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

 /*
  * hostapd / EAP-GPSK (RFC 5433) 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_gpsk_common.h"


 struct eap_gpsk_data {
 	enum { GPSK_1, GPSK_3, SUCCESS, FAILURE } state;
 	u8 rand_server[EAP_GPSK_RAND_LEN];
 	u8 rand_peer[EAP_GPSK_RAND_LEN];
 	u8 msk[EAP_MSK_LEN];
 	u8 emsk[EAP_EMSK_LEN];
 	u8 sk[EAP_GPSK_MAX_SK_LEN];
 	size_t sk_len;
 	u8 pk[EAP_GPSK_MAX_PK_LEN];
 	size_t pk_len;
 	u8 session_id[128];
 	size_t id_len;
 	u8 *id_peer;
 	size_t id_peer_len;
 #define MAX_NUM_CSUITES 2
 	struct eap_gpsk_csuite csuite_list[MAX_NUM_CSUITES];
 	size_t csuite_count;
 	int vendor; /* CSuite/Vendor */
 	int specifier; /* CSuite/Specifier */
 };


 static const char * eap_gpsk_state_txt(int state)
 {
 	switch (state) {
 	case GPSK_1:
 		return "GPSK-1";
 	case GPSK_3:
 		return "GPSK-3";
 	case SUCCESS:
 		return "SUCCESS";
 	case FAILURE:
 		return "FAILURE";
 	default:
 		return "?";
 	}
 }


 static void eap_gpsk_state(struct eap_gpsk_data *data, int state)
 {
 	wpa_printf(MSG_DEBUG, "EAP-GPSK: %s -> %s",
 		   eap_gpsk_state_txt(data->state),
 		   eap_gpsk_state_txt(state));
 	data->state = state;
 }


 static void * eap_gpsk_init(struct eap_sm *sm)
 {
 	struct eap_gpsk_data *data;

 	data = os_zalloc(sizeof(*data));
 	if (data == NULL)
 		return NULL;
 	data->state = GPSK_1;

 	data->csuite_count = 0;
 	if (eap_gpsk_supported_ciphersuite(EAP_GPSK_VENDOR_IETF,
 					   EAP_GPSK_CIPHER_AES)) {
 		WPA_PUT_BE32(data->csuite_list[data->csuite_count].vendor,
 			     EAP_GPSK_VENDOR_IETF);
 		WPA_PUT_BE16(data->csuite_list[data->csuite_count].specifier,
 			     EAP_GPSK_CIPHER_AES);
 		data->csuite_count++;
 	}
 	if (eap_gpsk_supported_ciphersuite(EAP_GPSK_VENDOR_IETF,
 					   EAP_GPSK_CIPHER_SHA256)) {
 		WPA_PUT_BE32(data->csuite_list[data->csuite_count].vendor,
 			     EAP_GPSK_VENDOR_IETF);
 		WPA_PUT_BE16(data->csuite_list[data->csuite_count].specifier,
 			     EAP_GPSK_CIPHER_SHA256);
 		data->csuite_count++;
 	}

 	return data;
 }


 static void eap_gpsk_reset(struct eap_sm *sm, void *priv)
 {
 	struct eap_gpsk_data *data = priv;
 	os_free(data->id_peer);
 	bin_clear_free(data, sizeof(*data));
 }


 static struct wpabuf * eap_gpsk_build_gpsk_1(struct eap_sm *sm,
 					     struct eap_gpsk_data *data, u8 id)
 {
 	size_t len;
 	struct wpabuf *req;

 	wpa_printf(MSG_DEBUG, "EAP-GPSK: Request/GPSK-1");

 	if (random_get_bytes(data->rand_server, EAP_GPSK_RAND_LEN)) {
 		wpa_printf(MSG_ERROR, "EAP-GPSK: Failed to get random data");
 		eap_gpsk_state(data, FAILURE);
 		return NULL;
 	}
 	wpa_hexdump(MSG_MSGDUMP, "EAP-GPSK: RAND_Server",
 		    data->rand_server, EAP_GPSK_RAND_LEN);

 	len = 1 + 2 + sm->server_id_len + EAP_GPSK_RAND_LEN + 2 +
 		data->csuite_count * sizeof(struct eap_gpsk_csuite);
 	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_GPSK, len,
 			    EAP_CODE_REQUEST, id);
 	if (req == NULL) {
 		wpa_printf(MSG_ERROR, "EAP-GPSK: Failed to allocate memory "
 			   "for request/GPSK-1");
 		eap_gpsk_state(data, FAILURE);
 		return NULL;
 	}

 	wpabuf_put_u8(req, EAP_GPSK_OPCODE_GPSK_1);
 	wpabuf_put_be16(req, sm->server_id_len);
 	wpabuf_put_data(req, sm->server_id, sm->server_id_len);
 	wpabuf_put_data(req, data->rand_server, EAP_GPSK_RAND_LEN);
 	wpabuf_put_be16(req,
 			data->csuite_count * sizeof(struct eap_gpsk_csuite));
 	wpabuf_put_data(req, data->csuite_list,
 			data->csuite_count * sizeof(struct eap_gpsk_csuite));

 	return req;
 }


 static struct wpabuf * eap_gpsk_build_gpsk_3(struct eap_sm *sm,
 					     struct eap_gpsk_data *data, u8 id)
 {
 	u8 *pos, *start;
 	size_t len, miclen;
 	struct eap_gpsk_csuite *csuite;
 	struct wpabuf *req;

 	wpa_printf(MSG_DEBUG, "EAP-GPSK: Request/GPSK-3");

 	miclen = eap_gpsk_mic_len(data->vendor, data->specifier);
 	len = 1 + 2 * EAP_GPSK_RAND_LEN + 2 + sm->server_id_len +
 		sizeof(struct eap_gpsk_csuite) + 2 + miclen;
 	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_GPSK, len,
 			    EAP_CODE_REQUEST, id);
 	if (req == NULL) {
 		wpa_printf(MSG_ERROR, "EAP-GPSK: Failed to allocate memory "
 			   "for request/GPSK-3");
 		eap_gpsk_state(data, FAILURE);
 		return NULL;
 	}

 	wpabuf_put_u8(req, EAP_GPSK_OPCODE_GPSK_3);
 	start = wpabuf_put(req, 0);

 	wpabuf_put_data(req, data->rand_peer, EAP_GPSK_RAND_LEN);
 	wpabuf_put_data(req, data->rand_server, EAP_GPSK_RAND_LEN);
 	wpabuf_put_be16(req, sm->server_id_len);
 	wpabuf_put_data(req, sm->server_id, sm->server_id_len);
 	csuite = wpabuf_put(req, sizeof(*csuite));
 	WPA_PUT_BE32(csuite->vendor, data->vendor);
 	WPA_PUT_BE16(csuite->specifier, data->specifier);

 	/* no PD_Payload_2 */
 	wpabuf_put_be16(req, 0);

 	pos = wpabuf_put(req, miclen);
 	if (eap_gpsk_compute_mic(data->sk, data->sk_len, data->vendor,
 				 data->specifier, start, pos - start, pos) < 0)
 	{
 		os_free(req);
 		eap_gpsk_state(data, FAILURE);
 		return NULL;
 	}

 	return req;
 }


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

 	switch (data->state) {
 	case GPSK_1:
 		return eap_gpsk_build_gpsk_1(sm, data, id);
 	case GPSK_3:
 		return eap_gpsk_build_gpsk_3(sm, data, id);
 	default:
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Unknown state %d in buildReq",
 			   data->state);
 		break;
 	}
 	return NULL;
 }


 static Boolean eap_gpsk_check(struct eap_sm *sm, void *priv,
 			      struct wpabuf *respData)
 {
 	struct eap_gpsk_data *data = priv;
 	const u8 *pos;
 	size_t len;

 	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GPSK, respData, &len);
 	if (pos == NULL || len < 1) {
 		wpa_printf(MSG_INFO, "EAP-GPSK: Invalid frame");
 		return TRUE;
 	}

 	wpa_printf(MSG_DEBUG, "EAP-GPSK: Received frame: opcode=%d", *pos);

 	if (data->state == GPSK_1 && *pos == EAP_GPSK_OPCODE_GPSK_2)
 		return FALSE;

 	if (data->state == GPSK_3 && *pos == EAP_GPSK_OPCODE_GPSK_4)
 		return FALSE;

 	wpa_printf(MSG_INFO, "EAP-GPSK: Unexpected opcode=%d in state=%d",
 		   *pos, data->state);

 	return TRUE;
 }


 static void eap_gpsk_process_gpsk_2(struct eap_sm *sm,
 				    struct eap_gpsk_data *data,
 				    const u8 *payload, size_t payloadlen)
 {
 	const u8 *pos, *end;
 	u16 alen;
 	const struct eap_gpsk_csuite *csuite;
 	size_t i, miclen;
 	u8 mic[EAP_GPSK_MAX_MIC_LEN];

 	if (data->state != GPSK_1)
 		return;

 	wpa_printf(MSG_DEBUG, "EAP-GPSK: Received Response/GPSK-2");

 	pos = payload;
 	end = payload + payloadlen;

 	if (end - pos < 2) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "ID_Peer length");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	alen = WPA_GET_BE16(pos);
 	pos += 2;
 	if (end - pos < alen) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "ID_Peer");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	os_free(data->id_peer);
 	data->id_peer = os_malloc(alen);
 	if (data->id_peer == NULL) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Not enough memory to store "
 			   "%d-octet ID_Peer", alen);
 		return;
 	}
 	os_memcpy(data->id_peer, pos, alen);
 	data->id_peer_len = alen;
 	wpa_hexdump_ascii(MSG_DEBUG, "EAP-GPSK: ID_Peer",
 			  data->id_peer, data->id_peer_len);
 	pos += alen;

 	if (end - pos < 2) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "ID_Server length");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	alen = WPA_GET_BE16(pos);
 	pos += 2;
 	if (end - pos < alen) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "ID_Server");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	if (alen != sm->server_id_len ||
 	    os_memcmp(pos, sm->server_id, alen) != 0) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: ID_Server in GPSK-1 and "
 			   "GPSK-2 did not match");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	pos += alen;

 	if (end - pos < EAP_GPSK_RAND_LEN) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "RAND_Peer");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	os_memcpy(data->rand_peer, pos, EAP_GPSK_RAND_LEN);
 	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: RAND_Peer",
 		    data->rand_peer, EAP_GPSK_RAND_LEN);
 	pos += EAP_GPSK_RAND_LEN;

 	if (end - pos < EAP_GPSK_RAND_LEN) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "RAND_Server");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	if (os_memcmp(data->rand_server, pos, EAP_GPSK_RAND_LEN) != 0) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: RAND_Server in GPSK-1 and "
 			   "GPSK-2 did not match");
 		wpa_hexdump(MSG_DEBUG, "EAP-GPSK: RAND_Server in GPSK-1",
 			    data->rand_server, EAP_GPSK_RAND_LEN);
 		wpa_hexdump(MSG_DEBUG, "EAP-GPSK: RAND_Server in GPSK-2",
 			    pos, EAP_GPSK_RAND_LEN);
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	pos += EAP_GPSK_RAND_LEN;

 	if (end - pos < 2) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "CSuite_List length");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	alen = WPA_GET_BE16(pos);
 	pos += 2;
 	if (end - pos < alen) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "CSuite_List");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	if (alen != data->csuite_count * sizeof(struct eap_gpsk_csuite) ||
 	    os_memcmp(pos, data->csuite_list, alen) != 0) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: CSuite_List in GPSK-1 and "
 			   "GPSK-2 did not match");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	pos += alen;

 	if (end - pos < (int) sizeof(*csuite)) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "CSuite_Sel");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	csuite = (const struct eap_gpsk_csuite *) pos;
 	for (i = 0; i < data->csuite_count; i++) {
 		if (os_memcmp(csuite, &data->csuite_list[i], sizeof(*csuite))
 		    == 0)
 			break;
 	}
 	if (i == data->csuite_count) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Peer selected unsupported "
 			   "ciphersuite %d:%d",
 			   WPA_GET_BE32(csuite->vendor),
 			   WPA_GET_BE16(csuite->specifier));
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	data->vendor = WPA_GET_BE32(csuite->vendor);
 	data->specifier = WPA_GET_BE16(csuite->specifier);
 	wpa_printf(MSG_DEBUG, "EAP-GPSK: CSuite_Sel %d:%d",
 		   data->vendor, data->specifier);
 	pos += sizeof(*csuite);

 	if (end - pos < 2) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "PD_Payload_1 length");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	alen = WPA_GET_BE16(pos);
 	pos += 2;
 	if (end - pos < alen) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "PD_Payload_1");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: PD_Payload_1", pos, alen);
 	pos += alen;

 	if (sm->user == NULL || sm->user->password == NULL) {
 		wpa_printf(MSG_INFO, "EAP-GPSK: No PSK/password configured "
 			   "for the user");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}

 	if (eap_gpsk_derive_keys(sm->user->password, sm->user->password_len,
 				 data->vendor, data->specifier,
 				 data->rand_peer, data->rand_server,
 				 data->id_peer, data->id_peer_len,
 				 sm->server_id, sm->server_id_len,
 				 data->msk, data->emsk,
 				 data->sk, &data->sk_len,
 				 data->pk, &data->pk_len) < 0) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Failed to derive keys");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}

 	if (eap_gpsk_derive_session_id(sm->user->password,
 				       sm->user->password_len,
 				       data->vendor, data->specifier,
 				       data->rand_peer, data->rand_server,
 				       data->id_peer, data->id_peer_len,
 				       sm->server_id, sm->server_id_len,
 				       EAP_TYPE_GPSK,
 				       data->session_id, &data->id_len) < 0) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Failed to derive Session-Id");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Derived Session-Id",
 		    data->session_id, data->id_len);

 	miclen = eap_gpsk_mic_len(data->vendor, data->specifier);
 	if (end - pos < (int) miclen) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Message too short for MIC "
 			   "(left=%lu miclen=%lu)",
 			   (unsigned long) (end - pos),
 			   (unsigned long) miclen);
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	if (eap_gpsk_compute_mic(data->sk, data->sk_len, data->vendor,
 				 data->specifier, payload, pos - payload, mic)
 	    < 0) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Failed to compute MIC");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	if (os_memcmp_const(mic, pos, miclen) != 0) {
 		wpa_printf(MSG_INFO, "EAP-GPSK: Incorrect MIC in GPSK-2");
 		wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Received MIC", pos, miclen);
 		wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Computed MIC", mic, miclen);
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	pos += miclen;

 	if (pos != end) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Ignored %lu bytes of extra "
 			   "data in the end of GPSK-2",
 			   (unsigned long) (end - pos));
 	}

 	eap_gpsk_state(data, GPSK_3);
 }


 static void eap_gpsk_process_gpsk_4(struct eap_sm *sm,
 				    struct eap_gpsk_data *data,
 				    const u8 *payload, size_t payloadlen)
 {
 	const u8 *pos, *end;
 	u16 alen;
 	size_t miclen;
 	u8 mic[EAP_GPSK_MAX_MIC_LEN];

 	if (data->state != GPSK_3)
 		return;

 	wpa_printf(MSG_DEBUG, "EAP-GPSK: Received Response/GPSK-4");

 	pos = payload;
 	end = payload + payloadlen;

 	if (end - pos < 2) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "PD_Payload_1 length");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	alen = WPA_GET_BE16(pos);
 	pos += 2;
 	if (end - pos < alen) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
 			   "PD_Payload_1");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: PD_Payload_1", pos, alen);
 	pos += alen;

 	miclen = eap_gpsk_mic_len(data->vendor, data->specifier);
 	if (end - pos < (int) miclen) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Message too short for MIC "
 			   "(left=%lu miclen=%lu)",
 			   (unsigned long) (end - pos),
 			   (unsigned long) miclen);
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	if (eap_gpsk_compute_mic(data->sk, data->sk_len, data->vendor,
 				 data->specifier, payload, pos - payload, mic)
 	    < 0) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Failed to compute MIC");
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	if (os_memcmp_const(mic, pos, miclen) != 0) {
 		wpa_printf(MSG_INFO, "EAP-GPSK: Incorrect MIC in GPSK-4");
 		wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Received MIC", pos, miclen);
 		wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Computed MIC", mic, miclen);
 		eap_gpsk_state(data, FAILURE);
 		return;
 	}
 	pos += miclen;

 	if (pos != end) {
 		wpa_printf(MSG_DEBUG, "EAP-GPSK: Ignored %lu bytes of extra "
 			   "data in the end of GPSK-4",
 			   (unsigned long) (end - pos));
 	}

 	eap_gpsk_state(data, SUCCESS);
 }


 static void eap_gpsk_process(struct eap_sm *sm, void *priv,
 			     struct wpabuf *respData)
 {
 	struct eap_gpsk_data *data = priv;
 	const u8 *pos;
 	size_t len;

 	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GPSK, respData, &len);
 	if (pos == NULL || len < 1)
 		return;

 	switch (*pos) {
 	case EAP_GPSK_OPCODE_GPSK_2:
 		eap_gpsk_process_gpsk_2(sm, data, pos + 1, len - 1);
 		break;
 	case EAP_GPSK_OPCODE_GPSK_4:
 		eap_gpsk_process_gpsk_4(sm, data, pos + 1, len - 1);
 		break;
 	}
 }


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


 static u8 * eap_gpsk_getKey(struct eap_sm *sm, void *priv, size_t *len)
 {
 	struct eap_gpsk_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_gpsk_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
 {
 	struct eap_gpsk_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_gpsk_isSuccess(struct eap_sm *sm, void *priv)
 {
 	struct eap_gpsk_data *data = priv;
 	return data->state == SUCCESS;
 }


 static u8 * eap_gpsk_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
 {
 	struct eap_gpsk_data *data = priv;
 	u8 *sid;

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

 	sid = os_malloc(data->id_len);
 	if (sid == NULL)
 		return NULL;
 	os_memcpy(sid, data->session_id, data->id_len);
 	*len = data->id_len;

 	return sid;
 }


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

 	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
 				      EAP_VENDOR_IETF, EAP_TYPE_GPSK, "GPSK");
 	if (eap == NULL)
 		return -1;

 	eap->init = eap_gpsk_init;
 	eap->reset = eap_gpsk_reset;
 	eap->buildReq = eap_gpsk_buildReq;
 	eap->check = eap_gpsk_check;
 	eap->process = eap_gpsk_process;
 	eap->isDone = eap_gpsk_isDone;
 	eap->getKey = eap_gpsk_getKey;
 	eap->isSuccess = eap_gpsk_isSuccess;
 	eap->get_emsk = eap_gpsk_get_emsk;
 	eap->getSessionId = eap_gpsk_get_session_id;

 	ret = eap_server_method_register(eap);
 	if (ret)
 		eap_server_method_free(eap);
 	return ret;
 }
	/*
	* hostapd / EAP-GPSK (RFC 5433) 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_gpsk_common.h"


	struct eap_gpsk_data {
	enum { GPSK_1, GPSK_3, SUCCESS, FAILURE } state;
	u8 rand_server[EAP_GPSK_RAND_LEN];
	u8 rand_peer[EAP_GPSK_RAND_LEN];
	u8 msk[EAP_MSK_LEN];
	u8 emsk[EAP_EMSK_LEN];
	u8 sk[EAP_GPSK_MAX_SK_LEN];
	size_t sk_len;
	u8 pk[EAP_GPSK_MAX_PK_LEN];
	size_t pk_len;
	u8 session_id[128];
	size_t id_len;
	u8 *id_peer;
	size_t id_peer_len;
	#define MAX_NUM_CSUITES 2
	struct eap_gpsk_csuite csuite_list[MAX_NUM_CSUITES];
	size_t csuite_count;
	int vendor; /* CSuite/Vendor */
	int specifier; /* CSuite/Specifier */
	};


	static const char * eap_gpsk_state_txt(int state)
	{
	switch (state) {
	case GPSK_1:
	return "GPSK-1";
	case GPSK_3:
	return "GPSK-3";
	case SUCCESS:
	return "SUCCESS";
	case FAILURE:
	return "FAILURE";
	default:
	return "?";
	}
	}


	static void eap_gpsk_state(struct eap_gpsk_data *data, int state)
	{
	wpa_printf(MSG_DEBUG, "EAP-GPSK: %s -> %s",
	eap_gpsk_state_txt(data->state),
	eap_gpsk_state_txt(state));
	data->state = state;
	}


	static void * eap_gpsk_init(struct eap_sm *sm)
	{
	struct eap_gpsk_data *data;

	data = os_zalloc(sizeof(*data));
	if (data == NULL)
	return NULL;
	data->state = GPSK_1;

	data->csuite_count = 0;
	if (eap_gpsk_supported_ciphersuite(EAP_GPSK_VENDOR_IETF,
	EAP_GPSK_CIPHER_AES)) {
	WPA_PUT_BE32(data->csuite_list[data->csuite_count].vendor,
	EAP_GPSK_VENDOR_IETF);
	WPA_PUT_BE16(data->csuite_list[data->csuite_count].specifier,
	EAP_GPSK_CIPHER_AES);
	data->csuite_count++;
	}
	if (eap_gpsk_supported_ciphersuite(EAP_GPSK_VENDOR_IETF,
	EAP_GPSK_CIPHER_SHA256)) {
	WPA_PUT_BE32(data->csuite_list[data->csuite_count].vendor,
	EAP_GPSK_VENDOR_IETF);
	WPA_PUT_BE16(data->csuite_list[data->csuite_count].specifier,
	EAP_GPSK_CIPHER_SHA256);
	data->csuite_count++;
	}

	return data;
	}


	static void eap_gpsk_reset(struct eap_sm sm, void priv)
	{
	struct eap_gpsk_data *data = priv;
	os_free(data->id_peer);
	bin_clear_free(data, sizeof(*data));
	}


	static struct wpabuf * eap_gpsk_build_gpsk_1(struct eap_sm *sm,
	struct eap_gpsk_data *data, u8 id)
	{
	size_t len;
	struct wpabuf *req;

	wpa_printf(MSG_DEBUG, "EAP-GPSK: Request/GPSK-1");

	if (random_get_bytes(data->rand_server, EAP_GPSK_RAND_LEN)) {
	wpa_printf(MSG_ERROR, "EAP-GPSK: Failed to get random data");
	eap_gpsk_state(data, FAILURE);
	return NULL;
	}
	wpa_hexdump(MSG_MSGDUMP, "EAP-GPSK: RAND_Server",
	data->rand_server, EAP_GPSK_RAND_LEN);

	len = 1 + 2 + sm->server_id_len + EAP_GPSK_RAND_LEN + 2 +
	data->csuite_count * sizeof(struct eap_gpsk_csuite);
	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_GPSK, len,
	EAP_CODE_REQUEST, id);
	if (req == NULL) {
	wpa_printf(MSG_ERROR, "EAP-GPSK: Failed to allocate memory "
	"for request/GPSK-1");
	eap_gpsk_state(data, FAILURE);
	return NULL;
	}

	wpabuf_put_u8(req, EAP_GPSK_OPCODE_GPSK_1);
	wpabuf_put_be16(req, sm->server_id_len);
	wpabuf_put_data(req, sm->server_id, sm->server_id_len);
	wpabuf_put_data(req, data->rand_server, EAP_GPSK_RAND_LEN);
	wpabuf_put_be16(req,
	data->csuite_count * sizeof(struct eap_gpsk_csuite));
	wpabuf_put_data(req, data->csuite_list,
	data->csuite_count * sizeof(struct eap_gpsk_csuite));

	return req;
	}


	static struct wpabuf * eap_gpsk_build_gpsk_3(struct eap_sm *sm,
	struct eap_gpsk_data *data, u8 id)
	{
	u8 pos, start;
	size_t len, miclen;
	struct eap_gpsk_csuite *csuite;
	struct wpabuf *req;

	wpa_printf(MSG_DEBUG, "EAP-GPSK: Request/GPSK-3");

	miclen = eap_gpsk_mic_len(data->vendor, data->specifier);
	len = 1 + 2 * EAP_GPSK_RAND_LEN + 2 + sm->server_id_len +
	sizeof(struct eap_gpsk_csuite) + 2 + miclen;
	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_GPSK, len,
	EAP_CODE_REQUEST, id);
	if (req == NULL) {
	wpa_printf(MSG_ERROR, "EAP-GPSK: Failed to allocate memory "
	"for request/GPSK-3");
	eap_gpsk_state(data, FAILURE);
	return NULL;
	}

	wpabuf_put_u8(req, EAP_GPSK_OPCODE_GPSK_3);
	start = wpabuf_put(req, 0);

	wpabuf_put_data(req, data->rand_peer, EAP_GPSK_RAND_LEN);
	wpabuf_put_data(req, data->rand_server, EAP_GPSK_RAND_LEN);
	wpabuf_put_be16(req, sm->server_id_len);
	wpabuf_put_data(req, sm->server_id, sm->server_id_len);
	csuite = wpabuf_put(req, sizeof(*csuite));
	WPA_PUT_BE32(csuite->vendor, data->vendor);
	WPA_PUT_BE16(csuite->specifier, data->specifier);

	/* no PD_Payload_2 */
	wpabuf_put_be16(req, 0);

	pos = wpabuf_put(req, miclen);
	if (eap_gpsk_compute_mic(data->sk, data->sk_len, data->vendor,
	data->specifier, start, pos - start, pos) < 0)
	{
	os_free(req);
	eap_gpsk_state(data, FAILURE);
	return NULL;
	}

	return req;
	}


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

	switch (data->state) {
	case GPSK_1:
	return eap_gpsk_build_gpsk_1(sm, data, id);
	case GPSK_3:
	return eap_gpsk_build_gpsk_3(sm, data, id);
	default:
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Unknown state %d in buildReq",
	data->state);
	break;
	}
	return NULL;
	}


	static Boolean eap_gpsk_check(struct eap_sm sm, void priv,
	struct wpabuf *respData)
	{
	struct eap_gpsk_data *data = priv;
	const u8 *pos;
	size_t len;

	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GPSK, respData, &len);
	if (pos == NULL \|\| len < 1) {
	wpa_printf(MSG_INFO, "EAP-GPSK: Invalid frame");
	return TRUE;
	}

	wpa_printf(MSG_DEBUG, "EAP-GPSK: Received frame: opcode=%d", *pos);

	if (data->state == GPSK_1 && *pos == EAP_GPSK_OPCODE_GPSK_2)
	return FALSE;

	if (data->state == GPSK_3 && *pos == EAP_GPSK_OPCODE_GPSK_4)
	return FALSE;

	wpa_printf(MSG_INFO, "EAP-GPSK: Unexpected opcode=%d in state=%d",
	*pos, data->state);

	return TRUE;
	}


	static void eap_gpsk_process_gpsk_2(struct eap_sm *sm,
	struct eap_gpsk_data *data,
	const u8 *payload, size_t payloadlen)
	{
	const u8 pos, end;
	u16 alen;
	const struct eap_gpsk_csuite *csuite;
	size_t i, miclen;
	u8 mic[EAP_GPSK_MAX_MIC_LEN];

	if (data->state != GPSK_1)
	return;

	wpa_printf(MSG_DEBUG, "EAP-GPSK: Received Response/GPSK-2");

	pos = payload;
	end = payload + payloadlen;

	if (end - pos < 2) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"ID_Peer length");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	alen = WPA_GET_BE16(pos);
	pos += 2;
	if (end - pos < alen) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"ID_Peer");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	os_free(data->id_peer);
	data->id_peer = os_malloc(alen);
	if (data->id_peer == NULL) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Not enough memory to store "
	"%d-octet ID_Peer", alen);
	return;
	}
	os_memcpy(data->id_peer, pos, alen);
	data->id_peer_len = alen;
	wpa_hexdump_ascii(MSG_DEBUG, "EAP-GPSK: ID_Peer",
	data->id_peer, data->id_peer_len);
	pos += alen;

	if (end - pos < 2) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"ID_Server length");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	alen = WPA_GET_BE16(pos);
	pos += 2;
	if (end - pos < alen) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"ID_Server");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	if (alen != sm->server_id_len \|\|
	os_memcmp(pos, sm->server_id, alen) != 0) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: ID_Server in GPSK-1 and "
	"GPSK-2 did not match");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	pos += alen;

	if (end - pos < EAP_GPSK_RAND_LEN) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"RAND_Peer");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	os_memcpy(data->rand_peer, pos, EAP_GPSK_RAND_LEN);
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: RAND_Peer",
	data->rand_peer, EAP_GPSK_RAND_LEN);
	pos += EAP_GPSK_RAND_LEN;

	if (end - pos < EAP_GPSK_RAND_LEN) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"RAND_Server");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	if (os_memcmp(data->rand_server, pos, EAP_GPSK_RAND_LEN) != 0) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: RAND_Server in GPSK-1 and "
	"GPSK-2 did not match");
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: RAND_Server in GPSK-1",
	data->rand_server, EAP_GPSK_RAND_LEN);
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: RAND_Server in GPSK-2",
	pos, EAP_GPSK_RAND_LEN);
	eap_gpsk_state(data, FAILURE);
	return;
	}
	pos += EAP_GPSK_RAND_LEN;

	if (end - pos < 2) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"CSuite_List length");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	alen = WPA_GET_BE16(pos);
	pos += 2;
	if (end - pos < alen) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"CSuite_List");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	if (alen != data->csuite_count * sizeof(struct eap_gpsk_csuite) \|\|
	os_memcmp(pos, data->csuite_list, alen) != 0) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: CSuite_List in GPSK-1 and "
	"GPSK-2 did not match");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	pos += alen;

	if (end - pos < (int) sizeof(*csuite)) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"CSuite_Sel");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	csuite = (const struct eap_gpsk_csuite *) pos;
	for (i = 0; i < data->csuite_count; i++) {
	if (os_memcmp(csuite, &data->csuite_list[i], sizeof(*csuite))
	== 0)
	break;
	}
	if (i == data->csuite_count) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Peer selected unsupported "
	"ciphersuite %d:%d",
	WPA_GET_BE32(csuite->vendor),
	WPA_GET_BE16(csuite->specifier));
	eap_gpsk_state(data, FAILURE);
	return;
	}
	data->vendor = WPA_GET_BE32(csuite->vendor);
	data->specifier = WPA_GET_BE16(csuite->specifier);
	wpa_printf(MSG_DEBUG, "EAP-GPSK: CSuite_Sel %d:%d",
	data->vendor, data->specifier);
	pos += sizeof(*csuite);

	if (end - pos < 2) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"PD_Payload_1 length");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	alen = WPA_GET_BE16(pos);
	pos += 2;
	if (end - pos < alen) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"PD_Payload_1");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: PD_Payload_1", pos, alen);
	pos += alen;

	if (sm->user == NULL \|\| sm->user->password == NULL) {
	wpa_printf(MSG_INFO, "EAP-GPSK: No PSK/password configured "
	"for the user");
	eap_gpsk_state(data, FAILURE);
	return;
	}

	if (eap_gpsk_derive_keys(sm->user->password, sm->user->password_len,
	data->vendor, data->specifier,
	data->rand_peer, data->rand_server,
	data->id_peer, data->id_peer_len,
	sm->server_id, sm->server_id_len,
	data->msk, data->emsk,
	data->sk, &data->sk_len,
	data->pk, &data->pk_len) < 0) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Failed to derive keys");
	eap_gpsk_state(data, FAILURE);
	return;
	}

	if (eap_gpsk_derive_session_id(sm->user->password,
	sm->user->password_len,
	data->vendor, data->specifier,
	data->rand_peer, data->rand_server,
	data->id_peer, data->id_peer_len,
	sm->server_id, sm->server_id_len,
	EAP_TYPE_GPSK,
	data->session_id, &data->id_len) < 0) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Failed to derive Session-Id");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Derived Session-Id",
	data->session_id, data->id_len);

	miclen = eap_gpsk_mic_len(data->vendor, data->specifier);
	if (end - pos < (int) miclen) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Message too short for MIC "
	"(left=%lu miclen=%lu)",
	(unsigned long) (end - pos),
	(unsigned long) miclen);
	eap_gpsk_state(data, FAILURE);
	return;
	}
	if (eap_gpsk_compute_mic(data->sk, data->sk_len, data->vendor,
	data->specifier, payload, pos - payload, mic)
	< 0) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Failed to compute MIC");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	if (os_memcmp_const(mic, pos, miclen) != 0) {
	wpa_printf(MSG_INFO, "EAP-GPSK: Incorrect MIC in GPSK-2");
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Received MIC", pos, miclen);
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Computed MIC", mic, miclen);
	eap_gpsk_state(data, FAILURE);
	return;
	}
	pos += miclen;

	if (pos != end) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Ignored %lu bytes of extra "
	"data in the end of GPSK-2",
	(unsigned long) (end - pos));
	}

	eap_gpsk_state(data, GPSK_3);
	}


	static void eap_gpsk_process_gpsk_4(struct eap_sm *sm,
	struct eap_gpsk_data *data,
	const u8 *payload, size_t payloadlen)
	{
	const u8 pos, end;
	u16 alen;
	size_t miclen;
	u8 mic[EAP_GPSK_MAX_MIC_LEN];

	if (data->state != GPSK_3)
	return;

	wpa_printf(MSG_DEBUG, "EAP-GPSK: Received Response/GPSK-4");

	pos = payload;
	end = payload + payloadlen;

	if (end - pos < 2) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"PD_Payload_1 length");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	alen = WPA_GET_BE16(pos);
	pos += 2;
	if (end - pos < alen) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Too short message for "
	"PD_Payload_1");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: PD_Payload_1", pos, alen);
	pos += alen;

	miclen = eap_gpsk_mic_len(data->vendor, data->specifier);
	if (end - pos < (int) miclen) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Message too short for MIC "
	"(left=%lu miclen=%lu)",
	(unsigned long) (end - pos),
	(unsigned long) miclen);
	eap_gpsk_state(data, FAILURE);
	return;
	}
	if (eap_gpsk_compute_mic(data->sk, data->sk_len, data->vendor,
	data->specifier, payload, pos - payload, mic)
	< 0) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Failed to compute MIC");
	eap_gpsk_state(data, FAILURE);
	return;
	}
	if (os_memcmp_const(mic, pos, miclen) != 0) {
	wpa_printf(MSG_INFO, "EAP-GPSK: Incorrect MIC in GPSK-4");
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Received MIC", pos, miclen);
	wpa_hexdump(MSG_DEBUG, "EAP-GPSK: Computed MIC", mic, miclen);
	eap_gpsk_state(data, FAILURE);
	return;
	}
	pos += miclen;

	if (pos != end) {
	wpa_printf(MSG_DEBUG, "EAP-GPSK: Ignored %lu bytes of extra "
	"data in the end of GPSK-4",
	(unsigned long) (end - pos));
	}

	eap_gpsk_state(data, SUCCESS);
	}


	static void eap_gpsk_process(struct eap_sm sm, void priv,
	struct wpabuf *respData)
	{
	struct eap_gpsk_data *data = priv;
	const u8 *pos;
	size_t len;

	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GPSK, respData, &len);
	if (pos == NULL \|\| len < 1)
	return;

	switch (*pos) {
	case EAP_GPSK_OPCODE_GPSK_2:
	eap_gpsk_process_gpsk_2(sm, data, pos + 1, len - 1);
	break;
	case EAP_GPSK_OPCODE_GPSK_4:
	eap_gpsk_process_gpsk_4(sm, data, pos + 1, len - 1);
	break;
	}
	}


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


	static u8 * eap_gpsk_getKey(struct eap_sm sm, void priv, size_t *len)
	{
	struct eap_gpsk_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_gpsk_get_emsk(struct eap_sm sm, void priv, size_t *len)
	{
	struct eap_gpsk_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_gpsk_isSuccess(struct eap_sm sm, void priv)
	{
	struct eap_gpsk_data *data = priv;
	return data->state == SUCCESS;
	}


	static u8 * eap_gpsk_get_session_id(struct eap_sm sm, void priv, size_t *len)
	{
	struct eap_gpsk_data *data = priv;
	u8 *sid;

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

	sid = os_malloc(data->id_len);
	if (sid == NULL)
	return NULL;
	os_memcpy(sid, data->session_id, data->id_len);
	*len = data->id_len;

	return sid;
	}


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

	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
	EAP_VENDOR_IETF, EAP_TYPE_GPSK, "GPSK");
	if (eap == NULL)
	return -1;

	eap->init = eap_gpsk_init;
	eap->reset = eap_gpsk_reset;
	eap->buildReq = eap_gpsk_buildReq;
	eap->check = eap_gpsk_check;
	eap->process = eap_gpsk_process;
	eap->isDone = eap_gpsk_isDone;
	eap->getKey = eap_gpsk_getKey;
	eap->isSuccess = eap_gpsk_isSuccess;
	eap->get_emsk = eap_gpsk_get_emsk;
	eap->getSessionId = eap_gpsk_get_session_id;

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