correction link libraries libcurl

Change-Id: I8be291ac6b9ec15f0f7bbaa8b434da9d319ae389
Signed-off-by: Angelo Mantellini (manangel) <angelo.mantellini@irt-systemx.fr>

1 files changed, 1323 insertions, 0 deletions

diff --git a/external/libcurl_android/jni/libcurl/lib/vtls/gtls.c b/external/libcurl_android/jni/libcurl/lib/vtls/gtls.c
new file mode 100755
index 00000000..d64f95dc
--- /dev/null
+++ b/external/libcurl_android/jni/libcurl/lib/vtls/gtls.c
@@ -0,0 +1,1323 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+/*
+ * Source file for all GnuTLS-specific code for the TLS/SSL layer. No code
+ * but vtls.c should ever call or use these functions.
+ *
+ * Note: don't use the GnuTLS' *_t variable type names in this source code,
+ * since they were not present in 1.0.X.
+ */
+
+#include "curl_setup.h"
+
+#ifdef USE_GNUTLS
+
+#include <gnutls/gnutls.h>
+#include <gnutls/x509.h>
+
+#ifdef USE_GNUTLS_NETTLE
+#include <gnutls/crypto.h>
+#include <nettle/md5.h>
+#else
+#include <gcrypt.h>
+#endif
+
+#include "urldata.h"
+#include "sendf.h"
+#include "inet_pton.h"
+#include "gtls.h"
+#include "vtls.h"
+#include "parsedate.h"
+#include "connect.h" /* for the connect timeout */
+#include "select.h"
+#include "rawstr.h"
+#include "warnless.h"
+
+#define _MPRINTF_REPLACE /* use our functions only */
+#include <curl/mprintf.h>
+#include "curl_memory.h"
+/* The last #include file should be: */
+#include "memdebug.h"
+
+/*
+ Some hackish cast macros based on:
+ http://library.gnome.org/devel/glib/unstable/glib-Type-Conversion-Macros.html
+*/
+#ifndef GNUTLS_POINTER_TO_INT_CAST
+#define GNUTLS_POINTER_TO_INT_CAST(p) ((int) (long) (p))
+#endif
+#ifndef GNUTLS_INT_TO_POINTER_CAST
+#define GNUTLS_INT_TO_POINTER_CAST(i) ((void*) (long) (i))
+#endif
+
+/* Enable GnuTLS debugging by defining GTLSDEBUG */
+/*#define GTLSDEBUG */
+
+#ifdef GTLSDEBUG
+static void tls_log_func(int level, const char *str)
+{
+    fprintf(stderr, "|<%d>| %s", level, str);
+}
+#endif
+static bool gtls_inited = FALSE;
+
+#if defined(GNUTLS_VERSION_NUMBER)
+#  if (GNUTLS_VERSION_NUMBER >= 0x020c00)
+#    undef gnutls_transport_set_lowat
+#    define gnutls_transport_set_lowat(A,B) Curl_nop_stmt
+#    define USE_GNUTLS_PRIORITY_SET_DIRECT 1
+#  endif
+#  if (GNUTLS_VERSION_NUMBER >= 0x020c03)
+#    define GNUTLS_MAPS_WINSOCK_ERRORS 1
+#  endif
+
+#  ifdef USE_NGHTTP2
+#    undef HAS_ALPN
+#    if (GNUTLS_VERSION_NUMBER >= 0x030200)
+#      define HAS_ALPN
+#    endif
+#  endif
+#endif
+
+/*
+ * Custom push and pull callback functions used by GNU TLS to read and write
+ * to the socket.  These functions are simple wrappers to send() and recv()
+ * (although here using the sread/swrite macros as defined by
+ * curl_setup_once.h).
+ * We use custom functions rather than the GNU TLS defaults because it allows
+ * us to get specific about the fourth "flags" argument, and to use arbitrary
+ * private data with gnutls_transport_set_ptr if we wish.
+ *
+ * When these custom push and pull callbacks fail, GNU TLS checks its own
+ * session-specific error variable, and when not set also its own global
+ * errno variable, in order to take appropriate action. GNU TLS does not
+ * require that the transport is actually a socket. This implies that for
+ * Windows builds these callbacks should ideally set the session-specific
+ * error variable using function gnutls_transport_set_errno or as a last
+ * resort global errno variable using gnutls_transport_set_global_errno,
+ * with a transport agnostic error value. This implies that some winsock
+ * error translation must take place in these callbacks.
+ *
+ * Paragraph above applies to GNU TLS versions older than 2.12.3, since
+ * this version GNU TLS does its own internal winsock error translation
+ * using system_errno() function.
+ */
+
+#if defined(USE_WINSOCK) && !defined(GNUTLS_MAPS_WINSOCK_ERRORS)
+#  define gtls_EINTR  4
+#  define gtls_EIO    5
+#  define gtls_EAGAIN 11
+static int gtls_mapped_sockerrno(void)
+{
+  switch(SOCKERRNO) {
+  case WSAEWOULDBLOCK:
+    return gtls_EAGAIN;
+  case WSAEINTR:
+    return gtls_EINTR;
+  default:
+    break;
+  }
+  return gtls_EIO;
+}
+#endif
+
+static ssize_t Curl_gtls_push(void *s, const void *buf, size_t len)
+{
+  ssize_t ret = swrite(GNUTLS_POINTER_TO_INT_CAST(s), buf, len);
+#if defined(USE_WINSOCK) && !defined(GNUTLS_MAPS_WINSOCK_ERRORS)
+  if(ret < 0)
+    gnutls_transport_set_global_errno(gtls_mapped_sockerrno());
+#endif
+  return ret;
+}
+
+static ssize_t Curl_gtls_pull(void *s, void *buf, size_t len)
+{
+  ssize_t ret = sread(GNUTLS_POINTER_TO_INT_CAST(s), buf, len);
+#if defined(USE_WINSOCK) && !defined(GNUTLS_MAPS_WINSOCK_ERRORS)
+  if(ret < 0)
+    gnutls_transport_set_global_errno(gtls_mapped_sockerrno());
+#endif
+  return ret;
+}
+
+/* Curl_gtls_init()
+ *
+ * Global GnuTLS init, called from Curl_ssl_init(). This calls functions that
+ * are not thread-safe and thus this function itself is not thread-safe and
+ * must only be called from within curl_global_init() to keep the thread
+ * situation under control!
+ */
+int Curl_gtls_init(void)
+{
+  int ret = 1;
+  if(!gtls_inited) {
+    ret = gnutls_global_init()?0:1;
+#ifdef GTLSDEBUG
+    gnutls_global_set_log_function(tls_log_func);
+    gnutls_global_set_log_level(2);
+#endif
+    gtls_inited = TRUE;
+  }
+  return ret;
+}
+
+int Curl_gtls_cleanup(void)
+{
+  if(gtls_inited) {
+    gnutls_global_deinit();
+    gtls_inited = FALSE;
+  }
+  return 1;
+}
+
+static void showtime(struct SessionHandle *data,
+                     const char *text,
+                     time_t stamp)
+{
+  struct tm buffer;
+  const struct tm *tm = &buffer;
+  CURLcode result = Curl_gmtime(stamp, &buffer);
+  if(result)
+    return;
+
+  snprintf(data->state.buffer,
+           BUFSIZE,
+           "\t %s: %s, %02d %s %4d %02d:%02d:%02d GMT\n",
+           text,
+           Curl_wkday[tm->tm_wday?tm->tm_wday-1:6],
+           tm->tm_mday,
+           Curl_month[tm->tm_mon],
+           tm->tm_year + 1900,
+           tm->tm_hour,
+           tm->tm_min,
+           tm->tm_sec);
+  infof(data, "%s\n", data->state.buffer);
+}
+
+static gnutls_datum_t load_file (const char *file)
+{
+  FILE *f;
+  gnutls_datum_t loaded_file = { NULL, 0 };
+  long filelen;
+  void *ptr;
+
+  if(!(f = fopen(file, "r")))
+    return loaded_file;
+  if(fseek(f, 0, SEEK_END) != 0
+     || (filelen = ftell(f)) < 0
+     || fseek(f, 0, SEEK_SET) != 0
+     || !(ptr = malloc((size_t)filelen)))
+    goto out;
+  if(fread(ptr, 1, (size_t)filelen, f) < (size_t)filelen) {
+    free(ptr);
+    goto out;
+  }
+
+  loaded_file.data = ptr;
+  loaded_file.size = (unsigned int)filelen;
+out:
+  fclose(f);
+  return loaded_file;
+}
+
+static void unload_file(gnutls_datum_t data) {
+  free(data.data);
+}
+
+
+/* this function does a SSL/TLS (re-)handshake */
+static CURLcode handshake(struct connectdata *conn,
+                          int sockindex,
+                          bool duringconnect,
+                          bool nonblocking)
+{
+  struct SessionHandle *data = conn->data;
+  struct ssl_connect_data *connssl = &conn->ssl[sockindex];
+  gnutls_session_t session = conn->ssl[sockindex].session;
+  curl_socket_t sockfd = conn->sock[sockindex];
+  long timeout_ms;
+  int rc;
+  int what;
+
+  for(;;) {
+    /* check allowed time left */
+    timeout_ms = Curl_timeleft(data, NULL, duringconnect);
+
+    if(timeout_ms < 0) {
+      /* no need to continue if time already is up */
+      failf(data, "SSL connection timeout");
+      return CURLE_OPERATION_TIMEDOUT;
+    }
+
+    /* if ssl is expecting something, check if it's available. */
+    if(connssl->connecting_state == ssl_connect_2_reading
+       || connssl->connecting_state == ssl_connect_2_writing) {
+
+      curl_socket_t writefd = ssl_connect_2_writing==
+        connssl->connecting_state?sockfd:CURL_SOCKET_BAD;
+      curl_socket_t readfd = ssl_connect_2_reading==
+        connssl->connecting_state?sockfd:CURL_SOCKET_BAD;
+
+      what = Curl_socket_ready(readfd, writefd,
+                               nonblocking?0:
+                               timeout_ms?timeout_ms:1000);
+      if(what < 0) {
+        /* fatal error */
+        failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO);
+        return CURLE_SSL_CONNECT_ERROR;
+      }
+      else if(0 == what) {
+        if(nonblocking)
+          return CURLE_OK;
+        else if(timeout_ms) {
+          /* timeout */
+          failf(data, "SSL connection timeout at %ld", timeout_ms);
+          return CURLE_OPERATION_TIMEDOUT;
+        }
+      }
+      /* socket is readable or writable */
+    }
+
+    rc = gnutls_handshake(session);
+
+    if((rc == GNUTLS_E_AGAIN) || (rc == GNUTLS_E_INTERRUPTED)) {
+      connssl->connecting_state =
+        gnutls_record_get_direction(session)?
+        ssl_connect_2_writing:ssl_connect_2_reading;
+      continue;
+      if(nonblocking)
+        return CURLE_OK;
+    }
+    else if((rc < 0) && !gnutls_error_is_fatal(rc)) {
+      const char *strerr = NULL;
+
+      if(rc == GNUTLS_E_WARNING_ALERT_RECEIVED) {
+        int alert = gnutls_alert_get(session);
+        strerr = gnutls_alert_get_name(alert);
+      }
+
+      if(strerr == NULL)
+        strerr = gnutls_strerror(rc);
+
+      failf(data, "gnutls_handshake() warning: %s", strerr);
+    }
+    else if(rc < 0) {
+      const char *strerr = NULL;
+
+      if(rc == GNUTLS_E_FATAL_ALERT_RECEIVED) {
+        int alert = gnutls_alert_get(session);
+        strerr = gnutls_alert_get_name(alert);
+      }
+
+      if(strerr == NULL)
+        strerr = gnutls_strerror(rc);
+
+      failf(data, "gnutls_handshake() failed: %s", strerr);
+      return CURLE_SSL_CONNECT_ERROR;
+    }
+
+    /* Reset our connect state machine */
+    connssl->connecting_state = ssl_connect_1;
+    return CURLE_OK;
+  }
+}
+
+static gnutls_x509_crt_fmt_t do_file_type(const char *type)
+{
+  if(!type || !type[0])
+    return GNUTLS_X509_FMT_PEM;
+  if(Curl_raw_equal(type, "PEM"))
+    return GNUTLS_X509_FMT_PEM;
+  if(Curl_raw_equal(type, "DER"))
+    return GNUTLS_X509_FMT_DER;
+  return -1;
+}
+
+static CURLcode
+gtls_connect_step1(struct connectdata *conn,
+                   int sockindex)
+{
+  struct SessionHandle *data = conn->data;
+  gnutls_session_t session;
+  int rc;
+  void *ssl_sessionid;
+  size_t ssl_idsize;
+  bool sni = TRUE; /* default is SNI enabled */
+#ifdef ENABLE_IPV6
+  struct in6_addr addr;
+#else
+  struct in_addr addr;
+#endif
+#ifndef USE_GNUTLS_PRIORITY_SET_DIRECT
+  static const int cipher_priority[] = {
+  /* These two ciphers were added to GnuTLS as late as ver. 3.0.1,
+     but this code path is only ever used for ver. < 2.12.0.
+     GNUTLS_CIPHER_AES_128_GCM,
+     GNUTLS_CIPHER_AES_256_GCM,
+  */
+    GNUTLS_CIPHER_AES_128_CBC,
+    GNUTLS_CIPHER_AES_256_CBC,
+    GNUTLS_CIPHER_CAMELLIA_128_CBC,
+    GNUTLS_CIPHER_CAMELLIA_256_CBC,
+    GNUTLS_CIPHER_3DES_CBC,
+  };
+  static const int cert_type_priority[] = { GNUTLS_CRT_X509, 0 };
+  static int protocol_priority[] = { 0, 0, 0, 0 };
+#else
+#define GNUTLS_CIPHERS "NORMAL:-ARCFOUR-128:-CTYPE-ALL:+CTYPE-X509"
+/* If GnuTLS was compiled without support for SRP it will error out if SRP is
+   requested in the priority string, so treat it specially
+ */
+#define GNUTLS_SRP "+SRP"
+  const char* prioritylist;
+  const char *err = NULL;
+#endif
+#ifdef HAS_ALPN
+  int protocols_size = 2;
+  gnutls_datum_t protocols[2];
+#endif
+
+  if(conn->ssl[sockindex].state == ssl_connection_complete)
+    /* to make us tolerant against being called more than once for the
+       same connection */
+    return CURLE_OK;
+
+  if(!gtls_inited)
+    Curl_gtls_init();
+
+  /* GnuTLS only supports SSLv3 and TLSv1 */
+  if(data->set.ssl.version == CURL_SSLVERSION_SSLv2) {
+    failf(data, "GnuTLS does not support SSLv2");
+    return CURLE_SSL_CONNECT_ERROR;
+  }
+  else if(data->set.ssl.version == CURL_SSLVERSION_SSLv3)
+    sni = FALSE; /* SSLv3 has no SNI */
+
+  /* allocate a cred struct */
+  rc = gnutls_certificate_allocate_credentials(&conn->ssl[sockindex].cred);
+  if(rc != GNUTLS_E_SUCCESS) {
+    failf(data, "gnutls_cert_all_cred() failed: %s", gnutls_strerror(rc));
+    return CURLE_SSL_CONNECT_ERROR;
+  }
+
+#ifdef USE_TLS_SRP
+  if(data->set.ssl.authtype == CURL_TLSAUTH_SRP) {
+    infof(data, "Using TLS-SRP username: %s\n", data->set.ssl.username);
+
+    rc = gnutls_srp_allocate_client_credentials(
+           &conn->ssl[sockindex].srp_client_cred);
+    if(rc != GNUTLS_E_SUCCESS) {
+      failf(data, "gnutls_srp_allocate_client_cred() failed: %s",
+            gnutls_strerror(rc));
+      return CURLE_OUT_OF_MEMORY;
+    }
+
+    rc = gnutls_srp_set_client_credentials(conn->ssl[sockindex].
+                                           srp_client_cred,
+                                           data->set.ssl.username,
+                                           data->set.ssl.password);
+    if(rc != GNUTLS_E_SUCCESS) {
+      failf(data, "gnutls_srp_set_client_cred() failed: %s",
+            gnutls_strerror(rc));
+      return CURLE_BAD_FUNCTION_ARGUMENT;
+    }
+  }
+#endif
+
+  if(data->set.ssl.CAfile) {
+    /* set the trusted CA cert bundle file */
+    gnutls_certificate_set_verify_flags(conn->ssl[sockindex].cred,
+                                        GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT);
+
+    rc = gnutls_certificate_set_x509_trust_file(conn->ssl[sockindex].cred,
+                                                data->set.ssl.CAfile,
+                                                GNUTLS_X509_FMT_PEM);
+    if(rc < 0) {
+      infof(data, "error reading ca cert file %s (%s)\n",
+            data->set.ssl.CAfile, gnutls_strerror(rc));
+      if(data->set.ssl.verifypeer)
+        return CURLE_SSL_CACERT_BADFILE;
+    }
+    else
+      infof(data, "found %d certificates in %s\n",
+            rc, data->set.ssl.CAfile);
+  }
+
+  if(data->set.ssl.CRLfile) {
+    /* set the CRL list file */
+    rc = gnutls_certificate_set_x509_crl_file(conn->ssl[sockindex].cred,
+                                              data->set.ssl.CRLfile,
+                                              GNUTLS_X509_FMT_PEM);
+    if(rc < 0) {
+      failf(data, "error reading crl file %s (%s)",
+            data->set.ssl.CRLfile, gnutls_strerror(rc));
+      return CURLE_SSL_CRL_BADFILE;
+    }
+    else
+      infof(data, "found %d CRL in %s\n",
+            rc, data->set.ssl.CRLfile);
+  }
+
+  /* Initialize TLS session as a client */
+  rc = gnutls_init(&conn->ssl[sockindex].session, GNUTLS_CLIENT);
+  if(rc != GNUTLS_E_SUCCESS) {
+    failf(data, "gnutls_init() failed: %d", rc);
+    return CURLE_SSL_CONNECT_ERROR;
+  }
+
+  /* convenient assign */
+  session = conn->ssl[sockindex].session;
+
+  if((0 == Curl_inet_pton(AF_INET, conn->host.name, &addr)) &&
+#ifdef ENABLE_IPV6
+     (0 == Curl_inet_pton(AF_INET6, conn->host.name, &addr)) &&
+#endif
+     sni &&
+     (gnutls_server_name_set(session, GNUTLS_NAME_DNS, conn->host.name,
+                             strlen(conn->host.name)) < 0))
+    infof(data, "WARNING: failed to configure server name indication (SNI) "
+          "TLS extension\n");
+
+  /* Use default priorities */
+  rc = gnutls_set_default_priority(session);
+  if(rc != GNUTLS_E_SUCCESS)
+    return CURLE_SSL_CONNECT_ERROR;
+
+#ifndef USE_GNUTLS_PRIORITY_SET_DIRECT
+  rc = gnutls_cipher_set_priority(session, cipher_priority);
+  if(rc != GNUTLS_E_SUCCESS)
+    return CURLE_SSL_CONNECT_ERROR;
+
+  /* Sets the priority on the certificate types supported by gnutls. Priority
+   is higher for types specified before others. After specifying the types
+   you want, you must append a 0. */
+  rc = gnutls_certificate_type_set_priority(session, cert_type_priority);
+  if(rc != GNUTLS_E_SUCCESS)
+    return CURLE_SSL_CONNECT_ERROR;
+
+  if(data->set.ssl.cipher_list != NULL) {
+    failf(data, "can't pass a custom cipher list to older GnuTLS"
+          " versions");
+    return CURLE_SSL_CONNECT_ERROR;
+  }
+
+  switch (data->set.ssl.version) {
+    case CURL_SSLVERSION_SSLv3:
+      protocol_priority[0] = GNUTLS_SSL3;
+      break;
+    case CURL_SSLVERSION_DEFAULT:
+    case CURL_SSLVERSION_TLSv1:
+      protocol_priority[0] = GNUTLS_TLS1_0;
+      protocol_priority[1] = GNUTLS_TLS1_1;
+      protocol_priority[2] = GNUTLS_TLS1_2;
+      break;
+    case CURL_SSLVERSION_TLSv1_0:
+      protocol_priority[0] = GNUTLS_TLS1_0;
+      break;
+    case CURL_SSLVERSION_TLSv1_1:
+      protocol_priority[0] = GNUTLS_TLS1_1;
+      break;
+    case CURL_SSLVERSION_TLSv1_2:
+      protocol_priority[0] = GNUTLS_TLS1_2;
+    break;
+      case CURL_SSLVERSION_SSLv2:
+    default:
+      failf(data, "GnuTLS does not support SSLv2");
+      return CURLE_SSL_CONNECT_ERROR;
+      break;
+  }
+  rc = gnutls_protocol_set_priority(session, protocol_priority);
+  if(rc != GNUTLS_E_SUCCESS) {
+    failf(data, "Did you pass a valid GnuTLS cipher list?");
+    return CURLE_SSL_CONNECT_ERROR;
+  }
+
+#else
+  /* Ensure +SRP comes at the *end* of all relevant strings so that it can be
+   * removed if a run-time error indicates that SRP is not supported by this
+   * GnuTLS version */
+  switch (data->set.ssl.version) {
+    case CURL_SSLVERSION_SSLv3:
+      prioritylist = GNUTLS_CIPHERS ":-VERS-TLS-ALL:+VERS-SSL3.0";
+      sni = false;
+      break;
+    case CURL_SSLVERSION_DEFAULT:
+    case CURL_SSLVERSION_TLSv1:
+      prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:" GNUTLS_SRP;
+      break;
+    case CURL_SSLVERSION_TLSv1_0:
+      prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
+                     "+VERS-TLS1.0:" GNUTLS_SRP;
+      break;
+    case CURL_SSLVERSION_TLSv1_1:
+      prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
+                     "+VERS-TLS1.1:" GNUTLS_SRP;
+      break;
+    case CURL_SSLVERSION_TLSv1_2:
+      prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
+                     "+VERS-TLS1.2:" GNUTLS_SRP;
+      break;
+    case CURL_SSLVERSION_SSLv2:
+    default:
+      failf(data, "GnuTLS does not support SSLv2");
+      return CURLE_SSL_CONNECT_ERROR;
+      break;
+  }
+  rc = gnutls_priority_set_direct(session, prioritylist, &err);
+  if((rc == GNUTLS_E_INVALID_REQUEST) && err) {
+    if(!strcmp(err, GNUTLS_SRP)) {
+      /* This GnuTLS was probably compiled without support for SRP.
+       * Note that fact and try again without it. */
+      int validprioritylen = curlx_uztosi(err - prioritylist);
+      char *prioritycopy = strdup(prioritylist);
+      if(!prioritycopy)
+        return CURLE_OUT_OF_MEMORY;
+
+      infof(data, "This GnuTLS does not support SRP\n");
+      if(validprioritylen)
+        /* Remove the :+SRP */
+        prioritycopy[validprioritylen - 1] = 0;
+      rc = gnutls_priority_set_direct(session, prioritycopy, &err);
+      free(prioritycopy);
+    }
+  }
+  if(rc != GNUTLS_E_SUCCESS) {
+    failf(data, "Error %d setting GnuTLS cipher list starting with %s",
+          rc, err);
+    return CURLE_SSL_CONNECT_ERROR;
+  }
+#endif
+
+#ifdef HAS_ALPN
+  if(data->set.httpversion == CURL_HTTP_VERSION_2_0) {
+    if(data->set.ssl_enable_alpn) {
+      protocols[0].data = NGHTTP2_PROTO_VERSION_ID;
+      protocols[0].size = NGHTTP2_PROTO_VERSION_ID_LEN;
+      protocols[1].data = ALPN_HTTP_1_1;
+      protocols[1].size = ALPN_HTTP_1_1_LENGTH;
+      gnutls_alpn_set_protocols(session, protocols, protocols_size, 0);
+      infof(data, "ALPN, offering %s, %s\n", NGHTTP2_PROTO_VERSION_ID,
+            ALPN_HTTP_1_1);
+    }
+    else {
+      infof(data, "SSL, can't negotiate HTTP/2.0 without ALPN\n");
+    }
+  }
+#endif
+
+  if(data->set.str[STRING_CERT]) {
+    if(gnutls_certificate_set_x509_key_file(
+         conn->ssl[sockindex].cred,
+         data->set.str[STRING_CERT],
+         data->set.str[STRING_KEY] ?
+         data->set.str[STRING_KEY] : data->set.str[STRING_CERT],
+         do_file_type(data->set.str[STRING_CERT_TYPE]) ) !=
+       GNUTLS_E_SUCCESS) {
+      failf(data, "error reading X.509 key or certificate file");
+      return CURLE_SSL_CONNECT_ERROR;
+    }
+  }
+
+#ifdef USE_TLS_SRP
+  /* put the credentials to the current session */
+  if(data->set.ssl.authtype == CURL_TLSAUTH_SRP) {
+    rc = gnutls_credentials_set(session, GNUTLS_CRD_SRP,
+                                conn->ssl[sockindex].srp_client_cred);
+    if(rc != GNUTLS_E_SUCCESS)
+      failf(data, "gnutls_credentials_set() failed: %s", gnutls_strerror(rc));
+  }
+  else
+#endif
+    rc = gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE,
+                                conn->ssl[sockindex].cred);
+
+  /* set the connection handle (file descriptor for the socket) */
+  gnutls_transport_set_ptr(session,
+                           GNUTLS_INT_TO_POINTER_CAST(conn->sock[sockindex]));
+
+  /* register callback functions to send and receive data. */
+  gnutls_transport_set_push_function(session, Curl_gtls_push);
+  gnutls_transport_set_pull_function(session, Curl_gtls_pull);
+
+  /* lowat must be set to zero when using custom push and pull functions. */
+  gnutls_transport_set_lowat(session, 0);
+
+  /* This might be a reconnect, so we check for a session ID in the cache
+     to speed up things */
+
+  if(!Curl_ssl_getsessionid(conn, &ssl_sessionid, &ssl_idsize)) {
+    /* we got a session id, use it! */
+    gnutls_session_set_data(session, ssl_sessionid, ssl_idsize);
+
+    /* Informational message */
+    infof (data, "SSL re-using session ID\n");
+  }
+
+  return CURLE_OK;
+}
+
+static Curl_recv gtls_recv;
+static Curl_send gtls_send;
+
+static CURLcode
+gtls_connect_step3(struct connectdata *conn,
+                   int sockindex)
+{
+  unsigned int cert_list_size;
+  const gnutls_datum_t *chainp;
+  unsigned int verify_status;
+  gnutls_x509_crt_t x509_cert,x509_issuer;
+  gnutls_datum_t issuerp;
+  char certbuf[256] = ""; /* big enough? */
+  size_t size;
+  unsigned int algo;
+  unsigned int bits;
+  time_t certclock;
+  const char *ptr;
+  struct SessionHandle *data = conn->data;
+  gnutls_session_t session = conn->ssl[sockindex].session;
+  int rc;
+  int incache;
+  void *ssl_sessionid;
+#ifdef HAS_ALPN
+  gnutls_datum_t proto;
+#endif
+  CURLcode result = CURLE_OK;
+
+  /* This function will return the peer's raw certificate (chain) as sent by
+     the peer. These certificates are in raw format (DER encoded for
+     X.509). In case of a X.509 then a certificate list may be present. The
+     first certificate in the list is the peer's certificate, following the
+     issuer's certificate, then the issuer's issuer etc. */
+
+  chainp = gnutls_certificate_get_peers(session, &cert_list_size);
+  if(!chainp) {
+    if(data->set.ssl.verifypeer ||
+       data->set.ssl.verifyhost ||
+       data->set.ssl.issuercert) {
+#ifdef USE_TLS_SRP
+      if(data->set.ssl.authtype == CURL_TLSAUTH_SRP
+         && data->set.ssl.username != NULL
+         && !data->set.ssl.verifypeer
+         && gnutls_cipher_get(session)) {
+        /* no peer cert, but auth is ok if we have SRP user and cipher and no
+           peer verify */
+      }
+      else {
+#endif
+        failf(data, "failed to get server cert");
+        return CURLE_PEER_FAILED_VERIFICATION;
+#ifdef USE_TLS_SRP
+      }
+#endif
+    }
+    infof(data, "\t common name: WARNING couldn't obtain\n");
+  }
+
+  if(data->set.ssl.verifypeer) {
+    /* This function will try to verify the peer's certificate and return its
+       status (trusted, invalid etc.). The value of status should be one or
+       more of the gnutls_certificate_status_t enumerated elements bitwise
+       or'd. To avoid denial of service attacks some default upper limits
+       regarding the certificate key size and chain size are set. To override
+       them use gnutls_certificate_set_verify_limits(). */
+
+    rc = gnutls_certificate_verify_peers2(session, &verify_status);
+    if(rc < 0) {
+      failf(data, "server cert verify failed: %d", rc);
+      return CURLE_SSL_CONNECT_ERROR;
+    }
+
+    /* verify_status is a bitmask of gnutls_certificate_status bits */
+    if(verify_status & GNUTLS_CERT_INVALID) {
+      if(data->set.ssl.verifypeer) {
+        failf(data, "server certificate verification failed. CAfile: %s "
+              "CRLfile: %s", data->set.ssl.CAfile?data->set.ssl.CAfile:"none",
+              data->set.ssl.CRLfile?data->set.ssl.CRLfile:"none");
+        return CURLE_SSL_CACERT;
+      }
+      else
+        infof(data, "\t server certificate verification FAILED\n");
+    }
+    else
+      infof(data, "\t server certificate verification OK\n");
+  }
+  else
+    infof(data, "\t server certificate verification SKIPPED\n");
+
+  /* initialize an X.509 certificate structure. */
+  gnutls_x509_crt_init(&x509_cert);
+
+  if(chainp)
+    /* convert the given DER or PEM encoded Certificate to the native
+       gnutls_x509_crt_t format */
+    gnutls_x509_crt_import(x509_cert, chainp, GNUTLS_X509_FMT_DER);
+
+  if(data->set.ssl.issuercert) {
+    gnutls_x509_crt_init(&x509_issuer);
+    issuerp = load_file(data->set.ssl.issuercert);
+    gnutls_x509_crt_import(x509_issuer, &issuerp, GNUTLS_X509_FMT_PEM);
+    rc = gnutls_x509_crt_check_issuer(x509_cert,x509_issuer);
+    unload_file(issuerp);
+    if(rc <= 0) {
+      failf(data, "server certificate issuer check failed (IssuerCert: %s)",
+            data->set.ssl.issuercert?data->set.ssl.issuercert:"none");
+      return CURLE_SSL_ISSUER_ERROR;
+    }
+    infof(data,"\t server certificate issuer check OK (Issuer Cert: %s)\n",
+          data->set.ssl.issuercert?data->set.ssl.issuercert:"none");
+  }
+
+  size=sizeof(certbuf);
+  rc = gnutls_x509_crt_get_dn_by_oid(x509_cert, GNUTLS_OID_X520_COMMON_NAME,
+                                     0, /* the first and only one */
+                                     FALSE,
+                                     certbuf,
+                                     &size);
+  if(rc) {
+    infof(data, "error fetching CN from cert:%s\n",
+          gnutls_strerror(rc));
+  }
+
+  /* This function will check if the given certificate's subject matches the
+     given hostname. This is a basic implementation of the matching described
+     in RFC2818 (HTTPS), which takes into account wildcards, and the subject
+     alternative name PKIX extension. Returns non zero on success, and zero on
+     failure. */
+  rc = gnutls_x509_crt_check_hostname(x509_cert, conn->host.name);
+#if GNUTLS_VERSION_NUMBER < 0x030306
+  /* Before 3.3.6, gnutls_x509_crt_check_hostname() didn't check IP
+     addresses. */
+  if(!rc) {
+#ifdef ENABLE_IPV6
+    #define use_addr in6_addr
+#else
+    #define use_addr in_addr
+#endif
+    unsigned char addrbuf[sizeof(struct use_addr)];
+    unsigned char certaddr[sizeof(struct use_addr)];
+    size_t addrlen = 0, certaddrlen;
+    int i;
+    int ret = 0;
+
+    if(Curl_inet_pton(AF_INET, conn->host.name, addrbuf) > 0)
+      addrlen = 4;
+#ifdef ENABLE_IPV6
+    else if(Curl_inet_pton(AF_INET6, conn->host.name, addrbuf) > 0)
+      addrlen = 16;
+#endif
+
+    if(addrlen) {
+      for(i=0; ; i++) {
+        certaddrlen = sizeof(certaddr);
+        ret = gnutls_x509_crt_get_subject_alt_name(x509_cert, i, certaddr,
+                                                   &certaddrlen, NULL);
+        /* If this happens, it wasn't an IP address. */
+        if(ret == GNUTLS_E_SHORT_MEMORY_BUFFER)
+          continue;
+        if(ret < 0)
+          break;
+        if(ret != GNUTLS_SAN_IPADDRESS)
+          continue;
+        if(certaddrlen == addrlen && !memcmp(addrbuf, certaddr, addrlen)) {
+          rc = 1;
+          break;
+        }
+      }
+    }
+  }
+#endif
+  if(!rc) {
+    if(data->set.ssl.verifyhost) {
+      failf(data, "SSL: certificate subject name (%s) does not match "
+            "target host name '%s'", certbuf, conn->host.dispname);
+      gnutls_x509_crt_deinit(x509_cert);
+      return CURLE_PEER_FAILED_VERIFICATION;
+    }
+    else
+      infof(data, "\t common name: %s (does not match '%s')\n",
+            certbuf, conn->host.dispname);
+  }
+  else
+    infof(data, "\t common name: %s (matched)\n", certbuf);
+
+  /* Check for time-based validity */
+  certclock = gnutls_x509_crt_get_expiration_time(x509_cert);
+
+  if(certclock == (time_t)-1) {
+    if(data->set.ssl.verifypeer) {
+      failf(data, "server cert expiration date verify failed");
+      return CURLE_SSL_CONNECT_ERROR;
+    }
+    else
+      infof(data, "\t server certificate expiration date verify FAILED\n");
+  }
+  else {
+    if(certclock < time(NULL)) {
+      if(data->set.ssl.verifypeer) {
+        failf(data, "server certificate expiration date has passed.");
+        return CURLE_PEER_FAILED_VERIFICATION;
+      }
+      else
+        infof(data, "\t server certificate expiration date FAILED\n");
+    }
+    else
+      infof(data, "\t server certificate expiration date OK\n");
+  }
+
+  certclock = gnutls_x509_crt_get_activation_time(x509_cert);
+
+  if(certclock == (time_t)-1) {
+    if(data->set.ssl.verifypeer) {
+      failf(data, "server cert activation date verify failed");
+      return CURLE_SSL_CONNECT_ERROR;
+    }
+    else
+      infof(data, "\t server certificate activation date verify FAILED\n");
+  }
+  else {
+    if(certclock > time(NULL)) {
+      if(data->set.ssl.verifypeer) {
+        failf(data, "server certificate not activated yet.");
+        return CURLE_PEER_FAILED_VERIFICATION;
+      }
+      else
+        infof(data, "\t server certificate activation date FAILED\n");
+    }
+    else
+      infof(data, "\t server certificate activation date OK\n");
+  }
+
+  /* Show:
+
+  - ciphers used
+  - subject
+  - start date
+  - expire date
+  - common name
+  - issuer
+
+  */
+
+  /* public key algorithm's parameters */
+  algo = gnutls_x509_crt_get_pk_algorithm(x509_cert, &bits);
+  infof(data, "\t certificate public key: %s\n",
+        gnutls_pk_algorithm_get_name(algo));
+
+  /* version of the X.509 certificate. */
+  infof(data, "\t certificate version: #%d\n",
+        gnutls_x509_crt_get_version(x509_cert));
+
+
+  size = sizeof(certbuf);
+  gnutls_x509_crt_get_dn(x509_cert, certbuf, &size);
+  infof(data, "\t subject: %s\n", certbuf);
+
+  certclock = gnutls_x509_crt_get_activation_time(x509_cert);
+  showtime(data, "start date", certclock);
+
+  certclock = gnutls_x509_crt_get_expiration_time(x509_cert);
+  showtime(data, "expire date", certclock);
+
+  size = sizeof(certbuf);
+  gnutls_x509_crt_get_issuer_dn(x509_cert, certbuf, &size);
+  infof(data, "\t issuer: %s\n", certbuf);
+
+  gnutls_x509_crt_deinit(x509_cert);
+
+  /* compression algorithm (if any) */
+  ptr = gnutls_compression_get_name(gnutls_compression_get(session));
+  /* the *_get_name() says "NULL" if GNUTLS_COMP_NULL is returned */
+  infof(data, "\t compression: %s\n", ptr);
+
+  /* the name of the cipher used. ie 3DES. */
+  ptr = gnutls_cipher_get_name(gnutls_cipher_get(session));
+  infof(data, "\t cipher: %s\n", ptr);
+
+  /* the MAC algorithms name. ie SHA1 */
+  ptr = gnutls_mac_get_name(gnutls_mac_get(session));
+  infof(data, "\t MAC: %s\n", ptr);
+
+#ifdef HAS_ALPN
+  if(data->set.ssl_enable_alpn) {
+    rc = gnutls_alpn_get_selected_protocol(session, &proto);
+    if(rc == 0) {
+      infof(data, "ALPN, server accepted to use %.*s\n", proto.size,
+          proto.data);
+
+      if(proto.size == NGHTTP2_PROTO_VERSION_ID_LEN &&
+        memcmp(NGHTTP2_PROTO_VERSION_ID, proto.data,
+        NGHTTP2_PROTO_VERSION_ID_LEN) == 0) {
+        conn->negnpn = NPN_HTTP2;
+      }
+      else if(proto.size == ALPN_HTTP_1_1_LENGTH && memcmp(ALPN_HTTP_1_1,
+          proto.data, ALPN_HTTP_1_1_LENGTH) == 0) {
+        conn->negnpn = NPN_HTTP1_1;
+      }
+    }
+    else {
+      infof(data, "ALPN, server did not agree to a protocol\n");
+    }
+  }
+#endif
+
+  conn->ssl[sockindex].state = ssl_connection_complete;
+  conn->recv[sockindex] = gtls_recv;
+  conn->send[sockindex] = gtls_send;
+
+  {
+    /* we always unconditionally get the session id here, as even if we
+       already got it from the cache and asked to use it in the connection, it
+       might've been rejected and then a new one is in use now and we need to
+       detect that. */
+    void *connect_sessionid;
+    size_t connect_idsize = 0;
+
+    /* get the session ID data size */
+    gnutls_session_get_data(session, NULL, &connect_idsize);
+    connect_sessionid = malloc(connect_idsize); /* get a buffer for it */
+
+    if(connect_sessionid) {
+      /* extract session ID to the allocated buffer */
+      gnutls_session_get_data(session, connect_sessionid, &connect_idsize);
+
+      incache = !(Curl_ssl_getsessionid(conn, &ssl_sessionid, NULL));
+      if(incache) {
+        /* there was one before in the cache, so instead of risking that the
+           previous one was rejected, we just kill that and store the new */
+        Curl_ssl_delsessionid(conn, ssl_sessionid);
+      }
+
+      /* store this session id */
+      result = Curl_ssl_addsessionid(conn, connect_sessionid, connect_idsize);
+      if(result) {
+        free(connect_sessionid);
+        result = CURLE_OUT_OF_MEMORY;
+      }
+    }
+    else
+      result = CURLE_OUT_OF_MEMORY;
+  }
+
+  return result;
+}
+
+
+/*
+ * This function is called after the TCP connect has completed. Setup the TLS
+ * layer and do all necessary magic.
+ */
+/* We use connssl->connecting_state to keep track of the connection status;
+   there are three states: 'ssl_connect_1' (not started yet or complete),
+   'ssl_connect_2_reading' (waiting for data from server), and
+   'ssl_connect_2_writing' (waiting to be able to write).
+ */
+static CURLcode
+gtls_connect_common(struct connectdata *conn,
+                    int sockindex,
+                    bool nonblocking,
+                    bool *done)
+{
+  int rc;
+  struct ssl_connect_data *connssl = &conn->ssl[sockindex];
+
+  /* Initiate the connection, if not already done */
+  if(ssl_connect_1==connssl->connecting_state) {
+    rc = gtls_connect_step1 (conn, sockindex);
+    if(rc)
+      return rc;
+  }
+
+  rc = handshake(conn, sockindex, TRUE, nonblocking);
+  if(rc)
+    /* handshake() sets its own error message with failf() */
+    return rc;
+
+  /* Finish connecting once the handshake is done */
+  if(ssl_connect_1==connssl->connecting_state) {
+    rc = gtls_connect_step3(conn, sockindex);
+    if(rc)
+      return rc;
+  }
+
+  *done = ssl_connect_1==connssl->connecting_state;
+
+  return CURLE_OK;
+}
+
+CURLcode
+Curl_gtls_connect_nonblocking(struct connectdata *conn,
+                              int sockindex,
+                              bool *done)
+{
+  return gtls_connect_common(conn, sockindex, TRUE, done);
+}
+
+CURLcode
+Curl_gtls_connect(struct connectdata *conn,
+                  int sockindex)
+
+{
+  CURLcode retcode;
+  bool done = FALSE;
+
+  retcode = gtls_connect_common(conn, sockindex, FALSE, &done);
+  if(retcode)
+    return retcode;
+
+  DEBUGASSERT(done);
+
+  return CURLE_OK;
+}
+
+static ssize_t gtls_send(struct connectdata *conn,
+                         int sockindex,
+                         const void *mem,
+                         size_t len,
+                         CURLcode *curlcode)
+{
+  ssize_t rc = gnutls_record_send(conn->ssl[sockindex].session, mem, len);
+
+  if(rc < 0 ) {
+    *curlcode = (rc == GNUTLS_E_AGAIN)
+      ? CURLE_AGAIN
+      : CURLE_SEND_ERROR;
+
+    rc = -1;
+  }
+
+  return rc;
+}
+
+void Curl_gtls_close_all(struct SessionHandle *data)
+{
+  /* FIX: make the OpenSSL code more generic and use parts of it here */
+  (void)data;
+}
+
+static void close_one(struct connectdata *conn,
+                      int idx)
+{
+  if(conn->ssl[idx].session) {
+    gnutls_bye(conn->ssl[idx].session, GNUTLS_SHUT_RDWR);
+    gnutls_deinit(conn->ssl[idx].session);
+    conn->ssl[idx].session = NULL;
+  }
+  if(conn->ssl[idx].cred) {
+    gnutls_certificate_free_credentials(conn->ssl[idx].cred);
+    conn->ssl[idx].cred = NULL;
+  }
+#ifdef USE_TLS_SRP
+  if(conn->ssl[idx].srp_client_cred) {
+    gnutls_srp_free_client_credentials(conn->ssl[idx].srp_client_cred);
+    conn->ssl[idx].srp_client_cred = NULL;
+  }
+#endif
+}
+
+void Curl_gtls_close(struct connectdata *conn, int sockindex)
+{
+  close_one(conn, sockindex);
+}
+
+/*
+ * This function is called to shut down the SSL layer but keep the
+ * socket open (CCC - Clear Command Channel)
+ */
+int Curl_gtls_shutdown(struct connectdata *conn, int sockindex)
+{
+  ssize_t result;
+  int retval = 0;
+  struct SessionHandle *data = conn->data;
+  int done = 0;
+  char buf[120];
+
+  /* This has only been tested on the proftpd server, and the mod_tls code
+     sends a close notify alert without waiting for a close notify alert in
+     response. Thus we wait for a close notify alert from the server, but
+     we do not send one. Let's hope other servers do the same... */
+
+  if(data->set.ftp_ccc == CURLFTPSSL_CCC_ACTIVE)
+      gnutls_bye(conn->ssl[sockindex].session, GNUTLS_SHUT_WR);
+
+  if(conn->ssl[sockindex].session) {
+    while(!done) {
+      int what = Curl_socket_ready(conn->sock[sockindex],
+                                   CURL_SOCKET_BAD, SSL_SHUTDOWN_TIMEOUT);
+      if(what > 0) {
+        /* Something to read, let's do it and hope that it is the close
+           notify alert from the server */
+        result = gnutls_record_recv(conn->ssl[sockindex].session,
+                                    buf, sizeof(buf));
+        switch(result) {
+        case 0:
+          /* This is the expected response. There was no data but only
+             the close notify alert */
+          done = 1;
+          break;
+        case GNUTLS_E_AGAIN:
+        case GNUTLS_E_INTERRUPTED:
+          infof(data, "GNUTLS_E_AGAIN || GNUTLS_E_INTERRUPTED\n");
+          break;
+        default:
+          retval = -1;
+          done = 1;
+          break;
+        }
+      }
+      else if(0 == what) {
+        /* timeout */
+        failf(data, "SSL shutdown timeout");
+        done = 1;
+        break;
+      }
+      else {
+        /* anything that gets here is fatally bad */
+        failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO);
+        retval = -1;
+        done = 1;
+      }
+    }
+    gnutls_deinit(conn->ssl[sockindex].session);
+  }
+  gnutls_certificate_free_credentials(conn->ssl[sockindex].cred);
+
+#ifdef USE_TLS_SRP
+  if(data->set.ssl.authtype == CURL_TLSAUTH_SRP
+     && data->set.ssl.username != NULL)
+    gnutls_srp_free_client_credentials(conn->ssl[sockindex].srp_client_cred);
+#endif
+
+  conn->ssl[sockindex].cred = NULL;
+  conn->ssl[sockindex].session = NULL;
+
+  return retval;
+}
+
+static ssize_t gtls_recv(struct connectdata *conn, /* connection data */
+                         int num,                  /* socketindex */
+                         char *buf,                /* store read data here */
+                         size_t buffersize,        /* max amount to read */
+                         CURLcode *curlcode)
+{
+  ssize_t ret;
+
+  ret = gnutls_record_recv(conn->ssl[num].session, buf, buffersize);
+  if((ret == GNUTLS_E_AGAIN) || (ret == GNUTLS_E_INTERRUPTED)) {
+    *curlcode = CURLE_AGAIN;
+    return -1;
+  }
+
+  if(ret == GNUTLS_E_REHANDSHAKE) {
+    /* BLOCKING call, this is bad but a work-around for now. Fixing this "the
+       proper way" takes a whole lot of work. */
+    CURLcode rc = handshake(conn, num, FALSE, FALSE);
+    if(rc)
+      /* handshake() writes error message on its own */
+      *curlcode = rc;
+    else
+      *curlcode = CURLE_AGAIN; /* then return as if this was a wouldblock */
+    return -1;
+  }
+
+  if(ret < 0) {
+    failf(conn->data, "GnuTLS recv error (%d): %s",
+          (int)ret, gnutls_strerror((int)ret));
+    *curlcode = CURLE_RECV_ERROR;
+    return -1;
+  }
+
+  return ret;
+}
+
+void Curl_gtls_session_free(void *ptr)
+{
+  free(ptr);
+}
+
+size_t Curl_gtls_version(char *buffer, size_t size)
+{
+  return snprintf(buffer, size, "GnuTLS/%s", gnutls_check_version(NULL));
+}
+
+#ifndef USE_GNUTLS_NETTLE
+static int Curl_gtls_seed(struct SessionHandle *data)
+{
+  /* we have the "SSL is seeded" boolean static to prevent multiple
+     time-consuming seedings in vain */
+  static bool ssl_seeded = FALSE;
+
+  /* Quickly add a bit of entropy */
+  gcry_fast_random_poll();
+
+  if(!ssl_seeded || data->set.str[STRING_SSL_RANDOM_FILE] ||
+     data->set.str[STRING_SSL_EGDSOCKET]) {
+
+    /* TODO: to a good job seeding the RNG
+       This may involve the gcry_control function and these options:
+       GCRYCTL_SET_RANDOM_SEED_FILE
+       GCRYCTL_SET_RNDEGD_SOCKET
+    */
+    ssl_seeded = TRUE;
+  }
+  return 0;
+}
+#endif
+
+/* data might be NULL! */
+int Curl_gtls_random(struct SessionHandle *data,
+                     unsigned char *entropy,
+                     size_t length)
+{
+#if defined(USE_GNUTLS_NETTLE)
+  (void)data;
+  gnutls_rnd(GNUTLS_RND_RANDOM, entropy, length);
+#elif defined(USE_GNUTLS)
+  if(data)
+    Curl_gtls_seed(data); /* Initiate the seed if not already done */
+  gcry_randomize(entropy, length, GCRY_STRONG_RANDOM);
+#endif
+  return 0;
+}
+
+void Curl_gtls_md5sum(unsigned char *tmp, /* input */
+                      size_t tmplen,
+                      unsigned char *md5sum, /* output */
+                      size_t md5len)
+{
+#if defined(USE_GNUTLS_NETTLE)
+  struct md5_ctx MD5pw;
+  md5_init(&MD5pw);
+  md5_update(&MD5pw, (unsigned int)tmplen, tmp);
+  md5_digest(&MD5pw, (unsigned int)md5len, md5sum);
+#elif defined(USE_GNUTLS)
+  gcry_md_hd_t MD5pw;
+  gcry_md_open(&MD5pw, GCRY_MD_MD5, 0);
+  gcry_md_write(MD5pw, tmp, tmplen);
+  memcpy(md5sum, gcry_md_read (MD5pw, 0), md5len);
+  gcry_md_close(MD5pw);
+#endif
+}
+
+#endif /* USE_GNUTLS */