source4/auth/gensec/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    Copyright (C) Stefan Metzmacher 2004-2005
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 2 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21
  22    You should have received a copy of the GNU General Public License
  23    along with this program; if not, write to the Free Software
  24    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25 */
  26
  27 #include "includes.h"
  28 #include "system/kerberos.h"
  29 #include "system/time.h"
  30 #include "system/network.h"
  31 #include "auth/kerberos/kerberos.h"
  32 #include "librpc/gen_ndr/ndr_krb5pac.h"
  33 #include "auth/auth.h"
  34
  35 enum GENSEC_KRB5_STATE {
  36         GENSEC_KRB5_SERVER_START,
  37         GENSEC_KRB5_CLIENT_START,
  38         GENSEC_KRB5_CLIENT_MUTUAL_AUTH,
  39         GENSEC_KRB5_DONE
  40 };
  41
  42 struct gensec_krb5_state {
  43         DATA_BLOB session_key;
  44         DATA_BLOB pac;
  45         enum GENSEC_KRB5_STATE state_position;
  46         struct smb_krb5_context *smb_krb5_context;
  47         krb5_auth_context auth_context;
  48         krb5_ccache ccache;
  49         krb5_data ticket;
  50         krb5_keyblock keyblock;
  51         char *peer_principal;
  52 };
  53
  54 #ifdef KRB5_DO_VERIFY_PAC
  55 static NTSTATUS gensec_krb5_pac_checksum(DATA_BLOB pac_data,
  56                                          struct PAC_SIGNATURE_DATA *sig,
  57                                          struct gensec_krb5_state *gensec_krb5_state,
  58                                          uint32 keyusage)
  59 {
  60         krb5_error_code ret;
  61         krb5_crypto crypto;
  62         Checksum cksum;
  63         int i;
  64
  65         cksum.cksumtype         = (CKSUMTYPE)sig->type;
  66         cksum.checksum.length   = sizeof(sig->signature);
  67         cksum.checksum.data     = sig->signature;
  68
  69
  70         ret = krb5_crypto_init(gensec_krb5_state->smb_krb5_context->krb5_context,
  71                                 &gensec_krb5_state->keyblock,
  72                                 0,
  73                                 &crypto);
  74         if (ret) {
  75                 DEBUG(0,("krb5_crypto_init() failed\n"));
  76                 return NT_STATUS_FOOBAR;
  77         }
  78         for (i=0; i < 40; i++) {
  79                 keyusage = i;
  80                 ret = krb5_verify_checksum(gensec_krb5_state->smb_krb5_context->krb5_context,
  81                                            crypto,
  82                                            keyusage,
  83                                            pac_data.data,
  84                                            pac_data.length,
  85                                            &cksum);
  86                 if (!ret) {
  87                         DEBUG(0,("PAC Verified: keyusage: %d\n", keyusage));
  88                         break;
  89                 }
  90         }
  91         krb5_crypto_destroy(gensec_krb5_state->smb_krb5_context->krb5_context, crypto);
  92
  93         if (ret) {
  94                 DEBUG(0,("NOT verifying PAC checksums yet!\n"));
  95                 //return NT_STATUS_LOGON_FAILURE;
  96         } else {
  97                 DEBUG(0,("PAC checksums verified!\n"));
  98         }
  99
 100         return NT_STATUS_OK;
 101 }
 102 #endif
 103
 104 static NTSTATUS gensec_krb5_decode_pac(TALLOC_CTX *mem_ctx,
 105                                 struct PAC_LOGON_INFO **logon_info_out,
 106                                 DATA_BLOB blob,
 107                                 struct gensec_krb5_state *gensec_krb5_state)
 108 {
 109         NTSTATUS status;
 110         struct PAC_SIGNATURE_DATA srv_sig;
 111         struct PAC_SIGNATURE_DATA *srv_sig_ptr;
 112         struct PAC_SIGNATURE_DATA kdc_sig;
 113         struct PAC_SIGNATURE_DATA *kdc_sig_ptr;
 114         struct PAC_LOGON_INFO *logon_info = NULL;
 115         struct PAC_DATA pac_data;
 116 #ifdef KRB5_DO_VERIFY_PAC
 117         DATA_BLOB tmp_blob = data_blob(NULL, 0);
 118 #endif
 119         int i;
 120
 121         status = ndr_pull_struct_blob(&blob, mem_ctx, &pac_data,
 122                                         (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA);
 123         if (!NT_STATUS_IS_OK(status)) {
 124                 DEBUG(0,("can't parse the PAC\n"));
 125                 return status;
 126         }
 127         NDR_PRINT_DEBUG(PAC_DATA, &pac_data);
 128
 129         if (pac_data.num_buffers < 3) {
 130                 /* we need logon_ingo, service_key and kdc_key */
 131                 DEBUG(0,("less than 3 PAC buffers\n"));
 132                 return NT_STATUS_FOOBAR;
 133         }
 134
 135         for (i=0; i < pac_data.num_buffers; i++) {
 136                 switch (pac_data.buffers[i].type) {
 137                         case PAC_TYPE_LOGON_INFO:
 138                                 if (!pac_data.buffers[i].info) {
 139                                         break;
 140                                 }
 141                                 logon_info = &pac_data.buffers[i].info->logon_info;
 142                                 break;
 143                         case PAC_TYPE_SRV_CHECKSUM:
 144                                 if (!pac_data.buffers[i].info) {
 145                                         break;
 146                                 }
 147                                 srv_sig_ptr = &pac_data.buffers[i].info->srv_cksum;
 148                                 srv_sig = pac_data.buffers[i].info->srv_cksum;
 149                                 break;
 150                         case PAC_TYPE_KDC_CHECKSUM:
 151                                 if (!pac_data.buffers[i].info) {
 152                                         break;
 153                                 }
 154                                 kdc_sig_ptr = &pac_data.buffers[i].info->kdc_cksum;
 155                                 kdc_sig = pac_data.buffers[i].info->kdc_cksum;
 156                                 break;
 157                         case PAC_TYPE_UNKNOWN_10:
 158                                 break;
 159                         default:
 160                                 break;
 161                 }
 162         }
 163
 164         if (!logon_info) {
 165                 DEBUG(0,("PAC no logon_info\n"));
 166                 return NT_STATUS_FOOBAR;
 167         }
 168
 169         if (!srv_sig_ptr) {
 170                 DEBUG(0,("PAC no srv_key\n"));
 171                 return NT_STATUS_FOOBAR;
 172         }
 173
 174         if (!kdc_sig_ptr) {
 175                 DEBUG(0,("PAC no kdc_key\n"));
 176                 return NT_STATUS_FOOBAR;
 177         }
 178 #ifdef KRB5_DO_VERIFY_PAC
 179         /* clear the kdc_key */
 180 /*      memset((void *)kdc_sig_ptr , '\0', sizeof(*kdc_sig_ptr));*/
 181
 182         status = ndr_push_struct_blob(&tmp_blob, mem_ctx, &pac_data,
 183                                               (ndr_push_flags_fn_t)ndr_push_PAC_DATA);
 184         if (!NT_STATUS_IS_OK(status)) {
 185                 return status;
 186         }
 187         status = ndr_pull_struct_blob(&tmp_blob, mem_ctx, &pac_data,
 188                                         (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA);
 189         if (!NT_STATUS_IS_OK(status)) {
 190                 DEBUG(0,("can't parse the PAC\n"));
 191                 return status;
 192         }
 193         /*NDR_PRINT_DEBUG(PAC_DATA, &pac_data);*/
 194
 195         /* verify by kdc_key */
 196         status = gensec_krb5_pac_checksum(tmp_blob, &kdc_sig, gensec_krb5_state, 0);
 197
 198         if (!NT_STATUS_IS_OK(status)) {
 199                 return status;
 200         }
 201
 202         /* clear the service_key */
 203 /*      memset((void *)srv_sig_ptr , '\0', sizeof(*srv_sig_ptr));*/
 204
 205         status = ndr_push_struct_blob(&tmp_blob, mem_ctx, &pac_data,
 206                                               (ndr_push_flags_fn_t)ndr_push_PAC_DATA);
 207         if (!NT_STATUS_IS_OK(status)) {
 208                 return status;
 209         }
 210         status = ndr_pull_struct_blob(&tmp_blob, mem_ctx, &pac_data,
 211                                         (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA);
 212         if (!NT_STATUS_IS_OK(status)) {
 213                 DEBUG(0,("can't parse the PAC\n"));
 214                 return status;
 215         }
 216         NDR_PRINT_DEBUG(PAC_DATA, &pac_data);
 217
 218         /* verify by servie_key */
 219         status = gensec_krb5_pac_checksum(tmp_blob, &srv_sig, gensec_krb5_state, 0);
 220
 221         if (!NT_STATUS_IS_OK(status)) {
 222                 return status;
 223         }
 224 #endif
 225         DEBUG(0,("account_name: %s [%s]\n",
 226                  logon_info->info3.base.account_name.string,
 227                  logon_info->info3.base.full_name.string));
 228         *logon_info_out = logon_info;
 229
 230         return status;
 231 }
 232
 233 static int gensec_krb5_destory(void *ptr)
 234 {
 235         struct gensec_krb5_state *gensec_krb5_state = ptr;
 236
 237         if (gensec_krb5_state->ticket.length) {
 238                 kerberos_free_data_contents(gensec_krb5_state->smb_krb5_context->krb5_context,
 239                                             &gensec_krb5_state->ticket);
 240         }
 241         /* ccache freed in a child destructor */
 242
 243         krb5_free_keyblock_contents(gensec_krb5_state->smb_krb5_context->krb5_context,
 244                                     &gensec_krb5_state->keyblock);
 245
 246         if (gensec_krb5_state->auth_context) {
 247                 krb5_auth_con_free(gensec_krb5_state->smb_krb5_context->krb5_context,
 248                                    gensec_krb5_state->auth_context);
 249         }
 250
 251         return 0;
 252 }
 253
 254 static NTSTATUS gensec_krb5_start(struct gensec_security *gensec_security)
 255 {
 256         struct gensec_krb5_state *gensec_krb5_state;
 257         krb5_error_code ret = 0;
 258
 259         gensec_krb5_state = talloc(gensec_security, struct gensec_krb5_state);
 260         if (!gensec_krb5_state) {
 261                 return NT_STATUS_NO_MEMORY;
 262         }
 263
 264         gensec_security->private_data = gensec_krb5_state;
 265
 266         initialize_krb5_error_table();
 267         gensec_krb5_state->auth_context = NULL;
 268         gensec_krb5_state->ccache = NULL;
 269         ZERO_STRUCT(gensec_krb5_state->ticket);
 270         ZERO_STRUCT(gensec_krb5_state->keyblock);
 271         gensec_krb5_state->session_key = data_blob(NULL, 0);
 272         gensec_krb5_state->pac = data_blob(NULL, 0);
 273
 274         talloc_set_destructor(gensec_krb5_state, gensec_krb5_destory);
 275
 276         ret = smb_krb5_init_context(gensec_krb5_state,
 277                                     &gensec_krb5_state->smb_krb5_context);
 278         if (ret) {
 279                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n",
 280                          error_message(ret)));
 281                 return NT_STATUS_INTERNAL_ERROR;
 282         }
 283
 284         ret = krb5_auth_con_init(gensec_krb5_state->smb_krb5_context->krb5_context, &gensec_krb5_state->auth_context);
 285         if (ret) {
 286                 DEBUG(1,("gensec_krb5_start: krb5_auth_con_init failed (%s)\n",
 287                          smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context,
 288                                                     ret, gensec_krb5_state)));
 289                 return NT_STATUS_INTERNAL_ERROR;
 290         }
 291
 292         return NT_STATUS_OK;
 293 }
 294
 295 static NTSTATUS gensec_krb5_server_start(struct gensec_security *gensec_security)
 296 {
 297         NTSTATUS nt_status;
 298         struct gensec_krb5_state *gensec_krb5_state;
 299
 300         nt_status = gensec_krb5_start(gensec_security);
 301         if (!NT_STATUS_IS_OK(nt_status)) {
 302                 return nt_status;
 303         }
 304
 305         gensec_krb5_state = gensec_security->private_data;
 306         gensec_krb5_state->state_position = GENSEC_KRB5_SERVER_START;
 307
 308         return NT_STATUS_OK;
 309 }
 310
 311 static NTSTATUS gensec_krb5_client_start(struct gensec_security *gensec_security)
 312 {
 313         struct gensec_krb5_state *gensec_krb5_state;
 314         krb5_error_code ret;
 315         NTSTATUS nt_status;
 316         const char *ccache_name;
 317
 318         const char *hostname = gensec_get_target_hostname(gensec_security);
 319         if (!hostname) {
 320                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 321                 return NT_STATUS_ACCESS_DENIED;
 322         }
 323
 324         nt_status = gensec_krb5_start(gensec_security);
 325         if (!NT_STATUS_IS_OK(nt_status)) {
 326                 return nt_status;
 327         }
 328
 329         gensec_krb5_state = gensec_security->private_data;
 330         gensec_krb5_state->state_position = GENSEC_KRB5_CLIENT_START;
 331
 332         /* TODO: This is effecivly a static/global variable...
 333
 334            TODO: If the user set a username, we should use an in-memory CCACHE (see below)
 335         */
 336         ret = krb5_cc_default(gensec_krb5_state->smb_krb5_context->krb5_context, &gensec_krb5_state->ccache);
 337         if (ret) {
 338                 DEBUG(1,("krb5_cc_default failed (%s)\n",
 339                          smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state)));
 340                 return NT_STATUS_INTERNAL_ERROR;
 341         }
 342
 343         while (1) {
 344                 {
 345                         krb5_data in_data;
 346                         in_data.length = 0;
 347
 348                         ret = krb5_mk_req(gensec_krb5_state->smb_krb5_context->krb5_context,
 349                                           &gensec_krb5_state->auth_context,
 350                                           AP_OPTS_USE_SUBKEY | AP_OPTS_MUTUAL_REQUIRED,
 351                                           gensec_get_target_service(gensec_security),
 352                                           hostname,
 353                                           &in_data, gensec_krb5_state->ccache,
 354                                           &gensec_krb5_state->ticket);
 355
 356                 }
 357                 switch (ret) {
 358                 case 0:
 359                         return NT_STATUS_OK;
 360                 case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 361                         DEBUG(3, ("Server [%s] is not registered with our KDC: %s\n",
 362                                   hostname, smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state)));
 363                         return NT_STATUS_ACCESS_DENIED;
 364                 case KRB5KDC_ERR_PREAUTH_FAILED:
 365                 case KRB5KRB_AP_ERR_TKT_EXPIRED:
 366                 case KRB5_CC_END:
 367                         /* Too much clock skew - we will need to kinit to re-skew the clock */
 368                 case KRB5KRB_AP_ERR_SKEW:
 369                 case KRB5_KDCREP_SKEW:
 370                 {
 371                         DEBUG(3, ("kerberos (mk_req) failed: %s\n",
 372                                   smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state)));
 373                         /* fall down to remaining code */
 374                 }
 375
 376
 377                 /* just don't print a message for these really ordinary messages */
 378                 case KRB5_FCC_NOFILE:
 379                 case KRB5_CC_NOTFOUND:
 380                 case ENOENT:
 381
 382                 nt_status = kinit_to_ccache(gensec_krb5_state,
 383                                             gensec_security->credentials,
 384                                             gensec_krb5_state->smb_krb5_context,
 385                                             &gensec_krb5_state->ccache,
 386                                             &ccache_name);
 387
 388                 if (!NT_STATUS_IS_OK(nt_status)) {
 389                         return nt_status;
 390                 }
 391                 break;
 392
 393                 default:
 394                         DEBUG(0, ("kerberos: %s\n",
 395                                   smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state)));
 396                         return NT_STATUS_UNSUCCESSFUL;
 397                 }
 398         }
 399 }
 400
 401
 402 /**
 403  * Check if the packet is one for this mechansim
 404  *
 405  * @param gensec_security GENSEC state
 406  * @param in The request, as a DATA_BLOB
 407  * @return Error, INVALID_PARAMETER if it's not a packet for us
 408  *                or NT_STATUS_OK if the packet is ok.
 409  */
 410
 411 static NTSTATUS gensec_krb5_magic(struct gensec_security *gensec_security,
 412                                   const DATA_BLOB *in)
 413 {
 414         if (gensec_gssapi_check_oid(in, GENSEC_OID_KERBEROS5)) {
 415                 return NT_STATUS_OK;
 416         } else {
 417                 return NT_STATUS_INVALID_PARAMETER;
 418         }
 419 }
 420
 421
 422 /**
 423  * Next state function for the Krb5 GENSEC mechanism
 424  *
 425  * @param gensec_krb5_state KRB5 State
 426  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 427  * @param in The request, as a DATA_BLOB
 428  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 429  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 430  *                or NT_STATUS_OK if the user is authenticated.
 431  */
 432
 433 static NTSTATUS gensec_krb5_update(struct gensec_security *gensec_security,
 434                                    TALLOC_CTX *out_mem_ctx,
 435                                    const DATA_BLOB in, DATA_BLOB *out)
 436 {
 437         struct gensec_krb5_state *gensec_krb5_state = gensec_security->private_data;
 438         krb5_error_code ret = 0;
 439         DATA_BLOB pac;
 440         NTSTATUS nt_status;
 441
 442         switch (gensec_krb5_state->state_position) {
 443         case GENSEC_KRB5_CLIENT_START:
 444         {
 445                 if (ret) {
 446                         DEBUG(1,("ads_krb5_mk_req (request ticket) failed (%s)\n",
 447                                  smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, out_mem_ctx)));
 448                         nt_status = NT_STATUS_LOGON_FAILURE;
 449                 } else {
 450                         DATA_BLOB unwrapped_out;
 451
 452 #ifndef GENSEC_SEND_UNWRAPPED_KRB5 /* This should be a switch for the torture code to set */
 453                         unwrapped_out = data_blob_talloc(out_mem_ctx, gensec_krb5_state->ticket.data, gensec_krb5_state->ticket.length);
 454
 455                         /* wrap that up in a nice GSS-API wrapping */
 456                         *out = gensec_gssapi_gen_krb5_wrap(out_mem_ctx, &unwrapped_out, TOK_ID_KRB_AP_REQ);
 457 #else
 458                         *out = data_blob_talloc(out_mem_ctx, gensec_krb5_state->ticket.data, gensec_krb5_state->ticket.length);
 459 #endif
 460                         gensec_krb5_state->state_position = GENSEC_KRB5_CLIENT_MUTUAL_AUTH;
 461                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 462                 }
 463
 464                 return nt_status;
 465         }
 466
 467         case GENSEC_KRB5_CLIENT_MUTUAL_AUTH:
 468         {
 469                 krb5_data inbuf;
 470                 krb5_ap_rep_enc_part *repl = NULL;
 471                 uint8_t tok_id[2];
 472                 DATA_BLOB unwrapped_in;
 473
 474                 if (!gensec_gssapi_parse_krb5_wrap(out_mem_ctx, &in, &unwrapped_in, tok_id)) {
 475                         DEBUG(1,("gensec_gssapi_parse_krb5_wrap(mutual authentication) failed to parse\n"));
 476                         dump_data_pw("Mutual authentication message:\n", in.data, in.length);
 477                         return NT_STATUS_INVALID_PARAMETER;
 478                 }
 479                 /* TODO: check the tok_id */
 480
 481                 inbuf.data = unwrapped_in.data;
 482                 inbuf.length = unwrapped_in.length;
 483                 ret = krb5_rd_rep(gensec_krb5_state->smb_krb5_context->krb5_context,
 484                                   gensec_krb5_state->auth_context,
 485                                   &inbuf, &repl);
 486                 if (ret) {
 487                         DEBUG(1,("krb5_rd_rep (mutual authentication) failed (%s)\n",
 488                                  smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, out_mem_ctx)));
 489                         dump_data_pw("Mutual authentication message:\n", inbuf.data, inbuf.length);
 490                         nt_status = NT_STATUS_ACCESS_DENIED;
 491                 } else {
 492                         *out = data_blob(NULL, 0);
 493                         nt_status = NT_STATUS_OK;
 494                         gensec_krb5_state->state_position = GENSEC_KRB5_DONE;
 495                 }
 496                 if (repl) {
 497                         krb5_free_ap_rep_enc_part(gensec_krb5_state->smb_krb5_context->krb5_context, repl);
 498                 }
 499                 return nt_status;
 500         }
 501
 502         case GENSEC_KRB5_SERVER_START:
 503         {
 504                 char *principal;
 505                 DATA_BLOB unwrapped_in;
 506                 DATA_BLOB unwrapped_out = data_blob(NULL, 0);
 507                 uint8_t tok_id[2];
 508
 509                 if (!in.data) {
 510                         *out = unwrapped_out;
 511                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 512                 }
 513
 514                 /* Parse the GSSAPI wrapping, if it's there... (win2k3 allows it to be omited) */
 515                 if (!gensec_gssapi_parse_krb5_wrap(out_mem_ctx, &in, &unwrapped_in, tok_id)) {
 516                         nt_status = ads_verify_ticket(out_mem_ctx,
 517                                                       gensec_krb5_state->smb_krb5_context,
 518                                                       gensec_krb5_state->auth_context,
 519                                                       lp_realm(),
 520                                                       gensec_get_target_service(gensec_security), &in,
 521                                                       &principal, &pac, &unwrapped_out,
 522                                                       &gensec_krb5_state->keyblock);
 523                 } else {
 524                         /* TODO: check the tok_id */
 525                         nt_status = ads_verify_ticket(out_mem_ctx,
 526                                                       gensec_krb5_state->smb_krb5_context,
 527                                                       gensec_krb5_state->auth_context,
 528                                                       lp_realm(),
 529                                                       gensec_get_target_service(gensec_security),
 530                                                       &unwrapped_in,
 531                                                       &principal, &pac, &unwrapped_out,
 532                                                       &gensec_krb5_state->keyblock);
 533                 }
 534
 535                 if (!NT_STATUS_IS_OK(nt_status)) {
 536                         return nt_status;
 537                 }
 538
 539                 if (pac.data) {
 540                         gensec_krb5_state->pac = data_blob_talloc_reference(gensec_krb5_state, &pac);
 541                 }
 542
 543                 if (NT_STATUS_IS_OK(nt_status)) {
 544                         gensec_krb5_state->state_position = GENSEC_KRB5_DONE;
 545                         /* wrap that up in a nice GSS-API wrapping */
 546 #ifndef GENSEC_SEND_UNWRAPPED_KRB5
 547                         *out = gensec_gssapi_gen_krb5_wrap(out_mem_ctx, &unwrapped_out, TOK_ID_KRB_AP_REP);
 548 #else
 549                         *out = unwrapped_out;
 550 #endif
 551                         gensec_krb5_state->peer_principal = talloc_steal(gensec_krb5_state, principal);
 552                 }
 553                 return nt_status;
 554         }
 555         case GENSEC_KRB5_DONE:
 556                 return NT_STATUS_OK;
 557         }
 558
 559         return NT_STATUS_INVALID_PARAMETER;
 560 }
 561
 562 static NTSTATUS gensec_krb5_session_key(struct gensec_security *gensec_security,
 563                                         DATA_BLOB *session_key)
 564 {
 565         struct gensec_krb5_state *gensec_krb5_state = gensec_security->private_data;
 566         krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context;
 567         krb5_auth_context auth_context = gensec_krb5_state->auth_context;
 568         krb5_keyblock *skey;
 569         krb5_error_code err;
 570
 571         if (gensec_krb5_state->session_key.data) {
 572                 *session_key = gensec_krb5_state->session_key;
 573                 return NT_STATUS_OK;
 574         }
 575
 576         switch (gensec_security->gensec_role) {
 577         case GENSEC_CLIENT:
 578                 err = krb5_auth_con_getlocalsubkey(context, auth_context, &skey);
 579                 break;
 580         case GENSEC_SERVER:
 581                 err = krb5_auth_con_getremotesubkey(context, auth_context, &skey);
 582                 break;
 583         }
 584         if (err == 0 && skey != NULL) {
 585                 DEBUG(10, ("Got KRB5 session key of length %d\n",  KRB5_KEY_LENGTH(skey)));
 586                 gensec_krb5_state->session_key = data_blob_talloc(gensec_krb5_state,
 587                                                 KRB5_KEY_DATA(skey), KRB5_KEY_LENGTH(skey));
 588                 *session_key = gensec_krb5_state->session_key;
 589                 dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
 590
 591                 krb5_free_keyblock(context, skey);
 592                 return NT_STATUS_OK;
 593         } else {
 594                 DEBUG(10, ("KRB5 error getting session key %d\n", err));
 595                 return NT_STATUS_NO_USER_SESSION_KEY;
 596         }
 597 }
 598
 599 static NTSTATUS gensec_krb5_session_info(struct gensec_security *gensec_security,
 600                                          struct auth_session_info **_session_info)
 601 {
 602         NTSTATUS nt_status;
 603         struct gensec_krb5_state *gensec_krb5_state = gensec_security->private_data;
 604         struct auth_serversupplied_info *server_info = NULL;
 605         struct auth_session_info *session_info = NULL;
 606         struct PAC_LOGON_INFO *logon_info;
 607         char *p;
 608         char *principal;
 609         const char *account_name;
 610         const char *realm;
 611
 612         principal = talloc_strdup(gensec_krb5_state, gensec_krb5_state->peer_principal);
 613         NT_STATUS_HAVE_NO_MEMORY(principal);
 614
 615         p = strchr(principal, '@');
 616         if (p) {
 617                 *p = '\0';
 618                 p++;
 619                 realm = p;
 620         } else {
 621                 realm = lp_realm();
 622         }
 623         account_name = principal;
 624
 625         /* decode and verify the pac */
 626         nt_status = gensec_krb5_decode_pac(gensec_krb5_state, &logon_info, gensec_krb5_state->pac,
 627                                            gensec_krb5_state);
 628
 629         /* IF we have the PAC - otherwise we need to get this
 630          * data from elsewere - local ldb, or (TODO) lookup of some
 631          * kind...
 632          *
 633          * when heimdal can generate the PAC, we should fail if there's
 634          * no PAC present
 635          */
 636
 637         if (NT_STATUS_IS_OK(nt_status)) {
 638                 union netr_Validation validation;
 639                 validation.sam3 = &logon_info->info3;
 640                 nt_status = make_server_info_netlogon_validation(gensec_krb5_state,
 641                                                                  account_name,
 642                                                                  3, &validation,
 643                                                                  &server_info);
 644                 talloc_free(principal);
 645                 NT_STATUS_NOT_OK_RETURN(nt_status);
 646         } else {
 647                 DATA_BLOB user_sess_key = data_blob(NULL, 0);
 648                 DATA_BLOB lm_sess_key = data_blob(NULL, 0);
 649                 /* TODO: should we pass the krb5 session key in here? */
 650                 nt_status = sam_get_server_info(gensec_krb5_state, account_name, realm,
 651                                                 user_sess_key, lm_sess_key,
 652                                                 &server_info);
 653                 talloc_free(principal);
 654                 NT_STATUS_NOT_OK_RETURN(nt_status);
 655         }
 656
 657         /* references the server_info into the session_info */
 658         nt_status = auth_generate_session_info(gensec_krb5_state, server_info, &session_info);
 659         talloc_free(server_info);
 660         NT_STATUS_NOT_OK_RETURN(nt_status);
 661
 662         nt_status = gensec_krb5_session_key(gensec_security, &session_info->session_key);
 663         NT_STATUS_NOT_OK_RETURN(nt_status);
 664
 665         *_session_info = session_info;
 666
 667         return NT_STATUS_OK;
 668 }
 669
 670 static BOOL gensec_krb5_have_feature(struct gensec_security *gensec_security,
 671                                      uint32_t feature)
 672 {
 673         if (feature & GENSEC_FEATURE_SESSION_KEY) {
 674                 return True;
 675         }
 676
 677         return False;
 678 }
 679
 680 static const char *gensec_krb5_oids[] = {
 681         GENSEC_OID_KERBEROS5,
 682         GENSEC_OID_KERBEROS5_OLD,
 683         NULL
 684 };
 685
 686 static const struct gensec_security_ops gensec_krb5_security_ops = {
 687         .name           = "krb5",
 688         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
 689         .oid            = gensec_krb5_oids,
 690         .client_start   = gensec_krb5_client_start,
 691         .server_start   = gensec_krb5_server_start,
 692         .magic          = gensec_krb5_magic,
 693         .update         = gensec_krb5_update,
 694         .session_key    = gensec_krb5_session_key,
 695         .session_info   = gensec_krb5_session_info,
 696         .have_feature   = gensec_krb5_have_feature,
 697         .enabled        = False
 698 };
 699
 700 NTSTATUS gensec_krb5_init(void)
 701 {
 702         NTSTATUS ret;
 703
 704         ret = gensec_register(&gensec_krb5_security_ops);
 705         if (!NT_STATUS_IS_OK(ret)) {
 706                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 707                         gensec_krb5_security_ops.name));
 708                 return ret;
 709         }
 710
 711         return ret;
 712 }