PASSWD(1) General Commands Manual PASSWD(1)
passwd - modify a user's password
passwd changes the user's password. If no user is specified, the user's
login name is used (see logname(1)). First, the user is prompted for
their current password. If the current password is correctly typed, a
new password is requested. The new password must be entered twice to
avoid typing errors.
The new password should be at least six characters long and not purely
alphabetic. Its total length must be less than _PASSWORD_LEN (currently
128 characters). A mixture of both lower and uppercase letters, numbers,
and meta-characters is encouraged.
The quality of the password can be enforced by specifying an external
checking program via the "passwordcheck" variable in login.conf(5).
The superuser is not required to provide a user's current password if
only the local password is modified.
Password encryption parameters depend on the configuration of the
"localcipher" capability in login.conf(5). If none is specified then
blowfish is used, with the number of rounds selected based on system
/etc/login.conf configuration options
/etc/master.passwd user database
/etc/passwd user database, with confidential information removed
/etc/passwd.XXXXXX temporary copy of the password file
/etc/ptmp lock file for the passwd database
Attempting to lock password file, please wait or press ^C to abort
The password file is currently locked by another process; passwd will
keep trying to lock the password file until it succeeds or you hit the
interrupt character (control-C by default). If passwd is interrupted
while trying to gain the lock the password change will be lost.
If the process holding the lock was prematurely terminated the lock file
may be stale and passwd will wait forever trying to lock the password
file. To determine whether a live process is actually holding the lock,
the admin may run the following:
$ fstat /etc/ptmp
If no process is listed, it is safe to remove the /etc/ptmp file to clear
chpass(1), encrypt(1), logname(1), login.conf(5), passwd(5), pwd_mkdb(8),
Robert Morris and Ken Thompson, "Password security: a case history",
Communications of the ACM, Issue 11, Volume 22, 594-597, Nov. 1979.
A passwd command appeared in Version 3 AT&T UNIX.
OpenBSD 6.4 August 19, 2016 OpenBSD 6.4
[Unix Hosting |
[Engineering & Automation |
Software Development |