[PATCH 1/1] Bluetooth: mgmt: Add command for getting device IO capabilities.

From: Vibhav Pant
Date: Sat Feb 10 2024 - 17:23:02 EST


get_device_io_capability allows to get a connected device's IO
capabilities, including the authentication method (and MITM support)
requested, stored in the hci_conn for the device.

Signed-off-by: Vibhav Pant <vibhavp@xxxxxxxxx>
---
include/net/bluetooth/mgmt.h | 19 ++++++++
net/bluetooth/mgmt.c | 89 ++++++++++++++++++++++++++++++++++++
2 files changed, 108 insertions(+)

diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index d382679efd2b..dba431baaef8 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -878,6 +878,25 @@ struct mgmt_cp_mesh_send_cancel {
} __packed;
#define MGMT_MESH_SEND_CANCEL_SIZE 1

+#define MGMT_OP_GET_DEVICE_IO_CAPABILITY 0x005B
+struct mgmt_cp_get_device_io_capability {
+ struct mgmt_addr_info addr;
+} __packed;
+#define MGMT_GET_DEVICE_IO_CAPABILITY_SIZE MGMT_ADDR_INFO_SIZE
+struct mgmt_rp_get_device_io_capability {
+ struct mgmt_addr_info addr;
+ __u8 flags;
+} __packed;
+
+#define MGMT_DEVICE_IO_CAP_FLAG_IO_DISPLAY_ONLY BIT(0)
+#define MGMT_DEVICE_IO_CAP_FLAG_IO_DISPLAY_YESNO BIT(1)
+#define MGMT_DEVICE_IO_CAP_FLAG_IO_KEYBOARD_ONLY BIT(2)
+#define MGMT_DEVICE_IO_CAP_FLAG_IO_NO_INPUT_OUTPUT BIT(3)
+#define MGMT_DEVICE_IO_CAP_FLAG_AT_NO_BONDING BIT(4)
+#define MGMT_DEVICE_IO_CAP_FLAG_AT_DEDICATED_BONDING BIT(5)
+#define MGMT_DEVICE_IO_CAP_FLAG_AT_GENERAL_BONDING BIT(6)
+#define MGMT_DEVICE_IO_CAP_FLAG_AT_MITM BIT(7)
+
#define MGMT_EV_CMD_COMPLETE 0x0001
struct mgmt_ev_cmd_complete {
__le16 opcode;
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 78ab562807d0..92b4317e60a1 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -28,6 +28,7 @@
#include <asm/unaligned.h>

#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/hci_sock.h>
#include <net/bluetooth/l2cap.h>
@@ -67,6 +68,7 @@ static const u16 mgmt_commands[] = {
MGMT_OP_PIN_CODE_REPLY,
MGMT_OP_PIN_CODE_NEG_REPLY,
MGMT_OP_SET_IO_CAPABILITY,
+ MGMT_OP_GET_DEVICE_IO_CAPABILITY,
MGMT_OP_PAIR_DEVICE,
MGMT_OP_CANCEL_PAIR_DEVICE,
MGMT_OP_UNPAIR_DEVICE,
@@ -3303,6 +3305,92 @@ static int set_io_capability(struct sock *sk, struct hci_dev *hdev, void *data,
NULL, 0);
}

+static int get_device_io_capability(struct sock *sk, struct hci_dev *hdev,
+ void *data, u16 len)
+{
+ struct mgmt_cp_get_device_io_capability *cp = data;
+ struct mgmt_rp_get_device_io_capability rp;
+ struct hci_conn *conn;
+ int err = 0;
+
+ bt_dev_dbg(hdev, "sock %p", sk);
+
+ memset(&rp, 0, sizeof(rp));
+ bacpy(&rp.addr.bdaddr, &cp->addr.bdaddr);
+ rp.addr.type = cp->addr.type;
+
+ if (!bdaddr_type_is_valid(cp->addr.type))
+ return mgmt_cmd_complete(sk, hdev->id,
+ MGMT_OP_GET_DEVICE_IO_CAPABILITY,
+ MGMT_STATUS_INVALID_PARAMS, &rp,
+ sizeof(rp));
+ hci_dev_lock(hdev);
+
+ if (!hdev_is_powered(hdev)) {
+ err = mgmt_cmd_complete(sk, hdev->id,
+ MGMT_OP_GET_DEVICE_IO_CAPABILITY,
+ MGMT_STATUS_NOT_POWERED, &rp,
+ sizeof(rp));
+ goto unlock;
+ }
+
+ if (cp->addr.type == BDADDR_BREDR)
+ conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK,
+ &cp->addr.bdaddr);
+ else
+ conn = hci_conn_hash_lookup_ba(hdev, LE_LINK, &cp->addr.bdaddr);
+
+ if (!conn) {
+ err = mgmt_cmd_complete(sk, hdev->id,
+ MGMT_OP_GET_DEVICE_IO_CAPABILITY,
+ MGMT_STATUS_NOT_CONNECTED, &rp,
+ sizeof(rp));
+ goto unlock;
+ }
+
+ switch (conn->remote_cap) {
+ case HCI_IO_DISPLAY_ONLY:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_IO_DISPLAY_ONLY;
+ break;
+ case HCI_IO_DISPLAY_YESNO:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_IO_DISPLAY_YESNO;
+ break;
+ case HCI_IO_KEYBOARD_ONLY:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_IO_KEYBOARD_ONLY;
+ break;
+ case HCI_IO_NO_INPUT_OUTPUT:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_IO_NO_INPUT_OUTPUT;
+ break;
+ }
+
+ switch (conn->remote_auth) {
+ case HCI_AT_NO_BONDING_MITM:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_AT_MITM;
+ fallthrough;
+ case HCI_AT_NO_BONDING:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_AT_NO_BONDING;
+ break;
+ case HCI_AT_DEDICATED_BONDING_MITM:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_AT_MITM;
+ fallthrough;
+ case HCI_AT_DEDICATED_BONDING:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_AT_DEDICATED_BONDING;
+ break;
+ case HCI_AT_GENERAL_BONDING_MITM:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_AT_MITM;
+ fallthrough;
+ case HCI_AT_GENERAL_BONDING:
+ rp.flags |= MGMT_DEVICE_IO_CAP_FLAG_AT_GENERAL_BONDING;
+ break;
+ }
+
+ err = mgmt_cmd_complete(sk, hdev->id, MGMT_OP_GET_DEVICE_IO_CAPABILITY,
+ MGMT_STATUS_SUCCESS, &rp, sizeof(rp));
+unlock:
+ hci_dev_unlock(hdev);
+ return err;
+}
+
static struct mgmt_pending_cmd *find_pairing(struct hci_conn *conn)
{
struct hci_dev *hdev = conn->hdev;
@@ -9217,6 +9305,7 @@ static const struct hci_mgmt_handler mgmt_handlers[] = {
{ pin_code_reply, MGMT_PIN_CODE_REPLY_SIZE },
{ pin_code_neg_reply, MGMT_PIN_CODE_NEG_REPLY_SIZE },
{ set_io_capability, MGMT_SET_IO_CAPABILITY_SIZE },
+ { get_device_io_capability,MGMT_GET_DEVICE_IO_CAPABILITY_SIZE },
{ pair_device, MGMT_PAIR_DEVICE_SIZE },
{ cancel_pair_device, MGMT_CANCEL_PAIR_DEVICE_SIZE },
{ unpair_device, MGMT_UNPAIR_DEVICE_SIZE },
--
2.43.0