DOAS.CONF(5)

NAME
doas.conf - doas configuration file

SYNOPSIS
/usr/local/etc/doas.conf

DESCRIPTION
The doas(1) utility executes commands as other users according to the rules in the doas.conf configuration file.

The rules have the following format:

permit|deny [options] identity [as target] [cmd command [args ...]]

Rules consist of the following parts:

permit|deny
    The action to be taken if this rule matches.

options
    Options are:

    nopass
        The user is not required to enter a password.

    nolog
        Do not log successful command execution to syslogd.

    persist
        After the user successfully authenticates, do not ask for a password again for some time. Works on OpenBSD only, persist is not available on Linux or FreeBSD.

    keepenv
        The user's environment is maintained. The default is to reset the environment, except for the variables DISPLAY and TERM. Note: In order to be able to run most desktop (GUI) applications, the user needs to have the keepenv keyword specified. If keepenv is not specified then key elements, like the user's $HOME variable, will be reset and cause the GUI application to crash. Users who only need to run command line applications can usually get away without keepenv. When in doubt, try to avoid using keepenv as it is less secure to have environment variables passed to privileged users. Note: The target user's PATH variable can be set at compile time by adjusting the GLOBAL_PATH variable in doas's Makefile. By default, the target user's path will be set to "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:"

    setenv { [variable ...] [variable=value ...] }
        In addition to the variables mentioned above, keep the space-separated specified variables. Variables may also be removed with a leading ‘-’ or set using the latter syntax. If the first character of value is a ‘$’ then the value to be set is taken from the existing environment variable of the same name.

identity
    The username to match. Groups may be specified by prepending a colon (‘’):. Numeric IDs are also accepted.

as target
    The target user the running user is allowed to run the command as. The default is all users. Please be aware that on some systems multiple usernames can resolve to the same UID. For example, on FreeBSD it is common to have both toor and root resolve to UID 0. The doas utility will allow any username that matches a shared UID to match when the -u flag is invoked. This means if you have the rule

        permit alice as toor

    in your doas.conf file, the command "doas -u root" can be successfully run from Alice's account in situations where both root and toor share the same UID. In short, doas cares about the UID behind the username, not the specific username given on the command line.

cmd command
    The command the user is allowed or denied to run. The default is all commands. Be advised that it is best to specify absolute paths. If a relative path is specified, only a restricted PATH will be searched.

args [argument ...]
    Arguments to command. The command arguments provided by the user need to match those specified. The keyword args alone means that command must be run without any arguments.

The last matching rule determines the action taken. If no rule matches, the action is denied.

Comments can be put anywhere in the file using a hash mark (‘#’), and extend to the end of the current line.

The following quoting rules apply:

-   The text between a pair of double quotes (‘"’) is taken as is.

-   The backslash character (‘\’) escapes the next character, including new line characters, outside comments; as a result, comments may not be extended over multiple lines.

-   If quotes or backslashes are used in a word, it is not considered a keyword.

NOTES
To make editing the doas.conf file safer, a convenience script called vidoas is included with the doas software. This script can be run as the root user (or via doas or sudo) and automatically checks the syntax of the doas.conf file before installing it on the system. Please take note that it is a bad idea to assign permission to users implicitly, even if blocking/denying exceptions are made. For instance, try to avoid using rules like

    permit susan as
    deny susan as root

The above example uses two rules to permit Susan to switch to any user, except root. This is dangerous for two reasons. First, it means if new users, including ones with admin access, are added to the system later then Susan can use their accounts. It also means if the file is truncated or accessed while being updated the doas program may read the first rule before the second has been written, giving Susan access to everything, including the root account. The better approach to is explicity allow Susan to access only specific accounts she needs to use. Entries in the doas.conf file must end with a newline character to indicate where a rule ends. Most text editors will add a newline or end of line character for you, however not all tools do. Please make sure each rule in your doas.conf file ends with a newline (Enter) character. Otherwise syntax checks will fail with an error "syntax error at line..."

EXAMPLES
The following example permits users in group wsrc to build ports; wheel to execute commands as any user while keeping the environment variables PS1 and SSH_AUTH_SOCK and unsetting ENV; permits tedu to run procmap as root without a password; and additionally permits root to run unrestricted commands as itself.

    # Non-exhaustive list of variables needed to
    # build release(8) and ports(7)
    permit nopass setenv { \
            FTPMODE PKG_CACHE PKG_PATH SM_PATH SSH_AUTH_SOCK \
            DESTDIR DISTDIR FETCH_CMD FLAVOR GROUP MAKE MAKECONF \
            MULTI_PACKAGES NOMAN OKAY_FILES OWNER PKG_DBDIR \
            PKG_DESTDIR PKG_TMPDIR PORTSDIR RELEASEDIR SHARED_ONLY \
            SUBPACKAGE WRKOBJDIR SUDO_PORT_V1 } :wsrc
    permit setenv { -ENV PS1=$DOAS_PS1 SSH_AUTH_SOCK } :wheel
    permit nopass tedu as root cmd /usr/sbin/procmap
    permit nopass keepenv root as root

SEE ALSO
doas(1)

HISTORY
The doas.conf configuration file first appeared in OpenBSD 5.8.

AUTHORS
Ted Unangst <tedu@openbsd.org>