aboutsummaryrefslogtreecommitdiff
blob: 2bafda40bec8899941211ae3f593f78359b8438e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
/*
 * Copyright 2003-2012 Gentoo Foundation
 * Distributed under the terms of the GNU General Public License v2
 *
 * Copyright 2005-2012 Ned Ludd        - <solar@gentoo.org>
 * Copyright 2005-2012 Mike Frysinger  - <vapier@gentoo.org>
 */

#include "paxinc.h"

/*
 * Setup a bunch of helper functions to translate
 * binary defines into readable strings.
 */
#define QUERY(n) { #n, n }
typedef const struct {
	const char *str;
	int value;
} pairtype;
static inline const char *find_pairtype(pairtype *pt, int type)
{
	int i;
	for (i = 0; pt[i].str; ++i)
		if (type == pt[i].value)
			return pt[i].str;
	return "UNKNOWN_TYPE";
}

/* translate misc elf EI_ defines */
static pairtype elf_ei_class[] = {
	QUERY(ELFCLASSNONE),
	QUERY(ELFCLASS32),
	QUERY(ELFCLASS64),
	{ 0, 0 }
};
static pairtype elf_ei_data[] = {
	QUERY(ELFDATANONE),
	QUERY(ELFDATA2LSB),
	QUERY(ELFDATA2MSB),
	{ 0, 0 }
};
static pairtype elf_ei_version[] = {
	QUERY(EV_NONE),
	QUERY(EV_CURRENT),
	{ 0, 0 }
};
static pairtype elf_ei_osabi[] = {
	QUERY(ELFOSABI_NONE),
	QUERY(ELFOSABI_SYSV),
	QUERY(ELFOSABI_HPUX),
	QUERY(ELFOSABI_NETBSD),
	QUERY(ELFOSABI_GNU),
	QUERY(ELFOSABI_LINUX),
	QUERY(ELFOSABI_SOLARIS),
	QUERY(ELFOSABI_AIX),
	QUERY(ELFOSABI_IRIX),
	QUERY(ELFOSABI_FREEBSD),
	QUERY(ELFOSABI_TRU64),
	QUERY(ELFOSABI_MODESTO),
	QUERY(ELFOSABI_OPENBSD),
	QUERY(ELFOSABI_ARM_AEABI),
	QUERY(ELFOSABI_ARM),
	QUERY(ELFOSABI_STANDALONE),
	{ 0, 0 }
};
const char *get_elfeitype(int ei_type, int type)
{
	switch (ei_type) {
		case EI_CLASS:   return find_pairtype(elf_ei_class, type);
		case EI_DATA:    return find_pairtype(elf_ei_data, type);
		case EI_VERSION: return find_pairtype(elf_ei_version, type);
		case EI_OSABI:   return find_pairtype(elf_ei_osabi, type);
	}
	return "UNKNOWN_EI_TYPE";
}

/* translate elf ET_ defines */
static pairtype elf_etypes[] = {
	QUERY(ET_NONE),
	QUERY(ET_REL),
	QUERY(ET_EXEC),
	QUERY(ET_DYN),
	QUERY(ET_CORE),
	{ 0, 0 }
};

int get_etype(elfobj *elf)
{
	int type;
	if (elf->elf_class == ELFCLASS32)
		type = EGET(EHDR32(elf->ehdr)->e_type);
	else
		type = EGET(EHDR64(elf->ehdr)->e_type);
	return type;
}

const char *get_elfetype(elfobj *elf)
{
	return find_pairtype(elf_etypes, get_etype(elf));
}

const char *get_endian(elfobj *elf)
{
	switch (elf->data[EI_DATA]) {
		case ELFDATA2LSB: return "LE";
		case ELFDATA2MSB: return "BE";
		default:          return "??";
	}
}

static int arm_eabi_poker(elfobj *elf)
{
	unsigned int emachine, eflags;

	if (ELFOSABI_NONE != elf->data[EI_OSABI])
		return -1;

	if (elf->elf_class == ELFCLASS32) {
		emachine = EHDR32(elf->ehdr)->e_machine;
		eflags = EHDR32(elf->ehdr)->e_flags;
	} else {
		emachine = EHDR64(elf->ehdr)->e_machine;
		eflags = EHDR64(elf->ehdr)->e_flags;
	}

	if (EGET(emachine) == EM_ARM)
		return EF_ARM_EABI_VERSION(EGET(eflags)) >> 24;
	else
		return -1;
}

const char *get_elf_eabi(elfobj *elf)
{
	static char buf[26];
	int eabi = arm_eabi_poker(elf);
	if (eabi >= 0)
		snprintf(buf, sizeof(buf), "%i", eabi);
	else
		strcpy(buf, "?");
	return buf;
}

const char *get_elfosabi(elfobj *elf)
{
	const char *str = get_elfeitype(EI_OSABI, elf->data[EI_OSABI]);
	if (strncmp(str, "ELFOSABI_", 9) == 0)
		str += 9;
	return str;
}

void print_etypes(FILE *stream)
{
	int i, wrap = 0;
	for (i = 0; elf_etypes[i].str; ++i) {
		fprintf(stream, " (%4x) = %-10s", elf_etypes[i].value, elf_etypes[i].str);
		if (++wrap >= 4) {
			fprintf(stream, "\n");
			wrap = 0;
		}
	}
	if (wrap)
		fprintf(stream, "\n");
}

int etype_lookup(const char *str)
{
	if (*str == 'E') {
		int i;
		for (i = 0; elf_etypes[i].str; ++i) {
			if (strcmp(str, elf_etypes[i].str) == 0)
				return elf_etypes[i].value;
		}
	}
	return atoi(str);
}

/* translate elf EM_ defines */
static pairtype elf_emtypes[] = {
	QUERY(EM_NONE),
	QUERY(EM_M32),
	QUERY(EM_SPARC),
	QUERY(EM_386),
	QUERY(EM_68K),
	QUERY(EM_88K),
	QUERY(EM_860),
	QUERY(EM_MIPS),
	QUERY(EM_S370),
	QUERY(EM_MIPS_RS3_LE),
	QUERY(EM_PARISC),
	QUERY(EM_VPP500),
	QUERY(EM_SPARC32PLUS),
	QUERY(EM_960),
	QUERY(EM_PPC),
	QUERY(EM_PPC64),
	QUERY(EM_S390),
	QUERY(EM_V800),
	QUERY(EM_FR20),
	QUERY(EM_RH32),
	QUERY(EM_RCE),
	QUERY(EM_ARM),
	QUERY(EM_FAKE_ALPHA),
	QUERY(EM_SH),
	QUERY(EM_SPARCV9),
	QUERY(EM_TRICORE),
	QUERY(EM_ARC),
	QUERY(EM_H8_300),
	QUERY(EM_H8_300H),
	QUERY(EM_H8S),
	QUERY(EM_H8_500),
	QUERY(EM_IA_64),
	QUERY(EM_MIPS_X),
	QUERY(EM_COLDFIRE),
	QUERY(EM_68HC12),
	QUERY(EM_MMA),
	QUERY(EM_PCP),
	QUERY(EM_NCPU),
	QUERY(EM_NDR1),
	QUERY(EM_STARCORE),
	QUERY(EM_ME16),
	QUERY(EM_ST100),
	QUERY(EM_TINYJ),
	QUERY(EM_X86_64),
	QUERY(EM_PDSP),
	QUERY(EM_FX66),
	QUERY(EM_ST9PLUS),
	QUERY(EM_ST7),
	QUERY(EM_68HC16),
	QUERY(EM_68HC11),
	QUERY(EM_68HC08),
	QUERY(EM_68HC05),
	QUERY(EM_SVX),
	QUERY(EM_ST19),
	QUERY(EM_VAX),
	QUERY(EM_CRIS),
	QUERY(EM_JAVELIN),
	QUERY(EM_FIREPATH),
	QUERY(EM_ZSP),
	QUERY(EM_MMIX),
	QUERY(EM_HUANY),
	QUERY(EM_PRISM),
	QUERY(EM_AVR),
	QUERY(EM_FR30),
	QUERY(EM_D10V),
	QUERY(EM_D30V),
	QUERY(EM_V850),
	QUERY(EM_M32R),
	QUERY(EM_MN10300),
	QUERY(EM_MN10200),
	QUERY(EM_PJ),
	QUERY(EM_OPENRISC),
	QUERY(EM_ARC_A5),
	QUERY(EM_XTENSA),
	QUERY(EM_VIDEOCORE),
	QUERY(EM_TMM_GPP),
	QUERY(EM_NS32K),
	QUERY(EM_TPC),
	QUERY(EM_SNP1K),
	QUERY(EM_ST200),
	QUERY(EM_IP2K),
	QUERY(EM_MAX),
	QUERY(EM_CR),
	QUERY(EM_F2MC16),
	QUERY(EM_MSP430),
	QUERY(EM_BLACKFIN),
	QUERY(EM_SE_C33),
	QUERY(EM_SEP),
	QUERY(EM_ARCA),
	QUERY(EM_UNICORE),
	QUERY(EM_ALTERA_NIOS2),
	QUERY(EM_AARCH64),
	QUERY(EM_TILEPRO),
	QUERY(EM_MICROBLAZE),
	QUERY(EM_TILEGX),
	QUERY(EM_ALPHA),
	{ 0, 0 }
};

int get_emtype(elfobj *elf)
{
	int type;
	if (elf->elf_class == ELFCLASS32)
		type = EGET(EHDR32(elf->ehdr)->e_machine);
	else
		type = EGET(EHDR64(elf->ehdr)->e_machine);
	return type;
}

const char *get_elfemtype(elfobj *elf)
{
	return find_pairtype(elf_emtypes, get_emtype(elf));
}

/* translate elf PT_ defines */
static pairtype elf_ptypes[] = {
	QUERY(PT_NULL),
	QUERY(PT_LOAD),
	QUERY(PT_DYNAMIC),
	QUERY(PT_INTERP),
	QUERY(PT_NOTE),
	QUERY(PT_SHLIB),
	QUERY(PT_PHDR),
	QUERY(PT_TLS),
	QUERY(PT_GNU_EH_FRAME),
	QUERY(PT_GNU_STACK),
	QUERY(PT_GNU_RELRO),
	QUERY(PT_PAX_FLAGS),
	{ 0, 0 }
};
const char *get_elfptype(int type)
{
	return find_pairtype(elf_ptypes, type);
}

/* translate elf PT_ defines */
static pairtype elf_dtypes[] = {
	QUERY(DT_NULL),
	QUERY(DT_NEEDED),
	QUERY(DT_PLTRELSZ),
	QUERY(DT_PLTGOT),
	QUERY(DT_HASH),
	QUERY(DT_STRTAB),
	QUERY(DT_SYMTAB),
	QUERY(DT_RELA),
	QUERY(DT_RELASZ),
	QUERY(DT_RELAENT),
	QUERY(DT_STRSZ),
	QUERY(DT_SYMENT),
	QUERY(DT_INIT),
	QUERY(DT_FINI),
	QUERY(DT_SONAME),
	QUERY(DT_RPATH),
	QUERY(DT_SYMBOLIC),
	QUERY(DT_REL),
	QUERY(DT_RELSZ),
	QUERY(DT_RELENT),
	QUERY(DT_PLTREL),
	QUERY(DT_DEBUG),
	QUERY(DT_TEXTREL),
	QUERY(DT_JMPREL),
	QUERY(DT_BIND_NOW),
	QUERY(DT_INIT_ARRAY),
	QUERY(DT_FINI_ARRAY),
	QUERY(DT_INIT_ARRAYSZ),
	QUERY(DT_FINI_ARRAYSZ),
	QUERY(DT_RUNPATH),
	QUERY(DT_FLAGS),
	QUERY(DT_ENCODING),
	QUERY(DT_PREINIT_ARRAY),
	QUERY(DT_PREINIT_ARRAYSZ),
	QUERY(DT_GNU_PRELINKED),
	QUERY(DT_GNU_CONFLICTSZ),
	QUERY(DT_GNU_LIBLISTSZ),
	QUERY(DT_CHECKSUM),
	QUERY(DT_PLTPADSZ),
	QUERY(DT_MOVEENT),
	QUERY(DT_MOVESZ),
	QUERY(DT_GNU_HASH),
	QUERY(DT_TLSDESC_PLT),
	QUERY(DT_TLSDESC_GOT),
	QUERY(DT_GNU_CONFLICT),
	QUERY(DT_GNU_LIBLIST),
	QUERY(DT_CONFIG),
	QUERY(DT_DEPAUDIT),
	QUERY(DT_AUDIT),
	QUERY(DT_PLTPAD),
	QUERY(DT_MOVETAB),
	QUERY(DT_SYMINFO),
	QUERY(DT_VERSYM),
	QUERY(DT_RELACOUNT),
	QUERY(DT_RELCOUNT),
	QUERY(DT_FLAGS_1),
	QUERY(DT_VERDEF),
	QUERY(DT_VERDEFNUM),
	QUERY(DT_VERNEED),
	QUERY(DT_VERNEEDNUM),
	QUERY(DT_AUXILIARY),
	QUERY(DT_FILTER),
	{ 0, 0 }
};
const char *get_elfdtype(int type)
{
	return find_pairtype(elf_dtypes, type);
}

/* translate elf SHT_ defines */
static pairtype elf_shttypes[] = {
	QUERY(SHT_NULL),
	QUERY(SHT_PROGBITS),
	QUERY(SHT_SYMTAB),
	QUERY(SHT_STRTAB),
	QUERY(SHT_RELA),
	QUERY(SHT_HASH),
	QUERY(SHT_DYNAMIC),
	QUERY(SHT_NOTE),
	QUERY(SHT_NOBITS),
	QUERY(SHT_REL),
	QUERY(SHT_SHLIB),
	QUERY(SHT_DYNSYM),
	QUERY(SHT_INIT_ARRAY),
	QUERY(SHT_FINI_ARRAY),
	QUERY(SHT_PREINIT_ARRAY),
	QUERY(SHT_GROUP),
	QUERY(SHT_SYMTAB_SHNDX),
	QUERY(SHT_GNU_ATTRIBUTES),
	QUERY(SHT_GNU_HASH),
	QUERY(SHT_GNU_LIBLIST),
	QUERY(SHT_CHECKSUM),
	QUERY(SHT_SUNW_move),
	QUERY(SHT_SUNW_COMDAT),
	QUERY(SHT_SUNW_syminfo),
	QUERY(SHT_GNU_verdef),
	QUERY(SHT_GNU_verneed),
	QUERY(SHT_GNU_versym),
	{ 0, 0 }
};
const char *get_elfshttype(int type)
{
	return find_pairtype(elf_shttypes, type);
}

/* translate elf STT_ defines */
static pairtype elf_stttypes[] = {
	QUERY(STT_NOTYPE),
	QUERY(STT_OBJECT),
	QUERY(STT_FUNC),
	QUERY(STT_SECTION),
	QUERY(STT_FILE),
	QUERY(STT_COMMON),
	QUERY(STT_TLS),
	QUERY(STT_GNU_IFUNC),
	{ 0, 0 }
};
const char *get_elfstttype(int type)
{
	return find_pairtype(elf_stttypes, type);
}

/* translate elf STB_ defines */
static pairtype elf_stbtypes[] = {
	QUERY(STB_LOCAL),
	QUERY(STB_GLOBAL),
	QUERY(STB_WEAK),
	QUERY(STB_GNU_UNIQUE),
	{ 0, 0 }
};
const char *get_elfstbtype(int type)
{
	return find_pairtype(elf_stbtypes, type);
}

/* translate elf STV_ defines */
static pairtype elf_stvtypes[] = {
	QUERY(STV_DEFAULT),
	QUERY(STV_INTERNAL),
	QUERY(STV_HIDDEN),
	QUERY(STV_PROTECTED),
	{ 0, 0 }
};
const char *get_elfstvtype(int type)
{
	return find_pairtype(elf_stvtypes, type);
}

/* translate elf SHN_ defines */
static pairtype elf_shntypes[] = {
	QUERY(SHN_UNDEF),
	QUERY(SHN_BEFORE),
	QUERY(SHN_AFTER),
	QUERY(SHN_ABS),
	QUERY(SHN_COMMON),
	QUERY(SHN_XINDEX),
	{ 0, 0 }
};
const char *get_elfshntype(int type)
{
	if (type && type < SHN_LORESERVE)
		return "DEFINED";
	return find_pairtype(elf_shntypes, type);
}

/* Read an ELF into memory */
#define IS_ELF_BUFFER(buff) \
	(buff[EI_MAG0] == ELFMAG0 && \
	 buff[EI_MAG1] == ELFMAG1 && \
	 buff[EI_MAG2] == ELFMAG2 && \
	 buff[EI_MAG3] == ELFMAG3)
#define DO_WE_LIKE_ELF(buff) \
	((buff[EI_CLASS] == ELFCLASS32 || buff[EI_CLASS] == ELFCLASS64) && \
	 (buff[EI_DATA] == ELFDATA2LSB || buff[EI_DATA] == ELFDATA2MSB) && \
	 (buff[EI_VERSION] == EV_CURRENT))
elfobj *readelf_buffer(const char *filename, void *buffer, size_t buffer_len)
{
	elfobj *elf;

	/* make sure we have enough bytes to scan e_ident */
	if (buffer == NULL || buffer_len < EI_NIDENT)
		return NULL;

	elf = xzalloc(sizeof(*elf));

	elf->fd = -1;
	elf->len = buffer_len;
	elf->data = buffer;
	elf->data_end = buffer + buffer_len;

	/* make sure we have an elf */
	if (!IS_ELF_BUFFER(elf->data)) {
free_elf_and_return:
		free(elf);
		return NULL;
	}

	/* check class and stuff */
	if (!DO_WE_LIKE_ELF(elf->data)) {
		warn("we no likey %s: {%s,%s,%s,%s}",
		     filename,
		     get_elfeitype(EI_CLASS, elf->data[EI_CLASS]),
		     get_elfeitype(EI_DATA, elf->data[EI_DATA]),
		     get_elfeitype(EI_VERSION, elf->data[EI_VERSION]),
		     get_elfeitype(EI_OSABI, elf->data[EI_OSABI]));
		goto free_elf_and_return;
	}

	elf->filename = filename;
	elf->base_filename = strrchr(filename, '/');
	if (elf->base_filename == NULL)
		elf->base_filename = elf->filename;
	else
		elf->base_filename = elf->base_filename + 1;
	elf->elf_class = elf->data[EI_CLASS];
	do_reverse_endian = (ELF_DATA != elf->data[EI_DATA]);

	/* for arches that need alignment, we have to make sure the buffer
	 * is strictly aligned.  archive (.a) files only align to 2 bytes
	 * while the arch can easily require 8.  so dupe the buffer so
	 * that our local copy is always aligned (since we can't shift the
	 * file mapping back and forth a few bytes).
	 */
	if (!__PAX_UNALIGNED_OK && ((unsigned long)elf->vdata & 0x7)) {
		elf->_data = xmalloc(elf->len);
		memcpy(elf->_data, elf->data, elf->len);
		elf->data = elf->_data;
		elf->data_end = elf->_data + elf->len;
	}

#define READELF_HEADER(B) \
	if (elf->elf_class == ELFCLASS ## B) { \
		char invalid; \
		Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
		Elf ## B ## _Off size; \
		/* verify program header */ \
		invalid = 0; \
		if (EGET(ehdr->e_phnum) <= 0) \
			invalid = 1; /* this is not abnormal so dont warn */ \
		else if (EGET(ehdr->e_phentsize) != sizeof(Elf ## B ## _Phdr)) \
			invalid = 3; \
		else { \
			elf->phdr = elf->vdata + EGET(ehdr->e_phoff); \
			size = EGET(ehdr->e_phnum) * EGET(ehdr->e_phentsize); \
			if (elf->phdr < elf->ehdr || /* check overflow */ \
			    elf->phdr + size < elf->phdr || /* before start of mem */ \
			    elf->phdr + size > elf->ehdr + elf->len) /* before end of mem */ \
				invalid = 2; \
		} \
		if (invalid > 1) \
			warn("%s: Invalid program header info (%i)", filename, invalid); \
		if (invalid) \
			elf->phdr = NULL; \
		/* verify section header */ \
		invalid = 0; \
		if (EGET(ehdr->e_shnum) <= 0) \
			invalid = 1; /* this is not abnormal so dont warn */ \
		else if (EGET(ehdr->e_shentsize) != sizeof(Elf ## B ## _Shdr)) \
			invalid = 3; \
		else { \
			elf->shdr = elf->vdata + EGET(ehdr->e_shoff); \
			size = EGET(ehdr->e_shnum) * EGET(ehdr->e_shentsize); \
			if (elf->shdr < elf->ehdr || /* check overflow */ \
			    elf->shdr + size < elf->shdr || /* before start of mem */ \
			    elf->shdr + size > elf->ehdr + elf->len) /* before end of mem */ \
				invalid = 2; \
		} \
		if (invalid > 1) \
			warn("%s: Invalid section header info (%i)", filename, invalid); \
		if (invalid) \
			elf->shdr = NULL; \
	}
	READELF_HEADER(32)
	READELF_HEADER(64)
	/* { char *p; strncpy(elf->basename, (p = strrchr(filename, '/')) == NULL ? "?" : p+1 , sizeof(elf->basename)); } */

	return elf;
}
elfobj *_readelf_fd(const char *filename, int fd, size_t len, int read_only)
{
	char *buffer;
	elfobj *ret;

	if (len == 0) {
		struct stat st;
		if (fstat(fd, &st) == -1)
			return NULL;
		len = st.st_size;
		if (len == 0)
			return NULL;
	}

	buffer = mmap(0, len, PROT_READ | (read_only ? 0 : PROT_WRITE), (read_only ? MAP_PRIVATE : MAP_SHARED), fd, 0);
	if (buffer == MAP_FAILED) {
		warn("mmap on '%s' of %li bytes failed :(", filename, (unsigned long)len);
		return NULL;
	}

	ret = readelf_buffer(filename, buffer, len);
	if (ret == NULL)
		munmap(buffer, len);
	else {
		ret->fd = fd;
		ret->is_mmap = 1;
	}

	return ret;
}
elfobj *_readelf(const char *filename, int read_only)
{
	elfobj *ret;
	struct stat st;
	int fd;

	if (stat(filename, &st) == -1)
		return NULL;

	if ((fd = open(filename, (read_only ? O_RDONLY : O_RDWR))) == -1)
		return NULL;

	/* make sure we have enough bytes to scan e_ident */
	if (st.st_size <= EI_NIDENT) {
close_fd_and_return:
		close(fd);
		return NULL;
	}

	ret = readelf_fd(filename, fd, st.st_size);
	if (ret == NULL)
		goto close_fd_and_return;

	return ret;
}

/* undo the readelf() stuff */
void unreadelf(elfobj *elf)
{
	if (elf->is_mmap) munmap(elf->vdata, elf->len);
	if (elf->fd != -1) close(elf->fd);
	if (!__PAX_UNALIGNED_OK) free(elf->_data);
	free(elf);
}

char *pax_short_hf_flags(unsigned long flags)
{
	static char buffer[7];

	buffer[0] = (flags & HF_PAX_PAGEEXEC ? 'p' : 'P');
	buffer[1] = (flags & HF_PAX_EMUTRAMP ? 'E' : 'e');
	buffer[2] = (flags & HF_PAX_MPROTECT ? 'm' : 'M');
	buffer[3] = (flags & HF_PAX_RANDMMAP ? 'r' : 'R');
	buffer[4] = (flags & HF_PAX_RANDEXEC ? 'X' : 'x');
	buffer[5] = (flags & HF_PAX_SEGMEXEC ? 's' : 'S');
	buffer[6] = 0;

	return buffer;
}

/* PT_PAX_FLAGS are tristate ...
 * the display logic is:
 * lower case: explicitly disabled
 * upper case: explicitly enabled
 *      -    : default */
char *pax_short_pf_flags(unsigned long flags)
{
	static char buffer[7];

#define PAX_STATE(pf_on, pf_off, disp_on, disp_off) \
	(flags & pf_on ? disp_on : (flags & pf_off ? disp_off : '-'))

	buffer[0] = PAX_STATE(PF_PAGEEXEC, PF_NOPAGEEXEC, 'P', 'p');
	buffer[1] = PAX_STATE(PF_SEGMEXEC, PF_NOSEGMEXEC, 'S', 's');
	buffer[2] = PAX_STATE(PF_MPROTECT, PF_NOMPROTECT, 'M', 'm');
	buffer[3] = PAX_STATE(PF_RANDEXEC, PF_NORANDEXEC, 'X', 'x');
	buffer[4] = PAX_STATE(PF_EMUTRAMP, PF_NOEMUTRAMP, 'E', 'e');
	buffer[5] = PAX_STATE(PF_RANDMMAP, PF_NORANDMMAP, 'R', 'r');
	buffer[6] = 0;

	if (((flags & PF_PAGEEXEC) && (flags & PF_NOPAGEEXEC)) || \
	    ((flags & PF_SEGMEXEC) && (flags & PF_NOSEGMEXEC)) || \
	    ((flags & PF_RANDMMAP) && (flags & PF_NORANDMMAP)) || \
	    ((flags & PF_RANDEXEC) && (flags & PF_NORANDEXEC)) || \
	    ((flags & PF_EMUTRAMP) && (flags & PF_NOEMUTRAMP)) || \
	    ((flags & PF_RANDMMAP) && (flags & PF_NORANDMMAP)))
		warn("inconsistent state detected.  flags=%lX\n", flags);

	return buffer;
}

char *gnu_short_stack_flags(unsigned long flags)
{
	static char buffer[4];

	buffer[0] = (flags & PF_R ? 'R' : '-');
	buffer[1] = (flags & PF_W ? 'W' : '-');
	buffer[2] = (flags & PF_X ? 'X' : '-');
	buffer[3] = 0;

	return buffer;
}

void *elf_findsecbyname(elfobj *elf, const char *name)
{
	unsigned int i;
	char *shdr_name;
	void *ret = NULL;

	if (elf->shdr == NULL) return NULL;

#define FINDSEC(B) \
	if (elf->elf_class == ELFCLASS ## B) { \
	Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
	Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \
	Elf ## B ## _Shdr *strtbl; \
	Elf ## B ## _Off offset; \
	uint16_t shstrndx = EGET(ehdr->e_shstrndx); \
	uint16_t shnum = EGET(ehdr->e_shnum); \
	if (shstrndx >= shnum) return NULL; \
	strtbl = &(shdr[shstrndx]); \
	for (i = 0; i < shnum; ++i) { \
		offset = EGET(strtbl->sh_offset) + EGET(shdr[i].sh_name); \
		if (offset >= (Elf ## B ## _Off)elf->len) continue; \
		shdr_name = elf->data + offset; \
		if (!strcmp(shdr_name, name)) { \
			if (ret) warnf("Multiple '%s' sections !?", name); \
			ret = (void*)&(shdr[i]); \
		} \
	} }
	FINDSEC(32)
	FINDSEC(64)

	return ret;
}