Take the ypchfn/ypchsh stuff that was removed from passwd

and graft it into chpass.

Chpass can now tell when it's being asked to operate on an NIS
user and it displayes the appropriate message in the editor
template ("Changing NIS information for foo"). After the changes
have been made, chpass will promte the user for his NIS password.
If the password is correct, the changes are committed to yppasswdd.

Hopefully, this should make NIS more transparent to the end user.

Note that even the superuser needs to know a user's password before
he can change any NIS information (such is the nature of yppasswdd).
Also, changes to the password field are not permitted -- that's what
yppasswd is for. (The superuser may specify a new password, but
again, he needs to know the user's original password before he can
change it.)

1 files changed, 77 insertions, 1 deletions

diff --git a/chpass/chpass.1 b/chpass/chpass.1
index 534f063..6186c7b 100644
--- a/chpass/chpass.1
+++ b/chpass/chpass.1
@@ -35,7 +35,7 @@
 .Dt CHPASS 1
 .Os
 .Sh NAME
-.Nm chpass
+.Nm chpass, chfn, chsh, ypchpass, ypchfn, ypchsh
 .Nd add or change user database information
 .Sh SYNOPSIS
 chpass
@@ -205,6 +205,72 @@ When the editor terminates, the information is re-read and used to
 update the user database itself.
 Only the user, or the super-user, may edit the information associated
 with the user.
+.Sh NIS INTERACTION
+.Nm Chpass
+can also be used in conjunction with NIS, however some restrictions
+apply.
+Currently,
+.Nm chpass
+can only make changes to the NIS passwd maps through
+.Xr yppasswdd 8 ,
+which only permits changes to a user's password, shell and gecos
+fields. It can not be used to change other user information or to
+add new records to the NIS passwd maps. (Doing that would require
+something such as ypupdated, which is not yet supported.)
+Furthermore,
+.Xr yppasswdd 8
+requires password authentication before it will make any
+changes, even if it receives a request from the super-user.
+.Pp
+As a result, the following restrictions apply when
+.Nm chpass
+is used with NIS:
+.Bl -enum -offset indent
+.It
+.Pa Only the shell and gecos information may be changed.
+All other
+fields are restricted, even when
+.Nm chpass
+is invoked by the super-user, because the
+.Xr yppasswdd 8
+daemon has no support for updating them. While support for
+changing other fields could be added, this would lead to
+compatibility problems with other NIS-capable systems.
+Even though the super-user may supply data for other fields
+while editing an entry, the extra information (other than the
+password -- see below) will be silently discarded.
+.It
+.Pa Password authentication is required.
+.Nm Chpass
+will prompt for the user's NIS password before effecting
+any changes. If the password is invalid, all changes will be
+discarded.
+.It
+.Pa Adding new records to the local
+.Pa password database is discouraged.
+.Nm Chpass
+will allow the administrator to add new records to the
+local password database while NIS is enabled, but this can lead to
+some confusion since the new records are appended to the end of
+the master password file, usually after the special NIS '+' entries.
+The administrator should use
+.Xr vipw 8
+to modify the local password
+file when NIS is running.
+.It
+.Pa Password changes are not permitted.
+Users should use
+.Xr passwd 1
+or
+.Xr yppasswd 1
+to change their NIS passwords. The super-user is allowed to specify
+a new password (even though the ``Password:'' field does not show
+up in the editor template, the super-user may add it back by hand),
+but even the super-user must supply the user's original password
+otherwise
+.Xr yppasswdd 8
+will refuse to update the NIS maps.
+.El
 .Sh FILES
 .Bl -tag -width /etc/master.passwd -compact
 .It Pa /etc/master.passwd
@@ -230,6 +296,16 @@ and
 .%A Ken Thompson
 .%T "UNIX Password security"
 .Re
+.Sh NOTES
+The
+.Xr chfn 1 ,
+.Xr chsh 1 ,
+.Xr ypchpass 1 ,
+.Xr ypchfn 1
+and
+.Xr upchsh 1
+commands are really only links to
+.Nm chpass .
 .Sh BUGS
 User information should (and eventually will) be stored elsewhere.
 .Sh HISTORY