cfg80211: add peer measurement with FTM initiator API

Add a new "peer measurement" API, that can be used to measure
certain things related to a peer. Right now, only implement
FTM (flight time measurement) over it, but the idea is that
it'll be extensible to also support measuring the necessary
things to calculate e.g. angle-of-arrival for WiGig.

The API is structured to have a generic list of peers and
channels to measure with/on, and then for each of those a
set of measurements (again, only FTM right now) to perform.

Results are sent to the requesting socket, including a final
complete message.

Closing the controlling netlink socket will abort a running
measurement.

v3:
 - add a bit to report "final" for partial results
 - remove list keeping etc. and just unicast out the results
   to the requester (big code reduction ...)
 - also send complete message unicast, and as a result
   remove the multicast group
 - separate out struct cfg80211_pmsr_ftm_request_peer
   from struct cfg80211_pmsr_request_peer
 - document timeout == 0 if no timeout
 - disallow setting timeout nl80211 attribute to 0,
   must not include attribute for no timeout
 - make MAC address randomization optional
 - change num bursts exponent default to 0 (1 burst, rather
   rather than the old default of 15==don't care)

v4:
 - clarify NL80211_ATTR_TIMEOUT documentation

v5:
 - remove unnecessary nl80211 multicast/family changes
 - remove partial results bit/flag, final is sufficient
 - add max_bursts_exponent, max_ftms_per_burst to capability
 - rename "frames per burst" -> "FTMs per burst"

v6:
 - rename cfg80211_pmsr_free_wdev() to cfg80211_pmsr_wdev_down()
   and call it in leave, so the device can't go down with any
   pending measurements

v7:
 - wording fixes (Lior)
 - fix ftm.max_bursts_exponent to allow having the limit of 0 (Lior)

v8:
 - copyright statements
 - minor coding style fixes
 - fix error path leak

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

1 files changed, 32 insertions, 0 deletions

diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index 79e47fe60c35..531c82dcba6b 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -1,4 +1,8 @@
 /* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Portions of this file
+ * Copyright (C) 2018 Intel Corporation
+ */
 #ifndef __NET_WIRELESS_NL80211_H
 #define __NET_WIRELESS_NL80211_H
 
@@ -6,6 +10,30 @@
 
 int nl80211_init(void);
 void nl80211_exit(void);
+
+extern const struct nla_policy nl80211_policy[NUM_NL80211_ATTR];
+
+void *nl80211hdr_put(struct sk_buff *skb, u32 portid, u32 seq,
+		     int flags, u8 cmd);
+bool nl80211_put_sta_rate(struct sk_buff *msg, struct rate_info *info,
+			  int attr);
+
+static inline u64 wdev_id(struct wireless_dev *wdev)
+{
+	return (u64)wdev->identifier |
+	       ((u64)wiphy_to_rdev(wdev->wiphy)->wiphy_idx << 32);
+}
+
+int nl80211_prepare_wdev_dump(struct netlink_callback *cb,
+			      struct cfg80211_registered_device **rdev,
+			      struct wireless_dev **wdev);
+
+int nl80211_parse_chandef(struct cfg80211_registered_device *rdev,
+			  struct genl_info *info,
+			  struct cfg80211_chan_def *chandef);
+int nl80211_parse_random_mac(struct nlattr **attrs,
+			     u8 *mac_addr, u8 *mac_addr_mask);
+
 void nl80211_notify_wiphy(struct cfg80211_registered_device *rdev,
 			  enum nl80211_commands cmd);
 void nl80211_notify_iface(struct cfg80211_registered_device *rdev,
@@ -95,4 +123,8 @@ void nl80211_send_ap_stopped(struct wireless_dev *wdev);
 
 void cfg80211_rdev_free_coalesce(struct cfg80211_registered_device *rdev);
 
+/* peer measurement */
+int nl80211_pmsr_start(struct sk_buff *skb, struct genl_info *info);
+int nl80211_pmsr_dump_results(struct sk_buff *skb, struct netlink_callback *cb);
+
 #endif /* __NET_WIRELESS_NL80211_H */