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Diffstat (limited to 'usr.bin/ldd/ldd.c')
-rw-r--r--usr.bin/ldd/ldd.c471
1 files changed, 471 insertions, 0 deletions
diff --git a/usr.bin/ldd/ldd.c b/usr.bin/ldd/ldd.c
new file mode 100644
index 000000000000..1c0fc0fbc2ea
--- /dev/null
+++ b/usr.bin/ldd/ldd.c
@@ -0,0 +1,471 @@
+/*-
+ * 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/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 = __PATH_RTLD("32");
+#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 [-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);
+}
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