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Revision 1.245 - (show annotations) (download) (as text)
Sat Aug 4 06:08:25 2012 UTC (3 years ago) by vapier
Branch: MAIN
Changes since 1.244: +8 -3 lines
File MIME type: text/x-csrc
scanelf: add warnings when we cannot open an elf #427640 by Anthony Basile

1 /*
2 * Copyright 2003-2007 Gentoo Foundation
3 * Distributed under the terms of the GNU General Public License v2
4 * $Header: /var/cvsroot/gentoo-projects/pax-utils/scanelf.c,v 1.244 2012/04/29 06:21:36 vapier Exp $
5 *
6 * Copyright 2003-2007 Ned Ludd - <solar@gentoo.org>
7 * Copyright 2004-2007 Mike Frysinger - <vapier@gentoo.org>
8 */
9
10 static const char rcsid[] = "$Id: scanelf.c,v 1.244 2012/04/29 06:21:36 vapier Exp $";
11 const char argv0[] = "scanelf";
12
13 #include "paxinc.h"
14
15 #define IS_MODIFIER(c) (c == '%' || c == '#' || c == '+')
16
17 /* prototypes */
18 static int file_matches_list(const char *filename, char **matchlist);
19
20 /* variables to control behavior */
21 static char *match_etypes = NULL;
22 static array_t _ldpaths = array_init_decl, *ldpaths = &_ldpaths;
23 static char scan_ldpath = 0;
24 static char scan_envpath = 0;
25 static char scan_symlink = 1;
26 static char scan_archives = 0;
27 static char dir_recurse = 0;
28 static char dir_crossmount = 1;
29 static char show_pax = 0;
30 static char show_perms = 0;
31 static char show_size = 0;
32 static char show_phdr = 0;
33 static char show_textrel = 0;
34 static char show_rpath = 0;
35 static char show_needed = 0;
36 static char show_interp = 0;
37 static char show_bind = 0;
38 static char show_soname = 0;
39 static char show_textrels = 0;
40 static char show_banner = 1;
41 static char show_endian = 0;
42 static char show_osabi = 0;
43 static char show_eabi = 0;
44 static char be_quiet = 0;
45 static char be_verbose = 0;
46 static char be_wewy_wewy_quiet = 0;
47 static char be_semi_verbose = 0;
48 static char *find_sym = NULL;
49 static char *find_lib = NULL;
50 static array_t _find_lib_arr = array_init_decl, *find_lib_arr = &_find_lib_arr;
51 static char *find_section = NULL;
52 static array_t _find_section_arr = array_init_decl, *find_section_arr = &_find_section_arr;
53 static char *out_format = NULL;
54 static char *search_path = NULL;
55 static char fix_elf = 0;
56 static char g_match = 0;
57 static char use_ldcache = 0;
58 static char use_ldpath = 0;
59
60 static char **qa_textrels = NULL;
61 static char **qa_execstack = NULL;
62 static char **qa_wx_load = NULL;
63 static int root_fd = AT_FDCWD;
64
65 static int match_bits = 0;
66 static unsigned int match_perms = 0;
67 static void *ldcache = NULL;
68 static size_t ldcache_size = 0;
69 static unsigned long setpax = 0UL;
70
71 static int has_objdump = 0;
72
73 /* find the path to a file by name */
74 static int bin_in_path(const char *fname)
75 {
76 char fullpath[__PAX_UTILS_PATH_MAX];
77 char *path, *p;
78
79 path = getenv("PATH");
80 if (!path)
81 return 0;
82
83 while ((p = strrchr(path, ':')) != NULL) {
84 snprintf(fullpath, sizeof(fullpath), "%s/%s", p + 1, fname);
85 *p = 0;
86 if (access(fullpath, R_OK) != -1)
87 return 1;
88 }
89
90 return 0;
91 }
92
93 static FILE *fopenat_r(int dir_fd, const char *path)
94 {
95 int fd = openat(dir_fd, path, O_RDONLY|O_CLOEXEC);
96 if (fd == -1)
97 return NULL;
98 return fdopen(fd, "re");
99 }
100
101 static const char *root_rel_path(const char *path)
102 {
103 /*
104 * openat() will ignore the dirfd if path starts with
105 * a /, so consume all of that noise
106 *
107 * XXX: we don't handle relative paths like ../ that
108 * break out of the --root option, but for now, just
109 * don't do that :P.
110 */
111 if (root_fd != AT_FDCWD) {
112 while (*path == '/')
113 ++path;
114 if (*path == '\0')
115 path = ".";
116 }
117
118 return path;
119 }
120
121 /* 1 on failure. 0 otherwise */
122 static int rematch(const char *regex, const char *match, int cflags)
123 {
124 regex_t preg;
125 int ret;
126
127 if ((match == NULL) || (regex == NULL))
128 return EXIT_FAILURE;
129
130 if ((ret = regcomp(&preg, regex, cflags))) {
131 char err[256];
132
133 if (regerror(ret, &preg, err, sizeof(err)))
134 fprintf(stderr, "regcomp failed: %s", err);
135 else
136 fprintf(stderr, "regcomp failed");
137
138 return EXIT_FAILURE;
139 }
140 ret = regexec(&preg, match, 0, NULL, 0);
141 regfree(&preg);
142
143 return ret;
144 }
145
146 /* sub-funcs for scanelf_fileat() */
147 static void scanelf_file_get_symtabs(elfobj *elf, void **sym, void **str)
148 {
149 /* find the best SHT_DYNSYM and SHT_STRTAB sections */
150
151 /* debug sections */
152 void *symtab = elf_findsecbyname(elf, ".symtab");
153 void *strtab = elf_findsecbyname(elf, ".strtab");
154 /* runtime sections */
155 void *dynsym = elf_findsecbyname(elf, ".dynsym");
156 void *dynstr = elf_findsecbyname(elf, ".dynstr");
157
158 /*
159 * If the sections are marked NOBITS, then they don't exist, so we just
160 * skip them. This let's us work sanely with splitdebug ELFs (rather
161 * than spewing a lot of "corrupt ELF" messages later on). In malformed
162 * ELFs, the section might be wrongly set to NOBITS, but screw em.
163 */
164 #define GET_SYMTABS(B) \
165 if (elf->elf_class == ELFCLASS ## B) { \
166 Elf ## B ## _Shdr *esymtab = symtab; \
167 Elf ## B ## _Shdr *estrtab = strtab; \
168 Elf ## B ## _Shdr *edynsym = dynsym; \
169 Elf ## B ## _Shdr *edynstr = dynstr; \
170 \
171 if (symtab && EGET(esymtab->sh_type) == SHT_NOBITS) \
172 symtab = NULL; \
173 if (dynsym && EGET(edynsym->sh_type) == SHT_NOBITS) \
174 dynsym = NULL; \
175 if (symtab && dynsym) \
176 *sym = (EGET(esymtab->sh_size) > EGET(edynsym->sh_size)) ? symtab : dynsym; \
177 else \
178 *sym = symtab ? symtab : dynsym; \
179 \
180 if (strtab && EGET(estrtab->sh_type) == SHT_NOBITS) \
181 strtab = NULL; \
182 if (dynstr && EGET(edynstr->sh_type) == SHT_NOBITS) \
183 dynstr = NULL; \
184 if (strtab && dynstr) \
185 *str = (EGET(estrtab->sh_size) > EGET(edynstr->sh_size)) ? strtab : dynstr; \
186 else \
187 *str = strtab ? strtab : dynstr; \
188 }
189 GET_SYMTABS(32)
190 GET_SYMTABS(64)
191
192 if (*sym && *str)
193 return;
194
195 /*
196 * damn, they're really going to make us work for it huh?
197 * reconstruct the section header info out of the dynamic
198 * tags so we can see what symbols this guy uses at runtime.
199 */
200 #define GET_SYMTABS_DT(B) \
201 if (elf->elf_class == ELFCLASS ## B) { \
202 size_t i; \
203 static Elf ## B ## _Shdr sym_shdr, str_shdr; \
204 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
205 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
206 Elf ## B ## _Addr vsym, vstr, vhash, vgnu_hash; \
207 Elf ## B ## _Dyn *dyn; \
208 Elf ## B ## _Off offset; \
209 \
210 /* lookup symbols used at runtime with DT_SYMTAB / DT_STRTAB */ \
211 vsym = vstr = vhash = vgnu_hash = 0; \
212 memset(&sym_shdr, 0, sizeof(sym_shdr)); \
213 memset(&str_shdr, 0, sizeof(str_shdr)); \
214 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
215 if (EGET(phdr[i].p_type) != PT_DYNAMIC) \
216 continue; \
217 \
218 offset = EGET(phdr[i].p_offset); \
219 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) \
220 continue; \
221 \
222 dyn = DYN ## B (elf->vdata + offset); \
223 while (EGET(dyn->d_tag) != DT_NULL) { \
224 switch (EGET(dyn->d_tag)) { \
225 case DT_SYMTAB: vsym = EGET(dyn->d_un.d_val); break; \
226 case DT_SYMENT: sym_shdr.sh_entsize = dyn->d_un.d_val; break; \
227 case DT_STRTAB: vstr = EGET(dyn->d_un.d_val); break; \
228 case DT_STRSZ: str_shdr.sh_size = dyn->d_un.d_val; break; \
229 case DT_HASH: vhash = EGET(dyn->d_un.d_val); break; \
230 /*case DT_GNU_HASH: vgnu_hash = EGET(dyn->d_un.d_val); break;*/ \
231 } \
232 ++dyn; \
233 } \
234 if (vsym && vstr) \
235 break; \
236 } \
237 if (!vsym || !vstr || !(vhash || vgnu_hash)) \
238 return; \
239 \
240 /* calc offset into the ELF by finding the load addr of the syms */ \
241 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
242 Elf ## B ## _Addr vaddr = EGET(phdr[i].p_vaddr); \
243 Elf ## B ## _Addr filesz = EGET(phdr[i].p_filesz); \
244 offset = EGET(phdr[i].p_offset); \
245 \
246 if (EGET(phdr[i].p_type) != PT_LOAD) \
247 continue; \
248 \
249 if (vhash >= vaddr && vhash < vaddr + filesz) { \
250 /* Scan the hash table to see how many entries we have */ \
251 Elf32_Word max_sym_idx = 0; \
252 Elf32_Word *hashtbl = elf->vdata + offset + (vhash - vaddr); \
253 Elf32_Word b, nbuckets = EGET(hashtbl[0]); \
254 Elf32_Word nchains = EGET(hashtbl[1]); \
255 Elf32_Word *buckets = &hashtbl[2]; \
256 Elf32_Word *chains = &buckets[nbuckets]; \
257 Elf32_Word sym_idx; \
258 \
259 for (b = 0; b < nbuckets; ++b) { \
260 if (!buckets[b]) \
261 continue; \
262 for (sym_idx = buckets[b]; sym_idx < nchains && sym_idx; sym_idx = chains[sym_idx]) \
263 if (max_sym_idx < sym_idx) \
264 max_sym_idx = sym_idx; \
265 } \
266 ESET(sym_shdr.sh_size, sym_shdr.sh_entsize * max_sym_idx); \
267 } \
268 \
269 if (vsym >= vaddr && vsym < vaddr + filesz) { \
270 ESET(sym_shdr.sh_offset, offset + (vsym - vaddr)); \
271 *sym = &sym_shdr; \
272 } \
273 \
274 if (vstr >= vaddr && vstr < vaddr + filesz) { \
275 ESET(str_shdr.sh_offset, offset + (vstr - vaddr)); \
276 *str = &str_shdr; \
277 } \
278 } \
279 }
280 GET_SYMTABS_DT(32)
281 GET_SYMTABS_DT(64)
282 }
283
284 static char *scanelf_file_pax(elfobj *elf, char *found_pax)
285 {
286 static char ret[7];
287 unsigned long i, shown;
288
289 if (!show_pax) return NULL;
290
291 shown = 0;
292 memset(&ret, 0, sizeof(ret));
293
294 if (elf->phdr) {
295 #define SHOW_PAX(B) \
296 if (elf->elf_class == ELFCLASS ## B) { \
297 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
298 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
299 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
300 if (EGET(phdr[i].p_type) != PT_PAX_FLAGS) \
301 continue; \
302 if (fix_elf && setpax) { \
303 /* set the paxctl flags */ \
304 ESET(phdr[i].p_flags, setpax); \
305 } \
306 if (be_quiet && (EGET(phdr[i].p_flags) == (PF_NOEMUTRAMP | PF_NORANDEXEC))) \
307 continue; \
308 memcpy(ret, pax_short_pf_flags(EGET(phdr[i].p_flags)), 6); \
309 *found_pax = 1; \
310 ++shown; \
311 break; \
312 } \
313 }
314 SHOW_PAX(32)
315 SHOW_PAX(64)
316 }
317
318 /* Note: We do not support setting EI_PAX if not PT_PAX_FLAGS
319 * was found. This is known to break ELFs on glibc systems,
320 * and mainline PaX has deprecated use of this for a long time.
321 * We could support changing PT_GNU_STACK, but that doesn't
322 * seem like it's worth the effort. #411919
323 */
324
325 /* fall back to EI_PAX if no PT_PAX was found */
326 if (!*ret) {
327 static char *paxflags;
328 paxflags = pax_short_hf_flags(EI_PAX_FLAGS(elf));
329 if (!be_quiet || (be_quiet && EI_PAX_FLAGS(elf))) {
330 *found_pax = 1;
331 return (be_wewy_wewy_quiet ? NULL : paxflags);
332 }
333 strncpy(ret, paxflags, sizeof(ret));
334 }
335
336 if (be_wewy_wewy_quiet || (be_quiet && !shown))
337 return NULL;
338 else
339 return ret;
340 }
341
342 static char *scanelf_file_phdr(elfobj *elf, char *found_phdr, char *found_relro, char *found_load)
343 {
344 static char ret[12];
345 char *found;
346 unsigned long i, shown, multi_stack, multi_relro, multi_load;
347 int max_pt_load;
348
349 if (!show_phdr) return NULL;
350
351 memcpy(ret, "--- --- ---\0", 12);
352
353 shown = 0;
354 multi_stack = multi_relro = multi_load = 0;
355 max_pt_load = elf_max_pt_load(elf);
356
357 #define NOTE_GNU_STACK ".note.GNU-stack"
358 #define SHOW_PHDR(B) \
359 if (elf->elf_class == ELFCLASS ## B) { \
360 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
361 Elf ## B ## _Off offset; \
362 uint32_t flags, check_flags; \
363 if (elf->phdr != NULL) { \
364 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
365 for (i = 0; i < EGET(ehdr->e_phnum); ++i) { \
366 if (EGET(phdr[i].p_type) == PT_GNU_STACK) { \
367 if (multi_stack++) \
368 warnf("%s: multiple PT_GNU_STACK's !?", elf->filename); \
369 if (file_matches_list(elf->filename, qa_execstack)) \
370 continue; \
371 found = found_phdr; \
372 offset = 0; \
373 check_flags = PF_X; \
374 } else if (EGET(phdr[i].p_type) == PT_GNU_RELRO) { \
375 if (multi_relro++) \
376 warnf("%s: multiple PT_GNU_RELRO's !?", elf->filename); \
377 found = found_relro; \
378 offset = 4; \
379 check_flags = PF_X; \
380 } else if (EGET(phdr[i].p_type) == PT_LOAD) { \
381 if (EGET(ehdr->e_type) == ET_DYN || EGET(ehdr->e_type) == ET_EXEC) \
382 if (multi_load++ > max_pt_load) \
383 warnf("%s: more than %i PT_LOAD's !?", elf->filename, max_pt_load); \
384 if (file_matches_list(elf->filename, qa_wx_load)) \
385 continue; \
386 found = found_load; \
387 offset = 8; \
388 check_flags = PF_W|PF_X; \
389 } else \
390 continue; \
391 flags = EGET(phdr[i].p_flags); \
392 if (be_quiet && ((flags & check_flags) != check_flags)) \
393 continue; \
394 if ((EGET(phdr[i].p_type) != PT_LOAD) && (fix_elf && ((flags & PF_X) != flags))) { \
395 ESET(phdr[i].p_flags, flags & (PF_X ^ (size_t)-1)); \
396 ret[3] = ret[7] = '!'; \
397 flags = EGET(phdr[i].p_flags); \
398 } \
399 memcpy(ret+offset, gnu_short_stack_flags(flags), 3); \
400 *found = 1; \
401 ++shown; \
402 } \
403 } else if (elf->shdr != NULL) { \
404 /* no program headers which means this is prob an object file */ \
405 Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \
406 Elf ## B ## _Shdr *strtbl = shdr + EGET(ehdr->e_shstrndx); \
407 char *str; \
408 if ((void*)strtbl > elf->data_end) \
409 goto skip_this_shdr##B; \
410 check_flags = SHF_WRITE|SHF_EXECINSTR; \
411 for (i = 0; i < EGET(ehdr->e_shnum); ++i) { \
412 if (EGET(shdr[i].sh_type) != SHT_PROGBITS) continue; \
413 offset = EGET(strtbl->sh_offset) + EGET(shdr[i].sh_name); \
414 str = elf->data + offset; \
415 if (str > elf->data + offset + sizeof(NOTE_GNU_STACK)) continue; \
416 if (!strcmp(str, NOTE_GNU_STACK)) { \
417 if (multi_stack++) warnf("%s: multiple .note.GNU-stack's !?", elf->filename); \
418 flags = EGET(shdr[i].sh_flags); \
419 if (be_quiet && ((flags & check_flags) != check_flags)) \
420 continue; \
421 ++*found_phdr; \
422 shown = 1; \
423 if (flags & SHF_WRITE) ret[0] = 'W'; \
424 if (flags & SHF_ALLOC) ret[1] = 'A'; \
425 if (flags & SHF_EXECINSTR) ret[2] = 'X'; \
426 if (flags & 0xFFFFFFF8) warn("Invalid section flags for GNU-stack"); \
427 break; \
428 } \
429 } \
430 skip_this_shdr##B: \
431 if (!multi_stack) { \
432 if (file_matches_list(elf->filename, qa_execstack)) \
433 return NULL; \
434 *found_phdr = 1; \
435 shown = 1; \
436 memcpy(ret, "!WX", 3); \
437 } \
438 } \
439 }
440 SHOW_PHDR(32)
441 SHOW_PHDR(64)
442
443 if (be_wewy_wewy_quiet || (be_quiet && !shown))
444 return NULL;
445 else
446 return ret;
447 }
448
449 /*
450 * See if this ELF contains a DT_TEXTREL tag in any of its
451 * PT_DYNAMIC sections.
452 */
453 static const char *scanelf_file_textrel(elfobj *elf, char *found_textrel)
454 {
455 static const char *ret = "TEXTREL";
456 unsigned long i;
457
458 if (!show_textrel && !show_textrels) return NULL;
459
460 if (file_matches_list(elf->filename, qa_textrels)) return NULL;
461
462 if (elf->phdr) {
463 #define SHOW_TEXTREL(B) \
464 if (elf->elf_class == ELFCLASS ## B) { \
465 Elf ## B ## _Dyn *dyn; \
466 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
467 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
468 Elf ## B ## _Off offset; \
469 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
470 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) continue; \
471 offset = EGET(phdr[i].p_offset); \
472 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
473 dyn = DYN ## B (elf->vdata + offset); \
474 while (EGET(dyn->d_tag) != DT_NULL) { \
475 if (EGET(dyn->d_tag) == DT_TEXTREL) { /*dyn->d_tag != DT_FLAGS)*/ \
476 *found_textrel = 1; \
477 /*if (dyn->d_un.d_val & DF_TEXTREL)*/ \
478 return (be_wewy_wewy_quiet ? NULL : ret); \
479 } \
480 ++dyn; \
481 } \
482 } }
483 SHOW_TEXTREL(32)
484 SHOW_TEXTREL(64)
485 }
486
487 if (be_quiet || be_wewy_wewy_quiet)
488 return NULL;
489 else
490 return " - ";
491 }
492
493 /*
494 * Scan the .text section to see if there are any relocations in it.
495 * Should rewrite this to check PT_LOAD sections that are marked
496 * Executable rather than the section named '.text'.
497 */
498 static char *scanelf_file_textrels(elfobj *elf, char *found_textrels, char *found_textrel)
499 {
500 unsigned long s, r, rmax;
501 void *symtab_void, *strtab_void, *text_void;
502
503 if (!show_textrels) return NULL;
504
505 /* don't search for TEXTREL's if the ELF doesn't have any */
506 if (!*found_textrel) scanelf_file_textrel(elf, found_textrel);
507 if (!*found_textrel) return NULL;
508
509 scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
510 text_void = elf_findsecbyname(elf, ".text");
511
512 if (symtab_void && strtab_void && text_void && elf->shdr) {
513 #define SHOW_TEXTRELS(B) \
514 if (elf->elf_class == ELFCLASS ## B) { \
515 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
516 Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \
517 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
518 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
519 Elf ## B ## _Shdr *text = SHDR ## B (text_void); \
520 Elf ## B ## _Addr vaddr = EGET(text->sh_addr); \
521 uint ## B ## _t memsz = EGET(text->sh_size); \
522 Elf ## B ## _Rel *rel; \
523 Elf ## B ## _Rela *rela; \
524 /* search the section headers for relocations */ \
525 for (s = 0; s < EGET(ehdr->e_shnum); ++s) { \
526 uint32_t sh_type = EGET(shdr[s].sh_type); \
527 if (sh_type == SHT_REL) { \
528 rel = REL ## B (elf->vdata + EGET(shdr[s].sh_offset)); \
529 rela = NULL; \
530 rmax = EGET(shdr[s].sh_size) / sizeof(*rel); \
531 } else if (sh_type == SHT_RELA) { \
532 rel = NULL; \
533 rela = RELA ## B (elf->vdata + EGET(shdr[s].sh_offset)); \
534 rmax = EGET(shdr[s].sh_size) / sizeof(*rela); \
535 } else \
536 continue; \
537 /* now see if any of the relocs are in the .text */ \
538 for (r = 0; r < rmax; ++r) { \
539 unsigned long sym_max; \
540 Elf ## B ## _Addr offset_tmp; \
541 Elf ## B ## _Sym *func; \
542 Elf ## B ## _Sym *sym; \
543 Elf ## B ## _Addr r_offset; \
544 uint ## B ## _t r_info; \
545 if (sh_type == SHT_REL) { \
546 r_offset = EGET(rel[r].r_offset); \
547 r_info = EGET(rel[r].r_info); \
548 } else { \
549 r_offset = EGET(rela[r].r_offset); \
550 r_info = EGET(rela[r].r_info); \
551 } \
552 /* make sure this relocation is inside of the .text */ \
553 if (r_offset < vaddr || r_offset >= vaddr + memsz) { \
554 if (be_verbose <= 2) continue; \
555 } else \
556 *found_textrels = 1; \
557 /* locate this relocation symbol name */ \
558 sym = SYM ## B (elf->vdata + EGET(symtab->sh_offset)); \
559 if ((void*)sym > elf->data_end) { \
560 warn("%s: corrupt ELF symbol", elf->filename); \
561 continue; \
562 } \
563 sym_max = ELF ## B ## _R_SYM(r_info); \
564 if (sym_max * EGET(symtab->sh_entsize) < symtab->sh_size) \
565 sym += sym_max; \
566 else \
567 sym = NULL; \
568 sym_max = EGET(symtab->sh_size) / EGET(symtab->sh_entsize); \
569 /* show the raw details about this reloc */ \
570 printf(" %s: ", elf->base_filename); \
571 if (sym && sym->st_name) \
572 printf("%s", elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name)); \
573 else \
574 printf("(memory/data?)"); \
575 printf(" [0x%lX]", (unsigned long)r_offset); \
576 /* now try to find the closest symbol that this rel is probably in */ \
577 sym = SYM ## B (elf->vdata + EGET(symtab->sh_offset)); \
578 func = NULL; \
579 offset_tmp = 0; \
580 while (sym_max--) { \
581 if (EGET(sym->st_value) < r_offset && EGET(sym->st_value) > offset_tmp) { \
582 func = sym; \
583 offset_tmp = EGET(sym->st_value); \
584 } \
585 ++sym; \
586 } \
587 printf(" in "); \
588 if (func && func->st_name) { \
589 const char *func_name = elf->data + EGET(strtab->sh_offset) + EGET(func->st_name); \
590 if (r_offset > EGET(func->st_size)) \
591 printf("(optimized out: previous %s)", func_name); \
592 else \
593 printf("%s", func_name); \
594 } else \
595 printf("(optimized out)"); \
596 printf(" [0x%lX]\n", (unsigned long)offset_tmp); \
597 if (be_verbose && has_objdump) { \
598 Elf ## B ## _Addr end_addr = offset_tmp + EGET(func->st_size); \
599 char *sysbuf; \
600 size_t syslen; \
601 const char sysfmt[] = "objdump -r -R -d -w -l --start-address=0x%lX --stop-address=0x%lX %s | grep --color -i -C 3 '.*[[:space:]]%lX:[[:space:]]*R_.*'\n"; \
602 syslen = sizeof(sysfmt) + strlen(elf->filename) + 3 * sizeof(unsigned long) + 1; \
603 sysbuf = xmalloc(syslen); \
604 if (end_addr < r_offset) \
605 /* not uncommon when things are optimized out */ \
606 end_addr = r_offset + 0x100; \
607 snprintf(sysbuf, syslen, sysfmt, \
608 (unsigned long)offset_tmp, \
609 (unsigned long)end_addr, \
610 elf->filename, \
611 (unsigned long)r_offset); \
612 fflush(stdout); \
613 if (system(sysbuf)) /* don't care */; \
614 fflush(stdout); \
615 free(sysbuf); \
616 } \
617 } \
618 } }
619 SHOW_TEXTRELS(32)
620 SHOW_TEXTRELS(64)
621 }
622 if (!*found_textrels)
623 warnf("ELF %s has TEXTREL markings but doesnt appear to have any real TEXTREL's !?", elf->filename);
624
625 return NULL;
626 }
627
628 static void rpath_security_checks(elfobj *elf, char *item, const char *dt_type)
629 {
630 struct stat st;
631 switch (*item) {
632 case '/': break;
633 case '.':
634 warnf("Security problem with relative %s '%s' in %s", dt_type, item, elf->filename);
635 break;
636 case ':':
637 case '\0':
638 warnf("Security problem NULL %s in %s", dt_type, elf->filename);
639 break;
640 case '$':
641 if (fstat(elf->fd, &st) != -1)
642 if ((st.st_mode & S_ISUID) || (st.st_mode & S_ISGID))
643 warnf("Security problem with %s='%s' in %s with mode set of %o",
644 dt_type, item, elf->filename, (unsigned int) st.st_mode & 07777);
645 break;
646 default:
647 warnf("Maybe? sec problem with %s='%s' in %s", dt_type, item, elf->filename);
648 break;
649 }
650 }
651 static void scanelf_file_rpath(elfobj *elf, char *found_rpath, char **ret, size_t *ret_len)
652 {
653 unsigned long i;
654 char *rpath, *runpath, **r;
655 void *strtbl_void;
656
657 if (!show_rpath) return;
658
659 strtbl_void = elf_findsecbyname(elf, ".dynstr");
660 rpath = runpath = NULL;
661
662 if (elf->phdr && strtbl_void) {
663 #define SHOW_RPATH(B) \
664 if (elf->elf_class == ELFCLASS ## B) { \
665 Elf ## B ## _Dyn *dyn; \
666 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
667 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
668 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
669 Elf ## B ## _Off offset; \
670 Elf ## B ## _Xword word; \
671 /* Scan all the program headers */ \
672 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
673 /* Just scan dynamic headers */ \
674 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) continue; \
675 offset = EGET(phdr[i].p_offset); \
676 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
677 /* Just scan dynamic RPATH/RUNPATH headers */ \
678 dyn = DYN ## B (elf->vdata + offset); \
679 while ((word=EGET(dyn->d_tag)) != DT_NULL) { \
680 if (word == DT_RPATH) { \
681 r = &rpath; \
682 } else if (word == DT_RUNPATH) { \
683 r = &runpath; \
684 } else { \
685 ++dyn; \
686 continue; \
687 } \
688 /* Verify the memory is somewhat sane */ \
689 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
690 if (offset < (Elf ## B ## _Off)elf->len) { \
691 if (*r) warn("ELF has multiple %s's !?", get_elfdtype(word)); \
692 *r = elf->data + offset; \
693 /* cache the length in case we need to nuke this section later on */ \
694 if (fix_elf) \
695 offset = strlen(*r); \
696 /* If quiet, don't output paths in ld.so.conf */ \
697 if (be_quiet) { \
698 size_t len; \
699 char *start, *end; \
700 /* note that we only 'chop' off leading known paths. */ \
701 /* since *r is read-only memory, we can only move the ptr forward. */ \
702 start = *r; \
703 /* scan each path in : delimited list */ \
704 while (start) { \
705 rpath_security_checks(elf, start, get_elfdtype(word)); \
706 end = strchr(start, ':'); \
707 len = (end ? abs(end - start) : strlen(start)); \
708 if (use_ldcache) { \
709 size_t n; \
710 const char *ldpath; \
711 array_for_each(ldpaths, n, ldpath) \
712 if (!strncmp(ldpath, start, len) && !ldpath[len]) { \
713 *r = end; \
714 /* corner case ... if RPATH reads "/usr/lib:", we want \
715 * to show ':' rather than '' */ \
716 if (end && end[1] != '\0') \
717 (*r)++; \
718 break; \
719 } \
720 } \
721 if (!*r || !end) \
722 break; \
723 else \
724 start = start + len + 1; \
725 } \
726 } \
727 if (*r) { \
728 if (fix_elf > 2 || (fix_elf && **r == '\0')) { \
729 /* just nuke it */ \
730 nuke_it##B: \
731 memset(*r, 0x00, offset); \
732 *r = NULL; \
733 ESET(dyn->d_tag, DT_DEBUG); \
734 ESET(dyn->d_un.d_ptr, 0); \
735 } else if (fix_elf) { \
736 /* try to clean "bad" paths */ \
737 size_t len, tmpdir_len; \
738 char *start, *end; \
739 const char *tmpdir; \
740 start = *r; \
741 tmpdir = (getenv("TMPDIR") ? : "."); \
742 tmpdir_len = strlen(tmpdir); \
743 while (1) { \
744 end = strchr(start, ':'); \
745 if (start == end) { \
746 eat_this_path##B: \
747 len = strlen(end); \
748 memmove(start, end+1, len); \
749 start[len-1] = '\0'; \
750 end = start - 1; \
751 } else if (tmpdir && !strncmp(start, tmpdir, tmpdir_len)) { \
752 if (!end) { \
753 if (start == *r) \
754 goto nuke_it##B; \
755 *--start = '\0'; \
756 } else \
757 goto eat_this_path##B; \
758 } \
759 if (!end) \
760 break; \
761 start = end + 1; \
762 } \
763 if (**r == '\0') \
764 goto nuke_it##B; \
765 } \
766 if (*r) \
767 *found_rpath = 1; \
768 } \
769 } \
770 ++dyn; \
771 } \
772 } }
773 SHOW_RPATH(32)
774 SHOW_RPATH(64)
775 }
776
777 if (be_wewy_wewy_quiet) return;
778
779 if (rpath && runpath) {
780 if (!strcmp(rpath, runpath)) {
781 xstrcat(ret, runpath, ret_len);
782 } else {
783 fprintf(stderr, "RPATH [%s] != RUNPATH [%s]\n", rpath, runpath);
784 xchrcat(ret, '{', ret_len);
785 xstrcat(ret, rpath, ret_len);
786 xchrcat(ret, ',', ret_len);
787 xstrcat(ret, runpath, ret_len);
788 xchrcat(ret, '}', ret_len);
789 }
790 } else if (rpath || runpath)
791 xstrcat(ret, (runpath ? runpath : rpath), ret_len);
792 else if (!be_quiet)
793 xstrcat(ret, " - ", ret_len);
794 }
795
796 #define LDSO_CACHE_MAGIC "ld.so-"
797 #define LDSO_CACHE_MAGIC_LEN (sizeof LDSO_CACHE_MAGIC -1)
798 #define LDSO_CACHE_VER "1.7.0"
799 #define LDSO_CACHE_VER_LEN (sizeof LDSO_CACHE_VER -1)
800 #define FLAG_ANY -1
801 #define FLAG_TYPE_MASK 0x00ff
802 #define FLAG_LIBC4 0x0000
803 #define FLAG_ELF 0x0001
804 #define FLAG_ELF_LIBC5 0x0002
805 #define FLAG_ELF_LIBC6 0x0003
806 #define FLAG_REQUIRED_MASK 0xff00
807 #define FLAG_SPARC_LIB64 0x0100
808 #define FLAG_IA64_LIB64 0x0200
809 #define FLAG_X8664_LIB64 0x0300
810 #define FLAG_S390_LIB64 0x0400
811 #define FLAG_POWERPC_LIB64 0x0500
812 #define FLAG_MIPS64_LIBN32 0x0600
813 #define FLAG_MIPS64_LIBN64 0x0700
814
815 #if defined(__GLIBC__) || defined(__UCLIBC__)
816
817 static char *lookup_cache_lib(elfobj *elf, const char *fname)
818 {
819 int fd;
820 char *strs;
821 static char buf[__PAX_UTILS_PATH_MAX] = "";
822 const char *cachefile = root_rel_path("/etc/ld.so.cache");
823 struct stat st;
824
825 typedef struct {
826 char magic[LDSO_CACHE_MAGIC_LEN];
827 char version[LDSO_CACHE_VER_LEN];
828 int nlibs;
829 } header_t;
830 header_t *header;
831
832 typedef struct {
833 int flags;
834 int sooffset;
835 int liboffset;
836 } libentry_t;
837 libentry_t *libent;
838
839 if (fname == NULL)
840 return NULL;
841
842 if (ldcache == NULL) {
843 if (fstatat(root_fd, cachefile, &st, 0))
844 return NULL;
845
846 fd = openat(root_fd, cachefile, O_RDONLY);
847 if (fd == -1)
848 return NULL;
849
850 /* cache these values so we only map/unmap the cache file once */
851 ldcache_size = st.st_size;
852 header = ldcache = mmap(0, ldcache_size, PROT_READ, MAP_SHARED, fd, 0);
853 close(fd);
854
855 if (ldcache == MAP_FAILED) {
856 ldcache = NULL;
857 return NULL;
858 }
859
860 if (memcmp(header->magic, LDSO_CACHE_MAGIC, LDSO_CACHE_MAGIC_LEN) ||
861 memcmp(header->version, LDSO_CACHE_VER, LDSO_CACHE_VER_LEN))
862 {
863 munmap(ldcache, ldcache_size);
864 ldcache = NULL;
865 return NULL;
866 }
867 } else
868 header = ldcache;
869
870 libent = ldcache + sizeof(header_t);
871 strs = (char *) &libent[header->nlibs];
872
873 for (fd = 0; fd < header->nlibs; ++fd) {
874 /* This should be more fine grained, but for now we assume that
875 * diff arches will not be cached together, and we ignore the
876 * the different multilib mips cases.
877 */
878 if (elf->elf_class == ELFCLASS64 && !(libent[fd].flags & FLAG_REQUIRED_MASK))
879 continue;
880 if (elf->elf_class == ELFCLASS32 && (libent[fd].flags & FLAG_REQUIRED_MASK))
881 continue;
882
883 if (strcmp(fname, strs + libent[fd].sooffset) != 0)
884 continue;
885
886 /* Return first hit because that is how the ldso rolls */
887 strncpy(buf, strs + libent[fd].liboffset, sizeof(buf));
888 break;
889 }
890
891 return buf;
892 }
893
894 #elif defined(__NetBSD__)
895 static char *lookup_cache_lib(elfobj *elf, const char *fname)
896 {
897 static char buf[__PAX_UTILS_PATH_MAX] = "";
898 static struct stat st;
899 size_t n;
900 char *ldpath;
901
902 array_for_each(ldpath, n, ldpath) {
903 if ((unsigned) snprintf(buf, sizeof(buf), "%s/%s", ldpath, fname) >= sizeof(buf))
904 continue; /* if the pathname is too long, or something went wrong, ignore */
905
906 if (stat(buf, &st) != 0)
907 continue; /* if the lib doesn't exist in *ldpath, look further */
908
909 /* NetBSD doesn't actually do sanity checks, it just loads the file
910 * and if that doesn't work, continues looking in other directories.
911 * This cannot easily be safely emulated, unfortunately. For now,
912 * just assume that if it exists, it's a valid library. */
913
914 return buf;
915 }
916
917 /* not found in any path */
918 return NULL;
919 }
920 #else
921 #ifdef __ELF__
922 #warning Cache support not implemented for your target
923 #endif
924 static char *lookup_cache_lib(elfobj *elf, const char *fname)
925 {
926 return NULL;
927 }
928 #endif
929
930 static char *lookup_config_lib(elfobj *elf, char *fname)
931 {
932 static char buf[__PAX_UTILS_PATH_MAX] = "";
933 const char *ldpath;
934 size_t n;
935
936 array_for_each(ldpaths, n, ldpath) {
937 snprintf(buf, sizeof(buf), "%s/%s", root_rel_path(ldpath), fname);
938 if (faccessat(root_fd, buf, F_OK, AT_SYMLINK_NOFOLLOW) == 0)
939 return buf;
940 }
941
942 return NULL;
943 }
944
945 static const char *scanelf_file_needed_lib(elfobj *elf, char *found_needed, char *found_lib, int op, char **ret, size_t *ret_len)
946 {
947 unsigned long i;
948 char *needed;
949 void *strtbl_void;
950 char *p;
951
952 /*
953 * -n -> op==0 -> print all
954 * -N -> op==1 -> print requested
955 */
956 if ((op == 0 && !show_needed) || (op == 1 && !find_lib))
957 return NULL;
958
959 strtbl_void = elf_findsecbyname(elf, ".dynstr");
960
961 if (elf->phdr && strtbl_void) {
962 #define SHOW_NEEDED(B) \
963 if (elf->elf_class == ELFCLASS ## B) { \
964 Elf ## B ## _Dyn *dyn; \
965 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
966 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
967 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
968 Elf ## B ## _Off offset; \
969 size_t matched = 0; \
970 /* Walk all the program headers to find the PT_DYNAMIC */ \
971 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
972 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) \
973 continue; \
974 offset = EGET(phdr[i].p_offset); \
975 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) \
976 continue; \
977 /* Walk all the dynamic tags to find NEEDED entries */ \
978 dyn = DYN ## B (elf->vdata + offset); \
979 while (EGET(dyn->d_tag) != DT_NULL) { \
980 if (EGET(dyn->d_tag) == DT_NEEDED) { \
981 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
982 if (offset >= (Elf ## B ## _Off)elf->len) { \
983 ++dyn; \
984 continue; \
985 } \
986 needed = elf->data + offset; \
987 if (op == 0) { \
988 /* -n -> print all entries */ \
989 if (!be_wewy_wewy_quiet) { \
990 if (*found_needed) xchrcat(ret, ',', ret_len); \
991 if (use_ldpath) { \
992 if ((p = lookup_config_lib(elf, needed)) != NULL) \
993 needed = p; \
994 } else if (use_ldcache) { \
995 if ((p = lookup_cache_lib(elf, needed)) != NULL) \
996 needed = p; \
997 } \
998 xstrcat(ret, needed, ret_len); \
999 } \
1000 *found_needed = 1; \
1001 } else { \
1002 /* -N -> print matching entries */ \
1003 size_t n; \
1004 const char *find_lib_name; \
1005 \
1006 array_for_each(find_lib_arr, n, find_lib_name) { \
1007 int invert = 1; \
1008 if (find_lib_name[0] == '!') \
1009 invert = 0, ++find_lib_name; \
1010 if (!strcmp(find_lib_name, needed) == invert) \
1011 ++matched; \
1012 } \
1013 \
1014 if (matched == array_cnt(find_lib_arr)) { \
1015 *found_lib = 1; \
1016 return (be_wewy_wewy_quiet ? NULL : find_lib); \
1017 } \
1018 } \
1019 } \
1020 ++dyn; \
1021 } \
1022 } }
1023 SHOW_NEEDED(32)
1024 SHOW_NEEDED(64)
1025 if (op == 0 && !*found_needed && be_verbose)
1026 warn("ELF lacks DT_NEEDED sections: %s", elf->filename);
1027 }
1028
1029 return NULL;
1030 }
1031 static char *scanelf_file_interp(elfobj *elf, char *found_interp)
1032 {
1033 void *strtbl_void;
1034
1035 if (!show_interp) return NULL;
1036
1037 strtbl_void = elf_findsecbyname(elf, ".interp");
1038
1039 if (strtbl_void) {
1040 #define SHOW_INTERP(B) \
1041 if (elf->elf_class == ELFCLASS ## B) { \
1042 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
1043 *found_interp = 1; \
1044 return (be_wewy_wewy_quiet ? NULL : elf->data + EGET(strtbl->sh_offset)); \
1045 }
1046 SHOW_INTERP(32)
1047 SHOW_INTERP(64)
1048 }
1049 return NULL;
1050 }
1051 static char *scanelf_file_bind(elfobj *elf, char *found_bind)
1052 {
1053 unsigned long i;
1054 struct stat s;
1055 char dynamic = 0;
1056
1057 if (!show_bind) return NULL;
1058 if (!elf->phdr) return NULL;
1059
1060 #define SHOW_BIND(B) \
1061 if (elf->elf_class == ELFCLASS ## B) { \
1062 Elf ## B ## _Dyn *dyn; \
1063 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
1064 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
1065 Elf ## B ## _Off offset; \
1066 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
1067 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) continue; \
1068 dynamic = 1; \
1069 offset = EGET(phdr[i].p_offset); \
1070 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
1071 dyn = DYN ## B (elf->vdata + offset); \
1072 while (EGET(dyn->d_tag) != DT_NULL) { \
1073 if (EGET(dyn->d_tag) == DT_BIND_NOW || \
1074 (EGET(dyn->d_tag) == DT_FLAGS && EGET(dyn->d_un.d_val) & DF_BIND_NOW)) \
1075 { \
1076 if (be_quiet) return NULL; \
1077 *found_bind = 1; \
1078 return (char *)(be_wewy_wewy_quiet ? NULL : "NOW"); \
1079 } \
1080 ++dyn; \
1081 } \
1082 } \
1083 }
1084 SHOW_BIND(32)
1085 SHOW_BIND(64)
1086
1087 if (be_wewy_wewy_quiet) return NULL;
1088
1089 /* don't output anything if quiet mode and the ELF is static or not setuid */
1090 if (be_quiet && (!dynamic || (!fstat(elf->fd, &s) && !(s.st_mode & (S_ISUID|S_ISGID))))) {
1091 return NULL;
1092 } else {
1093 *found_bind = 1;
1094 return (char *)(dynamic ? "LAZY" : "STATIC");
1095 }
1096 }
1097 static char *scanelf_file_soname(elfobj *elf, char *found_soname)
1098 {
1099 unsigned long i;
1100 char *soname;
1101 void *strtbl_void;
1102
1103 if (!show_soname) return NULL;
1104
1105 strtbl_void = elf_findsecbyname(elf, ".dynstr");
1106
1107 if (elf->phdr && strtbl_void) {
1108 #define SHOW_SONAME(B) \
1109 if (elf->elf_class == ELFCLASS ## B) { \
1110 Elf ## B ## _Dyn *dyn; \
1111 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
1112 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
1113 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
1114 Elf ## B ## _Off offset; \
1115 /* only look for soname in shared objects */ \
1116 if (EGET(ehdr->e_type) != ET_DYN) \
1117 return NULL; \
1118 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
1119 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) continue; \
1120 offset = EGET(phdr[i].p_offset); \
1121 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
1122 dyn = DYN ## B (elf->vdata + offset); \
1123 while (EGET(dyn->d_tag) != DT_NULL) { \
1124 if (EGET(dyn->d_tag) == DT_SONAME) { \
1125 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
1126 if (offset >= (Elf ## B ## _Off)elf->len) { \
1127 ++dyn; \
1128 continue; \
1129 } \
1130 soname = elf->data + offset; \
1131 *found_soname = 1; \
1132 return (be_wewy_wewy_quiet ? NULL : soname); \
1133 } \
1134 ++dyn; \
1135 } \
1136 } }
1137 SHOW_SONAME(32)
1138 SHOW_SONAME(64)
1139 }
1140
1141 return NULL;
1142 }
1143
1144 /*
1145 * We support the symbol form:
1146 * [%[modifiers]%][[+-]<symbol name>][,[.....]]
1147 * If the symbol name is empty, then all symbols are matched.
1148 * If the symbol name is a glob ("*"), then all symbols are dumped (debug).
1149 * Do not rely on this output format at all.
1150 * Otherwise the symbol name is used to search (either regex or string compare).
1151 * If the first char of the symbol name is a plus ("+"), then only match
1152 * defined symbols. If it's a minus ("-"), only match undefined symbols.
1153 * Putting modifiers in between the percent signs allows for more in depth
1154 * filters. There are groups of modifiers. If you don't specify a member
1155 * of a group, then all types in that group are matched. The current
1156 * groups and their types are:
1157 * STT group: STT_NOTYPE:n STT_OBJECT:o STT_FUNC:f STT_FILE:F
1158 * STB group: STB_LOCAL:l STB_GLOBAL:g STB_WEAK:w
1159 * SHN group: SHN_UNDEF:u SHN_ABS:a SHN_COMMON:c {defined}:d
1160 * The "defined" value in the SHN group does not correspond to a SHN_xxx define.
1161 * You can search for multiple symbols at once by seperating with a comma (",").
1162 *
1163 * Some examples:
1164 * ELFs with a weak function "foo":
1165 * scanelf -s %wf%foo <ELFs>
1166 * ELFs that define the symbol "main":
1167 * scanelf -s +main <ELFs>
1168 * scanelf -s %d%main <ELFs>
1169 * ELFs that refer to the undefined symbol "brk":
1170 * scanelf -s -brk <ELFs>
1171 * scanelf -s %u%brk <ELFs>
1172 * All global defined objects in an ELF:
1173 * scanelf -s %ogd% <ELF>
1174 */
1175 static void
1176 scanelf_match_symname(elfobj *elf, char *found_sym, char **ret, size_t *ret_len, const char *symname,
1177 unsigned int stt, unsigned int stb, unsigned int shn, unsigned long size)
1178 {
1179 char *this_sym, *next_sym, saved = saved;
1180
1181 /* allow the user to specify a comma delimited list of symbols to search for */
1182 next_sym = NULL;
1183 do {
1184 bool inc_notype, inc_object, inc_func, inc_file,
1185 inc_local, inc_global, inc_weak,
1186 inc_def, inc_undef, inc_abs, inc_common;
1187
1188 if (next_sym) {
1189 next_sym[-1] = saved;
1190 this_sym = next_sym;
1191 } else
1192 this_sym = find_sym;
1193 if ((next_sym = strchr(this_sym, ','))) {
1194 /* make parsing easier by killing the comma temporarily */
1195 saved = *next_sym;
1196 *next_sym = '\0';
1197 next_sym += 1;
1198 }
1199
1200 /* symbol selection! */
1201 inc_notype = inc_object = inc_func = inc_file = \
1202 inc_local = inc_global = inc_weak = \
1203 inc_def = inc_undef = inc_abs = inc_common = \
1204 (*this_sym != '%');
1205
1206 /* parse the contents of %...% */
1207 if (!inc_notype) {
1208 while (*(this_sym++)) {
1209 if (*this_sym == '%') {
1210 ++this_sym;
1211 break;
1212 }
1213 switch (*this_sym) {
1214 case 'n': inc_notype = true; break;
1215 case 'o': inc_object = true; break;
1216 case 'f': inc_func = true; break;
1217 case 'F': inc_file = true; break;
1218 case 'l': inc_local = true; break;
1219 case 'g': inc_global = true; break;
1220 case 'w': inc_weak = true; break;
1221 case 'd': inc_def = true; break;
1222 case 'u': inc_undef = true; break;
1223 case 'a': inc_abs = true; break;
1224 case 'c': inc_common = true; break;
1225 default: err("invalid symbol selector '%c'", *this_sym);
1226 }
1227 }
1228
1229 /* If no types are matched, not match all */
1230 if (!inc_notype && !inc_object && !inc_func && !inc_file)
1231 inc_notype = inc_object = inc_func = inc_file = true;
1232 if (!inc_local && !inc_global && !inc_weak)
1233 inc_local = inc_global = inc_weak = true;
1234 if (!inc_def && !inc_undef && !inc_abs && !inc_common)
1235 inc_def = inc_undef = inc_abs = inc_common = true;
1236
1237 /* backwards compat for defined/undefined short hand */
1238 } else if (*this_sym == '+') {
1239 inc_undef = false;
1240 ++this_sym;
1241 } else if (*this_sym == '-') {
1242 inc_def = inc_abs = inc_common = false;
1243 ++this_sym;
1244 }
1245
1246 /* filter symbols */
1247 if ((!inc_notype && stt == STT_NOTYPE) || \
1248 (!inc_object && stt == STT_OBJECT) || \
1249 (!inc_func && stt == STT_FUNC ) || \
1250 (!inc_file && stt == STT_FILE ) || \
1251 (!inc_local && stb == STB_LOCAL ) || \
1252 (!inc_global && stb == STB_GLOBAL) || \
1253 (!inc_weak && stb == STB_WEAK ) || \
1254 (!inc_def && shn && shn < SHN_LORESERVE) || \
1255 (!inc_undef && shn == SHN_UNDEF ) || \
1256 (!inc_abs && shn == SHN_ABS ) || \
1257 (!inc_common && shn == SHN_COMMON))
1258 continue;
1259
1260 if (*this_sym == '*') {
1261 /* a "*" symbol gets you debug output */
1262 printf("%s(%s) %5lX %15s %15s %15s %s\n",
1263 ((*found_sym == 0) ? "\n\t" : "\t"),
1264 elf->base_filename,
1265 size,
1266 get_elfstttype(stt),
1267 get_elfstbtype(stb),
1268 get_elfshntype(shn),
1269 symname);
1270 goto matched;
1271
1272 } else {
1273 if (g_match) {
1274 /* regex match the symbol */
1275 if (rematch(this_sym, symname, REG_EXTENDED) != 0)
1276 continue;
1277
1278 } else if (*this_sym) {
1279 /* give empty symbols a "pass", else do a normal compare */
1280 const size_t len = strlen(this_sym);
1281 if (!(strncmp(this_sym, symname, len) == 0 &&
1282 /* Accept unversioned symbol names */
1283 (symname[len] == '\0' || symname[len] == '@')))
1284 continue;
1285 }
1286
1287 if (be_semi_verbose) {
1288 char buf[1024];
1289 snprintf(buf, sizeof(buf), "%lX %s %s",
1290 size,
1291 get_elfstttype(stt),
1292 this_sym);
1293 *ret = xstrdup(buf);
1294 } else {
1295 if (*ret) xchrcat(ret, ',', ret_len);
1296 xstrcat(ret, symname, ret_len);
1297 }
1298
1299 goto matched;
1300 }
1301 } while (next_sym);
1302
1303 return;
1304
1305 matched:
1306 *found_sym = 1;
1307 if (next_sym)
1308 next_sym[-1] = saved;
1309 }
1310
1311 static const char *scanelf_file_sym(elfobj *elf, char *found_sym)
1312 {
1313 char *ret;
1314 void *symtab_void, *strtab_void;
1315
1316 if (!find_sym) return NULL;
1317 ret = NULL;
1318
1319 scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
1320
1321 if (symtab_void && strtab_void) {
1322 #define FIND_SYM(B) \
1323 if (elf->elf_class == ELFCLASS ## B) { \
1324 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
1325 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
1326 Elf ## B ## _Sym *sym = SYM ## B (elf->vdata + EGET(symtab->sh_offset)); \
1327 Elf ## B ## _Word i, cnt = EGET(symtab->sh_entsize); \
1328 char *symname; \
1329 size_t ret_len = 0; \
1330 if (cnt) \
1331 cnt = EGET(symtab->sh_size) / cnt; \
1332 for (i = 0; i < cnt; ++i) { \
1333 if ((void*)sym > elf->data_end) { \
1334 warnf("%s: corrupt ELF symbols - aborting", elf->filename); \
1335 goto break_out; \
1336 } \
1337 if (sym->st_name) { \
1338 /* make sure the symbol name is in acceptable memory range */ \
1339 symname = elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name); \
1340 if ((void*)symname > elf->data_end) { \
1341 warnf("%s: corrupt ELF symbols", elf->filename); \
1342 ++sym; \
1343 continue; \
1344 } \
1345 scanelf_match_symname(elf, found_sym, \
1346 &ret, &ret_len, symname, \
1347 ELF##B##_ST_TYPE(EGET(sym->st_info)), \
1348 ELF##B##_ST_BIND(EGET(sym->st_info)), \
1349 EGET(sym->st_shndx), \
1350 /* st_size can be 64bit, but no one is really that big, so screw em */ \
1351 EGET(sym->st_size)); \
1352 } \
1353 ++sym; \
1354 } \
1355 }
1356 FIND_SYM(32)
1357 FIND_SYM(64)
1358 }
1359
1360 break_out:
1361 if (be_wewy_wewy_quiet) return NULL;
1362
1363 if (*find_sym != '*' && *found_sym)
1364 return ret;
1365 if (be_quiet)
1366 return NULL;
1367 else
1368 return " - ";
1369 }
1370
1371 static const char *scanelf_file_sections(elfobj *elf, char *found_section)
1372 {
1373 if (!find_section)
1374 return NULL;
1375
1376 #define FIND_SECTION(B) \
1377 if (elf->elf_class == ELFCLASS ## B) { \
1378 size_t matched, n; \
1379 int invert; \
1380 const char *section_name; \
1381 Elf ## B ## _Shdr *section; \
1382 \
1383 matched = 0; \
1384 array_for_each(find_section_arr, n, section_name) { \
1385 invert = (*section_name == '!' ? 1 : 0); \
1386 section = SHDR ## B (elf_findsecbyname(elf, section_name + invert)); \
1387 if ((section == NULL && invert) || (section != NULL && !invert)) \
1388 ++matched; \
1389 } \
1390 \
1391 if (matched == array_cnt(find_section_arr)) \
1392 *found_section = 1; \
1393 }
1394 FIND_SECTION(32)
1395 FIND_SECTION(64)
1396
1397 if (be_wewy_wewy_quiet)
1398 return NULL;
1399
1400 if (*found_section)
1401 return find_section;
1402
1403 if (be_quiet)
1404 return NULL;
1405 else
1406 return " - ";
1407 }
1408
1409 /* scan an elf file and show all the fun stuff */
1410 #define prints(str) ({ ssize_t ret = write(fileno(stdout), str, strlen(str)); ret; })
1411 static int scanelf_elfobj(elfobj *elf)
1412 {
1413 unsigned long i;
1414 char found_pax, found_phdr, found_relro, found_load, found_textrel,
1415 found_rpath, found_needed, found_interp, found_bind, found_soname,
1416 found_sym, found_lib, found_file, found_textrels, found_section;
1417 static char *out_buffer = NULL;
1418 static size_t out_len;
1419
1420 found_pax = found_phdr = found_relro = found_load = found_textrel = \
1421 found_rpath = found_needed = found_interp = found_bind = found_soname = \
1422 found_sym = found_lib = found_file = found_textrels = found_section = 0;
1423
1424 if (be_verbose > 2)
1425 printf("%s: scanning file {%s,%s}\n", elf->filename,
1426 get_elfeitype(EI_CLASS, elf->elf_class),
1427 get_elfeitype(EI_DATA, elf->data[EI_DATA]));
1428 else if (be_verbose > 1)
1429 printf("%s: scanning file\n", elf->filename);
1430
1431 /* init output buffer */
1432 if (!out_buffer) {
1433 out_len = sizeof(char) * 80;
1434 out_buffer = xmalloc(out_len);
1435 }
1436 *out_buffer = '\0';
1437
1438 /* show the header */
1439 if (!be_quiet && show_banner) {
1440 for (i = 0; out_format[i]; ++i) {
1441 if (!IS_MODIFIER(out_format[i])) continue;
1442
1443 switch (out_format[++i]) {
1444 case '+': break;
1445 case '%': break;
1446 case '#': break;
1447 case 'F':
1448 case 'p':
1449 case 'f': prints("FILE "); found_file = 1; break;
1450 case 'o': prints(" TYPE "); break;
1451 case 'x': prints(" PAX "); break;
1452 case 'e': prints("STK/REL/PTL "); break;
1453 case 't': prints("TEXTREL "); break;
1454 case 'r': prints("RPATH "); break;
1455 case 'M': prints("CLASS "); break;
1456 case 'l':
1457 case 'n': prints("NEEDED "); break;
1458 case 'i': prints("INTERP "); break;
1459 case 'b': prints("BIND "); break;
1460 case 'Z': prints("SIZE "); break;
1461 case 'S': prints("SONAME "); break;
1462 case 's': prints("SYM "); break;
1463 case 'N': prints("LIB "); break;
1464 case 'T': prints("TEXTRELS "); break;
1465 case 'k': prints("SECTION "); break;
1466 case 'a': prints("ARCH "); break;
1467 case 'I': prints("OSABI "); break;
1468 case 'Y': prints("EABI "); break;
1469 case 'O': prints("PERM "); break;
1470 case 'D': prints("ENDIAN "); break;
1471 default: warnf("'%c' has no title ?", out_format[i]);
1472 }
1473 }
1474 if (!found_file) prints("FILE ");
1475 prints("\n");
1476 found_file = 0;
1477 show_banner = 0;
1478 }
1479
1480 /* dump all the good stuff */
1481 for (i = 0; out_format[i]; ++i) {
1482 const char *out;
1483 const char *tmp;
1484 static char ubuf[sizeof(unsigned long)*2];
1485 if (!IS_MODIFIER(out_format[i])) {
1486 xchrcat(&out_buffer, out_format[i], &out_len);
1487 continue;
1488 }
1489
1490 out = NULL;
1491 be_wewy_wewy_quiet = (out_format[i] == '#');
1492 be_semi_verbose = (out_format[i] == '+');
1493 switch (out_format[++i]) {
1494 case '+':
1495 case '%':
1496 case '#':
1497 xchrcat(&out_buffer, out_format[i], &out_len); break;
1498 case 'F':
1499 found_file = 1;
1500 if (be_wewy_wewy_quiet) break;
1501 xstrcat(&out_buffer, elf->filename, &out_len);
1502 break;
1503 case 'p':
1504 found_file = 1;
1505 if (be_wewy_wewy_quiet) break;
1506 tmp = elf->filename;
1507 if (search_path) {
1508 ssize_t len_search = strlen(search_path);
1509 ssize_t len_file = strlen(elf->filename);
1510 if (!strncmp(elf->filename, search_path, len_search) && \
1511 len_file > len_search)
1512 tmp += len_search;
1513 if (*tmp == '/' && search_path[len_search-1] == '/') tmp++;
1514 }
1515 xstrcat(&out_buffer, tmp, &out_len);
1516 break;
1517 case 'f':
1518 found_file = 1;
1519 if (be_wewy_wewy_quiet) break;
1520 tmp = strrchr(elf->filename, '/');
1521 tmp = (tmp == NULL ? elf->filename : tmp+1);
1522 xstrcat(&out_buffer, tmp, &out_len);
1523 break;
1524 case 'o': out = get_elfetype(elf); break;
1525 case 'x': out = scanelf_file_pax(elf, &found_pax); break;
1526 case 'e': out = scanelf_file_phdr(elf, &found_phdr, &found_relro, &found_load); break;
1527 case 't': out = scanelf_file_textrel(elf, &found_textrel); break;
1528 case 'T': out = scanelf_file_textrels(elf, &found_textrels, &found_textrel); break;
1529 case 'r': scanelf_file_rpath(elf, &found_rpath, &out_buffer, &out_len); break;
1530 case 'M': out = get_elfeitype(EI_CLASS, elf->data[EI_CLASS]); break;
1531 case 'D': out = get_endian(elf); break;
1532 case 'O': out = strfileperms(elf->filename); break;
1533 case 'n':
1534 case 'N': out = scanelf_file_needed_lib(elf, &found_needed, &found_lib, (out_format[i]=='N'), &out_buffer, &out_len); break;
1535 case 'i': out = scanelf_file_interp(elf, &found_interp); break;
1536 case 'b': out = scanelf_file_bind(elf, &found_bind); break;
1537 case 'S': out = scanelf_file_soname(elf, &found_soname); break;
1538 case 's': out = scanelf_file_sym(elf, &found_sym); break;
1539 case 'k': out = scanelf_file_sections(elf, &found_section); break;
1540 case 'a': out = get_elfemtype(elf); break;
1541 case 'I': out = get_elfosabi(elf); break;
1542 case 'Y': out = get_elf_eabi(elf); break;
1543 case 'Z': snprintf(ubuf, sizeof(ubuf), "%lu", (unsigned long)elf->len); out = ubuf; break;;
1544 default: warnf("'%c' has no scan code?", out_format[i]);
1545 }
1546 if (out)
1547 xstrcat(&out_buffer, out, &out_len);
1548 }
1549
1550 #define FOUND_SOMETHING() \
1551 (found_pax || found_phdr || found_relro || found_load || found_textrel || \
1552 found_rpath || found_needed || found_interp || found_bind || \
1553 found_soname || found_sym || found_lib || found_textrels || found_section )
1554
1555 if (!found_file && (!be_quiet || (be_quiet && FOUND_SOMETHING()))) {
1556 xchrcat(&out_buffer, ' ', &out_len);
1557 xstrcat(&out_buffer, elf->filename, &out_len);
1558 }
1559 if (!be_quiet || (be_quiet && FOUND_SOMETHING())) {
1560 puts(out_buffer);
1561 fflush(stdout);
1562 }
1563
1564 return 0;
1565 }
1566
1567 /* scan a single elf */
1568 static int scanelf_elf(const char *filename, int fd, size_t len)
1569 {
1570 int ret = 1;
1571 elfobj *elf;
1572
1573 /* verify this is real ELF */
1574 if ((elf = _readelf_fd(filename, fd, len, !fix_elf)) == NULL) {
1575 if (be_verbose > 2) printf("%s: not an ELF\n", filename);
1576 return 2;
1577 }
1578 switch (match_bits) {
1579 case 32:
1580 if (elf->elf_class != ELFCLASS32)
1581 goto label_done;
1582 break;
1583 case 64:
1584 if (elf->elf_class != ELFCLASS64)
1585 goto label_done;
1586 break;
1587 default: break;
1588 }
1589 if (match_etypes) {
1590 char sbuf[126];
1591 strncpy(sbuf, match_etypes, sizeof(sbuf));
1592 if (strchr(match_etypes, ',') != NULL) {
1593 char *p;
1594 while ((p = strrchr(sbuf, ',')) != NULL) {
1595 *p = 0;
1596 if (etype_lookup(p+1) == get_etype(elf))
1597 goto label_ret;
1598 }
1599 }
1600 if (etype_lookup(sbuf) != get_etype(elf))
1601 goto label_done;
1602 }
1603
1604 label_ret:
1605 ret = scanelf_elfobj(elf);
1606
1607 label_done:
1608 unreadelf(elf);
1609 return ret;
1610 }
1611
1612 /* scan an archive of elfs */
1613 static int scanelf_archive(const char *filename, int fd, size_t len)
1614 {
1615 archive_handle *ar;
1616 archive_member *m;
1617 char *ar_buffer;
1618 elfobj *elf;
1619
1620 ar = ar_open_fd(filename, fd);
1621 if (ar == NULL)
1622 return 1;
1623
1624 ar_buffer = mmap(0, len, PROT_READ | (fix_elf ? PROT_WRITE : 0), (fix_elf ? MAP_SHARED : MAP_PRIVATE), fd, 0);
1625 while ((m = ar_next(ar)) != NULL) {
1626 off_t cur_pos = lseek(fd, 0, SEEK_CUR);
1627 if (cur_pos == -1)
1628 errp("lseek() failed");
1629 elf = readelf_buffer(m->name, ar_buffer + cur_pos, m->size);
1630 if (elf) {
1631 scanelf_elfobj(elf);
1632 unreadelf(elf);
1633 }
1634 }
1635 munmap(ar_buffer, len);
1636
1637 return 0;
1638 }
1639 /* scan a file which may be an elf or an archive or some other magical beast */
1640 static int scanelf_fileat(int dir_fd, const char *filename, const struct stat *st_cache)
1641 {
1642 const struct stat *st = st_cache;
1643 struct stat symlink_st;
1644 int fd;
1645
1646 /* always handle regular files and handle symlinked files if no -y */
1647 if (S_ISLNK(st->st_mode)) {
1648 if (!scan_symlink)
1649 return 1;
1650 fstatat(dir_fd, filename, &symlink_st, 0);
1651 st = &symlink_st;
1652 }
1653
1654 if (!S_ISREG(st->st_mode)) {
1655 if (be_verbose > 2) printf("%s: skipping non-file\n", filename);
1656 return 1;
1657 }
1658
1659 if (match_perms) {
1660 if ((st->st_mode | match_perms) != st->st_mode)
1661 return 1;
1662 }
1663 fd = openat(dir_fd, filename, (fix_elf ? O_RDWR : O_RDONLY) | O_CLOEXEC);
1664 if (fd == -1) {
1665 if (fix_elf && errno == ETXTBSY)
1666 warnp("%s: could not fix", filename);
1667 else if (be_verbose > 2)
1668 printf("%s: skipping file: %s\n", filename, strerror(errno));
1669 return 1;
1670 }
1671
1672 if (scanelf_elf(filename, fd, st->st_size) == 2) {
1673 /* if it isn't an ELF, maybe it's an .a archive */
1674 if (scan_archives)
1675 scanelf_archive(filename, fd, st->st_size);
1676
1677 /*
1678 * unreadelf() implicitly closes its fd, so only close it
1679 * when we are returning it in the non-ELF case
1680 */
1681 close(fd);
1682 }
1683
1684 return 0;
1685 }
1686
1687 /* scan a directory for ET_EXEC files and print when we find one */
1688 static int scanelf_dirat(int dir_fd, const char *path)
1689 {
1690 register DIR *dir;
1691 register struct dirent *dentry;
1692 struct stat st_top, st;
1693 char buf[__PAX_UTILS_PATH_MAX], *subpath;
1694 size_t pathlen = 0, len = 0;
1695 int ret = 0;
1696 int subdir_fd;
1697
1698 /* make sure path exists */
1699 if (fstatat(dir_fd, path, &st_top, AT_SYMLINK_NOFOLLOW) == -1) {
1700 if (be_verbose > 2) printf("%s: does not exist\n", path);
1701 return 1;
1702 }
1703
1704 /* ok, if it isn't a directory, assume we can open it */
1705 if (!S_ISDIR(st_top.st_mode))
1706 return scanelf_fileat(dir_fd, path, &st_top);
1707
1708 /* now scan the dir looking for fun stuff */
1709 subdir_fd = openat(dir_fd, path, O_RDONLY|O_CLOEXEC);
1710 if (subdir_fd == -1)
1711 dir = NULL;
1712 else
1713 dir = fdopendir(subdir_fd);
1714 if (dir == NULL) {
1715 if (subdir_fd != -1)
1716 close(subdir_fd);
1717 warnfp("could not opendir(%s)", path);
1718 return 1;
1719 }
1720 if (be_verbose > 1) printf("%s: scanning dir\n", path);
1721
1722 subpath = stpcpy(buf, path);
1723 if (subpath[-1] != '/')
1724 *subpath++ = '/';
1725 pathlen = subpath - buf;
1726 while ((dentry = readdir(dir))) {
1727 if (!strcmp(dentry->d_name, ".") || !strcmp(dentry->d_name, ".."))
1728 continue;
1729
1730 if (fstatat(subdir_fd, dentry->d_name, &st, AT_SYMLINK_NOFOLLOW) == -1)
1731 continue;
1732
1733 len = strlen(dentry->d_name);
1734 if (len + pathlen + 1 >= sizeof(buf)) {
1735 warnf("Skipping '%s%s': len > sizeof(buf); %zu > %zu\n",
1736 path, dentry->d_name, len + pathlen + 1, sizeof(buf));
1737 continue;
1738 }
1739 memcpy(subpath, dentry->d_name, len);
1740 subpath[len] = '\0';
1741
1742 if (S_ISREG(st.st_mode))
1743 ret = scanelf_fileat(dir_fd, buf, &st);
1744 else if (dir_recurse && S_ISDIR(st.st_mode)) {
1745 if (dir_crossmount || (st_top.st_dev == st.st_dev))
1746 ret = scanelf_dirat(dir_fd, buf);
1747 }
1748 }
1749 closedir(dir);
1750
1751 return ret;
1752 }
1753 static int scanelf_dir(const char *path)
1754 {
1755 return scanelf_dirat(root_fd, root_rel_path(path));
1756 }
1757
1758 static int scanelf_from_file(const char *filename)
1759 {
1760 FILE *fp;
1761 char *p, *path;
1762 size_t len;
1763 int ret;
1764
1765 if (strcmp(filename, "-") == 0)
1766 fp = stdin;
1767 else if ((fp = fopen(filename, "r")) == NULL)
1768 return 1;
1769
1770 path = NULL;
1771 len = 0;
1772 ret = 0;
1773 while (getline(&path, &len, fp) != -1) {
1774 if ((p = strchr(path, '\n')) != NULL)
1775 *p = 0;
1776 search_path = path;
1777 ret = scanelf_dir(path);
1778 }
1779 free(path);
1780
1781 if (fp != stdin)
1782 fclose(fp);
1783
1784 return ret;
1785 }
1786
1787 #if defined(__GLIBC__) || defined(__UCLIBC__) || defined(__NetBSD__)
1788
1789 static int _load_ld_cache_config(const char *fname)
1790 {
1791 FILE *fp = NULL;
1792 char *p, *path;
1793 size_t len;
1794 int curr_fd = -1;
1795
1796 fp = fopenat_r(root_fd, root_rel_path(fname));
1797 if (fp == NULL)
1798 return -1;
1799
1800 path = NULL;
1801 len = 0;
1802 while (getline(&path, &len, fp) != -1) {
1803 if ((p = strrchr(path, '\r')) != NULL)
1804 *p = 0;
1805 if ((p = strchr(path, '\n')) != NULL)
1806 *p = 0;
1807
1808 /* recursive includes of the same file will make this segfault. */
1809 if ((memcmp(path, "include", 7) == 0) && isblank(path[7])) {
1810 glob_t gl;
1811 size_t x;
1812 const char *gpath;
1813
1814 /* re-use existing path buffer ... need to be creative */
1815 if (path[8] != '/')
1816 gpath = memcpy(path + 3, "/etc/", 5);
1817 else
1818 gpath = path + 8;
1819 if (root_fd != AT_FDCWD) {
1820 if (curr_fd == -1) {
1821 curr_fd = open(".", O_RDONLY|O_CLOEXEC);
1822 if (fchdir(root_fd))
1823 errp("unable to change to root dir");
1824 }
1825 gpath = root_rel_path(gpath);
1826 }
1827
1828 if (glob(gpath, 0, NULL, &gl) == 0) {
1829 for (x = 0; x < gl.gl_pathc; ++x) {
1830 /* try to avoid direct loops */
1831 if (strcmp(gl.gl_pathv[x], fname) == 0)
1832 continue;
1833 _load_ld_cache_config(gl.gl_pathv[x]);
1834 }
1835 globfree(&gl);
1836 }
1837
1838 /* failed globs are ignored by glibc */
1839 continue;
1840 }
1841
1842 if (*path != '/')
1843 continue;
1844
1845 xarraypush_str(ldpaths, path);
1846 }
1847 free(path);
1848
1849 fclose(fp);
1850
1851 if (curr_fd != -1) {
1852 if (fchdir(curr_fd))
1853 /* don't care */;
1854 close(curr_fd);
1855 }
1856
1857 return 0;
1858 }
1859
1860 #elif defined(__FreeBSD__) || defined(__DragonFly__)
1861
1862 static int _load_ld_cache_config(const char *fname)
1863 {
1864 FILE *fp = NULL;
1865 char *b = NULL, *p;
1866 struct elfhints_hdr hdr;
1867
1868 fp = fopenat_r(root_fd, root_rel_path(fname));
1869 if (fp == NULL)
1870 return -1;
1871
1872 if (fread(&hdr, 1, sizeof(hdr), fp) != sizeof(hdr) ||
1873 hdr.magic != ELFHINTS_MAGIC || hdr.version != 1 ||
1874 fseek(fp, hdr.strtab + hdr.dirlist, SEEK_SET) == -1)
1875 {
1876 fclose(fp);
1877 return -1;
1878 }
1879
1880 b = xmalloc(hdr.dirlistlen + 1);
1881 if (fread(b, 1, hdr.dirlistlen+1, fp) != hdr.dirlistlen+1) {
1882 fclose(fp);
1883 free(b);
1884 return -1;
1885 }
1886
1887 while ((p = strsep(&b, ":"))) {
1888 if (*p == '\0')
1889 continue;
1890 xarraypush_str(ldpaths, p);
1891 }
1892
1893 free(b);
1894 fclose(fp);
1895 return 0;
1896 }
1897
1898 #else
1899 #ifdef __ELF__
1900 #warning Cache config support not implemented for your target
1901 #endif
1902 static int _load_ld_cache_config(const char *fname)
1903 {
1904 return 0;
1905 }
1906 #endif
1907
1908 static void load_ld_cache_config(const char *fname)
1909 {
1910 bool scan_l, scan_ul, scan_ull;
1911 size_t n;
1912 const char *ldpath;
1913
1914 _load_ld_cache_config(fname);
1915
1916 scan_l = scan_ul = scan_ull = false;
1917 if (array_cnt(ldpaths)) {
1918 array_for_each(ldpaths, n, ldpath) {
1919 if (!scan_l && !strcmp(ldpath, "/lib")) scan_l = true;
1920 if (!scan_ul && !strcmp(ldpath, "/usr/lib")) scan_ul = true;
1921 if (!scan_ull && !strcmp(ldpath, "/usr/local/lib")) scan_ull = true;
1922 }
1923 }
1924
1925 if (!scan_l) xarraypush_str(ldpaths, "/lib");
1926 if (!scan_ul) xarraypush_str(ldpaths, "/usr/lib");
1927 if (!scan_ull) xarraypush_str(ldpaths, "/usr/local/lib");
1928 }
1929
1930 /* scan /etc/ld.so.conf for paths */
1931 static void scanelf_ldpath(void)
1932 {
1933 size_t n;
1934 const char *ldpath;
1935
1936 array_for_each(ldpaths, n, ldpath)
1937 scanelf_dir(ldpath);
1938 }
1939
1940 /* scan env PATH for paths */
1941 static void scanelf_envpath(void)
1942 {
1943 char *path, *p;
1944
1945 path = getenv("PATH");
1946 if (!path)
1947 err("PATH is not set in your env !");
1948 path = xstrdup(path);
1949
1950 while ((p = strrchr(path, ':')) != NULL) {
1951 scanelf_dir(p + 1);
1952 *p = 0;
1953 }
1954
1955 free(path);
1956 }
1957
1958 /* usage / invocation handling functions */ /* Free Flags: c d j u w G H J K P Q U W */
1959 #define PARSE_FLAGS "plRmyAXz:xetrnLibSs:k:gN:TaqvF:f:o:E:M:DIYO:ZCBhV"
1960 #define a_argument required_argument
1961 static struct option const long_opts[] = {
1962 {"path", no_argument, NULL, 'p'},
1963 {"ldpath", no_argument, NULL, 'l'},
1964 {"use-ldpath",no_argument, NULL, 129},
1965 {"root", a_argument, NULL, 128},
1966 {"recursive", no_argument, NULL, 'R'},
1967 {"mount", no_argument, NULL, 'm'},
1968 {"symlink", no_argument, NULL, 'y'},
1969 {"archives", no_argument, NULL, 'A'},
1970 {"ldcache", no_argument, NULL, 'L'},
1971 {"fix", no_argument, NULL, 'X'},
1972 {"setpax", a_argument, NULL, 'z'},
1973 {"pax", no_argument, NULL, 'x'},
1974 {"header", no_argument, NULL, 'e'},
1975 {"textrel", no_argument, NULL, 't'},
1976 {"rpath", no_argument, NULL, 'r'},
1977 {"needed", no_argument, NULL, 'n'},
1978 {"interp", no_argument, NULL, 'i'},
1979 {"bind", no_argument, NULL, 'b'},
1980 {"soname", no_argument, NULL, 'S'},
1981 {"symbol", a_argument, NULL, 's'},
1982 {"section", a_argument, NULL, 'k'},
1983 {"lib", a_argument, NULL, 'N'},
1984 {"gmatch", no_argument, NULL, 'g'},
1985 {"textrels", no_argument, NULL, 'T'},
1986 {"etype", a_argument, NULL, 'E'},
1987 {"bits", a_argument, NULL, 'M'},
1988 {"endian", no_argument, NULL, 'D'},
1989 {"osabi", no_argument, NULL, 'I'},
1990 {"eabi", no_argument, NULL, 'Y'},
1991 {"perms", a_argument, NULL, 'O'},
1992 {"size", no_argument, NULL, 'Z'},
1993 {"all", no_argument, NULL, 'a'},
1994 {"quiet", no_argument, NULL, 'q'},
1995 {"verbose", no_argument, NULL, 'v'},
1996 {"format", a_argument, NULL, 'F'},
1997 {"from", a_argument, NULL, 'f'},
1998 {"file", a_argument, NULL, 'o'},
1999 {"nocolor", no_argument, NULL, 'C'},
2000 {"nobanner", no_argument, NULL, 'B'},
2001 {"help", no_argument, NULL, 'h'},
2002 {"version", no_argument, NULL, 'V'},
2003 {NULL, no_argument, NULL, 0x0}
2004 };
2005
2006 static const char * const opts_help[] = {
2007 "Scan all directories in PATH environment",
2008 "Scan all directories in /etc/ld.so.conf",
2009 "Use ld.so.conf to show full path (use with -r/-n)",
2010 "Root directory (use with -l or -p)",
2011 "Scan directories recursively",
2012 "Don't recursively cross mount points",
2013 "Don't scan symlinks",
2014 "Scan archives (.a files)",
2015 "Utilize ld.so.cache to show full path (use with -r/-n)",
2016 "Try and 'fix' bad things (use with -r/-e)",
2017 "Sets EI_PAX/PT_PAX_FLAGS to <arg> (use with -Xx)\n",
2018 "Print PaX markings",
2019 "Print GNU_STACK/PT_LOAD markings",
2020 "Print TEXTREL information",
2021 "Print RPATH information",
2022 "Print NEEDED information",
2023 "Print INTERP information",
2024 "Print BIND information",
2025 "Print SONAME information",
2026 "Find a specified symbol",
2027 "Find a specified section",
2028 "Find a specified library",
2029 "Use regex matching rather than string compare (use with -s)",
2030 "Locate cause of TEXTREL",
2031 "Print only ELF files matching etype ET_DYN,ET_EXEC ...",
2032 "Print only ELF files matching numeric bits",
2033 "Print Endianness",
2034 "Print OSABI",
2035 "Print EABI (EM_ARM Only)",
2036 "Print only ELF files matching octal permissions",
2037 "Print ELF file size",
2038 "Print all useful/simple info\n",
2039 "Only output 'bad' things",
2040 "Be verbose (can be specified more than once)",
2041 "Use specified format for output",
2042 "Read input stream from a filename",
2043 "Write output stream to a filename",
2044 "Don't emit color in output",
2045 "Don't display the header",
2046 "Print this help and exit",
2047 "Print version and exit",
2048 NULL
2049 };
2050
2051 /* display usage and exit */
2052 static void usage(int status)
2053 {
2054 unsigned long i;
2055 printf("* Scan ELF binaries for stuff\n\n"
2056 "Usage: %s [options] <dir1/file1> [dir2 dirN file2 fileN ...]\n\n", argv0);
2057 printf("Options: -[%s]\n", PARSE_FLAGS);
2058 for (i = 0; long_opts[i].name; ++i) {
2059 /* first output the short flag if it has one */
2060 if (long_opts[i].val > '~')
2061 printf(" ");
2062 else
2063 printf(" -%c, ", long_opts[i].val);
2064
2065 /* then the long flag */
2066 if (long_opts[i].has_arg == no_argument)
2067 printf("--%-14s", long_opts[i].name);
2068 else
2069 printf("--%-7s <arg> ", long_opts[i].name);
2070
2071 /* finally the help text */
2072 printf("* %s\n", opts_help[i]);
2073 }
2074
2075 puts("\nFor more information, see the scanelf(1) manpage");
2076 exit(status);
2077 }
2078
2079 /* parse command line arguments and preform needed actions */
2080 #define do_pax_state(option, flag) \
2081 if (islower(option)) { \
2082 flags &= ~PF_##flag; \
2083 flags |= PF_NO##flag; \
2084 } else { \
2085 flags &= ~PF_NO##flag; \
2086 flags |= PF_##flag; \
2087 }
2088 static int parseargs(int argc, char *argv[])
2089 {
2090 int i;
2091 const char *from_file = NULL;
2092 int ret = 0;
2093 char load_cache_config = 0;
2094
2095 opterr = 0;
2096 while ((i=getopt_long(argc, argv, PARSE_FLAGS, long_opts, NULL)) != -1) {
2097 switch (i) {
2098
2099 case 'V':
2100 printf("pax-utils-%s: %s compiled %s\n%s\n"
2101 "%s written for Gentoo by <solar and vapier @ gentoo.org>\n",
2102 VERSION, __FILE__, __DATE__, rcsid, argv0);
2103 exit(EXIT_SUCCESS);
2104 break;
2105 case 'h': usage(EXIT_SUCCESS); break;
2106 case 'f':
2107 if (from_file) warn("You prob don't want to specify -f twice");
2108 from_file = optarg;
2109 break;
2110 case 'E':
2111 match_etypes = optarg;
2112 break;
2113 case 'M':
2114 match_bits = atoi(optarg);
2115 if (match_bits == 0) {
2116 if (strcmp(optarg, "ELFCLASS32") == 0)
2117 match_bits = 32;
2118 if (strcmp(optarg, "ELFCLASS64") == 0)
2119 match_bits = 64;
2120 }
2121 break;
2122 case 'O':
2123 if (sscanf(optarg, "%o", &match_perms) == -1)
2124 match_bits = 0;
2125 break;
2126 case 'o': {
2127 if (freopen(optarg, "w", stdout) == NULL)
2128 errp("Could not freopen(%s)", optarg);
2129 break;
2130 }
2131 case 'k':
2132 xarraypush_str(find_section_arr, optarg);
2133 break;
2134 case 's': {
2135 if (find_sym) warn("You prob don't want to specify -s twice");
2136 find_sym = optarg;
2137 break;
2138 }
2139 case 'N':
2140 xarraypush_str(find_lib_arr, optarg);
2141 break;
2142 case 'F': {
2143 if (out_format) warn("You prob don't want to specify -F twice");
2144 out_format = optarg;
2145 break;
2146 }
2147 case 'z': {
2148 unsigned long flags = (PF_NOEMUTRAMP | PF_NORANDEXEC);
2149 size_t x;
2150
2151 for (x = 0; x < strlen(optarg); x++) {
2152 switch (optarg[x]) {
2153 case 'p':
2154 case 'P':
2155 do_pax_state(optarg[x], PAGEEXEC);
2156 break;
2157 case 's':
2158 case 'S':
2159 do_pax_state(optarg[x], SEGMEXEC);
2160 break;
2161 case 'm':
2162 case 'M':
2163 do_pax_state(optarg[x], MPROTECT);
2164 break;
2165 case 'e':
2166 case 'E':
2167 do_pax_state(optarg[x], EMUTRAMP);
2168 break;
2169 case 'r':
2170 case 'R':
2171 do_pax_state(optarg[x], RANDMMAP);
2172 break;
2173 case 'x':
2174 case 'X':
2175 do_pax_state(optarg[x], RANDEXEC);
2176 break;
2177 default:
2178 break;
2179 }
2180 }
2181 if (!(((flags & PF_PAGEEXEC) && (flags & PF_NOPAGEEXEC)) ||
2182 ((flags & PF_SEGMEXEC) && (flags & PF_NOSEGMEXEC)) ||
2183 ((flags & PF_RANDMMAP) && (flags & PF_NORANDMMAP)) ||
2184 ((flags & PF_RANDEXEC) && (flags & PF_NORANDEXEC)) ||
2185 ((flags & PF_EMUTRAMP) && (flags & PF_NOEMUTRAMP)) ||
2186 ((flags & PF_RANDMMAP) && (flags & PF_NORANDMMAP))))
2187 setpax = flags;
2188 break;
2189 }
2190 case 'Z': show_size = 1; break;
2191 case 'g': g_match = 1; break;
2192 case 'L': load_cache_config = use_ldcache = 1; break;
2193 case 'y': scan_symlink = 0; break;
2194 case 'A': scan_archives = 1; break;
2195 case 'C': color_init(true); break;
2196 case 'B': show_banner = 0; break;
2197 case 'l': load_cache_config = scan_ldpath = 1; break;
2198 case 'p': scan_envpath = 1; break;
2199 case 'R': dir_recurse = 1; break;
2200 case 'm': dir_crossmount = 0; break;
2201 case 'X': ++fix_elf; break;
2202 case 'x': show_pax = 1; break;
2203 case 'e': show_phdr = 1; break;
2204 case 't': show_textrel = 1; break;
2205 case 'r': show_rpath = 1; break;
2206 case 'n': show_needed = 1; break;
2207 case 'i': show_interp = 1; break;
2208 case 'b': show_bind = 1; break;
2209 case 'S': show_soname = 1; break;
2210 case 'T': show_textrels = 1; break;
2211 case 'q': be_quiet = 1; break;
2212 case 'v': be_verbose = (be_verbose % 20) + 1; break;
2213 case 'a': show_perms = show_pax = show_phdr = show_textrel = show_rpath = show_bind = show_endian = 1; break;
2214 case 'D': show_endian = 1; break;
2215 case 'I': show_osabi = 1; break;
2216 case 'Y': show_eabi = 1; break;
2217 case 128:
2218 root_fd = open(optarg, O_RDONLY|O_CLOEXEC);
2219 if (root_fd == -1)
2220 err("Could not open root: %s", optarg);
2221 break;
2222 case 129: load_cache_config = use_ldpath = 1; break;
2223 case ':':
2224 err("Option '%c' is missing parameter", optopt);
2225 case '?':
2226 err("Unknown option '%c' or argument missing", optopt);
2227 default:
2228 err("Unhandled option '%c'; please report this", i);
2229 }
2230 }
2231 if (show_textrels && be_verbose)
2232 has_objdump = bin_in_path("objdump");
2233 /* flatten arrays for display */
2234 if (array_cnt(find_lib_arr))
2235 find_lib = array_flatten_str(find_lib_arr);
2236 if (array_cnt(find_section_arr))
2237 find_section = array_flatten_str(find_section_arr);
2238 /* let the format option override all other options */
2239 if (out_format) {
2240 show_pax = show_phdr = show_textrel = show_rpath = \
2241 show_needed = show_interp = show_bind = show_soname = \
2242 show_textrels = show_perms = show_endian = show_size = \
2243 show_osabi = show_eabi = 0;
2244 for (i = 0; out_format[i]; ++i) {
2245 if (!IS_MODIFIER(out_format[i])) continue;
2246
2247 switch (out_format[++i]) {
2248 case '+': break;
2249 case '%': break;
2250 case '#': break;
2251 case 'F': break;
2252 case 'p': break;
2253 case 'f': break;
2254 case 'k': break;
2255 case 's': break;
2256 case 'N': break;
2257 case 'o': break;
2258 case 'a': break;
2259 case 'M': break;
2260 case 'Z': show_size = 1; break;
2261 case 'D': show_endian = 1; break;
2262 case 'I': show_osabi = 1; break;
2263 case 'Y': show_eabi = 1; break;
2264 case 'O': show_perms = 1; break;
2265 case 'x': show_pax = 1; break;
2266 case 'e': show_phdr = 1; break;
2267 case 't': show_textrel = 1; break;
2268 case 'r': show_rpath = 1; break;
2269 case 'n': show_needed = 1; break;
2270 case 'i': show_interp = 1; break;
2271 case 'b': show_bind = 1; break;
2272 case 'S': show_soname = 1; break;
2273 case 'T': show_textrels = 1; break;
2274 default:
2275 err("invalid format specifier '%c' (byte %i)",
2276 out_format[i], i+1);
2277 }
2278 }
2279
2280 /* construct our default format */
2281 } else {
2282 size_t fmt_len = 30;
2283 out_format = xmalloc(sizeof(char) * fmt_len);
2284 *out_format = '\0';
2285 if (!be_quiet) xstrcat(&out_format, "%o ", &fmt_len);
2286 if (show_pax) xstrcat(&out_format, "%x ", &fmt_len);
2287 if (show_perms) xstrcat(&out_format, "%O ", &fmt_len);
2288 if (show_size) xstrcat(&out_format, "%Z ", &fmt_len);
2289 if (show_endian) xstrcat(&out_format, "%D ", &fmt_len);
2290 if (show_osabi) xstrcat(&out_format, "%I ", &fmt_len);
2291 if (show_eabi) xstrcat(&out_format, "%Y ", &fmt_len);
2292 if (show_phdr) xstrcat(&out_format, "%e ", &fmt_len);
2293 if (show_textrel) xstrcat(&out_format, "%t ", &fmt_len);
2294 if (show_rpath) xstrcat(&out_format, "%r ", &fmt_len);
2295 if (show_needed) xstrcat(&out_format, "%n ", &fmt_len);
2296 if (show_interp) xstrcat(&out_format, "%i ", &fmt_len);
2297 if (show_bind) xstrcat(&out_format, "%b ", &fmt_len);
2298 if (show_soname) xstrcat(&out_format, "%S ", &fmt_len);
2299 if (show_textrels) xstrcat(&out_format, "%T ", &fmt_len);
2300 if (find_sym) xstrcat(&out_format, "%s ", &fmt_len);
2301 if (find_section) xstrcat(&out_format, "%k ", &fmt_len);
2302 if (find_lib) xstrcat(&out_format, "%N ", &fmt_len);
2303 if (!be_quiet) xstrcat(&out_format, "%F ", &fmt_len);
2304 }
2305 if (be_verbose > 2) printf("Format: %s\n", out_format);
2306
2307 /* now lets actually do the scanning */
2308 if (load_cache_config)
2309 load_ld_cache_config(__PAX_UTILS_DEFAULT_LD_CACHE_CONFIG);
2310 if (scan_ldpath) scanelf_ldpath();
2311 if (scan_envpath) scanelf_envpath();
2312 if (!from_file && optind == argc && ttyname(0) == NULL && !scan_ldpath && !scan_envpath)
2313 from_file = "-";
2314 if (from_file) {
2315 scanelf_from_file(from_file);
2316 from_file = *argv;
2317 }
2318 if (optind == argc && !scan_ldpath && !scan_envpath && !from_file)
2319 err("Nothing to scan !?");
2320 while (optind < argc) {
2321 search_path = argv[optind++];
2322 ret = scanelf_dir(search_path);
2323 }
2324
2325 /* clean up */
2326 xarrayfree(ldpaths);
2327 xarrayfree(find_lib_arr);
2328 xarrayfree(find_section_arr);
2329 free(find_lib);
2330 free(find_section);
2331
2332 if (ldcache != 0)
2333 munmap(ldcache, ldcache_size);
2334 return ret;
2335 }
2336
2337 static char **get_split_env(const char *envvar)
2338 {
2339 const char *delims = " \t\n";
2340 char **envvals = NULL;
2341 char *env, *s;
2342 int nentry;
2343
2344 if ((env = getenv(envvar)) == NULL)
2345 return NULL;
2346
2347 env = xstrdup(env);
2348 if (env == NULL)
2349 return NULL;
2350
2351 s = strtok(env, delims);
2352 if (s == NULL) {
2353 free(env);
2354 return NULL;
2355 }
2356
2357 nentry = 0;
2358 while (s != NULL) {
2359 ++nentry;
2360 envvals = xrealloc(envvals, sizeof(*envvals) * (nentry+1));
2361 envvals[nentry-1] = s;
2362 s = strtok(NULL, delims);
2363 }
2364 envvals[nentry] = NULL;
2365
2366 /* don't want to free(env) as it contains the memory that backs
2367 * the envvals array of strings */
2368 return envvals;
2369 }
2370
2371 static void parseenv(void)
2372 {
2373 color_init(false);
2374 qa_textrels = get_split_env("QA_TEXTRELS");
2375 qa_execstack = get_split_env("QA_EXECSTACK");
2376 qa_wx_load = get_split_env("QA_WX_LOAD");
2377 }
2378
2379 #ifdef __PAX_UTILS_CLEANUP
2380 static void cleanup(void)
2381 {
2382 free(out_format);
2383 free(qa_textrels);
2384 free(qa_execstack);
2385 free(qa_wx_load);
2386 }
2387 #endif
2388
2389 int main(int argc, char *argv[])
2390 {
2391 int ret;
2392 if (argc < 2)
2393 usage(EXIT_FAILURE);
2394 parseenv();
2395 ret = parseargs(argc, argv);
2396 fclose(stdout);
2397 #ifdef __PAX_UTILS_CLEANUP
2398 cleanup();
2399 warn("The calls to add/delete heap should be off:\n"
2400 "\t- 1 due to the out_buffer not being freed in scanelf_fileat()\n"
2401 "\t- 1 per QA_TEXTRELS/QA_EXECSTACK/QA_WX_LOAD");
2402 #endif
2403 return ret;
2404 }
2405
2406 /* Match filename against entries in matchlist, return TRUE
2407 * if the file is listed */
2408 static int file_matches_list(const char *filename, char **matchlist)
2409 {
2410 char **file;
2411 char *match;
2412 char buf[__PAX_UTILS_PATH_MAX];
2413
2414 if (matchlist == NULL)
2415 return 0;
2416
2417 for (file = matchlist; *file != NULL; file++) {
2418 if (search_path) {
2419 snprintf(buf, sizeof(buf), "%s%s", search_path, *file);
2420 match = buf;
2421 } else {
2422 match = *file;
2423 }
2424 if (fnmatch(match, filename, 0) == 0)
2425 return 1;
2426 }
2427 return 0;
2428 }

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