Besides being undefined behaviour, signed integer overflow can cause
unexpected comparison results. In the case of network_rank_compare(),
a connected network with rank INT_MAX would cause newly inserted
networks with negative rank to be inserted earlier in the ordered
network list. This is reflected in the GetOrderedMethods() DBus method
as can be seen in the following iwctl output:
[iwd]# station wlan0 get-networks
Network name Security Signal
----------------------------------------------------
BEOLAN 8021x **** }
BeoBlue psk *** } all unknown,
UI_Test_Network psk *** } hence assigned
deneb_2G psk *** } negative rank
BEOGUEST open **** }
> titan psk ****
Linksys05274_5GHz_dmt psk ****
Lyngby-4G-4 5GHz psk ****
Using mac80211_hwsim can sometimes result in out of order messages
coming from the kernel. Since mac80211_hwsim immediately sends out
frames and the kernel keeps command responses in a separate queue,
bad scheduling can result in these messages being out of order.
In some cases we receive Auth/Assoc frames before the response to
our original CMD_CONNECT. This causes autotests to fail randomly,
some more often than others.
To fix this we can introduce a small delay into hwsim. Just a 1ms
delay makes the random failures disappear in the tests. This delay
is also makes hwsim more realistic since actual hardware will always
introduce some kind of delay when sending or receiving frames.
mac80211_hwsim now allows setting supported iftypes/ciphers. This patch
enables this support in hwsim. Specific iftypes/ciphers can now be
disabled via the command line when creating a radio:
Disable iftypes:
--iftype-disable station,ap,adhoc,p2p_client,p2p_go,mesh_point
Disable cipher types:
--cipher-disable ccmp,tkip,wep
Since we don't catch all hwsim attribute types in unicast_handler
you see tons of "Unknown attribute type: X" prints. Since this is
not an error, we should only print if the attribute does not exist
in the attribute list.
In mac80211_hwsim each radio is assigned two addresses, the second (addr
1) being used over nl80211. In SendFrame we'd hardcode the mapping of
address 0 to address 1 even though we track all the addresses in radio_info,
so instead use that data to find the radio that has given address 0. Also
if no address 0 matches what was supplied over DBus try to find a matching
address 1.
There are ways userspace can request different addresses when managing
mac80211_hwsim radios and the hardcoded mapping would become wrong.
Added a new method SendFrame() under the radios .Interface
interface. This method takes two byte arrays as parameters,
first is the station address to send the frame to, and the
second is the raw frame data.
Replace is_multicast_addr with util_is_broadcast_address usage.
is_multicast_addr seems to have been wrong, first because we're not
interested in just any multicast address (defined to be same as "group
address"), but rather specifically the broadcast address, as we don't
know of any specific address groups other than broadcast. And also
wrong because the "Individual/Group bit" is the LSB of byte 0, not the
MSB of byte 0 apparently.
Handle NewLink events to detect interface mac address changes. In my
current testing I don't see nl80211 events on address change so it's
best to react to both types of events.
Don't require the full length of a Management MPDU as a condition to
forward the frame, only require data up to the three addresses we need
to know where to forward the frame.
This check was failing with some frames during a deauthentication. We
could possibly forward shorter frames too if needed (send to all
possible recipients.)
Don't handle the hwsim netlink events we use to track radios and
interfaces if we're not in daemon mode. This quiets dbus errors when
using hwsim through the command line.
The name attribute in the NEW RADIO command needs at least 4 bytes for
the attribute header (struct nlattr), all the characters of the name
string and a NUL byte, and up to 3 bytes of alignment padding.
Otherwise, depending on the name length and whether the NO_VIF attribute
was the last, that attribute could end up being dropped and we were
ending up with too many interfaces inside test-runner.
Implement a hwsim wireless medium inside hwsim.c. This doesn't do
anything to the frames it moves around yet, only tries to implement
the same logic that the kernel medium contains.
In daemon mode start a basic passive DBus interface to expose the
information on radios attached to mac80211_hwsim. In this version
interfaces have objects of their own. It might be simpler to only
show them as an array property on the radio object (array of pairs of
string, one string for address, one for name).
Read wiphy addresses from sysfs and perform the wiphy name to wiphy idx
mapping using sysfs. Do this directly on a new radio notification and
stop using new wiphy notifications except for updating the radio names.
Having the wiphy index available synchronously when parsing a new radio
event we store the wiphy index in the radio_info_rec struct directly and
drop struct wiphy_info_rec as there was a 1:1 mapping. With this, and
knowing that all radio_info data is available when new interface
notifications are received, the tracking is simplified because dbus
objects can be created and destroyed within the notification handlers.
We also now store both the wiphy hardware address data and separately
the interface MAC addresses and can use them more appropriately in the
medium implementation.
The kernel expects the radio name attribute to include the string's zero
byte. Things may still work without this if there is padding after the
attribute.
This has been now patched and the zero byte will be optional when that
patch makes its way through different trees.
Add a daemon mode that is entered when no action was specified on the
command line. In this mode hwsim tracks information on radios through
the netlink events. The interface to make use of the information is
added in the next patch.
