mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-21 11:13:30 +00:00
30c4fc7cf9
Document the need for the setuid bit and how to set it. Explain why it isn't set by default, and suggest simply adding users to groups instead. PR: docs/167741 MFC after: 3 weeks
105 lines
3.0 KiB
Groff
105 lines
3.0 KiB
Groff
.\" Copyright (c) 2002 Tim J. Robbins.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd February 8, 2013
|
|
.Dt NEWGRP 1
|
|
.Os
|
|
.Sh NAME
|
|
.Nm newgrp
|
|
.Nd change to a new group
|
|
.Sh SYNOPSIS
|
|
.Nm
|
|
.Op Fl l
|
|
.Op Ar group
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
utility creates a new shell execution environment with modified
|
|
real and effective group IDs.
|
|
.Pp
|
|
The options are as follows:
|
|
.Bl -tag -width indent
|
|
.It Fl l
|
|
Simulate a full login.
|
|
The environment and umask are set to what would be expected if the user
|
|
actually logged in again.
|
|
.El
|
|
.Pp
|
|
If the
|
|
.Ar group
|
|
operand is present, a new shell is started with the specified effective
|
|
and real group IDs.
|
|
The user will be prompted for a password if they are not a member of the
|
|
specified group.
|
|
.Pp
|
|
Otherwise, the real, effective and supplementary group IDs are restored to
|
|
those from the current user's password database entry.
|
|
.Sh EXIT STATUS
|
|
The
|
|
.Nm
|
|
utility attempts to start the shell regardless of whether group IDs
|
|
were successfully changed.
|
|
.Pp
|
|
If an error occurs and the shell cannot be started,
|
|
.Nm
|
|
exits >0.
|
|
Otherwise, the exit status of
|
|
.Nm
|
|
is the exit status of the shell.
|
|
.Sh SEE ALSO
|
|
.Xr csh 1 ,
|
|
.Xr groups 1 ,
|
|
.Xr login 1 ,
|
|
.Xr sh 1 ,
|
|
.Xr su 1 ,
|
|
.Xr umask 1 ,
|
|
.Xr group 5 ,
|
|
.Xr passwd 5 ,
|
|
.Xr environ 7
|
|
.Sh STANDARDS
|
|
The
|
|
.Nm
|
|
utility conforms to
|
|
.St -p1003.1-2001 .
|
|
.Sh HISTORY
|
|
A
|
|
.Nm
|
|
utility appeared in
|
|
.At v6 .
|
|
.Sh BUGS
|
|
For security reasons, the
|
|
.Nm
|
|
utility is normally installed without the setuid bit.
|
|
To enable it, run the following command:
|
|
.Bd -literal -offset indent
|
|
chmod u+s /usr/bin/newgrp
|
|
.Ed
|
|
.Pp
|
|
Group passwords are inherently insecure as there is no way to stop
|
|
users obtaining the password hash from the group database.
|
|
Their use is discouraged.
|
|
Instead, users should simply be added to the necessary groups.
|