src/libimcv/plugins/imv_attestation/imv_attestation_process.c

   1 /*
   2  * Copyright (C) 2011 Sansar Choinyambuu
   3  * HSR Hochschule fuer Technik Rapperswil
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2 of the License, or (at your
   8  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * for more details.
  14  */
  15
  16 #include "imv_attestation_process.h"
  17
  18 #include <ietf/ietf_attr_pa_tnc_error.h>
  19
  20 #include <pts/pts.h>
  21
  22 #include <tcg/tcg_pts_attr_aik.h>
  23 #include <tcg/tcg_pts_attr_dh_nonce_params_resp.h>
  24 #include <tcg/tcg_pts_attr_file_meas.h>
  25 #include <tcg/tcg_pts_attr_meas_algo.h>
  26 #include <tcg/tcg_pts_attr_proto_caps.h>
  27 #include <tcg/tcg_pts_attr_simple_comp_evid.h>
  28 #include <tcg/tcg_pts_attr_simple_evid_final.h>
  29 #include <tcg/tcg_pts_attr_tpm_version_info.h>
  30 #include <tcg/tcg_pts_attr_unix_file_meta.h>
  31
  32 #include <debug.h>
  33 #include <crypto/hashers/hasher.h>
  34
  35 #include <inttypes.h>
  36
  37 bool imv_attestation_process(pa_tnc_attr_t *attr, linked_list_t *attr_list,
  38                                                          imv_attestation_state_t *attestation_state,
  39                                                          pts_meas_algorithms_t supported_algorithms,
  40                                                          pts_dh_group_t supported_dh_groups,
  41                                                          pts_database_t *pts_db,
  42                                                          credential_manager_t *pts_credmgr)
  43 {
  44         chunk_t attr_info;
  45         pts_t *pts;
  46
  47         pts = attestation_state->get_pts(attestation_state);
  48
  49         switch (attr->get_type(attr))
  50         {
  51                 case TCG_PTS_PROTO_CAPS:
  52                 {
  53                         tcg_pts_attr_proto_caps_t *attr_cast;
  54                         pts_proto_caps_flag_t flags;
  55
  56                         attr_cast = (tcg_pts_attr_proto_caps_t*)attr;
  57                         flags = attr_cast->get_flags(attr_cast);
  58                         pts->set_proto_caps(pts, flags);
  59                         break;
  60                 }
  61                 case TCG_PTS_MEAS_ALGO_SELECTION:
  62                 {
  63                         tcg_pts_attr_meas_algo_t *attr_cast;
  64                         pts_meas_algorithms_t selected_algorithm;
  65
  66                         attr_cast = (tcg_pts_attr_meas_algo_t*)attr;
  67                         selected_algorithm = attr_cast->get_algorithms(attr_cast);
  68                         if (!(selected_algorithm & supported_algorithms))
  69                         {
  70                                 DBG1(DBG_IMV, "PTS-IMC selected unsupported"
  71                                                           " measurement algorithm");
  72                                 return FALSE;
  73                         }
  74                         pts->set_meas_algorithm(pts, selected_algorithm);
  75                         break;
  76                 }
  77                 case TCG_PTS_DH_NONCE_PARAMS_RESP:
  78                 {
  79                         tcg_pts_attr_dh_nonce_params_resp_t *attr_cast;
  80                         int nonce_len, min_nonce_len;
  81                         pts_dh_group_t dh_group;
  82                         pts_meas_algorithms_t offered_algorithms, selected_algorithm;
  83                         chunk_t responder_value, responder_nonce;
  84
  85                         attr_cast = (tcg_pts_attr_dh_nonce_params_resp_t*)attr;
  86                         responder_nonce = attr_cast->get_responder_nonce(attr_cast);
  87
  88                         /* check compliance of responder nonce length */
  89                         min_nonce_len = lib->settings->get_int(lib->settings,
  90                                                 "libimcv.plugins.imv-attestation.min_nonce_len", 0);
  91                         nonce_len = responder_nonce.len;
  92                         if (nonce_len < PTS_MIN_NONCE_LEN ||
  93                            (min_nonce_len > 0 && nonce_len < min_nonce_len))
  94                         {
  95                                 attr = pts_dh_nonce_error_create(
  96                                                                         max(PTS_MIN_NONCE_LEN, min_nonce_len),
  97                                                                                 PTS_MAX_NONCE_LEN);
  98                                 attr_list->insert_last(attr_list, attr);
  99                                 break;
 100                         }
 101
 102                         dh_group = attr_cast->get_dh_group(attr_cast);
 103                         if (!(dh_group & supported_dh_groups))
 104                         {
 105                                 DBG1(DBG_IMV, "PTS-IMC selected unsupported DH group");
 106                                 return FALSE;
 107                         }
 108
 109                         offered_algorithms = attr_cast->get_hash_algo_set(attr_cast);
 110                         selected_algorithm = pts_meas_algo_select(supported_algorithms,
 111                                                                                                           offered_algorithms);
 112                         if (selected_algorithm == PTS_MEAS_ALGO_NONE)
 113                         {
 114                                 attr = pts_hash_alg_error_create(supported_algorithms);
 115                                 attr_list->insert_last(attr_list, attr);
 116                                 break;
 117                         }
 118                         pts->set_dh_hash_algorithm(pts, selected_algorithm);
 119
 120                         if (!pts->create_dh_nonce(pts, dh_group, nonce_len))
 121                         {
 122                                 return FALSE;
 123                         }
 124
 125                         responder_value = attr_cast->get_responder_value(attr_cast);
 126                         pts->set_peer_public_value(pts, responder_value,
 127                                                                                         responder_nonce);
 128
 129                         /* Calculate secret assessment value */
 130                         if (!pts->calculate_secret(pts))
 131                         {
 132                                 return FALSE;
 133                         }
 134                         break;
 135                 }
 136                 case TCG_PTS_TPM_VERSION_INFO:
 137                 {
 138                         tcg_pts_attr_tpm_version_info_t *attr_cast;
 139                         chunk_t tpm_version_info;
 140
 141                         attr_cast = (tcg_pts_attr_tpm_version_info_t*)attr;
 142                         tpm_version_info = attr_cast->get_tpm_version_info(attr_cast);
 143                         pts->set_tpm_version_info(pts, tpm_version_info);
 144                         break;
 145                 }
 146                 case TCG_PTS_AIK:
 147                 {
 148                         tcg_pts_attr_aik_t *attr_cast;
 149                         certificate_t *aik, *issuer;
 150                         enumerator_t *e;
 151                         bool trusted = FALSE;
 152
 153                         attr_cast = (tcg_pts_attr_aik_t*)attr;
 154                         aik = attr_cast->get_aik(attr_cast);
 155                         if (!aik)
 156                         {
 157                                 DBG1(DBG_IMV, "AIK unavailable");
 158                                 return FALSE;
 159                         }
 160                         if (aik->get_type(aik) == CERT_X509)
 161                         {
 162                                 DBG1(DBG_IMV, "verifying AIK certificate");
 163                                 e = pts_credmgr->create_trusted_enumerator(pts_credmgr,
 164                                                         KEY_ANY, aik->get_issuer(aik), FALSE);
 165                                 while (e->enumerate(e, &issuer))
 166                                 {
 167                                         if (aik->issued_by(aik, issuer))
 168                                         {
 169                                                 trusted = TRUE;
 170                                                 break;
 171                                         }
 172                                 }
 173                                 e->destroy(e);
 174                                 DBG1(DBG_IMV, "AIK certificate is %strusted",
 175                                                            trusted ? "" : "not ");
 176                         }
 177                         pts->set_aik(pts, aik);
 178                         break;
 179                 }
 180                 case TCG_PTS_SIMPLE_COMP_EVID:
 181                 {
 182                         tcg_pts_attr_simple_comp_evid_t *attr_cast;
 183                         bool pcr_info_inclided;
 184                         pts_attr_simple_comp_evid_flag_t flags;
 185                         u_int32_t depth, comp_vendor_id, extended_pcr;
 186                         u_int8_t family, measurement_type;
 187                         pts_qualifier_t qualifier;
 188                         pts_funct_comp_name_t name;
 189                         pts_meas_algorithms_t hash_algorithm;
 190                         pts_pcr_transform_t transformation;
 191                         chunk_t measurement_time, policy_uri;
 192                         chunk_t pcr_before, pcr_after, measurement;
 193
 194                         attr_cast = (tcg_pts_attr_simple_comp_evid_t*)attr;
 195                         attr_info = attr->get_value(attr);
 196
 197                         pcr_info_inclided = attr_cast->is_pcr_info_included(attr_cast);
 198                         flags = attr_cast->get_flags(attr_cast);
 199                         depth = attr_cast->get_sub_component_depth(attr_cast);
 200                         /* TODO: Implement check of components with its sub-components */
 201                         if (depth != 0)
 202                         {
 203                                 DBG1(DBG_IMV, "Current version of Attestation IMV does not"
 204                                                 " support sub component measurement deeper than zero");
 205                         }
 206                         comp_vendor_id = attr_cast->get_spec_comp_funct_name_vendor_id(
 207                                                                                                                 attr_cast);
 208                         if (comp_vendor_id != PEN_TCG)
 209                         {
 210                                 DBG1(DBG_IMV, "Current version of Attestation IMV supports"
 211                                                           "only functional component namings by TCG ");
 212                                 break;
 213                         }
 214                         family = attr_cast->get_family(attr_cast);
 215                         if (family)
 216                         {
 217                                 attr = ietf_attr_pa_tnc_error_create(PEN_TCG,
 218                                                                 TCG_PTS_INVALID_NAME_FAM, attr_info);
 219                                 attr_list->insert_last(attr_list, attr);
 220                                 break;
 221                         }
 222                         qualifier = attr_cast->get_qualifier(attr_cast);
 223
 224                         /* Check if Unknown or Wildcard was set for qualifier */
 225                         if (qualifier.kernel && qualifier.sub_component &&
 226                            (qualifier.type & PTS_FUNC_COMP_TYPE_ALL))
 227                         {
 228                                 DBG1(DBG_IMV, "Wildcard was set for the qualifier "
 229                                                           "of functional component");
 230                                 return FALSE;
 231                         }
 232                         else if (!qualifier.kernel && !qualifier.sub_component &&
 233                                         (qualifier.type & PTS_FUNC_COMP_TYPE_UNKNOWN))
 234                         {
 235                                 DBG1(DBG_IMV, "Unknown feature was set for the qualifier "
 236                                                           "of functional component");
 237                                 return FALSE;
 238                         }
 239                         else
 240                         {
 241                                 /* TODO: Implement what todo with received qualifier */
 242                         }
 243
 244                         name = attr_cast->get_comp_funct_name(attr_cast);
 245                         measurement_type = attr_cast->get_measurement_type(attr_cast);
 246                         hash_algorithm = attr_cast->get_hash_algorithm(attr_cast);
 247                         transformation = attr_cast->get_pcr_trans(attr_cast);
 248                         measurement_time = attr_cast->get_measurement_time(attr_cast);
 249
 250                         /* Call getters of optional fields when corresponding flag is set */
 251                         if (pcr_info_inclided)
 252                         {
 253                                 pcr_entry_t *entry;
 254
 255                                 extended_pcr = attr_cast->get_extended_pcr(attr_cast);
 256                                 pcr_before = attr_cast->get_pcr_before_value(attr_cast);
 257                                 pcr_after = attr_cast->get_pcr_after_value(attr_cast);
 258                                 measurement = attr_cast->get_comp_measurement(attr_cast);
 259
 260                                 DBG4(DBG_IMV,"PCR: %d was extended with %B",
 261                                          extended_pcr, &measurement);
 262                                 DBG4(DBG_IMV,"PCR: %d before value: %B",
 263                                          extended_pcr, &pcr_before);
 264                                 DBG4(DBG_IMV,"PCR: %d after value: %B",
 265                                          extended_pcr, &pcr_after);
 266
 267                                 entry = malloc_thing(pcr_entry_t);
 268                                 entry->pcr_number = extended_pcr;
 269                                 strncpy(entry->pcr_value, pcr_after.ptr, PCR_LEN);
 270                                 pts->add_pcr_entry(pts, entry);
 271
 272                         }
 273                         if (flags != PTS_SIMPLE_COMP_EVID_FLAG_NO_VALID)
 274                         {
 275                                 policy_uri = attr_cast->get_policy_uri(attr_cast);
 276                                 DBG1(DBG_IMV, "This version of Attestation IMV can not handle"
 277                                          " Verification Policies");
 278                         }
 279
 280                         break;
 281                 }
 282                 case TCG_PTS_SIMPLE_EVID_FINAL:
 283                 {
 284                         tcg_pts_attr_simple_evid_final_t *attr_cast;
 285                         pts_simple_evid_final_flag_t flags;
 286                         chunk_t pcr_comp;
 287                         chunk_t tpm_quote_sign;
 288                         chunk_t evid_sign;
 289                         bool evid_signature_included;
 290
 291                         /** TODO: Ignoring Composite Hash Algorithm field
 292                          * No flag defined which indicates the precense of it
 293                          */
 294                         attr_cast = (tcg_pts_attr_simple_evid_final_t*)attr;
 295                         evid_signature_included = attr_cast->is_evid_sign_included(attr_cast);
 296                         flags = attr_cast->get_flags(attr_cast);
 297
 298                         if ((flags == PTS_SIMPLE_EVID_FINAL_FLAG_TPM_QUOTE_INFO2) ||
 299                                 (flags == PTS_SIMPLE_EVID_FINAL_FLAG_TPM_QUOTE_INFO2_CAP_VER))
 300                         {
 301                                 DBG1(DBG_IMV, "This version of Attestation IMV can not handle"
 302                                          " TPM Quote Info2 structure");
 303                                 break;
 304                         }
 305                         if (flags == PTS_SIMPLE_EVID_FINAL_FLAG_TPM_QUOTE_INFO)
 306                         {
 307                                 chunk_t pcr_composite, quote_info, quote_digest;
 308                                 hasher_t *hasher;
 309                                 pcr_comp = attr_cast->get_pcr_comp(attr_cast);
 310                                 tpm_quote_sign = attr_cast->get_tpm_quote_sign(attr_cast);
 311
 312                                 /* Construct PCR Composite and TPM Quote Info structures*/
 313                                 if (!pts->get_quote_info(pts, &pcr_composite, &quote_info))
 314                                 {
 315                                         DBG1(DBG_IMV, "unable to contruct TPM Quote Info");
 316                                         return FALSE;
 317                                 }
 318
 319                                 /* Check calculated PCR composite structure matches with received */
 320                                 if (pcr_comp.ptr && !chunk_equals(pcr_comp, pcr_composite))
 321                                 {
 322                                         DBG1(DBG_IMV, "received PCR Compsosite didn't match"
 323                                                                   " with constructed");
 324                                         chunk_clear(&pcr_composite);
 325                                         chunk_clear(&quote_info);
 326                                         return FALSE;
 327                                 }
 328                                 DBG2(DBG_IMV, "received PCR Composite matches with constructed");
 329                                 chunk_clear(&pcr_composite);
 330
 331                                 /* SHA1(TPM Quote Info) expected from IMC */
 332                                 hasher = lib->crypto->create_hasher(lib->crypto, HASH_SHA1);
 333                                 hasher->allocate_hash(hasher, quote_info, &quote_digest);
 334                                 hasher->destroy(hasher);
 335                                 chunk_clear(&quote_info);
 336
 337                                 if (tpm_quote_sign.ptr &&
 338                                         !pts->verify_quote_signature(pts, quote_digest,
 339                                                                                                  tpm_quote_sign))
 340                                 {
 341                                         chunk_clear(&quote_digest);
 342                                         return FALSE;
 343                                 }
 344
 345                                 DBG2(DBG_IMV, "signature verification succeeded for "
 346                                                           "TPM Quote Info");
 347                                 chunk_clear(&quote_digest);
 348                         }
 349
 350                         if (evid_signature_included)
 351                         {
 352                                 /** TODO: What to do with Evidence Signature */
 353                                 evid_sign = attr_cast->get_evid_sign(attr_cast);
 354                                 DBG1(DBG_IMV, "This version of Attestation IMV can not handle"
 355                                          " Optional Evidence Signature field");
 356                         }
 357
 358                         break;
 359                 }
 360                 case TCG_PTS_FILE_MEAS:
 361                 {
 362                         tcg_pts_attr_file_meas_t *attr_cast;
 363                         u_int16_t request_id;
 364                         int file_count, file_id;
 365                         pts_meas_algorithms_t algo;
 366                         pts_file_meas_t *measurements;
 367                         char *platform_info;
 368                         enumerator_t *e_hash;
 369                         bool is_dir;
 370
 371                         platform_info = pts->get_platform_info(pts);
 372                         if (!pts_db || !platform_info)
 373                         {
 374                                 break;
 375                         }
 376
 377                         attr_cast = (tcg_pts_attr_file_meas_t*)attr;
 378                         measurements = attr_cast->get_measurements(attr_cast);
 379                         algo = pts->get_meas_algorithm(pts);
 380                         request_id = measurements->get_request_id(measurements);
 381                         file_count = measurements->get_file_count(measurements);
 382
 383                         DBG1(DBG_IMV, "measurement request %d returned %d file%s:",
 384                                  request_id, file_count, (file_count == 1) ? "":"s");
 385
 386                         if (!attestation_state->check_off_request(attestation_state,
 387                                 request_id, &file_id, &is_dir))
 388                         {
 389                                 DBG1(DBG_IMV, "  no entry found for this request");
 390                                 break;
 391                         }
 392
 393                         /* check hashes from database against measurements */
 394                         e_hash = pts_db->create_hash_enumerator(pts_db,
 395                                                         platform_info, algo, file_id, is_dir);
 396                         if (!measurements->verify(measurements, e_hash, is_dir))
 397                         {
 398                                 attestation_state->set_measurement_error(attestation_state);
 399                         }
 400                         e_hash->destroy(e_hash);
 401                         break;
 402                 }
 403                 case TCG_PTS_UNIX_FILE_META:
 404                 {
 405                         tcg_pts_attr_file_meta_t *attr_cast;
 406                         int file_count;
 407                         pts_file_meta_t *metadata;
 408                         pts_file_metadata_t *entry;
 409                         time_t created, modified, accessed;
 410                         bool utc = FALSE;
 411                         enumerator_t *e;
 412
 413                         attr_cast = (tcg_pts_attr_file_meta_t*)attr;
 414                         metadata = attr_cast->get_metadata(attr_cast);
 415                         file_count = metadata->get_file_count(metadata);
 416
 417                         DBG1(DBG_IMV, "metadata request returned %d file%s:",
 418                                  file_count, (file_count == 1) ? "":"s");
 419
 420                         e = metadata->create_enumerator(metadata);
 421                         while (e->enumerate(e, &entry))
 422                         {
 423                                 DBG1(DBG_IMV, " '%s' (%"PRIu64" bytes)"
 424                                                           " owner %"PRIu64", group %"PRIu64", type %d",
 425                                          entry->filename, entry->filesize, entry->owner,
 426                                          entry->group, entry->type);
 427
 428                                 created = entry->created;
 429                                 modified = entry->modified;
 430                                 accessed = entry->accessed;
 431
 432                                 DBG1(DBG_IMV, "    created %T, modified %T, accessed %T",
 433                                          &created, utc, &modified, utc, &accessed, utc);
 434                         }
 435                         e->destroy(e);
 436                         break;
 437                 }
 438
 439                 /* TODO: Not implemented yet */
 440                 case TCG_PTS_INTEG_MEAS_LOG:
 441                 /* Attributes using XML */
 442                 case TCG_PTS_TEMPL_REF_MANI_SET_META:
 443                 case TCG_PTS_VERIFICATION_RESULT:
 444                 case TCG_PTS_INTEG_REPORT:
 445                 /* On Windows only*/
 446                 case TCG_PTS_WIN_FILE_META:
 447                 case TCG_PTS_REGISTRY_VALUE:
 448                 /* Received on IMC side only*/
 449                 case TCG_PTS_REQ_PROTO_CAPS:
 450                 case TCG_PTS_DH_NONCE_PARAMS_REQ:
 451                 case TCG_PTS_DH_NONCE_FINISH:
 452                 case TCG_PTS_MEAS_ALGO:
 453                 case TCG_PTS_GET_TPM_VERSION_INFO:
 454                 case TCG_PTS_REQ_TEMPL_REF_MANI_SET_META:
 455                 case TCG_PTS_UPDATE_TEMPL_REF_MANI:
 456                 case TCG_PTS_GET_AIK:
 457                 case TCG_PTS_REQ_FUNCT_COMP_EVID:
 458                 case TCG_PTS_GEN_ATTEST_EVID:
 459                 case TCG_PTS_REQ_FILE_META:
 460                 case TCG_PTS_REQ_FILE_MEAS:
 461                 case TCG_PTS_REQ_INTEG_MEAS_LOG:
 462                 default:
 463                         DBG1(DBG_IMV, "received unsupported attribute '%N'",
 464                                  tcg_attr_names, attr->get_type(attr));
 465                         break;
 466         }
 467         return TRUE;
 468 }
 469