From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Himanshu Rawat Date: Mon, 8 Apr 2024 19:42:21 +0000 Subject: [PATCH] Disallow unexpected incoming HID connections 1/2 HID profile accepted any new incoming HID connection. Even when the connection policy disabled HID connection, remote devices could initiate HID connection. This change ensures that incoming HID connection are accepted only if application was interested in that HID connection. This vulnerarbility no longer exists on the main because of feature request b/324093729. Test: Manual | Pair and connect a HID device, disable HID connection from Bluetooth device setting, attempt to connect from the HID device. Bug: 308429049 Ignore-AOSP-First: security (cherry picked from https://googleplex-android-review.googlesource.com/q/commit:18c635ad7923f5c26d6cd4cf7f7c66b2fa02462b) Merged-In: I6e9db983e752dd498625078c13b736cd4c668806 Change-Id: I6e9db983e752dd498625078c13b736cd4c668806 --- btif/include/btif_hh.h | 4 +- btif/include/btif_storage.h | 23 ++++++++++ btif/src/btif_hh.cc | 86 ++++++++++++++++++++++++++++++++++--- btif/src/btif_storage.cc | 53 ++++++++++++++++++++++- include/hardware/bt_hh.h | 2 +- 5 files changed, 160 insertions(+), 8 deletions(-) diff --git a/btif/include/btif_hh.h b/btif/include/btif_hh.h index 5c1ad4510..8c9ead462 100644 --- a/btif/include/btif_hh.h +++ b/btif/include/btif_hh.h @@ -94,6 +94,7 @@ typedef struct { uint8_t dev_handle; RawAddress bd_addr; tBTA_HH_ATTR_MASK attr_mask; + bool reconnect_allowed; } btif_hh_added_device_t; /** @@ -119,7 +120,8 @@ extern btif_hh_cb_t btif_hh_cb; extern btif_hh_device_t* btif_hh_find_connected_dev_by_handle(uint8_t handle); extern void btif_hh_remove_device(RawAddress bd_addr); extern bool btif_hh_add_added_dev(const RawAddress& bda, - tBTA_HH_ATTR_MASK attr_mask); + tBTA_HH_ATTR_MASK attr_mask, + bool reconnect_allowed); extern bt_status_t btif_hh_virtual_unplug(const RawAddress* bd_addr); extern void btif_hh_disconnect(RawAddress* bd_addr); extern void btif_hh_setreport(btif_hh_device_t* p_dev, diff --git a/btif/include/btif_storage.h b/btif/include/btif_storage.h index 07d29c81a..365f714d2 100644 --- a/btif/include/btif_storage.h +++ b/btif/include/btif_storage.h @@ -152,6 +152,29 @@ bt_status_t btif_storage_remove_bonded_device(const RawAddress* remote_bd_addr); ******************************************************************************/ bt_status_t btif_storage_load_bonded_devices(void); +/******************************************************************************* + * + * Function btif_storage_set_hid_connection_policy + * + * Description Stores connection policy info in nvram + * + * Returns BT_STATUS_SUCCESS + * + ******************************************************************************/ +bt_status_t btif_storage_set_hid_connection_policy(const RawAddress& addr, + bool reconnect_allowed); +/******************************************************************************* + * + * Function btif_storage_get_hid_connection_policy + * + * Description get connection policy info from nvram + * + * Returns BT_STATUS_SUCCESS + * + ******************************************************************************/ +bt_status_t btif_storage_get_hid_connection_policy(const RawAddress& addr, + bool* reconnect_allowed); + /******************************************************************************* * * Function btif_storage_add_hid_device_info diff --git a/btif/src/btif_hh.cc b/btif/src/btif_hh.cc index b6441e1cc..ea6559d34 100644 --- a/btif/src/btif_hh.cc +++ b/btif/src/btif_hh.cc @@ -338,6 +338,24 @@ btif_hh_device_t* btif_hh_find_connected_dev_by_handle(uint8_t handle) { return NULL; } +/******************************************************************************* + * + * Function btif_hh_find_added_dev + * + * Description Return the added device pointer of the specified address + * + * Returns Added device entry + ******************************************************************************/ +btif_hh_added_device_t* btif_hh_find_added_dev(const RawAddress& addr) { + for (int i = 0; i < BTIF_HH_MAX_ADDED_DEV; i++) { + btif_hh_added_device_t* added_dev = &btif_hh_cb.added_devices[i]; + if (added_dev->bd_addr == addr) { + return added_dev; + } + } + return nullptr; +} + /******************************************************************************* * * Function btif_hh_find_dev_by_bda @@ -423,7 +441,8 @@ void btif_hh_start_vup_timer(const RawAddress* bd_addr) { * * Returns true if add successfully, otherwise false. ******************************************************************************/ -bool btif_hh_add_added_dev(const RawAddress& bda, tBTA_HH_ATTR_MASK attr_mask) { +bool btif_hh_add_added_dev(const RawAddress& bda, tBTA_HH_ATTR_MASK attr_mask, + bool reconnect_allowed) { int i; for (i = 0; i < BTIF_HH_MAX_ADDED_DEV; i++) { if (btif_hh_cb.added_devices[i].bd_addr == bda) { @@ -437,6 +456,7 @@ bool btif_hh_add_added_dev(const RawAddress& bda, tBTA_HH_ATTR_MASK attr_mask) { btif_hh_cb.added_devices[i].bd_addr = bda; btif_hh_cb.added_devices[i].dev_handle = BTA_HH_INVALID_HANDLE; btif_hh_cb.added_devices[i].attr_mask = attr_mask; + btif_hh_cb.added_devices[i].reconnect_allowed = reconnect_allowed; return true; } } @@ -692,6 +712,23 @@ void btif_hh_service_registration(bool enable) { * ****************************************************************************/ +static bool btif_hh_connection_allowed(const RawAddress& bda) { + /* Accept connection only if reconnection is allowed for the known device, or + * outgoing connection was requested */ + btif_hh_added_device_t* added_dev = btif_hh_find_added_dev(bda); + if (added_dev != nullptr && added_dev->reconnect_allowed) { + LOG_VERBOSE(LOG_TAG, "Connection allowed %s", bda.ToString().c_str()); + return true; + } else if (btif_hh_cb.pending_conn_address == bda) { + LOG_VERBOSE(LOG_TAG, "Device connection was pending for: %s, status: %s", + bda.ToString().c_str(), + btif_hh_status_text(btif_hh_cb.status).c_str()); + return true; + } + + return false; +} + /******************************************************************************* * * Function btif_hh_upstreams_evt @@ -750,9 +787,26 @@ static void btif_hh_upstreams_evt(uint16_t event, char* p_param) { p_data->status); break; - case BTA_HH_OPEN_EVT: + case BTA_HH_OPEN_EVT: { BTIF_TRACE_WARNING("%s: BTA_HH_OPN_EVT: handle=%d, status =%d", __func__, p_data->conn.handle, p_data->conn.status); + + if (!btif_hh_connection_allowed(p_data->conn.bda)) { + LOG_WARN(LOG_TAG, "Reject Incoming HID Connection, device: %s", + p_data->conn.bda.ToString().c_str()); + btif_hh_device_t* p_dev = + btif_hh_find_connected_dev_by_handle(p_data->conn.handle); + if (p_dev != nullptr) { + p_dev->dev_status = BTHH_CONN_STATE_DISCONNECTED; + } + + btif_hh_cb.status = (BTIF_HH_STATUS)BTIF_HH_DEV_DISCONNECTED; + BTA_HhClose(p_data->conn.handle); + HAL_CBACK(bt_hh_callbacks, connection_state_cb, &p_data->conn.bda, + BTHH_CONN_STATE_DISCONNECTED); + return; + } + btif_hh_cb.pending_conn_address = RawAddress::kEmpty; if (p_data->conn.status == BTA_HH_OK) { p_dev = btif_hh_find_connected_dev_by_handle(p_data->conn.handle); @@ -811,6 +865,7 @@ static void btif_hh_upstreams_evt(uint16_t event, char* p_param) { btif_hh_cb.status = (BTIF_HH_STATUS)BTIF_HH_DEV_DISCONNECTED; } break; + } case BTA_HH_CLOSE_EVT: BTIF_TRACE_DEBUG("BTA_HH_CLOSE_EVT: status = %d, handle = %d", @@ -963,7 +1018,7 @@ static void btif_hh_upstreams_evt(uint16_t event, char* p_param) { p_data->dscp_info.version, p_data->dscp_info.ctry_code, len, p_data->dscp_info.descriptor.dsc_list); - if (btif_hh_add_added_dev(p_dev->bd_addr, p_dev->attr_mask)) { + if (btif_hh_add_added_dev(p_dev->bd_addr, p_dev->attr_mask, true)) { tBTA_HH_DEV_DSCP_INFO dscp_info; bt_status_t ret; btif_hh_copy_hid_info(&dscp_info, &p_data->dscp_info); @@ -979,6 +1034,8 @@ static void btif_hh_upstreams_evt(uint16_t event, char* p_param) { p_data->dscp_info.ssr_min_tout, len, p_data->dscp_info.descriptor.dsc_list); + btif_storage_set_hid_connection_policy(p_dev->bd_addr, true); + ASSERTC(ret == BT_STATUS_SUCCESS, "storing hid info failed", ret); BTIF_TRACE_WARNING("BTA_HH_GET_DSCP_EVT: Called add device"); @@ -1260,6 +1317,13 @@ static bt_status_t init(bthh_callbacks_t* callbacks) { ******************************************************************************/ static bt_status_t connect(RawAddress* bd_addr) { if (btif_hh_cb.status != BTIF_HH_DEV_CONNECTING) { + /* If the device was already added, ensure that reconnections are allowed */ + btif_hh_added_device_t* added_dev = btif_hh_find_added_dev(*bd_addr); + if (added_dev != nullptr && !added_dev->reconnect_allowed) { + added_dev->reconnect_allowed = true; + btif_storage_set_hid_connection_policy(*bd_addr, true); + } + btif_transfer_context(btif_hh_handle_evt, BTIF_HH_CONNECT_REQ_EVT, (char*)bd_addr, sizeof(RawAddress), NULL); return BT_STATUS_SUCCESS; @@ -1276,7 +1340,7 @@ static bt_status_t connect(RawAddress* bd_addr) { * Returns bt_status_t * ******************************************************************************/ -static bt_status_t disconnect(RawAddress* bd_addr) { +static bt_status_t disconnect(RawAddress* bd_addr, bool reconnect_allowed) { CHECK_BTHH_INIT(); BTIF_TRACE_EVENT("BTHH: %s", __func__); btif_hh_device_t* p_dev; @@ -1286,6 +1350,17 @@ static bt_status_t disconnect(RawAddress* bd_addr) { btif_hh_cb.status); return BT_STATUS_FAIL; } + + if (!reconnect_allowed) { + LOG_INFO(LOG_TAG, "Incoming reconnections disabled for device %s", + bd_addr->ToString().c_str()); + btif_hh_added_device_t* added_dev = btif_hh_find_added_dev(*bd_addr); + if (added_dev != nullptr && added_dev->reconnect_allowed) { + added_dev->reconnect_allowed = false; + btif_storage_set_hid_connection_policy(added_dev->bd_addr, false); + } + } + p_dev = btif_hh_find_connected_dev_by_bda(*bd_addr); if (p_dev != NULL) { return btif_transfer_context(btif_hh_handle_evt, BTIF_HH_DISCONNECT_REQ_EVT, @@ -1417,9 +1492,10 @@ static bt_status_t set_info(RawAddress* bd_addr, bthh_hid_info_t hid_info) { (uint8_t*)osi_malloc(dscp_info.descriptor.dl_len); memcpy(dscp_info.descriptor.dsc_list, &(hid_info.dsc_list), hid_info.dl_len); - if (btif_hh_add_added_dev(*bd_addr, hid_info.attr_mask)) { + if (btif_hh_add_added_dev(*bd_addr, hid_info.attr_mask, true)) { BTA_HhAddDev(*bd_addr, hid_info.attr_mask, hid_info.sub_class, hid_info.app_id, dscp_info); + btif_storage_set_hid_connection_policy(*bd_addr, true); } osi_free_and_reset((void**)&dscp_info.descriptor.dsc_list); diff --git a/btif/src/btif_storage.cc b/btif/src/btif_storage.cc index ef2e191eb..f768845dd 100644 --- a/btif/src/btif_storage.cc +++ b/btif/src/btif_storage.cc @@ -85,6 +85,8 @@ using bluetooth::Uuid; #define BTIF_STORAGE_KEY_ADAPTER_SCANMODE "ScanMode" #define BTIF_STORAGE_KEY_ADAPTER_DISC_TIMEOUT "DiscoveryTimeout" +#define BTIF_STORAGE_KEY_HID_RECONNECT_ALLOWED "HidReConnectAllowed" + /* This is a local property to add a device found */ #define BT_PROPERTY_REMOTE_DEVICE_TIMESTAMP 0xFF @@ -1260,6 +1262,50 @@ bt_status_t btif_storage_get_remote_addr_type(const RawAddress* remote_bd_addr, btif_config_get_int(remote_bd_addr->ToString(), "AddrType", addr_type); return ret ? BT_STATUS_SUCCESS : BT_STATUS_FAIL; } + +/******************************************************************************* + * + * Function btif_storage_set_hid_connection_policy + * + * Description Stores connection policy info in nvram + * + * Returns BT_STATUS_SUCCESS + * + ******************************************************************************/ +bt_status_t btif_storage_set_hid_connection_policy(const RawAddress& addr, + bool reconnect_allowed) { + std::string bdstr = addr.ToString(); + + if (btif_config_set_int(bdstr, BTIF_STORAGE_KEY_HID_RECONNECT_ALLOWED, + reconnect_allowed)) { + return BT_STATUS_SUCCESS; + } else { + return BT_STATUS_FAIL; + } +} + +/******************************************************************************* + * + * Function btif_storage_get_hid_connection_policy + * + * Description get connection policy info from nvram + * + * Returns BT_STATUS_SUCCESS + * + ******************************************************************************/ +bt_status_t btif_storage_get_hid_connection_policy(const RawAddress& addr, + bool* reconnect_allowed) { + std::string bdstr = addr.ToString(); + + // For backward compatibility, assume that the reconnection is allowed in the + // absence of the key + int value = 1; + btif_config_get_int(bdstr, BTIF_STORAGE_KEY_HID_RECONNECT_ALLOWED, &value); + *reconnect_allowed = (value != 0); + + return BT_STATUS_SUCCESS; +} + /******************************************************************************* * * Function btif_storage_add_hid_device_info @@ -1362,8 +1408,12 @@ bt_status_t btif_storage_load_bonded_hid_info(void) { RawAddress bd_addr; RawAddress::FromString(name, bd_addr); + + bool reconnect_allowed = false; + btif_storage_get_hid_connection_policy(bd_addr, &reconnect_allowed); + // add extracted information to BTA HH - if (btif_hh_add_added_dev(bd_addr, attr_mask)) { + if (btif_hh_add_added_dev(bd_addr, attr_mask, reconnect_allowed)) { BTA_HhAddDev(bd_addr, attr_mask, sub_class, app_id, dscp_info); } } @@ -1395,6 +1445,7 @@ bt_status_t btif_storage_remove_hid_info(RawAddress* remote_bd_addr) { btif_config_remove(bdstr, "HidSSRMaxLatency"); btif_config_remove(bdstr, "HidSSRMinTimeout"); btif_config_remove(bdstr, "HidDescriptor"); + btif_config_remove(bdstr, BTIF_STORAGE_KEY_HID_RECONNECT_ALLOWED); btif_config_save(); return BT_STATUS_SUCCESS; } diff --git a/include/hardware/bt_hh.h b/include/hardware/bt_hh.h index b87b129bb..923c62792 100644 --- a/include/hardware/bt_hh.h +++ b/include/hardware/bt_hh.h @@ -154,7 +154,7 @@ typedef struct { bt_status_t (*connect)(RawAddress* bd_addr); /** dis-connect from hid device */ - bt_status_t (*disconnect)(RawAddress* bd_addr); + bt_status_t (*disconnect)(RawAddress* bd_addr, bool reconnect_allowed); /** Virtual UnPlug (VUP) the specified HID device */ bt_status_t (*virtual_unplug)(RawAddress* bd_addr);