util-linux/setpriv.c - busybox - Git at Google

 /* vi: set sw=4 ts=4: */
 /*
  * setpriv implementation for busybox based on linux-utils-ng 2.29
  *
  * Copyright (C) 2017 by  <assafgordon@gmail.com>
  *
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 //config:config SETPRIV
 //config:	bool "setpriv (6.6 kb)"
 //config:	default y
 //config:	select PLATFORM_LINUX
 //config:	select LONG_OPTS
 //config:	help
 //config:	Run a program with different Linux privilege settings.
 //config:	Requires kernel >= 3.5
 //config:
 //config:config FEATURE_SETPRIV_DUMP
 //config:	bool "Support dumping current privilege state"
 //config:	default y
 //config:	depends on SETPRIV
 //config:	help
 //config:	Enables the "--dump" switch to print out the current privilege
 //config:	state. This is helpful for diagnosing problems.
 //config:
 //config:config FEATURE_SETPRIV_CAPABILITIES
 //config:	bool "Support capabilities"
 //config:	default y
 //config:	depends on SETPRIV
 //config:	help
 //config:	Capabilities can be used to grant processes additional rights
 //config:	without the necessity to always execute as the root user.
 //config:	Enabling this option enables "--dump" to show information on
 //config:	capabilities.
 //config:
 //config:config FEATURE_SETPRIV_CAPABILITY_NAMES
 //config:	bool "Support capability names"
 //config:	default y
 //config:	depends on SETPRIV && FEATURE_SETPRIV_CAPABILITIES
 //config:	help
 //config:	Capabilities can be either referenced via a human-readble name,
 //config:	e.g. "net_admin", or using their index, e.g. "cap_12". Enabling
 //config:	this option allows using the human-readable names in addition to
 //config:	the index-based names.

 //applet:IF_SETPRIV(APPLET(setpriv, BB_DIR_BIN, BB_SUID_DROP))

 //kbuild:lib-$(CONFIG_SETPRIV) += setpriv.o

 //usage:#define setpriv_trivial_usage
 //usage:	"[OPTIONS] PROG [ARGS]"
 //usage:#define setpriv_full_usage "\n\n"
 //usage:       "Run PROG with different privilege settings\n"
 //usage:	IF_FEATURE_SETPRIV_DUMP(
 //usage:     "\n-d,--dump		Show current capabilities"
 //usage:	)
 //usage:     "\n--nnp,--no-new-privs	Ignore setuid/setgid bits and file capabilities"
 //usage:	IF_FEATURE_SETPRIV_CAPABILITIES(
 //usage:     "\n--inh-caps CAP,CAP	Set inheritable capabilities"
 //usage:     "\n--ambient-caps CAP,CAP	Set ambient capabilities"
 //usage:	)

 //setpriv from util-linux 2.28:
 // -d, --dump               show current state (and do not exec anything)
 // --nnp, --no-new-privs    disallow granting new privileges
 // --inh-caps <caps,...>    set inheritable capabilities
 // --bounding-set <caps>    set capability bounding set
 // --ruid <uid>             set real uid
 // --euid <uid>             set effective uid
 // --rgid <gid>             set real gid
 // --egid <gid>             set effective gid
 // --reuid <uid>            set real and effective uid
 // --regid <gid>            set real and effective gid
 // --clear-groups           clear supplementary groups
 // --keep-groups            keep supplementary groups
 // --groups <group,...>     set supplementary groups
 // --securebits <bits>      set securebits
 // --selinux-label <label>  set SELinux label
 // --apparmor-profile <pr>  set AppArmor profile

 #if ENABLE_FEATURE_SETPRIV_CAPABILITIES
 #include <linux/capability.h>
 // #include <sys/capability.h>
 // This header is in libcap, but the functions are in libc.
 // Comment in the header says this above capset/capget:
 /* system calls - look to libc for function to system call mapping */
 extern int capset(cap_user_header_t header, cap_user_data_t data);
 extern int capget(cap_user_header_t header, const cap_user_data_t data);
 // so for bbox, let's just repeat the declarations.
 // This way, libcap needs not be installed in build environment.
 #endif
 #include <sys/prctl.h>
 #include "libbb.h"

 #ifndef PR_CAPBSET_READ
 #define PR_CAPBSET_READ 23
 #endif

 #ifndef PR_SET_NO_NEW_PRIVS
 #define PR_SET_NO_NEW_PRIVS 38
 #endif

 #ifndef PR_GET_NO_NEW_PRIVS
 #define PR_GET_NO_NEW_PRIVS 39
 #endif

 #ifndef PR_CAP_AMBIENT
 #define PR_CAP_AMBIENT 47
 #define PR_CAP_AMBIENT_IS_SET 1
 #define PR_CAP_AMBIENT_RAISE 2
 #define PR_CAP_AMBIENT_LOWER 3
 #endif

 enum {
 	IF_FEATURE_SETPRIV_DUMP(OPTBIT_DUMP,)
 	IF_FEATURE_SETPRIV_CAPABILITIES(OPTBIT_INH,)
 	IF_FEATURE_SETPRIV_CAPABILITIES(OPTBIT_AMB,)
 	OPTBIT_NNP,

 	IF_FEATURE_SETPRIV_DUMP(OPT_DUMP = (1 << OPTBIT_DUMP),)
 	IF_FEATURE_SETPRIV_CAPABILITIES(OPT_INH  = (1 << OPTBIT_INH),)
 	IF_FEATURE_SETPRIV_CAPABILITIES(OPT_AMB  = (1 << OPTBIT_AMB),)
 	OPT_NNP  = (1 << OPTBIT_NNP),
 };

 #if ENABLE_FEATURE_SETPRIV_CAPABILITIES
 DEFINE_STRUCT_CAPS;

 static unsigned parse_cap(const char *cap)
 {
 	switch (cap[0]) {
 	case '-':
 		break;
 	case '+':
 		break;
 	default:
 		bb_error_msg_and_die("invalid capability '%s'", cap);
 		break;
 	}

 	cap++;
 	return cap_name_to_number(cap);
 }

 static void set_inh_caps(char *capstring)
 {
 	struct caps caps;

 	getcaps(&caps);

 	capstring = strtok(capstring, ",");
 	while (capstring) {
 		unsigned cap;

 		cap = parse_cap(capstring);
 		if (CAP_TO_INDEX(cap) >= caps.u32s)
 			bb_error_msg_and_die("invalid capability '%s'", capstring);

 		if (capstring[0] == '+')
 			caps.data[CAP_TO_INDEX(cap)].inheritable |= CAP_TO_MASK(cap);
 		else
 			caps.data[CAP_TO_INDEX(cap)].inheritable &= ~CAP_TO_MASK(cap);
 		capstring = strtok(NULL, ",");
 	}

 	if (capset(&caps.header, caps.data) != 0)
 		bb_simple_perror_msg_and_die("capset");
 }

 static void set_ambient_caps(char *string)
 {
 	char *cap;

 	cap = strtok(string, ",");
 	while (cap) {
 		unsigned idx;

 		idx = parse_cap(cap);
 		if (cap[0] == '+') {
 			if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, idx, 0, 0) < 0)
 				bb_simple_perror_msg("cap_ambient_raise");
 		} else {
 			if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_LOWER, idx, 0, 0) < 0)
 				bb_simple_perror_msg("cap_ambient_lower");
 		}
 		cap = strtok(NULL, ",");
 	}
 }
 #endif /* FEATURE_SETPRIV_CAPABILITIES */

 #if ENABLE_FEATURE_SETPRIV_DUMP
 # if !ENABLE_FEATURE_SETPRIV_CAPABILITY_NAMES
 #  define printf_cap(pfx, cap_no) printf("%scap_%u", (pfx), (cap_no))
 # endif

 static int dump(void)
 {
 	IF_FEATURE_SETPRIV_CAPABILITIES(struct caps caps;)
 	const char *fmt;
 	uid_t ruid, euid, suid;
 	gid_t rgid, egid, sgid;
 	gid_t *gids;
 	int i, ngids, nnp;

 	getresuid(&ruid, &euid, &suid); /* never fails in Linux */
 	getresgid(&rgid, &egid, &sgid); /* never fails in Linux */
 	ngids = 0;
 	gids = bb_getgroups(&ngids, NULL); /* never fails in Linux */

 	nnp = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
 	if (nnp < 0)
 		bb_perror_msg_and_die("prctl: %s", "GET_NO_NEW_PRIVS");

 	printf("uid: %u\n", (unsigned)ruid);
 	printf("euid: %u\n", (unsigned)euid);
 	printf("gid: %u\n", (unsigned)rgid);
 	printf("egid: %u\n", (unsigned)egid);

 	printf("Supplementary groups: ");
 	if (ngids == 0) {
 		printf("[none]");
 	} else {
 		fmt = ",%u" + 1;
 		for (i = 0; i < ngids; i++) {
 			printf(fmt, (unsigned)gids[i]);
 			fmt = ",%u";
 		}
 	}
 	printf("\nno_new_privs: %d\n", nnp);

 # if ENABLE_FEATURE_SETPRIV_CAPABILITIES
 	getcaps(&caps);
 	printf("Inheritable capabilities: ");
 	fmt = "";
 	for (i = 0; cap_valid(i); i++) {
 		unsigned idx = CAP_TO_INDEX(i);
 		if (idx >= caps.u32s) {
 			printf("\nindex: %u u32s: %u capability: %u\n", idx, caps.u32s, i);
 			bb_simple_error_msg_and_die("unsupported capability");
 		}
 		if (caps.data[idx].inheritable & CAP_TO_MASK(i)) {
 			printf_cap(fmt, i);
 			fmt = ",";
 		}
 	}
 	if (!fmt[0])
 		printf("[none]");

 	printf("\nAmbient capabilities: ");
 	fmt = "";
 	for (i = 0; cap_valid(i); i++) {
 		int ret = prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_IS_SET, (unsigned long) i, 0UL, 0UL);
 		if (ret < 0)
 			bb_perror_msg_and_die("prctl: %s", "CAP_AMBIENT_IS_SET");
 		if (ret) {
 			printf_cap(fmt, i);
 			fmt = ",";
 		}
 	}
 	if (i == 0)
 		printf("[unsupported]");
 	else if (!fmt[0])
 		printf("[none]");

 	printf("\nCapability bounding set: ");
 	fmt = "";
 	for (i = 0; cap_valid(i); i++) {
 		int ret = prctl(PR_CAPBSET_READ, (unsigned long) i, 0UL, 0UL, 0UL);
 		if (ret < 0)
 			bb_perror_msg_and_die("prctl: %s", "CAPBSET_READ");
 		if (ret) {
 			printf_cap(fmt, i);
 			fmt = ",";
 		}
 	}
 	if (!fmt[0])
 		printf("[none]");
 	bb_putchar('\n');
 # endif

 	if (ENABLE_FEATURE_CLEAN_UP)
 		free(gids);

 	return EXIT_SUCCESS;
 }
 #endif /* FEATURE_SETPRIV_DUMP */

 int setpriv_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int setpriv_main(int argc UNUSED_PARAM, char **argv)
 {
 	static const char setpriv_longopts[] ALIGN1 =
 		IF_FEATURE_SETPRIV_DUMP(
 		"dump\0"         No_argument		"d"
 		)
 		"nnp\0"          No_argument		"\xff"
 		"no-new-privs\0" No_argument		"\xff"
 		IF_FEATURE_SETPRIV_CAPABILITIES(
 		"inh-caps\0"     Required_argument	"\xfe"
 		"ambient-caps\0" Required_argument	"\xfd"
 		)
 		;
 	int opts;
 	IF_FEATURE_SETPRIV_CAPABILITIES(char *inh_caps, *ambient_caps;)

 	opts = getopt32long(argv, "+"
 		IF_FEATURE_SETPRIV_DUMP("d")
 		IF_FEATURE_SETPRIV_CAPABILITIES("\xfe:\xfd:"),
 		setpriv_longopts
 		IF_FEATURE_SETPRIV_CAPABILITIES(, &inh_caps, &ambient_caps)
 	);
 	argv += optind;

 #if ENABLE_FEATURE_SETPRIV_DUMP
 	if (opts & OPT_DUMP) {
 		if (argv[0] || (opts - OPT_DUMP) != 0)
 			bb_show_usage();
 		return dump();
 	}
 #endif
 	if (opts & OPT_NNP) {
 		if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0))
 			bb_perror_msg_and_die("prctl: %s", "SET_NO_NEW_PRIVS");
 	}

 #if ENABLE_FEATURE_SETPRIV_CAPABILITIES
 	if (opts & OPT_INH)
 		set_inh_caps(inh_caps);
 	if (opts & OPT_AMB)
 		set_ambient_caps(ambient_caps);
 #endif

 	if (!argv[0])
 		bb_show_usage();
 	BB_EXECVP_or_die(argv);
 }
	/* vi: set sw=4 ts=4: */
	/*
	* setpriv implementation for busybox based on linux-utils-ng 2.29
	*
	* Copyright (C) 2017 by <assafgordon@gmail.com>
	*
	* Licensed under GPLv2 or later, see file LICENSE in this source tree.
	*/
	//config:config SETPRIV
	//config: bool "setpriv (6.6 kb)"
	//config: default y
	//config: select PLATFORM_LINUX
	//config: select LONG_OPTS
	//config: help
	//config: Run a program with different Linux privilege settings.
	//config: Requires kernel >= 3.5
	//config:
	//config:config FEATURE_SETPRIV_DUMP
	//config: bool "Support dumping current privilege state"
	//config: default y
	//config: depends on SETPRIV
	//config: help
	//config: Enables the "--dump" switch to print out the current privilege
	//config: state. This is helpful for diagnosing problems.
	//config:
	//config:config FEATURE_SETPRIV_CAPABILITIES
	//config: bool "Support capabilities"
	//config: default y
	//config: depends on SETPRIV
	//config: help
	//config: Capabilities can be used to grant processes additional rights
	//config: without the necessity to always execute as the root user.
	//config: Enabling this option enables "--dump" to show information on
	//config: capabilities.
	//config:
	//config:config FEATURE_SETPRIV_CAPABILITY_NAMES
	//config: bool "Support capability names"
	//config: default y
	//config: depends on SETPRIV && FEATURE_SETPRIV_CAPABILITIES
	//config: help
	//config: Capabilities can be either referenced via a human-readble name,
	//config: e.g. "net_admin", or using their index, e.g. "cap_12". Enabling
	//config: this option allows using the human-readable names in addition to
	//config: the index-based names.

	//applet:IF_SETPRIV(APPLET(setpriv, BB_DIR_BIN, BB_SUID_DROP))

	//kbuild:lib-$(CONFIG_SETPRIV) += setpriv.o

	//usage:#define setpriv_trivial_usage
	//usage: "[OPTIONS] PROG [ARGS]"
	//usage:#define setpriv_full_usage "\n\n"
	//usage: "Run PROG with different privilege settings\n"
	//usage: IF_FEATURE_SETPRIV_DUMP(
	//usage: "\n-d,--dump Show current capabilities"
	//usage: )
	//usage: "\n--nnp,--no-new-privs Ignore setuid/setgid bits and file capabilities"
	//usage: IF_FEATURE_SETPRIV_CAPABILITIES(
	//usage: "\n--inh-caps CAP,CAP Set inheritable capabilities"
	//usage: "\n--ambient-caps CAP,CAP Set ambient capabilities"
	//usage: )

	//setpriv from util-linux 2.28:
	// -d, --dump show current state (and do not exec anything)
	// --nnp, --no-new-privs disallow granting new privileges
	// --inh-caps <caps,...> set inheritable capabilities
	// --bounding-set <caps> set capability bounding set
	// --ruid <uid> set real uid
	// --euid <uid> set effective uid
	// --rgid <gid> set real gid
	// --egid <gid> set effective gid
	// --reuid <uid> set real and effective uid
	// --regid <gid> set real and effective gid
	// --clear-groups clear supplementary groups
	// --keep-groups keep supplementary groups
	// --groups <group,...> set supplementary groups
	// --securebits <bits> set securebits
	// --selinux-label <label> set SELinux label
	// --apparmor-profile <pr> set AppArmor profile

	#if ENABLE_FEATURE_SETPRIV_CAPABILITIES
	#include <linux/capability.h>
	// #include <sys/capability.h>
	// This header is in libcap, but the functions are in libc.
	// Comment in the header says this above capset/capget:
	/* system calls - look to libc for function to system call mapping */
	extern int capset(cap_user_header_t header, cap_user_data_t data);
	extern int capget(cap_user_header_t header, const cap_user_data_t data);
	// so for bbox, let's just repeat the declarations.
	// This way, libcap needs not be installed in build environment.
	#endif
	#include <sys/prctl.h>
	#include "libbb.h"

	#ifndef PR_CAPBSET_READ
	#define PR_CAPBSET_READ 23
	#endif

	#ifndef PR_SET_NO_NEW_PRIVS
	#define PR_SET_NO_NEW_PRIVS 38
	#endif

	#ifndef PR_GET_NO_NEW_PRIVS
	#define PR_GET_NO_NEW_PRIVS 39
	#endif

	#ifndef PR_CAP_AMBIENT
	#define PR_CAP_AMBIENT 47
	#define PR_CAP_AMBIENT_IS_SET 1
	#define PR_CAP_AMBIENT_RAISE 2
	#define PR_CAP_AMBIENT_LOWER 3
	#endif

	enum {
	IF_FEATURE_SETPRIV_DUMP(OPTBIT_DUMP,)
	IF_FEATURE_SETPRIV_CAPABILITIES(OPTBIT_INH,)
	IF_FEATURE_SETPRIV_CAPABILITIES(OPTBIT_AMB,)
	OPTBIT_NNP,

	IF_FEATURE_SETPRIV_DUMP(OPT_DUMP = (1 << OPTBIT_DUMP),)
	IF_FEATURE_SETPRIV_CAPABILITIES(OPT_INH = (1 << OPTBIT_INH),)
	IF_FEATURE_SETPRIV_CAPABILITIES(OPT_AMB = (1 << OPTBIT_AMB),)
	OPT_NNP = (1 << OPTBIT_NNP),
	};

	#if ENABLE_FEATURE_SETPRIV_CAPABILITIES
	DEFINE_STRUCT_CAPS;

	static unsigned parse_cap(const char *cap)
	{
	switch (cap[0]) {
	case '-':
	break;
	case '+':
	break;
	default:
	bb_error_msg_and_die("invalid capability '%s'", cap);
	break;
	}

	cap++;
	return cap_name_to_number(cap);
	}

	static void set_inh_caps(char *capstring)
	{
	struct caps caps;

	getcaps(&caps);

	capstring = strtok(capstring, ",");
	while (capstring) {
	unsigned cap;

	cap = parse_cap(capstring);
	if (CAP_TO_INDEX(cap) >= caps.u32s)
	bb_error_msg_and_die("invalid capability '%s'", capstring);

	if (capstring[0] == '+')
	caps.data[CAP_TO_INDEX(cap)].inheritable \|= CAP_TO_MASK(cap);
	else
	caps.data[CAP_TO_INDEX(cap)].inheritable &= ~CAP_TO_MASK(cap);
	capstring = strtok(NULL, ",");
	}

	if (capset(&caps.header, caps.data) != 0)
	bb_simple_perror_msg_and_die("capset");
	}

	static void set_ambient_caps(char *string)
	{
	char *cap;

	cap = strtok(string, ",");
	while (cap) {
	unsigned idx;

	idx = parse_cap(cap);
	if (cap[0] == '+') {
	if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, idx, 0, 0) < 0)
	bb_simple_perror_msg("cap_ambient_raise");
	} else {
	if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_LOWER, idx, 0, 0) < 0)
	bb_simple_perror_msg("cap_ambient_lower");
	}
	cap = strtok(NULL, ",");
	}
	}
	#endif /* FEATURE_SETPRIV_CAPABILITIES */

	#if ENABLE_FEATURE_SETPRIV_DUMP
	# if !ENABLE_FEATURE_SETPRIV_CAPABILITY_NAMES
	# define printf_cap(pfx, cap_no) printf("%scap_%u", (pfx), (cap_no))
	# endif

	static int dump(void)
	{
	IF_FEATURE_SETPRIV_CAPABILITIES(struct caps caps;)
	const char *fmt;
	uid_t ruid, euid, suid;
	gid_t rgid, egid, sgid;
	gid_t *gids;
	int i, ngids, nnp;

	getresuid(&ruid, &euid, &suid); /* never fails in Linux */
	getresgid(&rgid, &egid, &sgid); /* never fails in Linux */
	ngids = 0;
	gids = bb_getgroups(&ngids, NULL); /* never fails in Linux */

	nnp = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
	if (nnp < 0)
	bb_perror_msg_and_die("prctl: %s", "GET_NO_NEW_PRIVS");

	printf("uid: %u\n", (unsigned)ruid);
	printf("euid: %u\n", (unsigned)euid);
	printf("gid: %u\n", (unsigned)rgid);
	printf("egid: %u\n", (unsigned)egid);

	printf("Supplementary groups: ");
	if (ngids == 0) {
	printf("[none]");
	} else {
	fmt = ",%u" + 1;
	for (i = 0; i < ngids; i++) {
	printf(fmt, (unsigned)gids[i]);
	fmt = ",%u";
	}
	}
	printf("\nno_new_privs: %d\n", nnp);

	# if ENABLE_FEATURE_SETPRIV_CAPABILITIES
	getcaps(&caps);
	printf("Inheritable capabilities: ");
	fmt = "";
	for (i = 0; cap_valid(i); i++) {
	unsigned idx = CAP_TO_INDEX(i);
	if (idx >= caps.u32s) {
	printf("\nindex: %u u32s: %u capability: %u\n", idx, caps.u32s, i);
	bb_simple_error_msg_and_die("unsupported capability");
	}
	if (caps.data[idx].inheritable & CAP_TO_MASK(i)) {
	printf_cap(fmt, i);
	fmt = ",";
	}
	}
	if (!fmt[0])
	printf("[none]");

	printf("\nAmbient capabilities: ");
	fmt = "";
	for (i = 0; cap_valid(i); i++) {
	int ret = prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_IS_SET, (unsigned long) i, 0UL, 0UL);
	if (ret < 0)
	bb_perror_msg_and_die("prctl: %s", "CAP_AMBIENT_IS_SET");
	if (ret) {
	printf_cap(fmt, i);
	fmt = ",";
	}
	}
	if (i == 0)
	printf("[unsupported]");
	else if (!fmt[0])
	printf("[none]");

	printf("\nCapability bounding set: ");
	fmt = "";
	for (i = 0; cap_valid(i); i++) {
	int ret = prctl(PR_CAPBSET_READ, (unsigned long) i, 0UL, 0UL, 0UL);
	if (ret < 0)
	bb_perror_msg_and_die("prctl: %s", "CAPBSET_READ");
	if (ret) {
	printf_cap(fmt, i);
	fmt = ",";
	}
	}
	if (!fmt[0])
	printf("[none]");
	bb_putchar('\n');
	# endif

	if (ENABLE_FEATURE_CLEAN_UP)
	free(gids);

	return EXIT_SUCCESS;
	}
	#endif /* FEATURE_SETPRIV_DUMP */

	int setpriv_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
	int setpriv_main(int argc UNUSED_PARAM, char **argv)
	{
	static const char setpriv_longopts[] ALIGN1 =
	IF_FEATURE_SETPRIV_DUMP(
	"dump\0" No_argument "d"
	)
	"nnp\0" No_argument "\xff"
	"no-new-privs\0" No_argument "\xff"
	IF_FEATURE_SETPRIV_CAPABILITIES(
	"inh-caps\0" Required_argument "\xfe"
	"ambient-caps\0" Required_argument "\xfd"
	)
	;
	int opts;
	IF_FEATURE_SETPRIV_CAPABILITIES(char inh_caps, ambient_caps;)

	opts = getopt32long(argv, "+"
	IF_FEATURE_SETPRIV_DUMP("d")
	IF_FEATURE_SETPRIV_CAPABILITIES("\xfe:\xfd:"),
	setpriv_longopts
	IF_FEATURE_SETPRIV_CAPABILITIES(, &inh_caps, &ambient_caps)
	);
	argv += optind;

	#if ENABLE_FEATURE_SETPRIV_DUMP
	if (opts & OPT_DUMP) {
	if (argv[0] \|\| (opts - OPT_DUMP) != 0)
	bb_show_usage();
	return dump();
	}
	#endif
	if (opts & OPT_NNP) {
	if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0))
	bb_perror_msg_and_die("prctl: %s", "SET_NO_NEW_PRIVS");
	}

	#if ENABLE_FEATURE_SETPRIV_CAPABILITIES
	if (opts & OPT_INH)
	set_inh_caps(inh_caps);
	if (opts & OPT_AMB)
	set_ambient_caps(ambient_caps);
	#endif

	if (!argv[0])
	bb_show_usage();
	BB_EXECVP_or_die(argv);
	}