P2P: Address few issues seen with P2P SD

Suppose we have multiple peers and we have peers advertising SD
capability, but no services registered for advertising. In this case,
even if there are multiple broadcast queries set, we might end up
sending only the lastly added broadcast query to the same device (since
SD_INFO won't get set for the first broadcast query). Add support for
multiple wildcard queries to be tracked to enable this type of use
case.

Some times it is seen that before advancing to next device in the list,
the scan results come and update SD_SCHEDULE flag. This will result in
sending the already sent query to the same device without giving chance
to other devices. This issue again is seen with peer devices advertising
SD capability without any services registered.

Signed-off-by: Jithu Jance <jithu@broadcom.com>

src/p2p/p2p.c

@@ -733,9 +733,6 @@ int p2p_add_device(struct p2p_data *p2p, const u8 *addr, int freq,
 
 	p2p_parse_free(&msg);
 
-	if (p2p_pending_sd_req(p2p, dev))
-		dev->flags |= P2P_DEV_SD_SCHEDULE;
-
 	if (dev->flags & P2P_DEV_REPORTED)
 		return 0;
 
@@ -2406,6 +2403,7 @@ struct p2p_data * p2p_init(const struct p2p_config *cfg)
 
 	p2p->go_timeout = 100;
 	p2p->client_timeout = 20;
+	p2p->num_p2p_sd_queries = 0;
 
 	p2p_dbg(p2p, "initialized");
 	p2p_channels_dump(p2p, "channels", &p2p->cfg->channels);
@@ -2641,13 +2639,16 @@ void p2p_continue_find(struct p2p_data *p2p)
 	struct p2p_device *dev;
 	p2p_set_state(p2p, P2P_SEARCH);
 	dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
-		if (dev->flags & P2P_DEV_SD_SCHEDULE) {
-			if (p2p_start_sd(p2p, dev) == 0)
-				return;
-			else
-				break;
-		} else if (dev->req_config_methods &&
-			   !(dev->flags & P2P_DEV_PD_FOR_JOIN)) {
+		if (dev->sd_pending_bcast_queries == 0) {
+			/* Initialize with total number of registered broadcast
+			 * SD queries. */
+			dev->sd_pending_bcast_queries = p2p->num_p2p_sd_queries;
+		}
+
+		if (p2p_start_sd(p2p, dev) == 0)
+			return;
+		if (dev->req_config_methods &&
+		    !(dev->flags & P2P_DEV_PD_FOR_JOIN)) {
 			p2p_dbg(p2p, "Send pending Provision Discovery Request to "
 				MACSTR " (config methods 0x%x)",
 				MAC2STR(dev->info.p2p_device_addr),
@@ -2668,10 +2669,7 @@ static void p2p_sd_cb(struct p2p_data *p2p, int success)
 	p2p->pending_action_state = P2P_NO_PENDING_ACTION;
 
 	if (!success) {
-		if (p2p->sd_peer) {
-			p2p->sd_peer->flags &= ~P2P_DEV_SD_SCHEDULE;
-			p2p->sd_peer = NULL;
-		}
+		p2p->sd_peer = NULL;
 		p2p_continue_find(p2p);
 		return;
 	}
@@ -3216,7 +3214,6 @@ static void p2p_timeout_sd_during_find(struct p2p_data *p2p)
 	p2p_dbg(p2p, "Service Discovery Query timeout");
 	if (p2p->sd_peer) {
 		p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
-		p2p->sd_peer->flags &= ~P2P_DEV_SD_SCHEDULE;
 		p2p->sd_peer = NULL;
 	}
 	p2p_continue_find(p2p);
@@ -3487,7 +3484,7 @@ int p2p_get_peer_info_txt(const struct p2p_peer_info *info,
 			  "country=%c%c\n"
 			  "oper_freq=%d\n"
 			  "req_config_methods=0x%x\n"
-			  "flags=%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n"
+			  "flags=%s%s%s%s%s%s%s%s%s%s%s%s%s\n"
 			  "status=%d\n"
 			  "wait_count=%u\n"
 			  "invitation_reqs=%u\n",
@@ -3510,9 +3507,6 @@ int p2p_get_peer_info_txt(const struct p2p_peer_info *info,
 			  dev->flags & P2P_DEV_REPORTED ? "[REPORTED]" : "",
 			  dev->flags & P2P_DEV_NOT_YET_READY ?
 			  "[NOT_YET_READY]" : "",
-			  dev->flags & P2P_DEV_SD_INFO ? "[SD_INFO]" : "",
-			  dev->flags & P2P_DEV_SD_SCHEDULE ? "[SD_SCHEDULE]" :
-			  "",
 			  dev->flags & P2P_DEV_PD_PEER_DISPLAY ?
 			  "[PD_PEER_DISPLAY]" : "",
 			  dev->flags & P2P_DEV_PD_PEER_KEYPAD ?

src/p2p/p2p_i.h

@@ -81,8 +81,6 @@ struct p2p_device {
 #define P2P_DEV_PROBE_REQ_ONLY BIT(0)
 #define P2P_DEV_REPORTED BIT(1)
 #define P2P_DEV_NOT_YET_READY BIT(2)
-#define P2P_DEV_SD_INFO BIT(3)
-#define P2P_DEV_SD_SCHEDULE BIT(4)
 #define P2P_DEV_PD_PEER_DISPLAY BIT(5)
 #define P2P_DEV_PD_PEER_KEYPAD BIT(6)
 #define P2P_DEV_USER_REJECTED BIT(7)
@@ -110,6 +108,7 @@ struct p2p_device {
 
 	u8 go_timeout;
 	u8 client_timeout;
+	int sd_pending_bcast_queries;
 };
 
 struct p2p_sd_query {
@@ -256,6 +255,12 @@ struct p2p_data {
 	 */
 	struct p2p_sd_query *sd_query;
 
+	/**
+	 * num_p2p_sd_queries - Total number of broadcast SD queries present in
+	 * the list
+	 */
+	int num_p2p_sd_queries;
+
 	/* GO Negotiation data */
 
 	/**

src/p2p/p2p_sd.c

@@ -52,6 +52,7 @@ struct p2p_sd_query * p2p_pending_sd_req(struct p2p_data *p2p,
 {
 	struct p2p_sd_query *q;
 	int wsd = 0;
+	int count = 0;
 
 	if (!(dev->info.dev_capab & P2P_DEV_CAPAB_SERVICE_DISCOVERY))
 		return NULL; /* peer does not support SD */
@@ -64,8 +65,19 @@ struct p2p_sd_query * p2p_pending_sd_req(struct p2p_data *p2p,
 		/* Use WSD only if the peer indicates support or it */
 		if (q->wsd && !wsd)
 			continue;
-		if (q->for_all_peers && !(dev->flags & P2P_DEV_SD_INFO))
-			return q;
+		/* if the query is a broadcast query */
+		if (q->for_all_peers) {
+			/*
+			 * check if there are any broadcast queries pending for
+			 * this device
+			 */
+			if (dev->sd_pending_bcast_queries <= 0)
+				return NULL;
+			/* query number that needs to be send to the device */
+			if (count == dev->sd_pending_bcast_queries - 1)
+				return q;
+			count++;
+		}
 		if (!q->for_all_peers &&
 		    os_memcmp(q->peer, dev->info.p2p_device_addr, ETH_ALEN) ==
 		    0)
@@ -76,14 +88,37 @@ struct p2p_sd_query * p2p_pending_sd_req(struct p2p_data *p2p,
 }
 
 
+static void p2p_decrease_sd_bc_queries(struct p2p_data *p2p, int query_number)
+{
+	struct p2p_device *dev;
+
+	p2p->num_p2p_sd_queries--;
+	dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
+		if (query_number <= dev->sd_pending_bcast_queries - 1) {
+			/*
+			 * Query not yet sent to the device and it is to be
+			 * removed, so update the pending count.
+			*/
+			dev->sd_pending_bcast_queries--;
+		}
+	}
+}
+
+
 static int p2p_unlink_sd_query(struct p2p_data *p2p,
 			       struct p2p_sd_query *query)
 {
 	struct p2p_sd_query *q, *prev;
+	int query_number = 0;
+
 	q = p2p->sd_queries;
 	prev = NULL;
 	while (q) {
 		if (q == query) {
+			/* If the query is a broadcast query, decrease one from
+			 * all the devices */
+			if (query->for_all_peers)
+				p2p_decrease_sd_bc_queries(p2p, query_number);
 			if (prev)
 				prev->next = q->next;
 			else
@@ -92,6 +127,8 @@ static int p2p_unlink_sd_query(struct p2p_data *p2p,
 				p2p->sd_query = NULL;
 			return 1;
 		}
+		if (q->for_all_peers)
+			query_number++;
 		prev = q;
 		q = q->next;
 	}
@@ -118,6 +155,7 @@ void p2p_free_sd_queries(struct p2p_data *p2p)
 		q = q->next;
 		p2p_free_sd_query(prev);
 	}
+	p2p->num_p2p_sd_queries = 0;
 }
 
 
@@ -262,6 +300,16 @@ int p2p_start_sd(struct p2p_data *p2p, struct p2p_device *dev)
 		ret = -1;
 	}
 
+	/* Update the pending broadcast SD query count for this device */
+	dev->sd_pending_bcast_queries--;
+
+	/*
+	 * If there are no pending broadcast queries for this device, mark it as
+	 * done (-1).
+	 */
+	if (dev->sd_pending_bcast_queries == 0)
+		dev->sd_pending_bcast_queries = -1;
+
 	wpabuf_free(req);
 
 	return ret;
@@ -541,8 +589,6 @@ void p2p_rx_gas_initial_resp(struct p2p_data *p2p, const u8 *sa,
 	p2p_dbg(p2p, "Service Update Indicator: %u", update_indic);
 	pos += 2;
 
-	p2p->sd_peer->flags |= P2P_DEV_SD_INFO;
-	p2p->sd_peer->flags &= ~P2P_DEV_SD_SCHEDULE;
 	p2p->sd_peer = NULL;
 
 	if (p2p->sd_query) {
@@ -787,8 +833,6 @@ skip_nqp_header:
 		return;
 	}
 
-	p2p->sd_peer->flags |= P2P_DEV_SD_INFO;
-	p2p->sd_peer->flags &= ~P2P_DEV_SD_SCHEDULE;
 	p2p->sd_peer = NULL;
 
 	if (p2p->sd_query) {
@@ -841,8 +885,16 @@ void * p2p_sd_request(struct p2p_data *p2p, const u8 *dst,
 
 	if (dst == NULL) {
 		struct p2p_device *dev;
-		dl_list_for_each(dev, &p2p->devices, struct p2p_device, list)
-			dev->flags &= ~P2P_DEV_SD_INFO;
+
+		p2p->num_p2p_sd_queries++;
+
+		/* Update all the devices for the newly added broadcast query */
+		dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
+			if (dev->sd_pending_bcast_queries <= 0)
+				dev->sd_pending_bcast_queries = 1;
+			else
+				dev->sd_pending_bcast_queries++;
+		}
 	}
 
 	return q;

wpa_supplicant/README-P2P

@@ -230,9 +230,8 @@ discovery protocols and requests this to be sent to all discovered
 peers (note: this can result in long response frames). The pending
 requests are sent during device discovery (see p2p_find).
 
-Only a single pending wildcard query is supported, but there can be
-multiple pending peer device specific queries (each will be sent in
-sequence whenever the peer is found).
+There can be multiple pending peer device specific queries (each will be
+sent in sequence whenever the peer is found).
 
 This command returns an identifier for the pending query (e.g.,
 "1f77628") that can be used to cancel the request. Directed requests