ssl/record/dtls1_bitmap.c - third_party/openssl - Git at Google

 /* ssl/record/dtls1_bitmap.c */
 /*
  * DTLS implementation written by Nagendra Modadugu
  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
  */
 /* ====================================================================
  * Copyright (c) 1998-2015 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).
  *
  */
 /* 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.]
  */

 #include "../ssl_locl.h"
 #include "record_locl.h"

 /* mod 128 saturating subtract of two 64-bit values in big-endian order */
 static int satsub64be(const unsigned char *v1, const unsigned char *v2)
 {
     int ret, sat, brw, i;

     if (sizeof(long) == 8)
         do {
             const union {
                 long one;
                 char little;
             } is_endian = {
                 1
             };
             long l;

             if (is_endian.little)
                 break;
             /* not reached on little-endians */
             /*
              * following test is redundant, because input is always aligned,
              * but I take no chances...
              */
             if (((size_t)v1 | (size_t)v2) & 0x7)
                 break;

             l = *((long *)v1);
             l -= *((long *)v2);
             if (l > 128)
                 return 128;
             else if (l < -128)
                 return -128;
             else
                 return (int)l;
         } while (0);

     ret = (int)v1[7] - (int)v2[7];
     sat = 0;
     brw = ret >> 8;             /* brw is either 0 or -1 */
     if (ret & 0x80) {
         for (i = 6; i >= 0; i--) {
             brw += (int)v1[i] - (int)v2[i];
             sat |= ~brw;
             brw >>= 8;
         }
     } else {
         for (i = 6; i >= 0; i--) {
             brw += (int)v1[i] - (int)v2[i];
             sat |= brw;
             brw >>= 8;
         }
     }
     brw <<= 8;                  /* brw is either 0 or -256 */

     if (sat & 0xff)
         return brw | 0x80;
     else
         return brw + (ret & 0xFF);
 }

 int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
 {
     int cmp;
     unsigned int shift;
     const unsigned char *seq = s->rlayer.read_sequence;

     cmp = satsub64be(seq, bitmap->max_seq_num);
     if (cmp > 0) {
         SSL3_RECORD_set_seq_num(RECORD_LAYER_get_rrec(&s->rlayer), seq);
         return 1;               /* this record in new */
     }
     shift = -cmp;
     if (shift >= sizeof(bitmap->map) * 8)
         return 0;               /* stale, outside the window */
     else if (bitmap->map & (1UL << shift))
         return 0;               /* record previously received */

     SSL3_RECORD_set_seq_num(RECORD_LAYER_get_rrec(&s->rlayer), seq);
     return 1;
 }

 void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
 {
     int cmp;
     unsigned int shift;
     const unsigned char *seq = RECORD_LAYER_get_read_sequence(&s->rlayer);

     cmp = satsub64be(seq, bitmap->max_seq_num);
     if (cmp > 0) {
         shift = cmp;
         if (shift < sizeof(bitmap->map) * 8)
             bitmap->map <<= shift, bitmap->map |= 1UL;
         else
             bitmap->map = 1UL;
         memcpy(bitmap->max_seq_num, seq, SEQ_NUM_SIZE);
     } else {
         shift = -cmp;
         if (shift < sizeof(bitmap->map) * 8)
             bitmap->map |= 1UL << shift;
     }
 }
	/* ssl/record/dtls1_bitmap.c */
	/*
	* DTLS implementation written by Nagendra Modadugu
	* (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
	*/
	/* ====================================================================
	* Copyright (c) 1998-2015 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).
	*
	*/
	/* 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.]
	*/

	#include "../ssl_locl.h"
	#include "record_locl.h"

	/* mod 128 saturating subtract of two 64-bit values in big-endian order */
	static int satsub64be(const unsigned char v1, const unsigned char v2)
	{
	int ret, sat, brw, i;

	if (sizeof(long) == 8)
	do {
	const union {
	long one;
	char little;
	} is_endian = {
	1
	};
	long l;

	if (is_endian.little)
	break;
	/* not reached on little-endians */
	/*
	* following test is redundant, because input is always aligned,
	* but I take no chances...
	*/
	if (((size_t)v1 \| (size_t)v2) & 0x7)
	break;

	l = ((long )v1);
	l -= ((long )v2);
	if (l > 128)
	return 128;
	else if (l < -128)
	return -128;
	else
	return (int)l;
	} while (0);

	ret = (int)v1[7] - (int)v2[7];
	sat = 0;
	brw = ret >> 8; /* brw is either 0 or -1 */
	if (ret & 0x80) {
	for (i = 6; i >= 0; i--) {
	brw += (int)v1[i] - (int)v2[i];
	sat \|= ~brw;
	brw >>= 8;
	}
	} else {
	for (i = 6; i >= 0; i--) {
	brw += (int)v1[i] - (int)v2[i];
	sat \|= brw;
	brw >>= 8;
	}
	}
	brw <<= 8; /* brw is either 0 or -256 */

	if (sat & 0xff)
	return brw \| 0x80;
	else
	return brw + (ret & 0xFF);
	}

	int dtls1_record_replay_check(SSL s, DTLS1_BITMAP bitmap)
	{
	int cmp;
	unsigned int shift;
	const unsigned char *seq = s->rlayer.read_sequence;

	cmp = satsub64be(seq, bitmap->max_seq_num);
	if (cmp > 0) {
	SSL3_RECORD_set_seq_num(RECORD_LAYER_get_rrec(&s->rlayer), seq);
	return 1; /* this record in new */
	}
	shift = -cmp;
	if (shift >= sizeof(bitmap->map) * 8)
	return 0; /* stale, outside the window */
	else if (bitmap->map & (1UL << shift))
	return 0; /* record previously received */

	SSL3_RECORD_set_seq_num(RECORD_LAYER_get_rrec(&s->rlayer), seq);
	return 1;
	}

	void dtls1_record_bitmap_update(SSL s, DTLS1_BITMAP bitmap)
	{
	int cmp;
	unsigned int shift;
	const unsigned char *seq = RECORD_LAYER_get_read_sequence(&s->rlayer);

	cmp = satsub64be(seq, bitmap->max_seq_num);
	if (cmp > 0) {
	shift = cmp;
	if (shift < sizeof(bitmap->map) * 8)
	bitmap->map <<= shift, bitmap->map \|= 1UL;
	else
	bitmap->map = 1UL;
	memcpy(bitmap->max_seq_num, seq, SEQ_NUM_SIZE);
	} else {
	shift = -cmp;
	if (shift < sizeof(bitmap->map) * 8)
	bitmap->map \|= 1UL << shift;
	}
	}