Bluetooth: Add support for Start Limited Discovery command

This patch implements the mgmt Start Limited Discovery command. Most
of existing Start Discovery code is reused since the only difference
is the presence of a 'limited' flag as part of the discovery state.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 372e2a7c4adadecb6417f16fbc750aa1890f9f6d..d4f82edb5cffe0528719dc416e8b28b71460e485 100644 (file)
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -77,6 +77,7 @@ struct discovery_state {
        u8                      last_adv_data_len;
        bool                    report_invalid_rssi;
        bool                    result_filtering;
+       bool                    limited;
        s8                      rssi;
        u16                     uuid_count;
        u8                      (*uuids)[16];

diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index af17774c9416c0040eb04f51c05c0fb77e890adc..ea73e0826aa7241d32a3c053cf9458fea0b34a82 100644 (file)
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -584,6 +584,8 @@ struct mgmt_rp_get_adv_size_info {
        __u8    max_scan_rsp_len;
 } __packed;
 
+#define MGMT_OP_START_LIMITED_DISCOVERY        0x0041
+
 #define MGMT_EV_CMD_COMPLETE           0x0001
 struct mgmt_ev_cmd_complete {
        __le16  opcode;

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index 9997c31ef98765fae51eb70f8b8092e98f693fbe..41b5f3813f02f1ed73ffecdc7d685645ded8c265 100644 (file)
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -1737,8 +1737,8 @@ static int le_scan_disable(struct hci_request *req, unsigned long opt)
 static int bredr_inquiry(struct hci_request *req, unsigned long opt)
 {
        u8 length = opt;
-       /* General inquiry access code (GIAC) */
-       u8 lap[3] = { 0x33, 0x8b, 0x9e };
+       const u8 giac[3] = { 0x33, 0x8b, 0x9e };
+       const u8 liac[3] = { 0x00, 0x8b, 0x9e };
        struct hci_cp_inquiry cp;
 
        BT_DBG("%s", req->hdev->name);
@@ -1748,7 +1748,12 @@ static int bredr_inquiry(struct hci_request *req, unsigned long opt)
        hci_dev_unlock(req->hdev);
 
        memset(&cp, 0, sizeof(cp));
-       memcpy(&cp.lap, lap, sizeof(cp.lap));
+
+       if (req->hdev->discovery.limited)
+               memcpy(&cp.lap, liac, sizeof(cp.lap));
+       else
+               memcpy(&cp.lap, giac, sizeof(cp.lap));
+
        cp.length = length;
 
        hci_req_add(req, HCI_OP_INQUIRY, sizeof(cp), &cp);

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 3297a4ecc05ecd4e7ecbce29047a2c1d38992447..5a5089cb6570a33d0adf91565a536172ae84301e 100644 (file)
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -103,6 +103,7 @@ static const u16 mgmt_commands[] = {
        MGMT_OP_ADD_ADVERTISING,
        MGMT_OP_REMOVE_ADVERTISING,
        MGMT_OP_GET_ADV_SIZE_INFO,
+       MGMT_OP_START_LIMITED_DISCOVERY,
 };
 
 static const u16 mgmt_events[] = {
@@ -3283,6 +3284,9 @@ void mgmt_start_discovery_complete(struct hci_dev *hdev, u8 status)
        if (!cmd)
                cmd = pending_find(MGMT_OP_START_SERVICE_DISCOVERY, hdev);
 
+       if (!cmd)
+               cmd = pending_find(MGMT_OP_START_LIMITED_DISCOVERY, hdev);
+
        if (cmd) {
                cmd->cmd_complete(cmd, mgmt_status(status));
                mgmt_pending_remove(cmd);
@@ -3318,8 +3322,8 @@ static bool discovery_type_is_valid(struct hci_dev *hdev, uint8_t type,
        return true;
 }
 
-static int start_discovery(struct sock *sk, struct hci_dev *hdev,
-                          void *data, u16 len)
+static int start_discovery_internal(struct sock *sk, struct hci_dev *hdev,
+                                   u16 op, void *data, u16 len)
 {
        struct mgmt_cp_start_discovery *cp = data;
        struct mgmt_pending_cmd *cmd;
@@ -3331,7 +3335,7 @@ static int start_discovery(struct sock *sk, struct hci_dev *hdev,
        hci_dev_lock(hdev);
 
        if (!hdev_is_powered(hdev)) {
-               err = mgmt_cmd_complete(sk, hdev->id, MGMT_OP_START_DISCOVERY,
+               err = mgmt_cmd_complete(sk, hdev->id, op,
                                        MGMT_STATUS_NOT_POWERED,
                                        &cp->type, sizeof(cp->type));
                goto failed;
@@ -3339,15 +3343,14 @@ static int start_discovery(struct sock *sk, struct hci_dev *hdev,
 
        if (hdev->discovery.state != DISCOVERY_STOPPED ||
            hci_dev_test_flag(hdev, HCI_PERIODIC_INQ)) {
-               err = mgmt_cmd_complete(sk, hdev->id, MGMT_OP_START_DISCOVERY,
-                                       MGMT_STATUS_BUSY, &cp->type,
-                                       sizeof(cp->type));
+               err = mgmt_cmd_complete(sk, hdev->id, op, MGMT_STATUS_BUSY,
+                                       &cp->type, sizeof(cp->type));
                goto failed;
        }
 
        if (!discovery_type_is_valid(hdev, cp->type, &status)) {
-               err = mgmt_cmd_complete(sk, hdev->id, MGMT_OP_START_DISCOVERY,
-                                       status, &cp->type, sizeof(cp->type));
+               err = mgmt_cmd_complete(sk, hdev->id, op, status,
+                                       &cp->type, sizeof(cp->type));
                goto failed;
        }
 
@@ -3358,8 +3361,12 @@ static int start_discovery(struct sock *sk, struct hci_dev *hdev,
 
        hdev->discovery.type = cp->type;
        hdev->discovery.report_invalid_rssi = false;
+       if (op == MGMT_OP_START_LIMITED_DISCOVERY)
+               hdev->discovery.limited = true;
+       else
+               hdev->discovery.limited = false;
 
-       cmd = mgmt_pending_add(sk, MGMT_OP_START_DISCOVERY, hdev, data, len);
+       cmd = mgmt_pending_add(sk, op, hdev, data, len);
        if (!cmd) {
                err = -ENOMEM;
                goto failed;
@@ -3376,6 +3383,21 @@ failed:
        return err;
 }
 
+static int start_discovery(struct sock *sk, struct hci_dev *hdev,
+                          void *data, u16 len)
+{
+       return start_discovery_internal(sk, hdev, MGMT_OP_START_DISCOVERY,
+                                       data, len);
+}
+
+static int start_limited_discovery(struct sock *sk, struct hci_dev *hdev,
+                                  void *data, u16 len)
+{
+       return start_discovery_internal(sk, hdev,
+                                       MGMT_OP_START_LIMITED_DISCOVERY,
+                                       data, len);
+}
+
 static int service_discovery_cmd_complete(struct mgmt_pending_cmd *cmd,
                                          u8 status)
 {
@@ -6313,6 +6335,7 @@ static const struct hci_mgmt_handler mgmt_handlers[] = {
                                                HCI_MGMT_VAR_LEN },
        { remove_advertising,      MGMT_REMOVE_ADVERTISING_SIZE },
        { get_adv_size_info,       MGMT_GET_ADV_SIZE_INFO_SIZE },
+       { start_limited_discovery, MGMT_START_DISCOVERY_SIZE },
 };
 
 void mgmt_index_added(struct hci_dev *hdev)
@@ -7237,6 +7260,18 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
                        return;
        }
 
+       if (hdev->discovery.limited) {
+               /* Check for limited discoverable bit */
+               if (dev_class) {
+                       if (!(dev_class[1] & 0x20))
+                               return;
+               } else {
+                       u8 *flags = eir_get_data(eir, eir_len, EIR_FLAGS, NULL);
+                       if (!flags || !(flags[0] & LE_AD_LIMITED))
+                               return;
+               }
+       }
+
        /* Make sure that the buffer is big enough. The 5 extra bytes
         * are for the potential CoD field.
         */