/[gentoo-projects]/pax-utils/scanelf.c
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Revision 1.79 - (show annotations) (download) (as text)
Thu Jun 9 23:53:58 2005 UTC (9 years, 3 months ago) by vapier
Branch: MAIN
Changes since 1.78: +12 -6 lines
File MIME type: text/x-csrc
dont scan for TEXTREL locations if ELF doesnt have any TEXTRELs ... also flush stdout after each line

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 1.78 2005/06/08 22:23:16 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 1.78 2005/06/08 22:23:16 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
117 if (!show_pax) return NULL;
118
119 shown = 0;
120 memset(&ret, 0, sizeof(ret));
121
122 if (elf->phdr) {
123 #define SHOW_PAX(B) \
124 if (elf->elf_class == ELFCLASS ## B) { \
125 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
126 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
127 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
128 if (EGET(phdr[i].p_type) != PT_PAX_FLAGS) \
129 continue; \
130 if (be_quiet && (EGET(phdr[i].p_flags) == 10240)) \
131 continue; \
132 memcpy(ret, pax_short_pf_flags(EGET(phdr[i].p_flags)), 6); \
133 *found_pax = 1; \
134 ++shown; \
135 break; \
136 } \
137 }
138 SHOW_PAX(32)
139 SHOW_PAX(64)
140 }
141
142 /* fall back to EI_PAX if no PT_PAX was found */
143 if (!*ret) {
144 paxflags = pax_short_hf_flags(EI_PAX_FLAGS(elf));
145 if (!be_quiet || (be_quiet && EI_PAX_FLAGS(elf))) {
146 *found_pax = 1;
147 return paxflags;
148 }
149 strncpy(ret, paxflags, sizeof(ret));
150 // ++shown;
151 }
152
153 if (be_quiet && !shown)
154 return NULL;
155 return ret;
156
157 }
158 static char *scanelf_file_phdr(elfobj *elf, char *found_phdr, char *found_relro, char *found_load)
159 {
160 static char ret[12];
161 char *found;
162 unsigned long i, off, shown, check_flags;
163 unsigned char multi_stack, multi_relro, multi_load;
164
165 if (!show_phdr) return NULL;
166
167 memcpy(ret, "--- --- ---\0", 12);
168
169 shown = 0;
170 multi_stack = multi_relro = multi_load = 0;
171
172 if (elf->phdr) {
173 #define SHOW_PHDR(B) \
174 if (elf->elf_class == ELFCLASS ## B) { \
175 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
176 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
177 uint32_t flags; \
178 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
179 if (EGET(phdr[i].p_type) == PT_GNU_STACK) { \
180 if (multi_stack++) warnf("%s: multiple PT_GNU_STACK's !?", elf->filename); \
181 found = found_phdr; \
182 off = 0; \
183 check_flags = PF_X; \
184 } else if (EGET(phdr[i].p_type) == PT_GNU_RELRO) { \
185 if (multi_relro++) warnf("%s: multiple PT_GNU_RELRO's !?", elf->filename); \
186 found = found_relro; \
187 off = 4; \
188 check_flags = PF_X; \
189 } else if (EGET(phdr[i].p_type) == PT_LOAD) { \
190 if (multi_load++ > 2) warnf("%s: more than 2 PT_LOAD's !?", elf->filename); \
191 found = found_load; \
192 off = 8; \
193 check_flags = PF_W|PF_X; \
194 } else \
195 continue; \
196 flags = EGET(phdr[i].p_flags); \
197 if (be_quiet && ((flags & check_flags) != check_flags)) \
198 continue; \
199 memcpy(ret+off, gnu_short_stack_flags(flags), 3); \
200 *found = 1; \
201 ++shown; \
202 } \
203 }
204 SHOW_PHDR(32)
205 SHOW_PHDR(64)
206 }
207
208 if (be_quiet && !shown)
209 return NULL;
210 else
211 return ret;
212 }
213 static char *scanelf_file_textrel(elfobj *elf, char *found_textrel)
214 {
215 static char ret[] = "TEXTREL";
216 unsigned long i;
217
218 if (!show_textrel && !show_textrels) return NULL;
219
220 if (elf->phdr) {
221 #define SHOW_TEXTREL(B) \
222 if (elf->elf_class == ELFCLASS ## B) { \
223 Elf ## B ## _Dyn *dyn; \
224 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
225 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
226 Elf ## B ## _Off offset; \
227 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
228 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
229 offset = EGET(phdr[i].p_offset); \
230 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
231 dyn = DYN ## B (elf->data + offset); \
232 while (EGET(dyn->d_tag) != DT_NULL) { \
233 if (EGET(dyn->d_tag) == DT_TEXTREL) { /*dyn->d_tag != DT_FLAGS)*/ \
234 *found_textrel = 1; \
235 /*if (dyn->d_un.d_val & DF_TEXTREL)*/ \
236 return (be_wewy_wewy_quiet ? NULL : ret); \
237 } \
238 ++dyn; \
239 } \
240 } }
241 SHOW_TEXTREL(32)
242 SHOW_TEXTREL(64)
243 }
244
245 if (be_quiet || be_wewy_wewy_quiet)
246 return NULL;
247 else
248 return (char *)" - ";
249 }
250 static char *scanelf_file_textrels(elfobj *elf, char *found_textrels, char *found_textrel)
251 {
252 unsigned long p, s, r, rmax;
253 void *symtab_void, *strtab_void;
254
255 if (!show_textrels) return NULL;
256
257 /* don't search for TEXTREL's if the ELF doesn't have any */
258 if (!*found_textrel) scanelf_file_textrel(elf, found_textrel);
259 if (!*found_textrel) return NULL;
260
261 scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
262
263 if (symtab_void && strtab_void && elf->phdr && elf->shdr) {
264 #define SHOW_TEXTRELS(B) \
265 if (elf->elf_class == ELFCLASS ## B) { \
266 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
267 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
268 Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \
269 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
270 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
271 Elf ## B ## _Rel *rel; \
272 Elf ## B ## _Rela *rela; \
273 /* search the section headers for relocations */ \
274 for (s = 0; s < EGET(ehdr->e_shnum); ++s) { \
275 uint32_t sh_type = EGET(shdr[s].sh_type); \
276 if (sh_type == SHT_REL) { \
277 rel = REL ## B (elf->data + EGET(shdr[s].sh_offset)); \
278 rela = NULL; \
279 rmax = EGET(shdr[s].sh_size) / sizeof(*rel); \
280 } else if (sh_type == SHT_RELA) { \
281 rel = NULL; \
282 rela = RELA ## B (elf->data + EGET(shdr[s].sh_offset)); \
283 rmax = EGET(shdr[s].sh_size) / sizeof(*rela); \
284 } else \
285 continue; \
286 /* search the program headers for PT_LOAD headers */ \
287 for (p = 0; p < EGET(ehdr->e_phnum); ++p) { \
288 Elf ## B ## _Addr vaddr; \
289 uint ## B ## _t memsz; \
290 if (EGET(phdr[p].p_type) != PT_LOAD) continue; \
291 if (EGET(phdr[p].p_flags) & PF_W) continue; \
292 vaddr = EGET(phdr[p].p_vaddr); \
293 memsz = EGET(phdr[p].p_memsz); \
294 /* now see if any of the relocs are in the PT_LOAD */ \
295 for (r = 0; r < rmax; ++r) { \
296 unsigned long sym_max; \
297 Elf ## B ## _Addr offset_tmp; \
298 Elf ## B ## _Sym *func; \
299 Elf ## B ## _Sym *sym; \
300 Elf ## B ## _Addr r_offset; \
301 uint ## B ## _t r_info; \
302 if (sh_type == SHT_REL) { \
303 r_offset = EGET(rel[r].r_offset); \
304 r_info = EGET(rel[r].r_info); \
305 } else { \
306 r_offset = EGET(rela[r].r_offset); \
307 r_info = EGET(rela[r].r_info); \
308 } \
309 /* make sure this relocation is inside of the .text */ \
310 if (r_offset < vaddr || r_offset >= vaddr + memsz) continue; \
311 *found_textrels = 1; \
312 /* locate this relocation symbol name */ \
313 sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \
314 sym_max = ELF ## B ## _R_SYM(r_info); \
315 if (sym_max * EGET(symtab->sh_entsize) < symtab->sh_size) \
316 sym += sym_max; \
317 else \
318 sym = NULL; \
319 sym_max = EGET(symtab->sh_size) / EGET(symtab->sh_entsize); \
320 /* show the raw details about this reloc */ \
321 printf("\tTEXTREL %s: ", elf->base_filename); \
322 if (sym && sym->st_name) \
323 printf("%s", (char*)(elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name))); \
324 else \
325 printf("(NULL: fake?)"); \
326 printf(" [0x%lX]", (unsigned long)r_offset); \
327 /* now try to find the closest symbol that this rel is probably in */ \
328 sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \
329 func = NULL; \
330 offset_tmp = 0; \
331 while (sym_max--) { \
332 if (EGET(sym->st_value) < r_offset && EGET(sym->st_value) > offset_tmp) { \
333 func = sym; \
334 offset_tmp = EGET(sym->st_value); \
335 } \
336 ++sym; \
337 } \
338 printf(" in "); \
339 if (func && func->st_name) \
340 printf("%s", (char*)(elf->data + EGET(strtab->sh_offset) + EGET(func->st_name))); \
341 else \
342 printf("(NULL: fake?)"); \
343 printf(" [0x%lX]\n", (unsigned long)offset_tmp); \
344 } \
345 } \
346 } }
347 SHOW_TEXTRELS(32)
348 SHOW_TEXTRELS(64)
349 }
350
351 return NULL;
352 }
353 static void scanelf_file_rpath(elfobj *elf, char *found_rpath, char **ret, size_t *ret_len)
354 {
355 unsigned long i, s;
356 char *rpath, *runpath, **r;
357 void *strtbl_void;
358
359 if (!show_rpath) return;
360
361 strtbl_void = elf_findsecbyname(elf, ".dynstr");
362 rpath = runpath = NULL;
363
364 if (elf->phdr && strtbl_void) {
365 #define SHOW_RPATH(B) \
366 if (elf->elf_class == ELFCLASS ## B) { \
367 Elf ## B ## _Dyn *dyn; \
368 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
369 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
370 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
371 Elf ## B ## _Off offset; \
372 Elf ## B ## _Xword word; \
373 /* Scan all the program headers */ \
374 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
375 /* Just scan dynamic headers */ \
376 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
377 offset = EGET(phdr[i].p_offset); \
378 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
379 /* Just scan dynamic RPATH/RUNPATH headers */ \
380 dyn = DYN ## B (elf->data + offset); \
381 while ((word=EGET(dyn->d_tag)) != DT_NULL) { \
382 if (word == DT_RPATH) { \
383 r = &rpath; \
384 } else if (word == DT_RUNPATH) { \
385 r = &runpath; \
386 } else { \
387 ++dyn; \
388 continue; \
389 } \
390 /* Verify the memory is somewhat sane */ \
391 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
392 if (offset < (Elf ## B ## _Off)elf->len) { \
393 if (*r) warn("ELF has multiple %s's !?", get_elfdtype(word)); \
394 *r = (char*)(elf->data + offset); \
395 /* If quiet, don't output paths in ld.so.conf */ \
396 if (be_quiet) { \
397 size_t len; \
398 char *start, *end; \
399 /* note that we only 'chop' off leading known paths. */ \
400 /* since *r is read-only memory, we can only move the ptr forward. */ \
401 start = *r; \
402 /* scan each path in : delimited list */ \
403 while (start) { \
404 end = strchr(start, ':'); \
405 len = (end ? abs(end - start) : strlen(start)); \
406 for (s = 0; ldpaths[s]; ++s) { \
407 if (!strncmp(ldpaths[s], start, len) && !ldpaths[s][len]) { \
408 *r = (end ? end + 1 : NULL); \
409 break; \
410 } \
411 } \
412 if (!*r || !ldpaths[s] || !end) \
413 start = NULL; \
414 else \
415 start = start + len + 1; \
416 } \
417 } \
418 if (*r) *found_rpath = 1; \
419 } \
420 ++dyn; \
421 } \
422 } }
423 SHOW_RPATH(32)
424 SHOW_RPATH(64)
425 }
426
427 if (be_wewy_wewy_quiet) return;
428
429 if (rpath && runpath) {
430 if (!strcmp(rpath, runpath)) {
431 xstrcat(ret, runpath, ret_len);
432 } else {
433 fprintf(stderr, "RPATH [%s] != RUNPATH [%s]\n", rpath, runpath);
434 xchrcat(ret, '{', ret_len);
435 xstrcat(ret, rpath, ret_len);
436 xchrcat(ret, ',', ret_len);
437 xstrcat(ret, runpath, ret_len);
438 xchrcat(ret, '}', ret_len);
439 }
440 } else if (rpath || runpath)
441 xstrcat(ret, (runpath ? runpath : rpath), ret_len);
442 else if (!be_quiet)
443 xstrcat(ret, " - ", ret_len);
444 }
445 static char *scanelf_file_needed_lib(elfobj *elf, char *found_needed, char *found_lib, int op, char **ret, size_t *ret_len)
446 {
447 unsigned long i;
448 char *needed;
449 void *strtbl_void;
450
451 if ((op==0 && !show_needed) || (op==1 && !find_lib)) return NULL;
452
453 strtbl_void = elf_findsecbyname(elf, ".dynstr");
454
455 if (elf->phdr && strtbl_void) {
456 #define SHOW_NEEDED(B) \
457 if (elf->elf_class == ELFCLASS ## B) { \
458 Elf ## B ## _Dyn *dyn; \
459 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
460 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
461 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
462 Elf ## B ## _Off offset; \
463 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
464 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
465 offset = EGET(phdr[i].p_offset); \
466 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
467 dyn = DYN ## B (elf->data + offset); \
468 while (EGET(dyn->d_tag) != DT_NULL) { \
469 if (EGET(dyn->d_tag) == DT_NEEDED) { \
470 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
471 if (offset >= (Elf ## B ## _Off)elf->len) { \
472 ++dyn; \
473 continue; \
474 } \
475 needed = (char*)(elf->data + offset); \
476 if (op == 0) { \
477 if (!be_wewy_wewy_quiet) { \
478 if (*found_needed) xchrcat(ret, ',', ret_len); \
479 xstrcat(ret, needed, ret_len); \
480 } \
481 *found_needed = 1; \
482 } else { \
483 if (strcmp(find_lib, needed)) return NULL; \
484 *found_lib = 1; \
485 return (be_wewy_wewy_quiet ? NULL : find_lib); \
486 } \
487 } \
488 ++dyn; \
489 } \
490 } }
491 SHOW_NEEDED(32)
492 SHOW_NEEDED(64)
493 }
494
495 return NULL;
496 }
497 static char *scanelf_file_interp(elfobj *elf, char *found_interp)
498 {
499 void *strtbl_void;
500
501 if (!show_interp) return NULL;
502
503 strtbl_void = elf_findsecbyname(elf, ".interp");
504
505 if (strtbl_void) {
506 #define SHOW_INTERP(B) \
507 if (elf->elf_class == ELFCLASS ## B) { \
508 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
509 *found_interp = 1; \
510 return (be_wewy_wewy_quiet ? NULL : elf->data + EGET(strtbl->sh_offset)); \
511 }
512 SHOW_INTERP(32)
513 SHOW_INTERP(64)
514 }
515 return NULL;
516 }
517 static char *scanelf_file_bind(elfobj *elf, char *found_bind)
518 {
519 unsigned long i;
520 struct stat s;
521
522 if (!show_bind) return NULL;
523 if (!elf->phdr) return NULL;
524
525 #define SHOW_BIND(B) \
526 if (elf->elf_class == ELFCLASS ## B) { \
527 Elf ## B ## _Dyn *dyn; \
528 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
529 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
530 Elf ## B ## _Off offset; \
531 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
532 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
533 offset = EGET(phdr[i].p_offset); \
534 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
535 dyn = DYN ## B (elf->data + offset); \
536 while (EGET(dyn->d_tag) != DT_NULL) { \
537 if (EGET(dyn->d_tag) == DT_BIND_NOW || \
538 (EGET(dyn->d_tag) == DT_FLAGS && EGET(dyn->d_un.d_val) & DF_BIND_NOW)) \
539 { \
540 if (be_quiet) return NULL; \
541 *found_bind = 1; \
542 return (char *)(be_wewy_wewy_quiet ? NULL : "NOW"); \
543 } \
544 ++dyn; \
545 } \
546 } \
547 }
548 SHOW_BIND(32)
549 SHOW_BIND(64)
550
551 if (be_wewy_wewy_quiet) return NULL;
552
553 if (be_quiet && !fstat(elf->fd, &s) && !(s.st_mode & S_ISUID || s.st_mode & S_ISGID)) {
554 return NULL;
555 } else {
556 *found_bind = 1;
557 return (char *) "LAZY";
558 }
559 }
560 static char *scanelf_file_sym(elfobj *elf, char *found_sym)
561 {
562 unsigned long i;
563 void *symtab_void, *strtab_void;
564
565 if (!find_sym) return NULL;
566
567 scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
568
569 if (symtab_void && strtab_void) {
570 #define FIND_SYM(B) \
571 if (elf->elf_class == ELFCLASS ## B) { \
572 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
573 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
574 Elf ## B ## _Sym *sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \
575 unsigned long cnt = EGET(symtab->sh_size) / EGET(symtab->sh_entsize); \
576 char *symname; \
577 for (i = 0; i < cnt; ++i) { \
578 if (sym->st_name) { \
579 symname = (char *)(elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name)); \
580 if (*find_sym == '*') { \
581 printf("%s(%s) %5lX %15s %s\n", \
582 ((*found_sym == 0) ? "\n\t" : "\t"), \
583 elf->base_filename, \
584 (long)sym->st_size, \
585 (char *)get_elfstttype(sym->st_info), \
586 symname); \
587 *found_sym = 1; \
588 } else if ((strcmp(find_sym, symname) == 0) || \
589 (strcmp(symname, versioned_symname) == 0)) \
590 (*found_sym)++; \
591 } \
592 ++sym; \
593 } }
594 FIND_SYM(32)
595 FIND_SYM(64)
596 }
597
598 if (be_wewy_wewy_quiet) return NULL;
599
600 if (*find_sym != '*' && *found_sym)
601 return find_sym;
602 if (be_quiet)
603 return NULL;
604 else
605 return (char *)" - ";
606 }
607 /* scan an elf file and show all the fun stuff */
608 #define prints(str) write(fileno(stdout), str, strlen(str))
609 static void scanelf_file(const char *filename)
610 {
611 unsigned long i;
612 char found_pax, found_phdr, found_relro, found_load, found_textrel,
613 found_rpath, found_needed, found_interp, found_bind,
614 found_sym, found_lib, found_file, found_textrels;
615 elfobj *elf;
616 struct stat st;
617 static char *out_buffer = NULL;
618 static size_t out_len;
619
620 /* make sure 'filename' exists */
621 if (lstat(filename, &st) == -1) {
622 if (be_verbose > 2) printf("%s: does not exist\n", filename);
623 return;
624 }
625 /* always handle regular files and handle symlinked files if no -y */
626 if (S_ISLNK(st.st_mode)) {
627 if (!scan_symlink) return;
628 stat(filename, &st);
629 }
630 if (!S_ISREG(st.st_mode)) {
631 if (be_verbose > 2) printf("%s: skipping non-file\n", filename);
632 return;
633 }
634
635 found_pax = found_phdr = found_relro = found_load = found_textrel = \
636 found_rpath = found_needed = found_interp = found_bind = \
637 found_sym = found_lib = found_file = found_textrels = 0;
638
639 /* verify this is real ELF */
640 if ((elf = readelf(filename)) == NULL) {
641 if (be_verbose > 2) printf("%s: not an ELF\n", filename);
642 return;
643 }
644
645 if (be_verbose > 1)
646 printf("%s: scanning file {%s,%s}\n", filename,
647 get_elfeitype(EI_CLASS, elf->elf_class),
648 get_elfeitype(EI_DATA, elf->data[EI_DATA]));
649 else if (be_verbose)
650 printf("%s: scanning file\n", filename);
651
652 /* init output buffer */
653 if (!out_buffer) {
654 out_len = sizeof(char) * 80;
655 out_buffer = (char*)xmalloc(out_len);
656 }
657 *out_buffer = '\0';
658
659 /* show the header */
660 if (!be_quiet && show_banner) {
661 for (i = 0; out_format[i]; ++i) {
662 if (!IS_MODIFIER(out_format[i])) continue;
663
664 switch (out_format[++i]) {
665 case '%': break;
666 case '#': break;
667 case 'F':
668 case 'p':
669 case 'f': prints("FILE "); found_file = 1; break;
670 case 'o': prints(" TYPE "); break;
671 case 'x': prints(" PAX "); break;
672 case 'e': prints("STK/REL/PTL "); break;
673 case 't': prints("TEXTREL "); break;
674 case 'r': prints("RPATH "); break;
675 case 'n': prints("NEEDED "); break;
676 case 'i': prints("INTERP "); break;
677 case 'b': prints("BIND "); break;
678 case 's': prints("SYM "); break;
679 case 'N': prints("LIB "); break;
680 case 'T': prints("TEXTRELS "); break;
681 default: warnf("'%c' has no title ?", out_format[i]);
682 }
683 }
684 if (!found_file) prints("FILE ");
685 prints("\n");
686 found_file = 0;
687 show_banner = 0;
688 }
689
690 /* dump all the good stuff */
691 for (i = 0; out_format[i]; ++i) {
692 const char *out;
693 const char *tmp;
694
695 /* make sure we trim leading spaces in quiet mode */
696 if (be_quiet && *out_buffer == ' ' && !out_buffer[1])
697 *out_buffer = '\0';
698
699 if (!IS_MODIFIER(out_format[i])) {
700 xchrcat(&out_buffer, out_format[i], &out_len);
701 continue;
702 }
703
704 out = NULL;
705 be_wewy_wewy_quiet = (out_format[i] == '#');
706 switch (out_format[++i]) {
707 case '%':
708 case '#':
709 xchrcat(&out_buffer, out_format[i], &out_len); break;
710 case 'F':
711 found_file = 1;
712 if (be_wewy_wewy_quiet) break;
713 xstrcat(&out_buffer, filename, &out_len);
714 break;
715 case 'p':
716 found_file = 1;
717 if (be_wewy_wewy_quiet) break;
718 tmp = filename;
719 if (search_path) {
720 ssize_t len_search = strlen(search_path);
721 ssize_t len_file = strlen(filename);
722 if (!strncmp(filename, search_path, len_search) && \
723 len_file > len_search)
724 tmp += len_search;
725 if (*tmp == '/' && search_path[len_search-1] == '/') tmp++;
726 }
727 xstrcat(&out_buffer, tmp, &out_len);
728 break;
729 case 'f':
730 found_file = 1;
731 if (be_wewy_wewy_quiet) break;
732 tmp = strrchr(filename, '/');
733 tmp = (tmp == NULL ? filename : tmp+1);
734 xstrcat(&out_buffer, tmp, &out_len);
735 break;
736 case 'o': out = get_elfetype(elf); break;
737 case 'x': out = scanelf_file_pax(elf, &found_pax); break;
738 case 'e': out = scanelf_file_phdr(elf, &found_phdr, &found_relro, &found_load); break;
739 case 't': out = scanelf_file_textrel(elf, &found_textrel); break;
740 case 'T': out = scanelf_file_textrels(elf, &found_textrels, &found_textrel); break;
741 case 'r': scanelf_file_rpath(elf, &found_rpath, &out_buffer, &out_len); break;
742 case 'n':
743 case 'N': out = scanelf_file_needed_lib(elf, &found_needed, &found_lib, (out_format[i]=='N'), &out_buffer, &out_len); break;
744 case 'i': out = scanelf_file_interp(elf, &found_interp); break;
745 case 'b': out = scanelf_file_bind(elf, &found_bind); break;
746 case 's': out = scanelf_file_sym(elf, &found_sym); break;
747 default: warnf("'%c' has no scan code?", out_format[i]);
748 }
749 if (out) xstrcat(&out_buffer, out, &out_len);
750 }
751
752 #define FOUND_SOMETHING() \
753 (found_pax || found_phdr || found_relro || found_load || found_textrel || \
754 found_rpath || found_needed || found_interp || found_bind || \
755 found_sym || found_lib || found_textrels)
756
757 if (!found_file && (!be_quiet || (be_quiet && FOUND_SOMETHING()))) {
758 xchrcat(&out_buffer, ' ', &out_len);
759 xstrcat(&out_buffer, filename, &out_len);
760 }
761 if (!be_quiet || (be_quiet && FOUND_SOMETHING())) {
762 puts(out_buffer);
763 fflush(stdout);
764 }
765
766 unreadelf(elf);
767 }
768
769 /* scan a directory for ET_EXEC files and print when we find one */
770 static void scanelf_dir(const char *path)
771 {
772 register DIR *dir;
773 register struct dirent *dentry;
774 struct stat st_top, st;
775 char buf[_POSIX_PATH_MAX];
776 size_t pathlen = 0, len = 0;
777
778 /* make sure path exists */
779 if (lstat(path, &st_top) == -1) {
780 if (be_verbose > 2) printf("%s: does not exist\n", path);
781 return;
782 }
783
784 /* ok, if it isn't a directory, assume we can open it */
785 if (!S_ISDIR(st_top.st_mode)) {
786 scanelf_file(path);
787 return;
788 }
789
790 /* now scan the dir looking for fun stuff */
791 if ((dir = opendir(path)) == NULL) {
792 warnf("could not opendir %s: %s", path, strerror(errno));
793 return;
794 }
795 if (be_verbose) printf("%s: scanning dir\n", path);
796
797 pathlen = strlen(path);
798 while ((dentry = readdir(dir))) {
799 if (!strcmp(dentry->d_name, ".") || !strcmp(dentry->d_name, ".."))
800 continue;
801 len = (pathlen + 1 + strlen(dentry->d_name) + 1);
802 if (len >= sizeof(buf)) {
803 warnf("Skipping '%s': len > sizeof(buf); %lu > %lu\n", path,
804 (unsigned long)len, (unsigned long)sizeof(buf));
805 continue;
806 }
807 sprintf(buf, "%s/%s", path, dentry->d_name);
808 if (lstat(buf, &st) != -1) {
809 if (S_ISREG(st.st_mode))
810 scanelf_file(buf);
811 else if (dir_recurse && S_ISDIR(st.st_mode)) {
812 if (dir_crossmount || (st_top.st_dev == st.st_dev))
813 scanelf_dir(buf);
814 }
815 }
816 }
817 closedir(dir);
818 }
819
820 static int scanelf_from_file(char *filename)
821 {
822 FILE *fp = NULL;
823 char *p;
824 char path[_POSIX_PATH_MAX];
825
826 if (((strcmp(filename, "-")) == 0) && (ttyname(0) == NULL))
827 fp = stdin;
828 else if ((fp = fopen(filename, "r")) == NULL)
829 return 1;
830
831 while ((fgets(path, _POSIX_PATH_MAX, fp)) != NULL) {
832 if ((p = strchr(path, '\n')) != NULL)
833 *p = 0;
834 search_path = path;
835 scanelf_dir(path);
836 }
837 if (fp != stdin)
838 fclose(fp);
839 return 0;
840 }
841
842 static void load_ld_so_conf()
843 {
844 FILE *fp = NULL;
845 char *p;
846 char path[_POSIX_PATH_MAX];
847 int i = 0;
848
849 if ((fp = fopen("/etc/ld.so.conf", "r")) == NULL)
850 return;
851
852 while ((fgets(path, _POSIX_PATH_MAX, fp)) != NULL) {
853 if (*path != '/')
854 continue;
855
856 if ((p = strrchr(path, '\r')) != NULL)
857 *p = 0;
858 if ((p = strchr(path, '\n')) != NULL)
859 *p = 0;
860
861 ldpaths[i++] = xstrdup(path);
862
863 if (i + 1 == sizeof(ldpaths) / sizeof(*ldpaths))
864 break;
865 }
866 ldpaths[i] = NULL;
867
868 fclose(fp);
869 }
870
871 /* scan /etc/ld.so.conf for paths */
872 static void scanelf_ldpath()
873 {
874 char scan_l, scan_ul, scan_ull;
875 int i = 0;
876
877 if (!ldpaths[0])
878 err("Unable to load any paths from ld.so.conf");
879
880 scan_l = scan_ul = scan_ull = 0;
881
882 while (ldpaths[i]) {
883 if (!scan_l && !strcmp(ldpaths[i], "/lib")) scan_l = 1;
884 if (!scan_ul && !strcmp(ldpaths[i], "/usr/lib")) scan_ul = 1;
885 if (!scan_ull && !strcmp(ldpaths[i], "/usr/local/lib")) scan_ull = 1;
886 scanelf_dir(ldpaths[i]);
887 ++i;
888 }
889
890 if (!scan_l) scanelf_dir("/lib");
891 if (!scan_ul) scanelf_dir("/usr/lib");
892 if (!scan_ull) scanelf_dir("/usr/local/lib");
893 }
894
895 /* scan env PATH for paths */
896 static void scanelf_envpath()
897 {
898 char *path, *p;
899
900 path = getenv("PATH");
901 if (!path)
902 err("PATH is not set in your env !");
903 path = xstrdup(path);
904
905 while ((p = strrchr(path, ':')) != NULL) {
906 scanelf_dir(p + 1);
907 *p = 0;
908 }
909
910 free(path);
911 }
912
913
914
915 /* usage / invocation handling functions */
916 #define PARSE_FLAGS "plRmyxetrnibs:N:TaqvF:f:o:BhV"
917 #define a_argument required_argument
918 static struct option const long_opts[] = {
919 {"path", no_argument, NULL, 'p'},
920 {"ldpath", no_argument, NULL, 'l'},
921 {"recursive", no_argument, NULL, 'R'},
922 {"mount", no_argument, NULL, 'm'},
923 {"symlink", no_argument, NULL, 'y'},
924 {"pax", no_argument, NULL, 'x'},
925 {"header", no_argument, NULL, 'e'},
926 {"textrel", no_argument, NULL, 't'},
927 {"rpath", no_argument, NULL, 'r'},
928 {"needed", no_argument, NULL, 'n'},
929 {"interp", no_argument, NULL, 'i'},
930 {"bind", no_argument, NULL, 'b'},
931 {"symbol", a_argument, NULL, 's'},
932 {"lib", a_argument, NULL, 'N'},
933 {"textrels", no_argument, NULL, 'T'},
934 {"all", no_argument, NULL, 'a'},
935 {"quiet", no_argument, NULL, 'q'},
936 {"verbose", no_argument, NULL, 'v'},
937 {"format", a_argument, NULL, 'F'},
938 {"from", a_argument, NULL, 'f'},
939 {"file", a_argument, NULL, 'o'},
940 {"nobanner", no_argument, NULL, 'B'},
941 {"help", no_argument, NULL, 'h'},
942 {"version", no_argument, NULL, 'V'},
943 {NULL, no_argument, NULL, 0x0}
944 };
945
946 static const char *opts_help[] = {
947 "Scan all directories in PATH environment",
948 "Scan all directories in /etc/ld.so.conf",
949 "Scan directories recursively",
950 "Don't recursively cross mount points",
951 "Don't scan symlinks\n",
952 "Print PaX markings",
953 "Print GNU_STACK/PT_LOAD markings",
954 "Print TEXTREL information",
955 "Print RPATH information",
956 "Print NEEDED information",
957 "Print INTERP information",
958 "Print BIND information",
959 "Find a specified symbol",
960 "Find a specified library",
961 "Locate cause of TEXTREL",
962 "Print all scanned info (-x -e -t -r -n -i -b)\n",
963 "Only output 'bad' things",
964 "Be verbose (can be specified more than once)",
965 "Use specified format for output",
966 "Read input stream from a filename",
967 "Write output stream to a filename",
968 "Don't display the header",
969 "Print this help and exit",
970 "Print version and exit",
971 NULL
972 };
973
974 /* display usage and exit */
975 static void usage(int status)
976 {
977 unsigned long i;
978 printf("* Scan ELF binaries for stuff\n\n"
979 "Usage: %s [options] <dir1/file1> [dir2 dirN fileN ...]\n\n", argv0);
980 printf("Options: -[%s]\n", PARSE_FLAGS);
981 for (i = 0; long_opts[i].name; ++i)
982 if (long_opts[i].has_arg == no_argument)
983 printf(" -%c, --%-13s* %s\n", long_opts[i].val,
984 long_opts[i].name, opts_help[i]);
985 else
986 printf(" -%c, --%-6s <arg> * %s\n", long_opts[i].val,
987 long_opts[i].name, opts_help[i]);
988
989 if (status != EXIT_SUCCESS)
990 exit(status);
991
992 puts("\nThe format modifiers for the -F option are:");
993 puts(" F Filename \tx PaX Flags \te STACK/RELRO");
994 puts(" t TEXTREL \tr RPATH \tn NEEDED");
995 puts(" i INTERP \tb BIND \ts symbol");
996 puts(" N library \to Type \tT TEXTRELs");
997 puts(" p filename (with search path removed)");
998 puts(" f base filename");
999 puts("Prefix each modifier with '%' (verbose) or '#' (silent)");
1000
1001 exit(status);
1002 }
1003
1004 /* parse command line arguments and preform needed actions */
1005 static void parseargs(int argc, char *argv[])
1006 {
1007 int i;
1008 char *from_file = NULL;
1009
1010 opterr = 0;
1011 while ((i=getopt_long(argc, argv, PARSE_FLAGS, long_opts, NULL)) != -1) {
1012 switch (i) {
1013
1014 case 'V':
1015 printf("%s compiled %s\n%s\n"
1016 "%s written for Gentoo Linux by <solar and vapier @ gentoo.org>\n",
1017 __FILE__, __DATE__, rcsid, argv0);
1018 exit(EXIT_SUCCESS);
1019 break;
1020 case 'h': usage(EXIT_SUCCESS); break;
1021 case 'f':
1022 if (from_file) err("Don't specify -f twice");
1023 from_file = xstrdup(optarg);
1024 break;
1025 case 'o': {
1026 FILE *fp = NULL;
1027 if ((fp = freopen(optarg, "w", stdout)) == NULL)
1028 err("Could not open output stream '%s': %s", optarg, strerror(errno));
1029 SET_STDOUT(fp);
1030 break;
1031 }
1032
1033 case 's': {
1034 size_t len;
1035 if (find_sym) err("Don't specify -s twice");
1036 find_sym = xstrdup(optarg);
1037 len = strlen(find_sym) + 1;
1038 versioned_symname = (char*)xmalloc(sizeof(char) * (len+1));
1039 sprintf(versioned_symname, "%s@", find_sym);
1040 break;
1041 }
1042 case 'N': {
1043 if (find_lib) err("Don't specify -N twice");
1044 find_lib = xstrdup(optarg);
1045 break;
1046 }
1047
1048 case 'F': {
1049 if (out_format) err("Don't specify -F twice");
1050 out_format = xstrdup(optarg);
1051 break;
1052 }
1053
1054 case 'y': scan_symlink = 0; break;
1055 case 'B': show_banner = 0; break;
1056 case 'l': scan_ldpath = 1; break;
1057 case 'p': scan_envpath = 1; break;
1058 case 'R': dir_recurse = 1; break;
1059 case 'm': dir_crossmount = 0; break;
1060 case 'x': show_pax = 1; break;
1061 case 'e': show_phdr = 1; break;
1062 case 't': show_textrel = 1; break;
1063 case 'r': show_rpath = 1; break;
1064 case 'n': show_needed = 1; break;
1065 case 'i': show_interp = 1; break;
1066 case 'b': show_bind = 1; break;
1067 case 'T': show_textrels = 1; break;
1068 case 'q': be_quiet = 1; break;
1069 case 'v': be_verbose = (be_verbose % 20) + 1; break;
1070 case 'a': show_pax = show_phdr = show_textrel = show_rpath = \
1071 show_needed = show_interp = show_bind = 1; break;
1072
1073 case ':':
1074 err("Option missing parameter\n");
1075 case '?':
1076 err("Unknown option\n");
1077 default:
1078 err("Unhandled option '%c'", i);
1079 }
1080 }
1081
1082 /* let the format option override all other options */
1083 if (out_format) {
1084 show_pax = show_phdr = show_textrel = show_rpath = \
1085 show_needed = show_interp = show_bind = show_textrels = 0;
1086 for (i = 0; out_format[i]; ++i) {
1087 if (!IS_MODIFIER(out_format[i])) continue;
1088
1089 switch (out_format[++i]) {
1090 case '%': break;
1091 case '#': break;
1092 case 'F': break;
1093 case 'p': break;
1094 case 'f': break;
1095 case 's': break;
1096 case 'N': break;
1097 case 'o': break;
1098 case 'x': show_pax = 1; break;
1099 case 'e': show_phdr = 1; break;
1100 case 't': show_textrel = 1; break;
1101 case 'r': show_rpath = 1; break;
1102 case 'n': show_needed = 1; break;
1103 case 'i': show_interp = 1; break;
1104 case 'b': show_bind = 1; break;
1105 case 'T': show_textrels = 1; break;
1106 default:
1107 err("Invalid format specifier '%c' (byte %i)",
1108 out_format[i], i+1);
1109 }
1110 }
1111
1112 /* construct our default format */
1113 } else {
1114 size_t fmt_len = 30;
1115 out_format = (char*)xmalloc(sizeof(char) * fmt_len);
1116 if (!be_quiet) xstrcat(&out_format, "%o ", &fmt_len);
1117 if (show_pax) xstrcat(&out_format, "%x ", &fmt_len);
1118 if (show_phdr) xstrcat(&out_format, "%e ", &fmt_len);
1119 if (show_textrel) xstrcat(&out_format, "%t ", &fmt_len);
1120 if (show_rpath) xstrcat(&out_format, "%r ", &fmt_len);
1121 if (show_needed) xstrcat(&out_format, "%n ", &fmt_len);
1122 if (show_interp) xstrcat(&out_format, "%i ", &fmt_len);
1123 if (show_bind) xstrcat(&out_format, "%b ", &fmt_len);
1124 if (show_textrels) xstrcat(&out_format, "%T ", &fmt_len);
1125 if (find_sym) xstrcat(&out_format, "%s ", &fmt_len);
1126 if (find_lib) xstrcat(&out_format, "%N ", &fmt_len);
1127 if (!be_quiet) xstrcat(&out_format, "%F ", &fmt_len);
1128 }
1129 if (be_verbose > 2) printf("Format: %s\n", out_format);
1130
1131 /* now lets actually do the scanning */
1132 if (scan_ldpath || (show_rpath && be_quiet))
1133 load_ld_so_conf();
1134 if (scan_ldpath) scanelf_ldpath();
1135 if (scan_envpath) scanelf_envpath();
1136 if (from_file) {
1137 scanelf_from_file(from_file);
1138 free(from_file);
1139 from_file = *argv;
1140 }
1141 if (optind == argc && !scan_ldpath && !scan_envpath && !from_file)
1142 err("Nothing to scan !?");
1143 while (optind < argc) {
1144 search_path = argv[optind++];
1145 scanelf_dir(search_path);
1146 }
1147
1148 /* clean up */
1149 if (find_sym) {
1150 free(find_sym);
1151 free(versioned_symname);
1152 }
1153 if (find_lib) free(find_lib);
1154 if (out_format) free(out_format);
1155 for (i = 0; ldpaths[i]; ++i)
1156 free(ldpaths[i]);
1157 }
1158
1159
1160
1161 /* utility funcs */
1162 static char *xstrdup(const char *s)
1163 {
1164 char *ret = strdup(s);
1165 if (!ret) err("Could not strdup(): %s", strerror(errno));
1166 return ret;
1167 }
1168
1169 static void *xmalloc(size_t size)
1170 {
1171 void *ret = malloc(size);
1172 if (!ret) err("Could not malloc() %li bytes", (unsigned long)size);
1173 return ret;
1174 }
1175
1176 static void xstrcat(char **dst, const char *src, size_t *curr_len)
1177 {
1178 size_t new_len;
1179
1180 new_len = strlen(*dst) + strlen(src);
1181 if (*curr_len <= new_len) {
1182 *curr_len = new_len + (*curr_len / 2);
1183 *dst = realloc(*dst, *curr_len);
1184 if (!*dst)
1185 err("could not realloc %li bytes", (unsigned long)*curr_len);
1186 }
1187
1188 strcat(*dst, src);
1189 }
1190
1191 static inline void xchrcat(char **dst, const char append, size_t *curr_len)
1192 {
1193 static char my_app[2];
1194 my_app[0] = append;
1195 my_app[1] = '\0';
1196 xstrcat(dst, my_app, curr_len);
1197 }
1198
1199
1200
1201 int main(int argc, char *argv[])
1202 {
1203 if (argc < 2)
1204 usage(EXIT_FAILURE);
1205 parseargs(argc, argv);
1206 fclose(stdout);
1207 #ifdef __BOUNDS_CHECKING_ON
1208 warn("The calls to add/delete heap should be off by 1 due to the out_buffer not being freed in scanelf_file()");
1209 #endif
1210 return EXIT_SUCCESS;
1211 }

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