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

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/*
* Copyright (C) 2007-2008 Sourcefire, Inc.
*
* Authors: Tomasz Kojm
*
* 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.
*/
#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#include <fcntl.h>
#ifndef C_WINDOWS
#include <dirent.h>
#include <netinet/in.h>
#endif
#if HAVE_MMAP
#if HAVE_SYS_MMAN_H
#include <sys/mman.h>
#else /* HAVE_SYS_MMAN_H */
#undef HAVE_MMAP
#endif
#endif
#ifndef O_BINARY
#define O_BINARY 0
#endif
#define DCONF_ARCH ctx->dconf->archive
#define DCONF_DOC ctx->dconf->doc
#define DCONF_MAIL ctx->dconf->mail
#define DCONF_OTHER ctx->dconf->other
#include "clamav.h"
#include "others.h"
#include "dconf.h"
#include "scanners.h"
#include "matcher-ac.h"
#include "matcher-bm.h"
#include "matcher.h"
#include "ole2_extract.h"
#include "vba_extract.h"
#include "msexpand.h"
#include "mbox.h"
#include "chmunpack.h"
#include "pe.h"
#include "elf.h"
#include "filetypes.h"
#include "htmlnorm.h"
#include "untar.h"
#include "special.h"
#include "binhex.h"
/* #include "uuencode.h" */
#include "tnef.h"
#include "sis.h"
#include "pdf.h"
#include "str.h"
#include "mspack.h"
#include "cab.h"
#include "rtf.h"
#include "unarj.h"
#include "nulsft.h"
#include "autoit.h"
#include "textnorm.h"
#include <zlib.h>
#include "unzip.h"
#include "dlp.h"
#ifdef HAVE_BZLIB_H
#include <bzlib.h>
#endif
#ifdef ENABLE_UNRAR
#include "libclamunrar_iface/unrar_iface.h"
#endif
#if defined(HAVE_READDIR_R_3) || defined(HAVE_READDIR_R_2)
#include <limits.h>
#include <stddef.h>
#endif
static int cli_scanfile(const char *filename, cli_ctx *ctx);
static int cli_scandir(const char *dirname, cli_ctx *ctx, cli_file_t container)
{
DIR *dd;
struct dirent *dent;
#if defined(HAVE_READDIR_R_3) || defined(HAVE_READDIR_R_2)
union {
struct dirent d;
char b[offsetof(struct dirent, d_name) + NAME_MAX + 1];
} result;
#endif
struct stat statbuf;
char *fname;
int fd, ret = CL_CLEAN;
cli_file_t ftype;
if((dd = opendir(dirname)) != NULL) {
#ifdef HAVE_READDIR_R_3
while(!readdir_r(dd, &result.d, &dent) && dent) {
#elif defined(HAVE_READDIR_R_2)
while((dent = (struct dirent *) readdir_r(dd, &result.d))) {
#else
while((dent = readdir(dd))) {
#endif
#if (!defined(C_INTERIX)) && (!defined(C_WINDOWS))
if(dent->d_ino)
#endif
{
if(strcmp(dent->d_name, ".") && strcmp(dent->d_name, "..")) {
/* build the full name */
fname = cli_malloc(strlen(dirname) + strlen(dent->d_name) + 2);
if(!fname) {
closedir(dd);
return CL_EMEM;
}
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, ctx, container) == CL_VIRUS) {
free(fname);
closedir(dd);
return CL_VIRUS;
}
} else {
if(S_ISREG(statbuf.st_mode)) {
if(cli_scanfile(fname, ctx) == CL_VIRUS) {
free(fname);
closedir(dd);
return CL_VIRUS;
}
if(container == CL_TYPE_MAIL) {
fd = open(fname, O_RDONLY|O_BINARY);
if(fd == -1) {
cli_warnmsg("Cannot open file %s: %s, mode: %x\n", fname, strerror(errno), statbuf.st_mode);
free(fname);
continue;
}
ftype = cli_filetype2(fd, ctx->engine);
if(ftype >= CL_TYPE_TEXT_ASCII && ftype <= CL_TYPE_TEXT_UTF16BE) {
lseek(fd, 0, SEEK_SET);
ret = cli_scandesc(fd, ctx, CL_TYPE_MAIL, 0, NULL, AC_SCAN_VIR);
}
close(fd);
if(ret == CL_VIRUS) {
free(fname);
closedir(dd);
return CL_VIRUS;
}
}
}
}
}
free(fname);
}
}
}
} else {
cli_dbgmsg("cli_scandir: Can't open directory %s.\n", dirname);
return CL_EOPEN;
}
closedir(dd);
return CL_CLEAN;
}
#ifdef ENABLE_UNRAR
static int cli_unrar_scanmetadata(int desc, unrar_metadata_t *metadata, cli_ctx *ctx, unsigned int files, uint32_t* sfx_check)
{
int ret = CL_SUCCESS;
struct cli_meta_node* mdata;
if(files == 1 && sfx_check) {
if(*sfx_check == metadata->crc)
return CL_BREAK;/* break extract loop */
else
*sfx_check = metadata->crc;
}
cli_dbgmsg("RAR: %s, crc32: 0x%x, encrypted: %u, compressed: %u, normal: %u, method: %u, ratio: %u\n",
metadata->filename, metadata->crc, metadata->encrypted, (unsigned int) metadata->pack_size,
(unsigned int) metadata->unpack_size, metadata->method,
metadata->pack_size ? (unsigned int) (metadata->unpack_size / metadata->pack_size) : 0);
/* Scan metadata */
mdata = ctx->engine->rar_mlist;
if(mdata) do {
if(mdata->encrypted != metadata->encrypted)
continue;
if(mdata->crc32 && (unsigned int) mdata->crc32 != metadata->crc)
continue;
if(mdata->csize > 0 && (unsigned int) mdata->csize != metadata->pack_size)
continue;
if(mdata->size >= 0 && (unsigned int) mdata->size != metadata->unpack_size)
continue;
if(mdata->method >= 0 && mdata->method != metadata->method)
continue;
if(mdata->fileno && mdata->fileno != files)
continue;
if(mdata->maxdepth && ctx->recursion > mdata->maxdepth)
continue;
if(mdata->filename && !cli_matchregex(metadata->filename, mdata->filename))
continue;
break; /* matched */
} while((mdata = mdata->next));
if(mdata) {
*ctx->virname = mdata->virname;
return CL_VIRUS;
}
if(DETECT_ENCRYPTED && metadata->encrypted) {
cli_dbgmsg("RAR: Encrypted files found in archive.\n");
lseek(desc, 0, SEEK_SET);
ret = cli_scandesc(desc, ctx, 0, 0, NULL, AC_SCAN_VIR);
if(ret != CL_VIRUS) {
*ctx->virname = "Encrypted.RAR";
return CL_VIRUS;
}
}
return ret;
}
static int cli_scanrar(int desc, cli_ctx *ctx, off_t sfx_offset, uint32_t *sfx_check)
{
int ret = CL_CLEAN;
unrar_metadata_t *metadata, *metadata_tmp;
char *dir;
unrar_state_t rar_state;
cli_dbgmsg("in scanrar()\n");
if(sfx_offset)
if(lseek(desc, sfx_offset, SEEK_SET) == -1)
return CL_EIO;
/* generate the temporary directory */
if(!(dir = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_dbgmsg("RAR: Can't create temporary directory %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
if((ret = unrar_open(desc, dir, &rar_state)) != UNRAR_OK) {
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
if(ret == UNRAR_PASSWD) {
cli_dbgmsg("RAR: Encrypted main header\n");
if(DETECT_ENCRYPTED) {
lseek(desc, 0, SEEK_SET);
ret = cli_scandesc(desc, ctx, 0, 0, NULL, AC_SCAN_VIR);
if(ret != CL_VIRUS)
*ctx->virname = "Encrypted.RAR";
return CL_VIRUS;
}
return CL_CLEAN;
} if(ret == UNRAR_EMEM) {
return CL_EMEM;
} else {
return CL_ERAR;
}
}
do {
int rc;
rar_state.ofd = -1;
ret = unrar_extract_next_prepare(&rar_state,dir);
if(ret != UNRAR_OK) {
if(ret == UNRAR_BREAK)
ret = CL_BREAK;
else if(ret == UNRAR_EMEM)
ret = CL_EMEM;
else
ret = CL_ERAR;
break;
}
if((ret=cli_checklimits("RAR", ctx, rar_state.metadata_tail->unpack_size, rar_state.metadata_tail->pack_size, 0)!=CL_CLEAN)) {
free(rar_state.file_header->filename);
free(rar_state.file_header);
ret = CL_CLEAN;
continue;
}
ret = unrar_extract_next(&rar_state,dir);
if(ret == UNRAR_OK)
ret = CL_SUCCESS;
else if(ret == UNRAR_EMEM)
ret = CL_EMEM;
else
ret = CL_ERAR;
if(rar_state.ofd > 0) {
lseek(rar_state.ofd,0,SEEK_SET);
rc = cli_magic_scandesc(rar_state.ofd,ctx);
close(rar_state.ofd);
if(!cli_leavetemps_flag)
if (cli_unlink(rar_state.filename)) ret = CL_EIO;
if(rc == CL_VIRUS ) {
cli_dbgmsg("RAR: infected with %s\n",*ctx->virname);
ret = CL_VIRUS;
break;
}
}
if(ret == CL_SUCCESS)
ret = cli_unrar_scanmetadata(desc,rar_state.metadata_tail, ctx, rar_state.file_count, sfx_check);
} while(ret == CL_SUCCESS);
if(ret == CL_BREAK)
ret = CL_CLEAN;
metadata = metadata_tmp = rar_state.metadata;
if(cli_scandir(rar_state.comment_dir, ctx, 0) == CL_VIRUS)
ret = CL_VIRUS;
unrar_close(&rar_state);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
metadata = metadata_tmp;
while (metadata) {
metadata_tmp = metadata->next;
free(metadata->filename);
free(metadata);
metadata = metadata_tmp;
}
cli_dbgmsg("RAR: Exit code: %d\n", ret);
return ret;
}
#endif /* ENABLE_UNRAR */
static int cli_scanarj(int desc, cli_ctx *ctx, off_t sfx_offset, uint32_t *sfx_check)
{
int ret = CL_CLEAN, rc;
arj_metadata_t metadata;
char *dir;
cli_dbgmsg("in cli_scanarj()\n");
/* generate the temporary directory */
if(!(dir = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_dbgmsg("ARJ: Can't create temporary directory %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
if(sfx_offset)
lseek(desc, sfx_offset, SEEK_SET);
ret = cli_unarj_open(desc, dir);
if (ret != CL_SUCCESS) {
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
cli_dbgmsg("ARJ: Error: %s\n", cl_strerror(ret));
return ret;
}
metadata.filename = NULL;
do {
ret = cli_unarj_prepare_file(desc, dir, &metadata);
if (ret != CL_SUCCESS) {
break;
}
if ((ret = cli_checklimits("ARJ", ctx, metadata.orig_size, metadata.comp_size, 0))!=CL_CLEAN) {
ret = CL_SUCCESS;
continue;
}
ret = cli_unarj_extract_file(desc, dir, &metadata);
if (metadata.ofd >= 0) {
lseek(metadata.ofd, 0, SEEK_SET);
rc = cli_magic_scandesc(metadata.ofd, ctx);
close(metadata.ofd);
if (rc == CL_VIRUS) {
cli_dbgmsg("ARJ: infected with %s\n",*ctx->virname);
ret = CL_VIRUS;
break;
}
}
if (metadata.filename) {
free(metadata.filename);
metadata.filename = NULL;
}
} while(ret == CL_SUCCESS);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
if (metadata.filename) {
free(metadata.filename);
}
cli_dbgmsg("ARJ: Exit code: %d\n", ret);
if (ret == CL_BREAK)
ret = CL_CLEAN;
return ret;
}
static int cli_scangzip(int desc, cli_ctx *ctx)
{
int fd, bytes, ret = CL_CLEAN;
unsigned long int size = 0;
char *buff;
char *tmpname;
gzFile gd;
cli_dbgmsg("in cli_scangzip()\n");
if((gd = gzdopen(dup(desc), "rb")) == NULL) {
cli_dbgmsg("GZip: Can't open descriptor %d\n", desc);
return CL_EGZIP;
}
if((ret = cli_gentempfd(NULL, &tmpname, &fd))) {
cli_dbgmsg("GZip: Can't generate temporary file.\n");
gzclose(gd);
return ret;
}
if(!(buff = (char *) cli_malloc(FILEBUFF))) {
cli_dbgmsg("GZip: Unable to malloc %u bytes.\n", FILEBUFF);
gzclose(gd);
close(fd);
if(!cli_leavetemps_flag) {
if(cli_unlink(tmpname)) {
free(tmpname);
return CL_EIO;
}
}
return CL_EMEM;
}
while((bytes = gzread(gd, buff, FILEBUFF)) > 0) {
size += bytes;
if(cli_checklimits("GZip", ctx, size + FILEBUFF, 0, 0)!=CL_CLEAN)
break;
if(cli_writen(fd, buff, bytes) != bytes) {
cli_dbgmsg("GZip: Can't write to file.\n");
close(fd);
if(!cli_leavetemps_flag) {
if (cli_unlink(tmpname)) {
free(tmpname);
gzclose(gd);
free(buff);
return CL_EIO;
}
}
free(tmpname);
gzclose(gd);
free(buff);
return CL_EGZIP;
}
}
free(buff);
gzclose(gd);
if(ret == CL_VIRUS) {
close(fd);
if(!cli_leavetemps_flag)
if (cli_unlink(tmpname)) ret = CL_EIO;
free(tmpname);
return ret;
}
lseek(fd, 0, SEEK_SET);
if((ret = cli_magic_scandesc(fd, ctx)) == CL_VIRUS ) {
cli_dbgmsg("GZip: Infected with %s\n", *ctx->virname);
close(fd);
if(!cli_leavetemps_flag) {
if (cli_unlink(tmpname)) {
free(tmpname);
return CL_EIO;
}
}
free(tmpname);
return CL_VIRUS;
}
close(fd);
if(!cli_leavetemps_flag)
if (cli_unlink(tmpname)) ret = CL_EIO;
free(tmpname);
return ret;
}
#ifndef HAVE_BZLIB_H
static int cli_scanbzip(int desc, cli_ctx *ctx) {
cli_warnmsg("cli_scanbzip: bzip2 support not compiled in\n");
return CL_CLEAN;
}
#else
#ifdef NOBZ2PREFIX
#define BZ2_bzReadOpen bzReadOpen
#define BZ2_bzReadClose bzReadClose
#define BZ2_bzRead bzRead
#endif
static int cli_scanbzip(int desc, cli_ctx *ctx)
{
int fd, bytes, ret = CL_CLEAN, bzerror = 0;
short memlim = 0;
unsigned long int size = 0;
char *buff;
FILE *fs;
char *tmpname;
BZFILE *bfd;
if((fs = fdopen(dup(desc), "rb")) == NULL) {
cli_dbgmsg("Bzip: Can't open descriptor %d.\n", desc);
return CL_EBZIP;
}
if(ctx->limits)
if(ctx->limits->archivememlim)
memlim = 1;
if((bfd = BZ2_bzReadOpen(&bzerror, fs, 0, memlim, NULL, 0)) == NULL) {
cli_dbgmsg("Bzip: Can't initialize bzip2 library (descriptor: %d).\n", desc);
fclose(fs);
return CL_EBZIP;
}
if((ret = cli_gentempfd(NULL, &tmpname, &fd))) {
cli_dbgmsg("Bzip: Can't generate temporary file.\n");
BZ2_bzReadClose(&bzerror, bfd);
fclose(fs);
return ret;
}
if(!(buff = (char *) cli_malloc(FILEBUFF))) {
cli_dbgmsg("Bzip: Unable to malloc %u bytes.\n", FILEBUFF);
close(fd);
if(!cli_leavetemps_flag) {
if (cli_unlink(tmpname)) {
free(tmpname);
fclose(fs);
BZ2_bzReadClose(&bzerror, bfd);
return CL_EIO;
}
}
free(tmpname);
fclose(fs);
BZ2_bzReadClose(&bzerror, bfd);
return CL_EMEM;
}
while((bytes = BZ2_bzRead(&bzerror, bfd, buff, FILEBUFF)) > 0) {
size += bytes;
if(cli_checklimits("Bzip", ctx, size + FILEBUFF, 0, 0)!=CL_CLEAN)
break;
if(cli_writen(fd, buff, bytes) != bytes) {
cli_dbgmsg("Bzip: Can't write to file.\n");
BZ2_bzReadClose(&bzerror, bfd);
close(fd);
if(!cli_leavetemps_flag) {
if (cli_unlink(tmpname)) {
free(tmpname);
free(buff);
fclose(fs);
return CL_EIO;
}
}
free(tmpname);
free(buff);
fclose(fs);
return CL_EGZIP;
}
}
free(buff);
BZ2_bzReadClose(&bzerror, bfd);
if(ret == CL_VIRUS) {
close(fd);
if(!cli_leavetemps_flag)
if (cli_unlink(tmpname)) ret = CL_EIO;
free(tmpname);
fclose(fs);
return ret;
}
lseek(fd, 0, SEEK_SET);
if((ret = cli_magic_scandesc(fd, ctx)) == CL_VIRUS ) {
cli_dbgmsg("Bzip: Infected with %s\n", *ctx->virname);
}
close(fd);
if(!cli_leavetemps_flag)
if (cli_unlink(tmpname)) ret = CL_EIO;
free(tmpname);
fclose(fs);
return ret;
}
#endif
static int cli_scanszdd(int desc, cli_ctx *ctx)
{
int ofd, ret;
char *tmpname;
cli_dbgmsg("in cli_scanszdd()\n");
if((ret = cli_gentempfd(NULL, &tmpname, &ofd))) {
cli_dbgmsg("MSEXPAND: Can't generate temporary file/descriptor\n");
return ret;
}
lseek(desc, 0, SEEK_SET);
ret = cli_msexpand(desc, ofd, ctx);
if(ret != CL_SUCCESS) { /* CL_VIRUS or some error */
close(ofd);
if(!cli_leavetemps_flag)
if (cli_unlink(tmpname)) ret = CL_EIO;
free(tmpname);
return ret;
}
cli_dbgmsg("MSEXPAND: Decompressed into %s\n", tmpname);
lseek(ofd, 0, SEEK_SET);
ret = cli_magic_scandesc(ofd, ctx);
close(ofd);
if(!cli_leavetemps_flag)
if (cli_unlink(tmpname)) ret = CL_EIO;
free(tmpname);
return ret;
}
static int cli_scanmscab(int desc, cli_ctx *ctx, off_t sfx_offset)
{
char *tempname;
int ret;
unsigned int files = 0;
struct cab_archive cab;
struct cab_file *file;
cli_dbgmsg("in cli_scanmscab()\n");
if((ret = cab_open(desc, sfx_offset, &cab)))
return ret;
for(file = cab.files; file; file = file->next) {
files++;
if(cli_checklimits("CAB", ctx, file->length, 0, 0)!=CL_CLEAN)
continue;
if(!(tempname = cli_gentemp(NULL))) {
ret = CL_EMEM;
break;
}
cli_dbgmsg("CAB: Extracting file %s to %s, size %u\n", file->name, tempname, file->length);
if((ret = cab_extract(file, tempname)))
cli_dbgmsg("CAB: Failed to extract file: %s\n", cl_strerror(ret));
else
ret = cli_scanfile(tempname, ctx);
if(!cli_leavetemps_flag) {
if (cli_unlink(tempname)) {
free(tempname);
ret = CL_EIO;
break;
}
}
free(tempname);
if(ret == CL_VIRUS)
break;
}
cab_free(&cab);
return ret;
}
static int cli_vba_scandir(const char *dirname, cli_ctx *ctx, struct uniq *U)
{
int ret = CL_CLEAN, i, j, fd, data_len;
vba_project_t *vba_project;
DIR *dd;
struct dirent *dent;
#if defined(HAVE_READDIR_R_3) || defined(HAVE_READDIR_R_2)
union {
struct dirent d;
char b[offsetof(struct dirent, d_name) + NAME_MAX + 1];
} result;
#endif
struct stat statbuf;
char *fullname, vbaname[1024];
unsigned char *data;
char *hash;
uint32_t hashcnt;
cli_dbgmsg("VBADir: %s\n", dirname);
hashcnt = uniq_get(U, "_vba_project", 12, NULL);
while(hashcnt--) {
if(!(vba_project = (vba_project_t *)cli_vba_readdir(dirname, U, hashcnt))) continue;
for(i = 0; i < vba_project->count; i++) {
for(j = 0; (unsigned int)j < vba_project->colls[i]; j++) {
snprintf(vbaname, 1024, "%s/%s_%u", vba_project->dir, vba_project->name[i], j);
vbaname[sizeof(vbaname)-1] = '\0';
fd = open(vbaname, O_RDONLY|O_BINARY);
if(fd == -1) continue;
cli_dbgmsg("VBADir: Decompress VBA project '%s_%u'\n", vba_project->name[i], j);
data = (unsigned char *)cli_vba_inflate(fd, vba_project->offset[i], &data_len);
close(fd);
if(!data) {
cli_dbgmsg("VBADir: WARNING: VBA project '%s_%u' decompressed to NULL\n", vba_project->name[i], j);
} else {
/* cli_dbgmsg("Project content:\n%s", data); */
if(ctx->scanned)
*ctx->scanned += data_len / CL_COUNT_PRECISION;
if(cli_scanbuff(data, data_len, ctx, CL_TYPE_MSOLE2) == CL_VIRUS) {
free(data);
ret = CL_VIRUS;
break;
}
free(data);
}
}
}
free(vba_project->name);
free(vba_project->colls);
free(vba_project->dir);
free(vba_project->offset);
free(vba_project);
if (ret == CL_VIRUS) break;
}
if(ret == CL_CLEAN && (hashcnt = uniq_get(U, "powerpoint document", 19, &hash))) {
while(hashcnt--) {
snprintf(vbaname, 1024, "%s/%s_%u", dirname, hash, hashcnt);
vbaname[sizeof(vbaname)-1] = '\0';
fd = open(vbaname, O_RDONLY|O_BINARY);
if (fd == -1) continue;
if ((fullname = cli_ppt_vba_read(fd))) {
if(cli_scandir(fullname, ctx, 0) == CL_VIRUS) {
ret = CL_VIRUS;
}
if(!cli_leavetemps_flag)
cli_rmdirs(fullname);
free(fullname);
}
close(fd);
}
}
if (ret == CL_CLEAN && (hashcnt = uniq_get(U, "worddocument", 12, &hash))) {
while(hashcnt--) {
snprintf(vbaname, sizeof(vbaname), "%s/%s_%u", dirname, hash, hashcnt);
vbaname[sizeof(vbaname)-1] = '\0';
fd = open(vbaname, O_RDONLY|O_BINARY);
if (fd == -1) continue;
if (!(vba_project = (vba_project_t *)cli_wm_readdir(fd))) {
close(fd);
continue;
}
for (i = 0; i < vba_project->count; i++) {
cli_dbgmsg("VBADir: Decompress WM project macro:%d key:%d length:%d\n", i, vba_project->key[i], vba_project->length[i]);
data = (unsigned char *)cli_wm_decrypt_macro(fd, vba_project->offset[i], vba_project->length[i], vba_project->key[i]);
if(!data) {
cli_dbgmsg("VBADir: WARNING: WM project '%s' macro %d decrypted to NULL\n", vba_project->name[i], i);
} else {
cli_dbgmsg("Project content:\n%s", data);
if(ctx->scanned)
*ctx->scanned += vba_project->length[i] / CL_COUNT_PRECISION;
if(cli_scanbuff(data, vba_project->length[i], ctx, CL_TYPE_MSOLE2) == CL_VIRUS) {
free(data);
ret = CL_VIRUS;
break;
}
free(data);
}
}
close(fd);
free(vba_project->name);
free(vba_project->colls);
free(vba_project->dir);
free(vba_project->offset);
free(vba_project->key);
free(vba_project->length);
free(vba_project);
if(ret == CL_VIRUS) break;
}
}
if(ret != CL_CLEAN)
return ret;
/* Check directory for embedded OLE objects */
hashcnt = uniq_get(U, "_1_ole10native", 14, &hash);
while(hashcnt--) {
snprintf(vbaname, sizeof(vbaname), "%s/%s_%u", dirname, hash, hashcnt);
vbaname[sizeof(vbaname)-1] = '\0';
fd = open(vbaname, O_RDONLY|O_BINARY);
if (fd >= 0) {
ret = cli_scan_ole10(fd, ctx);
close(fd);
if(ret != CL_CLEAN)
return ret;
}
}
/* ACAB: since we now hash filenames and handle collisions we
* could avoid recursion by removing the block below and by
* flattening the paths in ole2_walk_property_tree (case 1) */
if((dd = opendir(dirname)) != NULL) {
#ifdef HAVE_READDIR_R_3
while(!readdir_r(dd, &result.d, &dent) && dent) {
#elif defined(HAVE_READDIR_R_2)
while((dent = (struct dirent *) readdir_r(dd, &result.d))) {
#else
while((dent = readdir(dd))) {
#endif
#if (!defined(C_INTERIX)) && (!defined(C_WINDOWS))
if(dent->d_ino)
#endif
{
if(strcmp(dent->d_name, ".") && strcmp(dent->d_name, "..")) {
/* build the full name */
fullname = cli_malloc(strlen(dirname) + strlen(dent->d_name) + 2);
if(!fullname) {
ret = CL_EMEM;
break;
}
sprintf(fullname, "%s/%s", dirname, dent->d_name);
/* stat the file */
if(lstat(fullname, &statbuf) != -1) {
if(S_ISDIR(statbuf.st_mode) && !S_ISLNK(statbuf.st_mode))
if (cli_vba_scandir(fullname, ctx, U) == CL_VIRUS) {
ret = CL_VIRUS;
free(fullname);
break;
}
}
free(fullname);
}
}
}
} else {
cli_dbgmsg("VBADir: Can't open directory %s.\n", dirname);
return CL_EOPEN;
}
closedir(dd);
return ret;
}
static int cli_scanhtml(int desc, cli_ctx *ctx)
{
char *tempname, fullname[1024];
int ret=CL_CLEAN, fd;
struct stat sb;
cli_dbgmsg("in cli_scanhtml()\n");
if(fstat(desc, &sb) == -1) {
cli_errmsg("cli_scanhtml: fstat() failed for descriptor %d\n", desc);
return CL_EIO;
}
/* Because HTML detection is FP-prone and html_normalise_fd() needs to
* mmap the file don't normalise files larger than 10 MB.
*/
if(sb.st_size > 10485760) {
cli_dbgmsg("cli_scanhtml: exiting (file larger than 10 MB)\n");
return CL_CLEAN;
}
if(!(tempname = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(tempname, 0700)) {
cli_errmsg("cli_scanhtml: Can't create temporary directory %s\n", tempname);
free(tempname);
return CL_ETMPDIR;
}
cli_dbgmsg("cli_scanhtml: using tempdir %s\n", tempname);
html_normalise_fd(desc, tempname, NULL, ctx->dconf);
snprintf(fullname, 1024, "%s/nocomment.html", tempname);
fd = open(fullname, O_RDONLY|O_BINARY);
if (fd >= 0) {
ret = cli_scandesc(fd, ctx, CL_TYPE_HTML, 0, NULL, AC_SCAN_VIR);
close(fd);
}
if(ret == CL_CLEAN && sb.st_size < 2097152) {
/* limit to 2 MB, we're not interesting in scanning large files in notags form */
/* TODO: don't even create notags if file is over 2 MB */
snprintf(fullname, 1024, "%s/notags.html", tempname);
fd = open(fullname, O_RDONLY|O_BINARY);
if(fd >= 0) {
ret = cli_scandesc(fd, ctx, CL_TYPE_HTML, 0, NULL, AC_SCAN_VIR);
close(fd);
}
}
if(ret == CL_CLEAN) {
snprintf(fullname, 1024, "%s/javascript", tempname);
fd = open(fullname, O_RDONLY|O_BINARY);
if(fd >= 0) {
ret = cli_scandesc(fd, ctx, CL_TYPE_HTML, 0, NULL, AC_SCAN_VIR);
close(fd);
}
}
if (ret == CL_CLEAN) {
snprintf(fullname, 1024, "%s/rfc2397", tempname);
ret = cli_scandir(fullname, ctx, 0);
}
if(!cli_leavetemps_flag)
cli_rmdirs(tempname);
free(tempname);
return ret;
}
static int cli_scanscript(int desc, cli_ctx *ctx)
{
unsigned char buff[FILEBUFF];
unsigned char* normalized;
struct text_norm_state state;
struct stat sb;
char *tmpname = NULL;
int ofd = -1, ret;
ssize_t nread;
const struct cli_matcher *root = ctx->engine->root[7];
uint32_t maxpatlen = root ? root->maxpatlen : 0;
cli_dbgmsg("in cli_scanscript()\n");
if(fstat(desc, &sb) == -1) {
cli_errmsg("cli_scanscript: fstat() failed for descriptor %d\n", desc);
return CL_EIO;
}
/* don't normalize files that are too large */
if(sb.st_size > 524288) {
cli_dbgmsg("cli_scanscript: exiting (file larger than 400 kB)\n");
return CL_CLEAN;
}
/* dump to disk only if explicitly asked to,
* otherwise we can process just in-memory */
if(cli_leavetemps_flag) {
if((ret = cli_gentempfd(NULL, &tmpname, &ofd))) {
cli_dbgmsg("cli_scanscript: Can't generate temporary file/descriptor\n");
return ret;
}
}
if(!(normalized = cli_malloc(SCANBUFF + maxpatlen))) {
cli_dbgmsg("cli_scanscript: Unable to malloc %u bytes\n", SCANBUFF);
return CL_EMEM;
}
text_normalize_init(&state, normalized, SCANBUFF + maxpatlen);
ret = CL_CLEAN;
do {
nread = cli_readn(desc, buff, sizeof(buff));
if(nread <= 0 || state.out_pos + nread > state.out_len) {
/* flush if error/EOF, or too little buffer space left */
if((ofd != -1) && (write(ofd, state.out, state.out_pos) == -1)) {
cli_errmsg("cli_scanscript: can't write to file %s\n",tmpname);
close(ofd);
ofd = -1;
/* we can continue to scan in memory */
}
/* when we flush the buffer also scan */
if(cli_scanbuff(state.out, state.out_pos, ctx, CL_TYPE_TEXT_ASCII) == CL_VIRUS) {
ret = CL_VIRUS;
break;
}
/* carry over maxpatlen from previous buffer */
if (state.out_pos > maxpatlen)
memcpy(state.out, state.out + state.out_pos - maxpatlen, maxpatlen);
text_normalize_reset(&state);
state.out_pos = maxpatlen;
}
if(nread > 0 && (text_normalize_buffer(&state, buff, nread) != nread)) {
cli_dbgmsg("cli_scanscript: short read during normalizing\n");
}
/* used a do {}while() here, since we need to flush our buffers at the end,
* and using while(){} loop would mean code duplication */
} while (nread > 0);
if(cli_leavetemps_flag) {
free(tmpname);
close(ofd);
}
free(normalized);
return ret;
}
static int cli_scanhtml_utf16(int desc, cli_ctx *ctx)
{
char *tempname, buff[512], *decoded;
int ret = CL_CLEAN, fd, bytes;
cli_dbgmsg("in cli_scanhtml_utf16()\n");
if(!(tempname = cli_gentemp(NULL)))
return CL_EMEM;
if((fd = open(tempname, O_RDWR|O_CREAT|O_TRUNC|O_BINARY, S_IRWXU)) < 0) {
cli_errmsg("cli_scanhtml_utf16: Can't create file %s\n", tempname);
free(tempname);
return CL_EIO;
}
cli_dbgmsg("cli_scanhtml_utf16: using tempfile %s\n", tempname);
while((bytes = read(desc, buff, sizeof(buff))) > 0) {
decoded = cli_utf16toascii(buff, bytes);
if(decoded) {
if(write(fd, decoded, strlen(decoded)) == -1) {
cli_errmsg("cli_scanhtml_utf16: Can't write to file %s\n", tempname);
free(decoded);
cli_unlink(tempname);
free(tempname);
close(fd);
return CL_EIO;
}
free(decoded);
}
}
lseek(fd, 0, SEEK_SET);
ret = cli_scanhtml(fd, ctx);
close(fd);
if(!cli_leavetemps_flag) {
if (cli_unlink(tempname)) ret = CL_EIO;
} else
cli_dbgmsg("cli_scanhtml_utf16: Decoded HTML data saved in %s\n", tempname);
free(tempname);
return ret;
}
static int cli_scanole2(int desc, cli_ctx *ctx)
{
char *dir;
int ret = CL_CLEAN;
struct uniq *vba = NULL;
cli_dbgmsg("in cli_scanole2()\n");
if(ctx->limits && ctx->limits->maxreclevel && ctx->recursion >= ctx->limits->maxreclevel)
return CL_EMAXREC;
/* generate the temporary directory */
if(!(dir = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_dbgmsg("OLE2: Can't create temporary directory %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
ret = cli_ole2_extract(desc, dir, ctx, &vba);
if(ret!=CL_CLEAN && ret!=CL_VIRUS) {
cli_dbgmsg("OLE2: %s\n", cl_strerror(ret));
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
if (vba) {
ctx->recursion++;
ret = cli_vba_scandir(dir, ctx, vba);
uniq_free(vba);
if(ret != CL_VIRUS)
if(cli_scandir(dir, ctx, 0) == CL_VIRUS)
ret = CL_VIRUS;
ctx->recursion--;
}
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_scantar(int desc, cli_ctx *ctx, unsigned int posix)
{
char *dir;
int ret = CL_CLEAN;
cli_dbgmsg("in cli_scantar()\n");
/* generate temporary directory */
if(!(dir = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_errmsg("Tar: Can't create temporary directory %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
ret = cli_untar(dir, desc, posix, ctx);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_scanbinhex(int desc, cli_ctx *ctx)
{
char *dir;
int ret = CL_CLEAN;
cli_dbgmsg("in cli_scanbinhex()\n");
/* generate temporary directory */
if(!(dir = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_errmsg("Binhex: Can't create temporary directory %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
if((ret = cli_binhex(dir, desc)))
cli_dbgmsg("Binhex: %s\n", cl_strerror(ret));
else
ret = cli_scandir(dir, ctx, 0);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_scanmschm(int desc, cli_ctx *ctx)
{
int ret = CL_CLEAN, rc;
chm_metadata_t metadata;
char *dir;
cli_dbgmsg("in cli_scanmschm()\n");
/* generate the temporary directory */
if(!(dir = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_dbgmsg("CHM: Can't create temporary directory %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
ret = cli_chm_open(desc, dir, &metadata);
if (ret != CL_SUCCESS) {
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
cli_dbgmsg("CHM: Error: %s\n", cl_strerror(ret));
return ret;
}
do {
ret = cli_chm_prepare_file(desc, dir, &metadata);
if (ret != CL_SUCCESS) {
break;
}
ret = cli_chm_extract_file(desc, dir, &metadata);
if (ret == CL_SUCCESS) {
lseek(metadata.ofd, 0, SEEK_SET);
rc = cli_magic_scandesc(metadata.ofd, ctx);
close(metadata.ofd);
if (rc == CL_VIRUS) {
cli_dbgmsg("CHM: infected with %s\n",*ctx->virname);
ret = CL_VIRUS;
break;
}
}
} while(ret == CL_SUCCESS);
cli_chm_close(&metadata);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
cli_dbgmsg("CHM: Exit code: %d\n", ret);
if (ret == CL_BREAK)
ret = CL_CLEAN;
return ret;
}
static int cli_scanscrenc(int desc, cli_ctx *ctx)
{
char *tempname;
int ret = CL_CLEAN;
cli_dbgmsg("in cli_scanscrenc()\n");
if(!(tempname = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(tempname, 0700)) {
cli_dbgmsg("CHM: Can't create temporary directory %s\n", tempname);
free(tempname);
return CL_ETMPDIR;
}
if (html_screnc_decode(desc, tempname))
ret = cli_scandir(tempname, ctx, 0);
if(!cli_leavetemps_flag)
cli_rmdirs(tempname);
free(tempname);
return ret;
}
static int cli_scanriff(int desc, const char **virname)
{
int ret = CL_CLEAN;
if(cli_check_riff_exploit(desc) == 2) {
ret = CL_VIRUS;
*virname = "Exploit.W32.MS05-002";
}
return ret;
}
static int cli_scanjpeg(int desc, const char **virname)
{
int ret = CL_CLEAN;
if(cli_check_jpeg_exploit(desc) == 1) {
ret = CL_VIRUS;
*virname = "Exploit.W32.MS04-028";
}
return ret;
}
static int cli_scancryptff(int desc, cli_ctx *ctx)
{
int ret = CL_CLEAN, ndesc;
unsigned int length, i;
unsigned char *src = NULL, *dest = NULL;
char *tempfile;
struct stat sb;
if(fstat(desc, &sb) == -1) {
cli_errmsg("CryptFF: Can't fstat descriptor %d\n", desc);
return CL_EIO;
}
/* Skip the CryptFF file header */
if(lseek(desc, 0x10, SEEK_SET) < 0) {
cli_errmsg("CryptFF: Can't lseek descriptor %d\n", desc);
return ret;
}
length = sb.st_size - 0x10;
if((dest = (unsigned char *) cli_malloc(length)) == NULL) {
cli_dbgmsg("CryptFF: Can't allocate memory\n");
return CL_EMEM;
}
if((src = (unsigned char *) cli_malloc(length)) == NULL) {
cli_dbgmsg("CryptFF: Can't allocate memory\n");
free(dest);
return CL_EMEM;
}
if((unsigned int) read(desc, src, length) != length) {
cli_dbgmsg("CryptFF: Can't read from descriptor %d\n", desc);
free(dest);
free(src);
return CL_EIO;
}
for(i = 0; i < length; i++)
dest[i] = src[i] ^ (unsigned char) 0xff;
free(src);
if(!(tempfile = cli_gentemp(NULL))) {
free(dest);
return CL_EMEM;
}
if((ndesc = open(tempfile, O_RDWR|O_CREAT|O_TRUNC|O_BINARY, S_IRWXU)) < 0) {
cli_errmsg("CryptFF: Can't create file %s\n", tempfile);
free(dest);
free(tempfile);
return CL_EIO;
}
if(write(ndesc, dest, length) == -1) {
cli_dbgmsg("CryptFF: Can't write to descriptor %d\n", ndesc);
free(dest);
close(ndesc);
free(tempfile);
return CL_EIO;
}
free(dest);
lseek(ndesc, 0, SEEK_SET);
cli_dbgmsg("CryptFF: Scanning decrypted data\n");
if((ret = cli_magic_scandesc(ndesc, ctx)) == CL_VIRUS)
cli_dbgmsg("CryptFF: Infected with %s\n", *ctx->virname);
close(ndesc);
if(cli_leavetemps_flag)
cli_dbgmsg("CryptFF: Decompressed data saved in %s\n", tempfile);
else
if (cli_unlink(tempfile)) ret = CL_EIO;
free(tempfile);
return ret;
}
static int cli_scanpdf(int desc, cli_ctx *ctx, off_t offset)
{
int ret;
char *dir = cli_gentemp(NULL);
if(!dir)
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_dbgmsg("Can't create temporary directory for PDF file %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
ret = cli_pdf(dir, desc, ctx, offset);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_scantnef(int desc, cli_ctx *ctx)
{
int ret;
char *dir = cli_gentemp(NULL);
if(!dir)
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_dbgmsg("Can't create temporary directory for tnef file %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
ret = cli_tnef(dir, desc);
if(ret == CL_CLEAN)
ret = cli_scandir(dir, ctx, 0);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_scanuuencoded(int desc, cli_ctx *ctx)
{
int ret;
char *dir = cli_gentemp(NULL);
if(!dir)
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_dbgmsg("Can't create temporary directory for uuencoded file %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
ret = cli_uuencode(dir, desc);
if(ret == CL_CLEAN)
ret = cli_scandir(dir, ctx, 0);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_scanmail(int desc, cli_ctx *ctx)
{
char *dir;
int ret;
cli_dbgmsg("Starting cli_scanmail(), recursion = %u\n", ctx->recursion);
/* generate the temporary directory */
if(!(dir = cli_gentemp(NULL)))
return CL_EMEM;
if(mkdir(dir, 0700)) {
cli_dbgmsg("Mail: Can't create temporary directory %s\n", dir);
free(dir);
return CL_ETMPDIR;
}
/*
* Extract the attachments into the temporary directory
*/
if((ret = cli_mbox(dir, desc, ctx))) {
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
ret = cli_scandir(dir, ctx, CL_TYPE_MAIL);
if(!cli_leavetemps_flag)
cli_rmdirs(dir);
free(dir);
return ret;
}
static int cli_scan_structured(int desc, cli_ctx *ctx)
{
char buf[8192];
int result = 0;
unsigned int cc_count = 0;
unsigned int ssn_count = 0;
int done = 0;
const struct cl_limits *lim = NULL;
int (*ccfunc)(const unsigned char *buffer, int length);
int (*ssnfunc)(const unsigned char *buffer, int length);
if(ctx == NULL || ctx->limits == NULL)
return CL_ENULLARG;
lim = ctx->limits;
if(lim->min_cc_count == 1)
ccfunc = dlp_has_cc;
else
ccfunc = dlp_get_cc_count;
switch((ctx->options & CL_SCAN_STRUCTURED_SSN_NORMAL) | (ctx->options & CL_SCAN_STRUCTURED_SSN_STRIPPED)) {
case (CL_SCAN_STRUCTURED_SSN_NORMAL | CL_SCAN_STRUCTURED_SSN_STRIPPED):
if(lim->min_ssn_count == 1)
ssnfunc = dlp_has_ssn;
else
ssnfunc = dlp_get_ssn_count;
break;
case CL_SCAN_STRUCTURED_SSN_NORMAL:
if(lim->min_ssn_count == 1)
ssnfunc = dlp_has_normal_ssn;
else
ssnfunc = dlp_get_normal_ssn_count;
break;
case CL_SCAN_STRUCTURED_SSN_STRIPPED:
if(lim->min_ssn_count == 1)
ssnfunc = dlp_has_stripped_ssn;
else
ssnfunc = dlp_get_stripped_ssn_count;
break;
default:
ssnfunc = NULL;
}
while(!done && ((result = cli_readn(desc, buf, 8191)) > 0)) {
if((cc_count += ccfunc((const unsigned char *)buf, result)) >= lim->min_cc_count)
done = 1;
if(ssnfunc && ((ssn_count += ssnfunc((const unsigned char *)buf, result)) >= lim->min_ssn_count))
done = 1;
}
if(cc_count != 0 && cc_count >= lim->min_cc_count) {
cli_dbgmsg("cli_scan_structured: %u credit card numbers detected\n", cc_count);
*ctx->virname = "Structured.CreditCardNumber";
return CL_VIRUS;
}
if(ssn_count != 0 && ssn_count >= lim->min_ssn_count) {
cli_dbgmsg("cli_scan_structured: %u social security numbers detected\n", ssn_count);
*ctx->virname = "Structured.SSN";
return CL_VIRUS;
}
return CL_CLEAN;
}
static int cli_scanembpe(int desc, cli_ctx *ctx)
{
int fd, bytes, ret = CL_CLEAN;
unsigned long int size = 0;
char buff[512];
char *tmpname;
tmpname = cli_gentemp(NULL);
if(!tmpname)
return CL_EMEM;
if((fd = open(tmpname, O_RDWR|O_CREAT|O_TRUNC|O_BINARY, S_IRWXU)) < 0) {
cli_errmsg("cli_scanembpe: Can't create file %s\n", tmpname);
free(tmpname);
return CL_EIO;
}
while((bytes = read(desc, buff, sizeof(buff))) > 0) {
size += bytes;
if(cli_checklimits("cli_scanembpe", ctx, size + sizeof(buff), 0, 0)!=CL_CLEAN)
break;
if(cli_writen(fd, buff, bytes) != bytes) {
cli_dbgmsg("cli_scanembpe: Can't write to temporary file\n");
close(fd);
if(!cli_leavetemps_flag) {
if (cli_unlink(tmpname)) {
free(tmpname);
return CL_EIO;
}
}
free(tmpname);
return CL_EIO;
}
}
ctx->recursion++;
lseek(fd, 0, SEEK_SET);
if((ret = cli_magic_scandesc(fd, ctx)) == CL_VIRUS) {
cli_dbgmsg("cli_scanembpe: Infected with %s\n", *ctx->virname);
close(fd);
if(!cli_leavetemps_flag) {
if (cli_unlink(tmpname)) {
free(tmpname);
return CL_EIO;
}
}
free(tmpname);
return CL_VIRUS;
}
ctx->recursion--;
close(fd);
if(!cli_leavetemps_flag) {
if (cli_unlink(tmpname)) {
free(tmpname);
return CL_EIO;
}
}
free(tmpname);
/* intentionally ignore possible errors from cli_magic_scandesc */
return CL_CLEAN;
}
static int cli_scanraw(int desc, cli_ctx *ctx, cli_file_t type, uint8_t typercg, cli_file_t *dettype)
{
int ret = CL_CLEAN, nret = CL_CLEAN;
struct cli_matched_type *ftoffset = NULL, *fpt;
uint32_t lastzip, lastrar;
struct cli_exe_info peinfo;
unsigned int acmode = AC_SCAN_VIR, break_loop = 0;
if(typercg) switch(type) {
case CL_TYPE_TEXT_ASCII:
case CL_TYPE_MSEXE:
case CL_TYPE_ZIP:
case CL_TYPE_MSOLE2:
acmode |= AC_SCAN_FT;
default:
break;
}
if(lseek(desc, 0, SEEK_SET) < 0) {
cli_errmsg("cli_scanraw: lseek() failed\n");
return CL_EIO;
}
ret = cli_scandesc(desc, ctx, type == CL_TYPE_TEXT_ASCII ? 0 : type, 0, &ftoffset, acmode);
if(ret >= CL_TYPENO) {
/*
if(type == CL_TYPE_TEXT_ASCII) {
lseek(desc, 0, SEEK_SET);
nret = cli_scandesc(desc, ctx, 0, ret, 1, NULL);
if(nret == CL_VIRUS)
cli_dbgmsg("%s found in descriptor %d when scanning file type %u\n", *ctx->virname, desc, ret);
}
*/
if(nret != CL_VIRUS && (type == CL_TYPE_MSEXE || type == CL_TYPE_ZIP || type == CL_TYPE_MSOLE2)) {
lastzip = lastrar = 0xdeadbeef;
fpt = ftoffset;
while(fpt) {
switch(fpt->type) {
case CL_TYPE_RARSFX:
#ifdef ENABLE_UNRAR
if(SCAN_ARCHIVE && type == CL_TYPE_MSEXE && (DCONF_ARCH & ARCH_CONF_RAR)) {
cli_dbgmsg("RAR-SFX signature found at %u\n", (unsigned int) fpt->offset);
nret = cli_scanrar(desc, ctx, fpt->offset, &lastrar);
}
#endif
break;
case CL_TYPE_ZIPSFX:
if(SCAN_ARCHIVE && type == CL_TYPE_MSEXE && (DCONF_ARCH & ARCH_CONF_ZIP) && fpt->offset) {
cli_dbgmsg("ZIP-SFX signature found at %u\n", (unsigned int) fpt->offset);
nret = cli_unzip_single(desc, ctx, fpt->offset);
}
break;
case CL_TYPE_CABSFX:
if(SCAN_ARCHIVE && type == CL_TYPE_MSEXE && (DCONF_ARCH & ARCH_CONF_CAB)) {
cli_dbgmsg("CAB-SFX signature found at %u\n", (unsigned int) fpt->offset);
nret = cli_scanmscab(desc, ctx, fpt->offset);
}
break;
case CL_TYPE_ARJSFX:
if(SCAN_ARCHIVE && type == CL_TYPE_MSEXE && (DCONF_ARCH & ARCH_CONF_ARJ)) {
cli_dbgmsg("ARJ-SFX signature found at %u\n", (unsigned int) fpt->offset);
nret = cli_scanarj(desc, ctx, fpt->offset, &lastrar);
}
break;
case CL_TYPE_NULSFT:
if(SCAN_ARCHIVE && type == CL_TYPE_MSEXE && (DCONF_ARCH & ARCH_CONF_NSIS) && fpt->offset > 4) {
cli_dbgmsg("NSIS signature found at %u\n", (unsigned int) fpt->offset-4);
nret = cli_scannulsft(desc, ctx, fpt->offset - 4);
}
break;
case CL_TYPE_AUTOIT:
if(SCAN_ARCHIVE && type == CL_TYPE_MSEXE && (DCONF_ARCH & ARCH_CONF_AUTOIT)) {
cli_dbgmsg("AUTOIT signature found at %u\n", (unsigned int) fpt->offset);
nret = cli_scanautoit(desc, ctx, fpt->offset + 23);
}
break;
case CL_TYPE_PDF:
if(SCAN_PDF && (DCONF_DOC & DOC_CONF_PDF)) {
cli_dbgmsg("PDF signature found at %u\n", (unsigned int) fpt->offset);
nret = cli_scanpdf(desc, ctx, fpt->offset);
}
break;
case CL_TYPE_MSEXE:
if(SCAN_PE && ctx->dconf->pe && fpt->offset) {
cli_dbgmsg("PE signature found at %u\n", (unsigned int) fpt->offset);
memset(&peinfo, 0, sizeof(struct cli_exe_info));
peinfo.offset = fpt->offset;
lseek(desc, fpt->offset, SEEK_SET);
if(cli_peheader(desc, &peinfo) == 0) {
cli_dbgmsg("*** Detected embedded PE file ***\n");
if(peinfo.section)
free(peinfo.section);
lseek(desc, fpt->offset, SEEK_SET);
nret = cli_scanembpe(desc, ctx);
break_loop = 1; /* we can stop here and other
* embedded executables will
* be found recursively
* through the above call
*/
}
}
break;
default:
cli_warnmsg("cli_scanraw: Type %u not handled in fpt loop\n", fpt->type);
}
if(nret == CL_VIRUS || break_loop)
break;
fpt = fpt->next;
}
}
ctx->recursion++;
if(nret != CL_VIRUS) switch(ret) {
case CL_TYPE_HTML:
if(SCAN_HTML && type == CL_TYPE_TEXT_ASCII && (DCONF_DOC & DOC_CONF_HTML)) {
*dettype = CL_TYPE_HTML;
nret = cli_scanhtml(desc, ctx);
}
break;
case CL_TYPE_MAIL:
if(SCAN_MAIL && type == CL_TYPE_TEXT_ASCII && (DCONF_MAIL & MAIL_CONF_MBOX))
nret = cli_scanmail(desc, ctx);
break;
default:
break;
}
ctx->recursion--;
ret = nret;
}
while(ftoffset) {
fpt = ftoffset;
ftoffset = ftoffset->next;
free(fpt);
}
if(ret == CL_VIRUS)
cli_dbgmsg("%s found in descriptor %d\n", *ctx->virname, desc);
return ret;
}
int cli_magic_scandesc(int desc, cli_ctx *ctx)
{
int ret = CL_CLEAN;
cli_file_t type, dettype = 0;
struct stat sb;
uint8_t typercg = 1;
if(fstat(desc, &sb) == -1) {
cli_errmsg("magic_scandesc: Can't fstat descriptor %d\n", desc);
return CL_EIO;
}
if(sb.st_size <= 5) {
cli_dbgmsg("Small data (%u bytes)\n", (unsigned int) sb.st_size);
return CL_CLEAN;
}
if(!ctx->engine) {
cli_errmsg("CRITICAL: engine == NULL\n");
return CL_EMALFDB;
}
if(!ctx->options) { /* raw mode (stdin, etc.) */
cli_dbgmsg("Raw mode: No support for special files\n");
if((ret = cli_scandesc(desc, ctx, 0, 0, NULL, AC_SCAN_VIR)) == CL_VIRUS)
cli_dbgmsg("%s found in descriptor %d\n", *ctx->virname, desc);
return ret;
}
if(cli_updatelimits(ctx, sb.st_size)!=CL_CLEAN)
return CL_CLEAN;
if((SCAN_MAIL || SCAN_ARCHIVE) && ctx->limits && ctx->limits->maxreclevel && ctx->recursion > ctx->limits->maxreclevel) {
cli_dbgmsg("Archive recursion limit exceeded (level = %u).\n", ctx->recursion);
return CL_CLEAN;
}
lseek(desc, 0, SEEK_SET);
type = cli_filetype2(desc, ctx->engine);
if(type == CL_TYPE_ERROR) {
cli_dbgmsg("cli_magic_scandesc: cli_filetype2 returned CL_TYPE_ERROR\n");
return CL_EIO;
}
lseek(desc, 0, SEEK_SET);
if(type != CL_TYPE_IGNORED && ctx->engine->sdb) {
if((ret = cli_scanraw(desc, ctx, type, 0, &dettype)) == CL_VIRUS)
return CL_VIRUS;
lseek(desc, 0, SEEK_SET);
}
ctx->recursion++;
switch(type) {
case CL_TYPE_IGNORED:
break;
case CL_TYPE_RAR:
#ifdef ENABLE_UNRAR
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_RAR))
ret = cli_scanrar(desc, ctx, 0, NULL);
#else
cli_warnmsg("RAR code not compiled-in\n");
#endif
break;
case CL_TYPE_ZIP:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_ZIP))
ret = cli_unzip(desc, ctx);
break;
case CL_TYPE_GZ:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_GZ))
ret = cli_scangzip(desc, ctx);
break;
case CL_TYPE_BZ:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_BZ))
ret = cli_scanbzip(desc, ctx);
break;
case CL_TYPE_ARJ:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_ARJ))
ret = cli_scanarj(desc, ctx, 0, NULL);
break;
case CL_TYPE_NULSFT:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_NSIS))
ret = cli_scannulsft(desc, ctx, 0);
break;
case CL_TYPE_AUTOIT:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_AUTOIT))
ret = cli_scanautoit(desc, ctx, 23);
break;
case CL_TYPE_MSSZDD:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_SZDD))
ret = cli_scanszdd(desc, ctx);
break;
case CL_TYPE_MSCAB:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_CAB))
ret = cli_scanmscab(desc, ctx, 0);
break;
case CL_TYPE_HTML:
if(SCAN_HTML && (DCONF_DOC & DOC_CONF_HTML))
ret = cli_scanhtml(desc, ctx);
break;
case CL_TYPE_HTML_UTF16:
if(SCAN_HTML && (DCONF_DOC & DOC_CONF_HTML))
ret = cli_scanhtml_utf16(desc, ctx);
break;
case CL_TYPE_SCRIPT:
if((DCONF_DOC & DOC_CONF_SCRIPT) && dettype != CL_TYPE_HTML)
ret = cli_scanscript(desc, ctx);
break;
case CL_TYPE_RTF:
if(SCAN_ARCHIVE && (DCONF_DOC & DOC_CONF_RTF))
ret = cli_scanrtf(desc, ctx);
break;
case CL_TYPE_MAIL:
if(SCAN_MAIL && (DCONF_MAIL & MAIL_CONF_MBOX))
ret = cli_scanmail(desc, ctx);
break;
case CL_TYPE_TNEF:
if(SCAN_MAIL && (DCONF_MAIL & MAIL_CONF_TNEF))
ret = cli_scantnef(desc, ctx);
break;
case CL_TYPE_UUENCODED:
if(DCONF_OTHER & OTHER_CONF_UUENC)
ret = cli_scanuuencoded(desc, ctx);
break;
case CL_TYPE_MSCHM:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_CHM))
ret = cli_scanmschm(desc, ctx);
break;
case CL_TYPE_MSOLE2:
if(SCAN_OLE2 && (DCONF_ARCH & ARCH_CONF_OLE2))
ret = cli_scanole2(desc, ctx);
break;
case CL_TYPE_POSIX_TAR:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_TAR))
ret = cli_scantar(desc, ctx, 1);
break;
case CL_TYPE_OLD_TAR:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_TAR))
ret = cli_scantar(desc, ctx, 0);
break;
case CL_TYPE_BINHEX:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_BINHEX))
ret = cli_scanbinhex(desc, ctx);
break;
case CL_TYPE_SCRENC:
if(DCONF_OTHER & OTHER_CONF_SCRENC)
ret = cli_scanscrenc(desc, ctx);
break;
case CL_TYPE_RIFF:
if(SCAN_ALGO && (DCONF_OTHER & OTHER_CONF_RIFF))
ret = cli_scanriff(desc, ctx->virname);
break;
case CL_TYPE_GRAPHICS:
if(SCAN_ALGO && (DCONF_OTHER & OTHER_CONF_JPEG))
ret = cli_scanjpeg(desc, ctx->virname);
break;
case CL_TYPE_PDF: /* FIXMELIMITS: pdf should be an archive! */
if(SCAN_PDF && (DCONF_DOC & DOC_CONF_PDF))
ret = cli_scanpdf(desc, ctx, 0);
break;
case CL_TYPE_CRYPTFF:
if(DCONF_OTHER & OTHER_CONF_CRYPTFF)
ret = cli_scancryptff(desc, ctx);
break;
case CL_TYPE_ELF:
if(SCAN_ELF && ctx->dconf->elf)
ret = cli_scanelf(desc, ctx);
break;
case CL_TYPE_SIS:
if(SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_SIS))
ret = cli_scansis(desc, ctx);
break;
case CL_TYPE_BINARY_DATA:
ret = cli_check_mydoom_log(desc, ctx->virname);
break;
case CL_TYPE_TEXT_ASCII:
if(SCAN_STRUCTURED && (DCONF_OTHER & OTHER_CONF_DLP))
/* TODO: consider calling this from cli_scanscript() for
* a normalised text
*/
ret = cli_scan_structured(desc, ctx);
break;
default:
break;
}
ctx->recursion--;
if(ret == CL_VIRUS)
return CL_VIRUS;
if(type == CL_TYPE_ZIP && SCAN_ARCHIVE && (DCONF_ARCH & ARCH_CONF_ZIP)) {
if(sb.st_size > 1048576) {
cli_dbgmsg("cli_magic_scandesc: Not checking for embedded PEs (zip file > 1 MB)\n");
typercg = 0;
}
}
/* CL_TYPE_HTML: raw HTML files are not scanned, unless safety measure activated via DCONF */
if(type != CL_TYPE_IGNORED && (type != CL_TYPE_HTML || !(DCONF_DOC & DOC_CONF_HTML_SKIPRAW)) && !ctx->engine->sdb) {
if(cli_scanraw(desc, ctx, type, typercg, &dettype) == CL_VIRUS)
return CL_VIRUS;
}
ctx->recursion++;
lseek(desc, 0, SEEK_SET);
switch(type) {
case CL_TYPE_TEXT_ASCII:
case CL_TYPE_TEXT_UTF16BE:
case CL_TYPE_TEXT_UTF16LE:
case CL_TYPE_TEXT_UTF8:
if((DCONF_DOC & DOC_CONF_SCRIPT) && dettype != CL_TYPE_HTML)
ret = cli_scanscript(desc, ctx);
break;
/* Due to performance reasons all executables were first scanned
* in raw mode. Now we will try to unpack them
*/
case CL_TYPE_MSEXE:
if(SCAN_PE && ctx->dconf->pe)
ret = cli_scanpe(desc, ctx);
break;
default:
break;
}
ctx->recursion--;
switch(ret) {
case CL_EFORMAT:
case CL_EMAXREC:
case CL_EMAXSIZE:
case CL_EMAXFILES:
cli_dbgmsg("Descriptor[%d]: %s\n", desc, cl_strerror(ret));
return CL_CLEAN;
default:
return ret;
}
}
int cl_scandesc(int desc, const char **virname, unsigned long int *scanned, const struct cl_engine *engine, const struct cl_limits *limits, unsigned int options)
{
cli_ctx ctx;
struct cl_limits l_limits;
int rc;
if(!limits) {
cli_errmsg("cl_scandesc: limits == NULL\n");
return CL_ENULLARG;
}
memset(&ctx, '\0', sizeof(cli_ctx));
ctx.engine = engine;
ctx.virname = virname;
ctx.scanned = scanned;
ctx.options = options;
ctx.found_possibly_unwanted = 0;
ctx.dconf = (struct cli_dconf *) engine->dconf;
ctx.limits = &l_limits;
memcpy(&l_limits, limits, sizeof(struct cl_limits));
rc = cli_magic_scandesc(desc, &ctx);
if(rc == CL_CLEAN && ctx.found_possibly_unwanted)
rc = CL_VIRUS;
return rc;
}
int cli_found_possibly_unwanted(cli_ctx* ctx)
{
if(ctx->virname) {
cli_dbgmsg("found Possibly Unwanted: %s\n",*ctx->virname);
if(ctx->options & CL_SCAN_HEURISTIC_PRECEDENCE) {
/* we found a heuristic match, don't scan further,
* but consider it a virus. */
cli_dbgmsg("cli_found_possibly_unwanted: CL_VIRUS\n");
return CL_VIRUS;
}
/* heuristic scan isn't taking precedence, keep scanning.
* If this is part of an archive, and
* we find a real malware we report that instead of the
* heuristic match */
ctx->found_possibly_unwanted = 1;
} else {
cli_warnmsg("cli_found_possibly_unwanted called, but virname is not set\n");
}
return CL_CLEAN;
}
static int cli_scanfile(const char *filename, cli_ctx *ctx)
{
int fd, ret;
/* internal version of cl_scanfile with arec/mrec preserved */
if((fd = open(filename, O_RDONLY|O_BINARY)) == -1)
return CL_EOPEN;
ret = cli_magic_scandesc(fd, ctx);
close(fd);
return ret;
}
int cl_scanfile(const char *filename, const char **virname, unsigned long int *scanned, const struct cl_engine *engine, const struct cl_limits *limits, unsigned int options)
{
int fd, ret;
if((fd = open(filename, O_RDONLY|O_BINARY)) == -1)
return CL_EOPEN;
ret = cl_scandesc(fd, virname, scanned, engine, limits, options);
close(fd);
return ret;
}
/*
Local Variables:
c-basic-offset: 4
End:
*/