xref: /freebsd/crypto/openssl/ssl/statem/statem_srvr.c (revision 44096ebd22ddd0081a357011714eff8963614b65)
1 /*
2  * Copyright 1995-2024 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 "../ssl_local.h"
14 #include "statem_local.h"
15 #include "internal/constant_time.h"
16 #include "internal/cryptlib.h"
17 #include <openssl/buffer.h>
18 #include <openssl/rand.h>
19 #include <openssl/objects.h>
20 #include <openssl/evp.h>
21 #include <openssl/x509.h>
22 #include <openssl/dh.h>
23 #include <openssl/rsa.h>
24 #include <openssl/bn.h>
25 #include <openssl/md5.h>
26 #include <openssl/trace.h>
27 #include <openssl/core_names.h>
28 #include <openssl/asn1t.h>
29 
30 #define TICKET_NONCE_SIZE       8
31 
32 typedef struct {
33   ASN1_TYPE *kxBlob;
34   ASN1_TYPE *opaqueBlob;
35 } GOST_KX_MESSAGE;
36 
37 DECLARE_ASN1_FUNCTIONS(GOST_KX_MESSAGE)
38 
39 ASN1_SEQUENCE(GOST_KX_MESSAGE) = {
40   ASN1_SIMPLE(GOST_KX_MESSAGE,  kxBlob, ASN1_ANY),
41   ASN1_OPT(GOST_KX_MESSAGE, opaqueBlob, ASN1_ANY),
42 } ASN1_SEQUENCE_END(GOST_KX_MESSAGE)
43 
44 IMPLEMENT_ASN1_FUNCTIONS(GOST_KX_MESSAGE)
45 
46 static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt);
47 
48 /*
49  * ossl_statem_server13_read_transition() encapsulates the logic for the allowed
50  * handshake state transitions when a TLSv1.3 server is reading messages from
51  * the client. The message type that the client has sent is provided in |mt|.
52  * The current state is in |s->statem.hand_state|.
53  *
54  * Return values are 1 for success (transition allowed) and  0 on error
55  * (transition not allowed)
56  */
57 static int ossl_statem_server13_read_transition(SSL *s, int mt)
58 {
59     OSSL_STATEM *st = &s->statem;
60 
61     /*
62      * Note: There is no case for TLS_ST_BEFORE because at that stage we have
63      * not negotiated TLSv1.3 yet, so that case is handled by
64      * ossl_statem_server_read_transition()
65      */
66     switch (st->hand_state) {
67     default:
68         break;
69 
70     case TLS_ST_EARLY_DATA:
71         if (s->hello_retry_request == SSL_HRR_PENDING) {
72             if (mt == SSL3_MT_CLIENT_HELLO) {
73                 st->hand_state = TLS_ST_SR_CLNT_HELLO;
74                 return 1;
75             }
76             break;
77         } else if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED) {
78             if (mt == SSL3_MT_END_OF_EARLY_DATA) {
79                 st->hand_state = TLS_ST_SR_END_OF_EARLY_DATA;
80                 return 1;
81             }
82             break;
83         }
84         /* Fall through */
85 
86     case TLS_ST_SR_END_OF_EARLY_DATA:
87     case TLS_ST_SW_FINISHED:
88         if (s->s3.tmp.cert_request) {
89             if (mt == SSL3_MT_CERTIFICATE) {
90                 st->hand_state = TLS_ST_SR_CERT;
91                 return 1;
92             }
93         } else {
94             if (mt == SSL3_MT_FINISHED) {
95                 st->hand_state = TLS_ST_SR_FINISHED;
96                 return 1;
97             }
98         }
99         break;
100 
101     case TLS_ST_SR_CERT:
102         if (s->session->peer == NULL) {
103             if (mt == SSL3_MT_FINISHED) {
104                 st->hand_state = TLS_ST_SR_FINISHED;
105                 return 1;
106             }
107         } else {
108             if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
109                 st->hand_state = TLS_ST_SR_CERT_VRFY;
110                 return 1;
111             }
112         }
113         break;
114 
115     case TLS_ST_SR_CERT_VRFY:
116         if (mt == SSL3_MT_FINISHED) {
117             st->hand_state = TLS_ST_SR_FINISHED;
118             return 1;
119         }
120         break;
121 
122     case TLS_ST_OK:
123         /*
124          * Its never ok to start processing handshake messages in the middle of
125          * early data (i.e. before we've received the end of early data alert)
126          */
127         if (s->early_data_state == SSL_EARLY_DATA_READING)
128             break;
129 
130         if (mt == SSL3_MT_CERTIFICATE
131                 && s->post_handshake_auth == SSL_PHA_REQUESTED) {
132             st->hand_state = TLS_ST_SR_CERT;
133             return 1;
134         }
135 
136         if (mt == SSL3_MT_KEY_UPDATE) {
137             st->hand_state = TLS_ST_SR_KEY_UPDATE;
138             return 1;
139         }
140         break;
141     }
142 
143     /* No valid transition found */
144     return 0;
145 }
146 
147 /*
148  * ossl_statem_server_read_transition() encapsulates the logic for the allowed
149  * handshake state transitions when the server is reading messages from the
150  * client. The message type that the client has sent is provided in |mt|. The
151  * current state is in |s->statem.hand_state|.
152  *
153  * Return values are 1 for success (transition allowed) and  0 on error
154  * (transition not allowed)
155  */
156 int ossl_statem_server_read_transition(SSL *s, int mt)
157 {
158     OSSL_STATEM *st = &s->statem;
159 
160     if (SSL_IS_TLS13(s)) {
161         if (!ossl_statem_server13_read_transition(s, mt))
162             goto err;
163         return 1;
164     }
165 
166     switch (st->hand_state) {
167     default:
168         break;
169 
170     case TLS_ST_BEFORE:
171     case TLS_ST_OK:
172     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
173         if (mt == SSL3_MT_CLIENT_HELLO) {
174             st->hand_state = TLS_ST_SR_CLNT_HELLO;
175             return 1;
176         }
177         break;
178 
179     case TLS_ST_SW_SRVR_DONE:
180         /*
181          * If we get a CKE message after a ServerDone then either
182          * 1) We didn't request a Certificate
183          * OR
184          * 2) If we did request one then
185          *      a) We allow no Certificate to be returned
186          *      AND
187          *      b) We are running SSL3 (in TLS1.0+ the client must return a 0
188          *         list if we requested a certificate)
189          */
190         if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) {
191             if (s->s3.tmp.cert_request) {
192                 if (s->version == SSL3_VERSION) {
193                     if ((s->verify_mode & SSL_VERIFY_PEER)
194                         && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) {
195                         /*
196                          * This isn't an unexpected message as such - we're just
197                          * not going to accept it because we require a client
198                          * cert.
199                          */
200                         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
201                                  SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
202                         return 0;
203                     }
204                     st->hand_state = TLS_ST_SR_KEY_EXCH;
205                     return 1;
206                 }
207             } else {
208                 st->hand_state = TLS_ST_SR_KEY_EXCH;
209                 return 1;
210             }
211         } else if (s->s3.tmp.cert_request) {
212             if (mt == SSL3_MT_CERTIFICATE) {
213                 st->hand_state = TLS_ST_SR_CERT;
214                 return 1;
215             }
216         }
217         break;
218 
219     case TLS_ST_SR_CERT:
220         if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) {
221             st->hand_state = TLS_ST_SR_KEY_EXCH;
222             return 1;
223         }
224         break;
225 
226     case TLS_ST_SR_KEY_EXCH:
227         /*
228          * We should only process a CertificateVerify message if we have
229          * received a Certificate from the client. If so then |s->session->peer|
230          * will be non NULL. In some instances a CertificateVerify message is
231          * not required even if the peer has sent a Certificate (e.g. such as in
232          * the case of static DH). In that case |st->no_cert_verify| should be
233          * set.
234          */
235         if (s->session->peer == NULL || st->no_cert_verify) {
236             if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
237                 /*
238                  * For the ECDH ciphersuites when the client sends its ECDH
239                  * pub key in a certificate, the CertificateVerify message is
240                  * not sent. Also for GOST ciphersuites when the client uses
241                  * its key from the certificate for key exchange.
242                  */
243                 st->hand_state = TLS_ST_SR_CHANGE;
244                 return 1;
245             }
246         } else {
247             if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
248                 st->hand_state = TLS_ST_SR_CERT_VRFY;
249                 return 1;
250             }
251         }
252         break;
253 
254     case TLS_ST_SR_CERT_VRFY:
255         if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
256             st->hand_state = TLS_ST_SR_CHANGE;
257             return 1;
258         }
259         break;
260 
261     case TLS_ST_SR_CHANGE:
262 #ifndef OPENSSL_NO_NEXTPROTONEG
263         if (s->s3.npn_seen) {
264             if (mt == SSL3_MT_NEXT_PROTO) {
265                 st->hand_state = TLS_ST_SR_NEXT_PROTO;
266                 return 1;
267             }
268         } else {
269 #endif
270             if (mt == SSL3_MT_FINISHED) {
271                 st->hand_state = TLS_ST_SR_FINISHED;
272                 return 1;
273             }
274 #ifndef OPENSSL_NO_NEXTPROTONEG
275         }
276 #endif
277         break;
278 
279 #ifndef OPENSSL_NO_NEXTPROTONEG
280     case TLS_ST_SR_NEXT_PROTO:
281         if (mt == SSL3_MT_FINISHED) {
282             st->hand_state = TLS_ST_SR_FINISHED;
283             return 1;
284         }
285         break;
286 #endif
287 
288     case TLS_ST_SW_FINISHED:
289         if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
290             st->hand_state = TLS_ST_SR_CHANGE;
291             return 1;
292         }
293         break;
294     }
295 
296  err:
297     /* No valid transition found */
298     if (SSL_IS_DTLS(s) && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
299         BIO *rbio;
300 
301         /*
302          * CCS messages don't have a message sequence number so this is probably
303          * because of an out-of-order CCS. We'll just drop it.
304          */
305         s->init_num = 0;
306         s->rwstate = SSL_READING;
307         rbio = SSL_get_rbio(s);
308         BIO_clear_retry_flags(rbio);
309         BIO_set_retry_read(rbio);
310         return 0;
311     }
312     SSLfatal(s, SSL3_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
313     return 0;
314 }
315 
316 /*
317  * Should we send a ServerKeyExchange message?
318  *
319  * Valid return values are:
320  *   1: Yes
321  *   0: No
322  */
323 static int send_server_key_exchange(SSL *s)
324 {
325     unsigned long alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
326 
327     /*
328      * only send a ServerKeyExchange if DH or fortezza but we have a
329      * sign only certificate PSK: may send PSK identity hints For
330      * ECC ciphersuites, we send a serverKeyExchange message only if
331      * the cipher suite is either ECDH-anon or ECDHE. In other cases,
332      * the server certificate contains the server's public key for
333      * key exchange.
334      */
335     if (alg_k & (SSL_kDHE | SSL_kECDHE)
336         /*
337          * PSK: send ServerKeyExchange if PSK identity hint if
338          * provided
339          */
340 #ifndef OPENSSL_NO_PSK
341         /* Only send SKE if we have identity hint for plain PSK */
342         || ((alg_k & (SSL_kPSK | SSL_kRSAPSK))
343             && s->cert->psk_identity_hint)
344         /* For other PSK always send SKE */
345         || (alg_k & (SSL_PSK & (SSL_kDHEPSK | SSL_kECDHEPSK)))
346 #endif
347 #ifndef OPENSSL_NO_SRP
348         /* SRP: send ServerKeyExchange */
349         || (alg_k & SSL_kSRP)
350 #endif
351         ) {
352         return 1;
353     }
354 
355     return 0;
356 }
357 
358 /*
359  * Should we send a CertificateRequest message?
360  *
361  * Valid return values are:
362  *   1: Yes
363  *   0: No
364  */
365 int send_certificate_request(SSL *s)
366 {
367     if (
368            /* don't request cert unless asked for it: */
369            s->verify_mode & SSL_VERIFY_PEER
370            /*
371             * don't request if post-handshake-only unless doing
372             * post-handshake in TLSv1.3:
373             */
374            && (!SSL_IS_TLS13(s) || !(s->verify_mode & SSL_VERIFY_POST_HANDSHAKE)
375                || s->post_handshake_auth == SSL_PHA_REQUEST_PENDING)
376            /*
377             * if SSL_VERIFY_CLIENT_ONCE is set, don't request cert
378             * a second time:
379             */
380            && (s->certreqs_sent < 1 ||
381                !(s->verify_mode & SSL_VERIFY_CLIENT_ONCE))
382            /*
383             * never request cert in anonymous ciphersuites (see
384             * section "Certificate request" in SSL 3 drafts and in
385             * RFC 2246):
386             */
387            && (!(s->s3.tmp.new_cipher->algorithm_auth & SSL_aNULL)
388                /*
389                 * ... except when the application insists on
390                 * verification (against the specs, but statem_clnt.c accepts
391                 * this for SSL 3)
392                 */
393                || (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))
394            /* don't request certificate for SRP auth */
395            && !(s->s3.tmp.new_cipher->algorithm_auth & SSL_aSRP)
396            /*
397             * With normal PSK Certificates and Certificate Requests
398             * are omitted
399             */
400            && !(s->s3.tmp.new_cipher->algorithm_auth & SSL_aPSK)) {
401         return 1;
402     }
403 
404     return 0;
405 }
406 
407 /*
408  * ossl_statem_server13_write_transition() works out what handshake state to
409  * move to next when a TLSv1.3 server is writing messages to be sent to the
410  * client.
411  */
412 static WRITE_TRAN ossl_statem_server13_write_transition(SSL *s)
413 {
414     OSSL_STATEM *st = &s->statem;
415 
416     /*
417      * No case for TLS_ST_BEFORE, because at that stage we have not negotiated
418      * TLSv1.3 yet, so that is handled by ossl_statem_server_write_transition()
419      */
420 
421     switch (st->hand_state) {
422     default:
423         /* Shouldn't happen */
424         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
425         return WRITE_TRAN_ERROR;
426 
427     case TLS_ST_OK:
428         if (s->key_update != SSL_KEY_UPDATE_NONE) {
429             st->hand_state = TLS_ST_SW_KEY_UPDATE;
430             return WRITE_TRAN_CONTINUE;
431         }
432         if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
433             st->hand_state = TLS_ST_SW_CERT_REQ;
434             return WRITE_TRAN_CONTINUE;
435         }
436         if (s->ext.extra_tickets_expected > 0) {
437             st->hand_state = TLS_ST_SW_SESSION_TICKET;
438             return WRITE_TRAN_CONTINUE;
439         }
440         /* Try to read from the client instead */
441         return WRITE_TRAN_FINISHED;
442 
443     case TLS_ST_SR_CLNT_HELLO:
444         st->hand_state = TLS_ST_SW_SRVR_HELLO;
445         return WRITE_TRAN_CONTINUE;
446 
447     case TLS_ST_SW_SRVR_HELLO:
448         if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
449                 && s->hello_retry_request != SSL_HRR_COMPLETE)
450             st->hand_state = TLS_ST_SW_CHANGE;
451         else if (s->hello_retry_request == SSL_HRR_PENDING)
452             st->hand_state = TLS_ST_EARLY_DATA;
453         else
454             st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS;
455         return WRITE_TRAN_CONTINUE;
456 
457     case TLS_ST_SW_CHANGE:
458         if (s->hello_retry_request == SSL_HRR_PENDING)
459             st->hand_state = TLS_ST_EARLY_DATA;
460         else
461             st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS;
462         return WRITE_TRAN_CONTINUE;
463 
464     case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
465         if (s->hit)
466             st->hand_state = TLS_ST_SW_FINISHED;
467         else if (send_certificate_request(s))
468             st->hand_state = TLS_ST_SW_CERT_REQ;
469         else
470             st->hand_state = TLS_ST_SW_CERT;
471 
472         return WRITE_TRAN_CONTINUE;
473 
474     case TLS_ST_SW_CERT_REQ:
475         if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
476             s->post_handshake_auth = SSL_PHA_REQUESTED;
477             st->hand_state = TLS_ST_OK;
478         } else {
479             st->hand_state = TLS_ST_SW_CERT;
480         }
481         return WRITE_TRAN_CONTINUE;
482 
483     case TLS_ST_SW_CERT:
484         st->hand_state = TLS_ST_SW_CERT_VRFY;
485         return WRITE_TRAN_CONTINUE;
486 
487     case TLS_ST_SW_CERT_VRFY:
488         st->hand_state = TLS_ST_SW_FINISHED;
489         return WRITE_TRAN_CONTINUE;
490 
491     case TLS_ST_SW_FINISHED:
492         st->hand_state = TLS_ST_EARLY_DATA;
493         return WRITE_TRAN_CONTINUE;
494 
495     case TLS_ST_EARLY_DATA:
496         return WRITE_TRAN_FINISHED;
497 
498     case TLS_ST_SR_FINISHED:
499         /*
500          * Technically we have finished the handshake at this point, but we're
501          * going to remain "in_init" for now and write out any session tickets
502          * immediately.
503          */
504         if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
505             s->post_handshake_auth = SSL_PHA_EXT_RECEIVED;
506         } else if (!s->ext.ticket_expected) {
507             /*
508              * If we're not going to renew the ticket then we just finish the
509              * handshake at this point.
510              */
511             st->hand_state = TLS_ST_OK;
512             return WRITE_TRAN_CONTINUE;
513         }
514         if (s->num_tickets > s->sent_tickets)
515             st->hand_state = TLS_ST_SW_SESSION_TICKET;
516         else
517             st->hand_state = TLS_ST_OK;
518         return WRITE_TRAN_CONTINUE;
519 
520     case TLS_ST_SR_KEY_UPDATE:
521     case TLS_ST_SW_KEY_UPDATE:
522         st->hand_state = TLS_ST_OK;
523         return WRITE_TRAN_CONTINUE;
524 
525     case TLS_ST_SW_SESSION_TICKET:
526         /* In a resumption we only ever send a maximum of one new ticket.
527          * Following an initial handshake we send the number of tickets we have
528          * been configured for.
529          */
530         if (!SSL_IS_FIRST_HANDSHAKE(s) && s->ext.extra_tickets_expected > 0) {
531             return WRITE_TRAN_CONTINUE;
532         } else if (s->hit || s->num_tickets <= s->sent_tickets) {
533             /* We've written enough tickets out. */
534             st->hand_state = TLS_ST_OK;
535         }
536         return WRITE_TRAN_CONTINUE;
537     }
538 }
539 
540 /*
541  * ossl_statem_server_write_transition() works out what handshake state to move
542  * to next when the server is writing messages to be sent to the client.
543  */
544 WRITE_TRAN ossl_statem_server_write_transition(SSL *s)
545 {
546     OSSL_STATEM *st = &s->statem;
547 
548     /*
549      * Note that before the ClientHello we don't know what version we are going
550      * to negotiate yet, so we don't take this branch until later
551      */
552 
553     if (SSL_IS_TLS13(s))
554         return ossl_statem_server13_write_transition(s);
555 
556     switch (st->hand_state) {
557     default:
558         /* Shouldn't happen */
559         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
560         return WRITE_TRAN_ERROR;
561 
562     case TLS_ST_OK:
563         if (st->request_state == TLS_ST_SW_HELLO_REQ) {
564             /* We must be trying to renegotiate */
565             st->hand_state = TLS_ST_SW_HELLO_REQ;
566             st->request_state = TLS_ST_BEFORE;
567             return WRITE_TRAN_CONTINUE;
568         }
569         /* Must be an incoming ClientHello */
570         if (!tls_setup_handshake(s)) {
571             /* SSLfatal() already called */
572             return WRITE_TRAN_ERROR;
573         }
574         /* Fall through */
575 
576     case TLS_ST_BEFORE:
577         /* Just go straight to trying to read from the client */
578         return WRITE_TRAN_FINISHED;
579 
580     case TLS_ST_SW_HELLO_REQ:
581         st->hand_state = TLS_ST_OK;
582         return WRITE_TRAN_CONTINUE;
583 
584     case TLS_ST_SR_CLNT_HELLO:
585         if (SSL_IS_DTLS(s) && !s->d1->cookie_verified
586             && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)) {
587             st->hand_state = DTLS_ST_SW_HELLO_VERIFY_REQUEST;
588         } else if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) {
589             /* We must have rejected the renegotiation */
590             st->hand_state = TLS_ST_OK;
591             return WRITE_TRAN_CONTINUE;
592         } else {
593             st->hand_state = TLS_ST_SW_SRVR_HELLO;
594         }
595         return WRITE_TRAN_CONTINUE;
596 
597     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
598         return WRITE_TRAN_FINISHED;
599 
600     case TLS_ST_SW_SRVR_HELLO:
601         if (s->hit) {
602             if (s->ext.ticket_expected)
603                 st->hand_state = TLS_ST_SW_SESSION_TICKET;
604             else
605                 st->hand_state = TLS_ST_SW_CHANGE;
606         } else {
607             /* Check if it is anon DH or anon ECDH, */
608             /* normal PSK or SRP */
609             if (!(s->s3.tmp.new_cipher->algorithm_auth &
610                   (SSL_aNULL | SSL_aSRP | SSL_aPSK))) {
611                 st->hand_state = TLS_ST_SW_CERT;
612             } else if (send_server_key_exchange(s)) {
613                 st->hand_state = TLS_ST_SW_KEY_EXCH;
614             } else if (send_certificate_request(s)) {
615                 st->hand_state = TLS_ST_SW_CERT_REQ;
616             } else {
617                 st->hand_state = TLS_ST_SW_SRVR_DONE;
618             }
619         }
620         return WRITE_TRAN_CONTINUE;
621 
622     case TLS_ST_SW_CERT:
623         if (s->ext.status_expected) {
624             st->hand_state = TLS_ST_SW_CERT_STATUS;
625             return WRITE_TRAN_CONTINUE;
626         }
627         /* Fall through */
628 
629     case TLS_ST_SW_CERT_STATUS:
630         if (send_server_key_exchange(s)) {
631             st->hand_state = TLS_ST_SW_KEY_EXCH;
632             return WRITE_TRAN_CONTINUE;
633         }
634         /* Fall through */
635 
636     case TLS_ST_SW_KEY_EXCH:
637         if (send_certificate_request(s)) {
638             st->hand_state = TLS_ST_SW_CERT_REQ;
639             return WRITE_TRAN_CONTINUE;
640         }
641         /* Fall through */
642 
643     case TLS_ST_SW_CERT_REQ:
644         st->hand_state = TLS_ST_SW_SRVR_DONE;
645         return WRITE_TRAN_CONTINUE;
646 
647     case TLS_ST_SW_SRVR_DONE:
648         return WRITE_TRAN_FINISHED;
649 
650     case TLS_ST_SR_FINISHED:
651         if (s->hit) {
652             st->hand_state = TLS_ST_OK;
653             return WRITE_TRAN_CONTINUE;
654         } else if (s->ext.ticket_expected) {
655             st->hand_state = TLS_ST_SW_SESSION_TICKET;
656         } else {
657             st->hand_state = TLS_ST_SW_CHANGE;
658         }
659         return WRITE_TRAN_CONTINUE;
660 
661     case TLS_ST_SW_SESSION_TICKET:
662         st->hand_state = TLS_ST_SW_CHANGE;
663         return WRITE_TRAN_CONTINUE;
664 
665     case TLS_ST_SW_CHANGE:
666         st->hand_state = TLS_ST_SW_FINISHED;
667         return WRITE_TRAN_CONTINUE;
668 
669     case TLS_ST_SW_FINISHED:
670         if (s->hit) {
671             return WRITE_TRAN_FINISHED;
672         }
673         st->hand_state = TLS_ST_OK;
674         return WRITE_TRAN_CONTINUE;
675     }
676 }
677 
678 /*
679  * Perform any pre work that needs to be done prior to sending a message from
680  * the server to the client.
681  */
682 WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst)
683 {
684     OSSL_STATEM *st = &s->statem;
685 
686     switch (st->hand_state) {
687     default:
688         /* No pre work to be done */
689         break;
690 
691     case TLS_ST_SW_HELLO_REQ:
692         s->shutdown = 0;
693         if (SSL_IS_DTLS(s))
694             dtls1_clear_sent_buffer(s);
695         break;
696 
697     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
698         s->shutdown = 0;
699         if (SSL_IS_DTLS(s)) {
700             dtls1_clear_sent_buffer(s);
701             /* We don't buffer this message so don't use the timer */
702             st->use_timer = 0;
703         }
704         break;
705 
706     case TLS_ST_SW_SRVR_HELLO:
707         if (SSL_IS_DTLS(s)) {
708             /*
709              * Messages we write from now on should be buffered and
710              * retransmitted if necessary, so we need to use the timer now
711              */
712             st->use_timer = 1;
713         }
714         break;
715 
716     case TLS_ST_SW_SRVR_DONE:
717 #ifndef OPENSSL_NO_SCTP
718         if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
719             /* Calls SSLfatal() as required */
720             return dtls_wait_for_dry(s);
721         }
722 #endif
723         return WORK_FINISHED_CONTINUE;
724 
725     case TLS_ST_SW_SESSION_TICKET:
726         if (SSL_IS_TLS13(s) && s->sent_tickets == 0
727                 && s->ext.extra_tickets_expected == 0) {
728             /*
729              * Actually this is the end of the handshake, but we're going
730              * straight into writing the session ticket out. So we finish off
731              * the handshake, but keep the various buffers active.
732              *
733              * Calls SSLfatal as required.
734              */
735             return tls_finish_handshake(s, wst, 0, 0);
736         }
737         if (SSL_IS_DTLS(s)) {
738             /*
739              * We're into the last flight. We don't retransmit the last flight
740              * unless we need to, so we don't use the timer
741              */
742             st->use_timer = 0;
743         }
744         break;
745 
746     case TLS_ST_SW_CHANGE:
747         if (SSL_IS_TLS13(s))
748             break;
749         /* Writes to s->session are only safe for initial handshakes */
750         if (s->session->cipher == NULL) {
751             s->session->cipher = s->s3.tmp.new_cipher;
752         } else if (s->session->cipher != s->s3.tmp.new_cipher) {
753             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
754             return WORK_ERROR;
755         }
756         if (!s->method->ssl3_enc->setup_key_block(s)) {
757             /* SSLfatal() already called */
758             return WORK_ERROR;
759         }
760         if (SSL_IS_DTLS(s)) {
761             /*
762              * We're into the last flight. We don't retransmit the last flight
763              * unless we need to, so we don't use the timer. This might have
764              * already been set to 0 if we sent a NewSessionTicket message,
765              * but we'll set it again here in case we didn't.
766              */
767             st->use_timer = 0;
768         }
769         return WORK_FINISHED_CONTINUE;
770 
771     case TLS_ST_EARLY_DATA:
772         if (s->early_data_state != SSL_EARLY_DATA_ACCEPTING
773                 && (s->s3.flags & TLS1_FLAGS_STATELESS) == 0)
774             return WORK_FINISHED_CONTINUE;
775         /* Fall through */
776 
777     case TLS_ST_OK:
778         /* Calls SSLfatal() as required */
779         return tls_finish_handshake(s, wst, 1, 1);
780     }
781 
782     return WORK_FINISHED_CONTINUE;
783 }
784 
785 static ossl_inline int conn_is_closed(void)
786 {
787     switch (get_last_sys_error()) {
788 #if defined(EPIPE)
789     case EPIPE:
790         return 1;
791 #endif
792 #if defined(ECONNRESET)
793     case ECONNRESET:
794         return 1;
795 #endif
796 #if defined(WSAECONNRESET)
797     case WSAECONNRESET:
798         return 1;
799 #endif
800     default:
801         return 0;
802     }
803 }
804 
805 /*
806  * Perform any work that needs to be done after sending a message from the
807  * server to the client.
808  */
809 WORK_STATE ossl_statem_server_post_work(SSL *s, WORK_STATE wst)
810 {
811     OSSL_STATEM *st = &s->statem;
812 
813     s->init_num = 0;
814 
815     switch (st->hand_state) {
816     default:
817         /* No post work to be done */
818         break;
819 
820     case TLS_ST_SW_HELLO_REQ:
821         if (statem_flush(s) != 1)
822             return WORK_MORE_A;
823         if (!ssl3_init_finished_mac(s)) {
824             /* SSLfatal() already called */
825             return WORK_ERROR;
826         }
827         break;
828 
829     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
830         if (statem_flush(s) != 1)
831             return WORK_MORE_A;
832         /* HelloVerifyRequest resets Finished MAC */
833         if (s->version != DTLS1_BAD_VER && !ssl3_init_finished_mac(s)) {
834             /* SSLfatal() already called */
835             return WORK_ERROR;
836         }
837         /*
838          * The next message should be another ClientHello which we need to
839          * treat like it was the first packet
840          */
841         s->first_packet = 1;
842         break;
843 
844     case TLS_ST_SW_SRVR_HELLO:
845         if (SSL_IS_TLS13(s) && s->hello_retry_request == SSL_HRR_PENDING) {
846             if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) == 0
847                     && statem_flush(s) != 1)
848                 return WORK_MORE_A;
849             break;
850         }
851 #ifndef OPENSSL_NO_SCTP
852         if (SSL_IS_DTLS(s) && s->hit) {
853             unsigned char sctpauthkey[64];
854             char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
855             size_t labellen;
856 
857             /*
858              * Add new shared key for SCTP-Auth, will be ignored if no
859              * SCTP used.
860              */
861             memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
862                    sizeof(DTLS1_SCTP_AUTH_LABEL));
863 
864             /* Don't include the terminating zero. */
865             labellen = sizeof(labelbuffer) - 1;
866             if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
867                 labellen += 1;
868 
869             if (SSL_export_keying_material(s, sctpauthkey,
870                                            sizeof(sctpauthkey), labelbuffer,
871                                            labellen, NULL, 0,
872                                            0) <= 0) {
873                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
874                 return WORK_ERROR;
875             }
876 
877             BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
878                      sizeof(sctpauthkey), sctpauthkey);
879         }
880 #endif
881         if (!SSL_IS_TLS13(s)
882                 || ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
883                     && s->hello_retry_request != SSL_HRR_COMPLETE))
884             break;
885         /* Fall through */
886 
887     case TLS_ST_SW_CHANGE:
888         if (s->hello_retry_request == SSL_HRR_PENDING) {
889             if (!statem_flush(s))
890                 return WORK_MORE_A;
891             break;
892         }
893 
894         if (SSL_IS_TLS13(s)) {
895             if (!s->method->ssl3_enc->setup_key_block(s)
896                 || !s->method->ssl3_enc->change_cipher_state(s,
897                         SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_WRITE)) {
898                 /* SSLfatal() already called */
899                 return WORK_ERROR;
900             }
901 
902             if (s->ext.early_data != SSL_EARLY_DATA_ACCEPTED
903                 && !s->method->ssl3_enc->change_cipher_state(s,
904                         SSL3_CC_HANDSHAKE |SSL3_CHANGE_CIPHER_SERVER_READ)) {
905                 /* SSLfatal() already called */
906                 return WORK_ERROR;
907             }
908             /*
909              * We don't yet know whether the next record we are going to receive
910              * is an unencrypted alert, an encrypted alert, or an encrypted
911              * handshake message. We temporarily tolerate unencrypted alerts.
912              */
913             s->statem.enc_read_state = ENC_READ_STATE_ALLOW_PLAIN_ALERTS;
914             break;
915         }
916 
917 #ifndef OPENSSL_NO_SCTP
918         if (SSL_IS_DTLS(s) && !s->hit) {
919             /*
920              * Change to new shared key of SCTP-Auth, will be ignored if
921              * no SCTP used.
922              */
923             BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
924                      0, NULL);
925         }
926 #endif
927         if (!s->method->ssl3_enc->change_cipher_state(s,
928                                                       SSL3_CHANGE_CIPHER_SERVER_WRITE))
929         {
930             /* SSLfatal() already called */
931             return WORK_ERROR;
932         }
933 
934         if (SSL_IS_DTLS(s))
935             dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
936         break;
937 
938     case TLS_ST_SW_SRVR_DONE:
939         if (statem_flush(s) != 1)
940             return WORK_MORE_A;
941         break;
942 
943     case TLS_ST_SW_FINISHED:
944         if (statem_flush(s) != 1)
945             return WORK_MORE_A;
946 #ifndef OPENSSL_NO_SCTP
947         if (SSL_IS_DTLS(s) && s->hit) {
948             /*
949              * Change to new shared key of SCTP-Auth, will be ignored if
950              * no SCTP used.
951              */
952             BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
953                      0, NULL);
954         }
955 #endif
956         if (SSL_IS_TLS13(s)) {
957             /* TLS 1.3 gets the secret size from the handshake md */
958             size_t dummy;
959             if (!s->method->ssl3_enc->generate_master_secret(s,
960                         s->master_secret, s->handshake_secret, 0,
961                         &dummy)
962                 || !s->method->ssl3_enc->change_cipher_state(s,
963                         SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_SERVER_WRITE))
964             /* SSLfatal() already called */
965             return WORK_ERROR;
966         }
967         break;
968 
969     case TLS_ST_SW_CERT_REQ:
970         if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
971             if (statem_flush(s) != 1)
972                 return WORK_MORE_A;
973         }
974         break;
975 
976     case TLS_ST_SW_KEY_UPDATE:
977         if (statem_flush(s) != 1)
978             return WORK_MORE_A;
979         if (!tls13_update_key(s, 1)) {
980             /* SSLfatal() already called */
981             return WORK_ERROR;
982         }
983         break;
984 
985     case TLS_ST_SW_SESSION_TICKET:
986         clear_sys_error();
987         if (SSL_IS_TLS13(s) && statem_flush(s) != 1) {
988             if (SSL_get_error(s, 0) == SSL_ERROR_SYSCALL
989                     && conn_is_closed()) {
990                 /*
991                  * We ignore connection closed errors in TLSv1.3 when sending a
992                  * NewSessionTicket and behave as if we were successful. This is
993                  * so that we are still able to read data sent to us by a client
994                  * that closes soon after the end of the handshake without
995                  * waiting to read our post-handshake NewSessionTickets.
996                  */
997                 s->rwstate = SSL_NOTHING;
998                 break;
999             }
1000 
1001             return WORK_MORE_A;
1002         }
1003         break;
1004     }
1005 
1006     return WORK_FINISHED_CONTINUE;
1007 }
1008 
1009 /*
1010  * Get the message construction function and message type for sending from the
1011  * server
1012  *
1013  * Valid return values are:
1014  *   1: Success
1015  *   0: Error
1016  */
1017 int ossl_statem_server_construct_message(SSL *s, WPACKET *pkt,
1018                                          confunc_f *confunc, int *mt)
1019 {
1020     OSSL_STATEM *st = &s->statem;
1021 
1022     switch (st->hand_state) {
1023     default:
1024         /* Shouldn't happen */
1025         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_STATE);
1026         return 0;
1027 
1028     case TLS_ST_SW_CHANGE:
1029         if (SSL_IS_DTLS(s))
1030             *confunc = dtls_construct_change_cipher_spec;
1031         else
1032             *confunc = tls_construct_change_cipher_spec;
1033         *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
1034         break;
1035 
1036     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
1037         *confunc = dtls_construct_hello_verify_request;
1038         *mt = DTLS1_MT_HELLO_VERIFY_REQUEST;
1039         break;
1040 
1041     case TLS_ST_SW_HELLO_REQ:
1042         /* No construction function needed */
1043         *confunc = NULL;
1044         *mt = SSL3_MT_HELLO_REQUEST;
1045         break;
1046 
1047     case TLS_ST_SW_SRVR_HELLO:
1048         *confunc = tls_construct_server_hello;
1049         *mt = SSL3_MT_SERVER_HELLO;
1050         break;
1051 
1052     case TLS_ST_SW_CERT:
1053         *confunc = tls_construct_server_certificate;
1054         *mt = SSL3_MT_CERTIFICATE;
1055         break;
1056 
1057     case TLS_ST_SW_CERT_VRFY:
1058         *confunc = tls_construct_cert_verify;
1059         *mt = SSL3_MT_CERTIFICATE_VERIFY;
1060         break;
1061 
1062 
1063     case TLS_ST_SW_KEY_EXCH:
1064         *confunc = tls_construct_server_key_exchange;
1065         *mt = SSL3_MT_SERVER_KEY_EXCHANGE;
1066         break;
1067 
1068     case TLS_ST_SW_CERT_REQ:
1069         *confunc = tls_construct_certificate_request;
1070         *mt = SSL3_MT_CERTIFICATE_REQUEST;
1071         break;
1072 
1073     case TLS_ST_SW_SRVR_DONE:
1074         *confunc = tls_construct_server_done;
1075         *mt = SSL3_MT_SERVER_DONE;
1076         break;
1077 
1078     case TLS_ST_SW_SESSION_TICKET:
1079         *confunc = tls_construct_new_session_ticket;
1080         *mt = SSL3_MT_NEWSESSION_TICKET;
1081         break;
1082 
1083     case TLS_ST_SW_CERT_STATUS:
1084         *confunc = tls_construct_cert_status;
1085         *mt = SSL3_MT_CERTIFICATE_STATUS;
1086         break;
1087 
1088     case TLS_ST_SW_FINISHED:
1089         *confunc = tls_construct_finished;
1090         *mt = SSL3_MT_FINISHED;
1091         break;
1092 
1093     case TLS_ST_EARLY_DATA:
1094         *confunc = NULL;
1095         *mt = SSL3_MT_DUMMY;
1096         break;
1097 
1098     case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
1099         *confunc = tls_construct_encrypted_extensions;
1100         *mt = SSL3_MT_ENCRYPTED_EXTENSIONS;
1101         break;
1102 
1103     case TLS_ST_SW_KEY_UPDATE:
1104         *confunc = tls_construct_key_update;
1105         *mt = SSL3_MT_KEY_UPDATE;
1106         break;
1107     }
1108 
1109     return 1;
1110 }
1111 
1112 /*
1113  * Maximum size (excluding the Handshake header) of a ClientHello message,
1114  * calculated as follows:
1115  *
1116  *  2 + # client_version
1117  *  32 + # only valid length for random
1118  *  1 + # length of session_id
1119  *  32 + # maximum size for session_id
1120  *  2 + # length of cipher suites
1121  *  2^16-2 + # maximum length of cipher suites array
1122  *  1 + # length of compression_methods
1123  *  2^8-1 + # maximum length of compression methods
1124  *  2 + # length of extensions
1125  *  2^16-1 # maximum length of extensions
1126  */
1127 #define CLIENT_HELLO_MAX_LENGTH         131396
1128 
1129 #define CLIENT_KEY_EXCH_MAX_LENGTH      2048
1130 #define NEXT_PROTO_MAX_LENGTH           514
1131 
1132 /*
1133  * Returns the maximum allowed length for the current message that we are
1134  * reading. Excludes the message header.
1135  */
1136 size_t ossl_statem_server_max_message_size(SSL *s)
1137 {
1138     OSSL_STATEM *st = &s->statem;
1139 
1140     switch (st->hand_state) {
1141     default:
1142         /* Shouldn't happen */
1143         return 0;
1144 
1145     case TLS_ST_SR_CLNT_HELLO:
1146         return CLIENT_HELLO_MAX_LENGTH;
1147 
1148     case TLS_ST_SR_END_OF_EARLY_DATA:
1149         return END_OF_EARLY_DATA_MAX_LENGTH;
1150 
1151     case TLS_ST_SR_CERT:
1152         return s->max_cert_list;
1153 
1154     case TLS_ST_SR_KEY_EXCH:
1155         return CLIENT_KEY_EXCH_MAX_LENGTH;
1156 
1157     case TLS_ST_SR_CERT_VRFY:
1158         return SSL3_RT_MAX_PLAIN_LENGTH;
1159 
1160 #ifndef OPENSSL_NO_NEXTPROTONEG
1161     case TLS_ST_SR_NEXT_PROTO:
1162         return NEXT_PROTO_MAX_LENGTH;
1163 #endif
1164 
1165     case TLS_ST_SR_CHANGE:
1166         return CCS_MAX_LENGTH;
1167 
1168     case TLS_ST_SR_FINISHED:
1169         return FINISHED_MAX_LENGTH;
1170 
1171     case TLS_ST_SR_KEY_UPDATE:
1172         return KEY_UPDATE_MAX_LENGTH;
1173     }
1174 }
1175 
1176 /*
1177  * Process a message that the server has received from the client.
1178  */
1179 MSG_PROCESS_RETURN ossl_statem_server_process_message(SSL *s, PACKET *pkt)
1180 {
1181     OSSL_STATEM *st = &s->statem;
1182 
1183     switch (st->hand_state) {
1184     default:
1185         /* Shouldn't happen */
1186         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1187         return MSG_PROCESS_ERROR;
1188 
1189     case TLS_ST_SR_CLNT_HELLO:
1190         return tls_process_client_hello(s, pkt);
1191 
1192     case TLS_ST_SR_END_OF_EARLY_DATA:
1193         return tls_process_end_of_early_data(s, pkt);
1194 
1195     case TLS_ST_SR_CERT:
1196         return tls_process_client_certificate(s, pkt);
1197 
1198     case TLS_ST_SR_KEY_EXCH:
1199         return tls_process_client_key_exchange(s, pkt);
1200 
1201     case TLS_ST_SR_CERT_VRFY:
1202         return tls_process_cert_verify(s, pkt);
1203 
1204 #ifndef OPENSSL_NO_NEXTPROTONEG
1205     case TLS_ST_SR_NEXT_PROTO:
1206         return tls_process_next_proto(s, pkt);
1207 #endif
1208 
1209     case TLS_ST_SR_CHANGE:
1210         return tls_process_change_cipher_spec(s, pkt);
1211 
1212     case TLS_ST_SR_FINISHED:
1213         return tls_process_finished(s, pkt);
1214 
1215     case TLS_ST_SR_KEY_UPDATE:
1216         return tls_process_key_update(s, pkt);
1217 
1218     }
1219 }
1220 
1221 /*
1222  * Perform any further processing required following the receipt of a message
1223  * from the client
1224  */
1225 WORK_STATE ossl_statem_server_post_process_message(SSL *s, WORK_STATE wst)
1226 {
1227     OSSL_STATEM *st = &s->statem;
1228 
1229     switch (st->hand_state) {
1230     default:
1231         /* Shouldn't happen */
1232         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1233         return WORK_ERROR;
1234 
1235     case TLS_ST_SR_CLNT_HELLO:
1236         return tls_post_process_client_hello(s, wst);
1237 
1238     case TLS_ST_SR_KEY_EXCH:
1239         return tls_post_process_client_key_exchange(s, wst);
1240     }
1241 }
1242 
1243 #ifndef OPENSSL_NO_SRP
1244 /* Returns 1 on success, 0 for retryable error, -1 for fatal error */
1245 static int ssl_check_srp_ext_ClientHello(SSL *s)
1246 {
1247     int ret;
1248     int al = SSL_AD_UNRECOGNIZED_NAME;
1249 
1250     if ((s->s3.tmp.new_cipher->algorithm_mkey & SSL_kSRP) &&
1251         (s->srp_ctx.TLS_ext_srp_username_callback != NULL)) {
1252         if (s->srp_ctx.login == NULL) {
1253             /*
1254              * RFC 5054 says SHOULD reject, we do so if There is no srp
1255              * login name
1256              */
1257             SSLfatal(s, SSL_AD_UNKNOWN_PSK_IDENTITY,
1258                      SSL_R_PSK_IDENTITY_NOT_FOUND);
1259             return -1;
1260         } else {
1261             ret = ssl_srp_server_param_with_username_intern(s, &al);
1262             if (ret < 0)
1263                 return 0;
1264             if (ret == SSL3_AL_FATAL) {
1265                 SSLfatal(s, al,
1266                          al == SSL_AD_UNKNOWN_PSK_IDENTITY
1267                          ? SSL_R_PSK_IDENTITY_NOT_FOUND
1268                          : SSL_R_CLIENTHELLO_TLSEXT);
1269                 return -1;
1270             }
1271         }
1272     }
1273     return 1;
1274 }
1275 #endif
1276 
1277 int dtls_raw_hello_verify_request(WPACKET *pkt, unsigned char *cookie,
1278                                   size_t cookie_len)
1279 {
1280     /* Always use DTLS 1.0 version: see RFC 6347 */
1281     if (!WPACKET_put_bytes_u16(pkt, DTLS1_VERSION)
1282             || !WPACKET_sub_memcpy_u8(pkt, cookie, cookie_len))
1283         return 0;
1284 
1285     return 1;
1286 }
1287 
1288 int dtls_construct_hello_verify_request(SSL *s, WPACKET *pkt)
1289 {
1290     unsigned int cookie_leni;
1291     if (s->ctx->app_gen_cookie_cb == NULL ||
1292         s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
1293                                   &cookie_leni) == 0 ||
1294         cookie_leni > DTLS1_COOKIE_LENGTH) {
1295         SSLfatal(s, SSL_AD_NO_ALERT, SSL_R_COOKIE_GEN_CALLBACK_FAILURE);
1296         return 0;
1297     }
1298     s->d1->cookie_len = cookie_leni;
1299 
1300     if (!dtls_raw_hello_verify_request(pkt, s->d1->cookie,
1301                                               s->d1->cookie_len)) {
1302         SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
1303         return 0;
1304     }
1305 
1306     return 1;
1307 }
1308 
1309 /*-
1310  * ssl_check_for_safari attempts to fingerprint Safari using OS X
1311  * SecureTransport using the TLS extension block in |hello|.
1312  * Safari, since 10.6, sends exactly these extensions, in this order:
1313  *   SNI,
1314  *   elliptic_curves
1315  *   ec_point_formats
1316  *   signature_algorithms (for TLSv1.2 only)
1317  *
1318  * We wish to fingerprint Safari because they broke ECDHE-ECDSA support in 10.8,
1319  * but they advertise support. So enabling ECDHE-ECDSA ciphers breaks them.
1320  * Sadly we cannot differentiate 10.6, 10.7 and 10.8.4 (which work), from
1321  * 10.8..10.8.3 (which don't work).
1322  */
1323 static void ssl_check_for_safari(SSL *s, const CLIENTHELLO_MSG *hello)
1324 {
1325     static const unsigned char kSafariExtensionsBlock[] = {
1326         0x00, 0x0a,             /* elliptic_curves extension */
1327         0x00, 0x08,             /* 8 bytes */
1328         0x00, 0x06,             /* 6 bytes of curve ids */
1329         0x00, 0x17,             /* P-256 */
1330         0x00, 0x18,             /* P-384 */
1331         0x00, 0x19,             /* P-521 */
1332 
1333         0x00, 0x0b,             /* ec_point_formats */
1334         0x00, 0x02,             /* 2 bytes */
1335         0x01,                   /* 1 point format */
1336         0x00,                   /* uncompressed */
1337         /* The following is only present in TLS 1.2 */
1338         0x00, 0x0d,             /* signature_algorithms */
1339         0x00, 0x0c,             /* 12 bytes */
1340         0x00, 0x0a,             /* 10 bytes */
1341         0x05, 0x01,             /* SHA-384/RSA */
1342         0x04, 0x01,             /* SHA-256/RSA */
1343         0x02, 0x01,             /* SHA-1/RSA */
1344         0x04, 0x03,             /* SHA-256/ECDSA */
1345         0x02, 0x03,             /* SHA-1/ECDSA */
1346     };
1347     /* Length of the common prefix (first two extensions). */
1348     static const size_t kSafariCommonExtensionsLength = 18;
1349     unsigned int type;
1350     PACKET sni, tmppkt;
1351     size_t ext_len;
1352 
1353     tmppkt = hello->extensions;
1354 
1355     if (!PACKET_forward(&tmppkt, 2)
1356         || !PACKET_get_net_2(&tmppkt, &type)
1357         || !PACKET_get_length_prefixed_2(&tmppkt, &sni)) {
1358         return;
1359     }
1360 
1361     if (type != TLSEXT_TYPE_server_name)
1362         return;
1363 
1364     ext_len = TLS1_get_client_version(s) >= TLS1_2_VERSION ?
1365         sizeof(kSafariExtensionsBlock) : kSafariCommonExtensionsLength;
1366 
1367     s->s3.is_probably_safari = PACKET_equal(&tmppkt, kSafariExtensionsBlock,
1368                                              ext_len);
1369 }
1370 
1371 #define RENEG_OPTIONS_OK(options) \
1372     ((options & SSL_OP_NO_RENEGOTIATION) == 0 \
1373      && (options & SSL_OP_ALLOW_CLIENT_RENEGOTIATION) != 0)
1374 
1375 MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
1376 {
1377     /* |cookie| will only be initialized for DTLS. */
1378     PACKET session_id, compression, extensions, cookie;
1379     static const unsigned char null_compression = 0;
1380     CLIENTHELLO_MSG *clienthello = NULL;
1381 
1382     /* Check if this is actually an unexpected renegotiation ClientHello */
1383     if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) {
1384         if (!ossl_assert(!SSL_IS_TLS13(s))) {
1385             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1386             goto err;
1387         }
1388         if (!RENEG_OPTIONS_OK(s->options)
1389                 || (!s->s3.send_connection_binding
1390                     && (s->options
1391                         & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) == 0)) {
1392             ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1393             return MSG_PROCESS_FINISHED_READING;
1394         }
1395         s->renegotiate = 1;
1396         s->new_session = 1;
1397     }
1398 
1399     clienthello = OPENSSL_zalloc(sizeof(*clienthello));
1400     if (clienthello == NULL) {
1401         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1402         goto err;
1403     }
1404 
1405     /*
1406      * First, parse the raw ClientHello data into the CLIENTHELLO_MSG structure.
1407      */
1408     clienthello->isv2 = RECORD_LAYER_is_sslv2_record(&s->rlayer);
1409     PACKET_null_init(&cookie);
1410 
1411     if (clienthello->isv2) {
1412         unsigned int mt;
1413 
1414         if (!SSL_IS_FIRST_HANDSHAKE(s)
1415                 || s->hello_retry_request != SSL_HRR_NONE) {
1416             SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
1417             goto err;
1418         }
1419 
1420         /*-
1421          * An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
1422          * header is sent directly on the wire, not wrapped as a TLS
1423          * record. Our record layer just processes the message length and passes
1424          * the rest right through. Its format is:
1425          * Byte  Content
1426          * 0-1   msg_length - decoded by the record layer
1427          * 2     msg_type - s->init_msg points here
1428          * 3-4   version
1429          * 5-6   cipher_spec_length
1430          * 7-8   session_id_length
1431          * 9-10  challenge_length
1432          * ...   ...
1433          */
1434 
1435         if (!PACKET_get_1(pkt, &mt)
1436             || mt != SSL2_MT_CLIENT_HELLO) {
1437             /*
1438              * Should never happen. We should have tested this in the record
1439              * layer in order to have determined that this is a SSLv2 record
1440              * in the first place
1441              */
1442             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1443             goto err;
1444         }
1445     }
1446 
1447     if (!PACKET_get_net_2(pkt, &clienthello->legacy_version)) {
1448         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
1449         goto err;
1450     }
1451 
1452     /* Parse the message and load client random. */
1453     if (clienthello->isv2) {
1454         /*
1455          * Handle an SSLv2 backwards compatible ClientHello
1456          * Note, this is only for SSLv3+ using the backward compatible format.
1457          * Real SSLv2 is not supported, and is rejected below.
1458          */
1459         unsigned int ciphersuite_len, session_id_len, challenge_len;
1460         PACKET challenge;
1461 
1462         if (!PACKET_get_net_2(pkt, &ciphersuite_len)
1463             || !PACKET_get_net_2(pkt, &session_id_len)
1464             || !PACKET_get_net_2(pkt, &challenge_len)) {
1465             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RECORD_LENGTH_MISMATCH);
1466             goto err;
1467         }
1468 
1469         if (session_id_len > SSL_MAX_SSL_SESSION_ID_LENGTH) {
1470             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_LENGTH_MISMATCH);
1471             goto err;
1472         }
1473 
1474         if (!PACKET_get_sub_packet(pkt, &clienthello->ciphersuites,
1475                                    ciphersuite_len)
1476             || !PACKET_copy_bytes(pkt, clienthello->session_id, session_id_len)
1477             || !PACKET_get_sub_packet(pkt, &challenge, challenge_len)
1478             /* No extensions. */
1479             || PACKET_remaining(pkt) != 0) {
1480             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RECORD_LENGTH_MISMATCH);
1481             goto err;
1482         }
1483         clienthello->session_id_len = session_id_len;
1484 
1485         /* Load the client random and compression list. We use SSL3_RANDOM_SIZE
1486          * here rather than sizeof(clienthello->random) because that is the limit
1487          * for SSLv3 and it is fixed. It won't change even if
1488          * sizeof(clienthello->random) does.
1489          */
1490         challenge_len = challenge_len > SSL3_RANDOM_SIZE
1491                         ? SSL3_RANDOM_SIZE : challenge_len;
1492         memset(clienthello->random, 0, SSL3_RANDOM_SIZE);
1493         if (!PACKET_copy_bytes(&challenge,
1494                                clienthello->random + SSL3_RANDOM_SIZE -
1495                                challenge_len, challenge_len)
1496             /* Advertise only null compression. */
1497             || !PACKET_buf_init(&compression, &null_compression, 1)) {
1498             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1499             goto err;
1500         }
1501 
1502         PACKET_null_init(&clienthello->extensions);
1503     } else {
1504         /* Regular ClientHello. */
1505         if (!PACKET_copy_bytes(pkt, clienthello->random, SSL3_RANDOM_SIZE)
1506             || !PACKET_get_length_prefixed_1(pkt, &session_id)
1507             || !PACKET_copy_all(&session_id, clienthello->session_id,
1508                     SSL_MAX_SSL_SESSION_ID_LENGTH,
1509                     &clienthello->session_id_len)) {
1510             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1511             goto err;
1512         }
1513 
1514         if (SSL_IS_DTLS(s)) {
1515             if (!PACKET_get_length_prefixed_1(pkt, &cookie)) {
1516                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1517                 goto err;
1518             }
1519             if (!PACKET_copy_all(&cookie, clienthello->dtls_cookie,
1520                                  DTLS1_COOKIE_LENGTH,
1521                                  &clienthello->dtls_cookie_len)) {
1522                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1523                 goto err;
1524             }
1525             /*
1526              * If we require cookies and this ClientHello doesn't contain one,
1527              * just return since we do not want to allocate any memory yet.
1528              * So check cookie length...
1529              */
1530             if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
1531                 if (clienthello->dtls_cookie_len == 0) {
1532                     OPENSSL_free(clienthello);
1533                     return MSG_PROCESS_FINISHED_READING;
1534                 }
1535             }
1536         }
1537 
1538         if (!PACKET_get_length_prefixed_2(pkt, &clienthello->ciphersuites)) {
1539             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1540             goto err;
1541         }
1542 
1543         if (!PACKET_get_length_prefixed_1(pkt, &compression)) {
1544             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1545             goto err;
1546         }
1547 
1548         /* Could be empty. */
1549         if (PACKET_remaining(pkt) == 0) {
1550             PACKET_null_init(&clienthello->extensions);
1551         } else {
1552             if (!PACKET_get_length_prefixed_2(pkt, &clienthello->extensions)
1553                     || PACKET_remaining(pkt) != 0) {
1554                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1555                 goto err;
1556             }
1557         }
1558     }
1559 
1560     if (!PACKET_copy_all(&compression, clienthello->compressions,
1561                          MAX_COMPRESSIONS_SIZE,
1562                          &clienthello->compressions_len)) {
1563         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1564         goto err;
1565     }
1566 
1567     /* Preserve the raw extensions PACKET for later use */
1568     extensions = clienthello->extensions;
1569     if (!tls_collect_extensions(s, &extensions, SSL_EXT_CLIENT_HELLO,
1570                                 &clienthello->pre_proc_exts,
1571                                 &clienthello->pre_proc_exts_len, 1)) {
1572         /* SSLfatal already been called */
1573         goto err;
1574     }
1575     s->clienthello = clienthello;
1576 
1577     return MSG_PROCESS_CONTINUE_PROCESSING;
1578 
1579  err:
1580     if (clienthello != NULL)
1581         OPENSSL_free(clienthello->pre_proc_exts);
1582     OPENSSL_free(clienthello);
1583 
1584     return MSG_PROCESS_ERROR;
1585 }
1586 
1587 static int tls_early_post_process_client_hello(SSL *s)
1588 {
1589     unsigned int j;
1590     int i, al = SSL_AD_INTERNAL_ERROR;
1591     int protverr;
1592     size_t loop;
1593     unsigned long id;
1594 #ifndef OPENSSL_NO_COMP
1595     SSL_COMP *comp = NULL;
1596 #endif
1597     const SSL_CIPHER *c;
1598     STACK_OF(SSL_CIPHER) *ciphers = NULL;
1599     STACK_OF(SSL_CIPHER) *scsvs = NULL;
1600     CLIENTHELLO_MSG *clienthello = s->clienthello;
1601     DOWNGRADE dgrd = DOWNGRADE_NONE;
1602 
1603     /* Finished parsing the ClientHello, now we can start processing it */
1604     /* Give the ClientHello callback a crack at things */
1605     if (s->ctx->client_hello_cb != NULL) {
1606         /* A failure in the ClientHello callback terminates the connection. */
1607         switch (s->ctx->client_hello_cb(s, &al, s->ctx->client_hello_cb_arg)) {
1608         case SSL_CLIENT_HELLO_SUCCESS:
1609             break;
1610         case SSL_CLIENT_HELLO_RETRY:
1611             s->rwstate = SSL_CLIENT_HELLO_CB;
1612             return -1;
1613         case SSL_CLIENT_HELLO_ERROR:
1614         default:
1615             SSLfatal(s, al, SSL_R_CALLBACK_FAILED);
1616             goto err;
1617         }
1618     }
1619 
1620     /* Set up the client_random */
1621     memcpy(s->s3.client_random, clienthello->random, SSL3_RANDOM_SIZE);
1622 
1623     /* Choose the version */
1624 
1625     if (clienthello->isv2) {
1626         if (clienthello->legacy_version == SSL2_VERSION
1627                 || (clienthello->legacy_version & 0xff00)
1628                    != (SSL3_VERSION_MAJOR << 8)) {
1629             /*
1630              * This is real SSLv2 or something completely unknown. We don't
1631              * support it.
1632              */
1633             SSLfatal(s, SSL_AD_PROTOCOL_VERSION, SSL_R_UNKNOWN_PROTOCOL);
1634             goto err;
1635         }
1636         /* SSLv3/TLS */
1637         s->client_version = clienthello->legacy_version;
1638     }
1639     /*
1640      * Do SSL/TLS version negotiation if applicable. For DTLS we just check
1641      * versions are potentially compatible. Version negotiation comes later.
1642      */
1643     if (!SSL_IS_DTLS(s)) {
1644         protverr = ssl_choose_server_version(s, clienthello, &dgrd);
1645     } else if (s->method->version != DTLS_ANY_VERSION &&
1646                DTLS_VERSION_LT((int)clienthello->legacy_version, s->version)) {
1647         protverr = SSL_R_VERSION_TOO_LOW;
1648     } else {
1649         protverr = 0;
1650     }
1651 
1652     if (protverr) {
1653         if (SSL_IS_FIRST_HANDSHAKE(s)) {
1654             /* like ssl3_get_record, send alert using remote version number */
1655             s->version = s->client_version = clienthello->legacy_version;
1656         }
1657         SSLfatal(s, SSL_AD_PROTOCOL_VERSION, protverr);
1658         goto err;
1659     }
1660 
1661     /* TLSv1.3 specifies that a ClientHello must end on a record boundary */
1662     if (SSL_IS_TLS13(s) && RECORD_LAYER_processed_read_pending(&s->rlayer)) {
1663         SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_NOT_ON_RECORD_BOUNDARY);
1664         goto err;
1665     }
1666 
1667     if (SSL_IS_DTLS(s)) {
1668         /* Empty cookie was already handled above by returning early. */
1669         if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
1670             if (s->ctx->app_verify_cookie_cb != NULL) {
1671                 if (s->ctx->app_verify_cookie_cb(s, clienthello->dtls_cookie,
1672                         clienthello->dtls_cookie_len) == 0) {
1673                     SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1674                              SSL_R_COOKIE_MISMATCH);
1675                     goto err;
1676                     /* else cookie verification succeeded */
1677                 }
1678                 /* default verification */
1679             } else if (s->d1->cookie_len != clienthello->dtls_cookie_len
1680                     || memcmp(clienthello->dtls_cookie, s->d1->cookie,
1681                               s->d1->cookie_len) != 0) {
1682                 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_COOKIE_MISMATCH);
1683                 goto err;
1684             }
1685             s->d1->cookie_verified = 1;
1686         }
1687         if (s->method->version == DTLS_ANY_VERSION) {
1688             protverr = ssl_choose_server_version(s, clienthello, &dgrd);
1689             if (protverr != 0) {
1690                 s->version = s->client_version;
1691                 SSLfatal(s, SSL_AD_PROTOCOL_VERSION, protverr);
1692                 goto err;
1693             }
1694         }
1695     }
1696 
1697     s->hit = 0;
1698 
1699     if (!ssl_cache_cipherlist(s, &clienthello->ciphersuites,
1700                               clienthello->isv2) ||
1701         !bytes_to_cipher_list(s, &clienthello->ciphersuites, &ciphers, &scsvs,
1702                               clienthello->isv2, 1)) {
1703         /* SSLfatal() already called */
1704         goto err;
1705     }
1706 
1707     s->s3.send_connection_binding = 0;
1708     /* Check what signalling cipher-suite values were received. */
1709     if (scsvs != NULL) {
1710         for(i = 0; i < sk_SSL_CIPHER_num(scsvs); i++) {
1711             c = sk_SSL_CIPHER_value(scsvs, i);
1712             if (SSL_CIPHER_get_id(c) == SSL3_CK_SCSV) {
1713                 if (s->renegotiate) {
1714                     /* SCSV is fatal if renegotiating */
1715                     SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1716                              SSL_R_SCSV_RECEIVED_WHEN_RENEGOTIATING);
1717                     goto err;
1718                 }
1719                 s->s3.send_connection_binding = 1;
1720             } else if (SSL_CIPHER_get_id(c) == SSL3_CK_FALLBACK_SCSV &&
1721                        !ssl_check_version_downgrade(s)) {
1722                 /*
1723                  * This SCSV indicates that the client previously tried
1724                  * a higher version.  We should fail if the current version
1725                  * is an unexpected downgrade, as that indicates that the first
1726                  * connection may have been tampered with in order to trigger
1727                  * an insecure downgrade.
1728                  */
1729                 SSLfatal(s, SSL_AD_INAPPROPRIATE_FALLBACK,
1730                          SSL_R_INAPPROPRIATE_FALLBACK);
1731                 goto err;
1732             }
1733         }
1734     }
1735 
1736     /* For TLSv1.3 we must select the ciphersuite *before* session resumption */
1737     if (SSL_IS_TLS13(s)) {
1738         const SSL_CIPHER *cipher =
1739             ssl3_choose_cipher(s, ciphers, SSL_get_ciphers(s));
1740 
1741         if (cipher == NULL) {
1742             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_NO_SHARED_CIPHER);
1743             goto err;
1744         }
1745         if (s->hello_retry_request == SSL_HRR_PENDING
1746                 && (s->s3.tmp.new_cipher == NULL
1747                     || s->s3.tmp.new_cipher->id != cipher->id)) {
1748             /*
1749              * A previous HRR picked a different ciphersuite to the one we
1750              * just selected. Something must have changed.
1751              */
1752             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_CIPHER);
1753             goto err;
1754         }
1755         s->s3.tmp.new_cipher = cipher;
1756     }
1757 
1758     /* We need to do this before getting the session */
1759     if (!tls_parse_extension(s, TLSEXT_IDX_extended_master_secret,
1760                              SSL_EXT_CLIENT_HELLO,
1761                              clienthello->pre_proc_exts, NULL, 0)) {
1762         /* SSLfatal() already called */
1763         goto err;
1764     }
1765 
1766     /*
1767      * We don't allow resumption in a backwards compatible ClientHello.
1768      * In TLS1.1+, session_id MUST be empty.
1769      *
1770      * Versions before 0.9.7 always allow clients to resume sessions in
1771      * renegotiation. 0.9.7 and later allow this by default, but optionally
1772      * ignore resumption requests with flag
1773      * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather
1774      * than a change to default behavior so that applications relying on
1775      * this for security won't even compile against older library versions).
1776      * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to
1777      * request renegotiation but not a new session (s->new_session remains
1778      * unset): for servers, this essentially just means that the
1779      * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be
1780      * ignored.
1781      */
1782     if (clienthello->isv2 ||
1783         (s->new_session &&
1784          (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) {
1785         if (!ssl_get_new_session(s, 1)) {
1786             /* SSLfatal() already called */
1787             goto err;
1788         }
1789     } else {
1790         i = ssl_get_prev_session(s, clienthello);
1791         if (i == 1) {
1792             /* previous session */
1793             s->hit = 1;
1794         } else if (i == -1) {
1795             /* SSLfatal() already called */
1796             goto err;
1797         } else {
1798             /* i == 0 */
1799             if (!ssl_get_new_session(s, 1)) {
1800                 /* SSLfatal() already called */
1801                 goto err;
1802             }
1803         }
1804     }
1805 
1806     if (SSL_IS_TLS13(s)) {
1807         memcpy(s->tmp_session_id, s->clienthello->session_id,
1808                s->clienthello->session_id_len);
1809         s->tmp_session_id_len = s->clienthello->session_id_len;
1810     }
1811 
1812     /*
1813      * If it is a hit, check that the cipher is in the list. In TLSv1.3 we check
1814      * ciphersuite compatibility with the session as part of resumption.
1815      */
1816     if (!SSL_IS_TLS13(s) && s->hit) {
1817         j = 0;
1818         id = s->session->cipher->id;
1819 
1820         OSSL_TRACE_BEGIN(TLS_CIPHER) {
1821             BIO_printf(trc_out, "client sent %d ciphers\n",
1822                        sk_SSL_CIPHER_num(ciphers));
1823         }
1824         for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) {
1825             c = sk_SSL_CIPHER_value(ciphers, i);
1826             if (trc_out != NULL)
1827                 BIO_printf(trc_out, "client [%2d of %2d]:%s\n", i,
1828                            sk_SSL_CIPHER_num(ciphers), SSL_CIPHER_get_name(c));
1829             if (c->id == id) {
1830                 j = 1;
1831                 break;
1832             }
1833         }
1834         if (j == 0) {
1835             /*
1836              * we need to have the cipher in the cipher list if we are asked
1837              * to reuse it
1838              */
1839             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1840                      SSL_R_REQUIRED_CIPHER_MISSING);
1841             OSSL_TRACE_CANCEL(TLS_CIPHER);
1842             goto err;
1843         }
1844         OSSL_TRACE_END(TLS_CIPHER);
1845     }
1846 
1847     for (loop = 0; loop < clienthello->compressions_len; loop++) {
1848         if (clienthello->compressions[loop] == 0)
1849             break;
1850     }
1851 
1852     if (loop >= clienthello->compressions_len) {
1853         /* no compress */
1854         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_NO_COMPRESSION_SPECIFIED);
1855         goto err;
1856     }
1857 
1858     if (s->options & SSL_OP_SAFARI_ECDHE_ECDSA_BUG)
1859         ssl_check_for_safari(s, clienthello);
1860 
1861     /* TLS extensions */
1862     if (!tls_parse_all_extensions(s, SSL_EXT_CLIENT_HELLO,
1863                                   clienthello->pre_proc_exts, NULL, 0, 1)) {
1864         /* SSLfatal() already called */
1865         goto err;
1866     }
1867 
1868     /*
1869      * Check if we want to use external pre-shared secret for this handshake
1870      * for not reused session only. We need to generate server_random before
1871      * calling tls_session_secret_cb in order to allow SessionTicket
1872      * processing to use it in key derivation.
1873      */
1874     {
1875         unsigned char *pos;
1876         pos = s->s3.server_random;
1877         if (ssl_fill_hello_random(s, 1, pos, SSL3_RANDOM_SIZE, dgrd) <= 0) {
1878             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1879             goto err;
1880         }
1881     }
1882 
1883     if (!s->hit
1884             && s->version >= TLS1_VERSION
1885             && !SSL_IS_TLS13(s)
1886             && !SSL_IS_DTLS(s)
1887             && s->ext.session_secret_cb) {
1888         const SSL_CIPHER *pref_cipher = NULL;
1889         /*
1890          * s->session->master_key_length is a size_t, but this is an int for
1891          * backwards compat reasons
1892          */
1893         int master_key_length;
1894 
1895         master_key_length = sizeof(s->session->master_key);
1896         if (s->ext.session_secret_cb(s, s->session->master_key,
1897                                      &master_key_length, ciphers,
1898                                      &pref_cipher,
1899                                      s->ext.session_secret_cb_arg)
1900                 && master_key_length > 0) {
1901             s->session->master_key_length = master_key_length;
1902             s->hit = 1;
1903             s->peer_ciphers = ciphers;
1904             s->session->verify_result = X509_V_OK;
1905 
1906             ciphers = NULL;
1907 
1908             /* check if some cipher was preferred by call back */
1909             if (pref_cipher == NULL)
1910                 pref_cipher = ssl3_choose_cipher(s, s->peer_ciphers,
1911                                                  SSL_get_ciphers(s));
1912             if (pref_cipher == NULL) {
1913                 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_NO_SHARED_CIPHER);
1914                 goto err;
1915             }
1916 
1917             s->session->cipher = pref_cipher;
1918             sk_SSL_CIPHER_free(s->cipher_list);
1919             s->cipher_list = sk_SSL_CIPHER_dup(s->peer_ciphers);
1920             sk_SSL_CIPHER_free(s->cipher_list_by_id);
1921             s->cipher_list_by_id = sk_SSL_CIPHER_dup(s->peer_ciphers);
1922         }
1923     }
1924 
1925     /*
1926      * Worst case, we will use the NULL compression, but if we have other
1927      * options, we will now look for them.  We have complen-1 compression
1928      * algorithms from the client, starting at q.
1929      */
1930     s->s3.tmp.new_compression = NULL;
1931     if (SSL_IS_TLS13(s)) {
1932         /*
1933          * We already checked above that the NULL compression method appears in
1934          * the list. Now we check there aren't any others (which is illegal in
1935          * a TLSv1.3 ClientHello.
1936          */
1937         if (clienthello->compressions_len != 1) {
1938             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1939                      SSL_R_INVALID_COMPRESSION_ALGORITHM);
1940             goto err;
1941         }
1942     }
1943 #ifndef OPENSSL_NO_COMP
1944     /* This only happens if we have a cache hit */
1945     else if (s->session->compress_meth != 0) {
1946         int m, comp_id = s->session->compress_meth;
1947         unsigned int k;
1948         /* Perform sanity checks on resumed compression algorithm */
1949         /* Can't disable compression */
1950         if (!ssl_allow_compression(s)) {
1951             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1952                      SSL_R_INCONSISTENT_COMPRESSION);
1953             goto err;
1954         }
1955         /* Look for resumed compression method */
1956         for (m = 0; m < sk_SSL_COMP_num(s->ctx->comp_methods); m++) {
1957             comp = sk_SSL_COMP_value(s->ctx->comp_methods, m);
1958             if (comp_id == comp->id) {
1959                 s->s3.tmp.new_compression = comp;
1960                 break;
1961             }
1962         }
1963         if (s->s3.tmp.new_compression == NULL) {
1964             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1965                      SSL_R_INVALID_COMPRESSION_ALGORITHM);
1966             goto err;
1967         }
1968         /* Look for resumed method in compression list */
1969         for (k = 0; k < clienthello->compressions_len; k++) {
1970             if (clienthello->compressions[k] == comp_id)
1971                 break;
1972         }
1973         if (k >= clienthello->compressions_len) {
1974             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1975                      SSL_R_REQUIRED_COMPRESSION_ALGORITHM_MISSING);
1976             goto err;
1977         }
1978     } else if (s->hit) {
1979         comp = NULL;
1980     } else if (ssl_allow_compression(s) && s->ctx->comp_methods) {
1981         /* See if we have a match */
1982         int m, nn, v, done = 0;
1983         unsigned int o;
1984 
1985         nn = sk_SSL_COMP_num(s->ctx->comp_methods);
1986         for (m = 0; m < nn; m++) {
1987             comp = sk_SSL_COMP_value(s->ctx->comp_methods, m);
1988             v = comp->id;
1989             for (o = 0; o < clienthello->compressions_len; o++) {
1990                 if (v == clienthello->compressions[o]) {
1991                     done = 1;
1992                     break;
1993                 }
1994             }
1995             if (done)
1996                 break;
1997         }
1998         if (done)
1999             s->s3.tmp.new_compression = comp;
2000         else
2001             comp = NULL;
2002     }
2003 #else
2004     /*
2005      * If compression is disabled we'd better not try to resume a session
2006      * using compression.
2007      */
2008     if (s->session->compress_meth != 0) {
2009         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_INCONSISTENT_COMPRESSION);
2010         goto err;
2011     }
2012 #endif
2013 
2014     /*
2015      * Given s->peer_ciphers and SSL_get_ciphers, we must pick a cipher
2016      */
2017 
2018     if (!s->hit || SSL_IS_TLS13(s)) {
2019         sk_SSL_CIPHER_free(s->peer_ciphers);
2020         s->peer_ciphers = ciphers;
2021         if (ciphers == NULL) {
2022             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2023             goto err;
2024         }
2025         ciphers = NULL;
2026     }
2027 
2028     if (!s->hit) {
2029 #ifdef OPENSSL_NO_COMP
2030         s->session->compress_meth = 0;
2031 #else
2032         s->session->compress_meth = (comp == NULL) ? 0 : comp->id;
2033 #endif
2034         if (!tls1_set_server_sigalgs(s)) {
2035             /* SSLfatal() already called */
2036             goto err;
2037         }
2038     }
2039 
2040     sk_SSL_CIPHER_free(ciphers);
2041     sk_SSL_CIPHER_free(scsvs);
2042     OPENSSL_free(clienthello->pre_proc_exts);
2043     OPENSSL_free(s->clienthello);
2044     s->clienthello = NULL;
2045     return 1;
2046  err:
2047     sk_SSL_CIPHER_free(ciphers);
2048     sk_SSL_CIPHER_free(scsvs);
2049     OPENSSL_free(clienthello->pre_proc_exts);
2050     OPENSSL_free(s->clienthello);
2051     s->clienthello = NULL;
2052 
2053     return 0;
2054 }
2055 
2056 /*
2057  * Call the status request callback if needed. Upon success, returns 1.
2058  * Upon failure, returns 0.
2059  */
2060 static int tls_handle_status_request(SSL *s)
2061 {
2062     s->ext.status_expected = 0;
2063 
2064     /*
2065      * If status request then ask callback what to do. Note: this must be
2066      * called after servername callbacks in case the certificate has changed,
2067      * and must be called after the cipher has been chosen because this may
2068      * influence which certificate is sent
2069      */
2070     if (s->ext.status_type != TLSEXT_STATUSTYPE_nothing && s->ctx != NULL
2071             && s->ctx->ext.status_cb != NULL) {
2072         int ret;
2073 
2074         /* If no certificate can't return certificate status */
2075         if (s->s3.tmp.cert != NULL) {
2076             /*
2077              * Set current certificate to one we will use so SSL_get_certificate
2078              * et al can pick it up.
2079              */
2080             s->cert->key = s->s3.tmp.cert;
2081             ret = s->ctx->ext.status_cb(s, s->ctx->ext.status_arg);
2082             switch (ret) {
2083                 /* We don't want to send a status request response */
2084             case SSL_TLSEXT_ERR_NOACK:
2085                 s->ext.status_expected = 0;
2086                 break;
2087                 /* status request response should be sent */
2088             case SSL_TLSEXT_ERR_OK:
2089                 if (s->ext.ocsp.resp)
2090                     s->ext.status_expected = 1;
2091                 break;
2092                 /* something bad happened */
2093             case SSL_TLSEXT_ERR_ALERT_FATAL:
2094             default:
2095                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_CLIENTHELLO_TLSEXT);
2096                 return 0;
2097             }
2098         }
2099     }
2100 
2101     return 1;
2102 }
2103 
2104 /*
2105  * Call the alpn_select callback if needed. Upon success, returns 1.
2106  * Upon failure, returns 0.
2107  */
2108 int tls_handle_alpn(SSL *s)
2109 {
2110     const unsigned char *selected = NULL;
2111     unsigned char selected_len = 0;
2112 
2113     if (s->ctx->ext.alpn_select_cb != NULL && s->s3.alpn_proposed != NULL) {
2114         int r = s->ctx->ext.alpn_select_cb(s, &selected, &selected_len,
2115                                            s->s3.alpn_proposed,
2116                                            (unsigned int)s->s3.alpn_proposed_len,
2117                                            s->ctx->ext.alpn_select_cb_arg);
2118 
2119         if (r == SSL_TLSEXT_ERR_OK) {
2120             OPENSSL_free(s->s3.alpn_selected);
2121             s->s3.alpn_selected = OPENSSL_memdup(selected, selected_len);
2122             if (s->s3.alpn_selected == NULL) {
2123                 s->s3.alpn_selected_len = 0;
2124                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2125                 return 0;
2126             }
2127             s->s3.alpn_selected_len = selected_len;
2128 #ifndef OPENSSL_NO_NEXTPROTONEG
2129             /* ALPN takes precedence over NPN. */
2130             s->s3.npn_seen = 0;
2131 #endif
2132 
2133             /* Check ALPN is consistent with session */
2134             if (s->session->ext.alpn_selected == NULL
2135                         || selected_len != s->session->ext.alpn_selected_len
2136                         || memcmp(selected, s->session->ext.alpn_selected,
2137                                   selected_len) != 0) {
2138                 /* Not consistent so can't be used for early_data */
2139                 s->ext.early_data_ok = 0;
2140 
2141                 if (!s->hit) {
2142                     /*
2143                      * This is a new session and so alpn_selected should have
2144                      * been initialised to NULL. We should update it with the
2145                      * selected ALPN.
2146                      */
2147                     if (!ossl_assert(s->session->ext.alpn_selected == NULL)) {
2148                         SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2149                                  ERR_R_INTERNAL_ERROR);
2150                         return 0;
2151                     }
2152                     s->session->ext.alpn_selected = OPENSSL_memdup(selected,
2153                                                                    selected_len);
2154                     if (s->session->ext.alpn_selected == NULL) {
2155                         SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2156                                  ERR_R_INTERNAL_ERROR);
2157                         return 0;
2158                     }
2159                     s->session->ext.alpn_selected_len = selected_len;
2160                 }
2161             }
2162 
2163             return 1;
2164         } else if (r != SSL_TLSEXT_ERR_NOACK) {
2165             SSLfatal(s, SSL_AD_NO_APPLICATION_PROTOCOL,
2166                      SSL_R_NO_APPLICATION_PROTOCOL);
2167             return 0;
2168         }
2169         /*
2170          * If r == SSL_TLSEXT_ERR_NOACK then behave as if no callback was
2171          * present.
2172          */
2173     }
2174 
2175     /* Check ALPN is consistent with session */
2176     if (s->session->ext.alpn_selected != NULL) {
2177         /* Not consistent so can't be used for early_data */
2178         s->ext.early_data_ok = 0;
2179     }
2180 
2181     return 1;
2182 }
2183 
2184 WORK_STATE tls_post_process_client_hello(SSL *s, WORK_STATE wst)
2185 {
2186     const SSL_CIPHER *cipher;
2187 
2188     if (wst == WORK_MORE_A) {
2189         int rv = tls_early_post_process_client_hello(s);
2190         if (rv == 0) {
2191             /* SSLfatal() was already called */
2192             goto err;
2193         }
2194         if (rv < 0)
2195             return WORK_MORE_A;
2196         wst = WORK_MORE_B;
2197     }
2198     if (wst == WORK_MORE_B) {
2199         if (!s->hit || SSL_IS_TLS13(s)) {
2200             /* Let cert callback update server certificates if required */
2201             if (!s->hit && s->cert->cert_cb != NULL) {
2202                 int rv = s->cert->cert_cb(s, s->cert->cert_cb_arg);
2203                 if (rv == 0) {
2204                     SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_CERT_CB_ERROR);
2205                     goto err;
2206                 }
2207                 if (rv < 0) {
2208                     s->rwstate = SSL_X509_LOOKUP;
2209                     return WORK_MORE_B;
2210                 }
2211                 s->rwstate = SSL_NOTHING;
2212             }
2213 
2214             /* In TLSv1.3 we selected the ciphersuite before resumption */
2215             if (!SSL_IS_TLS13(s)) {
2216                 cipher =
2217                     ssl3_choose_cipher(s, s->peer_ciphers, SSL_get_ciphers(s));
2218 
2219                 if (cipher == NULL) {
2220                     SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2221                              SSL_R_NO_SHARED_CIPHER);
2222                     goto err;
2223                 }
2224                 s->s3.tmp.new_cipher = cipher;
2225             }
2226             if (!s->hit) {
2227                 if (!tls_choose_sigalg(s, 1)) {
2228                     /* SSLfatal already called */
2229                     goto err;
2230                 }
2231                 /* check whether we should disable session resumption */
2232                 if (s->not_resumable_session_cb != NULL)
2233                     s->session->not_resumable =
2234                         s->not_resumable_session_cb(s,
2235                             ((s->s3.tmp.new_cipher->algorithm_mkey
2236                               & (SSL_kDHE | SSL_kECDHE)) != 0));
2237                 if (s->session->not_resumable)
2238                     /* do not send a session ticket */
2239                     s->ext.ticket_expected = 0;
2240             }
2241         } else {
2242             /* Session-id reuse */
2243             s->s3.tmp.new_cipher = s->session->cipher;
2244         }
2245 
2246         /*-
2247          * we now have the following setup.
2248          * client_random
2249          * cipher_list          - our preferred list of ciphers
2250          * ciphers              - the clients preferred list of ciphers
2251          * compression          - basically ignored right now
2252          * ssl version is set   - sslv3
2253          * s->session           - The ssl session has been setup.
2254          * s->hit               - session reuse flag
2255          * s->s3.tmp.new_cipher - the new cipher to use.
2256          */
2257 
2258         /*
2259          * Call status_request callback if needed. Has to be done after the
2260          * certificate callbacks etc above.
2261          */
2262         if (!tls_handle_status_request(s)) {
2263             /* SSLfatal() already called */
2264             goto err;
2265         }
2266         /*
2267          * Call alpn_select callback if needed.  Has to be done after SNI and
2268          * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3
2269          * we already did this because cipher negotiation happens earlier, and
2270          * we must handle ALPN before we decide whether to accept early_data.
2271          */
2272         if (!SSL_IS_TLS13(s) && !tls_handle_alpn(s)) {
2273             /* SSLfatal() already called */
2274             goto err;
2275         }
2276 
2277         wst = WORK_MORE_C;
2278     }
2279 #ifndef OPENSSL_NO_SRP
2280     if (wst == WORK_MORE_C) {
2281         int ret;
2282         if ((ret = ssl_check_srp_ext_ClientHello(s)) == 0) {
2283             /*
2284              * callback indicates further work to be done
2285              */
2286             s->rwstate = SSL_X509_LOOKUP;
2287             return WORK_MORE_C;
2288         }
2289         if (ret < 0) {
2290             /* SSLfatal() already called */
2291             goto err;
2292         }
2293     }
2294 #endif
2295 
2296     return WORK_FINISHED_STOP;
2297  err:
2298     return WORK_ERROR;
2299 }
2300 
2301 int tls_construct_server_hello(SSL *s, WPACKET *pkt)
2302 {
2303     int compm;
2304     size_t sl, len;
2305     int version;
2306     unsigned char *session_id;
2307     int usetls13 = SSL_IS_TLS13(s) || s->hello_retry_request == SSL_HRR_PENDING;
2308 
2309     version = usetls13 ? TLS1_2_VERSION : s->version;
2310     if (!WPACKET_put_bytes_u16(pkt, version)
2311                /*
2312                 * Random stuff. Filling of the server_random takes place in
2313                 * tls_process_client_hello()
2314                 */
2315             || !WPACKET_memcpy(pkt,
2316                                s->hello_retry_request == SSL_HRR_PENDING
2317                                    ? hrrrandom : s->s3.server_random,
2318                                SSL3_RANDOM_SIZE)) {
2319         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2320         return 0;
2321     }
2322 
2323     /*-
2324      * There are several cases for the session ID to send
2325      * back in the server hello:
2326      * - For session reuse from the session cache,
2327      *   we send back the old session ID.
2328      * - If stateless session reuse (using a session ticket)
2329      *   is successful, we send back the client's "session ID"
2330      *   (which doesn't actually identify the session).
2331      * - If it is a new session, we send back the new
2332      *   session ID.
2333      * - However, if we want the new session to be single-use,
2334      *   we send back a 0-length session ID.
2335      * - In TLSv1.3 we echo back the session id sent to us by the client
2336      *   regardless
2337      * s->hit is non-zero in either case of session reuse,
2338      * so the following won't overwrite an ID that we're supposed
2339      * to send back.
2340      */
2341     if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
2342             && !s->hit)
2343         s->session->session_id_length = 0;
2344 
2345     if (usetls13) {
2346         sl = s->tmp_session_id_len;
2347         session_id = s->tmp_session_id;
2348     } else {
2349         sl = s->session->session_id_length;
2350         session_id = s->session->session_id;
2351     }
2352 
2353     if (sl > sizeof(s->session->session_id)) {
2354         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2355         return 0;
2356     }
2357 
2358     /* set up the compression method */
2359 #ifdef OPENSSL_NO_COMP
2360     compm = 0;
2361 #else
2362     if (usetls13 || s->s3.tmp.new_compression == NULL)
2363         compm = 0;
2364     else
2365         compm = s->s3.tmp.new_compression->id;
2366 #endif
2367 
2368     if (!WPACKET_sub_memcpy_u8(pkt, session_id, sl)
2369             || !s->method->put_cipher_by_char(s->s3.tmp.new_cipher, pkt, &len)
2370             || !WPACKET_put_bytes_u8(pkt, compm)) {
2371         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2372         return 0;
2373     }
2374 
2375     if (!tls_construct_extensions(s, pkt,
2376                                   s->hello_retry_request == SSL_HRR_PENDING
2377                                       ? SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
2378                                       : (SSL_IS_TLS13(s)
2379                                           ? SSL_EXT_TLS1_3_SERVER_HELLO
2380                                           : SSL_EXT_TLS1_2_SERVER_HELLO),
2381                                   NULL, 0)) {
2382         /* SSLfatal() already called */
2383         return 0;
2384     }
2385 
2386     if (s->hello_retry_request == SSL_HRR_PENDING) {
2387         /* Ditch the session. We'll create a new one next time around */
2388         SSL_SESSION_free(s->session);
2389         s->session = NULL;
2390         s->hit = 0;
2391 
2392         /*
2393          * Re-initialise the Transcript Hash. We're going to prepopulate it with
2394          * a synthetic message_hash in place of ClientHello1.
2395          */
2396         if (!create_synthetic_message_hash(s, NULL, 0, NULL, 0)) {
2397             /* SSLfatal() already called */
2398             return 0;
2399         }
2400     } else if (!(s->verify_mode & SSL_VERIFY_PEER)
2401                 && !ssl3_digest_cached_records(s, 0)) {
2402         /* SSLfatal() already called */;
2403         return 0;
2404     }
2405 
2406     return 1;
2407 }
2408 
2409 int tls_construct_server_done(SSL *s, WPACKET *pkt)
2410 {
2411     if (!s->s3.tmp.cert_request) {
2412         if (!ssl3_digest_cached_records(s, 0)) {
2413             /* SSLfatal() already called */
2414             return 0;
2415         }
2416     }
2417     return 1;
2418 }
2419 
2420 int tls_construct_server_key_exchange(SSL *s, WPACKET *pkt)
2421 {
2422     EVP_PKEY *pkdh = NULL;
2423     unsigned char *encodedPoint = NULL;
2424     size_t encodedlen = 0;
2425     int curve_id = 0;
2426     const SIGALG_LOOKUP *lu = s->s3.tmp.sigalg;
2427     int i;
2428     unsigned long type;
2429     BIGNUM *r[4];
2430     EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
2431     EVP_PKEY_CTX *pctx = NULL;
2432     size_t paramlen, paramoffset;
2433     int freer = 0, ret = 0;
2434 
2435     if (!WPACKET_get_total_written(pkt, &paramoffset)) {
2436         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2437         goto err;
2438     }
2439 
2440     if (md_ctx == NULL) {
2441         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2442         goto err;
2443     }
2444 
2445     type = s->s3.tmp.new_cipher->algorithm_mkey;
2446 
2447     r[0] = r[1] = r[2] = r[3] = NULL;
2448 #ifndef OPENSSL_NO_PSK
2449     /* Plain PSK or RSAPSK nothing to do */
2450     if (type & (SSL_kPSK | SSL_kRSAPSK)) {
2451     } else
2452 #endif                          /* !OPENSSL_NO_PSK */
2453     if (type & (SSL_kDHE | SSL_kDHEPSK)) {
2454         CERT *cert = s->cert;
2455         EVP_PKEY *pkdhp = NULL;
2456 
2457         if (s->cert->dh_tmp_auto) {
2458             pkdh = ssl_get_auto_dh(s);
2459             if (pkdh == NULL) {
2460                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2461                 goto err;
2462             }
2463             pkdhp = pkdh;
2464         } else {
2465             pkdhp = cert->dh_tmp;
2466         }
2467 #if !defined(OPENSSL_NO_DEPRECATED_3_0)
2468         if ((pkdhp == NULL) && (s->cert->dh_tmp_cb != NULL)) {
2469             pkdh = ssl_dh_to_pkey(s->cert->dh_tmp_cb(s, 0, 1024));
2470             if (pkdh == NULL) {
2471                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2472                 goto err;
2473             }
2474             pkdhp = pkdh;
2475         }
2476 #endif
2477         if (pkdhp == NULL) {
2478             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_TMP_DH_KEY);
2479             goto err;
2480         }
2481         if (!ssl_security(s, SSL_SECOP_TMP_DH,
2482                           EVP_PKEY_get_security_bits(pkdhp), 0, pkdhp)) {
2483             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_DH_KEY_TOO_SMALL);
2484             goto err;
2485         }
2486         if (s->s3.tmp.pkey != NULL) {
2487             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2488             goto err;
2489         }
2490 
2491         s->s3.tmp.pkey = ssl_generate_pkey(s, pkdhp);
2492         if (s->s3.tmp.pkey == NULL) {
2493             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2494             goto err;
2495         }
2496 
2497         EVP_PKEY_free(pkdh);
2498         pkdh = NULL;
2499 
2500         /* These BIGNUMs need to be freed when we're finished */
2501         freer = 1;
2502         if (!EVP_PKEY_get_bn_param(s->s3.tmp.pkey, OSSL_PKEY_PARAM_FFC_P,
2503                                    &r[0])
2504                 || !EVP_PKEY_get_bn_param(s->s3.tmp.pkey, OSSL_PKEY_PARAM_FFC_G,
2505                                           &r[1])
2506                 || !EVP_PKEY_get_bn_param(s->s3.tmp.pkey,
2507                                           OSSL_PKEY_PARAM_PUB_KEY, &r[2])) {
2508             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2509             goto err;
2510         }
2511     } else if (type & (SSL_kECDHE | SSL_kECDHEPSK)) {
2512 
2513         if (s->s3.tmp.pkey != NULL) {
2514             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2515             goto err;
2516         }
2517 
2518         /* Get NID of appropriate shared curve */
2519         curve_id = tls1_shared_group(s, -2);
2520         if (curve_id == 0) {
2521             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2522                      SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
2523             goto err;
2524         }
2525         /* Cache the group used in the SSL_SESSION */
2526         s->session->kex_group = curve_id;
2527         /* Generate a new key for this curve */
2528         s->s3.tmp.pkey = ssl_generate_pkey_group(s, curve_id);
2529         if (s->s3.tmp.pkey == NULL) {
2530             /* SSLfatal() already called */
2531             goto err;
2532         }
2533 
2534         /* Encode the public key. */
2535         encodedlen = EVP_PKEY_get1_encoded_public_key(s->s3.tmp.pkey,
2536                                                       &encodedPoint);
2537         if (encodedlen == 0) {
2538             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EC_LIB);
2539             goto err;
2540         }
2541 
2542         /*
2543          * We'll generate the serverKeyExchange message explicitly so we
2544          * can set these to NULLs
2545          */
2546         r[0] = NULL;
2547         r[1] = NULL;
2548         r[2] = NULL;
2549         r[3] = NULL;
2550     } else
2551 #ifndef OPENSSL_NO_SRP
2552     if (type & SSL_kSRP) {
2553         if ((s->srp_ctx.N == NULL) ||
2554             (s->srp_ctx.g == NULL) ||
2555             (s->srp_ctx.s == NULL) || (s->srp_ctx.B == NULL)) {
2556             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_SRP_PARAM);
2557             goto err;
2558         }
2559         r[0] = s->srp_ctx.N;
2560         r[1] = s->srp_ctx.g;
2561         r[2] = s->srp_ctx.s;
2562         r[3] = s->srp_ctx.B;
2563     } else
2564 #endif
2565     {
2566         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
2567         goto err;
2568     }
2569 
2570     if (((s->s3.tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP)) != 0)
2571         || ((s->s3.tmp.new_cipher->algorithm_mkey & SSL_PSK)) != 0) {
2572         lu = NULL;
2573     } else if (lu == NULL) {
2574         SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_INTERNAL_ERROR);
2575         goto err;
2576     }
2577 
2578 #ifndef OPENSSL_NO_PSK
2579     if (type & SSL_PSK) {
2580         size_t len = (s->cert->psk_identity_hint == NULL)
2581                         ? 0 : strlen(s->cert->psk_identity_hint);
2582 
2583         /*
2584          * It should not happen that len > PSK_MAX_IDENTITY_LEN - we already
2585          * checked this when we set the identity hint - but just in case
2586          */
2587         if (len > PSK_MAX_IDENTITY_LEN
2588                 || !WPACKET_sub_memcpy_u16(pkt, s->cert->psk_identity_hint,
2589                                            len)) {
2590             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2591             goto err;
2592         }
2593     }
2594 #endif
2595 
2596     for (i = 0; i < 4 && r[i] != NULL; i++) {
2597         unsigned char *binval;
2598         int res;
2599 
2600 #ifndef OPENSSL_NO_SRP
2601         if ((i == 2) && (type & SSL_kSRP)) {
2602             res = WPACKET_start_sub_packet_u8(pkt);
2603         } else
2604 #endif
2605             res = WPACKET_start_sub_packet_u16(pkt);
2606 
2607         if (!res) {
2608             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2609             goto err;
2610         }
2611 
2612         /*-
2613          * for interoperability with some versions of the Microsoft TLS
2614          * stack, we need to zero pad the DHE pub key to the same length
2615          * as the prime
2616          */
2617         if ((i == 2) && (type & (SSL_kDHE | SSL_kDHEPSK))) {
2618             size_t len = BN_num_bytes(r[0]) - BN_num_bytes(r[2]);
2619 
2620             if (len > 0) {
2621                 if (!WPACKET_allocate_bytes(pkt, len, &binval)) {
2622                     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2623                     goto err;
2624                 }
2625                 memset(binval, 0, len);
2626             }
2627         }
2628 
2629         if (!WPACKET_allocate_bytes(pkt, BN_num_bytes(r[i]), &binval)
2630                 || !WPACKET_close(pkt)) {
2631             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2632             goto err;
2633         }
2634 
2635         BN_bn2bin(r[i], binval);
2636     }
2637 
2638     if (type & (SSL_kECDHE | SSL_kECDHEPSK)) {
2639         /*
2640          * We only support named (not generic) curves. In this situation, the
2641          * ServerKeyExchange message has: [1 byte CurveType], [2 byte CurveName]
2642          * [1 byte length of encoded point], followed by the actual encoded
2643          * point itself
2644          */
2645         if (!WPACKET_put_bytes_u8(pkt, NAMED_CURVE_TYPE)
2646                 || !WPACKET_put_bytes_u8(pkt, 0)
2647                 || !WPACKET_put_bytes_u8(pkt, curve_id)
2648                 || !WPACKET_sub_memcpy_u8(pkt, encodedPoint, encodedlen)) {
2649             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2650             goto err;
2651         }
2652         OPENSSL_free(encodedPoint);
2653         encodedPoint = NULL;
2654     }
2655 
2656     /* not anonymous */
2657     if (lu != NULL) {
2658         EVP_PKEY *pkey = s->s3.tmp.cert->privatekey;
2659         const EVP_MD *md;
2660         unsigned char *sigbytes1, *sigbytes2, *tbs;
2661         size_t siglen = 0, tbslen;
2662 
2663         if (pkey == NULL || !tls1_lookup_md(s->ctx, lu, &md)) {
2664             /* Should never happen */
2665             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2666             goto err;
2667         }
2668         /* Get length of the parameters we have written above */
2669         if (!WPACKET_get_length(pkt, &paramlen)) {
2670             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2671             goto err;
2672         }
2673         /* send signature algorithm */
2674         if (SSL_USE_SIGALGS(s) && !WPACKET_put_bytes_u16(pkt, lu->sigalg)) {
2675             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2676             goto err;
2677         }
2678 
2679         if (EVP_DigestSignInit_ex(md_ctx, &pctx,
2680                                   md == NULL ? NULL : EVP_MD_get0_name(md),
2681                                   s->ctx->libctx, s->ctx->propq, pkey,
2682                                   NULL) <= 0) {
2683             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2684             goto err;
2685         }
2686         if (lu->sig == EVP_PKEY_RSA_PSS) {
2687             if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
2688                 || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, RSA_PSS_SALTLEN_DIGEST) <= 0) {
2689                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
2690                 goto err;
2691             }
2692         }
2693         tbslen = construct_key_exchange_tbs(s, &tbs,
2694                                             s->init_buf->data + paramoffset,
2695                                             paramlen);
2696         if (tbslen == 0) {
2697             /* SSLfatal() already called */
2698             goto err;
2699         }
2700 
2701         if (EVP_DigestSign(md_ctx, NULL, &siglen, tbs, tbslen) <=0
2702                 || !WPACKET_sub_reserve_bytes_u16(pkt, siglen, &sigbytes1)
2703                 || EVP_DigestSign(md_ctx, sigbytes1, &siglen, tbs, tbslen) <= 0
2704                 || !WPACKET_sub_allocate_bytes_u16(pkt, siglen, &sigbytes2)
2705                 || sigbytes1 != sigbytes2) {
2706             OPENSSL_free(tbs);
2707             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2708             goto err;
2709         }
2710         OPENSSL_free(tbs);
2711     }
2712 
2713     ret = 1;
2714  err:
2715     EVP_PKEY_free(pkdh);
2716     OPENSSL_free(encodedPoint);
2717     EVP_MD_CTX_free(md_ctx);
2718     if (freer) {
2719         BN_free(r[0]);
2720         BN_free(r[1]);
2721         BN_free(r[2]);
2722         BN_free(r[3]);
2723     }
2724     return ret;
2725 }
2726 
2727 int tls_construct_certificate_request(SSL *s, WPACKET *pkt)
2728 {
2729     if (SSL_IS_TLS13(s)) {
2730         /* Send random context when doing post-handshake auth */
2731         if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
2732             OPENSSL_free(s->pha_context);
2733             s->pha_context_len = 32;
2734             if ((s->pha_context = OPENSSL_malloc(s->pha_context_len)) == NULL) {
2735                 s->pha_context_len = 0;
2736                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2737                 return 0;
2738             }
2739             if (RAND_bytes_ex(s->ctx->libctx, s->pha_context,
2740                                      s->pha_context_len, 0) <= 0
2741                     || !WPACKET_sub_memcpy_u8(pkt, s->pha_context,
2742                                               s->pha_context_len)) {
2743                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2744                 return 0;
2745             }
2746             /* reset the handshake hash back to just after the ClientFinished */
2747             if (!tls13_restore_handshake_digest_for_pha(s)) {
2748                 /* SSLfatal() already called */
2749                 return 0;
2750             }
2751         } else {
2752             if (!WPACKET_put_bytes_u8(pkt, 0)) {
2753                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2754                 return 0;
2755             }
2756         }
2757 
2758         if (!tls_construct_extensions(s, pkt,
2759                                       SSL_EXT_TLS1_3_CERTIFICATE_REQUEST, NULL,
2760                                       0)) {
2761             /* SSLfatal() already called */
2762             return 0;
2763         }
2764         goto done;
2765     }
2766 
2767     /* get the list of acceptable cert types */
2768     if (!WPACKET_start_sub_packet_u8(pkt)
2769         || !ssl3_get_req_cert_type(s, pkt) || !WPACKET_close(pkt)) {
2770         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2771         return 0;
2772     }
2773 
2774     if (SSL_USE_SIGALGS(s)) {
2775         const uint16_t *psigs;
2776         size_t nl = tls12_get_psigalgs(s, 1, &psigs);
2777 
2778         if (!WPACKET_start_sub_packet_u16(pkt)
2779                 || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH)
2780                 || !tls12_copy_sigalgs(s, pkt, psigs, nl)
2781                 || !WPACKET_close(pkt)) {
2782             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2783             return 0;
2784         }
2785     }
2786 
2787     if (!construct_ca_names(s, get_ca_names(s), pkt)) {
2788         /* SSLfatal() already called */
2789         return 0;
2790     }
2791 
2792  done:
2793     s->certreqs_sent++;
2794     s->s3.tmp.cert_request = 1;
2795     return 1;
2796 }
2797 
2798 static int tls_process_cke_psk_preamble(SSL *s, PACKET *pkt)
2799 {
2800 #ifndef OPENSSL_NO_PSK
2801     unsigned char psk[PSK_MAX_PSK_LEN];
2802     size_t psklen;
2803     PACKET psk_identity;
2804 
2805     if (!PACKET_get_length_prefixed_2(pkt, &psk_identity)) {
2806         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2807         return 0;
2808     }
2809     if (PACKET_remaining(&psk_identity) > PSK_MAX_IDENTITY_LEN) {
2810         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DATA_LENGTH_TOO_LONG);
2811         return 0;
2812     }
2813     if (s->psk_server_callback == NULL) {
2814         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PSK_NO_SERVER_CB);
2815         return 0;
2816     }
2817 
2818     if (!PACKET_strndup(&psk_identity, &s->session->psk_identity)) {
2819         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2820         return 0;
2821     }
2822 
2823     psklen = s->psk_server_callback(s, s->session->psk_identity,
2824                                     psk, sizeof(psk));
2825 
2826     if (psklen > PSK_MAX_PSK_LEN) {
2827         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2828         return 0;
2829     } else if (psklen == 0) {
2830         /*
2831          * PSK related to the given identity not found
2832          */
2833         SSLfatal(s, SSL_AD_UNKNOWN_PSK_IDENTITY, SSL_R_PSK_IDENTITY_NOT_FOUND);
2834         return 0;
2835     }
2836 
2837     OPENSSL_free(s->s3.tmp.psk);
2838     s->s3.tmp.psk = OPENSSL_memdup(psk, psklen);
2839     OPENSSL_cleanse(psk, psklen);
2840 
2841     if (s->s3.tmp.psk == NULL) {
2842         s->s3.tmp.psklen = 0;
2843         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2844         return 0;
2845     }
2846 
2847     s->s3.tmp.psklen = psklen;
2848 
2849     return 1;
2850 #else
2851     /* Should never happen */
2852     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2853     return 0;
2854 #endif
2855 }
2856 
2857 static int tls_process_cke_rsa(SSL *s, PACKET *pkt)
2858 {
2859     size_t outlen;
2860     PACKET enc_premaster;
2861     EVP_PKEY *rsa = NULL;
2862     unsigned char *rsa_decrypt = NULL;
2863     int ret = 0;
2864     EVP_PKEY_CTX *ctx = NULL;
2865     OSSL_PARAM params[3], *p = params;
2866 
2867     rsa = s->cert->pkeys[SSL_PKEY_RSA].privatekey;
2868     if (rsa == NULL) {
2869         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_RSA_CERTIFICATE);
2870         return 0;
2871     }
2872 
2873     /* SSLv3 and pre-standard DTLS omit the length bytes. */
2874     if (s->version == SSL3_VERSION || s->version == DTLS1_BAD_VER) {
2875         enc_premaster = *pkt;
2876     } else {
2877         if (!PACKET_get_length_prefixed_2(pkt, &enc_premaster)
2878             || PACKET_remaining(pkt) != 0) {
2879             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2880             return 0;
2881         }
2882     }
2883 
2884     outlen = SSL_MAX_MASTER_KEY_LENGTH;
2885     rsa_decrypt = OPENSSL_malloc(outlen);
2886     if (rsa_decrypt == NULL) {
2887         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2888         return 0;
2889     }
2890 
2891     ctx = EVP_PKEY_CTX_new_from_pkey(s->ctx->libctx, rsa, s->ctx->propq);
2892     if (ctx == NULL) {
2893         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
2894         goto err;
2895     }
2896 
2897     /*
2898      * We must not leak whether a decryption failure occurs because of
2899      * Bleichenbacher's attack on PKCS #1 v1.5 RSA padding (see RFC 2246,
2900      * section 7.4.7.1). We use the special padding type
2901      * RSA_PKCS1_WITH_TLS_PADDING to do that. It will automaticaly decrypt the
2902      * RSA, check the padding and check that the client version is as expected
2903      * in the premaster secret. If any of that fails then the function appears
2904      * to return successfully but with a random result. The call below could
2905      * still fail if the input is publicly invalid.
2906      * See https://tools.ietf.org/html/rfc5246#section-7.4.7.1
2907      */
2908     if (EVP_PKEY_decrypt_init(ctx) <= 0
2909             || EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_WITH_TLS_PADDING) <= 0) {
2910         SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_R_DECRYPTION_FAILED);
2911         goto err;
2912     }
2913 
2914     *p++ = OSSL_PARAM_construct_uint(OSSL_ASYM_CIPHER_PARAM_TLS_CLIENT_VERSION,
2915                                      (unsigned int *)&s->client_version);
2916    if ((s->options & SSL_OP_TLS_ROLLBACK_BUG) != 0)
2917         *p++ = OSSL_PARAM_construct_uint(
2918             OSSL_ASYM_CIPHER_PARAM_TLS_NEGOTIATED_VERSION,
2919             (unsigned int *)&s->version);
2920     *p++ = OSSL_PARAM_construct_end();
2921 
2922     if (!EVP_PKEY_CTX_set_params(ctx, params)
2923             || EVP_PKEY_decrypt(ctx, rsa_decrypt, &outlen,
2924                                 PACKET_data(&enc_premaster),
2925                                 PACKET_remaining(&enc_premaster)) <= 0) {
2926         SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_R_DECRYPTION_FAILED);
2927         goto err;
2928     }
2929 
2930     /*
2931      * This test should never fail (otherwise we should have failed above) but
2932      * we double check anyway.
2933      */
2934     if (outlen != SSL_MAX_MASTER_KEY_LENGTH) {
2935         OPENSSL_cleanse(rsa_decrypt, SSL_MAX_MASTER_KEY_LENGTH);
2936         SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_R_DECRYPTION_FAILED);
2937         goto err;
2938     }
2939 
2940     /* Also cleanses rsa_decrypt (on success or failure) */
2941     if (!ssl_generate_master_secret(s, rsa_decrypt,
2942                                     SSL_MAX_MASTER_KEY_LENGTH, 0)) {
2943         /* SSLfatal() already called */
2944         goto err;
2945     }
2946 
2947     ret = 1;
2948  err:
2949     OPENSSL_free(rsa_decrypt);
2950     EVP_PKEY_CTX_free(ctx);
2951     return ret;
2952 }
2953 
2954 static int tls_process_cke_dhe(SSL *s, PACKET *pkt)
2955 {
2956     EVP_PKEY *skey = NULL;
2957     unsigned int i;
2958     const unsigned char *data;
2959     EVP_PKEY *ckey = NULL;
2960     int ret = 0;
2961 
2962     if (!PACKET_get_net_2(pkt, &i) || PACKET_remaining(pkt) != i) {
2963         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG);
2964         goto err;
2965     }
2966     skey = s->s3.tmp.pkey;
2967     if (skey == NULL) {
2968         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_TMP_DH_KEY);
2969         goto err;
2970     }
2971 
2972     if (PACKET_remaining(pkt) == 0L) {
2973         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_MISSING_TMP_DH_KEY);
2974         goto err;
2975     }
2976     if (!PACKET_get_bytes(pkt, &data, i)) {
2977         /* We already checked we have enough data */
2978         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2979         goto err;
2980     }
2981     ckey = EVP_PKEY_new();
2982     if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) == 0) {
2983         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COPY_PARAMETERS_FAILED);
2984         goto err;
2985     }
2986 
2987     if (!EVP_PKEY_set1_encoded_public_key(ckey, data, i)) {
2988         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2989         goto err;
2990     }
2991 
2992     if (ssl_derive(s, skey, ckey, 1) == 0) {
2993         /* SSLfatal() already called */
2994         goto err;
2995     }
2996 
2997     ret = 1;
2998     EVP_PKEY_free(s->s3.tmp.pkey);
2999     s->s3.tmp.pkey = NULL;
3000  err:
3001     EVP_PKEY_free(ckey);
3002     return ret;
3003 }
3004 
3005 static int tls_process_cke_ecdhe(SSL *s, PACKET *pkt)
3006 {
3007     EVP_PKEY *skey = s->s3.tmp.pkey;
3008     EVP_PKEY *ckey = NULL;
3009     int ret = 0;
3010 
3011     if (PACKET_remaining(pkt) == 0L) {
3012         /* We don't support ECDH client auth */
3013         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_MISSING_TMP_ECDH_KEY);
3014         goto err;
3015     } else {
3016         unsigned int i;
3017         const unsigned char *data;
3018 
3019         /*
3020          * Get client's public key from encoded point in the
3021          * ClientKeyExchange message.
3022          */
3023 
3024         /* Get encoded point length */
3025         if (!PACKET_get_1(pkt, &i) || !PACKET_get_bytes(pkt, &data, i)
3026             || PACKET_remaining(pkt) != 0) {
3027             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3028             goto err;
3029         }
3030         if (skey == NULL) {
3031             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_TMP_ECDH_KEY);
3032             goto err;
3033         }
3034 
3035         ckey = EVP_PKEY_new();
3036         if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) <= 0) {
3037             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COPY_PARAMETERS_FAILED);
3038             goto err;
3039         }
3040 
3041         if (EVP_PKEY_set1_encoded_public_key(ckey, data, i) <= 0) {
3042             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EC_LIB);
3043             goto err;
3044         }
3045     }
3046 
3047     if (ssl_derive(s, skey, ckey, 1) == 0) {
3048         /* SSLfatal() already called */
3049         goto err;
3050     }
3051 
3052     ret = 1;
3053     EVP_PKEY_free(s->s3.tmp.pkey);
3054     s->s3.tmp.pkey = NULL;
3055  err:
3056     EVP_PKEY_free(ckey);
3057 
3058     return ret;
3059 }
3060 
3061 static int tls_process_cke_srp(SSL *s, PACKET *pkt)
3062 {
3063 #ifndef OPENSSL_NO_SRP
3064     unsigned int i;
3065     const unsigned char *data;
3066 
3067     if (!PACKET_get_net_2(pkt, &i)
3068         || !PACKET_get_bytes(pkt, &data, i)) {
3069         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_SRP_A_LENGTH);
3070         return 0;
3071     }
3072     if ((s->srp_ctx.A = BN_bin2bn(data, i, NULL)) == NULL) {
3073         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BN_LIB);
3074         return 0;
3075     }
3076     if (BN_ucmp(s->srp_ctx.A, s->srp_ctx.N) >= 0 || BN_is_zero(s->srp_ctx.A)) {
3077         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_SRP_PARAMETERS);
3078         return 0;
3079     }
3080     OPENSSL_free(s->session->srp_username);
3081     s->session->srp_username = OPENSSL_strdup(s->srp_ctx.login);
3082     if (s->session->srp_username == NULL) {
3083         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3084         return 0;
3085     }
3086 
3087     if (!srp_generate_server_master_secret(s)) {
3088         /* SSLfatal() already called */
3089         return 0;
3090     }
3091 
3092     return 1;
3093 #else
3094     /* Should never happen */
3095     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3096     return 0;
3097 #endif
3098 }
3099 
3100 static int tls_process_cke_gost(SSL *s, PACKET *pkt)
3101 {
3102 #ifndef OPENSSL_NO_GOST
3103     EVP_PKEY_CTX *pkey_ctx;
3104     EVP_PKEY *client_pub_pkey = NULL, *pk = NULL;
3105     unsigned char premaster_secret[32];
3106     const unsigned char *start;
3107     size_t outlen = 32, inlen;
3108     unsigned long alg_a;
3109     GOST_KX_MESSAGE *pKX = NULL;
3110     const unsigned char *ptr;
3111     int ret = 0;
3112 
3113     /* Get our certificate private key */
3114     alg_a = s->s3.tmp.new_cipher->algorithm_auth;
3115     if (alg_a & SSL_aGOST12) {
3116         /*
3117          * New GOST ciphersuites have SSL_aGOST01 bit too
3118          */
3119         pk = s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey;
3120         if (pk == NULL) {
3121             pk = s->cert->pkeys[SSL_PKEY_GOST12_256].privatekey;
3122         }
3123         if (pk == NULL) {
3124             pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
3125         }
3126     } else if (alg_a & SSL_aGOST01) {
3127         pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
3128     }
3129 
3130     pkey_ctx = EVP_PKEY_CTX_new_from_pkey(s->ctx->libctx, pk, s->ctx->propq);
3131     if (pkey_ctx == NULL) {
3132         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3133         return 0;
3134     }
3135     if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) {
3136         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3137         goto err;
3138     }
3139     /*
3140      * If client certificate is present and is of the same type, maybe
3141      * use it for key exchange.  Don't mind errors from
3142      * EVP_PKEY_derive_set_peer, because it is completely valid to use a
3143      * client certificate for authorization only.
3144      */
3145     client_pub_pkey = X509_get0_pubkey(s->session->peer);
3146     if (client_pub_pkey) {
3147         if (EVP_PKEY_derive_set_peer(pkey_ctx, client_pub_pkey) <= 0)
3148             ERR_clear_error();
3149     }
3150 
3151     ptr = PACKET_data(pkt);
3152     /* Some implementations provide extra data in the opaqueBlob
3153      * We have nothing to do with this blob so we just skip it */
3154     pKX = d2i_GOST_KX_MESSAGE(NULL, &ptr, PACKET_remaining(pkt));
3155     if (pKX == NULL
3156        || pKX->kxBlob == NULL
3157        || ASN1_TYPE_get(pKX->kxBlob) != V_ASN1_SEQUENCE) {
3158          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DECRYPTION_FAILED);
3159          goto err;
3160     }
3161 
3162     if (!PACKET_forward(pkt, ptr - PACKET_data(pkt))) {
3163         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_DECRYPTION_FAILED);
3164         goto err;
3165     }
3166 
3167     if (PACKET_remaining(pkt) != 0) {
3168         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_DECRYPTION_FAILED);
3169         goto err;
3170     }
3171 
3172     inlen = pKX->kxBlob->value.sequence->length;
3173     start = pKX->kxBlob->value.sequence->data;
3174 
3175     if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, start,
3176                          inlen) <= 0) {
3177         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DECRYPTION_FAILED);
3178         goto err;
3179     }
3180     /* Generate master secret */
3181     if (!ssl_generate_master_secret(s, premaster_secret,
3182                                     sizeof(premaster_secret), 0)) {
3183         /* SSLfatal() already called */
3184         goto err;
3185     }
3186     /* Check if pubkey from client certificate was used */
3187     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2,
3188                           NULL) > 0)
3189         s->statem.no_cert_verify = 1;
3190 
3191     ret = 1;
3192  err:
3193     EVP_PKEY_CTX_free(pkey_ctx);
3194     GOST_KX_MESSAGE_free(pKX);
3195     return ret;
3196 #else
3197     /* Should never happen */
3198     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3199     return 0;
3200 #endif
3201 }
3202 
3203 static int tls_process_cke_gost18(SSL *s, PACKET *pkt)
3204 {
3205 #ifndef OPENSSL_NO_GOST
3206     unsigned char rnd_dgst[32];
3207     EVP_PKEY_CTX *pkey_ctx = NULL;
3208     EVP_PKEY *pk = NULL;
3209     unsigned char premaster_secret[32];
3210     const unsigned char *start = NULL;
3211     size_t outlen = 32, inlen = 0;
3212     int ret = 0;
3213     int cipher_nid = ossl_gost18_cke_cipher_nid(s);
3214 
3215     if (cipher_nid == NID_undef) {
3216         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3217         return 0;
3218     }
3219 
3220     if (ossl_gost_ukm(s, rnd_dgst) <= 0) {
3221         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3222         goto err;
3223     }
3224 
3225     /* Get our certificate private key */
3226     pk = s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey != NULL ?
3227          s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey :
3228          s->cert->pkeys[SSL_PKEY_GOST12_256].privatekey;
3229     if (pk == NULL) {
3230         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_STATE);
3231         goto err;
3232     }
3233 
3234     pkey_ctx = EVP_PKEY_CTX_new_from_pkey(s->ctx->libctx, pk, s->ctx->propq);
3235     if (pkey_ctx == NULL) {
3236         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3237         goto err;
3238     }
3239     if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) {
3240         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3241         goto err;
3242     }
3243 
3244     /* Reuse EVP_PKEY_CTRL_SET_IV, make choice in engine code depending on size */
3245     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_DECRYPT,
3246                           EVP_PKEY_CTRL_SET_IV, 32, rnd_dgst) <= 0) {
3247         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
3248         goto err;
3249     }
3250 
3251     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_DECRYPT,
3252                           EVP_PKEY_CTRL_CIPHER, cipher_nid, NULL) <= 0) {
3253         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
3254         goto err;
3255     }
3256     inlen = PACKET_remaining(pkt);
3257     start = PACKET_data(pkt);
3258 
3259     if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, start, inlen) <= 0) {
3260         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DECRYPTION_FAILED);
3261         goto err;
3262     }
3263     /* Generate master secret */
3264     if (!ssl_generate_master_secret(s, premaster_secret,
3265          sizeof(premaster_secret), 0)) {
3266          /* SSLfatal() already called */
3267          goto err;
3268     }
3269     ret = 1;
3270 
3271  err:
3272     EVP_PKEY_CTX_free(pkey_ctx);
3273     return ret;
3274 #else
3275     /* Should never happen */
3276     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3277     return 0;
3278 #endif
3279 }
3280 
3281 MSG_PROCESS_RETURN tls_process_client_key_exchange(SSL *s, PACKET *pkt)
3282 {
3283     unsigned long alg_k;
3284 
3285     alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
3286 
3287     /* For PSK parse and retrieve identity, obtain PSK key */
3288     if ((alg_k & SSL_PSK) && !tls_process_cke_psk_preamble(s, pkt)) {
3289         /* SSLfatal() already called */
3290         goto err;
3291     }
3292 
3293     if (alg_k & SSL_kPSK) {
3294         /* Identity extracted earlier: should be nothing left */
3295         if (PACKET_remaining(pkt) != 0) {
3296             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3297             goto err;
3298         }
3299         /* PSK handled by ssl_generate_master_secret */
3300         if (!ssl_generate_master_secret(s, NULL, 0, 0)) {
3301             /* SSLfatal() already called */
3302             goto err;
3303         }
3304     } else if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) {
3305         if (!tls_process_cke_rsa(s, pkt)) {
3306             /* SSLfatal() already called */
3307             goto err;
3308         }
3309     } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
3310         if (!tls_process_cke_dhe(s, pkt)) {
3311             /* SSLfatal() already called */
3312             goto err;
3313         }
3314     } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
3315         if (!tls_process_cke_ecdhe(s, pkt)) {
3316             /* SSLfatal() already called */
3317             goto err;
3318         }
3319     } else if (alg_k & SSL_kSRP) {
3320         if (!tls_process_cke_srp(s, pkt)) {
3321             /* SSLfatal() already called */
3322             goto err;
3323         }
3324     } else if (alg_k & SSL_kGOST) {
3325         if (!tls_process_cke_gost(s, pkt)) {
3326             /* SSLfatal() already called */
3327             goto err;
3328         }
3329     } else if (alg_k & SSL_kGOST18) {
3330         if (!tls_process_cke_gost18(s, pkt)) {
3331             /* SSLfatal() already called */
3332             goto err;
3333         }
3334     } else {
3335         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_UNKNOWN_CIPHER_TYPE);
3336         goto err;
3337     }
3338 
3339     return MSG_PROCESS_CONTINUE_PROCESSING;
3340  err:
3341 #ifndef OPENSSL_NO_PSK
3342     OPENSSL_clear_free(s->s3.tmp.psk, s->s3.tmp.psklen);
3343     s->s3.tmp.psk = NULL;
3344     s->s3.tmp.psklen = 0;
3345 #endif
3346     return MSG_PROCESS_ERROR;
3347 }
3348 
3349 WORK_STATE tls_post_process_client_key_exchange(SSL *s, WORK_STATE wst)
3350 {
3351 #ifndef OPENSSL_NO_SCTP
3352     if (wst == WORK_MORE_A) {
3353         if (SSL_IS_DTLS(s)) {
3354             unsigned char sctpauthkey[64];
3355             char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
3356             size_t labellen;
3357             /*
3358              * Add new shared key for SCTP-Auth, will be ignored if no SCTP
3359              * used.
3360              */
3361             memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
3362                    sizeof(DTLS1_SCTP_AUTH_LABEL));
3363 
3364             /* Don't include the terminating zero. */
3365             labellen = sizeof(labelbuffer) - 1;
3366             if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
3367                 labellen += 1;
3368 
3369             if (SSL_export_keying_material(s, sctpauthkey,
3370                                            sizeof(sctpauthkey), labelbuffer,
3371                                            labellen, NULL, 0,
3372                                            0) <= 0) {
3373                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3374                 return WORK_ERROR;
3375             }
3376 
3377             BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
3378                      sizeof(sctpauthkey), sctpauthkey);
3379         }
3380     }
3381 #endif
3382 
3383     if (s->statem.no_cert_verify || !s->session->peer) {
3384         /*
3385          * No certificate verify or no peer certificate so we no longer need
3386          * the handshake_buffer
3387          */
3388         if (!ssl3_digest_cached_records(s, 0)) {
3389             /* SSLfatal() already called */
3390             return WORK_ERROR;
3391         }
3392         return WORK_FINISHED_CONTINUE;
3393     } else {
3394         if (!s->s3.handshake_buffer) {
3395             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3396             return WORK_ERROR;
3397         }
3398         /*
3399          * For sigalgs freeze the handshake buffer. If we support
3400          * extms we've done this already so this is a no-op
3401          */
3402         if (!ssl3_digest_cached_records(s, 1)) {
3403             /* SSLfatal() already called */
3404             return WORK_ERROR;
3405         }
3406     }
3407 
3408     return WORK_FINISHED_CONTINUE;
3409 }
3410 
3411 MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt)
3412 {
3413     int i;
3414     MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;
3415     X509 *x = NULL;
3416     unsigned long l;
3417     const unsigned char *certstart, *certbytes;
3418     STACK_OF(X509) *sk = NULL;
3419     PACKET spkt, context;
3420     size_t chainidx;
3421     SSL_SESSION *new_sess = NULL;
3422 
3423     /*
3424      * To get this far we must have read encrypted data from the client. We no
3425      * longer tolerate unencrypted alerts. This value is ignored if less than
3426      * TLSv1.3
3427      */
3428     s->statem.enc_read_state = ENC_READ_STATE_VALID;
3429 
3430     if ((sk = sk_X509_new_null()) == NULL) {
3431         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3432         goto err;
3433     }
3434 
3435     if (SSL_IS_TLS13(s) && (!PACKET_get_length_prefixed_1(pkt, &context)
3436                             || (s->pha_context == NULL && PACKET_remaining(&context) != 0)
3437                             || (s->pha_context != NULL &&
3438                                 !PACKET_equal(&context, s->pha_context, s->pha_context_len)))) {
3439         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_INVALID_CONTEXT);
3440         goto err;
3441     }
3442 
3443     if (!PACKET_get_length_prefixed_3(pkt, &spkt)
3444             || PACKET_remaining(pkt) != 0) {
3445         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3446         goto err;
3447     }
3448 
3449     for (chainidx = 0; PACKET_remaining(&spkt) > 0; chainidx++) {
3450         if (!PACKET_get_net_3(&spkt, &l)
3451             || !PACKET_get_bytes(&spkt, &certbytes, l)) {
3452             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_CERT_LENGTH_MISMATCH);
3453             goto err;
3454         }
3455 
3456         certstart = certbytes;
3457         x = X509_new_ex(s->ctx->libctx, s->ctx->propq);
3458         if (x == NULL) {
3459             SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_MALLOC_FAILURE);
3460             goto err;
3461         }
3462         if (d2i_X509(&x, (const unsigned char **)&certbytes, l) == NULL) {
3463             SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_ASN1_LIB);
3464             goto err;
3465         }
3466 
3467         if (certbytes != (certstart + l)) {
3468             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_CERT_LENGTH_MISMATCH);
3469             goto err;
3470         }
3471 
3472         if (SSL_IS_TLS13(s)) {
3473             RAW_EXTENSION *rawexts = NULL;
3474             PACKET extensions;
3475 
3476             if (!PACKET_get_length_prefixed_2(&spkt, &extensions)) {
3477                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
3478                 goto err;
3479             }
3480             if (!tls_collect_extensions(s, &extensions,
3481                                         SSL_EXT_TLS1_3_CERTIFICATE, &rawexts,
3482                                         NULL, chainidx == 0)
3483                 || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE,
3484                                              rawexts, x, chainidx,
3485                                              PACKET_remaining(&spkt) == 0)) {
3486                 OPENSSL_free(rawexts);
3487                 goto err;
3488             }
3489             OPENSSL_free(rawexts);
3490         }
3491 
3492         if (!sk_X509_push(sk, x)) {
3493             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3494             goto err;
3495         }
3496         x = NULL;
3497     }
3498 
3499     if (sk_X509_num(sk) <= 0) {
3500         /* TLS does not mind 0 certs returned */
3501         if (s->version == SSL3_VERSION) {
3502             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3503                      SSL_R_NO_CERTIFICATES_RETURNED);
3504             goto err;
3505         }
3506         /* Fail for TLS only if we required a certificate */
3507         else if ((s->verify_mode & SSL_VERIFY_PEER) &&
3508                  (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) {
3509             SSLfatal(s, SSL_AD_CERTIFICATE_REQUIRED,
3510                      SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
3511             goto err;
3512         }
3513         /* No client certificate so digest cached records */
3514         if (s->s3.handshake_buffer && !ssl3_digest_cached_records(s, 0)) {
3515             /* SSLfatal() already called */
3516             goto err;
3517         }
3518     } else {
3519         EVP_PKEY *pkey;
3520         i = ssl_verify_cert_chain(s, sk);
3521         if (i <= 0) {
3522             SSLfatal(s, ssl_x509err2alert(s->verify_result),
3523                      SSL_R_CERTIFICATE_VERIFY_FAILED);
3524             goto err;
3525         }
3526         pkey = X509_get0_pubkey(sk_X509_value(sk, 0));
3527         if (pkey == NULL) {
3528             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3529                      SSL_R_UNKNOWN_CERTIFICATE_TYPE);
3530             goto err;
3531         }
3532     }
3533 
3534     /*
3535      * Sessions must be immutable once they go into the session cache. Otherwise
3536      * we can get multi-thread problems. Therefore we don't "update" sessions,
3537      * we replace them with a duplicate. Here, we need to do this every time
3538      * a new certificate is received via post-handshake authentication, as the
3539      * session may have already gone into the session cache.
3540      */
3541 
3542     if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
3543         if ((new_sess = ssl_session_dup(s->session, 0)) == 0) {
3544             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3545             goto err;
3546         }
3547 
3548         SSL_SESSION_free(s->session);
3549         s->session = new_sess;
3550     }
3551 
3552     X509_free(s->session->peer);
3553     s->session->peer = sk_X509_shift(sk);
3554     s->session->verify_result = s->verify_result;
3555 
3556     sk_X509_pop_free(s->session->peer_chain, X509_free);
3557     s->session->peer_chain = sk;
3558     sk = NULL;
3559 
3560     /*
3561      * Freeze the handshake buffer. For <TLS1.3 we do this after the CKE
3562      * message
3563      */
3564     if (SSL_IS_TLS13(s) && !ssl3_digest_cached_records(s, 1)) {
3565         /* SSLfatal() already called */
3566         goto err;
3567     }
3568 
3569     /*
3570      * Inconsistency alert: cert_chain does *not* include the peer's own
3571      * certificate, while we do include it in statem_clnt.c
3572      */
3573 
3574     /* Save the current hash state for when we receive the CertificateVerify */
3575     if (SSL_IS_TLS13(s)) {
3576         if (!ssl_handshake_hash(s, s->cert_verify_hash,
3577                                 sizeof(s->cert_verify_hash),
3578                                 &s->cert_verify_hash_len)) {
3579             /* SSLfatal() already called */
3580             goto err;
3581         }
3582 
3583         /* Resend session tickets */
3584         s->sent_tickets = 0;
3585     }
3586 
3587     ret = MSG_PROCESS_CONTINUE_READING;
3588 
3589  err:
3590     X509_free(x);
3591     sk_X509_pop_free(sk, X509_free);
3592     return ret;
3593 }
3594 
3595 int tls_construct_server_certificate(SSL *s, WPACKET *pkt)
3596 {
3597     CERT_PKEY *cpk = s->s3.tmp.cert;
3598 
3599     if (cpk == NULL) {
3600         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3601         return 0;
3602     }
3603 
3604     /*
3605      * In TLSv1.3 the certificate chain is always preceded by a 0 length context
3606      * for the server Certificate message
3607      */
3608     if (SSL_IS_TLS13(s) && !WPACKET_put_bytes_u8(pkt, 0)) {
3609         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3610         return 0;
3611     }
3612     if (!ssl3_output_cert_chain(s, pkt, cpk)) {
3613         /* SSLfatal() already called */
3614         return 0;
3615     }
3616 
3617     return 1;
3618 }
3619 
3620 static int create_ticket_prequel(SSL *s, WPACKET *pkt, uint32_t age_add,
3621                                  unsigned char *tick_nonce)
3622 {
3623     uint32_t timeout = (uint32_t)s->session->timeout;
3624 
3625     /*
3626      * Ticket lifetime hint:
3627      * In TLSv1.3 we reset the "time" field above, and always specify the
3628      * timeout, limited to a 1 week period per RFC8446.
3629      * For TLSv1.2 this is advisory only and we leave this unspecified for
3630      * resumed session (for simplicity).
3631      */
3632 #define ONE_WEEK_SEC (7 * 24 * 60 * 60)
3633 
3634     if (SSL_IS_TLS13(s)) {
3635         if (s->session->timeout > ONE_WEEK_SEC)
3636             timeout = ONE_WEEK_SEC;
3637     } else if (s->hit)
3638         timeout = 0;
3639 
3640     if (!WPACKET_put_bytes_u32(pkt, timeout)) {
3641         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3642         return 0;
3643     }
3644 
3645     if (SSL_IS_TLS13(s)) {
3646         if (!WPACKET_put_bytes_u32(pkt, age_add)
3647                 || !WPACKET_sub_memcpy_u8(pkt, tick_nonce, TICKET_NONCE_SIZE)) {
3648             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3649             return 0;
3650         }
3651     }
3652 
3653     /* Start the sub-packet for the actual ticket data */
3654     if (!WPACKET_start_sub_packet_u16(pkt)) {
3655         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3656         return 0;
3657     }
3658 
3659     return 1;
3660 }
3661 
3662 /*
3663  * Returns 1 on success, 0 to abort construction of the ticket (non-fatal), or
3664  * -1 on fatal error
3665  */
3666 static int construct_stateless_ticket(SSL *s, WPACKET *pkt, uint32_t age_add,
3667                                       unsigned char *tick_nonce)
3668 {
3669     unsigned char *senc = NULL;
3670     EVP_CIPHER_CTX *ctx = NULL;
3671     SSL_HMAC *hctx = NULL;
3672     unsigned char *p, *encdata1, *encdata2, *macdata1, *macdata2;
3673     const unsigned char *const_p;
3674     int len, slen_full, slen, lenfinal;
3675     SSL_SESSION *sess;
3676     size_t hlen;
3677     SSL_CTX *tctx = s->session_ctx;
3678     unsigned char iv[EVP_MAX_IV_LENGTH];
3679     unsigned char key_name[TLSEXT_KEYNAME_LENGTH];
3680     int iv_len, ok = -1;
3681     size_t macoffset, macendoffset;
3682 
3683     /* get session encoding length */
3684     slen_full = i2d_SSL_SESSION(s->session, NULL);
3685     /*
3686      * Some length values are 16 bits, so forget it if session is too
3687      * long
3688      */
3689     if (slen_full == 0 || slen_full > 0xFF00) {
3690         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3691         goto err;
3692     }
3693     senc = OPENSSL_malloc(slen_full);
3694     if (senc == NULL) {
3695         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3696         goto err;
3697     }
3698 
3699     ctx = EVP_CIPHER_CTX_new();
3700     hctx = ssl_hmac_new(tctx);
3701     if (ctx == NULL || hctx == NULL) {
3702         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3703         goto err;
3704     }
3705 
3706     p = senc;
3707     if (!i2d_SSL_SESSION(s->session, &p)) {
3708         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3709         goto err;
3710     }
3711 
3712     /*
3713      * create a fresh copy (not shared with other threads) to clean up
3714      */
3715     const_p = senc;
3716     sess = d2i_SSL_SESSION(NULL, &const_p, slen_full);
3717     if (sess == NULL) {
3718         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3719         goto err;
3720     }
3721 
3722     slen = i2d_SSL_SESSION(sess, NULL);
3723     if (slen == 0 || slen > slen_full) {
3724         /* shouldn't ever happen */
3725         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3726         SSL_SESSION_free(sess);
3727         goto err;
3728     }
3729     p = senc;
3730     if (!i2d_SSL_SESSION(sess, &p)) {
3731         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3732         SSL_SESSION_free(sess);
3733         goto err;
3734     }
3735     SSL_SESSION_free(sess);
3736 
3737     /*
3738      * Initialize HMAC and cipher contexts. If callback present it does
3739      * all the work otherwise use generated values from parent ctx.
3740      */
3741 #ifndef OPENSSL_NO_DEPRECATED_3_0
3742     if (tctx->ext.ticket_key_evp_cb != NULL || tctx->ext.ticket_key_cb != NULL)
3743 #else
3744     if (tctx->ext.ticket_key_evp_cb != NULL)
3745 #endif
3746     {
3747         int ret = 0;
3748 
3749         if (tctx->ext.ticket_key_evp_cb != NULL)
3750             ret = tctx->ext.ticket_key_evp_cb(s, key_name, iv, ctx,
3751                                               ssl_hmac_get0_EVP_MAC_CTX(hctx),
3752                                               1);
3753 #ifndef OPENSSL_NO_DEPRECATED_3_0
3754         else if (tctx->ext.ticket_key_cb != NULL)
3755             /* if 0 is returned, write an empty ticket */
3756             ret = tctx->ext.ticket_key_cb(s, key_name, iv, ctx,
3757                                           ssl_hmac_get0_HMAC_CTX(hctx), 1);
3758 #endif
3759 
3760         if (ret == 0) {
3761             /*
3762              * In TLSv1.2 we construct a 0 length ticket. In TLSv1.3 a 0
3763              * length ticket is not allowed so we abort construction of the
3764              * ticket
3765              */
3766             if (SSL_IS_TLS13(s)) {
3767                 ok = 0;
3768                 goto err;
3769             }
3770             /* Put timeout and length */
3771             if (!WPACKET_put_bytes_u32(pkt, 0)
3772                     || !WPACKET_put_bytes_u16(pkt, 0)) {
3773                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3774                 goto err;
3775             }
3776             OPENSSL_free(senc);
3777             EVP_CIPHER_CTX_free(ctx);
3778             ssl_hmac_free(hctx);
3779             return 1;
3780         }
3781         if (ret < 0) {
3782             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_CALLBACK_FAILED);
3783             goto err;
3784         }
3785         iv_len = EVP_CIPHER_CTX_get_iv_length(ctx);
3786         if (iv_len < 0) {
3787             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3788             goto err;
3789         }
3790     } else {
3791         EVP_CIPHER *cipher = EVP_CIPHER_fetch(s->ctx->libctx, "AES-256-CBC",
3792                                               s->ctx->propq);
3793 
3794         if (cipher == NULL) {
3795             /* Error is already recorded */
3796             SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
3797             goto err;
3798         }
3799 
3800         iv_len = EVP_CIPHER_get_iv_length(cipher);
3801         if (iv_len < 0
3802                 || RAND_bytes_ex(s->ctx->libctx, iv, iv_len, 0) <= 0
3803                 || !EVP_EncryptInit_ex(ctx, cipher, NULL,
3804                                        tctx->ext.secure->tick_aes_key, iv)
3805                 || !ssl_hmac_init(hctx, tctx->ext.secure->tick_hmac_key,
3806                                   sizeof(tctx->ext.secure->tick_hmac_key),
3807                                   "SHA256")) {
3808             EVP_CIPHER_free(cipher);
3809             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3810             goto err;
3811         }
3812         EVP_CIPHER_free(cipher);
3813         memcpy(key_name, tctx->ext.tick_key_name,
3814                sizeof(tctx->ext.tick_key_name));
3815     }
3816 
3817     if (!create_ticket_prequel(s, pkt, age_add, tick_nonce)) {
3818         /* SSLfatal() already called */
3819         goto err;
3820     }
3821 
3822     if (!WPACKET_get_total_written(pkt, &macoffset)
3823                /* Output key name */
3824             || !WPACKET_memcpy(pkt, key_name, sizeof(key_name))
3825                /* output IV */
3826             || !WPACKET_memcpy(pkt, iv, iv_len)
3827             || !WPACKET_reserve_bytes(pkt, slen + EVP_MAX_BLOCK_LENGTH,
3828                                       &encdata1)
3829                /* Encrypt session data */
3830             || !EVP_EncryptUpdate(ctx, encdata1, &len, senc, slen)
3831             || !WPACKET_allocate_bytes(pkt, len, &encdata2)
3832             || encdata1 != encdata2
3833             || !EVP_EncryptFinal(ctx, encdata1 + len, &lenfinal)
3834             || !WPACKET_allocate_bytes(pkt, lenfinal, &encdata2)
3835             || encdata1 + len != encdata2
3836             || len + lenfinal > slen + EVP_MAX_BLOCK_LENGTH
3837             || !WPACKET_get_total_written(pkt, &macendoffset)
3838             || !ssl_hmac_update(hctx,
3839                                 (unsigned char *)s->init_buf->data + macoffset,
3840                                 macendoffset - macoffset)
3841             || !WPACKET_reserve_bytes(pkt, EVP_MAX_MD_SIZE, &macdata1)
3842             || !ssl_hmac_final(hctx, macdata1, &hlen, EVP_MAX_MD_SIZE)
3843             || hlen > EVP_MAX_MD_SIZE
3844             || !WPACKET_allocate_bytes(pkt, hlen, &macdata2)
3845             || macdata1 != macdata2) {
3846         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3847         goto err;
3848     }
3849 
3850     /* Close the sub-packet created by create_ticket_prequel() */
3851     if (!WPACKET_close(pkt)) {
3852         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3853         goto err;
3854     }
3855 
3856     ok = 1;
3857  err:
3858     OPENSSL_free(senc);
3859     EVP_CIPHER_CTX_free(ctx);
3860     ssl_hmac_free(hctx);
3861     return ok;
3862 }
3863 
3864 static int construct_stateful_ticket(SSL *s, WPACKET *pkt, uint32_t age_add,
3865                                      unsigned char *tick_nonce)
3866 {
3867     if (!create_ticket_prequel(s, pkt, age_add, tick_nonce)) {
3868         /* SSLfatal() already called */
3869         return 0;
3870     }
3871 
3872     if (!WPACKET_memcpy(pkt, s->session->session_id,
3873                         s->session->session_id_length)
3874             || !WPACKET_close(pkt)) {
3875         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3876         return 0;
3877     }
3878 
3879     return 1;
3880 }
3881 
3882 static void tls_update_ticket_counts(SSL *s)
3883 {
3884     /*
3885      * Increment both |sent_tickets| and |next_ticket_nonce|. |sent_tickets|
3886      * gets reset to 0 if we send more tickets following a post-handshake
3887      * auth, but |next_ticket_nonce| does not.  If we're sending extra
3888      * tickets, decrement the count of pending extra tickets.
3889      */
3890     s->sent_tickets++;
3891     s->next_ticket_nonce++;
3892     if (s->ext.extra_tickets_expected > 0)
3893         s->ext.extra_tickets_expected--;
3894 }
3895 
3896 int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
3897 {
3898     SSL_CTX *tctx = s->session_ctx;
3899     unsigned char tick_nonce[TICKET_NONCE_SIZE];
3900     union {
3901         unsigned char age_add_c[sizeof(uint32_t)];
3902         uint32_t age_add;
3903     } age_add_u;
3904     int ret = 0;
3905 
3906     age_add_u.age_add = 0;
3907 
3908     if (SSL_IS_TLS13(s)) {
3909         size_t i, hashlen;
3910         uint64_t nonce;
3911         static const unsigned char nonce_label[] = "resumption";
3912         const EVP_MD *md = ssl_handshake_md(s);
3913         int hashleni = EVP_MD_get_size(md);
3914 
3915         /* Ensure cast to size_t is safe */
3916         if (!ossl_assert(hashleni >= 0)) {
3917             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3918             goto err;
3919         }
3920         hashlen = (size_t)hashleni;
3921 
3922         /*
3923          * If we already sent one NewSessionTicket, or we resumed then
3924          * s->session may already be in a cache and so we must not modify it.
3925          * Instead we need to take a copy of it and modify that.
3926          */
3927         if (s->sent_tickets != 0 || s->hit) {
3928             SSL_SESSION *new_sess = ssl_session_dup(s->session, 0);
3929 
3930             if (new_sess == NULL) {
3931                 /* SSLfatal already called */
3932                 goto err;
3933             }
3934 
3935             SSL_SESSION_free(s->session);
3936             s->session = new_sess;
3937         }
3938 
3939         if (!ssl_generate_session_id(s, s->session)) {
3940             /* SSLfatal() already called */
3941             goto err;
3942         }
3943         if (RAND_bytes_ex(s->ctx->libctx, age_add_u.age_add_c,
3944                           sizeof(age_add_u), 0) <= 0) {
3945             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3946             goto err;
3947         }
3948         s->session->ext.tick_age_add = age_add_u.age_add;
3949 
3950         nonce = s->next_ticket_nonce;
3951         for (i = TICKET_NONCE_SIZE; i > 0; i--) {
3952             tick_nonce[i - 1] = (unsigned char)(nonce & 0xff);
3953             nonce >>= 8;
3954         }
3955 
3956         if (!tls13_hkdf_expand(s, md, s->resumption_master_secret,
3957                                nonce_label,
3958                                sizeof(nonce_label) - 1,
3959                                tick_nonce,
3960                                TICKET_NONCE_SIZE,
3961                                s->session->master_key,
3962                                hashlen, 1)) {
3963             /* SSLfatal() already called */
3964             goto err;
3965         }
3966         s->session->master_key_length = hashlen;
3967 
3968         s->session->time = time(NULL);
3969         ssl_session_calculate_timeout(s->session);
3970         if (s->s3.alpn_selected != NULL) {
3971             OPENSSL_free(s->session->ext.alpn_selected);
3972             s->session->ext.alpn_selected =
3973                 OPENSSL_memdup(s->s3.alpn_selected, s->s3.alpn_selected_len);
3974             if (s->session->ext.alpn_selected == NULL) {
3975                 s->session->ext.alpn_selected_len = 0;
3976                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3977                 goto err;
3978             }
3979             s->session->ext.alpn_selected_len = s->s3.alpn_selected_len;
3980         }
3981         s->session->ext.max_early_data = s->max_early_data;
3982     }
3983 
3984     if (tctx->generate_ticket_cb != NULL &&
3985         tctx->generate_ticket_cb(s, tctx->ticket_cb_data) == 0) {
3986         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3987         goto err;
3988     }
3989     /*
3990      * If we are using anti-replay protection then we behave as if
3991      * SSL_OP_NO_TICKET is set - we are caching tickets anyway so there
3992      * is no point in using full stateless tickets.
3993      */
3994     if (SSL_IS_TLS13(s)
3995             && ((s->options & SSL_OP_NO_TICKET) != 0
3996                 || (s->max_early_data > 0
3997                     && (s->options & SSL_OP_NO_ANTI_REPLAY) == 0))) {
3998         if (!construct_stateful_ticket(s, pkt, age_add_u.age_add, tick_nonce)) {
3999             /* SSLfatal() already called */
4000             goto err;
4001         }
4002     } else {
4003         int tmpret;
4004 
4005         tmpret = construct_stateless_ticket(s, pkt, age_add_u.age_add,
4006                                             tick_nonce);
4007         if (tmpret != 1) {
4008             if (tmpret == 0) {
4009                 ret = 2; /* Non-fatal. Abort construction but continue */
4010                 /* We count this as a success so update the counts anwyay */
4011                 tls_update_ticket_counts(s);
4012             }
4013             /* else SSLfatal() already called */
4014             goto err;
4015         }
4016     }
4017 
4018     if (SSL_IS_TLS13(s)) {
4019         if (!tls_construct_extensions(s, pkt,
4020                                       SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
4021                                       NULL, 0)) {
4022             /* SSLfatal() already called */
4023             goto err;
4024         }
4025         tls_update_ticket_counts(s);
4026         ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
4027     }
4028 
4029     ret = 1;
4030  err:
4031     return ret;
4032 }
4033 
4034 /*
4035  * In TLSv1.3 this is called from the extensions code, otherwise it is used to
4036  * create a separate message. Returns 1 on success or 0 on failure.
4037  */
4038 int tls_construct_cert_status_body(SSL *s, WPACKET *pkt)
4039 {
4040     if (!WPACKET_put_bytes_u8(pkt, s->ext.status_type)
4041             || !WPACKET_sub_memcpy_u24(pkt, s->ext.ocsp.resp,
4042                                        s->ext.ocsp.resp_len)) {
4043         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4044         return 0;
4045     }
4046 
4047     return 1;
4048 }
4049 
4050 int tls_construct_cert_status(SSL *s, WPACKET *pkt)
4051 {
4052     if (!tls_construct_cert_status_body(s, pkt)) {
4053         /* SSLfatal() already called */
4054         return 0;
4055     }
4056 
4057     return 1;
4058 }
4059 
4060 #ifndef OPENSSL_NO_NEXTPROTONEG
4061 /*
4062  * tls_process_next_proto reads a Next Protocol Negotiation handshake message.
4063  * It sets the next_proto member in s if found
4064  */
4065 MSG_PROCESS_RETURN tls_process_next_proto(SSL *s, PACKET *pkt)
4066 {
4067     PACKET next_proto, padding;
4068     size_t next_proto_len;
4069 
4070     /*-
4071      * The payload looks like:
4072      *   uint8 proto_len;
4073      *   uint8 proto[proto_len];
4074      *   uint8 padding_len;
4075      *   uint8 padding[padding_len];
4076      */
4077     if (!PACKET_get_length_prefixed_1(pkt, &next_proto)
4078         || !PACKET_get_length_prefixed_1(pkt, &padding)
4079         || PACKET_remaining(pkt) > 0) {
4080         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
4081         return MSG_PROCESS_ERROR;
4082     }
4083 
4084     if (!PACKET_memdup(&next_proto, &s->ext.npn, &next_proto_len)) {
4085         s->ext.npn_len = 0;
4086         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4087         return MSG_PROCESS_ERROR;
4088     }
4089 
4090     s->ext.npn_len = (unsigned char)next_proto_len;
4091 
4092     return MSG_PROCESS_CONTINUE_READING;
4093 }
4094 #endif
4095 
4096 static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt)
4097 {
4098     if (!tls_construct_extensions(s, pkt, SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
4099                                   NULL, 0)) {
4100         /* SSLfatal() already called */
4101         return 0;
4102     }
4103 
4104     return 1;
4105 }
4106 
4107 MSG_PROCESS_RETURN tls_process_end_of_early_data(SSL *s, PACKET *pkt)
4108 {
4109     if (PACKET_remaining(pkt) != 0) {
4110         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
4111         return MSG_PROCESS_ERROR;
4112     }
4113 
4114     if (s->early_data_state != SSL_EARLY_DATA_READING
4115             && s->early_data_state != SSL_EARLY_DATA_READ_RETRY) {
4116         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4117         return MSG_PROCESS_ERROR;
4118     }
4119 
4120     /*
4121      * EndOfEarlyData signals a key change so the end of the message must be on
4122      * a record boundary.
4123      */
4124     if (RECORD_LAYER_processed_read_pending(&s->rlayer)) {
4125         SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_NOT_ON_RECORD_BOUNDARY);
4126         return MSG_PROCESS_ERROR;
4127     }
4128 
4129     s->early_data_state = SSL_EARLY_DATA_FINISHED_READING;
4130     if (!s->method->ssl3_enc->change_cipher_state(s,
4131                 SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_READ)) {
4132         /* SSLfatal() already called */
4133         return MSG_PROCESS_ERROR;
4134     }
4135 
4136     return MSG_PROCESS_CONTINUE_READING;
4137 }
4138