events.c

WPA在Linux下实现的原代码 WPA在Linux下实现的原代码

				continue;
			}
			if (wpa_supplicant_ssid_bss_match(ssid, bss)) {
				selected = bss;
				*selected_ssid = ssid;
				break;
			}
		}
	}

	/* If no WPA-enabled AP found, try to find non-WPA AP, if configuration
	 * allows this. */
	for (i = 0; i < num && !selected; i++) {
		bss = &results[i];
		if ((e = wpa_blacklist_get(wpa_s, bss->bssid)) &&
		    e->count > 1) {
			continue;
		}
		for (ssid = group; ssid; ssid = ssid->pnext) {
			if (!ssid->disabled &&
			    (ssid->ssid_len == 0 ||
			     (bss->ssid_len == ssid->ssid_len &&
			      memcmp(bss->ssid, ssid->ssid, bss->ssid_len) ==
			      0)) &&
			    (!ssid->bssid_set ||
			     memcmp(bss->bssid, ssid->bssid, ETH_ALEN) == 0) &&
			    ((ssid->key_mgmt & WPA_KEY_MGMT_NONE) ||
			     (ssid->key_mgmt & WPA_KEY_MGMT_IEEE8021X_NO_WPA))
			    &&
			    (!(ssid->key_mgmt &
			       (WPA_KEY_MGMT_IEEE8021X | WPA_KEY_MGMT_PSK)) ||
			     (bss->wpa_ie_len == 0 && bss->rsn_ie_len == 0)) &&
			    wpa_supplicant_match_privacy(bss, ssid) &&
			    !(bss->caps & IEEE80211_CAP_IBSS))
			{
				selected = bss;
				*selected_ssid = ssid;
				wpa_printf(MSG_DEBUG, "   selected non-WPA AP "
					   MACSTR " ssid='%s'",
					   MAC2STR(bss->bssid),
					   wpa_ssid_txt(bss->ssid,
							bss->ssid_len));
				break;
			}
		}
	}

	return selected;
}


static void wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s)
{
	int num, prio;
	struct wpa_scan_result *selected = NULL;
	struct wpa_ssid *ssid = NULL;
	struct wpa_scan_result *results;

	if (wpa_supplicant_get_scan_results(wpa_s) < 0) {
		if (wpa_s->conf->ap_scan == 2)
			return;
		wpa_printf(MSG_DEBUG, "Failed to get scan results - try "
			   "scanning again");
		wpa_supplicant_req_scan(wpa_s, 1, 0);
		return;
	}
	if (wpa_s->conf->ap_scan == 2 || wpa_s->disconnected)
		return;
	results = wpa_s->scan_results;
	num = wpa_s->num_scan_results;

	while (selected == NULL) {
		for (prio = 0; prio < wpa_s->conf->num_prio; prio++) {
			selected = wpa_supplicant_select_bss(
				wpa_s, wpa_s->conf->pssid[prio], results, num,
				&ssid);
			if (selected)
				break;
		}

		if (selected == NULL && wpa_s->blacklist) {
			wpa_printf(MSG_DEBUG, "No APs found - clear blacklist "
				   "and try again");
			wpa_blacklist_clear(wpa_s);
		} else if (selected == NULL) {
			break;
		}
	}

	if (selected) {
		if (wpa_s->reassociate ||
		    memcmp(selected->bssid, wpa_s->bssid, ETH_ALEN) != 0) {
			if (wpa_supplicant_scard_init(wpa_s, ssid)) {
				wpa_supplicant_req_scan(wpa_s, 10, 0);
				return;
			}
			wpa_supplicant_associate(wpa_s, selected, ssid);
		} else {
			wpa_printf(MSG_DEBUG, "Already associated with the "
				   "selected AP.");
		}
		rsn_preauth_scan_results(wpa_s->wpa, results, num);
	} else {
		wpa_printf(MSG_DEBUG, "No suitable AP found.");
		wpa_supplicant_req_scan(wpa_s, 5, 0);
	}
}


static void wpa_supplicant_event_associnfo(struct wpa_supplicant *wpa_s,
					   union wpa_event_data *data)
{
	int l, len, found = 0, wpa_found, rsn_found;
	u8 *p;

	wpa_printf(MSG_DEBUG, "Association info event");
	if (data->assoc_info.req_ies)
		wpa_hexdump(MSG_DEBUG, "req_ies", data->assoc_info.req_ies,
			    data->assoc_info.req_ies_len);
	if (data->assoc_info.resp_ies)
		wpa_hexdump(MSG_DEBUG, "resp_ies", data->assoc_info.resp_ies,
			    data->assoc_info.resp_ies_len);
	if (data->assoc_info.beacon_ies)
		wpa_hexdump(MSG_DEBUG, "beacon_ies",
			    data->assoc_info.beacon_ies,
			    data->assoc_info.beacon_ies_len);

	p = data->assoc_info.req_ies;
	l = data->assoc_info.req_ies_len;

	/* Go through the IEs and make a copy of the WPA/RSN IE, if present. */
	while (p && l >= 2) {
		len = p[1] + 2;
		if (len > l) {
			wpa_hexdump(MSG_DEBUG, "Truncated IE in assoc_info",
				    p, l);
			break;
		}
		if ((p[0] == GENERIC_INFO_ELEM && p[1] >= 6 &&
		     (memcmp(&p[2], "\x00\x50\xF2\x01\x01\x00", 6) == 0)) ||
		    (p[0] == RSN_INFO_ELEM && p[1] >= 2)) {
			if (wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, p, len))
				break;
			found = 1;
			wpa_find_assoc_pmkid(wpa_s);
			break;
		}
		l -= len;
		p += len;
	}
	if (!found && data->assoc_info.req_ies)
		wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, NULL, 0);

	/* WPA/RSN IE from Beacon/ProbeResp */
	p = data->assoc_info.beacon_ies;
	l = data->assoc_info.beacon_ies_len;

	/* Go through the IEs and make a copy of the WPA/RSN IEs, if present.
	 */
	wpa_found = rsn_found = 0;
	while (p && l >= 2) {
		len = p[1] + 2;
		if (len > l) {
			wpa_hexdump(MSG_DEBUG, "Truncated IE in beacon_ies",
				    p, l);
			break;
		}
		if (!wpa_found &&
		    p[0] == GENERIC_INFO_ELEM && p[1] >= 6 &&
		    memcmp(&p[2], "\x00\x50\xF2\x01\x01\x00", 6) == 0) {
			wpa_found = 1;
			wpa_sm_set_ap_wpa_ie(wpa_s->wpa, p, len);
		}

		if (!rsn_found &&
		    p[0] == RSN_INFO_ELEM && p[1] >= 2) {
			rsn_found = 1;
			wpa_sm_set_ap_rsn_ie(wpa_s->wpa, p, len);
		}

		l -= len;
		p += len;
	}

	if (!wpa_found && data->assoc_info.beacon_ies)
		wpa_sm_set_ap_wpa_ie(wpa_s->wpa, NULL, 0);
	if (!rsn_found && data->assoc_info.beacon_ies)
		wpa_sm_set_ap_rsn_ie(wpa_s->wpa, NULL, 0);
}


static void wpa_supplicant_event_assoc(struct wpa_supplicant *wpa_s,
				       union wpa_event_data *data)
{
	u8 bssid[ETH_ALEN];

	if (data)
		wpa_supplicant_event_associnfo(wpa_s, data);

	wpa_supplicant_set_state(wpa_s, WPA_ASSOCIATED);
	if (wpa_drv_get_bssid(wpa_s, bssid) >= 0 &&
	    memcmp(bssid, wpa_s->bssid, ETH_ALEN) != 0) {
		wpa_msg(wpa_s, MSG_DEBUG, "Associated to a new BSS: BSSID="
			MACSTR, MAC2STR(bssid));
		memcpy(wpa_s->bssid, bssid, ETH_ALEN);
		if (wpa_supplicant_dynamic_keys(wpa_s)) {
			wpa_clear_keys(wpa_s, bssid);
		}
		if (wpa_supplicant_select_config(wpa_s) < 0) {
			wpa_supplicant_disassociate(wpa_s,
						    REASON_DEAUTH_LEAVING);
			return;
		}
	}

	wpa_msg(wpa_s, MSG_INFO, "Associated with " MACSTR, MAC2STR(bssid));
	if (wpa_s->current_ssid) {
		/* When using scanning (ap_scan=1), SIM PC/SC interface can be
		 * initialized before association, but for other modes,
		 * initialize PC/SC here, if the current configuration needs
		 * smartcard or SIM/USIM. */
		wpa_supplicant_scard_init(wpa_s, wpa_s->current_ssid);
	}
	wpa_sm_notify_assoc(wpa_s->wpa, bssid);
	l2_packet_notify_auth_start(wpa_s->l2);

	/*
	 * Set portEnabled first to FALSE in order to get EAP state machine out
	 * of the SUCCESS state and eapSuccess cleared. Without this, EAPOL PAE
	 * state machine may transit to AUTHENTICATING state based on obsolete
	 * eapSuccess and then trigger BE_AUTH to SUCCESS and PAE to
	 * AUTHENTICATED without ever giving chance to EAP state machine to
	 * reset the state.
	 */
	eapol_sm_notify_portEnabled(wpa_s->eapol, FALSE);
	eapol_sm_notify_portValid(wpa_s->eapol, FALSE);
	if (wpa_s->key_mgmt == WPA_KEY_MGMT_PSK)
		eapol_sm_notify_eap_success(wpa_s->eapol, FALSE);
	/* 802.1X::portControl = Auto */
	eapol_sm_notify_portEnabled(wpa_s->eapol, TRUE);
	wpa_s->eapol_received = 0;
	if (wpa_s->key_mgmt == WPA_KEY_MGMT_NONE ||
	    wpa_s->key_mgmt == WPA_KEY_MGMT_WPA_NONE) {
		wpa_supplicant_cancel_auth_timeout(wpa_s);
		wpa_supplicant_set_state(wpa_s, WPA_COMPLETED);
	} else {
		/* Timeout for receiving the first EAPOL packet */
		wpa_supplicant_req_auth_timeout(wpa_s, 10, 0);
	}
	wpa_supplicant_cancel_scan(wpa_s);
}


static void wpa_supplicant_event_disassoc(struct wpa_supplicant *wpa_s)
{
	if (wpa_s->key_mgmt == WPA_KEY_MGMT_WPA_NONE) {
		/*
		 * At least Host AP driver and a Prism3 card seemed to be
		 * generating streams of disconnected events when configuring
		 * IBSS for WPA-None. Ignore them for now.
		 */
		wpa_printf(MSG_DEBUG, "Disconnect event - ignore in "
			   "IBSS/WPA-None mode");
		return;
	}

	if (wpa_s->wpa_state == WPA_4WAY_HANDSHAKE &&
	    wpa_s->key_mgmt == WPA_KEY_MGMT_PSK) {
		wpa_msg(wpa_s, MSG_INFO, "WPA: 4-Way Handshake failed - "
			"pre-shared key may be incorrect");
	}
	if (wpa_s->wpa_state >= WPA_ASSOCIATED)
		wpa_supplicant_req_scan(wpa_s, 0, 100000);
	wpa_blacklist_add(wpa_s, wpa_s->bssid);
	wpa_sm_notify_disassoc(wpa_s->wpa);
	wpa_msg(wpa_s, MSG_INFO, WPA_EVENT_DISCONNECTED "- Disconnect event - "
		"remove keys");
	if (wpa_supplicant_dynamic_keys(wpa_s)) {
		wpa_s->keys_cleared = 0;
		wpa_clear_keys(wpa_s, wpa_s->bssid);
	}
	wpa_supplicant_mark_disassoc(wpa_s);
}


static void
wpa_supplicant_event_michael_mic_failure(struct wpa_supplicant *wpa_s,
					 union wpa_event_data *data)
{
	int pairwise;
	time_t now;

	wpa_msg(wpa_s, MSG_WARNING, "Michael MIC failure detected");
	pairwise = (data && data->michael_mic_failure.unicast);
	wpa_sm_key_request(wpa_s->wpa, 1, pairwise);
	time(&now);
	if (wpa_s->last_michael_mic_error &&
	    now - wpa_s->last_michael_mic_error <= 60) {
		/* initialize countermeasures */
		wpa_s->countermeasures = 1;
		wpa_msg(wpa_s, MSG_WARNING, "TKIP countermeasures started");

		/*
		 * Need to wait for completion of request frame. We do not get
		 * any callback for the message completion, so just wait a
		 * short while and hope for the best. */
		usleep(10000);

		wpa_drv_set_countermeasures(wpa_s, 1);
		wpa_supplicant_deauthenticate(wpa_s,
					      REASON_MICHAEL_MIC_FAILURE);
		eloop_cancel_timeout(wpa_supplicant_stop_countermeasures,
				     wpa_s, NULL);
		eloop_register_timeout(60, 0,
				       wpa_supplicant_stop_countermeasures,
				       wpa_s, NULL);
		/* TODO: mark the AP rejected for 60 second. STA is
		 * allowed to associate with another AP.. */
	}
	wpa_s->last_michael_mic_error = now;
}


static void
wpa_supplicant_event_interface_status(struct wpa_supplicant *wpa_s,
				      union wpa_event_data *data)
{
	if (strcmp(wpa_s->ifname, data->interface_status.ifname) != 0)
		return;

	switch (data->interface_status.ievent) {
	case EVENT_INTERFACE_ADDED:
		if (!wpa_s->interface_removed)
			break;
		wpa_s->interface_removed = 0;
		wpa_printf(MSG_DEBUG, "Configured interface was added.");
		if (wpa_supplicant_driver_init(wpa_s, 1) < 0) {
			wpa_printf(MSG_INFO, "Failed to initialize the driver "
				   "after interface was added.");
		}
		break;
	case EVENT_INTERFACE_REMOVED:
		wpa_printf(MSG_DEBUG, "Configured interface was removed.");
		wpa_s->interface_removed = 1;
		wpa_supplicant_mark_disassoc(wpa_s);
		l2_packet_deinit(wpa_s->l2);
		wpa_s->l2 = NULL;
		break;
	}
}


void wpa_supplicant_event(struct wpa_supplicant *wpa_s, wpa_event_type event,
			  union wpa_event_data *data)
{
	switch (event) {
	case EVENT_ASSOC:
		wpa_supplicant_event_assoc(wpa_s, data);
		break;
	case EVENT_DISASSOC:
		wpa_supplicant_event_disassoc(wpa_s);
		break;
	case EVENT_MICHAEL_MIC_FAILURE:
		wpa_supplicant_event_michael_mic_failure(wpa_s, data);
		break;
	case EVENT_SCAN_RESULTS:
		wpa_supplicant_event_scan_results(wpa_s);
		break;
	case EVENT_ASSOCINFO:
		wpa_supplicant_event_associnfo(wpa_s, data);
		break;
	case EVENT_INTERFACE_STATUS:
		wpa_supplicant_event_interface_status(wpa_s, data);
		break;
	case EVENT_PMKID_CANDIDATE:
		wpa_supplicant_event_pmkid_candidate(wpa_s, data);
		break;
	default:
		wpa_printf(MSG_INFO, "Unknown event %d", event);
		break;
	}
}