text: /*
   * Copyright 2016-2017 The OpenSSL Project Authors. 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 <openssl/ocsp.h>
  #include "../ssl_locl.h"
  #include "internal/cryptlib.h"
  #include "statem_locl.h"
  
  EXT_RETURN tls_construct_ctos_renegotiate(SSL *s, WPACKET *pkt,
                                            unsigned int context, X509 *x,
                                            size_t chainidx)
  {
      /* Add RI if renegotiating */
      if (!s->renegotiate)
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_renegotiate)
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_sub_memcpy_u8(pkt, s->s3->previous_client_finished,
                                 s->s3->previous_client_finished_len)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_RENEGOTIATE,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  EXT_RETURN tls_construct_ctos_server_name(SSL *s, WPACKET *pkt,
                                            unsigned int context, X509 *x,
                                            size_t chainidx)
  {
      if (s->ext.hostname == NULL)
          return EXT_RETURN_NOT_SENT;
  
      /* Add TLS extension servername to the Client Hello message */
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_server_name)
                 /* Sub-packet for server_name extension */
              || !WPACKET_start_sub_packet_u16(pkt)
                 /* Sub-packet for servername list (always 1 hostname)*/
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_put_bytes_u8(pkt, TLSEXT_NAMETYPE_host_name)
              || !WPACKET_sub_memcpy_u16(pkt, s->ext.hostname,
                                         strlen(s->ext.hostname))
              || !WPACKET_close(pkt)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_SERVER_NAME,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  /* Push a Max Fragment Len extension into ClientHello */
  EXT_RETURN tls_construct_ctos_maxfragmentlen(SSL *s, WPACKET *pkt,
                                               unsigned int context, X509 *x,
                                               size_t chainidx)
  {
      if (s->ext.max_fragment_len_mode == TLSEXT_max_fragment_length_DISABLED)
          return EXT_RETURN_NOT_SENT;
  
      /* Add Max Fragment Length extension if client enabled it. */
      /*-
       * 4 bytes for this extension type and extension length
       * 1 byte for the Max Fragment Length code value.
       */
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_max_fragment_length)
              /* Sub-packet for Max Fragment Length extension (1 byte) */
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_put_bytes_u8(pkt, s->ext.max_fragment_len_mode)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_MAXFRAGMENTLEN, ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  #ifndef OPENSSL_NO_SRP
  EXT_RETURN tls_construct_ctos_srp(SSL *s, WPACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
      /* Add SRP username if there is one */
      if (s->srp_ctx.login == NULL)
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_srp)
                 /* Sub-packet for SRP extension */
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_start_sub_packet_u8(pkt)
                 /* login must not be zero...internal error if so */
              || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH)
              || !WPACKET_memcpy(pkt, s->srp_ctx.login,
                                 strlen(s->srp_ctx.login))
              || !WPACKET_close(pkt)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_SRP,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  #endif
  
  #ifndef OPENSSL_NO_EC
  static int use_ecc(SSL *s)
  {
      int i, end;
      unsigned long alg_k, alg_a;
      STACK_OF(SSL_CIPHER) *cipher_stack = NULL;
  
      /* See if we support any ECC ciphersuites */
      if (s->version == SSL3_VERSION)
          return 0;
  
      cipher_stack = SSL_get_ciphers(s);
      end = sk_SSL_CIPHER_num(cipher_stack);
      for (i = 0; i < end; i++) {
          const SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_stack, i);
  
          alg_k = c->algorithm_mkey;
          alg_a = c->algorithm_auth;
          if ((alg_k & (SSL_kECDHE | SSL_kECDHEPSK))
                  || (alg_a & SSL_aECDSA)
                  || c->min_tls >= TLS1_3_VERSION)
              return 1;
      }
  
      return 0;
  }
  
  EXT_RETURN tls_construct_ctos_ec_pt_formats(SSL *s, WPACKET *pkt,
                                              unsigned int context, X509 *x,
                                              size_t chainidx)
  {
      const unsigned char *pformats;
      size_t num_formats;
  
      if (!use_ecc(s))
          return EXT_RETURN_NOT_SENT;
  
      /* Add TLS extension ECPointFormats to the ClientHello message */
      tls1_get_formatlist(s, &pformats, &num_formats);
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_ec_point_formats)
                 /* Sub-packet for formats extension */
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_sub_memcpy_u8(pkt, pformats, num_formats)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_EC_PT_FORMATS, ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  EXT_RETURN tls_construct_ctos_supported_groups(SSL *s, WPACKET *pkt,
                                                 unsigned int context, X509 *x,
                                                 size_t chainidx)
  {
      const uint16_t *pgroups = NULL;
      size_t num_groups = 0, i;
  
      if (!use_ecc(s))
          return EXT_RETURN_NOT_SENT;
  
      /*
       * Add TLS extension supported_groups to the ClientHello message
       */
      /* TODO(TLS1.3): Add support for DHE groups */
      tls1_get_supported_groups(s, &pgroups, &num_groups);
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_groups)
                 /* Sub-packet for supported_groups extension */
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_start_sub_packet_u16(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_GROUPS,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
      /* Copy curve ID if supported */
      for (i = 0; i < num_groups; i++) {
          uint16_t ctmp = pgroups[i];
  
          if (tls_curve_allowed(s, ctmp, SSL_SECOP_CURVE_SUPPORTED)) {
              if (!WPACKET_put_bytes_u16(pkt, ctmp)) {
                      SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                               SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_GROUPS,
                               ERR_R_INTERNAL_ERROR);
                      return EXT_RETURN_FAIL;
                  }
          }
      }
      if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_GROUPS,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  #endif
  
  EXT_RETURN tls_construct_ctos_session_ticket(SSL *s, WPACKET *pkt,
                                               unsigned int context, X509 *x,
                                               size_t chainidx)
  {
      size_t ticklen;
  
      if (!tls_use_ticket(s))
          return EXT_RETURN_NOT_SENT;
  
      if (!s->new_session && s->session != NULL
              && s->session->ext.tick != NULL
              && s->session->ssl_version != TLS1_3_VERSION) {
          ticklen = s->session->ext.ticklen;
      } else if (s->session && s->ext.session_ticket != NULL
                 && s->ext.session_ticket->data != NULL) {
          ticklen = s->ext.session_ticket->length;
          s->session->ext.tick = OPENSSL_malloc(ticklen);
          if (s->session->ext.tick == NULL) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_SESSION_TICKET,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
          memcpy(s->session->ext.tick,
                 s->ext.session_ticket->data, ticklen);
          s->session->ext.ticklen = ticklen;
      } else {
          ticklen = 0;
      }
  
      if (ticklen == 0 && s->ext.session_ticket != NULL &&
              s->ext.session_ticket->data == NULL)
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_session_ticket)
              || !WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick, ticklen)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  EXT_RETURN tls_construct_ctos_sig_algs(SSL *s, WPACKET *pkt,
                                         unsigned int context, X509 *x,
                                         size_t chainidx)
  {
      size_t salglen;
      const uint16_t *salg;
  
      if (!SSL_CLIENT_USE_SIGALGS(s))
          return EXT_RETURN_NOT_SENT;
  
      salglen = tls12_get_psigalgs(s, 1, &salg);
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_signature_algorithms)
                 /* Sub-packet for sig-algs extension */
              || !WPACKET_start_sub_packet_u16(pkt)
                 /* Sub-packet for the actual list */
              || !WPACKET_start_sub_packet_u16(pkt)
              || !tls12_copy_sigalgs(s, pkt, salg, salglen)
              || !WPACKET_close(pkt)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_SIG_ALGS,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  #ifndef OPENSSL_NO_OCSP
  EXT_RETURN tls_construct_ctos_status_request(SSL *s, WPACKET *pkt,
                                               unsigned int context, X509 *x,
                                               size_t chainidx)
  {
      int i;
  
      /* This extension isn't defined for client Certificates */
      if (x != NULL)
          return EXT_RETURN_NOT_SENT;
  
      if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp)
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_status_request)
                 /* Sub-packet for status request extension */
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_put_bytes_u8(pkt, TLSEXT_STATUSTYPE_ocsp)
                 /* Sub-packet for the ids */
              || !WPACKET_start_sub_packet_u16(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
      for (i = 0; i < sk_OCSP_RESPID_num(s->ext.ocsp.ids); i++) {
          unsigned char *idbytes;
          OCSP_RESPID *id = sk_OCSP_RESPID_value(s->ext.ocsp.ids, i);
          int idlen = i2d_OCSP_RESPID(id, NULL);
  
          if (idlen <= 0
                     /* Sub-packet for an individual id */
                  || !WPACKET_sub_allocate_bytes_u16(pkt, idlen, &idbytes)
                  || i2d_OCSP_RESPID(id, &idbytes) != idlen) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
      }
      if (!WPACKET_close(pkt)
              || !WPACKET_start_sub_packet_u16(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
      if (s->ext.ocsp.exts) {
          unsigned char *extbytes;
          int extlen = i2d_X509_EXTENSIONS(s->ext.ocsp.exts, NULL);
  
          if (extlen < 0) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
          if (!WPACKET_allocate_bytes(pkt, extlen, &extbytes)
                  || i2d_X509_EXTENSIONS(s->ext.ocsp.exts, &extbytes)
                     != extlen) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
         }
      }
      if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  #endif
  
  #ifndef OPENSSL_NO_NEXTPROTONEG
  EXT_RETURN tls_construct_ctos_npn(SSL *s, WPACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
      if (s->ctx->ext.npn_select_cb == NULL || !SSL_IS_FIRST_HANDSHAKE(s))
          return EXT_RETURN_NOT_SENT;
  
      /*
       * The client advertises an empty extension to indicate its support
       * for Next Protocol Negotiation
       */
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_next_proto_neg)
              || !WPACKET_put_bytes_u16(pkt, 0)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_NPN,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  #endif
  
  EXT_RETURN tls_construct_ctos_alpn(SSL *s, WPACKET *pkt, unsigned int context,
                                     X509 *x, size_t chainidx)
  {
      s->s3->alpn_sent = 0;
  
      if (s->ext.alpn == NULL || !SSL_IS_FIRST_HANDSHAKE(s))
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt,
                  TLSEXT_TYPE_application_layer_protocol_negotiation)
                 /* Sub-packet ALPN extension */
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_sub_memcpy_u16(pkt, s->ext.alpn, s->ext.alpn_len)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_ALPN,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
      s->s3->alpn_sent = 1;
  
      return EXT_RETURN_SENT;
  }
  
  
  #ifndef OPENSSL_NO_SRTP
  EXT_RETURN tls_construct_ctos_use_srtp(SSL *s, WPACKET *pkt,
                                         unsigned int context, X509 *x,
                                         size_t chainidx)
  {
      STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = SSL_get_srtp_profiles(s);
      int i, end;
  
      if (clnt == NULL)
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_use_srtp)
                 /* Sub-packet for SRTP extension */
              || !WPACKET_start_sub_packet_u16(pkt)
                 /* Sub-packet for the protection profile list */
              || !WPACKET_start_sub_packet_u16(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_USE_SRTP,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      end = sk_SRTP_PROTECTION_PROFILE_num(clnt);
      for (i = 0; i < end; i++) {
          const SRTP_PROTECTION_PROFILE *prof =
              sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
  
          if (prof == NULL || !WPACKET_put_bytes_u16(pkt, prof->id)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_USE_SRTP, ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
      }
      if (!WPACKET_close(pkt)
                 /* Add an empty use_mki value */
              || !WPACKET_put_bytes_u8(pkt, 0)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_USE_SRTP,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  #endif
  
  EXT_RETURN tls_construct_ctos_etm(SSL *s, WPACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
      if (s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_encrypt_then_mac)
              || !WPACKET_put_bytes_u16(pkt, 0)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_ETM,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  #ifndef OPENSSL_NO_CT
  EXT_RETURN tls_construct_ctos_sct(SSL *s, WPACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
      if (s->ct_validation_callback == NULL)
          return EXT_RETURN_NOT_SENT;
  
      /* Not defined for client Certificates */
      if (x != NULL)
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_signed_certificate_timestamp)
              || !WPACKET_put_bytes_u16(pkt, 0)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_SCT,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  #endif
  
  EXT_RETURN tls_construct_ctos_ems(SSL *s, WPACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_extended_master_secret)
              || !WPACKET_put_bytes_u16(pkt, 0)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_EMS,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  EXT_RETURN tls_construct_ctos_supported_versions(SSL *s, WPACKET *pkt,
                                                   unsigned int context, X509 *x,
                                                   size_t chainidx)
  {
      int currv, min_version, max_version, reason;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_versions)
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_start_sub_packet_u8(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      reason = ssl_get_min_max_version(s, &min_version, &max_version);
      if (reason != 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS, reason);
          return EXT_RETURN_FAIL;
      }
  
      /*
       * TODO(TLS1.3): There is some discussion on the TLS list as to whether
       * we should include versions <TLS1.2. For the moment we do. To be
       * reviewed later.
       */
      for (currv = max_version; currv >= min_version; currv--) {
          /* TODO(TLS1.3): Remove this first if clause prior to release!! */
          if (currv == TLS1_3_VERSION) {
              if (!WPACKET_put_bytes_u16(pkt, TLS1_3_VERSION_DRAFT)) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                           SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS,
                           ERR_R_INTERNAL_ERROR);
                  return EXT_RETURN_FAIL;
              }
          } else if (!WPACKET_put_bytes_u16(pkt, currv)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
      }
      if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      return EXT_RETURN_SENT;
  }
  
  /*
   * Construct a psk_kex_modes extension.
   */
  EXT_RETURN tls_construct_ctos_psk_kex_modes(SSL *s, WPACKET *pkt,
                                              unsigned int context, X509 *x,
                                              size_t chainidx)
  {
  #ifndef OPENSSL_NO_TLS1_3
      int nodhe = s->options & SSL_OP_ALLOW_NO_DHE_KEX;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk_kex_modes)
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_start_sub_packet_u8(pkt)
              || !WPACKET_put_bytes_u8(pkt, TLSEXT_KEX_MODE_KE_DHE)
              || (nodhe && !WPACKET_put_bytes_u8(pkt, TLSEXT_KEX_MODE_KE))
              || !WPACKET_close(pkt)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                   SSL_F_TLS_CONSTRUCT_CTOS_PSK_KEX_MODES, ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_KE_DHE;
      if (nodhe)
          s->ext.psk_kex_mode |= TLSEXT_KEX_MODE_FLAG_KE;
  #endif
  
      return EXT_RETURN_SENT;
  }
  
  #ifndef OPENSSL_NO_TLS1_3
  static int add_key_share(SSL *s, WPACKET *pkt, unsigned int curve_id)
  {
      unsigned char *encoded_point = NULL;
      EVP_PKEY *key_share_key = NULL;
      size_t encodedlen;
  
      if (s->s3->tmp.pkey != NULL) {
          if (!ossl_assert(s->hello_retry_request)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_ADD_KEY_SHARE,
                       ERR_R_INTERNAL_ERROR);
              return 0;
          }
          /*
           * Could happen if we got an HRR that wasn't requesting a new key_share
           */
          key_share_key = s->s3->tmp.pkey;
      } else {
          key_share_key = ssl_generate_pkey_group(s, curve_id);
          if (key_share_key == NULL) {
              /* SSLfatal() already called */
              return 0;
          }
      }
  
      /* Encode the public key. */
      encodedlen = EVP_PKEY_get1_tls_encodedpoint(key_share_key,
                                                  &encoded_point);
      if (encodedlen == 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_ADD_KEY_SHARE, ERR_R_EC_LIB);
          goto err;
      }
  
      /* Create KeyShareEntry */
      if (!WPACKET_put_bytes_u16(pkt, curve_id)
              || !WPACKET_sub_memcpy_u16(pkt, encoded_point, encodedlen)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_ADD_KEY_SHARE,
                   ERR_R_INTERNAL_ERROR);
          goto err;
      }
  
      /*
       * TODO(TLS1.3): When changing to send more than one key_share we're
       * going to need to be able to save more than one EVP_PKEY. For now
       * we reuse the existing tmp.pkey
       */
      s->s3->tmp.pkey = key_share_key;
      s->s3->group_id = curve_id;
      OPENSSL_free(encoded_point);
  
      return 1;
   err:
      if (s->s3->tmp.pkey == NULL)
          EVP_PKEY_free(key_share_key);
      OPENSSL_free(encoded_point);
      return 0;
  }
  #endif
  
  EXT_RETURN tls_construct_ctos_key_share(SSL *s, WPACKET *pkt,
                                          unsigned int context, X509 *x,
                                          size_t chainidx)
  {
  #ifndef OPENSSL_NO_TLS1_3
      size_t i, num_groups = 0;
      const uint16_t *pgroups = NULL;
      uint16_t curve_id = 0;
  
      /* key_share extension */
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_key_share)
                 /* Extension data sub-packet */
              || !WPACKET_start_sub_packet_u16(pkt)
                 /* KeyShare list sub-packet */
              || !WPACKET_start_sub_packet_u16(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      tls1_get_supported_groups(s, &pgroups, &num_groups);
  
      /*
       * TODO(TLS1.3): Make the number of key_shares sent configurable. For
       * now, just send one
       */
      if (s->s3->group_id != 0) {
          curve_id = s->s3->group_id;
      } else {
          for (i = 0; i < num_groups; i++) {
  
              if (!tls_curve_allowed(s, pgroups[i], SSL_SECOP_CURVE_SUPPORTED))
                  continue;
  
              curve_id = pgroups[i];
              break;
          }
      }
  
      if (curve_id == 0) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE,
                   SSL_R_NO_SUITABLE_KEY_SHARE);
          return EXT_RETURN_FAIL;
      }
  
      if (!add_key_share(s, pkt, curve_id)) {
          /* SSLfatal() already called */
          return EXT_RETURN_FAIL;
      }
  
      if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  #endif
  
      return EXT_RETURN_SENT;
  }
  
  EXT_RETURN tls_construct_ctos_cookie(SSL *s, WPACKET *pkt, unsigned int context,
                                       X509 *x, size_t chainidx)
  {
      EXT_RETURN ret = EXT_RETURN_FAIL;
  
      /* Should only be set if we've had an HRR */
      if (s->ext.tls13_cookie_len == 0)
          return EXT_RETURN_NOT_SENT;
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_cookie)
                 /* Extension data sub-packet */
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_sub_memcpy_u16(pkt, s->ext.tls13_cookie,
                                         s->ext.tls13_cookie_len)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_COOKIE,
                   ERR_R_INTERNAL_ERROR);
          goto end;
      }
  
      ret = EXT_RETURN_SENT;
   end:
      OPENSSL_free(s->ext.tls13_cookie);
      s->ext.tls13_cookie = NULL;
      s->ext.tls13_cookie_len = 0;
  
      return ret;
  }
  
  EXT_RETURN tls_construct_ctos_early_data(SSL *s, WPACKET *pkt,
                                           unsigned int context, X509 *x,
                                           size_t chainidx)
  {
      const unsigned char *id = NULL;
      size_t idlen = 0;
      SSL_SESSION *psksess = NULL;
      SSL_SESSION *edsess = NULL;
      const EVP_MD *handmd = NULL;
  
      if (s->hello_retry_request)
          handmd = ssl_handshake_md(s);
  
      if (s->psk_use_session_cb != NULL
              && (!s->psk_use_session_cb(s, handmd, &id, &idlen, &psksess)
                  || (psksess != NULL
                      && psksess->ssl_version != TLS1_3_VERSION))) {
          SSL_SESSION_free(psksess);
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_EARLY_DATA,
                   SSL_R_BAD_PSK);
          return EXT_RETURN_FAIL;
      }
  
      SSL_SESSION_free(s->psksession);
      s->psksession = psksess;
      if (psksess != NULL) {
          OPENSSL_free(s->psksession_id);
          s->psksession_id = OPENSSL_memdup(id, idlen);
          if (s->psksession_id == NULL) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_EARLY_DATA, ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
          s->psksession_id_len = idlen;
      }
  
      if (s->early_data_state != SSL_EARLY_DATA_CONNECTING
              || (s->session->ext.max_early_data == 0
                  && (psksess == NULL || psksess->ext.max_early_data == 0))) {
          s->max_early_data = 0;
          return EXT_RETURN_NOT_SENT;
      }
      edsess = s->session->ext.max_early_data != 0 ? s->session : psksess;
      s->max_early_data = edsess->ext.max_early_data;
  
      if (edsess->ext.hostname != NULL) {
          if (s->ext.hostname == NULL
                  || (s->ext.hostname != NULL
                      && strcmp(s->ext.hostname, edsess->ext.hostname) != 0)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_EARLY_DATA,
                       SSL_R_INCONSISTENT_EARLY_DATA_SNI);
              return EXT_RETURN_FAIL;
          }
      }
  
      if ((s->ext.alpn == NULL && edsess->ext.alpn_selected != NULL)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_EARLY_DATA,
                   SSL_R_INCONSISTENT_EARLY_DATA_ALPN);
          return EXT_RETURN_FAIL;
      }
  
      /*
       * Verify that we are offering an ALPN protocol consistent with the early
       * data.
       */
      if (edsess->ext.alpn_selected != NULL) {
          PACKET prots, alpnpkt;
          int found = 0;
  
          if (!PACKET_buf_init(&prots, s->ext.alpn, s->ext.alpn_len)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_EARLY_DATA, ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
          while (PACKET_get_length_prefixed_1(&prots, &alpnpkt)) {
              if (PACKET_equal(&alpnpkt, edsess->ext.alpn_selected,
                               edsess->ext.alpn_selected_len)) {
                  found = 1;
                  break;
              }
          }
          if (!found) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_CONSTRUCT_CTOS_EARLY_DATA,
                       SSL_R_INCONSISTENT_EARLY_DATA_ALPN);
              return EXT_RETURN_FAIL;
          }
      }
  
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_early_data)
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_close(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_EARLY_DATA,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      /*
       * We set this to rejected here. Later, if the server acknowledges the
       * extension, we set it to accepted.
       */
      s->ext.early_data = SSL_EARLY_DATA_REJECTED;
      s->ext.early_data_ok = 1;
  
      return EXT_RETURN_SENT;
  }
  
  #define F5_WORKAROUND_MIN_MSG_LEN   0xff
  #define F5_WORKAROUND_MAX_MSG_LEN   0x200
  
  /*
   * PSK pre binder overhead =
   *  2 bytes for TLSEXT_TYPE_psk
   *  2 bytes for extension length
   *  2 bytes for identities list length
   *  2 bytes for identity length
   *  4 bytes for obfuscated_ticket_age
   *  2 bytes for binder list length
   *  1 byte for binder length
   * The above excludes the number of bytes for the identity itself and the
   * subsequent binder bytes
   */
  #define PSK_PRE_BINDER_OVERHEAD (2 + 2 + 2 + 2 + 4 + 2 + 1)
  
  EXT_RETURN tls_construct_ctos_padding(SSL *s, WPACKET *pkt,
                                        unsigned int context, X509 *x,
                                        size_t chainidx)
  {
      unsigned char *padbytes;
      size_t hlen;
  
      if ((s->options & SSL_OP_TLSEXT_PADDING) == 0)
          return EXT_RETURN_NOT_SENT;
  
      /*
       * Add padding to workaround bugs in F5 terminators. See RFC7685.
       * This code calculates the length of all extensions added so far but
       * excludes the PSK extension (because that MUST be written last). Therefore
       * this extension MUST always appear second to last.
       */
      if (!WPACKET_get_total_written(pkt, &hlen)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PADDING,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      /*
       * If we're going to send a PSK then that will be written out after this
       * extension, so we need to calculate how long it is going to be.
       */
      if (s->session->ssl_version == TLS1_3_VERSION
              && s->session->ext.ticklen != 0
              && s->session->cipher != NULL) {
          const EVP_MD *md = ssl_md(s->session->cipher->algorithm2);
  
          if (md != NULL) {
              /*
               * Add the fixed PSK overhead, the identity length and the binder
               * length.
               */
              hlen +=  PSK_PRE_BINDER_OVERHEAD + s->session->ext.ticklen
                       + EVP_MD_size(md);
          }
      }
  
      if (hlen > F5_WORKAROUND_MIN_MSG_LEN && hlen < F5_WORKAROUND_MAX_MSG_LEN) {
          /* Calculate the amount of padding we need to add */
          hlen = F5_WORKAROUND_MAX_MSG_LEN - hlen;
  
          /*
           * Take off the size of extension header itself (2 bytes for type and
           * 2 bytes for length bytes), but ensure that the extension is at least
           * 1 byte long so as not to have an empty extension last (WebSphere 7.x,
           * 8.x are intolerant of that condition)
           */
          if (hlen > 4)
              hlen -= 4;
          else
              hlen = 1;
  
          if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_padding)
                  || !WPACKET_sub_allocate_bytes_u16(pkt, hlen, &padbytes)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PADDING,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
          memset(padbytes, 0, hlen);
      }
  
      return EXT_RETURN_SENT;
  }
  
  /*
   * Construct the pre_shared_key extension
   */
  EXT_RETURN tls_construct_ctos_psk(SSL *s, WPACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
  #ifndef OPENSSL_NO_TLS1_3
      uint32_t now, agesec, agems = 0;
      size_t reshashsize = 0, pskhashsize = 0, binderoffset, msglen;
      unsigned char *resbinder = NULL, *pskbinder = NULL, *msgstart = NULL;
      const EVP_MD *handmd = NULL, *mdres = NULL, *mdpsk = NULL;
      int dores = 0;
  
      s->session->ext.tick_identity = TLSEXT_PSK_BAD_IDENTITY;
  
      /*
       * Note: At this stage of the code we only support adding a single
       * resumption PSK. If we add support for multiple PSKs then the length
       * calculations in the padding extension will need to be adjusted.
       */
  
      /*
       * If this is an incompatible or new session then we have nothing to resume
       * so don't add this extension.
       */
      if (s->session->ssl_version != TLS1_3_VERSION
              || (s->session->ext.ticklen == 0 && s->psksession == NULL))
          return EXT_RETURN_NOT_SENT;
  
      if (s->hello_retry_request)
          handmd = ssl_handshake_md(s);
  
      if (s->session->ext.ticklen != 0) {
          /* Get the digest associated with the ciphersuite in the session */
          if (s->session->cipher == NULL) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PSK,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
          mdres = ssl_md(s->session->cipher->algorithm2);
          if (mdres == NULL) {
              /*
               * Don't recognize this cipher so we can't use the session.
               * Ignore it
               */
              goto dopsksess;
          }
  
          if (s->hello_retry_request && mdres != handmd) {
              /*
               * Selected ciphersuite hash does not match the hash for the session
               * so we can't use it.
               */
              goto dopsksess;
          }
  
          /*
           * Technically the C standard just says time() returns a time_t and says
           * nothing about the encoding of that type. In practice most
           * implementations follow POSIX which holds it as an integral type in
           * seconds since epoch. We've already made the assumption that we can do
           * this in multiple places in the code, so portability shouldn't be an
           * issue.
           */
          now = (uint32_t)time(NULL);
          agesec = now - (uint32_t)s->session->time;
  
          if (s->session->ext.tick_lifetime_hint < agesec) {
              /* Ticket is too old. Ignore it. */
              goto dopsksess;
          }
  
          /*
           * Calculate age in ms. We're just doing it to nearest second. Should be
           * good enough.
           */
          agems = agesec * (uint32_t)1000;
  
          if (agesec != 0 && agems / (uint32_t)1000 != agesec) {
              /*
               * Overflow. Shouldn't happen unless this is a *really* old session.
               * If so we just ignore it.
               */
              goto dopsksess;
          }
  
          /*
           * Obfuscate the age. Overflow here is fine, this addition is supposed
           * to be mod 2^32.
           */
          agems += s->session->ext.tick_age_add;
  
          reshashsize = EVP_MD_size(mdres);
          dores = 1;
      }
  
   dopsksess:
      if (!dores && s->psksession == NULL)
          return EXT_RETURN_NOT_SENT;
  
      if (s->psksession != NULL) {
          mdpsk = ssl_md(s->psksession->cipher->algorithm2);
          if (mdpsk == NULL) {
              /*
               * Don't recognize this cipher so we can't use the session.
               * If this happens it's an application bug.
               */
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PSK,
                       SSL_R_BAD_PSK);
              return EXT_RETURN_FAIL;
          }
  
          if (s->hello_retry_request && mdpsk != handmd) {
              /*
               * Selected ciphersuite hash does not match the hash for the PSK
               * session. This is an application bug.
               */
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PSK,
                       SSL_R_BAD_PSK);
              return EXT_RETURN_FAIL;
          }
  
          pskhashsize = EVP_MD_size(mdpsk);
      }
  
      /* Create the extension, but skip over the binder for now */
      if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk)
              || !WPACKET_start_sub_packet_u16(pkt)
              || !WPACKET_start_sub_packet_u16(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PSK,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      if (dores) {
          if (!WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick,
                                             s->session->ext.ticklen)
                  || !WPACKET_put_bytes_u32(pkt, agems)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PSK,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
      }
  
      if (s->psksession != NULL) {
          if (!WPACKET_sub_memcpy_u16(pkt, s->psksession_id,
                                      s->psksession_id_len)
                  || !WPACKET_put_bytes_u32(pkt, 0)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PSK,
                       ERR_R_INTERNAL_ERROR);
              return EXT_RETURN_FAIL;
          }
      }
  
      if (!WPACKET_close(pkt)
              || !WPACKET_get_total_written(pkt, &binderoffset)
              || !WPACKET_start_sub_packet_u16(pkt)
              || (dores
                  && !WPACKET_sub_allocate_bytes_u8(pkt, reshashsize, &resbinder))
              || (s->psksession != NULL
                  && !WPACKET_sub_allocate_bytes_u8(pkt, pskhashsize, &pskbinder))
              || !WPACKET_close(pkt)
              || !WPACKET_close(pkt)
              || !WPACKET_get_total_written(pkt, &msglen)
                 /*
                  * We need to fill in all the sub-packet lengths now so we can
                  * calculate the HMAC of the message up to the binders
                  */
              || !WPACKET_fill_lengths(pkt)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CTOS_PSK,
                   ERR_R_INTERNAL_ERROR);
          return EXT_RETURN_FAIL;
      }
  
      msgstart = WPACKET_get_curr(pkt) - msglen;
  
      if (dores
              && tls_psk_do_binder(s, mdres, msgstart, binderoffset, NULL,
                                   resbinder, s->session, 1, 0) != 1) {
          /* SSLfatal() already called */
          return EXT_RETURN_FAIL;
      }
  
      if (s->psksession != NULL
              && tls_psk_do_binder(s, mdpsk, msgstart, binderoffset, NULL,
                                   pskbinder, s->psksession, 1, 1) != 1) {
          /* SSLfatal() already called */
          return EXT_RETURN_FAIL;
      }
  
      if (dores)
          s->session->ext.tick_identity = 0;
      if (s->psksession != NULL)
          s->psksession->ext.tick_identity = (dores ? 1 : 0);
  
      return EXT_RETURN_SENT;
  #else
      return EXT_RETURN_NOT_SENT;
  #endif
  }
  
  /*
   * Parse the server's renegotiation binding and abort if it's not right
   */
  int tls_parse_stoc_renegotiate(SSL *s, PACKET *pkt, unsigned int context,
                                 X509 *x, size_t chainidx)
  {
      size_t expected_len = s->s3->previous_client_finished_len
          + s->s3->previous_server_finished_len;
      size_t ilen;
      const unsigned char *data;
  
      /* Check for logic errors */
      if (!ossl_assert(expected_len == 0
                       || s->s3->previous_client_finished_len != 0)
          || !ossl_assert(expected_len == 0
                          || s->s3->previous_server_finished_len != 0)) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_RENEGOTIATE,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      /* Parse the length byte */
      if (!PACKET_get_1_len(pkt, &ilen)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_RENEGOTIATE,
                   SSL_R_RENEGOTIATION_ENCODING_ERR);
          return 0;
      }
  
      /* Consistency check */
      if (PACKET_remaining(pkt) != ilen) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_RENEGOTIATE,
                   SSL_R_RENEGOTIATION_ENCODING_ERR);
          return 0;
      }
  
      /* Check that the extension matches */
      if (ilen != expected_len) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PARSE_STOC_RENEGOTIATE,
                   SSL_R_RENEGOTIATION_MISMATCH);
          return 0;
      }
  
      if (!PACKET_get_bytes(pkt, &data, s->s3->previous_client_finished_len)
          || memcmp(data, s->s3->previous_client_finished,
                    s->s3->previous_client_finished_len) != 0) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PARSE_STOC_RENEGOTIATE,
                   SSL_R_RENEGOTIATION_MISMATCH);
          return 0;
      }
  
      if (!PACKET_get_bytes(pkt, &data, s->s3->previous_server_finished_len)
          || memcmp(data, s->s3->previous_server_finished,
                    s->s3->previous_server_finished_len) != 0) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PARSE_STOC_RENEGOTIATE,
                   SSL_R_RENEGOTIATION_MISMATCH);
          return 0;
      }
      s->s3->send_connection_binding = 1;
  
      return 1;
  }
  
  /* Parse the server's max fragment len extension packet */
  int tls_parse_stoc_maxfragmentlen(SSL *s, PACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
      unsigned int value;
  
      if (PACKET_remaining(pkt) != 1 || !PACKET_get_1(pkt, &value)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_MAXFRAGMENTLEN, 
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      /* |value| should contains a valid max-fragment-length code. */
      if (!IS_MAX_FRAGMENT_LENGTH_EXT_VALID(value)) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                   SSL_F_TLS_PARSE_STOC_MAXFRAGMENTLEN,
                   SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH);
          return 0;
      }
  
      /* Must be the same value as client-configured one who was sent to server */
      /*-
       * RFC 6066: if a client receives a maximum fragment length negotiation
       * response that differs from the length it requested, ...
       * It must abort with SSL_AD_ILLEGAL_PARAMETER alert
       */
      if (value != s->ext.max_fragment_len_mode) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                   SSL_F_TLS_PARSE_STOC_MAXFRAGMENTLEN,
                   SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH);
          return 0;
      }
  
      /*
       * Maximum Fragment Length Negotiation succeeded.
       * The negotiated Maximum Fragment Length is binding now.
       */
      s->session->ext.max_fragment_len_mode = value;
  
      return 1;
  }
  
  int tls_parse_stoc_server_name(SSL *s, PACKET *pkt, unsigned int context,
                                 X509 *x, size_t chainidx)
  {
      if (s->ext.hostname == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_SERVER_NAME,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      if (PACKET_remaining(pkt) > 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_SERVER_NAME,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      if (!s->hit) {
          if (s->session->ext.hostname != NULL) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_SERVER_NAME,
                       ERR_R_INTERNAL_ERROR);
              return 0;
          }
          s->session->ext.hostname = OPENSSL_strdup(s->ext.hostname);
          if (s->session->ext.hostname == NULL) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_SERVER_NAME,
                       ERR_R_INTERNAL_ERROR);
              return 0;
          }
      }
  
      return 1;
  }
  
  #ifndef OPENSSL_NO_EC
  int tls_parse_stoc_ec_pt_formats(SSL *s, PACKET *pkt, unsigned int context,
                                   X509 *x, size_t chainidx)
  {
      unsigned int ecpointformats_len;
      PACKET ecptformatlist;
  
      if (!PACKET_as_length_prefixed_1(pkt, &ecptformatlist)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_EC_PT_FORMATS,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
      if (!s->hit) {
          ecpointformats_len = PACKET_remaining(&ecptformatlist);
          s->session->ext.ecpointformats_len = 0;
  
          OPENSSL_free(s->session->ext.ecpointformats);
          s->session->ext.ecpointformats = OPENSSL_malloc(ecpointformats_len);
          if (s->session->ext.ecpointformats == NULL) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_PARSE_STOC_EC_PT_FORMATS, ERR_R_INTERNAL_ERROR);
              return 0;
          }
  
          s->session->ext.ecpointformats_len = ecpointformats_len;
  
          if (!PACKET_copy_bytes(&ecptformatlist,
                                 s->session->ext.ecpointformats,
                                 ecpointformats_len)) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR,
                       SSL_F_TLS_PARSE_STOC_EC_PT_FORMATS, ERR_R_INTERNAL_ERROR);
              return 0;
          }
      }
  
      return 1;
  }
  #endif
  
  int tls_parse_stoc_session_ticket(SSL *s, PACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
      if (s->ext.session_ticket_cb != NULL &&
          !s->ext.session_ticket_cb(s, PACKET_data(pkt),
                                PACKET_remaining(pkt),
                                s->ext.session_ticket_cb_arg)) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
                   SSL_F_TLS_PARSE_STOC_SESSION_TICKET, SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      if (!tls_use_ticket(s)) {
          SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION,
                   SSL_F_TLS_PARSE_STOC_SESSION_TICKET, SSL_R_BAD_EXTENSION);
          return 0;
      }
      if (PACKET_remaining(pkt) > 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR,
                   SSL_F_TLS_PARSE_STOC_SESSION_TICKET, SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      s->ext.ticket_expected = 1;
  
      return 1;
  }
  
  #ifndef OPENSSL_NO_OCSP
  int tls_parse_stoc_status_request(SSL *s, PACKET *pkt, unsigned int context,
                                    X509 *x, size_t chainidx)
  {
      /*
       * MUST only be sent if we've requested a status
       * request message. In TLS <= 1.2 it must also be empty.
       */
      if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp) {
          SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION,
                   SSL_F_TLS_PARSE_STOC_STATUS_REQUEST, SSL_R_BAD_EXTENSION);
          return 0;
      }
      if (!SSL_IS_TLS13(s) && PACKET_remaining(pkt) > 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR,
                   SSL_F_TLS_PARSE_STOC_STATUS_REQUEST, SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      if (SSL_IS_TLS13(s)) {
          /* We only know how to handle this if it's for the first Certificate in
           * the chain. We ignore any other responses.
           */
          if (chainidx != 0)
              return 1;
  
          /* SSLfatal() already called */
          return tls_process_cert_status_body(s, pkt);
      }
  
      /* Set flag to expect CertificateStatus message */
      s->ext.status_expected = 1;
  
      return 1;
  }
  #endif
  
  
  #ifndef OPENSSL_NO_CT
  int tls_parse_stoc_sct(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                         size_t chainidx)
  {
      /*
       * Only take it if we asked for it - i.e if there is no CT validation
       * callback set, then a custom extension MAY be processing it, so we
       * need to let control continue to flow to that.
       */
      if (s->ct_validation_callback != NULL) {
          size_t size = PACKET_remaining(pkt);
  
          /* Simply copy it off for later processing */
          OPENSSL_free(s->ext.scts);
          s->ext.scts = NULL;
  
          s->ext.scts_len = (uint16_t)size;
          if (size > 0) {
              s->ext.scts = OPENSSL_malloc(size);
              if (s->ext.scts == NULL
                      || !PACKET_copy_bytes(pkt, s->ext.scts, size)) {
                  SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_SCT,
                           ERR_R_INTERNAL_ERROR);
                  return 0;
              }
          }
      } else {
          ENDPOINT role = (context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0
                          ? ENDPOINT_CLIENT : ENDPOINT_BOTH;
  
          /*
           * If we didn't ask for it then there must be a custom extension,
           * otherwise this is unsolicited.
           */
          if (custom_ext_find(&s->cert->custext, role,
                              TLSEXT_TYPE_signed_certificate_timestamp,
                              NULL) == NULL) {
              SSLfatal(s, TLS1_AD_UNSUPPORTED_EXTENSION, SSL_F_TLS_PARSE_STOC_SCT,
                       SSL_R_BAD_EXTENSION);
              return 0;
          }
  
          if (!custom_ext_parse(s, context,
                               TLSEXT_TYPE_signed_certificate_timestamp,
                               PACKET_data(pkt), PACKET_remaining(pkt),
                               x, chainidx)) {
              /* SSLfatal already called */
              return 0;
          }
      }
  
      return 1;
  }
  #endif
  
  
  #ifndef OPENSSL_NO_NEXTPROTONEG
  /*
   * ssl_next_proto_validate validates a Next Protocol Negotiation block. No
   * elements of zero length are allowed and the set of elements must exactly
   * fill the length of the block. Returns 1 on success or 0 on failure.
   */
  static int ssl_next_proto_validate(SSL *s, PACKET *pkt)
  {
      PACKET tmp_protocol;
  
      while (PACKET_remaining(pkt)) {
          if (!PACKET_get_length_prefixed_1(pkt, &tmp_protocol)
              || PACKET_remaining(&tmp_protocol) == 0) {
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_SSL_NEXT_PROTO_VALIDATE,
                       SSL_R_BAD_EXTENSION);
              return 0;
          }
      }
  
      return 1;
  }
  
  int tls_parse_stoc_npn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                         size_t chainidx)
  {
      unsigned char *selected;
      unsigned char selected_len;
      PACKET tmppkt;
  
      /* Check if we are in a renegotiation. If so ignore this extension */
      if (!SSL_IS_FIRST_HANDSHAKE(s))
          return 1;
  
      /* We must have requested it. */
      if (s->ctx->ext.npn_select_cb == NULL) {
          SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_F_TLS_PARSE_STOC_NPN,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      /* The data must be valid */
      tmppkt = *pkt;
      if (!ssl_next_proto_validate(s, &tmppkt)) {
          /* SSLfatal() already called */
          return 0;
      }
      if (s->ctx->ext.npn_select_cb(s, &selected, &selected_len,
                                    PACKET_data(pkt),
                                    PACKET_remaining(pkt),
                                    s->ctx->ext.npn_select_cb_arg) !=
               SSL_TLSEXT_ERR_OK) {
          SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_PARSE_STOC_NPN,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      /*
       * Could be non-NULL if server has sent multiple NPN extensions in
       * a single Serverhello
       */
      OPENSSL_free(s->ext.npn);
      s->ext.npn = OPENSSL_malloc(selected_len);
      if (s->ext.npn == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_NPN,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      memcpy(s->ext.npn, selected, selected_len);
      s->ext.npn_len = selected_len;
      s->s3->npn_seen = 1;
  
      return 1;
  }
  #endif
  
  int tls_parse_stoc_alpn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                          size_t chainidx)
  {
      size_t len;
  
      /* We must have requested it. */
      if (!s->s3->alpn_sent) {
          SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_F_TLS_PARSE_STOC_ALPN,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
      /*-
       * The extension data consists of:
       *   uint16 list_length
       *   uint8 proto_length;
       *   uint8 proto[proto_length];
       */
      if (!PACKET_get_net_2_len(pkt, &len)
          || PACKET_remaining(pkt) != len || !PACKET_get_1_len(pkt, &len)
          || PACKET_remaining(pkt) != len) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_ALPN,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
      OPENSSL_free(s->s3->alpn_selected);
      s->s3->alpn_selected = OPENSSL_malloc(len);
      if (s->s3->alpn_selected == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_ALPN,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
      if (!PACKET_copy_bytes(pkt, s->s3->alpn_selected, len)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_ALPN,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
      s->s3->alpn_selected_len = len;
  
      if (s->session->ext.alpn_selected == NULL
              || s->session->ext.alpn_selected_len != len
              || memcmp(s->session->ext.alpn_selected, s->s3->alpn_selected, len)
                 != 0) {
          /* ALPN not consistent with the old session so cannot use early_data */
          s->ext.early_data_ok = 0;
      }
      if (!s->hit) {
          /* If a new session then update it with the selected ALPN */
          s->session->ext.alpn_selected =
              OPENSSL_memdup(s->s3->alpn_selected, s->s3->alpn_selected_len);
          if (s->session->ext.alpn_selected == NULL) {
              SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_ALPN,
                       ERR_R_INTERNAL_ERROR);
              return 0;
          }
          s->session->ext.alpn_selected_len = s->s3->alpn_selected_len;
      }
  
      return 1;
  }
  
  #ifndef OPENSSL_NO_SRTP
  int tls_parse_stoc_use_srtp(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                              size_t chainidx)
  {
      unsigned int id, ct, mki;
      int i;
      STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
      SRTP_PROTECTION_PROFILE *prof;
  
      if (!PACKET_get_net_2(pkt, &ct) || ct != 2
              || !PACKET_get_net_2(pkt, &id)
              || !PACKET_get_1(pkt, &mki)
              || PACKET_remaining(pkt) != 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_USE_SRTP,
                   SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
          return 0;
      }
  
      if (mki != 0) {
          /* Must be no MKI, since we never offer one */
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PARSE_STOC_USE_SRTP,
                   SSL_R_BAD_SRTP_MKI_VALUE);
          return 0;
      }
  
      /* Throw an error if the server gave us an unsolicited extension */
      clnt = SSL_get_srtp_profiles(s);
      if (clnt == NULL) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_USE_SRTP,
                   SSL_R_NO_SRTP_PROFILES);
          return 0;
      }
  
      /*
       * Check to see if the server gave us something we support (and
       * presumably offered)
       */
      for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) {
          prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
  
          if (prof->id == id) {
              s->srtp_profile = prof;
              return 1;
          }
      }
  
      SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_USE_SRTP,
               SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
      return 0;
  }
  #endif
  
  int tls_parse_stoc_etm(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                         size_t chainidx)
  {
      /* Ignore if inappropriate ciphersuite */
      if (!(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)
              && s->s3->tmp.new_cipher->algorithm_mac != SSL_AEAD
              && s->s3->tmp.new_cipher->algorithm_enc != SSL_RC4)
          s->ext.use_etm = 1;
  
      return 1;
  }
  
  int tls_parse_stoc_ems(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                         size_t chainidx)
  {
      s->s3->flags |= TLS1_FLAGS_RECEIVED_EXTMS;
      if (!s->hit)
          s->session->flags |= SSL_SESS_FLAG_EXTMS;
  
      return 1;
  }
  
  int tls_parse_stoc_key_share(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                               size_t chainidx)
  {
  #ifndef OPENSSL_NO_TLS1_3
      unsigned int group_id;
      PACKET encoded_pt;
      EVP_PKEY *ckey = s->s3->tmp.pkey, *skey = NULL;
  
      /* Sanity check */
      if (ckey == NULL || s->s3->peer_tmp != NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_KEY_SHARE,
                   ERR_R_INTERNAL_ERROR);
          return 0;
      }
  
      if (!PACKET_get_net_2(pkt, &group_id)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_KEY_SHARE,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      if ((context & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0) {
          const uint16_t *pgroups = NULL;
          size_t i, num_groups;
  
          if (PACKET_remaining(pkt) != 0) {
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_KEY_SHARE,
                       SSL_R_LENGTH_MISMATCH);
              return 0;
          }
  
          /*
           * It is an error if the HelloRetryRequest wants a key_share that we
           * already sent in the first ClientHello
           */
          if (group_id == s->s3->group_id) {
              SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                       SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
              return 0;
          }
  
          /* Validate the selected group is one we support */
          tls1_get_supported_groups(s, &pgroups, &num_groups);
          for (i = 0; i < num_groups; i++) {
              if (group_id == pgroups[i])
                  break;
          }
          if (i >= num_groups
                  || !tls_curve_allowed(s, group_id, SSL_SECOP_CURVE_SUPPORTED)) {
              SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
                       SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
              return 0;
          }
  
          s->s3->group_id = group_id;
          EVP_PKEY_free(s->s3->tmp.pkey);
          s->s3->tmp.pkey = NULL;
          return 1;
      }
  
      if (group_id != s->s3->group_id) {
          /*
           * This isn't for the group that we sent in the original
           * key_share!
           */
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PARSE_STOC_KEY_SHARE,
                   SSL_R_BAD_KEY_SHARE);
          return 0;
      }
  
      if (!PACKET_as_length_prefixed_2(pkt, &encoded_pt)
              || PACKET_remaining(&encoded_pt) == 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_KEY_SHARE,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      skey = ssl_generate_pkey(ckey);
      if (skey == NULL) {
          SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_STOC_KEY_SHARE,
                   ERR_R_MALLOC_FAILURE);
          return 0;
      }
      if (!EVP_PKEY_set1_tls_encodedpoint(skey, PACKET_data(&encoded_pt),
                                          PACKET_remaining(&encoded_pt))) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PARSE_STOC_KEY_SHARE,
                   SSL_R_BAD_ECPOINT);
          EVP_PKEY_free(skey);
          return 0;
      }
  
      if (ssl_derive(s, ckey, skey, 1) == 0) {
          /* SSLfatal() already called */
          EVP_PKEY_free(skey);
          return 0;
      }
      s->s3->peer_tmp = skey;
  #endif
  
      return 1;
  }
  
  int tls_parse_stoc_cookie(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                         size_t chainidx)
  {
      PACKET cookie;
  
      if (!PACKET_as_length_prefixed_2(pkt, &cookie)
              || !PACKET_memdup(&cookie, &s->ext.tls13_cookie,
                                &s->ext.tls13_cookie_len)) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_COOKIE,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      return 1;
  }
  
  int tls_parse_stoc_early_data(SSL *s, PACKET *pkt, unsigned int context,
                                X509 *x, size_t chainidx)
  {
      if (context == SSL_EXT_TLS1_3_NEW_SESSION_TICKET) {
          unsigned long max_early_data;
  
          if (!PACKET_get_net_4(pkt, &max_early_data)
                  || PACKET_remaining(pkt) != 0) {
              SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_EARLY_DATA,
                       SSL_R_INVALID_MAX_EARLY_DATA);
              return 0;
          }
  
          s->session->ext.max_early_data = max_early_data;
  
          return 1;
      }
  
      if (PACKET_remaining(pkt) != 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_EARLY_DATA,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      if (!s->ext.early_data_ok
              || !s->hit
              || s->session->ext.tick_identity != 0) {
          /*
           * If we get here then we didn't send early data, or we didn't resume
           * using the first identity, or the SNI/ALPN is not consistent so the
           * server should not be accepting it.
           */
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PARSE_STOC_EARLY_DATA,
                   SSL_R_BAD_EXTENSION);
          return 0;
      }
  
      s->ext.early_data = SSL_EARLY_DATA_ACCEPTED;
  
      return 1;
  }
  
  int tls_parse_stoc_psk(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
                         size_t chainidx)
  {
  #ifndef OPENSSL_NO_TLS1_3
      unsigned int identity;
  
      if (!PACKET_get_net_2(pkt, &identity) || PACKET_remaining(pkt) != 0) {
          SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_STOC_PSK,
                   SSL_R_LENGTH_MISMATCH);
          return 0;
      }
  
      if (s->session->ext.tick_identity == (int)identity) {
          s->hit = 1;
          SSL_SESSION_free(s->psksession);
          s->psksession = NULL;
          return 1;
      }
  
      if (s->psksession == NULL
              || s->psksession->ext.tick_identity != (int)identity) {
          SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PARSE_STOC_PSK,
                   SSL_R_BAD_PSK_IDENTITY);
          return 0;
      }
  
      /*
       * If we used the external PSK for sending early_data then s->early_secret
       * is already set up, so don't overwrite it. Otherwise we copy the
       * early_secret across that we generated earlier.
       */
      if ((s->early_data_state != SSL_EARLY_DATA_WRITE_RETRY
                  && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING)
              || s->session->ext.max_early_data > 0
              || s->psksession->ext.max_early_data == 0)
          memcpy(s->early_secret, s->psksession->early_secret, EVP_MAX_MD_SIZE);
  
      SSL_SESSION_free(s->session);
      s->session = s->psksession;
      s->psksession = NULL;
      s->hit = 1;
  #endif
  
      return 1;
  }
  