diff options
author | Johan Hedberg <johan.hedberg@intel.com> | 2015-06-11 13:52:29 +0300 |
---|---|---|
committer | Marcel Holtmann <marcel@holtmann.org> | 2015-06-12 11:38:45 +0200 |
commit | 821f37666815c9f3a7a4d195ce9184ad4d084942 (patch) | |
tree | 36596eee3edfdaf72e6ee5e0cee6bec31eb574c9 | |
parent | 035ad621b6e625e185fe7b6929788d1d83727079 (diff) | |
download | op-kernel-dev-821f37666815c9f3a7a4d195ce9184ad4d084942.zip op-kernel-dev-821f37666815c9f3a7a4d195ce9184ad4d084942.tar.gz |
Bluetooth: Read encryption key size for BR/EDR connections
Since Bluetooth 3.0 there's a HCI command available for reading the
encryption key size of an BR/EDR connection. This information is
essential e.g. for generating an LTK using SMP over BR/EDR, so store
it as part of struct hci_conn.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
-rw-r--r-- | include/net/bluetooth/hci.h | 10 | ||||
-rw-r--r-- | net/bluetooth/hci_event.c | 87 |
2 files changed, 97 insertions, 0 deletions
diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index d95da83..7ca6690 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -1202,6 +1202,16 @@ struct hci_rp_read_clock { __le16 accuracy; } __packed; +#define HCI_OP_READ_ENC_KEY_SIZE 0x1408 +struct hci_cp_read_enc_key_size { + __le16 handle; +} __packed; +struct hci_rp_read_enc_key_size { + __u8 status; + __le16 handle; + __u8 key_size; +} __packed; + #define HCI_OP_READ_LOCAL_AMP_INFO 0x1409 struct hci_rp_read_local_amp_info { __u8 status; diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 6293415..88c57b1 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -2603,6 +2603,64 @@ unlock: hci_dev_unlock(hdev); } +static void read_enc_key_size_complete(struct hci_dev *hdev, u8 status, + u16 opcode, struct sk_buff *skb) +{ + const struct hci_rp_read_enc_key_size *rp; + struct hci_conn *conn; + u16 handle; + + BT_DBG("%s status 0x%02x", hdev->name, status); + + if (!skb || skb->len < sizeof(*rp)) { + BT_ERR("%s invalid HCI Read Encryption Key Size response", + hdev->name); + return; + } + + rp = (void *)skb->data; + handle = le16_to_cpu(rp->handle); + + hci_dev_lock(hdev); + + conn = hci_conn_hash_lookup_handle(hdev, handle); + if (!conn) + goto unlock; + + /* If we fail to read the encryption key size, assume maximum + * (which is the same we do also when this HCI command isn't + * supported. + */ + if (rp->status) { + BT_ERR("%s failed to read key size for handle %u", hdev->name, + handle); + conn->enc_key_size = HCI_LINK_KEY_SIZE; + } else { + conn->enc_key_size = rp->key_size; + } + + if (conn->state == BT_CONFIG) { + conn->state = BT_CONNECTED; + hci_connect_cfm(conn, 0); + hci_conn_drop(conn); + } else { + u8 encrypt; + + if (!test_bit(HCI_CONN_ENCRYPT, &conn->flags)) + encrypt = 0x00; + else if (conn->type == ACL_LINK && + test_bit(HCI_CONN_AES_CCM, &conn->flags)) + encrypt = 0x02; + else + encrypt = 0x01; + + hci_encrypt_cfm(conn, 0, encrypt); + } + +unlock: + hci_dev_unlock(hdev); +} + static void hci_encrypt_change_evt(struct hci_dev *hdev, struct sk_buff *skb) { struct hci_ev_encrypt_change *ev = (void *) skb->data; @@ -2662,6 +2720,35 @@ static void hci_encrypt_change_evt(struct hci_dev *hdev, struct sk_buff *skb) goto unlock; } + /* Try reading the encryption key size for encrypted ACL links */ + if (!ev->status && ev->encrypt && conn->type == ACL_LINK) { + struct hci_cp_read_enc_key_size cp; + struct hci_request req; + + /* Only send HCI_Read_Encryption_Key_Size if the + * controller really supports it. If it doesn't, assume + * the default size (16). + */ + if (!(hdev->commands[20] & 0x10)) { + conn->enc_key_size = HCI_LINK_KEY_SIZE; + goto notify; + } + + hci_req_init(&req, hdev); + + cp.handle = cpu_to_le16(conn->handle); + hci_req_add(&req, HCI_OP_READ_ENC_KEY_SIZE, sizeof(cp), &cp); + + if (hci_req_run_skb(&req, read_enc_key_size_complete)) { + BT_ERR("Sending HCI Read Encryption Key Size failed"); + conn->enc_key_size = HCI_LINK_KEY_SIZE; + goto notify; + } + + goto unlock; + } + +notify: if (conn->state == BT_CONFIG) { if (!ev->status) conn->state = BT_CONNECTED; |