cfg80211: keep track of supported interface modes

It is obviously good for userspace to know up front which
interface modes a given piece of hardware might support (even
if adding such an interface might fail later because of
concurrency issues), so let's make cfg80211 aware of that.
For good measure, disallow adding interfaces in all other
modes so drivers don't forget to announce support for one mode
when they add it.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Stephen Blackheath <tramp.enshrine.stephen@blacksapphire.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/adm8211.c

@@ -1884,6 +1884,7 @@ static int __devinit adm8211_probe(struct pci_dev *pdev,
 	dev->extra_tx_headroom = sizeof(struct adm8211_tx_hdr);
 	/* dev->flags = IEEE80211_HW_RX_INCLUDES_FCS in promisc mode */
 	dev->flags = IEEE80211_HW_SIGNAL_UNSPEC;
+	dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
 
 	dev->channel_change_time = 1000;
 	dev->max_signal = 100;    /* FIXME: find better value */

drivers/net/wireless/ath5k/base.c

@@ -485,6 +485,12 @@ ath5k_pci_probe(struct pci_dev *pdev,
 	hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
 		    IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
+
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC) |
+		BIT(NL80211_IFTYPE_MESH_POINT);
+
 	hw->extra_tx_headroom = 2;
 	hw->channel_change_time = 5000;
 	sc = hw->priv;

drivers/net/wireless/ath9k/main.c

@@ -1482,6 +1482,11 @@ static int ath_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		IEEE80211_HW_SIGNAL_DBM |
 		IEEE80211_HW_NOISE_DBM;
 
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC);
+
 	SET_IEEE80211_DEV(hw, &pdev->dev);
 	pci_set_drvdata(pdev, hw);
 

drivers/net/wireless/b43/main.c

@@ -4569,6 +4569,13 @@ static int b43_wireless_init(struct ssb_device *dev)
 		    IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
 
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_MESH_POINT) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_WDS) |
+		BIT(NL80211_IFTYPE_ADHOC);
+
 	hw->queues = b43_modparam_qos ? 4 : 1;
 	SET_IEEE80211_DEV(hw, dev->dev);
 	if (is_valid_ether_addr(sprom->et1mac))

drivers/net/wireless/b43legacy/main.c

@@ -3704,6 +3704,11 @@ static int b43legacy_wireless_init(struct ssb_device *dev)
 	hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
 		    IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_WDS) |
+		BIT(NL80211_IFTYPE_ADHOC);
 	hw->queues = 1; /* FIXME: hardware has more queues */
 	SET_IEEE80211_DEV(hw, dev->dev);
 	if (is_valid_ether_addr(sprom->et1mac))

drivers/net/wireless/iwlwifi/iwl-core.c

@@ -819,6 +819,10 @@ int iwl_setup_mac(struct iwl_priv *priv)
 	/* Tell mac80211 our characteristics */
 	hw->flags = IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC);
 	/* Default value; 4 EDCA QOS priorities */
 	hw->queues = 4;
 	/* queues to support 11n aggregation */

drivers/net/wireless/iwlwifi/iwl3945-base.c

@@ -7888,6 +7888,11 @@ static int iwl3945_pci_probe(struct pci_dev *pdev, const struct pci_device_id *e
 	hw->flags = IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
 
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC);
+
 	/* 4 EDCA QOS priorities */
 	hw->queues = 4;
 

drivers/net/wireless/mac80211_hwsim.c

@@ -447,6 +447,9 @@ static int __init init_mac80211_hwsim(void)
 
 		hw->channel_change_time = 1;
 		hw->queues = 4;
+		hw->wiphy->interface_modes =
+			BIT(NL80211_IFTYPE_STATION) |
+			BIT(NL80211_IFTYPE_AP);
 		hw->ampdu_queues = 1;
 
 		memcpy(data->channels, hwsim_channels, sizeof(hwsim_channels));

drivers/net/wireless/p54/p54common.c

@@ -1072,6 +1072,9 @@ struct ieee80211_hw *p54_init_common(size_t priv_data_len)
 	dev->flags = IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING | /* not sure */
 		     IEEE80211_HW_RX_INCLUDES_FCS |
 		     IEEE80211_HW_SIGNAL_UNSPEC;
+
+	dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
+
 	dev->channel_change_time = 1000;	/* TODO: find actual value */
 	dev->max_signal = 127;
 

drivers/net/wireless/rt2x00/rt2x00dev.c

@@ -1052,6 +1052,11 @@ int rt2x00lib_probe_dev(struct rt2x00_dev *rt2x00dev)
 	 */
 	rt2x00dev->hw->vif_data_size = sizeof(struct rt2x00_intf);
 
+	rt2x00dev->hw->wiphy->interface_modes =
+	    BIT(NL80211_IFTYPE_AP) |
+	    BIT(NL80211_IFTYPE_STATION) |
+	    BIT(NL80211_IFTYPE_ADHOC);
+
 	/*
 	 * Let the driver probe the device to detect the capabilities.
 	 */

drivers/net/wireless/rtl8187_dev.c

@@ -1184,6 +1184,8 @@ static int __devinit rtl8187_probe(struct usb_interface *intf,
 		dev->max_signal = 65;
 	}
 
+	dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
+
 	if ((id->driver_info == DEVICE_RTL8187) && priv->is_rtl8187b)
 		printk(KERN_INFO "rtl8187: inconsistency between id with OEM"
 		       " info!\n");

drivers/net/wireless/zd1211rw/zd_mac.c

@@ -937,6 +937,11 @@ struct ieee80211_hw *zd_mac_alloc_hw(struct usb_interface *intf)
 	hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
 		    IEEE80211_HW_SIGNAL_DB;
 
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_MESH_POINT) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC);
+
 	hw->max_signal = 100;
 	hw->queues = 1;
 	hw->extra_tx_headroom = sizeof(struct zd_ctrlset);

include/linux/nl80211.h

@@ -210,6 +210,10 @@ enum nl80211_commands {
  * @NL80211_ATTR_HT_CAPABILITY: HT Capability information element (from
  *	association request when used with NL80211_CMD_NEW_STATION)
  *
+ * @NL80211_ATTR_SUPPORTED_IFTYPES: nested attribute containing all
+ *	supported interface types, each a flag attribute with the number
+ *	of the interface mode.
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -259,6 +263,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_HT_CAPABILITY,
 
+	NL80211_ATTR_SUPPORTED_IFTYPES,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,

include/net/wireless.h

@@ -185,6 +185,9 @@ struct wiphy {
 	/* permanent MAC address */
 	u8 perm_addr[ETH_ALEN];
 
+	/* Supported interface modes, OR together BIT(NL80211_IFTYPE_...) */
+	u16 interface_modes;
+
 	/* If multiple wiphys are registered and you're handed e.g.
 	 * a regular netdev with assigned ieee80211_ptr, you won't
 	 * know whether it points to a wiphy your driver has registered

net/mac80211/main.c

@@ -1675,6 +1675,13 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 		}
 	}
 
+	/* if low-level driver supports AP, we also support VLAN */
+	if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_AP))
+		local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_AP_VLAN);
+
+	/* mac80211 always supports monitor */
+	local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_MONITOR);
+
 	result = wiphy_register(local->hw.wiphy);
 	if (result < 0)
 		return result;

net/wireless/core.c

@@ -1,7 +1,7 @@
 /*
  * This is the linux wireless configuration interface.
  *
- * Copyright 2006, 2007		Johannes Berg <johannes@sipsolutions.net>
+ * Copyright 2006-2008		Johannes Berg <johannes@sipsolutions.net>
  */
 
 #include <linux/if.h>
@@ -259,6 +259,13 @@ int wiphy_register(struct wiphy *wiphy)
 	struct ieee80211_supported_band *sband;
 	bool have_band = false;
 	int i;
+	u16 ifmodes = wiphy->interface_modes;
+
+	/* sanity check ifmodes */
+	WARN_ON(!ifmodes);
+	ifmodes &= ((1 << __NL80211_IFTYPE_AFTER_LAST) - 1) & ~1;
+	if (WARN_ON(ifmodes != wiphy->interface_modes))
+		wiphy->interface_modes = ifmodes;
 
 	/* sanity check supported bands/channels */
 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {

net/wireless/nl80211.c

@@ -113,10 +113,12 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
 	struct nlattr *nl_bands, *nl_band;
 	struct nlattr *nl_freqs, *nl_freq;
 	struct nlattr *nl_rates, *nl_rate;
+	struct nlattr *nl_modes;
 	enum ieee80211_band band;
 	struct ieee80211_channel *chan;
 	struct ieee80211_rate *rate;
 	int i;
+	u16 ifmodes = dev->wiphy.interface_modes;
 
 	hdr = nl80211hdr_put(msg, pid, seq, flags, NL80211_CMD_NEW_WIPHY);
 	if (!hdr)
@@ -125,6 +127,20 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
 	NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, dev->idx);
 	NLA_PUT_STRING(msg, NL80211_ATTR_WIPHY_NAME, wiphy_name(&dev->wiphy));
 
+	nl_modes = nla_nest_start(msg, NL80211_ATTR_SUPPORTED_IFTYPES);
+	if (!nl_modes)
+		goto nla_put_failure;
+
+	i = 0;
+	while (ifmodes) {
+		if (ifmodes & 1)
+			NLA_PUT_FLAG(msg, i);
+		ifmodes >>= 1;
+		i++;
+	}
+
+	nla_nest_end(msg, nl_modes);
+
 	nl_bands = nla_nest_start(msg, NL80211_ATTR_WIPHY_BANDS);
 	if (!nl_bands)
 		goto nla_put_failure;
@@ -415,7 +431,8 @@ static int nl80211_set_interface(struct sk_buff *skb, struct genl_info *info)
 	ifindex = dev->ifindex;
 	dev_put(dev);
 
-	if (!drv->ops->change_virtual_intf) {
+	if (!drv->ops->change_virtual_intf ||
+	    !(drv->wiphy.interface_modes & (1 << type))) {
 		err = -EOPNOTSUPP;
 		goto unlock;
 	}
@@ -462,7 +479,8 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
 	if (IS_ERR(drv))
 		return PTR_ERR(drv);
 
-	if (!drv->ops->add_virtual_intf) {
+	if (!drv->ops->add_virtual_intf ||
+	    !(drv->wiphy.interface_modes & (1 << type))) {
 		err = -EOPNOTSUPP;
 		goto unlock;
 	}