2 # For a description of the syntax of this configuration file,
3 # see scripts/kbuild/config-language.txt.
6 mainmenu "Configuration"
15 bool "Enable compatibility for full-blown desktop systems"
18 Enable applet options and features which are not essential.
19 Many applet options have dedicated config options to (de)select them
20 under that applet; this options enables those options which have no
21 individual config item for them.
23 Select this if you plan to use busybox on full-blown desktop machine
24 with common Linux distro, which needs higher level of command-line
27 If you are preparing your build to be used on an embedded box
28 where you have tighter control over the entire set of userspace
29 tools, you can unselect this option for smaller code size.
32 bool "Provide compatible behavior for rare corner cases (bigger code)"
35 This option makes grep, sed etc handle rare corner cases
36 (embedded NUL bytes and such). This makes code bigger and uses
37 some GNU extensions in libc. You probably only need this option
38 if you plan to run busybox on desktop.
41 bool "Enable obsolete features removed before SUSv3"
44 This option will enable backwards compatibility with SuSv2,
45 specifically, old-style numeric options ('command -1 <file>')
46 will be supported in head, tail, and fold. (Note: should
50 bool "Support --long-options"
53 Enable this if you want busybox applets to use the gnu --long-option
54 style, in addition to single character -a -b -c style options.
57 bool "Show applet usage messages"
60 Enabling this option, applets will show terse help messages
61 when invoked with wrong arguments.
62 If you do not want to show any (helpful) usage message when
63 issuing wrong command syntax, you can say 'N' here,
64 saving approximately 7k.
66 config FEATURE_VERBOSE_USAGE
67 bool "Show verbose applet usage messages"
71 All applets will show verbose help messages when invoked with --help.
72 This will add a lot of text to the binary.
74 config FEATURE_COMPRESS_USAGE
75 bool "Store applet usage messages in compressed form"
79 Store usage messages in .bz2 compressed form, uncompress them
80 on-the-fly when "APPLET --help" is run.
82 If you have a really tiny busybox with few applets enabled (and
83 bunzip2 isn't one of them), the overhead of the decompressor might
84 be noticeable. Also, if you run executables directly from ROM
85 and have very little memory, this might not be a win. Otherwise,
86 you probably want this.
89 bool "Support files > 2 GB"
92 If you need to work with large files, enable this option.
93 This will have no effect if your kernel or your C
94 library lacks large file support for large files. Some of the
95 programs that can benefit from large file support include dd, gzip,
99 bool "Support PAM (Pluggable Authentication Modules)"
102 Use PAM in some applets (currently login and httpd) instead
103 of direct access to password database.
105 config FEATURE_DEVPTS
106 bool "Use the devpts filesystem for Unix98 PTYs"
109 Enable if you want to use Unix98 PTY support. If enabled,
110 busybox will use /dev/ptmx for the master side of the pseudoterminal
111 and /dev/pts/<number> for the slave side. Otherwise, BSD style
112 /dev/ttyp<number> will be used. To use this option, you should have
116 bool "Support utmp file"
119 The file /var/run/utmp is used to track who is currently logged in.
120 With this option on, certain applets (getty, login, telnetd etc)
121 will create and delete entries there.
122 "who" applet requires this option.
125 bool "Support wtmp file"
127 depends on FEATURE_UTMP
129 The file /var/run/wtmp is used to track when users have logged into
130 and logged out of the system.
131 With this option on, certain applets (getty, login, telnetd etc)
132 will append new entries there.
133 "last" applet requires this option.
135 config FEATURE_PIDFILE
136 bool "Support writing pidfiles"
139 This option makes some applets (e.g. crond, syslogd, inetd) write
140 a pidfile at the configured PID_FILE_PATH. It has no effect
141 on applets which require pidfiles to run.
144 string "Directory for pidfiles"
146 depends on FEATURE_PIDFILE
148 This is the default path where pidfiles are created. Applets which
149 allow you to set the pidfile path on the command line will override
150 this value. The option has no effect on applets that require you to
151 specify a pidfile path.
154 bool "Include busybox applet"
157 The busybox applet provides general help message and allows
158 the included applets to be listed. It also provides
159 optional --install command to create applet links. If you unselect
160 this option, running busybox without any arguments will give
161 just a cryptic error message:
164 busybox: applet not found
166 Running "busybox APPLET [ARGS...]" will still work, of course.
168 config FEATURE_INSTALLER
169 bool "Support --install [-s] to install applet links at runtime"
173 Enable 'busybox --install [-s]' support. This will allow you to use
174 busybox at runtime to create hard links or symlinks for all the
175 applets that are compiled into busybox.
177 config INSTALL_NO_USR
178 bool "Don't use /usr"
181 Disable use of /usr. "busybox --install" and "make install"
182 will install applets only to /bin and /sbin,
183 never to /usr/bin or /usr/sbin.
186 bool "Drop SUID state for most applets"
189 With this option you can install the busybox binary belonging
190 to root with the suid bit set, enabling some applets to perform
191 root-level operations even when run by ordinary users
192 (for example, mounting of user mounts in fstab needs this).
194 With this option enabled, busybox drops privileges for applets
195 that don't need root access, before entering their main() function.
197 If you are really paranoid and don't want even initial busybox code
198 to run under root for every applet, build two busybox binaries with
199 different applets in them (and the appropriate symlinks pointing
200 to each binary), and only set the suid bit on the one that needs it.
202 Some applets which require root rights (need suid bit on the binary
203 or to be run by root) and will refuse to execute otherwise:
204 crontab, login, passwd, su, vlock, wall.
206 The applets which will use root rights if they have them
207 (via suid bit, or because run by root), but would try to work
208 without root right nevertheless:
209 findfs, ping[6], traceroute[6], mount.
211 Note that if you DO NOT select this option, but DO make busybox
212 suid root, ALL applets will run under root, which is a huge
213 security hole (think "cp /some/file /etc/passwd").
215 config FEATURE_SUID_CONFIG
216 bool "Enable SUID configuration via /etc/busybox.conf"
218 depends on FEATURE_SUID
220 Allow the SUID/SGID state of an applet to be determined at runtime
221 by checking /etc/busybox.conf. (This is sort of a poor man's sudo.)
222 The format of this file is as follows:
224 APPLET = [Ssx-][Ssx-][x-] [USER.GROUP]
226 s: USER or GROUP is allowed to execute APPLET.
227 APPLET will run under USER or GROUP
228 (regardless of who's running it).
229 S: USER or GROUP is NOT allowed to execute APPLET.
230 APPLET will run under USER or GROUP.
231 This option is not very sensical.
232 x: USER/GROUP/others are allowed to execute APPLET.
233 No UID/GID change will be done when it is run.
234 -: USER/GROUP/others are not allowed to execute APPLET.
236 An example might help:
239 |su = ssx root.0 # applet su can be run by anyone and runs with
241 |su = ssx # exactly the same
243 |mount = sx- root.disk # applet mount can be run by root and members
244 | # of group disk (but not anyone else)
245 | # and runs with euid=0 (egid is not changed)
247 |cp = --- # disable applet cp for everyone
249 The file has to be owned by user root, group root and has to be
250 writeable only by root:
251 (chown 0.0 /etc/busybox.conf; chmod 600 /etc/busybox.conf)
252 The busybox executable has to be owned by user root, group
253 root and has to be setuid root for this to work:
254 (chown 0.0 /bin/busybox; chmod 4755 /bin/busybox)
256 Robert 'sandman' Griebl has more information here:
257 <url: http://www.softforge.de/bb/suid.html >.
259 config FEATURE_SUID_CONFIG_QUIET
260 bool "Suppress warning message if /etc/busybox.conf is not readable"
262 depends on FEATURE_SUID_CONFIG
264 /etc/busybox.conf should be readable by the user needing the SUID,
265 check this option to avoid users to be notified about missing
268 config FEATURE_PREFER_APPLETS
269 bool "exec prefers applets"
272 This is an experimental option which directs applets about to
273 call 'exec' to try and find an applicable busybox applet before
274 searching the PATH. This is typically done by exec'ing
277 This may affect shell, find -exec, xargs and similar applets.
278 They will use applets even if /bin/APPLET -> busybox link
279 is missing (or is not a link to busybox). However, this causes
280 problems in chroot jails without mounted /proc and with ps/top
281 (command name can be shown as 'exe' for applets started this way).
283 config BUSYBOX_EXEC_PATH
284 string "Path to busybox executable"
285 default "/proc/self/exe"
287 When applets need to run other applets, busybox
288 sometimes needs to exec() itself. When the /proc filesystem is
289 mounted, /proc/self/exe always points to the currently running
290 executable. If you haven't got /proc, set this to wherever you
291 want to run busybox from.
294 bool "Support NSA Security Enhanced Linux"
296 select PLATFORM_LINUX
298 Enable support for SELinux in applets ls, ps, and id. Also provide
299 the option of compiling in SELinux applets.
301 If you do not have a complete SELinux userland installed, this stuff
302 will not compile. Specifially, libselinux 1.28 or better is
303 directly required by busybox. If the installation is located in a
304 non-standard directory, provide it by invoking make as follows:
306 CFLAGS=-I<libselinux-include-path> \
307 LDFLAGS=-L<libselinux-lib-path> \
310 Most people will leave this set to 'N'.
312 config FEATURE_CLEAN_UP
313 bool "Clean up all memory before exiting (usually not needed)"
316 As a size optimization, busybox normally exits without explicitly
317 freeing dynamically allocated memory or closing files. This saves
318 space since the OS will clean up for us, but it can confuse debuggers
319 like valgrind, which report tons of memory and resource leaks.
321 Don't enable this unless you have a really good reason to clean
324 # These are auto-selected by other options
326 config FEATURE_SYSLOG
327 bool #No description makes it a hidden option
330 #This option is auto-selected when you select any applet which may
331 #send its output to syslog. You do not need to select it manually.
333 config FEATURE_HAVE_RPC
334 bool #No description makes it a hidden option
337 #This is automatically selected if any of enabled applets need it.
338 #You do not need to select it manually.
340 config PLATFORM_LINUX
341 bool #No description makes it a hidden option
344 #For the most part, busybox requires only POSIX compatibility
345 #from the target system, but some applets and features use
346 #Linux-specific interfaces.
348 #This is automatically selected if any applet or feature requires
349 #Linux-specific interfaces. You do not need to select it manually.
351 comment 'Build Options'
354 bool "Build static binary (no shared libs)"
357 If you want to build a static binary, which does not use
358 or require any shared libraries, enable this option.
359 Static binaries are larger, but do not require functioning
360 dynamic libraries to be present, which is important if used
361 as a system rescue tool.
364 bool "Build position independent executable"
368 Hardened code option. PIE binaries are loaded at a different
369 address at each invocation. This has some overhead,
370 particularly on x86-32 which is short on registers.
372 Most people will leave this set to 'N'.
375 bool "Force NOMMU build"
378 Busybox tries to detect whether architecture it is being
379 built against supports MMU or not. If this detection fails,
380 or if you want to build NOMMU version of busybox for testing,
381 you may force NOMMU build here.
383 Most people will leave this set to 'N'.
385 # PIE can be made to work with BUILD_LIBBUSYBOX, but currently
386 # build system does not support that
387 config BUILD_LIBBUSYBOX
388 bool "Build shared libbusybox"
390 depends on !FEATURE_PREFER_APPLETS && !PIE && !STATIC
392 Build a shared library libbusybox.so.N.N.N which contains all
395 This feature allows every applet to be built as a really tiny
396 separate executable linked against the library:
398 | text data bss dec hex filename
399 | 939 212 28 1179 49b 0_lib/last
400 | 939 212 28 1179 49b 0_lib/less
401 | 919138 8328 1556 929022 e2cfe 0_lib/libbusybox.so.1.N.M
403 This is useful on NOMMU systems which are not capable
404 of sharing executables, but are capable of sharing code
405 in dynamic libraries.
407 config FEATURE_LIBBUSYBOX_STATIC
408 bool "Pull in all external references into libbusybox"
410 depends on BUILD_LIBBUSYBOX
412 Make libbusybox library independent, not using or requiring
413 any other shared libraries.
415 config FEATURE_INDIVIDUAL
416 bool "Produce a binary for each applet, linked against libbusybox"
418 depends on BUILD_LIBBUSYBOX
420 If your CPU architecture doesn't allow for sharing text/rodata
421 sections of running binaries, but allows for runtime dynamic
422 libraries, this option will allow you to reduce memory footprint
423 when you have many different applets running at once.
425 If your CPU architecture allows for sharing text/rodata,
426 having single binary is more optimal.
428 Each applet will be a tiny program, dynamically linked
429 against libbusybox.so.N.N.N.
431 You need to have a working dynamic linker.
433 config FEATURE_SHARED_BUSYBOX
434 bool "Produce additional busybox binary linked against libbusybox"
436 depends on BUILD_LIBBUSYBOX
438 Build busybox, dynamically linked against libbusybox.so.N.N.N.
440 You need to have a working dynamic linker.
442 ### config BUILD_AT_ONCE
443 ### bool "Compile all sources at once"
446 ### Normally each source-file is compiled with one invocation of
448 ### If you set this option, all sources are compiled at once.
449 ### This gives the compiler more opportunities to optimize which can
450 ### result in smaller and/or faster binaries.
452 ### Setting this option will consume alot of memory, e.g. if you
453 ### enable all applets with all features, gcc uses more than 300MB
454 ### RAM during compilation of busybox.
456 ### This option is most likely only beneficial for newer compilers
457 ### such as gcc-4.1 and above.
459 ### Say 'N' unless you know what you are doing.
461 config CROSS_COMPILER_PREFIX
462 string "Cross compiler prefix"
465 If you want to build busybox with a cross compiler, then you
466 will need to set this to the cross-compiler prefix, for example,
469 Note that CROSS_COMPILE environment variable or
470 "make CROSS_COMPILE=xxx ..." will override this selection.
472 Native builds leave this empty.
475 string "Path to sysroot"
478 If you want to build busybox with a cross compiler, then you
479 might also need to specify where /usr/include and /usr/lib
482 For example, busybox can be built against an installed
483 Android NDK, platform version 9, for ARM ABI with
485 CONFIG_SYSROOT=/opt/android-ndk/platforms/android-9/arch-arm
487 Native builds leave this empty.
490 string "Additional CFLAGS"
493 Additional CFLAGS to pass to the compiler verbatim.
496 string "Additional LDFLAGS"
499 Additional LDFLAGS to pass to the linker verbatim.
502 string "Additional LDLIBS"
505 Additional LDLIBS to pass to the linker with -l.
507 config USE_PORTABLE_CODE
508 bool "Avoid using GCC-specific code constructs"
511 Use this option if you are trying to compile busybox with
512 compiler other than gcc.
513 If you do use gcc, this option may needlessly increase code size.
515 comment 'Installation Options ("make install" behavior)'
518 prompt "What kind of applet links to install"
519 default INSTALL_APPLET_SYMLINKS
521 Choose what kind of links to applets are created by "make install".
523 config INSTALL_APPLET_SYMLINKS
526 Install applets as soft-links to the busybox binary. This needs some
527 free inodes on the filesystem, but might help with filesystem
528 generators that can't cope with hard-links.
530 config INSTALL_APPLET_HARDLINKS
533 Install applets as hard-links to the busybox binary. This might
534 count on a filesystem with few inodes.
536 config INSTALL_APPLET_SCRIPT_WRAPPERS
537 bool "as script wrappers"
539 Install applets as script wrappers that call the busybox binary.
541 config INSTALL_APPLET_DONT
544 Do not install applet links. Useful when you plan to use
545 busybox --install for installing links, or plan to use
546 a standalone shell and thus don't need applet links.
551 prompt "/bin/sh applet link"
552 default INSTALL_SH_APPLET_SYMLINK
553 depends on INSTALL_APPLET_SCRIPT_WRAPPERS
555 Choose how you install /bin/sh applet link.
557 config INSTALL_SH_APPLET_SYMLINK
560 Install /bin/sh applet as soft-link to the busybox binary.
562 config INSTALL_SH_APPLET_HARDLINK
565 Install /bin/sh applet as hard-link to the busybox binary.
567 config INSTALL_SH_APPLET_SCRIPT_WRAPPER
568 bool "as script wrapper"
570 Install /bin/sh applet as script wrapper that calls
576 string "Destination path for 'make install'"
579 Where "make install" should install busybox binary and links.
581 comment 'Debugging Options'
584 bool "Build with debug information"
587 Say Y here to compile with debug information.
588 This increases the size of the binary considerably, and
589 should only be used when doing development.
591 This adds -g option to gcc command line.
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 This replaces -Os/-O2 with -O0 in gcc command line.
608 config DEBUG_SANITIZE
609 bool "Enable runtime sanitizers (ASAN/LSAN/USAN/etc...)"
612 Say Y here if you want to enable runtime sanitizers. These help
613 catch bad memory accesses (e.g. buffer overflows), but will make
614 the executable larger and slow down runtime a bit.
616 This adds -fsanitize=foo options to gcc command line.
618 If you aren't developing/testing busybox, say N here.
621 bool "Build unit tests"
624 Say Y here if you want to build unit tests (both the framework and
625 test cases) as an applet. This results in bigger code, so you
626 probably don't want this option in production builds.
629 bool "Abort compilation on any warning"
632 This adds -Werror to gcc command line.
634 Most people should answer N.
637 prompt "Additional debugging library"
640 Using an additional debugging library will make busybox become
641 considerably larger and will cause it to run more slowly. You
642 should always leave this option disabled for production use.
646 This enables compiling with dmalloc ( http://dmalloc.com/ )
647 which is an excellent public domain mem leak and malloc problem
648 detector. To enable dmalloc, before running busybox you will
649 want to properly set your environment, for example:
650 export DMALLOC_OPTIONS=debug=0x34f47d83,inter=100,log=logfile
651 The 'debug=' value is generated using the following command
652 dmalloc -p log-stats -p log-non-free -p log-bad-space \
653 -p log-elapsed-time -p check-fence -p check-heap \
654 -p check-lists -p check-blank -p check-funcs -p realloc-copy \
657 Electric-fence support:
658 -----------------------
659 This enables compiling with Electric-fence support. Electric
660 fence is another very useful malloc debugging library which uses
661 your computer's virtual memory hardware to detect illegal memory
662 accesses. This support will make busybox be considerably larger
663 and run slower, so you should leave this option disabled unless
664 you are hunting a hard to find memory problem.
674 bool "Electric-fence"
678 source libbb/Config.in
684 source archival/Config.in
685 source coreutils/Config.in
686 source console-tools/Config.in
687 source debianutils/Config.in
688 source editors/Config.in
689 source findutils/Config.in
690 source init/Config.in
691 source loginutils/Config.in
692 source e2fsprogs/Config.in
693 source modutils/Config.in
694 source util-linux/Config.in
695 source miscutils/Config.in
696 source networking/Config.in
697 source printutils/Config.in
698 source mailutils/Config.in
699 source procps/Config.in
700 source runit/Config.in
701 source selinux/Config.in
702 source shell/Config.in
703 source sysklogd/Config.in