nl80211: add KHz frequency offset for most wifi commands

cfg80211 recently gained the ability to understand a
frequency offset component in KHz. Expose this in nl80211
through the new attributes NL80211_ATTR_WIPHY_FREQ_OFFSET,
NL80211_FREQUENCY_ATTR_OFFSET,
NL80211_ATTR_CENTER_FREQ1_OFFSET, and
NL80211_BSS_FREQUENCY_OFFSET.

These add support to send and receive a KHz offset
component with the following NL80211 commands:

- NL80211_CMD_FRAME
- NL80211_CMD_GET_SCAN
- NL80211_CMD_AUTHENTICATE
- NL80211_CMD_ASSOCIATE
- NL80211_CMD_CONNECT

Along with any other command which takes a chandef, ie:

- NL80211_CMD_SET_CHANNEL
- NL80211_CMD_SET_WIPHY
- NL80211_CMD_START_AP
- NL80211_CMD_RADAR_DETECT
- NL80211_CMD_NOTIFY_RADAR
- NL80211_CMD_CHANNEL_SWITCH
- NL80211_JOIN_IBSS
- NL80211_CMD_REMAIN_ON_CHANNEL
- NL80211_CMD_JOIN_OCB
- NL80211_CMD_JOIN_MESH
- NL80211_CMD_TDLS_CHANNEL_SWITCH

If the driver advertises a band containing channels with
frequency offset, it must also verify support for
frequency offset channels in its cfg80211 ops, or return
an error.

Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200430172554.18383-3-thomas@adapt-ip.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 58 insertions, 20 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index f6523f1485a3..87d7efd186d0 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -365,6 +365,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 
 	[NL80211_ATTR_CHANNEL_WIDTH] = { .type = NLA_U32 },
 	[NL80211_ATTR_CENTER_FREQ1] = { .type = NLA_U32 },
+	[NL80211_ATTR_CENTER_FREQ1_OFFSET] = NLA_POLICY_RANGE(NLA_U32, 0, 999),
 	[NL80211_ATTR_CENTER_FREQ2] = { .type = NLA_U32 },
 
 	[NL80211_ATTR_WIPHY_RETRY_SHORT] = NLA_POLICY_MIN(NLA_U8, 1),
@@ -638,6 +639,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_PMK_LIFETIME] = NLA_POLICY_MIN(NLA_U32, 1),
 	[NL80211_ATTR_PMK_REAUTH_THRESHOLD] = NLA_POLICY_RANGE(NLA_U8, 1, 100),
 	[NL80211_ATTR_RECEIVE_MULTICAST] = { .type = NLA_FLAG },
+	[NL80211_ATTR_WIPHY_FREQ_OFFSET] = NLA_POLICY_RANGE(NLA_U32, 0, 999),
 };
 
 /* policy for the key attributes */
@@ -904,6 +906,9 @@ static int nl80211_msg_put_channel(struct sk_buff *msg, struct wiphy *wiphy,
 			chan->center_freq))
 		goto nla_put_failure;
 
+	if (nla_put_u32(msg, NL80211_FREQUENCY_ATTR_OFFSET, chan->freq_offset))
+		goto nla_put_failure;
+
 	if ((chan->flags & IEEE80211_CHAN_DISABLED) &&
 	    nla_put_flag(msg, NL80211_FREQUENCY_ATTR_DISABLED))
 		goto nla_put_failure;
@@ -1309,13 +1314,11 @@ static int nl80211_key_allowed(struct wireless_dev *wdev)
 }
 
 static struct ieee80211_channel *nl80211_get_valid_chan(struct wiphy *wiphy,
-							struct nlattr *tb)
+							u32 freq)
 {
 	struct ieee80211_channel *chan;
 
-	if (tb == NULL)
-		return NULL;
-	chan = ieee80211_get_channel(wiphy, nla_get_u32(tb));
+	chan = ieee80211_get_channel_khz(wiphy, freq);
 	if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
 		return NULL;
 	return chan;
@@ -2770,13 +2773,17 @@ int nl80211_parse_chandef(struct cfg80211_registered_device *rdev,
 	if (!attrs[NL80211_ATTR_WIPHY_FREQ])
 		return -EINVAL;
 
-	control_freq = nla_get_u32(attrs[NL80211_ATTR_WIPHY_FREQ]);
+	control_freq = MHZ_TO_KHZ(
+			nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]));
+	if (info->attrs[NL80211_ATTR_WIPHY_FREQ_OFFSET])
+		control_freq +=
+		    nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ_OFFSET]);
 
 	memset(chandef, 0, sizeof(*chandef));
-
-	chandef->chan = ieee80211_get_channel(&rdev->wiphy, control_freq);
+	chandef->chan = ieee80211_get_channel_khz(&rdev->wiphy, control_freq);
 	chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
-	chandef->center_freq1 = control_freq;
+	chandef->center_freq1 = KHZ_TO_MHZ(control_freq);
+	chandef->freq1_offset = control_freq % 1000;
 	chandef->center_freq2 = 0;
 
 	/* Primary channel not allowed */
@@ -2824,9 +2831,15 @@ int nl80211_parse_chandef(struct cfg80211_registered_device *rdev,
 	} else if (attrs[NL80211_ATTR_CHANNEL_WIDTH]) {
 		chandef->width =
 			nla_get_u32(attrs[NL80211_ATTR_CHANNEL_WIDTH]);
-		if (attrs[NL80211_ATTR_CENTER_FREQ1])
+		if (attrs[NL80211_ATTR_CENTER_FREQ1]) {
 			chandef->center_freq1 =
 				nla_get_u32(attrs[NL80211_ATTR_CENTER_FREQ1]);
+			if (attrs[NL80211_ATTR_CENTER_FREQ1_OFFSET])
+				chandef->freq1_offset = nla_get_u32(
+				      attrs[NL80211_ATTR_CENTER_FREQ1_OFFSET]);
+			else
+				chandef->freq1_offset = 0;
+		}
 		if (attrs[NL80211_ATTR_CENTER_FREQ2])
 			chandef->center_freq2 =
 				nla_get_u32(attrs[NL80211_ATTR_CENTER_FREQ2]);
@@ -3259,6 +3272,9 @@ static int nl80211_send_chandef(struct sk_buff *msg,
 	if (nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ,
 			chandef->chan->center_freq))
 		return -ENOBUFS;
+	if (nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ_OFFSET,
+			chandef->chan->freq_offset))
+		return -ENOBUFS;
 	switch (chandef->width) {
 	case NL80211_CHAN_WIDTH_20_NOHT:
 	case NL80211_CHAN_WIDTH_20:
@@ -8873,6 +8889,8 @@ static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb,
 		goto nla_put_failure;
 	if (nla_put_u16(msg, NL80211_BSS_CAPABILITY, res->capability) ||
 	    nla_put_u32(msg, NL80211_BSS_FREQUENCY, res->channel->center_freq) ||
+	    nla_put_u32(msg, NL80211_BSS_FREQUENCY_OFFSET,
+			res->channel->freq_offset) ||
 	    nla_put_u32(msg, NL80211_BSS_CHAN_WIDTH, res->scan_width) ||
 	    nla_put_u32(msg, NL80211_BSS_SEEN_MS_AGO,
 			jiffies_to_msecs(jiffies - intbss->ts)))
@@ -9141,6 +9159,7 @@ static int nl80211_authenticate(struct sk_buff *skb, struct genl_info *info)
 	enum nl80211_auth_type auth_type;
 	struct key_parse key;
 	bool local_state_change;
+	u32 freq;
 
 	if (!info->attrs[NL80211_ATTR_MAC])
 		return -EINVAL;
@@ -9197,8 +9216,12 @@ static int nl80211_authenticate(struct sk_buff *skb, struct genl_info *info)
 		return -EOPNOTSUPP;
 
 	bssid = nla_data(info->attrs[NL80211_ATTR_MAC]);
-	chan = nl80211_get_valid_chan(&rdev->wiphy,
-				      info->attrs[NL80211_ATTR_WIPHY_FREQ]);
+	freq = MHZ_TO_KHZ(nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]));
+	if (info->attrs[NL80211_ATTR_WIPHY_FREQ_OFFSET])
+		freq +=
+		    nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ_OFFSET]);
+
+	chan = nl80211_get_valid_chan(&rdev->wiphy, freq);
 	if (!chan)
 		return -EINVAL;
 
@@ -9388,6 +9411,7 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
 	struct cfg80211_assoc_request req = {};
 	const u8 *bssid, *ssid;
 	int err, ssid_len = 0;
+	u32 freq;
 
 	if (dev->ieee80211_ptr->conn_owner_nlportid &&
 	    dev->ieee80211_ptr->conn_owner_nlportid != info->snd_portid)
@@ -9407,8 +9431,11 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
 
 	bssid = nla_data(info->attrs[NL80211_ATTR_MAC]);
 
-	chan = nl80211_get_valid_chan(&rdev->wiphy,
-				      info->attrs[NL80211_ATTR_WIPHY_FREQ]);
+	freq = MHZ_TO_KHZ(nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]));
+	if (info->attrs[NL80211_ATTR_WIPHY_FREQ_OFFSET])
+		freq +=
+		    nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ_OFFSET]);
+	chan = nl80211_get_valid_chan(&rdev->wiphy, freq);
 	if (!chan)
 		return -EINVAL;
 
@@ -10088,6 +10115,7 @@ static int nl80211_connect(struct sk_buff *skb, struct genl_info *info)
 	struct cfg80211_connect_params connect;
 	struct wiphy *wiphy;
 	struct cfg80211_cached_keys *connkeys = NULL;
+	u32 freq = 0;
 	int err;
 
 	memset(&connect, 0, sizeof(connect));
@@ -10158,14 +10186,21 @@ static int nl80211_connect(struct sk_buff *skb, struct genl_info *info)
 		connect.prev_bssid =
 			nla_data(info->attrs[NL80211_ATTR_PREV_BSSID]);
 
-	if (info->attrs[NL80211_ATTR_WIPHY_FREQ]) {
-		connect.channel = nl80211_get_valid_chan(
-			wiphy, info->attrs[NL80211_ATTR_WIPHY_FREQ]);
+	if (info->attrs[NL80211_ATTR_WIPHY_FREQ])
+		freq = MHZ_TO_KHZ(nla_get_u32(
+					info->attrs[NL80211_ATTR_WIPHY_FREQ]));
+	if (info->attrs[NL80211_ATTR_WIPHY_FREQ_OFFSET])
+		freq +=
+		    nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ_OFFSET]);
+
+	if (freq) {
+		connect.channel = nl80211_get_valid_chan(wiphy, freq);
 		if (!connect.channel)
 			return -EINVAL;
 	} else if (info->attrs[NL80211_ATTR_WIPHY_FREQ_HINT]) {
-		connect.channel_hint = nl80211_get_valid_chan(
-			wiphy, info->attrs[NL80211_ATTR_WIPHY_FREQ_HINT]);
+		freq = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ_HINT]);
+		freq = MHZ_TO_KHZ(freq);
+		connect.channel_hint = nl80211_get_valid_chan(wiphy, freq);
 		if (!connect.channel_hint)
 			return -EINVAL;
 	}
@@ -16215,6 +16250,7 @@ int nl80211_send_mgmt(struct cfg80211_registered_device *rdev,
 	    nla_put_u64_64bit(msg, NL80211_ATTR_WDEV, wdev_id(wdev),
 			      NL80211_ATTR_PAD) ||
 	    nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ, KHZ_TO_MHZ(freq)) ||
+	    nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ_OFFSET, freq % 1000) ||
 	    (sig_dbm &&
 	     nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)) ||
 	    nla_put(msg, NL80211_ATTR_FRAME, len, buf) ||
@@ -16864,8 +16900,10 @@ void cfg80211_report_obss_beacon_khz(struct wiphy *wiphy, const u8 *frame,
 
 		if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
 		    (freq &&
-		     nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ,
-				 KHZ_TO_MHZ(freq))) ||
+		     (nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ,
+				  KHZ_TO_MHZ(freq)) ||
+		      nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ_OFFSET,
+				  freq % 1000))) ||
 		    (sig_dbm &&
 		     nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)) ||
 		    nla_put(msg, NL80211_ATTR_FRAME, len, frame))