1/*
2 * Copyright 1995-2022 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
4 * Copyright 2005 Nokia. All rights reserved.
5 *
6 * Licensed under the Apache License 2.0 (the "License").  You may not use
7 * this file except in compliance with the License.  You can obtain a copy
8 * in the file LICENSE in the source distribution or at
9 * https://www.openssl.org/source/license.html
10 */
11
12#include <stdio.h>
13#include <time.h>
14#include <assert.h>
15#include "../ssl_local.h"
16#include "statem_local.h"
17#include <openssl/buffer.h>
18#include <openssl/rand.h>
19#include <openssl/objects.h>
20#include <openssl/evp.h>
21#include <openssl/md5.h>
22#include <openssl/dh.h>
23#include <openssl/rsa.h>
24#include <openssl/bn.h>
25#include <openssl/engine.h>
26#include <openssl/trace.h>
27#include <openssl/core_names.h>
28#include <openssl/param_build.h>
29#include "internal/cryptlib.h"
30
31static MSG_PROCESS_RETURN tls_process_as_hello_retry_request(SSL *s, PACKET *pkt);
32static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL *s, PACKET *pkt);
33
34static ossl_inline int cert_req_allowed(SSL *s);
35static int key_exchange_expected(SSL *s);
36static int ssl_cipher_list_to_bytes(SSL *s, STACK_OF(SSL_CIPHER) *sk,
37                                    WPACKET *pkt);
38
39/*
40 * Is a CertificateRequest message allowed at the moment or not?
41 *
42 *  Return values are:
43 *  1: Yes
44 *  0: No
45 */
46static ossl_inline int cert_req_allowed(SSL *s)
47{
48    /* TLS does not like anon-DH with client cert */
49    if ((s->version > SSL3_VERSION
50         && (s->s3.tmp.new_cipher->algorithm_auth & SSL_aNULL))
51        || (s->s3.tmp.new_cipher->algorithm_auth & (SSL_aSRP | SSL_aPSK)))
52        return 0;
53
54    return 1;
55}
56
57/*
58 * Should we expect the ServerKeyExchange message or not?
59 *
60 *  Return values are:
61 *  1: Yes
62 *  0: No
63 */
64static int key_exchange_expected(SSL *s)
65{
66    long alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
67
68    /*
69     * Can't skip server key exchange if this is an ephemeral
70     * ciphersuite or for SRP
71     */
72    if (alg_k & (SSL_kDHE | SSL_kECDHE | SSL_kDHEPSK | SSL_kECDHEPSK
73                 | SSL_kSRP)) {
74        return 1;
75    }
76
77    return 0;
78}
79
80/*
81 * ossl_statem_client_read_transition() encapsulates the logic for the allowed
82 * handshake state transitions when a TLS1.3 client is reading messages from the
83 * server. The message type that the server has sent is provided in |mt|. The
84 * current state is in |s->statem.hand_state|.
85 *
86 * Return values are 1 for success (transition allowed) and  0 on error
87 * (transition not allowed)
88 */
89static int ossl_statem_client13_read_transition(SSL *s, int mt)
90{
91    OSSL_STATEM *st = &s->statem;
92
93    /*
94     * Note: There is no case for TLS_ST_CW_CLNT_HELLO, because we haven't
95     * yet negotiated TLSv1.3 at that point so that is handled by
96     * ossl_statem_client_read_transition()
97     */
98
99    switch (st->hand_state) {
100    default:
101        break;
102
103    case TLS_ST_CW_CLNT_HELLO:
104        /*
105         * This must a ClientHello following a HelloRetryRequest, so the only
106         * thing we can get now is a ServerHello.
107         */
108        if (mt == SSL3_MT_SERVER_HELLO) {
109            st->hand_state = TLS_ST_CR_SRVR_HELLO;
110            return 1;
111        }
112        break;
113
114    case TLS_ST_CR_SRVR_HELLO:
115        if (mt == SSL3_MT_ENCRYPTED_EXTENSIONS) {
116            st->hand_state = TLS_ST_CR_ENCRYPTED_EXTENSIONS;
117            return 1;
118        }
119        break;
120
121    case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
122        if (s->hit) {
123            if (mt == SSL3_MT_FINISHED) {
124                st->hand_state = TLS_ST_CR_FINISHED;
125                return 1;
126            }
127        } else {
128            if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
129                st->hand_state = TLS_ST_CR_CERT_REQ;
130                return 1;
131            }
132            if (mt == SSL3_MT_CERTIFICATE) {
133                st->hand_state = TLS_ST_CR_CERT;
134                return 1;
135            }
136        }
137        break;
138
139    case TLS_ST_CR_CERT_REQ:
140        if (mt == SSL3_MT_CERTIFICATE) {
141            st->hand_state = TLS_ST_CR_CERT;
142            return 1;
143        }
144        break;
145
146    case TLS_ST_CR_CERT:
147        if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
148            st->hand_state = TLS_ST_CR_CERT_VRFY;
149            return 1;
150        }
151        break;
152
153    case TLS_ST_CR_CERT_VRFY:
154        if (mt == SSL3_MT_FINISHED) {
155            st->hand_state = TLS_ST_CR_FINISHED;
156            return 1;
157        }
158        break;
159
160    case TLS_ST_OK:
161        if (mt == SSL3_MT_NEWSESSION_TICKET) {
162            st->hand_state = TLS_ST_CR_SESSION_TICKET;
163            return 1;
164        }
165        if (mt == SSL3_MT_KEY_UPDATE) {
166            st->hand_state = TLS_ST_CR_KEY_UPDATE;
167            return 1;
168        }
169        if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
170#if DTLS_MAX_VERSION_INTERNAL != DTLS1_2_VERSION
171            /* Restore digest for PHA before adding message.*/
172# error Internal DTLS version error
173#endif
174            if (!SSL_IS_DTLS(s) && s->post_handshake_auth == SSL_PHA_EXT_SENT) {
175                s->post_handshake_auth = SSL_PHA_REQUESTED;
176                /*
177                 * In TLS, this is called before the message is added to the
178                 * digest. In DTLS, this is expected to be called after adding
179                 * to the digest. Either move the digest restore, or add the
180                 * message here after the swap, or do it after the clientFinished?
181                 */
182                if (!tls13_restore_handshake_digest_for_pha(s)) {
183                    /* SSLfatal() already called */
184                    return 0;
185                }
186                st->hand_state = TLS_ST_CR_CERT_REQ;
187                return 1;
188            }
189        }
190        break;
191    }
192
193    /* No valid transition found */
194    return 0;
195}
196
197/*
198 * ossl_statem_client_read_transition() encapsulates the logic for the allowed
199 * handshake state transitions when the client is reading messages from the
200 * server. The message type that the server has sent is provided in |mt|. The
201 * current state is in |s->statem.hand_state|.
202 *
203 * Return values are 1 for success (transition allowed) and  0 on error
204 * (transition not allowed)
205 */
206int ossl_statem_client_read_transition(SSL *s, int mt)
207{
208    OSSL_STATEM *st = &s->statem;
209    int ske_expected;
210
211    /*
212     * Note that after writing the first ClientHello we don't know what version
213     * we are going to negotiate yet, so we don't take this branch until later.
214     */
215    if (SSL_IS_TLS13(s)) {
216        if (!ossl_statem_client13_read_transition(s, mt))
217            goto err;
218        return 1;
219    }
220
221    switch (st->hand_state) {
222    default:
223        break;
224
225    case TLS_ST_CW_CLNT_HELLO:
226        if (mt == SSL3_MT_SERVER_HELLO) {
227            st->hand_state = TLS_ST_CR_SRVR_HELLO;
228            return 1;
229        }
230
231        if (SSL_IS_DTLS(s)) {
232            if (mt == DTLS1_MT_HELLO_VERIFY_REQUEST) {
233                st->hand_state = DTLS_ST_CR_HELLO_VERIFY_REQUEST;
234                return 1;
235            }
236        }
237        break;
238
239    case TLS_ST_EARLY_DATA:
240        /*
241         * We've not actually selected TLSv1.3 yet, but we have sent early
242         * data. The only thing allowed now is a ServerHello or a
243         * HelloRetryRequest.
244         */
245        if (mt == SSL3_MT_SERVER_HELLO) {
246            st->hand_state = TLS_ST_CR_SRVR_HELLO;
247            return 1;
248        }
249        break;
250
251    case TLS_ST_CR_SRVR_HELLO:
252        if (s->hit) {
253            if (s->ext.ticket_expected) {
254                if (mt == SSL3_MT_NEWSESSION_TICKET) {
255                    st->hand_state = TLS_ST_CR_SESSION_TICKET;
256                    return 1;
257                }
258            } else if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
259                st->hand_state = TLS_ST_CR_CHANGE;
260                return 1;
261            }
262        } else {
263            if (SSL_IS_DTLS(s) && mt == DTLS1_MT_HELLO_VERIFY_REQUEST) {
264                st->hand_state = DTLS_ST_CR_HELLO_VERIFY_REQUEST;
265                return 1;
266            } else if (s->version >= TLS1_VERSION
267                       && s->ext.session_secret_cb != NULL
268                       && s->session->ext.tick != NULL
269                       && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
270                /*
271                 * Normally, we can tell if the server is resuming the session
272                 * from the session ID. EAP-FAST (RFC 4851), however, relies on
273                 * the next server message after the ServerHello to determine if
274                 * the server is resuming.
275                 */
276                s->hit = 1;
277                st->hand_state = TLS_ST_CR_CHANGE;
278                return 1;
279            } else if (!(s->s3.tmp.new_cipher->algorithm_auth
280                         & (SSL_aNULL | SSL_aSRP | SSL_aPSK))) {
281                if (mt == SSL3_MT_CERTIFICATE) {
282                    st->hand_state = TLS_ST_CR_CERT;
283                    return 1;
284                }
285            } else {
286                ske_expected = key_exchange_expected(s);
287                /* SKE is optional for some PSK ciphersuites */
288                if (ske_expected
289                    || ((s->s3.tmp.new_cipher->algorithm_mkey & SSL_PSK)
290                        && mt == SSL3_MT_SERVER_KEY_EXCHANGE)) {
291                    if (mt == SSL3_MT_SERVER_KEY_EXCHANGE) {
292                        st->hand_state = TLS_ST_CR_KEY_EXCH;
293                        return 1;
294                    }
295                } else if (mt == SSL3_MT_CERTIFICATE_REQUEST
296                           && cert_req_allowed(s)) {
297                    st->hand_state = TLS_ST_CR_CERT_REQ;
298                    return 1;
299                } else if (mt == SSL3_MT_SERVER_DONE) {
300                    st->hand_state = TLS_ST_CR_SRVR_DONE;
301                    return 1;
302                }
303            }
304        }
305        break;
306
307    case TLS_ST_CR_CERT:
308        /*
309         * The CertificateStatus message is optional even if
310         * |ext.status_expected| is set
311         */
312        if (s->ext.status_expected && mt == SSL3_MT_CERTIFICATE_STATUS) {
313            st->hand_state = TLS_ST_CR_CERT_STATUS;
314            return 1;
315        }
316        /* Fall through */
317
318    case TLS_ST_CR_CERT_STATUS:
319        ske_expected = key_exchange_expected(s);
320        /* SKE is optional for some PSK ciphersuites */
321        if (ske_expected || ((s->s3.tmp.new_cipher->algorithm_mkey & SSL_PSK)
322                             && mt == SSL3_MT_SERVER_KEY_EXCHANGE)) {
323            if (mt == SSL3_MT_SERVER_KEY_EXCHANGE) {
324                st->hand_state = TLS_ST_CR_KEY_EXCH;
325                return 1;
326            }
327            goto err;
328        }
329        /* Fall through */
330
331    case TLS_ST_CR_KEY_EXCH:
332        if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
333            if (cert_req_allowed(s)) {
334                st->hand_state = TLS_ST_CR_CERT_REQ;
335                return 1;
336            }
337            goto err;
338        }
339        /* Fall through */
340
341    case TLS_ST_CR_CERT_REQ:
342        if (mt == SSL3_MT_SERVER_DONE) {
343            st->hand_state = TLS_ST_CR_SRVR_DONE;
344            return 1;
345        }
346        break;
347
348    case TLS_ST_CW_FINISHED:
349        if (s->ext.ticket_expected) {
350            if (mt == SSL3_MT_NEWSESSION_TICKET) {
351                st->hand_state = TLS_ST_CR_SESSION_TICKET;
352                return 1;
353            }
354        } else if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
355            st->hand_state = TLS_ST_CR_CHANGE;
356            return 1;
357        }
358        break;
359
360    case TLS_ST_CR_SESSION_TICKET:
361        if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
362            st->hand_state = TLS_ST_CR_CHANGE;
363            return 1;
364        }
365        break;
366
367    case TLS_ST_CR_CHANGE:
368        if (mt == SSL3_MT_FINISHED) {
369            st->hand_state = TLS_ST_CR_FINISHED;
370            return 1;
371        }
372        break;
373
374    case TLS_ST_OK:
375        if (mt == SSL3_MT_HELLO_REQUEST) {
376            st->hand_state = TLS_ST_CR_HELLO_REQ;
377            return 1;
378        }
379        break;
380    }
381
382 err:
383    /* No valid transition found */
384    if (SSL_IS_DTLS(s) && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
385        BIO *rbio;
386
387        /*
388         * CCS messages don't have a message sequence number so this is probably
389         * because of an out-of-order CCS. We'll just drop it.
390         */
391        s->init_num = 0;
392        s->rwstate = SSL_READING;
393        rbio = SSL_get_rbio(s);
394        BIO_clear_retry_flags(rbio);
395        BIO_set_retry_read(rbio);
396        return 0;
397    }
398    SSLfatal(s, SSL3_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
399    return 0;
400}
401
402/*
403 * ossl_statem_client13_write_transition() works out what handshake state to
404 * move to next when the TLSv1.3 client is writing messages to be sent to the
405 * server.
406 */
407static WRITE_TRAN ossl_statem_client13_write_transition(SSL *s)
408{
409    OSSL_STATEM *st = &s->statem;
410
411    /*
412     * Note: There are no cases for TLS_ST_BEFORE because we haven't negotiated
413     * TLSv1.3 yet at that point. They are handled by
414     * ossl_statem_client_write_transition().
415     */
416    switch (st->hand_state) {
417    default:
418        /* Shouldn't happen */
419        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
420        return WRITE_TRAN_ERROR;
421
422    case TLS_ST_CR_CERT_REQ:
423        if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
424            st->hand_state = TLS_ST_CW_CERT;
425            return WRITE_TRAN_CONTINUE;
426        }
427        /*
428         * We should only get here if we received a CertificateRequest after
429         * we already sent close_notify
430         */
431        if (!ossl_assert((s->shutdown & SSL_SENT_SHUTDOWN) != 0)) {
432            /* Shouldn't happen - same as default case */
433            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
434            return WRITE_TRAN_ERROR;
435        }
436        st->hand_state = TLS_ST_OK;
437        return WRITE_TRAN_CONTINUE;
438
439    case TLS_ST_CR_FINISHED:
440        if (s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY
441                || s->early_data_state == SSL_EARLY_DATA_FINISHED_WRITING)
442            st->hand_state = TLS_ST_PENDING_EARLY_DATA_END;
443        else if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
444                 && s->hello_retry_request == SSL_HRR_NONE)
445            st->hand_state = TLS_ST_CW_CHANGE;
446        else
447            st->hand_state = (s->s3.tmp.cert_req != 0) ? TLS_ST_CW_CERT
448                                                        : TLS_ST_CW_FINISHED;
449        return WRITE_TRAN_CONTINUE;
450
451    case TLS_ST_PENDING_EARLY_DATA_END:
452        if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED) {
453            st->hand_state = TLS_ST_CW_END_OF_EARLY_DATA;
454            return WRITE_TRAN_CONTINUE;
455        }
456        /* Fall through */
457
458    case TLS_ST_CW_END_OF_EARLY_DATA:
459    case TLS_ST_CW_CHANGE:
460        st->hand_state = (s->s3.tmp.cert_req != 0) ? TLS_ST_CW_CERT
461                                                    : TLS_ST_CW_FINISHED;
462        return WRITE_TRAN_CONTINUE;
463
464    case TLS_ST_CW_CERT:
465        /* If a non-empty Certificate we also send CertificateVerify */
466        st->hand_state = (s->s3.tmp.cert_req == 1) ? TLS_ST_CW_CERT_VRFY
467                                                    : TLS_ST_CW_FINISHED;
468        return WRITE_TRAN_CONTINUE;
469
470    case TLS_ST_CW_CERT_VRFY:
471        st->hand_state = TLS_ST_CW_FINISHED;
472        return WRITE_TRAN_CONTINUE;
473
474    case TLS_ST_CR_KEY_UPDATE:
475    case TLS_ST_CW_KEY_UPDATE:
476    case TLS_ST_CR_SESSION_TICKET:
477    case TLS_ST_CW_FINISHED:
478        st->hand_state = TLS_ST_OK;
479        return WRITE_TRAN_CONTINUE;
480
481    case TLS_ST_OK:
482        if (s->key_update != SSL_KEY_UPDATE_NONE) {
483            st->hand_state = TLS_ST_CW_KEY_UPDATE;
484            return WRITE_TRAN_CONTINUE;
485        }
486
487        /* Try to read from the server instead */
488        return WRITE_TRAN_FINISHED;
489    }
490}
491
492/*
493 * ossl_statem_client_write_transition() works out what handshake state to
494 * move to next when the client is writing messages to be sent to the server.
495 */
496WRITE_TRAN ossl_statem_client_write_transition(SSL *s)
497{
498    OSSL_STATEM *st = &s->statem;
499
500    /*
501     * Note that immediately before/after a ClientHello we don't know what
502     * version we are going to negotiate yet, so we don't take this branch until
503     * later
504     */
505    if (SSL_IS_TLS13(s))
506        return ossl_statem_client13_write_transition(s);
507
508    switch (st->hand_state) {
509    default:
510        /* Shouldn't happen */
511        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
512        return WRITE_TRAN_ERROR;
513
514    case TLS_ST_OK:
515        if (!s->renegotiate) {
516            /*
517             * We haven't requested a renegotiation ourselves so we must have
518             * received a message from the server. Better read it.
519             */
520            return WRITE_TRAN_FINISHED;
521        }
522        /* Renegotiation */
523        /* fall thru */
524    case TLS_ST_BEFORE:
525        st->hand_state = TLS_ST_CW_CLNT_HELLO;
526        return WRITE_TRAN_CONTINUE;
527
528    case TLS_ST_CW_CLNT_HELLO:
529        if (s->early_data_state == SSL_EARLY_DATA_CONNECTING) {
530            /*
531             * We are assuming this is a TLSv1.3 connection, although we haven't
532             * actually selected a version yet.
533             */
534            if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0)
535                st->hand_state = TLS_ST_CW_CHANGE;
536            else
537                st->hand_state = TLS_ST_EARLY_DATA;
538            return WRITE_TRAN_CONTINUE;
539        }
540        /*
541         * No transition at the end of writing because we don't know what
542         * we will be sent
543         */
544        return WRITE_TRAN_FINISHED;
545
546    case TLS_ST_CR_SRVR_HELLO:
547        /*
548         * We only get here in TLSv1.3. We just received an HRR, so issue a
549         * CCS unless middlebox compat mode is off, or we already issued one
550         * because we did early data.
551         */
552        if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
553                && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING)
554            st->hand_state = TLS_ST_CW_CHANGE;
555        else
556            st->hand_state = TLS_ST_CW_CLNT_HELLO;
557        return WRITE_TRAN_CONTINUE;
558
559    case TLS_ST_EARLY_DATA:
560        return WRITE_TRAN_FINISHED;
561
562    case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
563        st->hand_state = TLS_ST_CW_CLNT_HELLO;
564        return WRITE_TRAN_CONTINUE;
565
566    case TLS_ST_CR_SRVR_DONE:
567        if (s->s3.tmp.cert_req)
568            st->hand_state = TLS_ST_CW_CERT;
569        else
570            st->hand_state = TLS_ST_CW_KEY_EXCH;
571        return WRITE_TRAN_CONTINUE;
572
573    case TLS_ST_CW_CERT:
574        st->hand_state = TLS_ST_CW_KEY_EXCH;
575        return WRITE_TRAN_CONTINUE;
576
577    case TLS_ST_CW_KEY_EXCH:
578        /*
579         * For TLS, cert_req is set to 2, so a cert chain of nothing is
580         * sent, but no verify packet is sent
581         */
582        /*
583         * XXX: For now, we do not support client authentication in ECDH
584         * cipher suites with ECDH (rather than ECDSA) certificates. We
585         * need to skip the certificate verify message when client's
586         * ECDH public key is sent inside the client certificate.
587         */
588        if (s->s3.tmp.cert_req == 1) {
589            st->hand_state = TLS_ST_CW_CERT_VRFY;
590        } else {
591            st->hand_state = TLS_ST_CW_CHANGE;
592        }
593        if (s->s3.flags & TLS1_FLAGS_SKIP_CERT_VERIFY) {
594            st->hand_state = TLS_ST_CW_CHANGE;
595        }
596        return WRITE_TRAN_CONTINUE;
597
598    case TLS_ST_CW_CERT_VRFY:
599        st->hand_state = TLS_ST_CW_CHANGE;
600        return WRITE_TRAN_CONTINUE;
601
602    case TLS_ST_CW_CHANGE:
603        if (s->hello_retry_request == SSL_HRR_PENDING) {
604            st->hand_state = TLS_ST_CW_CLNT_HELLO;
605        } else if (s->early_data_state == SSL_EARLY_DATA_CONNECTING) {
606            st->hand_state = TLS_ST_EARLY_DATA;
607        } else {
608#if defined(OPENSSL_NO_NEXTPROTONEG)
609            st->hand_state = TLS_ST_CW_FINISHED;
610#else
611            if (!SSL_IS_DTLS(s) && s->s3.npn_seen)
612                st->hand_state = TLS_ST_CW_NEXT_PROTO;
613            else
614                st->hand_state = TLS_ST_CW_FINISHED;
615#endif
616        }
617        return WRITE_TRAN_CONTINUE;
618
619#if !defined(OPENSSL_NO_NEXTPROTONEG)
620    case TLS_ST_CW_NEXT_PROTO:
621        st->hand_state = TLS_ST_CW_FINISHED;
622        return WRITE_TRAN_CONTINUE;
623#endif
624
625    case TLS_ST_CW_FINISHED:
626        if (s->hit) {
627            st->hand_state = TLS_ST_OK;
628            return WRITE_TRAN_CONTINUE;
629        } else {
630            return WRITE_TRAN_FINISHED;
631        }
632
633    case TLS_ST_CR_FINISHED:
634        if (s->hit) {
635            st->hand_state = TLS_ST_CW_CHANGE;
636            return WRITE_TRAN_CONTINUE;
637        } else {
638            st->hand_state = TLS_ST_OK;
639            return WRITE_TRAN_CONTINUE;
640        }
641
642    case TLS_ST_CR_HELLO_REQ:
643        /*
644         * If we can renegotiate now then do so, otherwise wait for a more
645         * convenient time.
646         */
647        if (ssl3_renegotiate_check(s, 1)) {
648            if (!tls_setup_handshake(s)) {
649                /* SSLfatal() already called */
650                return WRITE_TRAN_ERROR;
651            }
652            st->hand_state = TLS_ST_CW_CLNT_HELLO;
653            return WRITE_TRAN_CONTINUE;
654        }
655        st->hand_state = TLS_ST_OK;
656        return WRITE_TRAN_CONTINUE;
657    }
658}
659
660/*
661 * Perform any pre work that needs to be done prior to sending a message from
662 * the client to the server.
663 */
664WORK_STATE ossl_statem_client_pre_work(SSL *s, WORK_STATE wst)
665{
666    OSSL_STATEM *st = &s->statem;
667
668    switch (st->hand_state) {
669    default:
670        /* No pre work to be done */
671        break;
672
673    case TLS_ST_CW_CLNT_HELLO:
674        s->shutdown = 0;
675        if (SSL_IS_DTLS(s)) {
676            /* every DTLS ClientHello resets Finished MAC */
677            if (!ssl3_init_finished_mac(s)) {
678                /* SSLfatal() already called */
679                return WORK_ERROR;
680            }
681        }
682        break;
683
684    case TLS_ST_CW_CHANGE:
685        if (SSL_IS_DTLS(s)) {
686            if (s->hit) {
687                /*
688                 * We're into the last flight so we don't retransmit these
689                 * messages unless we need to.
690                 */
691                st->use_timer = 0;
692            }
693#ifndef OPENSSL_NO_SCTP
694            if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
695                /* Calls SSLfatal() as required */
696                return dtls_wait_for_dry(s);
697            }
698#endif
699        }
700        break;
701
702    case TLS_ST_PENDING_EARLY_DATA_END:
703        /*
704         * If we've been called by SSL_do_handshake()/SSL_write(), or we did not
705         * attempt to write early data before calling SSL_read() then we press
706         * on with the handshake. Otherwise we pause here.
707         */
708        if (s->early_data_state == SSL_EARLY_DATA_FINISHED_WRITING
709                || s->early_data_state == SSL_EARLY_DATA_NONE)
710            return WORK_FINISHED_CONTINUE;
711        /* Fall through */
712
713    case TLS_ST_EARLY_DATA:
714        return tls_finish_handshake(s, wst, 0, 1);
715
716    case TLS_ST_OK:
717        /* Calls SSLfatal() as required */
718        return tls_finish_handshake(s, wst, 1, 1);
719    }
720
721    return WORK_FINISHED_CONTINUE;
722}
723
724/*
725 * Perform any work that needs to be done after sending a message from the
726 * client to the server.
727 */
728WORK_STATE ossl_statem_client_post_work(SSL *s, WORK_STATE wst)
729{
730    OSSL_STATEM *st = &s->statem;
731
732    s->init_num = 0;
733
734    switch (st->hand_state) {
735    default:
736        /* No post work to be done */
737        break;
738
739    case TLS_ST_CW_CLNT_HELLO:
740        if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
741                && s->max_early_data > 0) {
742            /*
743             * We haven't selected TLSv1.3 yet so we don't call the change
744             * cipher state function associated with the SSL_METHOD. Instead
745             * we call tls13_change_cipher_state() directly.
746             */
747            if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) == 0) {
748                if (!tls13_change_cipher_state(s,
749                            SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
750                    /* SSLfatal() already called */
751                    return WORK_ERROR;
752                }
753            }
754            /* else we're in compat mode so we delay flushing until after CCS */
755        } else if (!statem_flush(s)) {
756            return WORK_MORE_A;
757        }
758
759        if (SSL_IS_DTLS(s)) {
760            /* Treat the next message as the first packet */
761            s->first_packet = 1;
762        }
763        break;
764
765    case TLS_ST_CW_END_OF_EARLY_DATA:
766        /*
767         * We set the enc_write_ctx back to NULL because we may end up writing
768         * in cleartext again if we get a HelloRetryRequest from the server.
769         */
770        EVP_CIPHER_CTX_free(s->enc_write_ctx);
771        s->enc_write_ctx = NULL;
772        break;
773
774    case TLS_ST_CW_KEY_EXCH:
775        if (tls_client_key_exchange_post_work(s) == 0) {
776            /* SSLfatal() already called */
777            return WORK_ERROR;
778        }
779        break;
780
781    case TLS_ST_CW_CHANGE:
782        if (SSL_IS_TLS13(s) || s->hello_retry_request == SSL_HRR_PENDING)
783            break;
784        if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
785                    && s->max_early_data > 0) {
786            /*
787             * We haven't selected TLSv1.3 yet so we don't call the change
788             * cipher state function associated with the SSL_METHOD. Instead
789             * we call tls13_change_cipher_state() directly.
790             */
791            if (!tls13_change_cipher_state(s,
792                        SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_CLIENT_WRITE))
793                return WORK_ERROR;
794            break;
795        }
796        s->session->cipher = s->s3.tmp.new_cipher;
797#ifdef OPENSSL_NO_COMP
798        s->session->compress_meth = 0;
799#else
800        if (s->s3.tmp.new_compression == NULL)
801            s->session->compress_meth = 0;
802        else
803            s->session->compress_meth = s->s3.tmp.new_compression->id;
804#endif
805        if (!s->method->ssl3_enc->setup_key_block(s)) {
806            /* SSLfatal() already called */
807            return WORK_ERROR;
808        }
809
810        if (!s->method->ssl3_enc->change_cipher_state(s,
811                                          SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
812            /* SSLfatal() already called */
813            return WORK_ERROR;
814        }
815
816        if (SSL_IS_DTLS(s)) {
817#ifndef OPENSSL_NO_SCTP
818            if (s->hit) {
819                /*
820                 * Change to new shared key of SCTP-Auth, will be ignored if
821                 * no SCTP used.
822                 */
823                BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
824                         0, NULL);
825            }
826#endif
827
828            dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
829        }
830        break;
831
832    case TLS_ST_CW_FINISHED:
833#ifndef OPENSSL_NO_SCTP
834        if (wst == WORK_MORE_A && SSL_IS_DTLS(s) && s->hit == 0) {
835            /*
836             * Change to new shared key of SCTP-Auth, will be ignored if
837             * no SCTP used.
838             */
839            BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
840                     0, NULL);
841        }
842#endif
843        if (statem_flush(s) != 1)
844            return WORK_MORE_B;
845
846        if (SSL_IS_TLS13(s)) {
847            if (!tls13_save_handshake_digest_for_pha(s)) {
848                /* SSLfatal() already called */
849                return WORK_ERROR;
850            }
851            if (s->post_handshake_auth != SSL_PHA_REQUESTED) {
852                if (!s->method->ssl3_enc->change_cipher_state(s,
853                        SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
854                    /* SSLfatal() already called */
855                    return WORK_ERROR;
856                }
857            }
858        }
859        break;
860
861    case TLS_ST_CW_KEY_UPDATE:
862        if (statem_flush(s) != 1)
863            return WORK_MORE_A;
864        if (!tls13_update_key(s, 1)) {
865            /* SSLfatal() already called */
866            return WORK_ERROR;
867        }
868        break;
869    }
870
871    return WORK_FINISHED_CONTINUE;
872}
873
874/*
875 * Get the message construction function and message type for sending from the
876 * client
877 *
878 * Valid return values are:
879 *   1: Success
880 *   0: Error
881 */
882int ossl_statem_client_construct_message(SSL *s, WPACKET *pkt,
883                                         confunc_f *confunc, int *mt)
884{
885    OSSL_STATEM *st = &s->statem;
886
887    switch (st->hand_state) {
888    default:
889        /* Shouldn't happen */
890        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_STATE);
891        return 0;
892
893    case TLS_ST_CW_CHANGE:
894        if (SSL_IS_DTLS(s))
895            *confunc = dtls_construct_change_cipher_spec;
896        else
897            *confunc = tls_construct_change_cipher_spec;
898        *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
899        break;
900
901    case TLS_ST_CW_CLNT_HELLO:
902        *confunc = tls_construct_client_hello;
903        *mt = SSL3_MT_CLIENT_HELLO;
904        break;
905
906    case TLS_ST_CW_END_OF_EARLY_DATA:
907        *confunc = tls_construct_end_of_early_data;
908        *mt = SSL3_MT_END_OF_EARLY_DATA;
909        break;
910
911    case TLS_ST_PENDING_EARLY_DATA_END:
912        *confunc = NULL;
913        *mt = SSL3_MT_DUMMY;
914        break;
915
916    case TLS_ST_CW_CERT:
917        *confunc = tls_construct_client_certificate;
918        *mt = SSL3_MT_CERTIFICATE;
919        break;
920
921    case TLS_ST_CW_KEY_EXCH:
922        *confunc = tls_construct_client_key_exchange;
923        *mt = SSL3_MT_CLIENT_KEY_EXCHANGE;
924        break;
925
926    case TLS_ST_CW_CERT_VRFY:
927        *confunc = tls_construct_cert_verify;
928        *mt = SSL3_MT_CERTIFICATE_VERIFY;
929        break;
930
931#if !defined(OPENSSL_NO_NEXTPROTONEG)
932    case TLS_ST_CW_NEXT_PROTO:
933        *confunc = tls_construct_next_proto;
934        *mt = SSL3_MT_NEXT_PROTO;
935        break;
936#endif
937    case TLS_ST_CW_FINISHED:
938        *confunc = tls_construct_finished;
939        *mt = SSL3_MT_FINISHED;
940        break;
941
942    case TLS_ST_CW_KEY_UPDATE:
943        *confunc = tls_construct_key_update;
944        *mt = SSL3_MT_KEY_UPDATE;
945        break;
946    }
947
948    return 1;
949}
950
951/*
952 * Returns the maximum allowed length for the current message that we are
953 * reading. Excludes the message header.
954 */
955size_t ossl_statem_client_max_message_size(SSL *s)
956{
957    OSSL_STATEM *st = &s->statem;
958
959    switch (st->hand_state) {
960    default:
961        /* Shouldn't happen */
962        return 0;
963
964    case TLS_ST_CR_SRVR_HELLO:
965        return SERVER_HELLO_MAX_LENGTH;
966
967    case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
968        return HELLO_VERIFY_REQUEST_MAX_LENGTH;
969
970    case TLS_ST_CR_CERT:
971        return s->max_cert_list;
972
973    case TLS_ST_CR_CERT_VRFY:
974        return SSL3_RT_MAX_PLAIN_LENGTH;
975
976    case TLS_ST_CR_CERT_STATUS:
977        return SSL3_RT_MAX_PLAIN_LENGTH;
978
979    case TLS_ST_CR_KEY_EXCH:
980        return SERVER_KEY_EXCH_MAX_LENGTH;
981
982    case TLS_ST_CR_CERT_REQ:
983        /*
984         * Set to s->max_cert_list for compatibility with previous releases. In
985         * practice these messages can get quite long if servers are configured
986         * to provide a long list of acceptable CAs
987         */
988        return s->max_cert_list;
989
990    case TLS_ST_CR_SRVR_DONE:
991        return SERVER_HELLO_DONE_MAX_LENGTH;
992
993    case TLS_ST_CR_CHANGE:
994        if (s->version == DTLS1_BAD_VER)
995            return 3;
996        return CCS_MAX_LENGTH;
997
998    case TLS_ST_CR_SESSION_TICKET:
999        return (SSL_IS_TLS13(s)) ? SESSION_TICKET_MAX_LENGTH_TLS13
1000                                 : SESSION_TICKET_MAX_LENGTH_TLS12;
1001
1002    case TLS_ST_CR_FINISHED:
1003        return FINISHED_MAX_LENGTH;
1004
1005    case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
1006        return ENCRYPTED_EXTENSIONS_MAX_LENGTH;
1007
1008    case TLS_ST_CR_KEY_UPDATE:
1009        return KEY_UPDATE_MAX_LENGTH;
1010    }
1011}
1012
1013/*
1014 * Process a message that the client has received from the server.
1015 */
1016MSG_PROCESS_RETURN ossl_statem_client_process_message(SSL *s, PACKET *pkt)
1017{
1018    OSSL_STATEM *st = &s->statem;
1019
1020    switch (st->hand_state) {
1021    default:
1022        /* Shouldn't happen */
1023        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1024        return MSG_PROCESS_ERROR;
1025
1026    case TLS_ST_CR_SRVR_HELLO:
1027        return tls_process_server_hello(s, pkt);
1028
1029    case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
1030        return dtls_process_hello_verify(s, pkt);
1031
1032    case TLS_ST_CR_CERT:
1033        return tls_process_server_certificate(s, pkt);
1034
1035    case TLS_ST_CR_CERT_VRFY:
1036        return tls_process_cert_verify(s, pkt);
1037
1038    case TLS_ST_CR_CERT_STATUS:
1039        return tls_process_cert_status(s, pkt);
1040
1041    case TLS_ST_CR_KEY_EXCH:
1042        return tls_process_key_exchange(s, pkt);
1043
1044    case TLS_ST_CR_CERT_REQ:
1045        return tls_process_certificate_request(s, pkt);
1046
1047    case TLS_ST_CR_SRVR_DONE:
1048        return tls_process_server_done(s, pkt);
1049
1050    case TLS_ST_CR_CHANGE:
1051        return tls_process_change_cipher_spec(s, pkt);
1052
1053    case TLS_ST_CR_SESSION_TICKET:
1054        return tls_process_new_session_ticket(s, pkt);
1055
1056    case TLS_ST_CR_FINISHED:
1057        return tls_process_finished(s, pkt);
1058
1059    case TLS_ST_CR_HELLO_REQ:
1060        return tls_process_hello_req(s, pkt);
1061
1062    case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
1063        return tls_process_encrypted_extensions(s, pkt);
1064
1065    case TLS_ST_CR_KEY_UPDATE:
1066        return tls_process_key_update(s, pkt);
1067    }
1068}
1069
1070/*
1071 * Perform any further processing required following the receipt of a message
1072 * from the server
1073 */
1074WORK_STATE ossl_statem_client_post_process_message(SSL *s, WORK_STATE wst)
1075{
1076    OSSL_STATEM *st = &s->statem;
1077
1078    switch (st->hand_state) {
1079    default:
1080        /* Shouldn't happen */
1081        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1082        return WORK_ERROR;
1083
1084    case TLS_ST_CR_CERT:
1085        return tls_post_process_server_certificate(s, wst);
1086
1087    case TLS_ST_CR_CERT_VRFY:
1088    case TLS_ST_CR_CERT_REQ:
1089        return tls_prepare_client_certificate(s, wst);
1090    }
1091}
1092
1093int tls_construct_client_hello(SSL *s, WPACKET *pkt)
1094{
1095    unsigned char *p;
1096    size_t sess_id_len;
1097    int i, protverr;
1098#ifndef OPENSSL_NO_COMP
1099    SSL_COMP *comp;
1100#endif
1101    SSL_SESSION *sess = s->session;
1102    unsigned char *session_id;
1103
1104    /* Work out what SSL/TLS/DTLS version to use */
1105    protverr = ssl_set_client_hello_version(s);
1106    if (protverr != 0) {
1107        SSLfatal(s, SSL_AD_INTERNAL_ERROR, protverr);
1108        return 0;
1109    }
1110
1111    if (sess == NULL
1112            || !ssl_version_supported(s, sess->ssl_version, NULL)
1113            || !SSL_SESSION_is_resumable(sess)) {
1114        if (s->hello_retry_request == SSL_HRR_NONE
1115                && !ssl_get_new_session(s, 0)) {
1116            /* SSLfatal() already called */
1117            return 0;
1118        }
1119    }
1120    /* else use the pre-loaded session */
1121
1122    p = s->s3.client_random;
1123
1124    /*
1125     * for DTLS if client_random is initialized, reuse it, we are
1126     * required to use same upon reply to HelloVerify
1127     */
1128    if (SSL_IS_DTLS(s)) {
1129        size_t idx;
1130        i = 1;
1131        for (idx = 0; idx < sizeof(s->s3.client_random); idx++) {
1132            if (p[idx]) {
1133                i = 0;
1134                break;
1135            }
1136        }
1137    } else {
1138        i = (s->hello_retry_request == SSL_HRR_NONE);
1139    }
1140
1141    if (i && ssl_fill_hello_random(s, 0, p, sizeof(s->s3.client_random),
1142                                   DOWNGRADE_NONE) <= 0) {
1143        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1144        return 0;
1145    }
1146
1147    /*-
1148     * version indicates the negotiated version: for example from
1149     * an SSLv2/v3 compatible client hello). The client_version
1150     * field is the maximum version we permit and it is also
1151     * used in RSA encrypted premaster secrets. Some servers can
1152     * choke if we initially report a higher version then
1153     * renegotiate to a lower one in the premaster secret. This
1154     * didn't happen with TLS 1.0 as most servers supported it
1155     * but it can with TLS 1.1 or later if the server only supports
1156     * 1.0.
1157     *
1158     * Possible scenario with previous logic:
1159     *      1. Client hello indicates TLS 1.2
1160     *      2. Server hello says TLS 1.0
1161     *      3. RSA encrypted premaster secret uses 1.2.
1162     *      4. Handshake proceeds using TLS 1.0.
1163     *      5. Server sends hello request to renegotiate.
1164     *      6. Client hello indicates TLS v1.0 as we now
1165     *         know that is maximum server supports.
1166     *      7. Server chokes on RSA encrypted premaster secret
1167     *         containing version 1.0.
1168     *
1169     * For interoperability it should be OK to always use the
1170     * maximum version we support in client hello and then rely
1171     * on the checking of version to ensure the servers isn't
1172     * being inconsistent: for example initially negotiating with
1173     * TLS 1.0 and renegotiating with TLS 1.2. We do this by using
1174     * client_version in client hello and not resetting it to
1175     * the negotiated version.
1176     *
1177     * For TLS 1.3 we always set the ClientHello version to 1.2 and rely on the
1178     * supported_versions extension for the real supported versions.
1179     */
1180    if (!WPACKET_put_bytes_u16(pkt, s->client_version)
1181            || !WPACKET_memcpy(pkt, s->s3.client_random, SSL3_RANDOM_SIZE)) {
1182        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1183        return 0;
1184    }
1185
1186    /* Session ID */
1187    session_id = s->session->session_id;
1188    if (s->new_session || s->session->ssl_version == TLS1_3_VERSION) {
1189        if (s->version == TLS1_3_VERSION
1190                && (s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0) {
1191            sess_id_len = sizeof(s->tmp_session_id);
1192            s->tmp_session_id_len = sess_id_len;
1193            session_id = s->tmp_session_id;
1194            if (s->hello_retry_request == SSL_HRR_NONE
1195                    && RAND_bytes_ex(s->ctx->libctx, s->tmp_session_id,
1196                                     sess_id_len, 0) <= 0) {
1197                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1198                return 0;
1199            }
1200        } else {
1201            sess_id_len = 0;
1202        }
1203    } else {
1204        assert(s->session->session_id_length <= sizeof(s->session->session_id));
1205        sess_id_len = s->session->session_id_length;
1206        if (s->version == TLS1_3_VERSION) {
1207            s->tmp_session_id_len = sess_id_len;
1208            memcpy(s->tmp_session_id, s->session->session_id, sess_id_len);
1209        }
1210    }
1211    if (!WPACKET_start_sub_packet_u8(pkt)
1212            || (sess_id_len != 0 && !WPACKET_memcpy(pkt, session_id,
1213                                                    sess_id_len))
1214            || !WPACKET_close(pkt)) {
1215        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1216        return 0;
1217    }
1218
1219    /* cookie stuff for DTLS */
1220    if (SSL_IS_DTLS(s)) {
1221        if (s->d1->cookie_len > sizeof(s->d1->cookie)
1222                || !WPACKET_sub_memcpy_u8(pkt, s->d1->cookie,
1223                                          s->d1->cookie_len)) {
1224            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1225            return 0;
1226        }
1227    }
1228
1229    /* Ciphers supported */
1230    if (!WPACKET_start_sub_packet_u16(pkt)) {
1231        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1232        return 0;
1233    }
1234
1235    if (!ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s), pkt)) {
1236        /* SSLfatal() already called */
1237        return 0;
1238    }
1239    if (!WPACKET_close(pkt)) {
1240        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1241        return 0;
1242    }
1243
1244    /* COMPRESSION */
1245    if (!WPACKET_start_sub_packet_u8(pkt)) {
1246        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1247        return 0;
1248    }
1249#ifndef OPENSSL_NO_COMP
1250    if (ssl_allow_compression(s)
1251            && s->ctx->comp_methods
1252            && (SSL_IS_DTLS(s) || s->s3.tmp.max_ver < TLS1_3_VERSION)) {
1253        int compnum = sk_SSL_COMP_num(s->ctx->comp_methods);
1254        for (i = 0; i < compnum; i++) {
1255            comp = sk_SSL_COMP_value(s->ctx->comp_methods, i);
1256            if (!WPACKET_put_bytes_u8(pkt, comp->id)) {
1257                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1258                return 0;
1259            }
1260        }
1261    }
1262#endif
1263    /* Add the NULL method */
1264    if (!WPACKET_put_bytes_u8(pkt, 0) || !WPACKET_close(pkt)) {
1265        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1266        return 0;
1267    }
1268
1269    /* TLS extensions */
1270    if (!tls_construct_extensions(s, pkt, SSL_EXT_CLIENT_HELLO, NULL, 0)) {
1271        /* SSLfatal() already called */
1272        return 0;
1273    }
1274
1275    return 1;
1276}
1277
1278MSG_PROCESS_RETURN dtls_process_hello_verify(SSL *s, PACKET *pkt)
1279{
1280    size_t cookie_len;
1281    PACKET cookiepkt;
1282
1283    if (!PACKET_forward(pkt, 2)
1284        || !PACKET_get_length_prefixed_1(pkt, &cookiepkt)) {
1285        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1286        return MSG_PROCESS_ERROR;
1287    }
1288
1289    cookie_len = PACKET_remaining(&cookiepkt);
1290    if (cookie_len > sizeof(s->d1->cookie)) {
1291        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_LENGTH_TOO_LONG);
1292        return MSG_PROCESS_ERROR;
1293    }
1294
1295    if (!PACKET_copy_bytes(&cookiepkt, s->d1->cookie, cookie_len)) {
1296        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1297        return MSG_PROCESS_ERROR;
1298    }
1299    s->d1->cookie_len = cookie_len;
1300
1301    return MSG_PROCESS_FINISHED_READING;
1302}
1303
1304static int set_client_ciphersuite(SSL *s, const unsigned char *cipherchars)
1305{
1306    STACK_OF(SSL_CIPHER) *sk;
1307    const SSL_CIPHER *c;
1308    int i;
1309
1310    c = ssl_get_cipher_by_char(s, cipherchars, 0);
1311    if (c == NULL) {
1312        /* unknown cipher */
1313        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_UNKNOWN_CIPHER_RETURNED);
1314        return 0;
1315    }
1316    /*
1317     * If it is a disabled cipher we either didn't send it in client hello,
1318     * or it's not allowed for the selected protocol. So we return an error.
1319     */
1320    if (ssl_cipher_disabled(s, c, SSL_SECOP_CIPHER_CHECK, 1)) {
1321        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CIPHER_RETURNED);
1322        return 0;
1323    }
1324
1325    sk = ssl_get_ciphers_by_id(s);
1326    i = sk_SSL_CIPHER_find(sk, c);
1327    if (i < 0) {
1328        /* we did not say we would use this cipher */
1329        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CIPHER_RETURNED);
1330        return 0;
1331    }
1332
1333    if (SSL_IS_TLS13(s) && s->s3.tmp.new_cipher != NULL
1334            && s->s3.tmp.new_cipher->id != c->id) {
1335        /* ServerHello selected a different ciphersuite to that in the HRR */
1336        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CIPHER_RETURNED);
1337        return 0;
1338    }
1339
1340    /*
1341     * Depending on the session caching (internal/external), the cipher
1342     * and/or cipher_id values may not be set. Make sure that cipher_id is
1343     * set and use it for comparison.
1344     */
1345    if (s->session->cipher != NULL)
1346        s->session->cipher_id = s->session->cipher->id;
1347    if (s->hit && (s->session->cipher_id != c->id)) {
1348        if (SSL_IS_TLS13(s)) {
1349            const EVP_MD *md = ssl_md(s->ctx, c->algorithm2);
1350
1351            /*
1352             * In TLSv1.3 it is valid for the server to select a different
1353             * ciphersuite as long as the hash is the same.
1354             */
1355            if (md == NULL
1356                    || md != ssl_md(s->ctx, s->session->cipher->algorithm2)) {
1357                SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1358                         SSL_R_CIPHERSUITE_DIGEST_HAS_CHANGED);
1359                return 0;
1360            }
1361        } else {
1362            /*
1363             * Prior to TLSv1.3 resuming a session always meant using the same
1364             * ciphersuite.
1365             */
1366            SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1367                     SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED);
1368            return 0;
1369        }
1370    }
1371    s->s3.tmp.new_cipher = c;
1372
1373    return 1;
1374}
1375
1376MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
1377{
1378    PACKET session_id, extpkt;
1379    size_t session_id_len;
1380    const unsigned char *cipherchars;
1381    int hrr = 0;
1382    unsigned int compression;
1383    unsigned int sversion;
1384    unsigned int context;
1385    RAW_EXTENSION *extensions = NULL;
1386#ifndef OPENSSL_NO_COMP
1387    SSL_COMP *comp;
1388#endif
1389
1390    if (!PACKET_get_net_2(pkt, &sversion)) {
1391        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1392        goto err;
1393    }
1394
1395    /* load the server random */
1396    if (s->version == TLS1_3_VERSION
1397            && sversion == TLS1_2_VERSION
1398            && PACKET_remaining(pkt) >= SSL3_RANDOM_SIZE
1399            && memcmp(hrrrandom, PACKET_data(pkt), SSL3_RANDOM_SIZE) == 0) {
1400        if (s->hello_retry_request != SSL_HRR_NONE) {
1401            SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
1402            goto err;
1403        }
1404        s->hello_retry_request = SSL_HRR_PENDING;
1405        hrr = 1;
1406        if (!PACKET_forward(pkt, SSL3_RANDOM_SIZE)) {
1407            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1408            goto err;
1409        }
1410    } else {
1411        if (!PACKET_copy_bytes(pkt, s->s3.server_random, SSL3_RANDOM_SIZE)) {
1412            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1413            goto err;
1414        }
1415    }
1416
1417    /* Get the session-id. */
1418    if (!PACKET_get_length_prefixed_1(pkt, &session_id)) {
1419        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1420        goto err;
1421    }
1422    session_id_len = PACKET_remaining(&session_id);
1423    if (session_id_len > sizeof(s->session->session_id)
1424        || session_id_len > SSL3_SESSION_ID_SIZE) {
1425        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_SSL3_SESSION_ID_TOO_LONG);
1426        goto err;
1427    }
1428
1429    if (!PACKET_get_bytes(pkt, &cipherchars, TLS_CIPHER_LEN)) {
1430        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1431        goto err;
1432    }
1433
1434    if (!PACKET_get_1(pkt, &compression)) {
1435        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1436        goto err;
1437    }
1438
1439    /* TLS extensions */
1440    if (PACKET_remaining(pkt) == 0 && !hrr) {
1441        PACKET_null_init(&extpkt);
1442    } else if (!PACKET_as_length_prefixed_2(pkt, &extpkt)
1443               || PACKET_remaining(pkt) != 0) {
1444        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
1445        goto err;
1446    }
1447
1448    if (!hrr) {
1449        if (!tls_collect_extensions(s, &extpkt,
1450                                    SSL_EXT_TLS1_2_SERVER_HELLO
1451                                    | SSL_EXT_TLS1_3_SERVER_HELLO,
1452                                    &extensions, NULL, 1)) {
1453            /* SSLfatal() already called */
1454            goto err;
1455        }
1456
1457        if (!ssl_choose_client_version(s, sversion, extensions)) {
1458            /* SSLfatal() already called */
1459            goto err;
1460        }
1461    }
1462
1463    if (SSL_IS_TLS13(s) || hrr) {
1464        if (compression != 0) {
1465            SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1466                     SSL_R_INVALID_COMPRESSION_ALGORITHM);
1467            goto err;
1468        }
1469
1470        if (session_id_len != s->tmp_session_id_len
1471                || memcmp(PACKET_data(&session_id), s->tmp_session_id,
1472                          session_id_len) != 0) {
1473            SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_INVALID_SESSION_ID);
1474            goto err;
1475        }
1476    }
1477
1478    if (hrr) {
1479        if (!set_client_ciphersuite(s, cipherchars)) {
1480            /* SSLfatal() already called */
1481            goto err;
1482        }
1483
1484        return tls_process_as_hello_retry_request(s, &extpkt);
1485    }
1486
1487    /*
1488     * Now we have chosen the version we need to check again that the extensions
1489     * are appropriate for this version.
1490     */
1491    context = SSL_IS_TLS13(s) ? SSL_EXT_TLS1_3_SERVER_HELLO
1492                              : SSL_EXT_TLS1_2_SERVER_HELLO;
1493    if (!tls_validate_all_contexts(s, context, extensions)) {
1494        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_EXTENSION);
1495        goto err;
1496    }
1497
1498    s->hit = 0;
1499
1500    if (SSL_IS_TLS13(s)) {
1501        /*
1502         * In TLSv1.3 a ServerHello message signals a key change so the end of
1503         * the message must be on a record boundary.
1504         */
1505        if (RECORD_LAYER_processed_read_pending(&s->rlayer)) {
1506            SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
1507                     SSL_R_NOT_ON_RECORD_BOUNDARY);
1508            goto err;
1509        }
1510
1511        /* This will set s->hit if we are resuming */
1512        if (!tls_parse_extension(s, TLSEXT_IDX_psk,
1513                                 SSL_EXT_TLS1_3_SERVER_HELLO,
1514                                 extensions, NULL, 0)) {
1515            /* SSLfatal() already called */
1516            goto err;
1517        }
1518    } else {
1519        /*
1520         * Check if we can resume the session based on external pre-shared
1521         * secret. EAP-FAST (RFC 4851) supports two types of session resumption.
1522         * Resumption based on server-side state works with session IDs.
1523         * Resumption based on pre-shared Protected Access Credentials (PACs)
1524         * works by overriding the SessionTicket extension at the application
1525         * layer, and does not send a session ID. (We do not know whether
1526         * EAP-FAST servers would honour the session ID.) Therefore, the session
1527         * ID alone is not a reliable indicator of session resumption, so we
1528         * first check if we can resume, and later peek at the next handshake
1529         * message to see if the server wants to resume.
1530         */
1531        if (s->version >= TLS1_VERSION
1532                && s->ext.session_secret_cb != NULL && s->session->ext.tick) {
1533            const SSL_CIPHER *pref_cipher = NULL;
1534            /*
1535             * s->session->master_key_length is a size_t, but this is an int for
1536             * backwards compat reasons
1537             */
1538            int master_key_length;
1539            master_key_length = sizeof(s->session->master_key);
1540            if (s->ext.session_secret_cb(s, s->session->master_key,
1541                                         &master_key_length,
1542                                         NULL, &pref_cipher,
1543                                         s->ext.session_secret_cb_arg)
1544                     && master_key_length > 0) {
1545                s->session->master_key_length = master_key_length;
1546                s->session->cipher = pref_cipher ?
1547                    pref_cipher : ssl_get_cipher_by_char(s, cipherchars, 0);
1548            } else {
1549                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1550                goto err;
1551            }
1552        }
1553
1554        if (session_id_len != 0
1555                && session_id_len == s->session->session_id_length
1556                && memcmp(PACKET_data(&session_id), s->session->session_id,
1557                          session_id_len) == 0)
1558            s->hit = 1;
1559    }
1560
1561    if (s->hit) {
1562        if (s->sid_ctx_length != s->session->sid_ctx_length
1563                || memcmp(s->session->sid_ctx, s->sid_ctx, s->sid_ctx_length)) {
1564            /* actually a client application bug */
1565            SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1566                     SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
1567            goto err;
1568        }
1569    } else {
1570        /*
1571         * If we were trying for session-id reuse but the server
1572         * didn't resume, make a new SSL_SESSION.
1573         * In the case of EAP-FAST and PAC, we do not send a session ID,
1574         * so the PAC-based session secret is always preserved. It'll be
1575         * overwritten if the server refuses resumption.
1576         */
1577        if (s->session->session_id_length > 0) {
1578            ssl_tsan_counter(s->session_ctx, &s->session_ctx->stats.sess_miss);
1579            if (!ssl_get_new_session(s, 0)) {
1580                /* SSLfatal() already called */
1581                goto err;
1582            }
1583        }
1584
1585        s->session->ssl_version = s->version;
1586        /*
1587         * In TLSv1.2 and below we save the session id we were sent so we can
1588         * resume it later. In TLSv1.3 the session id we were sent is just an
1589         * echo of what we originally sent in the ClientHello and should not be
1590         * used for resumption.
1591         */
1592        if (!SSL_IS_TLS13(s)) {
1593            s->session->session_id_length = session_id_len;
1594            /* session_id_len could be 0 */
1595            if (session_id_len > 0)
1596                memcpy(s->session->session_id, PACKET_data(&session_id),
1597                       session_id_len);
1598        }
1599    }
1600
1601    /* Session version and negotiated protocol version should match */
1602    if (s->version != s->session->ssl_version) {
1603        SSLfatal(s, SSL_AD_PROTOCOL_VERSION,
1604                 SSL_R_SSL_SESSION_VERSION_MISMATCH);
1605        goto err;
1606    }
1607    /*
1608     * Now that we know the version, update the check to see if it's an allowed
1609     * version.
1610     */
1611    s->s3.tmp.min_ver = s->version;
1612    s->s3.tmp.max_ver = s->version;
1613
1614    if (!set_client_ciphersuite(s, cipherchars)) {
1615        /* SSLfatal() already called */
1616        goto err;
1617    }
1618
1619#ifdef OPENSSL_NO_COMP
1620    if (compression != 0) {
1621        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1622                 SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
1623        goto err;
1624    }
1625    /*
1626     * If compression is disabled we'd better not try to resume a session
1627     * using compression.
1628     */
1629    if (s->session->compress_meth != 0) {
1630        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_INCONSISTENT_COMPRESSION);
1631        goto err;
1632    }
1633#else
1634    if (s->hit && compression != s->session->compress_meth) {
1635        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1636                 SSL_R_OLD_SESSION_COMPRESSION_ALGORITHM_NOT_RETURNED);
1637        goto err;
1638    }
1639    if (compression == 0)
1640        comp = NULL;
1641    else if (!ssl_allow_compression(s)) {
1642        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_COMPRESSION_DISABLED);
1643        goto err;
1644    } else {
1645        comp = ssl3_comp_find(s->ctx->comp_methods, compression);
1646    }
1647
1648    if (compression != 0 && comp == NULL) {
1649        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1650                 SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
1651        goto err;
1652    } else {
1653        s->s3.tmp.new_compression = comp;
1654    }
1655#endif
1656
1657    if (!tls_parse_all_extensions(s, context, extensions, NULL, 0, 1)) {
1658        /* SSLfatal() already called */
1659        goto err;
1660    }
1661
1662#ifndef OPENSSL_NO_SCTP
1663    if (SSL_IS_DTLS(s) && s->hit) {
1664        unsigned char sctpauthkey[64];
1665        char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
1666        size_t labellen;
1667
1668        /*
1669         * Add new shared key for SCTP-Auth, will be ignored if
1670         * no SCTP used.
1671         */
1672        memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
1673               sizeof(DTLS1_SCTP_AUTH_LABEL));
1674
1675        /* Don't include the terminating zero. */
1676        labellen = sizeof(labelbuffer) - 1;
1677        if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
1678            labellen += 1;
1679
1680        if (SSL_export_keying_material(s, sctpauthkey,
1681                                       sizeof(sctpauthkey),
1682                                       labelbuffer,
1683                                       labellen, NULL, 0, 0) <= 0) {
1684            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1685            goto err;
1686        }
1687
1688        BIO_ctrl(SSL_get_wbio(s),
1689                 BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
1690                 sizeof(sctpauthkey), sctpauthkey);
1691    }
1692#endif
1693
1694    /*
1695     * In TLSv1.3 we have some post-processing to change cipher state, otherwise
1696     * we're done with this message
1697     */
1698    if (SSL_IS_TLS13(s)
1699            && (!s->method->ssl3_enc->setup_key_block(s)
1700                || !s->method->ssl3_enc->change_cipher_state(s,
1701                    SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_READ))) {
1702        /* SSLfatal() already called */
1703        goto err;
1704    }
1705
1706    OPENSSL_free(extensions);
1707    return MSG_PROCESS_CONTINUE_READING;
1708 err:
1709    OPENSSL_free(extensions);
1710    return MSG_PROCESS_ERROR;
1711}
1712
1713static MSG_PROCESS_RETURN tls_process_as_hello_retry_request(SSL *s,
1714                                                             PACKET *extpkt)
1715{
1716    RAW_EXTENSION *extensions = NULL;
1717
1718    /*
1719     * If we were sending early_data then the enc_write_ctx is now invalid and
1720     * should not be used.
1721     */
1722    EVP_CIPHER_CTX_free(s->enc_write_ctx);
1723    s->enc_write_ctx = NULL;
1724
1725    if (!tls_collect_extensions(s, extpkt, SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST,
1726                                &extensions, NULL, 1)
1727            || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST,
1728                                         extensions, NULL, 0, 1)) {
1729        /* SSLfatal() already called */
1730        goto err;
1731    }
1732
1733    OPENSSL_free(extensions);
1734    extensions = NULL;
1735
1736    if (s->ext.tls13_cookie_len == 0 && s->s3.tmp.pkey != NULL) {
1737        /*
1738         * We didn't receive a cookie or a new key_share so the next
1739         * ClientHello will not change
1740         */
1741        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_NO_CHANGE_FOLLOWING_HRR);
1742        goto err;
1743    }
1744
1745    /*
1746     * Re-initialise the Transcript Hash. We're going to prepopulate it with
1747     * a synthetic message_hash in place of ClientHello1.
1748     */
1749    if (!create_synthetic_message_hash(s, NULL, 0, NULL, 0)) {
1750        /* SSLfatal() already called */
1751        goto err;
1752    }
1753
1754    /*
1755     * Add this message to the Transcript Hash. Normally this is done
1756     * automatically prior to the message processing stage. However due to the
1757     * need to create the synthetic message hash, we defer that step until now
1758     * for HRR messages.
1759     */
1760    if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
1761                                s->init_num + SSL3_HM_HEADER_LENGTH)) {
1762        /* SSLfatal() already called */
1763        goto err;
1764    }
1765
1766    return MSG_PROCESS_FINISHED_READING;
1767 err:
1768    OPENSSL_free(extensions);
1769    return MSG_PROCESS_ERROR;
1770}
1771
1772/* prepare server cert verification by setting s->session->peer_chain from pkt */
1773MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt)
1774{
1775    unsigned long cert_list_len, cert_len;
1776    X509 *x = NULL;
1777    const unsigned char *certstart, *certbytes;
1778    size_t chainidx;
1779    unsigned int context = 0;
1780
1781    if ((s->session->peer_chain = sk_X509_new_null()) == NULL) {
1782        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
1783        goto err;
1784    }
1785
1786    if ((SSL_IS_TLS13(s) && !PACKET_get_1(pkt, &context))
1787            || context != 0
1788            || !PACKET_get_net_3(pkt, &cert_list_len)
1789            || PACKET_remaining(pkt) != cert_list_len
1790            || PACKET_remaining(pkt) == 0) {
1791        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1792        goto err;
1793    }
1794    for (chainidx = 0; PACKET_remaining(pkt); chainidx++) {
1795        if (!PACKET_get_net_3(pkt, &cert_len)
1796            || !PACKET_get_bytes(pkt, &certbytes, cert_len)) {
1797            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_CERT_LENGTH_MISMATCH);
1798            goto err;
1799        }
1800
1801        certstart = certbytes;
1802        x = X509_new_ex(s->ctx->libctx, s->ctx->propq);
1803        if (x == NULL) {
1804            SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_MALLOC_FAILURE);
1805            ERR_raise(ERR_LIB_SSL, ERR_R_MALLOC_FAILURE);
1806            goto err;
1807        }
1808        if (d2i_X509(&x, (const unsigned char **)&certbytes,
1809                     cert_len) == NULL) {
1810            SSLfatal(s, SSL_AD_BAD_CERTIFICATE, ERR_R_ASN1_LIB);
1811            goto err;
1812        }
1813
1814        if (certbytes != (certstart + cert_len)) {
1815            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_CERT_LENGTH_MISMATCH);
1816            goto err;
1817        }
1818
1819        if (SSL_IS_TLS13(s)) {
1820            RAW_EXTENSION *rawexts = NULL;
1821            PACKET extensions;
1822
1823            if (!PACKET_get_length_prefixed_2(pkt, &extensions)) {
1824                SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
1825                goto err;
1826            }
1827            if (!tls_collect_extensions(s, &extensions,
1828                                        SSL_EXT_TLS1_3_CERTIFICATE, &rawexts,
1829                                        NULL, chainidx == 0)
1830                || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE,
1831                                             rawexts, x, chainidx,
1832                                             PACKET_remaining(pkt) == 0)) {
1833                OPENSSL_free(rawexts);
1834                /* SSLfatal already called */
1835                goto err;
1836            }
1837            OPENSSL_free(rawexts);
1838        }
1839
1840        if (!sk_X509_push(s->session->peer_chain, x)) {
1841            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
1842            goto err;
1843        }
1844        x = NULL;
1845    }
1846    return MSG_PROCESS_CONTINUE_PROCESSING;
1847
1848 err:
1849    X509_free(x);
1850    sk_X509_pop_free(s->session->peer_chain, X509_free);
1851    s->session->peer_chain = NULL;
1852    return MSG_PROCESS_ERROR;
1853}
1854
1855/*
1856 * Verify the s->session->peer_chain and check server cert type.
1857 * On success set s->session->peer and s->session->verify_result.
1858 * Else the peer certificate verification callback may request retry.
1859 */
1860WORK_STATE tls_post_process_server_certificate(SSL *s, WORK_STATE wst)
1861{
1862    X509 *x;
1863    EVP_PKEY *pkey = NULL;
1864    const SSL_CERT_LOOKUP *clu;
1865    size_t certidx;
1866    int i;
1867
1868    if (s->rwstate == SSL_RETRY_VERIFY)
1869        s->rwstate = SSL_NOTHING;
1870    i = ssl_verify_cert_chain(s, s->session->peer_chain);
1871    if (i > 0 && s->rwstate == SSL_RETRY_VERIFY) {
1872        return WORK_MORE_A;
1873    }
1874    /*
1875     * The documented interface is that SSL_VERIFY_PEER should be set in order
1876     * for client side verification of the server certificate to take place.
1877     * However, historically the code has only checked that *any* flag is set
1878     * to cause server verification to take place. Use of the other flags makes
1879     * no sense in client mode. An attempt to clean up the semantics was
1880     * reverted because at least one application *only* set
1881     * SSL_VERIFY_FAIL_IF_NO_PEER_CERT. Prior to the clean up this still caused
1882     * server verification to take place, after the clean up it silently did
1883     * nothing. SSL_CTX_set_verify()/SSL_set_verify() cannot validate the flags
1884     * sent to them because they are void functions. Therefore, we now use the
1885     * (less clean) historic behaviour of performing validation if any flag is
1886     * set. The *documented* interface remains the same.
1887     */
1888    if (s->verify_mode != SSL_VERIFY_NONE && i <= 0) {
1889        SSLfatal(s, ssl_x509err2alert(s->verify_result),
1890                 SSL_R_CERTIFICATE_VERIFY_FAILED);
1891        return WORK_ERROR;
1892    }
1893    ERR_clear_error();          /* but we keep s->verify_result */
1894
1895    /*
1896     * Inconsistency alert: cert_chain does include the peer's certificate,
1897     * which we don't include in statem_srvr.c
1898     */
1899    x = sk_X509_value(s->session->peer_chain, 0);
1900
1901    pkey = X509_get0_pubkey(x);
1902
1903    if (pkey == NULL || EVP_PKEY_missing_parameters(pkey)) {
1904        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1905                 SSL_R_UNABLE_TO_FIND_PUBLIC_KEY_PARAMETERS);
1906        return WORK_ERROR;
1907    }
1908
1909    if ((clu = ssl_cert_lookup_by_pkey(pkey, &certidx)) == NULL) {
1910        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
1911        return WORK_ERROR;
1912    }
1913    /*
1914     * Check certificate type is consistent with ciphersuite. For TLS 1.3
1915     * skip check since TLS 1.3 ciphersuites can be used with any certificate
1916     * type.
1917     */
1918    if (!SSL_IS_TLS13(s)) {
1919        if ((clu->amask & s->s3.tmp.new_cipher->algorithm_auth) == 0) {
1920            SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CERTIFICATE_TYPE);
1921            return WORK_ERROR;
1922        }
1923    }
1924
1925    X509_free(s->session->peer);
1926    X509_up_ref(x);
1927    s->session->peer = x;
1928    s->session->verify_result = s->verify_result;
1929
1930    /* Save the current hash state for when we receive the CertificateVerify */
1931    if (SSL_IS_TLS13(s)
1932            && !ssl_handshake_hash(s, s->cert_verify_hash,
1933                                   sizeof(s->cert_verify_hash),
1934                                   &s->cert_verify_hash_len)) {
1935        /* SSLfatal() already called */;
1936        return WORK_ERROR;
1937    }
1938    return WORK_FINISHED_CONTINUE;
1939}
1940
1941static int tls_process_ske_psk_preamble(SSL *s, PACKET *pkt)
1942{
1943#ifndef OPENSSL_NO_PSK
1944    PACKET psk_identity_hint;
1945
1946    /* PSK ciphersuites are preceded by an identity hint */
1947
1948    if (!PACKET_get_length_prefixed_2(pkt, &psk_identity_hint)) {
1949        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1950        return 0;
1951    }
1952
1953    /*
1954     * Store PSK identity hint for later use, hint is used in
1955     * tls_construct_client_key_exchange.  Assume that the maximum length of
1956     * a PSK identity hint can be as long as the maximum length of a PSK
1957     * identity.
1958     */
1959    if (PACKET_remaining(&psk_identity_hint) > PSK_MAX_IDENTITY_LEN) {
1960        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_DATA_LENGTH_TOO_LONG);
1961        return 0;
1962    }
1963
1964    if (PACKET_remaining(&psk_identity_hint) == 0) {
1965        OPENSSL_free(s->session->psk_identity_hint);
1966        s->session->psk_identity_hint = NULL;
1967    } else if (!PACKET_strndup(&psk_identity_hint,
1968                               &s->session->psk_identity_hint)) {
1969        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1970        return 0;
1971    }
1972
1973    return 1;
1974#else
1975    SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1976    return 0;
1977#endif
1978}
1979
1980static int tls_process_ske_srp(SSL *s, PACKET *pkt, EVP_PKEY **pkey)
1981{
1982#ifndef OPENSSL_NO_SRP
1983    PACKET prime, generator, salt, server_pub;
1984
1985    if (!PACKET_get_length_prefixed_2(pkt, &prime)
1986        || !PACKET_get_length_prefixed_2(pkt, &generator)
1987        || !PACKET_get_length_prefixed_1(pkt, &salt)
1988        || !PACKET_get_length_prefixed_2(pkt, &server_pub)) {
1989        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1990        return 0;
1991    }
1992
1993    if ((s->srp_ctx.N =
1994         BN_bin2bn(PACKET_data(&prime),
1995                   (int)PACKET_remaining(&prime), NULL)) == NULL
1996        || (s->srp_ctx.g =
1997            BN_bin2bn(PACKET_data(&generator),
1998                      (int)PACKET_remaining(&generator), NULL)) == NULL
1999        || (s->srp_ctx.s =
2000            BN_bin2bn(PACKET_data(&salt),
2001                      (int)PACKET_remaining(&salt), NULL)) == NULL
2002        || (s->srp_ctx.B =
2003            BN_bin2bn(PACKET_data(&server_pub),
2004                      (int)PACKET_remaining(&server_pub), NULL)) == NULL) {
2005        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BN_LIB);
2006        return 0;
2007    }
2008
2009    if (!srp_verify_server_param(s)) {
2010        /* SSLfatal() already called */
2011        return 0;
2012    }
2013
2014    /* We must check if there is a certificate */
2015    if (s->s3.tmp.new_cipher->algorithm_auth & (SSL_aRSA | SSL_aDSS))
2016        *pkey = X509_get0_pubkey(s->session->peer);
2017
2018    return 1;
2019#else
2020    SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2021    return 0;
2022#endif
2023}
2024
2025static int tls_process_ske_dhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey)
2026{
2027    PACKET prime, generator, pub_key;
2028    EVP_PKEY *peer_tmp = NULL;
2029    BIGNUM *p = NULL, *g = NULL, *bnpub_key = NULL;
2030    EVP_PKEY_CTX *pctx = NULL;
2031    OSSL_PARAM *params = NULL;
2032    OSSL_PARAM_BLD *tmpl = NULL;
2033    int ret = 0;
2034
2035    if (!PACKET_get_length_prefixed_2(pkt, &prime)
2036        || !PACKET_get_length_prefixed_2(pkt, &generator)
2037        || !PACKET_get_length_prefixed_2(pkt, &pub_key)) {
2038        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2039        return 0;
2040    }
2041
2042    p = BN_bin2bn(PACKET_data(&prime), (int)PACKET_remaining(&prime), NULL);
2043    g = BN_bin2bn(PACKET_data(&generator), (int)PACKET_remaining(&generator),
2044                  NULL);
2045    bnpub_key = BN_bin2bn(PACKET_data(&pub_key),
2046                          (int)PACKET_remaining(&pub_key), NULL);
2047    if (p == NULL || g == NULL || bnpub_key == NULL) {
2048        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BN_LIB);
2049        goto err;
2050    }
2051
2052    tmpl = OSSL_PARAM_BLD_new();
2053    if (tmpl == NULL
2054            || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_P, p)
2055            || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_G, g)
2056            || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_PUB_KEY,
2057                                       bnpub_key)
2058            || (params = OSSL_PARAM_BLD_to_param(tmpl)) == NULL) {
2059        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2060        goto err;
2061    }
2062
2063    pctx = EVP_PKEY_CTX_new_from_name(s->ctx->libctx, "DH", s->ctx->propq);
2064    if (pctx == NULL) {
2065        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2066        goto err;
2067    }
2068    if (EVP_PKEY_fromdata_init(pctx) <= 0
2069            || EVP_PKEY_fromdata(pctx, &peer_tmp, EVP_PKEY_KEYPAIR, params) <= 0) {
2070        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_DH_VALUE);
2071        goto err;
2072    }
2073
2074    EVP_PKEY_CTX_free(pctx);
2075    pctx = EVP_PKEY_CTX_new_from_pkey(s->ctx->libctx, peer_tmp, s->ctx->propq);
2076    if (pctx == NULL
2077            /*
2078             * EVP_PKEY_param_check() will verify that the DH params are using
2079             * a safe prime. In this context, because we're using ephemeral DH,
2080             * we're ok with it not being a safe prime.
2081             * EVP_PKEY_param_check_quick() skips the safe prime check.
2082             */
2083            || EVP_PKEY_param_check_quick(pctx) != 1
2084            || EVP_PKEY_public_check(pctx) != 1) {
2085        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_DH_VALUE);
2086        goto err;
2087    }
2088
2089    if (!ssl_security(s, SSL_SECOP_TMP_DH,
2090                      EVP_PKEY_get_security_bits(peer_tmp),
2091                      0, peer_tmp)) {
2092        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_DH_KEY_TOO_SMALL);
2093        goto err;
2094    }
2095
2096    s->s3.peer_tmp = peer_tmp;
2097    peer_tmp = NULL;
2098
2099    /*
2100     * FIXME: This makes assumptions about which ciphersuites come with
2101     * public keys. We should have a less ad-hoc way of doing this
2102     */
2103    if (s->s3.tmp.new_cipher->algorithm_auth & (SSL_aRSA | SSL_aDSS))
2104        *pkey = X509_get0_pubkey(s->session->peer);
2105    /* else anonymous DH, so no certificate or pkey. */
2106
2107    ret = 1;
2108
2109 err:
2110    OSSL_PARAM_BLD_free(tmpl);
2111    OSSL_PARAM_free(params);
2112    EVP_PKEY_free(peer_tmp);
2113    EVP_PKEY_CTX_free(pctx);
2114    BN_free(p);
2115    BN_free(g);
2116    BN_free(bnpub_key);
2117
2118    return ret;
2119}
2120
2121static int tls_process_ske_ecdhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey)
2122{
2123    PACKET encoded_pt;
2124    unsigned int curve_type, curve_id;
2125
2126    /*
2127     * Extract elliptic curve parameters and the server's ephemeral ECDH
2128     * public key. We only support named (not generic) curves and
2129     * ECParameters in this case is just three bytes.
2130     */
2131    if (!PACKET_get_1(pkt, &curve_type) || !PACKET_get_net_2(pkt, &curve_id)) {
2132        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
2133        return 0;
2134    }
2135    /*
2136     * Check curve is named curve type and one of our preferences, if not
2137     * server has sent an invalid curve.
2138     */
2139    if (curve_type != NAMED_CURVE_TYPE
2140            || !tls1_check_group_id(s, curve_id, 1)) {
2141        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CURVE);
2142        return 0;
2143    }
2144
2145    if ((s->s3.peer_tmp = ssl_generate_param_group(s, curve_id)) == NULL) {
2146        SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2147                 SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS);
2148        return 0;
2149    }
2150
2151    if (!PACKET_get_length_prefixed_1(pkt, &encoded_pt)) {
2152        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2153        return 0;
2154    }
2155
2156    if (EVP_PKEY_set1_encoded_public_key(s->s3.peer_tmp,
2157                                         PACKET_data(&encoded_pt),
2158                                         PACKET_remaining(&encoded_pt)) <= 0) {
2159        SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_ECPOINT);
2160        return 0;
2161    }
2162
2163    /*
2164     * The ECC/TLS specification does not mention the use of DSA to sign
2165     * ECParameters in the server key exchange message. We do support RSA
2166     * and ECDSA.
2167     */
2168    if (s->s3.tmp.new_cipher->algorithm_auth & SSL_aECDSA)
2169        *pkey = X509_get0_pubkey(s->session->peer);
2170    else if (s->s3.tmp.new_cipher->algorithm_auth & SSL_aRSA)
2171        *pkey = X509_get0_pubkey(s->session->peer);
2172    /* else anonymous ECDH, so no certificate or pkey. */
2173
2174    /* Cache the agreed upon group in the SSL_SESSION */
2175    s->session->kex_group = curve_id;
2176    return 1;
2177}
2178
2179MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)
2180{
2181    long alg_k;
2182    EVP_PKEY *pkey = NULL;
2183    EVP_MD_CTX *md_ctx = NULL;
2184    EVP_PKEY_CTX *pctx = NULL;
2185    PACKET save_param_start, signature;
2186
2187    alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
2188
2189    save_param_start = *pkt;
2190
2191    EVP_PKEY_free(s->s3.peer_tmp);
2192    s->s3.peer_tmp = NULL;
2193
2194    if (alg_k & SSL_PSK) {
2195        if (!tls_process_ske_psk_preamble(s, pkt)) {
2196            /* SSLfatal() already called */
2197            goto err;
2198        }
2199    }
2200
2201    /* Nothing else to do for plain PSK or RSAPSK */
2202    if (alg_k & (SSL_kPSK | SSL_kRSAPSK)) {
2203    } else if (alg_k & SSL_kSRP) {
2204        if (!tls_process_ske_srp(s, pkt, &pkey)) {
2205            /* SSLfatal() already called */
2206            goto err;
2207        }
2208    } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
2209        if (!tls_process_ske_dhe(s, pkt, &pkey)) {
2210            /* SSLfatal() already called */
2211            goto err;
2212        }
2213    } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
2214        if (!tls_process_ske_ecdhe(s, pkt, &pkey)) {
2215            /* SSLfatal() already called */
2216            goto err;
2217        }
2218    } else if (alg_k) {
2219        SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
2220        goto err;
2221    }
2222
2223    /* if it was signed, check the signature */
2224    if (pkey != NULL) {
2225        PACKET params;
2226        const EVP_MD *md = NULL;
2227        unsigned char *tbs;
2228        size_t tbslen;
2229        int rv;
2230
2231        /*
2232         * |pkt| now points to the beginning of the signature, so the difference
2233         * equals the length of the parameters.
2234         */
2235        if (!PACKET_get_sub_packet(&save_param_start, &params,
2236                                   PACKET_remaining(&save_param_start) -
2237                                   PACKET_remaining(pkt))) {
2238            SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_INTERNAL_ERROR);
2239            goto err;
2240        }
2241
2242        if (SSL_USE_SIGALGS(s)) {
2243            unsigned int sigalg;
2244
2245            if (!PACKET_get_net_2(pkt, &sigalg)) {
2246                SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
2247                goto err;
2248            }
2249            if (tls12_check_peer_sigalg(s, sigalg, pkey) <=0) {
2250                /* SSLfatal() already called */
2251                goto err;
2252            }
2253        } else if (!tls1_set_peer_legacy_sigalg(s, pkey)) {
2254            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2255                     SSL_R_LEGACY_SIGALG_DISALLOWED_OR_UNSUPPORTED);
2256            goto err;
2257        }
2258
2259        if (!tls1_lookup_md(s->ctx, s->s3.tmp.peer_sigalg, &md)) {
2260            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2261                     SSL_R_NO_SUITABLE_DIGEST_ALGORITHM);
2262            goto err;
2263        }
2264        if (SSL_USE_SIGALGS(s))
2265            OSSL_TRACE1(TLS, "USING TLSv1.2 HASH %s\n",
2266                        md == NULL ? "n/a" : EVP_MD_get0_name(md));
2267
2268        if (!PACKET_get_length_prefixed_2(pkt, &signature)
2269            || PACKET_remaining(pkt) != 0) {
2270            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2271            goto err;
2272        }
2273
2274        md_ctx = EVP_MD_CTX_new();
2275        if (md_ctx == NULL) {
2276            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2277            goto err;
2278        }
2279
2280        if (EVP_DigestVerifyInit_ex(md_ctx, &pctx,
2281                                    md == NULL ? NULL : EVP_MD_get0_name(md),
2282                                    s->ctx->libctx, s->ctx->propq, pkey,
2283                                    NULL) <= 0) {
2284            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
2285            goto err;
2286        }
2287        if (SSL_USE_PSS(s)) {
2288            if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
2289                || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx,
2290                                                RSA_PSS_SALTLEN_DIGEST) <= 0) {
2291                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
2292                goto err;
2293            }
2294        }
2295        tbslen = construct_key_exchange_tbs(s, &tbs, PACKET_data(&params),
2296                                            PACKET_remaining(&params));
2297        if (tbslen == 0) {
2298            /* SSLfatal() already called */
2299            goto err;
2300        }
2301
2302        rv = EVP_DigestVerify(md_ctx, PACKET_data(&signature),
2303                              PACKET_remaining(&signature), tbs, tbslen);
2304        OPENSSL_free(tbs);
2305        if (rv <= 0) {
2306            SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_R_BAD_SIGNATURE);
2307            goto err;
2308        }
2309        EVP_MD_CTX_free(md_ctx);
2310        md_ctx = NULL;
2311    } else {
2312        /* aNULL, aSRP or PSK do not need public keys */
2313        if (!(s->s3.tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP))
2314            && !(alg_k & SSL_PSK)) {
2315            /* Might be wrong key type, check it */
2316            if (ssl3_check_cert_and_algorithm(s)) {
2317                SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_DATA);
2318            }
2319            /* else this shouldn't happen, SSLfatal() already called */
2320            goto err;
2321        }
2322        /* still data left over */
2323        if (PACKET_remaining(pkt) != 0) {
2324            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_EXTRA_DATA_IN_MESSAGE);
2325            goto err;
2326        }
2327    }
2328
2329    return MSG_PROCESS_CONTINUE_READING;
2330 err:
2331    EVP_MD_CTX_free(md_ctx);
2332    return MSG_PROCESS_ERROR;
2333}
2334
2335MSG_PROCESS_RETURN tls_process_certificate_request(SSL *s, PACKET *pkt)
2336{
2337    size_t i;
2338
2339    /* Clear certificate validity flags */
2340    for (i = 0; i < SSL_PKEY_NUM; i++)
2341        s->s3.tmp.valid_flags[i] = 0;
2342
2343    if (SSL_IS_TLS13(s)) {
2344        PACKET reqctx, extensions;
2345        RAW_EXTENSION *rawexts = NULL;
2346
2347        if ((s->shutdown & SSL_SENT_SHUTDOWN) != 0) {
2348            /*
2349             * We already sent close_notify. This can only happen in TLSv1.3
2350             * post-handshake messages. We can't reasonably respond to this, so
2351             * we just ignore it
2352             */
2353            return MSG_PROCESS_FINISHED_READING;
2354        }
2355
2356        /* Free and zero certificate types: it is not present in TLS 1.3 */
2357        OPENSSL_free(s->s3.tmp.ctype);
2358        s->s3.tmp.ctype = NULL;
2359        s->s3.tmp.ctype_len = 0;
2360        OPENSSL_free(s->pha_context);
2361        s->pha_context = NULL;
2362        s->pha_context_len = 0;
2363
2364        if (!PACKET_get_length_prefixed_1(pkt, &reqctx) ||
2365            !PACKET_memdup(&reqctx, &s->pha_context, &s->pha_context_len)) {
2366            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2367            return MSG_PROCESS_ERROR;
2368        }
2369
2370        if (!PACKET_get_length_prefixed_2(pkt, &extensions)) {
2371            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
2372            return MSG_PROCESS_ERROR;
2373        }
2374        if (!tls_collect_extensions(s, &extensions,
2375                                    SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
2376                                    &rawexts, NULL, 1)
2377            || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
2378                                         rawexts, NULL, 0, 1)) {
2379            /* SSLfatal() already called */
2380            OPENSSL_free(rawexts);
2381            return MSG_PROCESS_ERROR;
2382        }
2383        OPENSSL_free(rawexts);
2384        if (!tls1_process_sigalgs(s)) {
2385            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_LENGTH);
2386            return MSG_PROCESS_ERROR;
2387        }
2388    } else {
2389        PACKET ctypes;
2390
2391        /* get the certificate types */
2392        if (!PACKET_get_length_prefixed_1(pkt, &ctypes)) {
2393            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2394            return MSG_PROCESS_ERROR;
2395        }
2396
2397        if (!PACKET_memdup(&ctypes, &s->s3.tmp.ctype, &s->s3.tmp.ctype_len)) {
2398            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2399            return MSG_PROCESS_ERROR;
2400        }
2401
2402        if (SSL_USE_SIGALGS(s)) {
2403            PACKET sigalgs;
2404
2405            if (!PACKET_get_length_prefixed_2(pkt, &sigalgs)) {
2406                SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2407                return MSG_PROCESS_ERROR;
2408            }
2409
2410            /*
2411             * Despite this being for certificates, preserve compatibility
2412             * with pre-TLS 1.3 and use the regular sigalgs field.
2413             */
2414            if (!tls1_save_sigalgs(s, &sigalgs, 0)) {
2415                SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2416                         SSL_R_SIGNATURE_ALGORITHMS_ERROR);
2417                return MSG_PROCESS_ERROR;
2418            }
2419            if (!tls1_process_sigalgs(s)) {
2420                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2421                return MSG_PROCESS_ERROR;
2422            }
2423        }
2424
2425        /* get the CA RDNs */
2426        if (!parse_ca_names(s, pkt)) {
2427            /* SSLfatal() already called */
2428            return MSG_PROCESS_ERROR;
2429        }
2430    }
2431
2432    if (PACKET_remaining(pkt) != 0) {
2433        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2434        return MSG_PROCESS_ERROR;
2435    }
2436
2437    /* we should setup a certificate to return.... */
2438    s->s3.tmp.cert_req = 1;
2439
2440    /*
2441     * In TLSv1.3 we don't prepare the client certificate yet. We wait until
2442     * after the CertificateVerify message has been received. This is because
2443     * in TLSv1.3 the CertificateRequest arrives before the Certificate message
2444     * but in TLSv1.2 it is the other way around. We want to make sure that
2445     * SSL_get1_peer_certificate() returns something sensible in
2446     * client_cert_cb.
2447     */
2448    if (SSL_IS_TLS13(s) && s->post_handshake_auth != SSL_PHA_REQUESTED)
2449        return MSG_PROCESS_CONTINUE_READING;
2450
2451    return MSG_PROCESS_CONTINUE_PROCESSING;
2452}
2453
2454MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL *s, PACKET *pkt)
2455{
2456    unsigned int ticklen;
2457    unsigned long ticket_lifetime_hint, age_add = 0;
2458    unsigned int sess_len;
2459    RAW_EXTENSION *exts = NULL;
2460    PACKET nonce;
2461    EVP_MD *sha256 = NULL;
2462
2463    PACKET_null_init(&nonce);
2464
2465    if (!PACKET_get_net_4(pkt, &ticket_lifetime_hint)
2466        || (SSL_IS_TLS13(s)
2467            && (!PACKET_get_net_4(pkt, &age_add)
2468                || !PACKET_get_length_prefixed_1(pkt, &nonce)))
2469        || !PACKET_get_net_2(pkt, &ticklen)
2470        || (SSL_IS_TLS13(s) ? (ticklen == 0 || PACKET_remaining(pkt) < ticklen)
2471                            : PACKET_remaining(pkt) != ticklen)) {
2472        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2473        goto err;
2474    }
2475
2476    /*
2477     * Server is allowed to change its mind (in <=TLSv1.2) and send an empty
2478     * ticket. We already checked this TLSv1.3 case above, so it should never
2479     * be 0 here in that instance
2480     */
2481    if (ticklen == 0)
2482        return MSG_PROCESS_CONTINUE_READING;
2483
2484    /*
2485     * Sessions must be immutable once they go into the session cache. Otherwise
2486     * we can get multi-thread problems. Therefore we don't "update" sessions,
2487     * we replace them with a duplicate. In TLSv1.3 we need to do this every
2488     * time a NewSessionTicket arrives because those messages arrive
2489     * post-handshake and the session may have already gone into the session
2490     * cache.
2491     */
2492    if (SSL_IS_TLS13(s) || s->session->session_id_length > 0) {
2493        SSL_SESSION *new_sess;
2494
2495        /*
2496         * We reused an existing session, so we need to replace it with a new
2497         * one
2498         */
2499        if ((new_sess = ssl_session_dup(s->session, 0)) == 0) {
2500            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2501            goto err;
2502        }
2503
2504        if ((s->session_ctx->session_cache_mode & SSL_SESS_CACHE_CLIENT) != 0
2505                && !SSL_IS_TLS13(s)) {
2506            /*
2507             * In TLSv1.2 and below the arrival of a new tickets signals that
2508             * any old ticket we were using is now out of date, so we remove the
2509             * old session from the cache. We carry on if this fails
2510             */
2511            SSL_CTX_remove_session(s->session_ctx, s->session);
2512        }
2513
2514        SSL_SESSION_free(s->session);
2515        s->session = new_sess;
2516    }
2517
2518    s->session->time = time(NULL);
2519    ssl_session_calculate_timeout(s->session);
2520
2521    OPENSSL_free(s->session->ext.tick);
2522    s->session->ext.tick = NULL;
2523    s->session->ext.ticklen = 0;
2524
2525    s->session->ext.tick = OPENSSL_malloc(ticklen);
2526    if (s->session->ext.tick == NULL) {
2527        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2528        goto err;
2529    }
2530    if (!PACKET_copy_bytes(pkt, s->session->ext.tick, ticklen)) {
2531        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2532        goto err;
2533    }
2534
2535    s->session->ext.tick_lifetime_hint = ticket_lifetime_hint;
2536    s->session->ext.tick_age_add = age_add;
2537    s->session->ext.ticklen = ticklen;
2538
2539    if (SSL_IS_TLS13(s)) {
2540        PACKET extpkt;
2541
2542        if (!PACKET_as_length_prefixed_2(pkt, &extpkt)
2543                || PACKET_remaining(pkt) != 0) {
2544            SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2545            goto err;
2546        }
2547
2548        if (!tls_collect_extensions(s, &extpkt,
2549                                    SSL_EXT_TLS1_3_NEW_SESSION_TICKET, &exts,
2550                                    NULL, 1)
2551                || !tls_parse_all_extensions(s,
2552                                             SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
2553                                             exts, NULL, 0, 1)) {
2554            /* SSLfatal() already called */
2555            goto err;
2556        }
2557    }
2558
2559    /*
2560     * There are two ways to detect a resumed ticket session. One is to set
2561     * an appropriate session ID and then the server must return a match in
2562     * ServerHello. This allows the normal client session ID matching to work
2563     * and we know much earlier that the ticket has been accepted. The
2564     * other way is to set zero length session ID when the ticket is
2565     * presented and rely on the handshake to determine session resumption.
2566     * We choose the former approach because this fits in with assumptions
2567     * elsewhere in OpenSSL. The session ID is set to the SHA256 hash of the
2568     * ticket.
2569     */
2570    sha256 = EVP_MD_fetch(s->ctx->libctx, "SHA2-256", s->ctx->propq);
2571    if (sha256 == NULL) {
2572        /* Error is already recorded */
2573        SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
2574        goto err;
2575    }
2576    /*
2577     * We use sess_len here because EVP_Digest expects an int
2578     * but s->session->session_id_length is a size_t
2579     */
2580    if (!EVP_Digest(s->session->ext.tick, ticklen,
2581                    s->session->session_id, &sess_len,
2582                    sha256, NULL)) {
2583        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
2584        goto err;
2585    }
2586    EVP_MD_free(sha256);
2587    sha256 = NULL;
2588    s->session->session_id_length = sess_len;
2589    s->session->not_resumable = 0;
2590
2591    /* This is a standalone message in TLSv1.3, so there is no more to read */
2592    if (SSL_IS_TLS13(s)) {
2593        const EVP_MD *md = ssl_handshake_md(s);
2594        int hashleni = EVP_MD_get_size(md);
2595        size_t hashlen;
2596        static const unsigned char nonce_label[] = "resumption";
2597
2598        /* Ensure cast to size_t is safe */
2599        if (!ossl_assert(hashleni >= 0)) {
2600            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2601            goto err;
2602        }
2603        hashlen = (size_t)hashleni;
2604
2605        if (!tls13_hkdf_expand(s, md, s->resumption_master_secret,
2606                               nonce_label,
2607                               sizeof(nonce_label) - 1,
2608                               PACKET_data(&nonce),
2609                               PACKET_remaining(&nonce),
2610                               s->session->master_key,
2611                               hashlen, 1)) {
2612            /* SSLfatal() already called */
2613            goto err;
2614        }
2615        s->session->master_key_length = hashlen;
2616
2617        OPENSSL_free(exts);
2618        ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
2619        return MSG_PROCESS_FINISHED_READING;
2620    }
2621
2622    return MSG_PROCESS_CONTINUE_READING;
2623 err:
2624    EVP_MD_free(sha256);
2625    OPENSSL_free(exts);
2626    return MSG_PROCESS_ERROR;
2627}
2628
2629/*
2630 * In TLSv1.3 this is called from the extensions code, otherwise it is used to
2631 * parse a separate message. Returns 1 on success or 0 on failure
2632 */
2633int tls_process_cert_status_body(SSL *s, PACKET *pkt)
2634{
2635    size_t resplen;
2636    unsigned int type;
2637
2638    if (!PACKET_get_1(pkt, &type)
2639        || type != TLSEXT_STATUSTYPE_ocsp) {
2640        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_UNSUPPORTED_STATUS_TYPE);
2641        return 0;
2642    }
2643    if (!PACKET_get_net_3_len(pkt, &resplen)
2644        || PACKET_remaining(pkt) != resplen) {
2645        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2646        return 0;
2647    }
2648    s->ext.ocsp.resp = OPENSSL_malloc(resplen);
2649    if (s->ext.ocsp.resp == NULL) {
2650        s->ext.ocsp.resp_len = 0;
2651        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2652        return 0;
2653    }
2654    s->ext.ocsp.resp_len = resplen;
2655    if (!PACKET_copy_bytes(pkt, s->ext.ocsp.resp, resplen)) {
2656        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2657        return 0;
2658    }
2659
2660    return 1;
2661}
2662
2663
2664MSG_PROCESS_RETURN tls_process_cert_status(SSL *s, PACKET *pkt)
2665{
2666    if (!tls_process_cert_status_body(s, pkt)) {
2667        /* SSLfatal() already called */
2668        return MSG_PROCESS_ERROR;
2669    }
2670
2671    return MSG_PROCESS_CONTINUE_READING;
2672}
2673
2674/*
2675 * Perform miscellaneous checks and processing after we have received the
2676 * server's initial flight. In TLS1.3 this is after the Server Finished message.
2677 * In <=TLS1.2 this is after the ServerDone message. Returns 1 on success or 0
2678 * on failure.
2679 */
2680int tls_process_initial_server_flight(SSL *s)
2681{
2682    /*
2683     * at this point we check that we have the required stuff from
2684     * the server
2685     */
2686    if (!ssl3_check_cert_and_algorithm(s)) {
2687        /* SSLfatal() already called */
2688        return 0;
2689    }
2690
2691    /*
2692     * Call the ocsp status callback if needed. The |ext.ocsp.resp| and
2693     * |ext.ocsp.resp_len| values will be set if we actually received a status
2694     * message, or NULL and -1 otherwise
2695     */
2696    if (s->ext.status_type != TLSEXT_STATUSTYPE_nothing
2697            && s->ctx->ext.status_cb != NULL) {
2698        int ret = s->ctx->ext.status_cb(s, s->ctx->ext.status_arg);
2699
2700        if (ret == 0) {
2701            SSLfatal(s, SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE,
2702                     SSL_R_INVALID_STATUS_RESPONSE);
2703            return 0;
2704        }
2705        if (ret < 0) {
2706            SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2707                     SSL_R_OCSP_CALLBACK_FAILURE);
2708            return 0;
2709        }
2710    }
2711#ifndef OPENSSL_NO_CT
2712    if (s->ct_validation_callback != NULL) {
2713        /* Note we validate the SCTs whether or not we abort on error */
2714        if (!ssl_validate_ct(s) && (s->verify_mode & SSL_VERIFY_PEER)) {
2715            /* SSLfatal() already called */
2716            return 0;
2717        }
2718    }
2719#endif
2720
2721    return 1;
2722}
2723
2724MSG_PROCESS_RETURN tls_process_server_done(SSL *s, PACKET *pkt)
2725{
2726    if (PACKET_remaining(pkt) > 0) {
2727        /* should contain no data */
2728        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2729        return MSG_PROCESS_ERROR;
2730    }
2731#ifndef OPENSSL_NO_SRP
2732    if (s->s3.tmp.new_cipher->algorithm_mkey & SSL_kSRP) {
2733        if (ssl_srp_calc_a_param_intern(s) <= 0) {
2734            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_SRP_A_CALC);
2735            return MSG_PROCESS_ERROR;
2736        }
2737    }
2738#endif
2739
2740    if (!tls_process_initial_server_flight(s)) {
2741        /* SSLfatal() already called */
2742        return MSG_PROCESS_ERROR;
2743    }
2744
2745    return MSG_PROCESS_FINISHED_READING;
2746}
2747
2748static int tls_construct_cke_psk_preamble(SSL *s, WPACKET *pkt)
2749{
2750#ifndef OPENSSL_NO_PSK
2751    int ret = 0;
2752    /*
2753     * The callback needs PSK_MAX_IDENTITY_LEN + 1 bytes to return a
2754     * \0-terminated identity. The last byte is for us for simulating
2755     * strnlen.
2756     */
2757    char identity[PSK_MAX_IDENTITY_LEN + 1];
2758    size_t identitylen = 0;
2759    unsigned char psk[PSK_MAX_PSK_LEN];
2760    unsigned char *tmppsk = NULL;
2761    char *tmpidentity = NULL;
2762    size_t psklen = 0;
2763
2764    if (s->psk_client_callback == NULL) {
2765        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PSK_NO_CLIENT_CB);
2766        goto err;
2767    }
2768
2769    memset(identity, 0, sizeof(identity));
2770
2771    psklen = s->psk_client_callback(s, s->session->psk_identity_hint,
2772                                    identity, sizeof(identity) - 1,
2773                                    psk, sizeof(psk));
2774
2775    if (psklen > PSK_MAX_PSK_LEN) {
2776        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, ERR_R_INTERNAL_ERROR);
2777        psklen = PSK_MAX_PSK_LEN;   /* Avoid overrunning the array on cleanse */
2778        goto err;
2779    } else if (psklen == 0) {
2780        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_PSK_IDENTITY_NOT_FOUND);
2781        goto err;
2782    }
2783
2784    identitylen = strlen(identity);
2785    if (identitylen > PSK_MAX_IDENTITY_LEN) {
2786        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2787        goto err;
2788    }
2789
2790    tmppsk = OPENSSL_memdup(psk, psklen);
2791    tmpidentity = OPENSSL_strdup(identity);
2792    if (tmppsk == NULL || tmpidentity == NULL) {
2793        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2794        goto err;
2795    }
2796
2797    OPENSSL_free(s->s3.tmp.psk);
2798    s->s3.tmp.psk = tmppsk;
2799    s->s3.tmp.psklen = psklen;
2800    tmppsk = NULL;
2801    OPENSSL_free(s->session->psk_identity);
2802    s->session->psk_identity = tmpidentity;
2803    tmpidentity = NULL;
2804
2805    if (!WPACKET_sub_memcpy_u16(pkt, identity, identitylen))  {
2806        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2807        goto err;
2808    }
2809
2810    ret = 1;
2811
2812 err:
2813    OPENSSL_cleanse(psk, psklen);
2814    OPENSSL_cleanse(identity, sizeof(identity));
2815    OPENSSL_clear_free(tmppsk, psklen);
2816    OPENSSL_clear_free(tmpidentity, identitylen);
2817
2818    return ret;
2819#else
2820    SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2821    return 0;
2822#endif
2823}
2824
2825static int tls_construct_cke_rsa(SSL *s, WPACKET *pkt)
2826{
2827    unsigned char *encdata = NULL;
2828    EVP_PKEY *pkey = NULL;
2829    EVP_PKEY_CTX *pctx = NULL;
2830    size_t enclen;
2831    unsigned char *pms = NULL;
2832    size_t pmslen = 0;
2833
2834    if (s->session->peer == NULL) {
2835        /*
2836         * We should always have a server certificate with SSL_kRSA.
2837         */
2838        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2839        return 0;
2840    }
2841
2842    pkey = X509_get0_pubkey(s->session->peer);
2843    if (!EVP_PKEY_is_a(pkey, "RSA")) {
2844        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2845        return 0;
2846    }
2847
2848    pmslen = SSL_MAX_MASTER_KEY_LENGTH;
2849    pms = OPENSSL_malloc(pmslen);
2850    if (pms == NULL) {
2851        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2852        return 0;
2853    }
2854
2855    pms[0] = s->client_version >> 8;
2856    pms[1] = s->client_version & 0xff;
2857    if (RAND_bytes_ex(s->ctx->libctx, pms + 2, pmslen - 2, 0) <= 0) {
2858        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2859        goto err;
2860    }
2861
2862    /* Fix buf for TLS and beyond */
2863    if (s->version > SSL3_VERSION && !WPACKET_start_sub_packet_u16(pkt)) {
2864        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2865        goto err;
2866    }
2867
2868    pctx = EVP_PKEY_CTX_new_from_pkey(s->ctx->libctx, pkey, s->ctx->propq);
2869    if (pctx == NULL || EVP_PKEY_encrypt_init(pctx) <= 0
2870        || EVP_PKEY_encrypt(pctx, NULL, &enclen, pms, pmslen) <= 0) {
2871        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
2872        goto err;
2873    }
2874    if (!WPACKET_allocate_bytes(pkt, enclen, &encdata)
2875            || EVP_PKEY_encrypt(pctx, encdata, &enclen, pms, pmslen) <= 0) {
2876        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_RSA_ENCRYPT);
2877        goto err;
2878    }
2879    EVP_PKEY_CTX_free(pctx);
2880    pctx = NULL;
2881
2882    /* Fix buf for TLS and beyond */
2883    if (s->version > SSL3_VERSION && !WPACKET_close(pkt)) {
2884        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2885        goto err;
2886    }
2887
2888    /* Log the premaster secret, if logging is enabled. */
2889    if (!ssl_log_rsa_client_key_exchange(s, encdata, enclen, pms, pmslen)) {
2890        /* SSLfatal() already called */
2891        goto err;
2892    }
2893
2894    s->s3.tmp.pms = pms;
2895    s->s3.tmp.pmslen = pmslen;
2896
2897    return 1;
2898 err:
2899    OPENSSL_clear_free(pms, pmslen);
2900    EVP_PKEY_CTX_free(pctx);
2901
2902    return 0;
2903}
2904
2905static int tls_construct_cke_dhe(SSL *s, WPACKET *pkt)
2906{
2907    EVP_PKEY *ckey = NULL, *skey = NULL;
2908    unsigned char *keybytes = NULL;
2909    int prime_len;
2910    unsigned char *encoded_pub = NULL;
2911    size_t encoded_pub_len, pad_len;
2912    int ret = 0;
2913
2914    skey = s->s3.peer_tmp;
2915    if (skey == NULL) {
2916        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2917        goto err;
2918    }
2919
2920    ckey = ssl_generate_pkey(s, skey);
2921    if (ckey == NULL) {
2922        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2923        goto err;
2924    }
2925
2926    if (ssl_derive(s, ckey, skey, 0) == 0) {
2927        /* SSLfatal() already called */
2928        goto err;
2929    }
2930
2931    /* send off the data */
2932
2933    /* Generate encoding of server key */
2934    encoded_pub_len = EVP_PKEY_get1_encoded_public_key(ckey, &encoded_pub);
2935    if (encoded_pub_len == 0) {
2936        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2937        EVP_PKEY_free(ckey);
2938        return EXT_RETURN_FAIL;
2939    }
2940
2941    /*
2942     * For interoperability with some versions of the Microsoft TLS
2943     * stack, we need to zero pad the DHE pub key to the same length
2944     * as the prime.
2945     */
2946    prime_len = EVP_PKEY_get_size(ckey);
2947    pad_len = prime_len - encoded_pub_len;
2948    if (pad_len > 0) {
2949        if (!WPACKET_sub_allocate_bytes_u16(pkt, pad_len, &keybytes)) {
2950            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2951            goto err;
2952        }
2953        memset(keybytes, 0, pad_len);
2954    }
2955
2956    if (!WPACKET_sub_memcpy_u16(pkt, encoded_pub, encoded_pub_len)) {
2957        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2958        goto err;
2959    }
2960
2961    ret = 1;
2962 err:
2963    OPENSSL_free(encoded_pub);
2964    EVP_PKEY_free(ckey);
2965    return ret;
2966}
2967
2968static int tls_construct_cke_ecdhe(SSL *s, WPACKET *pkt)
2969{
2970    unsigned char *encodedPoint = NULL;
2971    size_t encoded_pt_len = 0;
2972    EVP_PKEY *ckey = NULL, *skey = NULL;
2973    int ret = 0;
2974
2975    skey = s->s3.peer_tmp;
2976    if (skey == NULL) {
2977        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2978        return 0;
2979    }
2980
2981    ckey = ssl_generate_pkey(s, skey);
2982    if (ckey == NULL) {
2983        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2984        goto err;
2985    }
2986
2987    if (ssl_derive(s, ckey, skey, 0) == 0) {
2988        /* SSLfatal() already called */
2989        goto err;
2990    }
2991
2992    /* Generate encoding of client key */
2993    encoded_pt_len = EVP_PKEY_get1_encoded_public_key(ckey, &encodedPoint);
2994
2995    if (encoded_pt_len == 0) {
2996        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EC_LIB);
2997        goto err;
2998    }
2999
3000    if (!WPACKET_sub_memcpy_u8(pkt, encodedPoint, encoded_pt_len)) {
3001        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3002        goto err;
3003    }
3004
3005    ret = 1;
3006 err:
3007    OPENSSL_free(encodedPoint);
3008    EVP_PKEY_free(ckey);
3009    return ret;
3010}
3011
3012static int tls_construct_cke_gost(SSL *s, WPACKET *pkt)
3013{
3014#ifndef OPENSSL_NO_GOST
3015    /* GOST key exchange message creation */
3016    EVP_PKEY_CTX *pkey_ctx = NULL;
3017    X509 *peer_cert;
3018    size_t msglen;
3019    unsigned int md_len;
3020    unsigned char shared_ukm[32], tmp[256];
3021    EVP_MD_CTX *ukm_hash = NULL;
3022    int dgst_nid = NID_id_GostR3411_94;
3023    unsigned char *pms = NULL;
3024    size_t pmslen = 0;
3025
3026    if ((s->s3.tmp.new_cipher->algorithm_auth & SSL_aGOST12) != 0)
3027        dgst_nid = NID_id_GostR3411_2012_256;
3028
3029    /*
3030     * Get server certificate PKEY and create ctx from it
3031     */
3032    peer_cert = s->session->peer;
3033    if (peer_cert == NULL) {
3034        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3035                 SSL_R_NO_GOST_CERTIFICATE_SENT_BY_PEER);
3036        return 0;
3037    }
3038
3039    pkey_ctx = EVP_PKEY_CTX_new_from_pkey(s->ctx->libctx,
3040                                          X509_get0_pubkey(peer_cert),
3041                                          s->ctx->propq);
3042    if (pkey_ctx == NULL) {
3043        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3044        return 0;
3045    }
3046    /*
3047     * If we have send a certificate, and certificate key
3048     * parameters match those of server certificate, use
3049     * certificate key for key exchange
3050     */
3051
3052    /* Otherwise, generate ephemeral key pair */
3053    pmslen = 32;
3054    pms = OPENSSL_malloc(pmslen);
3055    if (pms == NULL) {
3056        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3057        goto err;
3058    }
3059
3060    if (EVP_PKEY_encrypt_init(pkey_ctx) <= 0
3061        /* Generate session key
3062         */
3063        || RAND_bytes_ex(s->ctx->libctx, pms, pmslen, 0) <= 0) {
3064        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3065        goto err;
3066    };
3067    /*
3068     * Compute shared IV and store it in algorithm-specific context
3069     * data
3070     */
3071    ukm_hash = EVP_MD_CTX_new();
3072    if (ukm_hash == NULL
3073        || EVP_DigestInit(ukm_hash, EVP_get_digestbynid(dgst_nid)) <= 0
3074        || EVP_DigestUpdate(ukm_hash, s->s3.client_random,
3075                            SSL3_RANDOM_SIZE) <= 0
3076        || EVP_DigestUpdate(ukm_hash, s->s3.server_random,
3077                            SSL3_RANDOM_SIZE) <= 0
3078        || EVP_DigestFinal_ex(ukm_hash, shared_ukm, &md_len) <= 0) {
3079        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3080        goto err;
3081    }
3082    EVP_MD_CTX_free(ukm_hash);
3083    ukm_hash = NULL;
3084    if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
3085                          EVP_PKEY_CTRL_SET_IV, 8, shared_ukm) <= 0) {
3086        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
3087        goto err;
3088    }
3089    /* Make GOST keytransport blob message */
3090    /*
3091     * Encapsulate it into sequence
3092     */
3093    msglen = 255;
3094    if (EVP_PKEY_encrypt(pkey_ctx, tmp, &msglen, pms, pmslen) <= 0) {
3095        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
3096        goto err;
3097    }
3098
3099    if (!WPACKET_put_bytes_u8(pkt, V_ASN1_SEQUENCE | V_ASN1_CONSTRUCTED)
3100            || (msglen >= 0x80 && !WPACKET_put_bytes_u8(pkt, 0x81))
3101            || !WPACKET_sub_memcpy_u8(pkt, tmp, msglen)) {
3102        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3103        goto err;
3104    }
3105
3106    EVP_PKEY_CTX_free(pkey_ctx);
3107    s->s3.tmp.pms = pms;
3108    s->s3.tmp.pmslen = pmslen;
3109
3110    return 1;
3111 err:
3112    EVP_PKEY_CTX_free(pkey_ctx);
3113    OPENSSL_clear_free(pms, pmslen);
3114    EVP_MD_CTX_free(ukm_hash);
3115    return 0;
3116#else
3117    SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3118    return 0;
3119#endif
3120}
3121
3122#ifndef OPENSSL_NO_GOST
3123int ossl_gost18_cke_cipher_nid(const SSL *s)
3124{
3125    if ((s->s3.tmp.new_cipher->algorithm_enc & SSL_MAGMA) != 0)
3126        return NID_magma_ctr;
3127    else if ((s->s3.tmp.new_cipher->algorithm_enc & SSL_KUZNYECHIK) != 0)
3128        return NID_kuznyechik_ctr;
3129
3130    return NID_undef;
3131}
3132
3133int ossl_gost_ukm(const SSL *s, unsigned char *dgst_buf)
3134{
3135    EVP_MD_CTX * hash = NULL;
3136    unsigned int md_len;
3137    const EVP_MD *md = ssl_evp_md_fetch(s->ctx->libctx, NID_id_GostR3411_2012_256, s->ctx->propq);
3138
3139    if (md == NULL)
3140        return 0;
3141
3142    if ((hash = EVP_MD_CTX_new()) == NULL
3143        || EVP_DigestInit(hash, md) <= 0
3144        || EVP_DigestUpdate(hash, s->s3.client_random, SSL3_RANDOM_SIZE) <= 0
3145        || EVP_DigestUpdate(hash, s->s3.server_random, SSL3_RANDOM_SIZE) <= 0
3146        || EVP_DigestFinal_ex(hash, dgst_buf, &md_len) <= 0) {
3147        EVP_MD_CTX_free(hash);
3148        ssl_evp_md_free(md);
3149        return 0;
3150    }
3151
3152    EVP_MD_CTX_free(hash);
3153    ssl_evp_md_free(md);
3154    return 1;
3155}
3156#endif
3157
3158static int tls_construct_cke_gost18(SSL *s, WPACKET *pkt)
3159{
3160#ifndef OPENSSL_NO_GOST
3161    /* GOST 2018 key exchange message creation */
3162    unsigned char rnd_dgst[32];
3163    unsigned char *encdata = NULL;
3164    EVP_PKEY_CTX *pkey_ctx = NULL;
3165    X509 *peer_cert;
3166    unsigned char *pms = NULL;
3167    size_t pmslen = 0;
3168    size_t msglen;
3169    int cipher_nid = ossl_gost18_cke_cipher_nid(s);
3170
3171    if (cipher_nid == NID_undef) {
3172        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3173        return 0;
3174    }
3175
3176    if (ossl_gost_ukm(s, rnd_dgst) <= 0) {
3177        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3178        goto err;
3179    }
3180
3181    /* Pre-master secret - random bytes */
3182    pmslen = 32;
3183    pms = OPENSSL_malloc(pmslen);
3184    if (pms == NULL) {
3185        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3186        goto err;
3187    }
3188
3189    if (RAND_bytes_ex(s->ctx->libctx, pms, pmslen, 0) <= 0) {
3190        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3191        goto err;
3192    }
3193
3194     /* Get server certificate PKEY and create ctx from it */
3195    peer_cert = s->session->peer;
3196    if (peer_cert == NULL) {
3197        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3198                 SSL_R_NO_GOST_CERTIFICATE_SENT_BY_PEER);
3199        goto err;
3200    }
3201
3202    pkey_ctx = EVP_PKEY_CTX_new_from_pkey(s->ctx->libctx,
3203                                          X509_get0_pubkey(peer_cert),
3204                                          s->ctx->propq);
3205    if (pkey_ctx == NULL) {
3206        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3207        goto err;
3208    }
3209
3210    if (EVP_PKEY_encrypt_init(pkey_ctx) <= 0 ) {
3211        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3212        goto err;
3213    };
3214
3215    /* Reuse EVP_PKEY_CTRL_SET_IV, make choice in engine code */
3216    if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
3217                          EVP_PKEY_CTRL_SET_IV, 32, rnd_dgst) <= 0) {
3218        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
3219        goto err;
3220    }
3221
3222    if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
3223                          EVP_PKEY_CTRL_CIPHER, cipher_nid, NULL) <= 0) {
3224        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
3225        goto err;
3226    }
3227
3228    if (EVP_PKEY_encrypt(pkey_ctx, NULL, &msglen, pms, pmslen) <= 0) {
3229        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
3230        goto err;
3231    }
3232
3233    if (!WPACKET_allocate_bytes(pkt, msglen, &encdata)
3234            || EVP_PKEY_encrypt(pkey_ctx, encdata, &msglen, pms, pmslen) <= 0) {
3235        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
3236        goto err;
3237    }
3238
3239    EVP_PKEY_CTX_free(pkey_ctx);
3240    pkey_ctx = NULL;
3241    s->s3.tmp.pms = pms;
3242    s->s3.tmp.pmslen = pmslen;
3243
3244    return 1;
3245 err:
3246    EVP_PKEY_CTX_free(pkey_ctx);
3247    OPENSSL_clear_free(pms, pmslen);
3248    return 0;
3249#else
3250    SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3251    return 0;
3252#endif
3253}
3254
3255static int tls_construct_cke_srp(SSL *s, WPACKET *pkt)
3256{
3257#ifndef OPENSSL_NO_SRP
3258    unsigned char *abytes = NULL;
3259
3260    if (s->srp_ctx.A == NULL
3261            || !WPACKET_sub_allocate_bytes_u16(pkt, BN_num_bytes(s->srp_ctx.A),
3262                                               &abytes)) {
3263        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3264        return 0;
3265    }
3266    BN_bn2bin(s->srp_ctx.A, abytes);
3267
3268    OPENSSL_free(s->session->srp_username);
3269    s->session->srp_username = OPENSSL_strdup(s->srp_ctx.login);
3270    if (s->session->srp_username == NULL) {
3271        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3272        return 0;
3273    }
3274
3275    return 1;
3276#else
3277    SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3278    return 0;
3279#endif
3280}
3281
3282int tls_construct_client_key_exchange(SSL *s, WPACKET *pkt)
3283{
3284    unsigned long alg_k;
3285
3286    alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
3287
3288    /*
3289     * All of the construct functions below call SSLfatal() if necessary so
3290     * no need to do so here.
3291     */
3292    if ((alg_k & SSL_PSK)
3293        && !tls_construct_cke_psk_preamble(s, pkt))
3294        goto err;
3295
3296    if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) {
3297        if (!tls_construct_cke_rsa(s, pkt))
3298            goto err;
3299    } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
3300        if (!tls_construct_cke_dhe(s, pkt))
3301            goto err;
3302    } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
3303        if (!tls_construct_cke_ecdhe(s, pkt))
3304            goto err;
3305    } else if (alg_k & SSL_kGOST) {
3306        if (!tls_construct_cke_gost(s, pkt))
3307            goto err;
3308    } else if (alg_k & SSL_kGOST18) {
3309        if (!tls_construct_cke_gost18(s, pkt))
3310            goto err;
3311    } else if (alg_k & SSL_kSRP) {
3312        if (!tls_construct_cke_srp(s, pkt))
3313            goto err;
3314    } else if (!(alg_k & SSL_kPSK)) {
3315        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3316        goto err;
3317    }
3318
3319    return 1;
3320 err:
3321    OPENSSL_clear_free(s->s3.tmp.pms, s->s3.tmp.pmslen);
3322    s->s3.tmp.pms = NULL;
3323    s->s3.tmp.pmslen = 0;
3324#ifndef OPENSSL_NO_PSK
3325    OPENSSL_clear_free(s->s3.tmp.psk, s->s3.tmp.psklen);
3326    s->s3.tmp.psk = NULL;
3327    s->s3.tmp.psklen = 0;
3328#endif
3329    return 0;
3330}
3331
3332int tls_client_key_exchange_post_work(SSL *s)
3333{
3334    unsigned char *pms = NULL;
3335    size_t pmslen = 0;
3336
3337    pms = s->s3.tmp.pms;
3338    pmslen = s->s3.tmp.pmslen;
3339
3340#ifndef OPENSSL_NO_SRP
3341    /* Check for SRP */
3342    if (s->s3.tmp.new_cipher->algorithm_mkey & SSL_kSRP) {
3343        if (!srp_generate_client_master_secret(s)) {
3344            /* SSLfatal() already called */
3345            goto err;
3346        }
3347        return 1;
3348    }
3349#endif
3350
3351    if (pms == NULL && !(s->s3.tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
3352        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3353        goto err;
3354    }
3355    if (!ssl_generate_master_secret(s, pms, pmslen, 1)) {
3356        /* SSLfatal() already called */
3357        /* ssl_generate_master_secret frees the pms even on error */
3358        pms = NULL;
3359        pmslen = 0;
3360        goto err;
3361    }
3362    pms = NULL;
3363    pmslen = 0;
3364
3365#ifndef OPENSSL_NO_SCTP
3366    if (SSL_IS_DTLS(s)) {
3367        unsigned char sctpauthkey[64];
3368        char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
3369        size_t labellen;
3370
3371        /*
3372         * Add new shared key for SCTP-Auth, will be ignored if no SCTP
3373         * used.
3374         */
3375        memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
3376               sizeof(DTLS1_SCTP_AUTH_LABEL));
3377
3378        /* Don't include the terminating zero. */
3379        labellen = sizeof(labelbuffer) - 1;
3380        if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
3381            labellen += 1;
3382
3383        if (SSL_export_keying_material(s, sctpauthkey,
3384                                       sizeof(sctpauthkey), labelbuffer,
3385                                       labellen, NULL, 0, 0) <= 0) {
3386            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3387            goto err;
3388        }
3389
3390        BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
3391                 sizeof(sctpauthkey), sctpauthkey);
3392    }
3393#endif
3394
3395    return 1;
3396 err:
3397    OPENSSL_clear_free(pms, pmslen);
3398    s->s3.tmp.pms = NULL;
3399    s->s3.tmp.pmslen = 0;
3400    return 0;
3401}
3402
3403/*
3404 * Check a certificate can be used for client authentication. Currently check
3405 * cert exists, if we have a suitable digest for TLS 1.2 if static DH client
3406 * certificates can be used and optionally checks suitability for Suite B.
3407 */
3408static int ssl3_check_client_certificate(SSL *s)
3409{
3410    /* If no suitable signature algorithm can't use certificate */
3411    if (!tls_choose_sigalg(s, 0) || s->s3.tmp.sigalg == NULL)
3412        return 0;
3413    /*
3414     * If strict mode check suitability of chain before using it. This also
3415     * adjusts suite B digest if necessary.
3416     */
3417    if (s->cert->cert_flags & SSL_CERT_FLAGS_CHECK_TLS_STRICT &&
3418        !tls1_check_chain(s, NULL, NULL, NULL, -2))
3419        return 0;
3420    return 1;
3421}
3422
3423WORK_STATE tls_prepare_client_certificate(SSL *s, WORK_STATE wst)
3424{
3425    X509 *x509 = NULL;
3426    EVP_PKEY *pkey = NULL;
3427    int i;
3428
3429    if (wst == WORK_MORE_A) {
3430        /* Let cert callback update client certificates if required */
3431        if (s->cert->cert_cb) {
3432            i = s->cert->cert_cb(s, s->cert->cert_cb_arg);
3433            if (i < 0) {
3434                s->rwstate = SSL_X509_LOOKUP;
3435                return WORK_MORE_A;
3436            }
3437            if (i == 0) {
3438                SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_CALLBACK_FAILED);
3439                return WORK_ERROR;
3440            }
3441            s->rwstate = SSL_NOTHING;
3442        }
3443        if (ssl3_check_client_certificate(s)) {
3444            if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
3445                return WORK_FINISHED_STOP;
3446            }
3447            return WORK_FINISHED_CONTINUE;
3448        }
3449
3450        /* Fall through to WORK_MORE_B */
3451        wst = WORK_MORE_B;
3452    }
3453
3454    /* We need to get a client cert */
3455    if (wst == WORK_MORE_B) {
3456        /*
3457         * If we get an error, we need to ssl->rwstate=SSL_X509_LOOKUP;
3458         * return(-1); We then get retied later
3459         */
3460        i = ssl_do_client_cert_cb(s, &x509, &pkey);
3461        if (i < 0) {
3462            s->rwstate = SSL_X509_LOOKUP;
3463            return WORK_MORE_B;
3464        }
3465        s->rwstate = SSL_NOTHING;
3466        if ((i == 1) && (pkey != NULL) && (x509 != NULL)) {
3467            if (!SSL_use_certificate(s, x509) || !SSL_use_PrivateKey(s, pkey))
3468                i = 0;
3469        } else if (i == 1) {
3470            i = 0;
3471            ERR_raise(ERR_LIB_SSL, SSL_R_BAD_DATA_RETURNED_BY_CALLBACK);
3472        }
3473
3474        X509_free(x509);
3475        EVP_PKEY_free(pkey);
3476        if (i && !ssl3_check_client_certificate(s))
3477            i = 0;
3478        if (i == 0) {
3479            if (s->version == SSL3_VERSION) {
3480                s->s3.tmp.cert_req = 0;
3481                ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_CERTIFICATE);
3482                return WORK_FINISHED_CONTINUE;
3483            } else {
3484                s->s3.tmp.cert_req = 2;
3485                if (!ssl3_digest_cached_records(s, 0)) {
3486                    /* SSLfatal() already called */
3487                    return WORK_ERROR;
3488                }
3489            }
3490        }
3491
3492        if (s->post_handshake_auth == SSL_PHA_REQUESTED)
3493            return WORK_FINISHED_STOP;
3494        return WORK_FINISHED_CONTINUE;
3495    }
3496
3497    /* Shouldn't ever get here */
3498    SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3499    return WORK_ERROR;
3500}
3501
3502int tls_construct_client_certificate(SSL *s, WPACKET *pkt)
3503{
3504    if (SSL_IS_TLS13(s)) {
3505        if (s->pha_context == NULL) {
3506            /* no context available, add 0-length context */
3507            if (!WPACKET_put_bytes_u8(pkt, 0)) {
3508                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3509                return 0;
3510            }
3511        } else if (!WPACKET_sub_memcpy_u8(pkt, s->pha_context, s->pha_context_len)) {
3512            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3513            return 0;
3514        }
3515    }
3516    if (!ssl3_output_cert_chain(s, pkt,
3517                                (s->s3.tmp.cert_req == 2) ? NULL
3518                                                           : s->cert->key)) {
3519        /* SSLfatal() already called */
3520        return 0;
3521    }
3522
3523    if (SSL_IS_TLS13(s)
3524            && SSL_IS_FIRST_HANDSHAKE(s)
3525            && (!s->method->ssl3_enc->change_cipher_state(s,
3526                    SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_WRITE))) {
3527        /*
3528         * This is a fatal error, which leaves enc_write_ctx in an inconsistent
3529         * state and thus ssl3_send_alert may crash.
3530         */
3531        SSLfatal(s, SSL_AD_NO_ALERT, SSL_R_CANNOT_CHANGE_CIPHER);
3532        return 0;
3533    }
3534
3535    return 1;
3536}
3537
3538int ssl3_check_cert_and_algorithm(SSL *s)
3539{
3540    const SSL_CERT_LOOKUP *clu;
3541    size_t idx;
3542    long alg_k, alg_a;
3543
3544    alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
3545    alg_a = s->s3.tmp.new_cipher->algorithm_auth;
3546
3547    /* we don't have a certificate */
3548    if (!(alg_a & SSL_aCERT))
3549        return 1;
3550
3551    /* This is the passed certificate */
3552    clu = ssl_cert_lookup_by_pkey(X509_get0_pubkey(s->session->peer), &idx);
3553
3554    /* Check certificate is recognised and suitable for cipher */
3555    if (clu == NULL || (alg_a & clu->amask) == 0) {
3556        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_MISSING_SIGNING_CERT);
3557        return 0;
3558    }
3559
3560    if (clu->amask & SSL_aECDSA) {
3561        if (ssl_check_srvr_ecc_cert_and_alg(s->session->peer, s))
3562            return 1;
3563        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_BAD_ECC_CERT);
3564        return 0;
3565    }
3566
3567    if (alg_k & (SSL_kRSA | SSL_kRSAPSK) && idx != SSL_PKEY_RSA) {
3568        SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3569                 SSL_R_MISSING_RSA_ENCRYPTING_CERT);
3570        return 0;
3571    }
3572
3573    if ((alg_k & SSL_kDHE) && (s->s3.peer_tmp == NULL)) {
3574        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3575        return 0;
3576    }
3577
3578    return 1;
3579}
3580
3581#ifndef OPENSSL_NO_NEXTPROTONEG
3582int tls_construct_next_proto(SSL *s, WPACKET *pkt)
3583{
3584    size_t len, padding_len;
3585    unsigned char *padding = NULL;
3586
3587    len = s->ext.npn_len;
3588    padding_len = 32 - ((len + 2) % 32);
3589
3590    if (!WPACKET_sub_memcpy_u8(pkt, s->ext.npn, len)
3591            || !WPACKET_sub_allocate_bytes_u8(pkt, padding_len, &padding)) {
3592        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3593        return 0;
3594    }
3595
3596    memset(padding, 0, padding_len);
3597
3598    return 1;
3599}
3600#endif
3601
3602MSG_PROCESS_RETURN tls_process_hello_req(SSL *s, PACKET *pkt)
3603{
3604    if (PACKET_remaining(pkt) > 0) {
3605        /* should contain no data */
3606        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3607        return MSG_PROCESS_ERROR;
3608    }
3609
3610    if ((s->options & SSL_OP_NO_RENEGOTIATION)) {
3611        ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
3612        return MSG_PROCESS_FINISHED_READING;
3613    }
3614
3615    /*
3616     * This is a historical discrepancy (not in the RFC) maintained for
3617     * compatibility reasons. If a TLS client receives a HelloRequest it will
3618     * attempt an abbreviated handshake. However if a DTLS client receives a
3619     * HelloRequest it will do a full handshake. Either behaviour is reasonable
3620     * but doing one for TLS and another for DTLS is odd.
3621     */
3622    if (SSL_IS_DTLS(s))
3623        SSL_renegotiate(s);
3624    else
3625        SSL_renegotiate_abbreviated(s);
3626
3627    return MSG_PROCESS_FINISHED_READING;
3628}
3629
3630static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL *s, PACKET *pkt)
3631{
3632    PACKET extensions;
3633    RAW_EXTENSION *rawexts = NULL;
3634
3635    if (!PACKET_as_length_prefixed_2(pkt, &extensions)
3636            || PACKET_remaining(pkt) != 0) {
3637        SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3638        goto err;
3639    }
3640
3641    if (!tls_collect_extensions(s, &extensions,
3642                                SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS, &rawexts,
3643                                NULL, 1)
3644            || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
3645                                         rawexts, NULL, 0, 1)) {
3646        /* SSLfatal() already called */
3647        goto err;
3648    }
3649
3650    OPENSSL_free(rawexts);
3651    return MSG_PROCESS_CONTINUE_READING;
3652
3653 err:
3654    OPENSSL_free(rawexts);
3655    return MSG_PROCESS_ERROR;
3656}
3657
3658int ssl_do_client_cert_cb(SSL *s, X509 **px509, EVP_PKEY **ppkey)
3659{
3660    int i = 0;
3661#ifndef OPENSSL_NO_ENGINE
3662    if (s->ctx->client_cert_engine) {
3663        i = tls_engine_load_ssl_client_cert(s, px509, ppkey);
3664        if (i != 0)
3665            return i;
3666    }
3667#endif
3668    if (s->ctx->client_cert_cb)
3669        i = s->ctx->client_cert_cb(s, px509, ppkey);
3670    return i;
3671}
3672
3673int ssl_cipher_list_to_bytes(SSL *s, STACK_OF(SSL_CIPHER) *sk, WPACKET *pkt)
3674{
3675    int i;
3676    size_t totlen = 0, len, maxlen, maxverok = 0;
3677    int empty_reneg_info_scsv = !s->renegotiate;
3678
3679    /* Set disabled masks for this session */
3680    if (!ssl_set_client_disabled(s)) {
3681        SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_PROTOCOLS_AVAILABLE);
3682        return 0;
3683    }
3684
3685    if (sk == NULL) {
3686        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3687        return 0;
3688    }
3689
3690#ifdef OPENSSL_MAX_TLS1_2_CIPHER_LENGTH
3691# if OPENSSL_MAX_TLS1_2_CIPHER_LENGTH < 6
3692#  error Max cipher length too short
3693# endif
3694    /*
3695     * Some servers hang if client hello > 256 bytes as hack workaround
3696     * chop number of supported ciphers to keep it well below this if we
3697     * use TLS v1.2
3698     */
3699    if (TLS1_get_version(s) >= TLS1_2_VERSION)
3700        maxlen = OPENSSL_MAX_TLS1_2_CIPHER_LENGTH & ~1;
3701    else
3702#endif
3703        /* Maximum length that can be stored in 2 bytes. Length must be even */
3704        maxlen = 0xfffe;
3705
3706    if (empty_reneg_info_scsv)
3707        maxlen -= 2;
3708    if (s->mode & SSL_MODE_SEND_FALLBACK_SCSV)
3709        maxlen -= 2;
3710
3711    for (i = 0; i < sk_SSL_CIPHER_num(sk) && totlen < maxlen; i++) {
3712        const SSL_CIPHER *c;
3713
3714        c = sk_SSL_CIPHER_value(sk, i);
3715        /* Skip disabled ciphers */
3716        if (ssl_cipher_disabled(s, c, SSL_SECOP_CIPHER_SUPPORTED, 0))
3717            continue;
3718
3719        if (!s->method->put_cipher_by_char(c, pkt, &len)) {
3720            SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3721            return 0;
3722        }
3723
3724        /* Sanity check that the maximum version we offer has ciphers enabled */
3725        if (!maxverok) {
3726            if (SSL_IS_DTLS(s)) {
3727                if (DTLS_VERSION_GE(c->max_dtls, s->s3.tmp.max_ver)
3728                        && DTLS_VERSION_LE(c->min_dtls, s->s3.tmp.max_ver))
3729                    maxverok = 1;
3730            } else {
3731                if (c->max_tls >= s->s3.tmp.max_ver
3732                        && c->min_tls <= s->s3.tmp.max_ver)
3733                    maxverok = 1;
3734            }
3735        }
3736
3737        totlen += len;
3738    }
3739
3740    if (totlen == 0 || !maxverok) {
3741        const char *maxvertext =
3742            !maxverok
3743            ? "No ciphers enabled for max supported SSL/TLS version"
3744            : NULL;
3745
3746        SSLfatal_data(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_CIPHERS_AVAILABLE,
3747                      maxvertext);
3748        return 0;
3749    }
3750
3751    if (totlen != 0) {
3752        if (empty_reneg_info_scsv) {
3753            static SSL_CIPHER scsv = {
3754                0, NULL, NULL, SSL3_CK_SCSV, 0, 0, 0, 0, 0, 0, 0, 0, 0
3755            };
3756            if (!s->method->put_cipher_by_char(&scsv, pkt, &len)) {
3757                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3758                return 0;
3759            }
3760        }
3761        if (s->mode & SSL_MODE_SEND_FALLBACK_SCSV) {
3762            static SSL_CIPHER scsv = {
3763                0, NULL, NULL, SSL3_CK_FALLBACK_SCSV, 0, 0, 0, 0, 0, 0, 0, 0, 0
3764            };
3765            if (!s->method->put_cipher_by_char(&scsv, pkt, &len)) {
3766                SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3767                return 0;
3768            }
3769        }
3770    }
3771
3772    return 1;
3773}
3774
3775int tls_construct_end_of_early_data(SSL *s, WPACKET *pkt)
3776{
3777    if (s->early_data_state != SSL_EARLY_DATA_WRITE_RETRY
3778            && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING) {
3779        SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
3780        return 0;
3781    }
3782
3783    s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
3784    return 1;
3785}
3786