external/bsd/file/dist/src/funcs.c

   1 /*      $NetBSD: funcs.c,v 1.1.1.1 2009/05/08 16:35:06 christos Exp $   */
   2
   3 /*
   4  * Copyright (c) Christos Zoulas 2003.
   5  * All Rights Reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice immediately at the beginning of the file, without modification,
  12  *    this list of conditions, and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29 #include "file.h"
  30
  31 #ifndef lint
  32 #if 0
  33 FILE_RCSID("@(#)$File: funcs.c,v 1.53 2009/04/07 11:07:00 christos Exp $")
  34 #else
  35 __RCSID("$NetBSD: funcs.c,v 1.1.1.1 2009/05/08 16:35:06 christos Exp $");
  36 #endif
  37 #endif  /* lint */
  38
  39 #include "magic.h"
  40 #include <stdarg.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <ctype.h>
  44 #if defined(HAVE_WCHAR_H)
  45 #include <wchar.h>
  46 #endif
  47 #if defined(HAVE_WCTYPE_H)
  48 #include <wctype.h>
  49 #endif
  50 #if defined(HAVE_LIMITS_H)
  51 #include <limits.h>
  52 #endif
  53
  54 #ifndef SIZE_MAX
  55 #define SIZE_MAX        ((size_t)~0)
  56 #endif
  57
  58 /*
  59  * Like printf, only we append to a buffer.
  60  */
  61 protected int
  62 file_vprintf(struct magic_set *ms, const char *fmt, va_list ap)
  63 {
  64         int len;
  65         char *buf, *newstr;
  66
  67         len = vasprintf(&buf, fmt, ap);
  68         if (len < 0)
  69                 goto out;
  70
  71         if (ms->o.buf != NULL) {
  72                 len = asprintf(&newstr, "%s%s", ms->o.buf, buf);
  73                 free(buf);
  74                 if (len < 0)
  75                         goto out;
  76                 free(ms->o.buf);
  77                 buf = newstr;
  78         }
  79         ms->o.buf = buf;
  80         return 0;
  81 out:
  82         file_error(ms, errno, "vasprintf failed");
  83         return -1;
  84 }
  85
  86 protected int
  87 file_printf(struct magic_set *ms, const char *fmt, ...)
  88 {
  89         int rv;
  90         va_list ap;
  91
  92         va_start(ap, fmt);
  93         rv = file_vprintf(ms, fmt, ap);
  94         va_end(ap);
  95         return rv;
  96 }
  97
  98 /*
  99  * error - print best error message possible
 100  */
 101 /*VARARGS*/
 102 private void
 103 file_error_core(struct magic_set *ms, int error, const char *f, va_list va,
 104     size_t lineno)
 105 {
 106         /* Only the first error is ok */
 107         if (ms->event_flags & EVENT_HAD_ERR)
 108                 return;
 109         if (lineno != 0) {
 110                 free(ms->o.buf);
 111                 ms->o.buf = NULL;
 112                 file_printf(ms, "line %zu: ", lineno);
 113         }
 114         file_vprintf(ms, f, va);
 115         if (error > 0)
 116                 file_printf(ms, " (%s)", strerror(error));
 117         ms->event_flags |= EVENT_HAD_ERR;
 118         ms->error = error;
 119 }
 120
 121 /*VARARGS*/
 122 protected void
 123 file_error(struct magic_set *ms, int error, const char *f, ...)
 124 {
 125         va_list va;
 126         va_start(va, f);
 127         file_error_core(ms, error, f, va, 0);
 128         va_end(va);
 129 }
 130
 131 /*
 132  * Print an error with magic line number.
 133  */
 134 /*VARARGS*/
 135 protected void
 136 file_magerror(struct magic_set *ms, const char *f, ...)
 137 {
 138         va_list va;
 139         va_start(va, f);
 140         file_error_core(ms, 0, f, va, ms->line);
 141         va_end(va);
 142 }
 143
 144 protected void
 145 file_oomem(struct magic_set *ms, size_t len)
 146 {
 147         file_error(ms, errno, "cannot allocate %zu bytes", len);
 148 }
 149
 150 protected void
 151 file_badseek(struct magic_set *ms)
 152 {
 153         file_error(ms, errno, "error seeking");
 154 }
 155
 156 protected void
 157 file_badread(struct magic_set *ms)
 158 {
 159         file_error(ms, errno, "error reading");
 160 }
 161
 162 #ifndef COMPILE_ONLY
 163 protected int
 164 file_buffer(struct magic_set *ms, int fd, const char *inname, const void *buf,
 165     size_t nb)
 166 {
 167         int m = 0, rv = 0, looks_text = 0;
 168         int mime = ms->flags & MAGIC_MIME;
 169         const unsigned char *ubuf = CAST(const unsigned char *, buf);
 170         unichar *u8buf = NULL;
 171         size_t ulen;
 172         const char *code = NULL;
 173         const char *code_mime = "binary";
 174         const char *type = NULL;
 175
 176
 177
 178         if (nb == 0) {
 179                 if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
 180                     file_printf(ms, mime ? "application/x-empty" :
 181                     "empty") == -1)
 182                         return -1;
 183                 return 1;
 184         } else if (nb == 1) {
 185                 if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
 186                     file_printf(ms, mime ? "application/octet-stream" :
 187                     "very short file (no magic)") == -1)
 188                         return -1;
 189                 return 1;
 190         }
 191
 192         if ((ms->flags & MAGIC_NO_CHECK_ENCODING) == 0) {
 193                 looks_text = file_encoding(ms, ubuf, nb, &u8buf, &ulen,
 194                     &code, &code_mime, &type);
 195         }
 196
 197 #ifdef __EMX__
 198         if ((ms->flags & MAGIC_NO_CHECK_APPTYPE) == 0 && inname) {
 199                 switch (file_os2_apptype(ms, inname, buf, nb)) {
 200                 case -1:
 201                         return -1;
 202                 case 0:
 203                         break;
 204                 default:
 205                         return 1;
 206                 }
 207         }
 208 #endif
 209
 210         /* try compression stuff */
 211         if ((ms->flags & MAGIC_NO_CHECK_COMPRESS) == 0)
 212                 if ((m = file_zmagic(ms, fd, inname, ubuf, nb)) != 0) {
 213                         if ((ms->flags & MAGIC_DEBUG) != 0)
 214                                 (void)fprintf(stderr, "zmagic %d\n", m);
 215                         goto done;
 216                 }
 217
 218         /* Check if we have a tar file */
 219         if ((ms->flags & MAGIC_NO_CHECK_TAR) == 0)
 220                 if ((m = file_is_tar(ms, ubuf, nb)) != 0) {
 221                         if ((ms->flags & MAGIC_DEBUG) != 0)
 222                                 (void)fprintf(stderr, "tar %d\n", m);
 223                         goto done;
 224                 }
 225
 226         /* Check if we have a CDF file */
 227         if ((ms->flags & MAGIC_NO_CHECK_CDF) == 0)
 228                 if ((m = file_trycdf(ms, fd, ubuf, nb)) != 0) {
 229                         if ((ms->flags & MAGIC_DEBUG) != 0)
 230                                 (void)fprintf(stderr, "cdf %d\n", m);
 231                         goto done;
 232                 }
 233
 234         /* try soft magic tests */
 235         if ((ms->flags & MAGIC_NO_CHECK_SOFT) == 0)
 236                 if ((m = file_softmagic(ms, ubuf, nb, BINTEST)) != 0) {
 237                         if ((ms->flags & MAGIC_DEBUG) != 0)
 238                                 (void)fprintf(stderr, "softmagic %d\n", m);
 239 #ifdef BUILTIN_ELF
 240                         if ((ms->flags & MAGIC_NO_CHECK_ELF) == 0 && m == 1 &&
 241                             nb > 5 && fd != -1) {
 242                                 /*
 243                                  * We matched something in the file, so this
 244                                  * *might* be an ELF file, and the file is at
 245                                  * least 5 bytes long, so if it's an ELF file
 246                                  * it has at least one byte past the ELF magic
 247                                  * number - try extracting information from the
 248                                  * ELF headers that cannot easily * be
 249                                  * extracted with rules in the magic file.
 250                                  */
 251                                 if ((m = file_tryelf(ms, fd, ubuf, nb)) != 0)
 252                                         if ((ms->flags & MAGIC_DEBUG) != 0)
 253                                                 (void)fprintf(stderr,
 254                                                     "elf %d\n", m);
 255                         }
 256 #endif
 257                         goto done;
 258                 }
 259
 260         /* try text properties (and possibly text tokens) */
 261         if ((ms->flags & MAGIC_NO_CHECK_TEXT) == 0) {
 262
 263                 if ((m = file_ascmagic(ms, ubuf, nb)) != 0) {
 264                         if ((ms->flags & MAGIC_DEBUG) != 0)
 265                                 (void)fprintf(stderr, "ascmagic %d\n", m);
 266                         goto done;
 267                 }
 268
 269                 /* try to discover text encoding */
 270                 if ((ms->flags & MAGIC_NO_CHECK_ENCODING) == 0) {
 271                         if (looks_text == 0)
 272                                 if ((m = file_ascmagic_with_encoding( ms, ubuf,
 273                                     nb, u8buf, ulen, code, type)) != 0) {
 274                                         if ((ms->flags & MAGIC_DEBUG) != 0)
 275                                                 (void)fprintf(stderr,
 276                                                     "ascmagic/enc %d\n", m);
 277                                         goto done;
 278                                 }
 279                 }
 280         }
 281
 282         /* give up */
 283         m = 1;
 284         if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
 285             file_printf(ms, mime ? "application/octet-stream" : "data") == -1) {
 286             rv = -1;
 287         }
 288  done:
 289         if ((ms->flags & MAGIC_MIME_ENCODING) != 0) {
 290                 if (ms->flags & MAGIC_MIME_TYPE)
 291                         if (file_printf(ms, "; charset=") == -1)
 292                                 rv = -1;
 293                 if (file_printf(ms, "%s", code_mime) == -1)
 294                         rv = -1;
 295         }
 296         if (u8buf)
 297                 free(u8buf);
 298         if (rv)
 299                 return rv;
 300
 301         return m;
 302 }
 303 #endif
 304
 305 protected int
 306 file_reset(struct magic_set *ms)
 307 {
 308         if (ms->mlist == NULL) {
 309                 file_error(ms, 0, "no magic files loaded");
 310                 return -1;
 311         }
 312         if (ms->o.buf) {
 313                 free(ms->o.buf);
 314                 ms->o.buf = NULL;
 315         }
 316         if (ms->o.pbuf) {
 317                 free(ms->o.pbuf);
 318                 ms->o.pbuf = NULL;
 319         }
 320         ms->event_flags &= ~EVENT_HAD_ERR;
 321         ms->error = -1;
 322         return 0;
 323 }
 324
 325 #define OCTALIFY(n, o)  \
 326         /*LINTED*/ \
 327         (void)(*(n)++ = '\\', \
 328         *(n)++ = (((uint32_t)*(o) >> 6) & 3) + '0', \
 329         *(n)++ = (((uint32_t)*(o) >> 3) & 7) + '0', \
 330         *(n)++ = (((uint32_t)*(o) >> 0) & 7) + '0', \
 331         (o)++)
 332
 333 protected const char *
 334 file_getbuffer(struct magic_set *ms)
 335 {
 336         char *pbuf, *op, *np;
 337         size_t psize, len;
 338
 339         if (ms->event_flags & EVENT_HAD_ERR)
 340                 return NULL;
 341
 342         if (ms->flags & MAGIC_RAW)
 343                 return ms->o.buf;
 344
 345         if (ms->o.buf == NULL)
 346                 return NULL;
 347
 348         /* * 4 is for octal representation, + 1 is for NUL */
 349         len = strlen(ms->o.buf);
 350         if (len > (SIZE_MAX - 1) / 4) {
 351                 file_oomem(ms, len);
 352                 return NULL;
 353         }
 354         psize = len * 4 + 1;
 355         if ((pbuf = CAST(char *, realloc(ms->o.pbuf, psize))) == NULL) {
 356                 file_oomem(ms, psize);
 357                 return NULL;
 358         }
 359         ms->o.pbuf = pbuf;
 360
 361 #if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH)
 362         {
 363                 mbstate_t state;
 364                 wchar_t nextchar;
 365                 int mb_conv = 1;
 366                 size_t bytesconsumed;
 367                 char *eop;
 368                 (void)memset(&state, 0, sizeof(mbstate_t));
 369
 370                 np = ms->o.pbuf;
 371                 op = ms->o.buf;
 372                 eop = op + len;
 373
 374                 while (op < eop) {
 375                         bytesconsumed = mbrtowc(&nextchar, op,
 376                             (size_t)(eop - op), &state);
 377                         if (bytesconsumed == (size_t)(-1) ||
 378                             bytesconsumed == (size_t)(-2)) {
 379                                 mb_conv = 0;
 380                                 break;
 381                         }
 382
 383                         if (iswprint(nextchar)) {
 384                                 (void)memcpy(np, op, bytesconsumed);
 385                                 op += bytesconsumed;
 386                                 np += bytesconsumed;
 387                         } else {
 388                                 while (bytesconsumed-- > 0)
 389                                         OCTALIFY(np, op);
 390                         }
 391                 }
 392                 *np = '\0';
 393
 394                 /* Parsing succeeded as a multi-byte sequence */
 395                 if (mb_conv != 0)
 396                         return ms->o.pbuf;
 397         }
 398 #endif
 399
 400         for (np = ms->o.pbuf, op = ms->o.buf; *op; op++) {
 401                 if (isprint((unsigned char)*op)) {
 402                         *np++ = *op;
 403                 } else {
 404                         OCTALIFY(np, op);
 405                 }
 406         }
 407         *np = '\0';
 408         return ms->o.pbuf;
 409 }
 410
 411 protected int
 412 file_check_mem(struct magic_set *ms, unsigned int level)
 413 {
 414         size_t len;
 415
 416         if (level >= ms->c.len) {
 417                 len = (ms->c.len += 20) * sizeof(*ms->c.li);
 418                 ms->c.li = CAST(struct level_info *, (ms->c.li == NULL) ?
 419                     malloc(len) :
 420                     realloc(ms->c.li, len));
 421                 if (ms->c.li == NULL) {
 422                         file_oomem(ms, len);
 423                         return -1;
 424                 }
 425         }
 426         ms->c.li[level].got_match = 0;
 427 #ifdef ENABLE_CONDITIONALS
 428         ms->c.li[level].last_match = 0;
 429         ms->c.li[level].last_cond = COND_NONE;
 430 #endif /* ENABLE_CONDITIONALS */
 431         return 0;
 432 }