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. If you unselect
94 this option, running busybox without any arguments will give
95 just a cryptic error message:
98 busybox: applet not found
100 Running "busybox APPLET [ARGS...]" will still work, of course.
102 config FEATURE_INSTALLER
103 bool "Support --install [-s] to install applet links at runtime"
107 Enable 'busybox --install [-s]' support. This will allow you to use
108 busybox at runtime to create hard links or symlinks for all the
109 applets that are compiled into busybox.
111 config INSTALL_NO_USR
112 bool "Don't use /usr"
115 Disable use of /usr. busybox --install and "make install"
116 will install applets only to /bin and /sbin,
117 never to /usr/bin or /usr/sbin.
120 bool "Build with Large File Support (for accessing files > 2 GB)"
123 If you want to build BusyBox with large file support, then enable
124 this option. This will have no effect if your kernel or your C
125 library lacks large file support for large files. Some of the
126 programs that can benefit from large file support include dd, gzip,
127 cp, mount, tar, and many others. If you want to access files larger
128 than 2 Gigabytes, enable this option. Otherwise, leave it set to 'N'.
131 bool "Support PAM (Pluggable Authentication Modules)"
134 Use PAM in some busybox applets (currently login and httpd) instead
135 of direct access to password database.
138 bool "Support --long-options"
141 Enable this if you want busybox applets to use the gnu --long-option
142 style, in addition to single character -a -b -c style options.
144 config FEATURE_DEVPTS
145 bool "Use the devpts filesystem for Unix98 PTYs"
148 Enable if you want BusyBox to use Unix98 PTY support. If enabled,
149 busybox will use /dev/ptmx for the master side of the pseudoterminal
150 and /dev/pts/<number> for the slave side. Otherwise, BSD style
151 /dev/ttyp<number> will be used. To use this option, you should have
155 bool "Support utmp file"
158 The file /var/run/utmp is used to track who is currently logged in.
159 With this option on, certain applets (getty, login, telnetd etc)
160 will create and delete entries there.
161 "who" applet requires this option.
164 bool "Support wtmp file"
166 depends on FEATURE_UTMP
168 The file /var/run/wtmp is used to track when users have logged into
169 and logged out of the system.
170 With this option on, certain applets (getty, login, telnetd etc)
171 will append new entries there.
172 "last" applet requires this option.
174 config FEATURE_PIDFILE
175 bool "Support writing pidfiles"
178 This option makes some applets (e.g. crond, syslogd, inetd) write
179 a pidfile at the configured PID_FILE_PATH. It has no effect
180 on applets which require pidfiles to run.
183 string "Directory for pidfiles"
185 depends on FEATURE_PIDFILE
187 This is the default path where pidfiles are created. Applets which
188 allow you to set the pidfile path on the command line will override
189 this value. The option has no effect on applets that require you to
190 specify a pidfile path.
193 bool "Support SUID/SGID handling"
196 With this option you can install the busybox binary belonging
197 to root with the suid bit set, enabling some applets to perform
198 root-level operations even when run by ordinary users
199 (for example, mounting of user mounts in fstab needs this).
201 Busybox will automatically drop privileges for applets
202 that don't need root access.
204 If you are really paranoid and don't want to do this, build two
205 busybox binaries with different applets in them (and the appropriate
206 symlinks pointing to each binary), and only set the suid bit on the
209 The applets which require root rights (need suid bit or
210 to be run by root) and will refuse to execute otherwise:
211 crontab, login, passwd, su, vlock, wall.
213 The applets which will use root rights if they have them
214 (via suid bit, or because run by root), but would try to work
215 without root right nevertheless:
216 findfs, ping[6], traceroute[6], mount.
218 Note that if you DONT select this option, but DO make busybox
219 suid root, ALL applets will run under root, which is a huge
220 security hole (think "cp /some/file /etc/passwd").
222 config FEATURE_SUID_CONFIG
223 bool "Runtime SUID/SGID configuration via /etc/busybox.conf"
225 depends on FEATURE_SUID
227 Allow the SUID / SGID state of an applet to be determined at runtime
228 by checking /etc/busybox.conf. (This is sort of a poor man's sudo.)
229 The format of this file is as follows:
231 APPLET = [Ssx-][Ssx-][x-] [USER.GROUP]
233 s: USER or GROUP is allowed to execute APPLET.
234 APPLET will run under USER or GROUP
235 (reagardless of who's running it).
236 S: USER or GROUP is NOT allowed to execute APPLET.
237 APPLET will run under USER or GROUP.
238 This option is not very sensical.
239 x: USER/GROUP/others are allowed to execute APPLET.
240 No UID/GID change will be done when it is run.
241 -: USER/GROUP/others are not allowed to execute APPLET.
243 An example might help:
246 su = ssx root.0 # applet su can be run by anyone and runs with
248 su = ssx # exactly the same
250 mount = sx- root.disk # applet mount can be run by root and members
251 # of group disk (but not anyone else)
252 # and runs with euid=0 (egid is not changed)
254 cp = --- # disable applet cp for everyone
256 The file has to be owned by user root, group root and has to be
257 writeable only by root:
258 (chown 0.0 /etc/busybox.conf; chmod 600 /etc/busybox.conf)
259 The busybox executable has to be owned by user root, group
260 root and has to be setuid root for this to work:
261 (chown 0.0 /bin/busybox; chmod 4755 /bin/busybox)
263 Robert 'sandman' Griebl has more information here:
264 <url: http://www.softforge.de/bb/suid.html >.
266 config FEATURE_SUID_CONFIG_QUIET
267 bool "Suppress warning message if /etc/busybox.conf is not readable"
269 depends on FEATURE_SUID_CONFIG
271 /etc/busybox.conf should be readable by the user needing the SUID,
272 check this option to avoid users to be notified about missing
275 config FEATURE_PREFER_APPLETS
276 bool "exec prefers applets"
279 This is an experimental option which directs applets about to
280 call 'exec' to try and find an applicable busybox applet before
281 searching the PATH. This is typically done by exec'ing
283 This may affect shell, find -exec, xargs and similar applets.
284 They will use applets even if /bin/<applet> -> busybox link
285 is missing (or is not a link to busybox). However, this causes
286 problems in chroot jails without mounted /proc and with ps/top
287 (command name can be shown as 'exe' for applets started this way).
289 config BUSYBOX_EXEC_PATH
290 string "Path to BusyBox executable"
291 default "/proc/self/exe"
293 When Busybox applets need to run other busybox applets, BusyBox
294 sometimes needs to exec() itself. When the /proc filesystem is
295 mounted, /proc/self/exe always points to the currently running
296 executable. If you haven't got /proc, set this to wherever you
297 want to run BusyBox from.
300 bool "Support NSA Security Enhanced Linux"
302 select PLATFORM_LINUX
304 Enable support for SELinux in applets ls, ps, and id. Also provide
305 the option of compiling in SELinux applets.
307 If you do not have a complete SELinux userland installed, this stuff
308 will not compile. Specifially, libselinux 1.28 or better is
309 directly required by busybox. If the installation is located in a
310 non-standard directory, provide it by invoking make as follows:
311 CFLAGS=-I<libselinux-include-path> \
312 LDFLAGS=-L<libselinux-lib-path> \
315 Most people will leave this set to 'N'.
317 config FEATURE_CLEAN_UP
318 bool "Clean up all memory before exiting (usually not needed)"
321 As a size optimization, busybox normally exits without explicitly
322 freeing dynamically allocated memory or closing files. This saves
323 space since the OS will clean up for us, but it can confuse debuggers
324 like valgrind, which report tons of memory and resource leaks.
326 Don't enable this unless you have a really good reason to clean
329 # These are auto-selected by other options
331 config FEATURE_SYSLOG
332 bool #No description makes it a hidden option
335 # This option is auto-selected when you select any applet which may
336 # send its output to syslog. You do not need to select it manually.
338 config FEATURE_HAVE_RPC
339 bool #No description makes it a hidden option
342 # This is automatically selected if any of enabled applets need it.
343 # You do not need to select it manually.
345 config PLATFORM_LINUX
346 bool #No description makes it a hidden option
349 # For the most part, busybox requires only POSIX compatibility
350 # from the target system, but some applets and features use
351 # Linux-specific interfaces.
353 # This is automatically selected if any applet or feature requires
354 # Linux-specific interfaces. You do not need to select it manually.
356 comment 'Build Options'
359 bool "Build BusyBox as a static binary (no shared libs)"
362 If you want to build a static BusyBox binary, which does not
363 use or require any shared libraries, then enable this option.
364 This can cause BusyBox to be considerably larger, so you should
365 leave this option false unless you have a good reason (i.e.
366 your target platform does not support shared libraries, or
367 you are building an initrd which doesn't need anything but
370 Most people will leave this set to 'N'.
373 bool "Build BusyBox as a position independent executable"
377 Hardened code option. PIE binaries are loaded at a different
378 address at each invocation. This has some overhead,
379 particularly on x86-32 which is short on registers.
381 Most people will leave this set to 'N'.
384 bool "Force NOMMU build"
387 Busybox tries to detect whether architecture it is being
388 built against supports MMU or not. If this detection fails,
389 or if you want to build NOMMU version of busybox for testing,
390 you may force NOMMU build here.
392 Most people will leave this set to 'N'.
394 # PIE can be made to work with BUILD_LIBBUSYBOX, but currently
395 # build system does not support that
396 config BUILD_LIBBUSYBOX
397 bool "Build shared libbusybox"
399 depends on !FEATURE_PREFER_APPLETS && !PIE && !STATIC
401 Build a shared library libbusybox.so.N.N.N which contains all
404 This feature allows every applet to be built as a really tiny
405 separate executable linked against the library:
407 text data bss dec hex filename
408 939 212 28 1179 49b 0_lib/last
409 939 212 28 1179 49b 0_lib/less
410 919138 8328 1556 929022 e2cfe 0_lib/libbusybox.so.1.N.M
412 This is useful on NOMMU systems which are not capable
413 of sharing executables, but are capable of sharing code
414 in dynamic libraries.
416 config FEATURE_LIBBUSYBOX_STATIC
417 bool "Pull in all external references into libbusybox"
419 depends on BUILD_LIBBUSYBOX
421 Make libbusybox library independent, not using or requiring
422 any other shared libraries.
424 config FEATURE_INDIVIDUAL
425 bool "Produce a binary for each applet, linked against libbusybox"
427 depends on BUILD_LIBBUSYBOX
429 If your CPU architecture doesn't allow for sharing text/rodata
430 sections of running binaries, but allows for runtime dynamic
431 libraries, this option will allow you to reduce memory footprint
432 when you have many different applets running at once.
434 If your CPU architecture allows for sharing text/rodata,
435 having single binary is more optimal.
437 Each applet will be a tiny program, dynamically linked
438 against libbusybox.so.N.N.N.
440 You need to have a working dynamic linker.
442 config FEATURE_SHARED_BUSYBOX
443 bool "Produce additional busybox binary linked against libbusybox"
445 depends on BUILD_LIBBUSYBOX
447 Build busybox, dynamically linked against libbusybox.so.N.N.N.
449 You need to have a working dynamic linker.
451 ### config BUILD_AT_ONCE
452 ### bool "Compile all sources at once"
455 ### Normally each source-file is compiled with one invocation of
457 ### If you set this option, all sources are compiled at once.
458 ### This gives the compiler more opportunities to optimize which can
459 ### result in smaller and/or faster binaries.
461 ### Setting this option will consume alot of memory, e.g. if you
462 ### enable all applets with all features, gcc uses more than 300MB
463 ### RAM during compilation of busybox.
465 ### This option is most likely only beneficial for newer compilers
466 ### such as gcc-4.1 and above.
468 ### Say 'N' unless you know what you are doing.
470 config CROSS_COMPILER_PREFIX
471 string "Cross Compiler prefix"
474 If you want to build BusyBox with a cross compiler, then you
475 will need to set this to the cross-compiler prefix, for example,
478 Note that CROSS_COMPILE environment variable or
479 "make CROSS_COMPILE=xxx ..." will override this selection.
481 Native builds leave this empty.
484 string "Path to sysroot"
487 If you want to build BusyBox with a cross compiler, then you
488 might also need to specify where /usr/include and /usr/lib
491 For example, BusyBox can be built against an installed
492 Android NDK, platform version 9, for ARM ABI with
494 CONFIG_SYSROOT=/opt/android-ndk/platforms/android-9/arch-arm
496 Native builds leave this empty.
499 string "Additional CFLAGS"
502 Additional CFLAGS to pass to the compiler verbatim.
505 string "Additional LDFLAGS"
508 Additional LDFLAGS to pass to the linker verbatim.
511 string "Additional LDLIBS"
514 Additional LDLIBS to pass to the linker with -l.
516 comment 'Installation Options ("make install" behavior)'
519 prompt "What kind of applet links to install"
520 default INSTALL_APPLET_SYMLINKS
522 Choose what kind of links to applets are created by "make install".
524 config INSTALL_APPLET_SYMLINKS
527 Install applets as soft-links to the busybox binary. This needs some
528 free inodes on the filesystem, but might help with filesystem
529 generators that can't cope with hard-links.
531 config INSTALL_APPLET_HARDLINKS
534 Install applets as hard-links to the busybox binary. This might
535 count on a filesystem with few inodes.
537 config INSTALL_APPLET_SCRIPT_WRAPPERS
538 bool "as script wrappers"
540 Install applets as script wrappers that call the busybox binary.
542 config INSTALL_APPLET_DONT
545 Do not install applet links. Useful when you plan to use
546 busybox --install for installing links, or plan to use
547 a standalone shell and thus don't need applet links.
552 prompt "/bin/sh applet link"
553 default INSTALL_SH_APPLET_SYMLINK
554 depends on INSTALL_APPLET_SCRIPT_WRAPPERS
556 Choose how you install /bin/sh applet link.
558 config INSTALL_SH_APPLET_SYMLINK
561 Install /bin/sh applet as soft-link to the busybox binary.
563 config INSTALL_SH_APPLET_HARDLINK
566 Install /bin/sh applet as hard-link to the busybox binary.
568 config INSTALL_SH_APPLET_SCRIPT_WRAPPER
569 bool "as script wrapper"
571 Install /bin/sh applet as script wrapper that calls
577 string "BusyBox installation prefix"
580 Define your directory to install BusyBox files/subdirs in.
582 comment 'Debugging Options'
585 bool "Build BusyBox with extra Debugging symbols"
588 Say Y here if you wish to examine BusyBox internals while applets are
589 running. This increases the size of the binary considerably, and
590 should only be used when doing development. If you are doing
591 development and want to debug BusyBox, answer Y.
593 Most people should answer N.
595 config DEBUG_PESSIMIZE
596 bool "Disable compiler optimizations"
600 The compiler's optimization of source code can eliminate and reorder
601 code, resulting in an executable that's hard to understand when
602 stepping through it with a debugger. This switches it off, resulting
603 in a much bigger executable that more closely matches the source
606 config DEBUG_SANITIZE
607 bool "Enable runtime sanitizers (ASAN/LSAN/USAN/etc...)"
610 Say Y here if you want to enable runtime sanitizers. These help
611 catch bad memory accesses (e.g. buffer overflows), but will make
612 the executable larger and slow down runtime a bit.
614 This adds -fsanitize=foo options to gcc command line.
616 If you aren't developing/testing busybox, say N here.
619 bool "Build unit tests"
622 Say Y here if you want to build unit tests (both the framework and
623 test cases) as a Busybox applet. This results in bigger code, so you
624 probably don't want this option in production builds.
627 bool "Abort compilation on any warning"
630 This adds -Werror to gcc command line.
632 Most people should answer N.
635 prompt "Additional debugging library"
638 Using an additional debugging library will make BusyBox become
639 considerable larger and will cause it to run more slowly. You
640 should always leave this option disabled for production use.
644 This enables compiling with dmalloc ( http://dmalloc.com/ )
645 which is an excellent public domain mem leak and malloc problem
646 detector. To enable dmalloc, before running busybox you will
647 want to properly set your environment, for example:
648 export DMALLOC_OPTIONS=debug=0x34f47d83,inter=100,log=logfile
649 The 'debug=' value is generated using the following command
650 dmalloc -p log-stats -p log-non-free -p log-bad-space \
651 -p log-elapsed-time -p check-fence -p check-heap \
652 -p check-lists -p check-blank -p check-funcs -p realloc-copy \
655 Electric-fence support:
656 -----------------------
657 This enables compiling with Electric-fence support. Electric
658 fence is another very useful malloc debugging library which uses
659 your computer's virtual memory hardware to detect illegal memory
660 accesses. This support will make BusyBox be considerable larger
661 and run slower, so you should leave this option disabled unless
662 you are hunting a hard to find memory problem.
672 bool "Electric-fence"
676 source libbb/Config.in
682 source archival/Config.in
683 source coreutils/Config.in
684 source console-tools/Config.in
685 source debianutils/Config.in
686 source editors/Config.in
687 source findutils/Config.in
688 source init/Config.in
689 source loginutils/Config.in
690 source e2fsprogs/Config.in
691 source modutils/Config.in
692 source util-linux/Config.in
693 source miscutils/Config.in
694 source networking/Config.in
695 source printutils/Config.in
696 source mailutils/Config.in
697 source procps/Config.in
698 source runit/Config.in
699 source selinux/Config.in
700 source shell/Config.in
701 source sysklogd/Config.in