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>

3 files changed, 190 insertions, 0 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 8dc807d9c29a..f1e455a8b4de 100644
--- a/include/linux/nl80211.h
+++ b/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,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 3db7dfa53b6f..fc94852e967b 100644
--- a/include/net/cfg80211.h
+++ b/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 */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 090936388528..306ae019ea81 100644
--- a/net/wireless/nl80211.c
+++ b/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 */