cfg80211/mac80211: support reporting wakeup reason

When waking up from WoWLAN, it is useful to know
what triggered the wakeup. Support reporting the
wakeup reason(s) in cfg80211 (and a pass-through
in mac80211) to allow userspace to know.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

6 files changed, 226 insertions, 0 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 36e076e374d2..48add7e3ba1d 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1597,6 +1597,32 @@ struct cfg80211_wowlan {
 };
 
 /**
+ * struct cfg80211_wowlan_wakeup - wakeup report
+ * @disconnect: woke up by getting disconnected
+ * @magic_pkt: woke up by receiving magic packet
+ * @gtk_rekey_failure: woke up by GTK rekey failure
+ * @eap_identity_req: woke up by EAP identity request packet
+ * @four_way_handshake: woke up by 4-way handshake
+ * @rfkill_release: woke up by rfkill being released
+ * @pattern_idx: pattern that caused wakeup, -1 if not due to pattern
+ * @packet_present_len: copied wakeup packet data
+ * @packet_len: original wakeup packet length
+ * @packet: The packet causing the wakeup, if any.
+ * @packet_80211:  For pattern match, magic packet and other data
+ *      frame triggers an 802.3 frame should be reported, for
+ *      disconnect due to deauth 802.11 frame. This indicates which
+ *      it is.
+ */
+struct cfg80211_wowlan_wakeup {
+        bool disconnect, magic_pkt, gtk_rekey_failure,
+             eap_identity_req, four_way_handshake,
+             rfkill_release, packet_80211;
+        s32 pattern_idx;
+        u32 packet_present_len, packet_len;
+        const void *packet;
+};
+
+/**
  * struct cfg80211_gtk_rekey_data - rekey data
  * @kek: key encryption key
  * @kck: key confirmation key
@@ -3852,6 +3878,21 @@ int cfg80211_get_p2p_attr(const u8 *ies, unsigned int len,
                           enum ieee80211_p2p_attr_id attr,
                           u8 *buf, unsigned int bufsize);
 
+/**
+ * cfg80211_report_wowlan_wakeup - report wakeup from WoWLAN
+ * @wdev: the wireless device reporting the wakeup
+ * @wakeup: the wakeup report
+ * @gfp: allocation flags
+ *
+ * This function reports that the given device woke up. If it
+ * caused the wakeup, report the reason(s), otherwise you may
+ * pass %NULL as the @wakeup parameter to advertise that something
+ * else caused the wakeup.
+ */
+void cfg80211_report_wowlan_wakeup(struct wireless_dev *wdev,
+                                   struct cfg80211_wowlan_wakeup *wakeup,
+                                   gfp_t gfp);
+
 /* Logging, debugging and troubleshooting/diagnostic helpers. */
 
 /* wiphy_printk helpers, similar to dev_printk */
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 21831ee57e3c..7a27e00c513a 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -4206,4 +4206,16 @@ void ieee80211_disable_rssi_reports(struct ieee80211_vif *vif);
  */
 int ieee80211_ave_rssi(struct ieee80211_vif *vif);
 
+/**
+ * ieee80211_report_wowlan_wakeup - report WoWLAN wakeup
+ * @vif: virtual interface
+ * @wakeup: wakeup reason(s)
+ * @gfp: allocation flags
+ *
+ * See cfg80211_report_wowlan_wakeup().
+ */
+void ieee80211_report_wowlan_wakeup(struct ieee80211_vif *vif,
+                                    struct cfg80211_wowlan_wakeup *wakeup,
+                                    gfp_t gfp);
+
 #endif /* MAC80211_H */
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 5b7dbc1ea966..225a65e72219 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -513,6 +513,12 @@
  *      command with the %NL80211_ATTR_WOWLAN_TRIGGERS attribute. For
  *      more background information, see
  *      http://wireless.kernel.org/en/users/Documentation/WoWLAN.
+ *      The @NL80211_CMD_SET_WOWLAN command can also be used as a notification
+ *      from the driver reporting the wakeup reason. In this case, the
+ *      @NL80211_ATTR_WOWLAN_TRIGGERS attribute will contain the reason
+ *      for the wakeup, if it was caused by wireless. If it is not present
+ *      in the wakeup notification, the wireless device didn't cause the
+ *      wakeup but reports that it was woken up.
  *
  * @NL80211_CMD_SET_REKEY_OFFLOAD: This command is used give the driver
  *      the necessary information for supporting GTK rekey offload. This
@@ -2947,6 +2953,10 @@ struct nl80211_wowlan_pattern_support {
  *
  *      In %NL80211_ATTR_WOWLAN_TRIGGERS_SUPPORTED, it is a binary attribute
  *      carrying a &struct nl80211_wowlan_pattern_support.
+ *
+ *      When reporting wakeup. it is a u32 attribute containing the 0-based
+ *      index of the pattern that caused the wakeup, in the patterns passed
+ *      to the kernel when configuring.
  * @NL80211_WOWLAN_TRIG_GTK_REKEY_SUPPORTED: Not a real trigger, and cannot be
  *      used when setting, used only to indicate that GTK rekeying is supported
  *      by the device (flag)
@@ -2957,8 +2967,25 @@ struct nl80211_wowlan_pattern_support {
  * @NL80211_WOWLAN_TRIG_4WAY_HANDSHAKE: wake up on 4-way handshake (flag)
  * @NL80211_WOWLAN_TRIG_RFKILL_RELEASE: wake up when rfkill is released
  *      (on devices that have rfkill in the device) (flag)
+ * @NL80211_WOWLAN_TRIG_WAKEUP_PKT_80211: For wakeup reporting only, contains
+ *      the 802.11 packet that caused the wakeup, e.g. a deauth frame. The frame
+ *      may be truncated, the @NL80211_WOWLAN_TRIG_WAKEUP_PKT_80211_LEN
+ *      attribute contains the original length.
+ * @NL80211_WOWLAN_TRIG_WAKEUP_PKT_80211_LEN: Original length of the 802.11
+ *      packet, may be bigger than the @NL80211_WOWLAN_TRIG_WAKEUP_PKT_80211
+ *      attribute if the packet was truncated somewhere.
+ * @NL80211_WOWLAN_TRIG_WAKEUP_PKT_8023: For wakeup reporting only, contains the
+ *      802.11 packet that caused the wakeup, e.g. a magic packet. The frame may
+ *      be truncated, the @NL80211_WOWLAN_TRIG_WAKEUP_PKT_8023_LEN attribute
+ *      contains the original length.
+ * @NL80211_WOWLAN_TRIG_WAKEUP_PKT_8023_LEN: Original length of the 802.3
+ *      packet, may be bigger than the @NL80211_WOWLAN_TRIG_WAKEUP_PKT_8023
+ *      attribute if the packet was truncated somewhere.
  * @NUM_NL80211_WOWLAN_TRIG: number of wake on wireless triggers
  * @MAX_NL80211_WOWLAN_TRIG: highest wowlan trigger attribute number
+ *
+ * These nested attributes are used to configure the wakeup triggers and
+ * to report the wakeup reason(s).
  */
 enum nl80211_wowlan_triggers {
         __NL80211_WOWLAN_TRIG_INVALID,
@@ -2971,6 +2998,10 @@ enum nl80211_wowlan_triggers {
         NL80211_WOWLAN_TRIG_EAP_IDENT_REQUEST,
         NL80211_WOWLAN_TRIG_4WAY_HANDSHAKE,
         NL80211_WOWLAN_TRIG_RFKILL_RELEASE,
+        NL80211_WOWLAN_TRIG_WAKEUP_PKT_80211,
+        NL80211_WOWLAN_TRIG_WAKEUP_PKT_80211_LEN,
+        NL80211_WOWLAN_TRIG_WAKEUP_PKT_8023,
+        NL80211_WOWLAN_TRIG_WAKEUP_PKT_8023_LEN,
 
         /* keep last */
         NUM_NL80211_WOWLAN_TRIG,
diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
index e45b83610e85..53801d20176d 100644
--- a/net/mac80211/pm.c
+++ b/net/mac80211/pm.c
@@ -228,3 +228,13 @@ int __ieee80211_suspend(struct ieee80211_hw *hw, struct cfg80211_wowlan *wowlan)
  * ieee80211_reconfig(), which is also needed for hardware
  * hang/firmware failure/etc. recovery.
  */
+
+void ieee80211_report_wowlan_wakeup(struct ieee80211_vif *vif,
+                                    struct cfg80211_wowlan_wakeup *wakeup,
+                                    gfp_t gfp)
+{
+        struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
+
+        cfg80211_report_wowlan_wakeup(&sdata->wdev, wakeup, gfp);
+}
+EXPORT_SYMBOL(ieee80211_report_wowlan_wakeup);
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index b5978ab4ad7a..d359734b6972 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -9323,6 +9323,103 @@ void cfg80211_report_obss_beacon(struct wiphy *wiphy,
 }
 EXPORT_SYMBOL(cfg80211_report_obss_beacon);
 
+#ifdef CONFIG_PM
+void cfg80211_report_wowlan_wakeup(struct wireless_dev *wdev,
+                                   struct cfg80211_wowlan_wakeup *wakeup,
+                                   gfp_t gfp)
+{
+        struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
+        struct sk_buff *msg;
+        void *hdr;
+        int err, size = 200;
+
+        trace_cfg80211_report_wowlan_wakeup(wdev->wiphy, wdev, wakeup);
+
+        if (wakeup)
+                size += wakeup->packet_present_len;
+
+        msg = nlmsg_new(size, gfp);
+        if (!msg)
+                return;
+
+        hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_SET_WOWLAN);
+        if (!hdr)
+                goto free_msg;
+
+        if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
+            nla_put_u64(msg, NL80211_ATTR_WDEV, wdev_id(wdev)))
+                goto free_msg;
+
+        if (wdev->netdev && nla_put_u32(msg, NL80211_ATTR_IFINDEX,
+                                        wdev->netdev->ifindex))
+                goto free_msg;
+
+        if (wakeup) {
+                struct nlattr *reasons;
+
+                reasons = nla_nest_start(msg, NL80211_ATTR_WOWLAN_TRIGGERS);
+
+                if (wakeup->disconnect &&
+                    nla_put_flag(msg, NL80211_WOWLAN_TRIG_DISCONNECT))
+                        goto free_msg;
+                if (wakeup->magic_pkt &&
+                    nla_put_flag(msg, NL80211_WOWLAN_TRIG_MAGIC_PKT))
+                        goto free_msg;
+                if (wakeup->gtk_rekey_failure &&
+                    nla_put_flag(msg, NL80211_WOWLAN_TRIG_GTK_REKEY_FAILURE))
+                        goto free_msg;
+                if (wakeup->eap_identity_req &&
+                    nla_put_flag(msg, NL80211_WOWLAN_TRIG_EAP_IDENT_REQUEST))
+                        goto free_msg;
+                if (wakeup->four_way_handshake &&
+                    nla_put_flag(msg, NL80211_WOWLAN_TRIG_4WAY_HANDSHAKE))
+                        goto free_msg;
+                if (wakeup->rfkill_release &&
+                    nla_put_flag(msg, NL80211_WOWLAN_TRIG_RFKILL_RELEASE))
+                        goto free_msg;
+
+                if (wakeup->pattern_idx >= 0 &&
+                    nla_put_u32(msg, NL80211_WOWLAN_TRIG_PKT_PATTERN,
+                                wakeup->pattern_idx))
+                        goto free_msg;
+
+                if (wakeup->packet) {
+                        u32 pkt_attr = NL80211_WOWLAN_TRIG_WAKEUP_PKT_80211;
+                        u32 len_attr = NL80211_WOWLAN_TRIG_WAKEUP_PKT_80211_LEN;
+
+                        if (!wakeup->packet_80211) {
+                                pkt_attr =
+                                        NL80211_WOWLAN_TRIG_WAKEUP_PKT_8023;
+                                len_attr =
+                                        NL80211_WOWLAN_TRIG_WAKEUP_PKT_8023_LEN;
+                        }
+
+                        if (wakeup->packet_len &&
+                            nla_put_u32(msg, len_attr, wakeup->packet_len))
+                                goto free_msg;
+
+                        if (nla_put(msg, pkt_attr, wakeup->packet_present_len,
+                                    wakeup->packet))
+                                goto free_msg;
+                }
+
+                nla_nest_end(msg, reasons);
+        }
+
+        err = genlmsg_end(msg, hdr);
+        if (err < 0)
+                goto free_msg;
+
+        genlmsg_multicast_netns(wiphy_net(&rdev->wiphy), msg, 0,
+                                nl80211_mlme_mcgrp.id, gfp);
+        return;
+
+ free_msg:
+        nlmsg_free(msg);
+}
+EXPORT_SYMBOL(cfg80211_report_wowlan_wakeup);
+#endif
+
 void cfg80211_tdls_oper_request(struct net_device *dev, const u8 *peer,
                                 enum nl80211_tdls_operation oper,
                                 u16 reason_code, gfp_t gfp)
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 8bc553199686..c9cafb0ea95f 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -2333,6 +2333,41 @@ TRACE_EVENT(cfg80211_return_u32,
         TP_printk("ret: %u", __entry->ret)
 );
 
+TRACE_EVENT(cfg80211_report_wowlan_wakeup,
+        TP_PROTO(struct wiphy *wiphy, struct wireless_dev *wdev,
+                 struct cfg80211_wowlan_wakeup *wakeup),
+        TP_ARGS(wiphy, wdev, wakeup),
+        TP_STRUCT__entry(
+                WIPHY_ENTRY
+                WDEV_ENTRY
+                __field(bool, disconnect)
+                __field(bool, magic_pkt)
+                __field(bool, gtk_rekey_failure)
+                __field(bool, eap_identity_req)
+                __field(bool, four_way_handshake)
+                __field(bool, rfkill_release)
+                __field(s32, pattern_idx)
+                __field(u32, packet_len)
+                __dynamic_array(u8, packet, wakeup->packet_present_len)
+        ),
+        TP_fast_assign(
+                WIPHY_ASSIGN;
+                WDEV_ASSIGN;
+                __entry->disconnect = wakeup->disconnect;
+                __entry->magic_pkt = wakeup->magic_pkt;
+                __entry->gtk_rekey_failure = wakeup->gtk_rekey_failure;
+                __entry->eap_identity_req = wakeup->eap_identity_req;
+                __entry->four_way_handshake = wakeup->four_way_handshake;
+                __entry->rfkill_release = wakeup->rfkill_release;
+                __entry->pattern_idx = wakeup->pattern_idx;
+                __entry->packet_len = wakeup->packet_len;
+                if (wakeup->packet && wakeup->packet_present_len)
+                        memcpy(__get_dynamic_array(packet), wakeup->packet,
+                               wakeup->packet_present_len);
+        ),
+        TP_printk(WIPHY_PR_FMT ", " WDEV_PR_FMT, WIPHY_PR_ARG, WDEV_PR_ARG)
+);
+
 #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH