Shadow

For installation instructions see the Section called Installing Shadow-4.0.3 in Chapter 6.

Official Download Location

Shadow (4.0.3):
ftp://ftp.pld.org.pl/software/shadow/

Contents of Shadow

(Last checked against version 4.0.3.)

The Shadow package was created to strengthen the security of system passwords.

Shadow installs the following:

Program Files

chage, chfn, chpasswd, chsh, dpasswd, expiry, faillog, gpasswd, groupadd, groupdel, groupmod, groups, grpck, grpconv, grpunconv, lastlog, login, logoutd, mkpasswd, newgrp, newusers, passwd, pwck, pwconv, pwunconv, sg (link to newgrp), useradd, userdel, usermod, vigr (link to vipw) and vipw

Descriptions

(Last checked against version 4.0.3.)

Program file descriptions

chage is used to change the maximum number of days between obligatory password changes.

chfn is used to change a user's full name and some other info.

chpasswd is used to update the passwords of a whole series of user accounts in one go.

chsh is used to change a user's default login shell.

dpasswd is used to change dial-up passwords for user login shells.

expiry checks and enforces the current password expiration policy.

faillog is used to examine the log of login failures, to set a maximum number of failures before an account is blocked, or to reset the failure count.

gpasswd is used to add and delete members and administrators to groups.

groupadd creates a group with the given name.

groupdel deletes the group with the given name.

groupmod is used to modify the given group's name or GID.

groups reports the groups of which the given users are members.

grpck verifies the integrity of the group files, /etc/group and /etc/gshadow.

grpconv creates or updates the shadow group file from the normal group file.

grpunconv updates /etc/group from /etc/gshadow and then deletes the latter.

lastlog reports the most recent login of all users, or of a given user.

login is used by the system let users sign on.

logoutd is a daemon used to enforce restrictions on log-on time and ports.

mkpasswd encrypts the given password using the also given perturbation.

newgrp is used to change the current GID during a login session.

newusers is used to create or update a whole series of user accounts in one go.

passwd is used to change the password for a user or group account.

pwck verifies the integrity of the password files, /etc/passwd and /etc/shadow.

pwconv creates or updates the shadow password file from the normal password file.

pwunconv updates /etc/passwd from /etc/shadow and then deletes the latter.

sg executes a given command while the user's GID is set to that of the given group.

useradd creates a new user with the given name, or updates the default new-user information.

userdel deletes the given user account.

usermod is used to modify the given user's login name, UID, shell, initial group, home directory, and the like.

vigr can be used to edit the /etc/group or /etc/gshadow files.

vipw can be used to edit the /etc/passwd or /etc/shadow files.

Library file descriptions

libmisc...

libshadow contains functions used by most programs in this package.

Shadow Installation Dependencies

(Last checked against version 20001016.)

Bash: sh
Binutils: ar, as, ld, nm, ranlib
Coreutils: basename, cat, chmod, cp, echo, expr, install, ln, ls,
             mkdir, mv, rm, rmdir, sleep, sort, tr, uname, uniq
Diffutils: cmp
Gawk: gawk
GCC: cc1, collect2, cpp0, gcc
Gettext: msgfmt, xgettext
Glibc: ldconfig
Grep: egrep, grep
M4: m4
Make: make
Net-tools: hostname
Sed: sed
Texinfo: makeinfo