shadow
5
shadow
encrypted password file
DESCRIPTION
shadow contains the encrypted
password information for user's accounts
and optional the password aging information. Included is
Login name
Encrypted password
Days since Jan 1, 1970 that password was last changed
Days before password may be changed
Days after which password must be changed
Days before password is to expire that user is warned
Days after password expires that account is disabled
Days since Jan 1, 1970 that account is disabled
A reserved field
The password field must be filled. The encryped password consists
of 13 to 24 characters from the 64 characters alphabet a thru z, A
thru Z, 0 thru 9, \. and /. Optionally it can start with a "$"
character. This means the encrypted password was generated using
another (not DES) algorithm. For example if it starts with "$1$" it
means the MD5-based algorithm was used.
Refer to
crypt3
for details on how this string is interpreted.
The date of the last password change is given as the number of
days since Jan 1, 1970. The password may not be changed again until
the proper number of days have passed, and must be changed after the
maximum number of days. If the minimum number of days required is
greater than the maximum number of day allowed, this password may not
be changed by the user.
An account is considered to be inactive and is disabled if the
password is not changed within the specified number of days after the
password expires. An account will also be disabled on the specified
day regardless of other password expiration information.
This information supercedes any password or password age
information present in /etc/passwd.
This file must not be readable by regular users if password
security is to be maintained.
FILES
/etc/passwd
user account information
/etc/shadow
secure user account information
SEE ALSO
chage1
,
login1
,
passwd1
,
su1
,
passwd5
,
pwconv8
,
pwunconv8
,
sulogin8
AUTHOR
Julianne Frances Haugh (jockgrrl@ix.netcom.com)