denyhosts/clamscan/libclamav/fsg.c

124 lines
3.8 KiB
C
Raw Normal View History

2022-10-22 18:41:00 +08:00
/*
* Copyright (C) 2013-2022 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
* Copyright (C) 2007-2013 Sourcefire, Inc.
*
* Authors: Alberto Wu
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
/*
** defsg.c
**
** 02/08/2k4 - Dumped and reversed
** 02/08/2k4 - Done coding
** 03/08/2k4 - Cleaning and securing
** 04/08/2k4 - Done porting
** 07/08/2k4 - Started adding support for 1.33
*/
/*
** Unpacks an FSG compressed section.
**
** Czesc bart, good asm, nice piece of code ;)
*/
#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif
#include <stdlib.h>
#include "clamav.h"
#include "rebuildpe.h"
#include "others.h"
#include "packlibs.h"
#include "fsg.h"
int unfsg_200(const char *source, char *dest, int ssize, int dsize, uint32_t rva, uint32_t base, uint32_t ep, int file)
{
struct cli_exe_section section; /* Yup, just one ;) */
if (cli_unfsg(source, dest, ssize, dsize, NULL, NULL)) return -1;
section.raw = 0;
section.rsz = dsize;
section.vsz = dsize;
section.rva = rva;
if (!cli_rebuildpe(dest, &section, 1, base, ep, 0, 0, file)) {
cli_dbgmsg("FSG: Rebuilding failed\n");
return 0;
}
return 1;
}
int unfsg_133(const char *source, char *dest, int ssize, int dsize, struct cli_exe_section *sections, int sectcount, uint32_t base, uint32_t ep, int file)
{
const char *tsrc = source;
char *tdst = dest;
int i, upd = 1, offs = 0, lastsz = dsize;
for (i = 0; i <= sectcount; i++) {
char *startd = tdst;
if (cli_unfsg(tsrc, tdst, ssize - (tsrc - source), dsize - (tdst - dest), &tsrc, &tdst) == -1)
return -1;
/* RVA has been filled already in pe.c */
sections[i].raw = offs;
sections[i].rsz = tdst - startd;
/* cli_dbgmsg("Unpacked section %d @%x size %x Vsize =%x \n", i, offs, tdst-startd, dsize - (startd - dest)); */
offs += tdst - startd;
}
/* Sort out the sections */
while (upd) {
upd = 0;
for (i = 0; i < sectcount; i++) {
uint32_t trva, trsz, traw;
if (sections[i].rva <= sections[i + 1].rva)
continue;
trva = sections[i].rva;
traw = sections[i].raw;
trsz = sections[i].rsz;
sections[i].rva = sections[i + 1].rva;
sections[i].rsz = sections[i + 1].rsz;
sections[i].raw = sections[i + 1].raw;
sections[i + 1].rva = trva;
sections[i + 1].raw = traw;
sections[i + 1].rsz = trsz;
upd = 1;
}
}
/* Cure Vsizes and debugspam */
for (i = 0; i <= sectcount; i++) {
if (i != sectcount) {
sections[i].vsz = sections[i + 1].rva - sections[i].rva;
lastsz -= sections[i + 1].rva - sections[i].rva;
} else
sections[i].vsz = lastsz;
cli_dbgmsg("FSG: .SECT%d RVA:%x VSize:%x ROffset: %x, RSize:%x\n", i, sections[i].rva, sections[i].vsz, sections[i].raw, sections[i].rsz);
}
if (!cli_rebuildpe(dest, sections, sectcount + 1, base, ep, 0, 0, file)) {
cli_dbgmsg("FSG: Rebuilding failed\n");
return 0;
}
return 1;
}