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#
# For a description of the syntax of this configuration file,
# see scripts/kbuild/config-language.txt.
#

menu "Login/Password Management Utilities"

config FEATURE_SHADOWPASSWDS
	bool "Support shadow passwords"
	default y
	help
	  Build support for shadow password in /etc/shadow. This file is only
	  readable by root and thus the encrypted passwords are no longer
	  publicly readable.

config USE_BB_PWD_GRP
	bool "Use internal password and group functions rather than system functions"
	default y
	help
	  If you leave this disabled, busybox will use the system's password
	  and group functions. And if you are using the GNU C library
	  (glibc), you will then need to install the /etc/nsswitch.conf
	  configuration file and the required /lib/libnss_* libraries in
	  order for the password and group functions to work. This generally
	  makes your embedded system quite a bit larger.

	  Enabling this option will cause busybox to directly access the
	  system's /etc/password, /etc/group files (and your system will be
	  smaller, and I will get fewer emails asking about how glibc NSS
	  works). When this option is enabled, you will not be able to use
	  PAM to access remote LDAP password servers and whatnot. And if you
	  want hostname resolution to work with glibc, you still need the
	  /lib/libnss_* libraries.

	  If you need to use glibc's nsswitch.conf mechanism
	  (e.g. if user/group database is NOT stored in /etc/passwd etc),
	  you must NOT use this option.

	  If you enable this option, it will add about 1.5k.

config USE_BB_SHADOW
	bool "Use internal shadow password functions"
	default y
	depends on USE_BB_PWD_GRP && FEATURE_SHADOWPASSWDS
	help
	  If you leave this disabled, busybox will use the system's shadow
	  password handling functions. And if you are using the GNU C library
	  (glibc), you will then need to install the /etc/nsswitch.conf
	  configuration file and the required /lib/libnss_* libraries in
	  order for the shadow password functions to work. This generally
	  makes your embedded system quite a bit larger.

	  Enabling this option will cause busybox to directly access the
	  system's /etc/shadow file when handling shadow passwords. This
	  makes your system smaller (and I will get fewer emails asking about
	  how glibc NSS works). When this option is enabled, you will not be
	  able to use PAM to access shadow passwords from remote LDAP
	  password servers and whatnot.

config USE_BB_CRYPT
	bool "Use internal crypt functions"
	default y
	help
	  Busybox has internal DES and MD5 crypt functions.
	  They produce results which are identical to corresponding
	  standard C library functions.

	  If you leave this disabled, busybox will use the system's
	  crypt functions. Most C libraries use large (~70k)
	  static buffers there, and also combine them with more general
	  DES encryption/decryption.

	  For busybox, having large static buffers is undesirable,
	  especially on NOMMU machines. Busybox also doesn't need
	  DES encryption/decryption and can do with smaller code.

	  If you enable this option, it will add about 4.8k of code
	  if you are building dynamically linked executable.
	  In static build, it makes code _smaller_ by about 1.2k,
	  and likely many kilobytes less of bss.

config USE_BB_CRYPT_SHA
	bool "Enable SHA256/512 crypt functions"
	default y
	depends on USE_BB_CRYPT
	help
	  Enable this if you have passwords starting with "$5$" or "$6$"
	  in your /etc/passwd or /etc/shadow files. These passwords
	  are hashed using SHA256 and SHA512 algorithms. Support for them
	  was added to glibc in 2008.
	  With this option off, login will fail password check for any
	  user which has password encrypted with these algorithms.

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