source3/libsmb/clikrb5.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
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 #ifdef HAVE_KRB5
  25
  26 #ifdef HAVE_KRB5_KEYBLOCK_KEYVALUE
  27 #define KRB5_KEY_TYPE(k)        ((k)->keytype)
  28 #define KRB5_KEY_LENGTH(k)      ((k)->keyvalue.length)
  29 #define KRB5_KEY_DATA(k)        ((k)->keyvalue.data)
  30 #else
  31 #define KRB5_KEY_TYPE(k)        ((k)->enctype)
  32 #define KRB5_KEY_LENGTH(k)      ((k)->length)
  33 #define KRB5_KEY_DATA(k)        ((k)->contents)
  34 #endif /* HAVE_KRB5_KEYBLOCK_KEYVALUE */
  35
  36 #ifndef HAVE_KRB5_SET_REAL_TIME
  37 /*
  38  * This function is not in the Heimdal mainline.
  39  */
  40  krb5_error_code krb5_set_real_time(krb5_context context, int32_t seconds, int32_t microseconds)
  41 {
  42         krb5_error_code ret;
  43         int32_t sec, usec;
  44
  45         ret = krb5_us_timeofday(context, &sec, &usec);
  46         if (ret)
  47                 return ret;
  48
  49         context->kdc_sec_offset = seconds - sec;
  50         context->kdc_usec_offset = microseconds - usec;
  51
  52         return 0;
  53 }
  54 #endif
  55
  56 #if defined(HAVE_KRB5_SET_DEFAULT_IN_TKT_ETYPES) && !defined(HAVE_KRB5_SET_DEFAULT_TGS_KTYPES)
  57  krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc)
  58 {
  59         return krb5_set_default_in_tkt_etypes(ctx, enc);
  60 }
  61 #endif
  62
  63 #if defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS)
  64 /* HEIMDAL */
  65  void setup_kaddr( krb5_address *pkaddr, struct sockaddr *paddr)
  66 {
  67         pkaddr->addr_type = KRB5_ADDRESS_INET;
  68         pkaddr->address.length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
  69         pkaddr->address.data = (char *)&(((struct sockaddr_in *)paddr)->sin_addr);
  70 }
  71 #elif defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS)
  72 /* MIT */
  73  void setup_kaddr( krb5_address *pkaddr, struct sockaddr *paddr)
  74 {
  75         pkaddr->addrtype = ADDRTYPE_INET;
  76         pkaddr->length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
  77         pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in *)paddr)->sin_addr);
  78 }
  79 #else
  80  __ERROR__XX__UNKNOWN_ADDRTYPE
  81 #endif
  82
  83 #if defined(HAVE_KRB5_PRINCIPAL2SALT) && defined(HAVE_KRB5_USE_ENCTYPE) && defined(HAVE_KRB5_STRING_TO_KEY)
  84  int create_kerberos_key_from_string(krb5_context context,
  85                                         krb5_principal host_princ,
  86                                         krb5_data *password,
  87                                         krb5_keyblock *key,
  88                                         krb5_enctype enctype)
  89 {
  90         int ret;
  91         krb5_data salt;
  92         krb5_encrypt_block eblock;
  93
  94         ret = krb5_principal2salt(context, host_princ, &salt);
  95         if (ret) {
  96                 DEBUG(1,("krb5_principal2salt failed (%s)\n", error_message(ret)));
  97                 return ret;
  98         }
  99         krb5_use_enctype(context, &eblock, enctype);
 100         ret = krb5_string_to_key(context, &eblock, key, password, &salt);
 101         SAFE_FREE(salt.data);
 102         return ret;
 103 }
 104 #elif defined(HAVE_KRB5_GET_PW_SALT) && defined(HAVE_KRB5_STRING_TO_KEY_SALT)
 105  int create_kerberos_key_from_string(krb5_context context,
 106                                         krb5_principal host_princ,
 107                                         krb5_data *password,
 108                                         krb5_keyblock *key,
 109                                         krb5_enctype enctype)
 110 {
 111         int ret;
 112         krb5_salt salt;
 113
 114         ret = krb5_get_pw_salt(context, host_princ, &salt);
 115         if (ret) {
 116                 DEBUG(1,("krb5_get_pw_salt failed (%s)\n", error_message(ret)));
 117                 return ret;
 118         }
 119         return krb5_string_to_key_salt(context, enctype, password->data,
 120                 salt, key);
 121 }
 122 #else
 123  __ERROR_XX_UNKNOWN_CREATE_KEY_FUNCTIONS
 124 #endif
 125
 126 #if defined(HAVE_KRB5_GET_PERMITTED_ENCTYPES)
 127  krb5_error_code get_kerberos_allowed_etypes(krb5_context context,
 128                                             krb5_enctype **enctypes)
 129 {
 130         return krb5_get_permitted_enctypes(context, enctypes);
 131 }
 132 #elif defined(HAVE_KRB5_GET_DEFAULT_IN_TKT_ETYPES)
 133  krb5_error_code get_kerberos_allowed_etypes(krb5_context context,
 134                                             krb5_enctype **enctypes)
 135 {
 136         return krb5_get_default_in_tkt_etypes(context, enctypes);
 137 }
 138 #else
 139 #error UNKNOWN_GET_ENCTYPES_FUNCTIONS
 140 #endif
 141
 142  void free_kerberos_etypes(krb5_context context,
 143                            krb5_enctype *enctypes)
 144 {
 145 #if defined(HAVE_KRB5_FREE_KTYPES)
 146         krb5_free_ktypes(context, enctypes);
 147         return;
 148 #else
 149         SAFE_FREE(enctypes);
 150         return;
 151 #endif
 152 }
 153
 154 #if defined(HAVE_KRB5_AUTH_CON_SETKEY) && !defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY)
 155  krb5_error_code krb5_auth_con_setuseruserkey(krb5_context context,
 156                                         krb5_auth_context auth_context,
 157                                         krb5_keyblock *keyblock)
 158 {
 159         return krb5_auth_con_setkey(context, auth_context, keyblock);
 160 }
 161 #endif
 162
 163  void get_auth_data_from_tkt(DATA_BLOB *auth_data, krb5_ticket *tkt)
 164 {
 165 #if defined(HAVE_KRB5_TKT_ENC_PART2)
 166         if (tkt->enc_part2)
 167                 *auth_data = data_blob(tkt->enc_part2->authorization_data[0]->contents,
 168                         tkt->enc_part2->authorization_data[0]->length);
 169 #else
 170         if (tkt->ticket.authorization_data && tkt->ticket.authorization_data->len)
 171                 *auth_data = data_blob(tkt->ticket.authorization_data->val->ad_data.data,
 172                         tkt->ticket.authorization_data->val->ad_data.length);
 173 #endif
 174 }
 175
 176  krb5_const_principal get_principal_from_tkt(krb5_ticket *tkt)
 177 {
 178 #if defined(HAVE_KRB5_TKT_ENC_PART2)
 179         return tkt->enc_part2->client;
 180 #else
 181         return tkt->client;
 182 #endif
 183 }
 184
 185 #if !defined(HAVE_KRB5_LOCATE_KDC)
 186  krb5_error_code krb5_locate_kdc(krb5_context ctx, const krb5_data *realm, struct sockaddr **addr_pp, int *naddrs, int get_masters)
 187 {
 188         krb5_krbhst_handle hnd;
 189         krb5_krbhst_info *hinfo;
 190         krb5_error_code rc;
 191         int num_kdcs, i;
 192         struct sockaddr *sa;
 193         struct addrinfo *ai;
 194
 195         *addr_pp = NULL;
 196         *naddrs = 0;
 197
 198         rc = krb5_krbhst_init(ctx, realm->data, KRB5_KRBHST_KDC, &hnd);
 199         if (rc) {
 200                 DEBUG(0, ("krb5_locate_kdc: krb5_krbhst_init failed (%s)\n", error_message(rc)));
 201                 return rc;
 202         }
 203
 204         for ( num_kdcs = 0; (rc = krb5_krbhst_next(ctx, hnd, &hinfo) == 0); num_kdcs++)
 205                 ;
 206
 207         krb5_krbhst_reset(ctx, hnd);
 208
 209         if (!num_kdcs) {
 210                 DEBUG(0, ("krb5_locate_kdc: zero kdcs found !\n"));
 211                 krb5_krbhst_free(ctx, hnd);
 212                 return -1;
 213         }
 214
 215         sa = malloc( sizeof(struct sockaddr) * num_kdcs );
 216         if (!sa) {
 217                 DEBUG(0, ("krb5_locate_kdc: malloc failed\n"));
 218                 krb5_krbhst_free(ctx, hnd);
 219                 naddrs = 0;
 220                 return -1;
 221         }
 222
 223         *addr_pp = malloc(sizeof(struct sockaddr) * num_kdcs);
 224         memset(*addr_pp, '\0', sizeof(struct sockaddr) * num_kdcs );
 225
 226         for (i = 0; i < num_kdcs && (rc = krb5_krbhst_next(ctx, hnd, &hinfo) == 0); i++) {
 227
 228 #if defined(HAVE_KRB5_KRBHST_GET_ADDRINFO)
 229                 rc = krb5_krbhst_get_addrinfo(ctx, hinfo, &ai);
 230                 if (rc) {
 231                         DEBUG(0,("krb5_krbhst_get_addrinfo failed: %s\n", error_message(rc)));
 232                         continue;
 233                 }
 234 #endif
 235                 if (hinfo->ai && hinfo->ai->ai_family == AF_INET)
 236                         memcpy(&sa[i], hinfo->ai->ai_addr, sizeof(struct sockaddr));
 237         }
 238
 239         krb5_krbhst_free(ctx, hnd);
 240
 241         *naddrs = num_kdcs;
 242         *addr_pp = sa;
 243         return 0;
 244 }
 245 #endif
 246
 247 #if !defined(HAVE_KRB5_FREE_UNPARSED_NAME)
 248  void krb5_free_unparsed_name(krb5_context context, char *val)
 249 {
 250         SAFE_FREE(val);
 251 }
 252 #endif
 253
 254 void kerberos_set_creds_enctype(krb5_creds *pcreds, int enctype)
 255 {
 256 #if defined(HAVE_KRB5_KEYBLOCK_IN_CREDS)
 257         KRB5_KEY_TYPE((&pcreds->keyblock)) = enctype;
 258 #elif defined(HAVE_KRB5_SESSION_IN_CREDS)
 259         KRB5_KEY_TYPE((&pcreds->session)) = enctype;
 260 #else
 261 #error UNKNOWN_KEYBLOCK_MEMBER_IN_KRB5_CREDS_STRUCT
 262 #endif
 263 }
 264
 265 static BOOL ads_cleanup_expired_creds(krb5_context context,
 266                                       krb5_ccache  ccache,
 267                                       krb5_creds  *credsp)
 268 {
 269         krb5_error_code retval;
 270
 271         DEBUG(3, ("Ticket in ccache[%s] expiration %s\n",
 272                   krb5_cc_default_name(context),
 273                   http_timestring(credsp->times.endtime)));
 274
 275         /* we will probably need new tickets if the current ones
 276            will expire within 10 seconds.
 277         */
 278         if (credsp->times.endtime >= (time(NULL) + 10))
 279                 return False;
 280
 281         /* heimdal won't remove creds from a file ccache, and
 282            perhaps we shouldn't anyway, since internally we
 283            use memory ccaches, and a FILE one probably means that
 284            we're using creds obtained outside of our exectuable
 285         */
 286         if (StrCaseCmp(krb5_cc_get_type(context, ccache), "FILE") == 0) {
 287                 DEBUG(5, ("We do not remove creds from a FILE ccache\n"));
 288                 return False;
 289         }
 290
 291         retval = krb5_cc_remove_cred(context, ccache, 0, credsp);
 292         if (retval) {
 293                 DEBUG(1, ("krb5_cc_remove_cred failed, err %s\n",
 294                           error_message(retval)));
 295                 /* If we have an error in this, we want to display it,
 296                    but continue as though we deleted it */
 297         }
 298         return True;
 299 }
 300
 301 /*
 302   we can't use krb5_mk_req because w2k wants the service to be in a particular format
 303 */
 304 static krb5_error_code ads_krb5_mk_req(krb5_context context,
 305                                        krb5_auth_context *auth_context,
 306                                        const krb5_flags ap_req_options,
 307                                        const char *principal,
 308                                        krb5_ccache ccache,
 309                                        krb5_data *outbuf)
 310 {
 311         krb5_error_code           retval;
 312         krb5_principal    server;
 313         krb5_creds              * credsp;
 314         krb5_creds                creds;
 315         krb5_data in_data;
 316         BOOL creds_ready = False;
 317
 318         retval = krb5_parse_name(context, principal, &server);
 319         if (retval) {
 320                 DEBUG(1,("Failed to parse principal %s\n", principal));
 321                 return retval;
 322         }
 323
 324         /* obtain ticket & session key */
 325         ZERO_STRUCT(creds);
 326         if ((retval = krb5_copy_principal(context, server, &creds.server))) {
 327                 DEBUG(1,("krb5_copy_principal failed (%s)\n",
 328                          error_message(retval)));
 329                 goto cleanup_princ;
 330         }
 331
 332         if ((retval = krb5_cc_get_principal(context, ccache, &creds.client))) {
 333                 DEBUG(1,("krb5_cc_get_principal failed (%s)\n",
 334                          error_message(retval)));
 335                 goto cleanup_creds;
 336         }
 337
 338         while(!creds_ready) {
 339                 if ((retval = krb5_get_credentials(context, 0, ccache,
 340                                                    &creds, &credsp))) {
 341                         DEBUG(1,("krb5_get_credentials failed for %s (%s)\n",
 342                                  principal, error_message(retval)));
 343                         goto cleanup_creds;
 344                 }
 345
 346                 /* cope with ticket being in the future due to clock skew */
 347                 if ((unsigned)credsp->times.starttime > time(NULL)) {
 348                         time_t t = time(NULL);
 349                         int time_offset =(unsigned)credsp->times.starttime-t;
 350                         DEBUG(4,("Advancing clock by %d seconds to cope with clock skew\n", time_offset));
 351                         krb5_set_real_time(context, t + time_offset + 1, 0);
 352                 }
 353
 354                 if (!ads_cleanup_expired_creds(context, ccache, credsp))
 355                         creds_ready = True;
 356         }
 357
 358         DEBUG(10,("Ticket (%s) in ccache (%s) is valid until: (%s - %d)\n",
 359                   principal, krb5_cc_default_name(context),
 360                   http_timestring((unsigned)credsp->times.endtime),
 361                   (unsigned)credsp->times.endtime));
 362
 363         in_data.length = 0;
 364         retval = krb5_mk_req_extended(context, auth_context, ap_req_options,
 365                                       &in_data, credsp, outbuf);
 366         if (retval) {
 367                 DEBUG(1,("krb5_mk_req_extended failed (%s)\n",
 368                          error_message(retval)));
 369         }
 370
 371         krb5_free_creds(context, credsp);
 372
 373 cleanup_creds:
 374         krb5_free_cred_contents(context, &creds);
 375
 376 cleanup_princ:
 377         krb5_free_principal(context, server);
 378
 379         return retval;
 380 }
 381
 382 /*
 383   get a kerberos5 ticket for the given service
 384 */
 385 int cli_krb5_get_ticket(const char *principal, time_t time_offset,
 386                         DATA_BLOB *ticket, DATA_BLOB *session_key_krb5)
 387 {
 388         krb5_error_code retval;
 389         krb5_data packet;
 390         krb5_context context = NULL;
 391         krb5_ccache ccdef = NULL;
 392         krb5_auth_context auth_context = NULL;
 393         krb5_enctype enc_types[] = {
 394 #ifdef ENCTYPE_ARCFOUR_HMAC
 395                 ENCTYPE_ARCFOUR_HMAC,
 396 #endif
 397                 ENCTYPE_DES_CBC_MD5,
 398                 ENCTYPE_DES_CBC_CRC,
 399                 ENCTYPE_NULL};
 400
 401         retval = krb5_init_context(&context);
 402         if (retval) {
 403                 DEBUG(1,("krb5_init_context failed (%s)\n",
 404                          error_message(retval)));
 405                 goto failed;
 406         }
 407
 408         if (time_offset != 0) {
 409                 krb5_set_real_time(context, time(NULL) + time_offset, 0);
 410         }
 411
 412         if ((retval = krb5_cc_default(context, &ccdef))) {
 413                 DEBUG(1,("krb5_cc_default failed (%s)\n",
 414                          error_message(retval)));
 415                 goto failed;
 416         }
 417
 418         if ((retval = krb5_set_default_tgs_ktypes(context, enc_types))) {
 419                 DEBUG(1,("krb5_set_default_tgs_ktypes failed (%s)\n",
 420                          error_message(retval)));
 421                 goto failed;
 422         }
 423
 424         if ((retval = ads_krb5_mk_req(context,
 425                                         &auth_context,
 426                                         AP_OPTS_USE_SUBKEY,
 427                                         principal,
 428                                         ccdef, &packet))) {
 429                 goto failed;
 430         }
 431
 432         get_krb5_smb_session_key(context, auth_context, session_key_krb5, False);
 433
 434         *ticket = data_blob(packet.data, packet.length);
 435
 436 /* Hmm, heimdal dooesn't have this - what's the correct call? */
 437 #ifdef HAVE_KRB5_FREE_DATA_CONTENTS
 438         krb5_free_data_contents(context, &packet);
 439 #endif
 440
 441 failed:
 442
 443         if ( context ) {
 444                 if (ccdef)
 445                         krb5_cc_close(context, ccdef);
 446                 if (auth_context)
 447                         krb5_auth_con_free(context, auth_context);
 448                 krb5_free_context(context);
 449         }
 450
 451         return retval;
 452 }
 453
 454  BOOL get_krb5_smb_session_key(krb5_context context, krb5_auth_context auth_context, DATA_BLOB *session_key, BOOL remote)
 455  {
 456         krb5_keyblock *skey;
 457         krb5_error_code err;
 458         BOOL ret = False;
 459
 460         if (remote)
 461                 err = krb5_auth_con_getremotesubkey(context, auth_context, &skey);
 462         else
 463                 err = krb5_auth_con_getlocalsubkey(context, auth_context, &skey);
 464         if (err == 0 && skey != NULL) {
 465                 DEBUG(10, ("Got KRB5 session key of length %d\n",  KRB5_KEY_LENGTH(skey)));
 466                 *session_key = data_blob(KRB5_KEY_DATA(skey), KRB5_KEY_LENGTH(skey));
 467                 dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
 468
 469                 ret = True;
 470
 471                 krb5_free_keyblock(context, skey);
 472         } else {
 473                 DEBUG(10, ("KRB5 error getting session key %d\n", err));
 474         }
 475
 476         return ret;
 477  }
 478
 479
 480 #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING) && !defined(HAVE_KRB5_PRINC_COMPONENT)
 481  const krb5_data *krb5_princ_component(krb5_context context, krb5_principal principal, int i )
 482 {
 483         static krb5_data kdata;
 484
 485         kdata.data = krb5_principal_get_comp_string(context, principal, i);
 486         kdata.length = strlen(kdata.data);
 487         return &kdata;
 488 }
 489 #endif
 490
 491  krb5_error_code smb_krb5_kt_free_entry(krb5_context context, krb5_keytab_entry *kt_entry)
 492 {
 493 #if defined(HAVE_KRB5_KT_FREE_ENTRY)
 494         return krb5_kt_free_entry(context, kt_entry);
 495 #elif defined(HAVE_KRB5_FREE_KEYTAB_ENTRY_CONTENTS)
 496         return krb5_free_keytab_entry_contents(context, kt_entry);
 497 #else
 498 #error UNKNOWN_KT_FREE_FUNCTION
 499 #endif
 500 }
 501
 502 #else /* HAVE_KRB5 */
 503  /* this saves a few linking headaches */
 504 int cli_krb5_get_ticket(const char *principal, time_t time_offset,
 505                         DATA_BLOB *ticket, DATA_BLOB *session_key_krb5)
 506 {
 507          DEBUG(0,("NO KERBEROS SUPPORT\n"));
 508          return 1;
 509 }
 510
 511 #endif