2019-08-30 08:03:13

by K, SpoorthiX

Subject: [PATCH] Add Support to use Resolving list

From: Spoorthi Ravishankar Koppad <[email protected]>

As per Core specification 5.0, Vol 2, Part E, Section 7.8.38,
following code changes implements LE add device to Resolving List.

Signed-off-by: Spoorthi Ravishankar Koppad <[email protected]>
---
include/net/bluetooth/hci.h | 1 +
net/bluetooth/hci_request.c | 74 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 75 insertions(+)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index c36dc1e..99a38cf36 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -420,6 +420,7 @@ enum {
#define HCI_LE_SLAVE_FEATURES 0x08
#define HCI_LE_PING 0x10
#define HCI_LE_DATA_LEN_EXT 0x20
+#define HCI_LE_LL_PRIVACY 0x40
#define HCI_LE_PHY_2M 0x01
#define HCI_LE_PHY_CODED 0x08
#define HCI_LE_EXT_ADV 0x10
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index ca73d36..37ee023 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -665,6 +665,72 @@ void hci_req_add_le_scan_disable(struct hci_request *req)
}
}

+static void add_to_resolve_list(struct hci_request *req,
+ struct hci_conn_params *params)
+{
+ struct hci_cp_le_add_to_resolv_list cp;
+ struct bdaddr_list_with_irk *entry;
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return;
+
+ memset(&cp, 0, sizeof(cp));
+
+ cp.bdaddr_type = params->addr_type;
+ bacpy(&cp.bdaddr, &params->addr);
+ memcpy(entry->peer_irk, cp.peer_irk, 16);
+ memcpy(entry->local_irk, cp.local_irk, 16);
+
+ hci_req_add(req, HCI_OP_LE_ADD_TO_RESOLV_LIST, sizeof(cp), &cp);
+}
+
+static void update_resolve_list(struct hci_request *req)
+{
+ struct hci_dev *hdev = req->hdev;
+ struct hci_conn_params *params;
+ int err;
+ u8 resolve_list_entries = 0;
+
+ list_for_each_entry(params, &hdev->le_resolv_list, action) {
+ /* Cannot Remove or add the device to the Resolving list
+ * whenever there is an outstanding connection.
+ */
+ if (!hci_pend_le_action_lookup(&hdev->pend_le_conns,
+ &params->addr,
+ params->addr_type) &&
+ !hci_pend_le_action_lookup(&hdev->pend_le_reports,
+ &params->addr,
+ params->addr_type)) {
+ struct hci_cp_le_del_from_resolv_list cp;
+
+ cp.bdaddr_type = params->addr_type;
+ bacpy(&cp.bdaddr, &params->addr);
+
+ hci_req_add(req, HCI_OP_LE_DEL_FROM_RESOLV_LIST,
+ sizeof(cp), &cp);
+ continue;
+ }
+ if (hci_bdaddr_list_lookup(&hdev->le_resolv_list,
+ &params->addr, params->addr_type))
+ continue;
+
+ if (hci_find_irk_by_addr(hdev, &params->addr,
+ params->addr_type)) {
+ /* Add device to resolving list */
+ resolve_list_entries++;
+ add_to_resolve_list(req, params);
+ }
+ if (resolve_list_entries >= hdev->le_resolv_list_size) {
+ err = smp_generate_rpa(hdev, hdev->irk, &hdev->rpa);
+ if (err < 0)
+ BT_ERR("%s failed to generate new RPA",
+ hdev->name);
+ }
+ resolve_list_entries++;
+ }
+}
+
static void add_to_white_list(struct hci_request *req,
struct hci_conn_params *params)
{
@@ -891,6 +957,14 @@ void hci_req_add_le_passive_scan(struct hci_request *req)
(hdev->le_features[0] & HCI_LE_EXT_SCAN_POLICY))
filter_policy |= 0x02;

+ /* When filter policy is not 0x00 (no whitelist) and 0x01
+ * (whitelist enabled) and if LE Privacy is supported in controller
+ * add the device to resolving list.
+ */
+ if ((filter_policy == 0x02 || filter_policy == 0x03) &&
+ (hci_dev_test_flag(hdev, HCI_LE_LL_PRIVACY)))
+ update_resolve_list(req);
+
hci_req_start_scan(req, LE_SCAN_PASSIVE, hdev->le_scan_interval,
hdev->le_scan_window, own_addr_type, filter_policy);
}
--
1.9.1

2019-09-05 18:48:23

by Marcel Holtmann

Subject: Re: [PATCH] Add Support to use Resolving list

Hi Spoorthi,

> As per Core specification 5.0, Vol 2, Part E, Section 7.8.38,
> following code changes implements LE add device to Resolving List.
>
> Signed-off-by: Spoorthi Ravishankar Koppad <[email protected]>
> ---
> include/net/bluetooth/hci.h | 1 +
> net/bluetooth/hci_request.c | 74 +++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 75 insertions(+)
>
> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> index c36dc1e..99a38cf36 100644
> --- a/include/net/bluetooth/hci.h
> +++ b/include/net/bluetooth/hci.h
> @@ -420,6 +420,7 @@ enum {
> #define HCI_LE_SLAVE_FEATURES 0x08
> #define HCI_LE_PING 0x10
> #define HCI_LE_DATA_LEN_EXT 0x20
> +#define HCI_LE_LL_PRIVACY 0x40
> #define HCI_LE_PHY_2M 0x01
> #define HCI_LE_PHY_CODED 0x08
> #define HCI_LE_EXT_ADV 0x10
> diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
> index ca73d36..37ee023 100644
> --- a/net/bluetooth/hci_request.c
> +++ b/net/bluetooth/hci_request.c
> @@ -665,6 +665,72 @@ void hci_req_add_le_scan_disable(struct hci_request *req)
> }
> }
>
> +static void add_to_resolve_list(struct hci_request *req,
> + struct hci_conn_params *params)
> +{
> + struct hci_cp_le_add_to_resolv_list cp;
> + struct bdaddr_list_with_irk *entry;
> +
> + entry = kzalloc(sizeof(*entry), GFP_KERNEL);
> + if (!entry)
> + return;
> +
> + memset(&cp, 0, sizeof(cp));
> +
> + cp.bdaddr_type = params->addr_type;
> + bacpy(&cp.bdaddr, &params->addr);
> + memcpy(entry->peer_irk, cp.peer_irk, 16);
> + memcpy(entry->local_irk, cp.local_irk, 16);
> +
> + hci_req_add(req, HCI_OP_LE_ADD_TO_RESOLV_LIST, sizeof(cp), &cp);
> +}
> +
> +static void update_resolve_list(struct hci_request *req)
> +{
> + struct hci_dev *hdev = req->hdev;
> + struct hci_conn_params *params;
> + int err;
> + u8 resolve_list_entries = 0;
> +
> + list_for_each_entry(params, &hdev->le_resolv_list, action) {
> + /* Cannot Remove or add the device to the Resolving list
> + * whenever there is an outstanding connection.
> + */
> + if (!hci_pend_le_action_lookup(&hdev->pend_le_conns,
> + &params->addr,
> + params->addr_type) &&
> + !hci_pend_le_action_lookup(&hdev->pend_le_reports,
> + &params->addr,
> + params->addr_type)) {
> + struct hci_cp_le_del_from_resolv_list cp;
> +
> + cp.bdaddr_type = params->addr_type;
> + bacpy(&cp.bdaddr, &params->addr);
> +
> + hci_req_add(req, HCI_OP_LE_DEL_FROM_RESOLV_LIST,
> + sizeof(cp), &cp);
> + continue;
> + }

I do not understand this logic. The device gets removed and then you move on to the next one?

> + if (hci_bdaddr_list_lookup(&hdev->le_resolv_list,
> + &params->addr, params->addr_type))
> + continue;

What is this good for?

> +
> + if (hci_find_irk_by_addr(hdev, &params->addr,
> + params->addr_type)) {
> + /* Add device to resolving list */
> + resolve_list_entries++;
> + add_to_resolve_list(req, params);
> + }
> + if (resolve_list_entries >= hdev->le_resolv_list_size) {
> + err = smp_generate_rpa(hdev, hdev->irk, &hdev->rpa);
> + if (err < 0)
> + BT_ERR("%s failed to generate new RPA",
> + hdev->name);
> + }

Wh are you doing this?

> + resolve_list_entries++;
> + }
> +}
> +
> static void add_to_white_list(struct hci_request *req,
> struct hci_conn_params *params)
> {
> @@ -891,6 +957,14 @@ void hci_req_add_le_passive_scan(struct hci_request *req)
> (hdev->le_features[0] & HCI_LE_EXT_SCAN_POLICY))
> filter_policy |= 0x02;
>
> + /* When filter policy is not 0x00 (no whitelist) and 0x01
> + * (whitelist enabled) and if LE Privacy is supported in controller
> + * add the device to resolving list.
> + */
> + if ((filter_policy == 0x02 || filter_policy == 0x03) &&
> + (hci_dev_test_flag(hdev, HCI_LE_LL_PRIVACY)))
> + update_resolve_list(req);
> +

I do not understand this logic. The resolving list has really nothing to do with the whitelist. Even for active scan we want to use the resolving list for known devices. I mean yes, in theory we could resolve all RPAs in the host during active scan / discovery, but is that really something we want.

> hci_req_start_scan(req, LE_SCAN_PASSIVE, hdev->le_scan_interval,
> hdev->le_scan_window, own_addr_type, filter_policy);
> }

Regards

Marcel