Repository navigation
Expand file tree
/
Copy pathssl_engine_kernel.c
More file actions
2808 lines (2463 loc) · 102 KB
/
Copy pathssl_engine_kernel.c
File metadata and controls
2808 lines (2463 loc) · 102 KB
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
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* _ _
* _ __ ___ ___ __| | ___ ___| | mod_ssl
* | '_ ` _ \ / _ \ / _` | / __/ __| | Apache Interface to OpenSSL
* | | | | | | (_) | (_| | \__ \__ \ |
* |_| |_| |_|\___/ \__,_|___|___/___/_|
* |_____|
* ssl_engine_kernel.c
* The SSL engine kernel
*/
/* ``It took me fifteen years to discover
I had no talent for programming, but
I couldn't give it up because by that
time I was too famous.''
-- Unknown */
#include "ssl_private.h"
#include "httpd.h"
#include "mod_ssl.h"
#include "util_md5.h"
#include "scoreboard.h"
#ifdef HAVE_OPENSSL_ECH
#include <openssl/ech.h>
#endif
static void ssl_configure_env(request_rec *r, SSLConnRec *sslconn);
#ifdef HAVE_TLSEXT
static int ssl_find_vhost(void *servername, conn_rec *c, server_rec *s);
#endif
/* Perform a speculative (and non-blocking) read from the connection
* filters for the given request, to determine whether there is any
* pending data to read. Return non-zero if there is, else zero. */
static int has_buffered_data(request_rec *r)
{
apr_bucket_brigade *bb;
apr_off_t len;
apr_status_t rv;
int result;
bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
rv = ap_get_brigade(r->connection->input_filters, bb, AP_MODE_SPECULATIVE,
APR_NONBLOCK_READ, 1);
result = rv == APR_SUCCESS
&& apr_brigade_length(bb, 1, &len) == APR_SUCCESS
&& len > 0;
apr_brigade_destroy(bb);
return result;
}
/* If a renegotiation is required for the location, and the request
* includes a message body (and the client has not requested a "100
* Continue" response), then the client will be streaming the request
* body over the wire already. In that case, it is not possible to
* stop and perform a new SSL handshake immediately; once the SSL
* library moves to the "accept" state, it will reject the SSL packets
* which the client is sending for the request body.
*
* To allow authentication to complete in the hook, the solution used
* here is to fill a (bounded) buffer with the request body, and then
* to reinject that request body later.
*
* This function is called to fill the renegotiation buffer for the
* location as required, or fail. Returns zero on success or HTTP_
* error code on failure.
*/
static int fill_reneg_buffer(request_rec *r, SSLDirConfigRec *dc)
{
int rv;
apr_size_t rsize;
/* ### this is HTTP/1.1 specific, special case for protocol? */
if (r->expecting_100 || !ap_request_has_body(r)) {
return 0;
}
rsize = dc->nRenegBufferSize == UNSET ? DEFAULT_RENEG_BUFFER_SIZE : dc->nRenegBufferSize;
if (rsize > 0) {
/* Fill the I/O buffer with the request body if possible. */
rv = ssl_io_buffer_fill(r, rsize);
}
else {
/* If the reneg buffer size is set to zero, just fail. */
rv = HTTP_REQUEST_ENTITY_TOO_LARGE;
}
return rv;
}
#ifdef HAVE_TLSEXT
/* Check whether a transition from vhost sc1 to sc2 from SNI to Host:
* vhost selection is permitted according to the SSLVHostSNIPolicy
* setting. Returns 1 if the policy treats the vhosts as compatible,
* else 0. */
static int ssl_check_vhost_sni_policy(SSLSrvConfigRec *sc1,
SSLSrvConfigRec *sc2)
{
modssl_snivhpolicy_t policy = sc1->mc->snivh_policy;
/* Policy: insecure => allow everything. */
if (policy == MODSSL_SNIVH_INSECURE)
return 1;
/* Policy: strict => fail for any vhost transition. */
if (policy == MODSSL_SNIVH_STRICT)
return sc1 == sc2;
/* For authonly/secure policy, compare the hash. */
AP_DEBUG_ASSERT(sc1->sni_policy_hash);
AP_DEBUG_ASSERT(sc2->sni_policy_hash);
return strcmp(sc1->sni_policy_hash, sc2->sni_policy_hash) == 0;
}
#endif
/*
* Post Read Request Handler
*/
int ssl_hook_ReadReq(request_rec *r)
{
SSLSrvConfigRec *sc = mySrvConfig(r->server);
SSLConnRec *sslconn;
#ifdef HAVE_TLSEXT
const char *servername;
#endif
SSL *ssl;
/* If we are on a slave connection, we do not expect to have an SSLConnRec,
* but our master connection might. */
sslconn = myConnConfig(r->connection);
if (!(sslconn && sslconn->ssl) && r->connection->master) {
sslconn = myConnConfig(r->connection->master);
}
if (!sslconn) {
return DECLINED;
}
if (sslconn->service_unavailable) {
/* This is set when the SSL properties of this connection are
* incomplete or if this connection was made to challenge a
* particular hostname (ACME). We never serve any request on
* such a connection. */
/* TODO: a retry-after indicator would be nice here */
return HTTP_SERVICE_UNAVAILABLE;
}
if (sslconn->non_ssl_request == NON_SSL_SET_ERROR_MSG) {
apr_table_setn(r->notes, "error-notes",
"Reason: You're speaking plain HTTP to an SSL-enabled "
"server port.<br />\n Instead use the HTTPS scheme to "
"access this URL, please.<br />\n");
/* Now that we have caught this error, forget it. we are done
* with using SSL on this request.
*/
sslconn->non_ssl_request = NON_SSL_OK;
return HTTP_BAD_REQUEST;
}
/*
* Get the SSL connection structure and perform the
* delayed interlinking from SSL back to request_rec
*/
ssl = sslconn->ssl;
if (!ssl) {
return DECLINED;
}
#ifdef HAVE_TLSEXT
/*
* Perform SNI checks only on the initial request. In particular,
* if these checks detect a problem, the checks shouldn't return an
* error again when processing an ErrorDocument redirect for the
* original problem.
*/
if (r->proxyreq != PROXYREQ_PROXY && ap_is_initial_req(r)) {
server_rec *handshakeserver = sslconn->server;
SSLSrvConfigRec *hssc = mySrvConfig(handshakeserver);
AP_DEBUG_ASSERT(hssc);
if ((servername = SSL_get_servername(ssl, TLSEXT_NAMETYPE_host_name))) {
/* The SNI extension supplied a hostname; reject any
* request without a Host header. */
if (!r->hostname) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02031)
"Hostname %s provided via SNI, but no hostname"
" provided in HTTP request", servername);
return HTTP_BAD_REQUEST;
}
}
else if (((sc->strict_sni_vhost_check == SSL_ENABLED_TRUE)
|| hssc->strict_sni_vhost_check == SSL_ENABLED_TRUE)
&& r->connection->vhost_lookup_data) {
/*
* We are using a name based configuration here, but no hostname was
* provided via SNI. Don't allow that if are requested to do strict
* checking. Check whether this strict checking was set up either in the
* server config we used for handshaking or in our current server.
* This should avoid insecure configuration by accident.
*/
ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(02033)
"No hostname was provided via SNI for a name based"
" virtual host");
apr_table_setn(r->notes, "error-notes",
"Reason: The client software did not provide a "
"hostname using Server Name Indication (SNI), "
"which is required to access this server.<br />\n");
return HTTP_FORBIDDEN;
}
/* Enforce SSL SNI vhost compatibility policy: the virtual
* host selected for the connection (based on the SNI
* extension) must have a "compatible" SSL configuration with
* the one selected based on the Host: header. */
if (!ssl_check_vhost_sni_policy(sc, hssc)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02032)
"Hostname %s %s and hostname %s provided"
" via HTTP have no compatible SSL setup for policy '%s'",
servername ? servername : handshakeserver->server_hostname,
servername ? "provided via SNI" : "(default host as no SNI was provided)",
r->hostname, MODSSL_SNIVH_NAME(sc->mc->snivh_policy));
return HTTP_MISDIRECTED_REQUEST;
}
}
#endif
modssl_set_app_data2(ssl, r);
/*
* Log information about incoming HTTPS requests
*/
if (APLOGrinfo(r) && ap_is_initial_req(r)) {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02034)
"%s HTTPS request received for child %ld (server %s)",
(r->connection->keepalives <= 0 ?
"Initial (No.1)" :
apr_psprintf(r->pool, "Subsequent (No.%d)",
r->connection->keepalives+1)),
r->connection->id,
ssl_util_vhostid(r->pool, r->server));
}
/* SetEnvIf ssl-*-shutdown flags can only be per-server,
* so they won't change across keepalive requests
*/
if (sslconn->shutdown_type == SSL_SHUTDOWN_TYPE_UNSET) {
ssl_configure_env(r, sslconn);
}
return DECLINED;
}
/*
* Move SetEnvIf information from request_rec to conn_rec/BUFF
* to allow the close connection handler to use them.
*/
static void ssl_configure_env(request_rec *r, SSLConnRec *sslconn)
{
int i;
const apr_array_header_t *arr = apr_table_elts(r->subprocess_env);
const apr_table_entry_t *elts = (const apr_table_entry_t *)arr->elts;
sslconn->shutdown_type = SSL_SHUTDOWN_TYPE_STANDARD;
for (i = 0; i < arr->nelts; i++) {
const char *key = elts[i].key;
switch (*key) {
case 's':
/* being case-sensitive here.
* and not checking for the -shutdown since these are the only
* SetEnvIf "flags" we support
*/
if (!strncmp(key+1, "sl-", 3)) {
key += 4;
if (!strncmp(key, "unclean", 7)) {
sslconn->shutdown_type = SSL_SHUTDOWN_TYPE_UNCLEAN;
}
else if (!strncmp(key, "accurate", 8)) {
sslconn->shutdown_type = SSL_SHUTDOWN_TYPE_ACCURATE;
}
return; /* should only ever be one ssl-*-shutdown */
}
break;
}
}
}
static int ssl_check_post_client_verify(request_rec *r, SSLSrvConfigRec *sc,
SSLDirConfigRec *dc, SSLConnRec *sslconn,
SSL *ssl)
{
X509 *cert;
/*
* Remember the peer certificate's DN
*/
if ((cert = SSL_get_peer_certificate(ssl))) {
if (sslconn->client_cert) {
X509_free(sslconn->client_cert);
}
sslconn->client_cert = cert;
sslconn->client_dn = NULL;
}
/*
* Finally check for acceptable renegotiation results
*/
if ((dc->nVerifyClient != SSL_CVERIFY_NONE) ||
(sc->server->auth.verify_mode != SSL_CVERIFY_NONE)) {
BOOL do_verify = ((dc->nVerifyClient == SSL_CVERIFY_REQUIRE) ||
(sc->server->auth.verify_mode == SSL_CVERIFY_REQUIRE));
if (do_verify && (SSL_get_verify_result(ssl) != X509_V_OK)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02262)
"Re-negotiation handshake failed: "
"Client verification failed");
return HTTP_FORBIDDEN;
}
if (do_verify) {
if (cert == NULL) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02263)
"Re-negotiation handshake failed: "
"Client certificate missing");
return HTTP_FORBIDDEN;
}
}
}
return OK;
}
/*
* Access Handler, classic flavour, for SSL/TLS up to v1.2
* where everything can be renegotiated and no one is happy.
*/
static int ssl_hook_Access_classic(request_rec *r, SSLSrvConfigRec *sc, SSLDirConfigRec *dc,
SSLConnRec *sslconn, SSL *ssl)
{
server_rec *handshakeserver = sslconn ? sslconn->server : NULL;
SSLSrvConfigRec *hssc = handshakeserver? mySrvConfig(handshakeserver) : NULL;
SSL_CTX *ctx = ssl ? SSL_get_SSL_CTX(ssl) : NULL;
BOOL renegotiate = FALSE, renegotiate_quick = FALSE;
X509 *peercert;
X509_STORE *cert_store = NULL;
X509_STORE_CTX *cert_store_ctx;
STACK_OF(SSL_CIPHER) *cipher_list_old = NULL, *cipher_list = NULL;
const SSL_CIPHER *cipher = NULL;
int depth, verify_old, verify, n, rc;
const char *ncipher_suite;
#ifdef HAVE_SRP
/*
* Support for per-directory reconfigured SSL connection parameters
*
* We do not force any renegotiation if the user is already authenticated
* via SRP.
*
*/
if (SSL_get_srp_username(ssl)) {
return DECLINED;
}
#endif
/*
* Support for per-directory reconfigured SSL connection parameters.
*
* This is implemented by forcing an SSL renegotiation with the
* reconfigured parameter suite. But Apache's internal API processing
* makes our life very hard here, because when internal sub-requests occur
* we nevertheless should avoid multiple unnecessary SSL handshakes (they
* require extra network I/O and especially time to perform).
*
* But the optimization for filtering out the unnecessary handshakes isn't
* obvious and trivial. Especially because while Apache is in its
* sub-request processing the client could force additional handshakes,
* too. And these take place perhaps without our notice. So the only
* possibility is to explicitly _ask_ OpenSSL whether the renegotiation
* has to be performed or not. It has to performed when some parameters
* which were previously known (by us) are not those we've now
* reconfigured (as known by OpenSSL) or (in optimized way) at least when
* the reconfigured parameter suite is stronger (more restrictions) than
* the currently active one.
*/
/*
* Override of SSLCipherSuite
*
* We provide two options here:
*
* o The paranoid and default approach where we force a renegotiation when
* the cipher suite changed in _any_ way (which is straight-forward but
* often forces renegotiations too often and is perhaps not what the
* user actually wanted).
*
* o The optimized and still secure way where we force a renegotiation
* only if the currently active cipher is no longer contained in the
* reconfigured/new cipher suite. Any other changes are not important
* because it's the servers choice to select a cipher from the ones the
* client supports. So as long as the current cipher is still in the new
* cipher suite we're happy. Because we can assume we would have
* selected it again even when other (better) ciphers exists now in the
* new cipher suite. This approach is fine because the user explicitly
* has to enable this via ``SSLOptions +OptRenegotiate''. So we do no
* implicit optimizations.
*/
ncipher_suite = (dc->szCipherSuite?
dc->szCipherSuite : (r->server != handshakeserver)?
sc->server->auth.cipher_suite : NULL);
if (ncipher_suite && (!sslconn->cipher_suite
|| strcmp(ncipher_suite, sslconn->cipher_suite))) {
/* remember old state */
if (dc->nOptions & SSL_OPT_OPTRENEGOTIATE) {
cipher = SSL_get_current_cipher(ssl);
}
else {
cipher_list_old = (STACK_OF(SSL_CIPHER) *)SSL_get_ciphers(ssl);
if (cipher_list_old) {
cipher_list_old = sk_SSL_CIPHER_dup(cipher_list_old);
}
}
/* configure new state */
if (r->connection->master) {
/* TODO: this categorically fails changed cipher suite settings
* on slave connections. We could do better by
* - create a new SSL* from our SSL_CTX and set cipher suite there,
* and retrieve ciphers, free afterwards
* Modifying the SSL on a slave connection is no good.
*/
apr_table_setn(r->notes, "ssl-renegotiate-forbidden", "cipher-suite");
if (cipher_list_old) {
sk_SSL_CIPHER_free(cipher_list_old);
}
return HTTP_FORBIDDEN;
}
if (!SSL_set_cipher_list(ssl, ncipher_suite)) {
ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(02253)
"Unable to reconfigure (per-directory) "
"permitted SSL ciphers");
ssl_log_ssl_error(SSLLOG_MARK, APLOG_ERR, r->server);
if (cipher_list_old) {
sk_SSL_CIPHER_free(cipher_list_old);
}
return HTTP_FORBIDDEN;
}
/* determine whether a renegotiation has to be forced */
cipher_list = (STACK_OF(SSL_CIPHER) *)SSL_get_ciphers(ssl);
if (dc->nOptions & SSL_OPT_OPTRENEGOTIATE) {
/* optimized way */
if ((!cipher && cipher_list) ||
(cipher && !cipher_list))
{
renegotiate = TRUE;
}
else if (cipher && cipher_list &&
(sk_SSL_CIPHER_find(cipher_list, cipher) < 0))
{
renegotiate = TRUE;
}
}
else {
/* paranoid way */
if ((!cipher_list_old && cipher_list) ||
(cipher_list_old && !cipher_list))
{
renegotiate = TRUE;
}
else if (cipher_list_old && cipher_list) {
for (n = 0;
!renegotiate && (n < sk_SSL_CIPHER_num(cipher_list));
n++)
{
const SSL_CIPHER *value = sk_SSL_CIPHER_value(cipher_list, n);
if (sk_SSL_CIPHER_find(cipher_list_old, value) < 0) {
renegotiate = TRUE;
}
}
for (n = 0;
!renegotiate && (n < sk_SSL_CIPHER_num(cipher_list_old));
n++)
{
const SSL_CIPHER *value = sk_SSL_CIPHER_value(cipher_list_old, n);
if (sk_SSL_CIPHER_find(cipher_list, value) < 0) {
renegotiate = TRUE;
}
}
}
}
/* cleanup */
if (cipher_list_old) {
sk_SSL_CIPHER_free(cipher_list_old);
}
if (renegotiate) {
if (r->connection->master) {
/* The request causes renegotiation on a slave connection.
* This is not allowed since we might have concurrent requests
* on this connection.
*/
apr_table_setn(r->notes, "ssl-renegotiate-forbidden", "cipher-suite");
return HTTP_FORBIDDEN;
}
#ifdef SSL_OP_CIPHER_SERVER_PREFERENCE
if (sc->cipher_server_pref == TRUE) {
SSL_set_options(ssl, SSL_OP_CIPHER_SERVER_PREFERENCE);
}
#endif
/* tracing */
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02220)
"Reconfigured cipher suite will force renegotiation");
}
}
/*
* override of SSLVerifyClient
*
* We force a renegotiation if the reconfigured/new verify type is
* stronger than the currently active verify type.
*
* The order is: none << optional_no_ca << optional << require
*
* Additionally the following optimization is possible here: When the
* currently active verify type is "none" but a client certificate is
* already known/present, it's enough to manually force a client
* verification but at least skip the I/O-intensive renegotiation
* handshake.
*/
if ((dc->nVerifyClient != SSL_CVERIFY_UNSET) ||
(sc->server->auth.verify_mode != SSL_CVERIFY_UNSET)) {
/* remember old state */
verify_old = SSL_get_verify_mode(ssl);
/* configure new state */
verify = SSL_VERIFY_NONE;
if ((dc->nVerifyClient == SSL_CVERIFY_REQUIRE) ||
(sc->server->auth.verify_mode == SSL_CVERIFY_REQUIRE)) {
verify |= SSL_VERIFY_PEER_STRICT;
}
if ((dc->nVerifyClient == SSL_CVERIFY_OPTIONAL) ||
(dc->nVerifyClient == SSL_CVERIFY_OPTIONAL_NO_CA) ||
(sc->server->auth.verify_mode == SSL_CVERIFY_OPTIONAL) ||
(sc->server->auth.verify_mode == SSL_CVERIFY_OPTIONAL_NO_CA))
{
verify |= SSL_VERIFY_PEER;
}
/* TODO: this seems premature since we do not know if there
* are any changes required.
*/
SSL_set_verify(ssl, verify, ssl_callback_SSLVerify);
SSL_set_verify_result(ssl, X509_V_OK);
/* determine whether we've to force a renegotiation */
if (!renegotiate && verify != verify_old) {
if (((verify_old == SSL_VERIFY_NONE) &&
(verify != SSL_VERIFY_NONE)) ||
(!(verify_old & SSL_VERIFY_PEER) &&
(verify & SSL_VERIFY_PEER)) ||
(!(verify_old & SSL_VERIFY_FAIL_IF_NO_PEER_CERT) &&
(verify & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)))
{
renegotiate = TRUE;
if (r->connection->master) {
/* The request causes renegotiation on a slave connection.
* This is not allowed since we might have concurrent requests
* on this connection.
*/
apr_table_setn(r->notes, "ssl-renegotiate-forbidden", "verify-client");
SSL_set_verify(ssl, verify_old, ssl_callback_SSLVerify);
return HTTP_FORBIDDEN;
}
/* optimization */
if ((dc->nOptions & SSL_OPT_OPTRENEGOTIATE) &&
(verify_old == SSL_VERIFY_NONE) &&
((peercert = SSL_get_peer_certificate(ssl)) != NULL))
{
renegotiate_quick = TRUE;
X509_free(peercert);
}
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02255)
"Changed client verification type will force "
"%srenegotiation",
renegotiate_quick ? "quick " : "");
}
else if (verify != SSL_VERIFY_NONE) {
/*
* override of SSLVerifyDepth
*
* The depth checks are handled by us manually inside the
* verify callback function and not by OpenSSL internally
* (and our function is aware of both the per-server and
* per-directory contexts). So we cannot ask OpenSSL about
* the currently verify depth. Instead we remember it in our
* SSLConnRec attached to the SSL* of OpenSSL. We've to force
* the renegotiation if the reconfigured/new verify depth is
* less than the currently active/remembered verify depth
* (because this means more restriction on the certificate
* chain).
*/
n = (sslconn->verify_depth != UNSET)
? sslconn->verify_depth
: hssc->server->auth.verify_depth;
/* determine the new depth */
sslconn->verify_depth = (dc->nVerifyDepth != UNSET)
? dc->nVerifyDepth
: sc->server->auth.verify_depth;
if (sslconn->verify_depth < n) {
renegotiate = TRUE;
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02254)
"Reduced client verification depth will "
"force renegotiation");
}
}
}
/* If we're handling a request for a vhost other than the default one,
* then we need to make sure that client authentication is properly
* enforced. For clients supplying an SNI extension, the peer
* certificate verification has happened in the handshake already
* (and r->server == handshakeserver). For non-SNI requests,
* an additional check is needed here. If client authentication
* is configured as mandatory, then we can only proceed if the
* CA list doesn't have to be changed (OpenSSL doesn't provide
* an option to change the list for an existing session).
*/
if ((r->server != handshakeserver)
&& renegotiate
&& ((verify & SSL_VERIFY_PEER) ||
(verify & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))) {
#define MODSSL_CFG_CA_NE(f, sc1, sc2) \
(sc1->server->auth.f && \
(!sc2->server->auth.f || \
strNE(sc1->server->auth.f, sc2->server->auth.f)))
if (MODSSL_CFG_CA_NE(ca_cert_file, sc, hssc) ||
MODSSL_CFG_CA_NE(ca_cert_path, sc, hssc)) {
if (verify & SSL_VERIFY_FAIL_IF_NO_PEER_CERT) {
ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(02256)
"Non-default virtual host with SSLVerify set to "
"'require' and VirtualHost-specific CA certificate "
"list is only available to clients with TLS server "
"name indication (SNI) support");
SSL_set_verify(ssl, verify_old, NULL);
return HTTP_FORBIDDEN;
} else
/* let it pass, possibly with an "incorrect" peer cert,
* so make sure the SSL_CLIENT_VERIFY environment variable
* will indicate partial success only, later on.
*/
sslconn->verify_info = "GENEROUS";
}
}
}
/* Fill reneg buffer if required. */
if (renegotiate && !renegotiate_quick) {
rc = fill_reneg_buffer(r, dc);
if (rc) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02257)
"could not buffer message body to allow "
"SSL renegotiation to proceed");
return rc;
}
}
/*
* now do the renegotiation if anything was actually reconfigured
*/
if (renegotiate) {
/*
* Now we force the SSL renegotiation by sending the Hello Request
* message to the client. Here we have to do a workaround: Actually
* OpenSSL returns immediately after sending the Hello Request (the
* intent AFAIK is because the SSL/TLS protocol says it's not a must
* that the client replies to a Hello Request). But because we insist
* on a reply (anything else is an error for us) we have to go to the
* ACCEPT state manually. Using SSL_set_accept_state() doesn't work
* here because it resets too much of the connection. So we set the
* state explicitly and continue the handshake manually.
*/
ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(02221)
"Requesting connection re-negotiation");
if (renegotiate_quick) {
STACK_OF(X509) *cert_stack;
X509 *cert;
/* perform just a manual re-verification of the peer */
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02258)
"Performing quick renegotiation: "
"just re-verifying the peer");
cert_stack = (STACK_OF(X509) *)SSL_get_peer_cert_chain(ssl);
cert = SSL_get_peer_certificate(ssl);
if (!cert_stack || (sk_X509_num(cert_stack) == 0)) {
if (!cert) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02222)
"Cannot find peer certificate chain");
return HTTP_FORBIDDEN;
}
/* client cert is in the session cache, but there is
* no chain, since ssl3_get_client_certificate()
* sk_X509_shift-ed the peer cert out of the chain.
* we put it back here for the purpose of quick_renegotiation.
*/
cert_stack = sk_X509_new_null();
sk_X509_push(cert_stack, cert);
}
if (!(cert_store ||
(cert_store = SSL_CTX_get_cert_store(ctx))))
{
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02223)
"Cannot find certificate storage");
return HTTP_FORBIDDEN;
}
if (!cert) {
cert = sk_X509_value(cert_stack, 0);
}
cert_store_ctx = X509_STORE_CTX_new();
if (!X509_STORE_CTX_init(cert_store_ctx, cert_store, cert, cert_stack)) {
X509_STORE_CTX_free(cert_store_ctx);
return HTTP_FORBIDDEN;
}
depth = SSL_get_verify_depth(ssl);
if (depth >= 0) {
X509_STORE_CTX_set_depth(cert_store_ctx, depth);
}
X509_STORE_CTX_set_ex_data(cert_store_ctx,
SSL_get_ex_data_X509_STORE_CTX_idx(),
(char *)ssl);
if (!X509_verify_cert(cert_store_ctx)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02224)
"Re-negotiation verification step failed");
ssl_log_ssl_error(SSLLOG_MARK, APLOG_ERR, r->server);
}
SSL_set_verify_result(ssl, X509_STORE_CTX_get_error(cert_store_ctx));
X509_STORE_CTX_cleanup(cert_store_ctx);
X509_STORE_CTX_free(cert_store_ctx);
if (cert_stack != SSL_get_peer_cert_chain(ssl)) {
/* we created this ourselves, so free it */
sk_X509_pop_free(cert_stack, X509_free);
}
}
else {
char peekbuf[1];
const char *reneg_support;
request_rec *id = r->main ? r->main : r;
/* Additional mitigation for CVE-2009-3555: At this point,
* before renegotiating, an (entire) request has been read
* from the connection. An attacker may have sent further
* data to "prefix" any subsequent request by the victim's
* client after the renegotiation; this data may already
* have been read and buffered. Forcing a connection
* closure after the response ensures such data will be
* discarded. Legimately pipelined HTTP requests will be
* retried anyway with this approach. */
if (has_buffered_data(r)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02259)
"insecure SSL re-negotiation required, but "
"a pipelined request is present; keepalive "
"disabled");
r->connection->keepalive = AP_CONN_CLOSE;
}
#if defined(SSL_get_secure_renegotiation_support)
reneg_support = SSL_get_secure_renegotiation_support(ssl) ?
"client does" : "client does not";
#else
reneg_support = "server does not";
#endif
/* Perform a full renegotiation. */
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02260)
"Performing full renegotiation: complete handshake "
"protocol (%s support secure renegotiation)",
reneg_support);
if(!SSL_set_session_id_context(ssl,
(unsigned char *)&id,
sizeof(id))) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10422)
"error setting SSL session context");
ssl_log_ssl_error(SSLLOG_MARK, APLOG_ERR, r->server);
r->connection->keepalive = AP_CONN_CLOSE;
return HTTP_FORBIDDEN;
}
/* Toggle the renegotiation state to allow the new
* handshake to proceed. */
modssl_set_reneg_state(sslconn, RENEG_ALLOW);
if(!SSL_renegotiate(ssl) || (SSL_do_handshake(ssl) != 1) || !SSL_is_init_finished(ssl)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02225)
"Re-negotiation request failed");
ssl_log_ssl_error(SSLLOG_MARK, APLOG_ERR, r->server);
r->connection->keepalive = AP_CONN_CLOSE;
return HTTP_FORBIDDEN;
}
ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(02226)
"Awaiting re-negotiation handshake");
/* XXX: Should replace setting state with SSL_renegotiate(ssl);
* However, this causes failures in perl-framework currently,
* perhaps pre-test if we have already negotiated?
*/
/* Need to trigger renegotiation handshake by reading.
* Peeking 0 bytes actually works.
* See: http://marc.info/?t=145493359200002&r=1&w=2
*/
SSL_peek(ssl, peekbuf, 0);
modssl_set_reneg_state(sslconn, RENEG_REJECT);
if (!SSL_is_init_finished(ssl)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02261)
"Re-negotiation handshake failed");
ssl_log_ssl_error(SSLLOG_MARK, APLOG_ERR, r->server);
r->connection->keepalive = AP_CONN_CLOSE;
return HTTP_FORBIDDEN;
}
/* Full renegotiation successful, we now have handshaken with
* this server's parameters.
*/
sslconn->server = r->server;
}
/*
* Finally check for acceptable renegotiation results
*/
if (OK != (rc = ssl_check_post_client_verify(r, sc, dc, sslconn, ssl))) {
return rc;
}
/*
* Also check that SSLCipherSuite has been enforced as expected.
*/
if (cipher_list) {
cipher = SSL_get_current_cipher(ssl);
if (sk_SSL_CIPHER_find(cipher_list, cipher) < 0) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02264)
"SSL cipher suite not renegotiated: "
"access to %s denied using cipher %s",
r->filename,
SSL_CIPHER_get_name(cipher));
return HTTP_FORBIDDEN;
}
}
/* remember any new cipher suite used in renegotiation */
if (ncipher_suite) {
sslconn->cipher_suite = ncipher_suite;
}
}
return DECLINED;
}
#if SSL_HAVE_PROTOCOL_TLSV1_3
/*
* Access Handler, modern flavour, for SSL/TLS v1.3 and onward.
* Only client certificates can be requested, everything else stays.
*/
static int ssl_hook_Access_modern(request_rec *r, SSLSrvConfigRec *sc, SSLDirConfigRec *dc,
SSLConnRec *sslconn, SSL *ssl)
{
if ((dc->nVerifyClient != SSL_CVERIFY_UNSET) ||
(sc->server->auth.verify_mode != SSL_CVERIFY_UNSET)) {
int vmode_inplace, vmode_needed;
int change_vmode = FALSE;
int n, rc;
vmode_inplace = SSL_get_verify_mode(ssl);
vmode_needed = SSL_VERIFY_NONE;
if ((dc->nVerifyClient == SSL_CVERIFY_REQUIRE) ||
(sc->server->auth.verify_mode == SSL_CVERIFY_REQUIRE)) {
vmode_needed |= SSL_VERIFY_PEER_STRICT;
}
if ((dc->nVerifyClient == SSL_CVERIFY_OPTIONAL) ||
(dc->nVerifyClient == SSL_CVERIFY_OPTIONAL_NO_CA) ||
(sc->server->auth.verify_mode == SSL_CVERIFY_OPTIONAL) ||
(sc->server->auth.verify_mode == SSL_CVERIFY_OPTIONAL_NO_CA))
{
vmode_needed |= SSL_VERIFY_PEER;
}
if (vmode_needed == SSL_VERIFY_NONE) {
return DECLINED;
}
if (vmode_inplace != vmode_needed) {
/* Need to change, if new setting is more restrictive than existing one */
if ((vmode_inplace == SSL_VERIFY_NONE)
|| (!(vmode_inplace & SSL_VERIFY_PEER)
&& (vmode_needed & SSL_VERIFY_PEER))
|| (!(vmode_inplace & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)
&& (vmode_needed & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))) {
/* need to change the effective verify mode */
change_vmode = TRUE;
}
else {
/* FIXME: does this work with TLSv1.3? Is this more than re-inspecting
* the certificate we should already have? */
/*
* override of SSLVerifyDepth
*
* The depth checks are handled by us manually inside the
* verify callback function and not by OpenSSL internally
* (and our function is aware of both the per-server and
* per-directory contexts). So we cannot ask OpenSSL about
* the currently verify depth. Instead we remember it in our
* SSLConnRec attached to the SSL* of OpenSSL. We've to force
* the renegotiation if the reconfigured/new verify depth is
* less than the currently active/remembered verify depth
* (because this means more restriction on the certificate
* chain).
*/
n = (sslconn->verify_depth != UNSET)?
sslconn->verify_depth : sc->server->auth.verify_depth;
/* determine the new depth */
sslconn->verify_depth = (dc->nVerifyDepth != UNSET)
? dc->nVerifyDepth
: sc->server->auth.verify_depth;
if (sslconn->verify_depth < n) {
change_vmode = TRUE;
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(10128)
"Reduced client verification depth will "
"force renegotiation");
}
}
}
/* Fill reneg buffer if required. */
if (change_vmode) {
char peekbuf[1];
if (r->connection->master) {
/* FIXME: modifying the SSL on a slave connection is no good.
* We would need to push this back to the master connection