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
30 FILE_RCSID("@(#)$File: funcs.c,v 1.115 2020/02/20 15:50:20 christos Exp $")
39 #if defined(HAVE_WCHAR_H)
42 #if defined(HAVE_WCTYPE_H)
48 #define SIZE_MAX ((size_t)~0)
52 file_copystr(char *buf, size_t blen, size_t width, const char *str)
56 strlcpy(buf, str, width);
61 file_clearbuf(struct magic_set *ms)
69 file_checkfield(char *msg, size_t mlen, const char *what, const char **pp)
74 while (*p && isdigit((unsigned char)*p))
75 fw = fw * 10 + (*p++ - '0');
82 snprintf(msg, mlen, "field %s too large: %d", what, fw);
88 file_checkfmt(char *msg, size_t mlen, const char *fmt)
90 for (const char *p = fmt; *p; p++) {
95 // Skip uninteresting.
96 while (strchr("0.'+- ", *p) != NULL)
100 snprintf(msg, mlen, "* not allowed in format");
104 if (!file_checkfield(msg, mlen, "width", &p))
109 if (!file_checkfield(msg, mlen, "precision", &p))
113 if (!isalpha((unsigned char)*p)) {
115 snprintf(msg, mlen, "bad format char: %c", *p);
123 * Like printf, only we append to a buffer.
126 file_vprintf(struct magic_set *ms, const char *fmt, va_list ap)
132 if (ms->event_flags & EVENT_HAD_ERR)
135 if (file_checkfmt(tbuf, sizeof(tbuf), fmt)) {
137 file_error(ms, 0, "Bad magic format `%s' (%s)", fmt, tbuf);
141 len = vasprintf(&buf, fmt, ap);
142 if (len < 0 || (size_t)len > 1024 || len + ms->o.blen > 1024 * 1024) {
143 size_t blen = ms->o.blen;
146 file_error(ms, 0, "Output buffer space exceeded %d+%zu", len,
151 if (ms->o.buf != NULL) {
152 len = asprintf(&newstr, "%s%s", ms->o.buf, buf);
164 file_error(ms, errno, "vasprintf failed");
169 file_printf(struct magic_set *ms, const char *fmt, ...)
175 rv = file_vprintf(ms, fmt, ap);
181 * error - print best error message possible
184 __attribute__((__format__(__printf__, 3, 0)))
186 file_error_core(struct magic_set *ms, int error, const char *f, va_list va,
189 /* Only the first error is ok */
190 if (ms->event_flags & EVENT_HAD_ERR)
194 (void)file_printf(ms, "line %" SIZE_T_FORMAT "u:", lineno);
196 if (ms->o.buf && *ms->o.buf)
197 (void)file_printf(ms, " ");
198 (void)file_vprintf(ms, f, va);
200 (void)file_printf(ms, " (%s)", strerror(error));
201 ms->event_flags |= EVENT_HAD_ERR;
207 file_error(struct magic_set *ms, int error, const char *f, ...)
211 file_error_core(ms, error, f, va, 0);
216 * Print an error with magic line number.
220 file_magerror(struct magic_set *ms, const char *f, ...)
224 file_error_core(ms, 0, f, va, ms->line);
229 file_oomem(struct magic_set *ms, size_t len)
231 file_error(ms, errno, "cannot allocate %" SIZE_T_FORMAT "u bytes",
236 file_badseek(struct magic_set *ms)
238 file_error(ms, errno, "error seeking");
242 file_badread(struct magic_set *ms)
244 file_error(ms, errno, "error reading");
250 file_separator(struct magic_set *ms)
252 return file_printf(ms, "\n- ");
256 checkdone(struct magic_set *ms, int *rv)
258 if ((ms->flags & MAGIC_CONTINUE) == 0)
260 if (file_separator(ms) == -1)
266 file_default(struct magic_set *ms, size_t nb)
268 if (ms->flags & MAGIC_MIME) {
269 if ((ms->flags & MAGIC_MIME_TYPE) &&
270 file_printf(ms, "application/%s",
271 nb ? "octet-stream" : "x-empty") == -1)
275 if (ms->flags & MAGIC_APPLE) {
276 if (file_printf(ms, "UNKNUNKN") == -1)
280 if (ms->flags & MAGIC_EXTENSION) {
281 if (file_printf(ms, "???") == -1)
289 * The magic detection functions return:
296 file_buffer(struct magic_set *ms, int fd, struct stat *st,
297 const char *inname __attribute__ ((__unused__)),
298 const void *buf, size_t nb)
300 int m = 0, rv = 0, looks_text = 0;
301 const char *code = NULL;
302 const char *code_mime = "binary";
303 const char *def = "data";
304 const char *ftype = NULL;
308 buffer_init(&b, fd, st, buf, nb);
309 ms->mode = b.st.st_mode;
314 } else if (nb == 1) {
315 def = "very short file (no magic)";
319 if ((ms->flags & MAGIC_NO_CHECK_ENCODING) == 0) {
320 looks_text = file_encoding(ms, &b, NULL, 0,
321 &code, &code_mime, &ftype);
325 if ((ms->flags & MAGIC_NO_CHECK_APPTYPE) == 0 && inname) {
326 m = file_os2_apptype(ms, inname, &b);
327 if ((ms->flags & MAGIC_DEBUG) != 0)
328 (void)fprintf(stderr, "[try os2_apptype %d]\n", m);
340 /* try compression stuff */
341 if ((ms->flags & MAGIC_NO_CHECK_COMPRESS) == 0) {
342 m = file_zmagic(ms, &b, inname);
343 if ((ms->flags & MAGIC_DEBUG) != 0)
344 (void)fprintf(stderr, "[try zmagic %d]\n", m);
350 /* Check if we have a tar file */
351 if ((ms->flags & MAGIC_NO_CHECK_TAR) == 0) {
352 m = file_is_tar(ms, &b);
353 if ((ms->flags & MAGIC_DEBUG) != 0)
354 (void)fprintf(stderr, "[try tar %d]\n", m);
356 if (checkdone(ms, &rv))
361 /* Check if we have a JSON file */
362 if ((ms->flags & MAGIC_NO_CHECK_JSON) == 0) {
363 m = file_is_json(ms, &b);
364 if ((ms->flags & MAGIC_DEBUG) != 0)
365 (void)fprintf(stderr, "[try json %d]\n", m);
367 if (checkdone(ms, &rv))
372 /* Check if we have a CSV file */
373 if ((ms->flags & MAGIC_NO_CHECK_CSV) == 0) {
374 m = file_is_csv(ms, &b, looks_text);
375 if ((ms->flags & MAGIC_DEBUG) != 0)
376 (void)fprintf(stderr, "[try csv %d]\n", m);
378 if (checkdone(ms, &rv))
383 /* Check if we have a CDF file */
384 if ((ms->flags & MAGIC_NO_CHECK_CDF) == 0) {
385 m = file_trycdf(ms, &b);
386 if ((ms->flags & MAGIC_DEBUG) != 0)
387 (void)fprintf(stderr, "[try cdf %d]\n", m);
389 if (checkdone(ms, &rv))
394 if ((ms->flags & MAGIC_NO_CHECK_ELF) == 0 && nb > 5 && fd != -1) {
397 * We matched something in the file, so this
398 * *might* be an ELF file, and the file is at
399 * least 5 bytes long, so if it's an ELF file
400 * it has at least one byte past the ELF magic
401 * number - try extracting information from the
402 * ELF headers that cannot easily be extracted
403 * with rules in the magic file. We we don't
404 * print the information yet.
406 if ((pb = file_push_buffer(ms)) == NULL)
409 rv = file_tryelf(ms, &b);
410 rbuf = file_pop_buffer(ms, pb);
415 if ((ms->flags & MAGIC_DEBUG) != 0)
416 (void)fprintf(stderr, "[try elf %d]\n", m);
420 /* try soft magic tests */
421 if ((ms->flags & MAGIC_NO_CHECK_SOFT) == 0) {
422 m = file_softmagic(ms, &b, NULL, NULL, BINTEST, looks_text);
423 if ((ms->flags & MAGIC_DEBUG) != 0)
424 (void)fprintf(stderr, "[try softmagic %d]\n", m);
425 if (m == 1 && rbuf) {
426 if (file_printf(ms, "%s", rbuf) == -1)
430 if (checkdone(ms, &rv))
435 /* try text properties */
436 if ((ms->flags & MAGIC_NO_CHECK_TEXT) == 0) {
438 m = file_ascmagic(ms, &b, looks_text);
439 if ((ms->flags & MAGIC_DEBUG) != 0)
440 (void)fprintf(stderr, "[try ascmagic %d]\n", m);
450 rv = file_default(ms, nb);
452 if (file_printf(ms, "%s", def) == -1)
456 if ((ms->flags & MAGIC_MIME_ENCODING) != 0) {
457 if (ms->flags & MAGIC_MIME_TYPE)
458 if (file_printf(ms, "; charset=") == -1)
460 if (file_printf(ms, "%s", code_mime) == -1)
476 file_reset(struct magic_set *ms, int checkloaded)
478 if (checkloaded && ms->mlist[0] == NULL) {
479 file_error(ms, 0, "no magic files loaded");
487 ms->event_flags &= ~EVENT_HAD_ERR;
492 #define OCTALIFY(n, o) \
494 (void)(*(n)++ = '\\', \
495 *(n)++ = ((CAST(uint32_t, *(o)) >> 6) & 3) + '0', \
496 *(n)++ = ((CAST(uint32_t, *(o)) >> 3) & 7) + '0', \
497 *(n)++ = ((CAST(uint32_t, *(o)) >> 0) & 7) + '0', \
500 protected const char *
501 file_getbuffer(struct magic_set *ms)
503 char *pbuf, *op, *np;
506 if (ms->event_flags & EVENT_HAD_ERR)
509 if (ms->flags & MAGIC_RAW)
512 if (ms->o.buf == NULL)
515 /* * 4 is for octal representation, + 1 is for NUL */
516 len = strlen(ms->o.buf);
517 if (len > (SIZE_MAX - 1) / 4) {
522 if ((pbuf = CAST(char *, realloc(ms->o.pbuf, psize))) == NULL) {
523 file_oomem(ms, psize);
528 #if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH)
533 size_t bytesconsumed;
535 (void)memset(&state, 0, sizeof(mbstate_t));
542 bytesconsumed = mbrtowc(&nextchar, op,
543 CAST(size_t, eop - op), &state);
544 if (bytesconsumed == CAST(size_t, -1) ||
545 bytesconsumed == CAST(size_t, -2)) {
550 if (iswprint(nextchar)) {
551 (void)memcpy(np, op, bytesconsumed);
555 while (bytesconsumed-- > 0)
561 /* Parsing succeeded as a multi-byte sequence */
567 for (np = ms->o.pbuf, op = ms->o.buf; *op;) {
568 if (isprint(CAST(unsigned char, *op))) {
579 file_check_mem(struct magic_set *ms, unsigned int level)
583 if (level >= ms->c.len) {
584 len = (ms->c.len = 20 + level) * sizeof(*ms->c.li);
585 ms->c.li = CAST(struct level_info *, (ms->c.li == NULL) ?
587 realloc(ms->c.li, len));
588 if (ms->c.li == NULL) {
593 ms->c.li[level].got_match = 0;
594 #ifdef ENABLE_CONDITIONALS
595 ms->c.li[level].last_match = 0;
596 ms->c.li[level].last_cond = COND_NONE;
597 #endif /* ENABLE_CONDITIONALS */
602 file_printedlen(const struct magic_set *ms)
608 file_replace(struct magic_set *ms, const char *pat, const char *rep)
613 rc = file_regcomp(&rx, pat, REG_EXTENDED);
615 file_regerror(&rx, rc, ms);
619 while (file_regexec(&rx, ms->o.buf, 1, &rm, 0) == 0) {
620 ms->o.buf[rm.rm_so] = '\0';
621 if (file_printf(ms, "%s%s", rep,
622 rm.rm_eo != 0 ? ms->o.buf + rm.rm_eo : "") == -1)
634 file_regcomp(file_regex_t *rx, const char *pat, int flags)
637 rx->c_lc_ctype = newlocale(LC_CTYPE_MASK, "C", 0);
638 assert(rx->c_lc_ctype != NULL);
639 rx->old_lc_ctype = uselocale(rx->c_lc_ctype);
640 assert(rx->old_lc_ctype != NULL);
642 rx->old_lc_ctype = setlocale(LC_CTYPE, NULL);
643 assert(rx->old_lc_ctype != NULL);
644 rx->old_lc_ctype = strdup(rx->old_lc_ctype);
645 assert(rx->old_lc_ctype != NULL);
646 (void)setlocale(LC_CTYPE, "C");
650 return rx->rc = regcomp(&rx->rx, pat, flags);
654 file_regexec(file_regex_t *rx, const char *str, size_t nmatch,
655 regmatch_t* pmatch, int eflags)
658 /* XXX: force initialization because glibc does not always do this */
660 memset(pmatch, 0, nmatch * sizeof(*pmatch));
661 return regexec(&rx->rx, str, nmatch, pmatch, eflags);
665 file_regfree(file_regex_t *rx)
670 (void)uselocale(rx->old_lc_ctype);
671 freelocale(rx->c_lc_ctype);
673 (void)setlocale(LC_CTYPE, rx->old_lc_ctype);
674 free(rx->old_lc_ctype);
679 file_regerror(file_regex_t *rx, int rc, struct magic_set *ms)
683 (void)regerror(rc, &rx->rx, errmsg, sizeof(errmsg));
684 file_magerror(ms, "regex error %d for `%s', (%s)", rc, rx->pat,
688 protected file_pushbuf_t *
689 file_push_buffer(struct magic_set *ms)
693 if (ms->event_flags & EVENT_HAD_ERR)
696 if ((pb = (CAST(file_pushbuf_t *, malloc(sizeof(*pb))))) == NULL)
700 pb->blen = ms->o.blen;
701 pb->offset = ms->offset;
711 file_pop_buffer(struct magic_set *ms, file_pushbuf_t *pb)
715 if (ms->event_flags & EVENT_HAD_ERR) {
724 ms->o.blen = pb->blen;
725 ms->offset = pb->offset;
732 * convert string to ascii printable format.
735 file_printable(char *buf, size_t bufsiz, const char *str, size_t slen)
737 char *ptr, *eptr = buf + bufsiz - 1;
738 const unsigned char *s = RCAST(const unsigned char *, str);
739 const unsigned char *es = s + slen;
741 for (ptr = buf; ptr < eptr && s < es && *s; s++) {
749 *ptr++ = ((CAST(unsigned int, *s) >> 6) & 7) + '0';
750 *ptr++ = ((CAST(unsigned int, *s) >> 3) & 7) + '0';
751 *ptr++ = ((CAST(unsigned int, *s) >> 0) & 7) + '0';
765 file_parse_guid(const char *s, uint64_t *guid)
767 struct guid *g = CAST(struct guid *, guid);
769 "%8x-%4hx-%4hx-%2hhx%2hhx-%2hhx%2hhx%2hhx%2hhx%2hhx%2hhx",
770 &g->data1, &g->data2, &g->data3, &g->data4[0], &g->data4[1],
771 &g->data4[2], &g->data4[3], &g->data4[4], &g->data4[5],
772 &g->data4[6], &g->data4[7]) == 11 ? 0 : -1;
776 file_print_guid(char *str, size_t len, const uint64_t *guid)
778 const struct guid *g = CAST(const struct guid *, guid);
780 return snprintf(str, len, "%.8X-%.4hX-%.4hX-%.2hhX%.2hhX-"
781 "%.2hhX%.2hhX%.2hhX%.2hhX%.2hhX%.2hhX",
782 g->data1, g->data2, g->data3, g->data4[0], g->data4[1],
783 g->data4[2], g->data4[3], g->data4[4], g->data4[5],
784 g->data4[6], g->data4[7]);