2 # For a description of the syntax of this configuration file,
3 # see scripts/kbuild/config-language.txt.
6 mainmenu "BusyBox Configuration"
12 menu "Busybox Settings"
15 bool "Enable options for full-blown desktop systems"
18 Enable options and features which are not essential.
19 Select this if you plan to use busybox on full-blown desktop machine
20 with common Linux distro, which needs higher level of command-line
23 If you are preparing your build to be used on an embedded box
24 where you have tighter control over the entire set of userspace
25 tools, you can unselect this option for smaller code size.
28 bool "Provide compatible behavior for rare corner cases (bigger code)"
31 This option makes grep, sed etc handle rare corner cases
32 (embedded NUL bytes and such). This makes code bigger and uses
33 some GNU extensions in libc. You probably only need this option
34 if you plan to run busybox on desktop.
37 bool "Enable obsolete features removed before SUSv3"
40 This option will enable backwards compatibility with SuSv2,
41 specifically, old-style numeric options ('command -1 <file>')
42 will be supported in head, tail, and fold. (Note: should
45 config USE_PORTABLE_CODE
46 bool "Avoid using GCC-specific code constructs"
49 Use this option if you are trying to compile busybox with
50 compiler other than gcc.
51 If you do use gcc, this option may needlessly increase code size.
54 bool "Show applet usage messages"
57 Enabling this option, BusyBox applets will show terse help messages
58 when invoked with wrong arguments.
59 If you do not want to show any (helpful) usage message when
60 issuing wrong command syntax, you can say 'N' here,
61 saving approximately 7k.
63 config FEATURE_VERBOSE_USAGE
64 bool "Show verbose applet usage messages"
68 All BusyBox applets will show verbose help messages when
69 busybox is invoked with --help. This will add a lot of text to the
70 busybox binary. In the default configuration, this will add about
71 13k, but it can add much more depending on your configuration.
73 config FEATURE_COMPRESS_USAGE
74 bool "Store applet usage messages in compressed form"
78 Store usage messages in .bz compressed form, uncompress them
79 on-the-fly when <applet> --help is called.
81 If you have a really tiny busybox with few applets enabled (and
82 bunzip2 isn't one of them), the overhead of the decompressor might
83 be noticeable. Also, if you run executables directly from ROM
84 and have very little memory, this might not be a win. Otherwise,
85 you probably want this.
88 bool "Include busybox applet"
91 The busybox applet provides general help regarding busybox and
92 allows the included applets to be listed. It's also required
93 if applet links are to be installed at runtime.
95 If you can live without these features disabling this will save
98 config FEATURE_INSTALLER
99 bool "Support --install [-s] to install applet links at runtime"
103 Enable 'busybox --install [-s]' support. This will allow you to use
104 busybox at runtime to create hard links or symlinks for all the
105 applets that are compiled into busybox.
107 config INSTALL_NO_USR
108 bool "Don't use /usr"
111 Disable use of /usr. busybox --install and "make install"
112 will install applets only to /bin and /sbin,
113 never to /usr/bin or /usr/sbin.
116 bool "Support PAM (Pluggable Authentication Modules)"
119 Use PAM in some busybox applets (currently login and httpd) instead
120 of direct access to password database.
123 bool "Support --long-options"
126 Enable this if you want busybox applets to use the gnu --long-option
127 style, in addition to single character -a -b -c style options.
129 config FEATURE_DEVPTS
130 bool "Use the devpts filesystem for Unix98 PTYs"
133 Enable if you want BusyBox to use Unix98 PTY support. If enabled,
134 busybox will use /dev/ptmx for the master side of the pseudoterminal
135 and /dev/pts/<number> for the slave side. Otherwise, BSD style
136 /dev/ttyp<number> will be used. To use this option, you should have
139 config FEATURE_CLEAN_UP
140 bool "Clean up all memory before exiting (usually not needed)"
143 As a size optimization, busybox normally exits without explicitly
144 freeing dynamically allocated memory or closing files. This saves
145 space since the OS will clean up for us, but it can confuse debuggers
146 like valgrind, which report tons of memory and resource leaks.
148 Don't enable this unless you have a really good reason to clean
152 bool "Support utmp file"
155 The file /var/run/utmp is used to track who is currently logged in.
156 With this option on, certain applets (getty, login, telnetd etc)
157 will create and delete entries there.
158 "who" applet requires this option.
161 bool "Support wtmp file"
163 depends on FEATURE_UTMP
165 The file /var/run/wtmp is used to track when users have logged into
166 and logged out of the system.
167 With this option on, certain applets (getty, login, telnetd etc)
168 will append new entries there.
169 "last" applet requires this option.
171 config FEATURE_PIDFILE
172 bool "Support writing pidfiles"
175 This option makes some applets (e.g. crond, syslogd, inetd) write
176 a pidfile at the configured PID_FILE_PATH. It has no effect
177 on applets which require pidfiles to run.
180 string "Path to directory for pidfile"
182 depends on FEATURE_PIDFILE
184 This is the default path where pidfiles are created. Applets which
185 allow you to set the pidfile path on the command line will override
186 this value. The option has no effect on applets that require you to
187 specify a pidfile path.
190 bool "Support SUID/SGID handling"
193 With this option you can install the busybox binary belonging
194 to root with the suid bit set, enabling some applets to perform
195 root-level operations even when run by ordinary users
196 (for example, mounting of user mounts in fstab needs this).
198 Busybox will automatically drop privileges for applets
199 that don't need root access.
201 If you are really paranoid and don't want to do this, build two
202 busybox binaries with different applets in them (and the appropriate
203 symlinks pointing to each binary), and only set the suid bit on the
206 The applets which require root rights (need suid bit or
207 to be run by root) and will refuse to execute otherwise:
208 crontab, login, passwd, su, vlock, wall.
210 The applets which will use root rights if they have them
211 (via suid bit, or because run by root), but would try to work
212 without root right nevertheless:
213 findfs, ping[6], traceroute[6], mount.
215 Note that if you DONT select this option, but DO make busybox
216 suid root, ALL applets will run under root, which is a huge
217 security hole (think "cp /some/file /etc/passwd").
219 config FEATURE_SUID_CONFIG
220 bool "Runtime SUID/SGID configuration via /etc/busybox.conf"
222 depends on FEATURE_SUID
224 Allow the SUID / SGID state of an applet to be determined at runtime
225 by checking /etc/busybox.conf. (This is sort of a poor man's sudo.)
226 The format of this file is as follows:
228 APPLET = [Ssx-][Ssx-][x-] [USER.GROUP]
230 s: USER or GROUP is allowed to execute APPLET.
231 APPLET will run under USER or GROUP
232 (reagardless of who's running it).
233 S: USER or GROUP is NOT allowed to execute APPLET.
234 APPLET will run under USER or GROUP.
235 This option is not very sensical.
236 x: USER/GROUP/others are allowed to execute APPLET.
237 No UID/GID change will be done when it is run.
238 -: USER/GROUP/others are not allowed to execute APPLET.
240 An example might help:
243 su = ssx root.0 # applet su can be run by anyone and runs with
245 su = ssx # exactly the same
247 mount = sx- root.disk # applet mount can be run by root and members
248 # of group disk (but not anyone else)
249 # and runs with euid=0 (egid is not changed)
251 cp = --- # disable applet cp for everyone
253 The file has to be owned by user root, group root and has to be
254 writeable only by root:
255 (chown 0.0 /etc/busybox.conf; chmod 600 /etc/busybox.conf)
256 The busybox executable has to be owned by user root, group
257 root and has to be setuid root for this to work:
258 (chown 0.0 /bin/busybox; chmod 4755 /bin/busybox)
260 Robert 'sandman' Griebl has more information here:
261 <url: http://www.softforge.de/bb/suid.html >.
263 config FEATURE_SUID_CONFIG_QUIET
264 bool "Suppress warning message if /etc/busybox.conf is not readable"
266 depends on FEATURE_SUID_CONFIG
268 /etc/busybox.conf should be readable by the user needing the SUID,
269 check this option to avoid users to be notified about missing
273 bool "Support NSA Security Enhanced Linux"
275 select PLATFORM_LINUX
277 Enable support for SELinux in applets ls, ps, and id. Also provide
278 the option of compiling in SELinux applets.
280 If you do not have a complete SELinux userland installed, this stuff
281 will not compile. Specifially, libselinux 1.28 or better is
282 directly required by busybox. If the installation is located in a
283 non-standard directory, provide it by invoking make as follows:
284 CFLAGS=-I<libselinux-include-path> \
285 LDFLAGS=-L<libselinux-lib-path> \
288 Most people will leave this set to 'N'.
290 config FEATURE_PREFER_APPLETS
291 bool "exec prefers applets"
294 This is an experimental option which directs applets about to
295 call 'exec' to try and find an applicable busybox applet before
296 searching the PATH. This is typically done by exec'ing
298 This may affect shell, find -exec, xargs and similar applets.
299 They will use applets even if /bin/<applet> -> busybox link
300 is missing (or is not a link to busybox). However, this causes
301 problems in chroot jails without mounted /proc and with ps/top
302 (command name can be shown as 'exe' for applets started this way).
304 config BUSYBOX_EXEC_PATH
305 string "Path to BusyBox executable"
306 default "/proc/self/exe"
308 When Busybox applets need to run other busybox applets, BusyBox
309 sometimes needs to exec() itself. When the /proc filesystem is
310 mounted, /proc/self/exe always points to the currently running
311 executable. If you haven't got /proc, set this to wherever you
312 want to run BusyBox from.
314 # These are auto-selected by other options
316 config FEATURE_SYSLOG
317 bool #No description makes it a hidden option
320 # This option is auto-selected when you select any applet which may
321 # send its output to syslog. You do not need to select it manually.
323 config FEATURE_HAVE_RPC
324 bool #No description makes it a hidden option
327 # This is automatically selected if any of enabled applets need it.
328 # You do not need to select it manually.
330 config PLATFORM_LINUX
331 bool #No description makes it a hidden option
334 # For the most part, busybox requires only POSIX compatibility
335 # from the target system, but some applets and features use
336 # Linux-specific interfaces.
338 # This is automatically selected if any applet or feature requires
339 # Linux-specific interfaces. You do not need to select it manually.
341 comment 'Build Options'
344 bool "Build BusyBox as a static binary (no shared libs)"
347 If you want to build a static BusyBox binary, which does not
348 use or require any shared libraries, then enable this option.
349 This can cause BusyBox to be considerably larger, so you should
350 leave this option false unless you have a good reason (i.e.
351 your target platform does not support shared libraries, or
352 you are building an initrd which doesn't need anything but
355 Most people will leave this set to 'N'.
358 bool "Build BusyBox as a position independent executable"
362 Hardened code option. PIE binaries are loaded at a different
363 address at each invocation. This has some overhead,
364 particularly on x86-32 which is short on registers.
366 Most people will leave this set to 'N'.
369 bool "Force NOMMU build"
372 Busybox tries to detect whether architecture it is being
373 built against supports MMU or not. If this detection fails,
374 or if you want to build NOMMU version of busybox for testing,
375 you may force NOMMU build here.
377 Most people will leave this set to 'N'.
379 # PIE can be made to work with BUILD_LIBBUSYBOX, but currently
380 # build system does not support that
381 config BUILD_LIBBUSYBOX
382 bool "Build shared libbusybox"
384 depends on !FEATURE_PREFER_APPLETS && !PIE && !STATIC
386 Build a shared library libbusybox.so.N.N.N which contains all
389 This feature allows every applet to be built as a really tiny
390 separate executable linked against the library:
392 text data bss dec hex filename
393 939 212 28 1179 49b 0_lib/last
394 939 212 28 1179 49b 0_lib/less
395 919138 8328 1556 929022 e2cfe 0_lib/libbusybox.so.1.N.M
397 This is useful on NOMMU systems which are not capable
398 of sharing executables, but are capable of sharing code
399 in dynamic libraries.
401 config FEATURE_LIBBUSYBOX_STATIC
402 bool "Pull in all external references into libbusybox"
404 depends on BUILD_LIBBUSYBOX
406 Make libbusybox library independent, not using or requiring
407 any other shared libraries.
409 config FEATURE_INDIVIDUAL
410 bool "Produce a binary for each applet, linked against libbusybox"
412 depends on BUILD_LIBBUSYBOX
414 If your CPU architecture doesn't allow for sharing text/rodata
415 sections of running binaries, but allows for runtime dynamic
416 libraries, this option will allow you to reduce memory footprint
417 when you have many different applets running at once.
419 If your CPU architecture allows for sharing text/rodata,
420 having single binary is more optimal.
422 Each applet will be a tiny program, dynamically linked
423 against libbusybox.so.N.N.N.
425 You need to have a working dynamic linker.
427 config FEATURE_SHARED_BUSYBOX
428 bool "Produce additional busybox binary linked against libbusybox"
430 depends on BUILD_LIBBUSYBOX
432 Build busybox, dynamically linked against libbusybox.so.N.N.N.
434 You need to have a working dynamic linker.
436 ### config BUILD_AT_ONCE
437 ### bool "Compile all sources at once"
440 ### Normally each source-file is compiled with one invocation of
442 ### If you set this option, all sources are compiled at once.
443 ### This gives the compiler more opportunities to optimize which can
444 ### result in smaller and/or faster binaries.
446 ### Setting this option will consume alot of memory, e.g. if you
447 ### enable all applets with all features, gcc uses more than 300MB
448 ### RAM during compilation of busybox.
450 ### This option is most likely only beneficial for newer compilers
451 ### such as gcc-4.1 and above.
453 ### Say 'N' unless you know what you are doing.
456 bool "Build with Large File Support (for accessing files > 2 GB)"
459 If you want to build BusyBox with large file support, then enable
460 this option. This will have no effect if your kernel or your C
461 library lacks large file support for large files. Some of the
462 programs that can benefit from large file support include dd, gzip,
463 cp, mount, tar, and many others. If you want to access files larger
464 than 2 Gigabytes, enable this option. Otherwise, leave it set to 'N'.
466 config CROSS_COMPILER_PREFIX
467 string "Cross Compiler prefix"
470 If you want to build BusyBox with a cross compiler, then you
471 will need to set this to the cross-compiler prefix, for example,
474 Note that CROSS_COMPILE environment variable or
475 "make CROSS_COMPILE=xxx ..." will override this selection.
477 Native builds leave this empty.
480 string "Path to sysroot"
483 If you want to build BusyBox with a cross compiler, then you
484 might also need to specify where /usr/include and /usr/lib
487 For example, BusyBox can be built against an installed
488 Android NDK, platform version 9, for ARM ABI with
490 CONFIG_SYSROOT=/opt/android-ndk/platforms/android-9/arch-arm
492 Native builds leave this empty.
495 string "Additional CFLAGS"
498 Additional CFLAGS to pass to the compiler verbatim.
501 string "Additional LDFLAGS"
504 Additional LDFLAGS to pass to the linker verbatim.
507 string "Additional LDLIBS"
510 Additional LDLIBS to pass to the linker with -l.
512 comment 'Installation Options ("make install" behavior)'
515 prompt "What kind of applet links to install"
516 default INSTALL_APPLET_SYMLINKS
518 Choose what kind of links to applets are created by "make install".
520 config INSTALL_APPLET_SYMLINKS
523 Install applets as soft-links to the busybox binary. This needs some
524 free inodes on the filesystem, but might help with filesystem
525 generators that can't cope with hard-links.
527 config INSTALL_APPLET_HARDLINKS
530 Install applets as hard-links to the busybox binary. This might
531 count on a filesystem with few inodes.
533 config INSTALL_APPLET_SCRIPT_WRAPPERS
534 bool "as script wrappers"
536 Install applets as script wrappers that call the busybox binary.
538 config INSTALL_APPLET_DONT
541 Do not install applet links. Useful when you plan to use
542 busybox --install for installing links, or plan to use
543 a standalone shell and thus don't need applet links.
548 prompt "/bin/sh applet link"
549 default INSTALL_SH_APPLET_SYMLINK
550 depends on INSTALL_APPLET_SCRIPT_WRAPPERS
552 Choose how you install /bin/sh applet link.
554 config INSTALL_SH_APPLET_SYMLINK
557 Install /bin/sh applet as soft-link to the busybox binary.
559 config INSTALL_SH_APPLET_HARDLINK
562 Install /bin/sh applet as hard-link to the busybox binary.
564 config INSTALL_SH_APPLET_SCRIPT_WRAPPER
565 bool "as script wrapper"
567 Install /bin/sh applet as script wrapper that calls
573 string "BusyBox installation prefix"
576 Define your directory to install BusyBox files/subdirs in.
578 comment 'Debugging Options'
581 bool "Build BusyBox with extra Debugging symbols"
584 Say Y here if you wish to examine BusyBox internals while applets are
585 running. This increases the size of the binary considerably, and
586 should only be used when doing development. If you are doing
587 development and want to debug BusyBox, answer Y.
589 Most people should answer N.
591 config DEBUG_PESSIMIZE
592 bool "Disable compiler optimizations"
596 The compiler's optimization of source code can eliminate and reorder
597 code, resulting in an executable that's hard to understand when
598 stepping through it with a debugger. This switches it off, resulting
599 in a much bigger executable that more closely matches the source
602 config DEBUG_SANITIZE
603 bool "Enable runtime sanitizers (ASAN/LSAN/USAN/etc...)"
606 Say Y here if you want to enable runtime sanitizers. These help
607 catch bad memory accesses (e.g. buffer overflows), but will make
608 the executable larger and slow down runtime a bit.
610 This adds -fsanitize=foo options to gcc command line.
612 If you aren't developing/testing busybox, say N here.
615 bool "Build unit tests"
618 Say Y here if you want to build unit tests (both the framework and
619 test cases) as a Busybox applet. This results in bigger code, so you
620 probably don't want this option in production builds.
623 bool "Abort compilation on any warning"
626 This adds -Werror to gcc command line.
628 Most people should answer N.
631 prompt "Additional debugging library"
634 Using an additional debugging library will make BusyBox become
635 considerable larger and will cause it to run more slowly. You
636 should always leave this option disabled for production use.
640 This enables compiling with dmalloc ( http://dmalloc.com/ )
641 which is an excellent public domain mem leak and malloc problem
642 detector. To enable dmalloc, before running busybox you will
643 want to properly set your environment, for example:
644 export DMALLOC_OPTIONS=debug=0x34f47d83,inter=100,log=logfile
645 The 'debug=' value is generated using the following command
646 dmalloc -p log-stats -p log-non-free -p log-bad-space \
647 -p log-elapsed-time -p check-fence -p check-heap \
648 -p check-lists -p check-blank -p check-funcs -p realloc-copy \
651 Electric-fence support:
652 -----------------------
653 This enables compiling with Electric-fence support. Electric
654 fence is another very useful malloc debugging library which uses
655 your computer's virtual memory hardware to detect illegal memory
656 accesses. This support will make BusyBox be considerable larger
657 and run slower, so you should leave this option disabled unless
658 you are hunting a hard to find memory problem.
668 bool "Electric-fence"
674 source libbb/Config.in
678 source archival/Config.in
679 source coreutils/Config.in
680 source console-tools/Config.in
681 source debianutils/Config.in
682 source editors/Config.in
683 source findutils/Config.in
684 source init/Config.in
685 source loginutils/Config.in
686 source e2fsprogs/Config.in
687 source modutils/Config.in
688 source util-linux/Config.in
689 source miscutils/Config.in
690 source networking/Config.in
691 source printutils/Config.in
692 source mailutils/Config.in
693 source procps/Config.in
694 source runit/Config.in
695 source selinux/Config.in
696 source shell/Config.in
697 source sysklogd/Config.in