cfg80211: add wowlan net-detect support

Add a new WoWLAN API to enable net-detect as a wake up trigger.
Net-detect allows the device to scan in the background while the
host is asleep to wake up the host system when a matching network
is found.

Reuse the scheduled scan attributes to specify how the scan is
performed while suspended and the matches that will trigger a
wake event.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 110 insertions, 1 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 03a302b884fd..3ec7dc557960 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -209,7 +209,7 @@ cfg80211_get_dev_from_info(struct net *netns, struct genl_info *info)
 }
 
 /* policy for the attributes */
-static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
+static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
         [NL80211_ATTR_WIPHY] = { .type = NLA_U32 },
         [NL80211_ATTR_WIPHY_NAME] = { .type = NLA_NUL_STRING,
                                       .len = 20-1 },
@@ -428,6 +428,7 @@ nl80211_wowlan_policy[NUM_NL80211_WOWLAN_TRIG] = {
         [NL80211_WOWLAN_TRIG_4WAY_HANDSHAKE] = { .type = NLA_FLAG },
         [NL80211_WOWLAN_TRIG_RFKILL_RELEASE] = { .type = NLA_FLAG },
         [NL80211_WOWLAN_TRIG_TCP_CONNECTION] = { .type = NLA_NESTED },
+        [NL80211_WOWLAN_TRIG_NET_DETECT] = { .type = NLA_NESTED },
 };
 
 static const struct nla_policy
@@ -1088,6 +1089,8 @@ static int nl80211_send_wowlan(struct sk_buff *msg,
         if (large && nl80211_send_wowlan_tcp_caps(rdev, msg))
                 return -ENOBUFS;
 
+        /* TODO: send wowlan net detect */
+
         nla_nest_end(msg, nl_wowlan);
 
         return 0;
@@ -8695,6 +8698,39 @@ static int nl80211_parse_wowlan_tcp(struct cfg80211_registered_device *rdev,
         return 0;
 }
 
+static int nl80211_parse_wowlan_nd(struct cfg80211_registered_device *rdev,
+                                   const struct wiphy_wowlan_support *wowlan,
+                                   struct nlattr *attr,
+                                   struct cfg80211_wowlan *trig)
+{
+        struct nlattr **tb;
+        int err;
+
+        tb = kzalloc(NUM_NL80211_ATTR * sizeof(*tb), GFP_KERNEL);
+        if (!tb)
+                return -ENOMEM;
+
+        if (!(wowlan->flags & WIPHY_WOWLAN_NET_DETECT)) {
+                err = -EOPNOTSUPP;
+                goto out;
+        }
+
+        err = nla_parse(tb, NL80211_ATTR_MAX,
+                        nla_data(attr), nla_len(attr),
+                        nl80211_policy);
+        if (err)
+                goto out;
+
+        trig->nd_config = nl80211_parse_sched_scan(&rdev->wiphy, tb);
+        err = PTR_ERR_OR_ZERO(trig->nd_config);
+        if (err)
+                trig->nd_config = NULL;
+
+out:
+        kfree(tb);
+        return err;
+}
+
 static int nl80211_set_wowlan(struct sk_buff *skb, struct genl_info *info)
 {
         struct cfg80211_registered_device *rdev = info->user_ptr[0];
@@ -8840,6 +8876,14 @@ static int nl80211_set_wowlan(struct sk_buff *skb, struct genl_info *info)
                         goto error;
         }
 
+        if (tb[NL80211_WOWLAN_TRIG_NET_DETECT]) {
+                err = nl80211_parse_wowlan_nd(
+                        rdev, wowlan, tb[NL80211_WOWLAN_TRIG_NET_DETECT],
+                        &new_triggers);
+                if (err)
+                        goto error;
+        }
+
         ntrig = kmemdup(&new_triggers, sizeof(new_triggers), GFP_KERNEL);
         if (!ntrig) {
                 err = -ENOMEM;
@@ -12082,6 +12126,67 @@ void cfg80211_report_obss_beacon(struct wiphy *wiphy,
 EXPORT_SYMBOL(cfg80211_report_obss_beacon);
 
 #ifdef CONFIG_PM
+static int cfg80211_net_detect_results(struct sk_buff *msg,
+                                       struct cfg80211_wowlan_wakeup *wakeup)
+{
+        struct cfg80211_wowlan_nd_info *nd = wakeup->net_detect;
+        struct nlattr *nl_results, *nl_match, *nl_freqs;
+        int i, j;
+
+        nl_results = nla_nest_start(
+                msg, NL80211_WOWLAN_TRIG_NET_DETECT_RESULTS);
+        if (!nl_results)
+                return -EMSGSIZE;
+
+        for (i = 0; i < nd->n_matches; i++) {
+                struct cfg80211_wowlan_nd_match *match = nd->matches[i];
+
+                nl_match = nla_nest_start(msg, i);
+                if (!nl_match)
+                        break;
+
+                /* The SSID attribute is optional in nl80211, but for
+                 * simplicity reasons it's always present in the
+                 * cfg80211 structure.  If a driver can't pass the
+                 * SSID, that needs to be changed.  A zero length SSID
+                 * is still a valid SSID (wildcard), so it cannot be
+                 * used for this purpose.
+                 */
+                if (nla_put(msg, NL80211_ATTR_SSID, match->ssid.ssid_len,
+                            match->ssid.ssid)) {
+                        nla_nest_cancel(msg, nl_match);
+                        goto out;
+                }
+
+                if (match->n_channels) {
+                        nl_freqs = nla_nest_start(
+                                msg, NL80211_ATTR_SCAN_FREQUENCIES);
+                        if (!nl_freqs) {
+                                nla_nest_cancel(msg, nl_match);
+                                goto out;
+                        }
+
+                        for (j = 0; j < match->n_channels; j++) {
+                                if (nla_put_u32(msg,
+                                                NL80211_ATTR_WIPHY_FREQ,
+                                                match->channels[j])) {
+                                        nla_nest_cancel(msg, nl_freqs);
+                                        nla_nest_cancel(msg, nl_match);
+                                        goto out;
+                                }
+                        }
+
+                        nla_nest_end(msg, nl_freqs);
+                }
+
+                nla_nest_end(msg, nl_match);
+        }
+
+out:
+        nla_nest_end(msg, nl_results);
+        return 0;
+}
+
 void cfg80211_report_wowlan_wakeup(struct wireless_dev *wdev,
                                    struct cfg80211_wowlan_wakeup *wakeup,
                                    gfp_t gfp)
@@ -12176,6 +12281,10 @@ void cfg80211_report_wowlan_wakeup(struct wireless_dev *wdev,
                                 goto free_msg;
                 }
 
+                if (wakeup->net_detect &&
+                    cfg80211_net_detect_results(msg, wakeup))
+                                goto free_msg;
+
                 nla_nest_end(msg, reasons);
         }