc, principal);
1683         if (code) {
1684                 goto done;
1685         }
1686
1687         code = krb5_cc_store_cred(ctx, cc, &my_creds);
1688         if (code) {
1689                 goto done;
1690         }
1691
1692         if (expire_time) {
1693                 *expire_time = (time_t) my_creds.times.endtime;
1694         }
1695
1696         if (kdc_time) {
1697                 *kdc_time = (time_t) my_creds.times.starttime;
1698         }
1699
1700         code = 0;
1701 done:
1702         krb5_free_cred_contents(ctx, &my_creds);
1703         return code;
1704 }
1705
1706 krb5_error_code kerberos_kinit_password_cc(krb5_context ctx, krb5_ccache cc,
1707                                            krb5_principal principal,
1708                                            const char *password,
1709                                            const char *target_service,
1710                                            krb5_get_init_creds_opt *krb_options,
1711                                            time_t *expire_time,
1712                                            time_t *kdc_time)
1713 {
1714         krb5_error_code code = 0;
1715         krb5_creds my_creds;
1716
1717         code = krb5_get_init_creds_password(ctx, &my_creds, principal,
1718                                             password, NULL, NULL, 0,
1719                                             target_service, krb_options);
1720         if (code) {
1721                 return code;
1722         }
1723
1724 #ifndef SAMBA4_USES_HEIMDAL /* MIT */
1725         /*
1726          * We need to store the principal as returned from the KDC to the
1727          * credentials cache. If we don't do that the KRB5 library is not
1728          * able to find the tickets it is looking for
1729          */
1730         principal = my_creds.client;
1731 #endif
1732         code = krb5_cc_initialize(ctx, cc, principal);
1733         if (code) {
1734                 goto done;
1735         }
1736
1737         code = krb5_cc_store_cred(ctx, cc, &my_creds);
1738         if (code) {
1739                 goto done;
1740         }
1741
1742         if (expire_time) {
1743                 *expire_time = (time_t) my_creds.times.endtime;
1744         }
1745
1746         if (kdc_time) {
1747                 *kdc_time = (time_t) my_creds.times.starttime;
1748         }
1749
1750         code = 0;
1751 done:
1752         krb5_free_cred_contents(ctx, &my_creds);
1753         return code;
1754 }
1755
1756 #ifdef SAMBA4_USES_HEIMDAL
1757 /*
1758   simulate a kinit, putting the tgt in the given credentials cache.
1759   Orignally by remus@snapserver.com
1760
1761   The impersonate_principal is the principal
1762
1763   The self_service, should be the local service (for S4U2Self if
1764   impersonate_principal is given).
1765
1766   The target_service defaults to the krbtgt if NULL, but could be
1767   kpasswd/realm or a remote service (for S4U2Proxy)
1768
1769 */
1770 krb5_error_code kerberos_kinit_s4u2_cc(krb5_context ctx,
1771                                         krb5_ccache store_cc,
1772                                         krb5_principal init_principal,
1773                                         const char *init_password,
1774                                         krb5_principal impersonate_principal,
1775                                         const char *self_service,
1776                                         const char *target_service,
1777                                         krb5_get_init_creds_opt *krb_options,
1778                                         time_t *expire_time,
1779                                         time_t *kdc_time)
1780 {
1781         krb5_error_code code = 0;
1782         krb5_get_creds_opt options;
1783         krb5_principal store_principal;
1784         krb5_creds store_creds;
1785         krb5_creds *s4u2self_creds;
1786         Ticket s4u2self_ticket;
1787         size_t s4u2self_ticketlen;
1788         krb5_creds *s4u2proxy_creds;
1789         krb5_principal self_princ;
1790         bool s4u2proxy;
1791         krb5_principal target_princ;
1792         krb5_ccache tmp_cc;
1793         const char *self_realm;
1794         krb5_principal blacklist_principal = NULL;
1795         krb5_principal whitelist_principal = NULL;
1796
1797         code = krb5_get_init_creds_password(ctx, &store_creds,
1798                                             init_principal,
1799                                             init_password,
1800                                             NULL, NULL,
1801                                             0,
1802                                             NULL,
1803                                             krb_options);
1804         if (code != 0) {
1805                 return code;
1806         }
1807
1808         store_principal = init_principal;
1809
1810         /*
1811          * We are trying S4U2Self now:
1812          *
1813          * As we do not want to expose our TGT in the
1814          * krb5_ccache, which is also holds the impersonated creds.
1815          *
1816          * Some low level krb5/gssapi function might use the TGT
1817          * identity and let the client act as our machine account.
1818          *
1819          * We need to avoid that and use a temporary krb5_ccache
1820          * in order to pass our TGT to the krb5_get_creds() function.
1821          */
1822         code = krb5_cc_new_unique(ctx, NULL, NULL, &tmp_cc);
1823         if (code != 0) {
1824                 krb5_free_cred_contents(ctx, &store_creds);
1825                 return code;
1826         }
1827
1828         code = krb5_cc_initialize(ctx, tmp_cc, store_creds.client);
1829         if (code != 0) {
1830                 krb5_cc_destroy(ctx, tmp_cc);
1831                 krb5_free_cred_contents(ctx, &store_creds);
1832                 return code;
1833         }
1834
1835         code = krb5_cc_store_cred(ctx, tmp_cc, &store_creds);
1836         if (code != 0) {
1837                 krb5_free_cred_contents(ctx, &store_creds);
1838                 krb5_cc_destroy(ctx, tmp_cc);
1839                 return code;
1840         }
1841
1842         /*
1843          * we need to remember the client principal of our
1844          * TGT and make sure the KDC does not return this
1845          * in the impersonated tickets. This can happen
1846          * if the KDC does not support S4U2Self and S4U2Proxy.
1847          */
1848         blacklist_principal = store_creds.client;
1849         store_creds.client = NULL;
1850         krb5_free_cred_contents(ctx, &store_creds);
1851
1852         /*
1853          * Check if we also need S4U2Proxy or if S4U2Self is
1854          * enough in order to get a ticket for the target.
1855          */
1856         if (target_service == NULL) {
1857                 s4u2proxy = false;
1858         } else if (strcmp(target_service, self_service) == 0) {
1859                 s4u2proxy = false;
1860         } else {
1861                 s4u2proxy = true;
1862         }
1863
1864         /*
1865          * For S4U2Self we need our own service principal,
1866          * which belongs to our own realm (available on
1867          * our client principal).
1868          */
1869         self_realm = krb5_principal_get_realm(ctx, init_principal);
1870
1871         code = krb5_parse_name(ctx, self_service, &self_princ);
1872         if (code != 0) {
1873                 krb5_free_principal(ctx, blacklist_principal);
1874                 krb5_cc_destroy(ctx, tmp_cc);
1875                 return code;
1876         }
1877
1878         code = krb5_principal_set_realm(ctx, self_princ, self_realm);
1879         if (code != 0) {
1880                 krb5_free_principal(ctx, blacklist_principal);
1881                 krb5_free_principal(ctx, self_princ);
1882                 krb5_cc_destroy(ctx, tmp_cc);
1883                 return code;
1884         }
1885
1886         code = krb5_get_creds_opt_alloc(ctx, &options);
1887         if (code != 0) {
1888                 krb5_free_principal(ctx, blacklist_principal);
1889                 krb5_free_principal(ctx, self_princ);
1890                 krb5_cc_destroy(ctx, tmp_cc);
1891                 return code;
1892         }
1893
1894         if (s4u2proxy) {
1895                 /*
1896                  * If we want S4U2Proxy, we need the forwardable flag
1897                  * on the S4U2Self ticket.
1898                  */
1899                 krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_FORWARDABLE);
1900         }
1901
1902         code = krb5_get_creds_opt_set_impersonate(ctx, options,
1903                                                   impersonate_principal);
1904         if (code != 0) {
1905                 krb5_get_creds_opt_free(ctx, options);
1906                 krb5_free_principal(ctx, blacklist_principal);
1907                 krb5_free_principal(ctx, self_princ);
1908                 krb5_cc_destroy(ctx, tmp_cc);
1909                 return code;
1910         }
1911
1912         code = krb5_get_creds(ctx, options, tmp_cc,
1913                               self_princ, &s4u2self_creds);
1914         krb5_get_creds_opt_free(ctx, options);
1915         krb5_free_principal(ctx, self_princ);
1916         if (code != 0) {
1917                 krb5_free_principal(ctx, blacklist_principal);
1918                 krb5_cc_destroy(ctx, tmp_cc);
1919                 return code;
1920         }
1921
1922         if (!s4u2proxy) {
1923                 krb5_cc_destroy(ctx, tmp_cc);
1924
1925                 /*
1926                  * Now make sure we store the impersonated principal
1927                  * and creds instead of the TGT related stuff
1928                  * in the krb5_ccache of the caller.
1929                  */
1930                 code = krb5_copy_creds_contents(ctx, s4u2self_creds,
1931                                                 &store_creds);
1932                 krb5_free_creds(ctx, s4u2self_creds);
1933                 if (code != 0) {
1934                         return code;
1935                 }
1936
1937                 /*
1938                  * It's important to store the principal the KDC
1939                  * returned, as otherwise the caller would not find
1940                  * the S4U2Self ticket in the krb5_ccache lookup.
1941                  */
1942                 store_principal = store_creds.client;
1943                 goto store;
1944         }
1945
1946         /*
1947          * We are trying S4U2Proxy:
1948          *
1949          * We need the ticket from the S4U2Self step
1950          * and our TGT in order to get the delegated ticket.
1951          */
1952         code = decode_Ticket((const uint8_t *)s4u2self_creds->ticket.data,
1953                              s4u2self_creds->ticket.length,
1954                              &s4u2self_ticket,
1955                              &s4u2self_ticketlen);
1956         if (code != 0) {
1957                 krb5_free_creds(ctx, s4u2self_creds);
1958                 krb5_free_principal(ctx, blacklist_principal);
1959                 krb5_cc_destroy(ctx, tmp_cc);
1960                 return code;
1961         }
1962
1963         /*
1964          * we need to remember the client principal of the
1965          * S4U2Self stage and as it needs to match the one we
1966          * will get for the S4U2Proxy stage. We need this
1967          * in order to detect KDCs which does not support S4U2Proxy.
1968          */
1969         whitelist_principal = s4u2self_creds->client;
1970         s4u2self_creds->client = NULL;
1971         krb5_free_creds(ctx, s4u2self_creds);
1972
1973         /*
1974          * For S4U2Proxy we also got a target service principal,
1975          * which also belongs to our own realm (available on
1976          * our client principal).
1977          */
1978         code = krb5_parse_name(ctx, target_service, &target_princ);
1979         if (code != 0) {
1980                 free_Ticket(&s4u2self_ticket);
1981                 krb5_free_principal(ctx, whitelist_principal);
1982                 krb5_free_principal(ctx, blacklist_principal);
1983                 krb5_cc_destroy(ctx, tmp_cc);
1984                 return code;
1985         }
1986
1987         code = krb5_principal_set_realm(ctx, target_princ, self_realm);
1988         if (code != 0) {
1989                 free_Ticket(&s4u2self_ticket);
1990                 krb5_free_principal(ctx, target_princ);
1991                 krb5_free_principal(ctx, whitelist_principal);
1992                 krb5_free_principal(ctx, blacklist_principal);
1993                 krb5_cc_destroy(ctx, tmp_cc);
1994                 return code;
1995         }
1996
1997         code = krb5_get_creds_opt_alloc(ctx, &options);
1998         if (code != 0) {
1999                 free_Ticket(&s4u2self_ticket);
2000                 krb5_free_principal(ctx, target_princ);
2001                 krb5_free_principal(ctx, whitelist_principal);
2002                 krb5_free_principal(ctx, blacklist_principal);
2003                 krb5_cc_destroy(ctx, tmp_cc);
2004                 return code;
2005         }
2006
2007         krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_FORWARDABLE);
2008         krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_CONSTRAINED_DELEGATION);
2009
2010         code = krb5_get_creds_opt_set_ticket(ctx, options, &s4u2self_ticket);
2011         free_Ticket(&s4u2self_ticket);
2012         if (code != 0) {
2013                 krb5_get_creds_opt_free(ctx, options);
2014                 krb5_free_principal(ctx, target_princ);
2015                 krb5_free_principal(ctx, whitelist_principal);
2016                 krb5_free_principal(ctx, blacklist_principal);
2017                 krb5_cc_destroy(ctx, tmp_cc);
2018                 return code;
2019         }
2020
2021         code = krb5_get_creds(ctx, options, tmp_cc,
2022                               target_princ, &s4u2proxy_creds);
2023         krb5_get_creds_opt_free(ctx, options);
2024         krb5_free_principal(ctx, target_princ);
2025         krb5_cc_destroy(ctx, tmp_cc);
2026         if (code != 0) {
2027                 krb5_free_principal(ctx, whitelist_principal);
2028                 krb5_free_principal(ctx, blacklist_principal);
2029                 return code;
2030         }
2031
2032         /*
2033          * Now make sure we store the impersonated principal
2034          * and creds instead of the TGT related stuff
2035          * in the krb5_ccache of the caller.
2036          */
2037         code = krb5_copy_creds_contents(ctx, s4u2proxy_creds,
2038                                         &store_creds);
2039         krb5_free_creds(ctx, s4u2proxy_creds);
2040         if (code != 0) {
2041                 krb5_free_principal(ctx, whitelist_principal);
2042                 krb5_free_principal(ctx, blacklist_principal);
2043                 return code;
2044         }
2045
2046         /*
2047          * It's important to store the principal the KDC
2048          * returned, as otherwise the caller would not find
2049          * the S4U2Self ticket in the krb5_ccache lookup.
2050          */
2051         store_principal = store_creds.client;
2052
2053  store:
2054         if (blacklist_principal &&
2055             krb5_principal_compare(ctx, store_creds.client, blacklist_principal)) {
2056                 char *sp = NULL;
2057                 char *ip = NULL;
2058
2059                 code = krb5_unparse_name(ctx, blacklist_principal, &sp);
2060                 if (code != 0) {
2061                         sp = NULL;
2062                 }
2063                 code = krb5_unparse_name(ctx, impersonate_principal, &ip);
2064                 if (code != 0) {
2065                         ip = NULL;
2066                 }
2067                 DEBUG(1, ("kerberos_kinit_password_cc: "
2068                           "KDC returned self principal[%s] while impersonating [%s]\n",
2069                           sp?sp:"<no memory>",
2070                           ip?ip:"<no memory>"));
2071
2072                 SAFE_FREE(sp);
2073                 SAFE_FREE(ip);
2074
2075                 krb5_free_principal(ctx, whitelist_principal);
2076                 krb5_free_principal(ctx, blacklist_principal);
2077                 krb5_free_cred_contents(ctx, &store_creds);
2078                 return KRB5_FWD_BAD_PRINCIPAL;
2079         }
2080         if (blacklist_principal) {
2081                 krb5_free_principal(ctx, blacklist_principal);
2082         }
2083
2084         if (whitelist_principal &&
2085             !krb5_principal_compare(ctx, store_creds.client, whitelist_principal)) {
2086                 char *sp = NULL;
2087                 char *ep = NULL;
2088
2089                 code = krb5_unparse_name(ctx, store_creds.client, &sp);
2090                 if (code != 0) {
2091                         sp = NULL;
2092                 }
2093                 code = krb5_unparse_name(ctx, whitelist_principal, &ep);
2094                 if (code != 0) {
2095                         ep = NULL;
2096                 }
2097                 DEBUG(1, ("kerberos_kinit_password_cc: "
2098                           "KDC returned wrong principal[%s] we expected [%s]\n",
2099                           sp?sp:"<no memory>",
2100                           ep?ep:"<no memory>"));
2101
2102                 SAFE_FREE(sp);
2103                 SAFE_FREE(ep);
2104
2105                 krb5_free_principal(ctx, whitelist_principal);
2106                 krb5_free_cred_contents(ctx, &store_creds);
2107                 return KRB5_FWD_BAD_PRINCIPAL;
2108         }
2109         if (whitelist_principal) {
2110                 krb5_free_principal(ctx, whitelist_principal);
2111         }
2112
2113         code = krb5_cc_initialize(ctx, store_cc, store_principal);
2114         if (code != 0) {
2115                 krb5_free_cred_contents(ctx, &store_creds);
2116                 return code;
2117         }
2118
2119         code = krb5_cc_store_cred(ctx, store_cc, &store_creds);
2120         if (code != 0) {
2121                 krb5_free_cred_contents(ctx, &store_creds);
2122                 return code;
2123         }
2124
2125         if (expire_time) {
2126                 *expire_time = (time_t) store_creds.times.endtime;
2127         }
2128
2129         if (kdc_time) {
2130                 *kdc_time = (time_t) store_creds.times.starttime;
2131         }
2132
2133         krb5_free_cred_contents(ctx, &store_creds);
2134
2135         return 0;
2136 }
2137 #endif
2138
2139 #if !defined(HAVE_KRB5_MAKE_PRINCIPAL) && defined(HAVE_KRB5_BUILD_PRINCIPAL_ALLOC_VA)
2140 krb5_error_code smb_krb5_make_principal(krb5_context context,
2141                                         krb5_principal *principal,
2142                                         const char *_realm, ...)
2143 {
2144         krb5_error_code code;
2145         bool free_realm;
2146         char *realm;
2147         va_list ap;
2148
2149         if (_realm) {
2150                 realm = discard_const_p(char, _realm);
2151                 free_realm = false;
2152         } else {
2153                 code = krb5_get_default_realm(context, &realm);
2154                 if (code) {
2155                         return code;
2156                 }
2157                 free_realm = true;
2158         }
2159
2160         va_start(ap, _realm);
2161         code = krb5_build_principal_alloc_va(context, principal,
2162                                              strlen(realm), realm,
2163                                              ap);
2164         va_end(ap);
2165
2166         if (free_realm) {
2167                 krb5_free_default_realm(context, realm);
2168         }
2169
2170         return code;
2171 }
2172 #endif
2173
2174 #if !defined(HAVE_KRB5_CC_GET_LIFETIME) && defined(HAVE_KRB5_CC_RETRIEVE_CRED)
2175 /**
2176  * @brief Get the lifetime of the initial ticket in the cache.
2177  *
2178  * @param[in]  context  The kerberos context.
2179  *
2180  * @param[in]  id       The credential cache to get the ticket lifetime.
2181  *
2182  * @param[out] t        A pointer to a time value to store the lifetime.
2183  *
2184  * @return              0 on success, a krb5_error_code on error.
2185  */
2186 krb5_error_code smb_krb5_cc_get_lifetime(krb5_context context,
2187                                          krb5_ccache id,
2188                                          time_t *t)
2189 {
2190         krb5_cc_cursor cursor;
2191         krb5_error_code kerr;
2192         krb5_creds cred;
2193         krb5_timestamp now;
2194
2195         *t = 0;
2196
2197         kerr = krb5_timeofday(context, &now);
2198         if (kerr) {
2199                 return kerr;
2200         }
2201
2202         kerr = krb5_cc_start_seq_get(context, id, &cursor);
2203         if (kerr) {
2204                 return kerr;
2205         }
2206
2207         while ((kerr = krb5_cc_next_cred(context, id, &cursor, &cred)) == 0) {
2208 #ifndef HAVE_FLAGS_IN_KRB5_CREDS
2209                 if (cred.ticket_flags & TKT_FLG_INITIAL) {
2210 #else
2211                 if (cred.flags.b.initial) {
2212 #endif
2213                         if (now < cred.times.endtime) {
2214                                 *t = (time_t) (cred.times.endtime - now);
2215                         }
2216                         krb5_free_cred_contents(context, &cred);
2217                         break;
2218                 }
2219                 krb5_free_cred_contents(context, &cred);
2220         }
2221
2222         krb5_cc_end_seq_get(context, id, &cursor);
2223
2224         return kerr;
2225 }
2226 #endif /* HAVE_KRB5_CC_GET_LIFETIME */
2227
2228 #if !defined(HAVE_KRB5_FREE_CHECKSUM_CONTENTS) && defined(HAVE_FREE_CHECKSUM)
2229 void smb_krb5_free_checksum_contents(krb5_context ctx, krb5_checksum *cksum)
2230 {
2231         free_Checksum(cksum);
2232 }
2233 #endif
2234
2235 krb5_error_code smb_krb5_make_pac_checksum(TALLOC_CTX *mem_ctx,
2236                                            DATA_BLOB *pac_data,
2237                                            krb5_context context,
2238                                            const krb5_keyblock *keyblock,
2239                                            uint32_t *sig_type,
2240                                            DATA_BLOB *sig_blob)
2241 {
2242         krb5_error_code ret;
2243         krb5_checksum cksum;
2244 #if defined(HAVE_KRB5_CRYPTO_INIT) && defined(HAVE_KRB5_CREATE_CHECKSUM)
2245         krb5_crypto crypto;
2246
2247
2248         ret = krb5_crypto_init(context,
2249                                keyblock,
2250                                0,
2251                                &crypto);
2252         if (ret) {
2253                 DEBUG(0,("krb5_crypto_init() failed: %s\n",
2254                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2255                 return ret;
2256         }
2257         ret = krb5_create_checksum(context,
2258                                    crypto,
2259                                    KRB5_KU_OTHER_CKSUM,
2260                                    0,
2261                                    pac_data->data,
2262                                    pac_data->length,
2263                                    &cksum);
2264         if (ret) {
2265                 DEBUG(2, ("PAC Verification failed: %s\n",
2266                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2267         }
2268
2269         krb5_crypto_destroy(context, crypto);
2270
2271         if (ret) {
2272                 return ret;
2273         }
2274
2275         *sig_type = cksum.cksumtype;
2276         *sig_blob = data_blob_talloc(mem_ctx,
2277                                         cksum.checksum.data,
2278                                         cksum.checksum.length);
2279 #elif defined(HAVE_KRB5_C_MAKE_CHECKSUM)
2280         krb5_data input;
2281
2282         input.data = (char *)pac_data->data;
2283         input.length = pac_data->length;
2284
2285         ret = krb5_c_make_checksum(context,
2286                                    0,
2287                                    keyblock,
2288                                    KRB5_KEYUSAGE_APP_DATA_CKSUM,
2289                                    &input,
2290                                    &cksum);
2291         if (ret) {
2292                 DEBUG(2, ("PAC Verification failed: %s\n",
2293                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2294                 return ret;
2295         }
2296
2297         *sig_type = cksum.checksum_type;
2298         *sig_blob = data_blob_talloc(mem_ctx,
2299                                         cksum.contents,
2300                                         cksum.length);
2301
2302 #else
2303 #error krb5_create_checksum or krb5_c_make_checksum not available
2304 #endif /* HAVE_KRB5_C_MAKE_CHECKSUM */
2305         smb_krb5_free_checksum_contents(context, &cksum);
2306
2307         return 0;
2308 }
2309
2310
2311 /*
2312  * smb_krb5_principal_get_realm
2313  *
2314  * @brief Get realm of a principal
2315  *
2316  * @param[in] context           The krb5_context
2317  * @param[in] principal         The principal
2318  * @return pointer to the realm
2319  *
2320  * Caller must free if the return value is not NULL.
2321  *
2322  */
2323
2324 char *smb_krb5_principal_get_realm(krb5_context context,
2325                                    krb5_const_principal principal)
2326 {
2327 #ifdef HAVE_KRB5_PRINCIPAL_GET_REALM /* Heimdal */
2328         return strdup(discard_const_p(char, krb5_principal_get_realm(context, principal)));
2329 #elif defined(krb5_princ_realm) /* MIT */
2330         krb5_data *realm;
2331         realm = discard_const_p(krb5_data,
2332                                 krb5_princ_realm(context, principal));
2333         return strndup(realm->data, realm->length);
2334 #else
2335 #error UNKNOWN_GET_PRINC_REALM_FUNCTIONS
2336 #endif
2337 }
2338
2339 /*
2340  * smb_krb5_principal_set_realm
2341  *
2342  * @brief Get realm of a principal
2343  *
2344  * @param[in] context           The krb5_context
2345  * @param[in] principal         The principal
2346  * @param[in] realm             The realm
2347  * @return                      0 on success, a krb5_error_code on error.
2348  *
2349  */
2350
2351 krb5_error_code smb_krb5_principal_set_realm(krb5_context context,
2352                                              krb5_principal principal,
2353                                              const char *realm)
2354 {
2355 #ifdef HAVE_KRB5_PRINCIPAL_SET_REALM /* Heimdal */
2356         return krb5_principal_set_realm(context, principal, realm);
2357 #elif defined(krb5_princ_realm) && defined(krb5_princ_set_realm) /* MIT */
2358         krb5_error_code ret;
2359         krb5_data data;
2360         krb5_data *old_data;
2361
2362         old_data = krb5_princ_realm(context, principal);
2363
2364         ret = smb_krb5_copy_data_contents(&data,
2365                                           realm,
2366                                           strlen(realm));
2367         if (ret) {
2368                 return ret;
2369         }
2370
2371         /* free realm before setting */
2372         free(old_data->data);
2373
2374         krb5_princ_set_realm(context, principal, &data);
2375
2376         return ret;
2377 #else
2378 #error UNKNOWN_PRINC_SET_REALM_FUNCTION
2379 #endif
2380 }
2381
2382
2383 /************************************************************************
2384  Routine to get the default realm from the kerberos credentials cache.
2385  Caller must free if the return value is not NULL.
2386 ************************************************************************/
2387
2388 static char *smb_krb5_get_default_realm_from_ccache(TALLOC_CTX *mem_ctx)
2389 {
2390         char *realm = NULL;
2391         krb5_context ctx = NULL;
2392         krb5_ccache cc = NULL;
2393         krb5_principal princ = NULL;
2394
2395         initialize_krb5_error_table();
2396         if (krb5_init_context(&ctx)) {
2397                 return NULL;
2398         }
2399
2400         DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2401                 "Trying to read krb5 cache: %s\n",
2402                 krb5_cc_default_name(ctx)));
2403         if (krb5_cc_default(ctx, &cc)) {
2404                 DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2405                         "failed to read default cache\n"));
2406                 goto out;
2407         }
2408         if (krb5_cc_get_principal(ctx, cc, &princ)) {
2409                 DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2410                         "failed to get default principal\n"));
2411                 goto out;
2412         }
2413
2414 #if defined(HAVE_KRB5_PRINCIPAL_GET_REALM)
2415         realm = talloc_strdup(mem_ctx, krb5_principal_get_realm(ctx, princ));
2416 #elif defined(HAVE_KRB5_PRINC_REALM)
2417         {
2418                 krb5_data *realm_data = krb5_princ_realm(ctx, princ);
2419                 realm = talloc_strndup(mem_ctx, realm_data->data, realm_data->length);
2420         }
2421 #endif
2422
2423   out:
2424
2425         if (ctx) {
2426                 if (princ) {
2427                         krb5_free_principal(ctx, princ);
2428                 }
2429                 if (cc) {
2430                         krb5_cc_close(ctx, cc);
2431                 }
2432                 krb5_free_context(ctx);
2433         }
2434
2435         return realm;
2436 }
2437
2438 /************************************************************************
2439  Routine to get the realm from a given DNS name.
2440 ************************************************************************/
2441
2442 static char *smb_krb5_get_realm_from_hostname(TALLOC_CTX *mem_ctx,
2443                                                 const char *hostname)
2444 {
2445 #if defined(HAVE_KRB5_REALM_TYPE)
2446         /* Heimdal. */
2447         krb5_realm *realm_list = NULL;
2448 #else
2449         /* MIT */
2450         char **realm_list = NULL;
2451 #endif
2452         char *realm = NULL;
2453         krb5_error_code kerr;
2454         krb5_context ctx = NULL;
2455
2456         initialize_krb5_error_table();
2457         if (krb5_init_context(&ctx)) {
2458                 return NULL;
2459         }
2460
2461         kerr = krb5_get_host_realm(ctx, hostname, &realm_list);
2462         if (kerr != 0) {
2463                 DEBUG(3,("kerberos_get_realm_from_hostname %s: "
2464                         "failed %s\n",
2465                         hostname ? hostname : "(NULL)",
2466                         error_message(kerr) ));
2467                 goto out;
2468         }
2469
2470         if (realm_list && realm_list[0]) {
2471                 realm = talloc_strdup(mem_ctx, realm_list[0]);
2472         }
2473
2474   out:
2475
2476         if (ctx) {
2477                 if (realm_list) {
2478                         krb5_free_host_realm(ctx, realm_list);
2479                         realm_list = NULL;
2480                 }
2481                 krb5_free_context(ctx);
2482                 ctx = NULL;
2483         }
2484         return realm;
2485 }
2486
2487 char *kerberos_get_principal_from_service_hostname(TALLOC_CTX *mem_ctx,
2488                                                    const char *service,
2489                                                    const char *remote_name,
2490                                                    const char *default_realm)
2491 {
2492         char *realm = NULL;
2493         char *host = NULL;
2494         char *principal;
2495         host = strchr_m(remote_name, '.');
2496         if (host) {
2497                 /* DNS name. */
2498                 realm = smb_krb5_get_realm_from_hostname(talloc_tos(),
2499                                                          remote_name);
2500         } else {
2501                 /* NetBIOS name - use our realm. */
2502                 realm = smb_krb5_get_default_realm_from_ccache(talloc_tos());
2503         }
2504
2505         if (realm == NULL || *realm == '\0') {
2506                 realm = talloc_strdup(talloc_tos(), default_realm);
2507                 if (!realm) {
2508                         return NULL;
2509                 }
2510                 DEBUG(3,("kerberos_get_principal_from_service_hostname: "
2511                          "cannot get realm from, "
2512                          "desthost %s or default ccache. Using default "
2513                          "smb.conf realm %s\n",
2514                          remote_name,
2515                          realm));
2516         }
2517
2518         principal = talloc_asprintf(mem_ctx,
2519                                     "%s/%s@%s",
2520                                     service, remote_name,
2521                                     realm);
2522         TALLOC_FREE(realm);
2523         return principal;
2524 }
2525
2526 char *smb_get_krb5_error_message(krb5_context context,
2527                                  krb5_error_code code,
2528                                  TALLOC_CTX *mem_ctx)
2529 {
2530         char *ret;
2531
2532 #if defined(HAVE_KRB5_GET_ERROR_MESSAGE) && defined(HAVE_KRB5_FREE_ERROR_MESSAGE)
2533         const char *context_error = krb5_get_error_message(context, code);
2534         if (context_error) {
2535                 ret = talloc_asprintf(mem_ctx, "%s: %s",
2536                                         error_message(code), context_error);
2537                 krb5_free_error_message(context, context_error);
2538                 return ret;
2539         }
2540 #endif
2541         ret = talloc_strdup(mem_ctx, error_message(code));
2542         return ret;
2543 }
2544
2545
2546 /**
2547 * @brief Return the kerberos library setting for "libdefaults:allow_weak_crypto"
2548 *
2549 * @param context        The krb5_context
2550 *
2551 * @return krb5_boolean
2552 *
2553 * Function returns true if weak crypto is allowd, false if not
2554 */
2555
2556 krb5_boolean smb_krb5_get_allowed_weak_crypto(krb5_context context)
2557 #if defined(HAVE_KRB5_CONFIG_GET_BOOL_DEFAULT)
2558 {
2559         return krb5_config_get_bool_default(context,
2560                                             NULL,
2561                                             FALSE,
2562                                             "libdefaults",
2563                                             "allow_weak_crypto",
2564                                             NULL);
2565 }
2566 #elif defined(HAVE_PROFILE_H) && defined(HAVE_KRB5_GET_PROFILE)
2567 {
2568 #include <profile.h>
2569         krb5_error_code ret;
2570         krb5_boolean ret_default = false;
2571         profile_t profile;
2572         int ret_profile;
2573
2574         ret = krb5_get_profile(context,
2575                                &profile);
2576         if (ret) {
2577                 return ret_default;
2578         }
2579
2580         ret = profile_get_boolean(profile,
2581                                   "libdefaults",
2582                                   "allow_weak_crypto",
2583                                   NULL, /* subsubname */
2584                                   ret_default, /* def_val */
2585                                   &ret_profile /* *ret_default */);
2586         if (ret) {
2587                 return ret_default;
2588         }
2589
2590         profile_release(profile);
2591
2592         return ret_profile;
2593 }
2594 #else
2595 #error UNKNOWN_KRB5_CONFIG_ROUTINES
2596 #endif
2597
2598 /**
2599 * @brief Return the type of a krb5_principal
2600 *
2601 * @param context        The krb5_context
2602 * @param principal      The const krb5_principal
2603 *
2604 * @return integer type of the principal
2605 */
2606 int smb_krb5_principal_get_type(krb5_context context,
2607                                 krb5_const_principal principal)
2608 {
2609 #ifdef HAVE_KRB5_PRINCIPAL_GET_TYPE /* Heimdal */
2610         return krb5_principal_get_type(context, principal);
2611 #elif defined(krb5_princ_type) /* MIT */
2612         return krb5_princ_type(context, principal);
2613 #else
2614 #error  UNKNOWN_PRINC_GET_TYPE_FUNCTION
2615 #endif
2616 }
2617
2618 /**
2619 * @brief Set the type of a krb5_principal
2620 *
2621 * @param context        The krb5_context
2622 * @param principal      The const krb5_principal
2623 * @param type           The principal type
2624 *
2625 */
2626 void smb_krb5_principal_set_type(krb5_context context,
2627                                  krb5_principal principal,
2628                                  int type)
2629 {
2630 #ifdef HAVE_KRB5_PRINCIPAL_SET_TYPE /* Heimdal */
2631         krb5_principal_set_type(context, principal, type);
2632 #elif defined(krb5_princ_type) /* MIT */
2633         krb5_princ_type(context, principal) = type;
2634 #else
2635 #error  UNKNOWN_PRINC_SET_TYPE_FUNCTION
2636 #endif
2637 }
2638
2639 /**
2640 * @brief Generate a krb5 warning, forwarding to com_err
2641 *
2642 * @param context        The krb5_context
2643 * @param fmt            The message format
2644 * @param ...            The message arguments
2645 *
2646 * @return
2647 */
2648 #if !defined(HAVE_KRB5_WARNX)
2649 krb5_error_code krb5_warnx(krb5_context context, const char *fmt, ...)
2650 {
2651         va_list args;
2652
2653         va_start(args, fmt);
2654         com_err_va("kdb_samba", errno, fmt, args);
2655         va_end(args);
2656
2657         return 0;
2658 }
2659 #endif
2660
2661 krb5_error_code smb_krb5_cc_copy_creds(krb5_context context,
2662                                        krb5_ccache incc, krb5_ccache outcc)
2663 {
2664 #ifdef HAVE_KRB5_CC_COPY_CACHE /* Heimdal */
2665         return krb5_cc_copy_cache(context, incc, outcc);
2666 #elif defined(HAVE_KRB5_CC_COPY_CREDS)
2667         return krb5_cc_copy_creds(context, incc, outcc);
2668 #else
2669 #error UNKNOWN_KRB5_CC_COPY_CACHE_OR_CREDS_FUNCTION
2670 #endif
2671 }
2672
2673 /**********************************************************
2674  * ADS KRB5 CALLS
2675  **********************************************************/
2676
2677 static bool ads_cleanup_expired_creds(krb5_context context,
2678                                       krb5_ccache  ccache,
2679                                       krb5_creds  *credsp)
2680 {
2681         krb5_error_code retval;
2682         const char *cc_type = krb5_cc_get_type(context, ccache);
2683
2684         DEBUG(3, ("ads_cleanup_expired_creds: Ticket in ccache[%s:%s] expiration %s\n",
2685                   cc_type, krb5_cc_get_name(context, ccache),
2686                   http_timestring(talloc_tos(), credsp->times.endtime)));
2687
2688         /* we will probably need new tickets if the current ones
2689            will expire within 10 seconds.
2690         */
2691         if (credsp->times.endtime >= (time(NULL) + 10))
2692                 return false;
2693
2694         /* heimdal won't remove creds from a file ccache, and
2695            perhaps we shouldn't anyway, since internally we
2696            use memory ccaches, and a FILE one probably means that
2697            we're using creds obtained outside of our exectuable
2698         */
2699         if (strequal(cc_type, "FILE")) {
2700                 DEBUG(5, ("ads_cleanup_expired_creds: We do not remove creds from a %s ccache\n", cc_type));
2701                 return false;
2702         }
2703
2704         retval = krb5_cc_remove_cred(context, ccache, 0, credsp);
2705         if (retval) {
2706                 DEBUG(1, ("ads_cleanup_expired_creds: krb5_cc_remove_cred failed, err %s\n",
2707                           error_message(retval)));
2708                 /* If we have an error in this, we want to display it,
2709                    but continue as though we deleted it */
2710         }
2711         return true;
2712 }
2713
2714 /* Allocate and setup the auth context into the state we need. */
2715
2716 static krb5_error_code ads_setup_auth_context(krb5_context context,
2717                                               krb5_auth_context *auth_context)
2718 {
2719         krb5_error_code retval;
2720
2721         retval = krb5_auth_con_init(context, auth_context );
2722         if (retval) {
2723                 DEBUG(1,("krb5_auth_con_init failed (%s)\n",
2724                         error_message(retval)));
2725                 return retval;
2726         }
2727
2728         /* Ensure this is an addressless ticket. */
2729         retval = krb5_auth_con_setaddrs(context, *auth_context, NULL, NULL);
2730         if (retval) {
2731                 DEBUG(1,("krb5_auth_con_setaddrs failed (%s)\n",
2732                         error_message(retval)));
2733         }
2734
2735         return retval;
2736 }
2737
2738 #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)
2739 static krb5_error_code ads_create_gss_checksum(krb5_data *in_data, /* [inout] */
2740                                                uint32_t gss_flags)
2741 {
2742         unsigned int orig_length = in_data->length;
2743         unsigned int base_cksum_size = GSSAPI_CHECKSUM_SIZE;
2744         char *gss_cksum = NULL;
2745
2746         if (orig_length) {
2747                 /* Extra length field for delgated ticket. */
2748                 base_cksum_size += 4;
2749         }
2750
2751         if ((unsigned int)base_cksum_size + orig_length <
2752                         (unsigned int)base_cksum_size) {
2753                 return EINVAL;
2754         }
2755
2756         gss_cksum = (char *)SMB_MALLOC(base_cksum_size + orig_length);
2757         if (gss_cksum == NULL) {
2758                 return ENOMEM;
2759         }
2760
2761         memset(gss_cksum, '\0', base_cksum_size + orig_length);
2762         SIVAL(gss_cksum, 0, GSSAPI_BNDLENGTH);
2763
2764         /*
2765          * GSS_C_NO_CHANNEL_BINDINGS means 16 zero bytes.
2766          * This matches the behavior of heimdal and mit.
2767          *
2768          * And it is needed to work against some closed source
2769          * SMB servers.
2770          *
2771          * See bug #7883
2772          */
2773         memset(&gss_cksum[4], 0x00, GSSAPI_BNDLENGTH);
2774
2775         SIVAL(gss_cksum, 20, gss_flags);
2776
2777         if (orig_length) {
2778                 SSVAL(gss_cksum, 24, 1); /* The Delegation Option identifier */
2779                 SSVAL(gss_cksum, 26, orig_length);
2780                 /* Copy the kerberos KRB_CRED data */
2781                 memcpy(gss_cksum + 28, in_data->data, orig_length);
2782                 free(in_data->data);
2783                 in_data->data = NULL;
2784                 in_data->length = 0;
2785         }
2786         in_data->data = gss_cksum;
2787         in_data->length = base_cksum_size + orig_length;
2788         return 0;
2789 }
2790 #endif
2791
2792 /*
2793  * We can't use krb5_mk_req because w2k wants the service to be in a particular
2794  * format.
2795  */
2796 static krb5_error_code ads_krb5_mk_req(krb5_context context,
2797                                        krb5_auth_context *auth_context,
2798                                        const krb5_flags ap_req_options,
2799                                        const char *principal,
2800                                        krb5_ccache ccache,
2801                                        krb5_data *outbuf,
2802                                        time_t *expire_time,
2803                                        const char *impersonate_princ_s)
2804 {
2805         krb5_error_code retval;
2806         krb5_principal server;
2807         krb5_principal impersonate_princ = NULL;
2808         krb5_creds *credsp;
2809         krb5_creds creds;
2810         krb5_data in_data;
2811         bool creds_ready = false;
2812         int i = 0, maxtries = 3;
2813         bool ok;
2814
2815         ZERO_STRUCT(in_data);
2816
2817         retval = smb_krb5_parse_name(context, principal, &server);
2818         if (retval != 0) {
2819                 DEBUG(1,("ads_krb5_mk_req: Failed to parse principal %s\n", principal));
2820                 return retval;
2821         }
2822
2823         if (impersonate_princ_s) {
2824                 retval = smb_krb5_parse_name(context, impersonate_princ_s,
2825                                              &impersonate_princ);
2826                 if (retval) {
2827                         DEBUG(1,("ads_krb5_mk_req: Failed to parse principal %s\n", impersonate_princ_s));
2828                         goto cleanup_princ;
2829                 }
2830         }
2831
2832         /* obtain ticket & session key */
2833         ZERO_STRUCT(creds);
2834         if ((retval = krb5_copy_principal(context, server, &creds.server))) {
2835                 DEBUG(1,("ads_krb5_mk_req: krb5_copy_principal failed (%s)\n",
2836                          error_message(retval)));
2837                 goto cleanup_princ;
2838         }
2839
2840         retval = krb5_cc_get_principal(context, ccache, &creds.client);
2841         if (retval != 0) {
2842                 /* This can commonly fail on smbd startup with no ticket in the cache.
2843                  * Report at higher level than 1. */
2844                 DEBUG(3,("ads_krb5_mk_req: krb5_cc_get_principal failed (%s)\n",
2845                          error_message(retval)));
2846                 goto cleanup_creds;
2847         }
2848
2849         while (!creds_ready && (i < maxtries)) {
2850
2851                 retval = smb_krb5_get_credentials(context,
2852                                                   ccache,
2853                                                   creds.client,
2854                                                   creds.server,
2855                                                   impersonate_princ,
2856                                                   &credsp);
2857                 if (retval != 0) {
2858                         DBG_WARNING("smb_krb5_get_credentials failed for %s "
2859                                     "(%s)\n",
2860                                     principal,
2861                                     error_message(retval));
2862                         goto cleanup_creds;
2863                 }
2864
2865                 /* cope with ticket being in the future due to clock skew */
2866                 if ((unsigned)credsp->times.starttime > time(NULL)) {
2867                         time_t t = time(NULL);
2868                         int time_offset =(int)((unsigned)credsp->times.starttime-t);
2869                         DEBUG(4,("ads_krb5_mk_req: Advancing clock by %d seconds to cope with clock skew\n", time_offset));
2870                         krb5_set_real_time(context, t + time_offset + 1, 0);
2871                 }
2872
2873                 ok = ads_cleanup_expired_creds(context, ccache, credsp);
2874                 if (!ok) {
2875                         creds_ready = true;
2876                 }
2877
2878                 i++;
2879         }
2880
2881         DBG_DEBUG("Ticket (%s) in ccache (%s:%s) is valid until: (%s - %u)\n",
2882                   principal,
2883                   krb5_cc_get_type(context, ccache),
2884                   krb5_cc_get_name(context, ccache),
2885                   http_timestring(talloc_tos(),
2886                                   (unsigned)credsp->times.endtime),
2887                   (unsigned)credsp->times.endtime);
2888
2889         if (expire_time) {
2890                 *expire_time = (time_t)credsp->times.endtime;
2891         }
2892
2893         /* Allocate the auth_context. */
2894         retval = ads_setup_auth_context(context, auth_context);
2895         if (retval != 0) {
2896                 DBG_WARNING("ads_setup_auth_context failed (%s)\n",
2897                             error_message(retval));
2898                 goto cleanup_creds;
2899         }
2900
2901 #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)
2902         {
2903                 uint32_t gss_flags = 0;
2904
2905                 if (credsp->ticket_flags & TKT_FLG_OK_AS_DELEGATE) {
2906                         /*
2907                          * Fetch a forwarded TGT from the KDC so that we can
2908                          * hand off a 2nd ticket as part of the kerberos
2909                          * exchange.
2910                          */
2911
2912                         DBG_INFO("Server marked as OK to delegate to, building "
2913                                  "forwardable TGT\n");
2914
2915                         retval = krb5_auth_con_setuseruserkey(context,
2916                                         *auth_context,
2917                                         &credsp->keyblock );
2918                         if (retval != 0) {
2919                                 DBG_WARNING("krb5_auth_con_setuseruserkey "
2920                                             "failed (%s)\n",
2921                                             error_message(retval)));
2922                                 goto cleanup_creds;
2923                         }
2924
2925                         /* Must use a subkey for forwarded tickets. */
2926                         retval = krb5_auth_con_setflags(context,
2927                                                         *auth_context,
2928                                                         KRB5_AUTH_CONTEXT_USE_SUBKEY);
2929                         if (retval != 0) {
2930                                 DBG_WARNING("krb5_auth_con_setflags failed (%s)\n",
2931                                             error_message(retval)));
2932                                 goto cleanup_creds;
2933                         }
2934
2935                         retval = krb5_fwd_tgt_creds(context,/* Krb5 context [in] */
2936                                 *auth_context,  /* Authentication context [in] */
2937                                 discard_const_p(char, KRB5_TGS_NAME),  /* Ticket service name ("krbtgt") [in] */
2938                                 credsp->client, /* Client principal for the tgt [in] */
2939                                 credsp->server, /* Server principal for the tgt [in] */
2940                                 ccache,         /* Credential cache to use for storage [in] */
2941                                 1,              /* Turn on for "Forwardable ticket" [in] */
2942                                 &in_data );     /* Resulting response [out] */
2943
2944                         if (retval) {
2945                                 DBG_INFO("krb5_fwd_tgt_creds failed (%s)\n",
2946                                          error_message(retval));
2947
2948                                 /*
2949                                  * This is not fatal. Delete the *auth_context and continue
2950                                  * with krb5_mk_req_extended to get a non-forwardable ticket.
2951                                  */
2952
2953                                 if (in_data.data) {
2954                                         free( in_data.data );
2955                                         in_data.data = NULL;
2956                                         in_data.length = 0;
2957                                 }
2958                                 krb5_auth_con_free(context, *auth_context);
2959                                 *auth_context = NULL;
2960                                 retval = ads_setup_auth_context(context, auth_context);
2961                                 if (retval != 0) {
2962                                         DBG_WARNING("ads_setup_auth_context failed (%s)\n",
2963                                                     error_message(retval)));
2964                                         goto cleanup_creds;
2965                                 }
2966                         } else {
2967                                 /* We got a delegated ticket. */
2968                                 gss_flags |= GSS_C_DELEG_FLAG;
2969                         }
2970                 }
2971
2972                 /* Frees and reallocates in_data into a GSS checksum blob. */
2973                 retval = ads_create_gss_checksum(&in_data, gss_flags);
2974                 if (retval != 0) {
2975                         goto cleanup_data;
2976                 }
2977
2978                 /* We always want GSS-checksum types. */
2979                 retval = krb5_auth_con_set_req_cksumtype(context, *auth_context, GSSAPI_CHECKSUM );
2980                 if (retval != 0) {
2981                         DEBUG(1,("krb5_auth_con_set_req_cksumtype failed (%s)\n",
2982                                 error_message(retval)));
2983                         goto cleanup_data;
2984                 }
2985         }
2986 #endif
2987
2988         retval = krb5_mk_req_extended(context, auth_context, ap_req_options,
2989                                       &in_data, credsp, outbuf);
2990         if (retval != 0) {
2991                 DBG_WARNING("krb5_mk_req_extended failed (%s)\n",
2992                             error_message(retval));
2993         }
2994
2995 #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)
2996 cleanup_data:
2997 #endif
2998
2999         if (in_data.data) {
3000                 free( in_data.data );
3001                 in_data.length = 0;
3002         }
3003
3004         krb5_free_creds(context, credsp);
3005
3006 cleanup_creds:
3007         krb5_free_cred_contents(context, &creds);
3008
3009 cleanup_princ:
3010         krb5_free_principal(context, server);
3011         if (impersonate_princ) {
3012                 krb5_free_principal(context, impersonate_princ);
3013         }
3014
3015         return retval;
3016 }
3017
3018 /*
3019   get a kerberos5 ticket for the given service
3020 */
3021 int ads_krb5_cli_get_ticket(TALLOC_CTX *mem_ctx,
3022                             const char *principal,
3023                             time_t time_offset,
3024                             DATA_BLOB *ticket,
3025                             DATA_BLOB *session_key_krb5,
3026                             uint32_t extra_ap_opts, const char *ccname,
3027                             time_t *tgs_expire,
3028                             const char *impersonate_princ_s)
3029 {
3030         krb5_error_code retval;
3031         krb5_data packet;
3032         krb5_context context = NULL;
3033         krb5_ccache ccdef = NULL;
3034         krb5_auth_context auth_context = NULL;
3035         krb5_enctype enc_types[] = {
3036 #ifdef HAVE_ENCTYPE_AES256_CTS_HMAC_SHA1_96
3037                 ENCTYPE_AES256_CTS_HMAC_SHA1_96,
3038 #endif
3039 #ifdef HAVE_ENCTYPE_AES128_CTS_HMAC_SHA1_96
3040                 ENCTYPE_AES128_CTS_HMAC_SHA1_96,
3041 #endif
3042                 ENCTYPE_ARCFOUR_HMAC,
3043                 ENCTYPE_DES_CBC_MD5,
3044                 ENCTYPE_DES_CBC_CRC,
3045                 ENCTYPE_NULL};
3046         bool ok;
3047
3048         initialize_krb5_error_table();
3049         retval = krb5_init_context(&context);
3050         if (retval != 0) {
3051                 DBG_WARNING("krb5_init_context failed (%s)\n",
3052                             error_message(retval));
3053                 goto failed;
3054         }
3055
3056         if (time_offset != 0) {
3057                 krb5_set_real_time(context, time(NULL) + time_offset, 0);
3058         }
3059
3060         retval = krb5_cc_resolve(context,
3061                                  ccname ? ccname : krb5_cc_default_name(context),
3062                                  &ccdef);
3063         if (retval != 0) {
3064                 DBG_WARNING("krb5_cc_default failed (%s)\n",
3065                             error_message(retval));
3066                 goto failed;
3067         }
3068
3069         retval = krb5_set_default_tgs_ktypes(context, enc_types);
3070         if (retval != 0) {
3071                 DBG_WARNING("krb5_set_default_tgs_ktypes failed (%s)\n",
3072                             error_message(retval));
3073                 goto failed;
3074         }
3075
3076         retval = ads_krb5_mk_req(context,
3077                                  &auth_context,
3078                                  AP_OPTS_USE_SUBKEY | (krb5_flags)extra_ap_opts,
3079                                  principal,
3080                                  ccdef,
3081                                  &packet,
3082                                  tgs_expire,
3083                                  impersonate_princ_s);
3084         if (retval != 0) {
3085                 goto failed;
3086         }
3087
3088         ok = smb_krb5_get_smb_session_key(mem_ctx,
3089                                           context,
3090                                           auth_context,
3091                                           session_key_krb5,
3092                                           false);
3093         if (!ok) {
3094                 retval = ENOMEM;
3095                 goto failed;
3096         }
3097
3098         *ticket = data_blob_talloc(mem_ctx, packet.data, packet.length);
3099
3100         smb_krb5_free_data_contents(context, &packet);
3101
3102 failed:
3103
3104         if (context) {
3105                 if (ccdef) {
3106                         krb5_cc_close(context, ccdef);
3107                 }
3108                 if (auth_context) {
3109                         krb5_auth_con_free(context, auth_context);
3110                 }
3111                 krb5_free_context(context);
3112         }
3113
3114         return retval;
3115 }
3116
3117 #else /* HAVE_KRB5 */
3118 /* This saves a few linking headaches */
3119 int ads_krb5_cli_get_ticket(TALLOC_CTX *mem_ctx,
3120                             const char *principal,
3121                             time_t time_offset,
3122                             DATA_BLOB *ticket,
3123                             DATA_BLOB *session_key_krb5,
3124                             uint32_t extra_ap_opts, const char *ccname,
3125                             time_t *tgs_expire,
3126                             const char *impersonate_princ_s)
3127 {
3128          DEBUG(0,("NO KERBEROS SUPPORT\n"));
3129          return 1;
3130 }
3131
3132 #endif /* HAVE_KRB5 */