Line data Source code
1 : /* Print the strings of printable characters in files.
2 : Copyright (C) 2005-2010, 2012, 2014 Red Hat, Inc.
3 : This file is part of elfutils.
4 : Written by Ulrich Drepper <drepper@redhat.com>, 2005.
5 :
6 : This file is free software; you can redistribute it and/or modify
7 : it under the terms of the GNU General Public License as published by
8 : the Free Software Foundation; either version 3 of the License, or
9 : (at your option) any later version.
10 :
11 : elfutils is distributed in the hope that it will be useful, but
12 : WITHOUT ANY WARRANTY; without even the implied warranty of
13 : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 : GNU General Public License for more details.
15 :
16 : You should have received a copy of the GNU General Public License
17 : along with this program. If not, see <http://www.gnu.org/licenses/>. */
18 :
19 : #ifdef HAVE_CONFIG_H
20 : # include <config.h>
21 : #endif
22 :
23 : #include <argp.h>
24 : #include <assert.h>
25 : #include <ctype.h>
26 : #include <endian.h>
27 : #include <errno.h>
28 : #include <fcntl.h>
29 : #include <gelf.h>
30 : #include <inttypes.h>
31 : #include <libintl.h>
32 : #include <locale.h>
33 : #include <stdbool.h>
34 : #include <stdio.h>
35 : #include <stdio_ext.h>
36 : #include <stdlib.h>
37 : #include <string.h>
38 : #include <unistd.h>
39 : #include <sys/mman.h>
40 : #include <sys/stat.h>
41 :
42 : #include <libeu.h>
43 : #include <system.h>
44 : #include <printversion.h>
45 :
46 : #ifndef MAP_POPULATE
47 : # define MAP_POPULATE 0
48 : #endif
49 :
50 :
51 : /* Prototypes of local functions. */
52 : static int read_fd (int fd, const char *fname, off_t fdlen);
53 : static int read_elf (Elf *elf, int fd, const char *fname, off_t fdlen);
54 :
55 :
56 : /* Name and version of program. */
57 : ARGP_PROGRAM_VERSION_HOOK_DEF = print_version;
58 :
59 : /* Bug report address. */
60 : ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT;
61 :
62 : /* Definitions of arguments for argp functions. */
63 : static const struct argp_option options[] =
64 : {
65 : { NULL, 0, NULL, 0, N_("Output Selection:"), 0 },
66 : { "all", 'a', NULL, 0, N_("Scan entire file, not only loaded sections"), 0 },
67 : { "bytes", 'n', "MIN-LEN", 0,
68 : N_("Only NUL-terminated sequences of MIN-LEN characters or more are printed"), 0 },
69 : { "encoding", 'e', "SELECTOR", 0, N_("\
70 : Select character size and endianess: s = 7-bit, S = 8-bit, {b,l} = 16-bit, {B,L} = 32-bit"),
71 : 0},
72 : { "print-file-name", 'f', NULL, 0,
73 : N_("Print name of the file before each string."), 0 },
74 : { "radix", 't', "{o,d,x}", 0,
75 : N_("Print location of the string in base 8, 10, or 16 respectively."), 0 },
76 : { NULL, 'o', NULL, 0, N_("Alias for --radix=o"), 0 },
77 :
78 : { NULL, 0, NULL, 0, N_("Miscellaneous:"), 0 },
79 : { NULL, 0, NULL, 0, NULL, 0 }
80 : };
81 :
82 : /* Short description of program. */
83 : static const char doc[] = N_("\
84 : Print the strings of printable characters in files.");
85 :
86 : /* Strings for arguments in help texts. */
87 : static const char args_doc[] = N_("[FILE...]");
88 :
89 : /* Prototype for option handler. */
90 : static error_t parse_opt (int key, char *arg, struct argp_state *state);
91 :
92 : /* Data structure to communicate with argp functions. */
93 : static struct argp argp =
94 : {
95 : options, parse_opt, args_doc, doc, NULL, NULL, NULL
96 : };
97 :
98 :
99 : /* Global variables. */
100 :
101 : /* True if whole file and not only loaded sections are looked at. */
102 : static bool entire_file;
103 :
104 : /* Minimum length of any sequence reported. */
105 : static size_t min_len = 4;
106 :
107 : /* Number of bytes per character. */
108 : static size_t bytes_per_char = 1;
109 :
110 : /* Minimum length of any sequence reported in bytes. */
111 : static size_t min_len_bytes;
112 :
113 : /* True if multibyte characters are in big-endian order. */
114 : static bool big_endian;
115 :
116 : /* True unless 7-bit ASCII are expected. */
117 : static bool char_7bit;
118 :
119 : /* True if file names should be printed before strings. */
120 : static bool print_file_name;
121 :
122 : /* Radix for printed numbers. */
123 : static enum
124 : {
125 : radix_none = 0,
126 : radix_decimal,
127 : radix_hex,
128 : radix_octal
129 : } radix = radix_none;
130 :
131 :
132 : /* Page size in use. */
133 : static size_t ps;
134 :
135 :
136 : /* Mapped parts of the ELF file. */
137 : static unsigned char *elfmap;
138 : static unsigned char *elfmap_base;
139 : static size_t elfmap_size;
140 : static off_t elfmap_off;
141 :
142 :
143 : int
144 1 : main (int argc, char *argv[])
145 : {
146 : /* We use no threads. */
147 1 : __fsetlocking (stdin, FSETLOCKING_BYCALLER);
148 1 : __fsetlocking (stdout, FSETLOCKING_BYCALLER);
149 :
150 : /* Set locale. */
151 1 : (void) setlocale (LC_ALL, "");
152 :
153 : /* Make sure the message catalog can be found. */
154 1 : (void) bindtextdomain (PACKAGE_TARNAME, LOCALEDIR);
155 :
156 : /* Initialize the message catalog. */
157 1 : (void) textdomain (PACKAGE_TARNAME);
158 :
159 : /* Parse and process arguments. */
160 : int remaining;
161 1 : (void) argp_parse (&argp, argc, argv, 0, &remaining, NULL);
162 :
163 : /* Tell the library which version we are expecting. */
164 1 : elf_version (EV_CURRENT);
165 :
166 : /* Determine the page size. We will likely need it a couple of times. */
167 1 : ps = sysconf (_SC_PAGESIZE);
168 :
169 : struct stat st;
170 1 : int result = 0;
171 1 : if (remaining == argc)
172 : /* We read from standard input. This we cannot do for a
173 : structured file. */
174 0 : result = read_fd (STDIN_FILENO,
175 0 : print_file_name ? "{standard input}" : NULL,
176 0 : (fstat (STDIN_FILENO, &st) == 0 && S_ISREG (st.st_mode))
177 : ? st.st_size : INT64_C (0x7fffffffffffffff));
178 : else
179 : do
180 : {
181 18 : int fd = (strcmp (argv[remaining], "-") == 0
182 18 : ? STDIN_FILENO : open (argv[remaining], O_RDONLY));
183 9 : if (unlikely (fd == -1))
184 : {
185 0 : error (0, errno, gettext ("cannot open '%s'"), argv[remaining]);
186 0 : result = 1;
187 : }
188 : else
189 : {
190 9 : const char *fname = print_file_name ? argv[remaining] : NULL;
191 9 : int fstat_fail = fstat (fd, &st);
192 9 : off_t fdlen = (fstat_fail
193 9 : ? INT64_C (0x7fffffffffffffff) : st.st_size);
194 9 : if (fdlen > (off_t) min_len_bytes)
195 : {
196 9 : Elf *elf = NULL;
197 9 : if (entire_file
198 9 : || fstat_fail
199 9 : || !S_ISREG (st.st_mode)
200 9 : || (elf = elf_begin (fd, ELF_C_READ, NULL)) == NULL
201 9 : || elf_kind (elf) != ELF_K_ELF)
202 0 : result |= read_fd (fd, fname, fdlen);
203 : else
204 9 : result |= read_elf (elf, fd, fname, fdlen);
205 :
206 : /* This call will succeed even if ELF is NULL. */
207 9 : elf_end (elf);
208 : }
209 :
210 9 : if (strcmp (argv[remaining], "-") != 0)
211 9 : close (fd);
212 : }
213 :
214 9 : if (elfmap != NULL && elfmap != MAP_FAILED)
215 0 : munmap (elfmap, elfmap_size);
216 9 : elfmap = NULL;
217 : }
218 9 : while (++remaining < argc);
219 :
220 : return result;
221 : }
222 :
223 :
224 : /* Handle program arguments. */
225 : static error_t
226 7 : parse_opt (int key, char *arg,
227 : struct argp_state *state __attribute__ ((unused)))
228 : {
229 7 : switch (key)
230 : {
231 0 : case 'a':
232 0 : entire_file = true;
233 0 : break;
234 :
235 0 : case 'e':
236 : /* We expect a string of one character. */
237 0 : switch (arg[1] != '\0' ? '\0' : arg[0])
238 : {
239 0 : case 's':
240 : case 'S':
241 0 : char_7bit = arg[0] == 's';
242 0 : bytes_per_char = 1;
243 0 : break;
244 :
245 0 : case 'b':
246 : case 'B':
247 0 : big_endian = true;
248 : FALLTHROUGH;
249 :
250 0 : case 'l':
251 : case 'L':
252 0 : bytes_per_char = isupper (arg[0]) ? 4 : 2;
253 0 : break;
254 :
255 0 : default:
256 0 : error (0, 0, gettext ("invalid value '%s' for %s parameter"),
257 : arg, "-e");
258 0 : argp_help (&argp, stderr, ARGP_HELP_SEE, "strings");
259 0 : return ARGP_ERR_UNKNOWN;
260 : }
261 : break;
262 :
263 1 : case 'f':
264 1 : print_file_name = true;
265 1 : break;
266 :
267 0 : case 'n':
268 0 : min_len = atoi (arg);
269 0 : break;
270 :
271 : case 'o':
272 : goto octfmt;
273 :
274 1 : case 't':
275 1 : switch (arg[0])
276 : {
277 0 : case 'd':
278 0 : radix = radix_decimal;
279 0 : break;
280 :
281 : case 'o':
282 0 : octfmt:
283 0 : radix = radix_octal;
284 0 : break;
285 :
286 1 : case 'x':
287 1 : radix = radix_hex;
288 1 : break;
289 :
290 0 : default:
291 0 : error (0, 0, gettext ("invalid value '%s' for %s parameter"),
292 : arg, "-t");
293 0 : argp_help (&argp, stderr, ARGP_HELP_SEE, "strings");
294 0 : return ARGP_ERR_UNKNOWN;
295 : }
296 : break;
297 :
298 1 : case ARGP_KEY_FINI:
299 : /* Compute the length in bytes of any match. */
300 1 : if (min_len <= 0 || min_len > INT_MAX / bytes_per_char)
301 : error (EXIT_FAILURE, 0,
302 0 : gettext ("invalid minimum length of matched string size"));
303 1 : min_len_bytes = min_len * bytes_per_char;
304 1 : break;
305 :
306 : default:
307 : return ARGP_ERR_UNKNOWN;
308 : }
309 : return 0;
310 : }
311 :
312 :
313 : static void
314 0 : process_chunk_mb (const char *fname, const unsigned char *buf, off_t to,
315 : size_t len, char **unprinted)
316 : {
317 0 : size_t curlen = *unprinted == NULL ? 0 : strlen (*unprinted);
318 : const unsigned char *start = buf;
319 0 : while (len >= bytes_per_char)
320 : {
321 : uint32_t ch;
322 :
323 0 : if (bytes_per_char == 2)
324 : {
325 0 : if (big_endian)
326 0 : ch = buf[0] << 8 | buf[1];
327 : else
328 0 : ch = buf[1] << 8 | buf[0];
329 : }
330 : else
331 : {
332 0 : if (big_endian)
333 0 : ch = buf[0] << 24 | buf[1] << 16 | buf[2] << 8 | buf[3];
334 : else
335 0 : ch = buf[3] << 24 | buf[2] << 16 | buf[1] << 8 | buf[0];
336 : }
337 :
338 0 : if (ch <= 255 && (isprint (ch) || ch == '\t'))
339 : {
340 0 : ++buf;
341 0 : ++curlen;
342 : }
343 : else
344 : {
345 0 : if (curlen >= min_len)
346 : {
347 : /* We found a match. */
348 0 : if (unlikely (fname != NULL))
349 : {
350 0 : fputs_unlocked (fname, stdout);
351 0 : fputs_unlocked (": ", stdout);
352 : }
353 :
354 0 : if (unlikely (radix != radix_none))
355 0 : printf ((radix == radix_octal ? "%7" PRIo64 " "
356 : : (radix == radix_decimal ? "%7" PRId64 " "
357 : : "%7" PRIx64 " ")),
358 0 : (int64_t) to - len - (buf - start));
359 :
360 0 : if (unlikely (*unprinted != NULL))
361 : {
362 0 : fputs_unlocked (*unprinted, stdout);
363 0 : free (*unprinted);
364 0 : *unprinted = NULL;
365 : }
366 :
367 : /* There is no sane way of printing the string. If we
368 : assume the file data is encoded in UCS-2/UTF-16 or
369 : UCS-4/UTF-32 respectively we could covert the string.
370 : But there is no such guarantee. */
371 0 : fwrite_unlocked (start, 1, buf - start, stdout);
372 0 : putc_unlocked ('\n', stdout);
373 : }
374 :
375 0 : start = ++buf;
376 0 : curlen = 0;
377 :
378 0 : if (len <= min_len)
379 : break;
380 : }
381 :
382 0 : --len;
383 : }
384 :
385 0 : if (curlen != 0)
386 0 : *unprinted = xstrndup ((const char *) start, curlen);
387 0 : }
388 :
389 :
390 : static void
391 158 : process_chunk (const char *fname, const unsigned char *buf, off_t to,
392 : size_t len, char **unprinted)
393 : {
394 : /* We are not going to slow the check down for the 2- and 4-byte
395 : encodings. Handle them special. */
396 158 : if (unlikely (bytes_per_char != 1))
397 : {
398 0 : process_chunk_mb (fname, buf, to, len, unprinted);
399 0 : return;
400 : }
401 :
402 158 : size_t curlen = *unprinted == NULL ? 0 : strlen (*unprinted);
403 : const unsigned char *start = buf;
404 68044 : while (len > 0)
405 : {
406 68042 : if ((isprint (*buf) || *buf == '\t') && (! char_7bit || *buf <= 127))
407 : {
408 18503 : ++buf;
409 18503 : ++curlen;
410 : }
411 : else
412 : {
413 49539 : if (curlen >= min_len)
414 : {
415 : /* We found a match. */
416 443 : if (likely (fname != NULL))
417 : {
418 443 : fputs_unlocked (fname, stdout);
419 443 : fputs_unlocked (": ", stdout);
420 : }
421 :
422 443 : if (likely (radix != radix_none))
423 443 : printf ((radix == radix_octal ? "%7" PRIo64 " "
424 : : (radix == radix_decimal ? "%7" PRId64 " "
425 : : "%7" PRIx64 " ")),
426 443 : (int64_t) to - len - (buf - start));
427 :
428 443 : if (unlikely (*unprinted != NULL))
429 : {
430 0 : fputs_unlocked (*unprinted, stdout);
431 0 : free (*unprinted);
432 0 : *unprinted = NULL;
433 : }
434 443 : fwrite_unlocked (start, 1, buf - start, stdout);
435 443 : putc_unlocked ('\n', stdout);
436 : }
437 :
438 49539 : start = ++buf;
439 49539 : curlen = 0;
440 :
441 49539 : if (len <= min_len)
442 : break;
443 : }
444 :
445 67886 : --len;
446 : }
447 :
448 158 : if (curlen != 0)
449 0 : *unprinted = xstrndup ((const char *) start, curlen);
450 : }
451 :
452 :
453 : /* Map a file in as large chunks as possible. */
454 : static void *
455 9 : map_file (int fd, off_t start_off, off_t fdlen, size_t *map_sizep)
456 : {
457 : /* Maximum size we mmap. We use an #ifdef to avoid overflows on
458 : 32-bit machines. 64-bit machines these days do not have usable
459 : address spaces larger than about 43 bits. Not that any file
460 : should be that large. */
461 : # if SIZE_MAX > 0xffffffff
462 9 : const size_t mmap_max = 0x4000000000lu;
463 : # else
464 : const size_t mmap_max = 0x40000000lu;
465 : # endif
466 :
467 : /* Try to mmap the file. */
468 9 : size_t map_size = MIN ((off_t) mmap_max, fdlen);
469 9 : const size_t map_size_min = MAX (MAX (SIZE_MAX / 16, 2 * ps),
470 : roundup (2 * min_len_bytes + 1, ps));
471 : void *mem;
472 : while (1)
473 : {
474 : /* We map the memory for reading only here. Since we will
475 : always look at every byte of the file it makes sense to
476 : use MAP_POPULATE. */
477 9 : mem = mmap (NULL, map_size, PROT_READ, MAP_PRIVATE | MAP_POPULATE,
478 : fd, start_off);
479 9 : if (mem != MAP_FAILED)
480 : {
481 : /* We will go through the mapping sequentially. */
482 9 : (void) posix_madvise (mem, map_size, POSIX_MADV_SEQUENTIAL);
483 9 : break;
484 : }
485 0 : if (errno != EINVAL && errno != ENOMEM)
486 : /* This is an error other than the lack of address space. */
487 : break;
488 :
489 : /* Maybe the size of the mapping is too big. Try again. */
490 0 : map_size /= 2;
491 0 : if (map_size < map_size_min)
492 : /* That size should have fit. */
493 : break;
494 : }
495 :
496 9 : *map_sizep = map_size;
497 9 : return mem;
498 : }
499 :
500 :
501 : /* Read the file without mapping. */
502 : static int
503 0 : read_block_no_mmap (int fd, const char *fname, off_t from, off_t fdlen)
504 : {
505 0 : char *unprinted = NULL;
506 : #define CHUNKSIZE 65536
507 0 : unsigned char *buf = xmalloc (CHUNKSIZE + min_len_bytes
508 0 : + bytes_per_char - 1);
509 0 : size_t ntrailer = 0;
510 0 : int result = 0;
511 0 : while (fdlen > 0)
512 : {
513 0 : ssize_t n = TEMP_FAILURE_RETRY (read (fd, buf + ntrailer,
514 : MIN (fdlen, CHUNKSIZE)));
515 0 : if (n == 0)
516 : {
517 : /* There are less than MIN_LEN+1 bytes left so there cannot be
518 : another match. */
519 0 : assert (unprinted == NULL || ntrailer == 0);
520 : break;
521 : }
522 0 : if (unlikely (n < 0))
523 : {
524 : /* Something went wrong. */
525 : result = 1;
526 : break;
527 : }
528 :
529 : /* Account for the number of bytes read in this round. */
530 0 : fdlen -= n;
531 :
532 : /* Do not use the signed N value. Note that the addition cannot
533 : overflow. */
534 0 : size_t nb = (size_t) n + ntrailer;
535 0 : if (nb >= min_len_bytes)
536 : {
537 : /* We only use complete characters. */
538 0 : nb &= ~(bytes_per_char - 1);
539 :
540 0 : process_chunk (fname, buf, from + nb, nb, &unprinted);
541 :
542 : /* If the last bytes of the buffer (modulo the character
543 : size) have been printed we are not copying them. */
544 0 : size_t to_keep = unprinted != NULL ? 0 : min_len_bytes;
545 :
546 0 : memmove (buf, buf + nb - to_keep, to_keep);
547 0 : ntrailer = to_keep;
548 0 : from += nb;
549 : }
550 : else
551 : ntrailer = nb;
552 : }
553 :
554 0 : free (buf);
555 :
556 : /* Don't print anything we collected so far. There is no
557 : terminating NUL byte. */
558 0 : free (unprinted);
559 :
560 0 : return result;
561 : }
562 :
563 :
564 : static int
565 158 : read_block (int fd, const char *fname, off_t fdlen, off_t from, off_t to)
566 : {
567 158 : if (elfmap == NULL)
568 : {
569 : /* We need a completely new mapping. */
570 9 : elfmap_off = from & ~(ps - 1);
571 9 : elfmap_base = elfmap = map_file (fd, elfmap_off, fdlen, &elfmap_size);
572 :
573 9 : if (unlikely (elfmap == MAP_FAILED))
574 : /* Let the kernel know we are going to read everything in sequence. */
575 0 : (void) posix_fadvise (fd, 0, 0, POSIX_FADV_SEQUENTIAL);
576 : }
577 :
578 158 : if (unlikely (elfmap == MAP_FAILED))
579 : {
580 : /* Read from the file descriptor. For this we must position the
581 : read pointer. */
582 : // XXX Eventually add flag which avoids this if the position
583 : // XXX is known to match.
584 0 : if (from != 0 && lseek (fd, from, SEEK_SET) != from)
585 0 : error (EXIT_FAILURE, errno, gettext ("lseek failed"));
586 :
587 0 : return read_block_no_mmap (fd, fname, from, to - from);
588 : }
589 :
590 158 : assert ((off_t) min_len_bytes < fdlen);
591 :
592 158 : if (to < (off_t) elfmap_off || from > (off_t) (elfmap_off + elfmap_size))
593 : {
594 : /* The existing mapping cannot fit at all. Map the new area.
595 : We always map the full range of ELFMAP_SIZE bytes even if
596 : this extend beyond the end of the file. The Linux kernel
597 : handles this OK if the access pages are not touched. */
598 0 : elfmap_off = from & ~(ps - 1);
599 0 : if (mmap (elfmap, elfmap_size, PROT_READ,
600 : MAP_PRIVATE | MAP_POPULATE | MAP_FIXED, fd, from)
601 : == MAP_FAILED)
602 0 : error (EXIT_FAILURE, errno, gettext ("re-mmap failed"));
603 0 : elfmap_base = elfmap;
604 : }
605 :
606 158 : char *unprinted = NULL;
607 :
608 : /* Use the existing mapping as much as possible. If necessary, map
609 : new pages. */
610 158 : if (from >= (off_t) elfmap_off
611 158 : && from < (off_t) (elfmap_off + elfmap_size))
612 : /* There are at least a few bytes in this mapping which we can
613 : use. */
614 158 : process_chunk (fname, elfmap_base + (from - elfmap_off),
615 : MIN (to, (off_t) (elfmap_off + elfmap_size)),
616 158 : MIN (to, (off_t) (elfmap_off + elfmap_size)) - from,
617 : &unprinted);
618 :
619 158 : if (to > (off_t) (elfmap_off + elfmap_size))
620 : {
621 0 : unsigned char *remap_base = elfmap_base;
622 0 : size_t read_now = elfmap_size - (elfmap_base - elfmap);
623 :
624 0 : assert (from >= (off_t) elfmap_off
625 : && from < (off_t) (elfmap_off + elfmap_size));
626 0 : off_t handled_to = elfmap_off + elfmap_size;
627 0 : assert (elfmap == elfmap_base
628 : || (elfmap_base - elfmap
629 : == (ptrdiff_t) ((min_len_bytes + ps - 1) & ~(ps - 1))));
630 0 : if (elfmap == elfmap_base)
631 : {
632 0 : size_t keep_area = (min_len_bytes + ps - 1) & ~(ps - 1);
633 0 : assert (elfmap_size >= keep_area + ps);
634 : /* The keep area is used for the content of the previous
635 : buffer we have to keep. This means copying those bytes
636 : and for this we have to make the data writable. */
637 0 : if (unlikely (mprotect (elfmap, keep_area, PROT_READ | PROT_WRITE)
638 : != 0))
639 0 : error (EXIT_FAILURE, errno, gettext ("mprotect failed"));
640 :
641 0 : elfmap_base = elfmap + keep_area;
642 : }
643 :
644 : while (1)
645 : {
646 : /* Map the rest of the file, eventually again in pieces.
647 : We speed things up with a nice Linux feature. Note
648 : that we have at least two pages mapped. */
649 0 : size_t to_keep = unprinted != NULL ? 0 : min_len_bytes;
650 :
651 0 : assert (read_now >= to_keep);
652 0 : memmove (elfmap_base - to_keep,
653 0 : remap_base + read_now - to_keep, to_keep);
654 0 : remap_base = elfmap_base;
655 :
656 0 : assert ((elfmap_size - (elfmap_base - elfmap)) % bytes_per_char
657 : == 0);
658 0 : read_now = MIN (to - handled_to,
659 : (ptrdiff_t) elfmap_size - (elfmap_base - elfmap));
660 :
661 0 : assert (handled_to % ps == 0);
662 0 : assert (handled_to % bytes_per_char == 0);
663 0 : if (mmap (remap_base, read_now, PROT_READ,
664 : MAP_PRIVATE | MAP_POPULATE | MAP_FIXED, fd, handled_to)
665 : == MAP_FAILED)
666 0 : error (EXIT_FAILURE, errno, gettext ("re-mmap failed"));
667 0 : elfmap_off = handled_to;
668 :
669 0 : process_chunk (fname, remap_base - to_keep,
670 0 : elfmap_off + (read_now & ~(bytes_per_char - 1)),
671 0 : to_keep + (read_now & ~(bytes_per_char - 1)),
672 : &unprinted);
673 0 : handled_to += read_now;
674 0 : if (handled_to >= to)
675 : break;
676 : }
677 : }
678 :
679 : /* Don't print anything we collected so far. There is no
680 : terminating NUL byte. */
681 158 : free (unprinted);
682 :
683 158 : return 0;
684 : }
685 :
686 :
687 : static int
688 : read_fd (int fd, const char *fname, off_t fdlen)
689 : {
690 0 : return read_block (fd, fname, fdlen, 0, fdlen);
691 : }
692 :
693 :
694 : static int
695 9 : read_elf (Elf *elf, int fd, const char *fname, off_t fdlen)
696 : {
697 9 : assert (fdlen >= 0);
698 :
699 : /* We will look at each section separately. The ELF file is not
700 : mmapped. The libelf implementation will load the needed parts on
701 : demand. Since we only interate over the section header table the
702 : memory consumption at this stage is kept minimal. */
703 9 : Elf_Scn *scn = elf_nextscn (elf, NULL);
704 9 : if (scn == NULL)
705 0 : return read_fd (fd, fname, fdlen);
706 :
707 : int result = 0;
708 : do
709 : {
710 : GElf_Shdr shdr_mem;
711 276 : GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
712 :
713 : /* Only look in sections which are loaded at runtime and
714 : actually have content. */
715 276 : if (shdr != NULL && shdr->sh_type != SHT_NOBITS
716 265 : && (shdr->sh_flags & SHF_ALLOC) != 0)
717 : {
718 158 : if (shdr->sh_offset > (Elf64_Off) fdlen
719 158 : || fdlen - shdr->sh_offset < shdr->sh_size)
720 0 : {
721 0 : size_t strndx = 0;
722 : const char *sname;
723 0 : if (unlikely (elf_getshdrstrndx (elf, &strndx) < 0))
724 : sname = "<unknown>";
725 : else
726 0 : sname = elf_strptr (elf, strndx, shdr->sh_name) ?: "<unknown>";
727 0 : error (0, 0,
728 0 : gettext ("Skipping section %zd '%s' data outside file"),
729 : elf_ndxscn (scn), sname);
730 0 : result = 1;
731 : }
732 : else
733 158 : result |= read_block (fd, fname, fdlen, shdr->sh_offset,
734 158 : shdr->sh_offset + shdr->sh_size);
735 : }
736 : }
737 276 : while ((scn = elf_nextscn (elf, scn)) != NULL);
738 :
739 9 : if (elfmap != NULL && elfmap != MAP_FAILED)
740 9 : munmap (elfmap, elfmap_size);
741 9 : elfmap = NULL;
742 :
743 9 : return result;
744 : }
745 :
746 :
747 : #include "debugpred.h"
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