text: /*
   * Copyright 1995-2019 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
   */
  
  /* callback functions used by s_client, s_server, and s_time */
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h> /* for memcpy() and strcmp() */
  #include "apps.h"
  #include <openssl/err.h>
  #include <openssl/rand.h>
  #include <openssl/x509.h>
  #include <openssl/ssl.h>
  #include <openssl/bn.h>
  #ifndef OPENSSL_NO_DH
  # include <openssl/dh.h>
  #endif
  #include <oqs/oqs.h>
  #include "s_apps.h"
  
  #define COOKIE_SECRET_LENGTH    16
  
  VERIFY_CB_ARGS verify_args = { -1, 0, X509_V_OK, 0 };
  
  #ifndef OPENSSL_NO_SOCK
  static unsigned char cookie_secret[COOKIE_SECRET_LENGTH];
  static int cookie_initialized = 0;
  #endif
  static BIO *bio_keylog = NULL;
  
  static const char *lookup(int val, const STRINT_PAIR* list, const char* def)
  {
      for ( ; list->name; ++list)
          if (list->retval == val)
              return list->name;
      return def;
  }
  
  int verify_callback(int ok, X509_STORE_CTX *ctx)
  {
      X509 *err_cert;
      int err, depth;
  
      err_cert = X509_STORE_CTX_get_current_cert(ctx);
      err = X509_STORE_CTX_get_error(ctx);
      depth = X509_STORE_CTX_get_error_depth(ctx);
  
      if (!verify_args.quiet || !ok) {
          BIO_printf(bio_err, "depth=%d ", depth);
          if (err_cert != NULL) {
              X509_NAME_print_ex(bio_err,
                                 X509_get_subject_name(err_cert),
                                 0, get_nameopt());
              BIO_puts(bio_err, "\n");
          } else {
              BIO_puts(bio_err, "<no cert>\n");
          }
      }
      if (!ok) {
          BIO_printf(bio_err, "verify error:num=%d:%s\n", err,
                     X509_verify_cert_error_string(err));
          if (verify_args.depth < 0 || verify_args.depth >= depth) {
              if (!verify_args.return_error)
                  ok = 1;
              verify_args.error = err;
          } else {
              ok = 0;
              verify_args.error = X509_V_ERR_CERT_CHAIN_TOO_LONG;
          }
      }
      switch (err) {
      case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
          BIO_puts(bio_err, "issuer= ");
          X509_NAME_print_ex(bio_err, X509_get_issuer_name(err_cert),
                             0, get_nameopt());
          BIO_puts(bio_err, "\n");
          break;
      case X509_V_ERR_CERT_NOT_YET_VALID:
      case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
          BIO_printf(bio_err, "notBefore=");
          ASN1_TIME_print(bio_err, X509_get0_notBefore(err_cert));
          BIO_printf(bio_err, "\n");
          break;
      case X509_V_ERR_CERT_HAS_EXPIRED:
      case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
          BIO_printf(bio_err, "notAfter=");
          ASN1_TIME_print(bio_err, X509_get0_notAfter(err_cert));
          BIO_printf(bio_err, "\n");
          break;
      case X509_V_ERR_NO_EXPLICIT_POLICY:
          if (!verify_args.quiet)
              policies_print(ctx);
          break;
      }
      if (err == X509_V_OK && ok == 2 && !verify_args.quiet)
          policies_print(ctx);
      if (ok && !verify_args.quiet)
          BIO_printf(bio_err, "verify return:%d\n", ok);
      return ok;
  }
  
  int set_cert_stuff(SSL_CTX *ctx, char *cert_file, char *key_file)
  {
      if (cert_file != NULL) {
          if (SSL_CTX_use_certificate_file(ctx, cert_file,
                                           SSL_FILETYPE_PEM) <= 0) {
              BIO_printf(bio_err, "unable to get certificate from '%s'\n",
                         cert_file);
              ERR_print_errors(bio_err);
              return 0;
          }
          if (key_file == NULL)
              key_file = cert_file;
          if (SSL_CTX_use_PrivateKey_file(ctx, key_file, SSL_FILETYPE_PEM) <= 0) {
              BIO_printf(bio_err, "unable to get private key from '%s'\n",
                         key_file);
              ERR_print_errors(bio_err);
              return 0;
          }
  
          /*
           * If we are using DSA, we can copy the parameters from the private
           * key
           */
  
          /*
           * Now we know that a key and cert have been set against the SSL
           * context
           */
          if (!SSL_CTX_check_private_key(ctx)) {
              BIO_printf(bio_err,
                         "Private key does not match the certificate public key\n");
              return 0;
          }
      }
      return 1;
  }
  
  int set_cert_key_stuff(SSL_CTX *ctx, X509 *cert, EVP_PKEY *key,
                         STACK_OF(X509) *chain, int build_chain)
  {
      int chflags = chain ? SSL_BUILD_CHAIN_FLAG_CHECK : 0;
      if (cert == NULL)
          return 1;
      if (SSL_CTX_use_certificate(ctx, cert) <= 0) {
          BIO_printf(bio_err, "error setting certificate\n");
          ERR_print_errors(bio_err);
          return 0;
      }
  
      if (SSL_CTX_use_PrivateKey(ctx, key) <= 0) {
          BIO_printf(bio_err, "error setting private key\n");
          ERR_print_errors(bio_err);
          return 0;
      }
  
      /*
       * Now we know that a key and cert have been set against the SSL context
       */
      if (!SSL_CTX_check_private_key(ctx)) {
          BIO_printf(bio_err,
                     "Private key does not match the certificate public key\n");
          return 0;
      }
      if (chain && !SSL_CTX_set1_chain(ctx, chain)) {
          BIO_printf(bio_err, "error setting certificate chain\n");
          ERR_print_errors(bio_err);
          return 0;
      }
      if (build_chain && !SSL_CTX_build_cert_chain(ctx, chflags)) {
          BIO_printf(bio_err, "error building certificate chain\n");
          ERR_print_errors(bio_err);
          return 0;
      }
      return 1;
  }
  
  static STRINT_PAIR cert_type_list[] = {
      {"RSA sign", TLS_CT_RSA_SIGN},
      {"DSA sign", TLS_CT_DSS_SIGN},
      {"RSA fixed DH", TLS_CT_RSA_FIXED_DH},
      {"DSS fixed DH", TLS_CT_DSS_FIXED_DH},
      {"ECDSA sign", TLS_CT_ECDSA_SIGN},
      {"RSA fixed ECDH", TLS_CT_RSA_FIXED_ECDH},
      {"ECDSA fixed ECDH", TLS_CT_ECDSA_FIXED_ECDH},
      {"GOST01 Sign", TLS_CT_GOST01_SIGN},
      {NULL}
  };
  
  static void ssl_print_client_cert_types(BIO *bio, SSL *s)
  {
      const unsigned char *p;
      int i;
      int cert_type_num = SSL_get0_certificate_types(s, &p);
      if (!cert_type_num)
          return;
      BIO_puts(bio, "Client Certificate Types: ");
      for (i = 0; i < cert_type_num; i++) {
          unsigned char cert_type = p[i];
          const char *cname = lookup((int)cert_type, cert_type_list, NULL);
  
          if (i)
              BIO_puts(bio, ", ");
          if (cname != NULL)
              BIO_puts(bio, cname);
          else
              BIO_printf(bio, "UNKNOWN (%d),", cert_type);
      }
      BIO_puts(bio, "\n");
  }
  
  static const char *get_sigtype(int nid)
  {
      switch (nid) {
      case EVP_PKEY_RSA:
          return "RSA";
  
      case EVP_PKEY_RSA_PSS:
          return "RSA-PSS";
  
      case EVP_PKEY_DSA:
          return "DSA";
  
       case EVP_PKEY_EC:
          return "ECDSA";
  
       case NID_ED25519:
          return "Ed25519";
  
       case NID_ED448:
          return "Ed448";
  
       case NID_id_GostR3410_2001:
          return "gost2001";
  
       case NID_id_GostR3410_2012_256:
          return "gost2012_256";
  
       case NID_id_GostR3410_2012_512:
          return "gost2012_512";
  
  #if !defined(OQS_NIST_BRANCH)
       /* OQS sig schemes */
       case NID_picnicL1FS:
          return "Picnic L1 FS";
       case NID_qteslaI:
          return "qTESLA-I";
       case NID_qteslaIIIsize:
          return "qTESLA-III-size";
       case NID_qteslaIIIspeed:
          return "qTESLA-III-speed";
       case NID_dilithium2:
          return "Dilithium-2";
       case NID_dilithium3:
          return "Dilithium-3";
       case NID_dilithium4:
          return "Dilithium-4"; 
       /* ADD_MORE_OQS_SIG_HERE */
       case NID_p256_picnicL1FS:
          return "ECDSA p256 - Picnic L1 FS";
       case NID_rsa3072_picnicL1FS:
          return "RSA3072 - Picnic L1 FS";
       case NID_p256_qteslaI:
          return "ECDSA p256 - qTESLA-I";
       case NID_rsa3072_qteslaI:
          return "RSA3072 - qTESLA-I";
       case NID_p384_qteslaIIIsize:
          return "ECDSA p384 - qTESLA-III-size";
       case NID_p384_qteslaIIIspeed:
          return "ECDSA p384 - qTESLA-III-speed";
       /* ADD_MORE_OQS_SIG_HERE hybrid only */
  #endif
      default:
          return NULL;
      }
  }
  
  static int do_print_sigalgs(BIO *out, SSL *s, int shared)
  {
      int i, nsig, client;
      client = SSL_is_server(s) ? 0 : 1;
      if (shared)
          nsig = SSL_get_shared_sigalgs(s, 0, NULL, NULL, NULL, NULL, NULL);
      else
          nsig = SSL_get_sigalgs(s, -1, NULL, NULL, NULL, NULL, NULL);
      if (nsig == 0)
          return 1;
  
      if (shared)
          BIO_puts(out, "Shared ");
  
      if (client)
          BIO_puts(out, "Requested ");
      BIO_puts(out, "Signature Algorithms: ");
      for (i = 0; i < nsig; i++) {
          int hash_nid, sign_nid;
          unsigned char rhash, rsign;
          const char *sstr = NULL;
          if (shared)
              SSL_get_shared_sigalgs(s, i, &sign_nid, &hash_nid, NULL,
                                     &rsign, &rhash);
          else
              SSL_get_sigalgs(s, i, &sign_nid, &hash_nid, NULL, &rsign, &rhash);
          if (i)
              BIO_puts(out, ":");
          sstr = get_sigtype(sign_nid);
          if (sstr)
              BIO_printf(out, "%s", sstr);
          else
              BIO_printf(out, "0x%02X", (int)rsign);
          if (hash_nid != NID_undef)
              BIO_printf(out, "+%s", OBJ_nid2sn(hash_nid));
          else if (sstr == NULL)
              BIO_printf(out, "+0x%02X", (int)rhash);
      }
      BIO_puts(out, "\n");
      return 1;
  }
  
  int ssl_print_sigalgs(BIO *out, SSL *s)
  {
      int nid;
      if (!SSL_is_server(s))
          ssl_print_client_cert_types(out, s);
      do_print_sigalgs(out, s, 0);
      do_print_sigalgs(out, s, 1);
      if (SSL_get_peer_signature_nid(s, &nid) && nid != NID_undef)
          BIO_printf(out, "Peer signing digest: %s\n", OBJ_nid2sn(nid));
      if (SSL_get_peer_signature_type_nid(s, &nid))
          BIO_printf(out, "Peer signature type: %s\n", get_sigtype(nid));
      return 1;
  }
  
  #ifndef OPENSSL_NO_EC
  int ssl_print_point_formats(BIO *out, SSL *s)
  {
      int i, nformats;
      const char *pformats;
      nformats = SSL_get0_ec_point_formats(s, &pformats);
      if (nformats <= 0)
          return 1;
      BIO_puts(out, "Supported Elliptic Curve Point Formats: ");
      for (i = 0; i < nformats; i++, pformats++) {
          if (i)
              BIO_puts(out, ":");
          switch (*pformats) {
          case TLSEXT_ECPOINTFORMAT_uncompressed:
              BIO_puts(out, "uncompressed");
              break;
  
          case TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime:
              BIO_puts(out, "ansiX962_compressed_prime");
              break;
  
          case TLSEXT_ECPOINTFORMAT_ansiX962_compressed_char2:
              BIO_puts(out, "ansiX962_compressed_char2");
              break;
  
          default:
              BIO_printf(out, "unknown(%d)", (int)*pformats);
              break;
  
          }
      }
      BIO_puts(out, "\n");
      return 1;
  }
  
  int ssl_print_groups(BIO *out, SSL *s, int noshared)
  {
      int i, ngroups, *groups, nid;
      const char *gname;
  
      ngroups = SSL_get1_groups(s, NULL);
      if (ngroups <= 0)
          return 1;
      groups = app_malloc(ngroups * sizeof(int), "groups to print");
      SSL_get1_groups(s, groups);
  
      BIO_puts(out, "Supported Elliptic Groups: ");
      for (i = 0; i < ngroups; i++) {
          if (i)
              BIO_puts(out, ":");
          nid = groups[i];
          /* If unrecognised print out hex version */
          if (nid & TLSEXT_nid_unknown) {
              BIO_printf(out, "0x%04X", nid & 0xFFFF);
          } else {
              /* TODO(TLS1.3): Get group name here */
              /* Use NIST name for curve if it exists */
              gname = EC_curve_nid2nist(nid);
              if (gname == NULL)
                  gname = OBJ_nid2sn(nid);
              BIO_printf(out, "%s", gname);
          }
      }
      OPENSSL_free(groups);
      if (noshared) {
          BIO_puts(out, "\n");
          return 1;
      }
      BIO_puts(out, "\nShared Elliptic groups: ");
      ngroups = SSL_get_shared_group(s, -1);
      for (i = 0; i < ngroups; i++) {
          if (i)
              BIO_puts(out, ":");
          nid = SSL_get_shared_group(s, i);
          /* TODO(TLS1.3): Convert for DH groups */
          gname = EC_curve_nid2nist(nid);
          if (gname == NULL)
              gname = OBJ_nid2sn(nid);
          BIO_printf(out, "%s", gname);
      }
      if (ngroups == 0)
          BIO_puts(out, "NONE");
      BIO_puts(out, "\n");
      return 1;
  }
  #endif
  
  /* OQS note: is there a better place to put this? we only need it here... */
  static const char* OQS_CURVE_ID_NAME_STR(int id) {
    switch(id) {
    case 0x01FF: return "oqs_kem_default";
    ///// OQS_TEMPLATE_FRAGMENT_OQS_CURVE_ID_NAME_STR_START
    case 0x0200: return "frodo640aes";
    case 0x0201: return "frodo640shake";
    case 0x0202: return "frodo976aes";
    case 0x0203: return "frodo976shake";
    case 0x0204: return "frodo1344aes";
    case 0x0205: return "frodo1344shake";
    case 0x0206: return "bike1l1";
    case 0x0207: return "bike1l3";
    case 0x0208: return "bike1l5";
    case 0x0209: return "bike2l1";
    case 0x020A: return "bike2l3";
    case 0x020B: return "bike2l5";
    case 0x020C: return "bike3l1";
    case 0x020D: return "bike3l3";
    case 0x020E: return "bike3l5";
    case 0x020F: return "kyber512";
    case 0x0210: return "kyber768";
    case 0x0211: return "kyber1024";
    case 0x0212: return "newhope512cca";
    case 0x0213: return "newhope1024cca";
    case 0x0214: return "ntru_hps2048509";
    case 0x0215: return "ntru_hps2048677";
    case 0x0216: return "ntru_hps4096821";
    case 0x0217: return "ntru_hrss701";
    case 0x0218: return "lightsaber";
    case 0x0219: return "saber";
    case 0x021A: return "firesaber";
    case 0x021B: return "sidhp434";
    case 0x021C: return "sidhp503";
    case 0x021D: return "sidhp610";
    case 0x021E: return "sidhp751";
    case 0x021F: return "sikep434";
    case 0x0220: return "sikep503";
    case 0x0221: return "sikep610";
    case 0x0222: return "sikep751";
    ///// OQS_TEMPLATE_FRAGMENT_OQS_CURVE_ID_NAME_STR_END
    case 0x02FF: return "p256-oqs_kem_default hybrid";
    ///// OQS_TEMPLATE_FRAGMENT_OQS_CURVE_ID_NAME_STR_HYBRID_START
    case 0x0300: return "p256-frodo640aes hybrid";
    case 0x0301: return "p256-frodo640shake hybrid";
    case 0x0302: return "p256-frodo976aes hybrid";
    case 0x0303: return "p256-frodo976shake hybrid";
    case 0x0304: return "p256-frodo1344aes hybrid";
    case 0x0305: return "p256-frodo1344shake hybrid";
    case 0x0306: return "p256-bike1l1 hybrid";
    case 0x0307: return "p256-bike1l3 hybrid";
    case 0x0308: return "p256-bike1l5 hybrid";
    case 0x0309: return "p256-bike2l1 hybrid";
    case 0x030A: return "p256-bike2l3 hybrid";
    case 0x030B: return "p256-bike2l5 hybrid";
    case 0x030C: return "p256-bike3l1 hybrid";
    case 0x030D: return "p256-bike3l3 hybrid";
    case 0x030E: return "p256-bike3l5 hybrid";
    case 0x030F: return "p256-kyber512 hybrid";
    case 0x0310: return "p256-kyber768 hybrid";
    case 0x0311: return "p256-kyber1024 hybrid";
    case 0x0312: return "p256-newhope512cca hybrid";
    case 0x0313: return "p256-newhope1024cca hybrid";
    case 0x0314: return "p256-ntru_hps2048509 hybrid";
    case 0x0315: return "p256-ntru_hps2048677 hybrid";
    case 0x0316: return "p256-ntru_hps4096821 hybrid";
    case 0x0317: return "p256-ntru_hrss701 hybrid";
    case 0x0318: return "p256-lightsaber hybrid";
    case 0x0319: return "p256-saber hybrid";
    case 0x031A: return "p256-firesaber hybrid";
    case 0x031B: return "p256-sidhp434 hybrid";
    case 0x031C: return "p256-sidhp503 hybrid";
    case 0x031D: return "p256-sidhp610 hybrid";
    case 0x031E: return "p256-sidhp751 hybrid";
    case 0x031F: return "p256-sikep434 hybrid";
    case 0x0320: return "p256-sikep503 hybrid";
    case 0x0321: return "p256-sikep610 hybrid";
    case 0x0322: return "p256-sikep751 hybrid";
    ///// OQS_TEMPLATE_FRAGMENT_OQS_CURVE_ID_NAME_STR_HYBRID_END
    default: return "";
    }
  }
  
  int ssl_print_tmp_key(BIO *out, SSL *s)
  {
      /* Special case for oqs key. Instead of relying on the peer key (s->s3->peer_tmp),
         we see if our special field is set (s->s3->tmp.oqs_kem_nid). This way, we won't
         have to modify the EVP api to set the key type (EVP_PKEY_assign). */
      EVP_PKEY *key;
      int oqs_kem_curve_id = SSL_get_oqs_kem_curve_id(s);
      if (oqs_kem_curve_id != 0) {
        BIO_printf(out, "Server Temp Key: %s\n", OQS_CURVE_ID_NAME_STR(oqs_kem_curve_id));
        return 1;
      }
      /* ------------- end oqs */
      if (!SSL_get_peer_tmp_key(s, &key))
          return 1;
      int nid_key = EVP_PKEY_id(key);
      BIO_puts(out, "Server Temp Key: ");
      switch (nid_key) {
      case EVP_PKEY_RSA:
          BIO_printf(out, "RSA, %d bits\n", EVP_PKEY_bits(key));
          break;
  
      case EVP_PKEY_DH:
          BIO_printf(out, "DH, %d bits\n", EVP_PKEY_bits(key));
          break;
  #ifndef OPENSSL_NO_EC
      case EVP_PKEY_EC:
          {
              EC_KEY *ec = EVP_PKEY_get1_EC_KEY(key);
              int nid;
              const char *cname;
              nid = EC_GROUP_get_curve_name(EC_KEY_get0_group(ec));
              EC_KEY_free(ec);
              cname = EC_curve_nid2nist(nid);
              if (cname == NULL)
                  cname = OBJ_nid2sn(nid);
              BIO_printf(out, "ECDH, %s, %d bits\n", cname, EVP_PKEY_bits(key));
          }
      break;
  #endif
      default:
        {
  	  BIO_printf(out, "%s, %d bits\n", OBJ_nid2sn(EVP_PKEY_id(key)),
                        EVP_PKEY_bits(key));
        }
      }
      EVP_PKEY_free(key);
      return 1;
  }
  
  long bio_dump_callback(BIO *bio, int cmd, const char *argp,
                         int argi, long argl, long ret)
  {
      BIO *out;
  
      out = (BIO *)BIO_get_callback_arg(bio);
      if (out == NULL)
          return ret;
  
      if (cmd == (BIO_CB_READ | BIO_CB_RETURN)) {
          BIO_printf(out, "read from %p [%p] (%lu bytes => %ld (0x%lX))\n",
                     (void *)bio, (void *)argp, (unsigned long)argi, ret, ret);
          BIO_dump(out, argp, (int)ret);
          return ret;
      } else if (cmd == (BIO_CB_WRITE | BIO_CB_RETURN)) {
          BIO_printf(out, "write to %p [%p] (%lu bytes => %ld (0x%lX))\n",
                     (void *)bio, (void *)argp, (unsigned long)argi, ret, ret);
          BIO_dump(out, argp, (int)ret);
      }
      return ret;
  }
  
  void apps_ssl_info_callback(const SSL *s, int where, int ret)
  {
      const char *str;
      int w;
  
      w = where & ~SSL_ST_MASK;
  
      if (w & SSL_ST_CONNECT)
          str = "SSL_connect";
      else if (w & SSL_ST_ACCEPT)
          str = "SSL_accept";
      else
          str = "undefined";
  
      if (where & SSL_CB_LOOP) {
          BIO_printf(bio_err, "%s:%s\n", str, SSL_state_string_long(s));
      } else if (where & SSL_CB_ALERT) {
          str = (where & SSL_CB_READ) ? "read" : "write";
          BIO_printf(bio_err, "SSL3 alert %s:%s:%s\n",
                     str,
                     SSL_alert_type_string_long(ret),
                     SSL_alert_desc_string_long(ret));
      } else if (where & SSL_CB_EXIT) {
          if (ret == 0)
              BIO_printf(bio_err, "%s:failed in %s\n",
                         str, SSL_state_string_long(s));
          else if (ret < 0)
              BIO_printf(bio_err, "%s:error in %s\n",
                         str, SSL_state_string_long(s));
      }
  }
  
  static STRINT_PAIR ssl_versions[] = {
      {"SSL 3.0", SSL3_VERSION},
      {"TLS 1.0", TLS1_VERSION},
      {"TLS 1.1", TLS1_1_VERSION},
      {"TLS 1.2", TLS1_2_VERSION},
      {"TLS 1.3", TLS1_3_VERSION},
      {"DTLS 1.0", DTLS1_VERSION},
      {"DTLS 1.0 (bad)", DTLS1_BAD_VER},
      {NULL}
  };
  
  static STRINT_PAIR alert_types[] = {
      {" close_notify", 0},
      {" end_of_early_data", 1},
      {" unexpected_message", 10},
      {" bad_record_mac", 20},
      {" decryption_failed", 21},
      {" record_overflow", 22},
      {" decompression_failure", 30},
      {" handshake_failure", 40},
      {" bad_certificate", 42},
      {" unsupported_certificate", 43},
      {" certificate_revoked", 44},
      {" certificate_expired", 45},
      {" certificate_unknown", 46},
      {" illegal_parameter", 47},
      {" unknown_ca", 48},
      {" access_denied", 49},
      {" decode_error", 50},
      {" decrypt_error", 51},
      {" export_restriction", 60},
      {" protocol_version", 70},
      {" insufficient_security", 71},
      {" internal_error", 80},
      {" inappropriate_fallback", 86},
      {" user_canceled", 90},
      {" no_renegotiation", 100},
      {" missing_extension", 109},
      {" unsupported_extension", 110},
      {" certificate_unobtainable", 111},
      {" unrecognized_name", 112},
      {" bad_certificate_status_response", 113},
      {" bad_certificate_hash_value", 114},
      {" unknown_psk_identity", 115},
      {" certificate_required", 116},
      {NULL}
  };
  
  static STRINT_PAIR handshakes[] = {
      {", HelloRequest", SSL3_MT_HELLO_REQUEST},
      {", ClientHello", SSL3_MT_CLIENT_HELLO},
      {", ServerHello", SSL3_MT_SERVER_HELLO},
      {", HelloVerifyRequest", DTLS1_MT_HELLO_VERIFY_REQUEST},
      {", NewSessionTicket", SSL3_MT_NEWSESSION_TICKET},
      {", EndOfEarlyData", SSL3_MT_END_OF_EARLY_DATA},
      {", EncryptedExtensions", SSL3_MT_ENCRYPTED_EXTENSIONS},
      {", Certificate", SSL3_MT_CERTIFICATE},
      {", ServerKeyExchange", SSL3_MT_SERVER_KEY_EXCHANGE},
      {", CertificateRequest", SSL3_MT_CERTIFICATE_REQUEST},
      {", ServerHelloDone", SSL3_MT_SERVER_DONE},
      {", CertificateVerify", SSL3_MT_CERTIFICATE_VERIFY},
      {", ClientKeyExchange", SSL3_MT_CLIENT_KEY_EXCHANGE},
      {", Finished", SSL3_MT_FINISHED},
      {", CertificateUrl", SSL3_MT_CERTIFICATE_URL},
      {", CertificateStatus", SSL3_MT_CERTIFICATE_STATUS},
      {", SupplementalData", SSL3_MT_SUPPLEMENTAL_DATA},
      {", KeyUpdate", SSL3_MT_KEY_UPDATE},
  #ifndef OPENSSL_NO_NEXTPROTONEG
      {", NextProto", SSL3_MT_NEXT_PROTO},
  #endif
      {", MessageHash", SSL3_MT_MESSAGE_HASH},
      {NULL}
  };
  
  void msg_cb(int write_p, int version, int content_type, const void *buf,
              size_t len, SSL *ssl, void *arg)
  {
      BIO *bio = arg;
      const char *str_write_p = write_p ? ">>>" : "<<<";
      const char *str_version = lookup(version, ssl_versions, "???");
      const char *str_content_type = "", *str_details1 = "", *str_details2 = "";
      const unsigned char* bp = buf;
  
      if (version == SSL3_VERSION ||
          version == TLS1_VERSION ||
          version == TLS1_1_VERSION ||
          version == TLS1_2_VERSION ||
          version == TLS1_3_VERSION ||
          version == DTLS1_VERSION || version == DTLS1_BAD_VER) {
          switch (content_type) {
          case 20:
              str_content_type = ", ChangeCipherSpec";
              break;
          case 21:
              str_content_type = ", Alert";
              str_details1 = ", ???";
              if (len == 2) {
                  switch (bp[0]) {
                  case 1:
                      str_details1 = ", warning";
                      break;
                  case 2:
                      str_details1 = ", fatal";
                      break;
                  }
                  str_details2 = lookup((int)bp[1], alert_types, " ???");
              }
              break;
          case 22:
              str_content_type = ", Handshake";
              str_details1 = "???";
              if (len > 0)
                  str_details1 = lookup((int)bp[0], handshakes, "???");
              break;
          case 23:
              str_content_type = ", ApplicationData";
              break;
  #ifndef OPENSSL_NO_HEARTBEATS
          case 24:
              str_details1 = ", Heartbeat";
  
              if (len > 0) {
                  switch (bp[0]) {
                  case 1:
                      str_details1 = ", HeartbeatRequest";
                      break;
                  case 2:
                      str_details1 = ", HeartbeatResponse";
                      break;
                  }
              }
              break;
  #endif
          }
      }
  
      BIO_printf(bio, "%s %s%s [length %04lx]%s%s\n", str_write_p, str_version,
                 str_content_type, (unsigned long)len, str_details1,
                 str_details2);
  
      if (len > 0) {
          size_t num, i;
  
          BIO_printf(bio, "   ");
          num = len;
          for (i = 0; i < num; i++) {
              if (i % 16 == 0 && i > 0)
                  BIO_printf(bio, "\n   ");
              BIO_printf(bio, " %02x", ((const unsigned char *)buf)[i]);
          }
          if (i < len)
              BIO_printf(bio, " ...");
          BIO_printf(bio, "\n");
      }
      (void)BIO_flush(bio);
  }
  
  static STRINT_PAIR tlsext_types[] = {
      {"server name", TLSEXT_TYPE_server_name},
      {"max fragment length", TLSEXT_TYPE_max_fragment_length},
      {"client certificate URL", TLSEXT_TYPE_client_certificate_url},
      {"trusted CA keys", TLSEXT_TYPE_trusted_ca_keys},
      {"truncated HMAC", TLSEXT_TYPE_truncated_hmac},
      {"status request", TLSEXT_TYPE_status_request},
      {"user mapping", TLSEXT_TYPE_user_mapping},
      {"client authz", TLSEXT_TYPE_client_authz},
      {"server authz", TLSEXT_TYPE_server_authz},
      {"cert type", TLSEXT_TYPE_cert_type},
      {"supported_groups", TLSEXT_TYPE_supported_groups},
      {"EC point formats", TLSEXT_TYPE_ec_point_formats},
      {"SRP", TLSEXT_TYPE_srp},
      {"signature algorithms", TLSEXT_TYPE_signature_algorithms},
      {"use SRTP", TLSEXT_TYPE_use_srtp},
      {"heartbeat", TLSEXT_TYPE_heartbeat},
      {"session ticket", TLSEXT_TYPE_session_ticket},
      {"renegotiation info", TLSEXT_TYPE_renegotiate},
      {"signed certificate timestamps", TLSEXT_TYPE_signed_certificate_timestamp},
      {"TLS padding", TLSEXT_TYPE_padding},
  #ifdef TLSEXT_TYPE_next_proto_neg
      {"next protocol", TLSEXT_TYPE_next_proto_neg},
  #endif
  #ifdef TLSEXT_TYPE_encrypt_then_mac
      {"encrypt-then-mac", TLSEXT_TYPE_encrypt_then_mac},
  #endif
  #ifdef TLSEXT_TYPE_application_layer_protocol_negotiation
      {"application layer protocol negotiation",
       TLSEXT_TYPE_application_layer_protocol_negotiation},
  #endif
  #ifdef TLSEXT_TYPE_extended_master_secret
      {"extended master secret", TLSEXT_TYPE_extended_master_secret},
  #endif
      {"key share", TLSEXT_TYPE_key_share},
      {"supported versions", TLSEXT_TYPE_supported_versions},
      {"psk", TLSEXT_TYPE_psk},
      {"psk kex modes", TLSEXT_TYPE_psk_kex_modes},
      {"certificate authorities", TLSEXT_TYPE_certificate_authorities},
      {"post handshake auth", TLSEXT_TYPE_post_handshake_auth},
      {NULL}
  };
  
  /* from rfc8446 4.2.3. + gost (https://tools.ietf.org/id/draft-smyshlyaev-tls12-gost-suites-04.html) */
  static STRINT_PAIR signature_tls13_scheme_list[] = {
      {"rsa_pkcs1_sha1",         0x0201 /* TLSEXT_SIGALG_rsa_pkcs1_sha1 */},
      {"ecdsa_sha1",             0x0203 /* TLSEXT_SIGALG_ecdsa_sha1 */},
  /*  {"rsa_pkcs1_sha224",       0x0301    TLSEXT_SIGALG_rsa_pkcs1_sha224}, not in rfc8446 */
  /*  {"ecdsa_sha224",           0x0303    TLSEXT_SIGALG_ecdsa_sha224}      not in rfc8446 */
      {"rsa_pkcs1_sha256",       0x0401 /* TLSEXT_SIGALG_rsa_pkcs1_sha256 */},
      {"ecdsa_secp256r1_sha256", 0x0403 /* TLSEXT_SIGALG_ecdsa_secp256r1_sha256 */},
      {"rsa_pkcs1_sha384",       0x0501 /* TLSEXT_SIGALG_rsa_pkcs1_sha384 */},
      {"ecdsa_secp384r1_sha384", 0x0503 /* TLSEXT_SIGALG_ecdsa_secp384r1_sha384 */},
      {"rsa_pkcs1_sha512",       0x0601 /* TLSEXT_SIGALG_rsa_pkcs1_sha512 */},
      {"ecdsa_secp521r1_sha512", 0x0603 /* TLSEXT_SIGALG_ecdsa_secp521r1_sha512 */},
      {"rsa_pss_rsae_sha256",    0x0804 /* TLSEXT_SIGALG_rsa_pss_rsae_sha256 */},
      {"rsa_pss_rsae_sha384",    0x0805 /* TLSEXT_SIGALG_rsa_pss_rsae_sha384 */},
      {"rsa_pss_rsae_sha512",    0x0806 /* TLSEXT_SIGALG_rsa_pss_rsae_sha512 */},
      {"ed25519",                0x0807 /* TLSEXT_SIGALG_ed25519 */},
      {"ed448",                  0x0808 /* TLSEXT_SIGALG_ed448 */},
      {"rsa_pss_pss_sha256",     0x0809 /* TLSEXT_SIGALG_rsa_pss_pss_sha256 */},
      {"rsa_pss_pss_sha384",     0x080a /* TLSEXT_SIGALG_rsa_pss_pss_sha384 */},
      {"rsa_pss_pss_sha512",     0x080b /* TLSEXT_SIGALG_rsa_pss_pss_sha512 */},
      {"gostr34102001",          0xeded /* TLSEXT_SIGALG_gostr34102001_gostr3411 */},
      {"gostr34102012_256",      0xeeee /* TLSEXT_SIGALG_gostr34102012_256_gostr34112012_256 */},
      {"gostr34102012_512",      0xefef /* TLSEXT_SIGALG_gostr34102012_512_gostr34112012_512 */},
      {NULL}
  };
  
  /* from rfc5246 7.4.1.4.1. */
  static STRINT_PAIR signature_tls12_alg_list[] = {
      {"anonymous", TLSEXT_signature_anonymous /* 0 */},
      {"RSA",       TLSEXT_signature_rsa       /* 1 */},
      {"DSA",       TLSEXT_signature_dsa       /* 2 */},
      {"ECDSA",     TLSEXT_signature_ecdsa     /* 3 */},
      {NULL}
  };
  
  /* from rfc5246 7.4.1.4.1. */
  static STRINT_PAIR signature_tls12_hash_list[] = {
      {"none",   TLSEXT_hash_none   /* 0 */},
      {"MD5",    TLSEXT_hash_md5    /* 1 */},
      {"SHA1",   TLSEXT_hash_sha1   /* 2 */},
      {"SHA224", TLSEXT_hash_sha224 /* 3 */},
      {"SHA256", TLSEXT_hash_sha256 /* 4 */},
      {"SHA384", TLSEXT_hash_sha384 /* 5 */},
      {"SHA512", TLSEXT_hash_sha512 /* 6 */},
      {NULL}
  };
  
  void tlsext_cb(SSL *s, int client_server, int type,
                 const unsigned char *data, int len, void *arg)
  {
      BIO *bio = arg;
      const char *extname = lookup(type, tlsext_types, "unknown");
  
      BIO_printf(bio, "TLS %s extension \"%s\" (id=%d), len=%d\n",
                 client_server ? "server" : "client", extname, type, len);
      BIO_dump(bio, (const char *)data, len);
      (void)BIO_flush(bio);
  }
  
  #ifndef OPENSSL_NO_SOCK
  int generate_cookie_callback(SSL *ssl, unsigned char *cookie,
                               unsigned int *cookie_len)
  {
      unsigned char *buffer;
      size_t length = 0;
      unsigned short port;
      BIO_ADDR *lpeer = NULL, *peer = NULL;
  
      /* Initialize a random secret */
      if (!cookie_initialized) {
          if (RAND_bytes(cookie_secret, COOKIE_SECRET_LENGTH) <= 0) {
              BIO_printf(bio_err, "error setting random cookie secret\n");
              return 0;
          }
          cookie_initialized = 1;
      }
  
      if (SSL_is_dtls(ssl)) {
          lpeer = peer = BIO_ADDR_new();
          if (peer == NULL) {
              BIO_printf(bio_err, "memory full\n");
              return 0;
          }
  
          /* Read peer information */
          (void)BIO_dgram_get_peer(SSL_get_rbio(ssl), peer);
      } else {
          peer = ourpeer;
      }
  
      /* Create buffer with peer's address and port */
      if (!BIO_ADDR_rawaddress(peer, NULL, &length)) {
          BIO_printf(bio_err, "Failed getting peer address\n");
          return 0;
      }
      OPENSSL_assert(length != 0);
      port = BIO_ADDR_rawport(peer);
      length += sizeof(port);
      buffer = app_malloc(length, "cookie generate buffer");
  
      memcpy(buffer, &port, sizeof(port));
      BIO_ADDR_rawaddress(peer, buffer + sizeof(port), NULL);
  
      /* Calculate HMAC of buffer using the secret */
      HMAC(EVP_sha1(), cookie_secret, COOKIE_SECRET_LENGTH,
           buffer, length, cookie, cookie_len);
  
      OPENSSL_free(buffer);
      BIO_ADDR_free(lpeer);
  
      return 1;
  }
  
  int verify_cookie_callback(SSL *ssl, const unsigned char *cookie,
                             unsigned int cookie_len)
  {
      unsigned char result[EVP_MAX_MD_SIZE];
      unsigned int resultlength;
  
      /* Note: we check cookie_initialized because if it's not,
       * it cannot be valid */
      if (cookie_initialized
          && generate_cookie_callback(ssl, result, &resultlength)
          && cookie_len == resultlength
          && memcmp(result, cookie, resultlength) == 0)
          return 1;
  
      return 0;
  }
  
  int generate_stateless_cookie_callback(SSL *ssl, unsigned char *cookie,
                                         size_t *cookie_len)
  {
      unsigned int temp;
      int res = generate_cookie_callback(ssl, cookie, &temp);
      *cookie_len = temp;
      return res;
  }
  
  int verify_stateless_cookie_callback(SSL *ssl, const unsigned char *cookie,
                                       size_t cookie_len)
  {
      return verify_cookie_callback(ssl, cookie, cookie_len);
  }
  
  #endif
  
  /*
   * Example of extended certificate handling. Where the standard support of
   * one certificate per algorithm is not sufficient an application can decide
   * which certificate(s) to use at runtime based on whatever criteria it deems
   * appropriate.
   */
  
  /* Linked list of certificates, keys and chains */
  struct ssl_excert_st {
      int certform;
      const char *certfile;
      int keyform;
      const char *keyfile;
      const char *chainfile;
      X509 *cert;
      EVP_PKEY *key;
      STACK_OF(X509) *chain;
      int build_chain;
      struct ssl_excert_st *next, *prev;
  };
  
  static STRINT_PAIR chain_flags[] = {
      {"Overall Validity", CERT_PKEY_VALID},
      {"Sign with EE key", CERT_PKEY_SIGN},
      {"EE signature", CERT_PKEY_EE_SIGNATURE},
      {"CA signature", CERT_PKEY_CA_SIGNATURE},
      {"EE key parameters", CERT_PKEY_EE_PARAM},
      {"CA key parameters", CERT_PKEY_CA_PARAM},
      {"Explicitly sign with EE key", CERT_PKEY_EXPLICIT_SIGN},
      {"Issuer Name", CERT_PKEY_ISSUER_NAME},
      {"Certificate Type", CERT_PKEY_CERT_TYPE},
      {NULL}
  };
  
  static void print_chain_flags(SSL *s, int flags)
  {
      STRINT_PAIR *pp;
  
      for (pp = chain_flags; pp->name; ++pp)
          BIO_printf(bio_err, "\t%s: %s\n",
                     pp->name,
                     (flags & pp->retval) ? "OK" : "NOT OK");
      BIO_printf(bio_err, "\tSuite B: ");
      if (SSL_set_cert_flags(s, 0) & SSL_CERT_FLAG_SUITEB_128_LOS)
          BIO_puts(bio_err, flags & CERT_PKEY_SUITEB ? "OK\n" : "NOT OK\n");
      else
          BIO_printf(bio_err, "not tested\n");
  }
  
  /*
   * Very basic selection callback: just use any certificate chain reported as
   * valid. More sophisticated could prioritise according to local policy.
   */
  static int set_cert_cb(SSL *ssl, void *arg)
  {
      int i, rv;
      SSL_EXCERT *exc = arg;
  #ifdef CERT_CB_TEST_RETRY
      static int retry_cnt;
      if (retry_cnt < 5) {
          retry_cnt++;
          BIO_printf(bio_err,
                     "Certificate callback retry test: count %d\n",
                     retry_cnt);
          return -1;
      }
  #endif
      SSL_certs_clear(ssl);
  
      if (exc == NULL)
          return 1;
  
      /*
       * Go to end of list and traverse backwards since we prepend newer
       * entries this retains the original order.
       */
      while (exc->next != NULL)
          exc = exc->next;
  
      i = 0;
  
      while (exc != NULL) {
          i++;
          rv = SSL_check_chain(ssl, exc->cert, exc->key, exc->chain);
          BIO_printf(bio_err, "Checking cert chain %d:\nSubject: ", i);
          X509_NAME_print_ex(bio_err, X509_get_subject_name(exc->cert), 0,
                             get_nameopt());
          BIO_puts(bio_err, "\n");
          print_chain_flags(ssl, rv);
          if (rv & CERT_PKEY_VALID) {
              if (!SSL_use_certificate(ssl, exc->cert)
                      || !SSL_use_PrivateKey(ssl, exc->key)) {
                  return 0;
              }
              /*
               * NB: we wouldn't normally do this as it is not efficient
               * building chains on each connection better to cache the chain
               * in advance.
               */
              if (exc->build_chain) {
                  if (!SSL_build_cert_chain(ssl, 0))
                      return 0;
              } else if (exc->chain != NULL) {
                  SSL_set1_chain(ssl, exc->chain);
              }
          }
          exc = exc->prev;
      }
      return 1;
  }
  
  void ssl_ctx_set_excert(SSL_CTX *ctx, SSL_EXCERT *exc)
  {
      SSL_CTX_set_cert_cb(ctx, set_cert_cb, exc);
  }
  
  static int ssl_excert_prepend(SSL_EXCERT **pexc)
  {
      SSL_EXCERT *exc = app_malloc(sizeof(*exc), "prepend cert");
  
      memset(exc, 0, sizeof(*exc));
  
      exc->next = *pexc;
      *pexc = exc;
  
      if (exc->next) {
          exc->certform = exc->next->certform;
          exc->keyform = exc->next->keyform;
          exc->next->prev = exc;
      } else {
          exc->certform = FORMAT_PEM;
          exc->keyform = FORMAT_PEM;
      }
      return 1;
  
  }
  
  void ssl_excert_free(SSL_EXCERT *exc)
  {
      SSL_EXCERT *curr;
  
      if (exc == NULL)
          return;
      while (exc) {
          X509_free(exc->cert);
          EVP_PKEY_free(exc->key);
          sk_X509_pop_free(exc->chain, X509_free);
          curr = exc;
          exc = exc->next;
          OPENSSL_free(curr);
      }
  }
  
  int load_excert(SSL_EXCERT **pexc)
  {
      SSL_EXCERT *exc = *pexc;
      if (exc == NULL)
          return 1;
      /* If nothing in list, free and set to NULL */
      if (exc->certfile == NULL && exc->next == NULL) {
          ssl_excert_free(exc);
          *pexc = NULL;
          return 1;
      }
      for (; exc; exc = exc->next) {
          if (exc->certfile == NULL) {
              BIO_printf(bio_err, "Missing filename\n");
              return 0;
          }
          exc->cert = load_cert(exc->certfile, exc->certform,
                                "Server Certificate");
          if (exc->cert == NULL)
              return 0;
          if (exc->keyfile != NULL) {
              exc->key = load_key(exc->keyfile, exc->keyform,
                                  0, NULL, NULL, "Server Key");
          } else {
              exc->key = load_key(exc->certfile, exc->certform,
                                  0, NULL, NULL, "Server Key");
          }
          if (exc->key == NULL)
              return 0;
          if (exc->chainfile != NULL) {
              if (!load_certs(exc->chainfile, &exc->chain, FORMAT_PEM, NULL,
                              "Server Chain"))
                  return 0;
          }
      }
      return 1;
  }
  
  enum range { OPT_X_ENUM };
  
  int args_excert(int opt, SSL_EXCERT **pexc)
  {
      SSL_EXCERT *exc = *pexc;
  
      assert(opt > OPT_X__FIRST);
      assert(opt < OPT_X__LAST);
  
      if (exc == NULL) {
          if (!ssl_excert_prepend(&exc)) {
              BIO_printf(bio_err, " %s: Error initialising xcert\n",
                         opt_getprog());
              goto err;
          }
          *pexc = exc;
      }
  
      switch ((enum range)opt) {
      case OPT_X__FIRST:
      case OPT_X__LAST:
          return 0;
      case OPT_X_CERT:
          if (exc->certfile != NULL && !ssl_excert_prepend(&exc)) {
              BIO_printf(bio_err, "%s: Error adding xcert\n", opt_getprog());
              goto err;
          }
          *pexc = exc;
          exc->certfile = opt_arg();
          break;
      case OPT_X_KEY:
          if (exc->keyfile != NULL) {
              BIO_printf(bio_err, "%s: Key already specified\n", opt_getprog());
              goto err;
          }
          exc->keyfile = opt_arg();
          break;
      case OPT_X_CHAIN:
          if (exc->chainfile != NULL) {
              BIO_printf(bio_err, "%s: Chain already specified\n",
                         opt_getprog());
              goto err;
          }
          exc->chainfile = opt_arg();
          break;
      case OPT_X_CHAIN_BUILD:
          exc->build_chain = 1;
          break;
      case OPT_X_CERTFORM:
          if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &exc->certform))
              return 0;
          break;
      case OPT_X_KEYFORM:
          if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &exc->keyform))
              return 0;
          break;
      }
      return 1;
  
   err:
      ERR_print_errors(bio_err);
      ssl_excert_free(exc);
      *pexc = NULL;
      return 0;
  }
  
  static void print_raw_cipherlist(SSL *s)
  {
      const unsigned char *rlist;
      static const unsigned char scsv_id[] = { 0, 0xFF };
      size_t i, rlistlen, num;
      if (!SSL_is_server(s))
          return;
      num = SSL_get0_raw_cipherlist(s, NULL);
      OPENSSL_assert(num == 2);
      rlistlen = SSL_get0_raw_cipherlist(s, &rlist);
      BIO_puts(bio_err, "Client cipher list: ");
      for (i = 0; i < rlistlen; i += num, rlist += num) {
          const SSL_CIPHER *c = SSL_CIPHER_find(s, rlist);
          if (i)
              BIO_puts(bio_err, ":");
          if (c != NULL) {
              BIO_puts(bio_err, SSL_CIPHER_get_name(c));
          } else if (memcmp(rlist, scsv_id, num) == 0) {
              BIO_puts(bio_err, "SCSV");
          } else {
              size_t j;
              BIO_puts(bio_err, "0x");
              for (j = 0; j < num; j++)
                  BIO_printf(bio_err, "%02X", rlist[j]);
          }
      }
      BIO_puts(bio_err, "\n");
  }
  
  /*
   * Hex encoder for TLSA RRdata, not ':' delimited.
   */
  static char *hexencode(const unsigned char *data, size_t len)
  {
      static const char *hex = "0123456789abcdef";
      char *out;
      char *cp;
      size_t outlen = 2 * len + 1;
      int ilen = (int) outlen;
  
      if (outlen < len || ilen < 0 || outlen != (size_t)ilen) {
          BIO_printf(bio_err, "%s: %zu-byte buffer too large to hexencode\n",
                     opt_getprog(), len);
          exit(1);
      }
      cp = out = app_malloc(ilen, "TLSA hex data buffer");
  
      while (len-- > 0) {
          *cp++ = hex[(*data >> 4) & 0x0f];
          *cp++ = hex[*data++ & 0x0f];
      }
      *cp = '\0';
      return out;
  }
  
  void print_verify_detail(SSL *s, BIO *bio)
  {
      int mdpth;
      EVP_PKEY *mspki;
      long verify_err = SSL_get_verify_result(s);
  
      if (verify_err == X509_V_OK) {
          const char *peername = SSL_get0_peername(s);
  
          BIO_printf(bio, "Verification: OK\n");
          if (peername != NULL)
              BIO_printf(bio, "Verified peername: %s\n", peername);
      } else {
          const char *reason = X509_verify_cert_error_string(verify_err);
  
          BIO_printf(bio, "Verification error: %s\n", reason);
      }
  
      if ((mdpth = SSL_get0_dane_authority(s, NULL, &mspki)) >= 0) {
          uint8_t usage, selector, mtype;
          const unsigned char *data = NULL;
          size_t dlen = 0;
          char *hexdata;
  
          mdpth = SSL_get0_dane_tlsa(s, &usage, &selector, &mtype, &data, &dlen);
  
          /*
           * The TLSA data field can be quite long when it is a certificate,
           * public key or even a SHA2-512 digest.  Because the initial octets of
           * ASN.1 certificates and public keys contain mostly boilerplate OIDs
           * and lengths, we show the last 12 bytes of the data instead, as these
           * are more likely to distinguish distinct TLSA records.
           */
  #define TLSA_TAIL_SIZE 12
          if (dlen > TLSA_TAIL_SIZE)
              hexdata = hexencode(data + dlen - TLSA_TAIL_SIZE, TLSA_TAIL_SIZE);
          else
              hexdata = hexencode(data, dlen);
          BIO_printf(bio, "DANE TLSA %d %d %d %s%s %s at depth %d\n",
                     usage, selector, mtype,
                     (dlen > TLSA_TAIL_SIZE) ? "..." : "", hexdata,
                     (mspki != NULL) ? "signed the certificate" :
                     mdpth ? "matched TA certificate" : "matched EE certificate",
                     mdpth);
          OPENSSL_free(hexdata);
      }
  }
  
  void print_ssl_summary(SSL *s)
  {
      const SSL_CIPHER *c;
      X509 *peer;
  
      BIO_printf(bio_err, "Protocol version: %s\n", SSL_get_version(s));
      print_raw_cipherlist(s);
      c = SSL_get_current_cipher(s);
      BIO_printf(bio_err, "Ciphersuite: %s\n", SSL_CIPHER_get_name(c));
      do_print_sigalgs(bio_err, s, 0);
      peer = SSL_get_peer_certificate(s);
      if (peer != NULL) {
          int nid;
  
          BIO_puts(bio_err, "Peer certificate: ");
          X509_NAME_print_ex(bio_err, X509_get_subject_name(peer),
                             0, get_nameopt());
          BIO_puts(bio_err, "\n");
          if (SSL_get_peer_signature_nid(s, &nid))
              BIO_printf(bio_err, "Hash used: %s\n", OBJ_nid2sn(nid));
          if (SSL_get_peer_signature_type_nid(s, &nid))
              BIO_printf(bio_err, "Signature type: %s\n", get_sigtype(nid));
          print_verify_detail(s, bio_err);
      } else {
          BIO_puts(bio_err, "No peer certificate\n");
      }
      X509_free(peer);
  #ifndef OPENSSL_NO_EC
      ssl_print_point_formats(bio_err, s);
      if (SSL_is_server(s))
          ssl_print_groups(bio_err, s, 1);
      else
          ssl_print_tmp_key(bio_err, s);
  #else
      if (!SSL_is_server(s))
          ssl_print_tmp_key(bio_err, s);
  #endif
  }
  
  int config_ctx(SSL_CONF_CTX *cctx, STACK_OF(OPENSSL_STRING) *str,
                 SSL_CTX *ctx)
  {
      int i;
  
      SSL_CONF_CTX_set_ssl_ctx(cctx, ctx);
      for (i = 0; i < sk_OPENSSL_STRING_num(str); i += 2) {
          const char *flag = sk_OPENSSL_STRING_value(str, i);
          const char *arg = sk_OPENSSL_STRING_value(str, i + 1);
          if (SSL_CONF_cmd(cctx, flag, arg) <= 0) {
              if (arg != NULL)
                  BIO_printf(bio_err, "Error with command: \"%s %s\"\n",
                             flag, arg);
              else
                  BIO_printf(bio_err, "Error with command: \"%s\"\n", flag);
              ERR_print_errors(bio_err);
              return 0;
          }
      }
      if (!SSL_CONF_CTX_finish(cctx)) {
          BIO_puts(bio_err, "Error finishing context\n");
          ERR_print_errors(bio_err);
          return 0;
      }
      return 1;
  }
  
  static int add_crls_store(X509_STORE *st, STACK_OF(X509_CRL) *crls)
  {
      X509_CRL *crl;
      int i;
      for (i = 0; i < sk_X509_CRL_num(crls); i++) {
          crl = sk_X509_CRL_value(crls, i);
          X509_STORE_add_crl(st, crl);
      }
      return 1;
  }
  
  int ssl_ctx_add_crls(SSL_CTX *ctx, STACK_OF(X509_CRL) *crls, int crl_download)
  {
      X509_STORE *st;
      st = SSL_CTX_get_cert_store(ctx);
      add_crls_store(st, crls);
      if (crl_download)
          store_setup_crl_download(st);
      return 1;
  }
  
  int ssl_load_stores(SSL_CTX *ctx,
                      const char *vfyCApath, const char *vfyCAfile,
                      const char *chCApath, const char *chCAfile,
                      STACK_OF(X509_CRL) *crls, int crl_download)
  {
      X509_STORE *vfy = NULL, *ch = NULL;
      int rv = 0;
      if (vfyCApath != NULL || vfyCAfile != NULL) {
          vfy = X509_STORE_new();
          if (vfy == NULL)
              goto err;
          if (!X509_STORE_load_locations(vfy, vfyCAfile, vfyCApath))
              goto err;
          add_crls_store(vfy, crls);
          SSL_CTX_set1_verify_cert_store(ctx, vfy);
          if (crl_download)
              store_setup_crl_download(vfy);
      }
      if (chCApath != NULL || chCAfile != NULL) {
          ch = X509_STORE_new();
          if (ch == NULL)
              goto err;
          if (!X509_STORE_load_locations(ch, chCAfile, chCApath))
              goto err;
          SSL_CTX_set1_chain_cert_store(ctx, ch);
      }
      rv = 1;
   err:
      X509_STORE_free(vfy);
      X509_STORE_free(ch);
      return rv;
  }
  
  /* Verbose print out of security callback */
  
  typedef struct {
      BIO *out;
      int verbose;
      int (*old_cb) (const SSL *s, const SSL_CTX *ctx, int op, int bits, int nid,
                     void *other, void *ex);
  } security_debug_ex;
  
  static STRINT_PAIR callback_types[] = {
      {"Supported Ciphersuite", SSL_SECOP_CIPHER_SUPPORTED},
      {"Shared Ciphersuite", SSL_SECOP_CIPHER_SHARED},
      {"Check Ciphersuite", SSL_SECOP_CIPHER_CHECK},
  #ifndef OPENSSL_NO_DH
      {"Temp DH key bits", SSL_SECOP_TMP_DH},
  #endif
      {"Supported Curve", SSL_SECOP_CURVE_SUPPORTED},
      {"Shared Curve", SSL_SECOP_CURVE_SHARED},
      {"Check Curve", SSL_SECOP_CURVE_CHECK},
      {"Supported Signature Algorithm", SSL_SECOP_SIGALG_SUPPORTED},
      {"Shared Signature Algorithm", SSL_SECOP_SIGALG_SHARED},
      {"Check Signature Algorithm", SSL_SECOP_SIGALG_CHECK},
      {"Signature Algorithm mask", SSL_SECOP_SIGALG_MASK},
      {"Certificate chain EE key", SSL_SECOP_EE_KEY},
      {"Certificate chain CA key", SSL_SECOP_CA_KEY},
      {"Peer Chain EE key", SSL_SECOP_PEER_EE_KEY},
      {"Peer Chain CA key", SSL_SECOP_PEER_CA_KEY},
      {"Certificate chain CA digest", SSL_SECOP_CA_MD},
      {"Peer chain CA digest", SSL_SECOP_PEER_CA_MD},
      {"SSL compression", SSL_SECOP_COMPRESSION},
      {"Session ticket", SSL_SECOP_TICKET},
      {NULL}
  };
  
  static int security_callback_debug(const SSL *s, const SSL_CTX *ctx,
                                     int op, int bits, int nid,
                                     void *other, void *ex)
  {
      security_debug_ex *sdb = ex;
      int rv, show_bits = 1, cert_md = 0;
      const char *nm;
      int show_nm;
      rv = sdb->old_cb(s, ctx, op, bits, nid, other, ex);
      if (rv == 1 && sdb->verbose < 2)
          return 1;
      BIO_puts(sdb->out, "Security callback: ");
  
      nm = lookup(op, callback_types, NULL);
      show_nm = nm != NULL;
      switch (op) {
      case SSL_SECOP_TICKET:
      case SSL_SECOP_COMPRESSION:
          show_bits = 0;
          show_nm = 0;
          break;
      case SSL_SECOP_VERSION:
          BIO_printf(sdb->out, "Version=%s", lookup(nid, ssl_versions, "???"));
          show_bits = 0;
          show_nm = 0;
          break;
      case SSL_SECOP_CA_MD:
      case SSL_SECOP_PEER_CA_MD:
          cert_md = 1;
          break;
      case SSL_SECOP_SIGALG_SUPPORTED:
      case SSL_SECOP_SIGALG_SHARED:
      case SSL_SECOP_SIGALG_CHECK:
      case SSL_SECOP_SIGALG_MASK:
          show_nm = 0;
          break;
      }
      if (show_nm)
          BIO_printf(sdb->out, "%s=", nm);
  
      switch (op & SSL_SECOP_OTHER_TYPE) {
  
      case SSL_SECOP_OTHER_CIPHER:
          BIO_puts(sdb->out, SSL_CIPHER_get_name(other));
          break;
  
  #ifndef OPENSSL_NO_EC
      case SSL_SECOP_OTHER_CURVE:
          {
              const char *cname;
              cname = EC_curve_nid2nist(nid);
              if (cname == NULL)
                  cname = OBJ_nid2sn(nid);
              BIO_puts(sdb->out, cname);
          }
          break;
  #endif
  #ifndef OPENSSL_NO_DH
      case SSL_SECOP_OTHER_DH:
          {
              DH *dh = other;
              BIO_printf(sdb->out, "%d", DH_bits(dh));
              break;
          }
  #endif
      case SSL_SECOP_OTHER_CERT:
          {
              if (cert_md) {
                  int sig_nid = X509_get_signature_nid(other);
                  BIO_puts(sdb->out, OBJ_nid2sn(sig_nid));
              } else {
                  EVP_PKEY *pkey = X509_get0_pubkey(other);
                  const char *algname = "";
                  EVP_PKEY_asn1_get0_info(NULL, NULL, NULL, NULL,
                                          &algname, EVP_PKEY_get0_asn1(pkey));
                  BIO_printf(sdb->out, "%s, bits=%d",
                             algname, EVP_PKEY_bits(pkey));
              }
              break;
          }
      case SSL_SECOP_OTHER_SIGALG:
          {
              const unsigned char *salg = other;
              const char *sname = NULL;
              int raw_sig_code = (salg[0] << 8) + salg[1]; /* always big endian (msb, lsb) */
                  /* raw_sig_code: signature_scheme from tls1.3, or signature_and_hash from tls1.2 */
  
              if (nm != NULL)
                  BIO_printf(sdb->out, "%s", nm);
              else
                  BIO_printf(sdb->out, "s_cb.c:security_callback_debug op=0x%x", op);
  
              sname = lookup(raw_sig_code, signature_tls13_scheme_list, NULL);
              if (sname != NULL) {
                  BIO_printf(sdb->out, " scheme=%s", sname);
              } else {
                  int alg_code = salg[1];
                  int hash_code = salg[0];
                  const char *alg_str = lookup(alg_code, signature_tls12_alg_list, NULL);
                  const char *hash_str = lookup(hash_code, signature_tls12_hash_list, NULL);
  
                  if (alg_str != NULL && hash_str != NULL)
                      BIO_printf(sdb->out, " digest=%s, algorithm=%s", hash_str, alg_str);
                  else
                      BIO_printf(sdb->out, " scheme=unknown(0x%04x)", raw_sig_code);
              }
          }
  
      }
  
      if (show_bits)
          BIO_printf(sdb->out, ", security bits=%d", bits);
      BIO_printf(sdb->out, ": %s\n", rv ? "yes" : "no");
      return rv;
  }
  
  void ssl_ctx_security_debug(SSL_CTX *ctx, int verbose)
  {
      static security_debug_ex sdb;
  
      sdb.out = bio_err;
      sdb.verbose = verbose;
      sdb.old_cb = SSL_CTX_get_security_callback(ctx);
      SSL_CTX_set_security_callback(ctx, security_callback_debug);
      SSL_CTX_set0_security_ex_data(ctx, &sdb);
  }
  
  static void keylog_callback(const SSL *ssl, const char *line)
  {
      if (bio_keylog == NULL) {
          BIO_printf(bio_err, "Keylog callback is invoked without valid file!\n");
          return;
      }
  
      /*
       * There might be concurrent writers to the keylog file, so we must ensure
       * that the given line is written at once.
       */
      BIO_printf(bio_keylog, "%s\n", line);
      (void)BIO_flush(bio_keylog);
  }
  
  int set_keylog_file(SSL_CTX *ctx, const char *keylog_file)
  {
      /* Close any open files */
      BIO_free_all(bio_keylog);
      bio_keylog = NULL;
  
      if (ctx == NULL || keylog_file == NULL) {
          /* Keylogging is disabled, OK. */
          return 0;
      }
  
      /*
       * Append rather than write in order to allow concurrent modification.
       * Furthermore, this preserves existing keylog files which is useful when
       * the tool is run multiple times.
       */
      bio_keylog = BIO_new_file(keylog_file, "a");
      if (bio_keylog == NULL) {
          BIO_printf(bio_err, "Error writing keylog file %s\n", keylog_file);
          return 1;
      }
  
      /* Write a header for seekable, empty files (this excludes pipes). */
      if (BIO_tell(bio_keylog) == 0) {
          BIO_puts(bio_keylog,
                   "# SSL/TLS secrets log file, generated by OpenSSL\n");
          (void)BIO_flush(bio_keylog);
      }
      SSL_CTX_set_keylog_callback(ctx, keylog_callback);
      return 0;
  }
  
  void print_ca_names(BIO *bio, SSL *s)
  {
      const char *cs = SSL_is_server(s) ? "server" : "client";
      const STACK_OF(X509_NAME) *sk = SSL_get0_peer_CA_list(s);
      int i;
  
      if (sk == NULL || sk_X509_NAME_num(sk) == 0) {
          BIO_printf(bio, "---\nNo %s certificate CA names sent\n", cs);
          return;
      }
  
      BIO_printf(bio, "---\nAcceptable %s certificate CA names\n",cs);
      for (i = 0; i < sk_X509_NAME_num(sk); i++) {
          X509_NAME_print_ex(bio, sk_X509_NAME_value(sk, i), 0, get_nameopt());
          BIO_write(bio, "\n", 1);
      }
  }
  