1/*
2 * hostapd - WNM
3 * Copyright (c) 2011-2012, Qualcomm Atheros, Inc.
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "utils/includes.h"
10
11#include "utils/common.h"
12#include "common/ieee802_11_defs.h"
13#include "ap/hostapd.h"
14#include "ap/sta_info.h"
15#include "ap/ap_config.h"
16#include "ap/ap_drv_ops.h"
17#include "ap/wpa_auth.h"
18#include "wnm_ap.h"
19
20#define MAX_TFS_IE_LEN  1024
21
22
23/* get the TFS IE from driver */
24static int ieee80211_11_get_tfs_ie(struct hostapd_data *hapd, const u8 *addr,
25				   u8 *buf, u16 *buf_len, enum wnm_oper oper)
26{
27	wpa_printf(MSG_DEBUG, "%s: TFS get operation %d", __func__, oper);
28
29	return hostapd_drv_wnm_oper(hapd, oper, addr, buf, buf_len);
30}
31
32
33/* set the TFS IE to driver */
34static int ieee80211_11_set_tfs_ie(struct hostapd_data *hapd, const u8 *addr,
35				   u8 *buf, u16 *buf_len, enum wnm_oper oper)
36{
37	wpa_printf(MSG_DEBUG, "%s: TFS set operation %d", __func__, oper);
38
39	return hostapd_drv_wnm_oper(hapd, oper, addr, buf, buf_len);
40}
41
42
43/* MLME-SLEEPMODE.response */
44static int ieee802_11_send_wnmsleep_resp(struct hostapd_data *hapd,
45					 const u8 *addr, u8 dialog_token,
46					 u8 action_type, u16 intval)
47{
48	struct ieee80211_mgmt *mgmt;
49	int res;
50	size_t len;
51	size_t gtk_elem_len = 0;
52	size_t igtk_elem_len = 0;
53	struct wnm_sleep_element wnmsleep_ie;
54	u8 *wnmtfs_ie;
55	u8 wnmsleep_ie_len;
56	u16 wnmtfs_ie_len;
57	u8 *pos;
58	struct sta_info *sta;
59	enum wnm_oper tfs_oper = action_type == WNM_SLEEP_MODE_ENTER ?
60		WNM_SLEEP_TFS_RESP_IE_ADD : WNM_SLEEP_TFS_RESP_IE_NONE;
61
62	sta = ap_get_sta(hapd, addr);
63	if (sta == NULL) {
64		wpa_printf(MSG_DEBUG, "%s: station not found", __func__);
65		return -EINVAL;
66	}
67
68	/* WNM-Sleep Mode IE */
69	os_memset(&wnmsleep_ie, 0, sizeof(struct wnm_sleep_element));
70	wnmsleep_ie_len = sizeof(struct wnm_sleep_element);
71	wnmsleep_ie.eid = WLAN_EID_WNMSLEEP;
72	wnmsleep_ie.len = wnmsleep_ie_len - 2;
73	wnmsleep_ie.action_type = action_type;
74	wnmsleep_ie.status = WNM_STATUS_SLEEP_ACCEPT;
75	wnmsleep_ie.intval = intval;
76
77	/* TFS IE(s) */
78	wnmtfs_ie = os_zalloc(MAX_TFS_IE_LEN);
79	if (wnmtfs_ie == NULL)
80		return -1;
81	if (ieee80211_11_get_tfs_ie(hapd, addr, wnmtfs_ie, &wnmtfs_ie_len,
82				    tfs_oper)) {
83		wnmtfs_ie_len = 0;
84		os_free(wnmtfs_ie);
85		wnmtfs_ie = NULL;
86	}
87
88#define MAX_GTK_SUBELEM_LEN 45
89#define MAX_IGTK_SUBELEM_LEN 26
90	mgmt = os_zalloc(sizeof(*mgmt) + wnmsleep_ie_len +
91			 MAX_GTK_SUBELEM_LEN + MAX_IGTK_SUBELEM_LEN);
92	if (mgmt == NULL) {
93		wpa_printf(MSG_DEBUG, "MLME: Failed to allocate buffer for "
94			   "WNM-Sleep Response action frame");
95		return -1;
96	}
97	os_memcpy(mgmt->da, addr, ETH_ALEN);
98	os_memcpy(mgmt->sa, hapd->own_addr, ETH_ALEN);
99	os_memcpy(mgmt->bssid, hapd->own_addr, ETH_ALEN);
100	mgmt->frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
101					   WLAN_FC_STYPE_ACTION);
102	mgmt->u.action.category = WLAN_ACTION_WNM;
103	mgmt->u.action.u.wnm_sleep_resp.action = WNM_SLEEP_MODE_RESP;
104	mgmt->u.action.u.wnm_sleep_resp.dialogtoken = dialog_token;
105	pos = (u8 *)mgmt->u.action.u.wnm_sleep_resp.variable;
106	/* add key data if MFP is enabled */
107	if (!wpa_auth_uses_mfp(sta->wpa_sm) ||
108	    action_type != WNM_SLEEP_MODE_EXIT) {
109		mgmt->u.action.u.wnm_sleep_resp.keydata_len = 0;
110	} else {
111		gtk_elem_len = wpa_wnmsleep_gtk_subelem(sta->wpa_sm, pos);
112		pos += gtk_elem_len;
113		wpa_printf(MSG_DEBUG, "Pass 4, gtk_len = %d",
114			   (int) gtk_elem_len);
115#ifdef CONFIG_IEEE80211W
116		res = wpa_wnmsleep_igtk_subelem(sta->wpa_sm, pos);
117		if (res < 0) {
118			os_free(wnmtfs_ie);
119			os_free(mgmt);
120			return -1;
121		}
122		igtk_elem_len = res;
123		pos += igtk_elem_len;
124		wpa_printf(MSG_DEBUG, "Pass 4 igtk_len = %d",
125			   (int) igtk_elem_len);
126#endif /* CONFIG_IEEE80211W */
127
128		WPA_PUT_LE16((u8 *)
129			     &mgmt->u.action.u.wnm_sleep_resp.keydata_len,
130			     gtk_elem_len + igtk_elem_len);
131	}
132	os_memcpy(pos, &wnmsleep_ie, wnmsleep_ie_len);
133	/* copy TFS IE here */
134	pos += wnmsleep_ie_len;
135	if (wnmtfs_ie)
136		os_memcpy(pos, wnmtfs_ie, wnmtfs_ie_len);
137
138	len = 1 + sizeof(mgmt->u.action.u.wnm_sleep_resp) + gtk_elem_len +
139		igtk_elem_len + wnmsleep_ie_len + wnmtfs_ie_len;
140
141	/* In driver, response frame should be forced to sent when STA is in
142	 * PS mode */
143	res = hostapd_drv_send_action(hapd, hapd->iface->freq, 0,
144				      mgmt->da, &mgmt->u.action.category, len);
145
146	if (!res) {
147		wpa_printf(MSG_DEBUG, "Successfully send WNM-Sleep Response "
148			   "frame");
149
150		/* when entering wnmsleep
151		 * 1. pause the node in driver
152		 * 2. mark the node so that AP won't update GTK/IGTK during
153		 * WNM Sleep
154		 */
155		if (wnmsleep_ie.status == WNM_STATUS_SLEEP_ACCEPT &&
156		    wnmsleep_ie.action_type == WNM_SLEEP_MODE_ENTER) {
157			hostapd_drv_wnm_oper(hapd, WNM_SLEEP_ENTER_CONFIRM,
158					     addr, NULL, NULL);
159			wpa_set_wnmsleep(sta->wpa_sm, 1);
160		}
161		/* when exiting wnmsleep
162		 * 1. unmark the node
163		 * 2. start GTK/IGTK update if MFP is not used
164		 * 3. unpause the node in driver
165		 */
166		if ((wnmsleep_ie.status == WNM_STATUS_SLEEP_ACCEPT ||
167		     wnmsleep_ie.status ==
168		     WNM_STATUS_SLEEP_EXIT_ACCEPT_GTK_UPDATE) &&
169		    wnmsleep_ie.action_type == WNM_SLEEP_MODE_EXIT) {
170			wpa_set_wnmsleep(sta->wpa_sm, 0);
171			hostapd_drv_wnm_oper(hapd, WNM_SLEEP_EXIT_CONFIRM,
172					     addr, NULL, NULL);
173			if (!wpa_auth_uses_mfp(sta->wpa_sm))
174				wpa_wnmsleep_rekey_gtk(sta->wpa_sm);
175		}
176	} else
177		wpa_printf(MSG_DEBUG, "Fail to send WNM-Sleep Response frame");
178
179#undef MAX_GTK_SUBELEM_LEN
180#undef MAX_IGTK_SUBELEM_LEN
181	os_free(wnmtfs_ie);
182	os_free(mgmt);
183	return res;
184}
185
186
187static void ieee802_11_rx_wnmsleep_req(struct hostapd_data *hapd,
188				       const u8 *addr, const u8 *frm, int len)
189{
190	/* Dialog Token [1] | WNM-Sleep Mode IE | TFS Response IE */
191	const u8 *pos = frm;
192	u8 dialog_token;
193	struct wnm_sleep_element *wnmsleep_ie = NULL;
194	/* multiple TFS Req IE (assuming consecutive) */
195	u8 *tfsreq_ie_start = NULL;
196	u8 *tfsreq_ie_end = NULL;
197	u16 tfsreq_ie_len = 0;
198
199	dialog_token = *pos++;
200	while (pos + 1 < frm + len) {
201		u8 ie_len = pos[1];
202		if (pos + 2 + ie_len > frm + len)
203			break;
204		if (*pos == WLAN_EID_WNMSLEEP)
205			wnmsleep_ie = (struct wnm_sleep_element *) pos;
206		else if (*pos == WLAN_EID_TFS_REQ) {
207			if (!tfsreq_ie_start)
208				tfsreq_ie_start = (u8 *) pos;
209			tfsreq_ie_end = (u8 *) pos;
210		} else
211			wpa_printf(MSG_DEBUG, "WNM: EID %d not recognized",
212				   *pos);
213		pos += ie_len + 2;
214	}
215
216	if (!wnmsleep_ie) {
217		wpa_printf(MSG_DEBUG, "No WNM-Sleep IE found");
218		return;
219	}
220
221	if (wnmsleep_ie->action_type == WNM_SLEEP_MODE_ENTER &&
222	    tfsreq_ie_start && tfsreq_ie_end &&
223	    tfsreq_ie_end - tfsreq_ie_start >= 0) {
224		tfsreq_ie_len = (tfsreq_ie_end + tfsreq_ie_end[1] + 2) -
225			tfsreq_ie_start;
226		wpa_printf(MSG_DEBUG, "TFS Req IE(s) found");
227		/* pass the TFS Req IE(s) to driver for processing */
228		if (ieee80211_11_set_tfs_ie(hapd, addr, tfsreq_ie_start,
229					    &tfsreq_ie_len,
230					    WNM_SLEEP_TFS_REQ_IE_SET))
231			wpa_printf(MSG_DEBUG, "Fail to set TFS Req IE");
232	}
233
234	ieee802_11_send_wnmsleep_resp(hapd, addr, dialog_token,
235				      wnmsleep_ie->action_type,
236				      wnmsleep_ie->intval);
237
238	if (wnmsleep_ie->action_type == WNM_SLEEP_MODE_EXIT) {
239		/* clear the tfs after sending the resp frame */
240		ieee80211_11_set_tfs_ie(hapd, addr, tfsreq_ie_start,
241					&tfsreq_ie_len, WNM_SLEEP_TFS_IE_DEL);
242	}
243}
244
245
246int ieee802_11_rx_wnm_action_ap(struct hostapd_data *hapd,
247				struct rx_action *action)
248{
249	if (action->len < 1 || action->data == NULL)
250		return -1;
251
252	switch (action->data[0]) {
253	case WNM_BSS_TRANS_MGMT_QUERY:
254		wpa_printf(MSG_DEBUG, "WNM: BSS Transition Management Query");
255		/* TODO */
256		return -1;
257	case WNM_BSS_TRANS_MGMT_RESP:
258		wpa_printf(MSG_DEBUG, "WNM: BSS Transition Management "
259			   "Response");
260		/* TODO */
261		return -1;
262	case WNM_SLEEP_MODE_REQ:
263		ieee802_11_rx_wnmsleep_req(hapd, action->sa, action->data + 1,
264					   action->len - 1);
265		return 0;
266	}
267
268	wpa_printf(MSG_DEBUG, "WNM: Unsupported WNM Action %u from " MACSTR,
269		   action->data[0], MAC2STR(action->sa));
270	return -1;
271}
272