ClamAV is an open source (GPLv2) anti-virus toolkit.
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clamav/clamav-devel/libclamav/scanners.c

1098 lines
29 KiB

/*
* Copyright (C) 2002 - 2004 Tomasz Kojm <tkojm@clamav.net>
* With enhancements from Thomas Lamy <Thomas.Lamy@in-online.net>
*
* This program is free software; you can redistribute it and/or modify
* it 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; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#ifdef CL_THREAD_SAFE
# include <pthread.h>
pthread_mutex_t cli_scanrar_mutex = PTHREAD_MUTEX_INITIALIZER;
#endif
int cli_scanrar_inuse = 0;
#include "clamav.h"
#include "others.h"
#include "matcher.h"
#include "unrarlib.h"
#include "ole2_extract.h"
#include "vba_extract.h"
#include "msexpand.h"
#include "scanners.h"
#ifdef HAVE_ZLIB_H
#include <zlib.h>
#include <zzip.h>
#endif
#ifdef HAVE_BZLIB_H
#include <bzlib.h>
#endif
#define SCAN_ARCHIVE (options & CL_ARCHIVE)
#define SCAN_MAIL (options & CL_MAIL)
#define SCAN_OLE2 (options & CL_OLE2)
#define DISABLE_RAR (options & CL_DISABLERAR)
#define DETECT_ENCRYPTED (options & CL_ENCRYPTED)
struct cli_magic_s {
int offset;
const char *magic;
size_t length;
const char *descr;
cli_file_t type;
};
#define MAGIC_BUFFER_SIZE 26
static const struct cli_magic_s cli_magic[] = {
/* Executables */
{0, "MZ", 2, "DOS/W32 executable", CL_DOSEXE},
/* Archives */
{0, "Rar!", 4, "RAR", CL_RARFILE},
{0, "PK\003\004", 4, "ZIP", CL_ZIPFILE},
{0, "\037\213", 2, "GZip", CL_GZFILE},
{0, "BZh", 3, "BZip", CL_BZFILE},
{0, "SZDD", 4, "compress.exe'd", CL_MSCFILE},
/* Mail */
{0, "From ", 5, "MBox", CL_MAILFILE},
{0, "Received", 8, "Raw mail", CL_MAILFILE},
{0, "Return-Path: ", 13, "Maildir", CL_MAILFILE},
{0, "Return-path: ", 13, "Maildir", CL_MAILFILE},
{0, "Delivered-To: ", 14, "Mail", CL_MAILFILE},
{0, "X-UIDL: ", 8, "Mail", CL_MAILFILE},
{0, "X-Apparently-To: ", 17, "Mail", CL_MAILFILE},
{0, "X-Envelope-From: ", 17, "Mail", CL_MAILFILE},
{0, "X-Symantec-", 11, "Symantec", CL_MAILFILE},
{0, "X-EVS", 5, "EVS mail", CL_MAILFILE},
{0, ">From ", 6, "Mail", CL_MAILFILE},
{0, "Date: ", 6, "Mail", CL_MAILFILE},
{0, "Message-Id: ", 12, "Mail", CL_MAILFILE},
{0, "Message-ID: ", 12, "Mail", CL_MAILFILE},
{0, "Envelope-to: ", 13, "Mail", CL_MAILFILE},
{0, "Delivery-date: ", 15, "Mail", CL_MAILFILE},
{0, "To: ", 4, "Mail", CL_MAILFILE},
{0, "Subject: ", 9, "Mail", CL_MAILFILE},
{0, "For: ", 5, "Eserv mail", CL_MAILFILE},
{0, "From: ", 6, "Exim mail", CL_MAILFILE},
{0, "v:\015\012Received: ", 14, "VPOP3 Mail (DOS)", CL_MAILFILE},
{0, "v:\012Received: ", 13, "VPOP3 Mail (UNIX)", CL_MAILFILE},
{0, "Hi. This is the qmail-send", 26, "Qmail bounce", CL_MAILFILE},
/* Others */
{0, "\320\317\021\340\241\261\032\341",
8, "OLE2 container", CL_OLE2FILE},
/* Ignored types */
{0, "\000\000\001\263", 4, "MPEG video stream", CL_DATAFILE},
{0, "\000\000\001\272", 4, "MPEG sys stream", CL_DATAFILE},
{0, "RIFF", 4, "RIFF", CL_DATAFILE},
{0, "GIF", 3, "GIF", CL_DATAFILE},
{0, "\x89PNG", 4, "PNG", CL_DATAFILE},
{0, "\377\330\377", 4, "JPEG", CL_DATAFILE},
{0, "BM", 2, "BMP", CL_DATAFILE},
{0, "OggS", 4, "Ogg Stream", CL_DATAFILE},
{0, "ID3", 3, "MP3", CL_DATAFILE},
{0, "\377\373\220", 3, "MP3", CL_DATAFILE},
{0, "\%PDF-", 5, "PDF document", CL_DATAFILE},
{0, "\%!PS-Adobe-", 11, "PostScript", CL_DATAFILE},
{0, "\060\046\262\165\216\146\317", 7, "WMA/WMV/ASF", CL_DATAFILE},
{0, ".RMF" , 4, "Real Media File", CL_DATAFILE},
{-1, NULL, 0, NULL, CL_UNKNOWN_TYPE}
};
cli_file_t cli_filetype(const char *buf, size_t buflen)
{
int i;
for (i = 0; cli_magic[i].magic; i++) {
if (buflen >= cli_magic[i].offset+cli_magic[i].length) {
if (memcmp(buf+cli_magic[i].offset, cli_magic[i].magic, cli_magic[i].length) == 0) {
cli_dbgmsg("Recognized %s file\n", cli_magic[i].descr);
return cli_magic[i].type;
}
}
}
return CL_UNKNOWN_TYPE;
}
static int cli_magic_scandesc(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev);
static int cli_scanfile(const char *filename, const char **virname, unsigned long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev);
static int cli_scandesc(int desc, const char **virname, long int *scanned, const struct cl_node *root)
{
char *buffer, *buff, *endbl, *pt;
int bytes, buffsize, length, ret, *partcnt;
/* prepare the buffer */
buffsize = root->maxpatlen + SCANBUFF;
if(!(buffer = (char *) cli_calloc(buffsize, sizeof(char)))) {
cli_dbgmsg("cli_scandesc(): unable to cli_malloc(%d)\n", buffsize);
return CL_EMEM;
}
if((partcnt = (int *) cli_calloc(root->partsigs + 1, sizeof(int))) == NULL) {
cli_dbgmsg("cli_scandesc(): unable to cli_calloc(%d, %d)\n", root->partsigs + 1, sizeof(int));
free(buffer);
return CL_EMEM;
}
buff = buffer;
buff += root->maxpatlen; /* pointer to read data block */
endbl = buff + SCANBUFF - root->maxpatlen; /* pointer to the last block
* length of root->maxpatlen
*/
pt= buff;
length = SCANBUFF;
while((bytes = read(desc, buff, SCANBUFF)) > 0) {
if(scanned != NULL)
*scanned += bytes / CL_COUNT_PRECISION;
if(bytes < SCANBUFF)
length -= SCANBUFF - bytes;
if((ret = cli_scanbuff(pt, length, virname, root, partcnt)) != CL_CLEAN) {
free(buffer);
free(partcnt);
return ret;
}
if(bytes == SCANBUFF)
memmove(buffer, endbl, root->maxpatlen);
pt = buffer;
length=buffsize;
}
free(buffer);
free(partcnt);
return CL_CLEAN;
}
#ifdef CL_THREAD_SAFE
static void cli_unlock_mutex(void *mtx)
{
cli_dbgmsg("Pthread cancelled. Unlocking mutex.\n");
pthread_mutex_unlock(mtx);
}
#endif
static int cli_scanrar(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
FILE *tmp = NULL;
int files = 0, fd, ret = CL_CLEAN, afiles;
ArchiveList_struct *rarlist = NULL;
ArchiveList_struct *rarlist_head = NULL;
char *rar_data_ptr;
unsigned long rar_data_size;
cli_dbgmsg("Starting scanrar()\n");
#ifdef CL_THREAD_SAFE
pthread_cleanup_push(cli_unlock_mutex, &cli_scanrar_mutex);
pthread_mutex_lock(&cli_scanrar_mutex);
cli_scanrar_inuse = 1;
#endif
if(! (afiles = urarlib_list(desc, (ArchiveList_struct *) &rarlist))) {
#ifdef CL_THREAD_SAFE
pthread_mutex_unlock(&cli_scanrar_mutex);
cli_scanrar_inuse = 0;
#endif
return CL_ERAR;
}
cli_dbgmsg("Rar -> Number of archived files: %d\n", afiles);
rarlist_head = rarlist;
while(rarlist) {
if(DETECT_ENCRYPTED && (rarlist->item.Flags & 4)) {
files++;
cli_dbgmsg("Rar -> Encrypted files found in archive.\n");
lseek(desc, 0, SEEK_SET);
if(cli_scandesc(desc, virname, scanned, root) != CL_VIRUS)
*virname = "Encrypted.RAR";
ret = CL_VIRUS;
break;
}
if(limits) {
if(limits->maxfilesize && (rarlist->item.UnpSize > (unsigned int) limits->maxfilesize)) {
cli_dbgmsg("RAR->%s: Size exceeded (%u, max: %lu)\n", rarlist->item.Name, (unsigned int) rarlist->item.UnpSize, limits->maxfilesize);
rarlist = rarlist->next;
files++;
/* ret = CL_EMAXSIZE; */
continue;
}
if(limits->maxfiles && (files > limits->maxfiles)) {
cli_dbgmsg("RAR: Files limit reached (max: %d)\n", limits->maxfiles);
/* ret = CL_EMAXFILES; */
break;
}
}
if(!!( rarlist->item.FileAttr & RAR_FENTRY_ATTR_DIRECTORY)) {
rarlist = rarlist->next;
files++;
continue;
}
if((tmp = tmpfile()) == NULL) {
cli_dbgmsg("RAR -> Can't generate tmpfile().\n");
#ifdef CL_THREAD_SAFE
pthread_mutex_unlock(&cli_scanrar_mutex);
cli_scanrar_inuse = 0;
#endif
return CL_ETMPFILE;
}
fd = fileno(tmp);
if( urarlib_get(&rar_data_ptr, &rar_data_size, rarlist->item.Name, desc, "clam")) {
cli_dbgmsg("RAR -> Extracted: %s, size: %lu\n", rarlist->item.Name, rar_data_size);
if(fwrite(rar_data_ptr, 1, rar_data_size, tmp) != rar_data_size) {
cli_dbgmsg("RAR -> Can't write() file.\n");
fclose(tmp);
tmp = NULL;
ret = CL_ERAR;
if(rar_data_ptr) {
free(rar_data_ptr);
rar_data_ptr = NULL;
}
break;
}
if(rar_data_ptr) {
free(rar_data_ptr);
rar_data_ptr = NULL;
}
if(fflush(tmp) != 0) {
cli_dbgmsg("fflush() failed: %s\n", strerror(errno));
fclose(tmp);
urarlib_freelist(rarlist_head);
#ifdef CL_THREAD_SAFE
pthread_mutex_unlock(&cli_scanrar_mutex);
cli_scanrar_inuse = 0;
#endif
return CL_EFSYNC;
}
lseek(fd, 0, SEEK_SET);
if((ret = cli_magic_scandesc(fd, virname, scanned, root, limits, options, reclev)) == CL_VIRUS ) {
cli_dbgmsg("RAR -> Found %s virus.\n", *virname);
fclose(tmp);
urarlib_freelist(rarlist);
#ifdef CL_THREAD_SAFE
pthread_mutex_unlock(&cli_scanrar_mutex);
cli_scanrar_inuse = 0;
#endif
return ret;
}
} else {
cli_dbgmsg("RAR -> Can't decompress file %s\n", rarlist->item.Name);
fclose(tmp);
tmp = NULL;
ret = CL_ERAR; /* WinRAR 3.0 ? */
break;
}
fclose(tmp);
tmp = NULL;
rarlist = rarlist->next;
files++;
}
urarlib_freelist(rarlist_head);
#ifdef CL_THREAD_SAFE
pthread_mutex_unlock(&cli_scanrar_mutex);
cli_scanrar_inuse = 0;
pthread_cleanup_pop(0);
#endif
cli_dbgmsg("RAR -> Exit code: %d\n", ret);
return ret;
}
#ifdef HAVE_ZLIB_H
static int cli_scanzip(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
ZZIP_DIR *zdir;
ZZIP_DIRENT zdirent;
ZZIP_FILE *zfp;
FILE *tmp = NULL;
char *buff;
int fd, bytes, files = 0, ret = CL_CLEAN;
struct stat source;
zzip_error_t err;
cli_dbgmsg("Starting scanzip()\n");
if((zdir = zzip_dir_fdopen(dup(desc), &err)) == NULL) {
cli_dbgmsg("Zip -> Not supported file format ?.\n");
cli_dbgmsg("zzip_dir_fdopen() return code: %d\n", err);
/* no return with CL_EZIP due to password protected zips */
return CL_CLEAN;
}
fstat(desc, &source);
if(!(buff = (char *) cli_malloc(FILEBUFF))) {
cli_dbgmsg("cli_scanzip(): unable to malloc(%d)\n", FILEBUFF);
zzip_dir_close(zdir);
return CL_EMEM;
}
while(zzip_dir_read(zdir, &zdirent)) {
if(!zdirent.d_name || !strlen(zdirent.d_name)) { /* Mimail fix */
cli_dbgmsg("strlen(zdirent.d_name) == %d\n", strlen(zdirent.d_name));
*virname = "Suspected.Zip";
ret = CL_VIRUS;
break;
}
cli_dbgmsg("Zip -> %s, compressed: %u, normal: %u, ratio: %d (max: %d)\n", zdirent.d_name, zdirent.d_csize, zdirent.st_size, zdirent.st_size / (zdirent.d_csize+1), limits ? limits->maxratio : -1 );
if(!zdirent.st_size) { /* omit directories and null files */
files++;
continue;
}
if(limits && limits->maxratio > 0 && ((unsigned) zdirent.st_size / (unsigned) zdirent.d_csize) >= limits->maxratio) {
*virname = "Oversized.Zip";
ret = CL_VIRUS;
break;
}
/* work-around for problematic zips (zziplib crashes with them) */
if(zdirent.d_csize < 0 || zdirent.st_size < 0) {
files++;
cli_dbgmsg("Zip -> Malformed archive detected.\n");
/* ret = CL_EMALFZIP; */
/* report it as a virus */
*virname = "Suspected.Zip";
ret = CL_VIRUS;
break;
}
if(DETECT_ENCRYPTED && (zdirent.d_flags & 1 )) {
files++;
cli_dbgmsg("Zip -> Encrypted files found in archive.\n");
lseek(desc, 0, SEEK_SET);
if(cli_scandesc(desc, virname, scanned, root) != CL_VIRUS)
*virname = "Encrypted.Zip";
ret = CL_VIRUS;
break;
}
if(limits) {
if(limits->maxfilesize && (zdirent.st_size > limits->maxfilesize)) {
cli_dbgmsg("Zip -> %s: Size exceeded (%d, max: %ld)\n", zdirent.d_name, zdirent.st_size, limits->maxfilesize);
files++;
/* ret = CL_EMAXSIZE; */
continue; /* this is not a bug */
}
if(limits->maxfiles && (files > limits->maxfiles)) {
cli_dbgmsg("Zip: Files limit reached (max: %d)\n", limits->maxfiles);
/* ret = CL_EMAXFILES; */
break;
}
}
/* generate temporary file and get its descriptor */
if((tmp = tmpfile()) == NULL) {
cli_dbgmsg("Zip -> Can't generate tmpfile().\n");
ret = CL_ETMPFILE;
break;
}
if((zfp = zzip_file_open(zdir, zdirent.d_name, 0)) == NULL) {
cli_dbgmsg("Zip -> %s: Can't open file.\n", zdirent.d_name);
ret = CL_EZIP;
break;
}
while((bytes = zzip_file_read(zfp, buff, FILEBUFF)) > 0) {
if(fwrite(buff, 1, bytes, tmp) != (size_t) bytes) {
cli_dbgmsg("Zip -> Can't fwrite() file: %s\n", strerror(errno));
zzip_file_close(zfp);
zzip_dir_close(zdir);
fclose(tmp);
free(buff);
return CL_EZIP;
}
}
zzip_file_close(zfp);
if(fflush(tmp) != 0) {
cli_errmsg("fflush() failed: %s\n", strerror(errno));
ret = CL_EFSYNC;
break;
}
fd = fileno(tmp);
lseek(fd, 0, SEEK_SET);
if((ret = cli_magic_scandesc(fd, virname, scanned, root, limits, options, reclev)) == CL_VIRUS ) {
cli_dbgmsg("Zip -> Found %s virus.\n", *virname);
ret = CL_VIRUS;
break;
} else if(ret == CL_EMALFZIP) {
/*
* The trick with detection of ZoD only works with higher (>= 5)
* recursion limit level.
*/
cli_dbgmsg("Zip -> Malformed Zip, scanning stopped.\n");
*virname = "Suspected.Zip";
ret = CL_VIRUS;
break;
}
if (tmp) {
fclose(tmp);
tmp = NULL;
}
files++;
}
zzip_dir_close(zdir);
if (tmp) {
fclose(tmp);
tmp = NULL;
}
free(buff);
return ret;
}
static int cli_scangzip(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
int fd, bytes, ret = CL_CLEAN;
long int size = 0;
char *buff;
FILE *tmp = NULL;
gzFile gd;
cli_dbgmsg("in cli_scangzip()\n");
if((gd = gzdopen(dup(desc), "rb")) == NULL) {
cli_dbgmsg("Can't gzdopen() descriptor %d.\n", desc);
return CL_EGZIP;
}
if((tmp = tmpfile()) == NULL) {
cli_dbgmsg("Can't generate tmpfile().\n");
gzclose(gd);
return CL_ETMPFILE;
}
fd = fileno(tmp);
if(!(buff = (char *) cli_malloc(FILEBUFF))) {
cli_dbgmsg("cli_scangzip(): unable to malloc(%d)\n", FILEBUFF);
gzclose(gd);
return CL_EMEM;
}
while((bytes = gzread(gd, buff, FILEBUFF)) > 0) {
size += bytes;
if(limits)
if(limits->maxfilesize && (size + FILEBUFF > limits->maxfilesize)) {
cli_dbgmsg("Gzip->desc(%d): Size exceeded (stopped at %ld, max: %ld)\n", desc, size, limits->maxfilesize);
/* ret = CL_EMAXSIZE; */
break;
}
if(cli_writen(fd, buff, bytes) != bytes) {
cli_dbgmsg("Gzip -> Can't write() file.\n");
fclose(tmp);
gzclose(gd);
free(buff);
return CL_EGZIP;
}
}
free(buff);
gzclose(gd);
if(fsync(fd) == -1) {
cli_dbgmsg("fsync() failed for descriptor %d\n", fd);
fclose(tmp);
return CL_EFSYNC;
}
lseek(fd, 0, SEEK_SET);
if((ret = cli_magic_scandesc(fd, virname, scanned, root, limits, options, reclev)) == CL_VIRUS ) {
cli_dbgmsg("Gzip -> Found %s virus.\n", *virname);
fclose(tmp);
return CL_VIRUS;
}
fclose(tmp);
return ret;
}
#endif
#ifdef HAVE_BZLIB_H
#ifdef NOBZ2PREFIX
#define BZ2_bzReadOpen bzReadOpen
#define BZ2_bzReadClose bzReadClose
#define BZ2_bzRead bzRead
#endif
static int cli_scanbzip(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
int fd, bytes, ret = CL_CLEAN, bzerror = 0;
short memlim = 0;
long int size = 0;
char *buff;
FILE *fs, *tmp = NULL;
BZFILE *bfd;
if((fs = fdopen(dup(desc), "rb")) == NULL) {
cli_errmsg("Can't fdopen() descriptor %d.\n", desc);
return CL_EBZIP;
}
if(limits)
if(limits->archivememlim)
memlim = 1;
if((bfd = BZ2_bzReadOpen(&bzerror, fs, 0, memlim, NULL, 0)) == NULL) {
cli_dbgmsg("Can't initialize bzip2 library (descriptor %d).\n", desc);
fclose(fs);
return CL_EBZIP;
}
if((tmp = tmpfile()) == NULL) {
cli_dbgmsg("Can't generate tmpfile().\n");
BZ2_bzReadClose(&bzerror, bfd);
fclose(fs);
return CL_ETMPFILE;
}
fd = fileno(tmp);
if(!(buff = (char *) malloc(FILEBUFF))) {
cli_dbgmsg("cli_scanbzip(): unable to malloc(%d)\n", FILEBUFF);
fclose(tmp);
fclose(fs);
BZ2_bzReadClose(&bzerror, bfd);
return CL_EMEM;
}
while((bytes = BZ2_bzRead(&bzerror, bfd, buff, FILEBUFF)) > 0) {
size += bytes;
if(limits)
if(limits->maxfilesize && (size + FILEBUFF > limits->maxfilesize)) {
cli_dbgmsg("Bzip2->desc(%d): Size exceeded (stopped at %ld, max: %ld)\n", desc, size, limits->maxfilesize);
/* ret = CL_EMAXSIZE; */
break;
}
if(cli_writen(fd, buff, bytes) != bytes) {
cli_dbgmsg("Bzip2 -> Can't write() file.\n");
BZ2_bzReadClose(&bzerror, bfd);
fclose(tmp);
free(buff);
fclose(fs);
return CL_EGZIP;
}
}
free(buff);
BZ2_bzReadClose(&bzerror, bfd);
if(fsync(fd) == -1) {
cli_dbgmsg("fsync() failed for descriptor %d\n", fd);
fclose(tmp);
fclose(fs);
return CL_EFSYNC;
}
lseek(fd, 0, SEEK_SET);
if((ret = cli_magic_scandesc(fd, virname, scanned, root, limits, options, reclev)) == CL_VIRUS ) {
cli_dbgmsg("Bzip2 -> Found %s virus.\n", *virname);
}
fclose(tmp);
fclose(fs);
return ret;
}
#endif
static int cli_scanmscomp(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
int fd, ret = CL_CLEAN;
FILE *tmp = NULL, *in;
cli_dbgmsg("in cli_scanmscomp()\n");
if((in = fdopen(dup(desc), "rb")) == NULL) {
cli_dbgmsg("Can't fdopen() descriptor %d.\n", desc);
return CL_EMSCOMP;
}
if((tmp = tmpfile()) == NULL) {
cli_dbgmsg("Can't generate tmpfile().\n");
fclose(in);
return CL_ETMPFILE;
}
if(cli_msexpand(in, tmp) == -1) {
cli_dbgmsg("msexpand failed.\n");
return CL_EMSCOMP;
}
fclose(in);
if(fflush(tmp)) {
cli_dbgmsg("fflush() failed\n");
fclose(tmp);
return CL_EFSYNC;
}
fd = fileno(tmp);
lseek(fd, 0, SEEK_SET);
if((ret = cli_magic_scandesc(fd, virname, scanned, root, limits, options, reclev)) == CL_VIRUS) {
cli_dbgmsg("MSCompress -> Found %s virus.\n", *virname);
fclose(tmp);
return CL_VIRUS;
}
fclose(tmp);
return ret;
}
static int cli_scandir(const char *dirname, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
DIR *dd;
struct dirent *dent;
struct stat statbuf;
char *fname;
if((dd = opendir(dirname)) != NULL) {
while((dent = readdir(dd))) {
if(dent->d_ino) {
if(strcmp(dent->d_name, ".") && strcmp(dent->d_name, "..")) {
/* build the full name */
fname = cli_calloc(strlen(dirname) + strlen(dent->d_name) + 2, sizeof(char));
sprintf(fname, "%s/%s", dirname, dent->d_name);
/* stat the file */
if(lstat(fname, &statbuf) != -1) {
if(S_ISDIR(statbuf.st_mode) && !S_ISLNK(statbuf.st_mode)) {
if (cli_scandir(fname, virname, scanned, root, limits, options, reclev) == CL_VIRUS) {
free(fname);
closedir(dd);
return CL_VIRUS;
}
} else
if(S_ISREG(statbuf.st_mode))
if(cli_scanfile(fname, virname, scanned, root, limits, options, reclev) == CL_VIRUS) {
free(fname);
closedir(dd);
return CL_VIRUS;
}
}
free(fname);
}
}
}
} else {
cli_errmsg("ScanDir -> Can't open directory %s.\n", dirname);
return CL_EOPEN;
}
closedir(dd);
return 0;
}
static int cli_vba_scandir(const char *dirname, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
int ret = CL_CLEAN, i, fd, data_len;
vba_project_t *vba_project;
DIR *dd;
struct dirent *dent;
struct stat statbuf;
char *fname, *fullname;
unsigned char *data;
cli_dbgmsg("VBA scan dir: %s\n", dirname);
if((vba_project = (vba_project_t *) vba56_dir_read(dirname))) {
for(i = 0; i < vba_project->count; i++) {
fullname = (char *) cli_malloc(strlen(vba_project->dir) + strlen(vba_project->name[i]) + 2);
sprintf(fullname, "%s/%s", vba_project->dir, vba_project->name[i]);
fd = open(fullname, O_RDONLY);
if(fd == -1) {
cli_errmsg("Scan->OLE2 -> Can't open file %s\n", fullname);
free(fullname);
ret = CL_EOPEN;
break;
}
free(fullname);
cli_dbgmsg("decompress VBA project '%s'\n", vba_project->name[i]);
data = (unsigned char *) vba_decompress(fd, vba_project->offset[i], &data_len);
close(fd);
if(!data) {
cli_dbgmsg("WARNING: VBA project '%s' decompressed to NULL\n", vba_project->name[i]);
} else {
if(cl_scanbuff(data, data_len, virname, root) == CL_VIRUS) {
free(data);
ret = CL_VIRUS;
break;
}
free(data);
}
}
for(i = 0; i < vba_project->count; i++)
free(vba_project->name[i]);
free(vba_project->name);
free(vba_project->dir);
free(vba_project->offset);
free(vba_project);
} else if ((vba_project = (vba_project_t *) wm_dir_read(dirname))) {
for (i = 0; i < vba_project->count; i++) {
fullname = (char *) cli_malloc(strlen(vba_project->dir) + strlen(vba_project->name[i]) + 2);
sprintf(fullname, "%s/%s", vba_project->dir, vba_project->name[i]);
fd = open(fullname, O_RDONLY);
if(fd == -1) {
cli_errmsg("Scan->OLE2 -> Can't open file %s\n", fullname);
free(fullname);
ret = CL_EOPEN;
break;
}
free(fullname);
cli_dbgmsg("decompress WM project '%s' macro:%d key:%d\n", vba_project->name[i], i, vba_project->key[i]);
data = (unsigned char *) wm_decrypt_macro(fd, vba_project->offset[i], vba_project->length[i], vba_project->key[i]);
close(fd);
if(!data) {
cli_dbgmsg("WARNING: WM project '%s' macro %d decrypted to NULL\n", vba_project->name[i], i);
} else {
if(cl_scanbuff(data, vba_project->length[i], virname, root) == CL_VIRUS) {
free(data);
ret = CL_VIRUS;
break;
}
free(data);
}
}
for(i = 0; i < vba_project->count; i++)
free(vba_project->name[i]);
free(vba_project->key);
free(vba_project->length);
free(vba_project->offset);
free(vba_project->name);
free(vba_project->dir);
free(vba_project);
}
if(ret != CL_CLEAN)
return ret;
if((dd = opendir(dirname)) != NULL) {
while((dent = readdir(dd))) {
if(dent->d_ino) {
if(strcmp(dent->d_name, ".") && strcmp(dent->d_name, "..")) {
/* build the full name */
fname = cli_calloc(strlen(dirname) + strlen(dent->d_name) + 2, sizeof(char));
sprintf(fname, "%s/%s", dirname, dent->d_name);
/* stat the file */
if(lstat(fname, &statbuf) != -1) {
if(S_ISDIR(statbuf.st_mode) && !S_ISLNK(statbuf.st_mode))
if (cli_vba_scandir(fname, virname, scanned, root, limits, options, reclev) == CL_VIRUS) {
ret = CL_VIRUS;
free(fname);
break;
}
}
free(fname);
}
}
}
} else {
cli_errmsg("ScanDir -> Can't open directory %s.\n", dirname);
return CL_EOPEN;
}
closedir(dd);
return ret;
}
static int cli_scanole2(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
const char *tmpdir;
char *dir;
int ret = CL_CLEAN;
cli_dbgmsg("in cli_scanole2()\n");
tmpdir = getenv("TMPDIR");
if(tmpdir == NULL)
#ifdef P_tmpdir
tmpdir = P_tmpdir;
#else
tmpdir = "/tmp";
#endif
/* generate the temporary directory */
dir = cl_gentemp(tmpdir);
if(mkdir(dir, 0700)) {
cli_errmsg("ScanOLE2 -> Can't create temporary directory %s\n", dir);
return CL_ETMPDIR;
}
if((ret = cli_ole2_extract(desc, dir))) {
cli_errmsg("ScanOLE2 -> %s\n", cl_strerror(ret));
cli_rmdirs(dir);
free(dir);
return ret;
}
if((ret = cli_vba_scandir(dir, virname, scanned, root, limits, options, reclev)) != CL_VIRUS) {
if(cli_scandir(dir, virname, scanned, root, limits, options, reclev) == CL_VIRUS) {
ret = CL_VIRUS;
}
}
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_scanmail(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
const char *tmpdir;
char *dir;
int ret;
cli_dbgmsg("Starting cli_scanmail(), reclev %d\n", *reclev);
if(*reclev > 5) /* FIXME: a temporary workaround */
return CL_CLEAN;
tmpdir = getenv("TMPDIR");
if(tmpdir == NULL)
#ifdef P_tmpdir
tmpdir = P_tmpdir;
#else
tmpdir = "/tmp";
#endif
/* generate the temporary directory */
dir = cl_gentemp(tmpdir);
if(mkdir(dir, 0700)) {
cli_errmsg("ScanMail -> Can't create temporary directory %s\n", dir);
return CL_ETMPDIR;
}
/*
* Extract the attachments into the temporary directory
*/
ret = cl_mbox(dir, desc);
/* FIXME: check mbox return code */
ret = cli_scandir(dir, virname, scanned, root, limits, options, reclev);
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_magic_scandesc(int desc, const char **virname, long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
char magic[MAGIC_BUFFER_SIZE+1];
int ret = CL_CLEAN;
int bread = 0;
cli_file_t type;
if(!root) {
cli_errmsg("root == NULL\n");
return -1;
}
if(!options) { /* raw mode (stdin, etc.) */
if((ret = cli_scandesc(desc, virname, scanned, root) == CL_VIRUS))
cli_dbgmsg("%s virus found in descriptor %d.\n", *virname, desc);
return ret;
}
if(SCAN_ARCHIVE && limits && limits->maxreclevel)
if(*reclev > limits->maxreclevel)
/* return CL_EMAXREC; */
return CL_CLEAN;
(*reclev)++;
lseek(desc, 0, SEEK_SET);
bread = read(desc, magic, MAGIC_BUFFER_SIZE);
magic[MAGIC_BUFFER_SIZE] = '\0';
lseek(desc, 0, SEEK_SET);
if (bread != MAGIC_BUFFER_SIZE) {
/* short read: No need to do magic */
(*reclev)--;
return ret;
}
type = cli_filetype(magic, bread);
switch(type) {
case CL_DOSEXE:
/* temporarily the return code is ignored */
cli_scanpe(desc, virname, scanned, root, limits, options, reclev);
break;
case CL_RARFILE:
if(!DISABLE_RAR && SCAN_ARCHIVE && !cli_scanrar_inuse)
ret = cli_scanrar(desc, virname, scanned, root, limits, options, reclev);
break;
case CL_ZIPFILE:
if(SCAN_ARCHIVE)
ret = cli_scanzip(desc, virname, scanned, root, limits, options, reclev);
break;
case CL_GZFILE:
if(SCAN_ARCHIVE)
ret = cli_scangzip(desc, virname, scanned, root, limits, options, reclev);
break;
case CL_BZFILE:
#ifdef HAVE_BZLIB_H
if(SCAN_ARCHIVE)
ret = cli_scanbzip(desc, virname, scanned, root, limits, options, reclev);
#endif
break;
case CL_MSCFILE:
if(SCAN_ARCHIVE)
ret = cli_scanmscomp(desc, virname, scanned, root, limits, options, reclev);
break;
case CL_MAILFILE:
if(SCAN_MAIL)
ret = cli_scanmail(desc, virname, scanned, root, limits, options, reclev);
break;
case CL_OLE2FILE:
if(SCAN_OLE2)
ret = cli_scanole2(desc, virname, scanned, root, limits, options, reclev);
break;
case CL_DATAFILE:
/* it could be a false positive and a standard DOS .COM file */
{
struct stat s;
if(fstat(desc, &s) == 0 && S_ISREG(s.st_mode) && s.st_size < 65536)
type = CL_UNKNOWN_TYPE;
}
case CL_UNKNOWN_TYPE:
break;
}
(*reclev)--;
if(type != CL_DATAFILE && ret != CL_VIRUS) { /* scan the raw file */
lseek(desc, 0, SEEK_SET); /* If archive scan didn't rewind desc */
if(cli_scandesc(desc, virname, scanned, root) == CL_VIRUS) {
cli_dbgmsg("%s virus found in descriptor %d.\n", *virname, desc);
return CL_VIRUS;
}
}
return ret;
}
int cl_scandesc(int desc, const char **virname, unsigned long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options)
{
int reclev = 0;
return cli_magic_scandesc(desc, virname, scanned, root, limits, options, &reclev);
}
static int cli_scanfile(const char *filename, const char **virname, unsigned long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options, int *reclev)
{
int fd, ret;
/* internal version of cl_scanfile with reclev preserved */
if((fd = open(filename, O_RDONLY)) == -1)
return CL_EOPEN;
ret = cli_magic_scandesc(fd, virname, scanned, root, limits, options, reclev);
close(fd);
return ret;
}
int cl_scanfile(const char *filename, const char **virname, unsigned long int *scanned, const struct cl_node *root, const struct cl_limits *limits, int options)
{
int fd, ret;
if((fd = open(filename, O_RDONLY)) == -1)
return CL_EOPEN;
ret = cl_scandesc(fd, virname, scanned, root, limits, options);
close(fd);
return ret;
}