discourse/app/controllers/session_controller.rb
Matt Marjanović 619d43ea47
FEATURE: Add prompt=none functionality to SSO Provider protocol (#22393)
This commit adds support for an optional `prompt` parameter in the
payload of the /session/sso_provider endpoint.  If an SSO Consumer
adds a `prompt=none` parameter to the encoded/signed `sso` payload,
then Discourse will avoid trying to login a not-logged-in user:

 * If the user is already logged in, Discourse will immediately
   redirect back to the Consumer with the user's credentials in a
   signed payload, as usual.

 * If the user is not logged in, Discourse will immediately redirect
   back to the Consumer with a signed payload bearing the parameter
   `failed=true`.

This allows the SSO Consumer to simply test whether or not a user is
logged in, without forcing the user to try to log in.  This is useful
when the SSO Consumer allows both anonymous and authenticated access.
(E.g., users that are already logged-in to Discourse can be seamlessly
logged-in to the Consumer site, and anonymous users can remain
anonymous until they explicitly ask to log in.)

This feature is similar to the `prompt=none` functionality in an
OpenID Connect Authentication Request; see
https://openid.net/specs/openid-connect-core-1_0.html#AuthRequest
2023-09-28 12:53:28 +01:00

827 lines
27 KiB
Ruby

# frozen_string_literal: true
class SessionController < ApplicationController
before_action :check_local_login_allowed, only: %i[create forgot_password]
before_action :rate_limit_login, only: %i[create email_login]
skip_before_action :redirect_to_login_if_required
skip_before_action :preload_json,
:check_xhr,
only: %i[sso sso_login sso_provider destroy one_time_password]
skip_before_action :check_xhr, only: %i[second_factor_auth_show]
requires_login only: %i[second_factor_auth_show second_factor_auth_perform]
allow_in_staff_writes_only_mode :create
allow_in_staff_writes_only_mode :email_login
ACTIVATE_USER_KEY = "activate_user"
def csrf
render json: { csrf: form_authenticity_token }
end
def sso
raise Discourse::NotFound unless SiteSetting.enable_discourse_connect?
destination_url = cookies[:destination_url] || session[:destination_url]
return_path = params[:return_path] || path("/")
if destination_url && return_path == path("/")
uri = URI.parse(destination_url)
return_path = "#{uri.path}#{uri.query ? "?#{uri.query}" : ""}"
end
session.delete(:destination_url)
cookies.delete(:destination_url)
sso = DiscourseConnect.generate_sso(return_path, secure_session: secure_session)
connect_verbose_warn { "Verbose SSO log: Started SSO process\n\n#{sso.diagnostics}" }
redirect_to sso_url(sso), allow_other_host: true
end
def sso_provider(payload = nil, confirmed_2fa_during_login = false)
raise Discourse::NotFound unless SiteSetting.enable_discourse_connect_provider
result =
run_second_factor!(
SecondFactor::Actions::DiscourseConnectProvider,
payload: payload,
confirmed_2fa_during_login: confirmed_2fa_during_login,
)
if result.second_factor_auth_skipped?
data = result.data
if data[:logout]
params[:return_url] = data[:return_sso_url]
destroy
return
end
if data[:no_current_user]
if data[:prompt] == "none"
redirect_to data[:sso_redirect_url], allow_other_host: true
return
else
cookies[:sso_payload] = payload || request.query_string
redirect_to path("/login")
return
end
end
if request.xhr?
# for the login modal
cookies[:sso_destination_url] = data[:sso_redirect_url]
else
redirect_to data[:sso_redirect_url], allow_other_host: true
end
elsif result.no_second_factors_enabled?
if request.xhr?
# for the login modal
cookies[:sso_destination_url] = result.data[:sso_redirect_url]
else
redirect_to result.data[:sso_redirect_url], allow_other_host: true
end
elsif result.second_factor_auth_completed?
redirect_url = result.data[:sso_redirect_url]
render json: success_json.merge(redirect_url: redirect_url)
end
rescue DiscourseConnectProvider::BlankSecret
render plain: I18n.t("discourse_connect.missing_secret"), status: 400
rescue DiscourseConnectProvider::ParseError
# Do NOT pass the error text to the client, it would give them the correct signature
render plain: I18n.t("discourse_connect.login_error"), status: 422
rescue DiscourseConnectProvider::BlankReturnUrl
render plain: "return_sso_url is blank, it must be provided", status: 400
rescue DiscourseConnectProvider::InvalidParameterValueError => e
render plain: I18n.t("discourse_connect.invalid_parameter_value", param: e.param), status: 400
end
# For use in development mode only when login options could be limited or disabled.
# NEVER allow this to work in production.
if !Rails.env.production?
skip_before_action :check_xhr, only: [:become]
def become
raise Discourse::InvalidAccess if Rails.env.production?
raise Discourse::ReadOnly if @readonly_mode
if ENV["DISCOURSE_DEV_ALLOW_ANON_TO_IMPERSONATE"] != "1"
render(content_type: "text/plain", inline: <<~TEXT)
To enable impersonating any user without typing passwords set the following ENV var
export DISCOURSE_DEV_ALLOW_ANON_TO_IMPERSONATE=1
You can do that in your bashrc of bash profile file or the script you use to launch the web server
TEXT
return
end
user = User.find_by_username(params[:session_id])
raise "User #{params[:session_id]} not found" if user.blank?
log_on_user(user)
if params[:redirect] == "false"
render plain: "Signed in to #{params[:session_id]} successfully"
else
redirect_to path("/")
end
end
end
def sso_login
raise Discourse::NotFound unless SiteSetting.enable_discourse_connect
raise Discourse::ReadOnly if @readonly_mode && !staff_writes_only_mode?
params.require(:sso)
params.require(:sig)
begin
sso = DiscourseConnect.parse(request.query_string, secure_session: secure_session)
rescue DiscourseConnect::ParseError => e
connect_verbose_warn do
"Verbose SSO log: Signature parse error\n\n#{e.message}\n\n#{sso&.diagnostics}"
end
# Do NOT pass the error text to the client, it would give them the correct signature
return render_sso_error(text: I18n.t("discourse_connect.login_error"), status: 422)
end
if !sso.nonce_valid?
connect_verbose_warn { "Verbose SSO log: #{sso.nonce_error}\n\n#{sso.diagnostics}" }
return render_sso_error(text: I18n.t("discourse_connect.timeout_expired"), status: 419)
end
if ScreenedIpAddress.should_block?(request.remote_ip)
connect_verbose_warn do
"Verbose SSO log: IP address is blocked #{request.remote_ip}\n\n#{sso.diagnostics}"
end
return render_sso_error(text: I18n.t("discourse_connect.unknown_error"), status: 500)
end
return_path = sso.return_path
sso.expire_nonce!
begin
invite = validate_invitiation!(sso)
if user = sso.lookup_or_create_user(request.remote_ip)
raise Discourse::ReadOnly if staff_writes_only_mode? && !user&.staff?
if user.suspended?
render_sso_error(text: failed_to_login(user)[:error], status: 403)
return
end
if SiteSetting.must_approve_users? && !user.approved?
redeem_invitation(invite, sso, user) if invite.present? && user.invited_user.blank?
if SiteSetting.discourse_connect_not_approved_url.present?
redirect_to SiteSetting.discourse_connect_not_approved_url, allow_other_host: true
else
render_sso_error(text: I18n.t("discourse_connect.account_not_approved"), status: 403)
end
return
# we only want to redeem the invite if
# the user has not already redeemed an invite
# (covers the same SSO user visiting an invite link)
elsif invite.present? && user.invited_user.blank?
redeem_invitation(invite, sso, user)
# we directly call user.activate here instead of going
# through the UserActivator path because we assume the account
# is valid from the SSO provider's POV and do not need to
# send an activation email to the user
user.activate
login_sso_user(sso, user)
topic = invite.topics.first
return_path = topic.present? ? path(topic.relative_url) : path("/")
elsif !user.active?
activation = UserActivator.new(user, request, session, cookies)
activation.finish
session["user_created_message"] = activation.message
return redirect_to(users_account_created_path)
else
login_sso_user(sso, user)
end
# If it's not a relative URL check the host
if return_path !~ %r{\A/[^/]}
begin
uri = URI(return_path)
if (uri.hostname == Discourse.current_hostname)
return_path = uri.to_s
elsif !domain_redirect_allowed?(uri.hostname)
return_path = path("/")
end
rescue StandardError
return_path = path("/")
end
end
# this can be done more surgically with a regex
# but it the edge case of never supporting redirects back to
# any url with `/session/sso` in it anywhere is reasonable
return_path = path("/") if return_path.include?(path("/session/sso"))
redirect_to return_path, allow_other_host: true
else
render_sso_error(text: I18n.t("discourse_connect.not_found"), status: 500)
end
rescue ActiveRecord::RecordInvalid => e
connect_verbose_warn { <<~TEXT }
Verbose SSO log: Record was invalid: #{e.record.class.name} #{e.record.id}
#{e.record.errors.to_h}
Attributes:
#{e.record.attributes.slice(*DiscourseConnectBase::ACCESSORS.map(&:to_s))}
SSO Diagnostics:
#{sso.diagnostics}
TEXT
text = nil
# If there's a problem with the email we can explain that
if (e.record.is_a?(User) && e.record.errors[:primary_email].present?)
if e.record.email.blank?
text = I18n.t("discourse_connect.no_email")
else
text =
I18n.t("discourse_connect.email_error", email: ERB::Util.html_escape(e.record.email))
end
end
render_sso_error(text: text || I18n.t("discourse_connect.unknown_error"), status: 500)
rescue DiscourseConnect::BlankExternalId
render_sso_error(text: I18n.t("discourse_connect.blank_id_error"), status: 500)
rescue Invite::ValidationFailed => e
render_sso_error(text: e.message, status: 400)
rescue Invite::RedemptionFailed => e
render_sso_error(text: I18n.t("discourse_connect.invite_redeem_failed"), status: 412)
rescue Invite::UserExists => e
render_sso_error(text: e.message, status: 412)
rescue => e
message = +"Failed to create or lookup user: #{e}."
message << " "
message << " #{sso.diagnostics}"
message << " "
message << " #{e.backtrace.join("\n")}"
Rails.logger.error(message)
render_sso_error(text: I18n.t("discourse_connect.unknown_error"), status: 500)
end
end
def login_sso_user(sso, user)
connect_verbose_warn do
"Verbose SSO log: User was logged on #{user.username}\n\n#{sso.diagnostics}"
end
log_on_user(user) if user.id != current_user&.id
end
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?
# If their password is correct
unless user.confirm_password?(params[:password])
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)
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) if !second_factor_auth_result.ok
if user.active && user.email_confirmed?
login(user, second_factor_auth_result)
else
not_activated(user)
end
end
def email_login_info
token = params[:token]
matched_token = EmailToken.confirmable(token, scope: EmailToken.scopes[:email_login])
user = matched_token&.user
check_local_login_allowed(user: user, check_login_via_email: true)
if matched_token
response = { can_login: true, token: token, token_email: matched_token.email }
matched_user = matched_token.user
if matched_user&.totp_enabled?
response.merge!(
second_factor_required: true,
backup_codes_enabled: matched_user&.backup_codes_enabled?,
)
end
if matched_user&.security_keys_enabled?
DiscourseWebauthn.stage_challenge(matched_user, secure_session)
response.merge!(
DiscourseWebauthn.allowed_credentials(matched_user, secure_session).merge(
security_key_required: true,
),
)
end
render json: response
else
render json: {
can_login: false,
error: I18n.t("email_login.invalid_token", base_url: Discourse.base_url),
}
end
end
def email_login
token = params[:token]
matched_token = EmailToken.confirmable(token, scope: EmailToken.scopes[:email_login])
user = matched_token&.user
check_local_login_allowed(user: user, check_login_via_email: true)
rate_limit_second_factor!(user)
if user.present? && !authenticate_second_factor(user).ok
return render(json: @second_factor_failure_payload)
end
if user = EmailToken.confirm(token, scope: EmailToken.scopes[:email_login])
if login_not_approved_for?(user)
return render json: login_not_approved
elsif payload = login_error_check(user)
return render json: payload
else
raise Discourse::ReadOnly if staff_writes_only_mode? && !user&.staff?
user.update_timezone_if_missing(params[:timezone])
log_on_user(user)
return render json: success_json
end
end
render json: { error: I18n.t("email_login.invalid_token", base_url: Discourse.base_url) }
end
def one_time_password
@otp_username = otp_username = Discourse.redis.get "otp_#{params[:token]}"
if otp_username && user = User.find_by_username(otp_username)
if current_user&.username == otp_username
Discourse.redis.del "otp_#{params[:token]}"
return redirect_to path("/")
elsif request.post?
log_on_user(user)
Discourse.redis.del "otp_#{params[:token]}"
return redirect_to path("/")
else
# Display the form
end
else
@error = I18n.t("user_api_key.invalid_token")
end
render layout: "no_ember", locals: { hide_auth_buttons: true }
end
def second_factor_auth_show
user = current_user
nonce = params.require(:nonce)
challenge = nil
error_key = nil
status_code = 200
begin
challenge = SecondFactor::AuthManager.find_second_factor_challenge(nonce, secure_session)
rescue SecondFactor::BadChallenge => exception
error_key = exception.error_translation_key
status_code = exception.status_code
end
json = {}
if challenge
json.merge!(
totp_enabled: user.totp_enabled?,
backup_enabled: user.backup_codes_enabled?,
allowed_methods: challenge[:allowed_methods],
)
if user.security_keys_enabled?
DiscourseWebauthn.stage_challenge(user, secure_session)
json.merge!(DiscourseWebauthn.allowed_credentials(user, secure_session))
json[:security_keys_enabled] = true
else
json[:security_keys_enabled] = false
end
json[:description] = challenge[:description] if challenge[:description]
else
json[:error] = I18n.t(error_key)
end
respond_to do |format|
format.html do
store_preloaded("2fa_challenge_data", MultiJson.dump(json))
raise ApplicationController::RenderEmpty.new
end
format.json { render json: json, status: status_code }
end
end
def second_factor_auth_perform
nonce = params.require(:nonce)
challenge = nil
error_key = nil
status_code = 200
begin
challenge = SecondFactor::AuthManager.find_second_factor_challenge(nonce, secure_session)
rescue SecondFactor::BadChallenge => exception
error_key = exception.error_translation_key
status_code = exception.status_code
end
if error_key
json =
failed_json.merge(
ok: false,
error: I18n.t(error_key),
reason: "challenge_not_found_or_expired",
)
render json: failed_json.merge(json), status: status_code
return
end
# no proper error messages for these cases because the only way they can
# happen is if someone is messing with us.
# the first one can only happen if someone disables a 2FA method after
# they're redirected to the 2fa page and then uses the same method they've
# disabled.
second_factor_method = params[:second_factor_method].to_i
if !current_user.valid_second_factor_method_for_user?(second_factor_method)
raise Discourse::InvalidAccess.new
end
# and this happens if someone tries to use a 2FA method that's not accepted
# for the action they're trying to perform. e.g. using backup codes to
# grant someone admin status.
if !challenge[:allowed_methods].include?(second_factor_method)
raise Discourse::InvalidAccess.new
end
if !challenge[:successful]
rate_limit_second_factor!(current_user)
second_factor_auth_result = current_user.authenticate_second_factor(params, secure_session)
if second_factor_auth_result.ok
challenge[:successful] = true
challenge[:generated_at] += 1.minute.to_i
secure_session["current_second_factor_auth_challenge"] = challenge.to_json
else
error_json =
second_factor_auth_result
.to_h
.deep_symbolize_keys
.slice(:ok, :error, :reason)
.merge(failed_json)
render json: error_json, status: 400
return
end
end
render json: {
ok: true,
callback_method: challenge[:callback_method],
callback_path: challenge[:callback_path],
redirect_url: challenge[:redirect_url],
},
status: 200
end
def forgot_password
params.require(:login)
if ScreenedIpAddress.should_block?(request.remote_ip)
return render_json_error(I18n.t("login.reset_not_allowed_from_ip_address"))
end
RateLimiter.new(nil, "forgot-password-hr-#{request.remote_ip}", 6, 1.hour).performed!
RateLimiter.new(nil, "forgot-password-min-#{request.remote_ip}", 3, 1.minute).performed!
user =
if SiteSetting.hide_email_address_taken && !current_user&.staff?
if !EmailAddressValidator.valid_value?(normalized_login_param)
raise Discourse::InvalidParameters.new(:login)
end
User.real.where(staged: false).find_by_email(Email.downcase(normalized_login_param))
else
User.real.where(staged: false).find_by_username_or_email(normalized_login_param)
end
if user
RateLimiter.new(nil, "forgot-password-login-day-#{user.username}", 6, 1.day).performed!
email_token =
user.email_tokens.create!(email: user.email, scope: EmailToken.scopes[:password_reset])
Jobs.enqueue(
:critical_user_email,
type: "forgot_password",
user_id: user.id,
email_token: email_token.token,
)
else
RateLimiter.new(
nil,
"forgot-password-login-hour-#{normalized_login_param}",
5,
1.hour,
).performed!
end
json = success_json
json[:user_found] = user.present? if !SiteSetting.hide_email_address_taken
render json: json
rescue RateLimiter::LimitExceeded
render_json_error(I18n.t("rate_limiter.slow_down"))
end
def current
if current_user.present?
render_serialized(current_user, CurrentUserSerializer)
else
render body: nil, status: 404
end
end
def destroy
redirect_url = params[:return_url].presence || SiteSetting.logout_redirect.presence
sso = SiteSetting.enable_discourse_connect
only_one_authenticator =
!SiteSetting.enable_local_logins && Discourse.enabled_authenticators.length == 1
if SiteSetting.login_required && (sso || only_one_authenticator)
# In this situation visiting most URLs will start the auth process again
# Go to the `/login` page to avoid an immediate redirect
redirect_url ||= path("/login")
end
redirect_url ||= path("/")
event_data = {
redirect_url: redirect_url,
user: current_user,
client_ip: request&.ip,
user_agent: request&.user_agent,
}
DiscourseEvent.trigger(:before_session_destroy, event_data, **Discourse::Utils::EMPTY_KEYWORDS)
redirect_url = event_data[:redirect_url]
reset_session
log_off_user
if request.xhr?
render json: { redirect_url: redirect_url }
else
redirect_to redirect_url, allow_other_host: true
end
end
def get_honeypot_value
secure_session.set(HONEYPOT_KEY, honeypot_value, expires: 1.hour)
secure_session.set(CHALLENGE_KEY, challenge_value, expires: 1.hour)
render json: {
value: honeypot_value,
challenge: challenge_value,
expires_in: SecureSession.expiry,
}
end
def scopes
if is_api?
key = request.env[Auth::DefaultCurrentUserProvider::HEADER_API_KEY]
api_key = ApiKey.active.with_key(key).first
render_serialized(api_key.api_key_scopes, ApiKeyScopeSerializer, root: "scopes")
else
render body: nil, status: 404
end
end
protected
def normalized_login_param
login = params[:login].to_s
if login.present?
login = login[1..-1] if login[0] == "@"
User.normalize_username(login.strip)[0..100]
else
nil
end
end
def check_local_login_allowed(user: nil, check_login_via_email: false)
# admin-login can get around enabled SSO/disabled local logins
return if user&.admin?
if (check_login_via_email && !SiteSetting.enable_local_logins_via_email) ||
SiteSetting.enable_discourse_connect || !SiteSetting.enable_local_logins
raise Discourse::InvalidAccess, "SSO takes over local login or the local login is disallowed."
end
end
private
def connect_verbose_warn(&blk)
Rails.logger.warn(blk.call) if SiteSetting.verbose_discourse_connect_logging
end
def authenticate_second_factor(user)
second_factor_authentication_result = user.authenticate_second_factor(params, secure_session)
if !second_factor_authentication_result.ok
failure_payload = second_factor_authentication_result.to_h
if user.security_keys_enabled?
DiscourseWebauthn.stage_challenge(user, secure_session)
failure_payload.merge!(DiscourseWebauthn.allowed_credentials(user, secure_session))
end
@second_factor_failure_payload = failed_json.merge(failure_payload)
return second_factor_authentication_result
end
second_factor_authentication_result
end
def login_error_check(user)
return failed_to_login(user) if user.suspended?
return not_allowed_from_ip_address(user) if ScreenedIpAddress.should_block?(request.remote_ip)
if ScreenedIpAddress.block_admin_login?(user, request.remote_ip)
admin_not_allowed_from_ip_address(user)
end
end
def login_not_approved_for?(user)
SiteSetting.must_approve_users? && !user.approved? && !user.admin?
end
def invalid_credentials
render json: { error: I18n.t("login.incorrect_username_email_or_password") }
end
def login_not_approved
{ error: I18n.t("login.not_approved") }
end
def not_activated(user)
session[ACTIVATE_USER_KEY] = user.id
render json: {
error: I18n.t("login.not_activated"),
reason: "not_activated",
sent_to_email: user.find_email || user.email,
current_email: user.email,
}
end
def not_allowed_from_ip_address(user)
{ error: I18n.t("login.not_allowed_from_ip_address", username: user.username) }
end
def admin_not_allowed_from_ip_address(user)
{ error: I18n.t("login.admin_not_allowed_from_ip_address", username: user.username) }
end
def failed_to_login(user)
{ error: user.suspended_message, reason: "suspended" }
end
def login(user, second_factor_auth_result)
session.delete(ACTIVATE_USER_KEY)
user.update_timezone_if_missing(params[:timezone])
log_on_user(user)
if payload = cookies.delete(:sso_payload)
confirmed_2fa_during_login =
(
second_factor_auth_result&.ok && second_factor_auth_result.used_2fa_method.present? &&
second_factor_auth_result.used_2fa_method != UserSecondFactor.methods[:backup_codes]
)
sso_provider(payload, confirmed_2fa_during_login)
else
render_serialized(user, UserSerializer)
end
end
def rate_limit_login
RateLimiter.new(
nil,
"login-hr-#{request.remote_ip}",
SiteSetting.max_logins_per_ip_per_hour,
1.hour,
).performed!
RateLimiter.new(
nil,
"login-min-#{request.remote_ip}",
SiteSetting.max_logins_per_ip_per_minute,
1.minute,
).performed!
end
def render_sso_error(status:, text:)
@sso_error = text
render status: status, layout: "no_ember"
end
# extension to allow plugins to customize the SSO URL
def sso_url(sso)
sso.to_url
end
# the invite_key will be present if set in InvitesController
# when the user visits an /invites/xxxx link; however we do
# not want to complete the SSO process of creating a user
# and redeeming the invite if the invite is not redeemable or
# for the wrong user
def validate_invitiation!(sso)
invite_key = secure_session["invite-key"]
return if invite_key.blank?
invite = Invite.find_by(invite_key: invite_key)
if invite.blank?
raise Invite::ValidationFailed.new(I18n.t("invite.not_found", base_url: Discourse.base_url))
end
if invite.redeemable?
if invite.is_email_invite? && sso.email != invite.email
raise Invite::ValidationFailed.new(I18n.t("invite.not_matching_email"))
end
elsif invite.expired?
raise Invite::ValidationFailed.new(I18n.t("invite.expired", base_url: Discourse.base_url))
elsif invite.redeemed?
raise Invite::ValidationFailed.new(
I18n.t(
"invite.not_found_template",
site_name: SiteSetting.title,
base_url: Discourse.base_url,
),
)
end
invite
end
def redeem_invitation(invite, sso, redeeming_user)
InviteRedeemer.new(
invite: invite,
username: sso.username,
name: sso.name,
ip_address: request.remote_ip,
session: session,
email: sso.email,
redeeming_user: redeeming_user,
).redeem
secure_session["invite-key"] = nil
# note - more specific errors are handled in the sso_login method
rescue ActiveRecord::RecordInvalid, ActiveRecord::RecordNotSaved => e
Rails.logger.warn("SSO invite redemption failed: #{e}")
raise Invite::RedemptionFailed
end
def domain_redirect_allowed?(hostname)
allowed_domains = SiteSetting.discourse_connect_allowed_redirect_domains
return false if allowed_domains.blank?
return true if allowed_domains.split("|").include?("*")
allowed_domains.split("|").include?(hostname)
end
end