[thirdparty/hostap.git] / src / common / gas.c

/*
 * Generic advertisement service (GAS) (IEEE 802.11u)
 * Copyright (c) 2009, Atheros Communications
 * Copyright (c) 2011-2012, Qualcomm Atheros
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#include "includes.h"

#include "common.h"
#include "ieee802_11_defs.h"
#include "gas.h"


static struct wpabuf *
gas_build_req(u8 action, u8 dialog_token, size_t size)
{
	struct wpabuf *buf;

	buf = wpabuf_alloc(100 + size);
	if (buf == NULL)
		return NULL;

	wpabuf_put_u8(buf, WLAN_ACTION_PUBLIC);
	wpabuf_put_u8(buf, action);
	wpabuf_put_u8(buf, dialog_token);

	return buf;
}


struct wpabuf * gas_build_initial_req(u8 dialog_token, size_t size)
{
	return gas_build_req(WLAN_PA_GAS_INITIAL_REQ, dialog_token,
			     size);
}


struct wpabuf * gas_build_comeback_req(u8 dialog_token)
{
	return gas_build_req(WLAN_PA_GAS_COMEBACK_REQ, dialog_token, 0);
}


static struct wpabuf *
gas_build_resp(u8 action, u8 dialog_token, u16 status_code, u8 frag_id,
	       u8 more, u16 comeback_delay, size_t size)
{
	struct wpabuf *buf;

	buf = wpabuf_alloc(100 + size);
	if (buf == NULL)
		return NULL;

	wpabuf_put_u8(buf, WLAN_ACTION_PUBLIC);
	wpabuf_put_u8(buf, action);
	wpabuf_put_u8(buf, dialog_token);
	wpabuf_put_le16(buf, status_code);
	if (action == WLAN_PA_GAS_COMEBACK_RESP)
		wpabuf_put_u8(buf, frag_id | (more ? 0x80 : 0));
	wpabuf_put_le16(buf, comeback_delay);

	return buf;
}


struct wpabuf *
gas_build_initial_resp(u8 dialog_token, u16 status_code, u16 comeback_delay,
		       size_t size)
{
	return gas_build_resp(WLAN_PA_GAS_INITIAL_RESP, dialog_token,
			      status_code, 0, 0, comeback_delay, size);
}


struct wpabuf *
gas_build_comeback_resp(u8 dialog_token, u16 status_code, u8 frag_id, u8 more,
			u16 comeback_delay, size_t size)
{
	return gas_build_resp(WLAN_PA_GAS_COMEBACK_RESP, dialog_token,
			      status_code, frag_id, more, comeback_delay,
			      size);
}


/**
 * gas_add_adv_proto_anqp - Add an Advertisement Protocol element
 * @buf: Buffer to which the element is added
 * @query_resp_len_limit: Query Response Length Limit in units of 256 octets
 * @pame_bi: Pre-Association Message Exchange BSSID Independent (0/1)
 *
 *
 * @query_resp_len_limit is 0 for request and 1-0x7f for response. 0x7f means
 * that the maximum limit is determined by the maximum allowable number of
 * fragments in the GAS Query Response Fragment ID.
 */
static void gas_add_adv_proto_anqp(struct wpabuf *buf, u8 query_resp_len_limit,
				   u8 pame_bi)
{
	/* Advertisement Protocol IE */
	wpabuf_put_u8(buf, WLAN_EID_ADV_PROTO);
	wpabuf_put_u8(buf, 2); /* Length */
	wpabuf_put_u8(buf, (query_resp_len_limit & 0x7f) |
		      (pame_bi ? 0x80 : 0));
	/* Advertisement Protocol */
	wpabuf_put_u8(buf, ACCESS_NETWORK_QUERY_PROTOCOL);
}


struct wpabuf * gas_anqp_build_initial_req(u8 dialog_token, size_t size)
{
	struct wpabuf *buf;

	buf = gas_build_initial_req(dialog_token, 4 + size);
	if (buf == NULL)
		return NULL;

	gas_add_adv_proto_anqp(buf, 0, 0);

	wpabuf_put(buf, 2); /* Query Request Length to be filled */

	return buf;
}


struct wpabuf * gas_anqp_build_initial_resp(u8 dialog_token, u16 status_code,
					    u16 comeback_delay, size_t size)
{
	struct wpabuf *buf;

	buf = gas_build_initial_resp(dialog_token, status_code, comeback_delay,
				     4 + size);
	if (buf == NULL)
		return NULL;

	gas_add_adv_proto_anqp(buf, 0x7f, 0);

	wpabuf_put(buf, 2); /* Query Response Length to be filled */

	return buf;
}


struct wpabuf * gas_anqp_build_initial_resp_buf(u8 dialog_token,
						u16 status_code,
						u16 comeback_delay,
						struct wpabuf *payload)
{
	struct wpabuf *buf;

	buf = gas_anqp_build_initial_resp(dialog_token, status_code,
					  comeback_delay,
					  payload ? wpabuf_len(payload) : 0);
	if (buf == NULL)
		return NULL;

	if (payload)
		wpabuf_put_buf(buf, payload);

	gas_anqp_set_len(buf);

	return buf;
}


struct wpabuf * gas_anqp_build_comeback_resp(u8 dialog_token, u16 status_code,
					     u8 frag_id, u8 more,
					     u16 comeback_delay, size_t size)
{
	struct wpabuf *buf;

	buf = gas_build_comeback_resp(dialog_token, status_code,
				      frag_id, more, comeback_delay, 4 + size);
	if (buf == NULL)
		return NULL;

	gas_add_adv_proto_anqp(buf, 0x7f, 0);

	wpabuf_put(buf, 2); /* Query Response Length to be filled */

	return buf;
}


struct wpabuf * gas_anqp_build_comeback_resp_buf(u8 dialog_token,
						 u16 status_code,
						 u8 frag_id, u8 more,
						 u16 comeback_delay,
						 struct wpabuf *payload)
{
	struct wpabuf *buf;

	buf = gas_anqp_build_comeback_resp(dialog_token, status_code, frag_id,
					   more, comeback_delay,
					   payload ? wpabuf_len(payload) : 0);
	if (buf == NULL)
		return NULL;

	if (payload)
		wpabuf_put_buf(buf, payload);

	gas_anqp_set_len(buf);

	return buf;
}


/**
 * gas_anqp_set_len - Set Query Request/Response Length
 * @buf: GAS message
 *
 * This function is used to update the Query Request/Response Length field once
 * the payload has been filled.
 */
void gas_anqp_set_len(struct wpabuf *buf)
{
	u8 action;
	size_t offset;
	u8 *len;

	if (buf == NULL || wpabuf_len(buf) < 2)
		return;

	action = *(wpabuf_head_u8(buf) + 1);
	switch (action) {
	case WLAN_PA_GAS_INITIAL_REQ:
		offset = 3 + 4;
		break;
	case WLAN_PA_GAS_INITIAL_RESP:
		offset = 7 + 4;
		break;
	case WLAN_PA_GAS_COMEBACK_RESP:
		offset = 8 + 4;
		break;
	default:
		return;
	}

	if (wpabuf_len(buf) < offset + 2)
		return;

	len = wpabuf_mhead_u8(buf) + offset;
	WPA_PUT_LE16(len, (u8 *) wpabuf_put(buf, 0) - len - 2);
}


/**
 * gas_anqp_add_element - Add ANQP element header
 * @buf: GAS message
 * @info_id: ANQP Info ID
 * Returns: Pointer to the Length field for gas_anqp_set_element_len()
 */
u8 * gas_anqp_add_element(struct wpabuf *buf, u16 info_id)
{
	wpabuf_put_le16(buf, info_id);
	return wpabuf_put(buf, 2); /* Length to be filled */
}


/**
 * gas_anqp_set_element_len - Update ANQP element Length field
 * @buf: GAS message
 * @len_pos: Length field position from gas_anqp_add_element()
 *
 * This function is called after the ANQP element payload has been added to the
 * buffer.
 */
void gas_anqp_set_element_len(struct wpabuf *buf, u8 *len_pos)
{
	WPA_PUT_LE16(len_pos, (u8 *) wpabuf_put(buf, 0) - len_pos - 2);
}
Commit	Line	Data
0c840c33 JM	1	/*
	2	* Generic advertisement service (GAS) (IEEE 802.11u)
	3	* Copyright (c) 2009, Atheros Communications
b1f12296	4	* Copyright (c) 2011-2012, Qualcomm Atheros
0c840c33	5	*
e22d4d95 JM	6	* This software may be distributed under the terms of the BSD license.
e22d4d95 JM	7	* See README for more details.
0c840c33 JM	8	*/
	9
	10	#include "includes.h"
	11
	12	#include "common.h"
	13	#include "ieee802_11_defs.h"
	14	#include "gas.h"
	15
	16
	17	static struct wpabuf *
	18	gas_build_req(u8 action, u8 dialog_token, size_t size)
	19	{
	20	struct wpabuf *buf;
	21
	22	buf = wpabuf_alloc(100 + size);
	23	if (buf == NULL)
	24	return NULL;
	25
	26	wpabuf_put_u8(buf, WLAN_ACTION_PUBLIC);
	27	wpabuf_put_u8(buf, action);
	28	wpabuf_put_u8(buf, dialog_token);
	29
	30	return buf;
	31	}
	32
	33
b1f12296	34	struct wpabuf * gas_build_initial_req(u8 dialog_token, size_t size)
0c840c33 JM	35	{
	36	return gas_build_req(WLAN_PA_GAS_INITIAL_REQ, dialog_token,
	37	size);
	38	}
	39
	40
	41	struct wpabuf * gas_build_comeback_req(u8 dialog_token)
	42	{
	43	return gas_build_req(WLAN_PA_GAS_COMEBACK_REQ, dialog_token, 0);
	44	}
	45
	46
	47	static struct wpabuf *
	48	gas_build_resp(u8 action, u8 dialog_token, u16 status_code, u8 frag_id,
	49	u8 more, u16 comeback_delay, size_t size)
	50	{
	51	struct wpabuf *buf;
	52
	53	buf = wpabuf_alloc(100 + size);
	54	if (buf == NULL)
	55	return NULL;
	56
	57	wpabuf_put_u8(buf, WLAN_ACTION_PUBLIC);
	58	wpabuf_put_u8(buf, action);
	59	wpabuf_put_u8(buf, dialog_token);
	60	wpabuf_put_le16(buf, status_code);
	61	if (action == WLAN_PA_GAS_COMEBACK_RESP)
	62	wpabuf_put_u8(buf, frag_id \| (more ? 0x80 : 0));
	63	wpabuf_put_le16(buf, comeback_delay);
	64
	65	return buf;
	66	}
	67
	68
69fbdfe4	69	struct wpabuf *
0c840c33 JM	70	gas_build_initial_resp(u8 dialog_token, u16 status_code, u16 comeback_delay,
	71	size_t size)
	72	{
	73	return gas_build_resp(WLAN_PA_GAS_INITIAL_RESP, dialog_token,
	74	status_code, 0, 0, comeback_delay, size);
	75	}
	76
	77
461d39af	78	struct wpabuf *
0c840c33 JM	79	gas_build_comeback_resp(u8 dialog_token, u16 status_code, u8 frag_id, u8 more,
	80	u16 comeback_delay, size_t size)
	81	{
	82	return gas_build_resp(WLAN_PA_GAS_COMEBACK_RESP, dialog_token,
	83	status_code, frag_id, more, comeback_delay,
	84	size);
	85	}
	86
	87
	88	/**
	89	* gas_add_adv_proto_anqp - Add an Advertisement Protocol element
	90	* @buf: Buffer to which the element is added
	91	* @query_resp_len_limit: Query Response Length Limit in units of 256 octets
	92	* @pame_bi: Pre-Association Message Exchange BSSID Independent (0/1)
	93	*
	94	*
	95	* @query_resp_len_limit is 0 for request and 1-0x7f for response. 0x7f means
	96	* that the maximum limit is determined by the maximum allowable number of
	97	* fragments in the GAS Query Response Fragment ID.
	98	*/
	99	static void gas_add_adv_proto_anqp(struct wpabuf *buf, u8 query_resp_len_limit,
	100	u8 pame_bi)
	101	{
	102	/* Advertisement Protocol IE */
	103	wpabuf_put_u8(buf, WLAN_EID_ADV_PROTO);
	104	wpabuf_put_u8(buf, 2); /* Length */
	105	wpabuf_put_u8(buf, (query_resp_len_limit & 0x7f) \|
	106	(pame_bi ? 0x80 : 0));
	107	/* Advertisement Protocol */
	108	wpabuf_put_u8(buf, ACCESS_NETWORK_QUERY_PROTOCOL);
	109	}
	110
	111
	112	struct wpabuf * gas_anqp_build_initial_req(u8 dialog_token, size_t size)
	113	{
	114	struct wpabuf *buf;
	115
	116	buf = gas_build_initial_req(dialog_token, 4 + size);
	117	if (buf == NULL)
	118	return NULL;
	119
	120	gas_add_adv_proto_anqp(buf, 0, 0);
	121
	122	wpabuf_put(buf, 2); /* Query Request Length to be filled */
	123
	124	return buf;
	125	}
	126
	127
	128	struct wpabuf * gas_anqp_build_initial_resp(u8 dialog_token, u16 status_code,
	129	u16 comeback_delay, size_t size)
	130	{
	131	struct wpabuf *buf;
	132
	133	buf = gas_build_initial_resp(dialog_token, status_code, comeback_delay,
	134	4 + size);
	135	if (buf == NULL)
	136	return NULL;
	137
	138	gas_add_adv_proto_anqp(buf, 0x7f, 0);
	139
	140	wpabuf_put(buf, 2); /* Query Response Length to be filled */
	141
	142	return buf;
143	}
144
145
146	struct wpabuf * gas_anqp_build_initial_resp_buf(u8 dialog_token,
147	u16 status_code,
148	u16 comeback_delay,
149	struct wpabuf *payload)
150	{
151	struct wpabuf *buf;
152
153	buf = gas_anqp_build_initial_resp(dialog_token, status_code,
154	comeback_delay,
155	payload ? wpabuf_len(payload) : 0);
156	if (buf == NULL)
157	return NULL;
158
159	if (payload)
160	wpabuf_put_buf(buf, payload);
161
162	gas_anqp_set_len(buf);
163
164	return buf;
165	}
166
167
168	struct wpabuf * gas_anqp_build_comeback_resp(u8 dialog_token, u16 status_code,
169	u8 frag_id, u8 more,
170	u16 comeback_delay, size_t size)
171	{
172	struct wpabuf *buf;
173
174	buf = gas_build_comeback_resp(dialog_token, status_code,
175	frag_id, more, comeback_delay, 4 + size);
176	if (buf == NULL)
177	return NULL;
178
179	gas_add_adv_proto_anqp(buf, 0x7f, 0);
180
181	wpabuf_put(buf, 2); /* Query Response Length to be filled */
182
183	return buf;
184	}
185
186
187	struct wpabuf * gas_anqp_build_comeback_resp_buf(u8 dialog_token,
188	u16 status_code,
189	u8 frag_id, u8 more,
190	u16 comeback_delay,
191	struct wpabuf *payload)
192	{
193	struct wpabuf *buf;
194
195	buf = gas_anqp_build_comeback_resp(dialog_token, status_code, frag_id,
196	more, comeback_delay,
197	payload ? wpabuf_len(payload) : 0);
198	if (buf == NULL)
199	return NULL;
200
201	if (payload)
202	wpabuf_put_buf(buf, payload);
203
204	gas_anqp_set_len(buf);
205
206	return buf;
207	}
208
209
210	/**
211	* gas_anqp_set_len - Set Query Request/Response Length
212	* @buf: GAS message
213	*
214	* This function is used to update the Query Request/Response Length field once
215	* the payload has been filled.
216	*/
217	void gas_anqp_set_len(struct wpabuf *buf)
218	{
219	u8 action;
220	size_t offset;
221	u8 *len;
222
223	if (buf == NULL \|\| wpabuf_len(buf) < 2)
224	return;
225
226	action = *(wpabuf_head_u8(buf) + 1);
227	switch (action) {
228	case WLAN_PA_GAS_INITIAL_REQ:
229	offset = 3 + 4;
230	break;
231	case WLAN_PA_GAS_INITIAL_RESP:
232	offset = 7 + 4;
233	break;
234	case WLAN_PA_GAS_COMEBACK_RESP:
235	offset = 8 + 4;
236	break;
237	default:
238	return;
239	}
240
241	if (wpabuf_len(buf) < offset + 2)
242	return;
243
244	len = wpabuf_mhead_u8(buf) + offset;
245	WPA_PUT_LE16(len, (u8 *) wpabuf_put(buf, 0) - len - 2);
246	}
247
248
249	/**
250	* gas_anqp_add_element - Add ANQP element header
251	* @buf: GAS message
252	* @info_id: ANQP Info ID
253	* Returns: Pointer to the Length field for gas_anqp_set_element_len()
254	*/
255	u8 * gas_anqp_add_element(struct wpabuf *buf, u16 info_id)
256	{
257	wpabuf_put_le16(buf, info_id);
258	return wpabuf_put(buf, 2); /* Length to be filled */
259	}
260
261
262	/**
263	* gas_anqp_set_element_len - Update ANQP element Length field
264	* @buf: GAS message
265	* @len_pos: Length field position from gas_anqp_add_element()
266	*
267	* This function is called after the ANQP element payload has been added to the
268	* buffer.
269	*/
270	void gas_anqp_set_element_len(struct wpabuf buf, u8 len_pos)
271	{
272	WPA_PUT_LE16(len_pos, (u8 *) wpabuf_put(buf, 0) - len_pos - 2);
273	}