shadow/man/pwconv.8

.\"$Id: pwconv.8,v 1.17 2005/05/19 10:34:59 kloczek Exp $
.TH PWCONV 8 "26 Sep 1997"
.SH NAME
pwconv, pwunconv, grpconv, grpunconv \- convert to and from shadow passwords and groups.
.SH SYNOPSIS
\fBpwconv\fR
.br
\fBpwunconv\fR
.br
\fBgrpconv\fR
.br
\fBgrpunconv\fR
.SH DESCRIPTION
\fBpwconv\fR creates \fIshadow\fR from \fIpasswd\fR and an optionally existing
\fIshadow\fR.
.PP
\fBpwunconv\fR creates \fIpasswd\fR from \fIpasswd\fR and \fIshadow\fR and then
removes \fIshadow\fR.
.PP
\fBgrpconv\fR creates \fIgshadow\fR from \fIgroup\fR and an optionally existing
\fIgshadow\fR.
.PP
\fBgrpunconv\fR creates \fIgroup\fR from \fIgroup\fR and \fIgshadow\fR and then
removes \fIgshadow\fR.
.PP
These four programs all operate on the normal and shadow password and group
files: \fI/etc/passwd\fR, \fI/etc/group\fR, \fI/etc/shadow\fR, and
\fI/etc/gshadow\fR.
.PP
.PP 
Each program acquires the necessary locks before conversion. \fBpwconv\fR and
\fBgrpconv\fR are similar. First, entries in the shadowed file which don't
exist in the main file are removed. Then, shadowed entries which don't have
`x' as the password in the main file are updated. Any missing shadowed
entries are added. Finally, passwords in the main file are replaced with
`x'. These programs can be used for initial conversion as well to update the
shadowed file if the main file is edited by hand.
.PP
\fBpwconv\fR will use the values of \fIPASS_MIN_DAYS\fR, \fIPASS_MAX_DAYS\fR,
and \fIPASS_WARN_AGE\fR from \fI/etc/login.defs\fR when adding new entries
to \fI/etc/shadow\fR.
.PP
Likewise  \fBpwunconv\fR and \fBgrpunconv\fR are similar. Passwords in the
main file are updated from the shadowed file. Entries which exist in the
main file but not in the shadowed file are left alone. Finally, the shadowed
file is removed. Some password aging information is lost by \fBpwunconv\fR.
It will convert what it can.
.SH "BUGS"
Errors in the password or group files (such as invalid or duplicate entries)
may cause these programs to loop forever or fail in other strange ways. 
Please run \fBpwck\fR and \fBgrpck\fR to correct any such errors before
converting to or from shadow passwords or groups.
.SH "SEE ALSO"
.BR login.defs (5),
.BR grpck (8),
.BR pwck (8)