blob: b2da73add5a5477eed8139c55c385afdd044123a [file] [log] [blame]
/*
zip_algorithm_deflate.c -- deflate (de)compression routines
Copyright (C) 2017-2019 Dieter Baron and Thomas Klausner
This file is part of libzip, a library to manipulate ZIP archives.
The authors can be contacted at <libzip@nih.at>
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. The names of the authors may not be used to endorse or promote
products derived from this software without specific prior
written permission.
THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``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 AUTHORS 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.
*/
#include "zipint.h"
#include <limits.h>
#include <stdlib.h>
#include <zlib.h>
struct ctx {
zip_error_t *error;
bool compress;
int compression_flags;
bool end_of_input;
z_stream zstr;
};
static zip_uint64_t
maximum_compressed_size(zip_uint64_t uncompressed_size) {
/* max deflate size increase: size + ceil(size/16k)*5+6 */
zip_uint64_t compressed_size = uncompressed_size + (uncompressed_size + 16383) / 16384 * 5 + 6;
if (compressed_size < uncompressed_size) {
return ZIP_UINT64_MAX;
}
return compressed_size;
}
static void *
allocate(bool compress, int compression_flags, zip_error_t *error) {
struct ctx *ctx;
if ((ctx = (struct ctx *)malloc(sizeof(*ctx))) == NULL) {
zip_error_set(error, ZIP_ET_SYS, errno);
return NULL;
}
ctx->error = error;
ctx->compress = compress;
ctx->compression_flags = compression_flags;
if (ctx->compression_flags < 1 || ctx->compression_flags > 9) {
ctx->compression_flags = Z_BEST_COMPRESSION;
}
ctx->end_of_input = false;
ctx->zstr.zalloc = Z_NULL;
ctx->zstr.zfree = Z_NULL;
ctx->zstr.opaque = NULL;
return ctx;
}
static void *
compress_allocate(zip_uint16_t method, int compression_flags, zip_error_t *error) {
return allocate(true, compression_flags, error);
}
static void *
decompress_allocate(zip_uint16_t method, int compression_flags, zip_error_t *error) {
return allocate(false, compression_flags, error);
}
static void
deallocate(void *ud) {
struct ctx *ctx = (struct ctx *)ud;
free(ctx);
}
static zip_uint16_t
general_purpose_bit_flags(void *ud) {
struct ctx *ctx = (struct ctx *)ud;
if (!ctx->compress) {
return 0;
}
if (ctx->compression_flags < 3) {
return 2 << 1;
}
else if (ctx->compression_flags > 7) {
return 1 << 1;
}
return 0;
}
static bool
start(void *ud, zip_stat_t *st, zip_file_attributes_t *attributes) {
struct ctx *ctx = (struct ctx *)ud;
int ret;
ctx->zstr.avail_in = 0;
ctx->zstr.next_in = NULL;
ctx->zstr.avail_out = 0;
ctx->zstr.next_out = NULL;
if (ctx->compress) {
/* negative value to tell zlib not to write a header */
ret = deflateInit2(&ctx->zstr, ctx->compression_flags, Z_DEFLATED, -MAX_WBITS, MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);
}
else {
ret = inflateInit2(&ctx->zstr, -MAX_WBITS);
}
if (ret != Z_OK) {
zip_error_set(ctx->error, ZIP_ER_ZLIB, ret);
return false;
}
return true;
}
static bool
end(void *ud) {
struct ctx *ctx = (struct ctx *)ud;
int err;
if (ctx->compress) {
err = deflateEnd(&ctx->zstr);
}
else {
err = inflateEnd(&ctx->zstr);
}
if (err != Z_OK) {
zip_error_set(ctx->error, ZIP_ER_ZLIB, err);
return false;
}
return true;
}
static bool
input(void *ud, zip_uint8_t *data, zip_uint64_t length) {
struct ctx *ctx = (struct ctx *)ud;
if (length > UINT_MAX || ctx->zstr.avail_in > 0) {
zip_error_set(ctx->error, ZIP_ER_INVAL, 0);
return false;
}
ctx->zstr.avail_in = (uInt)length;
ctx->zstr.next_in = (Bytef *)data;
return true;
}
static void
end_of_input(void *ud) {
struct ctx *ctx = (struct ctx *)ud;
ctx->end_of_input = true;
}
static zip_compression_status_t
process(void *ud, zip_uint8_t *data, zip_uint64_t *length) {
struct ctx *ctx = (struct ctx *)ud;
int ret;
ctx->zstr.avail_out = (uInt)ZIP_MIN(UINT_MAX, *length);
ctx->zstr.next_out = (Bytef *)data;
if (ctx->compress) {
ret = deflate(&ctx->zstr, ctx->end_of_input ? Z_FINISH : 0);
}
else {
ret = inflate(&ctx->zstr, Z_SYNC_FLUSH);
}
*length = *length - ctx->zstr.avail_out;
switch (ret) {
case Z_OK:
return ZIP_COMPRESSION_OK;
case Z_STREAM_END:
return ZIP_COMPRESSION_END;
case Z_BUF_ERROR:
if (ctx->zstr.avail_in == 0) {
return ZIP_COMPRESSION_NEED_DATA;
}
/* fallthrough */
default:
zip_error_set(ctx->error, ZIP_ER_ZLIB, ret);
return ZIP_COMPRESSION_ERROR;
}
}
/* clang-format off */
zip_compression_algorithm_t zip_algorithm_deflate_compress = {
maximum_compressed_size,
compress_allocate,
deallocate,
general_purpose_bit_flags,
20,
start,
end,
input,
end_of_input,
process
};
zip_compression_algorithm_t zip_algorithm_deflate_decompress = {
maximum_compressed_size,
decompress_allocate,
deallocate,
general_purpose_bit_flags,
20,
start,
end,
input,
end_of_input,
process
};
/* clang-format on */