This change adds a configuration for platforms to choose a more secure posture for the HID profile. While some older mice are known to not support pairing or encryption, some platform may choose a more secure posture by requiring the device to be bonded and require the connection to be encrypted when bonding is required. Reference: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00352.html --- profiles/input/device.c | 23 ++++++++++++++++++++++- profiles/input/device.h | 1 + profiles/input/input.conf | 8 ++++++++ profiles/input/manager.c | 13 ++++++++++++- 4 files changed, 43 insertions(+), 2 deletions(-) diff --git a/profiles/input/device.c b/profiles/input/device.c index 2cb3811c8..7fb22b18f 100644 --- a/profiles/input/device.c +++ b/profiles/input/device.c @@ -92,6 +92,7 @@ struct input_device { static int idle_timeout = 0; static bool uhid_enabled = false; +static bool br_bonded_only = false; void input_set_idle_timeout(int timeout) { @@ -103,6 +104,11 @@ void input_enable_userspace_hid(bool state) uhid_enabled = state; } +void input_set_br_bonded_only(bool state) +{ + br_bonded_only = state; +} + static void input_device_enter_reconnect_mode(struct input_device *idev); static int connection_disconnect(struct input_device *idev, uint32_t flags); @@ -970,8 +976,18 @@ static int hidp_add_connection(struct input_device *idev) if (device_name_known(idev->device)) device_get_name(idev->device, req->name, sizeof(req->name)); + /* Make sure the device is bonded if required */ + if (br_bonded_only && !device_is_bonded(idev->device, + btd_device_get_bdaddr_type(idev->device))) { + error("Rejected connection from !bonded device %s", dst_addr); + goto cleanup; + } + /* Encryption is mandatory for keyboards */ - if (req->subclass & 0x40) { + /* Some platforms may choose to require encryption for all devices */ + /* Note that this only matters for pre 2.1 devices as otherwise the */ + /* device is encrypted by default by the lower layers */ + if (br_bonded_only || req->subclass & 0x40) { if (!bt_io_set(idev->intr_io, &gerr, BT_IO_OPT_SEC_LEVEL, BT_IO_SEC_MEDIUM, BT_IO_OPT_INVALID)) { @@ -1203,6 +1219,11 @@ static void input_device_enter_reconnect_mode(struct input_device *idev) DBG("path=%s reconnect_mode=%s", idev->path, reconnect_mode_to_string(idev->reconnect_mode)); + /* Make sure the device is bonded if required */ + if (br_bonded_only && !device_is_bonded(idev->device, + btd_device_get_bdaddr_type(idev->device))) + return; + /* Only attempt an auto-reconnect when the device is required to * accept reconnections from the host. */ diff --git a/profiles/input/device.h b/profiles/input/device.h index 51a9aee18..aaf312f0e 100644 --- a/profiles/input/device.h +++ b/profiles/input/device.h @@ -29,6 +29,7 @@ struct input_conn; void input_set_idle_timeout(int timeout); void input_enable_userspace_hid(bool state); +void input_set_br_bonded_only(bool state); int input_device_register(struct btd_service *service); void input_device_unregister(struct btd_service *service); diff --git a/profiles/input/input.conf b/profiles/input/input.conf index 3e1d65aae..58791b7e6 100644 --- a/profiles/input/input.conf +++ b/profiles/input/input.conf @@ -11,3 +11,11 @@ # Enable HID protocol handling in userspace input profile # Defaults to false (HIDP handled in HIDP kernel module) #UserspaceHID=true + +# Limit HID connections to bonded devices +# The HID Profile does not specify that devices must be bonded, however some +# platforms may want to make sure that input connections only come from bonded +# device connections. Several older mice have been known for not supporting +# pairing/encryption. +# Defaults to false to maximize device compatibility. +#BrBondedOnly=true diff --git a/profiles/input/manager.c b/profiles/input/manager.c index 1d31b0652..ec45e1649 100644 --- a/profiles/input/manager.c +++ b/profiles/input/manager.c @@ -96,7 +96,7 @@ static int input_init(void) config = load_config_file(CONFIGDIR "/input.conf"); if (config) { int idle_timeout; - gboolean uhid_enabled; + gboolean uhid_enabled, br_bonded_only; idle_timeout = g_key_file_get_integer(config, "General", "IdleTimeout", &err); @@ -114,6 +114,17 @@ static int input_init(void) input_enable_userspace_hid(uhid_enabled); } else g_clear_error(&err); + + br_bonded_only = g_key_file_get_boolean(config, "General", + "BrBondedOnly", &err); + + if (!err) { + DBG("input.conf: BrBondedOnly=%s", br_bonded_only ? + "true" : "false"); + input_set_br_bonded_only(br_bonded_only); + } else + g_clear_error(&err); + } btd_profile_register(&input_profile); -- 2.25.1.481.gfbce0eb801-goog
