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Revision 1.240 - (show annotations) (download) (as text)
Mon Jan 23 23:48:54 2012 UTC (2 years, 6 months ago) by vapier
Branch: MAIN
Changes since 1.239: +69 -38 lines
File MIME type: text/x-csrc
add --use-ldpath option that considers ld.so.conf when outputting full paths for %n

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 1.239 2012/01/23 22:28:17 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 1.239 2012/01/23 22:28:17 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 #define GET_SYMTABS(B) \
159 if (elf->elf_class == ELFCLASS ## B) { \
160 if (symtab && dynsym) { \
161 Elf ## B ## _Shdr *esymtab = symtab; \
162 Elf ## B ## _Shdr *edynsym = dynsym; \
163 *sym = (EGET(esymtab->sh_size) > EGET(edynsym->sh_size)) ? symtab : dynsym; \
164 } else \
165 *sym = symtab ? symtab : dynsym; \
166 if (strtab && dynstr) { \
167 Elf ## B ## _Shdr *estrtab = strtab; \
168 Elf ## B ## _Shdr *edynstr = dynstr; \
169 *str = (EGET(estrtab->sh_size) > EGET(edynstr->sh_size)) ? strtab : dynstr; \
170 } else \
171 *str = strtab ? strtab : dynstr; \
172 }
173 GET_SYMTABS(32)
174 GET_SYMTABS(64)
175
176 if (*sym && *str)
177 return;
178
179 /*
180 * damn, they're really going to make us work for it huh?
181 * reconstruct the section header info out of the dynamic
182 * tags so we can see what symbols this guy uses at runtime.
183 */
184 #define GET_SYMTABS_DT(B) \
185 if (elf->elf_class == ELFCLASS ## B) { \
186 size_t i; \
187 static Elf ## B ## _Shdr sym_shdr, str_shdr; \
188 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
189 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
190 Elf ## B ## _Addr vsym, vstr, vhash, vgnu_hash; \
191 Elf ## B ## _Dyn *dyn; \
192 Elf ## B ## _Off offset; \
193 \
194 /* lookup symbols used at runtime with DT_SYMTAB / DT_STRTAB */ \
195 vsym = vstr = vhash = vgnu_hash = 0; \
196 memset(&sym_shdr, 0, sizeof(sym_shdr)); \
197 memset(&str_shdr, 0, sizeof(str_shdr)); \
198 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
199 if (EGET(phdr[i].p_type) != PT_DYNAMIC) \
200 continue; \
201 \
202 offset = EGET(phdr[i].p_offset); \
203 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) \
204 continue; \
205 \
206 dyn = DYN ## B (elf->vdata + offset); \
207 while (EGET(dyn->d_tag) != DT_NULL) { \
208 switch (EGET(dyn->d_tag)) { \
209 case DT_SYMTAB: vsym = EGET(dyn->d_un.d_val); break; \
210 case DT_SYMENT: sym_shdr.sh_entsize = dyn->d_un.d_val; break; \
211 case DT_STRTAB: vstr = EGET(dyn->d_un.d_val); break; \
212 case DT_STRSZ: str_shdr.sh_size = dyn->d_un.d_val; break; \
213 case DT_HASH: vhash = EGET(dyn->d_un.d_val); break; \
214 /*case DT_GNU_HASH: vgnu_hash = EGET(dyn->d_un.d_val); break;*/ \
215 } \
216 ++dyn; \
217 } \
218 if (vsym && vstr) \
219 break; \
220 } \
221 if (!vsym || !vstr || !(vhash || vgnu_hash)) \
222 return; \
223 \
224 /* calc offset into the ELF by finding the load addr of the syms */ \
225 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
226 Elf ## B ## _Addr vaddr = EGET(phdr[i].p_vaddr); \
227 Elf ## B ## _Addr filesz = EGET(phdr[i].p_filesz); \
228 offset = EGET(phdr[i].p_offset); \
229 \
230 if (EGET(phdr[i].p_type) != PT_LOAD) \
231 continue; \
232 \
233 if (vhash >= vaddr && vhash < vaddr + filesz) { \
234 /* Scan the hash table to see how many entries we have */ \
235 Elf32_Word max_sym_idx = 0; \
236 Elf32_Word *hashtbl = elf->vdata + offset + (vhash - vaddr); \
237 Elf32_Word b, nbuckets = EGET(hashtbl[0]); \
238 Elf32_Word nchains = EGET(hashtbl[1]); \
239 Elf32_Word *buckets = &hashtbl[2]; \
240 Elf32_Word *chains = &buckets[nbuckets]; \
241 Elf32_Word sym_idx; \
242 \
243 for (b = 0; b < nbuckets; ++b) { \
244 if (!buckets[b]) \
245 continue; \
246 for (sym_idx = buckets[b]; sym_idx < nchains && sym_idx; sym_idx = chains[sym_idx]) \
247 if (max_sym_idx < sym_idx) \
248 max_sym_idx = sym_idx; \
249 } \
250 ESET(sym_shdr.sh_size, sym_shdr.sh_entsize * max_sym_idx); \
251 } \
252 \
253 if (vsym >= vaddr && vsym < vaddr + filesz) { \
254 ESET(sym_shdr.sh_offset, offset + (vsym - vaddr)); \
255 *sym = &sym_shdr; \
256 } \
257 \
258 if (vstr >= vaddr && vstr < vaddr + filesz) { \
259 ESET(str_shdr.sh_offset, offset + (vstr - vaddr)); \
260 *str = &str_shdr; \
261 } \
262 } \
263 }
264 GET_SYMTABS_DT(32)
265 GET_SYMTABS_DT(64)
266 }
267
268 static char *scanelf_file_pax(elfobj *elf, char *found_pax)
269 {
270 static char ret[7];
271 unsigned long i, shown;
272
273 if (!show_pax) return NULL;
274
275 shown = 0;
276 memset(&ret, 0, sizeof(ret));
277
278 if (elf->phdr) {
279 #define SHOW_PAX(B) \
280 if (elf->elf_class == ELFCLASS ## B) { \
281 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
282 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
283 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
284 if (EGET(phdr[i].p_type) != PT_PAX_FLAGS) \
285 continue; \
286 if (fix_elf && setpax) { \
287 /* set the paxctl flags */ \
288 ESET(phdr[i].p_flags, setpax); \
289 } \
290 if (be_quiet && (EGET(phdr[i].p_flags) == (PF_NOEMUTRAMP | PF_NORANDEXEC))) \
291 continue; \
292 memcpy(ret, pax_short_pf_flags(EGET(phdr[i].p_flags)), 6); \
293 *found_pax = 1; \
294 ++shown; \
295 break; \
296 } \
297 }
298 SHOW_PAX(32)
299 SHOW_PAX(64)
300 }
301
302 if (fix_elf && setpax) {
303 /* set the chpax settings */
304 if (elf->elf_class == ELFCLASS32) {
305 if (EHDR32(elf->ehdr)->e_type == ET_DYN || EHDR32(elf->ehdr)->e_type == ET_EXEC)
306 ESET(EHDR32(elf->ehdr)->e_ident[EI_PAX], pax_pf2hf_flags(setpax));
307 } else {
308 if (EHDR64(elf->ehdr)->e_type == ET_DYN || EHDR64(elf->ehdr)->e_type == ET_EXEC)
309 ESET(EHDR64(elf->ehdr)->e_ident[EI_PAX], pax_pf2hf_flags(setpax));
310 }
311 }
312
313 /* fall back to EI_PAX if no PT_PAX was found */
314 if (!*ret) {
315 static char *paxflags;
316 paxflags = pax_short_hf_flags(EI_PAX_FLAGS(elf));
317 if (!be_quiet || (be_quiet && EI_PAX_FLAGS(elf))) {
318 *found_pax = 1;
319 return (be_wewy_wewy_quiet ? NULL : paxflags);
320 }
321 strncpy(ret, paxflags, sizeof(ret));
322 }
323
324 if (be_wewy_wewy_quiet || (be_quiet && !shown))
325 return NULL;
326 else
327 return ret;
328 }
329
330 static char *scanelf_file_phdr(elfobj *elf, char *found_phdr, char *found_relro, char *found_load)
331 {
332 static char ret[12];
333 char *found;
334 unsigned long i, shown, multi_stack, multi_relro, multi_load;
335 int max_pt_load;
336
337 if (!show_phdr) return NULL;
338
339 memcpy(ret, "--- --- ---\0", 12);
340
341 shown = 0;
342 multi_stack = multi_relro = multi_load = 0;
343 max_pt_load = elf_max_pt_load(elf);
344
345 #define NOTE_GNU_STACK ".note.GNU-stack"
346 #define SHOW_PHDR(B) \
347 if (elf->elf_class == ELFCLASS ## B) { \
348 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
349 Elf ## B ## _Off offset; \
350 uint32_t flags, check_flags; \
351 if (elf->phdr != NULL) { \
352 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
353 for (i = 0; i < EGET(ehdr->e_phnum); ++i) { \
354 if (EGET(phdr[i].p_type) == PT_GNU_STACK) { \
355 if (multi_stack++) \
356 warnf("%s: multiple PT_GNU_STACK's !?", elf->filename); \
357 if (file_matches_list(elf->filename, qa_execstack)) \
358 continue; \
359 found = found_phdr; \
360 offset = 0; \
361 check_flags = PF_X; \
362 } else if (EGET(phdr[i].p_type) == PT_GNU_RELRO) { \
363 if (multi_relro++) \
364 warnf("%s: multiple PT_GNU_RELRO's !?", elf->filename); \
365 found = found_relro; \
366 offset = 4; \
367 check_flags = PF_X; \
368 } else if (EGET(phdr[i].p_type) == PT_LOAD) { \
369 if (EGET(ehdr->e_type) == ET_DYN || EGET(ehdr->e_type) == ET_EXEC) \
370 if (multi_load++ > max_pt_load) \
371 warnf("%s: more than %i PT_LOAD's !?", elf->filename, max_pt_load); \
372 if (file_matches_list(elf->filename, qa_wx_load)) \
373 continue; \
374 found = found_load; \
375 offset = 8; \
376 check_flags = PF_W|PF_X; \
377 } else \
378 continue; \
379 flags = EGET(phdr[i].p_flags); \
380 if (be_quiet && ((flags & check_flags) != check_flags)) \
381 continue; \
382 if ((EGET(phdr[i].p_type) != PT_LOAD) && (fix_elf && ((flags & PF_X) != flags))) { \
383 ESET(phdr[i].p_flags, flags & (PF_X ^ (size_t)-1)); \
384 ret[3] = ret[7] = '!'; \
385 flags = EGET(phdr[i].p_flags); \
386 } \
387 memcpy(ret+offset, gnu_short_stack_flags(flags), 3); \
388 *found = 1; \
389 ++shown; \
390 } \
391 } else if (elf->shdr != NULL) { \
392 /* no program headers which means this is prob an object file */ \
393 Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \
394 Elf ## B ## _Shdr *strtbl = shdr + EGET(ehdr->e_shstrndx); \
395 char *str; \
396 if ((void*)strtbl > elf->data_end) \
397 goto skip_this_shdr##B; \
398 check_flags = SHF_WRITE|SHF_EXECINSTR; \
399 for (i = 0; i < EGET(ehdr->e_shnum); ++i) { \
400 if (EGET(shdr[i].sh_type) != SHT_PROGBITS) continue; \
401 offset = EGET(strtbl->sh_offset) + EGET(shdr[i].sh_name); \
402 str = elf->data + offset; \
403 if (str > elf->data + offset + sizeof(NOTE_GNU_STACK)) continue; \
404 if (!strcmp(str, NOTE_GNU_STACK)) { \
405 if (multi_stack++) warnf("%s: multiple .note.GNU-stack's !?", elf->filename); \
406 flags = EGET(shdr[i].sh_flags); \
407 if (be_quiet && ((flags & check_flags) != check_flags)) \
408 continue; \
409 ++*found_phdr; \
410 shown = 1; \
411 if (flags & SHF_WRITE) ret[0] = 'W'; \
412 if (flags & SHF_ALLOC) ret[1] = 'A'; \
413 if (flags & SHF_EXECINSTR) ret[2] = 'X'; \
414 if (flags & 0xFFFFFFF8) warn("Invalid section flags for GNU-stack"); \
415 break; \
416 } \
417 } \
418 skip_this_shdr##B: \
419 if (!multi_stack) { \
420 if (file_matches_list(elf->filename, qa_execstack)) \
421 return NULL; \
422 *found_phdr = 1; \
423 shown = 1; \
424 memcpy(ret, "!WX", 3); \
425 } \
426 } \
427 }
428 SHOW_PHDR(32)
429 SHOW_PHDR(64)
430
431 if (be_wewy_wewy_quiet || (be_quiet && !shown))
432 return NULL;
433 else
434 return ret;
435 }
436
437 /*
438 * See if this ELF contains a DT_TEXTREL tag in any of its
439 * PT_DYNAMIC sections.
440 */
441 static const char *scanelf_file_textrel(elfobj *elf, char *found_textrel)
442 {
443 static const char *ret = "TEXTREL";
444 unsigned long i;
445
446 if (!show_textrel && !show_textrels) return NULL;
447
448 if (file_matches_list(elf->filename, qa_textrels)) return NULL;
449
450 if (elf->phdr) {
451 #define SHOW_TEXTREL(B) \
452 if (elf->elf_class == ELFCLASS ## B) { \
453 Elf ## B ## _Dyn *dyn; \
454 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
455 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
456 Elf ## B ## _Off offset; \
457 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
458 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) continue; \
459 offset = EGET(phdr[i].p_offset); \
460 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
461 dyn = DYN ## B (elf->vdata + offset); \
462 while (EGET(dyn->d_tag) != DT_NULL) { \
463 if (EGET(dyn->d_tag) == DT_TEXTREL) { /*dyn->d_tag != DT_FLAGS)*/ \
464 *found_textrel = 1; \
465 /*if (dyn->d_un.d_val & DF_TEXTREL)*/ \
466 return (be_wewy_wewy_quiet ? NULL : ret); \
467 } \
468 ++dyn; \
469 } \
470 } }
471 SHOW_TEXTREL(32)
472 SHOW_TEXTREL(64)
473 }
474
475 if (be_quiet || be_wewy_wewy_quiet)
476 return NULL;
477 else
478 return " - ";
479 }
480
481 /*
482 * Scan the .text section to see if there are any relocations in it.
483 * Should rewrite this to check PT_LOAD sections that are marked
484 * Executable rather than the section named '.text'.
485 */
486 static char *scanelf_file_textrels(elfobj *elf, char *found_textrels, char *found_textrel)
487 {
488 unsigned long s, r, rmax;
489 void *symtab_void, *strtab_void, *text_void;
490
491 if (!show_textrels) return NULL;
492
493 /* don't search for TEXTREL's if the ELF doesn't have any */
494 if (!*found_textrel) scanelf_file_textrel(elf, found_textrel);
495 if (!*found_textrel) return NULL;
496
497 scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
498 text_void = elf_findsecbyname(elf, ".text");
499
500 if (symtab_void && strtab_void && text_void && elf->shdr) {
501 #define SHOW_TEXTRELS(B) \
502 if (elf->elf_class == ELFCLASS ## B) { \
503 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
504 Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \
505 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
506 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
507 Elf ## B ## _Shdr *text = SHDR ## B (text_void); \
508 Elf ## B ## _Addr vaddr = EGET(text->sh_addr); \
509 uint ## B ## _t memsz = EGET(text->sh_size); \
510 Elf ## B ## _Rel *rel; \
511 Elf ## B ## _Rela *rela; \
512 /* search the section headers for relocations */ \
513 for (s = 0; s < EGET(ehdr->e_shnum); ++s) { \
514 uint32_t sh_type = EGET(shdr[s].sh_type); \
515 if (sh_type == SHT_REL) { \
516 rel = REL ## B (elf->vdata + EGET(shdr[s].sh_offset)); \
517 rela = NULL; \
518 rmax = EGET(shdr[s].sh_size) / sizeof(*rel); \
519 } else if (sh_type == SHT_RELA) { \
520 rel = NULL; \
521 rela = RELA ## B (elf->vdata + EGET(shdr[s].sh_offset)); \
522 rmax = EGET(shdr[s].sh_size) / sizeof(*rela); \
523 } else \
524 continue; \
525 /* now see if any of the relocs are in the .text */ \
526 for (r = 0; r < rmax; ++r) { \
527 unsigned long sym_max; \
528 Elf ## B ## _Addr offset_tmp; \
529 Elf ## B ## _Sym *func; \
530 Elf ## B ## _Sym *sym; \
531 Elf ## B ## _Addr r_offset; \
532 uint ## B ## _t r_info; \
533 if (sh_type == SHT_REL) { \
534 r_offset = EGET(rel[r].r_offset); \
535 r_info = EGET(rel[r].r_info); \
536 } else { \
537 r_offset = EGET(rela[r].r_offset); \
538 r_info = EGET(rela[r].r_info); \
539 } \
540 /* make sure this relocation is inside of the .text */ \
541 if (r_offset < vaddr || r_offset >= vaddr + memsz) { \
542 if (be_verbose <= 2) continue; \
543 } else \
544 *found_textrels = 1; \
545 /* locate this relocation symbol name */ \
546 sym = SYM ## B (elf->vdata + EGET(symtab->sh_offset)); \
547 if ((void*)sym > elf->data_end) { \
548 warn("%s: corrupt ELF symbol", elf->filename); \
549 continue; \
550 } \
551 sym_max = ELF ## B ## _R_SYM(r_info); \
552 if (sym_max * EGET(symtab->sh_entsize) < symtab->sh_size) \
553 sym += sym_max; \
554 else \
555 sym = NULL; \
556 sym_max = EGET(symtab->sh_size) / EGET(symtab->sh_entsize); \
557 /* show the raw details about this reloc */ \
558 printf(" %s: ", elf->base_filename); \
559 if (sym && sym->st_name) \
560 printf("%s", elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name)); \
561 else \
562 printf("(memory/data?)"); \
563 printf(" [0x%lX]", (unsigned long)r_offset); \
564 /* now try to find the closest symbol that this rel is probably in */ \
565 sym = SYM ## B (elf->vdata + EGET(symtab->sh_offset)); \
566 func = NULL; \
567 offset_tmp = 0; \
568 while (sym_max--) { \
569 if (EGET(sym->st_value) < r_offset && EGET(sym->st_value) > offset_tmp) { \
570 func = sym; \
571 offset_tmp = EGET(sym->st_value); \
572 } \
573 ++sym; \
574 } \
575 printf(" in "); \
576 if (func && func->st_name) { \
577 const char *func_name = elf->data + EGET(strtab->sh_offset) + EGET(func->st_name); \
578 if (r_offset > EGET(func->st_size)) \
579 printf("(optimized out: previous %s)", func_name); \
580 else \
581 printf("%s", func_name); \
582 } else \
583 printf("(optimized out)"); \
584 printf(" [0x%lX]\n", (unsigned long)offset_tmp); \
585 if (be_verbose && has_objdump) { \
586 Elf ## B ## _Addr end_addr = offset_tmp + EGET(func->st_size); \
587 char *sysbuf; \
588 size_t syslen; \
589 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"; \
590 syslen = sizeof(sysfmt) + strlen(elf->filename) + 3 * sizeof(unsigned long) + 1; \
591 sysbuf = xmalloc(syslen); \
592 if (end_addr < r_offset) \
593 /* not uncommon when things are optimized out */ \
594 end_addr = r_offset + 0x100; \
595 snprintf(sysbuf, syslen, sysfmt, \
596 (unsigned long)offset_tmp, \
597 (unsigned long)end_addr, \
598 elf->filename, \
599 (unsigned long)r_offset); \
600 fflush(stdout); \
601 if (system(sysbuf)) /* don't care */; \
602 fflush(stdout); \
603 free(sysbuf); \
604 } \
605 } \
606 } }
607 SHOW_TEXTRELS(32)
608 SHOW_TEXTRELS(64)
609 }
610 if (!*found_textrels)
611 warnf("ELF %s has TEXTREL markings but doesnt appear to have any real TEXTREL's !?", elf->filename);
612
613 return NULL;
614 }
615
616 static void rpath_security_checks(elfobj *elf, char *item, const char *dt_type)
617 {
618 struct stat st;
619 switch (*item) {
620 case '/': break;
621 case '.':
622 warnf("Security problem with relative %s '%s' in %s", dt_type, item, elf->filename);
623 break;
624 case ':':
625 case '\0':
626 warnf("Security problem NULL %s in %s", dt_type, elf->filename);
627 break;
628 case '$':
629 if (fstat(elf->fd, &st) != -1)
630 if ((st.st_mode & S_ISUID) || (st.st_mode & S_ISGID))
631 warnf("Security problem with %s='%s' in %s with mode set of %o",
632 dt_type, item, elf->filename, (unsigned int) st.st_mode & 07777);
633 break;
634 default:
635 warnf("Maybe? sec problem with %s='%s' in %s", dt_type, item, elf->filename);
636 break;
637 }
638 }
639 static void scanelf_file_rpath(elfobj *elf, char *found_rpath, char **ret, size_t *ret_len)
640 {
641 unsigned long i;
642 char *rpath, *runpath, **r;
643 void *strtbl_void;
644
645 if (!show_rpath) return;
646
647 strtbl_void = elf_findsecbyname(elf, ".dynstr");
648 rpath = runpath = NULL;
649
650 if (elf->phdr && strtbl_void) {
651 #define SHOW_RPATH(B) \
652 if (elf->elf_class == ELFCLASS ## B) { \
653 Elf ## B ## _Dyn *dyn; \
654 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
655 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
656 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
657 Elf ## B ## _Off offset; \
658 Elf ## B ## _Xword word; \
659 /* Scan all the program headers */ \
660 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
661 /* Just scan dynamic headers */ \
662 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) continue; \
663 offset = EGET(phdr[i].p_offset); \
664 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
665 /* Just scan dynamic RPATH/RUNPATH headers */ \
666 dyn = DYN ## B (elf->vdata + offset); \
667 while ((word=EGET(dyn->d_tag)) != DT_NULL) { \
668 if (word == DT_RPATH) { \
669 r = &rpath; \
670 } else if (word == DT_RUNPATH) { \
671 r = &runpath; \
672 } else { \
673 ++dyn; \
674 continue; \
675 } \
676 /* Verify the memory is somewhat sane */ \
677 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
678 if (offset < (Elf ## B ## _Off)elf->len) { \
679 if (*r) warn("ELF has multiple %s's !?", get_elfdtype(word)); \
680 *r = elf->data + offset; \
681 /* cache the length in case we need to nuke this section later on */ \
682 if (fix_elf) \
683 offset = strlen(*r); \
684 /* If quiet, don't output paths in ld.so.conf */ \
685 if (be_quiet) { \
686 size_t len; \
687 char *start, *end; \
688 /* note that we only 'chop' off leading known paths. */ \
689 /* since *r is read-only memory, we can only move the ptr forward. */ \
690 start = *r; \
691 /* scan each path in : delimited list */ \
692 while (start) { \
693 rpath_security_checks(elf, start, get_elfdtype(word)); \
694 end = strchr(start, ':'); \
695 len = (end ? abs(end - start) : strlen(start)); \
696 if (use_ldcache) { \
697 size_t n; \
698 const char *ldpath; \
699 array_for_each(ldpaths, n, ldpath) \
700 if (!strncmp(ldpath, start, len) && !ldpath[len]) { \
701 *r = end; \
702 /* corner case ... if RPATH reads "/usr/lib:", we want \
703 * to show ':' rather than '' */ \
704 if (end && end[1] != '\0') \
705 (*r)++; \
706 break; \
707 } \
708 } \
709 if (!*r || !end) \
710 break; \
711 else \
712 start = start + len + 1; \
713 } \
714 } \
715 if (*r) { \
716 if (fix_elf > 2 || (fix_elf && **r == '\0')) { \
717 /* just nuke it */ \
718 nuke_it##B: \
719 memset(*r, 0x00, offset); \
720 *r = NULL; \
721 ESET(dyn->d_tag, DT_DEBUG); \
722 ESET(dyn->d_un.d_ptr, 0); \
723 } else if (fix_elf) { \
724 /* try to clean "bad" paths */ \
725 size_t len, tmpdir_len; \
726 char *start, *end; \
727 const char *tmpdir; \
728 start = *r; \
729 tmpdir = (getenv("TMPDIR") ? : "."); \
730 tmpdir_len = strlen(tmpdir); \
731 while (1) { \
732 end = strchr(start, ':'); \
733 if (start == end) { \
734 eat_this_path##B: \
735 len = strlen(end); \
736 memmove(start, end+1, len); \
737 start[len-1] = '\0'; \
738 end = start - 1; \
739 } else if (tmpdir && !strncmp(start, tmpdir, tmpdir_len)) { \
740 if (!end) { \
741 if (start == *r) \
742 goto nuke_it##B; \
743 *--start = '\0'; \
744 } else \
745 goto eat_this_path##B; \
746 } \
747 if (!end) \
748 break; \
749 start = end + 1; \
750 } \
751 if (**r == '\0') \
752 goto nuke_it##B; \
753 } \
754 if (*r) \
755 *found_rpath = 1; \
756 } \
757 } \
758 ++dyn; \
759 } \
760 } }
761 SHOW_RPATH(32)
762 SHOW_RPATH(64)
763 }
764
765 if (be_wewy_wewy_quiet) return;
766
767 if (rpath && runpath) {
768 if (!strcmp(rpath, runpath)) {
769 xstrcat(ret, runpath, ret_len);
770 } else {
771 fprintf(stderr, "RPATH [%s] != RUNPATH [%s]\n", rpath, runpath);
772 xchrcat(ret, '{', ret_len);
773 xstrcat(ret, rpath, ret_len);
774 xchrcat(ret, ',', ret_len);
775 xstrcat(ret, runpath, ret_len);
776 xchrcat(ret, '}', ret_len);
777 }
778 } else if (rpath || runpath)
779 xstrcat(ret, (runpath ? runpath : rpath), ret_len);
780 else if (!be_quiet)
781 xstrcat(ret, " - ", ret_len);
782 }
783
784 #define LDSO_CACHE_MAGIC "ld.so-"
785 #define LDSO_CACHE_MAGIC_LEN (sizeof LDSO_CACHE_MAGIC -1)
786 #define LDSO_CACHE_VER "1.7.0"
787 #define LDSO_CACHE_VER_LEN (sizeof LDSO_CACHE_VER -1)
788 #define FLAG_ANY -1
789 #define FLAG_TYPE_MASK 0x00ff
790 #define FLAG_LIBC4 0x0000
791 #define FLAG_ELF 0x0001
792 #define FLAG_ELF_LIBC5 0x0002
793 #define FLAG_ELF_LIBC6 0x0003
794 #define FLAG_REQUIRED_MASK 0xff00
795 #define FLAG_SPARC_LIB64 0x0100
796 #define FLAG_IA64_LIB64 0x0200
797 #define FLAG_X8664_LIB64 0x0300
798 #define FLAG_S390_LIB64 0x0400
799 #define FLAG_POWERPC_LIB64 0x0500
800 #define FLAG_MIPS64_LIBN32 0x0600
801 #define FLAG_MIPS64_LIBN64 0x0700
802
803 #if defined(__GLIBC__) || defined(__UCLIBC__)
804
805 static char *lookup_cache_lib(elfobj *elf, const char *fname)
806 {
807 int fd;
808 char *strs;
809 static char buf[__PAX_UTILS_PATH_MAX] = "";
810 const char *cachefile = root_rel_path("/etc/ld.so.cache");
811 struct stat st;
812
813 typedef struct {
814 char magic[LDSO_CACHE_MAGIC_LEN];
815 char version[LDSO_CACHE_VER_LEN];
816 int nlibs;
817 } header_t;
818 header_t *header;
819
820 typedef struct {
821 int flags;
822 int sooffset;
823 int liboffset;
824 } libentry_t;
825 libentry_t *libent;
826
827 if (fname == NULL)
828 return NULL;
829
830 if (ldcache == NULL) {
831 if (fstatat(root_fd, cachefile, &st, 0))
832 return NULL;
833
834 fd = openat(root_fd, cachefile, O_RDONLY);
835 if (fd == -1)
836 return NULL;
837
838 /* cache these values so we only map/unmap the cache file once */
839 ldcache_size = st.st_size;
840 header = ldcache = mmap(0, ldcache_size, PROT_READ, MAP_SHARED, fd, 0);
841 close(fd);
842
843 if (ldcache == MAP_FAILED) {
844 ldcache = NULL;
845 return NULL;
846 }
847
848 if (memcmp(header->magic, LDSO_CACHE_MAGIC, LDSO_CACHE_MAGIC_LEN) ||
849 memcmp(header->version, LDSO_CACHE_VER, LDSO_CACHE_VER_LEN))
850 {
851 munmap(ldcache, ldcache_size);
852 ldcache = NULL;
853 return NULL;
854 }
855 } else
856 header = ldcache;
857
858 libent = ldcache + sizeof(header_t);
859 strs = (char *) &libent[header->nlibs];
860
861 for (fd = 0; fd < header->nlibs; ++fd) {
862 /* This should be more fine grained, but for now we assume that
863 * diff arches will not be cached together, and we ignore the
864 * the different multilib mips cases.
865 */
866 if (elf->elf_class == ELFCLASS64 && !(libent[fd].flags & FLAG_REQUIRED_MASK))
867 continue;
868 if (elf->elf_class == ELFCLASS32 && (libent[fd].flags & FLAG_REQUIRED_MASK))
869 continue;
870
871 if (strcmp(fname, strs + libent[fd].sooffset) != 0)
872 continue;
873
874 /* Return first hit because that is how the ldso rolls */
875 strncpy(buf, strs + libent[fd].liboffset, sizeof(buf));
876 break;
877 }
878
879 return buf;
880 }
881
882 #elif defined(__NetBSD__)
883 static char *lookup_cache_lib(elfobj *elf, const char *fname)
884 {
885 static char buf[__PAX_UTILS_PATH_MAX] = "";
886 static struct stat st;
887 size_t n;
888 char *ldpath;
889
890 array_for_each(ldpath, n, ldpath) {
891 if ((unsigned) snprintf(buf, sizeof(buf), "%s/%s", ldpath, fname) >= sizeof(buf))
892 continue; /* if the pathname is too long, or something went wrong, ignore */
893
894 if (stat(buf, &st) != 0)
895 continue; /* if the lib doesn't exist in *ldpath, look further */
896
897 /* NetBSD doesn't actually do sanity checks, it just loads the file
898 * and if that doesn't work, continues looking in other directories.
899 * This cannot easily be safely emulated, unfortunately. For now,
900 * just assume that if it exists, it's a valid library. */
901
902 return buf;
903 }
904
905 /* not found in any path */
906 return NULL;
907 }
908 #else
909 #ifdef __ELF__
910 #warning Cache support not implemented for your target
911 #endif
912 static char *lookup_cache_lib(elfobj *elf, const char *fname)
913 {
914 return NULL;
915 }
916 #endif
917
918 static char *lookup_config_lib(elfobj *elf, char *fname)
919 {
920 static char buf[__PAX_UTILS_PATH_MAX] = "";
921 const char *ldpath;
922 size_t n;
923
924 array_for_each(ldpaths, n, ldpath) {
925 snprintf(buf, sizeof(buf), "%s/%s", root_rel_path(ldpath), fname);
926 if (faccessat(root_fd, buf, F_OK, AT_SYMLINK_NOFOLLOW) == 0)
927 return buf;
928 }
929
930 return NULL;
931 }
932
933 static const char *scanelf_file_needed_lib(elfobj *elf, char *found_needed, char *found_lib, int op, char **ret, size_t *ret_len)
934 {
935 unsigned long i;
936 char *needed;
937 void *strtbl_void;
938 char *p;
939
940 /*
941 * -n -> op==0 -> print all
942 * -N -> op==1 -> print requested
943 */
944 if ((op == 0 && !show_needed) || (op == 1 && !find_lib))
945 return NULL;
946
947 strtbl_void = elf_findsecbyname(elf, ".dynstr");
948
949 if (elf->phdr && strtbl_void) {
950 #define SHOW_NEEDED(B) \
951 if (elf->elf_class == ELFCLASS ## B) { \
952 Elf ## B ## _Dyn *dyn; \
953 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
954 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
955 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
956 Elf ## B ## _Off offset; \
957 size_t matched = 0; \
958 /* Walk all the program headers to find the PT_DYNAMIC */ \
959 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
960 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) \
961 continue; \
962 offset = EGET(phdr[i].p_offset); \
963 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) \
964 continue; \
965 /* Walk all the dynamic tags to find NEEDED entries */ \
966 dyn = DYN ## B (elf->vdata + offset); \
967 while (EGET(dyn->d_tag) != DT_NULL) { \
968 if (EGET(dyn->d_tag) == DT_NEEDED) { \
969 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
970 if (offset >= (Elf ## B ## _Off)elf->len) { \
971 ++dyn; \
972 continue; \
973 } \
974 needed = elf->data + offset; \
975 if (op == 0) { \
976 /* -n -> print all entries */ \
977 if (!be_wewy_wewy_quiet) { \
978 if (*found_needed) xchrcat(ret, ',', ret_len); \
979 if (use_ldpath) { \
980 if ((p = lookup_config_lib(elf, needed)) != NULL) \
981 needed = p; \
982 } else if (use_ldcache) { \
983 if ((p = lookup_cache_lib(elf, needed)) != NULL) \
984 needed = p; \
985 } \
986 xstrcat(ret, needed, ret_len); \
987 } \
988 *found_needed = 1; \
989 } else { \
990 /* -N -> print matching entries */ \
991 size_t n; \
992 const char *find_lib_name; \
993 \
994 array_for_each(find_lib_arr, n, find_lib_name) { \
995 int invert = 1; \
996 if (find_lib_name[0] == '!') \
997 invert = 0, ++find_lib_name; \
998 if (!strcmp(find_lib_name, needed) == invert) \
999 ++matched; \
1000 } \
1001 \
1002 if (matched == array_cnt(find_lib_arr)) { \
1003 *found_lib = 1; \
1004 return (be_wewy_wewy_quiet ? NULL : find_lib); \
1005 } \
1006 } \
1007 } \
1008 ++dyn; \
1009 } \
1010 } }
1011 SHOW_NEEDED(32)
1012 SHOW_NEEDED(64)
1013 if (op == 0 && !*found_needed && be_verbose)
1014 warn("ELF lacks DT_NEEDED sections: %s", elf->filename);
1015 }
1016
1017 return NULL;
1018 }
1019 static char *scanelf_file_interp(elfobj *elf, char *found_interp)
1020 {
1021 void *strtbl_void;
1022
1023 if (!show_interp) return NULL;
1024
1025 strtbl_void = elf_findsecbyname(elf, ".interp");
1026
1027 if (strtbl_void) {
1028 #define SHOW_INTERP(B) \
1029 if (elf->elf_class == ELFCLASS ## B) { \
1030 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
1031 *found_interp = 1; \
1032 return (be_wewy_wewy_quiet ? NULL : elf->data + EGET(strtbl->sh_offset)); \
1033 }
1034 SHOW_INTERP(32)
1035 SHOW_INTERP(64)
1036 }
1037 return NULL;
1038 }
1039 static char *scanelf_file_bind(elfobj *elf, char *found_bind)
1040 {
1041 unsigned long i;
1042 struct stat s;
1043 char dynamic = 0;
1044
1045 if (!show_bind) return NULL;
1046 if (!elf->phdr) return NULL;
1047
1048 #define SHOW_BIND(B) \
1049 if (elf->elf_class == ELFCLASS ## B) { \
1050 Elf ## B ## _Dyn *dyn; \
1051 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
1052 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
1053 Elf ## B ## _Off offset; \
1054 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
1055 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) continue; \
1056 dynamic = 1; \
1057 offset = EGET(phdr[i].p_offset); \
1058 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
1059 dyn = DYN ## B (elf->vdata + offset); \
1060 while (EGET(dyn->d_tag) != DT_NULL) { \
1061 if (EGET(dyn->d_tag) == DT_BIND_NOW || \
1062 (EGET(dyn->d_tag) == DT_FLAGS && EGET(dyn->d_un.d_val) & DF_BIND_NOW)) \
1063 { \
1064 if (be_quiet) return NULL; \
1065 *found_bind = 1; \
1066 return (char *)(be_wewy_wewy_quiet ? NULL : "NOW"); \
1067 } \
1068 ++dyn; \
1069 } \
1070 } \
1071 }
1072 SHOW_BIND(32)
1073 SHOW_BIND(64)
1074
1075 if (be_wewy_wewy_quiet) return NULL;
1076
1077 /* don't output anything if quiet mode and the ELF is static or not setuid */
1078 if (be_quiet && (!dynamic || (!fstat(elf->fd, &s) && !(s.st_mode & (S_ISUID|S_ISGID))))) {
1079 return NULL;
1080 } else {
1081 *found_bind = 1;
1082 return (char *)(dynamic ? "LAZY" : "STATIC");
1083 }
1084 }
1085 static char *scanelf_file_soname(elfobj *elf, char *found_soname)
1086 {
1087 unsigned long i;
1088 char *soname;
1089 void *strtbl_void;
1090
1091 if (!show_soname) return NULL;
1092
1093 strtbl_void = elf_findsecbyname(elf, ".dynstr");
1094
1095 if (elf->phdr && strtbl_void) {
1096 #define SHOW_SONAME(B) \
1097 if (elf->elf_class == ELFCLASS ## B) { \
1098 Elf ## B ## _Dyn *dyn; \
1099 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
1100 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
1101 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
1102 Elf ## B ## _Off offset; \
1103 /* only look for soname in shared objects */ \
1104 if (EGET(ehdr->e_type) != ET_DYN) \
1105 return NULL; \
1106 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
1107 if (EGET(phdr[i].p_type) != PT_DYNAMIC || EGET(phdr[i].p_filesz) == 0) continue; \
1108 offset = EGET(phdr[i].p_offset); \
1109 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
1110 dyn = DYN ## B (elf->vdata + offset); \
1111 while (EGET(dyn->d_tag) != DT_NULL) { \
1112 if (EGET(dyn->d_tag) == DT_SONAME) { \
1113 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
1114 if (offset >= (Elf ## B ## _Off)elf->len) { \
1115 ++dyn; \
1116 continue; \
1117 } \
1118 soname = elf->data + offset; \
1119 *found_soname = 1; \
1120 return (be_wewy_wewy_quiet ? NULL : soname); \
1121 } \
1122 ++dyn; \
1123 } \
1124 } }
1125 SHOW_SONAME(32)
1126 SHOW_SONAME(64)
1127 }
1128
1129 return NULL;
1130 }
1131
1132 /*
1133 * We support the symbol form:
1134 * [%[modifiers]%][[+-]<symbol name>][,[.....]]
1135 * If the symbol name is empty, then all symbols are matched.
1136 * If the symbol name is a glob ("*"), then all symbols are dumped (debug).
1137 * Do not rely on this output format at all.
1138 * Otherwise the symbol name is used to search (either regex or string compare).
1139 * If the first char of the symbol name is a plus ("+"), then only match
1140 * defined symbols. If it's a minus ("-"), only match undefined symbols.
1141 * Putting modifiers in between the percent signs allows for more in depth
1142 * filters. There are groups of modifiers. If you don't specify a member
1143 * of a group, then all types in that group are matched. The current
1144 * groups and their types are:
1145 * STT group: STT_NOTYPE:n STT_OBJECT:o STT_FUNC:f STT_FILE:F
1146 * STB group: STB_LOCAL:l STB_GLOBAL:g STB_WEAK:w
1147 * SHN group: SHN_UNDEF:u SHN_ABS:a SHN_COMMON:c {defined}:d
1148 * The "defined" value in the SHN group does not correspond to a SHN_xxx define.
1149 * You can search for multiple symbols at once by seperating with a comma (",").
1150 *
1151 * Some examples:
1152 * ELFs with a weak function "foo":
1153 * scanelf -s %wf%foo <ELFs>
1154 * ELFs that define the symbol "main":
1155 * scanelf -s +main <ELFs>
1156 * scanelf -s %d%main <ELFs>
1157 * ELFs that refer to the undefined symbol "brk":
1158 * scanelf -s -brk <ELFs>
1159 * scanelf -s %u%brk <ELFs>
1160 * All global defined objects in an ELF:
1161 * scanelf -s %ogd% <ELF>
1162 */
1163 static void
1164 scanelf_match_symname(elfobj *elf, char *found_sym, char **ret, size_t *ret_len, const char *symname,
1165 unsigned int stt, unsigned int stb, unsigned int shn, unsigned long size)
1166 {
1167 char *this_sym, *next_sym, saved = saved;
1168
1169 /* allow the user to specify a comma delimited list of symbols to search for */
1170 next_sym = NULL;
1171 do {
1172 bool inc_notype, inc_object, inc_func, inc_file,
1173 inc_local, inc_global, inc_weak,
1174 inc_def, inc_undef, inc_abs, inc_common;
1175
1176 if (next_sym) {
1177 next_sym[-1] = saved;
1178 this_sym = next_sym;
1179 } else
1180 this_sym = find_sym;
1181 if ((next_sym = strchr(this_sym, ','))) {
1182 /* make parsing easier by killing the comma temporarily */
1183 saved = *next_sym;
1184 *next_sym = '\0';
1185 next_sym += 1;
1186 }
1187
1188 /* symbol selection! */
1189 inc_notype = inc_object = inc_func = inc_file = \
1190 inc_local = inc_global = inc_weak = \
1191 inc_def = inc_undef = inc_abs = inc_common = \
1192 (*this_sym != '%');
1193
1194 /* parse the contents of %...% */
1195 if (!inc_notype) {
1196 while (*(this_sym++)) {
1197 if (*this_sym == '%') {
1198 ++this_sym;
1199 break;
1200 }
1201 switch (*this_sym) {
1202 case 'n': inc_notype = true; break;
1203 case 'o': inc_object = true; break;
1204 case 'f': inc_func = true; break;
1205 case 'F': inc_file = true; break;
1206 case 'l': inc_local = true; break;
1207 case 'g': inc_global = true; break;
1208 case 'w': inc_weak = true; break;
1209 case 'd': inc_def = true; break;
1210 case 'u': inc_undef = true; break;
1211 case 'a': inc_abs = true; break;
1212 case 'c': inc_common = true; break;
1213 default: err("invalid symbol selector '%c'", *this_sym);
1214 }
1215 }
1216
1217 /* If no types are matched, not match all */
1218 if (!inc_notype && !inc_object && !inc_func && !inc_file)
1219 inc_notype = inc_object = inc_func = inc_file = true;
1220 if (!inc_local && !inc_global && !inc_weak)
1221 inc_local = inc_global = inc_weak = true;
1222 if (!inc_def && !inc_undef && !inc_abs && !inc_common)
1223 inc_def = inc_undef = inc_abs = inc_common = true;
1224
1225 /* backwards compat for defined/undefined short hand */
1226 } else if (*this_sym == '+') {
1227 inc_undef = false;
1228 ++this_sym;
1229 } else if (*this_sym == '-') {
1230 inc_def = inc_abs = inc_common = false;
1231 ++this_sym;
1232 }
1233
1234 /* filter symbols */
1235 if ((!inc_notype && stt == STT_NOTYPE) || \
1236 (!inc_object && stt == STT_OBJECT) || \
1237 (!inc_func && stt == STT_FUNC ) || \
1238 (!inc_file && stt == STT_FILE ) || \
1239 (!inc_local && stb == STB_LOCAL ) || \
1240 (!inc_global && stb == STB_GLOBAL) || \
1241 (!inc_weak && stb == STB_WEAK ) || \
1242 (!inc_def && shn && shn < SHN_LORESERVE) || \
1243 (!inc_undef && shn == SHN_UNDEF ) || \
1244 (!inc_abs && shn == SHN_ABS ) || \
1245 (!inc_common && shn == SHN_COMMON))
1246 continue;
1247
1248 if (*this_sym == '*') {
1249 /* a "*" symbol gets you debug output */
1250 printf("%s(%s) %5lX %15s %15s %15s %s\n",
1251 ((*found_sym == 0) ? "\n\t" : "\t"),
1252 elf->base_filename,
1253 size,
1254 get_elfstttype(stt),
1255 get_elfstbtype(stb),
1256 get_elfshntype(shn),
1257 symname);
1258 goto matched;
1259
1260 } else {
1261 if (g_match) {
1262 /* regex match the symbol */
1263 if (rematch(this_sym, symname, REG_EXTENDED) != 0)
1264 continue;
1265
1266 } else if (*this_sym) {
1267 /* give empty symbols a "pass", else do a normal compare */
1268 const size_t len = strlen(this_sym);
1269 if (!(strncmp(this_sym, symname, len) == 0 &&
1270 /* Accept unversioned symbol names */
1271 (symname[len] == '\0' || symname[len] == '@')))
1272 continue;
1273 }
1274
1275 if (be_semi_verbose) {
1276 char buf[1024];
1277 snprintf(buf, sizeof(buf), "%lX %s %s",
1278 size,
1279 get_elfstttype(stt),
1280 this_sym);
1281 *ret = xstrdup(buf);
1282 } else {
1283 if (*ret) xchrcat(ret, ',', ret_len);
1284 xstrcat(ret, symname, ret_len);
1285 }
1286
1287 goto matched;
1288 }
1289 } while (next_sym);
1290
1291 return;
1292
1293 matched:
1294 *found_sym = 1;
1295 if (next_sym)
1296 next_sym[-1] = saved;
1297 }
1298
1299 static const char *scanelf_file_sym(elfobj *elf, char *found_sym)
1300 {
1301 char *ret;
1302 void *symtab_void, *strtab_void;
1303
1304 if (!find_sym) return NULL;
1305 ret = NULL;
1306
1307 scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
1308
1309 if (symtab_void && strtab_void) {
1310 #define FIND_SYM(B) \
1311 if (elf->elf_class == ELFCLASS ## B) { \
1312 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
1313 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
1314 Elf ## B ## _Sym *sym = SYM ## B (elf->vdata + EGET(symtab->sh_offset)); \
1315 Elf ## B ## _Word i, cnt = EGET(symtab->sh_entsize); \
1316 char *symname; \
1317 size_t ret_len = 0; \
1318 if (cnt) \
1319 cnt = EGET(symtab->sh_size) / cnt; \
1320 for (i = 0; i < cnt; ++i) { \
1321 if ((void*)sym > elf->data_end) { \
1322 warnf("%s: corrupt ELF symbols - aborting", elf->filename); \
1323 goto break_out; \
1324 } \
1325 if (sym->st_name) { \
1326 /* make sure the symbol name is in acceptable memory range */ \
1327 symname = elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name); \
1328 if ((void*)symname > elf->data_end) { \
1329 warnf("%s: corrupt ELF symbols", elf->filename); \
1330 ++sym; \
1331 continue; \
1332 } \
1333 scanelf_match_symname(elf, found_sym, \
1334 &ret, &ret_len, symname, \
1335 ELF##B##_ST_TYPE(EGET(sym->st_info)), \
1336 ELF##B##_ST_BIND(EGET(sym->st_info)), \
1337 EGET(sym->st_shndx), \
1338 /* st_size can be 64bit, but no one is really that big, so screw em */ \
1339 EGET(sym->st_size)); \
1340 } \
1341 ++sym; \
1342 } \
1343 }
1344 FIND_SYM(32)
1345 FIND_SYM(64)
1346 }
1347
1348 break_out:
1349 if (be_wewy_wewy_quiet) return NULL;
1350
1351 if (*find_sym != '*' && *found_sym)
1352 return ret;
1353 if (be_quiet)
1354 return NULL;
1355 else
1356 return " - ";
1357 }
1358
1359 static const char *scanelf_file_sections(elfobj *elf, char *found_section)
1360 {
1361 if (!find_section)
1362 return NULL;
1363
1364 #define FIND_SECTION(B) \
1365 if (elf->elf_class == ELFCLASS ## B) { \
1366 size_t matched, n; \
1367 int invert; \
1368 const char *section_name; \
1369 Elf ## B ## _Shdr *section; \
1370 \
1371 matched = 0; \
1372 array_for_each(find_section_arr, n, section_name) { \
1373 invert = (*section_name == '!' ? 1 : 0); \
1374 section = SHDR ## B (elf_findsecbyname(elf, section_name + invert)); \
1375 if ((section == NULL && invert) || (section != NULL && !invert)) \
1376 ++matched; \
1377 } \
1378 \
1379 if (matched == array_cnt(find_section_arr)) \
1380 *found_section = 1; \
1381 }
1382 FIND_SECTION(32)
1383 FIND_SECTION(64)
1384
1385 if (be_wewy_wewy_quiet)
1386 return NULL;
1387
1388 if (*found_section)
1389 return find_section;
1390
1391 if (be_quiet)
1392 return NULL;
1393 else
1394 return " - ";
1395 }
1396
1397 /* scan an elf file and show all the fun stuff */
1398 #define prints(str) ({ ssize_t ret = write(fileno(stdout), str, strlen(str)); ret; })
1399 static int scanelf_elfobj(elfobj *elf)
1400 {
1401 unsigned long i;
1402 char found_pax, found_phdr, found_relro, found_load, found_textrel,
1403 found_rpath, found_needed, found_interp, found_bind, found_soname,
1404 found_sym, found_lib, found_file, found_textrels, found_section;
1405 static char *out_buffer = NULL;
1406 static size_t out_len;
1407
1408 found_pax = found_phdr = found_relro = found_load = found_textrel = \
1409 found_rpath = found_needed = found_interp = found_bind = found_soname = \
1410 found_sym = found_lib = found_file = found_textrels = found_section = 0;
1411
1412 if (be_verbose > 2)
1413 printf("%s: scanning file {%s,%s}\n", elf->filename,
1414 get_elfeitype(EI_CLASS, elf->elf_class),
1415 get_elfeitype(EI_DATA, elf->data[EI_DATA]));
1416 else if (be_verbose > 1)
1417 printf("%s: scanning file\n", elf->filename);
1418
1419 /* init output buffer */
1420 if (!out_buffer) {
1421 out_len = sizeof(char) * 80;
1422 out_buffer = xmalloc(out_len);
1423 }
1424 *out_buffer = '\0';
1425
1426 /* show the header */
1427 if (!be_quiet && show_banner) {
1428 for (i = 0; out_format[i]; ++i) {
1429 if (!IS_MODIFIER(out_format[i])) continue;
1430
1431 switch (out_format[++i]) {
1432 case '+': break;
1433 case '%': break;
1434 case '#': break;
1435 case 'F':
1436 case 'p':
1437 case 'f': prints("FILE "); found_file = 1; break;
1438 case 'o': prints(" TYPE "); break;
1439 case 'x': prints(" PAX "); break;
1440 case 'e': prints("STK/REL/PTL "); break;
1441 case 't': prints("TEXTREL "); break;
1442 case 'r': prints("RPATH "); break;
1443 case 'M': prints("CLASS "); break;
1444 case 'l':
1445 case 'n': prints("NEEDED "); break;
1446 case 'i': prints("INTERP "); break;
1447 case 'b': prints("BIND "); break;
1448 case 'Z': prints("SIZE "); break;
1449 case 'S': prints("SONAME "); break;
1450 case 's': prints("SYM "); break;
1451 case 'N': prints("LIB "); break;
1452 case 'T': prints("TEXTRELS "); break;
1453 case 'k': prints("SECTION "); break;
1454 case 'a': prints("ARCH "); break;
1455 case 'I': prints("OSABI "); break;
1456 case 'Y': prints("EABI "); break;
1457 case 'O': prints("PERM "); break;
1458 case 'D': prints("ENDIAN "); break;
1459 default: warnf("'%c' has no title ?", out_format[i]);
1460 }
1461 }
1462 if (!found_file) prints("FILE ");
1463 prints("\n");
1464 found_file = 0;
1465 show_banner = 0;
1466 }
1467
1468 /* dump all the good stuff */
1469 for (i = 0; out_format[i]; ++i) {
1470 const char *out;
1471 const char *tmp;
1472 static char ubuf[sizeof(unsigned long)*2];
1473 if (!IS_MODIFIER(out_format[i])) {
1474 xchrcat(&out_buffer, out_format[i], &out_len);
1475 continue;
1476 }
1477
1478 out = NULL;
1479 be_wewy_wewy_quiet = (out_format[i] == '#');
1480 be_semi_verbose = (out_format[i] == '+');
1481 switch (out_format[++i]) {
1482 case '+':
1483 case '%':
1484 case '#':
1485 xchrcat(&out_buffer, out_format[i], &out_len); break;
1486 case 'F':
1487 found_file = 1;
1488 if (be_wewy_wewy_quiet) break;
1489 xstrcat(&out_buffer, elf->filename, &out_len);
1490 break;
1491 case 'p':
1492 found_file = 1;
1493 if (be_wewy_wewy_quiet) break;
1494 tmp = elf->filename;
1495 if (search_path) {
1496 ssize_t len_search = strlen(search_path);
1497 ssize_t len_file = strlen(elf->filename);
1498 if (!strncmp(elf->filename, search_path, len_search) && \
1499 len_file > len_search)
1500 tmp += len_search;
1501 if (*tmp == '/' && search_path[len_search-1] == '/') tmp++;
1502 }
1503 xstrcat(&out_buffer, tmp, &out_len);
1504 break;
1505 case 'f':
1506 found_file = 1;
1507 if (be_wewy_wewy_quiet) break;
1508 tmp = strrchr(elf->filename, '/');
1509 tmp = (tmp == NULL ? elf->filename : tmp+1);
1510 xstrcat(&out_buffer, tmp, &out_len);
1511 break;
1512 case 'o': out = get_elfetype(elf); break;
1513 case 'x': out = scanelf_file_pax(elf, &found_pax); break;
1514 case 'e': out = scanelf_file_phdr(elf, &found_phdr, &found_relro, &found_load); break;
1515 case 't': out = scanelf_file_textrel(elf, &found_textrel); break;
1516 case 'T': out = scanelf_file_textrels(elf, &found_textrels, &found_textrel); break;
1517 case 'r': scanelf_file_rpath(elf, &found_rpath, &out_buffer, &out_len); break;
1518 case 'M': out = get_elfeitype(EI_CLASS, elf->data[EI_CLASS]); break;
1519 case 'D': out = get_endian(elf); break;
1520 case 'O': out = strfileperms(elf->filename); break;
1521 case 'n':
1522 case 'N': out = scanelf_file_needed_lib(elf, &found_needed, &found_lib, (out_format[i]=='N'), &out_buffer, &out_len); break;
1523 case 'i': out = scanelf_file_interp(elf, &found_interp); break;
1524 case 'b': out = scanelf_file_bind(elf, &found_bind); break;
1525 case 'S': out = scanelf_file_soname(elf, &found_soname); break;
1526 case 's': out = scanelf_file_sym(elf, &found_sym); break;
1527 case 'k': out = scanelf_file_sections(elf, &found_section); break;
1528 case 'a': out = get_elfemtype(elf); break;
1529 case 'I': out = get_elfosabi(elf); break;
1530 case 'Y': out = get_elf_eabi(elf); break;
1531 case 'Z': snprintf(ubuf, sizeof(ubuf), "%lu", (unsigned long)elf->len); out = ubuf; break;;
1532 default: warnf("'%c' has no scan code?", out_format[i]);
1533 }
1534 if (out)
1535 xstrcat(&out_buffer, out, &out_len);
1536 }
1537
1538 #define FOUND_SOMETHING() \
1539 (found_pax || found_phdr || found_relro || found_load || found_textrel || \
1540 found_rpath || found_needed || found_interp || found_bind || \
1541 found_soname || found_sym || found_lib || found_textrels || found_section )
1542
1543 if (!found_file && (!be_quiet || (be_quiet && FOUND_SOMETHING()))) {
1544 xchrcat(&out_buffer, ' ', &out_len);
1545 xstrcat(&out_buffer, elf->filename, &out_len);
1546 }
1547 if (!be_quiet || (be_quiet && FOUND_SOMETHING())) {
1548 puts(out_buffer);
1549 fflush(stdout);
1550 }
1551
1552 return 0;
1553 }
1554
1555 /* scan a single elf */
1556 static int scanelf_elf(const char *filename, int fd, size_t len)
1557 {
1558 int ret = 1;
1559 elfobj *elf;
1560
1561 /* verify this is real ELF */
1562 if ((elf = _readelf_fd(filename, fd, len, !fix_elf)) == NULL) {
1563 if (be_verbose > 2) printf("%s: not an ELF\n", filename);
1564 return 2;
1565 }
1566 switch (match_bits) {
1567 case 32:
1568 if (elf->elf_class != ELFCLASS32)
1569 goto label_done;
1570 break;
1571 case 64:
1572 if (elf->elf_class != ELFCLASS64)
1573 goto label_done;
1574 break;
1575 default: break;
1576 }
1577 if (match_etypes) {
1578 char sbuf[126];
1579 strncpy(sbuf, match_etypes, sizeof(sbuf));
1580 if (strchr(match_etypes, ',') != NULL) {
1581 char *p;
1582 while ((p = strrchr(sbuf, ',')) != NULL) {
1583 *p = 0;
1584 if (etype_lookup(p+1) == get_etype(elf))
1585 goto label_ret;
1586 }
1587 }
1588 if (etype_lookup(sbuf) != get_etype(elf))
1589 goto label_done;
1590 }
1591
1592 label_ret:
1593 ret = scanelf_elfobj(elf);
1594
1595 label_done:
1596 unreadelf(elf);
1597 return ret;
1598 }
1599
1600 /* scan an archive of elfs */
1601 static int scanelf_archive(const char *filename, int fd, size_t len)
1602 {
1603 archive_handle *ar;
1604 archive_member *m;
1605 char *ar_buffer;
1606 elfobj *elf;
1607
1608 ar = ar_open_fd(filename, fd);
1609 if (ar == NULL)
1610 return 1;
1611
1612 ar_buffer = mmap(0, len, PROT_READ | (fix_elf ? PROT_WRITE : 0), (fix_elf ? MAP_SHARED : MAP_PRIVATE), fd, 0);
1613 while ((m = ar_next(ar)) != NULL) {
1614 off_t cur_pos = lseek(fd, 0, SEEK_CUR);
1615 if (cur_pos == -1)
1616 errp("lseek() failed");
1617 elf = readelf_buffer(m->name, ar_buffer + cur_pos, m->size);
1618 if (elf) {
1619 scanelf_elfobj(elf);
1620 unreadelf(elf);
1621 }
1622 }
1623 munmap(ar_buffer, len);
1624
1625 return 0;
1626 }
1627 /* scan a file which may be an elf or an archive or some other magical beast */
1628 static int scanelf_fileat(int dir_fd, const char *filename, const struct stat *st_cache)
1629 {
1630 const struct stat *st = st_cache;
1631 struct stat symlink_st;
1632 int fd;
1633
1634 /* always handle regular files and handle symlinked files if no -y */
1635 if (S_ISLNK(st->st_mode)) {
1636 if (!scan_symlink)
1637 return 1;
1638 fstatat(dir_fd, filename, &symlink_st, 0);
1639 st = &symlink_st;
1640 }
1641
1642 if (!S_ISREG(st->st_mode)) {
1643 if (be_verbose > 2) printf("%s: skipping non-file\n", filename);
1644 return 1;
1645 }
1646
1647 if (match_perms) {
1648 if ((st->st_mode | match_perms) != st->st_mode)
1649 return 1;
1650 }
1651 fd = openat(dir_fd, filename, (fix_elf ? O_RDWR : O_RDONLY) | O_CLOEXEC);
1652 if (fd == -1)
1653 return 1;
1654
1655 if (scanelf_elf(filename, fd, st->st_size) == 2) {
1656 /* if it isn't an ELF, maybe it's an .a archive */
1657 if (scan_archives)
1658 scanelf_archive(filename, fd, st->st_size);
1659
1660 /*
1661 * unreadelf() implicitly closes its fd, so only close it
1662 * when we are returning it in the non-ELF case
1663 */
1664 close(fd);
1665 }
1666
1667 return 0;
1668 }
1669
1670 /* scan a directory for ET_EXEC files and print when we find one */
1671 static int scanelf_dirat(int dir_fd, const char *path)
1672 {
1673 register DIR *dir;
1674 register struct dirent *dentry;
1675 struct stat st_top, st;
1676 char buf[__PAX_UTILS_PATH_MAX], *subpath;
1677 size_t pathlen = 0, len = 0;
1678 int ret = 0;
1679 int subdir_fd;
1680
1681 /* make sure path exists */
1682 if (fstatat(dir_fd, path, &st_top, AT_SYMLINK_NOFOLLOW) == -1) {
1683 if (be_verbose > 2) printf("%s: does not exist\n", path);
1684 return 1;
1685 }
1686
1687 /* ok, if it isn't a directory, assume we can open it */
1688 if (!S_ISDIR(st_top.st_mode))
1689 return scanelf_fileat(dir_fd, path, &st_top);
1690
1691 /* now scan the dir looking for fun stuff */
1692 subdir_fd = openat(dir_fd, path, O_RDONLY|O_CLOEXEC);
1693 if (subdir_fd == -1)
1694 dir = NULL;
1695 else
1696 dir = fdopendir(subdir_fd);
1697 if (dir == NULL) {
1698 if (subdir_fd != -1)
1699 close(subdir_fd);
1700 warnfp("could not opendir(%s)", path);
1701 return 1;
1702 }
1703 if (be_verbose > 1) printf("%s: scanning dir\n", path);
1704
1705 subpath = stpcpy(buf, path);
1706 *subpath++ = '/';
1707 pathlen = subpath - buf;
1708 while ((dentry = readdir(dir))) {
1709 if (!strcmp(dentry->d_name, ".") || !strcmp(dentry->d_name, ".."))
1710 continue;
1711
1712 if (fstatat(subdir_fd, dentry->d_name, &st, AT_SYMLINK_NOFOLLOW) == -1)
1713 continue;
1714
1715 len = strlen(dentry->d_name);
1716 if (len + pathlen + 1 >= sizeof(buf)) {
1717 warnf("Skipping '%s%s': len > sizeof(buf); %zu > %zu\n",
1718 path, dentry->d_name, len + pathlen + 1, sizeof(buf));
1719 continue;
1720 }
1721 memcpy(subpath, dentry->d_name, len);
1722 subpath[len] = '\0';
1723
1724 if (S_ISREG(st.st_mode))
1725 ret = scanelf_fileat(dir_fd, buf, &st);
1726 else if (dir_recurse && S_ISDIR(st.st_mode)) {
1727 if (dir_crossmount || (st_top.st_dev == st.st_dev))
1728 ret = scanelf_dirat(dir_fd, buf);
1729 }
1730 }
1731 closedir(dir);
1732
1733 return ret;
1734 }
1735 static int scanelf_dir(const char *path)
1736 {
1737 return scanelf_dirat(root_fd, root_rel_path(path));
1738 }
1739
1740 static int scanelf_from_file(const char *filename)
1741 {
1742 FILE *fp;
1743 char *p, *path;
1744 size_t len;
1745 int ret;
1746
1747 if (strcmp(filename, "-") == 0)
1748 fp = stdin;
1749 else if ((fp = fopen(filename, "r")) == NULL)
1750 return 1;
1751
1752 path = NULL;
1753 len = 0;
1754 ret = 0;
1755 while (getline(&path, &len, fp) != -1) {
1756 if ((p = strchr(path, '\n')) != NULL)
1757 *p = 0;
1758 search_path = path;
1759 ret = scanelf_dir(path);
1760 }
1761 free(path);
1762
1763 if (fp != stdin)
1764 fclose(fp);
1765
1766 return ret;
1767 }
1768
1769 #if defined(__GLIBC__) || defined(__UCLIBC__) || defined(__NetBSD__)
1770
1771 static int _load_ld_cache_config(const char *fname)
1772 {
1773 FILE *fp = NULL;
1774 char *p, *path;
1775 size_t len;
1776 int curr_fd = -1;
1777
1778 fp = fopenat_r(root_fd, root_rel_path(fname));
1779 if (fp == NULL)
1780 return -1;
1781
1782 path = NULL;
1783 len = 0;
1784 while (getline(&path, &len, fp) != -1) {
1785 if ((p = strrchr(path, '\r')) != NULL)
1786 *p = 0;
1787 if ((p = strchr(path, '\n')) != NULL)
1788 *p = 0;
1789
1790 /* recursive includes of the same file will make this segfault. */
1791 if ((memcmp(path, "include", 7) == 0) && isblank(path[7])) {
1792 glob_t gl;
1793 size_t x;
1794 const char *gpath;
1795
1796 /* re-use existing path buffer ... need to be creative */
1797 if (path[8] != '/')
1798 gpath = memcpy(path + 3, "/etc/", 5);
1799 else
1800 gpath = path + 8;
1801 if (root_fd != AT_FDCWD) {
1802 if (curr_fd == -1) {
1803 curr_fd = open(".", O_RDONLY|O_CLOEXEC);
1804 if (fchdir(root_fd))
1805 errp("unable to change to root dir");
1806 }
1807 gpath = root_rel_path(gpath);
1808 }
1809
1810 if (glob(gpath, 0, NULL, &gl) == 0) {
1811 for (x = 0; x < gl.gl_pathc; ++x) {
1812 /* try to avoid direct loops */
1813 if (strcmp(gl.gl_pathv[x], fname) == 0)
1814 continue;
1815 _load_ld_cache_config(gl.gl_pathv[x]);
1816 }
1817 globfree(&gl);
1818 }
1819
1820 /* failed globs are ignored by glibc */
1821 continue;
1822 }
1823
1824 if (*path != '/')
1825 continue;
1826
1827 xarraypush_str(ldpaths, path);
1828 }
1829 free(path);
1830
1831 fclose(fp);
1832
1833 if (curr_fd != -1) {
1834 if (fchdir(curr_fd))
1835 /* don't care */;
1836 close(curr_fd);
1837 }
1838
1839 return 0;
1840 }
1841
1842 #elif defined(__FreeBSD__) || defined(__DragonFly__)
1843
1844 static int _load_ld_cache_config(const char *fname)
1845 {
1846 FILE *fp = NULL;
1847 char *b = NULL, *p;
1848 struct elfhints_hdr hdr;
1849
1850 fp = fopenat_r(root_fd, root_rel_path(fname));
1851 if (fp == NULL)
1852 return -1;
1853
1854 if (fread(&hdr, 1, sizeof(hdr), fp) != sizeof(hdr) ||
1855 hdr.magic != ELFHINTS_MAGIC || hdr.version != 1 ||
1856 fseek(fp, hdr.strtab + hdr.dirlist, SEEK_SET) == -1)
1857 {
1858 fclose(fp);
1859 return -1;
1860 }
1861
1862 b = xmalloc(hdr.dirlistlen + 1);
1863 if (fread(b, 1, hdr.dirlistlen+1, fp) != hdr.dirlistlen+1) {
1864 fclose(fp);
1865 free(b);
1866 return -1;
1867 }
1868
1869 while ((p = strsep(&b, ":"))) {
1870 if (*p == '\0')
1871 continue;
1872 xarraypush_str(ldpaths, p);
1873 }
1874
1875 free(b);
1876 fclose(fp);
1877 return 0;
1878 }
1879
1880 #else
1881 #ifdef __ELF__
1882 #warning Cache config support not implemented for your target
1883 #endif
1884 static int _load_ld_cache_config(const char *fname)
1885 {
1886 return 0;
1887 }
1888 #endif
1889
1890 static void load_ld_cache_config(const char *fname)
1891 {
1892 bool scan_l, scan_ul, scan_ull;
1893 size_t n;
1894 const char *ldpath;
1895
1896 _load_ld_cache_config(fname);
1897
1898 scan_l = scan_ul = scan_ull = false;
1899 if (array_cnt(ldpaths)) {
1900 array_for_each(ldpaths, n, ldpath) {
1901 if (!scan_l && !strcmp(ldpath, "/lib")) scan_l = true;
1902 if (!scan_ul && !strcmp(ldpath, "/usr/lib")) scan_ul = true;
1903 if (!scan_ull && !strcmp(ldpath, "/usr/local/lib")) scan_ull = true;
1904 }
1905 }
1906
1907 if (!scan_l) xarraypush_str(ldpaths, "/lib");
1908 if (!scan_ul) xarraypush_str(ldpaths, "/usr/lib");
1909 if (!scan_ull) xarraypush_str(ldpaths, "/usr/local/lib");
1910 }
1911
1912 /* scan /etc/ld.so.conf for paths */
1913 static void scanelf_ldpath(void)
1914 {
1915 size_t n;
1916 const char *ldpath;
1917
1918 array_for_each(ldpaths, n, ldpath)
1919 scanelf_dir(ldpath);
1920 }
1921
1922 /* scan env PATH for paths */
1923 static void scanelf_envpath(void)
1924 {
1925 char *path, *p;
1926
1927 path = getenv("PATH");
1928 if (!path)
1929 err("PATH is not set in your env !");
1930 path = xstrdup(path);
1931
1932 while ((p = strrchr(path, ':')) != NULL) {
1933 scanelf_dir(p + 1);
1934 *p = 0;
1935 }
1936
1937 free(path);
1938 }
1939
1940 /* usage / invocation handling functions */ /* Free Flags: c d j u w G H J K P Q U W */
1941 #define PARSE_FLAGS "plRmyAXz:xetrnLibSs:k:gN:TaqvF:f:o:E:M:DIYO:ZCBhV"
1942 #define a_argument required_argument
1943 static struct option const long_opts[] = {
1944 {"path", no_argument, NULL, 'p'},
1945 {"ldpath", no_argument, NULL, 'l'},
1946 {"use-ldpath",no_argument, NULL, 129},
1947 {"root", a_argument, NULL, 128},
1948 {"recursive", no_argument, NULL, 'R'},
1949 {"mount", no_argument, NULL, 'm'},
1950 {"symlink", no_argument, NULL, 'y'},
1951 {"archives", no_argument, NULL, 'A'},
1952 {"ldcache", no_argument, NULL, 'L'},
1953 {"fix", no_argument, NULL, 'X'},
1954 {"setpax", a_argument, NULL, 'z'},
1955 {"pax", no_argument, NULL, 'x'},
1956 {"header", no_argument, NULL, 'e'},
1957 {"textrel", no_argument, NULL, 't'},
1958 {"rpath", no_argument, NULL, 'r'},
1959 {"needed", no_argument, NULL, 'n'},
1960 {"interp", no_argument, NULL, 'i'},
1961 {"bind", no_argument, NULL, 'b'},
1962 {"soname", no_argument, NULL, 'S'},
1963 {"symbol", a_argument, NULL, 's'},
1964 {"section", a_argument, NULL, 'k'},
1965 {"lib", a_argument, NULL, 'N'},
1966 {"gmatch", no_argument, NULL, 'g'},
1967 {"textrels", no_argument, NULL, 'T'},
1968 {"etype", a_argument, NULL, 'E'},
1969 {"bits", a_argument, NULL, 'M'},
1970 {"endian", no_argument, NULL, 'D'},
1971 {"osabi", no_argument, NULL, 'I'},
1972 {"eabi", no_argument, NULL, 'Y'},
1973 {"perms", a_argument, NULL, 'O'},
1974 {"size", no_argument, NULL, 'Z'},
1975 {"all", no_argument, NULL, 'a'},
1976 {"quiet", no_argument, NULL, 'q'},
1977 {"verbose", no_argument, NULL, 'v'},
1978 {"format", a_argument, NULL, 'F'},
1979 {"from", a_argument, NULL, 'f'},
1980 {"file", a_argument, NULL, 'o'},
1981 {"nocolor", no_argument, NULL, 'C'},
1982 {"nobanner", no_argument, NULL, 'B'},
1983 {"help", no_argument, NULL, 'h'},
1984 {"version", no_argument, NULL, 'V'},
1985 {NULL, no_argument, NULL, 0x0}
1986 };
1987
1988 static const char * const opts_help[] = {
1989 "Scan all directories in PATH environment",
1990 "Scan all directories in /etc/ld.so.conf",
1991 "Use ld.so.conf to show full path (use with -r/-n)",
1992 "Root directory (use with -l or -p)",
1993 "Scan directories recursively",
1994 "Don't recursively cross mount points",
1995 "Don't scan symlinks",
1996 "Scan archives (.a files)",
1997 "Utilize ld.so.cache to show full path (use with -r/-n)",
1998 "Try and 'fix' bad things (use with -r/-e)",
1999 "Sets EI_PAX/PT_PAX_FLAGS to <arg> (use with -Xx)\n",
2000 "Print PaX markings",
2001 "Print GNU_STACK/PT_LOAD markings",
2002 "Print TEXTREL information",
2003 "Print RPATH information",
2004 "Print NEEDED information",
2005 "Print INTERP information",
2006 "Print BIND information",
2007 "Print SONAME information",
2008 "Find a specified symbol",
2009 "Find a specified section",
2010 "Find a specified library",
2011 "Use regex matching rather than string compare (use with -s)",
2012 "Locate cause of TEXTREL",
2013 "Print only ELF files matching etype ET_DYN,ET_EXEC ...",
2014 "Print only ELF files matching numeric bits",
2015 "Print Endianness",
2016 "Print OSABI",
2017 "Print EABI (EM_ARM Only)",
2018 "Print only ELF files matching octal permissions",
2019 "Print ELF file size",
2020 "Print all useful/simple info\n",
2021 "Only output 'bad' things",
2022 "Be verbose (can be specified more than once)",
2023 "Use specified format for output",
2024 "Read input stream from a filename",
2025 "Write output stream to a filename",
2026 "Don't emit color in output",
2027 "Don't display the header",
2028 "Print this help and exit",
2029 "Print version and exit",
2030 NULL
2031 };
2032
2033 /* display usage and exit */
2034 static void usage(int status)
2035 {
2036 unsigned long i;
2037 printf("* Scan ELF binaries for stuff\n\n"
2038 "Usage: %s [options] <dir1/file1> [dir2 dirN file2 fileN ...]\n\n", argv0);
2039 printf("Options: -[%s]\n", PARSE_FLAGS);
2040 for (i = 0; long_opts[i].name; ++i)
2041 if (long_opts[i].has_arg == no_argument)
2042 printf(" -%c, --%-14s* %s\n", long_opts[i].val,
2043 long_opts[i].name, opts_help[i]);
2044 else if (long_opts[i].val > '~')
2045 printf(" --%-7s <arg> * %s\n",
2046 long_opts[i].name, opts_help[i]);
2047 else
2048 printf(" -%c, --%-7s <arg> * %s\n", long_opts[i].val,
2049 long_opts[i].name, opts_help[i]);
2050
2051 puts("\nFor more information, see the scanelf(1) manpage");
2052 exit(status);
2053 }
2054
2055 /* parse command line arguments and preform needed actions */
2056 #define do_pax_state(option, flag) \
2057 if (islower(option)) { \
2058 flags &= ~PF_##flag; \
2059 flags |= PF_NO##flag; \
2060 } else { \
2061 flags &= ~PF_NO##flag; \
2062 flags |= PF_##flag; \
2063 }
2064 static int parseargs(int argc, char *argv[])
2065 {
2066 int i;
2067 const char *from_file = NULL;
2068 int ret = 0;
2069 char load_cache_config = 0;
2070
2071 opterr = 0;
2072 while ((i=getopt_long(argc, argv, PARSE_FLAGS, long_opts, NULL)) != -1) {
2073 switch (i) {
2074
2075 case 'V':
2076 printf("pax-utils-%s: %s compiled %s\n%s\n"
2077 "%s written for Gentoo by <solar and vapier @ gentoo.org>\n",
2078 VERSION, __FILE__, __DATE__, rcsid, argv0);
2079 exit(EXIT_SUCCESS);
2080 break;
2081 case 'h': usage(EXIT_SUCCESS); break;
2082 case 'f':
2083 if (from_file) warn("You prob don't want to specify -f twice");
2084 from_file = optarg;
2085 break;
2086 case 'E':
2087 match_etypes = optarg;
2088 break;
2089 case 'M':
2090 match_bits = atoi(optarg);
2091 if (match_bits == 0) {
2092 if (strcmp(optarg, "ELFCLASS32") == 0)
2093 match_bits = 32;
2094 if (strcmp(optarg, "ELFCLASS64") == 0)
2095 match_bits = 64;
2096 }
2097 break;
2098 case 'O':
2099 if (sscanf(optarg, "%o", &match_perms) == -1)
2100 match_bits = 0;
2101 break;
2102 case 'o': {
2103 if (freopen(optarg, "w", stdout) == NULL)
2104 errp("Could not freopen(%s)", optarg);
2105 break;
2106 }
2107 case 'k':
2108 xarraypush_str(find_section_arr, optarg);
2109 break;
2110 case 's': {
2111 if (find_sym) warn("You prob don't want to specify -s twice");
2112 find_sym = optarg;
2113 break;
2114 }
2115 case 'N':
2116 xarraypush_str(find_lib_arr, optarg);
2117 break;
2118 case 'F': {
2119 if (out_format) warn("You prob don't want to specify -F twice");
2120 out_format = optarg;
2121 break;
2122 }
2123 case 'z': {
2124 unsigned long flags = (PF_NOEMUTRAMP | PF_NORANDEXEC);
2125 size_t x;
2126
2127 for (x = 0; x < strlen(optarg); x++) {
2128 switch (optarg[x]) {
2129 case 'p':
2130 case 'P':
2131 do_pax_state(optarg[x], PAGEEXEC);
2132 break;
2133 case 's':
2134 case 'S':
2135 do_pax_state(optarg[x], SEGMEXEC);
2136 break;
2137 case 'm':
2138 case 'M':
2139 do_pax_state(optarg[x], MPROTECT);
2140 break;
2141 case 'e':
2142 case 'E':
2143 do_pax_state(optarg[x], EMUTRAMP);
2144 break;
2145 case 'r':
2146 case 'R':
2147 do_pax_state(optarg[x], RANDMMAP);
2148 break;
2149 case 'x':
2150 case 'X':
2151 do_pax_state(optarg[x], RANDEXEC);
2152 break;
2153 default:
2154 break;
2155 }
2156 }
2157 if (!(((flags & PF_PAGEEXEC) && (flags & PF_NOPAGEEXEC)) ||
2158 ((flags & PF_SEGMEXEC) && (flags & PF_NOSEGMEXEC)) ||
2159 ((flags & PF_RANDMMAP) && (flags & PF_NORANDMMAP)) ||
2160 ((flags & PF_RANDEXEC) && (flags & PF_NORANDEXEC)) ||
2161 ((flags & PF_EMUTRAMP) && (flags & PF_NOEMUTRAMP)) ||
2162 ((flags & PF_RANDMMAP) && (flags & PF_NORANDMMAP))))
2163 setpax = flags;
2164 break;
2165 }
2166 case 'Z': show_size = 1; break;
2167 case 'g': g_match = 1; break;
2168 case 'L': load_cache_config = use_ldcache = 1; break;
2169 case 'y': scan_symlink = 0; break;
2170 case 'A': scan_archives = 1; break;
2171 case 'C': color_init(true); break;
2172 case 'B': show_banner = 0; break;
2173 case 'l': load_cache_config = scan_ldpath = 1; break;
2174 case 'p': scan_envpath = 1; break;
2175 case 'R': dir_recurse = 1; break;
2176 case 'm': dir_crossmount = 0; break;
2177 case 'X': ++fix_elf; break;
2178 case 'x': show_pax = 1; break;
2179 case 'e': show_phdr = 1; break;
2180 case 't': show_textrel = 1; break;
2181 case 'r': show_rpath = 1; break;
2182 case 'n': show_needed = 1; break;
2183 case 'i': show_interp = 1; break;
2184 case 'b': show_bind = 1; break;
2185 case 'S': show_soname = 1; break;
2186 case 'T': show_textrels = 1; break;
2187 case 'q': be_quiet = 1; break;
2188 case 'v': be_verbose = (be_verbose % 20) + 1; break;
2189 case 'a': show_perms = show_pax = show_phdr = show_textrel = show_rpath = show_bind = show_endian = 1; break;
2190 case 'D': show_endian = 1; break;
2191 case 'I': show_osabi = 1; break;
2192 case 'Y': show_eabi = 1; break;
2193 case 128:
2194 root_fd = open(optarg, O_RDONLY|O_CLOEXEC);
2195 if (root_fd == -1)
2196 err("Could not open root: %s", optarg);
2197 break;
2198 case 129: load_cache_config = use_ldpath = 1; break;
2199 case ':':
2200 err("Option '%c' is missing parameter", optopt);
2201 case '?':
2202 err("Unknown option '%c' or argument missing", optopt);
2203 default:
2204 err("Unhandled option '%c'; please report this", i);
2205 }
2206 }
2207 if (show_textrels && be_verbose)
2208 has_objdump = bin_in_path("objdump");
2209 /* flatten arrays for display */
2210 if (array_cnt(find_lib_arr))
2211 find_lib = array_flatten_str(find_lib_arr);
2212 if (array_cnt(find_section_arr))
2213 find_section = array_flatten_str(find_section_arr);
2214 /* let the format option override all other options */
2215 if (out_format) {
2216 show_pax = show_phdr = show_textrel = show_rpath = \
2217 show_needed = show_interp = show_bind = show_soname = \
2218 show_textrels = show_perms = show_endian = show_size = \
2219 show_osabi = show_eabi = 0;
2220 for (i = 0; out_format[i]; ++i) {
2221 if (!IS_MODIFIER(out_format[i])) continue;
2222
2223 switch (out_format[++i]) {
2224 case '+': break;
2225 case '%': break;
2226 case '#': break;
2227 case 'F': break;
2228 case 'p': break;
2229 case 'f': break;
2230 case 'k': break;
2231 case 's': break;
2232 case 'N': break;
2233 case 'o': break;
2234 case 'a': break;
2235 case 'M': break;
2236 case 'Z': show_size = 1; break;
2237 case 'D': show_endian = 1; break;
2238 case 'I': show_osabi = 1; break;
2239 case 'Y': show_eabi = 1; break;
2240 case 'O': show_perms = 1; break;
2241 case 'x': show_pax = 1; break;
2242 case 'e': show_phdr = 1; break;
2243 case 't': show_textrel = 1; break;
2244 case 'r': show_rpath = 1; break;
2245 case 'n': show_needed = 1; break;
2246 case 'i': show_interp = 1; break;
2247 case 'b': show_bind = 1; break;
2248 case 'S': show_soname = 1; break;
2249 case 'T': show_textrels = 1; break;
2250 default:
2251 err("invalid format specifier '%c' (byte %i)",
2252 out_format[i], i+1);
2253 }
2254 }
2255
2256 /* construct our default format */
2257 } else {
2258 size_t fmt_len = 30;
2259 out_format = xmalloc(sizeof(char) * fmt_len);
2260 *out_format = '\0';
2261 if (!be_quiet) xstrcat(&out_format, "%o ", &fmt_len);
2262 if (show_pax) xstrcat(&out_format, "%x ", &fmt_len);
2263 if (show_perms) xstrcat(&out_format, "%O ", &fmt_len);
2264 if (show_size) xstrcat(&out_format, "%Z ", &fmt_len);
2265 if (show_endian) xstrcat(&out_format, "%D ", &fmt_len);
2266 if (show_osabi) xstrcat(&out_format, "%I ", &fmt_len);
2267 if (show_eabi) xstrcat(&out_format, "%Y ", &fmt_len);
2268 if (show_phdr) xstrcat(&out_format, "%e ", &fmt_len);
2269 if (show_textrel) xstrcat(&out_format, "%t ", &fmt_len);
2270 if (show_rpath) xstrcat(&out_format, "%r ", &fmt_len);
2271 if (show_needed) xstrcat(&out_format, "%n ", &fmt_len);
2272 if (show_interp) xstrcat(&out_format, "%i ", &fmt_len);
2273 if (show_bind) xstrcat(&out_format, "%b ", &fmt_len);
2274 if (show_soname) xstrcat(&out_format, "%S ", &fmt_len);
2275 if (show_textrels) xstrcat(&out_format, "%T ", &fmt_len);
2276 if (find_sym) xstrcat(&out_format, "%s ", &fmt_len);
2277 if (find_section) xstrcat(&out_format, "%k ", &fmt_len);
2278 if (find_lib) xstrcat(&out_format, "%N ", &fmt_len);
2279 if (!be_quiet) xstrcat(&out_format, "%F ", &fmt_len);
2280 }
2281 if (be_verbose > 2) printf("Format: %s\n", out_format);
2282
2283 /* now lets actually do the scanning */
2284 if (load_cache_config)
2285 load_ld_cache_config(__PAX_UTILS_DEFAULT_LD_CACHE_CONFIG);
2286 if (scan_ldpath) scanelf_ldpath();
2287 if (scan_envpath) scanelf_envpath();
2288 if (!from_file && optind == argc && ttyname(0) == NULL && !scan_ldpath && !scan_envpath)
2289 from_file = "-";
2290 if (from_file) {
2291 scanelf_from_file(from_file);
2292 from_file = *argv;
2293 }
2294 if (optind == argc && !scan_ldpath && !scan_envpath && !from_file)
2295 err("Nothing to scan !?");
2296 while (optind < argc) {
2297 search_path = argv[optind++];
2298 ret = scanelf_dir(search_path);
2299 }
2300
2301 /* clean up */
2302 xarrayfree(ldpaths);
2303 xarrayfree(find_lib_arr);
2304 xarrayfree(find_section_arr);
2305 free(find_lib);
2306 free(find_section);
2307
2308 if (ldcache != 0)
2309 munmap(ldcache, ldcache_size);
2310 return ret;
2311 }
2312
2313 static char **get_split_env(const char *envvar)
2314 {
2315 const char *delims = " \t\n";
2316 char **envvals = NULL;
2317 char *env, *s;
2318 int nentry;
2319
2320 if ((env = getenv(envvar)) == NULL)
2321 return NULL;
2322
2323 env = xstrdup(env);
2324 if (env == NULL)
2325 return NULL;
2326
2327 s = strtok(env, delims);
2328 if (s == NULL) {
2329 free(env);
2330 return NULL;
2331 }
2332
2333 nentry = 0;
2334 while (s != NULL) {
2335 ++nentry;
2336 envvals = xrealloc(envvals, sizeof(*envvals) * (nentry+1));
2337 envvals[nentry-1] = s;
2338 s = strtok(NULL, delims);
2339 }
2340 envvals[nentry] = NULL;
2341
2342 /* don't want to free(env) as it contains the memory that backs
2343 * the envvals array of strings */
2344 return envvals;
2345 }
2346
2347 static void parseenv(void)
2348 {
2349 color_init(false);
2350 qa_textrels = get_split_env("QA_TEXTRELS");
2351 qa_execstack = get_split_env("QA_EXECSTACK");
2352 qa_wx_load = get_split_env("QA_WX_LOAD");
2353 }
2354
2355 #ifdef __PAX_UTILS_CLEANUP
2356 static void cleanup(void)
2357 {
2358 free(out_format);
2359 free(qa_textrels);
2360 free(qa_execstack);
2361 free(qa_wx_load);
2362 }
2363 #endif
2364
2365 int main(int argc, char *argv[])
2366 {
2367 int ret;
2368 if (argc < 2)
2369 usage(EXIT_FAILURE);
2370 parseenv();
2371 ret = parseargs(argc, argv);
2372 fclose(stdout);
2373 #ifdef __PAX_UTILS_CLEANUP
2374 cleanup();
2375 warn("The calls to add/delete heap should be off:\n"
2376 "\t- 1 due to the out_buffer not being freed in scanelf_fileat()\n"
2377 "\t- 1 per QA_TEXTRELS/QA_EXECSTACK/QA_WX_LOAD");
2378 #endif
2379 return ret;
2380 }
2381
2382 /* Match filename against entries in matchlist, return TRUE
2383 * if the file is listed */
2384 static int file_matches_list(const char *filename, char **matchlist)
2385 {
2386 char **file;
2387 char *match;
2388 char buf[__PAX_UTILS_PATH_MAX];
2389
2390 if (matchlist == NULL)
2391 return 0;
2392
2393 for (file = matchlist; *file != NULL; file++) {
2394 if (search_path) {
2395 snprintf(buf, sizeof(buf), "%s%s", search_path, *file);
2396 match = buf;
2397 } else {
2398 match = *file;
2399 }
2400 if (fnmatch(match, filename, 0) == 0)
2401 return 1;
2402 }
2403 return 0;
2404 }

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