The change to support fragmentation added extra function to generate the
EAP header, but forgot to remove the original code and ended up getting two
EAP headers and TNC flags field in the generated message. These header
fields need to be added only in the function that builds the final message
(and if necessary, fragments the data).
The server handshake processing was still using SSL_read() to get OpenSSL
to perform the handshake. While this works for most cases, it caused some
issues for re-authentication. This is now changed to use SSL_accept() which
is more approriate here since we know that the handshake is still going on
and there will not be any tunneled data available. This resolves some of
the re-authentication issues and makes it possible for the server to notice
if TLS processing fails (SSL_read() did not return an error in many of
these cases while SSL_accept() does).
Set session id context to a unique value in order to avoid fatal errors
when client tries session resumption (SSL_set_session_id_context() must be
called for that to work), but disable session resumption with the unique
value for the time being since not all server side code is ready for it yet
(e.g., EAP-TTLS needs special Phase 2 processing when using abbreviated
handshake).
Changed EAP-TLS server not to call TLS library when processing the final
ACK (empty data) from the client in order to avoid starting a new TLS
handshake with SSL_accept().
Move the basic processing of received frames into eap_tls_common.c and use
callback functions to handle EAP type specific processing of the version
field and payload.
Fragmentation is now done as a separate step to clean up the design and to
allow the same code to be used in both Phase 1 and Phase 2. This adds
support for fragmenting EAP-PEAP/TTLS/FAST Phase 2 (tunneled) data.
Need to clear the state back to MSG after having processed all incoming
fragments. Without this, the server got stuck in sending the fragment ACK
even after having received the full message.
Even though we try to disable TLS compression, it is possible that this
cannot be done with all TLS libraries. For example, OpenSSL 0.9.8 does not
seem to have a configuration item for disabling all compression (0.9.9 has
such an option). If compression is used, Phase 2 decryption may end up
producing more data than the input buffer due to compressed data. This
shows up especially with EAP-TNC that uses very compressible data format.
As a workaround, increase the decryption buffer length to (orig_len+500)*3.
This is a hack, but at least it handles most cases. TLS compression should
really be disabled for EAP use of TLS, but since this can show up with
common setups, it is better to handle this case.
If TNC is enabled, PEAPv0 server is now sending out SoH request to initiate
IF-TNCCS-SOH (Microsoft NAP / Statement of Health) handshake. The results
are currently only shown in debug log and they do not affect authentication
or authorization result.
It looks like Microsoft implementation does not match with their
specification as far as PRF+ label usage is concerned.. IPMK|CMK is derived
without null termination on the label, but the label for CSK derivation
must be null terminated.
This allows cryptobinding to be used with PEAPv0 in a way that
interoperates with Windows XP SP3 (RC2) and as such, this functionality is
now enabled as an optional addition to PEAPv0.
Microsoft uses reverse order for MS-MPPE keys in EAP-PEAP when compared to
EAP-FAST derivation of ISK. Swap the keys here to get the correct ISK for
EAP-PEAPv0 cryptobinding. This resolves the cryptobinding interop issue
with WinXP SP3 RC2. However, it looks like MSK derivation does not
interoperate when using cryptobinding, so this code remains disabled for
the time being.
This implementation is complete for PEAPv0 (Microsoft extension), but the
use of cryptobinding is disabled in this version, i.e., this does not
change protocol behavior at all.
Interop tests between hostapd and wpa_supplicant work fine, but there are
some problems in getting hostapd to interoperate with Windows XP SP3 RC2
(peer replies with Result Failure to the attempted cryptobinding). The
implementation will remain disabled until this issue has been resolved.
EAP-PEAP was the only method that used the external eap_tlv.c server
implementation. This worked fine just for the simple protected result
notification, but extending the TLV support for cryptobinding etc. is not
trivial with such separation. With the TLV processing integrated into
eap_peap.c, all the needed information is now available for using
additional TLVs.
Tunneled EAP sequence is now used to perform both the authentication (e.g.,
using EAP-GTC) and TNC validation (EAP-TNC) inside the EAP-FAST tunnel if
TNC has been enabled.
This adds EAP-TNC method and TNCS (IF-IMV and IF-TNCCS) functionality.
There is no integration with EAP-TTLS and EAP-FAST at this point, so this
version is not yet suitable for real use (i.e., EAP-TNC can only be tested
outside a tunnel which is not an allowed configuration for deployment).
However, the basic TNCS functionality is more or less complete and this
version seems to interoperate with wpa_supplicant.
Number of TLVs were processed in groups and these cases were now separated
into more flexible processing of one TLV at the time. wpabuf_concat()
function was added to make it easier to concatenate TLVs. EAP Sequences are
now supported in both server and peer code, but the server side is not
enabled by default.
This allows Phase 2 Identity Request to be skipped if the identity is
already known from PAC-Opaque received in TLS handshake in order to save
one roundtrip from normal authentication.