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packer.cpp
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/* packer.cpp --
This file is part of the UPX executable compressor.
Copyright (C) 1996-2020 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1996-2020 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 "packer.h"
#include "filter.h"
#include "linker.h"
#include "ui.h"
/*************************************************************************
//
**************************************************************************/
Packer::Packer(InputFile *f) :
bele(NULL),
fi(f), file_size(-1), ph_format(-1), ph_version(-1),
uip(NULL), linker(NULL),
last_patch(NULL), last_patch_len(0), last_patch_off(0)
{
if (fi != NULL)
file_size = fi->st_size();
uip = new UiPacker(this);
mem_clear(&ph, sizeof(ph));
}
Packer::~Packer()
{
delete uip; uip = NULL;
delete linker; linker = NULL;
}
// for PackMaster
void Packer::assertPacker() const
{
assert(getFormat() > 0);
assert(getFormat() < 255);
assert(getVersion() >= 11);
assert(getVersion() <= 14);
assert(strlen(getName()) <= 15);
// info: 36 is the limit for show_all_packers() in help.cpp
assert(strlen(getFullName(opt)) <= 32);
assert(strlen(getFullName(NULL)) <= 32);
if (bele == NULL) fprintf(stderr, "%s\n", getName());
assert(bele != NULL);
if (getFormat() != UPX_F_MACH_FAT) // macho/fat is multiarch
{
const N_BELE_RTP::AbstractPolicy *format_bele;
if (getFormat() < 128)
format_bele = &N_BELE_RTP::le_policy;
else
format_bele = &N_BELE_RTP::be_policy;
if (bele != format_bele) fprintf(stderr, "%s\n", getName());
assert(bele == format_bele);
}
#if 1
Linker *l = newLinker();
if (bele != l->bele) fprintf(stderr, "%s\n", getName());
assert(bele == l->bele);
delete l;
#endif
}
/*************************************************************************
// public entries called from class PackMaster
**************************************************************************/
void Packer::doPack(OutputFile *fo)
{
uip->uiPackStart(fo);
pack(fo);
uip->uiPackEnd(fo);
}
void Packer::doUnpack(OutputFile *fo)
{
uip->uiUnpackStart(fo);
unpack(fo);
uip->uiUnpackEnd(fo);
}
void Packer::doTest()
{
uip->uiTestStart();
test();
uip->uiTestEnd();
}
void Packer::doList()
{
uip->uiListStart();
list();
uip->uiListEnd();
}
void Packer::doFileInfo()
{
uip->uiFileInfoStart();
fileInfo();
uip->uiFileInfoEnd();
}
/*************************************************************************
// default actions
**************************************************************************/
void Packer::test()
{
unpack(NULL);
}
void Packer::list()
{
uip->uiList();
}
void Packer::fileInfo()
{
// FIXME: subclasses should list their sections here
// We also should try to get a nice layout...
}
bool Packer::testUnpackVersion(int version) const
{
if (version != ph_version && ph_version != -1)
throwCantUnpack("program has been modified; run a virus checker!");
if (!canUnpackVersion(version))
throwCantUnpack("I am not compatible with older versions of UPX");
return true;
}
bool Packer::testUnpackFormat(int format) const
{
if (format != ph_format && ph_format != -1)
throwCantUnpack("program has been modified; run a virus checker!");
return canUnpackFormat(format);
}
bool ph_skipVerify(const PackHeader &ph)
{
if (M_IS_DEFLATE(ph.method))
return false;
if (M_IS_LZMA(ph.method))
return false;
if (ph.level > 1)
return false;
return true;
}
/*************************************************************************
// compress - wrap call to low-level upx_compress()
**************************************************************************/
bool Packer::compress(upx_bytep i_ptr, unsigned i_len, upx_bytep o_ptr,
const upx_compress_config_t *cconf_parm)
{
ph.u_len = i_len;
ph.c_len = 0;
assert(ph.level >= 1); assert(ph.level <= 10);
// Avoid too many progress bar updates. 64 is s->bar_len in ui.cpp.
unsigned step = (ph.u_len < 64*1024) ? 0 : ph.u_len / 64;
// save current checksums
ph.saved_u_adler = ph.u_adler;
ph.saved_c_adler = ph.c_adler;
// update checksum of uncompressed data
ph.u_adler = upx_adler32(i_ptr, ph.u_len, ph.u_adler);
// set compression parameters
upx_compress_config_t cconf; cconf.reset();
if (cconf_parm)
cconf = *cconf_parm;
// cconf options
if (M_IS_NRV2B(ph.method) || M_IS_NRV2D(ph.method) || M_IS_NRV2E(ph.method))
{
if (opt->crp.crp_ucl.c_flags != -1)
cconf.conf_ucl.c_flags = opt->crp.crp_ucl.c_flags;
if (opt->crp.crp_ucl.p_level != -1)
cconf.conf_ucl.p_level = opt->crp.crp_ucl.p_level;
if (opt->crp.crp_ucl.h_level != -1)
cconf.conf_ucl.h_level = opt->crp.crp_ucl.h_level;
if (opt->crp.crp_ucl.max_offset != UINT_MAX && opt->crp.crp_ucl.max_offset < cconf.conf_ucl.max_offset)
cconf.conf_ucl.max_offset = opt->crp.crp_ucl.max_offset;
if (opt->crp.crp_ucl.max_match != UINT_MAX && opt->crp.crp_ucl.max_match < cconf.conf_ucl.max_match)
cconf.conf_ucl.max_match = opt->crp.crp_ucl.max_match;
#if (WITH_NRV)
if (ph.level >= 7 || (ph.level >= 4 && ph.u_len >= 512*1024))
step = 0;
#endif
}
if (M_IS_LZMA(ph.method))
{
oassign(cconf.conf_lzma.pos_bits, opt->crp.crp_lzma.pos_bits);
oassign(cconf.conf_lzma.lit_pos_bits, opt->crp.crp_lzma.lit_pos_bits);
oassign(cconf.conf_lzma.lit_context_bits, opt->crp.crp_lzma.lit_context_bits);
oassign(cconf.conf_lzma.dict_size, opt->crp.crp_lzma.dict_size);
oassign(cconf.conf_lzma.num_fast_bytes, opt->crp.crp_lzma.num_fast_bytes);
}
if (M_IS_DEFLATE(ph.method))
{
oassign(cconf.conf_zlib.mem_level, opt->crp.crp_zlib.mem_level);
oassign(cconf.conf_zlib.window_bits, opt->crp.crp_zlib.window_bits);
oassign(cconf.conf_zlib.strategy, opt->crp.crp_zlib.strategy);
}
if (uip->ui_pass >= 0)
uip->ui_pass++;
uip->startCallback(ph.u_len, step, uip->ui_pass, uip->ui_total_passes);
uip->firstCallback();
//OutputFile::dump("data.raw", in, ph.u_len);
// compress
int r = upx_compress(i_ptr, ph.u_len, o_ptr, &ph.c_len,
uip->getCallback(),
ph.method, ph.level, &cconf, &ph.compress_result);
//uip->finalCallback(ph.u_len, ph.c_len);
uip->endCallback();
if (r == UPX_E_OUT_OF_MEMORY)
throwOutOfMemoryException();
if (r != UPX_E_OK)
throwInternalError("compression failed");
if (M_IS_NRV2B(ph.method) || M_IS_NRV2D(ph.method) || M_IS_NRV2E(ph.method))
{
const ucl_uint *res = ph.compress_result.result_ucl.result;
//ph.min_offset_found = res[0];
ph.max_offset_found = res[1];
//ph.min_match_found = res[2];
ph.max_match_found = res[3];
//ph.min_run_found = res[4];
ph.max_run_found = res[5];
ph.first_offset_found = res[6];
//ph.same_match_offsets_found = res[7];
if (cconf_parm)
{
assert(cconf.conf_ucl.max_offset == 0 || cconf.conf_ucl.max_offset >= ph.max_offset_found);
assert(cconf.conf_ucl.max_match == 0 || cconf.conf_ucl.max_match >= ph.max_match_found);
}
}
//printf("\nPacker::compress: %d/%d: %7d -> %7d\n", ph.method, ph.level, ph.u_len, ph.c_len);
if (!checkCompressionRatio(ph.u_len, ph.c_len))
return false;
// return in any case if not compressible
if (ph.c_len >= ph.u_len)
return false;
// update checksum of compressed data
ph.c_adler = upx_adler32(o_ptr, ph.c_len, ph.c_adler);
// Decompress and verify. Skip this when using the fastest level.
if (!ph_skipVerify(ph))
{
// decompress
unsigned new_len = ph.u_len;
r = upx_decompress(o_ptr, ph.c_len, i_ptr, &new_len, ph.method, &ph.compress_result);
if (r == UPX_E_OUT_OF_MEMORY)
throwOutOfMemoryException();
//printf("%d %d: %d %d %d\n", ph.method, r, ph.c_len, ph.u_len, new_len);
if (r != UPX_E_OK)
throwInternalError("decompression failed");
if (new_len != ph.u_len)
throwInternalError("decompression failed (size error)");
// verify decompression
if (ph.u_adler != upx_adler32(i_ptr, ph.u_len, ph.saved_u_adler))
throwInternalError("decompression failed (checksum error)");
}
return true;
}
#if 0
bool Packer::compress(upx_bytep in, upx_bytep out,
const upx_compress_config_t *cconf)
{
return ph_compress(ph, in, out, cconf);
}
#endif
bool Packer::checkDefaultCompressionRatio(unsigned u_len, unsigned c_len) const
{
assert((int)u_len > 0);
assert((int)c_len > 0);
if (c_len >= u_len)
return false;
unsigned gain = u_len - c_len;
if (gain < 512) // need at least 512 bytes gain
return false;
#if 1
if (gain >= 4096) // ok if we have 4096 bytes gain
return true;
if (gain >= u_len / 16) // ok if we have 6.25% gain
return true;
return false;
#else
return true;
#endif
}
bool Packer::checkCompressionRatio(unsigned u_len, unsigned c_len) const
{
return checkDefaultCompressionRatio(u_len, c_len);
}
bool Packer::checkFinalCompressionRatio(const OutputFile *fo) const
{
const unsigned u_len = file_size;
const unsigned c_len = fo->getBytesWritten();
return checkDefaultCompressionRatio(u_len, c_len);
}
/*************************************************************************
// decompress
**************************************************************************/
void ph_decompress(PackHeader &ph, const upx_bytep in, upx_bytep out,
bool verify_checksum, Filter *ft)
{
unsigned adler;
// verify checksum of compressed data
if (verify_checksum)
{
adler = upx_adler32(in, ph.c_len, ph.saved_c_adler);
if (adler != ph.c_adler)
throwChecksumError();
}
// decompress
if (ph.u_len < ph.c_len) {
throwCantUnpack("header corrupted");
}
unsigned new_len = ph.u_len;
int r = upx_decompress(in, ph.c_len, out, &new_len, ph.method, &ph.compress_result);
if (r == UPX_E_OUT_OF_MEMORY)
throwOutOfMemoryException();
if (r != UPX_E_OK || new_len != ph.u_len)
throwCompressedDataViolation();
// verify checksum of decompressed data
if (verify_checksum)
{
if (ft)
ft->unfilter(out, ph.u_len);
adler = upx_adler32(out, ph.u_len, ph.saved_u_adler);
if (adler != ph.u_adler)
throwChecksumError();
}
}
void Packer::decompress(const upx_bytep in, upx_bytep out,
bool verify_checksum, Filter *ft)
{
ph_decompress(ph, in, out, verify_checksum, ft);
}
/*************************************************************************
// overlapping decompression
**************************************************************************/
static
bool ph_testOverlappingDecompression(const PackHeader &ph,
const upx_bytep buf,
const upx_bytep tbuf,
unsigned overlap_overhead)
{
if (ph.c_len >= ph.u_len)
return false;
assert((int) overlap_overhead >= 0);
assert((int) (ph.u_len + overlap_overhead) >= 0);
// Because upx_test_overlap() does not use the asm_fast decompressor
// we must account for extra 3 bytes that asm_fast does use,
// or else we may fail at runtime decompression.
unsigned extra = 0;
if (M_IS_NRV2B(ph.method) || M_IS_NRV2D(ph.method) || M_IS_NRV2E(ph.method))
extra = 3;
if (overlap_overhead <= 4 + extra) // don't waste time here
return false;
overlap_overhead -= extra;
unsigned src_off = ph.u_len + overlap_overhead - ph.c_len;
unsigned new_len = ph.u_len;
int r = upx_test_overlap(buf - src_off, tbuf,
src_off, ph.c_len, &new_len,
ph.method, &ph.compress_result);
if (r == UPX_E_OUT_OF_MEMORY)
throwOutOfMemoryException();
return (r == UPX_E_OK && new_len == ph.u_len);
}
bool Packer::testOverlappingDecompression(const upx_bytep buf, const upx_bytep tbuf,
unsigned overlap_overhead) const
{
return ph_testOverlappingDecompression(ph, buf, tbuf, overlap_overhead);
}
void Packer::verifyOverlappingDecompression(Filter *ft)
{
assert(ph.c_len < ph.u_len);
assert((int)ph.overlap_overhead > 0);
// Idea:
// obuf[] was allocated with MemBuffer::allocForCompression(), and
// its contents are no longer needed, i.e. the compressed data
// must have been already written.
// We now can perform a real overlapping decompression and
// verify the checksum.
//
// Note:
// This verify is just because of complete paranoia that there
// could be a hidden bug in the upx_test_overlap implementation,
// and it should not be necessary at all.
//
// See also:
// Filter::verifyUnfilter()
if (ph_skipVerify(ph))
return;
unsigned offset = (ph.u_len + ph.overlap_overhead) - ph.c_len;
if (offset + ph.c_len > obuf.getSize())
return;
memmove(obuf + offset, obuf, ph.c_len);
decompress(obuf + offset, obuf, true, ft);
obuf.checkState();
}
void Packer::verifyOverlappingDecompression(upx_bytep o_ptr, unsigned o_size, Filter *ft)
{
assert(ph.c_len < ph.u_len);
assert((int)ph.overlap_overhead > 0);
if (ph_skipVerify(ph))
return;
unsigned offset = (ph.u_len + ph.overlap_overhead) - ph.c_len;
if (offset + ph.c_len > o_size)
return;
memmove(o_ptr + offset, o_ptr, ph.c_len);
decompress(o_ptr + offset, o_ptr, true, ft);
}
/*************************************************************************
// Find overhead for in-place decompression in a heuristic way
// (using a binary search). Return 0 on error.
//
// To speed up things:
// - you can pass the range of an acceptable interval (so that
// we can succeed early)
// - you can enforce an upper_limit (so that we can fail early)
**************************************************************************/
unsigned Packer::findOverlapOverhead(const upx_bytep buf,
const upx_bytep tbuf,
unsigned range,
unsigned upper_limit) const
{
assert((int) range >= 0);
// prepare to deal with very pessimistic values
unsigned low = 1;
unsigned high = UPX_MIN(ph.u_len + 512, upper_limit);
// but be optimistic for first try (speedup)
unsigned m = UPX_MIN(16u, high);
//
unsigned overhead = 0;
unsigned nr = 0; // statistics
while (high >= low)
{
assert(m >= low); assert(m <= high);
assert(m < overhead || overhead == 0);
nr++;
bool success = testOverlappingDecompression(buf, tbuf, m);
//printf("testOverlapOverhead(%d): %d %d: %d -> %d\n", nr, low, high, m, (int)success);
if (success)
{
overhead = m;
// Succeed early if m lies in [low .. low+range-1], i.e. if
// if the range of the current interval is <= range.
// if (m <= low + range - 1)
// if (m < low + range)
if (m - low < range) // avoid underflow
break;
high = m - 1;
}
else
low = m + 1;
////m = (low + high) / 2;
m = (low & high) + ((low ^ high) >> 1); // avoid overflow
}
//printf("findOverlapOverhead: %d (%d tries)\n", overhead, nr);
if (overhead == 0)
throwInternalError("this is an oo bug");
UNUSED(nr);
return overhead;
}
/*************************************************************************
// file i/o utils
**************************************************************************/
void Packer::handleStub(InputFile *fif, OutputFile *fo, unsigned size)
{
if (fo)
{
if (size > 0)
{
// copy stub from exe
info("Copying original stub: %u bytes", size);
ByteArray(stub, size);
fif->seek(0,SEEK_SET);
fif->readx(stub,size);
fo->write(stub,size);
}
else
{
// no stub
}
}
}
void Packer::checkOverlay(unsigned overlay)
{
if ((int)overlay < 0 || (off_t)overlay > file_size)
throw OverlayException("invalid overlay size; file is possibly corrupt");
if (overlay == 0)
return;
info("Found overlay: %d bytes", overlay);
if (opt->overlay == opt->SKIP_OVERLAY)
throw OverlayException("file has overlay -- skipped; try '--overlay=copy'");
}
void Packer::copyOverlay(OutputFile *fo, unsigned overlay,
MemBuffer *buf,
bool do_seek)
{
assert((int)overlay >= 0);
assert((off_t)overlay < file_size);
buf->checkState();
if (!fo || overlay == 0)
return;
if (opt->overlay != opt->COPY_OVERLAY)
{
assert(opt->overlay == opt->STRIP_OVERLAY);
infoWarning("stripping overlay: %d bytes", overlay);
return;
}
info("Copying overlay: %d bytes", overlay);
if (do_seek)
fi->seek(-(off_t)overlay, SEEK_END);
// get buffer size, align to improve i/o speed
unsigned buf_size = buf->getSize();
if (buf_size > 65536)
buf_size = ALIGN_DOWN(buf_size, 4096u);
assert((int)buf_size > 0);
do {
unsigned len = overlay < buf_size ? overlay : buf_size;
fi->readx(buf, len);
fo->write(buf, len);
overlay -= len;
} while (overlay > 0);
buf->checkState();
}
// Create a pseudo-unique program id.
unsigned Packer::getRandomId() const
{
if (opt->debug.disable_random_id)
return 0x01020304;
unsigned id = 0;
#if 0 && defined(__unix__)
// Don't consume precious bytes from /dev/urandom.
int fd = open("/dev/urandom", O_RDONLY | O_BINARY);
if (fd < 0)
fd = open("/dev/random", O_RDONLY | O_BINARY);
if (fd >= 0)
{
if (read(fd, &id, 4) != 4)
id = 0;
close(fd);
}
#endif
while (id == 0)
{
#if !(HAVE_GETTIMEOFDAY) || ((ACC_OS_DOS32) && defined(__DJGPP__))
id ^= (unsigned) time(NULL);
id ^= ((unsigned) clock()) << 12;
#else
struct timeval tv;
gettimeofday(&tv, 0);
id ^= (unsigned) tv.tv_sec;
id ^= ((unsigned) tv.tv_usec) << 12; // shift into high-bits
#endif
#if (HAVE_GETPID)
id ^= (unsigned) getpid();
#endif
id ^= (unsigned) fi->st.st_ino;
id ^= (unsigned) fi->st.st_atime;
id ^= (unsigned) rand();
}
return id;
}
/*************************************************************************
// packheader util
**************************************************************************/
// this is called directly after the constructor from class PackMaster
void Packer::initPackHeader()
{
mem_clear(&ph, sizeof(ph));
ph.version = getVersion();
ph.format = getFormat();
ph.method = M_NONE;
ph.level = -1;
ph.u_adler = ph.c_adler = ph.saved_u_adler = ph.saved_c_adler = upx_adler32(NULL,0);
ph.buf_offset = 0;
ph.u_file_size = file_size;
}
// this is called directly after canPack() from class PackMaster
void Packer::updatePackHeader()
{
assert(opt->cmd == CMD_COMPRESS);
//
const int *m = getCompressionMethods(opt->method, opt->level);
ph.method = m[0];
ph.level = opt->level;
if (ph.level < 0)
ph.level = file_size < 512*1024 ? 8 : 7;
//
assert(isValidCompressionMethod(ph.method));
assert(1 <= ph.level && ph.level <= 10);
}
// FIXME: remove patchPackHeader() and fold into relocateLoader();
// then make linker->relocate() private (friend Packer)
int Packer::patchPackHeader(void *b, int blen)
{
assert(isValidFilter(ph.filter));
const int size = ph.getPackHeaderSize();
if (linker->findSection("UPX1HEAD", false))
assert(size == linker->getSectionSize("UPX1HEAD"));
int boff = find_le32(b, blen, UPX_MAGIC_LE32);
checkPatch(b, blen, boff, size);
unsigned char *p = (unsigned char *)b + boff;
ph.putPackHeader(p);
return boff;
}
bool Packer::getPackHeader(void *b, int blen, bool allow_incompressible)
{
if (!ph.fillPackHeader((unsigned char *)b, blen))
return false;
if (ph.version > getVersion())
throwCantUnpack("need a newer version of UPX");
// Some formats might be able to unpack old versions because
// their implementation hasn't changed. Ask them.
if (opt->cmd != CMD_FILEINFO)
if (!testUnpackVersion(ph.version))
return false;
if (ph.c_len > ph.u_len
|| (ph.c_len == ph.u_len && !allow_incompressible)
|| (off_t)ph.c_len >= file_size
|| ph.version <= 0 || ph.version >= 0xff)
throwCantUnpack("header corrupted");
else if ((off_t)ph.u_len > ph.u_file_size)
{
#if 0
// FIXME: does this check make sense w.r.t. overlays ???
if (ph.format == UPX_F_WIN32_PE || ph.format == UPX_F_DOS_EXE)
// may get longer
((void)0);
else
throwCantUnpack("header size corrupted");
#endif
}
if (!isValidCompressionMethod(ph.method))
throwCantUnpack("unknown compression method (try a newer version of UPX)");
// Some formats might be able to unpack "subformats". Ask them.
if (!testUnpackFormat(ph.format))
return false;
return true;
}
bool Packer::readPackHeader(int len, bool allow_incompressible)
{
assert((int)len > 0);
MemBuffer buf(len);
len = fi->read(buf, len);
if (len <= 0)
return false;
return getPackHeader(buf, len, allow_incompressible);
}
void Packer::checkAlreadyPacked(const void *b, int blen)
{
int boff = find_le32(b, blen, UPX_MAGIC_LE32);
if (boff < 0)
return;
// FIXME: could add some more checks to verify that this
// is a real PackHeader, e.g.
//
//PackHeader tmp;
//if (!tmp.fillPackHeader((unsigned char *)b + boff, blen - boff))
// return;
//
// This also would require that the buffer in 'b' holds
// the full PackHeader, and not only the 4 magic bytes.
throwAlreadyPacked();
}
/*************************************************************************
// patch util for loader
**************************************************************************/
void Packer::checkPatch(void *b, int blen, int boff, int size)
{
if (b == NULL && blen == 0 && boff == 0 && size == 0)
{
// reset
last_patch = NULL;
last_patch_len = 0;
last_patch_off = 0;
return;
}
if (b == NULL || blen <= 0 || boff < 0 || size <= 0)
throwBadLoader();
if (boff + size <= 0 || boff + size > blen)
throwBadLoader();
//printf("checkPatch: %p %5d %5d %2d\n", b, blen, boff, size);
if (b == last_patch)
{
if (boff + size > last_patch_off)
throwInternalError("invalid patch order");
// The next check is not strictly necessary, but the buffer
// length should better not increase...
if (blen > last_patch_len)
throwInternalError("invalid patch order (length)");
}
else
last_patch = b;
last_patch_len = blen;
last_patch_off = boff;
}
int Packer::patch_be16(void *b, int blen, unsigned old, unsigned new_)
{
int boff = find_be16(b, blen, old);
checkPatch(b, blen, boff, 2);
unsigned char *p = (unsigned char *)b + boff;
set_be16(p, new_);
return boff;
}
int Packer::patch_be16(void *b, int blen, const void *old, unsigned new_)
{
int boff = find(b, blen, old, 2);
checkPatch(b, blen, boff, 2);
unsigned char *p = (unsigned char *)b + boff;
set_be16(p, new_);
return boff;
}
int Packer::patch_be32(void *b, int blen, unsigned old, unsigned new_)
{
int boff = find_be32(b, blen, old);
checkPatch(b, blen, boff, 4);
unsigned char *p = (unsigned char *)b + boff;
set_be32(p, new_);
return boff;
}
int Packer::patch_be32(void *b, int blen, const void *old, unsigned new_)
{
int boff = find(b, blen, old, 4);
checkPatch(b, blen, boff, 4);
unsigned char *p = (unsigned char *)b + boff;
set_be32(p, new_);
return boff;
}
int Packer::patch_le16(void *b, int blen, unsigned old, unsigned new_)
{
int boff = find_le16(b, blen, old);
checkPatch(b, blen, boff, 2);
unsigned char *p = (unsigned char *)b + boff;
set_le16(p, new_);
return boff;
}
int Packer::patch_le16(void *b, int blen, const void *old, unsigned new_)
{
int boff = find(b, blen, old, 2);
checkPatch(b, blen, boff, 2);
unsigned char *p = (unsigned char *)b + boff;
set_le16(p, new_);
return boff;
}
int Packer::patch_le32(void *b, int blen, unsigned old, unsigned new_)
{
int boff = find_le32(b, blen, old);
checkPatch(b, blen, boff, 4);
unsigned char *p = (unsigned char *)b + boff;
set_le32(p, new_);
return boff;
}
int Packer::patch_le32(void *b, int blen, const void *old, unsigned new_)
{
int boff = find(b, blen, old, 4);
checkPatch(b, blen, boff, 4);
unsigned char *p = (unsigned char *)b + boff;
set_le32(p, new_);
return boff;
}
/*************************************************************************
// relocation util
**************************************************************************/
upx_byte *Packer::optimizeReloc(upx_byte *in, unsigned relocnum,
upx_byte *out, upx_byte *image,
int bswap, int *big, int bits)
{
if (opt->exact)
throwCantPackExact();
*big = 0;
if (relocnum == 0)
return out;
qsort(in,relocnum,4,le32_compare);
unsigned jc,pc,oc;
upx_byte *fix = out;
pc = (unsigned) -4;
for (jc = 0; jc<relocnum; jc++)
{
oc = get_le32(in+jc*4) - pc;
if (oc == 0)
continue;
else if ((int)oc < 4)
throwCantPack("overlapping fixups");
else if (oc < 0xF0)
*fix++ = (unsigned char) oc;
else if (oc < 0x100000)
{
*fix++ = (unsigned char) (0xF0+(oc>>16));
*fix++ = (unsigned char) oc;
*fix++ = (unsigned char) (oc>>8);
}
else
{
*big = 1;
*fix++ = 0xf0;
*fix++ = 0;
*fix++ = 0;
set_le32(fix,oc);
fix += 4;
}
pc += oc;
if (bswap)
{
if (bits == 32)
acc_ua_swab32s(image + pc);
else if (bits == 64)
set_be64(image + pc, get_le64(image + pc));
else
throwInternalError("optimizeReloc problem");
}
}
*fix++ = 0;
return fix;
}
upx_byte *Packer::optimizeReloc32(upx_byte *in, unsigned relocnum,
upx_byte *out, upx_byte *image,
int bswap, int *big)
{
return optimizeReloc(in, relocnum, out, image, bswap, big, 32);
}
upx_byte *Packer::optimizeReloc64(upx_byte *in, unsigned relocnum,
upx_byte *out, upx_byte *image,
int bswap, int *big)
{
return optimizeReloc(in, relocnum, out, image, bswap, big, 64);
}
unsigned Packer::unoptimizeReloc(upx_byte **in, upx_byte *image,
MemBuffer *out, int bswap, int bits)
{
upx_byte *p;
unsigned relocn = 0;
for (p = *in; *p; p++, relocn++)
if (*p >= 0xF0)
{
if (*p == 0xF0 && get_le16(p+1) == 0)
p += 4;
p += 2;