cfg80211/nl80211: add beacon settings

This adds the necessary API to cfg80211/nl80211 to allow
changing beaconing settings.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/nl80211.h

@@ -47,6 +47,15 @@
  * @NL80211_CMD_DEL_KEY: delete a key identified by %NL80211_ATTR_KEY_IDX
  *	or %NL80211_ATTR_MAC.
  *
+ * @NL80211_CMD_GET_BEACON: retrieve beacon information (returned in a
+ *	%NL80222_CMD_NEW_BEACON message)
+ * @NL80211_CMD_SET_BEACON: set the beacon on an access point interface
+ *	using the %NL80211_ATTR_BEACON_INTERVAL, %NL80211_ATTR_DTIM_PERIOD,
+ *	%NL80211_BEACON_HEAD and %NL80211_BEACON_TAIL attributes.
+ * @NL80211_CMD_NEW_BEACON: add a new beacon to an access point interface,
+ *	parameters are like for %NL80211_CMD_SET_BEACON.
+ * @NL80211_CMD_DEL_BEACON: remove the beacon, stop sending it
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -69,6 +78,11 @@ enum nl80211_commands {
 	NL80211_CMD_NEW_KEY,
 	NL80211_CMD_DEL_KEY,
 
+	NL80211_CMD_GET_BEACON,
+	NL80211_CMD_SET_BEACON,
+	NL80211_CMD_NEW_BEACON,
+	NL80211_CMD_DEL_BEACON,
+
 	/* add commands here */
 
 	/* used to define NL80211_CMD_MAX below */
@@ -101,6 +115,11 @@ enum nl80211_commands {
  * @NL80211_ATTR_KEY_SEQ: transmit key sequence number (IV/PN) for TKIP and
  *	CCMP keys, each six bytes in little endian
  *
+ * @NL80211_ATTR_BEACON_INTERVAL: beacon interval in TU
+ * @NL80211_ATTR_DTIM_PERIOD: DTIM period for beaconing
+ * @NL80211_ATTR_BEACON_HEAD: portion of the beacon before the TIM IE
+ * @NL80211_ATTR_BEACON_TAIL: portion of the beacon after the TIM IE
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -123,6 +142,11 @@ enum nl80211_attrs {
 	NL80211_ATTR_KEY_SEQ,
 	NL80211_ATTR_KEY_DEFAULT,
 
+	NL80211_ATTR_BEACON_INTERVAL,
+	NL80211_ATTR_DTIM_PERIOD,
+	NL80211_ATTR_BEACON_HEAD,
+	NL80211_ATTR_BEACON_TAIL,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,

include/net/cfg80211.h

@@ -69,6 +69,26 @@ struct key_params {
 	u32 cipher;
 };
 
+/**
+ * struct beacon_parameters - beacon parameters
+ *
+ * Used to configure the beacon for an interface.
+ *
+ * @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
+ * @interval: beacon interval or zero if not changed
+ * @dtim_period: DTIM period or zero if not changed
+ * @head_len: length of @head
+ * @tail_len: length of @tail
+ */
+struct beacon_parameters {
+	u8 *head, *tail;
+	int interval, dtim_period;
+	int head_len, tail_len;
+};
+
 /* from net/wireless.h */
 struct wiphy;
 
@@ -103,6 +123,13 @@ struct wiphy;
  *	and @key_index
  *
  * @set_default_key: set the default key on an interface
+ *
+ * @add_beacon: Add a beacon with given parameters, @head, @interval
+ *	and @dtim_period will be valid, @tail is optional.
+ * @set_beacon: Change the beacon parameters for an access point mode
+ *	interface. This should reject the call when no beacon has been
+ *	configured.
+ * @del_beacon: Remove beacon configuration and stop sending the beacon.
  */
 struct cfg80211_ops {
 	int	(*add_virtual_intf)(struct wiphy *wiphy, char *name,
@@ -122,6 +149,12 @@ struct cfg80211_ops {
 	int	(*set_default_key)(struct wiphy *wiphy,
 				   struct net_device *netdev,
 				   u8 key_index);
+
+	int	(*add_beacon)(struct wiphy *wiphy, struct net_device *dev,
+			      struct beacon_parameters *info);
+	int	(*set_beacon)(struct wiphy *wiphy, struct net_device *dev,
+			      struct beacon_parameters *info);
+	int	(*del_beacon)(struct wiphy *wiphy, struct net_device *dev);
 };
 
 #endif /* __NET_CFG80211_H */

net/wireless/nl80211.c

@@ -69,6 +69,13 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = {
 	[NL80211_ATTR_KEY_IDX] = { .type = NLA_U8 },
 	[NL80211_ATTR_KEY_CIPHER] = { .type = NLA_U32 },
 	[NL80211_ATTR_KEY_DEFAULT] = { .type = NLA_FLAG },
+
+	[NL80211_ATTR_BEACON_INTERVAL] = { .type = NLA_U32 },
+	[NL80211_ATTR_DTIM_PERIOD] = { .type = NLA_U32 },
+	[NL80211_ATTR_BEACON_HEAD] = { .type = NLA_BINARY,
+				       .len = IEEE80211_MAX_DATA_LEN },
+	[NL80211_ATTR_BEACON_TAIL] = { .type = NLA_BINARY,
+				       .len = IEEE80211_MAX_DATA_LEN },
 };
 
 /* message building helper */
@@ -600,6 +607,114 @@ static int nl80211_del_key(struct sk_buff *skb, struct genl_info *info)
 	return err;
 }
 
+static int nl80211_addset_beacon(struct sk_buff *skb, struct genl_info *info)
+{
+        int (*call)(struct wiphy *wiphy, struct net_device *dev,
+		    struct beacon_parameters *info);
+	struct cfg80211_registered_device *drv;
+	int err;
+	struct net_device *dev;
+	struct beacon_parameters params;
+	int haveinfo = 0;
+
+	err = get_drv_dev_by_info_ifindex(info, &drv, &dev);
+	if (err)
+		return err;
+
+	switch (info->genlhdr->cmd) {
+	case NL80211_CMD_NEW_BEACON:
+		/* these are required for NEW_BEACON */
+		if (!info->attrs[NL80211_ATTR_BEACON_INTERVAL] ||
+		    !info->attrs[NL80211_ATTR_DTIM_PERIOD] ||
+		    !info->attrs[NL80211_ATTR_BEACON_HEAD]) {
+			err = -EINVAL;
+			goto out;
+		}
+
+		call = drv->ops->add_beacon;
+		break;
+	case NL80211_CMD_SET_BEACON:
+		call = drv->ops->set_beacon;
+		break;
+	default:
+		WARN_ON(1);
+		err = -EOPNOTSUPP;
+		goto out;
+	}
+
+	if (!call) {
+		err = -EOPNOTSUPP;
+		goto out;
+	}
+
+	memset(&params, 0, sizeof(params));
+
+	if (info->attrs[NL80211_ATTR_BEACON_INTERVAL]) {
+		params.interval =
+		    nla_get_u32(info->attrs[NL80211_ATTR_BEACON_INTERVAL]);
+		haveinfo = 1;
+	}
+
+	if (info->attrs[NL80211_ATTR_DTIM_PERIOD]) {
+		params.dtim_period =
+		    nla_get_u32(info->attrs[NL80211_ATTR_DTIM_PERIOD]);
+		haveinfo = 1;
+	}
+
+	if (info->attrs[NL80211_ATTR_BEACON_HEAD]) {
+		params.head = nla_data(info->attrs[NL80211_ATTR_BEACON_HEAD]);
+		params.head_len =
+		    nla_len(info->attrs[NL80211_ATTR_BEACON_HEAD]);
+		haveinfo = 1;
+	}
+
+	if (info->attrs[NL80211_ATTR_BEACON_TAIL]) {
+		params.tail = nla_data(info->attrs[NL80211_ATTR_BEACON_TAIL]);
+		params.tail_len =
+		    nla_len(info->attrs[NL80211_ATTR_BEACON_TAIL]);
+		haveinfo = 1;
+	}
+
+	if (!haveinfo) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	rtnl_lock();
+	err = call(&drv->wiphy, dev, &params);
+	rtnl_unlock();
+
+ out:
+	cfg80211_put_dev(drv);
+	dev_put(dev);
+	return err;
+}
+
+static int nl80211_del_beacon(struct sk_buff *skb, struct genl_info *info)
+{
+	struct cfg80211_registered_device *drv;
+	int err;
+	struct net_device *dev;
+
+	err = get_drv_dev_by_info_ifindex(info, &drv, &dev);
+	if (err)
+		return err;
+
+	if (!drv->ops->del_beacon) {
+		err = -EOPNOTSUPP;
+		goto out;
+	}
+
+	rtnl_lock();
+	err = drv->ops->del_beacon(&drv->wiphy, dev);
+	rtnl_unlock();
+
+ out:
+	cfg80211_put_dev(drv);
+	dev_put(dev);
+	return err;
+}
+
 static struct genl_ops nl80211_ops[] = {
 	{
 		.cmd = NL80211_CMD_GET_WIPHY,
@@ -663,6 +778,24 @@ static struct genl_ops nl80211_ops[] = {
 		.policy = nl80211_policy,
 		.flags = GENL_ADMIN_PERM,
 	},
+	{
+		.cmd = NL80211_CMD_SET_BEACON,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+		.doit = nl80211_addset_beacon,
+	},
+	{
+		.cmd = NL80211_CMD_NEW_BEACON,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+		.doit = nl80211_addset_beacon,
+	},
+	{
+		.cmd = NL80211_CMD_DEL_BEACON,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+		.doit = nl80211_del_beacon,
+	},
 };
 
 /* multicast groups */