Add a 16-bit token index into the anti-clogging token. This can be used
to enforce only a single use of each issued anti-clogging token request.
The token value is now token-index |
last-30-octets-of(HMAC-SHA256(sae_token_key, STA-MAC-address |
token-index)), i.e., the first two octets of the SHA256 hash value are
replaced with the token-index and token-index itself is protected as
part of the HMAC context data.
Track the used 16-bit token index values and accept received tokens only
if they use an index value that has been requested, but has not yet been
used. This makes it a bit more difficult for an attacker to perform DoS
attacks against the heavy CPU operations needed for processing SAE
commit since the attacker cannot simply replay the same frame multiple
times and instead, needs to request each token separately.
While this does not add significant extra processing/CPU need for the
attacker, this can be helpful in combination with the queued processing
of SAE commit messages in enforcing more delay during flooding of SAE
commit messages since the new anti-clogging token values are not
returned before the new message goes through the processing queue.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
This allows better control of processing new SAE sessions so that other
operations can be given higher priority during bursts of SAE requests,
e.g., during a potential DoS attack. The receive commit messages are
queued (up to maximum of 15 entries) and processed from eloop callback.
If the queue has multiple pending entries, more wait time is used to go
through the each new entry to reduce heavy CPU load from SAE processing.
Enable anti-clogging token use also based on the pending commit message
queue and not only based on the already started sessions.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Change the AP mode default for SAE to enable only the group 19 instead
of enabling all ECC groups that are supported by the used crypto library
and the SAE implementations. The main reason for this is to avoid
enabling groups that are not as strong as the mandatory-to-support group
19 (i.e., groups 25 and 26). In addition, this disables heavier groups
by default.
In addition, add a warning about MODP groups 1, 2, 5, 22, 23, and 24
based on "MUST NOT" or "SHOULD NOT" categorization in RFC 8247. All the
MODP groups were already disabled by default and would have needed
explicit configuration to be allowed.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
This extension of VLAN assignment code had a bug in one of the code
paths where vlan_id could have been left uninitialized. This could
result in SAE authentication getting rejected in cases where VLAN
assignment is not used if the uninitialized stack memory had nonzero
value.
Fixes: dbfa691df4 ("VLAN assignment based on used WPA/WPA2 passphrase/PSK")
Signed-off-by: Jouni Malinen <j@w1.fi>
Avoid an unnecessary unsigned integer overflow warning due to loop index
j-- use.
hostapd.c:661:10: runtime error: unsigned integer overflow: 0 - 1 cannot be represented in type 'unsigned int'
Signed-off-by: Jouni Malinen <j@w1.fi>
(&mgmt->u.deauth.reason_code + 1) is not exactly clean and now that we
have the u8 variable[] member in the struct after this field, use that
directly to avoid clang compiler warning:
ctrl_iface_ap.c:454:18: error: taking address of packed member
'reason_code' of class or structure 'ieee80211_mgmt::(anonymous
union)::(anonymous)' may result in an unaligned pointer value
[-Werror,-Waddress-of-packed-member]
Signed-off-by: Jouni Malinen <j@w1.fi>
Split the check and decrementation into separate steps to avoid an
unnecessary UBSan warning.
hostapd.c:1895:14: runtime error: unsigned integer overflow: 0 - 1 cannot be represented in type 'size_t' (aka 'unsigned long')
Signed-off-by: Jouni Malinen <j@w1.fi>
hapd->conf might be NULL in case initialized failed, so better be
prepared for that when debug printing interface name in the deinit path.
hostapd.c:312:54: runtime error: member access within null pointer of type 'struct hostapd_bss_config'
hostapd.c:351:29: runtime error: member access within null pointer of type 'struct hostapd_bss_config'
hostapd.c:2158:18: runtime error: member access within null pointer of type 'struct hostapd_bss_config'
Signed-off-by: Jouni Malinen <j@w1.fi>
iface->num_bss is unsigned integer, so need to explicit typecast it to
unsigned before decrementation by one even when the result is stored in
an unsigned integer.
../src/ap/hostapd.c:2185:26: runtime error: unsigned integer overflow: 0 - 1 cannot be represented in type 'unsigned long'
Signed-off-by: Jouni Malinen <j@w1.fi>
According to IEEE Std 802.11-2016, 9.4.2.25 when fields of an RSNE are
not included, the default values are used. The cipher suite defaults
were hardcoded to CCMP in the previous implementation, but the default
is actually different for DMG: GCMP (per 9.4.2.25.2).
It is not possible to find out from the RSNE if the network is non-DMG
or DMG, so callers of wpa_parse_wpa_ie_rsn() need to handle this case
based on context, which can be different for each caller.
In order to fix this issue, add flags to the wpa_ie_data indicating
whether pairwise/group ciphers were included in the RSNE. Callers can
check these flags and fill in the appropriate ciphers. The
wpa_parse_wpa_ie_rsn() function still initializes the ciphers to CCMP by
default so existing callers will not break. This change also fixes some
callers which need to handle the DMG network case.
Signed-off-by: Lior David <liord@codeaurora.org>
The Wi-Fi Alliance Multi-AP Specification v1.0 allows onboarding of a
backhaul STA through WPS. To enable this, the WPS Registrar offers a
different set of credentials (backhaul credentials instead of fronthaul
credentials) when the Multi-AP subelement is present in the WFA vendor
extension element of the WSC M1 message.
Add new configuration options to specify the backhaul credentials for
the hostapd internal registrar: multi_ap_backhaul_ssid,
multi_ap_backhaul_wpa_psk, multi_ap_backhaul_wpa_passphrase. These are
only relevant for a fronthaul SSID, i.e., where multi_ap is set to 2 or
3. When these options are set, pass the backhaul credentials instead of
the normal credentials when the Multi-AP subelement is present.
Ignore the Multi-AP subelement if the backhaul config options are not
set. Note that for an SSID which is fronthaul and backhaul at the same
time (i.e., multi_ap == 3), this results in the correct credentials
being sent anyway.
The security to be used for the backaul BSS is fixed to WPA2PSK. The
Multi-AP Specification only allows Open and WPA2PSK networks to be
configured. Although not stated explicitly, the backhaul link is
intended to be always encrypted, hence WPA2PSK.
To build the credentials, the credential-building code is essentially
copied and simplified. Indeed, the backhaul credentials are always
WPA2PSK and never use per-device PSK. All the options set for the
fronthaul BSS WPS are simply ignored.
Signed-off-by: Davina Lu <ylu@quantenna.com>
Signed-off-by: Igor Mitsyanko <igor.mitsyanko.os@quantenna.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Cc: Marianna Carrera <marianna.carrera.so@quantenna.com>
The Multi-AP specification only specifies that information elements have
to be added to the Association Request and Association Response frame;
it doesn't specify anything about what should be done in case they are
missing. Previously, we rejected non-backhaul associations on a
backhaul-only BSS, and non-fronthaul associations on a fronthaul-only
BSS.
However, this makes WPS fail when fronthaul and backhaul are separate
SSIDs. Indeed, WPS for the backhaul link is performed on the *fronthaul*
SSID. Thus, the Association Request frmae used for WPS *will* contain
the Multi-AP IE indicating a backhaul STA. Rejecting that association
makes WPS fail.
Therefore, accept a multi-AP backhaul STA Association Request frame on a
fronthaul-only BSS. Still issue a warning about it, but only at level
DEBUG intead of INFO. Also change the condition checking to make it
clearer.
While we're at it, also fix the handling of unexpected bits in the
Multi-AP IE. 4 bits are reserved in the specification, so these
certainly have to be ignored. The specification also doesn't say that
setting one of the other bits is not allowed. Therefore, only report
unexpected values in the Multi-AP IE, don't reject because of it. Note
that a malformed IE (containing more than one byte) still triggers a
rejection.
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
str_token() can return NULL for the name if the remaining token contains
only the delimiter. Fix this to avoid NULL pointer dereference with a
corner case of an invalid value used in the configuration.
Fixes: ec5c39a557 ("AP: Allow identifying which passphrase station used with wpa_psk_file")
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
The new sae_password parameter [|vlanid=<VLAN ID>] can now be used to
assign stations to a specific VLAN based on which SAE Password
Identifier they use. This is similar to the WPA2-Enterprise case where
the RADIUS server can assign stations to different VLANs and the
WPA2-Personal case where vlanid parameter in wpa_psk_file is used.
Signed-off-by: Jouni Malinen <j@w1.fi>
Extend wpa_psk_file to allow an optional VLAN ID to be specified with
"vlanid=<VLAN ID>" prefix on the line. If VLAN ID is specified and the
particular wpa_psk_file entry is used for a station, that station is
bound to the specified VLAN. This can be used to operate a single
WPA2-Personal BSS with multiple VLANs based on the used passphrase/PSK.
This is similar to the WPA2-Enterprise case where the RADIUS server can
assign stations to different VLANs.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
If the ap_handle_timer() timeout is reached for a not-associated STA, do
not default to disassociating that STA first since Disassociation frame
is not really appropriate to send to a STA that is not in associated
state. Instead, skip directly to deauthentication and STA entry removal.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Add test-eapol program that can be used for fuzzing the EAPOL-Key
Supplicant and Authenticator implementations. This tool can write
Supplicant or Authenticator messages into a file as an initialization
step and for the fuzzing step, that file (with potential modifications)
can be used to replace the internally generated message contents.
The TEST_FUZZ=y build parameter is used to make a special build where a
hardcoded random number generator and hardcoded timestamp are used to
force deterministic behavior for the EAPOL-Key operations. This will
also make the implementation ignore Key MIC and AES keywrap errors to
allow processing of modified messages to continue further.
Signed-off-by: Jouni Malinen <j@w1.fi>
ieee802_11_rx_wnmsleep_req() might have been called for a short frame
that has no more payload after the Public Action field, i.e., with len
== 0. The bounds checking for the payload length was done only for the
information elements while the one octet Dialog Token field was read
unconditionally. In the original implementation, this could have
resulted in reading one octet beyond the end of the received frame data.
This case has not been reachable after the commit e0785ebbbd ("Use
more consistent Action frame RX handling in both AP mode paths"), but it
is better to address the specific issue in ieee802_11_rx_wnmsleep_req()
as well for additional protection against accidential removal of the
check and also to have something that can be merged into an older
version (pre-v2.7) if desired. The comments below apply for such older
versions where the case could have been reachable.
Depending on driver interface specific mechanism used for fetching the
frame, this could result in reading one octet beyond the end of a
stack/hash buffer or reading an uninitialized octet from within a
buffer. The actual value that was read as the Dialog Token field is not
used since the function returns immediately after having read this value
when there is no information elements following the field.
This issue was initially added in commit d32d94dbf4 ("WNM: Add
WNM-Sleep Mode implementation for AP") (with CONFIG_IEEE80211V=y build
option) and it remained in place during number of cleanup and fix
changes in this area and renaming of the build parameter to
CONFIG_WNM=y. The impacted function was not included in any default
build without one of the these optional build options being explicitly
enabled. CONFIG_WNM=y is still documented as "experimental and not
complete implementation" in hostapd/defconfig. In addition, commit
114f2830d2 ("WNM: Ignore WNM-Sleep Mode Request in wnm_sleep_mode=0
case") made this function exit before the impact read if WNM-Sleep Mode
support was not explicitly enabled in runtime configuration
(wnm_sleep_mode=1 in hostapd.conf). Commit e0785ebbbd ("Use more
consistent Action frame RX handling in both AP mode paths") made this
code unreachable in practice.
Add an explicit check that the frame has enough payload before reading
the Dialog Token field in ieee802_11_rx_wnmsleep_req().
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
This patch adds a new flag 'crl_reload_interval' to reload CRL
periodically. This can be used to reload ca_cert file and the included
CRL information on every new TLS session if difference between the last
reload and the current time in seconds is greater than
crl_reload_interval.
This reloading is used for cases where check_crl is 1 or 2 and the CRL
is included in the ca_file.
Signed-off-by: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
Signed-off-by: Jared Bents <jared.bents@rockwellcollins.com>
It is now possible to optionally specify keyid for
each wpa_psk_file entry:
keyid=something 00:00:00:00:00:00 secretpassphrase
When station connects and the passphrase it used
has an associated keyid it will be appended to the
AP-STA-CONNECTED event string:
wlan0: AP-STA-CONNECTED 00:36:76:21:dc:7b keyid=something
It's also possible to retrieve it through the control interface:
$ hostapd_cli all_sta
Selected interface 'ap0'
00:36:76:21:dc:7b
...
keyid=something
New hostapd is able to read old wpa_psk_file. However, old hostapd will
not be able to read the new wpa_psk_file if it includes keyids.
Signed-off-by: Michal Kazior <michal@plume.com>
This doesn't change any behavior on its own. It's going to be used to
expose per-station keyids and allow reloading passphrases in runtime.
Signed-off-by: Michal Kazior <michal@plume.com>
Support the new Extended Capabilities field bits 81 and 82 to indicate
whether SAe Password Identifiers are in use.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Add support for configuring parameters for the MU EDCA Parameter Set
element per IEEE P802.11ax/D3.0.
Signed-off-by: Siva Mullati <siva.mullati@intel.com>
When an interface is re-enabled after it was disabled during CAC, it
won't ever get active since hostapd is waiting for a CAC_FINISHED while
kernel side is waiting for a CMD_RADAR_DETECT to start a CAC.
This commit checks for a pending CAC when an interface is enabled and if
so restarts its DFS processing.
Signed-off-by: Zefir Kurtisi <zefir.kurtisi@neratec.com>
While the AP is configured to enable both FT-PSK and WPA-PSK, an HP
printer request both AKMs (copied from AP?) in Association Request
frame, but don't add MDIE and don't use FT. This results in the
connection failing.
Next in logs we see:
RSN: Trying to use FT, but MDIE not included
IE - hexdump(len=26): 30 18 01 00 00 0f ac 04 01 00 00 0f ac 04
02 00 00 0f ac 02 00 0f ac 04 00 00
This is seen with some HP and Epson printers. Work around this by
stripping FT AKM(s) when MDE is not present and there is still a non-FT
AKM available.
Signed-off-by: Janusz Dziedzic <janusz@plumewifi.com>
While selecting a new channel as a reaction to radar event we need to
take into account supported bandwidth for each channel provided via
nl80211. Without this modification hostapd might select an unsupported
channel that would fail during AP startup.
Signed-off-by: Dmitry Lebed <dlebed@quantenna.com>
While doing automatic channel selection we need to take into account
supported bandwidth for each channel provided via nl80211. Without this
modification hostapd might select an unsupported channel which would
fail during AP startup.
Signed-off-by: Dmitry Lebed <dlebed@quantenna.com>
This adds checks to common code to verify supported bandwidth options
for each channel using nl80211-provided info. No support of additional
modes is added, just additional checks. Such checks are needed because
driver/hardware can declare more strict limitations than declared in the
IEEE 802.11 standard. Without this patch hostapd might select
unsupported channel and that will fail because Linux kernel does check
channel bandwidth limitations.
Signed-off-by: Dmitry Lebed <dlebed@quantenna.com>
Add support for 160 MHz BW channels to automatic channel selection
algorithm. Only 36 and 100 channels are supported as 160 MHz channels.
Signed-off-by: Dmitry Lebed <lebed.dmitry@gmail.com>
FT-over-the-DS has a special case where the STA entry (and as such, the
TK) has not yet been configured to the driver depending on which driver
interface is used. For that case, allow add-STA operation to be used
(instead of set-STA). This is needed to allow mac80211-based drivers to
accept the STA parameter configuration. Since this is after a new
FT-over-DS exchange, a new TK has been derived after the last STA entry
was added to the driver, so key reinstallation is not a concern for this
case.
Fixes: 0e3bd7ac68 ("hostapd: Avoid key reinstallation in FT handshake")
Signed-off-by: Jouni Malinen <j@w1.fi>
The documentation in the hostapd.conf file says that the dynamic_vlan
variable is used to control whether VLAN assignments are accepted from a
RADIUS server. The implication seems to be that a static VLAN assignment
will come from the accept_mac_file if dynamic_vlan is set to 0, and a
dynamic assignment will come from the RADIUS server if dynamic_vlan is
set to 1. Instead, I'm seeing that the static settings from the
accept_mac_file are ignored if dynamic_vlan is set to 0, but used if
dynamic_vlan is set to 1. If dynamic_vlan is set to 1 and the RADIUS
server does not provide a VLAN, then the accept_mac_file assignment is
overridden and the STA is assigned to the default non-VLANed interface.
If my understanding of the expected behavior is correct, then I believe
the problem is in ap_sta_set_vlan(). That routine checks the
dynamic_vlan setting, but has no way of determining whether the incoming
vlan_desc is static (i.e., from accept_mac_file) or dynamic (i.e., from
a RADIUS server).
I've attached a patch that gets hostapd working as I believe it's meant
to, and updates the documentation to make the implicit behavior
explicit.
The functional changes are:
- hostapd_allowed_address() will always extract the vlan_id from the
accept_macs file. It will not update the vlan_id from the RADIUS cache
if dynamic_vlan is DISABLED.
- hostapd_acl_recv_radius() will not update the cached vlan_id if
dynamic_vlan is DISABLED.
- ieee802_1x_receive_auth() will not update the vlan_id if dynamic_vlan
is DISABLED.
More cosmetic:
Most of the delta is just moving code out of ieee802_1x_receive_auth()
into a new ieee802_1x_update_vlan() routine. While I initially did this
because the new DISABLED check introduced excessive indentation, it has
the added advantage of eliminating the vlan_description allocation and
os_memset() call for all DYNAMIC_VLAN_DISABLED configs.
I've done a couple rounds of review offline with Michael Braun (who has
done much of the work in this part of the code) and incorporated his
feedback.
If dynamic_vlan=0 (disabled), vlan assignments will be managed using the
local accept_mac_file ACL file, even if a RADIUS server is being used
for user authentication. This allows us to manage users and devices
independently.
Signed-off-by: Nils Nieuwejaar <nils.nieuwejaar@gmail.com>
After performing a successful channel switch, the AP should update its
own neighbor report element, so do this from src/ap/drv_callbacks.c
after a successful switch.
Signed-off-by: Markus Theil <markus.theil@tu-ilmenau.de>
Move functions corresponding to neighbor report elements to
src/ap/neighbor_db.[c,h] in preparation to using them after channel
switch from src/ap/drv_callbacks.c.
Signed-off-by: Markus Theil <markus.theil@tu-ilmenau.de>
Legacy ioctl() through SIOCDEVPRIVATE are deprecated. Follow the
approach taken by bridge-utils and make use of new bridge ioctl's
whenever possible.
For example, using legacy ioctl() breaks dynamic VLAN mode on 32-bit
Linux systems running 64-bit kernels.
Signed-off-by: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
If the internal EAP server is used instead of an external RADIUS server,
sm->identity does not get set. Use the identity from the internal EAP
server in such case to get the dot1xAuthSessionUserName value in STA MIB
information.
Signed-off-by: Jouni Malinen <j@w1.fi>
Try to make RSSI-based rejection of associating stations a bit less
likely to trigger false rejections by considering RSSI from the last
received Authentication frame. Association is rejected only if both the
Authentication and (Re)Association Request frames are below the RSSI
threshold.
Signed-off-by: Jouni Malinen <j@w1.fi>
An AP might reject a STA association request due to low RSSI. In such
case, the AP informs the STA the desired RSSI improvement and a retry
timeout. The STA might retry to associate even if the RSSI hasn't
improved if the retry timeout expired.
Signed-off-by: Beni Lev <beni.lev@intel.com>
Add the ability to ignore time-based CRL errors from OpenSSL by
specifying a new configuration parameter, check_crl_strict=0.
This causes the following:
- This setting does nothing when CRL checking is not enabled.
- When CRL is enabled, "strict mode" will cause CRL time errors to not
be ignored and will continue behaving as it currently does.
- When CRL is enabled, disabling strict mode will cause CRL time
errors to be ignored and will allow connections.
By default, check_crl_strict is set to 1, or strict mode, to keep
current functionality.
Signed-off-by: Sam Voss <sam.voss@rockwellcollins.com>
This makes it possible to use ECDSA certificates with EAP-TLS/TTLS/etc.
It should be noted that when using Suite B, different mechanism is used
to specify the allowed ECDH curves and this new parameter must not be
used in such cases.
Signed-off-by: Hristo Venev <hristo@venev.name>
handle_dhcp() was first trying to learn the IP address of an associated
STA before doing broadcast-to-unicast conversion. This could result in
not converting some DHCPACK messages since the address learning part
aborts processing by returning from the function in various cases.
Reorder these operations to allow broadcast-to-unicast conversion to
happen even if an associated STA entry is not updated based on a
DHCPACK.
Signed-off-by: Jouni Malinen <j@w1.fi>
These do not really get truncated in practice, but it looks like some
newer compilers warn about the prints, so silence those by checking the
result and do something a bit more useful if the output would actually
get truncated.
Signed-off-by: Jouni Malinen <j@w1.fi>
This makes it easier to integrate dynamic VLANs in custom network
configurations. The bridge name is added after the interface name in the
vlan_file line, also separated by whitespace.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Enable FTM responder and configure LCI and civic if ftm_responder
configuration option is set. Since ftm_responder configuration existed
before and was used to set extended capability bits, don't fail AP setup
flow if ftm_responder is set, but the driver doesn't advertise FTM
responder support.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
The purpose of Multi-AP specification is to enable inter-operability
across Wi-Fi access points (APs) from different vendors.
This patch introduces one new configuration parameter 'multi_ap' to
enable Multi-AP functionality and to configure the BSS as a backhaul
and/or fronthaul BSS.
Advertise vendor specific Multi-AP capabilities in (Re)Association
Response frame, if Multi-AP functionality is enabled through the
configuration parameter.
A backhaul AP must support receiving both 3addr and 4addr frames from a
backhaul STA, so create a VLAN for it just like is done for WDS, i.e.,
by calling hostapd_set_wds_sta(). Since Multi-AP requires WPA2 (never
WEP), we can safely call hostapd_set_wds_encryption() as well and we can
reuse the entire WDS condition.
To parse the Multi-AP Extension subelement, we use get_ie(): even though
that function is meant for parsing IEs, it works for subelements.
Signed-off-by: Venkateswara Naralasetty <vnaralas@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Include and verify the OCI element in WNM-Sleep Exit Request and
Response frames. In case verification fails, the frame is silently
ignored.
Signed-off-by: Mathy Vanhoef <Mathy.Vanhoef@cs.kuleuven.be>
After the network changed to a new channel, perform an SA Query with the
AP after a random delay if OCV was negotiated for the association. This
is used to confirm that we are still operating on the real operating
channel of the network. This commit is adding only the station side
functionality for this, i.e., the AP behavior is not changed to
disconnect stations with OCV that do not go through SA Query.
Signed-off-by: Mathy Vanhoef <Mathy.Vanhoef@cs.kuleuven.be>
Include an OCI element in SA Query Request and Response frames if OCV
has been negotiated.
On Linux, a kernel patch is needed to let clients correctly handle SA
Query Requests that contain an OCI element. Without this patch, the
kernel will reply to the SA Query Request itself, without verifying the
included OCI. Additionally, the SA Query Response sent by the kernel
will not include an OCI element. The correct operation of the AP does
not require a kernel patch.
Without the corresponding kernel patch, SA Query Requests sent by the
client are still valid, meaning they do include an OCI element.
Note that an AP does not require any kernel patches. In other words, SA
Query frames sent and received by the AP are properly handled, even
without a kernel patch.
As a result, the kernel patch is only required to make the client properly
process and respond to a SA Query Request from the AP. Without this
patch, the client will send a SA Query Response without an OCI element,
causing the AP to silently ignore the response and eventually disconnect
the client from the network if OCV has been negotiated to be used.
Signed-off-by: Mathy Vanhoef <Mathy.Vanhoef@cs.kuleuven.be>
