Return-Path: Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2102\)) Subject: Re: [PATCH v7 4/6] Bluetooth: advertisement handling in new connect procedure From: Marcel Holtmann In-Reply-To: <1438694299-5991-4-git-send-email-jpawlowski@google.com> Date: Tue, 4 Aug 2015 18:47:10 -0700 Cc: linux-bluetooth@vger.kernel.org Message-Id: <2D952E7F-7A09-4BA4-8E21-C21DA79611B4@holtmann.org> References: <1438694299-5991-1-git-send-email-jpawlowski@google.com> <1438694299-5991-4-git-send-email-jpawlowski@google.com> To: Jakub Pawlowski Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Jakub, > Currently, when trying to connect to already paired device that just > rotated its RPA MAC address, old address would be used and connection > would fail. In order to fix that, kernel must scan and receive > advertisement with fresh RPA before connecting. > > This path makes sure that after advertisement is received from device that > we try to connect to, it is properly handled in check_pending_le_conn and > trigger connect attempt. > > It also modifies hci_le_connect to make sure that connect attempt will be > properly continued. > > Signed-off-by: Jakub Pawlowski > --- > net/bluetooth/hci_conn.c | 48 ++++++++++++++++++++++++++++++-------------- > net/bluetooth/hci_event.c | 51 +++++++++++++++++++++++++++-------------------- > net/bluetooth/mgmt.c | 6 ++++++ > 3 files changed, 68 insertions(+), 37 deletions(-) > > diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c > index a74c636..64aaee3 100644 > --- a/net/bluetooth/hci_conn.c > +++ b/net/bluetooth/hci_conn.c > @@ -667,15 +667,18 @@ static void create_le_conn_complete(struct hci_dev *hdev, u8 status, u16 opcode) > { > struct hci_conn *conn; > > - if (status == 0) > - return; > + hci_dev_lock(hdev); > + > + conn = hci_lookup_le_connecting(hdev); > + > + if (status == 0) { Lets do if (!status) here if if the previous code did it differently. > + hci_connect_le_scan_cleanup(conn); > + goto done; > + } > > BT_ERR("HCI request failed to create LE connection: status 0x%2.2x", > status); > > - hci_dev_lock(hdev); > - > - conn = hci_lookup_le_connecting(hdev); > if (!conn) > goto done; > > @@ -715,6 +718,7 @@ static void hci_req_add_le_create_conn(struct hci_request *req, > hci_req_add(req, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp); > > conn->state = BT_CONNECT; > + clear_bit(HCI_CONN_SCANNING, &conn->flags); > } > > static void hci_req_directed_advertising(struct hci_request *req, > @@ -758,7 +762,7 @@ struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst, > u8 role) > { > struct hci_conn_params *params; > - struct hci_conn *conn; > + struct hci_conn *conn, *conn_unfinished; > struct smp_irk *irk; > struct hci_request req; > int err; > @@ -781,9 +785,17 @@ struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst, > * and return the object found. > */ > conn = hci_conn_hash_lookup_ba(hdev, LE_LINK, dst); > + conn_unfinished = NULL; > if (conn) { > - conn->pending_sec_level = sec_level; > - goto done; > + if (conn->state == BT_CONNECT && > + test_bit(HCI_CONN_SCANNING, &conn->flags)) { > + BT_DBG("will coninue unfinished conn %pMR", dst); Lets write "continue" correctly. > + conn_unfinished = conn; > + } else { > + if (conn->pending_sec_level < sec_level) > + conn->pending_sec_level = sec_level; > + goto done; > + } > } > > /* Since the controller supports only one LE connection attempt at a > @@ -796,10 +808,6 @@ struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst, > * resolving key, the connection needs to be established > * to a resolvable random address. > * > - * This uses the cached random resolvable address from > - * a previous scan. When no cached address is available, > - * try connecting to the identity address instead. > - * > * Storing the resolvable random address is required here > * to handle connection failures. The address will later > * be resolved back into the original identity address > @@ -811,15 +819,23 @@ struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst, > dst_type = ADDR_LE_DEV_RANDOM; > } > > - conn = hci_conn_add(hdev, LE_LINK, dst, role); > + if (conn_unfinished) { > + conn = conn_unfinished; > + bacpy(&conn->dst, dst); > + } else { > + conn = hci_conn_add(hdev, LE_LINK, dst, role); > + } > + > if (!conn) > return ERR_PTR(-ENOMEM); > > conn->dst_type = dst_type; > conn->sec_level = BT_SECURITY_LOW; > - conn->pending_sec_level = sec_level; > conn->conn_timeout = conn_timeout; > > + if (!conn_unfinished) > + conn->pending_sec_level = sec_level; > + > hci_req_init(&req, hdev); > > /* Disable advertising if we're active. For master role > @@ -884,7 +900,9 @@ create_conn: > } > > done: > - hci_conn_hold(conn); > + if (!conn_unfinished) > + hci_conn_hold(conn); > + This part I do not really like. Reference counting based o the point being valid is something I find terrible to debug later on. Why is this needed anyway? Don't we assign conn = conn_unfinished anyway? > return conn; > } > > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c > index 1859916..705c34f 100644 > --- a/net/bluetooth/hci_event.c > +++ b/net/bluetooth/hci_event.c > @@ -4640,42 +4640,49 @@ static struct hci_conn *check_pending_le_conn(struct hci_dev *hdev, > /* If we're not connectable only connect devices that we have in > * our pend_le_conns list. > */ > - params = hci_pend_le_action_lookup(&hdev->pend_le_conns, > - addr, addr_type); > + params = hci_explicit_connect_lookup(hdev, addr, addr_type); > + > if (!params) > return NULL; > > - switch (params->auto_connect) { > - case HCI_AUTO_CONN_DIRECT: > - /* Only devices advertising with ADV_DIRECT_IND are > - * triggering a connection attempt. This is allowing > - * incoming connections from slave devices. > - */ > - if (adv_type != LE_ADV_DIRECT_IND) > + if (!params->explicit_connect) { > + switch (params->auto_connect) { > + case HCI_AUTO_CONN_DIRECT: > + /* Only devices advertising with ADV_DIRECT_IND are > + * triggering a connection attempt. This is allowing > + * incoming connections from slave devices. > + */ > + if (adv_type != LE_ADV_DIRECT_IND) > + return NULL; > + break; > + case HCI_AUTO_CONN_ALWAYS: > + /* Devices advertising with ADV_IND or ADV_DIRECT_IND > + * are triggering a connection attempt. This means > + * that incoming connectioms from slave device are > + * accepted and also outgoing connections to slave > + * devices are established when found. > + */ > + break; > + default: > return NULL; > - break; > - case HCI_AUTO_CONN_ALWAYS: > - /* Devices advertising with ADV_IND or ADV_DIRECT_IND > - * are triggering a connection attempt. This means > - * that incoming connectioms from slave device are > - * accepted and also outgoing connections to slave > - * devices are established when found. > - */ > - break; > - default: > - return NULL; > + } > } > > conn = hci_connect_le(hdev, addr, addr_type, BT_SECURITY_LOW, > HCI_LE_AUTOCONN_TIMEOUT, HCI_ROLE_MASTER); > if (!IS_ERR(conn)) { > - /* Store the pointer since we don't really have any > + /* If HCI_AUTO_CONN_EXPLICIT is set, conn is already owned > + * by higher layer that tried to connect, if no then > + * store the pointer since we don't really have any > * other owner of the object besides the params that > * triggered it. This way we can abort the connection if > * the parameters get removed and keep the reference > * count consistent once the connection is established. > */ > - params->conn = hci_conn_get(conn); > + > + if (!params->explicit_connect) > + params->conn = hci_conn_get(conn); > + > return conn; > } > > diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c > index 0131866..af592eb 100644 > --- a/net/bluetooth/mgmt.c > +++ b/net/bluetooth/mgmt.c > @@ -6107,6 +6107,12 @@ static int hci_conn_params_set(struct hci_request *req, bdaddr_t *addr, > switch (auto_connect) { > case HCI_AUTO_CONN_DISABLED: > case HCI_AUTO_CONN_LINK_LOSS: > + /* If auto connect is being disabled when we're trying to > + * connect to device, keep connecting. > + */ > + if (params->explicit_connect) > + list_add(¶ms->action, &hdev->pend_le_conns); > + > __hci_update_background_scan(req); > break; > case HCI_AUTO_CONN_REPORT: Regards Marcel