src/event.c

/*
 *
 *  BlueZ - Bluetooth protocol stack for Linux
 *
 *  Copyright (C) 2006-2010  Nokia Corporation
 *  Copyright (C) 2004-2010  Marcel Holtmann <marcel@holtmann.org>
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#define _GNU_SOURCE
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/socket.h>

#include <bluetooth/bluetooth.h>
#include <bluetooth/hci.h>
#include <bluetooth/hci_lib.h>
#include <bluetooth/sdp.h>

#include <glib.h>
#include <dbus/dbus.h>
#include <gdbus.h>

#include "log.h"
#include "textfile.h"

#include "hcid.h"
#include "manager.h"
#include "adapter.h"
#include "device.h"
#include "error.h"
#include "glib-helper.h"
#include "dbus-common.h"
#include "agent.h"
#include "storage.h"
#include "event.h"

static gboolean get_adapter_and_device(bdaddr_t *src, bdaddr_t *dst,
					struct btd_adapter **adapter,
					struct btd_device **device,
					gboolean create)
{
	DBusConnection *conn = get_dbus_connection();
	char peer_addr[18];

	*adapter = manager_find_adapter(src);
	if (!*adapter) {
		error("Unable to find matching adapter");
		return FALSE;
	}

	ba2str(dst, peer_addr);

	if (create)
		*device = adapter_get_device(conn, *adapter, peer_addr);
	else
		*device = adapter_find_device(*adapter, peer_addr);

	if (create && !*device) {
		error("Unable to get device object!");
		return FALSE;
	}

	return TRUE;
}

/*****************************************************************
 *
 *  Section reserved to HCI commands confirmation handling and low
 *  level events(eg: device attached/dettached.
 *
 *****************************************************************/

static void pincode_cb(struct agent *agent, DBusError *derr,
				const char *pincode, struct btd_device *device)
{
	struct btd_adapter *adapter = device_get_adapter(device);
	bdaddr_t sba, dba;
	int err;

	device_get_address(device, &dba);

	if (derr) {
		err = btd_adapter_pincode_reply(adapter, &dba, NULL);
		if (err < 0)
			goto fail;
		return;
	}

	err = btd_adapter_pincode_reply(adapter, &dba, pincode);
	if (err < 0)
		goto fail;

	adapter_get_address(adapter, &sba);

	return;

fail:
	error("Sending PIN code reply failed: %s (%d)", strerror(-err), -err);
}

int btd_event_request_pin(bdaddr_t *sba, struct hci_conn_info *ci)
{
	struct btd_adapter *adapter;
	struct btd_device *device;

	if (!get_adapter_and_device(sba, &ci->bdaddr, &adapter, &device, TRUE))
		return -ENODEV;

	/* Check if the adapter is not pairable and if there isn't a bonding in
	 * progress */
	if (!adapter_is_pairable(adapter) && !device_is_bonding(device, NULL))
		return -EPERM;

	return device_request_authentication(device, AUTH_TYPE_PINCODE, 0,
								pincode_cb);
}

static int confirm_reply(struct btd_adapter *adapter,
				struct btd_device *device, gboolean success)
{
	bdaddr_t bdaddr;

	device_get_address(device, &bdaddr);

	return btd_adapter_confirm_reply(adapter, &bdaddr, success);
}

static void confirm_cb(struct agent *agent, DBusError *err, void *user_data)
{
	struct btd_device *device = user_data;
	struct btd_adapter *adapter = device_get_adapter(device);
	gboolean success = (err == NULL) ? TRUE : FALSE;

	confirm_reply(adapter, device, success);
}

static void passkey_cb(struct agent *agent, DBusError *err, uint32_t passkey,
			void *user_data)
{
	struct btd_device *device = user_data;
	struct btd_adapter *adapter = device_get_adapter(device);
	bdaddr_t bdaddr;

	device_get_address(device, &bdaddr);

	if (err)
		passkey = INVALID_PASSKEY;

	btd_adapter_passkey_reply(adapter, &bdaddr, passkey);
}

int btd_event_user_confirm(bdaddr_t *sba, bdaddr_t *dba, uint32_t passkey)
{
	struct btd_adapter *adapter;
	struct btd_device *device;
	struct agent *agent;
	uint8_t rem_cap, rem_auth, loc_cap, loc_auth;
	gboolean bonding_initiator;

	if (!get_adapter_and_device(sba, dba, &adapter, &device, TRUE))
		return -ENODEV;

	if (btd_adapter_get_auth_info(adapter, dba, &loc_auth) < 0) {
		error("Unable to get local authentication requirements");
		goto fail;
	}

	agent = device_get_agent(device);
	if (agent == NULL) {
		error("No agent available for user confirmation");
		goto fail;
	}

	loc_cap = agent_get_io_capability(agent);

	DBG("confirm IO capabilities are 0x%02x", loc_cap);
	DBG("confirm authentication requirement is 0x%02x", loc_auth);

	rem_cap = device_get_cap(device);
	rem_auth = device_get_auth(device);

	DBG("remote IO capabilities are 0x%02x", rem_cap);
	DBG("remote authentication requirement is 0x%02x", rem_auth);

	/* If we require MITM but the remote device can't provide that
	 * (it has NoInputNoOutput) then reject the confirmation
	 * request. The only exception is when we're dedicated bonding
	 * initiators since then we always have the MITM bit set. */
	bonding_initiator = device_is_bonding(device, NULL);
	if (!bonding_initiator && (loc_auth & 0x01) && rem_cap == 0x03) {
		error("Rejecting request: remote device can't provide MITM");
		goto fail;
	}

	/* If no side requires MITM protection; auto-accept */
	if ((loc_auth == 0xff || !(loc_auth & 0x01) || rem_cap == 0x03) &&
				(!(rem_auth & 0x01) || loc_cap == 0x03)) {
		DBG("auto accept of confirmation");

		/* Wait 5 milliseconds before doing auto-accept */
		usleep(5000);

		if (confirm_reply(adapter, device, TRUE) < 0)
			return -EIO;

		return device_request_authentication(device, AUTH_TYPE_AUTO,
								0, NULL);
	}

	return device_request_authentication(device, AUTH_TYPE_CONFIRM,
							passkey, confirm_cb);

fail:
	return confirm_reply(adapter, device, FALSE);
}

int btd_event_user_passkey(bdaddr_t *sba, bdaddr_t *dba)
{
	struct btd_adapter *adapter;
	struct btd_device *device;

	if (!get_adapter_and_device(sba, dba, &adapter, &device, TRUE))
		return -ENODEV;

	return device_request_authentication(device, AUTH_TYPE_PASSKEY, 0,
								passkey_cb);
}

int btd_event_user_notify(bdaddr_t *sba, bdaddr_t *dba, uint32_t passkey)
{
	struct btd_adapter *adapter;
	struct btd_device *device;

	if (!get_adapter_and_device(sba, dba, &adapter, &device, TRUE))
		return -ENODEV;

	return device_request_authentication(device, AUTH_TYPE_NOTIFY,
								passkey, NULL);
}

void btd_event_bonding_process_complete(bdaddr_t *local, bdaddr_t *peer,
								uint8_t status)
{
	struct btd_adapter *adapter;
	struct btd_device *device;

	DBG("status=%02x", status);

	if (!get_adapter_and_device(local, peer, &adapter, &device, TRUE))
		return;

	if (!device_is_authenticating(device)) {
		/* This means that there was no pending PIN or SSP token
		 * request from the controller, i.e. this is not a new
		 * pairing */
		DBG("no pending auth request");
		return;
	}

	/* If this is a new pairing send the appropriate reply and signal for
	 * it and proceed with service discovery */
	device_bonding_complete(device, status);
}

void btd_event_simple_pairing_complete(bdaddr_t *local, bdaddr_t *peer,
								uint8_t status)
{
	struct btd_adapter *adapter;
	struct btd_device *device;

	DBG("status=%02x", status);

	if (!get_adapter_and_device(local, peer, &adapter, &device, TRUE))
		return;

	device_simple_pairing_complete(device, status);
}

static char *extract_eir_name(uint8_t *data, uint8_t *type)
{
	if (!data || !type)
		return NULL;

	if (data[0] == 0)
		return NULL;

	*type = data[1];

	switch (*type) {
	case 0x08:
	case 0x09:
		if (!g_utf8_validate((char *) (data + 2), data[0] - 1, NULL))
			return strdup("");
		return strndup((char *) (data + 2), data[0] - 1);
	}

	return NULL;
}

void btd_event_inquiry_result(bdaddr_t *local, bdaddr_t *peer, uint32_t class,
				int8_t rssi, uint8_t *data)
{
	char filename[PATH_MAX + 1];
	struct btd_adapter *adapter;
	struct btd_device *device;
	char local_addr[18], peer_addr[18], *alias, *name, *tmp_name;
	struct remote_dev_info *dev, match;
	uint8_t name_type = 0x00;
	name_status_t name_status;
	int state;
	dbus_bool_t legacy;
	unsigned char features[8];

	ba2str(local, local_addr);
	ba2str(peer, peer_addr);

	if (!get_adapter_and_device(local, peer, &adapter, &device, FALSE)) {
		error("No matching adapter found");
		return;
	}

	write_remote_class(local, peer, class);

	if (data)
		write_remote_eir(local, peer, data);

	/*
	 * Workaround to identify periodic inquiry: inquiry complete event is
	 * sent after each window, however there isn't an event to indicate the
	 * beginning of a new periodic inquiry window.
	 */
	state = adapter_get_state(adapter);
	if (!(state & (STATE_STDINQ | STATE_LE_SCAN | STATE_PINQ))) {
		state |= STATE_PINQ;
		adapter_set_state(adapter, state);
	}

	memset(&match, 0, sizeof(struct remote_dev_info));
	bacpy(&match.bdaddr, peer);
	match.name_status = NAME_SENT;
	/* if found: don't send the name again */
	dev = adapter_search_found_devices(adapter, &match);
	if (dev) {
		adapter_update_found_devices(adapter, peer, rssi, class,
						NULL, NULL, dev->legacy,
						NAME_NOT_REQUIRED, data);
		return;
	}

	/* the inquiry result can be triggered by NON D-Bus client */
	if (adapter_get_discover_type(adapter) & DISC_RESOLVNAME &&
				adapter_has_discov_sessions(adapter))
		name_status = NAME_REQUIRED;
	else
		name_status = NAME_NOT_REQUIRED;

	create_name(filename, PATH_MAX, STORAGEDIR, local_addr, "aliases");
	alias = textfile_get(filename, peer_addr);

	create_name(filename, PATH_MAX, STORAGEDIR, local_addr, "names");
	name = textfile_get(filename, peer_addr);

	if (data)
		legacy = FALSE;
	else if (name == NULL)
		legacy = TRUE;
	else if (read_remote_features(local, peer, NULL, features) == 0) {
		if (features[0] & 0x01)
			legacy = FALSE;
		else
			legacy = TRUE;
	} else
		legacy = TRUE;

	tmp_name = extract_eir_name(data, &name_type);
	if (tmp_name) {
		if (name_type == 0x09) {
			write_device_name(local, peer, tmp_name);
			name_status = NAME_NOT_REQUIRED;

			if (name)
				g_free(name);

			name = tmp_name;
		} else {
			if (name)
				free(tmp_name);
			else
				name = tmp_name;
		}
	}

	if (name && name_type != 0x08)
		name_status = NAME_SENT;

	/* add in the list to track name sent/pending */
	adapter_update_found_devices(adapter, peer, rssi, class, name, alias,
					legacy, name_status, data);

	g_free(name);
	g_free(alias);
}

void btd_event_set_legacy_pairing(bdaddr_t *local, bdaddr_t *peer,
							gboolean legacy)
{
	struct btd_adapter *adapter;
	struct btd_device *device;
	struct remote_dev_info *dev, match;

	if (!get_adapter_and_device(local, peer, &adapter, &device, FALSE)) {
		error("No matching adapter found");
		return;
	}

	memset(&match, 0, sizeof(struct remote_dev_info));
	bacpy(&match.bdaddr, peer);
	match.name_status = NAME_ANY;

	dev = adapter_search_found_devices(adapter, &match);
	if (dev)
		dev->legacy = legacy;
}

void btd_event_remote_class(bdaddr_t *local, bdaddr_t *peer, uint32_t class)
{
	uint32_t old_class = 0;
	struct btd_adapter *adapter;
	struct btd_device *device;
	const gchar *dev_path;
	DBusConnection *conn = get_dbus_connection();

	read_remote_class(local, peer, &old_class);

	if (old_class == class)
		return;

	write_remote_class(local, peer, class);

	if (!get_adapter_and_device(local, peer, &adapter, &device, FALSE))
		return;

	if (!device)
		return;

	dev_path = device_get_path(device);

	emit_property_changed(conn, dev_path, DEVICE_INTERFACE, "Class",
				DBUS_TYPE_UINT32, &class);
}

void btd_event_remote_name(bdaddr_t *local, bdaddr_t *peer, uint8_t status,
				char *name)
{
	struct btd_adapter *adapter;
	char srcaddr[18], dstaddr[18];
	int state;
	struct btd_device *device;
	struct remote_dev_info match, *dev_info;

	if (status == 0) {
		char *end;

		/* It's ok to cast end between const and non-const since
		 * we know it points to inside of name which is non-const */
		if (!g_utf8_validate(name, -1, (const char **) &end))
			*end = '\0';

		write_device_name(local, peer, name);
	}

	if (!get_adapter_and_device(local, peer, &adapter, &device, FALSE))
		return;

	ba2str(local, srcaddr);
	ba2str(peer, dstaddr);

	if (status != 0)
		goto proceed;

	bacpy(&match.bdaddr, peer);
	match.name_status = NAME_ANY;

	dev_info = adapter_search_found_devices(adapter, &match);
	if (dev_info) {
		g_free(dev_info->name);
		dev_info->name = g_strdup(name);
		adapter_emit_device_found(adapter, dev_info, NULL, 0);
	}

	if (device)
		device_set_name(device, name);

proceed:
	/* remove from remote name request list */
	adapter_remove_found_device(adapter, peer);

	/* check if there is more devices to request names */
	if (adapter_resolve_names(adapter) == 0)
		return;

	state = adapter_get_state(adapter);
	state &= ~STATE_RESOLVNAME;
	adapter_set_state(adapter, state);
}

int btd_event_link_key_notify(bdaddr_t *local, bdaddr_t *peer,
				uint8_t *key, uint8_t key_type,
				int pin_length, uint8_t old_key_type)
{
	struct btd_device *device;
	struct btd_adapter *adapter;
	uint8_t local_auth = 0xff, remote_auth, new_key_type;
	gboolean bonding, temporary = FALSE;

	if (!get_adapter_and_device(local, peer, &adapter, &device, TRUE))
		return -ENODEV;

	remote_auth = device_get_auth(device);

	new_key_type = key_type;

	if (key_type == 0x06) {
		if (device_get_debug_key(device, NULL))
			old_key_type = 0x03;
		/* Some buggy controller combinations generate a changed
		 * combination key for legacy pairing even when there's no
		 * previous key */
		if (remote_auth == 0xff && old_key_type == 0xff)
			new_key_type = key_type = 0x00;
		else if (old_key_type != 0xff)
			new_key_type = old_key_type;
		else
			/* This is Changed Combination Link Key for
			 * a temporary link key.*/
			return 0;
	}

	btd_adapter_get_auth_info(adapter, peer, &local_auth);
	bonding = device_is_bonding(device, NULL);

	DBG("key type 0x%02x old key type 0x%02x new key type 0x%02x",
					key_type, old_key_type, new_key_type);

	DBG("local auth 0x%02x and remote auth 0x%02x",
					local_auth, remote_auth);

	/* Clear any previous debug key */
	device_set_debug_key(device, NULL);

	/* If this is not the first link key set a flag so a subsequent auth
	 * complete event doesn't trigger SDP and remove any stored key */
	if (old_key_type != 0xff) {
		device_set_renewed_key(device, TRUE);
		device_remove_bonding(device);
	}

	/* Store the link key only in runtime memory if it's a debug
	 * key, else store the link key persistently if one of the
	 * following is true:
	 * 1. this is a legacy link key
	 * 2. this is a changed combination key and there was a previously
	 *    stored one
	 * 3. neither local nor remote side had no-bonding as a requirement
	 * 4. the local side had dedicated bonding as a requirement
	 * 5. the remote side is using dedicated bonding since in that case
	 *    also the local requirements are set to dedicated bonding
	 * If none of the above match only keep the link key around for
	 * this connection and set the temporary flag for the device.
	 */
	if (new_key_type == 0x03) {
		DBG("Storing debug key in runtime memory");
		device_set_debug_key(device, key);
	} else if (key_type < 0x03 ||
				(key_type == 0x06 && old_key_type != 0xff) ||
				(local_auth > 0x01 && remote_auth > 0x01) ||
				(local_auth == 0x02 || local_auth == 0x03) ||
				(remote_auth == 0x02 || remote_auth == 0x03)) {
		int err;

		DBG("storing link key of type 0x%02x", key_type);

		err = write_link_key(local, peer, key, new_key_type,
								pin_length);
		if (err < 0) {
			error("write_link_key: %s (%d)", strerror(-err), -err);
			return err;
		}
	} else
		temporary = TRUE;

	if (!device_is_connected(device))
		device_set_secmode3_conn(device, TRUE);
	else if (!bonding && old_key_type == 0xff)
		btd_event_bonding_process_complete(local, peer, 0);

	device_set_temporary(device, temporary);

	return 0;
}

void btd_event_conn_complete(bdaddr_t *local, uint8_t status, uint16_t handle,
				bdaddr_t *peer)
{
	struct btd_adapter *adapter;
	struct btd_device *device;
	DBusConnection *conn = get_dbus_connection();

	if (!get_adapter_and_device(local, peer, &adapter, &device, TRUE))
		return;

	if (status) {
		gboolean secmode3 = device_get_secmode3_conn(device);

		device_set_secmode3_conn(device, FALSE);

		if (device_is_bonding(device, NULL))
			device_bonding_complete(device, status);
		if (device_is_temporary(device))
			adapter_remove_device(conn, adapter, device, secmode3);
		return;
	}

	/* add in the device connetions list */
	adapter_add_connection(adapter, device, handle);
}

void btd_event_disconn_complete(bdaddr_t *local, uint8_t status,
				uint16_t handle, uint8_t reason)
{
	struct btd_adapter *adapter;
	struct btd_device *device;

	if (status) {
		error("Disconnection failed: 0x%02x", status);
		return;
	}

	adapter = manager_find_adapter(local);
	if (!adapter) {
		error("No matching adapter found");
		return;
	}

	device = adapter_find_connection(adapter, handle);
	if (!device) {
		DBG("No matching connection found for handle %u", handle);
		return;
	}

	adapter_remove_connection(adapter, device, handle);
}

/* Section reserved to device HCI callbacks */

void btd_event_setscan_enable_complete(bdaddr_t *local)
{
	struct btd_adapter *adapter;

	adapter = manager_find_adapter(local);
	if (!adapter) {
		error("No matching adapter found");
		return;
	}

	if (adapter_powering_down(adapter))
		return;

	btd_adapter_read_scan_enable(adapter);
}

void btd_event_le_set_scan_enable_complete(bdaddr_t *local, uint8_t status)
{
	struct btd_adapter *adapter;
	int state;

	adapter = manager_find_adapter(local);
	if (!adapter) {
		error("No matching adapter found");
		return;
	}

	if (status) {
		error("Can't enabled/disable LE scan");
		return;
	}

	state = adapter_get_state(adapter);

	/* Enabling or disabling ? */
	if (state & STATE_LE_SCAN)
		state &= ~STATE_LE_SCAN;
	else
		state |= STATE_LE_SCAN;

	adapter_set_state(adapter, state);
}

void btd_event_read_simple_pairing_mode_complete(bdaddr_t *local, void *ptr)
{
	read_simple_pairing_mode_rp *rp = ptr;
	struct btd_adapter *adapter;

	if (rp->status)
		return;

	adapter = manager_find_adapter(local);
	if (!adapter) {
		error("No matching adapter found");
		return;
	}

	adapter_update_ssp_mode(adapter, rp->mode);
}

void btd_event_returned_link_key(bdaddr_t *local, bdaddr_t *peer)
{
	struct btd_adapter *adapter;
	struct btd_device *device;

	if (!get_adapter_and_device(local, peer, &adapter, &device, TRUE))
		return;

	device_set_paired(device, TRUE);
}

int btd_event_get_io_cap(bdaddr_t *local, bdaddr_t *remote,
						uint8_t *cap, uint8_t *auth)
{
	struct btd_adapter *adapter;
	struct btd_device *device;
	struct agent *agent = NULL;
	uint8_t agent_cap;
	int err;

	if (!get_adapter_and_device(local, remote, &adapter, &device, TRUE))
		return -ENODEV;

	err = btd_adapter_get_auth_info(adapter, remote, auth);
	if (err < 0)
		return err;

	DBG("initial authentication requirement is 0x%02x", *auth);

	if (*auth == 0xff)
		*auth = device_get_auth(device);

	/* Check if the adapter is not pairable and if there isn't a bonding
	 * in progress */
	if (!adapter_is_pairable(adapter) &&
				!device_is_bonding(device, NULL)) {
		if (device_get_auth(device) < 0x02) {
			DBG("Allowing no bonding in non-bondable mode");
			/* No input, no output */
			*cap = 0x03;
			/* Kernel defaults to general bonding and so
			 * overwrite for this special case. Otherwise
			 * non-pairable test cases will fail. */
			*auth = 0x00;
			goto done;
		}
		return -EPERM;
	}

	/* For CreatePairedDevice use dedicated bonding */
	agent = device_get_agent(device);
	if (!agent) {
		/* This is the non bondable mode case */
		if (device_get_auth(device) > 0x01) {
			DBG("Bonding request, but no agent present");
			return -1;
		}

		/* No agent available, and no bonding case */
		if (*auth == 0x00 || *auth == 0x04) {
			DBG("Allowing no bonding without agent");
			/* No input, no output */
			*cap = 0x03;
			/* If kernel defaults to general bonding, set it
			 * back to no bonding */
			*auth = 0x00;
			goto done;
		}

		error("No agent available for IO capability");
		return -1;
	}

	agent_cap = agent_get_io_capability(agent);

	if (*auth == 0x00 || *auth == 0x04) {
		/* If remote requests dedicated bonding follow that lead */
		if (device_get_auth(device) == 0x02 ||
				device_get_auth(device) == 0x03) {

			/* If both remote and local IO capabilities allow MITM
			 * then require it, otherwise don't */
			if (device_get_cap(device) == 0x03 ||
							agent_cap == 0x03)
				*auth = 0x02;
			else
				*auth = 0x03;
		}

		/* If remote indicates no bonding then follow that. This
		 * is important since the kernel might give general bonding
		 * as default. */
		if (device_get_auth(device) == 0x00 ||
					device_get_auth(device) == 0x01)
			*auth = 0x00;

		/* If remote requires MITM then also require it, unless
		 * our IO capability is NoInputNoOutput (so some
		 * just-works security cases can be tested) */
		if (device_get_auth(device) != 0xff &&
					(device_get_auth(device) & 0x01) &&
					agent_cap != 0x03)
			*auth |= 0x01;
	}

	*cap = agent_get_io_capability(agent);

done:
	DBG("final authentication requirement is 0x%02x", *auth);

	return 0;
}

int btd_event_set_io_cap(bdaddr_t *local, bdaddr_t *remote,
						uint8_t cap, uint8_t auth)
{
	struct btd_adapter *adapter;
	struct btd_device *device;

	if (!get_adapter_and_device(local, remote, &adapter, &device, TRUE))
		return -ENODEV;

	device_set_cap(device, cap);
	device_set_auth(device, auth);

	return 0;
}