xref: /freebsd/crypto/openssl/ssl/statem/statem_srvr.c (revision 1523ccfd9c8c254f7928143d31c305384b05fd11)
1 /*
2  * Copyright 1995-2026 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 "internal/e_os.h"
13 
14 #include <stdio.h>
15 #include "../ssl_local.h"
16 #include "statem_local.h"
17 #include "internal/constant_time.h"
18 #include "internal/cryptlib.h"
19 #include "internal/ssl_unwrap.h"
20 #include <openssl/buffer.h>
21 #include <openssl/rand.h>
22 #include <openssl/objects.h>
23 #include <openssl/evp.h>
24 #include <openssl/x509.h>
25 #include <openssl/dh.h>
26 #include <openssl/rsa.h>
27 #include <openssl/bn.h>
28 #include <openssl/md5.h>
29 #include <openssl/trace.h>
30 #include <openssl/core_names.h>
31 #include <openssl/asn1t.h>
32 #include <openssl/comp.h>
33 #include "internal/comp.h"
34 
35 #define TICKET_NONCE_SIZE 8
36 
37 typedef struct {
38     ASN1_TYPE *kxBlob;
39     ASN1_TYPE *opaqueBlob;
40 } GOST_KX_MESSAGE;
41 
42 DECLARE_ASN1_FUNCTIONS(GOST_KX_MESSAGE)
43 
44 ASN1_SEQUENCE(GOST_KX_MESSAGE) = {
45     ASN1_SIMPLE(GOST_KX_MESSAGE, kxBlob, ASN1_ANY),
46     ASN1_OPT(GOST_KX_MESSAGE, opaqueBlob, ASN1_ANY),
47 } ASN1_SEQUENCE_END(GOST_KX_MESSAGE)
48 
49 IMPLEMENT_ASN1_FUNCTIONS(GOST_KX_MESSAGE)
50 
51 static CON_FUNC_RETURN tls_construct_encrypted_extensions(SSL_CONNECTION *s,
52     WPACKET *pkt);
53 
received_client_cert(const SSL_CONNECTION * sc)54 static ossl_inline int received_client_cert(const SSL_CONNECTION *sc)
55 {
56     return sc->session->peer_rpk != NULL || sc->session->peer != NULL;
57 }
58 
59 /*
60  * ossl_statem_server13_read_transition() encapsulates the logic for the allowed
61  * handshake state transitions when a TLSv1.3 server is reading messages from
62  * the client. The message type that the client has sent is provided in |mt|.
63  * The current state is in |s->statem.hand_state|.
64  *
65  * Return values are 1 for success (transition allowed) and  0 on error
66  * (transition not allowed)
67  */
ossl_statem_server13_read_transition(SSL_CONNECTION * s,int mt)68 static int ossl_statem_server13_read_transition(SSL_CONNECTION *s, int mt)
69 {
70     OSSL_STATEM *st = &s->statem;
71 
72     /*
73      * Note: There is no case for TLS_ST_BEFORE because at that stage we have
74      * not negotiated TLSv1.3 yet, so that case is handled by
75      * ossl_statem_server_read_transition()
76      */
77     switch (st->hand_state) {
78     default:
79         break;
80 
81     case TLS_ST_EARLY_DATA:
82         if (s->hello_retry_request == SSL_HRR_PENDING) {
83             if (mt == SSL3_MT_CLIENT_HELLO) {
84                 st->hand_state = TLS_ST_SR_CLNT_HELLO;
85                 return 1;
86             }
87             break;
88         } else if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED
89             && !SSL_NO_EOED(s)) {
90             if (mt == SSL3_MT_END_OF_EARLY_DATA) {
91                 st->hand_state = TLS_ST_SR_END_OF_EARLY_DATA;
92                 return 1;
93             }
94             break;
95         }
96         /* Fall through */
97 
98     case TLS_ST_SR_END_OF_EARLY_DATA:
99     case TLS_ST_SW_FINISHED:
100         if (s->s3.tmp.cert_request) {
101             if (mt == SSL3_MT_CERTIFICATE) {
102                 st->hand_state = TLS_ST_SR_CERT;
103                 return 1;
104             }
105 #ifndef OPENSSL_NO_COMP_ALG
106             if (mt == SSL3_MT_COMPRESSED_CERTIFICATE
107                 && s->ext.compress_certificate_sent) {
108                 st->hand_state = TLS_ST_SR_COMP_CERT;
109                 return 1;
110             }
111 #endif
112         } else {
113             if (mt == SSL3_MT_FINISHED) {
114                 st->hand_state = TLS_ST_SR_FINISHED;
115                 return 1;
116             }
117         }
118         break;
119 
120     case TLS_ST_SR_COMP_CERT:
121     case TLS_ST_SR_CERT:
122         if (!received_client_cert(s)) {
123             if (mt == SSL3_MT_FINISHED) {
124                 st->hand_state = TLS_ST_SR_FINISHED;
125                 return 1;
126             }
127         } else {
128             if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
129                 st->hand_state = TLS_ST_SR_CERT_VRFY;
130                 return 1;
131             }
132         }
133         break;
134 
135     case TLS_ST_SR_CERT_VRFY:
136         if (mt == SSL3_MT_FINISHED) {
137             st->hand_state = TLS_ST_SR_FINISHED;
138             return 1;
139         }
140         break;
141 
142     case TLS_ST_OK:
143         /*
144          * Its never ok to start processing handshake messages in the middle of
145          * early data (i.e. before we've received the end of early data alert)
146          */
147         if (s->early_data_state == SSL_EARLY_DATA_READING)
148             break;
149 
150         if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
151             if (mt == SSL3_MT_CERTIFICATE) {
152                 st->hand_state = TLS_ST_SR_CERT;
153                 return 1;
154             }
155 #ifndef OPENSSL_NO_COMP_ALG
156             if (mt == SSL3_MT_COMPRESSED_CERTIFICATE
157                 && s->ext.compress_certificate_sent) {
158                 st->hand_state = TLS_ST_SR_COMP_CERT;
159                 return 1;
160             }
161 #endif
162         }
163 
164         if (mt == SSL3_MT_KEY_UPDATE && !SSL_IS_QUIC_HANDSHAKE(s)) {
165             st->hand_state = TLS_ST_SR_KEY_UPDATE;
166             return 1;
167         }
168         break;
169     }
170 
171     /* No valid transition found */
172     return 0;
173 }
174 
175 /*
176  * ossl_statem_server_read_transition() encapsulates the logic for the allowed
177  * handshake state transitions when the server is reading messages from the
178  * client. The message type that the client has sent is provided in |mt|. The
179  * current state is in |s->statem.hand_state|.
180  *
181  * Return values are 1 for success (transition allowed) and  0 on error
182  * (transition not allowed)
183  */
ossl_statem_server_read_transition(SSL_CONNECTION * s,int mt)184 int ossl_statem_server_read_transition(SSL_CONNECTION *s, int mt)
185 {
186     OSSL_STATEM *st = &s->statem;
187 
188     if (SSL_CONNECTION_IS_TLS13(s)) {
189         if (!ossl_statem_server13_read_transition(s, mt))
190             goto err;
191         return 1;
192     }
193 
194     switch (st->hand_state) {
195     default:
196         break;
197 
198     case TLS_ST_BEFORE:
199     case TLS_ST_OK:
200     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
201         if (mt == SSL3_MT_CLIENT_HELLO) {
202             st->hand_state = TLS_ST_SR_CLNT_HELLO;
203             return 1;
204         }
205         break;
206 
207     case TLS_ST_SW_SRVR_DONE:
208         /*
209          * If we get a CKE message after a ServerDone then either
210          * 1) We didn't request a Certificate
211          * OR
212          * 2) If we did request one then
213          *      a) We allow no Certificate to be returned
214          *      AND
215          *      b) We are running SSL3 (in TLS1.0+ the client must return a 0
216          *         list if we requested a certificate)
217          */
218         if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) {
219             if (s->s3.tmp.cert_request) {
220                 if (s->version == SSL3_VERSION) {
221                     if ((s->verify_mode & SSL_VERIFY_PEER)
222                         && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) {
223                         /*
224                          * This isn't an unexpected message as such - we're just
225                          * not going to accept it because we require a client
226                          * cert.
227                          */
228                         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
229                             SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
230                         return 0;
231                     }
232                     st->hand_state = TLS_ST_SR_KEY_EXCH;
233                     return 1;
234                 }
235             } else {
236                 st->hand_state = TLS_ST_SR_KEY_EXCH;
237                 return 1;
238             }
239         } else if (s->s3.tmp.cert_request) {
240             if (mt == SSL3_MT_CERTIFICATE) {
241                 st->hand_state = TLS_ST_SR_CERT;
242                 return 1;
243             }
244         }
245         break;
246 
247     case TLS_ST_SR_CERT:
248         if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) {
249             st->hand_state = TLS_ST_SR_KEY_EXCH;
250             return 1;
251         }
252         break;
253 
254     case TLS_ST_SR_KEY_EXCH:
255         /*
256          * We should only process a CertificateVerify message if we have
257          * received a Certificate from the client. If so then |s->session->peer|
258          * will be non NULL. In some instances a CertificateVerify message is
259          * not required even if the peer has sent a Certificate (e.g. such as in
260          * the case of static DH). In that case |st->no_cert_verify| should be
261          * set.
262          */
263         if (!received_client_cert(s) || st->no_cert_verify) {
264             if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
265                 /*
266                  * For the ECDH ciphersuites when the client sends its ECDH
267                  * pub key in a certificate, the CertificateVerify message is
268                  * not sent. Also for GOST ciphersuites when the client uses
269                  * its key from the certificate for key exchange.
270                  */
271                 st->hand_state = TLS_ST_SR_CHANGE;
272                 return 1;
273             }
274         } else {
275             if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
276                 st->hand_state = TLS_ST_SR_CERT_VRFY;
277                 return 1;
278             }
279         }
280         break;
281 
282     case TLS_ST_SR_CERT_VRFY:
283         if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
284             st->hand_state = TLS_ST_SR_CHANGE;
285             return 1;
286         }
287         break;
288 
289     case TLS_ST_SR_CHANGE:
290 #ifndef OPENSSL_NO_NEXTPROTONEG
291         if (s->s3.npn_seen) {
292             if (mt == SSL3_MT_NEXT_PROTO) {
293                 st->hand_state = TLS_ST_SR_NEXT_PROTO;
294                 return 1;
295             }
296         } else {
297 #endif
298             if (mt == SSL3_MT_FINISHED) {
299                 st->hand_state = TLS_ST_SR_FINISHED;
300                 return 1;
301             }
302 #ifndef OPENSSL_NO_NEXTPROTONEG
303         }
304 #endif
305         break;
306 
307 #ifndef OPENSSL_NO_NEXTPROTONEG
308     case TLS_ST_SR_NEXT_PROTO:
309         if (mt == SSL3_MT_FINISHED) {
310             st->hand_state = TLS_ST_SR_FINISHED;
311             return 1;
312         }
313         break;
314 #endif
315 
316     case TLS_ST_SW_FINISHED:
317         if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
318             st->hand_state = TLS_ST_SR_CHANGE;
319             return 1;
320         }
321         break;
322     }
323 
324 err:
325     /* No valid transition found */
326     if (SSL_CONNECTION_IS_DTLS(s) && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
327         BIO *rbio;
328 
329         /*
330          * CCS messages don't have a message sequence number so this is probably
331          * because of an out-of-order CCS. We'll just drop it.
332          */
333         s->init_num = 0;
334         s->rwstate = SSL_READING;
335         rbio = SSL_get_rbio(SSL_CONNECTION_GET_SSL(s));
336         BIO_clear_retry_flags(rbio);
337         BIO_set_retry_read(rbio);
338         return 0;
339     }
340     SSLfatal(s, SSL3_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
341     return 0;
342 }
343 
344 /*
345  * Should we send a ServerKeyExchange message?
346  *
347  * Valid return values are:
348  *   1: Yes
349  *   0: No
350  */
send_server_key_exchange(SSL_CONNECTION * s)351 static int send_server_key_exchange(SSL_CONNECTION *s)
352 {
353     unsigned long alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
354 
355     /*
356      * only send a ServerKeyExchange if DH or fortezza but we have a
357      * sign only certificate PSK: may send PSK identity hints For
358      * ECC ciphersuites, we send a serverKeyExchange message only if
359      * the cipher suite is either ECDH-anon or ECDHE. In other cases,
360      * the server certificate contains the server's public key for
361      * key exchange.
362      */
363     if (alg_k & (SSL_kDHE | SSL_kECDHE)
364     /*
365      * PSK: send ServerKeyExchange if PSK identity hint if
366      * provided
367      */
368 #ifndef OPENSSL_NO_PSK
369         /* Only send SKE if we have identity hint for plain PSK */
370         || ((alg_k & (SSL_kPSK | SSL_kRSAPSK))
371             && s->cert->psk_identity_hint)
372         /* For other PSK always send SKE */
373         || (alg_k & (SSL_PSK & (SSL_kDHEPSK | SSL_kECDHEPSK)))
374 #endif
375 #ifndef OPENSSL_NO_SRP
376         /* SRP: send ServerKeyExchange */
377         || (alg_k & SSL_kSRP)
378 #endif
379     ) {
380         return 1;
381     }
382 
383     return 0;
384 }
385 
386 /*
387  * Used to determine if we should send a CompressedCertificate message
388  *
389  * Returns the algorithm to use, TLSEXT_comp_cert_none means no compression
390  */
get_compressed_certificate_alg(SSL_CONNECTION * sc)391 static int get_compressed_certificate_alg(SSL_CONNECTION *sc)
392 {
393 #ifndef OPENSSL_NO_COMP_ALG
394     int *alg = sc->ext.compress_certificate_from_peer;
395 
396     if (sc->s3.tmp.cert == NULL)
397         return TLSEXT_comp_cert_none;
398 
399     for (; *alg != TLSEXT_comp_cert_none; alg++) {
400         if (sc->s3.tmp.cert->comp_cert[*alg] != NULL)
401             return *alg;
402     }
403 #endif
404     return TLSEXT_comp_cert_none;
405 }
406 
407 /*
408  * Should we send a CertificateRequest message?
409  *
410  * Valid return values are:
411  *   1: Yes
412  *   0: No
413  */
send_certificate_request(SSL_CONNECTION * s)414 int send_certificate_request(SSL_CONNECTION *s)
415 {
416     if (
417         /* don't request cert unless asked for it: */
418         s->verify_mode & SSL_VERIFY_PEER
419         /*
420          * don't request if post-handshake-only unless doing
421          * post-handshake in TLSv1.3:
422          */
423         && (!SSL_CONNECTION_IS_TLS13(s)
424             || !(s->verify_mode & SSL_VERIFY_POST_HANDSHAKE)
425             || s->post_handshake_auth == SSL_PHA_REQUEST_PENDING)
426         /*
427          * if SSL_VERIFY_CLIENT_ONCE is set, don't request cert
428          * a second time:
429          */
430         && (s->certreqs_sent < 1 || !(s->verify_mode & SSL_VERIFY_CLIENT_ONCE))
431         /*
432          * never request cert in anonymous ciphersuites (see
433          * section "Certificate request" in SSL 3 drafts and in
434          * RFC 2246):
435          */
436         && (!(s->s3.tmp.new_cipher->algorithm_auth & SSL_aNULL)
437             /*
438              * ... except when the application insists on
439              * verification (against the specs, but statem_clnt.c accepts
440              * this for SSL 3)
441              */
442             || (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))
443         /* don't request certificate for SRP auth */
444         && !(s->s3.tmp.new_cipher->algorithm_auth & SSL_aSRP)
445         /*
446          * With normal PSK Certificates and Certificate Requests
447          * are omitted
448          */
449         && !(s->s3.tmp.new_cipher->algorithm_auth & SSL_aPSK)) {
450         return 1;
451     }
452 
453     return 0;
454 }
455 
do_compressed_cert(SSL_CONNECTION * sc)456 static int do_compressed_cert(SSL_CONNECTION *sc)
457 {
458     /* If we negotiated RPK, we won't attempt to compress it */
459     return sc->ext.server_cert_type == TLSEXT_cert_type_x509
460         && get_compressed_certificate_alg(sc) != TLSEXT_comp_cert_none;
461 }
462 
463 /*
464  * ossl_statem_server13_write_transition() works out what handshake state to
465  * move to next when a TLSv1.3 server is writing messages to be sent to the
466  * client.
467  */
ossl_statem_server13_write_transition(SSL_CONNECTION * s)468 static WRITE_TRAN ossl_statem_server13_write_transition(SSL_CONNECTION *s)
469 {
470     OSSL_STATEM *st = &s->statem;
471 
472     /*
473      * No case for TLS_ST_BEFORE, because at that stage we have not negotiated
474      * TLSv1.3 yet, so that is handled by ossl_statem_server_write_transition()
475      */
476 
477     switch (st->hand_state) {
478     default:
479         /* Shouldn't happen */
480         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
481         return WRITE_TRAN_ERROR;
482 
483     case TLS_ST_OK:
484         if (s->key_update != SSL_KEY_UPDATE_NONE) {
485             st->hand_state = TLS_ST_SW_KEY_UPDATE;
486             return WRITE_TRAN_CONTINUE;
487         }
488         if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
489             st->hand_state = TLS_ST_SW_CERT_REQ;
490             return WRITE_TRAN_CONTINUE;
491         }
492         if (s->ext.extra_tickets_expected > 0) {
493             st->hand_state = TLS_ST_SW_SESSION_TICKET;
494             return WRITE_TRAN_CONTINUE;
495         }
496         /* Try to read from the client instead */
497         return WRITE_TRAN_FINISHED;
498 
499     case TLS_ST_SR_CLNT_HELLO:
500         st->hand_state = TLS_ST_SW_SRVR_HELLO;
501         return WRITE_TRAN_CONTINUE;
502 
503     case TLS_ST_SW_SRVR_HELLO:
504         if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
505             && s->hello_retry_request != SSL_HRR_COMPLETE)
506             st->hand_state = TLS_ST_SW_CHANGE;
507         else if (s->hello_retry_request == SSL_HRR_PENDING)
508             st->hand_state = TLS_ST_EARLY_DATA;
509         else
510             st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS;
511         return WRITE_TRAN_CONTINUE;
512 
513     case TLS_ST_SW_CHANGE:
514         if (s->hello_retry_request == SSL_HRR_PENDING)
515             st->hand_state = TLS_ST_EARLY_DATA;
516         else
517             st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS;
518         return WRITE_TRAN_CONTINUE;
519 
520     case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
521         if (s->hit)
522             st->hand_state = TLS_ST_SW_FINISHED;
523         else if (send_certificate_request(s))
524             st->hand_state = TLS_ST_SW_CERT_REQ;
525         else if (do_compressed_cert(s))
526             st->hand_state = TLS_ST_SW_COMP_CERT;
527         else
528             st->hand_state = TLS_ST_SW_CERT;
529 
530         return WRITE_TRAN_CONTINUE;
531 
532     case TLS_ST_SW_CERT_REQ:
533         if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
534             s->post_handshake_auth = SSL_PHA_REQUESTED;
535             st->hand_state = TLS_ST_OK;
536         } else if (do_compressed_cert(s)) {
537             st->hand_state = TLS_ST_SW_COMP_CERT;
538         } else {
539             st->hand_state = TLS_ST_SW_CERT;
540         }
541         return WRITE_TRAN_CONTINUE;
542 
543     case TLS_ST_SW_COMP_CERT:
544     case TLS_ST_SW_CERT:
545         st->hand_state = TLS_ST_SW_CERT_VRFY;
546         return WRITE_TRAN_CONTINUE;
547 
548     case TLS_ST_SW_CERT_VRFY:
549         st->hand_state = TLS_ST_SW_FINISHED;
550         return WRITE_TRAN_CONTINUE;
551 
552     case TLS_ST_SW_FINISHED:
553         st->hand_state = TLS_ST_EARLY_DATA;
554         s->ts_msg_write = ossl_time_now();
555         return WRITE_TRAN_CONTINUE;
556 
557     case TLS_ST_EARLY_DATA:
558         return WRITE_TRAN_FINISHED;
559 
560     case TLS_ST_SR_FINISHED:
561         s->ts_msg_read = ossl_time_now();
562         /*
563          * Technically we have finished the handshake at this point, but we're
564          * going to remain "in_init" for now and write out any session tickets
565          * immediately.
566          */
567         if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
568             s->post_handshake_auth = SSL_PHA_EXT_RECEIVED;
569         } else if (!s->ext.ticket_expected) {
570             /*
571              * If we're not going to renew the ticket then we just finish the
572              * handshake at this point.
573              */
574             st->hand_state = TLS_ST_OK;
575             return WRITE_TRAN_CONTINUE;
576         }
577         if (s->num_tickets > s->sent_tickets)
578             st->hand_state = TLS_ST_SW_SESSION_TICKET;
579         else
580             st->hand_state = TLS_ST_OK;
581         return WRITE_TRAN_CONTINUE;
582 
583     case TLS_ST_SR_KEY_UPDATE:
584     case TLS_ST_SW_KEY_UPDATE:
585         st->hand_state = TLS_ST_OK;
586         return WRITE_TRAN_CONTINUE;
587 
588     case TLS_ST_SW_SESSION_TICKET:
589         /* In a resumption we only ever send a maximum of one new ticket.
590          * Following an initial handshake we send the number of tickets we have
591          * been configured for.
592          */
593         if (!SSL_IS_FIRST_HANDSHAKE(s) && s->ext.extra_tickets_expected > 0) {
594             return WRITE_TRAN_CONTINUE;
595         } else if (s->hit || s->num_tickets <= s->sent_tickets) {
596             /* We've written enough tickets out. */
597             st->hand_state = TLS_ST_OK;
598         }
599         return WRITE_TRAN_CONTINUE;
600     }
601 }
602 
603 /*
604  * ossl_statem_server_write_transition() works out what handshake state to move
605  * to next when the server is writing messages to be sent to the client.
606  */
ossl_statem_server_write_transition(SSL_CONNECTION * s)607 WRITE_TRAN ossl_statem_server_write_transition(SSL_CONNECTION *s)
608 {
609     OSSL_STATEM *st = &s->statem;
610 
611     /*
612      * Note that before the ClientHello we don't know what version we are going
613      * to negotiate yet, so we don't take this branch until later
614      */
615 
616     if (SSL_CONNECTION_IS_TLS13(s))
617         return ossl_statem_server13_write_transition(s);
618 
619     switch (st->hand_state) {
620     default:
621         /* Shouldn't happen */
622         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
623         return WRITE_TRAN_ERROR;
624 
625     case TLS_ST_OK:
626         if (st->request_state == TLS_ST_SW_HELLO_REQ) {
627             /* We must be trying to renegotiate */
628             st->hand_state = TLS_ST_SW_HELLO_REQ;
629             st->request_state = TLS_ST_BEFORE;
630             return WRITE_TRAN_CONTINUE;
631         }
632         /* Must be an incoming ClientHello */
633         if (!tls_setup_handshake(s)) {
634             /* SSLfatal() already called */
635             return WRITE_TRAN_ERROR;
636         }
637         /* Fall through */
638 
639     case TLS_ST_BEFORE:
640         /* Just go straight to trying to read from the client */
641         return WRITE_TRAN_FINISHED;
642 
643     case TLS_ST_SW_HELLO_REQ:
644         st->hand_state = TLS_ST_OK;
645         return WRITE_TRAN_CONTINUE;
646 
647     case TLS_ST_SR_CLNT_HELLO:
648         if (SSL_CONNECTION_IS_DTLS(s) && !s->d1->cookie_verified
649             && (SSL_get_options(SSL_CONNECTION_GET_SSL(s)) & SSL_OP_COOKIE_EXCHANGE)) {
650             st->hand_state = DTLS_ST_SW_HELLO_VERIFY_REQUEST;
651         } else if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) {
652             /* We must have rejected the renegotiation */
653             st->hand_state = TLS_ST_OK;
654             return WRITE_TRAN_CONTINUE;
655         } else {
656             st->hand_state = TLS_ST_SW_SRVR_HELLO;
657         }
658         return WRITE_TRAN_CONTINUE;
659 
660     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
661         return WRITE_TRAN_FINISHED;
662 
663     case TLS_ST_SW_SRVR_HELLO:
664         if (s->hit) {
665             if (s->ext.ticket_expected)
666                 st->hand_state = TLS_ST_SW_SESSION_TICKET;
667             else
668                 st->hand_state = TLS_ST_SW_CHANGE;
669         } else {
670             /* Check if it is anon DH or anon ECDH, */
671             /* normal PSK or SRP */
672             if (!(s->s3.tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP | SSL_aPSK))) {
673                 st->hand_state = TLS_ST_SW_CERT;
674             } else if (send_server_key_exchange(s)) {
675                 st->hand_state = TLS_ST_SW_KEY_EXCH;
676             } else if (send_certificate_request(s)) {
677                 st->hand_state = TLS_ST_SW_CERT_REQ;
678             } else {
679                 st->hand_state = TLS_ST_SW_SRVR_DONE;
680             }
681         }
682         return WRITE_TRAN_CONTINUE;
683 
684     case TLS_ST_SW_CERT:
685         if (s->ext.status_expected) {
686             st->hand_state = TLS_ST_SW_CERT_STATUS;
687             return WRITE_TRAN_CONTINUE;
688         }
689         /* Fall through */
690 
691     case TLS_ST_SW_CERT_STATUS:
692         if (send_server_key_exchange(s)) {
693             st->hand_state = TLS_ST_SW_KEY_EXCH;
694             return WRITE_TRAN_CONTINUE;
695         }
696         /* Fall through */
697 
698     case TLS_ST_SW_KEY_EXCH:
699         if (send_certificate_request(s)) {
700             st->hand_state = TLS_ST_SW_CERT_REQ;
701             return WRITE_TRAN_CONTINUE;
702         }
703         /* Fall through */
704 
705     case TLS_ST_SW_CERT_REQ:
706         st->hand_state = TLS_ST_SW_SRVR_DONE;
707         return WRITE_TRAN_CONTINUE;
708 
709     case TLS_ST_SW_SRVR_DONE:
710         s->ts_msg_write = ossl_time_now();
711         return WRITE_TRAN_FINISHED;
712 
713     case TLS_ST_SR_FINISHED:
714         s->ts_msg_read = ossl_time_now();
715         if (s->hit) {
716             st->hand_state = TLS_ST_OK;
717             return WRITE_TRAN_CONTINUE;
718         } else if (s->ext.ticket_expected) {
719             st->hand_state = TLS_ST_SW_SESSION_TICKET;
720         } else {
721             st->hand_state = TLS_ST_SW_CHANGE;
722         }
723         return WRITE_TRAN_CONTINUE;
724 
725     case TLS_ST_SW_SESSION_TICKET:
726         st->hand_state = TLS_ST_SW_CHANGE;
727         return WRITE_TRAN_CONTINUE;
728 
729     case TLS_ST_SW_CHANGE:
730         st->hand_state = TLS_ST_SW_FINISHED;
731         return WRITE_TRAN_CONTINUE;
732 
733     case TLS_ST_SW_FINISHED:
734         if (s->hit) {
735             return WRITE_TRAN_FINISHED;
736         }
737         st->hand_state = TLS_ST_OK;
738         return WRITE_TRAN_CONTINUE;
739     }
740 }
741 
742 /*
743  * Perform any pre work that needs to be done prior to sending a message from
744  * the server to the client.
745  */
ossl_statem_server_pre_work(SSL_CONNECTION * s,WORK_STATE wst)746 WORK_STATE ossl_statem_server_pre_work(SSL_CONNECTION *s, WORK_STATE wst)
747 {
748     OSSL_STATEM *st = &s->statem;
749     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
750 
751     switch (st->hand_state) {
752     default:
753         /* No pre work to be done */
754         break;
755 
756     case TLS_ST_SW_HELLO_REQ:
757         s->shutdown = 0;
758         if (SSL_CONNECTION_IS_DTLS(s))
759             dtls1_clear_sent_buffer(s);
760         break;
761 
762     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
763         s->shutdown = 0;
764         if (SSL_CONNECTION_IS_DTLS(s)) {
765             dtls1_clear_sent_buffer(s);
766             /* We don't buffer this message so don't use the timer */
767             st->use_timer = 0;
768         }
769         break;
770 
771     case TLS_ST_SW_SRVR_HELLO:
772         if (SSL_CONNECTION_IS_DTLS(s)) {
773             /*
774              * Messages we write from now on should be buffered and
775              * retransmitted if necessary, so we need to use the timer now
776              */
777             st->use_timer = 1;
778         }
779         break;
780 
781     case TLS_ST_SW_SRVR_DONE:
782 #ifndef OPENSSL_NO_SCTP
783         if (SSL_CONNECTION_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(ssl))) {
784             /* Calls SSLfatal() as required */
785             return dtls_wait_for_dry(s);
786         }
787 #endif
788         return WORK_FINISHED_CONTINUE;
789 
790     case TLS_ST_SW_SESSION_TICKET:
791         if (SSL_CONNECTION_IS_TLS13(s) && s->sent_tickets == 0
792             && s->ext.extra_tickets_expected == 0) {
793             /*
794              * Actually this is the end of the handshake, but we're going
795              * straight into writing the session ticket out. So we finish off
796              * the handshake, but keep the various buffers active.
797              *
798              * Calls SSLfatal as required.
799              */
800             return tls_finish_handshake(s, wst, 0, 0);
801         }
802         if (SSL_CONNECTION_IS_DTLS(s)) {
803             /*
804              * We're into the last flight. We don't retransmit the last flight
805              * unless we need to, so we don't use the timer
806              */
807             st->use_timer = 0;
808         }
809         break;
810 
811     case TLS_ST_SW_CHANGE:
812         if (SSL_CONNECTION_IS_TLS13(s))
813             break;
814         /* Writes to s->session are only safe for initial handshakes */
815         if (s->session->cipher == NULL) {
816             s->session->cipher = s->s3.tmp.new_cipher;
817         } else if (s->session->cipher != s->s3.tmp.new_cipher) {
818             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
819             return WORK_ERROR;
820         }
821         if (!ssl->method->ssl3_enc->setup_key_block(s)) {
822             /* SSLfatal() already called */
823             return WORK_ERROR;
824         }
825         if (SSL_CONNECTION_IS_DTLS(s)) {
826             /*
827              * We're into the last flight. We don't retransmit the last flight
828              * unless we need to, so we don't use the timer. This might have
829              * already been set to 0 if we sent a NewSessionTicket message,
830              * but we'll set it again here in case we didn't.
831              */
832             st->use_timer = 0;
833         }
834         return WORK_FINISHED_CONTINUE;
835 
836     case TLS_ST_EARLY_DATA:
837         if (s->early_data_state != SSL_EARLY_DATA_ACCEPTING
838             && (s->s3.flags & TLS1_FLAGS_STATELESS) == 0)
839             return WORK_FINISHED_CONTINUE;
840 
841         /*
842          * In QUIC with 0-RTT we just carry on when otherwise we would stop
843          * to allow the server to read early data
844          */
845         if (SSL_NO_EOED(s) && s->ext.early_data == SSL_EARLY_DATA_ACCEPTED
846             && s->early_data_state != SSL_EARLY_DATA_FINISHED_READING) {
847             s->early_data_state = SSL_EARLY_DATA_FINISHED_READING;
848             if (!ssl->method->ssl3_enc->change_cipher_state(s, SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_READ)) {
849                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
850                 return WORK_ERROR;
851             }
852             return WORK_FINISHED_SWAP;
853         }
854         /* Fall through */
855 
856     case TLS_ST_OK:
857         /* Calls SSLfatal() as required */
858         return tls_finish_handshake(s, wst, 1, 1);
859     }
860 
861     return WORK_FINISHED_CONTINUE;
862 }
863 
conn_is_closed(void)864 static ossl_inline int conn_is_closed(void)
865 {
866     switch (get_last_sys_error()) {
867 #if defined(EPIPE)
868     case EPIPE:
869         return 1;
870 #endif
871 #if defined(ECONNRESET)
872     case ECONNRESET:
873         return 1;
874 #endif
875 #if defined(WSAECONNRESET)
876     case WSAECONNRESET:
877         return 1;
878 #endif
879     default:
880         return 0;
881     }
882 }
883 
884 /*
885  * Perform any work that needs to be done after sending a message from the
886  * server to the client.
887  */
ossl_statem_server_post_work(SSL_CONNECTION * s,WORK_STATE wst)888 WORK_STATE ossl_statem_server_post_work(SSL_CONNECTION *s, WORK_STATE wst)
889 {
890     OSSL_STATEM *st = &s->statem;
891     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
892 
893     s->init_num = 0;
894 
895     switch (st->hand_state) {
896     default:
897         /* No post work to be done */
898         break;
899 
900     case TLS_ST_SW_HELLO_REQ:
901         if (statem_flush(s) != 1)
902             return WORK_MORE_A;
903         if (!ssl3_init_finished_mac(s)) {
904             /* SSLfatal() already called */
905             return WORK_ERROR;
906         }
907         break;
908 
909     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
910         if (statem_flush(s) != 1)
911             return WORK_MORE_A;
912         /* HelloVerifyRequest resets Finished MAC */
913         if (s->version != DTLS1_BAD_VER && !ssl3_init_finished_mac(s)) {
914             /* SSLfatal() already called */
915             return WORK_ERROR;
916         }
917         /*
918          * The next message should be another ClientHello which we need to
919          * treat like it was the first packet
920          */
921         s->first_packet = 1;
922         break;
923 
924     case TLS_ST_SW_SRVR_HELLO:
925         if (SSL_CONNECTION_IS_TLS13(s)
926             && s->hello_retry_request == SSL_HRR_PENDING) {
927             if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) == 0
928                 && statem_flush(s) != 1)
929                 return WORK_MORE_A;
930             break;
931         }
932 #ifndef OPENSSL_NO_SCTP
933         if (SSL_CONNECTION_IS_DTLS(s) && s->hit) {
934             unsigned char sctpauthkey[64];
935             char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
936             size_t labellen;
937 
938             /*
939              * Add new shared key for SCTP-Auth, will be ignored if no
940              * SCTP used.
941              */
942             memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
943                 sizeof(DTLS1_SCTP_AUTH_LABEL));
944 
945             /* Don't include the terminating zero. */
946             labellen = sizeof(labelbuffer) - 1;
947             if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
948                 labellen += 1;
949 
950             if (SSL_export_keying_material(ssl, sctpauthkey,
951                     sizeof(sctpauthkey), labelbuffer,
952                     labellen, NULL, 0,
953                     0)
954                 <= 0) {
955                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
956                 return WORK_ERROR;
957             }
958 
959             BIO_ctrl(SSL_get_wbio(ssl), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
960                 sizeof(sctpauthkey), sctpauthkey);
961         }
962 #endif
963         if (!SSL_CONNECTION_IS_TLS13(s)
964             || ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
965                 && s->hello_retry_request != SSL_HRR_COMPLETE))
966             break;
967         /* Fall through */
968 
969     case TLS_ST_SW_CHANGE:
970         if (s->hello_retry_request == SSL_HRR_PENDING) {
971             if (!statem_flush(s))
972                 return WORK_MORE_A;
973             break;
974         }
975 
976         if (SSL_CONNECTION_IS_TLS13(s)) {
977             if (!ssl->method->ssl3_enc->setup_key_block(s)
978                 || !tls13_store_handshake_traffic_hash(s)
979                 || !ssl->method->ssl3_enc->change_cipher_state(s,
980                     SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_WRITE)) {
981                 /* SSLfatal() already called */
982                 return WORK_ERROR;
983             }
984 
985             if (s->ext.early_data != SSL_EARLY_DATA_ACCEPTED
986                 && !ssl->method->ssl3_enc->change_cipher_state(s,
987                     SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_READ)) {
988                 /* SSLfatal() already called */
989                 return WORK_ERROR;
990             }
991             /*
992              * We don't yet know whether the next record we are going to receive
993              * is an unencrypted alert, an encrypted alert, or an encrypted
994              * handshake message. We temporarily tolerate unencrypted alerts.
995              */
996             if (s->rlayer.rrlmethod->set_plain_alerts != NULL)
997                 s->rlayer.rrlmethod->set_plain_alerts(s->rlayer.rrl, 1);
998             break;
999         }
1000 
1001 #ifndef OPENSSL_NO_SCTP
1002         if (SSL_CONNECTION_IS_DTLS(s) && !s->hit) {
1003             /*
1004              * Change to new shared key of SCTP-Auth, will be ignored if
1005              * no SCTP used.
1006              */
1007             BIO_ctrl(SSL_get_wbio(ssl), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
1008                 0, NULL);
1009         }
1010 #endif
1011         if (!ssl->method->ssl3_enc->change_cipher_state(s,
1012                 SSL3_CHANGE_CIPHER_SERVER_WRITE)) {
1013             /* SSLfatal() already called */
1014             return WORK_ERROR;
1015         }
1016         break;
1017 
1018     case TLS_ST_SW_SRVR_DONE:
1019         if (statem_flush(s) != 1)
1020             return WORK_MORE_A;
1021         break;
1022 
1023     case TLS_ST_SW_FINISHED:
1024         if (statem_flush(s) != 1)
1025             return WORK_MORE_A;
1026 #ifndef OPENSSL_NO_SCTP
1027         if (SSL_CONNECTION_IS_DTLS(s) && s->hit) {
1028             /*
1029              * Change to new shared key of SCTP-Auth, will be ignored if
1030              * no SCTP used.
1031              */
1032             BIO_ctrl(SSL_get_wbio(ssl), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
1033                 0, NULL);
1034         }
1035 #endif
1036         if (SSL_CONNECTION_IS_TLS13(s)) {
1037             /* TLS 1.3 gets the secret size from the handshake md */
1038             size_t dummy;
1039             if (!ssl->method->ssl3_enc->generate_master_secret(s,
1040                     s->master_secret, s->handshake_secret, 0,
1041                     &dummy)
1042                 || !tls13_store_server_finished_hash(s)
1043                 || !ssl->method->ssl3_enc->change_cipher_state(s,
1044                     SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_SERVER_WRITE))
1045                 /* SSLfatal() already called */
1046                 return WORK_ERROR;
1047         }
1048         break;
1049 
1050     case TLS_ST_SW_CERT_REQ:
1051         if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
1052             if (statem_flush(s) != 1)
1053                 return WORK_MORE_A;
1054         } else {
1055             if (!SSL_CONNECTION_IS_TLS13(s)
1056                 || (s->options & SSL_OP_NO_TX_CERTIFICATE_COMPRESSION) != 0)
1057                 s->ext.compress_certificate_from_peer[0] = TLSEXT_comp_cert_none;
1058         }
1059         break;
1060 
1061     case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
1062         if (!s->hit && !send_certificate_request(s)) {
1063             if (!SSL_CONNECTION_IS_TLS13(s)
1064                 || (s->options & SSL_OP_NO_TX_CERTIFICATE_COMPRESSION) != 0)
1065                 s->ext.compress_certificate_from_peer[0] = TLSEXT_comp_cert_none;
1066         }
1067         break;
1068 
1069     case TLS_ST_SW_KEY_UPDATE:
1070         if (statem_flush(s) != 1)
1071             return WORK_MORE_A;
1072         if (!tls13_update_key(s, 1)) {
1073             /* SSLfatal() already called */
1074             return WORK_ERROR;
1075         }
1076         break;
1077 
1078     case TLS_ST_SW_SESSION_TICKET:
1079         clear_sys_error();
1080         if (SSL_CONNECTION_IS_TLS13(s) && statem_flush(s) != 1) {
1081             if (SSL_get_error(ssl, 0) == SSL_ERROR_SYSCALL
1082                 && conn_is_closed()) {
1083                 /*
1084                  * We ignore connection closed errors in TLSv1.3 when sending a
1085                  * NewSessionTicket and behave as if we were successful. This is
1086                  * so that we are still able to read data sent to us by a client
1087                  * that closes soon after the end of the handshake without
1088                  * waiting to read our post-handshake NewSessionTickets.
1089                  */
1090                 s->rwstate = SSL_NOTHING;
1091                 break;
1092             }
1093 
1094             return WORK_MORE_A;
1095         }
1096         break;
1097     }
1098 
1099     return WORK_FINISHED_CONTINUE;
1100 }
1101 
1102 /*
1103  * Get the message construction function and message type for sending from the
1104  * server
1105  *
1106  * Valid return values are:
1107  *   1: Success
1108  *   0: Error
1109  */
ossl_statem_server_construct_message(SSL_CONNECTION * s,confunc_f * confunc,int * mt)1110 int ossl_statem_server_construct_message(SSL_CONNECTION *s,
1111     confunc_f *confunc, int *mt)
1112 {
1113     OSSL_STATEM *st = &s->statem;
1114 
1115     switch (st->hand_state) {
1116     default:
1117         /* Shouldn't happen */
1118         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_STATE);
1119         return 0;
1120 
1121     case TLS_ST_SW_CHANGE:
1122         if (SSL_CONNECTION_IS_DTLS(s))
1123             *confunc = dtls_construct_change_cipher_spec;
1124         else
1125             *confunc = tls_construct_change_cipher_spec;
1126         *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
1127         break;
1128 
1129     case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
1130         *confunc = dtls_construct_hello_verify_request;
1131         *mt = DTLS1_MT_HELLO_VERIFY_REQUEST;
1132         break;
1133 
1134     case TLS_ST_SW_HELLO_REQ:
1135         /* No construction function needed */
1136         *confunc = NULL;
1137         *mt = SSL3_MT_HELLO_REQUEST;
1138         break;
1139 
1140     case TLS_ST_SW_SRVR_HELLO:
1141         *confunc = tls_construct_server_hello;
1142         *mt = SSL3_MT_SERVER_HELLO;
1143         break;
1144 
1145     case TLS_ST_SW_CERT:
1146         *confunc = tls_construct_server_certificate;
1147         *mt = SSL3_MT_CERTIFICATE;
1148         break;
1149 
1150 #ifndef OPENSSL_NO_COMP_ALG
1151     case TLS_ST_SW_COMP_CERT:
1152         *confunc = tls_construct_server_compressed_certificate;
1153         *mt = SSL3_MT_COMPRESSED_CERTIFICATE;
1154         break;
1155 #endif
1156 
1157     case TLS_ST_SW_CERT_VRFY:
1158         *confunc = tls_construct_cert_verify;
1159         *mt = SSL3_MT_CERTIFICATE_VERIFY;
1160         break;
1161 
1162     case TLS_ST_SW_KEY_EXCH:
1163         *confunc = tls_construct_server_key_exchange;
1164         *mt = SSL3_MT_SERVER_KEY_EXCHANGE;
1165         break;
1166 
1167     case TLS_ST_SW_CERT_REQ:
1168         *confunc = tls_construct_certificate_request;
1169         *mt = SSL3_MT_CERTIFICATE_REQUEST;
1170         break;
1171 
1172     case TLS_ST_SW_SRVR_DONE:
1173         *confunc = tls_construct_server_done;
1174         *mt = SSL3_MT_SERVER_DONE;
1175         break;
1176 
1177     case TLS_ST_SW_SESSION_TICKET:
1178         *confunc = tls_construct_new_session_ticket;
1179         *mt = SSL3_MT_NEWSESSION_TICKET;
1180         break;
1181 
1182     case TLS_ST_SW_CERT_STATUS:
1183         *confunc = tls_construct_cert_status;
1184         *mt = SSL3_MT_CERTIFICATE_STATUS;
1185         break;
1186 
1187     case TLS_ST_SW_FINISHED:
1188         *confunc = tls_construct_finished;
1189         *mt = SSL3_MT_FINISHED;
1190         break;
1191 
1192     case TLS_ST_EARLY_DATA:
1193         *confunc = NULL;
1194         *mt = SSL3_MT_DUMMY;
1195         break;
1196 
1197     case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
1198         *confunc = tls_construct_encrypted_extensions;
1199         *mt = SSL3_MT_ENCRYPTED_EXTENSIONS;
1200         break;
1201 
1202     case TLS_ST_SW_KEY_UPDATE:
1203         *confunc = tls_construct_key_update;
1204         *mt = SSL3_MT_KEY_UPDATE;
1205         break;
1206     }
1207 
1208     return 1;
1209 }
1210 
1211 /*
1212  * Maximum size (excluding the Handshake header) of a ClientHello message,
1213  * calculated as follows:
1214  *
1215  *  2 + # client_version
1216  *  32 + # only valid length for random
1217  *  1 + # length of session_id
1218  *  32 + # maximum size for session_id
1219  *  2 + # length of cipher suites
1220  *  2^16-2 + # maximum length of cipher suites array
1221  *  1 + # length of compression_methods
1222  *  2^8-1 + # maximum length of compression methods
1223  *  2 + # length of extensions
1224  *  2^16-1 # maximum length of extensions
1225  */
1226 #define CLIENT_HELLO_MAX_LENGTH 131396
1227 
1228 #define CLIENT_KEY_EXCH_MAX_LENGTH 2048
1229 #define NEXT_PROTO_MAX_LENGTH 514
1230 
1231 /*
1232  * Returns the maximum allowed length for the current message that we are
1233  * reading. Excludes the message header.
1234  */
ossl_statem_server_max_message_size(SSL_CONNECTION * s)1235 size_t ossl_statem_server_max_message_size(SSL_CONNECTION *s)
1236 {
1237     OSSL_STATEM *st = &s->statem;
1238 
1239     switch (st->hand_state) {
1240     default:
1241         /* Shouldn't happen */
1242         return 0;
1243 
1244     case TLS_ST_SR_CLNT_HELLO:
1245         return CLIENT_HELLO_MAX_LENGTH;
1246 
1247     case TLS_ST_SR_END_OF_EARLY_DATA:
1248         return END_OF_EARLY_DATA_MAX_LENGTH;
1249 
1250     case TLS_ST_SR_COMP_CERT:
1251     case TLS_ST_SR_CERT:
1252         return s->max_cert_list;
1253 
1254     case TLS_ST_SR_KEY_EXCH:
1255         return CLIENT_KEY_EXCH_MAX_LENGTH;
1256 
1257     case TLS_ST_SR_CERT_VRFY:
1258         return CERTIFICATE_VERIFY_MAX_LENGTH;
1259 
1260 #ifndef OPENSSL_NO_NEXTPROTONEG
1261     case TLS_ST_SR_NEXT_PROTO:
1262         return NEXT_PROTO_MAX_LENGTH;
1263 #endif
1264 
1265     case TLS_ST_SR_CHANGE:
1266         return CCS_MAX_LENGTH;
1267 
1268     case TLS_ST_SR_FINISHED:
1269         return FINISHED_MAX_LENGTH;
1270 
1271     case TLS_ST_SR_KEY_UPDATE:
1272         return KEY_UPDATE_MAX_LENGTH;
1273     }
1274 }
1275 
1276 /*
1277  * Process a message that the server has received from the client.
1278  */
ossl_statem_server_process_message(SSL_CONNECTION * s,PACKET * pkt)1279 MSG_PROCESS_RETURN ossl_statem_server_process_message(SSL_CONNECTION *s,
1280     PACKET *pkt)
1281 {
1282     OSSL_STATEM *st = &s->statem;
1283 
1284     switch (st->hand_state) {
1285     default:
1286         /* Shouldn't happen */
1287         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1288         return MSG_PROCESS_ERROR;
1289 
1290     case TLS_ST_SR_CLNT_HELLO:
1291         return tls_process_client_hello(s, pkt);
1292 
1293     case TLS_ST_SR_END_OF_EARLY_DATA:
1294         return tls_process_end_of_early_data(s, pkt);
1295 
1296     case TLS_ST_SR_CERT:
1297         return tls_process_client_certificate(s, pkt);
1298 
1299 #ifndef OPENSSL_NO_COMP_ALG
1300     case TLS_ST_SR_COMP_CERT:
1301         return tls_process_client_compressed_certificate(s, pkt);
1302 #endif
1303 
1304     case TLS_ST_SR_KEY_EXCH:
1305         return tls_process_client_key_exchange(s, pkt);
1306 
1307     case TLS_ST_SR_CERT_VRFY:
1308         return tls_process_cert_verify(s, pkt);
1309 
1310 #ifndef OPENSSL_NO_NEXTPROTONEG
1311     case TLS_ST_SR_NEXT_PROTO:
1312         return tls_process_next_proto(s, pkt);
1313 #endif
1314 
1315     case TLS_ST_SR_CHANGE:
1316         return tls_process_change_cipher_spec(s, pkt);
1317 
1318     case TLS_ST_SR_FINISHED:
1319         return tls_process_finished(s, pkt);
1320 
1321     case TLS_ST_SR_KEY_UPDATE:
1322         return tls_process_key_update(s, pkt);
1323     }
1324 }
1325 
1326 /*
1327  * Perform any further processing required following the receipt of a message
1328  * from the client
1329  */
ossl_statem_server_post_process_message(SSL_CONNECTION * s,WORK_STATE wst)1330 WORK_STATE ossl_statem_server_post_process_message(SSL_CONNECTION *s,
1331     WORK_STATE wst)
1332 {
1333     OSSL_STATEM *st = &s->statem;
1334 
1335     switch (st->hand_state) {
1336     default:
1337         /* Shouldn't happen */
1338         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1339         return WORK_ERROR;
1340 
1341     case TLS_ST_SR_CLNT_HELLO:
1342         return tls_post_process_client_hello(s, wst);
1343 
1344     case TLS_ST_SR_KEY_EXCH:
1345         return tls_post_process_client_key_exchange(s, wst);
1346     }
1347 }
1348 
1349 #ifndef OPENSSL_NO_SRP
1350 /* Returns 1 on success, 0 for retryable error, -1 for fatal error */
ssl_check_srp_ext_ClientHello(SSL_CONNECTION * s)1351 static int ssl_check_srp_ext_ClientHello(SSL_CONNECTION *s)
1352 {
1353     int ret;
1354     int al = SSL_AD_UNRECOGNIZED_NAME;
1355 
1356     if ((s->s3.tmp.new_cipher->algorithm_mkey & SSL_kSRP) && (s->srp_ctx.TLS_ext_srp_username_callback != NULL)) {
1357         if (s->srp_ctx.login == NULL) {
1358             /*
1359              * RFC 5054 says SHOULD reject, we do so if There is no srp
1360              * login name
1361              */
1362             SSLfatal(s, SSL_AD_UNKNOWN_PSK_IDENTITY,
1363                 SSL_R_PSK_IDENTITY_NOT_FOUND);
1364             return -1;
1365         } else {
1366             ret = ssl_srp_server_param_with_username_intern(s, &al);
1367             if (ret < 0)
1368                 return 0;
1369             if (ret == SSL3_AL_FATAL) {
1370                 SSLfatal(s, al,
1371                     al == SSL_AD_UNKNOWN_PSK_IDENTITY
1372                         ? SSL_R_PSK_IDENTITY_NOT_FOUND
1373                         : SSL_R_CLIENTHELLO_TLSEXT);
1374                 return -1;
1375             }
1376         }
1377     }
1378     return 1;
1379 }
1380 #endif
1381 
dtls_raw_hello_verify_request(WPACKET * pkt,unsigned char * cookie,size_t cookie_len)1382 int dtls_raw_hello_verify_request(WPACKET *pkt, unsigned char *cookie,
1383     size_t cookie_len)
1384 {
1385     /* Always use DTLS 1.0 version: see RFC 6347 */
1386     if (!WPACKET_put_bytes_u16(pkt, DTLS1_VERSION)
1387         || !WPACKET_sub_memcpy_u8(pkt, cookie, cookie_len))
1388         return 0;
1389 
1390     return 1;
1391 }
1392 
dtls_construct_hello_verify_request(SSL_CONNECTION * s,WPACKET * pkt)1393 CON_FUNC_RETURN dtls_construct_hello_verify_request(SSL_CONNECTION *s,
1394     WPACKET *pkt)
1395 {
1396     unsigned int cookie_leni;
1397     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
1398 
1399     if (sctx->app_gen_cookie_cb == NULL
1400         || sctx->app_gen_cookie_cb(SSL_CONNECTION_GET_USER_SSL(s), s->d1->cookie,
1401                &cookie_leni)
1402             == 0
1403         || cookie_leni > DTLS1_COOKIE_LENGTH) {
1404         SSLfatal(s, SSL_AD_NO_ALERT, SSL_R_COOKIE_GEN_CALLBACK_FAILURE);
1405         return CON_FUNC_ERROR;
1406     }
1407     s->d1->cookie_len = cookie_leni;
1408 
1409     if (!dtls_raw_hello_verify_request(pkt, s->d1->cookie,
1410             s->d1->cookie_len)) {
1411         SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
1412         return CON_FUNC_ERROR;
1413     }
1414 
1415     return CON_FUNC_SUCCESS;
1416 }
1417 
1418 /*-
1419  * ssl_check_for_safari attempts to fingerprint Safari using OS X
1420  * SecureTransport using the TLS extension block in |hello|.
1421  * Safari, since 10.6, sends exactly these extensions, in this order:
1422  *   SNI,
1423  *   elliptic_curves
1424  *   ec_point_formats
1425  *   signature_algorithms (for TLSv1.2 only)
1426  *
1427  * We wish to fingerprint Safari because they broke ECDHE-ECDSA support in 10.8,
1428  * but they advertise support. So enabling ECDHE-ECDSA ciphers breaks them.
1429  * Sadly we cannot differentiate 10.6, 10.7 and 10.8.4 (which work), from
1430  * 10.8..10.8.3 (which don't work).
1431  */
ssl_check_for_safari(SSL_CONNECTION * s,const CLIENTHELLO_MSG * hello)1432 static void ssl_check_for_safari(SSL_CONNECTION *s,
1433     const CLIENTHELLO_MSG *hello)
1434 {
1435     static const unsigned char kSafariExtensionsBlock[] = {
1436         0x00,
1437         0x0a, /* elliptic_curves extension */
1438         0x00,
1439         0x08, /* 8 bytes */
1440         0x00,
1441         0x06, /* 6 bytes of curve ids */
1442         0x00,
1443         0x17, /* P-256 */
1444         0x00,
1445         0x18, /* P-384 */
1446         0x00,
1447         0x19, /* P-521 */
1448 
1449         0x00,
1450         0x0b, /* ec_point_formats */
1451         0x00,
1452         0x02, /* 2 bytes */
1453         0x01, /* 1 point format */
1454         0x00, /* uncompressed */
1455         /* The following is only present in TLS 1.2 */
1456         0x00,
1457         0x0d, /* signature_algorithms */
1458         0x00,
1459         0x0c, /* 12 bytes */
1460         0x00,
1461         0x0a, /* 10 bytes */
1462         0x05,
1463         0x01, /* SHA-384/RSA */
1464         0x04,
1465         0x01, /* SHA-256/RSA */
1466         0x02,
1467         0x01, /* SHA-1/RSA */
1468         0x04,
1469         0x03, /* SHA-256/ECDSA */
1470         0x02,
1471         0x03, /* SHA-1/ECDSA */
1472     };
1473     /* Length of the common prefix (first two extensions). */
1474     static const size_t kSafariCommonExtensionsLength = 18;
1475     unsigned int type;
1476     PACKET sni, tmppkt;
1477     size_t ext_len;
1478 
1479     tmppkt = hello->extensions;
1480 
1481     if (!PACKET_forward(&tmppkt, 2)
1482         || !PACKET_get_net_2(&tmppkt, &type)
1483         || !PACKET_get_length_prefixed_2(&tmppkt, &sni)) {
1484         return;
1485     }
1486 
1487     if (type != TLSEXT_TYPE_server_name)
1488         return;
1489 
1490     ext_len = TLS1_get_client_version(
1491                   SSL_CONNECTION_GET_SSL(s))
1492             >= TLS1_2_VERSION
1493         ? sizeof(kSafariExtensionsBlock)
1494         : kSafariCommonExtensionsLength;
1495 
1496     s->s3.is_probably_safari = PACKET_equal(&tmppkt, kSafariExtensionsBlock,
1497         ext_len);
1498 }
1499 
1500 #define RENEG_OPTIONS_OK(options)             \
1501     ((options & SSL_OP_NO_RENEGOTIATION) == 0 \
1502         && (options & SSL_OP_ALLOW_CLIENT_RENEGOTIATION) != 0)
1503 
tls_process_client_hello(SSL_CONNECTION * s,PACKET * pkt)1504 MSG_PROCESS_RETURN tls_process_client_hello(SSL_CONNECTION *s, PACKET *pkt)
1505 {
1506     /* |cookie| will only be initialized for DTLS. */
1507     PACKET session_id, compression, extensions, cookie;
1508     static const unsigned char null_compression = 0;
1509     CLIENTHELLO_MSG *clienthello = NULL;
1510 
1511     /* Check if this is actually an unexpected renegotiation ClientHello */
1512     if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) {
1513         if (!ossl_assert(!SSL_CONNECTION_IS_TLS13(s))) {
1514             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1515             goto err;
1516         }
1517         if (!RENEG_OPTIONS_OK(s->options)
1518             || (!s->s3.send_connection_binding
1519                 && (s->options
1520                        & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
1521                     == 0)) {
1522             ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1523             return MSG_PROCESS_FINISHED_READING;
1524         }
1525         s->renegotiate = 1;
1526         s->new_session = 1;
1527     }
1528 
1529     clienthello = OPENSSL_zalloc(sizeof(*clienthello));
1530     if (clienthello == NULL) {
1531         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1532         goto err;
1533     }
1534 
1535     /*
1536      * First, parse the raw ClientHello data into the CLIENTHELLO_MSG structure.
1537      */
1538     clienthello->isv2 = RECORD_LAYER_is_sslv2_record(&s->rlayer);
1539     PACKET_null_init(&cookie);
1540 
1541     if (clienthello->isv2) {
1542         unsigned int mt;
1543 
1544         if (!SSL_IS_FIRST_HANDSHAKE(s)
1545             || s->hello_retry_request != SSL_HRR_NONE) {
1546             SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
1547             goto err;
1548         }
1549 
1550         /*-
1551          * An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
1552          * header is sent directly on the wire, not wrapped as a TLS
1553          * record. Our record layer just processes the message length and passes
1554          * the rest right through. Its format is:
1555          * Byte  Content
1556          * 0-1   msg_length - decoded by the record layer
1557          * 2     msg_type - s->init_msg points here
1558          * 3-4   version
1559          * 5-6   cipher_spec_length
1560          * 7-8   session_id_length
1561          * 9-10  challenge_length
1562          * ...   ...
1563          */
1564 
1565         if (!PACKET_get_1(pkt, &mt)
1566             || mt != SSL2_MT_CLIENT_HELLO) {
1567             /*
1568              * Should never happen. We should have tested this in the record
1569              * layer in order to have determined that this is an SSLv2 record
1570              * in the first place
1571              */
1572             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1573             goto err;
1574         }
1575     }
1576 
1577     if (!PACKET_get_net_2(pkt, &clienthello->legacy_version)) {
1578         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
1579         goto err;
1580     }
1581 
1582     /* Parse the message and load client random. */
1583     if (clienthello->isv2) {
1584         /*
1585          * Handle an SSLv2 backwards compatible ClientHello
1586          * Note, this is only for SSLv3+ using the backward compatible format.
1587          * Real SSLv2 is not supported, and is rejected below.
1588          */
1589         unsigned int ciphersuite_len, session_id_len, challenge_len;
1590         PACKET challenge;
1591 
1592         if (!PACKET_get_net_2(pkt, &ciphersuite_len)
1593             || !PACKET_get_net_2(pkt, &session_id_len)
1594             || !PACKET_get_net_2(pkt, &challenge_len)) {
1595             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RECORD_LENGTH_MISMATCH);
1596             goto err;
1597         }
1598 
1599         if (session_id_len > SSL_MAX_SSL_SESSION_ID_LENGTH) {
1600             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_LENGTH_MISMATCH);
1601             goto err;
1602         }
1603 
1604         if (!PACKET_get_sub_packet(pkt, &clienthello->ciphersuites,
1605                 ciphersuite_len)
1606             || !PACKET_copy_bytes(pkt, clienthello->session_id, session_id_len)
1607             || !PACKET_get_sub_packet(pkt, &challenge, challenge_len)
1608             /* No extensions. */
1609             || PACKET_remaining(pkt) != 0) {
1610             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RECORD_LENGTH_MISMATCH);
1611             goto err;
1612         }
1613         clienthello->session_id_len = session_id_len;
1614 
1615         /* Load the client random and compression list. We use SSL3_RANDOM_SIZE
1616          * here rather than sizeof(clienthello->random) because that is the limit
1617          * for SSLv3 and it is fixed. It won't change even if
1618          * sizeof(clienthello->random) does.
1619          */
1620         challenge_len = challenge_len > SSL3_RANDOM_SIZE
1621             ? SSL3_RANDOM_SIZE
1622             : challenge_len;
1623         memset(clienthello->random, 0, SSL3_RANDOM_SIZE);
1624         if (!PACKET_copy_bytes(&challenge,
1625                 clienthello->random + SSL3_RANDOM_SIZE - challenge_len, challenge_len)
1626             /* Advertise only null compression. */
1627             || !PACKET_buf_init(&compression, &null_compression, 1)) {
1628             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1629             goto err;
1630         }
1631 
1632         PACKET_null_init(&clienthello->extensions);
1633     } else {
1634         /* Regular ClientHello. */
1635         if (!PACKET_copy_bytes(pkt, clienthello->random, SSL3_RANDOM_SIZE)
1636             || !PACKET_get_length_prefixed_1(pkt, &session_id)
1637             || !PACKET_copy_all(&session_id, clienthello->session_id,
1638                 SSL_MAX_SSL_SESSION_ID_LENGTH,
1639                 &clienthello->session_id_len)) {
1640             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1641             goto err;
1642         }
1643 
1644         if (SSL_CONNECTION_IS_DTLS(s)) {
1645             if (!PACKET_get_length_prefixed_1(pkt, &cookie)) {
1646                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1647                 goto err;
1648             }
1649             if (!PACKET_copy_all(&cookie, clienthello->dtls_cookie,
1650                     DTLS1_COOKIE_LENGTH,
1651                     &clienthello->dtls_cookie_len)) {
1652                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1653                 goto err;
1654             }
1655             /*
1656              * If we require cookies and this ClientHello doesn't contain one,
1657              * just return since we do not want to allocate any memory yet.
1658              * So check cookie length...
1659              */
1660             if (SSL_get_options(SSL_CONNECTION_GET_SSL(s)) & SSL_OP_COOKIE_EXCHANGE) {
1661                 if (clienthello->dtls_cookie_len == 0) {
1662                     OPENSSL_free(clienthello);
1663                     return MSG_PROCESS_FINISHED_READING;
1664                 }
1665             }
1666         }
1667 
1668         if (!PACKET_get_length_prefixed_2(pkt, &clienthello->ciphersuites)) {
1669             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1670             goto err;
1671         }
1672 
1673         if (!PACKET_get_length_prefixed_1(pkt, &compression)) {
1674             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1675             goto err;
1676         }
1677 
1678         /* Could be empty. */
1679         if (PACKET_remaining(pkt) == 0) {
1680             PACKET_null_init(&clienthello->extensions);
1681         } else {
1682             if (!PACKET_get_length_prefixed_2(pkt, &clienthello->extensions)
1683                 || PACKET_remaining(pkt) != 0) {
1684                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1685                 goto err;
1686             }
1687         }
1688     }
1689 
1690     if (!PACKET_copy_all(&compression, clienthello->compressions,
1691             MAX_COMPRESSIONS_SIZE,
1692             &clienthello->compressions_len)) {
1693         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1694         goto err;
1695     }
1696 
1697     /* Preserve the raw extensions PACKET for later use */
1698     extensions = clienthello->extensions;
1699     if (!tls_collect_extensions(s, &extensions, SSL_EXT_CLIENT_HELLO,
1700             &clienthello->pre_proc_exts,
1701             &clienthello->pre_proc_exts_len, 1)) {
1702         /* SSLfatal already been called */
1703         goto err;
1704     }
1705     s->clienthello = clienthello;
1706 
1707     return MSG_PROCESS_CONTINUE_PROCESSING;
1708 
1709 err:
1710     if (clienthello != NULL)
1711         OPENSSL_free(clienthello->pre_proc_exts);
1712     OPENSSL_free(clienthello);
1713 
1714     return MSG_PROCESS_ERROR;
1715 }
1716 
tls_early_post_process_client_hello(SSL_CONNECTION * s)1717 static int tls_early_post_process_client_hello(SSL_CONNECTION *s)
1718 {
1719     unsigned int j;
1720     int i, al = SSL_AD_INTERNAL_ERROR;
1721     int protverr;
1722     unsigned long id;
1723 #ifndef OPENSSL_NO_COMP
1724     SSL_COMP *comp = NULL;
1725 #endif
1726     const SSL_CIPHER *c;
1727     STACK_OF(SSL_CIPHER) *ciphers = NULL;
1728     STACK_OF(SSL_CIPHER) *scsvs = NULL;
1729     CLIENTHELLO_MSG *clienthello = s->clienthello;
1730     DOWNGRADE dgrd = DOWNGRADE_NONE;
1731     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
1732     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
1733     SSL *ussl = SSL_CONNECTION_GET_USER_SSL(s);
1734 
1735     /* Finished parsing the ClientHello, now we can start processing it */
1736     /* Give the ClientHello callback a crack at things */
1737     if (sctx->client_hello_cb != NULL) {
1738         /* A failure in the ClientHello callback terminates the connection. */
1739         switch (sctx->client_hello_cb(ussl, &al, sctx->client_hello_cb_arg)) {
1740         case SSL_CLIENT_HELLO_SUCCESS:
1741             break;
1742         case SSL_CLIENT_HELLO_RETRY:
1743             s->rwstate = SSL_CLIENT_HELLO_CB;
1744             return -1;
1745         case SSL_CLIENT_HELLO_ERROR:
1746         default:
1747             SSLfatal(s, al, SSL_R_CALLBACK_FAILED);
1748             goto err;
1749         }
1750     }
1751 
1752     /* Set up the client_random */
1753     memcpy(s->s3.client_random, clienthello->random, SSL3_RANDOM_SIZE);
1754 
1755     /* Choose the version */
1756 
1757     if (clienthello->isv2) {
1758         if (clienthello->legacy_version == SSL2_VERSION
1759             || (clienthello->legacy_version & 0xff00)
1760                 != (SSL3_VERSION_MAJOR << 8)) {
1761             /*
1762              * This is real SSLv2 or something completely unknown. We don't
1763              * support it.
1764              */
1765             SSLfatal(s, SSL_AD_PROTOCOL_VERSION, SSL_R_UNKNOWN_PROTOCOL);
1766             goto err;
1767         }
1768         /* SSLv3/TLS */
1769         s->client_version = clienthello->legacy_version;
1770     }
1771 
1772     /* Choose the server SSL/TLS/DTLS version. */
1773     protverr = ssl_choose_server_version(s, clienthello, &dgrd);
1774 
1775     if (protverr) {
1776         if (SSL_IS_FIRST_HANDSHAKE(s)) {
1777             /* like ssl3_get_record, send alert using remote version number */
1778             s->version = s->client_version = clienthello->legacy_version;
1779         }
1780         SSLfatal(s, SSL_AD_PROTOCOL_VERSION, protverr);
1781         goto err;
1782     }
1783 
1784     /* TLSv1.3 specifies that a ClientHello must end on a record boundary */
1785     if (SSL_CONNECTION_IS_TLS13(s)
1786         && RECORD_LAYER_processed_read_pending(&s->rlayer)) {
1787         SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_NOT_ON_RECORD_BOUNDARY);
1788         goto err;
1789     }
1790 
1791     if (SSL_CONNECTION_IS_DTLS(s)) {
1792         /* Empty cookie was already handled above by returning early. */
1793         if (SSL_get_options(ssl) & SSL_OP_COOKIE_EXCHANGE) {
1794             if (sctx->app_verify_cookie_cb != NULL) {
1795                 if (sctx->app_verify_cookie_cb(ussl, clienthello->dtls_cookie,
1796                         clienthello->dtls_cookie_len)
1797                     == 0) {
1798                     SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1799                         SSL_R_COOKIE_MISMATCH);
1800                     goto err;
1801                     /* else cookie verification succeeded */
1802                 }
1803                 /* default verification */
1804             } else if (s->d1->cookie_len != clienthello->dtls_cookie_len
1805                 || memcmp(clienthello->dtls_cookie, s->d1->cookie,
1806                        s->d1->cookie_len)
1807                     != 0) {
1808                 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_COOKIE_MISMATCH);
1809                 goto err;
1810             }
1811             s->d1->cookie_verified = 1;
1812         }
1813     }
1814 
1815     s->hit = 0;
1816 
1817     if (!ssl_cache_cipherlist(s, &clienthello->ciphersuites,
1818             clienthello->isv2)
1819         || !ossl_bytes_to_cipher_list(s, &clienthello->ciphersuites, &ciphers,
1820             &scsvs, clienthello->isv2, 1)) {
1821         /* SSLfatal() already called */
1822         goto err;
1823     }
1824 
1825     s->s3.send_connection_binding = 0;
1826     /* Check what signalling cipher-suite values were received. */
1827     if (scsvs != NULL) {
1828         for (i = 0; i < sk_SSL_CIPHER_num(scsvs); i++) {
1829             c = sk_SSL_CIPHER_value(scsvs, i);
1830             if (SSL_CIPHER_get_id(c) == SSL3_CK_SCSV) {
1831                 if (s->renegotiate) {
1832                     /* SCSV is fatal if renegotiating */
1833                     SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1834                         SSL_R_SCSV_RECEIVED_WHEN_RENEGOTIATING);
1835                     goto err;
1836                 }
1837                 s->s3.send_connection_binding = 1;
1838             } else if (SSL_CIPHER_get_id(c) == SSL3_CK_FALLBACK_SCSV && !ssl_check_version_downgrade(s)) {
1839                 /*
1840                  * This SCSV indicates that the client previously tried
1841                  * a higher version.  We should fail if the current version
1842                  * is an unexpected downgrade, as that indicates that the first
1843                  * connection may have been tampered with in order to trigger
1844                  * an insecure downgrade.
1845                  */
1846                 SSLfatal(s, SSL_AD_INAPPROPRIATE_FALLBACK,
1847                     SSL_R_INAPPROPRIATE_FALLBACK);
1848                 goto err;
1849             }
1850         }
1851     }
1852 
1853     /* For TLSv1.3 we must select the ciphersuite *before* session resumption */
1854     if (SSL_CONNECTION_IS_TLS13(s)) {
1855         const SSL_CIPHER *cipher = ssl3_choose_cipher(s, ciphers, SSL_get_ciphers(ssl));
1856 
1857         if (cipher == NULL) {
1858             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_NO_SHARED_CIPHER);
1859             goto err;
1860         }
1861         if (s->hello_retry_request == SSL_HRR_PENDING
1862             && (s->s3.tmp.new_cipher == NULL
1863                 || s->s3.tmp.new_cipher->id != cipher->id)) {
1864             /*
1865              * A previous HRR picked a different ciphersuite to the one we
1866              * just selected. Something must have changed.
1867              */
1868             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_CIPHER);
1869             goto err;
1870         }
1871         s->s3.tmp.new_cipher = cipher;
1872     }
1873 
1874     /* We need to do this before getting the session */
1875     if (!tls_parse_extension(s, TLSEXT_IDX_extended_master_secret,
1876             SSL_EXT_CLIENT_HELLO,
1877             clienthello->pre_proc_exts, NULL, 0)) {
1878         /* SSLfatal() already called */
1879         goto err;
1880     }
1881 
1882     /*
1883      * We don't allow resumption in a backwards compatible ClientHello.
1884      * In TLS1.1+, session_id MUST be empty.
1885      *
1886      * Versions before 0.9.7 always allow clients to resume sessions in
1887      * renegotiation. 0.9.7 and later allow this by default, but optionally
1888      * ignore resumption requests with flag
1889      * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather
1890      * than a change to default behavior so that applications relying on
1891      * this for security won't even compile against older library versions).
1892      * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to
1893      * request renegotiation but not a new session (s->new_session remains
1894      * unset): for servers, this essentially just means that the
1895      * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be
1896      * ignored.
1897      */
1898     if (clienthello->isv2 || (s->new_session && (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) {
1899         if (!ssl_get_new_session(s, 1)) {
1900             /* SSLfatal() already called */
1901             goto err;
1902         }
1903     } else {
1904         i = ssl_get_prev_session(s, clienthello);
1905         if (i == 1) {
1906             /* previous session */
1907             s->hit = 1;
1908         } else if (i == -1) {
1909             /* SSLfatal() already called */
1910             goto err;
1911         } else {
1912             /* i == 0 */
1913             if (!ssl_get_new_session(s, 1)) {
1914                 /* SSLfatal() already called */
1915                 goto err;
1916             }
1917         }
1918     }
1919 
1920     if (SSL_CONNECTION_IS_TLS13(s)) {
1921         memcpy(s->tmp_session_id, s->clienthello->session_id,
1922             s->clienthello->session_id_len);
1923         s->tmp_session_id_len = s->clienthello->session_id_len;
1924     }
1925 
1926     /*
1927      * If it is a hit, check that the cipher is in the list. In TLSv1.3 we check
1928      * ciphersuite compatibility with the session as part of resumption.
1929      */
1930     if (!SSL_CONNECTION_IS_TLS13(s) && s->hit) {
1931         j = 0;
1932         id = s->session->cipher->id;
1933 
1934         OSSL_TRACE_BEGIN(TLS_CIPHER)
1935         {
1936             BIO_printf(trc_out, "client sent %d ciphers\n",
1937                 sk_SSL_CIPHER_num(ciphers));
1938         }
1939         for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) {
1940             c = sk_SSL_CIPHER_value(ciphers, i);
1941             if (trc_out != NULL)
1942                 BIO_printf(trc_out, "client [%2d of %2d]:%s\n", i,
1943                     sk_SSL_CIPHER_num(ciphers), SSL_CIPHER_get_name(c));
1944             if (c->id == id) {
1945                 j = 1;
1946                 break;
1947             }
1948         }
1949         if (j == 0) {
1950             /*
1951              * we need to have the cipher in the cipher list if we are asked
1952              * to reuse it
1953              */
1954             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1955                 SSL_R_REQUIRED_CIPHER_MISSING);
1956             OSSL_TRACE_CANCEL(TLS_CIPHER);
1957             goto err;
1958         }
1959         OSSL_TRACE_END(TLS_CIPHER);
1960     }
1961 
1962     /* At least one compression method must be preset. */
1963     if (clienthello->compressions_len == 0) {
1964         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_NO_COMPRESSION_SPECIFIED);
1965         goto err;
1966     }
1967     /* Make sure at least the null compression is supported. */
1968     if (memchr(clienthello->compressions, 0,
1969             clienthello->compressions_len)
1970         == NULL) {
1971         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1972             SSL_R_REQUIRED_COMPRESSION_ALGORITHM_MISSING);
1973         goto err;
1974     }
1975 
1976     if (s->options & SSL_OP_SAFARI_ECDHE_ECDSA_BUG)
1977         ssl_check_for_safari(s, clienthello);
1978 
1979     /* TLS extensions */
1980     if (!tls_parse_all_extensions(s, SSL_EXT_CLIENT_HELLO,
1981             clienthello->pre_proc_exts, NULL, 0, 1)) {
1982         /* SSLfatal() already called */
1983         goto err;
1984     }
1985 
1986     /*
1987      * Check if we want to use external pre-shared secret for this handshake
1988      * for not reused session only. We need to generate server_random before
1989      * calling tls_session_secret_cb in order to allow SessionTicket
1990      * processing to use it in key derivation.
1991      */
1992     {
1993         unsigned char *pos;
1994         pos = s->s3.server_random;
1995         if (ssl_fill_hello_random(s, 1, pos, SSL3_RANDOM_SIZE, dgrd) <= 0) {
1996             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1997             goto err;
1998         }
1999     }
2000 
2001     if (!s->hit && !tls1_set_server_sigalgs(s)) {
2002         /* SSLfatal() already called */
2003         goto err;
2004     }
2005 
2006     if (!s->hit
2007         && s->version >= TLS1_VERSION
2008         && !SSL_CONNECTION_IS_TLS13(s)
2009         && !SSL_CONNECTION_IS_DTLS(s)
2010         && s->ext.session_secret_cb != NULL) {
2011         const SSL_CIPHER *pref_cipher = NULL;
2012         /*
2013          * s->session->master_key_length is a size_t, but this is an int for
2014          * backwards compat reasons
2015          */
2016         int master_key_length;
2017 
2018         master_key_length = sizeof(s->session->master_key);
2019         if (s->ext.session_secret_cb(ussl, s->session->master_key,
2020                 &master_key_length, ciphers,
2021                 &pref_cipher,
2022                 s->ext.session_secret_cb_arg)
2023             && master_key_length > 0) {
2024             s->session->master_key_length = master_key_length;
2025             s->hit = 1;
2026             s->peer_ciphers = ciphers;
2027             s->session->verify_result = X509_V_OK;
2028 
2029             /*
2030              * Per RFC 4851, Section 3.2.2:
2031              * If the ClientHello contains both a Session ID and a PAC-Opaque in
2032              * the SessionTicket extension, and the server resumes the session
2033              * using the PAC-Opaque, it should echo the same Session ID in the
2034              * ServerHello.
2035              */
2036             if (clienthello->session_id_len > 0) {
2037                 memcpy(s->session->session_id, clienthello->session_id,
2038                     clienthello->session_id_len);
2039                 s->session->session_id_length = clienthello->session_id_len;
2040             }
2041 
2042             ciphers = NULL;
2043 
2044             /* check if some cipher was preferred by call back */
2045             if (pref_cipher == NULL)
2046                 pref_cipher = ssl3_choose_cipher(s, s->peer_ciphers,
2047                     SSL_get_ciphers(ssl));
2048             if (pref_cipher == NULL) {
2049                 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_NO_SHARED_CIPHER);
2050                 goto err;
2051             }
2052 
2053             s->session->cipher = pref_cipher;
2054             sk_SSL_CIPHER_free(s->cipher_list);
2055             s->cipher_list = sk_SSL_CIPHER_dup(s->peer_ciphers);
2056             sk_SSL_CIPHER_free(s->cipher_list_by_id);
2057             s->cipher_list_by_id = sk_SSL_CIPHER_dup(s->peer_ciphers);
2058         }
2059     }
2060 
2061     /*
2062      * Worst case, we will use the NULL compression, but if we have other
2063      * options, we will now look for them.  We have complen-1 compression
2064      * algorithms from the client, starting at q.
2065      */
2066     s->s3.tmp.new_compression = NULL;
2067     if (SSL_CONNECTION_IS_TLS13(s)) {
2068         /*
2069          * We already checked above that the NULL compression method appears in
2070          * the list. Now we check there aren't any others (which is illegal in
2071          * a TLSv1.3 ClientHello.
2072          */
2073         if (clienthello->compressions_len != 1) {
2074             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
2075                 SSL_R_INVALID_COMPRESSION_ALGORITHM);
2076             goto err;
2077         }
2078     }
2079 #ifndef OPENSSL_NO_COMP
2080     /* This only happens if we have a cache hit */
2081     else if (s->session->compress_meth != 0) {
2082         int m, comp_id = s->session->compress_meth;
2083         unsigned int k;
2084         /* Perform sanity checks on resumed compression algorithm */
2085         /* Can't disable compression */
2086         if (!ssl_allow_compression(s)) {
2087             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2088                 SSL_R_INCONSISTENT_COMPRESSION);
2089             goto err;
2090         }
2091         /* Look for resumed compression method */
2092         for (m = 0; m < sk_SSL_COMP_num(sctx->comp_methods); m++) {
2093             comp = sk_SSL_COMP_value(sctx->comp_methods, m);
2094             if (comp_id == comp->id) {
2095                 s->s3.tmp.new_compression = comp;
2096                 break;
2097             }
2098         }
2099         if (s->s3.tmp.new_compression == NULL) {
2100             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2101                 SSL_R_INVALID_COMPRESSION_ALGORITHM);
2102             goto err;
2103         }
2104         /* Look for resumed method in compression list */
2105         for (k = 0; k < clienthello->compressions_len; k++) {
2106             if (clienthello->compressions[k] == comp_id)
2107                 break;
2108         }
2109         if (k >= clienthello->compressions_len) {
2110             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
2111                 SSL_R_REQUIRED_COMPRESSION_ALGORITHM_MISSING);
2112             goto err;
2113         }
2114     } else if (s->hit) {
2115         comp = NULL;
2116     } else if (ssl_allow_compression(s) && sctx->comp_methods) {
2117         /* See if we have a match */
2118         int m, nn, v, done = 0;
2119         unsigned int o;
2120 
2121         nn = sk_SSL_COMP_num(sctx->comp_methods);
2122         for (m = 0; m < nn; m++) {
2123             comp = sk_SSL_COMP_value(sctx->comp_methods, m);
2124             v = comp->id;
2125             for (o = 0; o < clienthello->compressions_len; o++) {
2126                 if (v == clienthello->compressions[o]) {
2127                     done = 1;
2128                     break;
2129                 }
2130             }
2131             if (done)
2132                 break;
2133         }
2134         if (done)
2135             s->s3.tmp.new_compression = comp;
2136         else
2137             comp = NULL;
2138     }
2139 #else
2140     /*
2141      * If compression is disabled we'd better not try to resume a session
2142      * using compression.
2143      */
2144     if (s->session->compress_meth != 0) {
2145         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_INCONSISTENT_COMPRESSION);
2146         goto err;
2147     }
2148 #endif
2149 
2150     /*
2151      * Given s->peer_ciphers and SSL_get_ciphers, we must pick a cipher
2152      */
2153 
2154     if (!s->hit || SSL_CONNECTION_IS_TLS13(s)) {
2155         sk_SSL_CIPHER_free(s->peer_ciphers);
2156         s->peer_ciphers = ciphers;
2157         if (ciphers == NULL) {
2158             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2159             goto err;
2160         }
2161         ciphers = NULL;
2162     }
2163 
2164     if (!s->hit) {
2165 #ifdef OPENSSL_NO_COMP
2166         s->session->compress_meth = 0;
2167 #else
2168         s->session->compress_meth = (comp == NULL) ? 0 : comp->id;
2169 #endif
2170     }
2171 
2172     sk_SSL_CIPHER_free(ciphers);
2173     sk_SSL_CIPHER_free(scsvs);
2174     OPENSSL_free(clienthello->pre_proc_exts);
2175     OPENSSL_free(s->clienthello);
2176     s->clienthello = NULL;
2177     return 1;
2178 err:
2179     sk_SSL_CIPHER_free(ciphers);
2180     sk_SSL_CIPHER_free(scsvs);
2181     OPENSSL_free(clienthello->pre_proc_exts);
2182     OPENSSL_free(s->clienthello);
2183     s->clienthello = NULL;
2184 
2185     return 0;
2186 }
2187 
2188 /*
2189  * Call the status request callback if needed. Upon success, returns 1.
2190  * Upon failure, returns 0.
2191  */
tls_handle_status_request(SSL_CONNECTION * s)2192 static int tls_handle_status_request(SSL_CONNECTION *s)
2193 {
2194     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
2195 
2196     s->ext.status_expected = 0;
2197 
2198     /*
2199      * If status request then ask callback what to do. Note: this must be
2200      * called after servername callbacks in case the certificate has changed,
2201      * and must be called after the cipher has been chosen because this may
2202      * influence which certificate is sent
2203      */
2204     if (s->ext.status_type != TLSEXT_STATUSTYPE_nothing && sctx != NULL
2205         && sctx->ext.status_cb != NULL) {
2206         int ret;
2207 
2208         /* If no certificate can't return certificate status */
2209         if (s->s3.tmp.cert != NULL) {
2210             /*
2211              * Set current certificate to one we will use so SSL_get_certificate
2212              * et al can pick it up.
2213              */
2214             s->cert->key = s->s3.tmp.cert;
2215             ret = sctx->ext.status_cb(SSL_CONNECTION_GET_USER_SSL(s),
2216                 sctx->ext.status_arg);
2217             switch (ret) {
2218                 /* We don't want to send a status request response */
2219             case SSL_TLSEXT_ERR_NOACK:
2220                 s->ext.status_expected = 0;
2221                 break;
2222                 /* status request response should be sent */
2223             case SSL_TLSEXT_ERR_OK:
2224                 if (s->ext.ocsp.resp)
2225                     s->ext.status_expected = 1;
2226                 break;
2227                 /* something bad happened */
2228             case SSL_TLSEXT_ERR_ALERT_FATAL:
2229             default:
2230                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_CLIENTHELLO_TLSEXT);
2231                 return 0;
2232             }
2233         }
2234     }
2235 
2236     return 1;
2237 }
2238 
2239 /*
2240  * Call the alpn_select callback if needed. Upon success, returns 1.
2241  * Upon failure, returns 0.
2242  */
tls_handle_alpn(SSL_CONNECTION * s)2243 int tls_handle_alpn(SSL_CONNECTION *s)
2244 {
2245     const unsigned char *selected = NULL;
2246     unsigned char selected_len = 0;
2247     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
2248 
2249     if (sctx->ext.alpn_select_cb != NULL && s->s3.alpn_proposed != NULL) {
2250         int r = sctx->ext.alpn_select_cb(SSL_CONNECTION_GET_USER_SSL(s),
2251             &selected, &selected_len,
2252             s->s3.alpn_proposed,
2253             (unsigned int)s->s3.alpn_proposed_len,
2254             sctx->ext.alpn_select_cb_arg);
2255 
2256         if (r == SSL_TLSEXT_ERR_OK) {
2257             OPENSSL_free(s->s3.alpn_selected);
2258             s->s3.alpn_selected = OPENSSL_memdup(selected, selected_len);
2259             if (s->s3.alpn_selected == NULL) {
2260                 s->s3.alpn_selected_len = 0;
2261                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2262                 return 0;
2263             }
2264             s->s3.alpn_selected_len = selected_len;
2265 #ifndef OPENSSL_NO_NEXTPROTONEG
2266             /* ALPN takes precedence over NPN. */
2267             s->s3.npn_seen = 0;
2268 #endif
2269 
2270             /* Check ALPN is consistent with session */
2271             if (s->session->ext.alpn_selected == NULL
2272                 || selected_len != s->session->ext.alpn_selected_len
2273                 || memcmp(selected, s->session->ext.alpn_selected,
2274                        selected_len)
2275                     != 0) {
2276                 /* Not consistent so can't be used for early_data */
2277                 s->ext.early_data_ok = 0;
2278 
2279                 if (!s->hit) {
2280                     /*
2281                      * This is a new session and so alpn_selected should have
2282                      * been initialised to NULL. We should update it with the
2283                      * selected ALPN.
2284                      */
2285                     if (!ossl_assert(s->session->ext.alpn_selected == NULL)) {
2286                         SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2287                             ERR_R_INTERNAL_ERROR);
2288                         return 0;
2289                     }
2290                     s->session->ext.alpn_selected = OPENSSL_memdup(selected,
2291                         selected_len);
2292                     if (s->session->ext.alpn_selected == NULL) {
2293                         SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2294                             ERR_R_INTERNAL_ERROR);
2295                         return 0;
2296                     }
2297                     s->session->ext.alpn_selected_len = selected_len;
2298                 }
2299             }
2300 
2301             return 1;
2302         } else if (r != SSL_TLSEXT_ERR_NOACK) {
2303             SSLfatal(s, SSL_AD_NO_APPLICATION_PROTOCOL,
2304                 SSL_R_NO_APPLICATION_PROTOCOL);
2305             return 0;
2306         }
2307         /*
2308          * If r == SSL_TLSEXT_ERR_NOACK then behave as if no callback was
2309          * present.
2310          */
2311     }
2312 
2313     /* Check ALPN is consistent with session */
2314     if (s->session->ext.alpn_selected != NULL) {
2315         /* Not consistent so can't be used for early_data */
2316         s->ext.early_data_ok = 0;
2317     }
2318 
2319     return 1;
2320 }
2321 
tls_post_process_client_hello(SSL_CONNECTION * s,WORK_STATE wst)2322 WORK_STATE tls_post_process_client_hello(SSL_CONNECTION *s, WORK_STATE wst)
2323 {
2324     const SSL_CIPHER *cipher;
2325     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
2326     SSL *ussl = SSL_CONNECTION_GET_USER_SSL(s);
2327 
2328     if (wst == WORK_MORE_A) {
2329         int rv = tls_early_post_process_client_hello(s);
2330         if (rv == 0) {
2331             /* SSLfatal() was already called */
2332             goto err;
2333         }
2334         if (rv < 0)
2335             return WORK_MORE_A;
2336         wst = WORK_MORE_B;
2337     }
2338     if (wst == WORK_MORE_B) {
2339         if (!s->hit || SSL_CONNECTION_IS_TLS13(s)) {
2340             /* Let cert callback update server certificates if required */
2341             if (!s->hit && s->cert->cert_cb != NULL) {
2342                 int rv = s->cert->cert_cb(ussl, s->cert->cert_cb_arg);
2343 
2344                 if (rv == 0) {
2345                     SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_CERT_CB_ERROR);
2346                     goto err;
2347                 }
2348                 if (rv < 0) {
2349                     s->rwstate = SSL_X509_LOOKUP;
2350                     return WORK_MORE_B;
2351                 }
2352                 s->rwstate = SSL_NOTHING;
2353             }
2354 
2355             /* In TLSv1.3 we selected the ciphersuite before resumption */
2356             if (!SSL_CONNECTION_IS_TLS13(s)) {
2357                 cipher = ssl3_choose_cipher(s, s->peer_ciphers,
2358                     SSL_get_ciphers(ssl));
2359 
2360                 if (cipher == NULL) {
2361                     SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2362                         SSL_R_NO_SHARED_CIPHER);
2363                     goto err;
2364                 }
2365                 s->s3.tmp.new_cipher = cipher;
2366             }
2367             if (!s->hit) {
2368                 if (!tls_choose_sigalg(s, 1)) {
2369                     /* SSLfatal already called */
2370                     goto err;
2371                 }
2372                 /* check whether we should disable session resumption */
2373                 if (s->not_resumable_session_cb != NULL)
2374                     s->session->not_resumable = s->not_resumable_session_cb(ussl,
2375                         ((s->s3.tmp.new_cipher->algorithm_mkey
2376                              & (SSL_kDHE | SSL_kECDHE))
2377                             != 0));
2378                 if (s->session->not_resumable)
2379                     /* do not send a session ticket */
2380                     s->ext.ticket_expected = 0;
2381             }
2382         } else {
2383             /* Session-id reuse */
2384             s->s3.tmp.new_cipher = s->session->cipher;
2385         }
2386 
2387         /*-
2388          * we now have the following setup.
2389          * client_random
2390          * cipher_list          - our preferred list of ciphers
2391          * ciphers              - the client's preferred list of ciphers
2392          * compression          - basically ignored right now
2393          * ssl version is set   - sslv3
2394          * s->session           - The ssl session has been setup.
2395          * s->hit               - session reuse flag
2396          * s->s3.tmp.new_cipher - the new cipher to use.
2397          */
2398 
2399         /*
2400          * Call status_request callback if needed. Has to be done after the
2401          * certificate callbacks etc above.
2402          */
2403         if (!tls_handle_status_request(s)) {
2404             /* SSLfatal() already called */
2405             goto err;
2406         }
2407         /*
2408          * Call alpn_select callback if needed.  Has to be done after SNI and
2409          * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3
2410          * we already did this because cipher negotiation happens earlier, and
2411          * we must handle ALPN before we decide whether to accept early_data.
2412          */
2413         if (!SSL_CONNECTION_IS_TLS13(s) && !tls_handle_alpn(s)) {
2414             /* SSLfatal() already called */
2415             goto err;
2416         }
2417 
2418         wst = WORK_MORE_C;
2419     }
2420 #ifndef OPENSSL_NO_SRP
2421     if (wst == WORK_MORE_C) {
2422         int ret;
2423         if ((ret = ssl_check_srp_ext_ClientHello(s)) == 0) {
2424             /*
2425              * callback indicates further work to be done
2426              */
2427             s->rwstate = SSL_X509_LOOKUP;
2428             return WORK_MORE_C;
2429         }
2430         if (ret < 0) {
2431             /* SSLfatal() already called */
2432             goto err;
2433         }
2434     }
2435 #endif
2436 
2437     return WORK_FINISHED_STOP;
2438 err:
2439     return WORK_ERROR;
2440 }
2441 
tls_construct_server_hello(SSL_CONNECTION * s,WPACKET * pkt)2442 CON_FUNC_RETURN tls_construct_server_hello(SSL_CONNECTION *s, WPACKET *pkt)
2443 {
2444     int compm;
2445     size_t sl, len;
2446     int version;
2447     unsigned char *session_id;
2448     int usetls13 = SSL_CONNECTION_IS_TLS13(s)
2449         || s->hello_retry_request == SSL_HRR_PENDING;
2450 
2451     version = usetls13 ? TLS1_2_VERSION : s->version;
2452     if (!WPACKET_put_bytes_u16(pkt, version)
2453         /*
2454          * Random stuff. Filling of the server_random takes place in
2455          * tls_process_client_hello()
2456          */
2457         || !WPACKET_memcpy(pkt,
2458             s->hello_retry_request == SSL_HRR_PENDING
2459                 ? hrrrandom
2460                 : s->s3.server_random,
2461             SSL3_RANDOM_SIZE)) {
2462         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2463         return CON_FUNC_ERROR;
2464     }
2465 
2466     /*-
2467      * There are several cases for the session ID to send
2468      * back in the server hello:
2469      * - For session reuse from the session cache,
2470      *   we send back the old session ID.
2471      * - If stateless session reuse (using a session ticket)
2472      *   is successful, we send back the client's "session ID"
2473      *   (which doesn't actually identify the session).
2474      * - If it is a new session, we send back the new
2475      *   session ID.
2476      * - However, if we want the new session to be single-use,
2477      *   we send back a 0-length session ID.
2478      * - In TLSv1.3 we echo back the session id sent to us by the client
2479      *   regardless
2480      * s->hit is non-zero in either case of session reuse,
2481      * so the following won't overwrite an ID that we're supposed
2482      * to send back.
2483      */
2484     if (!(SSL_CONNECTION_GET_CTX(s)->session_cache_mode & SSL_SESS_CACHE_SERVER)
2485         && !s->hit)
2486         s->session->session_id_length = 0;
2487 
2488     if (usetls13) {
2489         sl = s->tmp_session_id_len;
2490         session_id = s->tmp_session_id;
2491     } else {
2492         sl = s->session->session_id_length;
2493         session_id = s->session->session_id;
2494     }
2495 
2496     if (sl > sizeof(s->session->session_id)) {
2497         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2498         return CON_FUNC_ERROR;
2499     }
2500 
2501     /* set up the compression method */
2502 #ifdef OPENSSL_NO_COMP
2503     compm = 0;
2504 #else
2505     if (usetls13 || s->s3.tmp.new_compression == NULL)
2506         compm = 0;
2507     else
2508         compm = s->s3.tmp.new_compression->id;
2509 #endif
2510 
2511     if (!WPACKET_sub_memcpy_u8(pkt, session_id, sl)
2512         || !SSL_CONNECTION_GET_SSL(s)->method->put_cipher_by_char(s->s3.tmp.new_cipher,
2513             pkt, &len)
2514         || !WPACKET_put_bytes_u8(pkt, compm)) {
2515         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2516         return CON_FUNC_ERROR;
2517     }
2518 
2519     if (!tls_construct_extensions(s, pkt,
2520             s->hello_retry_request == SSL_HRR_PENDING
2521                 ? SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
2522                 : (SSL_CONNECTION_IS_TLS13(s)
2523                           ? SSL_EXT_TLS1_3_SERVER_HELLO
2524                           : SSL_EXT_TLS1_2_SERVER_HELLO),
2525             NULL, 0)) {
2526         /* SSLfatal() already called */
2527         return CON_FUNC_ERROR;
2528     }
2529 
2530     if (s->hello_retry_request == SSL_HRR_PENDING) {
2531         /* Ditch the session. We'll create a new one next time around */
2532         SSL_SESSION_free(s->session);
2533         s->session = NULL;
2534         s->hit = 0;
2535 
2536         /*
2537          * Re-initialise the Transcript Hash. We're going to prepopulate it with
2538          * a synthetic message_hash in place of ClientHello1.
2539          */
2540         if (!create_synthetic_message_hash(s, NULL, 0, NULL, 0)) {
2541             /* SSLfatal() already called */
2542             return CON_FUNC_ERROR;
2543         }
2544     } else if (!(s->verify_mode & SSL_VERIFY_PEER)
2545         && !ssl3_digest_cached_records(s, 0)) {
2546         /* SSLfatal() already called */;
2547         return CON_FUNC_ERROR;
2548     }
2549 
2550     return CON_FUNC_SUCCESS;
2551 }
2552 
tls_construct_server_done(SSL_CONNECTION * s,WPACKET * pkt)2553 CON_FUNC_RETURN tls_construct_server_done(SSL_CONNECTION *s, WPACKET *pkt)
2554 {
2555     if (!s->s3.tmp.cert_request) {
2556         if (!ssl3_digest_cached_records(s, 0)) {
2557             /* SSLfatal() already called */
2558             return CON_FUNC_ERROR;
2559         }
2560     }
2561     return CON_FUNC_SUCCESS;
2562 }
2563 
tls_construct_server_key_exchange(SSL_CONNECTION * s,WPACKET * pkt)2564 CON_FUNC_RETURN tls_construct_server_key_exchange(SSL_CONNECTION *s,
2565     WPACKET *pkt)
2566 {
2567     EVP_PKEY *pkdh = NULL;
2568     unsigned char *encodedPoint = NULL;
2569     size_t encodedlen = 0;
2570     int curve_id = 0;
2571     const SIGALG_LOOKUP *lu = s->s3.tmp.sigalg;
2572     int i;
2573     unsigned long type;
2574     BIGNUM *r[4];
2575     EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
2576     EVP_PKEY_CTX *pctx = NULL;
2577     size_t paramlen, paramoffset;
2578     int freer = 0;
2579     CON_FUNC_RETURN ret = CON_FUNC_ERROR;
2580     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
2581 
2582     if (!WPACKET_get_total_written(pkt, &paramoffset)) {
2583         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2584         goto err;
2585     }
2586 
2587     if (md_ctx == NULL) {
2588         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
2589         goto err;
2590     }
2591 
2592     type = s->s3.tmp.new_cipher->algorithm_mkey;
2593 
2594     r[0] = r[1] = r[2] = r[3] = NULL;
2595 #ifndef OPENSSL_NO_PSK
2596     /* Plain PSK or RSAPSK nothing to do */
2597     if (type & (SSL_kPSK | SSL_kRSAPSK)) {
2598     } else
2599 #endif /* !OPENSSL_NO_PSK */
2600         if (type & (SSL_kDHE | SSL_kDHEPSK)) {
2601             CERT *cert = s->cert;
2602             EVP_PKEY *pkdhp = NULL;
2603 
2604             if (s->cert->dh_tmp_auto) {
2605                 pkdh = ssl_get_auto_dh(s);
2606                 if (pkdh == NULL) {
2607                     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2608                     goto err;
2609                 }
2610                 pkdhp = pkdh;
2611             } else {
2612                 pkdhp = cert->dh_tmp;
2613             }
2614 #if !defined(OPENSSL_NO_DEPRECATED_3_0)
2615             if ((pkdhp == NULL) && (s->cert->dh_tmp_cb != NULL)) {
2616                 pkdh = ssl_dh_to_pkey(s->cert->dh_tmp_cb(SSL_CONNECTION_GET_USER_SSL(s),
2617                     0, 1024));
2618                 if (pkdh == NULL) {
2619                     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2620                     goto err;
2621                 }
2622                 pkdhp = pkdh;
2623             }
2624 #endif
2625             if (pkdhp == NULL) {
2626                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_TMP_DH_KEY);
2627                 goto err;
2628             }
2629             if (!ssl_security(s, SSL_SECOP_TMP_DH,
2630                     EVP_PKEY_get_security_bits(pkdhp), 0, pkdhp)) {
2631                 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_DH_KEY_TOO_SMALL);
2632                 goto err;
2633             }
2634             if (s->s3.tmp.pkey != NULL) {
2635                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2636                 goto err;
2637             }
2638 
2639             s->s3.tmp.pkey = ssl_generate_pkey(s, pkdhp);
2640             if (s->s3.tmp.pkey == NULL) {
2641                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2642                 goto err;
2643             }
2644 
2645             EVP_PKEY_free(pkdh);
2646             pkdh = NULL;
2647 
2648             /* These BIGNUMs need to be freed when we're finished */
2649             freer = 1;
2650             if (!EVP_PKEY_get_bn_param(s->s3.tmp.pkey, OSSL_PKEY_PARAM_FFC_P,
2651                     &r[0])
2652                 || !EVP_PKEY_get_bn_param(s->s3.tmp.pkey, OSSL_PKEY_PARAM_FFC_G,
2653                     &r[1])
2654                 || !EVP_PKEY_get_bn_param(s->s3.tmp.pkey,
2655                     OSSL_PKEY_PARAM_PUB_KEY, &r[2])) {
2656                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2657                 goto err;
2658             }
2659         } else if (type & (SSL_kECDHE | SSL_kECDHEPSK)) {
2660 
2661             if (s->s3.tmp.pkey != NULL) {
2662                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2663                 goto err;
2664             }
2665 
2666             /* Get NID of appropriate shared curve */
2667             curve_id = tls1_shared_group(s, -2);
2668             if (curve_id == 0) {
2669                 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2670                     SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
2671                 goto err;
2672             }
2673             /* Cache the group used in the SSL_SESSION */
2674             s->session->kex_group = curve_id;
2675             /* Generate a new key for this curve */
2676             s->s3.tmp.pkey = ssl_generate_pkey_group(s, curve_id);
2677             if (s->s3.tmp.pkey == NULL) {
2678                 /* SSLfatal() already called */
2679                 goto err;
2680             }
2681 
2682             /* Encode the public key. */
2683             encodedlen = EVP_PKEY_get1_encoded_public_key(s->s3.tmp.pkey,
2684                 &encodedPoint);
2685             if (encodedlen == 0) {
2686                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EC_LIB);
2687                 goto err;
2688             }
2689 
2690             /*
2691              * We'll generate the serverKeyExchange message explicitly so we
2692              * can set these to NULLs
2693              */
2694             r[0] = NULL;
2695             r[1] = NULL;
2696             r[2] = NULL;
2697             r[3] = NULL;
2698         } else
2699 #ifndef OPENSSL_NO_SRP
2700             if (type & SSL_kSRP) {
2701             if ((s->srp_ctx.N == NULL) || (s->srp_ctx.g == NULL) || (s->srp_ctx.s == NULL) || (s->srp_ctx.B == NULL)) {
2702                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_SRP_PARAM);
2703                 goto err;
2704             }
2705             r[0] = s->srp_ctx.N;
2706             r[1] = s->srp_ctx.g;
2707             r[2] = s->srp_ctx.s;
2708             r[3] = s->srp_ctx.B;
2709         } else
2710 #endif
2711         {
2712             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
2713             goto err;
2714         }
2715 
2716     if (((s->s3.tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP)) != 0)
2717         || ((s->s3.tmp.new_cipher->algorithm_mkey & SSL_PSK)) != 0) {
2718         lu = NULL;
2719     } else if (lu == NULL) {
2720         SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_INTERNAL_ERROR);
2721         goto err;
2722     }
2723 
2724 #ifndef OPENSSL_NO_PSK
2725     if (type & SSL_PSK) {
2726         size_t len = (s->cert->psk_identity_hint == NULL)
2727             ? 0
2728             : strlen(s->cert->psk_identity_hint);
2729 
2730         /*
2731          * It should not happen that len > PSK_MAX_IDENTITY_LEN - we already
2732          * checked this when we set the identity hint - but just in case
2733          */
2734         if (len > PSK_MAX_IDENTITY_LEN
2735             || !WPACKET_sub_memcpy_u16(pkt, s->cert->psk_identity_hint,
2736                 len)) {
2737             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2738             goto err;
2739         }
2740     }
2741 #endif
2742 
2743     for (i = 0; i < 4 && r[i] != NULL; i++) {
2744         unsigned char *binval;
2745         int res;
2746 
2747 #ifndef OPENSSL_NO_SRP
2748         if ((i == 2) && (type & SSL_kSRP)) {
2749             res = WPACKET_start_sub_packet_u8(pkt);
2750         } else
2751 #endif
2752             res = WPACKET_start_sub_packet_u16(pkt);
2753 
2754         if (!res) {
2755             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2756             goto err;
2757         }
2758 
2759         /*-
2760          * for interoperability with some versions of the Microsoft TLS
2761          * stack, we need to zero pad the DHE pub key to the same length
2762          * as the prime
2763          */
2764         if ((i == 2) && (type & (SSL_kDHE | SSL_kDHEPSK))) {
2765             size_t len = BN_num_bytes(r[0]) - BN_num_bytes(r[2]);
2766 
2767             if (len > 0) {
2768                 if (!WPACKET_allocate_bytes(pkt, len, &binval)) {
2769                     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2770                     goto err;
2771                 }
2772                 memset(binval, 0, len);
2773             }
2774         }
2775 
2776         if (!WPACKET_allocate_bytes(pkt, BN_num_bytes(r[i]), &binval)
2777             || !WPACKET_close(pkt)) {
2778             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2779             goto err;
2780         }
2781 
2782         BN_bn2bin(r[i], binval);
2783     }
2784 
2785     if (type & (SSL_kECDHE | SSL_kECDHEPSK)) {
2786         /*
2787          * We only support named (not generic) curves. In this situation, the
2788          * ServerKeyExchange message has: [1 byte CurveType], [2 byte CurveName]
2789          * [1 byte length of encoded point], followed by the actual encoded
2790          * point itself
2791          */
2792         if (!WPACKET_put_bytes_u8(pkt, NAMED_CURVE_TYPE)
2793             || !WPACKET_put_bytes_u8(pkt, 0)
2794             || !WPACKET_put_bytes_u8(pkt, curve_id)
2795             || !WPACKET_sub_memcpy_u8(pkt, encodedPoint, encodedlen)) {
2796             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2797             goto err;
2798         }
2799         OPENSSL_free(encodedPoint);
2800         encodedPoint = NULL;
2801     }
2802 
2803     /* not anonymous */
2804     if (lu != NULL) {
2805         EVP_PKEY *pkey = s->s3.tmp.cert->privatekey;
2806         const EVP_MD *md;
2807         unsigned char *sigbytes1, *sigbytes2, *tbs;
2808         size_t siglen = 0, tbslen;
2809 
2810         if (pkey == NULL || !tls1_lookup_md(sctx, lu, &md)) {
2811             /* Should never happen */
2812             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2813             goto err;
2814         }
2815         /* Get length of the parameters we have written above */
2816         if (!WPACKET_get_length(pkt, &paramlen)) {
2817             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2818             goto err;
2819         }
2820         /* send signature algorithm */
2821         if (SSL_USE_SIGALGS(s) && !WPACKET_put_bytes_u16(pkt, lu->sigalg)) {
2822             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2823             goto err;
2824         }
2825 
2826         if (EVP_DigestSignInit_ex(md_ctx, &pctx,
2827                 md == NULL ? NULL : EVP_MD_get0_name(md),
2828                 sctx->libctx, sctx->propq, pkey,
2829                 NULL)
2830             <= 0) {
2831             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2832             goto err;
2833         }
2834         if (lu->sig == EVP_PKEY_RSA_PSS) {
2835             if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
2836                 || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, RSA_PSS_SALTLEN_DIGEST) <= 0) {
2837                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
2838                 goto err;
2839             }
2840         }
2841         tbslen = construct_key_exchange_tbs(s, &tbs,
2842             s->init_buf->data + paramoffset,
2843             paramlen);
2844         if (tbslen == 0) {
2845             /* SSLfatal() already called */
2846             goto err;
2847         }
2848 
2849         if (EVP_DigestSign(md_ctx, NULL, &siglen, tbs, tbslen) <= 0
2850             || !WPACKET_sub_reserve_bytes_u16(pkt, siglen, &sigbytes1)
2851             || EVP_DigestSign(md_ctx, sigbytes1, &siglen, tbs, tbslen) <= 0
2852             || !WPACKET_sub_allocate_bytes_u16(pkt, siglen, &sigbytes2)
2853             || sigbytes1 != sigbytes2) {
2854             OPENSSL_free(tbs);
2855             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2856             goto err;
2857         }
2858         OPENSSL_free(tbs);
2859     }
2860 
2861     ret = CON_FUNC_SUCCESS;
2862 err:
2863     EVP_PKEY_free(pkdh);
2864     OPENSSL_free(encodedPoint);
2865     EVP_MD_CTX_free(md_ctx);
2866     if (freer) {
2867         BN_free(r[0]);
2868         BN_free(r[1]);
2869         BN_free(r[2]);
2870         BN_free(r[3]);
2871     }
2872     return ret;
2873 }
2874 
tls_construct_certificate_request(SSL_CONNECTION * s,WPACKET * pkt)2875 CON_FUNC_RETURN tls_construct_certificate_request(SSL_CONNECTION *s,
2876     WPACKET *pkt)
2877 {
2878     if (SSL_CONNECTION_IS_TLS13(s)) {
2879         /* Send random context when doing post-handshake auth */
2880         if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) {
2881             OPENSSL_free(s->pha_context);
2882             s->pha_context_len = 32;
2883             if ((s->pha_context = OPENSSL_malloc(s->pha_context_len)) == NULL) {
2884                 s->pha_context_len = 0;
2885                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2886                 return CON_FUNC_ERROR;
2887             }
2888             if (RAND_bytes_ex(SSL_CONNECTION_GET_CTX(s)->libctx,
2889                     s->pha_context, s->pha_context_len, 0)
2890                     <= 0
2891                 || !WPACKET_sub_memcpy_u8(pkt, s->pha_context,
2892                     s->pha_context_len)) {
2893                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2894                 return CON_FUNC_ERROR;
2895             }
2896             /* reset the handshake hash back to just after the ClientFinished */
2897             if (!tls13_restore_handshake_digest_for_pha(s)) {
2898                 /* SSLfatal() already called */
2899                 return CON_FUNC_ERROR;
2900             }
2901         } else {
2902             if (!WPACKET_put_bytes_u8(pkt, 0)) {
2903                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2904                 return CON_FUNC_ERROR;
2905             }
2906         }
2907 
2908         if (!tls_construct_extensions(s, pkt,
2909                 SSL_EXT_TLS1_3_CERTIFICATE_REQUEST, NULL,
2910                 0)) {
2911             /* SSLfatal() already called */
2912             return CON_FUNC_ERROR;
2913         }
2914         goto done;
2915     }
2916 
2917     /* get the list of acceptable cert types */
2918     if (!WPACKET_start_sub_packet_u8(pkt)
2919         || !ssl3_get_req_cert_type(s, pkt) || !WPACKET_close(pkt)) {
2920         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2921         return CON_FUNC_ERROR;
2922     }
2923 
2924     if (SSL_USE_SIGALGS(s)) {
2925         const uint16_t *psigs;
2926         size_t nl = tls12_get_psigalgs(s, 1, &psigs);
2927 
2928         if (!WPACKET_start_sub_packet_u16(pkt)
2929             || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH)
2930             || !tls12_copy_sigalgs(s, pkt, psigs, nl)
2931             || !WPACKET_close(pkt)) {
2932             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2933             return CON_FUNC_ERROR;
2934         }
2935     }
2936 
2937     if (!construct_ca_names(s, get_ca_names(s), pkt)) {
2938         /* SSLfatal() already called */
2939         return CON_FUNC_ERROR;
2940     }
2941 
2942 done:
2943     s->certreqs_sent++;
2944     s->s3.tmp.cert_request = 1;
2945     return CON_FUNC_SUCCESS;
2946 }
2947 
tls_process_cke_psk_preamble(SSL_CONNECTION * s,PACKET * pkt)2948 static int tls_process_cke_psk_preamble(SSL_CONNECTION *s, PACKET *pkt)
2949 {
2950 #ifndef OPENSSL_NO_PSK
2951     unsigned char psk[PSK_MAX_PSK_LEN];
2952     size_t psklen;
2953     PACKET psk_identity;
2954 
2955     if (!PACKET_get_length_prefixed_2(pkt, &psk_identity)) {
2956         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2957         return 0;
2958     }
2959     if (PACKET_remaining(&psk_identity) > PSK_MAX_IDENTITY_LEN) {
2960         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DATA_LENGTH_TOO_LONG);
2961         return 0;
2962     }
2963     if (s->psk_server_callback == NULL) {
2964         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PSK_NO_SERVER_CB);
2965         return 0;
2966     }
2967 
2968     if (!PACKET_strndup(&psk_identity, &s->session->psk_identity)) {
2969         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2970         return 0;
2971     }
2972 
2973     psklen = s->psk_server_callback(SSL_CONNECTION_GET_USER_SSL(s),
2974         s->session->psk_identity,
2975         psk, sizeof(psk));
2976 
2977     if (psklen > PSK_MAX_PSK_LEN) {
2978         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2979         return 0;
2980     } else if (psklen == 0) {
2981         /*
2982          * PSK related to the given identity not found
2983          */
2984         SSLfatal(s, SSL_AD_UNKNOWN_PSK_IDENTITY, SSL_R_PSK_IDENTITY_NOT_FOUND);
2985         return 0;
2986     }
2987 
2988     OPENSSL_free(s->s3.tmp.psk);
2989     s->s3.tmp.psk = OPENSSL_memdup(psk, psklen);
2990     OPENSSL_cleanse(psk, psklen);
2991 
2992     if (s->s3.tmp.psk == NULL) {
2993         s->s3.tmp.psklen = 0;
2994         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
2995         return 0;
2996     }
2997 
2998     s->s3.tmp.psklen = psklen;
2999 
3000     return 1;
3001 #else
3002     /* Should never happen */
3003     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3004     return 0;
3005 #endif
3006 }
3007 
tls_process_cke_rsa(SSL_CONNECTION * s,PACKET * pkt)3008 static int tls_process_cke_rsa(SSL_CONNECTION *s, PACKET *pkt)
3009 {
3010     size_t outlen;
3011     PACKET enc_premaster;
3012     EVP_PKEY *rsa = NULL;
3013     unsigned char *rsa_decrypt = NULL;
3014     int ret = 0;
3015     EVP_PKEY_CTX *ctx = NULL;
3016     OSSL_PARAM params[3], *p = params;
3017     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
3018 
3019     rsa = s->cert->pkeys[SSL_PKEY_RSA].privatekey;
3020     if (rsa == NULL) {
3021         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_RSA_CERTIFICATE);
3022         return 0;
3023     }
3024 
3025     /* SSLv3 and pre-standard DTLS omit the length bytes. */
3026     if (s->version == SSL3_VERSION || s->version == DTLS1_BAD_VER) {
3027         enc_premaster = *pkt;
3028     } else {
3029         if (!PACKET_get_length_prefixed_2(pkt, &enc_premaster)
3030             || PACKET_remaining(pkt) != 0) {
3031             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3032             return 0;
3033         }
3034     }
3035 
3036     outlen = SSL_MAX_MASTER_KEY_LENGTH;
3037     rsa_decrypt = OPENSSL_malloc(outlen);
3038     if (rsa_decrypt == NULL) {
3039         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
3040         return 0;
3041     }
3042 
3043     ctx = EVP_PKEY_CTX_new_from_pkey(sctx->libctx, rsa, sctx->propq);
3044     if (ctx == NULL) {
3045         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
3046         goto err;
3047     }
3048 
3049     /*
3050      * We must not leak whether a decryption failure occurs because of
3051      * Bleichenbacher's attack on PKCS #1 v1.5 RSA padding (see RFC 2246,
3052      * section 7.4.7.1). We use the special padding type
3053      * RSA_PKCS1_WITH_TLS_PADDING to do that. It will automatically decrypt the
3054      * RSA, check the padding and check that the client version is as expected
3055      * in the premaster secret. If any of that fails then the function appears
3056      * to return successfully but with a random result. The call below could
3057      * still fail if the input is publicly invalid.
3058      * See https://tools.ietf.org/html/rfc5246#section-7.4.7.1
3059      */
3060     if (EVP_PKEY_decrypt_init(ctx) <= 0
3061         || EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_WITH_TLS_PADDING) <= 0) {
3062         SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_R_DECRYPTION_FAILED);
3063         goto err;
3064     }
3065 
3066     *p++ = OSSL_PARAM_construct_uint(OSSL_ASYM_CIPHER_PARAM_TLS_CLIENT_VERSION,
3067         (unsigned int *)&s->client_version);
3068     if ((s->options & SSL_OP_TLS_ROLLBACK_BUG) != 0)
3069         *p++ = OSSL_PARAM_construct_uint(
3070             OSSL_ASYM_CIPHER_PARAM_TLS_NEGOTIATED_VERSION,
3071             (unsigned int *)&s->version);
3072     *p++ = OSSL_PARAM_construct_end();
3073 
3074     if (!EVP_PKEY_CTX_set_params(ctx, params)
3075         || EVP_PKEY_decrypt(ctx, rsa_decrypt, &outlen,
3076                PACKET_data(&enc_premaster),
3077                PACKET_remaining(&enc_premaster))
3078             <= 0) {
3079         SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_R_DECRYPTION_FAILED);
3080         goto err;
3081     }
3082 
3083     /*
3084      * This test should never fail (otherwise we should have failed above) but
3085      * we double check anyway.
3086      */
3087     if (outlen != SSL_MAX_MASTER_KEY_LENGTH) {
3088         OPENSSL_cleanse(rsa_decrypt, SSL_MAX_MASTER_KEY_LENGTH);
3089         SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_R_DECRYPTION_FAILED);
3090         goto err;
3091     }
3092 
3093     /* Also cleanses rsa_decrypt (on success or failure) */
3094     if (!ssl_generate_master_secret(s, rsa_decrypt, outlen, 0)) {
3095         /* SSLfatal() already called */
3096         goto err;
3097     }
3098 
3099     ret = 1;
3100 err:
3101     OPENSSL_free(rsa_decrypt);
3102     EVP_PKEY_CTX_free(ctx);
3103     return ret;
3104 }
3105 
tls_process_cke_dhe(SSL_CONNECTION * s,PACKET * pkt)3106 static int tls_process_cke_dhe(SSL_CONNECTION *s, PACKET *pkt)
3107 {
3108     EVP_PKEY *skey = NULL;
3109     unsigned int i;
3110     const unsigned char *data;
3111     EVP_PKEY *ckey = NULL;
3112     int ret = 0;
3113 
3114     if (!PACKET_get_net_2(pkt, &i) || PACKET_remaining(pkt) != i) {
3115         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG);
3116         goto err;
3117     }
3118     skey = s->s3.tmp.pkey;
3119     if (skey == NULL) {
3120         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_TMP_DH_KEY);
3121         goto err;
3122     }
3123 
3124     if (PACKET_remaining(pkt) == 0L) {
3125         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_MISSING_TMP_DH_KEY);
3126         goto err;
3127     }
3128     if (!PACKET_get_bytes(pkt, &data, i)) {
3129         /* We already checked we have enough data */
3130         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3131         goto err;
3132     }
3133     ckey = EVP_PKEY_new();
3134     if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) == 0) {
3135         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COPY_PARAMETERS_FAILED);
3136         goto err;
3137     }
3138 
3139     if (EVP_PKEY_set1_encoded_public_key(ckey, data, i) <= 0) {
3140         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
3141         goto err;
3142     }
3143 
3144     if (ssl_derive(s, skey, ckey, 1) == 0) {
3145         /* SSLfatal() already called */
3146         goto err;
3147     }
3148 
3149     ret = 1;
3150     EVP_PKEY_free(s->s3.tmp.pkey);
3151     s->s3.tmp.pkey = NULL;
3152 err:
3153     EVP_PKEY_free(ckey);
3154     return ret;
3155 }
3156 
tls_process_cke_ecdhe(SSL_CONNECTION * s,PACKET * pkt)3157 static int tls_process_cke_ecdhe(SSL_CONNECTION *s, PACKET *pkt)
3158 {
3159     EVP_PKEY *skey = s->s3.tmp.pkey;
3160     EVP_PKEY *ckey = NULL;
3161     int ret = 0;
3162 
3163     if (PACKET_remaining(pkt) == 0L) {
3164         /* We don't support ECDH client auth */
3165         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_MISSING_TMP_ECDH_KEY);
3166         goto err;
3167     } else {
3168         unsigned int i;
3169         const unsigned char *data;
3170 
3171         /*
3172          * Get client's public key from encoded point in the
3173          * ClientKeyExchange message.
3174          */
3175 
3176         /* Get encoded point length */
3177         if (!PACKET_get_1(pkt, &i) || !PACKET_get_bytes(pkt, &data, i)
3178             || PACKET_remaining(pkt) != 0) {
3179             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3180             goto err;
3181         }
3182         if (skey == NULL) {
3183             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_TMP_ECDH_KEY);
3184             goto err;
3185         }
3186 
3187         ckey = EVP_PKEY_new();
3188         if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) <= 0) {
3189             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COPY_PARAMETERS_FAILED);
3190             goto err;
3191         }
3192 
3193         if (EVP_PKEY_set1_encoded_public_key(ckey, data, i) <= 0) {
3194             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
3195             goto err;
3196         }
3197     }
3198 
3199     if (ssl_derive(s, skey, ckey, 1) == 0) {
3200         /* SSLfatal() already called */
3201         goto err;
3202     }
3203 
3204     ret = 1;
3205     EVP_PKEY_free(s->s3.tmp.pkey);
3206     s->s3.tmp.pkey = NULL;
3207 err:
3208     EVP_PKEY_free(ckey);
3209 
3210     return ret;
3211 }
3212 
tls_process_cke_srp(SSL_CONNECTION * s,PACKET * pkt)3213 static int tls_process_cke_srp(SSL_CONNECTION *s, PACKET *pkt)
3214 {
3215 #ifndef OPENSSL_NO_SRP
3216     unsigned int i;
3217     const unsigned char *data;
3218 
3219     if (!PACKET_get_net_2(pkt, &i)
3220         || !PACKET_get_bytes(pkt, &data, i)) {
3221         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_SRP_A_LENGTH);
3222         return 0;
3223     }
3224     if ((s->srp_ctx.A = BN_bin2bn(data, i, NULL)) == NULL) {
3225         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BN_LIB);
3226         return 0;
3227     }
3228     if (BN_ucmp(s->srp_ctx.A, s->srp_ctx.N) >= 0 || BN_is_zero(s->srp_ctx.A)) {
3229         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_SRP_PARAMETERS);
3230         return 0;
3231     }
3232     OPENSSL_free(s->session->srp_username);
3233     s->session->srp_username = OPENSSL_strdup(s->srp_ctx.login);
3234     if (s->session->srp_username == NULL) {
3235         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
3236         return 0;
3237     }
3238 
3239     if (!srp_generate_server_master_secret(s)) {
3240         /* SSLfatal() already called */
3241         return 0;
3242     }
3243 
3244     return 1;
3245 #else
3246     /* Should never happen */
3247     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3248     return 0;
3249 #endif
3250 }
3251 
tls_process_cke_gost(SSL_CONNECTION * s,PACKET * pkt)3252 static int tls_process_cke_gost(SSL_CONNECTION *s, PACKET *pkt)
3253 {
3254 #ifndef OPENSSL_NO_GOST
3255     EVP_PKEY_CTX *pkey_ctx;
3256     EVP_PKEY *client_pub_pkey = NULL, *pk = NULL;
3257     unsigned char premaster_secret[32];
3258     const unsigned char *start;
3259     size_t outlen = sizeof(premaster_secret), inlen;
3260     unsigned long alg_a;
3261     GOST_KX_MESSAGE *pKX = NULL;
3262     const unsigned char *ptr;
3263     int ret = 0;
3264     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
3265 
3266     /* Get our certificate private key */
3267     alg_a = s->s3.tmp.new_cipher->algorithm_auth;
3268     if (alg_a & SSL_aGOST12) {
3269         /*
3270          * New GOST ciphersuites have SSL_aGOST01 bit too
3271          */
3272         pk = s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey;
3273         if (pk == NULL) {
3274             pk = s->cert->pkeys[SSL_PKEY_GOST12_256].privatekey;
3275         }
3276         if (pk == NULL) {
3277             pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
3278         }
3279     } else if (alg_a & SSL_aGOST01) {
3280         pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
3281     }
3282 
3283     pkey_ctx = EVP_PKEY_CTX_new_from_pkey(sctx->libctx, pk, sctx->propq);
3284     if (pkey_ctx == NULL) {
3285         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
3286         return 0;
3287     }
3288     if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) {
3289         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3290         goto err;
3291     }
3292     /*
3293      * If client certificate is present and is of the same type, maybe
3294      * use it for key exchange.  Don't mind errors from
3295      * EVP_PKEY_derive_set_peer, because it is completely valid to use a
3296      * client certificate for authorization only.
3297      */
3298     client_pub_pkey = tls_get_peer_pkey(s);
3299     if (client_pub_pkey) {
3300         if (EVP_PKEY_derive_set_peer(pkey_ctx, client_pub_pkey) <= 0)
3301             ERR_clear_error();
3302     }
3303 
3304     ptr = PACKET_data(pkt);
3305     /* Some implementations provide extra data in the opaqueBlob
3306      * We have nothing to do with this blob so we just skip it */
3307     pKX = d2i_GOST_KX_MESSAGE(NULL, &ptr, PACKET_remaining(pkt));
3308     if (pKX == NULL
3309         || pKX->kxBlob == NULL
3310         || ASN1_TYPE_get(pKX->kxBlob) != V_ASN1_SEQUENCE) {
3311         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DECRYPTION_FAILED);
3312         goto err;
3313     }
3314 
3315     if (!PACKET_forward(pkt, ptr - PACKET_data(pkt))) {
3316         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_DECRYPTION_FAILED);
3317         goto err;
3318     }
3319 
3320     if (PACKET_remaining(pkt) != 0) {
3321         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_DECRYPTION_FAILED);
3322         goto err;
3323     }
3324 
3325     inlen = pKX->kxBlob->value.sequence->length;
3326     start = pKX->kxBlob->value.sequence->data;
3327 
3328     if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, start,
3329             inlen)
3330         <= 0) {
3331         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DECRYPTION_FAILED);
3332         goto err;
3333     }
3334     /* Generate master secret */
3335     if (!ssl_generate_master_secret(s, premaster_secret, outlen, 0)) {
3336         /* SSLfatal() already called */
3337         goto err;
3338     }
3339     /* Check if pubkey from client certificate was used */
3340     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2,
3341             NULL)
3342         > 0)
3343         s->statem.no_cert_verify = 1;
3344 
3345     ret = 1;
3346 err:
3347     EVP_PKEY_CTX_free(pkey_ctx);
3348     GOST_KX_MESSAGE_free(pKX);
3349     return ret;
3350 #else
3351     /* Should never happen */
3352     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3353     return 0;
3354 #endif
3355 }
3356 
tls_process_cke_gost18(SSL_CONNECTION * s,PACKET * pkt)3357 static int tls_process_cke_gost18(SSL_CONNECTION *s, PACKET *pkt)
3358 {
3359 #ifndef OPENSSL_NO_GOST
3360     unsigned char rnd_dgst[32];
3361     EVP_PKEY_CTX *pkey_ctx = NULL;
3362     EVP_PKEY *pk = NULL;
3363     unsigned char premaster_secret[32];
3364     const unsigned char *start = NULL;
3365     size_t outlen = sizeof(premaster_secret), inlen = 0;
3366     int ret = 0;
3367     int cipher_nid = ossl_gost18_cke_cipher_nid(s);
3368     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
3369 
3370     if (cipher_nid == NID_undef) {
3371         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3372         return 0;
3373     }
3374 
3375     if (ossl_gost_ukm(s, rnd_dgst) <= 0) {
3376         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3377         goto err;
3378     }
3379 
3380     /* Get our certificate private key */
3381     pk = s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey != NULL ? s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey : s->cert->pkeys[SSL_PKEY_GOST12_256].privatekey;
3382     if (pk == NULL) {
3383         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_STATE);
3384         goto err;
3385     }
3386 
3387     pkey_ctx = EVP_PKEY_CTX_new_from_pkey(sctx->libctx, pk, sctx->propq);
3388     if (pkey_ctx == NULL) {
3389         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
3390         goto err;
3391     }
3392     if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) {
3393         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3394         goto err;
3395     }
3396 
3397     /* Reuse EVP_PKEY_CTRL_SET_IV, make choice in engine code depending on size */
3398     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_DECRYPT,
3399             EVP_PKEY_CTRL_SET_IV, 32, rnd_dgst)
3400         <= 0) {
3401         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
3402         goto err;
3403     }
3404 
3405     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_DECRYPT,
3406             EVP_PKEY_CTRL_CIPHER, cipher_nid, NULL)
3407         <= 0) {
3408         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
3409         goto err;
3410     }
3411     inlen = PACKET_remaining(pkt);
3412     start = PACKET_data(pkt);
3413 
3414     if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, start, inlen) <= 0) {
3415         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_DECRYPTION_FAILED);
3416         goto err;
3417     }
3418     /* Generate master secret */
3419     if (!ssl_generate_master_secret(s, premaster_secret, outlen, 0)) {
3420         /* SSLfatal() already called */
3421         goto err;
3422     }
3423     ret = 1;
3424 
3425 err:
3426     EVP_PKEY_CTX_free(pkey_ctx);
3427     return ret;
3428 #else
3429     /* Should never happen */
3430     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3431     return 0;
3432 #endif
3433 }
3434 
tls_process_client_key_exchange(SSL_CONNECTION * s,PACKET * pkt)3435 MSG_PROCESS_RETURN tls_process_client_key_exchange(SSL_CONNECTION *s,
3436     PACKET *pkt)
3437 {
3438     unsigned long alg_k;
3439 
3440     alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
3441 
3442     /* For PSK parse and retrieve identity, obtain PSK key */
3443     if ((alg_k & SSL_PSK) && !tls_process_cke_psk_preamble(s, pkt)) {
3444         /* SSLfatal() already called */
3445         goto err;
3446     }
3447 
3448     if (alg_k & SSL_kPSK) {
3449         /* Identity extracted earlier: should be nothing left */
3450         if (PACKET_remaining(pkt) != 0) {
3451             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3452             goto err;
3453         }
3454         /* PSK handled by ssl_generate_master_secret */
3455         if (!ssl_generate_master_secret(s, NULL, 0, 0)) {
3456             /* SSLfatal() already called */
3457             goto err;
3458         }
3459     } else if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) {
3460         if (!tls_process_cke_rsa(s, pkt)) {
3461             /* SSLfatal() already called */
3462             goto err;
3463         }
3464     } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
3465         if (!tls_process_cke_dhe(s, pkt)) {
3466             /* SSLfatal() already called */
3467             goto err;
3468         }
3469     } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
3470         if (!tls_process_cke_ecdhe(s, pkt)) {
3471             /* SSLfatal() already called */
3472             goto err;
3473         }
3474     } else if (alg_k & SSL_kSRP) {
3475         if (!tls_process_cke_srp(s, pkt)) {
3476             /* SSLfatal() already called */
3477             goto err;
3478         }
3479     } else if (alg_k & SSL_kGOST) {
3480         if (!tls_process_cke_gost(s, pkt)) {
3481             /* SSLfatal() already called */
3482             goto err;
3483         }
3484     } else if (alg_k & SSL_kGOST18) {
3485         if (!tls_process_cke_gost18(s, pkt)) {
3486             /* SSLfatal() already called */
3487             goto err;
3488         }
3489     } else {
3490         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_UNKNOWN_CIPHER_TYPE);
3491         goto err;
3492     }
3493 
3494     return MSG_PROCESS_CONTINUE_PROCESSING;
3495 err:
3496 #ifndef OPENSSL_NO_PSK
3497     OPENSSL_clear_free(s->s3.tmp.psk, s->s3.tmp.psklen);
3498     s->s3.tmp.psk = NULL;
3499     s->s3.tmp.psklen = 0;
3500 #endif
3501     return MSG_PROCESS_ERROR;
3502 }
3503 
tls_post_process_client_key_exchange(SSL_CONNECTION * s,WORK_STATE wst)3504 WORK_STATE tls_post_process_client_key_exchange(SSL_CONNECTION *s,
3505     WORK_STATE wst)
3506 {
3507 #ifndef OPENSSL_NO_SCTP
3508     if (wst == WORK_MORE_A) {
3509         if (SSL_CONNECTION_IS_DTLS(s)) {
3510             unsigned char sctpauthkey[64];
3511             char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
3512             size_t labellen;
3513             /*
3514              * Add new shared key for SCTP-Auth, will be ignored if no SCTP
3515              * used.
3516              */
3517             memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
3518                 sizeof(DTLS1_SCTP_AUTH_LABEL));
3519 
3520             /* Don't include the terminating zero. */
3521             labellen = sizeof(labelbuffer) - 1;
3522             if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
3523                 labellen += 1;
3524 
3525             if (SSL_export_keying_material(SSL_CONNECTION_GET_SSL(s),
3526                     sctpauthkey,
3527                     sizeof(sctpauthkey), labelbuffer,
3528                     labellen, NULL, 0,
3529                     0)
3530                 <= 0) {
3531                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3532                 return WORK_ERROR;
3533             }
3534 
3535             BIO_ctrl(s->wbio, BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
3536                 sizeof(sctpauthkey), sctpauthkey);
3537         }
3538     }
3539 #endif
3540 
3541     if (s->statem.no_cert_verify || !received_client_cert(s)) {
3542         /*
3543          * No certificate verify or no peer certificate so we no longer need
3544          * the handshake_buffer
3545          */
3546         if (!ssl3_digest_cached_records(s, 0)) {
3547             /* SSLfatal() already called */
3548             return WORK_ERROR;
3549         }
3550         return WORK_FINISHED_CONTINUE;
3551     } else {
3552         if (!s->s3.handshake_buffer) {
3553             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3554             return WORK_ERROR;
3555         }
3556         /*
3557          * For sigalgs freeze the handshake buffer. If we support
3558          * extms we've done this already so this is a no-op
3559          */
3560         if (!ssl3_digest_cached_records(s, 1)) {
3561             /* SSLfatal() already called */
3562             return WORK_ERROR;
3563         }
3564     }
3565 
3566     return WORK_FINISHED_CONTINUE;
3567 }
3568 
tls_process_client_rpk(SSL_CONNECTION * sc,PACKET * pkt)3569 MSG_PROCESS_RETURN tls_process_client_rpk(SSL_CONNECTION *sc, PACKET *pkt)
3570 {
3571     MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;
3572     SSL_SESSION *new_sess = NULL;
3573     EVP_PKEY *peer_rpk = NULL;
3574 
3575     if (!tls_process_rpk(sc, pkt, &peer_rpk)) {
3576         /* SSLfatal already called */
3577         goto err;
3578     }
3579 
3580     if (peer_rpk == NULL) {
3581         if ((sc->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)
3582             && (sc->verify_mode & SSL_VERIFY_PEER)) {
3583             SSLfatal(sc, SSL_AD_CERTIFICATE_REQUIRED,
3584                 SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
3585             goto err;
3586         }
3587     } else {
3588         if (ssl_verify_rpk(sc, peer_rpk) <= 0) {
3589             SSLfatal(sc, ssl_x509err2alert(sc->verify_result),
3590                 SSL_R_CERTIFICATE_VERIFY_FAILED);
3591             goto err;
3592         }
3593     }
3594 
3595     /*
3596      * Sessions must be immutable once they go into the session cache. Otherwise
3597      * we can get multi-thread problems. Therefore we don't "update" sessions,
3598      * we replace them with a duplicate. Here, we need to do this every time
3599      * a new RPK (or certificate) is received via post-handshake authentication,
3600      * as the session may have already gone into the session cache.
3601      */
3602 
3603     if (sc->post_handshake_auth == SSL_PHA_REQUESTED) {
3604         if ((new_sess = ssl_session_dup(sc->session, 0)) == NULL) {
3605             SSLfatal(sc, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
3606             goto err;
3607         }
3608 
3609         SSL_SESSION_free(sc->session);
3610         sc->session = new_sess;
3611     }
3612 
3613     /* Ensure there is no peer/peer_chain */
3614     X509_free(sc->session->peer);
3615     sc->session->peer = NULL;
3616     sk_X509_pop_free(sc->session->peer_chain, X509_free);
3617     sc->session->peer_chain = NULL;
3618     /* Save RPK */
3619     EVP_PKEY_free(sc->session->peer_rpk);
3620     sc->session->peer_rpk = peer_rpk;
3621     peer_rpk = NULL;
3622 
3623     sc->session->verify_result = sc->verify_result;
3624 
3625     /*
3626      * Freeze the handshake buffer. For <TLS1.3 we do this after the CKE
3627      * message
3628      */
3629     if (SSL_CONNECTION_IS_TLS13(sc)) {
3630         if (!ssl3_digest_cached_records(sc, 1)) {
3631             /* SSLfatal() already called */
3632             goto err;
3633         }
3634 
3635         /* Save the current hash state for when we receive the CertificateVerify */
3636         if (!ssl_handshake_hash(sc, sc->cert_verify_hash,
3637                 sizeof(sc->cert_verify_hash),
3638                 &sc->cert_verify_hash_len)) {
3639             /* SSLfatal() already called */;
3640             goto err;
3641         }
3642 
3643         /* resend session tickets */
3644         sc->sent_tickets = 0;
3645     }
3646 
3647     ret = MSG_PROCESS_CONTINUE_READING;
3648 
3649 err:
3650     EVP_PKEY_free(peer_rpk);
3651     return ret;
3652 }
3653 
tls_process_client_certificate(SSL_CONNECTION * s,PACKET * pkt)3654 MSG_PROCESS_RETURN tls_process_client_certificate(SSL_CONNECTION *s,
3655     PACKET *pkt)
3656 {
3657     int i;
3658     MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;
3659     X509 *x = NULL;
3660     unsigned long l;
3661     const unsigned char *certstart, *certbytes;
3662     STACK_OF(X509) *sk = NULL;
3663     PACKET spkt, context;
3664     size_t chainidx;
3665     SSL_SESSION *new_sess = NULL;
3666     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
3667 
3668     /*
3669      * To get this far we must have read encrypted data from the client. We no
3670      * longer tolerate unencrypted alerts. This is ignored if less than TLSv1.3
3671      */
3672     if (s->rlayer.rrlmethod->set_plain_alerts != NULL)
3673         s->rlayer.rrlmethod->set_plain_alerts(s->rlayer.rrl, 0);
3674 
3675     if (s->ext.client_cert_type == TLSEXT_cert_type_rpk)
3676         return tls_process_client_rpk(s, pkt);
3677 
3678     if (s->ext.client_cert_type != TLSEXT_cert_type_x509) {
3679         SSLfatal(s, SSL_AD_UNSUPPORTED_CERTIFICATE,
3680             SSL_R_UNKNOWN_CERTIFICATE_TYPE);
3681         goto err;
3682     }
3683 
3684     if ((sk = sk_X509_new_null()) == NULL) {
3685         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
3686         goto err;
3687     }
3688 
3689     if (SSL_CONNECTION_IS_TLS13(s)
3690         && (!PACKET_get_length_prefixed_1(pkt, &context)
3691             || (s->pha_context == NULL && PACKET_remaining(&context) != 0)
3692             || (s->pha_context != NULL
3693                 && !PACKET_equal(&context, s->pha_context,
3694                     s->pha_context_len)))) {
3695         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_INVALID_CONTEXT);
3696         goto err;
3697     }
3698 
3699     if (!PACKET_get_length_prefixed_3(pkt, &spkt)
3700         || PACKET_remaining(pkt) != 0) {
3701         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
3702         goto err;
3703     }
3704 
3705     for (chainidx = 0; PACKET_remaining(&spkt) > 0; chainidx++) {
3706         if (!PACKET_get_net_3(&spkt, &l)
3707             || !PACKET_get_bytes(&spkt, &certbytes, l)) {
3708             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_CERT_LENGTH_MISMATCH);
3709             goto err;
3710         }
3711 
3712         certstart = certbytes;
3713         x = X509_new_ex(sctx->libctx, sctx->propq);
3714         if (x == NULL) {
3715             SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_X509_LIB);
3716             goto err;
3717         }
3718         if (d2i_X509(&x, (const unsigned char **)&certbytes, l) == NULL) {
3719             SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_ASN1_LIB);
3720             goto err;
3721         }
3722 
3723         if (certbytes != (certstart + l)) {
3724             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_CERT_LENGTH_MISMATCH);
3725             goto err;
3726         }
3727 
3728         if (SSL_CONNECTION_IS_TLS13(s)) {
3729             RAW_EXTENSION *rawexts = NULL;
3730             PACKET extensions;
3731 
3732             if (!PACKET_get_length_prefixed_2(&spkt, &extensions)) {
3733                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
3734                 goto err;
3735             }
3736             if (!tls_collect_extensions(s, &extensions,
3737                     SSL_EXT_TLS1_3_CERTIFICATE, &rawexts,
3738                     NULL, chainidx == 0)
3739                 || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE,
3740                     rawexts, x, chainidx,
3741                     PACKET_remaining(&spkt) == 0)) {
3742                 OPENSSL_free(rawexts);
3743                 goto err;
3744             }
3745             OPENSSL_free(rawexts);
3746         }
3747 
3748         if (!sk_X509_push(sk, x)) {
3749             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
3750             goto err;
3751         }
3752         x = NULL;
3753     }
3754 
3755     if (sk_X509_num(sk) <= 0) {
3756         /* TLS does not mind 0 certs returned */
3757         if (s->version == SSL3_VERSION) {
3758             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3759                 SSL_R_NO_CERTIFICATES_RETURNED);
3760             goto err;
3761         }
3762         /* Fail for TLS only if we required a certificate */
3763         else if ((s->verify_mode & SSL_VERIFY_PEER) && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) {
3764             SSLfatal(s, SSL_AD_CERTIFICATE_REQUIRED,
3765                 SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
3766             goto err;
3767         }
3768         /* No client certificate so digest cached records */
3769         if (s->s3.handshake_buffer && !ssl3_digest_cached_records(s, 0)) {
3770             /* SSLfatal() already called */
3771             goto err;
3772         }
3773     } else {
3774         EVP_PKEY *pkey;
3775         i = ssl_verify_cert_chain(s, sk);
3776         if (i <= 0) {
3777             SSLfatal(s, ssl_x509err2alert(s->verify_result),
3778                 SSL_R_CERTIFICATE_VERIFY_FAILED);
3779             goto err;
3780         }
3781         pkey = X509_get0_pubkey(sk_X509_value(sk, 0));
3782         if (pkey == NULL) {
3783             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3784                 SSL_R_UNKNOWN_CERTIFICATE_TYPE);
3785             goto err;
3786         }
3787     }
3788 
3789     /*
3790      * Sessions must be immutable once they go into the session cache. Otherwise
3791      * we can get multi-thread problems. Therefore we don't "update" sessions,
3792      * we replace them with a duplicate. Here, we need to do this every time
3793      * a new certificate is received via post-handshake authentication, as the
3794      * session may have already gone into the session cache.
3795      */
3796 
3797     if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
3798         if ((new_sess = ssl_session_dup(s->session, 0)) == 0) {
3799             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SSL_LIB);
3800             goto err;
3801         }
3802 
3803         SSL_SESSION_free(s->session);
3804         s->session = new_sess;
3805     }
3806 
3807     X509_free(s->session->peer);
3808     s->session->peer = sk_X509_shift(sk);
3809     s->session->verify_result = s->verify_result;
3810 
3811     OSSL_STACK_OF_X509_free(s->session->peer_chain);
3812     s->session->peer_chain = sk;
3813     sk = NULL;
3814     /* Ensure there is no RPK */
3815     EVP_PKEY_free(s->session->peer_rpk);
3816     s->session->peer_rpk = NULL;
3817 
3818     /*
3819      * Freeze the handshake buffer. For <TLS1.3 we do this after the CKE
3820      * message
3821      */
3822     if (SSL_CONNECTION_IS_TLS13(s) && !ssl3_digest_cached_records(s, 1)) {
3823         /* SSLfatal() already called */
3824         goto err;
3825     }
3826 
3827     /*
3828      * Inconsistency alert: cert_chain does *not* include the peer's own
3829      * certificate, while we do include it in statem_clnt.c
3830      */
3831 
3832     /* Save the current hash state for when we receive the CertificateVerify */
3833     if (SSL_CONNECTION_IS_TLS13(s)) {
3834         if (!ssl_handshake_hash(s, s->cert_verify_hash,
3835                 sizeof(s->cert_verify_hash),
3836                 &s->cert_verify_hash_len)) {
3837             /* SSLfatal() already called */
3838             goto err;
3839         }
3840 
3841         /* Resend session tickets */
3842         s->sent_tickets = 0;
3843     }
3844 
3845     ret = MSG_PROCESS_CONTINUE_READING;
3846 
3847 err:
3848     X509_free(x);
3849     OSSL_STACK_OF_X509_free(sk);
3850     return ret;
3851 }
3852 
3853 #ifndef OPENSSL_NO_COMP_ALG
tls_process_client_compressed_certificate(SSL_CONNECTION * sc,PACKET * pkt)3854 MSG_PROCESS_RETURN tls_process_client_compressed_certificate(SSL_CONNECTION *sc, PACKET *pkt)
3855 {
3856     MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;
3857     PACKET tmppkt;
3858     BUF_MEM *buf = BUF_MEM_new();
3859 
3860     if (tls13_process_compressed_certificate(sc, pkt, &tmppkt, buf) != MSG_PROCESS_ERROR)
3861         ret = tls_process_client_certificate(sc, &tmppkt);
3862 
3863     BUF_MEM_free(buf);
3864     return ret;
3865 }
3866 #endif
3867 
tls_construct_server_certificate(SSL_CONNECTION * s,WPACKET * pkt)3868 CON_FUNC_RETURN tls_construct_server_certificate(SSL_CONNECTION *s, WPACKET *pkt)
3869 {
3870     CERT_PKEY *cpk = s->s3.tmp.cert;
3871 
3872     if (cpk == NULL) {
3873         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3874         return CON_FUNC_ERROR;
3875     }
3876 
3877     /*
3878      * In TLSv1.3 the certificate chain is always preceded by a 0 length context
3879      * for the server Certificate message
3880      */
3881     if (SSL_CONNECTION_IS_TLS13(s) && !WPACKET_put_bytes_u8(pkt, 0)) {
3882         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3883         return CON_FUNC_ERROR;
3884     }
3885     switch (s->ext.server_cert_type) {
3886     case TLSEXT_cert_type_rpk:
3887         if (!tls_output_rpk(s, pkt, cpk)) {
3888             /* SSLfatal() already called */
3889             return 0;
3890         }
3891         break;
3892     case TLSEXT_cert_type_x509:
3893         if (!ssl3_output_cert_chain(s, pkt, cpk, 0)) {
3894             /* SSLfatal() already called */
3895             return 0;
3896         }
3897         break;
3898     default:
3899         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3900         return 0;
3901     }
3902 
3903     return CON_FUNC_SUCCESS;
3904 }
3905 
3906 #ifndef OPENSSL_NO_COMP_ALG
tls_construct_server_compressed_certificate(SSL_CONNECTION * sc,WPACKET * pkt)3907 CON_FUNC_RETURN tls_construct_server_compressed_certificate(SSL_CONNECTION *sc, WPACKET *pkt)
3908 {
3909     int alg = get_compressed_certificate_alg(sc);
3910     OSSL_COMP_CERT *cc = sc->s3.tmp.cert->comp_cert[alg];
3911 
3912     if (!ossl_assert(cc != NULL)) {
3913         SSLfatal(sc, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3914         return 0;
3915     }
3916     /*
3917      * Server can't compress on-demand
3918      * Use pre-compressed certificate
3919      */
3920     if (!WPACKET_put_bytes_u16(pkt, alg)
3921         || !WPACKET_put_bytes_u24(pkt, cc->orig_len)
3922         || !WPACKET_start_sub_packet_u24(pkt)
3923         || !WPACKET_memcpy(pkt, cc->data, cc->len)
3924         || !WPACKET_close(pkt))
3925         return 0;
3926 
3927     sc->s3.tmp.cert->cert_comp_used++;
3928     return 1;
3929 }
3930 #endif
3931 
create_ticket_prequel(SSL_CONNECTION * s,WPACKET * pkt,uint32_t age_add,unsigned char * tick_nonce)3932 static int create_ticket_prequel(SSL_CONNECTION *s, WPACKET *pkt,
3933     uint32_t age_add, unsigned char *tick_nonce)
3934 {
3935     uint32_t timeout = (uint32_t)ossl_time2seconds(s->session->timeout);
3936 
3937     /*
3938      * Ticket lifetime hint:
3939      * In TLSv1.3 we reset the "time" field above, and always specify the
3940      * timeout, limited to a 1 week period per RFC8446.
3941      * For TLSv1.2 this is advisory only and we leave this unspecified for
3942      * resumed session (for simplicity).
3943      */
3944 #define ONE_WEEK_SEC (7 * 24 * 60 * 60)
3945 
3946     if (SSL_CONNECTION_IS_TLS13(s)) {
3947         if (ossl_time_compare(s->session->timeout,
3948                 ossl_seconds2time(ONE_WEEK_SEC))
3949             > 0)
3950             timeout = ONE_WEEK_SEC;
3951     } else if (s->hit)
3952         timeout = 0;
3953 
3954     if (!WPACKET_put_bytes_u32(pkt, timeout)) {
3955         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3956         return 0;
3957     }
3958 
3959     if (SSL_CONNECTION_IS_TLS13(s)) {
3960         if (!WPACKET_put_bytes_u32(pkt, age_add)
3961             || !WPACKET_sub_memcpy_u8(pkt, tick_nonce, TICKET_NONCE_SIZE)) {
3962             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3963             return 0;
3964         }
3965     }
3966 
3967     /* Start the sub-packet for the actual ticket data */
3968     if (!WPACKET_start_sub_packet_u16(pkt)) {
3969         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
3970         return 0;
3971     }
3972 
3973     return 1;
3974 }
3975 
construct_stateless_ticket(SSL_CONNECTION * s,WPACKET * pkt,uint32_t age_add,unsigned char * tick_nonce)3976 static CON_FUNC_RETURN construct_stateless_ticket(SSL_CONNECTION *s,
3977     WPACKET *pkt,
3978     uint32_t age_add,
3979     unsigned char *tick_nonce)
3980 {
3981     unsigned char *senc = NULL;
3982     EVP_CIPHER_CTX *ctx = NULL;
3983     SSL_HMAC *hctx = NULL;
3984     unsigned char *p, *encdata1, *encdata2, *macdata1, *macdata2;
3985     const unsigned char *const_p;
3986     int len, slen_full, slen, lenfinal;
3987     SSL_SESSION *sess;
3988     size_t hlen;
3989     SSL_CTX *tctx = s->session_ctx;
3990     unsigned char iv[EVP_MAX_IV_LENGTH];
3991     unsigned char key_name[TLSEXT_KEYNAME_LENGTH];
3992     int iv_len;
3993     CON_FUNC_RETURN ok = CON_FUNC_ERROR;
3994     size_t macoffset, macendoffset;
3995     SSL *ssl = SSL_CONNECTION_GET_USER_SSL(s);
3996     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
3997 
3998     /* get session encoding length */
3999     slen_full = i2d_SSL_SESSION(s->session, NULL);
4000     /*
4001      * Some length values are 16 bits, so forget it if session is too
4002      * long
4003      */
4004     if (slen_full == 0 || slen_full > 0xFF00) {
4005         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4006         goto err;
4007     }
4008     senc = OPENSSL_malloc(slen_full);
4009     if (senc == NULL) {
4010         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
4011         goto err;
4012     }
4013 
4014     ctx = EVP_CIPHER_CTX_new();
4015     if (ctx == NULL) {
4016         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
4017         goto err;
4018     }
4019     hctx = ssl_hmac_new(tctx);
4020     if (hctx == NULL) {
4021         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SSL_LIB);
4022         goto err;
4023     }
4024 
4025     p = senc;
4026     if (!i2d_SSL_SESSION(s->session, &p)) {
4027         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4028         goto err;
4029     }
4030 
4031     /*
4032      * create a fresh copy (not shared with other threads) to clean up
4033      */
4034     const_p = senc;
4035     sess = d2i_SSL_SESSION_ex(NULL, &const_p, slen_full, sctx->libctx,
4036         sctx->propq);
4037     if (sess == NULL) {
4038         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4039         goto err;
4040     }
4041 
4042     slen = i2d_SSL_SESSION(sess, NULL);
4043     if (slen == 0 || slen > slen_full) {
4044         /* shouldn't ever happen */
4045         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4046         SSL_SESSION_free(sess);
4047         goto err;
4048     }
4049     p = senc;
4050     if (!i2d_SSL_SESSION(sess, &p)) {
4051         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4052         SSL_SESSION_free(sess);
4053         goto err;
4054     }
4055     SSL_SESSION_free(sess);
4056 
4057     /*
4058      * Initialize HMAC and cipher contexts. If callback present it does
4059      * all the work otherwise use generated values from parent ctx.
4060      */
4061 #ifndef OPENSSL_NO_DEPRECATED_3_0
4062     if (tctx->ext.ticket_key_evp_cb != NULL || tctx->ext.ticket_key_cb != NULL)
4063 #else
4064     if (tctx->ext.ticket_key_evp_cb != NULL)
4065 #endif
4066     {
4067         int ret = 0;
4068 
4069         if (tctx->ext.ticket_key_evp_cb != NULL)
4070             ret = tctx->ext.ticket_key_evp_cb(ssl, key_name, iv, ctx,
4071                 ssl_hmac_get0_EVP_MAC_CTX(hctx),
4072                 1);
4073 #ifndef OPENSSL_NO_DEPRECATED_3_0
4074         else if (tctx->ext.ticket_key_cb != NULL)
4075             /* if 0 is returned, write an empty ticket */
4076             ret = tctx->ext.ticket_key_cb(ssl, key_name, iv, ctx,
4077                 ssl_hmac_get0_HMAC_CTX(hctx), 1);
4078 #endif
4079 
4080         if (ret == 0) {
4081             /*
4082              * In TLSv1.2 we construct a 0 length ticket. In TLSv1.3 a 0
4083              * length ticket is not allowed so we abort construction of the
4084              * ticket
4085              */
4086             if (SSL_CONNECTION_IS_TLS13(s)) {
4087                 ok = CON_FUNC_DONT_SEND;
4088                 goto err;
4089             }
4090             /* Put timeout and length */
4091             if (!WPACKET_put_bytes_u32(pkt, 0)
4092                 || !WPACKET_put_bytes_u16(pkt, 0)) {
4093                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4094                 goto err;
4095             }
4096             OPENSSL_free(senc);
4097             EVP_CIPHER_CTX_free(ctx);
4098             ssl_hmac_free(hctx);
4099             return CON_FUNC_SUCCESS;
4100         }
4101         if (ret < 0) {
4102             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_CALLBACK_FAILED);
4103             goto err;
4104         }
4105         iv_len = EVP_CIPHER_CTX_get_iv_length(ctx);
4106         if (iv_len < 0) {
4107             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4108             goto err;
4109         }
4110     } else {
4111         EVP_CIPHER *cipher = EVP_CIPHER_fetch(sctx->libctx, "AES-256-CBC",
4112             sctx->propq);
4113 
4114         if (cipher == NULL) {
4115             /* Error is already recorded */
4116             SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
4117             goto err;
4118         }
4119 
4120         iv_len = EVP_CIPHER_get_iv_length(cipher);
4121         if (iv_len < 0
4122             || RAND_bytes_ex(sctx->libctx, iv, iv_len, 0) <= 0
4123             || !EVP_EncryptInit_ex(ctx, cipher, NULL,
4124                 tctx->ext.secure->tick_aes_key, iv)
4125             || !ssl_hmac_init(hctx, tctx->ext.secure->tick_hmac_key,
4126                 sizeof(tctx->ext.secure->tick_hmac_key),
4127                 "SHA256")) {
4128             EVP_CIPHER_free(cipher);
4129             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4130             goto err;
4131         }
4132         EVP_CIPHER_free(cipher);
4133         memcpy(key_name, tctx->ext.tick_key_name,
4134             sizeof(tctx->ext.tick_key_name));
4135     }
4136 
4137     if (!create_ticket_prequel(s, pkt, age_add, tick_nonce)) {
4138         /* SSLfatal() already called */
4139         goto err;
4140     }
4141 
4142     if (!WPACKET_get_total_written(pkt, &macoffset)
4143         /* Output key name */
4144         || !WPACKET_memcpy(pkt, key_name, sizeof(key_name))
4145         /* output IV */
4146         || !WPACKET_memcpy(pkt, iv, iv_len)
4147         || !WPACKET_reserve_bytes(pkt, slen + EVP_MAX_BLOCK_LENGTH,
4148             &encdata1)
4149         /* Encrypt session data */
4150         || !EVP_EncryptUpdate(ctx, encdata1, &len, senc, slen)
4151         || !WPACKET_allocate_bytes(pkt, len, &encdata2)
4152         || encdata1 != encdata2
4153         || !EVP_EncryptFinal(ctx, encdata1 + len, &lenfinal)
4154         || !WPACKET_allocate_bytes(pkt, lenfinal, &encdata2)
4155         || encdata1 + len != encdata2
4156         || len + lenfinal > slen + EVP_MAX_BLOCK_LENGTH
4157         || !WPACKET_get_total_written(pkt, &macendoffset)
4158         || !ssl_hmac_update(hctx,
4159             (unsigned char *)s->init_buf->data + macoffset,
4160             macendoffset - macoffset)
4161         || !WPACKET_reserve_bytes(pkt, EVP_MAX_MD_SIZE, &macdata1)
4162         || !ssl_hmac_final(hctx, macdata1, &hlen, EVP_MAX_MD_SIZE)
4163         || hlen > EVP_MAX_MD_SIZE
4164         || !WPACKET_allocate_bytes(pkt, hlen, &macdata2)
4165         || macdata1 != macdata2) {
4166         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4167         goto err;
4168     }
4169 
4170     /* Close the sub-packet created by create_ticket_prequel() */
4171     if (!WPACKET_close(pkt)) {
4172         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4173         goto err;
4174     }
4175 
4176     ok = CON_FUNC_SUCCESS;
4177 err:
4178     OPENSSL_free(senc);
4179     EVP_CIPHER_CTX_free(ctx);
4180     ssl_hmac_free(hctx);
4181     return ok;
4182 }
4183 
construct_stateful_ticket(SSL_CONNECTION * s,WPACKET * pkt,uint32_t age_add,unsigned char * tick_nonce)4184 static int construct_stateful_ticket(SSL_CONNECTION *s, WPACKET *pkt,
4185     uint32_t age_add,
4186     unsigned char *tick_nonce)
4187 {
4188     if (!create_ticket_prequel(s, pkt, age_add, tick_nonce)) {
4189         /* SSLfatal() already called */
4190         return 0;
4191     }
4192 
4193     if (!WPACKET_memcpy(pkt, s->session->session_id,
4194             s->session->session_id_length)
4195         || !WPACKET_close(pkt)) {
4196         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4197         return 0;
4198     }
4199 
4200     return 1;
4201 }
4202 
tls_update_ticket_counts(SSL_CONNECTION * s)4203 static void tls_update_ticket_counts(SSL_CONNECTION *s)
4204 {
4205     /*
4206      * Increment both |sent_tickets| and |next_ticket_nonce|. |sent_tickets|
4207      * gets reset to 0 if we send more tickets following a post-handshake
4208      * auth, but |next_ticket_nonce| does not.  If we're sending extra
4209      * tickets, decrement the count of pending extra tickets.
4210      */
4211     s->sent_tickets++;
4212     s->next_ticket_nonce++;
4213     if (s->ext.extra_tickets_expected > 0)
4214         s->ext.extra_tickets_expected--;
4215 }
4216 
tls_construct_new_session_ticket(SSL_CONNECTION * s,WPACKET * pkt)4217 CON_FUNC_RETURN tls_construct_new_session_ticket(SSL_CONNECTION *s, WPACKET *pkt)
4218 {
4219     SSL_CTX *tctx = s->session_ctx;
4220     unsigned char tick_nonce[TICKET_NONCE_SIZE];
4221     union {
4222         unsigned char age_add_c[sizeof(uint32_t)];
4223         uint32_t age_add;
4224     } age_add_u;
4225     CON_FUNC_RETURN ret = CON_FUNC_ERROR;
4226 
4227     age_add_u.age_add = 0;
4228 
4229     if (SSL_CONNECTION_IS_TLS13(s)) {
4230         size_t i, hashlen;
4231         uint64_t nonce;
4232         /* ASCII: "resumption", in hex for EBCDIC compatibility */
4233         static const unsigned char nonce_label[] = { 0x72, 0x65, 0x73, 0x75, 0x6D,
4234             0x70, 0x74, 0x69, 0x6F, 0x6E };
4235         const EVP_MD *md = ssl_handshake_md(s);
4236         int hashleni = EVP_MD_get_size(md);
4237 
4238         /* Ensure cast to size_t is safe */
4239         if (!ossl_assert(hashleni > 0)) {
4240             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4241             goto err;
4242         }
4243         hashlen = (size_t)hashleni;
4244 
4245         /*
4246          * If we already sent one NewSessionTicket, or we resumed then
4247          * s->session may already be in a cache and so we must not modify it.
4248          * Instead we need to take a copy of it and modify that.
4249          */
4250         if (s->sent_tickets != 0 || s->hit) {
4251             SSL_SESSION *new_sess = ssl_session_dup(s->session, 0);
4252 
4253             if (new_sess == NULL) {
4254                 /* SSLfatal already called */
4255                 goto err;
4256             }
4257 
4258             SSL_SESSION_free(s->session);
4259             s->session = new_sess;
4260         }
4261 
4262         if (!ssl_generate_session_id(s, s->session)) {
4263             /* SSLfatal() already called */
4264             goto err;
4265         }
4266         if (RAND_bytes_ex(SSL_CONNECTION_GET_CTX(s)->libctx,
4267                 age_add_u.age_add_c, sizeof(age_add_u), 0)
4268             <= 0) {
4269             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4270             goto err;
4271         }
4272         s->session->ext.tick_age_add = age_add_u.age_add;
4273 
4274         nonce = s->next_ticket_nonce;
4275         for (i = TICKET_NONCE_SIZE; i > 0; i--) {
4276             tick_nonce[i - 1] = (unsigned char)(nonce & 0xff);
4277             nonce >>= 8;
4278         }
4279 
4280         if (!tls13_hkdf_expand(s, md, s->resumption_master_secret,
4281                 nonce_label,
4282                 sizeof(nonce_label),
4283                 tick_nonce,
4284                 TICKET_NONCE_SIZE,
4285                 s->session->master_key,
4286                 hashlen, 1)) {
4287             /* SSLfatal() already called */
4288             goto err;
4289         }
4290         s->session->master_key_length = hashlen;
4291 
4292         s->session->time = ossl_time_now();
4293         ssl_session_calculate_timeout(s->session);
4294         if (s->s3.alpn_selected != NULL) {
4295             OPENSSL_free(s->session->ext.alpn_selected);
4296             s->session->ext.alpn_selected = OPENSSL_memdup(s->s3.alpn_selected, s->s3.alpn_selected_len);
4297             if (s->session->ext.alpn_selected == NULL) {
4298                 s->session->ext.alpn_selected_len = 0;
4299                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
4300                 goto err;
4301             }
4302             s->session->ext.alpn_selected_len = s->s3.alpn_selected_len;
4303         }
4304         s->session->ext.max_early_data = s->max_early_data;
4305     }
4306 
4307     if (tctx->generate_ticket_cb != NULL && tctx->generate_ticket_cb(SSL_CONNECTION_GET_USER_SSL(s), tctx->ticket_cb_data) == 0) {
4308         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4309         goto err;
4310     }
4311     /*
4312      * If we are using anti-replay protection then we behave as if
4313      * SSL_OP_NO_TICKET is set - we are caching tickets anyway so there
4314      * is no point in using full stateless tickets.
4315      */
4316     if (SSL_CONNECTION_IS_TLS13(s)
4317         && ((s->options & SSL_OP_NO_TICKET) != 0
4318             || (s->max_early_data > 0
4319                 && (s->options & SSL_OP_NO_ANTI_REPLAY) == 0))) {
4320         if (!construct_stateful_ticket(s, pkt, age_add_u.age_add, tick_nonce)) {
4321             /* SSLfatal() already called */
4322             goto err;
4323         }
4324     } else {
4325         CON_FUNC_RETURN tmpret;
4326 
4327         tmpret = construct_stateless_ticket(s, pkt, age_add_u.age_add,
4328             tick_nonce);
4329         if (tmpret != CON_FUNC_SUCCESS) {
4330             if (tmpret == CON_FUNC_DONT_SEND) {
4331                 /* Non-fatal. Abort construction but continue */
4332                 ret = CON_FUNC_DONT_SEND;
4333                 /* We count this as a success so update the counts anwyay */
4334                 tls_update_ticket_counts(s);
4335             }
4336             /* else SSLfatal() already called */
4337             goto err;
4338         }
4339     }
4340 
4341     if (SSL_CONNECTION_IS_TLS13(s)) {
4342         if (!tls_construct_extensions(s, pkt,
4343                 SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
4344                 NULL, 0)) {
4345             /* SSLfatal() already called */
4346             goto err;
4347         }
4348         tls_update_ticket_counts(s);
4349         ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
4350     }
4351 
4352     ret = CON_FUNC_SUCCESS;
4353 err:
4354     return ret;
4355 }
4356 
4357 /*
4358  * In TLSv1.3 this is called from the extensions code, otherwise it is used to
4359  * create a separate message. Returns 1 on success or 0 on failure.
4360  */
tls_construct_cert_status_body(SSL_CONNECTION * s,WPACKET * pkt)4361 int tls_construct_cert_status_body(SSL_CONNECTION *s, WPACKET *pkt)
4362 {
4363     if (!WPACKET_put_bytes_u8(pkt, s->ext.status_type)
4364         || !WPACKET_sub_memcpy_u24(pkt, s->ext.ocsp.resp,
4365             s->ext.ocsp.resp_len)) {
4366         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4367         return 0;
4368     }
4369 
4370     return 1;
4371 }
4372 
tls_construct_cert_status(SSL_CONNECTION * s,WPACKET * pkt)4373 CON_FUNC_RETURN tls_construct_cert_status(SSL_CONNECTION *s, WPACKET *pkt)
4374 {
4375     if (!tls_construct_cert_status_body(s, pkt)) {
4376         /* SSLfatal() already called */
4377         return CON_FUNC_ERROR;
4378     }
4379 
4380     return CON_FUNC_SUCCESS;
4381 }
4382 
4383 #ifndef OPENSSL_NO_NEXTPROTONEG
4384 /*
4385  * tls_process_next_proto reads a Next Protocol Negotiation handshake message.
4386  * It sets the next_proto member in s if found
4387  */
tls_process_next_proto(SSL_CONNECTION * s,PACKET * pkt)4388 MSG_PROCESS_RETURN tls_process_next_proto(SSL_CONNECTION *s, PACKET *pkt)
4389 {
4390     PACKET next_proto, padding;
4391     size_t next_proto_len;
4392 
4393     /*-
4394      * The payload looks like:
4395      *   uint8 proto_len;
4396      *   uint8 proto[proto_len];
4397      *   uint8 padding_len;
4398      *   uint8 padding[padding_len];
4399      */
4400     if (!PACKET_get_length_prefixed_1(pkt, &next_proto)
4401         || !PACKET_get_length_prefixed_1(pkt, &padding)
4402         || PACKET_remaining(pkt) > 0) {
4403         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
4404         return MSG_PROCESS_ERROR;
4405     }
4406 
4407     if (!PACKET_memdup(&next_proto, &s->ext.npn, &next_proto_len)) {
4408         s->ext.npn_len = 0;
4409         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4410         return MSG_PROCESS_ERROR;
4411     }
4412 
4413     s->ext.npn_len = (unsigned char)next_proto_len;
4414 
4415     return MSG_PROCESS_CONTINUE_READING;
4416 }
4417 #endif
4418 
tls_construct_encrypted_extensions(SSL_CONNECTION * s,WPACKET * pkt)4419 static CON_FUNC_RETURN tls_construct_encrypted_extensions(SSL_CONNECTION *s,
4420     WPACKET *pkt)
4421 {
4422     if (!tls_construct_extensions(s, pkt, SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
4423             NULL, 0)) {
4424         /* SSLfatal() already called */
4425         return CON_FUNC_ERROR;
4426     }
4427 
4428     return CON_FUNC_SUCCESS;
4429 }
4430 
tls_process_end_of_early_data(SSL_CONNECTION * s,PACKET * pkt)4431 MSG_PROCESS_RETURN tls_process_end_of_early_data(SSL_CONNECTION *s, PACKET *pkt)
4432 {
4433     if (PACKET_remaining(pkt) != 0) {
4434         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
4435         return MSG_PROCESS_ERROR;
4436     }
4437 
4438     if (s->early_data_state != SSL_EARLY_DATA_READING
4439         && s->early_data_state != SSL_EARLY_DATA_READ_RETRY) {
4440         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
4441         return MSG_PROCESS_ERROR;
4442     }
4443 
4444     /*
4445      * EndOfEarlyData signals a key change so the end of the message must be on
4446      * a record boundary.
4447      */
4448     if (RECORD_LAYER_processed_read_pending(&s->rlayer)) {
4449         SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_NOT_ON_RECORD_BOUNDARY);
4450         return MSG_PROCESS_ERROR;
4451     }
4452 
4453     s->early_data_state = SSL_EARLY_DATA_FINISHED_READING;
4454     if (!SSL_CONNECTION_GET_SSL(s)->method->ssl3_enc->change_cipher_state(s,
4455             SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_READ)) {
4456         /* SSLfatal() already called */
4457         return MSG_PROCESS_ERROR;
4458     }
4459 
4460     return MSG_PROCESS_CONTINUE_READING;
4461 }
4462