7 files changed, 368 insertions, 15 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index da8ea2e19273..2bfbe88837ef 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -270,6 +270,31 @@
  * @NL80211_CMD_SET_WIPHY_NETNS: Set a wiphy's netns. Note that all devices
  *      associated with this wiphy must be down and will follow.
  *
+ * @NL80211_CMD_REMAIN_ON_CHANNEL: Request to remain awake on the specified
+ *      channel for the specified amount of time. This can be used to do
+ *      off-channel operations like transmit a Public Action frame and wait for
+ *      a response while being associated to an AP on another channel.
+ *      %NL80211_ATTR_WIPHY or %NL80211_ATTR_IFINDEX is used to specify which
+ *      radio is used. %NL80211_ATTR_WIPHY_FREQ is used to specify the
+ *      frequency for the operation and %NL80211_ATTR_WIPHY_CHANNEL_TYPE may be
+ *      optionally used to specify additional channel parameters.
+ *      %NL80211_ATTR_DURATION is used to specify the duration in milliseconds
+ *      to remain on the channel. This command is also used as an event to
+ *      notify when the requested duration starts (it may take a while for the
+ *      driver to schedule this time due to other concurrent needs for the
+ *      radio).
+ *      When called, this operation returns a cookie (%NL80211_ATTR_COOKIE)
+ *      that will be included with any events pertaining to this request;
+ *      the cookie is also used to cancel the request.
+ * @NL80211_CMD_CANCEL_REMAIN_ON_CHANNEL: This command can be used to cancel a
+ *      pending remain-on-channel duration if the desired operation has been
+ *      completed prior to expiration of the originally requested duration.
+ *      %NL80211_ATTR_WIPHY or %NL80211_ATTR_IFINDEX is used to specify the
+ *      radio. The %NL80211_ATTR_COOKIE attribute must be given as well to
+ *      uniquely identify the request.
+ *      This command is also used as an event to notify when a requested
+ *      remain-on-channel duration has expired.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -353,6 +378,9 @@ enum nl80211_commands {
         NL80211_CMD_DEL_PMKSA,
         NL80211_CMD_FLUSH_PMKSA,
 
+        NL80211_CMD_REMAIN_ON_CHANNEL,
+        NL80211_CMD_CANCEL_REMAIN_ON_CHANNEL,
+
         /* add new commands above here */
 
         /* used to define NL80211_CMD_MAX below */
@@ -606,6 +634,10 @@ enum nl80211_commands {
  * @NL80211_ATTR_MAX_NUM_PMKIDS: maximum number of PMKIDs a firmware can
  *      cache, a wiphy attribute.
  *
+ * @NL80211_ATTR_DURATION: Duration of an operation in milliseconds, u32.
+ *
+ * @NL80211_ATTR_COOKIE: Generic 64-bit cookie to identify objects.
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -743,6 +775,10 @@ enum nl80211_attrs {
         NL80211_ATTR_PMKID,
         NL80211_ATTR_MAX_NUM_PMKIDS,
 
+        NL80211_ATTR_DURATION,
+
+        NL80211_ATTR_COOKIE,
+
         /* 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 542a477a94da..b66beb052054 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -988,6 +988,15 @@ struct cfg80211_pmksa {
  *
  * @dump_survey: get site survey information.
  *
+ * @remain_on_channel: Request the driver to remain awake on the specified
+ *      channel for the specified duration to complete an off-channel
+ *      operation (e.g., public action frame exchange). When the driver is
+ *      ready on the requested channel, it must indicate this with an event
+ *      notification by calling cfg80211_ready_on_channel().
+ * @cancel_remain_on_channel: Cancel an on-going remain-on-channel operation.
+ *      This allows the operation to be terminated prior to timeout based on
+ *      the duration value.
+ *
  * @testmode_cmd: run a test mode command
  *
  * @set_pmksa: Cache a PMKID for a BSSID. This is mostly useful for fullmac
@@ -1123,6 +1132,16 @@ struct cfg80211_ops {
                              struct cfg80211_pmksa *pmksa);
         int     (*flush_pmksa)(struct wiphy *wiphy, struct net_device *netdev);
 
+        int     (*remain_on_channel)(struct wiphy *wiphy,
+                                     struct net_device *dev,
+                                     struct ieee80211_channel *chan,
+                                     enum nl80211_channel_type channel_type,
+                                     unsigned int duration,
+                                     u64 *cookie);
+        int     (*cancel_remain_on_channel)(struct wiphy *wiphy,
+                                            struct net_device *dev,
+                                            u64 cookie);
+
         /* some temporary stuff to finish wext */
         int     (*set_power_mgmt)(struct wiphy *wiphy, struct net_device *dev,
                                   bool enabled, int timeout);
@@ -2147,5 +2166,33 @@ void cfg80211_roamed(struct net_device *dev, const u8 *bssid,
 void cfg80211_disconnected(struct net_device *dev, u16 reason,
                            u8 *ie, size_t ie_len, gfp_t gfp);
 
+/**
+ * cfg80211_ready_on_channel - notification of remain_on_channel start
+ * @dev: network device
+ * @cookie: the request cookie
+ * @chan: The current channel (from remain_on_channel request)
+ * @channel_type: Channel type
+ * @duration: Duration in milliseconds that the driver intents to remain on the
+ *      channel
+ * @gfp: allocation flags
+ */
+void cfg80211_ready_on_channel(struct net_device *dev, u64 cookie,
+                               struct ieee80211_channel *chan,
+                               enum nl80211_channel_type channel_type,
+                               unsigned int duration, gfp_t gfp);
+
+/**
+ * cfg80211_remain_on_channel_expired - remain_on_channel duration expired
+ * @dev: network device
+ * @cookie: the request cookie
+ * @chan: The current channel (from remain_on_channel request)
+ * @channel_type: Channel type
+ * @gfp: allocation flags
+ */
+void cfg80211_remain_on_channel_expired(struct net_device *dev,
+                                        u64 cookie,
+                                        struct ieee80211_channel *chan,
+                                        enum nl80211_channel_type channel_type,
+                                        gfp_t gfp);
 
 #endif /* __NET_CFG80211_H */
diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index a46ac6c9b365..bf1737fc9a7e 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -41,44 +41,57 @@ rdev_fixed_channel(struct cfg80211_registered_device *rdev,
         return result;
 }
 
-int rdev_set_freq(struct cfg80211_registered_device *rdev,
-                  struct wireless_dev *for_wdev,
+struct ieee80211_channel *
+rdev_freq_to_chan(struct cfg80211_registered_device *rdev,
                   int freq, enum nl80211_channel_type channel_type)
 {
         struct ieee80211_channel *chan;
         struct ieee80211_sta_ht_cap *ht_cap;
-        int result;
-
-        if (rdev_fixed_channel(rdev, for_wdev))
-                return -EBUSY;
-
-        if (!rdev->ops->set_channel)
-                return -EOPNOTSUPP;
 
         chan = ieee80211_get_channel(&rdev->wiphy, freq);
 
         /* Primary channel not allowed */
         if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
-                return -EINVAL;
+                return NULL;
 
         if (channel_type == NL80211_CHAN_HT40MINUS &&
             chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
-                return -EINVAL;
+                return NULL;
         else if (channel_type == NL80211_CHAN_HT40PLUS &&
                  chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
-                return -EINVAL;
+                return NULL;
 
         ht_cap = &rdev->wiphy.bands[chan->band]->ht_cap;
 
         if (channel_type != NL80211_CHAN_NO_HT) {
                 if (!ht_cap->ht_supported)
-                        return -EINVAL;
+                        return NULL;
 
                 if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
                     ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
-                        return -EINVAL;
+                        return NULL;
         }
 
+        return chan;
+}
+
+int rdev_set_freq(struct cfg80211_registered_device *rdev,
+                  struct wireless_dev *for_wdev,
+                  int freq, enum nl80211_channel_type channel_type)
+{
+        struct ieee80211_channel *chan;
+        int result;
+
+        if (rdev_fixed_channel(rdev, for_wdev))
+                return -EBUSY;
+
+        if (!rdev->ops->set_channel)
+                return -EOPNOTSUPP;
+
+        chan = rdev_freq_to_chan(rdev, freq, channel_type);
+        if (!chan)
+                return -EINVAL;
+
         result = rdev->ops->set_channel(&rdev->wiphy, chan, channel_type);
         if (result)
                 return result;
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 35b712127143..30ec95f05b52 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -374,6 +374,9 @@ void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev);
 struct ieee80211_channel *
 rdev_fixed_channel(struct cfg80211_registered_device *rdev,
                    struct wireless_dev *for_wdev);
+struct ieee80211_channel *
+rdev_freq_to_chan(struct cfg80211_registered_device *rdev,
+                  int freq, enum nl80211_channel_type channel_type);
 int rdev_set_freq(struct cfg80211_registered_device *rdev,
                   struct wireless_dev *for_wdev,
                   int freq, enum nl80211_channel_type channel_type);
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index acaeaa784d68..11f6469b3f98 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -680,3 +680,30 @@ void cfg80211_mlme_down(struct cfg80211_registered_device *rdev,
                 }
         }
 }
+
+void cfg80211_ready_on_channel(struct net_device *dev, u64 cookie,
+                               struct ieee80211_channel *chan,
+                               enum nl80211_channel_type channel_type,
+                               unsigned int duration, gfp_t gfp)
+{
+        struct wiphy *wiphy = dev->ieee80211_ptr->wiphy;
+        struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
+
+        nl80211_send_remain_on_channel(rdev, dev, cookie, chan, channel_type,
+                                       duration, gfp);
+}
+EXPORT_SYMBOL(cfg80211_ready_on_channel);
+
+void cfg80211_remain_on_channel_expired(struct net_device *dev,
+                                        u64 cookie,
+                                        struct ieee80211_channel *chan,
+                                        enum nl80211_channel_type channel_type,
+                                        gfp_t gfp)
+{
+        struct wiphy *wiphy = dev->ieee80211_ptr->wiphy;
+        struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
+
+        nl80211_send_remain_on_channel_cancel(rdev, dev, cookie, chan,
+                                              channel_type, gfp);
+}
+EXPORT_SYMBOL(cfg80211_remain_on_channel_expired);
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 60f854377f90..ff857f10cb85 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -141,6 +141,8 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = {
         [NL80211_ATTR_4ADDR] = { .type = NLA_U8 },
         [NL80211_ATTR_PMKID] = { .type = NLA_BINARY,
                                  .len = WLAN_PMKID_LEN },
+        [NL80211_ATTR_DURATION] = { .type = NLA_U32 },
+        [NL80211_ATTR_COOKIE] = { .type = NLA_U64 },
 };
 
 /* policy for the attributes */
@@ -569,6 +571,7 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
         CMD(set_pmksa, SET_PMKSA);
         CMD(del_pmksa, DEL_PMKSA);
         CMD(flush_pmksa, FLUSH_PMKSA);
+        CMD(remain_on_channel, REMAIN_ON_CHANNEL);
         if (dev->wiphy.flags & WIPHY_FLAG_NETNS_OK) {
                 i++;
                 NLA_PUT_U32(msg, i, NL80211_CMD_SET_WIPHY_NETNS);
@@ -4283,6 +4286,143 @@ static int nl80211_flush_pmksa(struct sk_buff *skb, struct genl_info *info)
 
 }
 
+static int nl80211_remain_on_channel(struct sk_buff *skb,
+                                     struct genl_info *info)
+{
+        struct cfg80211_registered_device *rdev;
+        struct net_device *dev;
+        struct ieee80211_channel *chan;
+        struct sk_buff *msg;
+        void *hdr;
+        u64 cookie;
+        enum nl80211_channel_type channel_type = NL80211_CHAN_NO_HT;
+        u32 freq, duration;
+        int err;
+
+        if (!info->attrs[NL80211_ATTR_WIPHY_FREQ] ||
+            !info->attrs[NL80211_ATTR_DURATION])
+                return -EINVAL;
+
+        duration = nla_get_u32(info->attrs[NL80211_ATTR_DURATION]);
+
+        /*
+         * We should be on that channel for at least one jiffie,
+         * and more than 5 seconds seems excessive.
+         */
+        if (!duration || !msecs_to_jiffies(duration) || duration > 5000)
+                return -EINVAL;
+
+        rtnl_lock();
+
+        err = get_rdev_dev_by_info_ifindex(info, &rdev, &dev);
+        if (err)
+                goto unlock_rtnl;
+
+        if (!rdev->ops->remain_on_channel) {
+                err = -EOPNOTSUPP;
+                goto out;
+        }
+
+        if (!netif_running(dev)) {
+                err = -ENETDOWN;
+                goto out;
+        }
+
+        if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]) {
+                channel_type = nla_get_u32(
+                        info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]);
+                if (channel_type != NL80211_CHAN_NO_HT &&
+                    channel_type != NL80211_CHAN_HT20 &&
+                    channel_type != NL80211_CHAN_HT40PLUS &&
+                    channel_type != NL80211_CHAN_HT40MINUS)
+                        err = -EINVAL;
+                        goto out;
+        }
+
+        freq = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]);
+        chan = rdev_freq_to_chan(rdev, freq, channel_type);
+        if (chan == NULL) {
+                err = -EINVAL;
+                goto out;
+        }
+
+        msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+        if (!msg) {
+                err = -ENOMEM;
+                goto out;
+        }
+
+        hdr = nl80211hdr_put(msg, info->snd_pid, info->snd_seq, 0,
+                             NL80211_CMD_REMAIN_ON_CHANNEL);
+
+        if (IS_ERR(hdr)) {
+                err = PTR_ERR(hdr);
+                goto free_msg;
+        }
+
+        err = rdev->ops->remain_on_channel(&rdev->wiphy, dev, chan,
+                                           channel_type, duration, &cookie);
+
+        if (err)
+                goto free_msg;
+
+        NLA_PUT_U64(msg, NL80211_ATTR_COOKIE, cookie);
+
+        genlmsg_end(msg, hdr);
+        err = genlmsg_reply(msg, info);
+        goto out;
+
+ nla_put_failure:
+        err = -ENOBUFS;
+ free_msg:
+        nlmsg_free(msg);
+ out:
+        cfg80211_unlock_rdev(rdev);
+        dev_put(dev);
+ unlock_rtnl:
+        rtnl_unlock();
+        return err;
+}
+
+static int nl80211_cancel_remain_on_channel(struct sk_buff *skb,
+                                            struct genl_info *info)
+{
+        struct cfg80211_registered_device *rdev;
+        struct net_device *dev;
+        u64 cookie;
+        int err;
+
+        if (!info->attrs[NL80211_ATTR_COOKIE])
+                return -EINVAL;
+
+        rtnl_lock();
+
+        err = get_rdev_dev_by_info_ifindex(info, &rdev, &dev);
+        if (err)
+                goto unlock_rtnl;
+
+        if (!rdev->ops->cancel_remain_on_channel) {
+                err = -EOPNOTSUPP;
+                goto out;
+        }
+
+        if (!netif_running(dev)) {
+                err = -ENETDOWN;
+                goto out;
+        }
+
+        cookie = nla_get_u64(info->attrs[NL80211_ATTR_COOKIE]);
+
+        err = rdev->ops->cancel_remain_on_channel(&rdev->wiphy, dev, cookie);
+
+ out:
+        cfg80211_unlock_rdev(rdev);
+        dev_put(dev);
+ unlock_rtnl:
+        rtnl_unlock();
+        return err;
+}
+
 static struct genl_ops nl80211_ops[] = {
         {
                 .cmd = NL80211_CMD_GET_WIPHY,
@@ -4545,8 +4685,20 @@ static struct genl_ops nl80211_ops[] = {
                 .policy = nl80211_policy,
                 .flags = GENL_ADMIN_PERM,
         },
-
+        {
+                .cmd = NL80211_CMD_REMAIN_ON_CHANNEL,
+                .doit = nl80211_remain_on_channel,
+                .policy = nl80211_policy,
+                .flags = GENL_ADMIN_PERM,
+        },
+        {
+                .cmd = NL80211_CMD_CANCEL_REMAIN_ON_CHANNEL,
+                .doit = nl80211_cancel_remain_on_channel,
+                .policy = nl80211_policy,
+                .flags = GENL_ADMIN_PERM,
+        },
 };
+
 static struct genl_multicast_group nl80211_mlme_mcgrp = {
         .name = "mlme",
 };
@@ -5134,6 +5286,70 @@ nla_put_failure:
         nlmsg_free(msg);
 }
 
+static void nl80211_send_remain_on_chan_event(
+        int cmd, struct cfg80211_registered_device *rdev,
+        struct net_device *netdev, u64 cookie,
+        struct ieee80211_channel *chan,
+        enum nl80211_channel_type channel_type,
+        unsigned int duration, gfp_t gfp)
+{
+        struct sk_buff *msg;
+        void *hdr;
+
+        msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
+        if (!msg)
+                return;
+
+        hdr = nl80211hdr_put(msg, 0, 0, 0, cmd);
+        if (!hdr) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx);
+        NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, netdev->ifindex);
+        NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_FREQ, chan->center_freq);
+        NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_CHANNEL_TYPE, channel_type);
+        NLA_PUT_U64(msg, NL80211_ATTR_COOKIE, cookie);
+
+        if (cmd == NL80211_CMD_REMAIN_ON_CHANNEL)
+                NLA_PUT_U32(msg, NL80211_ATTR_DURATION, duration);
+
+        if (genlmsg_end(msg, hdr) < 0) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        genlmsg_multicast_netns(wiphy_net(&rdev->wiphy), msg, 0,
+                                nl80211_mlme_mcgrp.id, gfp);
+        return;
+
+ nla_put_failure:
+        genlmsg_cancel(msg, hdr);
+        nlmsg_free(msg);
+}
+
+void nl80211_send_remain_on_channel(struct cfg80211_registered_device *rdev,
+                                    struct net_device *netdev, u64 cookie,
+                                    struct ieee80211_channel *chan,
+                                    enum nl80211_channel_type channel_type,
+                                    unsigned int duration, gfp_t gfp)
+{
+        nl80211_send_remain_on_chan_event(NL80211_CMD_REMAIN_ON_CHANNEL,
+                                          rdev, netdev, cookie, chan,
+                                          channel_type, duration, gfp);
+}
+
+void nl80211_send_remain_on_channel_cancel(
+        struct cfg80211_registered_device *rdev, struct net_device *netdev,
+        u64 cookie, struct ieee80211_channel *chan,
+        enum nl80211_channel_type channel_type, gfp_t gfp)
+{
+        nl80211_send_remain_on_chan_event(NL80211_CMD_CANCEL_REMAIN_ON_CHANNEL,
+                                          rdev, netdev, cookie, chan,
+                                          channel_type, 0, gfp);
+}
+
 /* initialisation/exit functions */
 
 int nl80211_init(void)
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index 44cc2a76a1b0..a5e2de419b7a 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -59,4 +59,15 @@ void nl80211_send_ibss_bssid(struct cfg80211_registered_device *rdev,
                              struct net_device *netdev, const u8 *bssid,
                              gfp_t gfp);
 
+void nl80211_send_remain_on_channel(struct cfg80211_registered_device *rdev,
+                                    struct net_device *netdev,
+                                    u64 cookie,
+                                    struct ieee80211_channel *chan,
+                                    enum nl80211_channel_type channel_type,
+                                    unsigned int duration, gfp_t gfp);
+void nl80211_send_remain_on_channel_cancel(
+        struct cfg80211_registered_device *rdev, struct net_device *netdev,
+        u64 cookie, struct ieee80211_channel *chan,
+        enum nl80211_channel_type channel_type, gfp_t gfp);
+
 #endif /* __NET_WIRELESS_NL80211_H */