/*
  *  Copyright (C) 2009 Sourcefire, Inc.
  *
  *  Authors: aCaB
  *
  *  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.
  */
 
 /* 7zip scanner */
 
 #if HAVE_CONFIG_H
 #include "clamav-config.h"
 #endif
 
 #include <stdio.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 
 #include "others.h"
 #include "lzma_iface.h"

 #include "scanners.h"

 #include "matcher.h"

 #include "7z/7zFile.h"
 #include "7z/7zCrc.h"
 #include "7z/Archive/7z/7zIn.h"
 #include "7z/Archive/7z/7zExtract.h"
 
 static ISzAlloc allocImp = { __lzma_wrap_alloc, __lzma_wrap_free}, allocTempImp = { __lzma_wrap_alloc, __lzma_wrap_free};
 
 int cli_7unz (int fd, cli_ctx *ctx) {
     CFileInStream archiveStream;
     CLookToRead lookStream;
     CSzArEx db;
     UInt32 blockIndex = 0xFFFFFFFF;

     unsigned char *buf = NULL;

     size_t bufsz = 0;
     UInt32 i;
     int dupfd, ret = CL_CLEAN;

     unsigned int fu=0;

 
     if((dupfd = dup(fd)) == -1) {
 	cli_errmsg("cli_7unz: dup() failed\n");
 	return CL_EDUP;
     }
     FileInStream_CreateVTable(&archiveStream);
     archiveStream.file.file = fdopen(dupfd, "rb");
     if(!archiveStream.file.file) {
 	cli_errmsg("cli_7unz: fdopen() failed\n");
 	return CL_EOPEN;
     }
     LookToRead_CreateVTable(&lookStream, False);
     lookStream.realStream = &archiveStream.s;
     LookToRead_Init(&lookStream);
 
     SzArEx_Init(&db);
     if(SzArEx_Open(&db, &lookStream.s, &allocImp, &allocTempImp) != SZ_OK) {
 	SzArEx_Free(&db, &allocImp);
 	cli_dbgmsg("cli_7unz: possibly damaged archive\n");
 	return CL_CLEAN;
     }
     for (i = 0; i < db.db.NumFiles; i++) {
 	CSzFileItem *f = db.db.Files + i;
         size_t offset;
         size_t usize;
 
 	if(f->IsDir || !f->Size) continue;
 	if(ctx->engine->maxfilesize && f->Size > ctx->engine->maxfilesize) {

 	    cli_dbgmsg("cli_7unz: skipping stream due to size limits (%llu vs %llu)\n", (long long)f->Size, (long long)ctx->engine->maxfilesize);

 	    continue;
 	}

 	if(cli_matchmeta(ctx, f->Name, 0, f->Size, 0, i + 1, 0, NULL) == CL_VIRUS) {
 	    ret = CL_VIRUS;
 	    break;
 	}

 	if (ctx->engine->maxfiles && fu>=ctx->engine->maxfiles) {
 	    cli_dbgmsg("cli_7unz: Files limit reached (max: %u)\n", ctx->engine->maxfiles);
 	    ret=CL_EMAXFILES;
 	    break;
 	}

 	cli_dbgmsg("cli_7unz: Extracting file %s\n", f->Name);
 	if(SzAr_Extract(&db, &lookStream.s, i, &blockIndex, &buf, &bufsz, &offset, &usize, &allocImp, &allocTempImp) == SZ_OK) {
 	    char *fname;
 	    int ofd;
 
 	    if(!usize) {
 		cli_dbgmsg("cli_7unz: stream uncompressed to an empty file\n");
 		continue;
 	    }

 	    fu++;

 	    if(!(fname = cli_gentemp(ctx->engine->tmpdir))) {
 		ret = CL_EMEM;
 		break;
 	    }
 	    if((ofd = open(fname, O_RDWR|O_CREAT|O_TRUNC|O_BINARY, S_IRUSR|S_IWUSR)) < 0) {
 		cli_errmsg("cli_7unz: failed to create file %s\n", fname);
 		free(fname);
 		ret = CL_ECREAT;
 		break;
 	    }
 	    if(cli_writen(ofd, buf, usize) <= 0) {
 		close(ofd);
 		if(cli_unlink(fname)) ret = CL_EUNLINK;
 		else ret = CL_EWRITE;
 		free(fname);
 		break;
 	    }
 	    cli_dbgmsg("cli_7unz: extracted to %s\n", fname);
 	    lseek(ofd, 0, SEEK_SET);
 	    ret = cli_magic_scandesc(ofd, ctx);
 	    close(ofd);
 	    if(!ctx->engine->keeptmp)
 		if(cli_unlink(fname)) ret = CL_EUNLINK;
 	    free(fname);
 	    if(ret == CL_EUNLINK || ret == CL_VIRUS)
 		break;
 	} else {
 	    cli_dbgmsg("cli_7unz: decompression failed\n");
 	}
     }
     if(buf) free(buf);
     SzArEx_Free(&db, &allocImp);
     fclose(archiveStream.file.file);
     return ret;
 }