If the input length is 16 bytes, this means aes_siv_decrypt should
only be verifying the 16 byte SIV and not decrypting any data. If
this is the case, we can skip over the whole AES-CTR portion of
AES-SIV and only verify the SIV.
In eapol_key_handle, 'have_snonce' is checked before decrypting the
key data. For FILS, there will be no snonce so this check can be
skipped if mic_len == 0.
The GTK handshake for FILS uses AES-SIV to encrypt the key data, and
does away with the MIC completely. Now, when finalizing the 2/2 GTK
packet we check the MIC length, and if zero we assume FILS is being
used and we use AES-SIV to encrypt the key data.
For FILS, there is no actual data being encrypted for GTK 2/2 (hence
why the input data length is zero). This results in only the SIV
being generated, which essentially serves the same purpose as a MIC.
FILS does not use a MIC, as well as requires encrypted data on GTK 2/2.
This updates eapol_create_gtk_2_of_2 to pass in extra data to
eapol_create_common, which will reserve room for this encrypted data.
Extra data is only reserved if mic_len == 0.
FILS does not use a MIC in EAPoL frames and also requires encrypted
data on all EAPoL frames. In the common builder the mic_len is now
checked and the flags are set appropriately.
FILS authentication does away with the MIC, so checking for key_mic
in the eapol key frame does not allow FILS to work. Now we pass in
the mic_len to eapol_verify_gtk_1_of_2, and if it is non-zero we can
check that the MIC is present in the frame.
FILS does not require an eapol_sm for authentication, but rekeys
are still performed using the 4-way handshake. Because of this
FILS needs to create a eapol_sm in a 'started' state, but without
calling eapol_start as this will initialize EAP and create handshake
timeouts.
This allows EAPoL to wait for any 4-way packets, and handle them
as rekeys.
ERP (EAP Reauthentication Protocol) allows a station to quickly
reauthenticate using keys from a previous EAP authentication.
This change both implements ERP as well as moves the key cache into
the ERP module.
ERP in its current form is here to only support FILS. ERP is likely not
widespread and there is no easy way to determine if an AP supports ERP
without trying it. Attempting ERP with a non-ERP enabled AP will actually
result in longer connection times since ERP must fail and then full EAP
is done afterwards. For this reason ERP was separated from EAP and a
separate ERP state machine must be created. As it stands now, ERP cannot
be used on its own, only with FILS.
Quick scan uses a set of frequencies associated with the
known networks. This allows to reduce the scan latency.
At this time, the frequency selection follows a very simple
logic by taking all known frequencies from the top 5 most
recently connected networks.
If connection isn't established after the quick scan attempt,
we fall back to the full periodic scan.
Instead of handling NEW_WIPHY events and WIHPY_DUMP events in a similar
fashion, split up the paths to optimize iwd startup time. There's
fundamentally no reason to wait a second (and eat up file-descriptor
resources for timers unnecessarily) when we can simply start an
interface dump right after the wiphy dump.
In case a new wiphy is added in the middle of a wiphy dump, we will
likely get a new wiphy event anyway, in which case a setup_timeout will
be created and we will ignore this phy during the interface dump
processing.
This also optimizes the case of iwd being re-started, in which case
there are no interfaces present.
Separate out the two types of NEW_WIPHY handlers into separate paths and
factor out the common code into a utility function.
Dumps of CMD_NEW_WIPHY can be split up over several messages, while
CMD_NEW_WIPHY events (generated when a new card is plugged in) are
stuffed into a single message.
This also prepares ground for follow-on commits where we will handle the
two types of events differently.
src/netdev.c:netdev_create_from_genl() Skipping duplicate netdev wlp2s0[3]
Aborting (signal 11) [/home/denkenz/iwd/src/iwd]
++++++++ backtrace ++++++++
#0 0x7fc4c7a4e930 in /lib64/libc.so.6
#1 0x40ea13 in netdev_getlink_cb() at src/netdev.c:4654
#2 0x468cab in process_message() at ell/netlink.c:183
#3 0x4690a3 in can_read_data() at ell/netlink.c:289
#4 0x46681d in io_callback() at ell/io.c:126
#5 0x4651cd in l_main_iterate() at ell/main.c:473
#6 0x46530e in l_main_run() at ell/main.c:516
#7 0x465626 in l_main_run_with_signal() at ell/main.c:642
#8 0x403df8 in main() at src/main.c:513
#9 0x7fc4c7a39bde in /lib64/libc.so.6
Mirror netdev.c white/blacklist logic. If either or both the whitelist
and the blacklist are given also fall back to not touching the existing
interface setup on the wiphy.
If we get an error during DEL_INTERFACE or NEW_INTERFACE we may be
dealing with a driver that doesn't implement virtual interfaces or
doesn't implement deleting the default interface. In this case fall
back to using the first usable interface that we've detected on this
wiphy.
There's at least one full-mac driver that doesn't implement the cfg80211
.del_virtual_intf and .add_virtual_intf methods and at least one that
only allows P2P interfaces to be manipulated. mac80211 drivers seem to
at least implement those methods but I didn't check to see if there are
driver where they'd eventually return EOPNOTSUPP.
This is probably the trickiest part in this patchset. I'm introducing a
new logic where instead of using the interfaces that we find present
when a wiphy is detected, which would normally be the one default
interface per wiphy but could be 0 or more than one, we create one
ourselves with the socket owner attribute and use exactly one for
Station, AP and Ad-Hoc modes. When IWD starts we delete all the
interfaces on existing wiphys that we're going to use (as determined by
the wiphy white/blacklists) or freshly hotplugged ones, and only then we
register the interface we're going to use meaning that the wiphy's
limits on the number of concurrent interfaces of each type should be at
0. Otherwise we'd be unlikely to be abe to create the station interface
as most adapters only allow one. After that we ignore any interfaces
that may be created by other processes as we have no use for multiple
station interfaces.
At this point manager.c only keeps local state for wiphys during
the interface setup although when we start adding P2P code we will be
creating and removing interfaces multiple times during the wiphy's
runtime and may need to track it here or in wiphy.c. We do not
specifically check the interface number limits received during the wiphy
dump, if we need to create any interfaces and we're over the driver's
maximum for that specific iftype we'll still attempt it and report error
if it fails.
I tested this and it seems to work with my laptop's intel card and some
USB hotplug adapters.
The latest refactoring ended up assuming that FT related elements would
be handled in netdev_associate_event. However, FullMac cards (that do
not generate netdev_associate_event) could still connect using FT AKMs
and perform the Initial mobility association. In such cases the FTE
element was required but ended up not being set into the handshake.
This caused the handshake to fail during PTK 1_of_4 processing.
Fix this by making sure that FTE + related info is set into the
handshake, albeit with a lower sanity checking level since the
elements have been processed by the firmware already.
Note that it is currently impossible for actual FTs to be performed on
FullMac cards, so the extra logic and sanity checking to handle these
can be skipped.
Add functionality to read and parse the known frequencies
from permanent storage on start of the service. On service
shutdown, we sync the known frequencies back to the permanent
storage.
Each known network (previously connected) will have a set
of known frequencies associated with it, e.g. a set of
frequencies from all BSSs observed. The list of known
frequencies is sorted with the most recently observed
frequency in the head.
Previously, the scan results were disregarded once the new
ones were available. To enable the scan scenarios where the
new scan results are delivered in parts, we introduce a
concept of aging BSSs and will remove them based on
retention time.
Add manager.c, a new file where the wiphy and interface creation/removal
will be handled and interface use policies will be implemented. Since
not all kernel-side nl80211 interfaces are tied to kernel-side netdevs,
netdev.c can't manage all of the interfaces that we will be using, so
the logic is being moved to a common place where all interfaces on a
wiphy will be managed according to the policy, device support for things
like P2P and user enabling/disabling/connecting with P2P which require
interfaces to be dynamically added and removed.
Add wiphy_create, wiphy_update_from_genl and wiphy_destroy that together
will let a new file command the wiphy creation, updates and deletion
with the same functionality the current config notification handler
implements in wiphy.c.
As mentioned in code comments the name is NUL-terminated so there's no
need to return the length path, which was ignored in some occasions
anyway. Consistently treat it as NUL-terminated but also validate.
Make netdev_create_from_genl public and change signature to return the
created netdev or NULL. Also add netdev_destroy that destroys and
unregisters the created netdevs. Both will be used to move the
whole interface management to a new file.
The handshake_state only holds a single AKM value. FILS depends on the AP
supporting EAP as well as FILS. The first time IWD connects, it will do a
full EAP auth. Subsequent connections (assuming FILS is supported) will use
FILS. But if the AP does not support FILS there is no reason to cache the
ERP keys.
This adds the supp_fils to the handshake_state. Now, station.c can set this
flag while building the handshake. This flag can later be checked when
caching the ERP keys.
This allows IWD to cache ERP keys after a full EAP run. Caching
allows IWD to quickly connect to the network later on using ERP or
FILS.
The cache will contain the EAP Identity, Session ID, EMSK, SSID and
optionally the ERP domain. For the time being, the cache entry
lifetimes are hard coded to 24 hours. Eventually the cache should
be written to disk to allow ERP/FILS to work after a reboot or
IWD restart.
mschaputil already had similar functionality, but ERP will need this
as well. These two functions will also handle identities with either
'@' or '\' to separate the user and domain.
Many operations performed during an error in load_settings were the same
as the ones performed when freeing the eap object. Add eap_free_common
to unify these.
EAP identites are recommended to follow RFC 4282 (The Network Access
Identifier). This RFC recommends a maximum NAI length of 253 octets.
It also mentions that RADIUS is only able to support NAIs of 253
octets.
Because of this, IWD should not allow EAP identities larger than 253
bytes. This change adds a check in eap_load_settings to verify the
identity does not exceed this limit.
The associate event is only important for OWE and FT. If neither of
these conditions (or FT initial association) are happening we do
not need to continue further processing the associate event.
802.11 mandates that IEs inside management frames are presented in a
given order. However, in the real world, many APs seem to ignore the
rules and send their IEs in seemingly arbitrary order, especially when
it comes to VENDOR tags. Change this function to no longer be strict in
enforcing the order.
Also, drop checking of rules specific to Probe Responses. These will
have to be handled separately (most likely by the AP module) since
802.11-2016, Section 11.1.4.3.5 essentially allows just about anything.
In netdev_associate_event the ignore_connect_event was getting set true,
but afterwards there were still potential failure paths. Now, once in
assoc_failed we explicitly set ignore_connect_event to false so the
the failure can be handled properly inside netdev_connect_event
The list of PSK/8021x AKM's in security_determine was getting long,
and difficult to keep under 80 characters. This moves them all into
two new macros, AKM_IS_PSK/AKM_IS_8021X.
It was assumed that the hunt-and-peck loop was guarenteed to find
a PWE. This was incorrect in terms of kernel support. If a system
does not have support for AF_ALG or runs out of file descriptors
the KDFs may fail. The loop continued to run if found == false,
which is also incorrect because we want to stop after 20 iterations
regarless of success.
This changes the loop to a for loop so it will always exit after
the set number of iterations.
CC src/scan.o
src/scan.c: In function ‘scan_bss_compute_rank’:
src/scan.c:1048:4: warning: this decimal constant is unsigned only in ISO C90
factor = factor * data_rate / 2340000000 +
The auto-connect state will now consist of the two phases:
STATION_STATE_AUTOCONNECT_QUICK and STATION_STATE_AUTOCONNECT_FULL.
The auto-connect will always start with STATION_STATE_AUTOCONNECT_QUICK
and then transition into STATION_STATE_AUTOCONNECT_FULL if no
connection has been established. During STATION_STATE_AUTOCONNECT_QUICK
phase we take advantage of the wireless scans with the limited number
of channels on which the known networks have been observed before.
This approach allows to shorten the time required for the network
sweeps, therefore decreases the connection latency if the connection
is possible. Thereafter, if no connection has been established after
the first phase we transition into STATION_STATE_AUTOCONNECT_FULL and
do the periodic scan just like we did before the split in
STATION_STATE_AUTOCONNECT state.
For simplicity 160Mhz and 80+80Mhz were grouped together when
parsing the VHT capabilities, but the 80+80 bits were left in
vht_widht_map. This could cause an overflow when getting the
width map.
wiphy_select_akm will now check if BIP is supported, and if MFPR is
set in the scan_bss before returning either SAE AKMs. This will allow
fallback to another PSK AKM (e.g. hybrid APs) if any of the requirements
are not met.
Replace existing uses of memset to clear secrets with explicit_bzero to
make sure it doesn't get optimized away. This has some side effects as
documented in gcc docs but is still recommended.
In eap_secret_info_free make sure we clear both strings in the case of
EAP_SECRET_REMOTE_USER_PASSWORD secrets.
Environments with several AP's, all at low signal strength may
want to lower the roaming RSSI threshold to prevent IWD from
roaming excessively. This adds an option 'roam_rssi_threshold',
which is still defaulted to -70.
Also printing keys with l_debug conditional on an environment variable
as someone wanting debug logs, or leaving debug on accidentally, does
not necessarily want the keys in the logs and in memory.
At some point the connect command builder was modified, and the
control port over NL80211 check was moved to inside if (is_rsn).
For WPS, no supplicant_ie was set, so CONTROL_PORT_OVER_NL80211
was never set into CMD_CONNECT. This caused IWD to expect WPS
frames over netlink, but the kernel was sending them over the
legacy route.
This commit hardens the iwd.service.in template file for systemd
services. The following is a short explanation for each added directive:
+PrivateTmp=true
If true, sets up a new file system namespace for the executed processes
and mounts private /tmp and /var/tmp directories inside it that is not
shared by processes outside of the namespace.
+NoNewPrivileges=true
If true, ensures that the service process and all its children can never
gain new privileges through execve() (e.g. via setuid or setgid bits, or
filesystem capabilities).
+PrivateDevices=true
If true, sets up a new /dev mount for the executed processes and only
adds API pseudo devices such as /dev/null, /dev/zero or /dev/random (as
well as the pseudo TTY subsystem) to it, but no physical devices such as
/dev/sda, system memory /dev/mem, system ports /dev/port and others.
+ProtectHome=yes
If true, the directories /home, /root and /run/user are made
inaccessible and empty for processes invoked by this unit.
+ProtectSystem=strict
If set to "strict" the entire file system hierarchy is mounted
read-only, except for the API file system subtrees /dev, /proc and /sys
(protect these directories using PrivateDevices=,
ProtectKernelTunables=, ProtectControlGroups=).
+ReadWritePaths=/var/lib/iwd/
Sets up a new file system namespace for executed processes. These
options may be used to limit access a process might have to the file
system hierarchy. Each setting takes a space-separated list of paths
relative to the host's root directory (i.e. the system running the
service manager). Note that if paths contain symlinks, they are resolved
relative to the root directory set with RootDirectory=/RootImage=.
Paths listed in ReadWritePaths= are accessible from within
the namespace with the same access modes as from outside of
it.
+ProtectControlGroups=yes
If true, the Linux Control Groups (cgroups(7)) hierarchies accessible
through /sys/fs/cgroup will be made read-only to all processes of the
unit.
+ProtectKernelModules=yes
If true, explicit module loading will be denied. This allows module
load and unload operations to be turned off on modular kernels.
For further explanation to all directives see `man systemd.directives`
Hostapd has now been updated to include the group number when rejecting
the connection with UNSUPP_FINITE_CYCLIC_GROUP. We still need the existing
len == 0 check because old hostapd versions will still behave this way.
The single-use password is apparently sent in plaintext over the network
but at least try to prevent it from staying in the memory until we know
it's been used.
station.c generates the IEs we will need to use for the
Authenticate/Associate and EAPoL frames and sets them into the
handshake_state object. However the driver may modify some of them
during CMD_CONNECT and we need to use those update values so the AP
isn't confused about differing IEs in diffent frames from us.
Specifically the "wl" driver seems to do this at least for the RSN IE.
The KDF function processes data in 32 byte chunks so for groups which
primes are not divisible by 32 bytes, you will get a buffer overflow
when copying the last chunk of data.
Now l_checksum_get_digest is limited to the bytes remaining in the
buffer, or 32, whichever is the smallest.
Since eapol_encrypt_key_data already calculates the key data length and
encodes it into the key frame, we can just return this length and avoid
having to obtain it again from the frame.
Similar to SAE, EAP-PWD derives an ECC point (PWE). It is possible
for information to be gathered from the timing of this derivation,
which could be used to to recover the password.
This change adapts EAP-PWD to use the same mitigation technique as
SAE where we continue to derive ECC points even after we have found
a valid point. This derivation loop continues for a set number of
iterations (20 in this case), so anyone timing it will always see
the same timings for every run of the protocol.
This is not used by any of the scan notify callback implementations and
for P2P we're going to need to scan on an interface without an ifindex
so without this the other changes should be mostly contained in scan.
Also add a mask parameter to wiphy_get_supported_iftypes to make sure
the SupportedModes property only contains the values that can be used
as Device.Mode.
dbus_iftype_to_string returns NULL for unknown iftypes, the strdup will
also return NULL and ret[i] will be assigned a NULL. As a result
the l_strjoinv will not print the known iftypes that might have come
after that and will the l_strfreev will leak the strduped strings.
sc->state would get set when the TRIGGERED event arrived or when the
triggered callback for our own SCAN_TRIGGER command is received.
However it would not get reset to NOT_RUNNING when the NEW_SCAN_RESULTS
event is received, instead we'd first request the results with GET_SCAN
and only reset sc->state when that returns. If during that command a
new scan gets triggered, the GET_SCAN callback would still reset
sc->state and clobber the value set by the new scan.
To fix that repurpose sc->state to only track that period from the
TRIGGERED signal to the NEW_SCAN_RESULTS signal. sc->triggered can be
used to check if we're still waiting for the GET_SCAN command and
sc->start_cmd_id to check if we're waiting for the scan to get
triggered, so one of these three variables will now always indicate if
a scan is in progress.
We can crash if we abort the connection, but the connect command has
already gone through. In this case we will get a sequence of
authenticate_event, associate_event, connect_event. The first and last
events don't crash since they check whether netdev->connected is true.
However, this causes an annoying warning to be printed.
Fix this by introducing an 'aborting' flag and ignore all connection
related events if it is set.
++++++++ backtrace ++++++++
Now that the OWE failure/retry is handled in netdev, we can catch
all associate error status' inside owe_rx_associate rather than only
catching UNSUPP_FINITE_CYCLIC_GROUP.
Apart from OWE, the association event was disregarded and all association
processing was done in netdev_connect_event. This led to
netdev_connect_event having to handle all the logic of both success and
failure, as well as parsing the association for FT and OWE. Also, without
checking the status code in the associate frame there is the potential
for the kernel to think we are connected even if association failed
(e.g. rogue AP).
This change introduces two flags into netdev, expect_connect_failure and
ignore_connect_event. All the FT processing that was once in
netdev_connect_event has now been moved into netdev_associate_event, as
well as non-FT associate frame processing. The connect event now only
handles failure cases for soft/half MAC cards.
Note: Since fullmac cards rely on the connect event, the eapol_start
and netdev_connect_ok were left in netdev_connect_event. Since neither
auth/assoc events come in on fullmac we shouldn't have any conflict with
the new flags.
Once a connection has completed association, EAPoL is started from
netdev_associate_event (if required) and the ignore_connect_event flag can
be set. This will bypass the connect event.
If a connection has failed during association for whatever reason, we can
set expect_connect_failure, the netdev reason, and the MPDU status code.
This allows netdev_connect_event to both handle the error, and, if required,
send a deauth telling the kernel that we have failed (protecting against the
rogue AP situation).
OWE processing can be completely taken care of inside
netdev_authenticate_event and netdev_associate_event. This removes
the need for OWE specific checks inside netdev_connect_event. We can
now return early out of the connect event if OWE is in progress.
Several Auth/Assoc failure status codes indicate that the connection
failed for reasons such as bandwidth issues, poor channel conditions
etc. These conditions should not result in the BSS being blacklisted
since its likely only a temporary issue and the AP is not actually
"broken" per-se.
This adds support in station.c to temporarily blacklist these BSS's
on a per-network basis. After the connection has completed we clear
out these blacklist entries.
Certain error conditions require that a BSS be blacklisted only for
the duration of the current connection. The existing blacklist
does not allow for this, and since this blacklist is shared between
all interfaces it doesnt make sense to use it for this purpose.
Instead, each network object can contain its own blacklist of
scan_bss elements. New elements can be added with network_blacklist_add.
The blacklist is cleared when the connection completes, either
successfully or not.
Now inside network_bss_select both the per-network blacklist as well as
the global blacklist will be checked before returning a BSS.
Several netdev events benefit from including event data in the callback.
This is similar to how the connect callback works as well. The content
of the event data is documented in netdev.h (netdev_event_func_t).
By including event data for the two disconnect events, we can pass the
reason code to better handle the failure in station.c. Now, inside
station_disconnect_event, we still check if there is a pending connection,
and if so we can call the connect callback directly with HANDSHAKE_FAILED.
Doing it this way unifies the code path into a single switch statment to
handle all failures.
In addition, we pass the RSSI level index as event data to
RSSI_LEVEL_NOTIFY. This removes the need for a getter to be exposed in
netdev.h.
On successful send, scan_send_start(..) used to set msg to NULL,
therefore the further management of the command by the caller was
impossible. This patch removes wrapper around l_genl_family_send()
and lets the callers to take responsibility for the command.
This change cleans up the mess of status vs reason codes. The two
types of codes have already been separated into different enumerations,
but netdev was still treating them the same (with last_status_code).
A new 'event_data' argument was added to the connect callback, which
has a different meaning depending on the result of the connection
(described inside netdev.h, netdev_connect_cb_t). This allows for the
removal of netdev_get_last_status_code since the status or reason
code is now passed via event_data.
Inside the netdev object last_status_code was renamed to last_code, for
the purpose of storing either status or reason. This is only used when
a disconnect needs to be emitted before failing the connection. In all
other cases we just pass the code directly into the connect_cb and do
not store it.
All ocurrences of netdev_connect_failed were updated to use the proper
code depending on the netdev result. Most of these simply changed from
REASON_CODE_UNSPECIFIED to STATUS_CODE_UNSPECIFIED. This was simply for
consistency (both codes have the same value).
netdev_[authenticate|associate]_event's were updated to parse the
status code and, if present, use that if their was a failure rather
than defaulting to UNSPECIFIED.
Even though .check_settings in our EAP method implementations does the
settings validation, .load_settings also has minimum sanity checks to
rule out segfaults if the settings have changed since the last
.check_settings call.
If OWE fails in association there is no reason to send a disconnect
since its already known that we failed. Instead we can directly
call netdev_connect_failed
Instead of sending a reason_code to netdev_setting_keys_failed, make it
take an errno (negative) instead. Since key setting failures are
entirely a system / software issue, and not a protocol issue, it makes
no sense to use a protocol error code.
Some users may need their own control over 2.4/5GHz preference. This
adds a new user option, 'rank_5g_factor', which allows users to increase
or decrease their 5G preference.
This adds support for parsing the VHT IE, which allows a BSS supporting
VHT (80211ac) to be ranked higher than a BSS supporting only HT/basic
rates. Now, with basic/HT/VHT parsing we can calculate the theoretical
maximum data rate for all three and rank the BSS based on that.
This adds HT IE parsing and data rate calculation for HT (80211n)
rates. Now, a BSS supporting HT rates will be ranked higher than
a basic rate BSS, assuming the RSSI is at an acceptable level.
The spec dictates RSSI thresholds for different modulation schemes, which
correlate to different data rates. Until now were were ranking a BSS with
only looking at its advertised data rate, which may not even be possible
if the RSSI does not meet the threshold.
Now, RSSI is taken into consideration and the data rate returned from
parsing (Ext) Supported Rates IE(s) will reflect that.
All over the place we do "ie[1] + 2" for getting the IE length. It
is much clearer to use a macro to do this. The macro also checks
for NULL, and returns zero in this case.
Supported rates will soon be parsed along with HT/VHT capabilities
to determine the best data rate. This will remove the need for the
supported_rates uintset element in scan_bss, as well as the single
API to only parse the supported rates IE. AP still does rely on
this though (since it only supports basic rates), so the parsing
function was moved into ap.c.
In the methods' check_settings do a more complete early check for
possible certificate / private key misconfiguration, including check
that the certificate and the private key are always present or absent
together and that they actually match each other. Do this by encrypting
and decrypting a small buffer because we have no better API for that.
A method's .check_settings method checks for inconsistent setting files
and prints readable errors so there's no need to do that again in
.load_settings, although at some point after removing the duplicate
error messages from the load_settings methods we agreed to keep minimum
checks that could cause a crash e.g. in a corner case like when the
setting file got modified between the check_settings and the
load_settings call. Some error messages have been re-added to
load_settings after that (e.g. in
bb4e1ebd4f) but they're incomplete and not
useful so remove them.
Previously, the storage dir has only been created after a successful
network connection, causing removal of Known Network interface from
Dbus and failure to register dir watcher until daemon is restarted.
A length check was still assuming the 256 bit ECC group. This
was updated to scale with the group. The commit buffer was also
not properly sized. This was changed to allow for the largest
ECC group supported.
SAE was hardcoded to work only with group 19. This change fixes up the
hard coded lengths to allow it to work with group 20 since ELL supports
it. There was also good amount of logic added to support negotiating
groups. Before, since we only supported group 19, we would just reject
the connection to an AP unless it only supported group 19.
This did lead to a discovery of a potential bug in hostapd, which was
worked around in SAE in order to properly support group negotiation.
If an AP receives a commit request with a group it does not support it
should reject the authentication with code 77. According to the spec
it should also include the group number which it is rejecting. This is
not the case with hostapd. To fix this we needed to special case a
length check where we would otherwise fail the connection.
Most of this work was already done after moving ECC into ELL, but
there were still a few places where the 256-bit group was assumed.
This allows the 384-bit group to be used, and theoretically any
other group added to ELL in the future.
If we have a BSS list where all BSS's have been blacklisted we still
need a way to force a connection to that network, instead of having
to wait for the blacklist entry to expire. network_bss_select now
takes a boolean 'fallback_to_blacklist' which causes the selection
to still return a connectable BSS even if the entire list was
blacklisted.
In most cases this is set to true, as these cases are initiated by
DBus calls. The only case where this is not true is inside
station_try_next_bss, where we do want to honor the blacklist.
This both prevents an explicit connect call (where all BSS's are
blacklisted) from trying all the blacklisted BSS's, as well as the
autoconnect case where we simply should not try to connect if all
the BSS's are blacklisted.
There are is some implied behavior here that may not be obvious:
On an explicit DBus connect call IWD will attempt to connect to
any non-blacklisted BSS found under the network. If unsuccessful,
the current BSS will be blacklisted and IWD will try the next
in the list. This will repeat until all BSS's are blacklisted,
and in this case the connect call will fail.
If a connect is tried again when all BSS's are blacklisted IWD
will attempt to connect to the first connectable blacklisted
BSS, and if this fails the connect call will fail. No more
connection attempts will happen until the next DBus call.
If IWD fails to connect to a BSS we can attempt to connect to a different
BSS under the same network and blacklist the first BSS. In the case of an
incorrect PSK (MMPDU code 2 or 23) we will still fail the connection.
station_connect_cb was refactored to better handle the dbus case. Now the
netdev result switch statement is handled before deciding whether to send
a dbus reply. This allows for both cases where we are trying to connect
to the next BSS in autoconnect, as well as in the dbus case.
This makes __station_connect_network even less intelligent by JUST
making it connect to a network, without any state changes. This makes
the rekey logic much cleaner.
We were also changing dbus properties when setting the state to
CONNECTING, so those dbus property change calls were moved into
station_enter_state.
A new driver extended feature bit was added signifying if the driver
supports PTK replacement/rekeying. During a connect, netdev checks
for the driver feature and sets the handshakes 'no_rekey' flag
accordingly.
At some point the AP will decide to rekey which is handled inside
eapol. If no_rekey is unset we rekey as normal and the connection
remains open. If we have set no_rekey eapol will emit
HANDSHAKE_EVENT_REKEY_FAILED, which is now caught inside station. If
this happens our only choice is to fully disconnect and reconnect.
If we receive handshake message 1/4 after we are already connected
the AP is attempting to rekey. This may not be allowed and if not
we do not process the rekey and emit HANDSHAKE_EVENT_REKEY_FAILED
so any listeners can handle accordingly.
The AP structure was getting cleaned up twice. When the DBus stop method came
in we do AP_STOP on nl80211. In this callback the AP was getting freed in
ap_reset. Also when the DBus interface was cleaned up it triggered ap_reset.
Since ap->started gets set to false in ap_reset, we now check this and bail
out if the AP is already stopped.
Fixes:
++++++++ backtrace ++++++++
0 0x7f099c11ef20 in /lib/x86_64-linux-gnu/libc.so.6
1 0x43fed0 in l_queue_foreach() at ell/queue.c:441 (discriminator 3)
2 0x423a6c in ap_reset() at src/ap.c:140
3 0x423b69 in ap_free() at src/ap.c:162
4 0x44ee86 in interface_instance_free() at ell/dbus-service.c:513
5 0x451730 in _dbus_object_tree_remove_interface() at ell/dbus-service.c:1650
6 0x405c07 in netdev_newlink_notify() at src/netdev.c:4449 (discriminator 9)
7 0x440775 in l_hashmap_foreach() at ell/hashmap.c:534
8 0x4455d3 in process_broadcast() at ell/netlink.c:158
9 0x4439b3 in io_callback() at ell/io.c:126
10 0x442c4e in l_main_iterate() at ell/main.c:473
11 0x442d1c in l_main_run() at ell/main.c:516
12 0x442f2b in l_main_run_with_signal() at ell/main.c:644
13 0x403ab3 in main() at src/main.c:504
14 0x7f099c101b97 in /lib/x86_64-linux-gnu/libc.so.6
+++++++++++++++++++++++++++
This will allow for blacklisting a BSS if the connection fails. The
actual blacklist module is simple and must be driven by station. All
it does is add BSS addresses, a timestamp, and a timeout to a queue.
Entries can also be removed, or checked if they exist. The blacklist
timeout is configuratble in main.conf, as well as the blacklist
timeout multiplier and maximum timeout. The multiplier is used after
a blacklisted BSS timeout expires but we still fail to connect on the
next connection attempt. We multiply the current timeout by the
multiplier so the BSS remains in the blacklist for a larger growing
amount of time until it reaches the maximum (24 hours by default).
Soon BSS blacklisting will be added, and in order to properly decide if
a BSS should be blacklisted we need the status code on a failed
connection. This change stores the status code when there is a failure
in netdev and adds a getter to retrieve later. In many cases we have
the actual status code from the AP, but in some corner cases its not
obtainable (e.g. an error sending an NL80211 command) in which case we
just default to MMPDU_REASON_CODE_UNSPECIFIED.
Rather than continue with the pattern of setting netdev->result and
now netdev->last_status_code, the netdev_connect_failed function was
redefined so its no longer used as both a NL80211 callback and called
directly. Instead a new function was added, netdev_disconnect_cb which
just calls netdev_connect_failed. netdev_disconnect_cb should not be
used for all the NL80211 disconnect commands. Now netdev_connect_failed
takes both a result and status code which it sets in the netdev object.
In the case where we were using netdev_connect_failed as a callback we
still need to set the result and last_status_code but at least this is
better than having to set those in all cases.
Remove an unneeded buffer and its memcpy, remove the now unneeded use of
l_checksum_digest_length and use l_checksum_reset instead of creating a
new l_checksum for each chunk.
ELL ECC supports group 20 (P384) so OWE can also support it. This also
adds group negotiation, where OWE can choose a different group than the
default if the AP requests it.
A check needed to be added in netdev in order for the negotiation to work.
The RFC says that if a group is not supported association should be rejected
with code 77 (unsupported finite cyclic group) and association should be
started again. This rejection was causing a connect event to be emitted by
the kernel (in addition to an associate event) which would result in netdev
terminating the connection, which we didn't want. Since OWE receives the
rejected associate event it can intelligently decide whether it really wants
to terminate (out of supported groups) or try the next available group.
This also utilizes the new MIC/KEK/KCK length changes, since OWE dictates
the lengths of those keys.
Rather than hard coding to SHA256, we can pass in l_checksum_type
and use that SHA. This will allow for OWE/SAE/PWD to support more
curves that use different SHA algorithms for hashing.
OWE defines KEK/KCK lengths depending on group. This change adds a
case into handshake_get_key_sizes. With OWE we can determine the
key lengths based on the PMK length in the handshake.
In preparation for OWE supporting multiple groups eapol needed some
additional cases to handle the OWE AKM since OWE dictates the KEK,
KCK and MIC key lengths (depending on group).
Right now the PMK is hard coded to 32 bytes, which works for the vast
majority of cases. The only outlier is OWE which can generate a PMK
of 32, 48 or 64 bytes depending on the ECC group used. The PMK length
is already stored in the handshake, so now we can just pass that to
crypto_derive_pairwise_ptk
The crypto_ptk was hard coded for 16 byte KCK/KEK. Depending on the
AKM these can be up to 32 bytes. This changes completely removes the
crypto_ptk struct and adds getters to the handshake object for the
kck and kek. Like before the PTK is derived into a continuous buffer,
and the kck/kek getters take care of returning the proper key offset
depending on AKM.
To allow for larger than 16 byte keys aes_unwrap needed to be
modified to take the kek length.
The MIC length was hard coded to 16 bytes everywhere, and since several
AKMs require larger MIC's (24/32) this needed to change. The main issue
was that the MIC was hard coded to 16 bytes inside eapol_key. Instead
of doing this, the MIC, key_data_length, and key_data elements were all
bundled into key_data[0]. In order to retrieve the MIC, key_data_len,
or key_data several macros were introduced which account for the MIC
length provided.
A consequence of this is that all the verify functions inside eapol now
require the MIC length as a parameter because without it they cannot
determine the byte offset of key_data or key_data_length.
The MIC length for a given handshake is set inside the SM when starting
EAPoL. This length is determined by the AKM for the handshake.
Non-802.11 AKMs can define their own key lengths. Currently only OWE does
this, and the MIC/KEK/KCK lengths will be determined by the PMK length so
we need to save it.
Make sure we don't pass NULLs to memcmp or l_memdup when the prefix
buffer is NULL. There's no point having callers pass dummy buffers if
they need to watch frames independent of the frame data.
Start using l_key_generate_dh_private and l_key_validate_dh_payload to
check for the disallowed corner case values in the DH private/public
values generated/received.
Some of the EAP methods don't require a clear-text identity to
be sent with the Identity Response packet. The mandatory identity
filed has resulted in unnecessary transmission of the garbage
values. This patch makes the Identity field to be optional and
shift responsibility to ensure its existence to the individual
methods if the field is required. All necessary identity checks
have been previously propagated to individual methods.
If a network is being forgotten, then make sure to reset connected_time.
Otherwise the rank logic thinks that the network is known which can
result in network_find_rank_index returning -1.
Found by sanitizer:
src/network.c:1329:23: runtime error: index -1 out of bounds for type
'double [64]'
==25412==ERROR: AddressSanitizer: global-buffer-overflow on address 0x000000421ab0 at pc 0x000000402faf bp 0x7fffffffdb00 sp 0x7fffffffdaf0
READ of size 4 at 0x000000421ab0 thread T0
#0 0x402fae in validate_mgmt_ies src/mpdu.c:128
#1 0x403ce8 in validate_probe_request_mmpdu src/mpdu.c:370
#2 0x404ef2 in validate_mgmt_mpdu src/mpdu.c:662
#3 0x405166 in mpdu_validate src/mpdu.c:706
#4 0x402529 in ie_order_test unit/test-mpdu.c:156
#5 0x418f49 in l_test_run ell/test.c:83
#6 0x402715 in main unit/test-mpdu.c:171
#7 0x7ffff5d43ed9 in __libc_start_main (/lib64/libc.so.6+0x20ed9)
#8 0x4019a9 in _start (/home/denkenz/iwd-master/unit/test-mpdu+0x4019a9)
This fixes the valgrind warning:
==14804== Conditional jump or move depends on uninitialised value(s)
==14804== at 0x402E56: sae_is_quadradic_residue (sae.c:218)
==14804== by 0x402E56: sae_compute_pwe (sae.c:272)
==14804== by 0x402E56: sae_build_commit (sae.c:333)
==14804== by 0x402E56: sae_send_commit (sae.c:591)
==14804== by 0x401CC3: test_confirm_after_accept (test-sae.c:454)
==14804== by 0x408A28: l_test_run (test.c:83)
==14804== by 0x401427: main (test-sae.c:566)
The return from l_ecc_point_from_data was not being checked for NULL,
which would cause a segfault if the peer sent an invalid point.
This adds a check and fails the protocol if p_element is NULL, as the
spec defines.
src/eap-ttls.c:766:50: error: ‘Password’ directive output may be truncated writing 8 bytes into a region of size between 1 and 72 [-Werror=format-truncation=]
snprintf(password_key, sizeof(password_key), "%sPassword", prefix);
^~~~~~~~
In file included from /usr/include/stdio.h:862,
from src/eap-ttls.c:28:
/usr/include/bits/stdio2.h:64:10: note: ‘__builtin___snprintf_chk’ output between 9 and 80 bytes into a destination of size 72
return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
__bos (__s), __fmt, __va_arg_pack ());
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Stop using l_pem_load_certificate which has been removed from ell, use
the same functions to load certificate files to validate them as those
used by the TLS implementation itself.
Check that the TLS logic has verified the server is trusted by the CA if
one was configured. This is more of an assert as ell intentionally only
allows empty certificate chains from the peer in server mode (if a CA
certficate is set) although this could be made configurable.
This should not change the behaviour except for fixing a rare crash
due to scan_cancel not working correctly when cancelling the first scan
request in the queue while a periodic scan was running, and potentially
other corner cases. To be able to better distinguish between a periodic
scan in progress and a scan request in progress add a sc->current_sr
field that points either at a scan request or is NULL when a periodic
scan is in ongoing. Move the triggered flag from scan_request and
scan_preiodic directly to scan_context so it's there together with
start_cmd_id. Hopefully make scan_cancel simpler/clearer.
Note sc->state and sc->triggered have similar semantics so one of them
may be easily removed. Also the wiphy_id parameter to the scan callback
is rather useless, note I temporarily pass 0 as the value on error but
perhaps it should be dropped.
In the name of failing earlier try to generate the PSK from the
passphrase as soon as we receive the passphrase or read it from the
file, mainly to validate it has the right number of characters.
The passphrase length currently gets validates inside
crypto_psk_from_passphrase which will be called when we receive a new
passphrase from the agent or when the config file has no PSK in it. We
do not do this when there's already both the PSK and the passphrase
available in the settings -- we can add that separately if needed.
The main difference with this is that scan_context removal will also
trigger the .destroy calls. Normally there won't be any requests left
during scan_context but if there were any we should call destroy on
them.
If we haven't sent a PMKID, and we're not running EAP, then ignore
whatever PMKID the AP sends us. Frequently the APs send us garbage in
this field. For PSK and related AKMs, if the PMK is wrong, then we
simply fail to generate a proper MIC and the handshake would fail at a
later stage anyway.
Fix incorrect usage of the caller’s scan triggered callback.
In case of a failure, destroy scan request and notify caller
about the issue by returning zero scan id instead of calling
callers’ scan triggered callback with an error code.
Using backtrace() is of no use when building with PIE (which most
distro compilers do by default) and prevents catching the coredump
for later retracing, which is needed since distros usually don't
install debug symbols by default either.
This patch thus only enables backtrace() when --enable-maintainer-mode
is passed and also tries to explicitly disable PIE.
ECDH was expecting the private key in LE, but the public key in BE byte ordering.
For consistency the ECDH now expect all inputs in LE byte ordering. It is up to
the caller to order the bytes appropriately.
This required adding some ecc_native2be/be2native calls in OWE
The changes to station.c are minor. Specifically,
station_build_handshake_rsn was modified to always build up the RSN
information, not just for SECURITY_8021X and SECURITY_PSK. This is
because OWE needs this RSN information, even though it is still
SECURITY_NONE. Since "regular" open networks don't need this, a check
was added (security == NONE && akm != OWE) which skips the RSN
building.
netdev.c needed to be changed in nearly the same manor as it was for
SAE. When connecting, we check if the AKM is for OWE, and if so create
a new OWE SM and start it. OWE handles all the ECDH, and netdev handles
sending CMD_AUTHENTICATE and CMD_ASSOCIATE when triggered by OWE. The
incoming authenticate/associate events just get forwarded to OWE as they
do with SAE.
This module is similar to SAE in that it communicates over authenticate
and associate frames. Creating a new OWE SM requires registering two TX
functions that handle sending the data out over CMD_AUTHENTICATE/ASSOCIATE,
as well as a complete function.
Once ready, calling owe_start will kick off the OWE process, first by
sending out an authenticate frame. There is nothing special here, since
OWE is done over the associate request/response.
After the authenticate response comes in OWE will send out the associate
frame which includes the ECDH public key, and then receive the AP's
public key via the associate response. From here OWE will use ECDH to
compute the shared secret, and the PMK/PMKID. Both are set into the
handshake object.
Assuming the PMK/PMKID are successfully computed the OWE complete callback
will trigger, meaning the 4-way handshake can begin using the PMK/PMKID
that were set in the handshake object.
The RFC (5869) for this implementation defines two functions,
HKDF-Extract and HKDF-Expand. The existing 'hkdf_256' was implementing
the Extract function, so it was renamed appropriately. The name was
changed for consistency when the Expand function will be added in the
future.
In the current version SECURITY_PSK was handled inside the is_rsn block
while the SECURITY_8021X was off in its own block. This was weird and a
bit misleading. Simplify the code flow through the use of a goto and
decrease the nesting level.
Also optimize out unnecessary use of scan_bss_get_rsn_info
In network_autoconnect, when the network was SECURITY_8021X there was no
check (for SECURITY_PSK) before calling network_load_psk. Since the
provisioning file was for an 8021x network neither PreSharedKey or
Passphrase existed so this would always fail. This fixes the 8021x failure
in testConnectAutoconnect.
During the handshake setup, if security != SECURITY_PSK then 8021x settings
would get set in the handshake object. This didn't appear to break anything
(e.g. Open/WEP) but its better to explicitly check that we are setting up
an 8021x network.
Check for HAVE_EXECINFO_H for all __iwd_backtrace_init usages.
Fixes:
src/main.o: In function `main':
main.c:(.text.startup+0x798): undefined reference to `__iwd_backtrace_init'
collect2: error: ld returned 1 exit status
A sorted list of hidden network BSSs observed in the recent scan
is kept for the informational purposes of the clients. In addition,
it has deprecated the usage of seen_hidden_networks variable.
Refactor the network->psk and network->passphrase loading and saving
logic to not require the PreSharedKey entry in the psk config file and
to generate network->psk lazily on request. Still cache the computed
PSK in memory and in the .psk file to avoid recomputing it which uses
many syscalls. While there update the ask_psk variable to
ask_passphrase because we're specifically asking for the passphrase.
According to the specification, Supported rates IE is supposed
to have a maximum length of eight rate bytes. In the wild an
Access Point is found to add 12 bytes of data instead of placing
excess rate bytes in an Extended Rates IE.
BSS: len 480
BSSID 44:39:C4:XX:XX:XX
Probe Response: true
TSF: 0 (0x0000000000000000)
IEs: len 188
...
Supported rates:
1.0(B) 2.0(B) 5.5(B) 6.0(B) 9.0 11.0(B) 12.0(B) 18.0 Mbit/s
24.0(B) 36.0 48.0 54.0 Mbit/s
82 84 8b 8c 12 96 98 24 b0 48 60 6c .......$.H`l
DSSS parameter set: channel 3
03
...
Any following IEs decode nicely, thus it seems that we can relax
Supported Rates IE length handling to support this thermostat.
After moving AP EAPoL code into eapol.c there were a few functions that
no longer needed to be public API's. These were changed to static's and
the header definition was removed.
Set an upper limit on a fragmented EAP-TLS request size similar to how
we do it in EAP-TTLS. While there make the code more similar to the
EAP-TTLS flag processing to keep them closer in sync. Note that the
spec suggests a 64KB limit but it's not clear if that is for the TLS
record or EAP request although it takes into account the whole TLS
negotiation so it might be good for both.
Some of the TTLS server implementations set the L flag in the fragment
packets other than the first one. To stay interoperable with such devices,
iwd is relaxing the L bit check.
Switch EAP-MD5 to use the common password setting key nomenclature.
The key name has been changed from PREFIX-MD5-Secret to PREFIX-Password.
Note: The old key name is supported.
In addition, this patch adds an ability to request Identity and/or
Password from user.
Adhoc was not waiting for BOTH handshakes to complete before adding the
new peer to the ConnectedPeers property. Actually waiting for the gtk/igtk
(in a previous commit) helps with this, but adhoc also needed to keep track
of which handshakes had completed, and only add the peer once BOTH were done.
This required a small change in netdev, where we memcmp the addresses from
both handshakes and only set the PTK on one.
Currently, netdev triggers the HANDSHAKE_COMPLETE event after completing
the SET_STATION (after setting the pairwise key). Depending on the timing
this may happen before the GTK/IGTK are set which will result in group
traffic not working initially (the GTK/IGTK would still get set, but group
traffic would not work immediately after DBus said you were connected, this
mainly poses a problem with autotests).
In order to fix this, several flags were added in netdev_handshake_state:
ptk_installed, gtk_installed, igtk_installed, and completed. Each of these
flags are set true when their respective keys are set, and in each key
callback we try to trigger the handshake complete event (assuming all the
flags are true). Initially the gtk/igtk flags are set to true, for reasons
explained below.
In the WPA2 case, all the key setter functions are called sequentially from
eapol. With this change, the PTK is now set AFTER the gtk/igtk. This is
because the gtk/igtk are optional and only set if group traffic is allowed.
If the gtk/igtk are not used, we set the PTK and can immediately trigger the
handshake complete event (since gtk_installed/igtk_installed are initialized
as true). When the gtk/igtk are being set, we immediately set their flags to
false and wait for their callbacks in addition to the PTK callback. Doing it
this way handles both group traffic and non group traffic paths.
WPA1 throws a wrench into this since the group keys are obtained in a
separate handshake. For this case a new flag was added to the handshake_state,
'wait_for_gtk'. This allows netdev to set the PTK after the initial 4-way,
but still wait for the gtk/igtk setters to get called before triggering the
handshake complete event. As a precaution, netdev sets a timeout that will
trigger if the gtk/igtk setters are never called. In this case we can still
complete the connection, but print a warning that group traffic will not be
allowed.
==1628== Invalid read of size 1
==1628== at 0x405E71: hardware_rekey_cb (netdev.c:1381)
==1628== by 0x444E5B: process_unicast (genl.c:415)
==1628== by 0x444E5B: received_data (genl.c:534)
==1628== by 0x442032: io_callback (io.c:126)
==1628== by 0x4414CD: l_main_iterate (main.c:387)
==1628== by 0x44158B: l_main_run (main.c:434)
==1628== by 0x403775: main (main.c:489)
==1628== Address 0x5475208 is 312 bytes inside a block of size 320 free'd
==1628== at 0x4C2ED18: free (vg_replace_malloc.c:530)
==1628== by 0x43D94D: l_queue_clear (queue.c:107)
==1628== by 0x43D998: l_queue_destroy (queue.c:82)
==1628== by 0x40B431: netdev_shutdown (netdev.c:4765)
==1628== by 0x403B17: iwd_shutdown (main.c:81)
==1628== by 0x4419D2: signal_callback (signal.c:82)
==1628== by 0x4414CD: l_main_iterate (main.c:387)
==1628== by 0x44158B: l_main_run (main.c:434)
==1628== by 0x403775: main (main.c:489)
==1628== Block was alloc'd at
==1628== at 0x4C2DB6B: malloc (vg_replace_malloc.c:299)
==1628== by 0x43CA4D: l_malloc (util.c:62)
==1628== by 0x40A853: netdev_create_from_genl (netdev.c:4517)
==1628== by 0x444E5B: process_unicast (genl.c:415)
==1628== by 0x444E5B: received_data (genl.c:534)
==1628== by 0x442032: io_callback (io.c:126)
==1628== by 0x4414CD: l_main_iterate (main.c:387)
==1628== by 0x44158B: l_main_run (main.c:434)
==1628== by 0x403775: main (main.c:489)
Adhoc requires 2 GTK's to be set, a single TX GTK and a per-mac RX GTK.
The per-mac RX GTK already gets set via netdev_set_gtk. The single TX GTK
is created the same as AP, where, upon the first station connecting a GTK
is generated and set in the kernel. Then any subsequent stations use
GET_KEY to retrieve the GTK and set it in the handshake.
AdHoc will also need the same functionality to verify and parse the
key sequence from GET_KEY. This block of code was moved from AP's
GET_KEY callback into nl80211_parse_get_key_seq.
Netdev/AP share several NL80211 commands and each has their own
builder API's. These were moved into a common file nl80211_util.[ch].
A helper was added to AP for building NEW_STATION to make the associate
callback look cleaner (rather than manually building NEW_STATION).
Check that netdev->device is not NULL before doing device_remove()
(which would crash) and emitting NETDEV_WATCH_EVENT_DEL. It may be
NULL if the initial RTM_SETLINK has failed to bring device UP.
If there are Ad-hoc BSSes they should be present in the scan results
together with regular APs as far as scan.c is concerned. But in
station mode we can't connect to them -- the Connect method will fail and
autoconnect would fail. Since we have no property to indicate a
network is an IBSS just filter these results out for now. There are
perhaps better solutions but the benefit is very low.
This is a replacement for station's static select_akm_suite. This was
done because wiphy can make a much more intellegent decision about the
akm suite by checking the wiphy supported features e.g. SAE support.
This allows a connection to hybrid WPA2/WPA3 AP's if SAE is not
supported in the kernel.
Set a default GTK cipher type same as our current PTK type, generate a
random GTK when the first STA connects and set it up in the kernel, then
pass the values that EAPoL is going to need to the handshake_state.
In netdev_set_powered also check that no NL80211_CMD_SET_INTERFACE is in
progress because once it returned we would overwrite
netdev->set_powered_cmd_id (could also add a check there but it seems
more logical to just disallow Powered property changes while Mode is
being changed, since we also disallow Mode changes while Powered is
being changed.)
Since device object no longer creates / destroys station objects, use
station_find inside ap directed roam events to direct these to the
station interface.
Add places to store the GTK data, index and RSC in struct
handshake_state and add a setter function for these fields. We may want
to also convert install_gtk to use these fields similar to install_ptk.
As a consequence of the previous commit, netdev watches are always
called when the device object is valid. As a result, we can drop the
netdev_get_device calls and checks from individual AP/AdHoc/Station/WSC
netdev watches
Instead of creating the Station interface in device.c create it directly
on the netdev watch event the same way that the AP and AdHoc interfaces
are created and freed. This fixes some minor incosistencies, for
example station_free was previously called twice, once from device.c and
once from the netdev watch.
device.c would previously keep the pointer returned by station_create()
but that pointer was not actually useful so remove it. Autotests still
seem to pass.
Call netdev_disconnect() to make netdev forget any of station.c's
callbacks for connections or transitions in progress or established.
Otherwise station.c will crash as soon as we're connected and try to
change interface mode:
==17601== Invalid read of size 8
==17601== at 0x11DFA0: station_disconnect_event (station.c:775)
==17601== by 0x11DFA0: station_netdev_event (station.c:1570)
==17601== by 0x115D18: netdev_disconnect_event (netdev.c:868)
==17601== by 0x115D18: netdev_mlme_notify (netdev.c:3403)
==17601== by 0x14E287: l_queue_foreach (queue.c:441)
==17601== by 0x1558B4: process_multicast (genl.c:469)
==17601== by 0x1558B4: received_data (genl.c:532)
==17601== by 0x152888: io_callback (io.c:123)
==17601== by 0x151BCD: l_main_iterate (main.c:376)
==17601== by 0x151C9B: l_main_run (main.c:423)
==17601== by 0x10FE20: main (main.c:489)
Since the interfaces are not supposed to exist when the device is DOWN
(we destroy the interfaces on NETDEV_WATCH_EVENT_DOWN too), don't
create the interfaces if the device hasn't been brought up yet.
When we detect a new device we either bring it down and then up or only
up. The IFF_UP flag in netdev->ifi_flags is updated before that, then
we send the two rtnl commands and then fire the NETDEV_WATCH_EVENT_NEW
event if either the bring up succeeded or -ERFKILL was returned, so the
device may either be UP or DOWN at that point.
It seems that a RTNL NEWLINK notification is usually received before
the RTNL command callback but I don't think this is guaranteed so update
the IFF_UP flag in the callbacks so that the NETDEV_WATCH_EVENT_NEW
handlers can reliably use netdev_get_is_up()
The NL80211_ATTR_KEY_DEFAULT_TYPES attribute is only parsed by the
kernel if either NL80211_ATTR_KEY_DEFAULT or
NL80211_ATTR_KEY_DEFAULT_MGMT are also present, however these are only
used with NL80211_CMD_SET_KEY and ignored for NEW_KEY. As far as I
understand the default key concept only makes sense for a Tx key because
on Rx all keys can be tried, so we don't need this for client mode. The
kernel decides whether the NEW_KEY is for unicast or multicast based on
whether NL80211_ATTR_KEY_MAC was supplied.
device password was read from settings using l_settings_get_string which
returns a newly-allocated string due to un-escape semantics. However,
when assigning wsc->device_password, we strdup-ed the password again
unnecessarily.
==1069== 14 bytes in 2 blocks are definitely lost in loss record 1 of 1
==1069== at 0x4C2AF0F: malloc (vg_replace_malloc.c:299)
==1069== by 0x16696A: l_malloc (util.c:62)
==1069== by 0x16B14B: unescape_value (settings.c:108)
==1069== by 0x16D12C: l_settings_get_string (settings.c:971)
==1069== by 0x149680: eap_wsc_load_settings (eap-wsc.c:1270)
==1069== by 0x146113: eap_load_settings (eap.c:556)
==1069== by 0x12E079: eapol_start (eapol.c:2022)
==1069== by 0x1143A5: netdev_connect_event (netdev.c:1728)
==1069== by 0x118751: netdev_mlme_notify (netdev.c:3406)
==1069== by 0x1734F1: notify_handler (genl.c:454)
==1069== by 0x168987: l_queue_foreach (queue.c:441)
==1069== by 0x173561: process_multicast (genl.c:469)
wsc_pin_is_valid allows two types of PINs through:
1. 4 digit numeric PIN
2. 8 digit numeric PIN
The current code always calls wsc_pin_is_checksum_valid to determine
whether a DEFAULT or USER_SPECIFIED PIN is used. However, this function
is not safe to call on 4 digit PINs and causes a buffer overflow.
Add simple checks to treat 4 digit PINs as DEFAULT PINs and do not call
wsc_pin_is_checksum_valid on these.
Reported-By: Matthias Gerstner <matthias.gerstner@suse.de>
EAP-WSC handles 4 digit, 8 digit and out-of-band Device passwords. The
latter in particular can be anything, so drop the mandatory minimum
password length check here.
This also has the effect of enabling 4-digit PINs to actually work as
they are intended.
The struct allows to support multiple types of the tunneled methods.
Previously, EAP-TTLS was supporting only the eap based ones.
This patch is also starts to move some of the phase 2 EAP
functionality into the new structure.
Boiled down, FT over SAE is no different than FT over PSK, apart from
the different AKM suite. The bulk of this change fixes the current
netdev/station logic related to SAE by rebuilding the RSNE and adding
the MDE if present in the handshake to match what the PSK logic does.
A common function was introduced into station which will rebuild the
handshake rsne's for a target network. This is used for both new
network connections as well as fast transitions.
To prepare for FT over SAE, several case/if statements needed to include
IE_RSN_AKM_SUITE_FT_OVER_SAE. Also a new macro was introduced to remove
duplicate if statement code checking for both FT_OVER_SAE and SAE AKM's.
All the watchlist notify macros were broken in that they did not check
that the watchlist item was still valid before calling it. This only
came into play when a watchlist was being notified and one of the notify
functions removed an item from the same watchlist. It appears this was
already thought of since watchlist_remove checks 'in_notify' and will
mark the item's id as stale (0), but that id never got checked in the
notify macros.
This fixes testAdHoc valgrind warning:
==3347== Invalid read of size 4
==3347== at 0x416612: eapol_rx_auth_packet (eapol.c:1871)
==3347== by 0x416DD4: __eapol_rx_packet (eapol.c:2334)
==3347== by 0x40725B: netdev_pae_read (netdev.c:3515)
==3347== by 0x440958: io_callback (io.c:123)
==3347== by 0x43FDED: l_main_iterate (main.c:376)
==3347== by 0x43FEAB: l_main_run (main.c:423)
==3347== by 0x40377A: main (main.c:489)
...
In the case of the open networks with hidden SSIDs
the settings object is already created.
Valgrind:
==4084== at 0x4C2EB6B: malloc (vg_replace_malloc.c:299)
==4084== by 0x43B44D: l_malloc (util.c:62)
==4084== by 0x43E3FA: l_settings_new (settings.c:83)
==4084== by 0x41D101: network_connect_new_hidden_network (network.c:1053)
==4084== by 0x4105B7: station_hidden_network_scan_results (station.c:1733)
==4084== by 0x419817: scan_finished (scan.c:1165)
==4084== by 0x419CAA: get_scan_done (scan.c:1191)
==4084== by 0x443562: destroy_request (genl.c:139)
==4084== by 0x4437F7: process_unicast (genl.c:424)
==4084== by 0x4437F7: received_data (genl.c:534)
==4084== by 0x440958: io_callback (io.c:123)
==4084== by 0x43FDED: l_main_iterate (main.c:376)
==4084== by 0x43FEAB: l_main_run (main.c:423)
Some of the PEAP server implementations set the L flag along with
redundant TLS Message Length field for the un-fragmented packets.
This patch allows to identify and handle such occasions.
EAP Extensions type 33 is used in PEAPv0 as a termination
mechanism for the tunneled EAP methods. In PEAPv1
the regular EAP-Success/Failure packets must be used to terminate
the method. Some of the server implementations of PEAPv1
rely on EAP Extensions method to terminate the conversation
instead of the required Success/Failure packets. This patch
makes iwd interoperable with such devices.
The "H" function used by SAE and EAP-PWD was effectively the same
function, EAP-PWD just used a zero key for its calls. This removes
the duplicate implementations and merges them into crypto.c as
"hkdf_256".
Since EAP-PWD always uses a zero'ed key, passing in a NULL key to
hkdf_256 will actually use a 32 byte zero'ed array as the key. This
avoids the need for EAP-PWD to store or create a zero'ed key for
every call.
Both the original "H" functions never called va_end, so that was
added to hkdf_256.
The ifindex as reported by netdev is unsigned, so make sure that it is
printed as such. It is astronomically unlikely that this causes any
actual issues, but lets be paranoid.
Move the roam initiation (signal loss, ap directed roaming) and scanning
details into station from device. Certain device functions have been
exposed temporarily to make this possible.
process_bss performs two main operations. It adds a seen BSS to a
network object (existing or new) and if the device is in the autoconnect
state, it adds an autoconnect entry as needed. Split this operation
into two separate & independent steps.
To avoid confusion in case of an authenticator side handshake_state
structure and eapol_sm structure, rename own_ie to supplicant_ie and
ap_ie to authenticator_ie. Also rename
handshake_state_set_{own,ap}_{rsn,wpa} and fix when we call
handshake_state_setup_own_ciphers. As a result
handshake_state_set_authenticator, if needed, should be called before
handshake_state_set_{own,ap}_{rsn,wpa}.
After EAPOL logic was moved to eapol.c a check was added to
ap_associate_sta_cb to bitwise compare the AP's RSNE to the RSNE
received in the (Re)Association frame. There is as far as I know no
reason for them to be the same (although they are in our autotest) and
if there was a reason we'd rather validate the (Re)Association RSNE
immediately when received. We also must set different RSNEs as the
"own" (supplicant) and "ap" RSNEs in the handshake_state for validation
of step 2/4 in eapol.c (fixes wpa_supplicant's and MS Windows
connections being rejected)
Make sure we interrupt eapol traffic (4-way handshake) if we receive a
Disassociation from station. Actually do this in ap_del_station because
it's called from both ap_disassoc_cb and ap_success_assoc_resp_cb and
seems to make sense in both cases.
On one hand when we're called with HANDSHAKE_EVENT_FAILED or
HANDSHAKE_EVENT_SETTING_KEYS_FAILED the eapol_sm will be freed in
eapol.c, fix a double-free by setting it to NULL before ap_free_sta
is called.
On the other hand make sure we call eapol_sm_free before setting
sta->sm to NULL in ap_drop_rsna to avoid potential leak and avoid
the eapol_sm continuing to use the handshake_state we freed.
timespec_compare wanted to receive network_info structures as arguments
to compare connected_time timestamps but in one instance we were passing
actual timespec structures. Add a new function to compare plain timespec
values and switch the names for readability.
==7330== 112 bytes in 1 blocks are still reachable in loss record 1 of 1
==7330== at 0x4C2CF8F: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==7330== by 0x14CF7D: l_malloc (util.c:62)
==7330== by 0x152A25: l_io_new (io.c:172)
==7330== by 0x16B217: l_fswatch_init (fswatch.c:171)
==7330== by 0x16B217: l_fswatch_new (fswatch.c:198)
==7330== by 0x13B9D9: known_networks_init (knownnetworks.c:401)
==7330== by 0x110020: main (main.c:439)
There was somewhat overlapping functionality in the device_watch
infrastructure as well as the netdev_event_watch. This commit combines
the two into a single watch based on the netdev object and cleans up the
various interface additions / removals.
With this commit the interfaces are created when the netdev/device is
switched to Powered=True state AND when the netdev iftype is also in the
correct state for that interface. If the device is brought down, then
all interfaces except the .Device interface are removed.
This will make it easy to implement Device.Mode property properly since
most nl80211 devices need to be brought into Powered=False state prior
to switching the iftype.
The way that netdev_set_linkmode_and_operstate was used resulted in
potential crashes when the netdev was destroyed. This is because netdev
was given as data to l_netlink_send and could be destroyed between the
time of the call and the callback. Since the result of calls to
netdev_set_linkmode_and_operstate is inconsequential, it isn't really
worthwhile tracking these calls in order to cancel them.
This patch simplies the handling of these rtnl calls, makes sure that
netdev isn't passed as user data and rewrites the
netdev_set_linkmode_and_operstate signature to be more consistent with
rtnl_set_powered.
Since all netdevs share the rtnl l_netlink object, it was possible for
netdevs to be destroyed with outstanding commands still executing on the
rtnl object. This can lead to crashes and other nasty situations.
This patch makes sure that Powered requests are always tracked via
set_powered_cmd_id and the request is canceled when netdev is destroyed.
This also implies that netdev_set_powered can now return an -EBUSY error
in case a request is already outstanding.
SAE is meant to work in a peer-to-peer fashion where neither side acts
as a dedicated authenticator or supplicant. This was not the case with
the current code. The handshake state authenticator address was hard
coded as the destination address for all packets, which will not work
when mesh comes into play. This also made unit testing the full SAE
procedure with two sae_sm's impossible.
This patch adds a peer address element to sae_sm which is filled with
either aa/spa based on the value of handshake->authenticator
This removes the authenticator bit in eapol_sm as well as unifies
eapol_register_authenticator and eapol_register. Taking advantage
of the handshake state authenticator bit we no longer have a need
for 2 separate register functions.
ap, and adhoc were also updated to set the authenticator bit in
the handshake and only use eapol_register to register their sm's.
netdev was updated to use the authenticator bit when choosing the
correct key address for adhoc.
Both SAE and adhoc can benefit from knowing whether the handshake state
is an authenticator or a supplicant. It will allow both to easily
obtain the remote address rather than sorting out if aa/spa match the
devices own address.
The send confirm counter is incremented before calling sae_send_confirm
in all cases, but the function itself was also incrementing sc after
sending the packet. This isn't critical to the successful execution of
SAE as the AP just uses the sc value in the packet but it did violate
the 802.11 spec.
In order to plug SAE into the existing connect mechanism the actual
CMD_CONNECT message is never sent, rather sae_register takes care
of sending out CMD_AUTHENTICATE. This required some shuffling of
code in order to handle both eapol and sae. In the case of non-SAE
authentication everything behaves as it did before. When using SAE
an sae_sm is created when a connection is attempted but the eapol_sm
is not. After SAE succeeds it will start association and then create
the eapol_sm and start the 4-way handshake.
This change also adds the handshake SAE events to device and
initializes SAE in main.
SAE (Simultaneous Authentication of Equals) takes place during
authentication, and followed by EAPoL/4-way handshake. This
module handles the entire SAE commit/confirm exchange. This was
done similar to eapol.
SAE begins when sae_register is called. At this point a commit
message will be created and sent out which kicks off the SAE
authentication procedure.
The commit/confirm exchange is very similar to EAP-PWD, so all
the ecc utility functions could be re-used as-is. A few new ecc
utility functions were added to conform to the 80211 'blinding'
technique for computing the password element.
For an SAE network, the raw passphrase is required. For this reason,
known network psk files should now always contain a 'Passphrase' entry.
If a psk file is found without a Passphrase entry the agent will be asked
for the Passphrase before connecting. This will update the legacy psk
file with the Passphrase entry.
Due to the quirk in how storage_network_sync implements file writing,
iwd was generating unnecessary KnownNetwork removal events (and
preventing certain test cases from passing successfully)
storage_network_sync tries to perform atomic writes by writing to a
temporary storage location first, unlinking the existing file and
renaming the tmp file as the original.
This generates a set of inotify events which confuses the current
implementation.
The previous change did not consider the case of the PSK being written
for the very first time. In this case storage_network_open would return
NULL and an empty file would be written.
Change this so that if storage_network_open fails, then the current
network settings are written to disk and not a temporary.
Reload the network settings from disk before calling
storage_network_sync in network_sync_psk to avoid potentially
overwriting changes made to the storage by user since the connection
attempt started. This won't account for all situations but it
covers some of them and doesn't cost us much.
Our logic would set CONTROL_PORT_OVER_NL80211 even in cases where
CONTROL_PORT wasn't used (e.g. for open networks). While the kernel
ignored this attribute in this case, it is nicer to set this only if
CONTROL_PORT is intended to be used.
SAE will require some of the same CMD_ASSOCIATE building code that
FT currently uses. This breaks out the common code from FT into
netdev_build_cmd_associate_common.
This also required passing in the akm suite in case the key description
version was zero. In the zero case the akm must be checked. For now this
only supports the SAE akm.
Update the known networks list and network properties on file creations,
removals and modifications. We watch for these filesystem events using
ell's fswatch and react accordingly.
This makes testEAP-PEAP-GTC pass for me by re-adding the check for the
GTC-Secret setting which was replaced with the check for the secrets
list in 3d2285ec7e.
eap_append_secret now takes a new cache_policy parameter which can be
used by the EAP method to signal that the value received from the agent
is to never be cached, i.e. each value can only be used once. The
parameter value should be EAP_CACHE_NEVER for this and we use this in
value EAP-GTC where the secret tokens are one time use. The
EAP_CACHE_TEMPORARY value is used in other methods, it preserves the
default behaviour where a secret can be cached for as long as the
network stays in range (this is the current implementation more than a
design choice I believe, I didn't go for a more specific enum name as
this may still change I suppose).
SAE generates the PMKID during the authentication process, rather than
generating it on-the-fly using the PMK. For this reason SAE needs to be
able to set the PMKID once its generated. A new flag was also added
(has_pmkid) which signifies if the PMKID was set or if it should be
generated.
SAE needs access to the raw passphrase, not the PSK which network
saves. This changes saves the passphrase in network and handshake
objects, as well as adds getters to both objects so SAE can retrieve
the passphrase.
This fixes improper cleanup when ofono leaves the bus after a simauth
instance has been cleaned up. The problem was that the plugin
exit was being called after the simauth module, causing there to
be stale simauth instances that were no longer valid. Now plugins
cleanup before simauth.
This fix fixes the print seen when iwd exits:
"Auth provider queue was not empty on exit!"
Make the network_storage_* functions uniformly accept an enum value
instead of a string so that he conversion to string doesn't need to
happen in all callers.
Now, EAP-GTC behaves similar to MSCHAPv2 where check_settings allows
for missing EAP-Identity and GTC-Secret fields. Either or both can be
missing and the agent will request the missing fields.
Add ObjectManager objects with properties for each Known Network so that
signals are emitted for creation or removal of a Known Network and a
Property Changed is emitted on LastConnectedTime change. Remove the
ListKnownNetworks method from the old KnownNetworks interface.
Note this breaks clients that used the known networks interface.
Drop the corresponding network_info field, function and D-Bus property.
The last seen times didn't seem useful but if a client needs them it can
probably implement the same logic with the information already available
through DBus.
If the sm object (or the handshake object) is NULL, don't call the
corresponding function.
0 0x7fb6cd37da80 in /lib64/libc.so.6
1 0x414764 in eapol_sm_destroy() at eapol.c:673
2 0x42e402 in ap_sta_free() at ap.c:97
3 0x439dbe in l_queue_clear() at /home/parallels/wrk/iwd/ell/queue.c:109
4 0x439e09 in l_queue_destroy() at /home/parallels/wrk/iwd/ell/queue.c:83
5 0x42e4bf in ap_reset() at ap.c:132
6 0x42e519 in ap_free() at ap.c:147
7 0x447456 in interface_instance_free() at /home/parallels/wrk/iwd/ell/dbus-service.c:513
8 0x449be0 in _dbus_object_tree_remove_interface() at /home/parallels/wrk/iwd/ell/dbus-service.c:1595
9 0x449ced in _dbus_object_tree_object_destroy() at /home/parallels/wrk/iwd/ell/dbus-service.c:787
10 0x40fb8c in device_free() at device.c:2717
11 0x405cdb in netdev_free() at netdev.c:605
12 0x439dbe in l_queue_clear() at /home/parallels/wrk/iwd/ell/queue.c:109
13 0x439e09 in l_queue_destroy() at /home/parallels/wrk/iwd/ell/queue.c:83
14 0x40aac2 in netdev_shutdown() at netdev.c:4483
15 0x403b75 in iwd_shutdown() at main.c:80
16 0x43d9f3 in signal_callback() at /home/parallels/wrk/iwd/ell/signal.c:83
17 0x43d4ee in l_main_iterate() at /home/parallels/wrk/iwd/ell/main.c:376
18 0x43d5ac in l_main_run() at /home/parallels/wrk/iwd/ell/main.c:419
19 0x40379b in main() at main.c:454
20 0x7fb6cd36788a in /lib64/libc.so.6
Until now network.c managed the list of network_info structs including
for known networks and networks that are seen in at least one device's
scan results, with the is_known flag to distinguish known networks.
Each time the list was processed though the code was either interested
in one subset of networks or the other. Split the list into a Known
Networks list and the list of other networks seen in scans. Move all
code related to Known Networks to knownnetworks.c, this simplifies
network.h. It also gets rid of network_info_get_known which actually
returned the list of all network_infos (not just for known networks),
which logically should have been private to network.c. Update device.c
and scan.c to use functions specific to Known Networks instead of
filtering the lists by the is_known flag.
This will also allow knownnetworks.c to export DBus objects and/or
properties for the Known Networks information because it now knows when
Known Networks are added, removed or modified by IWD.
The return value from network_connected is not checked and even if one
of the storage operations fails the function should probably continue
so only print a message on error.
If the device mode it toggled from 'ap' back to 'station' without actually
starting the access point ap_free attempts to zero out the psk, which
causes a crash because it had never been allocated (Start() never was
called). Since ap->psk is actually never used this was removed. Also added
a memset to zero out the pmk on cleanup.
This is the crash observed:
++++++++ backtrace ++++++++
0 0x7f6ffe978a80 in /lib64/libc.so.6
1 0x7f6ffe9d6766 in /lib64/libc.so.6
2 0x42dd51 in memset() at /usr/include/bits/string3.h:90
3 0x42ddd9 in ap_free() at src/ap.c:144
4 0x445ec6 in interface_instance_free() at ell/dbus-service.c:513
5 0x448650 in _dbus_object_tree_remove_interface() at ell/dbus-service.c:1595
6 0x40d980 in device_set_mode_sta() at src/device.c:2113
7 0x447d4c in properties_set() at ell/dbus-service.c:1861
8 0x448a33 in _dbus_object_tree_dispatch() at ell/dbus-service.c:1691
9 0x442587 in message_read_handler() at ell/dbus.c:285
10 0x43cac9 in io_callback() at ell/io.c:123
11 0x43bf5e in l_main_iterate() at ell/main.c:376
12 0x43c01c in l_main_run() at ell/main.c:419
13 0x40379d in main() at src/main.c:460
14 0x7f6ffe96288a in /lib64/libc.so.6
+++++++++++++++++++++++++++
- wsc module does not need nl80211 any longer, so remove it.
- Move wsc_init & wsc_exit declarations to iwd.h and remove wsc.h
- re-arrange how wsc_init & wsc_exit is called inside main.c.
The plugin_exit was in the wrong place, it should be triggered in case
genl creation fails. Also adhoc_exit was in the wrong sequence compared
to _init()
Rather than have device.c manage the creation/removal of
AP/AdHoc interfaces this new event was introduced. Now
anyone can listen for device events and if the mode changes
handle accordingly. This fixes potential memory leaks
in WSC when switching modes as well.
These will issue a JOIN/LEAVE_IBSS to the kernel. There is
a TODO regarding network configuration. For now, only the
SSID is configurable. This configuration is also required
for AP, but needs to be thought out. Since the current
AP Dbus API has nothing related to configuration items
such as freq/channel or RSN elements they are hard coded,
and will be for Ad-Hoc as well (for now).
Now that the device mode can be changed, netdev must check that
the iftype is correct before starting a connection or disconnecting.
netdev_connect, netdev_connect_wsc, and netdev_disconnect now check
that the iftype is station before continuing.
With the introduction of Ad-Hoc, its not as simple as choosing
aa/spa addresses when setting the keys. Since Ad-Hoc acts as
both the authenticator and supplicant we must check how the netdev
address relates to the particular handshake object as well as
choose the correct key depending on the value of the AA/SPA address.
802.11 states that the higher of the two addresses is to be used
to set the key for the Ad-Hoc connection.
A simple helper was added to choose the correct addressed based on
netdev type and handshake state. netdev_set_tk also checks that
aa > spa in the handshake object when in Ad-Hoc mode. If this is
true then the keys from that handshake are used, otherwise return
and the other handshake key will be used (aa will be > spa).
The station/ap mode behaves exactly the same as before.
For Ad-Hoc networks, the kernel takes care of auth/assoc
and issues a NEW_STATION event when that is complete. This
provides a way to notify when NEW_STATION events occur as
well as forward the MAC of the station to Ad-Hoc.
The two new API's added:
- netdev_station_watch_add()
- netdev_station_watch_remove()
When the EAPOL-Key data field is encrypted using AES Wrap, check
that the data field is large enough before calculating the expected
plaintext length.
Previously, if the encrypted data field was smaller than 8 bytes, an
integer underflow would occur when calculating the expected plaintext
data length. This would cause iwd to try to allocate a huge amount of
memory, which causes it to abort and terminate. If the data field was
equal to 8 bytes, iwd would try to allocate 0 bytes of memory, making
l_new return NULL, which subsequently causes iwd to crash on a NULL
pointer deference.
Reported-by: Mathy Vanhoef <Mathy.Vanhoef@cs.kuleuven.be>
triggered flag was being reset to false in all cases. However, due to
how scan_finished logic works, it should have remained true if no more
commands were left to be sent (e.g. the scan was finished).
Having hidden SSIDs or SSIDs with non-UTF8 characters around make iwd
flood the logs with messages. Make iwd less verbose and show these
messages with enabled debug output only.
In addition, the periodic scan can now alternate between the
active or passive modes. The active mode is enabled by existence of
the known hidden networks and observation of them in the
previous scan result.
To support an auto-connect for the hidden networks and having
a limited number of SSIDs that can be appended into a probe
request, introduced a concept of a command batch. Now, scan request
may consist of a series of commands. The commands in the batch
are triggered sequentially. Once we are notified about the
results from a previous command, a consequent command in the
batch is triggered. The collective results are reported once
the batch is complete. On a command failure, the batch
processing is canceled and scan request is removed
Rework the logic slightly to simplify the need for error labels. Also
the connect_pending variable might not have been properly reset to NULL
in case of error, so make sure we reset it prior to calling into
network_connect_new_hidden_network
1) Change signature of process_bss to return a confirmation
that bss has been added to a network otherwise we can
discard it.
2) Implements logic for the discovery and connection to
a hidden network.
This removes the need for duplicate code in AP/netdev for issuing
a DEL_STATION command. Now AP can issue a DEL_STATION with
netdev_del_station, and specify to either disassociate or deauth
depending on state.
If netdev fails to set the keys, there was no way for device/ap to
know. A new handshake event was added for this. The key setting
failure function was also fixed to support both AP/station iftypes.
It will now automatically send either a disconnect or del_station
depending on the interface type.
In similar manner, netdev_handshake_failed was also modified to
support both AP/station iftypes. Now, any handshake event listeners
should call netdev_handshake_failed upon a handshake failure
event, including AP.
If device is already disconnected or in autoconnect mode, don't return
an error if .Disconnect is called. Instead simply silently return
success after disabling autoconnect.
==1058== 231 (32 direct, 199 indirect) bytes in 1 blocks are definitely lost in loss record 10 of 10
==1058== at 0x4C2DB8F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==1058== by 0x452472: l_malloc (util.c:62)
==1058== by 0x456324: l_settings_new (settings.c:83)
==1058== by 0x427D45: storage_network_open (storage.c:262)
==1058== by 0x42806C: network_settings_load (network.c:75)
==1058== by 0x428C2F: network_autoconnect (network.c:490)
==1058== by 0x4104E9: device_autoconnect_next (device.c:194)
==1058== by 0x410E38: device_set_scan_results (device.c:393)
==1058== by 0x410EFA: new_scan_results (device.c:414)
==1058== by 0x424A6D: scan_finished (scan.c:1012)
==1058== by 0x424B88: get_scan_done (scan.c:1038)
==1058== by 0x45DC67: destroy_request (genl.c:134)
This is a fixup for the AP code merge. wsc.c never registered
for handshake events, so in case of failure it was never calling
netdev_handshake_failed, which caused a double free.
Many APs don't send properly zerod key_iv elements in EAPoL-Key frames.
In the past iwd has complained, but this broken behavior is so
prevalent, that it is likely a lost cause.
This patch takes out these warnings
Right now iwd uses Control Port over NL80211 feature if the kernel /
driver supports it. On some kernels this feature is still buggy, so add
an iwd.conf entry to allow the user to override id.
For now the default is to disable this feature until it is more stable.
Now, a user can setup an AP as follows:
- Set device "Mode" to ap (ap interface will appear on bus)
- call "Start()" on AP interface
Issuing "Stop()" on the AP interface will stop and cleanup
the internal AP structures, but the AP interface will remain
up. To shutdown completely the device Mode must be switched
back to station. If the AP interface is running, the Mode can
directly be switched to station without calling Stop; this
has the same effect and will take down the AP interface.
Some of the PEAP server implementation brake the protocol
and don’t set the M flag for the first packet during the
fragmented transmission. To stay compatible with such
devices, we relax this requirement in iwd.
This patch allows alternating between the passive and active
scans taking into consideration an existence of the known
hidden networks and previous observation of them in the scan
results, as well as an ability to randomize the MAC address.
The state of scan is split between the two variables sc->state
and sc->start_cmd_id. Not checking start_cmd_id used to cause
sending a scan request while periodic scan was just triggered
resulting in EBUSY.
Instead of manually sending a deauth/disassociate to a station
during an error or removal, the kernel can do it automatically
with DEL_STATION by including the MGMT_SUBTYPE attribute. This
removes the need for ap_error_deauth_sta and introduces
ap_deauthenticate_sta. Now AP can be explicit when it chooses
to deauth or disassociate.
All handshake packet handling has been removed from ap and
moved to eapol. After association, the AP registers a new
authenticator state machine which handles the AP side of
the handshake. AP will receive a handshake event once the
4-way handshake is complete.
Includes:
- support for handling ptk 2/4 and 4/4. Also sending 1/4 and 3/4.
- new API to register an authenticator SM. This automatically
sends 1/4 to kick off authentication with an sta.
These checks allow both a station and authenticator to use
the same netdev key install functions. For NEW_KEY and
SET_STATION, the iftype is checked and either handshake->aa
or ->spa is used as the station address for the KEY/STATION
commands. Also, in the failure cases, a disconnect command
is issued only if the iftype is station as this doesn't
apply to AP.
Handshake related netdev events were removed in favor of
handshake events. Now events will be emitted on the handshake
object related to the 4-way handshake and key settings. Events
are:
HANDSHAKE_EVENT_STARTED
HANDSHAKE_EVENT_SETTING_KEYS
HANDSHAKE_EVENT_COMPLETE
HANDSHAKE_EVENT_FAILED
Right now, since netdev only operates in station mode, nothing
listens for COMPLETE/FAILED, as device/wsc gets notified by the
connect_cb when the connection was successful. The COMPLETE/
FAILED were added in preperation for AP moving into eapol/netdev.
==1057== 32 bytes in 1 blocks are definitely lost in loss record 1 of 1
==1057== at 0x4C2AF0F: malloc (vg_replace_malloc.c:299)
==1057== by 0x15E9A2: l_malloc (util.c:62)
==1057== by 0x15EA9D: l_memdup (util.c:121)
==1057== by 0x133D9A: network_set_psk (network.c:350)
==1057== by 0x13BD29: wsc_try_credentials (wsc.c:136)
==1057== by 0x13C121: wsc_connect_cb (wsc.c:220)
==1057== by 0x110FAF: netdev_connect_failed (netdev.c:525)
==1057== by 0x16AAF4: process_unicast (genl.c:390)
==1057== by 0x16AF03: received_data (genl.c:509)
==1057== by 0x166CB6: io_callback (io.c:123)
==1057== by 0x16580D: l_main_iterate (main.c:376)
==1057== by 0x16594B: l_main_run (main.c:423)
load_settings ensures that ttls->eap is correctly initialized. So this
code should be treated as an error condition.
We also do not support EAP chaining, so remove that logic as well
dbus_init() currently does not check for the g_dbus object being
properly initialized and this leads to crashes when dbus is not yet
running.
Ensure g_dbus is properly initialized and return false otherwise.
In this case the caller can understand that something went wrong and
stop the initialization procedure.
Program received signal SIGSEGV, Segmentation fault.
0x00005555555bc089 in l_dbus_add_service_watch (dbus=0x0,
name=0x5555555e5b0a "org.ofono",
connect_func=0x5555555aa81e <ofono_found>,
disconnect_func=0x5555555aa8e6 <ofono_disappeared>,
user_data=0x0, destroy=0x0) at ell/dbus.c:1621
1621 if (!dbus->name_cache)
(gdb) bt
name=0x5555555e5b0a "org.ofono",
connect_func=0x5555555aa81e <ofono_found>,
disconnect_func=0x5555555aa8e6 <ofono_disappeared>,
user_data=0x0, destroy=0x0) at ell/dbus.c:1621
user_data=0x0) at ell/plugin.c:115
function=0x5555555b40fd <plugin_start>,
user_data=0x0) at ell/queue.c:441
version=0x0) at ell/plugin.c:201
src/plugin.c:82
src/main.c:417
When the response structure is generated, not all of the memory was
initialized to 0.
==1045== Syscall param socketcall.sendto(msg) points to uninitialised byte(s)
==1045== at 0x5134D52: send (in /lib64/libc-2.25.so)
==1045== by 0x168AB5: l_checksum_update (checksum.c:338)
==1045== by 0x186777: tls_write_mac (tls-record.c:58)
==1045== by 0x1869D1: tls_tx_record_plaintext (tls-record.c:120)
==1045== by 0x186DEA: tls_tx_record (tls-record.c:201)
==1045== by 0x185A3B: l_tls_write (tls.c:2064)
==1045== by 0x14584F: eap_ttls_eap_tx_packet (eap-ttls.c:321)
==1045== by 0x14236C: eap_send_response (eap.c:165)
==1045== by 0x147904: eap_mschapv2_send_response (eap-mschapv2.c:468)
==1045== by 0x147A10: eap_mschapv2_handle_challenge (eap-mschapv2.c:492)
==1045== by 0x147E9A: eap_mschapv2_handle_request (eap-mschapv2.c:615)
==1045== by 0x142693: __eap_handle_request (eap.c:240)
==1045== Address 0x1ffeffe7f9 is on thread 1's stack
==1045== in frame #4, created by tls_tx_record (tls-record.c:177)
==1045== Uninitialised value was created by a stack allocation
==1045== at 0x1477AE: eap_mschapv2_send_response (eap-mschapv2.c:443)
==1045==
==1045== Syscall param sendmsg(msg.msg_iov[0]) points to uninitialised byte(s)
==1045== at 0x5134E3B: sendmsg (in /lib64/libc-2.25.so)
==1045== by 0x17F691: operate_cipher (cipher.c:356)
==1045== by 0x17F9D8: l_cipher_encrypt (cipher.c:446)
==1045== by 0x186BAA: tls_tx_record_plaintext (tls-record.c:152)
==1045== by 0x186DEA: tls_tx_record (tls-record.c:201)
==1045== by 0x185A3B: l_tls_write (tls.c:2064)
==1045== by 0x14584F: eap_ttls_eap_tx_packet (eap-ttls.c:321)
==1045== by 0x14236C: eap_send_response (eap.c:165)
==1045== by 0x147904: eap_mschapv2_send_response (eap-mschapv2.c:468)
==1045== by 0x147A10: eap_mschapv2_handle_challenge (eap-mschapv2.c:492)
==1045== by 0x147E9A: eap_mschapv2_handle_request (eap-mschapv2.c:615)
==1045== by 0x142693: __eap_handle_request (eap.c:240)
==1045== Address 0x1ffeffe7f9 is on thread 1's stack
==1045== in frame #4, created by tls_tx_record (tls-record.c:177)
==1045== Uninitialised value was created by a stack allocation
==1045== at 0x1477AE: eap_mschapv2_send_response (eap-mschapv2.c:443)
==1045==
Since PEAP & TTLS expect to use eap_check_settings recursively, make
them use a private version of that API that does not perform cleanup and
can contain side-effects.
eap_check_settings itself will guarantee that no side effects happen on
error. It is meant to be used by code outside of the eap subsystem.
Missing secrets are freed by eap_send_agent_req() even in case of
failure, so it was erroneous to try to free them on error.
==1048== Invalid read of size 8
==1048== at 0x1603EC: l_queue_clear (queue.c:101)
==1048== by 0x1603B8: l_queue_destroy (queue.c:82)
==1048== by 0x135328: network_connect_8021x (network.c:943)
==1048== by 0x1354C4: network_connect (network.c:987)
==1048== by 0x178DD2: _dbus_object_tree_dispatch (dbus-service.c:1690)
==1048== by 0x16D32A: message_read_handler (dbus.c:285)
==1048== by 0x166EC3: io_callback (io.c:123)
==1048== by 0x165A1A: l_main_iterate (main.c:376)
==1048== by 0x165B58: l_main_run (main.c:423)
==1048== by 0x1102DA: main (main.c:458)
==1048== Address 0x5461850 is 0 bytes inside a block of size 24 free'd
==1048== at 0x4C2C13B: free (vg_replace_malloc.c:530)
==1048== by 0x15ED03: l_free (util.c:136)
==1048== by 0x1603C4: l_queue_destroy (queue.c:83)
==1048== by 0x134BD5: eap_secret_request_free (network.c:719)
==1048== by 0x134EF9: eap_send_agent_req (network.c:817)
==1048== by 0x1352F7: network_connect_8021x (network.c:936)
==1048== by 0x1354C4: network_connect (network.c:987)
==1048== by 0x178DD2: _dbus_object_tree_dispatch (dbus-service.c:1690)
==1048== by 0x16D32A: message_read_handler (dbus.c:285)
==1048== by 0x166EC3: io_callback (io.c:123)
==1048== by 0x165A1A: l_main_iterate (main.c:376)
==1048== by 0x165B58: l_main_run (main.c:423)
In eap_check_settings move the check for the EAP-Identity setting so
that the method's check_setting call back has a chance to request it
from the agent. Note the check can be also moved to the EAP methods
so that they are free to skip it if not NULL identity is ok.
Replace usages of l_settings_get_value with l_settings_get_string, which
will make sure the returned strings are unescaped but also allocates
memeory and forces us to use l_free on most of the strings. Some of
these strings we explicitly set with l_settings_set_string() in our code
so when we retrieved them with l_settings_get_value() we would receive a
different string if there were any escapable characters in the string.
I didn't replace any of the l_settings_get_value() uses where we're just
checking whether a setting is present, or those which are hexstrings or
EAP method names assuming that they can't have any special characters,
although this isn't future proof. I did use l_settings_get_string() for
file paths though.
Accept two setting IDs in eap_append_secret, first for the username and
second for the password in case of the EAP_SECRET_REMOTE_USER_PASSWORD
EAP secret type. In all other cases only the first setting is used.
Until now for EAP_SECRET_REMOTE_USER_PASSWORD secrets we'd generate the
two setting names by adding different suffixes to the ID parameter.
Using the two different setting names automatically fixes the issues
with using the EAP Identity returned by the agent in EAP-MSCHAPv2 and
EAP-PWD.
The WDS dbus property of a Device directly maps to the 4ADDR property
of a real netdevice. It can be activated or deactivated at any point
in time.
The name WDS comes from the fact that this feature allows a STA
interface to be bridged and thus create a Wireless Distribution
System (the same name is used in OpenWRT and hostapd).
To implement this feature, the 'powered callback' data structure has
been renamed and re-used.
When a wifi interface is added/removed to/from a bridge, a
RTM_NEW/DELLINK event is issued. This is the same event used to signal
when an interface is created/deleted.
For this reason the event generated by the bridge code has to be
properly distinguished and handled accordingly. Failing to do so will
result in inconsistencies in iwd which will think an interface has been
deleted when it was actually not.
Detect incoming NEW/DELLINK bridge events and reacts accordingly. For
now, this simply means printing a simple message, as there is no
special logic in iwd for this yet.
This is meant to reset the EAP state back to its original state without
affecting any state variables obtained through load_settings. This can
be useful for EAP Reauthentication triggered by the AP.
Instead use '-d' command line option. This option uses an optional
argument. Without an argument, '*' is assumed. Otherwise you can
specify a glob string to match. Any debug output that matches the glob
string will be printed. e.g.:
src/iwd -d '*eap*'
Some EAP servers might try to send us packets after the EAP connection
has been established. When EAP succeeds we destroy the EAP object. If
a new EAP request arrives we create a temporary EAP object to handle the
request (most likely to NAK it). However, if the packet is not destined
to a particular method (e.g. it is a notification) the current logic can
result in a crash.
src/netdev.c:netdev_set_gtk() 3
==4300== Invalid read of size 8
==4300== at 0x14204B: __eap_handle_request (eap.c:203)
==4300== by 0x142339: eap_rx_packet (eap.c:287)
==4300== by 0x12AEF9: eapol_rx_packet (eapol.c:1622)
==4300== by 0x12BBBC: __eapol_rx_packet (eapol.c:2018)
==4300== by 0x116D1E: netdev_pae_read (netdev.c:3121)
==4300== by 0x16672B: io_callback (io.c:123)
==4300== by 0x165239: l_main_iterate (main.c:376)
==4300== by 0x16537D: l_main_run (main.c:423)
==4300== by 0x10F95C: main (main.c:447)
==4300== Address 0x30 is not stack'd, malloc'd or (recently) free'd
==4300==
When the server sends an identity prompt or a notification, we were
trying to print from our local buffer, not from the actual packet. The
relevant valgrind trace is:
src/netdev.c:netdev_mlme_notify() MLME notification 64
==4300== Conditional jump or move depends on uninitialised value(s)
==4300== at 0x4C3006E: strnlen (vg_replace_strmem.c:425)
==4300== by 0x508C513: vfprintf (vfprintf.c:1643)
==4300== by 0x508EB75: buffered_vfprintf (vfprintf.c:2329)
==4300== by 0x508C1A1: vfprintf (vfprintf.c:1301)
==4300== by 0x167051: log_stderr (log.c:145)
==4300== by 0x16756E: l_log_with_location (log.c:293)
==4300== by 0x142173: __eap_handle_request (eap.c:235)
==4300== by 0x142339: eap_rx_packet (eap.c:287)
==4300== by 0x12AEF9: eapol_rx_packet (eapol.c:1622)
==4300== by 0x12BBBC: __eapol_rx_packet (eapol.c:2018)
==4300== by 0x116D1E: netdev_pae_read (netdev.c:3121)
==4300== by 0x16672B: io_callback (io.c:123)
==4300==
EAP identity prompt: ""
GLIBC is not necessarily the only library that provides execinfo.
With libexecinfo execinfo can be used also in other Libraries.
The patch lets the configure check the existence of the header
and the libexecinfo Library and uses them if avaible.
(also fixes compilation if execinfo is not avaible)
iwd was auto-connecting to the open networks despite having
Autoconnect=false flag set in the network configuration file.
This patch enables iwd to load the configuration files for the
open networks during the auto-connect attempt to take advantage
of the Autoconnect flag.
EAP-PWD was hard coded to only work on LE architectures. This
adds 2 conversion functions to go from network byte order (BE)
to any native architecture, and vise versa.
The file, src/ecc.c was taken from the bluez project:
https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/src/shared/ecc.c
There were minor changes made, e.g. changing some functions to globals
for access in EAP-PWD as well as removing some unneeded code. There was
also some code appended which allows for point addition, modulus inverse
as well as a function to compute a Y value given an X.
If Control Port over NL80211 is not supported, open up a PAE socket and
stuff it into an l_io on the netdev object. Install a read handler on
the l_io and call __eapol_rx_packet as needed.
With the introduction of Control Port Over NL80211 feature, the
transport details need to be moved out of eapol and into netdev.c.
Whether a given WiFi hardware supports transfer of Control Port packets
over NL80211 is Wiphy and kernel version related, so the transport
decisions need to be made elsewhere.
On connect add any secrets we've received through the agent to the
l_settings objects which the EAP methods will process in load_settings.
The settings object is modified but is never written to storage. If
this was to change because some settings need to be saved to storage,
a new l_settings object might be needed with the union of the settings
from the file and the secrets so as to avoid saving the sensitive data.
These EAP methods do not store the identity inside the settings file
since it is obtained from the SIM card, then provided to IWD via
get_identity method. If the get_identity method is implemented, do
not fail the settings check when EAP-Identity is missing.
Use eap_check_settings directly from network.c before we start the
connection attempt at netdev.c level, to obtain all of the required
passwords/passphrases through the agent. This is in network.c because
here we can decide the policies for whether to call the agent in
autoconnect or only if we had a request from the user, also whether we
want to save any of that for later re-use (either password data or
kernel-side key serial), etc.
In this patch we save the credentials for the lifetime of the network
object in memory, and we skip the network if it requires any passphrases
we don't have while in autoconnect, same as with PSK networks where the
PSK isn't given in the settings. Note that NetworkManager does pop up
the password window for PSK or EAP passwords even in autoconnect.
If EAP needs multiple passwords we will call the agent sequentially for
each.
Confirm that the PEM file paths that we'll be passing to the l_tls
object are loading Ok and request/validate the private key passphrase
if needed. Then also call eap_check_settings to validate the inner
method's settings.
Confirm that the PEM file paths that we'll be passing to the l_tls
object are loading Ok and request/validate the private key passphrase
if needed. Then also call eap_check_settings to validate the inner
method's settings.
With the goal of requesting the required passwords/passphrases, such as
the TLS private key passphrase, from the agent, add a static method
eap_check_settings to validate the settings and calculate what passwords
are needed for those settings, if any. This is separate from
eap_load_settings because that can only be called later, once we've
got an eap state machine object. We need to get all the needed EAP
credentials from the user before we even start connecting.
While we do this, we also validate the settings and output any error
messages through l_error (this could be changed so the messages go
somewhere else in the future), so I removed the error messages from
eap_load_settings and that method now assumes that eap_check_settings
has been called before.
eap_check_settings calls the appropriate method's .check_settings method
if the settings are complete enough to contain the method name. The
policy is that any data can be provided inside the l_settings object
(from the network provisioning/config file), but some of the more
sensitive fields, like private key passwords, can be optionally omitted
and then the UI will ask for them and iwd will be careful with
caching them.
Within struct eap_secret_info, "id" is mainly for the EAP method to
locate the info in the list. "value" is the actual value returned
by agent. "parameter" is an optional string to be passed to the agent.
For a private key passphrase it may be the path to the key file, for a
password it may be the username for which the password is requested.
In agent_receive_reply we first call the callback for the pending
request (agent_finalize_pending) then try to send the next request
in the queue. Check that the next request has not been sent already
which could happen if it has been just queued by the callback.
The difference in the handlers was that in the
NETDEV_EVENT_DISCONNECT_BY_AP case we would make sure to reply
to a pending dbus Connect call. We also need to do that for
NETDEV_EVENT_DISCONNECT_BY_SME. This happens if another process
sends an nl80211 disconnect command while we're connecting.
The eapol handshake timeout can now be configured in main.conf
(/etc/iwd/main.conf) using the key eapol_handshake_timeout. This
allows the user to configure a long timeout if debugging.
After an EAP exchange rsn_info would be uninitialized and in the FT case
we'd use it to generate the step 2 IEs which would cause an RSNE
mismatch during FT handshake.
Until now we'd save the second 32 bytes of the MSK as the PMK and use
that for the PMK-R0 as well as the PMKID calculation. The PMKID
actually uses the first 32 bytes of the PMK while the PMK-R0's XXKey
input maps to the second 32 bytes. Add a pmk_len parameter to
handshake_state_set_pmk to handle that. Update the eapol_eap_results_cb
802.11 quotes to the 2016 version.
handshake_state_install_ptk triggers a call to
netdev_set_pairwise_key_cb which calls netdev_connect_ok, so don't call
netdev_connect_ok after handshake_state_install_ptk. This doesn't fix
any specific problem though.
If the request being cancelled by agent_request_cancel has already been
sent over dbus we need to reset pending_id, the timeout, call l_dbus_cancel
to avoid the agent_receive_reply callback (and crash) and perhaps start
the next request. Alternatively we could only reset the callback and not
free the request, then wait until the agent method to return before starting
the next request.
Move the cancelling of the eapol timeout from the end of step 1 to
step 3 to guard the whole handshake. At the end of step 1 stop the
EAPOL-Start timeout for the case of 802.1X authentication + a cached
PMKSA (not used yet.)
Some APs respond to Neighbor Report Requests with neighbor reports that
have a zero operating class value and a non-zero channel number. This
does not mean that the channel is in the same band that the reporting
AP operates in. Try to guess the band that the channel refers to out of
2.4 and 5GHz -- the bands supported by those APs.
wpa_supplicant also has this workaround in place.
SA Query procedure is used when an unprotected disassociate frame
is received (with frame protection enabled). There are two code
paths that can occur when this disassociate frame is received:
1. Send out SA Query and receive a response from the AP within a
timeout. This means that the disassociate frame was not sent
from the AP and can be ignored.
2. Send out SA Query and receive no response. In this case it is
assumed that the AP went down ungracefully and is now back up.
Since frame protection is enabled, you must re-associate with
the AP.
1. Enforce implementation of handle_request function
2. In case of unimplemented handle_retransmit try to use
handle_request instead and rely on method specific
mechanism to restart the conversation if necessary
3. Make method->free implementation unrequired
When we call scan_periodic_stop and a periodic scan is in progress (i.e.
the trigger callback has been called already) we get no new callback
from scan.c and the device Scanning property remains True forever so set
it to False.
The change from scan_periodic_stop to periodic_scan_stop looks silly but
it's consistent with our naming :)
This patch adds a watcher/parser for the frame event associated with
an AP directed BSS transition (AP roaming). When the AP sends a BSS
transition request, this will parse out the BSS candidate list
(neighbor report) and initiate a roam scan. After this point the
existing roaming code path is reused.
The identity retrieved from simauth was required to include the
prefix for SIM/AKA/AKA', but in reality a real SIM would not
include that prefix in the IMSI. Now the correct prefix is
prepended onto the identity depending on the EAP method.
If the SQN in AUTN is incorrect the simauth module will return
the AUTS parameter, which is sent back to the server and the
servers SQN number is updated.
Forcing a plugin to create and register simauth at once is sometimes
inconvenient. This patch separates the creation and registration
into two API's, and also adds several others to add the required simauth
data incrementally (identity, driver data, sim/aka support). This also
allows for the driver to unregister the auth provider without freeing
up the simauth object itself e.g. if the driver temporarily becomes
unavailable, but will come back sometime in the future.
The simauth watch API's were also renamed. Watchers will now get a
callback when the provider has been unregistered, so they have been
renamed to sim_auth_unregistered_watch_[add|remove].
src/simauth.c:163:6: error: no previous declaration for ‘sim_auth_cancel_request’ [-Werror=missing-declarations]
void sim_auth_cancel_request(struct iwd_sim_auth *auth, int id)
^~~~~~~~~~~~~~~~~~~~~~~
iwd now supports plugin loading, whitelisting and blacklisting. Both
the whitelist and the blacklist support multiple patterns separated by a
',' character.
Make sure device->autoconnect is set when entering the autoconnect state
after netdev UP event. Otherwise the next time
device_set_autoconnect(device, false) is called it will exit early seeing
that device->autoconnect is false and not switch the device state.
This is the core module that takes care of registering
authentication drivers. EAP-SIM/AKA will be able to acquire
a driver that supports the required algorithms. The driver
implementation (hardcoded/ofono etc.) is isolated into
separate plugin modules.
EAP-SIM/AKA/AKA' retrieve the EAP-Identity off the SIM card
not from the settings file. This adds a new EAP method API
which can optionally be implemented to retrieve the identity.
If get_identity is implemented, the EAP layer will use it to
retrieve the identity rather than looking in the settings file.
network_settings_load expects NULL value to be returned
on failed attempts to read the settings files inside of
storage_network_open. At the same time storage_network_open
used to always return an initialized l_settings
structure despite the outcome of the read operations,
indicating a success.
When the 4-Way Handshake is done eapol.c calls netdev_set_tk, then
optionally netdev_set_gtk and netdev_set_igtk. To support the no group
key option send the final SET STATION enabling the controlled port
inside the callback for the netdev_set_tk operation which always means
the end of a 4-Way Handshake rather than in the netdev_set_gtk callback.
The spec says exactly that the controlled port is enabled at the end of
the 4-Way Handshake.
The netlink operations will still be queued in the same order because
the netdev_set_tk/netdev_set_gtk/netdev_set_igtk calls happen in one
main loop iteration but even if the order changed it wouldn't matter.
On failure of any of the three operations netdev_setting_keys_failed
gets called and the remaining operations are cancelled.
Track the contents and size of the GTK and IGTK and if the Authenticator
(or an adversary) tries to set the same GTK/IGTK, process the packet
normally but do not resubmit the GTK/IGTK to the kernel.
GTK KDE was being checked for being a minimum of 6 bytes. Not quite
sure why since the minimum GTK key length is 16 bytes for CCMP.
Similarly make sure that the maximum length is not more than 32, which
is currently the largest key size (TKIP)
This is a bizarre case since MIC calculation succeeded for the incoming
packet. But just in case MIC calculation fails for the outgoing packet,
kill the handshake.
The comments quoted sections of the specification that indicated STA
behavior for verifying Message 3 of 4 or GTK 1 of 2. But in reality the
code directly below simply calculated the MIC for Message 4 of 4 or GTK
2 of 2.
Use eapol_frame_watch_add/eapol_frame_watch_remove in eapol_sm, while
there simplify the early_frame logic and confirm sender address for
received frames.
Set all the new field values into struct sta_state only after all the
error checks for better readabilty and fixing a possible issue if we
did "sta->rates = rates" and then detected en error and freed "rates".
Also update a comment which I think used the wording from 802.11-2012
instead of 802.11-2016.
DEL_KEY is not needed and will return errors right after NEW_STATION or
right after DEL_STATION. In both cases the kernel makes sure there are
no old keys for the station already.
As a temporary DBus API to switch between Station and Access Point
modes, add two methods on the Device interface. Add a new state
DEVICE_STATE_ACCESS_POINT which is in effect from the moment
StartAccessPoint is received (even before it returns) until
StopAccessPoint returns, there are no intermediate states when the
methods run for simplicity. Add checks across device.c to make sure
Station related functionality is disabled when in Access Point mode.
Add a utility to append a KDE to the key_data field in an EAPoL frame.
The KDE types enum is actually added to handshake.h because we've got
the utilities for finding those KDEs in a buffer there. The new
function is specific to EAPoL-Key frames though and perhaps to simple to
be split across handshake.c and eapol.c. Also it didn't seem useful to
use the ie_tlv_builder here.
Parse Association Request frames and send Association Responses, handle
Disassociation. With this we should be able to receive uncontrolled
port data frames since we register the STAs with the kernel.
In this version I don't register for Reassociation frames.
Validate the IE order for some of the cases. For other cases, as with
the Disassociation, Deauthentication and Action frame types in section
9.3 it's not even clear from the spec the fields are expected to be IEs
(in fact for Action frame we know they aren't). For the Shared Key
authentication type drop the union with the contents as they can be
easier parsed as an IE sequence. For SAE we are not expecting an IE
sequence apparently so this is where the union could come useful but
let's leave that until we want to support SAE.
Check the IE order for each frame type where we'd just do the body
minimum length check until now (and not always correctly). We do not
try to validate the contents of any IEs (may be doable for some) or the
minimum mandatory IEs presence. This is because which IEs are required
depend on the contents of other fields in the frame, on the
authentication state and STA config and even contents of a request frame
which we're validating the response to. Frame handlers have to do this
work anyway.
Declare the two missing frame subtype enum values for Action frames,
assume Action frames are valid. Once we have specific validation code
for any Action frames elsewhere, we can move it to mpdu_validate, but
right don't try to validate the frame body as there are many subtypes
and we don't use any of them except Neighbor Reports which are actually
really simple.
Since we use the special 0xffff value in the builder code, check that
the tag is not 0xffff in ie_tlv_builder_finalize before writing the
header. This is for consistency, not for a specific use case.
Make parsing TLVs using Extended Element IDs easier by returning the
extended tag value as listed in enum ie_type instead of just the 255
value, and not returning the pointer to the extended tag as the IE data
and instead the pointer to the next byte after the extended ID.
The l_queue_find() to find other watches matching the new prefix
needs to be before the watchlist_link(), otherwise the prefix will
match itself and "registered" is always true.
In WATCHLIST_NOTIFY_MATCHES pass pointer to the item instead of
item->notify_data to free item->notify_data to be the final watch user's
user_data. This is also what netdev expects.
The EAP-method's .probe methods only checked the method name so do that
in eap.c instead and allocate method state in .load_settings. Rename
method's .remove method to .free to improve the naming.
This can be used to selectively notify watchlist items. The match
function is called for each watchlist_item and match_data is passed
along. If the match function returns true, then the watch_item is
notified. The match function signature and semantics are identical
to l_queue_match_func_t.
Rename netdev_register_frame to netdev_frame_watch_add and expose to be
usable outside of netdev.c, add netdev_frame_watch_remove also. Update
the Neighbor Report handling which was the only user of
netdev_register_frame.
The handler is now simpler because we use a lookup list with all the
prefixes and individual frame handlers only see the frames matching the
right prefix. This is also useful for the future Access-Point mode.
src/mpdu.c: In function ‘mpdu_validate’:
src/mpdu.c:180:9: error: ‘mmpdu’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
mmpdu = (const struct mmpdu_header *) mmpdu;
^
Refactor management frame structures to take into account optional
presence of some parts of the header:
* drop the single structure for management header and body since
the body offset is variable.
* add mmpdu_get_body to locate the start of frame body.
* drop the union of different management frame type bodies.
* prefix names specific to management frames with "mmpdu" instead
of "mpdu" including any enums based on 802.11-2012 section 8.4.
* move the FC field to the mmpdu_header structure.
This EAP method uses nearly all the logic from EAP-AKA. The major
difference is it uses the new key derivation functions for AKA' as
well as the SHA256 MAC calculation.
EAP-AKA' uses SHA256 rather than SHA1 to generate the packet MAC's.
This updates the derive MAC API to take the EAP method type and
correctly use the right SHA variant to derive the MAC.
This is the core key generation code for the AKA' method which
follows RFC 5448. Two new functions are implemented, one for
deriving CK'/IK' and the other for deriving the encryption keys
using CK'/IK'.
If the kernel device driver or the kernel nl80211 version doesn't
support the new RSSI threshold list CQM monitoring, implement similar
logic in iwd with periodic polling. This is only active when an RSSI
agent is registered to receive the events. I tested this with the same
testRSSIAgent autotests that tests the driver-side rssi monitoring
except with all timeouts multiplied by ~20.
The AT_VERSION_LIST attribute length was not being properly
checked. The actual length check did not include possible padding
bytes, so align_len() was added to ensure it was padded properly.
The comment about the padding being included in the Master Key
generation was not correct (padding is NOT included), and was removed.
Function to allow netdev.c to explicitly tell eapol.c whether to expect
EAP / 4-Way handshake. This is to potentially make the code more
descriptive, until now we'd look at sm->handshake->ptk_complete to see
if a new PTK was needed.
A 4-Way handshake is required on association to an AP except after FT.
Modify netdev_get_iftype, which was until now unused, and add
netdev_set_iftype. Don't skip interfaces with types other than STATION
on startup, instead reset the type to STATION in device.c.
netdev_get_iftype is modified to use our own interface type enum to
avoid forcing users to include "nl80211.h".
Note that setting an interface UP and DOWN wouldn't generally reset the
iftype to STATION. Another process may still change the type while iwd
is running and iwd would not detect this as it would detect another
interface setting interface DOWN, not sure how far we want to go in
monitoring all of the properties this way.
If we're adding the BSS to the list only because it is the current BSS,
set the rank to 0 (lowest possible value) in case the list gets used in
the next Connect call.
Allow attempts to connect to a new AP using the Reassociation frame even
if netdev->operational is false. This is needed if we want to continue
an ongoing roam attempt after the original connection broke and will be
needed when we start using cached PMKSAs in the future.
Use beacon loss event to trigger a roam attempt in addition to the RSSI
monitoring. Due to the how well beacons are normally received compared
to data packets, a beacon loss indicates a serious problem with the
connection so act as soon as a first beacon loss event is seen.
Avoid roaming methods that involve the current AP: preauthentication,
neighbor report request and FT-over-the-DS (not supported)
There are situations including after beacon loss and during FT where the
cfg80211 will detect we're now disconnected (in some cases will send a
Deauthenticate frame too) and generate this event, or the driver may do
this. For example in ieee80211_report_disconnect in net/mac80211/mlme.c
will (through cfg80211) generate a CMD_DEAUTHENTICATE followed by a
CMD_DISCONNECT.
The kernel doesn't reset the netdev's state to disconnected when it
sends us a beacon loss event so we can't either unless we automatically
send a disconnect command to the kernel.
It seems the handling of beacon loss depends on the driver. For example
in mac80211 only after N beacon loss events (default 7) a probe request is
sent to the AP and a deauthenticate packet is sent if no probe reply is
receiver within T (default 500ms).
If an application initiates the Connect() operation and
that application has an agent registered, then that
application's agent will be called. Otherwise, the default
agent is called.
==40686== Syscall param sendmsg(msg.msg_iov[0]) points to uninitialised byte(s)
==40686== at 0x5147037: sendmsg (in /usr/lib64/libc-2.24.so)
==40686== by 0x43957C: operate_cipher (cipher.c:354)
==40686== by 0x439C18: l_cipher_decrypt (cipher.c:415)
==40686== by 0x40FAB8: arc4_skip (crypto.c:181)
Initialize the skip buffer to 0s. This isn't strictly necessary, but
hides the above valgrind warning.
The aim of arc4 skip is simply to seed some data into the RC4 cipher so
it makes it harder for the attacker to decrypt. This 'initialization'
doesn't really care what data is fed.
CMD_DEAUTHENTICATE is not available for FullMAC based cards. We already
use CMD_CONNECT in the non-FT cases, which works on all cards. However,
for some reason we kept using CMD_DEAUTHENTICATE instead of CMD_DISCONNECT.
For FT (error) cases, keep using CMD_DEAUTHENTICATE.
Certain WiFi drivers do not support using CMD_SET_STATION (e.g.
mwifiex). It is not completely clear how such drivers handle the
AUTHORIZED state, but they don't seem to take it into account. So for
such drivers, ignore the -ENOTSUPP error return from CMD_SET_STATION.
These flags are documented in RFC2863 and kernel's
Documentation/networking/operstates.txt. Operstate doesn't have any
siginificant effect on normal connectivity or on our autotests because
it is not used by the kernel except in some rare cases but it is
supposed to affect some userspace daemons that watch for RTM_NEWLINK
events, so I believe we *should* set them according to this
documentation. Changes:
* There's no point setting link_mode or operstate of the netdev when
we're bringing the admin state DOWN as that overrides operstate.
* Instead of numerical values for link_mode use the if.h defines.
* Set IF_OPER_UP when association succeeds also in the Fast Transition
case. The driver will have set carrier off and then on so the
operstate should be IF_OPER_DORMANT at this point and needs to be
reset to UP.
Allow registering and unregistering agent object to receive RSSI level
notifications. The methods are similar to the ones related to the
password agent, including a Release method for the agent.
Add an methods and an event using the new
NL80211_EXT_FEATURE_CQM_RSSI_LIST kernel feature to request RSSI
monitoring with notifications only when RSSI moves from one of the N
intervals requested to another.
device.c will call netdev_set_rssi_report_levels to request
NETDEV_EVENT_RSSI_LEVEL_NOTIFY events every time the RSSI level changes,
level meaning one of the intervals delimited by the threshold values
passed as argument. Inside the event handler it can call
netdev_get_rssi_level to read the new level.
There's no fallback to periodic polling implemented in this patch for
the case of older kernels and/or the driver not supporting
NL80211_EXT_FEATURE_CQM_RSSI_LIST.
==27901== Conditional jump or move depends on uninitialised value(s)
==27901== at 0x41157A: handshake_util_find_pmkid_kde
(handshake.c:537)
==27901== by 0x40E03A: eapol_handle_ptk_1_of_4 (eapol.c:852)
==27901== by 0x40F3CD: eapol_key_handle (eapol.c:1417)
==27901== by 0x40F955: eapol_rx_packet (eapol.c:1607)
==27901== by 0x410321: __eapol_rx_packet (eapol.c:1915)
Agent implementation inside agent.c takes a reference of the trigger
message associated with the request. When the callback is called, the
message is passed as an argument. The callback is responsible for
taking the message reference if necessary. Once the callback returns,
agent releases its reference.
For error paths, our code was using dbus_pending_reply which in turn
uses dbus_message_unref. This caused the agent to try an unref
operation on an already freed object.
Move the calling of the *_shutdown functions from the signal handler to
a new public function, and use that function inside the DBus disconnect
handler to make sure resources are cleanly released.
Skip the matching of the PMKID KDE to the PMKID list in the RSNE if
we've seen a new EAP authentication before the step 1/4 was received.
That would mean that the server had not accepted the PMKIDs we submitted
and we performed a new 8021X authentication, producing a new PMKSA which
won't be on the list in the RSNE.
Currently we'd send EAPOL-Start whenever EAP was configured and we
received an EAPOL-Key before EAP negotiation. Instead only do that if
we know we can't respond to the 4-Way handshake because we don't have
a PMK yet or the PMKID doesn't match. Require a PMKID in step 1/4 if
we'd sent a list of PMKIDs in our RSNE.
Modify the packet filter to also accept frames with ethertype of 0x88c7
and pass the ethertype value to __eapol_rx_packet so it can filter out
the frames where this value doesn't match the sm->preauth flag.
Add a wrapper for eapol_start that sets the sm->preauth flag and sends
the EAPOL-Start frame immediately to skip the timeout since we know
that the supplicant has to initiate the authentication.
Use netdev_reassociate if FT is not available. device_select_akm_suite
is only moved up in the file and the reused code from device_connect is
moved to a separate function.
netdev_reassociate transitions to another BSS without FT. Similar to
netdev_connect but uses reassociation instead of association and
requires and an existing connection.
Pass an additional parameter to the scan results notify functions to
tell them whether the scan was successful. If it wasn't don't bother
passing an empty bss_list queue, pass NULL as bss_list. This way the
callbacks can tell whether the scan indicates there are no BSSes in
range or simply was aborted and the old scan results should be kept.
++++++++ backtrace ++++++++
0 0x7fc0b20ca370 in /lib64/libc.so.6
1 0x4497d5 in l_dbus_message_new_error_valist() at /home/denkenz/iwd/ell/dbus-message.c:372
2 0x44994d in l_dbus_message_new_error() at /home/denkenz/iwd/ell/dbus-message.c:394
3 0x41369b in dbus_error_not_supported() at /home/denkenz/iwd/src/dbus.c:148
4 0x40eaf5 in device_connect_network() at /home/denkenz/iwd/src/device.c:1282
5 0x41f61c in network_autoconnect() at /home/denkenz/iwd/src/network.c:424
6 0x40c1c1 in device_autoconnect_next() at /home/denkenz/iwd/src/device.c:172
7 0x40cabf in device_set_scan_results() at /home/denkenz/iwd/src/device.c:368
8 0x40cb06 in new_scan_results() at /home/denkenz/iwd/src/device.c:376
9 0x41be8a in scan_finished() at /home/denkenz/iwd/src/scan.c:1021
10 0x41bf9e in get_scan_done() at /home/denkenz/iwd/src/scan.c:1048
11 0x43d5ce in destroy_request() at /home/denkenz/iwd/ell/genl.c:136
12 0x43ded1 in process_unicast() at /home/denkenz/iwd/ell/genl.c:395
13 0x43e295 in received_data() at /home/denkenz/iwd/ell/genl.c:502
14 0x43aa62 in io_callback() at /home/denkenz/iwd/ell/io.c:120
15 0x439632 in l_main_run() at /home/denkenz/iwd/ell/main.c:375 (discriminator 2)
16 0x403074 in main() at /home/denkenz/iwd/src/main.c:261
17 0x7fc0b20b7620 in /lib64/libc.so.6
Also handle the case of a periodic scan when handling a
NL80211_CMD_SCAN_ABORTED. The goal is to make sure the supplied callback
is always called if .trigger was called before, but this should also fix
some other corner cases.
* I add a sp.triggered field for periodic scans since sc->state doesn't
tell us whether the scan in progress was triggered by ourselved o
someone else (in that case .trigger has not been called)
* Since the NL80211_CMD_SCAN_ABORTED becomes similar to get_scan_done I
move the common code to scan_finished
* I believe this fixes a situation where we weren't updating sc->state
if we'd not triggered the scan, because both get_scan_done and the
NL80211_CMD_SCAN_ABORTED would return directly.
If the current request is not freed when we receive the
NL80211_CMD_SCAN_ABORTED event, device.c will keep thinking that
we're still scanning and the scan.c logic also gets confused and may
resend the current request at some point and call sr->trigger again
causing a segfault in device.c.
I pass an empty bss_list to the callback, another possibility would be
to pass NULL to let the callback know not to replace old results yet.
The callbacks would need to handle a NULL first.
Handle the changes of interface address in RTNL New Link messages
similarly to the name changes, emit a NETDEV_WATCH_EVENT_ADDRESS_CHANGE
event and a propety change on dbus.
Note this can only happen when the interface is down so it doesn't
break anything but we need to handle it anyway.
DBus has certain rules on what constitutes a valid path. Since the
wiphy name is freeform, it is possible to set it such that the contents
do not contain a valid path.
We fall back to simply using the wiphy index as the path.
DBus strings must be valid utf8. The kernel only enforces that the
wiphy name is null terminated string. It does not validate or otherwise
check the contents in any way. Thus it is possible to have
non-printable or non-utf8 characters inside.
NL80211_CMD_SET_WIPHY can be used to set various attributes on the wiphy
object in the kernel. This includes ATTR_WIPHY_NAME among others. iwd
currently does not parse or store any of the other attributes, so we
react to changes in WIPHY_NAME only.
The wiphy attribute should never be repeated by the kernel, so this
check is ultimately not needed. This condition can also be easily
checked by looking at the iwmon output in case things do go terribly
wrong.
Fix 1a64c4b771 by setting use_eapol_start
by default only when 8021x authentication is configured. Otherwise we'd
be sending EAPOL-Start even for WPA2 Personal possibly after the 4-Way
Handshake success.
This implements very initial support of WPS PIN based connections. The
scanning logic attempts to find an AP in PIN mode and tries to connect
to that AP. We currently do not try multiple APs if available or
implement the WSC 1.0 connection logic.
Right now the code checks for is_rsn to wait for the 4-way handshake and
sends the NETDEV_EVENT_4WAY_HANDSHAKE. However, is_rsn condition is not
true for WSC connections since they do not set an RSN field. Still,
they are EAP based handshakes and should be treated in the same manner.
We relax the is_rsn check to instead check for netdev->sm. Currently
netdev->sm is only non-NULL if handshake->own_ie field is not NULL or in
the case of eap-wsc connections.
Define minimum delay between roam attempts and add automatic retries.
This handles a few situations:
* roam attempt failing, then RSSI going above the threshold and below
again -- in that case we don't want to reattempt too soon, we'll only
reattempt after 60s.
* roam attempt failing then RSSI staying low for longer than 60 -- in
that case we want to reattempt after 60s too.
* signal being low from the moment we connected -- in that case we also
want to attempt a roam every some time.
Fix a leak of the MDE buffer. It is now only needed for the single call
to handshake_state_set_mde which copies the bytes anyway so use a buffer
on stack.
Since caab23f192085e6c8e47c41fc1ae9f795d1cbe86 hostapd is going to set
this bit to zero for RSN networks but both values will obviously be in
use. Only check the value if is_wpa is true - in this case check the
value is exactly 16, see hostapd commit:
commit caab23f192085e6c8e47c41fc1ae9f795d1cbe86
Author: Jouni Malinen <j@w1.fi>
Date: Sun Feb 5 13:52:43 2017 +0200
Set EAPOL-Key Key Length field to 0 for group message 1/2 in RSN
P802.11i/D3.0 described the Key Length as having value 16 for the group
key handshake. However, this was changed to 0 in the published IEEE Std
802.11i-2004 amendment (and still remains 0 in the current standard IEEE
Std 802.11-2016). We need to maintain the non-zero value for WPA (v1)
cases, but the RSN case can be changed to 0 to be closer to the current
standard.
Add sr NULL check before accessing sr->id. Call scan_request_free on
request structure and call the destroy callback. Cancel the netlink
TRIGGER_SCAN command if still running and try starting the next scan
in the queue. It'll probably still fail with EBUSY but it'll be
reattempted later.
Always call start_next_scan_request when a scan request has finished,
with a success or a failure, including a periodic scan attempt. Inside
that function check if there's any work to be done, either for one-off
scan requests or periodic scan, instead of having this check only inside
get_scan_done. Call start_next_scan_request in scan_periodic_start and
scan_periodic_timeout.
Also call the trigger callback with an error code when sending the
netlink command fails after the scan request has been queued because
another scan was in progress when the scan was requested.
Program received signal SIGSEGV, Segmentation fault.
0x0000000000419d38 in scan_done (msg=0x692580, userdata=0x688250)
at src/scan.c:250
250 sc->state = sr->passive ? SCAN_STATE_PASSIVE : SCAN_STATE_ACTIVE;
(gdb) bt
0 0x0000000000419d38 in scan_done (msg=0x692580, userdata=0x688250)
at src/scan.c:250
1 0x000000000043cac0 in process_unicast (genl=0x686d60, nlmsg=0x7fffffffc3b0)
at ell/genl.c:390
2 0x000000000043ceb0 in received_data (io=0x686e60, user_data=0x686d60)
at ell/genl.c:506
3 0x000000000043967d in io_callback (fd=6, events=1, user_data=0x686e60)
at ell/io.c:120
4 0x000000000043824d in l_main_run () at ell/main.c:381
5 0x000000000040303c in main (argc=1, argv=0x7fffffffe668) at src/main.c:259
The reasoning is that the logic inside scan_common is reversed. Instead
of freeing the scan request on error, we always do it. This causes the
trigger_scan callback to receive invalid userdata.
Save the ids of the netlink trigger scan commands that we send and
cancel them in scan_ifindex_remove to fix a race leading to a
segfault. The segfault would happen every time if scan_ifindex_remove
was called in the same main loop iteration in which we sent the
command, on shutdown:
^CTerminate
src/netdev.c:netdev_free() Freeing netdev wlan3[6]
src/device.c:device_disassociated() 6
src/device.c:device_enter_state() Old State: connected, new state:
disconnected
src/device.c:device_enter_state() Old State: disconnected, new state:
autoconnect
src/scan.c:scan_periodic_start() Starting periodic scan for ifindex: 6
src/device.c:device_free()
src/device.c:bss_free() Freeing BSS 02:00:00:00:00:00
src/device.c:bss_free() Freeing BSS 02:00:00:00:01:00
Removing scan context for ifindex: 6
src/scan.c:scan_context_free() sc: 0x5555557ca290
src/scan.c:scan_notify() Scan notification 33
src/netdev.c:netdev_operstate_down_cb() netdev: 6, success: 1
src/scan.c:scan_periodic_done()
src/scan.c:scan_periodic_done() Periodic scan triggered for ifindex:
1434209520
Program received signal SIGSEGV, Segmentation fault.
0x0000000000000064 in ?? ()
(gdb) bt
#0 0x0000000000000064 in ?? ()
#1 0x0000555555583560 in process_unicast (nlmsg=0x7fffffffc1a0,
genl=0x5555557c1d60) at ell/genl.c:390
#2 received_data (io=<optimized out>, user_data=0x5555557c1d60)
at ell/genl.c:506
#3 0x0000555555580d45 in io_callback (fd=<optimized out>,
events=1, user_data=0x5555557c1e60) at ell/io.c:120
#4 0x000055555558005f in l_main_run () at ell/main.c:381
#5 0x00005555555599c1 in main (argc=<optimized out>, argv=<optimized out>)
at src/main.c:259
Parse the contents of the GTK and IGTK subelements in an FT IE instead
of working with buffers containing the whole subelement. Some more
validation of the subelement contents. Drop support for GTK / IGTK when
building the FTE (unused).
Don't start the handshake timeout in eapol_start if either
handshake->ptk_complete is set (handshake already done) or
handshake->have_snonce is set (steps 1&2 done). This accounts for
eapol_start being called after a Fast Transition when a 4-Way handshake
is not expected.
Add a flush flag to scan_parameters to tell the kernel to flush the
cache of scan results before the new scan. Use this flag in the
active scan during roaming.
Split the igtk parameter to handshake_state_install_igtk into one
parameter for the actual IGTK buffer and one for the IPN buffer instead
of requiring the caller to have them both in one continuous buffer.
With FT protocol, one is received encrypted and the other in plain text.
Make sure that the Neighbor Report timeout is cancelled when connection
breaks or device is being destroyed, and call the callback. Add an
errno parameter to the callback to indicate the cause.
With this patch an actual fast transition should happen when the signal
strength goes low but there are still various details to be fixed before
this becomes useful:
* the kernel tends to return cached scan results and won't update the
rssi values,
* there's no timer to prevent too frequent transition attempts or to
retry after some time if the signal is still low,
* no candidate other than the top ranked BSS is tried. With FT it
may be impossible to try another BSS anyway although there isn't
anything in the spec to imply this. It would require keeping the
handshake_state around after netdev gives up on the transition
attempt.
Trigger a scan of the selected channels or all channels if no useful
neighbor list was obtained, then process the scan results to select the
final target BSS.
The actual transition to the new BSS is not included in this patch for
readability.
Trigger a roam attempt when the RSSI level has been low for at least 5
seconds using the netdev RSSI LOW/HIGH events. See if neighbor reports
are supported and if so, request and process the neighbor reports list
to restrict the number of channels to be scanned. The scanning part is
not included in this patch for readability.
Validate the fourth message of the fast transition sequence and save the
new keys and state as current values in the netdev object. The
FT-specific IE validation that was already present in the initial MD
is moved to a new function.
Build and send the FT Authentication Request frame, the initial Fast
Transition message.
In this version the assumption is that once we start a transition attempt
there's no going back so the old handshake_state, scan_bss, etc. can be
replaced by the new objects immediately and there's no point at which both
the old and the new connection states are needed. Also the disconnect
event for the old connection is implicit. At netdev level the state
during a transition is almost the same with a new connection setup.
The first disconnect event on the netlink socket after the FT Authenticate
is assumed to be the one generated by the kernel for the old connection.
The disconnect event doesn't contain the AP bssid (unlike the
deauthenticate event preceding it), otherwise we could check to see if
the bssid is the one we are interested in or could check connect_cmd_id
assuming a disconnect doesn't happen before the connect command finishes.
This adds support for iwd.conf 'ManagementFrameProtection' setting.
This setting has the following semantics, with '1' being the default:
0 - MFP off, even if hardware is capable
1 - Use MFP if available
2 - MFP required. If the hardware is not capable, no connections will
be possible. Use at your own risk.
Despite RFC3748 mandating MSKs to be at least 256 bits some EAP methods
return shorter MSKs. Since we call handshake_failed when the MSK is too
short, EAP methods have to be careful with their calls to set_key_material
because it may result in a call to the method's .remove method.
EAP-TLS and EAP-TTLS can't handle that currently and would be difficult to
adapt because of the TLS internals but they always set msk_len to 64 so
handshake_failed will not be called.
Make sure that eap_set_key_material can free the whole EAP method and
EAP state machine before returning, by calling that function last. This
relies on eap_mschapv2_handle_success being the last call in about 5
stack frames above it too.
Action Frames are sent by nl80211 as unicast data. We're not receiving
any other unicast packets in iwd at this time so let netdev directly
handle all unicast data on the genl socket.
Add a version of scan_active that accepts a struct with the scan
parameters so we can more easily add new parameters. Since the genl
message is now built within scan_active_start the extra_ie memory
can be freed by the caller at any time.
clang complains about enum as var_arg type
because of the argument standard conversion.
In a small test I did neither clang nor gcc can
properly warn about out of range values, so it's
purely for documentation either way.
There are situations when a CMD_DISCONNECT or deauthenticate will be
issued locally because of an error detected locally where netdev would
not be able to emit a event to the device object. The CMD_DISCONNECT
handler can only send an event if the disconnect is triggered by the AP
because we don't have an enum value defined for other diconnects. We
have these values defined for the connect callback but those errors may
happen when the connect callback is already NULL because a connection
has been estabilshed. So add an event type for local errors.
These situations may occur in a transition negotiation or in an eapol
handshake failure during rekeying resulting in a call to
netdev_handshake_failed.
The kernel parses NL80211_ATTR_USE_MFP to mean an enumeration
nl80211_mfp. So instead of using a boolean, we should be using the
value NL80211_MFP_REQUIRED.
Make the use of EAPOL-Start the default and send it when configured for
8021x and either we receive no EAPOL-EAP from from the AP before
timeout, or if the AP tries to start a 4-Way Handshake.
On certain routers, the 4-Way handshake message 3 of 4 contains a key iv
field which is not zero as it is supposed to. This causes us to fail
the handshake.
Since the iv field is not utilized in this particular case, it is safe
to simply warn rather than fail the handshake outright.
Use the NLMSG_ALIGN macro on the family header size (struct ifinfomsg in
this case). The ascii graphics in include/net/netlink.h show that both
the netlink header and the family header should be padded. The netlink
header (nlmsghdr) is already padded in ell. To "document" this
requirementin ell what we could do is take two buffers, one for the
family header and one for the attributes.
This doesn't change anything for most people because ifinfomsg is
already 16-byte long on the usual architectures.
Remove the keys and other data from struct eapol_sm, update device.c,
netdev.c and wsc.c to use the handshake_state object instead of
eapol_sm. This also gets rid of eapol_cancel and the ifindex parameter
in some of the eapol functions where sm->handshake->ifindex can be
used instead.
