- 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.
+ 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 BUSYBOX_CONFIG_USE_BB_CRYPT
+ bool "Use internal crypt functions"
+ default n
+ 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 BUSYBOX_CONFIG_USE_BB_CRYPT_SHA
+ bool "Enable SHA256/512 crypt functions"
+ default n
+ depends on BUSYBOX_CONFIG_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.