MAN page from OpenSuSE shadow-4.6-lp188.8.131.52.x86_64.rpm
Section: System Management Commands (8)
pwck - verify integrity of password files
- pwck [options] [passwd [ shadow ]]
DESCRIPTIONThepwckcommand verifies the integrity of the users and authentication information. It checks that all entries in/etc/passwdand/etc/shadowhave the proper format and contain valid data. The user is prompted to delete entries that are improperly formatted or which have other uncorrectable errors.
Checks are made to verify that each entry has:
- *the correct number of fields
- *a unique and valid user name
- *a valid user and group identifier
- *a valid primary group
- *a valid home directory
- *a valid login shell
shadowchecks are enabled when a second file parameter is specified or when/etc/shadowexists on the system.
These checks are the following:
- *every passwd entry has a matching shadow entry, and every shadow entry has a matching passwd entry
- *passwords are specified in the shadowed file
- *shadow entries have the correct number of fields
- *shadow entries are unique in shadow
- *the last password changes are not in the future
The checks for correct number of fields and unique user name are fatal. If the entry has the wrong number of fields, the user will be prompted to delete the entire line. If the user does not answer affirmatively, all further checks are bypassed. An entry with a duplicated user name is prompted for deletion, but the remaining checks will still be made. All other errors are warning and the user is encouraged to run theusermodcommand to correct the error.
The commands which operate on the/etc/passwdfile are not able to alter corrupted or duplicated entries.pwckshould be used in those circumstances to remove the offending entry.
The-rand-soptions cannot be combined.
The options which apply to thepwckcommand are:
- Display help message and exit.
- Report errors only. The warnings which do not require any action from the user won't be displayed.
- Execute thepwckcommand in read-only mode.
-R, --root CHROOT_DIR
- Apply changes in theCHROOT_DIRdirectory and use the configuration files from theCHROOT_DIRdirectory.
- Sort entries in/etc/passwdand/etc/shadowby UID.
By default,pwckoperates on the files/etc/passwdand/etc/shadow. The user may select alternate files with thepasswdandshadowparameters.
The following configuration variables in/etc/login.defschange the behavior of this tool:
- The maximum number of days a password may be used. If the password is older than this, a password change will be forced. If not specified, -1 will be assumed (which disables the restriction).
- The minimum number of days allowed between password changes. Any password changes attempted sooner than this will be rejected. If not specified, -1 will be assumed (which disables the restriction).
- The number of days warning given before a password expires. A zero means warning is given only upon the day of expiration, a negative value means no warning is given. If not specified, no warning will be provided.
- Group account information.
- User account information.
- Secure user account information.
Thepwckcommand exits with the following values:
- invalid command syntax
- one or more bad password entries
- can't open password files
- can't lock password files
- can't update password files
- can't sort password files
- EXIT VALUES
- SEE ALSO
This document was created byman2html,using the manual pages.