measurement: add handling of measurements

Add logic for saving measurement-reports from STAs.

This commit does not yet save the measurement-reports received from
clients but adds the necessary code to do so. Currently the codes can
only handle beacon-reports, but link measurements can be added to it in
the future.

It also adds the new config-key measurement_report_timeout which
controls how long measurements are saved upon they are received by a
STA.

Signed-off-by: David Bauer <mail@david-bauer.net>

CMakeLists.txt

@@ -24,7 +24,7 @@ IF(NOT HAVE_PCAP_H)
 	MESSAGE(FATAL_ERROR "pcap/pcap.h is not found")
 ENDIF()
 
-SET(SOURCES main.c local_node.c node.c sta.c policy.c ubus.c remote.c parse.c netifd.c timeout.c event.c)
+SET(SOURCES main.c local_node.c node.c sta.c policy.c ubus.c remote.c parse.c netifd.c timeout.c event.c measurement.c)
 
 IF(NL_CFLAGS)
 	ADD_DEFINITIONS(${NL_CFLAGS})

local_node.c

@@ -71,6 +71,7 @@ usteer_free_node(struct ubus_context *ctx, struct usteer_local_node *ln)
 	usteer_local_node_pending_bss_tm_free(ln);
 	usteer_local_node_state_reset(ln);
 	usteer_sta_node_cleanup(&ln->node);
+	usteer_measurement_report_node_cleanup(&ln->node);
 	uloop_timeout_cancel(&ln->update);
 	uloop_timeout_cancel(&ln->bss_tm_queries_timeout);
 	avl_delete(&local_nodes, &ln->node.avl);
@@ -578,6 +579,7 @@ usteer_get_node(struct ubus_context *ctx, const char *name)
 	avl_insert(&local_nodes, &node->avl);
 	kvlist_init(&ln->node_info, kvlist_blob_len);
 	INIT_LIST_HEAD(&node->sta_info);
+	INIT_LIST_HEAD(&node->measurements);
 
 	ln->bss_tm_queries_timeout.cb = usteer_local_node_process_bss_tm_queries;
 	INIT_LIST_HEAD(&ln->bss_tm_queries);
@@ -623,6 +625,7 @@ usteer_check_node_enabled(struct usteer_local_node *ln)
 		MSG(INFO, "Disconnecting from local node %s\n", usteer_node_name(&ln->node));
 		usteer_local_node_state_reset(ln);
 		usteer_sta_node_cleanup(&ln->node);
+		usteer_measurement_report_node_cleanup(&ln->node);
 		uloop_timeout_cancel(&ln->update);
 		ubus_unsubscribe(ubus_ctx, &ln->ev, ln->obj_id);
 		return;

main.c

@@ -86,6 +86,7 @@ void usteer_init_defaults(void)
 
 	config.sta_block_timeout = 30 * 1000;
 	config.local_sta_timeout = 120 * 1000;
+	config.measurement_report_timeout = 120 * 1000;
 	config.local_sta_update = 1 * 1000;
 	config.max_retry_band = 5;
 	config.max_neighbor_reports = 8;

measurement.c

@@ -0,0 +1,112 @@
+/*
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+ *
+ *   Copyright (C) 2021 David Bauer <mail@david-bauer.net> 
+ */
+
+#include "usteer.h"
+
+LIST_HEAD(measurements);
+static struct usteer_timeout_queue tq;
+
+void
+usteer_measurement_report_node_cleanup(struct usteer_node *node)
+{
+	struct usteer_measurement_report *mr, *tmp;
+
+	list_for_each_entry_safe(mr, tmp, &node->measurements, node_list)
+		usteer_measurement_report_del(mr);
+}
+
+void
+usteer_measurement_report_sta_cleanup(struct sta *sta)
+{
+	struct usteer_measurement_report *mr, *tmp;
+
+	list_for_each_entry_safe(mr, tmp, &sta->measurements, sta_list)
+		usteer_measurement_report_del(mr);
+}
+
+struct usteer_measurement_report *
+usteer_measurement_report_get(struct sta *sta, struct usteer_node *node, bool create)
+{
+	struct usteer_measurement_report *mr;
+
+	list_for_each_entry(mr, &sta->measurements, sta_list) {
+		if (mr->node == node)
+			return mr;
+	}
+
+	if (!create)
+		return NULL;
+
+	mr = calloc(1, sizeof(*mr));
+	if (!mr)
+		return NULL;
+
+	/* Set node & add to nodes list */
+	mr->node = node;
+	list_add(&mr->node_list, &node->measurements);
+
+	/* Set sta & add to STAs list */
+	mr->sta = sta;
+	list_add(&mr->sta_list, &sta->measurements);
+
+	/* Add to Measurement list */
+	list_add(&mr->list, &measurements);
+
+	/* Set measurement expiration */
+	usteer_timeout_set(&tq, &mr->timeout, config.measurement_report_timeout);
+
+	return mr;
+}
+
+struct usteer_measurement_report *
+usteer_measurement_report_add_beacon_report(struct sta *sta, struct usteer_node *node,
+					    struct usteer_beacon_report *br, uint64_t timestamp)
+{
+	struct usteer_measurement_report *mr = usteer_measurement_report_get(sta, node, true);
+
+	if (!mr)
+		return NULL;
+
+	mr->timestamp = timestamp;
+	memcpy(&mr->beacon_report, br, sizeof(*br));
+
+	return mr;
+}
+
+void
+usteer_measurement_report_del(struct usteer_measurement_report *mr)
+{
+	usteer_timeout_cancel(&tq, &mr->timeout);
+	list_del(&mr->node_list);
+	list_del(&mr->sta_list);
+	list_del(&mr->list);
+	free(mr);
+}
+
+static void
+usteer_measurement_timeout(struct usteer_timeout_queue *q, struct usteer_timeout *t)
+{
+	struct usteer_measurement_report *mr = container_of(t, struct usteer_measurement_report, timeout);
+
+	usteer_measurement_report_del(mr);
+}
+
+static void __usteer_init usteer_measurement_init(void)
+{
+	usteer_timeout_init(&tq);
+	tq.cb = usteer_measurement_timeout;
+}

openwrt/usteer/files/etc/config/usteer

@@ -26,6 +26,9 @@ config usteer
 	# Maximum amount of time (ms) a local unconnected station is tracked
 	#option local_sta_timeout 120000
 
+	# Maximum amount of time (ms) a measurement report is stored
+	#option measurement_report_timeout 120000
+
 	# Local station information update interval (ms)
 	#option local_sta_update 1000
 

openwrt/usteer/files/etc/init.d/usteer

@@ -76,6 +76,7 @@ uci_usteer() {
 		debug_level \
 		sta_block_timeout local_sta_timeout local_sta_update \
 		max_neighbor_reports max_retry_band seen_policy_timeout \
+		measurement_report_timeout \
 		load_balancing_threshold band_steering_threshold \
 		remote_update_interval remote_node_timeout\
 		min_connect_snr min_snr min_snr_kick_delay signal_diff_threshold \

remote.c

@@ -210,6 +210,7 @@ remote_node_free(struct usteer_remote_node *node)
 	list_del(&node->list);
 	list_del(&node->host_list);
 	usteer_sta_node_cleanup(&node->node);
+	usteer_measurement_report_node_cleanup(&node->node);
 	free(node);
 
 	if (!list_empty(&host->nodes))
@@ -264,6 +265,7 @@ interface_get_node(struct usteer_remote_host *host, const char *name)
 	node->name = buf + addr_len + 1;
 	node->host = host;
 	INIT_LIST_HEAD(&node->node.sta_info);
+	INIT_LIST_HEAD(&node->node.measurements);
 
 	list_add_tail(&node->list, &remote_nodes);
 	list_add_tail(&node->host_list, &host->nodes);

sta.c

@@ -35,6 +35,7 @@ usteer_sta_del(struct sta *sta)
 	    MAC_ADDR_DATA(sta->addr));
 
 	avl_delete(&stations, &sta->avl);
+	usteer_measurement_report_sta_cleanup(sta);
 	free(sta);
 }
 
@@ -140,6 +141,7 @@ usteer_sta_get(const uint8_t *addr, bool create)
 	sta->avl.key = sta->addr;
 	avl_insert(&stations, &sta->avl);
 	INIT_LIST_HEAD(&sta->nodes);
+	INIT_LIST_HEAD(&sta->measurements);
 
 	return sta;
 }

ubus.c

@@ -149,6 +149,7 @@ struct cfg_item {
 	_cfg(U32, max_neighbor_reports), \
 	_cfg(U32, max_retry_band), \
 	_cfg(U32, seen_policy_timeout), \
+	_cfg(U32, measurement_report_timeout), \
 	_cfg(U32, load_balancing_threshold), \
 	_cfg(U32, band_steering_threshold), \
 	_cfg(U32, remote_update_interval), \

usteer.h

@@ -73,6 +73,7 @@ struct usteer_remote_host;
 struct usteer_node {
 	struct avl_node avl;
 	struct list_head sta_info;
+	struct list_head measurements;
 
 	enum usteer_node_type type;
 
@@ -155,6 +156,7 @@ struct usteer_config {
 
 	uint32_t max_retry_band;
 	uint32_t seen_policy_timeout;
+	uint32_t measurement_report_timeout;
 
 	bool assoc_steering;
 
@@ -254,6 +256,7 @@ struct sta_info {
 struct sta {
 	struct avl_node avl;
 	struct list_head nodes;
+	struct list_head measurements;
 
 	uint8_t seen_2ghz : 1;
 	uint8_t seen_5ghz : 1;
@@ -263,6 +266,27 @@ struct sta {
 	uint8_t rrm;
 };
 
+struct usteer_beacon_report {
+	uint8_t rcpi;
+	uint8_t rsni;
+};
+
+struct usteer_measurement_report {
+	struct usteer_timeout timeout;
+
+	struct list_head list;
+
+	struct usteer_node *node;
+	struct list_head node_list;
+
+	struct sta *sta;
+	struct list_head sta_list;
+
+	uint64_t timestamp;
+
+	struct usteer_beacon_report beacon_report;
+};
+
 extern struct ubus_context *ubus_ctx;
 extern struct usteer_config config;
 extern struct list_head node_handlers;
@@ -335,4 +359,12 @@ void usteer_run_hook(const char *name, const char *arg);
 void usteer_dump_node(struct blob_buf *buf, struct usteer_node *node);
 void usteer_dump_host(struct blob_buf *buf, struct usteer_remote_host *host);
 
+struct usteer_measurement_report * usteer_measurement_report_get(struct sta *sta, struct usteer_node *node, bool create);
+void usteer_measurement_report_node_cleanup(struct usteer_node *node);
+void usteer_measurement_report_sta_cleanup(struct sta *sta);
+void usteer_measurement_report_del(struct usteer_measurement_report *mr);
+
+struct usteer_measurement_report *
+usteer_measurement_report_add_beacon_report(struct sta *sta, struct usteer_node *node, struct usteer_beacon_report *br, uint64_t timestamp);
+
 #endif