



= Echo Module

The `echo` module an example of the `exec` module configured
with a `program` configuration item set so it can be called
as any other module, i.e.

    echo

The sample `program` below is a trivial example and should be replaced
with something more meaningful.

The return value of the program run determines the result of the exec
instance call as follows:

[options="header,autowidth"]
|===
| Code | Return    | Description
| < 0  | fail      | the module failed.
| = 0  | ok        | the module succeeded.
| = 1  | reject    | the module rejected the user.
| = 2  | fail      | the module failed.
| = 3  | ok        | the module succeeded.
| = 4  | handled   | the module has done everything to handle the request.
| = 5  | invalid   | the user's configuration entry was invalid.
| = 6  | disallow  | the user was locked out.
| = 7  | notfound  | the user was not found.
| = 8  | noop      | the module did nothing.
| = 9  | updated   | the module updated information in the request.
| > 9  | fail      | the module failed.
|===

NOTE: See `doc/configurable_failover` for details.



## Configuration Settings


wait:: Wait for the program to finish.

If we do NOT wait, then the program is "fire and
forget", and any output attributes from it are ignored.

If we are looking for the program to output
attributes, and want to add those attributes to the
request, then we MUST wait for the program to
finish, and therefore set 'wait=yes'



program:: The name of the program to execute, and it's
arguments.

Dynamic translation is done on this field, so things like
the following example will work.



input_pairs:: The attributes which are placed into the
environment variables for the program.

If your program does not require access to values from
environment variables, then do not set this.

Allowed values are:

[options="header,autowidth"]
|===
| Pairs         | Description
| request       | attributes from the request
| config        | attributes from the configuration items list
| reply         | attributes from the reply
| session-state | attributes that persist over multiple request/response rounds.
|===



output_pairs::: Where to place the output attributes (if any) from
the executed program.

The values allowed, and the restrictions as to availability, are the
same as for the `input_pairs`.



shell_escape:: Escape the environment variables.

If this is set, all the RADIUS attributes are capitalised and dashes
replaced with underscores. Also, RADIUS values are surrounded with
double-quotes.

That is to say:

  User-Name=BobUser => USER_NAME="BobUser"



timeout:: Set a time wait for the program to finish.

Default is `10` seconds, which should be plenty for nearly
anything. Range is `1` to `30` seconds.

WARNING: You are strongly encouraged to NOT increase this value.
Decreasing can be used to cause authentication to fail sooner
when you know it's going to fail anyway due to the time taken,
thereby saving resources.


== Default Configuration

```
exec echo {
	wait = yes
	program = "/bin/echo Tmp-String-0 := %{User-Name}"
	input_pairs = request
	output_pairs = reply
	shell_escape = yes
#	timeout = 10
}
```
