[PATCH] cfg80211/nl80211: add a port authorized event

[PATCH] cfg80211/nl80211: add a port authorized event

[Johannes Berg]

From: Avraham Stern <avraham.stern@intel.com>

Add an event that indicates that a connection is authorized
(i.e. the 4 way handshake was performed by the driver). This event
should be sent by the driver after sending a connect/roamed event.

This is useful for networks that require 802.1X authentication.
In cases that the driver supports 4 way handshake offload, but the
802.1X authentication is managed by user space, the driver needs to
inform user space right after the 802.11 association was completed
so user space can initialize its 802.1X state machine etc.
However, it is also possible that the AP will choose to skip the
802.1X authentication (e.g. when PMKSA caching is used) and proceed
with the 4 way handshake immediately. In this case the driver needs
to inform user space that 802.1X authentication is no longer required
(e.g. to prevent user space from disconnecting since it did not get
any EAPOLs from the AP).

This is also useful for roaming, in which case it is possible that
the driver used the Fast Transition protocol so 802.1X is not
required.

Since there will now be a dedicated notification indicating that the
connection is authorized, the authorized flag can be removed from the
roamed event. Drivers can send the new port authorized event right
after sending the roamed event to indicate the new AP is already
authorized. This therefore reserves the old PORT_AUTHORIZED attribute.

Signed-off-by: Avraham Stern <avraham.stern@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 include/net/cfg80211.h       | 21 +++++++++++++++++----
 include/uapi/linux/nl80211.h | 28 ++++++++++++++++-----------
 net/wireless/core.h          |  5 +++++
 net/wireless/nl80211.c       | 34 ++++++++++++++++++++++++++++++---
 net/wireless/nl80211.h       |  2 ++
 net/wireless/sme.c           | 45 +++++++++++++++++++++++++++++++++++++++++++-
 net/wireless/util.c          |  3 +++
 7 files changed, 119 insertions(+), 19 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index cc1996081463..8b8118a7fadb 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5428,9 +5428,6 @@ cfg80211_connect_timeout(struct net_device *dev, const u8 *bssid,
  * @req_ie_len: association request IEs length
  * @resp_ie: association response IEs (may be %NULL)
  * @resp_ie_len: assoc response IEs length
- * @authorized: true if the 802.1X authentication was done by the driver or is
- *	not needed (e.g., when Fast Transition protocol was used), false
- *	otherwise. Ignored for networks that don't use 802.1X authentication.
  */
 struct cfg80211_roam_info {
 	struct ieee80211_channel *channel;
@@ -5440,7 +5437,6 @@ struct cfg80211_roam_info {
 	size_t req_ie_len;
 	const u8 *resp_ie;
 	size_t resp_ie_len;
-	bool authorized;
 };
 
 /**
@@ -5464,6 +5460,23 @@ struct cfg80211_roam_info {
 void cfg80211_roamed(struct net_device *dev, struct cfg80211_roam_info *info,
 		     gfp_t gfp);
 
+/**
+ * cfg80211_port_authorized - notify cfg80211 of successful security association
+ *
+ * @dev: network device
+ * @bssid: the BSSID of the AP
+ * @gfp: allocation flags
+ *
+ * This function should be called by a driver that supports 4 way handshake
+ * offload after a security association was successfully established (i.e.,
+ * the 4 way handshake was completed successfully). The call to this function
+ * should be preceded with a call to cfg80211_connect_result(),
+ * cfg80211_connect_done(), cfg80211_connect_bss() or cfg80211_roamed() to
+ * indicate the 802.11 association.
+ */
+void cfg80211_port_authorized(struct net_device *dev, const u8 *bssid,
+			      gfp_t gfp);
+
 /**
  * cfg80211_disconnected - notify cfg80211 that connection was dropped
  *
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 59ba6ca66a0d..95832ce03a44 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -569,13 +569,14 @@
  *	authentication/association or not receiving a response from the AP.
  *	Non-zero %NL80211_ATTR_STATUS_CODE value is indicated in that case as
  *	well to remain backwards compatible.
- * @NL80211_CMD_ROAM: notifcation indicating the card/driver roamed by itself.
- *	When the driver roamed in a network that requires 802.1X authentication,
- *	%NL80211_ATTR_PORT_AUTHORIZED should be set if the 802.1X authentication
- *	was done by the driver or if roaming was done using Fast Transition
- *	protocol (in which case 802.1X authentication is not needed). If
- *	%NL80211_ATTR_PORT_AUTHORIZED is not set, user space is responsible for
- *	the 802.1X authentication.
+ *	When establishing a security association, drivers that support 4 way
+ *	handshake offload should send %NL80211_CMD_PORT_AUTHORIZED event when
+ *	the 4 way handshake is completed successfully.
+ * @NL80211_CMD_ROAM: Notification indicating the card/driver roamed by itself.
+ *	When a security association was established with the new AP (e.g. if
+ *	the FT protocol was used for roaming or the driver completed the 4 way
+ *	handshake), this event should be followed by an
+ *	%NL80211_CMD_PORT_AUTHORIZED event.
  * @NL80211_CMD_DISCONNECT: drop a given connection; also used to notify
  *	userspace that a connection was dropped by the AP or due to other
  *	reasons, for this the %NL80211_ATTR_DISCONNECTED_BY_AP and
@@ -982,6 +983,12 @@
  * @NL80211_CMD_DEL_PMK: For offloaded 4-Way handshake, delete the previously
  *	configured PMK for the authenticator address identified by
  *	&NL80211_ATTR_MAC.
+ * @NL80211_CMD_PORT_AUTHORIZED: An event that indicates that the 4 way
+ *	handshake was completed successfully by the driver. The BSSID is
+ *	specified with &NL80211_ATTR_MAC. Drivers that support 4 way handshake
+ *	offload should send this event after indicating 802.11 association with
+ *	&NL80211_CMD_CONNECT or &NL80211_CMD_ROAM. If the 4 way handshake failed
+ *	&NL80211_CMD_DISCONNECT should be indicated instead.
  *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
@@ -1185,6 +1192,8 @@ enum nl80211_commands {
 	NL80211_CMD_SET_PMK,
 	NL80211_CMD_DEL_PMK,
 
+	NL80211_CMD_PORT_AUTHORIZED,
+
 	/* add new commands above here */
 
 	/* used to define NL80211_CMD_MAX below */
@@ -2138,10 +2147,7 @@ enum nl80211_commands {
  *	in %NL80211_CMD_CONNECT to indicate that for 802.1X authentication it
  *	wants to use the supported offload of the 4-way handshake.
  * @NL80211_ATTR_PMKR0_NAME: PMK-R0 Name for offloaded FT.
- * @NL80211_ATTR_PORT_AUTHORIZED: flag attribute used in %NL80211_CMD_ROAMED
- *	notification indicating that that 802.1X authentication was done by
- *	the driver or is not needed (because roaming used the Fast Transition
- *	protocol).
+ * @NL80211_ATTR_PORT_AUTHORIZED: (reserved)
  *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 6e809325af3b..35165f42c2a8 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -216,6 +216,7 @@ enum cfg80211_event_type {
 	EVENT_DISCONNECTED,
 	EVENT_IBSS_JOINED,
 	EVENT_STOPPED,
+	EVENT_PORT_AUTHORIZED,
 };
 
 struct cfg80211_event {
@@ -235,6 +236,9 @@ struct cfg80211_event {
 			u8 bssid[ETH_ALEN];
 			struct ieee80211_channel *channel;
 		} ij;
+		struct {
+			u8 bssid[ETH_ALEN];
+		} pa;
 	};
 };
 
@@ -385,6 +389,7 @@ int cfg80211_disconnect(struct cfg80211_registered_device *rdev,
 			bool wextev);
 void __cfg80211_roamed(struct wireless_dev *wdev,
 		       struct cfg80211_roam_info *info);
+void __cfg80211_port_authorized(struct wireless_dev *wdev, const u8 *bssid);
 int cfg80211_mgd_wext_connect(struct cfg80211_registered_device *rdev,
 			      struct wireless_dev *wdev);
 void cfg80211_autodisconnect_wk(struct work_struct *work);
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 1e39ba3cfd06..90e212db6889 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -13830,9 +13830,7 @@ void nl80211_send_roamed(struct cfg80211_registered_device *rdev,
 		     info->req_ie)) ||
 	    (info->resp_ie &&
 	     nla_put(msg, NL80211_ATTR_RESP_IE, info->resp_ie_len,
-		     info->resp_ie)) ||
-	    (info->authorized &&
-	     nla_put_flag(msg, NL80211_ATTR_PORT_AUTHORIZED)))
+		     info->resp_ie)))
 		goto nla_put_failure;
 
 	genlmsg_end(msg, hdr);
@@ -13846,6 +13844,36 @@ void nl80211_send_roamed(struct cfg80211_registered_device *rdev,
 	nlmsg_free(msg);
 }
 
+void nl80211_send_port_authorized(struct cfg80211_registered_device *rdev,
+				  struct net_device *netdev, const u8 *bssid)
+{
+	struct sk_buff *msg;
+	void *hdr;
+
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!msg)
+		return;
+
+	hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_PORT_AUTHORIZED);
+	if (!hdr) {
+		nlmsg_free(msg);
+		return;
+	}
+
+	if (nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, bssid))
+		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:
+	genlmsg_cancel(msg, hdr);
+	nlmsg_free(msg);
+}
+
 void nl80211_send_disconnected(struct cfg80211_registered_device *rdev,
 			       struct net_device *netdev, u16 reason,
 			       const u8 *ie, size_t ie_len, bool from_ap)
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index b96933322077..bf9e772a30b9 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -58,6 +58,8 @@ void nl80211_send_connect_result(struct cfg80211_registered_device *rdev,
 void nl80211_send_roamed(struct cfg80211_registered_device *rdev,
 			 struct net_device *netdev,
 			 struct cfg80211_roam_info *info, gfp_t gfp);
+void nl80211_send_port_authorized(struct cfg80211_registered_device *rdev,
+				  struct net_device *netdev, const u8 *bssid);
 void nl80211_send_disconnected(struct cfg80211_registered_device *rdev,
 			       struct net_device *netdev, u16 reason,
 			       const u8 *ie, size_t ie_len, bool from_ap);
diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index 0a49b88070d0..f38ed490e42b 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -960,7 +960,6 @@ void cfg80211_roamed(struct net_device *dev, struct cfg80211_roam_info *info,
 	ev->rm.resp_ie_len = info->resp_ie_len;
 	memcpy((void *)ev->rm.resp_ie, info->resp_ie, info->resp_ie_len);
 	ev->rm.bss = info->bss;
-	ev->rm.authorized = info->authorized;
 
 	spin_lock_irqsave(&wdev->event_lock, flags);
 	list_add_tail(&ev->list, &wdev->event_list);
@@ -969,6 +968,50 @@ void cfg80211_roamed(struct net_device *dev, struct cfg80211_roam_info *info,
 }
 EXPORT_SYMBOL(cfg80211_roamed);
 
+void __cfg80211_port_authorized(struct wireless_dev *wdev, const u8 *bssid)
+{
+	ASSERT_WDEV_LOCK(wdev);
+
+	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
+		return;
+
+	if (WARN_ON(!wdev->current_bss) ||
+	    WARN_ON(!ether_addr_equal(wdev->current_bss->pub.bssid, bssid)))
+		return;
+
+	nl80211_send_port_authorized(wiphy_to_rdev(wdev->wiphy), wdev->netdev,
+				     bssid);
+}
+
+void cfg80211_port_authorized(struct net_device *dev, const u8 *bssid,
+			      gfp_t gfp)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
+	struct cfg80211_event *ev;
+	unsigned long flags;
+
+	if (WARN_ON(!bssid))
+		return;
+
+	ev = kzalloc(sizeof(*ev), gfp);
+	if (!ev)
+		return;
+
+	ev->type = EVENT_PORT_AUTHORIZED;
+	memcpy(ev->pa.bssid, bssid, ETH_ALEN);
+
+	/*
+	 * Use the wdev event list so that if there are pending
+	 * connected/roamed events, they will be reported first.
+	 */
+	spin_lock_irqsave(&wdev->event_lock, flags);
+	list_add_tail(&ev->list, &wdev->event_list);
+	spin_unlock_irqrestore(&wdev->event_lock, flags);
+	queue_work(cfg80211_wq, &rdev->event_work);
+}
+EXPORT_SYMBOL(cfg80211_port_authorized);
+
 void __cfg80211_disconnected(struct net_device *dev, const u8 *ie,
 			     size_t ie_len, u16 reason, bool from_ap)
 {
diff --git a/net/wireless/util.c b/net/wireless/util.c
index 7a1fcc6ee060..ff21c314a609 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -846,6 +846,9 @@ void cfg80211_process_wdev_events(struct wireless_dev *wdev)
 		case EVENT_STOPPED:
 			__cfg80211_leave(wiphy_to_rdev(wdev->wiphy), wdev);
 			break;
+		case EVENT_PORT_AUTHORIZED:
+			__cfg80211_port_authorized(wdev, ev->pa.bssid);
+			break;
 		}
 		wdev_unlock(wdev);
 
-- 
2.14.1

Re: [PATCH] cfg80211/nl80211: add a port authorized event

[Arend van Spriel]

On 29-09-17 14:21, Johannes Berg wrote:
> From: Avraham Stern <avraham.stern@intel.com>
> 
> Add an event that indicates that a connection is authorized
> (i.e. the 4 way handshake was performed by the driver). This event
> should be sent by the driver after sending a connect/roamed event.

So is this event required for drivers supporting 4-way handshake 
offload. If so, the "should" above might need to be "shall" and I have 
some changes to do in brcmfmac ;-)

Regards,
Arend

Re: [PATCH] cfg80211/nl80211: add a port authorized event

[Johannes Berg]

On Mon, 2017-10-02 at 23:09 +0200, Arend van Spriel wrote:
> On 29-09-17 14:21, Johannes Berg wrote:
> > From: Avraham Stern <avraham.stern@intel.com>
> > 
> > Add an event that indicates that a connection is authorized
> > (i.e. the 4 way handshake was performed by the driver). This event
> > should be sent by the driver after sending a connect/roamed event.
> 
> So is this event required for drivers supporting 4-way handshake 
> offload. If so, the "should" above might need to be "shall" and I
> have some changes to do in brcmfmac ;-)

I'm not sure it's *required*? I guess it would be for 802.1X on the
host/4-way-HS in the device, but not necessarily for the other cases?

johannes