summaryrefslogtreecommitdiffstats
path: root/net/bluetooth/eir.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/bluetooth/eir.c')
-rw-r--r--net/bluetooth/eir.c398
1 files changed, 398 insertions, 0 deletions
diff --git a/net/bluetooth/eir.c b/net/bluetooth/eir.c
new file mode 100644
index 0000000000..9214189279
--- /dev/null
+++ b/net/bluetooth/eir.c
@@ -0,0 +1,398 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * BlueZ - Bluetooth protocol stack for Linux
+ *
+ * Copyright (C) 2021 Intel Corporation
+ */
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/mgmt.h>
+
+#include "eir.h"
+
+#define PNP_INFO_SVCLASS_ID 0x1200
+
+static u8 eir_append_name(u8 *eir, u16 eir_len, u8 type, u8 *data, u8 data_len)
+{
+ u8 name[HCI_MAX_SHORT_NAME_LENGTH + 1];
+
+ /* If data is already NULL terminated just pass it directly */
+ if (data[data_len - 1] == '\0')
+ return eir_append_data(eir, eir_len, type, data, data_len);
+
+ memcpy(name, data, HCI_MAX_SHORT_NAME_LENGTH);
+ name[HCI_MAX_SHORT_NAME_LENGTH] = '\0';
+
+ return eir_append_data(eir, eir_len, type, name, sizeof(name));
+}
+
+u8 eir_append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
+{
+ size_t short_len;
+ size_t complete_len;
+
+ /* no space left for name (+ NULL + type + len) */
+ if ((max_adv_len(hdev) - ad_len) < HCI_MAX_SHORT_NAME_LENGTH + 3)
+ return ad_len;
+
+ /* use complete name if present and fits */
+ complete_len = strnlen(hdev->dev_name, sizeof(hdev->dev_name));
+ if (complete_len && complete_len <= HCI_MAX_SHORT_NAME_LENGTH)
+ return eir_append_name(ptr, ad_len, EIR_NAME_COMPLETE,
+ hdev->dev_name, complete_len + 1);
+
+ /* use short name if present */
+ short_len = strnlen(hdev->short_name, sizeof(hdev->short_name));
+ if (short_len)
+ return eir_append_name(ptr, ad_len, EIR_NAME_SHORT,
+ hdev->short_name,
+ short_len == HCI_MAX_SHORT_NAME_LENGTH ?
+ short_len : short_len + 1);
+
+ /* use shortened full name if present, we already know that name
+ * is longer then HCI_MAX_SHORT_NAME_LENGTH
+ */
+ if (complete_len)
+ return eir_append_name(ptr, ad_len, EIR_NAME_SHORT,
+ hdev->dev_name,
+ HCI_MAX_SHORT_NAME_LENGTH);
+
+ return ad_len;
+}
+
+u8 eir_append_appearance(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
+{
+ return eir_append_le16(ptr, ad_len, EIR_APPEARANCE, hdev->appearance);
+}
+
+u8 eir_append_service_data(u8 *eir, u16 eir_len, u16 uuid, u8 *data,
+ u8 data_len)
+{
+ eir[eir_len++] = sizeof(u8) + sizeof(uuid) + data_len;
+ eir[eir_len++] = EIR_SERVICE_DATA;
+ put_unaligned_le16(uuid, &eir[eir_len]);
+ eir_len += sizeof(uuid);
+ memcpy(&eir[eir_len], data, data_len);
+ eir_len += data_len;
+
+ return eir_len;
+}
+
+static u8 *create_uuid16_list(struct hci_dev *hdev, u8 *data, ptrdiff_t len)
+{
+ u8 *ptr = data, *uuids_start = NULL;
+ struct bt_uuid *uuid;
+
+ if (len < 4)
+ return ptr;
+
+ list_for_each_entry(uuid, &hdev->uuids, list) {
+ u16 uuid16;
+
+ if (uuid->size != 16)
+ continue;
+
+ uuid16 = get_unaligned_le16(&uuid->uuid[12]);
+ if (uuid16 < 0x1100)
+ continue;
+
+ if (uuid16 == PNP_INFO_SVCLASS_ID)
+ continue;
+
+ if (!uuids_start) {
+ uuids_start = ptr;
+ uuids_start[0] = 1;
+ uuids_start[1] = EIR_UUID16_ALL;
+ ptr += 2;
+ }
+
+ /* Stop if not enough space to put next UUID */
+ if ((ptr - data) + sizeof(u16) > len) {
+ uuids_start[1] = EIR_UUID16_SOME;
+ break;
+ }
+
+ *ptr++ = (uuid16 & 0x00ff);
+ *ptr++ = (uuid16 & 0xff00) >> 8;
+ uuids_start[0] += sizeof(uuid16);
+ }
+
+ return ptr;
+}
+
+static u8 *create_uuid32_list(struct hci_dev *hdev, u8 *data, ptrdiff_t len)
+{
+ u8 *ptr = data, *uuids_start = NULL;
+ struct bt_uuid *uuid;
+
+ if (len < 6)
+ return ptr;
+
+ list_for_each_entry(uuid, &hdev->uuids, list) {
+ if (uuid->size != 32)
+ continue;
+
+ if (!uuids_start) {
+ uuids_start = ptr;
+ uuids_start[0] = 1;
+ uuids_start[1] = EIR_UUID32_ALL;
+ ptr += 2;
+ }
+
+ /* Stop if not enough space to put next UUID */
+ if ((ptr - data) + sizeof(u32) > len) {
+ uuids_start[1] = EIR_UUID32_SOME;
+ break;
+ }
+
+ memcpy(ptr, &uuid->uuid[12], sizeof(u32));
+ ptr += sizeof(u32);
+ uuids_start[0] += sizeof(u32);
+ }
+
+ return ptr;
+}
+
+static u8 *create_uuid128_list(struct hci_dev *hdev, u8 *data, ptrdiff_t len)
+{
+ u8 *ptr = data, *uuids_start = NULL;
+ struct bt_uuid *uuid;
+
+ if (len < 18)
+ return ptr;
+
+ list_for_each_entry(uuid, &hdev->uuids, list) {
+ if (uuid->size != 128)
+ continue;
+
+ if (!uuids_start) {
+ uuids_start = ptr;
+ uuids_start[0] = 1;
+ uuids_start[1] = EIR_UUID128_ALL;
+ ptr += 2;
+ }
+
+ /* Stop if not enough space to put next UUID */
+ if ((ptr - data) + 16 > len) {
+ uuids_start[1] = EIR_UUID128_SOME;
+ break;
+ }
+
+ memcpy(ptr, uuid->uuid, 16);
+ ptr += 16;
+ uuids_start[0] += 16;
+ }
+
+ return ptr;
+}
+
+void eir_create(struct hci_dev *hdev, u8 *data)
+{
+ u8 *ptr = data;
+ size_t name_len;
+
+ name_len = strnlen(hdev->dev_name, sizeof(hdev->dev_name));
+
+ if (name_len > 0) {
+ /* EIR Data type */
+ if (name_len > 48) {
+ name_len = 48;
+ ptr[1] = EIR_NAME_SHORT;
+ } else {
+ ptr[1] = EIR_NAME_COMPLETE;
+ }
+
+ /* EIR Data length */
+ ptr[0] = name_len + 1;
+
+ memcpy(ptr + 2, hdev->dev_name, name_len);
+
+ ptr += (name_len + 2);
+ }
+
+ if (hdev->inq_tx_power != HCI_TX_POWER_INVALID) {
+ ptr[0] = 2;
+ ptr[1] = EIR_TX_POWER;
+ ptr[2] = (u8)hdev->inq_tx_power;
+
+ ptr += 3;
+ }
+
+ if (hdev->devid_source > 0) {
+ ptr[0] = 9;
+ ptr[1] = EIR_DEVICE_ID;
+
+ put_unaligned_le16(hdev->devid_source, ptr + 2);
+ put_unaligned_le16(hdev->devid_vendor, ptr + 4);
+ put_unaligned_le16(hdev->devid_product, ptr + 6);
+ put_unaligned_le16(hdev->devid_version, ptr + 8);
+
+ ptr += 10;
+ }
+
+ ptr = create_uuid16_list(hdev, ptr, HCI_MAX_EIR_LENGTH - (ptr - data));
+ ptr = create_uuid32_list(hdev, ptr, HCI_MAX_EIR_LENGTH - (ptr - data));
+ ptr = create_uuid128_list(hdev, ptr, HCI_MAX_EIR_LENGTH - (ptr - data));
+}
+
+u8 eir_create_per_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr)
+{
+ struct adv_info *adv = NULL;
+ u8 ad_len = 0;
+
+ /* Return 0 when the current instance identifier is invalid. */
+ if (instance) {
+ adv = hci_find_adv_instance(hdev, instance);
+ if (!adv)
+ return 0;
+ }
+
+ if (adv) {
+ memcpy(ptr, adv->per_adv_data, adv->per_adv_data_len);
+ ad_len += adv->per_adv_data_len;
+ ptr += adv->per_adv_data_len;
+ }
+
+ return ad_len;
+}
+
+u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr)
+{
+ struct adv_info *adv = NULL;
+ u8 ad_len = 0, flags = 0;
+ u32 instance_flags;
+
+ /* Return 0 when the current instance identifier is invalid. */
+ if (instance) {
+ adv = hci_find_adv_instance(hdev, instance);
+ if (!adv)
+ return 0;
+ }
+
+ instance_flags = hci_adv_instance_flags(hdev, instance);
+
+ /* If instance already has the flags set skip adding it once
+ * again.
+ */
+ if (adv && eir_get_data(adv->adv_data, adv->adv_data_len, EIR_FLAGS,
+ NULL))
+ goto skip_flags;
+
+ /* The Add Advertising command allows userspace to set both the general
+ * and limited discoverable flags.
+ */
+ if (instance_flags & MGMT_ADV_FLAG_DISCOV)
+ flags |= LE_AD_GENERAL;
+
+ if (instance_flags & MGMT_ADV_FLAG_LIMITED_DISCOV)
+ flags |= LE_AD_LIMITED;
+
+ if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED))
+ flags |= LE_AD_NO_BREDR;
+
+ if (flags || (instance_flags & MGMT_ADV_FLAG_MANAGED_FLAGS)) {
+ /* If a discovery flag wasn't provided, simply use the global
+ * settings.
+ */
+ if (!flags)
+ flags |= mgmt_get_adv_discov_flags(hdev);
+
+ /* If flags would still be empty, then there is no need to
+ * include the "Flags" AD field".
+ */
+ if (flags) {
+ ptr[0] = 0x02;
+ ptr[1] = EIR_FLAGS;
+ ptr[2] = flags;
+
+ ad_len += 3;
+ ptr += 3;
+ }
+ }
+
+skip_flags:
+ if (adv) {
+ memcpy(ptr, adv->adv_data, adv->adv_data_len);
+ ad_len += adv->adv_data_len;
+ ptr += adv->adv_data_len;
+ }
+
+ if (instance_flags & MGMT_ADV_FLAG_TX_POWER) {
+ s8 adv_tx_power;
+
+ if (ext_adv_capable(hdev)) {
+ if (adv)
+ adv_tx_power = adv->tx_power;
+ else
+ adv_tx_power = hdev->adv_tx_power;
+ } else {
+ adv_tx_power = hdev->adv_tx_power;
+ }
+
+ /* Provide Tx Power only if we can provide a valid value for it */
+ if (adv_tx_power != HCI_TX_POWER_INVALID) {
+ ptr[0] = 0x02;
+ ptr[1] = EIR_TX_POWER;
+ ptr[2] = (u8)adv_tx_power;
+
+ ad_len += 3;
+ ptr += 3;
+ }
+ }
+
+ return ad_len;
+}
+
+static u8 create_default_scan_rsp(struct hci_dev *hdev, u8 *ptr)
+{
+ u8 scan_rsp_len = 0;
+
+ if (hdev->appearance)
+ scan_rsp_len = eir_append_appearance(hdev, ptr, scan_rsp_len);
+
+ return eir_append_local_name(hdev, ptr, scan_rsp_len);
+}
+
+u8 eir_create_scan_rsp(struct hci_dev *hdev, u8 instance, u8 *ptr)
+{
+ struct adv_info *adv;
+ u8 scan_rsp_len = 0;
+
+ if (!instance)
+ return create_default_scan_rsp(hdev, ptr);
+
+ adv = hci_find_adv_instance(hdev, instance);
+ if (!adv)
+ return 0;
+
+ if ((adv->flags & MGMT_ADV_FLAG_APPEARANCE) && hdev->appearance)
+ scan_rsp_len = eir_append_appearance(hdev, ptr, scan_rsp_len);
+
+ memcpy(&ptr[scan_rsp_len], adv->scan_rsp_data, adv->scan_rsp_len);
+
+ scan_rsp_len += adv->scan_rsp_len;
+
+ if (adv->flags & MGMT_ADV_FLAG_LOCAL_NAME)
+ scan_rsp_len = eir_append_local_name(hdev, ptr, scan_rsp_len);
+
+ return scan_rsp_len;
+}
+
+void *eir_get_service_data(u8 *eir, size_t eir_len, u16 uuid, size_t *len)
+{
+ while ((eir = eir_get_data(eir, eir_len, EIR_SERVICE_DATA, len))) {
+ u16 value = get_unaligned_le16(eir);
+
+ if (uuid == value) {
+ if (len)
+ *len -= 2;
+ return &eir[2];
+ }
+
+ eir += *len;
+ eir_len -= *len;
+ }
+
+ return NULL;
+}