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/*
* Copyright (C) 2017 Red Hat, Inc.
*
* Author: Nikos Mavrogiannopoulos
*
* This file is part of GnuTLS.
*
* The GnuTLS 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 program. If not, see <http://www.gnu.org/licenses/>
*
*/
/* Functions that relate to the TLS handshake procedure.
*/
#include "gnutls_int.h"
#include "errors.h"
#include "dh.h"
#include "debug.h"
#include "algorithms.h"
#include "cipher.h"
#include "buffers.h"
#include "mbuffers.h"
#include "kx.h"
#include "handshake.h"
#include "num.h"
#include "hash_int.h"
#include "db.h"
#include "hello_ext.h"
#include "supplemental.h"
#include "auth.h"
#include "sslv2_compat.h"
#include <auth/cert.h>
#include "constate.h"
#include <record.h>
#include <state.h>
#include <random.h>
#include <dtls.h>
#include "secrets.h"
#include "tls13/encrypted_extensions.h"
#include "tls13/certificate_request.h"
#include "tls13/certificate_verify.h"
#include "tls13/certificate.h"
#include "tls13/finished.h"
#include "tls13/session_ticket.h"
static int generate_hs_traffic_keys(gnutls_session_t session);
static int generate_ap_traffic_keys(gnutls_session_t session);
/*
* _gnutls13_handshake_client
* This function performs the client side of the handshake of the TLS/SSL protocol.
*/
int _gnutls13_handshake_client(gnutls_session_t session)
{
int ret = 0;
switch (STATE) {
case STATE100:
ret =
generate_hs_traffic_keys(session);
STATE = STATE100;
IMED_RET("generate session keys", ret, 0);
/* fall through */
case STATE101:
ret = _gnutls13_recv_encrypted_extensions(session);
STATE = STATE101;
IMED_RET("recv encrypted extensions", ret, 0);
/* fall through */
case STATE102:
ret = _gnutls13_recv_certificate_request(session);
STATE = STATE102;
IMED_RET("recv certificate request", ret, 0);
/* fall through */
case STATE103:
ret = _gnutls13_recv_certificate(session);
STATE = STATE103;
IMED_RET("recv certificate", ret, 0);
/* fall through */
case STATE104:
ret = _gnutls13_recv_certificate_verify(session);
STATE = STATE104;
IMED_RET("recv server certificate verify", ret, 0);
/* fall through */
case STATE105:
ret = _gnutls_run_verify_callback(session, GNUTLS_CLIENT);
STATE = STATE105;
if (ret < 0)
return gnutls_assert_val(ret);
FALLTHROUGH;
case STATE106:
ret = _gnutls13_recv_finished(session);
STATE = STATE106;
IMED_RET("recv finished", ret, 0);
/* fall through */
case STATE107:
ret = _gnutls13_send_certificate(session);
STATE = STATE107;
IMED_RET("send certificate", ret, 0);
/* fall through */
case STATE108:
ret = _gnutls13_send_certificate_verify(session);
STATE = STATE108;
IMED_RET("send certificate verify", ret, 0);
/* fall through */
case STATE109:
ret = _gnutls13_send_finished(session, AGAIN(STATE109));
STATE = STATE109;
IMED_RET("send finished", ret, 0);
/* fall through */
case STATE110:
ret =
generate_ap_traffic_keys(session);
STATE = STATE110;
IMED_RET("generate app keys", ret, 0);
STATE = STATE0;
break;
default:
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
}
/* explicitly reset any false start flags */
session->internals.recv_state = RECV_STATE_0;
session->internals.initial_negotiation_completed = 1;
return 0;
}
static int generate_ap_traffic_keys(gnutls_session_t session)
{
int ret;
uint8_t zero[MAX_HASH_SIZE];
ret = _tls13_derive_secret(session, DERIVED_LABEL, sizeof(DERIVED_LABEL)-1,
NULL, 0, session->key.temp_secret);
if (ret < 0)
return gnutls_assert_val(ret);
memset(zero, 0, session->security_parameters.prf->output_size);
ret = _tls13_update_secret(session, zero, session->security_parameters.prf->output_size);
if (ret < 0)
return gnutls_assert_val(ret);
_gnutls_epoch_bump(session);
ret = _gnutls_epoch_dup(session);
if (ret < 0)
return gnutls_assert_val(ret);
ret = _tls13_connection_state_init(session, STAGE_APP);
if (ret < 0)
return gnutls_assert_val(ret);
return 0;
}
static int generate_hs_traffic_keys(gnutls_session_t session)
{
int ret;
if (unlikely(session->key.key.size == 0))
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
ret = _tls13_update_secret(session, session->key.key.data, session->key.key.size);
if (ret < 0) {
gnutls_assert();
return ret;
}
ret = _tls13_connection_state_init(session, STAGE_HS);
if (ret < 0) {
gnutls_assert();
return ret;
}
return 0;
}
/*
* _gnutls13_handshake_server
* This function does the server stuff of the handshake protocol.
*/
int _gnutls13_handshake_server(gnutls_session_t session)
{
int ret = 0;
switch (STATE) {
case STATE100:
ret =
generate_hs_traffic_keys(session);
STATE = STATE100;
IMED_RET("generate session keys", ret, 0);
/* fall through */
case STATE101:
abort();
STATE = STATE101;
IMED_RET("send encrypted extensions", ret, 0);
/* fall through */
case STATE102:
abort();
STATE = STATE102;
IMED_RET("send certificate request", ret, 0);
/* fall through */
case STATE103:
abort();
STATE = STATE103;
IMED_RET("send certificate", ret, 0);
/* fall through */
case STATE104:
abort();
STATE = STATE104;
IMED_RET("send certificate verify", ret, 0);
/* fall through */
case STATE105:
abort();
STATE = STATE105;
IMED_RET("send finished", ret, 0);
/* fall through */
case STATE106:
abort();
STATE = STATE106;
IMED_RET("recv certificate", ret, 0);
/* fall through */
case STATE107:
abort();
STATE = STATE107;
IMED_RET("recv certificate verify", ret, 0);
/* fall through */
case STATE108:
ret = _gnutls_run_verify_callback(session, GNUTLS_SERVER);
STATE = STATE108;
if (ret < 0)
return gnutls_assert_val(ret);
/* fall through */
case STATE109:
abort();
STATE = STATE109;
IMED_RET("recv finished", ret, 0);
/* fall through */
STATE = STATE0;
break;
default:
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
}
return 0;
}
int
_gnutls13_recv_async_handshake(gnutls_session_t session, gnutls_buffer_st *buf)
{
uint8_t type;
int ret;
size_t handshake_header_size = HANDSHAKE_HEADER_SIZE(session);
size_t length;
if (buf->length < handshake_header_size) {
gnutls_assert();
return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
}
if (session->security_parameters.entity == GNUTLS_CLIENT) {
ret = _gnutls_buffer_pop_prefix8(buf, &type, 0);
if (ret < 0)
return gnutls_assert_val(ret);
ret = _gnutls_buffer_pop_prefix24(buf, &length, 1);
if (ret < 0)
return gnutls_assert_val(ret);
switch(type) {
case GNUTLS_HANDSHAKE_NEW_SESSION_TICKET:
ret = _gnutls13_recv_session_ticket(session, buf);
if (ret < 0)
return gnutls_assert_val(ret);
break;
default:
gnutls_assert();
return GNUTLS_E_UNEXPECTED_PACKET;
}
} else {
gnutls_assert();
return GNUTLS_E_UNEXPECTED_PACKET;
}
return 0;
}
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