Bluetooth: Split hci_request helpers to hci_request.[ch]

None of the hci_request related things in net/bluetooth/hci_core.h are
needed anywhere outside of the core bluetooth module. This patch creates
a new net/bluetooth/hci_request.c file with its corresponding h-file and
moves the functionality there from hci_core.c and hci_core.h.

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

1 files changed, 397 insertions, 0 deletions

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
new file mode 100644
index 000000000000..eba83a2a6556
--- /dev/null
+++ b/net/bluetooth/hci_request.c
@@ -0,0 +1,397 @@
+/*
+   BlueZ - Bluetooth protocol stack for Linux
+
+   Copyright (C) 2014 Intel Corporation
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License version 2 as
+   published by the Free Software Foundation;
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
+   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
+   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
+   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
+   SOFTWARE IS DISCLAIMED.
+*/
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#include "smp.h"
+#include "hci_request.h"
+
+void hci_req_init(struct hci_request *req, struct hci_dev *hdev)
+{
+        skb_queue_head_init(&req->cmd_q);
+        req->hdev = hdev;
+        req->err = 0;
+}
+
+int hci_req_run(struct hci_request *req, hci_req_complete_t complete)
+{
+        struct hci_dev *hdev = req->hdev;
+        struct sk_buff *skb;
+        unsigned long flags;
+
+        BT_DBG("length %u", skb_queue_len(&req->cmd_q));
+
+        /* If an error occurred during request building, remove all HCI
+         * commands queued on the HCI request queue.
+         */
+        if (req->err) {
+                skb_queue_purge(&req->cmd_q);
+                return req->err;
+        }
+
+        /* Do not allow empty requests */
+        if (skb_queue_empty(&req->cmd_q))
+                return -ENODATA;
+
+        skb = skb_peek_tail(&req->cmd_q);
+        bt_cb(skb)->req.complete = complete;
+
+        spin_lock_irqsave(&hdev->cmd_q.lock, flags);
+        skb_queue_splice_tail(&req->cmd_q, &hdev->cmd_q);
+        spin_unlock_irqrestore(&hdev->cmd_q.lock, flags);
+
+        queue_work(hdev->workqueue, &hdev->cmd_work);
+
+        return 0;
+}
+
+struct sk_buff *hci_prepare_cmd(struct hci_dev *hdev, u16 opcode, u32 plen,
+                                const void *param)
+{
+        int len = HCI_COMMAND_HDR_SIZE + plen;
+        struct hci_command_hdr *hdr;
+        struct sk_buff *skb;
+
+        skb = bt_skb_alloc(len, GFP_ATOMIC);
+        if (!skb)
+                return NULL;
+
+        hdr = (struct hci_command_hdr *) skb_put(skb, HCI_COMMAND_HDR_SIZE);
+        hdr->opcode = cpu_to_le16(opcode);
+        hdr->plen   = plen;
+
+        if (plen)
+                memcpy(skb_put(skb, plen), param, plen);
+
+        BT_DBG("skb len %d", skb->len);
+
+        bt_cb(skb)->pkt_type = HCI_COMMAND_PKT;
+        bt_cb(skb)->opcode = opcode;
+
+        return skb;
+}
+
+/* Queue a command to an asynchronous HCI request */
+void hci_req_add_ev(struct hci_request *req, u16 opcode, u32 plen,
+                    const void *param, u8 event)
+{
+        struct hci_dev *hdev = req->hdev;
+        struct sk_buff *skb;
+
+        BT_DBG("%s opcode 0x%4.4x plen %d", hdev->name, opcode, plen);
+
+        /* If an error occurred during request building, there is no point in
+         * queueing the HCI command. We can simply return.
+         */
+        if (req->err)
+                return;
+
+        skb = hci_prepare_cmd(hdev, opcode, plen, param);
+        if (!skb) {
+                BT_ERR("%s no memory for command (opcode 0x%4.4x)",
+                       hdev->name, opcode);
+                req->err = -ENOMEM;
+                return;
+        }
+
+        if (skb_queue_empty(&req->cmd_q))
+                bt_cb(skb)->req.start = true;
+
+        bt_cb(skb)->req.event = event;
+
+        skb_queue_tail(&req->cmd_q, skb);
+}
+
+void hci_req_add(struct hci_request *req, u16 opcode, u32 plen,
+                 const void *param)
+{
+        hci_req_add_ev(req, opcode, plen, param, 0);
+}
+
+void hci_req_add_le_scan_disable(struct hci_request *req)
+{
+        struct hci_cp_le_set_scan_enable cp;
+
+        memset(&cp, 0, sizeof(cp));
+        cp.enable = LE_SCAN_DISABLE;
+        hci_req_add(req, HCI_OP_LE_SET_SCAN_ENABLE, sizeof(cp), &cp);
+}
+
+static void add_to_white_list(struct hci_request *req,
+                              struct hci_conn_params *params)
+{
+        struct hci_cp_le_add_to_white_list cp;
+
+        cp.bdaddr_type = params->addr_type;
+        bacpy(&cp.bdaddr, &params->addr);
+
+        hci_req_add(req, HCI_OP_LE_ADD_TO_WHITE_LIST, sizeof(cp), &cp);
+}
+
+static u8 update_white_list(struct hci_request *req)
+{
+        struct hci_dev *hdev = req->hdev;
+        struct hci_conn_params *params;
+        struct bdaddr_list *b;
+        uint8_t white_list_entries = 0;
+
+        /* Go through the current white list programmed into the
+         * controller one by one and check if that address is still
+         * in the list of pending connections or list of devices to
+         * report. If not present in either list, then queue the
+         * command to remove it from the controller.
+         */
+        list_for_each_entry(b, &hdev->le_white_list, list) {
+                struct hci_cp_le_del_from_white_list cp;
+
+                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)) {
+                        white_list_entries++;
+                        continue;
+                }
+
+                cp.bdaddr_type = b->bdaddr_type;
+                bacpy(&cp.bdaddr, &b->bdaddr);
+
+                hci_req_add(req, HCI_OP_LE_DEL_FROM_WHITE_LIST,
+                            sizeof(cp), &cp);
+        }
+
+        /* Since all no longer valid white list entries have been
+         * removed, walk through the list of pending connections
+         * and ensure that any new device gets programmed into
+         * the controller.
+         *
+         * If the list of the devices is larger than the list of
+         * available white list entries in the controller, then
+         * just abort and return filer policy value to not use the
+         * white list.
+         */
+        list_for_each_entry(params, &hdev->pend_le_conns, action) {
+                if (hci_bdaddr_list_lookup(&hdev->le_white_list,
+                                           &params->addr, params->addr_type))
+                        continue;
+
+                if (white_list_entries >= hdev->le_white_list_size) {
+                        /* Select filter policy to accept all advertising */
+                        return 0x00;
+                }
+
+                if (hci_find_irk_by_addr(hdev, &params->addr,
+                                         params->addr_type)) {
+                        /* White list can not be used with RPAs */
+                        return 0x00;
+                }
+
+                white_list_entries++;
+                add_to_white_list(req, params);
+        }
+
+        /* After adding all new pending connections, walk through
+         * the list of pending reports and also add these to the
+         * white list if there is still space.
+         */
+        list_for_each_entry(params, &hdev->pend_le_reports, action) {
+                if (hci_bdaddr_list_lookup(&hdev->le_white_list,
+                                           &params->addr, params->addr_type))
+                        continue;
+
+                if (white_list_entries >= hdev->le_white_list_size) {
+                        /* Select filter policy to accept all advertising */
+                        return 0x00;
+                }
+
+                if (hci_find_irk_by_addr(hdev, &params->addr,
+                                         params->addr_type)) {
+                        /* White list can not be used with RPAs */
+                        return 0x00;
+                }
+
+                white_list_entries++;
+                add_to_white_list(req, params);
+        }
+
+        /* Select filter policy to use white list */
+        return 0x01;
+}
+
+void hci_req_add_le_passive_scan(struct hci_request *req)
+{
+        struct hci_cp_le_set_scan_param param_cp;
+        struct hci_cp_le_set_scan_enable enable_cp;
+        struct hci_dev *hdev = req->hdev;
+        u8 own_addr_type;
+        u8 filter_policy;
+
+        /* Set require_privacy to false since no SCAN_REQ are send
+         * during passive scanning. Not using an non-resolvable address
+         * here is important so that peer devices using direct
+         * advertising with our address will be correctly reported
+         * by the controller.
+         */
+        if (hci_update_random_address(req, false, &own_addr_type))
+                return;
+
+        /* Adding or removing entries from the white list must
+         * happen before enabling scanning. The controller does
+         * not allow white list modification while scanning.
+         */
+        filter_policy = update_white_list(req);
+
+        /* When the controller is using random resolvable addresses and
+         * with that having LE privacy enabled, then controllers with
+         * Extended Scanner Filter Policies support can now enable support
+         * for handling directed advertising.
+         *
+         * So instead of using filter polices 0x00 (no whitelist)
+         * and 0x01 (whitelist enabled) use the new filter policies
+         * 0x02 (no whitelist) and 0x03 (whitelist enabled).
+         */
+        if (test_bit(HCI_PRIVACY, &hdev->dev_flags) &&
+            (hdev->le_features[0] & HCI_LE_EXT_SCAN_POLICY))
+                filter_policy |= 0x02;
+
+        memset(&param_cp, 0, sizeof(param_cp));
+        param_cp.type = LE_SCAN_PASSIVE;
+        param_cp.interval = cpu_to_le16(hdev->le_scan_interval);
+        param_cp.window = cpu_to_le16(hdev->le_scan_window);
+        param_cp.own_address_type = own_addr_type;
+        param_cp.filter_policy = filter_policy;
+        hci_req_add(req, HCI_OP_LE_SET_SCAN_PARAM, sizeof(param_cp),
+                    &param_cp);
+
+        memset(&enable_cp, 0, sizeof(enable_cp));
+        enable_cp.enable = LE_SCAN_ENABLE;
+        enable_cp.filter_dup = LE_SCAN_FILTER_DUP_ENABLE;
+        hci_req_add(req, HCI_OP_LE_SET_SCAN_ENABLE, sizeof(enable_cp),
+                    &enable_cp);
+}
+
+static void set_random_addr(struct hci_request *req, bdaddr_t *rpa)
+{
+        struct hci_dev *hdev = req->hdev;
+
+        /* If we're advertising or initiating an LE connection we can't
+         * go ahead and change the random address at this time. This is
+         * because the eventual initiator address used for the
+         * subsequently created connection will be undefined (some
+         * controllers use the new address and others the one we had
+         * when the operation started).
+         *
+         * In this kind of scenario skip the update and let the random
+         * address be updated at the next cycle.
+         */
+        if (test_bit(HCI_LE_ADV, &hdev->dev_flags) ||
+            hci_conn_hash_lookup_state(hdev, LE_LINK, BT_CONNECT)) {
+                BT_DBG("Deferring random address update");
+                set_bit(HCI_RPA_EXPIRED, &hdev->dev_flags);
+                return;
+        }
+
+        hci_req_add(req, HCI_OP_LE_SET_RANDOM_ADDR, 6, rpa);
+}
+
+int hci_update_random_address(struct hci_request *req, bool require_privacy,
+                              u8 *own_addr_type)
+{
+        struct hci_dev *hdev = req->hdev;
+        int err;
+
+        /* If privacy is enabled use a resolvable private address. If
+         * current RPA has expired or there is something else than
+         * the current RPA in use, then generate a new one.
+         */
+        if (test_bit(HCI_PRIVACY, &hdev->dev_flags)) {
+                int to;
+
+                *own_addr_type = ADDR_LE_DEV_RANDOM;
+
+                if (!test_and_clear_bit(HCI_RPA_EXPIRED, &hdev->dev_flags) &&
+                    !bacmp(&hdev->random_addr, &hdev->rpa))
+                        return 0;
+
+                err = smp_generate_rpa(hdev, hdev->irk, &hdev->rpa);
+                if (err < 0) {
+                        BT_ERR("%s failed to generate new RPA", hdev->name);
+                        return err;
+                }
+
+                set_random_addr(req, &hdev->rpa);
+
+                to = msecs_to_jiffies(hdev->rpa_timeout * 1000);
+                queue_delayed_work(hdev->workqueue, &hdev->rpa_expired, to);
+
+                return 0;
+        }
+
+        /* In case of required privacy without resolvable private address,
+         * use an non-resolvable private address. This is useful for active
+         * scanning and non-connectable advertising.
+         */
+        if (require_privacy) {
+                bdaddr_t nrpa;
+
+                while (true) {
+                        /* The non-resolvable private address is generated
+                         * from random six bytes with the two most significant
+                         * bits cleared.
+                         */
+                        get_random_bytes(&nrpa, 6);
+                        nrpa.b[5] &= 0x3f;
+
+                        /* The non-resolvable private address shall not be
+                         * equal to the public address.
+                         */
+                        if (bacmp(&hdev->bdaddr, &nrpa))
+                                break;
+                }
+
+                *own_addr_type = ADDR_LE_DEV_RANDOM;
+                set_random_addr(req, &nrpa);
+                return 0;
+        }
+
+        /* If forcing static address is in use or there is no public
+         * address use the static address as random address (but skip
+         * the HCI command if the current random address is already the
+         * static one.
+         */
+        if (test_bit(HCI_FORCE_STATIC_ADDR, &hdev->dbg_flags) ||
+            !bacmp(&hdev->bdaddr, BDADDR_ANY)) {
+                *own_addr_type = ADDR_LE_DEV_RANDOM;
+                if (bacmp(&hdev->static_addr, &hdev->random_addr))
+                        hci_req_add(req, HCI_OP_LE_SET_RANDOM_ADDR, 6,
+                                    &hdev->static_addr);
+                return 0;
+        }
+
+        /* Neither privacy nor static address is being used so use a
+         * public address.
+         */
+        *own_addr_type = ADDR_LE_DEV_PUBLIC;
+
+        return 0;
+}