discourse-md5_authentication/plugin.rb

# plugins/discourse-md5_authentication/plugin.rb

# frozen_string_literal: true

# name: discourse-md5_authentication
# about: A plugin to authenticate users with MD5 passwords from legacy systems
# version: 0.5
# authors: saint
# url: https://gitea.federated.computer/saint/discourse-md5_authentication.git

# This block will run after Discourse has initialized
after_initialize do
  # Define a module to contain the MD5 authentication logic
  module LegacyMd5Authentication
    # Override the current_user method to include MD5 authentication
    def current_user
      # Attempt to find the current user using the standard Discourse method
      user = super
      return user if user

      # Check for MD5 authentication if no user is found by the standard method
      email_or_username = @request.params[:login]
      password = @request.params[:password]

      if email_or_username && password
        # Log the start of the MD5 authentication attempt
        Rails.logger.info("MD5 Auth: Attempting to authenticate #{email_or_username}")

        # Find the user by username or email, ignoring case
        user = User.find_by_username_or_email(email_or_username.downcase.strip)

        # Log if a user with an MD5 password is found
        if user && user.custom_fields['md5_password']
          Rails.logger.info("MD5 Auth: User found with MD5 password - #{user.username}")

          # Check if the provided password matches the stored MD5 password
          if user.custom_fields['md5_password'] == Digest::MD5.hexdigest(password)
            # Log the successful MD5 password match
            Rails.logger.info("MD5 Auth: MD5 password match for user #{user.username}")

            # Update the user to use the new password and clear the MD5 password
            user.update!(password: password)
            user.custom_fields['md5_password'] = nil
            user.save_custom_fields

            # Set the current user in the environment
            @env[CURRENT_USER_KEY] = user
            return user
          end
        end
      end

      # Fallback to the original current_user method
      nil
    end
  end

  # Prepend our module to the DefaultCurrentUserProvider class
  Auth::DefaultCurrentUserProvider.prepend LegacyMd5Authentication
end