freebsd-dev/contrib/elftoolchain/elfcopy/sections.c
Mark Johnston b027d6545b Pass the right sizes to malloc() and realloc().
Reported by:	scan-build, via Mark Millard
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D16180
2018-07-12 18:48:53 +00:00

1727 lines
43 KiB
C

/*-
* Copyright (c) 2007-2011,2014 Kai Wang
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <err.h>
#include <libgen.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "elfcopy.h"
ELFTC_VCSID("$Id: sections.c 3443 2016-04-15 18:57:54Z kaiwang27 $");
static void add_gnu_debuglink(struct elfcopy *ecp);
static uint32_t calc_crc32(const char *p, size_t len, uint32_t crc);
static void check_section_rename(struct elfcopy *ecp, struct section *s);
static void filter_reloc(struct elfcopy *ecp, struct section *s);
static int get_section_flags(struct elfcopy *ecp, const char *name);
static void insert_sections(struct elfcopy *ecp);
static void insert_to_strtab(struct section *t, const char *s);
static int is_append_section(struct elfcopy *ecp, const char *name);
static int is_compress_section(struct elfcopy *ecp, const char *name);
static int is_debug_section(const char *name);
static int is_dwo_section(const char *name);
static int is_modify_section(struct elfcopy *ecp, const char *name);
static int is_print_section(struct elfcopy *ecp, const char *name);
static int lookup_string(struct section *t, const char *s);
static void modify_section(struct elfcopy *ecp, struct section *s);
static void pad_section(struct elfcopy *ecp, struct section *s);
static void print_data(const char *d, size_t sz);
static void print_section(struct section *s);
static void *read_section(struct section *s, size_t *size);
static void update_reloc(struct elfcopy *ecp, struct section *s);
static void update_section_group(struct elfcopy *ecp, struct section *s);
int
is_remove_section(struct elfcopy *ecp, const char *name)
{
/* Always keep section name table */
if (strcmp(name, ".shstrtab") == 0)
return 0;
if (strcmp(name, ".symtab") == 0 ||
strcmp(name, ".strtab") == 0) {
if (ecp->strip == STRIP_ALL && lookup_symop_list(
ecp, NULL, SYMOP_KEEP) == NULL)
return (1);
else
return (0);
}
if (ecp->strip == STRIP_DWO && is_dwo_section(name))
return (1);
if (ecp->strip == STRIP_NONDWO && !is_dwo_section(name))
return (1);
if (is_debug_section(name)) {
if (ecp->strip == STRIP_ALL ||
ecp->strip == STRIP_DEBUG ||
ecp->strip == STRIP_UNNEEDED ||
(ecp->flags & DISCARD_LOCAL))
return (1);
if (ecp->strip == STRIP_NONDEBUG)
return (0);
}
if ((ecp->flags & SEC_REMOVE) || (ecp->flags & SEC_COPY)) {
struct sec_action *sac;
sac = lookup_sec_act(ecp, name, 0);
if ((ecp->flags & SEC_REMOVE) && sac != NULL && sac->remove)
return (1);
if ((ecp->flags & SEC_COPY) && (sac == NULL || !sac->copy))
return (1);
}
return (0);
}
/*
* Relocation section needs to be removed if the section it applies to
* will be removed.
*/
int
is_remove_reloc_sec(struct elfcopy *ecp, uint32_t sh_info)
{
const char *name;
GElf_Shdr ish;
Elf_Scn *is;
size_t indx;
int elferr;
if (elf_getshstrndx(ecp->ein, &indx) == 0)
errx(EXIT_FAILURE, "elf_getshstrndx failed: %s",
elf_errmsg(-1));
is = NULL;
while ((is = elf_nextscn(ecp->ein, is)) != NULL) {
if (sh_info == elf_ndxscn(is)) {
if (gelf_getshdr(is, &ish) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr failed: %s",
elf_errmsg(-1));
if ((name = elf_strptr(ecp->ein, indx, ish.sh_name)) ==
NULL)
errx(EXIT_FAILURE, "elf_strptr failed: %s",
elf_errmsg(-1));
if (is_remove_section(ecp, name))
return (1);
else
return (0);
}
}
elferr = elf_errno();
if (elferr != 0)
errx(EXIT_FAILURE, "elf_nextscn failed: %s",
elf_errmsg(elferr));
/* Remove reloc section if we can't find the target section. */
return (1);
}
static int
is_append_section(struct elfcopy *ecp, const char *name)
{
struct sec_action *sac;
sac = lookup_sec_act(ecp, name, 0);
if (sac != NULL && sac->append != 0 && sac->string != NULL)
return (1);
return (0);
}
static int
is_compress_section(struct elfcopy *ecp, const char *name)
{
struct sec_action *sac;
sac = lookup_sec_act(ecp, name, 0);
if (sac != NULL && sac->compress != 0)
return (1);
return (0);
}
static void
check_section_rename(struct elfcopy *ecp, struct section *s)
{
struct sec_action *sac;
char *prefix;
size_t namelen;
if (s->pseudo)
return;
sac = lookup_sec_act(ecp, s->name, 0);
if (sac != NULL && sac->rename)
s->name = sac->newname;
if (!strcmp(s->name, ".symtab") ||
!strcmp(s->name, ".strtab") ||
!strcmp(s->name, ".shstrtab"))
return;
prefix = NULL;
if (s->loadable && ecp->prefix_alloc != NULL)
prefix = ecp->prefix_alloc;
else if (ecp->prefix_sec != NULL)
prefix = ecp->prefix_sec;
if (prefix != NULL) {
namelen = strlen(s->name) + strlen(prefix) + 1;
if ((s->newname = malloc(namelen)) == NULL)
err(EXIT_FAILURE, "malloc failed");
snprintf(s->newname, namelen, "%s%s", prefix, s->name);
s->name = s->newname;
}
}
static int
get_section_flags(struct elfcopy *ecp, const char *name)
{
struct sec_action *sac;
sac = lookup_sec_act(ecp, name, 0);
if (sac != NULL && sac->flags)
return sac->flags;
return (0);
}
/*
* Determine whether the section are debugging section.
* According to libbfd, debugging sections are recognized
* only by name.
*/
static int
is_debug_section(const char *name)
{
const char *dbg_sec[] = {
".apple_",
".debug",
".gnu.linkonce.wi.",
".line",
".stab",
NULL
};
const char **p;
for(p = dbg_sec; *p; p++) {
if (strncmp(name, *p, strlen(*p)) == 0)
return (1);
}
return (0);
}
static int
is_dwo_section(const char *name)
{
size_t len;
if ((len = strlen(name)) > 4 && strcmp(name + len - 4, ".dwo") == 0)
return (1);
return (0);
}
static int
is_print_section(struct elfcopy *ecp, const char *name)
{
struct sec_action *sac;
sac = lookup_sec_act(ecp, name, 0);
if (sac != NULL && sac->print != 0)
return (1);
return (0);
}
static int
is_modify_section(struct elfcopy *ecp, const char *name)
{
if (is_append_section(ecp, name) ||
is_compress_section(ecp, name))
return (1);
return (0);
}
struct sec_action*
lookup_sec_act(struct elfcopy *ecp, const char *name, int add)
{
struct sec_action *sac;
if (name == NULL)
return NULL;
STAILQ_FOREACH(sac, &ecp->v_sac, sac_list) {
if (strcmp(name, sac->name) == 0)
return sac;
}
if (add == 0)
return NULL;
if ((sac = malloc(sizeof(*sac))) == NULL)
errx(EXIT_FAILURE, "not enough memory");
memset(sac, 0, sizeof(*sac));
sac->name = name;
STAILQ_INSERT_TAIL(&ecp->v_sac, sac, sac_list);
return (sac);
}
void
free_sec_act(struct elfcopy *ecp)
{
struct sec_action *sac, *sac_temp;
STAILQ_FOREACH_SAFE(sac, &ecp->v_sac, sac_list, sac_temp) {
STAILQ_REMOVE(&ecp->v_sac, sac, sec_action, sac_list);
free(sac);
}
}
void
insert_to_sec_list(struct elfcopy *ecp, struct section *sec, int tail)
{
struct section *s;
if (!tail) {
TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
if (sec->off < s->off) {
TAILQ_INSERT_BEFORE(s, sec, sec_list);
goto inc_nos;
}
}
}
TAILQ_INSERT_TAIL(&ecp->v_sec, sec, sec_list);
inc_nos:
if (sec->pseudo == 0)
ecp->nos++;
}
/*
* First step of section creation: create scn and internal section
* structure, discard sections to be removed.
*/
void
create_scn(struct elfcopy *ecp)
{
struct section *s;
const char *name;
Elf_Scn *is;
GElf_Shdr ish;
size_t indx;
uint64_t oldndx, newndx;
int elferr, sec_flags, reorder;
/*
* Insert a pseudo section that contains the ELF header
* and program header. Used as reference for section offset
* or load address adjustment.
*/
if ((s = calloc(1, sizeof(*s))) == NULL)
err(EXIT_FAILURE, "calloc failed");
s->off = 0;
s->sz = gelf_fsize(ecp->eout, ELF_T_EHDR, 1, EV_CURRENT) +
gelf_fsize(ecp->eout, ELF_T_PHDR, ecp->ophnum, EV_CURRENT);
s->align = 1;
s->pseudo = 1;
s->loadable = add_to_inseg_list(ecp, s);
insert_to_sec_list(ecp, s, 0);
/* Create internal .shstrtab section. */
init_shstrtab(ecp);
if (elf_getshstrndx(ecp->ein, &indx) == 0)
errx(EXIT_FAILURE, "elf_getshstrndx failed: %s",
elf_errmsg(-1));
reorder = 0;
is = NULL;
while ((is = elf_nextscn(ecp->ein, is)) != NULL) {
if (gelf_getshdr(is, &ish) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr failed: %s",
elf_errmsg(-1));
if ((name = elf_strptr(ecp->ein, indx, ish.sh_name)) == NULL)
errx(EXIT_FAILURE, "elf_strptr failed: %s",
elf_errmsg(-1));
/* Skip sections to be removed. */
if (is_remove_section(ecp, name))
continue;
/*
* Relocation section need to be remove if the section
* it applies will be removed.
*/
if (ish.sh_type == SHT_REL || ish.sh_type == SHT_RELA)
if (ish.sh_info != 0 &&
is_remove_reloc_sec(ecp, ish.sh_info))
continue;
/*
* Section groups should be removed if symbol table will
* be removed. (section group's signature stored in symbol
* table)
*/
if (ish.sh_type == SHT_GROUP && ecp->strip == STRIP_ALL)
continue;
/* Get section flags set by user. */
sec_flags = get_section_flags(ecp, name);
/* Create internal section object. */
if (strcmp(name, ".shstrtab") != 0) {
if ((s = calloc(1, sizeof(*s))) == NULL)
err(EXIT_FAILURE, "calloc failed");
s->name = name;
s->is = is;
s->off = ish.sh_offset;
s->sz = ish.sh_size;
s->align = ish.sh_addralign;
s->type = ish.sh_type;
s->flags = ish.sh_flags;
s->vma = ish.sh_addr;
/*
* Search program headers to determine whether section
* is loadable, but if user explicitly set section flags
* while neither "load" nor "alloc" is set, we make the
* section unloadable.
*
* Sections in relocatable object is loadable if
* section flag SHF_ALLOC is set.
*/
if (sec_flags &&
(sec_flags & (SF_LOAD | SF_ALLOC)) == 0)
s->loadable = 0;
else {
s->loadable = add_to_inseg_list(ecp, s);
if ((ecp->flags & RELOCATABLE) &&
(ish.sh_flags & SHF_ALLOC))
s->loadable = 1;
}
} else {
/* Assuming .shstrtab is "unloadable". */
s = ecp->shstrtab;
s->off = ish.sh_offset;
}
oldndx = newndx = SHN_UNDEF;
if (strcmp(name, ".symtab") != 0 &&
strcmp(name, ".strtab") != 0) {
if (!strcmp(name, ".shstrtab")) {
/*
* Add sections specified by --add-section and
* gnu debuglink. we want these sections have
* smaller index than .shstrtab section.
*/
if (ecp->debuglink != NULL)
add_gnu_debuglink(ecp);
if (ecp->flags & SEC_ADD)
insert_sections(ecp);
}
if ((s->os = elf_newscn(ecp->eout)) == NULL)
errx(EXIT_FAILURE, "elf_newscn failed: %s",
elf_errmsg(-1));
if ((newndx = elf_ndxscn(s->os)) == SHN_UNDEF)
errx(EXIT_FAILURE, "elf_ndxscn failed: %s",
elf_errmsg(-1));
}
if ((oldndx = elf_ndxscn(is)) == SHN_UNDEF)
errx(EXIT_FAILURE, "elf_ndxscn failed: %s",
elf_errmsg(-1));
if (oldndx != SHN_UNDEF && newndx != SHN_UNDEF)
ecp->secndx[oldndx] = newndx;
/*
* If strip action is STRIP_NONDEBUG(only keep debug),
* change sections type of loadable sections and section
* groups to SHT_NOBITS, and the content of those sections
* will be discarded. However, SHT_NOTE sections should
* be kept.
*/
if (ecp->strip == STRIP_NONDEBUG) {
if (((ish.sh_flags & SHF_ALLOC) ||
(ish.sh_flags & SHF_GROUP)) &&
ish.sh_type != SHT_NOTE)
s->type = SHT_NOBITS;
}
check_section_rename(ecp, s);
/* create section header based on input object. */
if (strcmp(name, ".symtab") != 0 &&
strcmp(name, ".strtab") != 0 &&
strcmp(name, ".shstrtab") != 0) {
copy_shdr(ecp, s, NULL, 0, sec_flags);
/*
* elfcopy puts .symtab, .strtab and .shstrtab
* sections in the end of the output object.
* If the input objects have more sections
* after any of these 3 sections, the section
* table will be reordered. section symbols
* should be regenerated for relocations.
*/
if (reorder)
ecp->flags &= ~SYMTAB_INTACT;
} else
reorder = 1;
if (strcmp(name, ".symtab") == 0) {
ecp->flags |= SYMTAB_EXIST;
ecp->symtab = s;
}
if (strcmp(name, ".strtab") == 0)
ecp->strtab = s;
insert_to_sec_list(ecp, s, 0);
}
elferr = elf_errno();
if (elferr != 0)
errx(EXIT_FAILURE, "elf_nextscn failed: %s",
elf_errmsg(elferr));
}
struct section *
insert_shtab(struct elfcopy *ecp, int tail)
{
struct section *s, *shtab;
GElf_Ehdr ieh;
int nsecs;
/*
* Treat section header table as a "pseudo" section, insert it
* into section list, so later it will get sorted and resynced
* just as normal sections.
*/
if ((shtab = calloc(1, sizeof(*shtab))) == NULL)
errx(EXIT_FAILURE, "calloc failed");
if (!tail) {
/*
* "shoff" of input object is used as a hint for section
* resync later.
*/
if (gelf_getehdr(ecp->ein, &ieh) == NULL)
errx(EXIT_FAILURE, "gelf_getehdr() failed: %s",
elf_errmsg(-1));
shtab->off = ieh.e_shoff;
} else
shtab->off = 0;
/* Calculate number of sections in the output object. */
nsecs = 0;
TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
if (!s->pseudo)
nsecs++;
}
/* Remember there is always a null section, so we +1 here. */
shtab->sz = gelf_fsize(ecp->eout, ELF_T_SHDR, nsecs + 1, EV_CURRENT);
if (shtab->sz == 0)
errx(EXIT_FAILURE, "gelf_fsize() failed: %s", elf_errmsg(-1));
shtab->align = (ecp->oec == ELFCLASS32 ? 4 : 8);
shtab->loadable = 0;
shtab->pseudo = 1;
insert_to_sec_list(ecp, shtab, tail);
return (shtab);
}
void
copy_content(struct elfcopy *ecp)
{
struct section *s;
TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
/* Skip pseudo section. */
if (s->pseudo)
continue;
/* Skip special sections. */
if (strcmp(s->name, ".symtab") == 0 ||
strcmp(s->name, ".strtab") == 0 ||
strcmp(s->name, ".shstrtab") == 0)
continue;
/*
* If strip action is STRIP_ALL, relocation info need
* to be stripped. Skip filtering otherwisw.
*/
if (ecp->strip == STRIP_ALL &&
(s->type == SHT_REL || s->type == SHT_RELA))
filter_reloc(ecp, s);
/*
* The section indices in the SHT_GROUP section needs
* to be updated since we might have stripped some
* sections and changed section numbering.
*/
if (s->type == SHT_GROUP)
update_section_group(ecp, s);
if (is_modify_section(ecp, s->name))
modify_section(ecp, s);
copy_data(s);
/*
* If symbol table is modified, relocation info might
* need update, as symbol index may have changed.
*/
if ((ecp->flags & SYMTAB_INTACT) == 0 &&
(ecp->flags & SYMTAB_EXIST) &&
(s->type == SHT_REL || s->type == SHT_RELA))
update_reloc(ecp, s);
if (is_print_section(ecp, s->name))
print_section(s);
}
}
/*
* Update section group section. The section indices in the SHT_GROUP
* section need update after section numbering changed.
*/
static void
update_section_group(struct elfcopy *ecp, struct section *s)
{
GElf_Shdr ish;
Elf_Data *id;
uint32_t *ws, *wd;
uint64_t n;
size_t ishnum;
int i, j;
if (!elf_getshnum(ecp->ein, &ishnum))
errx(EXIT_FAILURE, "elf_getshnum failed: %s",
elf_errmsg(-1));
if (gelf_getshdr(s->is, &ish) == NULL)
errx(EXIT_FAILURE, "gelf_getehdr() failed: %s",
elf_errmsg(-1));
if ((id = elf_getdata(s->is, NULL)) == NULL)
errx(EXIT_FAILURE, "elf_getdata() failed: %s",
elf_errmsg(-1));
if (ish.sh_size == 0)
return;
if (ish.sh_entsize == 0)
ish.sh_entsize = 4;
ws = id->d_buf;
/* We only support COMDAT section. */
#ifndef GRP_COMDAT
#define GRP_COMDAT 0x1
#endif
if ((*ws & GRP_COMDAT) == 0)
return;
if ((s->buf = malloc(ish.sh_size)) == NULL)
err(EXIT_FAILURE, "malloc failed");
s->sz = ish.sh_size;
wd = s->buf;
/* Copy the flag word as-is. */
*wd = *ws;
/* Update the section indices. */
n = ish.sh_size / ish.sh_entsize;
for(i = 1, j = 1; (uint64_t)i < n; i++) {
if (ws[i] != SHN_UNDEF && ws[i] < ishnum &&
ecp->secndx[ws[i]] != 0)
wd[j++] = ecp->secndx[ws[i]];
else
s->sz -= 4;
}
s->nocopy = 1;
}
/*
* Filter relocation entries, only keep those entries whose
* symbol is in the keep list.
*/
static void
filter_reloc(struct elfcopy *ecp, struct section *s)
{
const char *name;
GElf_Shdr ish;
GElf_Rel rel;
GElf_Rela rela;
Elf32_Rel *rel32;
Elf64_Rel *rel64;
Elf32_Rela *rela32;
Elf64_Rela *rela64;
Elf_Data *id;
uint64_t cap, n, nrels;
int elferr, i;
if (gelf_getshdr(s->is, &ish) == NULL)
errx(EXIT_FAILURE, "gelf_getehdr() failed: %s",
elf_errmsg(-1));
/* We don't want to touch relocation info for dynamic symbols. */
if ((ecp->flags & SYMTAB_EXIST) == 0) {
if (ish.sh_link == 0 || ecp->secndx[ish.sh_link] == 0) {
/*
* This reloc section applies to the symbol table
* that was stripped, so discard whole section.
*/
s->nocopy = 1;
s->sz = 0;
}
return;
} else {
/* Symbol table exist, check if index equals. */
if (ish.sh_link != elf_ndxscn(ecp->symtab->is))
return;
}
#define COPYREL(REL, SZ) do { \
if (nrels == 0) { \
if ((REL##SZ = malloc(cap * \
sizeof(*REL##SZ))) == NULL) \
err(EXIT_FAILURE, "malloc failed"); \
} \
if (nrels >= cap) { \
cap *= 2; \
if ((REL##SZ = realloc(REL##SZ, cap * \
sizeof(*REL##SZ))) == NULL) \
err(EXIT_FAILURE, "realloc failed"); \
} \
REL##SZ[nrels].r_offset = REL.r_offset; \
REL##SZ[nrels].r_info = REL.r_info; \
if (s->type == SHT_RELA) \
rela##SZ[nrels].r_addend = rela.r_addend; \
nrels++; \
} while (0)
nrels = 0;
cap = 4; /* keep list is usually small. */
rel32 = NULL;
rel64 = NULL;
rela32 = NULL;
rela64 = NULL;
if ((id = elf_getdata(s->is, NULL)) == NULL)
errx(EXIT_FAILURE, "elf_getdata() failed: %s",
elf_errmsg(-1));
n = ish.sh_size / ish.sh_entsize;
for(i = 0; (uint64_t)i < n; i++) {
if (s->type == SHT_REL) {
if (gelf_getrel(id, i, &rel) != &rel)
errx(EXIT_FAILURE, "gelf_getrel failed: %s",
elf_errmsg(-1));
} else {
if (gelf_getrela(id, i, &rela) != &rela)
errx(EXIT_FAILURE, "gelf_getrel failed: %s",
elf_errmsg(-1));
}
name = elf_strptr(ecp->ein, elf_ndxscn(ecp->strtab->is),
GELF_R_SYM(rel.r_info));
if (name == NULL)
errx(EXIT_FAILURE, "elf_strptr failed: %s",
elf_errmsg(-1));
if (lookup_symop_list(ecp, name, SYMOP_KEEP) != NULL) {
if (ecp->oec == ELFCLASS32) {
if (s->type == SHT_REL)
COPYREL(rel, 32);
else
COPYREL(rela, 32);
} else {
if (s->type == SHT_REL)
COPYREL(rel, 64);
else
COPYREL(rela, 64);
}
}
}
elferr = elf_errno();
if (elferr != 0)
errx(EXIT_FAILURE, "elf_getdata() failed: %s",
elf_errmsg(elferr));
if (ecp->oec == ELFCLASS32) {
if (s->type == SHT_REL)
s->buf = rel32;
else
s->buf = rela32;
} else {
if (s->type == SHT_REL)
s->buf = rel64;
else
s->buf = rela64;
}
s->sz = gelf_fsize(ecp->eout, (s->type == SHT_REL ? ELF_T_REL :
ELF_T_RELA), nrels, EV_CURRENT);
s->nocopy = 1;
}
static void
update_reloc(struct elfcopy *ecp, struct section *s)
{
GElf_Shdr osh;
GElf_Rel rel;
GElf_Rela rela;
Elf_Data *od;
uint64_t n;
int i;
#define UPDATEREL(REL) do { \
if (gelf_get##REL(od, i, &REL) != &REL) \
errx(EXIT_FAILURE, "gelf_get##REL failed: %s", \
elf_errmsg(-1)); \
REL.r_info = GELF_R_INFO(ecp->symndx[GELF_R_SYM(REL.r_info)], \
GELF_R_TYPE(REL.r_info)); \
if (!gelf_update_##REL(od, i, &REL)) \
errx(EXIT_FAILURE, "gelf_update_##REL failed: %s", \
elf_errmsg(-1)); \
} while(0)
if (s->sz == 0)
return;
if (gelf_getshdr(s->os, &osh) == NULL)
errx(EXIT_FAILURE, "gelf_getehdr() failed: %s",
elf_errmsg(-1));
/* Only process .symtab reloc info. */
if (osh.sh_link != elf_ndxscn(ecp->symtab->is))
return;
if ((od = elf_getdata(s->os, NULL)) == NULL)
errx(EXIT_FAILURE, "elf_getdata() failed: %s",
elf_errmsg(-1));
n = osh.sh_size / osh.sh_entsize;
for(i = 0; (uint64_t)i < n; i++) {
if (s->type == SHT_REL)
UPDATEREL(rel);
else
UPDATEREL(rela);
}
}
static void
pad_section(struct elfcopy *ecp, struct section *s)
{
GElf_Shdr osh;
Elf_Data *od;
if (s == NULL || s->pad_sz == 0)
return;
if ((s->pad = malloc(s->pad_sz)) == NULL)
err(EXIT_FAILURE, "malloc failed");
memset(s->pad, ecp->fill, s->pad_sz);
/* Create a new Elf_Data to contain the padding bytes. */
if ((od = elf_newdata(s->os)) == NULL)
errx(EXIT_FAILURE, "elf_newdata() failed: %s",
elf_errmsg(-1));
od->d_align = 1;
od->d_off = s->sz;
od->d_buf = s->pad;
od->d_type = ELF_T_BYTE;
od->d_size = s->pad_sz;
od->d_version = EV_CURRENT;
/* Update section header. */
if (gelf_getshdr(s->os, &osh) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
elf_errmsg(-1));
osh.sh_size = s->sz + s->pad_sz;
if (!gelf_update_shdr(s->os, &osh))
errx(EXIT_FAILURE, "elf_update_shdr failed: %s",
elf_errmsg(-1));
}
void
resync_sections(struct elfcopy *ecp)
{
struct section *s, *ps;
GElf_Shdr osh;
uint64_t off;
int first;
ps = NULL;
first = 1;
off = 0;
TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
if (first) {
off = s->off;
first = 0;
}
/*
* Ignore TLS sections with load address 0 and without
* content. We don't need to adjust their file offset or
* VMA, only the size matters.
*/
if (s->seg_tls != NULL && s->type == SHT_NOBITS &&
s->off == 0)
continue;
/* Align section offset. */
if (s->align == 0)
s->align = 1;
if (off <= s->off) {
if (!s->loadable || (ecp->flags & RELOCATABLE))
s->off = roundup(off, s->align);
} else {
if (s->loadable && (ecp->flags & RELOCATABLE) == 0)
warnx("moving loadable section %s, "
"is this intentional?", s->name);
s->off = roundup(off, s->align);
}
/* Calculate next section offset. */
off = s->off;
if (s->pseudo || (s->type != SHT_NOBITS && s->type != SHT_NULL))
off += s->sz;
if (s->pseudo) {
ps = NULL;
continue;
}
/* Count padding bytes added through --pad-to. */
if (s->pad_sz > 0)
off += s->pad_sz;
/* Update section header accordingly. */
if (gelf_getshdr(s->os, &osh) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
elf_errmsg(-1));
osh.sh_addr = s->vma;
osh.sh_offset = s->off;
osh.sh_size = s->sz;
if (!gelf_update_shdr(s->os, &osh))
errx(EXIT_FAILURE, "elf_update_shdr failed: %s",
elf_errmsg(-1));
/* Add padding for previous section, if need. */
if (ps != NULL) {
if (ps->pad_sz > 0) {
/* Apply padding added by --pad-to. */
pad_section(ecp, ps);
} else if ((ecp->flags & GAP_FILL) &&
(ps->off + ps->sz < s->off)) {
/*
* Fill the gap between sections by padding
* the section with lower address.
*/
ps->pad_sz = s->off - (ps->off + ps->sz);
pad_section(ecp, ps);
}
}
ps = s;
}
/* Pad the last section, if need. */
if (ps != NULL && ps->pad_sz > 0)
pad_section(ecp, ps);
}
static void
modify_section(struct elfcopy *ecp, struct section *s)
{
struct sec_action *sac;
size_t srcsz, dstsz, p, len;
char *b, *c, *d, *src, *end;
int dupe;
src = read_section(s, &srcsz);
if (src == NULL || srcsz == 0) {
/* For empty section, we proceed if we need to append. */
if (!is_append_section(ecp, s->name))
return;
}
/* Allocate buffer needed for new section data. */
dstsz = srcsz;
if (is_append_section(ecp, s->name)) {
sac = lookup_sec_act(ecp, s->name, 0);
dstsz += strlen(sac->string) + 1;
}
if ((b = malloc(dstsz)) == NULL)
err(EXIT_FAILURE, "malloc failed");
s->buf = b;
/* Compress section. */
p = 0;
if (is_compress_section(ecp, s->name)) {
end = src + srcsz;
for(c = src; c < end;) {
len = 0;
while(c + len < end && c[len] != '\0')
len++;
if (c + len == end) {
/* XXX should we warn here? */
strncpy(&b[p], c, len);
p += len;
break;
}
dupe = 0;
for (d = b; d < b + p; ) {
if (strcmp(d, c) == 0) {
dupe = 1;
break;
}
d += strlen(d) + 1;
}
if (!dupe) {
strncpy(&b[p], c, len);
b[p + len] = '\0';
p += len + 1;
}
c += len + 1;
}
} else {
memcpy(b, src, srcsz);
p += srcsz;
}
/* Append section. */
if (is_append_section(ecp, s->name)) {
sac = lookup_sec_act(ecp, s->name, 0);
len = strlen(sac->string);
strncpy(&b[p], sac->string, len);
b[p + len] = '\0';
p += len + 1;
}
s->sz = p;
s->nocopy = 1;
}
static void
print_data(const char *d, size_t sz)
{
const char *c;
for (c = d; c < d + sz; c++) {
if (*c == '\0')
putchar('\n');
else
putchar(*c);
}
}
static void
print_section(struct section *s)
{
Elf_Data *id;
int elferr;
if (s->buf != NULL && s->sz > 0) {
print_data(s->buf, s->sz);
} else {
id = NULL;
while ((id = elf_getdata(s->is, id)) != NULL ||
(id = elf_rawdata(s->is, id)) != NULL) {
(void) elf_errno();
print_data(id->d_buf, id->d_size);
}
elferr = elf_errno();
if (elferr != 0)
errx(EXIT_FAILURE, "elf_getdata() failed: %s",
elf_errmsg(elferr));
}
putchar('\n');
}
static void *
read_section(struct section *s, size_t *size)
{
Elf_Data *id;
char *b;
size_t sz;
int elferr;
sz = 0;
b = NULL;
id = NULL;
while ((id = elf_getdata(s->is, id)) != NULL ||
(id = elf_rawdata(s->is, id)) != NULL) {
(void) elf_errno();
if (b == NULL)
b = malloc(id->d_size);
else
b = malloc(sz + id->d_size);
if (b == NULL)
err(EXIT_FAILURE, "malloc or realloc failed");
memcpy(&b[sz], id->d_buf, id->d_size);
sz += id->d_size;
}
elferr = elf_errno();
if (elferr != 0)
errx(EXIT_FAILURE, "elf_getdata() failed: %s",
elf_errmsg(elferr));
*size = sz;
return (b);
}
void
copy_shdr(struct elfcopy *ecp, struct section *s, const char *name, int copy,
int sec_flags)
{
GElf_Shdr ish, osh;
if (gelf_getshdr(s->is, &ish) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
elf_errmsg(-1));
if (gelf_getshdr(s->os, &osh) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
elf_errmsg(-1));
if (copy)
(void) memcpy(&osh, &ish, sizeof(ish));
else {
osh.sh_type = s->type;
osh.sh_addr = s->vma;
osh.sh_offset = s->off;
osh.sh_size = s->sz;
osh.sh_link = ish.sh_link;
osh.sh_info = ish.sh_info;
osh.sh_addralign = s->align;
osh.sh_entsize = ish.sh_entsize;
if (sec_flags) {
osh.sh_flags = 0;
if (sec_flags & SF_ALLOC)
osh.sh_flags |= SHF_ALLOC;
if ((sec_flags & SF_READONLY) == 0)
osh.sh_flags |= SHF_WRITE;
if (sec_flags & SF_CODE)
osh.sh_flags |= SHF_EXECINSTR;
if ((sec_flags & SF_CONTENTS) &&
s->type == SHT_NOBITS && s->sz > 0) {
/*
* Convert SHT_NOBITS section to section with
* (zero'ed) content on file.
*/
osh.sh_type = s->type = SHT_PROGBITS;
if ((s->buf = calloc(1, s->sz)) == NULL)
err(EXIT_FAILURE, "malloc failed");
s->nocopy = 1;
}
} else {
osh.sh_flags = ish.sh_flags;
/*
* Newer binutils as(1) emits the section flag
* SHF_INFO_LINK for relocation sections. elfcopy
* emits this flag in the output section if it's
* missing in the input section, to remain compatible
* with binutils.
*/
if (ish.sh_type == SHT_REL || ish.sh_type == SHT_RELA)
osh.sh_flags |= SHF_INFO_LINK;
}
}
if (name == NULL)
add_to_shstrtab(ecp, s->name);
else
add_to_shstrtab(ecp, name);
if (!gelf_update_shdr(s->os, &osh))
errx(EXIT_FAILURE, "elf_update_shdr failed: %s",
elf_errmsg(-1));
}
void
copy_data(struct section *s)
{
Elf_Data *id, *od;
int elferr;
if (s->nocopy && s->buf == NULL)
return;
if ((id = elf_getdata(s->is, NULL)) == NULL) {
(void) elf_errno();
if ((id = elf_rawdata(s->is, NULL)) == NULL) {
elferr = elf_errno();
if (elferr != 0)
errx(EXIT_FAILURE, "failed to read section:"
" %s", s->name);
return;
}
}
if ((od = elf_newdata(s->os)) == NULL)
errx(EXIT_FAILURE, "elf_newdata() failed: %s",
elf_errmsg(-1));
if (s->nocopy) {
/* Use s->buf as content if s->nocopy is set. */
od->d_align = id->d_align;
od->d_off = 0;
od->d_buf = s->buf;
od->d_type = id->d_type;
od->d_size = s->sz;
od->d_version = id->d_version;
} else {
od->d_align = id->d_align;
od->d_off = id->d_off;
od->d_buf = id->d_buf;
od->d_type = id->d_type;
od->d_size = id->d_size;
od->d_version = id->d_version;
}
/*
* Alignment Fixup. libelf does not allow the alignment for
* Elf_Data descriptor to be set to 0. In this case we workaround
* it by setting the alignment to 1.
*
* According to the ELF ABI, alignment 0 and 1 has the same
* meaning: the section has no alignment constraints.
*/
if (od->d_align == 0)
od->d_align = 1;
}
struct section *
create_external_section(struct elfcopy *ecp, const char *name, char *newname,
void *buf, uint64_t size, uint64_t off, uint64_t stype, Elf_Type dtype,
uint64_t flags, uint64_t align, uint64_t vma, int loadable)
{
struct section *s;
Elf_Scn *os;
Elf_Data *od;
GElf_Shdr osh;
if ((os = elf_newscn(ecp->eout)) == NULL)
errx(EXIT_FAILURE, "elf_newscn() failed: %s",
elf_errmsg(-1));
if ((s = calloc(1, sizeof(*s))) == NULL)
err(EXIT_FAILURE, "calloc failed");
s->name = name;
s->newname = newname; /* needs to be free()'ed */
s->off = off;
s->sz = size;
s->vma = vma;
s->align = align;
s->loadable = loadable;
s->is = NULL;
s->os = os;
s->type = stype;
s->nocopy = 1;
insert_to_sec_list(ecp, s, 1);
if (gelf_getshdr(os, &osh) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
elf_errmsg(-1));
osh.sh_flags = flags;
osh.sh_type = s->type;
osh.sh_addr = s->vma;
osh.sh_addralign = s->align;
if (!gelf_update_shdr(os, &osh))
errx(EXIT_FAILURE, "gelf_update_shdr() failed: %s",
elf_errmsg(-1));
add_to_shstrtab(ecp, name);
if (buf != NULL && size != 0) {
if ((od = elf_newdata(os)) == NULL)
errx(EXIT_FAILURE, "elf_newdata() failed: %s",
elf_errmsg(-1));
od->d_align = align;
od->d_off = 0;
od->d_buf = buf;
od->d_size = size;
od->d_type = dtype;
od->d_version = EV_CURRENT;
}
/*
* Clear SYMTAB_INTACT, as we probably need to update/add new
* STT_SECTION symbols into the symbol table.
*/
ecp->flags &= ~SYMTAB_INTACT;
return (s);
}
/*
* Insert sections specified by --add-section to the end of section list.
*/
static void
insert_sections(struct elfcopy *ecp)
{
struct sec_add *sa;
struct section *s;
size_t off;
uint64_t stype;
/* Put these sections in the end of current list. */
off = 0;
TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
if (s->type != SHT_NOBITS && s->type != SHT_NULL)
off = s->off + s->sz;
else
off = s->off;
}
STAILQ_FOREACH(sa, &ecp->v_sadd, sadd_list) {
/* TODO: Add section header vma/lma, flag changes here */
/*
* The default section type for user added section is
* SHT_PROGBITS. If the section name match certain patterns,
* elfcopy will try to set a more appropriate section type.
* However, data type is always set to ELF_T_BYTE and no
* translation is performed by libelf.
*/
stype = SHT_PROGBITS;
if (strcmp(sa->name, ".note") == 0 ||
strncmp(sa->name, ".note.", strlen(".note.")) == 0)
stype = SHT_NOTE;
(void) create_external_section(ecp, sa->name, NULL, sa->content,
sa->size, off, stype, ELF_T_BYTE, 0, 1, 0, 0);
}
}
void
add_to_shstrtab(struct elfcopy *ecp, const char *name)
{
struct section *s;
s = ecp->shstrtab;
insert_to_strtab(s, name);
}
void
update_shdr(struct elfcopy *ecp, int update_link)
{
struct section *s;
GElf_Shdr osh;
int elferr;
TAILQ_FOREACH(s, &ecp->v_sec, sec_list) {
if (s->pseudo)
continue;
if (gelf_getshdr(s->os, &osh) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr failed: %s",
elf_errmsg(-1));
/* Find section name in string table and set sh_name. */
osh.sh_name = lookup_string(ecp->shstrtab, s->name);
/*
* sh_link needs to be updated, since the index of the
* linked section might have changed.
*/
if (update_link && osh.sh_link != 0)
osh.sh_link = ecp->secndx[osh.sh_link];
/*
* sh_info of relocation section links to the section to which
* its relocation info applies. So it may need update as well.
*/
if ((s->type == SHT_REL || s->type == SHT_RELA) &&
osh.sh_info != 0)
osh.sh_info = ecp->secndx[osh.sh_info];
/*
* sh_info of SHT_GROUP section needs to point to the correct
* string in the symbol table.
*/
if (s->type == SHT_GROUP && (ecp->flags & SYMTAB_EXIST) &&
(ecp->flags & SYMTAB_INTACT) == 0)
osh.sh_info = ecp->symndx[osh.sh_info];
if (!gelf_update_shdr(s->os, &osh))
errx(EXIT_FAILURE, "gelf_update_shdr() failed: %s",
elf_errmsg(-1));
}
elferr = elf_errno();
if (elferr != 0)
errx(EXIT_FAILURE, "elf_nextscn failed: %s",
elf_errmsg(elferr));
}
void
init_shstrtab(struct elfcopy *ecp)
{
struct section *s;
if ((ecp->shstrtab = calloc(1, sizeof(*ecp->shstrtab))) == NULL)
err(EXIT_FAILURE, "calloc failed");
s = ecp->shstrtab;
s->name = ".shstrtab";
s->is = NULL;
s->sz = 0;
s->align = 1;
s->loadable = 0;
s->type = SHT_STRTAB;
s->vma = 0;
insert_to_strtab(s, "");
insert_to_strtab(s, ".symtab");
insert_to_strtab(s, ".strtab");
insert_to_strtab(s, ".shstrtab");
}
void
set_shstrtab(struct elfcopy *ecp)
{
struct section *s;
Elf_Data *data;
GElf_Shdr sh;
s = ecp->shstrtab;
if (s->os == NULL) {
/* Input object does not contain .shstrtab section */
if ((s->os = elf_newscn(ecp->eout)) == NULL)
errx(EXIT_FAILURE, "elf_newscn failed: %s",
elf_errmsg(-1));
insert_to_sec_list(ecp, s, 1);
}
if (gelf_getshdr(s->os, &sh) == NULL)
errx(EXIT_FAILURE, "gelf_getshdr() failed: %s",
elf_errmsg(-1));
sh.sh_addr = 0;
sh.sh_addralign = 1;
sh.sh_offset = s->off;
sh.sh_type = SHT_STRTAB;
sh.sh_flags = 0;
sh.sh_entsize = 0;
sh.sh_info = 0;
sh.sh_link = 0;
if ((data = elf_newdata(s->os)) == NULL)
errx(EXIT_FAILURE, "elf_newdata() failed: %s",
elf_errmsg(-1));
/*
* If we don't have a symbol table, skip those a few bytes
* which are reserved for this in the beginning of shstrtab.
*/
if (!(ecp->flags & SYMTAB_EXIST)) {
s->sz -= sizeof(".symtab\0.strtab");
memmove(s->buf, (char *)s->buf + sizeof(".symtab\0.strtab"),
s->sz);
}
sh.sh_size = s->sz;
if (!gelf_update_shdr(s->os, &sh))
errx(EXIT_FAILURE, "gelf_update_shdr() failed: %s",
elf_errmsg(-1));
data->d_align = 1;
data->d_buf = s->buf;
data->d_size = s->sz;
data->d_off = 0;
data->d_type = ELF_T_BYTE;
data->d_version = EV_CURRENT;
if (!elf_setshstrndx(ecp->eout, elf_ndxscn(s->os)))
errx(EXIT_FAILURE, "elf_setshstrndx() failed: %s",
elf_errmsg(-1));
}
void
add_section(struct elfcopy *ecp, const char *arg)
{
struct sec_add *sa;
struct stat sb;
const char *s, *fn;
FILE *fp;
int len;
if ((s = strchr(arg, '=')) == NULL)
errx(EXIT_FAILURE,
"illegal format for --add-section option");
if ((sa = malloc(sizeof(*sa))) == NULL)
err(EXIT_FAILURE, "malloc failed");
len = s - arg;
if ((sa->name = malloc(len + 1)) == NULL)
err(EXIT_FAILURE, "malloc failed");
strncpy(sa->name, arg, len);
sa->name[len] = '\0';
fn = s + 1;
if (stat(fn, &sb) == -1)
err(EXIT_FAILURE, "stat failed");
sa->size = sb.st_size;
if (sa->size > 0) {
if ((sa->content = malloc(sa->size)) == NULL)
err(EXIT_FAILURE, "malloc failed");
if ((fp = fopen(fn, "r")) == NULL)
err(EXIT_FAILURE, "can not open %s", fn);
if (fread(sa->content, 1, sa->size, fp) == 0 ||
ferror(fp))
err(EXIT_FAILURE, "fread failed");
fclose(fp);
} else
sa->content = NULL;
STAILQ_INSERT_TAIL(&ecp->v_sadd, sa, sadd_list);
ecp->flags |= SEC_ADD;
}
void
free_sec_add(struct elfcopy *ecp)
{
struct sec_add *sa, *sa_temp;
STAILQ_FOREACH_SAFE(sa, &ecp->v_sadd, sadd_list, sa_temp) {
STAILQ_REMOVE(&ecp->v_sadd, sa, sec_add, sadd_list);
free(sa->name);
free(sa->content);
free(sa);
}
}
static void
add_gnu_debuglink(struct elfcopy *ecp)
{
struct sec_add *sa;
struct stat sb;
FILE *fp;
char *fnbase, *buf;
int crc_off;
int crc;
if (ecp->debuglink == NULL)
return;
/* Read debug file content. */
if ((sa = malloc(sizeof(*sa))) == NULL)
err(EXIT_FAILURE, "malloc failed");
if ((sa->name = strdup(".gnu_debuglink")) == NULL)
err(EXIT_FAILURE, "strdup failed");
if (stat(ecp->debuglink, &sb) == -1)
err(EXIT_FAILURE, "stat failed");
if (sb.st_size == 0)
errx(EXIT_FAILURE, "empty debug link target %s",
ecp->debuglink);
if ((buf = malloc(sb.st_size)) == NULL)
err(EXIT_FAILURE, "malloc failed");
if ((fp = fopen(ecp->debuglink, "r")) == NULL)
err(EXIT_FAILURE, "can not open %s", ecp->debuglink);
if (fread(buf, 1, sb.st_size, fp) == 0 ||
ferror(fp))
err(EXIT_FAILURE, "fread failed");
fclose(fp);
/* Calculate crc checksum. */
crc = calc_crc32(buf, sb.st_size, 0xFFFFFFFF);
free(buf);
/* Calculate section size and the offset to store crc checksum. */
if ((fnbase = basename(ecp->debuglink)) == NULL)
err(EXIT_FAILURE, "basename failed");
crc_off = roundup(strlen(fnbase) + 1, 4);
sa->size = crc_off + 4;
/* Section content. */
if ((sa->content = calloc(1, sa->size)) == NULL)
err(EXIT_FAILURE, "malloc failed");
strncpy(sa->content, fnbase, strlen(fnbase));
if (ecp->oed == ELFDATA2LSB) {
sa->content[crc_off] = crc & 0xFF;
sa->content[crc_off + 1] = (crc >> 8) & 0xFF;
sa->content[crc_off + 2] = (crc >> 16) & 0xFF;
sa->content[crc_off + 3] = crc >> 24;
} else {
sa->content[crc_off] = crc >> 24;
sa->content[crc_off + 1] = (crc >> 16) & 0xFF;
sa->content[crc_off + 2] = (crc >> 8) & 0xFF;
sa->content[crc_off + 3] = crc & 0xFF;
}
STAILQ_INSERT_TAIL(&ecp->v_sadd, sa, sadd_list);
ecp->flags |= SEC_ADD;
}
static void
insert_to_strtab(struct section *t, const char *s)
{
const char *r;
char *b, *c;
size_t len, slen;
int append;
if (t->sz == 0) {
t->cap = 512;
if ((t->buf = malloc(t->cap)) == NULL)
err(EXIT_FAILURE, "malloc failed");
}
slen = strlen(s);
append = 0;
b = t->buf;
for (c = b; c < b + t->sz;) {
len = strlen(c);
if (!append && len >= slen) {
r = c + (len - slen);
if (strcmp(r, s) == 0)
return;
} else if (len < slen && len != 0) {
r = s + (slen - len);
if (strcmp(c, r) == 0) {
t->sz -= len + 1;
memmove(c, c + len + 1, t->sz - (c - b));
append = 1;
continue;
}
}
c += len + 1;
}
while (t->sz + slen + 1 >= t->cap) {
t->cap *= 2;
if ((t->buf = realloc(t->buf, t->cap)) == NULL)
err(EXIT_FAILURE, "realloc failed");
}
b = t->buf;
strncpy(&b[t->sz], s, slen);
b[t->sz + slen] = '\0';
t->sz += slen + 1;
}
static int
lookup_string(struct section *t, const char *s)
{
const char *b, *c, *r;
size_t len, slen;
slen = strlen(s);
b = t->buf;
for (c = b; c < b + t->sz;) {
len = strlen(c);
if (len >= slen) {
r = c + (len - slen);
if (strcmp(r, s) == 0)
return (r - b);
}
c += len + 1;
}
return (-1);
}
static uint32_t crctable[256] =
{
0x00000000L, 0x77073096L, 0xEE0E612CL, 0x990951BAL,
0x076DC419L, 0x706AF48FL, 0xE963A535L, 0x9E6495A3L,
0x0EDB8832L, 0x79DCB8A4L, 0xE0D5E91EL, 0x97D2D988L,
0x09B64C2BL, 0x7EB17CBDL, 0xE7B82D07L, 0x90BF1D91L,
0x1DB71064L, 0x6AB020F2L, 0xF3B97148L, 0x84BE41DEL,
0x1ADAD47DL, 0x6DDDE4EBL, 0xF4D4B551L, 0x83D385C7L,
0x136C9856L, 0x646BA8C0L, 0xFD62F97AL, 0x8A65C9ECL,
0x14015C4FL, 0x63066CD9L, 0xFA0F3D63L, 0x8D080DF5L,
0x3B6E20C8L, 0x4C69105EL, 0xD56041E4L, 0xA2677172L,
0x3C03E4D1L, 0x4B04D447L, 0xD20D85FDL, 0xA50AB56BL,
0x35B5A8FAL, 0x42B2986CL, 0xDBBBC9D6L, 0xACBCF940L,
0x32D86CE3L, 0x45DF5C75L, 0xDCD60DCFL, 0xABD13D59L,
0x26D930ACL, 0x51DE003AL, 0xC8D75180L, 0xBFD06116L,
0x21B4F4B5L, 0x56B3C423L, 0xCFBA9599L, 0xB8BDA50FL,
0x2802B89EL, 0x5F058808L, 0xC60CD9B2L, 0xB10BE924L,
0x2F6F7C87L, 0x58684C11L, 0xC1611DABL, 0xB6662D3DL,
0x76DC4190L, 0x01DB7106L, 0x98D220BCL, 0xEFD5102AL,
0x71B18589L, 0x06B6B51FL, 0x9FBFE4A5L, 0xE8B8D433L,
0x7807C9A2L, 0x0F00F934L, 0x9609A88EL, 0xE10E9818L,
0x7F6A0DBBL, 0x086D3D2DL, 0x91646C97L, 0xE6635C01L,
0x6B6B51F4L, 0x1C6C6162L, 0x856530D8L, 0xF262004EL,
0x6C0695EDL, 0x1B01A57BL, 0x8208F4C1L, 0xF50FC457L,
0x65B0D9C6L, 0x12B7E950L, 0x8BBEB8EAL, 0xFCB9887CL,
0x62DD1DDFL, 0x15DA2D49L, 0x8CD37CF3L, 0xFBD44C65L,
0x4DB26158L, 0x3AB551CEL, 0xA3BC0074L, 0xD4BB30E2L,
0x4ADFA541L, 0x3DD895D7L, 0xA4D1C46DL, 0xD3D6F4FBL,
0x4369E96AL, 0x346ED9FCL, 0xAD678846L, 0xDA60B8D0L,
0x44042D73L, 0x33031DE5L, 0xAA0A4C5FL, 0xDD0D7CC9L,
0x5005713CL, 0x270241AAL, 0xBE0B1010L, 0xC90C2086L,
0x5768B525L, 0x206F85B3L, 0xB966D409L, 0xCE61E49FL,
0x5EDEF90EL, 0x29D9C998L, 0xB0D09822L, 0xC7D7A8B4L,
0x59B33D17L, 0x2EB40D81L, 0xB7BD5C3BL, 0xC0BA6CADL,
0xEDB88320L, 0x9ABFB3B6L, 0x03B6E20CL, 0x74B1D29AL,
0xEAD54739L, 0x9DD277AFL, 0x04DB2615L, 0x73DC1683L,
0xE3630B12L, 0x94643B84L, 0x0D6D6A3EL, 0x7A6A5AA8L,
0xE40ECF0BL, 0x9309FF9DL, 0x0A00AE27L, 0x7D079EB1L,
0xF00F9344L, 0x8708A3D2L, 0x1E01F268L, 0x6906C2FEL,
0xF762575DL, 0x806567CBL, 0x196C3671L, 0x6E6B06E7L,
0xFED41B76L, 0x89D32BE0L, 0x10DA7A5AL, 0x67DD4ACCL,
0xF9B9DF6FL, 0x8EBEEFF9L, 0x17B7BE43L, 0x60B08ED5L,
0xD6D6A3E8L, 0xA1D1937EL, 0x38D8C2C4L, 0x4FDFF252L,
0xD1BB67F1L, 0xA6BC5767L, 0x3FB506DDL, 0x48B2364BL,
0xD80D2BDAL, 0xAF0A1B4CL, 0x36034AF6L, 0x41047A60L,
0xDF60EFC3L, 0xA867DF55L, 0x316E8EEFL, 0x4669BE79L,
0xCB61B38CL, 0xBC66831AL, 0x256FD2A0L, 0x5268E236L,
0xCC0C7795L, 0xBB0B4703L, 0x220216B9L, 0x5505262FL,
0xC5BA3BBEL, 0xB2BD0B28L, 0x2BB45A92L, 0x5CB36A04L,
0xC2D7FFA7L, 0xB5D0CF31L, 0x2CD99E8BL, 0x5BDEAE1DL,
0x9B64C2B0L, 0xEC63F226L, 0x756AA39CL, 0x026D930AL,
0x9C0906A9L, 0xEB0E363FL, 0x72076785L, 0x05005713L,
0x95BF4A82L, 0xE2B87A14L, 0x7BB12BAEL, 0x0CB61B38L,
0x92D28E9BL, 0xE5D5BE0DL, 0x7CDCEFB7L, 0x0BDBDF21L,
0x86D3D2D4L, 0xF1D4E242L, 0x68DDB3F8L, 0x1FDA836EL,
0x81BE16CDL, 0xF6B9265BL, 0x6FB077E1L, 0x18B74777L,
0x88085AE6L, 0xFF0F6A70L, 0x66063BCAL, 0x11010B5CL,
0x8F659EFFL, 0xF862AE69L, 0x616BFFD3L, 0x166CCF45L,
0xA00AE278L, 0xD70DD2EEL, 0x4E048354L, 0x3903B3C2L,
0xA7672661L, 0xD06016F7L, 0x4969474DL, 0x3E6E77DBL,
0xAED16A4AL, 0xD9D65ADCL, 0x40DF0B66L, 0x37D83BF0L,
0xA9BCAE53L, 0xDEBB9EC5L, 0x47B2CF7FL, 0x30B5FFE9L,
0xBDBDF21CL, 0xCABAC28AL, 0x53B39330L, 0x24B4A3A6L,
0xBAD03605L, 0xCDD70693L, 0x54DE5729L, 0x23D967BFL,
0xB3667A2EL, 0xC4614AB8L, 0x5D681B02L, 0x2A6F2B94L,
0xB40BBE37L, 0xC30C8EA1L, 0x5A05DF1BL, 0x2D02EF8DL
};
static uint32_t
calc_crc32(const char *p, size_t len, uint32_t crc)
{
uint32_t i;
for (i = 0; i < len; i++) {
crc = crctable[(crc ^ *p++) & 0xFFL] ^ (crc >> 8);
}
return (crc ^ 0xFFFFFFFF);
}