1 /* Copyright (c) 2016, Google Inc.
2 *
3 * Permission to use, copy, modify, and/or distribute this software for any
4 * purpose with or without fee is hereby granted, provided that the above
5 * copyright notice and this permission notice appear in all copies.
6 *
7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14
15 #include <openssl/ssl.h>
16
17 #include <assert.h>
18 #include <string.h>
19
20 #include <utility>
21
22 #include <openssl/bytestring.h>
23 #include <openssl/err.h>
24 #include <openssl/hkdf.h>
25 #include <openssl/mem.h>
26 #include <openssl/stack.h>
27 #include <openssl/x509.h>
28
29 #include "../crypto/internal.h"
30 #include "internal.h"
31
32
33 BSSL_NAMESPACE_BEGIN
34
35 // kMaxKeyUpdates is the number of consecutive KeyUpdates that will be
36 // processed. Without this limit an attacker could force unbounded processing
37 // without being able to return application data.
38 static const uint8_t kMaxKeyUpdates = 32;
39
40 const uint8_t kHelloRetryRequest[SSL3_RANDOM_SIZE] = {
41 0xcf, 0x21, 0xad, 0x74, 0xe5, 0x9a, 0x61, 0x11, 0xbe, 0x1d, 0x8c,
42 0x02, 0x1e, 0x65, 0xb8, 0x91, 0xc2, 0xa2, 0x11, 0x16, 0x7a, 0xbb,
43 0x8c, 0x5e, 0x07, 0x9e, 0x09, 0xe2, 0xc8, 0xa8, 0x33, 0x9c,
44 };
45
46 // See RFC 8446, section 4.1.3.
47 const uint8_t kTLS12DowngradeRandom[8] = {0x44, 0x4f, 0x57, 0x4e,
48 0x47, 0x52, 0x44, 0x00};
49 const uint8_t kTLS13DowngradeRandom[8] = {0x44, 0x4f, 0x57, 0x4e,
50 0x47, 0x52, 0x44, 0x01};
51
52 // This is a non-standard randomly-generated value.
53 const uint8_t kJDK11DowngradeRandom[8] = {0xed, 0xbf, 0xb4, 0xa8,
54 0xc2, 0x47, 0x10, 0xff};
55
tls13_get_cert_verify_signature_input(SSL_HANDSHAKE * hs,Array<uint8_t> * out,enum ssl_cert_verify_context_t cert_verify_context)56 bool tls13_get_cert_verify_signature_input(
57 SSL_HANDSHAKE *hs, Array<uint8_t> *out,
58 enum ssl_cert_verify_context_t cert_verify_context) {
59 ScopedCBB cbb;
60 if (!CBB_init(cbb.get(), 64 + 33 + 1 + 2 * EVP_MAX_MD_SIZE)) {
61 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
62 return false;
63 }
64
65 for (size_t i = 0; i < 64; i++) {
66 if (!CBB_add_u8(cbb.get(), 0x20)) {
67 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
68 return false;
69 }
70 }
71
72 Span<const char> context;
73 if (cert_verify_context == ssl_cert_verify_server) {
74 static const char kContext[] = "TLS 1.3, server CertificateVerify";
75 context = kContext;
76 } else if (cert_verify_context == ssl_cert_verify_client) {
77 static const char kContext[] = "TLS 1.3, client CertificateVerify";
78 context = kContext;
79 } else if (cert_verify_context == ssl_cert_verify_channel_id) {
80 static const char kContext[] = "TLS 1.3, Channel ID";
81 context = kContext;
82 } else {
83 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
84 return false;
85 }
86
87 // Note |context| includes the NUL byte separator.
88 if (!CBB_add_bytes(cbb.get(),
89 reinterpret_cast<const uint8_t *>(context.data()),
90 context.size())) {
91 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
92 return false;
93 }
94
95 uint8_t context_hash[EVP_MAX_MD_SIZE];
96 size_t context_hash_len;
97 if (!hs->transcript.GetHash(context_hash, &context_hash_len) ||
98 !CBB_add_bytes(cbb.get(), context_hash, context_hash_len) ||
99 !CBBFinishArray(cbb.get(), out)) {
100 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
101 return false;
102 }
103
104 return true;
105 }
106
tls13_process_certificate(SSL_HANDSHAKE * hs,const SSLMessage & msg,bool allow_anonymous)107 bool tls13_process_certificate(SSL_HANDSHAKE *hs, const SSLMessage &msg,
108 bool allow_anonymous) {
109 SSL *const ssl = hs->ssl;
110 CBS body = msg.body;
111 bssl::UniquePtr<CRYPTO_BUFFER> decompressed;
112
113 if (msg.type == SSL3_MT_COMPRESSED_CERTIFICATE) {
114 CBS compressed;
115 uint16_t alg_id;
116 uint32_t uncompressed_len;
117
118 if (!CBS_get_u16(&body, &alg_id) ||
119 !CBS_get_u24(&body, &uncompressed_len) ||
120 !CBS_get_u24_length_prefixed(&body, &compressed) ||
121 CBS_len(&body) != 0) {
122 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
123 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
124 return false;
125 }
126
127 if (uncompressed_len > ssl->max_cert_list) {
128 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
129 OPENSSL_PUT_ERROR(SSL, SSL_R_UNCOMPRESSED_CERT_TOO_LARGE);
130 ERR_add_error_dataf("requested=%u",
131 static_cast<unsigned>(uncompressed_len));
132 return false;
133 }
134
135 ssl_cert_decompression_func_t decompress = nullptr;
136 for (const auto &alg : ssl->ctx->cert_compression_algs) {
137 if (alg.alg_id == alg_id) {
138 decompress = alg.decompress;
139 break;
140 }
141 }
142
143 if (decompress == nullptr) {
144 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
145 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CERT_COMPRESSION_ALG);
146 ERR_add_error_dataf("alg=%d", static_cast<int>(alg_id));
147 return false;
148 }
149
150 CRYPTO_BUFFER *decompressed_ptr = nullptr;
151 if (!decompress(ssl, &decompressed_ptr, uncompressed_len,
152 CBS_data(&compressed), CBS_len(&compressed))) {
153 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
154 OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_DECOMPRESSION_FAILED);
155 ERR_add_error_dataf("alg=%d", static_cast<int>(alg_id));
156 return false;
157 }
158 decompressed.reset(decompressed_ptr);
159
160 if (CRYPTO_BUFFER_len(decompressed_ptr) != uncompressed_len) {
161 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
162 OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_DECOMPRESSION_FAILED);
163 ERR_add_error_dataf(
164 "alg=%d got=%u expected=%u", static_cast<int>(alg_id),
165 static_cast<unsigned>(CRYPTO_BUFFER_len(decompressed_ptr)),
166 static_cast<unsigned>(uncompressed_len));
167 return false;
168 }
169
170 CBS_init(&body, CRYPTO_BUFFER_data(decompressed_ptr),
171 CRYPTO_BUFFER_len(decompressed_ptr));
172 } else {
173 assert(msg.type == SSL3_MT_CERTIFICATE);
174 }
175
176 CBS context, certificate_list;
177 if (!CBS_get_u8_length_prefixed(&body, &context) ||
178 CBS_len(&context) != 0 ||
179 !CBS_get_u24_length_prefixed(&body, &certificate_list) ||
180 CBS_len(&body) != 0) {
181 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
182 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
183 return false;
184 }
185
186 UniquePtr<STACK_OF(CRYPTO_BUFFER)> certs(sk_CRYPTO_BUFFER_new_null());
187 if (!certs) {
188 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
189 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
190 return false;
191 }
192
193 const bool retain_sha256 =
194 ssl->server && hs->config->retain_only_sha256_of_client_certs;
195 UniquePtr<EVP_PKEY> pkey;
196 while (CBS_len(&certificate_list) > 0) {
197 CBS certificate, extensions;
198 if (!CBS_get_u24_length_prefixed(&certificate_list, &certificate) ||
199 !CBS_get_u16_length_prefixed(&certificate_list, &extensions) ||
200 CBS_len(&certificate) == 0) {
201 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
202 OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_LENGTH_MISMATCH);
203 return false;
204 }
205
206 if (sk_CRYPTO_BUFFER_num(certs.get()) == 0) {
207 pkey = ssl_cert_parse_pubkey(&certificate);
208 if (!pkey) {
209 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
210 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
211 return false;
212 }
213 // TLS 1.3 always uses certificate keys for signing thus the correct
214 // keyUsage is enforced.
215 if (!ssl_cert_check_key_usage(&certificate,
216 key_usage_digital_signature)) {
217 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
218 return false;
219 }
220
221 if (retain_sha256) {
222 // Retain the hash of the leaf certificate if requested.
223 SHA256(CBS_data(&certificate), CBS_len(&certificate),
224 hs->new_session->peer_sha256);
225 }
226 }
227
228 UniquePtr<CRYPTO_BUFFER> buf(
229 CRYPTO_BUFFER_new_from_CBS(&certificate, ssl->ctx->pool));
230 if (!buf ||
231 !PushToStack(certs.get(), std::move(buf))) {
232 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
233 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
234 return false;
235 }
236
237 // Parse out the extensions.
238 bool have_status_request = false, have_sct = false;
239 CBS status_request, sct;
240 const SSL_EXTENSION_TYPE ext_types[] = {
241 {TLSEXT_TYPE_status_request, &have_status_request, &status_request},
242 {TLSEXT_TYPE_certificate_timestamp, &have_sct, &sct},
243 };
244
245 uint8_t alert = SSL_AD_DECODE_ERROR;
246 if (!ssl_parse_extensions(&extensions, &alert, ext_types,
247 OPENSSL_ARRAY_SIZE(ext_types),
248 0 /* reject unknown */)) {
249 ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
250 return false;
251 }
252
253 // All Certificate extensions are parsed, but only the leaf extensions are
254 // stored.
255 if (have_status_request) {
256 if (ssl->server || !hs->config->ocsp_stapling_enabled) {
257 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION);
258 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION);
259 return false;
260 }
261
262 uint8_t status_type;
263 CBS ocsp_response;
264 if (!CBS_get_u8(&status_request, &status_type) ||
265 status_type != TLSEXT_STATUSTYPE_ocsp ||
266 !CBS_get_u24_length_prefixed(&status_request, &ocsp_response) ||
267 CBS_len(&ocsp_response) == 0 ||
268 CBS_len(&status_request) != 0) {
269 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
270 return false;
271 }
272
273 if (sk_CRYPTO_BUFFER_num(certs.get()) == 1) {
274 hs->new_session->ocsp_response.reset(
275 CRYPTO_BUFFER_new_from_CBS(&ocsp_response, ssl->ctx->pool));
276 if (hs->new_session->ocsp_response == nullptr) {
277 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
278 return false;
279 }
280 }
281 }
282
283 if (have_sct) {
284 if (ssl->server || !hs->config->signed_cert_timestamps_enabled) {
285 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION);
286 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION);
287 return false;
288 }
289
290 if (!ssl_is_sct_list_valid(&sct)) {
291 OPENSSL_PUT_ERROR(SSL, SSL_R_ERROR_PARSING_EXTENSION);
292 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
293 return false;
294 }
295
296 if (sk_CRYPTO_BUFFER_num(certs.get()) == 1) {
297 hs->new_session->signed_cert_timestamp_list.reset(
298 CRYPTO_BUFFER_new_from_CBS(&sct, ssl->ctx->pool));
299 if (hs->new_session->signed_cert_timestamp_list == nullptr) {
300 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
301 return false;
302 }
303 }
304 }
305 }
306
307 // Store a null certificate list rather than an empty one if the peer didn't
308 // send certificates.
309 if (sk_CRYPTO_BUFFER_num(certs.get()) == 0) {
310 certs.reset();
311 }
312
313 hs->peer_pubkey = std::move(pkey);
314 hs->new_session->certs = std::move(certs);
315
316 if (!ssl->ctx->x509_method->session_cache_objects(hs->new_session.get())) {
317 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
318 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
319 return false;
320 }
321
322 if (sk_CRYPTO_BUFFER_num(hs->new_session->certs.get()) == 0) {
323 if (!allow_anonymous) {
324 OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
325 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_CERTIFICATE_REQUIRED);
326 return false;
327 }
328
329 // OpenSSL returns X509_V_OK when no certificates are requested. This is
330 // classed by them as a bug, but it's assumed by at least NGINX.
331 hs->new_session->verify_result = X509_V_OK;
332
333 // No certificate, so nothing more to do.
334 return true;
335 }
336
337 hs->new_session->peer_sha256_valid = retain_sha256;
338 return true;
339 }
340
tls13_process_certificate_verify(SSL_HANDSHAKE * hs,const SSLMessage & msg)341 bool tls13_process_certificate_verify(SSL_HANDSHAKE *hs, const SSLMessage &msg) {
342 SSL *const ssl = hs->ssl;
343 if (hs->peer_pubkey == NULL) {
344 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
345 return false;
346 }
347
348 CBS body = msg.body, signature;
349 uint16_t signature_algorithm;
350 if (!CBS_get_u16(&body, &signature_algorithm) ||
351 !CBS_get_u16_length_prefixed(&body, &signature) ||
352 CBS_len(&body) != 0) {
353 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
354 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
355 return false;
356 }
357
358 uint8_t alert = SSL_AD_DECODE_ERROR;
359 if (!tls12_check_peer_sigalg(ssl, &alert, signature_algorithm)) {
360 ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
361 return false;
362 }
363 hs->new_session->peer_signature_algorithm = signature_algorithm;
364
365 Array<uint8_t> input;
366 if (!tls13_get_cert_verify_signature_input(
367 hs, &input,
368 ssl->server ? ssl_cert_verify_client : ssl_cert_verify_server)) {
369 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
370 return false;
371 }
372
373 if (!ssl_public_key_verify(ssl, signature, signature_algorithm,
374 hs->peer_pubkey.get(), input)) {
375 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_SIGNATURE);
376 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR);
377 return false;
378 }
379
380 return true;
381 }
382
tls13_process_finished(SSL_HANDSHAKE * hs,const SSLMessage & msg,bool use_saved_value)383 bool tls13_process_finished(SSL_HANDSHAKE *hs, const SSLMessage &msg,
384 bool use_saved_value) {
385 SSL *const ssl = hs->ssl;
386 uint8_t verify_data_buf[EVP_MAX_MD_SIZE];
387 Span<const uint8_t> verify_data;
388 if (use_saved_value) {
389 assert(ssl->server);
390 verify_data = hs->expected_client_finished();
391 } else {
392 size_t len;
393 if (!tls13_finished_mac(hs, verify_data_buf, &len, !ssl->server)) {
394 return false;
395 }
396 verify_data = MakeConstSpan(verify_data_buf, len);
397 }
398
399 bool finished_ok =
400 CBS_mem_equal(&msg.body, verify_data.data(), verify_data.size());
401 #if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
402 finished_ok = true;
403 #endif
404 if (!finished_ok) {
405 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR);
406 OPENSSL_PUT_ERROR(SSL, SSL_R_DIGEST_CHECK_FAILED);
407 return false;
408 }
409
410 return true;
411 }
412
tls13_add_certificate(SSL_HANDSHAKE * hs)413 bool tls13_add_certificate(SSL_HANDSHAKE *hs) {
414 SSL *const ssl = hs->ssl;
415 CERT *const cert = hs->config->cert.get();
416 DC *const dc = cert->dc.get();
417
418 ScopedCBB cbb;
419 CBB *body, body_storage, certificate_list;
420
421 if (hs->cert_compression_negotiated) {
422 if (!CBB_init(cbb.get(), 1024)) {
423 return false;
424 }
425 body = cbb.get();
426 } else {
427 body = &body_storage;
428 if (!ssl->method->init_message(ssl, cbb.get(), body, SSL3_MT_CERTIFICATE)) {
429 return false;
430 }
431 }
432
433 if (// The request context is always empty in the handshake.
434 !CBB_add_u8(body, 0) ||
435 !CBB_add_u24_length_prefixed(body, &certificate_list)) {
436 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
437 return false;
438 }
439
440 if (!ssl_has_certificate(hs)) {
441 return ssl_add_message_cbb(ssl, cbb.get());
442 }
443
444 CRYPTO_BUFFER *leaf_buf = sk_CRYPTO_BUFFER_value(cert->chain.get(), 0);
445 CBB leaf, extensions;
446 if (!CBB_add_u24_length_prefixed(&certificate_list, &leaf) ||
447 !CBB_add_bytes(&leaf, CRYPTO_BUFFER_data(leaf_buf),
448 CRYPTO_BUFFER_len(leaf_buf)) ||
449 !CBB_add_u16_length_prefixed(&certificate_list, &extensions)) {
450 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
451 return false;
452 }
453
454 if (hs->scts_requested && cert->signed_cert_timestamp_list != nullptr) {
455 CBB contents;
456 if (!CBB_add_u16(&extensions, TLSEXT_TYPE_certificate_timestamp) ||
457 !CBB_add_u16_length_prefixed(&extensions, &contents) ||
458 !CBB_add_bytes(
459 &contents,
460 CRYPTO_BUFFER_data(cert->signed_cert_timestamp_list.get()),
461 CRYPTO_BUFFER_len(cert->signed_cert_timestamp_list.get())) ||
462 !CBB_flush(&extensions)) {
463 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
464 return false;
465 }
466 }
467
468 if (hs->ocsp_stapling_requested && cert->ocsp_response != NULL) {
469 CBB contents, ocsp_response;
470 if (!CBB_add_u16(&extensions, TLSEXT_TYPE_status_request) ||
471 !CBB_add_u16_length_prefixed(&extensions, &contents) ||
472 !CBB_add_u8(&contents, TLSEXT_STATUSTYPE_ocsp) ||
473 !CBB_add_u24_length_prefixed(&contents, &ocsp_response) ||
474 !CBB_add_bytes(&ocsp_response,
475 CRYPTO_BUFFER_data(cert->ocsp_response.get()),
476 CRYPTO_BUFFER_len(cert->ocsp_response.get())) ||
477 !CBB_flush(&extensions)) {
478 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
479 return false;
480 }
481 }
482
483 if (ssl_signing_with_dc(hs)) {
484 const CRYPTO_BUFFER *raw = dc->raw.get();
485 CBB child;
486 if (!CBB_add_u16(&extensions, TLSEXT_TYPE_delegated_credential) ||
487 !CBB_add_u16_length_prefixed(&extensions, &child) ||
488 !CBB_add_bytes(&child, CRYPTO_BUFFER_data(raw),
489 CRYPTO_BUFFER_len(raw)) ||
490 !CBB_flush(&extensions)) {
491 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
492 return 0;
493 }
494 ssl->s3->delegated_credential_used = true;
495 }
496
497 for (size_t i = 1; i < sk_CRYPTO_BUFFER_num(cert->chain.get()); i++) {
498 CRYPTO_BUFFER *cert_buf = sk_CRYPTO_BUFFER_value(cert->chain.get(), i);
499 CBB child;
500 if (!CBB_add_u24_length_prefixed(&certificate_list, &child) ||
501 !CBB_add_bytes(&child, CRYPTO_BUFFER_data(cert_buf),
502 CRYPTO_BUFFER_len(cert_buf)) ||
503 !CBB_add_u16(&certificate_list, 0 /* no extensions */)) {
504 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
505 return false;
506 }
507 }
508
509 if (!hs->cert_compression_negotiated) {
510 return ssl_add_message_cbb(ssl, cbb.get());
511 }
512
513 Array<uint8_t> msg;
514 if (!CBBFinishArray(cbb.get(), &msg)) {
515 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
516 return false;
517 }
518
519 const CertCompressionAlg *alg = nullptr;
520 for (const auto &candidate : ssl->ctx->cert_compression_algs) {
521 if (candidate.alg_id == hs->cert_compression_alg_id) {
522 alg = &candidate;
523 break;
524 }
525 }
526
527 if (alg == nullptr || alg->compress == nullptr) {
528 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
529 return false;
530 }
531
532 CBB compressed;
533 body = &body_storage;
534 if (!ssl->method->init_message(ssl, cbb.get(), body,
535 SSL3_MT_COMPRESSED_CERTIFICATE) ||
536 !CBB_add_u16(body, hs->cert_compression_alg_id) ||
537 !CBB_add_u24(body, msg.size()) ||
538 !CBB_add_u24_length_prefixed(body, &compressed) ||
539 !alg->compress(ssl, &compressed, msg.data(), msg.size()) ||
540 !ssl_add_message_cbb(ssl, cbb.get())) {
541 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
542 return false;
543 }
544
545 return true;
546 }
547
tls13_add_certificate_verify(SSL_HANDSHAKE * hs)548 enum ssl_private_key_result_t tls13_add_certificate_verify(SSL_HANDSHAKE *hs) {
549 SSL *const ssl = hs->ssl;
550 uint16_t signature_algorithm;
551 if (!tls1_choose_signature_algorithm(hs, &signature_algorithm)) {
552 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
553 return ssl_private_key_failure;
554 }
555
556 ScopedCBB cbb;
557 CBB body;
558 if (!ssl->method->init_message(ssl, cbb.get(), &body,
559 SSL3_MT_CERTIFICATE_VERIFY) ||
560 !CBB_add_u16(&body, signature_algorithm)) {
561 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
562 return ssl_private_key_failure;
563 }
564
565 // Sign the digest.
566 CBB child;
567 const size_t max_sig_len = EVP_PKEY_size(hs->local_pubkey.get());
568 uint8_t *sig;
569 size_t sig_len;
570 if (!CBB_add_u16_length_prefixed(&body, &child) ||
571 !CBB_reserve(&child, &sig, max_sig_len)) {
572 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
573 return ssl_private_key_failure;
574 }
575
576 Array<uint8_t> msg;
577 if (!tls13_get_cert_verify_signature_input(
578 hs, &msg,
579 ssl->server ? ssl_cert_verify_server : ssl_cert_verify_client)) {
580 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
581 return ssl_private_key_failure;
582 }
583
584 enum ssl_private_key_result_t sign_result = ssl_private_key_sign(
585 hs, sig, &sig_len, max_sig_len, signature_algorithm, msg);
586 if (sign_result != ssl_private_key_success) {
587 return sign_result;
588 }
589
590 if (!CBB_did_write(&child, sig_len) ||
591 !ssl_add_message_cbb(ssl, cbb.get())) {
592 return ssl_private_key_failure;
593 }
594
595 return ssl_private_key_success;
596 }
597
tls13_add_finished(SSL_HANDSHAKE * hs)598 bool tls13_add_finished(SSL_HANDSHAKE *hs) {
599 SSL *const ssl = hs->ssl;
600 size_t verify_data_len;
601 uint8_t verify_data[EVP_MAX_MD_SIZE];
602
603 if (!tls13_finished_mac(hs, verify_data, &verify_data_len, ssl->server)) {
604 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
605 OPENSSL_PUT_ERROR(SSL, SSL_R_DIGEST_CHECK_FAILED);
606 return false;
607 }
608
609 ScopedCBB cbb;
610 CBB body;
611 if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_FINISHED) ||
612 !CBB_add_bytes(&body, verify_data, verify_data_len) ||
613 !ssl_add_message_cbb(ssl, cbb.get())) {
614 return false;
615 }
616
617 return true;
618 }
619
tls13_add_key_update(SSL * ssl,int update_requested)620 bool tls13_add_key_update(SSL *ssl, int update_requested) {
621 ScopedCBB cbb;
622 CBB body_cbb;
623 if (!ssl->method->init_message(ssl, cbb.get(), &body_cbb,
624 SSL3_MT_KEY_UPDATE) ||
625 !CBB_add_u8(&body_cbb, update_requested) ||
626 !ssl_add_message_cbb(ssl, cbb.get()) ||
627 !tls13_rotate_traffic_key(ssl, evp_aead_seal)) {
628 return false;
629 }
630
631 // Suppress KeyUpdate acknowledgments until this change is written to the
632 // wire. This prevents us from accumulating write obligations when read and
633 // write progress at different rates. See RFC 8446, section 4.6.3.
634 ssl->s3->key_update_pending = true;
635
636 return true;
637 }
638
tls13_receive_key_update(SSL * ssl,const SSLMessage & msg)639 static bool tls13_receive_key_update(SSL *ssl, const SSLMessage &msg) {
640 CBS body = msg.body;
641 uint8_t key_update_request;
642 if (!CBS_get_u8(&body, &key_update_request) ||
643 CBS_len(&body) != 0 ||
644 (key_update_request != SSL_KEY_UPDATE_NOT_REQUESTED &&
645 key_update_request != SSL_KEY_UPDATE_REQUESTED)) {
646 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
647 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
648 return false;
649 }
650
651 if (!tls13_rotate_traffic_key(ssl, evp_aead_open)) {
652 return false;
653 }
654
655 // Acknowledge the KeyUpdate
656 if (key_update_request == SSL_KEY_UPDATE_REQUESTED &&
657 !ssl->s3->key_update_pending &&
658 !tls13_add_key_update(ssl, SSL_KEY_UPDATE_NOT_REQUESTED)) {
659 return false;
660 }
661
662 return true;
663 }
664
tls13_post_handshake(SSL * ssl,const SSLMessage & msg)665 bool tls13_post_handshake(SSL *ssl, const SSLMessage &msg) {
666 if (msg.type == SSL3_MT_KEY_UPDATE) {
667 ssl->s3->key_update_count++;
668 if (ssl->quic_method != nullptr ||
669 ssl->s3->key_update_count > kMaxKeyUpdates) {
670 OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_KEY_UPDATES);
671 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
672 return false;
673 }
674
675 return tls13_receive_key_update(ssl, msg);
676 }
677
678 ssl->s3->key_update_count = 0;
679
680 if (msg.type == SSL3_MT_NEW_SESSION_TICKET && !ssl->server) {
681 return tls13_process_new_session_ticket(ssl, msg);
682 }
683
684 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
685 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
686 return false;
687 }
688
689 BSSL_NAMESPACE_END
690