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

Contents of /pax-utils/scanelf.c

Parent Directory Parent Directory | Revision Log Revision Log


Revision 1.67 - (show annotations) (download) (as text)
Fri Jun 3 02:56:18 2005 UTC (8 years, 10 months ago) by vapier
Branch: MAIN
Changes since 1.66: +8 -2 lines
File MIME type: text/x-csrc
fall back to runtime section headers if the debug ones have been stripped

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 1.66 2005/06/01 22:37:38 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 1.66 2005/06/01 22:37:38 vapier Exp $";
39 #define argv0 "scanelf"
40
41
42
43 /* prototypes */
44 static void scanelf_file(const char *filename);
45 static void scanelf_dir(const char *path);
46 static void scanelf_ldpath();
47 static void scanelf_envpath();
48 static void usage(int status);
49 static void parseargs(int argc, char *argv[]);
50 static char *xstrdup(const char *s);
51 static void *xmalloc(size_t size);
52 static void xstrcat(char **dst, const char *src, size_t *curr_len);
53 static inline void xchrcat(char **dst, const char append, size_t *curr_len);
54
55 /* variables to control behavior */
56 static char *ldpaths[256];
57 static char scan_ldpath = 0;
58 static char scan_envpath = 0;
59 static char scan_symlink = 1;
60 static char dir_recurse = 0;
61 static char dir_crossmount = 1;
62 static char show_pax = 0;
63 static char show_stack = 0;
64 static char show_textrel = 0;
65 static char show_rpath = 0;
66 static char show_needed = 0;
67 static char show_interp = 0;
68 static char show_bind = 0;
69 static char show_banner = 1;
70 static char be_quiet = 0;
71 static char be_verbose = 0;
72 static char *find_sym = NULL, *versioned_symname = NULL;
73 static char *out_format = NULL;
74 static char *search_path = NULL;
75
76
77 /* sub-funcs for scanelf_file() */
78 static char *scanelf_file_pax(elfobj *elf, char *found_pax)
79 {
80 static char *paxflags;
81 static char ret[7];
82 unsigned long i, shown;
83
84
85 if (!show_pax) return NULL;
86
87 shown = 0;
88 memset(&ret, 0, sizeof(ret));
89
90 if (elf->phdr) {
91 #define SHOW_PAX(B) \
92 if (elf->elf_class == ELFCLASS ## B) { \
93 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
94 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
95 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
96 if (EGET(phdr[i].p_type) != PT_PAX_FLAGS) \
97 continue; \
98 if (be_quiet && (EGET(phdr[i].p_flags) == 10240)) \
99 continue; \
100 memcpy(ret, pax_short_pf_flags(EGET(phdr[i].p_flags)), 6); \
101 *found_pax = 1; \
102 ++shown; \
103 break; \
104 } \
105 }
106 SHOW_PAX(32)
107 SHOW_PAX(64)
108 }
109
110 /* fall back to EI_PAX if no PT_PAX was found */
111 if (!*ret) {
112 paxflags = pax_short_hf_flags(EI_PAX_FLAGS(elf));
113 if (!be_quiet || (be_quiet && EI_PAX_FLAGS(elf))) {
114 *found_pax = 1;
115 return paxflags;
116 }
117 strncpy(ret, paxflags, sizeof(ret));
118 // ++shown;
119 }
120
121 if (be_quiet && !shown)
122 return NULL;
123 return ret;
124
125 }
126 static char *scanelf_file_stack(elfobj *elf, char *found_stack, char *found_relro)
127 {
128 static char ret[8] = "--- ---";
129 char *found;
130 unsigned long i, off, shown;
131
132 if (!show_stack) return NULL;
133
134 shown = 0;
135
136 if (elf->phdr) {
137 #define SHOW_STACK(B) \
138 if (elf->elf_class == ELFCLASS ## B) { \
139 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
140 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
141 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
142 if (EGET(phdr[i].p_type) == PT_GNU_STACK) { \
143 found = found_stack; \
144 off = 0; \
145 } else if (EGET(phdr[i].p_type) == PT_GNU_RELRO) { \
146 found = found_relro; \
147 off = 4; \
148 } else \
149 continue; \
150 if (be_quiet && !(EGET(phdr[i].p_flags) & PF_X)) \
151 continue; \
152 memcpy(ret+off, gnu_short_stack_flags(EGET(phdr[i].p_flags)), 3); \
153 *found = 1; \
154 ++shown; \
155 } \
156 }
157 SHOW_STACK(32)
158 SHOW_STACK(64)
159 }
160
161 if (be_quiet && !shown)
162 return NULL;
163 else
164 return ret;
165 }
166 static char *scanelf_file_textrel(elfobj *elf, char *found_textrel)
167 {
168 static char *ret = "TEXTREL";
169 unsigned long i;
170
171 if (!show_textrel) return NULL;
172
173 if (elf->phdr) {
174 #define SHOW_TEXTREL(B) \
175 if (elf->elf_class == ELFCLASS ## B) { \
176 Elf ## B ## _Dyn *dyn; \
177 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
178 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
179 Elf ## B ## _Off offset; \
180 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
181 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
182 offset = EGET(phdr[i].p_offset); \
183 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
184 dyn = DYN ## B (elf->data + offset); \
185 while (EGET(dyn->d_tag) != DT_NULL) { \
186 if (EGET(dyn->d_tag) == DT_TEXTREL) { /*dyn->d_tag != DT_FLAGS)*/ \
187 *found_textrel = 1; \
188 /*if (dyn->d_un.d_val & DF_TEXTREL)*/ \
189 return ret; \
190 } \
191 ++dyn; \
192 } \
193 } }
194 SHOW_TEXTREL(32)
195 SHOW_TEXTREL(64)
196 }
197
198 if (be_quiet)
199 return NULL;
200 else
201 return " - ";
202 }
203 static void scanelf_file_rpath(elfobj *elf, char *found_rpath, char **ret, size_t *ret_len)
204 {
205 /* TODO: when checking RPATH entries, check each subpath (between :) in ld.so.conf */
206 unsigned long i, s;
207 char *rpath, *runpath, **r;
208 void *strtbl_void;
209
210 if (!show_rpath) return;
211
212 strtbl_void = elf_findsecbyname(elf, ".dynstr");
213 rpath = runpath = NULL;
214
215 if (elf->phdr && strtbl_void) {
216 #define SHOW_RPATH(B) \
217 if (elf->elf_class == ELFCLASS ## B) { \
218 Elf ## B ## _Dyn *dyn; \
219 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
220 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
221 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
222 Elf ## B ## _Off offset; \
223 Elf ## B ## _Xword word; \
224 /* Scan all the program headers */ \
225 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
226 /* Just scan dynamic headers */ \
227 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
228 offset = EGET(phdr[i].p_offset); \
229 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
230 /* Just scan dynamic RPATH/RUNPATH headers */ \
231 dyn = DYN ## B (elf->data + offset); \
232 while ((word=EGET(dyn->d_tag)) != DT_NULL) { \
233 if (word == DT_RPATH) { \
234 r = &rpath; \
235 } else if (word == DT_RUNPATH) { \
236 r = &runpath; \
237 } else { \
238 ++dyn; \
239 continue; \
240 } \
241 /* Verify the memory is somewhat sane */ \
242 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
243 if (offset < elf->len) { \
244 if (*r) warn("ELF has multiple %s's !?", get_elfdtype(word)); \
245 *r = (char*)(elf->data + offset); \
246 /* If quiet, don't output paths in ld.so.conf */ \
247 if (be_quiet) \
248 for (s = 0; ldpaths[s]; ++s) \
249 if (!strcmp(ldpaths[s], *r)) { \
250 *r = NULL; \
251 break; \
252 } \
253 if (*r) *found_rpath = 1; \
254 } \
255 ++dyn; \
256 } \
257 } }
258 SHOW_RPATH(32)
259 SHOW_RPATH(64)
260 }
261
262 if (rpath && runpath) {
263 if (!strcmp(rpath, runpath)) {
264 xstrcat(ret, runpath, ret_len);
265 } else {
266 fprintf(stderr, "RPATH [%s] != RUNPATH [%s]\n", rpath, runpath);
267 xchrcat(ret, '{', ret_len);
268 xstrcat(ret, rpath, ret_len);
269 xchrcat(ret, ',', ret_len);
270 xstrcat(ret, runpath, ret_len);
271 xchrcat(ret, '}', ret_len);
272 }
273 } else if (rpath || runpath)
274 xstrcat(ret, (runpath ? runpath : rpath), ret_len);
275 else if (!be_quiet)
276 xstrcat(ret, " - ", ret_len);
277 }
278 static void scanelf_file_needed(elfobj *elf, char *found_needed, char **ret, size_t *ret_len)
279 {
280 unsigned long i;
281 char *needed;
282 void *strtbl_void;
283
284 if (!show_needed) return;
285
286 strtbl_void = elf_findsecbyname(elf, ".dynstr");
287
288 if (elf->phdr && strtbl_void) {
289 #define SHOW_NEEDED(B) \
290 if (elf->elf_class == ELFCLASS ## B) { \
291 Elf ## B ## _Dyn *dyn; \
292 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
293 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
294 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
295 Elf ## B ## _Off offset; \
296 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
297 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
298 offset = EGET(phdr[i].p_offset); \
299 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
300 dyn = DYN ## B (elf->data + offset); \
301 while (EGET(dyn->d_tag) != DT_NULL) { \
302 if (EGET(dyn->d_tag) == DT_NEEDED) { \
303 offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \
304 if (offset >= elf->len) { \
305 ++dyn; \
306 continue; \
307 } \
308 needed = (char*)(elf->data + offset); \
309 if (*found_needed) xchrcat(ret, ',', ret_len); \
310 xstrcat(ret, needed, ret_len); \
311 *found_needed = 1; \
312 } \
313 ++dyn; \
314 } \
315 } }
316 SHOW_NEEDED(32)
317 SHOW_NEEDED(64)
318 }
319 }
320 static char *scanelf_file_interp(elfobj *elf, char *found_interp)
321 {
322 void *strtbl_void;
323
324 if (!show_interp) return NULL;
325
326 strtbl_void = elf_findsecbyname(elf, ".interp");
327
328 if (strtbl_void) {
329 #define SHOW_INTERP(B) \
330 if (elf->elf_class == ELFCLASS ## B) { \
331 Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \
332 *found_interp = 1; \
333 return elf->data + EGET(strtbl->sh_offset); \
334 }
335 SHOW_INTERP(32)
336 SHOW_INTERP(64)
337 }
338 return NULL;
339 }
340 static char *scanelf_file_bind(elfobj *elf, char *found_bind)
341 {
342 unsigned long i;
343 struct stat s;
344
345 if (!show_bind) return NULL;
346 if (!elf->phdr) return NULL;
347
348 #define SHOW_BIND(B) \
349 if (elf->elf_class == ELFCLASS ## B) { \
350 Elf ## B ## _Dyn *dyn; \
351 Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
352 Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
353 Elf ## B ## _Off offset; \
354 for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
355 if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \
356 offset = EGET(phdr[i].p_offset); \
357 if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \
358 dyn = DYN ## B (elf->data + offset); \
359 while (EGET(dyn->d_tag) != DT_NULL) { \
360 if (EGET(dyn->d_tag) == DT_BIND_NOW || \
361 (EGET(dyn->d_tag) == DT_FLAGS && EGET(dyn->d_un.d_val) & DF_BIND_NOW)) \
362 { \
363 if (be_quiet) return NULL; \
364 *found_bind = 1; \
365 return "NOW"; \
366 } \
367 ++dyn; \
368 } \
369 } \
370 }
371 SHOW_BIND(32)
372 SHOW_BIND(64)
373
374 if (be_quiet && !fstat(elf->fd, &s) && !(s.st_mode & S_ISUID || s.st_mode & S_ISGID)) {
375 return NULL;
376 } else {
377 *found_bind = 1;
378 return "LAZY";
379 }
380 }
381 static char *scanelf_file_sym(elfobj *elf, char *found_sym, const char *filename)
382 {
383 unsigned long i;
384 void *symtab_void, *strtab_void;
385
386 if (!find_sym) return NULL;
387
388 /* debug sections */
389 symtab_void = elf_findsecbyname(elf, ".symtab");
390 strtab_void = elf_findsecbyname(elf, ".strtab");
391 /* fall back to runtime sections */
392 if (!symtab_void || !strtab_void) {
393 symtab_void = elf_findsecbyname(elf, ".dynsym");
394 strtab_void = elf_findsecbyname(elf, ".dynstr");
395 }
396
397 if (symtab_void && strtab_void) {
398 char *base, *basemem;
399 basemem = xstrdup(filename);
400 base = basename(basemem);
401 #define FIND_SYM(B) \
402 if (elf->elf_class == ELFCLASS ## B) { \
403 Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
404 Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
405 Elf ## B ## _Sym *sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \
406 unsigned long cnt = EGET(symtab->sh_size) / EGET(symtab->sh_entsize); \
407 char *symname; \
408 for (i = 0; i < cnt; ++i) { \
409 if (sym->st_name) { \
410 symname = (char *)(elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name)); \
411 if (*find_sym == '*') { \
412 printf("%s(%s) %5lX %15s %s\n", \
413 ((*found_sym == 0) ? "\n\t" : "\t"), \
414 base, \
415 (long)sym->st_size, \
416 (char *)get_elfstttype(sym->st_info), \
417 symname); \
418 *found_sym = 1; \
419 } else if ((strcmp(find_sym, symname) == 0) || \
420 (strcmp(symname, versioned_symname) == 0)) \
421 (*found_sym)++; \
422 } \
423 ++sym; \
424 } }
425 FIND_SYM(32)
426 FIND_SYM(64)
427 free(basemem);
428 }
429 if (*find_sym != '*' && *found_sym)
430 return find_sym;
431 if (be_quiet)
432 return NULL;
433 else
434 return " - ";
435 }
436 /* scan an elf file and show all the fun stuff */
437 // #define prints(str) fputs(str, stdout)
438 #define prints(str) write(fileno(stdout), str, strlen(str))
439 static void scanelf_file(const char *filename)
440 {
441 unsigned long i;
442 char found_pax, found_stack, found_relro, found_textrel,
443 found_rpath, found_needed, found_interp, found_bind,
444 found_sym, found_file;
445 elfobj *elf;
446 struct stat st;
447 static char *out_buffer = NULL;
448 static size_t out_len;
449
450 /* make sure 'filename' exists */
451 if (lstat(filename, &st) == -1) {
452 if (be_verbose > 2) printf("%s: does not exist\n", filename);
453 return;
454 }
455 /* always handle regular files and handle symlinked files if no -y */
456 if (S_ISLNK(st.st_mode)) {
457 if (!scan_symlink) return;
458 stat(filename, &st);
459 }
460 if (!S_ISREG(st.st_mode)) {
461 if (be_verbose > 2) printf("%s: skipping non-file\n", filename);
462 return;
463 }
464
465 found_pax = found_stack = found_relro = found_textrel = \
466 found_rpath = found_needed = found_interp = found_bind = \
467 found_sym = found_file = 0;
468
469 /* verify this is real ELF */
470 if ((elf = readelf(filename)) == NULL) {
471 if (be_verbose > 2) printf("%s: not an ELF\n", filename);
472 return;
473 }
474
475 if (be_verbose > 1)
476 printf("%s: scanning file {%s,%s}\n", filename,
477 get_elfeitype(elf, EI_CLASS, elf->elf_class),
478 get_elfeitype(elf, EI_DATA, elf->data[EI_DATA]));
479 else if (be_verbose)
480 printf("%s: scanning file\n", filename);
481
482 /* init output buffer */
483 if (!out_buffer) {
484 out_len = sizeof(char) * 80;
485 out_buffer = (char*)xmalloc(out_len);
486 }
487 *out_buffer = '\0';
488
489 /* show the header */
490 if (!be_quiet && show_banner) {
491 for (i = 0; out_format[i]; ++i) {
492 if (out_format[i] != '%') continue;
493
494 switch (out_format[++i]) {
495 case '%': break;
496 case 'F':
497 case 'p':
498 case 'f': prints("FILE "); found_file = 1; break;
499 case 'o': prints(" TYPE "); break;
500 case 'x': prints(" PAX "); break;
501 case 'e': prints("STK/REL "); break;
502 case 't': prints("TEXTREL "); break;
503 case 'r': prints("RPATH "); break;
504 case 'n': prints("NEEDED "); break;
505 case 'i': prints("INTERP "); break;
506 case 'b': prints("BIND "); break;
507 case 's': prints("SYM "); break;
508 }
509 }
510 if (!found_file) prints("FILE ");
511 prints("\n");
512 found_file = 0;
513 show_banner = 0;
514 }
515
516 /* dump all the good stuff */
517 for (i = 0; out_format[i]; ++i) {
518 const char *out;
519 const char *tmp;
520
521 /* make sure we trim leading spaces in quiet mode */
522 if (be_quiet && *out_buffer == ' ' && !out_buffer[1])
523 *out_buffer = '\0';
524
525 if (out_format[i] != '%') {
526 xchrcat(&out_buffer, out_format[i], &out_len);
527 continue;
528 }
529
530 out = NULL;
531 switch (out_format[++i]) {
532 case '%': xchrcat(&out_buffer, '%', &out_len); break;
533 case 'F': found_file = 1; xstrcat(&out_buffer, filename, &out_len); break;
534 case 'p':
535 found_file = 1;
536 tmp = filename;
537 if (search_path) {
538 ssize_t len_search = strlen(search_path);
539 ssize_t len_file = strlen(filename);
540 if (!strncmp(filename, search_path, len_search) && \
541 len_file > len_search)
542 tmp += len_search;
543 if (*tmp == '/' && search_path[len_search-1] == '/') tmp++;
544 }
545 xstrcat(&out_buffer, tmp, &out_len);
546 break;
547 case 'f':
548 found_file = 1;
549 tmp = strrchr(filename, '/');
550 tmp = (tmp == NULL ? filename : tmp+1);
551 xstrcat(&out_buffer, tmp, &out_len);
552 break;
553 case 'o': out = get_elfetype(elf); break;
554 case 'x': out = scanelf_file_pax(elf, &found_pax); break;
555 case 'e': out = scanelf_file_stack(elf, &found_stack, &found_relro); break;
556 case 't': out = scanelf_file_textrel(elf, &found_textrel); break;
557 case 'r': scanelf_file_rpath(elf, &found_rpath, &out_buffer, &out_len); break;
558 case 'n': scanelf_file_needed(elf, &found_needed, &out_buffer, &out_len); break;
559 case 'i': out = scanelf_file_interp(elf, &found_interp); break;
560 case 'b': out = scanelf_file_bind(elf, &found_bind); break;
561 case 's': out = scanelf_file_sym(elf, &found_sym, filename); break;
562 }
563 if (out) xstrcat(&out_buffer, out, &out_len);
564 }
565
566 #define FOUND_SOMETHING() \
567 (found_pax || found_stack || found_textrel || found_rpath || \
568 found_needed || found_interp || found_bind || found_sym)
569
570 if (!found_file && (!be_quiet || (be_quiet && FOUND_SOMETHING()))) {
571 xchrcat(&out_buffer, ' ', &out_len);
572 xstrcat(&out_buffer, filename, &out_len);
573 }
574 if (!be_quiet || (be_quiet && FOUND_SOMETHING()))
575 puts(out_buffer);
576
577 unreadelf(elf);
578 }
579
580 /* scan a directory for ET_EXEC files and print when we find one */
581 static void scanelf_dir(const char *path)
582 {
583 register DIR *dir;
584 register struct dirent *dentry;
585 struct stat st_top, st;
586 char buf[_POSIX_PATH_MAX];
587 size_t pathlen = 0, len = 0;
588
589 /* make sure path exists */
590 if (lstat(path, &st_top) == -1) {
591 if (be_verbose > 2) printf("%s: does not exist\n", path);
592 return;
593 }
594
595 /* ok, if it isn't a directory, assume we can open it */
596 if (!S_ISDIR(st_top.st_mode)) {
597 scanelf_file(path);
598 return;
599 }
600
601 /* now scan the dir looking for fun stuff */
602 if ((dir = opendir(path)) == NULL) {
603 warnf("could not opendir %s: %s", path, strerror(errno));
604 return;
605 }
606 if (be_verbose) printf("%s: scanning dir\n", path);
607
608 pathlen = strlen(path);
609 while ((dentry = readdir(dir))) {
610 if (!strcmp(dentry->d_name, ".") || !strcmp(dentry->d_name, ".."))
611 continue;
612 len = (pathlen + 1 + strlen(dentry->d_name) + 1);
613 if (len >= sizeof(buf)) {
614 warnf("Skipping '%s': len > sizeof(buf); %d > %d\n", path, (int)len, (int)sizeof(buf));
615 continue;
616 }
617 sprintf(buf, "%s/%s", path, dentry->d_name);
618 if (lstat(buf, &st) != -1) {
619 if (S_ISREG(st.st_mode))
620 scanelf_file(buf);
621 else if (dir_recurse && S_ISDIR(st.st_mode)) {
622 if (dir_crossmount || (st_top.st_dev == st.st_dev))
623 scanelf_dir(buf);
624 }
625 }
626 }
627 closedir(dir);
628 }
629
630 static int scanelf_from_file(char *filename)
631 {
632 FILE *fp = NULL;
633 char *p;
634 char path[_POSIX_PATH_MAX];
635
636 if (((strcmp(filename, "-")) == 0) && (ttyname(0) == NULL))
637 fp = stdin;
638 else if ((fp = fopen(filename, "r")) == NULL)
639 return 1;
640
641 while ((fgets(path, _POSIX_PATH_MAX, fp)) != NULL) {
642 if ((p = strchr(path, '\n')) != NULL)
643 *p = 0;
644 search_path = path;
645 scanelf_dir(path);
646 }
647 if (fp != stdin)
648 fclose(fp);
649 return 0;
650 }
651
652 static void load_ld_so_conf()
653 {
654 FILE *fp = NULL;
655 char *p;
656 char path[_POSIX_PATH_MAX];
657 int i = 0;
658
659 if ((fp = fopen("/etc/ld.so.conf", "r")) == NULL)
660 return;
661
662 while ((fgets(path, _POSIX_PATH_MAX, fp)) != NULL) {
663 if (*path != '/')
664 continue;
665
666 if ((p = strrchr(path, '\r')) != NULL)
667 *p = 0;
668 if ((p = strchr(path, '\n')) != NULL)
669 *p = 0;
670
671 ldpaths[i++] = xstrdup(path);
672
673 if (i + 1 == sizeof(ldpaths) / sizeof(*ldpaths))
674 break;
675 }
676 ldpaths[i] = NULL;
677
678 fclose(fp);
679 }
680
681 /* scan /etc/ld.so.conf for paths */
682 static void scanelf_ldpath()
683 {
684 char scan_l, scan_ul, scan_ull;
685 int i = 0;
686
687 if (!ldpaths[0])
688 err("Unable to load any paths from ld.so.conf");
689
690 scan_l = scan_ul = scan_ull = 0;
691
692 while (ldpaths[i]) {
693 if (!scan_l && !strcmp(ldpaths[i], "/lib")) scan_l = 1;
694 if (!scan_ul && !strcmp(ldpaths[i], "/usr/lib")) scan_ul = 1;
695 if (!scan_ull && !strcmp(ldpaths[i], "/usr/local/lib")) scan_ull = 1;
696 scanelf_dir(ldpaths[i]);
697 ++i;
698 }
699
700 if (!scan_l) scanelf_dir("/lib");
701 if (!scan_ul) scanelf_dir("/usr/lib");
702 if (!scan_ull) scanelf_dir("/usr/local/lib");
703 }
704
705 /* scan env PATH for paths */
706 static void scanelf_envpath()
707 {
708 char *path, *p;
709
710 path = getenv("PATH");
711 if (!path)
712 err("PATH is not set in your env !");
713 path = xstrdup(path);
714
715 while ((p = strrchr(path, ':')) != NULL) {
716 scanelf_dir(p + 1);
717 *p = 0;
718 }
719
720 free(path);
721 }
722
723
724
725 /* usage / invocation handling functions */
726 #define PARSE_FLAGS "plRmyxetrnibs:aqvF:f:o:BhV"
727 #define a_argument required_argument
728 static struct option const long_opts[] = {
729 {"path", no_argument, NULL, 'p'},
730 {"ldpath", no_argument, NULL, 'l'},
731 {"recursive", no_argument, NULL, 'R'},
732 {"mount", no_argument, NULL, 'm'},
733 {"symlink", no_argument, NULL, 'y'},
734 {"pax", no_argument, NULL, 'x'},
735 {"header", no_argument, NULL, 'e'},
736 {"textrel", no_argument, NULL, 't'},
737 {"rpath", no_argument, NULL, 'r'},
738 {"needed", no_argument, NULL, 'n'},
739 {"interp", no_argument, NULL, 'i'},
740 {"bind", no_argument, NULL, 'b'},
741 {"symbol", a_argument, NULL, 's'},
742 {"all", no_argument, NULL, 'a'},
743 {"quiet", no_argument, NULL, 'q'},
744 {"verbose", no_argument, NULL, 'v'},
745 {"format", a_argument, NULL, 'F'},
746 {"from", a_argument, NULL, 'f'},
747 {"file", a_argument, NULL, 'o'},
748 {"nobanner", no_argument, NULL, 'B'},
749 {"help", no_argument, NULL, 'h'},
750 {"version", no_argument, NULL, 'V'},
751 {NULL, no_argument, NULL, 0x0}
752 };
753
754 static char *opts_help[] = {
755 "Scan all directories in PATH environment",
756 "Scan all directories in /etc/ld.so.conf",
757 "Scan directories recursively",
758 "Don't recursively cross mount points",
759 "Don't scan symlinks\n",
760 "Print PaX markings",
761 "Print GNU_STACK markings",
762 "Print TEXTREL information",
763 "Print RPATH information",
764 "Print NEEDED information",
765 "Print INTERP information",
766 "Print BIND information",
767 "Find a specified symbol",
768 "Print all scanned info (-x -e -t -r -n -i -b)\n",
769 "Only output 'bad' things",
770 "Be verbose (can be specified more than once)",
771 "Use specified format for output",
772 "Read input stream from a filename",
773 "Write output stream to a filename",
774 "Don't display the header",
775 "Print this help and exit",
776 "Print version and exit",
777 NULL
778 };
779
780 /* display usage and exit */
781 static void usage(int status)
782 {
783 unsigned long i;
784 printf("* Scan ELF binaries for stuff\n\n"
785 "Usage: %s [options] <dir1/file1> [dir2 dirN fileN ...]\n\n", argv0);
786 printf("Options: -[%s]\n", PARSE_FLAGS);
787 for (i = 0; long_opts[i].name; ++i)
788 if (long_opts[i].has_arg == no_argument)
789 printf(" -%c, --%-13s* %s\n", long_opts[i].val,
790 long_opts[i].name, opts_help[i]);
791 else
792 printf(" -%c, --%-6s <arg> * %s\n", long_opts[i].val,
793 long_opts[i].name, opts_help[i]);
794
795 if (status != EXIT_SUCCESS)
796 exit(status);
797
798 puts("\nThe format modifiers for the -F option are:");
799 puts(" %F Filename \t%x PaX Flags \t%e STACK/RELRO");
800 puts(" %t TEXTREL \t%r RPATH \t%n NEEDED");
801 puts(" %i INTERP \t%b BIND \t%s symbol");
802 puts(" %p filename (with search path removed)");
803 puts(" %f base filename");
804
805 exit(status);
806 }
807
808 /* parse command line arguments and preform needed actions */
809 static void parseargs(int argc, char *argv[])
810 {
811 int i;
812 char *from_file = NULL;
813
814 opterr = 0;
815 while ((i=getopt_long(argc, argv, PARSE_FLAGS, long_opts, NULL)) != -1) {
816 switch (i) {
817
818 case 'V':
819 printf("%s compiled %s\n%s\n"
820 "%s written for Gentoo Linux by <solar and vapier @ gentoo.org>\n",
821 __FILE__, __DATE__, rcsid, argv0);
822 exit(EXIT_SUCCESS);
823 break;
824 case 'h': usage(EXIT_SUCCESS); break;
825 case 'f':
826 if (from_file) err("Don't specify -f twice");
827 from_file = xstrdup(optarg);
828 break;
829 case 'o': {
830 FILE *fp = NULL;
831 if ((fp = freopen(optarg, "w", stdout)) == NULL)
832 err("Could not open output stream '%s': %s", optarg, strerror(errno));
833 SET_STDOUT(fp);
834 break;
835 }
836
837 case 's': {
838 size_t len;
839 if (find_sym) err("Don't specify -s twice");
840 find_sym = xstrdup(optarg);
841 len = strlen(find_sym) + 1;
842 versioned_symname = (char*)xmalloc(sizeof(char) * (len+1));
843 sprintf(versioned_symname, "%s@", find_sym);
844 break;
845 }
846
847 case 'F': {
848 if (out_format) err("Don't specify -F twice");
849 out_format = xstrdup(optarg);
850 break;
851 }
852
853 case 'y': scan_symlink = 0; break;
854 case 'B': show_banner = 0; break;
855 case 'l': scan_ldpath = 1; break;
856 case 'p': scan_envpath = 1; break;
857 case 'R': dir_recurse = 1; break;
858 case 'm': dir_crossmount = 0; break;
859 case 'x': show_pax = 1; break;
860 case 'e': show_stack = 1; break;
861 case 't': show_textrel = 1; break;
862 case 'r': show_rpath = 1; break;
863 case 'n': show_needed = 1; break;
864 case 'i': show_interp = 1; break;
865 case 'b': show_bind = 1; break;
866 case 'q': be_quiet = 1; break;
867 case 'v': be_verbose = (be_verbose % 20) + 1; break;
868 case 'a': show_pax = show_stack = show_textrel = show_rpath = \
869 show_needed = show_interp = show_bind = 1; break;
870
871 case ':':
872 err("Option missing parameter\n");
873 case '?':
874 err("Unknown option\n");
875 default:
876 err("Unhandled option '%c'", i);
877 }
878 }
879
880 /* let the format option override all other options */
881 if (out_format) {
882 show_pax = show_stack = show_textrel = show_rpath = \
883 show_needed = show_interp = show_bind = 0;
884 for (i = 0; out_format[i]; ++i) {
885 if (out_format[i] != '%') continue;
886
887 switch (out_format[++i]) {
888 case '%': break;
889 case 'F': break;
890 case 'p': break;
891 case 'f': break;
892 case 's': break;
893 case 'o': break;
894 case 'x': show_pax = 1; break;
895 case 'e': show_stack = 1; break;
896 case 't': show_textrel = 1; break;
897 case 'r': show_rpath = 1; break;
898 case 'n': show_needed = 1; break;
899 case 'i': show_interp = 1; break;
900 case 'b': show_bind = 1; break;
901 default:
902 err("Invalid format specifier '%c' (byte %i)",
903 out_format[i], i+1);
904 }
905 }
906
907 /* construct our default format */
908 } else {
909 size_t fmt_len = 30;
910 out_format = (char*)xmalloc(sizeof(char) * fmt_len);
911 if (!be_quiet) xstrcat(&out_format, "%o ", &fmt_len);
912 if (show_pax) xstrcat(&out_format, "%x ", &fmt_len);
913 if (show_stack) xstrcat(&out_format, "%e ", &fmt_len);
914 if (show_textrel) xstrcat(&out_format, "%t ", &fmt_len);
915 if (show_rpath) xstrcat(&out_format, "%r ", &fmt_len);
916 if (show_needed) xstrcat(&out_format, "%n ", &fmt_len);
917 if (show_interp) xstrcat(&out_format, "%i ", &fmt_len);
918 if (show_bind) xstrcat(&out_format, "%b ", &fmt_len);
919 if (find_sym) xstrcat(&out_format, "%s ", &fmt_len);
920 if (!be_quiet) xstrcat(&out_format, "%F ", &fmt_len);
921 }
922 if (be_verbose > 2) printf("Format: %s\n", out_format);
923
924 /* now lets actually do the scanning */
925 if (scan_ldpath || (show_rpath && be_quiet))
926 load_ld_so_conf();
927 if (scan_ldpath) scanelf_ldpath();
928 if (scan_envpath) scanelf_envpath();
929 if (from_file) {
930 scanelf_from_file(from_file);
931 free(from_file);
932 from_file = *argv;
933 }
934 if (optind == argc && !scan_ldpath && !scan_envpath && !from_file)
935 err("Nothing to scan !?");
936 while (optind < argc) {
937 search_path = argv[optind++];
938 scanelf_dir(search_path);
939 }
940
941 /* clean up */
942 if (find_sym) {
943 free(find_sym);
944 free(versioned_symname);
945 }
946 if (out_format) free(out_format);
947 for (i = 0; ldpaths[i]; ++i)
948 free(ldpaths[i]);
949 }
950
951
952
953 /* utility funcs */
954 static char *xstrdup(const char *s)
955 {
956 char *ret = strdup(s);
957 if (!ret) err("Could not strdup(): %s", strerror(errno));
958 return ret;
959 }
960
961 static void *xmalloc(size_t size)
962 {
963 void *ret = malloc(size);
964 if (!ret) err("Could not malloc() %li bytes", (unsigned long)size);
965 return ret;
966 }
967
968 static void xstrcat(char **dst, const char *src, size_t *curr_len)
969 {
970 long new_len;
971
972 new_len = strlen(*dst) + strlen(src);
973 if (*curr_len <= new_len) {
974 *curr_len = new_len + (*curr_len / 2);
975 *dst = realloc(*dst, *curr_len);
976 if (!*dst)
977 err("could not realloc %li bytes", (unsigned long)*curr_len);
978 }
979
980 strcat(*dst, src);
981 }
982
983 static inline void xchrcat(char **dst, const char append, size_t *curr_len)
984 {
985 static char my_app[2];
986 my_app[0] = append;
987 my_app[1] = '\0';
988 xstrcat(dst, my_app, curr_len);
989 }
990
991
992 int main(int argc, char *argv[])
993 {
994 if (argc < 2)
995 usage(EXIT_FAILURE);
996 parseargs(argc, argv);
997 fclose(stdout);
998 #ifdef __BOUNDS_CHECKING_ON
999 warn("The calls to add/delete heap should be off by 1 due to the out_buffer not being freed in scanelf_file()");
1000 #endif
1001 return EXIT_SUCCESS;
1002 }

  ViewVC Help
Powered by ViewVC 1.1.20