[Abstract] [Copyright Notice] [Contents]

# User service daemon and client specification

## Abstract

This is a specification for a Unix system facility to allow one program to invoke another when only limited trust exists between them.

## Copyright Notice

`userv` is Copyright 1996-1999 Ian Jackson.

`userv` is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with `userv`; if not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

## Contents

- 1 Introduction
- 2 Client program usage
  - 2.1 Options
  - 2.2 Security-overriding options
- 3 Execution environment of the service program
  - 3.1 File descriptors
  - 3.2 Environment
- 4 Service-side configuration
  - 4.1 Configuration file syntax
  - 4.2 Configuration file directives
  - 4.3 Errors in the configuration file
  - 4.4 Defaults
- 5 Information passed through the client/daemon combination
- 6 Applications and notes on use
  - 6.1 Standard services and directory management
  - 6.2 Reducing the number of absolutely privileged subsystems
  - 6.3 Do not give away excessive privilege to `userv`-using facilities
  - 6.4 `userv` is not a replacement for `really` and `sudo`
  - 6.5 Don't give access to general-purpose utilities

[Abstract] [Copyright Notice] [Contents]

User service daemon and client specification