xref: /dflybsd-src/contrib/file/src/readelf.c (revision e90a7c45c3303ed54c0fde732b2ba32dc80ffd9b)
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
1216