asroot(ADM)                     19 June 1992                     asroot(ADM)


 Name

    asroot - run a command as root

 Syntax

    /tcb/bin/asroot command [ args ]

 Description

    asroot allows an authorized user to run a command as superuser (root).
    Commands that can be used with asroot are defined by the super user (see
    ``Making a command executable under asroot'') and must be present in the
    /tcb/files/rootcmds directory.  Only root can make entries in this direc-
    tory.

    To use asroot, the user must have either the root primary subsystem
    authorization (which allows any command in the rootcmds directory to be
    run) or have a secondary subsystem authorization with the same name as
    the command. In addition to one of these the user must also have the
    execsuid kernel authorization.

    By default, asroot asks the user for their account password before exe-
    cuting the command.  (This prevents an unauthorized user from using a
    terminal which an authorized user has left without logging out.)  This
    feature can be turned off by entering the line ``ASROOTPW=NO'' in
    /etc/default/su.  asroot also logs its use by making entries in the SULOG
    logfile as configured in /etc/default/su.

    If the command to run is a shell script then it will be executed by the
    Bourne (/bin/sh) shell.  The setting of the SHELL environment variable is
    not considered.

    Making a command executable by asroot

    To make a command executable by asroot, log in as root and do the follow-
    ing:

    1.  Copy the desired command into the /tcb/files/rootcmds directory.  Do
        not create a link if the permissions on the file are less restrictive
        than those listed in the File Control database.

    2.  Change the permissions on the file to match those specified in the
        File Control database.  This can be done most conveniently with the
        fixmog(ADM) command.

    3.  Edit the authorizations file /etc/auth/system/authorize and add a
        comma and the name of the new command to the end of the line begin-
        ning with ``root:''.  This declares a new secondary subsystem author-
        ization that can be given to users like any other authorization with
        the sysadmsh(ADM) Accounts -> User -> Examine:Privileges selection.
        Users can only execute the command with asroot if they have the root
        authorization or the authorization corresponding to the name of the
        command.


    Default asroot commands

    By default one command is shipped in the /tcb/files/rootcmds directory:
    the shutdown(ADM) command.  Only trusted users should be given the root
    authorization.

 Files

    /tcb/files/rootcmds         asroot commands
    /etc/auth/system/authorize  subsystem authorizations
    /etc/auth/system/files      File Control database
    /etc/default/su             ASROOTPW and SULOG settings

 See also

    authsh(ADM), fixmog(ADM), integrity(ADM), subsystems(S)

 Diagnostics

    asroot returns an exit code of 1 when:

    1.  the length of the command name is greater than 16 characters

    2.  the user is not authorized to run the command

    3.  the command's execution bits in the /tcb/files/rootcmds directory are
        not set properly

    4.  an integrity violation is detected

    5.  an authentication error is detected

    6.  an incorrect user password is entered

    asroot will also return an exit code of 2 when no command name is given
    or exit code of 3 if the command cannot be executed.

 Notes

    asroot checks the permissions of the complete pathname of all files it
    uses.  If any component of a path does not match its entry in the File
    Control database, an integrity violation is reported.  Run integrity(ADM)
    or fixmog(ADM) to discover where the integrity violation has occurred.

    Care must be taken, when choosing commands to be executed by asroot, that
    the root privilege is not given away accidentally.  For example, if
    sysadmsh(ADM) were to be run via asroot then any shell escapes would also
    run as root.

    A line in /etc/auth/system/authorize cannot exceed 1024 characters in
    length and the sum of the number of primary and secondary authorizations
    cannot exceed 32.

 Value added

    asroot is an extension of AT&T System V provided by The Santa Cruz Opera-
    tion, Inc.