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Index: head/tools/tools/controlelf/Makefile
===================================================================
--- head/tools/tools/controlelf/Makefile
+++ head/tools/tools/controlelf/Makefile
@@ -1,14 +0,0 @@
-# $FreeBSD$
-
-ELFTCDIR= ${SRCTOP}/contrib/elftoolchain
-
-PROG= controlelf
-SRCS= controlelf.c
-
-LIBADD= elftc elf
-
-CFLAGS+=-I${ELFTCDIR}/libelftc -I${ELFTCDIR}/common
-
-WARNS?= 6
-
-.include <bsd.prog.mk>
Index: head/tools/tools/controlelf/controlelf.1
===================================================================
--- head/tools/tools/controlelf/controlelf.1
+++ head/tools/tools/controlelf/controlelf.1
@@ -1,94 +0,0 @@
-.\" Copyright 2019 The FreeBSD Foundation.
-.\"
-.\" This software was developed by Bora Ozarslan under sponsorship from
-.\" the FreeBSD Foundation.
-.\"
-.\" 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.
-.\"
-.\" $FreeBSD$
-.\"
-.Dd September 27, 2019
-.Dt CONTROLELF 1
-.Os
-.Sh NAME
-.Nm controlelf
-.Nd change an ELF binary's feature control note
-.Sh SYNOPSIS
-.Nm
-.Op Fl h | Fl -help
-.Op Fl l
-.Op Fl e Ar featurelist
-.Ar
-.Sh DESCRIPTION
-The
-.Nm
-utility modifies feature flags in the feature control note in an ELF binary.
-.Pp
-The options are as follows:
-.Bl -tag -width indent
-.It Fl h | Fl -help
-Print a usage message and exit.
-.It Fl l
-List known ELF feature flags.
-.It Fl e Ar featurelist
-Edit features from the given comma separated list
-.Ar featurelist .
-.Ar featurelist
-starts with one of the three operations:
-.Dq Li +
-to turn on the features,
-.Dq Li -
-to turn off the features,
-.Dq Li =
-to only turn on the given features.
-A comma separated list of feature names follows the operation.
-.El
-.Pp
-If
-.Fl e
-is not specified
-.Nm
-displays the status of each feature in the ELF note in each
-.Ar .
-.Sh EXIT STATUS
-Exit status is 0 on success, and 1 if the command
-fails if a file does not exist, is too short,
-or fails to find or edit features note.
-.Sh EXAMPLES
-The following is an example of a typical usage
-of the
-.Nm
-command:
-.Bd -literal -offset indent
-controlelf file
-controlelf -e +aslr file
-.Ed
-.Sh HISTORY
-.Nm
-first appeared in
-.Fx 13.0 .
-.Sh AUTHORS
-.Nm
-was written by
-.An Bora Ozarslan Mt borako.ozarslan@gmail.com
-under sponsorship from the
-.Fx Foundation.
Index: head/tools/tools/controlelf/controlelf.c
===================================================================
--- head/tools/tools/controlelf/controlelf.c
+++ head/tools/tools/controlelf/controlelf.c
@@ -1,392 +0,0 @@
-/*-
- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
- *
- * Copyright (c) 2019 The FreeBSD Foundation.
- *
- * This software was developed by Bora Ozarslan under sponsorship from
- * the FreeBSD Foundation.
- *
- * 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/elf_common.h>
-#include <sys/endian.h>
-#include <sys/stat.h>
-
-#include <err.h>
-#include <fcntl.h>
-#include <gelf.h>
-#include <getopt.h>
-#include <libelf.h>
-#include <stdbool.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include "_elftc.h"
-
-__FBSDID("$FreeBSD$");
-
-static bool convert_to_feature_val(char *, u_int32_t *);
-static bool edit_file_features(Elf *, int, int, char *);
-static bool get_file_features(Elf *, int, int, u_int32_t *, u_int64_t *);
-static void print_features(void);
-static bool print_file_features(Elf *, int, int, char *);
-static void usage(void);
-
-struct ControlFeatures {
- const char *alias;
- unsigned long value;
- const char *desc;
-};
-
-static struct ControlFeatures featurelist[] = {
- { "aslr", NT_FREEBSD_FCTL_ASLR_DISABLE, "Disable ASLR" },
- { "protmax", NT_FREEBSD_FCTL_PROTMAX_DISABLE,
- "Disable implicit PROT_MAX" },
- { "stackgap", NT_FREEBSD_FCTL_STKGAP_DISABLE, "Disable stack gap" },
-};
-
-static struct option long_opts[] = {
- { "help", no_argument, NULL, 'h' },
- { NULL, 0, NULL, 0 }
-};
-
-#if BYTE_ORDER == LITTLE_ENDIAN
-#define SUPPORTED_ENDIAN ELFDATA2LSB
-#else
-#define SUPPORTED_ENDIAN ELFDATA2MSB
-#endif
-
-int
-main(int argc, char **argv)
-{
- GElf_Ehdr ehdr;
- Elf *elf;
- Elf_Kind kind;
- int ch, fd, editfeatures, retval;
- char *features;
- bool lflag;
-
- lflag = 0;
- editfeatures = 0;
- retval = 0;
-
- if (elf_version(EV_CURRENT) == EV_NONE)
- errx(EXIT_FAILURE, "elf_version error");
-
- while ((ch = getopt_long(argc, argv, "hle:", long_opts, NULL)) != -1) {
- switch (ch) {
- case 'l':
- print_features();
- lflag = true;
- break;
- case 'e':
- features = optarg;
- editfeatures = 1;
- break;
- case 'h':
- default:
- usage();
- }
- }
- argc -= optind;
- argv += optind;
- if (argc == 0) {
- if (lflag)
- exit(0);
- else {
- warnx("no file(s) specified");
- usage();
- }
- }
-
- while (argc) {
- elf = NULL;
-
- if ((fd = open(argv[0],
- editfeatures ? O_RDWR : O_RDONLY, 0)) < 0) {
- warn("error opening file %s", argv[0]);
- retval = 1;
- goto fail;
- }
-
- if ((elf = elf_begin(fd, ELF_C_READ, NULL)) == NULL) {
- warnx("elf_begin failed: %s", elf_errmsg(-1));
- retval = 1;
- goto fail;
- }
-
- if ((kind = elf_kind(elf)) != ELF_K_ELF) {
- if (kind == ELF_K_AR)
- warnx("file '%s' is an archive", argv[0]);
- else
- warnx("file '%s' is not an ELF file", argv[0]);
- retval = 1;
- goto fail;
- }
-
- if (gelf_getehdr(elf, &ehdr) == NULL) {
- warnx("gelf_getehdr: %s", elf_errmsg(-1));
- retval = 1;
- goto fail;
- }
- /*
- * XXX need to support cross-endian operation, but for now
- * exit on error rather than misbehaving.
- */
- if (ehdr.e_ident[EI_DATA] != SUPPORTED_ENDIAN) {
- warnx("file endianness must match host");
- retval = 1;
- goto fail;
- }
-
- if (!editfeatures) {
- if (!print_file_features(elf, ehdr.e_phnum, fd,
- argv[0])) {
- retval = 1;
- goto fail;
- }
- } else if (!edit_file_features(elf, ehdr.e_phnum, fd,
- features)) {
- retval = 1;
- goto fail;
- }
-fail:
- if (elf != NULL)
- elf_end(elf);
-
- if (fd >= 0)
- close(fd);
-
- argc--;
- argv++;
- }
-
- return (retval);
-}
-
-#define USAGE_MESSAGE \
- "\
-Usage: %s [options] file...\n\
- Set or display the control features for an ELF object.\n\n\
- Supported options are:\n\
- -l List known control features.\n\
- -e [+-=]feature,list Edit features from a comma separated list.\n\
- -h | --help Print a usage message and exit.\n"
-
-static void
-usage(void)
-{
-
- fprintf(stderr, USAGE_MESSAGE, ELFTC_GETPROGNAME());
- exit(1);
-}
-
-static bool
-convert_to_feature_val(char *feature_str, u_int32_t *feature_val)
-{
- char *feature;
- int i, len;
- u_int32_t input;
- char operation;
-
- input = 0;
- operation = *feature_str;
- feature_str++;
- len = nitems(featurelist);
- while ((feature = strsep(&feature_str, ",")) != NULL) {
- for (i = 0; i < len; ++i) {
- if (strcmp(featurelist[i].alias, feature) == 0) {
- input |= featurelist[i].value;
- break;
- }
- }
- if (i == len) {
- warnx("%s is not a valid feature", feature);
- return (false);
- }
- }
-
- if (operation == '+') {
- *feature_val |= input;
- } else if (operation == '=') {
- *feature_val = input;
- } else if (operation == '-') {
- *feature_val &= ~input;
- } else {
- warnx("'%c' not an operator - use '+', '-', '='",
- feature_str[0]);
- return (false);
- }
- return (true);
-}
-
-static bool
-edit_file_features(Elf *elf, int phcount, int fd, char *val)
-{
- u_int32_t features;
- u_int64_t off;
-
- if (!get_file_features(elf, phcount, fd, &features, &off)) {
- warnx("NT_FREEBSD_FEATURE_CTL note not found");
- return (false);
- }
-
- if (!convert_to_feature_val(val, &features))
- return (false);
-
- if (lseek(fd, off, SEEK_SET) == -1 ||
- write(fd, &features, sizeof(features)) <
- (ssize_t)sizeof(features)) {
- warnx("error writing feature value");
- return (false);
- }
- return (true);
-}
-
-static void
-print_features(void)
-{
- size_t i;
-
- printf("Known features are:\n");
- for (i = 0; i < nitems(featurelist); ++i)
- printf("%-16s%s\n", featurelist[i].alias,
- featurelist[i].desc);
-}
-
-static bool
-print_file_features(Elf *elf, int phcount, int fd, char *filename)
-{
- u_int32_t features;
- unsigned long i;
-
- if (!get_file_features(elf, phcount, fd, &features, NULL)) {
- return (false);
- }
-
- printf("File '%s' features:\n", filename);
- for (i = 0; i < nitems(featurelist); ++i) {
- printf("%-16s'%s' is ", featurelist[i].alias,
- featurelist[i].desc);
-
- if ((featurelist[i].value & features) == 0)
- printf("un");
-
- printf("set.\n");
- }
- return (true);
-}
-
-static bool
-get_file_features(Elf *elf, int phcount, int fd, u_int32_t *features,
- u_int64_t *off)
-{
- GElf_Phdr phdr;
- Elf_Note note;
- unsigned long read_total;
- int namesz, descsz, i;
- char *name;
- ssize_t size;
-
- /*
- * Go through each program header to find one that is of type PT_NOTE
- * and has a note for feature control.
- */
- for (i = 0; i < phcount; ++i) {
- if (gelf_getphdr(elf, i, &phdr) == NULL) {
- warnx("gelf_getphdr failed: %s", elf_errmsg(-1));
- return (false);
- }
-
- if (phdr.p_type != PT_NOTE)
- continue;
-
- if (lseek(fd, phdr.p_offset, SEEK_SET) < 0) {
- warn("lseek() failed:");
- return (false);
- }
-
- read_total = 0;
- while (read_total < phdr.p_filesz) {
- size = read(fd, &note, sizeof(note));
- if (size < (ssize_t)sizeof(note)) {
- warn("read() failed:");
- return (false);
- }
- read_total += sizeof(note);
-
- /*
- * XXX: Name and descriptor are 4 byte aligned, however,
- * the size given doesn't include the padding.
- */
- namesz = roundup2(note.n_namesz, 4);
- name = malloc(namesz);
- if (name == NULL) {
- warn("malloc() failed.");
- return (false);
- }
- descsz = roundup2(note.n_descsz, 4);
- size = read(fd, name, namesz);
- read_total += namesz;
-
- if (note.n_namesz != 8 ||
- strncmp("FreeBSD", name, 7) != 0 ||
- note.n_type != NT_FREEBSD_FEATURE_CTL) {
- /* Not the right note. Skip the description */
- if (lseek(fd, descsz, SEEK_CUR) < 0) {
- warn("lseek() failed.");
- free(name);
- return (false);
- }
- read_total += descsz;
- free(name);
- continue;
- }
-
- if (note.n_descsz < sizeof(u_int32_t)) {
- warnx("Feature descriptor can't "
- "be less than 4 bytes");
- free(name);
- return (false);
- }
-
- /*
- * XXX: For now we look at only 4 bytes of the
- * descriptor. This should respect descsz.
- */
- if (note.n_descsz > sizeof(u_int32_t))
- warnx("Feature note is bigger than expected");
- read(fd, features, sizeof(u_int32_t));
- if (off != NULL)
- *off = phdr.p_offset + read_total;
- free(name);
- return (true);
- }
- }
-
- warnx("NT_FREEBSD_FEATURE_CTL note not found");
- return (false);
-}
Index: head/usr.bin/Makefile
===================================================================
--- head/usr.bin/Makefile
+++ head/usr.bin/Makefile
@@ -31,6 +31,7 @@
diff \
dirname \
du \
+ elfctl \
elfdump \
enigma \
env \
Index: head/usr.bin/elfctl/Makefile
===================================================================
--- head/usr.bin/elfctl/Makefile
+++ head/usr.bin/elfctl/Makefile
@@ -0,0 +1,11 @@
+# $FreeBSD$
+
+ELFTCDIR= ${SRCTOP}/contrib/elftoolchain
+
+PROG= elfctl
+
+LIBADD= elftc elf
+
+CFLAGS+=-I${ELFTCDIR}/libelftc -I${ELFTCDIR}/common
+
+.include <bsd.prog.mk>
Index: head/usr.bin/elfctl/elfctl.1
===================================================================
--- head/usr.bin/elfctl/elfctl.1
+++ head/usr.bin/elfctl/elfctl.1
@@ -0,0 +1,94 @@
+.\" Copyright 2019 The FreeBSD Foundation.
+.\"
+.\" This software was developed by Bora Ozarslan under sponsorship from
+.\" the FreeBSD Foundation.
+.\"
+.\" 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd March 1, 2020
+.Dt ELFCTL 1
+.Os
+.Sh NAME
+.Nm elfctl
+.Nd change an ELF binary's feature control note
+.Sh SYNOPSIS
+.Nm
+.Op Fl h | Fl -help
+.Op Fl l
+.Op Fl e Ar featurelist
+.Ar
+.Sh DESCRIPTION
+The
+.Nm
+utility modifies feature flags in the feature control note in an ELF binary.
+.Pp
+The options are as follows:
+.Bl -tag -width indent
+.It Fl h | Fl -help
+Print a usage message and exit.
+.It Fl l
+List known ELF feature flags.
+.It Fl e Ar featurelist
+Edit features from the given comma separated list
+.Ar featurelist .
+.Ar featurelist
+starts with one of the three operations:
+.Dq Li +
+to turn on the features,
+.Dq Li -
+to turn off the features,
+.Dq Li =
+to only turn on the given features.
+A comma separated list of feature names follows the operation.
+.El
+.Pp
+If
+.Fl e
+is not specified
+.Nm
+displays the status of each feature in the ELF note in each
+.Ar .
+.Sh EXIT STATUS
+Exit status is 0 on success, and 1 if the command
+fails if a file does not exist, is too short,
+or fails to find or edit features note.
+.Sh EXAMPLES
+The following is an example of a typical usage
+of the
+.Nm
+command:
+.Bd -literal -offset indent
+elfctl file
+elfctl -e +aslr file
+.Ed
+.Sh HISTORY
+.Nm
+first appeared in
+.Fx 13.0 .
+.Sh AUTHORS
+.Nm
+was written by
+.An Bora Ozarslan Mt borako.ozarslan@gmail.com
+under sponsorship from the
+.Fx Foundation.
Index: head/usr.bin/elfctl/elfctl.c
===================================================================
--- head/usr.bin/elfctl/elfctl.c
+++ head/usr.bin/elfctl/elfctl.c
@@ -0,0 +1,392 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2019 The FreeBSD Foundation.
+ *
+ * This software was developed by Bora Ozarslan under sponsorship from
+ * the FreeBSD Foundation.
+ *
+ * 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/elf_common.h>
+#include <sys/endian.h>
+#include <sys/stat.h>
+
+#include <err.h>
+#include <fcntl.h>
+#include <gelf.h>
+#include <getopt.h>
+#include <libelf.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "_elftc.h"
+
+__FBSDID("$FreeBSD$");
+
+static bool convert_to_feature_val(char *, u_int32_t *);
+static bool edit_file_features(Elf *, int, int, char *);
+static bool get_file_features(Elf *, int, int, u_int32_t *, u_int64_t *);
+static void print_features(void);
+static bool print_file_features(Elf *, int, int, char *);
+static void usage(void);
+
+struct ControlFeatures {
+ const char *alias;
+ unsigned long value;
+ const char *desc;
+};
+
+static struct ControlFeatures featurelist[] = {
+ { "aslr", NT_FREEBSD_FCTL_ASLR_DISABLE, "Disable ASLR" },
+ { "protmax", NT_FREEBSD_FCTL_PROTMAX_DISABLE,
+ "Disable implicit PROT_MAX" },
+ { "stackgap", NT_FREEBSD_FCTL_STKGAP_DISABLE, "Disable stack gap" },
+};
+
+static struct option long_opts[] = {
+ { "help", no_argument, NULL, 'h' },
+ { NULL, 0, NULL, 0 }
+};
+
+#if BYTE_ORDER == LITTLE_ENDIAN
+#define SUPPORTED_ENDIAN ELFDATA2LSB
+#else
+#define SUPPORTED_ENDIAN ELFDATA2MSB
+#endif
+
+int
+main(int argc, char **argv)
+{
+ GElf_Ehdr ehdr;
+ Elf *elf;
+ Elf_Kind kind;
+ int ch, fd, editfeatures, retval;
+ char *features;
+ bool lflag;
+
+ lflag = 0;
+ editfeatures = 0;
+ retval = 0;
+
+ if (elf_version(EV_CURRENT) == EV_NONE)
+ errx(EXIT_FAILURE, "elf_version error");
+
+ while ((ch = getopt_long(argc, argv, "hle:", long_opts, NULL)) != -1) {
+ switch (ch) {
+ case 'l':
+ print_features();
+ lflag = true;
+ break;
+ case 'e':
+ features = optarg;
+ editfeatures = 1;
+ break;
+ case 'h':
+ default:
+ usage();
+ }
+ }
+ argc -= optind;
+ argv += optind;
+ if (argc == 0) {
+ if (lflag)
+ exit(0);
+ else {
+ warnx("no file(s) specified");
+ usage();
+ }
+ }
+
+ while (argc) {
+ elf = NULL;
+
+ if ((fd = open(argv[0],
+ editfeatures ? O_RDWR : O_RDONLY, 0)) < 0) {
+ warn("error opening file %s", argv[0]);
+ retval = 1;
+ goto fail;
+ }
+
+ if ((elf = elf_begin(fd, ELF_C_READ, NULL)) == NULL) {
+ warnx("elf_begin failed: %s", elf_errmsg(-1));
+ retval = 1;
+ goto fail;
+ }
+
+ if ((kind = elf_kind(elf)) != ELF_K_ELF) {
+ if (kind == ELF_K_AR)
+ warnx("file '%s' is an archive", argv[0]);
+ else
+ warnx("file '%s' is not an ELF file", argv[0]);
+ retval = 1;
+ goto fail;
+ }
+
+ if (gelf_getehdr(elf, &ehdr) == NULL) {
+ warnx("gelf_getehdr: %s", elf_errmsg(-1));
+ retval = 1;
+ goto fail;
+ }
+ /*
+ * XXX need to support cross-endian operation, but for now
+ * exit on error rather than misbehaving.
+ */
+ if (ehdr.e_ident[EI_DATA] != SUPPORTED_ENDIAN) {
+ warnx("file endianness must match host");
+ retval = 1;
+ goto fail;
+ }
+
+ if (!editfeatures) {
+ if (!print_file_features(elf, ehdr.e_phnum, fd,
+ argv[0])) {
+ retval = 1;
+ goto fail;
+ }
+ } else if (!edit_file_features(elf, ehdr.e_phnum, fd,
+ features)) {
+ retval = 1;
+ goto fail;
+ }
+fail:
+ if (elf != NULL)
+ elf_end(elf);
+
+ if (fd >= 0)
+ close(fd);
+
+ argc--;
+ argv++;
+ }
+
+ return (retval);
+}
+
+#define USAGE_MESSAGE \
+ "\
+Usage: %s [options] file...\n\
+ Set or display the control features for an ELF object.\n\n\
+ Supported options are:\n\
+ -l List known control features.\n\
+ -e [+-=]feature,list Edit features from a comma separated list.\n\
+ -h | --help Print a usage message and exit.\n"
+
+static void
+usage(void)
+{
+
+ fprintf(stderr, USAGE_MESSAGE, ELFTC_GETPROGNAME());
+ exit(1);
+}
+
+static bool
+convert_to_feature_val(char *feature_str, u_int32_t *feature_val)
+{
+ char *feature;
+ int i, len;
+ u_int32_t input;
+ char operation;
+
+ input = 0;
+ operation = *feature_str;
+ feature_str++;
+ len = nitems(featurelist);
+ while ((feature = strsep(&feature_str, ",")) != NULL) {
+ for (i = 0; i < len; ++i) {
+ if (strcmp(featurelist[i].alias, feature) == 0) {
+ input |= featurelist[i].value;
+ break;
+ }
+ }
+ if (i == len) {
+ warnx("%s is not a valid feature", feature);
+ return (false);
+ }
+ }
+
+ if (operation == '+') {
+ *feature_val |= input;
+ } else if (operation == '=') {
+ *feature_val = input;
+ } else if (operation == '-') {
+ *feature_val &= ~input;
+ } else {
+ warnx("'%c' not an operator - use '+', '-', '='",
+ feature_str[0]);
+ return (false);
+ }
+ return (true);
+}
+
+static bool
+edit_file_features(Elf *elf, int phcount, int fd, char *val)
+{
+ u_int32_t features;
+ u_int64_t off;
+
+ if (!get_file_features(elf, phcount, fd, &features, &off)) {
+ warnx("NT_FREEBSD_FEATURE_CTL note not found");
+ return (false);
+ }
+
+ if (!convert_to_feature_val(val, &features))
+ return (false);
+
+ if (lseek(fd, off, SEEK_SET) == -1 ||
+ write(fd, &features, sizeof(features)) <
+ (ssize_t)sizeof(features)) {
+ warnx("error writing feature value");
+ return (false);
+ }
+ return (true);
+}
+
+static void
+print_features(void)
+{
+ size_t i;
+
+ printf("Known features are:\n");
+ for (i = 0; i < nitems(featurelist); ++i)
+ printf("%-16s%s\n", featurelist[i].alias,
+ featurelist[i].desc);
+}
+
+static bool
+print_file_features(Elf *elf, int phcount, int fd, char *filename)
+{
+ u_int32_t features;
+ unsigned long i;
+
+ if (!get_file_features(elf, phcount, fd, &features, NULL)) {
+ return (false);
+ }
+
+ printf("File '%s' features:\n", filename);
+ for (i = 0; i < nitems(featurelist); ++i) {
+ printf("%-16s'%s' is ", featurelist[i].alias,
+ featurelist[i].desc);
+
+ if ((featurelist[i].value & features) == 0)
+ printf("un");
+
+ printf("set.\n");
+ }
+ return (true);
+}
+
+static bool
+get_file_features(Elf *elf, int phcount, int fd, u_int32_t *features,
+ u_int64_t *off)
+{
+ GElf_Phdr phdr;
+ Elf_Note note;
+ unsigned long read_total;
+ int namesz, descsz, i;
+ char *name;
+ ssize_t size;
+
+ /*
+ * Go through each program header to find one that is of type PT_NOTE
+ * and has a note for feature control.
+ */
+ for (i = 0; i < phcount; ++i) {
+ if (gelf_getphdr(elf, i, &phdr) == NULL) {
+ warnx("gelf_getphdr failed: %s", elf_errmsg(-1));
+ return (false);
+ }
+
+ if (phdr.p_type != PT_NOTE)
+ continue;
+
+ if (lseek(fd, phdr.p_offset, SEEK_SET) < 0) {
+ warn("lseek() failed:");
+ return (false);
+ }
+
+ read_total = 0;
+ while (read_total < phdr.p_filesz) {
+ size = read(fd, &note, sizeof(note));
+ if (size < (ssize_t)sizeof(note)) {
+ warn("read() failed:");
+ return (false);
+ }
+ read_total += sizeof(note);
+
+ /*
+ * XXX: Name and descriptor are 4 byte aligned, however,
+ * the size given doesn't include the padding.
+ */
+ namesz = roundup2(note.n_namesz, 4);
+ name = malloc(namesz);
+ if (name == NULL) {
+ warn("malloc() failed.");
+ return (false);
+ }
+ descsz = roundup2(note.n_descsz, 4);
+ size = read(fd, name, namesz);
+ read_total += namesz;
+
+ if (note.n_namesz != 8 ||
+ strncmp("FreeBSD", name, 7) != 0 ||
+ note.n_type != NT_FREEBSD_FEATURE_CTL) {
+ /* Not the right note. Skip the description */
+ if (lseek(fd, descsz, SEEK_CUR) < 0) {
+ warn("lseek() failed.");
+ free(name);
+ return (false);
+ }
+ read_total += descsz;
+ free(name);
+ continue;
+ }
+
+ if (note.n_descsz < sizeof(u_int32_t)) {
+ warnx("Feature descriptor can't "
+ "be less than 4 bytes");
+ free(name);
+ return (false);
+ }
+
+ /*
+ * XXX: For now we look at only 4 bytes of the
+ * descriptor. This should respect descsz.
+ */
+ if (note.n_descsz > sizeof(u_int32_t))
+ warnx("Feature note is bigger than expected");
+ read(fd, features, sizeof(u_int32_t));
+ if (off != NULL)
+ *off = phdr.p_offset + read_total;
+ free(name);
+ return (true);
+ }
+ }
+
+ warnx("NT_FREEBSD_FEATURE_CTL note not found");
+ return (false);
+}

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