The kernel performs several regulatory checks for AP mode in
nl80211/cfg80211. These checks include radar detection,
verification of whether the sub-channel is disabled, and
an examination to determine if the channel is a DFS channel
(both DFS usable and DFS available). These checks are
performed across a frequency range, examining each sub-channel.

However, these checks are also performed on subchannels that
have been punctured which should not be examined as they are
not in use.

This leads to the issue where the AP stops because one of
the 20 MHz sub-channels is disabled or radar detected on
the channel, even when the sub-channel is punctured.

To address this issue, add a condition check wherever
regulatory checks exist for AP mode in nl80211/cfg80211.
This check identifies punctured channels and, upon finding
them, skips the regulatory checks for those channels.

Co-developed-by: Manaswini Paluri <quic_mpaluri@quicinc.com>
Signed-off-by: Manaswini Paluri <quic_mpaluri@quicinc.com>
Signed-off-by: Kavita Kavita <quic_kkavita@quicinc.com>
Link: https://patch.msgid.link/20250109050409.25351-1-quic_kkavita@quicinc.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Define a guard for the wiphy mutex, and use it in
most code in cfg80211, though not all due to some
interaction with RTNL and/or indentation.

Suggested-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Reviewed-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://patch.msgid.link/20241122094225.88765cbaab65.I610c9b14f36902e75e1d13f0db29f8bef2298804@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Preparation for allowing multiple monitor interfaces with different channels
on a multi-radio wiphy.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://patch.msgid.link/35fa652dbfebf93343f8b9a08fdef0467a2a02dc.1728462320.git-series.nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Correct spelling here and there as suggested by codespell.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Link: https://patch.msgid.link/20240913084919.118862-1-dmantipov@yandex.ru
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

On 6 GHz (and also 5 GHz to some degree), only a specific set of center
frequencies should be used depending on the channel bandwidth. Verify
this is the case on 6 GHz. For 5 GHz, we are more accepting as there are
APs that got it wrong historically.

Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240602102200.876b10a2beda.I0d3d0daea4014e99654437ff6691378dbe452652@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add a regulatory flag to allow VLP AP operation even on
channels otherwise marked NO_IR, which may be possible
in some regulatory domains/countries.

Note that this requires checking also when the beacon is
changed, since that may change the regulatory power type.

Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://msgid.link/20240523120945.63792ce19790.Ie2a02750d283b78fbf3c686b10565fb0388889e2@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

There are two functions exported now, with different settings,
refactor to just export a single function that take a struct
with different settings. This will make it easier to add more
parameters.

Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://msgid.link/20240523120945.d44c34dadfc2.I59b4403108e0dbf7fc6ae8f7522e1af520cffb1c@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

To later introduce an override for VLP APs being allowed despite
NO-IR flags, which is somewhat similar in construction to being
allowed to monitor on disabled channels, refactor the code that
checks channel flags to have not a 'monitor' argument but a set
of 'permitting' flags that permit the operation without checking
for 'prohibited' flags.

Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://msgid.link/20240523120945.3da28ded4a50.I90cffc633d0510293d511f60097dc75e719b55f0@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If the hardware supports a disabled channel, it may in
some cases be possible to use monitor mode (without any
transmit) on it when it's otherwise disabled. Add a new
channel flag IEEE80211_CHAN_CAN_MONITOR that makes it
possible for a driver to indicate such a thing.

Make it per channel so drivers could have a choice with
it, perhaps it's only possible on some channels, perhaps
some channels are not supported at all, but still there
and marked disabled.

In _nl80211_parse_chandef() simplify the code and check
only for an unknown channel, _cfg80211_chandef_usable()
will later check for IEEE80211_CHAN_DISABLED anyway.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240206164849.87fad3a21a09.I9116b2fdc2e2c9fd59a9273a64db7fcb41fc0328@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Aloka originally suggested that puncturing should be part of
the chandef, so that it's treated correctly. At the time, I
disagreed and it ended up not part of the chandef, but I've
now realized that this was wrong. Even for clients, the RX,
and perhaps more importantly, CCA configuration needs to take
puncturing into account.

Move puncturing into the chandef, and adjust all the code
accordingly. Also add a few tests for puncturing in chandef
compatibility checking.

Link: https://lore.kernel.org/linux-wireless/20220214223051.3610-1-quic_alokad@quicinc.com/
Suggested-by: Aloka Dixit <quic_alokad@quicinc.com>
Link: https://msgid.link/20240129194108.307183a5d2e5.I4d7fe2f126b2366c1312010e2900dfb2abffa0f6@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>