/[gentoo-projects]/pax-utils/scanelf.c
Gentoo

Contents of /pax-utils/scanelf.c

Parent Directory Parent Directory | Revision Log Revision Log


Revision 1.82 - (show annotations) (download) (as text)
Sun Jun 19 05:39:31 2005 UTC (9 years, 6 months ago) by vapier
Branch: MAIN
Changes since 1.81: +62 -67 lines
File MIME type: text/x-csrc
change textrel scanner to check .text section instead of PT_LOAD ... also update -a to not include bind/interp info

1 /*
2 * Copyright 2003-2005 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 1.81 2005/06/13 03:35:41 vapier Exp $
5 *
6 ********************************************************************
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation; either version 2 of the
10 * License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
20 * MA 02111-1307, USA.
21 */
22
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <sys/types.h>
26 #include <libgen.h>
27 #include <limits.h>
28 #define __USE_GNU
29 #include <string.h>
30 #include <errno.h>
31 #include <unistd.h>
32 #include <sys/stat.h>
33 #include <dirent.h>
34 #include <getopt.h>
35 #include <assert.h>
36 #include "paxelf.h"
37
38 static const char *rcsid = "$Id: scanelf.c,v 1.81 2005/06/13 03:35:41 vapier Exp $";
39 #define argv0 "scanelf"
40
41 #define IS_MODIFIER(c) (c == '%' || c == '#')
42
43
44
45 /* prototypes */
46 static void scanelf_file(const char *filename);
47 static void scanelf_dir(const char *path);
48 static void scanelf_ldpath();
49 static void scanelf_envpath();
50 static void usage(int status);
51 static void parseargs(int argc, char *argv[]);
52 static char *xstrdup(const char *s);
53 static void *xmalloc(size_t size);
54 static void xstrcat(char **dst, const char *src, size_t *curr_len);
55 static inline void xchrcat(char **dst, const char append, size_t *curr_len);
56
57 /* variables to control behavior */
58 static char *ldpaths[256];
59 static char scan_ldpath = 0;
60 static char scan_envpath = 0;
61 static char scan_symlink = 1;
62 static char dir_recurse = 0;
63 static char dir_crossmount = 1;
64 static char show_pax = 0;
65 static char show_phdr = 0;
66 static char show_textrel = 0;
67 static char show_rpath = 0;
68 static char show_needed = 0;
69 static char show_interp = 0;
70 static char show_bind = 0;
71 static char show_textrels = 0;
72 static char show_banner = 1;
73 static char be_quiet = 0;
74 static char be_verbose = 0;
75 static char be_wewy_wewy_quiet = 0;
76 static char *find_sym = NULL, *versioned_symname = NULL;
77 static char *find_lib = NULL;
78 static char *out_format = NULL;
79 static char *search_path = NULL;
80
81
82
83 /* sub-funcs for scanelf_file() */
84 static void scanelf_file_get_symtabs(elfobj *elf, void **sym, void **tab)
85 {
86 /* find the best SHT_DYNSYM and SHT_STRTAB sections */
87 #define GET_SYMTABS(B) \
88 if (elf->elf_class == ELFCLASS ## B) { \
89 Elf ## B ## _Shdr *symtab, *strtab, *dynsym, *dynstr; \
90 /* debug sections */ \
91 symtab = SHDR ## B (elf_findsecbyname(elf, ".symtab")); \
92 strtab = SHDR ## B (elf_findsecbyname(elf, ".strtab")); \
93 /* runtime sections */ \
94 dynsym = SHDR ## B (elf_findsecbyname(elf, ".dynsym")); \
95 dynstr = SHDR ## B (elf_findsecbyname(elf, ".dynstr")); \
96 if (symtab && dynsym) { \
97 *sym = (void*)((EGET(symtab->sh_size) > EGET(dynsym->sh_size)) ? symtab : dynsym); \
98 } else { \
99 *sym = (void*)(symtab ? symtab : dynsym); \
100 } \
101 if (strtab && dynstr) { \
102 *tab = (void*)((EGET(strtab->sh_size) > EGET(dynstr->sh_size)) ? strtab : dynstr); \
103 } else { \
104 *tab = (void*)(strtab ? strtab : dynstr); \
105 } \
106 }
107 GET_SYMTABS(32)
108 GET_SYMTABS(64)
109 }
110 static char *scanelf_file_pax(elfobj *elf, char *found_pax)
111 {
112 static char *paxflags;
113 static char ret[7];
114 unsigned long i, shown;
115
116 if (!show_pax) return NULL;
117
118 shown = 0;
119 memset(&ret, 0, sizeof(ret));
120
121 if (elf->phdr) {
122 #define SHOW_PAX(B) \
123 if (elf->elf_class == ELFCLASS ## B) { \
124 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
125 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
126 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
127 if (EGET(phdr[i].p_type) != PT_PAX_FLAGS) \
128 continue; \
129 if (be_quiet && (EGET(phdr[i].p_flags) == 10240)) \
130 continue; \
131 memcpy(ret, pax_short_pf_flags(EGET(phdr[i].p_flags)), 6); \
132 *found_pax = 1; \
133 ++shown; \
134 break; \
135 } \
136 }
137 SHOW_PAX(32)
138 SHOW_PAX(64)
139 }
140
141 /* fall back to EI_PAX if no PT_PAX was found */
142 if (!*ret) {
143 paxflags = pax_short_hf_flags(EI_PAX_FLAGS(elf));
144 if (!be_quiet || (be_quiet && EI_PAX_FLAGS(elf))) {
145 *found_pax = 1;
146 return paxflags;
147 }
148 strncpy(ret, paxflags, sizeof(ret));
149 }
150
151 if (be_quiet && !shown)
152 return NULL;
153 return ret;
154
155 }
156 static char *scanelf_file_phdr(elfobj *elf, char *found_phdr, char *found_relro, char *found_load)
157 {
158 static char ret[12];
159 char *found;
160 unsigned long i, off, shown, check_flags;
161 unsigned char multi_stack, multi_relro, multi_load;
162
163 if (!show_phdr) return NULL;
164
165 memcpy(ret, "--- --- ---\0", 12);
166
167 shown = 0;
168 multi_stack = multi_relro = multi_load = 0;
169
170 if (elf->phdr) {
171 #define SHOW_PHDR(B) \
172 if (elf->elf_class == ELFCLASS ## B) { \
173 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
174 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
175 uint32_t flags; \
176 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
177 if (EGET(phdr[i].p_type) == PT_GNU_STACK) { \
178 if (multi_stack++) warnf("%s: multiple PT_GNU_STACK's !?", elf->filename); \
179 found = found_phdr; \
180 off = 0; \
181 check_flags = PF_X; \
182 } else if (EGET(phdr[i].p_type) == PT_GNU_RELRO) { \
183 if (multi_relro++) warnf("%s: multiple PT_GNU_RELRO's !?", elf->filename); \
184 found = found_relro; \
185 off = 4; \
186 check_flags = PF_X; \
187 } else if (EGET(phdr[i].p_type) == PT_LOAD) { \
188 if (multi_load++ > 2) warnf("%s: more than 2 PT_LOAD's !?", elf->filename); \
189 found = found_load; \
190 off = 8; \
191 check_flags = PF_W|PF_X; \
192 } else \
193 continue; \
194 flags = EGET(phdr[i].p_flags); \
195 if (be_quiet && ((flags & check_flags) != check_flags)) \
196 continue; \
197 memcpy(ret+off, gnu_short_stack_flags(flags), 3); \
198 *found = 1; \
199 ++shown; \
200 } \
201 }
202 SHOW_PHDR(32)
203 SHOW_PHDR(64)
204 }
205
206 if (be_quiet && !shown)
207 return NULL;
208 else
209 return ret;
210 }
211 static char *scanelf_file_textrel(elfobj *elf, char *found_textrel)
212 {
213 static char ret[] = "TEXTREL";
214 unsigned long i;
215
216 if (!show_textrel && !show_textrels) return NULL;
217
218 if (elf->phdr) {
219 #define SHOW_TEXTREL(B) \
220 if (elf->elf_class == ELFCLASS ## B) { \
221 Elf ## B ## _Dyn *dyn; \
222 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
223 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
224 Elf ## B ## _Off offset; \
225 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
226 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
227 offset = EGET(phdr[i].p_offset); \
228 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
229 dyn = DYN ## B (elf->data + offset); \
230 while (EGET(dyn->d_tag) != DT_NULL) { \
231 if (EGET(dyn->d_tag) == DT_TEXTREL) { /*dyn->d_tag != DT_FLAGS)*/ \
232 *found_textrel = 1; \
233 /*if (dyn->d_un.d_val & DF_TEXTREL)*/ \
234 return (be_wewy_wewy_quiet ? NULL : ret); \
235 } \
236 ++dyn; \
237 } \
238 } }
239 SHOW_TEXTREL(32)
240 SHOW_TEXTREL(64)
241 }
242
243 if (be_quiet || be_wewy_wewy_quiet)
244 return NULL;
245 else
246 return (char *)" - ";
247 }
248 static char *scanelf_file_textrels(elfobj *elf, char *found_textrels, char *found_textrel)
249 {
250 unsigned long s, r, rmax;
251 void *symtab_void, *strtab_void, *text_void;
252
253 if (!show_textrels) return NULL;
254
255 /* don't search for TEXTREL's if the ELF doesn't have any */
256 if (!*found_textrel) scanelf_file_textrel(elf, found_textrel);
257 if (!*found_textrel) return NULL;
258
259 scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
260 text_void = elf_findsecbyname(elf, ".text");
261
262 if (symtab_void && strtab_void && text_void && elf->shdr) {
263 #define SHOW_TEXTRELS(B) \
264 if (elf->elf_class == ELFCLASS ## B) { \
265 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
266 Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \
267 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
268 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
269 Elf ## B ## _Shdr *text = SHDR ## B (text_void); \
270 Elf ## B ## _Addr vaddr = EGET(text->sh_addr); \
271 uint ## B ## _t memsz = EGET(text->sh_size); \
272 Elf ## B ## _Rel *rel; \
273 Elf ## B ## _Rela *rela; \
274 /* search the section headers for relocations */ \
275 for (s = 0; s < EGET(ehdr->e_shnum); ++s) { \
276 uint32_t sh_type = EGET(shdr[s].sh_type); \
277 if (sh_type == SHT_REL) { \
278 rel = REL ## B (elf->data + EGET(shdr[s].sh_offset)); \
279 rela = NULL; \
280 rmax = EGET(shdr[s].sh_size) / sizeof(*rel); \
281 } else if (sh_type == SHT_RELA) { \
282 rel = NULL; \
283 rela = RELA ## B (elf->data + EGET(shdr[s].sh_offset)); \
284 rmax = EGET(shdr[s].sh_size) / sizeof(*rela); \
285 } else \
286 continue; \
287 /* now see if any of the relocs are in the .text */ \
288 for (r = 0; r < rmax; ++r) { \
289 unsigned long sym_max; \
290 Elf ## B ## _Addr offset_tmp; \
291 Elf ## B ## _Sym *func; \
292 Elf ## B ## _Sym *sym; \
293 Elf ## B ## _Addr r_offset; \
294 uint ## B ## _t r_info; \
295 if (sh_type == SHT_REL) { \
296 r_offset = EGET(rel[r].r_offset); \
297 r_info = EGET(rel[r].r_info); \
298 } else { \
299 r_offset = EGET(rela[r].r_offset); \
300 r_info = EGET(rela[r].r_info); \
301 } \
302 /* make sure this relocation is inside of the .text */ \
303 if (r_offset < vaddr || r_offset >= vaddr + memsz) { \
304 if (be_verbose <= 2) continue; \
305 } else \
306 *found_textrels = 1; \
307 /* locate this relocation symbol name */ \
308 sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \
309 sym_max = ELF ## B ## _R_SYM(r_info); \
310 if (sym_max * EGET(symtab->sh_entsize) < symtab->sh_size) \
311 sym += sym_max; \
312 else \
313 sym = NULL; \
314 sym_max = EGET(symtab->sh_size) / EGET(symtab->sh_entsize); \
315 /* show the raw details about this reloc */ \
316 printf("\tTEXTREL %s: ", elf->base_filename); \
317 if (sym && sym->st_name) \
318 printf("%s", (char*)(elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name))); \
319 else \
320 printf("(NULL: fake?)"); \
321 printf(" [0x%lX]", (unsigned long)r_offset); \
322 /* now try to find the closest symbol that this rel is probably in */ \
323 sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \
324 func = NULL; \
325 offset_tmp = 0; \
326 while (sym_max--) { \
327 if (EGET(sym->st_value) < r_offset && EGET(sym->st_value) > offset_tmp) { \
328 func = sym; \
329 offset_tmp = EGET(sym->st_value); \
330 } \
331 ++sym; \
332 } \
333 printf(" in "); \
334 if (func && func->st_name) \
335 printf("%s", (char*)(elf->data + EGET(strtab->sh_offset) + EGET(func->st_name))); \
336 else \
337 printf("(NULL: fake?)"); \
338 printf(" [0x%lX]\n", (unsigned long)offset_tmp); \
339 } \
340 } }
341 SHOW_TEXTRELS(32)
342 SHOW_TEXTRELS(64)
343 }
344 if (!*found_textrels)
345 warnf("ELF %s has TEXTREL markings but doesnt appear to have any real TEXTREL's !?", elf->filename);
346
347 return NULL;
348 }
349 static void scanelf_file_rpath(elfobj *elf, char *found_rpath, char **ret, size_t *ret_len)
350 {
351 unsigned long i, s;
352 char *rpath, *runpath, **r;
353 void *strtbl_void;
354
355 if (!show_rpath) return;
356
357 strtbl_void = elf_findsecbyname(elf, ".dynstr");
358 rpath = runpath = NULL;
359
360 if (elf->phdr && strtbl_void) {
361 #define SHOW_RPATH(B) \
362 if (elf->elf_class == ELFCLASS ## B) { \
363 Elf ## B ## _Dyn *dyn; \
364 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
365 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
366 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
367 Elf ## B ## _Off offset; \
368 Elf ## B ## _Xword word; \
369 /* Scan all the program headers */ \
370 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
371 /* Just scan dynamic headers */ \
372 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
373 offset = EGET(phdr[i].p_offset); \
374 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
375 /* Just scan dynamic RPATH/RUNPATH headers */ \
376 dyn = DYN ## B (elf->data + offset); \
377 while ((word=EGET(dyn->d_tag)) != DT_NULL) { \
378 if (word == DT_RPATH) { \
379 r = &rpath; \
380 } else if (word == DT_RUNPATH) { \
381 r = &runpath; \
382 } else { \
383 ++dyn; \
384 continue; \
385 } \
386 /* Verify the memory is somewhat sane */ \
387 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
388 if (offset < (Elf ## B ## _Off)elf->len) { \
389 if (*r) warn("ELF has multiple %s's !?", get_elfdtype(word)); \
390 *r = (char*)(elf->data + offset); \
391 /* If quiet, don't output paths in ld.so.conf */ \
392 if (be_quiet) { \
393 size_t len; \
394 char *start, *end; \
395 /* note that we only 'chop' off leading known paths. */ \
396 /* since *r is read-only memory, we can only move the ptr forward. */ \
397 start = *r; \
398 /* scan each path in : delimited list */ \
399 while (start) { \
400 end = strchr(start, ':'); \
401 len = (end ? abs(end - start) : strlen(start)); \
402 for (s = 0; ldpaths[s]; ++s) { \
403 if (!strncmp(ldpaths[s], start, len) && !ldpaths[s][len]) { \
404 *r = (end ? end + 1 : NULL); \
405 break; \
406 } \
407 } \
408 if (!*r || !ldpaths[s] || !end) \
409 start = NULL; \
410 else \
411 start = start + len + 1; \
412 } \
413 } \
414 if (*r) *found_rpath = 1; \
415 } \
416 ++dyn; \
417 } \
418 } }
419 SHOW_RPATH(32)
420 SHOW_RPATH(64)
421 }
422
423 if (be_wewy_wewy_quiet) return;
424
425 if (rpath && runpath) {
426 if (!strcmp(rpath, runpath)) {
427 xstrcat(ret, runpath, ret_len);
428 } else {
429 fprintf(stderr, "RPATH [%s] != RUNPATH [%s]\n", rpath, runpath);
430 xchrcat(ret, '{', ret_len);
431 xstrcat(ret, rpath, ret_len);
432 xchrcat(ret, ',', ret_len);
433 xstrcat(ret, runpath, ret_len);
434 xchrcat(ret, '}', ret_len);
435 }
436 } else if (rpath || runpath)
437 xstrcat(ret, (runpath ? runpath : rpath), ret_len);
438 else if (!be_quiet)
439 xstrcat(ret, " - ", ret_len);
440 }
441 static char *scanelf_file_needed_lib(elfobj *elf, char *found_needed, char *found_lib, int op, char **ret, size_t *ret_len)
442 {
443 unsigned long i;
444 char *needed;
445 void *strtbl_void;
446
447 if ((op==0 && !show_needed) || (op==1 && !find_lib)) return NULL;
448
449 strtbl_void = elf_findsecbyname(elf, ".dynstr");
450
451 if (elf->phdr && strtbl_void) {
452 #define SHOW_NEEDED(B) \
453 if (elf->elf_class == ELFCLASS ## B) { \
454 Elf ## B ## _Dyn *dyn; \
455 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
456 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
457 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
458 Elf ## B ## _Off offset; \
459 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
460 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
461 offset = EGET(phdr[i].p_offset); \
462 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
463 dyn = DYN ## B (elf->data + offset); \
464 while (EGET(dyn->d_tag) != DT_NULL) { \
465 if (EGET(dyn->d_tag) == DT_NEEDED) { \
466 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
467 if (offset >= (Elf ## B ## _Off)elf->len) { \
468 ++dyn; \
469 continue; \
470 } \
471 needed = (char*)(elf->data + offset); \
472 if (op == 0) { \
473 if (!be_wewy_wewy_quiet) { \
474 if (*found_needed) xchrcat(ret, ',', ret_len); \
475 xstrcat(ret, needed, ret_len); \
476 } \
477 *found_needed = 1; \
478 } else { \
479 if (!strcmp(find_lib, needed)) { \
480 *found_lib = 1; \
481 return (be_wewy_wewy_quiet ? NULL : find_lib); \
482 } \
483 } \
484 } \
485 ++dyn; \
486 } \
487 } }
488 SHOW_NEEDED(32)
489 SHOW_NEEDED(64)
490 }
491
492 return NULL;
493 }
494 static char *scanelf_file_interp(elfobj *elf, char *found_interp)
495 {
496 void *strtbl_void;
497
498 if (!show_interp) return NULL;
499
500 strtbl_void = elf_findsecbyname(elf, ".interp");
501
502 if (strtbl_void) {
503 #define SHOW_INTERP(B) \
504 if (elf->elf_class == ELFCLASS ## B) { \
505 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
506 *found_interp = 1; \
507 return (be_wewy_wewy_quiet ? NULL : elf->data + EGET(strtbl->sh_offset)); \
508 }
509 SHOW_INTERP(32)
510 SHOW_INTERP(64)
511 }
512 return NULL;
513 }
514 static char *scanelf_file_bind(elfobj *elf, char *found_bind)
515 {
516 unsigned long i;
517 struct stat s;
518
519 if (!show_bind) return NULL;
520 if (!elf->phdr) return NULL;
521
522 #define SHOW_BIND(B) \
523 if (elf->elf_class == ELFCLASS ## B) { \
524 Elf ## B ## _Dyn *dyn; \
525 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
526 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
527 Elf ## B ## _Off offset; \
528 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
529 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
530 offset = EGET(phdr[i].p_offset); \
531 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
532 dyn = DYN ## B (elf->data + offset); \
533 while (EGET(dyn->d_tag) != DT_NULL) { \
534 if (EGET(dyn->d_tag) == DT_BIND_NOW || \
535 (EGET(dyn->d_tag) == DT_FLAGS && EGET(dyn->d_un.d_val) & DF_BIND_NOW)) \
536 { \
537 if (be_quiet) return NULL; \
538 *found_bind = 1; \
539 return (char *)(be_wewy_wewy_quiet ? NULL : "NOW"); \
540 } \
541 ++dyn; \
542 } \
543 } \
544 }
545 SHOW_BIND(32)
546 SHOW_BIND(64)
547
548 if (be_wewy_wewy_quiet) return NULL;
549
550 if (be_quiet && !fstat(elf->fd, &s) && !(s.st_mode & S_ISUID || s.st_mode & S_ISGID)) {
551 return NULL;
552 } else {
553 *found_bind = 1;
554 return (char *) "LAZY";
555 }
556 }
557 static char *scanelf_file_sym(elfobj *elf, char *found_sym)
558 {
559 unsigned long i;
560 void *symtab_void, *strtab_void;
561
562 if (!find_sym) return NULL;
563
564 scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
565
566 if (symtab_void && strtab_void) {
567 #define FIND_SYM(B) \
568 if (elf->elf_class == ELFCLASS ## B) { \
569 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
570 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
571 Elf ## B ## _Sym *sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \
572 unsigned long cnt = EGET(symtab->sh_size) / EGET(symtab->sh_entsize); \
573 char *symname; \
574 for (i = 0; i < cnt; ++i) { \
575 if (sym->st_name) { \
576 symname = (char *)(elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name)); \
577 if (*find_sym == '*') { \
578 printf("%s(%s) %5lX %15s %s\n", \
579 ((*found_sym == 0) ? "\n\t" : "\t"), \
580 elf->base_filename, \
581 (long)sym->st_size, \
582 (char *)get_elfstttype(sym->st_info), \
583 symname); \
584 *found_sym = 1; \
585 } else if ((strcmp(find_sym, symname) == 0) || \
586 (strcmp(symname, versioned_symname) == 0)) \
587 (*found_sym)++; \
588 } \
589 ++sym; \
590 } }
591 FIND_SYM(32)
592 FIND_SYM(64)
593 }
594
595 if (be_wewy_wewy_quiet) return NULL;
596
597 if (*find_sym != '*' && *found_sym)
598 return find_sym;
599 if (be_quiet)
600 return NULL;
601 else
602 return (char *)" - ";
603 }
604 /* scan an elf file and show all the fun stuff */
605 #define prints(str) write(fileno(stdout), str, strlen(str))
606 static void scanelf_file(const char *filename)
607 {
608 unsigned long i;
609 char found_pax, found_phdr, found_relro, found_load, found_textrel,
610 found_rpath, found_needed, found_interp, found_bind,
611 found_sym, found_lib, found_file, found_textrels;
612 elfobj *elf;
613 struct stat st;
614 static char *out_buffer = NULL;
615 static size_t out_len;
616
617 /* make sure 'filename' exists */
618 if (lstat(filename, &st) == -1) {
619 if (be_verbose > 2) printf("%s: does not exist\n", filename);
620 return;
621 }
622 /* always handle regular files and handle symlinked files if no -y */
623 if (S_ISLNK(st.st_mode)) {
624 if (!scan_symlink) return;
625 stat(filename, &st);
626 }
627 if (!S_ISREG(st.st_mode)) {
628 if (be_verbose > 2) printf("%s: skipping non-file\n", filename);
629 return;
630 }
631
632 found_pax = found_phdr = found_relro = found_load = found_textrel = \
633 found_rpath = found_needed = found_interp = found_bind = \
634 found_sym = found_lib = found_file = found_textrels = 0;
635
636 /* verify this is real ELF */
637 if ((elf = readelf(filename)) == NULL) {
638 if (be_verbose > 2) printf("%s: not an ELF\n", filename);
639 return;
640 }
641
642 if (be_verbose > 1)
643 printf("%s: scanning file {%s,%s}\n", filename,
644 get_elfeitype(EI_CLASS, elf->elf_class),
645 get_elfeitype(EI_DATA, elf->data[EI_DATA]));
646 else if (be_verbose)
647 printf("%s: scanning file\n", filename);
648
649 /* init output buffer */
650 if (!out_buffer) {
651 out_len = sizeof(char) * 80;
652 out_buffer = (char*)xmalloc(out_len);
653 }
654 *out_buffer = '\0';
655
656 /* show the header */
657 if (!be_quiet && show_banner) {
658 for (i = 0; out_format[i]; ++i) {
659 if (!IS_MODIFIER(out_format[i])) continue;
660
661 switch (out_format[++i]) {
662 case '%': break;
663 case '#': break;
664 case 'F':
665 case 'p':
666 case 'f': prints("FILE "); found_file = 1; break;
667 case 'o': prints(" TYPE "); break;
668 case 'x': prints(" PAX "); break;
669 case 'e': prints("STK/REL/PTL "); break;
670 case 't': prints("TEXTREL "); break;
671 case 'r': prints("RPATH "); break;
672 case 'n': prints("NEEDED "); break;
673 case 'i': prints("INTERP "); break;
674 case 'b': prints("BIND "); break;
675 case 's': prints("SYM "); break;
676 case 'N': prints("LIB "); break;
677 case 'T': prints("TEXTRELS "); break;
678 default: warnf("'%c' has no title ?", out_format[i]);
679 }
680 }
681 if (!found_file) prints("FILE ");
682 prints("\n");
683 found_file = 0;
684 show_banner = 0;
685 }
686
687 /* dump all the good stuff */
688 for (i = 0; out_format[i]; ++i) {
689 const char *out;
690 const char *tmp;
691
692 /* make sure we trim leading spaces in quiet mode */
693 if (be_quiet && *out_buffer == ' ' && !out_buffer[1])
694 *out_buffer = '\0';
695
696 if (!IS_MODIFIER(out_format[i])) {
697 xchrcat(&out_buffer, out_format[i], &out_len);
698 continue;
699 }
700
701 out = NULL;
702 be_wewy_wewy_quiet = (out_format[i] == '#');
703 switch (out_format[++i]) {
704 case '%':
705 case '#':
706 xchrcat(&out_buffer, out_format[i], &out_len); break;
707 case 'F':
708 found_file = 1;
709 if (be_wewy_wewy_quiet) break;
710 xstrcat(&out_buffer, filename, &out_len);
711 break;
712 case 'p':
713 found_file = 1;
714 if (be_wewy_wewy_quiet) break;
715 tmp = filename;
716 if (search_path) {
717 ssize_t len_search = strlen(search_path);
718 ssize_t len_file = strlen(filename);
719 if (!strncmp(filename, search_path, len_search) && \
720 len_file > len_search)
721 tmp += len_search;
722 if (*tmp == '/' && search_path[len_search-1] == '/') tmp++;
723 }
724 xstrcat(&out_buffer, tmp, &out_len);
725 break;
726 case 'f':
727 found_file = 1;
728 if (be_wewy_wewy_quiet) break;
729 tmp = strrchr(filename, '/');
730 tmp = (tmp == NULL ? filename : tmp+1);
731 xstrcat(&out_buffer, tmp, &out_len);
732 break;
733 case 'o': out = get_elfetype(elf); break;
734 case 'x': out = scanelf_file_pax(elf, &found_pax); break;
735 case 'e': out = scanelf_file_phdr(elf, &found_phdr, &found_relro, &found_load); break;
736 case 't': out = scanelf_file_textrel(elf, &found_textrel); break;
737 case 'T': out = scanelf_file_textrels(elf, &found_textrels, &found_textrel); break;
738 case 'r': scanelf_file_rpath(elf, &found_rpath, &out_buffer, &out_len); break;
739 case 'n':
740 case 'N': out = scanelf_file_needed_lib(elf, &found_needed, &found_lib, (out_format[i]=='N'), &out_buffer, &out_len); break;
741 case 'i': out = scanelf_file_interp(elf, &found_interp); break;
742 case 'b': out = scanelf_file_bind(elf, &found_bind); break;
743 case 's': out = scanelf_file_sym(elf, &found_sym); break;
744 default: warnf("'%c' has no scan code?", out_format[i]);
745 }
746 if (out) xstrcat(&out_buffer, out, &out_len);
747 }
748
749 #define FOUND_SOMETHING() \
750 (found_pax || found_phdr || found_relro || found_load || found_textrel || \
751 found_rpath || found_needed || found_interp || found_bind || \
752 found_sym || found_lib || found_textrels)
753
754 if (!found_file && (!be_quiet || (be_quiet && FOUND_SOMETHING()))) {
755 xchrcat(&out_buffer, ' ', &out_len);
756 xstrcat(&out_buffer, filename, &out_len);
757 }
758 if (!be_quiet || (be_quiet && FOUND_SOMETHING())) {
759 puts(out_buffer);
760 fflush(stdout);
761 }
762
763 unreadelf(elf);
764 }
765
766 /* scan a directory for ET_EXEC files and print when we find one */
767 static void scanelf_dir(const char *path)
768 {
769 register DIR *dir;
770 register struct dirent *dentry;
771 struct stat st_top, st;
772 char buf[_POSIX_PATH_MAX];
773 size_t pathlen = 0, len = 0;
774
775 /* make sure path exists */
776 if (lstat(path, &st_top) == -1) {
777 if (be_verbose > 2) printf("%s: does not exist\n", path);
778 return;
779 }
780
781 /* ok, if it isn't a directory, assume we can open it */
782 if (!S_ISDIR(st_top.st_mode)) {
783 scanelf_file(path);
784 return;
785 }
786
787 /* now scan the dir looking for fun stuff */
788 if ((dir = opendir(path)) == NULL) {
789 warnf("could not opendir %s: %s", path, strerror(errno));
790 return;
791 }
792 if (be_verbose) printf("%s: scanning dir\n", path);
793
794 pathlen = strlen(path);
795 while ((dentry = readdir(dir))) {
796 if (!strcmp(dentry->d_name, ".") || !strcmp(dentry->d_name, ".."))
797 continue;
798 len = (pathlen + 1 + strlen(dentry->d_name) + 1);
799 if (len >= sizeof(buf)) {
800 warnf("Skipping '%s': len > sizeof(buf); %lu > %lu\n", path,
801 (unsigned long)len, (unsigned long)sizeof(buf));
802 continue;
803 }
804 sprintf(buf, "%s/%s", path, dentry->d_name);
805 if (lstat(buf, &st) != -1) {
806 if (S_ISREG(st.st_mode))
807 scanelf_file(buf);
808 else if (dir_recurse && S_ISDIR(st.st_mode)) {
809 if (dir_crossmount || (st_top.st_dev == st.st_dev))
810 scanelf_dir(buf);
811 }
812 }
813 }
814 closedir(dir);
815 }
816
817 static int scanelf_from_file(char *filename)
818 {
819 FILE *fp = NULL;
820 char *p;
821 char path[_POSIX_PATH_MAX];
822
823 if (((strcmp(filename, "-")) == 0) && (ttyname(0) == NULL))
824 fp = stdin;
825 else if ((fp = fopen(filename, "r")) == NULL)
826 return 1;
827
828 while ((fgets(path, _POSIX_PATH_MAX, fp)) != NULL) {
829 if ((p = strchr(path, '\n')) != NULL)
830 *p = 0;
831 search_path = path;
832 scanelf_dir(path);
833 }
834 if (fp != stdin)
835 fclose(fp);
836 return 0;
837 }
838
839 static void load_ld_so_conf()
840 {
841 FILE *fp = NULL;
842 char *p;
843 char path[_POSIX_PATH_MAX];
844 int i = 0;
845
846 if ((fp = fopen("/etc/ld.so.conf", "r")) == NULL)
847 return;
848
849 while ((fgets(path, _POSIX_PATH_MAX, fp)) != NULL) {
850 if (*path != '/')
851 continue;
852
853 if ((p = strrchr(path, '\r')) != NULL)
854 *p = 0;
855 if ((p = strchr(path, '\n')) != NULL)
856 *p = 0;
857
858 ldpaths[i++] = xstrdup(path);
859
860 if (i + 1 == sizeof(ldpaths) / sizeof(*ldpaths))
861 break;
862 }
863 ldpaths[i] = NULL;
864
865 fclose(fp);
866 }
867
868 /* scan /etc/ld.so.conf for paths */
869 static void scanelf_ldpath()
870 {
871 char scan_l, scan_ul, scan_ull;
872 int i = 0;
873
874 if (!ldpaths[0])
875 err("Unable to load any paths from ld.so.conf");
876
877 scan_l = scan_ul = scan_ull = 0;
878
879 while (ldpaths[i]) {
880 if (!scan_l && !strcmp(ldpaths[i], "/lib")) scan_l = 1;
881 if (!scan_ul && !strcmp(ldpaths[i], "/usr/lib")) scan_ul = 1;
882 if (!scan_ull && !strcmp(ldpaths[i], "/usr/local/lib")) scan_ull = 1;
883 scanelf_dir(ldpaths[i]);
884 ++i;
885 }
886
887 if (!scan_l) scanelf_dir("/lib");
888 if (!scan_ul) scanelf_dir("/usr/lib");
889 if (!scan_ull) scanelf_dir("/usr/local/lib");
890 }
891
892 /* scan env PATH for paths */
893 static void scanelf_envpath()
894 {
895 char *path, *p;
896
897 path = getenv("PATH");
898 if (!path)
899 err("PATH is not set in your env !");
900 path = xstrdup(path);
901
902 while ((p = strrchr(path, ':')) != NULL) {
903 scanelf_dir(p + 1);
904 *p = 0;
905 }
906
907 free(path);
908 }
909
910
911
912 /* usage / invocation handling functions */
913 #define PARSE_FLAGS "plRmyxetrnibs:N:TaqvF:f:o:BhV"
914 #define a_argument required_argument
915 static struct option const long_opts[] = {
916 {"path", no_argument, NULL, 'p'},
917 {"ldpath", no_argument, NULL, 'l'},
918 {"recursive", no_argument, NULL, 'R'},
919 {"mount", no_argument, NULL, 'm'},
920 {"symlink", no_argument, NULL, 'y'},
921 {"pax", no_argument, NULL, 'x'},
922 {"header", no_argument, NULL, 'e'},
923 {"textrel", no_argument, NULL, 't'},
924 {"rpath", no_argument, NULL, 'r'},
925 {"needed", no_argument, NULL, 'n'},
926 {"interp", no_argument, NULL, 'i'},
927 {"bind", no_argument, NULL, 'b'},
928 {"symbol", a_argument, NULL, 's'},
929 {"lib", a_argument, NULL, 'N'},
930 {"textrels", no_argument, NULL, 'T'},
931 {"all", no_argument, NULL, 'a'},
932 {"quiet", no_argument, NULL, 'q'},
933 {"verbose", no_argument, NULL, 'v'},
934 {"format", a_argument, NULL, 'F'},
935 {"from", a_argument, NULL, 'f'},
936 {"file", a_argument, NULL, 'o'},
937 {"nobanner", no_argument, NULL, 'B'},
938 {"help", no_argument, NULL, 'h'},
939 {"version", no_argument, NULL, 'V'},
940 {NULL, no_argument, NULL, 0x0}
941 };
942
943 static const char *opts_help[] = {
944 "Scan all directories in PATH environment",
945 "Scan all directories in /etc/ld.so.conf",
946 "Scan directories recursively",
947 "Don't recursively cross mount points",
948 "Don't scan symlinks\n",
949 "Print PaX markings",
950 "Print GNU_STACK/PT_LOAD markings",
951 "Print TEXTREL information",
952 "Print RPATH information",
953 "Print NEEDED information",
954 "Print INTERP information",
955 "Print BIND information",
956 "Find a specified symbol",
957 "Find a specified library",
958 "Locate cause of TEXTREL",
959 "Print all scanned info (-x -e -t -r -b)\n",
960 "Only output 'bad' things",
961 "Be verbose (can be specified more than once)",
962 "Use specified format for output",
963 "Read input stream from a filename",
964 "Write output stream to a filename",
965 "Don't display the header",
966 "Print this help and exit",
967 "Print version and exit",
968 NULL
969 };
970
971 /* display usage and exit */
972 static void usage(int status)
973 {
974 unsigned long i;
975 printf("* Scan ELF binaries for stuff\n\n"
976 "Usage: %s [options] <dir1/file1> [dir2 dirN fileN ...]\n\n", argv0);
977 printf("Options: -[%s]\n", PARSE_FLAGS);
978 for (i = 0; long_opts[i].name; ++i)
979 if (long_opts[i].has_arg == no_argument)
980 printf(" -%c, --%-13s* %s\n", long_opts[i].val,
981 long_opts[i].name, opts_help[i]);
982 else
983 printf(" -%c, --%-6s <arg> * %s\n", long_opts[i].val,
984 long_opts[i].name, opts_help[i]);
985
986 if (status != EXIT_SUCCESS)
987 exit(status);
988
989 puts("\nThe format modifiers for the -F option are:");
990 puts(" F Filename \tx PaX Flags \te STACK/RELRO");
991 puts(" t TEXTREL \tr RPATH \tn NEEDED");
992 puts(" i INTERP \tb BIND \ts symbol");
993 puts(" N library \to Type \tT TEXTRELs");
994 puts(" p filename (with search path removed)");
995 puts(" f base filename");
996 puts("Prefix each modifier with '%' (verbose) or '#' (silent)");
997
998 exit(status);
999 }
1000
1001 /* parse command line arguments and preform needed actions */
1002 static void parseargs(int argc, char *argv[])
1003 {
1004 int i;
1005 char *from_file = NULL;
1006
1007 opterr = 0;
1008 while ((i=getopt_long(argc, argv, PARSE_FLAGS, long_opts, NULL)) != -1) {
1009 switch (i) {
1010
1011 case 'V':
1012 printf("pax-utils-%s: %s compiled %s\n%s\n"
1013 "%s written for Gentoo by <solar and vapier @ gentoo.org>\n",
1014 VERSION, __FILE__, __DATE__, rcsid, argv0);
1015 exit(EXIT_SUCCESS);
1016 break;
1017 case 'h': usage(EXIT_SUCCESS); break;
1018 case 'f':
1019 if (from_file) err("Don't specify -f twice");
1020 from_file = xstrdup(optarg);
1021 break;
1022 case 'o': {
1023 FILE *fp = NULL;
1024 if ((fp = freopen(optarg, "w", stdout)) == NULL)
1025 err("Could not open output stream '%s': %s", optarg, strerror(errno));
1026 SET_STDOUT(fp);
1027 break;
1028 }
1029
1030 case 's': {
1031 size_t len;
1032 if (find_sym) err("Don't specify -s twice");
1033 find_sym = xstrdup(optarg);
1034 len = strlen(find_sym) + 1;
1035 versioned_symname = (char*)xmalloc(sizeof(char) * (len+1));
1036 sprintf(versioned_symname, "%s@", find_sym);
1037 break;
1038 }
1039 case 'N': {
1040 if (find_lib) err("Don't specify -N twice");
1041 find_lib = xstrdup(optarg);
1042 break;
1043 }
1044
1045 case 'F': {
1046 if (out_format) err("Don't specify -F twice");
1047 out_format = xstrdup(optarg);
1048 break;
1049 }
1050
1051 case 'y': scan_symlink = 0; break;
1052 case 'B': show_banner = 0; break;
1053 case 'l': scan_ldpath = 1; break;
1054 case 'p': scan_envpath = 1; break;
1055 case 'R': dir_recurse = 1; break;
1056 case 'm': dir_crossmount = 0; break;
1057 case 'x': show_pax = 1; break;
1058 case 'e': show_phdr = 1; break;
1059 case 't': show_textrel = 1; break;
1060 case 'r': show_rpath = 1; break;
1061 case 'n': show_needed = 1; break;
1062 case 'i': show_interp = 1; break;
1063 case 'b': show_bind = 1; break;
1064 case 'T': show_textrels = 1; break;
1065 case 'q': be_quiet = 1; break;
1066 case 'v': be_verbose = (be_verbose % 20) + 1; break;
1067 case 'a': show_pax = show_phdr = show_textrel = show_rpath = show_bind = 1; break;
1068
1069 case ':':
1070 err("Option missing parameter\n");
1071 case '?':
1072 err("Unknown option\n");
1073 default:
1074 err("Unhandled option '%c'", i);
1075 }
1076 }
1077
1078 /* let the format option override all other options */
1079 if (out_format) {
1080 show_pax = show_phdr = show_textrel = show_rpath = \
1081 show_needed = show_interp = show_bind = show_textrels = 0;
1082 for (i = 0; out_format[i]; ++i) {
1083 if (!IS_MODIFIER(out_format[i])) continue;
1084
1085 switch (out_format[++i]) {
1086 case '%': break;
1087 case '#': break;
1088 case 'F': break;
1089 case 'p': break;
1090 case 'f': break;
1091 case 's': break;
1092 case 'N': break;
1093 case 'o': break;
1094 case 'x': show_pax = 1; break;
1095 case 'e': show_phdr = 1; break;
1096 case 't': show_textrel = 1; break;
1097 case 'r': show_rpath = 1; break;
1098 case 'n': show_needed = 1; break;
1099 case 'i': show_interp = 1; break;
1100 case 'b': show_bind = 1; break;
1101 case 'T': show_textrels = 1; break;
1102 default:
1103 err("Invalid format specifier '%c' (byte %i)",
1104 out_format[i], i+1);
1105 }
1106 }
1107
1108 /* construct our default format */
1109 } else {
1110 size_t fmt_len = 30;
1111 out_format = (char*)xmalloc(sizeof(char) * fmt_len);
1112 if (!be_quiet) xstrcat(&out_format, "%o ", &fmt_len);
1113 if (show_pax) xstrcat(&out_format, "%x ", &fmt_len);
1114 if (show_phdr) xstrcat(&out_format, "%e ", &fmt_len);
1115 if (show_textrel) xstrcat(&out_format, "%t ", &fmt_len);
1116 if (show_rpath) xstrcat(&out_format, "%r ", &fmt_len);
1117 if (show_needed) xstrcat(&out_format, "%n ", &fmt_len);
1118 if (show_interp) xstrcat(&out_format, "%i ", &fmt_len);
1119 if (show_bind) xstrcat(&out_format, "%b ", &fmt_len);
1120 if (show_textrels) xstrcat(&out_format, "%T ", &fmt_len);
1121 if (find_sym) xstrcat(&out_format, "%s ", &fmt_len);
1122 if (find_lib) xstrcat(&out_format, "%N ", &fmt_len);
1123 if (!be_quiet) xstrcat(&out_format, "%F ", &fmt_len);
1124 }
1125 if (be_verbose > 2) printf("Format: %s\n", out_format);
1126
1127 /* now lets actually do the scanning */
1128 if (scan_ldpath || (show_rpath && be_quiet))
1129 load_ld_so_conf();
1130 if (scan_ldpath) scanelf_ldpath();
1131 if (scan_envpath) scanelf_envpath();
1132 if (from_file) {
1133 scanelf_from_file(from_file);
1134 free(from_file);
1135 from_file = *argv;
1136 }
1137 if (optind == argc && !scan_ldpath && !scan_envpath && !from_file)
1138 err("Nothing to scan !?");
1139 while (optind < argc) {
1140 search_path = argv[optind++];
1141 scanelf_dir(search_path);
1142 }
1143
1144 /* clean up */
1145 if (find_sym) {
1146 free(find_sym);
1147 free(versioned_symname);
1148 }
1149 if (find_lib) free(find_lib);
1150 if (out_format) free(out_format);
1151 for (i = 0; ldpaths[i]; ++i)
1152 free(ldpaths[i]);
1153 }
1154
1155
1156
1157 /* utility funcs */
1158 static char *xstrdup(const char *s)
1159 {
1160 char *ret = strdup(s);
1161 if (!ret) err("Could not strdup(): %s", strerror(errno));
1162 return ret;
1163 }
1164
1165 static void *xmalloc(size_t size)
1166 {
1167 void *ret = malloc(size);
1168 if (!ret) err("Could not malloc() %li bytes", (unsigned long)size);
1169 return ret;
1170 }
1171
1172 static void xstrcat(char **dst, const char *src, size_t *curr_len)
1173 {
1174 size_t new_len;
1175
1176 new_len = strlen(*dst) + strlen(src);
1177 if (*curr_len <= new_len) {
1178 *curr_len = new_len + (*curr_len / 2);
1179 *dst = realloc(*dst, *curr_len);
1180 if (!*dst)
1181 err("could not realloc %li bytes", (unsigned long)*curr_len);
1182 }
1183
1184 strcat(*dst, src);
1185 }
1186
1187 static inline void xchrcat(char **dst, const char append, size_t *curr_len)
1188 {
1189 static char my_app[2];
1190 my_app[0] = append;
1191 my_app[1] = '\0';
1192 xstrcat(dst, my_app, curr_len);
1193 }
1194
1195
1196
1197 int main(int argc, char *argv[])
1198 {
1199 if (argc < 2)
1200 usage(EXIT_FAILURE);
1201 parseargs(argc, argv);
1202 fclose(stdout);
1203 #ifdef __BOUNDS_CHECKING_ON
1204 warn("The calls to add/delete heap should be off by 1 due to the out_buffer not being freed in scanelf_file()");
1205 #endif
1206 return EXIT_SUCCESS;
1207 }

  ViewVC Help
Powered by ViewVC 1.1.20