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/*
 * Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation
 *
 * Author: Nikos Mavroyanopoulos
 *
 * This file is part of GNUTLS.
 *
 * The GNUTLS library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
 * USA
 *
 */

/* Here lies the code of the gnutls_*_set_priority() functions.
 */

#include "gnutls_int.h"
#include "gnutls_algorithms.h"
#include "gnutls_errors.h"
#include <gnutls_num.h>

/**
  * gnutls_cipher_set_priority - Sets the priority on the ciphers supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  * @list: is a 0 terminated list of gnutls_cipher_algorithm_t elements.
  *
  * Sets the priority on the ciphers supported by gnutls.
  * Priority is higher for elements specified before others.
  * After specifying the ciphers you want, you must append a 0.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_cipher_set_priority (gnutls_session_t session, const int *list)
{
  int num = 0, i;

  while (list[num] != 0)
    num++;
  if (num > MAX_ALGOS)
    num = MAX_ALGOS;
  session->internals.cipher_algorithm_priority.algorithms = num;

  for (i = 0; i < num; i++)
    {
      session->internals.cipher_algorithm_priority.priority[i] = list[i];
    }

  return 0;
}

/**
  * gnutls_kx_set_priority - Sets the priority on the key exchange algorithms supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  * @list: is a 0 terminated list of gnutls_kx_algorithm_t elements.
  *
  * Sets the priority on the key exchange algorithms supported by gnutls.
  * Priority is higher for elements specified before others.
  * After specifying the algorithms you want, you must append a 0.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * Returns 0 on success.
  *
 **/
int
gnutls_kx_set_priority (gnutls_session_t session, const int *list)
{
  int num = 0, i;

  while (list[num] != 0)
    num++;
  if (num > MAX_ALGOS)
    num = MAX_ALGOS;
  session->internals.kx_algorithm_priority.algorithms = num;

  for (i = 0; i < num; i++)
    {
      session->internals.kx_algorithm_priority.priority[i] = list[i];
    }

  return 0;
}

/**
  * gnutls_mac_set_priority - Sets the priority on the mac algorithms supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  * @list: is a 0 terminated list of gnutls_mac_algorithm_t elements.
  *
  * Sets the priority on the mac algorithms supported by gnutls.
  * Priority is higher for elements specified before others.
  * After specifying the algorithms you want, you must append a 0.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_mac_set_priority (gnutls_session_t session, const int *list)
{
  int num = 0, i;

  while (list[num] != 0)
    num++;
  if (num > MAX_ALGOS)
    num = MAX_ALGOS;
  session->internals.mac_algorithm_priority.algorithms = num;

  for (i = 0; i < num; i++)
    {
      session->internals.mac_algorithm_priority.priority[i] = list[i];
    }

  return 0;
}

/**
  * gnutls_compression_set_priority - Sets the priority on the compression algorithms supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  * @list: is a 0 terminated list of gnutls_compression_method_t elements.
  *
  * Sets the priority on the compression algorithms supported by gnutls.
  * Priority is higher for elements specified before others.
  * After specifying the algorithms you want, you must append a 0.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * TLS 1.0 does not define any compression algorithms except
  * NULL. Other compression algorithms are to be considered
  * as gnutls extensions.
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_compression_set_priority (gnutls_session_t session, const int *list)
{
  int num = 0, i;

  while (list[num] != 0)
    num++;
  if (num > MAX_ALGOS)
    num = MAX_ALGOS;
  session->internals.compression_method_priority.algorithms = num;

  for (i = 0; i < num; i++)
    {
      session->internals.compression_method_priority.priority[i] = list[i];
    }
  return 0;
}

/**
  * gnutls_protocol_set_priority - Sets the priority on the protocol versions supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  * @list: is a 0 terminated list of gnutls_protocol_t elements.
  *
  * Sets the priority on the protocol versions supported by gnutls.
  * This function actually enables or disables protocols. Newer protocol
  * versions always have highest priority.
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_protocol_set_priority (gnutls_session_t session, const int *list)
{
  int num = 0, i;

  while (list[num] != 0)
    num++;
  if (num > MAX_ALGOS)
    num = MAX_ALGOS;
  session->internals.protocol_priority.algorithms = num;

  for (i = 0; i < num; i++)
    {
      session->internals.protocol_priority.priority[i] = list[i];
    }

  /* set the current version to the first in the chain.
   * This will be overridden later.
   */
  if (num > 0)
    _gnutls_set_current_version (session, list[0]);

  return 0;
}

/**
  * gnutls_certificate_type_set_priority - Sets the priority on the certificate types supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  * @list: is a 0 terminated list of gnutls_certificate_type_t elements.
  *
  * Sets the priority on the certificate types supported by gnutls.
  * Priority is higher for elements specified before others.
  * After specifying the types you want, you must append a 0.
  * Note that the certificate type priority is set on the client. 
  * The server does not use the cert type priority except for disabling
  * types that were not specified.
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_certificate_type_set_priority (gnutls_session_t session,
				      const int *list)
{
#ifdef ENABLE_OPENPGP

  int num = 0, i;

  while (list[num] != 0)
    num++;
  if (num > MAX_ALGOS)
    num = MAX_ALGOS;
  session->internals.cert_type_priority.algorithms = num;

  for (i = 0; i < num; i++)
    {
      session->internals.cert_type_priority.priority[i] = list[i];
    }

  return 0;

#else

  return GNUTLS_E_UNIMPLEMENTED_FEATURE;

#endif
}

/**
  * gnutls_set_default_priority - Sets some default priority on the cipher suites supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  *
  * Sets some default priority on the ciphers, key exchange methods,
  * macs and compression methods. This is to avoid using the
  * gnutls_*_priority() functions, if these defaults are ok.  You may
  * override any of the following priorities by calling the
  * appropriate functions.
  *
  * The default order is:
  * Protocols: TLS 1.2, TLS 1.1, TLS 1.0, and SSL3.
  * Key exchange algorithm: DHE-PSK, PSK, SRP-RSA, SRP-DSS, SRP,
  * DHE-RSA, DHE-DSS, RSA.
  * Cipher: AES_256_CBC, AES_128_CBC, 3DES_CBC, CAMELLIA_128_CBC, 
  * and ARCFOUR_128.
  * MAC algorithm: SHA, and MD5.
  * Certificate types: X.509, OpenPGP
  * Compression: DEFLATE, NULL.
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_set_default_priority (gnutls_session_t session)
{

  gnutls_set_default_priority2( session, GNUTLS_PRIORITIES_SECURITY);

  return 0;
}

static const int protocol_priority[] = {
 /* GNUTLS_TLS1_2, -- not finalized yet! */
 GNUTLS_TLS1_1,
 GNUTLS_TLS1_0,
 GNUTLS_SSL3,
 0
};

static const int kx_priority_performance[] = {
  GNUTLS_KX_RSA,
  GNUTLS_KX_DHE_RSA,
  GNUTLS_KX_DHE_DSS,
  GNUTLS_KX_PSK,
  GNUTLS_KX_DHE_PSK,
  GNUTLS_KX_SRP_RSA,
  GNUTLS_KX_SRP_DSS,
  GNUTLS_KX_SRP,
  /* GNUTLS_KX_ANON_DH: Man-in-the-middle prone, don't add!
   * GNUTLS_KX_RSA_EXPORT: Deprecated, don't add!
   */
  0
};

static const int kx_priority_export[] = {
  GNUTLS_KX_RSA,
  GNUTLS_KX_DHE_RSA,
  GNUTLS_KX_DHE_DSS,
  GNUTLS_KX_PSK,
  GNUTLS_KX_DHE_PSK,
  GNUTLS_KX_SRP_RSA,
  GNUTLS_KX_SRP_DSS,
  GNUTLS_KX_SRP,
  GNUTLS_KX_RSA_EXPORT,
  0
};

static const int kx_priority_security[] = {
  /* The ciphersuites that offer forward secrecy take
   * precendance
   */
  GNUTLS_KX_DHE_RSA,
  GNUTLS_KX_DHE_DSS,
  GNUTLS_KX_DHE_PSK,
  GNUTLS_KX_SRP_RSA,
  GNUTLS_KX_SRP_DSS,
  GNUTLS_KX_RSA,
  GNUTLS_KX_PSK,
  GNUTLS_KX_SRP,
  /* GNUTLS_KX_ANON_DH: Man-in-the-middle prone, don't add!
   * GNUTLS_KX_RSA_EXPORT: Deprecated, don't add!
   */
  0
};

static const int cipher_priority_performance[] = {
  GNUTLS_CIPHER_ARCFOUR_128,
  GNUTLS_CIPHER_AES_128_CBC,
#ifdef	ENABLE_CAMELLIA
    GNUTLS_CIPHER_CAMELLIA_128_CBC,
#endif
  GNUTLS_CIPHER_AES_256_CBC,
  GNUTLS_CIPHER_3DES_CBC,
  /* GNUTLS_CIPHER_ARCFOUR_40: Insecure, don't add! */
  0
};


static const int cipher_priority_security[] = {
  GNUTLS_CIPHER_AES_256_CBC,
  GNUTLS_CIPHER_AES_128_CBC,
#ifdef	ENABLE_CAMELLIA
    GNUTLS_CIPHER_CAMELLIA_128_CBC,
#endif
  GNUTLS_CIPHER_3DES_CBC,
  GNUTLS_CIPHER_ARCFOUR_128,
  /* GNUTLS_CIPHER_ARCFOUR_40: Insecure, don't add! */
  0
};

static const int cipher_priority_export[] = {
  GNUTLS_CIPHER_ARCFOUR_128,
  GNUTLS_CIPHER_AES_128_CBC,
#ifdef	ENABLE_CAMELLIA
    GNUTLS_CIPHER_CAMELLIA_128_CBC,
#endif
  GNUTLS_CIPHER_AES_256_CBC,
  GNUTLS_CIPHER_3DES_CBC,
  GNUTLS_CIPHER_ARCFOUR_40,
  0
};

static const int comp_priority[] = {
  /* compression should be explicitely requested to be enabled */
  GNUTLS_COMP_NULL,
  0
};


static const int mac_priority_performance[] = {
  GNUTLS_MAC_MD5,
  GNUTLS_MAC_SHA1,
  0
};

static const int mac_priority_security[] = {
  GNUTLS_MAC_SHA1,
  GNUTLS_MAC_MD5,
  0
};

#define mac_priority_export mac_priority_security

static int cert_type_priority[] = {
  GNUTLS_CRT_X509,
  GNUTLS_CRT_OPENPGP,
  0
};


/**
  * gnutls_set_default_priority2 - Sets some default priority on the cipher suites supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  *
  * Sets some default priority on the ciphers, key exchange methods,
  * macs and compression methods. This is to avoid using the
  * gnutls_*_priority() functions, if these defaults are ok.  You may
  * override any of the following priorities by calling the
  * appropriate functions.
  *
  * The default order is:
  * Protocols: TLS 1.1, TLS 1.0, and SSL3.
  * Compression: NULL.
  * Certificate types: X.509, OpenPGP
  *
  * When performance is requested the fastest ciphers and key exchange
  * methods are used, whilst in security, the most conservative options
  * are set.
  *
  * Returns 0 on success.
  *
  **/
void
gnutls_set_default_priority2 (gnutls_session_t session, gnutls_priority_t flag)
{

  if (flag == GNUTLS_PRIORITIES_PERFORMANCE) {
    gnutls_cipher_set_priority (session, cipher_priority_performance);
    gnutls_kx_set_priority (session, kx_priority_performance);
    gnutls_mac_set_priority (session, mac_priority_performance);
  } else if (flag == GNUTLS_PRIORITIES_SECURITY) {
    gnutls_cipher_set_priority (session, cipher_priority_security);
    gnutls_kx_set_priority (session, kx_priority_security);
    gnutls_mac_set_priority (session, mac_priority_security);
  } else if (flag == GNUTLS_PRIORITIES_EXPORT) {
    gnutls_cipher_set_priority (session, cipher_priority_export);
    gnutls_kx_set_priority (session, kx_priority_export);
    gnutls_mac_set_priority (session, mac_priority_export);
  }

  gnutls_protocol_set_priority (session, protocol_priority);
  gnutls_compression_set_priority (session, comp_priority);
  gnutls_certificate_type_set_priority (session, cert_type_priority);

  return;
}


/**
  * gnutls_set_default_export_priority - Sets some default priority on the cipher suites supported by gnutls.
  * @session: is a #gnutls_session_t structure.
  *
  * Sets some default priority on the ciphers, key exchange methods, macs
  * and compression methods. This is to avoid using the gnutls_*_priority() functions, if
  * these defaults are ok. This function also includes weak algorithms.
  * The order is TLS1, SSL3 for protocols,  RSA, DHE_DSS, 
  * DHE_RSA, RSA_EXPORT for key exchange algorithms.
  * SHA, MD5, RIPEMD160 for MAC algorithms,
  * AES_256_CBC, AES_128_CBC, 3DES_CBC, CAMELLIA_128_CBC, 
  * ARCFOUR_128, ARCFOUR_40 for ciphers.
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_set_default_export_priority (gnutls_session_t session)
{
  gnutls_set_default_priority2( session, GNUTLS_PRIORITIES_EXPORT);

  return 0;
}

/* New priority API with strings
 */

/* Breaks a list of "xxx", "yyy", to a character array, of
 * MAX_COMMA_SEP_ELEMENTS size; Note that the given string is modified.
  */
static void break_comma_list(char *etag,
		      char **broken_etag, int* elements, int max_elements,
		      char sep)
{
    char *p = etag;
    if (sep == 0) sep = ',';

    *elements = 0;

    do {
	broken_etag[*elements] = p;

	(*elements)++;

	p = strchr(p, sep);
	if (p) {
	    *p = 0;
	    p++;		/* move to next entry and skip white
				 * space.
				 */
	    while (*p == ' ')
		p++;
	}
    } while (p != NULL && *elements < max_elements);
}

#if defined(__STDC_VERSION__) && __STD_VERSION__ > 199901L
#define _GNUTLS_MAX_PRIO (out_priority_len-1)
#define _GNUTLS_MAX_PRIO_CHECK(x)
#else
#define _GNUTLS_MAX_PRIO 256
#define _GNUTLS_MAX_PRIO_CHECK(x) if (x>255) return GNUTLS_E_INVALID_REQUEST
#endif

/**
  * gnutls_mac_convert_priority - Converts the priority on the MAC algorithms supported by gnutls.
  * @out_priority: is a list of integers to copy priorities to
  * @out_priority_len: is the maximum number of integers the previous list can hold
  * @prio: is a separated list of algorithms
  * @sep: is the separator of the previous list, if zero comma is assumed
  *
  * Converts the priority on the MAC algorithms supported by gnutls to 
  * internal integer format
  * Priority is higher for elements specified before others.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * The supported algorithms are: MD5, SHA1
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_mac_convert_priority (int* out_priority, int out_priority_len, const char *prio, char sep)
{
    char *broken_list[_GNUTLS_MAX_PRIO];
    int broken_list_size, i, j;
    char* darg;
    int ret;
    
    _GNUTLS_MAX_PRIO_CHECK(out_priority_len);
    
    darg = gnutls_strdup( prio);
    if (darg == NULL) {
      gnutls_assert();
      return GNUTLS_E_MEMORY_ERROR;
    }

    break_comma_list(darg, broken_list, &broken_list_size, out_priority_len-1, sep);

    j = 0;
    for (i=0;i<broken_list_size;i++) {
        ret = gnutls_mac_get_id( broken_list[i]);
        if (ret != GNUTLS_MAC_UNKNOWN) {
          out_priority[j++] = ret;
          continue;
        }
          
        _gnutls_debug_log( "MAC algorithm %s is not known\n", broken_list[i]);

        gnutls_free(darg);
        return GNUTLS_E_UNKNOWN_ALGORITHM;
    }
    out_priority[j] = 0;

    gnutls_free(darg);
    return 0;
}

/**
  * gnutls_certificate_type_convert_priority - Converts the priority on the certificate types supported by gnutls.
  * @out_priority: is a list of integers to copy priorities to
  * @out_priority_len: is the maximum number of integers the previous list can hold
  * @prio: is a separated list of algorithms
  * @sep: is the separator of the previous list, if zero comma is assumed
  *
  * Converts the priority on the Certificate types supported by gnutls to 
  * internal integer format
  * Priority is higher for elements specified before others.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * The supported types are: X.509, OPENPGP
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_certificate_type_convert_priority (int* out_priority, int out_priority_len, const char *prio, char sep)
{
    char *broken_list[_GNUTLS_MAX_PRIO];
    int broken_list_size, i, j, ret;
    char* darg;

    _GNUTLS_MAX_PRIO_CHECK(out_priority_len);
    
    darg = gnutls_strdup( prio);
    if (darg == NULL) {
      gnutls_assert();
      return GNUTLS_E_MEMORY_ERROR;
    }

    break_comma_list(darg, broken_list, &broken_list_size, out_priority_len-1, sep);

    j = 0;
    for (i=0;i<broken_list_size;i++) {
        ret = gnutls_certificate_type_get_id( broken_list[i]);
        if (ret != GNUTLS_CRT_UNKNOWN) {
          out_priority[j++] = ret;
          continue;
        }
        
        _gnutls_debug_log("Certificate type %s is not known\n", broken_list[i]);
        gnutls_free(darg);
        return GNUTLS_E_UNKNOWN_ALGORITHM;
    }
    out_priority[j] = 0;

        gnutls_free(darg);
    return 0;
}

/**
  * gnutls_compression_convert_priority - Converts the priority on the compression methods supported by gnutls.
  * @out_priority: is a list of integers to copy priorities to
  * @out_priority_len: is the maximum number of integers the previous list can hold
  * @prio: is a separated list of algorithms
  * @sep: is the separator of the previous list, if zero comma is assumed
  *
  * Converts the priority on the ciphers supported by gnutls to 
  * internal integer format
  * Priority is higher for elements specified before others.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * The supported methods are: NULL, DEFLATE, LZO
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_compression_convert_priority (int* out_priority, int out_priority_len, const char *prio, char sep)
{
    char *broken_list[_GNUTLS_MAX_PRIO];
    int broken_list_size, i, j;
    char* darg;
    int ret;

    _GNUTLS_MAX_PRIO_CHECK(out_priority_len);
    
    darg = gnutls_strdup( prio);
    if (darg == NULL) {
      gnutls_assert();
      return GNUTLS_E_MEMORY_ERROR;
    }

    break_comma_list(darg, broken_list, &broken_list_size, out_priority_len-1, sep);

    j = 0;
    for (i=0;i<broken_list_size;i++) {
        ret = gnutls_compression_get_id( broken_list[i]);
        if (ret != GNUTLS_COMP_UNKNOWN) {
          out_priority[j++] = ret;
          continue;
        }

        _gnutls_debug_log( "Compression algorithm %s is not known\n", broken_list[i]);
        gnutls_free(darg);
        return GNUTLS_E_UNKNOWN_COMPRESSION_ALGORITHM;
    }
    out_priority[j] = 0;

        gnutls_free(darg);
    return 0;
}

/**
  * gnutls_protocol_convert_priority - Converts the priority on the protocols supported by gnutls.
  * @out_priority: is a list of integers to copy priorities to
  * @out_priority_len: is the maximum number of integers the previous list can hold
  * @prio: is a separated list of algorithms
  * @sep: is the separator of the previous list, if zero comma is assumed
  *
  * Converts the priority on the protocols supported by gnutls to 
  * internal integer format
  * Priority is higher for elements specified before others.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * The supported protocols are: TLS1.0, TLS1.1, TLS1.2, SSL3.0
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_protocol_convert_priority (int* out_priority, int out_priority_len, const char *prio, char sep)
{
    char *broken_list[_GNUTLS_MAX_PRIO];
    int broken_list_size, i, j;
    char* darg;
    int ret;

    _GNUTLS_MAX_PRIO_CHECK(out_priority_len);
    
    darg = gnutls_strdup( prio);
    if (darg == NULL) {
      gnutls_assert();
      return GNUTLS_E_MEMORY_ERROR;
    }

    break_comma_list(darg, broken_list, &broken_list_size, out_priority_len-1, sep);

    j = 0;
    for (i=0;i<broken_list_size;i++) {
        ret = gnutls_compression_get_id( broken_list[i]);
        if (ret != GNUTLS_VERSION_UNKNOWN) {
          out_priority[j++] = ret;
          continue;
        }
        
        _gnutls_debug_log( "Protocol %s is not known\n", broken_list[i]);
        gnutls_free(darg);
        return GNUTLS_E_UNKNOWN_ALGORITHM;
    }
    out_priority[j] = 0;

        gnutls_free(darg);
    return 0;
}

/**
  * gnutls_kx_convert_priority - Converts the priority on the key exchange algorithms supported by gnutls.
  * @out_priority: is a list of integers to copy priorities to
  * @out_priority_len: is the maximum number of integers the previous list can hold
  * @prio: is a separated list of algorithms
  * @sep: is the separator of the previous list, if zero comma is assumed
  *
  * Converts the priority on the key exchange algorithms supported by gnutls to 
  * internal integer format
  * Priority is higher for elements specified before others.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * The supported algorithms are: RSA, DHE-DSS, DHE-RSA, ANON-DH, RSA-EXPORT,
  * SRP, SRP-DSS, SRP-RSA, PSK, DHE-PSK
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_kx_convert_priority (int* out_priority, int out_priority_len, const char *prio, char sep)
{
    char *broken_list[_GNUTLS_MAX_PRIO];
    int broken_list_size, i, j;
    char* darg;
    int ret;

    _GNUTLS_MAX_PRIO_CHECK(out_priority_len);
    
    darg = gnutls_strdup( prio);
    if (darg == NULL) {
      gnutls_assert();
      return GNUTLS_E_MEMORY_ERROR;
    }

    break_comma_list(darg, broken_list, &broken_list_size, out_priority_len-1, sep);

    j = 0;
    for (i=0;i<broken_list_size;i++) {
        ret = gnutls_kx_get_id( broken_list[i]);
        if (ret != GNUTLS_KX_UNKNOWN) {
          out_priority[j++] = ret;
          continue;
        }

        _gnutls_debug_log( "Key exchange algorithm %s is not known\n", broken_list[i]);
        gnutls_free(darg);
        return GNUTLS_E_UNKNOWN_ALGORITHM;
    }
    out_priority[j] = 0;

        gnutls_free(darg);
    return 0;
}

/**
  * gnutls_cipher_convert_priority - Converts the priority on the ciphers supported by gnutls.
  * @out_priority: is a list of integers to copy priorities to
  * @out_priority_len: is the maximum number of integers the previous list can hold
  * @prio: is a separated list of algorithms
  * @sep: is the separator of the previous list, if zero comma is assumed
  *
  * Converts the priority on the ciphers supported by gnutls to 
  * internal integer format.
  * Priority is higher for ciphers specified before others.
  * Note that the priority is set on the client. The server does
  * not use the algorithm's priority except for disabling
  * algorithms that were not specified.
  *
  * The supported algorithms are: NULL, ARCFOUR-128, ARCFOUR-40, 3DES-CBC,
  * AES-128-CBC, AES-256-CBC, CAMELIA-128-CBC, CAMELIA-256-CBC
  *
  * Returns 0 on success.
  *
  **/
int
gnutls_cipher_convert_priority (int* out_priority, int out_priority_len, const char *prio, char sep)
{
    char *broken_list[_GNUTLS_MAX_PRIO];
    int broken_list_size, i, j;
    char* darg;
    int ret;

    _GNUTLS_MAX_PRIO_CHECK(out_priority_len);
    
    darg = gnutls_strdup( prio);
    if (darg == NULL) {
      gnutls_assert();
      return GNUTLS_E_MEMORY_ERROR;
    }

    break_comma_list(darg, broken_list, &broken_list_size, out_priority_len-1, sep);

    j = 0;
    for (i=0;i<broken_list_size;i++) {
        ret = gnutls_cipher_get_id( broken_list[i]);
        if (ret != GNUTLS_CIPHER_UNKNOWN) {
          out_priority[j++] = ret;
          continue;
        }

        _gnutls_debug_log( "Cipher %s is not known\n", broken_list[i]);
        gnutls_free(darg);
        return GNUTLS_E_UNKNOWN_ALGORITHM;
    }
    out_priority[j] = 0;

        gnutls_free(darg);
    return 0;
}