/************************************************************************************
  Copyright (C) 2014 MariaDB Corporation AB

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Library General Public
  License as published by the Free Software Foundation; either
  version 2 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Library General Public License for more details.

  You should have received a copy of the GNU Library General Public
  License along with this library; if not see <http://www.gnu.org/licenses>
  or write to the Free Software Foundation, Inc.,
  51 Franklin St., Fifth Floor, Boston, MA 02110, USA

 *************************************************************************************/
#ifdef HAVE_GNUTLS

#include <ma_global.h>
#include <gnutls/gnutls.h>
#include <gnutls/x509.h>
#include <gnutls/abstract.h>
#include <ma_sys.h>
#include <ma_common.h>
#include <ma_pvio.h>
#include <errmsg.h>
#include <ma_pthread.h>
#include <mysql/client_plugin.h>
#include <string.h>
#include <ma_tls.h>
#include <mariadb_async.h>
#include <ma_context.h>

pthread_mutex_t LOCK_gnutls_config;

extern my_bool ma_tls_initialized;
extern unsigned int mariadb_deinitialize_ssl;

enum ma_pem_type {
  MA_TLS_PEM_CERT= 0,
  MA_TLS_PEM_KEY,
  MA_TLS_PEM_CA,
  MA_TLS_PEM_CRL
};

static int my_verify_callback(gnutls_session_t ssl);

char tls_library_version[TLS_VERSION_LENGTH];

struct st_cipher_map {
  unsigned char sid[2];
  const char *iana_name;
  const char *openssl_name;
  const char *gnutls_name;
};

const struct st_cipher_map tls_ciphers[]=
{
  { {0x00, 0x01},
    "TLS_RSA_WITH_NULL_MD5",
     NULL,
    "TLS_RSA_NULL_MD5"},
  { {0x00, 0x02},
    "TLS_RSA_WITH_NULL_SHA",
     NULL,
    "TLS_RSA_NULL_SHA1"},
  { {0x00, 0x3B},
    "TLS_RSA_WITH_NULL_SHA256",
     NULL,
    "TLS_RSA_NULL_SHA256"},
  { {0x00, 0x05},
    "TLS_RSA_WITH_RC4_128_SHA",
     NULL,
    "TLS_RSA_ARCFOUR_128_SHA1"},
  { {0x00, 0x04},
    "TLS_RSA_WITH_RC4_128_MD5",
     NULL,
    "TLS_RSA_ARCFOUR_128_MD5"},
  { {0x00, 0x0A},
    "TLS_RSA_WITH_3DES_EDE_CBC_SHA",
    "DES-CBC3-SHA",
    "TLS_RSA_3DES_EDE_CBC_SHA1"},
  { {0x00, 0x2F},
    "TLS_RSA_WITH_AES_128_CBC_SHA",
    "AES128-SHA",
    "TLS_RSA_AES_128_CBC_SHA1"},
  { {0x00, 0x35},
    "TLS_RSA_WITH_AES_256_CBC_SHA",
    "AES256-SHA",
    "TLS_RSA_AES_256_CBC_SHA1"},
  { {0x00, 0xBA},
    "TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256",
    "CAMELLIA128-SHA256",
    "TLS_RSA_CAMELLIA_128_CBC_SHA256"},
  { {0x00, 0xC0},
    "TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256",
     NULL,
    "TLS_RSA_CAMELLIA_256_CBC_SHA256"},
  { {0x00, 0x41},
    "TLS_RSA_WITH_CAMELLIA_128_CBC_SHA",
    "CAMELLIA128-SHA",
    "TLS_RSA_CAMELLIA_128_CBC_SHA1"},
  { {0x00, 0x84},
    "TLS_RSA_WITH_CAMELLIA_256_CBC_SHA",
    "CAMELLIA256-SHA",
    "TLS_RSA_CAMELLIA_256_CBC_SHA1"},
  { {0x00, 0x3C},
    "TLS_RSA_WITH_AES_128_CBC_SHA256",
    "AES128-SHA256",
    "TLS_RSA_AES_128_CBC_SHA256"},
  { {0x00, 0x3D},
    "TLS_RSA_WITH_AES_256_CBC_SHA256",
    "AES256-SHA256",
    "TLS_RSA_AES_256_CBC_SHA256"},
  { {0x00, 0x9C},
    "TLS_RSA_WITH_AES_128_GCM_SHA256",
    "AES128-GCM-SHA256",
    "TLS_RSA_AES_128_GCM_SHA256"},
  { {0x00, 0x9D},
    "TLS_RSA_WITH_AES_256_GCM_SHA384",
    "AES256-GCM-SHA384",
    "TLS_RSA_AES_256_GCM_SHA384"},
  { {0xC0, 0x7A},
    "TLS_RSA_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_RSA_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x7B},
    "TLS_RSA_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_RSA_CAMELLIA_256_GCM_SHA384"},
  { {0xC0, 0x9C},
    "TLS_RSA_WITH_AES_128_CCM",
     NULL,
    "TLS_RSA_AES_128_CCM"},
  { {0xC0, 0x9D},
    "TLS_RSA_WITH_AES_256_CCM",
     NULL,
    "TLS_RSA_AES_256_CCM"},
  { {0xC0, 0xA0},
    "TLS_RSA_WITH_AES_128_CCM_8",
     NULL,
    "TLS_RSA_AES_128_CCM_8"},
  { {0xC0, 0xA1},
    "TLS_RSA_WITH_AES_256_CCM_8",
     NULL,
    "TLS_RSA_AES_256_CCM_8"},
  { {0x00, 0x66},
    "TLS_DHE_DSS_WITH_RC4_128_SHA",
    NULL,
    "TLS_DHE_DSS_ARCFOUR_128_SHA1"},
  { {0x00, 0x13},
    "TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA",
     NULL,
    "TLS_DHE_DSS_3DES_EDE_CBC_SHA1"},
  { {0x00, 0x32},
    "TLS_DHE_DSS_WITH_AES_128_CBC_SHA",
     NULL,
    "TLS_DHE_DSS_AES_128_CBC_SHA1"},
  { {0x00, 0x38},
    "TLS_DHE_DSS_WITH_AES_256_CBC_SHA",
     NULL,
    "TLS_DHE_DSS_AES_256_CBC_SHA1"},
  { {0x00, 0xBD},
    "TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_DHE_DSS_CAMELLIA_128_CBC_SHA256"},
  { {0x00, 0xC3},
    "TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256",
     NULL,
    "TLS_DHE_DSS_CAMELLIA_256_CBC_SHA256"},
  { {0x00, 0x44},
    "TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA",
     NULL,
    "TLS_DHE_DSS_CAMELLIA_128_CBC_SHA1"},
  { {0x00, 0x87},
    "TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA",
     NULL,
    "TLS_DHE_DSS_CAMELLIA_256_CBC_SHA1"},
  { {0x00, 0x40},
    "TLS_DHE_DSS_WITH_AES_128_CBC_SHA256",
     NULL,
    "TLS_DHE_DSS_AES_128_CBC_SHA256"},
  { {0x00, 0x6A},
    "TLS_DHE_DSS_WITH_AES_256_CBC_SHA256",
     NULL,
    "TLS_DHE_DSS_AES_256_CBC_SHA256"},
  { {0x00, 0xA2},
    "TLS_DHE_DSS_WITH_AES_128_GCM_SHA256",
     NULL,
    "TLS_DHE_DSS_AES_128_GCM_SHA256"},
  { {0x00, 0xA3},
    "TLS_DHE_DSS_WITH_AES_256_GCM_SHA384",
     NULL,
    "TLS_DHE_DSS_AES_256_GCM_SHA384"},
  { {0xC0, 0x80},
    "TLS_DHE_DSS_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_DHE_DSS_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x81},
    "TLS_DHE_DSS_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_DHE_DSS_CAMELLIA_256_GCM_SHA384"},
  { {0x00, 0x16},
    "TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA",
    "EDH-RSA-DES-CBC3-SHA",
    "TLS_DHE_RSA_3DES_EDE_CBC_SHA1"},
  { {0x00, 0x33},
    "TLS_DHE_RSA_WITH_AES_128_CBC_SHA",
    "DHE-RSA-AES128-SHA",
    "TLS_DHE_RSA_AES_128_CBC_SHA1"},
  { {0x00, 0x39},
    "TLS_DHE_RSA_WITH_AES_256_CBC_SHA",
    "DHE-RSA-AES256-SHA",
    "TLS_DHE_RSA_AES_256_CBC_SHA1"},
  { {0x00, 0xBE},
    "TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_DHE_RSA_CAMELLIA_128_CBC_SHA256"},
  { {0x00, 0xC4},
    "TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256",
     NULL,
    "TLS_DHE_RSA_CAMELLIA_256_CBC_SHA256"},
  { {0x00, 0x45},
    "TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA",
    "DHE-RSA-CAMELLIA128-SHA",
    "TLS_DHE_RSA_CAMELLIA_128_CBC_SHA1"},
  { {0x00, 0x88},
    "TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA",
    "DHE-RSA-CAMELLIA256-SHA",
    "TLS_DHE_RSA_CAMELLIA_256_CBC_SHA1"},
  { {0x00, 0x67},
    "TLS_DHE_RSA_WITH_AES_128_CBC_SHA256",
    "DHE-RSA-AES128-SHA256",
    "TLS_DHE_RSA_AES_128_CBC_SHA256"},
  { {0x00, 0x6B},
    "TLS_DHE_RSA_WITH_AES_256_CBC_SHA256",
    "DHE-RSA-AES256-SHA256",
    "TLS_DHE_RSA_AES_256_CBC_SHA256"},
  { {0x00, 0x9E},
    "TLS_DHE_RSA_WITH_AES_128_GCM_SHA256",
    "DHE-RSA-AES128-GCM-SHA256",
    "TLS_DHE_RSA_AES_128_GCM_SHA256"},
  { {0x00, 0x9F},
    "TLS_DHE_RSA_WITH_AES_256_GCM_SHA384",
    "DHE-RSA-AES256-GCM-SHA384",
    "TLS_DHE_RSA_AES_256_GCM_SHA384"},
  { {0xC0, 0x7C},
    "TLS_DHE_RSA_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_DHE_RSA_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x7D},
    "TLS_DHE_RSA_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_DHE_RSA_CAMELLIA_256_GCM_SHA384"},
  { {0xCC, 0xAA},
    "TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256",
    "DHE-RSA-CHACHA20-POLY1305",
    "TLS_DHE_RSA_CHACHA20_POLY1305"},
  { {0xC0, 0x9E},
    "TLS_DHE_RSA_WITH_AES_128_CCM",
     NULL,
    "TLS_DHE_RSA_AES_128_CCM"},
  { {0xC0, 0x9F},
    "TLS_DHE_RSA_WITH_AES_256_CCM",
     NULL,
    "TLS_DHE_RSA_AES_256_CCM"},
  { {0xC0, 0xA2},
    "TLS_DHE_RSA_WITH_AES_128_CCM_8",
     NULL,
    "TLS_DHE_RSA_AES_128_CCM_8"},
  { {0xC0, 0xA3},
    "TLS_DHE_RSA_WITH_AES_256_CCM_8",
     NULL,
    "TLS_DHE_RSA_AES_256_CCM_8"},
  { {0xC0, 0x10},
    "TLS_ECDHE_RSA_WITH_",
     NULL,
    "TLS_ECDHE_RSA_NULL_SHA1"},
  { {0xC0, 0x12},
    "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA",
    "ECDHE-RSA-DES-CBC3-SHA",
    "TLS_ECDHE_RSA_3DES_EDE_CBC_SHA1"},
  { {0xC0, 0x13},
    "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA",
    "ECDHE-RSA-AES128-SHA",
    "TLS_ECDHE_RSA_AES_128_CBC_SHA1"},
  { {0xC0, 0x14},
    "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA",
    "ECDHE-RSA-AES256-SHA",
    "TLS_ECDHE_RSA_AES_256_CBC_SHA1"},
  { {0xC0, 0x28},
    "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384",
    "ECDHE-RSA-AES256-SHA384",
    "TLS_ECDHE_RSA_AES_256_CBC_SHA384"},
  { {0xC0, 0x11},
    "TLS_ECDHE_RSA_WITH_RC4_128_SHA",
     NULL,
    "TLS_ECDHE_RSA_ARCFOUR_128_SHA1"},
  { {0xC0, 0x76},
    "TLS_ECDHE_RSA_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_ECDHE_RSA_CAMELLIA_128_CBC_SHA256"},
  { {0xC0, 0x77},
    "TLS_ECDHE_RSA_WITH_CAMELLIA_256_CBC_SHA384",
     NULL,
    "TLS_ECDHE_RSA_CAMELLIA_256_CBC_SHA384"},
  { {0xC0, 0x06},
    "TLS_ECDHE_ECDSA_WITH_",
     NULL,
    "TLS_ECDHE_ECDSA_NULL_SHA1"},
  { {0xC0, 0x08},
    "TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA",
    "ECDHE-ECDSA-DES-CBC3-SHA",
    "TLS_ECDHE_ECDSA_3DES_EDE_CBC_SHA1"},
  { {0xC0, 0x09},
    "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA",
    "ECDHE-ECDSA-AES128-SHA",
    "TLS_ECDHE_ECDSA_AES_128_CBC_SHA1"},
  { {0xC0, 0x0A},
    "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA",
    "ECDHE-ECDSA-AES256-SHA",
    "TLS_ECDHE_ECDSA_AES_256_CBC_SHA1"},
  { {0xC0, 0x07},
    "TLS_ECDHE_ECDSA_WITH_RC4_128_SHA",
     NULL,
    "TLS_ECDHE_ECDSA_ARCFOUR_128_SHA1"},
  { {0xC0, 0x72},
    "TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_ECDHE_ECDSA_CAMELLIA_128_CBC_SHA256"},
  { {0xC0, 0x73},
    "TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_CBC_SHA384",
     NULL,
    "TLS_ECDHE_ECDSA_CAMELLIA_256_CBC_SHA384"},
  { {0xC0, 0x23},
    "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256",
    "ECDHE-ECDSA-AES128-SHA256",
    "TLS_ECDHE_ECDSA_AES_128_CBC_SHA256"},
  { {0xC0, 0x27},
    "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256",
    "ECDHE-RSA-AES128-SHA256",
    "TLS_ECDHE_RSA_AES_128_CBC_SHA256"},
  { {0xC0, 0x86},
    "TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_ECDHE_ECDSA_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x87},
    "TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_ECDHE_ECDSA_CAMELLIA_256_GCM_SHA384"},
  { {0xC0, 0x2B},
    "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
    "ECDHE-ECDSA-AES128-GCM-SHA256",
    "TLS_ECDHE_ECDSA_AES_128_GCM_SHA256"},
  { {0xC0, 0x2C},
    "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
    "ECDHE-ECDSA-AES256-GCM-SHA384",
    "TLS_ECDHE_ECDSA_AES_256_GCM_SHA384"},
  { {0xC0, 0x2F},
    "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
    "ECDHE-RSA-AES128-GCM-SHA256",
    "TLS_ECDHE_RSA_AES_128_GCM_SHA256"},
  { {0xC0, 0x30},
    "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384",
    "ECDHE-RSA-AES256-GCM-SHA384",
    "TLS_ECDHE_RSA_AES_256_GCM_SHA384"},
  { {0xC0, 0x24},
    "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384",
    "ECDHE-ECDSA-AES256-SHA384",
    "TLS_ECDHE_ECDSA_AES_256_CBC_SHA384"},
  { {0xC0, 0x8A},
    "TLS_ECDHE_RSA_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_ECDHE_RSA_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x8B},
    "TLS_ECDHE_RSA_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_ECDHE_RSA_CAMELLIA_256_GCM_SHA384"},
  { {0xCC, 0xA8},
    "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256",
    "ECDHE-RSA-CHACHA20-POLY1305",
    "TLS_ECDHE_RSA_CHACHA20_POLY1305"},
  { {0xCC, 0xA9},
    "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256",
    "ECDHE-ECDSA-CHACHA20-POLY1305",
    "TLS_ECDHE_ECDSA_CHACHA20_POLY1305"},
  { {0xC0, 0xAC},
    "TLS_ECDHE_ECDSA_WITH_AES_128_CCM",
     NULL,
    "TLS_ECDHE_ECDSA_AES_128_CCM"},
  { {0xC0, 0xAD},
    "TLS_ECDHE_ECDSA_WITH_AES_256_CCM",
     NULL,
    "TLS_ECDHE_ECDSA_AES_256_CCM"},
  { {0xC0, 0xAE},
    "TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8",
     NULL,
    "TLS_ECDHE_ECDSA_AES_128_CCM_8"},
  { {0xC0, 0xAF},
    "TLS_ECDHE_ECDSA_WITH_AES_256_CCM_8",
     NULL,
    "TLS_ECDHE_ECDSA_AES_256_CCM_8"},
  { {0xC0, 0x34},
    "TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA",
    "ECDHE-PSK-3DES-EDE-CBC-SHA",
    "TLS_ECDHE_PSK_3DES_EDE_CBC_SHA1"},
  { {0xC0, 0x35},
    "TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA",
    "ECDHE-PSK-AES128-CBC-SHA",
    "TLS_ECDHE_PSK_AES_128_CBC_SHA1"},
  { {0xC0, 0x36},
    "TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA",
    "ECDHE-PSK-AES256-CBC-SHA",
    "TLS_ECDHE_PSK_AES_256_CBC_SHA1"},
  { {0xC0, 0x37},
    "TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256",
    "ECDHE-PSK-AES128-CBC-SHA256",
    "TLS_ECDHE_PSK_AES_128_CBC_SHA256"},
  { {0xC0, 0x38},
    "TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384",
    "ECDHE-PSK-AES256-CBC-SHA384",
    "TLS_ECDHE_PSK_AES_256_CBC_SHA384"},
  { {0xC0, 0x33},
    "TLS_ECDHE_PSK_WITH_RC4_128_SHA",
     NULL,
    "TLS_ECDHE_PSK_ARCFOUR_128_SHA1"},
  { {0xC0, 0x39},
    "TLS_ECDHE_PSK_WITH_NULL_SHA",
     NULL,
    "TLS_ECDHE_PSK_NULL_SHA1"},
  { {0xC0, 0x3A},
    "TLS_ECDHE_PSK_WITH_NULL_SHA256",
     NULL,
    "TLS_ECDHE_PSK_NULL_SHA256"},
  { {0xC0, 0x3B},
    "TLS_ECDHE_PSK_WITH_NULL_SHA384",
     NULL,
    "TLS_ECDHE_PSK_NULL_SHA384"},
  { {0xC0, 0x9A},
    "TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_ECDHE_PSK_CAMELLIA_128_CBC_SHA256"},
  { {0xC0, 0x9B},
    "TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384",
     NULL,
    "TLS_ECDHE_PSK_CAMELLIA_256_CBC_SHA384"},
  { {0x00, 0x8A},
    "TLS_PSK_WITH_RC4_128_SHA",
     NULL,
    "TLS_PSK_ARCFOUR_128_SHA1"},
  { {0x00, 0x8B},
    "TLS_PSK_WITH_3DES_EDE_CBC_SHA",
    "PSK-3DES-EDE-CBC-SHA",
    "TLS_PSK_3DES_EDE_CBC_SHA1"},
  { {0x00, 0x8C},
    "TLS_PSK_WITH_AES_128_CBC_SHA",
    "PSK-AES128-CBC-SHA",
    "TLS_PSK_AES_128_CBC_SHA1"},
  { {0x00, 0x8D},
    "TLS_PSK_WITH_AES_256_CBC_SHA",
    "PSK-AES256-CBC-SHA",
    "TLS_PSK_AES_256_CBC_SHA1"},
  { {0x00, 0xAE},
    "TLS_PSK_WITH_AES_128_CBC_SHA256",
    "PSK-AES128-CBC-SHA256",
    "TLS_PSK_AES_128_CBC_SHA256"},
  { {0x00, 0xA9},
    "TLS_PSK_WITH_AES_256_GCM_SHA384",
    "PSK-AES256-GCM-SHA384",
    "TLS_PSK_AES_256_GCM_SHA384"},
  { {0xC0, 0x8E},
    "TLS_PSK_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_PSK_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x8F},
    "TLS_PSK_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_PSK_CAMELLIA_256_GCM_SHA384"},
  { {0x00, 0xA8},
    "TLS_PSK_WITH_AES_128_GCM_SHA256",
    "PSK-AES128-GCM-SHA256",
    "TLS_PSK_AES_128_GCM_SHA256"},
  { {0x00, 0x2C},
    "TLS_PSK_WITH_",
     NULL,
    "TLS_PSK_NULL_SHA1"},
  { {0x00, 0xB0},
    "TLS_PSK_WITH_",
     NULL,
    "TLS_PSK_NULL_SHA256"},
  { {0xC0, 0x94},
    "TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_PSK_CAMELLIA_128_CBC_SHA256"},
  { {0xC0, 0x95},
    "TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384",
     NULL,
    "TLS_PSK_CAMELLIA_256_CBC_SHA384"},
  { {0x00, 0xAF},
    "TLS_PSK_WITH_AES_256_CBC_SHA384",
    "PSK-AES256-CBC-SHA384",
    "TLS_PSK_AES_256_CBC_SHA384"},
  { {0x00, 0xB1},
    "TLS_PSK_WITH_",
     NULL,
    "TLS_PSK_NULL_SHA384"},
  { {0x00, 0x92},
    "TLS_RSA_PSK_WITH_RC4_128_SHA",
     NULL,
    "TLS_RSA_PSK_ARCFOUR_128_SHA1"},
  { {0x00, 0x93},
    "TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA",
    "RSA-PSK-3DES-EDE-CBC-SHA",
    "TLS_RSA_PSK_3DES_EDE_CBC_SHA1"},
  { {0x00, 0x94},
    "TLS_RSA_PSK_WITH_AES_128_CBC_SHA",
    "RSA-PSK-AES128-CBC-SHA",
    "TLS_RSA_PSK_AES_128_CBC_SHA1"},
  { {0x00, 0x95},
    "TLS_RSA_PSK_WITH_AES_256_CBC_SHA",
    "RSA-PSK-AES256-CBC-SHA",
    "TLS_RSA_PSK_AES_256_CBC_SHA1"},
  { {0xC0, 0x92},
    "TLS_RSA_PSK_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_RSA_PSK_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x93},
    "TLS_RSA_PSK_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_RSA_PSK_CAMELLIA_256_GCM_SHA384"},
  { {0x00, 0xAC},
    "TLS_RSA_PSK_WITH_AES_128_GCM_SHA256",
    "RSA-PSK-AES128-GCM-SHA256",
    "TLS_RSA_PSK_AES_128_GCM_SHA256"},
  { {0x00, 0xB6},
    "TLS_RSA_PSK_WITH_AES_128_CBC_SHA256",
    "RSA-PSK-AES128-CBC-SHA256",
    "TLS_RSA_PSK_AES_128_CBC_SHA256"},
  { {0x00, 0x2E},
    "TLS_RSA_PSK_WITH_NULL_SHA",
     NULL,
    "TLS_RSA_PSK_NULL_SHA1"},
  { {0x00, 0xB8},
    "TLS_RSA_PSK_WITH_",
     NULL,
    "TLS_RSA_PSK_NULL_SHA256"},
  { {0x00, 0xAD},
    "TLS_RSA_PSK_WITH_AES_256_GCM_SHA384",
    "RSA-PSK-AES256-GCM-SHA384",
    "TLS_RSA_PSK_AES_256_GCM_SHA384"},
  { {0x00, 0xB7},
    "TLS_RSA_PSK_WITH_AES_256_CBC_SHA384",
    "RSA-PSK-AES256-CBC-SHA384",
    "TLS_RSA_PSK_AES_256_CBC_SHA384"},
  { {0x00, 0xB9},
    "TLS_RSA_PSK_WITH_",
     NULL,
    "TLS_RSA_PSK_NULL_SHA384"},
  { {0xC0, 0x98},
    "TLS_RSA_PSK_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_RSA_PSK_CAMELLIA_128_CBC_SHA256"},
  { {0xC0, 0x99},
    "TLS_RSA_PSK_WITH_CAMELLIA_256_CBC_SHA384",
     NULL,
    "TLS_RSA_PSK_CAMELLIA_256_CBC_SHA384"},
  { {0x00, 0x8E},
    "TLS_DHE_PSK_WITH_RC4_128_SHA",
     NULL,
    "TLS_DHE_PSK_ARCFOUR_128_SHA1"},
  { {0x00, 0x8F},
    "TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA",
    "DHE-PSK-3DES-EDE-CBC-SHA",
    "TLS_DHE_PSK_3DES_EDE_CBC_SHA1"},
  { {0x00, 0x90},
    "TLS_DHE_PSK_WITH_AES_128_CBC_SHA",
    "DHE-PSK-AES128-CBC-SHA",
    "TLS_DHE_PSK_AES_128_CBC_SHA1"},
  { {0x00, 0x91},
    "TLS_DHE_PSK_WITH_AES_256_CBC_SHA",
    "DHE-PSK-AES256-CBC-SHA",
    "TLS_DHE_PSK_AES_256_CBC_SHA1"},
  { {0x00, 0xB2},
    "TLS_DHE_PSK_WITH_AES_128_CBC_SHA256",
    "DHE-PSK-AES128-CBC-SHA256",
    "TLS_DHE_PSK_AES_128_CBC_SHA256"},
  { {0x00, 0xAA},
    "TLS_DHE_PSK_WITH_AES_128_GCM_SHA256",
    "DHE-PSK-AES128-GCM-SHA256",
    "TLS_DHE_PSK_AES_128_GCM_SHA256"},
  { {0x00, 0x2D},
    "TLS_DHE_PSK_WITH_",
     NULL,
    "TLS_DHE_PSK_NULL_SHA1"},
  { {0x00, 0xB4},
    "TLS_DHE_PSK_WITH_",
     NULL,
    "TLS_DHE_PSK_NULL_SHA256"},
  { {0x00, 0xB5},
    "TLS_DHE_PSK_WITH_",
     NULL,
    "TLS_DHE_PSK_NULL_SHA384"},
  { {0x00, 0xB3},
    "TLS_DHE_PSK_WITH_AES_256_CBC_SHA384",
    "DHE-PSK-AES256-CBC-SHA384",
    "TLS_DHE_PSK_AES_256_CBC_SHA384"},
  { {0x00, 0xAB},
    "TLS_DHE_PSK_WITH_AES_256_GCM_SHA384",
    "DHE-PSK-AES256-GCM-SHA384",
    "TLS_DHE_PSK_AES_256_GCM_SHA384"},
  { {0xC0, 0x96},
    "TLS_DHE_PSK_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_DHE_PSK_CAMELLIA_128_CBC_SHA256"},
  { {0xC0, 0x97},
    "TLS_DHE_PSK_WITH_CAMELLIA_256_CBC_SHA384",
     NULL,
    "TLS_DHE_PSK_CAMELLIA_256_CBC_SHA384"},
  { {0xC0, 0x90},
    "TLS_DHE_PSK_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_DHE_PSK_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x91},
    "TLS_DHE_PSK_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_DHE_PSK_CAMELLIA_256_GCM_SHA384"},
  { {0xC0, 0xA4},
    "TLS_PSK_WITH_AES_128_CCM",
     NULL,
    "TLS_PSK_AES_128_CCM"},
  { {0xC0, 0xA5},
    "TLS_PSK_WITH_AES_256_CCM",
     NULL,
    "TLS_PSK_AES_256_CCM"},
  { {0xC0, 0xA6},
    "TLS_DHE_PSK_WITH_AES_128_CCM",
     NULL,
    "TLS_DHE_PSK_AES_128_CCM"},
  { {0xC0, 0xA7},
    "TLS_DHE_PSK_WITH_AES_256_CCM",
     NULL,
    "TLS_DHE_PSK_AES_256_CCM"},
  { {0xC0, 0xA8},
    "TLS_PSK_WITH_AES_128_CCM_8",
     NULL,
    "TLS_PSK_AES_128_CCM_8"},
  { {0xC0, 0xA9},
    "TLS_PSK_WITH_AES_256_CCM_8",
     NULL,
    "TLS_PSK_AES_256_CCM_8"},
  { {0xC0, 0xAA},
    "TLS_PSK_DHE_WITH_AES_128_CCM_8",
     NULL,
    "TLS_DHE_PSK_AES_128_CCM_8"},
  { {0xC0, 0xAB},
    "TLS_PSK_DHE_WITH_AES_256_CCM_8",
     NULL,
    "TLS_DHE_PSK_AES_256_CCM_8"},
  { {0xCC, 0xAD},
    "TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256",
    "DHE-PSK-CHACHA20-POLY1305",
    "TLS_DHE_PSK_CHACHA20_POLY1305"},
  { {0xCC, 0xAC},
    "TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256",
    "ECDHE-PSK-CHACHA20-POLY1305",
    "TLS_ECDHE_PSK_CHACHA20_POLY1305"},
  { {0xCC, 0xAE},
    "TLS_RSA_PSK_WITH_CHACHA20_POLY1305_SHA256",
    "RSA-PSK-CHACHA20-POLY1305",
    "TLS_RSA_PSK_CHACHA20_POLY1305"},
  { {0xCC, 0xAB},
    "TLS_PSK_WITH_CHACHA20_POLY1305_SHA256",
    "PSK-CHACHA20-POLY1305",
    "TLS_PSK_CHACHA20_POLY1305"},
  { {0x00, 0x18},
    "TLS_DH_anon_WITH_RC4_128_MD5",
     NULL,
    "TLS_DH_ANON_ARCFOUR_128_MD5"},
  { {0x00, 0x1B},
    "TLS_DH_anon_WITH_3DES_EDE_CBC_SHA",
     NULL,
    "TLS_DH_ANON_3DES_EDE_CBC_SHA1"},
  { {0x00, 0x34},
    "TLS_DH_anon_WITH_AES_128_CBC_SHA",
     NULL,
    "TLS_DH_ANON_AES_128_CBC_SHA1"},
  { {0x00, 0x3A},
    "TLS_DH_anon_WITH_AES_256_CBC_SHA",
     NULL,
    "TLS_DH_ANON_AES_256_CBC_SHA1"},
  { {0x00, 0xBF},
    "TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA256",
     NULL,
    "TLS_DH_ANON_CAMELLIA_128_CBC_SHA256"},
  { {0x00, 0xC5},
    "TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA256",
     NULL,
    "TLS_DH_ANON_CAMELLIA_256_CBC_SHA256"},
  { {0x00, 0x46},
    "TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA",
     NULL,
    "TLS_DH_ANON_CAMELLIA_128_CBC_SHA1"},
  { {0x00, 0x89},
    "TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA",
     NULL,
    "TLS_DH_ANON_CAMELLIA_256_CBC_SHA1"},
  { {0x00, 0x6C},
    "TLS_DH_anon_WITH_AES_128_CBC_SHA256",
     NULL,
    "TLS_DH_ANON_AES_128_CBC_SHA256"},
  { {0x00, 0x6D},
    "TLS_DH_anon_WITH_AES_256_CBC_SHA256",
     NULL,
    "TLS_DH_ANON_AES_256_CBC_SHA256"},
  { {0x00, 0xA6},
    "TLS_DH_anon_WITH_AES_128_GCM_SHA256",
     NULL,
    "TLS_DH_ANON_AES_128_GCM_SHA256"},
  { {0x00, 0xA7},
    "TLS_DH_anon_WITH_AES_256_GCM_SHA384",
     NULL,
    "TLS_DH_ANON_AES_256_GCM_SHA384"},
  { {0xC0, 0x84},
    "TLS_DH_anon_WITH_CAMELLIA_128_GCM_SHA256",
     NULL,
    "TLS_DH_ANON_CAMELLIA_128_GCM_SHA256"},
  { {0xC0, 0x85},
    "TLS_DH_anon_WITH_CAMELLIA_256_GCM_SHA384",
     NULL,
    "TLS_DH_ANON_CAMELLIA_256_GCM_SHA384"},
  { {0xC0, 0x15},
    "TLS_ECDH_anon_WITH_",
     NULL,
    "TLS_ECDH_ANON_NULL_SHA1"},
  { {0xC0, 0x17},
    "TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA",
     NULL,
    "TLS_ECDH_ANON_3DES_EDE_CBC_SHA1"},
  { {0xC0, 0x18},
    "TLS_ECDH_anon_WITH_AES_128_CBC_SHA",
     NULL,
    "TLS_ECDH_ANON_AES_128_CBC_SHA1"},
  { {0xC0, 0x19},
    "TLS_ECDH_anon_WITH_AES_256_CBC_SHA",
     NULL,
    "TLS_ECDH_ANON_AES_256_CBC_SHA1"},
  { {0xC0, 0x16},
    "TLS_ECDH_anon_WITH_RC4_128_SHA",
     NULL,
    "TLS_ECDH_ANON_ARCFOUR_128_SHA1"},
  { {0xC0, 0x1A},
    "TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA",
    "SRP-3DES-EDE-CBC-SHA",
    "TLS_SRP_SHA_3DES_EDE_CBC_SHA1"},
  { {0xC0, 0x1D},
    "TLS_SRP_SHA_WITH_AES_128_CBC_SHA",
    "SRP-AES-128-CBC-SHA",
    "TLS_SRP_SHA_AES_128_CBC_SHA1"},
  { {0xC0, 0x20},
    "TLS_SRP_SHA_WITH_AES_256_CBC_SHA",
    "SRP-AES-256-CBC-SHA",
    "TLS_SRP_SHA_AES_256_CBC_SHA1"},
  { {0xC0, 0x1C},
    "TLS_SRP_SHA_DSS_WITH_3DES_EDE_CBC_SHA",
     NULL,
    "TLS_SRP_SHA_DSS_3DES_EDE_CBC_SHA1"},
  { {0xC0, 0x1B},
    "TLS_SRP_SHA_RSA_WITH_3DES_EDE_CBC_SHA",
    "SRP-RSA-3DES-EDE-CBC-SHA",
    "TLS_SRP_SHA_RSA_3DES_EDE_CBC_SHA1"},
  { {0xC0, 0x1F},
    "TLS_SRP_SHA_DSS_WITH_AES_128_CBC_SHA",
     NULL,
    "TLS_SRP_SHA_DSS_AES_128_CBC_SHA1"},
  { {0xC0, 0x1E},
    "TLS_SRP_SHA_RSA_WITH_AES_128_CBC_SHA",
    "SRP-RSA-AES-128-CBC-SHA",
    "TLS_SRP_SHA_RSA_AES_128_CBC_SHA1"},
  { {0xC0, 0x22},
    "TLS_SRP_SHA_DSS_WITH_AES_256_CBC_SHA",
     NULL,
    "TLS_SRP_SHA_DSS_AES_256_CBC_SHA1"},
  { {0xC0, 0x21},
    "TLS_SRP_SHA_RSA_WITH_AES_256_CBC_SHA",
    "SRP-RSA-AES-256-CBC-SHA",
    "TLS_SRP_SHA_RSA_AES_256_CBC_SHA1"},
  { {0x00, 0x00},
    NULL,
    NULL,
    NULL}
};

/* map the gnutls cipher suite (defined by key exchange algorithm, cipher
   and mac algorithm) to the corresponding OpenSSL cipher name */
static const char *openssl_cipher_name(gnutls_kx_algorithm_t kx,
                                       gnutls_cipher_algorithm_t cipher,
                                       gnutls_mac_algorithm_t mac)
{
  unsigned int i=0;
  const char *name= 0;
  unsigned char sid[2];
  gnutls_kx_algorithm_t lkx;
  gnutls_cipher_algorithm_t lcipher;
  gnutls_mac_algorithm_t lmac;

  while ((name= gnutls_cipher_suite_info(i++, (unsigned char *)&sid, &lkx, &lcipher, &lmac, NULL)))
  {
    if (lkx == kx &&
        lcipher == cipher &&
        lmac == mac)
    {
      i=0;
      while (tls_ciphers[i].iana_name)
      {
        if (!memcmp(tls_ciphers[i].sid, &sid, 2))
        {
          if (tls_ciphers[i].openssl_name)
            return tls_ciphers[i].openssl_name;
          if (tls_ciphers[i].gnutls_name)
            return tls_ciphers[i].gnutls_name;
          return tls_ciphers[i].iana_name;
        }
        i++;
      }
    }
  }
  return NULL;
}

/* get priority string for a given openssl cipher name */
static char *get_priority(const char *cipher_name, char *priority, size_t len)
{
  unsigned int i= 0;
  while (tls_ciphers[i].iana_name)
  {
    if (strcmp(tls_ciphers[i].iana_name, cipher_name) == 0 ||
        (tls_ciphers[i].openssl_name &&
         strcmp(tls_ciphers[i].openssl_name, cipher_name) == 0) ||
        (tls_ciphers[i].gnutls_name &&
         strcmp(tls_ciphers[i].gnutls_name, cipher_name) == 0))
    {
      const char *name;
      gnutls_kx_algorithm_t kx;
      gnutls_cipher_algorithm_t cipher;
      gnutls_mac_algorithm_t mac;
      gnutls_protocol_t min_version;
      unsigned j= 0;

      if (!tls_ciphers[i].gnutls_name)
        return NULL;

      while ((name= gnutls_cipher_suite_info(j++, NULL, &kx, &cipher,
                                             &mac, &min_version)))
      {
        if (!strcmp(name, tls_ciphers[i].gnutls_name))
        {
          snprintf(priority, len - 1, ":+%s:+%s:+%s",
                   gnutls_cipher_get_name(cipher),
                   gnutls_mac_get_name(mac),
                   gnutls_kx_get_name(kx));
          return priority;
        }
      }
      return NULL;
    }
    i++;
  }
  return NULL;
}

#define MAX_SSL_ERR_LEN 100

static void ma_tls_set_error(MYSQL *mysql, void *ssl, int ssl_errno)
{
  char  ssl_error[MAX_SSL_ERR_LEN];
  const char *ssl_error_reason;
  MARIADB_PVIO *pvio= mysql->net.pvio;
  int save_errno= errno;

  /* give a more descriptive error message for alerts */
  if (ssl_errno == GNUTLS_E_FATAL_ALERT_RECEIVED)
  {
    gnutls_alert_description_t alert_desc;
    const char *alert_name;
    alert_desc= gnutls_alert_get((gnutls_session_t)ssl);
    alert_name= gnutls_alert_get_name(alert_desc);
    snprintf(ssl_error, MAX_SSL_ERR_LEN, "fatal alert received: %s",
             alert_name);
    pvio->set_error(mysql, CR_SSL_CONNECTION_ERROR, SQLSTATE_UNKNOWN, 0, ssl_error);
    return;
  }

  if (ssl_errno && (ssl_error_reason= gnutls_strerror(ssl_errno)))
  {
    pvio->set_error(mysql, CR_SSL_CONNECTION_ERROR, SQLSTATE_UNKNOWN, 0,
                   ssl_error_reason);
    return;
  }

  strerror_r(save_errno, ssl_error, MAX_SSL_ERR_LEN);
  pvio->set_error(mysql, CR_SSL_CONNECTION_ERROR, SQLSTATE_UNKNOWN, "TLS/SSL error: %s (%d)",
                  ssl_error, save_errno);
}


static void ma_tls_get_error(char *errmsg, size_t length, int ssl_errno)
{
  const char *ssl_error_reason;

  if (!ssl_errno)
  {
    strncpy(errmsg, "Unknown SSL error", length);
    return;
  }
  if ((ssl_error_reason= gnutls_strerror(ssl_errno)))
  {
    strncpy(errmsg, ssl_error_reason, length);
    return;
  }
  snprintf(errmsg, length, "SSL errno=%d", ssl_errno);
}

/*
  Initializes SSL and allocate global
  context SSL_context

  SYNOPSIS
    my_gnutls_start
      mysql        connection handle

  RETURN VALUES
    0  success
    1  error
*/
int ma_tls_start(char *errmsg, size_t errmsg_len)
{
  int rc= 0;

  if (ma_tls_initialized)
    return 0;

  pthread_mutex_init(&LOCK_gnutls_config,NULL);
  pthread_mutex_lock(&LOCK_gnutls_config);

  if ((rc= gnutls_global_init()) != GNUTLS_E_SUCCESS)
  {
    ma_tls_get_error(errmsg, errmsg_len, rc);
    goto end;
  }
  snprintf(tls_library_version, TLS_VERSION_LENGTH - 1, "GnuTLS %s",
          gnutls_check_version(NULL));

  ma_tls_initialized= TRUE;
end:
  pthread_mutex_unlock(&LOCK_gnutls_config);
  return rc;
}

/*
   Release SSL and free resources
   Will be automatically executed by 
   mysql_server_end() function

   SYNOPSIS
     my_gnutls_end()
       void

   RETURN VALUES
     void
*/
void ma_tls_end()
{
  if (ma_tls_initialized)
  {
    pthread_mutex_lock(&LOCK_gnutls_config);
    if (mariadb_deinitialize_ssl)
      gnutls_global_deinit();
    ma_tls_initialized= FALSE;
    pthread_mutex_unlock(&LOCK_gnutls_config);
    pthread_mutex_destroy(&LOCK_gnutls_config);
  }
  return;
}

static size_t ma_gnutls_get_protocol_version(const char *tls_version_option,
                                             char *priority_string,
                                             size_t prio_len)
{
  char tls_versions[128];

  tls_versions[0]= 0;
  if (!tls_version_option || !tls_version_option[0])
    goto end;


  if (strstr(tls_version_option, "TLSv1.0"))
    strcat(tls_versions, ":+VERS-TLS1.0");
  if (strstr(tls_version_option, "TLSv1.1"))
    strcat(tls_versions, ":+VERS-TLS1.1");
  if (strstr(tls_version_option, "TLSv1.2"))
    strcat(tls_versions, ":+VERS-TLS1.2");
#if GNUTLS_VERSION_NUMBER > 0x030605
  if (strstr(tls_version_option, "TLSv1.3"))
    strcat(tls_versions, ":+VERS-TLS1.3");
#endif
end:
  if (tls_versions[0])
    snprintf(priority_string, prio_len - 1, "-VERS-TLS-ALL%s:NORMAL", tls_versions);
  else
    strncpy(priority_string, "NORMAL:+VERS-ALL", prio_len - 1);
  return strlen(priority_string);
}

static int ma_gnutls_set_ciphers(gnutls_session_t ssl,
                                 const char *cipher_str,
                                 const char *tls_version)
{
  const char *err;
  char *token;
#define PRIO_SIZE 1024
  char prio[PRIO_SIZE];

  ma_gnutls_get_protocol_version(tls_version, prio, PRIO_SIZE);

  if (!cipher_str)
    return gnutls_priority_set_direct(ssl, prio, &err);

  token= strtok((char *)cipher_str, ":");

  strcpy(prio, "NONE:+VERS-TLS-ALL:+SIGN-ALL:+COMP-NULL:+CURVE-ALL");

  while (token)
  {
    char priority[1024];
    char *p= get_priority(token, priority, 1024);
    if (p)
      strncat(prio, p, PRIO_SIZE - strlen(prio) - 1);
    token = strtok(NULL, ":");
  }
  return gnutls_priority_set_direct(ssl, prio , &err);
}

static int ma_tls_set_certs(MYSQL *mysql,
                            gnutls_certificate_credentials_t ctx)
{
  int  ssl_error= 0;

  if (mysql->options.ssl_ca)
  {

    ssl_error= gnutls_certificate_set_x509_trust_file(ctx,
                                                      mysql->options.ssl_ca,
                                                      GNUTLS_X509_FMT_PEM);
    if (ssl_error < 0)
      goto error;
  }

  if (mysql->options.ssl_capath)
  {
    ssl_error=  gnutls_certificate_set_x509_trust_dir(ctx,
                                                      mysql->options.ssl_capath,
                                                      GNUTLS_X509_FMT_PEM);
    if (ssl_error < 0)
      goto error;
  }

  if (!mysql->options.ssl_ca && !mysql->options.ssl_capath)
  {
    ssl_error= gnutls_certificate_set_x509_system_trust(ctx);
    if (ssl_error < 0)
      goto error;
  }

  gnutls_certificate_set_verify_function(ctx,
                                         my_verify_callback);

  if (mysql->options.ssl_key || mysql->options.ssl_cert)
  {
    char *keyfile= mysql->options.ssl_key;
    char *certfile= mysql->options.ssl_cert;
    
    if (!certfile)
      certfile= keyfile;
    else if (!keyfile)
      keyfile= certfile;

    /* load cert/key into context */
    if ((ssl_error= gnutls_certificate_set_x509_key_file2(ctx,
                                certfile, keyfile, GNUTLS_X509_FMT_PEM,
                                 mysql->options.extension ? mysql->options.extension->tls_pw : NULL, 0)) < 0)
      goto error;
  }

error:
  return ssl_error;
}

void *ma_tls_init(MYSQL *mysql)
{
  gnutls_session_t ssl= NULL;
  gnutls_certificate_credentials_t ctx;
  int ssl_error= 0;

  pthread_mutex_lock(&LOCK_gnutls_config);

  if (gnutls_certificate_allocate_credentials(&ctx) != GNUTLS_E_SUCCESS)
    goto error;

  if ((ssl_error= ma_tls_set_certs(mysql, ctx)) < 0)
    goto error;

  if ((ssl_error = gnutls_init(&ssl, GNUTLS_CLIENT | GNUTLS_NONBLOCK | GNUTLS_NO_SIGNAL)) < 0)
    goto error;

  gnutls_session_set_ptr(ssl, (void *)mysql);
  /*
  gnutls_certificate_set_retrieve_function2(GNUTLS_xcred, client_cert_callback);
 */
  ssl_error= ma_gnutls_set_ciphers(ssl, mysql->options.ssl_cipher, mysql->options.extension ? mysql->options.extension->tls_version : NULL);
  if (ssl_error < 0)
    goto error;

  /* we don't load private key and cert by default - if the server requests
     a client certificate we will send it via callback function */
  if ((ssl_error= gnutls_credentials_set(ssl, GNUTLS_CRD_CERTIFICATE, ctx)) < 0)
    goto error;
  
  pthread_mutex_unlock(&LOCK_gnutls_config);
  return (void *)ssl;
error:
  ma_tls_set_error(mysql, ssl, ssl_error);
  gnutls_certificate_free_credentials(ctx);
  if (ssl)
    gnutls_deinit(ssl);
  pthread_mutex_unlock(&LOCK_gnutls_config);
  return NULL;
}

#ifdef GNUTLS_EXTERNAL_TRANSPORT
ssize_t ma_tls_push(gnutls_transport_ptr_t ptr, const void* data, size_t len)
{
  MARIADB_PVIO *pvio= (MARIADB_PVIO *)ptr;
  ssize_t rc= pvio->methods->write(pvio, data, len);
  return rc;
}

ssize_t ma_tls_pull(gnutls_transport_ptr_t ptr, void* data, size_t len)
{
  MARIADB_PVIO *pvio= (MARIADB_PVIO *)ptr;
  ssize_t rc= pvio->methods->read(pvio, data, len);
  return rc;
}

static int ma_tls_pull_timeout(gnutls_transport_ptr_t ptr, unsigned int ms)
{
  MARIADB_PVIO *pvio= (MARIADB_PVIO *)ptr;
  return pvio->methods->wait_io_or_timeout(pvio, 0, ms);
}
#endif

my_bool ma_tls_connect(MARIADB_TLS *ctls)
{
  gnutls_session_t ssl = (gnutls_session_t)ctls->ssl;
  my_bool blocking;
  MYSQL *mysql= (MYSQL *)gnutls_session_get_ptr(ssl);
  MARIADB_PVIO *pvio;
  int ret;

  if (!mysql)
    return 1;

  pvio= mysql->net.pvio;

  /* Set socket to blocking if not already set */
  if (!(blocking= pvio->methods->is_blocking(pvio)))
    pvio->methods->blocking(pvio, TRUE, 0);


#ifdef GNUTLS_EXTERNAL_TRANSPORT
  /* we don't use GnuTLS read/write functions */
  gnutls_transport_set_ptr(ssl, pvio);
  gnutls_transport_set_push_function(ssl, ma_tls_push);
  gnutls_transport_set_pull_function(ssl, ma_tls_pull);
  gnutls_transport_set_pull_timeout_function(ssl, ma_tls_pull_timeout);
  gnutls_handshake_set_timeout(ssl, pvio->timeout[PVIO_CONNECT_TIMEOUT]);
#else
  gnutls_transport_set_int(ssl, mysql_get_socket(mysql));
#endif

  do {
    ret = gnutls_handshake(ssl);
  } while (ret < 0 && gnutls_error_is_fatal(ret) == 0);

  if (ret < 0)
  {
    /* If error message was not set while calling certification callback function,
       use default error message (which is not very descriptive */
    if (!mysql_errno(mysql))
      ma_tls_set_error(mysql, ssl, ret);

    ma_tls_close(ctls);

    /* restore blocking mode */
    if (!blocking)
      pvio->methods->blocking(pvio, FALSE, 0);
    return 1;
  }
  ctls->ssl= (void *)ssl;
  return 0;
}

ssize_t ma_tls_write_async(MARIADB_PVIO *pvio, const uchar *buffer, size_t length)
{
  ssize_t res;
  struct mysql_async_context *b= pvio->mysql->options.extension->async_context;
  MARIADB_TLS *ctls= pvio->ctls;

  for (;;)
  {
    b->events_to_wait_for= 0;
    res= gnutls_record_send((gnutls_session_t)ctls->ssl, (void *)buffer, length);
    if (res > 0)
      return res;
    if (res == GNUTLS_E_AGAIN)
      b->events_to_wait_for|= MYSQL_WAIT_WRITE;
    else
      return res;
    if (b->suspend_resume_hook)
      (*b->suspend_resume_hook)(TRUE, b->suspend_resume_hook_user_data);
    my_context_yield(&b->async_context);
    if (b->suspend_resume_hook)
      (*b->suspend_resume_hook)(FALSE, b->suspend_resume_hook_user_data);
  }
}


ssize_t ma_tls_read_async(MARIADB_PVIO *pvio, const uchar *buffer, size_t length)
{
  ssize_t res;
  struct mysql_async_context *b= pvio->mysql->options.extension->async_context;
  MARIADB_TLS *ctls= pvio->ctls;

  for (;;)
  {
    b->events_to_wait_for= 0;
    res= gnutls_record_recv((gnutls_session_t)ctls->ssl, (void *)buffer, length);
    if (res > 0)
      return res;
    if (res == GNUTLS_E_AGAIN)
      b->events_to_wait_for|= MYSQL_WAIT_READ;
    else
      return res;
    if (b->suspend_resume_hook)
      (*b->suspend_resume_hook)(TRUE, b->suspend_resume_hook_user_data);
    my_context_yield(&b->async_context);
    if (b->suspend_resume_hook)
      (*b->suspend_resume_hook)(FALSE, b->suspend_resume_hook_user_data);
  }
}

ssize_t ma_tls_read(MARIADB_TLS *ctls, const uchar* buffer, size_t length)
{
  ssize_t rc;
  MARIADB_PVIO *pvio= ctls->pvio;

  while ((rc= gnutls_record_recv((gnutls_session_t)ctls->ssl, (void *)buffer, length)) <= 0)
  {
    if (rc != GNUTLS_E_AGAIN && rc != GNUTLS_E_INTERRUPTED)
      break;
    if (pvio->methods->wait_io_or_timeout(pvio, TRUE, pvio->mysql->options.read_timeout) < 1)
      break;
  }
  if (rc <= 0) {
    MYSQL *mysql= (MYSQL *)gnutls_session_get_ptr(ctls->ssl);
    ma_tls_set_error(mysql, ctls->ssl, rc);
  }
  return rc;
}

ssize_t ma_tls_write(MARIADB_TLS *ctls, const uchar* buffer, size_t length)
{ 
  ssize_t rc;
  MARIADB_PVIO *pvio= ctls->pvio;

  while ((rc= gnutls_record_send((gnutls_session_t)ctls->ssl, (void *)buffer, length)) <= 0)
  {
    if (rc != GNUTLS_E_AGAIN && rc != GNUTLS_E_INTERRUPTED)
      break;
    if (pvio->methods->wait_io_or_timeout(pvio, TRUE, pvio->mysql->options.write_timeout) < 1)
      break;
  }
  if (rc <= 0) {
    MYSQL *mysql= (MYSQL *)gnutls_session_get_ptr(ctls->ssl);
    ma_tls_set_error(mysql, ctls->ssl, rc);
  }
  return rc;
}

my_bool ma_tls_close(MARIADB_TLS *ctls)
{
  if (ctls->ssl)
  {
    gnutls_certificate_credentials_t ctx;
    /* this would be the correct way, however can't detect afterwards
       if the socket is closed or not, so we don't send encrypted 
       finish alert.
    rc= gnutls_bye((gnutls_session_t )ctls->ssl, GNUTLS_SHUT_WR);
    */
    gnutls_credentials_get(ctls->ssl, GNUTLS_CRD_CERTIFICATE, (void **)&ctx);
    gnutls_certificate_free_keys(ctx);
    gnutls_certificate_free_cas(ctx);
    gnutls_certificate_free_crls(ctx);
    gnutls_certificate_free_ca_names(ctx);
    gnutls_certificate_free_credentials(ctx);
    gnutls_deinit((gnutls_session_t )ctls->ssl);
    ctls->ssl= NULL;
  }
  return 0;
}

int ma_tls_verify_server_cert(MARIADB_TLS *ctls __attribute__((unused)))
{
  /* server verification is already handled before during handshake */
  return 0;
}

const char *ma_tls_get_cipher(MARIADB_TLS *ctls)
{
  gnutls_kx_algorithm_t kx;
  gnutls_cipher_algorithm_t cipher;
  gnutls_mac_algorithm_t mac;

  if (!ctls || !ctls->ssl)
    return NULL;

  mac= gnutls_mac_get((gnutls_session_t)ctls->ssl);
  cipher= gnutls_cipher_get((gnutls_session_t)ctls->ssl);
  kx= gnutls_kx_get((gnutls_session_t)ctls->ssl);
  return openssl_cipher_name(kx, cipher, mac);
}

static int my_verify_callback(gnutls_session_t ssl)
{
  unsigned int status= 0;
  MYSQL *mysql= (MYSQL *)gnutls_session_get_ptr(ssl);

  CLEAR_CLIENT_ERROR(mysql);

  if ((mysql->options.extension->tls_verify_server_cert))
  {
    const char *hostname= mysql->host;

    if (gnutls_certificate_verify_peers3 (ssl, hostname, &status) < 0)
      return GNUTLS_E_CERTIFICATE_ERROR;
  } else {
    if (gnutls_certificate_verify_peers2 (ssl, &status) < 0)
      return GNUTLS_E_CERTIFICATE_ERROR;
  }
  if (status & GNUTLS_CERT_INVALID)
  {
    gnutls_datum_t out;
    int type;
    /* accept self signed certificates if we don't have to verify server cert */
    if (!(mysql->options.extension->tls_verify_server_cert) &&
        (status & GNUTLS_CERT_SIGNER_NOT_FOUND))
      return 0;

    /* gnutls default error message "certificate validation failed" isn't very
       descriptive, so we provide more information about the error here */
    type= gnutls_certificate_type_get(ssl);
    gnutls_certificate_verification_status_print(status, type, &out, 0);
    my_set_error(mysql, CR_SSL_CONNECTION_ERROR, SQLSTATE_UNKNOWN,
                 ER(CR_SSL_CONNECTION_ERROR), out.data);
    gnutls_free(out.data);
    
    return GNUTLS_E_CERTIFICATE_ERROR;
  }
  

  return 0;
}

unsigned int ma_tls_get_finger_print(MARIADB_TLS *ctls, char *fp, unsigned int len)
{
  MYSQL *mysql;
  size_t fp_len= len;
  const gnutls_datum_t *cert_list;
  unsigned int cert_list_size;

  if (!ctls || !ctls->ssl)
    return 0;

  mysql= (MYSQL *)gnutls_session_get_ptr(ctls->ssl);

  cert_list = gnutls_certificate_get_peers (ctls->ssl, &cert_list_size);
  if (cert_list == NULL)
  {
    my_set_error(mysql, CR_SSL_CONNECTION_ERROR, SQLSTATE_UNKNOWN,
                        ER(CR_SSL_CONNECTION_ERROR), 
                        "Unable to get server certificate");
    return 0;
  }

  if (gnutls_fingerprint(GNUTLS_DIG_SHA1, &cert_list[0], fp, &fp_len) == 0)
    return fp_len;
  else
  {
    my_set_error(mysql, CR_SSL_CONNECTION_ERROR, SQLSTATE_UNKNOWN,
                        ER(CR_SSL_CONNECTION_ERROR),
                        "Finger print buffer too small");
    return 0;
  }
}

int ma_tls_get_protocol_version(MARIADB_TLS *ctls)
{
  if (!ctls || !ctls->ssl)
    return 1;

  return gnutls_protocol_get_version(ctls->ssl) - 1;
}

void ma_tls_set_connection(MYSQL *mysql)
{
  (void)gnutls_session_set_ptr(mysql->net.pvio->ctls->ssl, (void *)mysql);
}
#endif /* HAVE_GNUTLS */
