hostapd needs to remove the old STA entry if it exists when processing
reassociation back to the same AP. This removes the potentially PS
buffered frames and allows association parameters to be updated with
mac80211.
Store a copy of device attributes during WPS protocol run and make it
available for external programs via the control interface STA MIB
command for associated stations. This gives access to device name and
type which can be useful when showing user information about associated
stations.
The group key state machine needs to be re-initialized with possible
updated GTK length when restarting WPA (e.g., when WPS was used to
reconfigure the AP).
This is not really of that much use since rc4_skip() can be used as
easily. In addition, rc4 has caused some symbol conflicts in the past,
so it is easier to live without that as an exported symbol.
This is a (hopefully) temporary workaround to allow the same source code
tree to be used for building hostapd and wpa_supplicant without having
to manually force recompilation of some files. Currently, some of the
driver wrapper files need to be built separately for hostapd and
wpa_supplicant (#ifdef's in the files based on AP functionality).
This is somewhat racy as far as parallel make execution is concerned,
i.e., it may be necessary to run "make -j#" twice (plain "make" works
fine. Since this is supposed to be a temporary workaround, there is not
much point in trying to fix this with any more complex make processing.
Instead of having all driver stuff collected across wpa_supplicant
and hostapd, create a common snippet that they both include and
that handles the build configuration.
Instead of calling specific Probe Request handler functions, use a
generic mechanism that allows multiple callback functions to be
registered for getting notification on receive Probe Request frames.
The driver wrappers should not need to include wps_hostapd.h, so let's
make this easier by introducing a driver callback for reporting Probe
Request frames.
Previously, we would have allowed both the WPA and RSN EAPOL-Key
types to be used regardless of whether the association is using
WPA or RSN/WPA2. This shouldn't result in any significant problems
on the Authenticator side, but anyway, we should check the type and
ignore the EAPOL-Key frames that used unexpected type.
hostapd_cli wps_pin command can now have an optional timeout
parameter that sets the PIN lifetime in seconds. This can be used
to reduce the likelihood of someone else using the PIN should an
active PIN be left in the Registrar.
We could use auto-channel selection here eventually, but for now,
reject the configuration since it is not going to work correctly
(Beacon and Probe Response frames use incorrect value in DS Params).
Port the code from wpa_supplicant to re-use an existing ctrl_iface
socket file if the file does not seem to be in use. This allows
hostapd to recover from unclean shutdown of the control interface.
None of the driver wrappers user this. hostapd-controlled broadcast SSID
hiding can only be used with drivers that use hostapd for handling
Beacon and Probe Request/Response frames.
None of the driver wrappers use this. Only the drivers that use hostapd
for Beacon and Probe Request/Response handling can now use IEEE 802.11d
properly.
This was not really supported by any of the included driver wrappers. If
this functionality is desired in the future, this (or something similar)
can be added with the changes needed into a driver wrapper to use the
mechanism.
This simplifies driver wrapper operations and removes last direct
struct hostapd_data dereferences from driver_nl80211.c. In addition,
some of the TX callbacks are now fixed for secondary BSSes.
This fixes deauth/disassoc frames in secondary BSSes when using
multi-BSSID. In addition, it reduces need to dereference
struct hostapd_data inside driver wrappers.
Instead of adding a new driver_ops for fetching neighbor BSS data (that
nl80211 driver interface had to scan during initialization), share the
same scan operations that wpa_supplicant is using. This gets rid of
duplicated scan code in driver_nl80211.c (and better yet, removes large
part of old WEXT code).
hostapd interface initialization is now completed in a callback, if
needed, i.e., he_features channel/hw_mode selection can use as much time
as needed. This can also help with radar detection in the future.
Use a parameter structure to pass in information that can be more easily
extended in the future. Include some of the parameters that were
previously read directly from hapd->conf in order to reduce need for
including hostapd/config.h into driver wrappers.
This was not documented properly and was not really used nor would it be
suitable to be used in generic way as it was implemented. It is better
to just remove the parameter since there does not seem to be any
reasonable use for it.
This merges the driver wrapper implementations to use the same
implementation both for hostapd and wpa_supplicant operations to avoid
code duplication.
This commit merges the driver_ops structures and implementations from
hostapd/driver*.[ch] into src/drivers. This is only an initial step and
there is room for number of cleanups to share code between the hostapd
and wpa_supplicant parts of the wrappers to avoid unnecessary source
code duplication.
This fixes multi-BSS configuration with driver_nl80211.c to mark STAs
that use secondary BSSes with open/static WEP without having to make
driver_nl80211.c track 802.1X configuration for each BSS.
Static WEP keys were configured only for the first BSS. In addition,
STAs were flushed only for the first BSS. These operations should be in
hostapd_setup_bss(), not setup_interface().
Remove extra call to ieee802_11_set_beacon() for the first BSS. This
should only be done from hostapd_setup_bss(), i.e., once for each BSS.
No need for a separate driver_ops handler for setting DTIM period since
this is always set at the same time with the Beacon data. Beacon
interval is still set separately since it is consider per-radio
parameter (Beacon data and DTIM period are per-BSS parameters).
IEEE 802.11r KDF uses key length in the derivation and as such, the PTK
length must be specified correctly. The previous version was deriving
using 512-bit PTK regardless of the negotiated cipher suite; this works
for TKIP, but not for CCMP. Update the code to use proper PTK length
based on the pairwise cipher.
This fixed PTK derivation for both IEEE 802.11r and IEEE 802.11w (when
using AKMP that specifies SHA-256-based key derivation). The fixed
version does not interoperate with the previous versions. [Bug 307]
Move the shared IEEE 802.11w enum definition into src/common/defs.h to
avoid redefinition when both configuration structures are included into
the same file.
The actual pointer to struct sta_info was not really used and it is
enough to use a single bit to indicate whether an AID is allocated. This
makes the BSS data take less memory while making the allocation routine
faster and removing the arbitrary MAX_AID_TABLE_SIZE limit of 128 STAs.
Remove all fields before sun_path before printing or comparing sun_path
contents. Using offsetof should be portable. In addition, set sun_len
for FreeBSD.
This was broken by 510c02d4a3 which added
validation of eap_ttls_phase2_eap_init() return value. The main problem
in the code trying to initialize a new phase 2 EAP method
unconditionally; this should only happen if there is a new method in the
inner method sequence.
If every secondary BSS is configured with a pre-set BSSID, hostapd does
not enforce the BSSID mask requirements anymore, i.e., they are used
only if hostapd is responsible for generating MAC addresses for virtual
interfaces.
This is needed to make mac80211 work with multi-BSS configuration. The
previous design ended up setting DTIM period for secondary BSSes before
setting the Beacon and driver_nl80211.c was not really prepared for
that. Eventually, the Beacon configuration routines should be combined
into a single driver operation, but for now, just moving this call is
the simplest workaround.
hostapd will now go through the RIC Request and process each RDIE. Only
WMM TSPEC requests are currently supported; all other request
descriptors will be declined.
RIC Response is written by hostapd and verified by wpa_supplicant (MIC
validation). wpa_supplicant does not yet have code to notify the driver
about the resource request results.
This adds first part of FT resource request as part of Reassocition
Request frame (i.e., FT Protocol, not FT Resource Request Protocol).
wpa_supplicant can generate a test resource request when driver_test.c
is used with internal MLME code and hostapd can verify the FTIE MIC
properly with the included RIC Request.
The actual RIC Request IEs are not processed yet and hostapd does not
yet reply with RIC Response (nor would wpa_supplicant be able to
validate the FTIE MIC for a frame with RIC Response).
Windows XP and Vista clients can get confused about EAP-Identity/Request
when they probe the network with EAPOL-Start. In such a case, they may
assume the network is using IEEE 802.1X and prompt user for a
certificate while the correct (non-WPS) behavior would be to ask for the
static WEP key. As a workaround, use Microsoft Provisioning IE to
advertise that legacy 802.1X is not supported.
This seems to make Windows ask for a static WEP key when adding a new
network, but at least Windows XP SP3 was still marking IEEE 802.1X
enabled for the network. Anyway, this is better than just leaving the
network configured with IEEE 802.1X and automatic WEP key distribution.
Calculate the estimated medium time using integer variables since there
is no real need to use floating point arithmetics here. In addition,
make sure there is no division by zero regardless of how invalid the
request from the station is. Reject invalid parameters and refuse
requests that would take most of the bandwidth by themselves.
Add test code into wpa_supplicant mlme.c to allow WMM-AC negotiation to
be tested with driver_test.
The new file wps_nfc.c and ndef.c implements NFC device independent
operation, wps_nfc_pn531.c implements NFC device dependent operation.
This patch is only for the following use case:
- Enrollee = wpa_supplicant
- Registrar = hostapd internal Registrar
Following NFC methods can be used:
- Enrollee PIN with NFC
- Registrar PIN with NFC
- unencrypted credential with NFC
Encrypted credentials are not supported.
Enrollee side operation:
Registrar side operation:
Example configuration.
CONFIG_WPS=y
CONFIG_WPS_NFC=y
CONFIG_WPS_NFC_PN531=y
I used NFC device "NXP PN531". The NFC device access method is
confidential, so I used outer library. Please download below files from
https://www.saice-wpsnfc.bz/index.php
[WPS NFC Library]
WpsNfcLibrary/WpsNfc.h
WpsNfcLibrary/WpsNfcType.h
WpsNfcLibrary/WpsNfcVersion.h
WpsNfcLibrary/linux/libnfc_mapping_pn53x.dll
WpsNfcLibrary/linux/wpsnfc.dll
[NFC Reader/Writer Kernel Driver]
NFCKernelDriver-1.0.3/linux/kobj/sonyrw.ko
<WiFi test>
The hostapd/wpa_supplicant with this patch passed below tests on
"Wi-Fi WPS Test Plan Version 1.6".
4.2.5 Add device using NFC Method with password token
(I used SONY STA instead of NXP STA.)
4.2.6 Add device using NFC Method with configuration token
5.1.9 Add to AP using NFC Method with password token
through internal registrar
(I used SONY AP instead of NXP AP.)
5.1.10 Add to AP using NFC Method with configuration token
through internal registrar
This updates the terminogy to match with the final WMM specification. In
addition, some of the WMM TSPEC structure fields were in incorrect order
and used without byte order swapping. Those are also taken care of this
cleanup patch.
This patch replaces the station's ht capability information with the
negotiated one in NL80211_CMD_NEW_STATION. This negotiated ht
capability will be needed for rate control initialization in the
driver.
Signed-off-by: vasanth <vasanth@atheros.com>
The EAP server state machine will need to have special code in
getDecision() to avoid starting passthrough operations before having
completed Identity round in the beginning of reauthentication. This was
broken when moving into using the full authenticator state machine from
RFC 4137 in 0.6.x.
The old behavior of generating new DH keys can be maintained for non-OOB
cases and only OOB (in this case, with UFD) will use the pre-configured
DH keys to allow the public key hash to be checked.
Not all embedded devices have USB interface and it is useful to be able
to remove unneeded functionality from the binary. In addition, the
current implementation has some UNIX specific calls in it which may make
it not compile cleanly on all target systems.
Need to set WLAN_STA_WPS and WLAN_STA_MAYBE_WPS flags even if WPA is not
enabled. This allows open and static WEP modes to initiate WPS
negotiation with madwifi-like drivers.
This uses similar, but not identical, interface to madwifi. It is easier
to keep this separate to avoid conflicts with potential changes in the
driver interfaces.
TX/RX bytes are now reported correctly (typo ended up leaving TX bytes
uninitialized and set RX bytes value to use correct TX bytes). TX/RX
packet counts are not yet available from kernel, so we have to clear the
values to avoid reporting bogus data.
On WPS init/deinit process, the hostapd clears it's own WPS IE
with 0 length WPS IE. But it fails. Because the parameter to
ioctl is too short. Then hostapd prints a below message.
ioctl[IEEE80211_IOCTL_SET_APPIEBUF]: Invalid argument
Allow more than one pending PutWLANMessage data to be stored (M2/M2D
from multiple external Registrars) and drop pending M2/M2D messages when
the Enrollee replies with M3.
It looks like Intel wsccmd may send a bogus NewWLANEventMAC
(11:22:33:44:55:66) when acting as an wired external Registrar. Work
around this by going through all STAs if the address does not match and
pick the STA that is in an ongoing WPS registration.
If you don't choose OpenSSL as TLS implementation and choose to enable
CONFIG_EAP_TNC you have to link against libdl. The OpenSSL libraries
implicitly link against them, so this might be a reason why it wasn't
noticed yet. I assume the same applies to hostapd.
We can now handle up to 65535 byte result buffer which is the maximum
due to WEXT using 16-bit length field. Previously, this was limited to
32768 bytes in practice even through we tried with 65536 and 131072
buffers which we just truncated into 0 in the 16-bit variable.
This more or less doubles the number of BSSes we can received from scan
results.
MadWifi is unlikely to be in ../head relative to hostapd or
wpa_supplicant, as it would be inside the hostap git repository.
MadWifi sources are more likely to be in a directory called "madwifi"
and residing outside the hostap repository. Using "madwifi" also
demonstrates that the top-level madwifi directory is needed.
Try to match PRI/SEC channel with neighboring 20/40 MHz BSSes per
IEEE 802.11n/D7.0 11.14.3.2. This is not yet complete implementation,
but at least some parts of the 40 MHz coex are improved.
40 MHz operation maybe rejected (i.e., fall back to using 20 MHz) or
pri/sec channels may be switched if needed.
I think that the "radius" pointer in the structure hostapd_config is
never used; when the configuration is parsed the related data is stored
in hostapd_bss_config's "radius" var.
This adds mostly feature complete external Registrar support with the
main missing part being proper support for multiple external Registrars
working at the same time and processing of concurrent registrations when
using an external Registrar.
This code is based on Sony/Saice implementation
(https://www.saice-wpsnfc.bz/) and the changes made by Ted Merrill
(Atheros) to make it more suitable for hostapd design and embedded
systems. Some of the UPnP code is based on Intel's libupnp. Copyrights
and licensing are explained in src/wps/wps_upnp.c in more detail.
The inactivity poll was originally supposed to use Data::Nullfunc, but
due to Prism2/2.5/3 firmware issues, this was changed to an empty
Data::Data frame. mac80211 does not have such an issue, so change the
inactivity poll frame to be Data::Nullfunc by default and use the
Data::Data workaround only with Host AP driver.
Previous version was discarding TX status for FromDS data frames, but
those are the exact ones that we need to check for inactivity poll to
work, i.e., they are TX status reports for injected data frames.
In addition, remove the debug printing of TX status for data frame since
that could fill up the debug output if kernel-side filtering cannot be
used with monitor interface.
TX status information for all transmitted data frames is not going to
be sent to hostapd anymore, so the CPU load with high traffic load is
going to be significantly reduced.
If a Registrar tries to configure the AP, but fails to validate the
device password (AP PIN), lock the AP setup after four failures. This
protects the AP PIN against brute force guessing attacks.
This optional configuration parameter can be used to override AP
Settings attributes in M7 similarly to extra_cred option for Credential
attribute(s) in M8.
Do not initialize EAPOL state machine for the STA when hostapd is
configured to use WPS with open or shared WEP networks. This allows the
STA to use EAPOL-Start to indicate it wants to start WPS in such a case
and hostapd does not end up running through EAPOL authentication timeout
and disconnecting the STA if WPS is not used.
There was already code for starting EAPOL state machines based on
received EAPOL packets, but that was not working properly since
portEnabled was not set to TRUE on that code path. This is now fixed,
too.
This operation can now be moved into an external program by configuring
hostapd with wps_cred_processing=1 and skip_cred_build=1. A new
ctrl_iface message (WPS-REG-SUCCESS <Enrollee MAC addr> <UUID-E>) will
be used to notify external programs of each successful registration and
that can be used as a tricker to move from unconfigured to configured
state.
This behaves like the one in wpa_supplicant, i.e., hostapd can be
configured not to process new credentials (AP settings) internally and
instead pass the WPS attributes for an external program to process over
ctrl_iface.
The default interval is now 5 seconds (used to be 1 second for
interactive mode and 2 seconds for wpa_cli -a). The interval can be
changed with -G<seconds> command line option.
The separate Association Comeback Time IE was removed from IEEE 802.11w
and the Timeout Interval IE (from IEEE 802.11r) is used instead. The
editing on this is still somewhat incomplete in IEEE 802.11w/D7.0, but
still, the use of Timeout Interval IE is the expected mechanism.
This makes it easier to pass the credential data to external programs
(e.g., Network Manager) for processing. The actual use of this data is
not yet included in hostapd/wpa_supplicant.
This cleans up the driver wrapper interface by getting rid of sta_info.h
dependency in all drivers that use MLME implementation in hostapd
(driver_hostap.c and driver_nl80211.c).
driver.h contains the definitions needed in driver wrapper
implementations (driver_*.c) and driver_i.h contains the definitions
that are used in core hostapd code to interact with the driver wrappers.
The configuration parsing functions seemed to have worked fine before,
but these were real bugs even if they did not show up in practice.
hostapd_ip_diff() was broken for IPv6 addresses (overwrote address and
always returned 1.
This updated all doxygen runs to use the same style that was used for
wpa_supplicant full documents. The full vs. fast configurations are now
otherwise identical apart from fast not generating dot files or
latex/pdf version of the documentation.
Generate a SHA1 hash -based UUID from the local MAC address if the UUID
was not configured. This makes it easier to prepare for WPS since there
is no need to generate an UUID.
mac80211 can now figure out which key to use for injected frames (in
most cases), so we can remove the workaround for configuring IGTK on the
monitor interface that is used for injecting frames.
There is not really much else the Authenticator can do if it does not
receive valid EAP response from the Supplicant/EAP peer. EAP-Failure
would need to be sent before trying to start again with
EAP-Request/Identity, but that is not allowed before the EAP peer
actually replies. Anyway, forcing a new association is likely to clean
up peer state, too, so it can help fixing some issues that could have
caused the peer not to be able to reply in the first place.
It looks like this never survived the move from IEEE 802.1X-2001 to
IEEE 802.1X-2004 and EAP state machine (RFC 4137). The retransmission
scheduling and control is now in EAP authenticator and the
calculateTimeout() producedure is used to determine timeout for
retransmission (either dynamic backoff or value from EAP method hint).
The recommended calculations based on SRTT and RTTVAR (RFC 2988) are not
yet implemented since there is no round-trip time measurement available
yet.
This should make EAP authentication much more robust in environments
where initial packets are lost for any reason. If the EAP method does
not provide a hint on timeout, default schedule of 3, 6, 12, 20, 20, 20,
... seconds will be used.
Previously, only the delivery option 1 from RFC 4284
(EAP-Request/Identity from the AP) was supported. Now option 3
(subsequent EAP-Request/Identity from RADIUS server) can also be used
when hostapd is used as a RADIUS server. The eap_user file will need to
have a Phase 1 user entry pointing to Identity method in order for this
to happen (e.g., "* Identity" in the end of the file). The identity hint
is configured in the same was as for AP/Authenticator case (eap_message
in hostapd.conf).
This commit changes just the name and Action category per D7.0. The
retransmit/timeout processing in the AP is not yet updated with the
changes in D7.0.
dot11RSNAConfigGroupUpdateTimeOut and
dot11RSNAConfigPairwiseUpdateTimeOut MIB variables were only used in
draft versions of IEEE 802.11i, so rename these in order not to use
confusing name here.
Replaced EAPOL-Key timeout to use following timeouts (in
milliseconds): 100,1000,1000,1000 (this was 1000,1000,1000,0). There
is no point in sending out the final EAPOL-Key frame which would be
immediately followed by disconnection. After the change to allow
response to any pending EAPOL-Key frame, it is fine to send the first
retransmission quickly to avoid long wait in cases where Supplicant
did not receive the first frame for any reason. The new sequence will
still provide 3.1 seconds of time to get any response frame, so this
does not reduce the previous time.
Accept response to any pending request, not just the last one. This
gives the Supplicant more time to reply since hostapd will now allow up
to three seconds for the reply to the first EAPOL-Key frame transmission
(and two seconds for the first retry and one second for the last) while
the previous version invalidated any old request immediately when
sending a retransmitted frame.
If the Supplicant replies to more than one request, only the first reply
to arrive at the Authenticator will be processed. As far as the
Supplicant is concerned, this behavior does not differ from the previous
one except for being less likely to cause unneeded retransmissions of
EAPOL-Key frames.
This can help in cases where power saving is used when the group key is
rekeyed or when there is excessive traffic on the channel that can delay
(or drop) EAPOL-Key frames.
driver_test can now be used either over UNIX domain socket or UDP
socket. This makes it possible to run the test over network and makes it
easier to port driver_test to Windows.
hostapd configuration: test_socket=UDP:<listen port>
wpa_supplicant configuration: driver_param=test_udp=<dst IP addr>:<port>
Unfortunately, at least the current libnl git snapshot changes the API
in backwards incompatible way and in a way that makes it difficult to
to allow building against the latest libnl code.
This is currently happening way too frequently (mac80211 monitor
interface sends TX info for every frame) and the end result makes it
difficult to read hostapd debug log if there is large amount of data
traffic.
Only one of the authentication frame types is encrypted. In order for
static WEP encryption to work properly (i.e., to not encrypt the frame),
we need to tell mac80211 about the frames that must not be encrypted.
If the phy info from nl80211 does not include 802.11b mode, generate
that mode based on 802.11g information. This allows hw_mode=b to be used
with drivers that support 2.4 GHz band.
This is just making an as-is copy of EAP-AKA server and peer
implementation into a new file and by using the different EAP method
type that is allocated for EAP-AKA' (50). None of the other differences
between EAP-AKA and EAP-AKA' are not yet included.
It is likely that once EAP-AKA' implementation is done and is found to
work correctly, large part of the EAP-AKA and EAP-AKA' code will be
shared. However, it is not reasonable to destabilize EAP-AKA
implementation at this point before it is clearer what the final
differences will be.
Since the Registrar may not yet know the UUID-E when a new PIN is
entered, use of a wildcard PIN that works with any UUID-E can be useful.
Such a PIN will be bound to the first Enrollee trying to use it and it
will be invalidated after the first use.
If a STA reassociates and changes key_mgmt (e.g., from WPA-PSK to WPS),
hostapd needs to reset some of the existing STA and WPA state machine
variables to allow correct processing for the new association.
WPS IE is now passed from hostapd association processing into EAP-WSC
and WPS processing. Request Type attribute is parsed from this
information and if the request is for a WLAN Manager Registrar,
additional management keys are derived (to be used with UPnP).
This depends on a patch to Linux nl80211/mac80211 that has not yet been
merged into wireless-testing. If that change is not present, the old
mechanism (WEXT) will be used instead.
It is better to pass both HT Capabilities and HT Operation IEs in the
same function call since it may be easier for the driver wrappers to
handle the changes without having to wait for the other IE in the
wrapper code.
If country_code is set in hostapd.conf, hostapd will now update nl80211
regulatory data by setting the alpha2 string for CRDA. In other words,
"iw reg set <alpha2>" is not needed anymore when using hostapd.
This adds WPS support for both hostapd and wpa_supplicant. Both programs
can be configured to act as WPS Enrollee and Registrar. Both PBC and PIN
methods are supported.
Currently, hostapd has more complete configuration option for WPS
parameters and wpa_supplicant configuration style will likely change in
the future. External Registrars are not yet supported in hostapd or
wpa_supplicant. While wpa_supplicant has initial support for acting as
an Registrar to configure an AP, this is still using number of hardcoded
parameters which will need to be made configurable for proper operation.
Changed accounting_sta_start() to call accounting_sta_get_id()
internally in accounting.c so that external callers do not need to do
anything to allocate unique accounting id. When starting a new session,
a unique identifier is needed anyway, so no need to keep these
operations separate.
This was used to allow hostapd to associate as a non-AP STA to another
AP one the same channel while still acting as an AP with the Host AP
driver. This was very experimental and did not work with all firmware
versions. Nowadays, much better way of doing this is to use mac80211
virtual non-AP STA interface. As such, this experimental code can be
removed from hostapd to reduce the code size and make MLME code easier
to understand since it is now only handling AP functionality.
This code was originally added as a mechanism to handle long waits
during channel selection and/or radar detection. It is not currently
really used and makes the setup sequence nearly impossible to
understand. Let's get rid of the unwanted complexity. This needs to be
redesigned if it is ever needed again.
This code was not finished and did not work with the current mac80211
design. In order to avoid confusing users, it is better to remove this
completely for now and look at new implementation to work with mac80211.
It the message was large enough to require fragmentation (e.g., if a large
Session Ticket data is included), More Fragment flag was set, but no
more fragments were actually sent (i.e., Access-Accept was sent out).
These typedefs were causing build issues with new kernel/C library headers,
so lets get rid of them since they do not seem to be needed anymore. This
applies only if CONFIG_FULL_DYNAMIC_VLAN is enabled which is not even
mentioned in the defconfig file, so this should not change behavior more
most users.
If the driver wrapper does not implement passive_scan handler, do not try
to use strerror() to figure out what the error meant. This is not really an
error that the user should be notified about.
