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/*
* Copyright (C) 2002, 2003, 2004, 2005, 2008, 2009, 2010 Free Software
* Foundation, Inc.
*
* Author: Nikos Mavrogiannopoulos
*
* 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
*
*/
#include "gnutls_int.h"
#include "gnutls_auth.h"
#include "gnutls_errors.h"
#include "gnutls_num.h"
#include <ext_server_name.h>
/*
* In case of a server: if a NAME_DNS extension type is received then
* it stores into the session the value of NAME_DNS. The server may
* use gnutls_ext_get_server_name(), in order to access it.
*
* In case of a client: If a proper NAME_DNS extension type is found
* in the session then it sends the extension to the peer.
*
*/
int
_gnutls_server_name_recv_params (gnutls_session_t session,
const opaque * data, size_t _data_size)
{
int i;
const unsigned char *p;
uint16_t len, type;
ssize_t data_size = _data_size;
int server_names = 0;
if (session->security_parameters.entity == GNUTLS_SERVER)
{
DECR_LENGTH_RET (data_size, 2, 0);
len = _gnutls_read_uint16 (data);
if (len != data_size)
{
/* This is unexpected packet length, but
* just ignore it, for now.
*/
gnutls_assert ();
return 0;
}
p = data + 2;
/* Count all server_names in the packet. */
while (data_size > 0)
{
DECR_LENGTH_RET (data_size, 1, 0);
p++;
DECR_LEN (data_size, 2);
len = _gnutls_read_uint16 (p);
p += 2;
if (len > 0)
{
DECR_LENGTH_RET (data_size, len, 0);
server_names++;
p += len;
}
else
_gnutls_handshake_log
("HSK[%p]: Received zero size server name (under attack?)\n",
session);
}
/* we cannot accept more server names.
*/
if (server_names > MAX_SERVER_NAME_EXTENSIONS)
{
_gnutls_handshake_log
("HSK[%p]: Too many server names received (under attack?)\n",
session);
server_names = MAX_SERVER_NAME_EXTENSIONS;
}
session->security_parameters.extensions.server_names_size =
server_names;
if (server_names == 0)
return 0; /* no names found */
p = data + 2;
for (i = 0; i < server_names; i++)
{
type = *p;
p++;
len = _gnutls_read_uint16 (p);
p += 2;
switch (type)
{
case 0: /* NAME_DNS */
if (len <= MAX_SERVER_NAME_SIZE)
{
memcpy (session->security_parameters.extensions.
server_names[i].name, p, len);
session->security_parameters.extensions.
server_names[i].name_length = len;
session->security_parameters.extensions.
server_names[i].type = GNUTLS_NAME_DNS;
break;
}
}
/* move to next record */
p += len;
}
}
return 0;
}
/* returns data_size or a negative number on failure
*/
int
_gnutls_server_name_send_params (gnutls_session_t session,
opaque * data, size_t _data_size)
{
uint16_t len;
opaque *p;
unsigned i;
ssize_t data_size = _data_size;
int total_size = 0;
/* this function sends the client extension data (dnsname)
*/
if (session->security_parameters.entity == GNUTLS_CLIENT)
{
if (session->security_parameters.extensions.server_names_size == 0)
return 0;
/* uint16_t
*/
total_size = 2;
for (i = 0;
i < session->security_parameters.extensions.server_names_size; i++)
{
/* count the total size
*/
len =
session->security_parameters.extensions.server_names[i].
name_length;
/* uint8_t + uint16_t + size
*/
total_size += 1 + 2 + len;
}
p = data;
/* UINT16: write total size of all names
*/
DECR_LENGTH_RET (data_size, 2, GNUTLS_E_SHORT_MEMORY_BUFFER);
_gnutls_write_uint16 (total_size - 2, p);
p += 2;
for (i = 0;
i < session->security_parameters.extensions.server_names_size; i++)
{
switch (session->security_parameters.extensions.
server_names[i].type)
{
case GNUTLS_NAME_DNS:
len =
session->security_parameters.extensions.
server_names[i].name_length;
if (len == 0)
break;
/* UINT8: type of this extension
* UINT16: size of the first name
* LEN: the actual server name.
*/
DECR_LENGTH_RET (data_size, len + 3,
GNUTLS_E_SHORT_MEMORY_BUFFER);
*p = 0; /* NAME_DNS type */
p++;
_gnutls_write_uint16 (len, p);
p += 2;
memcpy (p,
session->security_parameters.extensions.
server_names[i].name, len);
p += len;
break;
default:
gnutls_assert ();
return GNUTLS_E_INTERNAL_ERROR;
}
}
}
return total_size;
}
/**
* gnutls_server_name_get - Used to get the server name indicator send by a client
* @session: is a #gnutls_session_t structure.
* @data: will hold the data
* @data_length: will hold the data length. Must hold the maximum size of data.
* @type: will hold the server name indicator type
* @indx: is the index of the server_name
*
* This function will allow you to get the name indication (if any), a
* client has sent. The name indication may be any of the enumeration
* gnutls_server_name_type_t.
*
* If @type is GNUTLS_NAME_DNS, then this function is to be used by
* servers that support virtual hosting, and the data will be a null
* terminated UTF-8 string.
*
* If @data has not enough size to hold the server name
* GNUTLS_E_SHORT_MEMORY_BUFFER is returned, and @data_length will
* hold the required size.
*
* @index is used to retrieve more than one server names (if sent by
* the client). The first server name has an index of 0, the second 1
* and so on. If no name with the given index exists
* GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE is returned.
*
* Returns: On success, %GNUTLS_E_SUCCESS (zero) is returned,
* otherwise an error code is returned.
**/
int
gnutls_server_name_get (gnutls_session_t session, void *data,
size_t * data_length,
unsigned int *type, unsigned int indx)
{
char *_data = data;
if (session->security_parameters.entity == GNUTLS_CLIENT)
{
gnutls_assert ();
return GNUTLS_E_INVALID_REQUEST;
}
if (indx + 1 > session->security_parameters.extensions.server_names_size)
{
return GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE;
}
*type = session->security_parameters.extensions.server_names[indx].type;
if (*data_length > /* greater since we need one extra byte for the null */
session->security_parameters.extensions.server_names[indx].name_length)
{
*data_length =
session->security_parameters.extensions.server_names[indx].
name_length;
memcpy (data,
session->security_parameters.extensions.server_names[indx].name,
*data_length);
if (*type == GNUTLS_NAME_DNS) /* null terminate */
_data[(*data_length)] = 0;
}
else
{
*data_length =
session->security_parameters.extensions.server_names[indx].
name_length;
return GNUTLS_E_SHORT_MEMORY_BUFFER;
}
return 0;
}
/**
* gnutls_server_name_set - set a name indicator to be sent as an extension
* @session: is a #gnutls_session_t structure.
* @type: specifies the indicator type
* @name: is a string that contains the server name.
* @name_length: holds the length of name
*
* This function is to be used by clients that want to inform (via a
* TLS extension mechanism) the server of the name they connected to.
* This should be used by clients that connect to servers that do
* virtual hosting.
*
* The value of @name depends on the @type type. In case of
* %GNUTLS_NAME_DNS, an ASCII zero-terminated domain name string,
* without the trailing dot, is expected. IPv4 or IPv6 addresses are
* not permitted.
*
* Returns: On success, %GNUTLS_E_SUCCESS (zero) is returned,
* otherwise an error code is returned.
**/
int
gnutls_server_name_set (gnutls_session_t session,
gnutls_server_name_type_t type,
const void *name, size_t name_length)
{
int server_names;
if (session->security_parameters.entity == GNUTLS_SERVER)
{
gnutls_assert ();
return GNUTLS_E_INVALID_REQUEST;
}
if (name_length > MAX_SERVER_NAME_SIZE)
return GNUTLS_E_SHORT_MEMORY_BUFFER;
server_names =
session->security_parameters.extensions.server_names_size + 1;
if (server_names > MAX_SERVER_NAME_EXTENSIONS)
server_names = MAX_SERVER_NAME_EXTENSIONS;
session->security_parameters.extensions.server_names
[server_names - 1].type = type;
memcpy (session->security_parameters.extensions.
server_names[server_names - 1].name, name, name_length);
session->security_parameters.extensions.server_names[server_names -
1].name_length =
name_length;
session->security_parameters.extensions.server_names_size++;
return 0;
}
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