readelf.c revision 299236
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 30FILE_RCSID("@(#)$File: readelf.c,v 1.122 2015/09/10 13:59:32 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 45private int dophn_core(struct magic_set *, int, int, int, off_t, int, size_t, 46 off_t, int *, uint16_t *); 47#endif 48private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t, 49 off_t, int, int *, uint16_t *); 50private int doshn(struct magic_set *, int, int, int, off_t, int, size_t, 51 off_t, int, int, int *, uint16_t *); 52private size_t donote(struct magic_set *, void *, size_t, size_t, int, 53 int, size_t, int *, uint16_t *); 54 55#define ELF_ALIGN(a) ((((a) + align - 1) / align) * align) 56 57#define isquote(c) (strchr("'\"`", (c)) != NULL) 58 59private uint16_t getu16(int, uint16_t); 60private uint32_t getu32(int, uint32_t); 61private 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 67private int 68toomany(struct magic_set *ms, const char *name, uint16_t num) 69{ 70 if (file_printf(ms, ", too many %s (%u)", name, num 71 ) == -1) 72 return -1; 73 return 0; 74} 75 76private uint16_t 77getu16(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 95private uint32_t 96getu32(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 116private uint64_t 117getu64(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 */ 222static 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 237static 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 290private const char os_style_names[][8] = { 291 "SVR4", 292 "FreeBSD", 293 "NetBSD", 294}; 295 296#define FLAGS_DID_CORE 0x001 297#define FLAGS_DID_OS_NOTE 0x002 298#define FLAGS_DID_BUILD_ID 0x004 299#define FLAGS_DID_CORE_STYLE 0x008 300#define FLAGS_DID_NETBSD_PAX 0x010 301#define FLAGS_DID_NETBSD_MARCH 0x020 302#define FLAGS_DID_NETBSD_CMODEL 0x040 303#define FLAGS_DID_NETBSD_UNKNOWN 0x080 304#define FLAGS_IS_CORE 0x100 305 306private int 307dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off, 308 int num, size_t size, off_t fsize, int *flags, uint16_t *notecount) 309{ 310 Elf32_Phdr ph32; 311 Elf64_Phdr ph64; 312 size_t offset, len; 313 unsigned char nbuf[BUFSIZ]; 314 ssize_t bufsize; 315 316 if (size != xph_sizeof) { 317 if (file_printf(ms, ", corrupted program header size") == -1) 318 return -1; 319 return 0; 320 } 321 322 /* 323 * Loop through all the program headers. 324 */ 325 for ( ; num; num--) { 326 if (pread(fd, xph_addr, xph_sizeof, off) < (ssize_t)xph_sizeof) { 327 file_badread(ms); 328 return -1; 329 } 330 off += size; 331 332 if (fsize != SIZE_UNKNOWN && xph_offset > fsize) { 333 /* Perhaps warn here */ 334 continue; 335 } 336 337 if (xph_type != PT_NOTE) 338 continue; 339 340 /* 341 * This is a PT_NOTE section; loop through all the notes 342 * in the section. 343 */ 344 len = xph_filesz < sizeof(nbuf) ? xph_filesz : sizeof(nbuf); 345 if ((bufsize = pread(fd, nbuf, len, xph_offset)) == -1) { 346 file_badread(ms); 347 return -1; 348 } 349 offset = 0; 350 for (;;) { 351 if (offset >= (size_t)bufsize) 352 break; 353 offset = donote(ms, nbuf, offset, (size_t)bufsize, 354 clazz, swap, 4, flags, notecount); 355 if (offset == 0) 356 break; 357 358 } 359 } 360 return 0; 361} 362#endif 363 364static void 365do_note_netbsd_version(struct magic_set *ms, int swap, void *v) 366{ 367 uint32_t desc; 368 (void)memcpy(&desc, v, sizeof(desc)); 369 desc = elf_getu32(swap, desc); 370 371 if (file_printf(ms, ", for NetBSD") == -1) 372 return; 373 /* 374 * The version number used to be stuck as 199905, and was thus 375 * basically content-free. Newer versions of NetBSD have fixed 376 * this and now use the encoding of __NetBSD_Version__: 377 * 378 * MMmmrrpp00 379 * 380 * M = major version 381 * m = minor version 382 * r = release ["",A-Z,Z[A-Z] but numeric] 383 * p = patchlevel 384 */ 385 if (desc > 100000000U) { 386 uint32_t ver_patch = (desc / 100) % 100; 387 uint32_t ver_rel = (desc / 10000) % 100; 388 uint32_t ver_min = (desc / 1000000) % 100; 389 uint32_t ver_maj = desc / 100000000; 390 391 if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1) 392 return; 393 if (ver_rel == 0 && ver_patch != 0) { 394 if (file_printf(ms, ".%u", ver_patch) == -1) 395 return; 396 } else if (ver_rel != 0) { 397 while (ver_rel > 26) { 398 if (file_printf(ms, "Z") == -1) 399 return; 400 ver_rel -= 26; 401 } 402 if (file_printf(ms, "%c", 'A' + ver_rel - 1) 403 == -1) 404 return; 405 } 406 } 407} 408 409static void 410do_note_freebsd_version(struct magic_set *ms, int swap, void *v) 411{ 412 uint32_t desc; 413 414 (void)memcpy(&desc, v, sizeof(desc)); 415 desc = elf_getu32(swap, desc); 416 if (file_printf(ms, ", for FreeBSD") == -1) 417 return; 418 419 /* 420 * Contents is __FreeBSD_version, whose relation to OS 421 * versions is defined by a huge table in the Porter's 422 * Handbook. This is the general scheme: 423 * 424 * Releases: 425 * Mmp000 (before 4.10) 426 * Mmi0p0 (before 5.0) 427 * Mmm0p0 428 * 429 * Development branches: 430 * Mmpxxx (before 4.6) 431 * Mmp1xx (before 4.10) 432 * Mmi1xx (before 5.0) 433 * M000xx (pre-M.0) 434 * Mmm1xx 435 * 436 * M = major version 437 * m = minor version 438 * i = minor version increment (491000 -> 4.10) 439 * p = patchlevel 440 * x = revision 441 * 442 * The first release of FreeBSD to use ELF by default 443 * was version 3.0. 444 */ 445 if (desc == 460002) { 446 if (file_printf(ms, " 4.6.2") == -1) 447 return; 448 } else if (desc < 460100) { 449 if (file_printf(ms, " %d.%d", desc / 100000, 450 desc / 10000 % 10) == -1) 451 return; 452 if (desc / 1000 % 10 > 0) 453 if (file_printf(ms, ".%d", desc / 1000 % 10) == -1) 454 return; 455 if ((desc % 1000 > 0) || (desc % 100000 == 0)) 456 if (file_printf(ms, " (%d)", desc) == -1) 457 return; 458 } else if (desc < 500000) { 459 if (file_printf(ms, " %d.%d", desc / 100000, 460 desc / 10000 % 10 + desc / 1000 % 10) == -1) 461 return; 462 if (desc / 100 % 10 > 0) { 463 if (file_printf(ms, " (%d)", desc) == -1) 464 return; 465 } else if (desc / 10 % 10 > 0) { 466 if (file_printf(ms, ".%d", desc / 10 % 10) == -1) 467 return; 468 } 469 } else { 470 if (file_printf(ms, " %d.%d", desc / 100000, 471 desc / 1000 % 100) == -1) 472 return; 473 if ((desc / 100 % 10 > 0) || 474 (desc % 100000 / 100 == 0)) { 475 if (file_printf(ms, " (%d)", desc) == -1) 476 return; 477 } else if (desc / 10 % 10 > 0) { 478 if (file_printf(ms, ".%d", desc / 10 % 10) == -1) 479 return; 480 } 481 } 482} 483 484private int 485/*ARGSUSED*/ 486do_bid_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, 487 int swap __attribute__((__unused__)), uint32_t namesz, uint32_t descsz, 488 size_t noff, size_t doff, int *flags) 489{ 490 if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 && 491 type == NT_GNU_BUILD_ID && (descsz == 16 || descsz == 20)) { 492 uint8_t desc[20]; 493 uint32_t i; 494 *flags |= FLAGS_DID_BUILD_ID; 495 if (file_printf(ms, ", BuildID[%s]=", descsz == 16 ? "md5/uuid" : 496 "sha1") == -1) 497 return 1; 498 (void)memcpy(desc, &nbuf[doff], descsz); 499 for (i = 0; i < descsz; i++) 500 if (file_printf(ms, "%02x", desc[i]) == -1) 501 return 1; 502 return 1; 503 } 504 return 0; 505} 506 507private int 508do_os_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, 509 int swap, uint32_t namesz, uint32_t descsz, 510 size_t noff, size_t doff, int *flags) 511{ 512 if (namesz == 5 && strcmp((char *)&nbuf[noff], "SuSE") == 0 && 513 type == NT_GNU_VERSION && descsz == 2) { 514 *flags |= FLAGS_DID_OS_NOTE; 515 file_printf(ms, ", for SuSE %d.%d", nbuf[doff], nbuf[doff + 1]); 516 return 1; 517 } 518 519 if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 && 520 type == NT_GNU_VERSION && descsz == 16) { 521 uint32_t desc[4]; 522 (void)memcpy(desc, &nbuf[doff], sizeof(desc)); 523 524 *flags |= FLAGS_DID_OS_NOTE; 525 if (file_printf(ms, ", for GNU/") == -1) 526 return 1; 527 switch (elf_getu32(swap, desc[0])) { 528 case GNU_OS_LINUX: 529 if (file_printf(ms, "Linux") == -1) 530 return 1; 531 break; 532 case GNU_OS_HURD: 533 if (file_printf(ms, "Hurd") == -1) 534 return 1; 535 break; 536 case GNU_OS_SOLARIS: 537 if (file_printf(ms, "Solaris") == -1) 538 return 1; 539 break; 540 case GNU_OS_KFREEBSD: 541 if (file_printf(ms, "kFreeBSD") == -1) 542 return 1; 543 break; 544 case GNU_OS_KNETBSD: 545 if (file_printf(ms, "kNetBSD") == -1) 546 return 1; 547 break; 548 default: 549 if (file_printf(ms, "<unknown>") == -1) 550 return 1; 551 } 552 if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]), 553 elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1) 554 return 1; 555 return 1; 556 } 557 558 if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0) { 559 if (type == NT_NETBSD_VERSION && descsz == 4) { 560 *flags |= FLAGS_DID_OS_NOTE; 561 do_note_netbsd_version(ms, swap, &nbuf[doff]); 562 return 1; 563 } 564 } 565 566 if (namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0) { 567 if (type == NT_FREEBSD_VERSION && descsz == 4) { 568 *flags |= FLAGS_DID_OS_NOTE; 569 do_note_freebsd_version(ms, swap, &nbuf[doff]); 570 return 1; 571 } 572 } 573 574 if (namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 && 575 type == NT_OPENBSD_VERSION && descsz == 4) { 576 *flags |= FLAGS_DID_OS_NOTE; 577 if (file_printf(ms, ", for OpenBSD") == -1) 578 return 1; 579 /* Content of note is always 0 */ 580 return 1; 581 } 582 583 if (namesz == 10 && strcmp((char *)&nbuf[noff], "DragonFly") == 0 && 584 type == NT_DRAGONFLY_VERSION && descsz == 4) { 585 uint32_t desc; 586 *flags |= FLAGS_DID_OS_NOTE; 587 if (file_printf(ms, ", for DragonFly") == -1) 588 return 1; 589 (void)memcpy(&desc, &nbuf[doff], sizeof(desc)); 590 desc = elf_getu32(swap, desc); 591 if (file_printf(ms, " %d.%d.%d", desc / 100000, 592 desc / 10000 % 10, desc % 10000) == -1) 593 return 1; 594 return 1; 595 } 596 return 0; 597} 598 599private int 600do_pax_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, 601 int swap, uint32_t namesz, uint32_t descsz, 602 size_t noff, size_t doff, int *flags) 603{ 604 if (namesz == 4 && strcmp((char *)&nbuf[noff], "PaX") == 0 && 605 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 *flags |= FLAGS_DID_NETBSD_PAX; 619 (void)memcpy(&desc, &nbuf[doff], sizeof(desc)); 620 desc = elf_getu32(swap, desc); 621 622 if (desc && file_printf(ms, ", PaX: ") == -1) 623 return 1; 624 625 for (i = 0; i < __arraycount(pax); i++) { 626 if (((1 << (int)i) & desc) == 0) 627 continue; 628 if (file_printf(ms, "%s%s", did++ ? "," : "", 629 pax[i]) == -1) 630 return 1; 631 } 632 return 1; 633 } 634 return 0; 635} 636 637private int 638do_core_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, 639 int swap, uint32_t namesz, uint32_t descsz, 640 size_t noff, size_t doff, int *flags, size_t size, int clazz) 641{ 642#ifdef ELFCORE 643 int os_style = -1; 644 /* 645 * Sigh. The 2.0.36 kernel in Debian 2.1, at 646 * least, doesn't correctly implement name 647 * sections, in core dumps, as specified by 648 * the "Program Linking" section of "UNIX(R) System 649 * V Release 4 Programmer's Guide: ANSI C and 650 * Programming Support Tools", because my copy 651 * clearly says "The first 'namesz' bytes in 'name' 652 * contain a *null-terminated* [emphasis mine] 653 * character representation of the entry's owner 654 * or originator", but the 2.0.36 kernel code 655 * doesn't include the terminating null in the 656 * name.... 657 */ 658 if ((namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) || 659 (namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) { 660 os_style = OS_STYLE_SVR4; 661 } 662 663 if ((namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) { 664 os_style = OS_STYLE_FREEBSD; 665 } 666 667 if ((namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11) 668 == 0)) { 669 os_style = OS_STYLE_NETBSD; 670 } 671 672 if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) { 673 if (file_printf(ms, ", %s-style", os_style_names[os_style]) 674 == -1) 675 return 1; 676 *flags |= FLAGS_DID_CORE_STYLE; 677 } 678 679 switch (os_style) { 680 case OS_STYLE_NETBSD: 681 if (type == NT_NETBSD_CORE_PROCINFO) { 682 char sbuf[512]; 683 uint32_t signo; 684 /* 685 * Extract the program name. It is at 686 * offset 0x7c, and is up to 32-bytes, 687 * including the terminating NUL. 688 */ 689 if (file_printf(ms, ", from '%.31s'", 690 file_printable(sbuf, sizeof(sbuf), 691 (const char *)&nbuf[doff + 0x7c])) == -1) 692 return 1; 693 694 /* 695 * Extract the signal number. It is at 696 * offset 0x08. 697 */ 698 (void)memcpy(&signo, &nbuf[doff + 0x08], 699 sizeof(signo)); 700 if (file_printf(ms, " (signal %u)", 701 elf_getu32(swap, signo)) == -1) 702 return 1; 703 *flags |= FLAGS_DID_CORE; 704 return 1; 705 } 706 break; 707 708 default: 709 if (type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) { 710 size_t i, j; 711 unsigned char c; 712 /* 713 * Extract the program name. We assume 714 * it to be 16 characters (that's what it 715 * is in SunOS 5.x and Linux). 716 * 717 * Unfortunately, it's at a different offset 718 * in various OSes, so try multiple offsets. 719 * If the characters aren't all printable, 720 * reject it. 721 */ 722 for (i = 0; i < NOFFSETS; i++) { 723 unsigned char *cname, *cp; 724 size_t reloffset = prpsoffsets(i); 725 size_t noffset = doff + reloffset; 726 size_t k; 727 for (j = 0; j < 16; j++, noffset++, 728 reloffset++) { 729 /* 730 * Make sure we're not past 731 * the end of the buffer; if 732 * we are, just give up. 733 */ 734 if (noffset >= size) 735 goto tryanother; 736 737 /* 738 * Make sure we're not past 739 * the end of the contents; 740 * if we are, this obviously 741 * isn't the right offset. 742 */ 743 if (reloffset >= descsz) 744 goto tryanother; 745 746 c = nbuf[noffset]; 747 if (c == '\0') { 748 /* 749 * A '\0' at the 750 * beginning is 751 * obviously wrong. 752 * Any other '\0' 753 * means we're done. 754 */ 755 if (j == 0) 756 goto tryanother; 757 else 758 break; 759 } else { 760 /* 761 * A nonprintable 762 * character is also 763 * wrong. 764 */ 765 if (!isprint(c) || isquote(c)) 766 goto tryanother; 767 } 768 } 769 /* 770 * Well, that worked. 771 */ 772 773 /* 774 * Try next offsets, in case this match is 775 * in the middle of a string. 776 */ 777 for (k = i + 1 ; k < NOFFSETS; k++) { 778 size_t no; 779 int adjust = 1; 780 if (prpsoffsets(k) >= prpsoffsets(i)) 781 continue; 782 for (no = doff + prpsoffsets(k); 783 no < doff + prpsoffsets(i); no++) 784 adjust = adjust 785 && isprint(nbuf[no]); 786 if (adjust) 787 i = k; 788 } 789 790 cname = (unsigned char *) 791 &nbuf[doff + prpsoffsets(i)]; 792 for (cp = cname; *cp && isprint(*cp); cp++) 793 continue; 794 /* 795 * Linux apparently appends a space at the end 796 * of the command line: remove it. 797 */ 798 while (cp > cname && isspace(cp[-1])) 799 cp--; 800 if (file_printf(ms, ", from '%.*s'", 801 (int)(cp - cname), cname) == -1) 802 return 1; 803 *flags |= FLAGS_DID_CORE; 804 return 1; 805 806 tryanother: 807 ; 808 } 809 } 810 break; 811 } 812#endif 813 return 0; 814} 815 816private size_t 817donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size, 818 int clazz, int swap, size_t align, int *flags, uint16_t *notecount) 819{ 820 Elf32_Nhdr nh32; 821 Elf64_Nhdr nh64; 822 size_t noff, doff; 823 uint32_t namesz, descsz; 824 unsigned char *nbuf = CAST(unsigned char *, vbuf); 825 826 if (*notecount == 0) 827 return 0; 828 --*notecount; 829 830 if (xnh_sizeof + offset > size) { 831 /* 832 * We're out of note headers. 833 */ 834 return xnh_sizeof + offset; 835 } 836 837 (void)memcpy(xnh_addr, &nbuf[offset], xnh_sizeof); 838 offset += xnh_sizeof; 839 840 namesz = xnh_namesz; 841 descsz = xnh_descsz; 842 if ((namesz == 0) && (descsz == 0)) { 843 /* 844 * We're out of note headers. 845 */ 846 return (offset >= size) ? offset : size; 847 } 848 849 if (namesz & 0x80000000) { 850 (void)file_printf(ms, ", bad note name size 0x%lx", 851 (unsigned long)namesz); 852 return 0; 853 } 854 855 if (descsz & 0x80000000) { 856 (void)file_printf(ms, ", bad note description size 0x%lx", 857 (unsigned long)descsz); 858 return 0; 859 } 860 861 noff = offset; 862 doff = ELF_ALIGN(offset + namesz); 863 864 if (offset + namesz > size) { 865 /* 866 * We're past the end of the buffer. 867 */ 868 return doff; 869 } 870 871 offset = ELF_ALIGN(doff + descsz); 872 if (doff + descsz > size) { 873 /* 874 * We're past the end of the buffer. 875 */ 876 return (offset >= size) ? offset : size; 877 } 878 879 if ((*flags & FLAGS_DID_OS_NOTE) == 0) { 880 if (do_os_note(ms, nbuf, xnh_type, swap, 881 namesz, descsz, noff, doff, flags)) 882 return size; 883 } 884 885 if ((*flags & FLAGS_DID_BUILD_ID) == 0) { 886 if (do_bid_note(ms, nbuf, xnh_type, swap, 887 namesz, descsz, noff, doff, flags)) 888 return size; 889 } 890 891 if ((*flags & FLAGS_DID_NETBSD_PAX) == 0) { 892 if (do_pax_note(ms, nbuf, xnh_type, swap, 893 namesz, descsz, noff, doff, flags)) 894 return size; 895 } 896 897 if ((*flags & FLAGS_DID_CORE) == 0) { 898 if (do_core_note(ms, nbuf, xnh_type, swap, 899 namesz, descsz, noff, doff, flags, size, clazz)) 900 return size; 901 } 902 903 if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0) { 904 if (descsz > 100) 905 descsz = 100; 906 switch (xnh_type) { 907 case NT_NETBSD_VERSION: 908 return size; 909 case NT_NETBSD_MARCH: 910 if (*flags & FLAGS_DID_NETBSD_MARCH) 911 return size; 912 *flags |= FLAGS_DID_NETBSD_MARCH; 913 if (file_printf(ms, ", compiled for: %.*s", 914 (int)descsz, (const char *)&nbuf[doff]) == -1) 915 return size; 916 break; 917 case NT_NETBSD_CMODEL: 918 if (*flags & FLAGS_DID_NETBSD_CMODEL) 919 return size; 920 *flags |= FLAGS_DID_NETBSD_CMODEL; 921 if (file_printf(ms, ", compiler model: %.*s", 922 (int)descsz, (const char *)&nbuf[doff]) == -1) 923 return size; 924 break; 925 default: 926 if (*flags & FLAGS_DID_NETBSD_UNKNOWN) 927 return size; 928 *flags |= FLAGS_DID_NETBSD_UNKNOWN; 929 if (file_printf(ms, ", note=%u", xnh_type) == -1) 930 return size; 931 break; 932 } 933 return size; 934 } 935 936 return offset; 937} 938 939/* SunOS 5.x hardware capability descriptions */ 940typedef struct cap_desc { 941 uint64_t cd_mask; 942 const char *cd_name; 943} cap_desc_t; 944 945static const cap_desc_t cap_desc_sparc[] = { 946 { AV_SPARC_MUL32, "MUL32" }, 947 { AV_SPARC_DIV32, "DIV32" }, 948 { AV_SPARC_FSMULD, "FSMULD" }, 949 { AV_SPARC_V8PLUS, "V8PLUS" }, 950 { AV_SPARC_POPC, "POPC" }, 951 { AV_SPARC_VIS, "VIS" }, 952 { AV_SPARC_VIS2, "VIS2" }, 953 { AV_SPARC_ASI_BLK_INIT, "ASI_BLK_INIT" }, 954 { AV_SPARC_FMAF, "FMAF" }, 955 { AV_SPARC_FJFMAU, "FJFMAU" }, 956 { AV_SPARC_IMA, "IMA" }, 957 { 0, NULL } 958}; 959 960static const cap_desc_t cap_desc_386[] = { 961 { AV_386_FPU, "FPU" }, 962 { AV_386_TSC, "TSC" }, 963 { AV_386_CX8, "CX8" }, 964 { AV_386_SEP, "SEP" }, 965 { AV_386_AMD_SYSC, "AMD_SYSC" }, 966 { AV_386_CMOV, "CMOV" }, 967 { AV_386_MMX, "MMX" }, 968 { AV_386_AMD_MMX, "AMD_MMX" }, 969 { AV_386_AMD_3DNow, "AMD_3DNow" }, 970 { AV_386_AMD_3DNowx, "AMD_3DNowx" }, 971 { AV_386_FXSR, "FXSR" }, 972 { AV_386_SSE, "SSE" }, 973 { AV_386_SSE2, "SSE2" }, 974 { AV_386_PAUSE, "PAUSE" }, 975 { AV_386_SSE3, "SSE3" }, 976 { AV_386_MON, "MON" }, 977 { AV_386_CX16, "CX16" }, 978 { AV_386_AHF, "AHF" }, 979 { AV_386_TSCP, "TSCP" }, 980 { AV_386_AMD_SSE4A, "AMD_SSE4A" }, 981 { AV_386_POPCNT, "POPCNT" }, 982 { AV_386_AMD_LZCNT, "AMD_LZCNT" }, 983 { AV_386_SSSE3, "SSSE3" }, 984 { AV_386_SSE4_1, "SSE4.1" }, 985 { AV_386_SSE4_2, "SSE4.2" }, 986 { 0, NULL } 987}; 988 989private int 990doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num, 991 size_t size, off_t fsize, int mach, int strtab, int *flags, 992 uint16_t *notecount) 993{ 994 Elf32_Shdr sh32; 995 Elf64_Shdr sh64; 996 int stripped = 1; 997 size_t nbadcap = 0; 998 void *nbuf; 999 off_t noff, coff, name_off; 1000 uint64_t cap_hw1 = 0; /* SunOS 5.x hardware capabilites */ 1001 uint64_t cap_sf1 = 0; /* SunOS 5.x software capabilites */ 1002 char name[50]; 1003 ssize_t namesize; 1004 1005 if (size != xsh_sizeof) { 1006 if (file_printf(ms, ", corrupted section header size") == -1) 1007 return -1; 1008 return 0; 1009 } 1010 1011 /* Read offset of name section to be able to read section names later */ 1012 if (pread(fd, xsh_addr, xsh_sizeof, CAST(off_t, (off + size * strtab))) 1013 < (ssize_t)xsh_sizeof) { 1014 file_badread(ms); 1015 return -1; 1016 } 1017 name_off = xsh_offset; 1018 1019 for ( ; num; num--) { 1020 /* Read the name of this section. */ 1021 if ((namesize = pread(fd, name, sizeof(name) - 1, name_off + xsh_name)) == -1) { 1022 file_badread(ms); 1023 return -1; 1024 } 1025 name[namesize] = '\0'; 1026 if (strcmp(name, ".debug_info") == 0) 1027 stripped = 0; 1028 1029 if (pread(fd, xsh_addr, xsh_sizeof, off) < (ssize_t)xsh_sizeof) { 1030 file_badread(ms); 1031 return -1; 1032 } 1033 off += size; 1034 1035 /* Things we can determine before we seek */ 1036 switch (xsh_type) { 1037 case SHT_SYMTAB: 1038#if 0 1039 case SHT_DYNSYM: 1040#endif 1041 stripped = 0; 1042 break; 1043 default: 1044 if (fsize != SIZE_UNKNOWN && xsh_offset > fsize) { 1045 /* Perhaps warn here */ 1046 continue; 1047 } 1048 break; 1049 } 1050 1051 1052 /* Things we can determine when we seek */ 1053 switch (xsh_type) { 1054 case SHT_NOTE: 1055 if ((uintmax_t)(xsh_size + xsh_offset) > 1056 (uintmax_t)fsize) { 1057 if (file_printf(ms, 1058 ", note offset/size 0x%" INTMAX_T_FORMAT 1059 "x+0x%" INTMAX_T_FORMAT "x exceeds" 1060 " file size 0x%" INTMAX_T_FORMAT "x", 1061 (uintmax_t)xsh_offset, (uintmax_t)xsh_size, 1062 (uintmax_t)fsize) == -1) 1063 return -1; 1064 return 0; 1065 } 1066 if ((nbuf = malloc(xsh_size)) == NULL) { 1067 file_error(ms, errno, "Cannot allocate memory" 1068 " for note"); 1069 return -1; 1070 } 1071 if (pread(fd, nbuf, xsh_size, xsh_offset) < 1072 (ssize_t)xsh_size) { 1073 file_badread(ms); 1074 free(nbuf); 1075 return -1; 1076 } 1077 1078 noff = 0; 1079 for (;;) { 1080 if (noff >= (off_t)xsh_size) 1081 break; 1082 noff = donote(ms, nbuf, (size_t)noff, 1083 xsh_size, clazz, swap, 4, flags, notecount); 1084 if (noff == 0) 1085 break; 1086 } 1087 free(nbuf); 1088 break; 1089 case SHT_SUNW_cap: 1090 switch (mach) { 1091 case EM_SPARC: 1092 case EM_SPARCV9: 1093 case EM_IA_64: 1094 case EM_386: 1095 case EM_AMD64: 1096 break; 1097 default: 1098 goto skip; 1099 } 1100 1101 if (nbadcap > 5) 1102 break; 1103 if (lseek(fd, xsh_offset, SEEK_SET) == (off_t)-1) { 1104 file_badseek(ms); 1105 return -1; 1106 } 1107 coff = 0; 1108 for (;;) { 1109 Elf32_Cap cap32; 1110 Elf64_Cap cap64; 1111 char cbuf[/*CONSTCOND*/ 1112 MAX(sizeof cap32, sizeof cap64)]; 1113 if ((coff += xcap_sizeof) > (off_t)xsh_size) 1114 break; 1115 if (read(fd, cbuf, (size_t)xcap_sizeof) != 1116 (ssize_t)xcap_sizeof) { 1117 file_badread(ms); 1118 return -1; 1119 } 1120 if (cbuf[0] == 'A') { 1121#ifdef notyet 1122 char *p = cbuf + 1; 1123 uint32_t len, tag; 1124 memcpy(&len, p, sizeof(len)); 1125 p += 4; 1126 len = getu32(swap, len); 1127 if (memcmp("gnu", p, 3) != 0) { 1128 if (file_printf(ms, 1129 ", unknown capability %.3s", p) 1130 == -1) 1131 return -1; 1132 break; 1133 } 1134 p += strlen(p) + 1; 1135 tag = *p++; 1136 memcpy(&len, p, sizeof(len)); 1137 p += 4; 1138 len = getu32(swap, len); 1139 if (tag != 1) { 1140 if (file_printf(ms, ", unknown gnu" 1141 " capability tag %d", tag) 1142 == -1) 1143 return -1; 1144 break; 1145 } 1146 // gnu attributes 1147#endif 1148 break; 1149 } 1150 (void)memcpy(xcap_addr, cbuf, xcap_sizeof); 1151 switch (xcap_tag) { 1152 case CA_SUNW_NULL: 1153 break; 1154 case CA_SUNW_HW_1: 1155 cap_hw1 |= xcap_val; 1156 break; 1157 case CA_SUNW_SF_1: 1158 cap_sf1 |= xcap_val; 1159 break; 1160 default: 1161 if (file_printf(ms, 1162 ", with unknown capability " 1163 "0x%" INT64_T_FORMAT "x = 0x%" 1164 INT64_T_FORMAT "x", 1165 (unsigned long long)xcap_tag, 1166 (unsigned long long)xcap_val) == -1) 1167 return -1; 1168 if (nbadcap++ > 2) 1169 coff = xsh_size; 1170 break; 1171 } 1172 } 1173 /*FALLTHROUGH*/ 1174 skip: 1175 default: 1176 break; 1177 } 1178 } 1179 1180 if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1) 1181 return -1; 1182 if (cap_hw1) { 1183 const cap_desc_t *cdp; 1184 switch (mach) { 1185 case EM_SPARC: 1186 case EM_SPARC32PLUS: 1187 case EM_SPARCV9: 1188 cdp = cap_desc_sparc; 1189 break; 1190 case EM_386: 1191 case EM_IA_64: 1192 case EM_AMD64: 1193 cdp = cap_desc_386; 1194 break; 1195 default: 1196 cdp = NULL; 1197 break; 1198 } 1199 if (file_printf(ms, ", uses") == -1) 1200 return -1; 1201 if (cdp) { 1202 while (cdp->cd_name) { 1203 if (cap_hw1 & cdp->cd_mask) { 1204 if (file_printf(ms, 1205 " %s", cdp->cd_name) == -1) 1206 return -1; 1207 cap_hw1 &= ~cdp->cd_mask; 1208 } 1209 ++cdp; 1210 } 1211 if (cap_hw1) 1212 if (file_printf(ms, 1213 " unknown hardware capability 0x%" 1214 INT64_T_FORMAT "x", 1215 (unsigned long long)cap_hw1) == -1) 1216 return -1; 1217 } else { 1218 if (file_printf(ms, 1219 " hardware capability 0x%" INT64_T_FORMAT "x", 1220 (unsigned long long)cap_hw1) == -1) 1221 return -1; 1222 } 1223 } 1224 if (cap_sf1) { 1225 if (cap_sf1 & SF1_SUNW_FPUSED) { 1226 if (file_printf(ms, 1227 (cap_sf1 & SF1_SUNW_FPKNWN) 1228 ? ", uses frame pointer" 1229 : ", not known to use frame pointer") == -1) 1230 return -1; 1231 } 1232 cap_sf1 &= ~SF1_SUNW_MASK; 1233 if (cap_sf1) 1234 if (file_printf(ms, 1235 ", with unknown software capability 0x%" 1236 INT64_T_FORMAT "x", 1237 (unsigned long long)cap_sf1) == -1) 1238 return -1; 1239 } 1240 return 0; 1241} 1242 1243/* 1244 * Look through the program headers of an executable image, searching 1245 * for a PT_INTERP section; if one is found, it's dynamically linked, 1246 * otherwise it's statically linked. 1247 */ 1248private int 1249dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off, 1250 int num, size_t size, off_t fsize, int sh_num, int *flags, 1251 uint16_t *notecount) 1252{ 1253 Elf32_Phdr ph32; 1254 Elf64_Phdr ph64; 1255 const char *linking_style = "statically"; 1256 const char *interp = ""; 1257 unsigned char nbuf[BUFSIZ]; 1258 char ibuf[BUFSIZ]; 1259 ssize_t bufsize; 1260 size_t offset, align, len; 1261 1262 if (size != xph_sizeof) { 1263 if (file_printf(ms, ", corrupted program header size") == -1) 1264 return -1; 1265 return 0; 1266 } 1267 1268 for ( ; num; num--) { 1269 if (pread(fd, xph_addr, xph_sizeof, off) < (ssize_t)xph_sizeof) { 1270 file_badread(ms); 1271 return -1; 1272 } 1273 1274 off += size; 1275 bufsize = 0; 1276 align = 4; 1277 1278 /* Things we can determine before we seek */ 1279 switch (xph_type) { 1280 case PT_DYNAMIC: 1281 linking_style = "dynamically"; 1282 break; 1283 case PT_NOTE: 1284 if (sh_num) /* Did this through section headers */ 1285 continue; 1286 if (((align = xph_align) & 0x80000000UL) != 0 || 1287 align < 4) { 1288 if (file_printf(ms, 1289 ", invalid note alignment 0x%lx", 1290 (unsigned long)align) == -1) 1291 return -1; 1292 align = 4; 1293 } 1294 /*FALLTHROUGH*/ 1295 case PT_INTERP: 1296 len = xph_filesz < sizeof(nbuf) ? xph_filesz 1297 : sizeof(nbuf); 1298 bufsize = pread(fd, nbuf, len, xph_offset); 1299 if (bufsize == -1) { 1300 file_badread(ms); 1301 return -1; 1302 } 1303 break; 1304 default: 1305 if (fsize != SIZE_UNKNOWN && xph_offset > fsize) { 1306 /* Maybe warn here? */ 1307 continue; 1308 } 1309 break; 1310 } 1311 1312 /* Things we can determine when we seek */ 1313 switch (xph_type) { 1314 case PT_INTERP: 1315 if (bufsize && nbuf[0]) { 1316 nbuf[bufsize - 1] = '\0'; 1317 interp = (const char *)nbuf; 1318 } else 1319 interp = "*empty*"; 1320 break; 1321 case PT_NOTE: 1322 /* 1323 * This is a PT_NOTE section; loop through all the notes 1324 * in the section. 1325 */ 1326 offset = 0; 1327 for (;;) { 1328 if (offset >= (size_t)bufsize) 1329 break; 1330 offset = donote(ms, nbuf, offset, 1331 (size_t)bufsize, clazz, swap, align, 1332 flags, notecount); 1333 if (offset == 0) 1334 break; 1335 } 1336 break; 1337 default: 1338 break; 1339 } 1340 } 1341 if (file_printf(ms, ", %s linked", linking_style) 1342 == -1) 1343 return -1; 1344 if (interp[0]) 1345 if (file_printf(ms, ", interpreter %s", 1346 file_printable(ibuf, sizeof(ibuf), interp)) == -1) 1347 return -1; 1348 return 0; 1349} 1350 1351 1352protected int 1353file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf, 1354 size_t nbytes) 1355{ 1356 union { 1357 int32_t l; 1358 char c[sizeof (int32_t)]; 1359 } u; 1360 int clazz; 1361 int swap; 1362 struct stat st; 1363 off_t fsize; 1364 int flags = 0; 1365 Elf32_Ehdr elf32hdr; 1366 Elf64_Ehdr elf64hdr; 1367 uint16_t type, phnum, shnum, notecount; 1368 1369 if (ms->flags & (MAGIC_MIME|MAGIC_APPLE|MAGIC_EXTENSION)) 1370 return 0; 1371 /* 1372 * ELF executables have multiple section headers in arbitrary 1373 * file locations and thus file(1) cannot determine it from easily. 1374 * Instead we traverse thru all section headers until a symbol table 1375 * one is found or else the binary is stripped. 1376 * Return immediately if it's not ELF (so we avoid pipe2file unless needed). 1377 */ 1378 if (buf[EI_MAG0] != ELFMAG0 1379 || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1) 1380 || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3) 1381 return 0; 1382 1383 /* 1384 * If we cannot seek, it must be a pipe, socket or fifo. 1385 */ 1386 if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE)) 1387 fd = file_pipe2file(ms, fd, buf, nbytes); 1388 1389 if (fstat(fd, &st) == -1) { 1390 file_badread(ms); 1391 return -1; 1392 } 1393 if (S_ISREG(st.st_mode) || st.st_size != 0) 1394 fsize = st.st_size; 1395 else 1396 fsize = SIZE_UNKNOWN; 1397 1398 clazz = buf[EI_CLASS]; 1399 1400 switch (clazz) { 1401 case ELFCLASS32: 1402#undef elf_getu 1403#define elf_getu(a, b) elf_getu32(a, b) 1404#undef elfhdr 1405#define elfhdr elf32hdr 1406#include "elfclass.h" 1407 case ELFCLASS64: 1408#undef elf_getu 1409#define elf_getu(a, b) elf_getu64(a, b) 1410#undef elfhdr 1411#define elfhdr elf64hdr 1412#include "elfclass.h" 1413 default: 1414 if (file_printf(ms, ", unknown class %d", clazz) == -1) 1415 return -1; 1416 break; 1417 } 1418 return 0; 1419} 1420#endif 1421