mirror of https://github.com/upx/upx.git
129 lines
4.0 KiB
C++
129 lines
4.0 KiB
C++
/* p_sys.cpp --
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This file is part of the UPX executable compressor.
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Copyright (C) 1996-2016 Markus Franz Xaver Johannes Oberhumer
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Copyright (C) 1996-2016 Laszlo Molnar
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All Rights Reserved.
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UPX and the UCL library are free software; you can redistribute them
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and/or modify them under the terms of the GNU General Public License as
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published by the Free Software Foundation; either version 2 of
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the License, or (at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; see the file COPYING.
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If not, write to the Free Software Foundation, Inc.,
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59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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Markus F.X.J. Oberhumer Laszlo Molnar
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<markus@oberhumer.com> <ezerotven+github@gmail.com>
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*/
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#include "conf.h"
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#include "file.h"
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#include "filter.h"
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#include "packer.h"
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#include "p_com.h"
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#include "p_sys.h"
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#include "linker.h"
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static const
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#include "stub/i086-dos16.sys.h"
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/*************************************************************************
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//
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**************************************************************************/
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bool PackSys::canPack()
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{
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unsigned char buf[128];
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fi->readx(buf, sizeof(buf));
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if (memcmp (buf,"\xff\xff\xff\xff",4) != 0)
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return false;
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if (!fn_has_ext(fi->getName(),"sys"))
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return false;
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checkAlreadyPacked(buf, sizeof(buf));
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if (file_size < 1024)
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throwCantPack("file is too small");
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if (file_size > 0x10000)
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throwCantPack("file is too big for dos/sys");
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return true;
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}
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/*************************************************************************
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//
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**************************************************************************/
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void PackSys::patchLoader(OutputFile *fo,
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upx_byte *loader, int lsize,
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unsigned calls)
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{
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const int e_len = getLoaderSectionStart("SYSCUTPO");
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const int d_len = lsize - e_len;
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assert(e_len > 0 && e_len < 128);
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assert(d_len > 0 && d_len < 256);
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if (ph.u_len + d_len + ph.overlap_overhead > 0xfffe)
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throwNotCompressible();
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// use some fields of the original file
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linker->defineSymbol("attribute", get_le16(ibuf + 4));
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linker->defineSymbol("interrupt", get_le16(ibuf + 8));
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unsigned copy_to = ph.u_len + d_len + ph.overlap_overhead;
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linker->defineSymbol("calltrick_calls", calls);
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linker->defineSymbol("copy_source", ph.c_len + lsize - 1);
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linker->defineSymbol("copy_destination", copy_to);
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linker->defineSymbol("neg_e_len", 0 - e_len);
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linker->defineSymbol("NRV2B160", ph.u_len + ph.overlap_overhead + 1);
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linker->defineSymbol("original_strategy", get_le16(ibuf + 6));
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relocateLoader();
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loader = getLoader();
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patchPackHeader(loader,e_len);
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// write loader + compressed file
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fo->write(loader,e_len); // entry
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fo->write(obuf,ph.c_len);
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fo->write(loader+e_len,d_len); // decompressor
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}
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void PackSys::buildLoader(const Filter *ft)
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{
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initLoader(stub_i086_dos16_sys, sizeof(stub_i086_dos16_sys));
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addLoader("SYSMAIN1",
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opt->cpu == opt->CPU_8086 ? "SYSI0861" : "SYSI2861",
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"SYSMAIN2",
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ph.first_offset_found == 1 ? "SYSSBBBP" : "",
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ft->id ? "SYSCALLT" : "",
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"SYSMAIN3,UPX1HEAD,SYSCUTPO,NRV2B160,NRVDDONE,NRVDECO1",
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ph.max_offset_found <= 0xd00 ? "NRVLED00" : "NRVGTD00",
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"NRVDECO2",
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NULL
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);
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if (ft->id)
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{
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assert(ft->calls > 0);
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addFilter16(ft->id);
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}
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addLoader("SYSMAIN5",
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opt->cpu == opt->CPU_8086 ? "SYSI0862" : "SYSI2862",
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"SYSJUMP1",
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NULL
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);
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}
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/* vim:set ts=4 sw=4 et: */
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