src/eap_server/eap_server_sake.c - vendor/opensource/hostap - Git at Google

 /*
  * hostapd / EAP-SAKE (RFC 4763) server
  * Copyright (c) 2006-2007, 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_server/eap_i.h"
 #include "eap_common/eap_sake_common.h"


 struct eap_sake_data {
 	enum { IDENTITY, CHALLENGE, CONFIRM, SUCCESS, FAILURE } state;
 	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;
 	u8 *peerid;
 	size_t peerid_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_init(struct eap_sm *sm)
 {
 	struct eap_sake_data *data;

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

 	if (os_get_random(&data->session_id, 1)) {
 		wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
 		os_free(data);
 		return NULL;
 	}
 	wpa_printf(MSG_DEBUG, "EAP-SAKE: Initialized Session ID %d",
 		   data->session_id);

 	return data;
 }


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


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

 	plen = sizeof(struct eap_sake_hdr) + length;

 	msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_SAKE, plen,
 			    EAP_CODE_REQUEST, 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_build_identity(struct eap_sm *sm,
 					       struct eap_sake_data *data,
 					       u8 id)
 {
 	struct wpabuf *msg;
 	size_t plen;

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

 	plen = 4;
 	plen += 2 + sm->server_id_len;
 	msg = eap_sake_build_msg(data, id, plen, EAP_SAKE_SUBTYPE_IDENTITY);
 	if (msg == NULL) {
 		data->state = FAILURE;
 		return NULL;
 	}

 	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PERM_ID_REQ");
 	eap_sake_add_attr(msg, EAP_SAKE_AT_PERM_ID_REQ, NULL, 2);

 	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
 	eap_sake_add_attr(msg, EAP_SAKE_AT_SERVERID,
 			  sm->server_id, sm->server_id_len);

 	return msg;
 }


 static struct wpabuf * eap_sake_build_challenge(struct eap_sm *sm,
 						struct eap_sake_data *data,
 						u8 id)
 {
 	struct wpabuf *msg;
 	size_t plen;

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

 	if (random_get_bytes(data->rand_s, EAP_SAKE_RAND_LEN)) {
 		wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
 		data->state = FAILURE;
 		return NULL;
 	}
 	wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_S (server rand)",
 		    data->rand_s, EAP_SAKE_RAND_LEN);

 	plen = 2 + EAP_SAKE_RAND_LEN + 2 + sm->server_id_len;
 	msg = eap_sake_build_msg(data, id, plen, EAP_SAKE_SUBTYPE_CHALLENGE);
 	if (msg == NULL) {
 		data->state = FAILURE;
 		return NULL;
 	}

 	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_RAND_S");
 	eap_sake_add_attr(msg, EAP_SAKE_AT_RAND_S,
 			  data->rand_s, EAP_SAKE_RAND_LEN);

 	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
 	eap_sake_add_attr(msg, EAP_SAKE_AT_SERVERID,
 			  sm->server_id, sm->server_id_len);

 	return msg;
 }


 static struct wpabuf * eap_sake_build_confirm(struct eap_sm *sm,
 					      struct eap_sake_data *data,
 					      u8 id)
 {
 	struct wpabuf *msg;
 	u8 *mic;

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

 	msg = eap_sake_build_msg(data, id, 2 + EAP_SAKE_MIC_LEN,
 				 EAP_SAKE_SUBTYPE_CONFIRM);
 	if (msg == NULL) {
 		data->state = FAILURE;
 		return NULL;
 	}

 	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_S");
 	wpabuf_put_u8(msg, EAP_SAKE_AT_MIC_S);
 	wpabuf_put_u8(msg, 2 + EAP_SAKE_MIC_LEN);
 	mic = wpabuf_put(msg, EAP_SAKE_MIC_LEN);
 	if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
 				 sm->server_id, sm->server_id_len,
 				 data->peerid, data->peerid_len, 0,
 				 wpabuf_head(msg), wpabuf_len(msg), mic, mic))
 	{
 		wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
 		data->state = FAILURE;
 		os_free(msg);
 		return NULL;
 	}

 	return msg;
 }


 static struct wpabuf * eap_sake_buildReq(struct eap_sm *sm, void *priv, u8 id)
 {
 	struct eap_sake_data *data = priv;

 	switch (data->state) {
 	case IDENTITY:
 		return eap_sake_build_identity(sm, data, id);
 	case CHALLENGE:
 		return eap_sake_build_challenge(sm, data, id);
 	case CONFIRM:
 		return eap_sake_build_confirm(sm, data, id);
 	default:
 		wpa_printf(MSG_DEBUG, "EAP-SAKE: Unknown state %d in buildReq",
 			   data->state);
 		break;
 	}
 	return NULL;
 }


 static Boolean eap_sake_check(struct eap_sm *sm, void *priv,
 			      struct wpabuf *respData)
 {
 	struct eap_sake_data *data = priv;
 	struct eap_sake_hdr *resp;
 	size_t len;
 	u8 version, session_id, subtype;
 	const u8 *pos;

 	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SAKE, respData, &len);
 	if (pos == NULL || len < sizeof(struct eap_sake_hdr)) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Invalid frame");
 		return TRUE;
 	}

 	resp = (struct eap_sake_hdr *) pos;
 	version = resp->version;
 	session_id = resp->session_id;
 	subtype = resp->subtype;

 	if (version != EAP_SAKE_VERSION) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Unknown version %d", version);
 		return TRUE;
 	}

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

 	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received frame: subtype=%d", subtype);

 	if (data->state == IDENTITY && subtype == EAP_SAKE_SUBTYPE_IDENTITY)
 		return FALSE;

 	if (data->state == CHALLENGE && subtype == EAP_SAKE_SUBTYPE_CHALLENGE)
 		return FALSE;

 	if (data->state == CONFIRM && subtype == EAP_SAKE_SUBTYPE_CONFIRM)
 		return FALSE;

 	if (subtype == EAP_SAKE_SUBTYPE_AUTH_REJECT)
 		return FALSE;

 	wpa_printf(MSG_INFO, "EAP-SAKE: Unexpected subtype=%d in state=%d",
 		   subtype, data->state);

 	return TRUE;
 }


 static void eap_sake_process_identity(struct eap_sm *sm,
 				      struct eap_sake_data *data,
 				      const struct wpabuf *respData,
 				      const u8 *payload, size_t payloadlen)
 {
 	if (data->state != IDENTITY)
 		return;

 	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Identity");
 	/* TODO: update identity and select new user data */
 	eap_sake_state(data, CHALLENGE);
 }


 static void eap_sake_process_challenge(struct eap_sm *sm,
 				       struct eap_sake_data *data,
 				       const struct wpabuf *respData,
 				       const u8 *payload, size_t payloadlen)
 {
 	struct eap_sake_parse_attr attr;
 	u8 mic_p[EAP_SAKE_MIC_LEN];

 	if (data->state != CHALLENGE)
 		return;

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

 	if (eap_sake_parse_attributes(payload, payloadlen, &attr))
 		return;

 	if (!attr.rand_p || !attr.mic_p) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Response/Challenge did not "
 			   "include AT_RAND_P or AT_MIC_P");
 		return;
 	}

 	os_memcpy(data->rand_p, attr.rand_p, EAP_SAKE_RAND_LEN);

 	os_free(data->peerid);
 	data->peerid = NULL;
 	data->peerid_len = 0;
 	if (attr.peerid) {
 		data->peerid = os_malloc(attr.peerid_len);
 		if (data->peerid == NULL)
 			return;
 		os_memcpy(data->peerid, attr.peerid, attr.peerid_len);
 		data->peerid_len = attr.peerid_len;
 	}

 	if (sm->user == NULL || sm->user->password == NULL ||
 	    sm->user->password_len != 2 * EAP_SAKE_ROOT_SECRET_LEN) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Plaintext password with "
 			   "%d-byte key not configured",
 			   2 * EAP_SAKE_ROOT_SECRET_LEN);
 		data->state = FAILURE;
 		return;
 	}
 	eap_sake_derive_keys(sm->user->password,
 			     sm->user->password + EAP_SAKE_ROOT_SECRET_LEN,
 			     data->rand_s, data->rand_p,
 			     (u8 *) &data->tek, data->msk, data->emsk);

 	eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
 			     sm->server_id, sm->server_id_len,
 			     data->peerid, data->peerid_len, 1,
 			     wpabuf_head(respData), wpabuf_len(respData),
 			     attr.mic_p, mic_p);
 	if (os_memcmp_const(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
 		eap_sake_state(data, FAILURE);
 		return;
 	}

 	eap_sake_state(data, CONFIRM);
 }


 static void eap_sake_process_confirm(struct eap_sm *sm,
 				     struct eap_sake_data *data,
 				     const struct wpabuf *respData,
 				     const u8 *payload, size_t payloadlen)
 {
 	struct eap_sake_parse_attr attr;
 	u8 mic_p[EAP_SAKE_MIC_LEN];

 	if (data->state != CONFIRM)
 		return;

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

 	if (eap_sake_parse_attributes(payload, payloadlen, &attr))
 		return;

 	if (!attr.mic_p) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Response/Confirm did not "
 			   "include AT_MIC_P");
 		return;
 	}

 	eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
 			     sm->server_id, sm->server_id_len,
 			     data->peerid, data->peerid_len, 1,
 			     wpabuf_head(respData), wpabuf_len(respData),
 			     attr.mic_p, mic_p);
 	if (os_memcmp_const(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
 		eap_sake_state(data, FAILURE);
 	} else
 		eap_sake_state(data, SUCCESS);
 }


 static void eap_sake_process_auth_reject(struct eap_sm *sm,
 					 struct eap_sake_data *data,
 					 const struct wpabuf *respData,
 					 const u8 *payload, size_t payloadlen)
 {
 	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Auth-Reject");
 	eap_sake_state(data, FAILURE);
 }


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

 	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SAKE, respData, &len);
 	if (pos == NULL || len < sizeof(struct eap_sake_hdr))
 		return;

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

 	wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Received attributes",
 		    pos, end - pos);

 	switch (subtype) {
 	case EAP_SAKE_SUBTYPE_IDENTITY:
 		eap_sake_process_identity(sm, data, respData, pos, end - pos);
 		break;
 	case EAP_SAKE_SUBTYPE_CHALLENGE:
 		eap_sake_process_challenge(sm, data, respData, pos, end - pos);
 		break;
 	case EAP_SAKE_SUBTYPE_CONFIRM:
 		eap_sake_process_confirm(sm, data, respData, pos, end - pos);
 		break;
 	case EAP_SAKE_SUBTYPE_AUTH_REJECT:
 		eap_sake_process_auth_reject(sm, data, respData, pos,
 					     end - pos);
 		break;
 	}
 }


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


 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_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;
 }


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


 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;
 }


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

 	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
 				      EAP_VENDOR_IETF, EAP_TYPE_SAKE, "SAKE");
 	if (eap == NULL)
 		return -1;

 	eap->init = eap_sake_init;
 	eap->reset = eap_sake_reset;
 	eap->buildReq = eap_sake_buildReq;
 	eap->check = eap_sake_check;
 	eap->process = eap_sake_process;
 	eap->isDone = eap_sake_isDone;
 	eap->getKey = eap_sake_getKey;
 	eap->isSuccess = eap_sake_isSuccess;
 	eap->get_emsk = eap_sake_get_emsk;
 	eap->getSessionId = eap_sake_get_session_id;

 	ret = eap_server_method_register(eap);
 	if (ret)
 		eap_server_method_free(eap);
 	return ret;
 }
	/*
	* hostapd / EAP-SAKE (RFC 4763) server
	* Copyright (c) 2006-2007, 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_server/eap_i.h"
	#include "eap_common/eap_sake_common.h"


	struct eap_sake_data {
	enum { IDENTITY, CHALLENGE, CONFIRM, SUCCESS, FAILURE } state;
	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;
	u8 *peerid;
	size_t peerid_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_init(struct eap_sm *sm)
	{
	struct eap_sake_data *data;

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

	if (os_get_random(&data->session_id, 1)) {
	wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
	os_free(data);
	return NULL;
	}
	wpa_printf(MSG_DEBUG, "EAP-SAKE: Initialized Session ID %d",
	data->session_id);

	return data;
	}


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


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

	plen = sizeof(struct eap_sake_hdr) + length;

	msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_SAKE, plen,
	EAP_CODE_REQUEST, 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_build_identity(struct eap_sm *sm,
	struct eap_sake_data *data,
	u8 id)
	{
	struct wpabuf *msg;
	size_t plen;

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

	plen = 4;
	plen += 2 + sm->server_id_len;
	msg = eap_sake_build_msg(data, id, plen, EAP_SAKE_SUBTYPE_IDENTITY);
	if (msg == NULL) {
	data->state = FAILURE;
	return NULL;
	}

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PERM_ID_REQ");
	eap_sake_add_attr(msg, EAP_SAKE_AT_PERM_ID_REQ, NULL, 2);

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
	eap_sake_add_attr(msg, EAP_SAKE_AT_SERVERID,
	sm->server_id, sm->server_id_len);

	return msg;
	}


	static struct wpabuf * eap_sake_build_challenge(struct eap_sm *sm,
	struct eap_sake_data *data,
	u8 id)
	{
	struct wpabuf *msg;
	size_t plen;

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

	if (random_get_bytes(data->rand_s, EAP_SAKE_RAND_LEN)) {
	wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
	data->state = FAILURE;
	return NULL;
	}
	wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_S (server rand)",
	data->rand_s, EAP_SAKE_RAND_LEN);

	plen = 2 + EAP_SAKE_RAND_LEN + 2 + sm->server_id_len;
	msg = eap_sake_build_msg(data, id, plen, EAP_SAKE_SUBTYPE_CHALLENGE);
	if (msg == NULL) {
	data->state = FAILURE;
	return NULL;
	}

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_RAND_S");
	eap_sake_add_attr(msg, EAP_SAKE_AT_RAND_S,
	data->rand_s, EAP_SAKE_RAND_LEN);

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
	eap_sake_add_attr(msg, EAP_SAKE_AT_SERVERID,
	sm->server_id, sm->server_id_len);

	return msg;
	}


	static struct wpabuf * eap_sake_build_confirm(struct eap_sm *sm,
	struct eap_sake_data *data,
	u8 id)
	{
	struct wpabuf *msg;
	u8 *mic;

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

	msg = eap_sake_build_msg(data, id, 2 + EAP_SAKE_MIC_LEN,
	EAP_SAKE_SUBTYPE_CONFIRM);
	if (msg == NULL) {
	data->state = FAILURE;
	return NULL;
	}

	wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_S");
	wpabuf_put_u8(msg, EAP_SAKE_AT_MIC_S);
	wpabuf_put_u8(msg, 2 + EAP_SAKE_MIC_LEN);
	mic = wpabuf_put(msg, EAP_SAKE_MIC_LEN);
	if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
	sm->server_id, sm->server_id_len,
	data->peerid, data->peerid_len, 0,
	wpabuf_head(msg), wpabuf_len(msg), mic, mic))
	{
	wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
	data->state = FAILURE;
	os_free(msg);
	return NULL;
	}

	return msg;
	}


	static struct wpabuf * eap_sake_buildReq(struct eap_sm sm, void priv, u8 id)
	{
	struct eap_sake_data *data = priv;

	switch (data->state) {
	case IDENTITY:
	return eap_sake_build_identity(sm, data, id);
	case CHALLENGE:
	return eap_sake_build_challenge(sm, data, id);
	case CONFIRM:
	return eap_sake_build_confirm(sm, data, id);
	default:
	wpa_printf(MSG_DEBUG, "EAP-SAKE: Unknown state %d in buildReq",
	data->state);
	break;
	}
	return NULL;
	}


	static Boolean eap_sake_check(struct eap_sm sm, void priv,
	struct wpabuf *respData)
	{
	struct eap_sake_data *data = priv;
	struct eap_sake_hdr *resp;
	size_t len;
	u8 version, session_id, subtype;
	const u8 *pos;

	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SAKE, respData, &len);
	if (pos == NULL \|\| len < sizeof(struct eap_sake_hdr)) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Invalid frame");
	return TRUE;
	}

	resp = (struct eap_sake_hdr *) pos;
	version = resp->version;
	session_id = resp->session_id;
	subtype = resp->subtype;

	if (version != EAP_SAKE_VERSION) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Unknown version %d", version);
	return TRUE;
	}

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

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received frame: subtype=%d", subtype);

	if (data->state == IDENTITY && subtype == EAP_SAKE_SUBTYPE_IDENTITY)
	return FALSE;

	if (data->state == CHALLENGE && subtype == EAP_SAKE_SUBTYPE_CHALLENGE)
	return FALSE;

	if (data->state == CONFIRM && subtype == EAP_SAKE_SUBTYPE_CONFIRM)
	return FALSE;

	if (subtype == EAP_SAKE_SUBTYPE_AUTH_REJECT)
	return FALSE;

	wpa_printf(MSG_INFO, "EAP-SAKE: Unexpected subtype=%d in state=%d",
	subtype, data->state);

	return TRUE;
	}


	static void eap_sake_process_identity(struct eap_sm *sm,
	struct eap_sake_data *data,
	const struct wpabuf *respData,
	const u8 *payload, size_t payloadlen)
	{
	if (data->state != IDENTITY)
	return;

	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Identity");
	/* TODO: update identity and select new user data */
	eap_sake_state(data, CHALLENGE);
	}


	static void eap_sake_process_challenge(struct eap_sm *sm,
	struct eap_sake_data *data,
	const struct wpabuf *respData,
	const u8 *payload, size_t payloadlen)
	{
	struct eap_sake_parse_attr attr;
	u8 mic_p[EAP_SAKE_MIC_LEN];

	if (data->state != CHALLENGE)
	return;

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

	if (eap_sake_parse_attributes(payload, payloadlen, &attr))
	return;

	if (!attr.rand_p \|\| !attr.mic_p) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Response/Challenge did not "
	"include AT_RAND_P or AT_MIC_P");
	return;
	}

	os_memcpy(data->rand_p, attr.rand_p, EAP_SAKE_RAND_LEN);

	os_free(data->peerid);
	data->peerid = NULL;
	data->peerid_len = 0;
	if (attr.peerid) {
	data->peerid = os_malloc(attr.peerid_len);
	if (data->peerid == NULL)
	return;
	os_memcpy(data->peerid, attr.peerid, attr.peerid_len);
	data->peerid_len = attr.peerid_len;
	}

	if (sm->user == NULL \|\| sm->user->password == NULL \|\|
	sm->user->password_len != 2 * EAP_SAKE_ROOT_SECRET_LEN) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Plaintext password with "
	"%d-byte key not configured",
	2 * EAP_SAKE_ROOT_SECRET_LEN);
	data->state = FAILURE;
	return;
	}
	eap_sake_derive_keys(sm->user->password,
	sm->user->password + EAP_SAKE_ROOT_SECRET_LEN,
	data->rand_s, data->rand_p,
	(u8 *) &data->tek, data->msk, data->emsk);

	eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
	sm->server_id, sm->server_id_len,
	data->peerid, data->peerid_len, 1,
	wpabuf_head(respData), wpabuf_len(respData),
	attr.mic_p, mic_p);
	if (os_memcmp_const(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
	eap_sake_state(data, FAILURE);
	return;
	}

	eap_sake_state(data, CONFIRM);
	}


	static void eap_sake_process_confirm(struct eap_sm *sm,
	struct eap_sake_data *data,
	const struct wpabuf *respData,
	const u8 *payload, size_t payloadlen)
	{
	struct eap_sake_parse_attr attr;
	u8 mic_p[EAP_SAKE_MIC_LEN];

	if (data->state != CONFIRM)
	return;

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

	if (eap_sake_parse_attributes(payload, payloadlen, &attr))
	return;

	if (!attr.mic_p) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Response/Confirm did not "
	"include AT_MIC_P");
	return;
	}

	eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
	sm->server_id, sm->server_id_len,
	data->peerid, data->peerid_len, 1,
	wpabuf_head(respData), wpabuf_len(respData),
	attr.mic_p, mic_p);
	if (os_memcmp_const(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
	wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
	eap_sake_state(data, FAILURE);
	} else
	eap_sake_state(data, SUCCESS);
	}


	static void eap_sake_process_auth_reject(struct eap_sm *sm,
	struct eap_sake_data *data,
	const struct wpabuf *respData,
	const u8 *payload, size_t payloadlen)
	{
	wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Auth-Reject");
	eap_sake_state(data, FAILURE);
	}


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

	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SAKE, respData, &len);
	if (pos == NULL \|\| len < sizeof(struct eap_sake_hdr))
	return;

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

	wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Received attributes",
	pos, end - pos);

	switch (subtype) {
	case EAP_SAKE_SUBTYPE_IDENTITY:
	eap_sake_process_identity(sm, data, respData, pos, end - pos);
	break;
	case EAP_SAKE_SUBTYPE_CHALLENGE:
	eap_sake_process_challenge(sm, data, respData, pos, end - pos);
	break;
	case EAP_SAKE_SUBTYPE_CONFIRM:
	eap_sake_process_confirm(sm, data, respData, pos, end - pos);
	break;
	case EAP_SAKE_SUBTYPE_AUTH_REJECT:
	eap_sake_process_auth_reject(sm, data, respData, pos,
	end - pos);
	break;
	}
	}


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


	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_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;
	}


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


	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;
	}


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

	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
	EAP_VENDOR_IETF, EAP_TYPE_SAKE, "SAKE");
	if (eap == NULL)
	return -1;

	eap->init = eap_sake_init;
	eap->reset = eap_sake_reset;
	eap->buildReq = eap_sake_buildReq;
	eap->check = eap_sake_check;
	eap->process = eap_sake_process;
	eap->isDone = eap_sake_isDone;
	eap->getKey = eap_sake_getKey;
	eap->isSuccess = eap_sake_isSuccess;
	eap->get_emsk = eap_sake_get_emsk;
	eap->getSessionId = eap_sake_get_session_id;

	ret = eap_server_method_register(eap);
	if (ret)
	eap_server_method_free(eap);
	return ret;
	}