source4/auth/kerberos/kerberos_pac.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Create and parse the krb5 PAC
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005,2008
   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 3 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, see <http://www.gnu.org/licenses/>.
  24 */
  25
  26 #include "includes.h"
  27 #include "system/kerberos.h"
  28 #include "auth/auth.h"
  29 #include "auth/kerberos/kerberos.h"
  30 #include "librpc/gen_ndr/ndr_krb5pac.h"
  31 #include "lib/ldb/include/ldb.h"
  32 #include "auth/auth_sam_reply.h"
  33
  34 krb5_error_code check_pac_checksum(TALLOC_CTX *mem_ctx,
  35                                    DATA_BLOB pac_data,
  36                                    struct PAC_SIGNATURE_DATA *sig,
  37                                    krb5_context context,
  38                                    const krb5_keyblock *keyblock)
  39 {
  40         krb5_error_code ret;
  41         krb5_crypto crypto;
  42         Checksum cksum;
  43
  44         cksum.cksumtype         = (CKSUMTYPE)sig->type;
  45         cksum.checksum.length   = sig->signature.length;
  46         cksum.checksum.data     = sig->signature.data;
  47
  48         ret = krb5_crypto_init(context,
  49                                keyblock,
  50                                0,
  51                                &crypto);
  52         if (ret) {
  53                 DEBUG(0,("krb5_crypto_init() failed: %s\n",
  54                           smb_get_krb5_error_message(context, ret, mem_ctx)));
  55                 return ret;
  56         }
  57         ret = krb5_verify_checksum(context,
  58                                    crypto,
  59                                    KRB5_KU_OTHER_CKSUM,
  60                                    pac_data.data,
  61                                    pac_data.length,
  62                                    &cksum);
  63         krb5_crypto_destroy(context, crypto);
  64
  65         return ret;
  66 }
  67
  68  NTSTATUS kerberos_decode_pac(TALLOC_CTX *mem_ctx,
  69                               struct PAC_DATA **pac_data_out,
  70                               DATA_BLOB blob,
  71                               krb5_context context,
  72                               const krb5_keyblock *krbtgt_keyblock,
  73                               const krb5_keyblock *service_keyblock,
  74                               krb5_const_principal client_principal,
  75                               time_t tgs_authtime,
  76                               krb5_error_code *k5ret)
  77 {
  78         krb5_error_code ret;
  79         NTSTATUS status;
  80         enum ndr_err_code ndr_err;
  81         struct PAC_SIGNATURE_DATA *srv_sig_ptr = NULL;
  82         struct PAC_SIGNATURE_DATA *kdc_sig_ptr = NULL;
  83         struct PAC_SIGNATURE_DATA *srv_sig_wipe = NULL;
  84         struct PAC_SIGNATURE_DATA *kdc_sig_wipe = NULL;
  85         struct PAC_LOGON_INFO *logon_info = NULL;
  86         struct PAC_LOGON_NAME *logon_name = NULL;
  87         struct PAC_DATA *pac_data;
  88         struct PAC_DATA_RAW *pac_data_raw;
  89
  90         DATA_BLOB *srv_sig_blob = NULL;
  91         DATA_BLOB *kdc_sig_blob = NULL;
  92
  93         DATA_BLOB modified_pac_blob;
  94         NTTIME tgs_authtime_nttime;
  95         krb5_principal client_principal_pac;
  96         uint32_t i;
  97
  98         krb5_clear_error_message(context);
  99
 100         if (k5ret) {
 101                 *k5ret = KRB5_PARSE_MALFORMED;
 102         }
 103
 104         pac_data = talloc(mem_ctx, struct PAC_DATA);
 105         pac_data_raw = talloc(mem_ctx, struct PAC_DATA_RAW);
 106         kdc_sig_wipe = talloc(mem_ctx, struct PAC_SIGNATURE_DATA);
 107         srv_sig_wipe = talloc(mem_ctx, struct PAC_SIGNATURE_DATA);
 108         if (!pac_data_raw || !pac_data || !kdc_sig_wipe || !srv_sig_wipe) {
 109                 if (k5ret) {
 110                         *k5ret = ENOMEM;
 111                 }
 112                 return NT_STATUS_NO_MEMORY;
 113         }
 114
 115         ndr_err = ndr_pull_struct_blob(&blob, pac_data,
 116                         pac_data, (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA);
 117         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 118                 status = ndr_map_error2ntstatus(ndr_err);
 119                 DEBUG(0,("can't parse the PAC: %s\n",
 120                         nt_errstr(status)));
 121                 return status;
 122         }
 123
 124         if (pac_data->num_buffers < 4) {
 125                 /* we need logon_ingo, service_key and kdc_key */
 126                 DEBUG(0,("less than 4 PAC buffers\n"));
 127                 return NT_STATUS_INVALID_PARAMETER;
 128         }
 129
 130         ndr_err = ndr_pull_struct_blob(&blob, pac_data_raw,
 131                                        pac_data_raw,
 132                                        (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA_RAW);
 133         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 134                 status = ndr_map_error2ntstatus(ndr_err);
 135                 DEBUG(0,("can't parse the PAC: %s\n",
 136                         nt_errstr(status)));
 137                 return status;
 138         }
 139
 140         if (pac_data_raw->num_buffers < 4) {
 141                 /* we need logon_ingo, service_key and kdc_key */
 142                 DEBUG(0,("less than 4 PAC buffers\n"));
 143                 return NT_STATUS_INVALID_PARAMETER;
 144         }
 145
 146         if (pac_data->num_buffers != pac_data_raw->num_buffers) {
 147                 /* we need logon_ingo, service_key and kdc_key */
 148                 DEBUG(0,("misparse!  PAC_DATA has %d buffers while PAC_DATA_RAW has %d\n",
 149                          pac_data->num_buffers, pac_data_raw->num_buffers));
 150                 return NT_STATUS_INVALID_PARAMETER;
 151         }
 152
 153         for (i=0; i < pac_data->num_buffers; i++) {
 154                 if (pac_data->buffers[i].type != pac_data_raw->buffers[i].type) {
 155                         DEBUG(0,("misparse!  PAC_DATA buffer %d has type %d while PAC_DATA_RAW has %d\n",
 156                                  i, pac_data->buffers[i].type, pac_data->buffers[i].type));
 157                         return NT_STATUS_INVALID_PARAMETER;
 158                 }
 159                 switch (pac_data->buffers[i].type) {
 160                         case PAC_TYPE_LOGON_INFO:
 161                                 if (!pac_data->buffers[i].info) {
 162                                         break;
 163                                 }
 164                                 logon_info = pac_data->buffers[i].info->logon_info.info;
 165                                 break;
 166                         case PAC_TYPE_SRV_CHECKSUM:
 167                                 if (!pac_data->buffers[i].info) {
 168                                         break;
 169                                 }
 170                                 srv_sig_ptr = &pac_data->buffers[i].info->srv_cksum;
 171                                 srv_sig_blob = &pac_data_raw->buffers[i].info->remaining;
 172                                 break;
 173                         case PAC_TYPE_KDC_CHECKSUM:
 174                                 if (!pac_data->buffers[i].info) {
 175                                         break;
 176                                 }
 177                                 kdc_sig_ptr = &pac_data->buffers[i].info->kdc_cksum;
 178                                 kdc_sig_blob = &pac_data_raw->buffers[i].info->remaining;
 179                                 break;
 180                         case PAC_TYPE_LOGON_NAME:
 181                                 logon_name = &pac_data->buffers[i].info->logon_name;
 182                                 break;
 183                         default:
 184                                 break;
 185                 }
 186         }
 187
 188         if (!logon_info) {
 189                 DEBUG(0,("PAC no logon_info\n"));
 190                 return NT_STATUS_INVALID_PARAMETER;
 191         }
 192
 193         if (!logon_name) {
 194                 DEBUG(0,("PAC no logon_name\n"));
 195                 return NT_STATUS_INVALID_PARAMETER;
 196         }
 197
 198         if (!srv_sig_ptr || !srv_sig_blob) {
 199                 DEBUG(0,("PAC no srv_key\n"));
 200                 return NT_STATUS_INVALID_PARAMETER;
 201         }
 202
 203         if (!kdc_sig_ptr || !kdc_sig_blob) {
 204                 DEBUG(0,("PAC no kdc_key\n"));
 205                 return NT_STATUS_INVALID_PARAMETER;
 206         }
 207
 208         /* Find and zero out the signatures, as required by the signing algorithm */
 209
 210         /* We find the data blobs above, now we parse them to get at the exact portion we should zero */
 211         ndr_err = ndr_pull_struct_blob(kdc_sig_blob, kdc_sig_wipe,
 212                                        kdc_sig_wipe,
 213                                        (ndr_pull_flags_fn_t)ndr_pull_PAC_SIGNATURE_DATA);
 214         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 215                 status = ndr_map_error2ntstatus(ndr_err);
 216                 DEBUG(0,("can't parse the KDC signature: %s\n",
 217                         nt_errstr(status)));
 218                 return status;
 219         }
 220
 221         ndr_err = ndr_pull_struct_blob(srv_sig_blob, srv_sig_wipe,
 222                                        srv_sig_wipe,
 223                                        (ndr_pull_flags_fn_t)ndr_pull_PAC_SIGNATURE_DATA);
 224         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 225                 status = ndr_map_error2ntstatus(ndr_err);
 226                 DEBUG(0,("can't parse the SRV signature: %s\n",
 227                         nt_errstr(status)));
 228                 return status;
 229         }
 230
 231         /* Now zero the decoded structure */
 232         memset(kdc_sig_wipe->signature.data, '\0', kdc_sig_wipe->signature.length);
 233         memset(srv_sig_wipe->signature.data, '\0', srv_sig_wipe->signature.length);
 234
 235         /* and reencode, back into the same place it came from */
 236         ndr_err = ndr_push_struct_blob(kdc_sig_blob, pac_data_raw,
 237                                        kdc_sig_wipe,
 238                                        (ndr_push_flags_fn_t)ndr_push_PAC_SIGNATURE_DATA);
 239         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 240                 status = ndr_map_error2ntstatus(ndr_err);
 241                 DEBUG(0,("can't repack the KDC signature: %s\n",
 242                         nt_errstr(status)));
 243                 return status;
 244         }
 245         ndr_err = ndr_push_struct_blob(srv_sig_blob, pac_data_raw,
 246                                        srv_sig_wipe,
 247                                        (ndr_push_flags_fn_t)ndr_push_PAC_SIGNATURE_DATA);
 248         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 249                 status = ndr_map_error2ntstatus(ndr_err);
 250                 DEBUG(0,("can't repack the SRV signature: %s\n",
 251                         nt_errstr(status)));
 252                 return status;
 253         }
 254
 255         /* push out the whole structure, but now with zero'ed signatures */
 256         ndr_err = ndr_push_struct_blob(&modified_pac_blob, pac_data_raw,
 257                                        pac_data_raw,
 258                                        (ndr_push_flags_fn_t)ndr_push_PAC_DATA_RAW);
 259         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 260                 status = ndr_map_error2ntstatus(ndr_err);
 261                 DEBUG(0,("can't repack the RAW PAC: %s\n",
 262                         nt_errstr(status)));
 263                 return status;
 264         }
 265
 266         /* verify by service_key */
 267         ret = check_pac_checksum(mem_ctx,
 268                                  modified_pac_blob, srv_sig_ptr,
 269                                  context,
 270                                  service_keyblock);
 271         if (ret) {
 272                 DEBUG(1, ("PAC Decode: Failed to verify the service signature: %s\n",
 273                           smb_get_krb5_error_message(context, ret, mem_ctx)));
 274                 if (k5ret) {
 275                         *k5ret = ret;
 276                 }
 277                 return NT_STATUS_ACCESS_DENIED;
 278         }
 279
 280         if (krbtgt_keyblock) {
 281                 ret = check_pac_checksum(mem_ctx,
 282                                             srv_sig_ptr->signature, kdc_sig_ptr,
 283                                             context, krbtgt_keyblock);
 284                 if (ret) {
 285                         DEBUG(1, ("PAC Decode: Failed to verify the KDC signature: %s\n",
 286                                   smb_get_krb5_error_message(context, ret, mem_ctx)));
 287                         if (k5ret) {
 288                                 *k5ret = ret;
 289                         }
 290                         return NT_STATUS_ACCESS_DENIED;
 291                 }
 292         }
 293
 294         /* Convert to NT time, so as not to loose accuracy in comparison */
 295         unix_to_nt_time(&tgs_authtime_nttime, tgs_authtime);
 296
 297         if (tgs_authtime_nttime != logon_name->logon_time) {
 298                 DEBUG(2, ("PAC Decode: Logon time mismatch between ticket and PAC!\n"));
 299                 DEBUG(2, ("PAC Decode: PAC: %s\n", nt_time_string(mem_ctx, logon_name->logon_time)));
 300                 DEBUG(2, ("PAC Decode: Ticket: %s\n", nt_time_string(mem_ctx, tgs_authtime_nttime)));
 301                 return NT_STATUS_ACCESS_DENIED;
 302         }
 303
 304         ret = krb5_parse_name_flags(context, logon_name->account_name, KRB5_PRINCIPAL_PARSE_NO_REALM,
 305                                     &client_principal_pac);
 306         if (ret) {
 307                 DEBUG(2, ("Could not parse name from incoming PAC: [%s]: %s\n",
 308                           logon_name->account_name,
 309                           smb_get_krb5_error_message(context, ret, mem_ctx)));
 310                 if (k5ret) {
 311                         *k5ret = ret;
 312                 }
 313                 return NT_STATUS_INVALID_PARAMETER;
 314         }
 315
 316         if (!krb5_principal_compare_any_realm(context, client_principal, client_principal_pac)) {
 317                 DEBUG(2, ("Name in PAC [%s] does not match principal name in ticket\n",
 318                           logon_name->account_name));
 319                 krb5_free_principal(context, client_principal_pac);
 320                 return NT_STATUS_ACCESS_DENIED;
 321         }
 322
 323         krb5_free_principal(context, client_principal_pac);
 324
 325 #if 0
 326         if (strcasecmp(logon_info->info3.base.account_name.string,
 327                        "Administrator")== 0) {
 328                 file_save("tmp_pac_data-admin.dat",blob.data,blob.length);
 329         }
 330 #endif
 331
 332         DEBUG(3,("Found account name from PAC: %s [%s]\n",
 333                  logon_info->info3.base.account_name.string,
 334                  logon_info->info3.base.full_name.string));
 335         *pac_data_out = pac_data;
 336
 337         return NT_STATUS_OK;
 338 }
 339
 340 _PUBLIC_  NTSTATUS kerberos_pac_logon_info(TALLOC_CTX *mem_ctx,
 341                                   struct PAC_LOGON_INFO **logon_info,
 342                                   DATA_BLOB blob,
 343                                   krb5_context context,
 344                                   const krb5_keyblock *krbtgt_keyblock,
 345                                   const krb5_keyblock *service_keyblock,
 346                                   krb5_const_principal client_principal,
 347                                   time_t tgs_authtime,
 348                                   krb5_error_code *k5ret)
 349 {
 350         NTSTATUS nt_status;
 351         struct PAC_DATA *pac_data;
 352         int i;
 353         nt_status = kerberos_decode_pac(mem_ctx,
 354                                         &pac_data,
 355                                         blob,
 356                                         context,
 357                                         krbtgt_keyblock,
 358                                         service_keyblock,
 359                                         client_principal,
 360                                         tgs_authtime,
 361                                         k5ret);
 362         if (!NT_STATUS_IS_OK(nt_status)) {
 363                 return nt_status;
 364         }
 365
 366         *logon_info = NULL;
 367         for (i=0; i < pac_data->num_buffers; i++) {
 368                 if (pac_data->buffers[i].type != PAC_TYPE_LOGON_INFO) {
 369                         continue;
 370                 }
 371                 *logon_info = pac_data->buffers[i].info->logon_info.info;
 372         }
 373         if (!*logon_info) {
 374                 return NT_STATUS_INVALID_PARAMETER;
 375         }
 376         return NT_STATUS_OK;
 377 }
 378
 379 static krb5_error_code make_pac_checksum(TALLOC_CTX *mem_ctx,
 380                                          DATA_BLOB *pac_data,
 381                                          struct PAC_SIGNATURE_DATA *sig,
 382                                          krb5_context context,
 383                                          const krb5_keyblock *keyblock)
 384 {
 385         krb5_error_code ret;
 386         krb5_crypto crypto;
 387         Checksum cksum;
 388
 389
 390         ret = krb5_crypto_init(context,
 391                                keyblock,
 392                                0,
 393                                &crypto);
 394         if (ret) {
 395                 DEBUG(0,("krb5_crypto_init() failed: %s\n",
 396                           smb_get_krb5_error_message(context, ret, mem_ctx)));
 397                 return ret;
 398         }
 399         ret = krb5_create_checksum(context,
 400                                    crypto,
 401                                    KRB5_KU_OTHER_CKSUM,
 402                                    0,
 403                                    pac_data->data,
 404                                    pac_data->length,
 405                                    &cksum);
 406         if (ret) {
 407                 DEBUG(2, ("PAC Verification failed: %s\n",
 408                           smb_get_krb5_error_message(context, ret, mem_ctx)));
 409         }
 410
 411         krb5_crypto_destroy(context, crypto);
 412
 413         if (ret) {
 414                 return ret;
 415         }
 416
 417         sig->type = cksum.cksumtype;
 418         sig->signature = data_blob_talloc(mem_ctx, cksum.checksum.data, cksum.checksum.length);
 419         free_Checksum(&cksum);
 420
 421         return 0;
 422 }
 423
 424  krb5_error_code kerberos_encode_pac(TALLOC_CTX *mem_ctx,
 425                                     struct PAC_DATA *pac_data,
 426                                     krb5_context context,
 427                                     const krb5_keyblock *krbtgt_keyblock,
 428                                     const krb5_keyblock *service_keyblock,
 429                                     DATA_BLOB *pac)
 430 {
 431         NTSTATUS nt_status;
 432         krb5_error_code ret;
 433         enum ndr_err_code ndr_err;
 434         DATA_BLOB zero_blob = data_blob(NULL, 0);
 435         DATA_BLOB tmp_blob = data_blob(NULL, 0);
 436         struct PAC_SIGNATURE_DATA *kdc_checksum = NULL;
 437         struct PAC_SIGNATURE_DATA *srv_checksum = NULL;
 438         int i;
 439
 440         /* First, just get the keytypes filled in (and lengths right, eventually) */
 441         for (i=0; i < pac_data->num_buffers; i++) {
 442                 if (pac_data->buffers[i].type != PAC_TYPE_KDC_CHECKSUM) {
 443                         continue;
 444                 }
 445                 kdc_checksum = &pac_data->buffers[i].info->kdc_cksum,
 446                 ret = make_pac_checksum(mem_ctx, &zero_blob,
 447                                         kdc_checksum,
 448                                         context, krbtgt_keyblock);
 449                 if (ret) {
 450                         DEBUG(2, ("making krbtgt PAC checksum failed: %s\n",
 451                                   smb_get_krb5_error_message(context, ret, mem_ctx)));
 452                         talloc_free(pac_data);
 453                         return ret;
 454                 }
 455         }
 456
 457         for (i=0; i < pac_data->num_buffers; i++) {
 458                 if (pac_data->buffers[i].type != PAC_TYPE_SRV_CHECKSUM) {
 459                         continue;
 460                 }
 461                 srv_checksum = &pac_data->buffers[i].info->srv_cksum;
 462                 ret = make_pac_checksum(mem_ctx, &zero_blob,
 463                                         srv_checksum,
 464                                         context, service_keyblock);
 465                 if (ret) {
 466                         DEBUG(2, ("making service PAC checksum failed: %s\n",
 467                                   smb_get_krb5_error_message(context, ret, mem_ctx)));
 468                         talloc_free(pac_data);
 469                         return ret;
 470                 }
 471         }
 472
 473         if (!kdc_checksum) {
 474                 DEBUG(2, ("Invalid PAC constructed for signing, no KDC checksum present!"));
 475                 return EINVAL;
 476         }
 477         if (!srv_checksum) {
 478                 DEBUG(2, ("Invalid PAC constructed for signing, no SRV checksum present!"));
 479                 return EINVAL;
 480         }
 481
 482         /* But wipe out the actual signatures */
 483         memset(kdc_checksum->signature.data, '\0', kdc_checksum->signature.length);
 484         memset(srv_checksum->signature.data, '\0', srv_checksum->signature.length);
 485
 486         ndr_err = ndr_push_struct_blob(&tmp_blob, mem_ctx,
 487                                        pac_data,
 488                                        (ndr_push_flags_fn_t)ndr_push_PAC_DATA);
 489         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 490                 nt_status = ndr_map_error2ntstatus(ndr_err);
 491                 DEBUG(1, ("PAC (presig) push failed: %s\n", nt_errstr(nt_status)));
 492                 talloc_free(pac_data);
 493                 return EINVAL;
 494         }
 495
 496         /* Then sign the result of the previous push, where the sig was zero'ed out */
 497         ret = make_pac_checksum(mem_ctx, &tmp_blob, srv_checksum,
 498                                 context, service_keyblock);
 499
 500         /* Then sign Server checksum */
 501         ret = make_pac_checksum(mem_ctx, &srv_checksum->signature, kdc_checksum, context, krbtgt_keyblock);
 502         if (ret) {
 503                 DEBUG(2, ("making krbtgt PAC checksum failed: %s\n",
 504                           smb_get_krb5_error_message(context, ret, mem_ctx)));
 505                 talloc_free(pac_data);
 506                 return ret;
 507         }
 508
 509         /* And push it out again, this time to the world.  This relies on determanistic pointer values */
 510         ndr_err = ndr_push_struct_blob(&tmp_blob, mem_ctx,
 511                                        pac_data,
 512                                        (ndr_push_flags_fn_t)ndr_push_PAC_DATA);
 513         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 514                 nt_status = ndr_map_error2ntstatus(ndr_err);
 515                 DEBUG(1, ("PAC (final) push failed: %s\n", nt_errstr(nt_status)));
 516                 talloc_free(pac_data);
 517                 return EINVAL;
 518         }
 519
 520         *pac = tmp_blob;
 521
 522         return ret;
 523 }
 524
 525
 526  krb5_error_code kerberos_create_pac(TALLOC_CTX *mem_ctx,
 527                                      struct auth_serversupplied_info *server_info,
 528                                      krb5_context context,
 529                                      const krb5_keyblock *krbtgt_keyblock,
 530                                      const krb5_keyblock *service_keyblock,
 531                                      krb5_principal client_principal,
 532                                      time_t tgs_authtime,
 533                                      DATA_BLOB *pac)
 534 {
 535         NTSTATUS nt_status;
 536         krb5_error_code ret;
 537         struct PAC_DATA *pac_data = talloc(mem_ctx, struct PAC_DATA);
 538         struct netr_SamInfo3 *sam3;
 539         union PAC_INFO *u_LOGON_INFO;
 540         struct PAC_LOGON_INFO *LOGON_INFO;
 541         union PAC_INFO *u_LOGON_NAME;
 542         struct PAC_LOGON_NAME *LOGON_NAME;
 543         union PAC_INFO *u_KDC_CHECKSUM;
 544         union PAC_INFO *u_SRV_CHECKSUM;
 545
 546         char *name;
 547
 548         enum {
 549                 PAC_BUF_LOGON_INFO = 0,
 550                 PAC_BUF_LOGON_NAME = 1,
 551                 PAC_BUF_SRV_CHECKSUM = 2,
 552                 PAC_BUF_KDC_CHECKSUM = 3,
 553                 PAC_BUF_NUM_BUFFERS = 4
 554         };
 555
 556         if (!pac_data) {
 557                 return ENOMEM;
 558         }
 559
 560         pac_data->num_buffers = PAC_BUF_NUM_BUFFERS;
 561         pac_data->version = 0;
 562
 563         pac_data->buffers = talloc_array(pac_data,
 564                                          struct PAC_BUFFER,
 565                                          pac_data->num_buffers);
 566         if (!pac_data->buffers) {
 567                 talloc_free(pac_data);
 568                 return ENOMEM;
 569         }
 570
 571         /* LOGON_INFO */
 572         u_LOGON_INFO = talloc_zero(pac_data->buffers, union PAC_INFO);
 573         if (!u_LOGON_INFO) {
 574                 talloc_free(pac_data);
 575                 return ENOMEM;
 576         }
 577         pac_data->buffers[PAC_BUF_LOGON_INFO].type = PAC_TYPE_LOGON_INFO;
 578         pac_data->buffers[PAC_BUF_LOGON_INFO].info = u_LOGON_INFO;
 579
 580         /* LOGON_NAME */
 581         u_LOGON_NAME = talloc_zero(pac_data->buffers, union PAC_INFO);
 582         if (!u_LOGON_NAME) {
 583                 talloc_free(pac_data);
 584                 return ENOMEM;
 585         }
 586         pac_data->buffers[PAC_BUF_LOGON_NAME].type = PAC_TYPE_LOGON_NAME;
 587         pac_data->buffers[PAC_BUF_LOGON_NAME].info = u_LOGON_NAME;
 588         LOGON_NAME = &u_LOGON_NAME->logon_name;
 589
 590         /* SRV_CHECKSUM */
 591         u_SRV_CHECKSUM = talloc_zero(pac_data->buffers, union PAC_INFO);
 592         if (!u_SRV_CHECKSUM) {
 593                 talloc_free(pac_data);
 594                 return ENOMEM;
 595         }
 596         pac_data->buffers[PAC_BUF_SRV_CHECKSUM].type = PAC_TYPE_SRV_CHECKSUM;
 597         pac_data->buffers[PAC_BUF_SRV_CHECKSUM].info = u_SRV_CHECKSUM;
 598
 599         /* KDC_CHECKSUM */
 600         u_KDC_CHECKSUM = talloc_zero(pac_data->buffers, union PAC_INFO);
 601         if (!u_KDC_CHECKSUM) {
 602                 talloc_free(pac_data);
 603                 return ENOMEM;
 604         }
 605         pac_data->buffers[PAC_BUF_KDC_CHECKSUM].type = PAC_TYPE_KDC_CHECKSUM;
 606         pac_data->buffers[PAC_BUF_KDC_CHECKSUM].info = u_KDC_CHECKSUM;
 607
 608         /* now the real work begins... */
 609
 610         LOGON_INFO = talloc_zero(u_LOGON_INFO, struct PAC_LOGON_INFO);
 611         if (!LOGON_INFO) {
 612                 talloc_free(pac_data);
 613                 return ENOMEM;
 614         }
 615         nt_status = auth_convert_server_info_saminfo3(LOGON_INFO, server_info, &sam3);
 616         if (!NT_STATUS_IS_OK(nt_status)) {
 617                 DEBUG(1, ("Getting Samba info failed: %s\n", nt_errstr(nt_status)));
 618                 talloc_free(pac_data);
 619                 return EINVAL;
 620         }
 621
 622         u_LOGON_INFO->logon_info.info           = LOGON_INFO;
 623         LOGON_INFO->info3 = *sam3;
 624
 625         ret = krb5_unparse_name_flags(context, client_principal,
 626                                       KRB5_PRINCIPAL_UNPARSE_NO_REALM, &name);
 627         if (ret) {
 628                 return ret;
 629         }
 630         LOGON_NAME->account_name        = talloc_strdup(LOGON_NAME, name);
 631         free(name);
 632         /*
 633           this logon_time field is absolutely critical. This is what
 634           caused all our PAC troubles :-)
 635         */
 636         unix_to_nt_time(&LOGON_NAME->logon_time, tgs_authtime);
 637
 638         ret = kerberos_encode_pac(mem_ctx,
 639                                   pac_data,
 640                                   context,
 641                                   krbtgt_keyblock,
 642                                   service_keyblock,
 643                                   pac);
 644         talloc_free(pac_data);
 645         return ret;
 646 }
 647
 648 krb5_error_code kerberos_pac_to_server_info(TALLOC_CTX *mem_ctx,
 649                                                 krb5_pac pac,
 650                                                 krb5_context context,
 651                                                 struct auth_serversupplied_info **server_info)
 652 {
 653         NTSTATUS nt_status;
 654         enum ndr_err_code ndr_err;
 655         krb5_error_code ret;
 656
 657         DATA_BLOB pac_logon_info_in, pac_srv_checksum_in, pac_kdc_checksum_in;
 658         krb5_data k5pac_logon_info_in, k5pac_srv_checksum_in, k5pac_kdc_checksum_in;
 659
 660         union PAC_INFO info;
 661         struct auth_serversupplied_info *server_info_out;
 662
 663         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 664
 665         if (!tmp_ctx) {
 666                 return ENOMEM;
 667         }
 668
 669         ret = krb5_pac_get_buffer(context, pac, PAC_TYPE_LOGON_INFO, &k5pac_logon_info_in);
 670         if (ret != 0) {
 671                 talloc_free(tmp_ctx);
 672                 return EINVAL;
 673         }
 674
 675         pac_logon_info_in = data_blob_const(k5pac_logon_info_in.data, k5pac_logon_info_in.length);
 676
 677         ndr_err = ndr_pull_union_blob(&pac_logon_info_in, tmp_ctx, &info,
 678                                       PAC_TYPE_LOGON_INFO,
 679                                       (ndr_pull_flags_fn_t)ndr_pull_PAC_INFO);
 680         krb5_data_free(&k5pac_logon_info_in);
 681         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err) || !info.logon_info.info) {
 682                 nt_status = ndr_map_error2ntstatus(ndr_err);
 683                 DEBUG(0,("can't parse the PAC LOGON_INFO: %s\n", nt_errstr(nt_status)));
 684                 talloc_free(tmp_ctx);
 685                 return EINVAL;
 686         }
 687
 688         /* Pull this right into the normal auth sysstem structures */
 689         nt_status = make_server_info_pac(mem_ctx,
 690                                          info.logon_info.info,
 691                                          &server_info_out);
 692         if (!NT_STATUS_IS_OK(nt_status)) {
 693                 talloc_free(tmp_ctx);
 694                 return EINVAL;
 695         }
 696
 697         ret = krb5_pac_get_buffer(context, pac, PAC_TYPE_SRV_CHECKSUM, &k5pac_srv_checksum_in);
 698         if (ret != 0) {
 699                 talloc_free(tmp_ctx);
 700                 return ret;
 701         }
 702
 703         pac_srv_checksum_in = data_blob_const(k5pac_srv_checksum_in.data, k5pac_srv_checksum_in.length);
 704
 705         ndr_err = ndr_pull_struct_blob(&pac_srv_checksum_in, server_info_out,
 706                                        &server_info_out->pac_srv_sig,
 707                                        (ndr_pull_flags_fn_t)ndr_pull_PAC_SIGNATURE_DATA);
 708         krb5_data_free(&k5pac_srv_checksum_in);
 709         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 710                 nt_status = ndr_map_error2ntstatus(ndr_err);
 711                 DEBUG(0,("can't parse the KDC signature: %s\n",
 712                         nt_errstr(nt_status)));
 713                 return EINVAL;
 714         }
 715
 716         ret = krb5_pac_get_buffer(context, pac, PAC_TYPE_KDC_CHECKSUM, &k5pac_kdc_checksum_in);
 717         if (ret != 0) {
 718                 talloc_free(tmp_ctx);
 719                 return ret;
 720         }
 721
 722         pac_kdc_checksum_in = data_blob_const(k5pac_kdc_checksum_in.data, k5pac_kdc_checksum_in.length);
 723
 724         ndr_err = ndr_pull_struct_blob(&pac_kdc_checksum_in, server_info_out,
 725                                        &server_info_out->pac_kdc_sig,
 726                                        (ndr_pull_flags_fn_t)ndr_pull_PAC_SIGNATURE_DATA);
 727         krb5_data_free(&k5pac_kdc_checksum_in);
 728         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 729                 nt_status = ndr_map_error2ntstatus(ndr_err);
 730                 DEBUG(0,("can't parse the KDC signature: %s\n",
 731                         nt_errstr(nt_status)));
 732                 return EINVAL;
 733         }
 734
 735         *server_info = server_info_out;
 736
 737         return 0;
 738 }
 739
 740
 741 NTSTATUS kerberos_pac_blob_to_server_info(TALLOC_CTX *mem_ctx,
 742                                                      DATA_BLOB pac_blob,
 743                                                      krb5_context context,
 744                                                      struct auth_serversupplied_info **server_info)
 745 {
 746         krb5_error_code ret;
 747         krb5_pac pac;
 748         ret = krb5_pac_parse(context,
 749                              pac_blob.data, pac_blob.length,
 750                              &pac);
 751         if (ret) {
 752                 return map_nt_error_from_unix(ret);
 753         }
 754
 755
 756         ret = kerberos_pac_to_server_info(mem_ctx, pac, context, server_info);
 757         krb5_pac_free(context, pac);
 758         if (ret) {
 759                 return map_nt_error_from_unix(ret);
 760         }
 761         return NT_STATUS_OK;
 762 }