1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
|
/*
* Copyright 2007-2020 The OpenSSL Project Authors. All Rights Reserved.
* Copyright Nokia 2007-2020
* Copyright Siemens AG 2015-2020
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/* CMP functions for PKIMessage checking */
#include "cmp_local.h"
#include <openssl/cmp_util.h>
/* explicit #includes not strictly needed since implied by the above: */
#include <openssl/asn1t.h>
#include <openssl/cmp.h>
#include <openssl/crmf.h>
#include <openssl/err.h>
#include <openssl/x509.h>
#include "crypto/x509.h"
/* Verify a message protected by signature according to RFC section 5.1.3.3 */
static int verify_signature(const OSSL_CMP_CTX *cmp_ctx,
const OSSL_CMP_MSG *msg, X509 *cert)
{
OSSL_CMP_PROTECTEDPART prot_part;
EVP_PKEY *pubkey = NULL;
BIO *bio = BIO_new(BIO_s_mem()); /* may be NULL */
int res = 0;
if (!ossl_assert(cmp_ctx != NULL && msg != NULL && cert != NULL))
return 0;
/* verify that keyUsage, if present, contains digitalSignature */
if (!cmp_ctx->ignore_keyusage
&& (X509_get_key_usage(cert) & X509v3_KU_DIGITAL_SIGNATURE) == 0) {
CMPerr(0, CMP_R_MISSING_KEY_USAGE_DIGITALSIGNATURE);
goto sig_err;
}
pubkey = X509_get_pubkey(cert);
if (pubkey == NULL) {
CMPerr(0, CMP_R_FAILED_EXTRACTING_PUBKEY);
goto sig_err;
}
prot_part.header = msg->header;
prot_part.body = msg->body;
if (ASN1_item_verify_ex(ASN1_ITEM_rptr(OSSL_CMP_PROTECTEDPART),
msg->header->protectionAlg, msg->protection,
&prot_part, NULL, pubkey, cmp_ctx->libctx,
cmp_ctx->propq) > 0) {
res = 1;
goto end;
}
sig_err:
res = x509_print_ex_brief(bio, cert, X509_FLAG_NO_EXTENSIONS);
CMPerr(0, CMP_R_ERROR_VALIDATING_SIGNATURE);
if (res)
ERR_add_error_mem_bio("\n", bio);
res = 0;
end:
EVP_PKEY_free(pubkey);
BIO_free(bio);
return res;
}
/* Verify a message protected with PBMAC */
static int verify_PBMAC(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg)
{
ASN1_BIT_STRING *protection = NULL;
int valid = 0;
/* generate expected protection for the message */
if ((protection = ossl_cmp_calc_protection(ctx, msg)) == NULL)
return 0; /* failed to generate protection string! */
valid = msg->protection != NULL && msg->protection->length >= 0
&& msg->protection->type == protection->type
&& msg->protection->length == protection->length
&& CRYPTO_memcmp(msg->protection->data, protection->data,
protection->length) == 0;
ASN1_BIT_STRING_free(protection);
if (!valid)
CMPerr(0, CMP_R_WRONG_PBM_VALUE);
return valid;
}
/*-
* Attempt to validate certificate and path using any given store with trusted
* certs (possibly including CRLs and a cert verification callback function)
* and non-trusted intermediate certs from the given ctx.
*
* Returns 1 on successful validation and 0 otherwise.
*/
int OSSL_CMP_validate_cert_path(const OSSL_CMP_CTX *ctx,
X509_STORE *trusted_store, X509 *cert)
{
int valid = 0;
X509_STORE_CTX *csc = NULL;
int err;
if (ctx == NULL || cert == NULL) {
CMPerr(0, CMP_R_NULL_ARGUMENT);
return 0;
}
if (trusted_store == NULL) {
CMPerr(0, CMP_R_MISSING_TRUST_STORE);
return 0;
}
if ((csc = X509_STORE_CTX_new_ex(ctx->libctx, ctx->propq)) == NULL
|| !X509_STORE_CTX_init(csc, trusted_store,
cert, ctx->untrusted))
goto err;
valid = X509_verify_cert(csc) > 0;
/* make sure suitable error is queued even if callback did not do */
err = ERR_peek_last_error();
if (!valid && ERR_GET_REASON(err) != CMP_R_POTENTIALLY_INVALID_CERTIFICATE)
CMPerr(0, CMP_R_POTENTIALLY_INVALID_CERTIFICATE);
err:
/* directly output any fresh errors, needed for check_msg_find_cert() */
OSSL_CMP_CTX_print_errors(ctx);
X509_STORE_CTX_free(csc);
return valid;
}
/* Return 0 if expect_name != NULL and there is no matching actual_name */
static int check_name(const OSSL_CMP_CTX *ctx, int log_success,
const char *actual_desc, const X509_NAME *actual_name,
const char *expect_desc, const X509_NAME *expect_name)
{
char *str;
if (expect_name == NULL)
return 1; /* no expectation, thus trivially fulfilled */
/* make sure that a matching name is there */
if (actual_name == NULL) {
ossl_cmp_log1(WARN, ctx, "missing %s", actual_desc);
return 0;
}
str = X509_NAME_oneline(actual_name, NULL, 0);
if (X509_NAME_cmp(actual_name, expect_name) == 0) {
if (log_success && str != NULL)
ossl_cmp_log2(INFO, ctx, " subject matches %s: %s", expect_desc,
str);
OPENSSL_free(str);
return 1;
}
if (str != NULL)
ossl_cmp_log2(INFO, ctx, " actual name in %s = %s", actual_desc, str);
OPENSSL_free(str);
if ((str = X509_NAME_oneline(expect_name, NULL, 0)) != NULL)
ossl_cmp_log2(INFO, ctx, " does not match %s = %s", expect_desc, str);
OPENSSL_free(str);
return 0;
}
/* Return 0 if skid != NULL and there is no matching subject key ID in cert */
static int check_kid(const OSSL_CMP_CTX *ctx,
const ASN1_OCTET_STRING *ckid,
const ASN1_OCTET_STRING *skid)
{
char *str;
if (skid == NULL)
return 1; /* no expectation, thus trivially fulfilled */
/* make sure that the expected subject key identifier is there */
if (ckid == NULL) {
ossl_cmp_warn(ctx, "missing Subject Key Identifier in certificate");
return 0;
}
str = OPENSSL_buf2hexstr(ckid->data, ckid->length);
if (ASN1_OCTET_STRING_cmp(ckid, skid) == 0) {
if (str != NULL)
ossl_cmp_log1(INFO, ctx, " subjectKID matches senderKID: %s", str);
OPENSSL_free(str);
return 1;
}
if (str != NULL)
ossl_cmp_log1(INFO, ctx, " cert Subject Key Identifier = %s", str);
OPENSSL_free(str);
if ((str = OPENSSL_buf2hexstr(skid->data, skid->length)) != NULL)
ossl_cmp_log1(INFO, ctx, " does not match senderKID = %s", str);
OPENSSL_free(str);
return 0;
}
static int already_checked(const X509 *cert,
const STACK_OF(X509) *already_checked)
{
int i;
for (i = sk_X509_num(already_checked /* may be NULL */); i > 0; i--)
if (X509_cmp(sk_X509_value(already_checked, i - 1), cert) == 0)
return 1;
return 0;
}
/*-
* Check if the given cert is acceptable as sender cert of the given message.
* The subject DN must match, the subject key ID as well if present in the msg,
* and the cert must be current (checked if ctx->trusted is not NULL).
* Note that cert revocation etc. is checked by OSSL_CMP_validate_cert_path().
*
* Returns 0 on error or not acceptable, else 1.
*/
static int cert_acceptable(const OSSL_CMP_CTX *ctx,
const char *desc1, const char *desc2, X509 *cert,
const STACK_OF(X509) *already_checked1,
const STACK_OF(X509) *already_checked2,
const OSSL_CMP_MSG *msg)
{
X509_STORE *ts = ctx->trusted;
int self_issued = X509_check_issued(cert, cert) == X509_V_OK;
char *str;
X509_VERIFY_PARAM *vpm = ts != NULL ? X509_STORE_get0_param(ts) : NULL;
int time_cmp;
ossl_cmp_log3(INFO, ctx, " considering %s%s %s with..",
self_issued ? "self-issued ": "", desc1, desc2);
if ((str = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0)) != NULL)
ossl_cmp_log1(INFO, ctx, " subject = %s", str);
OPENSSL_free(str);
if (!self_issued) {
str = X509_NAME_oneline(X509_get_issuer_name(cert), NULL, 0);
if (str != NULL)
ossl_cmp_log1(INFO, ctx, " issuer = %s", str);
OPENSSL_free(str);
}
if (already_checked(cert, already_checked1)
|| already_checked(cert, already_checked2)) {
ossl_cmp_info(ctx, " cert has already been checked");
return 0;
}
time_cmp = X509_cmp_timeframe(vpm, X509_get0_notBefore(cert),
X509_get0_notAfter(cert));
if (time_cmp != 0) {
ossl_cmp_warn(ctx, time_cmp > 0 ? "cert has expired"
: "cert is not yet valid");
return 0;
}
if (!check_name(ctx, 1,
"cert subject", X509_get_subject_name(cert),
"sender field", msg->header->sender->d.directoryName))
return 0;
if (!check_kid(ctx, X509_get0_subject_key_id(cert), msg->header->senderKID))
return 0;
/* prevent misleading error later in case x509v3_cache_extensions() fails */
if (!x509v3_cache_extensions(cert)) {
ossl_cmp_warn(ctx, "cert appears to be invalid");
return 0;
}
if (!verify_signature(ctx, msg, cert)) {
ossl_cmp_warn(ctx, "msg signature verification failed");
return 0;
}
/* acceptable also if there is no senderKID in msg header */
ossl_cmp_info(ctx, " cert seems acceptable");
return 1;
}
static int check_cert_path(const OSSL_CMP_CTX *ctx, X509_STORE *store,
X509 *scrt)
{
if (OSSL_CMP_validate_cert_path(ctx, store, scrt))
return 1;
ossl_cmp_warn(ctx,
"msg signature validates but cert path validation failed");
return 0;
}
/*
* Exceptional handling for 3GPP TS 33.310 [3G/LTE Network Domain Security
* (NDS); Authentication Framework (AF)], only to use for IP messages
* and if the ctx option is explicitly set: use self-issued certificates
* from extraCerts as trust anchor to validate sender cert -
* provided it also can validate the newly enrolled certificate
*/
static int check_cert_path_3gpp(const OSSL_CMP_CTX *ctx,
const OSSL_CMP_MSG *msg, X509 *scrt)
{
int valid = 0;
X509_STORE *store;
if (!ctx->permitTAInExtraCertsForIR)
return 0;
if ((store = X509_STORE_new()) == NULL
|| !ossl_cmp_X509_STORE_add1_certs(store, msg->extraCerts,
1 /* self-issued only */))
goto err;
/* store does not include CRLs */
valid = OSSL_CMP_validate_cert_path(ctx, store, scrt);
if (!valid) {
ossl_cmp_warn(ctx,
"also exceptional 3GPP mode cert path validation failed");
} else {
/*
* verify that the newly enrolled certificate (which assumed rid ==
* OSSL_CMP_CERTREQID) can also be validated with the same trusted store
*/
EVP_PKEY *pkey = OSSL_CMP_CTX_get0_newPkey(ctx, 1);
OSSL_CMP_CERTRESPONSE *crep =
ossl_cmp_certrepmessage_get0_certresponse(msg->body->value.ip,
OSSL_CMP_CERTREQID);
X509 *newcrt = ossl_cmp_certresponse_get1_cert(crep, ctx, pkey);
/*
* maybe better use get_cert_status() from cmp_client.c, which catches
* errors
*/
valid = OSSL_CMP_validate_cert_path(ctx, store, newcrt);
X509_free(newcrt);
}
err:
X509_STORE_free(store);
return valid;
}
static int check_msg_given_cert(const OSSL_CMP_CTX *ctx, X509 *cert,
const OSSL_CMP_MSG *msg)
{
return cert_acceptable(ctx, "previously validated", "sender cert",
cert, NULL, NULL, msg)
&& (check_cert_path(ctx, ctx->trusted, cert)
|| check_cert_path_3gpp(ctx, msg, cert));
}
/*-
* Try all certs in given list for verifying msg, normally or in 3GPP mode.
* If already_checked1 == NULL then certs are assumed to be the msg->extraCerts.
* On success cache the found cert using ossl_cmp_ctx_set0_validatedSrvCert().
*/
static int check_msg_with_certs(OSSL_CMP_CTX *ctx, const STACK_OF(X509) *certs,
const char *desc,
const STACK_OF(X509) *already_checked1,
const STACK_OF(X509) *already_checked2,
const OSSL_CMP_MSG *msg, int mode_3gpp)
{
int in_extraCerts = already_checked1 == NULL;
int n_acceptable_certs = 0;
int i;
if (sk_X509_num(certs) <= 0) {
ossl_cmp_log1(WARN, ctx, "no %s", desc);
return 0;
}
for (i = 0; i < sk_X509_num(certs); i++) { /* certs may be NULL */
X509 *cert = sk_X509_value(certs, i);
if (!ossl_assert(cert != NULL))
return 0;
if (!cert_acceptable(ctx, "cert from", desc, cert,
already_checked1, already_checked2, msg))
continue;
n_acceptable_certs++;
if (mode_3gpp ? check_cert_path_3gpp(ctx, msg, cert)
: check_cert_path(ctx, ctx->trusted, cert)) {
/* store successful sender cert for further msgs in transaction */
if (!X509_up_ref(cert))
return 0;
if (!ossl_cmp_ctx_set0_validatedSrvCert(ctx, cert)) {
X509_free(cert);
return 0;
}
return 1;
}
}
if (in_extraCerts && n_acceptable_certs == 0)
ossl_cmp_warn(ctx, "no acceptable cert in extraCerts");
return 0;
}
/*-
* Verify msg trying first ctx->untrusted, which should include extraCerts
* at its front, then trying the trusted certs in truststore (if any) of ctx.
* On success cache the found cert using ossl_cmp_ctx_set0_validatedSrvCert().
*/
static int check_msg_all_certs(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg,
int mode_3gpp)
{
int ret = 0;
if (mode_3gpp
&& ((!ctx->permitTAInExtraCertsForIR
|| ossl_cmp_msg_get_bodytype(msg) != OSSL_CMP_PKIBODY_IP)))
return 0;
ossl_cmp_info(ctx,
mode_3gpp ? "normal mode failed; trying now 3GPP mode trusting extraCerts"
: "trying first normal mode using trust store");
if (check_msg_with_certs(ctx, msg->extraCerts, "extraCerts",
NULL, NULL, msg, mode_3gpp))
return 1;
if (check_msg_with_certs(ctx, ctx->untrusted, "untrusted certs",
msg->extraCerts, NULL, msg, mode_3gpp))
return 1;
if (ctx->trusted == NULL) {
ossl_cmp_warn(ctx, mode_3gpp ? "no self-issued extraCerts"
: "no trusted store");
} else {
STACK_OF(X509) *trusted = X509_STORE_get1_all_certs(ctx->trusted);
ret = check_msg_with_certs(ctx, trusted,
mode_3gpp ? "self-issued extraCerts"
: "certs in trusted store",
msg->extraCerts, ctx->untrusted,
msg, mode_3gpp);
sk_X509_pop_free(trusted, X509_free);
}
return ret;
}
static int no_log_cb(const char *func, const char *file, int line,
OSSL_CMP_severity level, const char *msg)
{
return 1;
}
/*-
* Verify message signature with any acceptable and valid candidate cert.
* On success cache the found cert using ossl_cmp_ctx_set0_validatedSrvCert().
*/
static int check_msg_find_cert(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg)
{
X509 *scrt = ctx->validatedSrvCert; /* previous successful sender cert */
GENERAL_NAME *sender = msg->header->sender;
char *sname = NULL;
char *skid_str = NULL;
const ASN1_OCTET_STRING *skid = msg->header->senderKID;
OSSL_CMP_log_cb_t backup_log_cb = ctx->log_cb;
int res = 0;
if (sender == NULL || msg->body == NULL)
return 0; /* other NULL cases already have been checked */
if (sender->type != GEN_DIRNAME) {
CMPerr(0, CMP_R_SENDER_GENERALNAME_TYPE_NOT_SUPPORTED);
return 0;
}
/* dump any hitherto errors to avoid confusion when printing further ones */
OSSL_CMP_CTX_print_errors(ctx);
/* enable clearing irrelevant errors in attempts to validate sender certs */
(void)ERR_set_mark();
ctx->log_cb = no_log_cb; /* temporarily disable logging */
/*
* try first cached scrt, used successfully earlier in same transaction,
* for validating this and any further msgs where extraCerts may be left out
*/
if (scrt != NULL) {
if (check_msg_given_cert(ctx, scrt, msg)) {
ctx->log_cb = backup_log_cb;
(void)ERR_pop_to_mark();
return 1;
}
/* cached sender cert has shown to be no more successfully usable */
(void)ossl_cmp_ctx_set0_validatedSrvCert(ctx, NULL);
/* re-do the above check (just) for adding diagnostic information */
ossl_cmp_info(ctx,
"trying to verify msg signature with previously validated cert");
(void)check_msg_given_cert(ctx, scrt, msg);
}
res = check_msg_all_certs(ctx, msg, 0 /* using ctx->trusted */)
|| check_msg_all_certs(ctx, msg, 1 /* 3gpp */);
ctx->log_cb = backup_log_cb;
if (res) {
/* discard any diagnostic information on trying to use certs */
(void)ERR_pop_to_mark();
goto end;
}
/* failed finding a sender cert that verifies the message signature */
(void)ERR_clear_last_mark();
sname = X509_NAME_oneline(sender->d.directoryName, NULL, 0);
skid_str = skid == NULL ? NULL
: OPENSSL_buf2hexstr(skid->data, skid->length);
if (ctx->log_cb != NULL) {
ossl_cmp_info(ctx, "trying to verify msg signature with a valid cert that..");
if (sname != NULL)
ossl_cmp_log1(INFO, ctx, "matches msg sender = %s", sname);
if (skid_str != NULL)
ossl_cmp_log1(INFO, ctx, "matches msg senderKID = %s", skid_str);
else
ossl_cmp_info(ctx, "while msg header does not contain senderKID");
/* re-do the above checks (just) for adding diagnostic information */
(void)check_msg_all_certs(ctx, msg, 0 /* using ctx->trusted */);
(void)check_msg_all_certs(ctx, msg, 1 /* 3gpp */);
}
CMPerr(0, CMP_R_NO_SUITABLE_SENDER_CERT);
if (sname != NULL) {
ERR_add_error_txt(NULL, "for msg sender name = ");
ERR_add_error_txt(NULL, sname);
}
if (skid_str != NULL) {
ERR_add_error_txt(" and ", "for msg senderKID = ");
ERR_add_error_txt(NULL, skid_str);
}
end:
OPENSSL_free(sname);
OPENSSL_free(skid_str);
return res;
}
/*-
* Validate the protection of the given PKIMessage using either password-
* based mac (PBM) or a signature algorithm. In the case of signature algorithm,
* the sender certificate can have been pinned by providing it in ctx->srvCert,
* else it is searched in msg->extraCerts, ctx->untrusted, in ctx->trusted
* (in this order) and is path is validated against ctx->trusted.
* On success cache the found cert using ossl_cmp_ctx_set0_validatedSrvCert().
*
* If ctx->permitTAInExtraCertsForIR is true and when validating a CMP IP msg,
* the trust anchor for validating the IP msg may be taken from msg->extraCerts
* if a self-issued certificate is found there that can be used to
* validate the enrolled certificate returned in the IP.
* This is according to the need given in 3GPP TS 33.310.
*
* Returns 1 on success, 0 on error or validation failed.
*/
int OSSL_CMP_validate_msg(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg)
{
X509 *scrt;
ossl_cmp_debug(ctx, "validating CMP message");
if (ctx == NULL || msg == NULL
|| msg->header == NULL || msg->body == NULL) {
CMPerr(0, CMP_R_NULL_ARGUMENT);
return 0;
}
if (msg->header->protectionAlg == NULL /* unprotected message */
|| msg->protection == NULL || msg->protection->data == NULL) {
CMPerr(0, CMP_R_MISSING_PROTECTION);
return 0;
}
switch (ossl_cmp_hdr_get_protection_nid(msg->header)) {
/* 5.1.3.1. Shared Secret Information */
case NID_id_PasswordBasedMAC:
if (ctx->secretValue == NULL) {
ossl_cmp_warn(ctx, "no secret available for verifying PBM-based CMP message protection");
return 1;
}
if (verify_PBMAC(ctx, msg)) {
/*
* RFC 4210, 5.3.2: 'Note that if the PKI Message Protection is
* "shared secret information", then any certificate transported in
* the caPubs field may be directly trusted as a root CA
* certificate by the initiator.'
*/
switch (ossl_cmp_msg_get_bodytype(msg)) {
case -1:
return 0;
case OSSL_CMP_PKIBODY_IP:
case OSSL_CMP_PKIBODY_CP:
case OSSL_CMP_PKIBODY_KUP:
case OSSL_CMP_PKIBODY_CCP:
if (ctx->trusted != NULL) {
STACK_OF(X509) *certs = msg->body->value.ip->caPubs;
/* value.ip is same for cp, kup, and ccp */
if (!ossl_cmp_X509_STORE_add1_certs(ctx->trusted, certs, 0))
/* adds both self-issued and not self-issued certs */
return 0;
}
break;
default:
break;
}
ossl_cmp_debug(ctx,
"sucessfully validated PBM-based CMP message protection");
return 1;
}
ossl_cmp_warn(ctx, "verifying PBM-based CMP message protection failed");
break;
/*
* 5.1.3.2 DH Key Pairs
* Not yet supported
*/
case NID_id_DHBasedMac:
CMPerr(0, CMP_R_UNSUPPORTED_PROTECTION_ALG_DHBASEDMAC);
break;
/*
* 5.1.3.3. Signature
*/
default:
scrt = ctx->srvCert;
if (scrt == NULL) {
if (ctx->trusted == NULL) {
ossl_cmp_warn(ctx, "no trust store nor pinned server cert available for verifying signature-based CMP message protection");
return 1;
}
if (check_msg_find_cert(ctx, msg))
return 1;
} else { /* use pinned sender cert */
/* use ctx->srvCert for signature check even if not acceptable */
if (verify_signature(ctx, msg, scrt)) {
ossl_cmp_debug(ctx,
"sucessfully validated signature-based CMP message protection");
return 1;
}
ossl_cmp_warn(ctx, "CMP message signature verification failed");
CMPerr(0, CMP_R_SRVCERT_DOES_NOT_VALIDATE_MSG);
}
break;
}
return 0;
}
/*-
* Check received message (i.e., response by server or request from client)
* Any msg->extraCerts are prepended to ctx->untrusted.
*
* Ensures that:
* its sender is of appropriate type (curently only X509_NAME) and
* matches any expected sender or srvCert subject given in the ctx
* it has a valid body type
* its protection is valid (or invalid/absent, but only if a callback function
* is present and yields a positive result using also the supplied argument)
* its transaction ID matches the previous transaction ID stored in ctx (if any)
* its recipNonce matches the previous senderNonce stored in the ctx (if any)
*
* If everything is fine:
* learns the senderNonce from the received message,
* learns the transaction ID if it is not yet in ctx,
* and makes any certs in caPubs directly trusted.
*
* Returns 1 on success, 0 on error.
*/
int ossl_cmp_msg_check_update(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg,
ossl_cmp_allow_unprotected_cb_t cb, int cb_arg)
{
OSSL_CMP_PKIHEADER *hdr;
const X509_NAME *expected_sender;
if (!ossl_assert(ctx != NULL && msg != NULL && msg->header != NULL))
return 0;
hdr = OSSL_CMP_MSG_get0_header(msg);
/* validate sender name of received msg */
if (hdr->sender->type != GEN_DIRNAME) {
CMPerr(0, CMP_R_SENDER_GENERALNAME_TYPE_NOT_SUPPORTED);
return 0; /* TODO FR#42: support for more than X509_NAME */
}
/*
* Compare actual sender name of response with expected sender name.
* Mitigates risk to accept misused PBM secret
* or misused certificate of an unauthorized entity of a trusted hierarchy.
*/
expected_sender = ctx->expected_sender;
if (expected_sender == NULL && ctx->srvCert != NULL)
expected_sender = X509_get_subject_name(ctx->srvCert);
if (!check_name(ctx, 0, "sender DN field", hdr->sender->d.directoryName,
"expected sender", expected_sender))
return 0;
/* Note: if recipient was NULL-DN it could be learned here if needed */
if (sk_X509_num(msg->extraCerts) > 10)
ossl_cmp_warn(ctx,
"received CMP message contains more than 10 extraCerts");
/*
* Store any provided extraCerts in ctx for use in OSSL_CMP_validate_msg()
* and for future use, such that they are available to ctx->certConf_cb and
* the peer does not need to send them again in the same transaction.
* Note that it does not help validating the message before storing the
* extraCerts because they do not belong to the protected msg part anyway.
* For efficiency, the extraCerts are prepended so they get used first.
*/
if (!X509_add_certs(ctx->untrusted, msg->extraCerts,
/* this allows self-signed certs */
X509_ADD_FLAG_UP_REF | X509_ADD_FLAG_NO_DUP
| X509_ADD_FLAG_PREPEND))
return 0;
/* validate message protection */
if (hdr->protectionAlg != NULL) {
/* detect explicitly permitted exceptions for invalid protection */
if (!OSSL_CMP_validate_msg(ctx, msg)
&& (cb == NULL || (*cb)(ctx, msg, 1, cb_arg) <= 0)) {
#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
CMPerr(0, CMP_R_ERROR_VALIDATING_PROTECTION);
return 0;
#endif
}
} else {
/* detect explicitly permitted exceptions for missing protection */
if (cb == NULL || (*cb)(ctx, msg, 0, cb_arg) <= 0) {
#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
CMPerr(0, CMP_R_MISSING_PROTECTION);
return 0;
#endif
}
}
/* check CMP version number in header */
if (ossl_cmp_hdr_get_pvno(hdr) != OSSL_CMP_PVNO) {
#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
CMPerr(0, CMP_R_UNEXPECTED_PVNO);
return 0;
#endif
}
if (ossl_cmp_msg_get_bodytype(msg) < 0) {
#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
CMPerr(0, CMP_R_PKIBODY_ERROR);
return 0;
#endif
}
/* compare received transactionID with the expected one in previous msg */
if (ctx->transactionID != NULL
&& (hdr->transactionID == NULL
|| ASN1_OCTET_STRING_cmp(ctx->transactionID,
hdr->transactionID) != 0)) {
#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
CMPerr(0, CMP_R_TRANSACTIONID_UNMATCHED);
return 0;
#endif
}
/* compare received nonce with the one we sent */
if (ctx->senderNonce != NULL
&& (msg->header->recipNonce == NULL
|| ASN1_OCTET_STRING_cmp(ctx->senderNonce,
hdr->recipNonce) != 0)) {
#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
CMPerr(0, CMP_R_RECIPNONCE_UNMATCHED);
return 0;
#endif
}
/*
* RFC 4210 section 5.1.1 states: the recipNonce is copied from
* the senderNonce of the previous message in the transaction.
* --> Store for setting in next message
*/
if (!ossl_cmp_ctx_set1_recipNonce(ctx, hdr->senderNonce))
return 0;
/* if not yet present, learn transactionID */
if (ctx->transactionID == NULL
&& !OSSL_CMP_CTX_set1_transactionID(ctx, hdr->transactionID))
return -1;
/*
* Store any provided extraCerts in ctx for future use,
* such that they are available to ctx->certConf_cb and
* the peer does not need to send them again in the same transaction.
* For efficiency, the extraCerts are prepended so they get used first.
*/
if (!X509_add_certs(ctx->untrusted, msg->extraCerts,
/* this allows self-signed certs */
X509_ADD_FLAG_UP_REF | X509_ADD_FLAG_NO_DUP
| X509_ADD_FLAG_PREPEND))
return -1;
if (ossl_cmp_hdr_get_protection_nid(hdr) == NID_id_PasswordBasedMAC) {
/*
* RFC 4210, 5.3.2: 'Note that if the PKI Message Protection is
* "shared secret information", then any certificate transported in
* the caPubs field may be directly trusted as a root CA
* certificate by the initiator.'
*/
switch (ossl_cmp_msg_get_bodytype(msg)) {
case OSSL_CMP_PKIBODY_IP:
case OSSL_CMP_PKIBODY_CP:
case OSSL_CMP_PKIBODY_KUP:
case OSSL_CMP_PKIBODY_CCP:
if (ctx->trusted != NULL) {
STACK_OF(X509) *certs = msg->body->value.ip->caPubs;
/* value.ip is same for cp, kup, and ccp */
if (!ossl_cmp_X509_STORE_add1_certs(ctx->trusted, certs, 0))
/* adds both self-issued and not self-issued certs */
return 0;
}
break;
default:
break;
}
}
return 1;
}
int ossl_cmp_verify_popo(const OSSL_CMP_CTX *ctx,
const OSSL_CMP_MSG *msg, int acceptRAVerified)
{
if (!ossl_assert(msg != NULL && msg->body != NULL))
return 0;
switch (msg->body->type) {
case OSSL_CMP_PKIBODY_P10CR:
{
X509_REQ *req = msg->body->value.p10cr;
if (X509_REQ_verify_ex(req, X509_REQ_get0_pubkey(req), ctx->libctx,
ctx->propq) <= 0) {
#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
CMPerr(0, CMP_R_REQUEST_NOT_ACCEPTED);
return 0;
#endif
}
}
break;
case OSSL_CMP_PKIBODY_IR:
case OSSL_CMP_PKIBODY_CR:
case OSSL_CMP_PKIBODY_KUR:
if (!OSSL_CRMF_MSGS_verify_popo(msg->body->value.ir, OSSL_CMP_CERTREQID,
acceptRAVerified,
ctx->libctx, ctx->propq)) {
#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
return 0;
#endif
}
break;
default:
CMPerr(0, CMP_R_PKIBODY_ERROR);
return 0;
}
return 1;
}
|