SCANNING AND BSS LIST HANDLING(9)

📦 version 7.3.1, in nixpkgs unstable

🌸 Scanning and BSS list handling 🌸

okay so this is the Scanning and BSS list handling(9) page from the Kernel API Manual, and bestie, it's giving "small but mighty" energy. let's get into it 💅

So the scanning process itself? honestly kind of simple, lowkey. but cfg80211 is out here offering quite a bit of helper functionality — like it's that friend who brings snacks to the study session and also has a full color-coded spreadsheet. iconic behavior, honestly 🫶

✨ starting a scan ✨

To start a scan, the scan operation gets invoked with a scan definition. and what's in that scan definition, you ask? 👀

  • the channels to scan
  • the SSIDs to send probe requests for (including the wildcard, if that's what you're into)

A passive scan is indicated by having no SSIDs to probe — so like, no SSIDs, no active probing, it's just vibing and listening 💀

Additionally, a scan request may contain extra information elements that should get added to the probe request. and here's the slay part: the IEs are guaranteed to be well-formed ✨ and they will not exceed the maximum length that the driver advertised in the wiphy structure. so no surprise chaos, they stay within the limits the driver set. respect. 👑

🦋 found a BSS? tell cfg80211 🦋

When scanning finds a BSS, cfg80211 needs to be notified of that — because it is the one responsible for maintaining the BSS list, periodt. the driver should not maintain a list itself, no cap. and for this notification? various functions exist. pick your fighter, they're there for you 💖

🎀 searching and sharing 🎀

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 that cfg80211 maintains. so cfg80211 holds the data, you just go ask it nicely 🌸

oh and — the BSS list is also made available to userspace. everybody eats 🍓

okay that's the whole vibe for this part, but there's literally more where this came from 🌈

✨ SEE ALSO ✨

Kernel file ./include/net/cfg80211.h — yes bestie, all of these live in that one header. One file. One. Iconic behaviour honestly 🎀

Okay so this is the big reference list, and it is long — so grab a snack, hydrate, and let's go through it together. I'm keeping every single one because every single one matters 💅

That's the capability-and-band era of the list, and yes there are both a _ieee80211_set_sband_iftype_data and an ieee80211_set_sband_iftype_data — one little underscore, two whole entries, no I will not be merging them 🙈

  • Actions and configuration(9)
  • struct vif_params(9)
  • struct key_params(9)
  • struct cfg80211_chan_def(9)
  • struct cfg80211_tid_cfg(9)
  • struct cfg80211_tid_config(9)
  • struct cfg80211_fils_aad(9)
  • struct cfg80211_set_hw_timestamp(9)
  • cfg80211_get_chandef_type(9)
  • cfg80211_chandef_create(9)
  • cfg80211_chandef_identical(9)
  • cfg80211_chandef_is_edmg(9)
  • cfg80211_chandef_is_s1g(9)
  • cfg80211_chandef_compatible(9)
  • nl80211_chan_width_to_mhz(9)
  • cfg80211_chandef_get_width(9)
  • cfg80211_chandef_valid(9)
  • cfg80211_chandef_usable(9)
  • cfg80211_chandef_dfs_required(9)
  • cfg80211_chandef_dfs_usable(9)
  • cfg80211_chandef_dfs_cac_time(9)
  • cfg80211_chandef_primary(9)
  • cfg80211_chandef_npca_valid(9)
  • cfg80211_chandef_add_npca(9)
  • cfg80211_chandef_add_dbe(9)
  • nl80211_send_chandef(9)
  • ieee80211_chandef_max_power(9)
  • cfg80211_chandef_s1g_pri_width(9)
  • cfg80211_any_usable_channels(9)
  • enum survey_info_flags(9)
  • struct survey_info(9)
  • struct cfg80211_crypto_settings(9)
  • struct cfg80211_mbssid_config(9)
  • struct cfg80211_mbssid_elems(9)
  • struct cfg80211_rnr_elems(9)
  • struct cfg80211_beacon_data(9)
  • struct cfg80211_acl_data(9)
  • struct cfg80211_fils_discovery(9)
  • struct cfg80211_unsol_bcast_probe_resp(9)
  • struct cfg80211_s1g_short_beacon(9)
  • struct cfg80211_ap_settings(9)
  • struct cfg80211_ap_update(9)
  • struct cfg80211_csa_settings(9)
  • struct cfg80211_color_change_settings(9)
  • struct iface_combination_params(9)
  • enum station_parameters_apply_mask(9)
  • struct sta_txpwr(9)
  • struct link_station_parameters(9)
  • struct link_station_del_parameters(9)
  • struct cfg80211_ttlm_params(9)
  • struct station_parameters(9)
  • struct station_del_parameters(9)
  • enum cfg80211_station_type(9)
  • cfg80211_check_station_change(9)
  • enum rate_info_flags(9)
  • enum rate_info_bw(9)
  • struct rate_info(9)
  • enum bss_param_flags(9)
  • struct sta_bss_parameters(9)
  • struct cfg80211_txq_stats(9)
  • struct cfg80211_tid_stats(9)
  • struct link_station_info(9)
  • struct station_info(9)
  • struct cfg80211_sar_sub_specs(9)
  • struct cfg80211_sar_specs(9)
  • struct cfg80211_sar_freq_ranges(9)
  • struct cfg80211_sar_capa(9)
  • cfg80211_get_station(9)
  • enum monitor_flags(9)
  • enum mpath_info_flags(9)
  • struct mpath_info(9)
  • enum wiphy_bss_param_flags(9)
  • struct bss_parameters(9)
  • struct mesh_config(9)
  • struct mesh_setup(9)
  • struct ocb_setup(9)
  • struct ieee80211_txq_params(9)
  • struct cfg80211_ssid(9)
  • struct cfg80211_scan_info(9)
  • struct cfg80211_scan_6ghz_params(9)
  • struct cfg80211_scan_request(9)
  • struct cfg80211_match_set(9)
  • struct cfg80211_sched_scan_plan(9)
  • struct cfg80211_bss_select_adjust(9)
  • struct cfg80211_sched_scan_request(9)
  • enum cfg80211_signal_type(9)
  • struct cfg80211_inform_bss(9)
  • struct cfg80211_bss_ies(9)
  • struct cfg80211_bss(9)
  • ieee80211_bss_get_elem(9)
  • ieee80211_bss_get_ie(9)
  • struct cfg80211_auth_request(9)
  • struct cfg80211_assoc_link(9)
  • struct cfg80211_ml_reconf_req(9)
  • enum cfg80211_assoc_req_flags(9)
  • struct cfg80211_assoc_request(9)
  • struct cfg80211_deauth_request(9)
  • struct cfg80211_disassoc_request(9)
  • struct cfg80211_ibss_params(9)
  • struct cfg80211_bss_selection(9)
  • struct cfg80211_connect_params(9)
  • enum cfg80211_connect_params_changed(9)
  • enum wiphy_params_flags(9)
  • struct cfg80211_pmksa(9)
  • struct cfg80211_pkt_pattern(9)
  • struct cfg80211_wowlan_tcp(9)
  • struct cfg80211_wowlan(9)
  • struct cfg80211_coalesce_rules(9)
  • struct cfg80211_coalesce(9)
  • struct cfg80211_wowlan_nd_match(9)
  • struct cfg80211_wowlan_nd_info(9)
  • struct cfg80211_wowlan_wakeup(9)
  • struct cfg80211_gtk_rekey_data(9)
  • struct cfg80211_update_ft_ies_params(9)
  • struct cfg80211_mgmt_tx_params(9)
  • struct cfg80211_dscp_exception(9)
  • struct cfg80211_dscp_range(9)
  • struct cfg80211_qos_map(9)

Alphabetical-ish would've been nice but no, we're vibing through the structs in file order, and honestly? Respect 🫶

The whole wiphy_work_* / wiphy_delayed_work_* / wiphy_hrtimer_work_* family is here in full — queue, cancel, flush, and (for the delayed + hrtimer ones) pending. Four flavours each, no cap 💀

Note that ieee80211_channel_to_khz, ieee80211_channel_to_freq_khz and ieee80211_channel_to_frequency are all separate entries, and so are ieee80211_freq_khz_to_channel and ieee80211_frequency_to_channel — yes the khz and non-khz versions both exist, keep them straight bestie 🦋

The finder family is fully intact: elem, ie, elem_match, ie_match, ext_elem, ext_ie, vendor_elem, vendor_ie. Eight of them. All distinct. Do not @ me 😭

Heads up: __cfg80211_get_bss(9) and cfg80211_get_bss(9) are both on here — the double-underscore one is its own entry, so don't go thinking they're the same thing ✨

And that's the whole reference list, bestie — every last (9) accounted for, nothing dropped, nothing renamed 💖 Three-hundred-plus entries and we got through them all. If you were looking for something and it's not here, then it's not in the SEE ALSO, periodt 🫶

okay so the SEE ALSO fam is huge — like, this is the extended-extended family and they all pulled up to the group chat at once 💖. Every single one, no skips, no cap, in order:

and that's the whole page, bestie — you made it to the end of all three parts 🎉 like genuinely, go hydrate. this one lives over in ./include/net, dated October 2026, and it's part of the Kernel API Manual as Scanning and...ist handling(9). bye ily, go read the actual pages now 💖✨

📦 where this page comes from