xref: /dragonfly/contrib/file/src/readelf.c (revision a444603f)
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 1.173 2020/06/07 22:12:54 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 *, int, off_t, int, off_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	CAST(off_t, -1)
66 
67 private int
68 toomany(struct magic_set *ms, const char *name, uint16_t num)
69 {
70 	if (ms->flags & MAGIC_MIME)
71 		return 1;
72 	if (file_printf(ms, ", too many %s (%u)", name, num) == -1)
73 		return -1;
74 	return 1;
75 }
76 
77 private uint16_t
78 getu16(int swap, uint16_t value)
79 {
80 	union {
81 		uint16_t ui;
82 		char c[2];
83 	} retval, tmpval;
84 
85 	if (swap) {
86 		tmpval.ui = value;
87 
88 		retval.c[0] = tmpval.c[1];
89 		retval.c[1] = tmpval.c[0];
90 
91 		return retval.ui;
92 	} else
93 		return value;
94 }
95 
96 private uint32_t
97 getu32(int swap, uint32_t value)
98 {
99 	union {
100 		uint32_t ui;
101 		char c[4];
102 	} retval, tmpval;
103 
104 	if (swap) {
105 		tmpval.ui = value;
106 
107 		retval.c[0] = tmpval.c[3];
108 		retval.c[1] = tmpval.c[2];
109 		retval.c[2] = tmpval.c[1];
110 		retval.c[3] = tmpval.c[0];
111 
112 		return retval.ui;
113 	} else
114 		return value;
115 }
116 
117 private uint64_t
118 getu64(int swap, uint64_t value)
119 {
120 	union {
121 		uint64_t ui;
122 		char c[8];
123 	} retval, tmpval;
124 
125 	if (swap) {
126 		tmpval.ui = value;
127 
128 		retval.c[0] = tmpval.c[7];
129 		retval.c[1] = tmpval.c[6];
130 		retval.c[2] = tmpval.c[5];
131 		retval.c[3] = tmpval.c[4];
132 		retval.c[4] = tmpval.c[3];
133 		retval.c[5] = tmpval.c[2];
134 		retval.c[6] = tmpval.c[1];
135 		retval.c[7] = tmpval.c[0];
136 
137 		return retval.ui;
138 	} else
139 		return value;
140 }
141 
142 #define elf_getu16(swap, value) getu16(swap, value)
143 #define elf_getu32(swap, value) getu32(swap, value)
144 #define elf_getu64(swap, value) getu64(swap, value)
145 
146 #define xsh_addr	(clazz == ELFCLASS32			\
147 			 ? CAST(void *, &sh32)			\
148 			 : CAST(void *, &sh64))
149 #define xsh_sizeof	(clazz == ELFCLASS32			\
150 			 ? sizeof(sh32)				\
151 			 : sizeof(sh64))
152 #define xsh_size	CAST(size_t, (clazz == ELFCLASS32	\
153 			 ? elf_getu32(swap, sh32.sh_size)	\
154 			 : elf_getu64(swap, sh64.sh_size)))
155 #define xsh_offset	CAST(off_t, (clazz == ELFCLASS32	\
156 			 ? elf_getu32(swap, sh32.sh_offset)	\
157 			 : elf_getu64(swap, sh64.sh_offset)))
158 #define xsh_type	(clazz == ELFCLASS32			\
159 			 ? elf_getu32(swap, sh32.sh_type)	\
160 			 : elf_getu32(swap, sh64.sh_type))
161 #define xsh_name    	(clazz == ELFCLASS32			\
162 			 ? elf_getu32(swap, sh32.sh_name)	\
163 			 : elf_getu32(swap, sh64.sh_name))
164 
165 #define xph_addr	(clazz == ELFCLASS32			\
166 			 ? CAST(void *, &ph32)			\
167 			 : CAST(void *, &ph64))
168 #define xph_sizeof	(clazz == ELFCLASS32			\
169 			 ? sizeof(ph32)				\
170 			 : sizeof(ph64))
171 #define xph_type	(clazz == ELFCLASS32			\
172 			 ? elf_getu32(swap, ph32.p_type)	\
173 			 : elf_getu32(swap, ph64.p_type))
174 #define xph_offset	CAST(off_t, (clazz == ELFCLASS32	\
175 			 ? elf_getu32(swap, ph32.p_offset)	\
176 			 : elf_getu64(swap, ph64.p_offset)))
177 #define xph_align	CAST(size_t, (clazz == ELFCLASS32	\
178 			 ? CAST(off_t, (ph32.p_align ? 		\
179 			    elf_getu32(swap, ph32.p_align) : 4))\
180 			 : CAST(off_t, (ph64.p_align ?		\
181 			    elf_getu64(swap, ph64.p_align) : 4))))
182 #define xph_vaddr	CAST(size_t, (clazz == ELFCLASS32	\
183 			 ? CAST(off_t, (ph32.p_vaddr ? 		\
184 			    elf_getu32(swap, ph32.p_vaddr) : 4))\
185 			 : CAST(off_t, (ph64.p_vaddr ?		\
186 			    elf_getu64(swap, ph64.p_vaddr) : 4))))
187 #define xph_filesz	CAST(size_t, (clazz == ELFCLASS32	\
188 			 ? elf_getu32(swap, ph32.p_filesz)	\
189 			 : elf_getu64(swap, ph64.p_filesz)))
190 #define xph_memsz	CAST(size_t, ((clazz == ELFCLASS32	\
191 			 ? elf_getu32(swap, ph32.p_memsz)	\
192 			 : elf_getu64(swap, ph64.p_memsz))))
193 #define xnh_addr	(clazz == ELFCLASS32			\
194 			 ? CAST(void *, &nh32)			\
195 			 : CAST(void *, &nh64))
196 #define xnh_sizeof	(clazz == ELFCLASS32			\
197 			 ? sizeof(nh32)				\
198 			 : sizeof(nh64))
199 #define xnh_type	(clazz == ELFCLASS32			\
200 			 ? elf_getu32(swap, nh32.n_type)	\
201 			 : elf_getu32(swap, nh64.n_type))
202 #define xnh_namesz	(clazz == ELFCLASS32			\
203 			 ? elf_getu32(swap, nh32.n_namesz)	\
204 			 : elf_getu32(swap, nh64.n_namesz))
205 #define xnh_descsz	(clazz == ELFCLASS32			\
206 			 ? elf_getu32(swap, nh32.n_descsz)	\
207 			 : elf_getu32(swap, nh64.n_descsz))
208 
209 #define xdh_addr	(clazz == ELFCLASS32			\
210 			 ? CAST(void *, &dh32)			\
211 			 : CAST(void *, &dh64))
212 #define xdh_sizeof	(clazz == ELFCLASS32			\
213 			 ? sizeof(dh32)				\
214 			 : sizeof(dh64))
215 #define xdh_tag		(clazz == ELFCLASS32			\
216 			 ? elf_getu32(swap, dh32.d_tag)		\
217 			 : elf_getu64(swap, dh64.d_tag))
218 #define xdh_val		(clazz == ELFCLASS32			\
219 			 ? elf_getu32(swap, dh32.d_un.d_val)	\
220 			 : elf_getu64(swap, dh64.d_un.d_val))
221 
222 #define xcap_addr	(clazz == ELFCLASS32			\
223 			 ? CAST(void *, &cap32)			\
224 			 : CAST(void *, &cap64))
225 #define xcap_sizeof	(clazz == ELFCLASS32			\
226 			 ? sizeof(cap32)			\
227 			 : sizeof(cap64))
228 #define xcap_tag	(clazz == ELFCLASS32			\
229 			 ? elf_getu32(swap, cap32.c_tag)	\
230 			 : elf_getu64(swap, cap64.c_tag))
231 #define xcap_val	(clazz == ELFCLASS32			\
232 			 ? elf_getu32(swap, cap32.c_un.c_val)	\
233 			 : elf_getu64(swap, cap64.c_un.c_val))
234 
235 #define xauxv_addr	(clazz == ELFCLASS32			\
236 			 ? CAST(void *, &auxv32)		\
237 			 : CAST(void *, &auxv64))
238 #define xauxv_sizeof	(clazz == ELFCLASS32			\
239 			 ? sizeof(auxv32)			\
240 			 : sizeof(auxv64))
241 #define xauxv_type	(clazz == ELFCLASS32			\
242 			 ? elf_getu32(swap, auxv32.a_type)	\
243 			 : elf_getu64(swap, auxv64.a_type))
244 #define xauxv_val	(clazz == ELFCLASS32			\
245 			 ? elf_getu32(swap, auxv32.a_v)		\
246 			 : elf_getu64(swap, auxv64.a_v))
247 
248 #define prpsoffsets(i)	(clazz == ELFCLASS32			\
249 			 ? prpsoffsets32[i]			\
250 			 : prpsoffsets64[i])
251 
252 #ifdef ELFCORE
253 /*
254  * Try larger offsets first to avoid false matches
255  * from earlier data that happen to look like strings.
256  */
257 static const size_t	prpsoffsets32[] = {
258 #ifdef USE_NT_PSINFO
259 	104,		/* SunOS 5.x (command line) */
260 	88,		/* SunOS 5.x (short name) */
261 #endif /* USE_NT_PSINFO */
262 
263 	100,		/* SunOS 5.x (command line) */
264 	84,		/* SunOS 5.x (short name) */
265 
266 	44,		/* Linux (command line) */
267 	28,		/* Linux (short name) */
268 
269 	48,		/* Linux PowerPC (command line) */
270 	32,		/* Linux PowerPC (short name) */
271 
272 	8,		/* FreeBSD */
273 };
274 
275 static const size_t	prpsoffsets64[] = {
276 #ifdef USE_NT_PSINFO
277 	152,		/* SunOS 5.x (command line) */
278 	136,		/* SunOS 5.x (short name) */
279 #endif /* USE_NT_PSINFO */
280 
281 	136,		/* SunOS 5.x, 64-bit (command line) */
282 	120,		/* SunOS 5.x, 64-bit (short name) */
283 
284 	56,		/* Linux (command line) */
285 	40,             /* Linux (tested on core from 2.4.x, short name) */
286 
287 	16,		/* FreeBSD, 64-bit */
288 };
289 
290 #define	NOFFSETS32	__arraycount(prpsoffsets32)
291 #define NOFFSETS64	__arraycount(prpsoffsets64)
292 
293 #define NOFFSETS	(clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
294 
295 /*
296  * Look through the program headers of an executable image, searching
297  * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
298  * "FreeBSD"; if one is found, try looking in various places in its
299  * contents for a 16-character string containing only printable
300  * characters - if found, that string should be the name of the program
301  * that dropped core.  Note: right after that 16-character string is,
302  * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
303  * Linux, a longer string (80 characters, in 5.x, probably other
304  * SVR4-flavored systems, and Linux) containing the start of the
305  * command line for that program.
306  *
307  * SunOS 5.x core files contain two PT_NOTE sections, with the types
308  * NT_PRPSINFO (old) and NT_PSINFO (new).  These structs contain the
309  * same info about the command name and command line, so it probably
310  * isn't worthwhile to look for NT_PSINFO, but the offsets are provided
311  * above (see USE_NT_PSINFO), in case we ever decide to do so.  The
312  * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent;
313  * the SunOS 5.x file command relies on this (and prefers the latter).
314  *
315  * The signal number probably appears in a section of type NT_PRSTATUS,
316  * but that's also rather OS-dependent, in ways that are harder to
317  * dissect with heuristics, so I'm not bothering with the signal number.
318  * (I suppose the signal number could be of interest in situations where
319  * you don't have the binary of the program that dropped core; if you
320  * *do* have that binary, the debugger will probably tell you what
321  * signal it was.)
322  */
323 
324 #define	OS_STYLE_SVR4		0
325 #define	OS_STYLE_FREEBSD	1
326 #define	OS_STYLE_NETBSD		2
327 
328 private const char os_style_names[][8] = {
329 	"SVR4",
330 	"FreeBSD",
331 	"NetBSD",
332 };
333 
334 #define FLAGS_CORE_STYLE		0x0003
335 
336 #define FLAGS_DID_CORE			0x0004
337 #define FLAGS_DID_OS_NOTE		0x0008
338 #define FLAGS_DID_BUILD_ID		0x0010
339 #define FLAGS_DID_CORE_STYLE		0x0020
340 #define FLAGS_DID_NETBSD_PAX		0x0040
341 #define FLAGS_DID_NETBSD_MARCH		0x0080
342 #define FLAGS_DID_NETBSD_CMODEL		0x0100
343 #define FLAGS_DID_NETBSD_EMULATION	0x0200
344 #define FLAGS_DID_NETBSD_UNKNOWN	0x0400
345 #define FLAGS_IS_CORE			0x0800
346 #define FLAGS_DID_AUXV			0x1000
347 
348 private int
349 dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
350     int num, size_t size, off_t fsize, int *flags, uint16_t *notecount)
351 {
352 	Elf32_Phdr ph32;
353 	Elf64_Phdr ph64;
354 	size_t offset, len;
355 	unsigned char nbuf[BUFSIZ];
356 	ssize_t bufsize;
357 	off_t ph_off = off;
358 	int ph_num = num;
359 
360 	if (ms->flags & MAGIC_MIME)
361 		return 0;
362 
363 	if (num == 0) {
364 		if (file_printf(ms, ", no program header") == -1)
365 			return -1;
366 		return 0;
367 	}
368 	if (size != xph_sizeof) {
369 		if (file_printf(ms, ", corrupted program header size") == -1)
370 			return -1;
371 		return 0;
372 	}
373 
374 	/*
375 	 * Loop through all the program headers.
376 	 */
377 	for ( ; num; num--) {
378 		if (pread(fd, xph_addr, xph_sizeof, off) <
379 		    CAST(ssize_t, xph_sizeof)) {
380 			file_badread(ms);
381 			return -1;
382 		}
383 		off += size;
384 
385 		if (fsize != SIZE_UNKNOWN && xph_offset > fsize) {
386 			/* Perhaps warn here */
387 			continue;
388 		}
389 
390 		if (xph_type != PT_NOTE)
391 			continue;
392 
393 		/*
394 		 * This is a PT_NOTE section; loop through all the notes
395 		 * in the section.
396 		 */
397 		len = xph_filesz < sizeof(nbuf) ? xph_filesz : sizeof(nbuf);
398 		if ((bufsize = pread(fd, nbuf, len, xph_offset)) == -1) {
399 			file_badread(ms);
400 			return -1;
401 		}
402 		offset = 0;
403 		for (;;) {
404 			if (offset >= CAST(size_t, bufsize))
405 				break;
406 			offset = donote(ms, nbuf, offset, CAST(size_t, bufsize),
407 			    clazz, swap, 4, flags, notecount, fd, ph_off,
408 			    ph_num, fsize);
409 			if (offset == 0)
410 				break;
411 
412 		}
413 	}
414 	return 0;
415 }
416 #endif
417 
418 static int
419 do_note_netbsd_version(struct magic_set *ms, int swap, void *v)
420 {
421 	uint32_t desc;
422 	memcpy(&desc, v, sizeof(desc));
423 	desc = elf_getu32(swap, desc);
424 
425 	if (file_printf(ms, ", for NetBSD") == -1)
426 		return -1;
427 	/*
428 	 * The version number used to be stuck as 199905, and was thus
429 	 * basically content-free.  Newer versions of NetBSD have fixed
430 	 * this and now use the encoding of __NetBSD_Version__:
431 	 *
432 	 *	MMmmrrpp00
433 	 *
434 	 * M = major version
435 	 * m = minor version
436 	 * r = release ["",A-Z,Z[A-Z] but numeric]
437 	 * p = patchlevel
438 	 */
439 	if (desc > 100000000U) {
440 		uint32_t ver_patch = (desc / 100) % 100;
441 		uint32_t ver_rel = (desc / 10000) % 100;
442 		uint32_t ver_min = (desc / 1000000) % 100;
443 		uint32_t ver_maj = desc / 100000000;
444 
445 		if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1)
446 			return -1;
447 		if (ver_rel == 0 && ver_patch != 0) {
448 			if (file_printf(ms, ".%u", ver_patch) == -1)
449 				return -1;
450 		} else if (ver_rel != 0) {
451 			while (ver_rel > 26) {
452 				if (file_printf(ms, "Z") == -1)
453 					return -1;
454 				ver_rel -= 26;
455 			}
456 			if (file_printf(ms, "%c", 'A' + ver_rel - 1)
457 			    == -1)
458 				return -1;
459 		}
460 	}
461 	return 0;
462 }
463 
464 static int
465 do_note_freebsd_version(struct magic_set *ms, int swap, void *v)
466 {
467 	uint32_t desc;
468 
469 	memcpy(&desc, v, sizeof(desc));
470 	desc = elf_getu32(swap, desc);
471 	if (file_printf(ms, ", for FreeBSD") == -1)
472 		return -1;
473 
474 	/*
475 	 * Contents is __FreeBSD_version, whose relation to OS
476 	 * versions is defined by a huge table in the Porter's
477 	 * Handbook.  This is the general scheme:
478 	 *
479 	 * Releases:
480 	 * 	Mmp000 (before 4.10)
481 	 * 	Mmi0p0 (before 5.0)
482 	 * 	Mmm0p0
483 	 *
484 	 * Development branches:
485 	 * 	Mmpxxx (before 4.6)
486 	 * 	Mmp1xx (before 4.10)
487 	 * 	Mmi1xx (before 5.0)
488 	 * 	M000xx (pre-M.0)
489 	 * 	Mmm1xx
490 	 *
491 	 * M = major version
492 	 * m = minor version
493 	 * i = minor version increment (491000 -> 4.10)
494 	 * p = patchlevel
495 	 * x = revision
496 	 *
497 	 * The first release of FreeBSD to use ELF by default
498 	 * was version 3.0.
499 	 */
500 	if (desc == 460002) {
501 		if (file_printf(ms, " 4.6.2") == -1)
502 			return -1;
503 	} else if (desc < 460100) {
504 		if (file_printf(ms, " %d.%d", desc / 100000,
505 		    desc / 10000 % 10) == -1)
506 			return -1;
507 		if (desc / 1000 % 10 > 0)
508 			if (file_printf(ms, ".%d", desc / 1000 % 10) == -1)
509 				return -1;
510 		if ((desc % 1000 > 0) || (desc % 100000 == 0))
511 			if (file_printf(ms, " (%d)", desc) == -1)
512 				return -1;
513 	} else if (desc < 500000) {
514 		if (file_printf(ms, " %d.%d", desc / 100000,
515 		    desc / 10000 % 10 + desc / 1000 % 10) == -1)
516 			return -1;
517 		if (desc / 100 % 10 > 0) {
518 			if (file_printf(ms, " (%d)", desc) == -1)
519 				return -1;
520 		} else if (desc / 10 % 10 > 0) {
521 			if (file_printf(ms, ".%d", desc / 10 % 10) == -1)
522 				return -1;
523 		}
524 	} else {
525 		if (file_printf(ms, " %d.%d", desc / 100000,
526 		    desc / 1000 % 100) == -1)
527 			return -1;
528 		if ((desc / 100 % 10 > 0) ||
529 		    (desc % 100000 / 100 == 0)) {
530 			if (file_printf(ms, " (%d)", desc) == -1)
531 				return -1;
532 		} else if (desc / 10 % 10 > 0) {
533 			if (file_printf(ms, ".%d", desc / 10 % 10) == -1)
534 				return -1;
535 		}
536 	}
537 	return 0;
538 }
539 
540 private int
541 /*ARGSUSED*/
542 do_bid_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type,
543     int swap __attribute__((__unused__)), uint32_t namesz, uint32_t descsz,
544     size_t noff, size_t doff, int *flags)
545 {
546 	if (namesz == 4 && strcmp(RCAST(char *, &nbuf[noff]), "GNU") == 0 &&
547 	    type == NT_GNU_BUILD_ID && (descsz >= 4 && descsz <= 20)) {
548 		uint8_t desc[20];
549 		const char *btype;
550 		uint32_t i;
551 		*flags |= FLAGS_DID_BUILD_ID;
552 		switch (descsz) {
553 		case 8:
554 		    btype = "xxHash";
555 		    break;
556 		case 16:
557 		    btype = "md5/uuid";
558 		    break;
559 		case 20:
560 		    btype = "sha1";
561 		    break;
562 		default:
563 		    btype = "unknown";
564 		    break;
565 		}
566 		if (file_printf(ms, ", BuildID[%s]=", btype) == -1)
567 			return -1;
568 		memcpy(desc, &nbuf[doff], descsz);
569 		for (i = 0; i < descsz; i++)
570 		    if (file_printf(ms, "%02x", desc[i]) == -1)
571 			return -1;
572 		return 1;
573 	}
574 	if (namesz == 4 && strcmp(RCAST(char *, &nbuf[noff]), "Go") == 0 &&
575 	    type == NT_GO_BUILD_ID && descsz < 128) {
576 		char buf[256];
577 		if (file_printf(ms, ", Go BuildID=%s",
578 		    file_copystr(buf, sizeof(buf), descsz,
579 		    RCAST(const char *, &nbuf[doff]))) == -1)
580 			return -1;
581 		return 1;
582 	}
583 	return 0;
584 }
585 
586 private int
587 do_os_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type,
588     int swap, uint32_t namesz, uint32_t descsz,
589     size_t noff, size_t doff, int *flags)
590 {
591 	const char *name = RCAST(const char *, &nbuf[noff]);
592 
593 	if (namesz == 5 && strcmp(name, "SuSE") == 0 &&
594 		type == NT_GNU_VERSION && descsz == 2) {
595 		*flags |= FLAGS_DID_OS_NOTE;
596 		if (file_printf(ms, ", for SuSE %d.%d", nbuf[doff],
597 		    nbuf[doff + 1]) == -1)
598 		    return -1;
599 	    return 1;
600 	}
601 
602 	if (namesz == 4 && strcmp(name, "GNU") == 0 &&
603 	    type == NT_GNU_VERSION && descsz == 16) {
604 		uint32_t desc[4];
605 		memcpy(desc, &nbuf[doff], sizeof(desc));
606 
607 		*flags |= FLAGS_DID_OS_NOTE;
608 		if (file_printf(ms, ", for GNU/") == -1)
609 			return -1;
610 		switch (elf_getu32(swap, desc[0])) {
611 		case GNU_OS_LINUX:
612 			if (file_printf(ms, "Linux") == -1)
613 				return -1;
614 			break;
615 		case GNU_OS_HURD:
616 			if (file_printf(ms, "Hurd") == -1)
617 				return -1;
618 			break;
619 		case GNU_OS_SOLARIS:
620 			if (file_printf(ms, "Solaris") == -1)
621 				return -1;
622 			break;
623 		case GNU_OS_KFREEBSD:
624 			if (file_printf(ms, "kFreeBSD") == -1)
625 				return -1;
626 			break;
627 		case GNU_OS_KNETBSD:
628 			if (file_printf(ms, "kNetBSD") == -1)
629 				return -1;
630 			break;
631 		default:
632 			if (file_printf(ms, "<unknown>") == -1)
633 				return -1;
634 		}
635 		if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]),
636 		    elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1)
637 			return -1;
638 		return 1;
639 	}
640 
641 	if (namesz == 7 && strcmp(name, "NetBSD") == 0) {
642 	    	if (type == NT_NETBSD_VERSION && descsz == 4) {
643 			*flags |= FLAGS_DID_OS_NOTE;
644 			if (do_note_netbsd_version(ms, swap, &nbuf[doff]) == -1)
645 				return -1;
646 			return 1;
647 		}
648 	}
649 
650 	if (namesz == 8 && strcmp(name, "FreeBSD") == 0) {
651 	    	if (type == NT_FREEBSD_VERSION && descsz == 4) {
652 			*flags |= FLAGS_DID_OS_NOTE;
653 			if (do_note_freebsd_version(ms, swap, &nbuf[doff])
654 			    == -1)
655 				return -1;
656 			return 1;
657 		}
658 	}
659 
660 	if (namesz == 8 && strcmp(name, "OpenBSD") == 0 &&
661 	    type == NT_OPENBSD_VERSION && descsz == 4) {
662 		*flags |= FLAGS_DID_OS_NOTE;
663 		if (file_printf(ms, ", for OpenBSD") == -1)
664 			return -1;
665 		/* Content of note is always 0 */
666 		return 1;
667 	}
668 
669 	if (namesz == 10 && strcmp(name, "DragonFly") == 0 &&
670 	    type == NT_DRAGONFLY_VERSION && descsz == 4) {
671 		uint32_t desc;
672 		*flags |= FLAGS_DID_OS_NOTE;
673 		if (file_printf(ms, ", for DragonFly") == -1)
674 			return -1;
675 		memcpy(&desc, &nbuf[doff], sizeof(desc));
676 		desc = elf_getu32(swap, desc);
677 		if (file_printf(ms, " %d.%d.%d", desc / 100000,
678 		    desc / 10000 % 10, desc % 10000) == -1)
679 			return -1;
680 		return 1;
681 	}
682 	return 0;
683 }
684 
685 private int
686 do_pax_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type,
687     int swap, uint32_t namesz, uint32_t descsz,
688     size_t noff, size_t doff, int *flags)
689 {
690 	const char *name = RCAST(const char *, &nbuf[noff]);
691 
692 	if (namesz == 4 && strcmp(name, "PaX") == 0 &&
693 	    type == NT_NETBSD_PAX && descsz == 4) {
694 		static const char *pax[] = {
695 		    "+mprotect",
696 		    "-mprotect",
697 		    "+segvguard",
698 		    "-segvguard",
699 		    "+ASLR",
700 		    "-ASLR",
701 		};
702 		uint32_t desc;
703 		size_t i;
704 		int did = 0;
705 
706 		*flags |= FLAGS_DID_NETBSD_PAX;
707 		memcpy(&desc, &nbuf[doff], sizeof(desc));
708 		desc = elf_getu32(swap, desc);
709 
710 		if (desc && file_printf(ms, ", PaX: ") == -1)
711 			return -1;
712 
713 		for (i = 0; i < __arraycount(pax); i++) {
714 			if (((1 << CAST(int, i)) & desc) == 0)
715 				continue;
716 			if (file_printf(ms, "%s%s", did++ ? "," : "",
717 			    pax[i]) == -1)
718 				return -1;
719 		}
720 		return 1;
721 	}
722 	return 0;
723 }
724 
725 private int
726 do_core_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type,
727     int swap, uint32_t namesz, uint32_t descsz,
728     size_t noff, size_t doff, int *flags, size_t size, int clazz)
729 {
730 #ifdef ELFCORE
731 	char buf[256];
732 	const char *name = RCAST(const char *, &nbuf[noff]);
733 
734 	int os_style = -1;
735 	/*
736 	 * Sigh.  The 2.0.36 kernel in Debian 2.1, at
737 	 * least, doesn't correctly implement name
738 	 * sections, in core dumps, as specified by
739 	 * the "Program Linking" section of "UNIX(R) System
740 	 * V Release 4 Programmer's Guide: ANSI C and
741 	 * Programming Support Tools", because my copy
742 	 * clearly says "The first 'namesz' bytes in 'name'
743 	 * contain a *null-terminated* [emphasis mine]
744 	 * character representation of the entry's owner
745 	 * or originator", but the 2.0.36 kernel code
746 	 * doesn't include the terminating null in the
747 	 * name....
748 	 */
749 	if ((namesz == 4 && strncmp(name, "CORE", 4) == 0) ||
750 	    (namesz == 5 && strcmp(name, "CORE") == 0)) {
751 		os_style = OS_STYLE_SVR4;
752 	}
753 
754 	if ((namesz == 8 && strcmp(name, "FreeBSD") == 0)) {
755 		os_style = OS_STYLE_FREEBSD;
756 	}
757 
758 	if ((namesz >= 11 && strncmp(name, "NetBSD-CORE", 11)
759 	    == 0)) {
760 		os_style = OS_STYLE_NETBSD;
761 	}
762 
763 	if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) {
764 		if (file_printf(ms, ", %s-style", os_style_names[os_style])
765 		    == -1)
766 			return -1;
767 		*flags |= FLAGS_DID_CORE_STYLE;
768 		*flags |= os_style;
769 	}
770 
771 	switch (os_style) {
772 	case OS_STYLE_NETBSD:
773 		if (type == NT_NETBSD_CORE_PROCINFO) {
774 			char sbuf[512];
775 			struct NetBSD_elfcore_procinfo pi;
776 			memset(&pi, 0, sizeof(pi));
777 			memcpy(&pi, nbuf + doff, MIN(descsz, sizeof(pi)));
778 
779 			if (file_printf(ms, ", from '%.31s', pid=%u, uid=%u, "
780 			    "gid=%u, nlwps=%u, lwp=%u (signal %u/code %u)",
781 			    file_printable(sbuf, sizeof(sbuf),
782 			    RCAST(char *, pi.cpi_name), sizeof(pi.cpi_name)),
783 			    elf_getu32(swap, CAST(uint32_t, pi.cpi_pid)),
784 			    elf_getu32(swap, pi.cpi_euid),
785 			    elf_getu32(swap, pi.cpi_egid),
786 			    elf_getu32(swap, pi.cpi_nlwps),
787 			    elf_getu32(swap, CAST(uint32_t, pi.cpi_siglwp)),
788 			    elf_getu32(swap, pi.cpi_signo),
789 			    elf_getu32(swap, pi.cpi_sigcode)) == -1)
790 				return -1;
791 
792 			*flags |= FLAGS_DID_CORE;
793 			return 1;
794 		}
795 		break;
796 
797 	case OS_STYLE_FREEBSD:
798 		if (type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) {
799 			size_t argoff, pidoff;
800 
801 			if (clazz == ELFCLASS32)
802 				argoff = 4 + 4 + 17;
803 			else
804 				argoff = 4 + 4 + 8 + 17;
805 			if (file_printf(ms, ", from '%.80s'", nbuf + doff +
806 			    argoff) == -1)
807 				return -1;
808 			pidoff = argoff + 81 + 2;
809 			if (doff + pidoff + 4 <= size) {
810 				if (file_printf(ms, ", pid=%u",
811 				    elf_getu32(swap, *RCAST(uint32_t *, (nbuf +
812 				    doff + pidoff)))) == -1)
813 					return -1;
814 			}
815 			*flags |= FLAGS_DID_CORE;
816 		}
817 		break;
818 
819 	default:
820 		if (type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) {
821 			size_t i, j;
822 			unsigned char c;
823 			/*
824 			 * Extract the program name.  We assume
825 			 * it to be 16 characters (that's what it
826 			 * is in SunOS 5.x and Linux).
827 			 *
828 			 * Unfortunately, it's at a different offset
829 			 * in various OSes, so try multiple offsets.
830 			 * If the characters aren't all printable,
831 			 * reject it.
832 			 */
833 			for (i = 0; i < NOFFSETS; i++) {
834 				unsigned char *cname, *cp;
835 				size_t reloffset = prpsoffsets(i);
836 				size_t noffset = doff + reloffset;
837 				size_t k;
838 				for (j = 0; j < 16; j++, noffset++,
839 				    reloffset++) {
840 					/*
841 					 * Make sure we're not past
842 					 * the end of the buffer; if
843 					 * we are, just give up.
844 					 */
845 					if (noffset >= size)
846 						goto tryanother;
847 
848 					/*
849 					 * Make sure we're not past
850 					 * the end of the contents;
851 					 * if we are, this obviously
852 					 * isn't the right offset.
853 					 */
854 					if (reloffset >= descsz)
855 						goto tryanother;
856 
857 					c = nbuf[noffset];
858 					if (c == '\0') {
859 						/*
860 						 * A '\0' at the
861 						 * beginning is
862 						 * obviously wrong.
863 						 * Any other '\0'
864 						 * means we're done.
865 						 */
866 						if (j == 0)
867 							goto tryanother;
868 						else
869 							break;
870 					} else {
871 						/*
872 						 * A nonprintable
873 						 * character is also
874 						 * wrong.
875 						 */
876 						if (!isprint(c) || isquote(c))
877 							goto tryanother;
878 					}
879 				}
880 				/*
881 				 * Well, that worked.
882 				 */
883 
884 				/*
885 				 * Try next offsets, in case this match is
886 				 * in the middle of a string.
887 				 */
888 				for (k = i + 1 ; k < NOFFSETS; k++) {
889 					size_t no;
890 					int adjust = 1;
891 					if (prpsoffsets(k) >= prpsoffsets(i))
892 						continue;
893 					for (no = doff + prpsoffsets(k);
894 					     no < doff + prpsoffsets(i); no++)
895 						adjust = adjust
896 						         && isprint(nbuf[no]);
897 					if (adjust)
898 						i = k;
899 				}
900 
901 				cname = CAST(unsigned char *,
902 				    &nbuf[doff + prpsoffsets(i)]);
903 				for (cp = cname; cp < nbuf + size && *cp
904 				    && isprint(*cp); cp++)
905 					continue;
906 				/*
907 				 * Linux apparently appends a space at the end
908 				 * of the command line: remove it.
909 				 */
910 				while (cp > cname && isspace(cp[-1]))
911 					cp--;
912 				if (file_printf(ms, ", from '%s'",
913 				    file_copystr(buf, sizeof(buf),
914 				    CAST(size_t, cp - cname),
915 				    CAST(const char *, cname))) == -1)
916 					return -1;
917 				*flags |= FLAGS_DID_CORE;
918 				return 1;
919 
920 			tryanother:
921 				;
922 			}
923 		}
924 		break;
925 	}
926 #endif
927 	return 0;
928 }
929 
930 private off_t
931 get_offset_from_virtaddr(struct magic_set *ms, int swap, int clazz, int fd,
932     off_t off, int num, off_t fsize, uint64_t virtaddr)
933 {
934 	Elf32_Phdr ph32;
935 	Elf64_Phdr ph64;
936 
937 	/*
938 	 * Loop through all the program headers and find the header with
939 	 * virtual address in which the "virtaddr" belongs to.
940 	 */
941 	for ( ; num; num--) {
942 		if (pread(fd, xph_addr, xph_sizeof, off) <
943 		    CAST(ssize_t, xph_sizeof)) {
944 			file_badread(ms);
945 			return -1;
946 		}
947 		off += xph_sizeof;
948 
949 		if (fsize != SIZE_UNKNOWN && xph_offset > fsize) {
950 			/* Perhaps warn here */
951 			continue;
952 		}
953 
954 		if (virtaddr >= xph_vaddr && virtaddr < xph_vaddr + xph_filesz)
955 			return xph_offset + (virtaddr - xph_vaddr);
956 	}
957 	return 0;
958 }
959 
960 private size_t
961 get_string_on_virtaddr(struct magic_set *ms,
962     int swap, int clazz, int fd, off_t ph_off, int ph_num,
963     off_t fsize, uint64_t virtaddr, char *buf, ssize_t buflen)
964 {
965 	char *bptr;
966 	off_t offset;
967 
968 	if (buflen == 0)
969 		return 0;
970 
971 	offset = get_offset_from_virtaddr(ms, swap, clazz, fd, ph_off, ph_num,
972 	    fsize, virtaddr);
973 	if (offset < 0 ||
974 	    (buflen = pread(fd, buf, CAST(size_t, buflen), offset)) <= 0) {
975 		file_badread(ms);
976 		return 0;
977 	}
978 
979 	buf[buflen - 1] = '\0';
980 
981 	/* We expect only printable characters, so return if buffer contains
982 	 * non-printable character before the '\0' or just '\0'. */
983 	for (bptr = buf; *bptr && isprint(CAST(unsigned char, *bptr)); bptr++)
984 		continue;
985 	if (*bptr != '\0')
986 		return 0;
987 
988 	return bptr - buf;
989 }
990 
991 
992 /*ARGSUSED*/
993 private int
994 do_auxv_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type,
995     int swap, uint32_t namesz __attribute__((__unused__)),
996     uint32_t descsz __attribute__((__unused__)),
997     size_t noff __attribute__((__unused__)), size_t doff,
998     int *flags, size_t size __attribute__((__unused__)), int clazz,
999     int fd, off_t ph_off, int ph_num, off_t fsize)
1000 {
1001 #ifdef ELFCORE
1002 	Aux32Info auxv32;
1003 	Aux64Info auxv64;
1004 	size_t elsize = xauxv_sizeof;
1005 	const char *tag;
1006 	int is_string;
1007 	size_t nval;
1008 
1009 	if ((*flags & (FLAGS_IS_CORE|FLAGS_DID_CORE_STYLE)) !=
1010 	    (FLAGS_IS_CORE|FLAGS_DID_CORE_STYLE))
1011 		return 0;
1012 
1013 	switch (*flags & FLAGS_CORE_STYLE) {
1014 	case OS_STYLE_SVR4:
1015 		if (type != NT_AUXV)
1016 			return 0;
1017 		break;
1018 #ifdef notyet
1019 	case OS_STYLE_NETBSD:
1020 		if (type != NT_NETBSD_CORE_AUXV)
1021 			return 0;
1022 		break;
1023 	case OS_STYLE_FREEBSD:
1024 		if (type != NT_FREEBSD_PROCSTAT_AUXV)
1025 			return 0;
1026 		break;
1027 #endif
1028 	default:
1029 		return 0;
1030 	}
1031 
1032 	*flags |= FLAGS_DID_AUXV;
1033 
1034 	nval = 0;
1035 	for (size_t off = 0; off + elsize <= descsz; off += elsize) {
1036 		memcpy(xauxv_addr, &nbuf[doff + off], xauxv_sizeof);
1037 		/* Limit processing to 50 vector entries to prevent DoS */
1038 		if (nval++ >= 50) {
1039 			file_error(ms, 0, "Too many ELF Auxv elements");
1040 			return 1;
1041 		}
1042 
1043 		switch(xauxv_type) {
1044 		case AT_LINUX_EXECFN:
1045 			is_string = 1;
1046 			tag = "execfn";
1047 			break;
1048 		case AT_LINUX_PLATFORM:
1049 			is_string = 1;
1050 			tag = "platform";
1051 			break;
1052 		case AT_LINUX_UID:
1053 			is_string = 0;
1054 			tag = "real uid";
1055 			break;
1056 		case AT_LINUX_GID:
1057 			is_string = 0;
1058 			tag = "real gid";
1059 			break;
1060 		case AT_LINUX_EUID:
1061 			is_string = 0;
1062 			tag = "effective uid";
1063 			break;
1064 		case AT_LINUX_EGID:
1065 			is_string = 0;
1066 			tag = "effective gid";
1067 			break;
1068 		default:
1069 			is_string = 0;
1070 			tag = NULL;
1071 			break;
1072 		}
1073 
1074 		if (tag == NULL)
1075 			continue;
1076 
1077 		if (is_string) {
1078 			char buf[256];
1079 			ssize_t buflen;
1080 			buflen = get_string_on_virtaddr(ms, swap, clazz, fd,
1081 			    ph_off, ph_num, fsize, xauxv_val, buf, sizeof(buf));
1082 
1083 			if (buflen == 0)
1084 				continue;
1085 
1086 			if (file_printf(ms, ", %s: '%s'", tag, buf) == -1)
1087 				return -1;
1088 		} else {
1089 			if (file_printf(ms, ", %s: %d", tag,
1090 			    CAST(int, xauxv_val)) == -1)
1091 				return -1;
1092 		}
1093 	}
1094 	return 1;
1095 #else
1096 	return 0;
1097 #endif
1098 }
1099 
1100 private size_t
1101 dodynamic(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
1102     int clazz, int swap)
1103 {
1104 	Elf32_Dyn dh32;
1105 	Elf64_Dyn dh64;
1106 	unsigned char *dbuf = CAST(unsigned char *, vbuf);
1107 
1108 	if (xdh_sizeof + offset > size) {
1109 		/*
1110 		 * We're out of note headers.
1111 		 */
1112 		return xdh_sizeof + offset;
1113 	}
1114 
1115 	memcpy(xdh_addr, &dbuf[offset], xdh_sizeof);
1116 	offset += xdh_sizeof;
1117 
1118 	switch (xdh_tag) {
1119 	case DT_FLAGS_1:
1120 		if (xdh_val & DF_1_PIE)
1121 			ms->mode |= 0111;
1122 		else
1123 			ms->mode &= ~0111;
1124 		break;
1125 	default:
1126 		break;
1127 	}
1128 	return offset;
1129 }
1130 
1131 
1132 private size_t
1133 donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
1134     int clazz, int swap, size_t align, int *flags, uint16_t *notecount,
1135     int fd, off_t ph_off, int ph_num, off_t fsize)
1136 {
1137 	Elf32_Nhdr nh32;
1138 	Elf64_Nhdr nh64;
1139 	size_t noff, doff;
1140 	uint32_t namesz, descsz;
1141 	char buf[256];
1142 	unsigned char *nbuf = CAST(unsigned char *, vbuf);
1143 
1144 	if (*notecount == 0)
1145 		return 0;
1146 	--*notecount;
1147 
1148 	if (xnh_sizeof + offset > size) {
1149 		/*
1150 		 * We're out of note headers.
1151 		 */
1152 		return xnh_sizeof + offset;
1153 	}
1154 	/*XXX: GCC */
1155 	memset(&nh32, 0, sizeof(nh32));
1156 	memset(&nh64, 0, sizeof(nh64));
1157 
1158 	memcpy(xnh_addr, &nbuf[offset], xnh_sizeof);
1159 	offset += xnh_sizeof;
1160 
1161 	namesz = xnh_namesz;
1162 	descsz = xnh_descsz;
1163 
1164 	if ((namesz == 0) && (descsz == 0)) {
1165 		/*
1166 		 * We're out of note headers.
1167 		 */
1168 		return (offset >= size) ? offset : size;
1169 	}
1170 
1171 	if (namesz & 0x80000000) {
1172 		if (file_printf(ms, ", bad note name size %#lx",
1173 		    CAST(unsigned long, namesz)) == -1)
1174 			return -1;
1175 	    return 0;
1176 	}
1177 
1178 	if (descsz & 0x80000000) {
1179 		if (file_printf(ms, ", bad note description size %#lx",
1180 		    CAST(unsigned long, descsz)) == -1)
1181 		    	return -1;
1182 	    return 0;
1183 	}
1184 
1185 	noff = offset;
1186 	doff = ELF_ALIGN(offset + namesz);
1187 
1188 	if (offset + namesz > size) {
1189 		/*
1190 		 * We're past the end of the buffer.
1191 		 */
1192 		return doff;
1193 	}
1194 
1195 	offset = ELF_ALIGN(doff + descsz);
1196 	if (doff + descsz > size) {
1197 		/*
1198 		 * We're past the end of the buffer.
1199 		 */
1200 		return (offset >= size) ? offset : size;
1201 	}
1202 
1203 
1204 	if ((*flags & FLAGS_DID_OS_NOTE) == 0) {
1205 		if (do_os_note(ms, nbuf, xnh_type, swap,
1206 		    namesz, descsz, noff, doff, flags))
1207 			return offset;
1208 	}
1209 
1210 	if ((*flags & FLAGS_DID_BUILD_ID) == 0) {
1211 		if (do_bid_note(ms, nbuf, xnh_type, swap,
1212 		    namesz, descsz, noff, doff, flags))
1213 			return offset;
1214 	}
1215 
1216 	if ((*flags & FLAGS_DID_NETBSD_PAX) == 0) {
1217 		if (do_pax_note(ms, nbuf, xnh_type, swap,
1218 		    namesz, descsz, noff, doff, flags))
1219 			return offset;
1220 	}
1221 
1222 	if ((*flags & FLAGS_DID_CORE) == 0) {
1223 		if (do_core_note(ms, nbuf, xnh_type, swap,
1224 		    namesz, descsz, noff, doff, flags, size, clazz))
1225 			return offset;
1226 	}
1227 
1228 	if ((*flags & FLAGS_DID_AUXV) == 0) {
1229 		if (do_auxv_note(ms, nbuf, xnh_type, swap,
1230 			namesz, descsz, noff, doff, flags, size, clazz,
1231 			fd, ph_off, ph_num, fsize))
1232 			return offset;
1233 	}
1234 
1235 	if (namesz == 7 && strcmp(RCAST(char *, &nbuf[noff]), "NetBSD") == 0) {
1236 		int descw, flag;
1237 		const char *str, *tag;
1238 		if (descsz > 100)
1239 			descsz = 100;
1240 		switch (xnh_type) {
1241 	    	case NT_NETBSD_VERSION:
1242 			return offset;
1243 		case NT_NETBSD_MARCH:
1244 			flag = FLAGS_DID_NETBSD_MARCH;
1245 			tag = "compiled for";
1246 			break;
1247 		case NT_NETBSD_CMODEL:
1248 			flag = FLAGS_DID_NETBSD_CMODEL;
1249 			tag = "compiler model";
1250 			break;
1251 		case NT_NETBSD_EMULATION:
1252 			flag = FLAGS_DID_NETBSD_EMULATION;
1253 			tag = "emulation:";
1254 			break;
1255 		default:
1256 			if (*flags & FLAGS_DID_NETBSD_UNKNOWN)
1257 				return offset;
1258 			*flags |= FLAGS_DID_NETBSD_UNKNOWN;
1259 			if (file_printf(ms, ", note=%u", xnh_type) == -1)
1260 				return offset;
1261 			return offset;
1262 		}
1263 
1264 		if (*flags & flag)
1265 			return offset;
1266 		str = RCAST(const char *, &nbuf[doff]);
1267 		descw = CAST(int, descsz);
1268 		*flags |= flag;
1269 		file_printf(ms, ", %s: %s", tag,
1270 		    file_copystr(buf, sizeof(buf), descw, str));
1271 		return offset;
1272 	}
1273 
1274 	return offset;
1275 }
1276 
1277 /* SunOS 5.x hardware capability descriptions */
1278 typedef struct cap_desc {
1279 	uint64_t cd_mask;
1280 	const char *cd_name;
1281 } cap_desc_t;
1282 
1283 static const cap_desc_t cap_desc_sparc[] = {
1284 	{ AV_SPARC_MUL32,		"MUL32" },
1285 	{ AV_SPARC_DIV32,		"DIV32" },
1286 	{ AV_SPARC_FSMULD,		"FSMULD" },
1287 	{ AV_SPARC_V8PLUS,		"V8PLUS" },
1288 	{ AV_SPARC_POPC,		"POPC" },
1289 	{ AV_SPARC_VIS,			"VIS" },
1290 	{ AV_SPARC_VIS2,		"VIS2" },
1291 	{ AV_SPARC_ASI_BLK_INIT,	"ASI_BLK_INIT" },
1292 	{ AV_SPARC_FMAF,		"FMAF" },
1293 	{ AV_SPARC_FJFMAU,		"FJFMAU" },
1294 	{ AV_SPARC_IMA,			"IMA" },
1295 	{ 0, NULL }
1296 };
1297 
1298 static const cap_desc_t cap_desc_386[] = {
1299 	{ AV_386_FPU,			"FPU" },
1300 	{ AV_386_TSC,			"TSC" },
1301 	{ AV_386_CX8,			"CX8" },
1302 	{ AV_386_SEP,			"SEP" },
1303 	{ AV_386_AMD_SYSC,		"AMD_SYSC" },
1304 	{ AV_386_CMOV,			"CMOV" },
1305 	{ AV_386_MMX,			"MMX" },
1306 	{ AV_386_AMD_MMX,		"AMD_MMX" },
1307 	{ AV_386_AMD_3DNow,		"AMD_3DNow" },
1308 	{ AV_386_AMD_3DNowx,		"AMD_3DNowx" },
1309 	{ AV_386_FXSR,			"FXSR" },
1310 	{ AV_386_SSE,			"SSE" },
1311 	{ AV_386_SSE2,			"SSE2" },
1312 	{ AV_386_PAUSE,			"PAUSE" },
1313 	{ AV_386_SSE3,			"SSE3" },
1314 	{ AV_386_MON,			"MON" },
1315 	{ AV_386_CX16,			"CX16" },
1316 	{ AV_386_AHF,			"AHF" },
1317 	{ AV_386_TSCP,			"TSCP" },
1318 	{ AV_386_AMD_SSE4A,		"AMD_SSE4A" },
1319 	{ AV_386_POPCNT,		"POPCNT" },
1320 	{ AV_386_AMD_LZCNT,		"AMD_LZCNT" },
1321 	{ AV_386_SSSE3,			"SSSE3" },
1322 	{ AV_386_SSE4_1,		"SSE4.1" },
1323 	{ AV_386_SSE4_2,		"SSE4.2" },
1324 	{ 0, NULL }
1325 };
1326 
1327 private int
1328 doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
1329     size_t size, off_t fsize, int mach, int strtab, int *flags,
1330     uint16_t *notecount)
1331 {
1332 	Elf32_Shdr sh32;
1333 	Elf64_Shdr sh64;
1334 	int stripped = 1, has_debug_info = 0;
1335 	size_t nbadcap = 0;
1336 	void *nbuf;
1337 	off_t noff, coff, name_off;
1338 	uint64_t cap_hw1 = 0;	/* SunOS 5.x hardware capabilities */
1339 	uint64_t cap_sf1 = 0;	/* SunOS 5.x software capabilities */
1340 	char name[50];
1341 	ssize_t namesize;
1342 
1343 	if (ms->flags & MAGIC_MIME)
1344 		return 0;
1345 
1346 	if (num == 0) {
1347 		if (file_printf(ms, ", no section header") == -1)
1348 			return -1;
1349 		return 0;
1350 	}
1351 	if (size != xsh_sizeof) {
1352 		if (file_printf(ms, ", corrupted section header size") == -1)
1353 			return -1;
1354 		return 0;
1355 	}
1356 
1357 	/* Read offset of name section to be able to read section names later */
1358 	if (pread(fd, xsh_addr, xsh_sizeof, CAST(off_t, (off + size * strtab)))
1359 	    < CAST(ssize_t, xsh_sizeof)) {
1360 		if (file_printf(ms, ", missing section headers") == -1)
1361 			return -1;
1362 		return 0;
1363 	}
1364 	name_off = xsh_offset;
1365 
1366 	if (fsize != SIZE_UNKNOWN && fsize < name_off) {
1367 		if (file_printf(ms, ", too large section header offset %jd",
1368 		    (intmax_t)name_off) == -1)
1369 			return -1;
1370 		return 0;
1371 	}
1372 
1373 	for ( ; num; num--) {
1374 		/* Read the name of this section. */
1375 		if ((namesize = pread(fd, name, sizeof(name) - 1,
1376 		    name_off + xsh_name)) == -1) {
1377 			file_badread(ms);
1378 			return -1;
1379 		}
1380 		name[namesize] = '\0';
1381 		if (strcmp(name, ".debug_info") == 0) {
1382 			has_debug_info = 1;
1383 			stripped = 0;
1384 		}
1385 
1386 		if (pread(fd, xsh_addr, xsh_sizeof, off) <
1387 		    CAST(ssize_t, xsh_sizeof)) {
1388 			file_badread(ms);
1389 			return -1;
1390 		}
1391 		off += size;
1392 
1393 		/* Things we can determine before we seek */
1394 		switch (xsh_type) {
1395 		case SHT_SYMTAB:
1396 #if 0
1397 		case SHT_DYNSYM:
1398 #endif
1399 			stripped = 0;
1400 			break;
1401 		default:
1402 			if (fsize != SIZE_UNKNOWN && xsh_offset > fsize) {
1403 				/* Perhaps warn here */
1404 				continue;
1405 			}
1406 			break;
1407 		}
1408 
1409 
1410 		/* Things we can determine when we seek */
1411 		switch (xsh_type) {
1412 		case SHT_NOTE:
1413 			if (CAST(uintmax_t, (xsh_size + xsh_offset)) >
1414 			    CAST(uintmax_t, fsize)) {
1415 				if (file_printf(ms,
1416 				    ", note offset/size %#" INTMAX_T_FORMAT
1417 				    "x+%#" INTMAX_T_FORMAT "x exceeds"
1418 				    " file size %#" INTMAX_T_FORMAT "x",
1419 				    CAST(uintmax_t, xsh_offset),
1420 				    CAST(uintmax_t, xsh_size),
1421 				    CAST(uintmax_t, fsize)) == -1)
1422 					return -1;
1423 				return 0;
1424 			}
1425 			if ((nbuf = malloc(xsh_size)) == NULL) {
1426 				file_error(ms, errno, "Cannot allocate memory"
1427 				    " for note");
1428 				return -1;
1429 			}
1430 			if (pread(fd, nbuf, xsh_size, xsh_offset) <
1431 			    CAST(ssize_t, xsh_size)) {
1432 				file_badread(ms);
1433 				free(nbuf);
1434 				return -1;
1435 			}
1436 
1437 			noff = 0;
1438 			for (;;) {
1439 				if (noff >= CAST(off_t, xsh_size))
1440 					break;
1441 				noff = donote(ms, nbuf, CAST(size_t, noff),
1442 				    xsh_size, clazz, swap, 4, flags, notecount,
1443 				    fd, 0, 0, 0);
1444 				if (noff == 0)
1445 					break;
1446 			}
1447 			free(nbuf);
1448 			break;
1449 		case SHT_SUNW_cap:
1450 			switch (mach) {
1451 			case EM_SPARC:
1452 			case EM_SPARCV9:
1453 			case EM_IA_64:
1454 			case EM_386:
1455 			case EM_AMD64:
1456 				break;
1457 			default:
1458 				goto skip;
1459 			}
1460 
1461 			if (nbadcap > 5)
1462 				break;
1463 			if (lseek(fd, xsh_offset, SEEK_SET)
1464 			    == CAST(off_t, -1)) {
1465 				file_badseek(ms);
1466 				return -1;
1467 			}
1468 			coff = 0;
1469 			for (;;) {
1470 				Elf32_Cap cap32;
1471 				Elf64_Cap cap64;
1472 				char cbuf[/*CONSTCOND*/
1473 				    MAX(sizeof(cap32), sizeof(cap64))];
1474 				if ((coff += xcap_sizeof) >
1475 				    CAST(off_t, xsh_size))
1476 					break;
1477 				if (read(fd, cbuf, CAST(size_t, xcap_sizeof)) !=
1478 				    CAST(ssize_t, xcap_sizeof)) {
1479 					file_badread(ms);
1480 					return -1;
1481 				}
1482 				if (cbuf[0] == 'A') {
1483 #ifdef notyet
1484 					char *p = cbuf + 1;
1485 					uint32_t len, tag;
1486 					memcpy(&len, p, sizeof(len));
1487 					p += 4;
1488 					len = getu32(swap, len);
1489 					if (memcmp("gnu", p, 3) != 0) {
1490 					    if (file_printf(ms,
1491 						", unknown capability %.3s", p)
1492 						== -1)
1493 						return -1;
1494 					    break;
1495 					}
1496 					p += strlen(p) + 1;
1497 					tag = *p++;
1498 					memcpy(&len, p, sizeof(len));
1499 					p += 4;
1500 					len = getu32(swap, len);
1501 					if (tag != 1) {
1502 					    if (file_printf(ms, ", unknown gnu"
1503 						" capability tag %d", tag)
1504 						== -1)
1505 						return -1;
1506 					    break;
1507 					}
1508 					// gnu attributes
1509 #endif
1510 					break;
1511 				}
1512 				memcpy(xcap_addr, cbuf, xcap_sizeof);
1513 				switch (xcap_tag) {
1514 				case CA_SUNW_NULL:
1515 					break;
1516 				case CA_SUNW_HW_1:
1517 					cap_hw1 |= xcap_val;
1518 					break;
1519 				case CA_SUNW_SF_1:
1520 					cap_sf1 |= xcap_val;
1521 					break;
1522 				default:
1523 					if (file_printf(ms,
1524 					    ", with unknown capability "
1525 					    "%#" INT64_T_FORMAT "x = %#"
1526 					    INT64_T_FORMAT "x",
1527 					    CAST(unsigned long long, xcap_tag),
1528 					    CAST(unsigned long long, xcap_val))
1529 					    == -1)
1530 						return -1;
1531 					if (nbadcap++ > 2)
1532 						coff = xsh_size;
1533 					break;
1534 				}
1535 			}
1536 			/*FALLTHROUGH*/
1537 		skip:
1538 		default:
1539 			break;
1540 		}
1541 	}
1542 
1543 	if (has_debug_info) {
1544 		if (file_printf(ms, ", with debug_info") == -1)
1545 			return -1;
1546 	}
1547 	if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1)
1548 		return -1;
1549 	if (cap_hw1) {
1550 		const cap_desc_t *cdp;
1551 		switch (mach) {
1552 		case EM_SPARC:
1553 		case EM_SPARC32PLUS:
1554 		case EM_SPARCV9:
1555 			cdp = cap_desc_sparc;
1556 			break;
1557 		case EM_386:
1558 		case EM_IA_64:
1559 		case EM_AMD64:
1560 			cdp = cap_desc_386;
1561 			break;
1562 		default:
1563 			cdp = NULL;
1564 			break;
1565 		}
1566 		if (file_printf(ms, ", uses") == -1)
1567 			return -1;
1568 		if (cdp) {
1569 			while (cdp->cd_name) {
1570 				if (cap_hw1 & cdp->cd_mask) {
1571 					if (file_printf(ms,
1572 					    " %s", cdp->cd_name) == -1)
1573 						return -1;
1574 					cap_hw1 &= ~cdp->cd_mask;
1575 				}
1576 				++cdp;
1577 			}
1578 			if (cap_hw1)
1579 				if (file_printf(ms,
1580 				    " unknown hardware capability %#"
1581 				    INT64_T_FORMAT "x",
1582 				    CAST(unsigned long long, cap_hw1)) == -1)
1583 					return -1;
1584 		} else {
1585 			if (file_printf(ms,
1586 			    " hardware capability %#" INT64_T_FORMAT "x",
1587 			    CAST(unsigned long long, cap_hw1)) == -1)
1588 				return -1;
1589 		}
1590 	}
1591 	if (cap_sf1) {
1592 		if (cap_sf1 & SF1_SUNW_FPUSED) {
1593 			if (file_printf(ms,
1594 			    (cap_sf1 & SF1_SUNW_FPKNWN)
1595 			    ? ", uses frame pointer"
1596 			    : ", not known to use frame pointer") == -1)
1597 				return -1;
1598 		}
1599 		cap_sf1 &= ~SF1_SUNW_MASK;
1600 		if (cap_sf1)
1601 			if (file_printf(ms,
1602 			    ", with unknown software capability %#"
1603 			    INT64_T_FORMAT "x",
1604 			    CAST(unsigned long long, cap_sf1)) == -1)
1605 				return -1;
1606 	}
1607 	return 0;
1608 }
1609 
1610 /*
1611  * Look through the program headers of an executable image, searching
1612  * for a PT_INTERP section; if one is found, it's dynamically linked,
1613  * otherwise it's statically linked.
1614  */
1615 private int
1616 dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
1617     int num, size_t size, off_t fsize, int sh_num, int *flags,
1618     uint16_t *notecount)
1619 {
1620 	Elf32_Phdr ph32;
1621 	Elf64_Phdr ph64;
1622 	const char *linking_style = "statically";
1623 	unsigned char nbuf[BUFSIZ];
1624 	char ibuf[BUFSIZ];
1625 	char interp[BUFSIZ];
1626 	ssize_t bufsize;
1627 	size_t offset, align, len;
1628 
1629 	if (num == 0) {
1630 		if (file_printf(ms, ", no program header") == -1)
1631 			return -1;
1632 		return 0;
1633 	}
1634 	if (size != xph_sizeof) {
1635 		if (file_printf(ms, ", corrupted program header size") == -1)
1636 			return -1;
1637 		return 0;
1638 	}
1639 
1640 	interp[0] = '\0';
1641   	for ( ; num; num--) {
1642 		int doread;
1643 		if (pread(fd, xph_addr, xph_sizeof, off) <
1644 		    CAST(ssize_t, xph_sizeof)) {
1645 			file_badread(ms);
1646 			return -1;
1647 		}
1648 
1649 		off += size;
1650 		bufsize = 0;
1651 		align = 4;
1652 
1653 		/* Things we can determine before we seek */
1654 		switch (xph_type) {
1655 		case PT_DYNAMIC:
1656 			doread = 1;
1657 			linking_style = "dynamically";
1658 			break;
1659 		case PT_NOTE:
1660 			if (sh_num)	/* Did this through section headers */
1661 				continue;
1662 			if (((align = xph_align) & 0x80000000UL) != 0 ||
1663 			    align < 4) {
1664 				if (file_printf(ms,
1665 				    ", invalid note alignment %#lx",
1666 				    CAST(unsigned long, align)) == -1)
1667 					return -1;
1668 				align = 4;
1669 			}
1670 			/*FALLTHROUGH*/
1671 		case PT_INTERP:
1672 			doread = 1;
1673 			break;
1674 		default:
1675 			doread = 0;
1676 			if (fsize != SIZE_UNKNOWN && xph_offset > fsize) {
1677 				/* Maybe warn here? */
1678 				continue;
1679 			}
1680 			break;
1681 		}
1682 
1683 		if (doread) {
1684 			len = xph_filesz < sizeof(nbuf) ? xph_filesz
1685 			    : sizeof(nbuf);
1686 			bufsize = pread(fd, nbuf, len, xph_offset);
1687 			if (bufsize == -1) {
1688 				file_badread(ms);
1689 				return -1;
1690 			}
1691 		} else
1692 			len = 0;
1693 
1694 		/* Things we can determine when we seek */
1695 		switch (xph_type) {
1696 		case PT_DYNAMIC:
1697 			offset = 0;
1698 			// Let DF_1 determine if we are PIE or not.
1699 			ms->mode &= ~0111;
1700 			for (;;) {
1701 				if (offset >= CAST(size_t, bufsize))
1702 					break;
1703 				offset = dodynamic(ms, nbuf, offset,
1704 				    CAST(size_t, bufsize), clazz, swap);
1705 				if (offset == 0)
1706 					break;
1707 			}
1708 			if (ms->flags & MAGIC_MIME)
1709 				continue;
1710 			break;
1711 
1712 		case PT_INTERP:
1713 			if (ms->flags & MAGIC_MIME)
1714 				continue;
1715 			if (bufsize && nbuf[0]) {
1716 				nbuf[bufsize - 1] = '\0';
1717 				memcpy(interp, nbuf, CAST(size_t, bufsize));
1718 			} else
1719 				strlcpy(interp, "*empty*", sizeof(interp));
1720 			break;
1721 		case PT_NOTE:
1722 			if (ms->flags & MAGIC_MIME)
1723 				return 0;
1724 			/*
1725 			 * This is a PT_NOTE section; loop through all the notes
1726 			 * in the section.
1727 			 */
1728 			offset = 0;
1729 			for (;;) {
1730 				if (offset >= CAST(size_t, bufsize))
1731 					break;
1732 				offset = donote(ms, nbuf, offset,
1733 				    CAST(size_t, bufsize), clazz, swap, align,
1734 				    flags, notecount, fd, 0, 0, 0);
1735 				if (offset == 0)
1736 					break;
1737 			}
1738 			break;
1739 		default:
1740 			if (ms->flags & MAGIC_MIME)
1741 				continue;
1742 			break;
1743 		}
1744 	}
1745 	if (ms->flags & MAGIC_MIME)
1746 		return 0;
1747 	if (file_printf(ms, ", %s linked", linking_style)
1748 	    == -1)
1749 		return -1;
1750 	if (interp[0])
1751 		if (file_printf(ms, ", interpreter %s",
1752 		    file_printable(ibuf, sizeof(ibuf), interp, sizeof(interp)))
1753 			== -1)
1754 			return -1;
1755 	return 0;
1756 }
1757 
1758 
1759 protected int
1760 file_tryelf(struct magic_set *ms, const struct buffer *b)
1761 {
1762 	int fd = b->fd;
1763 	const unsigned char *buf = CAST(const unsigned char *, b->fbuf);
1764 	size_t nbytes = b->flen;
1765 	union {
1766 		int32_t l;
1767 		char c[sizeof(int32_t)];
1768 	} u;
1769 	int clazz;
1770 	int swap;
1771 	struct stat st;
1772 	const struct stat *stp;
1773 	off_t fsize;
1774 	int flags = 0;
1775 	Elf32_Ehdr elf32hdr;
1776 	Elf64_Ehdr elf64hdr;
1777 	uint16_t type, phnum, shnum, notecount;
1778 
1779 	if (ms->flags & (MAGIC_APPLE|MAGIC_EXTENSION))
1780 		return 0;
1781 	/*
1782 	 * ELF executables have multiple section headers in arbitrary
1783 	 * file locations and thus file(1) cannot determine it from easily.
1784 	 * Instead we traverse thru all section headers until a symbol table
1785 	 * one is found or else the binary is stripped.
1786 	 * Return immediately if it's not ELF (so we avoid pipe2file unless
1787 	 * needed).
1788 	 */
1789 	if (buf[EI_MAG0] != ELFMAG0
1790 	    || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
1791 	    || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
1792 		return 0;
1793 
1794 	/*
1795 	 * If we cannot seek, it must be a pipe, socket or fifo.
1796 	 */
1797 	if((lseek(fd, CAST(off_t, 0), SEEK_SET) == CAST(off_t, -1))
1798 	    && (errno == ESPIPE))
1799 		fd = file_pipe2file(ms, fd, buf, nbytes);
1800 
1801 	if (fd == -1) {
1802 		file_badread(ms);
1803 		return -1;
1804 	}
1805 
1806 	stp = &b->st;
1807 	/*
1808 	 * b->st.st_size != 0 if previous fstat() succeeded,
1809 	 * which is likely, we can avoid extra stat() call.
1810 	 */
1811 	if (b->st.st_size == 0) {
1812 		stp = &st;
1813 		if (fstat(fd, &st) == -1) {
1814 			file_badread(ms);
1815 			return -1;
1816 		}
1817 	}
1818 	if (S_ISREG(stp->st_mode) || stp->st_size != 0)
1819 		fsize = stp->st_size;
1820 	else
1821 		fsize = SIZE_UNKNOWN;
1822 
1823 	clazz = buf[EI_CLASS];
1824 
1825 	switch (clazz) {
1826 	case ELFCLASS32:
1827 #undef elf_getu
1828 #define elf_getu(a, b)	elf_getu32(a, b)
1829 #undef elfhdr
1830 #define elfhdr elf32hdr
1831 #include "elfclass.h"
1832 	case ELFCLASS64:
1833 #undef elf_getu
1834 #define elf_getu(a, b)	elf_getu64(a, b)
1835 #undef elfhdr
1836 #define elfhdr elf64hdr
1837 #include "elfclass.h"
1838 	default:
1839 	    if (file_printf(ms, ", unknown class %d", clazz) == -1)
1840 		    return -1;
1841 	    break;
1842 	}
1843 	return 0;
1844 }
1845 #endif
1846