| .TH PASSWD 1 |
| .SH NAME |
| passwd, netkey \- change user password |
| .SH SYNOPSIS |
| .B passwd |
| [ |
| .I username\fR[@\fPdomain\fR]\fP |
| ] |
| .PP |
| .B netkey |
| .SH DESCRIPTION |
| .I Passwd |
| changes the invoker's Plan 9 password and/or APOP secret. |
| The Plan 9 password is used to login to a terminal while |
| the APOP secret is used for a number of external services: |
| POP3, IMAP, and VPN access. The optional argument specifies |
| the user name and authentication domain to use if different |
| than the one associated with the machine |
| .I passwd |
| is run on. |
| .PP |
| The program first prompts for the old Plan 9 password in the specified |
| domain to establish |
| identity. |
| It then prompts for changes to the password and the |
| secret. |
| New passwords and secrets must be typed twice, to forestall mistakes. |
| New passwords must be sufficiently hard to guess. |
| They may be of any length greater than seven characters. |
| .PP |
| .I Netkey |
| prompts for a password to encrypt network challenges. |
| It is a substitute for a SecureNet box. |
| .SH SOURCE |
| .B \*9/src/cmd/netkey.c |
| .br |
| .B \*9/src/cmd/auth/passwd.c |
| .SH "SEE ALSO" |
| .IR encrypt (3) |
| .PP |
| Robert Morris and Ken Thompson, |
| ``UNIX Password Security,'' |
| .I AT&T Bell Laboratories Technical Journal |
| Vol 63 (1984), pp. 1649-1672 |
