/*

  *  Copyright (C) 2013-2019 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;

 }