369 lines
8.6 KiB
C
369 lines
8.6 KiB
C
/*
|
|
* Copyright (c) Christos Zoulas 2003.
|
|
* All Rights Reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice immediately at the beginning of the file, without modification,
|
|
* this list of conditions, and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
|
|
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
#include "file.h"
|
|
#include "magic.h"
|
|
#include <stdarg.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <ctype.h>
|
|
#if defined(HAVE_WCHAR_H)
|
|
#include <wchar.h>
|
|
#endif
|
|
#if defined(HAVE_WCTYPE_H)
|
|
#include <wctype.h>
|
|
#endif
|
|
#if defined(HAVE_LIMITS_H)
|
|
#include <limits.h>
|
|
#endif
|
|
#ifndef SIZE_T_MAX
|
|
#ifdef __LP64__
|
|
#define SIZE_T_MAX (size_t)0xfffffffffffffffffU
|
|
#else
|
|
#define SIZE_T_MAX (size_t)0xffffffffU
|
|
#endif
|
|
#endif
|
|
|
|
#ifndef lint
|
|
FILE_RCSID("@(#)$File: funcs.c,v 1.32 2007/05/24 17:22:27 christos Exp $")
|
|
#endif /* lint */
|
|
|
|
#ifndef HAVE_VSNPRINTF
|
|
int vsnprintf(char *, size_t, const char *, va_list);
|
|
#endif
|
|
|
|
/*
|
|
* Like printf, only we print to a buffer and advance it.
|
|
*/
|
|
protected int
|
|
file_printf(struct magic_set *ms, const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
size_t len, size;
|
|
char *buf;
|
|
|
|
va_start(ap, fmt);
|
|
|
|
if ((len = vsnprintf(ms->o.ptr, ms->o.left, fmt, ap)) >= ms->o.left) {
|
|
long diff; /* XXX: really ptrdiff_t */
|
|
|
|
va_end(ap);
|
|
size = (ms->o.size - ms->o.left) + len + 1024;
|
|
if ((buf = realloc(ms->o.buf, size)) == NULL) {
|
|
file_oomem(ms, size);
|
|
return -1;
|
|
}
|
|
diff = ms->o.ptr - ms->o.buf;
|
|
ms->o.ptr = buf + diff;
|
|
ms->o.buf = buf;
|
|
ms->o.left = size - diff;
|
|
ms->o.size = size;
|
|
|
|
va_start(ap, fmt);
|
|
len = vsnprintf(ms->o.ptr, ms->o.left, fmt, ap);
|
|
}
|
|
va_end(ap);
|
|
ms->o.ptr += len;
|
|
ms->o.left -= len;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* error - print best error message possible
|
|
*/
|
|
/*VARARGS*/
|
|
private void
|
|
file_error_core(struct magic_set *ms, int error, const char *f, va_list va,
|
|
uint32_t lineno)
|
|
{
|
|
size_t len;
|
|
/* Only the first error is ok */
|
|
if (ms->haderr)
|
|
return;
|
|
len = 0;
|
|
if (lineno != 0) {
|
|
(void)snprintf(ms->o.buf, ms->o.size, "line %u: ", lineno);
|
|
len = strlen(ms->o.buf);
|
|
}
|
|
(void)vsnprintf(ms->o.buf + len, ms->o.size - len, f, va);
|
|
if (error > 0) {
|
|
len = strlen(ms->o.buf);
|
|
(void)snprintf(ms->o.buf + len, ms->o.size - len, " (%s)",
|
|
strerror(error));
|
|
}
|
|
ms->haderr++;
|
|
ms->error = error;
|
|
}
|
|
|
|
/*VARARGS*/
|
|
protected void
|
|
file_error(struct magic_set *ms, int error, const char *f, ...)
|
|
{
|
|
va_list va;
|
|
va_start(va, f);
|
|
file_error_core(ms, error, f, va, 0);
|
|
va_end(va);
|
|
}
|
|
|
|
/*
|
|
* Print an error with magic line number.
|
|
*/
|
|
/*VARARGS*/
|
|
protected void
|
|
file_magerror(struct magic_set *ms, const char *f, ...)
|
|
{
|
|
va_list va;
|
|
va_start(va, f);
|
|
file_error_core(ms, 0, f, va, ms->line);
|
|
va_end(va);
|
|
}
|
|
|
|
protected void
|
|
file_oomem(struct magic_set *ms, size_t len)
|
|
{
|
|
file_error(ms, errno, "cannot allocate %zu bytes", len);
|
|
}
|
|
|
|
protected void
|
|
file_badseek(struct magic_set *ms)
|
|
{
|
|
file_error(ms, errno, "error seeking");
|
|
}
|
|
|
|
protected void
|
|
file_badread(struct magic_set *ms)
|
|
{
|
|
file_error(ms, errno, "error reading");
|
|
}
|
|
|
|
#ifndef COMPILE_ONLY
|
|
protected int
|
|
file_buffer(struct magic_set *ms, int fd, const char *inname, const void *buf,
|
|
size_t nb)
|
|
{
|
|
int m;
|
|
|
|
#ifdef __EMX__
|
|
if ((ms->flags & MAGIC_NO_CHECK_APPTYPE) == 0 && inname) {
|
|
switch (file_os2_apptype(ms, inname, buf, nb)) {
|
|
case -1:
|
|
return -1;
|
|
case 0:
|
|
break;
|
|
default:
|
|
return 1;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* try compression stuff */
|
|
if ((ms->flags & MAGIC_NO_CHECK_COMPRESS) != 0 ||
|
|
(m = file_zmagic(ms, fd, inname, buf, nb)) == 0) {
|
|
/* Check if we have a tar file */
|
|
if ((ms->flags & MAGIC_NO_CHECK_TAR) != 0 ||
|
|
(m = file_is_tar(ms, buf, nb)) == 0) {
|
|
/* try tests in /etc/magic (or surrogate magic file) */
|
|
if ((ms->flags & MAGIC_NO_CHECK_SOFT) != 0 ||
|
|
(m = file_softmagic(ms, buf, nb)) == 0) {
|
|
/* try known keywords, check whether it is ASCII */
|
|
if ((ms->flags & MAGIC_NO_CHECK_ASCII) != 0 ||
|
|
(m = file_ascmagic(ms, buf, nb)) == 0) {
|
|
/* abandon hope, all ye who remain here */
|
|
if (file_printf(ms, ms->flags & MAGIC_MIME ?
|
|
(nb ? "application/octet-stream" :
|
|
"application/empty") :
|
|
(nb ? "data" :
|
|
"empty")) == -1)
|
|
return -1;
|
|
m = 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
#ifdef BUILTIN_ELF
|
|
if ((ms->flags & MAGIC_NO_CHECK_ELF) == 0 && m == 1 && nb > 5 && fd != -1) {
|
|
/*
|
|
* We matched something in the file, so this *might*
|
|
* be an ELF file, and the file is at least 5 bytes
|
|
* long, so if it's an ELF file it has at least one
|
|
* byte past the ELF magic number - try extracting
|
|
* information from the ELF headers that cannot easily
|
|
* be extracted with rules in the magic file.
|
|
*/
|
|
(void)file_tryelf(ms, fd, buf, nb);
|
|
}
|
|
#endif
|
|
return m;
|
|
}
|
|
#endif
|
|
|
|
protected int
|
|
file_reset(struct magic_set *ms)
|
|
{
|
|
if (ms->mlist == NULL) {
|
|
file_error(ms, 0, "no magic files loaded");
|
|
return -1;
|
|
}
|
|
ms->o.ptr = ms->o.buf;
|
|
ms->o.left = ms->o.size;
|
|
ms->haderr = 0;
|
|
ms->error = -1;
|
|
return 0;
|
|
}
|
|
|
|
#define OCTALIFY(n, o) \
|
|
/*LINTED*/ \
|
|
(void)(*(n)++ = '\\', \
|
|
*(n)++ = (((uint32_t)*(o) >> 6) & 3) + '0', \
|
|
*(n)++ = (((uint32_t)*(o) >> 3) & 7) + '0', \
|
|
*(n)++ = (((uint32_t)*(o) >> 0) & 7) + '0', \
|
|
(o)++)
|
|
|
|
protected const char *
|
|
file_getbuffer(struct magic_set *ms)
|
|
{
|
|
char *pbuf, *op, *np;
|
|
size_t psize, len;
|
|
|
|
if (ms->haderr)
|
|
return NULL;
|
|
|
|
if (ms->flags & MAGIC_RAW)
|
|
return ms->o.buf;
|
|
|
|
len = ms->o.size - ms->o.left;
|
|
/* * 4 is for octal representation, + 1 is for NUL */
|
|
if (len > (SIZE_T_MAX - 1) / 4) {
|
|
file_oomem(ms, len);
|
|
return NULL;
|
|
}
|
|
psize = len * 4 + 1;
|
|
if (ms->o.psize < psize) {
|
|
if ((pbuf = realloc(ms->o.pbuf, psize)) == NULL) {
|
|
file_oomem(ms, psize);
|
|
return NULL;
|
|
}
|
|
ms->o.psize = psize;
|
|
ms->o.pbuf = pbuf;
|
|
}
|
|
|
|
#if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH)
|
|
{
|
|
mbstate_t state;
|
|
wchar_t nextchar;
|
|
int mb_conv = 1;
|
|
size_t bytesconsumed;
|
|
char *eop;
|
|
(void)memset(&state, 0, sizeof(mbstate_t));
|
|
|
|
np = ms->o.pbuf;
|
|
op = ms->o.buf;
|
|
eop = op + strlen(ms->o.buf);
|
|
|
|
while (op < eop) {
|
|
bytesconsumed = mbrtowc(&nextchar, op,
|
|
(size_t)(eop - op), &state);
|
|
if (bytesconsumed == (size_t)(-1) ||
|
|
bytesconsumed == (size_t)(-2)) {
|
|
mb_conv = 0;
|
|
break;
|
|
}
|
|
|
|
if (iswprint(nextchar)) {
|
|
(void)memcpy(np, op, bytesconsumed);
|
|
op += bytesconsumed;
|
|
np += bytesconsumed;
|
|
} else {
|
|
while (bytesconsumed-- > 0)
|
|
OCTALIFY(np, op);
|
|
}
|
|
}
|
|
*np = '\0';
|
|
|
|
/* Parsing succeeded as a multi-byte sequence */
|
|
if (mb_conv != 0)
|
|
return ms->o.pbuf;
|
|
}
|
|
#endif
|
|
|
|
for (np = ms->o.pbuf, op = ms->o.buf; *op; op++) {
|
|
if (isprint((unsigned char)*op)) {
|
|
*np++ = *op;
|
|
} else {
|
|
OCTALIFY(np, op);
|
|
}
|
|
}
|
|
*np = '\0';
|
|
return ms->o.pbuf;
|
|
}
|
|
|
|
protected int
|
|
file_check_mem(struct magic_set *ms, unsigned int level)
|
|
{
|
|
size_t len;
|
|
|
|
if (level >= ms->c.len) {
|
|
len = (ms->c.len += 20) * sizeof(*ms->c.li);
|
|
ms->c.li = (ms->c.li == NULL) ? malloc(len) :
|
|
realloc(ms->c.li, len);
|
|
if (ms->c.li == NULL) {
|
|
file_oomem(ms, len);
|
|
return -1;
|
|
}
|
|
}
|
|
ms->c.li[level].got_match = 0;
|
|
#ifdef ENABLE_CONDITIONALS
|
|
ms->c.li[level].last_match = 0;
|
|
ms->c.li[level].last_cond = COND_NONE;
|
|
#endif /* ENABLE_CONDITIONALS */
|
|
return 0;
|
|
}
|
|
/*
|
|
* Yes these wrappers suffer from buffer overflows, but if your OS does not
|
|
* have the real functions, maybe you should consider replacing your OS?
|
|
*/
|
|
#ifndef HAVE_VSNPRINTF
|
|
int
|
|
vsnprintf(char *buf, size_t len, const char *fmt, va_list ap)
|
|
{
|
|
return vsprintf(buf, fmt, ap);
|
|
}
|
|
#endif
|
|
|
|
#ifndef HAVE_SNPRINTF
|
|
/*ARGSUSED*/
|
|
int
|
|
snprintf(char *buf, size_t len, const char *fmt, ...)
|
|
{
|
|
int rv;
|
|
va_list ap;
|
|
va_start(ap, fmt);
|
|
rv = vsprintf(buf, fmt, ap);
|
|
va_end(ap);
|
|
return rv;
|
|
}
|
|
#endif
|