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mirror of https://git.kernel.org/pub/scm/network/wireless/iwd.git synced 2024-11-22 14:49:24 +01:00

device: In roam, preauthenticate to target BSS if supported

If FT is not possible and we're using 8021x try to preauthenticate to
target BSS before reassociation to it.
This commit is contained in:
Andrew Zaborowski 2017-04-29 03:53:28 +02:00 committed by Denis Kenzior
parent 08e863cb7e
commit a620a02d35

View File

@ -76,6 +76,7 @@ struct device {
struct timespec roam_min_time;
struct l_timeout *roam_trigger_timeout;
uint32_t roam_scan_id;
uint8_t preauth_bssid[ETH_ALEN];
struct wiphy *wiphy;
struct netdev *netdev;
@ -802,11 +803,102 @@ static void device_fast_transition_cb(struct netdev *netdev,
device_roam_failed(device);
}
static void device_transition_reassociate(struct device *device,
struct scan_bss *bss,
struct handshake_state *new_hs)
{
if (netdev_reassociate(device->netdev, bss, new_hs,
device_reassociate_cb) < 0) {
handshake_state_free(new_hs);
device_roam_failed(device);
return;
}
device->connected_bss = bss;
device->preparing_roam = false;
device_enter_state(device, DEVICE_STATE_ROAMING);
}
static bool bss_match_bssid(const void *a, const void *b)
{
const struct scan_bss *bss = a;
const uint8_t *bssid = b;
return !memcmp(bss->addr, bssid, sizeof(bss->addr));
}
static void device_preauthenticate_cb(struct netdev *netdev,
enum netdev_result result,
const uint8_t *pmk, void *user_data)
{
struct device *device = user_data;
struct scan_bss *bss;
struct handshake_state *new_hs;
l_debug("%d, result: %d", device->index, result);
if (!device->preparing_roam || result == NETDEV_RESULT_ABORTED)
return;
bss = l_queue_find(device->bss_list, bss_match_bssid,
device->preauth_bssid);
if (!bss) {
l_error("Roam target BSS not found");
device_roam_failed(device);
return;
}
new_hs = device_handshake_setup(device, device->connected_network, bss);
if (!new_hs) {
l_error("device_handshake_setup failed");
device_roam_failed(device);
return;
}
if (result == NETDEV_RESULT_OK) {
uint8_t pmkid[16];
uint8_t rsne_buf[300];
struct ie_rsn_info rsn_info;
handshake_state_set_pmk(new_hs, pmk);
handshake_state_set_authenticator_address(new_hs,
device->preauth_bssid);
handshake_state_set_supplicant_address(new_hs,
netdev_get_address(device->netdev));
/*
* Rebuild the RSNE to include the negotiated PMKID. Note
* own_ie can't be a WPA IE here, including because the
* WPA IE doesn't have a capabilities field and
* target_rsne->preauthentication would have been false in
* device_transition_start.
*/
ie_parse_rsne_from_data(new_hs->own_ie, new_hs->own_ie[1] + 2,
&rsn_info);
handshake_state_get_pmkid(new_hs, pmkid);
rsn_info.num_pmkids = 1;
rsn_info.pmkids = pmkid;
ie_build_rsne(&rsn_info, rsne_buf);
handshake_state_set_own_rsn(new_hs, rsne_buf);
}
device_transition_reassociate(device, bss, new_hs);
}
static void device_transition_start(struct device *device, struct scan_bss *bss)
{
struct handshake_state *hs = netdev_get_handshake(device->netdev);
uint16_t mdid;
struct handshake_state *new_hs;
struct ie_rsn_info cur_rsne, target_rsne;
enum security security =
network_get_security(device->connected_network);
l_debug("%d, target %s", device->index,
util_address_to_string(bss->addr));
@ -842,6 +934,35 @@ static void device_transition_start(struct device *device, struct scan_bss *bss)
/* Non-FT transition */
/*
* FT not available, we can try preauthentication if available.
* 802.11-2012 section 11.5.9.2:
* "A STA shall not use preauthentication within the same mobility
* domain if AKM suite type 00-0F-AC:3 or 00-0F-AC:4 is used in
* the current association."
*/
if (security == SECURITY_8021X &&
scan_bss_get_rsn_info(device->connected_bss,
&cur_rsne) >= 0 &&
scan_bss_get_rsn_info(bss, &target_rsne) >= 0 &&
cur_rsne.preauthentication &&
target_rsne.preauthentication) {
/*
* Both the current and the target AP support
* pre-authentication and we're using 8021x authentication so
* attempt to pre-authenticate and reassociate afterwards.
* If the pre-authentication fails or times out we simply
* won't supply any PMKID when reassociating.
* Remain in the preparing_roam state.
*/
memcpy(device->preauth_bssid, bss->addr, ETH_ALEN);
if (netdev_preauthenticate(device->netdev, bss,
device_preauthenticate_cb,
device) >= 0)
return;
}
new_hs = device_handshake_setup(device, device->connected_network, bss);
if (!new_hs) {
l_error("device_handshake_setup failed in reassociation");
@ -850,17 +971,7 @@ static void device_transition_start(struct device *device, struct scan_bss *bss)
return;
}
if (netdev_reassociate(device->netdev, bss, new_hs,
device_reassociate_cb) < 0) {
handshake_state_free(new_hs);
device_roam_failed(device);
return;
}
device->connected_bss = bss;
device->preparing_roam = false;
device_enter_state(device, DEVICE_STATE_ROAMING);
device_transition_reassociate(device, bss, new_hs);
}
static void device_roam_scan_triggered(int err, void *user_data)