cfg80211 subsystem¶

cfg80211 is the configuration API for 802.11 devices in Linux. It bridges userspace and drivers, and offers some utility functionality associated with 802.11. cfg80211 must, directly or indirectly via mac80211, be used by all modern wireless drivers in Linux, so that they offer a consistent API through nl80211. For backward compatibility, cfg80211 also offers wireless extensions to userspace, but hides them from drivers completely.

Additionally, cfg80211 contains code to help enforce regulatory spectrum use restrictions.

Device registration¶

In order for a driver to use cfg80211, it must register the hardware device with cfg80211. This happens through a number of hardware capability structs described below.

The fundamental structure for each device is the ‘wiphy’, of which each instance describes a physical wireless device connected to the system. Each such wiphy can have zero, one, or many virtual interfaces associated with it, which need to be identified as such by pointing the network interface’s ieee80211_ptr pointer to a struct wireless_dev which further describes the wireless part of the interface, normally this struct is embedded in the network interface’s private data area. Drivers can optionally allow creating or destroying virtual interfaces on the fly, but without at least one or the ability to create some the wireless device isn’t useful.

Each wiphy structure contains device capability information, and also has a pointer to the various operations the driver offers. The definitions and structures here describe these capabilities in detail.

enum ieee80211_channel_flags¶: channel flags

Constants

IEEE80211_CHAN_DISABLED: This channel is disabled.
IEEE80211_CHAN_NO_IR: do not initiate radiation, this includes sending probe requests or beaconing.
IEEE80211_CHAN_RADAR: Radar detection is required on this channel.
IEEE80211_CHAN_NO_HT40PLUS: extension channel above this channel is not permitted.
IEEE80211_CHAN_NO_HT40MINUS: extension channel below this channel is not permitted.
IEEE80211_CHAN_NO_OFDM: OFDM is not allowed on this channel.
IEEE80211_CHAN_NO_80MHZ: If the driver supports 80 MHz on the band, this flag indicates that an 80 MHz channel cannot use this channel as the control or any of the secondary channels. This may be due to the driver or due to regulatory bandwidth restrictions.
IEEE80211_CHAN_NO_160MHZ: If the driver supports 160 MHz on the band, this flag indicates that an 160 MHz channel cannot use this channel as the control or any of the secondary channels. This may be due to the driver or due to regulatory bandwidth restrictions.
IEEE80211_CHAN_INDOOR_ONLY: see NL80211_FREQUENCY_ATTR_INDOOR_ONLY
IEEE80211_CHAN_IR_CONCURRENT: see NL80211_FREQUENCY_ATTR_IR_CONCURRENT
IEEE80211_CHAN_NO_20MHZ: 20 MHz bandwidth is not permitted on this channel.
IEEE80211_CHAN_NO_10MHZ: 10 MHz bandwidth is not permitted on this channel.

Description

Channel flags set by the regulatory control code.

struct ieee80211_channel¶: channel definition

Definition

struct ieee80211_channel {
  enum nl80211_band band;
  u16 center_freq;
  u16 hw_value;
  u32 flags;
  int max_antenna_gain;
  int max_power;
  int max_reg_power;
  bool beacon_found;
  u32 orig_flags;
  int orig_mag;
  int orig_mpwr;
  enum nl80211_dfs_state dfs_state;
  unsigned long dfs_state_entered;
  unsigned int dfs_cac_ms;
};

Members

band: band this channel belongs to.
center_freq: center frequency in MHz
hw_value: hardware-specific value for the channel
flags: channel flags from enum ieee80211_channel_flags.
max_antenna_gain: maximum antenna gain in dBi
max_power: maximum transmission power (in dBm)
max_reg_power: maximum regulatory transmission power (in dBm)
beacon_found: helper to regulatory code to indicate when a beacon has been found on this channel. Use regulatory_hint_found_beacon() to enable this, this is useful only on 5 GHz band.
orig_flags: channel flags at registration time, used by regulatory code to support devices with additional restrictions
orig_mag: internal use
orig_mpwr: internal use
dfs_state: current state of this channel. Only relevant if radar is required on this channel.
dfs_state_entered: timestamp (jiffies) when the dfs state was entered.
dfs_cac_ms: DFS CAC time in milliseconds, this is valid for DFS channels.

Description

This structure describes a single channel for use with cfg80211.

enum ieee80211_rate_flags¶: rate flags

Constants

IEEE80211_RATE_SHORT_PREAMBLE: Hardware can send with short preamble on this bitrate; only relevant in 2.4GHz band and with CCK rates.
IEEE80211_RATE_MANDATORY_A: This bitrate is a mandatory rate when used with 802.11a (on the 5 GHz band); filled by the core code when registering the wiphy.
IEEE80211_RATE_MANDATORY_B: This bitrate is a mandatory rate when used with 802.11b (on the 2.4 GHz band); filled by the core code when registering the wiphy.
IEEE80211_RATE_MANDATORY_G: This bitrate is a mandatory rate when used with 802.11g (on the 2.4 GHz band); filled by the core code when registering the wiphy.
IEEE80211_RATE_ERP_G: This is an ERP rate in 802.11g mode.
IEEE80211_RATE_SUPPORTS_5MHZ: Rate can be used in 5 MHz mode
IEEE80211_RATE_SUPPORTS_10MHZ: Rate can be used in 10 MHz mode

Description

Hardware/specification flags for rates. These are structured in a way that allows using the same bitrate structure for different bands/PHY modes.

struct ieee80211_rate¶: bitrate definition

Definition

struct ieee80211_rate {
  u32 flags;
  u16 bitrate;
  u16 hw_value;
  u16 hw_value_short;
};

Members

flags: rate-specific flags
bitrate: bitrate in units of 100 Kbps
hw_value: driver/hardware value for this rate
hw_value_short: driver/hardware value for this rate when short preamble is used

Description

This structure describes a bitrate that an 802.11 PHY can operate with. The two values hw_value and hw_value_short are only for driver use when pointers to this structure are passed around.

struct ieee80211_sta_ht_cap¶: STA’s HT capabilities

Definition

struct ieee80211_sta_ht_cap {
  u16 cap;
  bool ht_supported;
  u8 ampdu_factor;
  u8 ampdu_density;
  struct ieee80211_mcs_info mcs;
};

Members

cap: HT capabilities map as described in 802.11n spec
ht_supported: is HT supported by the STA
ampdu_factor: Maximum A-MPDU length factor
ampdu_density: Minimum A-MPDU spacing
mcs: Supported MCS rates

Description

This structure describes most essential parameters needed to describe 802.11n HT capabilities for an STA.

struct ieee80211_supported_band¶: frequency band definition

Definition

struct ieee80211_supported_band {
  struct ieee80211_channel * channels;
  struct ieee80211_rate * bitrates;
  enum nl80211_band band;
  int n_channels;
  int n_bitrates;
  struct ieee80211_sta_ht_cap ht_cap;
  struct ieee80211_sta_vht_cap vht_cap;
};

Members

channels: Array of channels the hardware can operate in in this band.
bitrates: Array of bitrates the hardware can operate with in this band. Must be sorted to give a valid “supported rates” IE, i.e. CCK rates first, then OFDM.
band: the band this structure represents
n_channels: Number of channels in channels
n_bitrates: Number of bitrates in bitrates
ht_cap: HT capabilities in this band
vht_cap: VHT capabilities in this band

Description

This structure describes a frequency band a wiphy is able to operate in.

enum cfg80211_signal_type¶: signal type

Constants

CFG80211_SIGNAL_TYPE_NONE: no signal strength information available
CFG80211_SIGNAL_TYPE_MBM: signal strength in mBm (100*dBm)
CFG80211_SIGNAL_TYPE_UNSPEC: signal strength, increasing from 0 through 100

enum wiphy_params_flags¶: set_wiphy_params bitfield values

Constants

WIPHY_PARAM_RETRY_SHORT: wiphy->retry_short has changed
WIPHY_PARAM_RETRY_LONG: wiphy->retry_long has changed
WIPHY_PARAM_FRAG_THRESHOLD: wiphy->frag_threshold has changed
WIPHY_PARAM_RTS_THRESHOLD: wiphy->rts_threshold has changed
WIPHY_PARAM_COVERAGE_CLASS: coverage class changed
WIPHY_PARAM_DYN_ACK: dynack has been enabled

enum wiphy_flags¶: wiphy capability flags

Constants

WIPHY_FLAG_NETNS_OK: if not set, do not allow changing the netns of this wiphy at all
WIPHY_FLAG_PS_ON_BY_DEFAULT: if set to true, powersave will be enabled by default – this flag will be set depending on the kernel’s default on wiphy_new(), but can be changed by the driver if it has a good reason to override the default
WIPHY_FLAG_4ADDR_AP: supports 4addr mode even on AP (with a single station on a VLAN interface)
WIPHY_FLAG_4ADDR_STATION: supports 4addr mode even as a station
WIPHY_FLAG_CONTROL_PORT_PROTOCOL: This device supports setting the control port protocol ethertype. The device also honours the control_port_no_encrypt flag.
WIPHY_FLAG_IBSS_RSN: The device supports IBSS RSN.
WIPHY_FLAG_MESH_AUTH: The device supports mesh authentication by routing auth frames to userspace. See NL80211_MESH_SETUP_USERSPACE_AUTH.
WIPHY_FLAG_SUPPORTS_FW_ROAM: The device supports roaming feature in the firmware.
WIPHY_FLAG_AP_UAPSD: The device supports uapsd on AP.
WIPHY_FLAG_SUPPORTS_TDLS: The device supports TDLS (802.11z) operation.
WIPHY_FLAG_TDLS_EXTERNAL_SETUP: The device does not handle TDLS (802.11z) link setup/discovery operations internally. Setup, discovery and teardown packets should be sent through the NL80211_CMD_TDLS_MGMT command. When this flag is not set, NL80211_CMD_TDLS_OPER should be used for asking the driver/firmware to perform a TDLS operation.
WIPHY_FLAG_HAVE_AP_SME: device integrates AP SME
WIPHY_FLAG_REPORTS_OBSS: the device will report beacons from other BSSes when there are virtual interfaces in AP mode by calling cfg80211_report_obss_beacon().
WIPHY_FLAG_AP_PROBE_RESP_OFFLOAD: When operating as an AP, the device responds to probe-requests in hardware.
WIPHY_FLAG_OFFCHAN_TX: Device supports direct off-channel TX.
WIPHY_FLAG_HAS_REMAIN_ON_CHANNEL: Device supports remain-on-channel call.
WIPHY_FLAG_SUPPORTS_5_10_MHZ: Device supports 5 MHz and 10 MHz channels.
WIPHY_FLAG_HAS_CHANNEL_SWITCH: Device supports channel switch in beaconing mode (AP, IBSS, Mesh, ...).
WIPHY_FLAG_HAS_STATIC_WEP: The device supports static WEP key installation before connection.

struct wiphy¶: wireless hardware description

Definition

struct wiphy {
  u8 perm_addr;
  u8 addr_mask;
  struct mac_address * addresses;
  const struct ieee80211_txrx_stypes * mgmt_stypes;
  const struct ieee80211_iface_combination * iface_combinations;
  int n_iface_combinations;
  u16 software_iftypes;
  u16 n_addresses;
  u16 interface_modes;
  u16 max_acl_mac_addrs;
  u32 flags;
  u32 regulatory_flags;
  u32 features;
  u8 ext_features;
  u32 ap_sme_capa;
  enum cfg80211_signal_type signal_type;
  int bss_priv_size;
  u8 max_scan_ssids;
  u8 max_sched_scan_reqs;
  u8 max_sched_scan_ssids;
  u8 max_match_sets;
  u16 max_scan_ie_len;
  u16 max_sched_scan_ie_len;
  u32 max_sched_scan_plans;
  u32 max_sched_scan_plan_interval;
  u32 max_sched_scan_plan_iterations;
  int n_cipher_suites;
  const u32 * cipher_suites;
  u8 retry_short;
  u8 retry_long;
  u32 frag_threshold;
  u32 rts_threshold;
  u8 coverage_class;
  char fw_version;
  u32 hw_version;
#ifdef CONFIG_PM
  const struct wiphy_wowlan_support * wowlan;
  struct cfg80211_wowlan * wowlan_config;
#endif
  u16 max_remain_on_channel_duration;
  u8 max_num_pmkids;
  u32 available_antennas_tx;
  u32 available_antennas_rx;
  u32 probe_resp_offload;
  const u8 * extended_capabilities;
  const u8 * extended_capabilities_mask;
  u8 extended_capabilities_len;
  const struct wiphy_iftype_ext_capab * iftype_ext_capab;
  unsigned int num_iftype_ext_capab;
  const void * privid;
  struct ieee80211_supported_band * bands;
  void (* reg_notifier) (struct wiphy *wiphy, struct regulatory_request *request);
  const struct ieee80211_regdomain __rcu * regd;
  struct device dev;
  bool registered;
  struct dentry * debugfsdir;
  const struct ieee80211_ht_cap * ht_capa_mod_mask;
  const struct ieee80211_vht_cap * vht_capa_mod_mask;
  struct list_head wdev_list;
  possible_net_t _net;
#ifdef CONFIG_CFG80211_WEXT
  const struct iw_handler_def * wext;
#endif
  const struct wiphy_coalesce_support * coalesce;
  const struct wiphy_vendor_command * vendor_commands;
  const struct nl80211_vendor_cmd_info * vendor_events;
  int n_vendor_commands;
  int n_vendor_events;
  u16 max_ap_assoc_sta;
  u8 max_num_csa_counters;
  u8 max_adj_channel_rssi_comp;
  u32 bss_select_support;
  u64 cookie_counter;
  u8 nan_supported_bands;
  char priv;
};

Members

perm_addr: permanent MAC address of this device
addr_mask: If the device supports multiple MAC addresses by masking, set this to a mask with variable bits set to 1, e.g. if the last four bits are variable then set it to 00-00-00-00-00-0f. The actual variable bits shall be determined by the interfaces added, with interfaces not matching the mask being rejected to be brought up.
addresses: If the device has more than one address, set this pointer to a list of addresses (6 bytes each). The first one will be used by default for perm_addr. In this case, the mask should be set to all-zeroes. In this case it is assumed that the device can handle the same number of arbitrary MAC addresses.
mgmt_stypes: bitmasks of frame subtypes that can be subscribed to or transmitted through nl80211, points to an array indexed by interface type
iface_combinations: Valid interface combinations array, should not list single interface types.
n_iface_combinations: number of entries in iface_combinations array.
software_iftypes: bitmask of software interface types, these are not subject to any restrictions since they are purely managed in SW.
n_addresses: number of addresses in addresses.
interface_modes: bitmask of interfaces types valid for this wiphy, must be set by driver
max_acl_mac_addrs: Maximum number of MAC addresses that the device supports for ACL.
flags: wiphy flags, see enum wiphy_flags
regulatory_flags: wiphy regulatory flags, see enum ieee80211_regulatory_flags
features: features advertised to nl80211, see enum nl80211_feature_flags.
ext_features: extended features advertised to nl80211, see enum nl80211_ext_feature_index.
ap_sme_capa: AP SME capabilities, flags from enum nl80211_ap_sme_features.
signal_type: signal type reported in struct cfg80211_bss.
bss_priv_size: each BSS struct has private data allocated with it, this variable determines its size
max_scan_ssids: maximum number of SSIDs the device can scan for in any given scan
max_sched_scan_reqs: maximum number of scheduled scan requests that the device can run concurrently.
max_sched_scan_ssids: maximum number of SSIDs the device can scan for in any given scheduled scan
max_match_sets: maximum number of match sets the device can handle when performing a scheduled scan, 0 if filtering is not supported.
max_scan_ie_len: maximum length of user-controlled IEs device can add to probe request frames transmitted during a scan, must not include fixed IEs like supported rates
max_sched_scan_ie_len: same as max_scan_ie_len, but for scheduled scans
max_sched_scan_plans: maximum number of scan plans (scan interval and number of iterations) for scheduled scan supported by the device.
max_sched_scan_plan_interval: maximum interval (in seconds) for a single scan plan supported by the device.
max_sched_scan_plan_iterations: maximum number of iterations for a single scan plan supported by the device.
n_cipher_suites: number of supported cipher suites
cipher_suites: supported cipher suites
retry_short: Retry limit for short frames (dot11ShortRetryLimit)
retry_long: Retry limit for long frames (dot11LongRetryLimit)
frag_threshold: Fragmentation threshold (dot11FragmentationThreshold); -1 = fragmentation disabled, only odd values >= 256 used
rts_threshold: RTS threshold (dot11RTSThreshold); -1 = RTS/CTS disabled
coverage_class: current coverage class
fw_version: firmware version for ethtool reporting
hw_version: hardware version for ethtool reporting
wowlan: WoWLAN support information
wowlan_config: current WoWLAN configuration; this should usually not be used since access to it is necessarily racy, use the parameter passed to the suspend() operation instead.
max_remain_on_channel_duration: Maximum time a remain-on-channel operation may request, if implemented.
max_num_pmkids: maximum number of PMKIDs supported by device
available_antennas_tx: bitmap of antennas which are available to be configured as TX antennas. Antenna configuration commands will be rejected unless this or available_antennas_rx is set.
available_antennas_rx: bitmap of antennas which are available to be configured as RX antennas. Antenna configuration commands will be rejected unless this or available_antennas_tx is set.
probe_resp_offload: Bitmap of supported protocols for probe response offloading. See enum nl80211_probe_resp_offload_support_attr. Only valid when the wiphy flag WIPHY_FLAG_AP_PROBE_RESP_OFFLOAD is set.
extended_capabilities: extended capabilities supported by the driver, additional capabilities might be supported by userspace; these are the 802.11 extended capabilities (“Extended Capabilities element”) and are in the same format as in the information element. See 802.11-2012 8.4.2.29 for the defined fields. These are the default extended capabilities to be used if the capabilities are not specified for a specific interface type in iftype_ext_capab.
extended_capabilities_mask: mask of the valid values
extended_capabilities_len: length of the extended capabilities
iftype_ext_capab: array of extended capabilities per interface type
num_iftype_ext_capab: number of interface types for which extended capabilities are specified separately.
privid: a pointer that drivers can use to identify if an arbitrary wiphy is theirs, e.g. in global notifiers
bands: information about bands/channels supported by this device
reg_notifier: the driver’s regulatory notification callback, note that if your driver uses wiphy_apply_custom_regulatory() the reg_notifier’s request can be passed as NULL
regd: the driver’s regulatory domain, if one was requested via the regulatory_hint() API. This can be used by the driver on the reg_notifier() if it chooses to ignore future regulatory domain changes caused by other drivers.
dev: (virtual) struct device for this wiphy
registered: helps synchronize suspend/resume with wiphy unregister
debugfsdir: debugfs directory used for this wiphy, will be renamed automatically on wiphy renames
ht_capa_mod_mask: Specify what ht_cap values can be over-ridden. If null, then none can be over-ridden.
vht_capa_mod_mask: Specify what VHT capabilities can be over-ridden. If null, then none can be over-ridden.
wdev_list: the list of associated (virtual) interfaces; this list must not be modified by the driver, but can be read with RTNL/RCU protection.
_net: the network namespace this wiphy currently lives in
wext: wireless extension handlers
coalesce: packet coalescing support information
vendor_commands: array of vendor commands supported by the hardware
vendor_events: array of vendor events supported by the hardware
n_vendor_commands: number of vendor commands
n_vendor_events: number of vendor events
max_ap_assoc_sta: maximum number of associated stations supported in AP mode (including P2P GO) or 0 to indicate no such limit is advertised. The driver is allowed to advertise a theoretical limit that it can reach in some cases, but may not always reach.
max_num_csa_counters: Number of supported csa_counters in beacons and probe responses. This value should be set if the driver wishes to limit the number of csa counters. Default (0) means infinite.
max_adj_channel_rssi_comp: max offset of between the channel on which the frame was sent and the channel on which the frame was heard for which the reported rssi is still valid. If a driver is able to compensate the low rssi when a frame is heard on different channel, then it should set this variable to the maximal offset for which it can compensate. This value should be set in MHz.
bss_select_support: bitmask indicating the BSS selection criteria supported by the driver in the .:c:func:connect() callback. The bit position maps to the attribute indices defined in enum nl80211_bss_select_attr.
cookie_counter: unique generic cookie counter, used to identify objects.
nan_supported_bands: bands supported by the device in NAN mode, a bitmap of enum nl80211_band values. For instance, for NL80211_BAND_2GHZ, bit 0 would be set (i.e. BIT(NL80211_BAND_2GHZ)).
priv: driver private data (sized according to wiphy_new() parameter)

struct wireless_dev¶: wireless device state

Definition

struct wireless_dev {
  struct wiphy * wiphy;
  enum nl80211_iftype iftype;
  struct list_head list;
  struct net_device * netdev;
  u32 identifier;
  struct list_head mgmt_registrations;
  spinlock_t mgmt_registrations_lock;
  struct mutex mtx;
  bool use_4addr;
  bool is_running;
  u8 address;
  u8 ssid;
  u8 ssid_len;
  u8 mesh_id_len;
  u8 mesh_id_up_len;
  struct cfg80211_conn * conn;
  struct cfg80211_cached_keys * connect_keys;
  enum ieee80211_bss_type conn_bss_type;
  u32 conn_owner_nlportid;
  struct work_struct disconnect_wk;
  u8 disconnect_bssid;
  struct list_head event_list;
  spinlock_t event_lock;
  struct cfg80211_internal_bss * current_bss;
  struct cfg80211_chan_def preset_chandef;
  struct cfg80211_chan_def chandef;
  bool ibss_fixed;
  bool ibss_dfs_possible;
  bool ps;
  int ps_timeout;
  int beacon_interval;
  u32 ap_unexpected_nlportid;
  u32 owner_nlportid;
  bool nl_owner_dead;
  bool cac_started;
  unsigned long cac_start_time;
  unsigned int cac_time_ms;
#ifdef CONFIG_CFG80211_WEXT
  struct wext;
#endif
  struct cfg80211_cqm_config * cqm_config;
};

Members

wiphy: pointer to hardware description
iftype: interface type
list: (private) Used to collect the interfaces
netdev: (private) Used to reference back to the netdev, may be NULL
identifier: (private) Identifier used in nl80211 to identify this wireless device if it has no netdev
mgmt_registrations: list of registrations for management frames
mgmt_registrations_lock: lock for the list
mtx: mutex used to lock data in this struct, may be used by drivers and some API functions require it held
use_4addr: indicates 4addr mode is used on this interface, must be set by driver (if supported) on add_interface BEFORE registering the netdev and may otherwise be used by driver read-only, will be update by cfg80211 on change_interface
is_running: true if this is a non-netdev device that has been started, e.g. the P2P Device.
address: The address for this device, valid only if netdev is NULL
ssid: (private) Used by the internal configuration code
ssid_len: (private) Used by the internal configuration code
mesh_id_len: (private) Used by the internal configuration code
mesh_id_up_len: (private) Used by the internal configuration code
conn: (private) cfg80211 software SME connection state machine data
connect_keys: (private) keys to set after connection is established
conn_bss_type: connecting/connected BSS type
conn_owner_nlportid: (private) connection owner socket port ID
disconnect_wk: (private) auto-disconnect work
disconnect_bssid: (private) the BSSID to use for auto-disconnect
event_list: (private) list for internal event processing
event_lock: (private) lock for event list
current_bss: (private) Used by the internal configuration code
preset_chandef: (private) Used by the internal configuration code to track the channel to be used for AP later
chandef: (private) Used by the internal configuration code to track the user-set channel definition.
ibss_fixed: (private) IBSS is using fixed BSSID
ibss_dfs_possible: (private) IBSS may change to a DFS channel
ps: powersave mode is enabled
ps_timeout: dynamic powersave timeout
beacon_interval: beacon interval used on this device for transmitting beacons, 0 when not valid
ap_unexpected_nlportid: (private) netlink port ID of application registered for unexpected class 3 frames (AP mode)
owner_nlportid: (private) owner socket port ID
nl_owner_dead: (private) owner socket went away
cac_started: true if DFS channel availability check has been started
cac_start_time: timestamp (jiffies) when the dfs state was entered.
cac_time_ms: CAC time in ms
wext: (private) Used by the internal wireless extensions compat code
cqm_config: (private) nl80211 RSSI monitor state

Description

For netdevs, this structure must be allocated by the driver that uses the ieee80211_ptr field in struct net_device (this is intentional so it can be allocated along with the netdev.) It need not be registered then as netdev registration will be intercepted by cfg80211 to see the new wireless device.

For non-netdev uses, it must also be allocated by the driver in response to the cfg80211 callbacks that require it, as there’s no netdev registration in that case it may not be allocated outside of callback operations that return it.

struct wiphy * wiphy_new(const struct cfg80211_ops * ops, int sizeof_priv)¶: create a new wiphy for use with cfg80211

Parameters

const struct cfg80211_ops * ops: The configuration operations for this device
int sizeof_priv: The size of the private area to allocate

Description

Create a new wiphy and associate the given operations with it. sizeof_priv bytes are allocated for private use.

Return

A pointer to the new wiphy. This pointer must be assigned to each netdev’s ieee80211_ptr for proper operation.

void wiphy_read_of_freq_limits(struct wiphy * wiphy)¶: read frequency limits from device tree

Parameters

struct wiphy * wiphy: the wireless device to get extra limits for

Description

Some devices may have extra limitations specified in DT. This may be useful for chipsets that normally support more bands but are limited due to board design (e.g. by antennas or external power amplifier).

This function reads info from DT and uses it to modify channels (disable unavailable ones). It’s usually a bad idea to use it in drivers with shared channel data as DT limitations are device specific. You should make sure to call it only if channels in wiphy are copied and can be modified without affecting other devices.

As this function access device node it has to be called after set_wiphy_dev. It also modifies channels so they have to be set first. If using this helper, call it before wiphy_register().

int wiphy_register(struct wiphy * wiphy)¶: register a wiphy with cfg80211

Parameters

struct wiphy * wiphy: The wiphy to register.

Return

A non-negative wiphy index or a negative error code.

void wiphy_unregister(struct wiphy * wiphy)¶: deregister a wiphy from cfg80211

Parameters

struct wiphy * wiphy: The wiphy to unregister.

Description

After this call, no more requests can be made with this priv pointer, but the call may sleep to wait for an outstanding request that is being handled.

void wiphy_free(struct wiphy * wiphy)¶: free wiphy

Parameters

struct wiphy * wiphy: The wiphy to free

const char * wiphy_name(const struct wiphy * wiphy)¶: get wiphy name

Parameters

const struct wiphy * wiphy: The wiphy whose name to return

Return

The name of wiphy.

struct device * wiphy_dev(struct wiphy * wiphy)¶: get wiphy dev pointer

Parameters

struct wiphy * wiphy: The wiphy whose device struct to look up

Return

The dev of wiphy.

void * wiphy_priv(struct wiphy * wiphy)¶: return priv from wiphy

Parameters

struct wiphy * wiphy: the wiphy whose priv pointer to return

Return

The priv of wiphy.

struct wiphy * priv_to_wiphy(void * priv)¶: return the wiphy containing the priv

Parameters

void * priv: a pointer previously returned by wiphy_priv

Return

The wiphy of priv.

void set_wiphy_dev(struct wiphy * wiphy, struct device * dev)¶: set device pointer for wiphy

Parameters

struct wiphy * wiphy: The wiphy whose device to bind
struct device * dev: The device to parent it to

void * wdev_priv(struct wireless_dev * wdev)¶: return wiphy priv from wireless_dev

Parameters

struct wireless_dev * wdev: The wireless device whose wiphy’s priv pointer to return

Return

The wiphy priv of wdev.

struct ieee80211_iface_limit¶: limit on certain interface types

Definition

struct ieee80211_iface_limit {
  u16 max;
  u16 types;
};

Members

max: maximum number of interfaces of these types
types: interface types (bits)

struct ieee80211_iface_combination¶: possible interface combination

Definition

struct ieee80211_iface_combination {
  const struct ieee80211_iface_limit * limits;
  u32 num_different_channels;
  u16 max_interfaces;
  u8 n_limits;
  bool beacon_int_infra_match;
  u8 radar_detect_widths;
  u8 radar_detect_regions;
  u32 beacon_int_min_gcd;
};

Members

limits

limits for the given interface types

num_different_channels

can use up to this many different channels

max_interfaces

maximum number of interfaces in total allowed in this group

n_limits

number of limitations

beacon_int_infra_match

In this combination, the beacon intervals between infrastructure and AP types must match. This is required only in special cases.

radar_detect_widths

bitmap of channel widths supported for radar detection

radar_detect_regions

bitmap of regions supported for radar detection

beacon_int_min_gcd

This interface combination supports different beacon intervals.

= 0: all beacon intervals for different interface must be same.
> 0: any beacon interval for the interface part of this combination AND GCD of all beacon intervals from beaconing interfaces of this combination must be greater or equal to this value.

Description

With this structure the driver can describe which interface combinations it supports concurrently.

Examples

Allow #STA <= 1, #AP <= 1, matching BI, channels = 1, 2 total:

struct ieee80211_iface_limit limits1[] = {
        { .max = 1, .types = BIT(NL80211_IFTYPE_STATION), },
        { .max = 1, .types = BIT(NL80211_IFTYPE_AP}, },
};
struct ieee80211_iface_combination combination1 = {
        .limits = limits1,
        .n_limits = ARRAY_SIZE(limits1),
        .max_interfaces = 2,
        .beacon_int_infra_match = true,
};

Allow #{AP, P2P-GO} <= 8, channels = 1, 8 total:

struct ieee80211_iface_limit limits2[] = {
        { .max = 8, .types = BIT(NL80211_IFTYPE_AP) |
                             BIT(NL80211_IFTYPE_P2P_GO), },
};
struct ieee80211_iface_combination combination2 = {
        .limits = limits2,
        .n_limits = ARRAY_SIZE(limits2),
        .max_interfaces = 8,
        .num_different_channels = 1,
};

Allow #STA <= 1, #{P2P-client,P2P-GO} <= 3 on two channels, 4 total.

This allows for an infrastructure connection and three P2P connections.

struct ieee80211_iface_limit limits3[] = {
        { .max = 1, .types = BIT(NL80211_IFTYPE_STATION), },
        { .max = 3, .types = BIT(NL80211_IFTYPE_P2P_GO) |
                             BIT(NL80211_IFTYPE_P2P_CLIENT), },
};
struct ieee80211_iface_combination combination3 = {
        .limits = limits3,
        .n_limits = ARRAY_SIZE(limits3),
        .max_interfaces = 4,
        .num_different_channels = 2,
};

int cfg80211_check_combinations(struct wiphy * wiphy, struct iface_combination_params * params)¶: check interface combinations

Parameters

struct wiphy * wiphy: the wiphy
struct iface_combination_params * params: the interface combinations parameter

Description

This function can be called by the driver to check whether a combination of interfaces and their types are allowed according to the interface combinations.

Actions and configuration¶

Each wireless device and each virtual interface offer a set of configuration operations and other actions that are invoked by userspace. Each of these actions is described in the operations structure, and the parameters these operations use are described separately.

Additionally, some operations are asynchronous and expect to get status information via some functions that drivers need to call.

Scanning and BSS list handling with its associated functionality is described in a separate chapter.

struct cfg80211_ops¶: backend description for wireless configuration

Definition

struct cfg80211_ops {
  int (* suspend) (struct wiphy *wiphy, struct cfg80211_wowlan *wow);
  int (* resume) (struct wiphy *wiphy);
  void (* set_wakeup) (struct wiphy *wiphy, bool enabled);
  struct wireless_dev * (* add_virtual_intf) (struct wiphy *wiphy,const char *name,unsigned char name_assign_type,enum nl80211_iftype type, struct vif_params *params);
  int (* del_virtual_intf) (struct wiphy *wiphy, struct wireless_dev *wdev);
  int (* change_virtual_intf) (struct wiphy *wiphy,struct net_device *dev,enum nl80211_iftype type, struct vif_params *params);
  int (* add_key) (struct wiphy *wiphy, struct net_device *netdev,u8 key_index, bool pairwise, const u8 *mac_addr, struct key_params *params);
  int (* get_key) (struct wiphy *wiphy, struct net_device *netdev,u8 key_index, bool pairwise, const u8 *mac_addr,void *cookie, void (*callback);
  int (* del_key) (struct wiphy *wiphy, struct net_device *netdev, u8 key_index, bool pairwise, const u8 *mac_addr);
  int (* set_default_key) (struct wiphy *wiphy,struct net_device *netdev, u8 key_index, bool unicast, bool multicast);
  int (* set_default_mgmt_key) (struct wiphy *wiphy,struct net_device *netdev, u8 key_index);
  int (* start_ap) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_ap_settings *settings);
  int (* change_beacon) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_beacon_data *info);
  int (* stop_ap) (struct wiphy *wiphy, struct net_device *dev);
  int (* add_station) (struct wiphy *wiphy, struct net_device *dev,const u8 *mac, struct station_parameters *params);
  int (* del_station) (struct wiphy *wiphy, struct net_device *dev, struct station_del_parameters *params);
  int (* change_station) (struct wiphy *wiphy, struct net_device *dev,const u8 *mac, struct station_parameters *params);
  int (* get_station) (struct wiphy *wiphy, struct net_device *dev, const u8 *mac, struct station_info *sinfo);
  int (* dump_station) (struct wiphy *wiphy, struct net_device *dev, int idx, u8 *mac, struct station_info *sinfo);
  int (* add_mpath) (struct wiphy *wiphy, struct net_device *dev, const u8 *dst, const u8 *next_hop);
  int (* del_mpath) (struct wiphy *wiphy, struct net_device *dev, const u8 *dst);
  int (* change_mpath) (struct wiphy *wiphy, struct net_device *dev, const u8 *dst, const u8 *next_hop);
  int (* get_mpath) (struct wiphy *wiphy, struct net_device *dev, u8 *dst, u8 *next_hop, struct mpath_info *pinfo);
  int (* dump_mpath) (struct wiphy *wiphy, struct net_device *dev,int idx, u8 *dst, u8 *next_hop, struct mpath_info *pinfo);
  int (* get_mpp) (struct wiphy *wiphy, struct net_device *dev, u8 *dst, u8 *mpp, struct mpath_info *pinfo);
  int (* dump_mpp) (struct wiphy *wiphy, struct net_device *dev,int idx, u8 *dst, u8 *mpp, struct mpath_info *pinfo);
  int (* get_mesh_config) (struct wiphy *wiphy,struct net_device *dev, struct mesh_config *conf);
  int (* update_mesh_config) (struct wiphy *wiphy,struct net_device *dev, u32 mask, const struct mesh_config *nconf);
  int (* join_mesh) (struct wiphy *wiphy, struct net_device *dev,const struct mesh_config *conf, const struct mesh_setup *setup);
  int (* leave_mesh) (struct wiphy *wiphy, struct net_device *dev);
  int (* join_ocb) (struct wiphy *wiphy, struct net_device *dev, struct ocb_setup *setup);
  int (* leave_ocb) (struct wiphy *wiphy, struct net_device *dev);
  int (* change_bss) (struct wiphy *wiphy, struct net_device *dev, struct bss_parameters *params);
  int (* set_txq_params) (struct wiphy *wiphy, struct net_device *dev, struct ieee80211_txq_params *params);
  int (* libertas_set_mesh_channel) (struct wiphy *wiphy,struct net_device *dev, struct ieee80211_channel *chan);
  int (* set_monitor_channel) (struct wiphy *wiphy, struct cfg80211_chan_def *chandef);
  int (* scan) (struct wiphy *wiphy, struct cfg80211_scan_request *request);
  void (* abort_scan) (struct wiphy *wiphy, struct wireless_dev *wdev);
  int (* auth) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_auth_request *req);
  int (* assoc) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_assoc_request *req);
  int (* deauth) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_deauth_request *req);
  int (* disassoc) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_disassoc_request *req);
  int (* connect) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_connect_params *sme);
  int (* update_connect_params) (struct wiphy *wiphy,struct net_device *dev,struct cfg80211_connect_params *sme, u32 changed);
  int (* disconnect) (struct wiphy *wiphy, struct net_device *dev, u16 reason_code);
  int (* join_ibss) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_ibss_params *params);
  int (* leave_ibss) (struct wiphy *wiphy, struct net_device *dev);
  int (* set_mcast_rate) (struct wiphy *wiphy, struct net_device *dev, int rate[NUM_NL80211_BANDS]);
  int (* set_wiphy_params) (struct wiphy *wiphy, u32 changed);
  int (* set_tx_power) (struct wiphy *wiphy, struct wireless_dev *wdev, enum nl80211_tx_power_setting type, int mbm);
  int (* get_tx_power) (struct wiphy *wiphy, struct wireless_dev *wdev, int *dbm);
  int (* set_wds_peer) (struct wiphy *wiphy, struct net_device *dev, const u8 *addr);
  void (* rfkill_poll) (struct wiphy *wiphy);
#ifdef CONFIG_NL80211_TESTMODE
  int (* testmode_cmd) (struct wiphy *wiphy, struct wireless_dev *wdev, void *data, int len);
  int (* testmode_dump) (struct wiphy *wiphy, struct sk_buff *skb,struct netlink_callback *cb, void *data, int len);
#endif
  int (* set_bitrate_mask) (struct wiphy *wiphy,struct net_device *dev,const u8 *peer, const struct cfg80211_bitrate_mask *mask);
  int (* dump_survey) (struct wiphy *wiphy, struct net_device *netdev, int idx, struct survey_info *info);
  int (* set_pmksa) (struct wiphy *wiphy, struct net_device *netdev, struct cfg80211_pmksa *pmksa);
  int (* del_pmksa) (struct wiphy *wiphy, struct net_device *netdev, struct cfg80211_pmksa *pmksa);
  int (* flush_pmksa) (struct wiphy *wiphy, struct net_device *netdev);
  int (* remain_on_channel) (struct wiphy *wiphy,struct wireless_dev *wdev,struct ieee80211_channel *chan,unsigned int duration, u64 *cookie);
  int (* cancel_remain_on_channel) (struct wiphy *wiphy,struct wireless_dev *wdev, u64 cookie);
  int (* mgmt_tx) (struct wiphy *wiphy, struct wireless_dev *wdev,struct cfg80211_mgmt_tx_params *params, u64 *cookie);
  int (* mgmt_tx_cancel_wait) (struct wiphy *wiphy,struct wireless_dev *wdev, u64 cookie);
  int (* set_power_mgmt) (struct wiphy *wiphy, struct net_device *dev, bool enabled, int timeout);
  int (* set_cqm_rssi_config) (struct wiphy *wiphy,struct net_device *dev, s32 rssi_thold, u32 rssi_hyst);
  int (* set_cqm_rssi_range_config) (struct wiphy *wiphy,struct net_device *dev, s32 rssi_low, s32 rssi_high);
  int (* set_cqm_txe_config) (struct wiphy *wiphy,struct net_device *dev, u32 rate, u32 pkts, u32 intvl);
  void (* mgmt_frame_register) (struct wiphy *wiphy,struct wireless_dev *wdev, u16 frame_type, bool reg);
  int (* set_antenna) (struct wiphy *wiphy, u32 tx_ant, u32 rx_ant);
  int (* get_antenna) (struct wiphy *wiphy, u32 *tx_ant, u32 *rx_ant);
  int (* sched_scan_start) (struct wiphy *wiphy,struct net_device *dev, struct cfg80211_sched_scan_request *request);
  int (* sched_scan_stop) (struct wiphy *wiphy, struct net_device *dev, u64 reqid);
  int (* set_rekey_data) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_gtk_rekey_data *data);
  int (* tdls_mgmt) (struct wiphy *wiphy, struct net_device *dev,const u8 *peer, u8 action_code, u8 dialog_token,u16 status_code, u32 peer_capability, bool initiator, const u8 *buf, size_t len);
  int (* tdls_oper) (struct wiphy *wiphy, struct net_device *dev, const u8 *peer, enum nl80211_tdls_operation oper);
  int (* probe_client) (struct wiphy *wiphy, struct net_device *dev, const u8 *peer, u64 *cookie);
  int (* set_noack_map) (struct wiphy *wiphy,struct net_device *dev, u16 noack_map);
  int (* get_channel) (struct wiphy *wiphy,struct wireless_dev *wdev, struct cfg80211_chan_def *chandef);
  int (* start_p2p_device) (struct wiphy *wiphy, struct wireless_dev *wdev);
  void (* stop_p2p_device) (struct wiphy *wiphy, struct wireless_dev *wdev);
  int (* set_mac_acl) (struct wiphy *wiphy, struct net_device *dev, const struct cfg80211_acl_data *params);
  int (* start_radar_detection) (struct wiphy *wiphy,struct net_device *dev,struct cfg80211_chan_def *chandef, u32 cac_time_ms);
  int (* update_ft_ies) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_update_ft_ies_params *ftie);
  int (* crit_proto_start) (struct wiphy *wiphy,struct wireless_dev *wdev,enum nl80211_crit_proto_id protocol, u16 duration);
  void (* crit_proto_stop) (struct wiphy *wiphy, struct wireless_dev *wdev);
  int (* set_coalesce) (struct wiphy *wiphy, struct cfg80211_coalesce *coalesce);
  int (* channel_switch) (struct wiphy *wiphy,struct net_device *dev, struct cfg80211_csa_settings *params);
  int (* set_qos_map) (struct wiphy *wiphy,struct net_device *dev, struct cfg80211_qos_map *qos_map);
  int (* set_ap_chanwidth) (struct wiphy *wiphy, struct net_device *dev, struct cfg80211_chan_def *chandef);
  int (* add_tx_ts) (struct wiphy *wiphy, struct net_device *dev,u8 tsid, const u8 *peer, u8 user_prio, u16 admitted_time);
  int (* del_tx_ts) (struct wiphy *wiphy, struct net_device *dev, u8 tsid, const u8 *peer);
  int (* tdls_channel_switch) (struct wiphy *wiphy,struct net_device *dev,const u8 *addr, u8 oper_class, struct cfg80211_chan_def *chandef);
  void (* tdls_cancel_channel_switch) (struct wiphy *wiphy,struct net_device *dev, const u8 *addr);
  int (* start_nan) (struct wiphy *wiphy, struct wireless_dev *wdev, struct cfg80211_nan_conf *conf);
  void (* stop_nan) (struct wiphy *wiphy, struct wireless_dev *wdev);
  int (* add_nan_func) (struct wiphy *wiphy, struct wireless_dev *wdev, struct cfg80211_nan_func *nan_func);
  void (* del_nan_func) (struct wiphy *wiphy, struct wireless_dev *wdev, u64 cookie);
  int (* nan_change_conf) (struct wiphy *wiphy,struct wireless_dev *wdev,struct cfg80211_nan_conf *conf, u32 changes);
  int (* set_multicast_to_unicast) (struct wiphy *wiphy,struct net_device *dev, const bool enabled);
  int (* set_pmk) (struct wiphy *wiphy, struct net_device *dev, const struct cfg80211_pmk_conf *conf);
  int (* del_pmk) (struct wiphy *wiphy, struct net_device *dev, const u8 *aa);
};

Members

suspend: wiphy device needs to be suspended. The variable wow will be NULL or contain the enabled Wake-on-Wireless triggers that are configured for the device.
resume: wiphy device needs to be resumed
set_wakeup: Called when WoWLAN is enabled/disabled, use this callback to call device_set_wakeup_enable() to enable/disable wakeup from the device.
add_virtual_intf: create a new virtual interface with the given name, must set the struct wireless_dev’s iftype. Beware: You must create the new netdev in the wiphy’s network namespace! Returns the struct wireless_dev, or an ERR_PTR. For P2P device wdevs, the driver must also set the address member in the wdev.
del_virtual_intf: remove the virtual interface
change_virtual_intf: change type/configuration of virtual interface, keep the struct wireless_dev’s iftype updated.
add_key: add a key with the given parameters. mac_addr will be NULL when adding a group key.
get_key: get information about the key with the given parameters. mac_addr will be NULL when requesting information for a group key. All pointers given to the callback function need not be valid after it returns. This function should return an error if it is not possible to retrieve the key, -ENOENT if it doesn’t exist.
del_key: remove a key given the mac_addr (NULL for a group key) and key_index, return -ENOENT if the key doesn’t exist.
set_default_key: set the default key on an interface
set_default_mgmt_key: set the default management frame key on an interface
start_ap: Start acting in AP mode defined by the parameters.
change_beacon: Change the beacon parameters for an access point mode interface. This should reject the call when AP mode wasn’t started.
stop_ap: Stop being an AP, including stopping beaconing.
add_station: Add a new station.
del_station: Remove a station
change_station: Modify a given station. Note that flags changes are not much validated in cfg80211, in particular the auth/assoc/authorized flags might come to the driver in invalid combinations – make sure to check them, also against the existing state! Drivers must call cfg80211_check_station_change() to validate the information.
get_station: get station information for the station identified by mac
dump_station: dump station callback – resume dump at index idx
add_mpath: add a fixed mesh path
del_mpath: delete a given mesh path
change_mpath: change a given mesh path
get_mpath: get a mesh path for the given parameters
dump_mpath: dump mesh path callback – resume dump at index idx
get_mpp: get a mesh proxy path for the given parameters
dump_mpp: dump mesh proxy path callback – resume dump at index idx
get_mesh_config: Get the current mesh configuration
update_mesh_config: Update mesh parameters on a running mesh. The mask is a bitfield which tells us which parameters to set, and which to leave alone.
join_mesh: join the mesh network with the specified parameters (invoked with the wireless_dev mutex held)
leave_mesh: leave the current mesh network (invoked with the wireless_dev mutex held)
join_ocb: join the OCB network with the specified parameters (invoked with the wireless_dev mutex held)
leave_ocb: leave the current OCB network (invoked with the wireless_dev mutex held)
change_bss: Modify parameters for a given BSS.
set_txq_params: Set TX queue parameters
libertas_set_mesh_channel: Only for backward compatibility for libertas, as it doesn’t implement join_mesh and needs to set the channel to join the mesh instead.
set_monitor_channel: Set the monitor mode channel for the device. If other interfaces are active this callback should reject the configuration. If no interfaces are active or the device is down, the channel should be stored for when a monitor interface becomes active.
scan: Request to do a scan. If returning zero, the scan request is given the driver, and will be valid until passed to cfg80211_scan_done(). For scan results, call cfg80211_inform_bss(); you can call this outside the scan/scan_done bracket too.
abort_scan: Tell the driver to abort an ongoing scan. The driver shall indicate the status of the scan through cfg80211_scan_done().
auth: Request to authenticate with the specified peer (invoked with the wireless_dev mutex held)
assoc: Request to (re)associate with the specified peer (invoked with the wireless_dev mutex held)
deauth: Request to deauthenticate from the specified peer (invoked with the wireless_dev mutex held)
disassoc: Request to disassociate from the specified peer (invoked with the wireless_dev mutex held)
connect: Connect to the ESS with the specified parameters. When connected, call cfg80211_connect_result()/cfg80211_connect_bss() with status code WLAN_STATUS_SUCCESS. If the connection fails for some reason, call cfg80211_connect_result()/cfg80211_connect_bss() with the status code from the AP or cfg80211_connect_timeout() if no frame with status code was received. The driver is allowed to roam to other BSSes within the ESS when the other BSS matches the connect parameters. When such roaming is initiated by the driver, the driver is expected to verify that the target matches the configured security parameters and to use Reassociation Request frame instead of Association Request frame. The connect function can also be used to request the driver to perform a specific roam when connected to an ESS. In that case, the prev_bssid parameter is set to the BSSID of the currently associated BSS as an indication of requesting reassociation. In both the driver-initiated and new connect() call initiated roaming cases, the result of roaming is indicated with a call to cfg80211_roamed(). (invoked with the wireless_dev mutex held)
update_connect_params: Update the connect parameters while connected to a BSS. The updated parameters can be used by driver/firmware for subsequent BSS selection (roaming) decisions and to form the Authentication/(Re)Association Request frames. This call does not request an immediate disassociation or reassociation with the current BSS, i.e., this impacts only subsequent (re)associations. The bits in changed are defined in enum cfg80211_connect_params_changed. (invoked with the wireless_dev mutex held)
disconnect: Disconnect from the BSS/ESS or stop connection attempts if connection is in progress. Once done, call cfg80211_disconnected() in case connection was already established (invoked with the wireless_dev mutex held), otherwise call cfg80211_connect_timeout().
join_ibss: Join the specified IBSS (or create if necessary). Once done, call cfg80211_ibss_joined(), also call that function when changing BSSID due to a merge. (invoked with the wireless_dev mutex held)
leave_ibss: Leave the IBSS. (invoked with the wireless_dev mutex held)
set_mcast_rate: Set the specified multicast rate (only if vif is in ADHOC or MESH mode)
set_wiphy_params: Notify that wiphy parameters have changed; changed bitfield (see enum wiphy_params_flags) describes which values have changed. The actual parameter values are available in struct wiphy. If returning an error, no value should be changed.
set_tx_power: set the transmit power according to the parameters, the power passed is in mBm, to get dBm use MBM_TO_DBM(). The wdev may be NULL if power was set for the wiphy, and will always be NULL unless the driver supports per-vif TX power (as advertised by the nl80211 feature flag.)
get_tx_power: store the current TX power into the dbm variable; return 0 if successful
set_wds_peer: set the WDS peer for a WDS interface
rfkill_poll: polls the hw rfkill line, use cfg80211 reporting functions to adjust rfkill hw state
testmode_cmd: run a test mode command; wdev may be NULL
testmode_dump: Implement a test mode dump. The cb->args[2] and up may be used by the function, but 0 and 1 must not be touched. Additionally, return error codes other than -ENOBUFS and -ENOENT will terminate the dump and return to userspace with an error, so be careful. If any data was passed in from userspace then the data/len arguments will be present and point to the data contained in NL80211_ATTR_TESTDATA.
set_bitrate_mask: set the bitrate mask configuration
dump_survey: get site survey information.
set_pmksa: Cache a PMKID for a BSSID. This is mostly useful for fullmac devices running firmwares capable of generating the (re) association RSN IE. It allows for faster roaming between WPA2 BSSIDs.
del_pmksa: Delete a cached PMKID.
flush_pmksa: Flush all cached PMKIDs.
remain_on_channel: Request the driver to remain awake on the specified channel for the specified duration to complete an off-channel operation (e.g., public action frame exchange). When the driver is ready on the requested channel, it must indicate this with an event notification by calling cfg80211_ready_on_channel().
cancel_remain_on_channel: Cancel an on-going remain-on-channel operation. This allows the operation to be terminated prior to timeout based on the duration value.
mgmt_tx: Transmit a management frame.
mgmt_tx_cancel_wait: Cancel the wait time from transmitting a management frame on another channel
set_power_mgmt: Configure WLAN power management. A timeout value of -1 allows the driver to adjust the dynamic ps timeout value.
set_cqm_rssi_config: Configure connection quality monitor RSSI threshold. After configuration, the driver should (soon) send an event indicating the current level is above/below the configured threshold; this may need some care when the configuration is changed (without first being disabled.)
set_cqm_rssi_range_config: Configure two RSSI thresholds in the connection quality monitor. An event is to be sent only when the signal level is found to be outside the two values. The driver should set NL80211_EXT_FEATURE_CQM_RSSI_LIST if this method is implemented. If it is provided then there’s no point providing set_cqm_rssi_config.
set_cqm_txe_config: Configure connection quality monitor TX error thresholds.
mgmt_frame_register: Notify driver that a management frame type was registered. The callback is allowed to sleep.
set_antenna: Set antenna configuration (tx_ant, rx_ant) on the device. Parameters are bitmaps of allowed antennas to use for TX/RX. Drivers may reject TX/RX mask combinations they cannot support by returning -EINVAL (also see nl80211.h NL80211_ATTR_WIPHY_ANTENNA_TX).
get_antenna: Get current antenna configuration from device (tx_ant, rx_ant).
sched_scan_start: Tell the driver to start a scheduled scan.
sched_scan_stop: Tell the driver to stop an ongoing scheduled scan with given request id. This call must stop the scheduled scan and be ready for starting a new one before it returns, i.e. sched_scan_start may be called immediately after that again and should not fail in that case. The driver should not call cfg80211_sched_scan_stopped() for a requested stop (when this method returns 0).
set_rekey_data: give the data necessary for GTK rekeying to the driver
tdls_mgmt: Transmit a TDLS management frame.
tdls_oper: Perform a high-level TDLS operation (e.g. TDLS link setup).
probe_client: probe an associated client, must return a cookie that it later passes to cfg80211_probe_status().
set_noack_map: Set the NoAck Map for the TIDs.
get_channel: Get the current operating channel for the virtual interface. For monitor interfaces, it should return NULL unless there’s a single current monitoring channel.
start_p2p_device: Start the given P2P device.
stop_p2p_device: Stop the given P2P device.
set_mac_acl: Sets MAC address control list in AP and P2P GO mode. Parameters include ACL policy, an array of MAC address of stations and the number of MAC addresses. If there is already a list in driver this new list replaces the existing one. Driver has to clear its ACL when number of MAC addresses entries is passed as 0. Drivers which advertise the support for MAC based ACL have to implement this callback.
start_radar_detection: Start radar detection in the driver.
update_ft_ies: Provide updated Fast BSS Transition information to the driver. If the SME is in the driver/firmware, this information can be used in building Authentication and Reassociation Request frames.
crit_proto_start: Indicates a critical protocol needs more link reliability for a given duration (milliseconds). The protocol is provided so the driver can take the most appropriate actions.
crit_proto_stop: Indicates critical protocol no longer needs increased link reliability. This operation can not fail.
set_coalesce: Set coalesce parameters.
channel_switch: initiate channel-switch procedure (with CSA). Driver is responsible for veryfing if the switch is possible. Since this is inherently tricky driver may decide to disconnect an interface later with cfg80211_stop_iface(). This doesn’t mean driver can accept everything. It should do it’s best to verify requests and reject them as soon as possible.
set_qos_map: Set QoS mapping information to the driver
set_ap_chanwidth: Set the AP (including P2P GO) mode channel width for the given interface This is used e.g. for dynamic HT 20/40 MHz channel width changes during the lifetime of the BSS.
add_tx_ts: validate (if admitted_time is 0) or add a TX TS to the device with the given parameters; action frame exchange has been handled by userspace so this just has to modify the TX path to take the TS into account. If the admitted time is 0 just validate the parameters to make sure the session can be created at all; it is valid to just always return success for that but that may result in inefficient behaviour (handshake with the peer followed by immediate teardown when the addition is later rejected)
del_tx_ts: remove an existing TX TS
tdls_channel_switch: Start channel-switching with a TDLS peer. The driver is responsible for continually initiating channel-switching operations and returning to the base channel for communication with the AP.
tdls_cancel_channel_switch: Stop channel-switching with a TDLS peer. Both peers must be on the base channel when the call completes.
start_nan: Start the NAN interface.
stop_nan: Stop the NAN interface.
add_nan_func: Add a NAN function. Returns negative value on failure. On success nan_func ownership is transferred to the driver and it may access it outside of the scope of this function. The driver should free the nan_func when no longer needed by calling cfg80211_free_nan_func(). On success the driver should assign an instance_id in the provided nan_func.
del_nan_func: Delete a NAN function.
nan_change_conf: changes NAN configuration. The changed parameters must be specified in changes (using enum cfg80211_nan_conf_changes); All other parameters must be ignored.
set_multicast_to_unicast: configure multicast to unicast conversion for BSS
set_pmk: configure the PMK to be used for offloaded 802.1X 4-Way handshake. If not deleted through del_pmk the PMK remains valid until disconnect upon which the driver should clear it. (invoked with the wireless_dev mutex held)
del_pmk: delete the previously configured PMK for the given authenticator. (invoked with the wireless_dev mutex held)

Description

This struct is registered by fullmac card drivers and/or wireless stacks in order to handle configuration requests on their interfaces.

All callbacks except where otherwise noted should return 0 on success or a negative error code.

All operations are currently invoked under rtnl for consistency with the wireless extensions but this is subject to reevaluation as soon as this code is used more widely and we have a first user without wext.

struct vif_params¶: describes virtual interface parameters

Definition

struct vif_params {
  u32 flags;
  int use_4addr;
  u8 macaddr;
  const u8 * vht_mumimo_groups;
  const u8 * vht_mumimo_follow_addr;
};

Members

flags: monitor interface flags, unchanged if 0, otherwise MONITOR_FLAG_CHANGED will be set
use_4addr: use 4-address frames
macaddr: address to use for this virtual interface. If this parameter is set to zero address the driver may determine the address as needed. This feature is only fully supported by drivers that enable the NL80211_FEATURE_MAC_ON_CREATE flag. Others may support creating * only p2p devices with specified MAC.
vht_mumimo_groups: MU-MIMO groupID, used for monitoring MU-MIMO packets belonging to that MU-MIMO groupID; NULL if not changed
vht_mumimo_follow_addr: MU-MIMO follow address, used for monitoring MU-MIMO packets going to the specified station; NULL if not changed

struct key_params¶: key information

Definition

struct key_params {
  const u8 * key;
  const u8 * seq;
  int key_len;
  int seq_len;
  u32 cipher;
};

Members

key: key material
seq: sequence counter (IV/PN) for TKIP and CCMP keys, only used with the get_key() callback, must be in little endian, length given by seq_len.
key_len: length of key material
seq_len: length of seq.
cipher: cipher suite selector

Description

Information about a key

enum survey_info_flags¶: survey information flags

Constants

SURVEY_INFO_NOISE_DBM: noise (in dBm) was filled in
SURVEY_INFO_IN_USE: channel is currently being used
SURVEY_INFO_TIME: active time (in ms) was filled in
SURVEY_INFO_TIME_BUSY: busy time was filled in
SURVEY_INFO_TIME_EXT_BUSY: extension channel busy time was filled in
SURVEY_INFO_TIME_RX: receive time was filled in
SURVEY_INFO_TIME_TX: transmit time was filled in
SURVEY_INFO_TIME_SCAN: scan time was filled in

Description

Used by the driver to indicate which info in struct survey_info it has filled in during the get_survey().

struct survey_info¶: channel survey response

Definition

struct survey_info {
  struct ieee80211_channel * channel;
  u64 time;
  u64 time_busy;
  u64 time_ext_busy;
  u64 time_rx;
  u64 time_tx;
  u64 time_scan;
  u32 filled;
  s8 noise;
};

Members

channel: the channel this survey record reports, may be NULL for a single record to report global statistics
time: amount of time in ms the radio was turn on (on the channel)
time_busy: amount of time the primary channel was sensed busy
time_ext_busy: amount of time the extension channel was sensed busy
time_rx: amount of time the radio spent receiving data
time_tx: amount of time the radio spent transmitting data
time_scan: amount of time the radio spent for scanning
filled: bitflag of flags from enum survey_info_flags
noise: channel noise in dBm. This and all following fields are optional

Description

Used by dump_survey() to report back per-channel survey information.

This structure can later be expanded with things like channel duty cycle etc.

struct cfg80211_beacon_data¶: beacon data

Definition

struct cfg80211_beacon_data {
  const u8 * head;
  const u8 * tail;
  const u8 * beacon_ies;
  const u8 * proberesp_ies;
  const u8 * assocresp_ies;
  const u8 * probe_resp;
  size_t head_len;
  size_t tail_len;
  size_t beacon_ies_len;
  size_t proberesp_ies_len;
  size_t assocresp_ies_len;
  size_t probe_resp_len;
};

Members

head: head portion of beacon (before TIM IE) or NULL if not changed
tail: tail portion of beacon (after TIM IE) or NULL if not changed
beacon_ies: extra information element(s) to add into Beacon frames or NULL
proberesp_ies: extra information element(s) to add into Probe Response frames or NULL
assocresp_ies: extra information element(s) to add into (Re)Association Response frames or NULL
probe_resp: probe response template (AP mode only)
head_len: length of head
tail_len: length of tail
beacon_ies_len: length of beacon_ies in octets
proberesp_ies_len: length of proberesp_ies in octets
assocresp_ies_len: length of assocresp_ies in octets
probe_resp_len: length of probe response template (probe_resp)

struct cfg80211_ap_settings¶: AP configuration

Definition

struct cfg80211_ap_settings {
  struct cfg80211_chan_def chandef;
  struct cfg80211_beacon_data beacon;
  int beacon_interval;
  int dtim_period;
  const u8 * ssid;
  size_t ssid_len;
  enum nl80211_hidden_ssid hidden_ssid;
  struct cfg80211_crypto_settings crypto;
  bool privacy;
  enum nl80211_auth_type auth_type;
  enum nl80211_smps_mode smps_mode;
  int inactivity_timeout;
  u8 p2p_ctwindow;
  bool p2p_opp_ps;
  const struct cfg80211_acl_data * acl;
  bool pbss;
  struct cfg80211_bitrate_mask beacon_rate;
  const struct ieee80211_ht_cap * ht_cap;
  const struct ieee80211_vht_cap * vht_cap;
  bool ht_required;
  bool vht_required;
};

Members

chandef: defines the channel to use
beacon: beacon data
beacon_interval: beacon interval
dtim_period: DTIM period
ssid: SSID to be used in the BSS (note: may be NULL if not provided from user space)
ssid_len: length of ssid
hidden_ssid: whether to hide the SSID in Beacon/Probe Response frames
crypto: crypto settings
privacy: the BSS uses privacy
auth_type: Authentication type (algorithm)
smps_mode: SMPS mode
inactivity_timeout: time in seconds to determine station’s inactivity.
p2p_ctwindow: P2P CT Window
p2p_opp_ps: P2P opportunistic PS
acl: ACL configuration used by the drivers which has support for MAC address based access control
pbss: If set, start as a PCP instead of AP. Relevant for DMG networks.
beacon_rate: bitrate to be used for beacons
ht_cap: HT capabilities (or NULL if HT isn’t enabled)
vht_cap: VHT capabilities (or NULL if VHT isn’t enabled)
ht_required: stations must support HT
vht_required: stations must support VHT

Description

Used to configure an AP interface.

struct station_parameters¶: station parameters

Definition

struct station_parameters {
  const u8 * supported_rates;
  struct net_device * vlan;
  u32 sta_flags_mask;
  u32 sta_flags_set;
  u32 sta_modify_mask;
  int listen_interval;
  u16 aid;
  u16 peer_aid;
  u8 supported_rates_len;
  u8 plink_action;
  u8 plink_state;
  const struct ieee80211_ht_cap * ht_capa;
  const struct ieee80211_vht_cap * vht_capa;
  u8 uapsd_queues;
  u8 max_sp;
  enum nl80211_mesh_power_mode local_pm;
  u16 capability;
  const u8 * ext_capab;
  u8 ext_capab_len;
  const u8 * supported_channels;
  u8 supported_channels_len;
  const u8 * supported_oper_classes;
  u8 supported_oper_classes_len;
  u8 opmode_notif;
  bool opmode_notif_used;
  int support_p2p_ps;
};

Members

supported_rates: supported rates in IEEE 802.11 format (or NULL for no change)
vlan: vlan interface station should belong to
sta_flags_mask: station flags that changed (bitmask of BIT(NL80211_STA_FLAG_...))
sta_flags_set: station flags values (bitmask of BIT(NL80211_STA_FLAG_...))
sta_modify_mask: bitmap indicating which parameters changed (for those that don’t have a natural “no change” value), see enum station_parameters_apply_mask
listen_interval: listen interval or -1 for no change
aid: AID or zero for no change
peer_aid: mesh peer AID or zero for no change
supported_rates_len: number of supported rates
plink_action: plink action to take
plink_state: set the peer link state for a station
ht_capa: HT capabilities of station
vht_capa: VHT capabilities of station
uapsd_queues: bitmap of queues configured for uapsd. same format as the AC bitmap in the QoS info field
max_sp: max Service Period. same format as the MAX_SP in the QoS info field (but already shifted down)
local_pm: local link-specific mesh power save mode (no change when set to unknown)
capability: station capability
ext_capab: extended capabilities of the station
ext_capab_len: number of extended capabilities
supported_channels: supported channels in IEEE 802.11 format
supported_channels_len: number of supported channels
supported_oper_classes: supported oper classes in IEEE 802.11 format
supported_oper_classes_len: number of supported operating classes
opmode_notif: operating mode field from Operating Mode Notification
opmode_notif_used: information if operating mode field is used
support_p2p_ps: information if station supports P2P PS mechanism

Description

Used to change and create a new station.

enum rate_info_flags¶: bitrate info flags

Constants

RATE_INFO_FLAGS_MCS: mcs field filled with HT MCS
RATE_INFO_FLAGS_VHT_MCS: mcs field filled with VHT MCS
RATE_INFO_FLAGS_SHORT_GI: 400ns guard interval
RATE_INFO_FLAGS_60G: 60GHz MCS

Description

Used by the driver to indicate the specific rate transmission type for 802.11n transmissions.

struct rate_info¶: bitrate information

Definition

struct rate_info {
  u8 flags;
  u8 mcs;
  u16 legacy;
  u8 nss;
  u8 bw;
};

Members

flags: bitflag of flags from enum rate_info_flags
mcs: mcs index if struct describes a 802.11n bitrate
legacy: bitrate in 100kbit/s for 802.11abg
nss: number of streams (VHT only)
bw: bandwidth (from enum rate_info_bw)

Description

Information about a receiving or transmitting bitrate

struct station_info¶: station information

Definition

struct station_info {
  u64 filled;
  u32 connected_time;
  u32 inactive_time;
  u64 rx_bytes;
  u64 tx_bytes;
  u16 llid;
  u16 plid;
  u8 plink_state;
  s8 signal;
  s8 signal_avg;
  u8 chains;
  s8 chain_signal;
  s8 chain_signal_avg;
  struct rate_info txrate;
  struct rate_info rxrate;
  u32 rx_packets;
  u32 tx_packets;
  u32 tx_retries;
  u32 tx_failed;
  u32 rx_dropped_misc;
  struct sta_bss_parameters bss_param;
  struct nl80211_sta_flag_update sta_flags;
  int generation;
  const u8 * assoc_req_ies;
  size_t assoc_req_ies_len;
  u32 beacon_loss_count;
  s64 t_offset;
  enum nl80211_mesh_power_mode local_pm;
  enum nl80211_mesh_power_mode peer_pm;
  enum nl80211_mesh_power_mode nonpeer_pm;
  u32 expected_throughput;
  u64 rx_beacon;
  u64 rx_duration;
  u8 rx_beacon_signal_avg;
  struct cfg80211_tid_stats pertid;
};

Members

filled: bitflag of flags using the bits of enum nl80211_sta_info to indicate the relevant values in this struct for them
connected_time: time(in secs) since a station is last connected
inactive_time: time since last station activity (tx/rx) in milliseconds
rx_bytes: bytes (size of MPDUs) received from this station
tx_bytes: bytes (size of MPDUs) transmitted to this station
llid: mesh local link id
plid: mesh peer link id
plink_state: mesh peer link state
signal: The signal strength, type depends on the wiphy’s signal_type. For CFG80211_SIGNAL_TYPE_MBM, value is expressed in _dBm_.
signal_avg: Average signal strength, type depends on the wiphy’s signal_type. For CFG80211_SIGNAL_TYPE_MBM, value is expressed in _dBm_.
chains: bitmask for filled values in chain_signal, chain_signal_avg
chain_signal: per-chain signal strength of last received packet in dBm
chain_signal_avg: per-chain signal strength average in dBm
txrate: current unicast bitrate from this station
rxrate: current unicast bitrate to this station
rx_packets: packets (MSDUs & MMPDUs) received from this station
tx_packets: packets (MSDUs & MMPDUs) transmitted to this station
tx_retries: cumulative retry counts (MPDUs)
tx_failed: number of failed transmissions (MPDUs) (retries exceeded, no ACK)
rx_dropped_misc: Dropped for un-specified reason.
bss_param: current BSS parameters
sta_flags: station flags mask & values
generation: generation number for nl80211 dumps. This number should increase every time the list of stations changes, i.e. when a station is added or removed, so that userspace can tell whether it got a consistent snapshot.
assoc_req_ies: IEs from (Re)Association Request. This is used only when in AP mode with drivers that do not use user space MLME/SME implementation. The information is provided for the cfg80211_new_sta() calls to notify user space of the IEs.
assoc_req_ies_len: Length of assoc_req_ies buffer in octets.
beacon_loss_count: Number of times beacon loss event has triggered.
t_offset: Time offset of the station relative to this host.
local_pm: local mesh STA power save mode
peer_pm: peer mesh STA power save mode
nonpeer_pm: non-peer mesh STA power save mode
expected_throughput: expected throughput in kbps (including 802.11 headers) towards this station.
rx_beacon: number of beacons received from this peer
rx_duration: aggregate PPDU duration(usecs) for all the frames from a peer
rx_beacon_signal_avg: signal strength average (in dBm) for beacons received from this peer
pertid: per-TID statistics, see struct cfg80211_tid_stats, using the last (IEEE80211_NUM_TIDS) index for MSDUs not encapsulated in QoS-MPDUs.

Description

Station information filled by driver for get_station() and dump_station.

enum monitor_flags¶: monitor flags

Constants

MONITOR_FLAG_CHANGED: set if the flags were changed
MONITOR_FLAG_FCSFAIL: pass frames with bad FCS
MONITOR_FLAG_PLCPFAIL: pass frames with bad PLCP
MONITOR_FLAG_CONTROL: pass control frames
MONITOR_FLAG_OTHER_BSS: disable BSSID filtering
MONITOR_FLAG_COOK_FRAMES: report frames after processing
MONITOR_FLAG_ACTIVE: active monitor, ACKs frames on its MAC address

Description

Monitor interface configuration flags. Note that these must be the bits according to the nl80211 flags.

enum mpath_info_flags¶: mesh path information flags

Constants

MPATH_INFO_FRAME_QLEN: frame_qlen filled
MPATH_INFO_SN: sn filled
MPATH_INFO_METRIC: metric filled
MPATH_INFO_EXPTIME: exptime filled
MPATH_INFO_DISCOVERY_TIMEOUT: discovery_timeout filled
MPATH_INFO_DISCOVERY_RETRIES: discovery_retries filled
MPATH_INFO_FLAGS: flags filled

Description

Used by the driver to indicate which info in struct mpath_info it has filled in during get_station() or dump_station().

struct mpath_info¶: mesh path information

Definition

struct mpath_info {
  u32 filled;
  u32 frame_qlen;
  u32 sn;
  u32 metric;
  u32 exptime;
  u32 discovery_timeout;
  u8 discovery_retries;
  u8 flags;
  int generation;
};

Members

filled: bitfield of flags from enum mpath_info_flags
frame_qlen: number of queued frames for this destination
sn: target sequence number
metric: metric (cost) of this mesh path
exptime: expiration time for the mesh path from now, in msecs
discovery_timeout: total mesh path discovery timeout, in msecs
discovery_retries: mesh path discovery retries
flags: mesh path flags
generation: generation number for nl80211 dumps. This number should increase every time the list of mesh paths changes, i.e. when a station is added or removed, so that userspace can tell whether it got a consistent snapshot.

Description

Mesh path information filled by driver for get_mpath() and dump_mpath().

struct bss_parameters¶: BSS parameters

Definition

struct bss_parameters {
  int use_cts_prot;
  int use_short_preamble;
  int use_short_slot_time;
  const u8 * basic_rates;
  u8 basic_rates_len;
  int ap_isolate;
  int ht_opmode;
  s8 p2p_ctwindow;
  s8 p2p_opp_ps;
};

Members

use_cts_prot: Whether to use CTS protection (0 = no, 1 = yes, -1 = do not change)
use_short_preamble: Whether the use of short preambles is allowed (0 = no, 1 = yes, -1 = do not change)
use_short_slot_time: Whether the use of short slot time is allowed (0 = no, 1 = yes, -1 = do not change)
basic_rates: basic rates in IEEE 802.11 format (or NULL for no change)
basic_rates_len: number of basic rates
ap_isolate: do not forward packets between connected stations
ht_opmode: HT Operation mode (u16 = opmode, -1 = do not change)
p2p_ctwindow: P2P CT Window (-1 = no change)
p2p_opp_ps: P2P opportunistic PS (-1 = no change)

Description

Used to change BSS parameters (mainly for AP mode).

struct ieee80211_txq_params¶: TX queue parameters

Definition

struct ieee80211_txq_params {
  enum nl80211_ac ac;
  u16 txop;
  u16 cwmin;
  u16 cwmax;
  u8 aifs;
};

Members

ac: AC identifier
txop: Maximum burst time in units of 32 usecs, 0 meaning disabled
cwmin: Minimum contention window [a value of the form 2^n-1 in the range 1..32767]
cwmax: Maximum contention window [a value of the form 2^n-1 in the range 1..32767]
aifs: Arbitration interframe space [0..255]

struct cfg80211_crypto_settings¶: Crypto settings

Definition

struct cfg80211_crypto_settings {
  u32 wpa_versions;
  u32 cipher_group;
  int n_ciphers_pairwise;
  u32 ciphers_pairwise;
  int n_akm_suites;
  u32 akm_suites;
  bool control_port;
  __be16 control_port_ethertype;
  bool control_port_no_encrypt;
  struct key_params * wep_keys;
  int wep_tx_key;
  const u8 * psk;
};

Members

wpa_versions: indicates which, if any, WPA versions are enabled (from enum nl80211_wpa_versions)
cipher_group: group key cipher suite (or 0 if unset)
n_ciphers_pairwise: number of AP supported unicast ciphers
ciphers_pairwise: unicast key cipher suites
n_akm_suites: number of AKM suites
akm_suites: AKM suites
control_port: Whether user space controls IEEE 802.1X port, i.e., sets/clears NL80211_STA_FLAG_AUTHORIZED. If true, the driver is required to assume that the port is unauthorized until authorized by user space. Otherwise, port is marked authorized by default.
control_port_ethertype: the control port protocol that should be allowed through even on unauthorized ports
control_port_no_encrypt: TRUE to prevent encryption of control port protocol frames.
wep_keys: static WEP keys, if not NULL points to an array of CFG80211_MAX_WEP_KEYS WEP keys
wep_tx_key: key index (0..3) of the default TX static WEP key
psk: PSK (for devices supporting 4-way-handshake offload)

struct cfg80211_auth_request¶: Authentication request data

Definition

struct cfg80211_auth_request {
  struct cfg80211_bss * bss;
  const u8 * ie;
  size_t ie_len;
  enum nl80211_auth_type auth_type;
  const u8 * key;
  u8 key_len;
  u8 key_idx;
  const u8 * auth_data;
  size_t auth_data_len;
};

Members

bss: The BSS to authenticate with, the callee must obtain a reference to it if it needs to keep it.
ie: Extra IEs to add to Authentication frame or NULL
ie_len: Length of ie buffer in octets
auth_type: Authentication type (algorithm)
key: WEP key for shared key authentication
key_len: length of WEP key for shared key authentication
key_idx: index of WEP key for shared key authentication
auth_data: Fields and elements in Authentication frames. This contains the authentication frame body (non-IE and IE data), excluding the Authentication algorithm number, i.e., starting at the Authentication transaction sequence number field.
auth_data_len: Length of auth_data buffer in octets

Description

This structure provides information needed to complete IEEE 802.11 authentication.

struct cfg80211_assoc_request¶: (Re)Association request data

Definition

struct cfg80211_assoc_request {
  struct cfg80211_bss * bss;
  const u8 * ie;
  const u8 * prev_bssid;
  size_t ie_len;
  struct cfg80211_crypto_settings crypto;
  bool use_mfp;
  u32 flags;
  struct ieee80211_ht_cap ht_capa;
  struct ieee80211_ht_cap ht_capa_mask;
  struct ieee80211_vht_cap vht_capa;
  struct ieee80211_vht_cap vht_capa_mask;
  const u8 * fils_kek;
  size_t fils_kek_len;
  const u8 * fils_nonces;
};

Members

bss: The BSS to associate with. If the call is successful the driver is given a reference that it must give back to cfg80211_send_rx_assoc() or to cfg80211_assoc_timeout(). To ensure proper refcounting, new association requests while already associating must be rejected.
ie: Extra IEs to add to (Re)Association Request frame or NULL
prev_bssid: previous BSSID, if not NULL use reassociate frame. This is used to indicate a request to reassociate within the ESS instead of a request do the initial association with the ESS. When included, this is set to the BSSID of the current association, i.e., to the value that is included in the Current AP address field of the Reassociation Request frame.
ie_len: Length of ie buffer in octets
crypto: crypto settings
use_mfp: Use management frame protection (IEEE 802.11w) in this association
flags: See enum cfg80211_assoc_req_flags
ht_capa: HT Capabilities over-rides. Values set in ht_capa_mask will be used in ht_capa. Un-supported values will be ignored.
ht_capa_mask: The bits of ht_capa which are to be used.
vht_capa: VHT capability override
vht_capa_mask: VHT capability mask indicating which fields to use
fils_kek: FILS KEK for protecting (Re)Association Request/Response frame or NULL if FILS is not used.
fils_kek_len: Length of fils_kek in octets
fils_nonces: FILS nonces (part of AAD) for protecting (Re)Association Request/Response frame or NULL if FILS is not used. This field starts with 16 octets of STA Nonce followed by 16 octets of AP Nonce.

Description

This structure provides information needed to complete IEEE 802.11 (re)association.

struct cfg80211_deauth_request¶: Deauthentication request data

Definition

struct cfg80211_deauth_request {
  const u8 * bssid;
  const u8 * ie;
  size_t ie_len;
  u16 reason_code;
  bool local_state_change;
};

Members

bssid: the BSSID of the BSS to deauthenticate from
ie: Extra IEs to add to Deauthentication frame or NULL
ie_len: Length of ie buffer in octets
reason_code: The reason code for the deauthentication
local_state_change: if set, change local state only and do not set a deauth frame

Description

This structure provides information needed to complete IEEE 802.11 deauthentication.

struct cfg80211_disassoc_request¶: Disassociation request data

Definition

struct cfg80211_disassoc_request {
  struct cfg80211_bss * bss;
  const u8 * ie;
  size_t ie_len;
  u16 reason_code;
  bool local_state_change;
};

Members

bss: the BSS to disassociate from
ie: Extra IEs to add to Disassociation frame or NULL
ie_len: Length of ie buffer in octets
reason_code: The reason code for the disassociation
local_state_change: This is a request for a local state only, i.e., no Disassociation frame is to be transmitted.

Description

This structure provides information needed to complete IEEE 802.11 disassociation.

struct cfg80211_ibss_params¶: IBSS parameters

Definition

struct cfg80211_ibss_params {
  const u8 * ssid;
  const u8 * bssid;
  struct cfg80211_chan_def chandef;
  const u8 * ie;
  u8 ssid_len;
  u8 ie_len;
  u16 beacon_interval;
  u32 basic_rates;
  bool channel_fixed;
  bool privacy;
  bool control_port;
  bool userspace_handles_dfs;
  int mcast_rate;
  struct ieee80211_ht_cap ht_capa;
  struct ieee80211_ht_cap ht_capa_mask;
};

Members

ssid: The SSID, will always be non-null.
bssid: Fixed BSSID requested, maybe be NULL, if set do not search for IBSSs with a different BSSID.
chandef: defines the channel to use if no other IBSS to join can be found
ie: information element(s) to include in the beacon
ssid_len: The length of the SSID, will always be non-zero.
ie_len: length of that
beacon_interval: beacon interval to use
basic_rates: bitmap of basic rates to use when creating the IBSS
channel_fixed: The channel should be fixed – do not search for IBSSs to join on other channels.
privacy: this is a protected network, keys will be configured after joining
control_port: whether user space controls IEEE 802.1X port, i.e., sets/clears NL80211_STA_FLAG_AUTHORIZED. If true, the driver is required to assume that the port is unauthorized until authorized by user space. Otherwise, port is marked authorized by default.
userspace_handles_dfs: whether user space controls DFS operation, i.e. changes the channel when a radar is detected. This is required to operate on DFS channels.
mcast_rate: per-band multicast rate index + 1 (0: disabled)
ht_capa: HT Capabilities over-rides. Values set in ht_capa_mask will be used in ht_capa. Un-supported values will be ignored.
ht_capa_mask: The bits of ht_capa which are to be used.

Description

This structure defines the IBSS parameters for the join_ibss() method.

struct cfg80211_connect_params¶: Connection parameters

Definition

struct cfg80211_connect_params {
  struct ieee80211_channel * channel;
  struct ieee80211_channel * channel_hint;
  const u8 * bssid;
  const u8 * bssid_hint;
  const u8 * ssid;
  size_t ssid_len;
  enum nl80211_auth_type auth_type;
  const u8 * ie;
  size_t ie_len;
  bool privacy;
  enum nl80211_mfp mfp;
  struct cfg80211_crypto_settings crypto;
  const u8 * key;
  u8 key_len;
  u8 key_idx;
  u32 flags;
  int bg_scan_period;
  struct ieee80211_ht_cap ht_capa;
  struct ieee80211_ht_cap ht_capa_mask;
  struct ieee80211_vht_cap vht_capa;
  struct ieee80211_vht_cap vht_capa_mask;
  bool pbss;
  struct cfg80211_bss_selection bss_select;
  const u8 * prev_bssid;
  const u8 * fils_erp_username;
  size_t fils_erp_username_len;
  const u8 * fils_erp_realm;
  size_t fils_erp_realm_len;
  u16 fils_erp_next_seq_num;
  const u8 * fils_erp_rrk;
  size_t fils_erp_rrk_len;
  bool want_1x;
};

Members

channel: The channel to use or NULL if not specified (auto-select based on scan results)
channel_hint: The channel of the recommended BSS for initial connection or NULL if not specified
bssid: The AP BSSID or NULL if not specified (auto-select based on scan results)
bssid_hint: The recommended AP BSSID for initial connection to the BSS or NULL if not specified. Unlike the bssid parameter, the driver is allowed to ignore this bssid_hint if it has knowledge of a better BSS to use.
ssid: SSID
ssid_len: Length of ssid in octets
auth_type: Authentication type (algorithm)
ie: IEs for association request
ie_len: Length of assoc_ie in octets
privacy: indicates whether privacy-enabled APs should be used
mfp: indicate whether management frame protection is used
crypto: crypto settings
key: WEP key for shared key authentication
key_len: length of WEP key for shared key authentication
key_idx: index of WEP key for shared key authentication
flags: See enum cfg80211_assoc_req_flags
bg_scan_period: Background scan period in seconds or -1 to indicate that default value is to be used.
ht_capa: HT Capabilities over-rides. Values set in ht_capa_mask will be used in ht_capa. Un-supported values will be ignored.
ht_capa_mask: The bits of ht_capa which are to be used.
vht_capa: VHT Capability overrides
vht_capa_mask: The bits of vht_capa which are to be used.
pbss: if set, connect to a PCP instead of AP. Valid for DMG networks.
bss_select: criteria to be used for BSS selection.
prev_bssid: previous BSSID, if not NULL use reassociate frame. This is used to indicate a request to reassociate within the ESS instead of a request do the initial association with the ESS. When included, this is set to the BSSID of the current association, i.e., to the value that is included in the Current AP address field of the Reassociation Request frame.
fils_erp_username: EAP re-authentication protocol (ERP) username part of the NAI or NULL if not specified. This is used to construct FILS wrapped data IE.
fils_erp_username_len: Length of fils_erp_username in octets.
fils_erp_realm: EAP re-authentication protocol (ERP) realm part of NAI or NULL if not specified. This specifies the domain name of ER server and is used to construct FILS wrapped data IE.
fils_erp_realm_len: Length of fils_erp_realm in octets.
fils_erp_next_seq_num: The next sequence number to use in the FILS ERP messages. This is also used to construct FILS wrapped data IE.
fils_erp_rrk: ERP re-authentication Root Key (rRK) used to derive additional keys in FILS or NULL if not specified.
fils_erp_rrk_len: Length of fils_erp_rrk in octets.
want_1x: indicates user-space supports and wants to use 802.1X driver offload of 4-way handshake.

Description

This structure provides information needed to complete IEEE 802.11 authentication and association.

struct cfg80211_pmksa¶: PMK Security Association

Definition

struct cfg80211_pmksa {
  const u8 * bssid;
  const u8 * pmkid;
  const u8 * pmk;
  size_t pmk_len;
  const u8 * ssid;
  size_t ssid_len;
  const u8 * cache_id;
};

Members

bssid: The AP’s BSSID (may be NULL).
pmkid: The identifier to refer a PMKSA.
pmk: The PMK for the PMKSA identified by pmkid. This is used for key derivation by a FILS STA. Otherwise, NULL.
pmk_len: Length of the pmk. The length of pmk can differ depending on the hash algorithm used to generate this.
ssid: SSID to specify the ESS within which a PMKSA is valid when using FILS cache identifier (may be NULL).
ssid_len: Length of the ssid in octets.
cache_id: 2-octet cache identifier advertized by a FILS AP identifying the scope of PMKSA. This is valid only if ssid_len is non-zero (may be NULL).

Description

This structure is passed to the set/del_pmksa() method for PMKSA caching.

void cfg80211_rx_mlme_mgmt(struct net_device * dev, const u8 * buf, size_t len)¶: notification of processed MLME management frame

Parameters

struct net_device * dev: network device
const u8 * buf: authentication frame (header + body)
size_t len: length of the frame data

Description

This function is called whenever an authentication, disassociation or deauthentication frame has been received and processed in station mode. After being asked to authenticate via cfg80211_ops::auth() the driver must call either this function or cfg80211_auth_timeout(). After being asked to associate via cfg80211_ops::assoc() the driver must call either this function or cfg80211_auth_timeout(). While connected, the driver must calls this for received and processed disassociation and deauthentication frames. If the frame couldn’t be used because it was unprotected, the driver must call the function cfg80211_rx_unprot_mlme_mgmt() instead.

This function may sleep. The caller must hold the corresponding wdev’s mutex.

void cfg80211_auth_timeout(struct net_device * dev, const u8 * addr)¶: notification of timed out authentication

Parameters

struct net_device * dev: network device
const u8 * addr: The MAC address of the device with which the authentication timed out

Description

This function may sleep. The caller must hold the corresponding wdev’s mutex.

void cfg80211_rx_assoc_resp(struct net_device * dev, struct cfg80211_bss * bss, const u8 * buf, size_t len, int uapsd_queues)¶: notification of processed association response

Parameters

struct net_device * dev: network device
struct cfg80211_bss * bss: the BSS that association was requested with, ownership of the pointer moves to cfg80211 in this call
const u8 * buf: authentication frame (header + body)
size_t len: length of the frame data
int uapsd_queues: bitmap of queues configured for uapsd. Same format as the AC bitmap in the QoS info field

Description

After being asked to associate via cfg80211_ops::assoc() the driver must call either this function or cfg80211_auth_timeout().

This function may sleep. The caller must hold the corresponding wdev’s mutex.

void cfg80211_assoc_timeout(struct net_device * dev, struct cfg80211_bss * bss)¶: notification of timed out association

Parameters

struct net_device * dev: network device
struct cfg80211_bss * bss: The BSS entry with which association timed out.

Description

This function may sleep. The caller must hold the corresponding wdev’s mutex.

void cfg80211_tx_mlme_mgmt(struct net_device * dev, const u8 * buf, size_t len)¶: notification of transmitted deauth/disassoc frame

Parameters

struct net_device * dev: network device
const u8 * buf: 802.11 frame (header + body)
size_t len: length of the frame data

Description

This function is called whenever deauthentication has been processed in station mode. This includes both received deauthentication frames and locally generated ones. This function may sleep. The caller must hold the corresponding wdev’s mutex.

void cfg80211_ibss_joined(struct net_device * dev, const u8 * bssid, struct ieee80211_channel * channel, gfp_t gfp)¶: notify cfg80211 that device joined an IBSS

Parameters

struct net_device * dev: network device
const u8 * bssid: the BSSID of the IBSS joined
struct ieee80211_channel * channel: the channel of the IBSS joined
gfp_t gfp: allocation flags

Description

This function notifies cfg80211 that the device joined an IBSS or switched to a different BSSID. Before this function can be called, either a beacon has to have been received from the IBSS, or one of the cfg80211_inform_bss{,_frame} functions must have been called with the locally generated beacon – this guarantees that there is always a scan result for this IBSS. cfg80211 will handle the rest.

struct cfg80211_connect_resp_params¶: Connection response params

Definition

struct cfg80211_connect_resp_params {
  int status;
  const u8 * bssid;
  struct cfg80211_bss * bss;
  const u8 * req_ie;
  size_t req_ie_len;
  const u8 * resp_ie;
  size_t resp_ie_len;
  const u8 * fils_kek;
  size_t fils_kek_len;
  bool update_erp_next_seq_num;
  u16 fils_erp_next_seq_num;
  const u8 * pmk;
  size_t pmk_len;
  const u8 * pmkid;
  enum nl80211_timeout_reason timeout_reason;
};

Members

status: Status code, WLAN_STATUS_SUCCESS for successful connection, use WLAN_STATUS_UNSPECIFIED_FAILURE if your device cannot give you the real status code for failures. If this call is used to report a failure due to a timeout (e.g., not receiving an Authentication frame from the AP) instead of an explicit rejection by the AP, -1 is used to indicate that this is a failure, but without a status code. timeout_reason is used to report the reason for the timeout in that case.
bssid: The BSSID of the AP (may be NULL)
bss: Entry of bss to which STA got connected to, can be obtained through cfg80211_get_bss() (may be NULL). Only one parameter among bssid and bss needs to be specified.
req_ie: Association request IEs (may be NULL)
req_ie_len: Association request IEs length
resp_ie: Association response IEs (may be NULL)
resp_ie_len: Association response IEs length
fils_kek: KEK derived from a successful FILS connection (may be NULL)
fils_kek_len: Length of fils_kek in octets
update_erp_next_seq_num: Boolean value to specify whether the value in fils_erp_next_seq_num is valid.
fils_erp_next_seq_num: The next sequence number to use in ERP message in FILS Authentication. This value should be specified irrespective of the status for a FILS connection.
pmk: A new PMK if derived from a successful FILS connection (may be NULL).
pmk_len: Length of pmk in octets
pmkid: A new PMKID if derived from a successful FILS connection or the PMKID used for this FILS connection (may be NULL).
timeout_reason: Reason for connection timeout. This is used when the connection fails due to a timeout instead of an explicit rejection from the AP. NL80211_TIMEOUT_UNSPECIFIED is used when the timeout reason is not known. This value is used only if status < 0 to indicate that the failure is due to a timeout and not due to explicit rejection by the AP. This value is ignored in other cases (status >= 0).

void cfg80211_connect_done(struct net_device * dev, struct cfg80211_connect_resp_params * params, gfp_t gfp)¶: notify cfg80211 of connection result

Parameters

struct net_device * dev: network device
struct cfg80211_connect_resp_params * params: connection response parameters
gfp_t gfp: allocation flags

Description

It should be called by the underlying driver once execution of the connection request from connect() has been completed. This is similar to cfg80211_connect_bss(), but takes a structure pointer for connection response parameters. Only one of the functions among cfg80211_connect_bss(), cfg80211_connect_result(), cfg80211_connect_timeout(), and cfg80211_connect_done() should be called.

void cfg80211_connect_result(struct net_device * dev, const u8 * bssid, const u8 * req_ie, size_t req_ie_len, const u8 * resp_ie, size_t resp_ie_len, u16 status, gfp_t gfp)¶: notify cfg80211 of connection result

Parameters

struct net_device * dev: network device
const u8 * bssid: the BSSID of the AP
const u8 * req_ie: association request IEs (maybe be NULL)
size_t req_ie_len: association request IEs length
const u8 * resp_ie: association response IEs (may be NULL)
size_t resp_ie_len: assoc response IEs length
u16 status: status code, WLAN_STATUS_SUCCESS for successful connection, use WLAN_STATUS_UNSPECIFIED_FAILURE if your device cannot give you the real status code for failures.
gfp_t gfp: allocation flags

Description

It should be called by the underlying driver once execution of the connection request from connect() has been completed. This is similar to cfg80211_connect_bss() which allows the exact bss entry to be specified. Only one of the functions among cfg80211_connect_bss(), cfg80211_connect_result(), cfg80211_connect_timeout(), and cfg80211_connect_done() should be called.

void cfg80211_connect_bss(struct net_device * dev, const u8 * bssid, struct cfg80211_bss * bss, const u8 * req_ie, size_t req_ie_len, const u8 * resp_ie, size_t resp_ie_len, int status, gfp_t gfp, enum nl80211_timeout_reason timeout_reason)¶: notify cfg80211 of connection result

Parameters

struct net_device * dev: network device
const u8 * bssid: the BSSID of the AP
struct cfg80211_bss * bss: entry of bss to which STA got connected to, can be obtained through cfg80211_get_bss (may be NULL)
const u8 * req_ie: association request IEs (maybe be NULL)
size_t req_ie_len: association request IEs length
const u8 * resp_ie: association response IEs (may be NULL)
size_t resp_ie_len: assoc response IEs length
int status: status code, WLAN_STATUS_SUCCESS for successful connection, use WLAN_STATUS_UNSPECIFIED_FAILURE if your device cannot give you the real status code for failures. If this call is used to report a failure due to a timeout (e.g., not receiving an Authentication frame from the AP) instead of an explicit rejection by the AP, -1 is used to indicate that this is a failure, but without a status code. timeout_reason is used to report the reason for the timeout in that case.
gfp_t gfp: allocation flags
enum nl80211_timeout_reason timeout_reason: reason for connection timeout. This is used when the connection fails due to a timeout instead of an explicit rejection from the AP. NL80211_TIMEOUT_UNSPECIFIED is used when the timeout reason is not known. This value is used only if status < 0 to indicate that the failure is due to a timeout and not due to explicit rejection by the AP. This value is ignored in other cases (status >= 0).

Description

It should be called by the underlying driver once execution of the connection request from connect() has been completed. This is similar to cfg80211_connect_result(), but with the option of identifying the exact bss entry for the connection. Only one of the functions among cfg80211_connect_bss(), cfg80211_connect_result(), cfg80211_connect_timeout(), and cfg80211_connect_done() should be called.

void cfg80211_connect_timeout(struct net_device * dev, const u8 * bssid, const u8 * req_ie, size_t req_ie_len, gfp_t gfp, enum nl80211_timeout_reason timeout_reason)¶: notify cfg80211 of connection timeout

Parameters

struct net_device * dev: network device
const u8 * bssid: the BSSID of the AP
const u8 * req_ie: association request IEs (maybe be NULL)
size_t req_ie_len: association request IEs length
gfp_t gfp: allocation flags
enum nl80211_timeout_reason timeout_reason: reason for connection timeout.

Description

It should be called by the underlying driver whenever connect() has failed in a sequence where no explicit authentication/association rejection was received from the AP. This could happen, e.g., due to not being able to send out the Authentication or Association Request frame or timing out while waiting for the response. Only one of the functions among cfg80211_connect_bss(), cfg80211_connect_result(), cfg80211_connect_timeout(), and cfg80211_connect_done() should be called.

void cfg80211_roamed(struct net_device * dev, struct cfg80211_roam_info * info, gfp_t gfp)¶: notify cfg80211 of roaming

Parameters

struct net_device * dev: network device
struct cfg80211_roam_info * info: information about the new BSS. struct cfg80211_roam_info.
gfp_t gfp: allocation flags

Description

This function may be called with the driver passing either the BSSID of the new AP or passing the bss entry to avoid a race in timeout of the bss entry. It should be called by the underlying driver whenever it roamed from one AP to another while connected. Drivers which have roaming implemented in firmware should pass the bss entry to avoid a race in bss entry timeout where the bss entry of the new AP is seen in the driver, but gets timed out by the time it is accessed in __cfg80211_roamed() due to delay in scheduling rdev->event_work. In case of any failures, the reference is released either in cfg80211_roamed() or in __cfg80211_romed(), Otherwise, it will be released while diconneting from the current bss.

void cfg80211_disconnected(struct net_device * dev, u16 reason, const u8 * ie, size_t ie_len, bool locally_generated, gfp_t gfp)¶: notify cfg80211 that connection was dropped

Parameters

struct net_device * dev: network device
u16 reason: reason code for the disconnection, set it to 0 if unknown
const u8 * ie: information elements of the deauth/disassoc frame (may be NULL)
size_t ie_len: length of IEs
bool locally_generated: disconnection was requested locally
gfp_t gfp: allocation flags

Description

After it calls this function, the driver should enter an idle state and not try to connect to any AP any more.

void cfg80211_ready_on_channel(struct wireless_dev * wdev, u64 cookie, struct ieee80211_channel * chan, unsigned int duration, gfp_t gfp)¶: notification of remain_on_channel start

Parameters

struct wireless_dev * wdev: wireless device
u64 cookie: the request cookie
struct ieee80211_channel * chan: The current channel (from remain_on_channel request)
unsigned int duration: Duration in milliseconds that the driver intents to remain on the channel
gfp_t gfp: allocation flags

void cfg80211_remain_on_channel_expired(struct wireless_dev * wdev, u64 cookie, struct ieee80211_channel * chan, gfp_t gfp)¶: remain_on_channel duration expired

Parameters

struct wireless_dev * wdev: wireless device
u64 cookie: the request cookie
struct ieee80211_channel * chan: The current channel (from remain_on_channel request)
gfp_t gfp: allocation flags

void cfg80211_new_sta(struct net_device * dev, const u8 * mac_addr, struct station_info * sinfo, gfp_t gfp)¶: notify userspace about station

Parameters

struct net_device * dev: the netdev
const u8 * mac_addr: the station’s address
struct station_info * sinfo: the station information
gfp_t gfp: allocation flags

bool cfg80211_rx_mgmt(struct wireless_dev * wdev, int freq, int sig_dbm, const u8 * buf, size_t len, u32 flags)¶: notification of received, unprocessed management frame

Parameters

struct wireless_dev * wdev: wireless device receiving the frame
int freq: Frequency on which the frame was received in MHz
int sig_dbm: signal strength in mBm, or 0 if unknown
const u8 * buf: Management frame (header + body)
size_t len: length of the frame data
u32 flags: flags, as defined in enum nl80211_rxmgmt_flags

Description

This function is called whenever an Action frame is received for a station mode interface, but is not processed in kernel.

Return

true if a user space application has registered for this frame. For action frames, that makes it responsible for rejecting unrecognized action frames; false otherwise, in which case for action frames the driver is responsible for rejecting the frame.

void cfg80211_mgmt_tx_status(struct wireless_dev * wdev, u64 cookie, const u8 * buf, size_t len, bool ack, gfp_t gfp)¶: notification of TX status for management frame

Parameters

struct wireless_dev * wdev: wireless device receiving the frame
u64 cookie: Cookie returned by cfg80211_ops::mgmt_tx()
const u8 * buf: Management frame (header + body)
size_t len: length of the frame data
bool ack: Whether frame was acknowledged
gfp_t gfp: context flags

Description

This function is called whenever a management frame was requested to be transmitted with cfg80211_ops::mgmt_tx() to report the TX status of the transmission attempt.

void cfg80211_cqm_rssi_notify(struct net_device * dev, enum nl80211_cqm_rssi_threshold_event rssi_event, s32 rssi_level, gfp_t gfp)¶: connection quality monitoring rssi event

Parameters

struct net_device * dev: network device
enum nl80211_cqm_rssi_threshold_event rssi_event: the triggered RSSI event
s32 rssi_level: new RSSI level value or 0 if not available
gfp_t gfp: context flags

Description

This function is called when a configured connection quality monitoring rssi threshold reached event occurs.

void cfg80211_cqm_pktloss_notify(struct net_device * dev, const u8 * peer, u32 num_packets, gfp_t gfp)¶: notify userspace about packetloss to peer

Parameters

struct net_device * dev: network device
const u8 * peer: peer’s MAC address
u32 num_packets: how many packets were lost – should be a fixed threshold but probably no less than maybe 50, or maybe a throughput dependent threshold (to account for temporary interference)
gfp_t gfp: context flags

void cfg80211_michael_mic_failure(struct net_device * dev, const u8 * addr, enum nl80211_key_type key_type, int key_id, const u8 * tsc, gfp_t gfp)¶: notification of Michael MIC failure (TKIP)

Parameters

struct net_device * dev: network device
const u8 * addr: The source MAC address of the frame
enum nl80211_key_type key_type: The key type that the received frame used
int key_id: Key identifier (0..3). Can be -1 if missing.
const u8 * tsc: The TSC value of the frame that generated the MIC failure (6 octets)
gfp_t gfp: allocation flags

Description

This function is called whenever the local MAC detects a MIC failure in a received frame. This matches with MLME-MICHAELMICFAILURE.:c:func:indication() primitive.

Scanning and BSS list handling¶

The scanning process itself is fairly simple, but cfg80211 offers quite a bit of helper functionality. To start a scan, the scan operation will be invoked with a scan definition. This scan definition contains the channels to scan, and the SSIDs to send probe requests for (including the wildcard, if desired). A passive scan is indicated by having no SSIDs to probe. Additionally, a scan request may contain extra information elements that should be added to the probe request. The IEs are guaranteed to be well-formed, and will not exceed the maximum length the driver advertised in the wiphy structure.

When scanning finds a BSS, cfg80211 needs to be notified of that, because it is responsible for maintaining the BSS list; the driver should not maintain a list itself. For this notification, various functions exist.

Since drivers do not maintain a BSS list, there are also a number of functions to search for a BSS and obtain information about it from the BSS structure cfg80211 maintains. The BSS list is also made available to userspace.

struct cfg80211_ssid¶: SSID description

Definition

struct cfg80211_ssid {
  u8 ssid;
  u8 ssid_len;
};

Members

ssid: the SSID
ssid_len: length of the ssid

struct cfg80211_scan_request¶: scan request description

Definition

struct cfg80211_scan_request {
  struct cfg80211_ssid * ssids;
  int n_ssids;
  u32 n_channels;
  enum nl80211_bss_scan_width scan_width;
  const u8 * ie;
  size_t ie_len;
  u16 duration;
  bool duration_mandatory;
  u32 flags;
  u32 rates;
  struct wireless_dev * wdev;
  u8 mac_addr;
  u8 mac_addr_mask;
  u8 bssid;
  struct wiphy * wiphy;
  unsigned long scan_start;
  struct cfg80211_scan_info info;
  bool notified;
  bool no_cck;
  struct ieee80211_channel * channels;
};

Members

ssids: SSIDs to scan for (active scan only)
n_ssids: number of SSIDs
n_channels: total number of channels to scan
scan_width: channel width for scanning
ie: optional information element(s) to add into Probe Request or NULL
ie_len: length of ie in octets
duration: how long to listen on each channel, in TUs. If duration_mandatory is not set, this is the maximum dwell time and the actual dwell time may be shorter.
duration_mandatory: if set, the scan duration must be as specified by the duration field.
flags: bit field of flags controlling operation
rates: bitmap of rates to advertise for each band
wdev: the wireless device to scan for
mac_addr: MAC address used with randomisation
mac_addr_mask: MAC address mask used with randomisation, bits that are 0 in the mask should be randomised, bits that are 1 should be taken from the mac_addr
bssid: BSSID to scan for (most commonly, the wildcard BSSID)
wiphy: the wiphy this was for
scan_start: time (in jiffies) when the scan started
info: (internal) information about completed scan
notified: (internal) scan request was notified as done or aborted
no_cck: used to send probe requests at non CCK rate in 2GHz band
channels: channels to scan on.

void cfg80211_scan_done(struct cfg80211_scan_request * request, struct cfg80211_scan_info * info)¶: notify that scan finished

Parameters

struct cfg80211_scan_request * request: the corresponding scan request
struct cfg80211_scan_info * info: information about the completed scan

struct cfg80211_bss¶: BSS description

Definition

struct cfg80211_bss {
  struct ieee80211_channel * channel;
  enum nl80211_bss_scan_width scan_width;
  const struct cfg80211_bss_ies __rcu * ies;
  const struct cfg80211_bss_ies __rcu * beacon_ies;
  const struct cfg80211_bss_ies __rcu * proberesp_ies;
  struct cfg80211_bss * hidden_beacon_bss;
  s32 signal;
  u16 beacon_interval;
  u16 capability;
  u8 bssid;
  u8 priv;
};

Members

channel: channel this BSS is on
scan_width: width of the control channel
ies: the information elements (Note that there is no guarantee that these are well-formed!); this is a pointer to either the beacon_ies or proberesp_ies depending on whether Probe Response frame has been received. It is always non-NULL.
beacon_ies: the information elements from the last Beacon frame (implementation note: if hidden_beacon_bss is set this struct doesn’t own the beacon_ies, but they’re just pointers to the ones from the hidden_beacon_bss struct)
proberesp_ies: the information elements from the last Probe Response frame
hidden_beacon_bss: in case this BSS struct represents a probe response from a BSS that hides the SSID in its beacon, this points to the BSS struct that holds the beacon data. beacon_ies is still valid, of course, and points to the same data as hidden_beacon_bss->beacon_ies in that case.
signal: signal strength value (type depends on the wiphy’s signal_type)
beacon_interval: the beacon interval as from the frame
capability: the capability field in host byte order
bssid: BSSID of the BSS
priv: private area for driver use, has at least wiphy->bss_priv_size bytes

Description

This structure describes a BSS (which may also be a mesh network) for use in scan results and similar.

struct cfg80211_inform_bss¶: BSS inform data

Definition

struct cfg80211_inform_bss {
  struct ieee80211_channel * chan;
  enum nl80211_bss_scan_width scan_width;
  s32 signal;
  u64 boottime_ns;
  u64 parent_tsf;
  u8 parent_bssid;
};

Members

chan: channel the frame was received on
scan_width: scan width that was used
signal: signal strength value, according to the wiphy’s signal type
boottime_ns: timestamp (CLOCK_BOOTTIME) when the information was received; should match the time when the frame was actually received by the device (not just by the host, in case it was buffered on the device) and be accurate to about 10ms. If the frame isn’t buffered, just passing the return value of ktime_get_boot_ns() is likely appropriate.
parent_tsf: the time at the start of reception of the first octet of the timestamp field of the frame. The time is the TSF of the BSS specified by parent_bssid.
parent_bssid: the BSS according to which parent_tsf is set. This is set to the BSS that requested the scan in which the beacon/probe was received.

struct cfg80211_bss * cfg80211_inform_bss_frame_data(struct wiphy * wiphy, struct cfg80211_inform_bss * data, struct ieee80211_mgmt * mgmt, size_t len, gfp_t gfp)¶: inform cfg80211 of a received BSS frame

Parameters

struct wiphy * wiphy: the wiphy reporting the BSS
struct cfg80211_inform_bss * data: the BSS metadata
struct ieee80211_mgmt * mgmt: the management frame (probe response or beacon)
size_t len: length of the management frame
gfp_t gfp: context flags

Description

This informs cfg80211 that BSS information was found and the BSS should be updated/added.

Return

A referenced struct, must be released with cfg80211_put_bss()! Or NULL on error.

struct cfg80211_bss * cfg80211_inform_bss_data(struct wiphy * wiphy, struct cfg80211_inform_bss * data, enum cfg80211_bss_frame_type ftype, const u8 * bssid, u64 tsf, u16 capability, u16 beacon_interval, const u8 * ie, size_t ielen, gfp_t gfp)¶: inform cfg80211 of a new BSS

Parameters

struct wiphy * wiphy: the wiphy reporting the BSS
struct cfg80211_inform_bss * data: the BSS metadata
enum cfg80211_bss_frame_type ftype: frame type (if known)
const u8 * bssid: the BSSID of the BSS
u64 tsf: the TSF sent by the peer in the beacon/probe response (or 0)
u16 capability: the capability field sent by the peer
u16 beacon_interval: the beacon interval announced by the peer
const u8 * ie: additional IEs sent by the peer
size_t ielen: length of the additional IEs
gfp_t gfp: context flags

Description

This informs cfg80211 that BSS information was found and the BSS should be updated/added.

Return

A referenced struct, must be released with cfg80211_put_bss()! Or NULL on error.

void cfg80211_unlink_bss(struct wiphy * wiphy, struct cfg80211_bss * bss)¶: unlink BSS from internal data structures

Parameters

struct wiphy * wiphy: the wiphy
struct cfg80211_bss * bss: the bss to remove

Description

This function removes the given BSS from the internal data structures thereby making it no longer show up in scan results etc. Use this function when you detect a BSS is gone. Normally BSSes will also time out, so it is not necessary to use this function at all.

const u8 * cfg80211_find_ie(u8 eid, const u8 * ies, int len)¶: find information element in data

Parameters

u8 eid: element ID
const u8 * ies: data consisting of IEs
int len: length of data

Return

NULL if the element ID could not be found or if the element is invalid (claims to be longer than the given data), or a pointer to the first byte of the requested element, that is the byte containing the element ID.

Note

There are no checks on the element length other than having to fit into the given data.

const u8 * ieee80211_bss_get_ie(struct cfg80211_bss * bss, u8 ie)¶: find IE with given ID

Parameters

struct cfg80211_bss * bss: the bss to search
u8 ie: the IE ID

Description

Note that the return value is an RCU-protected pointer, so rcu_read_lock() must be held when calling this function.

Return

NULL if not found.

Utility functions¶

cfg80211 offers a number of utility functions that can be useful.

int ieee80211_channel_to_frequency(int chan, enum nl80211_band band)¶: convert channel number to frequency

Parameters

int chan: channel number
enum nl80211_band band: band, necessary due to channel number overlap

Return

The corresponding frequency (in MHz), or 0 if the conversion failed.

int ieee80211_frequency_to_channel(int freq)¶: convert frequency to channel number

Parameters

int freq: center frequency

Return

The corresponding channel, or 0 if the conversion failed.

struct ieee80211_channel * ieee80211_get_channel(struct wiphy * wiphy, int freq)¶: get channel struct from wiphy for specified frequency

Parameters

struct wiphy * wiphy: the struct wiphy to get the channel for
int freq: the center frequency of the channel

Return

The channel struct from wiphy at freq.

struct ieee80211_rate * ieee80211_get_response_rate(struct ieee80211_supported_band * sband, u32 basic_rates, int bitrate)¶: get basic rate for a given rate

Parameters

struct ieee80211_supported_band * sband: the band to look for rates in
u32 basic_rates: bitmap of basic rates
int bitrate: the bitrate for which to find the basic rate

Return

The basic rate corresponding to a given bitrate, that is the next lower bitrate contained in the basic rate map, which is, for this function, given as a bitmap of indices of rates in the band’s bitrate table.

unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)¶: get header length in bytes from frame control

Parameters

__le16 fc: frame control field in little-endian format

Return

The header length in bytes.

unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff * skb)¶: get header length from data

Parameters

const struct sk_buff * skb: the frame

Description

Given an skb with a raw 802.11 header at the data pointer this function returns the 802.11 header length.

Return

The 802.11 header length in bytes (not including encryption headers). Or 0 if the data in the sk_buff is too short to contain a valid 802.11 header.

struct ieee80211_radiotap_iterator¶: tracks walk thru present radiotap args

Definition

struct ieee80211_radiotap_iterator {
  struct ieee80211_radiotap_header * _rtheader;
  const struct ieee80211_radiotap_vendor_namespaces * _vns;
  const struct ieee80211_radiotap_namespace * current_namespace;
  unsigned char * _arg;
  unsigned char * _next_ns_data;
  __le32 * _next_bitmap;
  unsigned char * this_arg;
  int this_arg_index;
  int this_arg_size;
  int is_radiotap_ns;
  int _max_length;
  int _arg_index;
  uint32_t _bitmap_shifter;
  int _reset_on_ext;
};

Members

_rtheader: pointer to the radiotap header we are walking through
_vns: vendor namespace definitions
current_namespace: pointer to the current namespace definition (or internally NULL if the current namespace is unknown)
_arg: next argument pointer
_next_ns_data: beginning of the next namespace’s data
_next_bitmap: internal pointer to next present u32
this_arg: pointer to current radiotap arg; it is valid after each call to ieee80211_radiotap_iterator_next() but also after ieee80211_radiotap_iterator_init() where it will point to the beginning of the actual data portion
this_arg_index: index of current arg, valid after each successful call to ieee80211_radiotap_iterator_next()
this_arg_size: length of the current arg, for convenience
is_radiotap_ns: indicates whether the current namespace is the default radiotap namespace or not
_max_length: length of radiotap header in cpu byte ordering
_arg_index: next argument index
_bitmap_shifter: internal shifter for curr u32 bitmap, b0 set == arg present
_reset_on_ext: internal; reset the arg index to 0 when going to the next bitmap word

Description

Describes the radiotap parser state. Fields prefixed with an underscore must not be used by users of the parser, only by the parser internally.

Data path helpers¶

In addition to generic utilities, cfg80211 also offers functions that help implement the data path for devices that do not do the 802.11/802.3 conversion on the device.

int ieee80211_data_to_8023(struct sk_buff * skb, const u8 * addr, enum nl80211_iftype iftype)¶: convert an 802.11 data frame to 802.3

Parameters

struct sk_buff * skb: the 802.11 data frame
const u8 * addr: the device MAC address
enum nl80211_iftype iftype: the virtual interface type

Return

0 on success. Non-zero on error.

int ieee80211_data_from_8023(struct sk_buff * skb, const u8 * addr, enum nl80211_iftype iftype, const u8 * bssid, bool qos)¶: convert an 802.3 frame to 802.11

Parameters

struct sk_buff * skb: the 802.3 frame
const u8 * addr: the device MAC address
enum nl80211_iftype iftype: the virtual interface type
const u8 * bssid: the network bssid (used only for iftype STATION and ADHOC)
bool qos: build 802.11 QoS data frame

Return

0 on success, or a negative error code.

void ieee80211_amsdu_to_8023s(struct sk_buff * skb, struct sk_buff_head * list, const u8 * addr, enum nl80211_iftype iftype, const unsigned int extra_headroom, const u8 * check_da, const u8 * check_sa)¶: decode an IEEE 802.11n A-MSDU frame

Parameters

struct sk_buff * skb: The input A-MSDU frame without any headers.
struct sk_buff_head * list: The output list of 802.3 frames. It must be allocated and initialized by by the caller.
const u8 * addr: The device MAC address.
enum nl80211_iftype iftype: The device interface type.
const unsigned int extra_headroom: The hardware extra headroom for SKBs in the list.
const u8 * check_da: DA to check in the inner ethernet header, or NULL
const u8 * check_sa: SA to check in the inner ethernet header, or NULL

Description

Decode an IEEE 802.11 A-MSDU and convert it to a list of 802.3 frames. The list will be empty if the decode fails. The skb must be fully header-less before being passed in here; it is freed in this function.

unsigned int cfg80211_classify8021d(struct sk_buff * skb, struct cfg80211_qos_map * qos_map)¶: determine the 802.1p/1d tag for a data frame

Parameters

struct sk_buff * skb: the data frame
struct cfg80211_qos_map * qos_map: Interworking QoS mapping or NULL if not in use

Return

The 802.1p/1d tag.

Regulatory enforcement infrastructure¶

TODO

int regulatory_hint(struct wiphy * wiphy, const char * alpha2)¶: driver hint to the wireless core a regulatory domain

Parameters

struct wiphy * wiphy: the wireless device giving the hint (used only for reporting conflicts)
const char * alpha2: the ISO/IEC 3166 alpha2 the driver claims its regulatory domain should be in. If rd is set this should be NULL. Note that if you set this to NULL you should still set rd->alpha2 to some accepted alpha2.

Description

Wireless drivers can use this function to hint to the wireless core what it believes should be the current regulatory domain by giving it an ISO/IEC 3166 alpha2 country code it knows its regulatory domain should be in or by providing a completely build regulatory domain. If the driver provides an ISO/IEC 3166 alpha2 userspace will be queried for a regulatory domain structure for the respective country.

The wiphy must have been registered to cfg80211 prior to this call. For cfg80211 drivers this means you must first use wiphy_register(), for mac80211 drivers you must first use ieee80211_register_hw().

Drivers should check the return value, its possible you can get an -ENOMEM.

Return

0 on success. -ENOMEM.

void wiphy_apply_custom_regulatory(struct wiphy * wiphy, const struct ieee80211_regdomain * regd)¶: apply a custom driver regulatory domain

Parameters

struct wiphy * wiphy: the wireless device we want to process the regulatory domain on
const struct ieee80211_regdomain * regd: the custom regulatory domain to use for this wiphy

Description

Drivers can sometimes have custom regulatory domains which do not apply to a specific country. Drivers can use this to apply such custom regulatory domains. This routine must be called prior to wiphy registration. The custom regulatory domain will be trusted completely and as such previous default channel settings will be disregarded. If no rule is found for a channel on the regulatory domain the channel will be disabled. Drivers using this for a wiphy should also set the wiphy flag REGULATORY_CUSTOM_REG or cfg80211 will set it for the wiphy that called this helper.

const struct ieee80211_reg_rule * freq_reg_info(struct wiphy * wiphy, u32 center_freq)¶: get regulatory information for the given frequency

Parameters

struct wiphy * wiphy: the wiphy for which we want to process this rule for
u32 center_freq: Frequency in KHz for which we want regulatory information for

Description

Use this function to get the regulatory rule for a specific frequency on a given wireless device. If the device has a specific regulatory domain it wants to follow we respect that unless a country IE has been received and processed already.

Return

A valid pointer, or, when an error occurs, for example if no rule can be found, the return value is encoded using ERR_PTR(). Use IS_ERR() to check and PTR_ERR() to obtain the numeric return value. The numeric return value will be -ERANGE if we determine the given center_freq does not even have a regulatory rule for a frequency range in the center_freq’s band. See freq_in_rule_band() for our current definition of a band – this is purely subjective and right now it’s 802.11 specific.

RFkill integration¶

RFkill integration in cfg80211 is almost invisible to drivers, as cfg80211 automatically registers an rfkill instance for each wireless device it knows about. Soft kill is also translated into disconnecting and turning all interfaces off, drivers are expected to turn off the device when all interfaces are down.

However, devices may have a hard RFkill line, in which case they also need to interact with the rfkill subsystem, via cfg80211. They can do this with a few helper functions documented here.

void wiphy_rfkill_set_hw_state(struct wiphy * wiphy, bool blocked)¶: notify cfg80211 about hw block state

Parameters

struct wiphy * wiphy: the wiphy
bool blocked: block status

void wiphy_rfkill_start_polling(struct wiphy * wiphy)¶: start polling rfkill

Parameters

struct wiphy * wiphy: the wiphy

void wiphy_rfkill_stop_polling(struct wiphy * wiphy)¶: stop polling rfkill

Parameters

struct wiphy * wiphy: the wiphy

Test mode¶

Test mode is a set of utility functions to allow drivers to interact with driver-specific tools to aid, for instance, factory programming.

This chapter describes how drivers interact with it, for more information see the nl80211 book’s chapter on it.

struct sk_buff * cfg80211_testmode_alloc_reply_skb(struct wiphy * wiphy, int approxlen)¶: allocate testmode reply

Parameters

struct wiphy * wiphy: the wiphy
int approxlen: an upper bound of the length of the data that will be put into the skb

Description

This function allocates and pre-fills an skb for a reply to the testmode command. Since it is intended for a reply, calling it outside of the testmode_cmd operation is invalid.

The returned skb is pre-filled with the wiphy index and set up in a way that any data that is put into the skb (with skb_put(), nla_put() or similar) will end up being within the NL80211_ATTR_TESTDATA attribute, so all that needs to be done with the skb is adding data for the corresponding userspace tool which can then read that data out of the testdata attribute. You must not modify the skb in any other way.

When done, call cfg80211_testmode_reply() with the skb and return its error code as the result of the testmode_cmd operation.

Return

An allocated and pre-filled skb. NULL if any errors happen.

int cfg80211_testmode_reply(struct sk_buff * skb)¶: send the reply skb

Parameters

struct sk_buff * skb: The skb, must have been allocated with cfg80211_testmode_alloc_reply_skb()

Description

Since calling this function will usually be the last thing before returning from the testmode_cmd you should return the error code. Note that this function consumes the skb regardless of the return value.

Return

An error code or 0 on success.

struct sk_buff * cfg80211_testmode_alloc_event_skb(struct wiphy * wiphy, int approxlen, gfp_t gfp)¶: allocate testmode event

Parameters

struct wiphy * wiphy: the wiphy
int approxlen: an upper bound of the length of the data that will be put into the skb
gfp_t gfp: allocation flags

Description

This function allocates and pre-fills an skb for an event on the testmode multicast group.

The returned skb is set up in the same way as with cfg80211_testmode_alloc_reply_skb() but prepared for an event. As there, you should simply add data to it that will then end up in the NL80211_ATTR_TESTDATA attribute. Again, you must not modify the skb in any other way.

When done filling the skb, call cfg80211_testmode_event() with the skb to send the event.

Return

An allocated and pre-filled skb. NULL if any errors happen.

void cfg80211_testmode_event(struct sk_buff * skb, gfp_t gfp)¶: send the event

Parameters

struct sk_buff * skb: The skb, must have been allocated with cfg80211_testmode_alloc_event_skb()
gfp_t gfp: allocation flags

Description

This function sends the given skb, which must have been allocated by cfg80211_testmode_alloc_event_skb(), as an event. It always consumes it.