src/eap_peer/eap_sake.c - LeafOS-Project/android_external_wpa_supplicant_8 - Gitiles

 /*
  * EAP peer method: EAP-SAKE (RFC 4763)
  * Copyright (c) 2006-2019, 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_memdup(identity, identity_len);
 		if (data->peerid == NULL) {
 			eap_sake_deinit(sm, data);
 			return NULL;
 		}
 		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);
 	bin_clear_free(data, sizeof(*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,
 						 u8 id,
 						 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, id, 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,
 						  u8 id,
 						  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_memdup(attr.serverid, attr.serverid_len);
 		if (data->serverid == NULL)
 			return NULL;
 		data->serverid_len = attr.serverid_len;
 	}

 	if (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) < 0) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Failed to derive keys");
 		return NULL;
 	}

 	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, id, 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,
 						u8 id,
 						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;
 	}

 	if (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)) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
 		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, id, 0,
 					  EAP_SAKE_SUBTYPE_AUTH_REJECT);
 	}
 	if (os_memcmp_const(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, id, 0,
 					  EAP_SAKE_SUBTYPE_AUTH_REJECT);
 	}

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

 	resp = eap_sake_build_msg(data, id, 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, 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;
 	id = eap_get_id(reqData);
 	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, id,
 						 pos, end - pos);
 		break;
 	case EAP_SAKE_SUBTYPE_CHALLENGE:
 		resp = eap_sake_process_challenge(sm, data, ret, id,
 						  pos, end - pos);
 		break;
 	case EAP_SAKE_SUBTYPE_CONFIRM:
 		resp = eap_sake_process_confirm(sm, data, ret, id, 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 bool 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_memdup(data->msk, EAP_MSK_LEN);
 	if (key == NULL)
 		return NULL;
 	*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_memdup(data->emsk, EAP_EMSK_LEN);
 	if (key == NULL)
 		return NULL;
 	*len = EAP_EMSK_LEN;

 	return key;
 }


 int eap_peer_sake_register(void)
 {
 	struct eap_method *eap;

 	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;

 	return eap_peer_method_register(eap);
 }
	/*
	* EAP peer method: EAP-SAKE (RFC 4763)
	* Copyright (c) 2006-2019, 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_memdup(identity, identity_len);
	if (data->peerid == NULL) {
	eap_sake_deinit(sm, data);
	return NULL;
	}
	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);
	bin_clear_free(data, sizeof(*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,
	u8 id,
	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, id, 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,
	u8 id,
	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_memdup(attr.serverid, attr.serverid_len);
	if (data->serverid == NULL)
	return NULL;
	data->serverid_len = attr.serverid_len;
	}

	if (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) < 0) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Failed to derive keys");
	return NULL;
	}

	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, id, 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,
	u8 id,
	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;
	}

	if (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)) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
	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, id, 0,
	EAP_SAKE_SUBTYPE_AUTH_REJECT);
	}
	if (os_memcmp_const(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, id, 0,
	EAP_SAKE_SUBTYPE_AUTH_REJECT);
	}

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

	resp = eap_sake_build_msg(data, id, 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, 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;
	id = eap_get_id(reqData);
	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, id,
	pos, end - pos);
	break;
	case EAP_SAKE_SUBTYPE_CHALLENGE:
	resp = eap_sake_process_challenge(sm, data, ret, id,
	pos, end - pos);
	break;
	case EAP_SAKE_SUBTYPE_CONFIRM:
	resp = eap_sake_process_confirm(sm, data, ret, id, 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 bool 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_memdup(data->msk, EAP_MSK_LEN);
	if (key == NULL)
	return NULL;
	*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_memdup(data->emsk, EAP_EMSK_LEN);
	if (key == NULL)
	return NULL;
	*len = EAP_EMSK_LEN;

	return key;
	}


	int eap_peer_sake_register(void)
	{
	struct eap_method *eap;

	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;

	return eap_peer_method_register(eap);
	}