readelf.c revision 1.1.1.6 
1/*	$NetBSD: readelf.c,v 1.1.1.6 2013/12/01 19:28:17 christos Exp $	*/
2
3/*
4 * Copyright (c) Christos Zoulas 2003.
5 * All Rights Reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice immediately at the beginning of the file, without modification,
12 *    this list of conditions, and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29#include "file.h"
30
31#ifndef lint
32#if 0
33FILE_RCSID("@(#)$File: readelf.c,v 1.99 2013/11/05 15:44:01 christos Exp $")
34#else
35__RCSID("$NetBSD: readelf.c,v 1.1.1.6 2013/12/01 19:28:17 christos Exp $");
36#endif
37#endif
38
39#ifdef BUILTIN_ELF
40#include <string.h>
41#include <ctype.h>
42#include <stdlib.h>
43#ifdef HAVE_UNISTD_H
44#include <unistd.h>
45#endif
46
47#include "readelf.h"
48#include "magic.h"
49
50#ifdef	ELFCORE
51private int dophn_core(struct magic_set *, int, int, int, off_t, int, size_t,
52    off_t, int *);
53#endif
54private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t,
55    off_t, int *, int);
56private int doshn(struct magic_set *, int, int, int, off_t, int, size_t,
57    off_t, int *, int, int);
58private size_t donote(struct magic_set *, void *, size_t, size_t, int,
59    int, size_t, int *);
60
61#define	ELF_ALIGN(a)	((((a) + align - 1) / align) * align)
62
63#define isquote(c) (strchr("'\"`", (c)) != NULL)
64
65private uint16_t getu16(int, uint16_t);
66private uint32_t getu32(int, uint32_t);
67private uint64_t getu64(int, uint64_t);
68
69private uint16_t
70getu16(int swap, uint16_t value)
71{
72	union {
73		uint16_t ui;
74		char c[2];
75	} retval, tmpval;
76
77	if (swap) {
78		tmpval.ui = value;
79
80		retval.c[0] = tmpval.c[1];
81		retval.c[1] = tmpval.c[0];
82
83		return retval.ui;
84	} else
85		return value;
86}
87
88private uint32_t
89getu32(int swap, uint32_t value)
90{
91	union {
92		uint32_t ui;
93		char c[4];
94	} retval, tmpval;
95
96	if (swap) {
97		tmpval.ui = value;
98
99		retval.c[0] = tmpval.c[3];
100		retval.c[1] = tmpval.c[2];
101		retval.c[2] = tmpval.c[1];
102		retval.c[3] = tmpval.c[0];
103
104		return retval.ui;
105	} else
106		return value;
107}
108
109private uint64_t
110getu64(int swap, uint64_t value)
111{
112	union {
113		uint64_t ui;
114		char c[8];
115	} retval, tmpval;
116
117	if (swap) {
118		tmpval.ui = value;
119
120		retval.c[0] = tmpval.c[7];
121		retval.c[1] = tmpval.c[6];
122		retval.c[2] = tmpval.c[5];
123		retval.c[3] = tmpval.c[4];
124		retval.c[4] = tmpval.c[3];
125		retval.c[5] = tmpval.c[2];
126		retval.c[6] = tmpval.c[1];
127		retval.c[7] = tmpval.c[0];
128
129		return retval.ui;
130	} else
131		return value;
132}
133
134#define elf_getu16(swap, value) getu16(swap, value)
135#define elf_getu32(swap, value) getu32(swap, value)
136#define elf_getu64(swap, value) getu64(swap, value)
137
138#define xsh_addr	(clazz == ELFCLASS32			\
139			 ? (void *)&sh32			\
140			 : (void *)&sh64)
141#define xsh_sizeof	(clazz == ELFCLASS32			\
142			 ? sizeof(sh32)				\
143			 : sizeof(sh64))
144#define xsh_size	(size_t)(clazz == ELFCLASS32		\
145			 ? elf_getu32(swap, sh32.sh_size)	\
146			 : elf_getu64(swap, sh64.sh_size))
147#define xsh_offset	(off_t)(clazz == ELFCLASS32		\
148			 ? elf_getu32(swap, sh32.sh_offset)	\
149			 : elf_getu64(swap, sh64.sh_offset))
150#define xsh_type	(clazz == ELFCLASS32			\
151			 ? elf_getu32(swap, sh32.sh_type)	\
152			 : elf_getu32(swap, sh64.sh_type))
153#define xsh_name    	(clazz == ELFCLASS32			\
154			 ? elf_getu32(swap, sh32.sh_name)	\
155			 : elf_getu32(swap, sh64.sh_name))
156#define xph_addr	(clazz == ELFCLASS32			\
157			 ? (void *) &ph32			\
158			 : (void *) &ph64)
159#define xph_sizeof	(clazz == ELFCLASS32			\
160			 ? sizeof(ph32)				\
161			 : sizeof(ph64))
162#define xph_type	(clazz == ELFCLASS32			\
163			 ? elf_getu32(swap, ph32.p_type)	\
164			 : elf_getu32(swap, ph64.p_type))
165#define xph_offset	(off_t)(clazz == ELFCLASS32		\
166			 ? elf_getu32(swap, ph32.p_offset)	\
167			 : elf_getu64(swap, ph64.p_offset))
168#define xph_align	(size_t)((clazz == ELFCLASS32		\
169			 ? (off_t) (ph32.p_align ? 		\
170			    elf_getu32(swap, ph32.p_align) : 4) \
171			 : (off_t) (ph64.p_align ?		\
172			    elf_getu64(swap, ph64.p_align) : 4)))
173#define xph_filesz	(size_t)((clazz == ELFCLASS32		\
174			 ? elf_getu32(swap, ph32.p_filesz)	\
175			 : elf_getu64(swap, ph64.p_filesz)))
176#define xnh_addr	(clazz == ELFCLASS32			\
177			 ? (void *)&nh32			\
178			 : (void *)&nh64)
179#define xph_memsz	(size_t)((clazz == ELFCLASS32		\
180			 ? elf_getu32(swap, ph32.p_memsz)	\
181			 : elf_getu64(swap, ph64.p_memsz)))
182#define xnh_sizeof	(clazz == ELFCLASS32			\
183			 ? sizeof nh32				\
184			 : sizeof nh64)
185#define xnh_type	(clazz == ELFCLASS32			\
186			 ? elf_getu32(swap, nh32.n_type)	\
187			 : elf_getu32(swap, nh64.n_type))
188#define xnh_namesz	(clazz == ELFCLASS32			\
189			 ? elf_getu32(swap, nh32.n_namesz)	\
190			 : elf_getu32(swap, nh64.n_namesz))
191#define xnh_descsz	(clazz == ELFCLASS32			\
192			 ? elf_getu32(swap, nh32.n_descsz)	\
193			 : elf_getu32(swap, nh64.n_descsz))
194#define prpsoffsets(i)	(clazz == ELFCLASS32			\
195			 ? prpsoffsets32[i]			\
196			 : prpsoffsets64[i])
197#define xcap_addr	(clazz == ELFCLASS32			\
198			 ? (void *)&cap32			\
199			 : (void *)&cap64)
200#define xcap_sizeof	(clazz == ELFCLASS32			\
201			 ? sizeof cap32				\
202			 : sizeof cap64)
203#define xcap_tag	(clazz == ELFCLASS32			\
204			 ? elf_getu32(swap, cap32.c_tag)	\
205			 : elf_getu64(swap, cap64.c_tag))
206#define xcap_val	(clazz == ELFCLASS32			\
207			 ? elf_getu32(swap, cap32.c_un.c_val)	\
208			 : elf_getu64(swap, cap64.c_un.c_val))
209
210#ifdef ELFCORE
211/*
212 * Try larger offsets first to avoid false matches
213 * from earlier data that happen to look like strings.
214 */
215static const size_t	prpsoffsets32[] = {
216#ifdef USE_NT_PSINFO
217	104,		/* SunOS 5.x (command line) */
218	88,		/* SunOS 5.x (short name) */
219#endif /* USE_NT_PSINFO */
220
221	100,		/* SunOS 5.x (command line) */
222	84,		/* SunOS 5.x (short name) */
223
224	44,		/* Linux (command line) */
225	28,		/* Linux 2.0.36 (short name) */
226
227	8,		/* FreeBSD */
228};
229
230static const size_t	prpsoffsets64[] = {
231#ifdef USE_NT_PSINFO
232	152,		/* SunOS 5.x (command line) */
233	136,		/* SunOS 5.x (short name) */
234#endif /* USE_NT_PSINFO */
235
236	136,		/* SunOS 5.x, 64-bit (command line) */
237	120,		/* SunOS 5.x, 64-bit (short name) */
238
239	56,		/* Linux (command line) */
240	40,             /* Linux (tested on core from 2.4.x, short name) */
241
242	16,		/* FreeBSD, 64-bit */
243};
244
245#define	NOFFSETS32	(sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
246#define NOFFSETS64	(sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
247
248#define NOFFSETS	(clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
249
250/*
251 * Look through the program headers of an executable image, searching
252 * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
253 * "FreeBSD"; if one is found, try looking in various places in its
254 * contents for a 16-character string containing only printable
255 * characters - if found, that string should be the name of the program
256 * that dropped core.  Note: right after that 16-character string is,
257 * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
258 * Linux, a longer string (80 characters, in 5.x, probably other
259 * SVR4-flavored systems, and Linux) containing the start of the
260 * command line for that program.
261 *
262 * SunOS 5.x core files contain two PT_NOTE sections, with the types
263 * NT_PRPSINFO (old) and NT_PSINFO (new).  These structs contain the
264 * same info about the command name and command line, so it probably
265 * isn't worthwhile to look for NT_PSINFO, but the offsets are provided
266 * above (see USE_NT_PSINFO), in case we ever decide to do so.  The
267 * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent;
268 * the SunOS 5.x file command relies on this (and prefers the latter).
269 *
270 * The signal number probably appears in a section of type NT_PRSTATUS,
271 * but that's also rather OS-dependent, in ways that are harder to
272 * dissect with heuristics, so I'm not bothering with the signal number.
273 * (I suppose the signal number could be of interest in situations where
274 * you don't have the binary of the program that dropped core; if you
275 * *do* have that binary, the debugger will probably tell you what
276 * signal it was.)
277 */
278
279#define	OS_STYLE_SVR4		0
280#define	OS_STYLE_FREEBSD	1
281#define	OS_STYLE_NETBSD		2
282
283private const char os_style_names[][8] = {
284	"SVR4",
285	"FreeBSD",
286	"NetBSD",
287};
288
289#define FLAGS_DID_CORE		0x01
290#define FLAGS_DID_NOTE		0x02
291#define FLAGS_DID_BUILD_ID	0x04
292#define FLAGS_DID_CORE_STYLE	0x08
293#define FLAGS_IS_CORE		0x10
294
295private int
296dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
297    int num, size_t size, off_t fsize, int *flags)
298{
299	Elf32_Phdr ph32;
300	Elf64_Phdr ph64;
301	size_t offset, len;
302	unsigned char nbuf[BUFSIZ];
303	ssize_t bufsize;
304
305	if (size != xph_sizeof) {
306		if (file_printf(ms, ", corrupted program header size") == -1)
307			return -1;
308		return 0;
309	}
310
311	/*
312	 * Loop through all the program headers.
313	 */
314	for ( ; num; num--) {
315		if (pread(fd, xph_addr, xph_sizeof, off) == -1) {
316			file_badread(ms);
317			return -1;
318		}
319		off += size;
320
321		if (xph_offset > fsize) {
322			/* Perhaps warn here */
323			continue;
324		}
325
326		if (xph_type != PT_NOTE)
327			continue;
328
329		/*
330		 * This is a PT_NOTE section; loop through all the notes
331		 * in the section.
332		 */
333		len = xph_filesz < sizeof(nbuf) ? xph_filesz : sizeof(nbuf);
334		if ((bufsize = pread(fd, nbuf, len, xph_offset)) == -1) {
335			file_badread(ms);
336			return -1;
337		}
338		offset = 0;
339		for (;;) {
340			if (offset >= (size_t)bufsize)
341				break;
342			offset = donote(ms, nbuf, offset, (size_t)bufsize,
343			    clazz, swap, 4, flags);
344			if (offset == 0)
345				break;
346
347		}
348	}
349	return 0;
350}
351#endif
352
353static void
354do_note_netbsd_version(struct magic_set *ms, int swap, void *v)
355{
356	uint32_t desc;
357	(void)memcpy(&desc, v, sizeof(desc));
358	desc = elf_getu32(swap, desc);
359
360	if (file_printf(ms, ", for NetBSD") == -1)
361		return;
362	/*
363	 * The version number used to be stuck as 199905, and was thus
364	 * basically content-free.  Newer versions of NetBSD have fixed
365	 * this and now use the encoding of __NetBSD_Version__:
366	 *
367	 *	MMmmrrpp00
368	 *
369	 * M = major version
370	 * m = minor version
371	 * r = release ["",A-Z,Z[A-Z] but numeric]
372	 * p = patchlevel
373	 */
374	if (desc > 100000000U) {
375		uint32_t ver_patch = (desc / 100) % 100;
376		uint32_t ver_rel = (desc / 10000) % 100;
377		uint32_t ver_min = (desc / 1000000) % 100;
378		uint32_t ver_maj = desc / 100000000;
379
380		if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1)
381			return;
382		if (ver_rel == 0 && ver_patch != 0) {
383			if (file_printf(ms, ".%u", ver_patch) == -1)
384				return;
385		} else if (ver_rel != 0) {
386			while (ver_rel > 26) {
387				if (file_printf(ms, "Z") == -1)
388					return;
389				ver_rel -= 26;
390			}
391			if (file_printf(ms, "%c", 'A' + ver_rel - 1)
392			    == -1)
393				return;
394		}
395	}
396}
397
398static void
399do_note_freebsd_version(struct magic_set *ms, int swap, void *v)
400{
401	uint32_t desc;
402
403	(void)memcpy(&desc, v, sizeof(desc));
404	desc = elf_getu32(swap, desc);
405	if (file_printf(ms, ", for FreeBSD") == -1)
406		return;
407
408	/*
409	 * Contents is __FreeBSD_version, whose relation to OS
410	 * versions is defined by a huge table in the Porter's
411	 * Handbook.  This is the general scheme:
412	 *
413	 * Releases:
414	 * 	Mmp000 (before 4.10)
415	 * 	Mmi0p0 (before 5.0)
416	 * 	Mmm0p0
417	 *
418	 * Development branches:
419	 * 	Mmpxxx (before 4.6)
420	 * 	Mmp1xx (before 4.10)
421	 * 	Mmi1xx (before 5.0)
422	 * 	M000xx (pre-M.0)
423	 * 	Mmm1xx
424	 *
425	 * M = major version
426	 * m = minor version
427	 * i = minor version increment (491000 -> 4.10)
428	 * p = patchlevel
429	 * x = revision
430	 *
431	 * The first release of FreeBSD to use ELF by default
432	 * was version 3.0.
433	 */
434	if (desc == 460002) {
435		if (file_printf(ms, " 4.6.2") == -1)
436			return;
437	} else if (desc < 460100) {
438		if (file_printf(ms, " %d.%d", desc / 100000,
439		    desc / 10000 % 10) == -1)
440			return;
441		if (desc / 1000 % 10 > 0)
442			if (file_printf(ms, ".%d", desc / 1000 % 10) == -1)
443				return;
444		if ((desc % 1000 > 0) || (desc % 100000 == 0))
445			if (file_printf(ms, " (%d)", desc) == -1)
446				return;
447	} else if (desc < 500000) {
448		if (file_printf(ms, " %d.%d", desc / 100000,
449		    desc / 10000 % 10 + desc / 1000 % 10) == -1)
450			return;
451		if (desc / 100 % 10 > 0) {
452			if (file_printf(ms, " (%d)", desc) == -1)
453				return;
454		} else if (desc / 10 % 10 > 0) {
455			if (file_printf(ms, ".%d", desc / 10 % 10) == -1)
456				return;
457		}
458	} else {
459		if (file_printf(ms, " %d.%d", desc / 100000,
460		    desc / 1000 % 100) == -1)
461			return;
462		if ((desc / 100 % 10 > 0) ||
463		    (desc % 100000 / 100 == 0)) {
464			if (file_printf(ms, " (%d)", desc) == -1)
465				return;
466		} else if (desc / 10 % 10 > 0) {
467			if (file_printf(ms, ".%d", desc / 10 % 10) == -1)
468				return;
469		}
470	}
471}
472
473private size_t
474donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
475    int clazz, int swap, size_t align, int *flags)
476{
477	Elf32_Nhdr nh32;
478	Elf64_Nhdr nh64;
479	size_t noff, doff;
480#ifdef ELFCORE
481	int os_style = -1;
482#endif
483	uint32_t namesz, descsz;
484	unsigned char *nbuf = CAST(unsigned char *, vbuf);
485
486	(void)memcpy(xnh_addr, &nbuf[offset], xnh_sizeof);
487	offset += xnh_sizeof;
488
489	namesz = xnh_namesz;
490	descsz = xnh_descsz;
491	if ((namesz == 0) && (descsz == 0)) {
492		/*
493		 * We're out of note headers.
494		 */
495		return (offset >= size) ? offset : size;
496	}
497
498	if (namesz & 0x80000000) {
499	    (void)file_printf(ms, ", bad note name size 0x%lx",
500		(unsigned long)namesz);
501	    return offset;
502	}
503
504	if (descsz & 0x80000000) {
505	    (void)file_printf(ms, ", bad note description size 0x%lx",
506		(unsigned long)descsz);
507	    return offset;
508	}
509
510
511	noff = offset;
512	doff = ELF_ALIGN(offset + namesz);
513
514	if (offset + namesz > size) {
515		/*
516		 * We're past the end of the buffer.
517		 */
518		return doff;
519	}
520
521	offset = ELF_ALIGN(doff + descsz);
522	if (doff + descsz > size) {
523		/*
524		 * We're past the end of the buffer.
525		 */
526		return (offset >= size) ? offset : size;
527	}
528
529	if ((*flags & (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID)) ==
530	    (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID))
531		goto core;
532
533	if (namesz == 5 && strcmp((char *)&nbuf[noff], "SuSE") == 0 &&
534	    xnh_type == NT_GNU_VERSION && descsz == 2) {
535	    file_printf(ms, ", for SuSE %d.%d", nbuf[doff], nbuf[doff + 1]);
536	}
537	if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
538	    xnh_type == NT_GNU_VERSION && descsz == 16) {
539		uint32_t desc[4];
540		(void)memcpy(desc, &nbuf[doff], sizeof(desc));
541
542		if (file_printf(ms, ", for GNU/") == -1)
543			return size;
544		switch (elf_getu32(swap, desc[0])) {
545		case GNU_OS_LINUX:
546			if (file_printf(ms, "Linux") == -1)
547				return size;
548			break;
549		case GNU_OS_HURD:
550			if (file_printf(ms, "Hurd") == -1)
551				return size;
552			break;
553		case GNU_OS_SOLARIS:
554			if (file_printf(ms, "Solaris") == -1)
555				return size;
556			break;
557		case GNU_OS_KFREEBSD:
558			if (file_printf(ms, "kFreeBSD") == -1)
559				return size;
560			break;
561		case GNU_OS_KNETBSD:
562			if (file_printf(ms, "kNetBSD") == -1)
563				return size;
564			break;
565		default:
566			if (file_printf(ms, "<unknown>") == -1)
567				return size;
568		}
569		if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]),
570		    elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1)
571			return size;
572		*flags |= FLAGS_DID_NOTE;
573		return size;
574	}
575
576	if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
577	    xnh_type == NT_GNU_BUILD_ID && (descsz == 16 || descsz == 20)) {
578	    uint8_t desc[20];
579	    uint32_t i;
580	    if (file_printf(ms, ", BuildID[%s]=", descsz == 16 ? "md5/uuid" :
581		"sha1") == -1)
582		    return size;
583	    (void)memcpy(desc, &nbuf[doff], descsz);
584	    for (i = 0; i < descsz; i++)
585		if (file_printf(ms, "%02x", desc[i]) == -1)
586		    return size;
587	    *flags |= FLAGS_DID_BUILD_ID;
588	}
589
590	if (namesz == 4 && strcmp((char *)&nbuf[noff], "PaX") == 0 &&
591	    xnh_type == NT_NETBSD_PAX && descsz == 4) {
592		static const char *pax[] = {
593		    "+mprotect",
594		    "-mprotect",
595		    "+segvguard",
596		    "-segvguard",
597		    "+ASLR",
598		    "-ASLR",
599		};
600		uint32_t desc;
601		size_t i;
602		int did = 0;
603
604		(void)memcpy(&desc, &nbuf[doff], sizeof(desc));
605		desc = elf_getu32(swap, desc);
606
607		if (desc && file_printf(ms, ", PaX: ") == -1)
608			return size;
609
610		for (i = 0; i < __arraycount(pax); i++) {
611			if (((1 << i) & desc) == 0)
612				continue;
613			if (file_printf(ms, "%s%s", did++ ? "," : "",
614			    pax[i]) == -1)
615				return size;
616		}
617	}
618
619	if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0) {
620		switch (xnh_type) {
621		case NT_NETBSD_VERSION:
622			if (descsz == 4) {
623				do_note_netbsd_version(ms, swap, &nbuf[doff]);
624				*flags |= FLAGS_DID_NOTE;
625				return size;
626			}
627			break;
628		case NT_NETBSD_MARCH:
629			if (file_printf(ms, ", compiled for: %.*s", (int)descsz,
630			    (const char *)&nbuf[doff]) == -1)
631				return size;
632			break;
633		case NT_NETBSD_CMODEL:
634			if (file_printf(ms, ", compiler model: %.*s",
635			    (int)descsz, (const char *)&nbuf[doff]) == -1)
636				return size;
637			break;
638		default:
639			if (file_printf(ms, ", note=%u", xnh_type) == -1)
640				return size;
641			break;
642		}
643		return size;
644	}
645
646	if (namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0) {
647	    	if (xnh_type == NT_FREEBSD_VERSION && descsz == 4) {
648			do_note_freebsd_version(ms, swap, &nbuf[doff]);
649			*flags |= FLAGS_DID_NOTE;
650			return size;
651		}
652	}
653
654	if (namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 &&
655	    xnh_type == NT_OPENBSD_VERSION && descsz == 4) {
656		if (file_printf(ms, ", for OpenBSD") == -1)
657			return size;
658		/* Content of note is always 0 */
659		*flags |= FLAGS_DID_NOTE;
660		return size;
661	}
662
663	if (namesz == 10 && strcmp((char *)&nbuf[noff], "DragonFly") == 0 &&
664	    xnh_type == NT_DRAGONFLY_VERSION && descsz == 4) {
665		uint32_t desc;
666		if (file_printf(ms, ", for DragonFly") == -1)
667			return size;
668		(void)memcpy(&desc, &nbuf[doff], sizeof(desc));
669		desc = elf_getu32(swap, desc);
670		if (file_printf(ms, " %d.%d.%d", desc / 100000,
671		    desc / 10000 % 10, desc % 10000) == -1)
672			return size;
673		*flags |= FLAGS_DID_NOTE;
674		return size;
675	}
676
677core:
678	/*
679	 * Sigh.  The 2.0.36 kernel in Debian 2.1, at
680	 * least, doesn't correctly implement name
681	 * sections, in core dumps, as specified by
682	 * the "Program Linking" section of "UNIX(R) System
683	 * V Release 4 Programmer's Guide: ANSI C and
684	 * Programming Support Tools", because my copy
685	 * clearly says "The first 'namesz' bytes in 'name'
686	 * contain a *null-terminated* [emphasis mine]
687	 * character representation of the entry's owner
688	 * or originator", but the 2.0.36 kernel code
689	 * doesn't include the terminating null in the
690	 * name....
691	 */
692	if ((namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) ||
693	    (namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) {
694		os_style = OS_STYLE_SVR4;
695	}
696
697	if ((namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) {
698		os_style = OS_STYLE_FREEBSD;
699	}
700
701	if ((namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11)
702	    == 0)) {
703		os_style = OS_STYLE_NETBSD;
704	}
705
706#ifdef ELFCORE
707	if ((*flags & FLAGS_DID_CORE) != 0)
708		return size;
709
710	if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) {
711		if (file_printf(ms, ", %s-style", os_style_names[os_style])
712		    == -1)
713			return size;
714		*flags |= FLAGS_DID_CORE_STYLE;
715	}
716
717	switch (os_style) {
718	case OS_STYLE_NETBSD:
719		if (xnh_type == NT_NETBSD_CORE_PROCINFO) {
720			uint32_t signo;
721			/*
722			 * Extract the program name.  It is at
723			 * offset 0x7c, and is up to 32-bytes,
724			 * including the terminating NUL.
725			 */
726			if (file_printf(ms, ", from '%.31s'",
727			    &nbuf[doff + 0x7c]) == -1)
728				return size;
729
730			/*
731			 * Extract the signal number.  It is at
732			 * offset 0x08.
733			 */
734			(void)memcpy(&signo, &nbuf[doff + 0x08],
735			    sizeof(signo));
736			if (file_printf(ms, " (signal %u)",
737			    elf_getu32(swap, signo)) == -1)
738				return size;
739			*flags |= FLAGS_DID_CORE;
740			return size;
741		}
742		break;
743
744	default:
745		if (xnh_type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) {
746/*###709 [cc] warning: declaration of 'i' shadows previous non-variable%%%*/
747			size_t i, j;
748			unsigned char c;
749			/*
750			 * Extract the program name.  We assume
751			 * it to be 16 characters (that's what it
752			 * is in SunOS 5.x and Linux).
753			 *
754			 * Unfortunately, it's at a different offset
755			 * in various OSes, so try multiple offsets.
756			 * If the characters aren't all printable,
757			 * reject it.
758			 */
759			for (i = 0; i < NOFFSETS; i++) {
760				unsigned char *cname, *cp;
761				size_t reloffset = prpsoffsets(i);
762				size_t noffset = doff + reloffset;
763				size_t k;
764				for (j = 0; j < 16; j++, noffset++,
765				    reloffset++) {
766					/*
767					 * Make sure we're not past
768					 * the end of the buffer; if
769					 * we are, just give up.
770					 */
771					if (noffset >= size)
772						goto tryanother;
773
774					/*
775					 * Make sure we're not past
776					 * the end of the contents;
777					 * if we are, this obviously
778					 * isn't the right offset.
779					 */
780					if (reloffset >= descsz)
781						goto tryanother;
782
783					c = nbuf[noffset];
784					if (c == '\0') {
785						/*
786						 * A '\0' at the
787						 * beginning is
788						 * obviously wrong.
789						 * Any other '\0'
790						 * means we're done.
791						 */
792						if (j == 0)
793							goto tryanother;
794						else
795							break;
796					} else {
797						/*
798						 * A nonprintable
799						 * character is also
800						 * wrong.
801						 */
802						if (!isprint(c) || isquote(c))
803							goto tryanother;
804					}
805				}
806				/*
807				 * Well, that worked.
808				 */
809
810				/*
811				 * Try next offsets, in case this match is
812				 * in the middle of a string.
813				 */
814				for (k = i + 1 ; k < NOFFSETS ; k++) {
815					size_t no;
816					int adjust = 1;
817					if (prpsoffsets(k) >= prpsoffsets(i))
818						continue;
819					for (no = doff + prpsoffsets(k);
820					     no < doff + prpsoffsets(i); no++)
821						adjust = adjust
822						         && isprint(nbuf[no]);
823					if (adjust)
824						i = k;
825				}
826
827				cname = (unsigned char *)
828				    &nbuf[doff + prpsoffsets(i)];
829				for (cp = cname; *cp && isprint(*cp); cp++)
830					continue;
831				/*
832				 * Linux apparently appends a space at the end
833				 * of the command line: remove it.
834				 */
835				while (cp > cname && isspace(cp[-1]))
836					cp--;
837				if (file_printf(ms, ", from '%.*s'",
838				    (int)(cp - cname), cname) == -1)
839					return size;
840				*flags |= FLAGS_DID_CORE;
841				return size;
842
843			tryanother:
844				;
845			}
846		}
847		break;
848	}
849#endif
850	return offset;
851}
852
853/* SunOS 5.x hardware capability descriptions */
854typedef struct cap_desc {
855	uint64_t cd_mask;
856	const char *cd_name;
857} cap_desc_t;
858
859static const cap_desc_t cap_desc_sparc[] = {
860	{ AV_SPARC_MUL32,		"MUL32" },
861	{ AV_SPARC_DIV32,		"DIV32" },
862	{ AV_SPARC_FSMULD,		"FSMULD" },
863	{ AV_SPARC_V8PLUS,		"V8PLUS" },
864	{ AV_SPARC_POPC,		"POPC" },
865	{ AV_SPARC_VIS,			"VIS" },
866	{ AV_SPARC_VIS2,		"VIS2" },
867	{ AV_SPARC_ASI_BLK_INIT,	"ASI_BLK_INIT" },
868	{ AV_SPARC_FMAF,		"FMAF" },
869	{ AV_SPARC_FJFMAU,		"FJFMAU" },
870	{ AV_SPARC_IMA,			"IMA" },
871	{ 0, NULL }
872};
873
874static const cap_desc_t cap_desc_386[] = {
875	{ AV_386_FPU,			"FPU" },
876	{ AV_386_TSC,			"TSC" },
877	{ AV_386_CX8,			"CX8" },
878	{ AV_386_SEP,			"SEP" },
879	{ AV_386_AMD_SYSC,		"AMD_SYSC" },
880	{ AV_386_CMOV,			"CMOV" },
881	{ AV_386_MMX,			"MMX" },
882	{ AV_386_AMD_MMX,		"AMD_MMX" },
883	{ AV_386_AMD_3DNow,		"AMD_3DNow" },
884	{ AV_386_AMD_3DNowx,		"AMD_3DNowx" },
885	{ AV_386_FXSR,			"FXSR" },
886	{ AV_386_SSE,			"SSE" },
887	{ AV_386_SSE2,			"SSE2" },
888	{ AV_386_PAUSE,			"PAUSE" },
889	{ AV_386_SSE3,			"SSE3" },
890	{ AV_386_MON,			"MON" },
891	{ AV_386_CX16,			"CX16" },
892	{ AV_386_AHF,			"AHF" },
893	{ AV_386_TSCP,			"TSCP" },
894	{ AV_386_AMD_SSE4A,		"AMD_SSE4A" },
895	{ AV_386_POPCNT,		"POPCNT" },
896	{ AV_386_AMD_LZCNT,		"AMD_LZCNT" },
897	{ AV_386_SSSE3,			"SSSE3" },
898	{ AV_386_SSE4_1,		"SSE4.1" },
899	{ AV_386_SSE4_2,		"SSE4.2" },
900	{ 0, NULL }
901};
902
903private int
904doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
905    size_t size, off_t fsize, int *flags, int mach, int strtab)
906{
907	Elf32_Shdr sh32;
908	Elf64_Shdr sh64;
909	int stripped = 1;
910	void *nbuf;
911	off_t noff, coff, name_off;
912	uint64_t cap_hw1 = 0;	/* SunOS 5.x hardware capabilites */
913	uint64_t cap_sf1 = 0;	/* SunOS 5.x software capabilites */
914	char name[50];
915
916	if (size != xsh_sizeof) {
917		if (file_printf(ms, ", corrupted section header size") == -1)
918			return -1;
919		return 0;
920	}
921
922	/* Read offset of name section to be able to read section names later */
923	if (pread(fd, xsh_addr, xsh_sizeof, off + size * strtab) == -1) {
924		file_badread(ms);
925		return -1;
926	}
927	name_off = xsh_offset;
928
929	for ( ; num; num--) {
930		/* Read the name of this section. */
931		if (pread(fd, name, sizeof(name), name_off + xsh_name) == -1) {
932			file_badread(ms);
933			return -1;
934		}
935		name[sizeof(name) - 1] = '\0';
936		if (strcmp(name, ".debug_info") == 0)
937			stripped = 0;
938
939		if (pread(fd, xsh_addr, xsh_sizeof, off) == -1) {
940			file_badread(ms);
941			return -1;
942		}
943		off += size;
944
945		/* Things we can determine before we seek */
946		switch (xsh_type) {
947		case SHT_SYMTAB:
948#if 0
949		case SHT_DYNSYM:
950#endif
951			stripped = 0;
952			break;
953		default:
954			if (xsh_offset > fsize) {
955				/* Perhaps warn here */
956				continue;
957			}
958			break;
959		}
960
961		/* Things we can determine when we seek */
962		switch (xsh_type) {
963		case SHT_NOTE:
964			if ((nbuf = malloc(xsh_size)) == NULL) {
965				file_error(ms, errno, "Cannot allocate memory"
966				    " for note");
967				return -1;
968			}
969			if (pread(fd, nbuf, xsh_size, xsh_offset) == -1) {
970				file_badread(ms);
971				free(nbuf);
972				return -1;
973			}
974
975			noff = 0;
976			for (;;) {
977				if (noff >= (off_t)xsh_size)
978					break;
979				noff = donote(ms, nbuf, (size_t)noff,
980				    xsh_size, clazz, swap, 4, flags);
981				if (noff == 0)
982					break;
983			}
984			free(nbuf);
985			break;
986		case SHT_SUNW_cap:
987			switch (mach) {
988			case EM_SPARC:
989			case EM_SPARCV9:
990			case EM_IA_64:
991			case EM_386:
992			case EM_AMD64:
993				break;
994			default:
995				goto skip;
996			}
997
998			if (lseek(fd, xsh_offset, SEEK_SET) == (off_t)-1) {
999				file_badseek(ms);
1000				return -1;
1001			}
1002			coff = 0;
1003			for (;;) {
1004				Elf32_Cap cap32;
1005				Elf64_Cap cap64;
1006				char cbuf[/*CONSTCOND*/
1007				    MAX(sizeof cap32, sizeof cap64)];
1008				if ((coff += xcap_sizeof) > (off_t)xsh_size)
1009					break;
1010				if (read(fd, cbuf, (size_t)xcap_sizeof) !=
1011				    (ssize_t)xcap_sizeof) {
1012					file_badread(ms);
1013					return -1;
1014				}
1015				(void)memcpy(xcap_addr, cbuf, xcap_sizeof);
1016				switch (xcap_tag) {
1017				case CA_SUNW_NULL:
1018					break;
1019				case CA_SUNW_HW_1:
1020					cap_hw1 |= xcap_val;
1021					break;
1022				case CA_SUNW_SF_1:
1023					cap_sf1 |= xcap_val;
1024					break;
1025				default:
1026					if (file_printf(ms,
1027					    ", with unknown capability "
1028					    "0x%" INT64_T_FORMAT "x = 0x%"
1029					    INT64_T_FORMAT "x",
1030					    (unsigned long long)xcap_tag,
1031					    (unsigned long long)xcap_val) == -1)
1032						return -1;
1033					break;
1034				}
1035			}
1036			/*FALLTHROUGH*/
1037		skip:
1038		default:
1039			break;
1040		}
1041	}
1042
1043	if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1)
1044		return -1;
1045	if (cap_hw1) {
1046		const cap_desc_t *cdp;
1047		switch (mach) {
1048		case EM_SPARC:
1049		case EM_SPARC32PLUS:
1050		case EM_SPARCV9:
1051			cdp = cap_desc_sparc;
1052			break;
1053		case EM_386:
1054		case EM_IA_64:
1055		case EM_AMD64:
1056			cdp = cap_desc_386;
1057			break;
1058		default:
1059			cdp = NULL;
1060			break;
1061		}
1062		if (file_printf(ms, ", uses") == -1)
1063			return -1;
1064		if (cdp) {
1065			while (cdp->cd_name) {
1066				if (cap_hw1 & cdp->cd_mask) {
1067					if (file_printf(ms,
1068					    " %s", cdp->cd_name) == -1)
1069						return -1;
1070					cap_hw1 &= ~cdp->cd_mask;
1071				}
1072				++cdp;
1073			}
1074			if (cap_hw1)
1075				if (file_printf(ms,
1076				    " unknown hardware capability 0x%"
1077				    INT64_T_FORMAT "x",
1078				    (unsigned long long)cap_hw1) == -1)
1079					return -1;
1080		} else {
1081			if (file_printf(ms,
1082			    " hardware capability 0x%" INT64_T_FORMAT "x",
1083			    (unsigned long long)cap_hw1) == -1)
1084				return -1;
1085		}
1086	}
1087	if (cap_sf1) {
1088		if (cap_sf1 & SF1_SUNW_FPUSED) {
1089			if (file_printf(ms,
1090			    (cap_sf1 & SF1_SUNW_FPKNWN)
1091			    ? ", uses frame pointer"
1092			    : ", not known to use frame pointer") == -1)
1093				return -1;
1094		}
1095		cap_sf1 &= ~SF1_SUNW_MASK;
1096		if (cap_sf1)
1097			if (file_printf(ms,
1098			    ", with unknown software capability 0x%"
1099			    INT64_T_FORMAT "x",
1100			    (unsigned long long)cap_sf1) == -1)
1101				return -1;
1102	}
1103	return 0;
1104}
1105
1106/*
1107 * Look through the program headers of an executable image, searching
1108 * for a PT_INTERP section; if one is found, it's dynamically linked,
1109 * otherwise it's statically linked.
1110 */
1111private int
1112dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
1113    int num, size_t size, off_t fsize, int *flags, int sh_num)
1114{
1115	Elf32_Phdr ph32;
1116	Elf64_Phdr ph64;
1117	const char *linking_style = "statically";
1118	const char *shared_libraries = "";
1119	unsigned char nbuf[BUFSIZ];
1120	ssize_t bufsize;
1121	size_t offset, align, len;
1122
1123	if (size != xph_sizeof) {
1124		if (file_printf(ms, ", corrupted program header size") == -1)
1125			return -1;
1126		return 0;
1127	}
1128
1129  	for ( ; num; num--) {
1130		if (pread(fd, xph_addr, xph_sizeof, off) == -1) {
1131			file_badread(ms);
1132			return -1;
1133		}
1134
1135		off += size;
1136
1137		/* Things we can determine before we seek */
1138		switch (xph_type) {
1139		case PT_DYNAMIC:
1140			linking_style = "dynamically";
1141			break;
1142		case PT_INTERP:
1143			shared_libraries = " (uses shared libs)";
1144			break;
1145		default:
1146			if (xph_offset > fsize) {
1147				/* Maybe warn here? */
1148				continue;
1149			}
1150			break;
1151		}
1152
1153		/* Things we can determine when we seek */
1154		switch (xph_type) {
1155		case PT_NOTE:
1156			if ((align = xph_align) & 0x80000000UL) {
1157				if (file_printf(ms,
1158				    ", invalid note alignment 0x%lx",
1159				    (unsigned long)align) == -1)
1160					return -1;
1161				align = 4;
1162			}
1163			if (sh_num)
1164				break;
1165			/*
1166			 * This is a PT_NOTE section; loop through all the notes
1167			 * in the section.
1168			 */
1169			len = xph_filesz < sizeof(nbuf) ? xph_filesz
1170			    : sizeof(nbuf);
1171			bufsize = pread(fd, nbuf, len, xph_offset);
1172			if (bufsize == -1) {
1173				file_badread(ms);
1174				return -1;
1175			}
1176			offset = 0;
1177			for (;;) {
1178				if (offset >= (size_t)bufsize)
1179					break;
1180				offset = donote(ms, nbuf, offset,
1181				    (size_t)bufsize, clazz, swap, align,
1182				    flags);
1183				if (offset == 0)
1184					break;
1185			}
1186			break;
1187		default:
1188			break;
1189		}
1190	}
1191	if (file_printf(ms, ", %s linked%s", linking_style, shared_libraries)
1192	    == -1)
1193	    return -1;
1194	return 0;
1195}
1196
1197
1198protected int
1199file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
1200    size_t nbytes)
1201{
1202	union {
1203		int32_t l;
1204		char c[sizeof (int32_t)];
1205	} u;
1206	int clazz;
1207	int swap;
1208	struct stat st;
1209	off_t fsize;
1210	int flags = 0;
1211	Elf32_Ehdr elf32hdr;
1212	Elf64_Ehdr elf64hdr;
1213	uint16_t type;
1214
1215	if (ms->flags & (MAGIC_MIME|MAGIC_APPLE))
1216		return 0;
1217	/*
1218	 * ELF executables have multiple section headers in arbitrary
1219	 * file locations and thus file(1) cannot determine it from easily.
1220	 * Instead we traverse thru all section headers until a symbol table
1221	 * one is found or else the binary is stripped.
1222	 * Return immediately if it's not ELF (so we avoid pipe2file unless needed).
1223	 */
1224	if (buf[EI_MAG0] != ELFMAG0
1225	    || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
1226	    || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
1227		return 0;
1228
1229	/*
1230	 * If we cannot seek, it must be a pipe, socket or fifo.
1231	 */
1232	if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE))
1233		fd = file_pipe2file(ms, fd, buf, nbytes);
1234
1235	if (fstat(fd, &st) == -1) {
1236  		file_badread(ms);
1237		return -1;
1238	}
1239	fsize = st.st_size;
1240
1241	clazz = buf[EI_CLASS];
1242
1243	switch (clazz) {
1244	case ELFCLASS32:
1245#undef elf_getu
1246#define elf_getu(a, b)	elf_getu32(a, b)
1247#undef elfhdr
1248#define elfhdr elf32hdr
1249#include "elfclass.h"
1250	case ELFCLASS64:
1251#undef elf_getu
1252#define elf_getu(a, b)	elf_getu64(a, b)
1253#undef elfhdr
1254#define elfhdr elf64hdr
1255#include "elfclass.h"
1256	default:
1257	    if (file_printf(ms, ", unknown class %d", clazz) == -1)
1258		    return -1;
1259	    break;
1260	}
1261	return 0;
1262}
1263#endif
1264