[PATCH] Add Support to use Resolving List

[spoorthix.k@xxxxxxxxx]

From: Spoorthi Ravishankar Koppad <spoorthix.k@xxxxxxxxx>

As per Core specification 5.0, Vol 2, Part E, Section 7.8.38,
following code changes implements LE add device to Resolving List.

Signed-off-by: Spoorthi Ravishankar Koppad <spoorthix.k@xxxxxxxxx>
---
 include/net/bluetooth/hci.h |  1 +
 net/bluetooth/hci_request.c | 72 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 73 insertions(+)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index c36dc1e..99a38cf36 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -420,6 +420,7 @@ enum {
 #define HCI_LE_SLAVE_FEATURES		0x08
 #define HCI_LE_PING			0x10
 #define HCI_LE_DATA_LEN_EXT		0x20
+#define HCI_LE_LL_PRIVACY		0x40
 #define HCI_LE_PHY_2M			0x01
 #define HCI_LE_PHY_CODED		0x08
 #define HCI_LE_EXT_ADV			0x10
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index ca73d36..48a1777 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -665,6 +665,70 @@ void hci_req_add_le_scan_disable(struct hci_request *req)
 	}
 }
 
+static void add_to_resolve_list(struct hci_request *req,
+				struct hci_conn_params *params)
+{
+	struct hci_cp_le_add_to_resolv_list cp;
+	struct bdaddr_list_with_irk *entry;
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return;
+	memset(&cp, 0, sizeof(cp));
+
+	cp.bdaddr_type = params->addr_type;
+	bacpy(&cp.bdaddr, &params->addr);
+	memcpy(entry->peer_irk, cp.peer_irk, 16);
+	memcpy(entry->local_irk, cp.local_irk, 16);
+	hci_req_add(req, HCI_OP_LE_ADD_TO_RESOLV_LIST, sizeof(cp), &cp);
+}
+
+static u8 update_resolve_list(struct hci_request *req)
+{
+	struct hci_dev *hdev = req->hdev;
+	struct hci_conn_params *params;
+	struct bdaddr_list *b;
+	int err;
+	u8 resolve_list_entries = 0;
+
+	list_for_each_entry(b, &hdev->le_resolv_list, list) {
+		/* Cannot Remove or add the device to the Resolving list
+		 * whenever there is an outstanding connection.
+		 */
+		if (!hci_pend_le_action_lookup(&hdev->pend_le_conns,
+					       &b->bdaddr, b->bdaddr_type) &&
+		    !hci_pend_le_action_lookup(&hdev->pend_le_reports,
+					       &b->bdaddr, b->bdaddr_type)) {
+			struct hci_cp_le_del_from_resolv_list cp;
+
+			cp.bdaddr_type = b->bdaddr_type;
+			bacpy(&cp.bdaddr, &b->bdaddr);
+
+			hci_req_add(req, HCI_OP_LE_DEL_FROM_RESOLV_LIST,
+				    sizeof(cp), &cp);
+			continue;
+		}
+
+		if (hci_find_irk_by_addr(hdev, &b->bdaddr, b->bdaddr_type)) {
+			/* Add device to resolving list */
+			resolve_list_entries++;
+			add_to_resolve_list(req, params);
+		}
+
+		if (hci_bdaddr_list_lookup(&hdev->le_resolv_list,
+					   &params->addr, params->addr_type))
+			continue;
+
+		if (resolve_list_entries >= hdev->le_resolv_list_size) {
+			err = smp_generate_rpa(hdev, hdev->irk, &hdev->rpa);
+			if (err < 0)
+				BT_ERR("%s failed to generate new RPA",
+				       hdev->name);
+		}
+		resolve_list_entries++;
+	}
+}
+
 static void add_to_white_list(struct hci_request *req,
 			      struct hci_conn_params *params)
 {
@@ -891,6 +955,14 @@ void hci_req_add_le_passive_scan(struct hci_request *req)
 	    (hdev->le_features[0] & HCI_LE_EXT_SCAN_POLICY))
 		filter_policy |= 0x02;
 
+	/* When filter policy is not 0x00 (no whitelist) and 0x01
+	 * (whitelist enabled) and if LE Privacy is supported in controller
+	 * add the device to resolving list.
+	 */
+	if ((filter_policy == 0x02 || filter_policy == 0x03) &&
+	    (hci_dev_test_flag(hdev, HCI_LE_LL_PRIVACY)))
+		update_resolve_list(req);
+
 	hci_req_start_scan(req, LE_SCAN_PASSIVE, hdev->le_scan_interval,
 			   hdev->le_scan_window, own_addr_type, filter_policy);
 }
-- 
1.9.1