/*
* Copyright (C) 2009 Sourcefire, Inc.
*
* Authors: Tomasz Kojm <tkojm@clamav.net>
*
* 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 <ctype.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "cltypes.h"
#include "others.h"
#include "cpio.h"
#include "scanners.h"
struct cpio_hdr_old {
uint16_t magic;
uint16_t dev;
uint16_t ino;
uint16_t mode;
uint16_t uid;
uint16_t gid;
uint16_t nlink;
uint16_t rdev;
uint16_t mtime[2];
uint16_t namesize;
uint16_t filesize[2];
};
struct cpio_hdr_odc {
char magic[6];
char dev[6];
char ino[6];
char mode[6];
char uid[6];
char gid[6];
char nlink[6];
char rdev[6];
char mtime[11];
char namesize[6];
char filesize[11];
};
struct cpio_hdr_newc {
char magic[6];
char ino[8];
char mode[8];
char uid[8];
char gid[8];
char nlink[8];
char mtime[8];
char filesize[8];
char devmajor[8];
char devminor[8];
char rdevmajor[8];
char rdevminor[8];
char namesize[8];
char check[8];
};
#define EC16(v, conv) (conv ? cbswap16(v) : v)
static void sanitname(char *name)
{
while(*name) {
if(!isascii(*name) || strchr("%\\\t\n\r", *name))
*name = '_';
name++;
}
}
int cli_scancpio_old(int fd, cli_ctx *ctx)
{
struct cpio_hdr_old hdr_old;
char name[513];
unsigned int file = 0, trailer = 0;
uint32_t filesize, namesize, hdr_namesize;
int ret, conv;
off_t pos;
while(read(fd, &hdr_old, sizeof(hdr_old)) == sizeof(hdr_old)) {
if(!hdr_old.magic && trailer)
return CL_SUCCESS;
if(hdr_old.magic == 070707) {
conv = 0;
} else if(hdr_old.magic == 0143561) {
conv = 1;
} else {
cli_dbgmsg("cli_scancpio_old: Invalid magic number\n");
return CL_EFORMAT;
}
cli_dbgmsg("CPIO: -- File %u --\n", ++file);
if(hdr_old.namesize) {
hdr_namesize = EC16(hdr_old.namesize, conv);
namesize = MIN(sizeof(name), hdr_namesize);
if(read(fd, name, namesize) != namesize) {
cli_dbgmsg("cli_scancpio_old: Can't read file name\n");
return CL_EFORMAT;
}
name[namesize - 1] = 0;
sanitname(name);
cli_dbgmsg("CPIO: Name: %s\n", name);
if(!strcmp(name, "TRAILER!!!"))
trailer = 1;
if(namesize < hdr_namesize) {
if(hdr_namesize % 2)
hdr_namesize++;
lseek(fd, hdr_namesize - namesize, SEEK_CUR);
} else if(hdr_namesize % 2)
lseek(fd, 1, SEEK_CUR);
}
filesize = (uint32_t) (EC16(hdr_old.filesize[0], conv) << 16 | EC16(hdr_old.filesize[1], conv));
cli_dbgmsg("CPIO: Filesize: %u\n", filesize);
if(!filesize)
continue;
pos = lseek(fd, 0, SEEK_CUR);
if((EC16(hdr_old.mode, conv) & 0170000) != 0100000) {
cli_dbgmsg("CPIO: Not a regular file, skipping\n");
} else {
ret = cli_checklimits("cli_scancpio_old", ctx, filesize, 0, 0);
if(ret == CL_EMAXFILES) {
return ret;
} else if(ret == CL_SUCCESS) {
ret = cli_dumpscan(fd, 0, filesize, ctx);
if(ret == CL_VIRUS)
return ret;
}
}
if(filesize % 2)
filesize++;
lseek(fd, pos + filesize, SEEK_SET);
}
return CL_CLEAN;
}
int cli_scancpio_odc(int fd, cli_ctx *ctx)
{
struct cpio_hdr_odc hdr_odc;
char name[513], buff[12];
unsigned int file = 0, trailer = 0;
uint32_t filesize, namesize, hdr_namesize;
int ret;
off_t pos;
while(read(fd, &hdr_odc, sizeof(hdr_odc)) == sizeof(hdr_odc)) {
if(!hdr_odc.magic[0] && trailer)
return CL_SUCCESS;
if(strncmp(hdr_odc.magic, "070707", 6)) {
cli_dbgmsg("cli_scancpio_odc: Invalid magic string\n");
return CL_EFORMAT;
}
cli_dbgmsg("CPIO: -- File %u --\n", ++file);
strncpy(buff, hdr_odc.namesize, 6);
buff[6] = 0;
if(sscanf(buff, "%o", &hdr_namesize) != 1) {
cli_dbgmsg("cli_scancpio_odc: Can't convert name size\n");
return CL_EFORMAT;
}
if(hdr_namesize) {
namesize = MIN(sizeof(name), hdr_namesize);
if(read(fd, name, namesize) != namesize) {
cli_dbgmsg("cli_scancpio_odc: Can't read file name\n");
return CL_EFORMAT;
}
name[namesize - 1] = 0;
sanitname(name);
cli_dbgmsg("CPIO: Name: %s\n", name);
if(!strcmp(name, "TRAILER!!!"))
trailer = 1;
if(namesize < hdr_namesize)
lseek(fd, hdr_namesize - namesize, SEEK_CUR);
}
strncpy(buff, hdr_odc.filesize, 11);
buff[11] = 0;
if(sscanf(buff, "%o", &filesize) != 1) {
cli_dbgmsg("cli_scancpio_odc: Can't convert file size\n");
return CL_EFORMAT;
}
cli_dbgmsg("CPIO: Filesize: %u\n", filesize);
if(!filesize)
continue;
pos = lseek(fd, 0, SEEK_CUR);
ret = cli_checklimits("cli_scancpio_odc", ctx, filesize, 0, 0);
if(ret == CL_EMAXFILES) {
return ret;
} else if(ret == CL_SUCCESS) {
ret = cli_dumpscan(fd, 0, filesize, ctx);
if(ret == CL_VIRUS)
return ret;
}
lseek(fd, pos + filesize, SEEK_SET);
}
return CL_CLEAN;
}
int cli_scancpio_newc(int fd, cli_ctx *ctx, int crc)
{
struct cpio_hdr_newc hdr_newc;
char name[513], buff[9];
unsigned int file = 0, trailer = 0;
uint32_t filesize, namesize, hdr_namesize, pad;
int ret;
off_t pos;
while(read(fd, &hdr_newc, sizeof(hdr_newc)) == sizeof(hdr_newc)) {
if(!hdr_newc.magic[0] && trailer)
return CL_SUCCESS;
if((!crc && strncmp(hdr_newc.magic, "070701", 6)) || (crc && strncmp(hdr_newc.magic, "070702", 6))) {
cli_dbgmsg("cli_scancpio_newc: Invalid magic string\n");
return CL_EFORMAT;
}
cli_dbgmsg("CPIO: -- File %u --\n", ++file);
strncpy(buff, hdr_newc.namesize, 8);
buff[8] = 0;
if(sscanf(buff, "%x", &hdr_namesize) != 1) {
cli_dbgmsg("cli_scancpio_newc: Can't convert name size\n");
return CL_EFORMAT;
}
if(hdr_namesize) {
namesize = MIN(sizeof(name), hdr_namesize);
if(read(fd, name, namesize) != namesize) {
cli_dbgmsg("cli_scancpio_newc: Can't read file name\n");
return CL_EFORMAT;
}
name[namesize - 1] = 0;
sanitname(name);
cli_dbgmsg("CPIO: Name: %s\n", name);
if(!strcmp(name, "TRAILER!!!"))
trailer = 1;
pad = (4 - (sizeof(hdr_newc) + hdr_namesize) % 4) % 4;
if(namesize < hdr_namesize) {
if(pad)
hdr_namesize += pad;
lseek(fd, hdr_namesize - namesize, SEEK_CUR);
} else if(pad)
lseek(fd, pad, SEEK_CUR);
}
strncpy(buff, hdr_newc.filesize, 8);
buff[8] = 0;
if(sscanf(buff, "%x", &filesize) != 1) {
cli_dbgmsg("cli_scancpio_newc: Can't convert file size\n");
return CL_EFORMAT;
}
cli_dbgmsg("CPIO: Filesize: %u\n", filesize);
if(!filesize)
continue;
pos = lseek(fd, 0, SEEK_CUR);
ret = cli_checklimits("cli_scancpio_newc", ctx, filesize, 0, 0);
if(ret == CL_EMAXFILES) {
return ret;
} else if(ret == CL_SUCCESS) {
ret = cli_dumpscan(fd, 0, filesize, ctx);
if(ret == CL_VIRUS)
return ret;
}
if((pad = filesize % 4))
filesize += (4 - pad);
lseek(fd, pos + filesize, SEEK_SET);
}
return CL_CLEAN;
}