DGNum/hostapd
6
0
Fork 0
Code Issues Pull requests 1 Projects Releases Packages Wiki Activity Actions

IBSS RSN: Work around Data RX vs. Authentication RX race condition

Browse source 
It is possible for the driver to report EAPOL frame RX before
Authentication frame RX even if the frames arrived in the opposite
order. This can result in issues in cases where both IBSS peers initiate
Authentication frame exchange at about the same time and one of the
EAPOL sessions is started before processing Authentication frame seq=1
RX. Work around this by not re-initializing EAPOL state on
Authentication (SEQ=1) RX if own Authentication frame was transmitted
within last 500 ms.

Signed-hostap: Jouni Malinen <j@w1.fi>
This commit is contained in:
Jouni Malinen 2013-08-27 02:54:35 +03:00
parent 3d5b356ac0
commit 6fb7b58fe4
2 changed files with 15 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

13
wpa_supplicant/ibss_rsn.c
View file

@ -566,6 +566,8 @@ int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
*/
peer->authentication_status |= IBSS_RSN_AUTH_BY_US;
return ibss_rsn_auth_init(ibss_rsn, peer);
} else {
os_get_time(&peer->own_auth_tx);
}
return 0;
@ -807,6 +809,16 @@ static void ibss_rsn_handle_auth_1_of_2(struct ibss_rsn *ibss_rsn,
if (peer &&
peer->authentication_status & IBSS_RSN_AUTH_EAPOL_BY_PEER) {
if (peer->own_auth_tx.sec) {
struct os_time now, diff;
os_get_time(&now);
os_time_sub(&now, &peer->own_auth_tx, &diff);
if (diff.sec == 0 && diff.usec < 500000) {
wpa_printf(MSG_DEBUG, "RSN: Skip IBSS reinit since only %u usec from own Auth frame TX",
(int) diff.usec);
goto skip_reinit;
}
}
/*
* A peer sent us an Authentication frame even though it already
* started an EAPOL session. We should reinit state machines
@ -829,6 +841,7 @@ static void ibss_rsn_handle_auth_1_of_2(struct ibss_rsn *ibss_rsn,
MAC2STR(addr));
}
skip_reinit:
/* reply with an Authentication frame now, before sending an EAPOL */
ibss_rsn_send_auth(ibss_rsn, addr, 2);
/* no need to start another AUTH challenge in the other way.. */

2
wpa_supplicant/ibss_rsn.h
View file

@ -39,6 +39,8 @@ struct ibss_rsn_peer {
struct wpa_state_machine *auth;
int authentication_status;
struct os_time own_auth_tx;
};
struct ibss_rsn {