Fix fallback from failed PMKSA caching into full EAP authentication (DO NOT MERGE)

Commit 83935317a78fb4157eb6e5134527b9311dbf7b8c added forced
disconnection in case of 4-way handshake failures. However, it should
not have changed the case where the supplicant is requesting fallback
to full EAP authentication if the PMKID in EAPOL-Key message 1/4 is
not know. This case needs to send an EAPOL-Start frame instead of
EAPOL-Key message 2/4.

This works around a problem with APs that try to force PMKSA caching
even when the client does not include PMKID in (re)association request
frame to request it. [Bug 355]

Change-Id: Ib0175ccddbc961583b2662abc1e21c95927b084a
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>

diff --git a/wpa_supplicant/src/rsn_supp/wpa.c b/wpa_supplicant/src/rsn_supp/wpa.c
index f73a770..33e558c 100644 (file)
--- a/wpa_supplicant/src/rsn_supp/wpa.c
+++ b/wpa_supplicant/src/rsn_supp/wpa.c
@@ -285,6 +285,7 @@ static int wpa_supplicant_get_pmk(struct wpa_sm *sm,
                        wpa_sm_ether_send(sm, sm->bssid, ETH_P_EAPOL,
                                          buf, buflen);
                        os_free(buf);
+                       return -2;
                }
 
                return -1;
@@ -380,6 +381,7 @@ static void wpa_supplicant_process_1_of_4(struct wpa_sm *sm,
        struct wpa_eapol_ie_parse ie;
        struct wpa_ptk *ptk;
        u8 buf[8];
+       int res;
 
        if (wpa_sm_get_network_ctx(sm) == NULL) {
                wpa_printf(MSG_WARNING, "WPA: No SSID info found (msg 1 of "
@@ -407,7 +409,13 @@ static void wpa_supplicant_process_1_of_4(struct wpa_sm *sm,
        }
 #endif /* CONFIG_NO_WPA2 */
 
-       if (wpa_supplicant_get_pmk(sm, src_addr, ie.pmkid))
+       res = wpa_supplicant_get_pmk(sm, src_addr, ie.pmkid);
+       if (res == -2) {
+               wpa_printf(MSG_DEBUG, "RSN: Do not reply to msg 1/4 - "
+                          "requesting full EAP authentication");
+               return;
+       }
+       if (res)
                goto failed;
 
        if (sm->renew_snonce) {