source4/libcli/auth/gensec_krb5.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Kerberos backend for GENSEC
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004
   7    Copyright (C) Andrew Tridgell 2001
   8    Copyright (C) Luke Howard 2002-2003
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program; if not, write to the Free Software
  23    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  24 */
  25
  26 #include "includes.h"
  27 #include "system/kerberos.h"
  28 #include "system/time.h"
  29 #include "libcli/auth/kerberos.h"
  30 #include "librpc/gen_ndr/ndr_krb5pac.h"
  31 #include "auth/auth.h"
  32
  33 #undef DBGC_CLASS
  34 #define DBGC_CLASS DBGC_AUTH
  35
  36 enum GENSEC_KRB5_STATE {
  37         GENSEC_KRB5_SERVER_START,
  38         GENSEC_KRB5_CLIENT_START,
  39         GENSEC_KRB5_CLIENT_MUTUAL_AUTH,
  40         GENSEC_KRB5_DONE
  41 };
  42
  43 struct gensec_krb5_state {
  44         DATA_BLOB session_key;
  45         DATA_BLOB pac;
  46         enum GENSEC_KRB5_STATE state_position;
  47         krb5_context krb5_context;
  48         krb5_auth_context krb5_auth_context;
  49         krb5_ccache krb5_ccache;
  50         krb5_data ticket;
  51         krb5_keyblock krb5_keyblock;
  52         char *peer_principal;
  53 };
  54
  55 #ifdef KRB5_DO_VERIFY_PAC
  56 static NTSTATUS gensec_krb5_pac_checksum(DATA_BLOB pac_data,
  57                                             struct PAC_SIGNATURE_DATA *sig,
  58                                             struct gensec_krb5_state *gensec_krb5_state,
  59                                             uint32 keyusage)
  60 {
  61         krb5_error_code ret;
  62         krb5_crypto crypto;
  63         Checksum cksum;
  64         int i;
  65
  66         cksum.cksumtype         = (CKSUMTYPE)sig->type;
  67         cksum.checksum.length   = sizeof(sig->signature);
  68         cksum.checksum.data     = sig->signature;
  69
  70
  71         ret = krb5_crypto_init(gensec_krb5_state->krb5_context,
  72                                 &gensec_krb5_state->krb5_keyblock,
  73                                 0,
  74                                 &crypto);
  75         if (ret) {
  76                 DEBUG(0,("krb5_crypto_init() failed\n"));
  77                 return NT_STATUS_FOOBAR;
  78         }
  79         for (i=0; i < 40; i++) {
  80                 keyusage = i;
  81                 ret = krb5_verify_checksum(gensec_krb5_state->krb5_context,
  82                                            crypto,
  83                                            keyusage,
  84                                            pac_data.data,
  85                                            pac_data.length,
  86                                            &cksum);
  87                 if (!ret) {
  88                         DEBUG(0,("PAC Verified: keyusage: %d\n", keyusage));
  89                         break;
  90                 }
  91         }
  92         krb5_crypto_destroy(gensec_krb5_state->krb5_context, crypto);
  93
  94         if (ret) {
  95                 DEBUG(0,("NOT verifying PAC checksums yet!\n"));
  96                 //return NT_STATUS_LOGON_FAILURE;
  97         } else {
  98                 DEBUG(0,("PAC checksums verified!\n"));
  99         }
 100
 101         return NT_STATUS_OK;
 102 }
 103 #endif
 104
 105 static NTSTATUS gensec_krb5_decode_pac(TALLOC_CTX *mem_ctx,
 106                                 struct PAC_LOGON_INFO **logon_info_out,
 107                                 DATA_BLOB blob,
 108                                 struct gensec_krb5_state *gensec_krb5_state)
 109 {
 110         NTSTATUS status;
 111         struct PAC_SIGNATURE_DATA srv_sig;
 112         struct PAC_SIGNATURE_DATA *srv_sig_ptr;
 113         struct PAC_SIGNATURE_DATA kdc_sig;
 114         struct PAC_SIGNATURE_DATA *kdc_sig_ptr;
 115         struct PAC_LOGON_INFO *logon_info = NULL;
 116         struct PAC_DATA pac_data;
 117 #ifdef KRB5_DO_VERIFY_PAC
 118         DATA_BLOB tmp_blob = data_blob(NULL, 0);
 119 #endif
 120         int i;
 121
 122         status = ndr_pull_struct_blob(&blob, mem_ctx, &pac_data,
 123                                         (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA);
 124         if (!NT_STATUS_IS_OK(status)) {
 125                 DEBUG(0,("can't parse the PAC\n"));
 126                 return status;
 127         }
 128         NDR_PRINT_DEBUG(PAC_DATA, &pac_data);
 129
 130         if (pac_data.num_buffers < 3) {
 131                 /* we need logon_ingo, service_key and kdc_key */
 132                 DEBUG(0,("less than 3 PAC buffers\n"));
 133                 return NT_STATUS_FOOBAR;
 134         }
 135
 136         for (i=0; i < pac_data.num_buffers; i++) {
 137                 switch (pac_data.buffers[i].type) {
 138                         case PAC_TYPE_LOGON_INFO:
 139                                 if (!pac_data.buffers[i].info) {
 140                                         break;
 141                                 }
 142                                 logon_info = &pac_data.buffers[i].info->logon_info;
 143                                 break;
 144                         case PAC_TYPE_SRV_CHECKSUM:
 145                                 if (!pac_data.buffers[i].info) {
 146                                         break;
 147                                 }
 148                                 srv_sig_ptr = &pac_data.buffers[i].info->srv_cksum;
 149                                 srv_sig = pac_data.buffers[i].info->srv_cksum;
 150                                 break;
 151                         case PAC_TYPE_KDC_CHECKSUM:
 152                                 if (!pac_data.buffers[i].info) {
 153                                         break;
 154                                 }
 155                                 kdc_sig_ptr = &pac_data.buffers[i].info->kdc_cksum;
 156                                 kdc_sig = pac_data.buffers[i].info->kdc_cksum;
 157                                 break;
 158                         case PAC_TYPE_UNKNOWN_10:
 159                                 break;
 160                         default:
 161                                 break;
 162                 }
 163         }
 164
 165         if (!logon_info) {
 166                 DEBUG(0,("PAC no logon_info\n"));
 167                 return NT_STATUS_FOOBAR;
 168         }
 169
 170         if (!srv_sig_ptr) {
 171                 DEBUG(0,("PAC no srv_key\n"));
 172                 return NT_STATUS_FOOBAR;
 173         }
 174
 175         if (!kdc_sig_ptr) {
 176                 DEBUG(0,("PAC no kdc_key\n"));
 177                 return NT_STATUS_FOOBAR;
 178         }
 179 #ifdef KRB5_DO_VERIFY_PAC
 180         /* clear the kdc_key */
 181 /*      memset((void *)kdc_sig_ptr , '\0', sizeof(*kdc_sig_ptr));*/
 182
 183         status = ndr_push_struct_blob(&tmp_blob, mem_ctx, &pac_data,
 184                                               (ndr_push_flags_fn_t)ndr_push_PAC_DATA);
 185         if (!NT_STATUS_IS_OK(status)) {
 186                 return status;
 187         }
 188         status = ndr_pull_struct_blob(&tmp_blob, mem_ctx, &pac_data,
 189                                         (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA);
 190         if (!NT_STATUS_IS_OK(status)) {
 191                 DEBUG(0,("can't parse the PAC\n"));
 192                 return status;
 193         }
 194         /*NDR_PRINT_DEBUG(PAC_DATA, &pac_data);*/
 195
 196         /* verify by kdc_key */
 197         status = gensec_krb5_pac_checksum(tmp_blob, &kdc_sig, gensec_krb5_state, 0);
 198
 199         if (!NT_STATUS_IS_OK(status)) {
 200                 return status;
 201         }
 202
 203         /* clear the service_key */
 204 /*      memset((void *)srv_sig_ptr , '\0', sizeof(*srv_sig_ptr));*/
 205
 206         status = ndr_push_struct_blob(&tmp_blob, mem_ctx, &pac_data,
 207                                               (ndr_push_flags_fn_t)ndr_push_PAC_DATA);
 208         if (!NT_STATUS_IS_OK(status)) {
 209                 return status;
 210         }
 211         status = ndr_pull_struct_blob(&tmp_blob, mem_ctx, &pac_data,
 212                                         (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA);
 213         if (!NT_STATUS_IS_OK(status)) {
 214                 DEBUG(0,("can't parse the PAC\n"));
 215                 return status;
 216         }
 217         NDR_PRINT_DEBUG(PAC_DATA, &pac_data);
 218
 219         /* verify by servie_key */
 220         status = gensec_krb5_pac_checksum(tmp_blob, &srv_sig, gensec_krb5_state, 0);
 221
 222         if (!NT_STATUS_IS_OK(status)) {
 223                 return status;
 224         }
 225 #endif
 226         DEBUG(0,("account_name: %s [%s]\n",logon_info->info3.base.account_name.string, logon_info->info3.base.full_name.string));
 227         *logon_info_out = logon_info;
 228
 229         return status;
 230 }
 231
 232 static void gensec_krb5_end(struct gensec_security *gensec_security)
 233 {
 234         struct gensec_krb5_state *gensec_krb5_state = gensec_security->private_data;
 235
 236         if (gensec_krb5_state->ticket.length) {
 237         /* Hmm, early heimdal dooesn't have this - correct call would be krb5_data_free */
 238 #ifdef HAVE_KRB5_FREE_DATA_CONTENTS
 239                 krb5_free_data_contents(gensec_krb5_state->krb5_context, &gensec_krb5_state->ticket);
 240 #endif
 241         }
 242         if (gensec_krb5_state->krb5_ccache) {
 243                 /* current heimdal - 0.6.3, which we need anyway, fixes segfaults here */
 244                 krb5_cc_close(gensec_krb5_state->krb5_context, gensec_krb5_state->krb5_ccache);
 245         }
 246
 247         krb5_free_keyblock_contents(gensec_krb5_state->krb5_context,
 248                                     &gensec_krb5_state->krb5_keyblock);
 249
 250         if (gensec_krb5_state->krb5_auth_context) {
 251                 krb5_auth_con_free(gensec_krb5_state->krb5_context,
 252                                    gensec_krb5_state->krb5_auth_context);
 253         }
 254
 255         if (gensec_krb5_state->krb5_context) {
 256                 krb5_free_context(gensec_krb5_state->krb5_context);
 257         }
 258
 259         talloc_free(gensec_krb5_state);
 260         gensec_security->private_data = NULL;
 261 }
 262
 263
 264 static NTSTATUS gensec_krb5_start(struct gensec_security *gensec_security)
 265 {
 266         struct gensec_krb5_state *gensec_krb5_state;
 267         krb5_error_code ret = 0;
 268
 269         gensec_krb5_state = talloc_p(gensec_security, struct gensec_krb5_state);
 270         if (!gensec_krb5_state) {
 271                 return NT_STATUS_NO_MEMORY;
 272         }
 273
 274         gensec_security->private_data = gensec_krb5_state;
 275
 276         initialize_krb5_error_table();
 277         gensec_krb5_state->krb5_context = NULL;
 278         gensec_krb5_state->krb5_auth_context = NULL;
 279         gensec_krb5_state->krb5_ccache = NULL;
 280         ZERO_STRUCT(gensec_krb5_state->ticket);
 281         ZERO_STRUCT(gensec_krb5_state->krb5_keyblock);
 282         gensec_krb5_state->session_key = data_blob(NULL, 0);
 283         gensec_krb5_state->pac = data_blob(NULL, 0);
 284
 285         ret = krb5_init_context(&gensec_krb5_state->krb5_context);
 286         if (ret) {
 287                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n", error_message(ret)));
 288                 return NT_STATUS_INTERNAL_ERROR;
 289         }
 290
 291         if (lp_realm() && *lp_realm()) {
 292                 ret = krb5_set_default_realm(gensec_krb5_state->krb5_context, lp_realm());
 293                 if (ret) {
 294                         DEBUG(1,("gensec_krb5_start: krb5_set_default_realm failed (%s)\n", error_message(ret)));
 295                         return NT_STATUS_INTERNAL_ERROR;
 296                 }
 297         }
 298
 299         ret = krb5_auth_con_init(gensec_krb5_state->krb5_context, &gensec_krb5_state->krb5_auth_context);
 300         if (ret) {
 301                 DEBUG(1,("gensec_krb5_start: krb5_auth_con_init failed (%s)\n", error_message(ret)));
 302                 return NT_STATUS_INTERNAL_ERROR;
 303         }
 304
 305         return NT_STATUS_OK;
 306 }
 307
 308 static NTSTATUS gensec_krb5_server_start(struct gensec_security *gensec_security)
 309 {
 310         NTSTATUS nt_status;
 311         struct gensec_krb5_state *gensec_krb5_state;
 312
 313         nt_status = gensec_krb5_start(gensec_security);
 314         if (!NT_STATUS_IS_OK(nt_status)) {
 315                 return nt_status;
 316         }
 317
 318         gensec_krb5_state = gensec_security->private_data;
 319         gensec_krb5_state->state_position = GENSEC_KRB5_SERVER_START;
 320
 321         return NT_STATUS_OK;
 322 }
 323
 324 static NTSTATUS gensec_krb5_client_start(struct gensec_security *gensec_security)
 325 {
 326         struct gensec_krb5_state *gensec_krb5_state;
 327         krb5_error_code ret;
 328         NTSTATUS nt_status;
 329
 330         nt_status = gensec_krb5_start(gensec_security);
 331         if (!NT_STATUS_IS_OK(nt_status)) {
 332                 return nt_status;
 333         }
 334
 335         gensec_krb5_state = gensec_security->private_data;
 336         gensec_krb5_state->state_position = GENSEC_KRB5_CLIENT_START;
 337
 338         /* TODO: This is effecivly a static/global variable... */
 339         ret = krb5_cc_default(gensec_krb5_state->krb5_context, &gensec_krb5_state->krb5_ccache);
 340         if (ret) {
 341                 DEBUG(1,("krb5_cc_default failed (%s)\n",
 342                          error_message(ret)));
 343                 return NT_STATUS_INTERNAL_ERROR;
 344         }
 345
 346         while (1) {
 347                 if (gensec_security->target.principal) {
 348                         DEBUG(5, ("Finding ticket for target [%s]\n", gensec_security->target.principal));
 349                         ret = ads_krb5_mk_req(gensec_krb5_state->krb5_context,
 350                                               &gensec_krb5_state->krb5_auth_context,
 351                                               AP_OPTS_USE_SUBKEY | AP_OPTS_MUTUAL_REQUIRED,
 352                                               gensec_security->target.principal,
 353                                               gensec_krb5_state->krb5_ccache,
 354                                               &gensec_krb5_state->ticket);
 355                 } else {
 356                         krb5_data in_data;
 357                         const char *hostname = gensec_get_target_hostname(gensec_security);
 358                         if (!hostname) {
 359                                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 360                                 return NT_STATUS_ACCESS_DENIED;
 361                         }
 362
 363                         in_data.length = 0;
 364
 365                         ret = krb5_mk_req(gensec_krb5_state->krb5_context,
 366                                           &gensec_krb5_state->krb5_auth_context,
 367                                           AP_OPTS_USE_SUBKEY | AP_OPTS_MUTUAL_REQUIRED,
 368                                           gensec_get_target_service(gensec_security),
 369                                           hostname,
 370                                           &in_data, gensec_krb5_state->krb5_ccache,
 371                                           &gensec_krb5_state->ticket);
 372
 373                 }
 374                 switch (ret) {
 375                 case 0:
 376                         return NT_STATUS_OK;
 377                 case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 378                         DEBUG(3, ("Server is not registered with our KDC: %s\n",
 379                                   error_message(ret)));
 380                         return NT_STATUS_ACCESS_DENIED;
 381                 case KRB5KDC_ERR_PREAUTH_FAILED:
 382                 case KRB5KRB_AP_ERR_TKT_EXPIRED:
 383                 case KRB5_CC_END:
 384                 {
 385                         DEBUG(3, ("kerberos (mk_req) failed: %s\n",
 386                                   error_message(ret)));
 387                         /* fall down to remaining code */
 388                 }
 389                 /* just don't print a message for these really ordinary messages */
 390                 case KRB5_FCC_NOFILE:
 391                 case KRB5_CC_NOTFOUND:
 392                 case ENOENT:
 393                 {
 394                         char *password;
 395                         time_t kdc_time = 0;
 396                         nt_status = gensec_get_password(gensec_security,
 397                                                         gensec_security,
 398                                                         &password);
 399                         if (!NT_STATUS_IS_OK(nt_status)) {
 400                                 return nt_status;
 401                         }
 402
 403                         ret = kerberos_kinit_password_cc(gensec_krb5_state->krb5_context, gensec_krb5_state->krb5_ccache,
 404                                                          gensec_get_client_principal(gensec_security, gensec_security),
 405                                                          password, NULL, &kdc_time);
 406
 407                         /* cope with ticket being in the future due to clock skew */
 408                         if ((unsigned)kdc_time > time(NULL)) {
 409                                 time_t t = time(NULL);
 410                                 int time_offset =(unsigned)kdc_time-t;
 411                                 DEBUG(4,("Advancing clock by %d seconds to cope with clock skew\n", time_offset));
 412                                 krb5_set_real_time(gensec_krb5_state->krb5_context, t + time_offset + 1, 0);
 413                         }
 414
 415                         if (ret) {
 416                                 DEBUG(1,("kinit failed (%s)\n",
 417                                          error_message(ret)));
 418                                 return NT_STATUS_WRONG_PASSWORD;
 419                         }
 420                         break;
 421                 }
 422                 default:
 423                         DEBUG(0, ("kerberos: %s\n",
 424                                   error_message(ret)));
 425                         return NT_STATUS_UNSUCCESSFUL;
 426                 }
 427         }
 428 }
 429
 430
 431 /**
 432  * Next state function for the Krb5 GENSEC mechanism
 433  *
 434  * @param gensec_krb5_state KRB5 State
 435  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 436  * @param in The request, as a DATA_BLOB
 437  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 438  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 439  *                or NT_STATUS_OK if the user is authenticated.
 440  */
 441
 442 static NTSTATUS gensec_krb5_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx,
 443                                       const DATA_BLOB in, DATA_BLOB *out)
 444 {
 445         struct gensec_krb5_state *gensec_krb5_state = gensec_security->private_data;
 446         krb5_error_code ret = 0;
 447         DATA_BLOB pac;
 448         NTSTATUS nt_status;
 449
 450         switch (gensec_krb5_state->state_position) {
 451         case GENSEC_KRB5_CLIENT_START:
 452         {
 453                 if (ret) {
 454                         DEBUG(1,("ads_krb5_mk_req (request ticket) failed (%s)\n",
 455                                  error_message(ret)));
 456                         nt_status = NT_STATUS_LOGON_FAILURE;
 457                 } else {
 458                         DATA_BLOB unwrapped_out;
 459
 460 #ifndef GENSEC_SEND_UNWRAPPED_KRB5 /* This should be a switch for the torture code to set */
 461                         unwrapped_out = data_blob_talloc(out_mem_ctx, gensec_krb5_state->ticket.data, gensec_krb5_state->ticket.length);
 462
 463                         /* wrap that up in a nice GSS-API wrapping */
 464                         *out = gensec_gssapi_gen_krb5_wrap(out_mem_ctx, &unwrapped_out, TOK_ID_KRB_AP_REQ);
 465 #else
 466                         *out = data_blob_talloc(out_mem_ctx, gensec_krb5_state->ticket.data, gensec_krb5_state->ticket.length);
 467 #endif
 468                         gensec_krb5_state->state_position = GENSEC_KRB5_CLIENT_MUTUAL_AUTH;
 469                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 470                 }
 471
 472                 return nt_status;
 473         }
 474
 475         case GENSEC_KRB5_CLIENT_MUTUAL_AUTH:
 476         {
 477                 krb5_data inbuf;
 478                 krb5_ap_rep_enc_part *repl = NULL;
 479                 uint8 tok_id[2];
 480                 DATA_BLOB unwrapped_in;
 481
 482                 if (!gensec_gssapi_parse_krb5_wrap(out_mem_ctx, &in, &unwrapped_in, tok_id)) {
 483                         DEBUG(1,("gensec_gssapi_parse_krb5_wrap(mutual authentication) failed to parse\n"));
 484                         dump_data_pw("Mutual authentication message:\n", in.data, in.length);
 485                         return NT_STATUS_INVALID_PARAMETER;
 486                 }
 487                 /* TODO: check the tok_id */
 488
 489                 inbuf.data = unwrapped_in.data;
 490                 inbuf.length = unwrapped_in.length;
 491                 ret = krb5_rd_rep(gensec_krb5_state->krb5_context,
 492                                   gensec_krb5_state->krb5_auth_context,
 493                                   &inbuf, &repl);
 494                 if (ret) {
 495                         DEBUG(1,("krb5_rd_rep (mutual authentication) failed (%s)\n",
 496                                  error_message(ret)));
 497                         dump_data_pw("Mutual authentication message:\n", inbuf.data, inbuf.length);
 498                         nt_status = NT_STATUS_ACCESS_DENIED;
 499                 } else {
 500                         *out = data_blob(NULL, 0);
 501                         nt_status = NT_STATUS_OK;
 502                         gensec_krb5_state->state_position = GENSEC_KRB5_DONE;
 503                 }
 504                 if (repl) {
 505                         krb5_free_ap_rep_enc_part(gensec_krb5_state->krb5_context, repl);
 506                 }
 507                 return nt_status;
 508         }
 509
 510         case GENSEC_KRB5_SERVER_START:
 511         {
 512                 char *principal;
 513                 DATA_BLOB unwrapped_in;
 514                 DATA_BLOB unwrapped_out = data_blob(NULL, 0);
 515                 uint8 tok_id[2];
 516
 517                 if (!in.data) {
 518                         *out = unwrapped_out;
 519                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 520                 }
 521
 522                 /* Parse the GSSAPI wrapping, if it's there... (win2k3 allows it to be omited) */
 523                 if (!gensec_gssapi_parse_krb5_wrap(out_mem_ctx, &in, &unwrapped_in, tok_id)) {
 524                         nt_status = ads_verify_ticket(out_mem_ctx,
 525                                                       gensec_krb5_state->krb5_context,
 526                                                       gensec_krb5_state->krb5_auth_context,
 527                                                       lp_realm(), &in,
 528                                                       &principal, &pac, &unwrapped_out,
 529                                                       &gensec_krb5_state->krb5_keyblock);
 530                 } else {
 531                         /* TODO: check the tok_id */
 532                         nt_status = ads_verify_ticket(out_mem_ctx,
 533                                                       gensec_krb5_state->krb5_context,
 534                                                       gensec_krb5_state->krb5_auth_context,
 535                                                       lp_realm(), &unwrapped_in,
 536                                                       &principal, &pac, &unwrapped_out,
 537                                                       &gensec_krb5_state->krb5_keyblock);
 538                 }
 539
 540                 if (!NT_STATUS_IS_OK(nt_status)) {
 541                         return nt_status;
 542                 }
 543
 544                 if (pac.data) {
 545                         gensec_krb5_state->pac = data_blob_talloc_reference(gensec_krb5_state, &pac);
 546                 }
 547
 548                 if (NT_STATUS_IS_OK(nt_status)) {
 549                         gensec_krb5_state->state_position = GENSEC_KRB5_DONE;
 550                         /* wrap that up in a nice GSS-API wrapping */
 551 #ifndef GENSEC_SEND_UNWRAPPED_KRB5
 552                         *out = gensec_gssapi_gen_krb5_wrap(out_mem_ctx, &unwrapped_out, TOK_ID_KRB_AP_REP);
 553 #else
 554                         *out = unwrapped_out;
 555 #endif
 556                         gensec_krb5_state->peer_principal = talloc_steal(gensec_krb5_state, principal);
 557                 }
 558                 return nt_status;
 559         }
 560         case GENSEC_KRB5_DONE:
 561                 return NT_STATUS_OK;
 562         }
 563
 564         return NT_STATUS_INVALID_PARAMETER;
 565 }
 566
 567 static NTSTATUS gensec_krb5_session_key(struct gensec_security *gensec_security,
 568                                            DATA_BLOB *session_key)
 569 {
 570         struct gensec_krb5_state *gensec_krb5_state = gensec_security->private_data;
 571         krb5_context context = gensec_krb5_state->krb5_context;
 572         krb5_auth_context auth_context = gensec_krb5_state->krb5_auth_context;
 573         krb5_keyblock *skey;
 574         krb5_error_code err;
 575
 576         if (gensec_krb5_state->session_key.data) {
 577                 *session_key = gensec_krb5_state->session_key;
 578                 return NT_STATUS_OK;
 579         }
 580
 581         switch (gensec_security->gensec_role) {
 582         case GENSEC_CLIENT:
 583                 err = krb5_auth_con_getlocalsubkey(context, auth_context, &skey);
 584                 break;
 585         case GENSEC_SERVER:
 586                 err = krb5_auth_con_getremotesubkey(context, auth_context, &skey);
 587                 break;
 588         }
 589         if (err == 0 && skey != NULL) {
 590                 DEBUG(10, ("Got KRB5 session key of length %d\n",  KRB5_KEY_LENGTH(skey)));
 591                 gensec_krb5_state->session_key = data_blob_talloc(gensec_krb5_state,
 592                                                 KRB5_KEY_DATA(skey), KRB5_KEY_LENGTH(skey));
 593                 *session_key = gensec_krb5_state->session_key;
 594                 dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
 595
 596                 krb5_free_keyblock(context, skey);
 597                 return NT_STATUS_OK;
 598         } else {
 599                 DEBUG(10, ("KRB5 error getting session key %d\n", err));
 600                 return NT_STATUS_NO_USER_SESSION_KEY;
 601         }
 602 }
 603
 604 static NTSTATUS gensec_krb5_session_info(struct gensec_security *gensec_security,
 605                                      struct auth_session_info **session_info_out)
 606 {
 607         NTSTATUS nt_status;
 608         struct gensec_krb5_state *gensec_krb5_state = gensec_security->private_data;
 609         struct auth_serversupplied_info *server_info = NULL;
 610         struct auth_session_info *session_info = NULL;
 611         struct PAC_LOGON_INFO *logon_info;
 612         char *p;
 613         char *principal;
 614         const char *username;
 615         const char *realm;
 616
 617         *session_info_out = NULL;
 618
 619         principal = talloc_strdup(gensec_krb5_state, gensec_krb5_state->peer_principal);
 620         p = strchr(principal, '@');
 621         if (p) {
 622                 *p = '\0';
 623         }
 624         p++;
 625         username = principal;
 626         realm = p;
 627
 628         /* decode and verify the pac */
 629         nt_status = gensec_krb5_decode_pac(gensec_krb5_state, &logon_info, gensec_krb5_state->pac,
 630                                            gensec_krb5_state);
 631
 632         /* IF we have the PAC - otherwise we need to get this
 633          * data from elsewere - local ldb, or (TODO) lookup of some
 634          * kind...
 635          *
 636          * when heimdal can generate the PAC, we should fail if there's
 637          * no PAC present
 638          */
 639
 640         if (NT_STATUS_IS_OK(nt_status)) {
 641                 union netr_Validation validation;
 642                 validation.sam3 = &logon_info->info3;
 643                 nt_status = make_server_info_netlogon_validation(gensec_krb5_state,
 644                                                                  username,
 645                                                                  &server_info,
 646                                                                  3,
 647                                                                  &validation);
 648                 if (!NT_STATUS_IS_OK(nt_status)) {
 649                         return nt_status;
 650                 }
 651         } else {
 652                 nt_status = sam_get_server_info(username, realm, gensec_krb5_state, &server_info);
 653                 if (!NT_STATUS_IS_OK(nt_status)) {
 654                         return nt_status;
 655                 }
 656         }
 657
 658         /* references the server_info into the session_info */
 659         nt_status = make_session_info(gensec_krb5_state, server_info, &session_info);
 660         talloc_free(server_info);
 661         if (!NT_STATUS_IS_OK(nt_status)) {
 662                 return nt_status;
 663         }
 664
 665         talloc_free(principal);
 666
 667         nt_status = gensec_krb5_session_key(gensec_security, &session_info->session_key);
 668
 669         session_info->workstation = NULL;
 670
 671         *session_info_out = session_info;
 672
 673         return nt_status;
 674 }
 675
 676
 677 static const struct gensec_security_ops gensec_krb5_security_ops = {
 678         .name           = "krb5",
 679         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
 680         .oid            = GENSEC_OID_KERBEROS5,
 681         .client_start   = gensec_krb5_client_start,
 682         .server_start   = gensec_krb5_server_start,
 683         .update         = gensec_krb5_update,
 684         .session_key    = gensec_krb5_session_key,
 685         .session_info   = gensec_krb5_session_info,
 686         .end            = gensec_krb5_end
 687 };
 688
 689 static const struct gensec_security_ops gensec_ms_krb5_security_ops = {
 690         .name           = "ms_krb5",
 691         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
 692         .oid            = GENSEC_OID_KERBEROS5_OLD,
 693         .client_start   = gensec_krb5_client_start,
 694         .server_start   = gensec_krb5_server_start,
 695         .update         = gensec_krb5_update,
 696         .session_key    = gensec_krb5_session_key,
 697         .session_info   = gensec_krb5_session_info,
 698         .end            = gensec_krb5_end
 699 };
 700
 701
 702 NTSTATUS gensec_krb5_init(void)
 703 {
 704         NTSTATUS ret;
 705
 706         ret = gensec_register(&gensec_krb5_security_ops);
 707         if (!NT_STATUS_IS_OK(ret)) {
 708                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 709                         gensec_krb5_security_ops.name));
 710                 return ret;
 711         }
 712
 713         ret = gensec_register(&gensec_ms_krb5_security_ops);
 714         if (!NT_STATUS_IS_OK(ret)) {
 715                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 716                         gensec_krb5_security_ops.name));
 717                 return ret;
 718         }
 719
 720         return ret;
 721 }