[thirdparty/hostap.git] / src / eap_peer / eap_sake.c

/*
 * EAP peer method: EAP-SAKE (RFC 4763)
 * Copyright (c) 2006-2008, Jouni Malinen <j@w1.fi>
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#include "includes.h"

#include "common.h"
#include "crypto/random.h"
#include "eap_peer/eap_i.h"
#include "eap_common/eap_sake_common.h"

struct eap_sake_data {
	enum { IDENTITY, CHALLENGE, CONFIRM, SUCCESS, FAILURE } state;
	u8 root_secret_a[EAP_SAKE_ROOT_SECRET_LEN];
	u8 root_secret_b[EAP_SAKE_ROOT_SECRET_LEN];
	u8 rand_s[EAP_SAKE_RAND_LEN];
	u8 rand_p[EAP_SAKE_RAND_LEN];
	struct {
		u8 auth[EAP_SAKE_TEK_AUTH_LEN];
		u8 cipher[EAP_SAKE_TEK_CIPHER_LEN];
	} tek;
	u8 msk[EAP_MSK_LEN];
	u8 emsk[EAP_EMSK_LEN];
	u8 session_id;
	int session_id_set;
	u8 *peerid;
	size_t peerid_len;
	u8 *serverid;
	size_t serverid_len;
};


static const char * eap_sake_state_txt(int state)
{
	switch (state) {
	case IDENTITY:
		return "IDENTITY";
	case CHALLENGE:
		return "CHALLENGE";
	case CONFIRM:
		return "CONFIRM";
	case SUCCESS:
		return "SUCCESS";
	case FAILURE:
		return "FAILURE";
	default:
		return "?";
	}
}


static void eap_sake_state(struct eap_sake_data *data, int state)
{
	wpa_printf(MSG_DEBUG, "EAP-SAKE: %s -> %s",
		   eap_sake_state_txt(data->state),
		   eap_sake_state_txt(state));
	data->state = state;
}


static void eap_sake_deinit(struct eap_sm *sm, void *priv);


static void * eap_sake_init(struct eap_sm *sm)
{
	struct eap_sake_data *data;
	const u8 *identity, *password;
	size_t identity_len, password_len;

	password = eap_get_config_password(sm, &password_len);
	if (!password || password_len != 2 * EAP_SAKE_ROOT_SECRET_LEN) {
		wpa_printf(MSG_INFO, "EAP-SAKE: No key of correct length "
			   "configured");
		return NULL;
	}

	data = os_zalloc(sizeof(*data));
	if (data == NULL)
		return NULL;
	data->state = IDENTITY;

	identity = eap_get_config_identity(sm, &identity_len);
	if (identity) {
		data->peerid = os_malloc(identity_len);
		if (data->peerid == NULL) {
			eap_sake_deinit(sm, data);
			return NULL;
		}
		os_memcpy(data->peerid, identity, identity_len);
		data->peerid_len = identity_len;
	}

	os_memcpy(data->root_secret_a, password, EAP_SAKE_ROOT_SECRET_LEN);
	os_memcpy(data->root_secret_b,
		  password + EAP_SAKE_ROOT_SECRET_LEN,
		  EAP_SAKE_ROOT_SECRET_LEN);

	return data;
}


static void eap_sake_deinit(struct eap_sm *sm, void *priv)
{
	struct eap_sake_data *data = priv;
	os_free(data->serverid);
	os_free(data->peerid);
	os_free(data);
}


static struct wpabuf * eap_sake_build_msg(struct eap_sake_data *data,
					  int id, size_t length, u8 subtype)
{
	struct eap_sake_hdr *sake;
	struct wpabuf *msg;
	size_t plen;

	plen = length + sizeof(struct eap_sake_hdr);

	msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_SAKE, plen,
			    EAP_CODE_RESPONSE, id);
	if (msg == NULL) {
		wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to allocate memory "
			   "request");
		return NULL;
	}

	sake = wpabuf_put(msg, sizeof(*sake));
	sake->version = EAP_SAKE_VERSION;
	sake->session_id = data->session_id;
	sake->subtype = subtype;

	return msg;
}


static struct wpabuf * eap_sake_process_identity(struct eap_sm *sm,
						 struct eap_sake_data *data,
						 struct eap_method_ret *ret,
						 const struct wpabuf *reqData,
						 const u8 *payload,
						 size_t payload_len)
{
	struct eap_sake_parse_attr attr;
	struct wpabuf *resp;

	if (data->state != IDENTITY) {
		ret->ignore = TRUE;
		return NULL;
	}

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Request/Identity");

	if (eap_sake_parse_attributes(payload, payload_len, &attr))
		return NULL;

	if (!attr.perm_id_req && !attr.any_id_req) {
		wpa_printf(MSG_INFO, "EAP-SAKE: No AT_PERM_ID_REQ or "
			   "AT_ANY_ID_REQ in Request/Identity");
		return NULL;
	}

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Sending Response/Identity");

	resp = eap_sake_build_msg(data, eap_get_id(reqData),
				  2 + data->peerid_len,
				  EAP_SAKE_SUBTYPE_IDENTITY);
	if (resp == NULL)
		return NULL;

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PEERID");
	eap_sake_add_attr(resp, EAP_SAKE_AT_PEERID,
			  data->peerid, data->peerid_len);

	eap_sake_state(data, CHALLENGE);

	return resp;
}


static struct wpabuf * eap_sake_process_challenge(struct eap_sm *sm,
						  struct eap_sake_data *data,
						  struct eap_method_ret *ret,
						  const struct wpabuf *reqData,
						  const u8 *payload,
						  size_t payload_len)
{
	struct eap_sake_parse_attr attr;
	struct wpabuf *resp;
	u8 *rpos;
	size_t rlen;

	if (data->state != IDENTITY && data->state != CHALLENGE) {
		wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Challenge received "
			   "in unexpected state (%d)", data->state);
		ret->ignore = TRUE;
		return NULL;
	}
	if (data->state == IDENTITY)
		eap_sake_state(data, CHALLENGE);

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Request/Challenge");

	if (eap_sake_parse_attributes(payload, payload_len, &attr))
		return NULL;

	if (!attr.rand_s) {
		wpa_printf(MSG_INFO, "EAP-SAKE: Request/Challenge did not "
			   "include AT_RAND_S");
		return NULL;
	}

	os_memcpy(data->rand_s, attr.rand_s, EAP_SAKE_RAND_LEN);
	wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_S (server rand)",
		    data->rand_s, EAP_SAKE_RAND_LEN);

	if (random_get_bytes(data->rand_p, EAP_SAKE_RAND_LEN)) {
		wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
		return NULL;
	}
	wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_P (peer rand)",
		    data->rand_p, EAP_SAKE_RAND_LEN);

	os_free(data->serverid);
	data->serverid = NULL;
	data->serverid_len = 0;
	if (attr.serverid) {
		wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-SAKE: SERVERID",
				  attr.serverid, attr.serverid_len);
		data->serverid = os_malloc(attr.serverid_len);
		if (data->serverid == NULL)
			return NULL;
		os_memcpy(data->serverid, attr.serverid, attr.serverid_len);
		data->serverid_len = attr.serverid_len;
	}

	eap_sake_derive_keys(data->root_secret_a, data->root_secret_b,
			     data->rand_s, data->rand_p,
			     (u8 *) &data->tek, data->msk, data->emsk);

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Sending Response/Challenge");

	rlen = 2 + EAP_SAKE_RAND_LEN + 2 + EAP_SAKE_MIC_LEN;
	if (data->peerid)
		rlen += 2 + data->peerid_len;
	resp = eap_sake_build_msg(data, eap_get_id(reqData), rlen,
				  EAP_SAKE_SUBTYPE_CHALLENGE);
	if (resp == NULL)
		return NULL;

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_RAND_P");
	eap_sake_add_attr(resp, EAP_SAKE_AT_RAND_P,
			  data->rand_p, EAP_SAKE_RAND_LEN);

	if (data->peerid) {
		wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PEERID");
		eap_sake_add_attr(resp, EAP_SAKE_AT_PEERID,
				  data->peerid, data->peerid_len);
	}

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_P");
	wpabuf_put_u8(resp, EAP_SAKE_AT_MIC_P);
	wpabuf_put_u8(resp, 2 + EAP_SAKE_MIC_LEN);
	rpos = wpabuf_put(resp, EAP_SAKE_MIC_LEN);
	if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
				 data->serverid, data->serverid_len,
				 data->peerid, data->peerid_len, 1,
				 wpabuf_head(resp), wpabuf_len(resp), rpos,
				 rpos)) {
		wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
		wpabuf_free(resp);
		return NULL;
	}

	eap_sake_state(data, CONFIRM);

	return resp;
}


static struct wpabuf * eap_sake_process_confirm(struct eap_sm *sm,
						struct eap_sake_data *data,
						struct eap_method_ret *ret,
						const struct wpabuf *reqData,
						const u8 *payload,
						size_t payload_len)
{
	struct eap_sake_parse_attr attr;
	u8 mic_s[EAP_SAKE_MIC_LEN];
	struct wpabuf *resp;
	u8 *rpos;

	if (data->state != CONFIRM) {
		ret->ignore = TRUE;
		return NULL;
	}

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Request/Confirm");

	if (eap_sake_parse_attributes(payload, payload_len, &attr))
		return NULL;

	if (!attr.mic_s) {
		wpa_printf(MSG_INFO, "EAP-SAKE: Request/Confirm did not "
			   "include AT_MIC_S");
		return NULL;
	}

	eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
			     data->serverid, data->serverid_len,
			     data->peerid, data->peerid_len, 0,
			     wpabuf_head(reqData), wpabuf_len(reqData),
			     attr.mic_s, mic_s);
	if (os_memcmp(attr.mic_s, mic_s, EAP_SAKE_MIC_LEN) != 0) {
		wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_S");
		eap_sake_state(data, FAILURE);
		ret->methodState = METHOD_DONE;
		ret->decision = DECISION_FAIL;
		ret->allowNotifications = FALSE;
		wpa_printf(MSG_DEBUG, "EAP-SAKE: Sending "
			   "Response/Auth-Reject");
		return eap_sake_build_msg(data, eap_get_id(reqData), 0,
					  EAP_SAKE_SUBTYPE_AUTH_REJECT);
	}

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Sending Response/Confirm");

	resp = eap_sake_build_msg(data, eap_get_id(reqData),
				  2 + EAP_SAKE_MIC_LEN,
				  EAP_SAKE_SUBTYPE_CONFIRM);
	if (resp == NULL)
		return NULL;

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_P");
	wpabuf_put_u8(resp, EAP_SAKE_AT_MIC_P);
	wpabuf_put_u8(resp, 2 + EAP_SAKE_MIC_LEN);
	rpos = wpabuf_put(resp, EAP_SAKE_MIC_LEN);
	if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
				 data->serverid, data->serverid_len,
				 data->peerid, data->peerid_len, 1,
				 wpabuf_head(resp), wpabuf_len(resp), rpos,
				 rpos)) {
		wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
		wpabuf_free(resp);
		return NULL;
	}

	eap_sake_state(data, SUCCESS);
	ret->methodState = METHOD_DONE;
	ret->decision = DECISION_UNCOND_SUCC;
	ret->allowNotifications = FALSE;

	return resp;
}


static struct wpabuf * eap_sake_process(struct eap_sm *sm, void *priv,
					struct eap_method_ret *ret,
					const struct wpabuf *reqData)
{
	struct eap_sake_data *data = priv;
	const struct eap_sake_hdr *req;
	struct wpabuf *resp;
	const u8 *pos, *end;
	size_t len;
	u8 subtype, session_id;

	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SAKE, reqData, &len);
	if (pos == NULL || len < sizeof(struct eap_sake_hdr)) {
		ret->ignore = TRUE;
		return NULL;
	}

	req = (const struct eap_sake_hdr *) pos;
	end = pos + len;
	subtype = req->subtype;
	session_id = req->session_id;
	pos = (const u8 *) (req + 1);

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received frame: subtype %d "
		   "session_id %d", subtype, session_id);
	wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Received attributes",
		    pos, end - pos);

	if (data->session_id_set && data->session_id != session_id) {
		wpa_printf(MSG_INFO, "EAP-SAKE: Session ID mismatch (%d,%d)",
			   session_id, data->session_id);
		ret->ignore = TRUE;
		return NULL;
	}
	data->session_id = session_id;
	data->session_id_set = 1;

	ret->ignore = FALSE;
	ret->methodState = METHOD_MAY_CONT;
	ret->decision = DECISION_FAIL;
	ret->allowNotifications = TRUE;

	switch (subtype) {
	case EAP_SAKE_SUBTYPE_IDENTITY:
		resp = eap_sake_process_identity(sm, data, ret, reqData,
						 pos, end - pos);
		break;
	case EAP_SAKE_SUBTYPE_CHALLENGE:
		resp = eap_sake_process_challenge(sm, data, ret, reqData,
						  pos, end - pos);
		break;
	case EAP_SAKE_SUBTYPE_CONFIRM:
		resp = eap_sake_process_confirm(sm, data, ret, reqData,
						pos, end - pos);
		break;
	default:
		wpa_printf(MSG_DEBUG, "EAP-SAKE: Ignoring message with "
			   "unknown subtype %d", subtype);
		ret->ignore = TRUE;
		return NULL;
	}

	if (ret->methodState == METHOD_DONE)
		ret->allowNotifications = FALSE;

	return resp;
}


static Boolean eap_sake_isKeyAvailable(struct eap_sm *sm, void *priv)
{
	struct eap_sake_data *data = priv;
	return data->state == SUCCESS;
}


static u8 * eap_sake_getKey(struct eap_sm *sm, void *priv, size_t *len)
{
	struct eap_sake_data *data = priv;
	u8 *key;

	if (data->state != SUCCESS)
		return NULL;

	key = os_malloc(EAP_MSK_LEN);
	if (key == NULL)
		return NULL;
	os_memcpy(key, data->msk, EAP_MSK_LEN);
	*len = EAP_MSK_LEN;

	return key;
}


static u8 * eap_sake_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
{
	struct eap_sake_data *data = priv;
	u8 *id;

	if (data->state != SUCCESS)
		return NULL;

	*len = 1 + 2 * EAP_SAKE_RAND_LEN;
	id = os_malloc(*len);
	if (id == NULL)
		return NULL;

	id[0] = EAP_TYPE_SAKE;
	os_memcpy(id + 1, data->rand_s, EAP_SAKE_RAND_LEN);
	os_memcpy(id + 1 + EAP_SAKE_RAND_LEN, data->rand_s, EAP_SAKE_RAND_LEN);
	wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Derived Session-Id", id, *len);

	return id;
}


static u8 * eap_sake_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
{
	struct eap_sake_data *data = priv;
	u8 *key;

	if (data->state != SUCCESS)
		return NULL;

	key = os_malloc(EAP_EMSK_LEN);
	if (key == NULL)
		return NULL;
	os_memcpy(key, data->emsk, EAP_EMSK_LEN);
	*len = EAP_EMSK_LEN;

	return key;
}


int eap_peer_sake_register(void)
{
	struct eap_method *eap;
	int ret;

	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
				    EAP_VENDOR_IETF, EAP_TYPE_SAKE, "SAKE");
	if (eap == NULL)
		return -1;

	eap->init = eap_sake_init;
	eap->deinit = eap_sake_deinit;
	eap->process = eap_sake_process;
	eap->isKeyAvailable = eap_sake_isKeyAvailable;
	eap->getKey = eap_sake_getKey;
	eap->getSessionId = eap_sake_get_session_id;
	eap->get_emsk = eap_sake_get_emsk;

	ret = eap_peer_method_register(eap);
	if (ret)
		eap_peer_method_free(eap);
	return ret;
}
Commit	Line	Data
6fc6879b JM	1	/*
	2	* EAP peer method: EAP-SAKE (RFC 4763)
	3	* Copyright (c) 2006-2008, Jouni Malinen <j@w1.fi>
	4	*
0f3d578e JM	5	* This software may be distributed under the terms of the BSD license.
0f3d578e JM	6	* See README for more details.
6fc6879b JM	7	*/
	8
	9	#include "includes.h"
	10
	11	#include "common.h"
3642c431	12	#include "crypto/random.h"
6fc6879b JM	13	#include "eap_peer/eap_i.h"
	14	#include "eap_common/eap_sake_common.h"
	15
	16	struct eap_sake_data {
	17	enum { IDENTITY, CHALLENGE, CONFIRM, SUCCESS, FAILURE } state;
	18	u8 root_secret_a[EAP_SAKE_ROOT_SECRET_LEN];
	19	u8 root_secret_b[EAP_SAKE_ROOT_SECRET_LEN];
	20	u8 rand_s[EAP_SAKE_RAND_LEN];
	21	u8 rand_p[EAP_SAKE_RAND_LEN];
	22	struct {
	23	u8 auth[EAP_SAKE_TEK_AUTH_LEN];
	24	u8 cipher[EAP_SAKE_TEK_CIPHER_LEN];
	25	} tek;
	26	u8 msk[EAP_MSK_LEN];
	27	u8 emsk[EAP_EMSK_LEN];
	28	u8 session_id;
	29	int session_id_set;
	30	u8 *peerid;
	31	size_t peerid_len;
	32	u8 *serverid;
	33	size_t serverid_len;
	34	};
	35
	36
	37	static const char * eap_sake_state_txt(int state)
	38	{
	39	switch (state) {
	40	case IDENTITY:
	41	return "IDENTITY";
	42	case CHALLENGE:
	43	return "CHALLENGE";
	44	case CONFIRM:
	45	return "CONFIRM";
	46	case SUCCESS:
	47	return "SUCCESS";
	48	case FAILURE:
	49	return "FAILURE";
	50	default:
	51	return "?";
	52	}
	53	}
	54
	55
	56	static void eap_sake_state(struct eap_sake_data *data, int state)
	57	{
	58	wpa_printf(MSG_DEBUG, "EAP-SAKE: %s -> %s",
	59	eap_sake_state_txt(data->state),
	60	eap_sake_state_txt(state));
	61	data->state = state;
	62	}
	63
	64
	65	static void eap_sake_deinit(struct eap_sm sm, void priv);
	66
	67
	68	static void * eap_sake_init(struct eap_sm *sm)
	69	{
	70	struct eap_sake_data *data;
	71	const u8 identity, password;
	72	size_t identity_len, password_len;
	73
	74	password = eap_get_config_password(sm, &password_len);
	75	if (!password \|\| password_len != 2 * EAP_SAKE_ROOT_SECRET_LEN) {
	76	wpa_printf(MSG_INFO, "EAP-SAKE: No key of correct length "
77	"configured");
78	return NULL;
79	}
80
81	data = os_zalloc(sizeof(*data));
82	if (data == NULL)
83	return NULL;
84	data->state = IDENTITY;
85
86	identity = eap_get_config_identity(sm, &identity_len);
87	if (identity) {
88	data->peerid = os_malloc(identity_len);
89	if (data->peerid == NULL) {
90	eap_sake_deinit(sm, data);
91	return NULL;
92	}
93	os_memcpy(data->peerid, identity, identity_len);
94	data->peerid_len = identity_len;
95	}
96
97	os_memcpy(data->root_secret_a, password, EAP_SAKE_ROOT_SECRET_LEN);
98	os_memcpy(data->root_secret_b,
99	password + EAP_SAKE_ROOT_SECRET_LEN,
100	EAP_SAKE_ROOT_SECRET_LEN);
101
102	return data;
103	}
104
105
106	static void eap_sake_deinit(struct eap_sm sm, void priv)
107	{
108	struct eap_sake_data *data = priv;
109	os_free(data->serverid);
110	os_free(data->peerid);
111	os_free(data);
112	}
113
114
115	static struct wpabuf * eap_sake_build_msg(struct eap_sake_data *data,
116	int id, size_t length, u8 subtype)
117	{
118	struct eap_sake_hdr *sake;
119	struct wpabuf *msg;
120	size_t plen;
121
122	plen = length + sizeof(struct eap_sake_hdr);
123
124	msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_SAKE, plen,
125	EAP_CODE_RESPONSE, id);
126	if (msg == NULL) {
127	wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to allocate memory "
128	"request");
129	return NULL;
130	}
131
132	sake = wpabuf_put(msg, sizeof(*sake));
133	sake->version = EAP_SAKE_VERSION;
134	sake->session_id = data->session_id;
135	sake->subtype = subtype;
136
137	return msg;
138	}
139
140
141	static struct wpabuf * eap_sake_process_identity(struct eap_sm *sm,
142	struct eap_sake_data *data,
143	struct eap_method_ret *ret,
144	const struct wpabuf *reqData,
145	const u8 *payload,
146	size_t payload_len)
147	{
148	struct eap_sake_parse_attr attr;
149	struct wpabuf *resp;
150
151	if (data->state != IDENTITY) {
152	ret->ignore = TRUE;
153	return NULL;
154	}
155
156	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Request/Identity");
157
158	if (eap_sake_parse_attributes(payload, payload_len, &attr))
159	return NULL;
160
161	if (!attr.perm_id_req && !attr.any_id_req) {
162	wpa_printf(MSG_INFO, "EAP-SAKE: No AT_PERM_ID_REQ or "
163	"AT_ANY_ID_REQ in Request/Identity");
164	return NULL;
165	}
166
167	wpa_printf(MSG_DEBUG, "EAP-SAKE: Sending Response/Identity");
168
169	resp = eap_sake_build_msg(data, eap_get_id(reqData),
170	2 + data->peerid_len,
171	EAP_SAKE_SUBTYPE_IDENTITY);
172	if (resp == NULL)
173	return NULL;
174
175	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PEERID");
176	eap_sake_add_attr(resp, EAP_SAKE_AT_PEERID,
177	data->peerid, data->peerid_len);
178
179	eap_sake_state(data, CHALLENGE);
180
181	return resp;
182	}
183
184
185	static struct wpabuf * eap_sake_process_challenge(struct eap_sm *sm,
186	struct eap_sake_data *data,
187	struct eap_method_ret *ret,
188	const struct wpabuf *reqData,
189	const u8 *payload,
190	size_t payload_len)
191	{
192	struct eap_sake_parse_attr attr;
193	struct wpabuf *resp;
194	u8 *rpos;
195	size_t rlen;
196
197	if (data->state != IDENTITY && data->state != CHALLENGE) {
198	wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Challenge received "
199	"in unexpected state (%d)", data->state);
200	ret->ignore = TRUE;
201	return NULL;
202	}
203	if (data->state == IDENTITY)
204	eap_sake_state(data, CHALLENGE);
205
206	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Request/Challenge");
207
208	if (eap_sake_parse_attributes(payload, payload_len, &attr))
209	return NULL;
210
211	if (!attr.rand_s) {
212	wpa_printf(MSG_INFO, "EAP-SAKE: Request/Challenge did not "
213	"include AT_RAND_S");
214	return NULL;
215	}
216
217	os_memcpy(data->rand_s, attr.rand_s, EAP_SAKE_RAND_LEN);
218	wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_S (server rand)",
219	data->rand_s, EAP_SAKE_RAND_LEN);
220
3642c431	221	if (random_get_bytes(data->rand_p, EAP_SAKE_RAND_LEN)) {
6fc6879b JM	222	wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
	223	return NULL;
	224	}
	225	wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_P (peer rand)",
	226	data->rand_p, EAP_SAKE_RAND_LEN);
	227
	228	os_free(data->serverid);
	229	data->serverid = NULL;
	230	data->serverid_len = 0;
	231	if (attr.serverid) {
	232	wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-SAKE: SERVERID",
	233	attr.serverid, attr.serverid_len);
	234	data->serverid = os_malloc(attr.serverid_len);
	235	if (data->serverid == NULL)
	236	return NULL;
	237	os_memcpy(data->serverid, attr.serverid, attr.serverid_len);
	238	data->serverid_len = attr.serverid_len;
	239	}
	240
	241	eap_sake_derive_keys(data->root_secret_a, data->root_secret_b,
	242	data->rand_s, data->rand_p,
	243	(u8 *) &data->tek, data->msk, data->emsk);
	244
	245	wpa_printf(MSG_DEBUG, "EAP-SAKE: Sending Response/Challenge");
	246
	247	rlen = 2 + EAP_SAKE_RAND_LEN + 2 + EAP_SAKE_MIC_LEN;
	248	if (data->peerid)
	249	rlen += 2 + data->peerid_len;
	250	resp = eap_sake_build_msg(data, eap_get_id(reqData), rlen,
	251	EAP_SAKE_SUBTYPE_CHALLENGE);
	252	if (resp == NULL)
	253	return NULL;
	254
	255	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_RAND_P");
	256	eap_sake_add_attr(resp, EAP_SAKE_AT_RAND_P,
	257	data->rand_p, EAP_SAKE_RAND_LEN);
	258
	259	if (data->peerid) {
	260	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PEERID");
	261	eap_sake_add_attr(resp, EAP_SAKE_AT_PEERID,
	262	data->peerid, data->peerid_len);
	263	}
	264
	265	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_P");
	266	wpabuf_put_u8(resp, EAP_SAKE_AT_MIC_P);
	267	wpabuf_put_u8(resp, 2 + EAP_SAKE_MIC_LEN);
	268	rpos = wpabuf_put(resp, EAP_SAKE_MIC_LEN);
	269	if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
	270	data->serverid, data->serverid_len,
	271	data->peerid, data->peerid_len, 1,
	272	wpabuf_head(resp), wpabuf_len(resp), rpos,
	273	rpos)) {
	274	wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
	275	wpabuf_free(resp);
	276	return NULL;
	277	}
	278
	279	eap_sake_state(data, CONFIRM);
	280
	281	return resp;
	282	}
	283
	284
	285	static struct wpabuf * eap_sake_process_confirm(struct eap_sm *sm,
286	struct eap_sake_data *data,
287	struct eap_method_ret *ret,
288	const struct wpabuf *reqData,
289	const u8 *payload,
290	size_t payload_len)
291	{
292	struct eap_sake_parse_attr attr;
293	u8 mic_s[EAP_SAKE_MIC_LEN];
294	struct wpabuf *resp;
295	u8 *rpos;
296
297	if (data->state != CONFIRM) {
298	ret->ignore = TRUE;
299	return NULL;
300	}
301
302	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Request/Confirm");
303
304	if (eap_sake_parse_attributes(payload, payload_len, &attr))
305	return NULL;
306
307	if (!attr.mic_s) {
308	wpa_printf(MSG_INFO, "EAP-SAKE: Request/Confirm did not "
309	"include AT_MIC_S");
310	return NULL;
311	}
312
313	eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
314	data->serverid, data->serverid_len,
315	data->peerid, data->peerid_len, 0,
316	wpabuf_head(reqData), wpabuf_len(reqData),
317	attr.mic_s, mic_s);
318	if (os_memcmp(attr.mic_s, mic_s, EAP_SAKE_MIC_LEN) != 0) {
319	wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_S");
320	eap_sake_state(data, FAILURE);
321	ret->methodState = METHOD_DONE;
322	ret->decision = DECISION_FAIL;
323	ret->allowNotifications = FALSE;
324	wpa_printf(MSG_DEBUG, "EAP-SAKE: Sending "
325	"Response/Auth-Reject");
326	return eap_sake_build_msg(data, eap_get_id(reqData), 0,
327	EAP_SAKE_SUBTYPE_AUTH_REJECT);
328	}
329
330	wpa_printf(MSG_DEBUG, "EAP-SAKE: Sending Response/Confirm");
331
332	resp = eap_sake_build_msg(data, eap_get_id(reqData),
333	2 + EAP_SAKE_MIC_LEN,
334	EAP_SAKE_SUBTYPE_CONFIRM);
335	if (resp == NULL)
336	return NULL;
337
338	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_P");
339	wpabuf_put_u8(resp, EAP_SAKE_AT_MIC_P);
340	wpabuf_put_u8(resp, 2 + EAP_SAKE_MIC_LEN);
341	rpos = wpabuf_put(resp, EAP_SAKE_MIC_LEN);
342	if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
343	data->serverid, data->serverid_len,
344	data->peerid, data->peerid_len, 1,
345	wpabuf_head(resp), wpabuf_len(resp), rpos,
346	rpos)) {
347	wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
348	wpabuf_free(resp);
349	return NULL;
350	}
351
352	eap_sake_state(data, SUCCESS);
353	ret->methodState = METHOD_DONE;
354	ret->decision = DECISION_UNCOND_SUCC;
355	ret->allowNotifications = FALSE;
356
357	return resp;
358	}
359
360
361	static struct wpabuf * eap_sake_process(struct eap_sm sm, void priv,
362	struct eap_method_ret *ret,
363	const struct wpabuf *reqData)
364	{
365	struct eap_sake_data *data = priv;
366	const struct eap_sake_hdr *req;
367	struct wpabuf *resp;
368	const u8 pos, end;
369	size_t len;
370	u8 subtype, session_id;
371
372	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SAKE, reqData, &len);
373	if (pos == NULL \|\| len < sizeof(struct eap_sake_hdr)) {
374	ret->ignore = TRUE;
375	return NULL;
376	}
377
378	req = (const struct eap_sake_hdr *) pos;
379	end = pos + len;
380	subtype = req->subtype;
381	session_id = req->session_id;
382	pos = (const u8 *) (req + 1);
383
384	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received frame: subtype %d "
385	"session_id %d", subtype, session_id);
386	wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Received attributes",
387	pos, end - pos);
388
389	if (data->session_id_set && data->session_id != session_id) {
390	wpa_printf(MSG_INFO, "EAP-SAKE: Session ID mismatch (%d,%d)",
391	session_id, data->session_id);
392	ret->ignore = TRUE;
393	return NULL;
394	}
395	data->session_id = session_id;
396	data->session_id_set = 1;
397
398	ret->ignore = FALSE;
399	ret->methodState = METHOD_MAY_CONT;
400	ret->decision = DECISION_FAIL;
401	ret->allowNotifications = TRUE;
402
403	switch (subtype) {
404	case EAP_SAKE_SUBTYPE_IDENTITY:
405	resp = eap_sake_process_identity(sm, data, ret, reqData,
406	pos, end - pos);
407	break;
408	case EAP_SAKE_SUBTYPE_CHALLENGE:
409	resp = eap_sake_process_challenge(sm, data, ret, reqData,
410	pos, end - pos);
411	break;
412	case EAP_SAKE_SUBTYPE_CONFIRM:
413	resp = eap_sake_process_confirm(sm, data, ret, reqData,
414	pos, end - pos);
415	break;
416	default:
417	wpa_printf(MSG_DEBUG, "EAP-SAKE: Ignoring message with "
418	"unknown subtype %d", subtype);
419	ret->ignore = TRUE;
420	return NULL;
421	}
422
423	if (ret->methodState == METHOD_DONE)
424	ret->allowNotifications = FALSE;
425
426	return resp;
427	}
428
429
430	static Boolean eap_sake_isKeyAvailable(struct eap_sm sm, void priv)
431	{
432	struct eap_sake_data *data = priv;
433	return data->state == SUCCESS;
434	}
435
436
437	static u8 * eap_sake_getKey(struct eap_sm sm, void priv, size_t *len)
438	{
439	struct eap_sake_data *data = priv;
440	u8 *key;
441
442	if (data->state != SUCCESS)
443	return NULL;
444
445	key = os_malloc(EAP_MSK_LEN);
446	if (key == NULL)
447	return NULL;
448	os_memcpy(key, data->msk, EAP_MSK_LEN);
449	*len = EAP_MSK_LEN;
450
451	return key;
452	}
453
454
9ca84274 JM	455	static u8 * eap_sake_get_session_id(struct eap_sm sm, void priv, size_t *len)
	456	{
	457	struct eap_sake_data *data = priv;
	458	u8 *id;
	459
	460	if (data->state != SUCCESS)
	461	return NULL;
	462
	463	len = 1 + 2 EAP_SAKE_RAND_LEN;
	464	id = os_malloc(*len);
	465	if (id == NULL)
	466	return NULL;
	467
	468	id[0] = EAP_TYPE_SAKE;
	469	os_memcpy(id + 1, data->rand_s, EAP_SAKE_RAND_LEN);
	470	os_memcpy(id + 1 + EAP_SAKE_RAND_LEN, data->rand_s, EAP_SAKE_RAND_LEN);
	471	wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Derived Session-Id", id, *len);
	472
	473	return id;
	474	}
	475
	476
6fc6879b JM	477	static u8 * eap_sake_get_emsk(struct eap_sm sm, void priv, size_t *len)
	478	{
	479	struct eap_sake_data *data = priv;
	480	u8 *key;
	481
	482	if (data->state != SUCCESS)
	483	return NULL;
	484
	485	key = os_malloc(EAP_EMSK_LEN);
	486	if (key == NULL)
	487	return NULL;
	488	os_memcpy(key, data->emsk, EAP_EMSK_LEN);
	489	*len = EAP_EMSK_LEN;
	490
	491	return key;
	492	}
	493
	494
	495	int eap_peer_sake_register(void)
	496	{
	497	struct eap_method *eap;
	498	int ret;
	499
	500	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
	501	EAP_VENDOR_IETF, EAP_TYPE_SAKE, "SAKE");
	502	if (eap == NULL)
	503	return -1;
	504
	505	eap->init = eap_sake_init;
	506	eap->deinit = eap_sake_deinit;
	507	eap->process = eap_sake_process;
	508	eap->isKeyAvailable = eap_sake_isKeyAvailable;
	509	eap->getKey = eap_sake_getKey;
9ca84274	510	eap->getSessionId = eap_sake_get_session_id;
6fc6879b JM	511	eap->get_emsk = eap_sake_get_emsk;
	512
	513	ret = eap_peer_method_register(eap);
	514	if (ret)
	515	eap_peer_method_free(eap);
	516	return ret;
	517	}