mirror of
https://github.com/upx/upx
synced 2025-09-28 19:06:07 +08:00
123 lines
4.3 KiB
C++
123 lines
4.3 KiB
C++
/* p_sys.cpp -- dos/sys executable format
|
|
|
|
This file is part of the UPX executable compressor.
|
|
|
|
Copyright (C) 1996-2023 Markus Franz Xaver Johannes Oberhumer
|
|
Copyright (C) 1996-2023 Laszlo Molnar
|
|
All Rights Reserved.
|
|
|
|
UPX and the UCL library are free software; you can redistribute them
|
|
and/or modify them 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.
|
|
|
|
This program 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; see the file COPYING.
|
|
If not, write to the Free Software Foundation, Inc.,
|
|
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
Markus F.X.J. Oberhumer Laszlo Molnar
|
|
<markus@oberhumer.com> <ezerotven+github@gmail.com>
|
|
*/
|
|
|
|
#include "conf.h"
|
|
#include "file.h"
|
|
#include "filter.h"
|
|
#include "packer.h"
|
|
#include "p_com.h"
|
|
#include "p_sys.h"
|
|
#include "linker.h"
|
|
|
|
static const CLANG_FORMAT_DUMMY_STATEMENT
|
|
#include "stub/i086-dos16.sys.h"
|
|
|
|
/*************************************************************************
|
|
//
|
|
**************************************************************************/
|
|
|
|
tribool PackSys::canPack() {
|
|
byte buf[128];
|
|
|
|
fi->readx(buf, sizeof(buf));
|
|
if (memcmp(buf, "\xff\xff\xff\xff", 4) != 0)
|
|
return false;
|
|
if (!fn_has_ext(fi->getName(), "sys")) // query file name
|
|
return false;
|
|
checkAlreadyPacked(buf, sizeof(buf));
|
|
if (file_size < 1024)
|
|
throwCantPack("file is too small for dos/sys");
|
|
if (file_size > 0x10000)
|
|
throwCantPack("file is too large for dos/sys");
|
|
return true;
|
|
}
|
|
|
|
/*************************************************************************
|
|
//
|
|
**************************************************************************/
|
|
|
|
void PackSys::buildLoader(const Filter *ft) {
|
|
initLoader(stub_i086_dos16_sys, sizeof(stub_i086_dos16_sys));
|
|
// clang-format off
|
|
addLoader("SYSMAIN1",
|
|
opt->cpu_x86 == opt->CPU_8086 ? "SYSI0861" : "SYSI2861",
|
|
"SYSMAIN2",
|
|
ph.first_offset_found == 1 ? "SYSSBBBP" : "",
|
|
ft->id ? "SYSCALLT" : "",
|
|
"SYSMAIN3,UPX1HEAD,SYSCUTPO,NRV2B160,NRVDDONE,NRVDECO1",
|
|
ph.max_offset_found <= 0xd00 ? "NRVLED00" : "NRVGTD00",
|
|
"NRVDECO2");
|
|
// clang-format on
|
|
if (ft->id) {
|
|
assert(ft->calls > 0);
|
|
addFilter16(ft->id);
|
|
}
|
|
// clang-format off
|
|
addLoader("SYSMAIN5",
|
|
opt->cpu_x86 == opt->CPU_8086 ? "SYSI0862" : "SYSI2862",
|
|
"SYSJUMP1");
|
|
// clang-format on
|
|
}
|
|
|
|
void PackSys::patchLoader(OutputFile *fo, byte *loader, int lsize, unsigned calls) {
|
|
const int e_len = getLoaderSectionStart("SYSCUTPO");
|
|
const int d_len = lsize - e_len;
|
|
assert(e_len > 0 && e_len < 128);
|
|
assert(d_len > 0 && d_len < 256);
|
|
|
|
if (ph.u_len + d_len + ph.overlap_overhead > 0xfffe)
|
|
throwNotCompressible();
|
|
|
|
// use some fields of the original file
|
|
linker->defineSymbol("attribute", get_le16(ibuf + 4));
|
|
linker->defineSymbol("interrupt", get_le16(ibuf + 8));
|
|
|
|
unsigned copy_to = ph.u_len + d_len + ph.overlap_overhead;
|
|
|
|
linker->defineSymbol("calltrick_calls", calls);
|
|
linker->defineSymbol("copy_source", ph.c_len + lsize - 1);
|
|
linker->defineSymbol("copy_destination", copy_to);
|
|
linker->defineSymbol("neg_e_len", 0 - e_len);
|
|
linker->defineSymbol("NRV2B160", ph.u_len + ph.overlap_overhead + 1);
|
|
linker->defineSymbol("original_strategy", get_le16(ibuf + 6));
|
|
|
|
relocateLoader();
|
|
loader = getLoader();
|
|
|
|
// some day we could use the relocation stuff for patchPackHeader too..
|
|
patchPackHeader(loader, e_len);
|
|
// write loader + compressed file
|
|
fo->write(loader, e_len); // entry
|
|
fo->write(obuf, ph.c_len); // compressed
|
|
fo->write(loader + e_len, d_len); // decompressor
|
|
NO_printf("%-13s: entry : %8u bytes\n", getName(), e_len);
|
|
NO_printf("%-13s: compressed : %8u bytes\n", getName(), ph.c_len);
|
|
NO_printf("%-13s: decompressor : %8u bytes\n", getName(), d_len);
|
|
}
|
|
|
|
/* vim:set ts=4 sw=4 et: */
|