2 * Copyright (c) Christos Zoulas 2003.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice immediately at the beginning of the file, without modification,
10 * this list of conditions, and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
19 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 #if defined(HAVE_WCHAR_H)
36 #if defined(HAVE_WCTYPE_H)
39 #if defined(HAVE_LIMITS_H)
44 #define SIZE_T_MAX (size_t)0xffffffffffffffffU
46 #define SIZE_T_MAX (size_t)0xffffffffU
51 FILE_RCSID("@(#)$File: funcs.c,v 1.35 2007/12/27 16:35:59 christos Exp $")
54 #ifndef HAVE_VSNPRINTF
55 int vsnprintf(char *, size_t, const char *, va_list);
59 * Like printf, only we print to a buffer and advance it.
62 file_printf(struct magic_set *ms, const char *fmt, ...)
71 len = vsnprintf(ms->o.ptr, ms->o.left, fmt, ap);
74 if (len >= (ssize_t)ms->o.left) {
75 long diff; /* XXX: really ptrdiff_t */
78 size = (ms->o.size - ms->o.left) + len + 1024;
79 if ((buf = realloc(ms->o.buf, size)) == NULL) {
83 diff = ms->o.ptr - ms->o.buf;
84 ms->o.ptr = buf + diff;
86 ms->o.left = size - diff;
90 len = vsnprintf(ms->o.ptr, ms->o.left, fmt, ap);
99 file_error(ms, errno, "vsnprintf failed");
104 * error - print best error message possible
108 file_error_core(struct magic_set *ms, int error, const char *f, va_list va,
112 /* Only the first error is ok */
117 (void)snprintf(ms->o.buf, ms->o.size, "line %u: ", lineno);
118 len = strlen(ms->o.buf);
120 (void)vsnprintf(ms->o.buf + len, ms->o.size - len, f, va);
122 len = strlen(ms->o.buf);
123 (void)snprintf(ms->o.buf + len, ms->o.size - len, " (%s)",
132 file_error(struct magic_set *ms, int error, const char *f, ...)
136 file_error_core(ms, error, f, va, 0);
141 * Print an error with magic line number.
145 file_magerror(struct magic_set *ms, const char *f, ...)
149 file_error_core(ms, 0, f, va, ms->line);
154 file_oomem(struct magic_set *ms, size_t len)
156 file_error(ms, errno, "cannot allocate %zu bytes", len);
160 file_badseek(struct magic_set *ms)
162 file_error(ms, errno, "error seeking");
166 file_badread(struct magic_set *ms)
168 file_error(ms, errno, "error reading");
173 file_buffer(struct magic_set *ms, int fd, const char *inname, const void *buf,
177 int mime = ms->flags & MAGIC_MIME;
180 if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
181 file_printf(ms, mime ? "application/x-empty" :
185 } else if (nb == 1) {
186 if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
187 file_printf(ms, mime ? "application/octet-stream" :
188 "very short file (no magic)") == -1)
194 if ((ms->flags & MAGIC_NO_CHECK_APPTYPE) == 0 && inname) {
195 switch (file_os2_apptype(ms, inname, buf, nb)) {
206 /* try compression stuff */
207 if ((ms->flags & MAGIC_NO_CHECK_COMPRESS) != 0 ||
208 (m = file_zmagic(ms, fd, inname, buf, nb)) == 0) {
209 /* Check if we have a tar file */
210 if ((ms->flags & MAGIC_NO_CHECK_TAR) != 0 ||
211 (m = file_is_tar(ms, buf, nb)) == 0) {
212 /* try tests in /etc/magic (or surrogate magic file) */
213 if ((ms->flags & MAGIC_NO_CHECK_SOFT) != 0 ||
214 (m = file_softmagic(ms, buf, nb)) == 0) {
215 /* try known keywords, check whether it is ASCII */
216 if ((ms->flags & MAGIC_NO_CHECK_ASCII) != 0 ||
217 (m = file_ascmagic(ms, buf, nb)) == 0) {
218 /* abandon hope, all ye who remain here */
219 if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
220 file_printf(ms, mime ? "application/octet-stream" :
229 if ((ms->flags & MAGIC_NO_CHECK_ELF) == 0 && m == 1 &&
230 nb > 5 && fd != -1) {
232 * We matched something in the file, so this *might*
233 * be an ELF file, and the file is at least 5 bytes
234 * long, so if it's an ELF file it has at least one
235 * byte past the ELF magic number - try extracting
236 * information from the ELF headers that cannot easily
237 * be extracted with rules in the magic file.
239 (void)file_tryelf(ms, fd, buf, nb);
247 file_reset(struct magic_set *ms)
249 if (ms->mlist == NULL) {
250 file_error(ms, 0, "no magic files loaded");
253 ms->o.ptr = ms->o.buf;
254 ms->o.left = ms->o.size;
260 #define OCTALIFY(n, o) \
262 (void)(*(n)++ = '\\', \
263 *(n)++ = (((uint32_t)*(o) >> 6) & 3) + '0', \
264 *(n)++ = (((uint32_t)*(o) >> 3) & 7) + '0', \
265 *(n)++ = (((uint32_t)*(o) >> 0) & 7) + '0', \
268 protected const char *
269 file_getbuffer(struct magic_set *ms)
271 char *pbuf, *op, *np;
277 if (ms->flags & MAGIC_RAW)
280 len = ms->o.size - ms->o.left;
281 /* * 4 is for octal representation, + 1 is for NUL */
282 if (len > (SIZE_T_MAX - 1) / 4) {
287 if (ms->o.psize < psize) {
288 if ((pbuf = realloc(ms->o.pbuf, psize)) == NULL) {
289 file_oomem(ms, psize);
296 #if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH)
301 size_t bytesconsumed;
303 (void)memset(&state, 0, sizeof(mbstate_t));
307 eop = op + strlen(ms->o.buf);
310 bytesconsumed = mbrtowc(&nextchar, op,
311 (size_t)(eop - op), &state);
312 if (bytesconsumed == (size_t)(-1) ||
313 bytesconsumed == (size_t)(-2)) {
318 if (iswprint(nextchar)) {
319 (void)memcpy(np, op, bytesconsumed);
323 while (bytesconsumed-- > 0)
329 /* Parsing succeeded as a multi-byte sequence */
335 for (np = ms->o.pbuf, op = ms->o.buf; *op; op++) {
336 if (isprint((unsigned char)*op)) {
347 file_check_mem(struct magic_set *ms, unsigned int level)
351 if (level >= ms->c.len) {
352 len = (ms->c.len += 20) * sizeof(*ms->c.li);
353 ms->c.li = (ms->c.li == NULL) ? malloc(len) :
354 realloc(ms->c.li, len);
355 if (ms->c.li == NULL) {
360 ms->c.li[level].got_match = 0;
361 #ifdef ENABLE_CONDITIONALS
362 ms->c.li[level].last_match = 0;
363 ms->c.li[level].last_cond = COND_NONE;
364 #endif /* ENABLE_CONDITIONALS */
368 * Yes these wrappers suffer from buffer overflows, but if your OS does not
369 * have the real functions, maybe you should consider replacing your OS?
371 #ifndef HAVE_VSNPRINTF
373 vsnprintf(char *buf, size_t len, const char *fmt, va_list ap)
375 return vsprintf(buf, fmt, ap);
379 #ifndef HAVE_SNPRINTF
382 snprintf(char *buf, size_t len, const char *fmt, ...)
387 rv = vsprintf(buf, fmt, ap);