This bug has been in here since OWE was written, but a similar bug also
existed in hostapd which allowed the PTK derivation to be identical.
In January 2020 hostapd fixed this bug, which now makes IWD incompatible
when using group 20 or 21.
This patch fixes the bug for IWD, so now OWE should be compatible with
recent hostapd version. This will break compatibility with old hostapd
versions which still have this bug.
If the AP only supports an AKM which requires an auth protocol
CMD_AUTHENTICATE/CMD_ASSOCIATE must be supported or else the
auth protocol cannot be run. All the auth protocols are started
assuming that the card supports these commands, but the support
was never checked when parsing supported commands.
This patch will prevent any fullMAC cards from using
SAE/FILS/OWE. This was the same behavior as before, just an
earlier failure path.
This function was intended to catch socket errors and destroy the group
but it would leak the l_io object if that happened, and if called on
ordinary shutdown it could cause a crash. Since we're now assuming
that the netlink socket operations never fail just remove it.
Only add constants for parsing the Device Information subelement as that
is the main thing we care about in P2P code. And since our own WFD IEs
will likely only need to contain the Device Information subelement, we
don't need builder utilities. We do need iterator utilities because we
may receive WFD IEs with more subelements.
In some cases a P2P peer will ACK our frame but not reply on the first
attempt, and other implementations seem to handle this by going back to
retransmitting the frame at a high rate until it gets ACKed again, at
which point they will again give the peer a longer time to tx the
response frame. Implement the same logic here by adding a
retries_on_ack parameter that takes the number of additional times we
want to restart the normal retransmit counter after we received no
response frame on the first attempt. So passing 0 maintains the
current behaviour, 1 for 1 extra attempt, etc.
In effect we may retransmit a frame about 15 * (retry_on_ack + 1) *
<in-kernel retransmit limit> times. The kernel/driver retransmits a
frame a number of times if there's no ACK (I've seen about 20 normally)
at a high frequency, if that fails we retry the whole process 15 times
inside frame-xchg.c and if we still get no ACK at any point, we give up.
If we do get an ACK, we wait for a response frame and if we don't get
that we will optionally reset the retry counter and restart the whole
thing retry_on_ack times.
In order to support AlwaysRandomizeAddress and AddressOverride, station will
set the desired address into the handshake object. Then, netdev checks if
this was done and will use that address rather than generate one.
This patch adds two new options to a network provisioning file:
AlwaysRandomizeAddress={true,false}
If true, IWD will randomize the MAC address on each connection to this
network. The address does not persists between connections, any new
connection will result in a different MAC.
AddressOverride=<MAC>
If set, the MAC address will be set to <MAC> assuming its a valid MAC
address.
These two options should not be used together, and will only take effect
if [General].AddressRandomization is set to 'network' in the IWD
config file.
If neither of these options are set, and [General].AddressRandomization
is set to 'network', the default behavior remains the same; the MAC
will be generated deterministically on a per-network basis.
Since frame_watch_remove_by_handler only forgets a given function +
user data pointers, and doesn't remove the frame prefixes added in the
kernel, we can avoid later re-registering those prefixes with the
kernel by keeping them in our local watchlist, and only replacing the
handler pointer with a dummy function.
If during WATCHLIST_NOTIFY{,_MATCHES,_NO_ARGS} one of the watch
notify callback triggers a call to watchlist_destroy, give up calling
remaining watches and destroy the watchlist without crashing. This is
useful in frame-xchg.c (P2P use case) where a frame watch may trigger
a move to a new state after receiving a specific frame, and remove one
group of frame watches (including its watchlist) to create a different
group.
For privacy reasons its advantageous to randomize or mask
the MAC address when connecting to networks, especially public
networks.
This patch allows netdev to generate a new MAC address on a
per-network basis. The generated MAC will remain the same when
connecting to the same network. This allows reauthentications
or roaming to work, and not have to fully re-connect (which would
be required if the MAC changed on every connection).
Changing the MAC requires bringing the interface down. This does
lead to potential race conditions with respect to external
processes. There are two potential conditions which are explained
in a TODO comment in this patch.
This API is being added to support per-network MAC address
generation. The MAC is generated based on the network SSID
and the adapters permanent address using HMAC-SHA256. The
SHA digest is then constrained to make it MAC address
compliant.
Generating the MAC address like this will ensure that the
MAC remains the same each time a given SSID is connected to.
Make sure a frame callback is free to call frame_xchg_stop without
causing a crash. Frame callback here means the one that gets
called if our tx frame was ACKed and triggered a respone frame that
matched one of the provided prefixes, within the given time.
All in all a frame callback is allowed to call either
frame_xchg_stop or frame_xchg_startv or neither. Same applies to
the final callback (called when no matching responses received).
Don't crash if the user calls frame_xchg_stop(wdev) from inside the
frame exchange's final callback. That call is going to be redundant but
it's convenient to do this inside a cleanup function for a given wdev
without having to check whether any frame exchange was actually running.
This API was updated to take an extra boolean which will
automatically power up the device while changing the MAC
address. Since this is what IWD does anyways we can avoid
the need for an intermediate callback and go right into
netdev_initial_up_cb.
iwd would fail to connect using EAP-TLS when no CA certificate was
provided as it checked for successful loading of the CA certificate
instead of the client certificate when attempting to load the client
certificate.
The password for EAP-GTC is directly used in an EAP response. The
response buffer is created on the stack so an overly large password
could cause a stack overflow.
mac80211 drivers seem to send the disconnect event which is triggered by
CMD_DISCONNECT prior to the CMD_DISCONNECT response. However, some
drivers, namely brcmfmac, send the response first and then send the
disconnect event. This confused iwd when a connection was immediately
triggered after a disconnection (network switch operation).
Fix this by making sure that connected variable isn't set until the
connect event is actually processed, and ignore disconnect events which
come after CMD_DISCONNECT has alredy succeeded.
For nl80211 sockets other than our main l_genl object use socket io
directly, to avoid creating many instances of l_genl. The only reason
we use multiple sockets is to work around an nl80211 design quirk that
requires closing the socket to unregister management frame watches.
Normally there should not be a need to create multiple sockets in a
program.
Add a little state machine and a related API, to simplify sending out a
frame, receiving the Ack / No-ack status and (if acked) waiting for a
response frame from the target device, one of a list of possible
frame prefixes. The nl80211 API for this makes it complicated
enough that this new API seems to be justified, on top of that there's a
quirk when using the brcmfmac driver where the nl80211 response
(containing the operation's cookie), the Tx Status event and the response
Frame event are received from nl80211 in reverse order (not seen with
other drivers so far), further complicating what should be a pretty
simple task.
Try to better deduplicate the frame watches. Until now we'd check if
we'd already registered a given frame body prefix with the kernel, or a
matching more general prefix (shorter). Now also try to check if we
have already have a watch with the same callback pointer and user_data
value, and:
* an identical or shorter (more general) prefix, in that case ignore
the new watch completely.
* a longer (more specific) prefix, in that case forget the existing
watch.
The use case for this is when we have a single callback for multiple
watches and multiple frame types, and inside that callback we're looking
at the frame body again and matching it to frame types. In that case
we don't want that function to be called multiple times for one frame
event.
In frame_watch_group_remove I forgot to actually match the group to be
removed by both wdev_id and group_id. group_ids are unique only in the
scope of one wdev.
I forgot to actually add new groups being created in
frame_watch_group_get to the watch_groups queue, meaning that we'd
re-create the group every time a new watch was added to the group.
Processing the duplicated TLVs while connecting to a malicious AP may lead
to overflow of the response buffer. This patch ensures that the
duplicated TLVs are not parsed.
The pending wiphy state 'use_default' variable was not set early enough
in some circumstances resulting in weird behavior for blacklisted
drivers. Fix this by adding a manager_wiphy_dump_done callback which
will properly initialize the use_default value.
Fixes: c4b2f10483 ("manager: Handle missing NEW_WIPHY events")
brcmfmac does not allow the removal of the default / primary interface.
So there isn't much point in having iwd attempt this.
Another issue is that brcmfmac _does_ allow the deletion of non-default
interfaces. So starting iwd on a system with a station & ap interface
active can result in iwd attempting to delete all the interfaces. Given
the above, it succeeds in deleting the ap interface but not the station
one. In strange circumstances it might end up thinking that the ap
interface is the 'default' and trying to use it, whereas it was just
successfully removed.
