library/ssl_tls13_generic.c

/*
 *  TLS 1.3 functionality shared between client and server
 *
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

#include "common.h"

#if defined(MBEDTLS_SSL_TLS_C)

#if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)

#include "mbedtls/error.h"

#include "ssl_misc.h"

int mbedtls_ssl_start_handshake_msg( mbedtls_ssl_context *ssl,
                                     unsigned hs_type,
                                     unsigned char **buf,
                                     size_t *buflen )
{
    *buf = ssl->out_msg + 4;
    *buflen = MBEDTLS_SSL_OUT_CONTENT_LEN - 4;

    ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
    ssl->out_msg[0]  = hs_type;

    return( 0 );
}

int mbedtls_ssl_finish_handshake_msg( mbedtls_ssl_context *ssl,
                                      size_t buf_len,
                                      size_t msg_len )
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    ((void) buf_len);

    ssl->out_msglen = msg_len + 4;
    MBEDTLS_SSL_PROC_CHK( mbedtls_ssl_write_handshake_msg_ext, ( ssl, 0 ) );

cleanup:
    return( ret );
}

void mbedtls_ssl_add_hs_hdr_to_checksum( mbedtls_ssl_context *ssl,
                                         unsigned hs_type,
                                         size_t total_hs_len )
{
    unsigned char hs_hdr[4];

    /* Build HS header for checksum update. */
    hs_hdr[0] = hs_type;
    hs_hdr[1] = (unsigned char)( total_hs_len >> 16 );
    hs_hdr[2] = (unsigned char)( total_hs_len >>  8 );
    hs_hdr[3] = (unsigned char)( total_hs_len >>  0 );

    ssl->handshake->update_checksum( ssl, hs_hdr, sizeof( hs_hdr ) );
}

#endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */

#endif /* MBEDTLS_SSL_TLS_C */