refactored simple component evidence
[strongswan.git] / 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_FILE_MEAS:
181 {
182 tcg_pts_attr_file_meas_t *attr_cast;
183 u_int16_t request_id;
184 int file_count, file_id;
185 pts_meas_algorithms_t algo;
186 pts_file_meas_t *measurements;
187 char *platform_info;
188 enumerator_t *e_hash;
189 bool is_dir;
190
191 platform_info = pts->get_platform_info(pts);
192 if (!pts_db || !platform_info)
193 {
194 DBG1(DBG_IMV, "%s%s%s not available",
195 (pts_db) ? "" : "pts database",
196 (!pts_db && !platform_info) ? "and" : "",
197 (platform_info) ? "" : "platform info");
198 break;
199 }
200
201 attr_cast = (tcg_pts_attr_file_meas_t*)attr;
202 measurements = attr_cast->get_measurements(attr_cast);
203 algo = pts->get_meas_algorithm(pts);
204 request_id = measurements->get_request_id(measurements);
205 file_count = measurements->get_file_count(measurements);
206
207 DBG1(DBG_IMV, "measurement request %d returned %d file%s:",
208 request_id, file_count, (file_count == 1) ? "":"s");
209
210 if (!attestation_state->check_off_file_meas_request(attestation_state,
211 request_id, &file_id, &is_dir))
212 {
213 DBG1(DBG_IMV, " no entry found for file measurement request %d",
214 request_id);
215 break;
216 }
217
218 /* check hashes from database against measurements */
219 e_hash = pts_db->create_file_hash_enumerator(pts_db,
220 platform_info, algo, file_id, is_dir);
221 if (!measurements->verify(measurements, e_hash, is_dir))
222 {
223 attestation_state->set_measurement_error(attestation_state);
224 }
225 e_hash->destroy(e_hash);
226 break;
227 }
228 case TCG_PTS_UNIX_FILE_META:
229 {
230 tcg_pts_attr_file_meta_t *attr_cast;
231 int file_count;
232 pts_file_meta_t *metadata;
233 pts_file_metadata_t *entry;
234 time_t created, modified, accessed;
235 bool utc = FALSE;
236 enumerator_t *e;
237
238 attr_cast = (tcg_pts_attr_file_meta_t*)attr;
239 metadata = attr_cast->get_metadata(attr_cast);
240 file_count = metadata->get_file_count(metadata);
241
242 DBG1(DBG_IMV, "metadata request returned %d file%s:",
243 file_count, (file_count == 1) ? "":"s");
244
245 e = metadata->create_enumerator(metadata);
246 while (e->enumerate(e, &entry))
247 {
248 DBG1(DBG_IMV, " '%s' (%"PRIu64" bytes)"
249 " owner %"PRIu64", group %"PRIu64", type %N",
250 entry->filename, entry->filesize, entry->owner,
251 entry->group, pts_file_type_names, entry->type);
252
253 created = entry->created;
254 modified = entry->modified;
255 accessed = entry->accessed;
256
257 DBG1(DBG_IMV, " created %T, modified %T, accessed %T",
258 &created, utc, &modified, utc, &accessed, utc);
259 }
260 e->destroy(e);
261 break;
262 }
263 case TCG_PTS_SIMPLE_COMP_EVID:
264 {
265 tcg_pts_attr_simple_comp_evid_t *attr_cast;
266 pts_comp_func_name_t *name;
267 pts_comp_evidence_t *evidence;
268 pts_component_t *comp;
269 u_int32_t depth;
270 status_t status;
271
272 attr_cast = (tcg_pts_attr_simple_comp_evid_t*)attr;
273 evidence = attr_cast->get_comp_evidence(attr_cast);
274 name = evidence->get_comp_func_name(evidence, &depth);
275
276 comp = attestation_state->check_off_component(attestation_state, name);
277 if (!comp)
278 {
279 DBG1(DBG_IMV, " no entry found for component evidence request");
280 evidence->destroy(evidence);
281 break;
282 }
283 status = comp->verify(comp, pts, pts_db, evidence);
284
285 switch (status)
286 {
287 default:
288 case FAILED:
289 attestation_state->set_measurement_error(attestation_state);
290 /* fall through to next case */
291 case SUCCESS:
292 comp->destroy(comp);
293 break;
294 case NEED_MORE:
295 /* re-enter component into list */
296 attestation_state->add_component(attestation_state, comp);
297 }
298 evidence->destroy(evidence);
299 break;
300 }
301 case TCG_PTS_SIMPLE_EVID_FINAL:
302 {
303 tcg_pts_attr_simple_evid_final_t *attr_cast;
304 pts_simple_evid_final_flag_t flags;
305 pts_meas_algorithms_t composite_algorithm;
306 chunk_t pcr_comp;
307 chunk_t tpm_quote_sign;
308 chunk_t evid_sign;
309 bool evid_signature_included = FALSE, use_quote2 = FALSE,
310 ver_info_included = FALSE;
311 chunk_t pcr_composite, quote_info;
312
313 attr_cast = (tcg_pts_attr_simple_evid_final_t*)attr;
314 evid_signature_included = attr_cast->is_evid_sign_included(attr_cast);
315 flags = attr_cast->get_flags(attr_cast);
316
317 /** Optional Composite Hash Algorithm field is always present
318 * Field has value of all zeroes if not used.
319 * Implemented adhering the suggestion of Paul Sangster 28.Oct.2011
320 */
321 composite_algorithm = attr_cast->get_comp_hash_algorithm(attr_cast);
322
323 if (flags != PTS_SIMPLE_EVID_FINAL_FLAG_NO)
324 {
325 if ((flags == PTS_SIMPLE_EVID_FINAL_FLAG_TPM_QUOTE_INFO2) ||
326 (flags == PTS_SIMPLE_EVID_FINAL_FLAG_TPM_QUOTE_INFO2_CAP_VER))
327 {
328 use_quote2 = TRUE;
329 }
330 if (flags == PTS_SIMPLE_EVID_FINAL_FLAG_TPM_QUOTE_INFO2_CAP_VER)
331 {
332 ver_info_included = TRUE;
333 }
334
335 pcr_comp = attr_cast->get_pcr_comp(attr_cast);
336 tpm_quote_sign = attr_cast->get_tpm_quote_sign(attr_cast);
337
338 if (!pcr_comp.ptr || !tpm_quote_sign.ptr)
339 {
340 DBG1(DBG_IMV, "PCR composite: %B", &pcr_comp);
341 DBG1(DBG_IMV, "TPM Quote Signature: %B", &tpm_quote_sign);
342 DBG1(DBG_IMV, "Either PCR Composite or Quote Signature missing");
343 return FALSE;
344 }
345
346 /* Construct PCR Composite and TPM Quote Info structures */
347 if (!pts->get_quote_info(pts, use_quote2, ver_info_included,
348 composite_algorithm, &pcr_composite, &quote_info))
349 {
350 DBG1(DBG_IMV, "unable to contruct TPM Quote Info");
351 return FALSE;
352 }
353
354 /* Check calculated PCR composite matches with received */
355 if (!chunk_equals(pcr_comp, pcr_composite))
356 {
357 DBG1(DBG_IMV, "received PCR Compsosite didn't match"
358 " with constructed");
359 chunk_clear(&pcr_composite);
360 chunk_clear(&quote_info);
361 return FALSE;
362 }
363 DBG2(DBG_IMV, "received PCR Composite matches with constructed");
364 chunk_clear(&pcr_composite);
365
366 if (!pts->verify_quote_signature(pts, quote_info, tpm_quote_sign))
367 {
368 chunk_clear(&quote_info);
369 return FALSE;
370 }
371
372 DBG2(DBG_IMV, "signature verification succeeded for "
373 "TPM Quote Info");
374 chunk_clear(&quote_info);
375 }
376
377 if (evid_signature_included)
378 {
379 /** TODO: What to do with Evidence Signature */
380 evid_sign = attr_cast->get_evid_sign(attr_cast);
381 DBG1(DBG_IMV, "This version of Attestation IMV can not handle"
382 " Optional Evidence Signature field");
383 }
384
385 break;
386 }
387
388 /* TODO: Not implemented yet */
389 case TCG_PTS_INTEG_MEAS_LOG:
390 /* Attributes using XML */
391 case TCG_PTS_TEMPL_REF_MANI_SET_META:
392 case TCG_PTS_VERIFICATION_RESULT:
393 case TCG_PTS_INTEG_REPORT:
394 /* On Windows only*/
395 case TCG_PTS_WIN_FILE_META:
396 case TCG_PTS_REGISTRY_VALUE:
397 /* Received on IMC side only*/
398 case TCG_PTS_REQ_PROTO_CAPS:
399 case TCG_PTS_DH_NONCE_PARAMS_REQ:
400 case TCG_PTS_DH_NONCE_FINISH:
401 case TCG_PTS_MEAS_ALGO:
402 case TCG_PTS_GET_TPM_VERSION_INFO:
403 case TCG_PTS_REQ_TEMPL_REF_MANI_SET_META:
404 case TCG_PTS_UPDATE_TEMPL_REF_MANI:
405 case TCG_PTS_GET_AIK:
406 case TCG_PTS_REQ_FUNC_COMP_EVID:
407 case TCG_PTS_GEN_ATTEST_EVID:
408 case TCG_PTS_REQ_FILE_META:
409 case TCG_PTS_REQ_FILE_MEAS:
410 case TCG_PTS_REQ_INTEG_MEAS_LOG:
411 default:
412 DBG1(DBG_IMV, "received unsupported attribute '%N'",
413 tcg_attr_names, attr->get_type(attr));
414 break;
415 }
416 return TRUE;
417 }
418