As a compromise between usability and security, do not disable
AP PIN permanently based on failed PIN validations. Instead, go to
AP Setup Locked state for increasing amount of time between each
failure to slow down brute force attacks against the AP PIN.
This avoids problems with some external Registrars that may try
to use the same PIN multiple times without user input. Now, the
user will still be able to fix the PIN and try again later while
a real attack is delayed enough to make it impractical.
This allows external programs (e.g., UI) to get more information
about server certificate chain used during TLS handshake. This can
be used both to automatically probe the authentication server to
figure out most likely network configuration and to get information
about reasons for failed authentications.
The follow new control interface events are used for this:
CTRL-EVENT-EAP-PEER-CERT
CTRL-EVENT-EAP-TLS-CERT-ERROR
In addition, there is now an option for matching the server certificate
instead of the full certificate chain for cases where a trusted CA is
not configured or even known. This can be used, e.g., by first probing
the network and learning the server certificate hash based on the new
events and then adding a network configuration with the server
certificate hash after user have accepted it. Future connections will
then be allowed as long as the same server certificate is used.
Authentication server probing can be done, e.g., with following
configuration options:
eap=TTLS PEAP TLS
identity=""
ca_cert="probe://"
Example set of control events for this:
CTRL-EVENT-EAP-STARTED EAP authentication started
CTRL-EVENT-EAP-PROPOSED-METHOD vendor=0 method=21
CTRL-EVENT-EAP-METHOD EAP vendor 0 method 21 (TTLS) selected
CTRL-EVENT-EAP-PEER-CERT depth=0 subject='/C=US/ST=California/L=San Francisco/CN=Server/emailAddress=server@kir.nu' hash=5a1bc1296205e6fdbe3979728efe3920798885c1c4590b5f90f43222d239ca6a
CTRL-EVENT-EAP-TLS-CERT-ERROR reason=8 depth=0 subject='/C=US/ST=California/L=San Francisco/CN=Server/emailAddress=server@kir.nu' err='Server certificate chain probe'
CTRL-EVENT-EAP-FAILURE EAP authentication failed
Server certificate matching is configured with ca_cert, e.g.:
ca_cert="hash://server/sha256/5a1bc1296205e6fdbe3979728efe3920798885c1c4590b5f90f43222d239ca6a"
This functionality is currently available only with OpenSSL. Other
TLS libraries (including internal implementation) may be added in
the future.
If a Registrar tries to configure the AP, but fails to validate the
device password (AP PIN), lock the AP setup after four failures. This
protects the AP PIN against brute force guessing attacks.
Some WPS APs do not set Selected Registrar attribute to 1 properly when
using an external Registrar. Allow such an AP to be selected for PIN
registration after couple of scan runs that do not find APs marked with
Selected Registrar = 1. This allows wpa_supplicant to iterate through
all APs that advertise WPS support without delaying connection with
implementations that set Selected Registrar = 1 properly.
This operation can now be moved into an external program by configuring
hostapd with wps_cred_processing=1 and skip_cred_build=1. A new
ctrl_iface message (WPS-REG-SUCCESS <Enrollee MAC addr> <UUID-E>) will
be used to notify external programs of each successful registration and
that can be used as a tricker to move from unconfigured to configured
state.
This callback is now used to stop wpa_supplicant from trying to continue
using parameters (most likely, device password) that do not work in a
loop. In addition, wpa_gui can now notify user of failed registration.
The event callback will be used for various event messages and the M2D
notification is the first such message. It is used to notify wpa_gui
about Registrar not yet knowing the device password (PIN).
Whenever new scan results include WPS AP(s) and the client is not
associated, send a notification message to control interface monitors.
This makes it easier for GUIs to notify the user about possible WPS
availability without having to go through the scan results.
This adds WPS support for both hostapd and wpa_supplicant. Both programs
can be configured to act as WPS Enrollee and Registrar. Both PBC and PIN
methods are supported.
Currently, hostapd has more complete configuration option for WPS
parameters and wpa_supplicant configuration style will likely change in
the future. External Registrars are not yet supported in hostapd or
wpa_supplicant. While wpa_supplicant has initial support for acting as
an Registrar to configure an AP, this is still using number of hardcoded
parameters which will need to be made configurable for proper operation.
