text: /*
   * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
   * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
   * Copyright 2005 Nokia. All rights reserved.
   *
   * Licensed under the OpenSSL license (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #include <stdio.h>
  #include <time.h>
  #include <assert.h>
  #include "../ssl_local.h"
  #include "statem_local.h"
  #include <openssl/buffer.h>
  #include <openssl/rand.h>
  #include <openssl/objects.h>
  #include <openssl/evp.h>
  #include <openssl/md5.h>
  #include <openssl/dh.h>
  #include <openssl/bn.h>
  #include <openssl/engine.h>
  #include <internal/cryptlib.h>
  
  static MSG_PROCESS_RETURN tls_process_as_hello_retry_request(SSL *s, PACKET *pkt);
  static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL *s, PACKET *pkt);
  
  static ossl_inline int cert_req_allowed(SSL *s);
  static int key_exchange_expected(SSL *s);
  static int ssl_cipher_list_to_bytes(SSL *s, STACK_OF(SSL_CIPHER) *sk,
                                      WPACKET *pkt);
  
  /*
   * Is a CertificateRequest message allowed at the moment or not?
   *
   *  Return values are:
   *  1: Yes
   *  0: No
   */
  static ossl_inline int cert_req_allowed(SSL *s)
  {
      /* TLS does not like anon-DH with client cert */
      if ((s->version > SSL3_VERSION
           && (s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL))
          || (s->s3->tmp.new_cipher->algorithm_auth & (SSL_aSRP | SSL_aPSK)))
          return 0;
  
      return 1;
  }
  
  /*
   * Should we expect the ServerKeyExchange message or not?
   *
   *  Return values are:
   *  1: Yes
   *  0: No
   */
  static int key_exchange_expected(SSL *s)
  {
      long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
  
      /*
       * Can't skip server key exchange if this is an ephemeral
       * ciphersuite or for SRP
       */
      if (alg_k & (SSL_kDHE | SSL_kECDHE | SSL_kDHEPSK | SSL_kECDHEPSK
                   | SSL_kSRP)) {
          return 1;
      }
  
      return 0;
  }
  
  /*
   * ossl_statem_client_read_transition() encapsulates the logic for the allowed
   * handshake state transitions when a TLS1.3 client is reading messages from the
   * server. The message type that the server has sent is provided in |mt|. The
   * current state is in |s->statem.hand_state|.
   *
   * Return values are 1 for success (transition allowed) and  0 on error
   * (transition not allowed)
   */
  static int ossl_statem_client13_read_transition(SSL *s, int mt)
  {
      OSSL_STATEM *st = &s->statem;
  
      /*
       * Note: There is no case for TLS_ST_CW_CLNT_HELLO, because we haven't
       * yet negotiated TLSv1.3 at that point so that is handled by
       * ossl_statem_client_read_transition()
       */
  
      switch (st->hand_state) {
      default:
          break;
  
      case TLS_ST_CW_CLNT_HELLO:
          /*
           * This must a ClientHello following a HelloRetryRequest, so the only
           * thing we can get now is a ServerHello.
           */
          if (mt == SSL3_MT_SERVER_HELLO) {
              st->hand_state = TLS_ST_CR_SRVR_HELLO;
              return 1;
          }
          break;
  
      case TLS_ST_CR_SRVR_HELLO:
          if (mt == SSL3_MT_ENCRYPTED_EXTENSIONS) {
              st->hand_state = TLS_ST_CR_ENCRYPTED_EXTENSIONS;
              return 1;
          }
          break;
  
      case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
          if (s->hit) {
              if (mt == SSL3_MT_FINISHED) {
                  st->hand_state = TLS_ST_CR_FINISHED;
                  return 1;
              }
          } else {
              if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
                  st->hand_state = TLS_ST_CR_CERT_REQ;
                  return 1;
              }
              if (mt == SSL3_MT_CERTIFICATE) {
                  st->hand_state = TLS_ST_CR_CERT;
                  return 1;
              }
          }
          break;
  
      case TLS_ST_CR_CERT_REQ:
          if (mt == SSL3_MT_CERTIFICATE) {
              st->hand_state = TLS_ST_CR_CERT;
              return 1;
          }
          break;
  
      case TLS_ST_CR_CERT:
          if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
              st->hand_state = TLS_ST_CR_CERT_VRFY;
              return 1;
          }
          break;
  
      case TLS_ST_CR_CERT_VRFY:
          if (mt == SSL3_MT_FINISHED) {
              st->hand_state = TLS_ST_CR_FINISHED;
              return 1;
          }
          break;
  
      case TLS_ST_OK:
          if (mt == SSL3_MT_NEWSESSION_TICKET) {
              st->hand_state = TLS_ST_CR_SESSION_TICKET;
              return 1;
          }
          if (mt == SSL3_MT_KEY_UPDATE) {
              st->hand_state = TLS_ST_CR_KEY_UPDATE;
              return 1;
          }
          if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
  #if DTLS_MAX_VERSION != DTLS1_2_VERSION
  # error TODO(DTLS1.3): Restore digest for PHA before adding message.
  #endif
              if (!SSL_IS_DTLS(s) && s->post_handshake_auth == SSL_PHA_EXT_SENT) {
                  s->post_handshake_auth = SSL_PHA_REQUESTED;
                  /*
                   * In TLS, this is called before the message is added to the
                   * digest. In DTLS, this is expected to be called after adding
                   * to the digest. Either move the digest restore, or add the
                   * message here after the swap, or do it after the clientFinished?
                   */
                  if (!tls13_restore_handshake_digest_for_pha(s)) {
                      /* SSLfatal() already called */
                      return 0;
                  }
                  st->hand_state = TLS_ST_CR_CERT_REQ;
                  return 1;
              }
          }
          break;
      }
  
      /* No valid transition found */
      return 0;
  }
  
  /*
   * ossl_statem_client_read_transition() encapsulates the logic for the allowed
   * handshake state transitions when the client is reading messages from the
   * server. The message type that the server has sent is provided in |mt|. The
   * current state is in |s->statem.hand_state|.
   *
   * Return values are 1 for success (transition allowed) and  0 on error
   * (transition not allowed)
   */
  int ossl_statem_client_read_transition(SSL *s, int mt)
  {
      OSSL_STATEM *st = &s->statem;
      int ske_expected;
  
      /*
       * Note that after writing the first ClientHello we don't know what version
       * we are going to negotiate yet, so we don't take this branch until later.
       */
      if (SSL_IS_TLS13(s)) {
          if (!ossl_statem_client13_read_transition(s, mt))
              goto err;
          return 1;
      }
  
      switch (st->hand_state) {
      default:
          break;
  
      case TLS_ST_CW_CLNT_HELLO:
          if (mt == SSL3_MT_SERVER_HELLO) {
              st->hand_state = TLS_ST_CR_SRVR_HELLO;
              return 1;
          }
  
          if (SSL_IS_DTLS(s)) {
              if (mt == DTLS1_MT_HELLO_VERIFY_REQUEST) {
                  st->hand_state = DTLS_ST_CR_HELLO_VERIFY_REQUEST;
                  return 1;
              }
          }
          break;
  
      case TLS_ST_EARLY_DATA:
          /*
           * We've not actually selected TLSv1.3 yet, but we have sent early
           * data. The only thing allowed now is a ServerHello or a
           * HelloRetryRequest.
           */
          if (mt == SSL3_MT_SERVER_HELLO) {
              st->hand_state = TLS_ST_CR_SRVR_HELLO;
              return 1;
          }
          break;
  
      case TLS_ST_CR_SRVR_HELLO:
          if (s->hit) {
              if (s->ext.ticket_expected) {
                  if (mt == SSL3_MT_NEWSESSION_TICKET) {
                      st->hand_state = TLS_ST_CR_SESSION_TICKET;
                      return 1;
                  }
              } else if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
                  st->hand_state = TLS_ST_CR_CHANGE;
                  return 1;
              }
          } else {
              if (SSL_IS_DTLS(s) && mt == DTLS1_MT_HELLO_VERIFY_REQUEST) {
                  st->hand_state = DTLS_ST_CR_HELLO_VERIFY_REQUEST;
                  return 1;
              } else if (s->version >= TLS1_VERSION
                         && s->ext.session_secret_cb != NULL
                         && s->session->ext.tick != NULL
                         && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
                  /*
                   * Normally, we can tell if the server is resuming the session
                   * from the session ID. EAP-FAST (RFC 4851), however, relies on
                   * the next server message after the ServerHello to determine if
                   * the server is resuming.
                   */
                  s->hit = 1;
                  st->hand_state = TLS_ST_CR_CHANGE;
                  return 1;
              } else if (!(s->s3->tmp.new_cipher->algorithm_auth
                           & (SSL_aNULL | SSL_aSRP | SSL_aPSK))) {
                  if (mt == SSL3_MT_CERTIFICATE) {
                      st->hand_state = TLS_ST_CR_CERT;
                      return 1;
                  }
              } else {
                  ske_expected = key_exchange_expected(s);
                  /* SKE is optional for some PSK ciphersuites */
                  if (ske_expected
                      || ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_PSK)
                          && mt == SSL3_MT_SERVER_KEY_EXCHANGE)) {
                      if (mt == SSL3_MT_SERVER_KEY_EXCHANGE) {
                          st->hand_state = TLS_ST_CR_KEY_EXCH;
                          return 1;
                      }
                  } else if (mt == SSL3_MT_CERTIFICATE_REQUEST
                             && cert_req_allowed(s)) {
                      st->hand_state = TLS_ST_CR_CERT_REQ;
                      return 1;
                  } else if (mt == SSL3_MT_SERVER_DONE) {
                      st->hand_state = TLS_ST_CR_SRVR_DONE;
                      return 1;
                  }
              }
          }
          break;
  
      case TLS_ST_CR_CERT:
          /*
           * The CertificateStatus message is optional even if
           * |ext.status_expected| is set
           */
          if (s->ext.status_expected && mt == SSL3_MT_CERTIFICATE_STATUS) {
              st->hand_state = TLS_ST_CR_CERT_STATUS;
              return 1;
          }
          /* Fall through */
  
      case TLS_ST_CR_CERT_STATUS:
          ske_expected = key_exchange_expected(s);
          /* SKE is optional for some PSK ciphersuites */
          if (ske_expected || ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_PSK)
                               && mt == SSL3_MT_SERVER_KEY_EXCHANGE)) {
              if (mt == SSL3_MT_SERVER_KEY_EXCHANGE) {
                  st->hand_state = TLS_ST_CR_KEY_EXCH;
                  return 1;
              }
              goto err;
          }
          /* Fall through */
  
      case TLS_ST_CR_KEY_EXCH:
          if (mt == SSL3_MT_CERTIFICATE_REQUEST) {
              if (cert_req_allowed(s)) {
                  st->hand_state = TLS_ST_CR_CERT_REQ;
                  return 1;
              }
              goto err;
          }
          /* Fall through */
  
      case TLS_ST_CR_CERT_REQ:
          if (mt == SSL3_MT_SERVER_DONE) {
              st->hand_state = TLS_ST_CR_SRVR_DONE;
              return 1;
          }
          break;
  
      case TLS_ST_CW_FINISHED:
          if (s->ext.ticket_expected) {
              if (mt == SSL3_MT_NEWSESSION_TICKET) {
                  st->hand_state = TLS_ST_CR_SESSION_TICKET;
                  return 1;
              }
          } else if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
              st->hand_state = TLS_ST_CR_CHANGE;
              return 1;
          }
          break;
  
      case TLS_ST_CR_SESSION_TICKET:
          if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
              st->hand_state = TLS_ST_CR_CHANGE;
              return 1;
          }
          break;
  
      case TLS_ST_CR_CHANGE:
          if (mt == SSL3_MT_FINISHED) {
              st->hand_state = TLS_ST_CR_FINISHED;
              return 1;
          }
          break;
  
      case TLS_ST_OK:
          if (mt == SSL3_MT_HELLO_REQUEST) {
              st->hand_state = TLS_ST_CR_HELLO_REQ;
              return 1;
          }
          break;
      }
  
   err:
      /* No valid transition found */
      if (SSL_IS_DTLS(s) && mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
          BIO *rbio;
  
          /*
           * CCS messages don't have a message sequence number so this is probably
           * because of an out-of-order CCS. We'll just drop it.
           */
          s->init_num = 0;
          s->rwstate = SSL_READING;
          rbio = SSL_get_rbio(s);
          BIO_clear_retry_flags(rbio);
          BIO_set_retry_read(rbio);
          return 0;
      }
      SSLfatal(s, SSL3_AD_UNEXPECTED_MESSAGE,
               SSL_F_OSSL_STATEM_CLIENT_READ_TRANSITION,
               SSL_R_UNEXPECTED_MESSAGE);
      return 0;
  }
  
  /*
   * ossl_statem_client13_write_transition() works out what handshake state to
   * move to next when the TLSv1.3 client is writing messages to be sent to the
   * server.
   */
  static WRITE_TRAN ossl_statem_client13_write_transition(SSL *s)
  {
      OSSL_STATEM *st = &s->statem;
  
      /*
       * Note: There are no cases for TLS_ST_BEFORE because we haven't negotiated
       * TLSv1.3 yet at that point. They are handled by
       * ossl_statem_client_write_transition().
       */
      switch (st->hand_state) {
      default:
          /* Shouldn't happen */
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_OSSL_STATEM_CLIENT13_WRITE_TRANSITION,
                   ERR_R_INTERNAL_ERROR);
          return WRITE_TRAN_ERROR;
  
      case TLS_ST_CR_CERT_REQ:
          if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
              st->hand_state = TLS_ST_CW_CERT;
              return WRITE_TRAN_CONTINUE;
          }
          /*
           * We should only get here if we received a CertificateRequest after
           * we already sent close_notify
           */
          if (!ossl_assert((s->shutdown & SSL_SENT_SHUTDOWN) != 0)) {
              /* Shouldn't happen - same as default case */
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_OSSL_STATEM_CLIENT13_WRITE_TRANSITION,
                       ERR_R_INTERNAL_ERROR);
              return WRITE_TRAN_ERROR;
          }
          st->hand_state = TLS_ST_OK;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CR_FINISHED:
          if (s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY
                  || s->early_data_state == SSL_EARLY_DATA_FINISHED_WRITING)
              st->hand_state = TLS_ST_PENDING_EARLY_DATA_END;
          else if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
                   && s->hello_retry_request == SSL_HRR_NONE)
              st->hand_state = TLS_ST_CW_CHANGE;
          else
              st->hand_state = (s->s3->tmp.cert_req != 0) ? TLS_ST_CW_CERT
                                                          : TLS_ST_CW_FINISHED;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_PENDING_EARLY_DATA_END:
          if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED) {
              st->hand_state = TLS_ST_CW_END_OF_EARLY_DATA;
              return WRITE_TRAN_CONTINUE;
          }
          /* Fall through */
  
      case TLS_ST_CW_END_OF_EARLY_DATA:
      case TLS_ST_CW_CHANGE:
          st->hand_state = (s->s3->tmp.cert_req != 0) ? TLS_ST_CW_CERT
                                                      : TLS_ST_CW_FINISHED;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CW_CERT:
          /* If a non-empty Certificate we also send CertificateVerify */
          st->hand_state = (s->s3->tmp.cert_req == 1) ? TLS_ST_CW_CERT_VRFY
                                                      : TLS_ST_CW_FINISHED;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CW_CERT_VRFY:
          st->hand_state = TLS_ST_CW_FINISHED;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CR_KEY_UPDATE:
      case TLS_ST_CW_KEY_UPDATE:
      case TLS_ST_CR_SESSION_TICKET:
      case TLS_ST_CW_FINISHED:
          st->hand_state = TLS_ST_OK;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_OK:
          if (s->key_update != SSL_KEY_UPDATE_NONE) {
              st->hand_state = TLS_ST_CW_KEY_UPDATE;
              return WRITE_TRAN_CONTINUE;
          }
  
          /* Try to read from the server instead */
          return WRITE_TRAN_FINISHED;
      }
  }
  
  /*
   * ossl_statem_client_write_transition() works out what handshake state to
   * move to next when the client is writing messages to be sent to the server.
   */
  WRITE_TRAN ossl_statem_client_write_transition(SSL *s)
  {
      OSSL_STATEM *st = &s->statem;
  
      /*
       * Note that immediately before/after a ClientHello we don't know what
       * version we are going to negotiate yet, so we don't take this branch until
       * later
       */
      if (SSL_IS_TLS13(s))
          return ossl_statem_client13_write_transition(s);
  
      switch (st->hand_state) {
      default:
          /* Shouldn't happen */
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_OSSL_STATEM_CLIENT_WRITE_TRANSITION,
                   ERR_R_INTERNAL_ERROR);
          return WRITE_TRAN_ERROR;
  
      case TLS_ST_OK:
          if (!s->renegotiate) {
              /*
               * We haven't requested a renegotiation ourselves so we must have
               * received a message from the server. Better read it.
               */
              return WRITE_TRAN_FINISHED;
          }
          /* Renegotiation */
          /* fall thru */
      case TLS_ST_BEFORE:
          st->hand_state = TLS_ST_CW_CLNT_HELLO;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CW_CLNT_HELLO:
          if (s->early_data_state == SSL_EARLY_DATA_CONNECTING) {
              /*
               * We are assuming this is a TLSv1.3 connection, although we haven't
               * actually selected a version yet.
               */
              if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0)
                  st->hand_state = TLS_ST_CW_CHANGE;
              else
                  st->hand_state = TLS_ST_EARLY_DATA;
              return WRITE_TRAN_CONTINUE;
          }
          /*
           * No transition at the end of writing because we don't know what
           * we will be sent
           */
          return WRITE_TRAN_FINISHED;
  
      case TLS_ST_CR_SRVR_HELLO:
          /*
           * We only get here in TLSv1.3. We just received an HRR, so issue a
           * CCS unless middlebox compat mode is off, or we already issued one
           * because we did early data.
           */
          if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0
                  && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING)
              st->hand_state = TLS_ST_CW_CHANGE;
          else
              st->hand_state = TLS_ST_CW_CLNT_HELLO;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_EARLY_DATA:
          return WRITE_TRAN_FINISHED;
  
      case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
          st->hand_state = TLS_ST_CW_CLNT_HELLO;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CR_SRVR_DONE:
          if (s->s3->tmp.cert_req)
              st->hand_state = TLS_ST_CW_CERT;
          else
              st->hand_state = TLS_ST_CW_KEY_EXCH;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CW_CERT:
          st->hand_state = TLS_ST_CW_KEY_EXCH;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CW_KEY_EXCH:
          /*
           * For TLS, cert_req is set to 2, so a cert chain of nothing is
           * sent, but no verify packet is sent
           */
          /*
           * XXX: For now, we do not support client authentication in ECDH
           * cipher suites with ECDH (rather than ECDSA) certificates. We
           * need to skip the certificate verify message when client's
           * ECDH public key is sent inside the client certificate.
           */
          if (s->s3->tmp.cert_req == 1) {
              st->hand_state = TLS_ST_CW_CERT_VRFY;
          } else {
              st->hand_state = TLS_ST_CW_CHANGE;
          }
          if (s->s3->flags & TLS1_FLAGS_SKIP_CERT_VERIFY) {
              st->hand_state = TLS_ST_CW_CHANGE;
          }
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CW_CERT_VRFY:
          st->hand_state = TLS_ST_CW_CHANGE;
          return WRITE_TRAN_CONTINUE;
  
      case TLS_ST_CW_CHANGE:
          if (s->hello_retry_request == SSL_HRR_PENDING) {
              st->hand_state = TLS_ST_CW_CLNT_HELLO;
          } else if (s->early_data_state == SSL_EARLY_DATA_CONNECTING) {
              st->hand_state = TLS_ST_EARLY_DATA;
          } else {
  #if defined(OPENSSL_NO_NEXTPROTONEG)
              st->hand_state = TLS_ST_CW_FINISHED;
  #else
              if (!SSL_IS_DTLS(s) && s->s3->npn_seen)
                  st->hand_state = TLS_ST_CW_NEXT_PROTO;
              else
                  st->hand_state = TLS_ST_CW_FINISHED;
  #endif
          }
          return WRITE_TRAN_CONTINUE;
  
  #if !defined(OPENSSL_NO_NEXTPROTONEG)
      case TLS_ST_CW_NEXT_PROTO:
          st->hand_state = TLS_ST_CW_FINISHED;
          return WRITE_TRAN_CONTINUE;
  #endif
  
      case TLS_ST_CW_FINISHED:
          if (s->hit) {
              st->hand_state = TLS_ST_OK;
              return WRITE_TRAN_CONTINUE;
          } else {
              return WRITE_TRAN_FINISHED;
          }
  
      case TLS_ST_CR_FINISHED:
          if (s->hit) {
              st->hand_state = TLS_ST_CW_CHANGE;
              return WRITE_TRAN_CONTINUE;
          } else {
              st->hand_state = TLS_ST_OK;
              return WRITE_TRAN_CONTINUE;
          }
  
      case TLS_ST_CR_HELLO_REQ:
          /*
           * If we can renegotiate now then do so, otherwise wait for a more
           * convenient time.
           */
          if (ssl3_renegotiate_check(s, 1)) {
              if (!tls_setup_handshake(s)) {
                  /* SSLfatal() already called */
                  return WRITE_TRAN_ERROR;
              }
              st->hand_state = TLS_ST_CW_CLNT_HELLO;
              return WRITE_TRAN_CONTINUE;
          }
          st->hand_state = TLS_ST_OK;
          return WRITE_TRAN_CONTINUE;
      }
  }
  
  /*
   * Perform any pre work that needs to be done prior to sending a message from
   * the client to the server.
   */
  WORK_STATE ossl_statem_client_pre_work(SSL *s, WORK_STATE wst)
  {
      OSSL_STATEM *st = &s->statem;
  
      switch (st->hand_state) {
      default:
          /* No pre work to be done */
          break;
  
      case TLS_ST_CW_CLNT_HELLO:
          s->shutdown = 0;
          if (SSL_IS_DTLS(s)) {
              /* every DTLS ClientHello resets Finished MAC */
              if (!ssl3_init_finished_mac(s)) {
                  /* SSLfatal() already called */
                  return WORK_ERROR;
              }
          }
          break;
  
      case TLS_ST_CW_CHANGE:
          if (SSL_IS_DTLS(s)) {
              if (s->hit) {
                  /*
                   * We're into the last flight so we don't retransmit these
                   * messages unless we need to.
                   */
                  st->use_timer = 0;
              }
  #ifndef OPENSSL_NO_SCTP
              if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
                  /* Calls SSLfatal() as required */
                  return dtls_wait_for_dry(s);
              }
  #endif
          }
          break;
  
      case TLS_ST_PENDING_EARLY_DATA_END:
          /*
           * If we've been called by SSL_do_handshake()/SSL_write(), or we did not
           * attempt to write early data before calling SSL_read() then we press
           * on with the handshake. Otherwise we pause here.
           */
          if (s->early_data_state == SSL_EARLY_DATA_FINISHED_WRITING
                  || s->early_data_state == SSL_EARLY_DATA_NONE)
              return WORK_FINISHED_CONTINUE;
          /* Fall through */
  
      case TLS_ST_EARLY_DATA:
          return tls_finish_handshake(s, wst, 0, 1);
  
      case TLS_ST_OK:
          /* Calls SSLfatal() as required */
          return tls_finish_handshake(s, wst, 1, 1);
      }
  
      return WORK_FINISHED_CONTINUE;
  }
  
  /*
   * Perform any work that needs to be done after sending a message from the
   * client to the server.
   */
  WORK_STATE ossl_statem_client_post_work(SSL *s, WORK_STATE wst)
  {
      OSSL_STATEM *st = &s->statem;
  
      s->init_num = 0;
  
      switch (st->hand_state) {
      default:
          /* No post work to be done */
          break;
  
      case TLS_ST_CW_CLNT_HELLO:
          if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
                  && s->max_early_data > 0) {
              /*
               * We haven't selected TLSv1.3 yet so we don't call the change
               * cipher state function associated with the SSL_METHOD. Instead
               * we call tls13_change_cipher_state() directly.
               */
              if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) == 0) {
                  if (!tls13_change_cipher_state(s,
                              SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
                      /* SSLfatal() already called */
                      return WORK_ERROR;
                  }
              }
              /* else we're in compat mode so we delay flushing until after CCS */
          } else if (!statem_flush(s)) {
              return WORK_MORE_A;
          }
  
          if (SSL_IS_DTLS(s)) {
              /* Treat the next message as the first packet */
              s->first_packet = 1;
          }
          break;
  
      case TLS_ST_CW_END_OF_EARLY_DATA:
          /*
           * We set the enc_write_ctx back to NULL because we may end up writing
           * in cleartext again if we get a HelloRetryRequest from the server.
           */
          EVP_CIPHER_CTX_free(s->enc_write_ctx);
          s->enc_write_ctx = NULL;
          break;
  
      case TLS_ST_CW_KEY_EXCH:
          if (tls_client_key_exchange_post_work(s) == 0) {
              /* SSLfatal() already called */
              return WORK_ERROR;
          }
          break;
  
      case TLS_ST_CW_CHANGE:
          if (SSL_IS_TLS13(s) || s->hello_retry_request == SSL_HRR_PENDING)
              break;
          if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
                      && s->max_early_data > 0) {
              /*
               * We haven't selected TLSv1.3 yet so we don't call the change
               * cipher state function associated with the SSL_METHOD. Instead
               * we call tls13_change_cipher_state() directly.
               */
              if (!tls13_change_cipher_state(s,
                          SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_CLIENT_WRITE))
                  return WORK_ERROR;
              break;
          }
          s->session->cipher = s->s3->tmp.new_cipher;
  #ifdef OPENSSL_NO_COMP
          s->session->compress_meth = 0;
  #else
          if (s->s3->tmp.new_compression == NULL)
              s->session->compress_meth = 0;
          else
              s->session->compress_meth = s->s3->tmp.new_compression->id;
  #endif
          if (!s->method->ssl3_enc->setup_key_block(s)) {
              /* SSLfatal() already called */
              return WORK_ERROR;
          }
  
          if (!s->method->ssl3_enc->change_cipher_state(s,
                                            SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
              /* SSLfatal() already called */
              return WORK_ERROR;
          }
  
          if (SSL_IS_DTLS(s)) {
  #ifndef OPENSSL_NO_SCTP
              if (s->hit) {
                  /*
                   * Change to new shared key of SCTP-Auth, will be ignored if
                   * no SCTP used.
                   */
                  BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
                           0, NULL);
              }
  #endif
  
              dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
          }
          break;
  
      case TLS_ST_CW_FINISHED:
  #ifndef OPENSSL_NO_SCTP
          if (wst == WORK_MORE_A && SSL_IS_DTLS(s) && s->hit == 0) {
              /*
               * Change to new shared key of SCTP-Auth, will be ignored if
               * no SCTP used.
               */
              BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
                       0, NULL);
          }
  #endif
          if (statem_flush(s) != 1)
              return WORK_MORE_B;
  
          if (SSL_IS_TLS13(s)) {
              if (!tls13_save_handshake_digest_for_pha(s)) {
                  /* SSLfatal() already called */
                  return WORK_ERROR;
              }
              if (s->post_handshake_auth != SSL_PHA_REQUESTED) {
                  if (!s->method->ssl3_enc->change_cipher_state(s,
                          SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
                      /* SSLfatal() already called */
                      return WORK_ERROR;
                  }
              }
          }
          break;
  
      case TLS_ST_CW_KEY_UPDATE:
          if (statem_flush(s) != 1)
              return WORK_MORE_A;
          if (!tls13_update_key(s, 1)) {
              /* SSLfatal() already called */
              return WORK_ERROR;
          }
          break;
      }
  
      return WORK_FINISHED_CONTINUE;
  }
  
  /*
   * Get the message construction function and message type for sending from the
   * client
   *
   * Valid return values are:
   *   1: Success
   *   0: Error
   */
  int ossl_statem_client_construct_message(SSL *s, WPACKET *pkt,
                                           confunc_f *confunc, int *mt)
  {
      OSSL_STATEM *st = &s->statem;
  
      switch (st->hand_state) {
      default:
          /* Shouldn't happen */
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_OSSL_STATEM_CLIENT_CONSTRUCT_MESSAGE,
                   SSL_R_BAD_HANDSHAKE_STATE);
          return 0;
  
      case TLS_ST_CW_CHANGE:
          if (SSL_IS_DTLS(s))
              *confunc = dtls_construct_change_cipher_spec;
          else
              *confunc = tls_construct_change_cipher_spec;
          *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
          break;
  
      case TLS_ST_CW_CLNT_HELLO:
          *confunc = tls_construct_client_hello;
          *mt = SSL3_MT_CLIENT_HELLO;
          break;
  
      case TLS_ST_CW_END_OF_EARLY_DATA:
          *confunc = tls_construct_end_of_early_data;
          *mt = SSL3_MT_END_OF_EARLY_DATA;
          break;
  
      case TLS_ST_PENDING_EARLY_DATA_END:
          *confunc = NULL;
          *mt = SSL3_MT_DUMMY;
          break;
  
      case TLS_ST_CW_CERT:
          *confunc = tls_construct_client_certificate;
          *mt = SSL3_MT_CERTIFICATE;
          break;
  
      case TLS_ST_CW_KEY_EXCH:
          *confunc = tls_construct_client_key_exchange;
          *mt = SSL3_MT_CLIENT_KEY_EXCHANGE;
          break;
  
      case TLS_ST_CW_CERT_VRFY:
          *confunc = tls_construct_cert_verify;
          *mt = SSL3_MT_CERTIFICATE_VERIFY;
          break;
  
  #if !defined(OPENSSL_NO_NEXTPROTONEG)
      case TLS_ST_CW_NEXT_PROTO:
          *confunc = tls_construct_next_proto;
          *mt = SSL3_MT_NEXT_PROTO;
          break;
  #endif
      case TLS_ST_CW_FINISHED:
          *confunc = tls_construct_finished;
          *mt = SSL3_MT_FINISHED;
          break;
  
      case TLS_ST_CW_KEY_UPDATE:
          *confunc = tls_construct_key_update;
          *mt = SSL3_MT_KEY_UPDATE;
          break;
      }
  
      return 1;
  }
  
  /*
   * Returns the maximum allowed length for the current message that we are
   * reading. Excludes the message header.
   */
  size_t ossl_statem_client_max_message_size(SSL *s)
  {
      OSSL_STATEM *st = &s->statem;
  
      switch (st->hand_state) {
      default:
          /* Shouldn't happen */
          return 0;
  
      case TLS_ST_CR_SRVR_HELLO:
          return SERVER_HELLO_MAX_LENGTH;
  
      case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
          return HELLO_VERIFY_REQUEST_MAX_LENGTH;
  
      case TLS_ST_CR_CERT:
          return s->max_cert_list;
  
      case TLS_ST_CR_CERT_VRFY:
          return SSL3_RT_MAX_PLAIN_LENGTH;
  
      case TLS_ST_CR_CERT_STATUS:
          return SSL3_RT_MAX_PLAIN_LENGTH;
  
      case TLS_ST_CR_KEY_EXCH:
          return SERVER_KEY_EXCH_MAX_LENGTH;
  
      case TLS_ST_CR_CERT_REQ:
          /*
           * Set to s->max_cert_list for compatibility with previous releases. In
           * practice these messages can get quite long if servers are configured
           * to provide a long list of acceptable CAs
           */
          return s->max_cert_list;
  
      case TLS_ST_CR_SRVR_DONE:
          return SERVER_HELLO_DONE_MAX_LENGTH;
  
      case TLS_ST_CR_CHANGE:
          if (s->version == DTLS1_BAD_VER)
              return 3;
          return CCS_MAX_LENGTH;
  
      case TLS_ST_CR_SESSION_TICKET:
          return (SSL_IS_TLS13(s)) ? SESSION_TICKET_MAX_LENGTH_TLS13
                                   : SESSION_TICKET_MAX_LENGTH_TLS12;
  
      case TLS_ST_CR_FINISHED:
          return FINISHED_MAX_LENGTH;
  
      case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
          return ENCRYPTED_EXTENSIONS_MAX_LENGTH;
  
      case TLS_ST_CR_KEY_UPDATE:
          return KEY_UPDATE_MAX_LENGTH;
      }
  }
  
  /*
   * Process a message that the client has been received from the server.
   */
  MSG_PROCESS_RETURN ossl_statem_client_process_message(SSL *s, PACKET *pkt)
  {
      OSSL_STATEM *st = &s->statem;
  
      switch (st->hand_state) {
      default:
          /* Shouldn't happen */
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_OSSL_STATEM_CLIENT_PROCESS_MESSAGE,
                   ERR_R_INTERNAL_ERROR);
          return MSG_PROCESS_ERROR;
  
      case TLS_ST_CR_SRVR_HELLO:
          return tls_process_server_hello(s, pkt);
  
      case DTLS_ST_CR_HELLO_VERIFY_REQUEST:
          return dtls_process_hello_verify(s, pkt);
  
      case TLS_ST_CR_CERT:
          return tls_process_server_certificate(s, pkt);
  
      case TLS_ST_CR_CERT_VRFY:
          return tls_process_cert_verify(s, pkt);
  
      case TLS_ST_CR_CERT_STATUS:
          return tls_process_cert_status(s, pkt);
  
      case TLS_ST_CR_KEY_EXCH:
          return tls_process_key_exchange(s, pkt);
  
      case TLS_ST_CR_CERT_REQ:
          return tls_process_certificate_request(s, pkt);
  
      case TLS_ST_CR_SRVR_DONE:
          return tls_process_server_done(s, pkt);
  
      case TLS_ST_CR_CHANGE:
          return tls_process_change_cipher_spec(s, pkt);
  
      case TLS_ST_CR_SESSION_TICKET:
          return tls_process_new_session_ticket(s, pkt);
  
      case TLS_ST_CR_FINISHED:
          return tls_process_finished(s, pkt);
  
      case TLS_ST_CR_HELLO_REQ:
          return tls_process_hello_req(s, pkt);
  
      case TLS_ST_CR_ENCRYPTED_EXTENSIONS:
          return tls_process_encrypted_extensions(s, pkt);
  
      case TLS_ST_CR_KEY_UPDATE:
          return tls_process_key_update(s, pkt);
      }
  }
  
  /*
   * Perform any further processing required following the receipt of a message
   * from the server
   */
  WORK_STATE ossl_statem_client_post_process_message(SSL *s, WORK_STATE wst)
  {
      OSSL_STATEM *st = &s->statem;
  
      switch (st->hand_state) {
      default:
          /* Shouldn't happen */
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_OSSL_STATEM_CLIENT_POST_PROCESS_MESSAGE,
                   ERR_R_INTERNAL_ERROR);
          return WORK_ERROR;
  
      case TLS_ST_CR_CERT_VRFY:
      case TLS_ST_CR_CERT_REQ:
          return tls_prepare_client_certificate(s, wst);
      }
  }
  
  int tls_construct_client_hello(SSL *s, WPACKET *pkt)
  {
      unsigned char *p;
      size_t sess_id_len;
      int i, protverr;
  #ifndef OPENSSL_NO_COMP
      SSL_COMP *comp;
  #endif
      SSL_SESSION *sess = s->session;
      unsigned char *session_id;
  
      /* Work out what SSL/TLS/DTLS version to use */
      protverr = ssl_set_client_hello_version(s);
      if (protverr != 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                   protverr);
          return 0;
      }
  
      if (sess == NULL
              || !ssl_version_supported(s, sess->ssl_version, NULL)
              || !SSL_SESSION_is_resumable(sess)) {
          if (s->hello_retry_request == SSL_HRR_NONE
                  && !ssl_get_new_session(s, 0)) {
              /* SSLfatal() already called */
              return 0;
          }
      }
      /* else use the pre-loaded session */
  
      p = s->s3->client_random;
  
      /*
       * for DTLS if client_random is initialized, reuse it, we are
       * required to use same upon reply to HelloVerify
       */
      if (SSL_IS_DTLS(s)) {
          size_t idx;
          i = 1;
          for (idx = 0; idx < sizeof(s->s3->client_random); idx++) {
              if (p[idx]) {
                  i = 0;
                  break;
              }
          }
      } else {
          i = (s->hello_retry_request == SSL_HRR_NONE);
      }
  
      if (i && ssl_fill_hello_random(s, 0, p, sizeof(s->s3->client_random),
                                     DOWNGRADE_NONE) <= 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      /*-
       * version indicates the negotiated version: for example from
       * an SSLv2/v3 compatible client hello). The client_version
       * field is the maximum version we permit and it is also
       * used in RSA encrypted premaster secrets. Some servers can
       * choke if we initially report a higher version then
       * renegotiate to a lower one in the premaster secret. This
       * didn't happen with TLS 1.0 as most servers supported it
       * but it can with TLS 1.1 or later if the server only supports
       * 1.0.
       *
       * Possible scenario with previous logic:
       *      1. Client hello indicates TLS 1.2
       *      2. Server hello says TLS 1.0
       *      3. RSA encrypted premaster secret uses 1.2.
       *      4. Handshake proceeds using TLS 1.0.
       *      5. Server sends hello request to renegotiate.
       *      6. Client hello indicates TLS v1.0 as we now
       *         know that is maximum server supports.
       *      7. Server chokes on RSA encrypted premaster secret
       *         containing version 1.0.
       *
       * For interoperability it should be OK to always use the
       * maximum version we support in client hello and then rely
       * on the checking of version to ensure the servers isn't
       * being inconsistent: for example initially negotiating with
       * TLS 1.0 and renegotiating with TLS 1.2. We do this by using
       * client_version in client hello and not resetting it to
       * the negotiated version.
       *
       * For TLS 1.3 we always set the ClientHello version to 1.2 and rely on the
       * supported_versions extension for the real supported versions.
       */
      if (!WPACKET_put_bytes_u16(pkt, s->client_version)
              || !WPACKET_memcpy(pkt, s->s3->client_random, SSL3_RANDOM_SIZE)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      /* Session ID */
      session_id = s->session->session_id;
      if (s->new_session || s->session->ssl_version == TLS1_3_VERSION) {
          if (s->version == TLS1_3_VERSION
                  && (s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0) {
              sess_id_len = sizeof(s->tmp_session_id);
              s->tmp_session_id_len = sess_id_len;
              session_id = s->tmp_session_id;
              if (s->hello_retry_request == SSL_HRR_NONE
                      && RAND_bytes(s->tmp_session_id, sess_id_len) <= 0) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                           ERR_R_INTERNAL_ERROR);
                  return 0;
              }
          } else {
              sess_id_len = 0;
          }
      } else {
          assert(s->session->session_id_length <= sizeof(s->session->session_id));
          sess_id_len = s->session->session_id_length;
          if (s->version == TLS1_3_VERSION) {
              s->tmp_session_id_len = sess_id_len;
              memcpy(s->tmp_session_id, s->session->session_id, sess_id_len);
          }
      }
      if (!WPACKET_start_sub_packet_u8(pkt)
              || (sess_id_len != 0 && !WPACKET_memcpy(pkt, session_id,
                                                      sess_id_len))
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      /* cookie stuff for DTLS */
      if (SSL_IS_DTLS(s)) {
          if (s->d1->cookie_len > sizeof(s->d1->cookie)
                  || !WPACKET_sub_memcpy_u8(pkt, s->d1->cookie,
                                            s->d1->cookie_len)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                       ERR_R_INTERNAL_ERROR);
              return 0;
          }
      }
  
      /* Ciphers supported */
      if (!WPACKET_start_sub_packet_u16(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      if (!ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s), pkt)) {
          /* SSLfatal() already called */
          return 0;
      }
      if (!WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      /* COMPRESSION */
      if (!WPACKET_start_sub_packet_u8(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  #ifndef OPENSSL_NO_COMP
      if (ssl_allow_compression(s)
              && s->ctx->comp_methods
              && (SSL_IS_DTLS(s) || s->s3->tmp.max_ver < TLS1_3_VERSION)) {
          int compnum = sk_SSL_COMP_num(s->ctx->comp_methods);
          for (i = 0; i < compnum; i++) {
              comp = sk_SSL_COMP_value(s->ctx->comp_methods, i);
              if (!WPACKET_put_bytes_u8(pkt, comp->id)) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                           ERR_R_INTERNAL_ERROR);
                  return 0;
              }
          }
      }
  #endif
      /* Add the NULL method */
      if (!WPACKET_put_bytes_u8(pkt, 0) || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CLIENT_HELLO,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      /* TLS extensions */
      if (!tls_construct_extensions(s, pkt, SSL_EXT_CLIENT_HELLO, NULL, 0)) {
          /* SSLfatal() already called */
          return 0;
      }
  
      return 1;
  }
  
  MSG_PROCESS_RETURN dtls_process_hello_verify(SSL *s, PACKET *pkt)
  {
      size_t cookie_len;
      PACKET cookiepkt;
  
      if (!PACKET_forward(pkt, 2)
          || !PACKET_get_length_prefixed_1(pkt, &cookiepkt)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_DTLS_PROCESS_HELLO_VERIFY,
                   SSL_R_LENGTH_MISMATCH);
          return MSG_PROCESS_ERROR;
      }
  
      cookie_len = PACKET_remaining(&cookiepkt);
      if (cookie_len > sizeof(s->d1->cookie)) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_DTLS_PROCESS_HELLO_VERIFY,
                   SSL_R_LENGTH_TOO_LONG);
          return MSG_PROCESS_ERROR;
      }
  
      if (!PACKET_copy_bytes(&cookiepkt, s->d1->cookie, cookie_len)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_DTLS_PROCESS_HELLO_VERIFY,
                   SSL_R_LENGTH_MISMATCH);
          return MSG_PROCESS_ERROR;
      }
      s->d1->cookie_len = cookie_len;
  
      return MSG_PROCESS_FINISHED_READING;
  }
  
  static int set_client_ciphersuite(SSL *s, const unsigned char *cipherchars)
  {
      STACK_OF(SSL_CIPHER) *sk;
      const SSL_CIPHER *c;
      int i;
  
      c = ssl_get_cipher_by_char(s, cipherchars, 0);
      if (c == NULL) {
          /* unknown cipher */
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_SET_CLIENT_CIPHERSUITE,
                   SSL_R_UNKNOWN_CIPHER_RETURNED);
          return 0;
      }
      /*
       * If it is a disabled cipher we either didn't send it in client hello,
       * or it's not allowed for the selected protocol. So we return an error.
       */
      if (ssl_cipher_disabled(s, c, SSL_SECOP_CIPHER_CHECK, 1)) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_SET_CLIENT_CIPHERSUITE,
                   SSL_R_WRONG_CIPHER_RETURNED);
          return 0;
      }
  
      sk = ssl_get_ciphers_by_id(s);
      i = sk_SSL_CIPHER_find(sk, c);
      if (i < 0) {
          /* we did not say we would use this cipher */
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_SET_CLIENT_CIPHERSUITE,
                   SSL_R_WRONG_CIPHER_RETURNED);
          return 0;
      }
  
      if (SSL_IS_TLS13(s) && s->s3->tmp.new_cipher != NULL
              && s->s3->tmp.new_cipher->id != c->id) {
          /* ServerHello selected a different ciphersuite to that in the HRR */
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_SET_CLIENT_CIPHERSUITE,
                   SSL_R_WRONG_CIPHER_RETURNED);
          return 0;
      }
  
      /*
       * Depending on the session caching (internal/external), the cipher
       * and/or cipher_id values may not be set. Make sure that cipher_id is
       * set and use it for comparison.
       */
      if (s->session->cipher != NULL)
          s->session->cipher_id = s->session->cipher->id;
      if (s->hit && (s->session->cipher_id != c->id)) {
          if (SSL_IS_TLS13(s)) {
              /*
               * In TLSv1.3 it is valid for the server to select a different
               * ciphersuite as long as the hash is the same.
               */
              if (ssl_md(c->algorithm2)
                      != ssl_md(s->session->cipher->algorithm2)) {
                  SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                           SSL_F_SET_CLIENT_CIPHERSUITE,
                           SSL_R_CIPHERSUITE_DIGEST_HAS_CHANGED);
                  return 0;
              }
          } else {
              /*
               * Prior to TLSv1.3 resuming a session always meant using the same
               * ciphersuite.
               */
              SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_SET_CLIENT_CIPHERSUITE,
                       SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED);
              return 0;
          }
      }
      s->s3->tmp.new_cipher = c;
  
      return 1;
  }
  
  MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt)
  {
      PACKET session_id, extpkt;
      size_t session_id_len;
      const unsigned char *cipherchars;
      int hrr = 0;
      unsigned int compression;
      unsigned int sversion;
      unsigned int context;
      RAW_EXTENSION *extensions = NULL;
  #ifndef OPENSSL_NO_COMP
      SSL_COMP *comp;
  #endif
  
      if (!PACKET_get_net_2(pkt, &sversion)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_LENGTH_MISMATCH);
          goto err;
      }
  
      /* load the server random */
      if (s->version == TLS1_3_VERSION
              && sversion == TLS1_2_VERSION
              && PACKET_remaining(pkt) >= SSL3_RANDOM_SIZE
              && memcmp(hrrrandom, PACKET_data(pkt), SSL3_RANDOM_SIZE) == 0) {
          s->hello_retry_request = SSL_HRR_PENDING;
          hrr = 1;
          if (!PACKET_forward(pkt, SSL3_RANDOM_SIZE)) {
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_HELLO,
                       SSL_R_LENGTH_MISMATCH);
              goto err;
          }
      } else {
          if (!PACKET_copy_bytes(pkt, s->s3->server_random, SSL3_RANDOM_SIZE)) {
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_HELLO,
                       SSL_R_LENGTH_MISMATCH);
              goto err;
          }
      }
  
      /* Get the session-id. */
      if (!PACKET_get_length_prefixed_1(pkt, &session_id)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_LENGTH_MISMATCH);
          goto err;
      }
      session_id_len = PACKET_remaining(&session_id);
      if (session_id_len > sizeof(s->session->session_id)
          || session_id_len > SSL3_SESSION_ID_SIZE) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_SSL3_SESSION_ID_TOO_LONG);
          goto err;
      }
  
      if (!PACKET_get_bytes(pkt, &cipherchars, TLS_CIPHER_LEN)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_LENGTH_MISMATCH);
          goto err;
      }
  
      if (!PACKET_get_1(pkt, &compression)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_LENGTH_MISMATCH);
          goto err;
      }
  
      /* TLS extensions */
      if (PACKET_remaining(pkt) == 0 && !hrr) {
          PACKET_null_init(&extpkt);
      } else if (!PACKET_as_length_prefixed_2(pkt, &extpkt)
                 || PACKET_remaining(pkt) != 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_BAD_LENGTH);
          goto err;
      }
  
      if (!hrr) {
          if (!tls_collect_extensions(s, &extpkt,
                                      SSL_EXT_TLS1_2_SERVER_HELLO
                                      | SSL_EXT_TLS1_3_SERVER_HELLO,
                                      &extensions, NULL, 1)) {
              /* SSLfatal() already called */
              goto err;
          }
  
          if (!ssl_choose_client_version(s, sversion, extensions)) {
              /* SSLfatal() already called */
              goto err;
          }
      }
  
      if (SSL_IS_TLS13(s) || hrr) {
          if (compression != 0) {
              SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                       SSL_F_TLS_PROCESS_SERVER_HELLO,
                       SSL_R_INVALID_COMPRESSION_ALGORITHM);
              goto err;
          }
  
          if (session_id_len != s->tmp_session_id_len
                  || memcmp(PACKET_data(&session_id), s->tmp_session_id,
                            session_id_len) != 0) {
              SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                       SSL_F_TLS_PROCESS_SERVER_HELLO, SSL_R_INVALID_SESSION_ID);
              goto err;
          }
      }
  
      if (hrr) {
          if (!set_client_ciphersuite(s, cipherchars)) {
              /* SSLfatal() already called */
              goto err;
          }
  
          return tls_process_as_hello_retry_request(s, &extpkt);
      }
  
      /*
       * Now we have chosen the version we need to check again that the extensions
       * are appropriate for this version.
       */
      context = SSL_IS_TLS13(s) ? SSL_EXT_TLS1_3_SERVER_HELLO
                                : SSL_EXT_TLS1_2_SERVER_HELLO;
      if (!tls_validate_all_contexts(s, context, extensions)) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_BAD_EXTENSION);
          goto err;
      }
  
      s->hit = 0;
  
      if (SSL_IS_TLS13(s)) {
          /*
           * In TLSv1.3 a ServerHello message signals a key change so the end of
           * the message must be on a record boundary.
           */
          if (RECORD_LAYER_processed_read_pending(&s->rlayer)) {
              SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
                       SSL_F_TLS_PROCESS_SERVER_HELLO,
                       SSL_R_NOT_ON_RECORD_BOUNDARY);
              goto err;
          }
  
          /* This will set s->hit if we are resuming */
          if (!tls_parse_extension(s, TLSEXT_IDX_psk,
                                   SSL_EXT_TLS1_3_SERVER_HELLO,
                                   extensions, NULL, 0)) {
              /* SSLfatal() already called */
              goto err;
          }
      } else {
          /*
           * Check if we can resume the session based on external pre-shared
           * secret. EAP-FAST (RFC 4851) supports two types of session resumption.
           * Resumption based on server-side state works with session IDs.
           * Resumption based on pre-shared Protected Access Credentials (PACs)
           * works by overriding the SessionTicket extension at the application
           * layer, and does not send a session ID. (We do not know whether
           * EAP-FAST servers would honour the session ID.) Therefore, the session
           * ID alone is not a reliable indicator of session resumption, so we
           * first check if we can resume, and later peek at the next handshake
           * message to see if the server wants to resume.
           */
          if (s->version >= TLS1_VERSION
                  && s->ext.session_secret_cb != NULL && s->session->ext.tick) {
              const SSL_CIPHER *pref_cipher = NULL;
              /*
               * s->session->master_key_length is a size_t, but this is an int for
               * backwards compat reasons
               */
              int master_key_length;
              master_key_length = sizeof(s->session->master_key);
              if (s->ext.session_secret_cb(s, s->session->master_key,
                                           &master_key_length,
                                           NULL, &pref_cipher,
                                           s->ext.session_secret_cb_arg)
                       && master_key_length > 0) {
                  s->session->master_key_length = master_key_length;
                  s->session->cipher = pref_cipher ?
                      pref_cipher : ssl_get_cipher_by_char(s, cipherchars, 0);
              } else {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_PROCESS_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
                  goto err;
              }
          }
  
          if (session_id_len != 0
                  && session_id_len == s->session->session_id_length
                  && memcmp(PACKET_data(&session_id), s->session->session_id,
                            session_id_len) == 0)
              s->hit = 1;
      }
  
      if (s->hit) {
          if (s->sid_ctx_length != s->session->sid_ctx_length
                  || memcmp(s->session->sid_ctx, s->sid_ctx, s->sid_ctx_length)) {
              /* actually a client application bug */
              SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                       SSL_F_TLS_PROCESS_SERVER_HELLO,
                       SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
              goto err;
          }
      } else {
          /*
           * If we were trying for session-id reuse but the server
           * didn't resume, make a new SSL_SESSION.
           * In the case of EAP-FAST and PAC, we do not send a session ID,
           * so the PAC-based session secret is always preserved. It'll be
           * overwritten if the server refuses resumption.
           */
          if (s->session->session_id_length > 0) {
              tsan_counter(&s->session_ctx->stats.sess_miss);
              if (!ssl_get_new_session(s, 0)) {
                  /* SSLfatal() already called */
                  goto err;
              }
          }
  
          s->session->ssl_version = s->version;
          /*
           * In TLSv1.2 and below we save the session id we were sent so we can
           * resume it later. In TLSv1.3 the session id we were sent is just an
           * echo of what we originally sent in the ClientHello and should not be
           * used for resumption.
           */
          if (!SSL_IS_TLS13(s)) {
              s->session->session_id_length = session_id_len;
              /* session_id_len could be 0 */
              if (session_id_len > 0)
                  memcpy(s->session->session_id, PACKET_data(&session_id),
                         session_id_len);
          }
      }
  
      /* Session version and negotiated protocol version should match */
      if (s->version != s->session->ssl_version) {
          SSLfatal(s, SSL_AD_PROTOCOL_VERSION, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_SSL_SESSION_VERSION_MISMATCH);
          goto err;
      }
      /*
       * Now that we know the version, update the check to see if it's an allowed
       * version.
       */
      s->s3->tmp.min_ver = s->version;
      s->s3->tmp.max_ver = s->version;
  
      if (!set_client_ciphersuite(s, cipherchars)) {
          /* SSLfatal() already called */
          goto err;
      }
  
  #ifdef OPENSSL_NO_COMP
      if (compression != 0) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
          goto err;
      }
      /*
       * If compression is disabled we'd better not try to resume a session
       * using compression.
       */
      if (s->session->compress_meth != 0) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_INCONSISTENT_COMPRESSION);
          goto err;
      }
  #else
      if (s->hit && compression != s->session->compress_meth) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_OLD_SESSION_COMPRESSION_ALGORITHM_NOT_RETURNED);
          goto err;
      }
      if (compression == 0)
          comp = NULL;
      else if (!ssl_allow_compression(s)) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_COMPRESSION_DISABLED);
          goto err;
      } else {
          comp = ssl3_comp_find(s->ctx->comp_methods, compression);
      }
  
      if (compression != 0 && comp == NULL) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SERVER_HELLO,
                   SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
          goto err;
      } else {
          s->s3->tmp.new_compression = comp;
      }
  #endif
  
      if (!tls_parse_all_extensions(s, context, extensions, NULL, 0, 1)) {
          /* SSLfatal() already called */
          goto err;
      }
  
  #ifndef OPENSSL_NO_SCTP
      if (SSL_IS_DTLS(s) && s->hit) {
          unsigned char sctpauthkey[64];
          char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
          size_t labellen;
  
          /*
           * Add new shared key for SCTP-Auth, will be ignored if
           * no SCTP used.
           */
          memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
                 sizeof(DTLS1_SCTP_AUTH_LABEL));
  
          /* Don't include the terminating zero. */
          labellen = sizeof(labelbuffer) - 1;
          if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
              labellen += 1;
  
          if (SSL_export_keying_material(s, sctpauthkey,
                                         sizeof(sctpauthkey),
                                         labelbuffer,
                                         labellen, NULL, 0, 0) <= 0) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SERVER_HELLO,
                       ERR_R_INTERNAL_ERROR);
              goto err;
          }
  
          BIO_ctrl(SSL_get_wbio(s),
                   BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
                   sizeof(sctpauthkey), sctpauthkey);
      }
  #endif
  
      /*
       * In TLSv1.3 we have some post-processing to change cipher state, otherwise
       * we're done with this message
       */
      if (SSL_IS_TLS13(s)
              && (!s->method->ssl3_enc->setup_key_block(s)
                  || !s->method->ssl3_enc->change_cipher_state(s,
                      SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_READ))) {
          /* SSLfatal() already called */
          goto err;
      }
  
      OPENSSL_free(extensions);
      return MSG_PROCESS_CONTINUE_READING;
   err:
      OPENSSL_free(extensions);
      return MSG_PROCESS_ERROR;
  }
  
  static MSG_PROCESS_RETURN tls_process_as_hello_retry_request(SSL *s,
                                                               PACKET *extpkt)
  {
      RAW_EXTENSION *extensions = NULL;
  
      /*
       * If we were sending early_data then the enc_write_ctx is now invalid and
       * should not be used.
       */
      EVP_CIPHER_CTX_free(s->enc_write_ctx);
      s->enc_write_ctx = NULL;
  
      if (!tls_collect_extensions(s, extpkt, SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST,
                                  &extensions, NULL, 1)
              || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST,
                                           extensions, NULL, 0, 1)) {
          /* SSLfatal() already called */
          goto err;
      }
  
      OPENSSL_free(extensions);
      extensions = NULL;
  
      if (s->ext.tls13_cookie_len == 0
  #if !defined(OPENSSL_NO_EC) || !defined(OPENSSL_NO_DH)
          && s->s3->tmp.pkey != NULL
  #endif
          ) {
          /*
           * We didn't receive a cookie or a new key_share so the next
           * ClientHello will not change
           */
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                   SSL_F_TLS_PROCESS_AS_HELLO_RETRY_REQUEST,
                   SSL_R_NO_CHANGE_FOLLOWING_HRR);
          goto err;
      }
  
      /*
       * Re-initialise the Transcript Hash. We're going to prepopulate it with
       * a synthetic message_hash in place of ClientHello1.
       */
      if (!create_synthetic_message_hash(s, NULL, 0, NULL, 0)) {
          /* SSLfatal() already called */
          goto err;
      }
  
      /*
       * Add this message to the Transcript Hash. Normally this is done
       * automatically prior to the message processing stage. However due to the
       * need to create the synthetic message hash, we defer that step until now
       * for HRR messages.
       */
      if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
                                  s->init_num + SSL3_HM_HEADER_LENGTH)) {
          /* SSLfatal() already called */
          goto err;
      }
  
      return MSG_PROCESS_FINISHED_READING;
   err:
      OPENSSL_free(extensions);
      return MSG_PROCESS_ERROR;
  }
  
  MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt)
  {
      int i;
      MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;
      unsigned long cert_list_len, cert_len;
      X509 *x = NULL;
      const unsigned char *certstart, *certbytes;
      STACK_OF(X509) *sk = NULL;
      EVP_PKEY *pkey = NULL;
      size_t chainidx, certidx;
      unsigned int context = 0;
      const SSL_CERT_LOOKUP *clu;
  
      if ((sk = sk_X509_new_null()) == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                   ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      if ((SSL_IS_TLS13(s) && !PACKET_get_1(pkt, &context))
              || context != 0
              || !PACKET_get_net_3(pkt, &cert_list_len)
              || PACKET_remaining(pkt) != cert_list_len
              || PACKET_remaining(pkt) == 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                   SSL_R_LENGTH_MISMATCH);
          goto err;
      }
      for (chainidx = 0; PACKET_remaining(pkt); chainidx++) {
          if (!PACKET_get_net_3(pkt, &cert_len)
              || !PACKET_get_bytes(pkt, &certbytes, cert_len)) {
              SSLfatal(s, SSL_AD_DECODE_ERROR,
                       SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                       SSL_R_CERT_LENGTH_MISMATCH);
              goto err;
          }
  
          certstart = certbytes;
          x = d2i_X509(NULL, (const unsigned char **)&certbytes, cert_len);
          if (x == NULL) {
              SSLfatal(s, SSL_AD_BAD_CERTIFICATE,
                       SSL_F_TLS_PROCESS_SERVER_CERTIFICATE, ERR_R_ASN1_LIB);
              goto err;
          }
          if (certbytes != (certstart + cert_len)) {
              SSLfatal(s, SSL_AD_DECODE_ERROR,
                       SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                       SSL_R_CERT_LENGTH_MISMATCH);
              goto err;
          }
  
          if (SSL_IS_TLS13(s)) {
              RAW_EXTENSION *rawexts = NULL;
              PACKET extensions;
  
              if (!PACKET_get_length_prefixed_2(pkt, &extensions)) {
                  SSLfatal(s, SSL_AD_DECODE_ERROR,
                           SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                           SSL_R_BAD_LENGTH);
                  goto err;
              }
              if (!tls_collect_extensions(s, &extensions,
                                          SSL_EXT_TLS1_3_CERTIFICATE, &rawexts,
                                          NULL, chainidx == 0)
                  || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE,
                                               rawexts, x, chainidx,
                                               PACKET_remaining(pkt) == 0)) {
                  OPENSSL_free(rawexts);
                  /* SSLfatal already called */
                  goto err;
              }
              OPENSSL_free(rawexts);
          }
  
          if (!sk_X509_push(sk, x)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                       ERR_R_MALLOC_FAILURE);
              goto err;
          }
          x = NULL;
      }
  
      i = ssl_verify_cert_chain(s, sk);
      /*
       * The documented interface is that SSL_VERIFY_PEER should be set in order
       * for client side verification of the server certificate to take place.
       * However, historically the code has only checked that *any* flag is set
       * to cause server verification to take place. Use of the other flags makes
       * no sense in client mode. An attempt to clean up the semantics was
       * reverted because at least one application *only* set
       * SSL_VERIFY_FAIL_IF_NO_PEER_CERT. Prior to the clean up this still caused
       * server verification to take place, after the clean up it silently did
       * nothing. SSL_CTX_set_verify()/SSL_set_verify() cannot validate the flags
       * sent to them because they are void functions. Therefore, we now use the
       * (less clean) historic behaviour of performing validation if any flag is
       * set. The *documented* interface remains the same.
       */
      if (s->verify_mode != SSL_VERIFY_NONE && i <= 0) {
          SSLfatal(s, ssl_x509err2alert(s->verify_result),
                   SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                   SSL_R_CERTIFICATE_VERIFY_FAILED);
          goto err;
      }
      ERR_clear_error();          /* but we keep s->verify_result */
      if (i > 1) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
                   SSL_F_TLS_PROCESS_SERVER_CERTIFICATE, i);
          goto err;
      }
  
      s->session->peer_chain = sk;
      /*
       * Inconsistency alert: cert_chain does include the peer's certificate,
       * which we don't include in statem_srvr.c
       */
      x = sk_X509_value(sk, 0);
      sk = NULL;
  
      pkey = X509_get0_pubkey(x);
  
      if (pkey == NULL || EVP_PKEY_missing_parameters(pkey)) {
          x = NULL;
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                   SSL_R_UNABLE_TO_FIND_PUBLIC_KEY_PARAMETERS);
          goto err;
      }
  
      if ((clu = ssl_cert_lookup_by_pkey(pkey, &certidx)) == NULL) {
          x = NULL;
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                   SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                   SSL_R_UNKNOWN_CERTIFICATE_TYPE);
          goto err;
      }
      /*
       * Check certificate type is consistent with ciphersuite. For TLS 1.3
       * skip check since TLS 1.3 ciphersuites can be used with any certificate
       * type.
       */
      if (!SSL_IS_TLS13(s)) {
          if ((clu->amask & s->s3->tmp.new_cipher->algorithm_auth) == 0) {
              x = NULL;
              SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                       SSL_F_TLS_PROCESS_SERVER_CERTIFICATE,
                       SSL_R_WRONG_CERTIFICATE_TYPE);
              goto err;
          }
      }
  
      X509_free(s->session->peer);
      X509_up_ref(x);
      s->session->peer = x;
      s->session->verify_result = s->verify_result;
      x = NULL;
  
      /* Save the current hash state for when we receive the CertificateVerify */
      if (SSL_IS_TLS13(s)
              && !ssl_handshake_hash(s, s->cert_verify_hash,
                                     sizeof(s->cert_verify_hash),
                                     &s->cert_verify_hash_len)) {
          /* SSLfatal() already called */;
          goto err;
      }
  
      ret = MSG_PROCESS_CONTINUE_READING;
  
   err:
      X509_free(x);
      sk_X509_pop_free(sk, X509_free);
      return ret;
  }
  
  static int tls_process_ske_psk_preamble(SSL *s, PACKET *pkt)
  {
  #ifndef OPENSSL_NO_PSK
      PACKET psk_identity_hint;
  
      /* PSK ciphersuites are preceded by an identity hint */
  
      if (!PACKET_get_length_prefixed_2(pkt, &psk_identity_hint)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SKE_PSK_PREAMBLE,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      /*
       * Store PSK identity hint for later use, hint is used in
       * tls_construct_client_key_exchange.  Assume that the maximum length of
       * a PSK identity hint can be as long as the maximum length of a PSK
       * identity.
       */
      if (PACKET_remaining(&psk_identity_hint) > PSK_MAX_IDENTITY_LEN) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
                   SSL_F_TLS_PROCESS_SKE_PSK_PREAMBLE,
                   SSL_R_DATA_LENGTH_TOO_LONG);
          return 0;
      }
  
      if (PACKET_remaining(&psk_identity_hint) == 0) {
          OPENSSL_free(s->session->psk_identity_hint);
          s->session->psk_identity_hint = NULL;
      } else if (!PACKET_strndup(&psk_identity_hint,
                                 &s->session->psk_identity_hint)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_PSK_PREAMBLE,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      return 1;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_PSK_PREAMBLE,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  static int tls_process_ske_srp(SSL *s, PACKET *pkt, EVP_PKEY **pkey)
  {
  #ifndef OPENSSL_NO_SRP
      PACKET prime, generator, salt, server_pub;
  
      if (!PACKET_get_length_prefixed_2(pkt, &prime)
          || !PACKET_get_length_prefixed_2(pkt, &generator)
          || !PACKET_get_length_prefixed_1(pkt, &salt)
          || !PACKET_get_length_prefixed_2(pkt, &server_pub)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SKE_SRP,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      /* TODO(size_t): Convert BN_bin2bn() calls */
      if ((s->srp_ctx.N =
           BN_bin2bn(PACKET_data(&prime),
                     (int)PACKET_remaining(&prime), NULL)) == NULL
          || (s->srp_ctx.g =
              BN_bin2bn(PACKET_data(&generator),
                        (int)PACKET_remaining(&generator), NULL)) == NULL
          || (s->srp_ctx.s =
              BN_bin2bn(PACKET_data(&salt),
                        (int)PACKET_remaining(&salt), NULL)) == NULL
          || (s->srp_ctx.B =
              BN_bin2bn(PACKET_data(&server_pub),
                        (int)PACKET_remaining(&server_pub), NULL)) == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_SRP,
                   ERR_R_BN_LIB);
          return 0;
      }
  
      if (!srp_verify_server_param(s)) {
          /* SSLfatal() already called */
          return 0;
      }
  
      /* We must check if there is a certificate */
      if (s->s3->tmp.new_cipher->algorithm_auth & (SSL_aRSA | SSL_aDSS))
          *pkey = X509_get0_pubkey(s->session->peer);
  
      return 1;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_SRP,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  static int tls_process_ske_dhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey)
  {
  #ifndef OPENSSL_NO_DH
      PACKET prime, generator, pub_key;
      EVP_PKEY *peer_tmp = NULL;
  
      DH *dh = NULL;
      BIGNUM *p = NULL, *g = NULL, *bnpub_key = NULL;
  
      int check_bits = 0;
  
      if (!PACKET_get_length_prefixed_2(pkt, &prime)
          || !PACKET_get_length_prefixed_2(pkt, &generator)
          || !PACKET_get_length_prefixed_2(pkt, &pub_key)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SKE_DHE,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      peer_tmp = EVP_PKEY_new();
      dh = DH_new();
  
      if (peer_tmp == NULL || dh == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_DHE,
                   ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      /* TODO(size_t): Convert these calls */
      p = BN_bin2bn(PACKET_data(&prime), (int)PACKET_remaining(&prime), NULL);
      g = BN_bin2bn(PACKET_data(&generator), (int)PACKET_remaining(&generator),
                    NULL);
      bnpub_key = BN_bin2bn(PACKET_data(&pub_key),
                            (int)PACKET_remaining(&pub_key), NULL);
      if (p == NULL || g == NULL || bnpub_key == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_DHE,
                   ERR_R_BN_LIB);
          goto err;
      }
  
      /* test non-zero pubkey */
      if (BN_is_zero(bnpub_key)) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SKE_DHE,
                   SSL_R_BAD_DH_VALUE);
          goto err;
      }
  
      if (!DH_set0_pqg(dh, p, NULL, g)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_DHE,
                   ERR_R_BN_LIB);
          goto err;
      }
      p = g = NULL;
  
      if (DH_check_params(dh, &check_bits) == 0 || check_bits != 0) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SKE_DHE,
                   SSL_R_BAD_DH_VALUE);
          goto err;
      }
  
      if (!DH_set0_key(dh, bnpub_key, NULL)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_DHE,
                   ERR_R_BN_LIB);
          goto err;
      }
      bnpub_key = NULL;
  
      if (EVP_PKEY_assign_DH(peer_tmp, dh) == 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_DHE,
                   ERR_R_EVP_LIB);
          goto err;
      }
      dh = NULL;
  
      if (!ssl_security(s, SSL_SECOP_TMP_DH, EVP_PKEY_security_bits(peer_tmp),
                        0, peer_tmp)) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_PROCESS_SKE_DHE,
                   SSL_R_DH_KEY_TOO_SMALL);
          goto err;
      }
  
      s->s3->peer_tmp = peer_tmp;
  
      /*
       * FIXME: This makes assumptions about which ciphersuites come with
       * public keys. We should have a less ad-hoc way of doing this
       */
      if (s->s3->tmp.new_cipher->algorithm_auth & (SSL_aRSA | SSL_aDSS))
          *pkey = X509_get0_pubkey(s->session->peer);
      /* else anonymous DH, so no certificate or pkey. */
  
      return 1;
  
   err:
      BN_free(p);
      BN_free(g);
      BN_free(bnpub_key);
      DH_free(dh);
      EVP_PKEY_free(peer_tmp);
  
      return 0;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_DHE,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  static int tls_process_ske_ecdhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey)
  {
  #ifndef OPENSSL_NO_EC
      PACKET encoded_pt;
      unsigned int curve_type, curve_id;
  
      /*
       * Extract elliptic curve parameters and the server's ephemeral ECDH
       * public key. We only support named (not generic) curves and
       * ECParameters in this case is just three bytes.
       */
      if (!PACKET_get_1(pkt, &curve_type) || !PACKET_get_net_2(pkt, &curve_id)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SKE_ECDHE,
                   SSL_R_LENGTH_TOO_SHORT);
          return 0;
      }
      /*
       * Check curve is named curve type and one of our preferences, if not
       * server has sent an invalid curve.
       */
      if (curve_type != NAMED_CURVE_TYPE
              || !tls1_check_group_id(s, curve_id, 1)) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SKE_ECDHE,
                   SSL_R_WRONG_CURVE);
          return 0;
      }
  
      if ((s->s3->peer_tmp = ssl_generate_param_group(curve_id)) == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_ECDHE,
                   SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS);
          return 0;
      }
  
      if (!PACKET_get_length_prefixed_1(pkt, &encoded_pt)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SKE_ECDHE,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      if (!EVP_PKEY_set1_tls_encodedpoint(s->s3->peer_tmp,
                                          PACKET_data(&encoded_pt),
                                          PACKET_remaining(&encoded_pt))) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_SKE_ECDHE,
                   SSL_R_BAD_ECPOINT);
          return 0;
      }
  
      /*
       * The ECC/TLS specification does not mention the use of DSA to sign
       * ECParameters in the server key exchange message. We do support RSA
       * and ECDSA.
       */
      if (s->s3->tmp.new_cipher->algorithm_auth & SSL_aECDSA)
          *pkey = X509_get0_pubkey(s->session->peer);
      else if (s->s3->tmp.new_cipher->algorithm_auth & SSL_aRSA)
          *pkey = X509_get0_pubkey(s->session->peer);
      /* else anonymous ECDH, so no certificate or pkey. */
  
      return 1;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SKE_ECDHE,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)
  {
      long alg_k;
      EVP_PKEY *pkey = NULL;
      EVP_MD_CTX *md_ctx = NULL;
      EVP_PKEY_CTX *pctx = NULL;
      PACKET save_param_start, signature;
  
      alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
  
      save_param_start = *pkt;
  
  #if !defined(OPENSSL_NO_EC) || !defined(OPENSSL_NO_DH)
      EVP_PKEY_free(s->s3->peer_tmp);
      s->s3->peer_tmp = NULL;
  #endif
  
      if (alg_k & SSL_PSK) {
          if (!tls_process_ske_psk_preamble(s, pkt)) {
              /* SSLfatal() already called */
              goto err;
          }
      }
  
      /* Nothing else to do for plain PSK or RSAPSK */
      if (alg_k & (SSL_kPSK | SSL_kRSAPSK)) {
      } else if (alg_k & SSL_kSRP) {
          if (!tls_process_ske_srp(s, pkt, &pkey)) {
              /* SSLfatal() already called */
              goto err;
          }
      } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
          if (!tls_process_ske_dhe(s, pkt, &pkey)) {
              /* SSLfatal() already called */
              goto err;
          }
      } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
          if (!tls_process_ske_ecdhe(s, pkt, &pkey)) {
              /* SSLfatal() already called */
              goto err;
          }
      } else if (alg_k) {
          SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                   SSL_R_UNEXPECTED_MESSAGE);
          goto err;
      }
  
      /* if it was signed, check the signature */
      if (pkey != NULL) {
          PACKET params;
          int maxsig;
          const EVP_MD *md = NULL;
          unsigned char *tbs;
          size_t tbslen;
          int rv;
  
          /*
           * |pkt| now points to the beginning of the signature, so the difference
           * equals the length of the parameters.
           */
          if (!PACKET_get_sub_packet(&save_param_start, &params,
                                     PACKET_remaining(&save_param_start) -
                                     PACKET_remaining(pkt))) {
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       ERR_R_INTERNAL_ERROR);
              goto err;
          }
  
          if (SSL_USE_SIGALGS(s)) {
              unsigned int sigalg;
  
              if (!PACKET_get_net_2(pkt, &sigalg)) {
                  SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                           SSL_R_LENGTH_TOO_SHORT);
                  goto err;
              }
              if (tls12_check_peer_sigalg(s, sigalg, pkey) <=0) {
                  /* SSLfatal() already called */
                  goto err;
              }
          } else if (!tls1_set_peer_legacy_sigalg(s, pkey)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       ERR_R_INTERNAL_ERROR);
              goto err;
          }
  
          if (!tls1_lookup_md(s->s3->tmp.peer_sigalg, &md)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       ERR_R_INTERNAL_ERROR);
              goto err;
          }
  #ifdef SSL_DEBUG
          if (SSL_USE_SIGALGS(s))
              fprintf(stderr, "USING TLSv1.2 HASH %s\n",
                      md == NULL ? "n/a" : EVP_MD_name(md));
  #endif
  
          if (!PACKET_get_length_prefixed_2(pkt, &signature)
              || PACKET_remaining(pkt) != 0) {
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       SSL_R_LENGTH_MISMATCH);
              goto err;
          }
          maxsig = EVP_PKEY_size(pkey);
          if (maxsig < 0) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       ERR_R_INTERNAL_ERROR);
              goto err;
          }
  
          /*
           * Check signature length
           */
          if (PACKET_remaining(&signature) > (size_t)maxsig) {
              /* wrong packet length */
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                     SSL_R_WRONG_SIGNATURE_LENGTH);
              goto err;
          }
  
          md_ctx = EVP_MD_CTX_new();
          if (md_ctx == NULL) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       ERR_R_MALLOC_FAILURE);
              goto err;
          }
  
          if (EVP_DigestVerifyInit(md_ctx, &pctx, md, NULL, pkey) <= 0) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       ERR_R_EVP_LIB);
              goto err;
          }
          if (SSL_USE_PSS(s)) {
              if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
                  || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx,
                                                  RSA_PSS_SALTLEN_DIGEST) <= 0) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_EVP_LIB);
                  goto err;
              }
          }
          tbslen = construct_key_exchange_tbs(s, &tbs, PACKET_data(&params),
                                              PACKET_remaining(&params));
          if (tbslen == 0) {
              /* SSLfatal() already called */
              goto err;
          }
  
          rv = EVP_DigestVerify(md_ctx, PACKET_data(&signature),
                                PACKET_remaining(&signature), tbs, tbslen);
          OPENSSL_free(tbs);
          if (rv <= 0) {
              SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       SSL_R_BAD_SIGNATURE);
              goto err;
          }
          EVP_MD_CTX_free(md_ctx);
          md_ctx = NULL;
      } else {
          /* aNULL, aSRP or PSK do not need public keys */
          if (!(s->s3->tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP))
              && !(alg_k & SSL_PSK)) {
              /* Might be wrong key type, check it */
              if (ssl3_check_cert_and_algorithm(s)) {
                  SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                           SSL_R_BAD_DATA);
              }
              /* else this shouldn't happen, SSLfatal() already called */
              goto err;
          }
          /* still data left over */
          if (PACKET_remaining(pkt) != 0) {
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_KEY_EXCHANGE,
                       SSL_R_EXTRA_DATA_IN_MESSAGE);
              goto err;
          }
      }
  
      return MSG_PROCESS_CONTINUE_READING;
   err:
      EVP_MD_CTX_free(md_ctx);
      return MSG_PROCESS_ERROR;
  }
  
  MSG_PROCESS_RETURN tls_process_certificate_request(SSL *s, PACKET *pkt)
  {
      size_t i;
  
      /* Clear certificate validity flags */
      for (i = 0; i < SSL_PKEY_NUM; i++)
          s->s3->tmp.valid_flags[i] = 0;
  
      if (SSL_IS_TLS13(s)) {
          PACKET reqctx, extensions;
          RAW_EXTENSION *rawexts = NULL;
  
          if ((s->shutdown & SSL_SENT_SHUTDOWN) != 0) {
              /*
               * We already sent close_notify. This can only happen in TLSv1.3
               * post-handshake messages. We can't reasonably respond to this, so
               * we just ignore it
               */
              return MSG_PROCESS_FINISHED_READING;
          }
  
          /* Free and zero certificate types: it is not present in TLS 1.3 */
          OPENSSL_free(s->s3->tmp.ctype);
          s->s3->tmp.ctype = NULL;
          s->s3->tmp.ctype_len = 0;
          OPENSSL_free(s->pha_context);
          s->pha_context = NULL;
          s->pha_context_len = 0;
  
          if (!PACKET_get_length_prefixed_1(pkt, &reqctx) ||
              !PACKET_memdup(&reqctx, &s->pha_context, &s->pha_context_len)) {
              SSLfatal(s, SSL_AD_DECODE_ERROR,
                       SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                       SSL_R_LENGTH_MISMATCH);
              return MSG_PROCESS_ERROR;
          }
  
          if (!PACKET_get_length_prefixed_2(pkt, &extensions)) {
              SSLfatal(s, SSL_AD_DECODE_ERROR,
                       SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                       SSL_R_BAD_LENGTH);
              return MSG_PROCESS_ERROR;
          }
          if (!tls_collect_extensions(s, &extensions,
                                      SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
                                      &rawexts, NULL, 1)
              || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
                                           rawexts, NULL, 0, 1)) {
              /* SSLfatal() already called */
              OPENSSL_free(rawexts);
              return MSG_PROCESS_ERROR;
          }
          OPENSSL_free(rawexts);
          if (!tls1_process_sigalgs(s)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                       SSL_R_BAD_LENGTH);
              return MSG_PROCESS_ERROR;
          }
      } else {
          PACKET ctypes;
  
          /* get the certificate types */
          if (!PACKET_get_length_prefixed_1(pkt, &ctypes)) {
              SSLfatal(s, SSL_AD_DECODE_ERROR,
                       SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                       SSL_R_LENGTH_MISMATCH);
              return MSG_PROCESS_ERROR;
          }
  
          if (!PACKET_memdup(&ctypes, &s->s3->tmp.ctype, &s->s3->tmp.ctype_len)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                       ERR_R_INTERNAL_ERROR);
              return MSG_PROCESS_ERROR;
          }
  
          if (SSL_USE_SIGALGS(s)) {
              PACKET sigalgs;
  
              if (!PACKET_get_length_prefixed_2(pkt, &sigalgs)) {
                  SSLfatal(s, SSL_AD_DECODE_ERROR,
                           SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                           SSL_R_LENGTH_MISMATCH);
                  return MSG_PROCESS_ERROR;
              }
  
              /*
               * Despite this being for certificates, preserve compatibility
               * with pre-TLS 1.3 and use the regular sigalgs field.
               */
              if (!tls1_save_sigalgs(s, &sigalgs, 0)) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                           SSL_R_SIGNATURE_ALGORITHMS_ERROR);
                  return MSG_PROCESS_ERROR;
              }
              if (!tls1_process_sigalgs(s)) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                           ERR_R_MALLOC_FAILURE);
                  return MSG_PROCESS_ERROR;
              }
          }
  
          /* get the CA RDNs */
          if (!parse_ca_names(s, pkt)) {
              /* SSLfatal() already called */
              return MSG_PROCESS_ERROR;
          }
      }
  
      if (PACKET_remaining(pkt) != 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR,
                   SSL_F_TLS_PROCESS_CERTIFICATE_REQUEST,
                   SSL_R_LENGTH_MISMATCH);
          return MSG_PROCESS_ERROR;
      }
  
      /* we should setup a certificate to return.... */
      s->s3->tmp.cert_req = 1;
  
      /*
       * In TLSv1.3 we don't prepare the client certificate yet. We wait until
       * after the CertificateVerify message has been received. This is because
       * in TLSv1.3 the CertificateRequest arrives before the Certificate message
       * but in TLSv1.2 it is the other way around. We want to make sure that
       * SSL_get_peer_certificate() returns something sensible in
       * client_cert_cb.
       */
      if (SSL_IS_TLS13(s) && s->post_handshake_auth != SSL_PHA_REQUESTED)
          return MSG_PROCESS_CONTINUE_READING;
  
      return MSG_PROCESS_CONTINUE_PROCESSING;
  }
  
  MSG_PROCESS_RETURN tls_process_new_session_ticket(SSL *s, PACKET *pkt)
  {
      unsigned int ticklen;
      unsigned long ticket_lifetime_hint, age_add = 0;
      unsigned int sess_len;
      RAW_EXTENSION *exts = NULL;
      PACKET nonce;
  
      PACKET_null_init(&nonce);
  
      if (!PACKET_get_net_4(pkt, &ticket_lifetime_hint)
          || (SSL_IS_TLS13(s)
              && (!PACKET_get_net_4(pkt, &age_add)
                  || !PACKET_get_length_prefixed_1(pkt, &nonce)))
          || !PACKET_get_net_2(pkt, &ticklen)
          || (SSL_IS_TLS13(s) ? (ticklen == 0 || PACKET_remaining(pkt) < ticklen)
                              : PACKET_remaining(pkt) != ticklen)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_NEW_SESSION_TICKET,
                   SSL_R_LENGTH_MISMATCH);
          goto err;
      }
  
      /*
       * Server is allowed to change its mind (in <=TLSv1.2) and send an empty
       * ticket. We already checked this TLSv1.3 case above, so it should never
       * be 0 here in that instance
       */
      if (ticklen == 0)
          return MSG_PROCESS_CONTINUE_READING;
  
      /*
       * Sessions must be immutable once they go into the session cache. Otherwise
       * we can get multi-thread problems. Therefore we don't "update" sessions,
       * we replace them with a duplicate. In TLSv1.3 we need to do this every
       * time a NewSessionTicket arrives because those messages arrive
       * post-handshake and the session may have already gone into the session
       * cache.
       */
      if (SSL_IS_TLS13(s) || s->session->session_id_length > 0) {
          SSL_SESSION *new_sess;
  
          /*
           * We reused an existing session, so we need to replace it with a new
           * one
           */
          if ((new_sess = ssl_session_dup(s->session, 0)) == 0) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_PROCESS_NEW_SESSION_TICKET,
                       ERR_R_MALLOC_FAILURE);
              goto err;
          }
  
          if ((s->session_ctx->session_cache_mode & SSL_SESS_CACHE_CLIENT) != 0
                  && !SSL_IS_TLS13(s)) {
              /*
               * In TLSv1.2 and below the arrival of a new tickets signals that
               * any old ticket we were using is now out of date, so we remove the
               * old session from the cache. We carry on if this fails
               */
              SSL_CTX_remove_session(s->session_ctx, s->session);
          }
  
          SSL_SESSION_free(s->session);
          s->session = new_sess;
      }
  
      /*
       * Technically the cast to long here is not guaranteed by the C standard -
       * but we use it elsewhere, so this should be ok.
       */
      s->session->time = (long)time(NULL);
  
      OPENSSL_free(s->session->ext.tick);
      s->session->ext.tick = NULL;
      s->session->ext.ticklen = 0;
  
      s->session->ext.tick = OPENSSL_malloc(ticklen);
      if (s->session->ext.tick == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_NEW_SESSION_TICKET,
                   ERR_R_MALLOC_FAILURE);
          goto err;
      }
      if (!PACKET_copy_bytes(pkt, s->session->ext.tick, ticklen)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_NEW_SESSION_TICKET,
                   SSL_R_LENGTH_MISMATCH);
          goto err;
      }
  
      s->session->ext.tick_lifetime_hint = ticket_lifetime_hint;
      s->session->ext.tick_age_add = age_add;
      s->session->ext.ticklen = ticklen;
  
      if (SSL_IS_TLS13(s)) {
          PACKET extpkt;
  
          if (!PACKET_as_length_prefixed_2(pkt, &extpkt)
                  || PACKET_remaining(pkt) != 0) {
              SSLfatal(s, SSL_AD_DECODE_ERROR,
                       SSL_F_TLS_PROCESS_NEW_SESSION_TICKET,
                       SSL_R_LENGTH_MISMATCH);
              goto err;
          }
  
          if (!tls_collect_extensions(s, &extpkt,
                                      SSL_EXT_TLS1_3_NEW_SESSION_TICKET, &exts,
                                      NULL, 1)
                  || !tls_parse_all_extensions(s,
                                               SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
                                               exts, NULL, 0, 1)) {
              /* SSLfatal() already called */
              goto err;
          }
      }
  
      /*
       * There are two ways to detect a resumed ticket session. One is to set
       * an appropriate session ID and then the server must return a match in
       * ServerHello. This allows the normal client session ID matching to work
       * and we know much earlier that the ticket has been accepted. The
       * other way is to set zero length session ID when the ticket is
       * presented and rely on the handshake to determine session resumption.
       * We choose the former approach because this fits in with assumptions
       * elsewhere in OpenSSL. The session ID is set to the SHA256 (or SHA1 is
       * SHA256 is disabled) hash of the ticket.
       */
      /*
       * TODO(size_t): we use sess_len here because EVP_Digest expects an int
       * but s->session->session_id_length is a size_t
       */
      if (!EVP_Digest(s->session->ext.tick, ticklen,
                      s->session->session_id, &sess_len,
                      EVP_sha256(), NULL)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_NEW_SESSION_TICKET,
                   ERR_R_EVP_LIB);
          goto err;
      }
      s->session->session_id_length = sess_len;
      s->session->not_resumable = 0;
  
      /* This is a standalone message in TLSv1.3, so there is no more to read */
      if (SSL_IS_TLS13(s)) {
          const EVP_MD *md = ssl_handshake_md(s);
          int hashleni = EVP_MD_size(md);
          size_t hashlen;
          static const unsigned char nonce_label[] = "resumption";
  
          /* Ensure cast to size_t is safe */
          if (!ossl_assert(hashleni >= 0)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_PROCESS_NEW_SESSION_TICKET,
                       ERR_R_INTERNAL_ERROR);
              goto err;
          }
          hashlen = (size_t)hashleni;
  
          if (!tls13_hkdf_expand(s, md, s->resumption_master_secret,
                                 nonce_label,
                                 sizeof(nonce_label) - 1,
                                 PACKET_data(&nonce),
                                 PACKET_remaining(&nonce),
                                 s->session->master_key,
                                 hashlen, 1)) {
              /* SSLfatal() already called */
              goto err;
          }
          s->session->master_key_length = hashlen;
  
          OPENSSL_free(exts);
          ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
          return MSG_PROCESS_FINISHED_READING;
      }
  
      return MSG_PROCESS_CONTINUE_READING;
   err:
      OPENSSL_free(exts);
      return MSG_PROCESS_ERROR;
  }
  
  /*
   * In TLSv1.3 this is called from the extensions code, otherwise it is used to
   * parse a separate message. Returns 1 on success or 0 on failure
   */
  int tls_process_cert_status_body(SSL *s, PACKET *pkt)
  {
      size_t resplen;
      unsigned int type;
  
      if (!PACKET_get_1(pkt, &type)
          || type != TLSEXT_STATUSTYPE_ocsp) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CERT_STATUS_BODY,
                   SSL_R_UNSUPPORTED_STATUS_TYPE);
          return 0;
      }
      if (!PACKET_get_net_3_len(pkt, &resplen)
          || PACKET_remaining(pkt) != resplen) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CERT_STATUS_BODY,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
      s->ext.ocsp.resp = OPENSSL_malloc(resplen);
      if (s->ext.ocsp.resp == NULL) {
          s->ext.ocsp.resp_len = 0;
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CERT_STATUS_BODY,
                   ERR_R_MALLOC_FAILURE);
          return 0;
      }
      s->ext.ocsp.resp_len = resplen;
      if (!PACKET_copy_bytes(pkt, s->ext.ocsp.resp, resplen)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CERT_STATUS_BODY,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      return 1;
  }
  
  
  MSG_PROCESS_RETURN tls_process_cert_status(SSL *s, PACKET *pkt)
  {
      if (!tls_process_cert_status_body(s, pkt)) {
          /* SSLfatal() already called */
          return MSG_PROCESS_ERROR;
      }
  
      return MSG_PROCESS_CONTINUE_READING;
  }
  
  /*
   * Perform miscellaneous checks and processing after we have received the
   * server's initial flight. In TLS1.3 this is after the Server Finished message.
   * In <=TLS1.2 this is after the ServerDone message. Returns 1 on success or 0
   * on failure.
   */
  int tls_process_initial_server_flight(SSL *s)
  {
      /*
       * at this point we check that we have the required stuff from
       * the server
       */
      if (!ssl3_check_cert_and_algorithm(s)) {
          /* SSLfatal() already called */
          return 0;
      }
  
      /*
       * Call the ocsp status callback if needed. The |ext.ocsp.resp| and
       * |ext.ocsp.resp_len| values will be set if we actually received a status
       * message, or NULL and -1 otherwise
       */
      if (s->ext.status_type != TLSEXT_STATUSTYPE_nothing
              && s->ctx->ext.status_cb != NULL) {
          int ret = s->ctx->ext.status_cb(s, s->ctx->ext.status_arg);
  
          if (ret == 0) {
              SSLfatal(s, SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE,
                       SSL_F_TLS_PROCESS_INITIAL_SERVER_FLIGHT,
                       SSL_R_INVALID_STATUS_RESPONSE);
              return 0;
          }
          if (ret < 0) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_PROCESS_INITIAL_SERVER_FLIGHT,
                       SSL_R_OCSP_CALLBACK_FAILURE);
              return 0;
          }
      }
  #ifndef OPENSSL_NO_CT
      if (s->ct_validation_callback != NULL) {
          /* Note we validate the SCTs whether or not we abort on error */
          if (!ssl_validate_ct(s) && (s->verify_mode & SSL_VERIFY_PEER)) {
              /* SSLfatal() already called */
              return 0;
          }
      }
  #endif
  
      return 1;
  }
  
  MSG_PROCESS_RETURN tls_process_server_done(SSL *s, PACKET *pkt)
  {
      if (PACKET_remaining(pkt) > 0) {
          /* should contain no data */
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_SERVER_DONE,
                   SSL_R_LENGTH_MISMATCH);
          return MSG_PROCESS_ERROR;
      }
  #ifndef OPENSSL_NO_SRP
      if (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kSRP) {
          if (SRP_Calc_A_param(s) <= 0) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_SERVER_DONE,
                       SSL_R_SRP_A_CALC);
              return MSG_PROCESS_ERROR;
          }
      }
  #endif
  
      if (!tls_process_initial_server_flight(s)) {
          /* SSLfatal() already called */
          return MSG_PROCESS_ERROR;
      }
  
      return MSG_PROCESS_FINISHED_READING;
  }
  
  static int tls_construct_cke_psk_preamble(SSL *s, WPACKET *pkt)
  {
  #ifndef OPENSSL_NO_PSK
      int ret = 0;
      /*
       * The callback needs PSK_MAX_IDENTITY_LEN + 1 bytes to return a
       * \0-terminated identity. The last byte is for us for simulating
       * strnlen.
       */
      char identity[PSK_MAX_IDENTITY_LEN + 1];
      size_t identitylen = 0;
      unsigned char psk[PSK_MAX_PSK_LEN];
      unsigned char *tmppsk = NULL;
      char *tmpidentity = NULL;
      size_t psklen = 0;
  
      if (s->psk_client_callback == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_PSK_PREAMBLE,
                   SSL_R_PSK_NO_CLIENT_CB);
          goto err;
      }
  
      memset(identity, 0, sizeof(identity));
  
      psklen = s->psk_client_callback(s, s->session->psk_identity_hint,
                                      identity, sizeof(identity) - 1,
                                      psk, sizeof(psk));
  
      if (psklen > PSK_MAX_PSK_LEN) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
                   SSL_F_TLS_CONSTRUCT_CKE_PSK_PREAMBLE, ERR_R_INTERNAL_ERROR);
          psklen = PSK_MAX_PSK_LEN;   /* Avoid overrunning the array on cleanse */
          goto err;
      } else if (psklen == 0) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
                   SSL_F_TLS_CONSTRUCT_CKE_PSK_PREAMBLE,
                   SSL_R_PSK_IDENTITY_NOT_FOUND);
          goto err;
      }
  
      identitylen = strlen(identity);
      if (identitylen > PSK_MAX_IDENTITY_LEN) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_PSK_PREAMBLE,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      tmppsk = OPENSSL_memdup(psk, psklen);
      tmpidentity = OPENSSL_strdup(identity);
      if (tmppsk == NULL || tmpidentity == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_PSK_PREAMBLE,
                   ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      OPENSSL_free(s->s3->tmp.psk);
      s->s3->tmp.psk = tmppsk;
      s->s3->tmp.psklen = psklen;
      tmppsk = NULL;
      OPENSSL_free(s->session->psk_identity);
      s->session->psk_identity = tmpidentity;
      tmpidentity = NULL;
  
      if (!WPACKET_sub_memcpy_u16(pkt, identity, identitylen))  {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_PSK_PREAMBLE,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      ret = 1;
  
   err:
      OPENSSL_cleanse(psk, psklen);
      OPENSSL_cleanse(identity, sizeof(identity));
      OPENSSL_clear_free(tmppsk, psklen);
      OPENSSL_clear_free(tmpidentity, identitylen);
  
      return ret;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_PSK_PREAMBLE,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  static int tls_construct_cke_rsa(SSL *s, WPACKET *pkt)
  {
  #ifndef OPENSSL_NO_RSA
      unsigned char *encdata = NULL;
      EVP_PKEY *pkey = NULL;
      EVP_PKEY_CTX *pctx = NULL;
      size_t enclen;
      unsigned char *pms = NULL;
      size_t pmslen = 0;
  
      if (s->session->peer == NULL) {
          /*
           * We should always have a server certificate with SSL_kRSA.
           */
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      pkey = X509_get0_pubkey(s->session->peer);
      if (EVP_PKEY_get0_RSA(pkey) == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      pmslen = SSL_MAX_MASTER_KEY_LENGTH;
      pms = OPENSSL_malloc(pmslen);
      if (pms == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
                   ERR_R_MALLOC_FAILURE);
          return 0;
      }
  
      pms[0] = s->client_version >> 8;
      pms[1] = s->client_version & 0xff;
      /* TODO(size_t): Convert this function */
      if (RAND_bytes(pms + 2, (int)(pmslen - 2)) <= 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
                   ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      /* Fix buf for TLS and beyond */
      if (s->version > SSL3_VERSION && !WPACKET_start_sub_packet_u16(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
      pctx = EVP_PKEY_CTX_new(pkey, NULL);
      if (pctx == NULL || EVP_PKEY_encrypt_init(pctx) <= 0
          || EVP_PKEY_encrypt(pctx, NULL, &enclen, pms, pmslen) <= 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
                   ERR_R_EVP_LIB);
          goto err;
      }
      if (!WPACKET_allocate_bytes(pkt, enclen, &encdata)
              || EVP_PKEY_encrypt(pctx, encdata, &enclen, pms, pmslen) <= 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
                   SSL_R_BAD_RSA_ENCRYPT);
          goto err;
      }
      EVP_PKEY_CTX_free(pctx);
      pctx = NULL;
  
      /* Fix buf for TLS and beyond */
      if (s->version > SSL3_VERSION && !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      /* Log the premaster secret, if logging is enabled. */
      if (!ssl_log_rsa_client_key_exchange(s, encdata, enclen, pms, pmslen)) {
          /* SSLfatal() already called */
          goto err;
      }
  
      s->s3->tmp.pms = pms;
      s->s3->tmp.pmslen = pmslen;
  
      return 1;
   err:
      OPENSSL_clear_free(pms, pmslen);
      EVP_PKEY_CTX_free(pctx);
  
      return 0;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_RSA,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  static int tls_construct_cke_dhe(SSL *s, WPACKET *pkt)
  {
  #ifndef OPENSSL_NO_DH
      DH *dh_clnt = NULL;
      const BIGNUM *pub_key;
      EVP_PKEY *ckey = NULL, *skey = NULL;
      unsigned char *keybytes = NULL;
  
      skey = s->s3->peer_tmp;
      if (skey == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_DHE,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      ckey = ssl_generate_pkey(skey);
      if (ckey == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_DHE,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      dh_clnt = EVP_PKEY_get0_DH(ckey);
  
      if (dh_clnt == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_DHE,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      if (ssl_derive(s, ckey, skey, 0) == 0) {
          /* SSLfatal() already called */
          goto err;
      }
  
      /* send off the data */
      DH_get0_key(dh_clnt, &pub_key, NULL);
      if (!WPACKET_sub_allocate_bytes_u16(pkt, BN_num_bytes(pub_key),
                                          &keybytes)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_DHE,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      BN_bn2bin(pub_key, keybytes);
      EVP_PKEY_free(ckey);
  
      return 1;
   err:
      EVP_PKEY_free(ckey);
      return 0;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_DHE,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  static int tls_construct_cke_ecdhe(SSL *s, WPACKET *pkt)
  {
  #ifndef OPENSSL_NO_EC
      unsigned char *encodedPoint = NULL;
      size_t encoded_pt_len = 0;
      EVP_PKEY *ckey = NULL, *skey = NULL;
      int ret = 0;
  
      skey = s->s3->peer_tmp;
      if (skey == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_ECDHE,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      ckey = ssl_generate_pkey(skey);
      if (ckey == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_ECDHE,
                   ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      if (ssl_derive(s, ckey, skey, 0) == 0) {
          /* SSLfatal() already called */
          goto err;
      }
  
      /* Generate encoding of client key */
      encoded_pt_len = EVP_PKEY_get1_tls_encodedpoint(ckey, &encodedPoint);
  
      if (encoded_pt_len == 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_ECDHE,
                   ERR_R_EC_LIB);
          goto err;
      }
  
      if (!WPACKET_sub_memcpy_u8(pkt, encodedPoint, encoded_pt_len)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_ECDHE,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      ret = 1;
   err:
      OPENSSL_free(encodedPoint);
      EVP_PKEY_free(ckey);
      return ret;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_ECDHE,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  static int tls_construct_cke_gost(SSL *s, WPACKET *pkt)
  {
  #ifndef OPENSSL_NO_GOST
      /* GOST key exchange message creation */
      EVP_PKEY_CTX *pkey_ctx = NULL;
      X509 *peer_cert;
      size_t msglen;
      unsigned int md_len;
      unsigned char shared_ukm[32], tmp[256];
      EVP_MD_CTX *ukm_hash = NULL;
      int dgst_nid = NID_id_GostR3411_94;
      unsigned char *pms = NULL;
      size_t pmslen = 0;
  
      if ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aGOST12) != 0)
          dgst_nid = NID_id_GostR3411_2012_256;
  
      /*
       * Get server certificate PKEY and create ctx from it
       */
      peer_cert = s->session->peer;
      if (!peer_cert) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_CONSTRUCT_CKE_GOST,
                 SSL_R_NO_GOST_CERTIFICATE_SENT_BY_PEER);
          return 0;
      }
  
      pkey_ctx = EVP_PKEY_CTX_new(X509_get0_pubkey(peer_cert), NULL);
      if (pkey_ctx == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_GOST,
                   ERR_R_MALLOC_FAILURE);
          return 0;
      }
      /*
       * If we have send a certificate, and certificate key
       * parameters match those of server certificate, use
       * certificate key for key exchange
       */
  
      /* Otherwise, generate ephemeral key pair */
      pmslen = 32;
      pms = OPENSSL_malloc(pmslen);
      if (pms == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_GOST,
                   ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      if (EVP_PKEY_encrypt_init(pkey_ctx) <= 0
          /* Generate session key
           * TODO(size_t): Convert this function
           */
          || RAND_bytes(pms, (int)pmslen) <= 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_GOST,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      };
      /*
       * Compute shared IV and store it in algorithm-specific context
       * data
       */
      ukm_hash = EVP_MD_CTX_new();
      if (ukm_hash == NULL
          || EVP_DigestInit(ukm_hash, EVP_get_digestbynid(dgst_nid)) <= 0
          || EVP_DigestUpdate(ukm_hash, s->s3->client_random,
                              SSL3_RANDOM_SIZE) <= 0
          || EVP_DigestUpdate(ukm_hash, s->s3->server_random,
                              SSL3_RANDOM_SIZE) <= 0
          || EVP_DigestFinal_ex(ukm_hash, shared_ukm, &md_len) <= 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_GOST,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
      EVP_MD_CTX_free(ukm_hash);
      ukm_hash = NULL;
      if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
                            EVP_PKEY_CTRL_SET_IV, 8, shared_ukm) < 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_GOST,
                   SSL_R_LIBRARY_BUG);
          goto err;
      }
      /* Make GOST keytransport blob message */
      /*
       * Encapsulate it into sequence
       */
      msglen = 255;
      if (EVP_PKEY_encrypt(pkey_ctx, tmp, &msglen, pms, pmslen) <= 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_GOST,
                   SSL_R_LIBRARY_BUG);
          goto err;
      }
  
      if (!WPACKET_put_bytes_u8(pkt, V_ASN1_SEQUENCE | V_ASN1_CONSTRUCTED)
              || (msglen >= 0x80 && !WPACKET_put_bytes_u8(pkt, 0x81))
              || !WPACKET_sub_memcpy_u8(pkt, tmp, msglen)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_GOST,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      EVP_PKEY_CTX_free(pkey_ctx);
      s->s3->tmp.pms = pms;
      s->s3->tmp.pmslen = pmslen;
  
      return 1;
   err:
      EVP_PKEY_CTX_free(pkey_ctx);
      OPENSSL_clear_free(pms, pmslen);
      EVP_MD_CTX_free(ukm_hash);
      return 0;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_GOST,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  static int tls_construct_cke_srp(SSL *s, WPACKET *pkt)
  {
  #ifndef OPENSSL_NO_SRP
      unsigned char *abytes = NULL;
  
      if (s->srp_ctx.A == NULL
              || !WPACKET_sub_allocate_bytes_u16(pkt, BN_num_bytes(s->srp_ctx.A),
                                                 &abytes)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_SRP,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
      BN_bn2bin(s->srp_ctx.A, abytes);
  
      OPENSSL_free(s->session->srp_username);
      s->session->srp_username = OPENSSL_strdup(s->srp_ctx.login);
      if (s->session->srp_username == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_SRP,
                   ERR_R_MALLOC_FAILURE);
          return 0;
      }
  
      return 1;
  #else
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CKE_SRP,
               ERR_R_INTERNAL_ERROR);
      return 0;
  #endif
  }
  
  int tls_construct_client_key_exchange(SSL *s, WPACKET *pkt)
  {
      unsigned long alg_k;
  
      alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
  
      /*
       * All of the construct functions below call SSLfatal() if necessary so
       * no need to do so here.
       */
      if ((alg_k & SSL_PSK)
          && !tls_construct_cke_psk_preamble(s, pkt))
          goto err;
  
      if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) {
          if (!tls_construct_cke_rsa(s, pkt))
              goto err;
      } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
          if (!tls_construct_cke_dhe(s, pkt))
              goto err;
      } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
          if (!tls_construct_cke_ecdhe(s, pkt))
              goto err;
      } else if (alg_k & SSL_kGOST) {
          if (!tls_construct_cke_gost(s, pkt))
              goto err;
      } else if (alg_k & SSL_kSRP) {
          if (!tls_construct_cke_srp(s, pkt))
              goto err;
      } else if (!(alg_k & SSL_kPSK)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CLIENT_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      return 1;
   err:
      OPENSSL_clear_free(s->s3->tmp.pms, s->s3->tmp.pmslen);
      s->s3->tmp.pms = NULL;
      s->s3->tmp.pmslen = 0;
  #ifndef OPENSSL_NO_PSK
      OPENSSL_clear_free(s->s3->tmp.psk, s->s3->tmp.psklen);
      s->s3->tmp.psk = NULL;
      s->s3->tmp.psklen = 0;
  #endif
      return 0;
  }
  
  int tls_client_key_exchange_post_work(SSL *s)
  {
      unsigned char *pms = NULL;
      size_t pmslen = 0;
  
      pms = s->s3->tmp.pms;
      pmslen = s->s3->tmp.pmslen;
  
  #ifndef OPENSSL_NO_SRP
      /* Check for SRP */
      if (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kSRP) {
          if (!srp_generate_client_master_secret(s)) {
              /* SSLfatal() already called */
              goto err;
          }
          return 1;
      }
  #endif
  
      if (pms == NULL && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CLIENT_KEY_EXCHANGE_POST_WORK, ERR_R_MALLOC_FAILURE);
          goto err;
      }
      if (!ssl_generate_master_secret(s, pms, pmslen, 1)) {
          /* SSLfatal() already called */
          /* ssl_generate_master_secret frees the pms even on error */
          pms = NULL;
          pmslen = 0;
          goto err;
      }
      pms = NULL;
      pmslen = 0;
  
  #ifndef OPENSSL_NO_SCTP
      if (SSL_IS_DTLS(s)) {
          unsigned char sctpauthkey[64];
          char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
          size_t labellen;
  
          /*
           * Add new shared key for SCTP-Auth, will be ignored if no SCTP
           * used.
           */
          memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
                 sizeof(DTLS1_SCTP_AUTH_LABEL));
  
          /* Don't include the terminating zero. */
          labellen = sizeof(labelbuffer) - 1;
          if (s->mode & SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG)
              labellen += 1;
  
          if (SSL_export_keying_material(s, sctpauthkey,
                                         sizeof(sctpauthkey), labelbuffer,
                                         labellen, NULL, 0, 0) <= 0) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CLIENT_KEY_EXCHANGE_POST_WORK,
                       ERR_R_INTERNAL_ERROR);
              goto err;
          }
  
          BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
                   sizeof(sctpauthkey), sctpauthkey);
      }
  #endif
  
      return 1;
   err:
      OPENSSL_clear_free(pms, pmslen);
      s->s3->tmp.pms = NULL;
      s->s3->tmp.pmslen = 0;
      return 0;
  }
  
  /*
   * Check a certificate can be used for client authentication. Currently check
   * cert exists, if we have a suitable digest for TLS 1.2 if static DH client
   * certificates can be used and optionally checks suitability for Suite B.
   */
  static int ssl3_check_client_certificate(SSL *s)
  {
      /* If no suitable signature algorithm can't use certificate */
      if (!tls_choose_sigalg(s, 0) || s->s3->tmp.sigalg == NULL)
          return 0;
      /*
       * If strict mode check suitability of chain before using it. This also
       * adjusts suite B digest if necessary.
       */
      if (s->cert->cert_flags & SSL_CERT_FLAGS_CHECK_TLS_STRICT &&
          !tls1_check_chain(s, NULL, NULL, NULL, -2))
          return 0;
      return 1;
  }
  
  WORK_STATE tls_prepare_client_certificate(SSL *s, WORK_STATE wst)
  {
      X509 *x509 = NULL;
      EVP_PKEY *pkey = NULL;
      int i;
  
      if (wst == WORK_MORE_A) {
          /* Let cert callback update client certificates if required */
          if (s->cert->cert_cb) {
              i = s->cert->cert_cb(s, s->cert->cert_cb_arg);
              if (i < 0) {
                  s->rwstate = SSL_X509_LOOKUP;
                  return WORK_MORE_A;
              }
              if (i == 0) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_PREPARE_CLIENT_CERTIFICATE,
                           SSL_R_CALLBACK_FAILED);
                  return WORK_ERROR;
              }
              s->rwstate = SSL_NOTHING;
          }
          if (ssl3_check_client_certificate(s)) {
              if (s->post_handshake_auth == SSL_PHA_REQUESTED) {
                  return WORK_FINISHED_STOP;
              }
              return WORK_FINISHED_CONTINUE;
          }
  
          /* Fall through to WORK_MORE_B */
          wst = WORK_MORE_B;
      }
  
      /* We need to get a client cert */
      if (wst == WORK_MORE_B) {
          /*
           * If we get an error, we need to ssl->rwstate=SSL_X509_LOOKUP;
           * return(-1); We then get retied later
           */
          i = ssl_do_client_cert_cb(s, &x509, &pkey);
          if (i < 0) {
              s->rwstate = SSL_X509_LOOKUP;
              return WORK_MORE_B;
          }
          s->rwstate = SSL_NOTHING;
          if ((i == 1) && (pkey != NULL) && (x509 != NULL)) {
              if (!SSL_use_certificate(s, x509) || !SSL_use_PrivateKey(s, pkey))
                  i = 0;
          } else if (i == 1) {
              i = 0;
              SSLerr(SSL_F_TLS_PREPARE_CLIENT_CERTIFICATE,
                     SSL_R_BAD_DATA_RETURNED_BY_CALLBACK);
          }
  
          X509_free(x509);
          EVP_PKEY_free(pkey);
          if (i && !ssl3_check_client_certificate(s))
              i = 0;
          if (i == 0) {
              if (s->version == SSL3_VERSION) {
                  s->s3->tmp.cert_req = 0;
                  ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_CERTIFICATE);
                  return WORK_FINISHED_CONTINUE;
              } else {
                  s->s3->tmp.cert_req = 2;
                  if (!ssl3_digest_cached_records(s, 0)) {
                      /* SSLfatal() already called */
                      return WORK_ERROR;
                  }
              }
          }
  
          if (s->post_handshake_auth == SSL_PHA_REQUESTED)
              return WORK_FINISHED_STOP;
          return WORK_FINISHED_CONTINUE;
      }
  
      /* Shouldn't ever get here */
      SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PREPARE_CLIENT_CERTIFICATE,
               ERR_R_INTERNAL_ERROR);
      return WORK_ERROR;
  }
  
  int tls_construct_client_certificate(SSL *s, WPACKET *pkt)
  {
      if (SSL_IS_TLS13(s)) {
          if (s->pha_context == NULL) {
              /* no context available, add 0-length context */
              if (!WPACKET_put_bytes_u8(pkt, 0)) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_CONSTRUCT_CLIENT_CERTIFICATE, ERR_R_INTERNAL_ERROR);
                  return 0;
              }
          } else if (!WPACKET_sub_memcpy_u8(pkt, s->pha_context, s->pha_context_len)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CLIENT_CERTIFICATE, ERR_R_INTERNAL_ERROR);
              return 0;
          }
      }
      if (!ssl3_output_cert_chain(s, pkt,
                                  (s->s3->tmp.cert_req == 2) ? NULL
                                                             : s->cert->key)) {
          /* SSLfatal() already called */
          return 0;
      }
  
      if (SSL_IS_TLS13(s)
              && SSL_IS_FIRST_HANDSHAKE(s)
              && (!s->method->ssl3_enc->change_cipher_state(s,
                      SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_CLIENT_WRITE))) {
          /*
           * This is a fatal error, which leaves enc_write_ctx in an inconsistent
           * state and thus ssl3_send_alert may crash.
           */
          SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_TLS_CONSTRUCT_CLIENT_CERTIFICATE,
                   SSL_R_CANNOT_CHANGE_CIPHER);
          return 0;
      }
  
      return 1;
  }
  
  int ssl3_check_cert_and_algorithm(SSL *s)
  {
      const SSL_CERT_LOOKUP *clu;
      size_t idx;
      long alg_k, alg_a;
  
      alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
      alg_a = s->s3->tmp.new_cipher->algorithm_auth;
  
      /* we don't have a certificate */
      if (!(alg_a & SSL_aCERT))
          return 1;
  
      /* This is the passed certificate */
      clu = ssl_cert_lookup_by_pkey(X509_get0_pubkey(s->session->peer), &idx);
  
      /* Check certificate is recognised and suitable for cipher */
      if (clu == NULL || (alg_a & clu->amask) == 0) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
                   SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM,
                   SSL_R_MISSING_SIGNING_CERT);
          return 0;
      }
  
  #ifndef OPENSSL_NO_EC
      if (clu->amask & SSL_aECDSA) {
          if (ssl_check_srvr_ecc_cert_and_alg(s->session->peer, s))
              return 1;
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
                   SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM, SSL_R_BAD_ECC_CERT);
          return 0;
      }
  #endif
  #ifndef OPENSSL_NO_RSA
      if (alg_k & (SSL_kRSA | SSL_kRSAPSK) && idx != SSL_PKEY_RSA) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
                   SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM,
                   SSL_R_MISSING_RSA_ENCRYPTING_CERT);
          return 0;
      }
  #endif
  #ifndef OPENSSL_NO_DH
      if ((alg_k & SSL_kDHE) && (s->s3->peer_tmp == NULL)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  #endif
  
      return 1;
  }
  
  #ifndef OPENSSL_NO_NEXTPROTONEG
  int tls_construct_next_proto(SSL *s, WPACKET *pkt)
  {
      size_t len, padding_len;
      unsigned char *padding = NULL;
  
      len = s->ext.npn_len;
      padding_len = 32 - ((len + 2) % 32);
  
      if (!WPACKET_sub_memcpy_u8(pkt, s->ext.npn, len)
              || !WPACKET_sub_allocate_bytes_u8(pkt, padding_len, &padding)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEXT_PROTO,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      memset(padding, 0, padding_len);
  
      return 1;
  }
  #endif
  
  MSG_PROCESS_RETURN tls_process_hello_req(SSL *s, PACKET *pkt)
  {
      if (PACKET_remaining(pkt) > 0) {
          /* should contain no data */
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_HELLO_REQ,
                   SSL_R_LENGTH_MISMATCH);
          return MSG_PROCESS_ERROR;
      }
  
      if ((s->options & SSL_OP_NO_RENEGOTIATION)) {
          ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
          return MSG_PROCESS_FINISHED_READING;
      }
  
      /*
       * This is a historical discrepancy (not in the RFC) maintained for
       * compatibility reasons. If a TLS client receives a HelloRequest it will
       * attempt an abbreviated handshake. However if a DTLS client receives a
       * HelloRequest it will do a full handshake. Either behaviour is reasonable
       * but doing one for TLS and another for DTLS is odd.
       */
      if (SSL_IS_DTLS(s))
          SSL_renegotiate(s);
      else
          SSL_renegotiate_abbreviated(s);
  
      return MSG_PROCESS_FINISHED_READING;
  }
  
  static MSG_PROCESS_RETURN tls_process_encrypted_extensions(SSL *s, PACKET *pkt)
  {
      PACKET extensions;
      RAW_EXTENSION *rawexts = NULL;
  
      if (!PACKET_as_length_prefixed_2(pkt, &extensions)
              || PACKET_remaining(pkt) != 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_ENCRYPTED_EXTENSIONS,
                   SSL_R_LENGTH_MISMATCH);
          goto err;
      }
  
      if (!tls_collect_extensions(s, &extensions,
                                  SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS, &rawexts,
                                  NULL, 1)
              || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
                                           rawexts, NULL, 0, 1)) {
          /* SSLfatal() already called */
          goto err;
      }
  
      OPENSSL_free(rawexts);
      return MSG_PROCESS_CONTINUE_READING;
  
   err:
      OPENSSL_free(rawexts);
      return MSG_PROCESS_ERROR;
  }
  
  int ssl_do_client_cert_cb(SSL *s, X509 **px509, EVP_PKEY **ppkey)
  {
      int i = 0;
  #ifndef OPENSSL_NO_ENGINE
      if (s->ctx->client_cert_engine) {
          i = ENGINE_load_ssl_client_cert(s->ctx->client_cert_engine, s,
                                          SSL_get_client_CA_list(s),
                                          px509, ppkey, NULL, NULL, NULL);
          if (i != 0)
              return i;
      }
  #endif
      if (s->ctx->client_cert_cb)
          i = s->ctx->client_cert_cb(s, px509, ppkey);
      return i;
  }
  
  int ssl_cipher_list_to_bytes(SSL *s, STACK_OF(SSL_CIPHER) *sk, WPACKET *pkt)
  {
      int i;
      size_t totlen = 0, len, maxlen, maxverok = 0;
      int empty_reneg_info_scsv = !s->renegotiate;
  
      /* Set disabled masks for this session */
      if (!ssl_set_client_disabled(s)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_SSL_CIPHER_LIST_TO_BYTES,
                   SSL_R_NO_PROTOCOLS_AVAILABLE);
          return 0;
      }
  
      if (sk == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_SSL_CIPHER_LIST_TO_BYTES,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
  #ifdef OPENSSL_MAX_TLS1_2_CIPHER_LENGTH
  # if OPENSSL_MAX_TLS1_2_CIPHER_LENGTH < 6
  #  error Max cipher length too short
  # endif
      /*
       * Some servers hang if client hello > 256 bytes as hack workaround
       * chop number of supported ciphers to keep it well below this if we
       * use TLS v1.2
       */
      if (TLS1_get_version(s) >= TLS1_2_VERSION)
          maxlen = OPENSSL_MAX_TLS1_2_CIPHER_LENGTH & ~1;
      else
  #endif
          /* Maximum length that can be stored in 2 bytes. Length must be even */
          maxlen = 0xfffe;
  
      if (empty_reneg_info_scsv)
          maxlen -= 2;
      if (s->mode & SSL_MODE_SEND_FALLBACK_SCSV)
          maxlen -= 2;
  
      for (i = 0; i < sk_SSL_CIPHER_num(sk) && totlen < maxlen; i++) {
          const SSL_CIPHER *c;
  
          c = sk_SSL_CIPHER_value(sk, i);
          /* Skip disabled ciphers */
          if (ssl_cipher_disabled(s, c, SSL_SECOP_CIPHER_SUPPORTED, 0))
              continue;
  
          if (!s->method->put_cipher_by_char(c, pkt, &len)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_SSL_CIPHER_LIST_TO_BYTES,
                       ERR_R_INTERNAL_ERROR);
              return 0;
          }
  
          /* Sanity check that the maximum version we offer has ciphers enabled */
          if (!maxverok) {
              if (SSL_IS_DTLS(s)) {
                  if (DTLS_VERSION_GE(c->max_dtls, s->s3->tmp.max_ver)
                          && DTLS_VERSION_LE(c->min_dtls, s->s3->tmp.max_ver))
                      maxverok = 1;
              } else {
                  if (c->max_tls >= s->s3->tmp.max_ver
                          && c->min_tls <= s->s3->tmp.max_ver)
                      maxverok = 1;
              }
          }
  
          totlen += len;
      }
  
      if (totlen == 0 || !maxverok) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_SSL_CIPHER_LIST_TO_BYTES,
                   SSL_R_NO_CIPHERS_AVAILABLE);
  
          if (!maxverok)
              ERR_add_error_data(1, "No ciphers enabled for max supported "
                                    "SSL/TLS version");
  
          return 0;
      }
  
      if (totlen != 0) {
          if (empty_reneg_info_scsv) {
              static SSL_CIPHER scsv = {
                  0, NULL, NULL, SSL3_CK_SCSV, 0, 0, 0, 0, 0, 0, 0, 0, 0
              };
              if (!s->method->put_cipher_by_char(&scsv, pkt, &len)) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_SSL_CIPHER_LIST_TO_BYTES, ERR_R_INTERNAL_ERROR);
                  return 0;
              }
          }
          if (s->mode & SSL_MODE_SEND_FALLBACK_SCSV) {
              static SSL_CIPHER scsv = {
                  0, NULL, NULL, SSL3_CK_FALLBACK_SCSV, 0, 0, 0, 0, 0, 0, 0, 0, 0
              };
              if (!s->method->put_cipher_by_char(&scsv, pkt, &len)) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_SSL_CIPHER_LIST_TO_BYTES, ERR_R_INTERNAL_ERROR);
                  return 0;
              }
          }
      }
  
      return 1;
  }
  
  int tls_construct_end_of_early_data(SSL *s, WPACKET *pkt)
  {
      if (s->early_data_state != SSL_EARLY_DATA_WRITE_RETRY
              && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_END_OF_EARLY_DATA,
                   ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
          return 0;
      }
  
      s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
      return 1;
  }
  