xref: /freebsd/contrib/file/src/readelf.c (revision 617aa98c6c25406d90089351dbdf69d3a205f49d)
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 1.103 2014/05/02 02:25:10 christos Exp $")
31 #endif
32 
33 #ifdef BUILTIN_ELF
34 #include <string.h>
35 #include <ctype.h>
36 #include <stdlib.h>
37 #ifdef HAVE_UNISTD_H
38 #include <unistd.h>
39 #endif
40 
41 #include "readelf.h"
42 #include "magic.h"
43 
44 #ifdef	ELFCORE
45 private int dophn_core(struct magic_set *, int, int, int, off_t, int, size_t,
46     off_t, int *);
47 #endif
48 private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t,
49     off_t, int *, int);
50 private int doshn(struct magic_set *, int, int, int, off_t, int, size_t,
51     off_t, int *, int, int);
52 private size_t donote(struct magic_set *, void *, size_t, size_t, int,
53     int, size_t, int *);
54 
55 #define	ELF_ALIGN(a)	((((a) + align - 1) / align) * align)
56 
57 #define isquote(c) (strchr("'\"`", (c)) != NULL)
58 
59 private uint16_t getu16(int, uint16_t);
60 private uint32_t getu32(int, uint32_t);
61 private uint64_t getu64(int, uint64_t);
62 
63 private uint16_t
64 getu16(int swap, uint16_t value)
65 {
66 	union {
67 		uint16_t ui;
68 		char c[2];
69 	} retval, tmpval;
70 
71 	if (swap) {
72 		tmpval.ui = value;
73 
74 		retval.c[0] = tmpval.c[1];
75 		retval.c[1] = tmpval.c[0];
76 
77 		return retval.ui;
78 	} else
79 		return value;
80 }
81 
82 private uint32_t
83 getu32(int swap, uint32_t value)
84 {
85 	union {
86 		uint32_t ui;
87 		char c[4];
88 	} retval, tmpval;
89 
90 	if (swap) {
91 		tmpval.ui = value;
92 
93 		retval.c[0] = tmpval.c[3];
94 		retval.c[1] = tmpval.c[2];
95 		retval.c[2] = tmpval.c[1];
96 		retval.c[3] = tmpval.c[0];
97 
98 		return retval.ui;
99 	} else
100 		return value;
101 }
102 
103 private uint64_t
104 getu64(int swap, uint64_t value)
105 {
106 	union {
107 		uint64_t ui;
108 		char c[8];
109 	} retval, tmpval;
110 
111 	if (swap) {
112 		tmpval.ui = value;
113 
114 		retval.c[0] = tmpval.c[7];
115 		retval.c[1] = tmpval.c[6];
116 		retval.c[2] = tmpval.c[5];
117 		retval.c[3] = tmpval.c[4];
118 		retval.c[4] = tmpval.c[3];
119 		retval.c[5] = tmpval.c[2];
120 		retval.c[6] = tmpval.c[1];
121 		retval.c[7] = tmpval.c[0];
122 
123 		return retval.ui;
124 	} else
125 		return value;
126 }
127 
128 #define elf_getu16(swap, value) getu16(swap, value)
129 #define elf_getu32(swap, value) getu32(swap, value)
130 #define elf_getu64(swap, value) getu64(swap, value)
131 
132 #define xsh_addr	(clazz == ELFCLASS32			\
133 			 ? (void *)&sh32			\
134 			 : (void *)&sh64)
135 #define xsh_sizeof	(clazz == ELFCLASS32			\
136 			 ? sizeof(sh32)				\
137 			 : sizeof(sh64))
138 #define xsh_size	(size_t)(clazz == ELFCLASS32		\
139 			 ? elf_getu32(swap, sh32.sh_size)	\
140 			 : elf_getu64(swap, sh64.sh_size))
141 #define xsh_offset	(off_t)(clazz == ELFCLASS32		\
142 			 ? elf_getu32(swap, sh32.sh_offset)	\
143 			 : elf_getu64(swap, sh64.sh_offset))
144 #define xsh_type	(clazz == ELFCLASS32			\
145 			 ? elf_getu32(swap, sh32.sh_type)	\
146 			 : elf_getu32(swap, sh64.sh_type))
147 #define xsh_name    	(clazz == ELFCLASS32			\
148 			 ? elf_getu32(swap, sh32.sh_name)	\
149 			 : elf_getu32(swap, sh64.sh_name))
150 #define xph_addr	(clazz == ELFCLASS32			\
151 			 ? (void *) &ph32			\
152 			 : (void *) &ph64)
153 #define xph_sizeof	(clazz == ELFCLASS32			\
154 			 ? sizeof(ph32)				\
155 			 : sizeof(ph64))
156 #define xph_type	(clazz == ELFCLASS32			\
157 			 ? elf_getu32(swap, ph32.p_type)	\
158 			 : elf_getu32(swap, ph64.p_type))
159 #define xph_offset	(off_t)(clazz == ELFCLASS32		\
160 			 ? elf_getu32(swap, ph32.p_offset)	\
161 			 : elf_getu64(swap, ph64.p_offset))
162 #define xph_align	(size_t)((clazz == ELFCLASS32		\
163 			 ? (off_t) (ph32.p_align ? 		\
164 			    elf_getu32(swap, ph32.p_align) : 4) \
165 			 : (off_t) (ph64.p_align ?		\
166 			    elf_getu64(swap, ph64.p_align) : 4)))
167 #define xph_filesz	(size_t)((clazz == ELFCLASS32		\
168 			 ? elf_getu32(swap, ph32.p_filesz)	\
169 			 : elf_getu64(swap, ph64.p_filesz)))
170 #define xnh_addr	(clazz == ELFCLASS32			\
171 			 ? (void *)&nh32			\
172 			 : (void *)&nh64)
173 #define xph_memsz	(size_t)((clazz == ELFCLASS32		\
174 			 ? elf_getu32(swap, ph32.p_memsz)	\
175 			 : elf_getu64(swap, ph64.p_memsz)))
176 #define xnh_sizeof	(clazz == ELFCLASS32			\
177 			 ? sizeof nh32				\
178 			 : sizeof nh64)
179 #define xnh_type	(clazz == ELFCLASS32			\
180 			 ? elf_getu32(swap, nh32.n_type)	\
181 			 : elf_getu32(swap, nh64.n_type))
182 #define xnh_namesz	(clazz == ELFCLASS32			\
183 			 ? elf_getu32(swap, nh32.n_namesz)	\
184 			 : elf_getu32(swap, nh64.n_namesz))
185 #define xnh_descsz	(clazz == ELFCLASS32			\
186 			 ? elf_getu32(swap, nh32.n_descsz)	\
187 			 : elf_getu32(swap, nh64.n_descsz))
188 #define prpsoffsets(i)	(clazz == ELFCLASS32			\
189 			 ? prpsoffsets32[i]			\
190 			 : prpsoffsets64[i])
191 #define xcap_addr	(clazz == ELFCLASS32			\
192 			 ? (void *)&cap32			\
193 			 : (void *)&cap64)
194 #define xcap_sizeof	(clazz == ELFCLASS32			\
195 			 ? sizeof cap32				\
196 			 : sizeof cap64)
197 #define xcap_tag	(clazz == ELFCLASS32			\
198 			 ? elf_getu32(swap, cap32.c_tag)	\
199 			 : elf_getu64(swap, cap64.c_tag))
200 #define xcap_val	(clazz == ELFCLASS32			\
201 			 ? elf_getu32(swap, cap32.c_un.c_val)	\
202 			 : elf_getu64(swap, cap64.c_un.c_val))
203 
204 #ifdef ELFCORE
205 /*
206  * Try larger offsets first to avoid false matches
207  * from earlier data that happen to look like strings.
208  */
209 static const size_t	prpsoffsets32[] = {
210 #ifdef USE_NT_PSINFO
211 	104,		/* SunOS 5.x (command line) */
212 	88,		/* SunOS 5.x (short name) */
213 #endif /* USE_NT_PSINFO */
214 
215 	100,		/* SunOS 5.x (command line) */
216 	84,		/* SunOS 5.x (short name) */
217 
218 	44,		/* Linux (command line) */
219 	28,		/* Linux 2.0.36 (short name) */
220 
221 	8,		/* FreeBSD */
222 };
223 
224 static const size_t	prpsoffsets64[] = {
225 #ifdef USE_NT_PSINFO
226 	152,		/* SunOS 5.x (command line) */
227 	136,		/* SunOS 5.x (short name) */
228 #endif /* USE_NT_PSINFO */
229 
230 	136,		/* SunOS 5.x, 64-bit (command line) */
231 	120,		/* SunOS 5.x, 64-bit (short name) */
232 
233 	56,		/* Linux (command line) */
234 	40,             /* Linux (tested on core from 2.4.x, short name) */
235 
236 	16,		/* FreeBSD, 64-bit */
237 };
238 
239 #define	NOFFSETS32	(sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
240 #define NOFFSETS64	(sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
241 
242 #define NOFFSETS	(clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
243 
244 /*
245  * Look through the program headers of an executable image, searching
246  * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
247  * "FreeBSD"; if one is found, try looking in various places in its
248  * contents for a 16-character string containing only printable
249  * characters - if found, that string should be the name of the program
250  * that dropped core.  Note: right after that 16-character string is,
251  * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
252  * Linux, a longer string (80 characters, in 5.x, probably other
253  * SVR4-flavored systems, and Linux) containing the start of the
254  * command line for that program.
255  *
256  * SunOS 5.x core files contain two PT_NOTE sections, with the types
257  * NT_PRPSINFO (old) and NT_PSINFO (new).  These structs contain the
258  * same info about the command name and command line, so it probably
259  * isn't worthwhile to look for NT_PSINFO, but the offsets are provided
260  * above (see USE_NT_PSINFO), in case we ever decide to do so.  The
261  * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent;
262  * the SunOS 5.x file command relies on this (and prefers the latter).
263  *
264  * The signal number probably appears in a section of type NT_PRSTATUS,
265  * but that's also rather OS-dependent, in ways that are harder to
266  * dissect with heuristics, so I'm not bothering with the signal number.
267  * (I suppose the signal number could be of interest in situations where
268  * you don't have the binary of the program that dropped core; if you
269  * *do* have that binary, the debugger will probably tell you what
270  * signal it was.)
271  */
272 
273 #define	OS_STYLE_SVR4		0
274 #define	OS_STYLE_FREEBSD	1
275 #define	OS_STYLE_NETBSD		2
276 
277 private const char os_style_names[][8] = {
278 	"SVR4",
279 	"FreeBSD",
280 	"NetBSD",
281 };
282 
283 #define FLAGS_DID_CORE		0x01
284 #define FLAGS_DID_NOTE		0x02
285 #define FLAGS_DID_BUILD_ID	0x04
286 #define FLAGS_DID_CORE_STYLE	0x08
287 #define FLAGS_IS_CORE		0x10
288 
289 private int
290 dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
291     int num, size_t size, off_t fsize, int *flags)
292 {
293 	Elf32_Phdr ph32;
294 	Elf64_Phdr ph64;
295 	size_t offset, len;
296 	unsigned char nbuf[BUFSIZ];
297 	ssize_t bufsize;
298 
299 	if (size != xph_sizeof) {
300 		if (file_printf(ms, ", corrupted program header size") == -1)
301 			return -1;
302 		return 0;
303 	}
304 
305 	/*
306 	 * Loop through all the program headers.
307 	 */
308 	for ( ; num; num--) {
309 		if (pread(fd, xph_addr, xph_sizeof, off) == -1) {
310 			file_badread(ms);
311 			return -1;
312 		}
313 		off += size;
314 
315 		if (xph_offset > fsize) {
316 			/* Perhaps warn here */
317 			continue;
318 		}
319 
320 		if (xph_type != PT_NOTE)
321 			continue;
322 
323 		/*
324 		 * This is a PT_NOTE section; loop through all the notes
325 		 * in the section.
326 		 */
327 		len = xph_filesz < sizeof(nbuf) ? xph_filesz : sizeof(nbuf);
328 		if ((bufsize = pread(fd, nbuf, len, xph_offset)) == -1) {
329 			file_badread(ms);
330 			return -1;
331 		}
332 		offset = 0;
333 		for (;;) {
334 			if (offset >= (size_t)bufsize)
335 				break;
336 			offset = donote(ms, nbuf, offset, (size_t)bufsize,
337 			    clazz, swap, 4, flags);
338 			if (offset == 0)
339 				break;
340 
341 		}
342 	}
343 	return 0;
344 }
345 #endif
346 
347 static void
348 do_note_netbsd_version(struct magic_set *ms, int swap, void *v)
349 {
350 	uint32_t desc;
351 	(void)memcpy(&desc, v, sizeof(desc));
352 	desc = elf_getu32(swap, desc);
353 
354 	if (file_printf(ms, ", for NetBSD") == -1)
355 		return;
356 	/*
357 	 * The version number used to be stuck as 199905, and was thus
358 	 * basically content-free.  Newer versions of NetBSD have fixed
359 	 * this and now use the encoding of __NetBSD_Version__:
360 	 *
361 	 *	MMmmrrpp00
362 	 *
363 	 * M = major version
364 	 * m = minor version
365 	 * r = release ["",A-Z,Z[A-Z] but numeric]
366 	 * p = patchlevel
367 	 */
368 	if (desc > 100000000U) {
369 		uint32_t ver_patch = (desc / 100) % 100;
370 		uint32_t ver_rel = (desc / 10000) % 100;
371 		uint32_t ver_min = (desc / 1000000) % 100;
372 		uint32_t ver_maj = desc / 100000000;
373 
374 		if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1)
375 			return;
376 		if (ver_rel == 0 && ver_patch != 0) {
377 			if (file_printf(ms, ".%u", ver_patch) == -1)
378 				return;
379 		} else if (ver_rel != 0) {
380 			while (ver_rel > 26) {
381 				if (file_printf(ms, "Z") == -1)
382 					return;
383 				ver_rel -= 26;
384 			}
385 			if (file_printf(ms, "%c", 'A' + ver_rel - 1)
386 			    == -1)
387 				return;
388 		}
389 	}
390 }
391 
392 static void
393 do_note_freebsd_version(struct magic_set *ms, int swap, void *v)
394 {
395 	uint32_t desc;
396 
397 	(void)memcpy(&desc, v, sizeof(desc));
398 	desc = elf_getu32(swap, desc);
399 	if (file_printf(ms, ", for FreeBSD") == -1)
400 		return;
401 
402 	/*
403 	 * Contents is __FreeBSD_version, whose relation to OS
404 	 * versions is defined by a huge table in the Porter's
405 	 * Handbook.  This is the general scheme:
406 	 *
407 	 * Releases:
408 	 * 	Mmp000 (before 4.10)
409 	 * 	Mmi0p0 (before 5.0)
410 	 * 	Mmm0p0
411 	 *
412 	 * Development branches:
413 	 * 	Mmpxxx (before 4.6)
414 	 * 	Mmp1xx (before 4.10)
415 	 * 	Mmi1xx (before 5.0)
416 	 * 	M000xx (pre-M.0)
417 	 * 	Mmm1xx
418 	 *
419 	 * M = major version
420 	 * m = minor version
421 	 * i = minor version increment (491000 -> 4.10)
422 	 * p = patchlevel
423 	 * x = revision
424 	 *
425 	 * The first release of FreeBSD to use ELF by default
426 	 * was version 3.0.
427 	 */
428 	if (desc == 460002) {
429 		if (file_printf(ms, " 4.6.2") == -1)
430 			return;
431 	} else if (desc < 460100) {
432 		if (file_printf(ms, " %d.%d", desc / 100000,
433 		    desc / 10000 % 10) == -1)
434 			return;
435 		if (desc / 1000 % 10 > 0)
436 			if (file_printf(ms, ".%d", desc / 1000 % 10) == -1)
437 				return;
438 		if ((desc % 1000 > 0) || (desc % 100000 == 0))
439 			if (file_printf(ms, " (%d)", desc) == -1)
440 				return;
441 	} else if (desc < 500000) {
442 		if (file_printf(ms, " %d.%d", desc / 100000,
443 		    desc / 10000 % 10 + desc / 1000 % 10) == -1)
444 			return;
445 		if (desc / 100 % 10 > 0) {
446 			if (file_printf(ms, " (%d)", desc) == -1)
447 				return;
448 		} else if (desc / 10 % 10 > 0) {
449 			if (file_printf(ms, ".%d", desc / 10 % 10) == -1)
450 				return;
451 		}
452 	} else {
453 		if (file_printf(ms, " %d.%d", desc / 100000,
454 		    desc / 1000 % 100) == -1)
455 			return;
456 		if ((desc / 100 % 10 > 0) ||
457 		    (desc % 100000 / 100 == 0)) {
458 			if (file_printf(ms, " (%d)", desc) == -1)
459 				return;
460 		} else if (desc / 10 % 10 > 0) {
461 			if (file_printf(ms, ".%d", desc / 10 % 10) == -1)
462 				return;
463 		}
464 	}
465 }
466 
467 private size_t
468 donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
469     int clazz, int swap, size_t align, int *flags)
470 {
471 	Elf32_Nhdr nh32;
472 	Elf64_Nhdr nh64;
473 	size_t noff, doff;
474 #ifdef ELFCORE
475 	int os_style = -1;
476 #endif
477 	uint32_t namesz, descsz;
478 	unsigned char *nbuf = CAST(unsigned char *, vbuf);
479 
480 	(void)memcpy(xnh_addr, &nbuf[offset], xnh_sizeof);
481 	offset += xnh_sizeof;
482 
483 	namesz = xnh_namesz;
484 	descsz = xnh_descsz;
485 	if ((namesz == 0) && (descsz == 0)) {
486 		/*
487 		 * We're out of note headers.
488 		 */
489 		return (offset >= size) ? offset : size;
490 	}
491 
492 	if (namesz & 0x80000000) {
493 	    (void)file_printf(ms, ", bad note name size 0x%lx",
494 		(unsigned long)namesz);
495 	    return offset;
496 	}
497 
498 	if (descsz & 0x80000000) {
499 	    (void)file_printf(ms, ", bad note description size 0x%lx",
500 		(unsigned long)descsz);
501 	    return offset;
502 	}
503 
504 
505 	noff = offset;
506 	doff = ELF_ALIGN(offset + namesz);
507 
508 	if (offset + namesz > size) {
509 		/*
510 		 * We're past the end of the buffer.
511 		 */
512 		return doff;
513 	}
514 
515 	offset = ELF_ALIGN(doff + descsz);
516 	if (doff + descsz > size) {
517 		/*
518 		 * We're past the end of the buffer.
519 		 */
520 		return (offset >= size) ? offset : size;
521 	}
522 
523 	if ((*flags & (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID)) ==
524 	    (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID))
525 		goto core;
526 
527 	if (namesz == 5 && strcmp((char *)&nbuf[noff], "SuSE") == 0 &&
528 	    xnh_type == NT_GNU_VERSION && descsz == 2) {
529 	    file_printf(ms, ", for SuSE %d.%d", nbuf[doff], nbuf[doff + 1]);
530 	}
531 	if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
532 	    xnh_type == NT_GNU_VERSION && descsz == 16) {
533 		uint32_t desc[4];
534 		(void)memcpy(desc, &nbuf[doff], sizeof(desc));
535 
536 		if (file_printf(ms, ", for GNU/") == -1)
537 			return size;
538 		switch (elf_getu32(swap, desc[0])) {
539 		case GNU_OS_LINUX:
540 			if (file_printf(ms, "Linux") == -1)
541 				return size;
542 			break;
543 		case GNU_OS_HURD:
544 			if (file_printf(ms, "Hurd") == -1)
545 				return size;
546 			break;
547 		case GNU_OS_SOLARIS:
548 			if (file_printf(ms, "Solaris") == -1)
549 				return size;
550 			break;
551 		case GNU_OS_KFREEBSD:
552 			if (file_printf(ms, "kFreeBSD") == -1)
553 				return size;
554 			break;
555 		case GNU_OS_KNETBSD:
556 			if (file_printf(ms, "kNetBSD") == -1)
557 				return size;
558 			break;
559 		default:
560 			if (file_printf(ms, "<unknown>") == -1)
561 				return size;
562 		}
563 		if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]),
564 		    elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1)
565 			return size;
566 		*flags |= FLAGS_DID_NOTE;
567 		return size;
568 	}
569 
570 	if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
571 	    xnh_type == NT_GNU_BUILD_ID && (descsz == 16 || descsz == 20)) {
572 	    uint8_t desc[20];
573 	    uint32_t i;
574 	    if (file_printf(ms, ", BuildID[%s]=", descsz == 16 ? "md5/uuid" :
575 		"sha1") == -1)
576 		    return size;
577 	    (void)memcpy(desc, &nbuf[doff], descsz);
578 	    for (i = 0; i < descsz; i++)
579 		if (file_printf(ms, "%02x", desc[i]) == -1)
580 		    return size;
581 	    *flags |= FLAGS_DID_BUILD_ID;
582 	}
583 
584 	if (namesz == 4 && strcmp((char *)&nbuf[noff], "PaX") == 0 &&
585 	    xnh_type == NT_NETBSD_PAX && descsz == 4) {
586 		static const char *pax[] = {
587 		    "+mprotect",
588 		    "-mprotect",
589 		    "+segvguard",
590 		    "-segvguard",
591 		    "+ASLR",
592 		    "-ASLR",
593 		};
594 		uint32_t desc;
595 		size_t i;
596 		int did = 0;
597 
598 		(void)memcpy(&desc, &nbuf[doff], sizeof(desc));
599 		desc = elf_getu32(swap, desc);
600 
601 		if (desc && file_printf(ms, ", PaX: ") == -1)
602 			return size;
603 
604 		for (i = 0; i < __arraycount(pax); i++) {
605 			if (((1 << i) & desc) == 0)
606 				continue;
607 			if (file_printf(ms, "%s%s", did++ ? "," : "",
608 			    pax[i]) == -1)
609 				return size;
610 		}
611 	}
612 
613 	if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0) {
614 		switch (xnh_type) {
615 		case NT_NETBSD_VERSION:
616 			if (descsz == 4) {
617 				do_note_netbsd_version(ms, swap, &nbuf[doff]);
618 				*flags |= FLAGS_DID_NOTE;
619 				return size;
620 			}
621 			break;
622 		case NT_NETBSD_MARCH:
623 			if (file_printf(ms, ", compiled for: %.*s", (int)descsz,
624 			    (const char *)&nbuf[doff]) == -1)
625 				return size;
626 			break;
627 		case NT_NETBSD_CMODEL:
628 			if (file_printf(ms, ", compiler model: %.*s",
629 			    (int)descsz, (const char *)&nbuf[doff]) == -1)
630 				return size;
631 			break;
632 		default:
633 			if (file_printf(ms, ", note=%u", xnh_type) == -1)
634 				return size;
635 			break;
636 		}
637 		return size;
638 	}
639 
640 	if (namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0) {
641 	    	if (xnh_type == NT_FREEBSD_VERSION && descsz == 4) {
642 			do_note_freebsd_version(ms, swap, &nbuf[doff]);
643 			*flags |= FLAGS_DID_NOTE;
644 			return size;
645 		}
646 	}
647 
648 	if (namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 &&
649 	    xnh_type == NT_OPENBSD_VERSION && descsz == 4) {
650 		if (file_printf(ms, ", for OpenBSD") == -1)
651 			return size;
652 		/* Content of note is always 0 */
653 		*flags |= FLAGS_DID_NOTE;
654 		return size;
655 	}
656 
657 	if (namesz == 10 && strcmp((char *)&nbuf[noff], "DragonFly") == 0 &&
658 	    xnh_type == NT_DRAGONFLY_VERSION && descsz == 4) {
659 		uint32_t desc;
660 		if (file_printf(ms, ", for DragonFly") == -1)
661 			return size;
662 		(void)memcpy(&desc, &nbuf[doff], sizeof(desc));
663 		desc = elf_getu32(swap, desc);
664 		if (file_printf(ms, " %d.%d.%d", desc / 100000,
665 		    desc / 10000 % 10, desc % 10000) == -1)
666 			return size;
667 		*flags |= FLAGS_DID_NOTE;
668 		return size;
669 	}
670 
671 core:
672 	/*
673 	 * Sigh.  The 2.0.36 kernel in Debian 2.1, at
674 	 * least, doesn't correctly implement name
675 	 * sections, in core dumps, as specified by
676 	 * the "Program Linking" section of "UNIX(R) System
677 	 * V Release 4 Programmer's Guide: ANSI C and
678 	 * Programming Support Tools", because my copy
679 	 * clearly says "The first 'namesz' bytes in 'name'
680 	 * contain a *null-terminated* [emphasis mine]
681 	 * character representation of the entry's owner
682 	 * or originator", but the 2.0.36 kernel code
683 	 * doesn't include the terminating null in the
684 	 * name....
685 	 */
686 	if ((namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) ||
687 	    (namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) {
688 		os_style = OS_STYLE_SVR4;
689 	}
690 
691 	if ((namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) {
692 		os_style = OS_STYLE_FREEBSD;
693 	}
694 
695 	if ((namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11)
696 	    == 0)) {
697 		os_style = OS_STYLE_NETBSD;
698 	}
699 
700 #ifdef ELFCORE
701 	if ((*flags & FLAGS_DID_CORE) != 0)
702 		return size;
703 
704 	if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) {
705 		if (file_printf(ms, ", %s-style", os_style_names[os_style])
706 		    == -1)
707 			return size;
708 		*flags |= FLAGS_DID_CORE_STYLE;
709 	}
710 
711 	switch (os_style) {
712 	case OS_STYLE_NETBSD:
713 		if (xnh_type == NT_NETBSD_CORE_PROCINFO) {
714 			uint32_t signo;
715 			/*
716 			 * Extract the program name.  It is at
717 			 * offset 0x7c, and is up to 32-bytes,
718 			 * including the terminating NUL.
719 			 */
720 			if (file_printf(ms, ", from '%.31s'",
721 			    &nbuf[doff + 0x7c]) == -1)
722 				return size;
723 
724 			/*
725 			 * Extract the signal number.  It is at
726 			 * offset 0x08.
727 			 */
728 			(void)memcpy(&signo, &nbuf[doff + 0x08],
729 			    sizeof(signo));
730 			if (file_printf(ms, " (signal %u)",
731 			    elf_getu32(swap, signo)) == -1)
732 				return size;
733 			*flags |= FLAGS_DID_CORE;
734 			return size;
735 		}
736 		break;
737 
738 	default:
739 		if (xnh_type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) {
740 			size_t i, j;
741 			unsigned char c;
742 			/*
743 			 * Extract the program name.  We assume
744 			 * it to be 16 characters (that's what it
745 			 * is in SunOS 5.x and Linux).
746 			 *
747 			 * Unfortunately, it's at a different offset
748 			 * in various OSes, so try multiple offsets.
749 			 * If the characters aren't all printable,
750 			 * reject it.
751 			 */
752 			for (i = 0; i < NOFFSETS; i++) {
753 				unsigned char *cname, *cp;
754 				size_t reloffset = prpsoffsets(i);
755 				size_t noffset = doff + reloffset;
756 				size_t k;
757 				for (j = 0; j < 16; j++, noffset++,
758 				    reloffset++) {
759 					/*
760 					 * Make sure we're not past
761 					 * the end of the buffer; if
762 					 * we are, just give up.
763 					 */
764 					if (noffset >= size)
765 						goto tryanother;
766 
767 					/*
768 					 * Make sure we're not past
769 					 * the end of the contents;
770 					 * if we are, this obviously
771 					 * isn't the right offset.
772 					 */
773 					if (reloffset >= descsz)
774 						goto tryanother;
775 
776 					c = nbuf[noffset];
777 					if (c == '\0') {
778 						/*
779 						 * A '\0' at the
780 						 * beginning is
781 						 * obviously wrong.
782 						 * Any other '\0'
783 						 * means we're done.
784 						 */
785 						if (j == 0)
786 							goto tryanother;
787 						else
788 							break;
789 					} else {
790 						/*
791 						 * A nonprintable
792 						 * character is also
793 						 * wrong.
794 						 */
795 						if (!isprint(c) || isquote(c))
796 							goto tryanother;
797 					}
798 				}
799 				/*
800 				 * Well, that worked.
801 				 */
802 
803 				/*
804 				 * Try next offsets, in case this match is
805 				 * in the middle of a string.
806 				 */
807 				for (k = i + 1 ; k < NOFFSETS ; k++) {
808 					size_t no;
809 					int adjust = 1;
810 					if (prpsoffsets(k) >= prpsoffsets(i))
811 						continue;
812 					for (no = doff + prpsoffsets(k);
813 					     no < doff + prpsoffsets(i); no++)
814 						adjust = adjust
815 						         && isprint(nbuf[no]);
816 					if (adjust)
817 						i = k;
818 				}
819 
820 				cname = (unsigned char *)
821 				    &nbuf[doff + prpsoffsets(i)];
822 				for (cp = cname; *cp && isprint(*cp); cp++)
823 					continue;
824 				/*
825 				 * Linux apparently appends a space at the end
826 				 * of the command line: remove it.
827 				 */
828 				while (cp > cname && isspace(cp[-1]))
829 					cp--;
830 				if (file_printf(ms, ", from '%.*s'",
831 				    (int)(cp - cname), cname) == -1)
832 					return size;
833 				*flags |= FLAGS_DID_CORE;
834 				return size;
835 
836 			tryanother:
837 				;
838 			}
839 		}
840 		break;
841 	}
842 #endif
843 	return offset;
844 }
845 
846 /* SunOS 5.x hardware capability descriptions */
847 typedef struct cap_desc {
848 	uint64_t cd_mask;
849 	const char *cd_name;
850 } cap_desc_t;
851 
852 static const cap_desc_t cap_desc_sparc[] = {
853 	{ AV_SPARC_MUL32,		"MUL32" },
854 	{ AV_SPARC_DIV32,		"DIV32" },
855 	{ AV_SPARC_FSMULD,		"FSMULD" },
856 	{ AV_SPARC_V8PLUS,		"V8PLUS" },
857 	{ AV_SPARC_POPC,		"POPC" },
858 	{ AV_SPARC_VIS,			"VIS" },
859 	{ AV_SPARC_VIS2,		"VIS2" },
860 	{ AV_SPARC_ASI_BLK_INIT,	"ASI_BLK_INIT" },
861 	{ AV_SPARC_FMAF,		"FMAF" },
862 	{ AV_SPARC_FJFMAU,		"FJFMAU" },
863 	{ AV_SPARC_IMA,			"IMA" },
864 	{ 0, NULL }
865 };
866 
867 static const cap_desc_t cap_desc_386[] = {
868 	{ AV_386_FPU,			"FPU" },
869 	{ AV_386_TSC,			"TSC" },
870 	{ AV_386_CX8,			"CX8" },
871 	{ AV_386_SEP,			"SEP" },
872 	{ AV_386_AMD_SYSC,		"AMD_SYSC" },
873 	{ AV_386_CMOV,			"CMOV" },
874 	{ AV_386_MMX,			"MMX" },
875 	{ AV_386_AMD_MMX,		"AMD_MMX" },
876 	{ AV_386_AMD_3DNow,		"AMD_3DNow" },
877 	{ AV_386_AMD_3DNowx,		"AMD_3DNowx" },
878 	{ AV_386_FXSR,			"FXSR" },
879 	{ AV_386_SSE,			"SSE" },
880 	{ AV_386_SSE2,			"SSE2" },
881 	{ AV_386_PAUSE,			"PAUSE" },
882 	{ AV_386_SSE3,			"SSE3" },
883 	{ AV_386_MON,			"MON" },
884 	{ AV_386_CX16,			"CX16" },
885 	{ AV_386_AHF,			"AHF" },
886 	{ AV_386_TSCP,			"TSCP" },
887 	{ AV_386_AMD_SSE4A,		"AMD_SSE4A" },
888 	{ AV_386_POPCNT,		"POPCNT" },
889 	{ AV_386_AMD_LZCNT,		"AMD_LZCNT" },
890 	{ AV_386_SSSE3,			"SSSE3" },
891 	{ AV_386_SSE4_1,		"SSE4.1" },
892 	{ AV_386_SSE4_2,		"SSE4.2" },
893 	{ 0, NULL }
894 };
895 
896 private int
897 doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
898     size_t size, off_t fsize, int *flags, int mach, int strtab)
899 {
900 	Elf32_Shdr sh32;
901 	Elf64_Shdr sh64;
902 	int stripped = 1;
903 	void *nbuf;
904 	off_t noff, coff, name_off;
905 	uint64_t cap_hw1 = 0;	/* SunOS 5.x hardware capabilites */
906 	uint64_t cap_sf1 = 0;	/* SunOS 5.x software capabilites */
907 	char name[50];
908 
909 	if (size != xsh_sizeof) {
910 		if (file_printf(ms, ", corrupted section header size") == -1)
911 			return -1;
912 		return 0;
913 	}
914 
915 	/* Read offset of name section to be able to read section names later */
916 	if (pread(fd, xsh_addr, xsh_sizeof, off + size * strtab) == -1) {
917 		file_badread(ms);
918 		return -1;
919 	}
920 	name_off = xsh_offset;
921 
922 	for ( ; num; num--) {
923 		/* Read the name of this section. */
924 		if (pread(fd, name, sizeof(name), name_off + xsh_name) == -1) {
925 			file_badread(ms);
926 			return -1;
927 		}
928 		name[sizeof(name) - 1] = '\0';
929 		if (strcmp(name, ".debug_info") == 0)
930 			stripped = 0;
931 
932 		if (pread(fd, xsh_addr, xsh_sizeof, off) == -1) {
933 			file_badread(ms);
934 			return -1;
935 		}
936 		off += size;
937 
938 		/* Things we can determine before we seek */
939 		switch (xsh_type) {
940 		case SHT_SYMTAB:
941 #if 0
942 		case SHT_DYNSYM:
943 #endif
944 			stripped = 0;
945 			break;
946 		default:
947 			if (xsh_offset > fsize) {
948 				/* Perhaps warn here */
949 				continue;
950 			}
951 			break;
952 		}
953 
954 		/* Things we can determine when we seek */
955 		switch (xsh_type) {
956 		case SHT_NOTE:
957 			if ((nbuf = malloc(xsh_size)) == NULL) {
958 				file_error(ms, errno, "Cannot allocate memory"
959 				    " for note");
960 				return -1;
961 			}
962 			if (pread(fd, nbuf, xsh_size, xsh_offset) == -1) {
963 				file_badread(ms);
964 				free(nbuf);
965 				return -1;
966 			}
967 
968 			noff = 0;
969 			for (;;) {
970 				if (noff >= (off_t)xsh_size)
971 					break;
972 				noff = donote(ms, nbuf, (size_t)noff,
973 				    xsh_size, clazz, swap, 4, flags);
974 				if (noff == 0)
975 					break;
976 			}
977 			free(nbuf);
978 			break;
979 		case SHT_SUNW_cap:
980 			switch (mach) {
981 			case EM_SPARC:
982 			case EM_SPARCV9:
983 			case EM_IA_64:
984 			case EM_386:
985 			case EM_AMD64:
986 				break;
987 			default:
988 				goto skip;
989 			}
990 
991 			if (lseek(fd, xsh_offset, SEEK_SET) == (off_t)-1) {
992 				file_badseek(ms);
993 				return -1;
994 			}
995 			coff = 0;
996 			for (;;) {
997 				Elf32_Cap cap32;
998 				Elf64_Cap cap64;
999 				char cbuf[/*CONSTCOND*/
1000 				    MAX(sizeof cap32, sizeof cap64)];
1001 				if ((coff += xcap_sizeof) > (off_t)xsh_size)
1002 					break;
1003 				if (read(fd, cbuf, (size_t)xcap_sizeof) !=
1004 				    (ssize_t)xcap_sizeof) {
1005 					file_badread(ms);
1006 					return -1;
1007 				}
1008 				if (cbuf[0] == 'A') {
1009 #ifdef notyet
1010 					char *p = cbuf + 1;
1011 					uint32_t len, tag;
1012 					memcpy(&len, p, sizeof(len));
1013 					p += 4;
1014 					len = getu32(swap, len);
1015 					if (memcmp("gnu", p, 3) != 0) {
1016 					    if (file_printf(ms,
1017 						", unknown capability %.3s", p)
1018 						== -1)
1019 						return -1;
1020 					    break;
1021 					}
1022 					p += strlen(p) + 1;
1023 					tag = *p++;
1024 					memcpy(&len, p, sizeof(len));
1025 					p += 4;
1026 					len = getu32(swap, len);
1027 					if (tag != 1) {
1028 					    if (file_printf(ms, ", unknown gnu"
1029 						" capability tag %d", tag)
1030 						== -1)
1031 						return -1;
1032 					    break;
1033 					}
1034 					// gnu attributes
1035 #endif
1036 					break;
1037 				}
1038 				(void)memcpy(xcap_addr, cbuf, xcap_sizeof);
1039 				switch (xcap_tag) {
1040 				case CA_SUNW_NULL:
1041 					break;
1042 				case CA_SUNW_HW_1:
1043 					cap_hw1 |= xcap_val;
1044 					break;
1045 				case CA_SUNW_SF_1:
1046 					cap_sf1 |= xcap_val;
1047 					break;
1048 				default:
1049 					if (file_printf(ms,
1050 					    ", with unknown capability "
1051 					    "0x%" INT64_T_FORMAT "x = 0x%"
1052 					    INT64_T_FORMAT "x",
1053 					    (unsigned long long)xcap_tag,
1054 					    (unsigned long long)xcap_val) == -1)
1055 						return -1;
1056 					break;
1057 				}
1058 			}
1059 			/*FALLTHROUGH*/
1060 		skip:
1061 		default:
1062 			break;
1063 		}
1064 	}
1065 
1066 	if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1)
1067 		return -1;
1068 	if (cap_hw1) {
1069 		const cap_desc_t *cdp;
1070 		switch (mach) {
1071 		case EM_SPARC:
1072 		case EM_SPARC32PLUS:
1073 		case EM_SPARCV9:
1074 			cdp = cap_desc_sparc;
1075 			break;
1076 		case EM_386:
1077 		case EM_IA_64:
1078 		case EM_AMD64:
1079 			cdp = cap_desc_386;
1080 			break;
1081 		default:
1082 			cdp = NULL;
1083 			break;
1084 		}
1085 		if (file_printf(ms, ", uses") == -1)
1086 			return -1;
1087 		if (cdp) {
1088 			while (cdp->cd_name) {
1089 				if (cap_hw1 & cdp->cd_mask) {
1090 					if (file_printf(ms,
1091 					    " %s", cdp->cd_name) == -1)
1092 						return -1;
1093 					cap_hw1 &= ~cdp->cd_mask;
1094 				}
1095 				++cdp;
1096 			}
1097 			if (cap_hw1)
1098 				if (file_printf(ms,
1099 				    " unknown hardware capability 0x%"
1100 				    INT64_T_FORMAT "x",
1101 				    (unsigned long long)cap_hw1) == -1)
1102 					return -1;
1103 		} else {
1104 			if (file_printf(ms,
1105 			    " hardware capability 0x%" INT64_T_FORMAT "x",
1106 			    (unsigned long long)cap_hw1) == -1)
1107 				return -1;
1108 		}
1109 	}
1110 	if (cap_sf1) {
1111 		if (cap_sf1 & SF1_SUNW_FPUSED) {
1112 			if (file_printf(ms,
1113 			    (cap_sf1 & SF1_SUNW_FPKNWN)
1114 			    ? ", uses frame pointer"
1115 			    : ", not known to use frame pointer") == -1)
1116 				return -1;
1117 		}
1118 		cap_sf1 &= ~SF1_SUNW_MASK;
1119 		if (cap_sf1)
1120 			if (file_printf(ms,
1121 			    ", with unknown software capability 0x%"
1122 			    INT64_T_FORMAT "x",
1123 			    (unsigned long long)cap_sf1) == -1)
1124 				return -1;
1125 	}
1126 	return 0;
1127 }
1128 
1129 /*
1130  * Look through the program headers of an executable image, searching
1131  * for a PT_INTERP section; if one is found, it's dynamically linked,
1132  * otherwise it's statically linked.
1133  */
1134 private int
1135 dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
1136     int num, size_t size, off_t fsize, int *flags, int sh_num)
1137 {
1138 	Elf32_Phdr ph32;
1139 	Elf64_Phdr ph64;
1140 	const char *linking_style = "statically";
1141 	const char *shared_libraries = "";
1142 	unsigned char nbuf[BUFSIZ];
1143 	ssize_t bufsize;
1144 	size_t offset, align, len;
1145 
1146 	if (size != xph_sizeof) {
1147 		if (file_printf(ms, ", corrupted program header size") == -1)
1148 			return -1;
1149 		return 0;
1150 	}
1151 
1152   	for ( ; num; num--) {
1153 		if (pread(fd, xph_addr, xph_sizeof, off) == -1) {
1154 			file_badread(ms);
1155 			return -1;
1156 		}
1157 
1158 		off += size;
1159 
1160 		/* Things we can determine before we seek */
1161 		switch (xph_type) {
1162 		case PT_DYNAMIC:
1163 			linking_style = "dynamically";
1164 			break;
1165 		case PT_INTERP:
1166 			shared_libraries = " (uses shared libs)";
1167 			break;
1168 		default:
1169 			if (xph_offset > fsize) {
1170 				/* Maybe warn here? */
1171 				continue;
1172 			}
1173 			break;
1174 		}
1175 
1176 		/* Things we can determine when we seek */
1177 		switch (xph_type) {
1178 		case PT_NOTE:
1179 			if ((align = xph_align) & 0x80000000UL) {
1180 				if (file_printf(ms,
1181 				    ", invalid note alignment 0x%lx",
1182 				    (unsigned long)align) == -1)
1183 					return -1;
1184 				align = 4;
1185 			}
1186 			if (sh_num)
1187 				break;
1188 			/*
1189 			 * This is a PT_NOTE section; loop through all the notes
1190 			 * in the section.
1191 			 */
1192 			len = xph_filesz < sizeof(nbuf) ? xph_filesz
1193 			    : sizeof(nbuf);
1194 			bufsize = pread(fd, nbuf, len, xph_offset);
1195 			if (bufsize == -1) {
1196 				file_badread(ms);
1197 				return -1;
1198 			}
1199 			offset = 0;
1200 			for (;;) {
1201 				if (offset >= (size_t)bufsize)
1202 					break;
1203 				offset = donote(ms, nbuf, offset,
1204 				    (size_t)bufsize, clazz, swap, align,
1205 				    flags);
1206 				if (offset == 0)
1207 					break;
1208 			}
1209 			break;
1210 		default:
1211 			break;
1212 		}
1213 	}
1214 	if (file_printf(ms, ", %s linked%s", linking_style, shared_libraries)
1215 	    == -1)
1216 	    return -1;
1217 	return 0;
1218 }
1219 
1220 
1221 protected int
1222 file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
1223     size_t nbytes)
1224 {
1225 	union {
1226 		int32_t l;
1227 		char c[sizeof (int32_t)];
1228 	} u;
1229 	int clazz;
1230 	int swap;
1231 	struct stat st;
1232 	off_t fsize;
1233 	int flags = 0;
1234 	Elf32_Ehdr elf32hdr;
1235 	Elf64_Ehdr elf64hdr;
1236 	uint16_t type;
1237 
1238 	if (ms->flags & (MAGIC_MIME|MAGIC_APPLE))
1239 		return 0;
1240 	/*
1241 	 * ELF executables have multiple section headers in arbitrary
1242 	 * file locations and thus file(1) cannot determine it from easily.
1243 	 * Instead we traverse thru all section headers until a symbol table
1244 	 * one is found or else the binary is stripped.
1245 	 * Return immediately if it's not ELF (so we avoid pipe2file unless needed).
1246 	 */
1247 	if (buf[EI_MAG0] != ELFMAG0
1248 	    || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
1249 	    || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
1250 		return 0;
1251 
1252 	/*
1253 	 * If we cannot seek, it must be a pipe, socket or fifo.
1254 	 */
1255 	if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE))
1256 		fd = file_pipe2file(ms, fd, buf, nbytes);
1257 
1258 	if (fstat(fd, &st) == -1) {
1259   		file_badread(ms);
1260 		return -1;
1261 	}
1262 	fsize = st.st_size;
1263 
1264 	clazz = buf[EI_CLASS];
1265 
1266 	switch (clazz) {
1267 	case ELFCLASS32:
1268 #undef elf_getu
1269 #define elf_getu(a, b)	elf_getu32(a, b)
1270 #undef elfhdr
1271 #define elfhdr elf32hdr
1272 #include "elfclass.h"
1273 	case ELFCLASS64:
1274 #undef elf_getu
1275 #define elf_getu(a, b)	elf_getu64(a, b)
1276 #undef elfhdr
1277 #define elfhdr elf64hdr
1278 #include "elfclass.h"
1279 	default:
1280 	    if (file_printf(ms, ", unknown class %d", clazz) == -1)
1281 		    return -1;
1282 	    break;
1283 	}
1284 	return 0;
1285 }
1286 #endif
1287