cfg80211: Add support for notifying association comeback

Thought the underline driver MLME can handle association temporal
rejection with comeback, it is still useful to notify this to
user space, as user space might want to handle the temporal
rejection differently. For example, in case the comeback time
is too long, user space can deauthenticate immediately and try
to associate with a different AP.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20211129152938.2467809e8cb3.I45574185b582666bc78eef0c29a4c36b478e5382@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index a887086cb103b6b0bb1145fbc09784a082dc7cd1..c9a9073d4c2ad9136348a7fcd8cd2608d55786fc 100644 (file)
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -8287,6 +8287,18 @@ bool cfg80211_iftype_allowed(struct wiphy *wiphy, enum nl80211_iftype iftype,
                             bool is_4addr, u8 check_swif);
 
 
+/**
+ * cfg80211_assoc_comeback - notification of association that was
+ * temporarly rejected with a comeback
+ * @netdev: network device
+ * @bss: the bss entry with which association is in progress.
+ * @timeout: timeout interval value TUs.
+ *
+ * this function may sleep. the caller must hold the corresponding wdev's mutex.
+ */
+void cfg80211_assoc_comeback(struct net_device *netdev,
+                            struct cfg80211_bss *bss, u32 timeout);
+
 /* Logging, debugging and troubleshooting/diagnostic helpers. */
 
 /* wiphy_printk helpers, similar to dev_printk */

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index bf69ecbc1c24b430e1f150eb4312abb684904e98..a8e20d25252bc5c6517df4d7e3a3f15f604724e9 100644 (file)
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1232,6 +1232,11 @@
  *     &NL80211_ATTR_FILS_NONCES - for FILS Nonces
  *             (STA Nonce 16 bytes followed by AP Nonce 16 bytes)
  *
+ * @NL80211_CMD_ASSOC_COMEBACK: notification about an association
+ *      temporal rejection with comeback. The event includes %NL80211_ATTR_MAC
+ *      to describe the BSSID address of the AP and %NL80211_ATTR_TIMEOUT to
+ *      specify the timeout value.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -1474,6 +1479,8 @@ enum nl80211_commands {
 
        NL80211_CMD_SET_FILS_AAD,
 
+       NL80211_CMD_ASSOC_COMEBACK,
+
        /* add new commands above here */
 
        /* used to define NL80211_CMD_MAX below */

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index bfa5d7428a3f46c049b9d6c75397be06c78f8596..71da0d50650268c98d02ff3bab8e0bca810280e1 100644 (file)
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -17064,6 +17064,44 @@ static void nl80211_send_remain_on_chan_event(
        nlmsg_free(msg);
 }
 
+void cfg80211_assoc_comeback(struct net_device *netdev,
+                            struct cfg80211_bss *bss, u32 timeout)
+{
+       struct wireless_dev *wdev = netdev->ieee80211_ptr;
+       struct wiphy *wiphy = wdev->wiphy;
+       struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
+       struct sk_buff *msg;
+       void *hdr;
+
+       trace_cfg80211_assoc_comeback(wdev, bss->bssid, timeout);
+
+       msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+       if (!msg)
+               return;
+
+       hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_ASSOC_COMEBACK);
+       if (!hdr) {
+               nlmsg_free(msg);
+               return;
+       }
+
+       if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
+           nla_put_u32(msg, NL80211_ATTR_IFINDEX, netdev->ifindex) ||
+           nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, bss->bssid) ||
+           nla_put_u32(msg, NL80211_ATTR_TIMEOUT, timeout))
+               goto nla_put_failure;
+
+       genlmsg_end(msg, hdr);
+
+       genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), msg, 0,
+                               NL80211_MCGRP_MLME, GFP_KERNEL);
+       return;
+
+ nla_put_failure:
+       nlmsg_free(msg);
+}
+EXPORT_SYMBOL(cfg80211_assoc_comeback);
+
 void cfg80211_ready_on_channel(struct wireless_dev *wdev, u64 cookie,
                               struct ieee80211_channel *chan,
                               unsigned int duration, gfp_t gfp)

diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index e854d52db1a6e9c1de57dba392a2aaf3ac4f563e..01710f0c8a03c551820a0420cb18ca2c66b9839c 100644 (file)
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -3696,6 +3696,23 @@ TRACE_EVENT(rdev_set_radar_offchan,
                  WIPHY_PR_ARG, CHAN_DEF_PR_ARG)
 );
 
+TRACE_EVENT(cfg80211_assoc_comeback,
+       TP_PROTO(struct wireless_dev *wdev, const u8 *bssid, u32 timeout),
+       TP_ARGS(wdev, bssid, timeout),
+       TP_STRUCT__entry(
+               WDEV_ENTRY
+               MAC_ENTRY(bssid)
+               __field(u32, timeout)
+       ),
+       TP_fast_assign(
+               WDEV_ASSIGN;
+               MAC_ASSIGN(bssid, bssid);
+               __entry->timeout = timeout;
+       ),
+       TP_printk(WDEV_PR_FMT ", " MAC_PR_FMT ", timeout: %u TUs",
+                 WDEV_PR_ARG, MAC_PR_ARG(bssid), __entry->timeout)
+);
+
 #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH