When mac_veriexec is enforcing, we won't run unverified binaries, don't let ldd examine them either. Reviewed by: stevek emaste MFC after: 1 week Sponsored by: Juniper Networks, Inc. Differential Revision: https://reviews.freebsd.org/D36897
474 lines
11 KiB
C
474 lines
11 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-4-Clause
|
|
*
|
|
* Copyright (c) 1993 Paul Kranenburg
|
|
* 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.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by Paul Kranenburg.
|
|
* 4. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/wait.h>
|
|
|
|
#include <machine/elf.h>
|
|
|
|
#include <arpa/inet.h>
|
|
|
|
#include <dlfcn.h>
|
|
#include <err.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <gelf.h>
|
|
#include <libelf.h>
|
|
#include <rtld_paths.h>
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
/*
|
|
* 32-bit ELF data structures can only be used if the system header[s] declare
|
|
* them. There is no official macro for determining whether they are declared,
|
|
* so check for the existence of one of the 32-macros defined in elf(5).
|
|
*/
|
|
#ifdef ELF32_R_TYPE
|
|
#define ELF32_SUPPORTED
|
|
#endif
|
|
|
|
#define LDD_SETENV(name, value, overwrite) do { \
|
|
setenv("LD_" name, value, overwrite); \
|
|
setenv("LD_32_" name, value, overwrite); \
|
|
} while (0)
|
|
|
|
#define LDD_UNSETENV(name) do { \
|
|
unsetenv("LD_" name); \
|
|
unsetenv("LD_32_" name); \
|
|
} while (0)
|
|
|
|
static int is_executable(const char *fname, int fd, int *is_shlib,
|
|
int *type);
|
|
static void usage(void);
|
|
|
|
#define TYPE_UNKNOWN 0
|
|
#define TYPE_ELF 1 /* Architecture default */
|
|
#if __ELF_WORD_SIZE > 32 && defined(ELF32_SUPPORTED)
|
|
#define TYPE_ELF32 2 /* Explicit 32 bits on architectures >32 bits */
|
|
|
|
#define _PATH_LDD32 "/usr/bin/ldd32"
|
|
|
|
static int
|
|
execldd32(char *file, char *fmt1, char *fmt2, int aflag)
|
|
{
|
|
char *argv[9];
|
|
int i, rval, status;
|
|
|
|
LDD_UNSETENV("TRACE_LOADED_OBJECTS");
|
|
rval = 0;
|
|
i = 0;
|
|
argv[i++] = strdup(_PATH_LDD32);
|
|
if (aflag)
|
|
argv[i++] = strdup("-a");
|
|
if (fmt1 != NULL) {
|
|
argv[i++] = strdup("-f");
|
|
argv[i++] = strdup(fmt1);
|
|
}
|
|
if (fmt2 != NULL) {
|
|
argv[i++] = strdup("-f");
|
|
argv[i++] = strdup(fmt2);
|
|
}
|
|
argv[i++] = strdup(file);
|
|
argv[i++] = NULL;
|
|
|
|
switch (fork()) {
|
|
case -1:
|
|
err(1, "fork");
|
|
break;
|
|
case 0:
|
|
execv(_PATH_LDD32, argv);
|
|
warn("%s", _PATH_LDD32);
|
|
_exit(127);
|
|
break;
|
|
default:
|
|
if (wait(&status) < 0)
|
|
rval = 1;
|
|
else if (WIFSIGNALED(status))
|
|
rval = 1;
|
|
else if (WIFEXITED(status) && WEXITSTATUS(status) != 0)
|
|
rval = 1;
|
|
break;
|
|
}
|
|
while (i--)
|
|
free(argv[i]);
|
|
LDD_SETENV("TRACE_LOADED_OBJECTS", "yes", 1);
|
|
return (rval);
|
|
}
|
|
#endif
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
char *fmt1, *fmt2;
|
|
const char *rtld;
|
|
int aflag, c, fd, rval, status, is_shlib, rv, type;
|
|
|
|
aflag = 0;
|
|
fmt1 = fmt2 = NULL;
|
|
|
|
while ((c = getopt(argc, argv, "af:")) != -1) {
|
|
switch (c) {
|
|
case 'a':
|
|
aflag++;
|
|
break;
|
|
case 'f':
|
|
if (fmt1 != NULL) {
|
|
if (fmt2 != NULL)
|
|
errx(1, "too many formats");
|
|
fmt2 = optarg;
|
|
} else
|
|
fmt1 = optarg;
|
|
break;
|
|
default:
|
|
usage();
|
|
/* NOTREACHED */
|
|
}
|
|
}
|
|
argc -= optind;
|
|
argv += optind;
|
|
|
|
if (argc <= 0) {
|
|
usage();
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
rval = 0;
|
|
for (; argc > 0; argc--, argv++) {
|
|
if ((fd = open(*argv, O_RDONLY | O_VERIFY, 0)) < 0) {
|
|
warn("%s", *argv);
|
|
rval |= 1;
|
|
continue;
|
|
}
|
|
rv = is_executable(*argv, fd, &is_shlib, &type);
|
|
close(fd);
|
|
if (rv == 0) {
|
|
rval |= 1;
|
|
continue;
|
|
}
|
|
|
|
switch (type) {
|
|
case TYPE_ELF:
|
|
break;
|
|
#if __ELF_WORD_SIZE > 32 && defined(ELF32_SUPPORTED)
|
|
case TYPE_ELF32:
|
|
rval |= execldd32(*argv, fmt1, fmt2, aflag);
|
|
continue;
|
|
#endif
|
|
case TYPE_UNKNOWN:
|
|
default:
|
|
/*
|
|
* This shouldn't happen unless is_executable()
|
|
* is broken.
|
|
*/
|
|
errx(EDOOFUS, "unknown executable type");
|
|
}
|
|
|
|
/* ld.so magic */
|
|
LDD_SETENV("TRACE_LOADED_OBJECTS", "yes", 1);
|
|
if (fmt1 != NULL)
|
|
LDD_SETENV("TRACE_LOADED_OBJECTS_FMT1", fmt1, 1);
|
|
if (fmt2 != NULL)
|
|
LDD_SETENV("TRACE_LOADED_OBJECTS_FMT2", fmt2, 1);
|
|
|
|
LDD_SETENV("TRACE_LOADED_OBJECTS_PROGNAME", *argv, 1);
|
|
if (aflag)
|
|
LDD_SETENV("TRACE_LOADED_OBJECTS_ALL", "1", 1);
|
|
else if (fmt1 == NULL && fmt2 == NULL)
|
|
/* Default formats */
|
|
printf("%s:\n", *argv);
|
|
fflush(stdout);
|
|
|
|
switch (fork()) {
|
|
case -1:
|
|
err(1, "fork");
|
|
break;
|
|
default:
|
|
if (wait(&status) < 0) {
|
|
warn("wait");
|
|
rval |= 1;
|
|
} else if (WIFSIGNALED(status)) {
|
|
fprintf(stderr, "%s: signal %d\n", *argv,
|
|
WTERMSIG(status));
|
|
rval |= 1;
|
|
} else if (WIFEXITED(status) &&
|
|
WEXITSTATUS(status) != 0) {
|
|
fprintf(stderr, "%s: exit status %d\n", *argv,
|
|
WEXITSTATUS(status));
|
|
rval |= 1;
|
|
}
|
|
break;
|
|
case 0:
|
|
rtld = _PATH_RTLD;
|
|
#if __ELF_WORD_SIZE > 32 && defined(ELF32_SUPPORTED)
|
|
if (type == TYPE_ELF32)
|
|
rtld = _COMPAT32_PATH_RTLD;
|
|
#endif
|
|
if (is_shlib == 0) {
|
|
execl(rtld, rtld, "--",
|
|
*argv, (char *)NULL);
|
|
warn("%s", *argv);
|
|
} else if (fmt1 == NULL && fmt2 == NULL && !aflag) {
|
|
dlopen(*argv, RTLD_TRACE);
|
|
warnx("%s: %s", *argv, dlerror());
|
|
} else {
|
|
execl(rtld, rtld, "-d", "--",
|
|
*argv, (char *)NULL);
|
|
}
|
|
_exit(1);
|
|
}
|
|
}
|
|
|
|
return (rval);
|
|
}
|
|
|
|
static void
|
|
usage(void)
|
|
{
|
|
|
|
fprintf(stderr, "usage: ldd [-a] [-f format] program ...\n");
|
|
exit(1);
|
|
}
|
|
|
|
static bool
|
|
has_freebsd_abi_tag(const char *fname, Elf *elf, GElf_Ehdr *ehdr, off_t offset,
|
|
size_t len)
|
|
{
|
|
Elf_Data dst, src;
|
|
const Elf_Note *note;
|
|
char *buf;
|
|
const char *name;
|
|
void *copy;
|
|
size_t namesz, descsz;
|
|
bool has_abi_tag;
|
|
|
|
buf = elf_rawfile(elf, NULL);
|
|
if (buf == NULL) {
|
|
warnx("%s: %s", fname, elf_errmsg(0));
|
|
return (false);
|
|
}
|
|
|
|
memset(&src, 0, sizeof(src));
|
|
src.d_buf = buf + offset;
|
|
src.d_size = len;
|
|
src.d_type = ELF_T_NOTE;
|
|
src.d_version = EV_CURRENT;
|
|
|
|
memset(&dst, 0, sizeof(dst));
|
|
dst.d_buf = copy = malloc(len);
|
|
dst.d_size = len;
|
|
dst.d_type = ELF_T_NOTE;
|
|
dst.d_version = EV_CURRENT;
|
|
|
|
if (gelf_xlatetom(elf, &dst, &src, ehdr->e_ident[EI_DATA]) == NULL) {
|
|
warnx("%s: failed to parse notes: %s", fname, elf_errmsg(0));
|
|
free(copy);
|
|
return (false);
|
|
}
|
|
|
|
buf = copy;
|
|
has_abi_tag = false;
|
|
for (;;) {
|
|
if (len < sizeof(*note))
|
|
break;
|
|
|
|
note = (const void *)buf;
|
|
buf += sizeof(*note);
|
|
len -= sizeof(*note);
|
|
|
|
namesz = roundup2(note->n_namesz, sizeof(uint32_t));
|
|
descsz = roundup2(note->n_descsz, sizeof(uint32_t));
|
|
if (len < namesz + descsz)
|
|
break;
|
|
|
|
name = buf;
|
|
if (note->n_namesz == sizeof(ELF_NOTE_FREEBSD) &&
|
|
strncmp(name, ELF_NOTE_FREEBSD, note->n_namesz) == 0 &&
|
|
note->n_type == NT_FREEBSD_ABI_TAG &&
|
|
note->n_descsz == sizeof(uint32_t)) {
|
|
has_abi_tag = true;
|
|
break;
|
|
}
|
|
|
|
buf += namesz + descsz;
|
|
len -= namesz + descsz;
|
|
}
|
|
|
|
free(copy);
|
|
return (has_abi_tag);
|
|
}
|
|
|
|
static bool
|
|
is_pie(const char *fname, Elf *elf, GElf_Ehdr *ehdr, off_t offset, size_t len)
|
|
{
|
|
Elf_Data dst, src;
|
|
char *buf;
|
|
void *copy;
|
|
const GElf_Dyn *dyn;
|
|
size_t dynsize;
|
|
u_int count, i;
|
|
bool pie;
|
|
|
|
buf = elf_rawfile(elf, NULL);
|
|
if (buf == NULL) {
|
|
warnx("%s: %s", fname, elf_errmsg(0));
|
|
return (false);
|
|
}
|
|
|
|
dynsize = gelf_fsize(elf, ELF_T_DYN, 1, EV_CURRENT);
|
|
if (dynsize == 0) {
|
|
warnx("%s: %s", fname, elf_errmsg(0));
|
|
return (false);
|
|
}
|
|
count = len / dynsize;
|
|
|
|
memset(&src, 0, sizeof(src));
|
|
src.d_buf = buf + offset;
|
|
src.d_size = len;
|
|
src.d_type = ELF_T_DYN;
|
|
src.d_version = EV_CURRENT;
|
|
|
|
memset(&dst, 0, sizeof(dst));
|
|
dst.d_buf = copy = malloc(count * sizeof(*dyn));
|
|
dst.d_size = count * sizeof(*dyn);
|
|
dst.d_type = ELF_T_DYN;
|
|
dst.d_version = EV_CURRENT;
|
|
|
|
if (gelf_xlatetom(elf, &dst, &src, ehdr->e_ident[EI_DATA]) == NULL) {
|
|
warnx("%s: failed to parse .dynamic: %s", fname, elf_errmsg(0));
|
|
free(copy);
|
|
return (false);
|
|
}
|
|
|
|
dyn = copy;
|
|
pie = false;
|
|
for (i = 0; i < count; i++) {
|
|
if (dyn[i].d_tag != DT_FLAGS_1)
|
|
continue;
|
|
|
|
pie = (dyn[i].d_un.d_val & DF_1_PIE) != 0;
|
|
break;
|
|
}
|
|
|
|
free(copy);
|
|
return (pie);
|
|
}
|
|
|
|
static int
|
|
is_executable(const char *fname, int fd, int *is_shlib, int *type)
|
|
{
|
|
Elf *elf;
|
|
GElf_Ehdr ehdr;
|
|
GElf_Phdr phdr;
|
|
bool dynamic, freebsd, pie;
|
|
int i;
|
|
|
|
*is_shlib = 0;
|
|
*type = TYPE_UNKNOWN;
|
|
dynamic = false;
|
|
freebsd = false;
|
|
pie = false;
|
|
|
|
if (elf_version(EV_CURRENT) == EV_NONE) {
|
|
warnx("unsupported libelf");
|
|
return (0);
|
|
}
|
|
elf = elf_begin(fd, ELF_C_READ, NULL);
|
|
if (elf == NULL) {
|
|
warnx("%s: %s", fname, elf_errmsg(0));
|
|
return (0);
|
|
}
|
|
if (elf_kind(elf) != ELF_K_ELF) {
|
|
elf_end(elf);
|
|
warnx("%s: not a dynamic ELF executable", fname);
|
|
return (0);
|
|
}
|
|
if (gelf_getehdr(elf, &ehdr) == NULL) {
|
|
warnx("%s: %s", fname, elf_errmsg(0));
|
|
elf_end(elf);
|
|
return (0);
|
|
}
|
|
|
|
*type = TYPE_ELF;
|
|
#if __ELF_WORD_SIZE > 32 && defined(ELF32_SUPPORTED)
|
|
if (gelf_getclass(elf) == ELFCLASS32) {
|
|
*type = TYPE_ELF32;
|
|
}
|
|
#endif
|
|
|
|
freebsd = ehdr.e_ident[EI_OSABI] == ELFOSABI_FREEBSD;
|
|
for (i = 0; i < ehdr.e_phnum; i++) {
|
|
if (gelf_getphdr(elf, i, &phdr) == NULL) {
|
|
warnx("%s: %s", fname, elf_errmsg(0));
|
|
elf_end(elf);
|
|
return (0);
|
|
}
|
|
switch (phdr.p_type) {
|
|
case PT_NOTE:
|
|
if (ehdr.e_ident[EI_OSABI] == ELFOSABI_NONE && !freebsd)
|
|
freebsd = has_freebsd_abi_tag(fname, elf, &ehdr,
|
|
phdr.p_offset, phdr.p_filesz);
|
|
break;
|
|
case PT_DYNAMIC:
|
|
dynamic = true;
|
|
if (ehdr.e_type == ET_DYN)
|
|
pie = is_pie(fname, elf, &ehdr, phdr.p_offset,
|
|
phdr.p_filesz);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!dynamic) {
|
|
elf_end(elf);
|
|
warnx("%s: not a dynamic ELF executable", fname);
|
|
return (0);
|
|
}
|
|
|
|
if (ehdr.e_type == ET_DYN && !pie) {
|
|
*is_shlib = 1;
|
|
|
|
if (!freebsd) {
|
|
elf_end(elf);
|
|
warnx("%s: not a FreeBSD ELF shared object", fname);
|
|
return (0);
|
|
}
|
|
}
|
|
|
|
elf_end(elf);
|
|
return (1);
|
|
}
|