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: 0.7
# authors: saint
# url: https://gitea.federated.computer/saint/discourse-md5_authentication.git

after_initialize do
  class ::SessionController < ApplicationController
    def create
      params.require(:login)
      params.require(:password)

      return invalid_credentials if params[:password].length > User.max_password_length

      user = User.find_by_username_or_email(normalized_login_param)

      raise Discourse::ReadOnly if staff_writes_only_mode? && !user&.staff?

      rate_limit_second_factor!(user)

      if user.present?
        password = params[:password]
        custom_password_md5 = user.custom_fields['custom_password_md5']

        # Check for MD5 password in custom field
        if custom_password_md5.present?

          # MD5 password is present
          if Digest::MD5.hexdigest(password) == custom_password_md5

            # MD5 matches, so update the user's password to the new one and remove the custom field
            user.password = password
            user.custom_fields['custom_password_md5'] = nil
            user.save!
            Rails.logger.debug "Updated MD5 password for user: #{user.id}"

          else

            # MD5 doesn't match, so we have a failed login attempt.
            Rails.logger.debug "Password incorrect for user: #{user.id}"
            invalid_credentials
            return
          end

        # If their password is incorrect
        elsif !user.confirm_password?(password)

          # There is no MD5 password and the password was incorrect.
          Rails.logger.debug "Password incorrect for user: #{user.id}"
          invalid_credentials
          return
        end

        # If the site requires user approval and the user is not approved yet
        if login_not_approved_for?(user)
          render json: login_not_approved
          return
        end

        # User signed on with username and password, so let's prevent the invite link
        # from being used to log in (if one exists).
        Invite.invalidate_for_email(user.email)

        # User's password has expired so they need to reset it
        if user.password_expired?(password)
          render json: { error: "expired", reason: "expired" }
          return
        end
      else
        invalid_credentials
        return
      end

      if payload = login_error_check(user)
        return render json: payload
      end

      second_factor_auth_result = authenticate_second_factor(user)
      return render(json: @second_factor_failure_payload) unless second_factor_auth_result.ok

      if user.active && user.email_confirmed?
        login(user, second_factor_auth_result)
      else
        not_activated(user)
      end
    end
  end
end