2 * Copyright (c) 2007-2011,2014 Kai Wang
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/param.h>
37 ELFTC_VCSID("$Id: sections.c 3443 2016-04-15 18:57:54Z kaiwang27 $");
39 static void add_gnu_debuglink(struct elfcopy *ecp);
40 static uint32_t calc_crc32(const char *p, size_t len, uint32_t crc);
41 static void check_section_rename(struct elfcopy *ecp, struct section *s);
42 static void filter_reloc(struct elfcopy *ecp, struct section *s);
43 static int get_section_flags(struct elfcopy *ecp, const char *name);
44 static void insert_sections(struct elfcopy *ecp);
45 static void insert_to_strtab(struct section *t, const char *s);
46 static int is_append_section(struct elfcopy *ecp, const char *name);
47 static int is_compress_section(struct elfcopy *ecp, const char *name);
48 static int is_debug_section(const char *name);
49 static int is_dwo_section(const char *name);
50 static int is_modify_section(struct elfcopy *ecp, const char *name);
51 static int is_print_section(struct elfcopy *ecp, const char *name);
52 static int lookup_string(struct section *t, const char *s);
53 static void modify_section(struct elfcopy *ecp, struct section *s);
54 static void pad_section(struct elfcopy *ecp, struct section *s);
55 static void print_data(const char *d, size_t sz);
56 static void print_section(struct section *s);
57 static void *read_section(struct section *s, size_t *size);
58 static void update_reloc(struct elfcopy *ecp, struct section *s);
59 static void update_section_group(struct elfcopy *ecp, struct section *s);
62 is_remove_section(struct elfcopy *ecp, const char *name)
65 /* Always keep section name table */
66 if (strcmp(name, ".shstrtab") == 0)
68 if (strcmp(name, ".symtab") == 0 ||
69 strcmp(name, ".strtab") == 0) {
70 if (ecp->strip == STRIP_ALL && lookup_symop_list(
71 ecp, NULL, SYMOP_KEEP) == NULL)
77 if (ecp->strip == STRIP_DWO && is_dwo_section(name))
79 if (ecp->strip == STRIP_NONDWO && !is_dwo_section(name))
82 if (is_debug_section(name)) {
83 if (ecp->strip == STRIP_ALL ||
84 ecp->strip == STRIP_DEBUG ||
85 ecp->strip == STRIP_UNNEEDED ||
86 (ecp->flags & DISCARD_LOCAL))
88 if (ecp->strip == STRIP_NONDEBUG)
92 if ((ecp->flags & SEC_REMOVE) || (ecp->flags & SEC_COPY)) {
93 struct sec_action *sac;
95 sac = lookup_sec_act(ecp, name, 0);
96 if ((ecp->flags & SEC_REMOVE) && sac != NULL && sac->remove)
98 if ((ecp->flags & SEC_COPY) && (sac == NULL || !sac->copy))
106 * Relocation section needs to be removed if the section it applies to
110 is_remove_reloc_sec(struct elfcopy *ecp, uint32_t sh_info)
118 if (elf_getshstrndx(ecp->ein, &indx) == 0)
119 errx(EXIT_FAILURE, "elf_getshstrndx failed: %s",
123 while ((is = elf_nextscn(ecp->ein, is)) != NULL) {
124 if (sh_info == elf_ndxscn(is)) {
125 if (gelf_getshdr(is, &ish) == NULL)
126 errx(EXIT_FAILURE, "gelf_getshdr failed: %s",
128 if ((name = elf_strptr(ecp->ein, indx, ish.sh_name)) ==
130 errx(EXIT_FAILURE, "elf_strptr failed: %s",
132 if (is_remove_section(ecp, name))
138 elferr = elf_errno();
140 errx(EXIT_FAILURE, "elf_nextscn failed: %s",
143 /* Remove reloc section if we can't find the target section. */
148 is_append_section(struct elfcopy *ecp, const char *name)
150 struct sec_action *sac;
152 sac = lookup_sec_act(ecp, name, 0);
153 if (sac != NULL && sac->append != 0 && sac->string != NULL)
160 is_compress_section(struct elfcopy *ecp, const char *name)
162 struct sec_action *sac;
164 sac = lookup_sec_act(ecp, name, 0);
165 if (sac != NULL && sac->compress != 0)
172 check_section_rename(struct elfcopy *ecp, struct section *s)
174 struct sec_action *sac;
181 sac = lookup_sec_act(ecp, s->name, 0);
182 if (sac != NULL && sac->rename)
183 s->name = sac->newname;
185 if (!strcmp(s->name, ".symtab") ||
186 !strcmp(s->name, ".strtab") ||
187 !strcmp(s->name, ".shstrtab"))
191 if (s->loadable && ecp->prefix_alloc != NULL)
192 prefix = ecp->prefix_alloc;
193 else if (ecp->prefix_sec != NULL)
194 prefix = ecp->prefix_sec;
196 if (prefix != NULL) {
197 namelen = strlen(s->name) + strlen(prefix) + 1;
198 if ((s->newname = malloc(namelen)) == NULL)
199 err(EXIT_FAILURE, "malloc failed");
200 snprintf(s->newname, namelen, "%s%s", prefix, s->name);
201 s->name = s->newname;
206 get_section_flags(struct elfcopy *ecp, const char *name)
208 struct sec_action *sac;
210 sac = lookup_sec_act(ecp, name, 0);
211 if (sac != NULL && sac->flags)
218 * Determine whether the section are debugging section.
219 * According to libbfd, debugging sections are recognized
223 is_debug_section(const char *name)
225 const char *dbg_sec[] = {
235 for(p = dbg_sec; *p; p++) {
236 if (strncmp(name, *p, strlen(*p)) == 0)
244 is_dwo_section(const char *name)
248 if ((len = strlen(name)) > 4 && strcmp(name + len - 4, ".dwo") == 0)
254 is_print_section(struct elfcopy *ecp, const char *name)
256 struct sec_action *sac;
258 sac = lookup_sec_act(ecp, name, 0);
259 if (sac != NULL && sac->print != 0)
266 is_modify_section(struct elfcopy *ecp, const char *name)
269 if (is_append_section(ecp, name) ||
270 is_compress_section(ecp, name))
277 lookup_sec_act(struct elfcopy *ecp, const char *name, int add)
279 struct sec_action *sac;
284 STAILQ_FOREACH(sac, &ecp->v_sac, sac_list) {
285 if (strcmp(name, sac->name) == 0)
292 if ((sac = malloc(sizeof(*sac))) == NULL)
293 errx(EXIT_FAILURE, "not enough memory");
294 memset(sac, 0, sizeof(*sac));
296 STAILQ_INSERT_TAIL(&ecp->v_sac, sac, sac_list);
302 free_sec_act(struct elfcopy *ecp)
304 struct sec_action *sac, *sac_temp;
306 STAILQ_FOREACH_SAFE(sac, &ecp->v_sac, sac_list, sac_temp) {
307 STAILQ_REMOVE(&ecp->v_sac, sac, sec_action, sac_list);
313 insert_to_sec_list(struct elfcopy *ecp, struct section *sec, int tail)
318 TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
319 if (sec->off < s->off) {
320 TAILQ_INSERT_BEFORE(s, sec, sec_list);
326 TAILQ_INSERT_TAIL(&ecp->v_sec, sec, sec_list);
329 if (sec->pseudo == 0)
334 * First step of section creation: create scn and internal section
335 * structure, discard sections to be removed.
338 create_scn(struct elfcopy *ecp)
345 uint64_t oldndx, newndx;
346 int elferr, sec_flags, reorder;
349 * Insert a pseudo section that contains the ELF header
350 * and program header. Used as reference for section offset
351 * or load address adjustment.
353 if ((s = calloc(1, sizeof(*s))) == NULL)
354 err(EXIT_FAILURE, "calloc failed");
356 s->sz = gelf_fsize(ecp->eout, ELF_T_EHDR, 1, EV_CURRENT) +
357 gelf_fsize(ecp->eout, ELF_T_PHDR, ecp->ophnum, EV_CURRENT);
360 s->loadable = add_to_inseg_list(ecp, s);
361 insert_to_sec_list(ecp, s, 0);
363 /* Create internal .shstrtab section. */
366 if (elf_getshstrndx(ecp->ein, &indx) == 0)
367 errx(EXIT_FAILURE, "elf_getshstrndx failed: %s",
372 while ((is = elf_nextscn(ecp->ein, is)) != NULL) {
373 if (gelf_getshdr(is, &ish) == NULL)
374 errx(EXIT_FAILURE, "gelf_getshdr failed: %s",
376 if ((name = elf_strptr(ecp->ein, indx, ish.sh_name)) == NULL)
377 errx(EXIT_FAILURE, "elf_strptr failed: %s",
380 /* Skip sections to be removed. */
381 if (is_remove_section(ecp, name))
385 * Relocation section need to be remove if the section
386 * it applies will be removed.
388 if (ish.sh_type == SHT_REL || ish.sh_type == SHT_RELA)
389 if (ish.sh_info != 0 &&
390 is_remove_reloc_sec(ecp, ish.sh_info))
394 * Section groups should be removed if symbol table will
395 * be removed. (section group's signature stored in symbol
398 if (ish.sh_type == SHT_GROUP && ecp->strip == STRIP_ALL)
401 /* Get section flags set by user. */
402 sec_flags = get_section_flags(ecp, name);
404 /* Create internal section object. */
405 if (strcmp(name, ".shstrtab") != 0) {
406 if ((s = calloc(1, sizeof(*s))) == NULL)
407 err(EXIT_FAILURE, "calloc failed");
410 s->off = ish.sh_offset;
412 s->align = ish.sh_addralign;
413 s->type = ish.sh_type;
414 s->flags = ish.sh_flags;
415 s->vma = ish.sh_addr;
418 * Search program headers to determine whether section
419 * is loadable, but if user explicitly set section flags
420 * while neither "load" nor "alloc" is set, we make the
421 * section unloadable.
423 * Sections in relocatable object is loadable if
424 * section flag SHF_ALLOC is set.
427 (sec_flags & (SF_LOAD | SF_ALLOC)) == 0)
430 s->loadable = add_to_inseg_list(ecp, s);
431 if ((ecp->flags & RELOCATABLE) &&
432 (ish.sh_flags & SHF_ALLOC))
436 /* Assuming .shstrtab is "unloadable". */
438 s->off = ish.sh_offset;
441 oldndx = newndx = SHN_UNDEF;
442 if (strcmp(name, ".symtab") != 0 &&
443 strcmp(name, ".strtab") != 0) {
444 if (!strcmp(name, ".shstrtab")) {
446 * Add sections specified by --add-section and
447 * gnu debuglink. we want these sections have
448 * smaller index than .shstrtab section.
450 if (ecp->debuglink != NULL)
451 add_gnu_debuglink(ecp);
452 if (ecp->flags & SEC_ADD)
453 insert_sections(ecp);
455 if ((s->os = elf_newscn(ecp->eout)) == NULL)
456 errx(EXIT_FAILURE, "elf_newscn failed: %s",
458 if ((newndx = elf_ndxscn(s->os)) == SHN_UNDEF)
459 errx(EXIT_FAILURE, "elf_ndxscn failed: %s",
462 if ((oldndx = elf_ndxscn(is)) == SHN_UNDEF)
463 errx(EXIT_FAILURE, "elf_ndxscn failed: %s",
465 if (oldndx != SHN_UNDEF && newndx != SHN_UNDEF)
466 ecp->secndx[oldndx] = newndx;
469 * If strip action is STRIP_NONDEBUG(only keep debug),
470 * change sections type of loadable sections and section
471 * groups to SHT_NOBITS, and the content of those sections
472 * will be discarded. However, SHT_NOTE sections should
475 if (ecp->strip == STRIP_NONDEBUG) {
476 if (((ish.sh_flags & SHF_ALLOC) ||
477 (ish.sh_flags & SHF_GROUP)) &&
478 ish.sh_type != SHT_NOTE)
479 s->type = SHT_NOBITS;
482 check_section_rename(ecp, s);
484 /* create section header based on input object. */
485 if (strcmp(name, ".symtab") != 0 &&
486 strcmp(name, ".strtab") != 0 &&
487 strcmp(name, ".shstrtab") != 0) {
488 copy_shdr(ecp, s, NULL, 0, sec_flags);
490 * elfcopy puts .symtab, .strtab and .shstrtab
491 * sections in the end of the output object.
492 * If the input objects have more sections
493 * after any of these 3 sections, the section
494 * table will be reordered. section symbols
495 * should be regenerated for relocations.
498 ecp->flags &= ~SYMTAB_INTACT;
502 if (strcmp(name, ".symtab") == 0) {
503 ecp->flags |= SYMTAB_EXIST;
506 if (strcmp(name, ".strtab") == 0)
509 insert_to_sec_list(ecp, s, 0);
511 elferr = elf_errno();
513 errx(EXIT_FAILURE, "elf_nextscn failed: %s",
518 insert_shtab(struct elfcopy *ecp, int tail)
520 struct section *s, *shtab;
525 * Treat section header table as a "pseudo" section, insert it
526 * into section list, so later it will get sorted and resynced
527 * just as normal sections.
529 if ((shtab = calloc(1, sizeof(*shtab))) == NULL)
530 errx(EXIT_FAILURE, "calloc failed");
533 * "shoff" of input object is used as a hint for section
536 if (gelf_getehdr(ecp->ein, &ieh) == NULL)
537 errx(EXIT_FAILURE, "gelf_getehdr() failed: %s",
539 shtab->off = ieh.e_shoff;
542 /* Calculate number of sections in the output object. */
544 TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
548 /* Remember there is always a null section, so we +1 here. */
549 shtab->sz = gelf_fsize(ecp->eout, ELF_T_SHDR, nsecs + 1, EV_CURRENT);
551 errx(EXIT_FAILURE, "gelf_fsize() failed: %s", elf_errmsg(-1));
552 shtab->align = (ecp->oec == ELFCLASS32 ? 4 : 8);
555 insert_to_sec_list(ecp, shtab, tail);
561 copy_content(struct elfcopy *ecp)
565 TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
566 /* Skip pseudo section. */
570 /* Skip special sections. */
571 if (strcmp(s->name, ".symtab") == 0 ||
572 strcmp(s->name, ".strtab") == 0 ||
573 strcmp(s->name, ".shstrtab") == 0)
577 * If strip action is STRIP_ALL, relocation info need
578 * to be stripped. Skip filtering otherwisw.
580 if (ecp->strip == STRIP_ALL &&
581 (s->type == SHT_REL || s->type == SHT_RELA))
582 filter_reloc(ecp, s);
585 * The section indices in the SHT_GROUP section needs
586 * to be updated since we might have stripped some
587 * sections and changed section numbering.
589 if (s->type == SHT_GROUP)
590 update_section_group(ecp, s);
592 if (is_modify_section(ecp, s->name))
593 modify_section(ecp, s);
598 * If symbol table is modified, relocation info might
599 * need update, as symbol index may have changed.
601 if ((ecp->flags & SYMTAB_INTACT) == 0 &&
602 (ecp->flags & SYMTAB_EXIST) &&
603 (s->type == SHT_REL || s->type == SHT_RELA))
604 update_reloc(ecp, s);
606 if (is_print_section(ecp, s->name))
613 * Update section group section. The section indices in the SHT_GROUP
614 * section need update after section numbering changed.
617 update_section_group(struct elfcopy *ecp, struct section *s)
626 if (!elf_getshnum(ecp->ein, &ishnum))
627 errx(EXIT_FAILURE, "elf_getshnum failed: %s",
630 if (gelf_getshdr(s->is, &ish) == NULL)
631 errx(EXIT_FAILURE, "gelf_getehdr() failed: %s",
634 if ((id = elf_getdata(s->is, NULL)) == NULL)
635 errx(EXIT_FAILURE, "elf_getdata() failed: %s",
638 if (ish.sh_size == 0)
641 if (ish.sh_entsize == 0)
646 /* We only support COMDAT section. */
648 #define GRP_COMDAT 0x1
650 if ((*ws & GRP_COMDAT) == 0)
653 if ((s->buf = malloc(ish.sh_size)) == NULL)
654 err(EXIT_FAILURE, "malloc failed");
660 /* Copy the flag word as-is. */
663 /* Update the section indices. */
664 n = ish.sh_size / ish.sh_entsize;
665 for(i = 1, j = 1; (uint64_t)i < n; i++) {
666 if (ws[i] != SHN_UNDEF && ws[i] < ishnum &&
667 ecp->secndx[ws[i]] != 0)
668 wd[j++] = ecp->secndx[ws[i]];
677 * Filter relocation entries, only keep those entries whose
678 * symbol is in the keep list.
681 filter_reloc(struct elfcopy *ecp, struct section *s)
692 uint64_t cap, n, nrels, sym;
695 if (gelf_getshdr(s->is, &ish) == NULL)
696 errx(EXIT_FAILURE, "gelf_getehdr() failed: %s",
699 /* We don't want to touch relocation info for dynamic symbols. */
700 if ((ecp->flags & SYMTAB_EXIST) == 0) {
702 * No symbol table in output. If sh_link points to a section
703 * that exists in the output object, this relocation section
704 * is for dynamic symbols. Don't touch it.
706 if (ish.sh_link != 0 && ecp->secndx[ish.sh_link] != 0)
709 /* Symbol table exist, check if index equals. */
710 if (ish.sh_link != elf_ndxscn(ecp->symtab->is))
714 #define COPYREL(REL, SZ) do { \
716 if ((REL##SZ = malloc(cap * \
717 sizeof(*REL##SZ))) == NULL) \
718 err(EXIT_FAILURE, "malloc failed"); \
720 if (nrels >= cap) { \
722 if ((REL##SZ = realloc(REL##SZ, cap * \
723 sizeof(*REL##SZ))) == NULL) \
724 err(EXIT_FAILURE, "realloc failed"); \
726 REL##SZ[nrels].r_offset = REL.r_offset; \
727 REL##SZ[nrels].r_info = REL.r_info; \
728 if (s->type == SHT_RELA) \
729 rela##SZ[nrels].r_addend = rela.r_addend; \
734 cap = 4; /* keep list is usually small. */
739 if ((id = elf_getdata(s->is, NULL)) == NULL)
740 errx(EXIT_FAILURE, "elf_getdata() failed: %s",
742 n = ish.sh_size / ish.sh_entsize;
743 for(i = 0; (uint64_t)i < n; i++) {
744 if (s->type == SHT_REL) {
745 if (gelf_getrel(id, i, &rel) != &rel)
746 errx(EXIT_FAILURE, "gelf_getrel failed: %s",
748 sym = GELF_R_SYM(rel.r_info);
750 if (gelf_getrela(id, i, &rela) != &rela)
751 errx(EXIT_FAILURE, "gelf_getrel failed: %s",
753 sym = GELF_R_SYM(rela.r_info);
756 * If a relocation references a symbol and we are omitting
757 * either that symbol or the entire symbol table we cannot
758 * produce valid output, and so just omit the relocation.
759 * Broken output like this is generally not useful, but some
760 * uses of elfcopy/strip rely on it - for example, GCC's build
761 * process uses it to check for build reproducibility by
762 * stripping objects and comparing them.
764 * Relocations that do not reference a symbol are retained.
767 if (ish.sh_link == 0 || ecp->secndx[ish.sh_link] == 0)
769 name = elf_strptr(ecp->ein, elf_ndxscn(ecp->strtab->is),
772 errx(EXIT_FAILURE, "elf_strptr failed: %s",
774 if (lookup_symop_list(ecp, name, SYMOP_KEEP) == NULL)
777 if (ecp->oec == ELFCLASS32) {
778 if (s->type == SHT_REL)
783 if (s->type == SHT_REL)
789 elferr = elf_errno();
791 errx(EXIT_FAILURE, "elf_getdata() failed: %s",
794 if (ecp->oec == ELFCLASS32) {
795 if (s->type == SHT_REL)
800 if (s->type == SHT_REL)
805 s->sz = gelf_fsize(ecp->eout, (s->type == SHT_REL ? ELF_T_REL :
806 ELF_T_RELA), nrels, EV_CURRENT);
811 update_reloc(struct elfcopy *ecp, struct section *s)
820 #define UPDATEREL(REL) do { \
821 if (gelf_get##REL(od, i, &REL) != &REL) \
822 errx(EXIT_FAILURE, "gelf_get##REL failed: %s", \
824 REL.r_info = GELF_R_INFO(ecp->symndx[GELF_R_SYM(REL.r_info)], \
825 GELF_R_TYPE(REL.r_info)); \
826 if (!gelf_update_##REL(od, i, &REL)) \
827 errx(EXIT_FAILURE, "gelf_update_##REL failed: %s", \
833 if (gelf_getshdr(s->os, &osh) == NULL)
834 errx(EXIT_FAILURE, "gelf_getehdr() failed: %s",
836 /* Only process .symtab reloc info. */
837 if (osh.sh_link != elf_ndxscn(ecp->symtab->is))
839 if ((od = elf_getdata(s->os, NULL)) == NULL)
840 errx(EXIT_FAILURE, "elf_getdata() failed: %s",
842 n = osh.sh_size / osh.sh_entsize;
843 for(i = 0; (uint64_t)i < n; i++) {
844 if (s->type == SHT_REL)
852 pad_section(struct elfcopy *ecp, struct section *s)
857 if (s == NULL || s->pad_sz == 0)
860 if ((s->pad = malloc(s->pad_sz)) == NULL)
861 err(EXIT_FAILURE, "malloc failed");
862 memset(s->pad, ecp->fill, s->pad_sz);
864 /* Create a new Elf_Data to contain the padding bytes. */
865 if ((od = elf_newdata(s->os)) == NULL)
866 errx(EXIT_FAILURE, "elf_newdata() failed: %s",
871 od->d_type = ELF_T_BYTE;
872 od->d_size = s->pad_sz;
873 od->d_version = EV_CURRENT;
875 /* Update section header. */
876 if (gelf_getshdr(s->os, &osh) == NULL)
877 errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
879 osh.sh_size = s->sz + s->pad_sz;
880 if (!gelf_update_shdr(s->os, &osh))
881 errx(EXIT_FAILURE, "elf_update_shdr failed: %s",
886 resync_sections(struct elfcopy *ecp)
888 struct section *s, *ps;
896 TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
903 * Ignore TLS sections with load address 0 and without
904 * content. We don't need to adjust their file offset or
905 * VMA, only the size matters.
907 if (s->seg_tls != NULL && s->type == SHT_NOBITS &&
911 /* Align section offset. */
915 if (!s->loadable || (ecp->flags & RELOCATABLE))
916 s->off = roundup(off, s->align);
918 if (s->loadable && (ecp->flags & RELOCATABLE) == 0)
919 warnx("moving loadable section %s, "
920 "is this intentional?", s->name);
921 s->off = roundup(off, s->align);
924 /* Calculate next section offset. */
926 if (s->pseudo || (s->type != SHT_NOBITS && s->type != SHT_NULL))
934 /* Count padding bytes added through --pad-to. */
938 /* Update section header accordingly. */
939 if (gelf_getshdr(s->os, &osh) == NULL)
940 errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
942 osh.sh_addr = s->vma;
943 osh.sh_offset = s->off;
945 if (!gelf_update_shdr(s->os, &osh))
946 errx(EXIT_FAILURE, "elf_update_shdr failed: %s",
949 /* Add padding for previous section, if need. */
951 if (ps->pad_sz > 0) {
952 /* Apply padding added by --pad-to. */
953 pad_section(ecp, ps);
954 } else if ((ecp->flags & GAP_FILL) &&
955 (ps->off + ps->sz < s->off)) {
957 * Fill the gap between sections by padding
958 * the section with lower address.
960 ps->pad_sz = s->off - (ps->off + ps->sz);
961 pad_section(ecp, ps);
968 /* Pad the last section, if need. */
969 if (ps != NULL && ps->pad_sz > 0)
970 pad_section(ecp, ps);
974 modify_section(struct elfcopy *ecp, struct section *s)
976 struct sec_action *sac;
977 size_t srcsz, dstsz, p, len;
978 char *b, *c, *d, *src, *end;
981 src = read_section(s, &srcsz);
982 if (src == NULL || srcsz == 0) {
983 /* For empty section, we proceed if we need to append. */
984 if (!is_append_section(ecp, s->name))
988 /* Allocate buffer needed for new section data. */
990 if (is_append_section(ecp, s->name)) {
991 sac = lookup_sec_act(ecp, s->name, 0);
992 dstsz += strlen(sac->string) + 1;
994 if ((b = malloc(dstsz)) == NULL)
995 err(EXIT_FAILURE, "malloc failed");
998 /* Compress section. */
1000 if (is_compress_section(ecp, s->name)) {
1002 for(c = src; c < end;) {
1004 while(c + len < end && c[len] != '\0')
1006 if (c + len == end) {
1007 /* XXX should we warn here? */
1008 strncpy(&b[p], c, len);
1013 for (d = b; d < b + p; ) {
1014 if (strcmp(d, c) == 0) {
1021 strncpy(&b[p], c, len);
1028 memcpy(b, src, srcsz);
1032 /* Append section. */
1033 if (is_append_section(ecp, s->name)) {
1034 sac = lookup_sec_act(ecp, s->name, 0);
1035 len = strlen(sac->string);
1036 strncpy(&b[p], sac->string, len);
1046 print_data(const char *d, size_t sz)
1050 for (c = d; c < d + sz; c++) {
1059 print_section(struct section *s)
1064 if (s->buf != NULL && s->sz > 0) {
1065 print_data(s->buf, s->sz);
1068 while ((id = elf_getdata(s->is, id)) != NULL ||
1069 (id = elf_rawdata(s->is, id)) != NULL) {
1071 print_data(id->d_buf, id->d_size);
1073 elferr = elf_errno();
1075 errx(EXIT_FAILURE, "elf_getdata() failed: %s",
1076 elf_errmsg(elferr));
1082 read_section(struct section *s, size_t *size)
1092 while ((id = elf_getdata(s->is, id)) != NULL ||
1093 (id = elf_rawdata(s->is, id)) != NULL) {
1096 b = malloc(id->d_size);
1098 b = malloc(sz + id->d_size);
1100 err(EXIT_FAILURE, "malloc or realloc failed");
1102 memcpy(&b[sz], id->d_buf, id->d_size);
1105 elferr = elf_errno();
1107 errx(EXIT_FAILURE, "elf_getdata() failed: %s",
1108 elf_errmsg(elferr));
1116 copy_shdr(struct elfcopy *ecp, struct section *s, const char *name, int copy,
1121 if (gelf_getshdr(s->is, &ish) == NULL)
1122 errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
1124 if (gelf_getshdr(s->os, &osh) == NULL)
1125 errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
1129 (void) memcpy(&osh, &ish, sizeof(ish));
1131 osh.sh_type = s->type;
1132 osh.sh_addr = s->vma;
1133 osh.sh_offset = s->off;
1134 osh.sh_size = s->sz;
1135 osh.sh_link = ish.sh_link;
1136 osh.sh_info = ish.sh_info;
1137 osh.sh_addralign = s->align;
1138 osh.sh_entsize = ish.sh_entsize;
1142 if (sec_flags & SF_ALLOC)
1143 osh.sh_flags |= SHF_ALLOC;
1144 if ((sec_flags & SF_READONLY) == 0)
1145 osh.sh_flags |= SHF_WRITE;
1146 if (sec_flags & SF_CODE)
1147 osh.sh_flags |= SHF_EXECINSTR;
1148 if ((sec_flags & SF_CONTENTS) &&
1149 s->type == SHT_NOBITS && s->sz > 0) {
1151 * Convert SHT_NOBITS section to section with
1152 * (zero'ed) content on file.
1154 osh.sh_type = s->type = SHT_PROGBITS;
1155 if ((s->buf = calloc(1, s->sz)) == NULL)
1156 err(EXIT_FAILURE, "malloc failed");
1160 osh.sh_flags = ish.sh_flags;
1162 * Newer binutils as(1) emits the section flag
1163 * SHF_INFO_LINK for relocation sections. elfcopy
1164 * emits this flag in the output section if it's
1165 * missing in the input section, to remain compatible
1168 if (ish.sh_type == SHT_REL || ish.sh_type == SHT_RELA)
1169 osh.sh_flags |= SHF_INFO_LINK;
1174 add_to_shstrtab(ecp, s->name);
1176 add_to_shstrtab(ecp, name);
1178 if (!gelf_update_shdr(s->os, &osh))
1179 errx(EXIT_FAILURE, "elf_update_shdr failed: %s",
1184 copy_data(struct section *s)
1189 if (s->nocopy && s->buf == NULL)
1192 if ((id = elf_getdata(s->is, NULL)) == NULL) {
1194 if ((id = elf_rawdata(s->is, NULL)) == NULL) {
1195 elferr = elf_errno();
1197 errx(EXIT_FAILURE, "failed to read section:"
1203 if ((od = elf_newdata(s->os)) == NULL)
1204 errx(EXIT_FAILURE, "elf_newdata() failed: %s",
1208 /* Use s->buf as content if s->nocopy is set. */
1209 od->d_align = id->d_align;
1212 od->d_type = id->d_type;
1214 od->d_version = id->d_version;
1216 od->d_align = id->d_align;
1217 od->d_off = id->d_off;
1218 od->d_buf = id->d_buf;
1219 od->d_type = id->d_type;
1220 od->d_size = id->d_size;
1221 od->d_version = id->d_version;
1225 * Alignment Fixup. libelf does not allow the alignment for
1226 * Elf_Data descriptor to be set to 0. In this case we workaround
1227 * it by setting the alignment to 1.
1229 * According to the ELF ABI, alignment 0 and 1 has the same
1230 * meaning: the section has no alignment constraints.
1232 if (od->d_align == 0)
1237 create_external_section(struct elfcopy *ecp, const char *name, char *newname,
1238 void *buf, uint64_t size, uint64_t off, uint64_t stype, Elf_Type dtype,
1239 uint64_t flags, uint64_t align, uint64_t vma, int loadable)
1246 if ((os = elf_newscn(ecp->eout)) == NULL)
1247 errx(EXIT_FAILURE, "elf_newscn() failed: %s",
1249 if ((s = calloc(1, sizeof(*s))) == NULL)
1250 err(EXIT_FAILURE, "calloc failed");
1252 s->newname = newname; /* needs to be free()'ed */
1257 s->loadable = loadable;
1262 insert_to_sec_list(ecp, s, 1);
1264 if (gelf_getshdr(os, &osh) == NULL)
1265 errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
1267 osh.sh_flags = flags;
1268 osh.sh_type = s->type;
1269 osh.sh_addr = s->vma;
1270 osh.sh_addralign = s->align;
1271 if (!gelf_update_shdr(os, &osh))
1272 errx(EXIT_FAILURE, "gelf_update_shdr() failed: %s",
1274 add_to_shstrtab(ecp, name);
1276 if (buf != NULL && size != 0) {
1277 if ((od = elf_newdata(os)) == NULL)
1278 errx(EXIT_FAILURE, "elf_newdata() failed: %s",
1280 od->d_align = align;
1285 od->d_version = EV_CURRENT;
1289 * Clear SYMTAB_INTACT, as we probably need to update/add new
1290 * STT_SECTION symbols into the symbol table.
1292 ecp->flags &= ~SYMTAB_INTACT;
1298 * Insert sections specified by --add-section to the end of section list.
1301 insert_sections(struct elfcopy *ecp)
1308 /* Put these sections in the end of current list. */
1310 TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
1311 if (s->type != SHT_NOBITS && s->type != SHT_NULL)
1312 off = s->off + s->sz;
1317 STAILQ_FOREACH(sa, &ecp->v_sadd, sadd_list) {
1319 /* TODO: Add section header vma/lma, flag changes here */
1322 * The default section type for user added section is
1323 * SHT_PROGBITS. If the section name match certain patterns,
1324 * elfcopy will try to set a more appropriate section type.
1325 * However, data type is always set to ELF_T_BYTE and no
1326 * translation is performed by libelf.
1328 stype = SHT_PROGBITS;
1329 if (strcmp(sa->name, ".note") == 0 ||
1330 strncmp(sa->name, ".note.", strlen(".note.")) == 0)
1333 (void) create_external_section(ecp, sa->name, NULL, sa->content,
1334 sa->size, off, stype, ELF_T_BYTE, 0, 1, 0, 0);
1339 add_to_shstrtab(struct elfcopy *ecp, const char *name)
1344 insert_to_strtab(s, name);
1348 update_shdr(struct elfcopy *ecp, int update_link)
1354 TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
1358 if (gelf_getshdr(s->os, &osh) == NULL)
1359 errx(EXIT_FAILURE, "gelf_getshdr failed: %s",
1362 /* Find section name in string table and set sh_name. */
1363 osh.sh_name = lookup_string(ecp->shstrtab, s->name);
1366 * sh_link needs to be updated, since the index of the
1367 * linked section might have changed.
1369 if (update_link && osh.sh_link != 0)
1370 osh.sh_link = ecp->secndx[osh.sh_link];
1373 * sh_info of relocation section links to the section to which
1374 * its relocation info applies. So it may need update as well.
1376 if ((s->type == SHT_REL || s->type == SHT_RELA) &&
1378 osh.sh_info = ecp->secndx[osh.sh_info];
1381 * sh_info of SHT_GROUP section needs to point to the correct
1382 * string in the symbol table.
1384 if (s->type == SHT_GROUP && (ecp->flags & SYMTAB_EXIST) &&
1385 (ecp->flags & SYMTAB_INTACT) == 0)
1386 osh.sh_info = ecp->symndx[osh.sh_info];
1388 if (!gelf_update_shdr(s->os, &osh))
1389 errx(EXIT_FAILURE, "gelf_update_shdr() failed: %s",
1392 elferr = elf_errno();
1394 errx(EXIT_FAILURE, "elf_nextscn failed: %s",
1395 elf_errmsg(elferr));
1399 init_shstrtab(struct elfcopy *ecp)
1403 if ((ecp->shstrtab = calloc(1, sizeof(*ecp->shstrtab))) == NULL)
1404 err(EXIT_FAILURE, "calloc failed");
1406 s->name = ".shstrtab";
1411 s->type = SHT_STRTAB;
1414 insert_to_strtab(s, "");
1415 insert_to_strtab(s, ".symtab");
1416 insert_to_strtab(s, ".strtab");
1417 insert_to_strtab(s, ".shstrtab");
1421 set_shstrtab(struct elfcopy *ecp)
1429 if (s->os == NULL) {
1430 /* Input object does not contain .shstrtab section */
1431 if ((s->os = elf_newscn(ecp->eout)) == NULL)
1432 errx(EXIT_FAILURE, "elf_newscn failed: %s",
1434 insert_to_sec_list(ecp, s, 1);
1437 if (gelf_getshdr(s->os, &sh) == NULL)
1438 errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
1441 sh.sh_addralign = 1;
1442 sh.sh_offset = s->off;
1443 sh.sh_type = SHT_STRTAB;
1449 if ((data = elf_newdata(s->os)) == NULL)
1450 errx(EXIT_FAILURE, "elf_newdata() failed: %s",
1454 * If we don't have a symbol table, skip those a few bytes
1455 * which are reserved for this in the beginning of shstrtab.
1457 if (!(ecp->flags & SYMTAB_EXIST)) {
1458 s->sz -= sizeof(".symtab\0.strtab");
1459 memmove(s->buf, (char *)s->buf + sizeof(".symtab\0.strtab"),
1464 if (!gelf_update_shdr(s->os, &sh))
1465 errx(EXIT_FAILURE, "gelf_update_shdr() failed: %s",
1469 data->d_buf = s->buf;
1470 data->d_size = s->sz;
1472 data->d_type = ELF_T_BYTE;
1473 data->d_version = EV_CURRENT;
1475 if (!elf_setshstrndx(ecp->eout, elf_ndxscn(s->os)))
1476 errx(EXIT_FAILURE, "elf_setshstrndx() failed: %s",
1481 add_section(struct elfcopy *ecp, const char *arg)
1489 if ((s = strchr(arg, '=')) == NULL)
1491 "illegal format for --add-section option");
1492 if ((sa = malloc(sizeof(*sa))) == NULL)
1493 err(EXIT_FAILURE, "malloc failed");
1496 if ((sa->name = malloc(len + 1)) == NULL)
1497 err(EXIT_FAILURE, "malloc failed");
1498 strncpy(sa->name, arg, len);
1499 sa->name[len] = '\0';
1502 if (stat(fn, &sb) == -1)
1503 err(EXIT_FAILURE, "stat failed");
1504 sa->size = sb.st_size;
1506 if ((sa->content = malloc(sa->size)) == NULL)
1507 err(EXIT_FAILURE, "malloc failed");
1508 if ((fp = fopen(fn, "r")) == NULL)
1509 err(EXIT_FAILURE, "can not open %s", fn);
1510 if (fread(sa->content, 1, sa->size, fp) == 0 ||
1512 err(EXIT_FAILURE, "fread failed");
1517 STAILQ_INSERT_TAIL(&ecp->v_sadd, sa, sadd_list);
1518 ecp->flags |= SEC_ADD;
1522 free_sec_add(struct elfcopy *ecp)
1524 struct sec_add *sa, *sa_temp;
1526 STAILQ_FOREACH_SAFE(sa, &ecp->v_sadd, sadd_list, sa_temp) {
1527 STAILQ_REMOVE(&ecp->v_sadd, sa, sec_add, sadd_list);
1535 add_gnu_debuglink(struct elfcopy *ecp)
1544 if (ecp->debuglink == NULL)
1547 /* Read debug file content. */
1548 if ((sa = malloc(sizeof(*sa))) == NULL)
1549 err(EXIT_FAILURE, "malloc failed");
1550 if ((sa->name = strdup(".gnu_debuglink")) == NULL)
1551 err(EXIT_FAILURE, "strdup failed");
1552 if (stat(ecp->debuglink, &sb) == -1)
1553 err(EXIT_FAILURE, "stat failed");
1554 if (sb.st_size == 0)
1555 errx(EXIT_FAILURE, "empty debug link target %s",
1557 if ((buf = malloc(sb.st_size)) == NULL)
1558 err(EXIT_FAILURE, "malloc failed");
1559 if ((fp = fopen(ecp->debuglink, "r")) == NULL)
1560 err(EXIT_FAILURE, "can not open %s", ecp->debuglink);
1561 if (fread(buf, 1, sb.st_size, fp) == 0 ||
1563 err(EXIT_FAILURE, "fread failed");
1566 /* Calculate crc checksum. */
1567 crc = calc_crc32(buf, sb.st_size, 0xFFFFFFFF);
1570 /* Calculate section size and the offset to store crc checksum. */
1571 if ((fnbase = basename(ecp->debuglink)) == NULL)
1572 err(EXIT_FAILURE, "basename failed");
1573 crc_off = roundup(strlen(fnbase) + 1, 4);
1574 sa->size = crc_off + 4;
1576 /* Section content. */
1577 if ((sa->content = calloc(1, sa->size)) == NULL)
1578 err(EXIT_FAILURE, "malloc failed");
1579 strncpy(sa->content, fnbase, strlen(fnbase));
1580 if (ecp->oed == ELFDATA2LSB) {
1581 sa->content[crc_off] = crc & 0xFF;
1582 sa->content[crc_off + 1] = (crc >> 8) & 0xFF;
1583 sa->content[crc_off + 2] = (crc >> 16) & 0xFF;
1584 sa->content[crc_off + 3] = crc >> 24;
1586 sa->content[crc_off] = crc >> 24;
1587 sa->content[crc_off + 1] = (crc >> 16) & 0xFF;
1588 sa->content[crc_off + 2] = (crc >> 8) & 0xFF;
1589 sa->content[crc_off + 3] = crc & 0xFF;
1592 STAILQ_INSERT_TAIL(&ecp->v_sadd, sa, sadd_list);
1593 ecp->flags |= SEC_ADD;
1597 insert_to_strtab(struct section *t, const char *s)
1606 if ((t->buf = malloc(t->cap)) == NULL)
1607 err(EXIT_FAILURE, "malloc failed");
1613 for (c = b; c < b + t->sz;) {
1615 if (!append && len >= slen) {
1616 r = c + (len - slen);
1617 if (strcmp(r, s) == 0)
1619 } else if (len < slen && len != 0) {
1620 r = s + (slen - len);
1621 if (strcmp(c, r) == 0) {
1623 memmove(c, c + len + 1, t->sz - (c - b));
1631 while (t->sz + slen + 1 >= t->cap) {
1633 if ((t->buf = realloc(t->buf, t->cap)) == NULL)
1634 err(EXIT_FAILURE, "realloc failed");
1637 strncpy(&b[t->sz], s, slen);
1638 b[t->sz + slen] = '\0';
1643 lookup_string(struct section *t, const char *s)
1645 const char *b, *c, *r;
1650 for (c = b; c < b + t->sz;) {
1653 r = c + (len - slen);
1654 if (strcmp(r, s) == 0)
1663 static uint32_t crctable[256] =
1665 0x00000000L, 0x77073096L, 0xEE0E612CL, 0x990951BAL,
1666 0x076DC419L, 0x706AF48FL, 0xE963A535L, 0x9E6495A3L,
1667 0x0EDB8832L, 0x79DCB8A4L, 0xE0D5E91EL, 0x97D2D988L,
1668 0x09B64C2BL, 0x7EB17CBDL, 0xE7B82D07L, 0x90BF1D91L,
1669 0x1DB71064L, 0x6AB020F2L, 0xF3B97148L, 0x84BE41DEL,
1670 0x1ADAD47DL, 0x6DDDE4EBL, 0xF4D4B551L, 0x83D385C7L,
1671 0x136C9856L, 0x646BA8C0L, 0xFD62F97AL, 0x8A65C9ECL,
1672 0x14015C4FL, 0x63066CD9L, 0xFA0F3D63L, 0x8D080DF5L,
1673 0x3B6E20C8L, 0x4C69105EL, 0xD56041E4L, 0xA2677172L,
1674 0x3C03E4D1L, 0x4B04D447L, 0xD20D85FDL, 0xA50AB56BL,
1675 0x35B5A8FAL, 0x42B2986CL, 0xDBBBC9D6L, 0xACBCF940L,
1676 0x32D86CE3L, 0x45DF5C75L, 0xDCD60DCFL, 0xABD13D59L,
1677 0x26D930ACL, 0x51DE003AL, 0xC8D75180L, 0xBFD06116L,
1678 0x21B4F4B5L, 0x56B3C423L, 0xCFBA9599L, 0xB8BDA50FL,
1679 0x2802B89EL, 0x5F058808L, 0xC60CD9B2L, 0xB10BE924L,
1680 0x2F6F7C87L, 0x58684C11L, 0xC1611DABL, 0xB6662D3DL,
1681 0x76DC4190L, 0x01DB7106L, 0x98D220BCL, 0xEFD5102AL,
1682 0x71B18589L, 0x06B6B51FL, 0x9FBFE4A5L, 0xE8B8D433L,
1683 0x7807C9A2L, 0x0F00F934L, 0x9609A88EL, 0xE10E9818L,
1684 0x7F6A0DBBL, 0x086D3D2DL, 0x91646C97L, 0xE6635C01L,
1685 0x6B6B51F4L, 0x1C6C6162L, 0x856530D8L, 0xF262004EL,
1686 0x6C0695EDL, 0x1B01A57BL, 0x8208F4C1L, 0xF50FC457L,
1687 0x65B0D9C6L, 0x12B7E950L, 0x8BBEB8EAL, 0xFCB9887CL,
1688 0x62DD1DDFL, 0x15DA2D49L, 0x8CD37CF3L, 0xFBD44C65L,
1689 0x4DB26158L, 0x3AB551CEL, 0xA3BC0074L, 0xD4BB30E2L,
1690 0x4ADFA541L, 0x3DD895D7L, 0xA4D1C46DL, 0xD3D6F4FBL,
1691 0x4369E96AL, 0x346ED9FCL, 0xAD678846L, 0xDA60B8D0L,
1692 0x44042D73L, 0x33031DE5L, 0xAA0A4C5FL, 0xDD0D7CC9L,
1693 0x5005713CL, 0x270241AAL, 0xBE0B1010L, 0xC90C2086L,
1694 0x5768B525L, 0x206F85B3L, 0xB966D409L, 0xCE61E49FL,
1695 0x5EDEF90EL, 0x29D9C998L, 0xB0D09822L, 0xC7D7A8B4L,
1696 0x59B33D17L, 0x2EB40D81L, 0xB7BD5C3BL, 0xC0BA6CADL,
1697 0xEDB88320L, 0x9ABFB3B6L, 0x03B6E20CL, 0x74B1D29AL,
1698 0xEAD54739L, 0x9DD277AFL, 0x04DB2615L, 0x73DC1683L,
1699 0xE3630B12L, 0x94643B84L, 0x0D6D6A3EL, 0x7A6A5AA8L,
1700 0xE40ECF0BL, 0x9309FF9DL, 0x0A00AE27L, 0x7D079EB1L,
1701 0xF00F9344L, 0x8708A3D2L, 0x1E01F268L, 0x6906C2FEL,
1702 0xF762575DL, 0x806567CBL, 0x196C3671L, 0x6E6B06E7L,
1703 0xFED41B76L, 0x89D32BE0L, 0x10DA7A5AL, 0x67DD4ACCL,
1704 0xF9B9DF6FL, 0x8EBEEFF9L, 0x17B7BE43L, 0x60B08ED5L,
1705 0xD6D6A3E8L, 0xA1D1937EL, 0x38D8C2C4L, 0x4FDFF252L,
1706 0xD1BB67F1L, 0xA6BC5767L, 0x3FB506DDL, 0x48B2364BL,
1707 0xD80D2BDAL, 0xAF0A1B4CL, 0x36034AF6L, 0x41047A60L,
1708 0xDF60EFC3L, 0xA867DF55L, 0x316E8EEFL, 0x4669BE79L,
1709 0xCB61B38CL, 0xBC66831AL, 0x256FD2A0L, 0x5268E236L,
1710 0xCC0C7795L, 0xBB0B4703L, 0x220216B9L, 0x5505262FL,
1711 0xC5BA3BBEL, 0xB2BD0B28L, 0x2BB45A92L, 0x5CB36A04L,
1712 0xC2D7FFA7L, 0xB5D0CF31L, 0x2CD99E8BL, 0x5BDEAE1DL,
1713 0x9B64C2B0L, 0xEC63F226L, 0x756AA39CL, 0x026D930AL,
1714 0x9C0906A9L, 0xEB0E363FL, 0x72076785L, 0x05005713L,
1715 0x95BF4A82L, 0xE2B87A14L, 0x7BB12BAEL, 0x0CB61B38L,
1716 0x92D28E9BL, 0xE5D5BE0DL, 0x7CDCEFB7L, 0x0BDBDF21L,
1717 0x86D3D2D4L, 0xF1D4E242L, 0x68DDB3F8L, 0x1FDA836EL,
1718 0x81BE16CDL, 0xF6B9265BL, 0x6FB077E1L, 0x18B74777L,
1719 0x88085AE6L, 0xFF0F6A70L, 0x66063BCAL, 0x11010B5CL,
1720 0x8F659EFFL, 0xF862AE69L, 0x616BFFD3L, 0x166CCF45L,
1721 0xA00AE278L, 0xD70DD2EEL, 0x4E048354L, 0x3903B3C2L,
1722 0xA7672661L, 0xD06016F7L, 0x4969474DL, 0x3E6E77DBL,
1723 0xAED16A4AL, 0xD9D65ADCL, 0x40DF0B66L, 0x37D83BF0L,
1724 0xA9BCAE53L, 0xDEBB9EC5L, 0x47B2CF7FL, 0x30B5FFE9L,
1725 0xBDBDF21CL, 0xCABAC28AL, 0x53B39330L, 0x24B4A3A6L,
1726 0xBAD03605L, 0xCDD70693L, 0x54DE5729L, 0x23D967BFL,
1727 0xB3667A2EL, 0xC4614AB8L, 0x5D681B02L, 0x2A6F2B94L,
1728 0xB40BBE37L, 0xC30C8EA1L, 0x5A05DF1BL, 0x2D02EF8DL
1732 calc_crc32(const char *p, size_t len, uint32_t crc)
1736 for (i = 0; i < len; i++) {
1737 crc = crctable[(crc ^ *p++) & 0xFFL] ^ (crc >> 8);
1740 return (crc ^ 0xFFFFFFFF);