Commit graph

36 commits

Author SHA1 Message Date
Dedy Lansky
c7f9d44825 FST: Fix search for peer's "other" connection
Upon receiving FST Setup Request from some peer on some interface,
search is made to see if same peer is connected on other interface with
specific band_id. With multiple peers, bug in
fst_group_does_iface_appear_in_other_mbies() caused wrong peer address
to be returned sometimes.

Fix this with a modified, simplified search algorithm of peer's "other"
connection.

Signed-off-by: Dedy Lansky <qca_dlansky@qca.qualcomm.com>
2016-09-08 11:17:45 +03:00
Jouni Malinen
94c4d78ef1 FST: Make fst_action_names static
This is not used outside this file.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2016-06-23 17:48:48 +03:00
Jouni Malinen
82c734c28c FST: Fix byte order of couple of fields on big endian hosts
Couple of fsts_id and llt fields were not properly swapped from host
byte order to little endian byte order used in the frames. Fix this and
use the le32 type to make this more consistent and verifiable with
sparse.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2016-06-23 17:46:40 +03:00
Jouni Malinen
976dfb3237 FST: Make fst_global_deinit() more robust
Verify that fst_global_init() has been called before deinitializing the
global FST context. This makes it a bit easier to handle failure paths
from initialization.

Signed-off-by: Jouni Malinen <j@w1.fi>
2016-06-13 00:37:14 +03:00
Dedy Lansky
cc1af6faed FST: Fix session setup failure with peer without MB IE
Upon receiving FST setup request on old band, the peer is searched on
new band. The assumption is that MB IE from this peer on new band
previously received either in assoc event or in FST setup request.

There are cases in which above assumption doesn't work, peer is not
found and session setup fails. For example:
- STA connects over 11ac. Due to driver limitation, MB IE is not included
in assoc event
- STA connects over 11ad. MB IE included in assoc event.
- FST session established on 11ac band, with AP as initiator. i.e. FST
setup request sent in AP=>STA direction. STA searches for peer's (AP)
MB IE on 11ad band which exists.
- FST switch occur
- FST session established on 11ad band, with STA as initiator. i.e. FST
setup request sent in STA=>AP direction. AP searches for peer's (STA)
MB IE on 11ac band which are absent.

For fixing the above, consider also peers without MB IE as candidates in
the search algorithm.

Signed-off-by: Dedy Lansky <qca_dlansky@qca.qualcomm.com>
2016-03-07 18:04:47 +02:00
Dedy Lansky
0147afa9df FST: Enlarge State Transition Timeout (STT)
STT guards the exchange of FST Action frames with the peer station.
It was observed that sometimes Action frames sending is delayed at
driver/FW layers for few hundreds millisec.

Enlarge the STT to overcome such cases.

Signed-off-by: Dedy Lansky <qca_dlansky@qca.qualcomm.com>
2016-03-03 13:50:03 +02:00
Jouni Malinen
c6e0b4bb86 FST: Get rid of gcc extensions in structure/array initialization
These constructions were causing warnings when build with clang.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2016-01-15 18:40:21 +02:00
Dedy Lansky
071e3bf116 FST: Fix handling of Rx FST Setup Request when session already exists
When we receive FST Setup Request when session already exists, the
following validations take place:
1. we drop the frame if needed according to MAC comparison
2. we drop the frame if the session is "not pending", i.e., if FST
   Setup Response was already exchanged (sent or received).

There are two issues with the above:
1. MAC comparison is relevant only before the Setup Response exchange.
   In other words, Setup Request should not be dropped due to MAC
   comparison after Setup Response has been exchanged.
2. Receiving Setup Request after Setup Response exchange most likely
   means that FST state machine is out of sync with the peer. Dropping
   the Setup Request will not help solve this situation.

The fix is:
1. do MAC comparison only if session is "pending", i.e., Setup Response
   was not yet exchanged.
2. In case Setup Response was already exchanged, reset our session and
   handle the Setup Request as if it arrived when session doesn't exist.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-12-29 18:41:35 +02:00
Anton Nayshtut
b47d05aa45 FST: Make FST peer connection check more permissive in hostapd
Modify the FST peer connection check so it won't skip peers without MB
IEs making it more permissive for peers that didn't provide MB IEs
during association request. This can be helpful, e.g., in cases where a
STA's interface connected before it was added to the FST group. This
allows the AP to receive FST Action frames and initiate session with a
STA via STA's interface that doesn't expose MB IEs.

The adjusted FST protocol is still safe, as it protects itself in many
other ways (checking band info and it's accordance to the interfaces,
Setup IDs, connection states of the interfaces involved, etc.)
effectively avoiding all types of invalid situations.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-11-25 17:30:59 +02:00
Anton Nayshtut
f231b3d816 FST: Fix STA MB IEs creation
FST STA should always expose its MB IEs regardless of its connection
state and whether the connected AP is currently FST-enabled or not.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-11-23 20:36:12 +02:00
Jouni Malinen
84bcb4e7a9 FST: Mark fst_ies buffer const
This buffer is owned by the FST module, so mark it const in the
set_ies() callback to make it clearer which component is responsible for
modifying and freeing this.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-08-03 17:40:30 +03:00
Anton Nayshtut
5e09f24a34 FST: Fix MB IE clearing on detach
This fixes an issue where freed MB IEs buffer memory could potentially
have been accessed after an interface is detached from FST group.
Without this fix, if an interface is detached from FST group, it can use
MB IEs buffer previously set by fst_iface_set_ies(), although the buffer
was released by fst_iface_delete().

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-08-03 17:40:29 +03:00
Jouni Malinen
8f997f044f FST: Make fst_hw_mode_to_band() non-inline function
There is no need for using an inline function for this. Save a bit in
binary size by using a normal function.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 18:45:14 +03:00
Jouni Malinen
f4843c2645 FST: Fix get_peer_mbies interface fetching in multi-group case
The foreach_fst_group() loop needs "break-if-found", not
"continue-if-not-found" to do the search iteration properly. If there
were multiple groups, the previous design could have failed to find the
interface.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 18:45:13 +03:00
Jouni Malinen
1ab51fb595 FST: Merge unreachable error case to another error return
fst_read_next_text_param() is never called with buflen <= 1, so this
separate error path is practically unreachable. Merge it with another
error path to make this a bit more compact.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 18:45:13 +03:00
Jouni Malinen
fa95b7c073 FST: Use more robust interface-find for TEST_REQUEST
It is possible for there to be multiple FST groups, so the hardcoded
mechanism of selecting the first one when sending out an event message
may not be sufficient. Get the interface from the caller, if available,
and if not, go through all groups in search of an interface to send the
event on.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 18:45:13 +03:00
Jouni Malinen
481fa8fb22 FST: Use more robust interface-find for event messages
It is possible for there to be multiple FST groups, so the hardcoded
mechanism of selecting the first one when sending out an event message
may not be sufficient. Get the interface from the caller, if available,
and if not, go through all groups in search of an interface to send the
event on.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 18:12:09 +03:00
Jouni Malinen
55cd405a44 FST: Remove unnecessary fst_attach() already attached check
Now that both hostapd and wpa_supplicant already enforce no duplicate
fst_attach() calls, there is no need for this check within fst_attach().

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 18:12:09 +03:00
Jouni Malinen
fe73b469e8 FST: Fix dialog token wrap-around
Dialog token is only 8 bits and maintaining u32 version of it in struct
fst_group resulted in incorrect wrap-around behavior in
fst_group_assign_dialog_token(). It was possible to assign u8
dialog_token value 0 because of this. Fix this by using u8 variable
consistently.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 18:12:08 +03:00
Jouni Malinen
b019955297 FST: Validate STIE header in FST Setup Request/Response
While this is always supposed to be the first element, check that this
is indeed the case instead of blindly using values from within the
element.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 11:22:21 +03:00
Jouni Malinen
e49f535dc5 FST: Fix Session Transition element length field value
The Element ID and Length subfields are not supposed to be included in
the Length. In addition, both of these subfields needs to be filled in
even for non-zero status code cases.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-26 11:21:58 +03:00
Jouni Malinen
94edea89fd FST: Print reason for ignoring FST Action frame in debug log
This makes it easier to understand why some frames are not processed.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-25 23:20:33 +03:00
Jouni Malinen
9c68b6af97 FST: Fix FST-MANAGER TEST_REQUEST parsing
The space separator between the command and the parameter was not
skipped properly and the first integer ended up being interpreted as 0
in all cases.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-18 19:28:38 +03:00
Jouni Malinen
c715d5c36c FST: Remove unreachable code in fst_session_handle_tear_down()
fst_session_is_in_progress() is already checked as part of
fst_find_session_in_progress() before calling
fst_session_handle_action(). This is the only call path that can reach
fst_session_handle_tear_down() and as such, fst_session_is_in_progress()
cannot return 0 here.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-18 19:06:34 +03:00
Jouni Malinen
a55ebeac26 FST: Remove duplicated dl_list_empty() check befor dl_list_first()
dl_list_first() takes care of this already, so there is no need to do a
separate check here.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-18 17:23:55 +03:00
Jouni Malinen
73664e0985 FST: Use EINVAL more consistently as a negative return value
There was a mix of EINVAL and -EINVAL returns through the FST
implementation. Make this more consistent by always returning -EINVAL in
error cases.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-18 17:23:55 +03:00
Jouni Malinen
a0f04da517 FST: Mark get_mb_ie() return value const
The caller is not expected to free or modify the value since this is
returning a reference to a buffer maintained by the upper layer.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-18 17:23:55 +03:00
Jouni Malinen
74619cc150 FST: Replace print_mb_ies() with wpa_snprintf_hex()
There is no need to add new functions with more or less identical
functionality of an already available helper function.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-18 17:23:55 +03:00
Jouni Malinen
c836aa267e FST: Mark format_session_state_extra() static
This is not used outside fst_ctrl_iface.c.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-07-18 12:40:23 +03:00
Jouni Malinen
6462e7387d FST: Avoid using pointer to mgmt->u.action.u.fst_action
Typecasting &mgmt->u.action.u.fst_action to a struct pointer for various
FST Action frame payloads seemed to be triggering static analyzer
warnings about bounds checking since sizeof(mgmt->u.action.u.fst_action)
== 1 even though that is really a variable length structure. Try to
avoid this by calculating the pointer for the beginning of the frame
instead of variable length struct. (CID 125642)

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-07-17 20:37:15 +03:00
Jouni Malinen
9721b083f4 FST: Remove the IE header len/size macros
These are confusing when the style used with the couple of FST IE checks
differs from the rest of hostapd/wpa_supplicant implementation.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-07-17 19:06:48 +03:00
Jouni Malinen
f5f1cc9307 FST: Clean up fst_group_update_ie()
None of the callers passed in cleaning_up == TRUE, so drop that unused
code path.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-07-17 19:06:48 +03:00
Jouni Malinen
2bb51eddad FST: Move fst_mbie_get_peer_addr() into fst_group.c
There is no need for this function to be an inline function in a header
file since it is used only within fst_group.c.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-07-17 19:06:48 +03:00
Jouni Malinen
be9fbd9b67 FST: Fix FST Action frame length validation
Commit 717333f4e4 ('FST: Add the Fast
Session Transfer (FST) module') performed incorrect frame length
validation for Setup Request (did not remove 24+1 header from
consideration) and did not include payload validation for other FST
Action frames. Fix these by explicitly verifying that the payload of
these frames is sufficiently long before reading the values from there.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-07-17 13:00:17 +03:00
Anton Nayshtut
a8dab08a28 FST: Testing support
This patch introduces infrastructure needed for FST module tests.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-07-16 18:26:16 +03:00
Anton Nayshtut
717333f4e4 FST: Add the Fast Session Transfer (FST) module
Fast Session Transfer (FST) is the transfer of a session from a channel
to another channel in a different frequency band. The term "session"
refers to non-physical layer state information kept by a pair of
stations (STAs) that communicate directly (i.e., excludes forwarding).

The FST is implemented in accordance with IEEE Std 802.11ad-2012.

Definitions

 * FST interface - an interface for which FST functionality is enabled
 * FST group - a bunch of FST interfaces representing single
		multi-band STA
 * FST peer - a multi-band capable STA connected
 * FST module - multi-band operation functionality implemented in
		accordance with IEEE Std 802.11ad-2012 (see 10.32
		Multi-band operation) as a part of hostapd/wpa_supplicant
 * FST manager - an external application that implements custom FST
		related logic, using the FST module's interfaces
		accessible via CLI or D-Bus

This commit introduces only the FST module. Integration of the FST
module into the hostapd/wpa_supplicant and corresponding CLI/D-Bus
interfaces and FST related tests are covered in separate commits.

FST manager application is out of scope of these commits.

As FST aggregates a few interfaces into FST group, the FST module uses
global CLI for both commands and notifications. It also exposes
alternative non-interface based D-Bus subtree for this purposes.

Configuration and Initialization

 * FST functionality can enabled by compilation flag (CONFIG_FST)
 * hostapd/wpa_supplicant controlling multiple interfaces are used for
   FST
 * once enabled by compilation, the FST can be enabled for specific
   interfaces in the configuration files
 * FST interfaces are aggregated in FST groups (fst_group_id config file
   entry), where each FST group:
   - represents one multi-band device
   - should have two or more FST interfaces in it
 * priority (fst_priority config file entry) must be configured for each
   FST interface. FST interface with higher priority is the interface FST
   will always try to switch to. Thus, for example, for the maximal
   throughput, it should be the fastest FST interface in the FST setup.
 * default Link Loss Timeout (LLT) value can be configured for each FST
   interface (fst_llt config file entry). It represents LLT to be used
   by FST when this interface is active.
 * FST interfaces advertise the Multi-band capability by including the
   Multi-band element in the corresponding frames

FST CLI commands:

 * fst list_groups - list FST groups configured.
 * fst list_ifaces - list FST interfaces which belong to specific group
 * fst iface_peers - list Multi-Band STAs connected to specific interface
 * fst list_sessions - list existing FST sessions
 * fst session_get - get FST session info
 * fst session_add - create FST session object
 * fst session_set - set FST session parameters (old_iface, new_iface,
                     peer_addr, llt)
 * fst session_initiate - initiate FST setup
 * fst session_respond - respond to FST setup establishemnt attempt by
                         counterpart
 * fst session_transfer - initiate FST switch
 * fst session_teardown - tear down FST Setup but leave the session object
			  for reuse
 * fst session_remove - remove FST session object

FST CLI notifications:
  * FST-EVENT-PEER - peer state changed (CONNECT/DISCONNECT)
  * FST-EVENT-SESSION - FST session level notification with following
                        sub-events:
     - EVENT_FST_SESSION_STATE - FST session state changed
     - EVENT_FST_ESTABLISHED - previously initiated FST session became
                               established
     - EVENT_FST_SETUP - new FST session object created due to FST session
                         negotiation attempt by counterpart

All the FST CLI commands and notifications are also implemented on D-Bus
for wpa_supplicant.

IEEE 802.11 standard compliance

FST module implements FST setup statemachine in compliance with IEEE
802.11ad (P802.11-REVmc/D3.3), as it described in 10.32 Multi-band
operation (see also Figure 10-34 - States of the FST setup protocol).

Thus, for example, the FST module initiates FST switch automatically
when FST setup becomes established with LLT=0 in accordance with
10.32.2.2 Transitioning between states.

At the moment, FST module only supports non-transparent STA-based FST
(see 10.32.1 General).

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
2015-07-16 18:26:15 +03:00