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.
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.
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.
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]'
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.
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.
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.
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)
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.
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.
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.
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 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.
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.
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.
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.
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.
==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)
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)
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.
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.
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.
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.
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.
In many cases the pairwise and group cipher information is not the only
information needed from the BSS RSN/WPA elements in order to make a
decision. For example, th MFPC/MFPR bits might be needed, or
pre-authentication capability bits, group management ciphers, etc.
This patch refactors bss_get_supported_ciphers into the more general
scan_bss_get_rsn_info function
Fix autoconnect trying to connect to networks never used before as found
by Tim Kourt. Update the comments to be consistent with the use of the
is_known field and the docs, in that a Known Network is any network that
has a config file in the iwd storage, and an autoconnect candidate is a
network that has been connected to before.
Use the org.freedesktop.DBus.Properties interfaces on objects with
properties and drop the old style GetProperty/SetProperty methods on
individual interfaces. Agent and KnownNetworks have no properties at
this time so don't add org.freedesktop.DBus.Properties interfaces.
This also fixes a potential buffer overflow since the ssid was cast to a
string inside network_create. However, ssid is a buffer of 32 bytes,
and would not be null-terminated in the case of a 32-byte SSID.
Note that the autoconnect_list may still contain the network. Currently
only the top entry from the list is ever used and only on
new_scan_results(), i.e. at the same time the list is being created.
If at some point it becomes part of actual device state it needs to also
be reset when a network is being forgotten.
network_info gets a is_known flag that is used for the
GetOrderedNetworks tracking and to implement the KnownNetworks
interface - loading of the list of known networks on startup and
forgetting networks.
For simplicity and future use (possibly performance), every struct network
gets a pointer to a network_info structure, there's one network_info for
every network being by any interface, not only known networks. The SSID
and security type information is removed from struct network because the
network_info holds that information.
network_info also gets a seen_count field to count how many references
from network.info fields it has, so as to fix the removal of
network_info structures. Previously, once they were added to the
networks list, they'd stay there forever possibly skewing the network
ranking results.
This also fixed the network ranking used by GetOrderedNetwork which
wasn't working due to a missing assignment of *index in
network_find_info also triggering valgrind alerts.
A function that calculates a new rank type to order all networks
currently seen by a netdev. The order is designed for displaying the
list to user so that the networks most likely to be wanted by the user
are first on the list.
Since the rankmod value only makes sense for autoconnectable networks,
change network_rankmod to return an indication of whether the rankmod is
valid as a boolean instead of as a double, as discussed before.
Make sure networks of all 4 security types have a settings file created
or updated with a new modification time on a successful connect so that
autoconnect and network sorting works for networks other than PSK too.
By doing this on storage_network_touch failure we make sure we don't
overwrite anything dropped into the settings directory while we were
connecting.
for network_seen and network_connected
Only accept a struct network pointer instead of separately the ssid and
security type. This is needed so we can do some more simplification in
the next patch by having access to the network struct.
It looks like with multiple netdev seeing the same networks we'd create
multiple network_info structures for each network. Since the
"networks" list (of network_info structs) is global that's probbaly not
the intention here.
