PASSWD(1) (Essential Utilities) PASSWD(1)
NAME
passwd - change login password and password attributes
SYNOPSIS
passwd [ name ]
passwd [ -l | -d ] [ -n min ] [ -f ] [ -x max ] name
passwd -s [ -a ]
passwd -s [ name ]
DESCRIPTION
The passwd command changes the password or lists password
attributes associated with the user's login name.
Additionally, super-users may use passwd to install or
change passwords and attributes associated with any login
name.
When used to change a password, passwd prompts ordinary
users for their old password, if any. It then prompts for
the new password twice. When the old password is entered,
passwd checks to see if it has "aged" sufficiently. If
"aging" is insufficient, passwd terminates; see passwd(4).
Assuming aging is sufficient, a check is made to ensure that
the new password meets construction requirements. When the
new password is entered a second time, the two copies of the
new password are compared. If the two copies are not
identical the cycle of prompting for the new password is
repeated for at most two more times.
Passwords must be constructed to meet the following
requirements:
Each password must have at least six characters. Only
the first eight characters are significant.
Each password must contain at least two alphabetic
characters and at least one numeric or special
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PASSWD(1) (Essential Utilities) PASSWD(1)
character. In this case, "alphabetic" refers to all
upper or lower case letters.
Each password must differ from the user's login name
and any reverse or circular shift of that login name.
For comparison purposes, an upper case letter and its
corresponding lower case letter are equivalent.
New passwords must differ from the old by at least
three characters. For comparison purposes, an upper
case letter and its corresponding lower case letter are
equivalent.
Super-users (e.g., real and effective uid equal to zero, see
id(1M) and su(1M)) may change any password; hence, passwd
does not prompt super-users for the old password. Super-
users are not forced to comply with password aging and
password construction requirements. A super-user can create
a null password by entering a carriage return in response to
the prompt for a new password. (This differs from passwd -d
because the "password" prompt will still be displayed.)
Any user may use the -s option to show password attributes
for his or her own login name.
The format of the display will be:
name status mm/dd/yy min max
or, if password aging information is not present,
name status
where
name The login ID of the user.
status The password status of name: "PS" stands for
passworded or locked, "LK" stands for locked,
and "NP" stands for no password.
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PASSWD(1) (Essential Utilities) PASSWD(1)
mm/dd/yy The date password was last changed for name.
(Note that all password aging dates are
determined using Greenwich Mean Time and,
therefore, may differ by as much as a day in
other time zones.)
min The minimum number of days required between
password changes for name.
max The maximum number of days the password is valid
for name.
Only a super-user can use the following options:
-l Locks password entry for name.
-d Deletes password for name. The login name will
not be prompted for password.
-n Set minimum field for name. The min field
contains the minimum number of days between
password changes for name. If min is greater than
max, the user may not change the password. Always
use this option with the -x option, unless max is
set to -1 (aging turned off). In that case, min
need not be set.
-x Set maximum field for name. The max field
contains the number of days that the password is
valid for name. The aging for name will be turned
off immediately if max is set to -1. If it is set
to 0, then the user is forced to change the
password at the next login session and aging is
turned off.
-a Show password attributes for all entries. Use
only with -s option; name must not be provided.
-f Force the user to change password at the next
login by expiring the password for name.
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PASSWD(1) (Essential Utilities) PASSWD(1)
FILES
/etc/passwd, /etc/shadow, /etc/opasswd, /etc/oshadow
SEE ALSO
login(1).
crypt(3C), passwd(4) in the Programmer's Reference Manual.
id(1M), passmgmt(1M), pwconv(1M), su(1M), in the System
Administrator's Reference Manual.
WARNING
If the optional /etc/shadow file feature is used, the
passwd(1) command will use that, instead of the /etc/passwd
file, to obtain password information. Since the way
password aging information is stored in the two files is
slightly different, the output from passwd options that use
this information may also be different.
DIAGNOSTICS
The passwd command exits with one of the following values:
0 SUCCESS.
1 Permission denied.
2 Invalid combination of options.
3 Unexpected failure. Password file unchanged.
4 Unexpected failure. Password file(s) missing.
5 Password file(s) busy. Try again later.
6 Invalid argument to option.
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