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      1 /*
      2  * Copyright 1995-2025 The OpenSSL Project Authors. All Rights Reserved.
      3  * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
      4  * Copyright 2005 Nokia. All rights reserved.
      5  *
      6  * Licensed under the Apache License 2.0 (the "License").  You may not use
      7  * this file except in compliance with the License.  You can obtain a copy
      8  * in the file LICENSE in the source distribution or at
      9  * https://www.openssl.org/source/license.html
     10  */
     11 
     12 #include <stdio.h>
     13 #include <time.h>
     14 #include <assert.h>
     15 #include "../ssl_local.h"
     16 #include "statem_local.h"
     17 #include <openssl/buffer.h>
     18 #include <openssl/rand.h>
     19 #include <openssl/objects.h>
     20 #include <openssl/evp.h>
     21 #include <openssl/md5.h>
     22 #include <openssl/dh.h>
     23 #include <openssl/rsa.h>
     24 #include <openssl/bn.h>
     25 #include <openssl/engine.h>
     26 #include <openssl/trace.h>
     27 #include <openssl/core_names.h>
     28 #include <openssl/param_build.h>
     29 #include "internal/cryptlib.h"
     30 #include "internal/comp.h"
     31 #include "internal/ssl_unwrap.h"
     32 
     33 static MSG_PROCESS_RETURN tls_process_as_hello_retry_request(SSL_CONNECTION *s,
     34     PACKET *pkt);
     35 static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL_CONNECTION *s,
     36     PACKET *pkt);
     37 
     38 static ossl_inline int cert_req_allowed(SSL_CONNECTION *s);
     39 static int key_exchange_expected(SSL_CONNECTION *s);
     40 static int ssl_cipher_list_to_bytes(SSL_CONNECTION *s, STACK_OF(SSL_CIPHER) *sk,
     41     WPACKET *pkt);
     42 
     43 static ossl_inline int received_server_cert(SSL_CONNECTION *sc)
     44 {
     45     return sc->session->peer_rpk != NULL || sc->session->peer != NULL;
     46 }
     47 
     48 /*
     49  * Is a CertificateRequest message allowed at the moment or not?
     50  *
     51  *  Return values are:
     52  *  1: Yes
     53  *  0: No
     54  */
     55 static ossl_inline int cert_req_allowed(SSL_CONNECTION *s)
     56 {
     57     /* TLS does not like anon-DH with client cert */
     58     if ((s->version > SSL3_VERSION
     59             && (s->s3.tmp.new_cipher->algorithm_auth & SSL_aNULL))
     60         || (s->s3.tmp.new_cipher->algorithm_auth & (SSL_aSRP | SSL_aPSK)))
     61         return 0;
     62 
     63     return 1;
     64 }
     65 
     66 /*
     67  * Should we expect the ServerKeyExchange message or not?
     68  *
     69  *  Return values are:
     70  *  1: Yes
     71  *  0: No
     72  */
     73 static int key_exchange_expected(SSL_CONNECTION *s)
     74 {
     75     long alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
     76 
     77     /*
     78      * Can't skip server key exchange if this is an ephemeral
     79      * ciphersuite or for SRP
     80      */
     81     if (alg_k & (SSL_kDHE | SSL_kECDHE | SSL_kDHEPSK | SSL_kECDHEPSK | SSL_kSRP)) {
     82         return 1;
     83     }
     84 
     85     return 0;
     86 }
     87 
     88 /*
     89  * ossl_statem_client_read_transition() encapsulates the logic for the allowed
     90  * handshake state transitions when a TLS1.3 client is reading messages from the
     91  * server. The message type that the server has sent is provided in |mt|. The
     92  * current state is in |s->statem.hand_state|.
     93  *
     94  * Return values are 1 for success (transition allowed) and  0 on error
     95  * (transition not allowed)
     96  */
     97 static int ossl_statem_client13_read_transition(SSL_CONNECTION *s, int mt)
     98 {
     99     OSSL_STATEM *st = &s->statem;
    100 
    101     /*
    102      * Note: There is no case for TLS_ST_CW_CLNT_HELLO, because we haven't
    103      * yet negotiated TLSv1.3 at that point so that is handled by
    104      * ossl_statem_client_read_transition()
    105      */
    106 
    107     switch (st->hand_state) {
    108     default:
    109         break;
    110 
    111     case TLS_ST_CW_CLNT_HELLO:
    112         /*
    113          * This must a ClientHello following a HelloRetryRequest, so the only
    114          * thing we can get now is a ServerHello.
    115          */
    116         if (mt == SSL3_MT_SERVER_HELLO) {
    117             st->hand_state = TLS_ST_CR_SRVR_HELLO;
    118             return 1;
    119         }
    120         break;
    121 
    122     case TLS_ST_CR_SRVR_HELLO:
    123         if (mt == SSL3_MT_ENCRYPTED_EXTENSIONS) {
    124             st->hand_state = TLS_ST_CR_ENCRYPTED_EXTENSIONS;
    125             return 1;
    126         }
    127         break;
    128 
    129     case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
    130         if (s->hit) {
    131             if (mt == SSL3_MT_FINISHED) {
    132                 st->hand_state = TLS_ST_CR_FINISHED;
    133                 return 1;
    134             }
    135         } else {
    136             if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
    137                 st->hand_state = TLS_ST_CR_CERT_REQ;
    138                 return 1;
    139             }
    140             if (mt == SSL3_MT_CERTIFICATE) {
    141                 st->hand_state = TLS_ST_CR_CERT;
    142                 return 1;
    143             }
    144 #ifndef OPENSSL_NO_COMP_ALG
    145             if (mt == SSL3_MT_COMPRESSED_CERTIFICATE
    146                 && s->ext.compress_certificate_sent) {
    147                 st->hand_state = TLS_ST_CR_COMP_CERT;
    148                 return 1;
    149             }
    150 #endif
    151         }
    152         break;
    153 
    154     case TLS_ST_CR_CERT_REQ:
    155         if (mt == SSL3_MT_CERTIFICATE) {
    156             st->hand_state = TLS_ST_CR_CERT;
    157             return 1;
    158         }
    159 #ifndef OPENSSL_NO_COMP_ALG
    160         if (mt == SSL3_MT_COMPRESSED_CERTIFICATE
    161             && s->ext.compress_certificate_sent) {
    162             st->hand_state = TLS_ST_CR_COMP_CERT;
    163             return 1;
    164         }
    165 #endif
    166         break;
    167 
    168     case TLS_ST_CR_CERT:
    169     case TLS_ST_CR_COMP_CERT:
    170         if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
    171             st->hand_state = TLS_ST_CR_CERT_VRFY;
    172             return 1;
    173         }
    174         break;
    175 
    176     case TLS_ST_CR_CERT_VRFY:
    177         if (mt == SSL3_MT_FINISHED) {
    178             st->hand_state = TLS_ST_CR_FINISHED;
    179             return 1;
    180         }
    181         break;
    182 
    183     case TLS_ST_OK:
    184         if (mt == SSL3_MT_NEWSESSION_TICKET) {
    185             st->hand_state = TLS_ST_CR_SESSION_TICKET;
    186             return 1;
    187         }
    188         if (mt == SSL3_MT_KEY_UPDATE && !SSL_IS_QUIC_HANDSHAKE(s)) {
    189             st->hand_state = TLS_ST_CR_KEY_UPDATE;
    190             return 1;
    191         }
    192         if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
    193 #if DTLS_MAX_VERSION_INTERNAL != DTLS1_2_VERSION
    194             /* Restore digest for PHA before adding message.*/
    195 #error Internal DTLS version error
    196 #endif
    197             if (!SSL_CONNECTION_IS_DTLS(s)
    198                 && s->post_handshake_auth == SSL_PHA_EXT_SENT) {
    199                 s->post_handshake_auth = SSL_PHA_REQUESTED;
    200                 /*
    201                  * In TLS, this is called before the message is added to the
    202                  * digest. In DTLS, this is expected to be called after adding
    203                  * to the digest. Either move the digest restore, or add the
    204                  * message here after the swap, or do it after the clientFinished?
    205                  */
    206                 if (!tls13_restore_handshake_digest_for_pha(s)) {
    207                     /* SSLfatal() already called */
    208                     return 0;
    209                 }
    210                 st->hand_state = TLS_ST_CR_CERT_REQ;
    211                 return 1;
    212             }
    213         }
    214         break;
    215     }
    216 
    217     /* No valid transition found */
    218     return 0;
    219 }
    220 
    221 /*
    222  * ossl_statem_client_read_transition() encapsulates the logic for the allowed
    223  * handshake state transitions when the client is reading messages from the
    224  * server. The message type that the server has sent is provided in |mt|. The
    225  * current state is in |s->statem.hand_state|.
    226  *
    227  * Return values are 1 for success (transition allowed) and  0 on error
    228  * (transition not allowed)
    229  */
    230 int ossl_statem_client_read_transition(SSL_CONNECTION *s, int mt)
    231 {
    232     OSSL_STATEM *st = &s->statem;
    233     int ske_expected;
    234 
    235     /*
    236      * Note that after writing the first ClientHello we don't know what version
    237      * we are going to negotiate yet, so we don't take this branch until later.
    238      */
    239     if (SSL_CONNECTION_IS_TLS13(s)) {
    240         if (!ossl_statem_client13_read_transition(s, mt))
    241             goto err;
    242         return 1;
    243     }
    244 
    245     switch (st->hand_state) {
    246     default:
    247         break;
    248 
    249     case TLS_ST_CW_CLNT_HELLO:
    250         if (mt == SSL3_MT_SERVER_HELLO) {
    251             st->hand_state = TLS_ST_CR_SRVR_HELLO;
    252             return 1;
    253         }
    254 
    255         if (SSL_CONNECTION_IS_DTLS(s)) {
    256             if (mt == DTLS1_MT_HELLO_VERIFY_REQUEST) {
    257                 st->hand_state = DTLS_ST_CR_HELLO_VERIFY_REQUEST;
    258                 return 1;
    259             }
    260         }
    261         break;
    262 
    263     case TLS_ST_EARLY_DATA:
    264         /*
    265          * We've not actually selected TLSv1.3 yet, but we have sent early
    266          * data. The only thing allowed now is a ServerHello or a
    267          * HelloRetryRequest.
    268          */
    269         if (mt == SSL3_MT_SERVER_HELLO) {
    270             st->hand_state = TLS_ST_CR_SRVR_HELLO;
    271             return 1;
    272         }
    273         break;
    274 
    275     case TLS_ST_CR_SRVR_HELLO:
    276         if (s->hit) {
    277             if (s->ext.ticket_expected) {
    278                 if (mt == SSL3_MT_NEWSESSION_TICKET) {
    279                     st->hand_state = TLS_ST_CR_SESSION_TICKET;
    280                     return 1;
    281                 }
    282             } else if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
    283                 st->hand_state = TLS_ST_CR_CHANGE;
    284                 return 1;
    285             }
    286         } else {
    287             if (SSL_CONNECTION_IS_DTLS(s)
    288                 && mt == DTLS1_MT_HELLO_VERIFY_REQUEST) {
    289                 st->hand_state = DTLS_ST_CR_HELLO_VERIFY_REQUEST;
    290                 return 1;
    291             } else if (s->version >= TLS1_VERSION
    292                 && s->ext.session_secret_cb != NULL
    293                 && s->session->ext.tick != NULL
    294                 && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
    295                 /*
    296                  * Normally, we can tell if the server is resuming the session
    297                  * from the session ID. EAP-FAST (RFC 4851), however, relies on
    298                  * the next server message after the ServerHello to determine if
    299                  * the server is resuming.
    300                  */
    301                 s->hit = 1;
    302                 st->hand_state = TLS_ST_CR_CHANGE;
    303                 return 1;
    304             } else if (!(s->s3.tmp.new_cipher->algorithm_auth
    305                            & (SSL_aNULL | SSL_aSRP | SSL_aPSK))) {
    306                 if (mt == SSL3_MT_CERTIFICATE) {
    307                     st->hand_state = TLS_ST_CR_CERT;
    308                     return 1;
    309                 }
    310             } else {
    311                 ske_expected = key_exchange_expected(s);
    312                 /* SKE is optional for some PSK ciphersuites */
    313                 if (ske_expected
    314                     || ((s->s3.tmp.new_cipher->algorithm_mkey & SSL_PSK)
    315                         && mt == SSL3_MT_SERVER_KEY_EXCHANGE)) {
    316                     if (mt == SSL3_MT_SERVER_KEY_EXCHANGE) {
    317                         st->hand_state = TLS_ST_CR_KEY_EXCH;
    318                         return 1;
    319                     }
    320                 } else if (mt == SSL3_MT_CERTIFICATE_REQUEST
    321                     && cert_req_allowed(s)) {
    322                     st->hand_state = TLS_ST_CR_CERT_REQ;
    323                     return 1;
    324                 } else if (mt == SSL3_MT_SERVER_DONE) {
    325                     st->hand_state = TLS_ST_CR_SRVR_DONE;
    326                     return 1;
    327                 }
    328             }
    329         }
    330         break;
    331 
    332     case TLS_ST_CR_CERT:
    333     case TLS_ST_CR_COMP_CERT:
    334         /*
    335          * The CertificateStatus message is optional even if
    336          * |ext.status_expected| is set
    337          */
    338         if (s->ext.status_expected && mt == SSL3_MT_CERTIFICATE_STATUS) {
    339             st->hand_state = TLS_ST_CR_CERT_STATUS;
    340             return 1;
    341         }
    342         /* Fall through */
    343 
    344     case TLS_ST_CR_CERT_STATUS:
    345         ske_expected = key_exchange_expected(s);
    346         /* SKE is optional for some PSK ciphersuites */
    347         if (ske_expected || ((s->s3.tmp.new_cipher->algorithm_mkey & SSL_PSK) && mt == SSL3_MT_SERVER_KEY_EXCHANGE)) {
    348             if (mt == SSL3_MT_SERVER_KEY_EXCHANGE) {
    349                 st->hand_state = TLS_ST_CR_KEY_EXCH;
    350                 return 1;
    351             }
    352             goto err;
    353         }
    354         /* Fall through */
    355 
    356     case TLS_ST_CR_KEY_EXCH:
    357         if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
    358             if (cert_req_allowed(s)) {
    359                 st->hand_state = TLS_ST_CR_CERT_REQ;
    360                 return 1;
    361             }
    362             goto err;
    363         }
    364         /* Fall through */
    365 
    366     case TLS_ST_CR_CERT_REQ:
    367         if (mt == SSL3_MT_SERVER_DONE) {
    368             st->hand_state = TLS_ST_CR_SRVR_DONE;
    369             return 1;
    370         }
    371         break;
    372 
    373     case TLS_ST_CW_FINISHED:
    374         if (s->ext.ticket_expected) {
    375             if (mt == SSL3_MT_NEWSESSION_TICKET) {
    376                 st->hand_state = TLS_ST_CR_SESSION_TICKET;
    377                 return 1;
    378             }
    379         } else if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
    380             st->hand_state = TLS_ST_CR_CHANGE;
    381             return 1;
    382         }
    383         break;
    384 
    385     case TLS_ST_CR_SESSION_TICKET:
    386         if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
    387             st->hand_state = TLS_ST_CR_CHANGE;
    388             return 1;
    389         }
    390         break;
    391 
    392     case TLS_ST_CR_CHANGE:
    393         if (mt == SSL3_MT_FINISHED) {
    394             st->hand_state = TLS_ST_CR_FINISHED;
    395             return 1;
    396         }
    397         break;
    398 
    399     case TLS_ST_OK:
    400         if (mt == SSL3_MT_HELLO_REQUEST) {
    401             st->hand_state = TLS_ST_CR_HELLO_REQ;
    402             return 1;
    403         }
    404         break;
    405     }
    406 
    407 err:
    408     /* No valid transition found */
    409     if (SSL_CONNECTION_IS_DTLS(s) && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
    410         BIO *rbio;
    411 
    412         /*
    413          * CCS messages don't have a message sequence number so this is probably
    414          * because of an out-of-order CCS. We'll just drop it.
    415          */
    416         s->init_num = 0;
    417         s->rwstate = SSL_READING;
    418         rbio = SSL_get_rbio(SSL_CONNECTION_GET_SSL(s));
    419         BIO_clear_retry_flags(rbio);
    420         BIO_set_retry_read(rbio);
    421         return 0;
    422     }
    423     SSLfatal(s, SSL3_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
    424     return 0;
    425 }
    426 
    427 static int do_compressed_cert(SSL_CONNECTION *sc)
    428 {
    429     /* If we negotiated RPK, we won't try to compress it */
    430     return sc->ext.client_cert_type == TLSEXT_cert_type_x509
    431         && sc->ext.compress_certificate_from_peer[0] != TLSEXT_comp_cert_none;
    432 }
    433 
    434 /*
    435  * ossl_statem_client13_write_transition() works out what handshake state to
    436  * move to next when the TLSv1.3 client is writing messages to be sent to the
    437  * server.
    438  */
    439 static WRITE_TRAN ossl_statem_client13_write_transition(SSL_CONNECTION *s)
    440 {
    441     OSSL_STATEM *st = &s->statem;
    442 
    443     /*
    444      * Note: There are no cases for TLS_ST_BEFORE because we haven't negotiated
    445      * TLSv1.3 yet at that point. They are handled by
    446      * ossl_statem_client_write_transition().
    447      */
    448     switch (st->hand_state) {
    449     default:
    450         /* Shouldn't happen */
    451         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
    452         return WRITE_TRAN_ERROR;
    453 
    454     case TLS_ST_CR_CERT_REQ:
    455         if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
    456             if (do_compressed_cert(s))
    457                 st->hand_state = TLS_ST_CW_COMP_CERT;
    458             else
    459                 st->hand_state = TLS_ST_CW_CERT;
    460             return WRITE_TRAN_CONTINUE;
    461         }
    462         /*
    463          * We should only get here if we received a CertificateRequest after
    464          * we already sent close_notify
    465          */
    466         if (!ossl_assert((s->shutdown & SSL_SENT_SHUTDOWN) != 0)) {
    467             /* Shouldn't happen - same as default case */
    468             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
    469             return WRITE_TRAN_ERROR;
    470         }
    471         st->hand_state = TLS_ST_OK;
    472         return WRITE_TRAN_CONTINUE;
    473 
    474     case TLS_ST_CR_FINISHED:
    475         if (s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY
    476             || s->early_data_state == SSL_EARLY_DATA_FINISHED_WRITING)
    477             st->hand_state = TLS_ST_PENDING_EARLY_DATA_END;
    478         else if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
    479             && s->hello_retry_request == SSL_HRR_NONE)
    480             st->hand_state = TLS_ST_CW_CHANGE;
    481         else if (s->s3.tmp.cert_req == 0)
    482             st->hand_state = TLS_ST_CW_FINISHED;
    483         else if (do_compressed_cert(s))
    484             st->hand_state = TLS_ST_CW_COMP_CERT;
    485         else
    486             st->hand_state = TLS_ST_CW_CERT;
    487 
    488         s->ts_msg_read = ossl_time_now();
    489         return WRITE_TRAN_CONTINUE;
    490 
    491     case TLS_ST_PENDING_EARLY_DATA_END:
    492         if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED && !SSL_NO_EOED(s)) {
    493             st->hand_state = TLS_ST_CW_END_OF_EARLY_DATA;
    494             return WRITE_TRAN_CONTINUE;
    495         }
    496         /* Fall through */
    497 
    498     case TLS_ST_CW_END_OF_EARLY_DATA:
    499     case TLS_ST_CW_CHANGE:
    500         if (s->s3.tmp.cert_req == 0)
    501             st->hand_state = TLS_ST_CW_FINISHED;
    502         else if (do_compressed_cert(s))
    503             st->hand_state = TLS_ST_CW_COMP_CERT;
    504         else
    505             st->hand_state = TLS_ST_CW_CERT;
    506         return WRITE_TRAN_CONTINUE;
    507 
    508     case TLS_ST_CW_COMP_CERT:
    509     case TLS_ST_CW_CERT:
    510         /* If a non-empty Certificate we also send CertificateVerify */
    511         st->hand_state = (s->s3.tmp.cert_req == 1) ? TLS_ST_CW_CERT_VRFY
    512                                                    : TLS_ST_CW_FINISHED;
    513         return WRITE_TRAN_CONTINUE;
    514 
    515     case TLS_ST_CW_CERT_VRFY:
    516         st->hand_state = TLS_ST_CW_FINISHED;
    517         return WRITE_TRAN_CONTINUE;
    518 
    519     case TLS_ST_CR_KEY_UPDATE:
    520     case TLS_ST_CW_KEY_UPDATE:
    521     case TLS_ST_CR_SESSION_TICKET:
    522     case TLS_ST_CW_FINISHED:
    523         st->hand_state = TLS_ST_OK;
    524         return WRITE_TRAN_CONTINUE;
    525 
    526     case TLS_ST_OK:
    527         if (s->key_update != SSL_KEY_UPDATE_NONE) {
    528             st->hand_state = TLS_ST_CW_KEY_UPDATE;
    529             return WRITE_TRAN_CONTINUE;
    530         }
    531 
    532         /* Try to read from the server instead */
    533         return WRITE_TRAN_FINISHED;
    534     }
    535 }
    536 
    537 /*
    538  * ossl_statem_client_write_transition() works out what handshake state to
    539  * move to next when the client is writing messages to be sent to the server.
    540  */
    541 WRITE_TRAN ossl_statem_client_write_transition(SSL_CONNECTION *s)
    542 {
    543     OSSL_STATEM *st = &s->statem;
    544 
    545     /*
    546      * Note that immediately before/after a ClientHello we don't know what
    547      * version we are going to negotiate yet, so we don't take this branch until
    548      * later
    549      */
    550     if (SSL_CONNECTION_IS_TLS13(s))
    551         return ossl_statem_client13_write_transition(s);
    552 
    553     switch (st->hand_state) {
    554     default:
    555         /* Shouldn't happen */
    556         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
    557         return WRITE_TRAN_ERROR;
    558 
    559     case TLS_ST_OK:
    560         if (!s->renegotiate) {
    561             /*
    562              * We haven't requested a renegotiation ourselves so we must have
    563              * received a message from the server. Better read it.
    564              */
    565             return WRITE_TRAN_FINISHED;
    566         }
    567         /* Renegotiation */
    568         /* fall thru */
    569     case TLS_ST_BEFORE:
    570         st->hand_state = TLS_ST_CW_CLNT_HELLO;
    571         return WRITE_TRAN_CONTINUE;
    572 
    573     case TLS_ST_CW_CLNT_HELLO:
    574         if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
    575             && !SSL_IS_QUIC_HANDSHAKE(s)) {
    576             /*
    577              * We are assuming this is a TLSv1.3 connection, although we haven't
    578              * actually selected a version yet.
    579              */
    580             if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0)
    581                 st->hand_state = TLS_ST_CW_CHANGE;
    582             else
    583                 st->hand_state = TLS_ST_EARLY_DATA;
    584             return WRITE_TRAN_CONTINUE;
    585         }
    586         /*
    587          * No transition at the end of writing because we don't know what
    588          * we will be sent
    589          */
    590         s->ts_msg_write = ossl_time_now();
    591         return WRITE_TRAN_FINISHED;
    592 
    593     case TLS_ST_CR_SRVR_HELLO:
    594         /*
    595          * We only get here in TLSv1.3. We just received an HRR, so issue a
    596          * CCS unless middlebox compat mode is off, or we already issued one
    597          * because we did early data.
    598          */
    599         if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
    600             && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING)
    601             st->hand_state = TLS_ST_CW_CHANGE;
    602         else
    603             st->hand_state = TLS_ST_CW_CLNT_HELLO;
    604         return WRITE_TRAN_CONTINUE;
    605 
    606     case TLS_ST_EARLY_DATA:
    607         s->ts_msg_write = ossl_time_now();
    608         return WRITE_TRAN_FINISHED;
    609 
    610     case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
    611         st->hand_state = TLS_ST_CW_CLNT_HELLO;
    612         return WRITE_TRAN_CONTINUE;
    613 
    614     case TLS_ST_CR_SRVR_DONE:
    615         s->ts_msg_read = ossl_time_now();
    616         if (s->s3.tmp.cert_req)
    617             st->hand_state = TLS_ST_CW_CERT;
    618         else
    619             st->hand_state = TLS_ST_CW_KEY_EXCH;
    620         return WRITE_TRAN_CONTINUE;
    621 
    622     case TLS_ST_CW_CERT:
    623         st->hand_state = TLS_ST_CW_KEY_EXCH;
    624         return WRITE_TRAN_CONTINUE;
    625 
    626     case TLS_ST_CW_KEY_EXCH:
    627         /*
    628          * For TLS, cert_req is set to 2, so a cert chain of nothing is
    629          * sent, but no verify packet is sent
    630          */
    631         /*
    632          * XXX: For now, we do not support client authentication in ECDH
    633          * cipher suites with ECDH (rather than ECDSA) certificates. We
    634          * need to skip the certificate verify message when client's
    635          * ECDH public key is sent inside the client certificate.
    636          */
    637         if (s->s3.tmp.cert_req == 1) {
    638             st->hand_state = TLS_ST_CW_CERT_VRFY;
    639         } else {
    640             st->hand_state = TLS_ST_CW_CHANGE;
    641         }
    642         if (s->s3.flags & TLS1_FLAGS_SKIP_CERT_VERIFY) {
    643             st->hand_state = TLS_ST_CW_CHANGE;
    644         }
    645         return WRITE_TRAN_CONTINUE;
    646 
    647     case TLS_ST_CW_CERT_VRFY:
    648         st->hand_state = TLS_ST_CW_CHANGE;
    649         return WRITE_TRAN_CONTINUE;
    650 
    651     case TLS_ST_CW_CHANGE:
    652         if (s->hello_retry_request == SSL_HRR_PENDING) {
    653             st->hand_state = TLS_ST_CW_CLNT_HELLO;
    654         } else if (s->early_data_state == SSL_EARLY_DATA_CONNECTING) {
    655             st->hand_state = TLS_ST_EARLY_DATA;
    656         } else {
    657 #if defined(OPENSSL_NO_NEXTPROTONEG)
    658             st->hand_state = TLS_ST_CW_FINISHED;
    659 #else
    660             if (!SSL_CONNECTION_IS_DTLS(s) && s->s3.npn_seen)
    661                 st->hand_state = TLS_ST_CW_NEXT_PROTO;
    662             else
    663                 st->hand_state = TLS_ST_CW_FINISHED;
    664 #endif
    665         }
    666         return WRITE_TRAN_CONTINUE;
    667 
    668 #if !defined(OPENSSL_NO_NEXTPROTONEG)
    669     case TLS_ST_CW_NEXT_PROTO:
    670         st->hand_state = TLS_ST_CW_FINISHED;
    671         return WRITE_TRAN_CONTINUE;
    672 #endif
    673 
    674     case TLS_ST_CW_FINISHED:
    675         if (s->hit) {
    676             st->hand_state = TLS_ST_OK;
    677             return WRITE_TRAN_CONTINUE;
    678         } else {
    679             return WRITE_TRAN_FINISHED;
    680         }
    681 
    682     case TLS_ST_CR_FINISHED:
    683         if (s->hit) {
    684             st->hand_state = TLS_ST_CW_CHANGE;
    685             return WRITE_TRAN_CONTINUE;
    686         } else {
    687             st->hand_state = TLS_ST_OK;
    688             return WRITE_TRAN_CONTINUE;
    689         }
    690 
    691     case TLS_ST_CR_HELLO_REQ:
    692         /*
    693          * If we can renegotiate now then do so, otherwise wait for a more
    694          * convenient time.
    695          */
    696         if (ssl3_renegotiate_check(SSL_CONNECTION_GET_SSL(s), 1)) {
    697             if (!tls_setup_handshake(s)) {
    698                 /* SSLfatal() already called */
    699                 return WRITE_TRAN_ERROR;
    700             }
    701             st->hand_state = TLS_ST_CW_CLNT_HELLO;
    702             return WRITE_TRAN_CONTINUE;
    703         }
    704         st->hand_state = TLS_ST_OK;
    705         return WRITE_TRAN_CONTINUE;
    706     }
    707 }
    708 
    709 /*
    710  * Perform any pre work that needs to be done prior to sending a message from
    711  * the client to the server.
    712  */
    713 WORK_STATE ossl_statem_client_pre_work(SSL_CONNECTION *s, WORK_STATE wst)
    714 {
    715     OSSL_STATEM *st = &s->statem;
    716 
    717     switch (st->hand_state) {
    718     default:
    719         /* No pre work to be done */
    720         break;
    721 
    722     case TLS_ST_CW_CLNT_HELLO:
    723         s->shutdown = 0;
    724         if (SSL_CONNECTION_IS_DTLS(s)) {
    725             /* every DTLS ClientHello resets Finished MAC */
    726             if (!ssl3_init_finished_mac(s)) {
    727                 /* SSLfatal() already called */
    728                 return WORK_ERROR;
    729             }
    730         } else if (s->ext.early_data == SSL_EARLY_DATA_REJECTED) {
    731             /*
    732              * This must be a second ClientHello after an HRR following an
    733              * earlier rejected attempt to send early data. Since we were
    734              * previously encrypting the early data we now need to reset the
    735              * write record layer in order to write in plaintext again.
    736              */
    737             if (!ssl_set_new_record_layer(s,
    738                     TLS_ANY_VERSION,
    739                     OSSL_RECORD_DIRECTION_WRITE,
    740                     OSSL_RECORD_PROTECTION_LEVEL_NONE,
    741                     NULL, 0, NULL, 0, NULL, 0, NULL, 0,
    742                     NULL, 0, NID_undef, NULL, NULL,
    743                     NULL)) {
    744                 /* SSLfatal already called */
    745                 return WORK_ERROR;
    746             }
    747         }
    748         break;
    749 
    750     case TLS_ST_CW_CHANGE:
    751         if (SSL_CONNECTION_IS_DTLS(s)) {
    752             if (s->hit) {
    753                 /*
    754                  * We're into the last flight so we don't retransmit these
    755                  * messages unless we need to.
    756                  */
    757                 st->use_timer = 0;
    758             }
    759 #ifndef OPENSSL_NO_SCTP
    760             if (BIO_dgram_is_sctp(SSL_get_wbio(SSL_CONNECTION_GET_SSL(s)))) {
    761                 /* Calls SSLfatal() as required */
    762                 return dtls_wait_for_dry(s);
    763             }
    764 #endif
    765         }
    766         break;
    767 
    768     case TLS_ST_PENDING_EARLY_DATA_END:
    769         /*
    770          * If we've been called by SSL_do_handshake()/SSL_write(), or we did not
    771          * attempt to write early data before calling SSL_read() then we press
    772          * on with the handshake. Otherwise we pause here.
    773          */
    774         if (s->early_data_state == SSL_EARLY_DATA_FINISHED_WRITING
    775             || s->early_data_state == SSL_EARLY_DATA_NONE)
    776             return WORK_FINISHED_CONTINUE;
    777         /* Fall through */
    778 
    779     case TLS_ST_EARLY_DATA:
    780         return tls_finish_handshake(s, wst, 0, 1);
    781 
    782     case TLS_ST_OK:
    783         /* Calls SSLfatal() as required */
    784         return tls_finish_handshake(s, wst, 1, 1);
    785     }
    786 
    787     return WORK_FINISHED_CONTINUE;
    788 }
    789 
    790 /*
    791  * Perform any work that needs to be done after sending a message from the
    792  * client to the server.
    793  */
    794 WORK_STATE ossl_statem_client_post_work(SSL_CONNECTION *s, WORK_STATE wst)
    795 {
    796     OSSL_STATEM *st = &s->statem;
    797     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
    798 
    799     s->init_num = 0;
    800 
    801     switch (st->hand_state) {
    802     default:
    803         /* No post work to be done */
    804         break;
    805 
    806     case TLS_ST_CW_CLNT_HELLO:
    807         if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
    808             && s->max_early_data > 0) {
    809             /*
    810              * We haven't selected TLSv1.3 yet so we don't call the change
    811              * cipher state function associated with the SSL_METHOD. Instead
    812              * we call tls13_change_cipher_state() directly.
    813              */
    814             if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) == 0) {
    815                 if (!tls13_change_cipher_state(s,
    816                         SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
    817                     /* SSLfatal() already called */
    818                     return WORK_ERROR;
    819                 }
    820             }
    821             /* else we're in compat mode so we delay flushing until after CCS */
    822         } else if (!statem_flush(s)) {
    823             return WORK_MORE_A;
    824         }
    825 
    826         if (SSL_CONNECTION_IS_DTLS(s)) {
    827             /* Treat the next message as the first packet */
    828             s->first_packet = 1;
    829         }
    830         break;
    831 
    832     case TLS_ST_CW_KEY_EXCH:
    833         if (tls_client_key_exchange_post_work(s) == 0) {
    834             /* SSLfatal() already called */
    835             return WORK_ERROR;
    836         }
    837         break;
    838 
    839     case TLS_ST_CW_CHANGE:
    840         if (SSL_CONNECTION_IS_TLS13(s)
    841             || s->hello_retry_request == SSL_HRR_PENDING)
    842             break;
    843         if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
    844             && s->max_early_data > 0) {
    845             /*
    846              * We haven't selected TLSv1.3 yet so we don't call the change
    847              * cipher state function associated with the SSL_METHOD. Instead
    848              * we call tls13_change_cipher_state() directly.
    849              */
    850             if (!tls13_change_cipher_state(s,
    851                     SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_CLIENT_WRITE))
    852                 return WORK_ERROR;
    853             break;
    854         }
    855         s->session->cipher = s->s3.tmp.new_cipher;
    856 #ifdef OPENSSL_NO_COMP
    857         s->session->compress_meth = 0;
    858 #else
    859         if (s->s3.tmp.new_compression == NULL)
    860             s->session->compress_meth = 0;
    861         else
    862             s->session->compress_meth = s->s3.tmp.new_compression->id;
    863 #endif
    864         if (!ssl->method->ssl3_enc->setup_key_block(s)) {
    865             /* SSLfatal() already called */
    866             return WORK_ERROR;
    867         }
    868 
    869         if (!ssl->method->ssl3_enc->change_cipher_state(s,
    870                 SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
    871             /* SSLfatal() already called */
    872             return WORK_ERROR;
    873         }
    874 
    875 #ifndef OPENSSL_NO_SCTP
    876         if (SSL_CONNECTION_IS_DTLS(s) && s->hit) {
    877             /*
    878              * Change to new shared key of SCTP-Auth, will be ignored if
    879              * no SCTP used.
    880              */
    881             BIO_ctrl(SSL_get_wbio(ssl), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
    882                 0, NULL);
    883         }
    884 #endif
    885         break;
    886 
    887     case TLS_ST_CW_FINISHED:
    888 #ifndef OPENSSL_NO_SCTP
    889         if (wst == WORK_MORE_A && SSL_CONNECTION_IS_DTLS(s) && s->hit == 0) {
    890             /*
    891              * Change to new shared key of SCTP-Auth, will be ignored if
    892              * no SCTP used.
    893              */
    894             BIO_ctrl(SSL_get_wbio(ssl), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
    895                 0, NULL);
    896         }
    897 #endif
    898         if (statem_flush(s) != 1)
    899             return WORK_MORE_B;
    900 
    901         if (SSL_CONNECTION_IS_TLS13(s)) {
    902             if (!tls13_save_handshake_digest_for_pha(s)) {
    903                 /* SSLfatal() already called */
    904                 return WORK_ERROR;
    905             }
    906             if (s->post_handshake_auth != SSL_PHA_REQUESTED) {
    907                 if (!ssl->method->ssl3_enc->change_cipher_state(s,
    908                         SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
    909                     /* SSLfatal() already called */
    910                     return WORK_ERROR;
    911                 }
    912                 /*
    913                  * For QUIC we deferred setting up these keys until now so
    914                  * that we can ensure write keys are always set up before read
    915                  * keys.
    916                  */
    917                 if (SSL_IS_QUIC_HANDSHAKE(s)
    918                     && !ssl->method->ssl3_enc->change_cipher_state(s,
    919                         SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_CLIENT_READ)) {
    920                     /* SSLfatal() already called */
    921                     return WORK_ERROR;
    922                 }
    923             }
    924         }
    925         break;
    926 
    927     case TLS_ST_CW_KEY_UPDATE:
    928         if (statem_flush(s) != 1)
    929             return WORK_MORE_A;
    930         if (!tls13_update_key(s, 1)) {
    931             /* SSLfatal() already called */
    932             return WORK_ERROR;
    933         }
    934         break;
    935     }
    936 
    937     return WORK_FINISHED_CONTINUE;
    938 }
    939 
    940 /*
    941  * Get the message construction function and message type for sending from the
    942  * client
    943  *
    944  * Valid return values are:
    945  *   1: Success
    946  *   0: Error
    947  */
    948 int ossl_statem_client_construct_message(SSL_CONNECTION *s,
    949     confunc_f *confunc, int *mt)
    950 {
    951     OSSL_STATEM *st = &s->statem;
    952 
    953     switch (st->hand_state) {
    954     default:
    955         /* Shouldn't happen */
    956         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_STATE);
    957         return 0;
    958 
    959     case TLS_ST_CW_CHANGE:
    960         if (SSL_CONNECTION_IS_DTLS(s))
    961             *confunc = dtls_construct_change_cipher_spec;
    962         else
    963             *confunc = tls_construct_change_cipher_spec;
    964         *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
    965         break;
    966 
    967     case TLS_ST_CW_CLNT_HELLO:
    968         *confunc = tls_construct_client_hello;
    969         *mt = SSL3_MT_CLIENT_HELLO;
    970         break;
    971 
    972     case TLS_ST_CW_END_OF_EARLY_DATA:
    973         *confunc = tls_construct_end_of_early_data;
    974         *mt = SSL3_MT_END_OF_EARLY_DATA;
    975         break;
    976 
    977     case TLS_ST_PENDING_EARLY_DATA_END:
    978         *confunc = NULL;
    979         *mt = SSL3_MT_DUMMY;
    980         break;
    981 
    982     case TLS_ST_CW_CERT:
    983         *confunc = tls_construct_client_certificate;
    984         *mt = SSL3_MT_CERTIFICATE;
    985         break;
    986 
    987 #ifndef OPENSSL_NO_COMP_ALG
    988     case TLS_ST_CW_COMP_CERT:
    989         *confunc = tls_construct_client_compressed_certificate;
    990         *mt = SSL3_MT_COMPRESSED_CERTIFICATE;
    991         break;
    992 #endif
    993 
    994     case TLS_ST_CW_KEY_EXCH:
    995         *confunc = tls_construct_client_key_exchange;
    996         *mt = SSL3_MT_CLIENT_KEY_EXCHANGE;
    997         break;
    998 
    999     case TLS_ST_CW_CERT_VRFY:
   1000         *confunc = tls_construct_cert_verify;
   1001         *mt = SSL3_MT_CERTIFICATE_VERIFY;
   1002         break;
   1003 
   1004 #if !defined(OPENSSL_NO_NEXTPROTONEG)
   1005     case TLS_ST_CW_NEXT_PROTO:
   1006         *confunc = tls_construct_next_proto;
   1007         *mt = SSL3_MT_NEXT_PROTO;
   1008         break;
   1009 #endif
   1010     case TLS_ST_CW_FINISHED:
   1011         *confunc = tls_construct_finished;
   1012         *mt = SSL3_MT_FINISHED;
   1013         break;
   1014 
   1015     case TLS_ST_CW_KEY_UPDATE:
   1016         *confunc = tls_construct_key_update;
   1017         *mt = SSL3_MT_KEY_UPDATE;
   1018         break;
   1019     }
   1020 
   1021     return 1;
   1022 }
   1023 
   1024 /*
   1025  * Returns the maximum allowed length for the current message that we are
   1026  * reading. Excludes the message header.
   1027  */
   1028 size_t ossl_statem_client_max_message_size(SSL_CONNECTION *s)
   1029 {
   1030     OSSL_STATEM *st = &s->statem;
   1031 
   1032     switch (st->hand_state) {
   1033     default:
   1034         /* Shouldn't happen */
   1035         return 0;
   1036 
   1037     case TLS_ST_CR_SRVR_HELLO:
   1038         return SERVER_HELLO_MAX_LENGTH;
   1039 
   1040     case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
   1041         return HELLO_VERIFY_REQUEST_MAX_LENGTH;
   1042 
   1043     case TLS_ST_CR_COMP_CERT:
   1044     case TLS_ST_CR_CERT:
   1045         return s->max_cert_list;
   1046 
   1047     case TLS_ST_CR_CERT_VRFY:
   1048         return CERTIFICATE_VERIFY_MAX_LENGTH;
   1049 
   1050     case TLS_ST_CR_CERT_STATUS:
   1051         return SSL3_RT_MAX_PLAIN_LENGTH;
   1052 
   1053     case TLS_ST_CR_KEY_EXCH:
   1054         return SERVER_KEY_EXCH_MAX_LENGTH;
   1055 
   1056     case TLS_ST_CR_CERT_REQ:
   1057         /*
   1058          * Set to s->max_cert_list for compatibility with previous releases. In
   1059          * practice these messages can get quite long if servers are configured
   1060          * to provide a long list of acceptable CAs
   1061          */
   1062         return s->max_cert_list;
   1063 
   1064     case TLS_ST_CR_SRVR_DONE:
   1065         return SERVER_HELLO_DONE_MAX_LENGTH;
   1066 
   1067     case TLS_ST_CR_CHANGE:
   1068         if (s->version == DTLS1_BAD_VER)
   1069             return 3;
   1070         return CCS_MAX_LENGTH;
   1071 
   1072     case TLS_ST_CR_SESSION_TICKET:
   1073         return (SSL_CONNECTION_IS_TLS13(s)) ? SESSION_TICKET_MAX_LENGTH_TLS13
   1074                                             : SESSION_TICKET_MAX_LENGTH_TLS12;
   1075 
   1076     case TLS_ST_CR_FINISHED:
   1077         return FINISHED_MAX_LENGTH;
   1078 
   1079     case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
   1080         return ENCRYPTED_EXTENSIONS_MAX_LENGTH;
   1081 
   1082     case TLS_ST_CR_KEY_UPDATE:
   1083         return KEY_UPDATE_MAX_LENGTH;
   1084     }
   1085 }
   1086 
   1087 /*
   1088  * Process a message that the client has received from the server.
   1089  */
   1090 MSG_PROCESS_RETURN ossl_statem_client_process_message(SSL_CONNECTION *s,
   1091     PACKET *pkt)
   1092 {
   1093     OSSL_STATEM *st = &s->statem;
   1094 
   1095     switch (st->hand_state) {
   1096     default:
   1097         /* Shouldn't happen */
   1098         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1099         return MSG_PROCESS_ERROR;
   1100 
   1101     case TLS_ST_CR_SRVR_HELLO:
   1102         return tls_process_server_hello(s, pkt);
   1103 
   1104     case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
   1105         return dtls_process_hello_verify(s, pkt);
   1106 
   1107     case TLS_ST_CR_CERT:
   1108         return tls_process_server_certificate(s, pkt);
   1109 
   1110 #ifndef OPENSSL_NO_COMP_ALG
   1111     case TLS_ST_CR_COMP_CERT:
   1112         return tls_process_server_compressed_certificate(s, pkt);
   1113 #endif
   1114 
   1115     case TLS_ST_CR_CERT_VRFY:
   1116         return tls_process_cert_verify(s, pkt);
   1117 
   1118     case TLS_ST_CR_CERT_STATUS:
   1119         return tls_process_cert_status(s, pkt);
   1120 
   1121     case TLS_ST_CR_KEY_EXCH:
   1122         return tls_process_key_exchange(s, pkt);
   1123 
   1124     case TLS_ST_CR_CERT_REQ:
   1125         return tls_process_certificate_request(s, pkt);
   1126 
   1127     case TLS_ST_CR_SRVR_DONE:
   1128         return tls_process_server_done(s, pkt);
   1129 
   1130     case TLS_ST_CR_CHANGE:
   1131         return tls_process_change_cipher_spec(s, pkt);
   1132 
   1133     case TLS_ST_CR_SESSION_TICKET:
   1134         return tls_process_new_session_ticket(s, pkt);
   1135 
   1136     case TLS_ST_CR_FINISHED:
   1137         return tls_process_finished(s, pkt);
   1138 
   1139     case TLS_ST_CR_HELLO_REQ:
   1140         return tls_process_hello_req(s, pkt);
   1141 
   1142     case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
   1143         return tls_process_encrypted_extensions(s, pkt);
   1144 
   1145     case TLS_ST_CR_KEY_UPDATE:
   1146         return tls_process_key_update(s, pkt);
   1147     }
   1148 }
   1149 
   1150 /*
   1151  * Perform any further processing required following the receipt of a message
   1152  * from the server
   1153  */
   1154 WORK_STATE ossl_statem_client_post_process_message(SSL_CONNECTION *s,
   1155     WORK_STATE wst)
   1156 {
   1157     OSSL_STATEM *st = &s->statem;
   1158 
   1159     switch (st->hand_state) {
   1160     default:
   1161         /* Shouldn't happen */
   1162         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1163         return WORK_ERROR;
   1164 
   1165     case TLS_ST_CR_CERT:
   1166     case TLS_ST_CR_COMP_CERT:
   1167         return tls_post_process_server_certificate(s, wst);
   1168 
   1169     case TLS_ST_CR_CERT_VRFY:
   1170     case TLS_ST_CR_CERT_REQ:
   1171         return tls_prepare_client_certificate(s, wst);
   1172     }
   1173 }
   1174 
   1175 CON_FUNC_RETURN tls_construct_client_hello(SSL_CONNECTION *s, WPACKET *pkt)
   1176 {
   1177     unsigned char *p;
   1178     size_t sess_id_len;
   1179     int i, protverr;
   1180 #ifndef OPENSSL_NO_COMP
   1181     SSL_COMP *comp;
   1182 #endif
   1183     SSL_SESSION *sess = s->session;
   1184     unsigned char *session_id;
   1185     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   1186 
   1187     /* Work out what SSL/TLS/DTLS version to use */
   1188     protverr = ssl_set_client_hello_version(s);
   1189     if (protverr != 0) {
   1190         SSLfatal(s, SSL_AD_INTERNAL_ERROR, protverr);
   1191         return CON_FUNC_ERROR;
   1192     }
   1193 
   1194     if (sess == NULL
   1195         || !ssl_version_supported(s, sess->ssl_version, NULL)
   1196         || !SSL_SESSION_is_resumable(sess)) {
   1197         if (s->hello_retry_request == SSL_HRR_NONE
   1198             && !ssl_get_new_session(s, 0)) {
   1199             /* SSLfatal() already called */
   1200             return CON_FUNC_ERROR;
   1201         }
   1202     }
   1203     /* else use the pre-loaded session */
   1204 
   1205     p = s->s3.client_random;
   1206 
   1207     /*
   1208      * for DTLS if client_random is initialized, reuse it, we are
   1209      * required to use same upon reply to HelloVerify
   1210      */
   1211     if (SSL_CONNECTION_IS_DTLS(s)) {
   1212         size_t idx;
   1213         i = 1;
   1214         for (idx = 0; idx < sizeof(s->s3.client_random); idx++) {
   1215             if (p[idx]) {
   1216                 i = 0;
   1217                 break;
   1218             }
   1219         }
   1220     } else {
   1221         i = (s->hello_retry_request == SSL_HRR_NONE);
   1222     }
   1223 
   1224     if (i && ssl_fill_hello_random(s, 0, p, sizeof(s->s3.client_random), DOWNGRADE_NONE) <= 0) {
   1225         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1226         return CON_FUNC_ERROR;
   1227     }
   1228 
   1229     /*-
   1230      * version indicates the negotiated version: for example from
   1231      * an SSLv2/v3 compatible client hello). The client_version
   1232      * field is the maximum version we permit and it is also
   1233      * used in RSA encrypted premaster secrets. Some servers can
   1234      * choke if we initially report a higher version then
   1235      * renegotiate to a lower one in the premaster secret. This
   1236      * didn't happen with TLS 1.0 as most servers supported it
   1237      * but it can with TLS 1.1 or later if the server only supports
   1238      * 1.0.
   1239      *
   1240      * Possible scenario with previous logic:
   1241      *      1. Client hello indicates TLS 1.2
   1242      *      2. Server hello says TLS 1.0
   1243      *      3. RSA encrypted premaster secret uses 1.2.
   1244      *      4. Handshake proceeds using TLS 1.0.
   1245      *      5. Server sends hello request to renegotiate.
   1246      *      6. Client hello indicates TLS v1.0 as we now
   1247      *         know that is maximum server supports.
   1248      *      7. Server chokes on RSA encrypted premaster secret
   1249      *         containing version 1.0.
   1250      *
   1251      * For interoperability it should be OK to always use the
   1252      * maximum version we support in client hello and then rely
   1253      * on the checking of version to ensure the servers isn't
   1254      * being inconsistent: for example initially negotiating with
   1255      * TLS 1.0 and renegotiating with TLS 1.2. We do this by using
   1256      * client_version in client hello and not resetting it to
   1257      * the negotiated version.
   1258      *
   1259      * For TLS 1.3 we always set the ClientHello version to 1.2 and rely on the
   1260      * supported_versions extension for the real supported versions.
   1261      */
   1262     if (!WPACKET_put_bytes_u16(pkt, s->client_version)
   1263         || !WPACKET_memcpy(pkt, s->s3.client_random, SSL3_RANDOM_SIZE)) {
   1264         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1265         return CON_FUNC_ERROR;
   1266     }
   1267 
   1268     /* Session ID */
   1269     session_id = s->session->session_id;
   1270     if (s->new_session || s->session->ssl_version == TLS1_3_VERSION) {
   1271         if (s->version == TLS1_3_VERSION
   1272             && (s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0) {
   1273             sess_id_len = sizeof(s->tmp_session_id);
   1274             s->tmp_session_id_len = sess_id_len;
   1275             session_id = s->tmp_session_id;
   1276             if (s->hello_retry_request == SSL_HRR_NONE
   1277                 && RAND_bytes_ex(sctx->libctx, s->tmp_session_id,
   1278                        sess_id_len, 0)
   1279                     <= 0) {
   1280                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1281                 return CON_FUNC_ERROR;
   1282             }
   1283         } else {
   1284             sess_id_len = 0;
   1285         }
   1286     } else {
   1287         assert(s->session->session_id_length <= sizeof(s->session->session_id));
   1288         sess_id_len = s->session->session_id_length;
   1289         if (s->version == TLS1_3_VERSION) {
   1290             s->tmp_session_id_len = sess_id_len;
   1291             memcpy(s->tmp_session_id, s->session->session_id, sess_id_len);
   1292         }
   1293     }
   1294     if (!WPACKET_start_sub_packet_u8(pkt)
   1295         || (sess_id_len != 0 && !WPACKET_memcpy(pkt, session_id, sess_id_len))
   1296         || !WPACKET_close(pkt)) {
   1297         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1298         return CON_FUNC_ERROR;
   1299     }
   1300 
   1301     /* cookie stuff for DTLS */
   1302     if (SSL_CONNECTION_IS_DTLS(s)) {
   1303         if (s->d1->cookie_len > sizeof(s->d1->cookie)
   1304             || !WPACKET_sub_memcpy_u8(pkt, s->d1->cookie,
   1305                 s->d1->cookie_len)) {
   1306             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1307             return CON_FUNC_ERROR;
   1308         }
   1309     }
   1310 
   1311     /* Ciphers supported */
   1312     if (!WPACKET_start_sub_packet_u16(pkt)) {
   1313         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1314         return CON_FUNC_ERROR;
   1315     }
   1316 
   1317     if (!ssl_cipher_list_to_bytes(s, SSL_get_ciphers(SSL_CONNECTION_GET_SSL(s)),
   1318             pkt)) {
   1319         /* SSLfatal() already called */
   1320         return CON_FUNC_ERROR;
   1321     }
   1322     if (!WPACKET_close(pkt)) {
   1323         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1324         return CON_FUNC_ERROR;
   1325     }
   1326 
   1327     /* COMPRESSION */
   1328     if (!WPACKET_start_sub_packet_u8(pkt)) {
   1329         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1330         return CON_FUNC_ERROR;
   1331     }
   1332 #ifndef OPENSSL_NO_COMP
   1333     if (ssl_allow_compression(s)
   1334         && sctx->comp_methods
   1335         && (SSL_CONNECTION_IS_DTLS(s)
   1336             || s->s3.tmp.max_ver < TLS1_3_VERSION)) {
   1337         int compnum = sk_SSL_COMP_num(sctx->comp_methods);
   1338         for (i = 0; i < compnum; i++) {
   1339             comp = sk_SSL_COMP_value(sctx->comp_methods, i);
   1340             if (!WPACKET_put_bytes_u8(pkt, comp->id)) {
   1341                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1342                 return CON_FUNC_ERROR;
   1343             }
   1344         }
   1345     }
   1346 #endif
   1347     /* Add the NULL method */
   1348     if (!WPACKET_put_bytes_u8(pkt, 0) || !WPACKET_close(pkt)) {
   1349         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1350         return CON_FUNC_ERROR;
   1351     }
   1352 
   1353     /* TLS extensions */
   1354     if (!tls_construct_extensions(s, pkt, SSL_EXT_CLIENT_HELLO, NULL, 0)) {
   1355         /* SSLfatal() already called */
   1356         return CON_FUNC_ERROR;
   1357     }
   1358 
   1359     return CON_FUNC_SUCCESS;
   1360 }
   1361 
   1362 MSG_PROCESS_RETURN dtls_process_hello_verify(SSL_CONNECTION *s, PACKET *pkt)
   1363 {
   1364     size_t cookie_len;
   1365     PACKET cookiepkt;
   1366 
   1367     if (!PACKET_forward(pkt, 2)
   1368         || !PACKET_get_length_prefixed_1(pkt, &cookiepkt)) {
   1369         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   1370         return MSG_PROCESS_ERROR;
   1371     }
   1372 
   1373     cookie_len = PACKET_remaining(&cookiepkt);
   1374     if (cookie_len > sizeof(s->d1->cookie)) {
   1375         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_LENGTH_TOO_LONG);
   1376         return MSG_PROCESS_ERROR;
   1377     }
   1378 
   1379     if (!PACKET_copy_bytes(&cookiepkt, s->d1->cookie, cookie_len)) {
   1380         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   1381         return MSG_PROCESS_ERROR;
   1382     }
   1383     s->d1->cookie_len = cookie_len;
   1384 
   1385     return MSG_PROCESS_FINISHED_READING;
   1386 }
   1387 
   1388 static int set_client_ciphersuite(SSL_CONNECTION *s,
   1389     const unsigned char *cipherchars)
   1390 {
   1391     STACK_OF(SSL_CIPHER) *sk;
   1392     const SSL_CIPHER *c;
   1393     int i;
   1394     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   1395 
   1396     c = ssl_get_cipher_by_char(s, cipherchars, 0);
   1397     if (c == NULL) {
   1398         /* unknown cipher */
   1399         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_UNKNOWN_CIPHER_RETURNED);
   1400         return 0;
   1401     }
   1402     /*
   1403      * If it is a disabled cipher we either didn't send it in client hello,
   1404      * or it's not allowed for the selected protocol. So we return an error.
   1405      */
   1406     if (ssl_cipher_disabled(s, c, SSL_SECOP_CIPHER_CHECK, 1)) {
   1407         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CIPHER_RETURNED);
   1408         return 0;
   1409     }
   1410 
   1411     sk = ssl_get_ciphers_by_id(s);
   1412     i = sk_SSL_CIPHER_find(sk, c);
   1413     if (i < 0) {
   1414         /* we did not say we would use this cipher */
   1415         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CIPHER_RETURNED);
   1416         return 0;
   1417     }
   1418 
   1419     if (SSL_CONNECTION_IS_TLS13(s) && s->s3.tmp.new_cipher != NULL
   1420         && s->s3.tmp.new_cipher->id != c->id) {
   1421         /* ServerHello selected a different ciphersuite to that in the HRR */
   1422         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CIPHER_RETURNED);
   1423         return 0;
   1424     }
   1425 
   1426     /*
   1427      * Depending on the session caching (internal/external), the cipher
   1428      * and/or cipher_id values may not be set. Make sure that cipher_id is
   1429      * set and use it for comparison.
   1430      */
   1431     if (s->session->cipher != NULL)
   1432         s->session->cipher_id = s->session->cipher->id;
   1433     if (s->hit && (s->session->cipher_id != c->id)) {
   1434         if (SSL_CONNECTION_IS_TLS13(s)) {
   1435             const EVP_MD *md = ssl_md(sctx, c->algorithm2);
   1436 
   1437             if (!ossl_assert(s->session->cipher != NULL)) {
   1438                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1439                 return 0;
   1440             }
   1441             /*
   1442              * In TLSv1.3 it is valid for the server to select a different
   1443              * ciphersuite as long as the hash is the same.
   1444              */
   1445             if (md == NULL
   1446                 || md != ssl_md(sctx, s->session->cipher->algorithm2)) {
   1447                 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
   1448                     SSL_R_CIPHERSUITE_DIGEST_HAS_CHANGED);
   1449                 return 0;
   1450             }
   1451         } else {
   1452             /*
   1453              * Prior to TLSv1.3 resuming a session always meant using the same
   1454              * ciphersuite.
   1455              */
   1456             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
   1457                 SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED);
   1458             return 0;
   1459         }
   1460     }
   1461     s->s3.tmp.new_cipher = c;
   1462 
   1463     return 1;
   1464 }
   1465 
   1466 MSG_PROCESS_RETURN tls_process_server_hello(SSL_CONNECTION *s, PACKET *pkt)
   1467 {
   1468     PACKET session_id, extpkt;
   1469     size_t session_id_len;
   1470     const unsigned char *cipherchars;
   1471     int hrr = 0;
   1472     unsigned int compression;
   1473     unsigned int sversion;
   1474     unsigned int context;
   1475     RAW_EXTENSION *extensions = NULL;
   1476     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
   1477     SSL *ussl = SSL_CONNECTION_GET_USER_SSL(s);
   1478 #ifndef OPENSSL_NO_COMP
   1479     SSL_COMP *comp;
   1480 #endif
   1481 
   1482     if (!PACKET_get_net_2(pkt, &sversion)) {
   1483         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   1484         goto err;
   1485     }
   1486 
   1487     /* load the server random */
   1488     if (s->version == TLS1_3_VERSION
   1489         && sversion == TLS1_2_VERSION
   1490         && PACKET_remaining(pkt) >= SSL3_RANDOM_SIZE
   1491         && memcmp(hrrrandom, PACKET_data(pkt), SSL3_RANDOM_SIZE) == 0) {
   1492         if (s->hello_retry_request != SSL_HRR_NONE) {
   1493             SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
   1494             goto err;
   1495         }
   1496         s->hello_retry_request = SSL_HRR_PENDING;
   1497         /* Tell the record layer that we know we're going to get TLSv1.3 */
   1498         if (!ssl_set_record_protocol_version(s, s->version)) {
   1499             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1500             goto err;
   1501         }
   1502         hrr = 1;
   1503         if (!PACKET_forward(pkt, SSL3_RANDOM_SIZE)) {
   1504             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   1505             goto err;
   1506         }
   1507     } else {
   1508         if (!PACKET_copy_bytes(pkt, s->s3.server_random, SSL3_RANDOM_SIZE)) {
   1509             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   1510             goto err;
   1511         }
   1512     }
   1513 
   1514     /* Get the session-id. */
   1515     if (!PACKET_get_length_prefixed_1(pkt, &session_id)) {
   1516         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   1517         goto err;
   1518     }
   1519     session_id_len = PACKET_remaining(&session_id);
   1520     if (session_id_len > sizeof(s->session->session_id)
   1521         || session_id_len > SSL3_SESSION_ID_SIZE) {
   1522         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_SSL3_SESSION_ID_TOO_LONG);
   1523         goto err;
   1524     }
   1525 
   1526     if (!PACKET_get_bytes(pkt, &cipherchars, TLS_CIPHER_LEN)) {
   1527         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   1528         goto err;
   1529     }
   1530 
   1531     if (!PACKET_get_1(pkt, &compression)) {
   1532         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   1533         goto err;
   1534     }
   1535 
   1536     /* TLS extensions */
   1537     if (PACKET_remaining(pkt) == 0 && !hrr) {
   1538         PACKET_null_init(&extpkt);
   1539     } else if (!PACKET_as_length_prefixed_2(pkt, &extpkt)
   1540         || PACKET_remaining(pkt) != 0) {
   1541         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
   1542         goto err;
   1543     }
   1544 
   1545     if (!hrr) {
   1546         if (!tls_collect_extensions(s, &extpkt,
   1547                 SSL_EXT_TLS1_2_SERVER_HELLO
   1548                     | SSL_EXT_TLS1_3_SERVER_HELLO,
   1549                 &extensions, NULL, 1)) {
   1550             /* SSLfatal() already called */
   1551             goto err;
   1552         }
   1553 
   1554         if (!ssl_choose_client_version(s, sversion, extensions)) {
   1555             /* SSLfatal() already called */
   1556             goto err;
   1557         }
   1558     }
   1559 
   1560     if (SSL_CONNECTION_IS_TLS13(s) || hrr) {
   1561         if (compression != 0) {
   1562             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
   1563                 SSL_R_INVALID_COMPRESSION_ALGORITHM);
   1564             goto err;
   1565         }
   1566 
   1567         if (session_id_len != s->tmp_session_id_len
   1568             || memcmp(PACKET_data(&session_id), s->tmp_session_id,
   1569                    session_id_len)
   1570                 != 0) {
   1571             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_INVALID_SESSION_ID);
   1572             goto err;
   1573         }
   1574     }
   1575 
   1576     if (hrr) {
   1577         if (!set_client_ciphersuite(s, cipherchars)) {
   1578             /* SSLfatal() already called */
   1579             goto err;
   1580         }
   1581 
   1582         return tls_process_as_hello_retry_request(s, &extpkt);
   1583     }
   1584 
   1585     /*
   1586      * Now we have chosen the version we need to check again that the extensions
   1587      * are appropriate for this version.
   1588      */
   1589     context = SSL_CONNECTION_IS_TLS13(s) ? SSL_EXT_TLS1_3_SERVER_HELLO
   1590                                          : SSL_EXT_TLS1_2_SERVER_HELLO;
   1591     if (!tls_validate_all_contexts(s, context, extensions)) {
   1592         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_EXTENSION);
   1593         goto err;
   1594     }
   1595 
   1596     s->hit = 0;
   1597 
   1598     if (SSL_CONNECTION_IS_TLS13(s)) {
   1599         /*
   1600          * In TLSv1.3 a ServerHello message signals a key change so the end of
   1601          * the message must be on a record boundary.
   1602          */
   1603         if (RECORD_LAYER_processed_read_pending(&s->rlayer)) {
   1604             SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
   1605                 SSL_R_NOT_ON_RECORD_BOUNDARY);
   1606             goto err;
   1607         }
   1608 
   1609         /* This will set s->hit if we are resuming */
   1610         if (!tls_parse_extension(s, TLSEXT_IDX_psk,
   1611                 SSL_EXT_TLS1_3_SERVER_HELLO,
   1612                 extensions, NULL, 0)) {
   1613             /* SSLfatal() already called */
   1614             goto err;
   1615         }
   1616     } else {
   1617         /*
   1618          * Check if we can resume the session based on external pre-shared
   1619          * secret. EAP-FAST (RFC 4851) supports two types of session resumption.
   1620          * Resumption based on server-side state works with session IDs.
   1621          * Resumption based on pre-shared Protected Access Credentials (PACs)
   1622          * works by overriding the SessionTicket extension at the application
   1623          * layer, and does not send a session ID. (We do not know whether
   1624          * EAP-FAST servers would honour the session ID.) Therefore, the session
   1625          * ID alone is not a reliable indicator of session resumption, so we
   1626          * first check if we can resume, and later peek at the next handshake
   1627          * message to see if the server wants to resume.
   1628          */
   1629         if (s->version >= TLS1_VERSION
   1630             && s->ext.session_secret_cb != NULL && s->session->ext.tick) {
   1631             const SSL_CIPHER *pref_cipher = NULL;
   1632             /*
   1633              * s->session->master_key_length is a size_t, but this is an int for
   1634              * backwards compat reasons
   1635              */
   1636             int master_key_length;
   1637 
   1638             master_key_length = sizeof(s->session->master_key);
   1639             if (s->ext.session_secret_cb(ussl, s->session->master_key,
   1640                     &master_key_length,
   1641                     NULL, &pref_cipher,
   1642                     s->ext.session_secret_cb_arg)
   1643                 && master_key_length > 0) {
   1644                 s->session->master_key_length = master_key_length;
   1645                 s->session->cipher = pref_cipher ? pref_cipher : ssl_get_cipher_by_char(s, cipherchars, 0);
   1646             } else {
   1647                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1648                 goto err;
   1649             }
   1650         }
   1651 
   1652         if (session_id_len != 0
   1653             && session_id_len == s->session->session_id_length
   1654             && memcmp(PACKET_data(&session_id), s->session->session_id,
   1655                    session_id_len)
   1656                 == 0)
   1657             s->hit = 1;
   1658     }
   1659 
   1660     if (s->hit) {
   1661         if (s->sid_ctx_length != s->session->sid_ctx_length
   1662             || memcmp(s->session->sid_ctx, s->sid_ctx, s->sid_ctx_length)) {
   1663             /* actually a client application bug */
   1664             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
   1665                 SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
   1666             goto err;
   1667         }
   1668     } else {
   1669         /*
   1670          * If we were trying for session-id reuse but the server
   1671          * didn't resume, make a new SSL_SESSION.
   1672          * In the case of EAP-FAST and PAC, we do not send a session ID,
   1673          * so the PAC-based session secret is always preserved. It'll be
   1674          * overwritten if the server refuses resumption.
   1675          */
   1676         if (s->session->session_id_length > 0) {
   1677             ssl_tsan_counter(s->session_ctx, &s->session_ctx->stats.sess_miss);
   1678             if (!ssl_get_new_session(s, 0)) {
   1679                 /* SSLfatal() already called */
   1680                 goto err;
   1681             }
   1682         }
   1683 
   1684         s->session->ssl_version = s->version;
   1685         /*
   1686          * In TLSv1.2 and below we save the session id we were sent so we can
   1687          * resume it later. In TLSv1.3 the session id we were sent is just an
   1688          * echo of what we originally sent in the ClientHello and should not be
   1689          * used for resumption.
   1690          */
   1691         if (!SSL_CONNECTION_IS_TLS13(s)) {
   1692             s->session->session_id_length = session_id_len;
   1693             /* session_id_len could be 0 */
   1694             if (session_id_len > 0)
   1695                 memcpy(s->session->session_id, PACKET_data(&session_id),
   1696                     session_id_len);
   1697         }
   1698     }
   1699 
   1700     /* Session version and negotiated protocol version should match */
   1701     if (s->version != s->session->ssl_version) {
   1702         SSLfatal(s, SSL_AD_PROTOCOL_VERSION,
   1703             SSL_R_SSL_SESSION_VERSION_MISMATCH);
   1704         goto err;
   1705     }
   1706     /*
   1707      * Now that we know the version, update the check to see if it's an allowed
   1708      * version.
   1709      */
   1710     s->s3.tmp.min_ver = s->version;
   1711     s->s3.tmp.max_ver = s->version;
   1712 
   1713     if (!set_client_ciphersuite(s, cipherchars)) {
   1714         /* SSLfatal() already called */
   1715         goto err;
   1716     }
   1717 
   1718 #ifdef OPENSSL_NO_COMP
   1719     if (compression != 0) {
   1720         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
   1721             SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
   1722         goto err;
   1723     }
   1724     /*
   1725      * If compression is disabled we'd better not try to resume a session
   1726      * using compression.
   1727      */
   1728     if (s->session->compress_meth != 0) {
   1729         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_INCONSISTENT_COMPRESSION);
   1730         goto err;
   1731     }
   1732 #else
   1733     if (s->hit && compression != s->session->compress_meth) {
   1734         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
   1735             SSL_R_OLD_SESSION_COMPRESSION_ALGORITHM_NOT_RETURNED);
   1736         goto err;
   1737     }
   1738     if (compression == 0)
   1739         comp = NULL;
   1740     else if (!ssl_allow_compression(s)) {
   1741         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_COMPRESSION_DISABLED);
   1742         goto err;
   1743     } else {
   1744         comp = ssl3_comp_find(SSL_CONNECTION_GET_CTX(s)->comp_methods,
   1745             compression);
   1746     }
   1747 
   1748     if (compression != 0 && comp == NULL) {
   1749         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
   1750             SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
   1751         goto err;
   1752     } else {
   1753         s->s3.tmp.new_compression = comp;
   1754     }
   1755 #endif
   1756 
   1757     if (!tls_parse_all_extensions(s, context, extensions, NULL, 0, 1)) {
   1758         /* SSLfatal() already called */
   1759         goto err;
   1760     }
   1761 
   1762 #ifndef OPENSSL_NO_SCTP
   1763     if (SSL_CONNECTION_IS_DTLS(s) && s->hit) {
   1764         unsigned char sctpauthkey[64];
   1765         char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
   1766         size_t labellen;
   1767 
   1768         /*
   1769          * Add new shared key for SCTP-Auth, will be ignored if
   1770          * no SCTP used.
   1771          */
   1772         memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
   1773             sizeof(DTLS1_SCTP_AUTH_LABEL));
   1774 
   1775         /* Don't include the terminating zero. */
   1776         labellen = sizeof(labelbuffer) - 1;
   1777         if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
   1778             labellen += 1;
   1779 
   1780         if (SSL_export_keying_material(ssl, sctpauthkey,
   1781                 sizeof(sctpauthkey),
   1782                 labelbuffer,
   1783                 labellen, NULL, 0, 0)
   1784             <= 0) {
   1785             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   1786             goto err;
   1787         }
   1788 
   1789         BIO_ctrl(SSL_get_wbio(ssl),
   1790             BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
   1791             sizeof(sctpauthkey), sctpauthkey);
   1792     }
   1793 #endif
   1794 
   1795     /*
   1796      * In TLSv1.3 we have some post-processing to change cipher state, otherwise
   1797      * we're done with this message
   1798      */
   1799     if (SSL_CONNECTION_IS_TLS13(s)) {
   1800         if (!ssl->method->ssl3_enc->setup_key_block(s)
   1801             || !tls13_store_handshake_traffic_hash(s)) {
   1802             /* SSLfatal() already called */
   1803             goto err;
   1804         }
   1805         /*
   1806          * If we're not doing early-data and we're not going to send a dummy CCS
   1807          * (i.e. no middlebox compat mode) then we can change the write keys
   1808          * immediately. Otherwise we have to defer this until after all possible
   1809          * early data is written. We could just always defer until the last
   1810          * moment except QUIC needs it done at the same time as the read keys
   1811          * are changed. Since QUIC doesn't do TLS early data or need middlebox
   1812          * compat this doesn't cause a problem.
   1813          */
   1814         if (SSL_IS_QUIC_HANDSHAKE(s)
   1815             || (s->early_data_state == SSL_EARLY_DATA_NONE
   1816                 && (s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) == 0)) {
   1817             if (!ssl->method->ssl3_enc->change_cipher_state(s,
   1818                     SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
   1819                 /* SSLfatal() already called */
   1820                 goto err;
   1821             }
   1822         }
   1823         if (!ssl->method->ssl3_enc->change_cipher_state(s,
   1824                 SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_READ)) {
   1825             /* SSLfatal() already called */
   1826             goto err;
   1827         }
   1828     }
   1829 
   1830     OPENSSL_free(extensions);
   1831     return MSG_PROCESS_CONTINUE_READING;
   1832 err:
   1833     OPENSSL_free(extensions);
   1834     return MSG_PROCESS_ERROR;
   1835 }
   1836 
   1837 static MSG_PROCESS_RETURN tls_process_as_hello_retry_request(SSL_CONNECTION *s,
   1838     PACKET *extpkt)
   1839 {
   1840     RAW_EXTENSION *extensions = NULL;
   1841 
   1842     /*
   1843      * If we were sending early_data then any alerts should not be sent using
   1844      * the old wrlmethod.
   1845      */
   1846     if (s->early_data_state == SSL_EARLY_DATA_FINISHED_WRITING
   1847         && !ssl_set_new_record_layer(s,
   1848             TLS_ANY_VERSION,
   1849             OSSL_RECORD_DIRECTION_WRITE,
   1850             OSSL_RECORD_PROTECTION_LEVEL_NONE,
   1851             NULL, 0, NULL, 0, NULL, 0, NULL, 0,
   1852             NULL, 0, NID_undef, NULL, NULL, NULL)) {
   1853         /* SSLfatal already called */
   1854         goto err;
   1855     }
   1856     /* We are definitely going to be using TLSv1.3 */
   1857     s->rlayer.wrlmethod->set_protocol_version(s->rlayer.wrl, TLS1_3_VERSION);
   1858 
   1859     if (!tls_collect_extensions(s, extpkt, SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST,
   1860             &extensions, NULL, 1)
   1861         || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST,
   1862             extensions, NULL, 0, 1)) {
   1863         /* SSLfatal() already called */
   1864         goto err;
   1865     }
   1866 
   1867     OPENSSL_free(extensions);
   1868     extensions = NULL;
   1869 
   1870     if (s->ext.tls13_cookie_len == 0 && s->s3.tmp.pkey != NULL) {
   1871         /*
   1872          * We didn't receive a cookie or a new key_share so the next
   1873          * ClientHello will not change
   1874          */
   1875         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_NO_CHANGE_FOLLOWING_HRR);
   1876         goto err;
   1877     }
   1878 
   1879     /*
   1880      * Re-initialise the Transcript Hash. We're going to prepopulate it with
   1881      * a synthetic message_hash in place of ClientHello1.
   1882      */
   1883     if (!create_synthetic_message_hash(s, NULL, 0, NULL, 0)) {
   1884         /* SSLfatal() already called */
   1885         goto err;
   1886     }
   1887 
   1888     /*
   1889      * Add this message to the Transcript Hash. Normally this is done
   1890      * automatically prior to the message processing stage. However due to the
   1891      * need to create the synthetic message hash, we defer that step until now
   1892      * for HRR messages.
   1893      */
   1894     if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
   1895             s->init_num + SSL3_HM_HEADER_LENGTH)) {
   1896         /* SSLfatal() already called */
   1897         goto err;
   1898     }
   1899 
   1900     return MSG_PROCESS_FINISHED_READING;
   1901 err:
   1902     OPENSSL_free(extensions);
   1903     return MSG_PROCESS_ERROR;
   1904 }
   1905 
   1906 MSG_PROCESS_RETURN tls_process_server_rpk(SSL_CONNECTION *sc, PACKET *pkt)
   1907 {
   1908     EVP_PKEY *peer_rpk = NULL;
   1909 
   1910     if (!tls_process_rpk(sc, pkt, &peer_rpk)) {
   1911         /* SSLfatal() already called */
   1912         return MSG_PROCESS_ERROR;
   1913     }
   1914 
   1915     if (peer_rpk == NULL) {
   1916         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_CERTIFICATE);
   1917         return MSG_PROCESS_ERROR;
   1918     }
   1919 
   1920     EVP_PKEY_free(sc->session->peer_rpk);
   1921     sc->session->peer_rpk = peer_rpk;
   1922 
   1923     return MSG_PROCESS_CONTINUE_PROCESSING;
   1924 }
   1925 
   1926 static WORK_STATE tls_post_process_server_rpk(SSL_CONNECTION *sc,
   1927     WORK_STATE wst)
   1928 {
   1929     size_t certidx;
   1930     const SSL_CERT_LOOKUP *clu;
   1931     int v_ok;
   1932 
   1933     if (sc->session->peer_rpk == NULL) {
   1934         SSLfatal(sc, SSL_AD_ILLEGAL_PARAMETER,
   1935             SSL_R_INVALID_RAW_PUBLIC_KEY);
   1936         return WORK_ERROR;
   1937     }
   1938 
   1939     if (sc->rwstate == SSL_RETRY_VERIFY)
   1940         sc->rwstate = SSL_NOTHING;
   1941 
   1942     ERR_set_mark();
   1943     v_ok = ssl_verify_rpk(sc, sc->session->peer_rpk);
   1944     if (v_ok <= 0 && sc->verify_mode != SSL_VERIFY_NONE) {
   1945         ERR_clear_last_mark();
   1946         SSLfatal(sc, ssl_x509err2alert(sc->verify_result),
   1947             SSL_R_CERTIFICATE_VERIFY_FAILED);
   1948         return WORK_ERROR;
   1949     }
   1950     ERR_pop_to_mark(); /* but we keep s->verify_result */
   1951     if (v_ok > 0 && sc->rwstate == SSL_RETRY_VERIFY) {
   1952         return WORK_MORE_A;
   1953     }
   1954 
   1955     if ((clu = ssl_cert_lookup_by_pkey(sc->session->peer_rpk, &certidx,
   1956              SSL_CONNECTION_GET_CTX(sc)))
   1957         == NULL) {
   1958         SSLfatal(sc, SSL_AD_ILLEGAL_PARAMETER, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
   1959         return WORK_ERROR;
   1960     }
   1961 
   1962     /*
   1963      * Check certificate type is consistent with ciphersuite. For TLS 1.3
   1964      * skip check since TLS 1.3 ciphersuites can be used with any certificate
   1965      * type.
   1966      */
   1967     if (!SSL_CONNECTION_IS_TLS13(sc)) {
   1968         if ((clu->amask & sc->s3.tmp.new_cipher->algorithm_auth) == 0) {
   1969             SSLfatal(sc, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_RPK_TYPE);
   1970             return WORK_ERROR;
   1971         }
   1972     }
   1973 
   1974     /* Ensure there is no peer/peer_chain */
   1975     X509_free(sc->session->peer);
   1976     sc->session->peer = NULL;
   1977     sk_X509_pop_free(sc->session->peer_chain, X509_free);
   1978     sc->session->peer_chain = NULL;
   1979     sc->session->verify_result = sc->verify_result;
   1980 
   1981     /* Save the current hash state for when we receive the CertificateVerify */
   1982     if (SSL_CONNECTION_IS_TLS13(sc)
   1983         && !ssl_handshake_hash(sc, sc->cert_verify_hash,
   1984             sizeof(sc->cert_verify_hash),
   1985             &sc->cert_verify_hash_len)) {
   1986         /* SSLfatal() already called */
   1987         return WORK_ERROR;
   1988     }
   1989 
   1990     return WORK_FINISHED_CONTINUE;
   1991 }
   1992 
   1993 /* prepare server cert verification by setting s->session->peer_chain from pkt */
   1994 MSG_PROCESS_RETURN tls_process_server_certificate(SSL_CONNECTION *s,
   1995     PACKET *pkt)
   1996 {
   1997     unsigned long cert_list_len, cert_len;
   1998     X509 *x = NULL;
   1999     const unsigned char *certstart, *certbytes;
   2000     size_t chainidx;
   2001     unsigned int context = 0;
   2002     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   2003 
   2004     if (s->ext.server_cert_type == TLSEXT_cert_type_rpk)
   2005         return tls_process_server_rpk(s, pkt);
   2006     if (s->ext.server_cert_type != TLSEXT_cert_type_x509) {
   2007         SSLfatal(s, SSL_AD_UNSUPPORTED_CERTIFICATE,
   2008             SSL_R_UNKNOWN_CERTIFICATE_TYPE);
   2009         goto err;
   2010     }
   2011 
   2012     if ((s->session->peer_chain = sk_X509_new_null()) == NULL) {
   2013         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   2014         goto err;
   2015     }
   2016 
   2017     if ((SSL_CONNECTION_IS_TLS13(s) && !PACKET_get_1(pkt, &context))
   2018         || context != 0
   2019         || !PACKET_get_net_3(pkt, &cert_list_len)
   2020         || PACKET_remaining(pkt) != cert_list_len
   2021         || PACKET_remaining(pkt) == 0) {
   2022         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2023         goto err;
   2024     }
   2025     for (chainidx = 0; PACKET_remaining(pkt); chainidx++) {
   2026         if (!PACKET_get_net_3(pkt, &cert_len)
   2027             || !PACKET_get_bytes(pkt, &certbytes, cert_len)) {
   2028             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_CERT_LENGTH_MISMATCH);
   2029             goto err;
   2030         }
   2031 
   2032         certstart = certbytes;
   2033         x = X509_new_ex(sctx->libctx, sctx->propq);
   2034         if (x == NULL) {
   2035             SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_ASN1_LIB);
   2036             goto err;
   2037         }
   2038         if (d2i_X509(&x, (const unsigned char **)&certbytes,
   2039                 cert_len)
   2040             == NULL) {
   2041             SSLfatal(s, SSL_AD_BAD_CERTIFICATE, ERR_R_ASN1_LIB);
   2042             goto err;
   2043         }
   2044 
   2045         if (certbytes != (certstart + cert_len)) {
   2046             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_CERT_LENGTH_MISMATCH);
   2047             goto err;
   2048         }
   2049 
   2050         if (SSL_CONNECTION_IS_TLS13(s)) {
   2051             RAW_EXTENSION *rawexts = NULL;
   2052             PACKET extensions;
   2053 
   2054             if (!PACKET_get_length_prefixed_2(pkt, &extensions)) {
   2055                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
   2056                 goto err;
   2057             }
   2058             if (!tls_collect_extensions(s, &extensions,
   2059                     SSL_EXT_TLS1_3_CERTIFICATE, &rawexts,
   2060                     NULL, chainidx == 0)
   2061                 || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE,
   2062                     rawexts, x, chainidx,
   2063                     PACKET_remaining(pkt) == 0)) {
   2064                 OPENSSL_free(rawexts);
   2065                 /* SSLfatal already called */
   2066                 goto err;
   2067             }
   2068             OPENSSL_free(rawexts);
   2069         }
   2070 
   2071         if (!sk_X509_push(s->session->peer_chain, x)) {
   2072             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   2073             goto err;
   2074         }
   2075         x = NULL;
   2076     }
   2077     return MSG_PROCESS_CONTINUE_PROCESSING;
   2078 
   2079 err:
   2080     X509_free(x);
   2081     OSSL_STACK_OF_X509_free(s->session->peer_chain);
   2082     s->session->peer_chain = NULL;
   2083     return MSG_PROCESS_ERROR;
   2084 }
   2085 
   2086 /*
   2087  * Verify the s->session->peer_chain and check server cert type.
   2088  * On success set s->session->peer and s->session->verify_result.
   2089  * Else the peer certificate verification callback may request retry.
   2090  */
   2091 WORK_STATE tls_post_process_server_certificate(SSL_CONNECTION *s,
   2092     WORK_STATE wst)
   2093 {
   2094     X509 *x;
   2095     EVP_PKEY *pkey = NULL;
   2096     const SSL_CERT_LOOKUP *clu;
   2097     size_t certidx;
   2098     int i;
   2099 
   2100     if (s->ext.server_cert_type == TLSEXT_cert_type_rpk)
   2101         return tls_post_process_server_rpk(s, wst);
   2102 
   2103     if (s->rwstate == SSL_RETRY_VERIFY)
   2104         s->rwstate = SSL_NOTHING;
   2105 
   2106     /*
   2107      * The documented interface is that SSL_VERIFY_PEER should be set in order
   2108      * for client side verification of the server certificate to take place.
   2109      * However, historically the code has only checked that *any* flag is set
   2110      * to cause server verification to take place. Use of the other flags makes
   2111      * no sense in client mode. An attempt to clean up the semantics was
   2112      * reverted because at least one application *only* set
   2113      * SSL_VERIFY_FAIL_IF_NO_PEER_CERT. Prior to the clean up this still caused
   2114      * server verification to take place, after the clean up it silently did
   2115      * nothing. SSL_CTX_set_verify()/SSL_set_verify() cannot validate the flags
   2116      * sent to them because they are void functions. Therefore, we now use the
   2117      * (less clean) historic behaviour of performing validation if any flag is
   2118      * set. The *documented* interface remains the same.
   2119      */
   2120     ERR_set_mark();
   2121     i = ssl_verify_cert_chain(s, s->session->peer_chain);
   2122     if (i <= 0 && s->verify_mode != SSL_VERIFY_NONE) {
   2123         ERR_clear_last_mark();
   2124         SSLfatal(s, ssl_x509err2alert(s->verify_result),
   2125             SSL_R_CERTIFICATE_VERIFY_FAILED);
   2126         return WORK_ERROR;
   2127     }
   2128     ERR_pop_to_mark(); /* but we keep s->verify_result */
   2129     if (i > 0 && s->rwstate == SSL_RETRY_VERIFY)
   2130         return WORK_MORE_A;
   2131 
   2132     /*
   2133      * Inconsistency alert: cert_chain does include the peer's certificate,
   2134      * which we don't include in statem_srvr.c
   2135      */
   2136     x = sk_X509_value(s->session->peer_chain, 0);
   2137 
   2138     pkey = X509_get0_pubkey(x);
   2139 
   2140     if (pkey == NULL || EVP_PKEY_missing_parameters(pkey)) {
   2141         SSLfatal(s, SSL_AD_INTERNAL_ERROR,
   2142             SSL_R_UNABLE_TO_FIND_PUBLIC_KEY_PARAMETERS);
   2143         return WORK_ERROR;
   2144     }
   2145 
   2146     if ((clu = ssl_cert_lookup_by_pkey(pkey, &certidx,
   2147              SSL_CONNECTION_GET_CTX(s)))
   2148         == NULL) {
   2149         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
   2150         return WORK_ERROR;
   2151     }
   2152     /*
   2153      * Check certificate type is consistent with ciphersuite. For TLS 1.3
   2154      * skip check since TLS 1.3 ciphersuites can be used with any certificate
   2155      * type.
   2156      */
   2157     if (!SSL_CONNECTION_IS_TLS13(s)) {
   2158         if ((clu->amask & s->s3.tmp.new_cipher->algorithm_auth) == 0) {
   2159             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CERTIFICATE_TYPE);
   2160             return WORK_ERROR;
   2161         }
   2162     }
   2163 
   2164     if (!X509_up_ref(x)) {
   2165         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   2166         return WORK_ERROR;
   2167     }
   2168 
   2169     X509_free(s->session->peer);
   2170     s->session->peer = x;
   2171     s->session->verify_result = s->verify_result;
   2172     /* Ensure there is no RPK */
   2173     EVP_PKEY_free(s->session->peer_rpk);
   2174     s->session->peer_rpk = NULL;
   2175 
   2176     /* Save the current hash state for when we receive the CertificateVerify */
   2177     if (SSL_CONNECTION_IS_TLS13(s)
   2178         && !ssl_handshake_hash(s, s->cert_verify_hash,
   2179             sizeof(s->cert_verify_hash),
   2180             &s->cert_verify_hash_len)) {
   2181         /* SSLfatal() already called */;
   2182         return WORK_ERROR;
   2183     }
   2184     return WORK_FINISHED_CONTINUE;
   2185 }
   2186 
   2187 #ifndef OPENSSL_NO_COMP_ALG
   2188 MSG_PROCESS_RETURN tls_process_server_compressed_certificate(SSL_CONNECTION *sc, PACKET *pkt)
   2189 {
   2190     MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;
   2191     PACKET tmppkt;
   2192     BUF_MEM *buf = BUF_MEM_new();
   2193 
   2194     if (tls13_process_compressed_certificate(sc, pkt, &tmppkt, buf) != MSG_PROCESS_ERROR)
   2195         ret = tls_process_server_certificate(sc, &tmppkt);
   2196 
   2197     BUF_MEM_free(buf);
   2198     return ret;
   2199 }
   2200 #endif
   2201 
   2202 static int tls_process_ske_psk_preamble(SSL_CONNECTION *s, PACKET *pkt)
   2203 {
   2204 #ifndef OPENSSL_NO_PSK
   2205     PACKET psk_identity_hint;
   2206 
   2207     /* PSK ciphersuites are preceded by an identity hint */
   2208 
   2209     if (!PACKET_get_length_prefixed_2(pkt, &psk_identity_hint)) {
   2210         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2211         return 0;
   2212     }
   2213 
   2214     /*
   2215      * Store PSK identity hint for later use, hint is used in
   2216      * tls_construct_client_key_exchange.  Assume that the maximum length of
   2217      * a PSK identity hint can be as long as the maximum length of a PSK
   2218      * identity.
   2219      */
   2220     if (PACKET_remaining(&psk_identity_hint) > PSK_MAX_IDENTITY_LEN) {
   2221         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_DATA_LENGTH_TOO_LONG);
   2222         return 0;
   2223     }
   2224 
   2225     if (PACKET_remaining(&psk_identity_hint) == 0) {
   2226         OPENSSL_free(s->session->psk_identity_hint);
   2227         s->session->psk_identity_hint = NULL;
   2228     } else if (!PACKET_strndup(&psk_identity_hint,
   2229                    &s->session->psk_identity_hint)) {
   2230         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   2231         return 0;
   2232     }
   2233 
   2234     return 1;
   2235 #else
   2236     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   2237     return 0;
   2238 #endif
   2239 }
   2240 
   2241 static int tls_process_ske_srp(SSL_CONNECTION *s, PACKET *pkt, EVP_PKEY **pkey)
   2242 {
   2243 #ifndef OPENSSL_NO_SRP
   2244     PACKET prime, generator, salt, server_pub;
   2245 
   2246     if (!PACKET_get_length_prefixed_2(pkt, &prime)
   2247         || !PACKET_get_length_prefixed_2(pkt, &generator)
   2248         || !PACKET_get_length_prefixed_1(pkt, &salt)
   2249         || !PACKET_get_length_prefixed_2(pkt, &server_pub)) {
   2250         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2251         return 0;
   2252     }
   2253 
   2254     if ((s->srp_ctx.N = BN_bin2bn(PACKET_data(&prime),
   2255              (int)PACKET_remaining(&prime), NULL))
   2256             == NULL
   2257         || (s->srp_ctx.g = BN_bin2bn(PACKET_data(&generator),
   2258                 (int)PACKET_remaining(&generator), NULL))
   2259             == NULL
   2260         || (s->srp_ctx.s = BN_bin2bn(PACKET_data(&salt),
   2261                 (int)PACKET_remaining(&salt), NULL))
   2262             == NULL
   2263         || (s->srp_ctx.B = BN_bin2bn(PACKET_data(&server_pub),
   2264                 (int)PACKET_remaining(&server_pub), NULL))
   2265             == NULL) {
   2266         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BN_LIB);
   2267         return 0;
   2268     }
   2269 
   2270     if (!srp_verify_server_param(s)) {
   2271         /* SSLfatal() already called */
   2272         return 0;
   2273     }
   2274 
   2275     /* We must check if there is a certificate */
   2276     if (s->s3.tmp.new_cipher->algorithm_auth & (SSL_aRSA | SSL_aDSS))
   2277         *pkey = tls_get_peer_pkey(s);
   2278 
   2279     return 1;
   2280 #else
   2281     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   2282     return 0;
   2283 #endif
   2284 }
   2285 
   2286 static int tls_process_ske_dhe(SSL_CONNECTION *s, PACKET *pkt, EVP_PKEY **pkey)
   2287 {
   2288     PACKET prime, generator, pub_key;
   2289     EVP_PKEY *peer_tmp = NULL;
   2290     BIGNUM *p = NULL, *g = NULL, *bnpub_key = NULL;
   2291     EVP_PKEY_CTX *pctx = NULL;
   2292     OSSL_PARAM *params = NULL;
   2293     OSSL_PARAM_BLD *tmpl = NULL;
   2294     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   2295     int ret = 0;
   2296 
   2297     if (!PACKET_get_length_prefixed_2(pkt, &prime)
   2298         || !PACKET_get_length_prefixed_2(pkt, &generator)
   2299         || !PACKET_get_length_prefixed_2(pkt, &pub_key)) {
   2300         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2301         return 0;
   2302     }
   2303 
   2304     p = BN_bin2bn(PACKET_data(&prime), (int)PACKET_remaining(&prime), NULL);
   2305     g = BN_bin2bn(PACKET_data(&generator), (int)PACKET_remaining(&generator),
   2306         NULL);
   2307     bnpub_key = BN_bin2bn(PACKET_data(&pub_key),
   2308         (int)PACKET_remaining(&pub_key), NULL);
   2309     if (p == NULL || g == NULL || bnpub_key == NULL) {
   2310         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BN_LIB);
   2311         goto err;
   2312     }
   2313 
   2314     tmpl = OSSL_PARAM_BLD_new();
   2315     if (tmpl == NULL
   2316         || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_P, p)
   2317         || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_G, g)
   2318         || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_PUB_KEY,
   2319             bnpub_key)
   2320         || (params = OSSL_PARAM_BLD_to_param(tmpl)) == NULL) {
   2321         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   2322         goto err;
   2323     }
   2324 
   2325     pctx = EVP_PKEY_CTX_new_from_name(sctx->libctx, "DH", sctx->propq);
   2326     if (pctx == NULL) {
   2327         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   2328         goto err;
   2329     }
   2330     if (EVP_PKEY_fromdata_init(pctx) <= 0
   2331         || EVP_PKEY_fromdata(pctx, &peer_tmp, EVP_PKEY_KEYPAIR, params) <= 0) {
   2332         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_DH_VALUE);
   2333         goto err;
   2334     }
   2335 
   2336     EVP_PKEY_CTX_free(pctx);
   2337     pctx = EVP_PKEY_CTX_new_from_pkey(sctx->libctx, peer_tmp, sctx->propq);
   2338     if (pctx == NULL
   2339         /*
   2340          * EVP_PKEY_param_check() will verify that the DH params are using
   2341          * a safe prime. In this context, because we're using ephemeral DH,
   2342          * we're ok with it not being a safe prime.
   2343          * EVP_PKEY_param_check_quick() skips the safe prime check.
   2344          */
   2345         || EVP_PKEY_param_check_quick(pctx) != 1
   2346         || EVP_PKEY_public_check(pctx) != 1) {
   2347         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_DH_VALUE);
   2348         goto err;
   2349     }
   2350 
   2351     if (!ssl_security(s, SSL_SECOP_TMP_DH,
   2352             EVP_PKEY_get_security_bits(peer_tmp),
   2353             0, peer_tmp)) {
   2354         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_DH_KEY_TOO_SMALL);
   2355         goto err;
   2356     }
   2357 
   2358     s->s3.peer_tmp = peer_tmp;
   2359     peer_tmp = NULL;
   2360 
   2361     /*
   2362      * FIXME: This makes assumptions about which ciphersuites come with
   2363      * public keys. We should have a less ad-hoc way of doing this
   2364      */
   2365     if (s->s3.tmp.new_cipher->algorithm_auth & (SSL_aRSA | SSL_aDSS))
   2366         *pkey = tls_get_peer_pkey(s);
   2367     /* else anonymous DH, so no certificate or pkey. */
   2368 
   2369     ret = 1;
   2370 
   2371 err:
   2372     OSSL_PARAM_BLD_free(tmpl);
   2373     OSSL_PARAM_free(params);
   2374     EVP_PKEY_free(peer_tmp);
   2375     EVP_PKEY_CTX_free(pctx);
   2376     BN_free(p);
   2377     BN_free(g);
   2378     BN_free(bnpub_key);
   2379 
   2380     return ret;
   2381 }
   2382 
   2383 static int tls_process_ske_ecdhe(SSL_CONNECTION *s, PACKET *pkt, EVP_PKEY **pkey)
   2384 {
   2385     PACKET encoded_pt;
   2386     unsigned int curve_type, curve_id;
   2387 
   2388     /*
   2389      * Extract elliptic curve parameters and the server's ephemeral ECDH
   2390      * public key. We only support named (not generic) curves and
   2391      * ECParameters in this case is just three bytes.
   2392      */
   2393     if (!PACKET_get_1(pkt, &curve_type) || !PACKET_get_net_2(pkt, &curve_id)) {
   2394         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
   2395         return 0;
   2396     }
   2397     /*
   2398      * Check curve is named curve type and one of our preferences, if not
   2399      * server has sent an invalid curve.
   2400      */
   2401     if (curve_type != NAMED_CURVE_TYPE
   2402         || !tls1_check_group_id(s, curve_id, 1)) {
   2403         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_WRONG_CURVE);
   2404         return 0;
   2405     }
   2406 
   2407     if ((s->s3.peer_tmp = ssl_generate_param_group(s, curve_id)) == NULL) {
   2408         SSLfatal(s, SSL_AD_INTERNAL_ERROR,
   2409             SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS);
   2410         return 0;
   2411     }
   2412 
   2413     if (!PACKET_get_length_prefixed_1(pkt, &encoded_pt)) {
   2414         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2415         return 0;
   2416     }
   2417 
   2418     if (EVP_PKEY_set1_encoded_public_key(s->s3.peer_tmp,
   2419             PACKET_data(&encoded_pt),
   2420             PACKET_remaining(&encoded_pt))
   2421         <= 0) {
   2422         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_ECPOINT);
   2423         return 0;
   2424     }
   2425 
   2426     /*
   2427      * The ECC/TLS specification does not mention the use of DSA to sign
   2428      * ECParameters in the server key exchange message. We do support RSA
   2429      * and ECDSA.
   2430      */
   2431     if (s->s3.tmp.new_cipher->algorithm_auth & SSL_aECDSA)
   2432         *pkey = tls_get_peer_pkey(s);
   2433     else if (s->s3.tmp.new_cipher->algorithm_auth & SSL_aRSA)
   2434         *pkey = tls_get_peer_pkey(s);
   2435     /* else anonymous ECDH, so no certificate or pkey. */
   2436 
   2437     /* Cache the agreed upon group in the SSL_SESSION */
   2438     s->session->kex_group = curve_id;
   2439     return 1;
   2440 }
   2441 
   2442 MSG_PROCESS_RETURN tls_process_key_exchange(SSL_CONNECTION *s, PACKET *pkt)
   2443 {
   2444     long alg_k;
   2445     EVP_PKEY *pkey = NULL;
   2446     EVP_MD_CTX *md_ctx = NULL;
   2447     EVP_PKEY_CTX *pctx = NULL;
   2448     PACKET save_param_start, signature;
   2449     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   2450 
   2451     alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
   2452 
   2453     save_param_start = *pkt;
   2454 
   2455     EVP_PKEY_free(s->s3.peer_tmp);
   2456     s->s3.peer_tmp = NULL;
   2457 
   2458     if (alg_k & SSL_PSK) {
   2459         if (!tls_process_ske_psk_preamble(s, pkt)) {
   2460             /* SSLfatal() already called */
   2461             goto err;
   2462         }
   2463     }
   2464 
   2465     /* Nothing else to do for plain PSK or RSAPSK */
   2466     if (alg_k & (SSL_kPSK | SSL_kRSAPSK)) {
   2467     } else if (alg_k & SSL_kSRP) {
   2468         if (!tls_process_ske_srp(s, pkt, &pkey)) {
   2469             /* SSLfatal() already called */
   2470             goto err;
   2471         }
   2472     } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
   2473         if (!tls_process_ske_dhe(s, pkt, &pkey)) {
   2474             /* SSLfatal() already called */
   2475             goto err;
   2476         }
   2477     } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
   2478         if (!tls_process_ske_ecdhe(s, pkt, &pkey)) {
   2479             /* SSLfatal() already called */
   2480             goto err;
   2481         }
   2482     } else if (alg_k) {
   2483         SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE);
   2484         goto err;
   2485     }
   2486 
   2487     /* if it was signed, check the signature */
   2488     if (pkey != NULL) {
   2489         PACKET params;
   2490         const EVP_MD *md = NULL;
   2491         unsigned char *tbs;
   2492         size_t tbslen;
   2493         int rv;
   2494 
   2495         /*
   2496          * |pkt| now points to the beginning of the signature, so the difference
   2497          * equals the length of the parameters.
   2498          */
   2499         if (!PACKET_get_sub_packet(&save_param_start, &params,
   2500                 PACKET_remaining(&save_param_start) - PACKET_remaining(pkt))) {
   2501             SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_INTERNAL_ERROR);
   2502             goto err;
   2503         }
   2504 
   2505         if (SSL_USE_SIGALGS(s)) {
   2506             unsigned int sigalg;
   2507 
   2508             if (!PACKET_get_net_2(pkt, &sigalg)) {
   2509                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
   2510                 goto err;
   2511             }
   2512             if (tls12_check_peer_sigalg(s, sigalg, pkey) <= 0) {
   2513                 /* SSLfatal() already called */
   2514                 goto err;
   2515             }
   2516         } else if (!tls1_set_peer_legacy_sigalg(s, pkey)) {
   2517             SSLfatal(s, SSL_AD_INTERNAL_ERROR,
   2518                 SSL_R_LEGACY_SIGALG_DISALLOWED_OR_UNSUPPORTED);
   2519             goto err;
   2520         }
   2521 
   2522         if (!tls1_lookup_md(sctx, s->s3.tmp.peer_sigalg, &md)) {
   2523             SSLfatal(s, SSL_AD_INTERNAL_ERROR,
   2524                 SSL_R_NO_SUITABLE_DIGEST_ALGORITHM);
   2525             goto err;
   2526         }
   2527         if (SSL_USE_SIGALGS(s))
   2528             OSSL_TRACE1(TLS, "USING TLSv1.2 HASH %s\n",
   2529                 md == NULL ? "n/a" : EVP_MD_get0_name(md));
   2530 
   2531         if (!PACKET_get_length_prefixed_2(pkt, &signature)
   2532             || PACKET_remaining(pkt) != 0) {
   2533             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2534             goto err;
   2535         }
   2536 
   2537         md_ctx = EVP_MD_CTX_new();
   2538         if (md_ctx == NULL) {
   2539             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   2540             goto err;
   2541         }
   2542 
   2543         if (EVP_DigestVerifyInit_ex(md_ctx, &pctx,
   2544                 md == NULL ? NULL : EVP_MD_get0_name(md),
   2545                 sctx->libctx, sctx->propq, pkey,
   2546                 NULL)
   2547             <= 0) {
   2548             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   2549             goto err;
   2550         }
   2551         if (SSL_USE_PSS(s)) {
   2552             if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
   2553                 || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx,
   2554                        RSA_PSS_SALTLEN_DIGEST)
   2555                     <= 0) {
   2556                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   2557                 goto err;
   2558             }
   2559         }
   2560         tbslen = construct_key_exchange_tbs(s, &tbs, PACKET_data(&params),
   2561             PACKET_remaining(&params));
   2562         if (tbslen == 0) {
   2563             /* SSLfatal() already called */
   2564             goto err;
   2565         }
   2566 
   2567         rv = EVP_DigestVerify(md_ctx, PACKET_data(&signature),
   2568             PACKET_remaining(&signature), tbs, tbslen);
   2569         OPENSSL_free(tbs);
   2570         if (rv <= 0) {
   2571             SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_R_BAD_SIGNATURE);
   2572             goto err;
   2573         }
   2574         EVP_MD_CTX_free(md_ctx);
   2575         md_ctx = NULL;
   2576     } else {
   2577         /* aNULL, aSRP or PSK do not need public keys */
   2578         if (!(s->s3.tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP))
   2579             && !(alg_k & SSL_PSK)) {
   2580             /* Might be wrong key type, check it */
   2581             if (ssl3_check_cert_and_algorithm(s)) {
   2582                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_DATA);
   2583             }
   2584             /* else this shouldn't happen, SSLfatal() already called */
   2585             goto err;
   2586         }
   2587         /* still data left over */
   2588         if (PACKET_remaining(pkt) != 0) {
   2589             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_EXTRA_DATA_IN_MESSAGE);
   2590             goto err;
   2591         }
   2592     }
   2593 
   2594     return MSG_PROCESS_CONTINUE_READING;
   2595 err:
   2596     EVP_MD_CTX_free(md_ctx);
   2597     return MSG_PROCESS_ERROR;
   2598 }
   2599 
   2600 MSG_PROCESS_RETURN tls_process_certificate_request(SSL_CONNECTION *s,
   2601     PACKET *pkt)
   2602 {
   2603     /* Clear certificate validity flags */
   2604     if (s->s3.tmp.valid_flags != NULL)
   2605         memset(s->s3.tmp.valid_flags, 0, s->ssl_pkey_num * sizeof(uint32_t));
   2606     else
   2607         s->s3.tmp.valid_flags = OPENSSL_zalloc(s->ssl_pkey_num * sizeof(uint32_t));
   2608 
   2609     /* Give up for good if allocation didn't work */
   2610     if (s->s3.tmp.valid_flags == NULL)
   2611         return 0;
   2612 
   2613     if (SSL_CONNECTION_IS_TLS13(s)) {
   2614         PACKET reqctx, extensions;
   2615         RAW_EXTENSION *rawexts = NULL;
   2616 
   2617         if ((s->shutdown & SSL_SENT_SHUTDOWN) != 0) {
   2618             /*
   2619              * We already sent close_notify. This can only happen in TLSv1.3
   2620              * post-handshake messages. We can't reasonably respond to this, so
   2621              * we just ignore it
   2622              */
   2623             return MSG_PROCESS_FINISHED_READING;
   2624         }
   2625 
   2626         /* Free and zero certificate types: it is not present in TLS 1.3 */
   2627         OPENSSL_free(s->s3.tmp.ctype);
   2628         s->s3.tmp.ctype = NULL;
   2629         s->s3.tmp.ctype_len = 0;
   2630         OPENSSL_free(s->pha_context);
   2631         s->pha_context = NULL;
   2632         s->pha_context_len = 0;
   2633 
   2634         if (!PACKET_get_length_prefixed_1(pkt, &reqctx) || !PACKET_memdup(&reqctx, &s->pha_context, &s->pha_context_len)) {
   2635             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2636             return MSG_PROCESS_ERROR;
   2637         }
   2638 
   2639         if (!PACKET_get_length_prefixed_2(pkt, &extensions)) {
   2640             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
   2641             return MSG_PROCESS_ERROR;
   2642         }
   2643         if (!tls_collect_extensions(s, &extensions,
   2644                 SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
   2645                 &rawexts, NULL, 1)
   2646             || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
   2647                 rawexts, NULL, 0, 1)) {
   2648             /* SSLfatal() already called */
   2649             OPENSSL_free(rawexts);
   2650             return MSG_PROCESS_ERROR;
   2651         }
   2652         OPENSSL_free(rawexts);
   2653         if (!tls1_process_sigalgs(s)) {
   2654             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_LENGTH);
   2655             return MSG_PROCESS_ERROR;
   2656         }
   2657     } else {
   2658         PACKET ctypes;
   2659 
   2660         /* get the certificate types */
   2661         if (!PACKET_get_length_prefixed_1(pkt, &ctypes)) {
   2662             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2663             return MSG_PROCESS_ERROR;
   2664         }
   2665 
   2666         if (!PACKET_memdup(&ctypes, &s->s3.tmp.ctype, &s->s3.tmp.ctype_len)) {
   2667             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   2668             return MSG_PROCESS_ERROR;
   2669         }
   2670 
   2671         if (SSL_USE_SIGALGS(s)) {
   2672             PACKET sigalgs;
   2673 
   2674             if (!PACKET_get_length_prefixed_2(pkt, &sigalgs)) {
   2675                 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2676                 return MSG_PROCESS_ERROR;
   2677             }
   2678 
   2679             /*
   2680              * Despite this being for certificates, preserve compatibility
   2681              * with pre-TLS 1.3 and use the regular sigalgs field.
   2682              */
   2683             if (!tls1_save_sigalgs(s, &sigalgs, 0)) {
   2684                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
   2685                     SSL_R_SIGNATURE_ALGORITHMS_ERROR);
   2686                 return MSG_PROCESS_ERROR;
   2687             }
   2688             if (!tls1_process_sigalgs(s)) {
   2689                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SSL_LIB);
   2690                 return MSG_PROCESS_ERROR;
   2691             }
   2692         }
   2693 
   2694         /* get the CA RDNs */
   2695         if (!parse_ca_names(s, pkt)) {
   2696             /* SSLfatal() already called */
   2697             return MSG_PROCESS_ERROR;
   2698         }
   2699     }
   2700 
   2701     if (PACKET_remaining(pkt) != 0) {
   2702         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2703         return MSG_PROCESS_ERROR;
   2704     }
   2705 
   2706     /* we should setup a certificate to return.... */
   2707     s->s3.tmp.cert_req = 1;
   2708 
   2709     /*
   2710      * In TLSv1.3 we don't prepare the client certificate yet. We wait until
   2711      * after the CertificateVerify message has been received. This is because
   2712      * in TLSv1.3 the CertificateRequest arrives before the Certificate message
   2713      * but in TLSv1.2 it is the other way around. We want to make sure that
   2714      * SSL_get1_peer_certificate() returns something sensible in
   2715      * client_cert_cb.
   2716      */
   2717     if (SSL_CONNECTION_IS_TLS13(s)
   2718         && s->post_handshake_auth != SSL_PHA_REQUESTED)
   2719         return MSG_PROCESS_CONTINUE_READING;
   2720 
   2721     return MSG_PROCESS_CONTINUE_PROCESSING;
   2722 }
   2723 
   2724 MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL_CONNECTION *s,
   2725     PACKET *pkt)
   2726 {
   2727     unsigned int ticklen;
   2728     unsigned long ticket_lifetime_hint, age_add = 0;
   2729     unsigned int sess_len;
   2730     RAW_EXTENSION *exts = NULL;
   2731     PACKET nonce;
   2732     EVP_MD *sha256 = NULL;
   2733     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   2734 
   2735     PACKET_null_init(&nonce);
   2736 
   2737     if (!PACKET_get_net_4(pkt, &ticket_lifetime_hint)
   2738         || (SSL_CONNECTION_IS_TLS13(s)
   2739             && (!PACKET_get_net_4(pkt, &age_add)
   2740                 || !PACKET_get_length_prefixed_1(pkt, &nonce)))
   2741         || !PACKET_get_net_2(pkt, &ticklen)
   2742         || (SSL_CONNECTION_IS_TLS13(s) ? (ticklen == 0
   2743                                              || PACKET_remaining(pkt) < ticklen)
   2744                                        : PACKET_remaining(pkt) != ticklen)) {
   2745         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2746         goto err;
   2747     }
   2748 
   2749     /*
   2750      * Server is allowed to change its mind (in <=TLSv1.2) and send an empty
   2751      * ticket. We already checked this TLSv1.3 case above, so it should never
   2752      * be 0 here in that instance
   2753      */
   2754     if (ticklen == 0)
   2755         return MSG_PROCESS_CONTINUE_READING;
   2756 
   2757     /*
   2758      * Sessions must be immutable once they go into the session cache. Otherwise
   2759      * we can get multi-thread problems. Therefore we don't "update" sessions,
   2760      * we replace them with a duplicate. In TLSv1.3 we need to do this every
   2761      * time a NewSessionTicket arrives because those messages arrive
   2762      * post-handshake and the session may have already gone into the session
   2763      * cache.
   2764      */
   2765     if (SSL_CONNECTION_IS_TLS13(s) || s->session->session_id_length > 0) {
   2766         SSL_SESSION *new_sess;
   2767 
   2768         /*
   2769          * We reused an existing session, so we need to replace it with a new
   2770          * one
   2771          */
   2772         if ((new_sess = ssl_session_dup(s->session, 0)) == 0) {
   2773             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SSL_LIB);
   2774             goto err;
   2775         }
   2776 
   2777         if ((s->session_ctx->session_cache_mode & SSL_SESS_CACHE_CLIENT) != 0
   2778             && !SSL_CONNECTION_IS_TLS13(s)) {
   2779             /*
   2780              * In TLSv1.2 and below the arrival of a new tickets signals that
   2781              * any old ticket we were using is now out of date, so we remove the
   2782              * old session from the cache. We carry on if this fails
   2783              */
   2784             SSL_CTX_remove_session(s->session_ctx, s->session);
   2785         }
   2786 
   2787         SSL_SESSION_free(s->session);
   2788         s->session = new_sess;
   2789     }
   2790 
   2791     s->session->time = ossl_time_now();
   2792     ssl_session_calculate_timeout(s->session);
   2793 
   2794     OPENSSL_free(s->session->ext.tick);
   2795     s->session->ext.tick = NULL;
   2796     s->session->ext.ticklen = 0;
   2797 
   2798     s->session->ext.tick = OPENSSL_malloc(ticklen);
   2799     if (s->session->ext.tick == NULL) {
   2800         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   2801         goto err;
   2802     }
   2803     if (!PACKET_copy_bytes(pkt, s->session->ext.tick, ticklen)) {
   2804         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2805         goto err;
   2806     }
   2807 
   2808     s->session->ext.tick_lifetime_hint = ticket_lifetime_hint;
   2809     s->session->ext.tick_age_add = age_add;
   2810     s->session->ext.ticklen = ticklen;
   2811 
   2812     if (SSL_CONNECTION_IS_TLS13(s)) {
   2813         PACKET extpkt;
   2814 
   2815         if (!PACKET_as_length_prefixed_2(pkt, &extpkt)
   2816             || PACKET_remaining(pkt) != 0) {
   2817             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2818             goto err;
   2819         }
   2820 
   2821         if (!tls_collect_extensions(s, &extpkt,
   2822                 SSL_EXT_TLS1_3_NEW_SESSION_TICKET, &exts,
   2823                 NULL, 1)
   2824             || !tls_parse_all_extensions(s,
   2825                 SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
   2826                 exts, NULL, 0, 1)) {
   2827             /* SSLfatal() already called */
   2828             goto err;
   2829         }
   2830     }
   2831 
   2832     /*
   2833      * There are two ways to detect a resumed ticket session. One is to set
   2834      * an appropriate session ID and then the server must return a match in
   2835      * ServerHello. This allows the normal client session ID matching to work
   2836      * and we know much earlier that the ticket has been accepted. The
   2837      * other way is to set zero length session ID when the ticket is
   2838      * presented and rely on the handshake to determine session resumption.
   2839      * We choose the former approach because this fits in with assumptions
   2840      * elsewhere in OpenSSL. The session ID is set to the SHA256 hash of the
   2841      * ticket.
   2842      */
   2843     sha256 = EVP_MD_fetch(sctx->libctx, "SHA2-256", sctx->propq);
   2844     if (sha256 == NULL) {
   2845         /* Error is already recorded */
   2846         SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
   2847         goto err;
   2848     }
   2849     /*
   2850      * We use sess_len here because EVP_Digest expects an int
   2851      * but s->session->session_id_length is a size_t
   2852      */
   2853     if (!EVP_Digest(s->session->ext.tick, ticklen,
   2854             s->session->session_id, &sess_len,
   2855             sha256, NULL)) {
   2856         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   2857         goto err;
   2858     }
   2859     EVP_MD_free(sha256);
   2860     sha256 = NULL;
   2861     s->session->session_id_length = sess_len;
   2862     s->session->not_resumable = 0;
   2863 
   2864     /* This is a standalone message in TLSv1.3, so there is no more to read */
   2865     if (SSL_CONNECTION_IS_TLS13(s)) {
   2866         const EVP_MD *md = ssl_handshake_md(s);
   2867         int hashleni = EVP_MD_get_size(md);
   2868         size_t hashlen;
   2869         /* ASCII: "resumption", in hex for EBCDIC compatibility */
   2870         static const unsigned char nonce_label[] = { 0x72, 0x65, 0x73, 0x75, 0x6D,
   2871             0x70, 0x74, 0x69, 0x6F, 0x6E };
   2872 
   2873         /* Ensure cast to size_t is safe */
   2874         if (!ossl_assert(hashleni > 0)) {
   2875             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   2876             goto err;
   2877         }
   2878         hashlen = (size_t)hashleni;
   2879 
   2880         if (!tls13_hkdf_expand(s, md, s->resumption_master_secret,
   2881                 nonce_label,
   2882                 sizeof(nonce_label),
   2883                 PACKET_data(&nonce),
   2884                 PACKET_remaining(&nonce),
   2885                 s->session->master_key,
   2886                 hashlen, 1)) {
   2887             /* SSLfatal() already called */
   2888             goto err;
   2889         }
   2890         s->session->master_key_length = hashlen;
   2891 
   2892         OPENSSL_free(exts);
   2893         ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
   2894         return MSG_PROCESS_FINISHED_READING;
   2895     }
   2896 
   2897     return MSG_PROCESS_CONTINUE_READING;
   2898 err:
   2899     EVP_MD_free(sha256);
   2900     OPENSSL_free(exts);
   2901     return MSG_PROCESS_ERROR;
   2902 }
   2903 
   2904 /*
   2905  * In TLSv1.3 this is called from the extensions code, otherwise it is used to
   2906  * parse a separate message. Returns 1 on success or 0 on failure
   2907  */
   2908 int tls_process_cert_status_body(SSL_CONNECTION *s, PACKET *pkt)
   2909 {
   2910     size_t resplen;
   2911     unsigned int type;
   2912 
   2913     if (!PACKET_get_1(pkt, &type)
   2914         || type != TLSEXT_STATUSTYPE_ocsp) {
   2915         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_UNSUPPORTED_STATUS_TYPE);
   2916         return 0;
   2917     }
   2918     if (!PACKET_get_net_3_len(pkt, &resplen)
   2919         || PACKET_remaining(pkt) != resplen) {
   2920         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2921         return 0;
   2922     }
   2923     s->ext.ocsp.resp = OPENSSL_malloc(resplen);
   2924     if (s->ext.ocsp.resp == NULL) {
   2925         s->ext.ocsp.resp_len = 0;
   2926         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   2927         return 0;
   2928     }
   2929     s->ext.ocsp.resp_len = resplen;
   2930     if (!PACKET_copy_bytes(pkt, s->ext.ocsp.resp, resplen)) {
   2931         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   2932         return 0;
   2933     }
   2934 
   2935     return 1;
   2936 }
   2937 
   2938 MSG_PROCESS_RETURN tls_process_cert_status(SSL_CONNECTION *s, PACKET *pkt)
   2939 {
   2940     if (!tls_process_cert_status_body(s, pkt)) {
   2941         /* SSLfatal() already called */
   2942         return MSG_PROCESS_ERROR;
   2943     }
   2944 
   2945     return MSG_PROCESS_CONTINUE_READING;
   2946 }
   2947 
   2948 /*
   2949  * Perform miscellaneous checks and processing after we have received the
   2950  * server's initial flight. In TLS1.3 this is after the Server Finished message.
   2951  * In <=TLS1.2 this is after the ServerDone message. Returns 1 on success or 0
   2952  * on failure.
   2953  */
   2954 int tls_process_initial_server_flight(SSL_CONNECTION *s)
   2955 {
   2956     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   2957 
   2958     /*
   2959      * at this point we check that we have the required stuff from
   2960      * the server
   2961      */
   2962     if (!ssl3_check_cert_and_algorithm(s)) {
   2963         /* SSLfatal() already called */
   2964         return 0;
   2965     }
   2966 
   2967     /*
   2968      * Call the ocsp status callback if needed. The |ext.ocsp.resp| and
   2969      * |ext.ocsp.resp_len| values will be set if we actually received a status
   2970      * message, or NULL and -1 otherwise
   2971      */
   2972     if (s->ext.status_type != TLSEXT_STATUSTYPE_nothing
   2973         && sctx->ext.status_cb != NULL) {
   2974         int ret = sctx->ext.status_cb(SSL_CONNECTION_GET_USER_SSL(s),
   2975             sctx->ext.status_arg);
   2976 
   2977         if (ret == 0) {
   2978             SSLfatal(s, SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE,
   2979                 SSL_R_INVALID_STATUS_RESPONSE);
   2980             return 0;
   2981         }
   2982         if (ret < 0) {
   2983             SSLfatal(s, SSL_AD_INTERNAL_ERROR,
   2984                 SSL_R_OCSP_CALLBACK_FAILURE);
   2985             return 0;
   2986         }
   2987     }
   2988 #ifndef OPENSSL_NO_CT
   2989     if (s->ct_validation_callback != NULL) {
   2990         /* Note we validate the SCTs whether or not we abort on error */
   2991         if (!ssl_validate_ct(s) && (s->verify_mode & SSL_VERIFY_PEER)) {
   2992             /* SSLfatal() already called */
   2993             return 0;
   2994         }
   2995     }
   2996 #endif
   2997 
   2998     return 1;
   2999 }
   3000 
   3001 MSG_PROCESS_RETURN tls_process_server_done(SSL_CONNECTION *s, PACKET *pkt)
   3002 {
   3003     if (PACKET_remaining(pkt) > 0) {
   3004         /* should contain no data */
   3005         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   3006         return MSG_PROCESS_ERROR;
   3007     }
   3008 #ifndef OPENSSL_NO_SRP
   3009     if (s->s3.tmp.new_cipher->algorithm_mkey & SSL_kSRP) {
   3010         if (ssl_srp_calc_a_param_intern(s) <= 0) {
   3011             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_SRP_A_CALC);
   3012             return MSG_PROCESS_ERROR;
   3013         }
   3014     }
   3015 #endif
   3016 
   3017     if (!tls_process_initial_server_flight(s)) {
   3018         /* SSLfatal() already called */
   3019         return MSG_PROCESS_ERROR;
   3020     }
   3021 
   3022     return MSG_PROCESS_FINISHED_READING;
   3023 }
   3024 
   3025 static int tls_construct_cke_psk_preamble(SSL_CONNECTION *s, WPACKET *pkt)
   3026 {
   3027 #ifndef OPENSSL_NO_PSK
   3028     int ret = 0;
   3029     /*
   3030      * The callback needs PSK_MAX_IDENTITY_LEN + 1 bytes to return a
   3031      * \0-terminated identity. The last byte is for us for simulating
   3032      * strnlen.
   3033      */
   3034     char identity[PSK_MAX_IDENTITY_LEN + 1];
   3035     size_t identitylen = 0;
   3036     unsigned char psk[PSK_MAX_PSK_LEN];
   3037     unsigned char *tmppsk = NULL;
   3038     char *tmpidentity = NULL;
   3039     size_t psklen = 0;
   3040 
   3041     if (s->psk_client_callback == NULL) {
   3042         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PSK_NO_CLIENT_CB);
   3043         goto err;
   3044     }
   3045 
   3046     memset(identity, 0, sizeof(identity));
   3047 
   3048     psklen = s->psk_client_callback(SSL_CONNECTION_GET_USER_SSL(s),
   3049         s->session->psk_identity_hint,
   3050         identity, sizeof(identity) - 1,
   3051         psk, sizeof(psk));
   3052 
   3053     if (psklen > PSK_MAX_PSK_LEN) {
   3054         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, ERR_R_INTERNAL_ERROR);
   3055         psklen = PSK_MAX_PSK_LEN; /* Avoid overrunning the array on cleanse */
   3056         goto err;
   3057     } else if (psklen == 0) {
   3058         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_PSK_IDENTITY_NOT_FOUND);
   3059         goto err;
   3060     }
   3061 
   3062     identitylen = strlen(identity);
   3063     if (identitylen > PSK_MAX_IDENTITY_LEN) {
   3064         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3065         goto err;
   3066     }
   3067 
   3068     tmppsk = OPENSSL_memdup(psk, psklen);
   3069     tmpidentity = OPENSSL_strdup(identity);
   3070     if (tmppsk == NULL || tmpidentity == NULL) {
   3071         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   3072         goto err;
   3073     }
   3074 
   3075     OPENSSL_free(s->s3.tmp.psk);
   3076     s->s3.tmp.psk = tmppsk;
   3077     s->s3.tmp.psklen = psklen;
   3078     tmppsk = NULL;
   3079     OPENSSL_free(s->session->psk_identity);
   3080     s->session->psk_identity = tmpidentity;
   3081     tmpidentity = NULL;
   3082 
   3083     if (!WPACKET_sub_memcpy_u16(pkt, identity, identitylen)) {
   3084         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3085         goto err;
   3086     }
   3087 
   3088     ret = 1;
   3089 
   3090 err:
   3091     OPENSSL_cleanse(psk, psklen);
   3092     OPENSSL_cleanse(identity, sizeof(identity));
   3093     OPENSSL_clear_free(tmppsk, psklen);
   3094     OPENSSL_clear_free(tmpidentity, identitylen);
   3095 
   3096     return ret;
   3097 #else
   3098     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3099     return 0;
   3100 #endif
   3101 }
   3102 
   3103 static int tls_construct_cke_rsa(SSL_CONNECTION *s, WPACKET *pkt)
   3104 {
   3105     unsigned char *encdata = NULL;
   3106     EVP_PKEY *pkey = NULL;
   3107     EVP_PKEY_CTX *pctx = NULL;
   3108     size_t enclen;
   3109     unsigned char *pms = NULL;
   3110     size_t pmslen = 0;
   3111     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   3112 
   3113     if (!received_server_cert(s)) {
   3114         /*
   3115          * We should always have a server certificate with SSL_kRSA.
   3116          */
   3117         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3118         return 0;
   3119     }
   3120 
   3121     if ((pkey = tls_get_peer_pkey(s)) == NULL) {
   3122         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3123         return 0;
   3124     }
   3125 
   3126     if (!EVP_PKEY_is_a(pkey, "RSA")) {
   3127         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3128         return 0;
   3129     }
   3130 
   3131     pmslen = SSL_MAX_MASTER_KEY_LENGTH;
   3132     pms = OPENSSL_malloc(pmslen);
   3133     if (pms == NULL) {
   3134         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   3135         return 0;
   3136     }
   3137 
   3138     pms[0] = s->client_version >> 8;
   3139     pms[1] = s->client_version & 0xff;
   3140     if (RAND_bytes_ex(sctx->libctx, pms + 2, pmslen - 2, 0) <= 0) {
   3141         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_RAND_LIB);
   3142         goto err;
   3143     }
   3144 
   3145     /* Fix buf for TLS and beyond */
   3146     if (s->version > SSL3_VERSION && !WPACKET_start_sub_packet_u16(pkt)) {
   3147         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3148         goto err;
   3149     }
   3150 
   3151     pctx = EVP_PKEY_CTX_new_from_pkey(sctx->libctx, pkey, sctx->propq);
   3152     if (pctx == NULL || EVP_PKEY_encrypt_init(pctx) <= 0
   3153         || EVP_PKEY_encrypt(pctx, NULL, &enclen, pms, pmslen) <= 0) {
   3154         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   3155         goto err;
   3156     }
   3157     if (!WPACKET_allocate_bytes(pkt, enclen, &encdata)
   3158         || EVP_PKEY_encrypt(pctx, encdata, &enclen, pms, pmslen) <= 0) {
   3159         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_RSA_ENCRYPT);
   3160         goto err;
   3161     }
   3162     EVP_PKEY_CTX_free(pctx);
   3163     pctx = NULL;
   3164 
   3165     /* Fix buf for TLS and beyond */
   3166     if (s->version > SSL3_VERSION && !WPACKET_close(pkt)) {
   3167         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3168         goto err;
   3169     }
   3170 
   3171     /* Log the premaster secret, if logging is enabled. */
   3172     if (!ssl_log_rsa_client_key_exchange(s, encdata, enclen, pms, pmslen)) {
   3173         /* SSLfatal() already called */
   3174         goto err;
   3175     }
   3176 
   3177     s->s3.tmp.pms = pms;
   3178     s->s3.tmp.pmslen = pmslen;
   3179 
   3180     return 1;
   3181 err:
   3182     OPENSSL_clear_free(pms, pmslen);
   3183     EVP_PKEY_CTX_free(pctx);
   3184 
   3185     return 0;
   3186 }
   3187 
   3188 static int tls_construct_cke_dhe(SSL_CONNECTION *s, WPACKET *pkt)
   3189 {
   3190     EVP_PKEY *ckey = NULL, *skey = NULL;
   3191     unsigned char *keybytes = NULL;
   3192     int prime_len;
   3193     unsigned char *encoded_pub = NULL;
   3194     size_t encoded_pub_len, pad_len;
   3195     int ret = 0;
   3196 
   3197     skey = s->s3.peer_tmp;
   3198     if (skey == NULL) {
   3199         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3200         goto err;
   3201     }
   3202 
   3203     ckey = ssl_generate_pkey(s, skey);
   3204     if (ckey == NULL) {
   3205         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3206         goto err;
   3207     }
   3208 
   3209     if (ssl_derive(s, ckey, skey, 0) == 0) {
   3210         /* SSLfatal() already called */
   3211         goto err;
   3212     }
   3213 
   3214     /* send off the data */
   3215 
   3216     /* Generate encoding of server key */
   3217     encoded_pub_len = EVP_PKEY_get1_encoded_public_key(ckey, &encoded_pub);
   3218     if (encoded_pub_len == 0) {
   3219         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3220         EVP_PKEY_free(ckey);
   3221         return EXT_RETURN_FAIL;
   3222     }
   3223 
   3224     /*
   3225      * For interoperability with some versions of the Microsoft TLS
   3226      * stack, we need to zero pad the DHE pub key to the same length
   3227      * as the prime.
   3228      */
   3229     prime_len = EVP_PKEY_get_size(ckey);
   3230     pad_len = prime_len - encoded_pub_len;
   3231     if (pad_len > 0) {
   3232         if (!WPACKET_sub_allocate_bytes_u16(pkt, pad_len, &keybytes)) {
   3233             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3234             goto err;
   3235         }
   3236         memset(keybytes, 0, pad_len);
   3237     }
   3238 
   3239     if (!WPACKET_sub_memcpy_u16(pkt, encoded_pub, encoded_pub_len)) {
   3240         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3241         goto err;
   3242     }
   3243 
   3244     ret = 1;
   3245 err:
   3246     OPENSSL_free(encoded_pub);
   3247     EVP_PKEY_free(ckey);
   3248     return ret;
   3249 }
   3250 
   3251 static int tls_construct_cke_ecdhe(SSL_CONNECTION *s, WPACKET *pkt)
   3252 {
   3253     unsigned char *encodedPoint = NULL;
   3254     size_t encoded_pt_len = 0;
   3255     EVP_PKEY *ckey = NULL, *skey = NULL;
   3256     int ret = 0;
   3257 
   3258     skey = s->s3.peer_tmp;
   3259     if (skey == NULL) {
   3260         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3261         return 0;
   3262     }
   3263 
   3264     ckey = ssl_generate_pkey(s, skey);
   3265     if (ckey == NULL) {
   3266         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SSL_LIB);
   3267         goto err;
   3268     }
   3269 
   3270     if (ssl_derive(s, ckey, skey, 0) == 0) {
   3271         /* SSLfatal() already called */
   3272         goto err;
   3273     }
   3274 
   3275     /* Generate encoding of client key */
   3276     encoded_pt_len = EVP_PKEY_get1_encoded_public_key(ckey, &encodedPoint);
   3277 
   3278     if (encoded_pt_len == 0) {
   3279         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EC_LIB);
   3280         goto err;
   3281     }
   3282 
   3283     if (!WPACKET_sub_memcpy_u8(pkt, encodedPoint, encoded_pt_len)) {
   3284         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3285         goto err;
   3286     }
   3287 
   3288     ret = 1;
   3289 err:
   3290     OPENSSL_free(encodedPoint);
   3291     EVP_PKEY_free(ckey);
   3292     return ret;
   3293 }
   3294 
   3295 static int tls_construct_cke_gost(SSL_CONNECTION *s, WPACKET *pkt)
   3296 {
   3297 #ifndef OPENSSL_NO_GOST
   3298     /* GOST key exchange message creation */
   3299     EVP_PKEY_CTX *pkey_ctx = NULL;
   3300     EVP_PKEY *pkey = NULL;
   3301     size_t msglen;
   3302     unsigned int md_len;
   3303     unsigned char shared_ukm[32], tmp[256];
   3304     EVP_MD_CTX *ukm_hash = NULL;
   3305     int dgst_nid = NID_id_GostR3411_94;
   3306     unsigned char *pms = NULL;
   3307     size_t pmslen = 0;
   3308     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   3309 
   3310     if ((s->s3.tmp.new_cipher->algorithm_auth & SSL_aGOST12) != 0)
   3311         dgst_nid = NID_id_GostR3411_2012_256;
   3312 
   3313     /*
   3314      * Get server certificate PKEY and create ctx from it
   3315      */
   3316     if ((pkey = tls_get_peer_pkey(s)) == NULL) {
   3317         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
   3318             SSL_R_NO_GOST_CERTIFICATE_SENT_BY_PEER);
   3319         return 0;
   3320     }
   3321 
   3322     pkey_ctx = EVP_PKEY_CTX_new_from_pkey(sctx->libctx,
   3323         pkey,
   3324         sctx->propq);
   3325     if (pkey_ctx == NULL) {
   3326         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   3327         return 0;
   3328     }
   3329     /*
   3330      * If we have send a certificate, and certificate key
   3331      * parameters match those of server certificate, use
   3332      * certificate key for key exchange
   3333      */
   3334 
   3335     /* Otherwise, generate ephemeral key pair */
   3336     pmslen = 32;
   3337     pms = OPENSSL_malloc(pmslen);
   3338     if (pms == NULL) {
   3339         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   3340         goto err;
   3341     }
   3342 
   3343     if (EVP_PKEY_encrypt_init(pkey_ctx) <= 0
   3344         /* Generate session key
   3345          */
   3346         || RAND_bytes_ex(sctx->libctx, pms, pmslen, 0) <= 0) {
   3347         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3348         goto err;
   3349     };
   3350     /*
   3351      * Compute shared IV and store it in algorithm-specific context
   3352      * data
   3353      */
   3354     ukm_hash = EVP_MD_CTX_new();
   3355     if (ukm_hash == NULL
   3356         || EVP_DigestInit(ukm_hash, EVP_get_digestbynid(dgst_nid)) <= 0
   3357         || EVP_DigestUpdate(ukm_hash, s->s3.client_random,
   3358                SSL3_RANDOM_SIZE)
   3359             <= 0
   3360         || EVP_DigestUpdate(ukm_hash, s->s3.server_random,
   3361                SSL3_RANDOM_SIZE)
   3362             <= 0
   3363         || EVP_DigestFinal_ex(ukm_hash, shared_ukm, &md_len) <= 0) {
   3364         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3365         goto err;
   3366     }
   3367     EVP_MD_CTX_free(ukm_hash);
   3368     ukm_hash = NULL;
   3369     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
   3370             EVP_PKEY_CTRL_SET_IV, 8, shared_ukm)
   3371         <= 0) {
   3372         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
   3373         goto err;
   3374     }
   3375     /* Make GOST keytransport blob message */
   3376     /*
   3377      * Encapsulate it into sequence
   3378      */
   3379     msglen = 255;
   3380     if (EVP_PKEY_encrypt(pkey_ctx, tmp, &msglen, pms, pmslen) <= 0) {
   3381         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
   3382         goto err;
   3383     }
   3384 
   3385     if (!WPACKET_put_bytes_u8(pkt, V_ASN1_SEQUENCE | V_ASN1_CONSTRUCTED)
   3386         || (msglen >= 0x80 && !WPACKET_put_bytes_u8(pkt, 0x81))
   3387         || !WPACKET_sub_memcpy_u8(pkt, tmp, msglen)) {
   3388         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3389         goto err;
   3390     }
   3391 
   3392     EVP_PKEY_CTX_free(pkey_ctx);
   3393     s->s3.tmp.pms = pms;
   3394     s->s3.tmp.pmslen = pmslen;
   3395 
   3396     return 1;
   3397 err:
   3398     EVP_PKEY_CTX_free(pkey_ctx);
   3399     OPENSSL_clear_free(pms, pmslen);
   3400     EVP_MD_CTX_free(ukm_hash);
   3401     return 0;
   3402 #else
   3403     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3404     return 0;
   3405 #endif
   3406 }
   3407 
   3408 #ifndef OPENSSL_NO_GOST
   3409 int ossl_gost18_cke_cipher_nid(const SSL_CONNECTION *s)
   3410 {
   3411     if ((s->s3.tmp.new_cipher->algorithm_enc & SSL_MAGMA) != 0)
   3412         return NID_magma_ctr;
   3413     else if ((s->s3.tmp.new_cipher->algorithm_enc & SSL_KUZNYECHIK) != 0)
   3414         return NID_kuznyechik_ctr;
   3415 
   3416     return NID_undef;
   3417 }
   3418 
   3419 int ossl_gost_ukm(const SSL_CONNECTION *s, unsigned char *dgst_buf)
   3420 {
   3421     EVP_MD_CTX *hash = NULL;
   3422     unsigned int md_len;
   3423     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   3424     const EVP_MD *md = ssl_evp_md_fetch(sctx->libctx, NID_id_GostR3411_2012_256,
   3425         sctx->propq);
   3426 
   3427     if (md == NULL)
   3428         return 0;
   3429 
   3430     if ((hash = EVP_MD_CTX_new()) == NULL
   3431         || EVP_DigestInit(hash, md) <= 0
   3432         || EVP_DigestUpdate(hash, s->s3.client_random, SSL3_RANDOM_SIZE) <= 0
   3433         || EVP_DigestUpdate(hash, s->s3.server_random, SSL3_RANDOM_SIZE) <= 0
   3434         || EVP_DigestFinal_ex(hash, dgst_buf, &md_len) <= 0) {
   3435         EVP_MD_CTX_free(hash);
   3436         ssl_evp_md_free(md);
   3437         return 0;
   3438     }
   3439 
   3440     EVP_MD_CTX_free(hash);
   3441     ssl_evp_md_free(md);
   3442     return 1;
   3443 }
   3444 #endif
   3445 
   3446 static int tls_construct_cke_gost18(SSL_CONNECTION *s, WPACKET *pkt)
   3447 {
   3448 #ifndef OPENSSL_NO_GOST
   3449     /* GOST 2018 key exchange message creation */
   3450     unsigned char rnd_dgst[32];
   3451     unsigned char *encdata = NULL;
   3452     EVP_PKEY_CTX *pkey_ctx = NULL;
   3453     EVP_PKEY *pkey;
   3454     unsigned char *pms = NULL;
   3455     size_t pmslen = 0;
   3456     size_t msglen;
   3457     int cipher_nid = ossl_gost18_cke_cipher_nid(s);
   3458     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   3459 
   3460     if (cipher_nid == NID_undef) {
   3461         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3462         return 0;
   3463     }
   3464 
   3465     if (ossl_gost_ukm(s, rnd_dgst) <= 0) {
   3466         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3467         goto err;
   3468     }
   3469 
   3470     /* Pre-master secret - random bytes */
   3471     pmslen = 32;
   3472     pms = OPENSSL_malloc(pmslen);
   3473     if (pms == NULL) {
   3474         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   3475         goto err;
   3476     }
   3477 
   3478     if (RAND_bytes_ex(sctx->libctx, pms, pmslen, 0) <= 0) {
   3479         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3480         goto err;
   3481     }
   3482 
   3483     /* Get server certificate PKEY and create ctx from it */
   3484     if ((pkey = tls_get_peer_pkey(s)) == NULL) {
   3485         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
   3486             SSL_R_NO_GOST_CERTIFICATE_SENT_BY_PEER);
   3487         goto err;
   3488     }
   3489 
   3490     pkey_ctx = EVP_PKEY_CTX_new_from_pkey(sctx->libctx,
   3491         pkey,
   3492         sctx->propq);
   3493     if (pkey_ctx == NULL) {
   3494         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   3495         goto err;
   3496     }
   3497 
   3498     if (EVP_PKEY_encrypt_init(pkey_ctx) <= 0) {
   3499         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3500         goto err;
   3501     };
   3502 
   3503     /* Reuse EVP_PKEY_CTRL_SET_IV, make choice in engine code */
   3504     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
   3505             EVP_PKEY_CTRL_SET_IV, 32, rnd_dgst)
   3506         <= 0) {
   3507         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
   3508         goto err;
   3509     }
   3510 
   3511     if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
   3512             EVP_PKEY_CTRL_CIPHER, cipher_nid, NULL)
   3513         <= 0) {
   3514         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
   3515         goto err;
   3516     }
   3517 
   3518     if (EVP_PKEY_encrypt(pkey_ctx, NULL, &msglen, pms, pmslen) <= 0) {
   3519         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   3520         goto err;
   3521     }
   3522 
   3523     if (!WPACKET_allocate_bytes(pkt, msglen, &encdata)
   3524         || EVP_PKEY_encrypt(pkey_ctx, encdata, &msglen, pms, pmslen) <= 0) {
   3525         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
   3526         goto err;
   3527     }
   3528 
   3529     EVP_PKEY_CTX_free(pkey_ctx);
   3530     pkey_ctx = NULL;
   3531     s->s3.tmp.pms = pms;
   3532     s->s3.tmp.pmslen = pmslen;
   3533 
   3534     return 1;
   3535 err:
   3536     EVP_PKEY_CTX_free(pkey_ctx);
   3537     OPENSSL_clear_free(pms, pmslen);
   3538     return 0;
   3539 #else
   3540     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3541     return 0;
   3542 #endif
   3543 }
   3544 
   3545 static int tls_construct_cke_srp(SSL_CONNECTION *s, WPACKET *pkt)
   3546 {
   3547 #ifndef OPENSSL_NO_SRP
   3548     unsigned char *abytes = NULL;
   3549 
   3550     if (s->srp_ctx.A == NULL
   3551         || !WPACKET_sub_allocate_bytes_u16(pkt, BN_num_bytes(s->srp_ctx.A),
   3552             &abytes)) {
   3553         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3554         return 0;
   3555     }
   3556     BN_bn2bin(s->srp_ctx.A, abytes);
   3557 
   3558     OPENSSL_free(s->session->srp_username);
   3559     s->session->srp_username = OPENSSL_strdup(s->srp_ctx.login);
   3560     if (s->session->srp_username == NULL) {
   3561         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
   3562         return 0;
   3563     }
   3564 
   3565     return 1;
   3566 #else
   3567     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3568     return 0;
   3569 #endif
   3570 }
   3571 
   3572 CON_FUNC_RETURN tls_construct_client_key_exchange(SSL_CONNECTION *s,
   3573     WPACKET *pkt)
   3574 {
   3575     unsigned long alg_k;
   3576 
   3577     alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
   3578 
   3579     /*
   3580      * All of the construct functions below call SSLfatal() if necessary so
   3581      * no need to do so here.
   3582      */
   3583     if ((alg_k & SSL_PSK)
   3584         && !tls_construct_cke_psk_preamble(s, pkt))
   3585         goto err;
   3586 
   3587     if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) {
   3588         if (!tls_construct_cke_rsa(s, pkt))
   3589             goto err;
   3590     } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
   3591         if (!tls_construct_cke_dhe(s, pkt))
   3592             goto err;
   3593     } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
   3594         if (!tls_construct_cke_ecdhe(s, pkt))
   3595             goto err;
   3596     } else if (alg_k & SSL_kGOST) {
   3597         if (!tls_construct_cke_gost(s, pkt))
   3598             goto err;
   3599     } else if (alg_k & SSL_kGOST18) {
   3600         if (!tls_construct_cke_gost18(s, pkt))
   3601             goto err;
   3602     } else if (alg_k & SSL_kSRP) {
   3603         if (!tls_construct_cke_srp(s, pkt))
   3604             goto err;
   3605     } else if (!(alg_k & SSL_kPSK)) {
   3606         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3607         goto err;
   3608     }
   3609 
   3610     return CON_FUNC_SUCCESS;
   3611 err:
   3612     OPENSSL_clear_free(s->s3.tmp.pms, s->s3.tmp.pmslen);
   3613     s->s3.tmp.pms = NULL;
   3614     s->s3.tmp.pmslen = 0;
   3615 #ifndef OPENSSL_NO_PSK
   3616     OPENSSL_clear_free(s->s3.tmp.psk, s->s3.tmp.psklen);
   3617     s->s3.tmp.psk = NULL;
   3618     s->s3.tmp.psklen = 0;
   3619 #endif
   3620     return CON_FUNC_ERROR;
   3621 }
   3622 
   3623 int tls_client_key_exchange_post_work(SSL_CONNECTION *s)
   3624 {
   3625     unsigned char *pms = NULL;
   3626     size_t pmslen = 0;
   3627 
   3628     pms = s->s3.tmp.pms;
   3629     pmslen = s->s3.tmp.pmslen;
   3630 
   3631 #ifndef OPENSSL_NO_SRP
   3632     /* Check for SRP */
   3633     if (s->s3.tmp.new_cipher->algorithm_mkey & SSL_kSRP) {
   3634         if (!srp_generate_client_master_secret(s)) {
   3635             /* SSLfatal() already called */
   3636             goto err;
   3637         }
   3638         return 1;
   3639     }
   3640 #endif
   3641 
   3642     if (pms == NULL && !(s->s3.tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
   3643         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_PASSED_INVALID_ARGUMENT);
   3644         goto err;
   3645     }
   3646     if (!ssl_generate_master_secret(s, pms, pmslen, 1)) {
   3647         /* SSLfatal() already called */
   3648         /* ssl_generate_master_secret frees the pms even on error */
   3649         pms = NULL;
   3650         pmslen = 0;
   3651         goto err;
   3652     }
   3653     pms = NULL;
   3654     pmslen = 0;
   3655 
   3656 #ifndef OPENSSL_NO_SCTP
   3657     if (SSL_CONNECTION_IS_DTLS(s)) {
   3658         unsigned char sctpauthkey[64];
   3659         char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
   3660         size_t labellen;
   3661         SSL *ssl = SSL_CONNECTION_GET_SSL(s);
   3662 
   3663         /*
   3664          * Add new shared key for SCTP-Auth, will be ignored if no SCTP
   3665          * used.
   3666          */
   3667         memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
   3668             sizeof(DTLS1_SCTP_AUTH_LABEL));
   3669 
   3670         /* Don't include the terminating zero. */
   3671         labellen = sizeof(labelbuffer) - 1;
   3672         if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
   3673             labellen += 1;
   3674 
   3675         if (SSL_export_keying_material(ssl, sctpauthkey,
   3676                 sizeof(sctpauthkey), labelbuffer,
   3677                 labellen, NULL, 0, 0)
   3678             <= 0) {
   3679             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3680             goto err;
   3681         }
   3682 
   3683         BIO_ctrl(SSL_get_wbio(ssl), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
   3684             sizeof(sctpauthkey), sctpauthkey);
   3685     }
   3686 #endif
   3687 
   3688     return 1;
   3689 err:
   3690     OPENSSL_clear_free(pms, pmslen);
   3691     s->s3.tmp.pms = NULL;
   3692     s->s3.tmp.pmslen = 0;
   3693     return 0;
   3694 }
   3695 
   3696 /*
   3697  * Check a certificate can be used for client authentication. Currently check
   3698  * cert exists, if we have a suitable digest for TLS 1.2 if static DH client
   3699  * certificates can be used and optionally checks suitability for Suite B.
   3700  */
   3701 static int ssl3_check_client_certificate(SSL_CONNECTION *s)
   3702 {
   3703     /* If no suitable signature algorithm can't use certificate */
   3704     if (!tls_choose_sigalg(s, 0) || s->s3.tmp.sigalg == NULL)
   3705         return 0;
   3706     /*
   3707      * If strict mode check suitability of chain before using it. This also
   3708      * adjusts suite B digest if necessary.
   3709      */
   3710     if (s->cert->cert_flags & SSL_CERT_FLAGS_CHECK_TLS_STRICT && !tls1_check_chain(s, NULL, NULL, NULL, -2))
   3711         return 0;
   3712     return 1;
   3713 }
   3714 
   3715 WORK_STATE tls_prepare_client_certificate(SSL_CONNECTION *s, WORK_STATE wst)
   3716 {
   3717     X509 *x509 = NULL;
   3718     EVP_PKEY *pkey = NULL;
   3719     int i;
   3720     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
   3721 
   3722     if (wst == WORK_MORE_A) {
   3723         /* Let cert callback update client certificates if required */
   3724         if (s->cert->cert_cb) {
   3725             i = s->cert->cert_cb(ssl, s->cert->cert_cb_arg);
   3726             if (i < 0) {
   3727                 s->rwstate = SSL_X509_LOOKUP;
   3728                 return WORK_MORE_A;
   3729             }
   3730             if (i == 0) {
   3731                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_CALLBACK_FAILED);
   3732                 return WORK_ERROR;
   3733             }
   3734             s->rwstate = SSL_NOTHING;
   3735         }
   3736         if (ssl3_check_client_certificate(s)) {
   3737             if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
   3738                 return WORK_FINISHED_STOP;
   3739             }
   3740             return WORK_FINISHED_CONTINUE;
   3741         }
   3742 
   3743         /* Fall through to WORK_MORE_B */
   3744         wst = WORK_MORE_B;
   3745     }
   3746 
   3747     /* We need to get a client cert */
   3748     if (wst == WORK_MORE_B) {
   3749         /*
   3750          * If we get an error, we need to ssl->rwstate=SSL_X509_LOOKUP;
   3751          * return(-1); We then get retied later
   3752          */
   3753         i = ssl_do_client_cert_cb(s, &x509, &pkey);
   3754         if (i < 0) {
   3755             s->rwstate = SSL_X509_LOOKUP;
   3756             return WORK_MORE_B;
   3757         }
   3758         s->rwstate = SSL_NOTHING;
   3759         if ((i == 1) && (pkey != NULL) && (x509 != NULL)) {
   3760             if (!SSL_use_certificate(ssl, x509)
   3761                 || !SSL_use_PrivateKey(ssl, pkey))
   3762                 i = 0;
   3763         } else if (i == 1) {
   3764             i = 0;
   3765             ERR_raise(ERR_LIB_SSL, SSL_R_BAD_DATA_RETURNED_BY_CALLBACK);
   3766         }
   3767 
   3768         X509_free(x509);
   3769         EVP_PKEY_free(pkey);
   3770         if (i && !ssl3_check_client_certificate(s))
   3771             i = 0;
   3772         if (i == 0) {
   3773             if (s->version == SSL3_VERSION) {
   3774                 s->s3.tmp.cert_req = 0;
   3775                 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_CERTIFICATE);
   3776                 return WORK_FINISHED_CONTINUE;
   3777             } else {
   3778                 s->s3.tmp.cert_req = 2;
   3779                 s->ext.compress_certificate_from_peer[0] = TLSEXT_comp_cert_none;
   3780                 if (!ssl3_digest_cached_records(s, 0)) {
   3781                     /* SSLfatal() already called */
   3782                     return WORK_ERROR;
   3783                 }
   3784             }
   3785         }
   3786 
   3787         if (!SSL_CONNECTION_IS_TLS13(s)
   3788             || (s->options & SSL_OP_NO_TX_CERTIFICATE_COMPRESSION) != 0)
   3789             s->ext.compress_certificate_from_peer[0] = TLSEXT_comp_cert_none;
   3790 
   3791         if (s->post_handshake_auth == SSL_PHA_REQUESTED)
   3792             return WORK_FINISHED_STOP;
   3793         return WORK_FINISHED_CONTINUE;
   3794     }
   3795 
   3796     /* Shouldn't ever get here */
   3797     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3798     return WORK_ERROR;
   3799 }
   3800 
   3801 CON_FUNC_RETURN tls_construct_client_certificate(SSL_CONNECTION *s,
   3802     WPACKET *pkt)
   3803 {
   3804     CERT_PKEY *cpk = NULL;
   3805     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
   3806 
   3807     if (SSL_CONNECTION_IS_TLS13(s)) {
   3808         if (s->pha_context == NULL) {
   3809             /* no context available, add 0-length context */
   3810             if (!WPACKET_put_bytes_u8(pkt, 0)) {
   3811                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3812                 return CON_FUNC_ERROR;
   3813             }
   3814         } else if (!WPACKET_sub_memcpy_u8(pkt, s->pha_context, s->pha_context_len)) {
   3815             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3816             return CON_FUNC_ERROR;
   3817         }
   3818     }
   3819     if (s->s3.tmp.cert_req != 2)
   3820         cpk = s->cert->key;
   3821     switch (s->ext.client_cert_type) {
   3822     case TLSEXT_cert_type_rpk:
   3823         if (!tls_output_rpk(s, pkt, cpk)) {
   3824             /* SSLfatal() already called */
   3825             return CON_FUNC_ERROR;
   3826         }
   3827         break;
   3828     case TLSEXT_cert_type_x509:
   3829         if (!ssl3_output_cert_chain(s, pkt, cpk, 0)) {
   3830             /* SSLfatal() already called */
   3831             return CON_FUNC_ERROR;
   3832         }
   3833         break;
   3834     default:
   3835         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3836         return CON_FUNC_ERROR;
   3837     }
   3838 
   3839     /*
   3840      * If we attempted to write early data or we're in middlebox compat mode
   3841      * then we deferred changing the handshake write keys to the last possible
   3842      * moment. We need to do it now.
   3843      */
   3844     if (SSL_CONNECTION_IS_TLS13(s)
   3845         && !SSL_IS_QUIC_HANDSHAKE(s)
   3846         && SSL_IS_FIRST_HANDSHAKE(s)
   3847         && (s->early_data_state != SSL_EARLY_DATA_NONE
   3848             || (s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0)
   3849         && (!ssl->method->ssl3_enc->change_cipher_state(s,
   3850             SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_WRITE))) {
   3851         /*
   3852          * This is a fatal error, which leaves enc_write_ctx in an inconsistent
   3853          * state and thus ssl3_send_alert may crash.
   3854          */
   3855         SSLfatal(s, SSL_AD_NO_ALERT, SSL_R_CANNOT_CHANGE_CIPHER);
   3856         return CON_FUNC_ERROR;
   3857     }
   3858 
   3859     return CON_FUNC_SUCCESS;
   3860 }
   3861 
   3862 #ifndef OPENSSL_NO_COMP_ALG
   3863 CON_FUNC_RETURN tls_construct_client_compressed_certificate(SSL_CONNECTION *sc,
   3864     WPACKET *pkt)
   3865 {
   3866     SSL *ssl = SSL_CONNECTION_GET_SSL(sc);
   3867     WPACKET tmppkt;
   3868     BUF_MEM *buf = NULL;
   3869     size_t length;
   3870     size_t max_length;
   3871     COMP_METHOD *method;
   3872     COMP_CTX *comp = NULL;
   3873     int comp_len;
   3874     int ret = 0;
   3875     int alg = sc->ext.compress_certificate_from_peer[0];
   3876 
   3877     /* Note that sc->s3.tmp.cert_req == 2 is checked in write transition */
   3878 
   3879     if ((buf = BUF_MEM_new()) == NULL || !WPACKET_init(&tmppkt, buf))
   3880         goto err;
   3881 
   3882     /* Use the |tmppkt| for the to-be-compressed data */
   3883     if (sc->pha_context == NULL) {
   3884         /* no context available, add 0-length context */
   3885         if (!WPACKET_put_bytes_u8(&tmppkt, 0))
   3886             goto err;
   3887     } else if (!WPACKET_sub_memcpy_u8(&tmppkt, sc->pha_context, sc->pha_context_len))
   3888         goto err;
   3889 
   3890     if (!ssl3_output_cert_chain(sc, &tmppkt, sc->cert->key, 0)) {
   3891         /* SSLfatal() already called */
   3892         goto out;
   3893     }
   3894 
   3895     /* continue with the real |pkt| */
   3896     if (!WPACKET_put_bytes_u16(pkt, alg)
   3897         || !WPACKET_get_total_written(&tmppkt, &length)
   3898         || !WPACKET_put_bytes_u24(pkt, length))
   3899         goto err;
   3900 
   3901     switch (alg) {
   3902     case TLSEXT_comp_cert_zlib:
   3903         method = COMP_zlib_oneshot();
   3904         break;
   3905     case TLSEXT_comp_cert_brotli:
   3906         method = COMP_brotli_oneshot();
   3907         break;
   3908     case TLSEXT_comp_cert_zstd:
   3909         method = COMP_zstd_oneshot();
   3910         break;
   3911     default:
   3912         goto err;
   3913     }
   3914     max_length = ossl_calculate_comp_expansion(alg, length);
   3915 
   3916     if ((comp = COMP_CTX_new(method)) == NULL
   3917         || !WPACKET_start_sub_packet_u24(pkt)
   3918         || !WPACKET_reserve_bytes(pkt, max_length, NULL))
   3919         goto err;
   3920 
   3921     comp_len = COMP_compress_block(comp, WPACKET_get_curr(pkt), max_length,
   3922         (unsigned char *)buf->data, length);
   3923     if (comp_len <= 0)
   3924         goto err;
   3925 
   3926     if (!WPACKET_allocate_bytes(pkt, comp_len, NULL)
   3927         || !WPACKET_close(pkt))
   3928         goto err;
   3929 
   3930     /*
   3931      * If we attempted to write early data or we're in middlebox compat mode
   3932      * then we deferred changing the handshake write keys to the last possible
   3933      * moment. We need to do it now.
   3934      */
   3935     if (SSL_IS_FIRST_HANDSHAKE(sc)
   3936         && !SSL_IS_QUIC_HANDSHAKE(sc)
   3937         && (sc->early_data_state != SSL_EARLY_DATA_NONE
   3938             || (sc->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0)
   3939         && (!ssl->method->ssl3_enc->change_cipher_state(sc,
   3940             SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_WRITE))) {
   3941         /*
   3942          * This is a fatal error, which leaves sc->enc_write_ctx in an
   3943          * inconsistent state and thus ssl3_send_alert may crash.
   3944          */
   3945         SSLfatal(sc, SSL_AD_NO_ALERT, SSL_R_CANNOT_CHANGE_CIPHER);
   3946         goto out;
   3947     }
   3948     ret = 1;
   3949     goto out;
   3950 
   3951 err:
   3952     SSLfatal(sc, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3953 out:
   3954     if (buf != NULL) {
   3955         /* If |buf| is NULL, then |tmppkt| could not have been initialized */
   3956         WPACKET_cleanup(&tmppkt);
   3957     }
   3958     BUF_MEM_free(buf);
   3959     COMP_CTX_free(comp);
   3960     return ret;
   3961 }
   3962 #endif
   3963 
   3964 int ssl3_check_cert_and_algorithm(SSL_CONNECTION *s)
   3965 {
   3966     const SSL_CERT_LOOKUP *clu;
   3967     size_t idx;
   3968     long alg_k, alg_a;
   3969     EVP_PKEY *pkey;
   3970 
   3971     alg_k = s->s3.tmp.new_cipher->algorithm_mkey;
   3972     alg_a = s->s3.tmp.new_cipher->algorithm_auth;
   3973 
   3974     /* we don't have a certificate */
   3975     if (!(alg_a & SSL_aCERT))
   3976         return 1;
   3977 
   3978     /* This is the passed certificate */
   3979     pkey = tls_get_peer_pkey(s);
   3980     clu = ssl_cert_lookup_by_pkey(pkey, &idx, SSL_CONNECTION_GET_CTX(s));
   3981 
   3982     /* Check certificate is recognised and suitable for cipher */
   3983     if (clu == NULL || (alg_a & clu->amask) == 0) {
   3984         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_MISSING_SIGNING_CERT);
   3985         return 0;
   3986     }
   3987 
   3988     if (alg_k & (SSL_kRSA | SSL_kRSAPSK) && idx != SSL_PKEY_RSA) {
   3989         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
   3990             SSL_R_MISSING_RSA_ENCRYPTING_CERT);
   3991         return 0;
   3992     }
   3993 
   3994     if ((alg_k & SSL_kDHE) && (s->s3.peer_tmp == NULL)) {
   3995         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   3996         return 0;
   3997     }
   3998 
   3999     /* Early out to skip the checks below */
   4000     if (s->session->peer_rpk != NULL)
   4001         return 1;
   4002 
   4003     if (clu->amask & SSL_aECDSA) {
   4004         if (ssl_check_srvr_ecc_cert_and_alg(s->session->peer, s))
   4005             return 1;
   4006         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_BAD_ECC_CERT);
   4007         return 0;
   4008     }
   4009 
   4010     return 1;
   4011 }
   4012 
   4013 #ifndef OPENSSL_NO_NEXTPROTONEG
   4014 CON_FUNC_RETURN tls_construct_next_proto(SSL_CONNECTION *s, WPACKET *pkt)
   4015 {
   4016     size_t len, padding_len;
   4017     unsigned char *padding = NULL;
   4018 
   4019     len = s->ext.npn_len;
   4020     padding_len = 32 - ((len + 2) % 32);
   4021 
   4022     if (!WPACKET_sub_memcpy_u8(pkt, s->ext.npn, len)
   4023         || !WPACKET_sub_allocate_bytes_u8(pkt, padding_len, &padding)) {
   4024         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   4025         return CON_FUNC_ERROR;
   4026     }
   4027 
   4028     memset(padding, 0, padding_len);
   4029 
   4030     return CON_FUNC_SUCCESS;
   4031 }
   4032 #endif
   4033 
   4034 MSG_PROCESS_RETURN tls_process_hello_req(SSL_CONNECTION *s, PACKET *pkt)
   4035 {
   4036     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
   4037 
   4038     if (PACKET_remaining(pkt) > 0) {
   4039         /* should contain no data */
   4040         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   4041         return MSG_PROCESS_ERROR;
   4042     }
   4043 
   4044     if ((s->options & SSL_OP_NO_RENEGOTIATION)) {
   4045         ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
   4046         return MSG_PROCESS_FINISHED_READING;
   4047     }
   4048 
   4049     /*
   4050      * This is a historical discrepancy (not in the RFC) maintained for
   4051      * compatibility reasons. If a TLS client receives a HelloRequest it will
   4052      * attempt an abbreviated handshake. However if a DTLS client receives a
   4053      * HelloRequest it will do a full handshake. Either behaviour is reasonable
   4054      * but doing one for TLS and another for DTLS is odd.
   4055      */
   4056     if (SSL_CONNECTION_IS_DTLS(s))
   4057         SSL_renegotiate(ssl);
   4058     else
   4059         SSL_renegotiate_abbreviated(ssl);
   4060 
   4061     return MSG_PROCESS_FINISHED_READING;
   4062 }
   4063 
   4064 static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL_CONNECTION *s,
   4065     PACKET *pkt)
   4066 {
   4067     PACKET extensions;
   4068     RAW_EXTENSION *rawexts = NULL;
   4069 
   4070     if (!PACKET_as_length_prefixed_2(pkt, &extensions)
   4071         || PACKET_remaining(pkt) != 0) {
   4072         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
   4073         goto err;
   4074     }
   4075 
   4076     if (!tls_collect_extensions(s, &extensions,
   4077             SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS, &rawexts,
   4078             NULL, 1)
   4079         || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
   4080             rawexts, NULL, 0, 1)) {
   4081         /* SSLfatal() already called */
   4082         goto err;
   4083     }
   4084 
   4085     OPENSSL_free(rawexts);
   4086     return MSG_PROCESS_CONTINUE_READING;
   4087 
   4088 err:
   4089     OPENSSL_free(rawexts);
   4090     return MSG_PROCESS_ERROR;
   4091 }
   4092 
   4093 int ssl_do_client_cert_cb(SSL_CONNECTION *s, X509 **px509, EVP_PKEY **ppkey)
   4094 {
   4095     int i = 0;
   4096     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
   4097 
   4098 #ifndef OPENSSL_NO_ENGINE
   4099     if (sctx->client_cert_engine) {
   4100         i = tls_engine_load_ssl_client_cert(s, px509, ppkey);
   4101         if (i != 0)
   4102             return i;
   4103     }
   4104 #endif
   4105     if (sctx->client_cert_cb)
   4106         i = sctx->client_cert_cb(SSL_CONNECTION_GET_USER_SSL(s), px509, ppkey);
   4107     return i;
   4108 }
   4109 
   4110 int ssl_cipher_list_to_bytes(SSL_CONNECTION *s, STACK_OF(SSL_CIPHER) *sk,
   4111     WPACKET *pkt)
   4112 {
   4113     int i;
   4114     size_t totlen = 0, len, maxlen, maxverok = 0;
   4115     int empty_reneg_info_scsv = !s->renegotiate
   4116         && !SSL_CONNECTION_IS_DTLS(s)
   4117         && ssl_security(s, SSL_SECOP_VERSION, 0, TLS1_VERSION, NULL)
   4118         && s->min_proto_version <= TLS1_VERSION;
   4119     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
   4120 
   4121     /* Set disabled masks for this session */
   4122     if (!ssl_set_client_disabled(s)) {
   4123         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_PROTOCOLS_AVAILABLE);
   4124         return 0;
   4125     }
   4126 
   4127     if (sk == NULL) {
   4128         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   4129         return 0;
   4130     }
   4131 
   4132 #ifdef OPENSSL_MAX_TLS1_2_CIPHER_LENGTH
   4133 #if OPENSSL_MAX_TLS1_2_CIPHER_LENGTH < 6
   4134 #error Max cipher length too short
   4135 #endif
   4136     /*
   4137      * Some servers hang if client hello > 256 bytes as hack workaround
   4138      * chop number of supported ciphers to keep it well below this if we
   4139      * use TLS v1.2
   4140      */
   4141     if (TLS1_get_version(ssl) >= TLS1_2_VERSION)
   4142         maxlen = OPENSSL_MAX_TLS1_2_CIPHER_LENGTH & ~1;
   4143     else
   4144 #endif
   4145         /* Maximum length that can be stored in 2 bytes. Length must be even */
   4146         maxlen = 0xfffe;
   4147 
   4148     if (empty_reneg_info_scsv)
   4149         maxlen -= 2;
   4150     if (s->mode & SSL_MODE_SEND_FALLBACK_SCSV)
   4151         maxlen -= 2;
   4152 
   4153     for (i = 0; i < sk_SSL_CIPHER_num(sk) && totlen < maxlen; i++) {
   4154         const SSL_CIPHER *c;
   4155 
   4156         c = sk_SSL_CIPHER_value(sk, i);
   4157         /* Skip disabled ciphers */
   4158         if (ssl_cipher_disabled(s, c, SSL_SECOP_CIPHER_SUPPORTED, 0))
   4159             continue;
   4160 
   4161         if (!ssl->method->put_cipher_by_char(c, pkt, &len)) {
   4162             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   4163             return 0;
   4164         }
   4165 
   4166         /* Sanity check that the maximum version we offer has ciphers enabled */
   4167         if (!maxverok) {
   4168             int minproto = SSL_CONNECTION_IS_DTLS(s) ? c->min_dtls : c->min_tls;
   4169             int maxproto = SSL_CONNECTION_IS_DTLS(s) ? c->max_dtls : c->max_tls;
   4170 
   4171             if (ssl_version_cmp(s, maxproto, s->s3.tmp.max_ver) >= 0
   4172                 && ssl_version_cmp(s, minproto, s->s3.tmp.max_ver) <= 0)
   4173                 maxverok = 1;
   4174         }
   4175 
   4176         totlen += len;
   4177     }
   4178 
   4179     if (totlen == 0 || !maxverok) {
   4180         const char *maxvertext = !maxverok
   4181             ? "No ciphers enabled for max supported SSL/TLS version"
   4182             : NULL;
   4183 
   4184         SSLfatal_data(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_CIPHERS_AVAILABLE,
   4185             maxvertext);
   4186         return 0;
   4187     }
   4188 
   4189     if (totlen != 0) {
   4190         if (empty_reneg_info_scsv) {
   4191             static const SSL_CIPHER scsv = {
   4192                 0, NULL, NULL, SSL3_CK_SCSV, 0, 0, 0, 0, 0, 0, 0, 0, 0
   4193             };
   4194             if (!ssl->method->put_cipher_by_char(&scsv, pkt, &len)) {
   4195                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   4196                 return 0;
   4197             }
   4198         }
   4199         if (s->mode & SSL_MODE_SEND_FALLBACK_SCSV) {
   4200             static const SSL_CIPHER scsv = {
   4201                 0, NULL, NULL, SSL3_CK_FALLBACK_SCSV, 0, 0, 0, 0, 0, 0, 0, 0, 0
   4202             };
   4203             if (!ssl->method->put_cipher_by_char(&scsv, pkt, &len)) {
   4204                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
   4205                 return 0;
   4206             }
   4207         }
   4208     }
   4209 
   4210     return 1;
   4211 }
   4212 
   4213 CON_FUNC_RETURN tls_construct_end_of_early_data(SSL_CONNECTION *s, WPACKET *pkt)
   4214 {
   4215     if (s->early_data_state != SSL_EARLY_DATA_WRITE_RETRY
   4216         && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING) {
   4217         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
   4218         return CON_FUNC_ERROR;
   4219     }
   4220 
   4221     s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
   4222     return CON_FUNC_SUCCESS;
   4223 }
   4224