/* $OpenBSD: t1_reneg.c,v 1.15 2017/02/07 02:08:38 beck Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */
/* ====================================================================
 * Copyright (c) 1998-2009 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    openssl-core@openssl.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */

#include <stdio.h>

#include <openssl/objects.h>

#include "ssl_locl.h"
#include "bytestring.h"

/* Add the client's renegotiation binding */
int
ssl_add_clienthello_renegotiate_ext(SSL *s, unsigned char *p, int *len,
    int maxlen)
{
	if (p) {
		if ((S3I(s)->previous_client_finished_len + 1) > maxlen) {
			SSLerror(s, SSL_R_RENEGOTIATE_EXT_TOO_LONG);
			return 0;
		}

		/* Length byte */
		*p = S3I(s)->previous_client_finished_len;
		p++;

		memcpy(p, S3I(s)->previous_client_finished,
		    S3I(s)->previous_client_finished_len);

	}

	*len = S3I(s)->previous_client_finished_len + 1;

	return 1;
}

/* Parse the client's renegotiation binding and abort if it's not
   right */
int
ssl_parse_clienthello_renegotiate_ext(SSL *s, const unsigned char *d, int len,
    int *al)
{
	CBS cbs, reneg;

	if (len < 0) {
		SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
		*al = SSL_AD_ILLEGAL_PARAMETER;
		return 0;
	}

	CBS_init(&cbs, d, len);
	if (!CBS_get_u8_length_prefixed(&cbs, &reneg) ||
	    /* Consistency check */
	    CBS_len(&cbs) != 0) {
		SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
		*al = SSL_AD_ILLEGAL_PARAMETER;
		return 0;
	}

	/* Check that the extension matches */
	if (CBS_len(&reneg) != S3I(s)->previous_client_finished_len) {
		SSLerror(s, SSL_R_RENEGOTIATION_MISMATCH);
		*al = SSL_AD_HANDSHAKE_FAILURE;
		return 0;
	}

	if (!CBS_mem_equal(&reneg, S3I(s)->previous_client_finished,
	    S3I(s)->previous_client_finished_len)) {
		SSLerror(s, SSL_R_RENEGOTIATION_MISMATCH);
		*al = SSL_AD_HANDSHAKE_FAILURE;
		return 0;
	}

	S3I(s)->send_connection_binding = 1;

	return 1;
}

/* Add the server's renegotiation binding */
int
ssl_add_serverhello_renegotiate_ext(SSL *s, unsigned char *p, int *len,
    int maxlen)
{
	if (p) {
		if ((S3I(s)->previous_client_finished_len +
		    S3I(s)->previous_server_finished_len + 1) > maxlen) {
			SSLerror(s, SSL_R_RENEGOTIATE_EXT_TOO_LONG);
			return 0;
		}

		/* Length byte */
		*p = S3I(s)->previous_client_finished_len +
		    S3I(s)->previous_server_finished_len;
		p++;

		memcpy(p, S3I(s)->previous_client_finished,
		    S3I(s)->previous_client_finished_len);
		p += S3I(s)->previous_client_finished_len;

		memcpy(p, S3I(s)->previous_server_finished,
		    S3I(s)->previous_server_finished_len);

	}

	*len = S3I(s)->previous_client_finished_len +
	    S3I(s)->previous_server_finished_len + 1;

	return 1;
}

/* Parse the server's renegotiation binding and abort if it's not
   right */
int
ssl_parse_serverhello_renegotiate_ext(SSL *s, const unsigned char *d, int len, int *al)
{
	CBS cbs, reneg, previous_client, previous_server;
	int expected_len = S3I(s)->previous_client_finished_len +
	    S3I(s)->previous_server_finished_len;

	/* Check for logic errors */
	OPENSSL_assert(!expected_len || S3I(s)->previous_client_finished_len);
	OPENSSL_assert(!expected_len || S3I(s)->previous_server_finished_len);

	if (len < 0) {
		SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
		*al = SSL_AD_ILLEGAL_PARAMETER;
		return 0;
	}

	CBS_init(&cbs, d, len);

	if (!CBS_get_u8_length_prefixed(&cbs, &reneg) ||
	    /* Consistency check */
	    CBS_len(&cbs) != 0) {
		SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
		*al = SSL_AD_ILLEGAL_PARAMETER;
		return 0;
	}

	/* Check that the extension matches */
	if (CBS_len(&reneg) != expected_len ||
	    !CBS_get_bytes(&reneg, &previous_client,
	    S3I(s)->previous_client_finished_len) ||
	    !CBS_get_bytes(&reneg, &previous_server,
	    S3I(s)->previous_server_finished_len) ||
	    CBS_len(&reneg) != 0) {
		SSLerror(s, SSL_R_RENEGOTIATION_MISMATCH);
		*al = SSL_AD_HANDSHAKE_FAILURE;
		return 0;
	}

	if (!CBS_mem_equal(&previous_client, S3I(s)->previous_client_finished,
	    CBS_len(&previous_client))) {
		SSLerror(s, SSL_R_RENEGOTIATION_MISMATCH);
		*al = SSL_AD_HANDSHAKE_FAILURE;
		return 0;
	}
	if (!CBS_mem_equal(&previous_server, S3I(s)->previous_server_finished,
	    CBS_len(&previous_server))) {
		SSLerror(s, SSL_R_RENEGOTIATION_MISMATCH);
		*al = SSL_AD_ILLEGAL_PARAMETER;
		return 0;
	}

	S3I(s)->send_connection_binding = 1;

	return 1;
}
