2023-06-04 17:13:21 -07:00

172 lines
7.0 KiB
C

/* $OpenBSD: c_rle.c,v 1.11 2022/12/24 07:12:09 tb Exp $ */
/*
* ---------------------------------------------------------------------------
* Patches to this file were contributed by
* Ulf Moeller <ulf@openssl.org> and Bodo Moeller <bodo@openssl.org>.
* ---------------------------------------------------------------------------
* Copyright (c) 1999, 2011 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
* licensing@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.
*
* ---------------------------------------------------------------------------
* Parts of this file are derived from SSLeay code
* which is covered by the following Copyright and license:
* ---------------------------------------------------------------------------
* Copyright (c) 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/objects.h>
#include <openssl/comp.h>
#include "comp_local.h"
static int rle_compress_block(COMP_CTX *ctx, unsigned char *out,
unsigned int olen, unsigned char *in, unsigned int ilen);
static int rle_expand_block(COMP_CTX *ctx, unsigned char *out,
unsigned int olen, unsigned char *in, unsigned int ilen);
static COMP_METHOD rle_method = {
.type = NID_rle_compression,
.name = LN_rle_compression,
.compress = rle_compress_block,
.expand = rle_expand_block
};
COMP_METHOD *
COMP_rle(void)
{
return (&rle_method);
}
static int
rle_compress_block(COMP_CTX *ctx, unsigned char *out, unsigned int olen,
unsigned char *in, unsigned int ilen)
{
if (ilen == 0 || olen < (ilen - 1)) {
return (-1);
}
*(out++) = 0;
memcpy(out, in, ilen);
return (ilen + 1);
}
static int
rle_expand_block(COMP_CTX *ctx, unsigned char *out, unsigned int olen,
unsigned char *in, unsigned int ilen)
{
int i;
if (olen < (ilen - 1)) {
return (-1);
}
i= *(in++);
if (i == 0) {
memcpy(out, in, ilen - 1);
}
return (ilen - 1);
}