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 "Enable Linux-specific applets and features"
57 For the most part, busybox requires only POSIX compatibility
58 from the target system, but some applets and features use
59 Linux-specific interfaces.
61 Answering 'N' here will disable such applets and hide the
62 corresponding configuration options.
65 bool "Show applet usage messages"
68 Enabling this option, BusyBox applets will show terse help messages
69 when invoked with wrong arguments.
70 If you do not want to show any (helpful) usage message when
71 issuing wrong command syntax, you can say 'N' here,
72 saving approximately 7k.
74 config FEATURE_VERBOSE_USAGE
75 bool "Show verbose applet usage messages"
79 All BusyBox applets will show verbose help messages when
80 busybox is invoked with --help. This will add a lot of text to the
81 busybox binary. In the default configuration, this will add about
82 13k, but it can add much more depending on your configuration.
84 config FEATURE_COMPRESS_USAGE
85 bool "Store applet usage messages in compressed form"
89 Store usage messages in .bz compressed form, uncompress them
90 on-the-fly when <applet> --help is called.
92 If you have a really tiny busybox with few applets enabled (and
93 bunzip2 isn't one of them), the overhead of the decompressor might
94 be noticeable. Also, if you run executables directly from ROM
95 and have very little memory, this might not be a win. Otherwise,
96 you probably want this.
99 bool "Include busybox applet"
102 The busybox applet provides general help regarding busybox and
103 allows the included applets to be listed. It's also required
104 if applet links are to be installed at runtime.
106 If you can live without these features disabling this will save
109 config FEATURE_INSTALLER
110 bool "Support --install [-s] to install applet links at runtime"
114 Enable 'busybox --install [-s]' support. This will allow you to use
115 busybox at runtime to create hard links or symlinks for all the
116 applets that are compiled into busybox.
118 config INSTALL_NO_USR
119 bool "Don't use /usr"
122 Disable use of /usr. busybox --install and "make install"
123 will install applets only to /bin and /sbin,
124 never to /usr/bin or /usr/sbin.
127 bool "Support for PAM (Pluggable Authentication Modules)"
130 Use PAM in some busybox applets (currently login and httpd) instead
131 of direct access to password database.
134 bool "Support for --long-options"
137 Enable this if you want busybox applets to use the gnu --long-option
138 style, in addition to single character -a -b -c style options.
140 config FEATURE_DEVPTS
141 bool "Use the devpts filesystem for Unix98 PTYs"
144 Enable if you want BusyBox to use Unix98 PTY support. If enabled,
145 busybox will use /dev/ptmx for the master side of the pseudoterminal
146 and /dev/pts/<number> for the slave side. Otherwise, BSD style
147 /dev/ttyp<number> will be used. To use this option, you should have
150 config FEATURE_CLEAN_UP
151 bool "Clean up all memory before exiting (usually not needed)"
154 As a size optimization, busybox normally exits without explicitly
155 freeing dynamically allocated memory or closing files. This saves
156 space since the OS will clean up for us, but it can confuse debuggers
157 like valgrind, which report tons of memory and resource leaks.
159 Don't enable this unless you have a really good reason to clean
163 bool "Support utmp file"
166 The file /var/run/utmp is used to track who is currently logged in.
167 With this option on, certain applets (getty, login, telnetd etc)
168 will create and delete entries there.
169 "who" applet requires this option.
172 bool "Support wtmp file"
174 depends on FEATURE_UTMP
176 The file /var/run/wtmp is used to track when users have logged into
177 and logged out of the system.
178 With this option on, certain applets (getty, login, telnetd etc)
179 will append new entries there.
180 "last" applet requires this option.
182 config FEATURE_PIDFILE
183 bool "Support writing pidfiles"
186 This option makes some applets (e.g. crond, syslogd, inetd) write
187 a pidfile at the configured PID_FILE_PATH. It has no effect
188 on applets which require pidfiles to run.
191 string "Path to directory for pidfile"
193 depends on FEATURE_PIDFILE
195 This is the default path where pidfiles are created. Applets which
196 allow you to set the pidfile path on the command line will override
197 this value. The option has no effect on applets that require you to
198 specify a pidfile path.
201 bool "Support for SUID/SGID handling"
204 With this option you can install the busybox binary belonging
205 to root with the suid bit set, enabling some applets to perform
206 root-level operations even when run by ordinary users
207 (for example, mounting of user mounts in fstab needs this).
209 Busybox will automatically drop privileges for applets
210 that don't need root access.
212 If you are really paranoid and don't want to do this, build two
213 busybox binaries with different applets in them (and the appropriate
214 symlinks pointing to each binary), and only set the suid bit on the
217 The applets which require root rights (need suid bit or
218 to be run by root) and will refuse to execute otherwise:
219 crontab, login, passwd, su, vlock, wall.
221 The applets which will use root rights if they have them
222 (via suid bit, or because run by root), but would try to work
223 without root right nevertheless:
224 findfs, ping[6], traceroute[6], mount.
226 Note that if you DONT select this option, but DO make busybox
227 suid root, ALL applets will run under root, which is a huge
228 security hole (think "cp /some/file /etc/passwd").
230 config FEATURE_SUID_CONFIG
231 bool "Runtime SUID/SGID configuration via /etc/busybox.conf"
233 depends on FEATURE_SUID
235 Allow the SUID / SGID state of an applet to be determined at runtime
236 by checking /etc/busybox.conf. (This is sort of a poor man's sudo.)
237 The format of this file is as follows:
239 APPLET = [Ssx-][Ssx-][x-] [USER.GROUP]
241 s: USER or GROUP is allowed to execute APPLET.
242 APPLET will run under USER or GROUP
243 (reagardless of who's running it).
244 S: USER or GROUP is NOT allowed to execute APPLET.
245 APPLET will run under USER or GROUP.
246 This option is not very sensical.
247 x: USER/GROUP/others are allowed to execute APPLET.
248 No UID/GID change will be done when it is run.
249 -: USER/GROUP/others are not allowed to execute APPLET.
251 An example might help:
254 su = ssx root.0 # applet su can be run by anyone and runs with
256 su = ssx # exactly the same
258 mount = sx- root.disk # applet mount can be run by root and members
259 # of group disk (but not anyone else)
260 # and runs with euid=0 (egid is not changed)
262 cp = --- # disable applet cp for everyone
264 The file has to be owned by user root, group root and has to be
265 writeable only by root:
266 (chown 0.0 /etc/busybox.conf; chmod 600 /etc/busybox.conf)
267 The busybox executable has to be owned by user root, group
268 root and has to be setuid root for this to work:
269 (chown 0.0 /bin/busybox; chmod 4755 /bin/busybox)
271 Robert 'sandman' Griebl has more information here:
272 <url: http://www.softforge.de/bb/suid.html >.
274 config FEATURE_SUID_CONFIG_QUIET
275 bool "Suppress warning message if /etc/busybox.conf is not readable"
277 depends on FEATURE_SUID_CONFIG
279 /etc/busybox.conf should be readable by the user needing the SUID,
280 check this option to avoid users to be notified about missing
284 bool "Support NSA Security Enhanced Linux"
286 select PLATFORM_LINUX
288 Enable support for SELinux in applets ls, ps, and id. Also provide
289 the option of compiling in SELinux applets.
291 If you do not have a complete SELinux userland installed, this stuff
292 will not compile. Specifially, libselinux 1.28 or better is
293 directly required by busybox. If the installation is located in a
294 non-standard directory, provide it by invoking make as follows:
295 CFLAGS=-I<libselinux-include-path> \
296 LDFLAGS=-L<libselinux-lib-path> \
299 Most people will leave this set to 'N'.
301 config FEATURE_PREFER_APPLETS
302 bool "exec prefers applets"
305 This is an experimental option which directs applets about to
306 call 'exec' to try and find an applicable busybox applet before
307 searching the PATH. This is typically done by exec'ing
309 This may affect shell, find -exec, xargs and similar applets.
310 They will use applets even if /bin/<applet> -> busybox link
311 is missing (or is not a link to busybox). However, this causes
312 problems in chroot jails without mounted /proc and with ps/top
313 (command name can be shown as 'exe' for applets started this way).
315 config BUSYBOX_EXEC_PATH
316 string "Path to BusyBox executable"
317 default "/proc/self/exe"
319 When Busybox applets need to run other busybox applets, BusyBox
320 sometimes needs to exec() itself. When the /proc filesystem is
321 mounted, /proc/self/exe always points to the currently running
322 executable. If you haven't got /proc, set this to wherever you
323 want to run BusyBox from.
325 # These are auto-selected by other options
327 config FEATURE_SYSLOG
328 bool #No description makes it a hidden option
331 # This option is auto-selected when you select any applet which may
332 # send its output to syslog. You do not need to select it manually.
334 config FEATURE_HAVE_RPC
335 bool #No description makes it a hidden option
338 # This is automatically selected if any of enabled applets need it.
339 # 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 tiny
390 separate executable. Enabling it for "one big busybox binary"
391 approach serves no purpose and increases code size.
392 You should almost certainly say "no" to this.
394 ### config FEATURE_FULL_LIBBUSYBOX
395 ### bool "Feature-complete libbusybox"
396 ### default n if !FEATURE_SHARED_BUSYBOX
397 ### depends on BUILD_LIBBUSYBOX
399 ### Build a libbusybox with the complete feature-set, disregarding
400 ### the actually selected config.
402 ### Normally, libbusybox will only contain the features which are
403 ### used by busybox itself. If you plan to write a separate
404 ### standalone application which uses libbusybox say 'Y'.
406 ### Note: libbusybox is GPL, not LGPL, and exports no stable API that
407 ### might act as a copyright barrier. We can and will modify the
408 ### exported function set between releases (even minor version number
409 ### changes), and happily break out-of-tree features.
411 ### Say 'N' if in doubt.
413 config FEATURE_INDIVIDUAL
414 bool "Produce a binary for each applet, linked against libbusybox"
416 depends on BUILD_LIBBUSYBOX
418 If your CPU architecture doesn't allow for sharing text/rodata
419 sections of running binaries, but allows for runtime dynamic
420 libraries, this option will allow you to reduce memory footprint
421 when you have many different applets running at once.
423 If your CPU architecture allows for sharing text/rodata,
424 having single binary is more optimal.
426 Each applet will be a tiny program, dynamically linked
427 against libbusybox.so.N.N.N.
429 You need to have a working dynamic linker.
431 config FEATURE_SHARED_BUSYBOX
432 bool "Produce additional busybox binary linked against libbusybox"
434 depends on BUILD_LIBBUSYBOX
436 Build busybox, dynamically linked against libbusybox.so.N.N.N.
438 You need to have a working dynamic linker.
440 ### config BUILD_AT_ONCE
441 ### bool "Compile all sources at once"
444 ### Normally each source-file is compiled with one invocation of
446 ### If you set this option, all sources are compiled at once.
447 ### This gives the compiler more opportunities to optimize which can
448 ### result in smaller and/or faster binaries.
450 ### Setting this option will consume alot of memory, e.g. if you
451 ### enable all applets with all features, gcc uses more than 300MB
452 ### RAM during compilation of busybox.
454 ### This option is most likely only beneficial for newer compilers
455 ### such as gcc-4.1 and above.
457 ### Say 'N' unless you know what you are doing.
460 bool "Build with Large File Support (for accessing files > 2 GB)"
463 If you want to build BusyBox with large file support, then enable
464 this option. This will have no effect if your kernel or your C
465 library lacks large file support for large files. Some of the
466 programs that can benefit from large file support include dd, gzip,
467 cp, mount, tar, and many others. If you want to access files larger
468 than 2 Gigabytes, enable this option. Otherwise, leave it set to 'N'.
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 If you aren't developing/testing busybox, say N here.
617 bool "Build unit tests"
620 Say Y here if you want to build unit tests (both the framework and
621 test cases) as a Busybox applet. This results in bigger code, so you
622 probably don't want this option in production builds.
625 bool "Abort compilation on any warning"
628 Selecting this will add -Werror to gcc command line.
630 Most people should answer N.
633 prompt "Additional debugging library"
636 Using an additional debugging library will make BusyBox become
637 considerable larger and will cause it to run more slowly. You
638 should always leave this option disabled for production use.
642 This enables compiling with dmalloc ( http://dmalloc.com/ )
643 which is an excellent public domain mem leak and malloc problem
644 detector. To enable dmalloc, before running busybox you will
645 want to properly set your environment, for example:
646 export DMALLOC_OPTIONS=debug=0x34f47d83,inter=100,log=logfile
647 The 'debug=' value is generated using the following command
648 dmalloc -p log-stats -p log-non-free -p log-bad-space \
649 -p log-elapsed-time -p check-fence -p check-heap \
650 -p check-lists -p check-blank -p check-funcs -p realloc-copy \
653 Electric-fence support:
654 -----------------------
655 This enables compiling with Electric-fence support. Electric
656 fence is another very useful malloc debugging library which uses
657 your computer's virtual memory hardware to detect illegal memory
658 accesses. This support will make BusyBox be considerable larger
659 and run slower, so you should leave this option disabled unless
660 you are hunting a hard to find memory problem.
670 bool "Electric-fence"
676 source libbb/Config.in
680 source archival/Config.in
681 source coreutils/Config.in
682 source console-tools/Config.in
683 source debianutils/Config.in
684 source editors/Config.in
685 source findutils/Config.in
686 source init/Config.in
687 source loginutils/Config.in
688 source e2fsprogs/Config.in
689 source modutils/Config.in
690 source util-linux/Config.in
691 source miscutils/Config.in
692 source networking/Config.in
693 source printutils/Config.in
694 source mailutils/Config.in
695 source procps/Config.in
696 source runit/Config.in
697 source selinux/Config.in
698 source shell/Config.in
699 source sysklogd/Config.in