1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2 * All rights reserved.
3 *
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
7 *
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
14 *
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
21 *
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
24 * are met:
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50 * SUCH DAMAGE.
51 *
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
56 */
57 /* ====================================================================
58 * Copyright (c) 1998-2007 The OpenSSL Project. All rights reserved.
59 *
60 * Redistribution and use in source and binary forms, with or without
61 * modification, are permitted provided that the following conditions
62 * are met:
63 *
64 * 1. Redistributions of source code must retain the above copyright
65 * notice, this list of conditions and the following disclaimer.
66 *
67 * 2. Redistributions in binary form must reproduce the above copyright
68 * notice, this list of conditions and the following disclaimer in
69 * the documentation and/or other materials provided with the
70 * distribution.
71 *
72 * 3. All advertising materials mentioning features or use of this
73 * software must display the following acknowledgment:
74 * "This product includes software developed by the OpenSSL Project
75 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
76 *
77 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
78 * endorse or promote products derived from this software without
79 * prior written permission. For written permission, please contact
80 * openssl-core@openssl.org.
81 *
82 * 5. Products derived from this software may not be called "OpenSSL"
83 * nor may "OpenSSL" appear in their names without prior written
84 * permission of the OpenSSL Project.
85 *
86 * 6. Redistributions of any form whatsoever must retain the following
87 * acknowledgment:
88 * "This product includes software developed by the OpenSSL Project
89 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
90 *
91 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
92 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
93 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
94 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
95 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
96 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
97 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
98 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
99 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
100 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
101 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
102 * OF THE POSSIBILITY OF SUCH DAMAGE.
103 * ====================================================================
104 *
105 * This product includes cryptographic software written by Eric Young
106 * (eay@cryptsoft.com). This product includes software written by Tim
107 * Hudson (tjh@cryptsoft.com).
108 *
109 */
110 /* ====================================================================
111 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
112 * ECC cipher suite support in OpenSSL originally developed by
113 * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project. */
114
115 #include <openssl/ssl.h>
116
117 #include <assert.h>
118 #include <limits.h>
119 #include <string.h>
120
121 #include <openssl/bn.h>
122 #include <openssl/buf.h>
123 #include <openssl/bytestring.h>
124 #include <openssl/ec_key.h>
125 #include <openssl/err.h>
126 #include <openssl/mem.h>
127 #include <openssl/sha.h>
128 #include <openssl/x509.h>
129
130 #include "../crypto/internal.h"
131 #include "internal.h"
132
133
ssl_cert_new(const SSL_X509_METHOD * x509_method)134 CERT *ssl_cert_new(const SSL_X509_METHOD *x509_method) {
135 CERT *ret = (CERT *)OPENSSL_malloc(sizeof(CERT));
136 if (ret == NULL) {
137 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
138 return NULL;
139 }
140 OPENSSL_memset(ret, 0, sizeof(CERT));
141 ret->x509_method = x509_method;
142
143 return ret;
144 }
145
buffer_up_ref(CRYPTO_BUFFER * buffer)146 static CRYPTO_BUFFER *buffer_up_ref(CRYPTO_BUFFER *buffer) {
147 CRYPTO_BUFFER_up_ref(buffer);
148 return buffer;
149 }
150
ssl_cert_dup(CERT * cert)151 CERT *ssl_cert_dup(CERT *cert) {
152 CERT *ret = (CERT *)OPENSSL_malloc(sizeof(CERT));
153 if (ret == NULL) {
154 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
155 return NULL;
156 }
157 OPENSSL_memset(ret, 0, sizeof(CERT));
158
159 ret->chain = sk_CRYPTO_BUFFER_deep_copy(cert->chain, buffer_up_ref,
160 CRYPTO_BUFFER_free);
161
162 if (cert->privatekey != NULL) {
163 EVP_PKEY_up_ref(cert->privatekey);
164 ret->privatekey = cert->privatekey;
165 }
166
167 ret->key_method = cert->key_method;
168 ret->x509_method = cert->x509_method;
169
170 if (cert->sigalgs != NULL) {
171 ret->sigalgs = (uint16_t *)BUF_memdup(
172 cert->sigalgs, cert->num_sigalgs * sizeof(cert->sigalgs[0]));
173 if (ret->sigalgs == NULL) {
174 goto err;
175 }
176 }
177 ret->num_sigalgs = cert->num_sigalgs;
178
179 ret->cert_cb = cert->cert_cb;
180 ret->cert_cb_arg = cert->cert_cb_arg;
181
182 ret->x509_method->cert_dup(ret, cert);
183
184 if (cert->signed_cert_timestamp_list != NULL) {
185 CRYPTO_BUFFER_up_ref(cert->signed_cert_timestamp_list);
186 ret->signed_cert_timestamp_list = cert->signed_cert_timestamp_list;
187 }
188
189 if (cert->ocsp_response != NULL) {
190 CRYPTO_BUFFER_up_ref(cert->ocsp_response);
191 ret->ocsp_response = cert->ocsp_response;
192 }
193
194 ret->sid_ctx_length = cert->sid_ctx_length;
195 OPENSSL_memcpy(ret->sid_ctx, cert->sid_ctx, sizeof(ret->sid_ctx));
196
197 ret->enable_early_data = cert->enable_early_data;
198
199 return ret;
200
201 err:
202 ssl_cert_free(ret);
203 return NULL;
204 }
205
206 /* Free up and clear all certificates and chains */
ssl_cert_clear_certs(CERT * cert)207 void ssl_cert_clear_certs(CERT *cert) {
208 if (cert == NULL) {
209 return;
210 }
211
212 cert->x509_method->cert_clear(cert);
213
214 sk_CRYPTO_BUFFER_pop_free(cert->chain, CRYPTO_BUFFER_free);
215 cert->chain = NULL;
216 EVP_PKEY_free(cert->privatekey);
217 cert->privatekey = NULL;
218 cert->key_method = NULL;
219 }
220
ssl_cert_free(CERT * c)221 void ssl_cert_free(CERT *c) {
222 if (c == NULL) {
223 return;
224 }
225
226 ssl_cert_clear_certs(c);
227 c->x509_method->cert_free(c);
228 OPENSSL_free(c->sigalgs);
229 CRYPTO_BUFFER_free(c->signed_cert_timestamp_list);
230 CRYPTO_BUFFER_free(c->ocsp_response);
231
232 OPENSSL_free(c);
233 }
234
ssl_cert_set_cert_cb(CERT * c,int (* cb)(SSL * ssl,void * arg),void * arg)235 static void ssl_cert_set_cert_cb(CERT *c, int (*cb)(SSL *ssl, void *arg),
236 void *arg) {
237 c->cert_cb = cb;
238 c->cert_cb_arg = arg;
239 }
240
241 enum leaf_cert_and_privkey_result_t {
242 leaf_cert_and_privkey_error,
243 leaf_cert_and_privkey_ok,
244 leaf_cert_and_privkey_mismatch,
245 };
246
247 /* check_leaf_cert_and_privkey checks whether the certificate in |leaf_buffer|
248 * and the private key in |privkey| are suitable and coherent. It returns
249 * |leaf_cert_and_privkey_error| and pushes to the error queue if a problem is
250 * found. If the certificate and private key are valid, but incoherent, it
251 * returns |leaf_cert_and_privkey_mismatch|. Otherwise it returns
252 * |leaf_cert_and_privkey_ok|. */
check_leaf_cert_and_privkey(CRYPTO_BUFFER * leaf_buffer,EVP_PKEY * privkey)253 static enum leaf_cert_and_privkey_result_t check_leaf_cert_and_privkey(
254 CRYPTO_BUFFER *leaf_buffer, EVP_PKEY *privkey) {
255 enum leaf_cert_and_privkey_result_t ret = leaf_cert_and_privkey_error;
256
257 CBS cert_cbs;
258 CRYPTO_BUFFER_init_CBS(leaf_buffer, &cert_cbs);
259 EVP_PKEY *pubkey = ssl_cert_parse_pubkey(&cert_cbs);
260 if (pubkey == NULL) {
261 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
262 goto out;
263 }
264
265 if (!ssl_is_key_type_supported(pubkey->type)) {
266 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
267 goto out;
268 }
269
270 /* An ECC certificate may be usable for ECDH or ECDSA. We only support ECDSA
271 * certificates, so sanity-check the key usage extension. */
272 if (pubkey->type == EVP_PKEY_EC &&
273 !ssl_cert_check_digital_signature_key_usage(&cert_cbs)) {
274 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
275 goto out;
276 }
277
278 if (privkey != NULL &&
279 /* Sanity-check that the private key and the certificate match. */
280 !ssl_compare_public_and_private_key(pubkey, privkey)) {
281 ERR_clear_error();
282 ret = leaf_cert_and_privkey_mismatch;
283 goto out;
284 }
285
286 ret = leaf_cert_and_privkey_ok;
287
288 out:
289 EVP_PKEY_free(pubkey);
290 return ret;
291 }
292
cert_set_chain_and_key(CERT * cert,CRYPTO_BUFFER * const * certs,size_t num_certs,EVP_PKEY * privkey,const SSL_PRIVATE_KEY_METHOD * privkey_method)293 static int cert_set_chain_and_key(
294 CERT *cert, CRYPTO_BUFFER *const *certs, size_t num_certs,
295 EVP_PKEY *privkey, const SSL_PRIVATE_KEY_METHOD *privkey_method) {
296 if (num_certs == 0 ||
297 (privkey == NULL && privkey_method == NULL)) {
298 OPENSSL_PUT_ERROR(SSL, ERR_R_PASSED_NULL_PARAMETER);
299 return 0;
300 }
301
302 if (privkey != NULL && privkey_method != NULL) {
303 OPENSSL_PUT_ERROR(SSL, SSL_R_CANNOT_HAVE_BOTH_PRIVKEY_AND_METHOD);
304 return 0;
305 }
306
307 switch (check_leaf_cert_and_privkey(certs[0], privkey)) {
308 case leaf_cert_and_privkey_error:
309 return 0;
310 case leaf_cert_and_privkey_mismatch:
311 OPENSSL_PUT_ERROR(SSL, SSL_R_CERTIFICATE_AND_PRIVATE_KEY_MISMATCH);
312 return 0;
313 case leaf_cert_and_privkey_ok:
314 break;
315 }
316
317 STACK_OF(CRYPTO_BUFFER) *certs_sk = sk_CRYPTO_BUFFER_new_null();
318 if (certs_sk == NULL) {
319 return 0;
320 }
321
322 for (size_t i = 0; i < num_certs; i++) {
323 if (!sk_CRYPTO_BUFFER_push(certs_sk, certs[i])) {
324 sk_CRYPTO_BUFFER_pop_free(certs_sk, CRYPTO_BUFFER_free);
325 return 0;
326 }
327 CRYPTO_BUFFER_up_ref(certs[i]);
328 }
329
330 EVP_PKEY_free(cert->privatekey);
331 cert->privatekey = privkey;
332 if (privkey != NULL) {
333 EVP_PKEY_up_ref(privkey);
334 }
335 cert->key_method = privkey_method;
336
337 sk_CRYPTO_BUFFER_pop_free(cert->chain, CRYPTO_BUFFER_free);
338 cert->chain = certs_sk;
339
340 return 1;
341 }
342
SSL_set_chain_and_key(SSL * ssl,CRYPTO_BUFFER * const * certs,size_t num_certs,EVP_PKEY * privkey,const SSL_PRIVATE_KEY_METHOD * privkey_method)343 int SSL_set_chain_and_key(SSL *ssl, CRYPTO_BUFFER *const *certs,
344 size_t num_certs, EVP_PKEY *privkey,
345 const SSL_PRIVATE_KEY_METHOD *privkey_method) {
346 return cert_set_chain_and_key(ssl->cert, certs, num_certs, privkey,
347 privkey_method);
348 }
349
SSL_CTX_set_chain_and_key(SSL_CTX * ctx,CRYPTO_BUFFER * const * certs,size_t num_certs,EVP_PKEY * privkey,const SSL_PRIVATE_KEY_METHOD * privkey_method)350 int SSL_CTX_set_chain_and_key(SSL_CTX *ctx, CRYPTO_BUFFER *const *certs,
351 size_t num_certs, EVP_PKEY *privkey,
352 const SSL_PRIVATE_KEY_METHOD *privkey_method) {
353 return cert_set_chain_and_key(ctx->cert, certs, num_certs, privkey,
354 privkey_method);
355 }
356
ssl_set_cert(CERT * cert,CRYPTO_BUFFER * buffer)357 int ssl_set_cert(CERT *cert, CRYPTO_BUFFER *buffer) {
358 switch (check_leaf_cert_and_privkey(buffer, cert->privatekey)) {
359 case leaf_cert_and_privkey_error:
360 return 0;
361 case leaf_cert_and_privkey_mismatch:
362 /* don't fail for a cert/key mismatch, just free current private key
363 * (when switching to a different cert & key, first this function should
364 * be used, then |ssl_set_pkey|. */
365 EVP_PKEY_free(cert->privatekey);
366 cert->privatekey = NULL;
367 break;
368 case leaf_cert_and_privkey_ok:
369 break;
370 }
371
372 cert->x509_method->cert_flush_cached_leaf(cert);
373
374 if (cert->chain != NULL) {
375 CRYPTO_BUFFER_free(sk_CRYPTO_BUFFER_value(cert->chain, 0));
376 sk_CRYPTO_BUFFER_set(cert->chain, 0, buffer);
377 CRYPTO_BUFFER_up_ref(buffer);
378 return 1;
379 }
380
381 cert->chain = sk_CRYPTO_BUFFER_new_null();
382 if (cert->chain == NULL) {
383 return 0;
384 }
385
386 if (!sk_CRYPTO_BUFFER_push(cert->chain, buffer)) {
387 sk_CRYPTO_BUFFER_free(cert->chain);
388 cert->chain = NULL;
389 return 0;
390 }
391 CRYPTO_BUFFER_up_ref(buffer);
392
393 return 1;
394 }
395
SSL_CTX_use_certificate_ASN1(SSL_CTX * ctx,size_t der_len,const uint8_t * der)396 int SSL_CTX_use_certificate_ASN1(SSL_CTX *ctx, size_t der_len,
397 const uint8_t *der) {
398 CRYPTO_BUFFER *buffer = CRYPTO_BUFFER_new(der, der_len, NULL);
399 if (buffer == NULL) {
400 return 0;
401 }
402
403 const int ok = ssl_set_cert(ctx->cert, buffer);
404 CRYPTO_BUFFER_free(buffer);
405 return ok;
406 }
407
SSL_use_certificate_ASN1(SSL * ssl,const uint8_t * der,size_t der_len)408 int SSL_use_certificate_ASN1(SSL *ssl, const uint8_t *der, size_t der_len) {
409 CRYPTO_BUFFER *buffer = CRYPTO_BUFFER_new(der, der_len, NULL);
410 if (buffer == NULL) {
411 return 0;
412 }
413
414 const int ok = ssl_set_cert(ssl->cert, buffer);
415 CRYPTO_BUFFER_free(buffer);
416 return ok;
417 }
418
ssl_has_certificate(const SSL * ssl)419 int ssl_has_certificate(const SSL *ssl) {
420 return ssl->cert->chain != NULL &&
421 sk_CRYPTO_BUFFER_value(ssl->cert->chain, 0) != NULL &&
422 ssl_has_private_key(ssl);
423 }
424
STACK_OF(CRYPTO_BUFFER)425 STACK_OF(CRYPTO_BUFFER) *ssl_parse_cert_chain(uint8_t *out_alert,
426 EVP_PKEY **out_pubkey,
427 uint8_t *out_leaf_sha256,
428 CBS *cbs,
429 CRYPTO_BUFFER_POOL *pool) {
430 *out_pubkey = NULL;
431
432 STACK_OF(CRYPTO_BUFFER) *ret = sk_CRYPTO_BUFFER_new_null();
433 if (ret == NULL) {
434 *out_alert = SSL_AD_INTERNAL_ERROR;
435 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
436 return NULL;
437 }
438
439 CBS certificate_list;
440 if (!CBS_get_u24_length_prefixed(cbs, &certificate_list)) {
441 *out_alert = SSL_AD_DECODE_ERROR;
442 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
443 goto err;
444 }
445
446 while (CBS_len(&certificate_list) > 0) {
447 CBS certificate;
448 if (!CBS_get_u24_length_prefixed(&certificate_list, &certificate) ||
449 CBS_len(&certificate) == 0) {
450 *out_alert = SSL_AD_DECODE_ERROR;
451 OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_LENGTH_MISMATCH);
452 goto err;
453 }
454
455 if (sk_CRYPTO_BUFFER_num(ret) == 0) {
456 *out_pubkey = ssl_cert_parse_pubkey(&certificate);
457 if (*out_pubkey == NULL) {
458 *out_alert = SSL_AD_DECODE_ERROR;
459 goto err;
460 }
461
462 /* Retain the hash of the leaf certificate if requested. */
463 if (out_leaf_sha256 != NULL) {
464 SHA256(CBS_data(&certificate), CBS_len(&certificate), out_leaf_sha256);
465 }
466 }
467
468 CRYPTO_BUFFER *buf =
469 CRYPTO_BUFFER_new_from_CBS(&certificate, pool);
470 if (buf == NULL) {
471 *out_alert = SSL_AD_DECODE_ERROR;
472 goto err;
473 }
474
475 if (!sk_CRYPTO_BUFFER_push(ret, buf)) {
476 *out_alert = SSL_AD_INTERNAL_ERROR;
477 CRYPTO_BUFFER_free(buf);
478 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
479 goto err;
480 }
481 }
482
483 return ret;
484
485 err:
486 EVP_PKEY_free(*out_pubkey);
487 *out_pubkey = NULL;
488 sk_CRYPTO_BUFFER_pop_free(ret, CRYPTO_BUFFER_free);
489 return NULL;
490 }
491
ssl_add_cert_chain(SSL * ssl,CBB * cbb)492 int ssl_add_cert_chain(SSL *ssl, CBB *cbb) {
493 if (!ssl_has_certificate(ssl)) {
494 return CBB_add_u24(cbb, 0);
495 }
496
497 CBB certs;
498 if (!CBB_add_u24_length_prefixed(cbb, &certs)) {
499 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
500 return 0;
501 }
502
503 STACK_OF(CRYPTO_BUFFER) *chain = ssl->cert->chain;
504 for (size_t i = 0; i < sk_CRYPTO_BUFFER_num(chain); i++) {
505 CRYPTO_BUFFER *buffer = sk_CRYPTO_BUFFER_value(chain, i);
506 CBB child;
507 if (!CBB_add_u24_length_prefixed(&certs, &child) ||
508 !CBB_add_bytes(&child, CRYPTO_BUFFER_data(buffer),
509 CRYPTO_BUFFER_len(buffer)) ||
510 !CBB_flush(&certs)) {
511 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
512 return 0;
513 }
514 }
515
516 return CBB_flush(cbb);
517 }
518
519 /* ssl_cert_skip_to_spki parses a DER-encoded, X.509 certificate from |in| and
520 * positions |*out_tbs_cert| to cover the TBSCertificate, starting at the
521 * subjectPublicKeyInfo. */
ssl_cert_skip_to_spki(const CBS * in,CBS * out_tbs_cert)522 static int ssl_cert_skip_to_spki(const CBS *in, CBS *out_tbs_cert) {
523 /* From RFC 5280, section 4.1
524 * Certificate ::= SEQUENCE {
525 * tbsCertificate TBSCertificate,
526 * signatureAlgorithm AlgorithmIdentifier,
527 * signatureValue BIT STRING }
528
529 * TBSCertificate ::= SEQUENCE {
530 * version [0] EXPLICIT Version DEFAULT v1,
531 * serialNumber CertificateSerialNumber,
532 * signature AlgorithmIdentifier,
533 * issuer Name,
534 * validity Validity,
535 * subject Name,
536 * subjectPublicKeyInfo SubjectPublicKeyInfo,
537 * ... } */
538 CBS buf = *in;
539
540 CBS toplevel;
541 if (!CBS_get_asn1(&buf, &toplevel, CBS_ASN1_SEQUENCE) ||
542 CBS_len(&buf) != 0 ||
543 !CBS_get_asn1(&toplevel, out_tbs_cert, CBS_ASN1_SEQUENCE) ||
544 /* version */
545 !CBS_get_optional_asn1(
546 out_tbs_cert, NULL, NULL,
547 CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 0) ||
548 /* serialNumber */
549 !CBS_get_asn1(out_tbs_cert, NULL, CBS_ASN1_INTEGER) ||
550 /* signature algorithm */
551 !CBS_get_asn1(out_tbs_cert, NULL, CBS_ASN1_SEQUENCE) ||
552 /* issuer */
553 !CBS_get_asn1(out_tbs_cert, NULL, CBS_ASN1_SEQUENCE) ||
554 /* validity */
555 !CBS_get_asn1(out_tbs_cert, NULL, CBS_ASN1_SEQUENCE) ||
556 /* subject */
557 !CBS_get_asn1(out_tbs_cert, NULL, CBS_ASN1_SEQUENCE)) {
558 return 0;
559 }
560
561 return 1;
562 }
563
ssl_cert_parse_pubkey(const CBS * in)564 EVP_PKEY *ssl_cert_parse_pubkey(const CBS *in) {
565 CBS buf = *in, tbs_cert;
566 if (!ssl_cert_skip_to_spki(&buf, &tbs_cert)) {
567 OPENSSL_PUT_ERROR(SSL, SSL_R_CANNOT_PARSE_LEAF_CERT);
568 return NULL;
569 }
570
571 return EVP_parse_public_key(&tbs_cert);
572 }
573
ssl_compare_public_and_private_key(const EVP_PKEY * pubkey,const EVP_PKEY * privkey)574 int ssl_compare_public_and_private_key(const EVP_PKEY *pubkey,
575 const EVP_PKEY *privkey) {
576 if (EVP_PKEY_is_opaque(privkey)) {
577 /* We cannot check an opaque private key and have to trust that it
578 * matches. */
579 return 1;
580 }
581
582 int ret = 0;
583
584 switch (EVP_PKEY_cmp(pubkey, privkey)) {
585 case 1:
586 ret = 1;
587 break;
588 case 0:
589 OPENSSL_PUT_ERROR(X509, X509_R_KEY_VALUES_MISMATCH);
590 break;
591 case -1:
592 OPENSSL_PUT_ERROR(X509, X509_R_KEY_TYPE_MISMATCH);
593 break;
594 case -2:
595 OPENSSL_PUT_ERROR(X509, X509_R_UNKNOWN_KEY_TYPE);
596 default:
597 assert(0);
598 break;
599 }
600
601 return ret;
602 }
603
ssl_cert_check_private_key(const CERT * cert,const EVP_PKEY * privkey)604 int ssl_cert_check_private_key(const CERT *cert, const EVP_PKEY *privkey) {
605 if (privkey == NULL) {
606 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_PRIVATE_KEY_ASSIGNED);
607 return 0;
608 }
609
610 if (cert->chain == NULL ||
611 sk_CRYPTO_BUFFER_value(cert->chain, 0) == NULL) {
612 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CERTIFICATE_ASSIGNED);
613 return 0;
614 }
615
616 CBS cert_cbs;
617 CRYPTO_BUFFER_init_CBS(sk_CRYPTO_BUFFER_value(cert->chain, 0), &cert_cbs);
618 EVP_PKEY *pubkey = ssl_cert_parse_pubkey(&cert_cbs);
619 if (!pubkey) {
620 OPENSSL_PUT_ERROR(X509, X509_R_UNKNOWN_KEY_TYPE);
621 return 0;
622 }
623
624 const int ok = ssl_compare_public_and_private_key(pubkey, privkey);
625 EVP_PKEY_free(pubkey);
626 return ok;
627 }
628
ssl_cert_check_digital_signature_key_usage(const CBS * in)629 int ssl_cert_check_digital_signature_key_usage(const CBS *in) {
630 CBS buf = *in;
631
632 CBS tbs_cert, outer_extensions;
633 int has_extensions;
634 if (!ssl_cert_skip_to_spki(&buf, &tbs_cert) ||
635 /* subjectPublicKeyInfo */
636 !CBS_get_asn1(&tbs_cert, NULL, CBS_ASN1_SEQUENCE) ||
637 /* issuerUniqueID */
638 !CBS_get_optional_asn1(
639 &tbs_cert, NULL, NULL,
640 CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 1) ||
641 /* subjectUniqueID */
642 !CBS_get_optional_asn1(
643 &tbs_cert, NULL, NULL,
644 CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 2) ||
645 !CBS_get_optional_asn1(
646 &tbs_cert, &outer_extensions, &has_extensions,
647 CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 3)) {
648 goto parse_err;
649 }
650
651 if (!has_extensions) {
652 return 1;
653 }
654
655 CBS extensions;
656 if (!CBS_get_asn1(&outer_extensions, &extensions, CBS_ASN1_SEQUENCE)) {
657 goto parse_err;
658 }
659
660 while (CBS_len(&extensions) > 0) {
661 CBS extension, oid, contents;
662 if (!CBS_get_asn1(&extensions, &extension, CBS_ASN1_SEQUENCE) ||
663 !CBS_get_asn1(&extension, &oid, CBS_ASN1_OBJECT) ||
664 (CBS_peek_asn1_tag(&extension, CBS_ASN1_BOOLEAN) &&
665 !CBS_get_asn1(&extension, NULL, CBS_ASN1_BOOLEAN)) ||
666 !CBS_get_asn1(&extension, &contents, CBS_ASN1_OCTETSTRING) ||
667 CBS_len(&extension) != 0) {
668 goto parse_err;
669 }
670
671 static const uint8_t kKeyUsageOID[3] = {0x55, 0x1d, 0x0f};
672 if (CBS_len(&oid) != sizeof(kKeyUsageOID) ||
673 OPENSSL_memcmp(CBS_data(&oid), kKeyUsageOID, sizeof(kKeyUsageOID)) !=
674 0) {
675 continue;
676 }
677
678 CBS bit_string;
679 if (!CBS_get_asn1(&contents, &bit_string, CBS_ASN1_BITSTRING) ||
680 CBS_len(&contents) != 0) {
681 goto parse_err;
682 }
683
684 /* This is the KeyUsage extension. See
685 * https://tools.ietf.org/html/rfc5280#section-4.2.1.3 */
686 if (!CBS_is_valid_asn1_bitstring(&bit_string)) {
687 goto parse_err;
688 }
689
690 if (!CBS_asn1_bitstring_has_bit(&bit_string, 0)) {
691 OPENSSL_PUT_ERROR(SSL, SSL_R_ECC_CERT_NOT_FOR_SIGNING);
692 return 0;
693 }
694
695 return 1;
696 }
697
698 /* No KeyUsage extension found. */
699 return 1;
700
701 parse_err:
702 OPENSSL_PUT_ERROR(SSL, SSL_R_CANNOT_PARSE_LEAF_CERT);
703 return 0;
704 }
705
STACK_OF(CRYPTO_BUFFER)706 STACK_OF(CRYPTO_BUFFER) *
707 ssl_parse_client_CA_list(SSL *ssl, uint8_t *out_alert, CBS *cbs) {
708 CRYPTO_BUFFER_POOL *const pool = ssl->ctx->pool;
709
710 STACK_OF(CRYPTO_BUFFER) *ret = sk_CRYPTO_BUFFER_new_null();
711 if (ret == NULL) {
712 *out_alert = SSL_AD_INTERNAL_ERROR;
713 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
714 return NULL;
715 }
716
717 CBS child;
718 if (!CBS_get_u16_length_prefixed(cbs, &child)) {
719 *out_alert = SSL_AD_DECODE_ERROR;
720 OPENSSL_PUT_ERROR(SSL, SSL_R_LENGTH_MISMATCH);
721 goto err;
722 }
723
724 while (CBS_len(&child) > 0) {
725 CBS distinguished_name;
726 if (!CBS_get_u16_length_prefixed(&child, &distinguished_name)) {
727 *out_alert = SSL_AD_DECODE_ERROR;
728 OPENSSL_PUT_ERROR(SSL, SSL_R_CA_DN_TOO_LONG);
729 goto err;
730 }
731
732 CRYPTO_BUFFER *buffer =
733 CRYPTO_BUFFER_new_from_CBS(&distinguished_name, pool);
734 if (buffer == NULL ||
735 !sk_CRYPTO_BUFFER_push(ret, buffer)) {
736 CRYPTO_BUFFER_free(buffer);
737 *out_alert = SSL_AD_INTERNAL_ERROR;
738 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
739 goto err;
740 }
741 }
742
743 if (!ssl->ctx->x509_method->check_client_CA_list(ret)) {
744 *out_alert = SSL_AD_INTERNAL_ERROR;
745 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
746 goto err;
747 }
748
749 return ret;
750
751 err:
752 sk_CRYPTO_BUFFER_pop_free(ret, CRYPTO_BUFFER_free);
753 return NULL;
754 }
755
ssl_add_client_CA_list(SSL * ssl,CBB * cbb)756 int ssl_add_client_CA_list(SSL *ssl, CBB *cbb) {
757 CBB child, name_cbb;
758 if (!CBB_add_u16_length_prefixed(cbb, &child)) {
759 return 0;
760 }
761
762 STACK_OF(CRYPTO_BUFFER) *names = ssl->client_CA;
763 if (names == NULL) {
764 names = ssl->ctx->client_CA;
765 }
766 if (names == NULL) {
767 return CBB_flush(cbb);
768 }
769
770 for (size_t i = 0; i < sk_CRYPTO_BUFFER_num(names); i++) {
771 const CRYPTO_BUFFER *name = sk_CRYPTO_BUFFER_value(names, i);
772
773 if (!CBB_add_u16_length_prefixed(&child, &name_cbb) ||
774 !CBB_add_bytes(&name_cbb, CRYPTO_BUFFER_data(name),
775 CRYPTO_BUFFER_len(name))) {
776 return 0;
777 }
778 }
779
780 return CBB_flush(cbb);
781 }
782
SSL_CTX_set_cert_cb(SSL_CTX * ctx,int (* cb)(SSL * ssl,void * arg),void * arg)783 void SSL_CTX_set_cert_cb(SSL_CTX *ctx, int (*cb)(SSL *ssl, void *arg),
784 void *arg) {
785 ssl_cert_set_cert_cb(ctx->cert, cb, arg);
786 }
787
SSL_set_cert_cb(SSL * ssl,int (* cb)(SSL * ssl,void * arg),void * arg)788 void SSL_set_cert_cb(SSL *ssl, int (*cb)(SSL *ssl, void *arg), void *arg) {
789 ssl_cert_set_cert_cb(ssl->cert, cb, arg);
790 }
791
STACK_OF(CRYPTO_BUFFER)792 STACK_OF(CRYPTO_BUFFER) *SSL_get0_peer_certificates(const SSL *ssl) {
793 SSL_SESSION *session = SSL_get_session(ssl);
794 if (session == NULL) {
795 return NULL;
796 }
797
798 return session->certs;
799 }
800
STACK_OF(CRYPTO_BUFFER)801 STACK_OF(CRYPTO_BUFFER) *SSL_get0_server_requested_CAs(const SSL *ssl) {
802 if (ssl->s3->hs == NULL) {
803 return NULL;
804 }
805 return ssl->s3->hs->ca_names;
806 }
807
ssl_check_leaf_certificate(SSL_HANDSHAKE * hs,EVP_PKEY * pkey,const CRYPTO_BUFFER * leaf)808 int ssl_check_leaf_certificate(SSL_HANDSHAKE *hs, EVP_PKEY *pkey,
809 const CRYPTO_BUFFER *leaf) {
810 SSL *const ssl = hs->ssl;
811 assert(ssl3_protocol_version(ssl) < TLS1_3_VERSION);
812
813 /* Check the certificate's type matches the cipher. */
814 if (!(hs->new_cipher->algorithm_auth & ssl_cipher_auth_mask_for_key(pkey))) {
815 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CERTIFICATE_TYPE);
816 return 0;
817 }
818
819 /* Check key usages for all key types but RSA. This is needed to distinguish
820 * ECDH certificates, which we do not support, from ECDSA certificates. In
821 * principle, we should check RSA key usages based on cipher, but this breaks
822 * buggy antivirus deployments. Other key types are always used for signing.
823 *
824 * TODO(davidben): Get more recent data on RSA key usages. */
825 if (EVP_PKEY_id(pkey) != EVP_PKEY_RSA) {
826 CBS leaf_cbs;
827 CBS_init(&leaf_cbs, CRYPTO_BUFFER_data(leaf), CRYPTO_BUFFER_len(leaf));
828 if (!ssl_cert_check_digital_signature_key_usage(&leaf_cbs)) {
829 return 0;
830 }
831 }
832
833 if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) {
834 /* Check the key's group and point format are acceptable. */
835 EC_KEY *ec_key = EVP_PKEY_get0_EC_KEY(pkey);
836 uint16_t group_id;
837 if (!ssl_nid_to_group_id(
838 &group_id, EC_GROUP_get_curve_name(EC_KEY_get0_group(ec_key))) ||
839 !tls1_check_group_id(ssl, group_id) ||
840 EC_KEY_get_conv_form(ec_key) != POINT_CONVERSION_UNCOMPRESSED) {
841 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_ECC_CERT);
842 return 0;
843 }
844 }
845
846 return 1;
847 }
848
ssl_on_certificate_selected(SSL_HANDSHAKE * hs)849 int ssl_on_certificate_selected(SSL_HANDSHAKE *hs) {
850 SSL *const ssl = hs->ssl;
851 if (!ssl_has_certificate(ssl)) {
852 /* Nothing to do. */
853 return 1;
854 }
855
856 if (!ssl->ctx->x509_method->ssl_auto_chain_if_needed(ssl)) {
857 return 0;
858 }
859
860 CBS leaf;
861 CRYPTO_BUFFER_init_CBS(sk_CRYPTO_BUFFER_value(ssl->cert->chain, 0), &leaf);
862
863 EVP_PKEY_free(hs->local_pubkey);
864 hs->local_pubkey = ssl_cert_parse_pubkey(&leaf);
865 return hs->local_pubkey != NULL;
866 }
867
set_signed_cert_timestamp_list(CERT * cert,const uint8_t * list,size_t list_len)868 static int set_signed_cert_timestamp_list(CERT *cert, const uint8_t *list,
869 size_t list_len) {
870 CBS sct_list;
871 CBS_init(&sct_list, list, list_len);
872 if (!ssl_is_sct_list_valid(&sct_list)) {
873 OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_SCT_LIST);
874 return 0;
875 }
876
877 CRYPTO_BUFFER_free(cert->signed_cert_timestamp_list);
878 cert->signed_cert_timestamp_list =
879 CRYPTO_BUFFER_new(CBS_data(&sct_list), CBS_len(&sct_list), NULL);
880 return cert->signed_cert_timestamp_list != NULL;
881 }
882
SSL_CTX_set_signed_cert_timestamp_list(SSL_CTX * ctx,const uint8_t * list,size_t list_len)883 int SSL_CTX_set_signed_cert_timestamp_list(SSL_CTX *ctx, const uint8_t *list,
884 size_t list_len) {
885 return set_signed_cert_timestamp_list(ctx->cert, list, list_len);
886 }
887
SSL_set_signed_cert_timestamp_list(SSL * ssl,const uint8_t * list,size_t list_len)888 int SSL_set_signed_cert_timestamp_list(SSL *ssl, const uint8_t *list,
889 size_t list_len) {
890 return set_signed_cert_timestamp_list(ssl->cert, list, list_len);
891 }
892
SSL_CTX_set_ocsp_response(SSL_CTX * ctx,const uint8_t * response,size_t response_len)893 int SSL_CTX_set_ocsp_response(SSL_CTX *ctx, const uint8_t *response,
894 size_t response_len) {
895 CRYPTO_BUFFER_free(ctx->cert->ocsp_response);
896 ctx->cert->ocsp_response = CRYPTO_BUFFER_new(response, response_len, NULL);
897 return ctx->cert->ocsp_response != NULL;
898 }
899
SSL_set_ocsp_response(SSL * ssl,const uint8_t * response,size_t response_len)900 int SSL_set_ocsp_response(SSL *ssl, const uint8_t *response,
901 size_t response_len) {
902 CRYPTO_BUFFER_free(ssl->cert->ocsp_response);
903 ssl->cert->ocsp_response = CRYPTO_BUFFER_new(response, response_len, NULL);
904 return ssl->cert->ocsp_response != NULL;
905 }
906