2021-11-30 14:51:24 +01:00

199 lines
5.5 KiB
C

/* compress.c
*
* Copyright (C) 2006-2020 wolfSSL Inc.
*
* This file is part of wolfSSL.
*
* wolfSSL is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* wolfSSL 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <wolfssl/wolfcrypt/settings.h>
#ifdef HAVE_LIBZ
#include <wolfssl/wolfcrypt/compress.h>
#include <wolfssl/wolfcrypt/error-crypt.h>
#include <wolfssl/wolfcrypt/logging.h>
#ifdef NO_INLINE
#include <wolfssl/wolfcrypt/misc.h>
#else
#define WOLFSSL_MISC_INCLUDED
#include <wolfcrypt/src/misc.c>
#endif
#include <zlib.h>
/* alloc user allocs to work with zlib */
static void* myAlloc(void* opaque, unsigned int item, unsigned int size)
{
(void)opaque;
return XMALLOC(item * size, opaque, DYNAMIC_TYPE_LIBZ);
}
static void myFree(void* opaque, void* memory)
{
(void)opaque;
XFREE(memory, opaque, DYNAMIC_TYPE_LIBZ);
}
#ifdef HAVE_MCAPI
#define DEFLATE_DEFAULT_WINDOWBITS 11
#define DEFLATE_DEFAULT_MEMLEVEL 1
#else
#define DEFLATE_DEFAULT_WINDOWBITS 15
#define DEFLATE_DEFAULT_MEMLEVEL 8
#endif
/*
* out - pointer to destination buffer
* outSz - size of destination buffer
* in - pointer to source buffer to compress
* inSz - size of source to compress
* flags - flags to control how compress operates
*
* return:
* negative - error code
* positive - bytes stored in out buffer
*
* Note, the output buffer still needs to be larger than the input buffer.
* The right chunk of data won't compress at all, and the lookup table will
* add to the size of the output. The libz code says the compressed
* buffer should be srcSz + 0.1% + 12.
*/
int wc_Compress_ex(byte* out, word32 outSz, const byte* in, word32 inSz,
word32 flags, word32 windowBits)
{
z_stream stream;
int result = 0;
stream.next_in = (Bytef*)in;
stream.avail_in = (uInt)inSz;
#ifdef MAXSEG_64K
/* Check for source > 64K on 16-bit machine: */
if ((uLong)stream.avail_in != inSz) return COMPRESS_INIT_E;
#endif
stream.next_out = out;
stream.avail_out = (uInt)outSz;
if ((uLong)stream.avail_out != outSz) return COMPRESS_INIT_E;
stream.zalloc = (alloc_func)myAlloc;
stream.zfree = (free_func)myFree;
stream.opaque = (voidpf)0;
if (deflateInit2(&stream, Z_DEFAULT_COMPRESSION, Z_DEFLATED,
DEFLATE_DEFAULT_WINDOWBITS | windowBits,
DEFLATE_DEFAULT_MEMLEVEL,
flags ? Z_FIXED : Z_DEFAULT_STRATEGY) != Z_OK)
return COMPRESS_INIT_E;
if (deflate(&stream, Z_FINISH) != Z_STREAM_END) {
deflateEnd(&stream);
return COMPRESS_E;
}
result = (int)stream.total_out;
if (deflateEnd(&stream) != Z_OK)
result = COMPRESS_E;
return result;
}
int wc_Compress(byte* out, word32 outSz, const byte* in, word32 inSz, word32 flags)
{
return wc_Compress_ex(out, outSz, in, inSz, flags, 0);
}
/* windowBits:
* deflateInit() and inflateInit(), as well as deflateInit2() and inflateInit2()
with windowBits in 0..15 all process zlib-wrapped deflate data.
(See RFC 1950 and RFC 1951.)
* deflateInit2() and inflateInit2() with negative windowBits in -1..-15 process
raw deflate data with no header or trailer.
* deflateInit2() and inflateInit2() with windowBits in 16..31, i.e. 16
added to 0..15, process gzip-wrapped deflate data (RFC 1952).
* inflateInit2() with windowBits in 32..47 (32 added to 0..15) will
automatically detect either a gzip or zlib header (but not raw deflate
data), and decompress accordingly.
*/
int wc_DeCompress_ex(byte* out, word32 outSz, const byte* in, word32 inSz,
int windowBits)
/*
* out - pointer to destination buffer
* outSz - size of destination buffer
* in - pointer to source buffer to compress
* inSz - size of source to compress
* windowBits - flags to control how decompress operates
*
* return:
* negative - error code
* positive - bytes stored in out buffer
*/
{
z_stream stream;
int result = 0;
stream.next_in = (Bytef*)in;
stream.avail_in = (uInt)inSz;
/* Check for source > 64K on 16-bit machine: */
if ((uLong)stream.avail_in != inSz) return DECOMPRESS_INIT_E;
stream.next_out = out;
stream.avail_out = (uInt)outSz;
if ((uLong)stream.avail_out != outSz) return DECOMPRESS_INIT_E;
stream.zalloc = (alloc_func)myAlloc;
stream.zfree = (free_func)myFree;
stream.opaque = (voidpf)0;
if (inflateInit2(&stream, DEFLATE_DEFAULT_WINDOWBITS | windowBits) != Z_OK)
return DECOMPRESS_INIT_E;
result = inflate(&stream, Z_FINISH);
if (result != Z_STREAM_END) {
inflateEnd(&stream);
return DECOMPRESS_E;
}
result = (int)stream.total_out;
if (inflateEnd(&stream) != Z_OK)
result = DECOMPRESS_E;
return result;
}
int wc_DeCompress(byte* out, word32 outSz, const byte* in, word32 inSz)
{
return wc_DeCompress_ex(out, outSz, in, inSz, 0);
}
#endif /* HAVE_LIBZ */