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 1.86 2010/07/21 16:47:18 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, int *,
  51     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 private uint16_t
  64 getu16(int swap, uint16_t value)
  65 {
  66         union {
  67                 uint16_t ui;
  68                 char c[2];
  69         } retval, tmpval;
  70
  71         if (swap) {
  72                 tmpval.ui = value;
  73
  74                 retval.c[0] = tmpval.c[1];
  75                 retval.c[1] = tmpval.c[0];
  76
  77                 return retval.ui;
  78         } else
  79                 return value;
  80 }
  81
  82 private uint32_t
  83 getu32(int swap, uint32_t value)
  84 {
  85         union {
  86                 uint32_t ui;
  87                 char c[4];
  88         } retval, tmpval;
  89
  90         if (swap) {
  91                 tmpval.ui = value;
  92
  93                 retval.c[0] = tmpval.c[3];
  94                 retval.c[1] = tmpval.c[2];
  95                 retval.c[2] = tmpval.c[1];
  96                 retval.c[3] = tmpval.c[0];
  97
  98                 return retval.ui;
  99         } else
 100                 return value;
 101 }
 102
 103 private uint64_t
 104 getu64(int swap, uint64_t value)
 105 {
 106         union {
 107                 uint64_t ui;
 108                 char c[8];
 109         } retval, tmpval;
 110
 111         if (swap) {
 112                 tmpval.ui = value;
 113
 114                 retval.c[0] = tmpval.c[7];
 115                 retval.c[1] = tmpval.c[6];
 116                 retval.c[2] = tmpval.c[5];
 117                 retval.c[3] = tmpval.c[4];
 118                 retval.c[4] = tmpval.c[3];
 119                 retval.c[5] = tmpval.c[2];
 120                 retval.c[6] = tmpval.c[1];
 121                 retval.c[7] = tmpval.c[0];
 122
 123                 return retval.ui;
 124         } else
 125                 return value;
 126 }
 127
 128 #define elf_getu16(swap, value) getu16(swap, value)
 129 #define elf_getu32(swap, value) getu32(swap, value)
 130 #ifdef USE_ARRAY_FOR_64BIT_TYPES
 131 # define elf_getu64(swap, array) \
 132         ((swap ? ((uint64_t)elf_getu32(swap, array[0])) << 32 : elf_getu32(swap, array[0])) + \
 133          (swap ? elf_getu32(swap, array[1]) : ((uint64_t)elf_getu32(swap, array[1]) << 32)))
 134 #else
 135 # define elf_getu64(swap, value) getu64(swap, value)
 136 #endif
 137
 138 #define xsh_addr        (clazz == ELFCLASS32                    \
 139                          ? (void *) &sh32                       \
 140                          : (void *) &sh64)
 141 #define xsh_sizeof      (clazz == ELFCLASS32                    \
 142                          ? sizeof sh32                          \
 143                          : sizeof sh64)
 144 #define xsh_size        (clazz == ELFCLASS32                    \
 145                          ? elf_getu32(swap, sh32.sh_size)       \
 146                          : elf_getu64(swap, sh64.sh_size))
 147 #define xsh_offset      (clazz == ELFCLASS32                    \
 148                          ? elf_getu32(swap, sh32.sh_offset)     \
 149                          : elf_getu64(swap, sh64.sh_offset))
 150 #define xsh_type        (clazz == ELFCLASS32                    \
 151                          ? elf_getu32(swap, sh32.sh_type)       \
 152                          : elf_getu32(swap, sh64.sh_type))
 153 #define xph_addr        (clazz == ELFCLASS32                    \
 154                          ? (void *) &ph32                       \
 155                          : (void *) &ph64)
 156 #define xph_sizeof      (clazz == ELFCLASS32                    \
 157                          ? sizeof ph32                          \
 158                          : sizeof ph64)
 159 #define xph_type        (clazz == ELFCLASS32                    \
 160                          ? elf_getu32(swap, ph32.p_type)        \
 161                          : elf_getu32(swap, ph64.p_type))
 162 #define xph_offset      (off_t)(clazz == ELFCLASS32             \
 163                          ? elf_getu32(swap, ph32.p_offset)      \
 164                          : elf_getu64(swap, ph64.p_offset))
 165 #define xph_align       (size_t)((clazz == ELFCLASS32           \
 166                          ? (off_t) (ph32.p_align ?              \
 167                             elf_getu32(swap, ph32.p_align) : 4) \
 168                          : (off_t) (ph64.p_align ?              \
 169                             elf_getu64(swap, ph64.p_align) : 4)))
 170 #define xph_filesz      (size_t)((clazz == ELFCLASS32           \
 171                          ? elf_getu32(swap, ph32.p_filesz)      \
 172                          : elf_getu64(swap, ph64.p_filesz)))
 173 #define xnh_addr        (clazz == ELFCLASS32                    \
 174                          ? (void *) &nh32                       \
 175                          : (void *) &nh64)
 176 #define xph_memsz       (size_t)((clazz == ELFCLASS32           \
 177                          ? elf_getu32(swap, ph32.p_memsz)       \
 178                          : elf_getu64(swap, ph64.p_memsz)))
 179 #define xnh_sizeof      (clazz == ELFCLASS32                    \
 180                          ? sizeof nh32                          \
 181                          : sizeof nh64)
 182 #define xnh_type        (clazz == ELFCLASS32                    \
 183                          ? elf_getu32(swap, nh32.n_type)        \
 184                          : elf_getu32(swap, nh64.n_type))
 185 #define xnh_namesz      (clazz == ELFCLASS32                    \
 186                          ? elf_getu32(swap, nh32.n_namesz)      \
 187                          : elf_getu32(swap, nh64.n_namesz))
 188 #define xnh_descsz      (clazz == ELFCLASS32                    \
 189                          ? elf_getu32(swap, nh32.n_descsz)      \
 190                          : elf_getu32(swap, nh64.n_descsz))
 191 #define prpsoffsets(i)  (clazz == ELFCLASS32                    \
 192                          ? prpsoffsets32[i]                     \
 193                          : prpsoffsets64[i])
 194 #define xcap_addr       (clazz == ELFCLASS32                    \
 195                          ? (void *) &cap32                      \
 196                          : (void *) &cap64)
 197 #define xcap_sizeof     (clazz == ELFCLASS32                    \
 198                          ? sizeof cap32                         \
 199                          : sizeof cap64)
 200 #define xcap_tag        (clazz == ELFCLASS32                    \
 201                          ? elf_getu32(swap, cap32.c_tag)        \
 202                          : elf_getu64(swap, cap64.c_tag))
 203 #define xcap_val        (clazz == ELFCLASS32                    \
 204                          ? elf_getu32(swap, cap32.c_un.c_val)   \
 205                          : elf_getu64(swap, cap64.c_un.c_val))
 206
 207 #ifdef ELFCORE
 208 /*
 209  * Try larger offsets first to avoid false matches
 210  * from earlier data that happen to look like strings.
 211  */
 212 static const size_t     prpsoffsets32[] = {
 213 #ifdef USE_NT_PSINFO
 214         104,            /* SunOS 5.x (command line) */
 215         88,             /* SunOS 5.x (short name) */
 216 #endif /* USE_NT_PSINFO */
 217
 218         100,            /* SunOS 5.x (command line) */
 219         84,             /* SunOS 5.x (short name) */
 220
 221         44,             /* Linux (command line) */
 222         28,             /* Linux 2.0.36 (short name) */
 223
 224         8,              /* FreeBSD */
 225 };
 226
 227 static const size_t     prpsoffsets64[] = {
 228 #ifdef USE_NT_PSINFO
 229         152,            /* SunOS 5.x (command line) */
 230         136,            /* SunOS 5.x (short name) */
 231 #endif /* USE_NT_PSINFO */
 232
 233         136,            /* SunOS 5.x, 64-bit (command line) */
 234         120,            /* SunOS 5.x, 64-bit (short name) */
 235
 236         56,             /* Linux (command line) */
 237         40,             /* Linux (tested on core from 2.4.x, short name) */
 238
 239         16,             /* FreeBSD, 64-bit */
 240 };
 241
 242 #define NOFFSETS32      (sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
 243 #define NOFFSETS64      (sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
 244
 245 #define NOFFSETS        (clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
 246
 247 /*
 248  * Look through the program headers of an executable image, searching
 249  * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
 250  * "FreeBSD"; if one is found, try looking in various places in its
 251  * contents for a 16-character string containing only printable
 252  * characters - if found, that string should be the name of the program
 253  * that dropped core.  Note: right after that 16-character string is,
 254  * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
 255  * Linux, a longer string (80 characters, in 5.x, probably other
 256  * SVR4-flavored systems, and Linux) containing the start of the
 257  * command line for that program.
 258  *
 259  * SunOS 5.x core files contain two PT_NOTE sections, with the types
 260  * NT_PRPSINFO (old) and NT_PSINFO (new).  These structs contain the
 261  * same info about the command name and command line, so it probably
 262  * isn't worthwhile to look for NT_PSINFO, but the offsets are provided
 263  * above (see USE_NT_PSINFO), in case we ever decide to do so.  The
 264  * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent;
 265  * the SunOS 5.x file command relies on this (and prefers the latter).
 266  *
 267  * The signal number probably appears in a section of type NT_PRSTATUS,
 268  * but that's also rather OS-dependent, in ways that are harder to
 269  * dissect with heuristics, so I'm not bothering with the signal number.
 270  * (I suppose the signal number could be of interest in situations where
 271  * you don't have the binary of the program that dropped core; if you
 272  * *do* have that binary, the debugger will probably tell you what
 273  * signal it was.)
 274  */
 275
 276 #define OS_STYLE_SVR4           0
 277 #define OS_STYLE_FREEBSD        1
 278 #define OS_STYLE_NETBSD         2
 279
 280 private const char os_style_names[][8] = {
 281         "SVR4",
 282         "FreeBSD",
 283         "NetBSD",
 284 };
 285
 286 #define FLAGS_DID_CORE          1
 287 #define FLAGS_DID_NOTE          2
 288 #define FLAGS_DID_CORE_STYLE    4
 289 #define FLAGS_IS_CORE           8
 290
 291 private int
 292 dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
 293     int num, size_t size, off_t fsize, int *flags)
 294 {
 295         Elf32_Phdr ph32;
 296         Elf64_Phdr ph64;
 297         size_t offset;
 298         unsigned char nbuf[BUFSIZ];
 299         ssize_t bufsize;
 300         off_t savedoffset;
 301         struct stat st;
 302
 303         if (fstat(fd, &st) < 0) {
 304                 file_badread(ms);
 305                 return -1;
 306         }
 307
 308         if (size != xph_sizeof) {
 309                 if (file_printf(ms, ", corrupted program header size") == -1)
 310                         return -1;
 311                 return 0;
 312         }
 313
 314         /*
 315          * Loop through all the program headers.
 316          */
 317         for ( ; num; num--) {
 318                 if ((savedoffset = lseek(fd, off, SEEK_SET)) == (off_t)-1) {
 319                         file_badseek(ms);
 320                         return -1;
 321                 }
 322                 if (read(fd, xph_addr, xph_sizeof) == -1) {
 323                         file_badread(ms);
 324                         return -1;
 325                 }
 326                 if (xph_offset > fsize) {
 327                         if (lseek(fd, savedoffset, SEEK_SET) == (off_t)-1) {
 328                                 file_badseek(ms);
 329                                 return -1;
 330                         }
 331                         continue;
 332                 }
 333
 334                 off += size;
 335                 if (xph_type != PT_NOTE)
 336                         continue;
 337
 338                 /*
 339                  * This is a PT_NOTE section; loop through all the notes
 340                  * in the section.
 341                  */
 342                 if (lseek(fd, xph_offset, SEEK_SET) == (off_t)-1) {
 343                         file_badseek(ms);
 344                         return -1;
 345                 }
 346                 bufsize = read(fd, nbuf,
 347                     ((xph_filesz < sizeof(nbuf)) ? xph_filesz : sizeof(nbuf)));
 348                 if (bufsize == -1) {
 349                         file_badread(ms);
 350                         return -1;
 351                 }
 352                 offset = 0;
 353                 for (;;) {
 354                         if (offset >= (size_t)bufsize)
 355                                 break;
 356                         offset = donote(ms, nbuf, offset, (size_t)bufsize,
 357                             clazz, swap, 4, flags);
 358                         if (offset == 0)
 359                                 break;
 360
 361                 }
 362         }
 363         return 0;
 364 }
 365 #endif
 366
 367 private size_t
 368 donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
 369     int clazz, int swap, size_t align, int *flags)
 370 {
 371         Elf32_Nhdr nh32;
 372         Elf64_Nhdr nh64;
 373         size_t noff, doff;
 374 #ifdef ELFCORE
 375         int os_style = -1;
 376 #endif
 377         uint32_t namesz, descsz;
 378         unsigned char *nbuf = CAST(unsigned char *, vbuf);
 379
 380         (void)memcpy(xnh_addr, &nbuf[offset], xnh_sizeof);
 381         offset += xnh_sizeof;
 382
 383         namesz = xnh_namesz;
 384         descsz = xnh_descsz;
 385         if ((namesz == 0) && (descsz == 0)) {
 386                 /*
 387                  * We're out of note headers.
 388                  */
 389                 return (offset >= size) ? offset : size;
 390         }
 391
 392         if (namesz & 0x80000000) {
 393             (void)file_printf(ms, ", bad note name size 0x%lx",
 394                 (unsigned long)namesz);
 395             return offset;
 396         }
 397
 398         if (descsz & 0x80000000) {
 399             (void)file_printf(ms, ", bad note description size 0x%lx",
 400                 (unsigned long)descsz);
 401             return offset;
 402         }
 403
 404
 405         noff = offset;
 406         doff = ELF_ALIGN(offset + namesz);
 407
 408         if (offset + namesz > size) {
 409                 /*
 410                  * We're past the end of the buffer.
 411                  */
 412                 return doff;
 413         }
 414
 415         offset = ELF_ALIGN(doff + descsz);
 416         if (doff + descsz > size) {
 417                 /*
 418                  * We're past the end of the buffer.
 419                  */
 420                 return (offset >= size) ? offset : size;
 421         }
 422
 423         if (*flags & FLAGS_DID_NOTE)
 424                 goto core;
 425
 426         if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
 427             xnh_type == NT_GNU_VERSION && descsz == 16) {
 428                 uint32_t desc[4];
 429                 (void)memcpy(desc, &nbuf[doff], sizeof(desc));
 430
 431                 if (file_printf(ms, ", for GNU/") == -1)
 432                         return size;
 433                 switch (elf_getu32(swap, desc[0])) {
 434                 case GNU_OS_LINUX:
 435                         if (file_printf(ms, "Linux") == -1)
 436                                 return size;
 437                         break;
 438                 case GNU_OS_HURD:
 439                         if (file_printf(ms, "Hurd") == -1)
 440                                 return size;
 441                         break;
 442                 case GNU_OS_SOLARIS:
 443                         if (file_printf(ms, "Solaris") == -1)
 444                                 return size;
 445                         break;
 446                 case GNU_OS_KFREEBSD:
 447                         if (file_printf(ms, "kFreeBSD") == -1)
 448                                 return size;
 449                         break;
 450                 case GNU_OS_KNETBSD:
 451                         if (file_printf(ms, "kNetBSD") == -1)
 452                                 return size;
 453                         break;
 454                 default:
 455                         if (file_printf(ms, "<unknown>") == -1)
 456                                 return size;
 457                 }
 458                 if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]),
 459                     elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1)
 460                         return size;
 461                 *flags |= FLAGS_DID_NOTE;
 462                 return size;
 463         }
 464
 465         if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0 &&
 466             xnh_type == NT_NETBSD_VERSION && descsz == 4) {
 467                 uint32_t desc;
 468                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 469                 desc = elf_getu32(swap, desc);
 470
 471                 if (file_printf(ms, ", for NetBSD") == -1)
 472                         return size;
 473                 /*
 474                  * The version number used to be stuck as 199905, and was thus
 475                  * basically content-free.  Newer versions of NetBSD have fixed
 476                  * this and now use the encoding of __NetBSD_Version__:
 477                  *
 478                  *      MMmmrrpp00
 479                  *
 480                  * M = major version
 481                  * m = minor version
 482                  * r = release ["",A-Z,Z[A-Z] but numeric]
 483                  * p = patchlevel
 484                  */
 485                 if (desc > 100000000U) {
 486                         uint32_t ver_patch = (desc / 100) % 100;
 487                         uint32_t ver_rel = (desc / 10000) % 100;
 488                         uint32_t ver_min = (desc / 1000000) % 100;
 489                         uint32_t ver_maj = desc / 100000000;
 490
 491                         if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1)
 492                                 return size;
 493                         if (ver_rel == 0 && ver_patch != 0) {
 494                                 if (file_printf(ms, ".%u", ver_patch) == -1)
 495                                         return size;
 496                         } else if (ver_rel != 0) {
 497                                 while (ver_rel > 26) {
 498                                         if (file_printf(ms, "Z") == -1)
 499                                                 return size;
 500                                         ver_rel -= 26;
 501                                 }
 502                                 if (file_printf(ms, "%c", 'A' + ver_rel - 1)
 503                                     == -1)
 504                                         return size;
 505                         }
 506                 }
 507                 *flags |= FLAGS_DID_NOTE;
 508                 return size;
 509         }
 510
 511         if (namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0 &&
 512             xnh_type == NT_FREEBSD_VERSION && descsz == 4) {
 513                 uint32_t desc;
 514                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 515                 desc = elf_getu32(swap, desc);
 516                 if (file_printf(ms, ", for FreeBSD") == -1)
 517                         return size;
 518
 519                 /*
 520                  * Contents is __FreeBSD_version, whose relation to OS
 521                  * versions is defined by a huge table in the Porter's
 522                  * Handbook.  This is the general scheme:
 523                  *
 524                  * Releases:
 525                  *      Mmp000 (before 4.10)
 526                  *      Mmi0p0 (before 5.0)
 527                  *      Mmm0p0
 528                  *
 529                  * Development branches:
 530                  *      Mmpxxx (before 4.6)
 531                  *      Mmp1xx (before 4.10)
 532                  *      Mmi1xx (before 5.0)
 533                  *      M000xx (pre-M.0)
 534                  *      Mmm1xx
 535                  *
 536                  * M = major version
 537                  * m = minor version
 538                  * i = minor version increment (491000 -> 4.10)
 539                  * p = patchlevel
 540                  * x = revision
 541                  *
 542                  * The first release of FreeBSD to use ELF by default
 543                  * was version 3.0.
 544                  */
 545                 if (desc == 460002) {
 546                         if (file_printf(ms, " 4.6.2") == -1)
 547                                 return size;
 548                 } else if (desc < 460100) {
 549                         if (file_printf(ms, " %d.%d", desc / 100000,
 550                             desc / 10000 % 10) == -1)
 551                                 return size;
 552                         if (desc / 1000 % 10 > 0)
 553                                 if (file_printf(ms, ".%d", desc / 1000 % 10)
 554                                     == -1)
 555                                         return size;
 556                         if ((desc % 1000 > 0) || (desc % 100000 == 0))
 557                                 if (file_printf(ms, " (%d)", desc) == -1)
 558                                         return size;
 559                 } else if (desc < 500000) {
 560                         if (file_printf(ms, " %d.%d", desc / 100000,
 561                             desc / 10000 % 10 + desc / 1000 % 10) == -1)
 562                                 return size;
 563                         if (desc / 100 % 10 > 0) {
 564                                 if (file_printf(ms, " (%d)", desc) == -1)
 565                                         return size;
 566                         } else if (desc / 10 % 10 > 0) {
 567                                 if (file_printf(ms, ".%d", desc / 10 % 10)
 568                                     == -1)
 569                                         return size;
 570                         }
 571                 } else {
 572                         if (file_printf(ms, " %d.%d", desc / 100000,
 573                             desc / 1000 % 100) == -1)
 574                                 return size;
 575                         if ((desc / 100 % 10 > 0) ||
 576                             (desc % 100000 / 100 == 0)) {
 577                                 if (file_printf(ms, " (%d)", desc) == -1)
 578                                         return size;
 579                         } else if (desc / 10 % 10 > 0) {
 580                                 if (file_printf(ms, ".%d", desc / 10 % 10)
 581                                     == -1)
 582                                         return size;
 583                         }
 584                 }
 585                 *flags |= FLAGS_DID_NOTE;
 586                 return size;
 587         }
 588
 589         if (namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 &&
 590             xnh_type == NT_OPENBSD_VERSION && descsz == 4) {
 591                 if (file_printf(ms, ", for OpenBSD") == -1)
 592                         return size;
 593                 /* Content of note is always 0 */
 594                 *flags |= FLAGS_DID_NOTE;
 595                 return size;
 596         }
 597
 598         if (namesz == 10 && strcmp((char *)&nbuf[noff], "DragonFly") == 0 &&
 599             xnh_type == NT_DRAGONFLY_VERSION && descsz == 4) {
 600                 uint32_t desc;
 601                 if (file_printf(ms, ", for DragonFly") == -1)
 602                         return size;
 603                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 604                 desc = elf_getu32(swap, desc);
 605                 if (file_printf(ms, " %d.%d.%d", desc / 100000,
 606                     desc / 10000 % 10, desc % 10000) == -1)
 607                         return size;
 608                 *flags |= FLAGS_DID_NOTE;
 609                 return size;
 610         }
 611
 612 core:
 613         /*
 614          * Sigh.  The 2.0.36 kernel in Debian 2.1, at
 615          * least, doesn't correctly implement name
 616          * sections, in core dumps, as specified by
 617          * the "Program Linking" section of "UNIX(R) System
 618          * V Release 4 Programmer's Guide: ANSI C and
 619          * Programming Support Tools", because my copy
 620          * clearly says "The first 'namesz' bytes in 'name'
 621          * contain a *null-terminated* [emphasis mine]
 622          * character representation of the entry's owner
 623          * or originator", but the 2.0.36 kernel code
 624          * doesn't include the terminating null in the
 625          * name....
 626          */
 627         if ((namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) ||
 628             (namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) {
 629                 os_style = OS_STYLE_SVR4;
 630         }
 631
 632         if ((namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) {
 633                 os_style = OS_STYLE_FREEBSD;
 634         }
 635
 636         if ((namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11)
 637             == 0)) {
 638                 os_style = OS_STYLE_NETBSD;
 639         }
 640
 641 #ifdef ELFCORE
 642         if ((*flags & FLAGS_DID_CORE) != 0)
 643                 return size;
 644
 645         if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) {
 646                 if (file_printf(ms, ", %s-style", os_style_names[os_style])
 647                     == -1)
 648                         return size;
 649                 *flags |= FLAGS_DID_CORE_STYLE;
 650         }
 651
 652         switch (os_style) {
 653         case OS_STYLE_NETBSD:
 654                 if (xnh_type == NT_NETBSD_CORE_PROCINFO) {
 655                         uint32_t signo;
 656                         /*
 657                          * Extract the program name.  It is at
 658                          * offset 0x7c, and is up to 32-bytes,
 659                          * including the terminating NUL.
 660                          */
 661                         if (file_printf(ms, ", from '%.31s'",
 662                             &nbuf[doff + 0x7c]) == -1)
 663                                 return size;
 664
 665                         /*
 666                          * Extract the signal number.  It is at
 667                          * offset 0x08.
 668                          */
 669                         (void)memcpy(&signo, &nbuf[doff + 0x08],
 670                             sizeof(signo));
 671                         if (file_printf(ms, " (signal %u)",
 672                             elf_getu32(swap, signo)) == -1)
 673                                 return size;
 674                         *flags |= FLAGS_DID_CORE;
 675                         return size;
 676                 }
 677                 break;
 678
 679         default:
 680                 if (xnh_type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) {
 681                         size_t i, j;
 682                         unsigned char c;
 683                         /*
 684                          * Extract the program name.  We assume
 685                          * it to be 16 characters (that's what it
 686                          * is in SunOS 5.x and Linux).
 687                          *
 688                          * Unfortunately, it's at a different offset
 689                          * in various OSes, so try multiple offsets.
 690                          * If the characters aren't all printable,
 691                          * reject it.
 692                          */
 693                         for (i = 0; i < NOFFSETS; i++) {
 694                                 unsigned char *cname, *cp;
 695                                 size_t reloffset = prpsoffsets(i);
 696                                 size_t noffset = doff + reloffset;
 697                                 for (j = 0; j < 16; j++, noffset++,
 698                                     reloffset++) {
 699                                         /*
 700                                          * Make sure we're not past
 701                                          * the end of the buffer; if
 702                                          * we are, just give up.
 703                                          */
 704                                         if (noffset >= size)
 705                                                 goto tryanother;
 706
 707                                         /*
 708                                          * Make sure we're not past
 709                                          * the end of the contents;
 710                                          * if we are, this obviously
 711                                          * isn't the right offset.
 712                                          */
 713                                         if (reloffset >= descsz)
 714                                                 goto tryanother;
 715
 716                                         c = nbuf[noffset];
 717                                         if (c == '\0') {
 718                                                 /*
 719                                                  * A '\0' at the
 720                                                  * beginning is
 721                                                  * obviously wrong.
 722                                                  * Any other '\0'
 723                                                  * means we're done.
 724                                                  */
 725                                                 if (j == 0)
 726                                                         goto tryanother;
 727                                                 else
 728                                                         break;
 729                                         } else {
 730                                                 /*
 731                                                  * A nonprintable
 732                                                  * character is also
 733                                                  * wrong.
 734                                                  */
 735                                                 if (!isprint(c) || isquote(c))
 736                                                         goto tryanother;
 737                                         }
 738                                 }
 739                                 /*
 740                                  * Well, that worked.
 741                                  */
 742
 743                                 /*
 744                                  * Try next offsets, in case this match is
 745                                  * in the middle of a string.
 746                                  */
 747                                 size_t k;
 748                                 for (k = i + 1 ; k < NOFFSETS ; k++) {
 749                                         if (prpsoffsets(k) >= prpsoffsets(i))
 750                                                 continue;
 751                                         size_t no;
 752                                         int adjust = 1;
 753                                         for (no = doff + prpsoffsets(k);
 754                                              no < doff + prpsoffsets(i); no++)
 755                                                 adjust = adjust
 756                                                          && isprint(nbuf[no]);
 757                                         if (adjust)
 758                                                 i = k;
 759                                 }
 760
 761                                 cname = (unsigned char *)
 762                                     &nbuf[doff + prpsoffsets(i)];
 763                                 for (cp = cname; *cp && isprint(*cp); cp++)
 764                                         continue;
 765                                 /*
 766                                  * Linux apparently appends a space at the end
 767                                  * of the command line: remove it.
 768                                  */
 769                                 while (cp > cname && isspace(cp[-1]))
 770                                         cp--;
 771                                 if (file_printf(ms, ", from '%.*s'",
 772                                     (int)(cp - cname), cname) == -1)
 773                                         return size;
 774                                 *flags |= FLAGS_DID_CORE;
 775                                 return size;
 776
 777                         tryanother:
 778                                 ;
 779                         }
 780                 }
 781                 break;
 782         }
 783 #endif
 784         return offset;
 785 }
 786
 787 /* SunOS 5.x hardware capability descriptions */
 788 typedef struct cap_desc {
 789         uint64_t cd_mask;
 790         const char *cd_name;
 791 } cap_desc_t;
 792
 793 static const cap_desc_t cap_desc_sparc[] = {
 794         { AV_SPARC_MUL32,               "MUL32" },
 795         { AV_SPARC_DIV32,               "DIV32" },
 796         { AV_SPARC_FSMULD,              "FSMULD" },
 797         { AV_SPARC_V8PLUS,              "V8PLUS" },
 798         { AV_SPARC_POPC,                "POPC" },
 799         { AV_SPARC_VIS,                 "VIS" },
 800         { AV_SPARC_VIS2,                "VIS2" },
 801         { AV_SPARC_ASI_BLK_INIT,        "ASI_BLK_INIT" },
 802         { AV_SPARC_FMAF,                "FMAF" },
 803         { AV_SPARC_FJFMAU,              "FJFMAU" },
 804         { AV_SPARC_IMA,                 "IMA" },
 805         { 0, NULL }
 806 };
 807
 808 static const cap_desc_t cap_desc_386[] = {
 809         { AV_386_FPU,                   "FPU" },
 810         { AV_386_TSC,                   "TSC" },
 811         { AV_386_CX8,                   "CX8" },
 812         { AV_386_SEP,                   "SEP" },
 813         { AV_386_AMD_SYSC,              "AMD_SYSC" },
 814         { AV_386_CMOV,                  "CMOV" },
 815         { AV_386_MMX,                   "MMX" },
 816         { AV_386_AMD_MMX,               "AMD_MMX" },
 817         { AV_386_AMD_3DNow,             "AMD_3DNow" },
 818         { AV_386_AMD_3DNowx,            "AMD_3DNowx" },
 819         { AV_386_FXSR,                  "FXSR" },
 820         { AV_386_SSE,                   "SSE" },
 821         { AV_386_SSE2,                  "SSE2" },
 822         { AV_386_PAUSE,                 "PAUSE" },
 823         { AV_386_SSE3,                  "SSE3" },
 824         { AV_386_MON,                   "MON" },
 825         { AV_386_CX16,                  "CX16" },
 826         { AV_386_AHF,                   "AHF" },
 827         { AV_386_TSCP,                  "TSCP" },
 828         { AV_386_AMD_SSE4A,             "AMD_SSE4A" },
 829         { AV_386_POPCNT,                "POPCNT" },
 830         { AV_386_AMD_LZCNT,             "AMD_LZCNT" },
 831         { AV_386_SSSE3,                 "SSSE3" },
 832         { AV_386_SSE4_1,                "SSE4.1" },
 833         { AV_386_SSE4_2,                "SSE4.2" },
 834         { 0, NULL }
 835 };
 836
 837 private int
 838 doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
 839     size_t size, int *flags, int mach)
 840 {
 841         Elf32_Shdr sh32;
 842         Elf64_Shdr sh64;
 843         int stripped = 1;
 844         void *nbuf;
 845         off_t noff;
 846         uint64_t cap_hw1 = 0;   /* SunOS 5.x hardware capabilites */
 847         uint64_t cap_sf1 = 0;   /* SunOS 5.x software capabilites */
 848
 849         if (size != xsh_sizeof) {
 850                 if (file_printf(ms, ", corrupted section header size") == -1)
 851                         return -1;
 852                 return 0;
 853         }
 854
 855         if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
 856                 file_badseek(ms);
 857                 return -1;
 858         }
 859
 860         for ( ; num; num--) {
 861                 if (read(fd, xsh_addr, xsh_sizeof) == -1) {
 862                         file_badread(ms);
 863                         return -1;
 864                 }
 865                 switch (xsh_type) {
 866                 case SHT_SYMTAB:
 867 #if 0
 868                 case SHT_DYNSYM:
 869 #endif
 870                         stripped = 0;
 871                         break;
 872                 case SHT_NOTE:
 873                         if ((off = lseek(fd, (off_t)0, SEEK_CUR)) ==
 874                             (off_t)-1) {
 875                                 file_badread(ms);
 876                                 return -1;
 877                         }
 878                         if ((nbuf = malloc((size_t)xsh_size)) == NULL) {
 879                                 file_error(ms, errno, "Cannot allocate memory"
 880                                     " for note");
 881                                 return -1;
 882                         }
 883                         if ((noff = lseek(fd, (off_t)xsh_offset, SEEK_SET)) ==
 884                             (off_t)-1) {
 885                                 file_badread(ms);
 886                                 free(nbuf);
 887                                 return -1;
 888                         }
 889                         if (read(fd, nbuf, (size_t)xsh_size) !=
 890                             (ssize_t)xsh_size) {
 891                                 free(nbuf);
 892                                 file_badread(ms);
 893                                 return -1;
 894                         }
 895
 896                         noff = 0;
 897                         for (;;) {
 898                                 if (noff >= (off_t)xsh_size)
 899                                         break;
 900                                 noff = donote(ms, nbuf, (size_t)noff,
 901                                     (size_t)xsh_size, clazz, swap, 4,
 902                                     flags);
 903                                 if (noff == 0)
 904                                         break;
 905                         }
 906                         if ((lseek(fd, off, SEEK_SET)) == (off_t)-1) {
 907                                 free(nbuf);
 908                                 file_badread(ms);
 909                                 return -1;
 910                         }
 911                         free(nbuf);
 912                         break;
 913                 case SHT_SUNW_cap:
 914                     {
 915                         off_t coff;
 916                         if ((off = lseek(fd, (off_t)0, SEEK_CUR)) ==
 917                             (off_t)-1) {
 918                                 file_badread(ms);
 919                                 return -1;
 920                         }
 921                         if (lseek(fd, (off_t)xsh_offset, SEEK_SET) ==
 922                             (off_t)-1) {
 923                                 file_badread(ms);
 924                                 return -1;
 925                         }
 926                         coff = 0;
 927                         for (;;) {
 928                                 Elf32_Cap cap32;
 929                                 Elf64_Cap cap64;
 930                                 char cbuf[/*CONSTCOND*/
 931                                     MAX(sizeof cap32, sizeof cap64)];
 932                                 if ((coff += xcap_sizeof) > (off_t)xsh_size)
 933                                         break;
 934                                 if (read(fd, cbuf, (size_t)xcap_sizeof) !=
 935                                     (ssize_t)xcap_sizeof) {
 936                                         file_badread(ms);
 937                                         return -1;
 938                                 }
 939                                 (void)memcpy(xcap_addr, cbuf, xcap_sizeof);
 940                                 switch (xcap_tag) {
 941                                 case CA_SUNW_NULL:
 942                                         break;
 943                                 case CA_SUNW_HW_1:
 944                                         cap_hw1 |= xcap_val;
 945                                         break;
 946                                 case CA_SUNW_SF_1:
 947                                         cap_sf1 |= xcap_val;
 948                                         break;
 949                                 default:
 950                                         if (file_printf(ms,
 951                                             ", with unknown capability "
 952                                             "0x%" INT64_T_FORMAT "x = 0x%"
 953                                             INT64_T_FORMAT "x",
 954                                             (unsigned long long)xcap_tag,
 955                                             (unsigned long long)xcap_val) == -1)
 956                                                 return -1;
 957                                         break;
 958                                 }
 959                         }
 960                         if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
 961                                 file_badread(ms);
 962                                 return -1;
 963                         }
 964                         break;
 965                     }
 966                 }
 967         }
 968         if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1)
 969                 return -1;
 970         if (cap_hw1) {
 971                 const cap_desc_t *cdp;
 972                 switch (mach) {
 973                 case EM_SPARC:
 974                 case EM_SPARC32PLUS:
 975                 case EM_SPARCV9:
 976                         cdp = cap_desc_sparc;
 977                         break;
 978                 case EM_386:
 979                 case EM_IA_64:
 980                 case EM_AMD64:
 981                         cdp = cap_desc_386;
 982                         break;
 983                 default:
 984                         cdp = NULL;
 985                         break;
 986                 }
 987                 if (file_printf(ms, ", uses") == -1)
 988                         return -1;
 989                 if (cdp) {
 990                         while (cdp->cd_name) {
 991                                 if (cap_hw1 & cdp->cd_mask) {
 992                                         if (file_printf(ms,
 993                                             " %s", cdp->cd_name) == -1)
 994                                                 return -1;
 995                                         cap_hw1 &= ~cdp->cd_mask;
 996                                 }
 997                                 ++cdp;
 998                         }
 999                         if (cap_hw1)
1000                                 if (file_printf(ms,
1001                                     " unknown hardware capability 0x%"
1002                                     INT64_T_FORMAT "x",
1003                                     (unsigned long long)cap_hw1) == -1)
1004                                         return -1;
1005                 } else {
1006                         if (file_printf(ms,
1007                             " hardware capability 0x%" INT64_T_FORMAT "x",
1008                             (unsigned long long)cap_hw1) == -1)
1009                                 return -1;
1010                 }
1011         }
1012         if (cap_sf1) {
1013                 if (cap_sf1 & SF1_SUNW_FPUSED) {
1014                         if (file_printf(ms,
1015                             (cap_sf1 & SF1_SUNW_FPKNWN)
1016                             ? ", uses frame pointer"
1017                             : ", not known to use frame pointer") == -1)
1018                                 return -1;
1019                 }
1020                 cap_sf1 &= ~SF1_SUNW_MASK;
1021                 if (cap_sf1)
1022                         if (file_printf(ms,
1023                             ", with unknown software capability 0x%"
1024                             INT64_T_FORMAT "x",
1025                             (unsigned long long)cap_sf1) == -1)
1026                                 return -1;
1027         }
1028         return 0;
1029 }
1030
1031 /*
1032  * Look through the program headers of an executable image, searching
1033  * for a PT_INTERP section; if one is found, it's dynamically linked,
1034  * otherwise it's statically linked.
1035  */
1036 private int
1037 dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
1038     int num, size_t size, off_t fsize, int *flags, int sh_num)
1039 {
1040         Elf32_Phdr ph32;
1041         Elf64_Phdr ph64;
1042         const char *linking_style = "statically";
1043         const char *shared_libraries = "";
1044         unsigned char nbuf[BUFSIZ];
1045         ssize_t bufsize;
1046         size_t offset, align;
1047         off_t savedoffset = (off_t)-1;
1048         struct stat st;
1049
1050         if (fstat(fd, &st) < 0) {
1051                 file_badread(ms);
1052                 return -1;
1053         }
1054
1055         if (size != xph_sizeof) {
1056                 if (file_printf(ms, ", corrupted program header size") == -1)
1057                         return -1;
1058                 return 0;
1059         }
1060
1061         if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
1062                 file_badseek(ms);
1063                 return -1;
1064         }
1065
1066         for ( ; num; num--) {
1067                 if (read(fd, xph_addr, xph_sizeof) == -1) {
1068                         file_badread(ms);
1069                         return -1;
1070                 }
1071                 if (xph_offset > st.st_size && savedoffset != (off_t)-1) {
1072                         if (lseek(fd, savedoffset, SEEK_SET) == (off_t)-1) {
1073                                 file_badseek(ms);
1074                                 return -1;
1075                         }
1076                         continue;
1077                 }
1078
1079                 if ((savedoffset = lseek(fd, (off_t)0, SEEK_CUR)) == (off_t)-1) {
1080                         file_badseek(ms);
1081                         return -1;
1082                 }
1083
1084                 if (xph_offset > fsize) {
1085                         if (lseek(fd, savedoffset, SEEK_SET) == (off_t)-1) {
1086                                 file_badseek(ms);
1087                                 return -1;
1088                         }
1089                         continue;
1090                 }
1091
1092                 switch (xph_type) {
1093                 case PT_DYNAMIC:
1094                         linking_style = "dynamically";
1095                         break;
1096                 case PT_INTERP:
1097                         shared_libraries = " (uses shared libs)";
1098                         break;
1099                 case PT_NOTE:
1100                         if ((align = xph_align) & 0x80000000UL) {
1101                                 if (file_printf(ms,
1102                                     ", invalid note alignment 0x%lx",
1103                                     (unsigned long)align) == -1)
1104                                         return -1;
1105                                 align = 4;
1106                         }
1107                         if (sh_num)
1108                                 break;
1109                         /*
1110                          * This is a PT_NOTE section; loop through all the notes
1111                          * in the section.
1112                          */
1113                         if (lseek(fd, xph_offset, SEEK_SET)
1114                             == (off_t)-1) {
1115                                 file_badseek(ms);
1116                                 return -1;
1117                         }
1118                         bufsize = read(fd, nbuf, ((xph_filesz < sizeof(nbuf)) ?
1119                             xph_filesz : sizeof(nbuf)));
1120                         if (bufsize == -1) {
1121                                 file_badread(ms);
1122                                 return -1;
1123                         }
1124                         offset = 0;
1125                         for (;;) {
1126                                 if (offset >= (size_t)bufsize)
1127                                         break;
1128                                 offset = donote(ms, nbuf, offset,
1129                                     (size_t)bufsize, clazz, swap, align,
1130                                     flags);
1131                                 if (offset == 0)
1132                                         break;
1133                         }
1134                         if (lseek(fd, savedoffset, SEEK_SET) == (off_t)-1) {
1135                                 file_badseek(ms);
1136                                 return -1;
1137                         }
1138                         break;
1139                 default:
1140                         break;
1141                 }
1142         }
1143         if (file_printf(ms, ", %s linked%s", linking_style, shared_libraries)
1144             == -1)
1145             return -1;
1146         return 0;
1147 }
1148
1149
1150 protected int
1151 file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
1152     size_t nbytes)
1153 {
1154         union {
1155                 int32_t l;
1156                 char c[sizeof (int32_t)];
1157         } u;
1158         int clazz;
1159         int swap;
1160         struct stat st;
1161         off_t fsize;
1162         int flags = 0;
1163         Elf32_Ehdr elf32hdr;
1164         Elf64_Ehdr elf64hdr;
1165         uint16_t type;
1166
1167         if (ms->flags & (MAGIC_MIME|MAGIC_APPLE))
1168                 return 0;
1169         /*
1170          * ELF executables have multiple section headers in arbitrary
1171          * file locations and thus file(1) cannot determine it from easily.
1172          * Instead we traverse thru all section headers until a symbol table
1173          * one is found or else the binary is stripped.
1174          * Return immediately if it's not ELF (so we avoid pipe2file unless needed).
1175          */
1176         if (buf[EI_MAG0] != ELFMAG0
1177             || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
1178             || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
1179                 return 0;
1180
1181         /*
1182          * If we cannot seek, it must be a pipe, socket or fifo.
1183          */
1184         if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE))
1185                 fd = file_pipe2file(ms, fd, buf, nbytes);
1186
1187         if (fstat(fd, &st) == -1) {
1188                 file_badread(ms);
1189                 return -1;
1190         }
1191         fsize = st.st_size;
1192
1193         clazz = buf[EI_CLASS];
1194
1195         switch (clazz) {
1196         case ELFCLASS32:
1197 #undef elf_getu
1198 #define elf_getu(a, b)  elf_getu32(a, b)
1199 #undef elfhdr
1200 #define elfhdr elf32hdr
1201 #include "elfclass.h"
1202         case ELFCLASS64:
1203 #undef elf_getu
1204 #define elf_getu(a, b)  elf_getu64(a, b)
1205 #undef elfhdr
1206 #define elfhdr elf64hdr
1207 #include "elfclass.h"
1208         default:
1209             if (file_printf(ms, ", unknown class %d", clazz) == -1)
1210                     return -1;
1211             break;
1212         }
1213         return 0;
1214 }
1215 #endif