xref: /freebsd/contrib/file/src/readelf.c (revision 4232f826683298e85d469c0ef17259cecd13b2c7)
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 1.119 2015/04/09 20:01:41 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 *, uint16_t *);
47 #endif
48 private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t,
49     off_t, int, int *, uint16_t *);
50 private int doshn(struct magic_set *, int, int, int, off_t, int, size_t,
51     off_t, int, int, int *, uint16_t *);
52 private 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 
59 private uint16_t getu16(int, uint16_t);
60 private uint32_t getu32(int, uint32_t);
61 private uint64_t getu64(int, uint64_t);
62 
63 #define MAX_PHNUM	128
64 #define	MAX_SHNUM	32768
65 #define SIZE_UNKNOWN	((off_t)-1)
66 
67 private int
68 toomany(struct magic_set *ms, const char *name, uint16_t num)
69 {
70 	if (file_printf(ms, ", too many %s (%u)", name, num
71 	    ) == -1)
72 		return -1;
73 	return 0;
74 }
75 
76 private uint16_t
77 getu16(int swap, uint16_t value)
78 {
79 	union {
80 		uint16_t ui;
81 		char c[2];
82 	} retval, tmpval;
83 
84 	if (swap) {
85 		tmpval.ui = value;
86 
87 		retval.c[0] = tmpval.c[1];
88 		retval.c[1] = tmpval.c[0];
89 
90 		return retval.ui;
91 	} else
92 		return value;
93 }
94 
95 private uint32_t
96 getu32(int swap, uint32_t value)
97 {
98 	union {
99 		uint32_t ui;
100 		char c[4];
101 	} retval, tmpval;
102 
103 	if (swap) {
104 		tmpval.ui = value;
105 
106 		retval.c[0] = tmpval.c[3];
107 		retval.c[1] = tmpval.c[2];
108 		retval.c[2] = tmpval.c[1];
109 		retval.c[3] = tmpval.c[0];
110 
111 		return retval.ui;
112 	} else
113 		return value;
114 }
115 
116 private uint64_t
117 getu64(int swap, uint64_t value)
118 {
119 	union {
120 		uint64_t ui;
121 		char c[8];
122 	} retval, tmpval;
123 
124 	if (swap) {
125 		tmpval.ui = value;
126 
127 		retval.c[0] = tmpval.c[7];
128 		retval.c[1] = tmpval.c[6];
129 		retval.c[2] = tmpval.c[5];
130 		retval.c[3] = tmpval.c[4];
131 		retval.c[4] = tmpval.c[3];
132 		retval.c[5] = tmpval.c[2];
133 		retval.c[6] = tmpval.c[1];
134 		retval.c[7] = tmpval.c[0];
135 
136 		return retval.ui;
137 	} else
138 		return value;
139 }
140 
141 #define elf_getu16(swap, value) getu16(swap, value)
142 #define elf_getu32(swap, value) getu32(swap, value)
143 #define elf_getu64(swap, value) getu64(swap, value)
144 
145 #define xsh_addr	(clazz == ELFCLASS32			\
146 			 ? (void *)&sh32			\
147 			 : (void *)&sh64)
148 #define xsh_sizeof	(clazz == ELFCLASS32			\
149 			 ? sizeof(sh32)				\
150 			 : sizeof(sh64))
151 #define xsh_size	(size_t)(clazz == ELFCLASS32		\
152 			 ? elf_getu32(swap, sh32.sh_size)	\
153 			 : elf_getu64(swap, sh64.sh_size))
154 #define xsh_offset	(off_t)(clazz == ELFCLASS32		\
155 			 ? elf_getu32(swap, sh32.sh_offset)	\
156 			 : elf_getu64(swap, sh64.sh_offset))
157 #define xsh_type	(clazz == ELFCLASS32			\
158 			 ? elf_getu32(swap, sh32.sh_type)	\
159 			 : elf_getu32(swap, sh64.sh_type))
160 #define xsh_name    	(clazz == ELFCLASS32			\
161 			 ? elf_getu32(swap, sh32.sh_name)	\
162 			 : elf_getu32(swap, sh64.sh_name))
163 #define xph_addr	(clazz == ELFCLASS32			\
164 			 ? (void *) &ph32			\
165 			 : (void *) &ph64)
166 #define xph_sizeof	(clazz == ELFCLASS32			\
167 			 ? sizeof(ph32)				\
168 			 : sizeof(ph64))
169 #define xph_type	(clazz == ELFCLASS32			\
170 			 ? elf_getu32(swap, ph32.p_type)	\
171 			 : elf_getu32(swap, ph64.p_type))
172 #define xph_offset	(off_t)(clazz == ELFCLASS32		\
173 			 ? elf_getu32(swap, ph32.p_offset)	\
174 			 : elf_getu64(swap, ph64.p_offset))
175 #define xph_align	(size_t)((clazz == ELFCLASS32		\
176 			 ? (off_t) (ph32.p_align ? 		\
177 			    elf_getu32(swap, ph32.p_align) : 4) \
178 			 : (off_t) (ph64.p_align ?		\
179 			    elf_getu64(swap, ph64.p_align) : 4)))
180 #define xph_filesz	(size_t)((clazz == ELFCLASS32		\
181 			 ? elf_getu32(swap, ph32.p_filesz)	\
182 			 : elf_getu64(swap, ph64.p_filesz)))
183 #define xnh_addr	(clazz == ELFCLASS32			\
184 			 ? (void *)&nh32			\
185 			 : (void *)&nh64)
186 #define xph_memsz	(size_t)((clazz == ELFCLASS32		\
187 			 ? elf_getu32(swap, ph32.p_memsz)	\
188 			 : elf_getu64(swap, ph64.p_memsz)))
189 #define xnh_sizeof	(clazz == ELFCLASS32			\
190 			 ? sizeof nh32				\
191 			 : sizeof nh64)
192 #define xnh_type	(clazz == ELFCLASS32			\
193 			 ? elf_getu32(swap, nh32.n_type)	\
194 			 : elf_getu32(swap, nh64.n_type))
195 #define xnh_namesz	(clazz == ELFCLASS32			\
196 			 ? elf_getu32(swap, nh32.n_namesz)	\
197 			 : elf_getu32(swap, nh64.n_namesz))
198 #define xnh_descsz	(clazz == ELFCLASS32			\
199 			 ? elf_getu32(swap, nh32.n_descsz)	\
200 			 : elf_getu32(swap, nh64.n_descsz))
201 #define prpsoffsets(i)	(clazz == ELFCLASS32			\
202 			 ? prpsoffsets32[i]			\
203 			 : prpsoffsets64[i])
204 #define xcap_addr	(clazz == ELFCLASS32			\
205 			 ? (void *)&cap32			\
206 			 : (void *)&cap64)
207 #define xcap_sizeof	(clazz == ELFCLASS32			\
208 			 ? sizeof cap32				\
209 			 : sizeof cap64)
210 #define xcap_tag	(clazz == ELFCLASS32			\
211 			 ? elf_getu32(swap, cap32.c_tag)	\
212 			 : elf_getu64(swap, cap64.c_tag))
213 #define xcap_val	(clazz == ELFCLASS32			\
214 			 ? elf_getu32(swap, cap32.c_un.c_val)	\
215 			 : elf_getu64(swap, cap64.c_un.c_val))
216 
217 #ifdef ELFCORE
218 /*
219  * Try larger offsets first to avoid false matches
220  * from earlier data that happen to look like strings.
221  */
222 static const size_t	prpsoffsets32[] = {
223 #ifdef USE_NT_PSINFO
224 	104,		/* SunOS 5.x (command line) */
225 	88,		/* SunOS 5.x (short name) */
226 #endif /* USE_NT_PSINFO */
227 
228 	100,		/* SunOS 5.x (command line) */
229 	84,		/* SunOS 5.x (short name) */
230 
231 	44,		/* Linux (command line) */
232 	28,		/* Linux 2.0.36 (short name) */
233 
234 	8,		/* FreeBSD */
235 };
236 
237 static const size_t	prpsoffsets64[] = {
238 #ifdef USE_NT_PSINFO
239 	152,		/* SunOS 5.x (command line) */
240 	136,		/* SunOS 5.x (short name) */
241 #endif /* USE_NT_PSINFO */
242 
243 	136,		/* SunOS 5.x, 64-bit (command line) */
244 	120,		/* SunOS 5.x, 64-bit (short name) */
245 
246 	56,		/* Linux (command line) */
247 	40,             /* Linux (tested on core from 2.4.x, short name) */
248 
249 	16,		/* FreeBSD, 64-bit */
250 };
251 
252 #define	NOFFSETS32	(sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
253 #define NOFFSETS64	(sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
254 
255 #define NOFFSETS	(clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
256 
257 /*
258  * Look through the program headers of an executable image, searching
259  * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
260  * "FreeBSD"; if one is found, try looking in various places in its
261  * contents for a 16-character string containing only printable
262  * characters - if found, that string should be the name of the program
263  * that dropped core.  Note: right after that 16-character string is,
264  * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
265  * Linux, a longer string (80 characters, in 5.x, probably other
266  * SVR4-flavored systems, and Linux) containing the start of the
267  * command line for that program.
268  *
269  * SunOS 5.x core files contain two PT_NOTE sections, with the types
270  * NT_PRPSINFO (old) and NT_PSINFO (new).  These structs contain the
271  * same info about the command name and command line, so it probably
272  * isn't worthwhile to look for NT_PSINFO, but the offsets are provided
273  * above (see USE_NT_PSINFO), in case we ever decide to do so.  The
274  * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent;
275  * the SunOS 5.x file command relies on this (and prefers the latter).
276  *
277  * The signal number probably appears in a section of type NT_PRSTATUS,
278  * but that's also rather OS-dependent, in ways that are harder to
279  * dissect with heuristics, so I'm not bothering with the signal number.
280  * (I suppose the signal number could be of interest in situations where
281  * you don't have the binary of the program that dropped core; if you
282  * *do* have that binary, the debugger will probably tell you what
283  * signal it was.)
284  */
285 
286 #define	OS_STYLE_SVR4		0
287 #define	OS_STYLE_FREEBSD	1
288 #define	OS_STYLE_NETBSD		2
289 
290 private const char os_style_names[][8] = {
291 	"SVR4",
292 	"FreeBSD",
293 	"NetBSD",
294 };
295 
296 #define FLAGS_DID_CORE			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 
306 private int
307 dophn_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 
364 static void
365 do_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 
409 static void
410 do_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 
484 private int
485 /*ARGSUSED*/
486 do_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 
507 private int
508 do_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 
599 private int
600 do_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 
637 private int
638 do_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 
816 private size_t
817 donote(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 */
940 typedef struct cap_desc {
941 	uint64_t cd_mask;
942 	const char *cd_name;
943 } cap_desc_t;
944 
945 static 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 
960 static 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 
989 private int
990 doshn(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 		/* Things we can determine when we seek */
1052 		switch (xsh_type) {
1053 		case SHT_NOTE:
1054 			if ((nbuf = malloc(xsh_size)) == NULL) {
1055 				file_error(ms, errno, "Cannot allocate memory"
1056 				    " for note");
1057 				return -1;
1058 			}
1059 			if (pread(fd, nbuf, xsh_size, xsh_offset) < (ssize_t)xsh_size) {
1060 				file_badread(ms);
1061 				free(nbuf);
1062 				return -1;
1063 			}
1064 
1065 			noff = 0;
1066 			for (;;) {
1067 				if (noff >= (off_t)xsh_size)
1068 					break;
1069 				noff = donote(ms, nbuf, (size_t)noff,
1070 				    xsh_size, clazz, swap, 4, flags, notecount);
1071 				if (noff == 0)
1072 					break;
1073 			}
1074 			free(nbuf);
1075 			break;
1076 		case SHT_SUNW_cap:
1077 			switch (mach) {
1078 			case EM_SPARC:
1079 			case EM_SPARCV9:
1080 			case EM_IA_64:
1081 			case EM_386:
1082 			case EM_AMD64:
1083 				break;
1084 			default:
1085 				goto skip;
1086 			}
1087 
1088 			if (nbadcap > 5)
1089 				break;
1090 			if (lseek(fd, xsh_offset, SEEK_SET) == (off_t)-1) {
1091 				file_badseek(ms);
1092 				return -1;
1093 			}
1094 			coff = 0;
1095 			for (;;) {
1096 				Elf32_Cap cap32;
1097 				Elf64_Cap cap64;
1098 				char cbuf[/*CONSTCOND*/
1099 				    MAX(sizeof cap32, sizeof cap64)];
1100 				if ((coff += xcap_sizeof) > (off_t)xsh_size)
1101 					break;
1102 				if (read(fd, cbuf, (size_t)xcap_sizeof) !=
1103 				    (ssize_t)xcap_sizeof) {
1104 					file_badread(ms);
1105 					return -1;
1106 				}
1107 				if (cbuf[0] == 'A') {
1108 #ifdef notyet
1109 					char *p = cbuf + 1;
1110 					uint32_t len, tag;
1111 					memcpy(&len, p, sizeof(len));
1112 					p += 4;
1113 					len = getu32(swap, len);
1114 					if (memcmp("gnu", p, 3) != 0) {
1115 					    if (file_printf(ms,
1116 						", unknown capability %.3s", p)
1117 						== -1)
1118 						return -1;
1119 					    break;
1120 					}
1121 					p += strlen(p) + 1;
1122 					tag = *p++;
1123 					memcpy(&len, p, sizeof(len));
1124 					p += 4;
1125 					len = getu32(swap, len);
1126 					if (tag != 1) {
1127 					    if (file_printf(ms, ", unknown gnu"
1128 						" capability tag %d", tag)
1129 						== -1)
1130 						return -1;
1131 					    break;
1132 					}
1133 					// gnu attributes
1134 #endif
1135 					break;
1136 				}
1137 				(void)memcpy(xcap_addr, cbuf, xcap_sizeof);
1138 				switch (xcap_tag) {
1139 				case CA_SUNW_NULL:
1140 					break;
1141 				case CA_SUNW_HW_1:
1142 					cap_hw1 |= xcap_val;
1143 					break;
1144 				case CA_SUNW_SF_1:
1145 					cap_sf1 |= xcap_val;
1146 					break;
1147 				default:
1148 					if (file_printf(ms,
1149 					    ", with unknown capability "
1150 					    "0x%" INT64_T_FORMAT "x = 0x%"
1151 					    INT64_T_FORMAT "x",
1152 					    (unsigned long long)xcap_tag,
1153 					    (unsigned long long)xcap_val) == -1)
1154 						return -1;
1155 					if (nbadcap++ > 2)
1156 						coff = xsh_size;
1157 					break;
1158 				}
1159 			}
1160 			/*FALLTHROUGH*/
1161 		skip:
1162 		default:
1163 			break;
1164 		}
1165 	}
1166 
1167 	if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1)
1168 		return -1;
1169 	if (cap_hw1) {
1170 		const cap_desc_t *cdp;
1171 		switch (mach) {
1172 		case EM_SPARC:
1173 		case EM_SPARC32PLUS:
1174 		case EM_SPARCV9:
1175 			cdp = cap_desc_sparc;
1176 			break;
1177 		case EM_386:
1178 		case EM_IA_64:
1179 		case EM_AMD64:
1180 			cdp = cap_desc_386;
1181 			break;
1182 		default:
1183 			cdp = NULL;
1184 			break;
1185 		}
1186 		if (file_printf(ms, ", uses") == -1)
1187 			return -1;
1188 		if (cdp) {
1189 			while (cdp->cd_name) {
1190 				if (cap_hw1 & cdp->cd_mask) {
1191 					if (file_printf(ms,
1192 					    " %s", cdp->cd_name) == -1)
1193 						return -1;
1194 					cap_hw1 &= ~cdp->cd_mask;
1195 				}
1196 				++cdp;
1197 			}
1198 			if (cap_hw1)
1199 				if (file_printf(ms,
1200 				    " unknown hardware capability 0x%"
1201 				    INT64_T_FORMAT "x",
1202 				    (unsigned long long)cap_hw1) == -1)
1203 					return -1;
1204 		} else {
1205 			if (file_printf(ms,
1206 			    " hardware capability 0x%" INT64_T_FORMAT "x",
1207 			    (unsigned long long)cap_hw1) == -1)
1208 				return -1;
1209 		}
1210 	}
1211 	if (cap_sf1) {
1212 		if (cap_sf1 & SF1_SUNW_FPUSED) {
1213 			if (file_printf(ms,
1214 			    (cap_sf1 & SF1_SUNW_FPKNWN)
1215 			    ? ", uses frame pointer"
1216 			    : ", not known to use frame pointer") == -1)
1217 				return -1;
1218 		}
1219 		cap_sf1 &= ~SF1_SUNW_MASK;
1220 		if (cap_sf1)
1221 			if (file_printf(ms,
1222 			    ", with unknown software capability 0x%"
1223 			    INT64_T_FORMAT "x",
1224 			    (unsigned long long)cap_sf1) == -1)
1225 				return -1;
1226 	}
1227 	return 0;
1228 }
1229 
1230 /*
1231  * Look through the program headers of an executable image, searching
1232  * for a PT_INTERP section; if one is found, it's dynamically linked,
1233  * otherwise it's statically linked.
1234  */
1235 private int
1236 dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
1237     int num, size_t size, off_t fsize, int sh_num, int *flags,
1238     uint16_t *notecount)
1239 {
1240 	Elf32_Phdr ph32;
1241 	Elf64_Phdr ph64;
1242 	const char *linking_style = "statically";
1243 	const char *interp = "";
1244 	unsigned char nbuf[BUFSIZ];
1245 	char ibuf[BUFSIZ];
1246 	ssize_t bufsize;
1247 	size_t offset, align, len;
1248 
1249 	if (size != xph_sizeof) {
1250 		if (file_printf(ms, ", corrupted program header size") == -1)
1251 			return -1;
1252 		return 0;
1253 	}
1254 
1255   	for ( ; num; num--) {
1256 		if (pread(fd, xph_addr, xph_sizeof, off) < (ssize_t)xph_sizeof) {
1257 			file_badread(ms);
1258 			return -1;
1259 		}
1260 
1261 		off += size;
1262 		bufsize = 0;
1263 		align = 4;
1264 
1265 		/* Things we can determine before we seek */
1266 		switch (xph_type) {
1267 		case PT_DYNAMIC:
1268 			linking_style = "dynamically";
1269 			break;
1270 		case PT_NOTE:
1271 			if (sh_num)	/* Did this through section headers */
1272 				continue;
1273 			if (((align = xph_align) & 0x80000000UL) != 0 ||
1274 			    align < 4) {
1275 				if (file_printf(ms,
1276 				    ", invalid note alignment 0x%lx",
1277 				    (unsigned long)align) == -1)
1278 					return -1;
1279 				align = 4;
1280 			}
1281 			/*FALLTHROUGH*/
1282 		case PT_INTERP:
1283 			len = xph_filesz < sizeof(nbuf) ? xph_filesz
1284 			    : sizeof(nbuf);
1285 			bufsize = pread(fd, nbuf, len, xph_offset);
1286 			if (bufsize == -1) {
1287 				file_badread(ms);
1288 				return -1;
1289 			}
1290 			break;
1291 		default:
1292 			if (fsize != SIZE_UNKNOWN && xph_offset > fsize) {
1293 				/* Maybe warn here? */
1294 				continue;
1295 			}
1296 			break;
1297 		}
1298 
1299 		/* Things we can determine when we seek */
1300 		switch (xph_type) {
1301 		case PT_INTERP:
1302 			if (bufsize && nbuf[0]) {
1303 				nbuf[bufsize - 1] = '\0';
1304 				interp = (const char *)nbuf;
1305 			} else
1306 				interp = "*empty*";
1307 			break;
1308 		case PT_NOTE:
1309 			/*
1310 			 * This is a PT_NOTE section; loop through all the notes
1311 			 * in the section.
1312 			 */
1313 			offset = 0;
1314 			for (;;) {
1315 				if (offset >= (size_t)bufsize)
1316 					break;
1317 				offset = donote(ms, nbuf, offset,
1318 				    (size_t)bufsize, clazz, swap, align,
1319 				    flags, notecount);
1320 				if (offset == 0)
1321 					break;
1322 			}
1323 			break;
1324 		default:
1325 			break;
1326 		}
1327 	}
1328 	if (file_printf(ms, ", %s linked", linking_style)
1329 	    == -1)
1330 		return -1;
1331 	if (interp[0])
1332 		if (file_printf(ms, ", interpreter %s",
1333 		    file_printable(ibuf, sizeof(ibuf), interp)) == -1)
1334 			return -1;
1335 	return 0;
1336 }
1337 
1338 
1339 protected int
1340 file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
1341     size_t nbytes)
1342 {
1343 	union {
1344 		int32_t l;
1345 		char c[sizeof (int32_t)];
1346 	} u;
1347 	int clazz;
1348 	int swap;
1349 	struct stat st;
1350 	off_t fsize;
1351 	int flags = 0;
1352 	Elf32_Ehdr elf32hdr;
1353 	Elf64_Ehdr elf64hdr;
1354 	uint16_t type, phnum, shnum, notecount;
1355 
1356 	if (ms->flags & (MAGIC_MIME|MAGIC_APPLE|MAGIC_EXTENSION))
1357 		return 0;
1358 	/*
1359 	 * ELF executables have multiple section headers in arbitrary
1360 	 * file locations and thus file(1) cannot determine it from easily.
1361 	 * Instead we traverse thru all section headers until a symbol table
1362 	 * one is found or else the binary is stripped.
1363 	 * Return immediately if it's not ELF (so we avoid pipe2file unless needed).
1364 	 */
1365 	if (buf[EI_MAG0] != ELFMAG0
1366 	    || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
1367 	    || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
1368 		return 0;
1369 
1370 	/*
1371 	 * If we cannot seek, it must be a pipe, socket or fifo.
1372 	 */
1373 	if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE))
1374 		fd = file_pipe2file(ms, fd, buf, nbytes);
1375 
1376 	if (fstat(fd, &st) == -1) {
1377   		file_badread(ms);
1378 		return -1;
1379 	}
1380 	if (S_ISREG(st.st_mode) || st.st_size != 0)
1381 		fsize = st.st_size;
1382 	else
1383 		fsize = SIZE_UNKNOWN;
1384 
1385 	clazz = buf[EI_CLASS];
1386 
1387 	switch (clazz) {
1388 	case ELFCLASS32:
1389 #undef elf_getu
1390 #define elf_getu(a, b)	elf_getu32(a, b)
1391 #undef elfhdr
1392 #define elfhdr elf32hdr
1393 #include "elfclass.h"
1394 	case ELFCLASS64:
1395 #undef elf_getu
1396 #define elf_getu(a, b)	elf_getu64(a, b)
1397 #undef elfhdr
1398 #define elfhdr elf64hdr
1399 #include "elfclass.h"
1400 	default:
1401 	    if (file_printf(ms, ", unknown class %d", clazz) == -1)
1402 		    return -1;
1403 	    break;
1404 	}
1405 	return 0;
1406 }
1407 #endif
1408