.TH PASSWD 1
.SH NAME
passwd, netkey \- change user password
.SH SYNOPSIS
.B passwd
.PP
.B netkey
.SH DESCRIPTION
.I Passwd
changes the invoker's Plan 9 password.
The program prompts for the old password and then for the new one.
The new password must be typed twice, to forestall mistakes.
New passwords must be sufficiently hard to guess.
They may of any length greater than seven characters.
.PP
.I Netkey
uses the password to encrypt network challenges.
It is a substitute for a SecureNet box.
.PP
These commands may be run only on a terminal, to avoid
transmitting clear text passwords over the network.
.SH FILES
.B /dev/key
.SH SOURCE
.B /sys/src/cmd/auth/passwd.c
.br
.B /sys/src/cmd/auth/netkey.c
.SH "SEE ALSO"
.IR encrypt (2),
.IR cons (3),
.IR securenet (8)
.PP
Robert Morris and Ken Thompson,
``UNIX Password Security,''
.I AT&T Bell Laboratories Technical Journal
Vol 63 (1984), pp. 1649-1672
