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mirror of https://git.kernel.org/pub/scm/network/wireless/iwd.git synced 2024-11-09 05:29:23 +01:00
iwd/src/adhoc.c
James Prestwood 8606bd6435 adhoc: set operstate on Start/Stop
Similar to 06aa84cca set the operstate when AdHoc is started and
stopped as it is no longer always set by netdev (only for station/p2p
interface types)
2021-04-30 20:07:19 -05:00

786 lines
19 KiB
C

/*
*
* Wireless daemon for Linux
*
* Copyright (C) 2018-2019 Intel Corporation. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; 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
#include <linux/rtnetlink.h>
#include <linux/if.h>
#include <ell/ell.h>
#include "linux/nl80211.h"
#include "src/iwd.h"
#include "src/module.h"
#include "src/netdev.h"
#include "src/wiphy.h"
#include "src/crypto.h"
#include "src/ie.h"
#include "src/util.h"
#include "src/eapol.h"
#include "src/handshake.h"
#include "src/mpdu.h"
#include "src/dbus.h"
#include "src/nl80211util.h"
struct adhoc_state {
struct netdev *netdev;
struct l_genl_family *nl80211;
char *ssid;
uint8_t pmk[32];
struct l_queue *sta_states;
uint32_t sta_watch_id;
uint32_t netdev_watch_id;
unsigned int mlme_watch;
struct l_dbus_message *pending;
uint32_t ciphers;
uint32_t group_cipher;
uint8_t gtk[CRYPTO_MAX_GTK_LEN];
uint8_t gtk_index;
bool started : 1;
bool open : 1;
bool gtk_set : 1;
};
struct sta_state {
uint8_t addr[6];
struct adhoc_state *adhoc;
struct eapol_sm *sm;
struct handshake_state *hs_sta;
struct eapol_sm *sm_a;
struct handshake_state *hs_auth;
uint32_t gtk_query_cmd_id;
bool hs_sta_done : 1;
bool hs_auth_done : 1;
bool authenticated : 1;
};
static uint32_t netdev_watch;
static void adhoc_sta_free(void *data)
{
struct sta_state *sta = data;
if (sta->adhoc->open)
goto end;
if (sta->gtk_query_cmd_id)
l_genl_family_cancel(sta->adhoc->nl80211,
sta->gtk_query_cmd_id);
if (sta->sm)
eapol_sm_free(sta->sm);
if (sta->hs_sta)
handshake_state_free(sta->hs_sta);
if (sta->sm_a)
eapol_sm_free(sta->sm_a);
if (sta->hs_auth)
handshake_state_free(sta->hs_auth);
end:
l_free(sta);
}
static void adhoc_remove_sta(struct sta_state *sta)
{
if (!l_queue_remove(sta->adhoc->sta_states, sta)) {
l_error("station %p was not found", sta);
return;
}
if (sta->gtk_query_cmd_id) {
l_genl_family_cancel(sta->adhoc->nl80211,
sta->gtk_query_cmd_id);
sta->gtk_query_cmd_id = 0;
}
/* signal station has been removed */
if (sta->authenticated) {
l_dbus_property_changed(dbus_get_bus(),
netdev_get_path(sta->adhoc->netdev),
IWD_ADHOC_INTERFACE, "ConnectedPeers");
}
adhoc_sta_free(sta);
}
static void adhoc_reset(struct adhoc_state *adhoc)
{
if (adhoc->pending)
dbus_pending_reply(&adhoc->pending,
dbus_error_aborted(adhoc->pending));
l_free(adhoc->ssid);
adhoc->ssid = NULL;
netdev_station_watch_remove(adhoc->netdev, adhoc->sta_watch_id);
adhoc->sta_watch_id = 0;
l_queue_destroy(adhoc->sta_states, adhoc_sta_free);
adhoc->sta_states = NULL;
adhoc->started = false;
l_dbus_property_changed(dbus_get_bus(), netdev_get_path(adhoc->netdev),
IWD_ADHOC_INTERFACE, "Started");
if (adhoc->mlme_watch)
l_genl_family_unregister(adhoc->nl80211, adhoc->mlme_watch);
}
static void adhoc_set_rsn_info(struct adhoc_state *adhoc,
struct ie_rsn_info *rsn)
{
memset(rsn, 0, sizeof(*rsn));
rsn->akm_suites = IE_RSN_AKM_SUITE_PSK;
rsn->pairwise_ciphers = adhoc->ciphers;
rsn->group_cipher = adhoc->group_cipher;
}
static bool ap_sta_match_addr(const void *a, const void *b)
{
const struct sta_state *sta = a;
return !memcmp(sta->addr, b, 6);
}
static void adhoc_operstate_cb(int error, uint16_t type,
const void *data,
uint32_t len, void *user_data)
{
if (!error)
return;
l_debug("netdev: %u, error: %s", L_PTR_TO_UINT(user_data),
strerror(-error));
}
static void adhoc_handshake_event(struct handshake_state *hs,
enum handshake_event event, void *user_data, ...)
{
struct sta_state *sta = user_data;
struct adhoc_state *adhoc = sta->adhoc;
va_list args;
switch (event) {
case HANDSHAKE_EVENT_FAILED:
va_start(args, user_data);
l_error("handshake failed with STA "MAC" (%d)",
MAC_STR(sta->addr),
va_arg(args, int));
va_end(args);
/*
* eapol frees the state machines upon handshake failure. Since
* this is only a failure on one of the handshakes we need to
* set the failing SM to NULL so it will not get double freed
* by adhoc_remove_sta.
*/
if (sta->hs_auth == hs)
sta->sm_a = NULL;
else
sta->sm = NULL;
/* fall through */
case HANDSHAKE_EVENT_SETTING_KEYS_FAILED:
adhoc_remove_sta(sta);
return;
case HANDSHAKE_EVENT_COMPLETE:
if (sta->hs_auth == hs)
sta->hs_auth_done = true;
if (sta->hs_sta == hs)
sta->hs_sta_done = true;
if ((sta->hs_auth_done && sta->hs_sta_done) &&
!sta->authenticated) {
sta->authenticated = true;
l_dbus_property_changed(dbus_get_bus(),
netdev_get_path(adhoc->netdev),
IWD_ADHOC_INTERFACE, "ConnectedPeers");
}
break;
default:
break;
}
}
static struct eapol_sm *adhoc_new_sm(struct sta_state *sta, bool authenticator,
const uint8_t *gtk_rsc)
{
struct adhoc_state *adhoc = sta->adhoc;
struct netdev *netdev = adhoc->netdev;
const uint8_t *own_addr = netdev_get_address(netdev);
struct ie_rsn_info rsn;
uint8_t bss_rsne[24];
struct handshake_state *hs;
struct eapol_sm *sm;
/* fill in only what handshake setup requires */
adhoc_set_rsn_info(adhoc, &rsn);
ie_build_rsne(&rsn, bss_rsne);
hs = netdev_handshake_state_new(netdev);
if (!hs) {
l_error("could not create handshake object");
return NULL;
}
handshake_state_set_event_func(hs, adhoc_handshake_event, sta);
handshake_state_set_ssid(hs, (void *)adhoc->ssid, strlen(adhoc->ssid));
/* we don't have the connecting peer rsn info, so just set ap == own */
handshake_state_set_authenticator_ie(hs, bss_rsne);
handshake_state_set_supplicant_ie(hs, bss_rsne);
handshake_state_set_pmk(hs, adhoc->pmk, 32);
if (authenticator) {
handshake_state_set_authenticator_address(hs, own_addr);
handshake_state_set_supplicant_address(hs, sta->addr);
handshake_state_set_authenticator(hs, true);
} else {
handshake_state_set_authenticator_address(hs, sta->addr);
handshake_state_set_supplicant_address(hs, own_addr);
}
if (gtk_rsc)
handshake_state_set_gtk(hs, adhoc->gtk, adhoc->gtk_index,
gtk_rsc);
sm = eapol_sm_new(hs);
if (!sm) {
l_error("could not create sm object");
return NULL;
}
eapol_sm_set_listen_interval(sm, 100);
if (authenticator)
sta->hs_auth = hs;
else
sta->hs_sta = hs;
return sm;
}
static void adhoc_free(struct adhoc_state *adhoc)
{
adhoc_reset(adhoc);
l_genl_family_free(adhoc->nl80211);
l_free(adhoc);
}
static void adhoc_start_rsna(struct sta_state *sta, const uint8_t *gtk_rsc)
{
sta->sm_a = adhoc_new_sm(sta, true, gtk_rsc);
if (!sta->sm_a) {
l_error("could not create authenticator state machine");
goto failed;
}
sta->sm = adhoc_new_sm(sta, false, NULL);
if (!sta->sm) {
l_error("could not create station state machine");
goto failed;
}
eapol_register(sta->sm);
eapol_register(sta->sm_a);
eapol_start(sta->sm);
eapol_start(sta->sm_a);
return;
failed:
adhoc_remove_sta(sta);
}
static void adhoc_gtk_op_cb(struct l_genl_msg *msg, void *user_data)
{
if (l_genl_msg_get_error(msg) < 0) {
uint8_t cmd = l_genl_msg_get_command(msg);
const char *cmd_name =
cmd == NL80211_CMD_NEW_KEY ? "NEW_KEY" : "SET_KEY";
l_error("%s failed for the GTK: %i",
cmd_name, l_genl_msg_get_error(msg));
}
}
static void adhoc_gtk_query_cb(struct l_genl_msg *msg, void *user_data)
{
struct sta_state *sta = user_data;
const void *gtk_rsc;
sta->gtk_query_cmd_id = 0;
gtk_rsc = nl80211_parse_get_key_seq(msg);
if (!gtk_rsc)
goto error;
adhoc_start_rsna(sta, gtk_rsc);
return;
error:
adhoc_remove_sta(sta);
}
static void adhoc_new_station(struct adhoc_state *adhoc, const uint8_t *mac)
{
struct sta_state *sta;
struct l_genl_msg *msg;
sta = l_queue_find(adhoc->sta_states, ap_sta_match_addr, mac);
if (sta) {
l_warn("new station event with already connected STA");
return;
}
/*
* Follows same logic as AP. If this is the first station we create and
* set a group key. Any subsequent connections will use GET_KEY for this
* tx GTK.
*/
if (adhoc->group_cipher != IE_RSN_CIPHER_SUITE_NO_GROUP_TRAFFIC &&
!adhoc->gtk_set && !adhoc->open) {
enum crypto_cipher group_cipher =
ie_rsn_cipher_suite_to_cipher(adhoc->group_cipher);
int gtk_len = crypto_cipher_key_len(group_cipher);
/*
* Generate our GTK. Not following the example derivation
* method in 802.11-2016 section 12.7.1.4 because a simple
* l_getrandom is just as good.
*/
l_getrandom(adhoc->gtk, gtk_len);
adhoc->gtk_index = 1;
msg = nl80211_build_new_key_group(
netdev_get_ifindex(adhoc->netdev),
group_cipher, adhoc->gtk_index,
adhoc->gtk, gtk_len, NULL,
0, NULL);
if (!l_genl_family_send(adhoc->nl80211, msg, adhoc_gtk_op_cb,
NULL, NULL)) {
l_genl_msg_unref(msg);
l_error("Issuing NEW_KEY failed");
return;
}
msg = nl80211_build_set_key(netdev_get_ifindex(adhoc->netdev),
adhoc->gtk_index);
if (!l_genl_family_send(adhoc->nl80211, msg, adhoc_gtk_op_cb,
NULL, NULL)) {
l_genl_msg_unref(msg);
l_error("Issuing SET_KEY failed");
return;
}
/*
* Set the flag now because any new associating STA will
* just use NL80211_CMD_GET_KEY from now.
*/
adhoc->gtk_set = true;
}
sta = l_new(struct sta_state, 1);
memset(sta, 0, sizeof(struct sta_state));
memcpy(sta->addr, mac, 6);
sta->adhoc = adhoc;
l_queue_push_tail(adhoc->sta_states, sta);
l_info("new Station: "MAC" adhoc=%p", MAC_STR(mac), adhoc);
/* with open networks nothing else is required */
if (sta->adhoc->open) {
int ifindex = netdev_get_ifindex(adhoc->netdev);
sta->authenticated = true;
l_rtnl_set_linkmode_and_operstate(iwd_get_rtnl(), ifindex,
IF_LINK_MODE_DORMANT, IF_OPER_UP,
adhoc_operstate_cb,
L_UINT_TO_PTR(ifindex), NULL);
l_dbus_property_changed(dbus_get_bus(),
netdev_get_path(adhoc->netdev),
IWD_ADHOC_INTERFACE, "ConnectedPeers");
return;
}
if (adhoc->group_cipher == IE_RSN_CIPHER_SUITE_NO_GROUP_TRAFFIC)
adhoc_start_rsna(sta, NULL);
else {
msg = nl80211_build_get_key(netdev_get_ifindex(adhoc->netdev),
adhoc->gtk_index);
sta->gtk_query_cmd_id = l_genl_family_send(adhoc->nl80211, msg,
adhoc_gtk_query_cb,
sta, NULL);
if (!sta->gtk_query_cmd_id) {
l_genl_msg_unref(msg);
l_error("Issuing GET_KEY failed");
adhoc_remove_sta(sta);
return;
}
}
}
static void adhoc_del_station(struct adhoc_state *adhoc, const uint8_t *mac)
{
struct sta_state *sta;
sta = l_queue_find(adhoc->sta_states, ap_sta_match_addr, mac);
if (!sta) {
l_warn("could not find station "MAC" in list", MAC_STR(mac));
return;
}
l_debug("lost station "MAC, MAC_STR(mac));
adhoc_remove_sta(sta);
}
static void adhoc_station_changed_cb(struct netdev *netdev,
const uint8_t *mac, bool added, void *user_data)
{
struct adhoc_state *adhoc = user_data;
if (added)
adhoc_new_station(adhoc, mac);
else
adhoc_del_station(adhoc, mac);
}
static void adhoc_join_cb(struct netdev *netdev, int result, void *user_data)
{
struct adhoc_state *adhoc = user_data;
struct l_dbus_message *reply;
if (result < 0) {
l_error("Failed to join adhoc network, %i", result);
dbus_pending_reply(&adhoc->pending,
dbus_error_failed(adhoc->pending));
return;
}
l_rtnl_set_linkmode_and_operstate(iwd_get_rtnl(),
netdev_get_ifindex(adhoc->netdev),
IF_LINK_MODE_DEFAULT, IF_OPER_UP,
NULL, NULL, NULL);
adhoc->sta_watch_id = netdev_station_watch_add(netdev,
adhoc_station_changed_cb, adhoc);
reply = l_dbus_message_new_method_return(adhoc->pending);
dbus_pending_reply(&adhoc->pending, reply);
}
static void adhoc_mlme_notify(struct l_genl_msg *msg, void *user_data)
{
struct adhoc_state *adhoc = user_data;
uint32_t ifindex;
if (nl80211_parse_attrs(msg, NL80211_ATTR_IFINDEX, &ifindex,
NL80211_ATTR_UNSPEC) < 0 ||
ifindex != netdev_get_ifindex(adhoc->netdev))
return;
switch (l_genl_msg_get_command(msg)) {
case NL80211_CMD_JOIN_IBSS:
/*
* if watch is set the join_ibss_cb has come back. This event
* will come in for each new STA joining the IBSS so we only
* want to set it once
*/
if (adhoc->sta_watch_id && !adhoc->started) {
adhoc->started = true;
l_dbus_property_changed(dbus_get_bus(),
netdev_get_path(adhoc->netdev),
IWD_ADHOC_INTERFACE, "Started");
}
break;
}
}
static struct l_dbus_message *adhoc_dbus_start(struct l_dbus *dbus,
struct l_dbus_message *message,
void *user_data)
{
struct adhoc_state *adhoc = user_data;
struct netdev *netdev = adhoc->netdev;
struct wiphy *wiphy = netdev_get_wiphy(netdev);
const char *ssid, *wpa2_psk;
struct ie_rsn_info rsn;
struct iovec rsn_ie;
uint8_t ie_elems[32];
if (adhoc->pending)
return dbus_error_busy(message);
if (!l_dbus_message_get_arguments(message, "ss", &ssid, &wpa2_psk))
return dbus_error_invalid_args(message);
adhoc->ssid = l_strdup(ssid);
adhoc->pending = l_dbus_message_ref(message);
adhoc->sta_states = l_queue_new();
adhoc->ciphers = wiphy_select_cipher(wiphy, 0xffff);
adhoc->group_cipher = wiphy_select_cipher(wiphy, 0xffff);
adhoc_set_rsn_info(adhoc, &rsn);
ie_build_rsne(&rsn, ie_elems);
rsn_ie.iov_base = ie_elems;
rsn_ie.iov_len = ie_elems[1] + 2;
if (crypto_psk_from_passphrase(wpa2_psk, (uint8_t *) ssid,
strlen(ssid), adhoc->pmk))
return dbus_error_invalid_args(message);
if (netdev_join_adhoc(netdev, ssid, &rsn_ie, 1, true, adhoc_join_cb,
adhoc))
return dbus_error_invalid_args(message);
adhoc->mlme_watch = l_genl_family_register(adhoc->nl80211, "mlme",
adhoc_mlme_notify, adhoc, NULL);
if (!adhoc->mlme_watch)
return dbus_error_failed(message);
return NULL;
}
static struct l_dbus_message *adhoc_dbus_start_open(struct l_dbus *dbus,
struct l_dbus_message *message, void *user_data)
{
struct adhoc_state *adhoc = user_data;
struct netdev *netdev = adhoc->netdev;
const char *ssid;
struct iovec rsn_ie;
uint8_t ie_elems[10];
if (adhoc->pending)
return dbus_error_busy(message);
if (!l_dbus_message_get_arguments(message, "s", &ssid))
return dbus_error_invalid_args(message);
adhoc->ssid = l_strdup(ssid);
adhoc->pending = l_dbus_message_ref(message);
adhoc->sta_states = l_queue_new();
adhoc->open = true;
/* Mac/iPhone seem to require the extended capabilities field */
memset(ie_elems, 0, sizeof(ie_elems));
ie_elems[0] = IE_TYPE_EXTENDED_CAPABILITIES;
ie_elems[1] = 8;
rsn_ie.iov_base = ie_elems;
rsn_ie.iov_len = ie_elems[1] + 2;
if (netdev_join_adhoc(netdev, ssid, &rsn_ie, 1, false, adhoc_join_cb,
adhoc))
return dbus_error_invalid_args(message);
adhoc->mlme_watch = l_genl_family_register(adhoc->nl80211, "mlme",
adhoc_mlme_notify, adhoc, NULL);
if (!adhoc->mlme_watch)
return dbus_error_failed(message);
return NULL;
}
static void adhoc_leave_cb(struct netdev *netdev, int result, void *user_data)
{
struct adhoc_state *adhoc = user_data;
if (result < 0) {
l_error("Failed to leave adhoc network, %i", result);
dbus_pending_reply(&adhoc->pending,
dbus_error_failed(adhoc->pending));
return;
}
dbus_pending_reply(&adhoc->pending,
l_dbus_message_new_method_return(adhoc->pending));
adhoc_reset(adhoc);
}
static struct l_dbus_message *adhoc_dbus_stop(struct l_dbus *dbus,
struct l_dbus_message *message,
void *user_data)
{
struct adhoc_state *adhoc = user_data;
if (adhoc->pending)
return dbus_error_busy(message);
/* already stopped, no-op */
if (!adhoc->started)
return l_dbus_message_new_method_return(message);
if (netdev_leave_adhoc(adhoc->netdev, adhoc_leave_cb, adhoc))
return dbus_error_failed(message);
l_rtnl_set_linkmode_and_operstate(iwd_get_rtnl(),
netdev_get_ifindex(adhoc->netdev),
IF_LINK_MODE_DORMANT, IF_OPER_DOWN,
NULL, NULL, NULL);
adhoc->pending = l_dbus_message_ref(message);
return NULL;
}
static void sta_append(void *data, void *user_data)
{
struct sta_state *sta = data;
struct l_dbus_message_builder *builder = user_data;
const char* macstr;
if (!sta->authenticated)
return;
macstr = util_address_to_string(sta->addr);
l_dbus_message_builder_append_basic(builder, 's', macstr);
}
static bool adhoc_property_get_peers(struct l_dbus *dbus,
struct l_dbus_message *message,
struct l_dbus_message_builder *builder,
void *user_data)
{
struct adhoc_state *adhoc = user_data;
l_dbus_message_builder_enter_array(builder, "s");
l_queue_foreach(adhoc->sta_states, sta_append, builder);
l_dbus_message_builder_leave_array(builder);
return true;
}
static bool adhoc_property_get_started(struct l_dbus *dbus,
struct l_dbus_message *message,
struct l_dbus_message_builder *builder,
void *user_data)
{
struct adhoc_state *adhoc = user_data;
bool started = adhoc->started;
l_dbus_message_builder_append_basic(builder, 'b', &started);
return true;
}
static void adhoc_setup_interface(struct l_dbus_interface *interface)
{
l_dbus_interface_method(interface, "Start", 0, adhoc_dbus_start, "",
"ss", "ssid", "wpa2_psk");
l_dbus_interface_method(interface, "Stop", 0, adhoc_dbus_stop, "", "");
l_dbus_interface_method(interface, "StartOpen", 0,
adhoc_dbus_start_open, "", "s", "ssid");
l_dbus_interface_property(interface, "ConnectedPeers", 0, "as",
adhoc_property_get_peers, NULL);
l_dbus_interface_property(interface, "Started", 0, "b",
adhoc_property_get_started, NULL);
}
static void adhoc_destroy_interface(void *user_data)
{
struct adhoc_state *adhoc = user_data;
adhoc_free(adhoc);
}
static void adhoc_add_interface(struct netdev *netdev)
{
struct adhoc_state *adhoc;
/* just allocate/set device, Start method will complete setup */
adhoc = l_new(struct adhoc_state, 1);
adhoc->netdev = netdev;
adhoc->nl80211 = l_genl_family_new(iwd_get_genl(), NL80211_GENL_NAME);
/* setup adhoc dbus interface */
l_dbus_object_add_interface(dbus_get_bus(),
netdev_get_path(netdev), IWD_ADHOC_INTERFACE, adhoc);
}
static void adhoc_remove_interface(struct netdev *netdev)
{
l_dbus_object_remove_interface(dbus_get_bus(),
netdev_get_path(netdev), IWD_ADHOC_INTERFACE);
}
static void adhoc_netdev_watch(struct netdev *netdev,
enum netdev_watch_event event, void *userdata)
{
switch (event) {
case NETDEV_WATCH_EVENT_UP:
case NETDEV_WATCH_EVENT_NEW:
if (netdev_get_iftype(netdev) == NETDEV_IFTYPE_ADHOC &&
netdev_get_is_up(netdev))
adhoc_add_interface(netdev);
break;
case NETDEV_WATCH_EVENT_DOWN:
case NETDEV_WATCH_EVENT_DEL:
adhoc_remove_interface(netdev);
break;
default:
break;
}
}
static int adhoc_init(void)
{
netdev_watch = netdev_watch_add(adhoc_netdev_watch, NULL, NULL);
l_dbus_register_interface(dbus_get_bus(), IWD_ADHOC_INTERFACE,
adhoc_setup_interface, adhoc_destroy_interface, false);
return 0;
}
static void adhoc_exit(void)
{
netdev_watch_remove(netdev_watch);
l_dbus_unregister_interface(dbus_get_bus(), IWD_ADHOC_INTERFACE);
}
IWD_MODULE(adhoc, adhoc_init, adhoc_exit)
IWD_MODULE_DEPENDS(adhoc, netdev);