mlme.c

WLAN无线网络管理的最新程序

			pos = buf + len;
			len++;
			esupp_rates[1]++;
		} else if (supp_rates[1] == 8) {
			esupp_rates = pos;
			esupp_rates[0] = WLAN_EID_EXT_SUPP_RATES;
			esupp_rates[1] = 1;
			pos = &esupp_rates[2];
		} else {
			pos = buf + len;
			len++;
			supp_rates[1]++;
		}
		*pos = rate->rate / 5;
	}

	ieee80211_sta_tx(wpa_s, buf, len);
	os_free(buf);
}


static int ieee80211_sta_wep_configured(struct wpa_supplicant *wpa_s)
{
#if 0 /* FIX */
	if (sdata == NULL || sdata->default_key == NULL ||
	    sdata->default_key->alg != ALG_WEP)
		return 0;
	return 1;
#else
	return 0;
#endif
}


static void ieee80211_auth_completed(struct wpa_supplicant *wpa_s)
{
	wpa_printf(MSG_DEBUG, "MLME: authenticated");
	wpa_s->mlme.authenticated = 1;
	ieee80211_associate(wpa_s);
}


static void ieee80211_auth_challenge(struct wpa_supplicant *wpa_s,
				     struct ieee80211_mgmt *mgmt,
				     size_t len,
				     struct ieee80211_rx_status *rx_status)
{
	u8 *pos;
	struct ieee802_11_elems elems;

	wpa_printf(MSG_DEBUG, "MLME: replying to auth challenge");
	pos = mgmt->u.auth.variable;
	if (ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems)
	    == ParseFailed) {
		wpa_printf(MSG_DEBUG, "MLME: failed to parse Auth(challenge)");
		return;
	}
	if (elems.challenge == NULL) {
		wpa_printf(MSG_DEBUG, "MLME: no challenge IE in shared key "
			   "auth frame");
		return;
	}
	ieee80211_send_auth(wpa_s, 3, elems.challenge - 2,
			    elems.challenge_len + 2, 1);
}


static void ieee80211_rx_mgmt_auth(struct wpa_supplicant *wpa_s,
				   struct ieee80211_mgmt *mgmt,
				   size_t len,
				   struct ieee80211_rx_status *rx_status)
{
	struct wpa_ssid *ssid = wpa_s->current_ssid;
	u16 auth_alg, auth_transaction, status_code;
	int adhoc;

	adhoc = ssid && ssid->mode == 1;

	if (wpa_s->mlme.state != IEEE80211_AUTHENTICATE && !adhoc) {
		wpa_printf(MSG_DEBUG, "MLME: authentication frame received "
			   "from " MACSTR ", but not in authenticate state - "
			   "ignored", MAC2STR(mgmt->sa));
		return;
	}

	if (len < 24 + 6) {
		wpa_printf(MSG_DEBUG, "MLME: too short (%lu) authentication "
			   "frame received from " MACSTR " - ignored",
			   (unsigned long) len, MAC2STR(mgmt->sa));
		return;
	}

	if (!adhoc && os_memcmp(wpa_s->bssid, mgmt->sa, ETH_ALEN) != 0) {
		wpa_printf(MSG_DEBUG, "MLME: authentication frame received "
			   "from unknown AP (SA=" MACSTR " BSSID=" MACSTR
			   ") - ignored",
			   MAC2STR(mgmt->sa), MAC2STR(mgmt->bssid));
		return;
	}

	if (adhoc && os_memcmp(wpa_s->bssid, mgmt->bssid, ETH_ALEN) != 0) {
		wpa_printf(MSG_DEBUG, "MLME: authentication frame received "
			   "from unknown BSSID (SA=" MACSTR " BSSID=" MACSTR
			   ") - ignored",
			   MAC2STR(mgmt->sa), MAC2STR(mgmt->bssid));
		return;
	}

	auth_alg = le_to_host16(mgmt->u.auth.auth_alg);
	auth_transaction = le_to_host16(mgmt->u.auth.auth_transaction);
	status_code = le_to_host16(mgmt->u.auth.status_code);

	wpa_printf(MSG_DEBUG, "MLME: RX authentication from " MACSTR
		   " (alg=%d transaction=%d status=%d)",
		   MAC2STR(mgmt->sa), auth_alg, auth_transaction, status_code);

	if (adhoc) {
		/* IEEE 802.11 standard does not require authentication in IBSS
		 * networks and most implementations do not seem to use it.
		 * However, try to reply to authentication attempts if someone
		 * has actually implemented this.
		 * TODO: Could implement shared key authentication. */
		if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) {
			wpa_printf(MSG_DEBUG, "MLME: unexpected IBSS "
				   "authentication frame (alg=%d "
				   "transaction=%d)",
				   auth_alg, auth_transaction);
			return;
		}
		ieee80211_send_auth(wpa_s, 2, NULL, 0, 0);
	}

	if (auth_alg != wpa_s->mlme.auth_alg ||
	    auth_transaction != wpa_s->mlme.auth_transaction) {
		wpa_printf(MSG_DEBUG, "MLME: unexpected authentication frame "
			   "(alg=%d transaction=%d)",
			   auth_alg, auth_transaction);
		return;
	}

	if (status_code != WLAN_STATUS_SUCCESS) {
		wpa_printf(MSG_DEBUG, "MLME: AP denied authentication "
			   "(auth_alg=%d code=%d)", wpa_s->mlme.auth_alg,
			   status_code);
		if (status_code == WLAN_STATUS_NOT_SUPPORTED_AUTH_ALG) {
			const int num_algs = 3;
			u8 algs[num_algs];
			int i, pos;
			algs[0] = algs[1] = algs[2] = 0xff;
			if (wpa_s->mlme.auth_algs & IEEE80211_AUTH_ALG_OPEN)
				algs[0] = WLAN_AUTH_OPEN;
			if (wpa_s->mlme.auth_algs &
			    IEEE80211_AUTH_ALG_SHARED_KEY)
				algs[1] = WLAN_AUTH_SHARED_KEY;
			if (wpa_s->mlme.auth_algs & IEEE80211_AUTH_ALG_LEAP)
				algs[2] = WLAN_AUTH_LEAP;
			if (wpa_s->mlme.auth_alg == WLAN_AUTH_OPEN)
				pos = 0;
			else if (wpa_s->mlme.auth_alg == WLAN_AUTH_SHARED_KEY)
				pos = 1;
			else
				pos = 2;
			for (i = 0; i < num_algs; i++) {
				pos++;
				if (pos >= num_algs)
					pos = 0;
				if (algs[pos] == wpa_s->mlme.auth_alg ||
				    algs[pos] == 0xff)
					continue;
				if (algs[pos] == WLAN_AUTH_SHARED_KEY &&
				    !ieee80211_sta_wep_configured(wpa_s))
					continue;
				wpa_s->mlme.auth_alg = algs[pos];
				wpa_printf(MSG_DEBUG, "MLME: set auth_alg=%d "
					   "for next try",
					   wpa_s->mlme.auth_alg);
				break;
			}
		}
		return;
	}

	switch (wpa_s->mlme.auth_alg) {
	case WLAN_AUTH_OPEN:
	case WLAN_AUTH_LEAP:
		ieee80211_auth_completed(wpa_s);
		break;
	case WLAN_AUTH_SHARED_KEY:
		if (wpa_s->mlme.auth_transaction == 4)
			ieee80211_auth_completed(wpa_s);
		else
			ieee80211_auth_challenge(wpa_s, mgmt, len,
						 rx_status);
		break;
	}
}


static void ieee80211_rx_mgmt_deauth(struct wpa_supplicant *wpa_s,
				     struct ieee80211_mgmt *mgmt,
				     size_t len,
				     struct ieee80211_rx_status *rx_status)
{
	u16 reason_code;

	if (len < 24 + 2) {
		wpa_printf(MSG_DEBUG, "MLME: too short (%lu) deauthentication "
			   "frame received from " MACSTR " - ignored",
			   (unsigned long) len, MAC2STR(mgmt->sa));
		return;
	}

	if (os_memcmp(wpa_s->bssid, mgmt->sa, ETH_ALEN) != 0) {
		wpa_printf(MSG_DEBUG, "MLME: deauthentication frame received "
			   "from unknown AP (SA=" MACSTR " BSSID=" MACSTR
			   ") - ignored",
			   MAC2STR(mgmt->sa), MAC2STR(mgmt->bssid));
		return;
	}

	reason_code = le_to_host16(mgmt->u.deauth.reason_code);

	wpa_printf(MSG_DEBUG, "MLME: RX deauthentication from " MACSTR
		   " (reason=%d)", MAC2STR(mgmt->sa), reason_code);

	if (wpa_s->mlme.authenticated)
		wpa_printf(MSG_DEBUG, "MLME: deauthenticated");

	if (wpa_s->mlme.state == IEEE80211_AUTHENTICATE ||
	    wpa_s->mlme.state == IEEE80211_ASSOCIATE ||
	    wpa_s->mlme.state == IEEE80211_ASSOCIATED) {
		wpa_s->mlme.state = IEEE80211_AUTHENTICATE;
		ieee80211_reschedule_timer(wpa_s,
					   IEEE80211_RETRY_AUTH_INTERVAL);
	}

	ieee80211_set_associated(wpa_s, 0);
	wpa_s->mlme.authenticated = 0;
}


static void ieee80211_rx_mgmt_disassoc(struct wpa_supplicant *wpa_s,
				       struct ieee80211_mgmt *mgmt,
				       size_t len,
				       struct ieee80211_rx_status *rx_status)
{
	u16 reason_code;

	if (len < 24 + 2) {
		wpa_printf(MSG_DEBUG, "MLME: too short (%lu) disassociation "
			   "frame received from " MACSTR " - ignored",
			   (unsigned long) len, MAC2STR(mgmt->sa));
		return;
	}

	if (os_memcmp(wpa_s->bssid, mgmt->sa, ETH_ALEN) != 0) {
		wpa_printf(MSG_DEBUG, "MLME: disassociation frame received "
			   "from unknown AP (SA=" MACSTR " BSSID=" MACSTR
			   ") - ignored",
			   MAC2STR(mgmt->sa), MAC2STR(mgmt->bssid));
		return;
	}

	reason_code = le_to_host16(mgmt->u.disassoc.reason_code);

	wpa_printf(MSG_DEBUG, "MLME: RX disassociation from " MACSTR
		   " (reason=%d)", MAC2STR(mgmt->sa), reason_code);

	if (wpa_s->mlme.associated)
		wpa_printf(MSG_DEBUG, "MLME: disassociated");

	if (wpa_s->mlme.state == IEEE80211_ASSOCIATED) {
		wpa_s->mlme.state = IEEE80211_ASSOCIATE;
		ieee80211_reschedule_timer(wpa_s,
					   IEEE80211_RETRY_AUTH_INTERVAL);
	}

	ieee80211_set_associated(wpa_s, 0);
}


static void ieee80211_rx_mgmt_assoc_resp(struct wpa_supplicant *wpa_s,
					 struct ieee80211_mgmt *mgmt,
					 size_t len,
					 struct ieee80211_rx_status *rx_status,
					 int reassoc)
{
	u8 rates[32];
	size_t rates_len;
	u16 capab_info, status_code, aid;
	struct ieee802_11_elems elems;
	u8 *pos;

	/* AssocResp and ReassocResp have identical structure, so process both
	 * of them in this function. */

	if (wpa_s->mlme.state != IEEE80211_ASSOCIATE) {
		wpa_printf(MSG_DEBUG, "MLME: association frame received from "
			   MACSTR ", but not in associate state - ignored",
			   MAC2STR(mgmt->sa));
		return;
	}

	if (len < 24 + 6) {
		wpa_printf(MSG_DEBUG, "MLME: too short (%lu) association "
			   "frame received from " MACSTR " - ignored",
			   (unsigned long) len, MAC2STR(mgmt->sa));
		return;
	}

	if (os_memcmp(wpa_s->bssid, mgmt->sa, ETH_ALEN) != 0) {
		wpa_printf(MSG_DEBUG, "MLME: association frame received from "
			   "unknown AP (SA=" MACSTR " BSSID=" MACSTR ") - "
			   "ignored", MAC2STR(mgmt->sa), MAC2STR(mgmt->bssid));
		return;
	}

	capab_info = le_to_host16(mgmt->u.assoc_resp.capab_info);
	status_code = le_to_host16(mgmt->u.assoc_resp.status_code);
	aid = le_to_host16(mgmt->u.assoc_resp.aid);
	if ((aid & (BIT(15) | BIT(14))) != (BIT(15) | BIT(14)))
		wpa_printf(MSG_DEBUG, "MLME: invalid aid value %d; bits 15:14 "
			   "not set", aid);
	aid &= ~(BIT(15) | BIT(14));

	wpa_printf(MSG_DEBUG, "MLME: RX %sssocResp from " MACSTR
		   " (capab=0x%x status=%d aid=%d)",
		   reassoc ? "Rea" : "A", MAC2STR(mgmt->sa),
		   capab_info, status_code, aid);

	if (status_code != WLAN_STATUS_SUCCESS) {
		wpa_printf(MSG_DEBUG, "MLME: AP denied association (code=%d)",
			   status_code);
		return;
	}

	pos = mgmt->u.assoc_resp.variable;
	if (ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems)
	    == ParseFailed) {
		wpa_printf(MSG_DEBUG, "MLME: failed to parse AssocResp");
		return;
	}

	if (elems.supp_rates == NULL) {
		wpa_printf(MSG_DEBUG, "MLME: no SuppRates element in "
			   "AssocResp");
		return;
	}

	wpa_printf(MSG_DEBUG, "MLME: associated");
	wpa_s->mlme.aid = aid;
	wpa_s->mlme.ap_capab = capab_info;

	os_free(wpa_s->mlme.assocresp_ies);
	wpa_s->mlme.assocresp_ies_len = len - (pos - (u8 *) mgmt);
	wpa_s->mlme.assocresp_ies = os_malloc(wpa_s->mlme.assocresp_ies_len);
	if (wpa_s->mlme.assocresp_ies) {
		os_memcpy(wpa_s->mlme.assocresp_ies, pos,
			  wpa_s->mlme.assocresp_ies_len);
	}

	ieee80211_set_associated(wpa_s, 1);

	rates_len = elems.supp_rates_len;
	if (rates_len > sizeof(rates))
		rates_len = sizeof(rates);
	os_memcpy(rates, elems.supp_rates, rates_len);
	if (elems.ext_supp_rates) {
		size_t _len = elems.ext_supp_rates_len;
		if (_len > sizeof(rates) - rates_len)
			_len = sizeof(rates) - rates_len;
		os_memcpy(rates + rates_len, elems.ext_supp_rates, _len);
		rates_len += _len;
	}

	if (wpa_drv_set_bssid(wpa_s, wpa_s->bssid) < 0) {
		wpa_printf(MSG_DEBUG, "MLME: failed to set BSSID for the "
			   "netstack");
	}
	if (wpa_drv_set_ssid(wpa_s, wpa_s->mlme.ssid, wpa_s->mlme.ssid_len) <
	    0) {
		wpa_printf(MSG_DEBUG, "MLME: failed to set SSID for the "
			   "netstack");
	}

	/* Remove STA entry before adding a new one just in case to avoid
	 * problems with existing configuration (e.g., keys). */
	wpa_drv_mlme_remove_sta(wpa_s, wpa_s->bssid);
	if (wpa_drv_mlme_add_sta(wpa_s, wpa_s->bssid, rates, rates_len) < 0) {
		wpa_printf(MSG_DEBUG, "MLME: failed to add STA entry to the "
			   "netstack");
	}

#if 0 /* FIX? */
	sta->assoc_ap = 1;

	if (elems.wmm_param && wpa_s->mlme.wmm_enabled) {
		sta->flags |= WLAN_STA_WME;
		ieee80211_sta_wmm_params(wpa_s, elems.wmm_param,
					 elems.wmm_param_len);
	}
#endif

	ieee80211_associated(wpa_s);
}


/* Caller must hold local->sta_bss_lock */
static void __ieee80211_bss_hash_add(struct wpa_supplicant *wpa_s,
				     struct ieee80211_sta_bss *bss)
{
	bss->hnext = wpa_s->mlme.sta_bss_hash[STA_HASH(bss->bssid)];
	wpa_s->mlme.sta_bss_hash[STA_HASH(bss->bssid)] = bss;
}


/* Caller must hold local->sta_bss_lock */
static void __ieee80211_bss_hash_del(struct wpa_supplicant *wpa_s,
				     struct ieee80211_sta_bss *bss)
{
	struct ieee80211_sta_bss *b, *prev = NULL;
	b = wpa_s->mlme.sta_bss_hash[STA_HASH(bss->bssid)];
	while (b) {
		if (b == bss) {
			if (prev == NULL) {
				wpa_s->mlme.sta_bss_hash[STA_HASH(bss->bssid)]
					= bss->hnext;
			} else {
				prev->hnext = bss->hnext;
			}
			break;
		}
		prev = b;
		b = b->hnext;
	}
}


static struct ieee80211_sta_bss *
ieee80211_bss_add(struct wpa_supplicant *wpa_s, const u8 *bssid)
{
	struct ieee80211_sta_bss *bss;

	bss = os_zalloc(sizeof(*bss));
	if (bss == NULL)
		return NULL;
	os_memcpy(bss->bssid, bssid, ETH_ALEN);

	/* TODO: order by RSSI? */
	bss->next = wpa_s->mlme.sta_bss_list;
	wpa_s->mlme.sta_bss_list = bss;
	__ieee80211_bss_hash_add(wpa_s, bss);
	return bss;
}


static struct ieee80211_sta_bss *
ieee80211_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid)
{
	struct ieee80211_sta_bss *bss;

	bss = wpa_s->mlme.sta_bss_hash[STA_HASH(bssid)];
	while (bss) {
		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
			break;
		bss = bss->hnext;
	}
	return bss;
}


static void ieee80211_bss_free(struct wpa_supplicant *wpa_s,
			       struct ieee80211_sta_bss *bss)
{
	__ieee80211_bss_hash_del(wpa_s, bss);
	os_free(bss->wpa_ie);
	os_free(bss->rsn_ie);
	os_free(bss->wmm_ie);
	os_free(bss);
}


static void ieee80211_bss_list_deinit(struct wpa_supplicant *wpa_s)
{
	struct ieee80211_sta_bss *bss, *prev;

	bss = wpa_s->mlme.sta_bss_list;
	wpa_s->mlme.sta_bss_list = NULL;
	while (bss) {
		prev = bss;
		bss = bss->next;
		ieee80211_bss_free(wpa_s, prev);
	}
}