# Captcha

## Presentation

Captcha is a security mechanism aimed to prevent robots to submit forms.

Captchas are available on the following forms:

- Login form: where user enters login and password to authenticate
- Password reset by mail form: where user enters mail to recover a lost password
- Register form: where user enters information to create a new account

We use the Perl module Authen::Captcha to generate codes and images, which look like this:

You need to install Perl Authen::Captcha module if you enable Captcha feature.

## Configuration

Go in `General parameters` > `Portal` > `Captcha`:

- Activation in login form: set to 1 to display captcha in login form
- Activation in password reset by mail form: set to 1 to display captcha in password reset by mail form
- Activation in register form: set to 1 to display captcha in register form
- Size: length of captcha
- Captcha module name: Apache session module used to store generated captchas
- Captcha module options: options for above module