contrib/file/src/readelf.c

   1 /*
   2  * Copyright (c) Christos Zoulas 2003.
   3  * All Rights Reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   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.
  14  *
  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
  25  * SUCH DAMAGE.
  26  */
  27 #include "file.h"
  28
  29 #ifndef lint
  30 FILE_RCSID("@(#)$File: readelf.c,v 1.111 2014/12/09 02:47:45 christos Exp $")
  31 #endif
  32
  33 #ifdef BUILTIN_ELF
  34 #include <string.h>
  35 #include <ctype.h>
  36 #include <stdlib.h>
  37 #ifdef HAVE_UNISTD_H
  38 #include <unistd.h>
  39 #endif
  40
  41 #include "readelf.h"
  42 #include "magic.h"
  43
  44 #ifdef  ELFCORE
  45 private int dophn_core(struct magic_set *, int, int, int, off_t, int, size_t,
  46     off_t, int *);
  47 #endif
  48 private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t,
  49     off_t, int *, int);
  50 private int doshn(struct magic_set *, int, int, int, off_t, int, size_t,
  51     off_t, int *, int, int);
  52 private size_t donote(struct magic_set *, void *, size_t, size_t, int,
  53     int, size_t, int *);
  54
  55 #define ELF_ALIGN(a)    ((((a) + align - 1) / align) * align)
  56
  57 #define isquote(c) (strchr("'\"`", (c)) != NULL)
  58
  59 private uint16_t getu16(int, uint16_t);
  60 private uint32_t getu32(int, uint32_t);
  61 private uint64_t getu64(int, uint64_t);
  62
  63 #define MAX_PHNUM       128
  64 #define MAX_SHNUM       32768
  65 #define SIZE_UNKNOWN    ((off_t)-1)
  66
  67 private int
  68 toomany(struct magic_set *ms, const char *name, uint16_t num)
  69 {
  70         if (file_printf(ms, ", too many %s header sections (%u)", name, num
  71             ) == -1)
  72                 return -1;
  73         return 0;
  74 }
  75
  76 private uint16_t
  77 getu16(int swap, uint16_t value)
  78 {
  79         union {
  80                 uint16_t ui;
  81                 char c[2];
  82         } retval, tmpval;
  83
  84         if (swap) {
  85                 tmpval.ui = value;
  86
  87                 retval.c[0] = tmpval.c[1];
  88                 retval.c[1] = tmpval.c[0];
  89
  90                 return retval.ui;
  91         } else
  92                 return value;
  93 }
  94
  95 private uint32_t
  96 getu32(int swap, uint32_t value)
  97 {
  98         union {
  99                 uint32_t ui;
 100                 char c[4];
 101         } retval, tmpval;
 102
 103         if (swap) {
 104                 tmpval.ui = value;
 105
 106                 retval.c[0] = tmpval.c[3];
 107                 retval.c[1] = tmpval.c[2];
 108                 retval.c[2] = tmpval.c[1];
 109                 retval.c[3] = tmpval.c[0];
 110
 111                 return retval.ui;
 112         } else
 113                 return value;
 114 }
 115
 116 private uint64_t
 117 getu64(int swap, uint64_t value)
 118 {
 119         union {
 120                 uint64_t ui;
 121                 char c[8];
 122         } retval, tmpval;
 123
 124         if (swap) {
 125                 tmpval.ui = value;
 126
 127                 retval.c[0] = tmpval.c[7];
 128                 retval.c[1] = tmpval.c[6];
 129                 retval.c[2] = tmpval.c[5];
 130                 retval.c[3] = tmpval.c[4];
 131                 retval.c[4] = tmpval.c[3];
 132                 retval.c[5] = tmpval.c[2];
 133                 retval.c[6] = tmpval.c[1];
 134                 retval.c[7] = tmpval.c[0];
 135
 136                 return retval.ui;
 137         } else
 138                 return value;
 139 }
 140
 141 #define elf_getu16(swap, value) getu16(swap, value)
 142 #define elf_getu32(swap, value) getu32(swap, value)
 143 #define elf_getu64(swap, value) getu64(swap, value)
 144
 145 #define xsh_addr        (clazz == ELFCLASS32                    \
 146                          ? (void *)&sh32                        \
 147                          : (void *)&sh64)
 148 #define xsh_sizeof      (clazz == ELFCLASS32                    \
 149                          ? sizeof(sh32)                         \
 150                          : sizeof(sh64))
 151 #define xsh_size        (size_t)(clazz == ELFCLASS32            \
 152                          ? elf_getu32(swap, sh32.sh_size)       \
 153                          : elf_getu64(swap, sh64.sh_size))
 154 #define xsh_offset      (off_t)(clazz == ELFCLASS32             \
 155                          ? elf_getu32(swap, sh32.sh_offset)     \
 156                          : elf_getu64(swap, sh64.sh_offset))
 157 #define xsh_type        (clazz == ELFCLASS32                    \
 158                          ? elf_getu32(swap, sh32.sh_type)       \
 159                          : elf_getu32(swap, sh64.sh_type))
 160 #define xsh_name        (clazz == ELFCLASS32                    \
 161                          ? elf_getu32(swap, sh32.sh_name)       \
 162                          : elf_getu32(swap, sh64.sh_name))
 163 #define xph_addr        (clazz == ELFCLASS32                    \
 164                          ? (void *) &ph32                       \
 165                          : (void *) &ph64)
 166 #define xph_sizeof      (clazz == ELFCLASS32                    \
 167                          ? sizeof(ph32)                         \
 168                          : sizeof(ph64))
 169 #define xph_type        (clazz == ELFCLASS32                    \
 170                          ? elf_getu32(swap, ph32.p_type)        \
 171                          : elf_getu32(swap, ph64.p_type))
 172 #define xph_offset      (off_t)(clazz == ELFCLASS32             \
 173                          ? elf_getu32(swap, ph32.p_offset)      \
 174                          : elf_getu64(swap, ph64.p_offset))
 175 #define xph_align       (size_t)((clazz == ELFCLASS32           \
 176                          ? (off_t) (ph32.p_align ?              \
 177                             elf_getu32(swap, ph32.p_align) : 4) \
 178                          : (off_t) (ph64.p_align ?              \
 179                             elf_getu64(swap, ph64.p_align) : 4)))
 180 #define xph_filesz      (size_t)((clazz == ELFCLASS32           \
 181                          ? elf_getu32(swap, ph32.p_filesz)      \
 182                          : elf_getu64(swap, ph64.p_filesz)))
 183 #define xnh_addr        (clazz == ELFCLASS32                    \
 184                          ? (void *)&nh32                        \
 185                          : (void *)&nh64)
 186 #define xph_memsz       (size_t)((clazz == ELFCLASS32           \
 187                          ? elf_getu32(swap, ph32.p_memsz)       \
 188                          : elf_getu64(swap, ph64.p_memsz)))
 189 #define xnh_sizeof      (clazz == ELFCLASS32                    \
 190                          ? sizeof nh32                          \
 191                          : sizeof nh64)
 192 #define xnh_type        (clazz == ELFCLASS32                    \
 193                          ? elf_getu32(swap, nh32.n_type)        \
 194                          : elf_getu32(swap, nh64.n_type))
 195 #define xnh_namesz      (clazz == ELFCLASS32                    \
 196                          ? elf_getu32(swap, nh32.n_namesz)      \
 197                          : elf_getu32(swap, nh64.n_namesz))
 198 #define xnh_descsz      (clazz == ELFCLASS32                    \
 199                          ? elf_getu32(swap, nh32.n_descsz)      \
 200                          : elf_getu32(swap, nh64.n_descsz))
 201 #define prpsoffsets(i)  (clazz == ELFCLASS32                    \
 202                          ? prpsoffsets32[i]                     \
 203                          : prpsoffsets64[i])
 204 #define xcap_addr       (clazz == ELFCLASS32                    \
 205                          ? (void *)&cap32                       \
 206                          : (void *)&cap64)
 207 #define xcap_sizeof     (clazz == ELFCLASS32                    \
 208                          ? sizeof cap32                         \
 209                          : sizeof cap64)
 210 #define xcap_tag        (clazz == ELFCLASS32                    \
 211                          ? elf_getu32(swap, cap32.c_tag)        \
 212                          : elf_getu64(swap, cap64.c_tag))
 213 #define xcap_val        (clazz == ELFCLASS32                    \
 214                          ? elf_getu32(swap, cap32.c_un.c_val)   \
 215                          : elf_getu64(swap, cap64.c_un.c_val))
 216
 217 #ifdef ELFCORE
 218 /*
 219  * Try larger offsets first to avoid false matches
 220  * from earlier data that happen to look like strings.
 221  */
 222 static const size_t     prpsoffsets32[] = {
 223 #ifdef USE_NT_PSINFO
 224         104,            /* SunOS 5.x (command line) */
 225         88,             /* SunOS 5.x (short name) */
 226 #endif /* USE_NT_PSINFO */
 227
 228         100,            /* SunOS 5.x (command line) */
 229         84,             /* SunOS 5.x (short name) */
 230
 231         44,             /* Linux (command line) */
 232         28,             /* Linux 2.0.36 (short name) */
 233
 234         8,              /* FreeBSD */
 235 };
 236
 237 static const size_t     prpsoffsets64[] = {
 238 #ifdef USE_NT_PSINFO
 239         152,            /* SunOS 5.x (command line) */
 240         136,            /* SunOS 5.x (short name) */
 241 #endif /* USE_NT_PSINFO */
 242
 243         136,            /* SunOS 5.x, 64-bit (command line) */
 244         120,            /* SunOS 5.x, 64-bit (short name) */
 245
 246         56,             /* Linux (command line) */
 247         40,             /* Linux (tested on core from 2.4.x, short name) */
 248
 249         16,             /* FreeBSD, 64-bit */
 250 };
 251
 252 #define NOFFSETS32      (sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
 253 #define NOFFSETS64      (sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
 254
 255 #define NOFFSETS        (clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
 256
 257 /*
 258  * Look through the program headers of an executable image, searching
 259  * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
 260  * "FreeBSD"; if one is found, try looking in various places in its
 261  * contents for a 16-character string containing only printable
 262  * characters - if found, that string should be the name of the program
 263  * that dropped core.  Note: right after that 16-character string is,
 264  * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
 265  * Linux, a longer string (80 characters, in 5.x, probably other
 266  * SVR4-flavored systems, and Linux) containing the start of the
 267  * command line for that program.
 268  *
 269  * SunOS 5.x core files contain two PT_NOTE sections, with the types
 270  * NT_PRPSINFO (old) and NT_PSINFO (new).  These structs contain the
 271  * same info about the command name and command line, so it probably
 272  * isn't worthwhile to look for NT_PSINFO, but the offsets are provided
 273  * above (see USE_NT_PSINFO), in case we ever decide to do so.  The
 274  * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent;
 275  * the SunOS 5.x file command relies on this (and prefers the latter).
 276  *
 277  * The signal number probably appears in a section of type NT_PRSTATUS,
 278  * but that's also rather OS-dependent, in ways that are harder to
 279  * dissect with heuristics, so I'm not bothering with the signal number.
 280  * (I suppose the signal number could be of interest in situations where
 281  * you don't have the binary of the program that dropped core; if you
 282  * *do* have that binary, the debugger will probably tell you what
 283  * signal it was.)
 284  */
 285
 286 #define OS_STYLE_SVR4           0
 287 #define OS_STYLE_FREEBSD        1
 288 #define OS_STYLE_NETBSD         2
 289
 290 private const char os_style_names[][8] = {
 291         "SVR4",
 292         "FreeBSD",
 293         "NetBSD",
 294 };
 295
 296 #define FLAGS_DID_CORE          0x01
 297 #define FLAGS_DID_NOTE          0x02
 298 #define FLAGS_DID_BUILD_ID      0x04
 299 #define FLAGS_DID_CORE_STYLE    0x08
 300 #define FLAGS_IS_CORE           0x10
 301
 302 private int
 303 dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
 304     int num, size_t size, off_t fsize, int *flags)
 305 {
 306         Elf32_Phdr ph32;
 307         Elf64_Phdr ph64;
 308         size_t offset, len;
 309         unsigned char nbuf[BUFSIZ];
 310         ssize_t bufsize;
 311
 312         if (size != xph_sizeof) {
 313                 if (file_printf(ms, ", corrupted program header size") == -1)
 314                         return -1;
 315                 return 0;
 316         }
 317
 318         /*
 319          * Loop through all the program headers.
 320          */
 321         for ( ; num; num--) {
 322                 if (pread(fd, xph_addr, xph_sizeof, off) == -1) {
 323                         file_badread(ms);
 324                         return -1;
 325                 }
 326                 off += size;
 327
 328                 if (fsize != SIZE_UNKNOWN && xph_offset > fsize) {
 329                         /* Perhaps warn here */
 330                         continue;
 331                 }
 332
 333                 if (xph_type != PT_NOTE)
 334                         continue;
 335
 336                 /*
 337                  * This is a PT_NOTE section; loop through all the notes
 338                  * in the section.
 339                  */
 340                 len = xph_filesz < sizeof(nbuf) ? xph_filesz : sizeof(nbuf);
 341                 if ((bufsize = pread(fd, nbuf, len, xph_offset)) == -1) {
 342                         file_badread(ms);
 343                         return -1;
 344                 }
 345                 offset = 0;
 346                 for (;;) {
 347                         if (offset >= (size_t)bufsize)
 348                                 break;
 349                         offset = donote(ms, nbuf, offset, (size_t)bufsize,
 350                             clazz, swap, 4, flags);
 351                         if (offset == 0)
 352                                 break;
 353
 354                 }
 355         }
 356         return 0;
 357 }
 358 #endif
 359
 360 static void
 361 do_note_netbsd_version(struct magic_set *ms, int swap, void *v)
 362 {
 363         uint32_t desc;
 364         (void)memcpy(&desc, v, sizeof(desc));
 365         desc = elf_getu32(swap, desc);
 366
 367         if (file_printf(ms, ", for NetBSD") == -1)
 368                 return;
 369         /*
 370          * The version number used to be stuck as 199905, and was thus
 371          * basically content-free.  Newer versions of NetBSD have fixed
 372          * this and now use the encoding of __NetBSD_Version__:
 373          *
 374          *      MMmmrrpp00
 375          *
 376          * M = major version
 377          * m = minor version
 378          * r = release ["",A-Z,Z[A-Z] but numeric]
 379          * p = patchlevel
 380          */
 381         if (desc > 100000000U) {
 382                 uint32_t ver_patch = (desc / 100) % 100;
 383                 uint32_t ver_rel = (desc / 10000) % 100;
 384                 uint32_t ver_min = (desc / 1000000) % 100;
 385                 uint32_t ver_maj = desc / 100000000;
 386
 387                 if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1)
 388                         return;
 389                 if (ver_rel == 0 && ver_patch != 0) {
 390                         if (file_printf(ms, ".%u", ver_patch) == -1)
 391                                 return;
 392                 } else if (ver_rel != 0) {
 393                         while (ver_rel > 26) {
 394                                 if (file_printf(ms, "Z") == -1)
 395                                         return;
 396                                 ver_rel -= 26;
 397                         }
 398                         if (file_printf(ms, "%c", 'A' + ver_rel - 1)
 399                             == -1)
 400                                 return;
 401                 }
 402         }
 403 }
 404
 405 static void
 406 do_note_freebsd_version(struct magic_set *ms, int swap, void *v)
 407 {
 408         uint32_t desc;
 409
 410         (void)memcpy(&desc, v, sizeof(desc));
 411         desc = elf_getu32(swap, desc);
 412         if (file_printf(ms, ", for FreeBSD") == -1)
 413                 return;
 414
 415         /*
 416          * Contents is __FreeBSD_version, whose relation to OS
 417          * versions is defined by a huge table in the Porter's
 418          * Handbook.  This is the general scheme:
 419          *
 420          * Releases:
 421          *      Mmp000 (before 4.10)
 422          *      Mmi0p0 (before 5.0)
 423          *      Mmm0p0
 424          *
 425          * Development branches:
 426          *      Mmpxxx (before 4.6)
 427          *      Mmp1xx (before 4.10)
 428          *      Mmi1xx (before 5.0)
 429          *      M000xx (pre-M.0)
 430          *      Mmm1xx
 431          *
 432          * M = major version
 433          * m = minor version
 434          * i = minor version increment (491000 -> 4.10)
 435          * p = patchlevel
 436          * x = revision
 437          *
 438          * The first release of FreeBSD to use ELF by default
 439          * was version 3.0.
 440          */
 441         if (desc == 460002) {
 442                 if (file_printf(ms, " 4.6.2") == -1)
 443                         return;
 444         } else if (desc < 460100) {
 445                 if (file_printf(ms, " %d.%d", desc / 100000,
 446                     desc / 10000 % 10) == -1)
 447                         return;
 448                 if (desc / 1000 % 10 > 0)
 449                         if (file_printf(ms, ".%d", desc / 1000 % 10) == -1)
 450                                 return;
 451                 if ((desc % 1000 > 0) || (desc % 100000 == 0))
 452                         if (file_printf(ms, " (%d)", desc) == -1)
 453                                 return;
 454         } else if (desc < 500000) {
 455                 if (file_printf(ms, " %d.%d", desc / 100000,
 456                     desc / 10000 % 10 + desc / 1000 % 10) == -1)
 457                         return;
 458                 if (desc / 100 % 10 > 0) {
 459                         if (file_printf(ms, " (%d)", desc) == -1)
 460                                 return;
 461                 } else if (desc / 10 % 10 > 0) {
 462                         if (file_printf(ms, ".%d", desc / 10 % 10) == -1)
 463                                 return;
 464                 }
 465         } else {
 466                 if (file_printf(ms, " %d.%d", desc / 100000,
 467                     desc / 1000 % 100) == -1)
 468                         return;
 469                 if ((desc / 100 % 10 > 0) ||
 470                     (desc % 100000 / 100 == 0)) {
 471                         if (file_printf(ms, " (%d)", desc) == -1)
 472                                 return;
 473                 } else if (desc / 10 % 10 > 0) {
 474                         if (file_printf(ms, ".%d", desc / 10 % 10) == -1)
 475                                 return;
 476                 }
 477         }
 478 }
 479
 480 private size_t
 481 donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
 482     int clazz, int swap, size_t align, int *flags)
 483 {
 484         Elf32_Nhdr nh32;
 485         Elf64_Nhdr nh64;
 486         size_t noff, doff;
 487 #ifdef ELFCORE
 488         int os_style = -1;
 489 #endif
 490         uint32_t namesz, descsz;
 491         unsigned char *nbuf = CAST(unsigned char *, vbuf);
 492
 493         if (xnh_sizeof + offset > size) {
 494                 /*
 495                  * We're out of note headers.
 496                  */
 497                 return xnh_sizeof + offset;
 498         }
 499
 500         (void)memcpy(xnh_addr, &nbuf[offset], xnh_sizeof);
 501         offset += xnh_sizeof;
 502
 503         namesz = xnh_namesz;
 504         descsz = xnh_descsz;
 505         if ((namesz == 0) && (descsz == 0)) {
 506                 /*
 507                  * We're out of note headers.
 508                  */
 509                 return (offset >= size) ? offset : size;
 510         }
 511
 512         if (namesz & 0x80000000) {
 513             (void)file_printf(ms, ", bad note name size 0x%lx",
 514                 (unsigned long)namesz);
 515             return 0;
 516         }
 517
 518         if (descsz & 0x80000000) {
 519             (void)file_printf(ms, ", bad note description size 0x%lx",
 520                 (unsigned long)descsz);
 521             return 0;
 522         }
 523
 524
 525         noff = offset;
 526         doff = ELF_ALIGN(offset + namesz);
 527
 528         if (offset + namesz > size) {
 529                 /*
 530                  * We're past the end of the buffer.
 531                  */
 532                 return doff;
 533         }
 534
 535         offset = ELF_ALIGN(doff + descsz);
 536         if (doff + descsz > size) {
 537                 /*
 538                  * We're past the end of the buffer.
 539                  */
 540                 return (offset >= size) ? offset : size;
 541         }
 542
 543         if ((*flags & (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID)) ==
 544             (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID))
 545                 goto core;
 546
 547         if (namesz == 5 && strcmp((char *)&nbuf[noff], "SuSE") == 0 &&
 548             xnh_type == NT_GNU_VERSION && descsz == 2) {
 549             file_printf(ms, ", for SuSE %d.%d", nbuf[doff], nbuf[doff + 1]);
 550         }
 551         if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
 552             xnh_type == NT_GNU_VERSION && descsz == 16) {
 553                 uint32_t desc[4];
 554                 (void)memcpy(desc, &nbuf[doff], sizeof(desc));
 555
 556                 if (file_printf(ms, ", for GNU/") == -1)
 557                         return size;
 558                 switch (elf_getu32(swap, desc[0])) {
 559                 case GNU_OS_LINUX:
 560                         if (file_printf(ms, "Linux") == -1)
 561                                 return size;
 562                         break;
 563                 case GNU_OS_HURD:
 564                         if (file_printf(ms, "Hurd") == -1)
 565                                 return size;
 566                         break;
 567                 case GNU_OS_SOLARIS:
 568                         if (file_printf(ms, "Solaris") == -1)
 569                                 return size;
 570                         break;
 571                 case GNU_OS_KFREEBSD:
 572                         if (file_printf(ms, "kFreeBSD") == -1)
 573                                 return size;
 574                         break;
 575                 case GNU_OS_KNETBSD:
 576                         if (file_printf(ms, "kNetBSD") == -1)
 577                                 return size;
 578                         break;
 579                 default:
 580                         if (file_printf(ms, "<unknown>") == -1)
 581                                 return size;
 582                 }
 583                 if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]),
 584                     elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1)
 585                         return size;
 586                 *flags |= FLAGS_DID_NOTE;
 587                 return size;
 588         }
 589
 590         if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
 591             xnh_type == NT_GNU_BUILD_ID && (descsz == 16 || descsz == 20)) {
 592             uint8_t desc[20];
 593             uint32_t i;
 594             if (file_printf(ms, ", BuildID[%s]=", descsz == 16 ? "md5/uuid" :
 595                 "sha1") == -1)
 596                     return size;
 597             (void)memcpy(desc, &nbuf[doff], descsz);
 598             for (i = 0; i < descsz; i++)
 599                 if (file_printf(ms, "%02x", desc[i]) == -1)
 600                     return size;
 601             *flags |= FLAGS_DID_BUILD_ID;
 602         }
 603
 604         if (namesz == 4 && strcmp((char *)&nbuf[noff], "PaX") == 0 &&
 605             xnh_type == NT_NETBSD_PAX && descsz == 4) {
 606                 static const char *pax[] = {
 607                     "+mprotect",
 608                     "-mprotect",
 609                     "+segvguard",
 610                     "-segvguard",
 611                     "+ASLR",
 612                     "-ASLR",
 613                 };
 614                 uint32_t desc;
 615                 size_t i;
 616                 int did = 0;
 617
 618                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 619                 desc = elf_getu32(swap, desc);
 620
 621                 if (desc && file_printf(ms, ", PaX: ") == -1)
 622                         return size;
 623
 624                 for (i = 0; i < __arraycount(pax); i++) {
 625                         if (((1 << i) & desc) == 0)
 626                                 continue;
 627                         if (file_printf(ms, "%s%s", did++ ? "," : "",
 628                             pax[i]) == -1)
 629                                 return size;
 630                 }
 631         }
 632
 633         if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0) {
 634                 switch (xnh_type) {
 635                 case NT_NETBSD_VERSION:
 636                         if (descsz == 4) {
 637                                 do_note_netbsd_version(ms, swap, &nbuf[doff]);
 638                                 *flags |= FLAGS_DID_NOTE;
 639                                 return size;
 640                         }
 641                         break;
 642                 case NT_NETBSD_MARCH:
 643                         if (file_printf(ms, ", compiled for: %.*s", (int)descsz,
 644                             (const char *)&nbuf[doff]) == -1)
 645                                 return size;
 646                         break;
 647                 case NT_NETBSD_CMODEL:
 648                         if (file_printf(ms, ", compiler model: %.*s",
 649                             (int)descsz, (const char *)&nbuf[doff]) == -1)
 650                                 return size;
 651                         break;
 652                 default:
 653                         if (file_printf(ms, ", note=%u", xnh_type) == -1)
 654                                 return size;
 655                         break;
 656                 }
 657                 return size;
 658         }
 659
 660         if (namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0) {
 661                 if (xnh_type == NT_FREEBSD_VERSION && descsz == 4) {
 662                         do_note_freebsd_version(ms, swap, &nbuf[doff]);
 663                         *flags |= FLAGS_DID_NOTE;
 664                         return size;
 665                 }
 666         }
 667
 668         if (namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 &&
 669             xnh_type == NT_OPENBSD_VERSION && descsz == 4) {
 670                 if (file_printf(ms, ", for OpenBSD") == -1)
 671                         return size;
 672                 /* Content of note is always 0 */
 673                 *flags |= FLAGS_DID_NOTE;
 674                 return size;
 675         }
 676
 677         if (namesz == 10 && strcmp((char *)&nbuf[noff], "DragonFly") == 0 &&
 678             xnh_type == NT_DRAGONFLY_VERSION && descsz == 4) {
 679                 uint32_t desc;
 680                 if (file_printf(ms, ", for DragonFly") == -1)
 681                         return size;
 682                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 683                 desc = elf_getu32(swap, desc);
 684                 if (file_printf(ms, " %d.%d.%d", desc / 100000,
 685                     desc / 10000 % 10, desc % 10000) == -1)
 686                         return size;
 687                 *flags |= FLAGS_DID_NOTE;
 688                 return size;
 689         }
 690
 691 core:
 692         /*
 693          * Sigh.  The 2.0.36 kernel in Debian 2.1, at
 694          * least, doesn't correctly implement name
 695          * sections, in core dumps, as specified by
 696          * the "Program Linking" section of "UNIX(R) System
 697          * V Release 4 Programmer's Guide: ANSI C and
 698          * Programming Support Tools", because my copy
 699          * clearly says "The first 'namesz' bytes in 'name'
 700          * contain a *null-terminated* [emphasis mine]
 701          * character representation of the entry's owner
 702          * or originator", but the 2.0.36 kernel code
 703          * doesn't include the terminating null in the
 704          * name....
 705          */
 706         if ((namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) ||
 707             (namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) {
 708                 os_style = OS_STYLE_SVR4;
 709         }
 710
 711         if ((namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) {
 712                 os_style = OS_STYLE_FREEBSD;
 713         }
 714
 715         if ((namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11)
 716             == 0)) {
 717                 os_style = OS_STYLE_NETBSD;
 718         }
 719
 720 #ifdef ELFCORE
 721         if ((*flags & FLAGS_DID_CORE) != 0)
 722                 return size;
 723
 724         if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) {
 725                 if (file_printf(ms, ", %s-style", os_style_names[os_style])
 726                     == -1)
 727                         return size;
 728                 *flags |= FLAGS_DID_CORE_STYLE;
 729         }
 730
 731         switch (os_style) {
 732         case OS_STYLE_NETBSD:
 733                 if (xnh_type == NT_NETBSD_CORE_PROCINFO) {
 734                         uint32_t signo;
 735                         /*
 736                          * Extract the program name.  It is at
 737                          * offset 0x7c, and is up to 32-bytes,
 738                          * including the terminating NUL.
 739                          */
 740                         if (file_printf(ms, ", from '%.31s'",
 741                             &nbuf[doff + 0x7c]) == -1)
 742                                 return size;
 743
 744                         /*
 745                          * Extract the signal number.  It is at
 746                          * offset 0x08.
 747                          */
 748                         (void)memcpy(&signo, &nbuf[doff + 0x08],
 749                             sizeof(signo));
 750                         if (file_printf(ms, " (signal %u)",
 751                             elf_getu32(swap, signo)) == -1)
 752                                 return size;
 753                         *flags |= FLAGS_DID_CORE;
 754                         return size;
 755                 }
 756                 break;
 757
 758         default:
 759                 if (xnh_type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) {
 760                         size_t i, j;
 761                         unsigned char c;
 762                         /*
 763                          * Extract the program name.  We assume
 764                          * it to be 16 characters (that's what it
 765                          * is in SunOS 5.x and Linux).
 766                          *
 767                          * Unfortunately, it's at a different offset
 768                          * in various OSes, so try multiple offsets.
 769                          * If the characters aren't all printable,
 770                          * reject it.
 771                          */
 772                         for (i = 0; i < NOFFSETS; i++) {
 773                                 unsigned char *cname, *cp;
 774                                 size_t reloffset = prpsoffsets(i);
 775                                 size_t noffset = doff + reloffset;
 776                                 size_t k;
 777                                 for (j = 0; j < 16; j++, noffset++,
 778                                     reloffset++) {
 779                                         /*
 780                                          * Make sure we're not past
 781                                          * the end of the buffer; if
 782                                          * we are, just give up.
 783                                          */
 784                                         if (noffset >= size)
 785                                                 goto tryanother;
 786
 787                                         /*
 788                                          * Make sure we're not past
 789                                          * the end of the contents;
 790                                          * if we are, this obviously
 791                                          * isn't the right offset.
 792                                          */
 793                                         if (reloffset >= descsz)
 794                                                 goto tryanother;
 795
 796                                         c = nbuf[noffset];
 797                                         if (c == '\0') {
 798                                                 /*
 799                                                  * A '\0' at the
 800                                                  * beginning is
 801                                                  * obviously wrong.
 802                                                  * Any other '\0'
 803                                                  * means we're done.
 804                                                  */
 805                                                 if (j == 0)
 806                                                         goto tryanother;
 807                                                 else
 808                                                         break;
 809                                         } else {
 810                                                 /*
 811                                                  * A nonprintable
 812                                                  * character is also
 813                                                  * wrong.
 814                                                  */
 815                                                 if (!isprint(c) || isquote(c))
 816                                                         goto tryanother;
 817                                         }
 818                                 }
 819                                 /*
 820                                  * Well, that worked.
 821                                  */
 822
 823                                 /*
 824                                  * Try next offsets, in case this match is
 825                                  * in the middle of a string.
 826                                  */
 827                                 for (k = i + 1 ; k < NOFFSETS ; k++) {
 828                                         size_t no;
 829                                         int adjust = 1;
 830                                         if (prpsoffsets(k) >= prpsoffsets(i))
 831                                                 continue;
 832                                         for (no = doff + prpsoffsets(k);
 833                                              no < doff + prpsoffsets(i); no++)
 834                                                 adjust = adjust
 835                                                          && isprint(nbuf[no]);
 836                                         if (adjust)
 837                                                 i = k;
 838                                 }
 839
 840                                 cname = (unsigned char *)
 841                                     &nbuf[doff + prpsoffsets(i)];
 842                                 for (cp = cname; *cp && isprint(*cp); cp++)
 843                                         continue;
 844                                 /*
 845                                  * Linux apparently appends a space at the end
 846                                  * of the command line: remove it.
 847                                  */
 848                                 while (cp > cname && isspace(cp[-1]))
 849                                         cp--;
 850                                 if (file_printf(ms, ", from '%.*s'",
 851                                     (int)(cp - cname), cname) == -1)
 852                                         return size;
 853                                 *flags |= FLAGS_DID_CORE;
 854                                 return size;
 855
 856                         tryanother:
 857                                 ;
 858                         }
 859                 }
 860                 break;
 861         }
 862 #endif
 863         return offset;
 864 }
 865
 866 /* SunOS 5.x hardware capability descriptions */
 867 typedef struct cap_desc {
 868         uint64_t cd_mask;
 869         const char *cd_name;
 870 } cap_desc_t;
 871
 872 static const cap_desc_t cap_desc_sparc[] = {
 873         { AV_SPARC_MUL32,               "MUL32" },
 874         { AV_SPARC_DIV32,               "DIV32" },
 875         { AV_SPARC_FSMULD,              "FSMULD" },
 876         { AV_SPARC_V8PLUS,              "V8PLUS" },
 877         { AV_SPARC_POPC,                "POPC" },
 878         { AV_SPARC_VIS,                 "VIS" },
 879         { AV_SPARC_VIS2,                "VIS2" },
 880         { AV_SPARC_ASI_BLK_INIT,        "ASI_BLK_INIT" },
 881         { AV_SPARC_FMAF,                "FMAF" },
 882         { AV_SPARC_FJFMAU,              "FJFMAU" },
 883         { AV_SPARC_IMA,                 "IMA" },
 884         { 0, NULL }
 885 };
 886
 887 static const cap_desc_t cap_desc_386[] = {
 888         { AV_386_FPU,                   "FPU" },
 889         { AV_386_TSC,                   "TSC" },
 890         { AV_386_CX8,                   "CX8" },
 891         { AV_386_SEP,                   "SEP" },
 892         { AV_386_AMD_SYSC,              "AMD_SYSC" },
 893         { AV_386_CMOV,                  "CMOV" },
 894         { AV_386_MMX,                   "MMX" },
 895         { AV_386_AMD_MMX,               "AMD_MMX" },
 896         { AV_386_AMD_3DNow,             "AMD_3DNow" },
 897         { AV_386_AMD_3DNowx,            "AMD_3DNowx" },
 898         { AV_386_FXSR,                  "FXSR" },
 899         { AV_386_SSE,                   "SSE" },
 900         { AV_386_SSE2,                  "SSE2" },
 901         { AV_386_PAUSE,                 "PAUSE" },
 902         { AV_386_SSE3,                  "SSE3" },
 903         { AV_386_MON,                   "MON" },
 904         { AV_386_CX16,                  "CX16" },
 905         { AV_386_AHF,                   "AHF" },
 906         { AV_386_TSCP,                  "TSCP" },
 907         { AV_386_AMD_SSE4A,             "AMD_SSE4A" },
 908         { AV_386_POPCNT,                "POPCNT" },
 909         { AV_386_AMD_LZCNT,             "AMD_LZCNT" },
 910         { AV_386_SSSE3,                 "SSSE3" },
 911         { AV_386_SSE4_1,                "SSE4.1" },
 912         { AV_386_SSE4_2,                "SSE4.2" },
 913         { 0, NULL }
 914 };
 915
 916 private int
 917 doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
 918     size_t size, off_t fsize, int *flags, int mach, int strtab)
 919 {
 920         Elf32_Shdr sh32;
 921         Elf64_Shdr sh64;
 922         int stripped = 1;
 923         size_t nbadcap = 0;
 924         void *nbuf;
 925         off_t noff, coff, name_off;
 926         uint64_t cap_hw1 = 0;   /* SunOS 5.x hardware capabilites */
 927         uint64_t cap_sf1 = 0;   /* SunOS 5.x software capabilites */
 928         char name[50];
 929
 930         if (size != xsh_sizeof) {
 931                 if (file_printf(ms, ", corrupted section header size") == -1)
 932                         return -1;
 933                 return 0;
 934         }
 935
 936         /* Read offset of name section to be able to read section names later */
 937         if (pread(fd, xsh_addr, xsh_sizeof, off + size * strtab) == -1) {
 938                 file_badread(ms);
 939                 return -1;
 940         }
 941         name_off = xsh_offset;
 942
 943         for ( ; num; num--) {
 944                 /* Read the name of this section. */
 945                 if (pread(fd, name, sizeof(name), name_off + xsh_name) == -1) {
 946                         file_badread(ms);
 947                         return -1;
 948                 }
 949                 name[sizeof(name) - 1] = '\0';
 950                 if (strcmp(name, ".debug_info") == 0)
 951                         stripped = 0;
 952
 953                 if (pread(fd, xsh_addr, xsh_sizeof, off) == -1) {
 954                         file_badread(ms);
 955                         return -1;
 956                 }
 957                 off += size;
 958
 959                 /* Things we can determine before we seek */
 960                 switch (xsh_type) {
 961                 case SHT_SYMTAB:
 962 #if 0
 963                 case SHT_DYNSYM:
 964 #endif
 965                         stripped = 0;
 966                         break;
 967                 default:
 968                         if (fsize != SIZE_UNKNOWN && xsh_offset > fsize) {
 969                                 /* Perhaps warn here */
 970                                 continue;
 971                         }
 972                         break;
 973                 }
 974
 975                 /* Things we can determine when we seek */
 976                 switch (xsh_type) {
 977                 case SHT_NOTE:
 978                         if ((nbuf = malloc(xsh_size)) == NULL) {
 979                                 file_error(ms, errno, "Cannot allocate memory"
 980                                     " for note");
 981                                 return -1;
 982                         }
 983                         if (pread(fd, nbuf, xsh_size, xsh_offset) == -1) {
 984                                 file_badread(ms);
 985                                 free(nbuf);
 986                                 return -1;
 987                         }
 988
 989                         noff = 0;
 990                         for (;;) {
 991                                 if (noff >= (off_t)xsh_size)
 992                                         break;
 993                                 noff = donote(ms, nbuf, (size_t)noff,
 994                                     xsh_size, clazz, swap, 4, flags);
 995                                 if (noff == 0)
 996                                         break;
 997                         }
 998                         free(nbuf);
 999                         break;
1000                 case SHT_SUNW_cap:
1001                         switch (mach) {
1002                         case EM_SPARC:
1003                         case EM_SPARCV9:
1004                         case EM_IA_64:
1005                         case EM_386:
1006                         case EM_AMD64:
1007                                 break;
1008                         default:
1009                                 goto skip;
1010                         }
1011
1012                         if (nbadcap > 5)
1013                                 break;
1014                         if (lseek(fd, xsh_offset, SEEK_SET) == (off_t)-1) {
1015                                 file_badseek(ms);
1016                                 return -1;
1017                         }
1018                         coff = 0;
1019                         for (;;) {
1020                                 Elf32_Cap cap32;
1021                                 Elf64_Cap cap64;
1022                                 char cbuf[/*CONSTCOND*/
1023                                     MAX(sizeof cap32, sizeof cap64)];
1024                                 if ((coff += xcap_sizeof) > (off_t)xsh_size)
1025                                         break;
1026                                 if (read(fd, cbuf, (size_t)xcap_sizeof) !=
1027                                     (ssize_t)xcap_sizeof) {
1028                                         file_badread(ms);
1029                                         return -1;
1030                                 }
1031                                 if (cbuf[0] == 'A') {
1032 #ifdef notyet
1033                                         char *p = cbuf + 1;
1034                                         uint32_t len, tag;
1035                                         memcpy(&len, p, sizeof(len));
1036                                         p += 4;
1037                                         len = getu32(swap, len);
1038                                         if (memcmp("gnu", p, 3) != 0) {
1039                                             if (file_printf(ms,
1040                                                 ", unknown capability %.3s", p)
1041                                                 == -1)
1042                                                 return -1;
1043                                             break;
1044                                         }
1045                                         p += strlen(p) + 1;
1046                                         tag = *p++;
1047                                         memcpy(&len, p, sizeof(len));
1048                                         p += 4;
1049                                         len = getu32(swap, len);
1050                                         if (tag != 1) {
1051                                             if (file_printf(ms, ", unknown gnu"
1052                                                 " capability tag %d", tag)
1053                                                 == -1)
1054                                                 return -1;
1055                                             break;
1056                                         }
1057                                         // gnu attributes
1058 #endif
1059                                         break;
1060                                 }
1061                                 (void)memcpy(xcap_addr, cbuf, xcap_sizeof);
1062                                 switch (xcap_tag) {
1063                                 case CA_SUNW_NULL:
1064                                         break;
1065                                 case CA_SUNW_HW_1:
1066                                         cap_hw1 |= xcap_val;
1067                                         break;
1068                                 case CA_SUNW_SF_1:
1069                                         cap_sf1 |= xcap_val;
1070                                         break;
1071                                 default:
1072                                         if (file_printf(ms,
1073                                             ", with unknown capability "
1074                                             "0x%" INT64_T_FORMAT "x = 0x%"
1075                                             INT64_T_FORMAT "x",
1076                                             (unsigned long long)xcap_tag,
1077                                             (unsigned long long)xcap_val) == -1)
1078                                                 return -1;
1079                                         if (nbadcap++ > 2)
1080                                                 coff = xsh_size;
1081                                         break;
1082                                 }
1083                         }
1084                         /*FALLTHROUGH*/
1085                 skip:
1086                 default:
1087                         break;
1088                 }
1089         }
1090
1091         if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1)
1092                 return -1;
1093         if (cap_hw1) {
1094                 const cap_desc_t *cdp;
1095                 switch (mach) {
1096                 case EM_SPARC:
1097                 case EM_SPARC32PLUS:
1098                 case EM_SPARCV9:
1099                         cdp = cap_desc_sparc;
1100                         break;
1101                 case EM_386:
1102                 case EM_IA_64:
1103                 case EM_AMD64:
1104                         cdp = cap_desc_386;
1105                         break;
1106                 default:
1107                         cdp = NULL;
1108                         break;
1109                 }
1110                 if (file_printf(ms, ", uses") == -1)
1111                         return -1;
1112                 if (cdp) {
1113                         while (cdp->cd_name) {
1114                                 if (cap_hw1 & cdp->cd_mask) {
1115                                         if (file_printf(ms,
1116                                             " %s", cdp->cd_name) == -1)
1117                                                 return -1;
1118                                         cap_hw1 &= ~cdp->cd_mask;
1119                                 }
1120                                 ++cdp;
1121                         }
1122                         if (cap_hw1)
1123                                 if (file_printf(ms,
1124                                     " unknown hardware capability 0x%"
1125                                     INT64_T_FORMAT "x",
1126                                     (unsigned long long)cap_hw1) == -1)
1127                                         return -1;
1128                 } else {
1129                         if (file_printf(ms,
1130                             " hardware capability 0x%" INT64_T_FORMAT "x",
1131                             (unsigned long long)cap_hw1) == -1)
1132                                 return -1;
1133                 }
1134         }
1135         if (cap_sf1) {
1136                 if (cap_sf1 & SF1_SUNW_FPUSED) {
1137                         if (file_printf(ms,
1138                             (cap_sf1 & SF1_SUNW_FPKNWN)
1139                             ? ", uses frame pointer"
1140                             : ", not known to use frame pointer") == -1)
1141                                 return -1;
1142                 }
1143                 cap_sf1 &= ~SF1_SUNW_MASK;
1144                 if (cap_sf1)
1145                         if (file_printf(ms,
1146                             ", with unknown software capability 0x%"
1147                             INT64_T_FORMAT "x",
1148                             (unsigned long long)cap_sf1) == -1)
1149                                 return -1;
1150         }
1151         return 0;
1152 }
1153
1154 /*
1155  * Look through the program headers of an executable image, searching
1156  * for a PT_INTERP section; if one is found, it's dynamically linked,
1157  * otherwise it's statically linked.
1158  */
1159 private int
1160 dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
1161     int num, size_t size, off_t fsize, int *flags, int sh_num)
1162 {
1163         Elf32_Phdr ph32;
1164         Elf64_Phdr ph64;
1165         const char *linking_style = "statically";
1166         const char *shared_libraries = "";
1167         unsigned char nbuf[BUFSIZ];
1168         ssize_t bufsize;
1169         size_t offset, align, len;
1170
1171         if (size != xph_sizeof) {
1172                 if (file_printf(ms, ", corrupted program header size") == -1)
1173                         return -1;
1174                 return 0;
1175         }
1176
1177         for ( ; num; num--) {
1178                 if (pread(fd, xph_addr, xph_sizeof, off) == -1) {
1179                         file_badread(ms);
1180                         return -1;
1181                 }
1182
1183                 off += size;
1184
1185                 /* Things we can determine before we seek */
1186                 switch (xph_type) {
1187                 case PT_DYNAMIC:
1188                         linking_style = "dynamically";
1189                         break;
1190                 case PT_INTERP:
1191                         shared_libraries = " (uses shared libs)";
1192                         break;
1193                 default:
1194                         if (fsize != SIZE_UNKNOWN && xph_offset > fsize) {
1195                                 /* Maybe warn here? */
1196                                 continue;
1197                         }
1198                         break;
1199                 }
1200
1201                 /* Things we can determine when we seek */
1202                 switch (xph_type) {
1203                 case PT_NOTE:
1204                         if (((align = xph_align) & 0x80000000UL) != 0 ||
1205                             align < 4) {
1206                                 if (file_printf(ms,
1207                                     ", invalid note alignment 0x%lx",
1208                                     (unsigned long)align) == -1)
1209                                         return -1;
1210                                 align = 4;
1211                         }
1212                         if (sh_num)
1213                                 break;
1214                         /*
1215                          * This is a PT_NOTE section; loop through all the notes
1216                          * in the section.
1217                          */
1218                         len = xph_filesz < sizeof(nbuf) ? xph_filesz
1219                             : sizeof(nbuf);
1220                         bufsize = pread(fd, nbuf, len, xph_offset);
1221                         if (bufsize == -1) {
1222                                 file_badread(ms);
1223                                 return -1;
1224                         }
1225                         offset = 0;
1226                         for (;;) {
1227                                 if (offset >= (size_t)bufsize)
1228                                         break;
1229                                 offset = donote(ms, nbuf, offset,
1230                                     (size_t)bufsize, clazz, swap, align,
1231                                     flags);
1232                                 if (offset == 0)
1233                                         break;
1234                         }
1235                         break;
1236                 default:
1237                         break;
1238                 }
1239         }
1240         if (file_printf(ms, ", %s linked%s", linking_style, shared_libraries)
1241             == -1)
1242             return -1;
1243         return 0;
1244 }
1245
1246
1247 protected int
1248 file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
1249     size_t nbytes)
1250 {
1251         union {
1252                 int32_t l;
1253                 char c[sizeof (int32_t)];
1254         } u;
1255         int clazz;
1256         int swap;
1257         struct stat st;
1258         off_t fsize;
1259         int flags = 0;
1260         Elf32_Ehdr elf32hdr;
1261         Elf64_Ehdr elf64hdr;
1262         uint16_t type, phnum, shnum;
1263
1264         if (ms->flags & (MAGIC_MIME|MAGIC_APPLE))
1265                 return 0;
1266         /*
1267          * ELF executables have multiple section headers in arbitrary
1268          * file locations and thus file(1) cannot determine it from easily.
1269          * Instead we traverse thru all section headers until a symbol table
1270          * one is found or else the binary is stripped.
1271          * Return immediately if it's not ELF (so we avoid pipe2file unless needed).
1272          */
1273         if (buf[EI_MAG0] != ELFMAG0
1274             || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
1275             || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
1276                 return 0;
1277
1278         /*
1279          * If we cannot seek, it must be a pipe, socket or fifo.
1280          */
1281         if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE))
1282                 fd = file_pipe2file(ms, fd, buf, nbytes);
1283
1284         if (fstat(fd, &st) == -1) {
1285                 file_badread(ms);
1286                 return -1;
1287         }
1288         if (S_ISREG(st.st_mode) || st.st_size != 0)
1289                 fsize = st.st_size;
1290         else
1291                 fsize = SIZE_UNKNOWN;
1292
1293         clazz = buf[EI_CLASS];
1294
1295         switch (clazz) {
1296         case ELFCLASS32:
1297 #undef elf_getu
1298 #define elf_getu(a, b)  elf_getu32(a, b)
1299 #undef elfhdr
1300 #define elfhdr elf32hdr
1301 #include "elfclass.h"
1302         case ELFCLASS64:
1303 #undef elf_getu
1304 #define elf_getu(a, b)  elf_getu64(a, b)
1305 #undef elfhdr
1306 #define elfhdr elf64hdr
1307 #include "elfclass.h"
1308         default:
1309             if (file_printf(ms, ", unknown class %d", clazz) == -1)
1310                     return -1;
1311             break;
1312         }
1313         return 0;
1314 }
1315 #endif